bluuebunny/crossref_metadata_2025 huggingface dataset:
Pretreatment with melatonin reduces volume of cerebral infarction in a rat middle cerebral artery occlusion stroke model
Authors: Pei Zhong , Pang S.F. , Cheung R.T.F.
Published: May 2003

Melatonin is a potent scavenger of free radicals and an indirect antioxidant. Recent studies have shown that melatonin possesses beneficial effects in experimental models of brain trauma and global cerebral ischemia. The effects of pretreatment with melatonin on volume of cerebral infarction were investigated in the present study. Adult male Sprague–Dawley rats were anesthetized with sodium pentobarbital to undergo right‐sided endovascular middle cerebral artery occlusion (MCAO) for 3 hr. A single dose of melatonin (1.5, 5, 15, or 50 mg/kg in 1 mL normal saline) or its vehicle was given via an intraperitoneal injection at 0.5 hr before MCAO. Relative infarction volumes on day 3 after MCAO were significantly reduced in the groups treated with melatonin at 5 (mean ± S.E.M., 15.7 ± 2.5%) or 15 (21.4 ± 3.1%) mg/kg but not at 1.5 (30.6 ± 3.5%) or 50 (26.7 ± 2.8%) mg/kg when compared with the vehicle group (33.9 ± 3.5%). There was no significant difference in the arterial blood pressure (BP), heart rate (HR) and relative cerebral blood flow among the experimental groups. These results indicate that pretreatment with melatonin at a dose between 5 and 15 mg/kg protects against focal cerebral ischemia.
Melatonin reduces memory changes and neural oxidative damage in mice treated with D‐galactose
Authors: Shen Yu‐Xian , Xu Shu‐Yun , Wei Wei , Sun Xiu‐Xia , Yang Jun , Liu Li‐Hua , Dong Chen
Published: May 2003

To investigate the role of melatonin in D‐galactose‐induced amnesic mice, the avoidance/escape and water maze tests were performed to evaluate their learning and memory function. Spectrophotometry was employed to determine the content of thiobarbituric acid‐reactive substances (TBARS) and the activities of antioxidative enzymes in the brain. The present results demonstrate that D‐galactose‐induced amnesic mice had significantly decreased learning and memory function. The reduced activities of superoxide dismutase and glutathione peroxidase and increased levels of TBARS were found in brain tissue of the amnesic mice. Melatonin, administered (ig) at doses of 0.1, 1, or 10 mg/kg to the D‐galactose‐treated mice for 3 months, was sufficient to block these changes. These data suggest that D‐galactose is involved in accelerating the brain aging process by elevating free radical generation and reducing antioxidative enzyme activities in vivo. Furthermore, the antioxidative activity of melatonin on the D‐galactose‐treated mice may account for, at least partially, the improvement of learning and memory function in the aging and amnesic model.
Long‐term melatonin administration increases polyunsaturated fatty acid percentage in plasma lipids of hypercholesterolemic rats
Authors: Pita María L. , Hoyos Marta , Martin‐Lacave Inés , Osuna Carmen , Fernández‐Santos Jose M. , Guerrero Juan M.
Published: May 2003

This study was designed to investigate the effect of melatonin on the fatty acid composition of plasma and tissue lipids. Melatonin administration to rats fed with a standard diet only increased long‐chain n‐6 polyunsaturated fatty acids (PUFA) in total plasma lipids and liver phospholipids but induced significant changes in hypercholesterolemic rats. In plasma, palmitoleic and oleic acids increased and n‐6 and n‐3 PUFA decreased in hypercholesterolemic rats; theses changes were reversed by melatonin administration. The analysis of lipid fractions revealed that only the cholesteryl ester fraction was affected by melatonin. Histological studies of the carotid artery intima revealed the appearance, in hypercholesterolemic rats, of fatty streaks produced by a mass of foam cells covered by the endothelium and by a thin layer of mononucleated cells. These changes were prevented by melatonin. We conclude that long‐term melatonin administration modifies the fatty acid composition of rat plasma and liver lipids and ameliorates the arterial fatty infiltration induced by cholesterol.
Protective effect of melatonin against cytotoxic actions of malondialdehyde: an in vitro study on human erythrocytes
Authors: Allegra M. , Gentile C. , Tesoriere L. , Livrea M. A.
Published: May 2003

Malondialdehyde (MDA), a by‐product of the oxidation of polyunsaturated fatty acids, is strongly cytotoxic. Here we report the in vitro ability of melatonin to protect intact human erythrocytes against the damage induced by the exposure to MDA. MDA at 20 μM caused marked variations in the red blood cell (RBC) membrane. High molecular weight fluorescent adducts were formed within minutes with membrane proteins. A 6‐hr incubation led to the oxidation of membrane lipids, as reflected by the formation of conjugated diene (CD) lipid hydroperoxides and oxidation of vitamin E, and to an increase of the high molecular weight fluorescent adducts, which were an indication of MDA finally generated in the cells. Functional damage to the membrane was evident as a leakage of K+ ions into the incubation medium, and an increased resistance to osmotic lysis. A time‐dependent hemolysis was observed by exposure of RBCs to 20 μM MDA for 6–12 hr. Melatonin was not a substrate for MDA, therefore it was not able to prevent the early formation of the adducts from the reaction of the MDA in the medium with membrane proteins. Melatonin, however, concentration‐dependent prevented the formation of CD lipid hydroperoxides. As a consequence of counteracting the membrane lipid oxidation, the indoleamine prevented the loss of vitamin E and the increase of the fluorescent proteinaceous adducts observed after a 6‐hr exposure to MDA. Melatonin also inhibited the K+ loss and returned to normal the osmotic resistance of the erythrocyte in the osmotic fragility test. By protecting membrane lipids and proteins, melatonin effectively prevented the MDA‐induced time‐dependent hemolysis. In the light of the known radical scavenging properties of melatonin, mechanisms of the cytoprotective effects of melatonin in our system are discussed.
Effects of physiological and pharmacological concentrations of melatonin on ischemia–reperfusion arrhythmias in rats: can the incidence of sudden cardiac death be reduced?
Authors: Sahna Engin , Olmez Ercument , Acet Ahmet
Published: May 2003

Cardiac arrhythmias during ischemia–reperfusion (I/R) are believed to be related to free radicals generated in the heart especially during the period of reperfusion. The pineal secretory product, melatonin, is known to be a potent free radical scavenger and its pharmacological concentrations have been shown to reduce the I/R‐induced arrhythmias in isolated rat hearts. However, the physiological role of melatonin in the prevention of these arrhythmias is unknown. Rats were pinealectomized (Px) or sham‐operated (non‐Px) (control) 2 months before the I/R studies. To produce arrhythmias, left main coronary artery was occluded for 7 min, followed by 7 min reperfusion, in anesthetized rats. The incidence of mortality resulted from irreversible ventricular fibrillation (VF) was found significantly higher in the Px rats (63%) than in the control group (25%). Melatonin administration (0.4 mg/kg, either before ischemia or reperfusion) to Px rats significantly reduced the incidence of total (irreversible plus reversible) and irreversible VF and returned them to control values. On the other hand, melatonin administration (0.4 and 4 mg/kg) to non‐Px rats failed to attenuate the I/R arrhythmias, significantly. These results suggest that physiological melatonin concentrations are important to reduce the I/R‐induced VF and mortality, while pharmacological concentrations of melatonin did not increase its beneficial effect on these arrhythmias. As melatonin levels have been reported to decrease with age, melatonin replacement therapy may attenuate the incidence of sudden cardiac death especially in older patients.
Receptor‐mediated modulation of avian caecal muscle contraction by melatonin: role of tyrosine protein kinase
Authors: Poon A.M.S. , Kravtsov G.M. , Pang S.F.
Published: May 2003

Melatonin receptors in the quail caecum were studied by 2[125I]iodomelatonin binding assay and the involvement of tyrosine protein kinase in the melatonin‐induced contraction was explored. The binding of 2[125I]iodomelatonin in the quail caecum membrane preparations was saturable, reversible and of high affinity with an equilibrium dissociation constant (Kd) of 24.6 ± 1.1 pm (n=7) and a maximum number of binding sites (Bmax) of 1.95 ± 0.09 fmol (mg/protein) (n=7). The relative order of potency of indoles in competing for 2[125I]iodomelatonin binding was: 2‐iodomelatonin > melatonin > 2‐phenylmelatonin >  6‐chloromelatonin > 6‐hydroxymelatonin > N‐acetylserotonin, indicating that ML1 receptors are involved. The binding was inhibited by Mel1b melatonin receptor antagonists, luzindole and 4‐phenyl‐2‐propionamidotetralin (4‐P‐PDOT) as well as by non‐hydrolyzable analogs of GTP like GTPγS and Gpp(NH)p but not by adenosine nucleotides. The latter suggests that the action of melatonin on the caecum is G‐protein linked. Cumulative addition of melatonin (1–300 nM) potentiated both the amplitude and frequency of spontaneous contractions in the quail caecum. The potentiation of rhythmic contractions was blocked by both luzindole and 4‐P‐PDOT. Antagonists of tyrosine kinase, genistein(2 μM) and erbstatin(4 μM) suppressed the modulation of spontaneous contractions by melatonin, but not inhibitors of protein kinase C (PKC) or protein kinase A (PKA). Melatonin‐induced increment in spontaneous contraction was blocked by nifedipine (0.4 nM). Thus, we suggest that melatonin potentiates spontaneous contraction in the quail caecum via interacting with G‐protein‐coupled Mel1b receptor which may activate L‐type Ca2+ channels by mobilizing tyrosine kinases.
Cyclophosphamide in treatment of systemic lupus erythematosus: 7 years’ experience
Authors: Feng P. H. , Jayaratnam F. J. , Tock E. P. C. , Seah C. S.
Published: May 2003

This paper describes our experience with cyclophosphamide in the treatment of systemic lupus erythematosus. Since 1965, 42 such patients have been treated either singly with cyclophosphamide or in combination with steroid. Serious complications have been rare except for amenorrhoea, which occurred in 14 out of 32 patients within the reproductive period. Our experience suggests that cyclophosphamide has an important, though not primary, part to play in the therapy of this disease.
Clinical and immunological profile of primary Sjogren's syndrome in Kuwait: First report from Middle East
Authors: Uppal Sukhbir Singh , Mutairi Moudhi Al , Malaviya Anand N
Published: May 2003

Aim: To describe the clinical and serological findings in primary Sjogren's syndrome (SS) patients seen in a teaching hospital in Kuwait.

Methods: Using the European and San Diego criteria for the diagnosis of SS, we studied 10 consecutive (nine female and one male) SS patients seen in our rheumatology clinic. All these patients fulfilled four or more of the diagnostic criteria for SS proposed by the European Community Study Group in 1993 as well as the more stringent San Diego criteria.

Results: The mean age of the patients at presentation was 32.9 years (SE 4.4 years), ranging from 15 to 56 years. The mean disease duration was 3.5 years (SE 1.4 years). The most frequently observed clinical manifestations were: xerostomia (80%); xerophthalmia (70%); and parotidomegaly (30%). The main extraglandular manifestation was arthritis (50%). The Schirmer test was positive in 90% and the rose Bengal test in 90%. The immunologic study showed antinuclear antibodies in 80% of patients, rheumatoid factor in 90%, anti‐Ro/SS‐A in 90% and anti‐La/SS‐B in 90%. Lip biopsy could be done in only six patients and showed characteristic focal lymphocytic infiltration of minor salivary glands in 67%. There was no statistically significant difference in the occurrence of parotidomegaly or arthritis in patients with disease onset before or after the age of 40 years. Likewise, there was no difference in the positivity of ANA, RF, ant‐Ro/SS‐A or anti‐La/SS‐B in the two age groups.

Conclusions: Although primary SS is typically said to be a disease of middle‐aged women, this does not seem to be the case in Kuwait, where 60% had disease onset below the age of 40 years. We could not find any notable differences in clinical and immunological characteristics between patients with primary SS from Kuwait and those reported from elsewhere, except for higher rates of serological abnormalities (RF, anti‐Ro/SS‐A, anti‐La‐SS‐B), probably due to genetic differences and the use of the strict San Diego criteria.
Use of complementary medicine in systemic lupus erythematosus patients in Malaysia
Authors: Goh E. , Tan L. C. , Chow S. K. , Teh L. K. , Yeap S. S.
Published: May 2003

Aim: To determine the prevalence of the use of complementary medicine in patients with systemic lupus erythematosus (SLE).

Method: A prospective survey was conducted of 132 patients using a standard questionnaire.

Results: Of the 132 patients, 15.2% were on alternative therapy and 56.7% were taking food supplements. The common types of alternative therapy taken were oral traditional herbs (50%) and noni juice (20%). Vitamin C, calcium, vitamin E, vitamin B, Spirulina, evening primrose oil, fish oil and multivitamins were the commonest food supplements. There was no significant relationships between taking alternative treatment and educational level (P = 0.16), income (P = 0.05) or race (P = 0.42) of the patients. The majority of these patients took these therapies or supplements for up to 1 year. Up to 70% of the patients had not consulted a doctor before taking these therapies, with immediate family members and friends being the main sources of recommendation. The majority of patients spent RM50−RM500 (US$13−US$132) for 2 months’ supply of medications. In conclusion, 15.2% of SLE patients in our study were on alternative therapy and 57.6% on food supplements.

Conclusion: Physicians should be aware of these practices which should be taken into account during the history‐taking and subsequent management of the patients.
Methotrexate versus chloroquine in the treatment of rheumatoid arthritis
Authors: Alam M. Rajibul , Haq Syed Atiqul , Majumder M. Mahabubul Islam , Das Shankar Narayan , Alam M. N.
Published: May 2003

Aims: The cost of treatment and monitoring of rheumatoid arthritis patients with more effective disease‐modifying drugs like methotrexate and sulphasalazine is prohibitive. This open random clinical trial was carried out with a view to assessing the status of chloroquine, the cheapest disease‐modifying drug, in the treatment of rheumatoid arthritis.

Method: A total of 47 cases were included in the study. Thirty subjects were randomly assigned to methotrexate and 14 to chloroquine groups. During 6 months follow‐up, five cases (three in chloroquine and two in methotrexate) dropped out because of side‐effects and inefficacy. Out of the remaining 42, 35 were female and five were male, with a mean age of 46.05 ± 14.12 years. Mean duration of the disease at the time of presentation was 5.53 ± 6.33 years. The two groups did not differ significantly in baseline demographics and disease activity variables.

Results: In both groups, most indices showed significant decrease in the disease activity. The difference in decreases in swollen joint count, tender joint count, joint swelling index and duration of morning stiffness were higher in the methotrexate compared to the chloroquine group. Inter‐group differences in the magnitudes of decreases were insignificant in other variables. At the end of 6 months, the response rate, according to the WHO/ILAR criteria, were 75% and 64% in methotrexate and chloroquine groups, respectively. The difference was not significant. Anorexia and nausea were the most common side‐effects in both groups and subsided with the passage of time despite continuation of therapy.

Conclusion: Considering low cost and a lesser need for close monitoring, chloroquine may be considered a choice in rheumatoid arthritis patients with mild disease and who are from underprivileged communities.
Quinacrine and hydroxychloroquine, a forgotten combination for patients with active systemic lupus erythematosus in Australasia?
Authors: Ching Daniel W. T.
Published: May 2003

In 1994, A 39‐year‐old Female Patient With Systemic Lupus Erythematosus (Sle) Was Diagnosed As Having Lupus‐induced Serositis. She Was Commenced On Hydroxychloroquine (Hcq) And Prednisone. Her Disease Kept Relapsing Whenever She Was Tailed Off Prednisone. In 1997, Quinacrine (Qn) Was Commenced, And Prednisone Was Gradually Stopped. Her Disease Has Remained In Remission On The Combination Of Hcq And Qn. In December 2000 She Ran Out Of Qn For A Week, And Within This Period She Started To Experience Fatigue And Polyarthralgia Again. Quinacrine Is Available From Compounding Pharmacies, And Is Relatively Cheap. The Combination Of Hcq And Qn In The Treatment Of Sle Should Be Considered More Often.
Possible coexistence of SLE and sarcoidosis in a Chinese female patient
Authors: Lee K. K. , Wong W. S.
Published: May 2003

Systemic lupus erythematosus (SLE) and sarcoidosis, both being multisystem disorders, share some common clinical features. However, while SLE is not an uncommon disease in the Chinese population, sarcoidosis is distinctly rare in the Chinese. We report a Chinese female patient whose presenting features tend to suggest a lupus‐like illness. However, eventually, the diagnosis of sarcoidosis was documented, based on the histological findings of her lymph node biopsy. The possible coexistence of SLE and sarcoidosis is discussed.
Juvenile dermatomyositis: Advances in understanding and management
Authors: Murray Kevin J.
Published: May 2003

The last few decades have produced major advances in the understanding of clinical aspects of inflammatory myositis disorders, both in children and adults. Though relatively rare in childhood, these conditions are often quite severe and require intensive treatments for considerable periods of time. Significant morbidity and occasional mortality still occur despite improvements in outcome. This improved outcome has resulted in part from the novel or better applications of medications already in use, as well as the availability of newer drugs. Few of these have been designed specifically for use in inflammatory myositis but have been drawn from therapeutic trials in other rheumatic disorders and areas of medicine such as oncology and transplantation medicine. Just as important have been the international efforts to design and validate specific outcome measures for all aspects of these disorders, both in childhood and adults, particularly to support the conduct of therapeutic trials. It is highly likely that as improvements in understanding of pathogenesis occur, more specific treatments with drugs such as biological agents will replace the more traditional therapeutic approaches and perhaps designed specifically on a patient‐by‐patient basis. This review highlights the important advances of the last decade and describes a management approach shared by many of the workers in this field. It focuses primarily on juvenile onset dermatomyositis (JDM) as this is the most common disorder seen, and experience with JDM forms the basis of management of the other disorders.
Pulsed Signal Therapy®: An overview
Authors: Markoll Richard , Da Silva Ferreira Dulce M. , Toohil Theresa K.
Published: May 2003

Pulsed Signal Therapy® (PST®) is a unique form of therapy that entails directing a specific physiological signal carried on a series of magnetic field pulses to the treatment site. These uniquely specific energy parameters are transmitted through the injured tissue to target the affected area via direct induction. The corrective PST® signal, carried on the magnetic wave‐pulse, induces a tiny electrical signal that mimics the physiological signaling normally occurring in healthy living organisms. In this way, it exerts its therapeutic effects by stimulating cellular repair. Double‐blind clinical trials and other open label randomized studies conducted in over 100,000 patients have consistently confirmed the long term efficacy and safety of PST® in patients suffering from osteoarthritis of the knee, cervical and lumbar spine. Data was collected over a 10 year period in the USA, Canada, France, Italy and Germany, by qualified specialists at major medical centers, or their affiliated teaching hospitals and other facilities.* Extensive studies in patients with temporomandibular joint disorder (TMJ) and tinnitus, not responsive to other therapies, have shown significant improvement, following PST®. Ergo PST has been successfully used in the treatment of chronic pain associated with connective tissue (cartilage, tendon, ligaments and bone) injury, osteoarthritis (OA or arthrosis) and also in the treatment of joint‐associated soft tissue injury (traumatic, including soft tissue injury). In effect, PST® has been shown to exert positive effects on both cartilage and dense connective tissue, and in stimulating the repair of bone‐tissue.
Factors associated with volatile solvent use among junior high school students in Kanto, Japan
Authors: Kikuchi Akiko , Wada Kiyoshi
Published: May 2003

Aims  To estimate the relative association between life‐time volatile solvent use and risk factors for usage.

Design  Cross‐sectional anonymous questionnaire survey.

Setting  Junior high schools in Kanto, Japan.

Participants  Junior high school students (n = 7744).

Measurements  Data on life‐time and past‐year solvent use, demographic variables, urbanization, regularity of waking patterns, school life, family life, peer relationships, prior alcohol and cigarette use and knowledge on harmful effects of solvent use.

Findings  Uni‐ and multivariate logistic regression analyses were conducted to estimate crude and adjusted odds ratios for each index. The primary findings were (1) ‘smoking cigarettes nearly every day’ (adjusted OR = 9.88, 95% Cl = 3.74, 26.12) and peer pressure measured by ‘been tempted to use solvents’ (adjusted OR = 9.53, 95% Cl = 4.84, 18.74) demonstrated the highest adjusted odds ratios; (2) being male (adjusted OR = 2.56, 95% Cl = 1.37, 4.76), seeing school life as ‘not at all enjoyable’ (adjusted OR = 2.69, 95% Cl = 1.03, 7.01) and family environment as ‘neither good nor bad’ (adjusted OR = 2.15, 95% Cl = 1.19, 3.88) also showed significant association; (3) life‐time alcohol use did not show a significant association in the multivariate model (adjusted OR = 0.80, 95% Cl = 0.30, 2.12); and (4) solvent use appeared independent of knowledge regarding its effects (‘death by acute intoxication’, ‘psychotic symptoms’, ‘amotivational syndrome’, ‘flashbacks’ adjusted ORs all non‐significant).

Conclusion  Alcohol use may not function as a gateway to solvent use in Japan. The reasons may be culture‐bound. A longitudinal study is required to test this hypothesis.
Marginality among older injectors in today's illicit drug culture: assessing the impact of ageing
Authors: Anderson Tammy L. , Levy Judith A.
Published: May 2003

Aims As conceptualized by Robert Park in 1928, the ‘marginal man’ occupies simultaneously an intermediate point between two distinct cultures that embody some level of contradictory normative expectations, behaviors and beliefs. This paper explores the influence of ageing and social change on the creation of marginality among injection drug users over age 50 who have been chronic heroin users since their youth.

Design Our data are drawn from in‐depth interviews with 40 (28 male and 12 female) not‐in‐drug‐treatment, active injecting drug users between the ages of 18 and 68.

Setting Our sample was recruited using street outreach as part of a larger, community‐based study conducted from a converted storefront in a high crime, economically depressed neighborhood on the west side of Chicago.

Findings As they aged, and under the pressures of social change, the older users whom we studied moved from center positioning in the illicit drug culture of their youth to the margins of a differing drug culture of today where they participate largely unseen by others. Nostalgic for the ‘Old School’ mores of the past, and unable to transcend or assimilate fully into the cultural practices and norms of the ‘New’, they respond to their predicament by embracing ‘poise’ in the face of loneliness, stress and fear of victimization.

Conclusions Our respondents’ experiences draw attention to the need to refine the field's theoretical and practical understandings of what it means to be marginal and its consequences for older drug users and people in general. The results also point to what happens when society changes but some of its members do not.
The effectiveness of personalized smoking cessation strategies for callers to a Quitline service
Authors: Borland Ron , Balmford James , Segan Catherine , Livingston Patricia , Owen Neville
Published: May 2003

Aim  To assess the effectiveness of a program of computer‐generated tailored advice for callers to a telephone helpline, and to assess whether it enhanced a series of callback telephone counselling sessions in aiding smoking cessation.

Design  Randomized controlled trial comparing: (1) untailored self‐help materials; (2) computer‐generated tailored advice only, and (3) computer‐generated tailored advice plus callback telephone counselling. Assessment surveys were conducted at baseline, 3, 6 and 12 months.

Setting  Victoria, Australia.

Participants  A total of 1578 smokers who called the Quitline service and agreed to participate.

Measurements  Smoking status at follow‐up; duration of cessation, if quit; use of nicotine replacement therapy; and extent of participation in the callback service.

Findings  At the 3‐month follow‐up, significantly more (χ2(2) = 16.9; P < 0.001) participants in the computer‐generated tailored advice plus telephone counselling condition were not smoking (21%) than in either the computer‐generated advice only (12%) or the control condition (12%). Proportions reporting not smoking at the 12‐month follow‐up were 26%, 23% and 22%, respectively (NS) for point prevalence, and for 9 months sustained abstinence; 8.2, 6.0, and 5.0 (NS). In the telephone counselling group, those receiving callbacks were more likely than those who did not to have sustained abstinence at 12 months (10.2 compared with 4.0, P < 0.05). Logistic regression on 3‐month data showed significant independent effects on cessation of telephone counselling and use of NRT, but not of computer‐generated tailored advice.

Conclusion  Computer‐generated tailored advice did not enhance telephone counselling, nor have any independent effect on cessation. This may be due to poor timing of the computer‐generated tailored advice and poor integration of the two modes of advice.
Maternal drug use and length of neonatal unit stay
Authors: Johnson K. , Greenough A. , Gerada C.
Published: May 2003

Aims  Infants with neonatal abstinence syndrome (NAS) may require a prolonged neonatal unit admission, which has implications for both their families and bed occupancy. The aim of this study was to test the hypothesis that the duration of neonatal unit stay would be influenced by the type of maternal drug use and particularly prolonged for the infants whose mothers had taken methadone with other substances.

Design  The medical records of infants born at term who were admitted consecutively to a neonatal unit because of NAS were reviewed. Data were collected regarding antenatal and neonatal factors likely to affect neonatal stay. Comparisons were then made between three groups of infants: those whose mothers took methadone alone, methadone plus other drugs or non‐methadone opioids.

Setting  Level three neonatal intensive care unit.

Participants  Forty‐one infants with a median gestational age of 39 (range 37–42) weeks.

Findings  The 41 infants had a median duration of admission of 30 (range 3–68) days. Thirty‐six of the infants required treatment for NAS; their median duration of treatment was 29 (range 6–68) days. The duration of stay and requirement for treatment were greater in the infants exposed to methadone and other drugs compared to those exposed to non‐methadone opiods only (P = 0.0212, P = 0.0343, respectively). The duration of stay without requirement for treatment was also longest in the methadone plus other drugs group (P = 0.0117).

Conclusions  Prolonged treatment and neonatal unit stay are influenced by the type of maternal drug abused.
Eye movements to smoking‐related pictures in smokers: relationship between attentional biases and implicit and explicit measures of stimulus valence
Authors: Mogg Karin , Bradley Brendan P. , Field Matt , De Houwer Jan
Published: May 2003

Aims  To investigate biases in overt orienting of attention to smoking‐related cues in cigarette smokers, and to examine the relationship between measures of visual orienting and the affective and motivational valence of smoking cues.

Design  Smokers and non‐smokers took part in a single session in which their attentional and evaluative responses to smoking‐related and matched control pictures were recorded.

Participants  Twenty smokers and 25 non‐smokers.

Measurements  Direction and duration of gaze was measured while participants completed a visual probe task. Subjective and cognitive‐experimental measures of the motivational and affective valence of the stimuli were recorded.

Findings  Smokers, but not non‐smokers, maintained their gaze for longer on smoking‐related pictures than control pictures. They were also faster to detect probes that replaced smoking‐related than control pictures, consistent with an attentional bias for smoking‐related cues. Furthermore, smokers showed greater preferences for smoking‐related than control pictures, compared with non‐smokers, on both the subjective (explicit) and cognitive‐experimental (implicit) indices of stimulus valence. Within smokers, longer initial fixations of gaze on smoking‐related pictures were associated with a bias to rate the smoking pictures more positively, with greater approach tendencies for smoking pictures on the cognitive‐experimental task, and with a greater urge to smoke.

Conclusions  These results demonstrate that smokers show biased attentional orientating to smoking cues, which is related to craving and the affective and motivational valence of the stimuli.
Characteristics of non‐respondents in a US national longitudinal survey on drinking and intimate partner violence
Authors: Caetano Raul , Ramisetty‐Mikler Suhasini , McGrath Christine
Published: May 2003

Aims  To identify non‐respondents’ characteristics in a longitudinal household survey of intimate partner violence and drinking among United States couples.

Design  Multistage probability sampling procedure with over‐samples from black and Hispanic populations. A total of 1635 couples 18 years of age or older were interviewed at baseline (1995) for a response rate of 85%. Five years later, 1392 respondents were re‐interviewed, with a response rate of 72%.

Measurements  Sociodemographic variables, drinking volume and pattern, drug use, intimate partner violence, exposure to parental violence and childhood physical abuse.

Findings  Among men, those who are younger, those who did not graduate from high school, those who are unemployed and those who are drinkers are more likely to be among the non‐respondents. Among women, those who are 40–49 years of age are two times more likely than those aged 50 years or older to be among non‐respondents. Also, women who reported experiencing abuse during their childhood are less likely to be among non‐respondents compared with those who were not victimized. Gender‐specific regression models accounted for only 5% of the variance in the response status variable, even after the inclusion of a comprehensive range of predictors in the model.

Conclusions  A low proportion of the variance in survey participation was explained by the variables included in the analysis, suggesting that sociodemographic, drinking‐related and violence‐related variables might not be the main factors determining participation in the survey.
Sex differences in the effects of stressful life events on changes in smoking status
Authors: McKee Sherry A. , Maciejewski Paul K. , Falba Tracy , Mazure Carolyn M.
Published: May 2003

Aims  Stressful life events known to be associated with substance use were examined to determine if there were sex‐specific responses to stress resulting in changes in smoking status.

Participants and measurements  A community‐based sample of ever smokers from the Americans’ Changing Lives study (n = 1512, 45% female based on sample weights) was used to examine the interactive effects of sex and stressful life events on the likelihood of two outcomes; relapse among former smokers and failure to quit among current smokers. Logistic regression procedures were used to calculate odds ratios. Factors known to be associated with smoking status (e.g. depression, self‐esteem, social support) were assessed as control variables.

Findings  In the sample of former smokers (n = 729) interpersonal loss events were associated with continued abstinence, whereas change of residence and adverse financial events were associated with increased occurrence of relapse. Women were more likely than men to relapse in response to a financial event. In the sample of current smokers (n = 783), financial events were associated with continued smoking, whereas health events were associated with increased likelihood of quitting. Women were more likely than men to continue smoking in the presence of an adverse financial event and less likely than men to quit in response to an adverse health event.

Conclusions  Overall, stressful life events appear to have a greater deleterious effect on continued abstinence and the ability to quit smoking for women when compared to men. In particular, health and financial events are important risk factors for women and tobacco use.
Prevalence of alcohol use disorders and associated factors: a population‐based study using AUDIT in southern Brazil
Authors: Mendoza‐Sassi Raúl A. , Béria Jorge U.
Published: May 2003

Aims  To assess the prevalence of potential alcohol use disorders and associated factors using the Alcohol Use Disorders Identification Test (AUDIT).

Design  Cross‐sectional study.

Setting  A town in southern Brazil.

Participants  A representative sample of 1260 people aged 15 and over.

Measurements  Demographic, socioeconomic, smoking habit and mental health data were collected. Logistic regression was used in the multivariate analysis, and odds ratios (ORs) and 95% confidence intervals (CIs) were calculated.

Findings  Overall prevalence of alcohol use disorder was 7.9%, with 14.5% prevalence among men and 2.4% among women. The risk of alcohol misuse increased across social class (P linear trend = 0.03) and compared with the highest classes (A and B), groups C through E had ORs of 1.48, 1.51 and 2.36, respectively. Males had an OR of 6.89 (CI 3.61–13.16) compared with women. A linear trend was found (P = 0.001) between smoking categories, and smokers (OR 3.27; CI 1.91–5.58) and ex‐smokers (OR 1.30; CI 0.56–2.98) were at higher risk than non‐smokers. Those with minor psychiatric disorders had a 2.48 OR (CI 1.35–4.56) of presenting a positive test.

Conclusions  The AUDIT detected a high prevalence of potential alcohol use disorders in the population sampled. Those identified are potential targets for preventive measures implemented through health policies.
Lowering of interstitial fluid pressure in rat trachea after substance P alone and in combination with calcitonin gene‐related peptide
Authors: Gjerde E.‐A. B. , Karlsen T. V. , Reed R. K.
Published: May 2003

Neurogenic inflammation is mediated following a release of sensory neuropeptides including calcitonin gene‐related peptide (CGRP) and substance P (SP). The release of peptides can be mediated chemically with capsaicin, or electrically by stimulation of the vagal nerve, both inducing vasodilation, plasma protein extravasation and lowering of interstitial fluid pressure (Pif) which will contribute to the enhancement of oedema formation.

Aim: Lowering of Pif has previously been demonstrated following intravenous (i.v.) treatment with CGRP, but it was not possible to demonstrate that SP had this effect under the same condition.

Methods: Micropuncture measurements of Pif in the submucosa, without opening of the trachea, was conducted on rats anaesthetized with pentobarbital sodium (50 mg kg−1) and cardiac arrest was induced with i.v. KCl.

Results: P
if in vehicle‐treated animal averaged −1.7 ± 0.4 (SD) mmHg (n = 9). Intravenous injection of SP induced significant lowering of Pif compared with control, both at low dose (0.47 nmol kg−1 body weight) with 1 min distribution time (P < 0.007, −4.2 ± 2.3 mmHg) and at high dose with seconds of distribution time (P < 0.03, −4.2 ± 1.6 mmHg). The same response was observed after treatment with SP co‐injected with CGRP.

Conclusions:  Substance P alone or in combination with CGRP is able to induce a rapid lowering of Pif showing that this peptide is a potent agent in increasing the hydrostatic driving pressure initially transporting fluid into the tissue during an acute inflammatory reaction.
Ischaemic preconditioning alters the energy metabolism and protects the ischaemic myocardium in a stepwise fashion
Authors: Kavianipour M. , Ronquist G. , Wikström G. , Waldenström A.
Published: May 2003

Aims and Methods: Recently it was suggested that ischaemic preconditioning (IP) protects the myocardium in a graded pattern as assessed by myocardial infarct size estimation. Using tissue biopsies we investigated the impact of the proposed graded pattern of protection on myocardial energy state in an open‐chest porcine model of IP with either one (1xIP) or four (4xIP) episodes of preconditioning. Furthermore, we evaluated the relationship between interstitial energy‐related metabolite levels obtained by the microdialysis technique and the degree of subsequent ischaemic insult.

Results: During the long ischaemia the difference between pre‐ischaemic and post‐ischaemic total adenylate pools and the sum of adenylate breakdown products (adenosine, inosine and hypoxanthine) as well as tissue lactate levels appeared as follows: non‐IP > 1xIP > 4xIP (P < 0.05). Moreover interstitial peak levels of lactate, hypoxanthine and taurine displayed a graded pattern analogous to the development of ischaemic damage, where non‐IP > 1xIP > 4xIP.

Conclusions: We present for the first time concordant energy metabolic and morphometric data in support of IP being a stepwise phenomenon for protection of the ischaemic myocardium. Furthermore, IP resulted in proportionally higher levels of hypoxanthine (relative to inosine) in the ischaemic myocardium, suggesting a different handling of adenine nucleotide breakdown products in the IP myocardium.
Oxygen dependency of the adrenergic Na/H exchange in rainbow trout erythrocytes is diminished by a hydroxyl radical scavenger
Authors: Nikinmaa M. , Bogdanova A. , Lecklin T.
Published: May 2003

Aim: Potassium transport via the potassium chloride cotransporter in rainbow trout erythrocytes is increased by high oxygen tension. It appears that the effect of oxygen is mediated by reactive oxygen species, especially hydroxyl radicals. In contrast, the activity of adrenergically stimulated sodium proton exchange decreases with increasing oxygen tension. As available data suggest that the two transporters are regulated reciprocally, the present study was undertaken to evaluate, if hydroxyl radicals may inhibit sodium transport via the adrenergically stimulated sodium proton exchanger.

Methods: The effects of the hydroxyl radical scavenger, 2 mm mercaptopropionyl glycine (MPG), on the activity of the adrenergically activated sodium proton exchange in rainbow trout erythrocytes were examined by measuring unidirectional sodium flux, using radioactive isotope, and cellular water content.

Results: The activity of the sodium proton exchange increased with decreasing oxygen tension after adrenergic stimulation. When MPG was present during incubation, there was no statistically significant effect of oxygen tension on the adrenergically stimulated sodium proton exchange, whereby the activity of the transporter at atmospheric oxygen tension was markedly higher in the presence than in the absence of MPG. In the absence of adrenergic stimulation, MPG did not influence the transporter activity significantly at any oxygen tension.

Conclusion: The data suggest that hydroxyl radicals are involved in the inhibition of the adrenergically stimulated sodium proton exchange at elevated oxygen tensions.
Interaction of fibre type, potentiation and fatigue in human knee extensor muscles
Authors: Hamada T. , Sale D. G. , MacDougall J. D. , Tarnopolsky M. A.
Published: May 2003

Aim: To examine the effect of fibre type on potentiation and fatigue.

Methods: Young men (n = 4 per group) with a predominance of type I [61.4 ± 6.9% (SD), group I (GI)] or type II [71.8 ± 9.2%, group II (GII)] fibres in vastus lateralis, performed a fatigue protocol of sixteen 5‐s maximal voluntary isometric contractions (MVCs) of the right knee extensors. Maximal twitches and corresponding muscle action potentials (M‐waves) were evoked before the first MVC, during the 3‐s rest period after each MVC and at intervals during the 5‐min recovery period after the last MVC.

Results:  Group II [49.3 ± 2.6% (SE)] had a greater decrease in MVC force than GI (22.8 ± 6.2%) during the fatigue protocol. Group II (126.4 ± 13.6%) showed greater twitch force potentiation early in the fatigue protocol than GI (38.2 ± 2.3%), but greater depression at the end (33.7 ± 13.7% vs.17.4 ± 3.4%). Twitch time‐to‐peak torque (TPT) and half relaxation time (HRT) initially decreased but then increased as the fatigue protocol progressed; GII had a greater increase in HRT. During a 5‐min recovery period twitch force increased above the prefatigue level and remained so until the end of the recovery period; the pattern was similar in GI and GII. Twitch TPT and HRT remained elevated during recovery. M‐wave area increased throughout the fatigue protocol and the first part of recovery before returning to baseline values in GII, whereas there were no significant changes in GI. The interaction between potentiation and fatigue was amplified in GII early in the fatigue protocol with concurrently greater twitch and M‐wave potentiation, and greater MVC force decrease and HRT increase. Late in the protocol, GII had a greater decrease in twitch and MVC force combined with greater M‐wave potentiation.

Conclusion: It is concluded that fibre type distribution influences potentiation and fatigue of the twitch, and potentiation of the M‐wave during fatiguing exercise.
Dose‐dependent effects of acute exercise on PKC levels in rat heart: is PKC the heart's prophylactic?
Authors: Carson L. D. , D. H. Korzick
Published: May 2003

Epidemiological studies have demonstrated that chronic exercise is cardioprotective, and recent evidence from our laboratory suggests a key role for protein kinase C (PKC)‐dependent pathways, at least in part, as a cellular basis for this response. However, the dose–response relationship linking exercise volume and the time course of isoform‐specific PKC activation are poorly understood.

Aim:  The purpose of this investigation was to determine the effects of acute exercise of varying durations on PKC subcellular distribution and phosphorylation in the rat left ventricle.

Methods:  Adult (5 months) male Fischer‐344 more rats were subjected to a single bout (OB) or 7 days (SB) of treadmill running (n = 6/group; 23 m min−1, 20 min), and compared with sedentary controls (SED; n = 8). Hearts were isolated immediately after [early window (EW); n = 3/group] or 24 h after the last exercise bout [late window (LW); n = 3/group] in OB and SD, respectively. Total PKC and subcellular distribution for the α, δ, ɛ, βI, and βII isoforms, as well as phosphorylated (phospho‐) PKCɛ (pSer729), PKCα (pSer657) and PKCδ (pThr507) levels were assessed by western blotting. Protein kinase Cɛ and PKCα mRNA levels were assessed by real time polymerase chain reaction.

Results: Following OB, PKCβI protein levels were reduced, while total phospho‐PKCɛ (pSer729), PKCα (pSer657) and PKCδ (pThr507) levels were increased during EW (P < 0.05). Interestingly, total PKCδ (31%) and membrane‐associated PKCα (24%) levels decreased from EW to LW (P < 0.05). In contrast, SB yielded chronic increases in total PKCɛ (80.5%) levels and PKCδ (20.0%) levels (P < 0.03), with reversal of effects on phospho‐PKCɛ (Ser729), phospho‐PKCα (Ser657) and phospho‐PKCδ (Thr507) levels observed with OB. Reductions in total phospho‐PKCα (Ser657) persisted at SB (26.1%; P < 0.02). Interestingly, mRNA levels for PKCɛ were significantly increased following SB while PKCα mRNA levels were reduced, respectively.

Conclusion:  These data suggest that divergent patterns of PKC activation occur following OB and SB at both the transcriptional and translational levels. That similar patterns of PKC translocation are observed in experimental models of ischaemic preconditioning and genetic PKC manipulation provide evidence for a dose‐dependent cardioprotective phenotype induced by physical activity.
Age, cell signalling and cardioprotection
Authors: Taylor R. P. , Starnes J. W.
Published: May 2003

For many years investigators have been researching methods of preconditioning the myocardium against ischaemia‐induced damage; however, a majority of this research has been carried out in young animals and cells. Normal ageing is accompanied by changes in the human myocardium that decrease its capacity to tolerate and respond to various forms of stress. Also, the likelihood of experiencing an ischaemic stress and other cardiovascular complications increases as an individual ages; therefore, an aged population would benefit most from cardioprotective treatments. Methods currently known to provide cardioprotection (or preconditioning) include exercise, heat stress, oxidative stress, brief ischaemia, stretch and certain pharmacological interventions. It is unclear whether the aged myocardium can adapt to a preconditioning stimulus; however, many researchers have observed age‐related alterations in the expression and activation of proteins key to the cardioprotective process. These proteins include heat shock protein 70 (HSP70), nitric oxide synthase (NOS), the sodium‐hydrogen exchanger (NHE), and the mitogen‐activated protein (MAP) kinases c‐Jun N‐terminal Kinase (JNK), extracellular signal‐regulated kinase (ERK), and p38. Therefore, the purpose of the current review will be to outline the current knowledge of these cardioprotective agents in an aged myocardium. Interactions among the cardioprotective agents outlined herein suggest that age‐related changes in the myocardium will need to be better understood before cardioprotective interventions that have been proved effective in young animals can be applied to an aged human population.
Phorid parasitoids affect foraging activity ofSolenopsis richteriunder different availability of food in Argentina
Authors: Folgarait Patricia J. , Gilbert Lawrence E.
Published: May 2003

1. In Argentina, six species ofPseudacteonparasitoids (Phoridae) attackSolenopsis richteri, one of the two species of South American fire ant that are exotic pests in North America.

2. The presence of thesePseudacteonspecies significantly reduces the number of ants at food resources in the field, as well as foraging activity generally.

3. SomePseudacteonnot only attack ants walking on trails or at feeding sites, but also at mound entrances, inhibiting workers from leaving to forage.

4. The average size of foraging ants (which prescribes their suitability as hosts) decreased in the presence of phorids.

5. The number of attacking phorids was correlated positively with the number of ants walking towards the food on the trail before the attack.

6.Solenopsis richteriworkers responded to manipulations of food size and presence or absence of parasitoids in a risk‐adjusting way, i.e. although more foragers were recruited to larger food items, attacking phorids reduced ant foraging activity by the same factor regardless of the size of the food offered.

7. The data suggest thatS. richtericolonies juggle the needs to harvest food efficiently, reduce competition, and avoid excess risks from parasitoids in complex ways.