bluuebunny/crossref_metadata_2025 huggingface dataset:
Dynamic Changes of the Immunoglobulins in Patients with Severe Ovarian Hyperstimulation Syndrome: Efficacy of a Novel Treatment Using Peritoneo‐Venous Shunt
Authors: TAKAMIZAWA SATORU , SHIBAHARA HIROAKI , TANEICHI AKIYO , OBARA HIROMI , FUJIWARA HIROYUKI , OGAWA SYUICHI , KOIKE TOSHIMITSU , IDEI SADAYOSHI , SATO IKUO
Published: March 2003

PROBLEM: To evaluate the efficacy of continuous auto‐transfusion system of ascites (CATSA) for the treatment of patients with severe ovarian hyperstimulation syndrome (OHSS) at the risk of febrile morbidity, the dynamic changes of immunoglobulins in the sera and the peritoneal fluid from patients with severe OHSS treated by CATSA were estimated.

METHOD OF STUDY: Ten patients with severe OHSS after superovulation for in vitro fertilization‐embryo transfer (IVF‐ET) were treated by CATSA. Immunoglobulin concentrations were examined in the serum and in the peritoneal fluid before and after CATSA. As controls, serum samples from 15 infertile women, who did not develop OHSS after the same superovulation protocol, were obtained on the day of mid‐luteal period (Control‐1). Serum samples from 15 patients with OHSS, who were treated by albumin infusion without paracentesis, were also obtained before and after the treatment (Control‐2).

RESULTS: Before the treatments, serum immunoglobulin G (IgG) concentrations in patients with severe OHSS treated with CATSA and those in patients of Control‐2 were significantly lower than those in patients of Control‐1 (P < 0.01). Following CATSA, the concentration of IgG increased in the sera, while it decreased in the peritoneal fluid.

CONCLUSIONS: Serum IgG in patients with severe OHSS exuded into their peritoneal cavity, indicating that they might be at the status of immunodeficiency and at the risk of febrile morbidity. However, non‐infectious febrile morbidity attributed to endogenous pyrogenic mechanism might be considerable. It is also suggested that CATSA might be effective in improving hypoimmunoglobulinemia of the patients with severe OHSS by the peritoneo‐venous shunt.
Peri‐partum Changes in the Intraepithelial Lymphocyte Population of Sheep Interplacentomal Endometrium
Authors: NASAR MD. ABU , RAHMAN AMINOOR , MEEUSEN ELS N.T. , LEE CHEE SEONG
Published: March 2003

PROBLEM: Previous studies have shown that the proportion of γδTCR+ large granulated lymphocytes (LGLs) increased markedly during pregnancy and declined dramatically by 2 days after parturition in sheep interplacentomal uterine epithelium. In the present study, the distribution, dynamics and fate of these cells, just before, during and immediately after parturition are described.

METHODS OF STUDY: Interplacentomal tissues were collected at 140 days post‐coitus (dpc), 148 dpc, during parturition, 1–2 hr postpartum, 1 day postpartum (dpp) and 3 dpp, and were studied using light and electron microscopy, and immuno histochemistry. Uterine washings were collected at 148 dpc and examined for the presence of LGLs. Semi‐thin Araldite sections taken at different stages were used to quantify the intraepithelial LGLs, non‐granulated lymphocytes (NGLs) and apoptotic cells, whereas frozen sections were used to quantify CD45R+, CD8+ and γδTCR+ intraepithelial lymphocytes (IELs).

RESULTS: A dramatic decline in the proportion of IELs in the luminal epithelium during parturition was observed, mainly because of the decline in CD45R+, CD8+ and γδTCR+ IELs. There was also a significant decline in the number of granules/LGL at parturition. This was accompanied by the presence of apoptotic cells of which some were LGLs. The proportions of IELs, LGLs and apoptotic cells markedly increased at 3 dpp. LGLs were found both in uterine washings at 148 dpc and in the uterine lumen at 3 dpp. Apoptosis of glandular epithelial cells was also evident at parturition and markedly increased at 1 dpp.

CONCLUSIONS: Our results demonstrated that the dramatic decline in the proportion of γδTCR+ LGLs at parturition was because of de‐granulation, apoptosis and migration of these cells into the uterine lumen.
Effect of Active Immunization with the C‐terminal 67–94 (R‐28) Region of Human Seminal Plasma Inhibin on the Fecundity of Adult Male Rabbits
Authors: Mehta Monica N. , Mahale Smita D. , Iyer K.S. , Vanage Geeta R. , Raghavan Vijaya P. , Moodbidri Sudhir B.
Published: March 2003

PROBLEM: To characterize the specificity of antibodies to the synthetic C‐terminal 67–94 (R‐28) peptide of human seminal plasma inhibin (hSPI), and to examine the effect of active immunization on the fecundity of adult male animals.

METHOD OF STUDY: The specificity of R‐28‐DT antibodies was tested using enzyme‐linked immunosorbent assay, immunohistochemical and immunofluorescence staining, and Western blotting. For fertility studies, adult male rats and rabbits were immunized and mated with females of the same strain.

RESULTS: Rabbit antibodies to R‐28‐DT recognized native hSPI, as demonstrated by sperm agglutination in vivo and in vitro, on the sperm head by immunofluorescence staining, and in the columnar epithelial cells of the prostate by immunohistochemical staining. Immunization with the R‐28‐DT conjugate elicited a poor antibody response in male rats and their fecundity remained unaffected, while in male rabbits it elicited a good immune response with reduction in their fertility.

CONCLUSION: R‐28‐DT antibodies recognized the native hSPI in the prostatic epithelium and agglutinated washed rat, rabbit, monkey, and human spermatozoa in vitro. Immunization of rabbits caused agglutination of spermatozoa resulting in a decrease in their fecundity. The conjugated R‐28 peptide of hSPI offers promise as a male contraceptive.
Microsurgical instruments for root‐end cavity preparation following apicoectomy: a literature review
Authors: Von Arx T. , Walker W. A.
Published: March 2003

Abstract – Root‐end cavities have traditionally been prepared by means of small round or inverted cone burs in a micro‐handpiece. Since sonically or ultrasonically driven microsurgical retrotips became commercially available in the early 1990s, this new technique of retrograde root canal instrumentation has been established as an essential adjunct in periradicular surgery. At first glance, the most relevant clinical advantages are the enhanced access to root ends in limited working space and the smaller osteotomy required for surgical access because of the various angled designs and small size of the retrotips. However, a number of experimental studies comparing root‐end preparations made with microsurgical tips to those made with burs have demonstrated other advantages of this new technique, such as deeper cavities that follow the original path of the root canal more closely. The more centered root‐end preparation also lessens the risk of lateral perforation. In addition, the geometry of the retrotip design does not require a beveled root‐end resection for surgical access thus decreasing the number of exposed dentinal tubules. A controversial issue of sonic or ultrasonic root‐end preparation is the formation of cracks or microfractures, and its implication on healing success. The present paper reviews experimental and clinical studies about the use of microsurgical retrotips in periradicular surgery and discusses many issues raised in previous papers.
Impact strength of teeth restored by fragment‐bonding
Authors: Farik B. , Munksgaard E. C. , Andreasen J. O.
Published: March 2003

Abstract – The objective of this in vitro study was to investigate the impact strength of anterior teeth that have been fractured and restored by bonding with a dentin‐bonding agent and a composite resin. Twenty sheep central incisors were divided into two groups, 10 in each. One group (intact teeth) served as the control and the teeth in the other group were fractured and then bonded with a bonding agent and a low‐viscous composite resin. The specimens were tested in a modified impact‐testing machine (pendulum type). The mean impact strength of the intact teeth was 30.6±2.16 KJ/m2 and of the bonded teeth was 30.2±1.86 KJ/m2. Statistics revealed that the two means were not significantly different. The results related well with the fracture strength obtained by loading intact and bonded teeth at constant but low speed until fracture. It was concluded that bonding fragments to the remaining tooth structure may restore the tooth to its original strength, measured at modest velocities of the applied force. In other words, reattaching the original coronal fragment of traumatised fractured anterior teeth restored with One‐Step dentin bonding system and Æliteflo composite resin would withstand a second trauma to the same extent as intact teeth.
Revascularization of an immature permanent tooth with apical periodontitis and sinus tract
Authors: Iwaya Shin‐ichi , Ikawa Motohide , Kubota Minoru
Published: March 2003

Abstract – A necrotic immature mandibular second premolar with periapical involvement in a 13‐year‐old patient was treated. Instead of the standard root canal treatment protocol and apexification, antimicrobial agents were used in the canal, after which the canal was left empty. Radiographic examination showed the start of apical closure 5 months after the completion of the antimicrobial protocol. Thickening of the canal wall and complete apical closure was confirmed 30 months after the treatment, indicating the revascularization potential of a young permanent tooth pulp into a bacteria‐free root canal space.
Effect of enamel matrix derivative (EMDOGAIN®) upon periodontal healing after replantation of permanent incisors in Beagle dogs
Authors: Iqbal Mian Khalid , Bamaas Najat
Published: March 2003

Abstract – This study histologically assessed the effect of enamel matrix derivative (EMDOGAIN®) on periodontal healing in re‐implanted teeth in nine Beagle dogs. Incisors in dogs were re‐implanted after 15, 30 and 60 min of dry storage with and without the application of EMDOGAIN. The pulps were removed in all teeth. In groups 1 and 2, dog teeth were splinted and the dogs sacrificed after 8 and 12 weeks, respectively. In group 3, dog teeth were not splinted and sacrifice took place after 12 weeks. The histological parameters studied were healed PDL, surface, inflammatory and replacement resorption. Univariable and multivariable analysis of data was performed. Increased incidence of healed PDL was inversely proportional to extraalveolar time. No significant differences were noticed between splinted and non‐splinted teeth. The EMDOGAIN group showed a higher incidence of healed PDL, while controls showed a higher incidence of ankylosis. The effect of EMDOGAIN was more pronounced at the 12‐week interval.
Traumatic injuries to anterior teeth among schoolchildren in Malaysia
Authors: Nik‐Hussein Nik Noriah
Published: March 2003

Abstract – Evidence of traumatized permanent incisors was recorded as part of a national oral health survey of schoolchildren in Malaysia. A total of 4085 schoolchildren aged 16 years were examined. The prevalence of injury was 4.1% and it was significantly higher in males than females, with a ratio of 2:1. Almost 75% of the subjects had one tooth affected. Out of a total of 200 fractured teeth, 78.0% involved the maxillary central incisors. A high level of untreated traumatized teeth (89%) was noted. However, of the untreated traumatized teeth, only 9% presented with problems such as discoloration of tooth, sinus or abscess formation.
Factors affecting the time of onset of resorption in avulsed and replanted incisor teeth in children
Authors: Donaldson M. , Kinirons M. J.
Published: March 2003

Abstract – Resorption is the main reason for loss of replanted teeth. The outcome examined in this study is the timing of the onset of resorption. The effect of dichotomised dry and wet time intervals as well as the presence of additional crown damage and of contamination were determined. Of 84 replanted teeth, 67.5% developed resorptions. Twenty‐eight had detectable additional crown damage with a more rapid onset being seen in these cases (P=0.009). The critical limit for dry time was 15 min (P=0.038) and significant differences persisted for greater limits also. Serial analysis of the association between the time of onset of root resorption and dichotomised wet time variables failed to yield any significant associations. There was visible contamination detected in 32 teeth and these exhibited a more rapid onset of resorption than the other cases (P=0.030). Teeth with inflammatory root resorption (12.8%) had a more rapid onset of resorption than those that developed replacement resorption (54.7%) (P<0.001). It is concluded that the risk of early resorption is increased in teeth that have additional damage or have contamination, or are kept in dry conditions for longer than 15 min.
Prevalence of fractured incisal teeth among children in Harris County, Texas
Authors: Alonge Olusegun K. , Narendran Sena , Williamson Dan D.
Published: March 2003

Abstract – Trauma to the teeth is a common reason for emergency room visits among children, with the maxillary anterior teeth being mostly affected. The consequences of dental trauma include disfigurement, speech defects and psychological effects. This is a cross‐sectional study comprising 1039 students, with 47% being males and 53% females. Teeth were examined for physical evidence of trauma. The prevalence of incisal fracture was 2.4% with no significant gender difference (2.9% and 2.0% among males and females, respectively). The male to female prevalence ratio was 1.45 to 1.0. The maxillary incisors accounted for 96% of fractured teeth. Among children with traumatized incisors, 86% had one tooth affected, while 14% had two traumatized teeth. The prevalence of incisal trauma was significantly higher among children of low socioeconomic status (χ2=5.86, P=0.02, df=1). Though African American and Hispanic children had higher prevalence than White children, the differences were not statistically significant. The study reports a low prevalence of incisal trauma among Harris County children and a socioeconomic difference. This study recommends further investigation of incisal trauma in this region as well as educational programs to prevent dental trauma.
Autotransplantation of teeth: requirements for predictable success
Authors: Tsukiboshi Mitsuhiro
Published: March 2003

Abstract –  The aim of this article is to summarize the biologic principles required for successful autotransplantation of teeth. Indications, armamentarium, technique and prognosis will be discussed.
Marker‐assisted selection of a neuro‐behavioural trait related to behavioural inhibition in the SHR strain, an animal model of ADHD
Authors: Mormède P. , Moneva E. , Bruneval C. , Chaouloff F. , Moisan M.‐P.
Published: March 2003

The search for the molecular bases of neuro‐behavioural traits in Spontaneously Hypertensive Rats (SHR), an animal model of Attention Deficit Hyperactivity Disorder (ADHD), led to the discovery of two quantitative trait loci related to the locomotor activity in the centre of the open field. In the present study, rats from an F2 intercross between the SHR and Lewis strains were selected with markers on the basis of their genotype at these two loci. We obtained a ‘high line’ in which rats have the alleles increasing the trait, and a ‘low line’ with the lowering alleles. In activity cages with a dim light, the low line was more active than the high line. The reverse was found in the open field, and the inhibition of locomotor activity in the low line (as compared to the high line) was directly related to the aversiveness of the situation (larger in the centre than in the periphery, and in high light than in low light), and was more intense in males than in females. This inhibition is not attributable to a classical ‘anxiety’ factor as measured in the elevated plus maze, in which the open arms behaviours were not different between the lines. The high line also showed a deficit in prepulse inhibition of the acoustic startle reflex. The present data show that the two loci previously described in a SHR × Lewis intercross as related to the activity in the centre of the open field are indeed involved in a behavioural inhibition trait. The marker‐based selected lines described here are unique tools for the study of the neurobiological bases of this trait and the molecular foundations of its variability of genetic origin.
Strain and sex differences in repeated ethanol treatment‐induced motor activity in quasi‐congenic mice
Authors: Sershen H. , Hashim A. , Vadasz C.
Published: March 2003

The B6.C quasi‐congenic Recombinant QTL Introgression (RQI) strains of the b4i5 series have similar genetic background, but differ in about 5% of their genome from the C57BL/6ByJ (B6) background strain because they carry short chromosome segments introgressed from the BALB/cJ (C) donor strain. These RQI strains were derived from mouse lines selectively bred for high activity of mesencephalic tyrosine hydroxylase (TH/MES), therefore genetic variation in dopamine system‐related behaviours, such as ethanol‐induced motor activity, can be expected. Males and females of 17 RQI and two progenitor strains were tested for initial motor activity for 15 min after a habituating injection of saline, which was followed by an i.p. injection of saline or ethanol (2 g/kg) and an additional test of motor activity for 30 min. This procedure was repeated during 4 subsequent days. In all strains, the first‐day ethanol treatment showed an inhibitory effect. With repetition of the treatment the inhibitory effect decreased, and a stimulatory effect could be observed with significant strain‐ and sex‐dependent variation. Females exhibited higher activity in the saline group than males, and reached an equilibrium of inhibition and stimulation sooner than males with repetition of the ethanol treatment. The highest (> 25‐fold) difference in activity after repeated ethanol treatment was detected between females of the two strains B6.Cb4i5‐Alpha4/Vad and B6.Cb4i5‐Beta13/Vad. These results firstly suggest that females are more sensitive to repeated ethanol exposure than males, secondly they support the observations that ethanol has both inhibitory and stimulatory effects on motor activity, which are affected by sex, genotype, and repetition of treatment, and thirdly offer new quasi‐congenic animal models with highly different responses to ethanol allowing one to more quickly move to gene detection.
Enriched early experiences of mice underexpressing the β‐amyloid precursor protein restore spatial learning capabilities but not normal openfield behavior of adult animals
Authors: Tremml P. , Lipp H.‐P. , Müller U. , Wolfer D. P.
Published: March 2003

We have previously reported severely impaired spatial learning in mutant mice underexpressing a shortened variant of the β‐amyloid precursor protein (β‐APP∂/∂). This targeted mutation is functionally equivalent to a null mutation. It also disturbs behavioral and neurological maturation with deficits emerging mainly between postnatal day (pd) 11 and 19. Such early tested mice exhibited almost no genotype‐related difference in Morris water maze learning, raising the possibility that early handling might have compensated for genetic deficits. To verify this effect, we compared watermaze learning and open field behavior of 66 adult mutant and wildtype mice having been handled during pd 3–27 with that of 70 non‐handled mutant and wildtype mice. Neurological testing during pd 3–27 markedly reduced time near wall and improved spatial retention of adult mutants, restoring their learning capabilities to wildtype levels. Early handling did not cure the mutation associated activity deficit in the open field, but mainly increased center field exploration in both mutants and wildtypes. In a follow‐up experiment we analyzed whether an early (pd 3–10, n= 22) or middle (pd 11–19, n= 24) period of handling in form of neurological testing had differential effects on adult behavior. Mice handled during pd 11–19 had slightly shorter escape times than mice handled during pd 3–10 but were not significantly different in other behavioral measures. There were no sex related differences. Correlational and factor analysis showed that both the mutation and early handling had pleiotropic behavioral effects, resulting in differentially impaired mutants depending on the test situation. Likewise, early handling affected not only thigmotactic tendencies but also, more subtly, other behavioral components underlying water maze learning. We conclude that early postnatal stimulation can prevent mutation induced learning deficits in adult mice, but probably through other developmental mechanisms than those affected by the mutation. This implies that some behavioral impairments related to β‐APP malfunction may be corrected through simple treatments.
Absence of anxiolytic response to chlordiazepoxide in two common background strains exposed to the elevated plus‐maze: importance and implications of behavioural baseline
Authors: Rodgers R. J. , Davies B. , Shore R.
Published: March 2003

Although genetic background is acknowledged as a potentially important determinant of mutant phenotypes, publications on genetically modified mice far outnumber those on progenitor strains. We have recently reported major differences in basal anxiety levels (elevated plus‐maze & light/dark exploration) among three strains (C57BL/6JOlaHsd, 129/SvEv and 129S2/SvHsd) employed as progenitor stock in European laboratories (Rodgers et al. in press). Furthermore, the phenotypes of these inbred strains differed significantly from that of an outbred strain (Swiss‐Webster) commonly used in behavioural pharmacology. In view of these findings, the present study assessed possible differences in the anxiolytic efficacy of chlordiazepoxide (0, 7.5 & 15.0 mg/kg, IP) in three of these strains (Swiss‐Webster (SW), C57BL/6JOlaHsd (C57) & 129S2/SvHsd (129)). Experimentally naive mice were exposed to the elevated plus‐maze, sessions were videotaped and behaviour analysed using ethological software. The performance of control subjects confirmed significant strain differences in basal levels of activity (SW > C57 > 129) and anxiety‐related behaviours (129 = SW > C57), with hypolocomotion dominating the 129 profile. SW mice displayed an anxioselective response to both doses of chlordiazepoxide (CDP), with significant reductions in open arm avoidance and risk assessment observed in the absence of any change in general activity. In direct contrast, the lower dose of CDP (7.5 mg/kg) was without effect in either inbred strain, whereas treatment with 15.0 mg/kg induced a profile indicative of muscle relaxation/mild sedation in C57 mice and virtually abolished all behavioural activity in 129 mice. Although the absence of an anxiolytic response to CDP in C57 mice may be attributed to their low basal anxiety levels, the profile of 129 mice strongly suggests an abnormality in benzodiazepine/GABAA receptor function. The implications of these findings for research on mutant mice are discussed.
Delivery of singleton preterm infants in New South Wales, 1990–1997
Authors: Roberts Christine L. , Algert Charles S. , Raynes‐Greenow Camille , Peat Brian , Henderson‐Smart David J.
Published: March 2003

Objective: To examine trends in the maternal characteristics and delivery of singleton preterm infants in an Australian population.

Design: Population‐based descriptive study.

Setting: New South Wales (NSW), Australia.

Population: The population included 37 500 singleton preterm births from 1 January 1990 to 31 December 1997.

Methods: Data were obtained from the NSW Midwives’ Data Collection (MDC) and rates over time were calculated. Preterm birth by Caesarean section before the onset of labour or where labour was induced were considered to be medically indicated.

Main outcome measures: Preterm rates, medically indicated preterm birth rates, mode of delivery and neonatal outcomes, and trends over time.

Results: Among singleton infants, there was no significant change over time in the rate of preterm birth (annual average 5.5%), preterm births that were medically indicated (annual average 29.3%) or neonatal outcomes of preterm births. The rate of indicated preterm birth varied by gestational age and was highest (39.7%) at 29–32 weeks’ gestation. Instrumental preterm births declined over time from 9.5 to 7.8% with a shift from forceps to vacuum use and episiotomy rates declined from 19.7 to 14.8%.

Conclusions: Increases in the reported overall preterm rate (singletons and multiples) were not due to increased delivery of singleton infants. Changes in the management of singleton preterm births were similar to changes observed in term births such as decreasing forceps and episiotomy usage. It may be to time to reassess whether Australian clinicians would be willing to randomise patients to clinical trials of the best method of delivery for preterm infants.
Outpatient management of abnormal smears
Authors: Ward Bruce G , Broe Stephen J
Published: March 2003

Objectives: To review the results of the first 403 women treated at the Abnormal Smear and Colposcopy Unit with special reference to the utility, efficacy, acceptability and economy of in‐office treatment of cervical lesions by large loop or Fischer cone excision.

Design: Retrospective chart review of consecutive patients treated following, referral with an abnormal smear or abnormal cervical morphology, between 1 September 1996 and 1 August 2001.

Setting: Inner city private practice.

Sample: A total of 403 consecutive General Practitioner referred women.

Methods: Details of referral smear result, colposcopically directed biopsy result, subsequent treatment type and histological result including assessability, number of specimens submitted, complications and follow‐up assessment were extracted at chart review. Costs of public hospital inpatient and outpatient care, supplied by the Casemix and Clinical Benchmarking Service, Mater Miseraecordae Public Hospitals (with permission to publish), were compared with Medicare rebates.

Main outcome measures: A total of 187 women were treated by large loop excision of the transformation zone, and 216 by Fischer cone excision. The number of women who were treated as outpatients under local anaesthetic were 395, while eight patients were treated under general anaesthesia as inpatients. There was poor correlation between referring smear, biopsy and subsequent treatment results. Eight patients had abnormal cytology at follow‐up, of whom two have been retreated. Three patients had primary or secondary bleeding requiring treatment and two developed cervical stenosis. Outpatient private practice treatment of women with abnormal smears allows significant savings to the public purse over public or private hospital care.

Conclusions: Outpatient treatment of women with abnormal smears, using the Fischer cone technique, is safe, well accepted, effective and the most cost efficient solution to this public health problem.
Dual effects of arsenic trioxide (As2O3) on non‐acute promyelocytic leukaemia myeloid cell lines: induction of apoptosis and inhibition of proliferation
Authors: Rojewski M. T. , Baldus C. , Knauf W. , Thiel E. , Schrezenmeier H.
Published: March 2003

Summary. Clinical efficacy of As2O3 has been shown in patients with relapsed acute promyelocytic leukaemia (APL). There is evidence that the effects of As2O3 are not restricted to events specific for APL. As2O3 might target mechanisms involved in the pathogenesis of other malignancies. We assessed susceptibility to induction of apoptosis by As2O3 and cytostatics in 22 myeloid and non‐myeloid malignant cell lines. As2O3 was used in concentrations of 0·01–10 µmol/l. Cell lines displayed different kinetics of response and different sensitivity to As2O3. The minimum concentration of As2O3 for induction of apoptosis was 0·1 µmol/l. High concentrations of As2O3 (5 µmol/l) induced apoptosis in a large proportion of cells in all cell lines tested. Low (1 µmol/l As2O3) concentrations induced apoptosis in NB‐4, HL‐60, U‐937, CEM, HL‐60, KG‐1a, PBL‐985, ML‐2 and MV‐4–11, but not in HEL, K‐562, KG‐1 and Jurkat up to 35 d of incubation. However, the non‐apoptotic population of 1 µmol/l As2O3‐treated HEL, K‐562, K‐562 (0·02), K‐562(0·1) and Jurkat showed reduced proliferation. CEM as well as its' multidrug‐resistant derivatives were sensitive to 1 µmol/l As2O3. In summary, these data demonstrate that As2O3‐induced apoptosis is not restricted to cell lines with t(15;17). Apoptosis was induced in vitro by As2O3 concentrations that are achievable in vivo after infusion of well‐tolerated As2O3 doses. Thus, As2O3 might be a suitable therapeutic agent for malignancies other than APL provided the adequate dose and duration of As2O3 treatment are used.
Cytotoxicity of 2‐chlorodeoxyadenosine and arabinosylcytosine in leukaemic lymphoblasts from paediatric patients: significance of cellular nucleoside transporter content
Authors: Wright Adrienne M. P. , Paterson Alan R. P. , Sowa Bernard , Akabutu John J. , Grundy Paul E. , Gati Wendy P.
Published: March 2003

Summary. 2‐chlorodeoxyadenosine (2‐CdA) and arabinosylcytosine (araC) are nucleoside drugs that are used to treat various leukaemias, although 2‐CdA has not been tested extensively in children with acute lymphoblastic leukaemia (ALL). Nucleoside cytotoxicity depends on the conversion of these agents to 5′‐phosphate derivatives, following drug entry into cells via nucleoside transport (NT) processes. This study compared es nucleoside transporter content, determined using a flow cytometric assay with SAENTA [5′‐S‐(2‐aminoethyl)‐N6‐(4‐nitrobenzyl)‐5′‐thioadenosine] fluorescein, and cytotoxicities of 2‐CdA and araC in fresh lymphoblasts from previously untreated paediatric ALL patients and the human T‐lymphoblast cell line, CCRF‐CEM. Lymphoblast samples from individual patients ranged widely in sensitivity to both 2‐CdA (IC50, 6 nmol/l to > 5 μmol/l; mean = 418 nmol/l; n = 8) and araC (IC50, 59 nmol/l to > 5 μmol/l; mean = 1050 nmol/l; n = 7), although IC50 values for the two drugs were correlated (r = 0·78, P = 0·032, n = 7). Cellular es nucleoside transporter content varied more than 35‐fold among samples from 10 patients. The correlation between es nucleoside transporter content and drug sensitivity was statistically significant for araC (r = −0·93, P = 0·023, n = 5), but not for 2‐CdA (r = −0·57, P = 0·23, n = 6). Exposure of CCRF‐CEM cells to araC resulted in a substantial araC concentration‐dependent increase in the relative survival of es transporter‐deficient cells, whereas the increase was slight following exposure to 2‐CdA. We conclude that, in ALL lymphoblasts, es nucleoside transporter content is a determinant of araC sensitivity and that a deficiency in NT may impart resistance to araC.
Prediction of serious complications in patients admitted to a surgical ward
Authors: Veltkamp S C , Kemmeren J M , van der Graaf Y , Edlinger M , van der Werken C
Published: March 2003

Background

Prediction of complications is an essential part of risk management in surgery. Knowing which patients are at high risk of developing complications will contribute to the quality and cost reduction of surgery.

Methods

All patients admitted to a general surgical ward during a 1-year interval were followed until 30 days after discharge. Complications and data on potential risk factors were recorded prospectively. Relative risks were calculated for each risk factor and predictive values for the development of a serious or minor complication were computed using logistic regression analysis. The predictive values of different combinations of variables were expressed as receiver operating characteristic curves.

Results

Of 3075 patients, 375 suffered one or more serious complications and 319 experienced a minor complication. A model was developed for prediction of serious complications, consisting of 11 variables, with an area under the curve (AUC) of 0·79 (95 per cent confidence interval (c.i.) 0·76 to 0·81). The prognostic value of the model for minor complications (seven variables) was lower (AUC 0·68 (95 per cent c.i. 0·65 to 0·71)).

Conclusion

Serious complications in patients admitted to a surgical ward can be predicted using a model consisting of 11 variables. The risk score can be used in the decision-making process before surgery.
Effect ofin vivoadministration of anti-CTLA-4 monoclonal antibody and IL-12 on the induction of low-dose oral tolerance
Authors: BARONE K S , HERMS B , KARLOSKY L , MURRAY S , QUALLS J
Published: March 2003

Oral tolerance has been characterized as an immunological hyporesponsiveness to fed antigen. Previous studies have suggested that high-dose oral tolerance involves the preferential interaction of B7 with CTLA-4 on the T cell. To determine whether similar mechanisms are involved in the induction of low-dose oral tolerance, mice were treated with anti-CTLA-4 monoclonal antibody (MoAb), with or without IL-12, at the time of feeding. Results showed that anti-CTLA-4 MoAb alone failed to restore cellular proliferation, antibody titres and IFN-γ levels; however, IL-4 cytokine levels in OVA-fed mice were partially restored. In contrast, administration of IL-12 along with anti-CTLA-4 MoAb to mice during feeding completely prevented the suppression of Th1 immune responses, as shown by increased serum IgG2a titres, IFN-γ production and cell proliferation. These results suggest that blocking B7-CTLA-4 interactions in the presence of IL-12 prevents the induction of low-dose oral tolerance at the Th1 cell level.
Metabolic characterization of sciadonic acid (5c,11c,14c‐eicosatrienoic acid) as an effective substitute for arachidonate of phosphatidylinositol
Authors: Tanaka Tamotsu , Morishige Jun‐ichi , Takimoto Tatsunori , Takai Yoshimichi , Satouchi Kiyoshi
Published: March 2003

Sciadonic acid (20:3 Δ‐5,11,14) is an n‐6 series trienoic acid that lacks the Δ8 double bond of arachidonic acid. This fatty acid is not converted to arachidonic acid in higher animals. In this study, we characterized the metabolic behavior of sciadonic acid in the process of acylation to phospholipid of HepG2 cells. One of the characteristics of fatty acid compositions of phospholipids in sciadonic acid‐supplemented cells is a higher proportion of sciadonic acid in phosphatidylinositol (PtdIns) (27.4%) than in phosphatidylethanolamine (PtdEtn) (23.2%), phosphatidylcholine (PtdCho) (17.3%) and phosphatidylserine (PtdSer) (20.1%). Similarly, the proportion of arachidonic acid was higher in PtdIns (35.8%) than in PtdEtn (29.1%), PtdSer (18.2%) and PtdCho (20.2%) in arachidonic‐acid‐supplemented cells. The extensive accumulation of sciadonic acid in PtdIns resulted in the enrichment of newly formed 1‐stearoyl‐2‐sciadonoyl molecular species (38%) in PtdIns and caused the reduction in the level of pre‐existing arachidonic‐acid‐containing molecular species. The kinetics of incorporation of sciadonic acid to PtdEtn, PtdSer and PtdIns of cells were similar to those of arachidonic acid. In contrast to sciadonic acid, neither eicosapentaenoic acid (20:5 Δ‐5,8,11,14,17) nor juniperonic acid (20:4 Δ‐5,11,14,17) accumulated in the PtdIns fraction. Rather, these n‐3 series polyunsaturated fatty acids, once incorporated into PtdIns, tended to be excluded from PtdIns. In addition, the level of arachidonic‐acid‐containing PtdIns molecular species remained unchanged by eicosapentaenoic‐acid‐supplementation. These results suggest that sciadonic acid or sciadonic‐acid‐containing glycerides are metabolized in a similar manner to arachidonic acid or arachidonic‐acid‐containing glyceride in the biosynthesis of PtdIns and that sciadonic acid can effectively modify the molecular species composition of PtdIns in HepG2 cells. In this regard, sciadonic acid will be an interesting experimental tool to clarify the significance of arachidonic acid‐residue of PtdIns‐origin bioactive lipids.
Application of radiolabeled tracers to biocatalytic flux analysis
Authors: Yanagimachi Kurt S. , Stafford Daniel E. , Dexter Annette F. , Sinskey Anthony J. , Drew Stephen , Stephanopoulos Gregory
Published: March 2003

Radiolabeled tracers can provide valuable information about the structure of and flux distributions in biocatalytic reaction networks. This method derives from prior studies of glucose metabolism in mammalian systems and is implemented by pulsing a culture with a radiolabeled metabolite that can be transported into the cells and subsequently measuring the radioactivity of all network metabolites following separation by liquid chromatography. Intracellular fluxes can be directly determined from the transient radioactivity count data by tracking the depletion of the radiolabeled metabolite and/or the accompanying accumulation of any products formed. This technique differs from previous methods in that it is applied within a systems approach to the problem of flux determination. It has been used for the investigation of the indene bioconversion network expressed in Rhodococcus sp. KY1. Flux estimates obtained by radioactive tracers were confirmed by macroscopic metabolite balancing and showed that indene oxidation in steady state chemostat cultures proceeds primarily through a monooxygenase activity forming (1S,2R)‐indan oxide, with no dehydrogenation of trans‐(1R,2R)‐indandiol. These results confirmed the significance of indan oxide formation and identified the hydrolysis of indan oxide as a key step in maximizing the production of (2R)‐indandiol, a chiral precursor of the HIV protease inhibitor, Crixivan®.
Heterologous expression and characterization of the exopolysaccharide from Streptococcus thermophilus Sfi39
Authors: Germond Jacques‐Edouard , Delley Michèle , D'Amico Nicola , Vincent Sébastien J. F.
Published: March 2003

The genes responsible for exopolysaccharide (EPS) synthesis in Streptococcus thermophilus Sfi39 were identified on a 20‐kb genomic fragment. The two genes, epsE and epsG, were shown to be involved in EPS synthesis as their disruption lead to the loss of the ropy phenotype. Several naturally selected nonropy mutants were isolated, one acquired an insertion sequence (IS)‐element (IS905) in the middle of the eps gene cluster. The eps gene cluster was cloned and transferred into a nonEPS‐producing heterologous host, Lactococcus lactis MG1363. The EPS produced was shown by chemical analysis and NMR spectroscopy to be identical to the EPS produced by S. thermophilus Sfi39. This demonstrated first that all genes needed for EPS production and export were present in the S. thermophilus Sfi39 eps gene cluster, and second that the heterologous production of an EPS was possible by transfer of the complete eps gene cluster alone, provided that the heterologous host possessed all necessary genetic information for precursor synthesis.
Homocysteine‐induced decrease in endothelin‐1 production is initiated at the extracellular level and involves oxidative products
Authors: Drunat Séverine , Moatti Nicole , Paul Jean Louis , Cogny Anne , Benoit Marie‐Odile , Demuth Karine
Published: March 2003

The increased cardiovascular risk associated with hyperhomocysteinemia has been partly related to homocysteine (Hcy)‐induced endothelial cell dysfunction. However, the intra or extracellular starting point of the interaction between Hcy and endothelial cells, leading to cellular dysfunction, has not yet been identified. We investigated the effects of both intracellular and extracellular Hcy accumulation on endothelin‐1 (ET‐1) synthesis by cultured human endothelial cells. Incubation of cultures with methionine (1.0 mmol·L−1) for 2 h induced a slight increase in cellular Hcy content but no change in ET‐1 production. Incubation of cells with Hcy (0.2 mmol·L−1) led to a significant fall in ET‐1 generation, accompanied by a significant increase in cellular Hcy content. Addition of the amino‐acid transport system L substrate 2‐amino‐2‐norbornane carboxylic acid had no effect on the Hcy‐induced decrease in ET‐1 production but significantly inhibited the Hcy‐induced increase in the cellular Hcy content. Incubation of cells with a lower Hcy concentration (0.05 mmol·L−1) also reduced ET‐1 production without increasing the cellular Hcy content. Co‐incubation with extracellular free‐radical inhibitors (superoxide dismutase, catalase and mannitol) markedly reduced the effect of Hcy on ET‐1 production. Thus, it is extracellular Hcy accumulation that triggers the decrease in ET‐1 production by endothelial cells through oxidative products.
Engineering of the protein environment around the redox‐active TyrZ in photosystem II
Authors: Wiklund Ronney , Salih Gaza Farag , Mäenpää Pirkko , Jansson Christer
Published: March 2003

The photosystem II reaction centre protein D1 is encoded by the psbA gene. By activation of the silent and divergent psbA1 gene in the cyanobacterium Synechocystis 6803, a novel D1 protein, D1′, was produced [Salih, G. & Jansson, C. (1997) Plant Cell9, 869–878]. The D1′ protein was found to be fully operational although it deviates from the normal D1 protein in 54 out of 360 amino acids. Two notable amino‐acid substitutions in D1′ are the replacements of F186 by a leucine and P162 by a serine. The F186 and P162 positions are located in the vicinity of the reaction centre chlorophyll dimer P680 and the redox‐active Y161 (TyrZ), and F186 has been implicated in the electron transfer between Y161 and P680. The importance of F186 was addressed by construction of engineered D1 proteins in Synechocystis 6803. F186 was replaced by leucine, serine, alanine, tyrosine or tryptophan. Only the leucine replacement yielded a functional D1 protein. Other substitutions did not support photoautotrophic growth and the corresponding mutants showed no or very poor oxygen evolving activity. In the F186Y and F186W mutants, the D1 protein failed to accumulate to appreciable levels in the thylakoid membrane. The F186S mutation severely increased the light sensitivity of the D1 protein, as indicated by the presence of a 16‐kDa proteolytic degradation product. We conclude that the hydrophobicity and van der Waals volume are the most important features of the residue at position 186. Exchanging P162 for a serine yielded no observable phenotype.
Transcriptional regulation of the ovine intestinal Na+/glucose cotransporter SGLT1 gene
Authors: Vayro Steven , Wood I. Stuart , Dyer Jane , Shirazi‐Beechey Soraya P.
Published: March 2003

Dietary sugars d‐glucose and d‐galactose are transported across the intestinal brush‐border membrane by the Na+/glucose cotransporter, SGLT1. In various species studied, it has been shown that the activity, and expression, of intestinal SGLT1 is regulated by dietary sugars. We report in this paper that regulation of the intestinal SGLT1 gene by lumenal sugar is due, in part, to an increase in transcription. Using deletion analyses of the −66/+21‐bp fragment, we have identified the minimal region of the ovine SGLT1 promoter able to support transcription. Site‐directed mutagenesis of the hepatic nuclear factor‐1 (HNF‐1) consensus motif within this domain eliminates basal promoter function. In addition, we show direct evidence for glucose‐induced activation of the −66/+21‐bp promoter region. There is a co‐ordinated decline in the abundance of ovine intestinal HNF‐1 and SGLT1 transcripts during transition from preruminant to adult ruminant. This decline is recovered after glucose infusion of adult sheep intestine. Similarly, as shown using DNA mobility‐shift assays, the intensity of the HNF‐1‐binding complex to the target promoter sequence decreases during maturation of the animal; this is restored after intestinal sugar infusion. These data indicate that HNF‐1 plays an important role in the glucose responsiveness of the ovine SGLT1 gene. This is the first report of in vitro glucose‐induced activation of the intestinal SGLT1 promoter and identification of a glucose‐responsive region of the ovine SGLT1 promoter.
Covariance of tricarboxylate carrier activity and lipogenesis in liver of polyunsaturated fatty acid (n‐6) fed rats
Authors: Zara Vincenzo , Giudetti Anna Maria , Siculella Luisa , Palmieri Ferdinando , Gnoni Gabriele V.
Published: March 2003

The mitochondrial tricarboxylate (citrate) carrier plays an important role in hepatic intermediary metabolism because, among other functions, it supplies the cytosol with acetyl units for fatty‐acid synthesis. In this study, the effect of polyunsaturated fatty acids (PUFA, n‐6) on the function of this mitochondrial transporter and on lipogenic enzyme activities was investigated by feeding rats for 4 weeks with a 15%‐fat diet composed of high linoleic safflower oil. Citrate transport was strongly reduced in liver mitochondria isolated from PUFA‐treated rats. A reduced transport activity was also observed when solubilized mitochondrial citrate carrier from PUFA‐treated rats was reconstituted into liposomes. In the same animals, a decrease of cytosolic lipogenic enzyme activities was observed. These results indicate a coordinated modulation of citrate carrier and of lipogenic enzyme activities by PUFA feeding. Kinetic analysis of the carrier activity showed that only Vmax decreased, whereas Km was almost virtually unaffected. The PUFA‐mediated effect is most likely due to the reduced mRNA level and lower content of the citrate carrier protein observed in the safflower oil‐fed rats.
Evidence of a functional requirement for a carbamoylated lysine residue in MurD, MurE and MurF synthetases as established by chemical rescue experiments
Authors: Dementin Sébastien , Bouhss Ahmed , Auger Geneviève , Parquet Claudine , Mengin‐Lecreulx Dominique , Dideberg Otto , van Heijenoort Jean , Blanot Didier
Published: March 2003

Enzymes MurD, MurE, MurF, folylpolyglutamate synthetase and cyanophycin synthetase, which belong to the Mur synthetase superfamily, possess an invariant lysine residue (K198 in the Escherichia coli MurD numbering). Crystallographic analysis of MurD and MurE has recently shown that this residue is present as a carbamate derivative, a modification presumably essential for Mg2+ binding and acyl phosphate formation. In the present work, the importance of the carbamoylated residue was investigated in MurD, MurE and MurF by site‐directed mutagenesis and chemical rescue experiments. Mutant proteins MurD K198A/F, MurE K224A and MurF K202A, which displayed low enzymatic activity, were rescued by incubation with short‐chain carboxylic acids, but not amines. The best rescuing agent was acetate for MurD K198A, formate for K198F, and propionate for MurE K224A and MurF K202A. In the last of these, wild‐type levels of activity were recovered. A complementarity between the volume of the residue replacing lysine and the length of the carbon chain of the acid was noted. These observations support a functional role for the carbamate in the three Mur synthetases. Experiments aimed at recovering an active enzyme by introducing an acidic residue in place of the invariant lysine residue were also undertaken. Mutant protein MurD K198E was weakly active and was rescued by formate, indicating the necessity of correct positioning of the acidic function with respect to the peptide backbone. Attempts at covalent rescue of mutant protein MurD K198C failed because of its lack of reactivity towards haloacids.