bluuebunny/crossref_metadata_2025_split huggingface dataset:
Transcriptional Targeting of Lentiviral Vectors by Long Terminal Repeat Enhancer Replacement
Authors: Lotti Francesco , Menguzzato Emilio , Rossi Claudia , Naldini Luigi , Ailles Laurie , Mavilio Fulvio , Ferrari Giuliana 
Published: July 2002

ABSTRACT

Gene therapy of many genetic diseases requires permanent gene transfer into self-renewing stem cells and restriction of transgene expression to specific progenies. Human immunodeficiency virus (HIV)-derived lentiviral vectors are very effective in transducing rare, nondividing stem cell populations (e.g., hematopoietic stem cells) without altering their long-term repopulation and differentiation capacities. We developed a strategy for transcriptional targeting of lentiviral vectors based on replacing the viral long terminal repeat (LTR) enhancer with cell lineage-specific, genomic control elements. An upstream enhancer (HS2) of the erythroid-specific GATA-1 gene was used to replace most of the U3 region of the LTR, immediately upstream of the HIV type 1 (HIV-1) promoter. The modified LTR was used to drive the expression of a reporter gene (the green fluorescent protein [GFP] gene), while a second gene (a truncated form of the p75 nerve growth factor receptor [ΔLNGFR]) was placed under the control of an internal constitutive promoter to monitor cell transduction, or to immunoselect transduced cells, independently from the expression of the targeted promoter. The transcriptionally targeted vectors were used to transduce cell lines, human CD34
+
hematopoietic stem-progenitor cells, and murine bone marrow (BM)-repopulating stem cells. Gene expression was analyzed in the stem cell progeny in vitro and in vivo after xenotransplantation into nonobese diabetic-SCID mice or BM transplantation in coisogenic mice. The modified LTR directed high levels of transgene expression specifically in mature erythroblasts, in a TAT-independent fashion and with no alteration in titer, infectivity, and genomic stability of the lentiviral vector. Expression from the modified LTR was higher, better restricted, and showed less position-effect variegation than that obtained by the same combination of enhancer-promoter elements placed in a conventional, internal position. Cloning of the woodchuck hepatitis virus posttranscriptional regulatory element at a defined position in the targeted vector allowed selective accumulation of the genomic transcripts with respect to the internal RNA transcript, with no loss of cell-type restriction. A critical advantage of this targeting strategy is the use of a spliced, major viral transcript to express a therapeutic gene and that of an internal, independently regulated promoter to express an additional gene for either cell marking or in vivo selection purposes.
Preconcentration and Separation of Gold on Modified Silica Gel
Authors: Hájková Jana , Kanický Viktor , Otruba Vítězslav 
Published: July 2002

Selective preconcentration of gold in the form of ion associates of Au(III) chloro complex or Au(I) cyano complex with quaternary bases was studied using modified silica gel. Solutions containing gold in the presence of the complexing anion and a quaternary base were pumped through a Separon™ SGX C18 column. After elution with 96 vol.% ethanol, the eluate was evaporated in the presence a complexing agent (chloride or cyanide). The resulting aqueous solutions were analyzed with inductively coupled plasma atomic emission spectrometry. The influence of concentration of onium salts, chlorides, nitrates, and the influence of the sample volume on the sorption were studied. The sorption flow rate and the elution volume were optimized, and the separation from a geological sample matrix was verified. The best recovery (100%) of preconcentration of Au(III) chloro complex was obtained with [1-(ethoxycarbonyl)pentadecyl]trimethylammonium bromide and 1-hexadecylpyridinium chloride at concentrations of 0.006 and 0.004 mol dm-3, respectively. The sorption flow rate of a sample may vary in the range 0.4-7 cm3 min-1, the elution volume was between 5 and 6 cm3. The recovery decreased with increasing sample volume above 250 cm3 and was diminished by 10% in the presence of nitrates above 0.4 mol dm-3. Major accompanying elements Fe and Mn, which considerably interfere at the Au I 242.795 nm line, were quantitatively separated from gold. A Czech certified reference material 1001 Mokrsko was analyzed using the developed preconcentration technique and inductively coupled plasma atomic emission spectrometry, inductively coupled plasma mass spectrometry, and atomic absorption spectrometry. Sorption of ion associates of Au(I) cyano complex was also efficient.
Characterisation of breathing and associated central autonomic dysfunction in the Rett disorder
Authors: Julu P O O , Kerr A M , Apartopoulos F , Al-Rawas S , Engerström I Witt , Engerström L , Jamal G A , Hansen S 
Published: July 2002

AIMTo investigate breathing rhythm and brain stem autonomic control in patients with Rett disorder.SETTINGTwo university teaching hospitals in the United Kingdom and the Rett Centre, Sweden.PATIENTS56 female patients with Rett disorder, aged 2–35 years; 11 controls aged 5–28 years.DESIGNOne hour recordings of breathing movement, blood pressure, ECG R-R interval, heart rate, transcutaneous blood gases, cardiac vagal tone, and cardiac sensitivity to baroreflex measured on-line with synchronous EEG and video. Breathing rhythms were analysed in 47 cases.RESULTSRespiratory rhythm was normal during sleep and abnormal in the waking state. Forced and apneustic breathing were prominent among 5–10 year olds, and Valsalva breathing in the over 18 year olds, who were also most likely to breathe normally. Inadequate breathing peaked among 10–18 year olds. Inadequate and exaggerated breathing was associated with vacant spells. Resting cardiac vagal tone and cardiac sensitivity to baroreflex were reduced.CONCLUSIONSLabile respiratory rhythms and poor integrative inhibition in Rett disorder suggest brain immaturity. Linking this to an early monoaminergic defect suggests possible targets for the MECP2 gene in clinical intervention. Exaggerated and inadequate autonomic responses may contribute to sudden death.
Short term power output in relation to growth and maturation
Authors: Armstrong N , Welsman J R , Chia M Y H 
Published: July 2002

Objective—To examine short term power output during growth and maturation using a multilevel modelling approach.Methods—Body mass, stature, and triceps and subscapular skinfold thicknesses of boys and girls, aged 12.2 (0.4) years (mean (SD)) at the onset of the study, were measured at age 12, 13, and 17 years. Sexual maturation, classified according to Tanner's stage of pubic hair development, was assessed on the first two occasions and assumed to be stage 5 at 17 years. Peak power (PP) and mean power (MP) were assessed on each occasion using the Wingate anaerobic test.Results—Initial models, founded on 417 determinations of short term power output, identified body mass, stature, and age as significant explanatory variables of both PP and MP. The values for girls were significantly lower than those for boys, and a significant age by sex interaction described a progressive divergence in the MP of boys and girls. The introduction of sum of two skinfold thicknesses produced a model with an improvement in fit as indicated by a significant change in log likelihood. The stature term was negated and the body mass term increased. The age and sex terms were reduced but remained significant. The age by sex interaction term remained a significant explanatory variable for MP. Maturity effects were non-significant additional explanatory variables in all models of power output.Conclusion—The values of PP and MP for boys are higher than those for girls, and, for MP, sex differences increase with age. Body mass and skinfold thicknesses are significant influences on both PP and MP, but age exerts a positive but non-linear effect on power output independent of body size and fatness.
Effect of warming up on knee proprioception before sporting activity
Authors: Bartlett M J , Warren P J 
Published: July 2002

Background: It is now generally accepted that the ligamentous structures of the knee not only act as mechanical restraints but also have a neurophysiological role in joint function and protection. A report that knee joint laxity increases with exercise raised the question as to whether there is any compensatory change in joint position appreciation.Objective: To test whether there is a compensatory mechanism for increased ligamentous laxity during normal levels of activity.Methods: Joint position appreciation was measured, using a previously reported technique, in the knees of sportsmen at rest and after warm up.Results: Joint position appreciation was found to be significantly more sensitive after warm up (p = 0.005).Conclusions: These findings indicate that joint position appreciation within the knee accommodates physiological changes within the ligaments and muscles after exercise.
Effects of exercise on soluble transferrin receptor and other variables of the iron status
Authors: Schumacher Y O , Schmid A , König D , Berg A 
Published: July 2002

Background:Soluble transferrin receptor (sTfr) is a new marker of iron status and erythropoietic activity. It has been included in multivariable blood testing models for the detection of performance enhancing erythropoietin misuse in sport.Objective:To evaluate the effect of different types and volumes of physical activity on sTfr concentration, variables of iron status (ferritin, transferrin, iron, and protein), and haematological indices.Methods:Thirty nine subjects were divided into three groups: 1, untrained (n = 12); 2, moderately trained (n = 14); 3, highly trained (n = 13, seven men, six women). Groups 1 and 2 carried out two exercise tests: an incremental running test until exhaustion (test A) and a 45 minute constant speed running test at 70% Vo2max(test B). Group 3 performed three days (women) or four days (men) of prolonged aerobic cycling exercise. The above variables together with haemoglobin and packed cell volume were analysed in venous blood samples before and after exercise. Changes in blood and plasma volume were estimated.Results:sTfr levels were slightly increased in trained and untrained subjects immediately after test A. Test B and aerobic exercise had no significant effect on sTfr. Ferritin levels were increased after the laboratory tests for trained and untrained subjects and after prolonged aerobic exercise in male cyclists. Transferrin was increased significantly in trained and untrained subjects after both laboratory tests, but remained unchanged after prolonged exercise. Plasma and blood volumes were decreased after the laboratory tests but increased after aerobic exercise. No differences in the variables were observed between trained and untrained subjects with respect to response to exercise.Conclusion:The changes in sTfr and the variables of iron status can be mainly attributed to exercise induced changes in volume. Taking these limitations into account, sTfr can be recommended as a marker of iron deficiency in athletes.
Ignorance is bliss? HIV and moral duties and legal duties to forewarn
Authors: Bennett Rebecca , Draper Heather , Frith Lucy 
Published: July 2002

In 1997, a court in Cyprus jailed Pavlos Georgiou for fifteen months for knowingly infecting a British woman, Janet Pink, with HIV-1 through unprotected sexual intercourse. Pink met Georgiou in January 1994 whilst on holiday. She discovered that she had contracted the virus from him in October 1994 but continued the relationship until July 1996 when she developed AIDS. She returned to the UK for treatment and reported Georgiou to the Cypriot authorities.1There have been a number of legal cases involving deliberate transmission of HIV, but most have involved forced exposure to infected bodily fluids for example, rape or biting, and have been dealt with using the existing legislation for rape or assault. While it is often difficult to prove responsibility for transmission in cases of forced exposure to HIV, it is even more contentious in cases like those of Janet Pink where an individual has consented to sex but claims that he/she was not forewarned of his/herpartner's HIV-positive status. At present there is no specific criminal offence of having unprotected sexual intercourse without disclosing one's HIV-positive status but a prosecution could possibly be brought under any one of a number of existing offences.2Perhaps a change of policy needs to be considered. The Home Office has issued a consultation document which outlines a proposal that will allow the criminalisation of intentional transmission of diseases, like HIV, that are likely to cause serious harm. This revised legislation would cover all other potentially fatal diseases (including salmonella and legionnaire's disease, for instance) but seems primarily to be targeted at HIV transmission. Should transmission of HIV through consensual sex, without the HIV-positive status of the individual being disclosed, be an offence? This question, and that of whether there is a moral obligation to disclose a positive HIV status prior to having a sexual relationship is the subject of this paper.
Short term exposure to airborne microbial agents during farm work: exposure-response relations with eye and respiratory symptoms
Authors: Eduard W , Douwes J , Mehl R , Heederik D , Melbostad E 
Published: July 2002

OBJECTIVESExposure to high levels of non-infectious microbial agents is recognised as a cause of respiratory disease in working populations, but except for endotoxins, little is known about exposure-response relations. As these effects do not depend on viability, exposure to non-viable microbial agents is important. Various methods not based on microbial cultures were explored to study the complex microbial exposure of farmers and associations with acute symptoms during work.METHODSAirborne exposure was measured when farmers carried out specific tasks. Fungal spores, bacteria, endotoxins, β(1→3)-glucans, fungal antigens specific forPenicilliumandAspergillusspecies, and mites were measured by methods not based on microbial cultures. Also silica, inorganic and organic dust, ammonia, hydrogen sulphide, and nitrogen dioxide were measured. Respiratory, and nose and eye symptoms experienced during measurements were recorded by a short questionnaire. Both univariate and multivariate statistical analyses were applied to assess the relations between exposure and acute symptoms.RESULTS106 Farmers and their spouses participated in this study. Prevalences of work related symptoms were: wheezing 3%; chest tightness 7%; cough 14%; eye symptoms 18%; and nose symptoms 22%. Prevalence ratios for nose and eye symptoms were 4–8 after exposure to 20–500×103fungal spores/m3and higher, and a prevalence ratio for cough was 4 after exposure to 500–17 000×103fungal spores/m3. Nose symptoms were also associated with exposure to silica with prevalence ratios of 4–6 after exposure to 0.015–0.075 mg /m3and higher.CONCLUSIONSFarmers had a high occurrence of symptoms of the nose and eyes as well as cough during work. These symptoms were associated in a dose dependent manner with exposure to fungal spores. Nose symptoms were also associated with exposure to silica.
Sickness absence in hospital physicians: 2 year follow up study on determinants
Authors: Kivimäki M , Sutinen R , Elovainio M , Vahtera J , Räsänen K , Töyry S , Ferrie J E , Firth-Cozens J 
Published: July 2002

OBJECTIVESTo identify determinants of sickness absence in hospital physicians.METHODSThe Poisson regression analyses of short (1–3 days) and long (>3 days) recorded spells of sickness absence relating to potential determinants of sickness absence were based on a 2 year follow up period and cohorts of 447 (251 male and 196 female) physicians and 466 controls (female head nurses and ward sisters).RESULTSThere were no differences in health outcomes, self rated health status, prevalence of chronic illness, and being a case on the general health questionnaire (GHQ), between the groups but physicians took one third to a half the sick leave of controls. All the health outcomes were strongly associated with sickness absence in both groups. Of work related factors, teamwork had the greatest effect on sickness absence in physicians but not in the controls. Physicians working in poorly functioning teams were at 1.8 (95% confidence interval (95% CI) 1.3 to 3.0) times greater risk of taking long spells than physicians working in well functioning teams. Risks related to overload, heavy on call responsibility, poor job control, social circumstances outside the workplace, and health behaviours were smaller.CONCLUSIONThis is the first study of hospital physicians to show the association between recorded sickness absence and factors across various areas of life. In this occupational group, sickness absence is strongly associated with health problems, and the threshold for taking sick leave is high. Poor teamwork seems to contribute to the sickness absenteeism of hospital physicians even more than traditional psychosocial risks—such as overload and low job control. These findings may have implications for training and health promotion in hospitals.
Effects on the nervous system in different groups of workers exposed to aluminium
Authors: Iregren A , Sjögren B , Gustafsson K , Hagman M , Nylén L , Frech W , Andersson M , Ljunggren K G , Wennberg A 
Published: July 2002

OBJECTIVETo investigate possible neurotoxic effects in groups of aluminium pot room and foundry workers, aluminium welders, and a small group of workers exposed to aluminium in the production of flake powder.METHODSExposure to aluminium was evaluated with aluminium concentrations in blood and urine as well as a questionnaire. The groups exposed to aluminium were compared with a group of mild steel welders. Neurotoxic effects were studied with mood and symptom questionnaires and several psychological and neurophysiological tests.RESULTSThe pot room and foundry workers showed very low aluminium uptake as their aluminium concentrations in blood and urine were close to normal, and no effects on the nervous system were detected. The group of workers exposed to flake powder had high concentrations of aluminium in blood and urine, even higher than those of the aluminium welders. However, aluminium could not be shown to affect the functioning of the nervous system in flake powder producers. Although significant effects could not be shown in the present analysis of the data on welders, the performance of the welders exposed to high concentrations of aluminium was affected according to the analyses in the original paper from this group.CONCLUSIONSFor the pot room and foundry workers no effects related to the exposure to aluminium could be found. For the group of flake powder producers exposed for a short term no effects on the nervous systems were evident despite high levels of exposure. Due to the high concentrations of aluminium in the biological samples of this group, measures to reduce the exposure to aluminium are recommended, as effects on the central nervous system might develop after protracted exposures. However, this assumption needs to be verified in further studies.
Upper airway inflammation and respiratory symptoms in domestic waste collectors
Authors: Wouters I M , Hilhorst S K M , Kleppe P , Doekes G , Douwes J , Peretz C , Heederik D 
Published: July 2002

Objectives: To compare respiratory symptoms and upper airway inflammation in domestic waste collectors and controls, and to find the association between measures of upper airway inflammation on the one hand and exposure concentrations of organic dust or respiratory symptoms on the other hand.Methods: In a cross sectional study among 47 waste collectors and 15 controls, questionnaire data on respiratory symptoms were collected. Nasal lavage (NAL), to assess upper airway inflammation, was performed before and after a work shift at the beginning and at the end of the working week. In NAL fluid, cells were counted and differentiated and concentrations of interleukin 6 (IL6), IL8, tumour necrosis factor-α (TNFα), and IL1β were measured. In collectors, inhalable dust samples were collected in which bacterial endotoxin and mould β(1→3)-glucan were assessed.Results: Prevalence of respiratory symptoms was higher in waste collectors than in controls. Geometric mean exposure concentrations were 0.58 mg/m3for dust, 39 EU/m3for endotoxin, and 1.3 μg/m3for β(1→3)-glucan. At the end of the week collectors had higher concentrations of total cells and IL8 in NAL before and after a shift than controls (cells, before 1.9-fold p<0.10, after 3.3-fold p<0.01; IL8, before and after 1.8-fold p<0.05), and after/before work shift ratios of total cells were also higher (2.3-fold p=0.06) in collectors than in controls. Cells in NAL fluid consisted predominantly of neutrophils and epithelial cells, whereas eosinophils and mononuclear cells were rarely found. Exposure to dust and endotoxin was associated with concentrations of IL8 after the shift (p<0.05). Increased concentrations of IL8 (p<0.05) and total cells (p<0.10) after the shift were associated with respiratory symptoms. Concentrations of IL6, TNFα, and IL1β were not associated with waste collecting, symptoms, or exposure.Conclusions: Waste collectors show signs of increased upper airway inflammation and respiratory symptoms compared with controls. Exposure to organic dust probably underlies the inflammation mediated by neutrophils that result in respiratory symptoms.
Suicide mortality among electricians in the Swedish construction industry: Table 1
Authors: Järvholm B , Stenberg A 
Published: July 2002

Objectives: To investigate the risk of suicide in Swedish electricians employed in the construction industry. A few studies have indicated an increased risk of suicide for electricians in the construction industry and electricians exposed to electromagnetic fields.Methods: This is a cohort study. Electricians were identified through a computerised register of construction workers who had participated in health examinations in 1971–92. In this register, 33 719 male electricians were identified together with a reference group consisting of 72 653 male glass or woodworkers. Through a linkage with the Swedish Death Register, the cause of death was identified to the end of 1997. Mortality as a result of suicide was also compared with the general population with adjustments for sex, age, and period.Results: The risk of mortality from suicide was decreased for electricians (standardised mortality ratio (SMR) 0.58, 95% confidence interval (95% CI) 0.47 to 0.71) and for the reference group of construction workers (SMR 0.81, 95% CI 0.72 to 0.91) compared with the general population.Conclusion: Contrary to some other studies, risk of suicide was not increased among electricians in the construction industry.