bluuebunny/crossref_metadata_2025_split huggingface dataset:
Helicobacter pylori infection induced alteration of gene expression in human gastric cells
Authors: Chiou C-C , Chan C-C , Sheu D-L , Chen K-T , Li Y-S , Chan E-C 
Published: July 2002

BACKGROUNDHelicobacter pylori, a human pathogen responsible for many digestive disorders, induces complex changes in patterns of gene expression in infected tissues. cDNA expression arrays provide a useful tool for studying these complex phenomena.AIMTo identify genes that showed altered expression after H pylori infection of human gastric cells compared with uninfected controls.METHODSThe gastric adenocarcinoma cell line AGS was cocultivated withH pylori. Growth of infected cells was determined by trypan blue exclusion assay. Complementary DNA probes derived from H pylori treated and untreated cells were hybridised to two identical Atlas human cDNA expression arrays, and those genes with altered expression levels were identified. A real time quantitative reverse transcription-polymerase chain reaction assay was used to better define expression patterns of these genes in endoscopically gastric mucosal biopsies with and withoutH pylori infection.RESULTSOver 24 hours, coincubation with H pylori inhibited AGS cell growth but did not cause a noticeable degree of cell death.H pylori treatment altered the pattern of gene expression in AGS cells. We identified 21 overexpressed genes and 17 suppressed genes from the cDNA expression arrays. The majority of genes were transcription factors such asc-jun, BTEB2, andETR101. Other genes were involved in signal transduction pathways, such as MAP kinase, interleukin 5, and insulin-like growth factor. Genes involved in cell cycle regulation and differentiation, such as CDC25B andNM23-H2, were also identified. In patients with H pylori infection (n=20), there was a significant difference forERCC3, Id-2, andNM23-H2 mRNA levels in infected gastric mucosa compared with uninfected gastric mucosa in patients without peptic diseases (n=20) (ERCC3 4.75 molecules/104 β-actin mRNA moleculesv 13.65, p<0.001;Id-2 16.1 v 23.4, p<0.05; NM23-H2 17.5v 45.5, p<0.001). There was no significant difference between mRNA levels of c-jun andCDC25B in H pylori colonised gastric mucosa and uninfected mucosa.CONCLUSIONWe demonstrated that H pylori infection caused alteration of gene expression in AGS cells. The differential hybridisation technique of Atlas human cDNA expression array is a useful method to identify host genes involved in pathogenic mechanisms in H pylori infection.
Wilson's disease with severe hepatic insufficiency: beneficial effects of early administration of D-penicillamine
Authors: Durand F , Bernuau J , Giostra E , Mentha G , Shouval D , Degott C , Benhamou J P , Valla D 
Published: July 2002

BACKGROUNDWilson's disease, heralded by severe hepatic insufficiency, is a rare disorder for which emergency liver transplantation is considered to be the only effective therapy.AIMSTo report the features of Wilson's disease with severe hepatic insufficiency in a series of 17 patients and, during the second period of the study, to assess the efficacy of a policy consisting of early administration of D-penicillamine.PATIENTSSeventeen consecutive patients with Wilson's disease were studied. During the first period of the study (up to 1979), none of the patients received D-penicillamine. During the second period (after 1979), all patients without encephalopathy at admission received D-penicillamine.RESULTSThe four patients observed during the first period who did not have encephalopathy at admission and did not receive D-penicillamine progressed to encephalopathy and died. Among the 13 consecutive patients observed during the second period, two patients with encephalopathy at admission did not receive D-penicillamine and were transplanted. The 11 remaining patients all received D-penicillamine. Ten of these patients survived without the need for transplantation and returned to compensated liver disease without liver insufficiency. In one patient, liver insufficiency progressed and transplantation had to be performed.CONCLUSIONSIn most patients with Wilson's disease heralded by severe hepatic insufficiency and without encephalopathy at admission, early administration of D-penicillamine was associated with survival without transplantation. These results suggest the importance of early diagnosis of this form of Wilson's disease before the onset of encephalopathy, and favour early administration of D-penicillamine which could avoid the need for transplantation in most cases.
Benign monoclonal expansion of CD8+ lymphocytes in HIV infection
Authors: Smith Penelope R , Cavenagh Jamie D , Milne Tim , Howe Denise , Wilkes Susanna J , Sinnott Paul , Forster Greta E , Helbert Matthew 
Published: July 2002

Background—A transient expansion of the CD8+ T cell pool normally occurs in the early phase of HIV infection. Persistent expansion of this pool is observed in two related settings: diffuse infiltrative lymphocytosis syndrome (DILS) and HIV associated CD8+ lymphocytosis syndrome.Aim—To investigate a group of HIV infected patients with CD8+ lymphocytosis syndrome with particular emphasis on whether monoclonality was present.Methods—A group of 18 patients with HIV-1 infection and persistent circulating CD8+ lymphocytosis was compared with 21 HIV positive controls. Serum samples were tested for antinuclear antibodies, antibodies to extractable nuclear antigens, immunoglobulin levels, paraproteins, human T lymphotropic virus type 1 (HTLV-1), Epstein-Barr virus, and cytomegalovirus serology. Lymphocyte phenotyping and HLA-DR typing was performed, and T cell receptor (TCR) gene rearrangement studies used to identify monoclonal populations of T cells. CD4+ and CD8+ subsets of peripheral blood lymphocytes were purified to determine whether CD8+ populations inhibited HIV replication in autologous CD4+ cells.Results—A subgroup of patients with HIV-1 infection was found to have expanded populations of CD8+ T cell large granular lymphocytes persisting for 6 to 30 months. The consensus immunophenotype was CD4− CD8+ DRhighCD11a+ CD11c+ CD16− CD28± CD56− CD57+, consistent with typical T cell large granular lymphocytes expressing cellular activation markers. Despite the finding of monoclonal TCR gene usage in five of 18 patients, there is evidence that the CD8+ expansions are reactive populations capable of mediating non-cytotoxic inhibition of HIV replication.Conclusions—A subgroup of HIV positive patients has CD8+ lymphocytosis, but despite the frequent occurrence of monoclonal TCR gene usage there is evidence that this represents an immune response to viral infection rather than a malignant disorder.
Estimating antemortem drug concentrations from postmortem blood samples: the influence of postmortem redistribution: Table 1
Authors: Cook D S , Braithwaite R A , Hale K A 
Published: July 2002

Aims—To compare blood drug concentrations during life with postmortem drug concentrations measured from a peripheral site and a central site.Methods—Coroner's cases from October 1990 to July 1997 were reviewed. Six cases had data on both antemortem and postmortem blood drug concentrations. The postmortem to antemortem ratio was compared with the postmortem central to peripheral ratio, using cardiac blood as a central site and femoral blood as a peripheral site.Results—Drugs that have a high postmortem central to peripheral ratio; that is, drugs that exhibit considerable postmortem redistribution, also have high postmortem to antemortem ratios.Conclusions—A large degree of error can arise from attempting to estimate antemortem drug concentrations and the ingested dose from postmortem measurements. The chosen site and technique for postmortem blood sampling can greatly influence the concentration of drug measured.
Clinical ethics support services in the UK: an investigation of the current provision of ethics support to health professionals in the UK
Authors: Slowther Anne , Bunch Chris , Woolnough Brian , Hope Tony 
Published: July 2002

Objective—To identify and describe the current state of clinical ethics support services in the UK.Design—A series of questionnaire surveys of key individuals in National Health Service (NHS) trusts, health authorities, health boards, local research ethics committees and health professional organisations. Interviews with chairmen/women of clinical ethics committees identified in the surveys.Setting—The UK National Health Service.Results—Responses to the questionnaires were received from all but one NHS trust and all but one health authority/board. A variety of models of clinical ethics support were identified including twenty formal clinical ethics committees (CECs). A further twenty NHS trusts expressed an intention to establish a CEC within the next twelve months. Most CECs in the UK have been in existence less than five years and are still defining their role. The chairmen identified education of committee members and contact with other ethics committees as important requirements for committee development. Problems were identified around lack of support for the committee and with raising the profile of the committee within the institution. There has been little evaluation of clinical ethics support services either in the UK or in other countries with longer established services. What evaluation has occurred has focused on process rather than outcome measures.Conclusions—Clinical ethics support services are developing in the UK. A number of issues have been identified that need to be addressed if such support services are to develop effectively.
Laryngeal and hypopharyngeal cancers and occupational exposure to formaldehyde and various dusts: a case-control study in France
Authors: Laforest Laurent , Luce Danièle , Goldberg Paquerette , Bégin Denis , Gérin Michel , Demers Paul A , Brugère Jacques , Leclerc Annette 
Published: July 2002

OBJECTIVESA case-control study was conducted in France to assess possible associations between occupational exposures and squamous cell carcinomas of the larynx and hypopharynx.METHODSThe study was restricted to men, and included 201 hypopharyngeal cancers, 296 laryngeal cancers, and 296 controls (patients with other tumour sites). Detailed information on smoking, alcohol consumption, and lifetime occupational history was collected. Occupational exposure to seven substances (formaldehyde, leather dust, wood dust, flour dust, coal dust, silica dust, and textile dust) was assessed with a job exposure matrix. Exposure variables used in the analysis were probability, duration, and cumulative level of exposure. Odds ratios (ORs) with their 95% confidence intervals (95% CIs) were estimated by unconditional logistic regression, and were adjusted for major confounding factors (age, smoking, alcohol, and when relevant other occupational exposures).RESULTSHypopharyngeal cancer was found to be associated with exposure to coal dust (OR 2.31, 95% CI 1.21 to 4.40), with a significant rise in risk with probability (p<0.005 for trend) and level (p<0.007 for trend) of exposure. Exposure to coal dust was also associated with an increased risk of laryngeal cancer (OR 1.67, 95% CI 0.92 to 3.02), but no dose-response pattern was found. A significant relation, limited to hypopharyngeal cancer, was found with the probability of exposure to formaldehyde (p<0.005 for trend), with a fourfold risk for the highest category (OR 3.78 , 95% CI 1.50 to 9.49). When subjects exposed to formaldehyde with a low probability were excluded, the risk also increased with duration (p<0.04) and cumulative level of exposure (p<0.14). No significant association was found for any other substance.CONCLUSIONThese results indicate that exposure to formaldehyde and coal dust may increase the risk of hypopharyngeal cancer.
Hepatitis A in workers exposed to sewage: a systematic review
Authors: Glas C , Hotz P , Steffen R 
Published: July 2002

OBJECTIVESTo assess whether the scientific literature supports the hypothesis that workers exposed to sewage are at higher risk of hepatitis A (HA).METHODSAll original papers reporting epidemiological studies published in English, French, or German which reported on the risk of HA infection in workers exposed to sewage were eligible. They were identified by several methods and each original paper was assessed independently with a checklist by two people. Studies were classified according to the strength of their design. Non-eligible studies were also examined to assess the impact of publication bias. If the risk estimates diverged widely, causes for heterogeneity were assessed. A distinction was made between seroprevalence studies based on subclinical HA (defined only by the presence of anti-HA antibodies) and clinical HA.RESULTS17 eligible studies were identified. No indication of an increased risk of clinical HA could be found. For seroprevalence the studies with the strongest design suggested a slightly increased risk of subclinical HA with an odds ratio (OR) <2.5. Heterogeneity was considerable and precluded a meta-analysis. Considering non-eligible studies would still decrease the OR.CONCLUSIONSThe systematic review does not confirm an increased risk of clinical HA in workers exposed to sewage. An increased risk of subclinical HA cannot be excluded but the association between seropositivity and exposure to sewage was not strong and became still weaker if publication bias was taken into account.
Sensitisation to natural rubber latex: an epidemiological study of workers exposed during tapping and glove manufacture in Thailand
Authors: Chaiear N , Sadhra S , Jones M , Cullinan P , Foulds I S , Burge P S 
Published: July 2002

OBJECTIVESTo estimate the prevalence of sensitisation to natural rubber latex in latex tappers and latex glove factory workers, and to relate this to airborne exposure to latex.METHODSFive hundred workers employed in three latex glove factories, 314 tappers, and 144 college students (control group) were studied. The workers in the glove factories were classified into three exposure groups; high, moderate, and low. Personal exposures to natural rubber latex aeroallergens were measured by immunoassay. Symptom questionnaires and skin prick tests with latex allergens (Stallergènes 1:200 w/v) and other common environmental allergens were performed. The criterion for positivity was a wheal reaction at least 3 mm in diameter greater than that to a diluent control.RESULTSThe geometric mean (GM) concentration of latex in air was 15.4 μg/m3for those employed in glove stripping, glove inspections, and packing of powdered gloves. The moderate exposure glove manufacturing group and the tappers had GM concentrations of 2.3 and 2.4 μg/m3respectively, compared with United Kingdom users of latex powdered gloves,who had GM concentrations of 0.5 μg/m3. The prevalence of sensitisation to latex in the tappers and latex glove factory workers was 1.3% and 1.7% respectively. No positive cases were found among the college students. Workers who showed a positive skin prick test to latex were more likely to be atopic. Work related respiratory and dermatological symptoms were found in about 20% of each population studied, but were not related to the presence of positive latex prick tests.CONCLUSIONSThis study suggests that in the Thai latex industries, latex sensitisation is rare despite high concentrations of airborne exposure and is less prevalent than in the healthcare sector in Europe where skin exposure is greater.
Changes in rates and severity of compensation claims for asthma due to diisocyanates: a possible effect of medical surveillance measures
Authors: Tarlo S M , Liss G M , Yeung K S 
Published: July 2002

Objectives: A medical surveillance programme was introduced into Ontario for workers exposed to diisocyanates in 1983, but no mandated surveillance programme is in effect in this province for other occupational respiratory sensitisers. This study assesses changes in incidence and severity of compensated claims for occupational asthma (OA) due to diisocyanates compared with other causes, which have occurred since the introduction of this surveillance programme.Methods: New claims for OA compensated by the Ontario Workers' Compensation Board (WCB) between 1980 and 1993 were retrospectively reviewed. Linkage was made between these data and an Ontario Ministry of Health database to assess hospital admissions for asthma from the date of onset of OA until the end of 1996.Results: Numbers of claims for OA induced by diisocyanates ranged from 9–15/year in 1980–83, increased up to 55–58 claims/year in 1988–90, then fell to 19–20 claims/year by 1992–93. By contrast yearly numbers of claims for OA due to other causes increased up to 1985–87 then remained relatively stable. Duration of symptoms for OA induced by diisocyanates was shorter than for other claims and there were fewer hospital admissions among those with OA induced by diisocyanates than among those with OA induced by other causes. Occupational asthma from all causes was diagnosed earlier in claims for 1987–93 compared with 1980–86, and indicators of severity of asthma were also milder in accepted claims during 1987–93 than in earlier claims.Conclusions: Although engineering and industrial hygiene measures may have contributed to these changes, our findings are also consistent with a beneficial contribution from the medical surveillance programme for workers exposed to diisocyanates.
Silent myocardial ischaemia in patients with proved coronary artery disease: a comparison of diabetic and non-diabetic patients
Authors: Ditchburn C J , Hall J A , de Belder M , Davies A , Kelly W , Bilous R 
Published: July 2002

Abstract

OBJECTIVE
To determine whether diabetic patients with coronary artery disease are more likely to experience silent myocardial ischaemia than subjects without diabetes.

SUBJECTS
Patients undergoing coronary angiography at a regional cardiothoracic unit, identified as having diabetes from the local district diabetic register/database.

DESIGN
The coronary angiograms and exercise treadmill tests of 100 diabetic and 100 non-diabetic patients who all had significant coronary artery disease and maximal effort exercise tests were reviewed. Patients were individually matched for age group, gender, severity of coronary artery disease, and indication for treadmill test.

OUTCOME MEASURES
Significant coronary artery disease was defined as a stenosis of greater than 50% diameter in at least one of the major coronary artery segments. Exercise tests were graded as positive if the electrocardiographic (ECG) recording showed planar or downsloping ST segment depression of ⩾1 mm in more than two leads at 80 ms post J-point or if there was a blood pressure fall ⩾10 mm Hg after an initial rise. A negative exercise test was defined as one in which the subject experienced no pain, had no ECG changes after maximal effort and had a normal blood pressure response. Subjects who did not experience any form of typical angina-type pain during a positive exercise test were defined as having an episode of silent ischaemia. Patients with symptomatic ischaemia were those who experienced typical angina-type pain with accompanying ST segment changes. Patients with a negative exercise test were defined as having “undetermined ischaemia”. This category included all those without ECG evidence of myocardial ischaemia during the exercise test (with or without accompanying chest pain).

RESULTS
In the diabetic patients, 34% had ECG evidence of silent ischaemia on treadmill testing compared with only 19% of the non-diabetic controls (p&lt;0.02).

CONCLUSIONS
This study shows that diabetic patients with proved coronary artery disease have a higher risk of developing silent myocardial ischaemia during exercise than non-diabetic patients.
AUTOMORPHIC FORMS AND LORENTZIAN KAC–MOODY ALGEBRAS PART I
Authors: GRITSENKO VALERI A. , NIKULIN VIACHESLAV V. 
Published: July 2002

Using the general method which was applied to prove finiteness of the set of hyperbolic generalized Cartan matrices of elliptic and parabolic type, we classify all symmetric (and twisted to symmetric) hyperbolic generalized Cartan matrices of elliptic type and of rank 3 with a lattice Weyl vector. We develop the general theory of reflective lattices T with 2 negative squares and reflective automorphic forms on homogeneous domains of type IV defined by T. We consider this theory as mirror symmetric to the theory of elliptic and parabolic hyperbolic reflection groups and corresponding hyperbolic root systems. We formulate Arithmetic Mirror Symmetry Conjecture relating both these theories and prove some statements to support this Conjecture. This subject is connected with automorphic correction of Lorentzian Kac–Moody algebras. We define Lie reflective automorphic forms which are the most beautiful automorphic forms defining automorphic Lorentzian Kac–Moody algebras and formulate finiteness Conjecture for these forms. Detailed study of automorphic correction and Lie reflective automorphic forms for generalized Cartan matrices mentioned above will be given in Part II.
INVERSE RADIOTHERAPY TREATMENT PLANNING MODEL APPLYING BOLTZMANN-TRANSPORT EQUATION
Authors: TERVO JOUKO , KOLMONEN PEKKA 
Published: July 2002

In the external radiation therapy the source of radiation is from outside. The healthy tissue and some organs, called critical organs which are quite intolerable for radiation, are always irradiated, too. Therefore, the careful treatment plan has to be constructed to ensure high and homogeneous dose in the tumor, but on the other hand to spare the normal tissue and critical organs possibly well. In the radiation therapy treatment planning one tries to optimize the dose distribution in the way that the above aim is satisfied. The dose distributions can be generated with different techniques. The most recent of them is the so-called multileaf collimator (MLC) delivery technique. Calculation of the dose distribution demands some dose calculation model. The paper gives a model and theoretical basis of planning applying the Boltzmann-transport equation in dose calculation and MLC delivery technique. The existence of solutions and the optimal treatment planning are considered. A preliminary artificial computer simulation is included.
BIOLOGICAL RECEPTORS: IMPLICATIONS OF RADIOLIGAND QUALITY IN BINDING ASSAYS
Authors: VENTURINO ANDRÉS , RIVERA ELENA S. 
Published: July 2002

We tested the ability of different fitting procedures to discern differences in the binding affinity between the labeled and unlabeled ligand in a receptor assay, in order to obtain the correct value of the radiotracer specific activity. This point is critical for the correct conversion of the estimated binding constants to meaningful units. We simulated sets of receptor assays which considered distinct experimental situations, and fitted the data with two models considering either a unique or two different affinities for the two classes of ligand. We compared direct non-linear regression, linear robust regression on transformed data, and an experimental approach called pseudo-saturation (labeled plus unlabeled ligand in constant ratio) assay. It emerges from the results that none of these methods would be sensitive enough, even in commonly acceptable error levels in the measured variables, to indicate the appropriate model with a reasonable certainty. The a priori consideration of a different binding capacity for both categories of the ligand gives an acceptable estimation of the parameters, regardless of the fact that the fitting criteria reflect a better fitting of the other model. We conclude that a two-affinity binding model should be routinely fitted to experimental data and the binding constants compared to the simple binding model when the specific activity of the radiotracer needs to be assessed.