p53-dependent radiation-induced crypt intestinal epithelial cells apoptosis is mediated in part through TNF-TNFR1 system

Radiation induces apoptosis of crypt intestinal epithelial cells (IEC) through a pathway that is largely dependent on p53. However, exactly how p53 mediates IEC apoptosis is unclear. Studies in vitro suggest that one mechanism by which p53 mediates apoptosis is through its ability to transactivate members of the TNF receptor family of 'Death Receptors'. Here, we examined the role of one of its member, TNF receptor type 1 (TNFR1), in an in vivo model of p53-dependent radiation-induced IEC apoptosis. We demonstrate that mice genetically engineered to be deficient in TNF receptor type 1 (TNFR1(-/-)) and mice injected with TNFR1-fusion chimeric protein (TNFR1-Fc; a competitive inhibitor of TNFR1) were partially protected (30-40%) from p53-dependent radiation-induced IEC apoptosis. However, we found no evidence to support the possibility p53 transcriptionally regulates the expression of TNFR1 nor increases the susceptibility of IEC to TNF-mediated apoptosis. Interestingly, we found that injection of TNF readily induced IEC apoptosis and that radiation induced a p53-dependent increase in the intestinal level of TNF. Furthermore, injection of a neutralizing anti-TNF mAb reduced p53-dependent radiation-induced IEC apoptosis by approximately 60%. Overall, these results suggest that p53-dependent radiation-induced IEC apoptosis is mediated in part through ability of p53 to regulate TNF, which subsequently induces IEC apoptosis through TNFR1.

Structural organization of the human NBC1 gene: kNBC1 is transcribed from an alternative promoter in intron 3

Several electrogenic sodium bicarbonate cotransporters have been cloned from different human organs. In the renal proximal tubule, the electrogenic sodium bicarbonate cotransporter kNBC1 (1035aa) mediates the majority of basolateral sodium bicarbonate absorption. In pancreatic ducts, the electrogenic sodium bicarbonate cotransporter pNBC1 (1079aa) mediates basolateral sodium bicarbonate influx. hNBC1 (hhNBC), cloned from human heart, is identical to pNBC1 at the amino acid level. We have demonstrated that kNBC1 and pNBC1 are highly homologous proteins that have different N-termini. In kNBC1, 41 amino acids replace the initial 85 amino acids of pNBC1. Whether these proteins are coded by one or more genes is unknown. In order to determine the genetic basis for these transcripts, we first characterized the genomic organization of the NBC1 gene (SLC4A4). NBC1 spans approximately 450 kilobases containing 26 exons that are flanked by typical splice donor and acceptor sequences at the intron-exon boundaries. Exon 1 is specific for the pNBC1 transcript. The first alternative exon of the hNBC1 transcript, containing the 5'-untranslated region, is derived from the last 43 nucleotides of intron 1 in the NBC1 gene coupled to exon 2. kNBC1 is transcribed from an alternative promoter in intron 3. In the first alternative exon of kNBC1, the last 313 nucleotides of intron 3 are coupled to exon 4, which is common to pNBC1 and hNBC1. The major transcription initiation site in kNBC1 is located 192 nucleotides upstream from the translation initiation codon. A minor start site is located 182 nucleotides upstream from the translation initiation codon. Structural analysis of the proximal kNBC1 promoter revealed an atypical TATA sequence (-33) and several potentially important transcription factor binding sites. Functional studies showed that the 5'-flanking region of the alternative kNBC1 promoter (-159 to+43) is sufficient for promoter activity. This work is the first demonstration that the three N-terminal transcripts of the human electrogenic sodium bicarbonate cotransporter NBC1 are encoded by the SLC4A4 gene. Furthermore, knowledge of the genomic organization and alternative promoter usage in the NBC1 gene provides a molecular basis for understanding disorders involving electrogenic sodium bicarbonate cotransporters and facilitates the elucidation of transcriptional control of NBC1 expression.

Role of acidic sphingomyelinase in Fas/CD95-mediated cell death

Engagement of the Fas receptor has been reported to induce ceramide generation via activation of acidic sphingomyelinase (aSMase). However, the role of aSMase in Fas-mediated cell death is controversial. Using genetically engineered mice deficient in the aSMase gene (aSMase(-/-)), we found that thymocytes, concanavalin A-activated T cells, and lipopolysaccharide-activated B cells derived from both aSMase(-/-) and aSMase(+/+) mice were equally sensitive to Fas-mediated cell death, triggered by either anti-Fas antibody or Fas ligand in vitro. Similarly, activation-induced apoptosis of T lymphocytes was unaffected by the status of aSMase, and aSMase(-/-) mice failed to show immunological symptoms seen in animals with defects in Fas function. In vivo, intravenous injection of 3 microg/25 g mouse body weight of anti-Fas Jo2 antibody into aSMase(-/-) mice failed to affect hepatocyte apoptosis or mortality, whereas massive hepatocyte apoptosis and animal death occurred in wild type littermates. Animals heterozygous for aSMase deficiency were also significantly protected. Susceptibility of aSMase(-/-) mice to anti-Fas antibody was demonstrated with higher antibody doses (>/=4 microg/25 g mouse). These data indicate a role for aSMase in Fas-mediated cell death in some but not all tissues.

Mental health. Facing hard truths

A survey of 104 mental health units found that half did not have policies on treatment of detained patients from black and ethnic minority groups. Almost three-quarters had no policy for dealing with racial harassment of black and ethnic-minority patients. 11 percent of patients whose notes were examined had reported racial harassment.

Clusters of new tuberculosis cases in North-west London: a survey from three hospitals based on IS6110 RFLP typing

OBJECTIVES

The relative contributions of reactivation of latent infection and clusters of new infections to the overall incidence of tuberculosis in the U.K. is unknown. A study was carried out in North-West London to determine the feasibility of IS6110 RFLP strain typing as a tool to investigate the relative contributions of these two sources.

METHODS

All available isolates of M. tuberculosis from specimens collected over a calendar year at three participating hospitals were typed by RFLP using an IS6110 probe. Isolates exhibiting a single band pattern were subject to further typing using an oligonucleotide direct repeat probe. Demographic and clinical information on cases was obtained from the National Survey of Tuberculosis Notifications in England and Wales and further information sought on clustered cases as identified by RFLP typing.

RESULTS

Twenty-seven (23%) of the 118 cases had shared IS6110 RFLP patterns. Strains from nine cases had single band patterns, but these were all distinguishable from each other when subjected to further typing by direct repeat probe. The remaining 18 cases belonged to eight clusters. Epidemiological links were established between all the patients in each cluster. The likelihood of being in a cluster was increased in cases with pulmonary smear-positive disease. It was lower in cases of Indian Sub-continent ethnic origin. For 10 of the 18 clustered cases epidemiological links had not been established by conventional contact tracing.

CONCLUSIONS

Investigation of the relative contributions of reactivation of latent infection and new infection is feasible in a UJK population, using IS6110 RFLP typing of M. tuberculosis isolates and epidemiological enquiries. This study in London identified clustered, presumably new cases, the majority of whom had not been linked epidemiologically. Comprehensive IS6110 RFLP typing of UK isolates would probably identify many clusters of incident tubercular infection.

Professional roller hockey injuries

OBJECTIVE

To study the incidence and types of injuries sustained by professional roller hockey players in practices and games, and to compare these statistics with those from ice hockey.

DESIGN

This injury survey used a strict definition of injury, standardized reporting strategies, and diagnosis by a team physician as standards by which to analyze the characteristics of roller hockey injuries.

SETTING

The injuries were recorded after the players had been examined by a team physician at the game or practice site or in the physician's office.

PARTICIPANTS

During three seasons for one roller hockey team and one season for another team, an average of 22 players per team participated in the study. Due to personnel changes, the team rosters were modified between seasons. Each player injury was included in the study. An injury was defined as any physical impairment caused during a practice or game that eliminated the player from that practice or game or the next day's practice session or contest, or any physical ailment that necessitated a physical examination by the team physicians.

MAIN OUTCOME MEASURE

Injury data were categorized and injury rates were calculated.

RESULTS

122 injuries were recorded during four professional roller hockey seasons, resulting in an overall participation injury rate of 14.4 per 1,000 player hours. The game injury rate was 304.9 per 1,000 player hours. The players were 105.1 times more likely to be injured during a game than during practice. Preseason practices produced 4.5 times more injuries than regular season practices. In comparison, sample data from the only other published study of roller hockey injuries and from several studies of ice hockey have indicated game injury rates of 139.0 (roller hockey), 119.0, 96.1, 78.4, 78.8, and 66.0 per 1,000 player hours, respectively.

CONCLUSION

Results of this study demonstrate that roller hockey produces a higher rate of both contact and noncontact injuries than ice hockey; this contradicts the findings of the only other published research study on injuries in roller versus ice hockey. This increased incidence of injury may be due in part to the differences in surfaces, and can prove hazardous to even the recreational roller hockey player or in-line skater.

Otoacoustic emission findings in Rett syndrome

Rett syndrome is a neurologic disorder affecting mainly females after a seemingly normal 6 to 18 months of life. The resulting developmental disabilities include apparent dementia and loss of acquired language, social skills, and purposeful hand use. The present investigation assessed 10 individuals with Rett syndrome and a control group matched for age and sex. The present study aimed to determine the clinical feasibility of obtaining otoacoustic emissions (OAEs) from the Rett syndrome group and to compare the characteristics of the transient evoked and distortion-product OAEs obtained from the two subject groups. Results indicated that OAE evaluation is a clinically feasible method of assessing individuals with Rett syndrome. The Rett syndrome group had less robust OAEs, especially in the higher frequencies, when compared to the control group. Seven of the Rett syndrome group were identified as having reduced or absent OAEs in at least one ear. These findings suggest a need for hearing screening at an early age and monitoring of hearing on a regular basis.

Risk factors for laparoscopically confirmed pelvic inflammatory disease: findings from Mumbai (Bombay), India

OBJECTIVES

Sexually transmitted diseases (STDs) are an important cause of pelvic inflammatory disease (PID) but have often not been detected in microbiological studies of Indian women admitted to hospital gynaecology wards or private clinics. In this cross sectional study, women living in the inner city of Mumbai (Bombay) were investigated for socioeconomic, clinical, and microbiological risk factors for PID.

METHODS

Microbiological tests and laparoscopic examination were carried out on 2736 women aged < or = 35 years who came to a health facility with suspected acute salpingitis or infertility or for laparoscopic sterilisation. 86 women with a clinical diagnosis of PID were not referred for laparoscopy although their characteristics are described. Associations between various risk factors and PID status were investigated and logistic regression performed on all factors that remained significant.

RESULTS

Of women with a laparoscopically confirmed evaluation, 26 women had acute and 48 chronic pelvic infection. Independent risk factors for PID were later age at menarche (> or = 14 years), a history of stillbirth and no previous pregnancy, history of tuberculosis, STD, dilatation and curettage or previous laparoscopy, and presence of Gardnerella vaginalis.

CONCLUSIONS

It is concluded that STD related risk factors applied to only a small proportion of PID cases and that other determinants of PID are important, including obstetric complications, invasive surgical procedures such as laparoscopy, and tuberculosis.

Reproductive tract infections, gynaecological morbidity and HIV seroprevalence among women in Mumbai, India

Reported are the prevalence of reproductive tract infections and their contribution to pelvic inflammatory disease (PID), as well as the seroprevalence of human immunodeficiency virus (HIV), among women living in three inner city wards of Mumbai, India. Women aged < or = 35 years were recruited and screened as cases if they had been admitted to hospital for gynaecological investigation for suspected PID (n = 151) or infertility (n = 295); controls were healthy fertile women attending for laparoscopic tubal ligation (n = 2433). The women were mainly of low socioeconomic status. A total of 59.4% were migrants and 14.9% of these came to Mumbai to seek treatment. Cases reported a history of adverse pregnancy outcomes significantly more often than controls, and 30.5% of suspected PID cases had previously undergone laparoscopic tubal ligation. At examination 24.2% of cases and 8.4% of controls had a vaginal discharge. Pelvic infection was confirmed in 42.0% of suspected PID cases and 14.6% of infertile cases for whom diagnostic laparoscopy was performed. The prevalence of sexually transmitted diseases was low: Chlamydia trachomatis was found in 0.2%; and Neisseria gonorrhoeae was cultured from the cervix in only four cases. Neither of these infections was detected in laparoscopic aspirates. The prevalence of HIV1/2 infections in unlinked samples was 1.9%. Sexually transmitted diseases were not major factors leading to gynaecological morbidity. Heterosexual spread of HIV infection to this population of married women is still relatively low but needs to be carefully monitored. The gynaecological morbidity detected may be a consequence of widespread use of invasive methods of fertility regulation.

Tuberculosis in England and Wales in 1993: results of a national survey. Public Health Laboratory Service/British Thoracic Society/Department of Health Collaborative Group

BACKGROUND

A national survey of tuberculosis notifications in England and Wales was carried out in 1993 to determine the notification rate of tuberculosis and the trends in the occurrence of disease by ethnic group in comparison with the findings of similar surveys in 1978/79, 1983, and 1988. The prevalence of HIV infection in adults notified with tuberculosis in the survey period was also estimated.

METHODS

Clinical, bacteriological, and sociodemographic information was obtained on all newly notified cases of tuberculosis in England and Wales during the six months from 2 January to 2 July 1993. The prevalence of HIV infection in 16-54 year old patients with tuberculosis notified throughout 1993 was assessed using "unlinked anonymous" testing supplemented by matching of the register of patients with tuberculosis with that of patients with AIDS reported to the PHLS AIDS centre. Annual notification rates were calculated using population estimates from the 1993 Labour Force Survey.

RESULTS

A total of 2706 newly notified patients was eligible for inclusion in the survey of whom 2458 were previously untreated the comparable figures for 1988 were 2408 and 2163. The number of patients of white ethnic origin decreased from 1142 (53%) in 1988 to 1088 (44%) in 1993 whereas those of patients of Indian, Pakistani, or Bangladeshi (Indian subcontinent (ISC)) ethnic origin increased from 843 (39%) in 1988 to 1014 (41%) and those of "other" (non-white, non-ISC) ethnic origins increased from 178 (8%) to 356 (14%). The largest increase was seen in the black African ethnic group from 37 in 1988 to 171 in 1993. Forty nine per cent of patients had been born abroad and the highest rates were seen in those who had recently arrived in this country. The overall annual notification rate for previously untreated tuberculosis in England and Wales increased between 1988 and 1993 from 8.4 to 9.2 per 100,000 population. The rate declined in the white, Indian, and black Caribbean ethnic groups and increased in all other groups. In the white group the rate of decline has slowed since the last survey: in several age groups the rates were higher in 1993 than 1988 but the numbers in these groups were small. Thirty six (4.1%) of the 882 previously untreated respiratory cases were resistant to isoniazid and three (0.3%) to isoniazid and rifampicin. Sixty two (2.3%) adults aged 16-54 years were estimated to be HIV-infected. Evidence of under-reporting of HIV positive tuberculosis patients was found.

CONCLUSIONS

The number of cases and annual notification rate for previously untreated tuberculosis increased between 1988 and 1993. Although the decline in rates in the white population has continued, the rate of decline has slowed. The high rates in the ISC ethnic group population have continued to decline since 1988 whereas rates in the black African group have increased. An increased proportion of cases were found among people born abroad, particularly those recently arrived in this country. In previously untreated cases the level of drug resistance remains low and multi-drug resistance is rare. A small proportion of adults with tuberculosis were infected with HIV but there may be selective undernotification of tuberculosis in these patients.

Study of the effectiveness of influenza vaccination in the elderly in the epidemic of 1989-90 using a general practice database

The effectiveness of influenza vaccination in preventing serious illness and death was determined in an elderly population during the influenza epidemic of was determined in an elderly population during the influenza epidemic of was determined in an elderly population during the influenza epidemic of 1989-90. A retrospective cohort study was carried out using computerized general practitioner records on nearly 10,000 patients aged 55 years and over. After adjustment for potential confounding factors, recent immunization was found to have a protective effect of 75% (95% confidence intervals: 21-92%) against death. Protection did not appear to vary with either age or the presence of underlying chronic disease. As the complications of influenza are most common in those with underlying chronic disease, the study findings are consistent with the recommended policy for the use of influenza vaccine in the UK. Further work is necessary to determine the cost-effectiveness of extending immunization to other groups.

The Public Health Laboratory Service national case-control study of primary indigenous sporadic cases of campylobacter infection

The aetiology of sporadic campylobacter infection was investigated by means of a multicentre case-control study. During the course of the study 598 cases and their controls were interviewed. Conditional logistic regressional analysis of the data collected showed that occupational exposure to raw meat (odds ratio [OR] 9.37; 95% confidence intervals [CI] 2.03, 43.3), having a household with a pet with diarrhoea (OR 2.39; CI 1.09, 5.25), and ingesting untreated water from lakes, rivers and streams (OR 4.16; CI 1.45, 11.9) were significant independent risk factors for becoming ill with campylobacter. Handling any whole chicken in the domestic kitchen that had been bought raw with giblets, or eating any dish cooked from chicken of this type in the home (OR 0.41-0.44; CI 0.24, 0.79) and occupational contact with livestock or their faeces (OR 0.44; CI 0.21, 0.92) were significantly associated with a decrease in the risk of becoming ill with campylobacter.

A collaborative case control study of sporadic hepatitis A in England

A case control study of sporadic hepatitis A was carried out in 201 districts in England from July 1990 to June 1991. The aims were to determine the risk factors associated with the infection and to identify individuals or groups who might benefit from prophylactic measures, such as human normal immunoglobulin or hepatitis A vaccine. Factors associated with risk of hepatitis A included travel abroad (odds ratio (OR) 19.8; 95% confidence interval (CI) 4.87-80.6), a household contact with hepatitis A (OR 13.5; 95% CI 6.49-28.0) and sharing a household with a child aged 3 to 10 years (OR 1.57; 95% CI 1.1-2.22). This study provided no clear evidence of increased risk in health care workers, teachers, or other occupational groups. A non-significant trend towards an increased risk in nursery nurses and child minders aged 20 to 29 years was observed. Pre-exposure prophylaxis with hepatitis A vaccine may be considered for people who travel frequently to areas where hepatitis A is highly or moderately endemic. Post-exposure prophylaxis with human normal immunoglobulin should be given to contacts of known cases in accordance with national guidelines. Immunoglobulin alone has been recommended in outbreaks, but the use of vaccine alone or combined with immunoglobulin should be evaluated.

Survey of human immunodeficiency virus infection among pregnant women in England and Wales: 1990-93

We report on the first four years (1990-93) of a survey within the national HIV prevalence monitoring programme. The survey's objective is to monitor the prevalence of infection with the human immunodeficiency virus (HIV) in pregnant women in London and elsewhere in England. The survey--based in forty centres that offer antenatal care in London, Greater Manchester, West Yorkshire, and adjacent non-metropolitan areas--uses repeated cross sectional serosurveillance for anti-HIV-1 and 2 and the unlinked anonymous test method on blood left over from specimens collected for antenatal screening for immunity to rubella. The seroprevalence of HIV-1 ranged from 0.007% (1 in 14,530) in non-metropolitan areas, to 0.011% (1 in 8790) in metropolitan areas outside London, and 0.23% (1 in 440) in London. Evidence of HIV-2 infection was found in only four specimens, in London (1 in 50,300). The seroprevalence of HIV-1 in London varied more than tenfold between centres, from 0.03% (1 in 3190) to 0.51% (1 in 200). The highest prevalence of infection was in London in women aged between 20 and 30 (0.30%; 1 in 335). The seroprevalence in London centres rose from 0.18% in 1990 (1 in 560) to 0.26% in 1993 (1 in 390) and the rise was significant in all age groups. If voluntary confidential HIV testing (with counselling) among pregnant women in England were to be promoted, its cost effectiveness would be greater if focused on particular centres that provide antenatal care in London.