Ordered tandem arrangement of chromosomes in the sperm heads of monotreme mammals

A very old unanswered question in classical cytology is whether chromosomes are arranged randomly in sperm or whether they occupy specific positions. Even with modern methods of chromosome painting, it is difficult to resolve this question for the very condensed and almost spherical sperm head of most mammals. We have taken advantage of the unusual fibrillar sperm head of monotreme mammals (echidna and platypus) to examine the position of chromosome landmarks in a two-dimensional array. We used fluorescence and radioactive in situ hybridization to telomeric, rDNA, and unique sequences to show that chromosomes are arranged tandemly and in a defined order in the sperm nucleus.

Prevention of disability and rehabilitation--results from a collaborative project in China

Eight different geographical districts in China varying in urban and rural characteristics from 6 provinces and 2 municipalities were selected as pilot areas of the project. The interventions included early detection and treatment of neuritis, self-care training, adapted footwear, surgery, comprehensive treatment of complicated ulcers, and prostheses. Main changes in eye, hand and foot impairments between baseline assessment and assessment at 2 years have been presented in this paper.

Are healthcare workers in England and Wales at increased risk of tuberculosis?

OBJECTIVE

To determine whether healthcare workers in England and Wales are at increased risk of tuberculosis and to examine the frequency of drug resistance in this population.

DESIGN

Comparison of notification rates by occupation obtained from national tuberculosis notification surveys in 1988 and 1993, with denominators from the 1991 census.

SUBJECTS

People with notified tuberculosis in professional and associate professional occupations from the two surveys.

MAIN OUTCOME MEASURES

Rates of notified tuberculosis in health professionals (mainly doctors) and health associate professionals (mainly nurses) compared with rates in other professional and associate professional occupations, adjusted for ethnic group, sex, and age.

RESULTS

119 cases of tuberculosis were identified in healthcare workers, including 61 nurses and 42 doctors. The crude notification rate in healthcare workers was 11.8 per 100,000 per year (95% confidence interval 9.8 to 14.1) compared with 3.3 per 100,000 per year (2.9 to 3.6) in other professional and associate professional occupations; rate ratios were higher (range 1.7 to 3.2) in all ethnic groups. The relative risk adjusted for ethnic group, sex, and age was 2.4 (95% confidence interval 2.0 to 3.0), slightly higher for health professionals (2.7 (1.9 to 3.8)) than for associate professionals (2.0 (1.5 to 2.6)). No multiple drug resistant strains of tuberculosis were identified in healthcare workers.

CONCLUSIONS

Better detection and notification of cases of tuberculosis in healthcare workers may account for some of the apparent increased risk, but these findings imply that tuberculosis remains a hazard for healthcare workers and highlight the importance of ensuring that occupational health monitoring and protection workers are not neglected.

Comparative mapping identifies the fusion point of an ancient mammalian X-autosomal rearrangement

Previous comparisons of gene location in the three major groups of mammals (eutherians, marsupials, and monotremes) have suggested that the long arm of the human X represents the ancestral mammalian X chromosome, whereas the short arm represents an autosomal region(s) recently added to the eutherian X chromosome. To identify the fusion point of this ancient X-autosome rearrangement, we have mapped four genes, three of which map near the centromere of the human Xp, in marsupials and in a monotreme. We found that ARAF1, ALAS2, and GATA1 are located on the X chromosome in marsupials, and ALAS2 and GATA1 are also located on the X in the platypus. This implies that the proximal short arm of the human X chromosome, including the centromere, was part of the ancestral mammalian X chromosome. The fusion point between the conserved region and the recently added regions therefore maps to human Xp11.23, although gene order on the human X indicates that there has been some rearrangement of this region.

Evolution of the mammalian mitochondrial control region--comparisons of control region sequences between monotreme and therian mammals

The platypus mitochondrial control region has been cloned and sequenced. Comparative analysis of this sequence with the published control region sequences of several other mammalian species has identified regions of sequence consensus that are conserved throughout the Mammalia. Regions predicted to form thermodynamically stable secondary structures in the platypus are also homologous to such putative structures in other species. In addition to these conserved structures, the platypus mitochondrial control region also contains a number of unusual features, including two regions of repetitive sequence, one of which gives rise to pronounced length variation between animals. Possible functions for the conserved structures and a mechanism for the generation of the control region length variation are proposed with respect to our current understanding of mitochondrial replication and transcription.

Surveillance of tuberculosis in Europe. Working Group of the World Health Organization (WHO) and the European Region of the International Union Against Tuberculosis and Lung Disease (IUATLD) for uniform reporting on tuberculosis cases

Consensus-based recommendations have been developed by a Working Group of the World Health Organization (WHO) and the European Region of the International Union Against Tuberculosis and Lung Disease (IUATLD) on uniform reporting of tuberculosis surveillance data in the countries of Europe. A uniform case definition and a minimum set of variables for reporting on each case have been agreed which, when collated on a national basis, will allow comparison of the epidemiology of tuberculosis in different European countries. The Working Group recommends that the case definition includes "definite" cases, where the diagnosis has been confirmed by culture (or supported by microscopy findings in countries where diagnostic culture facilities are not available), and "other than definite cases" based on a clinical diagnosis of tuberculosis combined with the intention to treat with a full course of antituberculosis therapy. Both "definite" and "other than definite" cases should be notified by physicians and, in addition, laboratories should be required to report "definite" cases. The minimum set of variables to be collected on each case of tuberculosis should include: date of starting treatment, place of residence, date of birth, gender, and country of origin, to characterize the patient. Recommended disease-specific variables include: site of disease, bacteriological status (microscopy and culture), and history of previous antituberculosis chemotherapy. The minimum set of variables should be collated on all patients and should be as complete as possible. Additional variables may be collected for individual, local or national purposes, but, in general, completeness of reporting on cases is likely to be better if the information requested is kept to a minimum. Timely reporting of cases is essential for appropriate public health action. Cases should be reported to the health authority at the local and/or regional level within 1 week of starting treatment. Individual-case based information should be reported to the national level by the local or regional level. Feedback to reporters is essential. At the national level, preliminary quarterly reports should be produced and final reports should be published annually.

Selective or universal neonatal BCG immunization: what policy for a district with a high incidence of tuberculosis?

In the United Kingdom, BCG immunization of neonates provides good protection against military and meningeal disease, and probably against other forms of tuberculosis, in all ethnic groups. Serious adverse reactions to BCG immunization are rare. Cost-effectiveness studies of BCG immunization in neonates have not been reported and "universal' BCG immunization is not recommended in the United Kingdom. The Department of Health does recommend immunization for children and infants of immigrants from countries with a high prevalence of tuberculosis. There are problems associated with such a "selective' policy, as determining what is "high' prevalence and thus defining "at risk' groups is difficult, and there may be political and practical difficulties in its implementation. This may result in low coverage in eligible groups. A "universal' policy of BCG immunization for all neonates may be politically more acceptable and easier to implement in districts with high tuberculosis notification rates. Although there is no cost-effectiveness data to determine at what tuberculosis notification rate a universal policy should be adopted, an universal policy has been suggested for districts with overall notification rate of greater than 40 per 100,000. Within districts there may be large variations in tuberculosis notification rates between different areas. This is becoming more common with the amalgamation and merger of smaller districts into new larger purchasing organizations. New River Health Authority is such a district formed by the amalgamation of the former districts of Haringey with a high tuberculosis notification rate, and Enfield with a lower TB notification rate. In order to maximize coverage in the "at risk' neonates, a different neonatal BCG policy has been adopted in the two areas. This has been possible because of the flexibility of the mechanisms for contracting with different provider units. Although the overall notification rate was not thought to be sufficiently high to justify a "universal' neonatal policy throughout the district, a "universal' policy has been instituted in the main provider unit in the former district Haringey. A "selective' policy, subject to ongoing evaluation to ensure high coverage, continues to be operated by the main provider unit in the former district of Enfield.

Influenza surveillance in England and Wales: October 1994 to June 1995

This report summarises the information obtained by surveillance of influenza in England and Wales from October 1994 to June 1995 (weeks 40/94 to 25/95). Influenza B viruses were responsible for most infections, with moderate activity occurring throughout the winter, peaking in February. Influenza A became more active towards the end of the winter, and laboratory reports reached a peak in May (week 21/95). Influenza activity was seen first in Wales, then England, followed by Scotland. An increase in 'total respiratory disease' was reported in December 1994 by the Birmingham Research Unit of the Royal College of General Practitioners (RCGP) in England and Wales. This was probably due largely to an increase in reports of acute bronchitis, and was concurrent with the annual increase in respiratory syncytial virus infection which is often associated with bronchiolitis. Circulating influenza viruses were antigenically similar to components of the vaccine chosen for 1994/95. This report summarises the recommendations for the 1995/96 influenza vaccine.

Prevention of impairment in leprosy; results from a collaborative project in China

OBJECTIVE

to evaluate programs of prevention and treatment of impairments due to leprosy in 8 geographical areas in the People's Republic of China.

DESIGN

follow up of cohorts of leprosy patients receiving a range of different interventions.

SETTING

8 different geographical areas in China, varying in urban and rural characteristics from 6 provinces and 2 municipalities.

SUBJECTS

leprosy patients who were receiving or had completed a course of antileprosy chemotherapy.

INTERVENTIONS

a range of interventions, including steroids, self-care training, adapted footwear, surgery and provision of prostheses.

MAIN OUTCOME MEASURES

changes in eye, hand and foot impairments between baseline assessment and assessment at 2 years.

RESULTS

232 out of 3571 patients assessed monthly over 2 years developed acute neuritis and, in most areas, were promptly and adequately treated. Regular self care of eyes was established in 238 out of 313 patients with lagophthalmos and was associated with reduction in the prevalence of conjunctivitis. Regular self care of hands was established in 730 out of 1010 patients with neurological impairment of the hand; this was associated with a reduction (80%) in hand cracks and wounds. Regular self care of feet was established in 745 out of 1094 patients with neurological impairment of the feet; this was associated with a 83% reduction in patients with cracks and a 33% reduction in patients with sole wounds. A footwear program was established in all 8 areas providing footwear to 4698 patients over the 2-year period; this was associated with a reduction of 61% and 21% in patients with cracks and wounds, respectively. Management of complicated sole wounds in 256 patients resulted in 69% of these patients being free of sole wounds at 2 years. Targets for reconstructive surgery and amputations were not fully attained, but lower limb prostheses were provided for 306 patients.

CONCLUSIONS

leprosy is a chronic disease characterized by peripheral neuropathies which can result in increasing secondary impairments and disabilities. The emphasis, in countries such as China where the chemotherapy programs have been effectively implemented, is shifting to prevention and treatment of impairments. This innovative program in China has successfully demonstrated that it is possible to prevent and reverse impairments due to leprosy.

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.

Tuberculosis among the homeless at a temporary shelter in London: report of a chest x ray screening programme

STUDY OBJECTIVE

To estimate the prevalence of active pulmonary tuberculosis in a homeless population in London and to assess whether those with suspected disease could be integrated into the existing health care system for further follow up and treatment.

DESIGN

Voluntary screening programme based on a questionnaire survey and chest x ray. SETTING AND CASES: Screening programmes were set up over the Christmas period in 1992 and 1993 at a shelter for the homeless in London. An offer of screening was made to all individuals who visited the centre and an interviewer administered questionnaire was completed on those who volunteered for the screening. Chest x rays were carried out, developed, and read on site. Individuals with chest x rays features suggestive of tuberculosis or other medical problems were referred to a hospital of their choice. RESULTS AND OUTCOME: In 1992 nearly 1600 people visited the centre, of whom 372 volunteered for the screening and 342 were x rayed. Nineteen of the 342 (5.6%) had radiological features suggestive of active tuberculosis. In 1993 around 2000 homeless people visited the centre, of whom 270 volunteered for the screening and 253 were x rayed. Eleven (4.3%) had features consistent with active tuberculosis on the basis of the chest x rays and clinical examination by a chest physician. Overall, of 595 people x rayed in the two surveys, 30 (5%) had changes suggestive of active tuberculosis. Further investigations confirmed nine (1.5%) with active pulmonary disease and eight with no active tuberculosis. In 13, the diagnosis was not determined as four declined further investigation and nine did not attend their hospital appointment.

CONCLUSION

Tuberculosis among the homeless remains a cause for concern. Follow up and treatment present unique difficulties. Services for the homeless need to include mechanisms for timely diagnosis and monitored treatment. Control programmes designed for the needs of the homeless are required.

Legionnaires' disease surveillance: England and Wales 1994

One hundred and sixty cases of legionnaires' disease in England and Wales were reported to the PHLS Communicable Disease Surveillance Centre in 1994, a rate of 3.1 cases per million population. Twenty-seven cases died. Eighty-nine cases (56%) were associated with travel, either in the United Kingdom (UK) or abroad, and six with a stay in hospital; the remaining cases were presumed to have acquired infection in the community. Seven outbreaks were detected in England and Wales: one was associated with a holiday centre, one with a hotel in London, two with industrial sites, and three occurred in the community. A further four clusters were associated with travel abroad: Spain, Ibiza, the Channel Islands, and a Mediterranean cruise. One hundred and twenty-eight of the 160 cases (79%) were sporadic--that is, not known to be associated with outbreaks--43 of which (34%) were not associated with travel nor acquired in hospital.

The intracellular IL-1 receptor antagonist alters IL-1-inducible gene expression without blocking exogenous signaling by IL-1 beta

The epithelium-associated tissue distribution of the intracellular IL-1R antagonist (icIL-1Ra) suggests that it functions as a novel regulatory molecule for IL-1 in somatic tissues. We examined the role of the icIL-1Ra in IL-1 beta-induced responses in human ovarian cancer cells because ovarian surface epithelium expresses transcripts for the icIL-1Ra, and the majority of ovarian cancers arise from these cells. Several human ovarian and cervical cancer cell lines spontaneously express the icIL-1Ra. icIL-1Ra-expressing cells did not have altered growth characteristics or altered short term responses to IL-1 compared with icIL-1Ra-nonexpressing cells. While a 90-min exposure to IL-1 beta resulted in increased steady state cytokine mRNA levels in all cells, icIL-1Ra-positive cells were incapable of maintaining IL-1-beta-induced expression of GRO mRNA. This did not result from decreased transcriptional activity of the GRO gene, but reflected differences in mRNA stability and/or degradation. To determine whether the icIL-1Ra altered mRNA stability, we used a retroviral expression vector to express the icIL-1Ra in an icIL-1Ra-negative cell line. The resulting cells displayed a profile of IL-1 beta-induced genes analogous to that found in cells spontaneously expressing icIL-1Ra. These data show for the first time an intrinsic biologic activity for the icIL-1Ra. The capacity to selectively alter IL-1-induced gene expression suggests that this version of the IL-1Ra is a unique intracellular inhibitor that attenuates IL-1 responses at a point downstream of the initial IL-1/IL-1 receptor interaction.

The intracellular IL-1 receptor antagonist alters IL-1-inducible gene expression without blocking exogenous signaling by IL-1 beta

The epithelium-associated tissue distribution of the intracellular IL-1R antagonist (icIL-1Ra) suggests that it functions as a novel regulatory molecule for IL-1 in somatic tissues. We examined the role of the icIL-1Ra in IL-1 beta-induced responses in human ovarian cancer cells because ovarian surface epithelium expresses transcripts for the icIL-1Ra, and the majority of ovarian cancers arise from these cells. Several human ovarian and cervical cancer cell lines spontaneously express the icIL-1Ra. icIL-1Ra-expressing cells did not have altered growth characteristics or altered short term responses to IL-1 compared with icIL-1Ra-nonexpressing cells. While a 90-min exposure to IL-1 beta resulted in increased steady state cytokine mRNA levels in all cells, icIL-1Ra-positive cells were incapable of maintaining IL-1-beta-induced expression of GRO mRNA. This did not result from decreased transcriptional activity of the GRO gene, but reflected differences in mRNA stability and/or degradation. To determine whether the icIL-1Ra altered mRNA stability, we used a retroviral expression vector to express the icIL-1Ra in an icIL-1Ra-negative cell line. The resulting cells displayed a profile of IL-1 beta-induced genes analogous to that found in cells spontaneously expressing icIL-1Ra. These data show for the first time an intrinsic biologic activity for the icIL-1Ra. The capacity to selectively alter IL-1-induced gene expression suggests that this version of the IL-1Ra is a unique intracellular inhibitor that attenuates IL-1 responses at a point downstream of the initial IL-1/IL-1 receptor interaction.

BCG--mass or selective vaccination?

After years of decline, notifications of tuberculosis in England and Wales have recently increased. BCG immunization forms part of the programme of measures to control tuberculosis in this country. All tuberculin negative 10-13-year-old schoolchildren are offered vaccination. In addition BCG is offered selectively at any age to those considered to belong to groups at increased risk of tuberculosis. While the protective effect of BCG immunization in the population of this country is well established, the cost-effectiveness of the School's BCG programme has been the subject of considerable debate. If the rate of tuberculosis notifications in the 15-29-year-old age group within the white majority population, the major group to whom any potential benefit of the Schools' programme applies, continues to decline, serious consideration should be given to discontinuing this programme while strengthening the programme of selective immunization.

Socioeconomic deprivation and notification rates for tuberculosis in London during 1982-91

OBJECTIVES

To investigate the association between four sociodemographic measures (unemployment, overcrowding, low social class, and the proportion of migrants from areas of high prevalence of tuberculosis) and average level and rate of change of notification rates for tuberculosis.

DESIGN

Ecological analysis of both the average and the rate of change of standardised annual notification rates for tuberculosis from 1982-91 and sociodemographic measures from the 1981 and 1991 censuses.

SETTING

32 London boroughs. SUBJECTS AND DATA: Sociodemographic measures from the 1981 and 1991 censuses and tuberculosis notification rates for 1982-91.

MAIN OUTCOME MEASURES

A measure of the association between average levels and rate of change in tuberculosis notification rates and four sociodemographic measures in 1981 and between the rate of change in tuberculosis notification rates between 1981 and 1991 and changes in sociodemographic measures between 1981 and 1991.

RESULTS

The average level of notifications was correlated with overcrowding and the proportion of migrants but not with unemployment or social class. No significant association was found between the rate of change in notification rates and sociodemographic measures in 1981. An association was found between increases in unemployment and the rate of change in notification rates, but the effect was small. Changes in the levels of unemployment explained 23% of the variation between boroughs in the rate of change in their notification rates.

CONCLUSION

The average tuberculosis notification rates were related to overcrowding and the proportion of migrants in 1981. Only increases in unemployment from 1981 to 1991, however, were significantly associated with the rate of change in notifications over the same period.

Tuberculosis in England and Wales 1982-1993: notifications exceeded predictions

About 8000 more cases of tuberculosis were notified in the years 1988 to 1993 than would have been expected if previous trends had continued (95% confidence interval (CI) 3000-12,000). Tuberculosis notifications were analysed to determine the population groups and geographical areas in which increases occurred. Increases were greatest in regional health authorities (RHAs) with large conurbations, while rates generally continued to decline in RHAs that serve more rural areas. The rate of notification rose significantly in males aged 15 to 34 years and fell in men over 35. In females, the rate increased only in the 35 to 64 year age group. Non-respiratory tuberculosis accounted for 21% of notifications in 1987 and 27% in 1993. In most age, sex, and geographical groups significant increases were confined to non-respiratory tuberculosis, but the rate of both respiratory and non-respiratory tuberculosis rose in males aged 15 to 34 years in North Thames RHAs. A number of factors may have contributed to the observed increase. Reporting of cases may have improved following the appointment of consultants in communicable disease control in 1988, whose role includes improving notification practices. Such improvements might explain the increased proportion of notifications of non-respiratory tuberculosis, as this may have been undernotified to a greater extent than respiratory tuberculosis in the past. Other factors associated with recent increases are discussed.

Maternal factors and child's health care use

There is inadequate data about the association between specific psychosocial factors and pediatric health care use. We hypothesized that maternal substance abuse, depression, and low social support would be associated with increased medical visits, emergency room (ER) use, visits for injuries and delays in immunization. We conducted a prospective study of 202 U.S. families with preschool children in a clinic serving the inner city poor. Psychosocial factors were assessed from standardized screening questionnaires for substance abuse, depression and low social support. Research assistants blind to the study hypothesis reviewed medical records for health care over the year following completion of the questionnaire: number of clinic visits, use of emergency room, visits to the ER or clinic for injuries, and delays in immunizations of two months or more. Among the 202 mothers, the mean age was 24.4 years, 47% were African American, 32% Caucasian, and 14% Asian; 55% were high school graduates. The average household income was $7620 per year; the mean age of children was 12.2 months. Thirty-seven percent of mothers screened positively for substance abuse, 34% for depression, and 60% for low social support. Children had an average of 8.6 clinic visits per year; 41% had an ER visit, 21% had an injury resulting in an ER or clinic visit, and 43% of children under 2 years of age had a delay of 2 months or more in recommended immunizations. After controlling for maternal and child age in a regression equation, none of the psychosocial factors were significant predictors of health care use outcomes.(ABSTRACT TRUNCATED AT 250 WORDS)

Expression patterns of three genes in the stem of lucerne (Medicago sativa)

We have identified three stem abundantly expressed genes in lucerne (alfalfa, Medicago sativa). A cDNA library, constructed from lucerne stem polyadenylated RNA, was screened by differential hybridization. From this screening, cDNA clones that correspond to genes which are preferentially, or specifically, expressed in the stem were isolated. MsaS1 encodes an unidentified protein, MsaS2 encodes an S-adenosyl-homocysteine hydrolase and MsaS3 encodes an extensin-like protein. Northern blot analysis of RNA isolated from individual stem internodes indicated that the three corresponding genes show differing developmental patterns of expression. The expression of MsaS1 was confined to the youngest stem tissue and may be regulated by sucrose. In stem tissue the level of RNA for the three genes decreased in response to wounding. Tissue print hybridization analysis was used to localize the expression of the genes to the xylem side of vascular bundles in lucerne stems.

Determining Platypus Relationships

In the summer of 1990-91 the first captive breeding of platypus (Omithorhynchus anatinus) in 47 years, and only the second ever, occurred in a small resident population at Warrawong Sanctuary, South Australia. DNA fingerprinting and analyses employing the maternally inherited mitochondrial genome have been used to determine family relationships within this population Using hypervariable DNA sequences cloned from other species to probe blots of DNA from the Warrawong platypuses, individual-specific banding patterns have been observed that allow the identification of family relationships within the population. A novel method for detecting maternal relationships within platypus populations, based on polymerase chain reaction analyses of the highly polymorphic mitochondrial control region, is also presented.