Immune cell populations residing in mesenteric adipose depots and mesenteric lymph nodes of lean dairy cows.

Inconsistent evidence of inflammatory immune cell infiltrates in adipose tissues with extensive triglyceride mobilization raises the possibility that regulatory or anti-inflammatory immune cell populations reside within the mesenteric adipose tissue (MAT) and mesenteric lymph nodes (MLN). These resident immune cell populations may be involved in attenuating the inflammatory response. We explored the immune cell population of MAT and MLN collected from lean, lactating Holstein cows without apparent disease in an abattoir (n = 42). Lean cows had a body condition score of 2.6 ± 0.1 (mean ± SD) with a greater frequency of adipocyte area occurring in small rather than large adipocytes. Cells were labeled with monoclonal antibodies specific to bovine leukocyte antigens for enumeration by flow cytometry. Within both lymph node and adipose tissues, relatively large subpopulations of cells expressed the ß2 integrins CD11b and CD11c, class II major histocompatibility antigens (MHCII), and the SIIRP-1α receptor (CD172a) typical of dendritic cells and macrophages. Macrophage/dendritic cell heterogeneity was marked by ß2 integrin expression alone or in conjunction with CD172a or MHCII across subpopulations from both tissues; CD209, the DC-SIGN c-type lectin receptor of dendritic cells, was not detected by fluorescence-activated cell sorting in either tissue. Lymphocytes comprised 74.1 ± 3.7% and 13.7 ± 3.7% of the MLN and MAT cell populations, respectively, and CD3+CD4+ lymphocytes accounted for 49.8 ± 9.9% of the MLN and 6.13 ± 1.23% of the MAT cells. Fox P3+ regulatory lymphocytes comprised 15.3 ± 1.1% and 6.73 ± 0.52% of the MLN and MAT cells, whereas γδ+ lymphocytes accounted for 6.65 ± 0.74% and 3.91 ± 0.43% of the MLN and MAT cells, respectively. Subpopulations of CD3+CD8+ cytotoxic T cells and CD3+CD11c+ innate lymphocytes were present in MLN but not MAT. These results show that subpopulations of resident tissue macrophages, dendritic cells, T helper lymphocytes, regulatory T lymphocytes (Tregs), and γδ lymphocytes reside in mesenteric lymph nodes and adipose tissues. Balance in the innate and adaptive immune functions embedded in these tissues could support metabolic health.

Pilot randomised controlled trial of face-down positioning following macular hole surgery.

OBJECTIVE: This was a pilot randomised controlled trial (RCT) to investigate the effect of post-operative face-down positioning on the outcome of macular hole surgery and to inform the design of a larger definitive study. METHODS: In all, 30 phakic eyes of 30 subjects with idiopathic full-thickness macular holes underwent vitrectomy with dye-assisted peeling of the ILM and 14% perfluoropropane gas. Subjects were randomly allocated to posture face down for 10 days (posturing group) or to avoid a face-up position only (non-posturing group). The primary outcome was anatomical hole closure. RESULTS: Macular holes closed in 14 of 15 eyes (93.3%; 95% confidence interval (CI) 68-100%) in the posturing group and in 9 of 15 (60%; 95% CI 32-84%) in the non-posturing group. In a subgroup analysis of outcome according to macular hole size, all holes smaller than 400 µm closed regardless of posturing (100%). In contrast, holes larger than 400 µm closed in 10 of 11 eyes (91%; 95% CI 58-99%) in the posturing group and in only 4 of 10 eyes (40%; 95% CI 12-74%) in the non-posturing group (Fisher's exact test P=0.02). CONCLUSION: Post-operative face-down positioning may improve the likelihood of macular hole closure, particularly for holes larger than 400 µm. These results support the case for a RCT.

A new paradigm for international disease control: lessons learned from polio eradication in Southeast Asia.

OBJECTIVES: This study evaluated the impact of international coordination on polio eradication in Southeast Asia. METHODS: Active surveillance systems for acute flaccid paralysis were assessed. Analyses focused on surveillance proficiency and polio incidence. RESULTS: Ten countries coordinated activities. Importations occurred and were rapidly contained in China and Myanmar. Countries that have been free of indigenous polio transmission for at least 3 years include Sri Lanka, Indonesia, Myanmar, and Thailand. In the remaining endemic countries--India, Nepal, and Bangladesh--poliovirus transmission has been substantially reduced; however, these countries still harbor the world's largest polio reservoir. CONCLUSIONS: Unprecedented international coordination in Southeast Asia resulted in dramatic progress in polio eradication and serves as a paradigm for control of other infectious diseases such as malaria and tuberculosis.

When is a disease eradicable? 100 years of lessons learned.

Since the 1915 launch of the first international eradication initiative targeting a human pathogen, much has been learned about the determinants of eradicability of an organism. The authors outline the first 4 eradication efforts, summarizing the lessons learned in terms of the 3 types of criteria for disease eradication programs: (1) biological and technical feasibility, (2) costs and benefits, and (3) societal and political considerations.

Progress towards the eradication of poliomyelitis globally and in Africa, January 2000.

Led by an international partnership including Rotary International, the WHO, UNICEF and the Centers for Disease Control and Prevention in the USA, the global initiative to eradicate poliomyelitis has made remarkable progress since its beginning in 1988. The number of polio cases has decreased from an estimated 350,000 cases in 1988 to just over 5,000 reported cases in 1999. Following successful eradication from the WHO Region of the America's, certified as polio-free in 1994, wild poliovirus was last reported from the Western Pacific Region (including China) in 1997, and from the European Region (including all countries of the former Soviet Union) in November 1998. Large parts of Southern and Northern Africa and the Middle East are also polio-free. This success is related to the implementation of annual nationwide supplemental oral poliovaccine (OPV) campaigns in all recently or currently polio-endemic countries, targeting all children under 5 years with two doses of OPV. Progress of the initiative is monitored by special surveillance systems for all cases of acute flaccid paralysis (AFP) in children under 15 years, including virological testing to rule out wild poliovirus infection. The initiative currently focuses on a limited number of remaining endemic countries in South Asia and Africa, including India, Pakistan, Bangladesh, and Nigeria. The initiative is also beginning to be successful in several countries affected by conflict situations, such as Afghanistan, Sudan (South), Somalia, Democratic Republic of the Congo and Angola.

Disease eradication and health systems development.

This article provides a framework for the design of future eradication programmes so that the greatest benefit accrues to health systems development from the implementation of such programmes. The framework focuses on weak and fragile health systems and assumes that eradication leads to the cessation of the intervention required to eradicate the disease. Five major components of health systems are identified and key elements which are of particular relevance to eradication initiatives are defined. The dearth of documentation which can provide "lessons learned" in this area is illustrated with a brief review of the literature. Opportunities and threats, which can be addressed during the design of eradication programmes, are described and a number of recommendations are outlined. It is emphasized that this framework pertains to eradication programmes but may be useful in attempts to coordinate vertical and horizontal disease control activities for maximum mutual benefits.

Surgical removal of non-age-related subfoveal choroidal neovascular membranes.

PURPOSE: To assess anatomical and visual results following the surgical removal of non-age-related subfoveal choroidal neovascular membranes. METHODS: A retrospective study was carried out of 31 consecutive patients undergoing vitrectomy, parafoveal retinotomy and removal of subfoveal choroidal neovascular membranes that were either idiopathic or associated with multifocal choroiditis, high myopia, trauma or angioid streaks. RESULTS: Visual acuity improved or remained the same in 25 eyes (81%) after a mean follow-up of 10.1 months (range 3-37 months). visual acuity improved by more than 2 lines of Snellen acuity in 5 eyes (16%) and decreased by more than 2 lines in 2 eyes (6%). There was no significant association between the final visual outcome and length of symptoms prior to surgery or pre-operative visual acuity. Atrophy of the retinal pigment epithelium and older age were associated with poor outcome. Membranes recurred in 11 eyes (35%), and eyes with subfoveal blood prior to surgery were more likely to have recurrent membranes. CONCLUSIONS: The results of surgical removal of non-age-related subfoveal neovascular membranes have been encouraging, but further studies of long-term outcome and of the natural history of individual conditions are required.

Polio outbreak in Albania, 1996.

Between April and November 1996, a large outbreak of polio occurred in Albania, which had reported to be free of polio since 1985. Although Albania had not reported polio in that interval, the risk of introduction and circulation of wild poliovirus had in

Current status of the global eradication of poliomyelitis.

Substantial progress towards the global eradication of poliomyelitis by the year 2000 has been achieved since May 1988 when WHO Member States adopted this goal at the Forty-first World Health Assembly. Virtually all polio-endemic countries have begun to implement the WHO-recommended strategies to eradicate polio and it is expected that, by the end of 1997, all endemic countries in the world will have conducted full National Immunization Days (NID), providing supplemental oral polio vaccine (OPV) to nearly two-thirds of all children < 5 years. In contrast, although globally acute flaccid paralysis (AFP) surveillance was being conducted in 126 (86%) of 146 countries where polio is or recently was endemic, surveillance remains incomplete and untimely. A global network of polio laboratories, capable of detecting wild poliovirus when and where it occurs, has been developed. Furthermore, in countries where polio virus circulation has been limited to focal areas, and surveillance is adequate, mopping-up campaigns are being conducted to eliminate the final chains of transmission. The process for certification of polio eradication has been established in each WHO region as well as at the global level. The impact of the eradication initiative is evident, with an 88% decrease in the number of reported cases globally since 1988. In order to achieve the goal of eradication, the rapid development of complete and timely AFP surveillance and the continuation of effective NIDs constitute an urgent priority. This is of particular relevance in the remaining polio-endemic countries, especially in those that are affected by war or politically isolated and are important remaining reservoirs from where wild poliovirus continues to spread into bordering or even distant polio-free countries. External support will continue to be required by those countries and regions where the incidence of polio has reached low levels to ensure that final chains of poliovirus transmission are interrupted and to permit the eventual certification of eradication. The year 2000 objective for achieving poliomyelitis eradication remains a feasible target.

Breast implants, rheumatoid arthritis, and connective tissue diseases in a clinical practice.

This study was designed to assess the relationship between breast implants and certain rheumatologic diseases (rheumatoid arthritis and diffuse connective tissue diseases). The study base was a rheumatological practice in Atlanta, Georgia that started in 1982 and began computerizing its records in 1985. The computerized records through May 1992 included 4229 women patients, 150 with breast implants and 721 with a diagnosis of rheumatoid arthritis (RA) and/or one of the connective tissue diseases (CTDs). Of the 721 patients who had been diagnosed as having rheumatoid arthritis (RA) and/or one of the connective tissue diseases (CTDs), 392 had rheumatoid arthritis, 344 had connective tissue disease, 15 had both rheumatoid arthritis and a connective tissue disease, and 33 had more than one connective tissue disease. Of the patients with connective tissue disease, 179 had systemic lupus erythematosus, 64 had scleroderma, 49 had Sjögren's syndrome, 36 had dermatomyositis or polymyositis, and 49 had mixed connective tissue disease. Data were analyzed by univariate and multivariate techniques including logistic regression. Significant variables included age at first visit, income strata, and period of first visit. Analyses were performed for each clinical diagnosis, for all connective tissue diseases together (CTDs), and for those with rheumatoid arthritis and/or connective tissue disease (RA/CTD). Analyses were performed on the total data base and on the records of new patients (1986-1992). The adjusted odds ratio for breast implants among women who entered the practice in 1986-1992 and were diagnosed as having rheumatoid arthritis and/or one of the connective tissue diseases (RA/CTDs) was 0.45 (0.22-0.90), for those with rheumatoid arthritis was 0.61 (0.28-1.49), for those with any of these specific diffuse connective tissue diseases was 0.34 (0.11-1.06) compared to those without the disease. For systemic lupus erythematosus, the odds ratio of 0.24 (0.03-1.75) was based on a single case who had the disease 5 yr before the implant. For Sjögren's syndrome, the odds ratio was 1.67 (0.39-7.13) based on two cases, one of whom had the disease 5 yr before the implant. The calculated odds ratios for scleroderma, dermatomyositis/polymyositis, and mixed connective tissue disease were zero since no cases were diagnosed among the patients with breast implants. This study found no evidence that women with breast implants are at an increased risk for having rheumatoid arthritis or other diffuse connective tissue disease.

Model-based estimates of the risk of human immunodeficiency virus and hepatitis B virus transmission through unsafe injections.

BACKGROUND: Patient-to-patient transmission through contaminated medical equipment may be the principal route of nosocomial blood-borne infections globally. Quantifying cross infection risks could facilitate efforts to ensure safe injections in developing countries. METHOD: A mathematical model was developed to evaluate the risk of cross infection due to unsafe injections. The model was applied to immunization programmes with a fixed number of injections and in which unsterile needle and syringe reuse rates were specified. Risk estimates were generated using a range of human immunodeficiency virus (HIV) and hepatitis B (HBV) prevalences. RESULTS: The risk of cross infection is zero when properly sterilized equipment is used. With unsafe injections, the risk of cross infection with HBV is consistently higher than HIV for comparable levels of endemicity. A single reuse of each needle and syringe in areas with an HBeAg prevalence of 4% results in 980 cases of HBV/100,000 infants; reuse four times results in 3740 cases. When the HIV prevalence is 1% and the reuse rate is 4, 14 to 35 cases of HIV/100,000 women could occur. Contamination of multidose vaccine vials could considerably increase these estimates. CONCLUSIONS: Neither HIV nor HBV transmission has been reported with injections administered through the Expanded Programme on Immunization. However, ample evidence exists that reuse of unsterile needles and syringes is common in developing countries. Ongoing efforts to ensure safe practices and improve injection technologies are required to protect these populations from both medical and traditional skin-piercing procedures.

Reducing the risk of unsafe injections in immunization programmes: financial and operational implications of various injection technologies.

The unsafe use and disposal of injection equipment continues to put patients, health care workers, and the general community at risk of infections such as hepatitis B virus and human immunodeficiency virus. Although the potential for unsafe injection practices varies substantially with the type of equipment that is used, technology alone cannot totally eliminate the risk. A knowledge of the cost, practicality and, most importantly, the potential for misuse, is critical for selecting the most appropriate injection equipment for each immunization setting. Four types of injection equipment are currently available for administering vaccines: sterilizable needles and syringes; standard disposable needles and syringes; autodestruct needles and syringes; and jet injectors. In general, the cost per injection is lowest with sterilizable equipment and highest with autodestruct. However, only autodestruct syringes virtually eliminate the risk of unsafe injection practices. Owing to differences in cost and programme factors, in some settings it may be appropriate to use a combination of equipment. For example, autodestruct syringes may be used in areas where it is difficult to ensure adequate supervision, while in medium-sized, fixed-site clinics with safe injection practices, sterilizable equipment will be the most cost-effective.

PIP: Every year, more than 550 million injections are administered in developing countries through the Expanded Program on Immunization. It is imperative that great care be given to providing these immunizations with only sterile injection equipment. Otherwise, children may be subjected during immunization to infections such as hepatitis B virus and HIV. Sterilizable needles and syringes, standard disposable needles and syringes, autodestruct needles and syringes, and jet injectors are currently available for administering vaccines. The design and operation of the former two types of needles and syringes are, by definition, evident. The design of autodestruct needles and syringes and jet injectors, however, is less directly apparent from their nomenclature. Autodestruct syringes have a device in the barrel which prevents the plunger from being redrawn after a single use, thereby automatically blocking the syringe and preventing it from being reused. Jet injectors deliver immunizations with a high pressure jet of fluid generated by either a hydraulic or mechanical compression system. This equipment was developed for high workload use and has been employed in immunization campaigns for many years. Low workload injectors are being developed for use in the small immunization clinic setting. In general, the cost per injection is lowest with sterilizable equipment and highest with the autodestruct device. Only autodestruct syringes, however, virtually eliminate the risk of unsafe injection practices. It must be emphasized that technology alone cannot eliminate the risk of accidental infection using unsterile injection equipment. The authors note that it may be appropriate in some settings to use a combination of equipment. For example, autodestruct syringes may be used in areas where it is difficult to ensure adequate supervision, while in medium-sized, fixed-site clinics with safe injection practices, sterilizable equipment will be the most cost-effective.