G-CSF administration is neuroprotective following transient cerebral ischemia even in the absence of a functional NOS-2 gene

Granulocyte colony-stimulating factor (G-CSF) is a candidate neuroprotective factor following cerebral ischemia. To determine whether G-CSF acts partly through the inhibition of nitric oxide synthase (NOS)-2 expression, we administered G-CSF to male NOS-2−/− mice after cerebral ischemia. Although male NOS-2−/− mice exhibit resistance to the gross effects of cerebral ischemia, they display neuronal loss and skilled motor deficits following cerebral ischemia. Administration of G-CSF during reperfusion reduced motor deficit and neuronal loss. Thus, G-CSF is still effective in NOS-2 gene-deficient mice, suggesting that part of the mechanism of action is independent of NOS-2.     

Triple antiplatelet therapy for preventing vascular events: a systematic review and meta-analysis

Background  

Dual antiplatelet therapy is usually superior to mono therapy in preventing recurrent vascular events (VEs). This systematic review assesses the safety and efficacy of triple antiplatelet therapy in comparison with dual therapy in reducing recurrent vascular events.     

Prevalence of tuberculous infection and incidence of tuberculosis: a re-assessment of the Styblo rule

OBJECTIVE: To evaluate the validity of the fixed mathematical relationship between the annual risk of tuberculous infection (ARTI), the prevalence of smear-positive tuberculosis (TB) and the incidence of smear-positive TB specified as the Styblo rule, which TB control programmes use to estimate the incidence of TB disease at a population level and the case detection rate. METHODS: Population-based tuberculin surveys and surveys on prevalence of smear-positive TB since 1975 were identified through a literature search. For these surveys, the ratio between the number of tuberculous infections (based on ARTI estimates) and the number of smear-positive TB cases was calculated and compared to the ratio of 8 to 12 tuberculous infections per prevalent smear- positive TB case as part of the Styblo rule. FINDINGS: Three countries had national population-based data on both ARTI and prevalence of smear-positive TB for more than one point in time. In China the ratio ranged from 3.4 to 5.8, in the Philippines from 2.6 to 4.4, and in the Republic of Korea, from 3.2 to 4.7. All ratios were markedly lower than the ratio that is part of the Styblo rule. CONCLUSION: According to recent country data, there are typically fewer than 8 to 12 tuberculous infections per prevalent smear-positive TB case, and it remains unclear whether this ratio varies significantly among countries. The decrease in the ratio compared to the Styblo rule probably relates to improvements in the prompt treatment of TB disease (by national TB programmes). A change in the number of tuberculous infections per prevalent smear-positive TB case in population-based surveys makes the assumed fixed mathematical relationship between ARTI and incidence of smear-positive TB no longer valid.     

Tuberculosis Acquired Outside of Households, Rural Vietnam

Using population-based data from rural Vietnam, we assessed tuberculosis (TB) transmission within and outside of households. Eighty-three percent of persons with recent household TB were infected by different strains of Mycobacterium tuberculosis than were their household members. This result argues against the effectiveness of active TB case finding among household members.     

Limited impact of tuberculosis control in Hong Kong: attributable to high risks of reactivation disease

Over 50% of the global burden of tuberculosis occurs in South East Asia and the Western Pacific. Since 1950, notification rates in high-income countries in these settings have declined slowly and have remained over ten-fold greater than those in Western populations. The reasons for the slow decline are poorly understood. Using an age-structured model describing the incidence of Mycobacterium tuberculosis infection and disease applied to notification data from Hong Kong, we illustrate that in Hong Kong, a high prevalence of M. tuberculosis infection among older individuals and a high risk of disease through reactivation (e.g. up to 17-fold greater than that estimated for infected males in the United Kingdom) may explain this slow decline. If this feature of the epidemiology of tuberculosis is widespread, the WHO directly observed treatment short-course (DOTS) strategy may have a smaller impact in Asia in the short term than has been implied by recent predictions, all of which have been based on disease risk estimates derived from Western Europe. As a result, it may be difficult to meet the targets for tuberculosis control, which have been prescribed by the UN Millennium Development Goals.     

A population-based study of syphilis and sexually transmitted disease syndromes in north-western Tanzania. 2. Risk factors and health seeking behaviour.

OBJECTIVE--To determine risk factors for syphilis and sexually transmitted disease (STD) syndromes, and to study health seeking behaviour among those with STD syndromes, in the population of Mwanza Region, North-Western Tanzania. METHODS--A population-based random cluster sample survey, stratified by rural, roadside or urban residence, of 4173 individuals aged 15-54 years was performed in 1990-91. The seroprevalence of syphilis and the prevalence and incidence of self-reported genital ulcer syndrome (GUS) and genital discharge syndrome (GDS) are reported in the accompanying paper. This paper reports on risk factors for these conditions and on health seeking behaviour among those reporting them. RESULTS--In both sexes, the risk of STDs increased with the reported number of sexual partners in the previous five years. Men who were separated, divorced or widowed were at increased risk of STDs, but this was not the case among women. Higher educational status was associated with an increased risk of urethral discharge in males but with a decreased prevalence of syphilis in females. Male circumcision was associated with an increased risk of urethral discharge but a reduced prevalence of syphilis. Nearly all men, and 90% of women, reporting symptoms of genital discharge or ulceration had sought treatment. Of these, approximately 70% of males and 60% of females had sought treatment in the official health sector. CONCLUSIONS--Targetted health education concerning risk reduction for HIV infection and other STDs should be a high priority in this population. Improved case management of STDs in health centres and dispensaries may have a substantial impact on the incidence of these infections.     

Tetralogy of Fallot: MR findings

Surgical treatment of patients with tetralogy of Fallot requires accurate definition of all anatomic structures, particularly the central pulmonary arteries. Magnetic resonance (MR) images of 22 patients with tetralogy of Fallot were studied to assess their usefulness in providing information regarding the spectrum of anatomic abnormalities in this condition. MR findings were compared with information obtained at catheterization (in 16 patients) and at surgery (in nine patients), both of which were performed within 3 months of MR imaging. Ventricular chamber enlargement and wall hypertrophy were clearly delineated in most of the 17 patients who were examined before definitive surgical repair, and ventricular septal defects were visualized in all 17. Palliative systemic-to-pulmonary shunts were visualized in 11 patients and could be evaluated for patency. Most important, the morphology and size of the right ventricular outflow tract and central pulmonary arteries could be accurately assessed. Pulmonary artery measurements obtained from MR images demonstrated excellent correlation with angiographic measurements. In six patients examined after complete surgical repair, MR images accurately reflected changes in pulmonary artery outflow tract morphology and complications, such as residual pulmonary artery stenosis and thrombosis. The findings suggest that MR imaging can complement or obviate catheterization in the evaluation of tetralogy of Fallot with regard to suitability for definitive surgical repair.