Therapeutic Treg expansion in mice by TNFRSF25 prevents allergic lung inflammation

TNF receptor superfamily member 25 (TNFRSF25; also known as DR3, and referred to herein as TNFR25) is constitutively and highly expressed by CD4(+)FoxP3(+) Tregs. However, its function on these cells has not been determined. Here we used a TNFR25-specific agonistic monoclonal antibody, 4C12, to study the effects of TNFR25 signaling on Tregs in vivo in mice. Signaling through TNFR25 induced rapid and selective expansion of preexisting Tregs in vivo such that they became 30%-35% of all CD4(+) T cells in the peripheral blood within 4 days. TNFR25-induced Treg proliferation was dependent upon TCR engagement with MHC class II, IL-2 receptor, and Akt signaling, but not upon costimulation by CD80 or CD86; it was unaffected by rapamycin. TNFR25-expanded Tregs remained highly suppressive ex vivo, and Tregs expanded by TNFR25 in vivo were protective against allergic lung inflammation, a mouse model for asthma, by reversing the ratio of effector T cells to Tregs in the lung, suppressing IL-13 and Th2 cytokine production, and blocking eosinophil exudation into bronchoalveolar fluid. Our studies define what we believe to be a novel mechanism for Treg control and important functions for TNFR25 in regulating autoaggression that balance its known role in enhancing autoimmunity.

Estimating maternal mortality in rural areas of Mexico: the application of an indirect demographic method

OBJECTIVE

To measure maternal mortality levels in rural areas of Mexico.

METHODS

In a cross-sectional study, a census of 13,378 households was carried out in the municipalities of Yecapixtla and Tlaltizapan, Morelos, Mexico. Information on 10,443 subjects from 12 to 49 years old was included in the analysis. An indirect method of measuring maternal mortality--the sisterhood method--was used to estimate maternal mortality. Information about the number of sisters of the interviewees who died due to maternal causes was collected in the census. With this information, estimates of maternal mortality related to a period of 10-12 years before the application of the census were obtained. An innovation to the original method was the calculation of a confidence interval for the estimated maternal mortality rate (MMR).

RESULTS

The MMR in this region was 18.68/10,000 live births (95% CI 15.79-21.58/10,000 live births). The average risk of dying due to maternal causes was 1 in 87 for women between 12 and 49 years of age.

CONCLUSIONS

The sisterhood method was effective for estimating maternal mortality in a small region, with no previous information about this indicator. The method proved to be useful for identifying a priority region for the implementation of maternal mortality reduction programs. Furthermore, the method was particularly convenient since it was applied as part of a multipurpose survey.

[The factors associated with hospital maternal death in the state of Morelos, Mexico]

The objective of this case-control study was to assess some risk factors related to hospital maternal mortality in the state of Morelos, Mexico. The cases were all maternal deaths which occurred in Morelos between 1989 and 1991 (n = 35), and the controls were women who presented the same complications and were taken care for at the same hospitals than the cases, but survived pregnancy and delivery (n = 35). The results showed that living with a partner is a protective factor (OR = 0.08), as well as using family planning methods (OR = 0.15). Not receiving care at the first place where it was requested was a risk factor (OR = 6.6). Maternal deaths had the same number of prenatal care visits than controls, but their first visit occurred, in average, one month later. The implications of the small sample size, characteristic of the studies on maternal mortality, are discussed at length. The results pinpoint the need to strengthen high-risk pregnancies screening programs through early prenatal care, and promote intersectorial strategies to provide care to pregnant women.

Furazolidone and chloramphenicol for treatment of typhoid fever

Seventy-one adults who were hospitalized between March 1985 and March 1987 were entered into a randomized, double-blind study to compare the efficacy and safety of furazolidone and chloramphenicol in therapy for typhoid fever. Patients received chloramphenicol capsules (total daily dosage, 2 g) plus placebo tablets for furazolidone tablets (total daily dosage, 800 mg) plus placebo capsules for 14 days. Seven patients were excluded from the analysis of efficacy because blood, bile, or bone marrow cultures at admission failed to demonstrate the presence of Salmonella typhi. Four additional patients were excluded because of intercurrent illness or failure to return for follow-up visits. Cure was achieved in 31 (97%) of 32 chloramphenicol recipients and 24 (86%) of 28 furazolidone recipients. In the chloramphenicol group, one patient experienced moderate sideroblastic anemia, and another experienced moderate neutropenia. Both adverse reactions resolved spontaneously within 7 days. Mild gastritis was reported by two patients who received furazolidone and one who received chloramphenicol. This study has demonstrated that furazolidone is an effective and safe alternative to chloramphenicol for the treatment of typhoid fever in adults.