The transfer and decay of maternal antibody against Shigella sonnei in a longitudinal cohort of Vietnamese infants.

BACKGROUND: Shigella sonnei is an emergent and major diarrheal pathogen for which there is currently no vaccine. We aimed to quantify duration of maternal antibody against S. sonnei and investigate transplacental IgG transfer in a birth cohort in southern Vietnam. METHODS AND RESULTS: Over 500-paired maternal/infant plasma samples were evaluated for presence of anti-S. sonnei-O IgG and IgM. Longitudinal plasma samples allowed for the estimation of the median half-life of maternal anti-S. sonnei-O IgG, which was 43 days (95% confidence interval: 41-45 days). Additionally, half of infants lacked a detectable titer by 19 weeks of age. Lower cord titers were associated with greater increases in S. sonnei IgG over the first year of life, and the incidence of S. sonnei seroconversion was estimated to be 4/100 infant years. Maternal IgG titer, the ratio of antibody transfer, the season of birth and gestational age were significantly associated with cord titer. CONCLUSIONS: Maternal anti-S. sonnei-O IgG is efficiently transferred across the placenta and anti-S. sonnei-O maternal IgG declines rapidly after birth and is undetectable after 5 months in the majority of children. Preterm neonates and children born to mothers with low IgG titers have lower cord titers and therefore may be at greater risk of seroconversion in infancy

An Update on Anti-CD137 Antibodies in Immunotherapies for Cancer

The selective expression of CD137 on cells of the immune system (e.g., T and DC cells) and oncogenic cells in several types of cancer leads this molecule to be an attractive target to discover cancer immunotherapy. Therefore, specific antibodies against CD137 are being studied and developed aiming to activate and enhance anti-cancer immune responses as well as suppress oncogenic cells. Accumulating evidence suggests that anti-CD137 antibodies can be used separately to prevent tumor in some cases, while in other cases, these antibodies need to be co-administered with other antibodies or drugs/vaccines/regents for a better performance. Thus, in this work, we aim to update and discuss current knowledge about anti-cancer effects of anti-CD137 antibodies as mono- and combined-immunotherapies

The Potential of Medical Abortion to Reduce Maternal Mortality in Africa: What Benefits for Tanzania and Ethiopia?

BACKGROUND: Unsafe abortion is estimated to account for 13% of maternal mortality globally. Medical abortion is a safe alternative. METHODS: By estimating mortality risks for unsafe and medical abortion and childbirth for Tanzania and Ethiopia, we modelled changes in maternal mortality that are achievable if unsafe abortion were replaced by medical abortion. We selected Ethiopia and Tanzania because of their high maternal mortality ratios (MMRatios) and contrasting situations regarding health care provision and abortion legislation. We focused on misoprostol-only regimens due to the drug's low cost and accessibility. We included the impact of medical abortion on women who would otherwise choose unsafe abortion and on women with unwanted/mistimed pregnancies who would otherwise carry to term. RESULTS: Thousands of lives could be saved each year in each country by implementing medical abortion using misoprostol (2122 in Tanzania and 2551 in Ethiopia assuming coverage equals family planning services levels: 56% for Tanzania, 31% for Ethiopia). Changes in MMRatios would be less pronounced because the intervention would also affect national birth rates. CONCLUSIONS: This is the first analysis of impact of medical abortion provision which takes into account additional potential users other than those currently using unsafe abortion. Thousands of women's lives could be saved, but this may not be reflected in as substantial changes in MMRatios because of medical abortion's demographic impact. Therefore policy makers must be aware of the inability of some traditional measures of maternal mortality to detect the real benefits offered by such an intervention

Analysis of Delay-Aware Worm Propagation Model in Wireless IoT Systems With Ratio-Dependent Functional Response

This article presents a delayed susceptibility, exposure, infectivity, recovery, and vaccination (SEIRV) model with nonlinear incidence and ratio-dependent functional responses. Model limitations and local stability analyses were examined with strict consideration of delay awareness. In addition, the presence of Hopf bifurcations with delay as a bifurcation parameter was investigated along with feature distributions with appropriate constraints. Numerical simulations are presented to verify the proposed theoretical results. In particular, if the latency exceeds the threshold, worm propagation in the system may become out of control. We demonstrated that the propagation characteristics of worms can easily be predicted and eliminated if the delay values are below a suitable threshold. Finally, we conclude that worm propagation is controllable by shifting the presence of Hopf bifurcations

Molecular targeting of antiangiogenic factor 16K hPRL inhibits oxygen-induced retinopathy in mice

PURPOSE. To examine the ability and mechanism of the 16 kDa N-terminal fragment of human prolactin (16K hPRL) in the inhibition of abnormal retinal neovascularization. METHODS. The 16K hPRL-encoding sequence was inserted into an adenoviral vector (16K-Ad). Western blot analysis verified the expression of 16K hPRL and inhibition of proliferation, confirming functional activity of the 16K hPRL in virus-infected adult bovine aortic endothelial (ABAE) cells. 16K hPRL inhibited retinal neovascularization in a mouse model of oxygen-induced retinopathy. The ability of recombinant 16K hPRL expressed in E. coli (r16K hPRL) was compared to that of endostatin in inducing apoptosis of cultured human retinal endothelial cells (HREC). RESULTS. 16K was expressed in virus-infected ABAE cells and resulted in a dose-dependent inhibition of cell proliferation. Eyes injected with 16K-Ad showed a reduction in preretinal neovascularization of 82.3 +/- 9.3% (P < 0.00001) when compared to uninjected controls. r16K hPRL was 100 times more potent than endostatin in inducing apoptosis in HRECs. CONCLUSIONS. Intravitreal administration of 16K hPRL inhibited neovascularization in the mouse model of oxygen-induced retinopathy. 16K hPRL stimulated apoptosis in HRECs and inhibited cell proliferation in ABAE cells. These results suggested a potential therapeutic role for 16K hPRL in the treatment of proliferative retinopathies

The value of daily platelet counts for predicting dengue shock syndrome: Results from a prospective observational study of 2301 Vietnamese children with dengue.

Background Dengue is the most important mosquito-borne viral infection to affect humans. Although it usually manifests as a self-limited febrile illness, complications may occur as the fever subsides. A systemic vascular leak syndrome that sometimes progresses to life-threatening hypovolaemic shock is the most serious complication seen in children, typically accompanied by haemoconcentration and thrombocytopenia. Robust evidence on risk factors, especially features present early in the illness course, for progression to dengue shock syndrome (DSS) is lacking. Moreover, the potential value of incorporating serial haematocrit and platelet measurements in prediction models has never been assessed. Methodology/Principal findings We analyzed data from a prospective observational study of Vietnamese children aged 5±15 years admitted with clinically suspected dengue to the Hospital for Tropical Diseases in Ho Chi Minh City between 2001 and 2009. The analysis population comprised all children with laboratory-confirmed dengue enrolled between days 1±4 of illness. Logistic regression was the main statistical model for all univariate and multivariable analyses. The prognostic value of daily haematocrit levels and platelet counts were assessed using graphs and separate regression models fitted on each day of illness. Among the 2301 children included in the analysis, 143 (6%) progressed to DSS. Significant baseline risk factors for DSS included a history of vomiting, higher temperature, a palpable liver, and a lower platelet count. Prediction models that included serial daily platelet counts demonstrated better ability to discriminate patients who developed DSS from others, than models based on enrolment information only. However inclusion of daily haematocrit values did not improve prediction of DSS. Conclusions/Significance Daily monitoring of platelet counts is important to help identify patients at high risk of DSS. Development of dynamic prediction models that incorporate signs, symptoms, and daily laboratory measurements, could improve DSS prediction and thereby reduce the burden on health services in endemic areas.</p