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Indian Journal of Pediatrics -  相似文献   
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The efforts for the development and testing of vaccines against Trypanosoma cruzi infection have increased during the past years. We have designed a TcVac series of vaccines composed of T. cruzi derived, GPI-anchored membrane antigens. The TcVac vaccines have been shown to elicit humoral and cellular mediated immune responses and provide significant (but not complete) control of experimental infection in mice and dogs. Herein, we aimed to test two immunization protocols for the delivery of DNA-prime/DNA-boost vaccine (TcVac1) composed of TcG2 and TcG4 antigens in a BALB/c mouse model. Mice were immunized with TcVac1 through intradermal/electroporation (IDE) or intramuscular (IM) routes, challenged with T. cruzi, and evaluated during acute phase of infection. The humoral immune response was evaluated through the assessment of anti-TcG2 and anti-TcG4 IgG subtypes by using an ELISA. Cellular immune response was assessed through a lymphocyte proliferation assay. Finally, clinical and morphopathological aspects were evaluated for all experimental animals. Our results demonstrated that when comparing TcVac1 IDE delivery vs IM delivery, the former induced significantly higher level of antigen-specific antibody response (IgG2a?+?IgG2b?>?IgG1) and lymphocyte proliferation, which expanded in response to challenge infection. Histological evaluation after challenge infection showed infiltration of inflammatory cells (macrophages and lymphocytes) in the heart and skeletal tissue of all infected mice. However, the largest increase in inflammatory infiltrate was observed in TcVac1_IDE/Tc mice when compared with TcVac1_IM/Tc or non-vaccinated/infected mice. The extent of tissue inflammatory infiltrate was directly associated with the control of tissue amastigote nests in vaccinated/infected (vs. non-vaccinated/infected) mice. Our results suggest that IDE delivery improves the protective efficacy of TcVac1 vaccine against T. cruzi infection in mice when compared with IM delivery of the vaccine.  相似文献   
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Background

The resuscitation and critical care unit is a novel emergency department–intensive care unit designed to provide early critical care to emergency department patients for ≤24 h.

Objectives

This study sought to identify clinical variables associated with short intensive care unit (ICU) stays in patients with diabetic ketoacidosis (DKA), who commonly require ICU-level care.

Methods

We conducted a retrospective, single-center, cross-sectional study of DKA patients ≥18 years of age who presented to an academic, urban hospital emergency department over 16 months. Patient demographics and clinical variables extracted from medical records were compared between prolonged ICU stay patients of ≥24 h versus short ICU stay patients (SSPs) of <24 h. ICU care was defined as treatment in the resuscitation and critical care unit or inpatient ICU.

Results

One hundred sixty-eight emergency department visits with a primary diagnosis of DKA were analyzed. There were 53 prolonged ICU stay patients, 58 SSPs, and 57 patients required no ICU time. SSPs had significantly higher initial serum bicarbonate (13.0 vs. 9.0 mEq/L, p = 0.01) and shorter anion gap closure time (9.8 vs. 14.4 hours, p = 0.003). Medication nonadherence was a significantly more frequent precipitant in SSPs (67.2% vs. 47.2%, p = 0.03). Initial anion gap, glucose, beta-hydroxybutyrate, and severity of illness scores were not significantly different between groups. After multivariate logistic regression adjusting for variables significant from univariate analysis, higher initial bicarbonate (p = 0.04) and medication nonadherence (p = 0.03) remained significantly associated with SSPs.

Conclusions

Patients with DKA with short ICU stays have higher initial bicarbonate levels and are more likely to have medication nonadherence than patients requiring prolonged critical care. These variables may identify patients with DKA who are best treated in an emergency department–intensive care unit to potentially reduce inpatient ICU use.  相似文献   
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Approximately, 30 000 men die from prostate cancer (PCa) every year in the United States, mainly due to the metastasis. Thus, the key events associated with PCa metastasis are under rigorous investigation, with recent studies showing that preparation of pre-metastatic niches (PMN) in distant organs is an important step. However, the molecular basis for PMN preparation is still unclear. Hypoxia in primary tumors promotes aggressiveness; however, its precise role in metastasis is not clear. We recently reported that exosomes secreted by PCa cells under hypoxia promote stemness and invasiveness in naïve PCa cells; however, whether these extracellular vesicles also influence PMN remains unknown. In the present study, we isolated exosomes from human PCa PC3 cells under normoxic (21% O2, exosomes secreted under normoxic condition [ExoNormoxic]) and hypoxic (1% O2, exosomes secreted under hypoxic condition [ExoHypoxic]) conditions, and characterized their effect (10 µg exosomes, intraperitoneal (IP) treatment every 48 hours for 4 weeks) on key biomarkers associated with PMN in nude mice. Whole animal fluorescence imaging showed that ExoHypoxic treatment promotes matrix metalloproteinases (MMPs) activity in several putative metastatic sites. Histological studies confirmed that ExoHypoxic treatment enhanced the level of MMP2, MMP9, and extracellular matrix proteins (fibronectin and collagen) as well as increased the number of CD11b+ cells at selective PMN sites. Furthermore, proteomic profiling of exosomes by liquid chromatography/mass spectrometry identified cargo proteins in ExoNormoxic and ExoHypoxic as well as distinct canonical pathways targeted by them. These results suggest that exosomes secreted by PCa cells under hypoxia plausibly remodel distant PMN, and thus, could be a potential target to control metastatic PCa.  相似文献   
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Objectives

To find out the relative prevalence of fetal neural tube defect (NTD) and its outcome in terms of survival at birth and beyond 2 years of age.

Methods

A 10-year prospective (2008–2018) observational study was performed, which included all prenatally detected fetal NTD. Two-year follow-up was done in cases of pregnancies resulting in live birth, in terms of their survival, physical morbidity and developmental delay.

Results

NTD was seen in 401/648 (62%) cases among the central nervous system malformations. More than half of the cases (54.1%) presented after 20 weeks of gestation, and 42.8% of the mothers were primiparous. Spina bifida was seen in 206 cases, anencephaly in 144, encephalocele in 43, whereas iniencephaly was seen in only eight cases. Associated anomalies were present in 51.2%. Only 19.0% cases were live-born, and merely 11% were alive beyond 2 years of age. Among types of spina bifida, lumbosacral meningomyocele was the most common (41.6%), whereas thoracic was the rarest (8.7%). After 2 years, physical disability was observed in more than half of the cases who survived.

Conclusions

NTD is one of the commonest malformations with high mortality, and the physical and mental sub-normality is high among those who survive.

  相似文献   
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