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1.
Haptoglobin’s (Hp) antioxidant and pro-angiogenic properties differ between the 1-1, 2-1, and 2-2 phenotypes. Hp phenotype affects cardiovascular disease risk and treatment response to antioxidant vitamins in some non-pregnant populations. We previously demonstrated that preeclampsia risk was doubled in white Hp 2-1 women, compared to Hp 1-1 women. Our objectives were to determine whether we could reproduce this finding in a larger cohort, and to determine whether Hp phenotype influences lack of efficacy of antioxidant vitamins in preventing preeclampsia and serious complications of pregnancy-associated hypertension (PAH). This is a secondary analysis of a randomized controlled trial in which 10,154 low-risk women received daily vitamin C and E, or placebo, from 9-16 weeks gestation until delivery. Hp phenotype was determined in the study prediction cohort (n = 2,393) and a case-control cohort (703 cases, 1,406 controls). The primary outcome was severe PAH, or mild or severe PAH with elevated liver enzymes, elevated serum creatinine, thrombocytopenia, eclampsia, fetal growth restriction, medically indicated preterm birth or perinatal death. Preeclampsia was a secondary outcome. Odds ratios were estimated by logistic regression. Sampling weights were used to reduce bias from an overrepresentation of women with preeclampsia or the primary outcome. There was no relationship between Hp phenotype and the primary outcome or preeclampsia in Hispanic, white/other or black women. Vitamin supplementation did not reduce the risk of the primary outcome or preeclampsia in women of any phenotype. Supplementation increased preeclampsia risk (odds ratio 3.30; 95% confidence interval 1.61–6.82, p<0.01) in Hispanic Hp 2-2 women. Hp phenotype does not influence preeclampsia risk, or identify a subset of women who may benefit from vitamin C and E supplementation to prevent preeclampsia.  相似文献   

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3.
Gene transfer to T lymphocytes has historically relied on retro and lentivirus, but recently transposon-based gene transfer is rising as a simpler and straight forward approach to achieve stable transgene expression. Transfer of expression cassettes to T lymphocytes remains challenging, being based mainly on commercial kits.

Aims

We herein report a convenient and affordable method based on in house made buffers, generic cuvettes and utilization of the widely available Lonza nucleofector II device to promote efficient gene transfer to T lymphocytes.

Results

This approach renders high transgene expression levels in primary human T lymphocytes (mean 45%, 41–59%), the hard to transfect murine T cells (mean 38%, 36–42% for C57/BL6 strain) and human Jurkat T cell line. Cell viability levels after electroporation allowed further manipulations such as in vitro expansion and Chimeric Antigen Receptor (CAR) mediated gain of function for target cell lysis.

Conclusions

We describe here an efficient general protocol for electroporation based modification of T lymphocytes. By opening access to this protocol, we expect that efficient gene transfer to T lymphocytes, for transient or stable expression, may be achieved by an increased number of laboratories at lower and affordable costs.  相似文献   

4.

Background

Women with preeclampsia (PEC) and gestational hypertension (GH) exhibit insulin resistance during pregnancy, independent of obesity and glucose intolerance. Our aim was to determine whether women with PEC or GH during pregnancy have an increased risk of developing diabetes after pregnancy, and whether the presence of PEC/GH in addition to gestational diabetes (GDM) increases the risk of future (postpartum) diabetes.

Methods and Findings

We performed a population-based, retrospective cohort study for 1,010,068 pregnant women who delivered in Ontario, Canada between April 1994 and March 2008. Women were categorized as having PEC alone (n = 22,933), GH alone (n = 27,605), GDM alone (n = 30,852), GDM+PEC (n = 1,476), GDM+GH (n = 2,100), or none of these conditions (n = 925,102). Our main outcome was a new diagnosis of diabetes postpartum in the following years, up until March 2011, based on new records in the Ontario Diabetes Database. The incidence rate of diabetes per 1,000 person-years was 6.47 for women with PEC and 5.26 for GH compared with 2.81 in women with neither of these conditions. In the multivariable analysis, both PEC alone (hazard ratio [HR] = 2.08; 95% CI 1.97–2.19) and GH alone (HR = 1.95; 95% CI 1.83–2.07) were risk factors for subsequent diabetes. Women with GDM alone were at elevated risk of developing diabetes postpartum (HR = 12.77; 95% CI 12.44–13.10); however, the co–presence of PEC or GH in addition to GDM further elevated this risk (HR = 15.75; 95% CI 14.52–17.07, and HR = 18.49; 95% CI 17.12–19.96, respectively). Data on obesity were not available.

Conclusions

Women with PEC/GH have a 2-fold increased risk of developing diabetes when followed up to 16.5 years after pregnancy, even in the absence of GDM. The presence of PEC/GH in the setting of GDM also raised the risk of diabetes significantly beyond that seen with GDM alone. A history of PEC/GH during pregnancy should alert clinicians to the need for preventative counseling and more vigilant screening for diabetes. Please see later in the article for the Editors'' Summary  相似文献   

5.

Background

Depression is a common disorder affecting 10–15% women in the postpartum period. Postpartum depression can disrupt early mother-infant interaction, and constitutes a risk factor for early child development. Recently, attention has been drawn to the hypothesis that a low intake of seafood in pregnancy can be a risk factor for postpartum depression. Seafood is a unique dietary source of the marine omega-3 fatty acids and is a natural part of a healthy balanced diet that is especially important during pregnancy.

Methods

In a community based prospective cohort in a municipality in Western Norway, we investigated both nutritional and psychological risk factors for postpartum depression. The source population was all women who were pregnant within the period November 2009 - June 2011. The fatty acid status in red blood cells was assessed in the 28th gestation week and participants were screened for postpartum depression using the Edinburgh Postnatal Depression Scale (EPDS) three months after delivery. The aim of the present study was to investigate if a low omega-3 index in pregnancy is a possible risk factor for postpartum depression.

Results

In a simple regression model, the omega-3 index was associated with the EPDS score in a nonlinear inverse manner with an R square of 19. Thus, the low omega-3 index explained 19% of the variance in the EPDS score. The DPA content, DHA content, omega-3 index, omega-3/omega-6 ratio, total HUFA score, and the omega-3 HUFA score were all inversely correlated with the EPDS score. The EPDS scores of participants in the lowest omega-3 index quartile were significantly different to the three other omega-3 index quartiles.

Conclusion

In this study population, a low omega-3 index in late pregnancy was associated with higher depression score three months postpartum.  相似文献   

6.

Background

Oxidative stress in preeclampsia and small for gestational age (SGA) birth suggests antioxidant supplementation could prevent these conditions. However, it remains unclear whether maternal antioxidant levels are systematically lower in these pregnancies.

Objective

To conduct a systematic review of the association between maternal antioxidant levels during pregnancy and preeclampsia or SGA.

Methods

We searched PubMed, Embase, and several other databases from 1970–2013 for observational studies that measured maternal blood levels of non-enzymatic antioxidants (vitamins A, C, E, and carotenoids) during pregnancy or within 72 hours of delivery. The entire review process was done in duplicate. Study quality was assessed using the Newcastle-Ottawa Scale and additional questions. We pooled the standardized mean difference (SMD) across studies, stratified by outcome and pregnancy trimester, and investigated heterogeneity using meta-regression.

Results

We reviewed 1,882 unique citations and 64 studies were included. Most studies were small with important risk of bias. Among studies that addressed preeclampsia (n = 58) and SGA (n = 9), 16% and 66%, respectively, measured levels prior to diagnosis. The SMDs for vitamins A, C, and E were significantly negative for overall preeclampsia, but not for mild or severe preeclampsia subtypes. Significant heterogeneity was observed in all meta-analyses and most could not be explained. Evidence for lower carotenoid antioxidants in preeclampsia and SGA was limited and inconclusive. Publication bias appears likely.

Conclusions

Small, low-quality studies limit conclusions that can be drawn from the available literature. Observational studies inconsistently show that vitamins C and E or other antioxidants are lower in women who develop preeclampsia or SGA. Reverse causality remains a possible explanation for associations observed. New clinical trials are not warranted in light of this evidence; however, additional rigorous observational studies measuring antioxidant levels before clinical detection of preeclampsia and SGA may clarify whether levels are altered at a causally-relevant time of pregnancy.  相似文献   

7.
Summary .  The initial detection of ventilator-associated pneumonia (VAP) for inpatients at an intensive care unit needs composite symptom evaluation using clinical criteria such as the clinical pulmonary infection score (CPIS). When CPIS is above a threshold value, bronchoalveolar lavage (BAL) is performed to confirm the diagnosis by counting actual bacterial pathogens. Thus, CPIS and BAL results are closely related and both are important indicators of pneumonia whereas BAL data are incomplete. To compare the pneumonia risks among treatment groups for such incomplete data, we derive a method that combines nonparametric empirical likelihood ratio techniques with classical testing for parametric models. This technique augments the study power by enabling us to use any observed data. The asymptotic property of the proposed method is investigated theoretically. Monte Carlo simulations confirm both the asymptotic results and good power properties of the proposed method. The method is applied to the actual data obtained in clinical practice settings and compares VAP risks among treatment groups.  相似文献   

8.
With the widespread use of quantum dots (QDs), the likelihood of exposure to quantum dots has increased substantially. The application of quantum dots in numerous biomedical areas requires detailed studies on their toxicity. In this study, we aimed to determine the threshold dose which reduced or eliminated CdTe-induced toxicity in L929 cells by controlling the exposure dose. We established a cellular model of acute exposure to CdTe QDs. Cells were exposed to different concentrations of CdTe QDs (2.2 nm and 3.5 nm) followed by illustrative cytotoxicity analysis. The results showed that low concentrations of CdTe QDs (under 10 µg/mL) promoted cell viability, caused no obvious effect on the rate of cell apoptosis, intracellular calcium levels and changes in mitochondrial membrane potential, while high concentrations significantly inhibited cell viability. In addition, reactive oxygen species in the 10 µg/mL-treated group was significantly reduced compared with the control group. In summary, the cytotoxicity of CdTe QDs on L929 cell is dose-dependent, time-dependent and size-dependent. Low concentrations of CdTe QDs (below 10 µg/mL) may be nontoxic and safe in L929 cells, whereas high concentrations (above 10 µg/mL) may be toxic resulting in inhibition of proliferation and induction of apoptosis in L929 cells.  相似文献   

9.
Substantial improvements in dose response modeling for risk assessment may result from recent and continuing advances in biological research, biochemical techniques, biostatistical/mathematical methods and computational power. This report provides a ranked set of recommendations for proposed research to advance the state of the art in dose response modeling. The report is the result of a meeting of invited workgroup participants charged with identifying five areas of research in dose response modeling that could be incorporated in a national agenda to improve risk assessment methods. Leading topics of emphasis are interindividual variability, injury risk assessment modeling, and procedures to incorporate distributional methods and mechanistic considerations into now-standard methods of deriving a reference dose (RfD), reference concentration (RfC), minimum risk level (MRL) or similar dose-response parameter estimates.  相似文献   

10.
Pregnancy and maternal body weight development are intertwined in complicated patterns. In most studies, an increase in maternal body weight with age and parity has been reported. For women who develop obesity, pregnancies can, in retrospect, be identified as important triggering life events. In a retrospective analysis of 128 women at our Obesity Unit, 73% of these severely obese patients had retained more than 10 kg in connection with a pregnancy. For the general population, the effect of a pregnancy on future weight development is surprisingly difficult to predict. In The Stockholm Pregnancy and Weight Development Study, the effects of pregnancy on weight retention one year after delivery were studied in 1423 women. Data were collected retrospectively from routine pregnancy records and then extended prospectively 6 and 12 months after delivery. The mean weight retention associated with a pregnancy one year after delivery was estimated to about 0.5 kg, with a range of-12 to 26 kg. Fourteen percent of the women gained more than 5 kg. Weight increase during pregnancy was the strongest predict or for sustained weight retention 1 year later. Pre-pregnancy weight did not predict the weight development outcome. The lactation pattern had only a minor influence on weight development Smoking cessation was an important predictor for sustained weight increase. More weight retention was observed in those women who reported a change in lifestyle as regarded eating habits, meal patterns, and physical activity, suggesting that eventual body weight after pregnancy is more determined by the changes in association with that particular pregnancy than with the lifestyle before.  相似文献   

11.

Objectives

Cryptococcal meningitis (CM)-related mortality may be prevented by screening patients for sub-clinical cryptococcal antigenaemia (CRAG) at antiretroviral-therapy (ART) initiation and pre-emptively treating those testing positive. Prior to programmatic implementation in South Africa we performed a cost-effectiveness analysis of alternative preventive strategies for CM.

Design

Cost-effectiveness analysis.

Methods

Using South African data we modelled the cost-effectiveness of four strategies for patients with CD4 cell-counts <100 cells/µl starting ART 1) no screening or prophylaxis (standard of care), 2) universal primary fluconazole prophylaxis, 3) CRAG screening with fluconazole treatment if antigen-positive, 4) CRAG screening with lumbar puncture if antigen-positive and either amphotericin-B for those with CNS disease or fluconazole for those without. Analysis was limited to the first year of ART.

Results

The least costly strategy was CRAG screening followed by high-dose fluconazole treatment of all CRAG-positive individuals. This strategy dominated the standard of care at CRAG prevalence ≥0.6%. Although CRAG screening followed by lumbar puncture in all antigen-positive individuals was the most effective strategy clinically, the incremental benefit of LPs and amphotericin therapy for those with CNS disease was small and additional costs were large (US$158 versus US$51per person year; incremental cost effectiveness ratio(ICER) US$889,267 per life year gained). Both CRAG screening strategies are less costly and more clinically effective than current practice. Primary prophylaxis is more effective than current practice, but relatively cost-ineffective (ICER US$20,495).

Conclusions

CRAG screening would be a cost-effective strategy to prevent CM-related mortality among patients initiating ART in South Africa. These findings provide further justification for programmatic implementation of CRAG screening.  相似文献   

12.
SCD in pregnancy is associated with increased adverse fetal and maternal outcomes. In Tanzania where the frequency of sickle cell trait is 13% there has been scanty data on SCD in pregnancy. With progressive improvement in childhood survival the burden of SCD in pregnancy will increase. We analyzed all deliveries at Muhimbili National Hospital (MNH) from 1999 to 2011. Fetal and maternal outcomes of SCD deliveries were compared with non-SCD. Data were analyzed using IBM SPSS statistics version 19. Chi square and Fisher Exact tests were used to compare proportions and the independent t-test for continuous data. To predict risks of adverse effects, odds ratios were determined using multivariate logistic regression. A p-value<0.05 was considered significant. In total, 157,473 deliveries occurred at MNH during the study period, of which 149 were SCD (incidence of 95 SCD per 100,000 deliveries). The incidence of SCD had increased from 76 per 100,000 deliveries in the 1999–2002 period to over 100 per 100, 000 deliveries in recent years. The mean maternal age at delivery was lower in SCD (24.0±5.5 years) than in non-SCD deliveries (26.2±6.0 years), p<0.001. Compared with non-SCD (2.9±0.7 Kg), SCD deliveries had less mean birth-weight (2.6±0.6 Kg), p<0.001. SCD were more likely than non-SCD to deliver low APGAR score at 5 minutes (34.5% Vs 15.0%, OR = 3.0, 95%CI: 2.1–4.2), stillbirths (25.7% Vs 7.5%, OR = 4.0, 95%CI: 2.8–5.8). There was excessive risk of maternal deaths in SCD compared to non-SCD (11.4% Vs 0.4%, OR = 29, 95%CI: 17.3–48.1). The leading cause of deaths in SCD was infections in wholly 82% in contrast to only 32% in non-SCD. In conclusion SCD in pregnancy is an emerging problem at MNH with increased adverse fetal outcomes and excessive maternal mortality mainly due to infections.  相似文献   

13.
A novel approach to population-level assessment was applied in order to demonstrate its utility in estimating and managing the risk of zinc in a water environment. Much attention has been paid to population-level risk assessment, but there have been no attempts to determine a “safe” population-level concentration as an environmental criterion. Based on the published results of toxicity tests for various species, we first theoretically derived a threshold concentration at which a population size is unchanged due to the adverse effects of zinc exposure. To derive a zinc concentration that will protect populations in natural environments, we adopted the concept of species sensitivity distribution. Assuming the threshold concentrations of a set of species are log-normally distributed, we calculated the 95% protection level of zinc (PHC5 :population-level hazardous concentration of 5% of species), which is 107 μg/L. Meanwhile, the 95% protection criterion (HC5) based on conventional individual-level chronic toxicity, was calculated to be 14.6 μg/L. The environmentally “safe” concentration for a population-level endpoint is about 7 times greater than that for an individual-level endpoint. The proposed method provides guidance for a pragmatic approach to population-level ecological risk assessment and the management of chemicals.  相似文献   

14.

Background

There is demand from women for alternatives to giving birth in a standard hospital setting however access to these services is limited. This systematic review examines the literature relating to the economic evaluations of birth setting for women at low risk of complications.

Methods

Searches of the literature to identify economic evaluations of different birth settings of the following electronic databases: MEDLINE, CINAHL, EconLit, Business Source Complete and Maternity and Infant care. Relevant English language publications were chosen using keywords and MeSH terms between 1995 and 2015. Inclusion criteria included studies focussing on the comparison of birth setting. Data were extracted with respect to study design, perspective, PICO principles, and resource use and cost data.

Results

Eleven studies were included from Australia, Canada, the Netherlands, Norway, the USA, and the UK. Four studies compared costs between homebirth and the hospital setting and the remaining seven focussed on the cost of birth centre care and the hospital setting. Six studies used a cost-effectiveness analysis and the remaining five studies used cost analysis and cost comparison methods. Eight of the 11 studies found a cost saving in the alternative settings. Two found no difference in the cost of the alternative settings and one found an increase in birth centre care.

Conclusions

There are few studies that compare the cost of birth setting. The variation in the results may be attributable to the cost data collection processes, difference in health systems and differences in which costs were included. A better understanding of the cost of birth setting is needed to inform policy makers and service providers.  相似文献   

15.
The 2013 global roadmap for childhood tuberculosis calls for countries to implement contact screening and provide preventive therapy to children younger than 5 years. Therefore, this study designed to evaluate the implementation status of child contact screening and management in the health facilities of Addis Ababa, Ethiopia. Smear positive TB patients living with children attending daily observed treatment at the TB clinic and health care workers providing service were approached to address the study objective. Structured questionnaires were administered to smear positive index cases living with children whether they were requested to bring children age five year and below for TB screening and to health care providers in HIV, TB and child health clinics to assess their knowledge and practice on contact screening and management. Double data entry and analysis was done using EpiData software 3.1. In 27 health centres, 688 smear-positive index tuberculosis patients were approached of whom 203 (29.5%) reported to have children five years and below in their household. A total of 48 (23.6%) index cases had been requested by the health care workers to bring their children for tuberculosis screening and 45 (93.8%) had complied with this request. Of 230 children living with index smear positive tuberculosis patient, 152 (66.1%) were not screened for tuberculosis, 78 (33.9%) children screened, 2 had tuberculosis, 76 screened negative of which 3 (3.8%) received preventive treatment. None of the health care workers indicated to routinely record and report on child contact management. Household child contact screening and preventive intervention was sub-optimal in Addis Ababa. An important opportunity lost to prevent tuberculosis in young children. Training of health care workers, availing simple symptom based screening tool, and proper documentation could improve implementation.  相似文献   

16.

Background

In adult rats, initial exposure to antigens by a mucosal route triggers tolerance such that any subsequent re-exposure, even by a systemic route, results in suppression of immunity. The newborn’s gut is semi-permeable for a finite period to allow maternal antibodies to enter the newborn’s circulation. We propose that antigens introduced in extreme early life can readily traverse the gut wall and therefore circumvent induction of mucosal tolerance.

Methodology/Principle Findings

Rat pups were gavaged with low-doses of ovalbumin (OVA; oral exposure group) or saline (parenteral control group) every second day for several weeks followed by an intraperitoneal (i.p.) injection at 1 month of age. When gavage was initiated the day after birth, newborn oral exposure pups responded with significantly higher anti-OVA IgA, IgM, IgG2a, and IgG1 titres in their serum and anti-OVA IgA, IgG2a and IgG1 titres in their lungs compared to negative control pups. Oral exposure alone failed to induce immunity. Pups exposed to the same treatment regimen starting at 14 days of age showed induction of mucosal tolerance after i.p. immunization. Newborn oral exposure groups subjected to secondary i.p. immunization responded with significantly increased humoral immunity in lung and sera suggesting that once antigen-specific mucosal tolerance if circumvented, it persists. Lymphocytes derived from mesenteric lymph node cells re-simulated with OVA ex vivo, from newborn oral exposure pups exposed to secondary immunization produced significantly higher IFN-γ expression and lymphocyte proliferation relative to control pups indicating prevention of tolerance in the cell-mediated immune system.

Conclusions/Significance

This work demonstrates that newborns may be uniquely qualified to prevent induction of mucosal tolerance to oral antigens. These results should be further explored to establish whether prevention of tolerance by early life oral vaccination can be exploited to prime for mucosal as well as systemic immunity and thus protect this susceptible population against infectious diseases.  相似文献   

17.
《Endocrine practice》2021,27(8):807-812
ObjectiveTo assess the value of a validated diabetes risk test, the Cambridge Risk Score (CRS), to identify patients admitted to hospital without diabetes at risk for new hyperglycemia (NH).MethodsThis retrospective cross-sectional study included adults admitted to a hospital over a 4-year period. Patients with no diabetes diagnosis and not on antidiabetics were included. The CRS was calculated for each patient, and those with available glycated hemoglobin (HbA1C) results were investigated in a second analysis. Multivariate regression analyses were performed to assess the association among CRS, HbA1C, and the risk for NH.ResultsA total of 19,830 subjects comprised the sample, of which 38% were found to have developed NH, defined as a blood glucose level ≥140 mg/dL. After accounting for covariates, the CRS was significantly associated with NH (odds ratio [OR], 1.19 [1.16, 1.22]; P < .001). Only 17% of patients had their HbA1C values checked within 6 months of admission. Compared with patients without diabetes, patients with prediabetes based on their HbA1C level (OR, 1.59 [1.37, 1.86]; P < .001) and patients with undiagnosed diabetes (OR, 5.95 [3.50, 10.65]; P < .001) were also significantly more likely to have NH.ConclusionResults of this study show that the CRS and HbA1C levels were significantly associated with the risk of developing NH in inpatient adults without diabetes. Given that an HbA1C level was missing in most medical records of hospitalized patients without diabetes, the CRS could be a useful tool for early identification and management of NH, possibly leading to better outcomes.  相似文献   

18.
19.

Background

In March 2012, The Elizabeth Glaser Pediatric AIDS Foundation trained maternal and child health workers in Southern Province of Zambia to use a new rapid syphilis test (RST) during routine antenatal care. A recent study by Bonawitz et al. (2014) evaluated the impact of this roll out in Kalomo District. This paper estimates the costs and cost-effectiveness from the provider''s perspective under the actual conditions observed during the first year of the RST roll out.

Methods

Information on materials used and costs were extracted from program records. A decision-analytic model was used to evaluate the costs (2012 USD) and cost-effectiveness. Basic parameters needed for the model were based on the results from the evaluation study.

Results

During the evaluation study, 62% of patients received a RST, and 2.8% of patients tested were positive (and 10.4% of these were treated). Even with very high RST sensitivity and specificity (98%), true prevalence of active syphilis would be substantially less (estimated at <0.7%). For 1,000 new ANC patients, costs of screening and treatment were estimated at $2,136, and the cost per avoided disability-adjusted-life year lost (DALY) was estimated at $628. Costs change little if all positives are treated (because prevalence is low and treatment costs are small), but the cost-per-DALY avoided falls to just $66. With full adherence to guidelines, costs increase to $3,174 per 1,000 patients and the cost-per-DALY avoided falls to $60.

Conclusions

Screening for syphilis is only useful for reducing adverse birth outcomes if patients testing positive are actually treated. Even with very low prevalence of syphilis (a needle in the haystack), cost effectiveness improves dramatically if those found positive are treated; additional treatment costs little but DALYs avoided are substantial. Without treatment, the needle is essentially found and thrown back into the haystack.  相似文献   

20.
Ecosystems - Mountain fens found in western North America have sequestered atmospheric carbon dioxide (CO2) for millennia, provide important habitat for wildlife, and serve as refugia for...  相似文献   

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