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121.

Background

Olive plant leaves (Olea europaea L.) have been used for centuries in folk medicine to treat diabetes, but there are very limited data examining the effects of olive polyphenols on glucose homeostasis in humans.

Objective

To assess the effects of supplementation with olive leaf polyphenols (51.1 mg oleuropein, 9.7 mg hydroxytyrosol per day) on insulin action and cardiovascular risk factors in middle-aged overweight men.

Design

Randomized, double-blinded, placebo-controlled, crossover trial in New Zealand. 46 participants (aged 46.4±5.5 years and BMI 28.0±2.0 kg/m2) were randomized to receive capsules with olive leaf extract (OLE) or placebo for 12 weeks, crossing over to other treatment after a 6-week washout. Primary outcome was insulin sensitivity (Matsuda method). Secondary outcomes included glucose and insulin profiles, cytokines, lipid profile, body composition, 24-hour ambulatory blood pressure, and carotid intima-media thickness.

Results

Treatment evaluations were based on the intention-to-treat principle. All participants took >96% of prescribed capsules. OLE supplementation was associated with a 15% improvement in insulin sensitivity (p = 0.024) compared to placebo. There was also a 28% improvement in pancreatic β-cell responsiveness (p = 0.013). OLE supplementation also led to increased fasting interleukin-6 (p = 0.014), IGFBP-1 (p = 0.024), and IGFBP-2 (p = 0.015) concentrations. There were however, no effects on interleukin-8, TNF-α, ultra-sensitive CRP, lipid profile, ambulatory blood pressure, body composition, carotid intima-media thickness, or liver function.

Conclusions

Supplementation with olive leaf polyphenols for 12 weeks significantly improved insulin sensitivity and pancreatic β-cell secretory capacity in overweight middle-aged men at risk of developing the metabolic syndrome.

Trial Registration

Australian New Zealand Clinical Trials Registry #336317.  相似文献   
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123.

Background

There are sex differences in the risk of development of cardiovascular disease (CVD). According to the developmental origins of health and disease paradigm (DOHaD), CVD originates in fetal life. This study examines fetal sex differences in cardiovascular development in utero.

Methods

In 1028 pregnant women, we assessed fetal circulation using pulsed wave Doppler examinations between 28 and 34 weeks gestation. To test associations between fetal sex and fetal circulation measurements, linear regression models were used adjusting for fetal size, gestational age, and fetal heart rate.

Results

A higher pulsatility index in the ductus venosus was observed in male fetuses compared to female fetuses (difference 0.02, 95 % CI 0.01; 0.05) with a lower E/A ratio of the tricuspid (difference ?0.01, 95 % CI ?0.03; ?0.00) and mitral (difference ?0.02, 95 % CI ?0.03; ?0.01) valves. This was mainly determined by differences in the E wave of the tricuspid and mitral valves (differences ?1.02, 95 % CI ?1.81; ?0.24 and ?1.28, 95 % CI ?2.11; ?0.46, respectively). Also in males, a lower peak systolic velocity was seen in the pulmonary artery (difference ?1.33, 95 % CI ?2.63; ?0.03) with a similar lower trend regarding peak systolic velocity in the ascending aorta.

Conclusions

Male fetuses exhibit an increased preload and reduced afterload conditions compared to females. While it is difficult to relate these measurements to exact cardiac function, our findings strongly suggest that the known differences in cardiovascular performance between the sexes already start in utero.
  相似文献   
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125.
We describe a new family of repetitive elements in the genome of the archaebacterium Halobacterium volcanii. There are some 20-30 copies of this element, which we designate ISH51. Sequenced copies show typical insertion sequence characteristics (terminal inverted repeats, direct flanking repeats of "target site" DNA). However, members of the ISH51 family are highly heterogeneous, showing on average only 85% primary sequence homology; and some genomic copies appear to be severely truncated. Some ISH51 elements are clustered together in regions of relatively AT-rich DNA. There are at least five such AT-rich "islands" in the H. volcanii genome. Repetitive sequences homologous to ISH51 are found in the genomes of most Halobacterium and Halococcus species.  相似文献   
126.

Background  

The shape of phylogenetic trees has been used to make inferences about the evolutionary process by comparing the shapes of actual phylogenies with those expected under simple models of the speciation process. Previous studies have focused on speciation events, but gene duplication is another lineage splitting event, analogous to speciation, and gene loss or deletion is analogous to extinction. Measures of the shape of gene family phylogenies can thus be used to investigate the processes of gene duplication and loss. We make the first systematic attempt to use tree shape to study gene duplication using human gene phylogenies.  相似文献   
127.

Introduction

Family planning contributes significantly to the prevention of maternal and child mortality. However, many women still do not use modern contraception and the numbers of unintended pregnancies, abortions and subsequent deaths are high. In this paper, we estimate the service delivery costs of scaling up modern contraception, and the potential impact on maternal, newborn and child survival in South Africa.

Methods

The Family Planning model in Spectrum was used to project the impact of modern contraception on pregnancies, abortions and births in South Africa (2015-2030). The contraceptive prevalence rate (CPR) was increased annually by 0.68 percentage points. The Lives Saved Tool was used to estimate maternal and child deaths, with coverage of essential maternal and child health interventions increasing by 5% annually. A scenario analysis was done to test impacts when: the change in CPR was 0.1% annually; and intervention coverage increased linearly to 99% in 2030.

Results

If CPR increased by 0.68% annually, the number of pregnancies would reduce from 1.3 million in 2014 to one million in 2030. Unintended pregnancies, abortions and births decrease by approximately 20%. Family planning can avert approximately 7,000 newborn and child and 600 maternal deaths. The total annual costs of providing modern contraception in 2030 are estimated to be US$33 million and the cost per user of modern contraception is US$7 per year. The incremental cost per life year gained is US$40 for children and US$1,000 for mothers.

Conclusion

Maternal and child mortality remain high in South Africa, and scaling up family planning together with optimal maternal, newborn and child care is crucial. A huge impact can be made on maternal and child mortality, with a minimal investment per user of modern contraception.  相似文献   
128.
Data are presented on the spleen and thymus structure, time of appearance of the lymphocytes and their heterogeneity in the liver, thymus, spleen, lymph nodes and blood of human foetuses with hemochorial placenta (3 to 34 weeks) and of the minipigs foetuses with epitheliochorial placenta (32 to 95 days). In both foetuses the first T- and B-lymphocytes are found in liver, T-lymphocytes are then found in thymus and later in spleen and lymph nodes whereas B-lymphocytes are found, after liver, in spleen. Kinetics of T- and B-lymphocytes during embryogenesis is described. Reaction of the minipig lymphocytes to mitogens was demonstrated.  相似文献   
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