Preeclampsia is believed to result from release of placental factors that damage maternal vascular endothelium. However, because most studies have been conducted during pregnancy, it has not been ...possible to separate maternal from placental mechanisms underlying endothelial dysfunction in preeclampsia.
To determine whether endothelial function is impaired in nonpregnant women with previous preeclampsia and whether endothelial dysfunction is mediated by oxidative stress.
Case-control study conducted at 3 hospital maternity units in London, England, between July 1997 and June 2000.
A total of 113 women with previous preeclampsia (n = 35 with recurrent episodes; n = 78 with a single episode) and 48 women with previous uncomplicated pregnancies, all of whom were at least 3 months (median, 3 years) postpartum.
Brachial artery flow-mediated (endothelium-dependent) and glyceryl trinitrate-induced (endothelium-independent) dilatation were compared between previously preeclamptic women and controls. To investigate oxidative stress, these measurements were repeated after administration of ascorbic acid, 1 g intravenously, in 15 cases and 15 controls.
Mean (SD) flow-mediated dilatation was lower in women with previous preeclampsia compared with controls (recurrent group, 0.9% 4.1%; single-episode group, 2.7% 3.5%; and control group, 4.7% 4.3%; P<.001). In contrast, glyceryl trinitrate-induced dilatation was similar in the 3 groups (recurrent, 19.5% 5.9%; single-episode, 21.0% 8.0%; and control, 21.0% 8.3%; P =.65). Impaired flow-mediated dilatation in previously preeclamptic women was not accounted for by recognized vascular risk factors. Ascorbic acid administration increased flow-mediated dilatation in previously preeclamptic women (baseline, 2.6% 3.3%; after administration, 5.6% 3.0%; P =.001) but not in controls (baseline, 6.2% 3.3%; after administration, 6.7% 5.0%; P =.72).
Our results indicate that endothelial function is impaired in women with previous preeclampsia and is not explained by established maternal risk factors but is reversed by antioxidant ascorbic acid administration.
Seasonal, pandemic, and avian influenza virus infections may be associated with central nervous system pathology, albeit with varying frequency and different mechanisms. Here, we demonstrate that ...differentiated human astrocytic (T98G) and neuronal (SH-SY5Y) cells can be infected by avian H7N9 and pandemic H1N1 viruses. However, infectious progeny viruses can only be detected in H7N9 virus infected human neuronal cells. Neither of these viral strains can generate infectious progeny virus in human astrocytes despite replication of viral genome was observed. Furthermore, H7N9 virus triggered high pro-inflammatory cytokine expression, while pandemic H1N1 virus induced only low cytokine expression in either brain cell type. The experimental finding here is the first data to demonstrate that avian H7N9 virus can infect, transcribe, and replicate its viral genome; induce cytokine upregulation; and cause cytopathic effects in human brain cells, which may potentially lead to profound central nervous system injury. Observation for neurological problems due to H7N9 virus infection deserves further attention when managing these patients.
Abstract In recent decades, temporal patterns in SSB intake have shown a close parallel between the upsurge in obesity and rising levels of SSB consumption. SSBs are beverages that contain added ...caloric sweeteners such as sucrose, high-fructose corn syrup or fruit-juice concentrates, all of which result in similar metabolic effects. They include the full spectrum of soft drinks, carbonated soft drinks, fruitades, fruit drinks, sports drinks, energy and vitamin water drinks, sweetened iced tea, cordial, squashes, and lemonade, which collectively are the largest contributor to added sugar intake in the US. It has long been suspected that SSBs have an etiologic role in the obesity epidemic, however only recently have large epidemiological studies been able to quantify the relationship between SSB consumption and long-term weight gain, type 2 diabetes (T2DM) and cardiovascular disease (CVD) risk. Experimental studies have provided important insight into potential underlying biological mechanisms. It is thought that SSBs contribute to weight gain in part by incomplete compensation for energy at subsequent meals following intake of liquid calories. They may also increase risk of T2DM and CVD as a contributor to a high dietary glycemic load leading to inflammation, insulin resistance and impaired β-cell function. Additional metabolic effects from the fructose fraction of these beverages may also promote accumulation of visceral adiposity, and increased hepatic de novo lipogenesis, and hypertension due to hyperuricemia. Consumption of SSBs should therefore be replaced by healthy alternatives such as water, to reduce risk of obesity and chronic diseases.
To land on a surface the bat needs to get a grip with their tiny feet, which are interconnected to the wings via the inner wing membrane (the plagiopatagium) and therefore quite immobile. Because the ...bat has to slow down just before initiating the somersault, this prevents the use of aerodynamic forces–these are small anyway at such low speeds, and the proximity to the landing site prevents vigorous flapping. The transgenic LUSHD118A did not result in the enhanced OSN activity that Laughlin et al. had observed in the infusion experiment. ...these neurons retained the ability to be activated by cVA, and lush mutant flies expressing additional LUSH mutant proteins at endogenous levels didn’t recapitulate the increased or decreased cVA sensitivity shown by Laughlin et al. ...the authors show that multicellular organisms comprising these high-mutation cells are less fit. ...their experiments not only provide valuable insight into ancient evolutionary transitions to multicellularity but may also guide studies of reversion to unicellularity, whereby cancerous cells arise by flouting rules governing replication or quiescence in multicellular organisms. First some background: since roughly the 1970s, various government authorities have required that research proposing to use nonhuman animals undergo an independent review and approval process before it is conducted.
Genetic Complementation in Apicomplexan Parasites Striepen, Boris; White, Michael W.; Li, Catherine ...
Proceedings of the National Academy of Sciences - PNAS,
04/2002, Letnik:
99, Številka:
9
Journal Article
Recenzirano
Odprti dostop
A robust forward genetic model for Apicomplexa could greatly enhance functional analysis of genes in these important protozoan pathogens. We have developed and successfully tested a genetic ...complementation strategy based on genomic insertion in Toxoplasma gondii. Adapting recombination cloning to genomic DNA, we show that complementing sequences can be shuttled between parasite genome and bacterial plasmid, providing an efficient tool for the recovery and functional assessment of candidate genes. We show complementation, gene cloning, and biological verification with a mutant parasite lacking hypoxanthine-xanthine-guanine phosphoribosyltransferase and a T. gondii cDNA library. We also explored the utility of this approach to clone genes based on function from other apicomplexan parasites using Toxoplasma as a surrogate. A heterologous library containing Cryptosporidium parvum genomic DNA was generated, and we identified a C. parvum gene coding for inosine 5-monophosphate-dehydrogenase (IMPDH). Interestingly, phylogenetic analysis demonstrates a clear eubacterial origin of this gene and strongly suggests its lateral transfer from ε-proteobacteria. The prokaryotic origin of this enzyme might make it a promising target for therapeutics directed against Cryptosporidium.
Data on spirometrically defined chronic airflow limitation (CAL) are scarce in developing countries.
To estimate the prevalence of spirometrically defined CAL in Kashmir, North India.
Using Burden of ...Obstructive Lung Disease survey methods, we administered questionnaires to randomly selected adults aged ⩾40 years. Post-bronchodilator spirometry was performed to estimate the prevalence of CAL and its relation to potential risk factors.
Of 1100 participants initially recruited, 953 (86.9%) responded and 757 completed acceptable spirometry and questionnaires. The prevalence of a forced expiratory volume in 1 s/forced vital capacity (FEV
/FVC) ratio less than the lower limit of normal was 17.3% (4.5) in males and 14.8% (2.1) in females. Risk factors for CAL included higher age, cooking with wood and lower educational status. The prevalence of current smoking was 61% in males and 22% in females; most smoked hookahs. CAL was found equally in non-smoking males and females, and was independently associated with the use of the hookah, family history of respiratory disease and poor education. A self-reported doctor's diagnosis of chronic obstructive pulmonary disease was reported in 8.4/1000 (0.9% of females and 0.8% of males).
Spirometrically confirmed CAL is highly prevalent in Indian Kashmir, and seems to be related to the high prevalence of smoking, predominantly in the form of hookah smoking.
Phylogenetic analyses suggest that long-terminal repeat (LTR) bearing retrotransposable elements can acquire additional open-reading frames that can enable them to mediate infection. Whereas this ...process is best documented in the origin of the vertebrate retroviruses and their acquisition of an envelope (env) gene, similar independent events may have occurred in insects, nematodes, and plants. The origins of env-like genes are unclear, and are often masked by the antiquity of the original acquisitions and by their rapid rate of evolution. In this report, we present evidence that in three other possible transitions of LTR retrotransposons to retroviruses, an envelope-like gene was acquired from a viral source. First, the gypsy and related LTR retrotransposable elements (the insect errantiviruses) have acquired their envelope-like gene from a class of insect baculoviruses (double-stranded DNA viruses with no RNA stage). Second, the Cer retroviruses in the Caenorhabditis elegans genome acquired their envelope gene from a Phleboviral (single ambisense-stranded RNA viruses) source. Third, the Tas retroviral envelope (Ascaris lumricoides) may have been obtained from Herpesviridae (double-stranded DNA viruses, no RNA stage). These represent the only cases in which the env gene of a retrovirus has been traced back to its original source. This has implications for the evolutionary history of retroviruses as well as for the potential ability of all LTR-retrotransposable elements to become infectious agents.
PDF
