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71.

Objectives:

To report on the changes in fibrinolytic activity in human immunodeficiency virus (HIV) infected pregnant women who are undergoing highly active antiretroviral therapy (HAART).

Methods:

Blood was collected from 50 HIV positive women on HAART (test subjects), and 50 HIV positive women not on HAART (controls). These women were attending the prevention of mother to child clinic (PMTCT) of the University of Benin Teaching Hospital, Benin City, Nigeria from January to June 2014. Standard manual techniques were used to estimate plasma fibrinogen concentration (PFC), euglobulin lysis time (ELT), packed cell volume (PCV), and plasma viscosity (PV).

Results:

The mean ± standard error of mean (SEM) of PFC was 4.02±0.13g/l and ELT from the test subjects was 378±15 mins was significantly higher (p<0.05) compared with the control subjects (PFC 3.46±0.12g/l and ELT 267±9.0mins). The PCV or hematocrit values in the test subject was 29.1±0.38%, which was significantly lower (p<0.05) compared with the control subject (31.3±0.43%). The PV in the test subject was 1.76±0.02 mPa/s, while the control subjects was higher (1.73±0.02 mPa/s). This increase was not statistically significant (p>0.05). There were differences in the various parameters investigated when the various trimesters were compared. These differences did not, however, follow a particular pattern.

Conclusion:

Highly active antiretroviral therapy can cause changes in fibrinolytic activity that may predispose pregnant women to hyperfibrinogenemia and anemia.During pregnancy the physiology of a woman is temporary changed to accommodate the newly developing fetus.1 Conception occurs during ovulation, which is approximately on the fourteenth day of a regular menstrual cycle. In conception, the ovum is fertilized in the fallopian tube and becomes a zygote, which is then carried into the uterus. There are changes in the coagulation and fibrinolytic system during pregnancy and knowledge of these physiological changes characterized by hemodilution, changes in the concentration of one or more plasma protein fractions, and reduced fibrinolytic activity is necessary to manage 2 of the more serious problems in pregnancy; namely hemorrhage and thrombo-embolic diseases.2 Increased levels of plasma proteins and reduced fibrinolytic activity have been reported in pregnancy,3 while prolonged euglobulin lysis time (ELT) and increased levels of fibrinogen have also been observed in pregnancy.4 While numerous studies have examined optimal methods for prevention of mother to child transmission of human immunodeficiency virus (HIV) and subsequent response to HAART,5 as well as the impact of pregnancy on outcomes of HIV in the pre-HAART era,6 little is known of the impact of pregnancy on response to HAART in Africa. There are several biologically plausible mechanisms that might alter efficacy of several antiretroviral agents including changes in enzyme activity and beta-estradiol levels, pregnancy-related changes in blood volume and body mass index, and factors which may compromise adherence to HAART ante and post-partum, such as nausea/vomiting, labor-associated morbidity, or responsibility for a new infant.7 Human immunodeficiency virus infected patients have been reported to be at risk of cardiovascular diseases, (CVD) mostly due to the use of antiretroviral agents.8,9 Protease inhibitors have been mostly implicated.10 All these are also connected to fat redistribution dyslipidemia and insulin resistance observed in HIV patients;11,12 thus, this study aims to report on the changes in fibrinolytic activity in HIV infected pregnant women who are undergoing HAART.  相似文献   
72.
Out of 690 allogeneic matched sibling donor transplants for multiple myeloma reported to the European Group for Blood and Marrow Transplantation (EBMT) registry, 334 were performed during the period 1983-93 (all with bone marrow) and 356 during 1994-98 [223 with bone marrow and 133 with peripheral blood stem cells (PBSCs)]. The median overall survival was 10 months for patients transplanted during the earlier time period and 50 months for patients transplanted with hone marrow during the later period. The use of PBSCs was associated with earlier engraftment but no significant survival benefit compared to bone marrow transplants during the same time period. The improvement in survival since 1994 with the result of a significant reduction in transplant-related mortality, which was 38%, 21% and 25% at 6 months and 46%, 30% and 37% at 2 years during the earlier period, and the later period with bone marrow and PBSCs respectively. Reasons for the reduced transplant-related mortality appeared to be fewer deaths owing to bacterial and fungal infections and interstitial pneumonitis, in turn a result of earlier transplantation and less prior chemotherapy. Better supportive treatment and more frequent use of cytokines may also play a role. The improvement in survival was not directly related to the increased use of PBSCs.  相似文献   
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One of the main challenges to malaria elimination is the resilience of vectors, such as Anopheles arabiensis, that evade lethal exposure to insecticidal control measures or express resistance to their active ingredients. This study investigated a novel technology for population control that sterilizes mosquitoes using pyriproxyfen, a juvenile hormone analogue. Females of An. arabiensis were released in a semifield system divided into four equal sections, and each section had a mud hut sheltering a tethered cow providing a blood source for mosquitoes. In all sections, the inner mud hut walls and roofs were lined with black cotton cloth. In one-half of the sections, the cloth was dusted with pyriproxyfen. An overwhelming 96% reduction in adult production was achieved in pyriproxyfen-treated sections compared with control sections. This unprecedented level of control can be exploited to design new vector control strategies that particularly target existing behaviorally resilient and insecticide-resistant populations.  相似文献   
76.
This study investigated the pharmacological inhibition of the toll‐like receptor 4 (TLR4) genes as a measure to attenuate microcystin‐LR (MC‐LR) reproductive toxicity. Bovine Sertoli cells were pretreated with TLR4‐IN‐C34 (C34) for 1 hour. Thereafter the pretreated and non‐pretreated Sertoli cells were cultured in medium containing 10% heat‐activated fetal bovine serum + 80 μg/L MC‐LR for 24 hours to assess the ability of TLR4‐IN‐C34 to attenuate the toxic effects of MC‐LR. The results showed that TLR4‐IN‐C34 inhibited MC‐LR‐induced mitochondria membrane damage, mitophagy and downregulation of blood‐testis barrier constituent proteins via TLR4/nuclear factor‐kappaB and mitochondria‐mediated apoptosis signaling pathway blockage. The downregulation of the mitochondria electron transport chain, energy production and DNA replication related genes (mt‐ND2, COX‐1, COX‐2, ACAT, mtTFA) and upregulation of inflammatory cytokines (interleukin [IL]‐6, tumor necrosis factor‐α, IL‐1β, interferon‐γ, IL‐4, IL‐10, IL‐13 and transforming growth factor β1) were modulated by TLR4‐IN‐C34. Taken together, we conclude that TLR4‐IN‐C34 inhibits MC‐LR‐related disruption of mitochondria membrane, mitophagy and downregulation of blood‐testis barrier proteins of the bovine Sertoli cell via cytochrome c release and TLR4 signaling blockage.  相似文献   
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The outcome of older (≥ 60 years) acute myeloid leukemia (AML) patients is poor, and novel treatments are needed. In a phase 2 trial for older AML patients, low-dose (20 mg/m(2) per day for 10 days) decitabine, a DNA hypomethylating azanucleoside, produced 47% complete response rate with an excellent toxicity profile. To assess the genome-wide activity of decitabine, we profiled pretreatment and post treatment (day 25/course 1) methylomes of marrow samples from patients (n = 16) participating in the trial using deep-sequencing analysis of methylated DNA captured by methyl-binding protein (MBD2). Decitabine significantly reduced global methylation compared with pretreatment baseline (P = .001). Percent marrow blasts did not correlate with global methylation levels, suggesting that hypomethylation was related to the activity of decitabine rather than to a mere decrease in leukemia burden. Hypomethylation occurred predominantly in CpG islands and CpG island-associated regions (P ranged from .03 to .04) A significant concentration (P < .001) of the hypomehtylated CpG islands was found in chromosome subtelomeric regions, suggesting a differential activity of decitabine in distinct chromosome regions. Hypermethylation occurred much less frequently than hypomethylation and was associated with low CpG content regions. Decitabine-related methylation changes were concordant with those previously reported in distinct genes. In summary, our study supports the feasibility of methylome analyses as a pharmacodynamic endpoint for hypomethylating therapies.  相似文献   
80.
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