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61.
An autophagy-related gene Atg8 was cloned for the first time from wild emmer wheat, named as TdAtg8, and its role on autophagy under abiotic stress conditions was investigated. Examination of TdAtg8 expression patterns indicated that Atg8 expression was strongly upregulated under drought stress, especially in the roots when compared to leaves. LysoTracker(?) red marker, utilized to observe autophagosomes, revealed that autophagy is constitutively active in Triticum dicoccoides. Moreover, autophagy was determined to be induced in plants exposed to osmotic stress when compared to plants grown under normal conditions. Functional studies were executed in yeast to confirm that the TdATG8 protein is functional, and showed that the TdAtg8 gene complements the atg8?::kan MX yeast mutant strain grown under nitrogen deficiency. For further functional analysis, TdATG8 protein was expressed in yeast and analyzed using Western immunoblotting. Atg8-silenced plants were exposed to drought stress and chlorophyll and malondialdehyde (MDA) content measurements demonstrated that Atg8 plays a key role on drought stress tolerance. In addition, Atg8-silenced plants exposed to osmotic stress were found to have decreased Atg8 expression level in comparison to controls. Hence, Atg8 is a positive regulator in osmotic and drought stress response.  相似文献   
62.
Bioprocess and Biosystems Engineering - In the recent years, there has been considerable debate about the potential impacts of antibiotics present in various environments on the public health and...  相似文献   
63.
The accuracy of risk prediction for coronary artery disease can be improved with the use of novel molecular or genetic biomarkers. In this study, we investigated the difference of five selected microRNAs (miR or miRNA) in patients with coronary artery disease (CAD) and controls, assessed by coronary angiography. The study population consisted of 85 subjects, aged between 18 and 75 years and underwent invasive coronary angiography. Subjects with more than 30% stenosis in at least one coronary artery, patients with a history of prior percutaneous coronary intervention or coronary by-pass surgery were allocated to the patient group; whereas the subjects without at least 30% stenosis consisted the control group. Groups were similar in age, presence of hypertension, and smoking status. However, the proportion of males and subjects taking angiotensin-converting enzyme inhibitors or angiotensin receptor blockers, beta blockers, nitrates, and statins were higher in the patient group. miR-221 and miR-155 were downregulated (P = .02 and .001, respectively), while miR-21 levels were significantly increased (P = .003) in the patient group compared to controls. Changes in miR-145 and miR-126 did not reach statistical significance (P > .05). miRNA- 21, miR-155, and miR-221 were differentially expressed between the patients and controls. miRNAs are promising biomarkers for CAD diagnosis, however, this requires further research with larger groups.  相似文献   
64.
65.
Antifreeze proteins (AFPs) are ice binding proteins found in some plants, insects, and Antarctic fish allowing them to survive at subzero temperatures by inhibiting ice crystal growth. The interaction of AFPs with ice crystals results in a difference between the freezing and melting temperatures, termed thermal hysteresis, which is the most common measure of AFP activity. Creating antifreeze protein constructs that reduce the concentration of protein needed to observe thermal hysteresis activities would be beneficial for diverse applications including cold storage of cells or tissues, ice slurries used in refrigeration systems, and food storage. We demonstrate that conjugating multiple type I AFPs to a polyallylamine chain increases thermal hysteresis activity compared to the original protein. The reaction product is approximately twice as active when compared to the same concentration of free proteins, yielding 0.5 °C thermal hysteresis activity at 0.3 mM protein concentration. More impressively, the amount of protein required to achieve a thermal hysteresis of 0.3 °C is about 100 times lower when conjugated to the polymer (3 μM) compared to free protein (300 μM). Ice crystal morphologies observed in the presence of the reaction product are comparable to those of the protein used in the conjugation reaction.  相似文献   
66.
Transmission of cutaneous leishmaniasis (CL) caused by Leishmania infantum was studied in South Anatolia, Turkey. Small, non-ulcerating lesions prevailed and patients were negative in rK39 tests for antibody detection for human visceral leishmaniasis (VL). The most abundant sand fly species, Phlebotomus tobbi, was found positive for Leishmania promastigotes with a prevalence of 1.4% (13 out of 898 dissected females). The isolated strains were identical with those obtained from patients with CL and were typed as L. infantum. Phylogenetic analysis revealed similarity to MON-188 and a clear difference from the MON-1 clade. Blood-meal identification showed that P. tobbi feeds preferentially on cattle and humans. This finding, the high number of CL patients and relative scarcity of dogs in the focus, suggests that the transmission cycle could be anthroponotic.  相似文献   
67.

Background

Women who survive severe obstetric complications can provide insight into risk factors and potential strategies for prevention of maternal morbidity as well as maternal mortality. We interviewed 32 women, in an urban facility in Ghana, who had experienced severe morbidity defined using a standardized WHO near-miss definition and identification criteria. Women provided personal accounts of their experiences of severe maternal morbidity and perceptions of the care they received.

Methods and Findings

The study took place in a referral facility in urban Accra, and semi-structured interviews were conducted with women who had either a maternal near miss (n = 17) or a potentially life-threatening complication (n = 15). The most common themes surrounding the traumatic delivery were the fear of dying and concern over the potential (or actual) loss of the baby. For many women, the loss of a baby negatively influenced how they viewed and coped with this experience. Women’s perceptions of the quality of the care highlighted several key factors such as the importance of information, good communication and attitudes, and availability of human (i.e., more doctors) and physical resources (i.e., more beds, water) at the facility.

Conclusions

Our results suggest that experiences of women with severe maternal morbidity may inform different aspects of quality improvement in the facilities, which in turn have a positive impact on future health seeking behavior, service utilization and reduction in maternal morbidity and mortality.  相似文献   
68.
There are inconsistent reports regarding cytotoxin-associated gene A (cagA) status of Helicobacter pylori isolates and the severity of the mucosal lesions in children. The aim of this study was to determine the prevalence of cagA(+) strains and to evaluate its correlation with clinic and endoscopic findings. We examined 45 H. pylori strains that were grown on brain-heart infusion agar supplemented with 7% horse blood. Following 72 h of incubation colonies were harvested and bacterial DNA was extracted. Polymerase chain reaction primers F1 and B1 were used to amplify a 348-bp internal fragment of cagA. The prevalence of cagA in Turkish pediatric patients was 55.6%. No association was found between cagA status and the severity of gastro-duodenal lesions.  相似文献   
69.
Chronic liver disease and cirrhosis are two of the most important health problems according to current gastroenterology literature. Based on the recent developments in the field of immunology, advanced follow-up and treatment modalities have been introduced for these disorders. Immune defence against viral infections depends on effective cellular immune responses derived mainly from Th1-related cytokines. Th2 type immune responses can inhibit efficient immune function by secretion of several cytokines such as IL-10, TGF-beta1. In this particular study, we determined the serum levels of TGF-beta1, which plays a role in immune suppression and induction of tissue fibrosis. We evaluated the role of TGF-beta1 in the pathogenesis of chronic liver disease and cirrhosis. Fourteen chronic hepatitis B (CHB), 12 chronic hepatitis C (CHC) patients and 21 cirrhotic patients were enrolled in the study. The control group consisted of ten healthy people. Serum TGF-beta1 levels were higher in both cirrhosis and CHC group when compared to those in CHB and control groups (P < 0.05). Although serum TGF-beta1 levels in the cirrhosis group were higher than that in the CHC group, the difference was not statistically significant. In conclusion, elevated TGF-beta1 levels in patients with CHC and cirrhosis may have a role in the pathogenesis and chronicity of these diseases.  相似文献   
70.
Cutaneous leishmaniasis is one of the most important vector-borne endemic diseases in Turkey. The main objective of this study was to evaluate the influence of temperature on the developmental rates of one important vector of leishmaniasis, Phlebotomus papatasi (Scopoli, 1786) (Diptera: Psychodidae). Eggs from laboratory-reared colonies of Phlebotomus papatasi were exposed to six constant temperature regimes from 15 to 32 degrees C with a daylength of 14 h and relative humidity of 65-75%. No adult emergence was observed at 15 degrees C. Complete egg to adult development ranged from 27.89 +/- 1.88 days at 32 degrees C to 246.43 +/- 13.83 days at 18 degrees C. The developmental zero values were estimated to vary from 11.6 degrees C to 20.25 degrees C depending on life stages, and egg to adult development required 440.55 DD above 20.25 degrees C.  相似文献   
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