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71.
72.
Given the multiple permutations in craniofacial malformations, classification of median craniofacial dysplasia or midline Tessier no. 0 to 14 clefts has been difficult and disjointed. In this review, the authors present a summary of normal embryology, prior terminology, and their proposed new classification system. Median craniofacial dysplasia has tissue agenesis and holoprosencephaly at one end (the hypoplasias), frontonasal hyperplasia and excessive tissue (the hyperplasias) at the other end, and abnormal splitting or clefting and normal tissue volume (dysraphia) occupying the middle portion of the spectrum. These three distinct subclassifications have different forms of anomalies within their groups.  相似文献   
73.
In barley, three genes are responsible for the vernalization requirement: VrnH1, VrnH2 and VrnH3. The winter growth habit of barley requires the presence of a recessive VrnH1 allele, together with an active VrnH2 allele. The candidate for VrnH3 (HvFT1) has been recently identified, with evidences pointing at a central role in the integration of the vernalization and photoperiod pathways. Functional polymorphisms have been proposed, but experimental evidence of their role on agronomic performance and adaptation is needed. We examined allelic variation at the promoter and intron 1 of the HvFT1 gene in a landrace collection of barley, finding a high diversity level, with its geographic distribution correlated with latitude. Focusing on genotypes with winter alleles in VrnH1 and VrnH2, an association analysis of the four main HvFT1 haplotypes found in the landrace collection detected differences in time to flowering. Landraces with the intron 1 TC allele, prevalent in the south, flowered 6?C7?days earlier than those with the AG allele, under natural conditions. These results were validated in an independent F2 population. In both data sets, the effect found was similar, but in opposite direction to that described in literature. The polymorphism reported at intron 1 contributes to variation in flowering time under field conditions. We have found that polymorphisms at the promoter also contribute to the effect of the gene on flowering time under field and controlled conditions. The variety of HvFT1 alleles described constitutes an allelic series that may have been a factor in agro-ecological adaptation of barley.  相似文献   
74.
The schistosomal parasite plays a critical role in the development of malignant lesions in different organs. The pathogenesis of cancer is currently under intense investigation to identify reliable prognostic indices for disease detection. The objective of this paper is to evaluate certain biochemical parameters as diagnostic tools to efficiently differentiate between colonic carcinoma and colonic carcinoma associated with schistosomal infection among Egyptian patients. The parameters under investigation are interleukin 2 (IL-2), tumour necrosis factor alpha (TNF-α), carcinoembryonic antigen (CEA) levels, tissue telomerase, pyruvate kinase (PK), glucose-6-phosphate dehydrogenase (G-6-PD) and lactate dehydrogenase (LDH) enzyme activities. The results revealed a significant elevation in the level of the tumour markers IL-2, TNF-α and CEA as well as the activities of LDH, telomerase and G-6-PD among non-bilharzial and bilharzial colonic cancer groups, with a more potent effect in bilharzial infection-associated colonic cancer. A significant inhibition in PK activity was recorded in the same manner as compared to normal tissues. The efficacy of this biomarker was also evaluated through detecting sensitivity, specificity, negative and positive predictive values. In conclusion, schistosomal colonic carcinoma patients displayed more drastic changes in all parameters under investigation. The combination of the selected parameters succeeded in serving as biomarkers to differentiate between the two malignant types.  相似文献   
75.

Background

All organisms may be affected by humans'' increasing impact on Earth, but there are many potential drivers of population trends and the relative importance of each remains largely unknown. The causes of spatial patterns in population trends and their relationship with animal responses to human proximity are even less known.

Methodology/Principal Finding

We investigated the relationship between population trends of 193 species of bird in North America, Australia and Europe and flight initiation distance (FID); the distance at which birds take flight when approached by a human. While there is an expected negative relationship between population trend and FID in Australia and Europe, we found the inverse relationship for North American birds; thus FID cannot be used as a universal predictor of vulnerability of birds. However, the analysis of the joint explanatory ability of multiple drivers (farmland breeding habitat, pole-most breeding latitude, migratory habit, FID) effects on population status replicated previously reported strong effects of farmland breeding habitat (an effect apparently driven mostly by European birds), as well as strong effects of FID, body size, migratory habit and continent. Farmland birds are generally declining.

Conclusions/Significance

Flight initiation distance is related to population trends in a way that differs among continents opening new research possibilities concerning the causes of geographic differences in patterns of anti-predator behavior.  相似文献   
76.

Aims

Non-alcoholic fatty liver disease and its precursor hepatic steatosis is common in obesity and type-2 diabetes and is associated with cardiovascular disease (CVD). Men with type-2 diabetes and/or CVD have a high prevalence of testosterone deficiency. Testosterone replacement improves key cardiovascular risk factors. The effects of testosterone on hepatic steatosis are not fully understood.

Main methods

Testicular feminised (Tfm) mice, which have a non-functional androgen receptor (AR) and very low serum testosterone levels, were used to investigate testosterone effects on high-cholesterol diet-induced hepatic steatosis.

Key findings

Hepatic lipid deposition was increased in Tfm mice and orchidectomised wild-type littermates versus intact wild-type littermate controls with normal androgen physiology. Lipid deposition was reduced in Tfm mice receiving testosterone treatment compared to placebo. Oestrogen receptor blockade significantly, but only partially, reduced the beneficial effects of testosterone treatment on hepatic lipid accumulation. Expression of key regulatory enzymes of fatty acid synthesis, acetyl-CoA carboxylase alpha (ACACA) and fatty acid synthase (FASN) were elevated in placebo-treated Tfm mice versus placebo-treated littermates and Tfm mice receiving testosterone treatment. Tfm mice on normal diet had increased lipid accumulation compared to littermates but significantly less than cholesterol-fed Tfm mice and demonstrated increased gene expression of hormone sensitive lipase, stearyl-CoA desaturase-1 and peroxisome proliferator-activated receptor-gamma but FASN and ACACA were not altered.

Significance

An action of testosterone on hepatic lipid deposition which is independent of the classic AR is implicated. Testosterone may act in part via an effect on the key regulatory lipogenic enzymes to protect against hepatic steatosis.  相似文献   
77.
Our study reports the triglyceride (triacylglycerol, TAG) composition of five new Tunisian virgin olive oil cultivars obtained through controlled crossings of the cultivar (cv.) Chemlali Sfax. These cultivars have been selected among a progeny of 500 olive descendants, based on an evaluation of the fatty‐acid (FA) composition of their oils. Among these samples, two were derived from the crossing with the cv. Sigoise as pollinator (SM634) or pollen acceptor (SM1110) and the others from the crossing with the cv. Meski as pollen acceptor (SM513, SM514, and SM517). The five descendants were characterized by a good fat value, a balanced FA composition, and a high content of triolein, varying between 26.9 (SM514) and 45.46% (SM1110). They had an improved FA composition as compared to that of the cv. Chemlali Sfax and their fruits were slightly bigger. The principal component analysis suggested that the TAG variables were more suitable than the total FAs for an optimum classification of the cultivar samples analyzed. The cultivars obtained through the crossing with the cv. Sigoise (as pollen acceptor or pollinator) had a more favorable composition of FAs and TAG than those obtained through the crossing with the cv. Meski, which indicated that genetic factors had the most important influence on the quality of the virgin olive oils.  相似文献   
78.
Rat cytosolic sialidase is expressed at elevated levels in skeletal muscle and is believed to play a role in the myogenic differentiation of muscle cells. Here, we observed varying levels of enhancement of sialidase activity in the presence a range of divalent cations. In particular, a significant enhancement of activity was observed in the presence of Ca2+. Conversely, inhibition of the sialidase activity was found when the enzyme was incubated in the presence of Cu2+, EDTA, and a range of carbohydrate-based inhibitors. Finally, an investigation of the enzymatic hydrolysis of a synthetic substrate, 4-methylumbelliferyl N-acetyl-alpha-D-neuraminide, by 1H NMR spectroscopy revealed that the reaction catalysed by rat skeletal muscle cytosolic sialidase proceeds with overall retention of anomeric configuration. This result further supports the notion that all sialidases appear to be retaining enzymes.  相似文献   
79.
80.
Insulin resistance is a hallmark feature of type-2 diabetes mellitus (T2DM). We determined the homeostatic model assessment insulin resistance (HOMA-IR) and evaluated its association with C-peptide, insulin, fasting blood glucose (FBG) and glycated hemoglobin (HbA1c) in T2DM patients and non-diabetic subjects. This study comprised a total of 47 T2DM patients and 38 non-diabetic controls. Venous blood samples from all the subjects were collected and sera were analyzed for FBG, HbA1c, insulin and C-peptide using an autoanalyzer. HOMA-IR was calculated using the following equation: HOMA-IR?=?fasting insulin (µU/ml)?×?fasting glucose (mmol/L)/22.5. There was a significant increase in the levels of FBG and HbA1c in diabetic patients. Although the levels of C-peptide and insulin did not differ significantly between the two groups, a significant increase in HOMA-IR was observed in T2DM patients. Both insulin and C-peptide were significantly correlated with HOMA-IR. In conclusion, C-peptide may serve as a simple and convenient predictor of HOMA-IR.  相似文献   
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