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121.
Mass effect from polycystic kidney and liver enlargement can result in significant clinical complications and symptoms in autosomal dominant polycystic kidney disease (ADPKD). In this single-center study, we examined the correlation of height-adjusted total liver volume (htTLV) and total kidney volume (htTKV) by CT imaging with hepatic complications (n = 461) and abdominal symptoms (n = 253) in patients with ADPKD. “Mass-effect” complications were assessed by review of medical records and abdominal symptoms, by a standardized research questionnaire. Overall, 91.8% of patients had 4 or more liver cysts on CT scans. Polycystic liver disease (PLD) was classified as none or mild (htTLV < 1,600 mL/m); moderate (1,600 ≤ htTLV <3,200 mL/m); and severe (htTLV ≥ 3,200 mL/m). The prevalence of moderate and severe PLD in our patient cohort was 11.7% (n = 54/461) and 4.8% (n = 22/461), respectively, with a female predominance in both the moderate (61.1%) and severe (95.5%) PLD groups. Pressure-related complications such as leg edema (20.4%), ascites (16.6%), and hernia (3.6%) were common, and patients with moderate to severe PLD exhibited a 6-fold increased risk (compared to no or mild PLD) for these complications in multivariate analysis. Similarly, abdominal symptoms including back pain (58.8%), flank pain (53.1%), abdominal fullness (46.5%), and dyspnea/chest-discomfort (44.3%) were very common, and patients with moderate to severe PLD exhibited a 5-fold increased risk for these symptoms. Moderate to severe PLD is a common and clinically important problem in ~16% of patients with ADPKD who may benefit from referral to specialized centers for further management.  相似文献   
122.
A recombinant plasmid pβCBD was constructed for immobilization of Cellulomonas fimi β-glucosidase (Cbg) using the cellulose-binding domain (CBD) of Bacillus subtilis BSE 616 endo-β-1,4-glucanase (Beg). The Cbg-CBD Beg fusion protein, 80 kDa, was expressed in Escherichia coli and immobilized to Avicel. Cellobiose was completely hydrolyzed with the immobilized fusion protein. The fusion protein bound to Avicel retained full activity during continuous operation for 24 h at 4°C. This revised version was published online in November 2006 with corrections to the Cover Date.  相似文献   
123.
The mTOR (mammalian or mechanistic Target of Rapamycin) is linked with oral cancer. Therefore, it is of interest to study the molecular docking-based binding of paclitaxel (a FDA approved drug for oral cancer) and its analogues with mTOR. Hence, we report the binding features of 10-Deacetyltaxol, 7-Epi-10-deacetyltaxol, 7-Epi-Taxol and 6alpha-Hydroxypaclitaxel with mTOR for further consideration.  相似文献   
124.
Experimental samples are valuable and can represent a significant investment in time and resources. It is highly desirable at times to obtain as much information as possible from a single sample. This is especially relevant for systems biology approaches in which several ‘omics platforms are studied simultaneously. Unfortunately, each platform has a particular extraction methodology which increases sample number and sample volume requirements when multiple ‘omics are analyzed. We evaluated the integration of a yeast extraction method; specifically we explored whether fractions from a single metabolite extraction could be apportioned to multiple downstream ‘omics analytical platforms. In addition, we examined how variations to a chloroform/methanol yeast metabolite extraction regime influence metabolite recoveries. We show that protein suitable for proteomic analysis can be recovered from a metabolite extraction and that recovery of lipids, while reproducible, are not wholly quantitative. Higher quenching solution temperatures (?30 °C) can be used without significant leakage of intracellular metabolites when lower fermentation temperatures (20 °C) are employed. However, extended residence time in quenching solution, in combination with vigorous washing of quenched cell pellets, leads to extensive leakage of intracellular metabolites. Finally, there is minimal difference in metabolite amounts obtained when metabolite extractions are performed at 4 °C compared to extractions at ?20 °C. The evaluated extraction method delivers material suitable for metabolomic and proteomic analyses from the same sample preparation.  相似文献   
125.
The design and synthesis of a small library of 8-amidoflavone, 8-sulfonamidoflavone, 8-amido-7-hydroxyflavone, and heterocyclic analogues of flavopiridol is reported. The potential activity of these compounds as kinase inhibitors was evaluated by cytotoxicity studies in MCF-7 and ID-8 cancer cell lines and inhibition of CDK2-Cyclin A enzyme activity in vitro. The antiproliferative and CDK2-Cyclin A inhibitory activity of these analogues was significantly lower than the activity of flavopiridol. Molecular docking simulations were carried out and these studies suggested a different binding orientation inside the CDK2 binding pocket for these analogues compared to flavopiridol.  相似文献   
126.
127.

Background

Although cesarean delivery and prenatal exposure to antibiotics are likely to affect the gut microbiome in infancy, their effect on the development of atopic dermatitis (AD) in infancy is unclear. The influence of individual genotypes on these relationships is also unclear. To evaluate with a prospective birth cohort study whether cesarean section, prenatal exposure to antibiotics, and susceptible genotypes act additively to promote the development of AD in infancy.

Methods

The Cohort for Childhood of Asthma and Allergic Diseases (COCOA) was selected from the general Korean population. A pediatric allergist assessed 412 infants for the presence of AD at 1 year of age. Their cord blood DNA was subjected to interleukin (IL)-13 (rs20541) and cluster-of-differentiation (CD)14 (rs2569190) genotype analysis.

Results

The combination of cesarean delivery and prenatal exposure to antibiotics associated significantly and positively with AD (adjusted odds ratio, 5.70; 95% CI, 1.19–27.3). The association between cesarean delivery and AD was significantly modified by parental history of allergic diseases or risk-associated IL-13 (rs20541) and CD14 (rs2569190) genotypes. There was a trend of interaction between IL-13 (rs20541) and delivery mode with respect to the subsequent risk of AD. (P for interaction = 0.039) Infants who were exposed prenatally to antibiotics and were born by cesarean delivery had a lower total microbiota diversity in stool samples at 6 months of age than the control group. As the number of these risk factors increased, the AD risk rose (trend p<0.05).

Conclusion

Cesarean delivery and prenatal antibiotic exposure may affect the gut microbiota, which may in turn influence the risk of AD in infants. These relationships may be shaped by the genetic predisposition.  相似文献   
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129.
A number of compounds from different chemical classes are known to bind competitively to the ATP-pocket of Hsp90 and inhibit its chaperone function. The natural product geldanamycin was the first reported inhibitor of Hsp90 and since then synthetic inhibitors from purine, isoxazole and indazol-4-one chemical classes have been discovered and are currently or soon to be in clinical trials for the treatment of cancer. In spite of a similar binding mode to Hsp90, distinct biological profiles were demonstrated among these molecules, both in vitro and in vivo. To better understand the molecular basis for these dissimilarities, we report here the synthesis of chemical tools for three Hsp90 inhibitor classes. These agents will be useful for probing tumor-by-tumor the Hsp90 complexes isolated by specific inhibitors. Such information will lead to better understanding of tumor specific molecular markers to aid in their clinical development. It will also help to elucidate the molecular basis for the biological differences observed among Hsp90 inhibitors.  相似文献   
130.
Membrane-type-1 Matrix Metalloproteinase (MT1-MMP) is a multifunctional protease that regulates ECM degradation, proMMP-2 activation, and varied cellular processes including migration and viability. MT1-MMP is believed to be a central mediator of tumourigenesis whose role is dictated by its functionally distinct protein domains. Both the localization and signal transduction capabilities of MT1-MMP are dependent on its cytoplasmic domain, exemplifying diverse regulatory functions. To further our understanding of the multifunctional contributions of MT1-MMP to cellular processes, we overexpressed cytoplasmic domain altered constructs in MCF-7 breast cancer cells and analyzed migration and viability in 2D culture conditions, morphology in 3D Matrigel culture, and tumorigenic ability in vivo. We found that the cytoplasmic domain was not needed for MT1-MMP mediated migration promotion, but was necessary to maintain viability during serum depravation in 2D culture. Similarly, during 3D Matrigel culture the cytoplasmic domain of MT1-MMP was not needed to initiate a protrusive phenotype, but was necessary to prevent colony blebbing when cells were serum deprived. We also tested in vivo tumorigenic potential to show that cells expressing cytoplasmic domain altered constructs demonstrated a reduced ability to vascularize tumours. These results suggest that the cytoplasmic domain regulates MT1-MMP function in a manner required for cell survival, but is dispensable for cell migration.  相似文献   
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