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91.

Background

The current study evaluated the association between tea consumption and head and neck cancer (HNC) in Taiwan, where tea is a major agricultural product and a popular beverage.

Methods

Interviews regarding tea consumption (frequency, duration, and types) were conducted with 396 HNC cases and 413 controls. Unconditional logistic regression was performed to estimate the odds ratio (OR) and 95% confidence interval (CI) of HNC risk associated with tea drinking, adjusted for sex, age, education, cigarette smoking, betel quid chewing, and alcohol drinking.

Results

A reduced HNC risk associated with tea drinking (OR for every cup per day = 0.96, 95% CI: 0.93–0.99; OR for ≧5 cups per day = 0.60, 95% CI: 0.39–0.94) was observed. The association was especially significant for pharyngeal cancer (OR for every cup per day = 0.93, 95% CI: 0.88–0.98; OR for ≧5 cups per day = 0.32, 95% CI: 0.16–0.66). A significant inverse association between HNC and tea consumption was observed particularly for green tea.

Conclusions

This study suggests that tea drinking may reduce the risk of HNC. The anticancer property of tea, if proven, may offer a natural chemopreventive measure to reduce the occurrence of HNC.  相似文献   
92.

Purpose

To investigate the performance of hematoma shape, hematoma size, Glasgow coma scale (GCS) score, and intracerebral hematoma (ICH) score in predicting the 30-day mortality for ICH patients. To examine the influence of the estimation error of hematoma size on the prediction of 30-day mortality.

Materials and Methods

This retrospective study, approved by a local institutional review board with written informed consent waived, recruited 106 patients diagnosed as ICH by non-enhanced computed tomography study. The hemorrhagic shape, hematoma size measured by computer-assisted volumetric analysis (CAVA) and estimated by ABC/2 formula, ICH score and GCS score was examined. The predicting performance of 30-day mortality of the aforementioned variables was evaluated. Statistical analysis was performed using Kolmogorov-Smirnov tests, paired t test, nonparametric test, linear regression analysis, and binary logistic regression. The receiver operating characteristics curves were plotted and areas under curve (AUC) were calculated for 30-day mortality. A P value less than 0.05 was considered as statistically significant.

Results

The overall 30-day mortality rate was 15.1% of ICH patients. The hematoma shape, hematoma size, ICH score, and GCS score all significantly predict the 30-day mortality for ICH patients, with an AUC of 0.692 (P = 0.0018), 0.715 (P = 0.0008) (by ABC/2) to 0.738 (P = 0.0002) (by CAVA), 0.877 (P<0.0001) (by ABC/2) to 0.882 (P<0.0001) (by CAVA), and 0.912 (P<0.0001), respectively.

Conclusion

Our study shows that hematoma shape, hematoma size, ICH scores and GCS score all significantly predict the 30-day mortality in an increasing order of AUC. The effect of overestimation of hematoma size by ABC/2 formula in predicting the 30-day mortality could be remedied by using ICH score.  相似文献   
93.
We assessed the accuracy of species-level identification of two commercially available matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) systems (Bruker Biotyper and Vitek MS) and two conventional phenotypic methods (Phoenix 100 YBC and Vitek 2 Yeast ID) with that of rDNA gene sequencing analysis among 200 clinical isolates of commonly encountered yeasts. The correct identification rates of the 200 yeast isolates to species or complex (Candida parapsilosis complex, C. guilliermondii complex and C. rugosa complex) levels by the Bruker Biotyper, Vitek MS (using in vitro devices [IVD] database), Phoenix 100 YBC and Vitek 2 Yeast ID (Sabouraud''s dextrose agar) systems were 92.5%, 79.5%, 89%, and 74%, respectively. An additional 72 isolates of C. parapsilosis complex and 18 from the above 200 isolates (30 in each of C. parapsilosis, C. metapsilosis, and C. orthopsilosis) were also evaluated separately. Bruker Biotyper system could accurately identify all C. parapsilosis complex to species level. Using Vitek 2 MS (IVD) system, all C. parapsilosis but none of C. metapsilosis, or C. orthopsilosis could be accurately identified. Among the 89 yeasts misidentified by the Vitek 2 MS (IVD) system, 39 (43.8%), including 27 C. orthopsilosis isolates, could be correctly identified Using the Vitek MS Plus SARAMIS database for research use only. This resulted in an increase in the rate of correct identification of all yeast isolates (87.5%) by Vitek 2 MS. The two species in C. guilliermondii complex (C. guilliermondii and C. fermentati) isolates were correctly identified by cluster analysis of spectra generated by the Bruker Biotyper system. Based on the results obtained in the current study, MALDI-TOF MS systems present a promising alternative for the routine identification of yeast species, including clinically commonly and rarely encountered yeast species and several species belonging to C. parapsilosis complex, C. guilliermondii complex, and C. rugosa complex.  相似文献   
94.
Cancer patients frequently develop chemotherapy-induced peripheral neuropathy (CIPN), a painful and long-lasting disorder with profound somatosensory deficits. There are no effective therapies to prevent or treat this disorder. Pathologically, CIPN is characterized by a “dying-back” axonopathy that begins at intra-epidermal nerve terminals of sensory neurons and progresses in a retrograde fashion. Calcium dysregulation constitutes a critical event in CIPN, but it is not known how chemotherapies such as paclitaxel alter intra-axonal calcium and cause degeneration. Here, we demonstrate that paclitaxel triggers Sarm1-dependent cADPR production in distal axons, promoting intra-axonal calcium flux from both intracellular and extracellular calcium stores. Genetic or pharmacologic antagonists of cADPR signaling prevent paclitaxel-induced axon degeneration and allodynia symptoms, without mitigating the anti-neoplastic efficacy of paclitaxel. Our data demonstrate that cADPR is a calcium-modulating factor that promotes paclitaxel-induced axon degeneration and suggest that targeting cADPR signaling provides a potential therapeutic approach for treating paclitaxel-induced peripheral neuropathy (PIPN).  相似文献   
95.
Serum PAF acetylhydrolase increases during neonatal maturation   总被引:5,自引:0,他引:5  
Acetylhydrolase is an acid-labile, 43 kd protein that catalyzes the degradation of platelet activating factor (PAF), a potent phospholipid inflammatory mediator, to its biologically inactive metabolite lysoPAF. PAF has a short half-life, thus acetylhydrolase plays an important role in its regulation. Since previous work suggests that PAF may be involved in certain neonatal diseases such as necrotizing enterocolitis, we studied the effect of age on acetylhydrolase activity. Serum acetylhydrolase activity was quantified using radio-labelled PAF and measuring reaction products. Serum samples were obtained prospectively from 70 subjects ranging in age from 4 hr to 48 yr. Acetylhydrolase activity was lower for newborns (less than 3 wk) than all other age ranges (8.2 +/- 1.4 nmole/ml/min vs 30.0 +/- 1.6 nmole/ml/min, p less than .01). Furthermore, enzyme activity increased linearly with respect to the natural logarithm of age from 0 days to 6 weeks (r = 0.65, p less than .001). By 6 weeks of life acetylhydrolase activity approached values of older children and adults. Newborn acetylhydrolase activity was similar between term and preterm infants (8.6 +/- 1.9 nmole/ml/min vs 7.2 +/- 2.4 nmole/ml/min, p = NS). We conclude that acetylhydrolase activity is low in human neonates and increases during the first 6 weeks of life. These results suggest that newborn infants may be at increased risk for pathophysiologic processes mediated by PAF.  相似文献   
96.
Vasoactive intestinal peptide (VIP) and VIPergic nerve fibers are present in the ovaries of several mammalian species, suggesting a possible ovarian action of VIP. We have investigated the direct effects of synthetic porcine VIP on rat granulosa cell steroidogenesis in vitro. The cells were obtained from immature, hypophysectomized, estrogen-primed rats, and cultured in a serum-free medium for 24 h in the absence or presence of varying amounts of VIP. Medium steroids were then determined by specific radioimmunoassay. Vasoactive intestinal peptide dose-dependently stimulated progesterone, 20 alpha-hydroxypregn-4-ene-3-one (20 alpha-OH-progesterone), and estrogen production with an approximate ED50 value of 3 X 10(-8) M. Maximum steroid production induced by VIP ranged from 15% to 28% of that seen with maximal follicle-stimulating hormone (FSH) stimulation. In contrast to the ability of FSH to induce luteinizing hormone (LH) receptor formation, treatment with VIP did not increase [125I]iodo-human chorionic gonadotropin (hCG) binding to granulosa cells. The ability of several gastrointestinal peptides, having 17-44% sequence identity to VIP, to stimulate granulosa cell steroidogenesis was also tested. The most closely related peptide, PHM-27 was less effective than VIP, and the least closely related, secretin and glucagon, were ineffective at 10(-6) M. Vasoactive intestinal peptide seems to act at least partly through cyclic 3',5'-adenosine monophosphate (cAMP)-dependent processes: addition of a phosphodiesterase inhibitor significantly potentiated the VIP stimulation of granulosa cell steroidogenesis, and VIP was capable of producing a dose- and time-dependent increase in both intracellular and medium cAMP levels. Vasoactive intestinal peptide stimulation of estrogen production seemed to be a result of increased aromatase activity. The increased progesterone production was associated with increased pregnenolone production, increased rate of conversion of pregnenolone to progesterone via 3 beta-hydroxysteroid dehydrogenase, and decreased metabolism of progesterone via 20 alpha-hydroxysteroid dehydrogenase. These results indicate that VIP exerts a specific action on granulosa cells to increase estrogen and progestin production. The observed direct effects of VIP, coupled with its identification in the ovary, suggest that VIP may be a physiologically important regulator of ovarian activity.  相似文献   
97.
98.
Observations on the renal processing and sorting of prorenin.   总被引:1,自引:0,他引:1  
Human prorenin is the biosynthetic precursor of renin. In general, prorenin is enzymatically inactive until it is converted to renin. The kidney is the major source of renin in the circulation, and is also an important source of circulating prorenin. The mechanisms of prorenin sorting and processing to renin in the juxtaglomerular cell may be a determinant of renal renin production. Therefore, our studies have focused on renal enzymes involved in "limited proteolysis" of prorenin to renin and on the morphology of prorenin sorting in the human juxtaglomerular cell.  相似文献   
99.
  • The Omp85 proteins form a large membrane protein family in bacteria and eukaryotes. Omp85 proteins are composed of a C‐terminal β‐barrel‐shaped membrane domain and one or more N‐terminal polypeptide transport‐associated (POTRA) domains. However, Arabidopsis thaliana contains two genes coding for Omp85 proteins without a POTRA domain. One gene is designated P39, according to the molecular weight of the encoded protein. The protein is targeted to plastids and it was established that p39 has electrophysiological properties similar to other Omp85 family members, particularly to that designated as Toc75V/Oep80.
  • We analysed expression of the gene and characterised two T‐DNA insertion mutants, focusing on alterations in photosynthetic activity, plastid ultrastructure, global expression profile and metabolome.
  • We observed pronounced expression of P39, especially in veins. Mutants of P39 show growth aberrations, reduced photosynthetic activity and changes in plastid ultrastructure, particularly in the leaf tip. Further, they display global alteration of gene expression and metabolite content in leaves of mature plants.
  • We conclude that the function of the plastid‐localised and vein‐specific Omp85 family protein p39 is important, but not essential, for maintenance of metabolic homeostasis of full‐grown A. thaliana plants. Further, the function of p39 in veins influences the functionality of other plant tissues. The link connecting p39 function with metabolic regulation in mature A. thaliana is discussed.
  相似文献   
100.
In plants, the mitogen‐activated protein kinase (MAPK) cascades are the central signaling pathways of the complicated defense network triggered by the perception of pathogen‐associated molecular patterns to repel pathogens. The Arabidopsis thaliana MAPK phosphatase 1 (AtMKP1) negatively regulates the activation of MAPKs. Recently, the AtMKP1 homolog of Nicotiana benthamiana (NbMKP1) was found in association with the Bamboo mosaic virus (BaMV) replication complex. This study aimed to investigate the role of NbMKP1 in BaMV multiplication in N. benthamiana. Silencing of NbMKP1 increased accumulations of the BaMV‐encoded proteins and the viral genomic RNA, although the same condition reduced the infectivity of Pseudomonas syringae pv. tomato DC3000 in N. benthamiana. On the other hand, overexpression of NbMKP1 decreased the BaMV coat protein accumulation in a phosphatase activity‐dependent manner in protoplasts. NbMKP1 also negatively affected the in vitro RNA polymerase activity of the BaMV replication complex. Collectively, the activity of NbMKP1 seems to reduce BaMV multiplication, inconsistent with the negatively regulatory role of MKP1 in MAPK cascades in terms of warding off fungal and bacterial invasion. In addition, silencing of NbMKP1 increased the accumulation of Foxtail mosaic virus but decreased Potato virus X. The discrepant effects exerted by NbMKP1 on different pathogens foresee the difficulty to develop plants with broad‐spectrum resistance through genetically manipulating a single player in MAPK cascades.  相似文献   
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