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1.
To examine the localization of von Hippel–Lindau (VHL) protein in human tissues, we produced four novel monoclonal antibodies against human VHL protein. Western blot analysis revealed that two of these antibodies recognized the epitope in amino acid sequence 60–89 of the VHL protein and the others recognized sequences 54–60 and 189–213. In a wild-type VHL gene-transfected cell line, immunocytochemistry and immunoelectron microscopy demonstrated the intracytoplasmic localization of VHL protein, particularly in mitotic cells. In normal human tissues, VHL protein was detected immunohistochemically in epithelial cells covering the body surface and the alimentary, respiratory, and genitourinary tracts; in secretory epithelial cells of exocrine and endocrine organs; in parenchymal cells of visceral organs; in cardiomyocytes; in neurons in nervous tissue; in lymphocytes in lymphoid tissue; and in macrophages. In pathological specimens, VHL protein was expressed in VHL-related tumor, as well as in endothelial cells, fibroblasts, and pericytes, all of which are involved in active angiogenesis. These findings suggest that these monoclonal antibodies can be useful for various immunological assays and that the VHL protein plays fundamental roles in physiological and pathological situations, especially in neovascularization.  相似文献   

2.
Ernoult-Lange M  Bénard M  Kress M  Weil D 《Biochimie》2012,94(7):1572-1577
Micro-RNAs (miRNAs) are major actors of RNA interference (RNAi), a regulation pathway which leads to translational repression and/or degradation of specific mRNAs. They provide target specificity by incorporating into the RISC complex and guiding its binding to mRNA. Since the discovery of RNAi, many progresses have been made on the mechanism of action of the RISC complex and on the identification of target mRNAs. However, the regulation of RNAi has been poorly investigated so far. Recently, various studies have revealed physical and functional relationships between RNAi, P-bodies and mitochondria. This review intends to recapitulate these data and discuss their potential importance in cell metabolism.  相似文献   

3.
Gao H  He X  Wu M  Zhang Z  Wang D  Lv L  Su Z  Huang Y 《The protein journal》2011,30(2):138-142
Hirschsprung’s disease (HSCR) is the most common identifiable developmental disorder of the enteric nervous system. The present study was designed to analyze the differential proteomic patterns in stenotic colon segment tissues from patients with HSCR. We analyzed 20 paired stenotic and normal colon segment tissues from patients with HSCR, and identified 13 proteins from stenotic segment tissues peptide fingerprint mapping and SELDI MS that were separated using 2-DE. The protein levels of four selected proteins (α-actinin-4, ACTN4; myosin regulatory light chain interacting protein, MYLIP; fatty acid binding protein 7, FABP7; bone morphogenetic protein receptor type 1A, BMPR1A) were further validated by Western blot analysis. This study, investigating for the first time proteomic changes in stenotic colon segment tissues from patients with HSCR, provides potential markers or promising new candidate actors for the pathogenesis of HSCR.  相似文献   

4.
《Free radical research》2013,47(6):323-327
Breath analysis is a non-invasive method for investigation of the volatile compounds produced by humans. Pentane has often been taken as an indicator of lipid peroxidation. Our purpose in this study was to determine its normal concentration in the breath of healthy humans. Using a specific and sensitive gas chromatography-mass spectrometry technique pentane concentrations in breath were lower than 10 pmoles/1. The high levels of pentane found by some authors in healthy humans were probably due to the coelution of pentane with isoprene, a volatile hydrocarbon present in human breath.  相似文献   

5.
Is Pentane a Normal Constituent of Human Breath?   总被引:1,自引:0,他引:1  
Breath analysis is a non-invasive method for investigation of the volatile compounds produced by humans. Pentane has often been taken as an indicator of lipid peroxidation. Our purpose in this study was to determine its normal concentration in the breath of healthy humans. Using a specific and sensitive gas chromatography-mass spectrometry technique pentane concentrations in breath were lower than 10 pmoles/1. The high levels of pentane found by some authors in healthy humans were probably due to the coelution of pentane with isoprene, a volatile hydrocarbon present in human breath.  相似文献   

6.

Background

To date, few parameters have been found that can aid in patient selection and surgical strategy for eloquent area gliomas.

Aims

The aim of the study was to analyze preoperative and intraoperative factors that can predict functional outcome and extent of resection in eloquent area tumors.

Patients and Methods

A retrospective analysis was conducted on 60 patients harboring supratentorial gliomas in eloquent areas undergoing awake surgery. The analysis considered clinical, neuroradiologic (morphologic), intraoperative, and postoperative factors. End-points were extent of resection (EOR) as well as functional short- and long-term outcome. Postoperatively, MRI objectively established the EOR. χ2 analyses were used to evaluate parameters that could be predictive. Multivariate logistic regression analyses were used to evaluate the best combination to predict binary positive outcomes.

Results

In 90% of the cases, subcortical stimulation was positive in the margins of the surgical cavity. Postoperatively, 51% of the patients deteriorated but 90% of the patients regained their preoperative neurological score. Factors negatively affecting EOR were volume, degree of subcortical infiltration, and presence of paresis (P<0.01). Sharp margins and cystic components were more amenable to gross total resection (P<0.01). Contrast enhancement (P<0.02), higher grade (P<0.01), paresis (P<0.01), and residual tumor in the cortex (P<0.02) negatively affected long-term functional outcomes, whereas postoperative deterioration could not be predicted for any factor other than paresis. Subcortical stimulation did not correlate with deterioration, both postoperatively (P<0.08) and at follow-up (P<0.042).

Conclusions

Biological and morphological factors such as type of margins, volume, preoperative neurological status, cystic components, histology and the type of infiltration into the white matter must be considered when planning intraoperative mapping.  相似文献   

7.
Honey bee colonies are highly dependent upon the availability of floral resources from which they get the nutrients (notably pollen) necessary to their development and survival. However, foraging areas are currently affected by the intensification of agriculture and landscape alteration. Bees are therefore confronted to disparities in time and space of floral resource abundance, type and diversity, which might provide inadequate nutrition and endanger colonies. The beneficial influence of pollen availability on bee health is well-established but whether quality and diversity of pollen diets can modify bee health remains largely unknown. We therefore tested the influence of pollen diet quality (different monofloral pollens) and diversity (polyfloral pollen diet) on the physiology of young nurse bees, which have a distinct nutritional physiology (e.g. hypopharyngeal gland development and vitellogenin level), and on the tolerance to the microsporidian parasite Nosema ceranae by measuring bee survival and the activity of different enzymes potentially involved in bee health and defense response (glutathione-S-transferase (detoxification), phenoloxidase (immunity) and alkaline phosphatase (metabolism)). We found that both nurse bee physiology and the tolerance to the parasite were affected by pollen quality. Pollen diet diversity had no effect on the nurse bee physiology and the survival of healthy bees. However, when parasitized, bees fed with the polyfloral blend lived longer than bees fed with monofloral pollens, excepted for the protein-richest monofloral pollen. Furthermore, the survival was positively correlated to alkaline phosphatase activity in healthy bees and to phenoloxydase activities in infected bees. Our results support the idea that both the quality and diversity (in a specific context) of pollen can shape bee physiology and might help to better understand the influence of agriculture and land-use intensification on bee nutrition and health.  相似文献   

8.
The objective of the present study was to investigate the effects of processing variables and formulation factors on the characteristics of hot-melt extrudates containing a copolymer (Kollidon® VA 64). Nifedipine was used as a model drug in all of the extrudates. Differential scanning calorimetry (DSC) was utilized on the physical mixtures and melts of varying drug–polymer concentrations to study their miscibility. The drug–polymer binary mixtures were studied for powder flow, drug release, and physical and chemical stabilities. The effects of moisture absorption on the content uniformity of the extrudates were also studied. Processing the materials at lower barrel temperatures (115–135°C) and higher screw speeds (50–100 rpm) exhibited higher post-processing drug content (~99–100%). DSC and X-ray diffraction studies confirmed that melt extrusion of drug–polymer mixtures led to the formation of solid dispersions. Interestingly, the extrusion process also enhanced the powder flow characteristics, which occurred irrespective of the drug load (up to 40% w/w). Moreover, the content uniformity of the extrudates, unlike the physical mixtures, was not sensitive to the amount of moisture absorbed. The extrusion conditions did not influence drug release from the extrudates; however, release was greatly affected by the drug loading. Additionally, the drug release from the physical mixture of nifedipine–Kollidon® VA 64 was significantly different when compared to the corresponding extrudates (f2 = 36.70). The extrudates exhibited both physical and chemical stabilities throughout the period of study. Overall, hot-melt extrusion technology in combination with Kollidon® VA 64 produced extrudates capable of higher drug loading, with enhanced flow characteristics, and excellent stability.KEY WORDS: extrusion, Kollidon® VA 64, moisture absorption, nifedipine, solid dispersion  相似文献   

9.
The purpose of this study was to investigate the combined influence of three-level, three-factor variables on the formulation of dacarbazine (a water-soluble drug) loaded cubosomes. Box–Behnken design was used to obtain a second-order polynomial equation with interaction terms to predict response values. In this study, the selected and coded variables X 1, X 2, and X 3 representing the amount of monoolein, polymer, and drug as the independent variables, respectively. Fifteen runs of experiments were conducted, and the particle size (Y 1) and encapsulation efficiency (Y 2) were evaluated as dependent variables. We performed multiple regression to establish a full-model second-order polynomial equation relating independent and dependent variables. A second-order polynomial regression model was constructed for Y 1 and confirmed by performing checkpoint analysis. The optimization process and Pareto charts were obtained automatically, and they predicted the levels of independent coded variables X 1, X 2, and X 3 (−1, 0.53485, and −1, respectively) and minimized Y 1 while maximizing Y 2. These corresponded to a cubosome formulation made from 100 mg of monoolein, 107 mg of polymer, and 2 mg with average diameter of 104.7 nm and an encapsulation efficiency of 6.9%. The Box–Behnken design proved to be a useful tool to optimize the particle size of these drug-loaded cubosomes. For encapsulation efficiency (Y 2), further studies are needed to identify appropriate regression model.  相似文献   

10.
Human osteoclast-stimulating factor (hOSF) is an intracellular protein produced by osteoclasts that induces osteoclast formation and bone resorption in osteoporosis by recruiting multiple signaling complexes with its diverse biological partners through peptide-mediated interactions (PMIs). The protein contains a modular peptide-recognition domain of Src homology 3 (SH3), which can recognize and bind to the polyproline regions of its partner proteins, as well as two N-terminal polyproline segments, which can be recognized and bound by the SH3 domains of its partner proteins. Here, we attempted to elucidate the complicated PMIs between the different SH3 domains and different polyprolines of hOSF and its three known interacting partners, i.e. proto-oncogene tyrosine-protein kinase (c-Src), survival motor neuron (SMN) and Src-associated in mitosis, 68 kD (Sam68). A total of 29 peptide segments containing the SH3-binding motif PXXP were extracted from these partner proteins, which are potential binding sites of hOSF SH3 domain, while the c-Src kinase also possesses a SH3 domain that may recognize and bind the two polyproline peptides at hOSF N-terminus. Structural bioinformatics analysis identified a number of biologically functional PMI candidates between these SH3 domains and these polyproline peptides, which were then tested in vitro using fluorescence spectroscopy assays. Consequently, it is found that (i) hOSF SH3 domain exhibits strong binding potency to two Sam68 peptides 36RQPPLPHR43 (K d = 13.7 μM) and 425APPARPVK432 (K d = 3.2 μM) as well as moderate affinity to three SMN peptides 193FLPPPPPM200 (K d = 56.2 μM), 235PFPSGPPI242 (K d = 28.4 μM) and 246PPPICPDS253 (K d = 74.5 μM), but has only weak or no binding to c-Src peptides. Instead, a proline-rich region at hOSF N-terminal that contains two overlapping peptides (3KPPPKPVK10 and 6PKPVKPGQ13) can be bound tightly by c-Src SH3 domain with high and moderate affinity (K d = 5.8 and 39.6 μM, respectively).  相似文献   

11.
12.
《Anthrozo?s》2013,26(3):341-355
ABSTRACT

This article examines human–animal relations in animism. Ethnographies of indigenous peoples in the Americas, Asia, and Africa are compared in order to provide a basic sketch of the remarkable consistency of animism across the world. A central feature that recurs time and again is the positional quality of life and death. That is, life and death are not conceived of as inherent properties but as changeable positions. This is why indigenous hunters, shamans, and diviners temporarily “die” when they participate in the specific rites or cults associated with their respective endeavors. Such metamorphoses of the living into the dead are crucial to understand how hunters engage with their prey, shamans mobilize their animal-helpers, and honey collectors approach their bees. At the same time, these different activities involve the transformation of humans into animals. Chachi bird stalkers and Uduk antelope hunters identify themselves with their quarry, Navajo medicine men and Ainu shamans shape-change into their animallike adversaries, while Batek mourners may adopt a tiger-form. At first sight, such simultaneous metamorphoses (from the living into the dead and from humans into animals) may seem contradictory. Yet, this apparent inconsistency disappears if one realizes that the modern notion of wildlife cannot be applied to animism. I show that the monkeys, deer, whales, tigers, and elephants that indigenous hunters and shamans deal with must be understood as “wild-dead” rather than as wildlife. These various animals are palpable representatives of an expanded realm of death which—I suggest—is characteristic of all forms of animism. In this context, being animate is not sufficient to be considered “alive.”  相似文献   

13.
14.
15.
Quality control (QC) in the endoplasmic reticulum (ER) scrutinizes newly synthesized proteins and directs them either to ER export or ER-associated degradation (ERAD). Here, we demonstrate that the human δ-opioid receptor (hδOR) is subjected to ERQC in both N-glycan-dependent and -independent manners. This was shown by investigating the biosynthesis and trafficking of wild-type and non-N-glycosylated F27C variants in metabolic pulse-chase assays coupled with flow cytometry and cell surface biotinylation. Both QC mechanisms distinguished the minute one-amino acid difference between the variants, targeting a large fraction of hδOR-Cys27 to ERAD. However, the N-glycan-independent QC was unable to compensate the N-glycan-dependent pathway, and some incompletely folded non-N-glycosylated hδOR-Cys27 reached the cell surface in conformation incompatible with ligand binding. The turnover of receptors associating with the molecular chaperone calnexin (CNX) was significantly slower for the hδOR-Cys27, pointing to an important role of CNX in the hδOR N-glycan-dependent QC. This was further supported by the fact that inhibiting the co-translational interaction of hδOR-Cys27 precursors with CNX led to their ERAD. Opioid receptor pharmacological chaperones released the CNX-bound receptors to ER export and, furthermore, were able to rescue the Cys27 variant from polyubiquitination and retrotranslocation to the cytosol whether carrying N-glycans or not. Taken together, the hδOR appears to rely primarily on the CNX-mediated N-glycan-dependent QC that has the capacity to assist in folding, whereas the N-glycan-independent mechanism constitutes an alternative, although less accurate, system for directing misfolded/incompletely folded receptors to ERAD, possibly in altered cellular conditions.  相似文献   

16.
The cell surface glycoprotein γ-glutamyl transpeptidase (GGT) was isolated from healthy human kidney and liver to characterize its glycosylation in normal human tissue in vivo. GGT is expressed by a single cell type in the kidney. The spectrum of N-glycans released from kidney GGT constituted a subset of the N-glycans identified from renal membrane glycoproteins. Recent advances in mass spectrometry enabled us to identify the microheterogeneity and relative abundance of glycans on specific glycopeptides and revealed a broader spectrum of glycans than was observed among glycans enzymatically released from isolated GGT. A total of 36 glycan compositions, with 40 unique structures, were identified by site-specific glycan analysis. Up to 15 different glycans were observed at a single site, with site-specific variation in glycan composition. N-Glycans released from liver membrane glycoproteins included many glycans also identified in the kidney. However, analysis of hepatic GGT glycopeptides revealed 11 glycan compositions, with 12 unique structures, none of which were observed on kidney GGT. No variation in glycosylation was observed among multiple kidney and liver donors. Two glycosylation sites on renal GGT were modified exclusively by neutral glycans. In silico modeling of GGT predicts that these two glycans are located in clefts on the surface of the protein facing the cell membrane, and their synthesis may be subject to steric constraints. This is the first analysis at the level of individual glycopeptides of a human glycoprotein produced by two different tissues in vivo and provides novel insights into tissue-specific and site-specific glycosylation in normal human tissues.  相似文献   

17.

Background

Burden of disease estimates are widely used for priority setting in public health and disability-adjusted life years are a powerful “currency” nowadays. However, disability weights, which capture the disability incurred by a typical patient of a certain condition, are fundamental to such burden calculation and their determination remains a widely debated issue.

Methodology

A cross-sectional epidemiological survey was conducted in the recently established Taabo health demographic surveillance system (HDSS) in south-central Côte d''Ivoire, to provide new, population-based evidence on the disability caused by schistosomiasis and soil-transmitted helminthiasis. Parasitological results from stool, urine, and blood examinations were juxtaposed to quality of life (QoL) questionnaire results from 187 adults. A multivariable linear regression model with stepwise backward elimination was used to identify significant associations, considering also sociodemographic characteristics obtained from the Taabo HDSS database.

Principal Findings

Prevalences for hookworm, Plasmodium spp., Trichuris trichiura, Schistosoma haematobium and Schistosoma mansoni were 39.0%, 18.2%, 2.7%, 2.1% and 2.1%, respectively. S. mansoni and T. trichiura infections of any intensity reduced the participants'' self-rated QoL by 16 points (95% confidence interval (CI): 4–29 points) and 13 points (95% CI: 1–24 points), respectively, on a scale from 0 (worst QoL) to 100 points (best QoL). The only other statistically significant effect was a 1-point (95% CI: 0.1–2 points) increase on the QoL scale per one unit increase in a calculated wealth index.

Conclusions/Significance

We found consistent and significant results on the negative effects of schistosomiasis and soil-transmitted helminthiasis on adults'' self-rated QoL, also when taking sociodemographic characteristics into account. Our results warrant further investigation on the disability incurred by helmintic infections and the usefulness of generic QoL questionnaires in this endeavor.  相似文献   

18.
The choice of the type of abdominal incision performed in caesarean delivery is made chiefly on the basis of the individual surgeon’s experience and preference. A general consensus on the most appropriate surgical technique has not yet been reached. The aim of this systematic review of the literature is to compare the two most commonly used transverse abdominal incisions for caesarean delivery, the Pfannenstiel incision and the modified Joel-Cohen incision, in terms of acute and chronic post-surgical pain and their subsequent influence in terms of quality of life. Electronic database searches formed the basis of the literature search and the following databases were searched in the time frame between January 1997 and December 2013: MEDLINE, EMBASE Sciencedirect and the Cochrane Library. Key search terms included: “acute pain”, “chronic pain”, “Pfannenstiel incision”, “Misgav-Ladach”, “Joel Cohen incision”, in combination with “Caesarean Section”, “abdominal incision”, “numbness”, “neuropathic pain” and “nerve entrapment”. Data on 4771 patients who underwent caesarean section (CS) was collected with regards to the relation between surgical techniques and postoperative outcomes defined as acute or chronic pain and future pregnancy desire. The Misgav-Ladach incision was associated with a significant advantage in terms of reduction of post-surgical acute and chronic pain. It was indicated as the optimal technique in view of its characteristic of reducing lower pelvic discomfort and pain, thus improving quality of life and future fertility desire. Further studies which are not subject to important bias like pre-existing chronic pain, non-standardized analgesia administration, variable length of skin incision and previous abdominal surgery are required.  相似文献   

19.
Invertase (β-d-fructofuranoside fructohydrolase-E.C. 3.2.1.26) is a sucrose hydrolyzing enzyme found in microbial, plant and animal sources. Invertase from Candida utilis is a dimeric glycoprotein composed of two identical monomer subunits with an apparent molecular mass of 150 kDa. We investigated the mechanism of stabilization of invertase with polyols (glycerol, xylitol, and sorbitol). Activity, thermodynamic and kinetic measurements of invertase were performed as a function of polyol concentration and showed that polyols act as very effective stabilizing agents. The result from the solvent-invertase interaction shows preferential exclusion of the polyols from the protein domain leading to preferential hydration of protein. Apparent thermal denaturation temperature of the protein (T m ) rose from 75 °C to a maximum of 85 °C in 30% glycerol. The stabilization has been attributed to the preferential hydration of the enzyme.  相似文献   

20.
Immunohistochemical distribution of laminin γ 2 chain, a subunit of the basement membrane protein laminin-5, was examined in 19 cases of human embryos and foetuses ranging from 4 to 25 weeks of gestation. Laminin γ 2 was first detected in the basement membranes underlying ectodermal epithelial tissues, such as the skin and tooth, as early as 5–6 weeks of gestation. Between 6–7 and 12–13 weeks, laminin γ 2 was detected in the basement membranes of various endodermal epithelial tissues, such as the bronchus, oesophagus, stomach, intestines, urinary bladder, gallbladder and hepatopancreatic duct. The deposition of laminin γ 2 in basement membrane was associated with the process of morphogenesis. In the small intestine, laminin γ 2 first appeared in the basement membrane of the primitive short villi, and its level gradually increased in the villus region but decreased in the cryptic region during the maturation of the organ. In addition, non-basement membrane immunoreactivity for laminin γ 2 was detected in some mesoderm-derived tissues, such as the cartilage and skeletal and smooth muscle fibres. These results suggest a common role of laminin-5 and some specific roles of its γ 2 chain in the morphogenesis of human tissues.  相似文献   

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