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81.
The platelet release reaction was studied by a new quenched-flow approach. Platelets labeled with 14C-serotonin were reacted for short times (up to 5 sec) with thrombin and then quenched with glutaraldehyde or paraformaldehyde. Serotonin secretion began within 1 sec and was nearly complete by 4 sec. Aggregation recorded by a resistive-particle counter was similarly fast. Therefore, the quenched-flow system reveals that serotonin secretion can occur more rapidly than estimated in earlier studies. 相似文献
82.
Andi Utama Sigit Purwantomo Marlinang Diarta Siburian Rama Dhenni Rino Alvani Gani Irsan Hasan Andri Sanityoso Upik Anderiani Miskad Fardah Akil Irawan Yusuf Wenny Astuti Achwan Soewignjo Soemohardjo Syafruddin AR Lelosutan Ruswhandi Martamala Benyamin Lukito Unggul Budihusodo Laurentius Adrianus Lesmana Ali Sulaiman Susan Tai 《World journal of gastroenterology : WJG》2009,15(32):4028-4036
AIM: To identify the distribution of hepatitis B virus (HBV) subgenotype and basal core promoter (BCP) mutations among patients with HBV-associated liver disease in Indonesia.
METHODS: Patients with chronic hepatitis (CH, n =61), liver cirrhosis (LC, n = 62), and hepatocellular carcinoma (HCC, n = 48) were included in this study. HBV subgenotype was identified based on S or preS gene sequence, and mutations in the HBx gene including the overlapping BCP region were examined by direct sequencing.
RESULTS: HBV genotype B (subgenotypes B2, B3, B4, 85 and B7) the major genotype in the samples, accounted for 75.4%, 71.0% and 75.0% of CH, LC and HCC patients, respectively, while the genotype C (subgenotypes C1, C2 and C3) was detected in 24.6%, 29.0%, and 25.0% of CH, LC, and HCC patients, respectively. Subgenotypes B3 (84.9%) and C1 (82.2%) were the main subgenotype in HBV genotype B and C, respectively. Serotype adw2 (84.9%) and adrq+ (89.4%) were the most prevalent in HBV genotype B and C, respectively. Double mutation (A1762T/G1764A) in the BCP was significantly higher in LC (59.7%) and HCC (54.2%) than in CH (19.7%), suggesting that this mutation was associated with severity of liver disease. The T1753V was also higher in LC (46.8%), but lower in HCC (22.9%) and CH (18.0%), suggesting that this mutation may be an indicator of cirrhosis.
CONCLUSION: HBV genotype B/B3 and C/C1 are the major genotypes in Indonesia. Mutations in BCP, such as A1762T/G1764A and T1753V, might have an association with manifestations of liver disease. 相似文献
METHODS: Patients with chronic hepatitis (CH, n =61), liver cirrhosis (LC, n = 62), and hepatocellular carcinoma (HCC, n = 48) were included in this study. HBV subgenotype was identified based on S or preS gene sequence, and mutations in the HBx gene including the overlapping BCP region were examined by direct sequencing.
RESULTS: HBV genotype B (subgenotypes B2, B3, B4, 85 and B7) the major genotype in the samples, accounted for 75.4%, 71.0% and 75.0% of CH, LC and HCC patients, respectively, while the genotype C (subgenotypes C1, C2 and C3) was detected in 24.6%, 29.0%, and 25.0% of CH, LC, and HCC patients, respectively. Subgenotypes B3 (84.9%) and C1 (82.2%) were the main subgenotype in HBV genotype B and C, respectively. Serotype adw2 (84.9%) and adrq+ (89.4%) were the most prevalent in HBV genotype B and C, respectively. Double mutation (A1762T/G1764A) in the BCP was significantly higher in LC (59.7%) and HCC (54.2%) than in CH (19.7%), suggesting that this mutation was associated with severity of liver disease. The T1753V was also higher in LC (46.8%), but lower in HCC (22.9%) and CH (18.0%), suggesting that this mutation may be an indicator of cirrhosis.
CONCLUSION: HBV genotype B/B3 and C/C1 are the major genotypes in Indonesia. Mutations in BCP, such as A1762T/G1764A and T1753V, might have an association with manifestations of liver disease. 相似文献
83.
G Zifarelli A Liantonio A Gradogna A Picollo G Gramegna M De Bellis AR Murgia E Babini D Conte Camerino M Pusch 《British journal of pharmacology》2010,160(7):1652-1661
Background and purpose:
ClC-K kidney Cl− channels are important for renal and inner ear transepithelial Cl− transport, and are potentially interesting pharmacological targets. They are modulated by niflumic acid (NFA), a non-steroidal anti-inflammatory drug, in a biphasic way: NFA activates ClC-Ka at low concentrations, but blocks the channel above ∼1 mM. We attempted to identify the amino acids involved in the activation of ClC-Ka by NFA.Experimental approach:
We used site-directed mutagenesis and two-electrode voltage clamp analysis of wild-type and mutant channels expressed in Xenopus oocytes. Guided by the crystal structure of a bacterial CLC homolog, we screened 97 ClC-Ka mutations for alterations of NFA effects.Key results:
Mutations of five residues significantly reduced the potentiating effect of NFA. Two of these (G167A and F213A) drastically altered general gating properties and are unlikely to be involved in NFA binding. The three remaining mutants (L155A, G345S and A349E) severely impaired or abolished NFA potentiation.Conclusions and implications:
The three key residues identified (L155, G345, A349) are localized in two different protein regions that, based on the crystal structure of bacterial CLC homologs, are expected to be exposed to the extracellular side of the channel, relatively close to each other, and are thus good candidates for being part of the potentiating NFA binding site. Alternatively, the protein region identified mediates conformational changes following NFA binding. Our results are an important step towards the development of ClC-Ka activators for treating Bartter syndrome types III and IV with residual channel activity. 相似文献84.
TG Bird L Boutler A Cole S Lorenzini WY Lu T Hay R Ridgway M Williams B Knight S Gordon Keylock D Wjotacha T Jamieson JP Iredale AR Clarke OJ Sansom SJ Forbes 《Lancet》2013
Insufficient regeneration of the adult liver is believed to cause failure to recover from severe liver disease. An undifferentiated cell population with stem-cell-like qualities known as hepatic progenitor cells (HPCs) is hypothesised to have a central role in regeneration of the adult liver during massive or chronic liver disease. Stem cells in other organ systems are believed to reside in a specialised microenvironment or niche that supports their maintenance and function. The existence of a hepatic stem cell niche might provide a means of therapeutically manipulating endogenous HPCs in vivo as a regenerative therapy.To investigate the physiological potential of HPCs to regenerate the mammalian liver, we have established a novel model of hepatocellular injury and HPC activation using genetic manipulation of hepatocytes. After hepatocyte senescence and death in this model (AhCre Mdm2flox), HPCs expand and bring about the complete regeneration of the liver parenchyma.We demonstrate that a stereotypical niche, consisting partly of macrophages, exists in both animal models and correlating human disease. Using cell tracking, we show active recruitment of extrahepatic macrophages into this niche during injury. In health, intravenous injection of macrophages results in macrophage engraftment to the liver niche, with subsequent HPC activation and changes to liver structure and function.Within the niche, macrophages use paracrine signalling to control both HPC proliferation and cell fate via TWEAK (tumour-necrosis-factor-like weak inducer of apoptosis) and the Wnt signalling pathway, respectively. After hepatocellular injury, macrophages ingest hepatocyte debris, and release Wnt which promotes HPC differentiation into hepatocytes. TWEAK is vital for HPC proliferation in the AhCre Mdm2flox model of regeneration. Here, the absence of TWEAK signalling results in liver failure and mortality.This work has demonstrated for the first time the ability of a solid organ to fully regenerate in the adult mammal from progenitor cells, and additionally highlights mechanisms by which this process can be modulated by either small molecule or cell therapy.FundingUniversity of Edinburgh. 相似文献
85.
R Alexander A Kerby AA Aubdool AR Power S Grover C Gentry AD Grant 《British journal of pharmacology》2013,168(3):761-772
Background and Purpose
The Ca2+-permeable cation channel TRPV4 is activated by mechanical disturbance of the cell membrane and is implicated in mechanical hyperalgesia. Nerve growth factor (NGF) is increased during inflammation and causes mechanical hyperalgesia. 4α-phorbol 12,13-didecanoate (4αPDD) has been described as a selective TRPV4 agonist. We investigated NGF-induced hyperalgesia in TRPV4 wild-type (+/+) and knockout (–/–) mice, and the increases in [Ca2+]i produced by 4αPDD in cultured mouse dorsal root ganglia neurons following exposure to NGF.Experimental Approach
Withdrawal thresholds to heat, von Frey hairs and pressure were measured in mice before and after systemic administration of NGF. Changes in intracellular Ca2+ concentration were measured by ratiometric imaging with Fura-2 in cultured DRG and trigeminal ganglia (TG) neurons during perfusion of TRPV4 agonists.Key Results
Administration of NGF caused a significant sensitization to heat and von Frey stimuli in TRPV4 +/+ and –/– mice, but only TRPV4 +/+ mice showed sensitization to noxious pressure. 4αPDD stimulated a dose-dependent increase in [Ca2+]i in neurons from +/+ and –/– mice, with the proportion of responding neurons and magnitude of increase unaffected by the genotype. In contrast, the selective TRPV4 agonist GSK1016790A failed to stimulate an increase in intracellular Ca2+ in cultured neurons. Responses to 4αPDD were unaffected by pretreatment with NGF.Conclusions and Implications
TRPV4 contributes to mechanosensation in vivo, but there is little evidence for functional TRPV4 in cultured DRG and TG neurons. We conclude that 4αPDD activates these neurons independently of TRPV4, so it is not appropriate to refer to 4αPDD as a selective TRPV4 agonist. 相似文献86.
Axel R. von Müller Cristina B. López Aldo R. Eynard Carlos A. Guzmán 《Drug and chemical toxicology》2013,36(4):307-311
Brea gum is a phloematic exudate from Parkinsonia praecox, an autoctonous tree that grows in the arid areas of Argentina. In this work, we propose its potential as a food additive. However, as no toxicological safety evaluation of brea gum has yet been reported, this preliminary study was conducted to evaluate its long-term toxicity over a 120-day period in BALB/c mice fed with brea gum at various levels in the diet. The results showed that animals on diets containing up to 5% brea gum were healthy, exhibiting growth curves similar to controls for both males (P?=?0.9138) and females (P?=?0.9459), thereby indicating that feed intake and utilization was not affected. A histopathological examination and weight recording of liver, kidneys, and intestine did not reveal any microscopic abnormalities or adverse toxicological effect (weights respect to control: P?>?0.1). Moreover, hematological parameters and enzyme activities were within the normal values previously reported for mice. Our findings suggest that feeding brea gum at levels up to 5% to BALB/c mice do not exert any toxicological effects, supporting its potential use as a food additive for human consumption. 相似文献
87.
88.
Helgason A Adolfsson J Dickman P Fredrikson M Steineck G 《Prostate cancer and prostatic diseases》1998,1(3):128-133
Based on traditional quality of life scales, it has been suggested that known side-effects of prostate cancer treatment do not influence the quality of life. The present authors have developed an alternative approach to quality of life assessment applying epidemiological methods. Using a self administered questionnaire, we investigated 431 prostate cancer patients and an age stratified sample of 435 randomly selected men. Patients reporting any level of distress due to waning sexual functions (66%) or urine or bowel symptoms (38%), reported a lower psychological well-being compared to patients not reporting these symptoms or patients not distressed by their symptoms. Our results stress that an intact sexual and urinary and bowel functions are important for the quality of life among elderly men with or without prostate cancer. 相似文献
89.
90.
NJ Lees AJP Rosenberg AI Hurtado-Doce J Jones N Marczin M Zeriouh A Weymann A Sabashnikov AR Simon AF Popov 《Journal of artificial organs》2016,19(4):399-402
Sepsis-induced cardiogenic shock in combination with severe acute respiratory failure represents a life-threatening combination that is often refractory to the conventional methods of treatment. We describe the case of a 33-year-old patient who developed acute cardiovascular collapse and ARDS secondary to superinfection of Panton–Valentine leukocidin—positive Staphylococcus aureus and H1N1 pneumonia who underwent successful combination therapy for severe sepsis-related cardiomyopathy and respiratory failure using extracorporeal membrane oxygenation and cytokine adsorption therapy. 相似文献