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61.
It has been revealed that the use of synthetic food preservatives has variety of various side effects and hence search of safe and effective natural preservative has become a need. With the afore said objective the present study to screen the possibility of using sesquiterpenoid extract of local folk mushroom Phellinus fastuosus as food preservative was undertaken. Microbial growth inhibition by sesquiterpenoid extract of Phellinus was evaluated in the media with natural ingredient such as milk agar (MA), tomato juice agar (TJA), wheat flour agar (WFA) and pineapple juice agar (PAJA) with the composition with Phellinus extract, sodium benzoate and combinations. Three strains of bacteria and one strain of fungus were used astest organisms. The sesquiterpenoid extract of Phellinus at 0.02% concentration significantly inhibited the growth of all test organisms on natural media and the results were comparable with sodium benzoate. Similarly combination of Phellinus extract and sodium benzoate completely inhibited the growth of all microorganisms in all media, suggesting the possibility of using the Phellinus extract as food preservative. 相似文献
62.
S G Khasabov J A Lopez-Garcia A U Asghar A E King 《British journal of pharmacology》1999,127(4):843-852
1. The in vitro hemisected spinal cord from young rat was used to investigate the mechanism of serotoninergic modulation of primary afferent-mediated synaptic transmission in the dorsal horn through activation of the 5-HT3 receptor. 2. Dorsal root-evoked excitatory post-synaptic potentials (DR-EPSPs) were recorded intracellularly from dorsal horn neurones. Extracellular recordings of the population primary afferent depolarization (PAD) and the dorsal root-evoked dorsal root reflex (DR-DRR) were made from segmental dorsal roots. 3. 5-Hydroxytryptamine (5-HT) and the selective 5-HT3 receptor agonist 1-(m-chloro-phenyl)-biguanide hydrochloride (m-ChPB) (10 and 50 microM) induced statistically significant reductions of the DR-EPSP amplitude (P<0.001) and duration (P<0.001) in the majority of dorsal horn neurones. The 5-HT3 receptor selective antagonists 3-Tropanyl-indole-3-carboxylate hydrochloride (Tropisetron, 10 microM) and N-(1-Azabicyclo[2.2.2]oct-3-yl)-6-chloro-4-methyl-3-oxo-3,4-dihydro-2H-1 ,4-benzoxazine-8-carboxamide (Y-25130, 10 microM) abolished m-ChPB-induced DR-EPSP attenuation and partially blocked the 5-HT effect. 4. m-ChPB (50 microM)-induced DR-EPSP amplitude and duration attenuation was retained in the presence of the GABA(A) receptor antagonist bicuculline (30 microM), the GABA(B) receptor antagonist saclofen (50 microM) and the opioid receptor antagonist naloxone (50 microM). 5. Both 5-HT and m-ChPB (10 and 50 microM) induced a PAD but the mean peak amplitude of 5-HT-induced PAD was significantly greater than PAD to m-ChPB (98.6+/-12 microV compared to 51.8+/-10 V for 50 microM of agonist, respectively). Tropisetron partially reduced 5-HT-induced PAD and abolished m-ChPB-induced PAD. 5-HT, but not m-ChPB, significantly (P<0.001) reduced the peak amplitude of the DR-DRR and this action of 5-HT was unaffected by Tropisetron or Y-25130. 6. These data provide experimental evidence for a putative cellular mechanism at the level of the dorsal horn for anti-nociceptive effects of 5-HT3 receptor activation. This 5-HT3-mediated modulation of sensory afferent transmission was evidently independent of inhibitory GABA- or opioid-dependent interneuronal pathways. The extent to which the 5-HT3 receptor could be involved in the operation of endogenous analgesia and sensory modulation by descending monoamine bulbo-spinal pathways is discussed. 相似文献
63.
Tasneem Asghar Shigeki Yoshida Satoshi Nakago Mayumi Morizane Norita Ohara Satoru Motoyama Stephen Kennedy David Barlow Takeshi Maruo 《Gynecological endocrinology》2005,20(2):59-63
Endometriosis is a complex trait, which means that multiple susceptibility genes interact with one another and the environment to produce the phenotype. One of the genes previously implicated in the disease is CYP17; this encodes the enzyme P450c17alpha, which plays a vital role in steroid biosynthesis in the ovary. The presence of a single nucleotide polymorphism (T-->C) in the 5'-promoter region of the gene creates a new recognition site for the restriction enzyme MspA1 producing a mutant allele (A2), which affects circulating estrogen levels. In this study, we compared the frequency of the CYP17 MspA1 polymorphism in two different ethnic populations. DNA was obtained from (1) 94 women with revised American Fertility Society (rAFS) stage III-IV endometriosis and 97 male blood donors in the UK, and (2) 130 women with rAFS stage III-IV endometriosis and 179 female newborn infants in Japan. No significant differences in allele or genotype frequencies were seen in either population. The genotype distribution in the UK population was 33/94 [35.1%] (cases) and 39/97 [40.2%] (controls) for A1A1 (homozygous wild-type); 43/94 [45.7%] (cases) and 44/97 [45.4%] (controls) for A1A2; and 18/94 [19.1%] (cases) and 14/97 [14.4%] (controls) for A2A2. The genotype distribution in the Japanese population was 31/130 [23.9%] (cases) and 57/179 [31.8%] (controls) for A1A1; 73/130 [56.2%] (cases) and 89/179 [49.7%] (controls) for A1A2; and 26/130 [20.0%] (cases) and 33/179 [18.4%] (controls) for A2A2. The CYP17 MspA1 polymorphism is probably not associated with endometriosis in either the UK or the Japanese population. 相似文献
64.
The effects of the anticonvulsants remacemide [(±)‐2‐amino‐N‐(1‐methyl‐1,2‐diphenylethyl)‐acetamide hydrochloride] and its des ‐glycinated metabolite AR‐R12495AA [(±)‐1‐methyl‐1,2‐diphenylethylamine‐ monohydrochloride] on primary afferent‐induced synaptic transmission and frequency‐dependent summation of synaptic potentials were assessed in the young rat spinal cord in vitro. Behavioural studies in the rat determined the effects of these anticonvulsant compounds in the carrageenan model of inflammation. Recordings of the extracellular dorsal root‐evoked ventral root potential (DR‐VRP) revealed a significant reduction of the duration and t1/2 decay of the long latency, slow DR‐VRP by remacemide (50 and 100 μM) and AR‐R12495AA (25, 50 and 100 mM). The short‐latency, fast monosynaptic DR‐VRP peak was reduced by only the highest concentration of AR‐R12495AA (100 μM). In intracellular dorsal root‐evoked excitatory postsynaptic potentials (DR‐EPSPs) of single ventral horn neurons, AR‐R12495AA (100 μM) attenuated the time course of the long‐latency (slow) EPSP. Frequency‐dependent (0.5–2.0 Hz) summation of dorsal root‐evoked synaptic events (recorded extracellularly as the cumulative ventral root depolarization (CVRD), and intracellularly as wind‐up) was attenuated by remacemide (100 μM) and AR‐R12495AA (50 and 100 μM). Pre‐treatment with intra‐peritoneal injection of 75 mg/kg of remacemide or AR‐R12495AA caused a significant reduction of carrageenan‐induced mechanical hyperalgesia and oedema. These electrophysiological and behavioural data provide evidence that remacemide and AR‐R12495AA may also possess analgesic and anti‐inflammatory activity. Copyright 2000 European Federation of Chapters of the International Association for the Study of Pain 相似文献
65.
Manuel K. Rausch Marcin Malinowski Penny Wilton Asghar Khaghani Tomasz A. Timek 《Annals of biomedical engineering》2018,46(3):443-451
Functional tricuspid regurgitation is a significant source of morbidity and mortality in the US. Furthermore, treatment of functional tricuspid regurgitation is suboptimal with significant recurrence rates, which may, at least in part, be due to our limited knowledge of the relationship between valvular shape and function. Here we study the dynamics of the healthy in vivo ovine tricuspid annulus to improve our understanding of normal annular deformations throughout the cardiac cycle. To this end, we determine both clinical as well as engineering metrics of in vivo annular dynamics based on sonomicrometry crystals surgically attached to the annulus. We confirm that the tricuspid annulus undergoes large dynamic changes in area, perimeter, height, and eccentricity throughout the cardiac cycle. This deformation may be described as asymmetric in-plane motion of the annulus with minor out-of-plane motion. In addition, we employ strain and curvature to provide mechanistic insight into the origin of this deformation. Specifically, we find that strain and curvature vary considerable across the annulus with highly localized minima and maxima resulting in aforementioned configurational changes throughout the cardiac cycle. It is our hope that these data provide valuable information for clinicians and engineers alike and ultimately help us improve treatment of functional tricuspid regurgitation. 相似文献
66.
67.
Background
Succinate dehydrogenase (SDH)- deficient renal cell carcinoma (RCC) is a newly identified rare subtype of RCC, having only gained acceptance from the World Health Organization in 2016. To the best of our knowledge, there are only 55 reported cases worldwide. Here, we report a new case of SDH-deficient RCC.Case presentation
A 49-year-old male patient was incidentally found to have a large right renal mass. He had no personal or family history of paragangliomas (PGL), pheochromocytomas (PC), or gastrointestinal stromal tumors (GIST). The neoplasm was unilateral and unifocal. He underwent an open partial nephrectomy. Detailed pathological analysis was conducted to confirm the diagnosis. Genetic testing revealed a pathogenic mutation in the SDHB gene. He has been followed for 24?months now and has remained well without any evidence of local or distant recurrence. In this report we describe our experience with this diagnosis and review the relevant clinical, pathological, and genetic features.Conclusions
Without the identification of SDHB deficiency, this patient’s personal and familial predisposition to PC, PGL, GIST and metachronous RCCs may have gone undetected despite his RCC diagnosis. When faced with an eosinophilic RCC, pathologists should routinely search for vacuoles or flocculent cytoplasmic inclusions. When these are present, or in cases of difficult eosinophilic renal tumors, staining for SDHB is recommended. For tumours without adverse pathologic features (i.e. high nuclear grade, coagulative necrosis, or sarcomatoid differentiation) excision alone may be a reasonable option, with the addition of regular surveillance for PC and PGLs in those found to harbor germline SDH mutations.68.
69.
Purpose The dosimetric features of an unflattened 6-MV photon beam of an Elekta SL-25 linac was calculated by the Monte Carlo (MC)
method.
Material and methods The head of the Elekta SL-25 linac was simulated using the MCNP4C MC code. The accuracy of the model was evaluated using measured
dosimetric features, including depth dose values and dose profiles in a water phantom. The flattening filter was then removed,
and beam dosimetric properties were calculated by the MC method and compared with those of the flattened photon beam.
Results Our results showed a significant (twofold) increase in the dose rate for all field sizes. Also, the photon beam spectra for
an unflattened beam were softer, which led to a steeper reduction in depth doses. The decrease in the out-of-field dose and
increase in the contamination electrons and a buildup region dose were the other consequences of removing the flattening filter.
Conclusion Our study revealed that, for recent radiotherapy techniques, the use of multileaf collimators for beam shaping removing the
flattening filter could offer some advantages, including an increased dose rate and decreased out-of-field dose. 相似文献
70.