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51.
52.
Mohane Selvaraj Coumar Fang-Ying Tsai Jagat Rakesh Kanwar Sailu Sarvagalla Chun Hei Antonio Cheung 《Cancer treatment reviews》2013
Since the discovery of survivin (BIRC5) as a cancer-related molecule by Grazia Ambrosini and Dario C. Altieri at 1997, our knowledge related to the function of this molecule has been extended from simple apoptosis inhibition to complicated, interlinked processes that involve interference of mitosis, apoptosis, autophagy, and even DNA repair recently. However, despite the growing amount of knowledge related to survivin in the last ten years, the development of survivin inhibitors or survivin-related molecular therapies is surprisingly and relatively slow as compared to other therapeutic inhibitors for cancer treatment. Here, the molecular functions of survivin and the progress of development of survivin-targeting therapies are discussed in detail. Functional differences between different survivin-specific inhibitors are discussed from both structural and biochemical point of views. This review also reveals different challenges that scientists are currently facing in the development of survivin inhibitors for clinical application. Finally, future directions for the development of survivin-targeted therapies are discussed in this review. 相似文献
53.
Increasingly pre-hospital trauma management involves transfer of patients using a scoop stretcher; a number of computed tomography (CT) compatible scoops have recently appeared on the market. We sought to evaluate any differences in image quality in polytrauma patients scanned in a scoop stretcher. CT studies of 234 consecutive patients presenting between December 2011 and August 2012 at our regional level 1 tertiary trauma centre were retrospectively reviewed. Patients were allocated into two groups: those scanned with a scoop stretcher and without. CTs were reviewed by a consultant radiologist and two senior radiology trainees and graded separately for quality/artefact. A scale of 1–5 was employed: 1—uninterpretable, 2—borderline image quality, 3—acceptable, 4—good, 5—excellent. A total of 128 (54.7 %) patients were scanned in a scoop stretcher and 106 (45.3 %) were scanned without, 183 males and 51 females (average age, 46 (16–94)?years; SD, 20). The average quality grading for the patients scanned in the scoop was 4.64 compared to 4.68 in those without the scoop. There was no significant grading difference between the groups, consultant (p?=?0.096) and trainees (p?=?0.782). No artefacts were attributable to the scoop stretcher 0/128 (0 %). Following our experience, the use of scoop stretchers is recommended for efficient, safe and practical management of trauma patients and in terms of imaging, with no detrimental effect on image quality. 相似文献
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Rathor Laxmi Pant Aakanksha Nagar Abhishek Tandon Sudeep Trivedi Shalini Pandey Rakesh 《Proceedings of the National Academy of Sciences, India. Section B.》2017,87(4):1355-1362
Proceedings of the National Academy of Sciences, India Section B: Biological Sciences - The use of herbs in the form of dietary supplements and medicine is fascinating the world, owing to their... 相似文献
56.
Ankur Gupta Praveer Rai Vivek Singh Rakesh Kumar Gupta Vivek Anand Saraswat 《Indian journal of gastroenterology》2016,35(5):379-384
Background
Knowledge about anatomic variations in intrahepatic biliary ducts (IHBD) is relevant for performing biliary drainage and for avoiding bile duct injury during cholecystectomy and liver resections. Low insertion of cystic duct (LICD) is a common anatomic variant. Pancreas divisum is the commonest congenital anomaly of pancreas; it has been causally linked with recurrent acute pancreatitis (RAP).Methods
Magnetic resonance cholangiopancreaticography (MRCP) images of 500 consecutive patients were reviewed for anatomic variants of IHBD, cystic duct, and pancreatic duct.Results
Anatomy of IHBD could be evaluated in 458 MRCP’s, of these 301 (65.72 %) had ‘typical’ anatomy. The variant in 157 persons included ‘triple confluence’ in 56 (12.23 %), ‘right posterior segmental duct (RPSD) draining to left hepatic duct (LHD)’ in 64 (14 %), ‘RPSD to common hepatic duct (CHD)’ in 20 (4.4 %), ‘RPSD to cystic duct’ in 2 (0.4 %), ‘accessory duct to CHD’ in 3 (0.7 %), ‘accessory duct to right hepatic duct (RHD)’ in 1 (0.2 %), ‘segment 2 and 3 separately to CHD’ in 1 (0.2 %), and complex variants in 10 (2.2 %). Cystic duct could be evaluated in 338 patients; of these, 15 (4.4 %) had LICD. Patients with RAP had pancreas divisum more often than those without any pancreatic disease, (?/?,10 % and ?/?, 0.8 %; p?=?0.004).Conclusions
Nearly one third of MRCPs showed atypical IHBD pattern with RPSD draining to LHD being the commonest. LICD was the most common cystic duct variant. Pancreas divisum was more frequent in patients with RAP than in persons without pancreatic disease.57.
Vascular endothelial growth factor (VEGF) is a potent angiogenesis mediator. Scant reports are available defining the role of VEGF in active and inactive tubercular meningitis (TBM) with no studies on brain tuberculoma. We quantified VEGF levels by enzyme linked immunoassay (ELISA) in cerebrospinal fluid (CSF) and serum in 20 cases each with active and inactive TBM as well as 22 cases of intraparenchymal tuberculoma. VEGF expression and microvessel angiogenesis quantification was done in 7 cases where tuberculomas were excised. Significantly increased VEGF levels in CSF were found in active TBM cases (106.0+/-50.0 pg/ml) compared to inactive TBM cases (14.7+/-10.0 pg/ml) (p<0.001). Mean serum VEGF levels in active TBM, inactive TBM and tuberculoma were 694.93+/-820.66 pg/ml, 499.61+/-238.33 pg/ml and 541.0+/-389.0 pg/ml, respectively. Immunohistochemical staining of excised tuberculoma demonstrated high expression of VEGF in granulomatous areas with intense positivity in inflammatory mononuclear cells, Langhan's giant cells as well as reactive astrocytes and fibrocytes. A strong positive correlation was observed between microvessel density and VEGF expression. Serial decrease in serum VEGF levels was observed with increasing duration of therapy in tuberculoma. We conclude that increased CSF and serum VEGF levels are a measure of activity of the disease in neurotuberculosis and its gradual decrease over a period of time is probably an indicator of therapeutic response. 相似文献
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59.
Saroj Gupta Rakesh Kumar Bidani Shashi Jhamb Mahendra Kumar Agarwal 《The Journal of asthma》1996,33(5):339-348
The etiological significance of animal danders in Indian patients with nasobronchial disorders has not yet been investigated. In the present study, the role of animal danders in the etiology of bronchial asthma was studied. Extracts of danders from 6 animals along with guinea pig whole pelt were prepared. Intradermal and bronchial provocation tests with these extracts were performed on (i) 68 asthmatics and (ii) 20 nonallergic healthy volunteers. In patients, significant positive skin reactions (2+ to 4+) ranged from 1.4% each with guinea pig whole pelt and ox dander to 8.8% with dog dander extracts. None of the healthy volunteers elicited such a response. On bronchial provocation, 20% and 53.8% of the tests were positive in asthmatics showing 1 +and 2+skin reactivity, respectively. All the patients as well as controls eliciting negative intradermal responses demonstrated uniformly negative bronchial provocation tests to different dander extracts. Analysis of various clinical features of asthmatics with respect to skin positivity to dander/pelt extract was also carried out. Radioallergosorbent tests (RASTs) were performed to estimate dander-specific IgE levels in the sera of patients showing different grades of skin response to dander extracts of dog, horse, and goat. Sixty percent of sera from the patients showing 2+ to 4+ skin reactivity to various animal dander extracts showed positive RASTs. RAST positivity as well as RAST ratio increased with increase in the intensity of skin response. All the patients with positive cutaneous as well as positive bronchial responses also showed positive RASTs. Similarly, all the patients with positive skin and positive RASTs showed positive bronchoprovocation tests. These results suggested that animal danders play an important role in the etiology of bronchial asthma. Some of the clinical characteristics of asthmatics, such as (i) early age at onset of asthma, (ii) positive family history, and (iii) asthma with associated allergies, have significant bearing on the cutaneous response to various dander extracts. 相似文献
60.
This paper presents model-based information-theoretic methods to quantify the complexity of tumor microvasculature, taking into account shape, textural, and structural irregularities. The proposed techniques are completely automated, and are applicable to optical slices (3-D) or projection images (2-D). Improvements upon the prior literature include: (i) measuring local (vessel segment) as well as global (entire image) vascular complexity without requiring explicit segmentation or tracing; (ii) focusing on the vessel boundaries in the complexity estimate; and (iii) added robustness to image artifacts common to tumor microvasculature images. Vessels are modeled using a family of super-Gaussian functions that are based on the superquadric modeling primitive common in computer vision. The superquadric generalizes a simple ellipsoid by including shape parameters that allow it to approximate a cylinder with elliptical cross-sections (generalized cylinder). The super-Gaussian is obtained by composing a superquadric with an exponential function giving a form that is similar to a standard Gaussian function but with the ability to produce level sets that approximate generalized cylinders. Importantly, the super-Gaussian is continuous and differentiable so it can be fit to image data using robust non-linear regression. This fitting enables quantification of the intrinsic complexity of vessel data vis-a-vis the super-Gaussian model within a minimum message length (MML) framework. The resulting measures are expressed in units of information (bits). Synthetic and real-data examples are provided to illustrate the proposed measures. 相似文献