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1.

Background

Multiple myeloma (MM) is a hematologic malignancy of plasma cell origin. MM primarily affects bone marrow, but extramedullary sites can also be involved. Myelomatous pleural effusion (MPE) is an atypical and rare complication of MM. We aimed to systematically study the incidence and clinicopathologic profile of patients with MPE in a real-world setting.

Patients and Methods

In this retrospective study, 415 consecutive patients with MM managed at a tertiary care center in North India during a study period of January 1, 2010 to December 31, 2015 were evaluated for MPE. The patients with MPE were analyzed for their clinical profile, diagnosis, treatment, and outcomes.

Results

Of these 415 patients, 11 (2.65%) patients had MPE. The median age of the study population was 50 years with male preponderance. The majority of these patients had immunoglobin (Ig)G Kappa disease. All patients had higher than International Staging System stage I disease. MPE was a presenting feature at MM diagnosis in 45.45% (n = 5) of the patients, whereas the rest developed MPE during follow-up. MPE presented predominantly (81.8%) as a unilateral effusion. Concurrent extramedullary involvement at other site was seen in 45.45% (n = 5), with 3 (27%) patients having concurrent myelomatous ascites. Six of these were managed aggressively, whereas 5 patients opted for palliation. The outcomes were dismal (90.9% mortality), with a median survival of 2.47 months.

Conclusion

MPE is a rare entity, and positive outcomes of therapy remain low with dismal prognosis.  相似文献   
2.
Electrocardiogram (ECG) signal gives a lot of information on the physiology of heart. In reality, noise from various sources interfere with the ECG signal. To get the correct information on physiology of the heart, noise cancellation of the ECG signal is required. In this paper, the effectiveness of extended Kalman smoother (EKS) with the differential evolution (DE) technique for noise cancellation of the ECG signal is investigated. DE is used as an automatic parameter selection method for the selection of ten optimized components of the ECG signal, and those are used to create the ECG signal according to the real ECG signal. These parameters are used by the EKS for the development of the state equation and also for initialization of the parameters of EKS. EKS framework is used for denoising the ECG signal from the single channel. The effectiveness of proposed noise cancellation technique has been evaluated by adding white, colored Gaussian noise and real muscle artifact noise at different SNR to some visually clean ECG signals from the MIT-BIH arrhythmia database. The proposed noise cancellation technique of ECG signal shows better signal to noise ratio (SNR) improvement, lesser mean square error (MSE) and percent of distortion (PRD) compared to other well-known methods.  相似文献   
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The role that free radicals in general and oxygen radicals in particular play in carcinogenesis has attracted considerable attention in recent years. The oxygen radicals are undesirable but inevitable products of aerobic metabolism in the normal living cell. The cellular antioxidant defense system maintains an appropriate balance between necessary oxidative events and those that are excessive. When this critical balance cannot be maintained because of the overloading of the cellular redox system, oxygen radicals can induce cell damage. They can influence carcinogenesis by inducing DNA damage from direct oxidation or indirectly from DNA-binding products of lipid peroxidation. Oxygen radicals can induce conformational changes in the plasma membrane by lipid peroxidation and protein degradation, thus influencing membrane-associated cellular activities. They are capable of affecting membrane-bound protein kinases, growth factors and their receptors, and, therefore, signal transduction and oncogene activation. Thus, the oxygen radicals can have a major influence on oncogenes and oncogenesis.  相似文献   
6.
Recent evidence suggests that a variety of hypothalamic neuropeptides may mediate interneuronal communication to coordinate diverse neuroendocrine and behavioral functions. In this work, we describe the effects of neuropeptide Y (NPY) on feeding and sexual behaviors. We observed that central administration of bolus NPY stimulated a robust, dose-related feeding response in satiated male and female rats. Continuous NPY receptor activation also evoked dose-related, intermittent feeding in a manner normally observed during nocturnal feeding. It appears that the paraventricular nucleus in the hypothalamus may be the primary site of NPY action because the anticipated reciprocal changes in NPY concentrations, in response to food deprivation followed by ad libitum food intake, occurred only in this site. Additional findings revealed that NPY-induced feeding may follow either substantial reduction or complete restraint of an inhibitory influence on feeding mediated by alpha 2-adrenoreceptor systems in satiated rats. Further, NPY was found to suppress male and female sexual behaviors. The suppressive effects on sexual behavior were apparent prior to or at the time of the onset of feeding after NPY administration. These observations may provide a neurochemical basis for clinical and animal studies on disorders of feeding associated with diminished reproductive functions.  相似文献   
7.
Oxygen free radicals (OFR) are implicated in thepathogenesis of stress, chemically induced gastriclesions, and gastrointestinal injury. Theconcentration-dependent scavenging abilities of bismuthsubsalicylate (SBS), colloidal bismuth subcitrate (CBS), andselected OFR scavengers, including superoxide dismutase(SOD), catalase, mannitol, and allopurinol were examinedagainst biochemically or chemically generated superoxide anion, hydroxyl radical, andhypochlorite radical plus hypochlorous acid based on achemiluminescence assay. Furthermore, both gastric (GM)and intestinal mucosa (IM) were individually exposed in vitro to these free radical generatingsystems, and the concentration-dependent protectiveabilities of SBS and CBS against lipid peroxidation (LP)were compared with selected OFR scavengers. In addition, 24-hr fasted rats were orally treated with thenecrotizing agents 0.6 M HCl, 0.2 M NaOH, 80% ethanol,and aspirin (200 mg/kg). The extent of tissue injury inthe GM and IM was determined by assessing LP, DNA fragmentation, and membrane microviscosity.Dose- and time-dependent in vivo protective abilities ofCBS (100 mg/kg) and SBS (15 mg/kg) were also assessed.Following incubations with superoxide anion and hydroxyl radical generating systems in thepresence of 125 mg SBS/liter, approximately 47% and 61%inhibitions were observed in the chemiluminescenceresponse, respectively, while 48% and 46% inhibitions were observed with 125 mg CBS/liter. SBS andCBS exerted similar abilities towards hypochloriteradical plus hypochlorous acid. Approx. 3.1- and3.7-fold increases in LP were observed in the GM and IMof rats following oral administration of 0.6 MHCl. Pretreatment of the rats with SBS and CBS decreased0.6 M HCl-induced LP in the GM by approx. 39% and 27%,respectively, with similar decreases in LP in the IM. SBS exhibited better protectiveabilities towards 0.6 M HCl and 0.2 m NaOH-induced GMand IM injury as compared to CBS. SBS and CBS providedsimilar protection towards 80% ethanol-induced gastric injury, while CBS exerted a superior protectiveability towards aspirin-induced gastric injury. Theresults demonstrate that both SBS and CBS can scavengereactive oxygen species and prevent tissue damage produced by OFR.  相似文献   
8.
Vegetarians may have subtle nutritional deficiencies which have been related to the occurrence of an unrecognized malabsorption syndrome. The excess phytate content in cereals, nuts, legumes and oilseeds which represent the mainstay of their food intake, seems to play a central role in the pathogenesis of this malabsorption syndrome as an inverse relationship has been shown to link the phytate content of the diet with the intestinal absorption of trace minerals and proteins. We postulate that manipulating the endogenous digestive microflora of subjects on a vegetarian diet through administering probiotic lactic bacteria would represent an innovative tool to counteract the occurrence of the malabsorption syndrome dependent on the high phytate content of their diet. Even though there are no data about the composition of endogenous digestive microflora in subjects on a vegetarian diet, we expect that probiotic lactobacilli can interact with or affect distinct yet interrelated components within the intestinal milieu, such as epithelial cells, enteric flora, and/or mucosal immune cells. This would ultimately translate into the correction of the unregulated mechanisms implicated in the altered intestinal absorption of trace metals and proteins commonly seen in vegetarians. Clinical experience with probiotic therapy of patients with inflammatory bowel disease fully agrees with this view. One additional point of interest is that probiotic lactobacilli, and other species of the endogenous digestive microflora as well, are an important source of the enzyme phytase which catalyses the release of phosphate from phytate and hydrolyses the complexes formed by phytate and metal ions or other cations, rendering them more soluble ultimately improving and facilitating their intestinal absorption. The regular intake of probiotic preparation, may represent a cheap and safe tool in order to convert a diet with a low potential for bioavailability of trace minerals and proteins, such as the vegetarian diet, into a diet with a high bioavailability potential. The benefit of such an approach would not be restricted to vegetarians.  相似文献   
9.
Codon usage studies have been carried out on the coding sequences of Thermoplasma acidophilum, which is an archaeon and grows at very low pH and high temperature. Overall codon usage data analysis indicates that all the four bases are almost equifrequent at the third position of codons, which is expected (since genomic GC % of this genome is about 46%). However, multivariate statistical analysis indicates that there are two major trends in the codon usage variation among the genes in this organism. In the first major trend it is observed that genes having G and C ending codons are clustered at one end while, A and T ending ones are clustered at the other end. We have also found a significant positive correlation between the expressivities of genes and GC contents at the synonymous third codon positions. In the second major trend, it is seen that the genes are clustered into three distinct parts. A comparative analyses of codon usage data of T. acidophilum and Sulfolobus solfataricus reveals that one of the three clusters of genes of T. acidophilum is very similar to a considerable number of S. solfataricus genes, suggesting possible occurrences of lateral gene transfer between these two microorganisms as reported by earlier workers.  相似文献   
10.
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