In view of rising prices of crude oil due to increasing fuel demands, the need for alternative sources of bioenergy is expected to increase sharply in the coming years. Among potential alternative bioenergy resources, lignocellulosics have been identified as the prime source of biofuels and other value-added products. Lignocelluloses as agricultural, industrial and forest residuals account for the majority of the total biomass present in the world. To initiate the production of industrially important products from cellulosic biomass, bioconversion of the cellulosic components into fermentable sugars is necessary. A variety of microorganisms including bacteria and fungi may have the ability to degrade the cellulosic biomass to glucose monomers. Bacterial cellulases exist as discrete multi-enzyme complexes, called cellulosomes that consist of multiple subunits. Cellulolytic enzyme systems from the filamentous fungi, especially Trichoderma reesei, contain two exoglucanases or cellobiohydrolases (CBH1 and CBH2), at least four endoglucanases (EG1, EG2, EG3, EG5), and one beta-glucosidase. These enzymes act synergistically to catalyse the hydrolysis of cellulose. Different physical parameters such as pH, temperature, adsorption, chemical factors like nitrogen, phosphorus, presence of phenolic compounds and other inhibitors can critically influence the bioconversion of lignocellulose. The production of cellulases by microbial cells is governed by genetic and biochemical controls including induction, catabolite repression, or end product inhibition. Several efforts have been made to increase the production of cellulases through strain improvement by mutagenesis. Various physical and chemical methods have been used to develop bacterial and fungal strains producing higher amounts of cellulase, all with limited success. Cellulosic bioconversion is a complex process and requires the synergistic action of the three enzymatic components consisting of endoglucanases, exoglucanases and beta-glucosidases. The co-cultivation of microbes in fermentation can increase the quantity of the desirable components of the cellulase complex. An understanding of the molecular mechanism leading to biodegradation of lignocelluloses and the development of the bioprocessing potential of cellulolytic microorganisms might effectively be accomplished with recombinant DNA technology. For instance, cloning and sequencing of the various cellulolytic genes could economize the cellulase production process. Apart from that, metabolic engineering and genomics approaches have great potential for enhancing our understanding of the molecular mechanism of bioconversion of lignocelluloses to value added economically significant products in the future.

Platelet indices, especially PDW, are different between diabetics and controls as well as between diabetics with and without microvascular complications. Discriminant analysis using PDW and MPV could classify majority of patients with diabetic complications.

Thrombocytopenia may result from hypoproliferation in marrow, or peripheral destruction of platelets. Distinction between these two categories is usually made by bone marrow examination. Some studies in literature hint that platelet volume indices are differentially altered in various causes of thrombocytopenia. The present study was aimed at investigating the role of platelet volume indices in the differential diagnosis of thrombocytopenia. Sixty healthy controls and 60 patients (study group) with thrombocytopenia (platelet count < 150 x 10(9)/l) were included in the study. The study group was divided into two categories: hypoproliferative (megaloblastic and non-megaloblastic) and destructive thrombocytopenia. Clinical features, platelet counts and platelet indices were studied in both these categories, and statistical analysis was performed. Platelet counts in the three categories of thrombocytopenia were statistically not different. All the three platelet volume indices were significantly higher in megaloblastic group as compared to the non-megaloblastic hypoproliferative category. Platelet distribution width (PDW) was significantly different between destructive thrombocytopenia and non-megaloblastic hypoproliferative groups. In conclusion, we recommend the division of hypoproliferative category of thrombocytopenia into megaloblastic and non-megaloblastic types. Alterations in platelet indices, especially PDW can differentiate non-megaloblastic hypoproliferative category from both the destructive and megaloblastic thrombocytopenia category. These simple indices can be routinely used in the initial evaluation of a patient with thrombocytopenia.

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Background: Spindle cell carcinoma (SpCC) is a rare microscopic type of cancer of the mouth and oropharynx. Although SpCC is thought to arise from squamous cell carcinoma (SCC), it carries a worse prognosis. Aim: To find out the difference in immunohistochemical expression of cytokeratin, vimentin and smoothmuscle actin, and mutational alterations in the K-ras oncogene between the two tumours, in an attempt to characterise SpCC. Methods: Immunohistochemical analysis was performed by standard avidin-biotin complex method in 35 cases each of SpCCs and SCCs. DNA extracted from paraffin wax-embedded tumours was used for PCR followed by single-strand conformation polymorphism for mutational analysis of K-ras exon 1 and exon 2. Results: In the SpCC group, cytokeratin positivity was significantly higher in epithelial areas (52.2%) than in spindle cell areas (16.1%), whereas vimentin was more positive in spindle cell areas (18.7%) than epithelial areas (2.7%). Cells intermediate between epithelial and spindle cell areas were consistently positive for both cytokeratin and vimentin. Cytokeratin was found to be significantly more positive in SCC (72.6%) than the squamous component and spindle cell component of SpCC. In this study, no mutation was detected in the Kras gene of either the SpCC or SCC group. Conclusions: The spindle cell component of SpCC is intermixed with cells that are morphologically mesenchymal but express dual antigen-positivity characteristic of epithelial (cytokeratin) and mesenchymal (vimentin) cells. These, possibly, are cells in transition suggesting that SpCC may be a sarcomatous metaplasia of SCC.

Extrapulmonary manifestations constitute 15 to 20% of tuberculosis cases, with lymph node tuberculosis (LNTB) as the most common form of infection. However, diagnosis and treatment advances are hindered by lack of understanding of LNTB biology. To identify host response, Mycobacterium tuberculosis infected lymph nodes from LNTB patients were studied by means of transcriptomics and quantitative proteomics analyses. The selected targets obtained by comparative analyses were validated by quantitative PCR and immunohistochemistry. This approach provided expression data for 8,728 transcripts and 102 proteins, differentially regulated in the infected human lymph node. Enhanced inflammation with upregulation of T-helper1-related genes, combined with marked dysregulation of matrix metalloproteinases, indicates tissue damage due to high immunoactivity at infected niche. This expression signature was accompanied by significant upregulation of an immunoregulatory gene, leukotriene A4 hydrolase, at both transcript and protein levels. Comparative transcriptional analyses revealed LNTB-specific perturbations. In contrast to pulmonary TB-associated increase in lipid metabolism, genes involved in fatty-acid metabolism were found to be downregulated in LNTB suggesting differential lipid metabolic signature. This study investigates the tissue molecular signature of LNTB patients for the first time and presents findings that indicate the possible mechanism of disease pathology through dysregulation of inflammatory and tissue-repair processes.

Vascular tumors are rare in female genital tract (FGT). The aim of this study was to analyze the distribution of vascular tumors in FGT and to highlight their clinicopathologic features. As a retrospective study, clinical features including imaging studies, gross findings, and microscopic features of cases (ten) diagnosed as having vascular tumors of FGT over 4 years were reviewed. The age range of our cases was 12-52 years. The presenting complaint was abdominal pain/mass, postcoital bleeding, and vaginal and vulval mass. In most cases, duration of symptoms was 6 months to 2 years. Only one case had a long-standing history of 8 years. The vascular tumors occurred most commonly in ovary (six), followed by vulva (two), and one each in cervix and vagina. Clinical diagnoses ranged from cystadenoma in ovarian tumors to endocervical polyp in cervical tumor. Histologically, all were benign vascular neoplasms, ranging from hemangioma (five), lymphangioma (one), lymphangioma circumscriptum (one) to angiomatosis (two) and arteriovenous malformation (one). Thus, we conclude that vascular lesions in FGT can present with symptoms similar to epithelial malignancies and may lead to unwarranted radical surgery. Vascular lesions of cervix and vulvovaginal region pose special problem during pregnancy. Risk of Kasabach-Merritt coagulopathy has to be considered in larger vascular tumors. Most of these cases can be treated by surgery.

Introduction. According to the National Cancer Institute (NCI) guidelines in 1996, breast lesions are categorized as C1 to C5 on fine needle aspiration (FNA) cytology. Very few studies are available in the English literature analyzing histopathology outcome of C3 (atypical, probably benign) and C4 (suspicious, probably malignant) lesions. Our study aims to correlate FNA cytology of breast lump diagnosed as C3 and C4 lesion with histopathological examination. Methods. During a period of 2 years, 59 cases of C3 and 26 cases of C4 were retrieved from total 1093 cases of breast FNA. All the cases were reviewed by two cytopathologists independently. The final 24 cases of C3 and 16 cases of C4 categories were correlated with histopathological diagnosis. Result. Among C3 category, 37.5% revealed malignant findings, whereas of C4 category, 87.5% were malignant on histopathology. This difference was statistically significant (P = 0.0017). Sensitivity, specificity, positive predictive values, and negative predictive value of C4 category in diagnosing breast malignancy were 60.8%, 88.2%, 87.5%, and 62.5%, respectively. Conclusion. Although FNAC is simple, safe, cost-effective and accurate method for diagnosis of breast masses, one must be aware of its limitations particularly in C3 and C4 categories. Also, since both these categories carry different probabilities of malignancy and thus different management, we therefore, support maintaining C3 and C4 categories.