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31.
BACKGROUND: Fine needle aspiration (FNA) biopsy can be used to reliably classify most conditions involving lymph nodes or, at least, significantly reduce the differential diagnosis. CASE: A 70-year-old male presented with an ulcerated mass arising from the left tonsillar fossa and involving the anterior and posterior pillars. A biopsy of the tonsillar mass performed at an outside hospital was interpreted as a large cell undifferentiated carcinoma. Subsequently the patient developed systemic lymphadenopathy. A bone scan showed intense uptake within the medial tibial plateau of the left knee. FNA biopsy of the right axillary mass was interpreted at University of Cincinnati Medical College as a large cell lymphoma, multilobated type. Histologic and immunohistochemical studies of the lymph node confirmed the presence of multilobated B-cell lymphoma. Lymphoma chemotherapy was initially successful but was discontinued due to toxicity. The patient died two months after the initial cytologic diagnosis of lymphoma. CONCLUSION: Multilobated lymphomas are an unusual variant of non-Hodgkin's lymphomas (mostly B-cell type). Cytology and immunocytochemistry are useful diagnostic procedures that can help to diagnose this relatively uncommon type of lymphoma and significantly reduce the possibility of misdiagnosis.  相似文献   
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A biosurfactant producing microbe isolated from a river bank was identified as Lysinibacillus fusiformis S9. It was identified with help of biochemical tests and 16S rRNA gene phylogenetic analysis. The biosurfactant S9BS produced was purified and characterized as glycolipid. The biosurfactant showed remarkable inhibition of biofilm formation by pathogenic bacteria like Escherichia coli and Streptococcus mutans. It was interesting to note that at concentration of 40 μg ml?1 the biosurfactant did not show any bactericidal activity but restricted the biofilm formation completely. L. fusiformis is reported for the first time to produce a glycolipid type of biosurfactant capable of inhibiting biofilm formation by pathogenic bacteria. The biosurfactant inhibited bacterial attachment and biofilm formation equally well on hydrophilic as well as hydrophobic surfaces like glass and catheter tubing. This property is significant in many biomedical applications where the molecule should help in preventing biofouling of surfaces without being toxic to biotic system.  相似文献   
33.
The present study was carried out to characterize the DGAT1 gene of Riverine buffalo. Total RNA was extracted from the mammary tissue of buffalo and DGAT1cDNA were synthesized by RT-PCR, then cloned using pDRIVE cloning vector and sequenced. The sequencing revealed that the size of DGAT1 gene was 1470 bp with GC content of 62.30%. The gene encoded for 489 amino acid precursors and that it possessed 32 amino acids signal peptide. The similarity of buffalo DGAT1 mRNA sequence with that of cattle, pig, monkey, human, mice and rat were determined as 98.4, 90.7, 85.4, 85.0, 77.4 and 77.1%, respectively. Phylogenetic tree constructed from the derived DGAT1 protein sequences of 15 different species illustrated a unique branches for mammals, fly, nematode and plants. Among mammals, cattle and buffalo grouped together, whereas swine formed another group in the same branch. Four motifs were predicted in buffalo DGAT1 peptide sequence, one N-linked glycosylation site (246th position), two putative tyrosine phosphorylation site (316 and 261), one putative diacylglycerol binding site (382-392 amino acid position) and a conserved domain MBOAT (membrane bound acyl transferase from 150 to 474 amino acids) with a histidine as an active residue.  相似文献   
34.
Biofilms are the compact association of micro organisms and the communication processes in these biofilms are always a wonder. Electrical and chemical signaling mechanism are the key to understand the bacterial communication network. Quorum sensing so far has been able to explain the coordinated motion of bacteria through its chemical signaling mechanism. Bacteria residing within biofilm communities are trivial to communicate. But the recent observation in 2017 by Humphries et al. has revealed that the ion channels enabled electrical signaling mechanism can be as powerful as to attract the distant cells i.e., this signaling mechanism are capable of holding a long range behavior. As a result long range cross species communication in the bacterial world have been possible. This substantial outcome has brought this field into a new paradigm to investigate the complex co-existence of biofilm communities and distant cells with a possible scope of application in synthetic biology. In this present article, we briefly describe this new signaling mechanism and how it gives rise to a long range communication ability in bacterial communities.  相似文献   
35.
Giardia lamblia, a protozoan parasite, infects a wide variety of vertebrates, including humans. Studies indicate that this anaerobic protist possesses a limited ability to synthesize lipid molecules de novo and depends on supplies from its environment for growth and differentiation. It has been suggested that most lipids and fatty acids are taken up by endocytic and non-endocytic pathways and are used by Giardia for energy production and membrane/organelle biosynthesis. The purpose of this article is to provide an update on recent progress in the field of lipid research of this parasite and the validation of lipid metabolic pathways through recent genomic information. Based on current cellular, biochemical and genomic data, a comprehensive pathway has been proposed to facilitate our understanding of lipid and fatty acid metabolism/syntheses in this waterborne pathogen. We envision that the current review will be helpful in identifying targets from the pathways that could be used to design novel therapies to control giardiasis and related diseases.  相似文献   
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Injuries due to backward fall apart from sideways fall are a major health problem, particularly among the aged populations. The objectives of this study was to evaluate the responses to changing body configurations (angle between the trunk and impacting floor as 0°, 15°, 45° and 80°) during backward fall, based on a previously developed CT-scan-derived 3D non-linear and non-homogeneous finite element (FE) model of pelvis–femur–soft tissue complex with simplified biomechanical representation of the whole body. Under constant impact energy, these FE models evaluated the pelvic injury situations on the basis of peak impact force (7.64–16.74 kN) and peak principal compressive strain (more than 1.5%), consistent with the clinically observed injuries (sacral insufficiency, coccydynia). Also the change in location of peak strain and increase in peak impact force for changing configurations from 0° to 80° indicated the effect of whole body inertia during backward fall. It was also concluded that the inclusion of sacro-iliac and acetabular cartilages in the above FE models will further reduce above findings marginally (9.2% for 15° fall). These quantifications would also be helpful for a better design and development of safety structures such as safety floor for the nursing home or home for the aged persons.  相似文献   
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39.
Thermophilic bacteria are actively prevalent in hot water springs. Their potential to grow and sustain at higher temperatures makes them exceptional compare to other microorganism. The present study was initiated to isolate, identify and determine the feasibility of extraction of copper using thermophilic heterotrophic bacterial strain. Bacillus stearothermophilus is a thermophilic heterotrophic bacterium isolated from hot water spring, Atri, Orissa, India. This bacterium was adapted to low-grade chalcopyrite ore and its efficiency to solubilize copper from Malanjkhand low-grade ore was determined. The low-grade copper ore contains 0.27% Cu, in which the major copper-bearing mineral is chalcopyrite associated with other minerals present as minor phase. Variation in parameters such as pulp-density and temperatures were studied. After 30 days of incubation, it was found that Bacillus stearothermophilus solubilize copper up to 81.25% at pH 6.8 at 60°C.  相似文献   
40.
Compound 1 was identified as a HCV replication inhibitor from screening/early SAR triage. Potency improvement was achieved via modulation of substituent on the 5-azo linkage. Due to potential toxicological concern, the 5-azo linkage was replaced with 5-alkenyl or 5-alkynyl moiety. Analogs containing the 5-alkynyl linkage were found to be potent inhibitors of HCV replication. Further evaluation identified compounds 53 and 63 with good overall profile, in terms of replicon potency, selectivity and in vivo characteristics. Initial target engagement studies suggest that these novel carbanucleoside-like derivatives may inhibit the HCV replication complex (replicase).  相似文献   
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