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1.
M Devi S Nalin Kumar K Ranganathan T R Saraswathi 《Indian journal of dental research》2004,15(4):149-151
Intravascular papillary endothelial hyperplasia (IPEH) is an unusual vascular lesion of proliferating endothelial cells. It is more frequently seen in the extremities, particularly in the fingers. Oral IPEH has been reported with the common sites being lip, tongue, and buccal mucosa. In this article, we present a case of oral IPEH of the floor of the mouth, an unusual location, presenting in a 9-month-old male. The histogenesis, histologic features, and ultrastructural features are also reviewed. A misdiagnosis of angiosarcoma can be made in a case of IPEH due to similar histopathologic features. It is imperative to rule out this error by an elaborate histopathologic evaluation ofthese lesions. 相似文献
2.
T Rooban T R Saraswathi Antony George Elizabeth Joshua K Ranganathan 《Indian journal of dental research》2004,15(4):129-132
BACKGROUND: Habitual arecanut chewing is associated with Oral Submucous Fibrosis (OSF). High copper content in arecanut plays a vital role in pathogenesis of OSF. This study evaluates the copper-staining pattern of buccal epithelial cells in oral cytological smears of non-chewers, chewers, and OSF. MATERIALS & METHODS: Alcohol fixed buccal epithelial smears of 10 histopathologically confirmed cases of OSF, 10 chewers without lesion, and 5 nonchewers were stained with modified Rhodamine technique and studied under the light microscope. Buccal epithelial smears of non-chewers dipped in copper sulphate solution were used as known positive for copper. RESULT: Copper appeared as shades of palered within the cytoplasm of chewers and did not show any stain in non-chewers. Intense red stain was seen in OSF smears as dark granules within the cytoplasm. CONCLUSION: Intense staining of copper in OSF buccal smears, than in the chewers supports the role of copper in the pathogenesis of OSF. 相似文献
3.
Site-specific cleavage and joining of single-stranded DNA by VirD2 protein of Agrobacterium tumefaciens Ti plasmids: analogy to bacterial conjugation. 总被引:18,自引:2,他引:16 下载免费PDF全文
W Pansegrau F Schoumacher B Hohn E Lanka 《Proceedings of the National Academy of Sciences of the United States of America》1993,90(24):11538-11542
As an early stage of plant transformation by Agrobacterium tumefaciens, the Ti plasmid is nicked at the border sequences that delimit the T-DNA. Cleavage results in covalent attachment of VirD2 to the 5' terminal of the nicked strand by a process resembling initiation of DNA transfer that occurs in the donor cell during bacterial conjugation. We demonstrate that this cleavage can be reproduced in vitro: VirD2 protein, the border-cleaving enzyme, was overproduced and purified. Cleavage assays were performed with single-stranded oligodeoxyribonucleotides encompassing the Ti plasmid border region or the transfer origin's nick region of the conjugative plasmid RP4. VirD2 of pTiC58 cleaves both border- and nick region-containing oligonucleotides. However, the relaxase TraI of RP4 can cut only the cognate nick regions. The respective proteins remain covalently bound to the 5' end of the cleavage sites, leaving the 3' termini unmodified. VirD2-mediated oligonucleotide cleavage was demonstrated to be an equilibrium reaction that allows specific joining of cleavage products restoring border and nick regions, respectively. The possible role of VirD2 in T-DNA integration into the plant cell's genome is discussed in terms of less stringent target-sequence requirements. 相似文献
4.
5.
Between January 1988 and December 1989 Aeromonas species were isolated from 45 (1.8%) of 2,480 patients with acute gastroenteritis. No other bacterial enteric pathogens were found in any of these 45 patients. Of the 45 Aeromonas isolates, 35 strains (77.8%) were Aeromonas hydrophila, 7 (15.5%) were Aeromonas sobria, and 3 (6.7%) were Aeromonas caviae. Most of the patients were under 5 years of age. No bacterial enteric pathogens, including Aeromonas species, were isolated from 512 age- and sex-matched control subjects. Examination of the Aeromonas isolates for exotoxin production (enterotoxin and hemolysin) indicated that all strains, irrespective of species, were enterotoxin positive (rabbit ileal loop model) and hemolysin positive (rabbit erythrocyte model). These results suggest that Aeromonas species are potential enteric pathogens in our geographical region. 相似文献
6.
Almanza Jennifer I. Karbeah J.Mag Tessier Katelyn M. Neerland Carrie Stoll Kathrin Hardeman Rachel R. Vedam Saraswathi 《Maternal and child health journal》2022,26(4):895-904
Maternal and Child Health Journal - National studies report that birth center care is associated with reduced racial and ethnic disparities and reduced experiences of mistreatment. In the US, there... 相似文献
7.
Sequence-related protein export NTPases encoded by the conjugative transfer region of RP4 and by the cag pathogenicity island of Helicobacter pylori share similar hexameric ring structures 下载免费PDF全文
Krause S Barcena M Pansegrau W Lurz R Carazo JM Lanka E 《Proceedings of the National Academy of Sciences of the United States of America》2000,97(7):3067-3072
RP4 TrbB, an essential component of the conjugative transfer apparatus of the broad-host-range plasmid RP4, is a member of the PulE protein superfamily involved in multicomponent machineries transporting macromolecules across the bacterial envelope. PulE-like proteins share several well conserved motifs, most notable a nucleoside triphosphate binding motif (P-loop). Helicobacter pylori HP0525 also belongs to the PulE superfamily and is encoded by the pathogenicity island cag, involved in the inflammatory response of infected gastric epithelial cells in mammals. The native molecular masses of TrbB and HP0525 as determined by gel filtration and glycerol gradient centrifugation suggested a homohexameric structure in the presence of ATP and Mg(2+). In the absence of nucleotides and bivalent cations, TrbB behaved as a tetramer whereas the hexameric state of HP0525 remained unaffected. Electron microscopy and image processing demonstrated that TrbB and HP0525 form ring-shaped complexes (diameter: 12 nm) with a central region (diameter: 3 nm) of low electron density when incubated in the presence of ATP and Mg(2+). However, the TrbB average image appeared to be more elliptical with strong twofold rotational symmetry whereas HP0525 complexes are regular hexagons. Six well defined triangle-shaped areas of high electron density were distinguishable in both cases. Covalent crosslinking of TrbB suggests that the hexameric ring is composed from a trimer of dimers, because only dimeric, tetrameric, and hexameric species were detectable. The toroidal structure of TrbB and HP0525 suggests that both proteins catalyze a repetitive process, most probably translocating a cognate substrate across the inner membrane. 相似文献
8.
Vijaya Kumar Muppiri Syed Nasheed Ali Kumar Ravinuthala Venkat Krishna Lanka Satya Rama 《Indian Journal of Thoracic and Cardiovascular Surgery》2011,27(4):161-164
Introduction
Combined aortic and mitral valve disease is usually of rheumatic origin. In these patients we often encounter problem of small valve annuli particularly with aortic annulus. It is still debated whether a small prosthesis should be used or aortic root should be enlarged to prevent Patient Prosthesis Mismatch (PPM). This study was undertaken to review our strategy and feasibility of Aortic Root Enlargement (ARE) in patient undergo Double Valve Replacement (DVR) to avoid mismatch without increase in cost of treatment, morbidity or mortality. 相似文献9.
Sequence identity in the nick regions of IncP plasmid transfer origins and T-DNA borders of Agrobacterium Ti plasmids. 总被引:22,自引:4,他引:22 下载免费PDF全文
V L Waters K H Hirata W Pansegrau E Lanka D G Guiney 《Proceedings of the National Academy of Sciences of the United States of America》1991,88(4):1456-1460
The IncP antibiotic-resistance plasmids transfer to a broad range of bacterial species. The RK2 origin of DNA transfer (oriT) consists of a 250-base-pair segment including the single-stranded cleavage site (nic) needed to generate the DNA strand believed to be transferred. Deletion derivatives and a bank of hydroxylamine-generated oriT mutants were screened for loss of transferability. DNA regions flanking both sides of nic are required for optimal transfer of the oriT clone. Of the chemically induced mutants, critical base-pair changes that dramatically reduced transfer frequency were found in a 10-base-pair region adjacent to nic. Relaxation (nicking) assays performed with these point mutants using protein-DNA complexes reconstituted in vitro revealed a correlation between DNA nicking and transfer frequency. Base-pair changes within the proximal arm of an inverted repeat upstream from the nick site resulted in reduced binding of the essential transfer protein TraJ and correspondingly reduced transfer frequencies. The results support a model of relaxosome formation involving at least two essential proteins: TraI and TraJ. The nick region defined by the point mutants was located in a segment known to be nearly identical in the related plasmid R751. This sequence was also found to be highly conserved in both border junctions of the transfer DNA (T-DNA) of plant tumor-inducing plasmids of Agrobacterium tumefaciens, indicating a relationship between IncP-mediated broad-host-range bacterial conjugation and T-DNA transfer to plants. 相似文献
10.
Arora A Acharya SR Muliya VS Sharma P 《Quintessence international (Berlin, Germany : 1985)》2012,43(3):187-190
Multiple idiopathic cervical resorption is an uncommon condition, the etiology of which remains unknown. The case of a 36-year-old woman with idiopathic resorption in the cervical areas of multiple teeth is presented. Her medical history was noncontributory, but her dental history was valuable in reaching a diagnosis. Hematologic and endocrinal investigations were unremarkable, but a computed tomography scan revealed relevant information. The progression of the lesion and involvement of multiple teeth without any pattern or chronology are challenges faced when diagnosing and treating this condition. 相似文献