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161.
Oral mucoceles are the most common benign minor salivary gland lesions. It is of interest to document the prevalence of oral mucocele among outpatients at the Saveetha Dental Hospital, India. We used patient data (12 case records) with mucocele occurrence for this analysis. Data included age, gender, diagnosis, lesion duration and relevant dental history. Data shows that oral mucocele were seen predominantly in males (66%) when compared to females (34%). The most affected site in the oral cavity was the lower lip (58%). Thus, data shows that oral mucocele was predominantly seen in males compared to females. Data also shows that the lower lip is often affected. 相似文献
162.
White JA Pliquett U Blackmore PF Joshi RP Schoenbach KH Kolb JF 《European biophysics journal : EBJ》2011,40(8):947-957
The initial effect of nanosecond pulsed electric fields (nsPEFs) on cells is a change of charge distributions along membranes.
This first response is observed as a sudden shift in the plasma transmembrane potential that is faster than can be attributed
to any physiological event. These immediate, yet transient, effects are only measurable if the diagnostic is faster than the
exposure, i.e., on a nanosecond time scale. In this study, we monitored changes in the plasma transmembrane potential of Jurkat
cells exposed to nsPEFs of 60 ns and amplitudes from 5 to 90 kV/cm with a temporal resolution of 5 ns by means of the fast
voltage-sensitive dye Annine-6. The measurements suggest the contribution of both dipole effects and asymmetric conduction
currents across opposite sides of the cell to the charging. With the application of higher field strengths the membrane charges
until a threshold voltage value of 1.4–1.6 V is attained at the anodic pole. This indicates when the ion exchange rates exceed
charging currents, thus providing strong evidence for pore formation. Prior to reaching this threshold, the time for the charging
of the membrane by conductive currents is qualitatively in agreement with accepted models of membrane charging, which predict
longer charging times for lower field strengths. The comparison of the data with previous studies suggests that the sub-physiological
induced ionic imbalances may trigger other intracellular signaling events leading to dramatic outcomes, such as apoptosis. 相似文献
163.
Mani I Kumar R Singh M Nagpure NS Kushwaha B Srivastava PK Rao DS Lakra WS 《Molecular biology reports》2011,38(4):2637-2647
Molecular cytogenetic studies were carried out for localization of 18S and 5S ribosomal DNAs on chromosomes of three cyprinid
fish species viz., T.
khudree, T. mussullah and T. mosal mahanadicus using two color fluorescence in situ hybridization (FISH). All the species typically possessed 100 diploid chromosomes with
minor variation in karyo-morphology. The 18S rDNA signals were observed on two pair of chromosomes in T. khudree and T. mussullah, and three pairs in T. mosal mahanadicus. The location of 18S signals also showed affinity to silver nitrate and chromomycin A3 staining. Similarly, variation in localization of 5S rDNA among the three species has been detected with the presence of
FISH signals on one pair of chromosome in T. khudree and T. mussullah, and on two pairs in T. mosal mahanadicus. These molecular markers could be used as species specific markers for taxonomic identification and can further add in understanding
the dynamics of genome organization and karyotypic evolution of these species. The 18S rDNA region was sequenced that generated
1811, 1810 and 1776 bp long 18S sequence in T. khudree, T. mussullah and T. mosal mahanadicus, respectively. The 18S rDNA sequence showed 95–98% identity among the subject species. Similarly, 5S sequencing generated
203 bp long fragments in these species with 100% identity in coding and 9.63% variability in non-transcribed spacer regions.
The nucleotide sequence variations could be used for understanding the genetic diversity and will add new informative characters
in comparative genomics. These results, in general, would enhance the value and interpretation of ecological assessment data
for conservation of Tor species. 相似文献
164.
Paszczynski AJ Paidisetti R Johnson AK Crawford RL Colwell FS Green T Delwiche M Lee H Newby D Brodie EL Conrad M 《Biodegradation》2011,22(6):1045-1059
The Test Area North (TAN) site at the Idaho National Laboratory near Idaho Falls, ID, USA, sits over a trichloroethylene (TCE) contaminant plume in the Snake River Plain fractured basalt aquifer. Past observations have provided evidence that TCE at TAN is being transformed by biological natural attenuation that may be primarily due to co-metabolism in aerobic portions of the plume by methanotrophs. TCE co-metabolism by methanotrophs is the result of the broad substrate specificity of microbial methane monooxygenase which permits non-specific oxidation of TCE in addition to the primary substrate, methane. Arrays of experimental approaches have been utilized to understand the biogeochemical processes driving intrinsic TCE co-metabolism at TAN. In this study, aerobic methanotrophs were enumerated by qPCR using primers targeting conserved regions of the genes pmoA and mmoX encoding subunits of the particulate MMO (pMMO) and soluble MMO (sMMO) enzymes, respectively, as well as the gene mxa encoding the downstream enzyme methanol dehydrogenase. Identification of proteins in planktonic and biofilm samples from TAN was determined using reverse phase ultra-performance liquid chromatography (UPLC) coupled with a quadrupole-time-of-flight (QToF) mass spectrometer to separate and sequence peptides from trypsin digests of the protein extracts. Detection of MMO in unenriched water samples from TAN provides direct evidence of intrinsic methane oxidation and TCE co-metabolic potential of the indigenous microbial population. Mass spectrometry is also well suited for distinguishing which form of MMO is expressed in situ either soluble or particulate. Using this method, pMMO proteins were found to be abundant in samples collected from wells within and adjacent to the TCE plume at TAN. 相似文献
165.
Gadthula S Rawal RK Sharon A Wu D Korba B Chu CK 《Bioorganic & medicinal chemistry letters》2011,21(13):3982-3985
An efficient method was developed for the synthesis of 6-exocyclic methylene carbocyclic intermediate 4. The Simmons-Smith cyclopropanation protocol was applied on the 6-exocyclic methylene of intermediate 4 and demonstrated its utility for the synthesis of novel class of a spiro-carbocyclic nucleoside analog 8. The titled compound 8 demonstrated a significant antiviral activity against HCV with EC50 values of 0.273 and 0.368 μM in genotypes 1A and 1B, respectively. 相似文献
166.
The objective was to determine the in vitro developmental competence of buffalo oocytes collected from abattoir-derived ovaries at various stages of the estrous cycle and follicular status. In Experiment 1, ovaries (n=476 pairs) were collected and divided into the following five groups: (a) ovaries with a corpus hemorragicum and no dominant follicle (CH-NO-DF); (b) ovaries with a mature functional corpus luteum (CL) and a dominant follicle (CL-DF); (c) ovaries with a mature functional CL and no dominant follicle (CL-NO-DF); (d) ovaries with a regressing CL and a dominant follicle (RCL-DF); and (e) ovaries without any luteal structures and only small follicles (ANEST). In Experiment 2, 144 pairs of ovaries with a CL (or regressing CL) and a dominant follicle were collected and follicles were classified as dominant, largest subordinate, and subordinate. In both experiments, the dominant follicle was defined as any follicle >10mm in diameter that exceeded the diameter of all other (subordinate) follicles. Although oocytes were collected from each group of ovaries, only Grades A or B oocytes were used for in vitro embryo production. Cleavage rates were higher (P<0.05) from oocytes collected from ovaries in the CH-NO-DF (59.6%) and CL-NO-DF (59.2%) groups than those collected from CL-DF (52.2%) and ANEST (43.6%) groups. The yield of transferable embryos was higher (P<0.05) from oocytes collected from CH-NO-DF (27.4%) and CL-NO-DF (24.0%) ovaries than from CL-DF (16.2%), RCL-DF (15.4%), and lowest (P<0.05) from ANEST (8.8%). In Experiment 2, oocytes from the dominant follicle had a higher (P<0.05) cleavage rate (65.2 %) and transferable embryo yield (30.2%) than those collected from the largest subordinate and subordinate follicles. In conclusion, oocyte competence depended on the morphofunctional state of ovaries. Oocyte development was maximal in pairs of ovaries with a corpus hemorragicum or CL and no dominant follicle; in paired ovaries with a CL and a dominant follicle, development was maximal in oocytes derived from the dominant follicle. 相似文献
167.
Modulating role of RNA structure in alternative splicing of a critical exon in the spinal muscular atrophy genes 总被引:8,自引:2,他引:6
Humans have two nearly identical copies of the survival motor neuron (SMN) gene, SMN1 and SMN2. Homozygous loss of SMN1 causes spinal muscular atrophy (SMA). SMN2 is unable to prevent the disease due to skipping of exon 7. Using a systematic approach of in vivo selection, we have previously demonstrated that a weak 5′ splice site (ss) serves as the major cause of skipping of SMN2 exon 7. Here we show the inhibitory impact of RNA structure on the weak 5′ ss of exon 7. We call this structure terminal stem–loop 2 (TSL2). Confirming the inhibitory nature of TSL2, point mutations that destabilize TSL2 promote exon 7 inclusion in SMN2, whereas strengthening of TSL2 promotes exon 7 skipping even in SMN1. We also demonstrate that TSL2 negatively affects the recruitment of U1snRNP at the 5′ ss of exon 7. Using enzymatic structure probing, we confirm that the sequence at the junction of exon 7/intron 7 folds into TSL2 and show that mutations in TSL2 cause predicted structural changes in this region. Our findings reveal for the first time the critical role of RNA structure in regulation of alternative splicing of human SMN. 相似文献
168.
Rawal RK Tripathi R Katti SB Pannecouque C De Clercq E 《Bioorganic & medicinal chemistry》2007,15(4):1725-1731
Compounds having isothiourea or thiourea functional group have shown high anti-HIV-1 activity. Therefore, a series of 2-aryl-3-heteroaryl-1,3-thiazolidin-4-ones were designed, synthesized, and evaluated for anti-HIV-1 RT activity. The results of in vitro tests showed that the compound 9 exhibited EC50 at 0.26 microM with minimal toxicity in MT-4 cells as compared to 0.35 microM for thiazobenzimidazole (TBZ). It may be inferred from the present data that majority of compounds in this series exhibit higher selectivity index than TBZ. 相似文献
169.
Chen N Garner AL Chen G Jing Y Deng Y Swanson RJ Kolb JF Beebe SJ Joshi RP Schoenbach KH 《Biochemical and biophysical research communications》2007,364(2):220-225
Nanosecond electric pulses generate nanopores in the interior membranes of cells and modulate cellular functions. Here, we used confocal microscopy and flow cytometry to observe Smith antigen antibody (Y12) binding to nuclear speckles, known as small nuclear ribonucleoprotein particles (snRNPs) or intrachromatin granule clusters (IGCs), in Jurkat cells following one or five 10 ns, 150 kV/cm pulses. Using confocal microscopy and flow cytometry, we observed changes in nuclear speckle labeling that suggested a disruption of pre-messenger RNA splicing mechanisms. Pulse exposure increased the nuclear speckled substructures by ∼2.5-fold above basal levels while the propidium iodide (PI) uptake in pulsed cells was unchanged. The resulting nuclear speckle changes were also cell cycle dependent. These findings suggest that 10 ns pulses directly influenced nuclear processes, such as the changes in the nuclear RNA-protein complexes. 相似文献
170.