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131.
The cyclin-dependent kinase inhibitor 3 (CDKN3) gene, involved in mitosis, is upregulated in cervical cancer (CC). We investigated CDKN3 mRNA as a survival biomarker and potential therapeutic target for CC. CDKN3 mRNA was measured in 134 CC and 25 controls by quantitative PCR. A 5-year survival study was conducted in 121 of these CC patients. Furthermore, CDKN3-specific siRNAs were used to investigate whether CDKN3 is involved in proliferation, migration, and invasion in CC-derived cell lines (SiHa, CaSki, HeLa). CDKN3 mRNA was on average 6.4-fold higher in tumors than in controls (p = 8 x 10−6, Mann-Whitney). A total of 68.2% of CC patients over expressing CDKN3 gene (fold change ≥ 17) died within two years of diagnosis, independent of the clinical stage and HPV type (Hazard Ratio = 5.0, 95% CI: 2.5–10, p = 3.3 x 10−6, Cox proportional-hazards regression). In contrast, only 19.2% of the patients with lower CDKN3 expression died in the same period. In vitro inactivation of CDKN3 decreased cell proliferation on average 67%, although it had no effect on cell migration and invasion. CDKN3 mRNA may be a good survival biomarker and potential therapeutic target in CC.  相似文献   
132.
This letter describes the discovery of a novel series of tetrahydroisoquinoline (THIQ)-derived small molecules that potently inhibit both human T-cell migration and super-antigen induced T-cell activation through disruption of the binding of integrin LFA-1 to its receptor, ICAM-1. In addition to excellent in vitro potency, 6q shows good pharmacokinetic properties and its ethyl ester (6t) demonstrates good oral bioavailability in both mouse and rat. Either intravenous administration of 6q or oral administration of its ethyl ester (6t) produced a significant reduction of neutrophil migration in a thioglycollate-induced murine peritonitis model.  相似文献   
133.
In experiments on the 7-day-old female and male Long-Evans rat pups, for the first time, there was studied effect of prenatal (immobilization) stress on dynamics of nociceptive behavioral response caused by an inflammatory focus. The nociceptive sensitivity was evaluated for 1 h by the number of 7-day-old organized at the spinal level in response to injection of formalin (10%, 10 microl) to the posterior leg sole. Control rat pups were not submitted to any prenatal stress; in these animals the response in the formalin test was found to be represented by one phase. It the prenatally stressed rat pups the studied patterns were organized into two phases characteristic of the definitive type of response. At the period between them (during interphase), the nociceptive behavior was absent. At the second, tonic phase the number of flexes+shakes in the prenatally stressed males was statistically significantly higher than in the prenatally stressed females, which indicates a sensitization of the neurons involved in the tonic pain chains in male individuals. Thus, the data obtained on prenatally stressed animals confirm the previous data about immaturity of the mechanisms mediating the second phase of response in the formalin test in the 7-day-old rat pups. An important fact is revealed which indicates that in the prenatally stressed rat pups of the same age the second phase of response is already obvious. Mechanisms underlying the behavioral response caused by the inflammatory focus in the formalin test in the number flexes + shakes old stressed rat pups are characterized by sexual dimorphism: the pain sensitivity in males at the second phase of response is statistically significantly higher than in females.  相似文献   
134.
The effects of bait treatment(s) on population dynamics of Solenopsis invicta and Dorymyrmex flavus were studied, and various factors underlying the resurgence and persistence of D. flavus to reinvasion by S. invicta were studied in more detail. Pitfall traps, bait vials, transect sampling, and direct inspections were used to monitor densities of these two species, and inspections of D. flavus midden contents, video monitoring of D. flavus colonies, and studies of the fate of marked S. invicta were used to further clarify interactions of these two species, D. flavus abundance increased after the reduction of S. invicta with baits. D. flavus was also observed to sustain higher densities for an extended period (2 yr) after cessation of bait treatment and to exhibit antagonistic behaviors toward S. invicta, showing an ability to resist reinvasion of the treated area by S. invicta. Given these findings, D. flavus may retard domination of the ant assemblage by S. invicta. Additional studies are justified regarding how to enhance the role of this species in affected ecosystems.  相似文献   
135.
An unknown virus was isolated from a lung biopsy sample and multiple other samples from a patient who developed a lethal case of pneumonia following a peripheral blood stem cell transplant. A random PCR-based molecular screening method was used to identify the infectious agent as avian paramyxovirus 1 (APMV-1; a group encompassing Newcastle disease virus), which is a highly contagious poultry pathogen that has only rarely been found in human infections. Immunohistochemical analysis confirmed the presence of APMV-1 antigen in sloughed alveolar cells in lung tissue from autopsy. Sequence from the human isolate showed that it was most closely related to virulent pigeon strains of APMV-1. This is the most completely documented case of a systemic human infection caused by APMV-1 and is the first report of an association between this virus and a fatal disease in a human.  相似文献   
136.
The effects of acute emotional stress on the sympathetic component of the arterial baroreceptor reflex have not yet been described in conscious animals and humans. Arterial pressure (AP) and renal sympathetic nerve activity (RSNA) were simultaneously recorded in 11 conscious rats before and during exposure to a mild environmental stressor (jet of air). Baroreflex function curves relating AP and RSNA were constructed by fitting a sigmoid function to RSNA and AP measured during sequential nitroprusside and phenylephrine administrations. Stress increased mean AP from 112 +/- 2 to 124 +/- 2 mmHg, heart rate from 381 +/- 10 to 438 +/- 18 beats/min, and RSNA from 0.80 +/- 0.14 to 1.49 +/- 0.23 microV. The RSNA-AP relationship was shifted toward higher AP values, and its maximum gain was significantly (P < 0.01) increased from 9.0 +/- 1.3 to 16.2 +/- 2.1 normalized units (NU)/mmHg. The latter effect was secondary to an increase (P < 0.01) in the range of the RSNA variation from 285 +/- 33 to 619 +/- 59 NU. In addition, the operating range of the reflex was increased (P < 0.01) from 34 +/- 2 to 41 +/- 3 mmHg. The present study indicates that in rats, the baroreflex control of RSNA is sensitized and operates over a larger range during emotional stress, which suggests that renal vascular tone, and possibly AP, are very efficiently controlled by the sympathetic nervous system under this condition.  相似文献   
137.
The present study examined whether the gain of the transfer function relating cardiac-related rhythm of renal sympathetic nerve activity (RSNA) to arterial pressure (AP) pulse might serve as a spontaneous index of sympathetic baroreflex sensitivity (BRS). AP and RSNA were simultaneously recorded in conscious rats, either baroreceptor-intact (control, n = 11) or with partial denervation of baroreflex afferents [aortic baroreceptor denervated (ABD; n = 10)] during 1-h periods of spontaneous activity. Transfer gain was calculated over 58 adjacent 61.4-s periods (segmented into 10.2-s periods). Coherence between AP and RSNA was statistically (P < 0.05) significant in 90 +/- 3% and 56 +/- 10% of cases in control and ABD rats, respectively. Transfer gain was higher (P = 0.0049) in control [2.39 +/- 0.13 normalized units (NU)/mmHg] than in ABD (1.48 +/- 0.22 NU/mmHg) rats. In the pooled study sample, transfer gain correlated with sympathetic BRS estimated by the vasoactive drug injection technique (R = 0.75; P < 0.0001) and was inversely related to both time- (standard deviation; R = -0.74; P = 0.0001) and frequency-domain [total spectral power (0.00028-2.5 Hz); R = -0.82; P < 0.0001] indices of AP variability. In control rats, transfer gain exhibited large fluctuations (coefficient of variation: 34 +/- 3%) that were not consistently related to changes in the mean level of AP, heart rate, or RSNA. In conclusion, the transfer function method provides a continuous, functionally relevant index of sympathetic BRS and reveals that the latter fluctuates widely over time.  相似文献   
138.
In comparison with most animal behaviours, circadian rhythms have a well-characterized molecular genetic basis. Detailed studies of circadian clock genes in 'model' organisms provide a foundation for interpreting the functional and evolutionary significance of polymorphic circadian clock genes found within free-living animal populations. Here, we describe allelic variation in a region of the avian Clock orthologue which encodes a functionally significant polyglutamine repeat (ClkpolyQcds), within free-living populations of two passerine birds, the migratory bluethroat (Luscinia svecica) and the predominantly nonmigratory blue tit (Cyanistes caeruleus). Multiple ClkpolyQcds alleles were found within populations of both species (bluethroat: 12 populations, 7 alleles; blue tit: 14 populations, 9 alleles). Some populations of both species were differentiated at the ClkpolyQcds locus as measured by F(ST) and R(ST) values. Among the blue tit, but not bluethroat populations, we found evidence of latitudinal clines in (i) mean ClkpolyQcds repeat length, and (ii) the proportions of three ClkpolyQcds genotype groupings. Parallel analyses of microsatellite allele frequencies, which are considered to reflect selectively neutral processes, indicate that interpopulation allele frequency variation at the ClkpolyQcds and microsatellite loci does not reflect the same underlying demographic processes. The possibility that the observed interpopulation ClkpolyQcds allele frequency variation is, at least in part, maintained by selection for microevolutionary adaptation to photoperiodic parameters correlated with latitude warrants further study.  相似文献   
139.
Although they represent powerful genetic markers in many fields of biology, microsatellites have been isolated in few fungal species. The aim of this study was to assess whether obtaining microsatellite markers with an acceptable level of polymorphism is generally harder from fungi than in other organisms. We therefore surveyed the number, nature and polymorphism level of published microsatellite markers in fungi from the literature and from our own data on seventeen fungal microsatellite-enriched libraries, and in five other phylogroups (angiosperms, insects, fishes, birds and mammals). Fungal microsatellites indeed appeared both harder to isolate and to exhibit lower polymorphism than in other organisms. This appeared to be due, at least in part, to genomic specificities, such as scarcity and shortness of fungal microsatellite loci. A correlation was observed between mean repeat number and mean allele number in the published fungal microsatellite loci. The cross-species transferability of fungal microsatellites also appeared lower than in other phylogroups. However, microsatellites have been useful in some fungal species. Thus, the considerable advantages of these markers make their development worthwhile, and this study provides some guidelines for their isolation.  相似文献   
140.
The prevailing wisdom of the plant mitochondrial genome is that it has very low substitution rates, thus it is generally assumed that nucleotide diversity within species will also be low. However, recent evidence suggests plant mitochondrial genes may harbor variable and sometimes high levels of within-species polymorphism, a result attributed to variance in the influence of selection. However, insufficient attention has been paid to the effect of among-gene variation in mutation rate on varying levels of polymorphism across loci. We measured levels of polymorphism in seven mitochondrial gene regions across a geographically wide sample of the plant Silene vulgaris to investigate whether individual mitochondrial genes accumulate polymorphisms equally. We found that genes vary significantly in polymorphism. Tests based on coalescence theory show that the genes vary significantly in their scaled mutation rate, which, in the absence of differences among genes in effective population size, suggests these genes vary in their underlying mutation rate. Further evidence that among-gene variance in polymorphism is due to variation in the underlying mutation rate comes from a significant positive relationship between the number of segregating sites and silent site divergence from an outgroup. Contrary to recent studies, we found unconvincing evidence of recombination in the mitochondrial genome, and generally confirm the standard model of plant mitochondria characterized by low substitution rates and no recombination. We also show no evidence of significant variation in the strength or direction of selection among genes; this result may be expected if there is no recombination. The present study provides some of the most thorough data on plant mitochondrial polymorphism, and provides compelling evidence for mutation rate variation among genes. The study also demonstrates the difficulty in establishing a null model of mitochondrial genome polymorphism, and thus the difficulty, in the absence of a comparative approach, in testing the assumption that low substitution rates in plant mitochondria lead to low polymorphism.  相似文献   
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