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31.
Similarities between New World and Old World vultures have been interpreted to reflect a close relationship and to suggest the inclusion of both in Accipitridae (Falconiformes). However, deeper analyses indicated that the placement of the New World vultures (cathartids) in this Order is uncertain. Chromosome analysis has shown that cathartids retained a karyotype similar to the putative avian ancestor. In order to verify the occurrence of intrachromosomal rearrangements in cathartids, we hybridized whole chromosome probes of two species (Gallus gallus and Leucopternis albicollis) onto metaphases of Cathartes aura. The results showed that not only were the syntenic groups conserved between Gallus and C. aura, but probably also the general gene order, suggesting that New World vultures share chromosomal symplesiomorphies with most bird lineages.  相似文献   
32.
Calcium-calmodulin/dependent protein kinase II (CaMKII), AMP-activated protein kinase (AMPK), and extracellular signal-regulated kinase (ERK1/2) have each been implicated in the regulation of substrate metabolism during exercise. The purpose of this study was to determine whether CaMKII is involved in the regulation of FA uptake and oxidation and, if it is involved, whether it does so independently of AMPK and ERK1/2. Rat hindquarters were perfused at rest with (n = 16) or without (n = 10) 3 mM caffeine, or during electrical stimulation (n = 14). For each condition, rats were subdivided and treated with 10 muM of either KN92 or KN93, inactive and active CaMKII inhibitors, respectively. Both caffeine treatment and electrical stimulation significantly increased FA uptake and oxidation. KN93 abolished caffeine-induced FA uptake, decreased contraction-induced FA uptake by 33%, and abolished both caffeine- and contraction-induced FA oxidation (P < 0.05). Caffeine had no effect on ERK1/2 phosphorylation (P > 0.05) and increased alpha(2)-AMPK activity by 68% (P < 0.05). Electrical stimulation increased ERK1/2 phosphorylation and alpha(2)-AMPK activity by 51% and 3.4-fold, respectively (P < 0.05). KN93 had no effect on caffeine-induced alpha(2)-AMPK activity, ERK1/2 phosphorylation, or contraction-induced ERK1/2 phosphorylation (P > 0.05). Alternatively, it decreased contraction-induced alpha(2)-AMPK activity by 51% (P < 0.05), suggesting that CaMKII lies upstream of AMPK. These results demonstrate that regulation of contraction-induced FA uptake and oxidation occurs in part via Ca(2+)-independent activation of ERK1/2 as well as Ca(2+)-dependent activation of CaMKII and AMPK.  相似文献   
33.
Between March and May 2006, a Texas hospital identified five Mycobacterium mucogenicum bloodstream infections among hospitalized oncology patients using fluorescence high-performance liquid chromatography analysis of mycolic acids. Isolates from blood cultures were compared to 16 isolates from environmental sites or water associated with this ward. These isolates were further characterized by hsp65, 16S rRNA, and rpoB gene sequencing, hsp65 PCR restriction analysis, and molecular typing methods, including repetitive element PCR, random amplified polymorphic DNA PCR, and pulsed-field gel electrophoresis (PFGE) of large restriction fragments. Three of five patient isolates were confirmed as M. mucogenicum and were in a single cluster as determined by all identification and typing methods. The remaining two patient isolates were identified as different strains of Mycobacterium phocaicum by rpoB sequence analysis. One of these matched an environmental isolate from a swab of a hand shower in the patient's room, while none of the clinical isolates of M. mucogenicum matched environmental strains. Among the other 15 environmental isolates, 11 were identified as M. mucogenicum and 4 as M. phocaicum strains, all of which were unrelated by typing methods. Although the 16S rRNA gene sequences matched for all 14 M. mucogenicum isolates, there were two each of the hsp65 and rpoB sequevars, seven PCR typing patterns, and 12 PFGE patterns. Among the seven M. phocaicum isolates were three 16S rRNA sequevars, two hsp65 sequevars, two rpoB sequevars, six PCR typing patterns, and six PFGE patterns. This outbreak represents the first case of catheter-associated bacteremia caused by M. phocaicum and the first report of clinical isolates from a U.S. hospital. The investigation highlights important differences in the available typing methods for mycobacteria and demonstrates the genetic diversity of these organisms even within narrow confines of time and space.  相似文献   
34.

Background

To investigate the prevalence of depression, suicidal ideations, alcohol and nicotine consumption in adults in an agrarian society mostly unchanged by the effects of urbanization.

Methods

The Central India Eye and Medical Study is a population-based study in rural Central India close to the tribal belt and included 4711 subjects (aged 30+ years). Depression was assessed by the Center for Epidemiologic Studies Depression Scale (CESD), suicidal ideation by six standardized questions, nicotine use by the Fagerstroem Nicotine Tolerance Questionnaire (FTNQ), and alcohol consumption by the Alcohol Use Disorders Identification Test (AUDIT).

Results

Mild to moderate depression (CESD sum score: 15–21) was detected in 1862 (39.6%) individuals (33.5% of men, 44.8 of women), and major depression (CESD sum score >21) in 613 (13.0%) individuals (8.1 of men, 17.3% of women). Suicide attempt was reported by 199 (4.2%) participants and suicidal thoughts during the last 6 months by 238 (5.1%) individuals. There were 887 (18.9%) smokers and smokeless tobacco was consumed by 1968 (41.8%) subjects. Alcohol consumption was reported by 1081 (23.0%) participants; 283 (6.0%) subjects had an AUDIT score ≥8 (hazardous drinking), and 108 (4.63%) subjects a score ≥13 (women) or ≥15 (men) (alcohol dependence).

Conclusions

In rural Central India, prevalence of major depression was comparable to figures reported from other developing countries. Prevalence of smoking and hazardous alcohol consumption was higher than as reported from urban regions. Measures should be taken to address the relatively high prevalence of suicide attempts and thoughts on suicide in rural Central India.  相似文献   
35.
Evolutionary theory and observation predict wider phenotypic variation in hybrids than parental species. Emergent phenotypic novelty in hybrids may in turn drive new adaptations or speciation by breaking parental phenotypic constraints. Primate hybridization is often documented through genetic evidence, but knowledge about the primate hybrid phenotype remains limited due to a small number of available studies on hybrid primate morphology. Here, we examine pelage and morphometric variation in two Brazilian marmoset species (Callithrix penicillata and C. geoffroyi) and their hybrids. Hybrids were sampled in an anthropogenic hybrid zone in the municipality of Viçosa, Minas Gerais state, Brazil. We analyzed hybrid facial and body pelage color variation, and compared 13 morphometric measures between hybrids and parental species. Five different hybrid facial morphotypes were observed, varying from intermediate to parental-like. Hybrid facial morphotypes were biased towards C. penicillata, suggesting that the pelage of this species may be dominant to that of C. geoffroyi in this context, and indicating that mate preference, and therefore gene flow/introgression, may be biased towards C. penicillata within the hybrid zone. Hybrid morphometric features were on average intermediate to parental species traits, but transgressive hybrids were also observed, suggesting that morphometric variation for the studied traits is consistent with Rieseberg’s complementary allele model. Finally, we observed a decoupling of facial patterning and size/shape in hybrids, relative to parent phenotypes, suggesting that an important factor driving phenotypic novelty within the Viçosa marmoset hybrid zone might be the loosening of evolutionary constraints on phenotypic trait integration.  相似文献   
36.
Summary— Immunofluorescence and immunoelectron microscopy indicated that the antibody raised against the nuclear antigen Ki-67 of mammalian cells recognized antigenic determinants of early Drosophila embryos, localized on the outside of the nuclear envelope. Hence, the nuclear envelope of Drosophila appears to share a similar epitope with the chromosome scaffold of mitotic mammalian cells. With the progression of mitosis the antigen persisted around the mitotic spindle region and was also found in the pole regions at metaphase and anaphase. The antibody also stained the equatorial regions of the spindles from anaphase to late telophase. The antibody may therefore be used as a biochemical marker of the nuclear envelope for studying nuclear membrane biogenesis and behavior during the mitotic divisions of the Drosophila embryo.  相似文献   
37.
IMP preferring cytosolic 5 ′-nucleotidase II (cN-II) is a widespread enzyme whose amino acid sequence is highly conserved among vertebrates. Fluctuations of its activity have been reported in some pathological conditions and its mRNA levels have been proposed as a prognostic factor for poor outcome in patients with adult acute myeloid leukemia. As a member of the oxypurine cycle, cN-II is involved in the regulation of intracellular concentration of 5′-inosine monophosphate (IMP), 5′-guanosine monophosphate (GMP), and also 5-phosphoribose 1-pyrophosphate (PRPP) and is therefore involved in the regulation of purine and pyrimidine de novo and salvage synthesis. In addition, several studies demonstrated the involvement of cN-II in pro-drug metabolism. Notwithstanding some publications indicating that cN-II is essential for the survival of several cell types, its role in cell metabolism remains uncertain. To address this issue, we built two eucaryotic cellular models characterized by different cN-II expression levels: a constitutive cN-II knockdown in the astrocytoma cell line (ADF) by short hairpin RNA (shRNA) strategy and a cN-II expression in the diploid strain RS112 of Saccharomyces cerevisiae. Preliminary results suggest that cN-II is essential for cell viability, probably because it is directly involved in the regulation of nucleotide pools. These two experimental approaches could be very useful for the design of a personalized chemotherapy.  相似文献   
38.
Cotyledons were excised from imbibed watermelon seeds, grown for 4 days in darkness on water or 10 M benzyladenine (BA) and then tested for the presence of the light-harvesting chlorophyll a/b protein (LHCP) and its mRNA. LHCP was assayed immunologically by western blotting of SDS gels: the protein was present in plastids, but it was not recovered with the thylakoid fraction. Antibodies directed against LHCP precipitated a 32 kDa polypeptide from translation products of poly(A) RNA of cotyledons only if these had been grown on BA. Taken together the data suggest that in absence of light cytokinins are necessary for the maintenance of a detectable level of LHCP-mRNA as well as for synthesis of the protein.  相似文献   
39.
40.

Background  

Occupational and chronic exposure to solvents and metals is considered a possible risk factor for Parkinson's disease and essential tremor. While manufacturing dental prostheses, dental technicians are exposed to numerous chemicals that contain toxins known to affect the central nervous system, such as solvents (which contain n-hexane in particular) and metals (which contain mercury, iron, chromium, cobalt and nickel).  相似文献   
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