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91.
ABSTRACT

Chemotherapy administration may result in the disruption of circadian rhythms and impairment of quality of life (QoL) of cancer patients. Nevertheless, we have little knowledge on the long-term consequences of chemotherapy and the effects of hospitalization. In the present study, we employed the two-factor repeated-measure cross-sectional design to determine the effects of chemotherapy and hospitalization on rest-activity (RA) rhythm and QoL of breast cancer patients. Initially, we randomly selected 39 inpatients and 42 outpatients, scheduled to receive six cycles of chemotherapy, from the Regional Cancer Center (RCC), Raipur, India. Finally, 30 patients in each group were included in the current study. We monitored circadian RA rhythm and QoL using wrist actigraphy and QLQ-C30 and QLQ-BR23, respectively, during the 1st (C1), 3rd (C3) and 6th (C6) chemotherapy cycles. Results revealed that with the progression of chemotherapy cycles (from C1 to C6), all rhythm parameters, namely mesor, amplitude, acrophase, rhythm quotient (RQ), circadian quotient (CQ), peak activity (PA), dichotomy index and autocorrelation coefficient, significantly decreased in both cancer in- and outpatients. In both groups of patients and during C1–C6, all functional and global QoL measures of QLQ-C30 and QLQ-BR23 significantly decreased and the symptoms significantly increased, except constipation, body image, sexual functioning and future perspectives in outpatients. The hospitalization exacerbated the problems associated with the RA rhythm and the QoL of the patients. In conclusion, the current study highlighted the negative consequences of hospitalization among inpatients, irrespective of the stage of cancer. We, therefore, recommend that cancer patients should be administered with chemotherapy as outpatients. The proposed protocol might have a covert bearing on the expression of better physiological state leading to satisfactory treatment outcomes.  相似文献   
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Promising directions in plant phenotypic plasticity   总被引:9,自引:0,他引:9  
A research agenda for the next phase of plasticity studies calls for contributions from a diverse group of biologists, working both independently and collaboratively, to pursue four promising directions: examining dynamic, anatomical/architectural, and cross-generational plasticity along with simpler growth traits; carefully assessing the adaptive significance of those plasticity patterns; investigating the intricate transduction pathways that lead from environmental signal to phenotypic response; and considering the rich environmental context of natural systems. Progress in these areas will allow us to address broad and timely questions regarding the ecological and evolutionary significance of plasticity and the nature of phenotypic determination.  相似文献   
95.
SHP (short heterodimer partner) is an orphan nuclear receptor, first described for its interaction with nuclear receptors. This study explores a new way of inhibiting the androgen-signaling pathway. We demonstrated that SHP inhibited up to 97% of AR-induced activity. Characterization of AR/SHP interaction provided evidence of a clear ligand dependency. We also showed that the LXXI/LL motifs previously found on SHP mediated the interaction with the AR ligand-binding domain (AR-LBD), the motif responsible for the interaction being slightly different from that found with ER. The AR N-terminal domain (AR-NTD), in contrast to that of other nuclear receptors, accounts for most of the entire receptor transactivation potential. SHP also interacted with AR-NTD, thus stabilizing the interaction with AR. We demonstrated that SHP inhibited both AR-LBD and NTD-dependent transactivation, which evidenced for the first time a protein capable of inhibiting a steroid receptor amino-terminal-dependent transactivation. We further characterized the SHP mechanism of action by showing that SHP reversed AR coactivator-mediated activation. Conversely, FHL2 and TIF2 counteracted SHP-mediated inhibition of AR. SHP evidences a new way of inhibiting AR activity by competing with AR coactivators. This new type of inhibitor could dictate the activity of nuclear receptors, depending on the equilibrium between activators and inhibitors.  相似文献   
96.
In 90%-hepatectomized rats, the plasma testosterone level (0.34 +/- 0.07 ng.ml, mean +/- SEM) is significantly lower (P less than 0.001) than in sham operated male rats (1.7 +/- 0.26 ng.ml, mean +/- SEM). In dogs, after 90% hepatectomy, the mean plasma testosterone concentration fell to 1/10 of the plasma testosterone level measured in sham operated animals either 24 or 72 h after surgery. In hepatectomized men, plasma testosterone is markedly decreased in contrast to what is observed after duodeno-pancreatectomy performed under the same conditions of anesthesia. These results suggest that 90% hepatectomy severely alters the Leydig cell function.  相似文献   
97.
Haloxylon persicum (Bunge ex Boiss & Buhse), is one of the hardy woody desert shrubs, which is now endangered and/or nearing extinction. Urban landscape development and overgrazing are the major threats for the erosion of this important plant species. For conserving the species, it is critical to develop an efficient in vitro regeneration protocol for rapid multiplication of large number of regenerants. Leaf explants, cultured on Murashige and Skoog (MS) medium supplemented with different concentrations of thidiazuron (TDZ) (0.5, 1, 2 µM), showed significant difference in bud sprouting and adventitious shoot induction. The highest shoot bud formation was recorded on MS medium supplemented with 0.5 µM TDZ. Shoot tip necrosis (STN), observed after first subculture of shoot buds in same medium, increased in severity with subculture time. Application of calcium (4 mM) and boron (0.1 mM) in combination with kinetin (10 µM) in the subculture medium significantly reduced the intensity of STN. On an average eight shoots/explant were produced by alleviating this problem. ISSR marker analysis revealed monomorphic banding pattern between progenies and parents, indicating the true to type nature of the clones and its parents.  相似文献   
98.
Retinitis pigmentosa (RP) is the most frequent genetically and clinically heterogeneous inherited retinal degeneration. To date, more than 80 genes have been identified that cause autosomal dominant, autosomal recessive and X linked RP. However, locus and allelic heterogeneity of RP has not been fully captured yet. This heterogeneity and lack of an accurate genotype phenotype correlation makes molecular dissection of the disease more difficult. The present study was designed to characterize the underlying pathogenic variants of RP in Pakistan. For this purpose, a large consanguineous family with RP phenotype showing autosomal recessive mode of inheritance was selected after a complete ophthalmological examination. Next generation sequencing was used for the identification of molecular determinant followed by Sanger-sequencing for confirmation. After sequence analysis a novel homozygous missense mutation, (c.602 C?>?T) in exon 4 of the RDH5 gene (MIM: 601617) was identified. This mutation resulted in substitution of phenyl alanine for serine at amino acid 201 (p.Ser201Phe) of the RDH5 gene. The same mutation was not detected in the 200 ethnically-matched control samples by Sanger sequencing. The identified mutant allele segregated in homozygous fashion in all the affected individuals of pedigree. Identification of this mutation reveals the allelic heterogeneity of RDH5 in patients with RP phenotype. The findings of this study demonstrate the clinical significance of next generation sequencing to understand the molecular basis of diseases and would help to reveal new proteins and their function in visual cycle will pave the way for early diagnosis, genetic counseling and better therapeutic inventions.  相似文献   
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100.
Summary Lymphoblastoid cell lines (LCLs) derived from two patients identified as ataxia telangiectasia (AT), two obligate AT heterozygotes and two controls (healthy subjects with no known genetic disease or relationship to AT patients) were compared with respect to the induction of chromosomal breaks by acute and chronic -irradiation. Although there was a considerable increase in the frequency of chromosomal breaks per cell in the LCLs of AT patients resulting from acute irradiation, the small increase occurring in the LCLs of the AT heterozygotes made it difficult to distinguish them from the controls. Following chronic -irradiation, however, the frequency of chromosomal breaks per cell in the LCLs of the AT heterozygotes occupied a significantly distinct position from that of the controls. These observations suggested that the use of chronic irradiation may be a better choice in the cytogenetic characterization of AT heterozygotes.  相似文献   
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