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The appropriate regulation of retinoic acid signaling is indispensable for patterning of the vertebrate central nervous system along the anteroposterior (A-P) axis. Although both CYP26A1 and CYP26C1, retinoic acid-degrading enzymes that are expressed at the anterior end of the gastrulating mouse embryo, have been thought to play an important role in central nervous system patterning, the detailed mechanism of their contribution has remained largely unknown. We have now analyzed CYP26A1 and CYP26C1 function by generating knockout mice. Loss of CYP26C1 did not appear to affect embryonic development, suggesting that CYP26A1 and CYP26C1 are functionally redundant. In contrast, mice lacking both CYP26A1 and CYP26C1 were found to manifest a pronounced anterior truncation of the brain associated with A-P patterning defects that reflect expansion of posterior identity at the expense of anterior identity. Furthermore, Cyp26a1-/-Cyp26c1-/- mice fail to produce migratory cranial neural crest cells in the forebrain and midbrain. These observations, together with a reevaluation of Cyp26a1 mutant mice, suggest that the activity of CYP26A1 and CYP26C1 is required for correct A-P patterning and production of migratory cranial neural crest cells in the developing mammalian brain.  相似文献   
84.

Background

The efficacy of physical exercise as an augmentation to pharmacotherapy with antidepressants for depressive patients has been documented. However, to clarify the effectiveness of exercise in the treatment of depression, it is necessary to distinguish the effect of the exercise itself from the effect of group dynamics. Furthermore, an objective measurement for estimation of the effect is needed. Previous reports adopted a series of group exercises as the exercise intervention and mainly psychometric instruments for the measurement of effectiveness. Therefore, this clinical study was done to examine the effectiveness of a single session of individual exercise on depressive symptoms by assessing the change in saliva free cortisol level, which reflects hypothalamic-pituitary-adrenocortical axis function that is disturbed in depressive patients.

Method

Eighteen medicated patients, who met the DSM-IV-TR criteria for major depressive disorder, were examined for the change in saliva free cortisol levels and the change in subjective depressive symptoms before and after pedaling a bicycle ergometer for fifteen minutes. Within a month after the exercise session, participants conducted a non-exercise control session, which was sitting quietly at the same time of day as the exercise session.

Results

Depressed patients who participated in this study were in remission or in mild depressive state. However, they suffered chronic depression and had disturbed quality of life. The saliva free cortisol level and subjective depressive symptoms significantly decreased after the exercise session. Moreover, the changes in these variables were significantly, positively correlated. On the other hand, although the subjective depressive symptoms improved in the control session, the saliva free cortisol level did not change.

Conclusion

For the first time in depressive patients, we were able to show a decrease in the saliva free cortisol level due to physical exercise, accompanied by the improvement of subjective depressive symptoms. This identified a possible influence of exercise on the hypothalamic-pituitary-adrenal axis in depression.These results suggest the utility of assessing the effect of physical exercise by saliva free cortisol level in depressive patients who suffer from bio-psycho-social disability.
  相似文献   
85.
Culex tritaeniorhynchus rhabdovirus (CTRV) is a mosquito virus that establishes persistent infection without any obvious cell death. Therefore, occult infection by CTRV can be present in mosquito cell lines. In this study, it is shown that NIID‐CTR cells, which were derived from Cx. tritaeniorhynchus, are persistently infected with a novel strain of CTRV. Complete genome sequencing of the infecting strain revealed that it is genetically similar but distinct from the previously isolated CTRV strain, excluding the possibility of contamination. These findings raise the importance of further CTRV studies, such as screening of CTRV in other mosquito cell lines.  相似文献   
86.
We previously reported that a soluble CD14-subtype (sCD14-ST) immunochromatographic test (ICT) for plasma is more convenient than chemiluminescent enzyme immunoassay (CLEIA), but plasma separation makes bedside measurements difficult. We developed a new sCD14-ST ICT for whole blood and investigated whether quantitative determinations of sCD14-ST by ICT were useful for diagnosing sepsis and severe sepsis/septic shock. We studied 20 patients who fulfilled two or more systemic inflammatory response syndrome (SIRS) criteria and 32 patients who had been diagnosed with sepsis or severe sepsis/septic shock. Whole blood was collected on day 0 (on admission) and day 7, and the sCD14-ST concentration was quantitatively measured by CLEIA and ICT for whole blood. The patients’ Acute Physiology and Chronic Health Evaluation (APACHE) II, Sequential Organ Failure Assessment (SOFA), and Mortality in Emergency Department Sepsis (MEDS) scores were also calculated. The cut-off values obtained by the quantitative measurements made by ICT were 464.5 pg/mL for sepsis and 762.7 pg/mL for severe sepsis/septic shock (P < 0.0001). A Bland–Altman plot showed that no fixed bias or proportional bias was detected between CLEIA and quantitative ICT for whole blood. sCD14-ST concentrations were significantly correlated with APACHE II, SOFA, and MEDS scores (P < 0.0001). These results suggest that the new sCD14-ST ICT for whole blood may be a useful tool for the convenient, rapid bedside diagnosis and treatment of sepsis.  相似文献   
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Saito  On  Kobayashi  Tatsuya  Hiroi  Maiko  Kawatsu  Masayuki  Takagi  Shun  Nishihiro  Jun  Kagami  Maiko 《Limnology》2019,20(1):21-28
Limnology - Trapa spp. dominate many shallow eutrophic lakes in Japan, which must affect the nutrient dynamics in lakes. Trapa spp. are utilized by several animals, in particular the leaf beetle,...  相似文献   
89.
The mechanisms underlying physiological regulation of alloimmune responses remain poorly defined. We investigated the roles of cytokines, CTLA-4, CD25(+) T cells, and apoptosis in regulating alloimmune responses in vivo. Two murine cardiac transplant models were used, B10.D2 (minor mismatch) and C57BL/6 (major mismatch), into BALB/c recipients. Recipients were wild type, STAT4(-/-) (Th1 deficient), or STAT6(-/-) (Th2 deficient) mice. Minor mismatched allografts were accepted spontaneously in approximately 70% of wild type and STAT4(-/-) mice. By contrast, there was significantly shorter graft survival in minor mismatched STAT6(-/-) mice. Either the adoptive transfer of STAT4(-/-) splenocytes or the administration of IL-4Fc fusion protein into STAT6(-/-) mice resulted in long term graft survival. Blocking CTLA-4 signaling accelerated the rejection in all recipients, but was more pronounced in the minor combination. This was accompanied by an increased frequency of alloreactive T cells. Furthermore, CTLA-4 blockade regulated CD4(+) or CD8(+) as well as Th1 or Th2 alloreactive T cells. Finally, while anti-CD25 treatment prolonged graft survival in the major mismatched combination, the same treatment accelerated graft rejection in the minor mismatched group. The latter was associated with an increased frequency of alloreactive T cells and inhibition of T cell apoptosis. These data demonstrate that cytokine regulation, CTLA-4 negative signaling, and T cell apoptosis play critical roles in regulating alloimmunity, especially under conditions where the alloreactive T cell clone size is relatively small.  相似文献   
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