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Booknotes     
MR 《Biology & philosophy》1987,2(1):117-122
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3.
Multiple sclerosis (MS) is a demyelinating disease that affects the central nervous system. MS is the most common neurological disorder in young adults with a greater incidence among females. Male gonadal hormones have a protective effect on neural system development and myelin maturation. In this study, we investigate the effect of castration on lysolecithin-induced demyelination and remyelination processes using visual evoked potentials, in addition to measuring the expressions of Olig2, MBP, Nogo-A and GFAP mRNAs as oligodendrocyte or astrocyte markers; and histological assessments by myelin-specific staining. We observed more expanded demyelination with delayed repair process in castrated rats. Expression levels of the aforementioned marker genes confirmed histological and electrophysiological observations. Our results showed a pivotal role for endogenous male hormones in the context of demyelinating insults. It may also account for the different prognosis of MS between male and female genders and provide new insights for therapeutic treatments.  相似文献   
4.

Introduction

Exercise training has emerged as a promising therapeutic strategy to counteract physical dysfunction in adult systemic lupus erythematosus. However, no longitudinal studies have evaluated the effects of an exercise training program in childhood-onset systemic lupus erythematosus (C-SLE) patients. The objective was to evaluate the safety and the efficacy of a supervised aerobic training program in improving the cardiorespiratory capacity in C-SLE patients.

Methods

Nineteen physically inactive C-SLE patients were randomly assigned into two groups: trained (TR, n = 10, supervised moderate-intensity aerobic exercise program) and non-trained (NT, n = 9). Gender-, body mass index (BMI)- and age-matched healthy children were recruited as controls (C, n = 10) for baseline (PRE) measurements only. C-SLE patients were assessed at PRE and after 12 weeks of training (POST). Main measurements included exercise tolerance and cardiorespiratory measurements in response to a maximal exercise (that is, peak VO2, chronotropic reserve (CR), and the heart rate recovery (ΔHRR) (that is, the difference between HR at peak exercise and at both the first (ΔHRR1) and second (ΔHRR2) minutes of recovery after exercise).

Results

The C-SLE NT patients did not present changes in any of the cardiorespiratory parameters at POST (P > 0.05). In contrast, the exercise training program was effective in promoting significant increases in time-to-exhaustion (P = 0.01; ES = 1.07), peak speed (P = 0.01; ES = 1.08), peak VO2 (P = 0.04; ES = 0.86), CR (P = 0.06; ES = 0.83), and in ΔHRR1 and ΔHRR2 (P = 0.003; ES = 1.29 and P = 0.0008; ES = 1.36, respectively) in the C-SLE TR when compared with the NT group. Moreover, cardiorespiratory parameters were comparable between C-SLE TR patients and C subjects after the exercise training intervention, as evidenced by the ANOVA analysis (P > 0.05, TR vs. C). SLEDAI-2K scores remained stable throughout the study.

Conclusion

A 3-month aerobic exercise training was safe and capable of ameliorating the cardiorespiratory capacity and the autonomic function in C-SLE patients.

Trial registration

NCT01515163.  相似文献   
5.
The current status of kinetoplastids phylogeny and evolution is discussed in view of the recent progresses on genomics. Some ideas on a potential framework for the evolutionary genomics of kinetoplastids are presented.  相似文献   
6.

Introduction

While NTM infection is mainly acquired from environmental exposure, monitoring of environmental niches for NTM is not a routine practice. This study aimed to find the prevalence of environmental NTM in soil and water in four highly populated suburbs of Tehran, Iran.

Material and Methods

A total of 4014 samples from soil and water resources were collected and studied. Sediments of each treated sample were cultured in Lowenstein-Jensen medium and observed twice per week for growth rate, colony morphology, and pigmentation. Colonies were studied with phenotypic tests. Molecular analysis was performed on single colonies derived from subculture of original isolates. Environmental samples were compared with 34 NTM isolates from patients who were residents of the study locations.

Results

Out of 4014 samples, mycobacteria were isolated from 862 (21.4%) specimens; 536 (62.1%) belonged to slow growing mycobacteria (SGM) and 326 (37.8%) were rapid growing mycobacteria (RGM). The five most frequent NTM were M. farcinogens (105/862; 12.1%), M. fortuitum (72/862; 8.3%), M. senegalense (58/862; 6.7%), M. kansasii (54/862; 6.2%), and M. simiae (46/862; 5.3%). In total, 62.5% (539/862) of mycobacterial positive samples were isolated from water and only 37.4% (323/862) of them were isolated from soil samples (P<0.05). Out of 5314 positive clinical samples for mycobacteria, 175 (3.2%) isolates were NTM. The trend of NTM isolates increased from 1.2% (13 out of 1078) in 2004 to 3.8% (39 out of 1005) in 2014 (P = 0.0001). The major clinical isolates were M. simiae (51; 29.1%), M. kansasii (26; 14.8%), M. chelonae (28; 16%), and M. fortuitum (13; 7.4%).

Conclusions

Comparing the distribution pattern of environmental NTM isolates with clinical isolates suggests a possible transmission link, but this does not apply to all environmental NTM species. Our study confirms an increasing trend of NTM isolation from clinical samples that needs further investigation.  相似文献   
7.
Molecular Biology Reports - Neuroinflammation and mitochondrial dysfunction are suggested as mechanisms which are implicated in the pathophysiology of depression. Streptozotocin (STZ) is known to...  相似文献   
8.
Grape softwood cuttings of Khoshnaw cultivar were cultured using tissue-culture methods to study the effect of iron nanoparticles and potassium silicate under salinity conditions during the 2015–2016 growing season. The treatments consisted of salinity stress (0, 50, and 100 mM NaCl), nanoparticles of iron (0, 0.08, and 0.8 ppm), and potassium silicate (0, 1, 2 mM). The results also showed that the application of iron nanoparticles and potassium silicate significantly increased the total protein content and reduced proline, enzymatic antioxidant activity and hydrogen peroxide. Salinity stress reduced membrane stability index while increased malondialdehyde content. Increase of membrane stability index and reduction of malondialdehyde content were obtained for 2 mM potassium silicate and 0.8 ppm iron nanoparticle. Iron and potassium silicate were shown to lower the sodium content and increase the potassium content under salinity-stress conditions. The highest ratio of sodium to potassium was observed in plants under salinity conditions (100 mM) treated with neither iron nanoparticles nor potassium silicate; conversely, the lowest ratio was achieved in plants treated with both 0.8 ppm iron nanoparticles with 1 mM and 2 mM potassium silicate under non-stress conditions. These results indicate that the application of micronutrients in stressful conditions is a suitable method to compensate for the negative effects of salinity stress. Tissue culture in this study was shown to be an economically efficient and applicable technique for producing grape softwood cuttings to be used in experiments.  相似文献   
9.
Vascular endothelial growth factor (VEGF) has long been recognized as a hypotensive mediator. Little is known regarding the contribution of polymorphisms in VEGF gene to essential hypertension (EH), however. We aimed to investigate the association between +405 VEGF C/G single nucleotide polymorphism (SNP) and occurrence of EH in a sample of patients with diabetes. A study population of 474 subjects with diabetes of which 45.6% (216) had EH was enrolled in this study. Interviews and physical examinations were performed in a clinical setting. Subjects were matched in baseline anthropometric and biochemical characteristics except for total cholesterol. Genotyping of +405 VEGF C/G (rs2010963) SNP was carried out using polymerase chain reaction–restriction fragment length polymorphism. The allelic distribution of the sample did not violate Hardy–Weinberg equilibrium. Subjects with EH had a higher frequency of G allele (P = 0.005). Additionally, those with EH had a significantly higher frequency of GG genotype (P = 0.015). In multivariate logistic regression models controlling for possible confounders, having GG against CC genotype was associated with an odds ratio of 2.51 (95% CI: 1.44–4.38; P = 0.001). Moreover, presence of each G allele was linked to a 1.58-fold increase in risk of having EH (95% CI: 1.200–2.086; P = 0.001). In conclusion, +405 VEGF C/G SNP is associated with EH in patients with diabetes, suggesting presence of G allele and GG or CG genotype confer susceptibility towards EH.  相似文献   
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