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11.
Various studies have described glycyrrhizin (GL), an active triterpenoic saponin extract of licorice roots, as an anti-inflammatory, antiviral, antimicrobial, anti-tumor and immunomodulating agent. The activity of GL has been mainly attributed to its metabolites, 18-alpha (GA) and 18-beta-glycyrrhetinic acid (GB), which their mechanism of action on the immune system cells is not clearly known. In this study, we have investigated the effects of GA and GB on the immune system by targeting dendritic cells and analyzing phenotypic and functional maturity of murine dendritic cells (DCs) after treatment with these components. Stimulation of DCs with GA and GB resulted in up-regulation of CD40, CD86 and MHC-II molecules indicating their effects on the maturation of DCs. These components induced the allogenic immunostimulatory capacity of DCs by stimulating the proliferation of T cells and production of the T helper (h)1-promoting cytokine, IL-12. They also increased the production of IFN-γ by T cells in mixed-lymphocyte reaction. In conclusion, these results indicate that GA and GB may insert their immunomodulatory effects by enhancing DC maturation and modulating Th1/Th2 response through an increase in Th1 responses, implying their beneficial in host defense against infectious diseases.  相似文献   
12.
The COVID-19 pandemic has struck nations worldwide, pushing worldwide health and socioeconomic systems to extreme limits. Various factors, such as drastic alterations in public environments, prolonged quarantine, revenue loss, and anxiety of disease contraction, have caused mental turmoil. Although there was a need to cope with an excess of psychological strain among the public, post-COVID patients, and those with a previously diagnosed psychiatric condition, mental health programs faced a substantial decline in services, mirroring the dramatic rise in psychological issues. Interestingly, certain coping strategies play protective or deleterious effects on mental health outcomes. Moreover, social media exposure has played a double-edged role in the mental health of the public during the pandemic, leaving grounds for further debates. Protean cultural themes have taken center stage in the discussion on social resilience and compliance to COVID-19 measures, driving their impact through certain work ethics, social capital, and public attitudes in different societies. On the other hand, exceedingly rising poverty rates cemented the deleterious economic impact of the pandemic. Attention has been called to the racial implications of the pandemic, driving millions of individuals with low socioeconomic position (SEP) and belonging to minority groups out of the paid workforce. Interestingly, we turn attention to an array of elements implicated in this dramatic effect, such as public transport, living arrangements, and health insurance coverage among these vulnerable groups. We attempt to address the mechanisms COVID-19 channeled its mental health and socioeconomic impacts by explaining the risk factors and pave the way for stronger crisis management in the future by evaluating the socioeconomic and psychological effects in stark detail.  相似文献   
13.

Background

Bearing surface wear and osteolysis are major factors limiting the durability of total hip arthroplasty (THA). Second generation annealed highly cross-linked polyethylene (HXLPE) and ceramics were introduced to THA for their excellent wear rates. However, there is little data comparing the wear rates of metal and ceramic heads on second generation HXLPE.

Methods

Sixty patients who received a noncemented THA with a 32- or 36-mm delta ceramic head were matched with 60 THAs with a 32- or 36-mm metal head based on gender, head size, follow-up, and University of California, Los Angeles activity score. Linear and volumetric wear rates were measured.

Results

At mean 6-year follow-up, the mean linear wear rates were 0.012 mm/y (standard deviation [SD] 0.045; 95% confidence interval [CI] 0.001-0.024) and 0.018 mm/y (SD 0.025; 95% CI 0.012-0.025) for the ceramic and metal groups, respectively (P = .724). The mean volumetric wear rates for the ceramic and metal head groups were 11.9 (SD 43.0; 95% CI 0.7-23.0) and 17.3 (SD 23.9; 95% CI 11.1-23.4), respectively. No significant differences were detectable in either the mean linear or volumetric wear rates (P = .380 and P = .398, respectively).

Conclusion

Second generation HXLPE had low wear rates and we were unable to detect a significant difference in wear rates with 32- or 36-mm metal and ceramic heads. We believe that this is due to the excellent tribological properties of second generation HXLPE. We continue to use ceramic as standard of care because of issues of trunnionosis with metal heads.  相似文献   
14.
PURPOSE: To evaluate the effects of sex and estrus cycle on biphasic anticonvulsant and proconvulsant modulation of seizure threshold by morphine. METHODS: The threshold for the clonic seizures (CST) induced by acute intravenous administration of gamma-aminobutyric acid (GABA)-antagonist pentylenetetrazole (PTZ) was assessed in male and female mice. Estrus cycle was assessed by vaginal smears. The effect of removing circulating sex hormones was assessed by gonadectomy. RESULTS: At baseline, diestrus females had a higher CST compared with males and estrus females. Morphine at lower doses (0.5-3 mg/kg) had a significant anticonvulsant effect in males and estrus females compared with that in vehicle-treated controls, whereas female mice in diestrus phase showed a relative subsensitivity to this effect. Morphine at higher doses (30 and 60 mg/kg) significantly decreased CST in males and diestrus females, with less relative effect in estrus mice. In both phases, morphine exerted stronger effects in males compared with females. Ovariectomy brought the baseline CST to the male level and resulted in significant expression of both phases of morphine effect but did not abolish the sex difference in responsiveness to morphine. CONCLUSIONS: The biphasic modulation of seizure threshold is subject to both constitutive sex differences in sensitivity to morphine and hormonal fluctuations during the estrus cycle.  相似文献   
15.
BACKGROUND: The optimal method for managing a patient diagnosed with atypical squamous cells of undetermined significance (ASCUS) has not yet been established. The interim guidelines published by the National Cancer Institute suggest that a patient should be referred for colposcopy after the second ASCUS diagnosis within 2 years. AIM: To assess the significance of ASCUS in predicting the presence of underlying squamous intraepithelial lesion (SIL) of the uterine cervix. STUDY POPULATION: Women undergoing colposcopy for ASCUS cytology at a teaching hospital in Tehran University, in the years 1998-2001, considered eligible to enter this retrospective study. RESULTS: Of the 266 patients who underwent colposcopy, 28 (11%) had low-grade squamous intraepithelial lesion (LSIL), 16 (6.3%) had high-grade squamous intraepithelial lesion (HSIL) two (0.8%) had squamous cell carcinoma (SCC), and 48 (18.8%) had flat condyloma. CONCLUSION: Atypical squamous cells of undetermined significance (ASCUS) on a cervical smear is a good marker for detecting underlying SIL and condyloma. Thus, immediate colposcopy and directed biopsy are appropriate follow-up procedures.  相似文献   
16.
Due to adolescents’ future crucial roles, their health needs should be included in the national health system policy. In this cross-sectional study 2010 female adolescents were recruited from randomly selected schools in Iran. To obtain their health needs, the participants completed a self-administrated questionnaire. It was revealed that emotional needs were the most important health needs of adolescents. Furthermore, there was a meaningful relationship between health needs’ score with the adolescents’ age and their mothers’ education level. Finally, the mean score of health needs was significantly higher in urban adolescents. Therefore, it is suggested that adolescents’ emotional health needs to be paid attention; otherwise irrecoverable serious problems may occur in the next generation’s health.  相似文献   
17.
Quinolone class of antibacterial agents has considerable attention to find new useful antibacterial agents. Therefore, a series of N-substituted piperazinylquinolones bearing (5-nitrofuran-2-yl)methyl moiety were synthesized and evaluated against a variety of bacteria. The methylene-bridged nitrofuran functionality has been recently used in oxazolidinone class of antibacterial agents containing piperazinyl moiety by introducing ranbezolid as a 5-nitrofuran analog of eperzolid. The results of antibacterial evaluation revealed that the influence of (5-nitrofuran-2-yl) attachment to the 7-piperazinylquinolones against different bacterial species depends on the type of substituents at the N-1 and C-8 positions. Better results were obtained with ethyl at N-1 and CF at C-8 in the term of activity against Bacillus subtilis and E. coli. While, the optimum activity against Staphylococcus aureus, Pseudomonas aeruginosa, and Klebsiella pneumonia was entailed by a molecule possessing cyclopropyl at N-1 and CH at C-8.  相似文献   
18.

Background

This study aimed to investigate the prevalence of pregnancy experience and its association with contraceptive knowledge among single adults in a low socio-economic suburban community in Kuala Lumpur, Malaysia.

Methods

A cross-sectional survey was conducted in 2012 among the Kerinchi suburban community. Of the total 3,716 individuals surveyed, young single adults between 18 and 35 years old were questioned with regard to their experience with unplanned pregnancy before marriage. Contraceptive knowledge was assessed by a series of questions on identification of method types and the affectivity of condoms for the prevention of sexually transmitted diseases.

Results

A total of 226 female and 257 male participants completed the survey. In total, eight female (3.5%) participants reported experience with an unplanned pregnancy before marriage, and five male (1.9 %) participants had the experience of impregnating their partners. The participants had a mean total score of 3.15 (SD = 1.55) for contraceptive knowledge out of a possible maximum score of five. Female participants who had experienced an unplanned pregnancy had a significantly lower contraceptive knowledge score (2.10 ± 1.48) than who had never experienced pregnancy (3.30 ± 1.35), p<0.05. Likewise, male participants who had experienced impregnating their partners had a significantly lower contraceptive knowledge score (1.60 ± 1.50) than those who did not have such experience (3.02 ± 1.59), p<0.05.

Conclusion

The results showed evidence of premarital unplanned pregnancy among this suburban community. The low level of contraceptive knowledge found in this study indicates the need for educational strategies designed to improve contraceptive knowledge.
  相似文献   
19.

Background

Health literacy and e-health literacy are important factors helping people shape awareness of health behaviours in different aspects, including sleep hygiene behaviours. Good sleep hygiene behaviours promote sleep quality and are beneficial to overall mental wellbeing.

Objective

We aimed to examine if sleep hygiene behaviours may mediate the association between health literacy/e-health literacy and mental wellbeing.

Methods

Adult Iranian subjects (n = 9775; mean [SD] age = 36.44 [11.97] years; 67.3% females) completed the Health Literacy Instrument for Adults, eHealth Literacy Scale, three items on sleep hygiene behaviour that have been used in prior research and the Short Warwick Edinburgh Mental Wellbeing Scale. Data were then subjected to structural equation modelling (SEM) including 500 bootstrapping resampling to examine whether sleep hygiene is a mediator in the relationship between health literacy/e-health literacy and mental wellbeing.

Findings

Both health literacy and e-health literacy were significantly associated with mental wellbeing (r = .63 for health literacy and .39 for e-health literacy; p < .001) and sleep hygiene behaviours (r = .58 for health literacy and .36 for e-health literacy; p < .001). Sleep hygiene behaviours were significantly associated with mental wellbeing (r = .42; p < .001). Moreover, SEM that incorporated bootstrapping approaches indicated that sleep hygiene behaviours were significant mediators in the association between health literacy/e-health literacy and mental wellbeing.

Conclusions

We conclude that health literacy and e-health literacy are associated with mental health wellbeing in the Iranian population. Additionally, the association could be mediated via sleep hygiene behaviours.

Patient or Public Contribution

The study was co-designed with healthcare providers from the vice-Chancellor's Office for Health Affairs of Qazvin University of Medical Sciences as equal partners. Moreover, the women's health volunteers were involved in the design of the study.  相似文献   
20.

Background

Colitis, a colonic inflammatory condition, showed a linkage with hepatobiliary disorders such as cirrhosis. It has been reported that both endogenous opioids and nitric oxide (NO) play critical roles in colitis pathogenesis. Moreover, opioid and NO levels showed elevation in patients with cirrhosis. The aim of this study was to evaluate the effect of cirrhosis on the experimental model of colitis and the possible involvement of opioidergic/nitrergic systems in rats.

Methods

Colitis was induced by acetic acid 28 days after bile duct ligation (BDL). L-NAME, as an inhibitor of NO synthase and naltrexone, as an antagonist of opioid receptors were administered intraperitoneally to animals during 3 days after induction of colitis. Macroscopic colitis lesion area, inflammatory mediators change, NO metabolite levels, and colon microscopic injuries were assessed 3 days after induction.

Results

Cirrhosis significantly reduced the severity of damages to the colon. Administration of L-NAME (10 mg/kg), naltrexone (10 mg/kg) and co-administration of L-NAME (1 mg/kg) and naltrexone (5 mg/kg) significantly decreased the protective effect of BDL on colitis. Nitrite elevated levels in BDL rats were significantly diminished in L-NAME- and naltrexone-treated animals. Histopathology parameters and cytokines level alterations in the colon of acetic acid-treated animals after BDL was reversed after injection of L-NAME, naltrexone, and co-administration of L-NAME (1 mg/kg) + naltrexone (5 mg/kg).

Conclusion

Cirrhosis improved the intestinal damages induced by acetic acid in rats which may be mediated through interaction of nitrergic and opioidergic systems.  相似文献   
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