[Application effect of a dual release system of androgen and its antagonist in the repair of full-thickness burn wounds in mice].

Objective: To explore the optimal ratio of dihydrotestosterone and hydroxyflutamide (hereinafter referred to as DH), construct a dual release system of androgen and its antagonist, and analyze the application effect of this system in the repair of full-thickness burn wounds in mice. Methods: This study was an experimental study. The HaCaT cells were divided into blank group (without drug culture), low baseline group, medium baseline group, and high baseline group according to the random number table (the same grouping method below), and the last three groups of cells were cultured by adding three different ratios of DH. Under a medium ratio, the mass of dihydrotestosterone in the three baseline groups from low to high was 1.4, 2.8, and 4.0 µg, respectively, and the mass of hydroxyflutamide was 1.2, 1.6, and 2.0 µg, respectively. On this basis, under a small ratio, the mass of dihydrotestosterone was reduced by half and the mass of hydroxyflutamide was increased by half; under a large ratio, the mass of dihydrotestosterone was increased by half and the mass of hydroxyflutamide was reduced by half. After culture of 2 days, the cell proliferation level was detected by cell counting kit 8 (n=4). Sixteen 6-8-week-old male BALB/c mice were used to establish a full-thickness burn wound on the back and divided into blank group, small ratio group, medium ratio group, and large ratio group, with 4 mice in each group. On post injury day (PID) 7, normal saline containing different ratios of DH was locally dropped to the wounds of mice in the last three groups of mice (the total mass of DH in the three ratio groups from small to large was 127.5, 165.0, and 202.5 µg, respectively, and the mass ratios of dihydrotestosterone to hydroxyflutamide (hereinafter referred to as drug mass ratio) were 8∶9, 8∶3, and 8∶1, respectively), afterwards, the administration was repeated every 48 hours until PID 27; normal saline was dropped to the wound of mice in blank group at the aforementioned time points. The wound healing status on PID 0 (immediately), 7, 14, 21, and 28 was observed, and the wound healing rates on PID 7, 14, 21, and 28 were calculated (n=4). On PID 28, the wound tissue was taken, which was stained with hematoxylin and eosin for observing re-epithelialization and with Masson for observing collagen fibers, and the proportion of collagen fibers was analyzed (n=3). Twenty 6-8-week-old male BALB/c mice were used to establish a full-thickness burn wound on the back and divided into ordinary scaffold group, small proportion scaffold group, medium proportion scaffold group, and large proportion scaffold group (with 5 mice in each group). On PID 7, the wound was continuously dressed with a polycaprolactone scaffold without drug and a polycaprolactone scaffold containing DH with a drug mass ratio of 1∶3, 1∶1, or 3∶1 (i.e. the dual release system of androgen and its antagonist, with total mass of DH being about 1.7 mg) prepared by using electrospinning technology until the end of the experiment. Histopathological analyses of tissue (n=3) at the same time points as those in the previous animal experiment were performed. On PID 7 and 14, the wound exudates were collected and the relative abundance of bacterial communities was analyzed using 16S ribosomal RNA high-throughput sequencing (n=3). Results: After culture of 2 days, under a small ratio, the proliferation levels of HaCaT cells in low baseline group and high baseline group were significantly higher than the level in blank group (P<0.05). As the time after injury prolonged, the wounds of all four groups of mice continued to shrink. On PID 14, the wound healing rate of mice in large ratio group was 72.5% (61.7%, 75.1%), which was close to 53.3% (49.5%, 64.4%) in blank group (P>0.05); the wound healing rates of mice in small and medium ratio groups were 74.2% (71.0%, 84.2%) and 70.4% (65.1%, 74.4%), respectively, which were significantly higher than the rate in blank group (with both Z values being -2.31, P<0.05). On PID 21, the wound healing rate of mice in small ratio group was significantly higher than that in blank group (Z=-2.31, P<0.05). On PID 28, the wounds of mice in the three ratio groups were completely re-epithelialized and the epidermis was thicker than that in blank group; compared with that in blank group, the collagen fiber content in the wound tissue of mice in the three ratio groups was higher and arranged more orderly, and the proportions of collagen fibers in the wound tissue of mice in small and large ratio groups were significantly increased (P<0.05). On PID 28, the wounds of mice in ordinary scaffold group were partially epithelialized, while the wounds of mice in the three proportion scaffold groups were almost completely epithelialized. Among them, the wounds of mice in small proportion scaffold group had the thickest epidermis. The proportion of collagen fibers in the wound tissue of mice in small proportion scaffold group was significantly increased compared with that in ordinary scaffold group (P<0.05). On PID 7, the bacterial communities with high relative abundance in the wound exudation of mice in the four groups included bacteria of Corynebacterium, Staphylococcus, and Rhodococcus. On PID 14, the bacterial communities with high relative abundance in the wound exudation of mice in the four groups included bacteria of Stenotrophomonas, Rhodococcus, and Staphylococcus, and the number of bacterial species in the wound exudation of mice in the three proportion scaffold groups was more than that in ordinary scaffold group. Conclusions: When the drug mass ratio is relatively small, DH has the effect of promoting the proliferation of HaCaT cells. The ratio of 8∶9 is the optimal mass ratio of dihydrotestosterone to hydroxyflutamide, and DH with this mass ratio can promote re-epithelialization and collagen deposition of full-thickness burn wounds in mice, and promote wound healing. The constructed dual release system of androgen and its antagonist with DH in a 1∶3 drug mass ratio contributes to the re-epithelialization and collagen deposition of the full-thickness burn wounds in mice, and can improve the diversity of wound microbiota.

Treatment outcomes for Mycobacterium avium complex: a systematic review and meta-analysis.

To evaluate the existing evidence regarding treatment regimens for Mycobacterium avium complex (MAC), a systematic review of the available therapeutic studies was conducted to assess treatment outcomes. A random-effects meta-analysis was used to assess treatment outcomes. Subgroup analyses were also conducted by separating studies based on each characteristic independently. Twenty-eight trials met the inclusion criteria. Our meta-analysis showed that the estimated pooled treatment success rate for patients with MAC disease was 39 % [95 % confidence interval (CI) 38-41 %]. The rates of failure, relapse, death, and default were 27 % (95 % CI 25-29 %), 6 % (95 % CI 5-7 %), 17 % (95 % CI 15-18 %), and 12 % (95 % CI 11-13 %), respectively. The proportion of patients treated successfully did not differ significantly on the basis of the study characteristics. However, studies with treatment regimens containing macrolides had significantly higher pooled success proportions (42 %, 95 % CI 40-44 %) than that of other studies (28 %, 95 % CI 24-32 %). Substantial heterogeneity in the study characteristics prevented more conclusive determination of what factors had the greatest effect on the proportion of patients that achieve treatment success and limited the validity of this analysis. This review underscored the importance of strong patient support and treatment follow-up systems to develop successful MAC treatment programs.

Linezolid in the treatment of MDR-TB: a retrospective clinical study.

BACKGROUND: There is limited information on Chinese patients with multidrug-resistant tuberculosis (MDR-TB) treated with a linezolid-containing regimen. OBJECTIVE: To examine treatment outcomes among MDR-TB patients who were treated with linezolid at the Shanghai Pulmonary Hospital, China. DESIGN: We retrospectively reviewed 151 patients who were treated for MDR-TB from 2007 to 2010. RESULTS: Eighteen MDR-TB patients, including 15 with extensively drug-resistant TB, received linezolid as part of their individualised treatment regimens. Patients had isolates resistant to a median of 7 drugs (range 5-11). Of the 18 cases, 17 had cavitary changes and positive sputum smear microscopy results at the time of MDR-TB diagnosis. Culture conversion occurred in all cases at a median of 7 weeks. At data censure, 9 of the 18 patients had achieved treatment success. Three continued to receive treatment. There were no deaths. Six patients had a poor outcome, including 1 default, 2 treatment failures and 3 relapses. Side effects occurred in 17 patients, including myelosuppression, neurotoxicity and gastrointestinal adverse events. Adverse events were managed by combinations of temporary suspension of linezolid in 1 patient, dose adjustment in 17 patients and symptom management in 13 patients. CONCLUSIONS: Linezolid may have efficacy in the treatment of MDR-TB, although treatment was complicated by adverse events.

Clofazimine in the treatment of multidrug-resistant tuberculosis.

Clofazimine has shown activity against Mycobacterium tuberculosis, including multidrug-resistant strains in vitro and in animal studies. However, clinical experience with clofazimine in multidrug-resistant tuberculosis (MDR-TB) is scarce. We reported our clinical experience with 39 MDR-TB patients treated with combination regimens that included clofazimine. From January 2008 to March 2011, 39 patients received clofazimine for the treatment of MDR-TB in Shanghai Pulmonary Hospital. Patients had isolates resistant to a median of six drugs (range, 2-11 drugs). Of the 39 cases, 36 had cavitary changes noted on initial chest radiograph or chest computed tomography, and positive sputum-smear microscopy results at the time of MDR-TB diagnosis. At data censure, 15 of the 39 patients had successful therapy, with at least five consistently negative cultures documented for the final 12 months of treatment. Eleven continued to receive treatment. There were no deaths. Thirteen patients had a poor outcome, including four defaults and nine treatment failures. Culture conversion occurred in 22 cases at a median of 12 weeks. Side-effects occurred in 34 patients, mainly including skin discolouration, ichthyosis and gastrointestinal adverse events. No patients reported significant toxicity likely to be attributable to clofazimine therapy. Adverse events were managed by combinations of dose adjustment and symptom management. In our experience, clofazimine was well tolerated and may have efficacy in the treatment of MDR-TB.

Diagnostic value of adenosine deaminase in cerebrospinal fluid for tuberculous meningitis: a meta-analysis.

OBJECTIVE: To determine the accuracy of adenosine deaminase (ADA) measurements in the diagnosis of tuberculous meningitis (TBM). DESIGN: After a systematic review of English language studies, the sensitivity, specificity and accuracy of ADA concentrations in the diagnosis of cerebrospinal fluid (CSF) were evaluated using random effects models. Summary receiver operating characteristic curves were used to summarise overall test performance. RESULTS: Ten studies met our inclusion criteria. The sensitivity of ADA in the diagnosis of TBM was 0.79 (95%CI 0.75-0.83), specificity 0.91 (95%CI 0.89-0.93), positive likelihood ratio 6.85 (95%CI 4.11-11.41), negative likelihood ratio 0.29 (95%CI 0.19-0.44) and diagnostic odds ratio 26.93 (95%CI 12.73-56.97). CONCLUSION: Our data suggest that ADA in the CSF can be a sensitive and specific target and a critical criteria for the diagnosis of TBM.

Skewed X-chromosome inactivation is associated with trisomy in women ascertained on the basis of recurrent spontaneous abortion or chromosomally abnormal pregnancies.

An increase in extremely skewed X-chromosome inactivation (XCI) (> or = 90%) among women who experienced recurrent spontaneous abortion (RSA) has been previously reported. To further delineate the etiology of this association, we have evaluated XCI status in 207 women who experience RSA. A significant excess of trisomic losses was observed among the women who had RSA with skewed XCI versus those without skewed XCI (P=.02). There was also a significant excess of boys among live births in this group (P=.04), which is contrary to expectations if the cause of skewed XCI was only that these women carried X-linked lethal mutations. To confirm the association between skewed XCI and the risk of trisomy, an independent group of 53 women, ascertained on the basis of a prenatal diagnosis of trisomy mosaicism, were investigated. Only cases for which the trisomy was shown to be of maternal meiotic origin were included. The results show a significantly higher level of extreme skewing (> or = 90%) in women whose pregnancies involved placental trisomy mosaicism (17%) than in either of two separate control populations (n=102 and 99) (P=.02 compared with total control subjects). An additional 11 cases were ascertained on the basis of one or more trisomic-pregnancy losses. When all women in the present study with a trisomic pregnancy (n=103) were considered together, skewed XCI was identified in 18%, as compared with 7% in all controls (n=201) (P=.005). This difference was more pronounced when a cutoff of extreme skewing of 95% was used (10% vs. 1.5% skewed; P=.002). Maternal age was not associated with skewing in either the patient or control populations and therefore cannot account for the association with trisomy. Previous studies have shown that a reduced ovarian reserve is associated with increased risk of trisomic pregnancies. We hypothesize that the association between skewed XCI and trisomic pregnancies is produced by a common mechanism that underlies both and that involves a reduction of the size of the follicular pool.

[Stability and gene expression of foreign plasmid in Bacillus subtilis BF7658].

The plasmid pAmy411 carrying thermostable alpha-amylase gene has been transduced into B. subtilis BF7658 by bacteriophage PBS1. The transduction frequency was 10(-9) transductants per PFU. The stability of plasmid pAmy411 in B. subtilis BF7658 was lower than that in B. subtilis AS1.1176, whereas the copy numbers were double than that in B. subtilis AS1.1176. The expressive level of thermostable alpha-amylase gene was about 6 times higher than that in B. subtilis AS1.1176.