[Study on the resistance of rifampicin-resistant Mycobacterium tuberculosis to anti-tuberculosis drugs in group A].

Objective: To summarize the resistance of rifampicin-resistant Mycobacterium tuberculosis to anti-tuberculosis drugs in group A. Methods: In the retrospective study, a total of 1 226 clinical isolates from suspected multidrug-resistant pulmonary tuberculosis patients in Beijing TB control system from 2016 to 2021 were identified as Mycobacterium tuberculosis (MTB) strains by MPB64 antigen detection test. Rifampicin-resistant tuberculosis (RR-TB) strains were screened by the phenotypic drug susceptibility using the proportion method. The drug susceptibilities of Levofloxacin(LFX), Moxifloxacin(MFX), Bedaquiline(BDQ) and Linezolid(LZD)were detected by the phenotypic drug susceptibility with microplate method. The drug resistance rate, drug resistance level and minimum inhibitory concentration (MIC) distribution of four anti-tuberculosis drugs in group A were analyzed. We calculated the demographic distribution of RR-TB, multidrug-resistant tuberculosis(MDR-TB), pre-extensively drug resistant tuberculosis (pre-XDR-TB), extensively drug resistant tuberculosis (XDR-TB) patients and the cross resistance of LFX and MFX, then summarized the drug-resistance spectrum of BDQ-resistant and LZD-resistant strains and the treatment outcome of RR-TB patients. Measurement data were expressed as rate or composition ratio,χ2 test was used between and within groups, and P<0.05 was considered statistically significant. Results: Among the 1 226 suspected multidrug-resistant pulmonary tuberculosis patients, the detection rates of RR/MDR/pre-XDR/XDR-TB patients were 20.8%(255/1 226), 15.2%(186/1 226), 5.7%(70/1 226), 0.5%(6/1 226), respectively. There were statistically significant differences in the distribution of patients with the four types of drug resistance in terms of age and treatment history (χ2=14.95, P=0.020;χ2=15.91, P=0.001). The drug resistance rates of LFX, MFX, BDQ and LZD in RR-TB patients were 27.5% (70/255), 27.5% (70/255), 0.4% (1/255) and 2.4% (6/255), respectively. The MICs of LFX, MFX and LZD-susceptible MTB were mainly at 0.25 mg/L, and the MIC of BDQ-susceptible MTB was mainly concentrated at 0.03 mg/L. 25.1% (64/255) of the RR MTB were resistant to both LFX and MFX, and 6 strains were resistant to LFX or MFX, showing incomplete two-way cross resistance. One BDQ-resistant strain and six LZD-resistant strains were detected. The treatment success rate of RR-TB patients was 74.4% (151/203), and there were statistically significant differences in treatment outcomes between resistant and sensitive patients on the LFX-containing treatment regimen (Fisher's exact test, P=0.012). Conclusions: The prevalence of fluoroquinolones (LFX and MFX) resistance in rifampicin-resistant MTB is very serious. LFX and MFX show incomplete bidirectional cross-resistance. BDQ and LZD have the most promising future in the treatment of MDR-TB. Improve drug-resistance testing will help to further improve the success rate of treatment.

[Preliminary study of robot-assisted ankle rehabilitation for children with cerebral palsy].

OBJECTIVE: To propose a kind of robotic ankle-foot rehabilitation system for children with cerebral palsy and to preliminarily verify its feasibility in clinical application. METHODS: A robot assisted ankle-foot rehabilitation system was specially designed and developed for children with cerebral palsy and a preliminary clinical study was conducted in Department of Rehabilitation Medicine, Peking University First Hospital. Modified Tardieu Scale and joint biomechanical properties (ankle plantar flexion resistance torque under different ankle dorsiflexion angles) were measured to analyze the muscle tone and soft tissue compliance of the ankle plantar flexors pre- and post-robotic training intervention. Six children with cerebral palsy (4 girls and 2 boys, mean age: 7 years) were recruited in this study. Each subject received 5 session robotic training and each session included 10-cycle passive stretching and static hold. SPSS 19.0 software was used for data statistical analysis. RESULTS: Both R1 and R2 angles of Modified Tardieu Scale for ankle plantar flexors after training were significantly higher than those before the treatments (Gastrocnemius: PR1=0.003, PR2=0.029; Soleus: PR1=0.002, PR2=0.034). The difference between R2 and R1 was of no statistical difference before and after the training (P=0.067 and P=0.067, respectively). After training, the ankle plantar flexion resistance torque under different dorsiflexion angles (0°, 10°, 20°, 30°) were significantly reduced than those before training (P=0.001, P=0.001, P=0.014, P=0.002, respectively). CONCLUSION: The robot assisted ankle-foot rehabilitation system can improve the contracture and soft tissue compliance of cerebral palsy children's ankle plantar flexors. All the children in the study were well tolerated and interested with the training, easy to accept and cooperate with it. This device may be suitable for application in the rehabilitation of children with cerebral palsy. However, further randomized clinical trials with larger sample size are still needed to verify the long term efficacy of this device.

[Fifth Chinese national consensus report on the management of Helicobacter pylori infection].

The fifth national consensus conference on the management of Helicobacter pylori (H.pylori) infection organized by Chinese Medical Association, Chinese Society of Gastroenterology, H. pylori and Peptic Ulcer Study Group was held at Hangzhou, Zhejiang Province on December 15-16, 2016.More than 80 members of the study group and experts in the field of H. pylori research and gastroenterology attended the meeting.Consensus preparatory group was established to draft the related statements.The quality of evidence and strength of recommendation were evaluated by GRADE system.The Delphi method using an anonymous electronic system was adopted to develop the consensus of relevant statements.Expert advices about the established statements were firstly consulted through the emails.After two rounds of consultation, the preliminary statements of consensus were discussed and modified in the conference item by item.A total of 21 core members voted for the final version, which contained a total of 48 statements and was divided into 6 parts, including indications for H. pylori eradication, diagnosis, treatment, H. pylori and gastric cancer, H. pylori infection in special populations, H. pylori and gastrointestinal microbiota.

[Distribution and drug resistance of nontuberculous Mycobacteria in Beijing].

Objective: To analyze the distribution and drug resistance of nontuberculous mycobacteria(NTM) in Beijing. Methods: Using PCR-fluorescence probe method we identified 1 552 mycobacterial isolates in 2009 and 1 553 mycobacterial isolates in 2013, which were stored by Beijing Research Institute for Tuberculosis Control.All identified NTM strains were confirmed by 16S rRNA gene sequencing, and drug sensitivity testing was performed by using 1% ratio method.SPSS 13.0 was used for statistical analysis. Results: The isolation rate for NTM in 2009 and 2013 was 3.8%(59/1 552), and 4.6%(71/1 553) respectively. A total of 130 NTM strains were identified to 13 species by 16S rRNA gene sequencing, including M. intracellulare strains 39.2%(51/130), M. kansasii strains 37.7%(49/130), M. avium strains 6.9%(9/130), M. abscessus strains 5.4%(7/130), M. fortuitum strains 3.0%(4/130), M. gordonae strains 1.5%(2/130), M. xenopi strains 1.5%(2/130), M. scrofulaceum, M. Phlei, M. smegmatis, M. vaccae, M. neoaurum, M. kumamotonense 1 strain each. For the patients infected with NTM, 87 were male and 43 were female, with an average age of 55 years. The results of drug sensitivity test from 97 strains of NTM showed that isoniazid and p-aminosalicylic acid showed the highest drug resistant rate of 98%(95/97), followed by streptomycin 94.8%(92/97), capreomycin 81.4%(79/97), amikacin 69.1%(67/97), levofloxacin 56.7%(55/97), rifampicin 54.6%(53/97), prothionamide 51.5%(50/97), and ethambutol 50.5%(49/97). Conclusions:Mycobacterium intracellulare and Mycobacterium kansasii were the main strains isolated from patients infected with NTM in Beijing. Patients infected with NTM were mostly males. NTM showed high resistance to anti-tuberculosis drugs.

The PGI-KLF4 pathway regulates self-renewal of glioma stem cells residing in the mesenchymal niches in human gliomas.

Gliomas display cellular hierarchies with self-renewing tumorigenic glioma stem cells (GSCs) at the apex. The GSC niches function as a regulator of GSC maintenance, however, the exact components of GSC niches that mediate this process are still far from fully defined. Here, we showed that glioma cells with aberrant mesenchymal phenotypes constitute a mesenchymal niche for GSCs. Using patient-derived specimens, we demonstrated that the paracrine PGI signaling, initiated by mesenchymal glioma cells, induces the self-renewal and tumorigenic potentials of GSCs through induction of KLF4. Treatment of intracranial orthotopic xenografts with shPGI or shKLF4 leads to less lethal potency. Our data therefore suggest that blockade of the PGI-KLF4 pathway may provide a therapeutic strategy against GSC niches.

Chiral recognition mechanism of acyloin-containing chiral solutes by amylose tris[(S)-α-methylbenzylcarbamate].

Although polysaccharide sorbents have been widely used for chiral separations, the recognition mechanisms have not been fully elucidated. In this study, we focus on one important commercial sorbent, amylose tris[(S)-α-methylbenzylcarbamate] (AS) sorbent. Four solutes containing acyloin, O═C-C-OH, which has a hydroxyl group in the α-position of a carbonyl group, were studied: ethyl lactate (EL), methyl mandelate (MM), benzoin (B), and pantolactone (PL). The observed retention factors (kR and kS) and enantioselectivities (α = kR/ kS) were determined in n-hexane and in hexane-isopropanol (IPA) solutions. Infrared (IR) spectroscopy and density functional theory (DFT) simulations of the interactions of these solutes with the side chains of the polymer led to a general hypothesis for the chiral recognition mechanism for these solutes: A strong H-bond forms as the primary (or "leading") nonenantioselective interaction (or "anchor" point) between the solute OH group of each enantiomer and the sorbent C═O group. A weaker H-bond forms preferably for the R enantiomer between the solute C═O groups and the sorbent NH groups. The S enantiomer is prevented from forming such a bond for steric restrictions. A third interaction might involve the O groups of the phenyl groups of the solutes. IR spectroscopy shows evidence of an intramolecular H-bond for all four solutes. The retention factors were found to increase with increasing strength of the intermolecular H-bond and with decreasing strength of the intramolecular H-bond. The enantioselectivities were found to correlate with the molecular rigidity or flexibility, as determined from the distribution of the torsion angles of the acyloin group. The enantioselectivity was higher for the more rigid molecules. Simulations of left-handed AS with 200 n-hexane molecules indicated no effect of hexane on the H-bonds in AS. Monte Carlo (MC) and molecular dynamics (MD) "docking" simulations of AS with these solutes revealed certain chiral cavities that can lead to chiral discrimination. The results support the proposed mechanism.

Seven new bifuranocoumarins, dahuribirin A-G, from Japanese Bai Zhi.

Five new spirobifuranocoumarins, dahuribirins A-E (1-5) and two new bifuranocoumarins, dahuribirins F and G (6 and 7) were isolated from Japanese Bai Zhi (the root of Angelica dahurica Benth. et Hook. var. dahurica Benth. et Hook.) and their structures were established by chemical and spectral means.

Purification of adipoyl-7-amino-3-deacetoxycephalosporanic acid from fermentation broth using stepwise elution with a synergistically adsorbed modulator.

Multicomponent adsorption data of a fermentation broth containing adipoyl-7-amino-3-deacetoxycephalosporanic acid (adipoyl-7-ADCA), a cephalosporin precursor for 7-ADCA, and two key impurities, alpha-hydroxyadipoyl-7-ADCA and alpha-aminoadipoyl-7-ADCA were obtained from batch equilibrium and frontal chromatography tests. Amberlite XAD-1600 was chosen as the resin. A rate model was applied to simulate the chromatograms. An alkaline buffer, which by itself has no affinity for the resin, was used as the eluent. The widely used reversed-phase modulator model is inaccurate in explaining the stepwise elution data. A new model, the induced competition model, has been developed to account for apparent retention of the buffer in the presence of adsorbed species. Close agreement between the simulations and the data was achieved with the new model.

[Studies on original plant of traditional Chinese drug "bai zhi" (radix Angelicae Dahuricae) and its closely related wild plants. III. Comparison of coumarins of "bai zhi" with those of closely related wild plants].

OBJECTIVE: To provide chemical data for confirming the original plant of traditional Chinese drug "Bai Zhi". METHOD: Coumarins of 4 cultivated breeds of "Bai Zhi" and 3 closely related wild plants, together with other 2 Angelica plants were compared by HPLC. RESULT: According to coumarin patterns, 4 cultivated breeds of "Bai Zhi" and 3 closely related wild plants could be divided into 3 groups: 1. 4 cultivated breeds of "Bai Zhi" ("Chuan Bai Zhi", "Hang Bai Zhi", "Qi Bai Zhi" and "Yu Bai Zhi") and Angelica dahurica var. formosana; 2. A. dahurica; 3. A. porphyrocaulis. CONCLUSION: In point of the coumarin components, A. dahurica var. formosana is closer to traditional Chinese drug "Bai Zhi" than the others.

[Studies on original plant of traditional Chinese drug "bai zhi" (radix Angelicae Dahuricae) and its closely related wild plants. IV. Discussion on original plant and cultivation history of traditional Chinese drug "bai zhi" and evolution of its closely related wild plants].

OBJECTIVE: To confirm the original plant of traditional Chinese drug "Bai Zhi" and to inquire into the cultivation history of "Bai Zhi" and evolution of closely related wild plants of "Bai Zhi". METHOD: Various research results obtained were synthesized and discussed according to historical and current data. RESULT: Obtained research results, historical and current data showed almost no difference. CONCLUSION: 1. Angelica dahurica var. formosana must be the original plant of traditional Chinese drug "Bai Zhi". 2. A. porphyrocaulis should be treated as a variety of A. dahurica, named as A. dahurica var. porphyrocaulis. 3. 4 sorts of Chinese traditional drug "Bai Zhi" (Chuang Bai Zhi, Hang Bai Zhi, Qi Bai Zhi and Yu Bai Zhi) should not be taxonomically distinguished. The history of utilization and cultivation of "Bai Zhi", and the evolutional relation of the closely related wild plants of "Bai Zhi" (A. dahurica, A. dahurica var. formosana, and A. dahurica var. porphyrocaulis) were also discussed.

[Studies on original plant of traditional Chinese drug "bai zhi" (radix Angelicae Dahuricae) and its closely related wild plants. I. Morphological and anatomical studies on "bai zhi" and closely related wild plants].

OBJECTIVE: To supplement morphological and anatomical data for confirming the original plant of traditional Chinese drug "Bai Zhi" (Radix Angelicae Dahuricae). METHOD: Morphologocal observation and anatomical study were made on 4 cultivated breeds and closely related wild plants of "Bai Zhi". RESULT: According to morphological and anatomical characteristics discovered in this paper, 7 samples noted above could be divided into 3 groups: 1. 4 breeds ("Chuan Bai Zhi", "Hang Bai Zhi", "Qi Bai Zhi" and "Yu Bai Zhi") and Angelica dahurica var. formosana; 2. A. dahurica; 3. A. porphyrocaulis. CONCLUSION: In the morphological and anatomical point of view, A. dahurica var. formosana is closer to traditional Chinese drug "Bai Zhi" than others.

[Studies on original plant of traditional Chinese drug "bai zhi" (radix Angelicae Dahuricae) and its closely related wild plants. II. Karyological and pollen morphological studies on "bai zhi" and closely related wild plants].

OBJECTIVE: To supplement cytobiological and pollen morphological data for confirming the original plant of traditional Chinese drug "Bai Zhi". METHOD: Karyological study and pollen observation were made on "Bai Zhi" and its closely related wild plants. RESULT: Similarities and differences of "Bai Zhi" and its closely related wild plants were found. CONCLUSION: 1. 4 cultivated breeds of "Bai Zhi", Angelica dahurica, A. dahurica var. formosana, A. porphyrocaulis are really closely related plants. 2. A. dahurica var. formosana is closer to traditional Chinese drug "Bai Zhi" than others.

Optimization of throughput and desorbent consumption in simulated moving-bed chromatography for paclitaxel purification.

In simulated moving-bed (SMB) applications, throughput and desorbent consumption are two key factors that control process cost. For a given adsorbent volume and product purity requirements, throughput and desorbent consumption depend on desorbent composition, column configuration, column length to diameter ratio, and adsorbent particle size. In this study, these design parameters are systematically examined for paclitaxel purification. The results show that if adsorbent particle size, column dimensions and column configuration are fixed, the higher the product purity required, the lower the throughput. If product purity and yield are fixed, the larger the solute migration speed ratio, the higher the throughput, and the lower the desorbent consumption. If total bed volume and product purities are fixed, the longer the separation zones, the higher the throughput, but the higher the desorbent flow-rate. An intermediate configuration gives the minimum desorbent consumption. If there are no limits on pressure drop or zone flow-rate, the larger the column length to diameter ratio, the smaller the adsorbent particle size, the higher the throughput, and the lower the desorbent consumption. If the maximum zone flow-rate is controlled by the pressure drop limit and not by the standing waves requirement, the longer the columns, the lower the zone flow-rates and the lower the throughput. For 150 microns adsorbent particles and a maximum zone flow-rate of 300 ml/min, a design with optimal throughput and desorbent consumption is found for paclitaxel purification.

Ten-year results for Brånemark implants immediately loaded with fixed prostheses at implant placement.

This investigation was initiated to develop a method to provide patients with a fixed provisional prosthesis placed at the time of implant placement. Sixty-three standard 3.75-mm Nobel Biocare implants of varying lengths were placed into mandibular sites in 10 patients and followed for up to 10 years. Twenty-eight implants were immediately loaded at implant placement, providing support for fixed provisional prostheses, while 35 adjacent implants were allowed to heal submerged and stress-free. Following a 3-month healing period, the submerged implants were exposed and definitive reconstruction was accomplished. All 10 prostheses supported by 28 implants placed into immediate function at the time of implant placement were successful during the 3-month healing period. Of these 28 implants placed into immediate function, 4 ultimately failed. Of the 35 submerged implants, all are osseointegrated and in function to date. Life-table analysis demonstrates an overall 10-year survival rate of 93.4% for all implants. The 10-year life-table analysis of survival is 84.7% for immediately loaded implants and 100% for submerged implants. Statistical analysis of the submerged versus immediately loaded implants demonstrates failure rates for immediately loaded implants to be significantly higher (P = .022 by the log rank test). These data demonstrate that although mandibular implants can be successfully placed into immediate function in the short term to support fixed provisional prostheses, long-term prognosis is guarded for those implants placed into immediate function distal to the incisor region.

Allogeneic bone marrow transplantation for Gaucher disease--a case report.

A Chinese patient who presented painful disability of right hip was diagnosed as having type 1 Gaucher disease four years later when hepatosplenomegaly was found. Splenectomy was performed but her condition did not improve. So human leukocyte antigen (HLA)-matched sibling allogeneic bone marrow transplantation (BMT) was performed. The transplantation course was smooth. Although her bone marrow was in mixed chimeric state, symptoms disappeared and her growth caught up with normal level after BMT. Gaucher disease should be considered in cases with hepatosplenomegaly and bone disorder of unknown causes. Allogeneic BMT is an effective treatment, but the treatment-related risk should be seriously evaluated and the late complications should be closely monitored.

Acute monteggia fractures in children.

BACKGROUND: Monteggia fracture rarely occurs in children. If it occurs, type I fracture is most commonly seen. We study the functional results of nonsurgical management in acute cases. METHODS: From July, 1988 through October, 1994, we encountered 15 cases of acute Monteggia fractures, accounting for 2.3% of forearm fractures. Twelve were males and three were females, at an average age of 7 years and 10 months. Nine fractures occurred on left non-dominant side, six occurred on right dominant side. There were eleven type I (73.3%), no type II, three type III (20%), and one type IV (6.7%) fractures. All of these patients received closed reduction with long arm casting, and the most stable position of fracture was supination of the forearm and flexion of the elbow. RESULTS: After follow-up for an average of 45.9 months, all fractures were found to unite without residual deformity of ulna or dislocation of the radial head. The functional results were excellent. Posterior interosseous nerve palsy occurred in one patient before treatment, and recovered spontaneously. CONCLUSIONS: Unlike adults, children with Monteggia fractures can get excellent results from closed reduction with long arm casting.

Anterior tibia spine fracture in children: follow-up evaluation by biomechanical studies.

BACKGROUND: The treatment of anterior tibial spine (ATS) fracture in children is in controversy. Previous studies have shown that most of the children who sustained ATS fractures have objective evidence of the anterior cruciate ligament (ACL) laxity at follow-up, but detailed biomechanical analysis of the knee joint has seldom been performed. METHODS: Eight ATS fractures in children at a mean age of 12 years were treated from 1989 to 1994. Two were of Meyer's classification type I, 3 were of type II, and 3 were of type III. The treatment varied from casting to open reduction & internal fixation (ORIF) by pulling through suture or biofix absorbable screw. Patients were followed with radiological, clinical and biomechanical analysis. KT 1000 knee arthrometer was used to evaluate the laxity of ACL. Cybex isokinetic machine was used to evaluate knee extensor and flexor strength. RESULTS: During an average follow-up period of 47 months, all fractures showed to unite well on X-ray except 1 untreated type I fracture who had malunion. Only one had subjective complaint of instability, but 3 had clinical signs of instability. Objective evidence of laxity, determined by KT-1000 arthrometer, was noted in 4 patients. Decreased muscle strength, determined by Cybex isokinetic machine, was more prominent in hamstrings than in quadriceps. CONCLUSIONS: Patients with milder ATS fracture (type I & II), if treated inappropriately, may still result in ACL laxity and knee muscle strength deficiency. Type III ATS fractures, if treated well by ORIF, tend to recover nearly normal ACL function and muscle strength.

Chinese achondroplasia is also defined by recurrent G380R mutations of the fibroblast growth factor receptor-3 gene.

Achondroplasia is the most common form of dwarfism in humans. A recurrent glycine-to-arginine mutation at codon 380 (G380R) of the transmembrane domain of fibroblast growth factor receptor-3 (FGFR-3) was identified in the majority of Western and Japanese patients, which is uncommon in other autosomal dominant genetic diseases. To determine whether this mutation is also common in Chinese patients, we examined the G380R mutation in Chinese patients with achondroplasia. Of ten patients studied, including eight sporadic cases and one family with two affected members, all have the same G380R mutation with a G-to-A transition. Our results support the argument that the G380R mutation of FGFR-3 is the most frequent mutation causing achondroplasia across different populations.

Plasma protein adsorption to highly permeable hemodialysis membranes.

Although membrane adsorption of plasma proteins is one of several factors determining the biocompatibility and mass transfer characteristics of a hemodialyzer, this process has not been evaluated rigorously. We performed an equilibrium and kinetic analysis of the binding of proteins of differing molecular weight to highly permeable membranes of differing hydrophobicity and surface change. Hydrophobic, anionic polyacrylonitrile (PAN) and hydrophilic, uncharged cellulose triacetate (CT) membrane fragments were incubated in buffer containing radioiodinated beta 2-microglobulin (beta 2m) or bovine serum albumin (BSA). From an initial solution concentration of 50 mg/liter, both membranes adsorbed significantly more beta 2m than BSA at equilibrium (PAN, 352 +/- 30 vs. 32.1 +/- 2.4 ng; CT, 87.0 +/- 0.6 vs. 30.8 +/- 1.7 ng). These results were consistent with membrane pore exclusion of BSA. Comparison of the slopes of the equilibrium isotherm lines (concentration range, 0 to 220 mg/liter) showed the PAN binding affinity for beta 2m and BSA was 28 and 1.4 times that of CT, respectively. In kinetic studies, the approach to equilibrium versus (time)1/2 was assessed. For all protein-membrane combinations, this relationship was linear, consistent with a diffusion-controlled process. This latter characteristic permitted the determination of beta 2m membrane diffusivity values for both PAN and CT, which were found to be 0.30 and 3.25 x 10(-7) cm2/sec, respectively. These data suggest membrane hydrophobicity more significantly influences the binding of low-molecular weight proteins than that of pore-excluded proteins. In addition, these results demonstrate electrostatic membrane-protein interactions may influence the kinetics of both the adsorption and transmembrane mass transfer of plasma proteins.