[Improved unilateral puncture PVP based on 3D printing technology for the treatment of osteoporotic vertebral compression fracture].

OBJECTIVE: To investigate the clinical effect of unilateral percutaneous vertebroplasty (PVP) combined with 3D printing technology for the treatment of thoracolumbar osteoporotic compression fracture. METHODS: A total of 77 patients with thoracolumbar osteoporotic compression fractures from October 2020 to April 2022 were included in the study, all of which were vertebral body compression fractures caused by trauma. According to different treatment methods, they were divided into experimental group and control group. Thirty-two patients used 3D printing technology to improve unilateral transpedicle puncture vertebroplasty in the experimental group, there were 5 males and 27 females, aged from 63 to 91 years old with an average of (77.59±8.75) years old. Forty-five patients were treated with traditional bilateral pedicle puncture vertebroplasty, including 7 males and 38 females, aged from 60 to 88 years old with an average of(74.89±7.37) years old. Operation time, intraoperative C-arm X-ray times, anesthetic dosage, bone cement injection amount, bone cement diffusion good and good rate, complications, vertebral height, kyphotic angle (Cobb angle), visual analogue scale(VAS), Oswestry disability index (ODI) and other indicators were recorded before and after surgery, and statistically analyzed. RESULTS: All patients were followed up for 6 to 23 months, with preoperative imaging studies, confirmed for thoracolumbar osteoporosis compression fractures, two groups of patients with postoperative complications, no special two groups of patients' age, gender, body mass index (BMI), time were injured, the injured vertebral distribution had no statistical difference(P>0.05), comparable data. Two groups of patients with bone cement injection, bone cement dispersion rate, preoperative and postoperative vertebral body height, protruding after spine angle(Cobb angle), VAS, ODI had no statistical difference(P>0.05). The operative time, intraoperative fluoroscopy times and anesthetic dosage were statistically different between the two groups(P<0.05). Compared with the traditional bilateral puncture group, the modified unilateral puncture group combined with 3D printing technology had shorter operation time, fewer intraoperative fluoroscopy times and less anesthetic dosage. The height of anterior vertebral edge, kyphosis angle (Cobb angle), VAS score and ODI of the affected vertebrae were statistically different between two groups at each time point after surgery(P<0.05). CONCLUSION: In the treatment of thoracolumbar osteoporotic compression fractures, 3D printing technology is used to improve unilateral puncture PVP, which is convenient and simple, less trauma, short operation time, fewer fluoroscopy times, satisfactory distribution of bone cement, vertebral height recovery and kyphotic Angle correction, and good functional improvement.

[Effects of aerobic exercise and resveratrol on the expressions of JAK2 and TGF-ß1 in renal tissue of type 2 diabetes rats].

Objective: To investigate the effects of aerobic exercise and resveratrol on janus kinase 2(JAK2) and transforming growth factor-ß1(TGF-ß1) in renal tissue of type 2 diabetes rats and its mechanism. Methods: The model of type 2 diabetic rats was established through SD rats fed high-fat diet for 5 weeks together with intraperitoneal infecting after a low dose of STZ. The rats were randomly divided into diabetic control group(DC), diabetic exercise group(DE), diabetic resveratrol group(DR), diabetic exercise and resveratrol group(DER), normal control group(NC), 12 rats in each group. Exercise-related groups performed 8 weeks treadmill exercise (20 m/min, 60 min/day). Resveratrol was administered to drug-related groups for 8 weeks (45 mg/kg, 7 day/week). Eight weeks later, we examined blood glucose concentrations, 24 h microalbuminuria(UA), serum creatinine(Scr), blood urea nitrogen(BUN), and the expressions of TGF-ß1, janus kinase 2(JAK2) and JAK2 mRNA in renal tissue. Results: After eight weeks of intervention, compared with NC group, the concentrations blood glucose, 24 h UA, Scr, BUN, the expressions of TGF-ß1, JAK2 and JAK2 mRNA were increased significantly in DC group(P＜0.05). Compared with DC group, the concentrations of blood glucose, 24 h UA, Scr, BUN, the expressions of TGF-ß1, JAK2 and JAK2 mRNA were decreased significantly in DE group, DR group and DER group(P＜0.05). Conclusion: Exercise, resveratrol and combined intervention may decrease the expressions of JAK2 mRNA, JAK2 and TGF-ß1, which further attenuate renal injury for type 2 diabetes. The renal protective effect produced by exercise and resveratrol combined intervention is better than that produced by exercise or resveratrol intervention alone.

[Experimental study of individualized 3D printing-guided template combined with thoracolumbar pedicle screw placement for the treatment of ankylosing spondylitis].

OBJECTIVE: To evaluate accuracy and safety of individualized 3D printing guided template for thoracolumbar pedicle screw placement in patients with ankylosing spondylitis. METHODS: From January 2016 to September 2019, thoracolumbar spine three-dimensional CT data of 8 patients with ankylosing spondylitis were included, Mimics 17.0 and ideaMaker computer software were applied to design thoracolumbar pedicle screw guided template of patients with AS, physical model of all patients (T10-L2)were printed by 3D printer, 2 parts in each patient, and divided into guide-plate-assisted screw group (experimental group) and free-hand nail group (control group). Thoracolumbar pedicle screws of both groups were placed by the same spinal surgeon. The accuracy of pedicle screw placement between two groups were evaluated according to results of postoperative CT, the accuracy of the fixation of thoracolumbar pedicle screw was divided into 4 grades, grade 0 and 1 screws were acceptable nails, grade 2 and 3 screws were unacceptable nails. The diameter and length of pedicle screws, the distance between entry point and posterior median line designed by preoperative 3D printing were compared with actual use in operation. RESULTS: Twenty three blocks of thoracolumbar 3D printing screw of ankylosing spondylitis guided templates were designed and printed in guide-plate-assisted screw group, 46 screws were inserted and 44 screws were accepted. The time of implanting a screw into thoracolumbar pedicle was (4.20±1.15) min, the frequency of X-ray was (5.00±1.25) times and the average adjustment times of screw and Kirschner needle during screw placement was (1.76±1.32) times. In the control group, 46 nails were placed by traditional surgical method and 30 screws were accepted. The time of implanting a screw into thoracolumbar pedicle was (14.67±2.23) min, the frequency of X-ray fluoroscopy was (14.46±2.21) times and the average times of Kirschner needle adjustment was (4.76±3.39) times. The success rates between experimental group and control group were 95.65%(44 / 46) and 56.22%(30 / 46) respectively, and had statistical difference (χ2=13.538, P<0.05). There was no significant difference in diameter, length of pedicle screws and the distance of posterior median line between virtual designed by 3D printing before operation and actual situation in opertaion (P>0.05). The operation time of inserting a single screw, the times of X-ray fluoroscopy, and the average times of adjustment screw and Kirschner needle in experimental group were significant less than those in control group(P<0.01). CONCLUSION: The personalized guide template assisted the thoracolumbar fixation designed by 3D printing could significantly improve safety, accuracy and efficiency of surgery, especially suitable for thoracolumbar vertebral bodies requiring posterior pedicle screw fixation for fracture or dislocation with AS.

Treatment quality and outcome for multidrug-resistant tuberculosis patients in four regions of China: a cohort study.

BACKGROUND: China incurs an extremely low treatment coverage of multidrug-resistant tuberculosis (MDR-TB). This study aimed to understand the experience of MDR-TB patients on quality of health care, and the clinical impact through an up to six-year follow-up. METHODS: Cohorts of MDR-TB patients were built in TB/MDR-TB designated hospitals in four regions of China from 2014 to 2015. Patients were followed up during treatment course, and yearly confirmation afterward until 2019. Delay in MDR-TB diagnosis and treatment was calculated upon bacteriological confirmation and treatment initiation. Risk factors for unfavourable outcomes were identified by multivariate logistic regression. RESULTS: Among 1168 bacteriological-positive TB patients identified from a 12-million population, 58 (5.0%) MDR-TB cases were detected. The median delay for MDR-TB diagnosis was 90.0 days, with 13.8% having a delay above 180.0 days. MDR-TB treatment was only recommended to 19 (32.8%) participants, while the rest continued with regimen for drug-susceptible TB. In MDR-TB treatment group, 36.8% achieved treatment success, while the others had incomplete treatment (21.1%), loss to follow-up (36.8%) and TB relapse (5.3%). For non-MDR-TB treatment group, 33.3% succeeded, 25.6% relapsed, 2.6% failed, 23.1% died, and 15.4% were lost to follow-up. Overall, only 35.7% (20/56) of detected MDR-TB patients had favourable outcomes and higher education level was positively associated with it (adjusted odds ratio [aOR]: 3.60, 95% confidence interval [CI]: 1.04-12.5). CONCLUSIONS: A large proportion of patients did not receive MDR-TB treatment and had unfavourable outcomes. Delayed MDR-TB diagnosis resulted in poor quality of MDR-TB care. Rapid diagnosis, regulated patient management and high-quality MDR-TB treatment should be enhanced in China.

[3D printing technology assisted the preoperative planning and application value in adult kyphoscoliosis deformity].

OBJECTIVE: To explore the application value of 3D printing technology in preoperative surgery plan and intraoperative auxiliary operation for adult kyphoscoliosis deformity. METHODS: The clinical data of 12 adult patients with kyphoscoliosis deformity treated from September 2017 to January 2019 were retrospectively analyzed. There were 3 males and 9 females, aged from 21 to 63 years old with an average of (47.67±13.32) years old. Among them, 4 cases were congenital kyphoscoliosis, 2 cases were old tuberculosis thoracolumbar kyphosis ; 2 cases were idiopathic kyphoscoliosis, 4 cases were degenerative kyphoscoliosis. The CT scan data of the patient's spine was imported into Mimics17.0 software to establish the three dimensional model of the spine, and the spine model was produced by 3D printer. Using the spine model simulated operation, preoperative surgery program planning and formulated a precise surgery, and further analysed postoperative imaging parameters improvement. All the patients were followed up for more than 1 year. Before and after operation and at the last follow-up, the scoliosis Cobb angle, maximum kyphosis Cobb angle, and coronal plane balance (distance between C 7 plumbline and center sacral vertical line, C7PL-CSVL), sagittal plane balance (sagittal vertical axis, SVA), pelvic parameters and other related imaging parameters were measured to further evaluate its orthopedic effect. RESULTS: Twelve patients with spine deformity were treated with different osteotomy and internal fixation fusion methods under the guidance of a 1∶1 spine model (pedicle screw placement of 4 patients with severe deformity were assisted by pedicle screw guide plates), nail placement and osteotomy have good effects, no major tissue damage such as blood vessels, nerves and spinal cord during and after surgery, no complications such as cerebrospinal fluid leakage and infection. Preoperative Cobb angle of scoliosis was (56.5±22.5) °, Cobb angle of kyphosis was (65.2±19.5) °, C7 PL-CSVL was (45.8±16.9) mm, SVA was (48.7±25.4) mm. Postoperative at 4 weeks, Cobb angle of scoliosis was (20.8±11.5) °, and Cobb angle of kyphosis was (22.0±6.6) °, with correction rates of (65.1±9.7)% and (64.6± 10.6)%, respectively ; C7 PL-CSVL was (22.3±8.9) mm, and SVA was (23.3±13.1) mm, all of which were significantly improved compared with preoperative results. The mean follow-up time was (18.5±7.9) months in 12 patients. At the last follow-up, the Cobb angles of scoliosis and kyphosis were (22.2±10.8) ° and (23.6±7.7) °, respectively, C7 PL-CSVL was (23.5±10.8) mm, and SVA was (24.7±12.5) mm. The results were statistically significant compared preoperative (P<0.05). There was no significant difference at the postoperative at 4 weeks and the last follow-up (P>0.05). CONCLUSION: The 3D print model can visually and clearly show the vertebral morphology and structure of adult kyphoscolisis and its spatial relationship with the adjacent vertebrae, blood vessels, and nerves, which provides a good and intuitive stereoscopic anatomical structure observation for the individualization of the surgical plan. Pre-simulation of operations to determine the internal fixation, fusion segment and osteotomy orthopedic way, may to provide a reference for actual clinical surgery, and can improve the accuracy and safety of surgery.

Organic degradation and extracellular products of pure oxygen aerated activated sludge under different F/M conditions.

This study aimed to investigate the effect of food to microorganisms rate (F/M) on organic removal, extracellular polymeric substances (EPS) and soluble microbial products (SMP) of the pure oxygen aerated activated sludge running in batch mode. The F/M rates were controlled by adjusting the MLSS concentrations (2000, 5000, 8000 mg/L) and/or the initial TOC concentrations (100, 500 mg/L). Results showed that at high F/M rate (0.25 kg TOC/kg MLSS), the substrate degradation rate in the oxygen aerated reactor could reach 1.347 mg TOC/(L·min)), much higher than that in the air aerated reactor (0.640 mg TOC/(L·min)). The SMP concentrations with oxygen aeration were also higher than those with air aeration under high F/M conditions. The total EPS contents in the pure oxygen aerated sludge were significantly lower regardless of the different F/M rates. High F/M condition would lead to more amount of polysaccharides synthesis rather than proteins synthesis in EPS.

Three GPI-anchored alkaline phosphatases are involved in the intoxication of Cry1Ca toxin to Spodoptera exigua larvae.

Glycosylphosphatidylinositol (GPI)-anchored alkaline phosphatase (ALP) isoforms are crucial for the intoxication of crystal proteins (Cry) to several insect species. We cloned five SeALPs from the larval midgut of Spodoptera exigua, a major pest of many crops. All five SeALPs contain a signal peptide at the N-terminus, a phosphatase domain, and a GPI-anchor site at the C-terminus. Additionally, the sequences encode two or three potential N-glycosylation sites. The five SeALPs were highly expressed at the larval stage, especially in the larval gut or Malpighian tubules. Ingestion over four consecutive days of double-stranded RNAs (dsRNAs) targeting SeALP1, SeALP2, SeALP3, SeALP4, and SeALP5 significantly reduced the corresponding mRNA levels by 60.0%, 40.0%, 65.6%, 48.1%, and 69.1% respectively, compared with the levels in control larvae that fed on non-specific dsRNA (dsEGFP). When larvae that previously ingested phosphate buffered saline (PBS)-, dsEGFP-, or five dsSeALPs-overlaid diets were then exposed to a diet containing Cry1Ca, the larval mortalities after six days were 70.0%, 71.8%, 49.1%, 54.9%, 65.3%, 52.5%, and 77.4%, respectively. ANOVA analysis revealed that the larvae that previously fed on the dsSeALP1-, dsSeALP2-, and dsSeALP4-overlaid diets had significantly lower mortalities than those that previously ingested the PBS-, dsEGFP-, dsSeALP3- and dsSeALP5-overlaid diets. The results suggest that SeALP1, SeALP2 and SeALP4 are involved in the intoxication of Cry1Ca to S. exigua larvae.

Dynamic changes of bacterial community in activated sludge with pressurized aeration in a sequencing batch reactor.

This study aimed to investigate the organic removal efficiency and microbial population dynamics in activated sludge with pressurized aeration. The activated sludge was fed with synthetic wastewater composed of simple carbon source to avoid the effect of complex components on microbial communities. The pressurized acclimation process was conducted in a bench-scale sequencing batch reactor (SBR) under 0.3 MPa gage pressure. Another SBR was running in atmospheric environment as a control reactor, with the same operation parameters except for the pressure. Bacterial diversity was investigated by Illumina sequencing technology. The results showed that the total organic carbon removal efficiency of the pressurized reactor was significantly higher, while the mixed liquor suspended solids concentrations were much lower than those of the control reactor. Moderate pressure of 0.3 MPa had little effect on Alpha-diversity of bacterial communities due to the similar running conditions, e.g., feed water, solids retention time (SRT) and the cyclic change of dissolved oxygen (DO) concentrations. Although the relative percentage of the bacterial community changed among samples, there was no major change of predominant bacterial populations between the pressurized group and the control group. Pressurized aeration would have a far-reaching impact on microbial community in activated sludge when treating wastewaters being unfavorable to the dissolution of oxygen.

The Spodoptera exigua (Lepidoptera: Noctuidae) ABCC2 Mediates Cry1Ac Cytotoxicity and, in Conjunction with Cadherin, Contributes to Enhance Cry1Ca Toxicity in Sf9 Cells.

In insects, the mode of Cry1A toxins action has been studied in detail and many receptors that participate in the process are known. Recent evidence has revealed that an ABC transporter (ABCC2) is involved in conferring resistance to Cry1A toxins and that ABCC2 could be a receptor of Cry1A. However, it is not known whether Cry1Ca interacts with the same receptor proteins as Cry1A. In this study, we report the cloning of an ABC transporter gene, SeABCC2b, from the midgut of Spodoptera exigua (Hübner) larvae, and its expression in Sf9 cells for a functional analysis. The addition of Cry1Ca and Cry1Ac to Sf9 cell culture caused swelling in 28.5% and 93.9% of the SeABCC2-expressing cells, respectively. In contrast, only 7.4% and 1.3% of the controls cells swelled in the presence of Cry1Ca and Cry1Ac. Thus, SeABCC2b-expressing Sf9 cells had increased susceptibility to Cry1Ca and Cry1Ac. Similarly, S. exigua cadherin (SeCad1b) expressed in Sf9 cells caused 47.1% and 1.8% of the SeCad1b-expressing cells to swell to Cry1Ca and Cry1Ac exposure. Therefore, Sf9 cells expressing SeCad1b were more sensitive to Cry1Ca than Cry1Ac. Together, our data suggest that SeABCC2b from S. exigua mediates Cry1Ac cytotoxicity and, in conjunction with SeCad1b, contributes to enhance Cry1Ca toxicity in Sf9 cells.

[The cluster and drug-resistant characteristics of Beijing genotype Mycobacterium tuberculosis in eastern rural China].

OBJECTIVE: To investigate the distribution of Mycobacterium tuberculosis (MTB) Beijing genotype, which was isolated from tuberculosis (TB) patients registered in local TB dispensaries in Deqing and Guanyun county respectively within 1 year, as well as its drug-resistant phenotypic and genotypic profiles and genotyping features. METHODS: A total of 399 TB patients were enrolled from 2 counties. Of the 351 TB patients with MTB isolates available, 237 were male, and 114 were female; aged from 18 - 82 (46 ± 35) years. The proportion method and DNA sequencing were used to define the susceptibility of the isolates to 4 first line anti-TB drugs and the related mutation. Beijing genotype MTB strains were identified by Spoligotyping, while the "cluster" strains and the "unique" strains were defined by IS6110 restriction fragment length polymorphism (RFLP). RESULTS: Beijing genotype MTB strains were identified in 243 of the 351 strains isolated, and the proportion of multi-drug resistance, mono-resistance to rifampin and isoniazid among Beijing genotype MTB was 18.5% (45/243), 43.2% (105/243) and 22.2% (54/243) respectively, all being significantly higher than the non-Beijing genotype MTB, 7.4% (8/108), 24.1% (26/108) and 12.0% (13/108) respectively. katG and rpoB mutations were observed more common among Beijing genotype MTB than among non-Beijing genotype MTB, 13.2% (32/243) and 4.6% (5/108) respectively, OR = 2.553, 95%CI: 1.031 - 6.324. The Beijing genotype MTB was more likely to be clustered than non-Beijing genotype MTB, 41.2% (100/243) and 11.1% (12/108) respectively, OR = 5.503, 95%CI: 2.851 - 10.622. CONCLUSIONS: In eastern rural China, TB patients infected with the Beijing genotype MTB may have a higher risk to develop isoniazid-or rifampin-resistance and multi-drug resistance. The disease is more likely due to recent transmission.

[Molecular-epidemiological study on the transmission of drug resistant tuberculosis and its influencing factors in rural areas of eastern China].

OBJECTIVE: To investigate the contribution of recent transmission in the epidemic of drug-resistant Mycobacterium tuberculosis (M.TB) and related factors from biomedical and social-demographic perspectives in the Eastern rural areas of China. METHODS: Identified by proportion method of drug susceptibility test, 223 drug resistant M.TB isolates and their hosts were included in the present study. These drug resistant tuberculosis isolates were first genotyped by Mycobacterial Interspersed Repetitive Units (MIRU), and those isolates with identical MIRU genotype were further classified by IS6110 restricted fragment polymorphism (RFLP). 'Cluster' was defined as two patients' M. TB isolates harboring the identical MIRU genotype and IS6110-based RFLP pattern simultaneously. Unique strains denoted those with the unparalleled MIRU genotype in the study collection. Socio-demographic and biomedical characteristics of host patients were compared between the clusters and unique groups through univariate and multivariate logistic regression analysis. RESULTS: Based on the MIRU-IS6110 pattern, there were 52 isolates belonged to the "cluster" group and 171 as the "unique" group. Drug resistant M.TB strain isolated from patients at the age of 30 - 60 year had a higher probability of being clustered, comparing to those from patients below 30 years of age (30.9% vs. 11.9%; OR = 3.297; 95%CI: 1.169 - 9.297). Such finding were also seen in the isolates from patients with previous treatment history compared to newly diagnosed patients (32.9% vs. 18.4%; OR = 2.163, 95%CI: 1.144 - 4.090). The multi-drug resistant M.TB strain was found to have been more frequently clustered when comparing to the mono-drug resistant M.TB (47.2% vs. 15.5%; OR = 4.773; 95%CI: 2.316 - 9.837). The transmission pattern of drug resistant tuberculosis was presented mainly by the sporadic distribution in small group within rural villages. CONCLUSION: Transmission of drug-resistant tuberculosis was seen in the population living in the Eastern rural areas of China, and causal contact within villages was considered as the main route of recent transmission. Patients at middle age and having previous tuberculosis treatment history might have increased the risk of transmission by patients with drug resistant tuberculosis.

[The combined application of multiple genotyping methods in identifying genotypes of Mycobacterium tuberculosis strain circulating in rural China].

OBJECTIVE: To evaluate the performance of MIRUs (mycobacterial interspersed repetitive units) genotyping alone, IS6110-RFLP (IS6110 restriction fragment length polymorphism) genotyping alone and their combination applied in the molecular epidemiological study of Mycobacterium tuberculosis (MTB) isolates circulating in rural China. METHODS: A cross-sectional study was designed to collect MTB isolates from the TB patients registered in local TB dispensaries of Deqing county and Guanyun county from 2004 to 2005. The proportion method was used to determine drug susceptibility of MTB isolates to the first line anti-TB drugs (isoniazid, rifampin, ethambutol and streptomycin). The Beijing family of MTB was identified by Spoligotyping. All isolates were genotyped by MIRUs alone, IS6110-RFLP alone and their combination. RESULTS: Of the 351 studied MTB isolates, 243 (69.2%) had the genotypes that belonged to the Beijing family, and 223 (63.5%) were resistant to at least 1 anti-TB drug, including 53 (15.1%) resistant to isoniazid and rifampin simultaneously or multidrug resistant (MDR). The heterogeneity of 12 MIRUs loci differed from 0.76 in MIRU26 to 0.003 in MIRU2. MIRUs alone identified 235 genotypes (HGI = 0.9317), including 46 "clusters" containing 162 isolates and 189 "unique" pattern/isolates. Thirty-eight isolates comprised the largest MIRUs defined cluster and presented MIRUs type 2233 2517 3533. MIRUs based clusters were further identified by IS6110-RFLP into 28 subgroups containing 80 isolates (HGI = 0.9989). In comparison, IS6110-RFLP determined 267 genotypes from all isolates, including 46 "clusters" containing 130 isolates (HGI = 0.9684) and 221 "unique" pattern/isolates. All the 46 IS6110-RFLP defined clusters could also be further identified by MIRUs into 31 subgroups (HGI = 0.9992). The performance of MIRUs prior to IS6110-RFLP combination was comparable to that of IS6110-RFLP prior to MIRUs combination, especially in Beijing genotype strain (HGI: 0.9930 vs 0.9933) and MDR-TB strains (HGI: 0.9965 vs 0.9963). CONCLUSION: For feasibility, cost and discriminatory power, MIRUs prior to IS6110-RFLP combination is more suitable for the massive epidemiological investigation of MTB in rural China.

[Population-based molecular epidemiologic study of rifampicin-resistant tuberculosis in rural area of eastern China].

OBJECTIVE: To describe the drug resistance-related molecular characterization and clustering feature of rifampicin-resistant (RIFr) M.tuberculosis (M.tb) in rural area of eastern China. METHODS: All patients diagnosed as RIFr M.tb in Deqing and Guanyun county during one year period from 2004 to 2005 were included in the study. By proportion method of drug susceptibility test, 65 isolates were identified resistant to rifampicin and regarded as the studied strains. Hotspots of rpoB gene and katG gene were detected by direct DNA sequencing. Beijing genotype M.tb strains were identified by spoligotyping. IS6110-RFLP (IS6110 restriction fragment length polymorphism) and clustering analysis were performed on all RIFr M.tb isolates available. RESULTS: The mutations in 81 bp rifampicin-resistance determination region (RRDR) of the rpoB gene were observed among 60 (92%) RIFr M.tb isolates, with mutation in locus 531 observed in the majority of RIFr isolates (37/65). 49 (82%) of the 60 isolates were multidrug resistant TB (MDR-TB), which were referred to as resistant to both RIF and isoniazid (INH). Through spoligotyping, 54(83%) isolates were identified as Beijing genotype strains. In clustering analysis of IS6110-RFLP, 24 isolates were grouped into 11 clusters, suggesting that the recent transmission of M.tb did exist among patients. Regarding the drug resistance profile in clusters, all the isolates in clusters were also MDR-TB. 7 clusters contained isolates carrying different mutations were related to RIF-resistance. Multivariate analysis showed the proportion of new cases in clustered patients is higher than that in the un-clustered patients (new/previously treated: OR = 3.342; 95%CI: 1.081 - 10.32). CONCLUSION: The acquisition of rifampicin resistance in M.tb was more likely to be resulted from the selective growth of RIFr M.tb in the specific drug resistant M.tb such as isoniazid-resistant M.tb. Previous elongated irregular treatment might favor the epidemic of RIFr M.tb.

[A-cohort study on the standard short-course chemotherapy program for drug resistant tuberculosis in the rural counties in Eastern China].

OBJECTIVE: To investigate the therapeutic efficacy of short course chemotherapy (SCC) on drug resistant tuberculosis (DR-TB) cases and related influencing socioeconomic factors. TB patients registered in local county TB dispensaries of two rural counties were followed up in Deqing and Guanyun of Eastern China, during 2004/2005. METHODS: Culture-positive patients (Deqing: 182, Guanyun: 217) were selected as subjects of this study. A cohort of TB patients was established at the beginning of their treatment and each patient was followed-up three times by questionnaires. Proportional method of drug susceptibility test was used to define the resistance to the 1st-line anti-TB drugs. chi2 test Kaplan-Meier method and Cox analysis were applied in multivariate analysis to investigate the negative conversion of smear positive sputum, treatment result of SCC and its socioeconomic influencing factors. RESULTS: The cure rates of multi-drug resistant TB (MDR-TB), other drug resistant TB (ODR-TB) and pan-drug susceptible TB, were 58.3%, 91.0%, 98.7% and 51.3%, 89.5%, 93.5% respectively in Deqing and Guanyun. The liver dysfunction (RR = 0.18, 95% CI: 0.04-0.69) and previous treatment history (RR = 0.26, 95% CI: 0.07-0.93) were associated with treatment result among MDR-TB. Result on treatment in ODR-TB was influenced by previous treatment history (RR = 0.66, 95% CI: 0.44-0.98) and Patient delay (> 2 weeks) (RR = 0.67, 95% CI: 0.46- 0.97). CONCLUSION: The priority in treating MDR-TB would include: managing side effect, developing the fast sensitive drug susceptibility test and modifying the treatment regimen corresponding to drug resistance.

[Analysis of simple sequence repeats in genomes of Sclerotinia sclerotiorum and Botrytis cinerea].

Simple sequence repeats or microsatellites have been used as genetic markers in population genetics because of their abundance and length variation between different individuals. This study examined the SSRs in the completely sequenced Sclerotinia sclerotiorum and Botrytis cinerea genomes. The occurrences, relative abundance, relative density, most common motifs, and the longest SSRs in the two species were analyzed, and compared with other plant pathogenic fungal species, such as Fusarium graminearum, Magnaporthe grisea and Ustilago maydis. The results demonstrated that the SSRs are abundant in S. sclerotiorum and B. cinerea genomes, and 6 539 and 8 627 SSRs were obtained from these species. The types and distributions of SSRs have similarities between the two species. In the genomes of S. sclerotiorum and B. cinerea, tetra-, penta- and hexa-nucleotide repeats were more abundant than other species, indicating high mutation rates in these species. Furthermore, the abundance and relative density of SSRs were not influenced by the genome sizes and GC content. The analysis in this study provided useful information on applications of microsatellites in population genetics of S. sclerotiorum and B. cinerea.

Serious response during tilt-table test in elderly and its prophylactic management.

OBJECTIVE: To evaluate the serious response during tilt-table test (TTT) and its prophylactic management. METHOD: Seventy-six elderly patients were tested at a tilt angle of 70 degrees for a maximum of 45 min and then subjected to isoproterenol-provocative tilt testing. ECG and blood pressure were monitored during the test and patients were kept at normal saline condition through a peripheral intravenous duct. RESULTS: Fifty-one of 76 patients were defined as positive including 23 having serious response; 6 of the 23 patients had arteriosclerosis involving internal carotid arteries and 7 cases had bradycardia, two of which were associated with II degrees -I A-V block and the others with chronic atrial fibrillation. The serious response consisted of cardiac arrest for more than 5 s (6 cases), or serious bradycardia for more than 1 min (7 cases) or serious hypotension for more than 1 min (10 cases). Those with serious response were managed by returning to supine position, thus driving up legs and intravenous atropine, CPR (2 cases with cardiac arrest) and needing oxygen supplementation (11 cases). Only 2 hypotension patients recovered gradually by 10 min after emergency management, while others recovered rapidly with no complications. CONCLUSION: Although non-invasive, TTT may result in serious response, especially in elderly. Therefore proper patient selection, control of isoproterenol infusion and close observation of vital signs are decisive for a safe consequence.

[Study on the epidemiology and determinants of drug-resistant tuberculosis in northern rural area of Jiangsu province].

OBJECTIVE: To understand the determinants and epidemiology of drug-resistant tuberculosis (TB) in rural area. METHODS: All the diagnosed TB patients in a county with directly observed treatment (DOTS) short-course program in 2002 and a sample of patients in another county without DOTS program located in northern Jiangsu province were surveyed with questionnaires. Drug susceptibility testing (DST) for positive cultures were performed by standardized proportion method. Univariable analysis and multivariate nonconditional logistic regression modeling were applied for data analysis. RESULTS: Among the 152 patients with DST results, 32.9% of the cases showed resistance to at least one of the first-line anti-tuberculosis drugs with 26.3% to isoniazid, 18.4% to rifampin and 17.1% to both isoniazid and rifampin respectively. Previous treatments for TB and residence in the county without DOTS program were independent risk factors for isoniazid and rifampin resistance. TB patients showing indifferent to their health and delayed health seeking for more than 1 month were more likely to have rifampin resistance. Independent predictors of multidrug-resistant TB would include delayed health seeking for more than 1 month (OR = 4.66, 95% CI: 1.26 - 17.24), residing in the county without a DOTS program (OR = 3.01, 95% CI: 1.10 - 8.22), indifference to their health condition (OR = 5.13, 95% CI: 1.06 - 24.90) and suffering from chronic diseases (OR = 0.22, 95% CI: 0.05 - 0.87). CONCLUSION: Drug-resistant TB was quite serious in this rural areas, mainly associated with man-made factors but partly due to the availability of the transmission.