Objective: To analyze the expression of sigma factor in drug resistance gene mutations of Mycobacterium tuberculosis (MTB), so as to provide a reference for the drug resistance mechanism of tuberculosis. Methods: Clinical sputum specimens of outpatients at Tianjin Center for Tuberculosis from 2018 to 2022 were collected. A total of 899 MTB-positive strains were obtained by culture, and 492 phenotypically sensitive strains and 407 phenotypically resistant strains were identified by an in vitro phenotypic drug susceptibility test. Thirty drug-sensitive strains of MTB were randomly selected, and 98 drug-resistant strains with specific resistance phenotypes were chosen; all were subjected to melting curve analysis for detection of drug-resistance gene mutations. The strains were divided into sensitive strains without gene mutation, isoniazid-resistant strains with inhA mutation or katG mutation, rifampicin-resistant strains with rpoB mutation, and multigene mutation-resistant strains with inhA+rpoB mutation or katG+rpoB mutation. The mRNA relative expression of sigma factor was detected by fluorescence quantitative PCR, and the ratio of sigma factor mRNA relative expression between the experimental strain and the standard strain >2 was used to screen for highly expressed sigma factor. The differences in sigma factor mRNA relative expression and high expression rate between drug-resistant gene mutant strains and sensitive strains were analyzed. Results: Thirty sensitive strains and 90 drug-resistant strains were included. Among them, there were 16 strains with inhA mutation, 22 strains with katG mutation, 13 strains with rpoB mutation, 15 strains with inhA+rpoB mutation, and 24 strains with katG+rpoB mutation. Compared to the sigma factors of the sensitive strains, the mRNA expression levels of sigG and sigI in inhA-mutated strains, sigF, sigG, sigH, sigI, sigJ, and sigL in katG-mutated strains, and sigF, sigG, sigH, sigJ, and sigL in rpoB-mutated, inhA+rpoB-mutated, and katG+rpoB-mutated strains were significantly higher (all P<0.05). Additionally, the high-expression rates of sigI in inhA-mutated strains, sigF, sigG, sigI, sigJ, and sigL in katG-mutated and inhA+rpoB-mutated strains, and sigF, sigG, sigH, sigJ, and sigL in rpoB-mutated and katG+rpoB-mutated strains were also higher (all P<0.05). Conclusion Compared to sensitive MTB strains, sigI showed higher relative expression of mRNA and high-expression rate in inhA-mutated strains, and sigF, sigG, sigJ, and sigL had higher mRNA relative expression and high-expression rates in katG-mutated, rpoB-mutated, and multi-drug-resistant strains.

This study aims to elucidate the successful extubation process of a premature infant encountering difficulties due to an intracavicular knot at the proximal part of peripherally inserted central catheter (PICC). The reason for the difficulty in removing the catheter was determined by X-ray to be the knot at the proximal end of the PICC through the periphery. With the cooperation of a nurse specializing in static therapy and an interventional physician, the catheter was successfully removed based on the improved modified Sedinger technique .

This study aims to elucidate the successful extubation process of a premature infant encountering difficulties due to an intracavicular knot at the proximal part of peripherally inserted central catheter (PICC). The reason for the difficulty in removing the catheter was determined by X-ray to be the knot at the proximal end of the PICC through the periphery. With the cooperation of a nurse specializing in static therapy and an interventional physician, the catheter was successfully removed based on the improved modified Sedinger technique .

Objective:To optimize the alcohol precipitation process of Quhan Zhufeng Granules.Methods:Taking the volume fraction of ethanol, the relative density of the concentrated solution and the standing time as the investigation factors, the Z value of the total evaluation of gentiopicrin content, oleanolic acid content and dry paste yield of gentiana macrophylla as the evaluation indexes, the star-point design-response surface method was used to optimize the alcohol precipitation process.Results:The optimal the alcohol precipitation process of Quhan Zhufeng Granules: concentration relative density 1.08 g/ml (90-95 ℃), alcohol precipitation at the end of volume fraction of 62% ethanol, standing for 16 h.Conclusion:The alcohol precipitation process using overall desirability and central composite design is stable and feasible, and has good predictability, which can provide experimental basis for further scale production.

BACKGROUND:Intervertebral disc degeneration is an important cause of low back pain.At present,there are many modeling methods for disc degeneration in China and abroad,but there is not a model for low back pain due to disc degeneration. OBJECTIVE:To compare the effect of mechanical puncture combined with tumor necrosis factor α and complete Freund's adjuvant with a conventional disc mechanical puncture alone. METHODS:A total of 18 male adult Sprague-Dawley rats were randomly divided into 3 groups,with 6 animals in each group.No treatment was given in the blank group.Animal models of intervertebral disc degeneration were made in the L4-5 segments of rats in the control using conventional mechanical puncture.In the experimental group,on the basis of mechanical puncture,tumor necrosis factor α+complete Freund's adjuvant was injected into the L4-5 intervertebral discs using a microinjector to establish a model of disc degeneration induced by mechanical puncture combined with inflammatory factors.Four weeks after surgery,the pain threshold of rats was measured by the hot plate method for assessing the perception of heat injury in rats with intervertebral disc degeneration.MRI examination was performed to observe the disc degeneration in each group.ELISA was used to detect the levels of serum tumor necrosis factor α,interleukin 1β,interleukin 6 and prostaglandin E2.Hematoxylin-eosin and Safranin O-fast green staining were used to observe the morphological changes of the disc. RESULTS AND CONCLUSION:In terms of pain,the behavioral pain threshold of the experimental group was continuously decreased,and the levels of serum inflammatory factors were significantly higher compared with the control group.In terms of morphology,the MRI results showed that the L4-5 nucleus pulposus signal completely disappeared in the experimental group.Histopathological results showed that in the control group,the nucleus pulposus was intact,more notochord cells were visible,and some fiber rings were ruptured,while in the experimental group,there are fewer notochord cells and the structure of the nucleus pulposus and fibrous ring is disturbed,with the boundary disappearing.To conclude,mechanical puncture combined with tumor necrosis factor alpha and complete Freund's adjuvant can successfully establish a discogenic low back pain model in rats.This operation is simple and economical to achieve obvious disc degeneration and low back pain,with greatly shortened molding cycle.This model can be used as a reference for studying discogenic low back pain models.

Objective To investigate the role of theophylline drugs in acute exacerbation stage of chron-ic obstructive pulmonary disease (AECOPD).Methods The clinical data of 401 patients with AECOPD ad-mitted and treated in this hospital from January 2016 to September 2022 were retrospectively analyzed.The patients were divided into the drug group (n=308) and control group (n=93) according to whether or not u-sing theophylline drugs.The control group was given the conventional treatment,and the drug group was giv-en theophylline drugs on the basis of conventional treatment.The hospitalization duration,C-reactive protein (CRP),procalcitonin (PCT),blood routine[WBC,neutrophil,hemoglobin,hematocrit (HCT),platelet-lym-phocyte ratio (PLR),neutrophil to lymphocyte ratio (NLR),eosinophils,basophil]changes were compared between the two groups,and the parameters with differences conducted the subgroup analysis to observe the effect of different types of theophylline.Results Before treatment,there was no statistically significant differ-ence in the baseline data between the drug group and the control group,and the number of basophils between the aminophylline group and doxophylline group (P>0.05).After treatment,there was no statistically signif-icant difference in PCT,CRP,WBC,neutrophil,hemoglobin,HCT,PLR,NLR and eosinophil between the drug group and control group (P>0.05).The length of hospital stay in the drug group was shorter than that of the control group,and the basophils count was less than that of the control group,and the difference was statisti-cally significant (P<0.05).After treatment,there was no statistically significant difference in the hospitaliza-tion duration in the aminophylline group and doxophylline group in the drug group subgroups (P>0.05),but the basophils count was higher than that of the doxofylline group (P<0.05).Conclusion Theophylline drugs could significantly shorten the hospitalization duration and reduce the basophils in the patients with AECO-PD.There is no significant difference in shortening the hospitalization duration between aminophylline and doxophylline,but aminophylline's effect on basophils is significantly stronger than that of doxophylline.

Objective To analyze the diagnosis status of negative etiological pulmonary tuberculosis test re-sults in Wuhan,and to provide scientific basis for improving the diagnosis strategy of etiological negative pul-monary tuberculosis.Methods From January 1 to February 28,2019,a total of 241 patients with negative eti-ological tuberculosis who were registered,reported and treated in 1 municipal and 2 district-level designated hospitals were selected.The medical record data,chest imaging examination and laboratory examination re-sults of the selected patients were reviewed and extracted,and the quality of etiological examination and ima-ging examination of patients with negative etiological pulmonary tuberculosis were analyzed.Results Among the 241 patients,88.8％(214/241)of the patients met the diagnostic criteria for negative etiological pulmona-ry tuberculosis,and 96.3％(232/241)of the patients had chest imaging examinations that were consistent with the original diagnostic results.Patients received sputum smear examination,sputum culture,and molecu-lar biology test accounted for 97.9％(236/241),73.9％(178/241)and 65.6％(158/241),respectively.Patients received anti-tuberculosis antibody test,tuberculin skin test,y-interferon release and diagnostic anti-infection treatment accounted for 54.8％(132/241),46.5％(112/241),26.1％(63/241),and 53.1％(128/241),respec-tively.The sputum culture detection rate of urban area was higher than those of central and remote urban are-as,the rate of central urban area was higher than that of remote urban areas,and the molecular biology detec-tion rate of urban area was higher than those of central and remote urban area,with statistical significance(P＜0.001).The detection rate of anti-tuberculosis antibody of urban area was lower than that of central ur-ban area,and the differences were statistically significant(P＜0.001).The rate of diagnostic anti-infective therapy of central urban area was higher than that of urban area and the remote urban area,and the rate in ur-ban area was higher than that of remote urban area,and the differences were statistically significant(P＜0.001).Conclusion It is necessary to further standardize the diagnosis of negative etiological pulmonany tu-berculosis of designated tuberculosis hospitals.The proportion of diagnostic anti-infection treatment and auxil-iary examination at the municipal level needs to be increased,and the frequency and items of laboratory etio-logical examination at the district level need to be increased.

Objective　To investigate whether the expression regulation of regulatory gene Sigma factors (sigA-sigM) is related to isoniazid resistance phenotype in isoniazid-resistant Mycobacterium tuberculosis (MTB) caused by katG mutations, and to provide reference for the study of the molecular mechanism of isoniazid resistance. Methods　A total of 90 strains were collected from the patients undergoing first-line treatment at the Tianjin Tuberculosis Control Center during drug resistance testing from 2020 to 2022, of which 30 strains were sensitive strains without katG mutation, and 65 strains were isoniazid-resistant strains caused by katG mutation, including 11 strains resistant only to isoniazid, 24 strains resistant to both isoniazid and streptomycin, and 30 strains multidrug-resistant to isoniazid, streptomycin, and rifampicin. After the strains were collected on the isoniazid drug-containing medium, the RNA of the strains was extracted, and the relative expression levels of Sigma factors were detected by reverse transcription-polymerase chain reaction(RT-PCR). The expression differences of Sigma factors in different isoniazid drug-resistant phenotypes were analyzed by the Mann-Whitney U test. Results The gene expression levels of sigA, sigC, sigF, sigG, sigH, sigI, sigJ, sigK, sigL in isoniazid mono-resistant group were significantly higher than those in pan-isoniazid-sensitive group (Z=4.368, 5.701, 6.865, 4.021, 5.126, 2.670, 5.983, 4.701, 5.490, P all<0.001). The gene expression levels of sigA, sigC, sigF, sigG, sigH, sigI, sigJ, sigK, sigL in poly-resistance group were significantly higher than those in pan-sensitivity group (Z=-5.017, -4.670, -4.667, -5.456, -4.083, -5.393, -4.712, -6.971, -8.206, -5.211, P all<0.001). In multidrug-resistant (MDR) group, the gene expression levels of sigC, sigD, sigE, sigF, sigG, sigH, sigI, sigJ, sigK, sigL were significantly higher than those in pan-isoniazid-sensitive group (Z=-5.537, -4.003, -5.216, -7.328, -7.730, -5.658, -4.440, -6.036, -4.862, -4.312, P all<0.001). The expression levels of sigB, sigF, sigG showed statistically significant differences in gene expression between the isoniazid mono-resistant, isoniazid poly-resistant, and isoniazid multidrug-resistant groups (Z=10.139, 7.735, 14.532, P all<0.001). The expression rates of sigF, sigG, sigI, sigJ, and sigL in the isoniazid-resistant group were significantly higher than those in isoniazid sensitive group (χ2=17.410. 45.673. 57.661. 42.896. 26.363, P all<0.001). Conclusions sigF, sigG, sigI, sigJ, and sigL are associated with isoniazid resistance due to katG mutations.

Radiotherapy is widely used in the management of advanced colorectal cancer (CRC). However, the clinical efficacy is limited by the safe irradiated dose. Sensitizing tumor cells to radiotherapy via interrupting DNA repair is a promising approach to conquering the limitation. The BRCA1-BARD1 complex has been demonstrated to play a critical role in homologous recombination (HR) DSB repair, and its functions may be affected by HERC2 or BAP1. Accumulated evidence illustrates that the ubiquitination-deubiquitination balance is involved in these processes; however, the precise mechanism for the cross-talk among these proteins in HR repair following radiation hasn't been defined. Through activity-based profiling, we identified PT33 as an active entity for HR repair suppression. Subsequently, we revealed that BAP1 serves as a novel molecular target of PT33 via a CRISPR-based deubiquitinase screen. Mechanistically, pharmacological covalent inhibition of BAP1 with PT33 recruits HERC2 to compete with BARD1 for BRCA1 interaction, interrupting HR repair. Consequently, PT33 treatment can substantially enhance the sensitivity of CRC cells to radiotherapy in vitro and in vivo. Overall, these findings provide a mechanistic basis for PT33-induced HR suppression and may guide an effective strategy to improve therapeutic gain.

OBJECTIVE: To investigate the effect of inhibition of RAB27 protein family, which plays a pivotal role in exosome secretion, on biological behaviors of triple-negative breast cancer cells. METHODS: Quantitative real-time PCR and Western blotting were used to examine the expressions of RAB27 family and exosome secretion in 3 triple-negative breast cancer cell lines (MDA-MB-231, MDA-MB-468, and Hs578T) and a normal breast epithelial cell line (MCF10A). The effect of small interfering RNA (siRNA)-mediated silencing of RAB27a and RAB27b on exosome secretion in the 3 breast cancer cell lines was detected using Western blotting, and the changes in cell proliferation, invasion and adhesion were evaluated. RESULTS: Compared with normal breast epithelial cells, the 3 triple-negative breast cancer cell lines exhibited more active exosome secretion (P < 0.001) and showed significantly higher expressions of RAB27a and RAB27b at both the mRNA and protein levels (P < 0.01). Silencing of RAB27a in the breast cancer cells significantly down-regulated exosome secretion (P < 0.001), while silencing of RAB27b did not significantly affect exosome secretion. The 3 breast cancer cell lines with RAB27a silencing-induced down-regulation of exosome secretion showed obvious inhibition of proliferation, invasion and adhesion (P < 0.01) as compared with the cell lines with RAB27b silencing. CONCLUSION RAB27a plays central role in the exosome secretion in triple-negative breast cancer cells, and inhibiting RAB27a can inhibit the proliferation, invasion and adhesion of the cells.
Humans ; rab GTP-Binding Proteins/metabolism* ; Triple Negative Breast Neoplasms ; Cell Line, Tumor ; rab27 GTP-Binding Proteins/metabolism* ; RNA, Small Interfering/genetics* ; Cell Proliferation/genetics* ; Gene Expression Regulation, Neoplastic