Species identification and antimicrobial susceptibility testing of non-tuberculous mycobacteria isolated in Chongqing, Southwest China.

With the rapid rise in the prevalence of non-tuberculous mycobacteria (NTM) diseases across the world, the microbiological diagnosis of NTM isolates is becoming increasingly important for the diagnosis and treatment of NTM disease. In this study, the clinical presentation, species distribution and drug susceptibility of patients with NTM disease visiting the Chongqing Public Health Medical Centre during March 2016-April 2019 were retrospectively analysed. Among the 146 patients with NTM disease, eight NTM species (complex) were identified. The predominant NTM species in these patients were identified to be Mycobacterium abscessus complex (53, 36.3%), M. intracellulare (38, 26%) and M. fortuitum (17, 11.7%). In addition, two or more species were isolated from 7.5% of the patients. Pulmonary NTM disease (142, 97.3%) showed the highest prevalence among the patients. It was observed that 40.1% of the patients with pulmonary NTM disease had chronic pulmonary obstructive disease and bronchiectasis, while 22.5% had prior tuberculosis. Male patients showed more association with the conditions of cough and haemoptysis than the female patients. In an in vitro antimicrobial susceptibility testing, most of the species showed susceptibility to linezolid, amikacin and clarithromycin, while M. fortuitum exhibited low susceptibility to tobramycin. In conclusion, the prevalence of NTM disease, especially that of the pulmonary NTM disease, is common in Southwest China. Species identification and drug susceptibility testing are thus extremely important to ensure appropriate treatment regimens for patient care and management.

Environmental taxes, technological innovation and firm performance: Evidence from China's manufacturing firms.

Based on panel data from 2011 to 2019 for heavily polluting listed firms in the manufacturing industry, this paper examines the impact of environmental taxes on technological innovation and firm performance using the propensity score matching (PSM) and differences-in-differences (DID) methods. The empirical results show the following: (i) Firm performance and innovation quantity are positively affected by environmental taxes. The average effects of environmental taxes on firm performance and innovation quantity are 1.28 and 0.219, respectively. However, environmental taxes have no significant impact on innovation quality. (ii) A mechanism analysis reveals that innovation quantity plays a significant partial mediating role in the positive effect of environmental taxes on firm performance. (iii) Heterogeneity analysis shows that different environmental tax rates lead to a variation in innovation quantity and firm performance across regions. The positive effect of environmental taxes on innovation quantity is only confirmed in high-tax and low-tax areas. Meanwhile, high environmental taxes are related to better firm performance. Based on the research, policy recommendations are put forward to optimise environmental taxes, such as improving the environmental tax system and coordinating environmental tax and innovation policies.

Prevalence and analysis of acquired and transmitted integrase strand transfer inhibitor-associated HIV-1 drug resistance in Chongqing, China.

In this study, we examined the occurrence of acquired and transmitted drug resistance to integrase strand transfer inhibitor (INSTI) in HIV-1 strains in Chongqing (China) for guiding for the routine testing of INSTI-associated HIV-1 genotype resistance. Plasma samples were obtained from HIV-1 patients at Chongqing Public Health Medical Center from July 2019 to August 2022. Besides, amplification, sequence, and analysis of the portion of the HIV-1 pol gene that encodes the integrase protein were implemented to identify INSTI resistance. Integrase sequence data was harvested for a comprehensive cohort of 1032 patients infected with HIV-1. This cohort consisted of 564 ART-naive patients, 465 ART-treated patients, and 3 patients with an unknown treatment history. Within the study group, we identified INSTI resistance in 21 patients (2.03%, 21/1032), including 17 ART-treated patients (3.66%, 17/465). Among the ART-treated patients, 12 were INSTI-treated (11.76%, 12/102), 5 were INSTI-naive (1.38%, 5/363), and 4 were ART-ineffective patients (0.71%, 4/564). The prevalent major resistance mutation was Q148R (0.48%, 5/1032), while the most prevalent accessory resistance mutation was E157Q (1.65%, 17/1032). In light of the above, it is recommended that the incidence of accessory genotype analysis should be considered before starting any future INSTI-based therapy, especially in patients with drug resistance to NRTIs and NNRTIs and the reduction of INSTI sensitivity should be carefully monitored and investigated. Regular monitoring for resistance should be implemented after the use of INSTIs, and, importantly, ongoing monitoring of the decreasing susceptibility to INSTIs is crucial following the initiation of treatment with INSTIs.

Patterns and trends of primary drug-resistant tuberculosis in Chongqing, China, from 2012 to 2020.

Primary drug-resistant tuberculosis (DR-TB) contributes significantly to the global TB epidemic, particularly in countries with high TB burdens. This study aimed to investigate the characteristics of primary DR-TB prevalence in Chongqing, China, from 2012 to 2020. A total of 4546 newly diagnosed and 2769 relapse TB patients admitted to the hospital from 2012 to 2020 were included. Categorical variables were compared using Pearson chi-square test or Fisher exact test, as appropriate. Logistic regression analysis was performed to determine factors associated with primary DR-TB. The rate of primary DR-TB was 24.5%, whereas that of acquired DR-TB was 67.8%. Among newly diagnosed TB cases, the percentage of DR-TB (from 48.9 to 44.2%), mono-resistant TB (from 11.8 to 9.7%), multidrug-resistant TB (MDR-TB; from 25.3 to 6.9%), and pre-extensive drug-resistant TB (from 13.7 to 5.8%) showed a decreasing trend from 2012 to 2020. Age from 15 to 64 years was a risk factor for the development of primary DR-TB (15-44 years: adjusted odds ratio = 2.227, 95% confidence interval: 1.053-4.710; 45-64 years: adjusted odds ratio = 2.223, 95% confidence interval: 1.048-4.717). The rates of primary DR-TB (P = .041) and MDR-TB (P = .007) were significantly higher in the age group of 15 to 64 years than in the age groups of ≤14 years and ≥65 years. Noticeably, rising trends of primary DR-TB (from 0 to 27.3%) and MDR-TB (from 0 to 9.1%) in the population of ≤14 years were observed from 2012 to 2020. Although the rate of primary DR-TB showed a downward trend, a rising drug-resistance rate among some particular subgroups was still observed. Further control of primary DR-TB should focus more on TB patients aged 15 to 64 years.

Evaluation of Xpert MTB/RIF assay for the diagnosis of extrapulmonary tuberculosis in Southwest China.

The purpose of this study was to determine the diagnostic efficacy of Xpert MTB/RIF assay for rapid diagnosis of Tuberculosis (TB) and detection of rifampicin (RIF) resistance in patients suspected of having EPTB, assessing it against traditional culture and drug susceptibility test (DST) by proportional method, and the ability to predict multidrug resistance TB by Xpert MTB/RIF assay. In this study, the Xpert MTB/RIF assay was applied to 1,614 extrapulmonary specimens. Compared with TB culture and Composite Reference Standard (CRS), the Xpert MTB/RIF assay had a high sensitivity and specificity for detection of EPTB. Depending on the culture method or CRS as the standard, sensitivity of the Xpert MTB/RIF assay for detection of MTB in pleural effusion, cerebrospinal fluid, thoracic drainage fluid and throat swabs specimens were lower than that of other specimens. According to the experimental results, we have reason to believe that Xpert MTB/RIF assay is a rapid and simple technique with high sensitivity and specificity for diagnosing EPTB and detecting drug resistance in variety of specimens. Xpert MTB/RIF assay combined with DST maybe identify more cases of multi-drug resistant tuberculosis (MDR-TB).

Characteristics and Trend of Drug-Resistant Tuberculosis at a Major Specialized Hospital in Chongqing, China: 2016 Versus 2019.

OBJECTIVE: The epidemic of drug-resistant tuberculosis (DR-TB) has become a major concern in global TB control. This study aimed to investigate the patterns and trend of DR-TB epidemic between different time periods in Chongqing. METHODS: A total of 985 and 835 culture positive TB patients with drug susceptibility testing (DST) results admitted to the hospital in 2016 and 2019, respectively, were included. Chi-square testing was used to compare the prevalence and trends of DR-TB in 2016 and 2019. RESULTS: The proportion of previously treated TB cases with culture positivity was 45.7% in 2019, significantly higher than that in 2016 (39.1%, P = 0.004). The overall rate of drug resistance in 2019 was 43.1%, higher than that in 2016 (40.2%). The rates of multi-drug resistant TB (MDR-TB) and pre-extensively drug resistant TB (pre-XDR-TB) increased significantly from 2016 to 2019 among all TB cases (MDR: 25% vs 33.4%, P < 0.001 and pre-XDR: 7.1% vs 12.8%, P < 0.001, respectively) and previously treated TB cases (MDR: 46.5% vs 56%, P = 0.008 and pre-XDR: 13.2% vs 21.5%, P = 0.003, respectively). CONCLUSIONS: Our findings indicated that the prevalence of DR-TB remains high in Chongqing. The trend of resistance to anti-TB drugs beccame worse between 2016 and 2019. Moreover, acquired MDR may play a major role in MDR-TB epidemic in Chongqing. Therefore, rapid diagnosis and effective treatment of TB patients will be important to reduce the burden of DR-TB in Chongqing.

Chirality transcription in the anion-coordination-driven assembly of tetrahedral cages.

Enantiopure A4L4 tetrahedral cages (either ΔΔΔΔ or ΛΛΛΛ) were obtained through the anion-coordination-driven assembly (ACDA) of phosphate anions with C3-symmetric tris-bis(urea) ligands bearing chiral groups.

Establishment of a highly efficient conjugation protocol for Streptomyces kanamyceticus ATCC12853.

Kanamycin B as the secondary metabolite of wild-type Streptomyces kanamyceticus (S. kanamyceticus) ATCC12853 is often used for the synthesis of dibekacin and arbekacin. To construct the strain has the ability for kanamycin B production; the pSET152 derivatives from Escherichia coli ET12567 were introduced to S. kanamyceticus by intergeneric conjugal transfer. In this study, we established a reliable genetic manipulation system for S. kanamyceticus. The key factors of conjugal transfer were evaluated, including donor-to-recipient ratio, heat-shock, and the overlaying time of antibiotics. When spores were used as recipient, the optimal conjugation frequency was up to 6.7 × 10-6 . And mycelia were used as an alternative recipient for conjugation instead of spores; the most suitable donor-to-recipient ratio is 1:1 (107 :107 ). After incubated for only 10-12 hr and overlaid with antibiotics subsequently, the conjugation frequency can reach to 6.2 × 10-5 which is sufficient for gene knockout and other genetic operation. Based on the optimized conjugal transfer condition, kanJ was knocked out successfully. The kanamycin B yield of kanJ-disruption strain can reach to 543.18 ± 42 mg/L while the kanamycin B yield of wild-type strain was only 46.57 ± 12 mg/L. The current work helps improve the content of kanamycin B in the fermentation broth of S. kanamyceticus effectively to ensure the supply for the synthesis of several critical semisynthetic antibiotics.

Selective recognition of choline phosphate by tripodal hexa-urea receptors with dual binding sites: crystal and solution evidence.

Two tripodal hexa-urea receptors functionalized with aromatic terminal groups are capable of binding choline phosphate (CP). Crystal structures of the host-guest complexes reveal that the zwitterion CP is efficiently encapsulated in the tripodal hosts in a dual-site binding mode. The phosphate tail of CP is coordinated by the urea groups and the quaternary ammonium head is bound in a 'composite aromatic box' through cation-π and hydrogen-bonding interactions. Such a partial aromatic binding environment for the Me3N-+ cation mimics that of most enzymes catalyzing the conversion of quaternary ammonium substrates. Moreover, NMR, ESI-MS, and fluorescence studies demonstrate the selective binding and sensing of CP over other competing species such as ADP, ATP, choline and derivatives.

Molecular characterization of para-aminosalicylic acid resistant Mycobacterium tuberculosis clinical isolates in southwestern China.

PURPOSE: The aim of this study is to investigate para-aminosalicylic acid (PAS) resistance-related gene mutations in clinical Mycobacterium tuberculosis (MTB) isolates and analyze the associated risk factors in southwestern China. PATIENTS AND METHODS: Total 122 PAS-resistant and 55 PAS-susceptible clinical isolates were obtained from Chongqing Public Health Medical Center between April 2014 and January 2018. Drug susceptibility test was performed, and the PAS resistance-related genes were sequenced. RESULTS: PAS-resistant strains were more likely to resist streptomycin (OR: 9.5, 95% CI: 3.87-23.3; P<0.01), isoniazid (OR: 5.98, 95% CI: 2.14-16.76; P<0.01), rifampin (OR: 5.01, 95% CI: 2.11-11.88; P<0.01), ethambutol (OR: 2.79, 95% CI: 1.44-5.4; P<0.01), levofloxacin (OR: 2.56, 95% CI: 1.33-4.93; P<0.01), and amikacin (OR: 4.29, 95% CI: 1.70-10.83; P<0.01). The sequencing results showed that 112 (91.8%) PAS-resistant strains harbored 30 different mutations in folC, thyA, and ribD. Mutations in folC were the most commonly observed in PAS-resistant isolates (54.5%, 61/112), followed by mutations in thyA and ribD. Residues I43 in folC, R235 in thyA, and -11G in upstream of ribD were hotspots for mutation sites. CONCLUSION: PAS drug resistance in MTB in southwestern China is mainly caused by mutations in folC, thyA, and ribD, among which folC was the most frequent mutation. Some mutation hotspots exist in the three genes, which accounts for about 80% of total mutations. These results highlight the possibility of developing molecular diagnostic methods for PAS-resistant tuberculosis in the future.

[Influence of traditional Chinese compound recipes with different efficacy on body weight, tumor weight and immune function in H22 cancer-bearing mice].

OBJECTIVE: To compare the influence of traditional Chinese compound recipes (TCCRs) with different efficacy on body weight, tumor weight and immune function in H22 cancer-bearing mice. METHODS: H(22) cancer-bearing mice were chosen to observe the effects of TCCRs with different efficacy on tumor growth inhibition and detect the proliferation function of T lymphocytes, the activity of natural killer (NK) cells, the changes of T lymphocytes and the content of interferon-gamma (IFN-gamma)and interleukin-4 (IL-4). RESULTS: Tumor weight of H(22) cancer-bearing mice in Yidu Gongdu Recipe (YDGDR, a compound traditional Chinese herbal medicine using poison as an antidote for poison)-treated group was obviously lighter than that in the other TCCR-treated groups and the tumor inhibition rate in YDGDR-treated group was 65.76% (P<0.01). The tumor inhibition rates in other TCCR-treated groups were ranged from 10.1% to 17.1% . Body weight of mice in YDGDR-treated group was obviously decreased and depilation was observed at the same time. Pelage of mice in Fuzheng Peiben Recipe (FZPBR, a compound traditional Chinese herbal medicine for supporting the healthy energy)-treated group grew well, and behavior of the mice was active. Stimulation index (SI) of T lymphocyte transformation in YDGDR-treated group was obviously increased (SI=4.34, P<0.01), which showed the proliferation function of T lymphocyte was very strong. The SI of T lymphocyte transformation in the other groups was less than three, which showed the proliferation function of T lymphocytes was not significant. Compared with normal saline (NS)-treated group, percentages of NK cells in Qinre Jiedu Recipe (QRJDR, a compound traditional Chinese herbal medicine for clearing away heat and toxic substances)-treated, Huxue Huayu Recipe (HXHYR, a compound traditional Chinese herbal medicine for activating blood circulation to dissipate blood stasis)-treated and YDGDR-treated groups were obviously increased and 5.05, 4.07 and 5.17 times more than the NS-treated group, respectively (P<0.01). The activity of NK cells wasn't increased in the FZPBR-treated and HXHYR-treated groups. The production of IFN-gamma induced by T cells in YDGDR-treated group was obviously raised (P<0.05), and the production of IL-4 induced by T cells in QRJDR-treated, HXHYR-treated, Huatan Sanjie Recipe (a compound traditional Chinese herbal medicine for eliminating phlegm and resolving masses)-treated and YDGDR-treated groups was also raised obviously (P<0.01). CONCLUSION: YDGDR has a good effect of inhibiting tumor growth and can reinforce cellular and humoral immune function in tumor-bearing mice. FZPBR can strengthen the body.

Case report: incidental parathyroid adenoma in a Chinese diabetic patient with hypercalcemia and normal parathyroid hormone levels.

RATIONALE: Parathyroid hormone PTH) levels are the main parameters to differentiate primary hyperparathyroidism (PHPT) from non-PTH-dependent hypercalcemia. We report a case of hypercalcemia with normal PTH levels due to a parathyroid adenoma. PATIENT CONCERNS: A 52-year-old female patient presented with 2-year history of documented sustained high-normal serum calcium and hypercalcemia (2.51-3.03 mmol/L) with normal serum intact PTH levels (21.95-40.15 pg/ mL). DIAGNOSES: A parathyroid tumor was localized by ultrasonography and 99mTc-sestamibi dual-phase fusion imaging with single-photon emission computed tomography/computed tomography. INTERVENTIONS: Parathyroidectomy was performed to excise the tumor completely. OUTCOMES: A 1.2-cm-sized parathyroid adenoma was removed surgically. The serum calcium was declined to normal level immediately after resection, as well as in 4- month follow-ups. The immunohistological diagnosis proved to be a PTH positive parathyroid adenoma. LESSONS: In case of hypercalcemia, serum intact PTH and parathyroid imaging should be monitored to evaluate the presence of parathyroid adenoma with care because PHPT could present with inappropriate normal PTH.

p53 attenuates acetaminophen-induced hepatotoxicity by regulating drug-metabolizing enzymes and transporter expression.

Acetaminophen (APAP) overdose is the most frequent cause of drug-induced acute liver failure. Inhibition of APAP metabolic activation and promotion in APAP disposition are important to protect against APAP-induced liver injury. Tumor suppressor p53 is traditionally recognized as a surveillance molecule to preserve genome integrity. Recent studies have emerged on discovering its functions in metabolic regulation. Our previous study reported that p53 promoted bile acid disposition and alleviated cholestastic syndrome. Here, we examined the effect of doxorubicin (Dox)-mediated p53 activation on APAP-induced hepatotoxicity in mice and revealed a novel role of p53 in regulating APAP metabolism and disposition. Histopathological and biochemical assessments demonstrated that administration of Dox (10 mg/kg/d) before APAP treatment (400 mg/kg) significantly alleviated APAP-induced hepatotoxicity. Dox treatment prevented APAP-induced GSH depletion and lipid peroxidation. p53-null mice were more susceptible to APAP-induced liver injury. Further, we found that the expression of drug-metabolizing enzymes and transporters CYPs, SULTs and MRPs was regulated by p53. Dox treatment also promoted Nrf2 activation and increased the expression of Nrf2 target genes including GSTα/µ and NQO1, which contribute to APAP detoxification. Overall, this study is the first to demonstrate the protective role of p53 in regulating APAP metabolism and disposition, which provides a potential new therapeutic target for APAP-induced liver injury.

Carnitine palmitoyltransferase 1C regulates cancer cell senescence through mitochondria-associated metabolic reprograming.

Cellular senescence is a fundamental biological process that has profound implications in cancer development and therapeutics, but the underlying mechanisms remain elusive. Here we show that carnitine palmitoyltransferase 1C (CPT1C), an enzyme that catalyzes carnitinylation of fatty acids for transport into mitochondria for ß-oxidation, plays a major role in the regulation of cancer cell senescence through mitochondria-associated metabolic reprograming. Metabolomics analysis suggested alterations in mitochondria activity, as revealed by the marked decrease in acylcarnitines in senescent human pancreatic carcinoma PANC-1 cells, indicating low CPT1C activity. Direct analyses of mRNA and protein show that CPT1C is significantly reduced in senescent cells. Furthermore, abnormal mitochondrial function was observed in senescent PANC-1 cells, leading to lower cell survival under metabolic stress and suppressed tumorigenesis in a mouse xenograft model. Knock-down of CPT1C in PANC-1 cells induced mitochondrial dysfunction, caused senescence-like growth suppression and cellular senescence, suppressed cell survival under metabolic stress, and inhibited tumorigenesis in vivo. Further, CPT1C knock-down suppressed xenograft tumor growth in situ. Silencing of CPT1C in five other tumor cell lines also caused cellular senescence. On the contrary, gain-of-function of CPT1C reversed PANC-1 cell senescence and enhanced mitochondrial function. This study identifies CPT1C as a novel biomarker and key regulator of cancer cell senescence through mitochondria-associated metabolic reprograming, and suggests that inhibition of CPT1C may represent a new therapeutic strategy for cancer treatment through induction of tumor senescence.

A Golgi-associated protein 4.1B variant is required for assimilation of proteins in the membrane.

The archetypal membrane skeleton is that of the erythrocyte, consisting predominantly of spectrin, actin, ankyrin R and protein 4.1R. The presence in the Golgi of a membrane skeleton with a similar structure has been inferred, based on the identification of Golgi-associated spectrin and ankyrin. It has long been assumed that a Golgi-specific protein 4.1 must also exist, but it has not previously been found. We demonstrate here that a hitherto unknown form of protein 4.1, a 200 kDa 4.1B, is associated with the Golgi of Madin-Darby canine kidney (MDCK) and human bronchial epithelial (HBE) cells. This 4.1B variant behaves like a Golgi marker after treatment with Brefeldin A and during mitosis. Depletion of the protein in HBE cells by siRNA resulted in disruption of the Golgi structure and failure of Na(+)/K(+)-ATPase, ZO-1 and ZO-2 to migrate to the membrane. Thus, this newly identified Golgi-specific protein 4.1 appears to have an essential role in maintaining the structure of the Golgi and in assembly of a subset of membrane proteins.

[Study of HLA molecules and its associated genes expression in human ovarian cancer cells].

AIM: To explore the correlation between the expressions of HLA gene and its related gene, and expression of class II transactivator (CIITA) gene induced by IFN-gamma in human ovarian cells. METHODS: The expression of HLA molecule in the tumor cells was detected by Western blot, immunohistochemical staining and flow cytometry. The expressions of transporters associated with antigen processing (TAP), low molecular weight peptides (LMP), and CIITA genes were analyzed by RT-PCR. RESULTS: Abnormal expression rate of HLA class I molecule reached 45% in the 11 ovarian cancer cells. The expressed abnormalities of HLA class I molecule had relation to those of 4 genes (TAP1, TAP2, LMP2 and LMP7). Expression of HLA class II molecule was identical with that of CIITA gene in the ovarian cancer cells or other tumor cells. After IFN-gamma treatment, expressions of HLA class I and II molecule were increased in the cells of CIITA-expressing constitutively or inducibly, while no enhancement of HLA molecule expression manifested itself in the tumor cells of that CIITA was not yet expressed after IFN-gamma induction. CONCLUSION: Deletion of TAP and LMP gene expression in the ovarian cancer cells is an important factor causing abnormal expression of HLA class I molecule, suggesting that the CIITA gene has involved in the modulation of HLA classes I and II molecule expressions in the tumor cells.