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1.
Bioorg Chem ; 143: 106983, 2024 Feb.
Article En | MEDLINE | ID: mdl-38016396

RNA polymerase is an essential enzyme involved in bacterial transcription, playing a crucial role in RNA synthesis. However, it requires the association with sigma factors to initiate this process. In our previous work, we utilized a structure-based drug discovery approach to create benzoyl and benzyl benzoic acid compounds. These compounds were designed based on the amino acid residues within the key binding site of sigma factors, which are crucial for their interaction with RNA polymerase. By inhibiting bacterial transcription, these compounds exhibited notable antimicrobial activity, and we coined them as sigmacidins to highlight their resemblance to sigma factors and the benzoic acid structure. In this study, we further modified the compound scaffolds and developed a series of sulfonamidyl benzoic acid derivatives. These derivatives displayed potent antimicrobial activity, with minimum inhibitory concentrations (MICs) as low as 1 µg/mL, demonstrating their efficacy against bacteria. Furthermore, these compounds demonstrated low cytotoxicity, indicating their potential as safe antimicrobial agents. To ascertain their mechanism of action in interfering with bacterial transcription, we conducted biochemical and cellular assays. Overall, this study showcases the effectiveness of sulfonamidyl benzoic acid derivatives as antimicrobial agents by targeting protein-protein interactions involving RNA polymerase and sigma factors. Their strong antimicrobial activity and low cytotoxicity implicate their potential in combating antibiotic-resistant bacteria.


Anti-Bacterial Agents , Anti-Infective Agents , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry , Sigma Factor/metabolism , DNA-Directed RNA Polymerases/metabolism , Bacteria/metabolism , Benzoic Acid/pharmacology , Microbial Sensitivity Tests
2.
J Org Chem ; 87(13): 8802-8810, 2022 07 01.
Article En | MEDLINE | ID: mdl-35723444

Functionalized aryl sulfonamides are important building blocks in the pharmaceutical industry. A one-step synthesis catalyzed by a copper salt was developed using stable solid commodity chemicals in sulfolane or, alternatively, in green solvents such as γ-valerolactone, iPrOAc, or nBuOAc with acetic acid. The method tolerated diverse functional groups commonly presented in current medicines and drug intermediates. The mechanistic study showed a radical coupling pathway between the sulfonyl and anilinium radicals through the use of K2S2O8 and copper catalyst, respectively.


Copper , Sulfonamides , Catalysis , Ions , Sodium , Solvents
3.
Diabetes Obes Metab ; 23(4): 897-909, 2021 04.
Article En | MEDLINE | ID: mdl-33319467

AIMS: To develop and validate 10-year risk prediction models, nomograms and charts for end-stage renal disease (ESRD) in Chinese patients with type 2 diabetes mellitus (T2DM) in primary care, in order to guide individualized treatment. MATERIALS AND METHODS: This was a 10-year population-based observational cohort study. A total of 141 516 Chinese T2DM patients without history of cardiovascular disease or ESRD who were managed in public primary care clinics in 2008 were included and followed up until December 2017. Two-thirds of these patients were randomly selected to develop sex-specific ESRD risk prediction models using Cox regressions. The validity and accuracy of the models were tested on the remaining third of patients using Harrell's C-index. We selected variables based on their clinical and statistical importance to construct the nomograms and charts. RESULTS: The median follow-up period was 9.75 years. The cumulative incidence of ESRD was 6.0% (men: 6.1%, women: 5.9%). Age, diabetes duration, systolic blood pressure (SBP), SBP variability, diastolic blood pressure, triglycerides, glycated haemoglobin (HbA1c), HbA1c variability, urine albumin to creatinine ratio (UACR), and estimated glomerular filtration rate (eGFR) were significant predictors for both sexes. Smoking and total cholesterol to HDL cholesterol ratio were additional significant predictors for men and women, respectively. The models showed Harrell's C-statistics of 0.889/0.889 (women/men). Age, eGFR, UACR, SBP and HbA1c were selected for both sexes to develop nomograms and charts. CONCLUSIONS: Using routinely available variables, the 10-year ESRD risk of Chinese T2DM patients in primary care can be predicted with approximately 90% accuracy. We have developed different tools to facilitate routine ESRD risk prediction in primary care, so that individualized care can be provided to prevent or delay ESRD in T2DM patients.


Diabetes Mellitus, Type 2 , Kidney Failure, Chronic , China/epidemiology , Diabetes Mellitus, Type 2/complications , Diabetes Mellitus, Type 2/epidemiology , Female , Glomerular Filtration Rate , Humans , Kidney Failure, Chronic/epidemiology , Kidney Failure, Chronic/etiology , Male , Nomograms , Primary Health Care , Retrospective Studies , Risk Factors
4.
Clin Gastroenterol Hepatol ; 17(7): 1303-1310.e18, 2019 06.
Article En | MEDLINE | ID: mdl-29654915

BACKGROUND & AIMS: The Chinese herbal medicine, MaZiRenWan (MZRW), has been used for more than 2000 years to treat constipation, but it has not been tested in a randomized controlled trial. We performed a trial to evaluate the efficacy and safety of MZRW, compared with the stimulant laxative senna or placebo, for patients with functional constipation (FC). METHODS: We performed a double-blind, double-dummy, trial of 291 patients with FC based on Rome III criteria, seen at 8 clinics in Hong Kong from June 2013 through August 2015. Patients were observed for 2 weeks and then assigned randomly (1:1:1) to groups given MZRW (7.5 g, twice daily), senna (15 mg daily), or placebo for 8 weeks. Patients were then followed for 8 weeks and evaluated at baseline and weeks 4, 8 (end of treatment), and 16 (end of follow up). Participants recorded information on stool form and frequency, feeling of complete evacuation, and research medication taken. Data on individual bowel symptoms, global symptom improvement, and adverse events were collected. A complete response was defined as an increase ≥1 complete spontaneous bowel movement (CSBM)/week from baseline (the primary outcome). Secondary outcomes included response during the follow-up period, colonic transit, individual and global symptom assessments, quality of life measured with 36-item short form Chinese version, and adverse events. RESULTS: Although there was no statistically significant difference in proportions of patients with a complete response to MZRW (68%) vs. senna (57.7%) (P = .14) at week 8, there was a statistically significant difference vs. placebo (33.0%) (P < .005). At the 16-week timepoint (after the 8-week follow-up period), 47.4% of patients had a complete response to MZRW, 20.6% had a complete response to senna, and 17.5% had a complete response to placebo (P < .005 for MZRW vs. placebo). The group that received MZRW group also had significant increases in colonic transit and reduced severity of constipation, straining, incomplete evacuation, and global constipation symptoms compared with the groups that received placebo or senna in (P < .05 for all comparisons). CONCLUSIONS: In a randomized controlled trial of 291 patients with FC, we found MZRW to be well-tolerated and effective in increasing CSBM/week. MZRW did not appear to be more effective than senna and might be considered as an alternative to this drug. ClincialTrials.gov no: NCT01695850.


Constipation/drug therapy , Defecation/drug effects , Drugs, Chinese Herbal/therapeutic use , Quality of Life , Constipation/physiopathology , Dose-Response Relationship, Drug , Double-Blind Method , Female , Follow-Up Studies , Humans , Male , Middle Aged , Retrospective Studies , Treatment Outcome
5.
BMJ Open ; 8(10): e023070, 2018 10 15.
Article En | MEDLINE | ID: mdl-30327405

INTRODUCTION: Diabetes mellitus (DM) is a major disease burden worldwide because it is associated with disabling and lethal complications. DM complication risk assessment and stratification is key to cost-effective management and tertiary prevention for patients with diabetes in primary care. Existing risk prediction functions were found to be inaccurate in Chinese patients with diabetes in primary care. This study aims to develop 10-year risk prediction models for total cardiovascular diseases (CVD) and all-cause mortality among Chinese patients with DM in primary care. METHODS AND ANALYSIS: A 10-year cohort study on a population-based primary care cohort of Chinese patients with diabetes, who were receiving care in the Hospital Authority General Outpatient Clinic on or before 1 January 2008, were identified from the clinical management system database of the Hospital Authority. All patients with complete baseline risk factors will be included and followed from 1 January 2008 to 31 December 2017 for the development and validation of prediction models. The analyses will be carried out separately for men and women. Two-thirds of subjects will be randomly selected as the training sample for model development. Cox regressions will be used to develop 10-year risk prediction models of total CVD and all-cause mortality. The validity of models will be tested on the remaining one-third of subjects by Harrell's C-statistics and calibration plot. Risk prediction models for diabetic complications specific to Chinese patients in primary care will enable accurate risk stratification, prioritisation of resources and more cost-effective interventions for patients with DM in primary care. ETHICS AND DISSEMINATION: The study was approved by the Institutional Review Board of the University of Hong Kong-the Hospital Authority Hong Kong West Cluster (reference number: UW 15-258). TRIAL REGISTRATION NUMBER: NCT03299010; Pre-results.


Diabetes Complications/epidemiology , Diabetes Mellitus/mortality , Risk Assessment , Adult , China/ethnology , Clinical Protocols , Diabetes Complications/etiology , Diabetes Complications/mortality , Female , Hong Kong/epidemiology , Humans , Male , Models, Statistical , Primary Health Care/statistics & numerical data , Proportional Hazards Models , Retrospective Studies , Risk Factors
6.
Trials ; 14: 366, 2013 Nov 04.
Article En | MEDLINE | ID: mdl-24180235

BACKGROUND: Functional constipation is a common clinical complaint. Although the effectiveness of Ma Zi Ren Wan for alleviating functional constipation symptoms has been proven in a previous randomized placebo-controlled study, further evidence is needed to make clinical recommendations about Chinese herbal medicine. In particular, a comparison with conventional western medicine for functional constipation patients is needed. METHODS/DESIGN: This is a prospective, double-blinded, double dummy, randomized, controlled trial. After a 2-week run-in period, eligible patients (Rome III) with excessive traditional Chinese medicine syndrome will randomly be assigned to the Chinese medicine arm (Ma Zi Ren Wan and western medicine placebo), western medicine arm (senna and Chinese medicine placebo) or placebo arm (Chinese medicine placebo and western medicine placebo). Patients will undergo an 8-week treatment and an 8-week follow-up. The primary outcome is the responder rate for complete spontaneous bowel movement (CSBM) during treatment. Patients with a mean increase of CSBM ≧1/week in comparison with their baselines are defined as responders. The secondary outcomes include responder rate during follow-up, changes of colonic transit as measured with radio-opaque markers, individual and global symptom assessments, and reported adverse effects. DISCUSSION: This study is the first study to compare a Chinese Herbal Medicine (Ma Zi Ren Wan) with a laxative that is commonly used in the clinical practice of western medicine, and with a placebo. This study will complete the investigation of Ma Zi Ren Wan for functional constipation, and should, therefore, suggest recommendations for clinical practice. Furthermore, the process of first conducting a systematic review, then implementing a dose determination study followed by a placebo-control trial, and finally, comparing traditional Chinese medicine with an active conventional medicine in a controlled trial can be a reference to other researches on Chinese medicine interventions in the future. TRIAL REGISTRATION: NCT01695850.


Constipation/therapy , Defecation/drug effects , Drugs, Chinese Herbal/therapeutic use , Laxatives/therapeutic use , Research Design , Senna Extract/therapeutic use , Clinical Protocols , Constipation/diagnosis , Constipation/physiopathology , Double-Blind Method , Drugs, Chinese Herbal/adverse effects , Gastrointestinal Motility/drug effects , Hong Kong , Humans , Laxatives/adverse effects , Prospective Studies , Recovery of Function , Senna Extract/adverse effects , Time Factors , Treatment Outcome
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