Objective: We analyze the characteristics of Clostridioides difficile (C. difficile) infection among diarrhea patients in Kunming from 2018 to 2020 and provide evidence for follow-up surveillance and prevention. Methods: A total of 388 fecal samples of diarrhea patients from four sentinel hospitals in Yunnan Province from 2018 to 2020 were collected. Real-time quantitative PCR was used to detect the fecal toxin genes of C. difficile. The positive fecal samples isolated the bacteria, and isolates were identified by mass spectrometry. The genomic DNA of the strains was extracted for multi-locus sequence typing (MLST). The fecal toxin, strain isolation, and clinical patient characteristics, including co-infection with other pathogens, were analyzed. Results: Among the 388 fecal samples, 47 samples with positive reference genes of C. difficile were positive, with a total positive rate of 12.11%. There were 4 (8.51%) non-toxigenic and 43 (91.49%) toxigenic ones. A total of 18 strains C. difficile were isolated from 47 positive specimens, and the isolation rate of positive specimens was 38.30%. Among them, 14 strains were positive for tcdA, tcdB, tcdC, tcdR, and tcdE. All 18 strains of C. difficile were negative for binary toxins. The MLST results showed 10 sequence types (ST), including 5 strains of ST37, accounting for 27.78%; 2 strains of ST129, ST3, ST54, and ST2, respectively; and 1 strain of ST35, ST532, ST48, ST27, and ST39, respectively. Fecal toxin gene positive (tcdB+) results were statistically associated with the patient's age group and with or without fever before the visit; positive isolates were only statistically associated with the patient's age group. In addition, some C. difficile patients have co-infection with other diarrhea-related viruses. Conclusions: The infection of C. difficile in diarrhea patients in Kunming is mostly toxigenic strains, and the high diversity of strains was identified using the MLST method. Therefore, the surveillance and prevention of C. difficile should be strengthened.
Humans ; Bacterial Toxins/genetics* ; Enterotoxins/genetics* ; Clostridioides difficile/genetics* ; Multilocus Sequence Typing ; Coinfection ; Bacterial Proteins/genetics* ; China/epidemiology* ; Clostridium Infections/epidemiology* ; Diarrhea/microbiology*

Objective: To establish and optimize PCR methods for the gene encoding of Clostridium perfringens β₂ toxin (cpb₂) and atypical-cpb₂ (aty-cpb₂), analyze the epidemiological characteristics and genetic polymorphism of the cpb₂ of Clostridium perfringens in 9 Chinese areas from 2016 to 2021. Methods: The cpb₂ of 188 Clostridium perfringens strains were examined by PCR; the cpb₂ sequences were acquired by whole-genome sequencing to analyze the genetic polymorphism. Using Mega 11 and the Makeblastdb tool, a phylogenetic tree, and cpb₂-library based on 110 strains carrying the cpb₂ were produced. Using the Blastn technique, a comparison was made to discover sequence similarity between consensus-cpb₂ (con-cpb₂) and aty-cpb₂. Results: The specificity of PCR assay for the cpb₂ and aty-cpb₂ was verified. The PCR results for cpb₂ amplification were highly consistent with the whole-genome sequencing approach (Kappa=0.946, P<0.001). A total of 107 strains from nine regions in China carried cpb₂, 94 types A strains carried aty-cpb₂, 6 types A strains carried con-cpb₂, and 7 types F strains carried aty-cpb₂. The nucleotide sequence similarity between the two coding genes was 68.97%-70.97%, and the similarity between the same coding genes was 98.00%-100.00%. Conclusions: In this study, a specific PCR method for cpb₂ toxin was developed, and the previous PCR method for detecting aty-cpb₂ was improved. aty-cpb₂ is the primary gene encoding of β₂ toxin. There is a significant nucleotide sequence variance between the various cpb₂ genotypes.
Humans ; Clostridium perfringens/genetics* ; Clostridium Infections ; Bacterial Toxins/genetics* ; Phylogeny ; Polymerase Chain Reaction ; Polymorphism, Genetic

Humans ; Esophagus ; Manometry ; Botulinum Toxins/therapeutic use* ; Prostheses and Implants ; Treatment Outcome ; Larynx, Artificial

Spasticity is one of the most common and disabling complications of stroke. Most of these patients notably experience both muscle-based and non-muscle-based pain. This negatively affects their quality of life as well as aggravates caregiver burden. Post-stroke spasticity (PSS) may furthermore lead to several complications related to limited mobility, both motor (eg, contractures) and non-motor (cognitive decline, depression) if left untreated. It is thus crucial to address this with safe and effective means such as botulinum toxin therapy as early as possible. We aim to demonstrate the utility of botulinum toxin (BoNT) in PSS treatment and how early intervention may be preferable to late spasticity control for patients. Literature search and evaluation were done using the traditional evidence hierarchy. Early intervention with botulinum toxin A (BoNTA) demonstrated a more marked reduction in both spasticity and spasticity-related pain with longer required intervals to reinjection.
Botulinum Toxins ; Pain

Humans ; Botulinum Toxins, Type A/therapeutic use* ; Esotropia/drug therapy* ; Neuromuscular Agents ; Injections ; Treatment Outcome ; Oculomotor Muscles

Bt Cry toxin is the mostly studied and widely used biological insect resistance protein, which plays a leading role in the green control of agricultural pests worldwide. However, with the wide application of its preparations and transgenic insecticidal crops, the resistance to target pests and potential ecological risks induced by the drive are increasingly prominent and attracting much attention. The researchers seek to explore new insecticidal protein materials that can simulate the insecticidal function of Bt Cry toxin. This will help to escort the sustainable and healthy production of crops, and relieve the pressure of target pests' resistance to Bt Cry toxin to a certain extent. In recent years, the author's team has proposed that Ab2β anti-idiotype antibody has the property of mimicking antigen structure and function based on the "Immune network theory" of antibody. With the help of phage display antibody library and specific antibody high-throughput screening and identification technology, Bt Cry toxin antibody was designed as the coating target antigen, and a series of Ab2β anti-idiotype antibodies (namely Bt Cry toxin insecticidal mimics) were screened from the phage antibody library. Among them, the lethality of Bt Cry toxin insecticidal mimics with the strongest activity was close to 80% of the corresponding original Bt Cry toxin, showing great promise for the targeted design of Bt Cry toxin insecticidal mimics. This paper systematically summarized the theoretical basis, technical conditions, research status, and discussed the development trend of relevant technologies and how to promote the application of existing achievements, aiming to facilitate the research and development of green insect-resistant materials.
Insecticides/metabolism* ; Bacillus thuringiensis ; Endotoxins/pharmacology* ; Bacillus thuringiensis Toxins/metabolism* ; Hemolysin Proteins/pharmacology* ; Bacterial Proteins/chemistry* ; Plants, Genetically Modified/genetics* ; Pest Control, Biological

OBJECTIVES: At present, there are many reports about the treatment of cricopharyngeal achalasia by injecting botulinum toxin type A (BTX-A) into cricopharyngeal muscle guided by ultrasound, electromyography or CT in China, but there is no report about injecting BTX-A into cricopharyngeal muscle guided by endoscope. This study aims to evaluate the efficacy of endoscopic BTX-A injection combined with balloon dilatation in the treatment of cricopharyngeal achalasia after brainstem stroke, and to provide a better method for the treatment of dysphagia after brainstem stroke. METHODS: From June to December 2022, 30 patients with cricopharyngeal achalasia due to brainstem stroke were selected from the Department of Rehabilitation Medicine, the First Hospital of Changsha. They were randomly assigned into a control group and a combined group, 15 patients in each group. Patients in both groups were treated with routine rehabilitation therapy, while patients in the control group were treated with balloon dilatation, and patients in the combined group were treated with balloon dilatation and BTX-A injection. Before treatment and after 2 weeks of treatment, the patients were examined by video fluoroscopic swallowing study, Penetration-aspiration Scale (PAS), Dysphagia Outcome Severity Scale (DOSS), and Functional Oral Intake Scale (FOIS) were used to assess the swallowing function. RESULTS: In the combined group, 1 patient withdrew from the treatment because of personal reasons. Two weeks after treatment, the scores of DOSS, PAS, and FOIS in both groups were better than those before treatment (all P<0.01), and the combined group was better than the control group (all P<0.001). The effective rate was 85.7% in the combined group and 66.7% in the control group, with no significant difference between the 2 groups (P>0.05). CONCLUSIONS BTX-A injection combined with balloon dilatation is more effective than balloon dilatation alone in improving swallowing function and is worthy of clinical application.
Humans ; Deglutition Disorders/therapy* ; Esophageal Achalasia/drug therapy* ; Dilatation/adverse effects* ; Botulinum Toxins, Type A/therapeutic use* ; Brain Stem Infarctions/drug therapy* ; Treatment Outcome

Bacteria are often infected by large numbers of phages, and host bacteria have evolved diverse molecular strategies in the race with phages, with abortive infection (Abi) being one of them. The toxin-antitoxin system (TA) is expressed in response to bacterial stress, mediating hypometabolism and even dormancy, as well as directly reducing the formation of offspring phages. In addition, some of the toxins' sequences and structures are highly homologous to Cas, and phages even encode antitoxin analogs to block the activity of the corresponding toxins. This suggests that the failure of phage infection due to bacterial death in abortive infections is highly compatible with TA function, whereas TA may be one of the main resistance and defense forces for phage infestation of the host. This review summarized the TA systems involved in phage abortive infections based on classification and function. Moreover, TA systems with abortive functions and future use in antibiotic development and disease treatment were predicted. This will facilitate the understanding of bacterial-phage interactions as well as phage therapy and related synthetic biology research.
Anti-Bacterial Agents ; Antitoxins/chemistry* ; Bacteria/genetics* ; Bacterial Proteins/chemistry* ; Bacterial Toxins/genetics* ; Bacteriophages/genetics* ; Toxin-Antitoxin Systems/genetics*

The main cause of death in patients with end-stage renal disease (ESRD) is cardiovascular disease, and trimethylamine-N-oxide (TMAO) has been found to be one of the specific risk factors in the pathogenic process in recent years. TMAO is derived from intestinal bacterial metabolism of dietary choline, carnitine and other substances and subsequently catalyzed by flavin monooxygenase enzymes in the liver. The changes of intestinal bacteria in ESRD patients have contributed to the accumulation of gut-derived uremic toxins such as TMAO, indoxyl sulfate and indole-3-acetic acid. While elevated TMAO concentration accelerates atherosclerosis through mechanisms such as inflammation, increased scavenger receptor expression, and inhibition of reverse cholesterol transport. In this review, this research introduces the biological function, metabolic processes of TMAO and mechanisms by which TMAO promotes the progression of cardiovascular disease in ESRD patients and summarizes current interventions that may be used to reverse gut microbiota disturbances, such as activated carbon, fecal microbial transplantation, dietary improvement, probiotic and probiotic introduction. It also focuses on exploring intervention targets to reduce the gut-derived uremic toxin TMAO in order to explore the possibility of more cardiovascular disease treatments for ESRD patients.
Cardiovascular Diseases ; Humans ; Kidney Failure, Chronic ; Methylamines ; Oxides ; Uremic Toxins

Clostridium difficile is an important zoonotic intestinal pathogen, which is widely present in humans and a variety of animals. The ST11 type C. difficile is one of the most widespread and harmful subtypes in the world. As a large country in pig farming, China lacks efficient methods for detecting C. difficile of porcine origin, leaving hidden dangers for the prevention and control of C. difficile. The aim of this study was to develop a specific and sensitive double-antibody sandwich ELISA for the epidemiological investigation of ST11 type C. difficile of porcine origin. Firstly, a 97 kDa receptor binding domain (RBD) was expressed in a prokaryotic host and purified. A hybridoma cell line AE2D3 capable of stably secreting monoclonal antibody targeting the RBD was screened, and the antibody subtype was determined to be IgG2b (κ). Secondly, a double antibody sandwich ELISA method was developed, where the monoclonal antibody targeting the RBD was used as a detection antibody, and the rabbit polyclonal antibody was used as a capture antibody. The chessboard method was used to determine the matching concentration of the capture antibody and the detection antibody, the antigen coating conditions, the blocking conditions, the incubation conditions for detection antibody and samples to be tested, as well as the reaction conditions of HRP-conjugated and reaction conditions of TMB chromogenic solution. The negative cutoff OD₄₅₀ was 0.152, and no cross-reaction with 13 strains of non-ST11 type C. difficile was found. The minimum detection concentration of RBD was 8.83 ng/mL. This specific and sensitive double-antibody sandwich ELISA provides a reliable serological detection method for epidemiological investigation of the ST11 type C. difficile in pig industry.
Animals ; Antibodies, Monoclonal ; Bacterial Proteins/genetics* ; Bacterial Toxins ; Clostridioides difficile ; Enzyme-Linked Immunosorbent Assay ; Hybridomas ; Swine