Histone deacetylase inhibitor pracinostat suppresses colorectal cancer by inducing CDK5-Drp1 signaling-mediated peripheral mitofission / 药物分析学报

Divisions at the periphery and midzone of mitochondria are two fission signatures that determine the fate of mitochondria and cells.Pharmacological induction of excessively asymmetric mitofission-associated cell death(MFAD)by switching the scission position from the mitochondrial midzone to the periphery represents a promising strategy for anticancer therapy.By screening a series of pan-inhibitors,we identified pracinostat,a pan-histone deacetylase(HDAC)inhibitor,as a novel MFAD inducer,that exhibited a significant anticancer effect on colorectal cancer(CRC)in vivo and in vitro.Pracinostat increased the expression of cyclin-dependent kinase 5(CDK5)and induced its acetylation at residue lysine 33,accelerating the formation of complex CDK5/CDK5 regulatory subunit 1 and dynamin-related protein 1(Drp1)-mediated mitochondrial peripheral fission.CRC cells with high level of CDK5(CDK5-high)displayed midzone mitochondrial division that was associated with oncogenic phenotype,but treatment with pracinostat led to a lethal increase in the already-elevated level of CDK5 in the CRC cells.Mechanistically,pracinostat switched the scission position from the mitochondrial midzone to the periphery by improving the binding of Drp1 from mitochondrial fission factor(MFF)to mitochondrial fission 1 protein(FIS1).Thus,our results revealed the anticancer mechanism of HDACi pracinostat in CRC via activating CDK5-Drp1 signaling to cause selective MFAD of those CDK5-high tumor cells,which implicates a new paradigm to develop potential therapeutic strategies for CRC treatment.

Analysis of fast-growing culturable bacteria and pathogenic bacteria in the surface water of the northeast coast of Hainan Island in China / 中华预防医学杂志

Objective: To obtain the diversity and abundance of fast-growing bacteria in the surface water of the northeast coast of Hainan Island in China, different cultivation methods were employed. This study also aims to provide a reference for isolating bacterial samples from seawater sources and preventing marine-derived pathogens. Methods: Based on the principles of taxonomic design, surface seawater samples were collected from six locations along the northeast coast of Hainan Island in China in March, June, October, and December 2021. Then, bacterial enrichment was performed based on traditional cultivation methods for Salmonella, Vibrio, Burkholderia pseudomallei, Actinomycetes, and general marine bacteria. After that, bacterial species identification was conducted by 16S rDNA amplicon sequencing and metagenomic sequencing. Results: A total of 1 151 fast-growing cultivable bacteria belonging to 66 genera and 213 species were identified using five different culture protocols. In different cultivation protocols, Bacillus and Klebsiella demonstrated extensive discriminatory advantages and ranked among the top genera in terms of abundance. Protocol 1 had Escherichia, Klebsiella, and Citrobacter as dominant genera. Pathogenic bacteria detected by protocol 1 included Klebsiella pneumoniae and Escherichia coli, with 37 and 29 strains respectively, while Salmonella enterica was uniquely detected with seven isolates. Proteus, Enterococcus, and Providencia were the dominant genera in protocol 2, and Proteus mirabilis was the most abundant pathogenic bacteria detected with 66 isolates. Vibrio cholerae was uniquely detected with six isolates at a higher abundance. Klebsiella, Escherichia, and Acinetobacter were the dominant genera in protocol 3, and Klebsiella pneumoniae was the most abundant pathogenic bacteria detected with 53 isolates, while Acinetobacter nosocomialis was uniquely detected with seven isolates. Vibrio and Pseudoalteromonas were the dominant genera in protocol 4, and they showed advantages in isolating and cultivating Marine-derived Vibrio. Exiguobacterium, Staphylococcus, and Bacillus were the dominant genera in protocol 5. Bacillus cereus and Lactococcus lactis were the most abundant pathogenic bacteria detected with 20 and 15 isolates, respectively, while Lactococcus lactis was uniquely detected at higher abundance. Metagenomic sequencing showed that Klebsiella pneumoniae was significantly dominant with a gene abundance of 51.11%, followed by Alcanivorax sp. at 12.57%. Conclusion: The surface water of the northeast coast of Hainan Island in China exhibits a rich diversity of bacteria, with Klebsiella pneumoniae being highly abundant in the studied area. Different cultivation methods demonstrate distinct selective advantages in culturing bacterial genera and pathogens. Therefore, it is necessary to optimize cultivation conditions for specific marine bacteria.

Analysis of fast-growing culturable bacteria and pathogenic bacteria in the surface water of the northeast coast of Hainan Island in China / 中华预防医学杂志

Objective: To obtain the diversity and abundance of fast-growing bacteria in the surface water of the northeast coast of Hainan Island in China, different cultivation methods were employed. This study also aims to provide a reference for isolating bacterial samples from seawater sources and preventing marine-derived pathogens. Methods: Based on the principles of taxonomic design, surface seawater samples were collected from six locations along the northeast coast of Hainan Island in China in March, June, October, and December 2021. Then, bacterial enrichment was performed based on traditional cultivation methods for Salmonella, Vibrio, Burkholderia pseudomallei, Actinomycetes, and general marine bacteria. After that, bacterial species identification was conducted by 16S rDNA amplicon sequencing and metagenomic sequencing. Results: A total of 1 151 fast-growing cultivable bacteria belonging to 66 genera and 213 species were identified using five different culture protocols. In different cultivation protocols, Bacillus and Klebsiella demonstrated extensive discriminatory advantages and ranked among the top genera in terms of abundance. Protocol 1 had Escherichia, Klebsiella, and Citrobacter as dominant genera. Pathogenic bacteria detected by protocol 1 included Klebsiella pneumoniae and Escherichia coli, with 37 and 29 strains respectively, while Salmonella enterica was uniquely detected with seven isolates. Proteus, Enterococcus, and Providencia were the dominant genera in protocol 2, and Proteus mirabilis was the most abundant pathogenic bacteria detected with 66 isolates. Vibrio cholerae was uniquely detected with six isolates at a higher abundance. Klebsiella, Escherichia, and Acinetobacter were the dominant genera in protocol 3, and Klebsiella pneumoniae was the most abundant pathogenic bacteria detected with 53 isolates, while Acinetobacter nosocomialis was uniquely detected with seven isolates. Vibrio and Pseudoalteromonas were the dominant genera in protocol 4, and they showed advantages in isolating and cultivating Marine-derived Vibrio. Exiguobacterium, Staphylococcus, and Bacillus were the dominant genera in protocol 5. Bacillus cereus and Lactococcus lactis were the most abundant pathogenic bacteria detected with 20 and 15 isolates, respectively, while Lactococcus lactis was uniquely detected at higher abundance. Metagenomic sequencing showed that Klebsiella pneumoniae was significantly dominant with a gene abundance of 51.11%, followed by Alcanivorax sp. at 12.57%. Conclusion: The surface water of the northeast coast of Hainan Island in China exhibits a rich diversity of bacteria, with Klebsiella pneumoniae being highly abundant in the studied area. Different cultivation methods demonstrate distinct selective advantages in culturing bacterial genera and pathogens. Therefore, it is necessary to optimize cultivation conditions for specific marine bacteria.

Follow up analysis of 6 patients with severe trimethyltin chloride poisoning for 4 years / 中华劳动卫生职业病杂志

Objective: Objective to investigate the health changes of patients with severe trimethyltin chloride (TMT) poisoning in four years. Methods: Six patients with severe TMT poisoning treated in the First Affiliated Hospital of Gannan Medical College in August 2016 were numbered 1, 2, 3, 4, 5 and 6 respectively. The patients were followed up 0.5, 2 and 4 years after poisoning and compared and analyzed. The follow-up contents include: symptom degree, score of simple mental intelligence examination scale (MMSE) and modified Rankin Scale (MRS) , cranial magnetic resonance imaging (MRI) , EEG, etc. Results: The symptoms of dizziness, headache, chest tightness, palpitation, nausea and vomiting decreased gradually in 6 patients. The symptoms of speech disorder and memory decline in No.1, 2 and 3 patients gradually increased, and the scores of MMSE and Mrs gradually decreased; Patients No.4, 5 and 6 had improved speech disorder, but their memory decreased, MMSE and Mrs scores were still flat, and mild cognitive impairment. The brain atrophy of No.1, 2 and 3 patients was aggravated, which showed obvious atrophy of hippocampus, temporal lobe, insular lobe and cerebellum and enlargement of ventricle; There was no significant change in brain atrophy in No.4, 5 and 6 patients. Conclusion: The neurotoxic symptoms in the later stage of severe TMT poisoning are still serious, and the neurotoxic time is long.