Novel directions of precision oncology:circulating microbial DNA emerging in cancer-microbiome areas

Microbiome research has extended into the cancer area in the past decades.Microbes can affect oncogenesis,progression,and treatment response through various mechanisms,including direct regulation and indirect impacts.Microbiota-associated detectionmethods and agents have been developed to facilitate cancer diagnosis and therapy.Additionally,the cancermicrobiome has recently been redefined.The identification of intra-tumoral microbes and cancer-related circulating microbial DNA(cmDNA)has promoted novel research in the cancer–microbiome area.In this review,we define the human system of commensal microbes and the cancer microbiome from a brand-new perspective and emphasize the potential value of cmDNA as a promising biomarker in cancer liquid biopsy.We outline all existing studies on the relationship between cmDNA and cancer and the outlook for potential preclinical and clinical applications of cmDNA in cancer precision medicine,as well as critical problems to be overcome in this burgeoning field.

Brain abscess caused by Streptococcus anginosus group:Three case reports

BACKGROUND This case series investigated the clinical manifestations,diagnoses,and treatment of cerebral abscesses caused by Streptococcus anginosus.We retrospectively analyzed the clinical characteristics and outcomes of three cases of cerebral abscesses caused by Streptococcus anginosus and conducted a comprehensive review of relevant literature.CASE SUMMARY Case 1 presented with a history of left otitis media and exhibited high fever,confusion,and vomiting as primary symptoms.Postoperative pus culture indicated a brain abscess caused by Streptococcus constellatus infection.Case 2 experienced dizziness for two days as the primary symptom.Postoperative pus culture suggested an intermediate streptococcal brain abscess.Case 3:Enhanced head magnetic resonance imaging(MRI)and diffusion-weighted imaging revealed occupancy of the left temporal lobe,initially suspected to be a metastatic tumor.However,a postoperative pus culture confirmed the presence of a brain abscess caused by Streptococcus anginosus infection.The three cases presented in this case series were all patients with community-acquired brain abscesses resulting from angina caused by Streptococcus group infection.All three patients demonstrated sensitivity to penicillin,ceftriaxone,vancomycin,linezolid,chloramphenicol,and levofloxacin.Successful treatment was achieved through stereotaxic puncture,drainage,and ceftriaxone administration with a six-week course of antibiotics.CONCLUSION Preoperative enhanced head MRI plays a critical role in distinguishing brain tumors from abscesses.Selecting the correct early diagnostic methods for brain abscesses and providing timely intervention are very important.This case series was in accordance with the CARE guidelines.

Hydrothermal carbonization of livestock mortality for the reduction of pathogens and microbially-derived DNA

Hydrothermal carbonization （HTC）, utilizing high temperature and pressure, has the potential to treat agricultural waste via inactivating pathogens, antibiotic resistance genes （ARG）, and contaminants of emerging concern （CEC） in a environmental and economical manner. Livestock mortality is one facet of agricultural waste that can pose a threat to the surrounding environment. While several methods are utilized to treat livestock mortality, there remains a paucity of data on the elimination of microbially- derived DNA in these treatment practices. This DNA, most notably ARGs, if it survives treatment can be reintroduced in agricultural environments where it could potentially be passed to pathogens, posing a risk to animal and human populations. HTC treatments have been successfully utilized for the treatment of CECs, however very little is understood on how ARGs survive HTC treatment. This study aims to fill this knowledge gap by examining the survivability ofmicrobially-derived DNA in the HTC treatment of livestock mortality. We examined three treatment temperatures （100℃, 150℃, and 200℃） at autogenic pressures at three treatment times （30, 60, and 240 min）. We examined the amplification of a plasmid-bome reporter gene carried by Escherichia coli DH 10B introduced to both beef bone and tissue. Results indicate that while all three temperatures, at all treatment times, were suitable for complete pathogen kill, only temperatures of 150℃ and 200℃ were sufficient for eliminating microbial DNA. These results serve as the basis for future potential HTC treatment recommendations for livestock mortality when considering the elimination of pathogens and ARGs.

携带新SCCmec型别菌株的耐药特点及PCR图谱多位点序列分析

目的了解前期研究中发现的3株携带有新型SCCmec聚合酶链反应(PCR)谱型的耐甲氧西林金黄色葡萄球菌(MRSA)的位点序列特性。方法在前期的分型研究中,从58株MRSA中检测到3株(5.17%)携带了一种新的SCCmec多位点PCR谱型,其含有5条扩增带,依次为A、F、H、B和M。对上述扩增产物测序,用BLAST与国际基因库内已知位点序列进行对比分析。结果测得序列与已有位点相应序列的同源性均在97%以上。结论此型为一新的SCCmec多位点PCR谱型,是传统Ⅰ、Ⅱ和Ⅲ型的重组型,与已有型别比较,不但有不同的位点图谱,且有多个点突变。