Prevalence of S. aureus and/or MRSA in hospitalized patients with diabetic foot and establishment of LAMP methods for rapid detection of the SCCmec gene.

BACKGROUND: Patients with diabetic feet are prone to be infected due to the impaired immune system. However, the prognostic outcome of different microbial infections remains controversial. Identification and rapid screening of the pathogenic microorganisms that pose the greatest threat to the prognosis of patients with diabetic foot infections (DFIs) is critical. METHODS: Clinical data were statistically analyzed, which were obtained from 522 patients with DFIs, including pathogenic bacterial culture results and treatment outcomes at the last return visit. In addition, a loop-mediated isothermal amplification (LAMP) detection method was developed to identify the prevalent subtype of methicillin-resistant Staphylococcus aureus (MRSA) in DFIs patients. This study was approved by the Ethics Committee of Nanfang Hospital (NFEC-202012-K6) and registered on ClinicalTrials.gov (NCT04916457) on June 1, 2021. RESULTS: We found that the proportion of patients with infections of Staphylococcus aureus (S. aureus) and MRSA was 27.7% (145/522) and 33.7% (49/145), respectively. Additionally, the incidence of osteomyelitis was 46.9% (23/49) and amputation/disability was 40.8% (20/49) in patients with MRSA infection, which were significantly higher compared to patients with other types of bacterial infections such as methicillin-susceptible Staphylococcus aureus (MSSA). Notably, we demonstrated that the main prevalent subtype of MRSA in DFIs patients in our hospital was Staphylococcal chromosomal cassettes mec (SCCmec) type II. In addition, it only takes 1.5 h to complete the entire experimental procedure in this LAMP assay, providing high sensitivity (100%) and specificity (77.8%) in hospitalized patients with DFIs. CONCLUSIONS: We demonstrated there is a very high rate of MRSA isolation in patients with DFIs and revealed that patients infected with MRSA are at a higher risk of developing osteomyelitis, and amputation or disability. Importantly, we have developed a method for quickly screening newly admitted patients for MRSA.

Seven bacterial response-related genes are biomarkers for colon cancer.

BACKGROUND: Colon cancer (CC) is a common tumor that causes significant harm to human health. Bacteria play a vital role in cancer biology, particularly the biology of CC. Genes related to bacterial response were seldom used to construct prognosis models. We constructed a bacterial response-related risk model based on three Molecular Signatures Database gene sets to explore new markers for predicting CC prognosis. METHODS: The Cancer Genome Atlas (TCGA) colon adenocarcinoma samples were used as the training set, and Gene Expression Omnibus (GEO) databases were used as the test set. Differentially expressed bacterial response-related genes were identified for prognostic gene selection. Univariate Cox regression analysis, least absolute shrinkage and selection operator-penalized Cox regression analysis, and multivariate Cox regression analysis were performed to construct a prognostic risk model. The individual diagnostic effects of genes in the prognostic model were also evaluated. Moreover, differentially expressed long noncoding RNAs (lncRNAs) were identified. Finally, the expression of these genes was validated using quantitative polymerase chain reaction (qPCR) in cell lines and tissues. RESULTS: A prognostic signature was constructed based on seven bacterial response genes: LGALS4, RORC, DDIT3, NSUN5, RBCK1, RGL2, and SERPINE1. Patients were assigned a risk score based on the prognostic model, and patients in the TCGA cohort with a high risk score had a poorer prognosis than those with a low risk score; a similar finding was observed in the GEO cohort. These seven prognostic model genes were also independent diagnostic factors. Finally, qPCR validated the differential expression of the seven model genes and two coexpressed lncRNAs (C6orf223 and SLC12A9-AS1) in 27 pairs of CC and normal tissues. Differential expression of LGALS4 and NSUN5 was also verified in cell lines (FHC, COLO320DM, SW480). CONCLUSIONS: We created a seven-gene bacterial response-related gene signature that can accurately predict the outcomes of patients with CC. This model can provide valuable insights for personalized treatment.

Multiplex lateral flow test strip for detection of carbapenemase genes using barcoded tetrahedral DNA capture probe-based biosensing interface.

Carbapenem-resistant Enterobacterales pose significant global health challenges due to their rapid spread and ability to hydrolyse various beta-lactam antibiotics. Rapid tests for these carbapenemase genes are crucial to ensure appropriate prescription administration and infection control. In this study, we developed a rapid visual nanodiagnostic platform for multiplexed detection of carbapenemase genes using a lateral flow strip. The nanodiagnostic strip was designed with separate barcoded DNA tetrahedrons for the blaKPC and blaNDM genes. These tetrahedrons were distributed on a nitrocellulose membrane at two different test lines as capture probes. When tested against a panel of carbapenemase genes, the tetrahedral probes captured single-stranded amplicons of asymmetric PCR via strand hybridisation. The amplicons acted as bridging elements, binding the DNA-modified gold nanoparticles to the test line of the strip, resulting in clear visual readouts specific to the blaKPC and blaNDM genes. By employing barcoded tetrahedrons and asymmetric PCR in conjunction with the lateral flow strip, a single diagnostic test enabled the detection of multiple carbapenemase genes. The test yielded results as low as 0.12 fM for blaKPC and 0.05 fM for blaNDM within 75 min. Furthermore, the strip effectively identified specific carbapenemase genes in clinical isolates using real-time PCR, antibody-based lateral flow systems for carbapenemase detection, and carbapenemase phenotype experiments. Thus, the strip develop has a high potential for testing blaKPC and blaNDM genes in practice.

The effect of plastic rearrangements on the flow of two-dimensional wet foam.

The effect of the elementary plastic events on the flow behavior of the two-dimensional wet foam is investigated by quasistatic simulation on the bubble scale. The position where the plastic event occurs is traced by recording the coordinate at which two bubbles separate in the simulation. A localized shear band is found, and the width of this band increases with the increase of foam quality. From the displacement fields of these bubbles, it shows that the T1 plastic events can give rise to an increase in local bubble displacements due to the separation between these bubbles. The average relative pressure as well as normal stress difference of bubbles increases with the flow of foam in the initial elastic domain and then decreases as the elastic domain turns into the plastic domain. In the plastic domain, the plastic events rearrange the local structure of foam, which leads to decreasing both the average pressure and the normal stress difference. Additionally, the wall slip of foam is discussed in the simulation as well. The width of the localized shear band is narrower under the slip boundary condition. Meanwhile, the plastic events occurring between the first and second layers of bubbles change the pulling force of the films near the wall and cause an instantaneous increase in the slip velocity.

Relationship between social isolation and glycaemic control of people previously diagnosed with diabetes: secondary analysis from the CHARLS.

OBJECTIVES: Social isolation may affect diabetes self-management. This study aimed to explore the relations between social isolation and glycaemic control in patients with diabetes and to explore lifestyle differences among individuals with different levels of social isolation. METHODS: The relevant data of 665 people previously diagnosed with diabetes included in the China Health and Retirement Longitudinal Study from 2011 to 2015 were extracted and analysed. The study included patient general information, blood glucose, lipids, glycosylated haemoglobin, social isolation index, health-related lifestyle factors and diabetes-related factors. Differences in metabolic abnormalities and modifiable lifestyles were compared among patients with varying levels of social isolation. RESULTS: Multiple linear regression analysis demonstrated that among men aged 45-64 years, the high social isolation group had significantly higher glycosylated haemoglobin levels compared with the low isolation group (7.29±1.81 vs 6.59±1.63, p=0.026). A positive correlation was observed between social isolation and blood glucose (ß=14.16; 95% CI 2.75 to 25.57; p=0.015) and glycosylated haemoglobin (ß=0.35; 95% CI 0.10 to 0.60; p=0.006), indicating that higher social isolation was associated with higher fasting blood glucose and glycosylated haemoglobin levels. However, no significant associations were observed in other age groups. Notably, men aged 45-65 years with high social isolation had higher depression rates (44.10% vs 24.60%, p=0.024), lower engagement in moderate exercise (5.70% vs 23.50%, p=0.019) and shorter 10-minute walks (17.10% vs 36.80%, p=0.027). Differences in other health-related and diabetes-related factors were not statistically significant. CONCLUSION: Middle-aged men with diabetes with higher social isolation tend to have higher blood glucose and glycosylated haemoglobin levels. This subset of patients requires targeted attention to provide social support from family and friends for improved glycaemic control. If necessary, education on diabetes should be made available to family members and friends.

Turmeric-Derived Nanoparticles Functionalized Aerogel Regulates Multicellular Networks to Promote Diabetic Wound Healing.

Regulation of excessive inflammation and impaired cell proliferation is crucial for healing diabetic wounds. Although plant-to-mammalian regulation offers effective approaches for chronic wound management, the development of a potent plant-based therapeutic presents challenges. This study aims to validate the efficacy of turmeric-derived nanoparticles (TDNPs) loaded with natural bioactive compounds. TDNPs can alleviate oxidative stress, promote fibroblast proliferation and migration, and reprogram macrophage polarization. Restoration of the fibroblast-macrophage communication network by TDNPs stimulates cellular regeneration, in turn enhancing diabetic wound healing. To address diabetic wound management, TDNPs are loaded in an ultralight-weight, high swelling ratio, breathable aerogel (AG) constructed with cellulose nanofibers and sodium alginate backbones to obtain TDNPs@AG (TAG). TAG features wound shape-customized accessibility, water-adaptable tissue adhesiveness, and capacity for sustained release of TDNPs, exhibiting outstanding performance in facilitating in vivo diabetic wound healing. This study highlights the potential of TDNPs in regenerative medicine and their applicability as a promising solution for wound healing in clinical settings.

l-thyroxine attenuates extracellular Hsp90α-induced vascular endothelial calcification in diabetes mellitus, as revealed by parallel metabolic profiles.

BACKGROUND AND AIMS: Diabetic atherosclerotic vascular disease is characterized by extensive vascular calcification. However, an elevated blood glucose level alone does not explain this pathogenesis. We investigated the metabolic markers underlying diabetic atherosclerosis and whether extracellular Hsp90α (eHsp90α) triggers vascular endothelial calcification in this particular metabolic environment. METHODS: A parallel human/animal model metabolomics approach was used. We analyzed 40 serum samples collected from 24 patients with atherosclerosis and from the STZ-induced ApoE-/- mouse model. A multivariate statistical analysis of the data was performed, and mouse aortic tissue was collected for the assessment of plaque formation. In vitro, the effects of eHsp90α on endothelial cell calcification were assessed by serum analysis, Western blotting and immunoelectron microscopy. RESULTS: Diabetic ApoE-/- mice showed more severe plaque lesions and calcification damage. Stearamide, oleamide, l-thyroxine, l-homocitrulline and l-citrulline are biomarkers of diabetic ASVD; l-thyroxine was downregulated in both groups, and the thyroid sensitivity index was correlated with serum Hsp90α concentration. In vitro studies showed that eHsp90α increased Runx2 expression in endothelial cells through the LRP1 receptor. l-thyroxine reduced the increase in Runx2 levels caused by eHsp90α and affected the distribution and expression of LRP1 through hydrogen bonding with glutamine at position 1054 in the extracellular segment of LRP1. CONCLUSIONS: This study provides a mechanistic link between characteristic serum metabolites and diabetic atherosclerosis and thus offers new insight into the role of extracellular Hsp90α in promoting vascular calcification.

Gram-Negative Bacteria and Lipopolysaccharides as Risk Factors for the Occurrence of Diabetic Foot.

CONTEXT: Imbalance of the skin microbial community could impair skin immune homeostasis and thus trigger skin lesions. Dysbiosis of skin microbiome may be involved in the early pathogenesis of diabetic foot (DF). However, the potential mechanism remains unclear. OBJECTIVE: To investigate the dynamic composition and function of the foot skin microbiome with risk stratification for DF and assess whether dysbiosis of the skin microbiome induces diabetic skin lesions. METHODS: We enrolled 90 consecutive subjects who were divided into 5 groups based on DF risk stratification: very low, low, moderate, and high risk for ulcers and a healthy control group. Integrated analysis of 16S ribosomal RNA and metagenomic sequencing of cotton swab samples was applied to identify the foot skin microbiome composition and functions in subjects. Then a mouse model of microbiota transplantation was used to evaluate the effects of the skin microbiome on diabetic skin lesions. RESULTS: The results demonstrated that, with the progression of diabetic complications, the proportion of gram-negative bacteria in plantar skin increased. At the species level, metagenome sequencing analyses showed Moraxella osloensis to be a representative core strain in the high-risk group. The major microbial metabolites affecting diabetic skin lesions were increased amino acid metabolites, and antibiotic resistance genes in microorganisms were abundant. Skin microbiota from high-risk patients induced more inflammatory cell infiltration, similar to the lipopolysaccharide (LPS)-stimulated response, which was inhibited by Toll-like receptor 4 (TLR4) antagonists. CONCLUSIONS: The skin microbiome in patients with diabetes undergoes dynamic changes at taxonomic and functional levels with the progression of diabetic complications. The increase in gram-negative bacteria on the skin surface through LPS-TLR4 signal transduction could induce inflammatory response in early diabetic skin lesions.

Research progress on the mechanism by which skin macrophage dysfunction mediates chronic inflammatory injury in diabetic skin.

Macrophages, the main immune cells in the skin, form an innate immune barrier. Under physiological conditions, skin maintains immune barrier function through macrophage phagocytosis and antigen presentation. Parenchymal and stromal cell regeneration plays an important role in skin injury repair and uses macrophage plasticity to influence and stabilize the skin microenvironment. Diabetic skin lesions are the most common diabetes complication and are involved in the early pathophysiology of diabetic foot. Therefore, studying the initial link in diabetic skin lesions is a research hot spot in the early pathogenesis of diabetic foot. Skin inflammation caused by hyperglycaemia, oxidative stress and other injuries is an important feature, but the specific mechanism is unknown. Recent studies have suggested that chronic inflammatory injury is widely involved in a variety of skin diseases, and whether it plays an important role in diabetic skin lesions is unclear. In this review, current research hotspots were combined with the pathogenesis of diabetic skin lesions and analysed from the perspectives of the physiological function of skin macrophages, the impairment of skin macrophages in diabetes, and the mechanism of chronic inflammatory injury in macrophages to provide a theoretical basis for early screening and evaluation of diabetic foot.

Rapid microbiological diagnosis based on 16S rRNA gene sequencing: A comparison of bacterial composition in diabetic foot infections and contralateral intact skin.

Diabetic foot infections (DFIs) represent a frequent complication of diabetes and a major cause of amputations. This study aimed to evaluate the utility of 16S rRNA gene sequencing for the rapid microbiological diagnosis of DFIs and to consistently characterize the microbiome of chronic diabetic foot ulcers (DFUs) and intact skin. Wound samples were collected by ulcer swabbing and tissue biopsy, and paired swabs of intact skin were collected from 10 patients with DFIs (five were moderately infected, and the other five were severely infected). Samples were analyzed by conventional culture and using Personal Genome Machine (PGM) 16S rRNA sequencing technology. The results showed that PGM technology detected significantly more bacterial genera (66.1 vs. 1.5 per wound sample, p < 0.001); more obligate anaerobes (52.5 vs. 0%, p < 0.001) and more polymicrobial infections (100.0 vs. 55.0%, p < 0.01) than conventional cultures. There was no statistically significant difference in bacterial richness, diversity or composition between the wound swabs and tissues (p > 0.05). The bacterial community on intact skin was significantly more diverse than that in DFUs (Chao1 value, p < 0.05; Shannon index value, p < 0.001). Gram-positive bacteria (67.6%) and aerobes (59.2%) were predominant in contralateral intact skin, while Gram-negative bacteria (63.3%) and obligate anaerobes (50.6%) were the most ubiquitous in DFUs. The most differentially abundant taxon in skin was Bacillales, while Bacteroidia was the bacterial taxon most representative of DFUs. Moreover, Fusobacterium (ρ = 0.80, p < 0.01) and Proteus (ρ = 0.78, p < 0.01) were significantly correlated with the duration of DFIs. In conclusion, PGM 16S rRNA sequencing technology could be a potentially useful technique for the rapid microbiological diagnosis of DFIs. Wound swabbing may be sufficient for sampling bacterial pathogens in DFIs compared with biopsy which is an invasive technique. The empirical use of broad-spectrum antibiotics covering Gram-negative obligate anaerobes should be considered for the treatment of moderate or severe DFIs.

Interferon alpha on expression of hTERT mRNA in peripheral blood mononuclear cells of patients with chronic hepatitis B.

Cell division is closely related to telomerase activity (hTERT mRNA). Lower expression of lymphocitic hTERT mRNA may easily cause cell aging, which is not beneficial to maintaining a durable lymphocyte division. To date, there is no study to investigate IFNα therapy on hTERT mRNA expression in PBMCs of patients with chronic hepatitis B (CHB). We quantitatively detected hTERT mRNA from study subjects and made each hTERT mRNA normalized (NhTERT mRNA). Mean NhTERT mRNA level was lower in either CHB group, but it significantly increased in IFNα-treated group compared with CHB control group, and a longer duration of IFNα therapy could increase the level. Moreover, the mean NhTERT mRNA in subgroup with HBeAg loss was significantly higher than that in subgroup without. NhTERT mRNA was markedly correlated with CD3(+) T lymphocyte count and CD4(+)/CD8(+) ratio. The results showed that IFNα therapy could upregulate the expression of hTERT mRNA in PBMCs.

The role of the microbiome in diabetes mellitus.

The microbiome is greatly significant for immune system development and homeostasis. Dysbiosis in gut microbial composition and function is linked to immune responses and the development of metabolic diseases, including diabetes mellitus (DM). However, skin microbiome changes in diabetic patients and their role in DM are poorly elucidated. In this review, we summarize recent findings about the association between the gut and skin microbiota and DM, highlighting their roles in the proinflammatory status of DM. Moreover, although there is evidence that the connection between the gut and skin causes the same activated innate immune response, additional studies are needed to explore the mechanism. These findings might inform future DM prevention, diagnosis and treatment.

Establishment and characterization of organoids from a patient with adenomyoepithelioma of the breast.

Adenomyoepithelioma (AME) of the breast is a rare tumor that is composed of proliferating epithelial and myoepithelial cells. The pathogenesis of AME remains unclear, and no breast cancer cells have been identified in such tumor tissues. In this study, we established patient-derived breast cancer organoids from the surgical tumor samples of an elderly Chinese woman with an AME of the breast. Our findings confirmed the successful establishment of organoids from an AME of the breast of this patient. A short tandem repeat analysis revealed that the DNA signature of the AME of the breast organoids matched the DNA signature of the original tumor specimen. Moreover, diameter assay confirmed that the organoids from the breast AME showed sensitivity to paclitaxel and doxorubicin treatments, which was similar to, but lesser than that of primary culture cells. In conclusion, we established an efficient 3-dimensional breast cancer organoid culture platform from an AME of the breast. This platform can be effectively used for exploring clinicopathological and genomic characteristics of AME of the breast to identify possible treatments and increase awareness about this disease entity.

Analysis of the Composition and Functions of the Microbiome in Diabetic Foot Osteomyelitis Based on 16S rRNA and Metagenome Sequencing Technology.

Metagenome sequencing has not been used in infected bone specimens. This prospective observational study explored the microbiome and its function in patients with diabetic foot osteomyelitis (DFO) and posttraumatic foot osteomyelitis (PFO) based on 16S rRNA sequencing and metagenome sequencing technologies. Spearman analysis was used to explore the correlation between dominant species and clinical indicators of patients with DFO. High-throughput sequencing showed that all the specimens were polymicrobial. The microbial diversity was significantly higher in the DFO group than in the PFO group. Firmicutes, Prevotellaceae, and Prevotella were the most abundant microbes in the DFO group. The most abundant microbes in the PFO group were Proteobacteria, Halomonadaceae, and Halomonas Prevotella denticola, Prevotella jejuni, and Prevotella fusca had positive correlation with the duration of diabetic foot infection (DFI_d). Proteus vulgaris was positively correlated with the infection index, while Bacteroides fragilis was negatively correlated. The microbial functional genes were more abundant in the DFO group than in the PFO group. Metagenome sequencing is feasible for the analysis of the microbiome in infected bone specimens. Gram-negative bacteria and anaerobes are dominant in DFO.

[Antibiotic susceptibility of pathogenic bacteria isolated from 893 children with lower respiratory infection in Guiyang].

OBJECTIVE: To investigate the distribution and the antibiotic susceptibility of pathogenic bacteria in children from Guiyang with lower respiratory infection (LRI). METHODS: The nasopharyngeal aspirate samples were obtained from 893 hospitalized children with LRI between August 2006 and June 2008. An antibiotic susceptibility test was performed using the VITEK system and the Kirby-Bauer diffuse method after bacteria were identified. RESULTS: Five hundred and forty-three patients (60.8%) were bacteria-positive. A total of 598 strains (30 kinds of bacteria) were obtained from the sputum samples. Of them, 533 strains (89.1%) were gram-negative and 57 were gram-positive (9.8%). Escherichia coli (E. coli) and Kleb-siella pneumoniae (K. pneumoniae) were common in gram-negative strains. They were susceptive to piperacillin/tazobactam, amikacin, ciprofloxacin, and levofloxacin, especially to imipenem. Streptococcus pneumoniae (S. pneumoniae) and Stapthylococcus aureus (S. aureus) were common in gram-positive strains. S. pneumoniae was susceptive to penicillin and cefazolin sodium, but S. aureus was resistant. Both were high susceptive to vancomycin, and resistant to roxithromycin. CONCLUSIONS: Gram-negative bacteria are the main pathogens in children from Guiyang with LRI, and E. coli and K. pneumoniae are common. The antibiotic susceptibility of pathogenic bacteria varies with different strains of bacteria. A reasonable selection of antibiotics should be based on the antibiotic susceptibility test.

Assessment and management of pain during dressing change in patients with diabetic foot ulcers: a best practice implementation project.

INTRODUCTION: Pain caused by dressing change has adverse effects on patients with a diabetic foot ulcer, including sleep disturbances, immobility, depression and anxiety. It is crucial that healthcare professionals use a standardized tool to assess and document pain during dressing change and then use this information to inform strategies to alleviate the pain. OBJECTIVES: The aim of this project was to implement evidence-based practice in assessment and management of pain during dressing change among patients with diabetic foot ulcers in an endocrinology unit in a tertiary hospital. METHODS: The JBI Practical Application of Clinical Evidence System (JBI PACES) and Getting Research into Practice (GRiP) audit and feedback tool were used for auditing clinical practice and translating evidence into practice. A baseline audit was performed to assess compliance with six criteria, followed by the implementation of evidence-based interventions to improve compliance. The follow-up audit using the same audit criteria was conducted to assess the effect of targeted strategies on compliance with best practice. RESULTS: The baseline audit revealed that compliance with evidence-based practice was low, with only one of the six audit criteria achieving a compliance rate above 60%. After brainstorming and synthesizing the literature, the project team identified barriers and strategies for implementing best practice. The follow-up audit showed improvements in compliance across all six criteria, although there was only a small improvement in one of the criteria. The compliance rate of the other five criteria improved to greater than 67%. CONCLUSION: A best practice implementation project that involved standardizing pain assessment and management, and delivering education materials to nursing staff and patients was completed using JBI PACES and GRiP. The project improved nurses' compliance with best practice. Nurses attach importance to relieving patients' pain when they perform wound care, while patients with a diabetic foot ulcer gain access to high-quality wound care. Future studies will be conducted to address new barriers that emerged during the follow-up audit.

DNA logic circuits based amplification system for quencher-free and highly sensitive detection of DNA and adenosine triphosphate.

We fabricated a quencher-free and enzyme-free fluorescence detection system by employing the DNA logic circuits as signal amplifier and 2-aminopurine as signal indicator, and applied it to detect DNA and adenosine triphosphate (ATP). The assay system consisted of three hairpin probes with a sequestered 2-aminopurine molecule in each stem domain which was defined as inputs A, B and C of the logic operation. These three hairpin inputs kept stability and coexisted in reaction solution without target. However, adding target to the system would break the stability and initiate a dynamic assembly of the three inputs through toehold mediated displacement, resulting in the formation of three way junction and the liberation of 2-aminopurine from duplex structure. The structural circumstance changes from duplex to single stand switched the signal from "off" to "on" due to the disarming of base stack interaction, thus attaining amplified fluorescence detection without any extra quencher and avoiding the limitation of distance-independent signal conversion in conventional methods. A limit of detection of 0.46 pM was achieved for target DNA with high discrimination capability. Moreover, the sensing system was expandable for ATP detection. Importantly, the method was simple and easy-to-operate. These features make the DNA logic circuits adaptable as an enzyme-free and quencher-free amplifier, and thus the proposed method offers a powerful platform for DNA and ATP determination, and even other biotargets in clinical diagnosis.

DNA Nanotweezers with Hydrolytic Activity for Enzyme-Free and Sensitive Detection of Fusion Gene via Logic Operation.

Gene fusion is a molecular event occurring in cellular proliferation and differentiation, and the occurrence of irregular fusion gene results in various malignant diseases. So, sensing fusion gene with high performance is an important task for integrating individual disease information. Here, we proposed a nonenzymatic and high-throughput fluorescent assay system for the detection of fusion gene by employing DNA nanotweezers with hydrolytic activity. This tweezer was assembled by three single-stranded DNAs and engineered with sensing elements and reporting subunits. In the absence of the fusion gene, the engineered tweezer remained opened and inactive which led to no signal output. However, the addition of fusion genes would cause structure alterations of the tweezer from open to close and further DNAzyme activation with the assembly of two reporting subunits. Then, the activated DNAzyme catalyzed fluorescence substrates for signal conversion. Taking BCR/ABL fusion gene as an example, the tweezer-based assay system showed not only excellent distinguishing capability towards different input targets but also high sensitivity with a detection limit of 5.29 pM. In addition to good detection performance, this system was simple and enzyme-free, offering a powerful nanometer tool as a smart nanodevice for sensing fusion detection.

[Pathogen analysis in patients with diabetic foot osteomyelitis using 16S rRNA high-throughput sequencing].

OBJECTIVE: To analyze the characteristics of pathogenic microorganisms in the infected bone tissues in patients with diabetic foot osteomyelitis (DFO) using 16S rRNA high-throughput sequencing to facilitate rapid and accurate detection of pathogens and effective infection control. METHODS: Between September, 2016 and April, 2017, 16 patients with DFO were admitted in our department and infected bone specimens were obtained during debridement. The pathogenic microorganisms in the specimens were identified using both 16S rRNA high-throughput sequencing and automatic blood culture analyzer, and the characteristics of the microflora were analyzed based on 16S rRNA sequencing data in comparison with the results of blood culture. RESULTS: The results of 16S rRNA sequencing showed that bone tissues of DFO contained diverse and uniformly distributed pathogenic organisms, among which 20 (87%) dominant genera were identified with Prevotella as the most abundant pathogen. Both 16S rRNA sequencing and routine culture results suggested the domination of gram-negative bacteria among the pathogens in DFO bone tissues. 16S rRNA sequencing, compared with routine culture, yielded a higher positivity rate (100% vs 88.24%) and detected a greater average number of pathogens (12.56 vs 1.50) and a higher proportion of gram-negative bacteria (67.16% vs 50.00%) in the samples. 16S rRNA sequencing detected nearly all the pathogens identified by routine culture except for Escherichia coli, Serratia marcescens and Enterobacter cloaca, and identified 13 genera that failed to be detected by routine culture, including the obligate or strict anaerobes Anaerococcus, Veillonella, Bacteroides, Fusobacterium, Porphyromonas, Finegoldia, Prevotella, Peptostreptococcus, Parvimonas, Peptoniphilus and Bulleidia. Routine culture did not detect any anaerobes in the samples but identified multidrug-resistant strains in as many as 58.33% of the pathogens. CONCLUSIONS: 16S rRNA high-throughput sequencing is capable of demonstrating the diversity and abundance of microflora in DFO bone tissues, where diverse and uniformly distributed pathogens can be detected with a discrete distribution of the dominant genera, most of which are gram-negative. Compared with routine culture method, 16S rRNA sequencing allows more convenient and accurate identification of the pathogens (especially gram-negative bacteria and anaerobes), and can be useful in clinical decision on appropriate treatment of DFO.

Drug resistance mutation profiles of the drug-naïve and first-line regimen-treated HIV-1-infected population of Suzhou, China.

Little is known about the prevalence of drug-resistant mutations in HIV-1-positive individuals in Suzhou, China. To elucidate the transmitted drug resistance (TDR) and acquired drug resistance mutation (ADR) profiles, we collected blood specimens from 127 drug-naïve and 117 first-line drug-treated HIV-1-infected individuals sampled from 2014 to 2016 in Suzhou. We successfully amplified pol fragments from 100 drug-naïve and 20 drug-treated samples. We then determined the drug-resistant mutations to protease (PR) and reverse-transcriptase (RT) inhibitors according to the Stanford drug resistance database. Overall, 11 and 13 individuals had transmitted (drug-naïve group) and acquired (treated group) resistance mutations, respectively. Six transmitted drug-resistant mutations were found, including two mutations (L33F and L76V) in the protease region and four (K70N/E and V179D/E) in the RT region. Only L76V was a major mutation, and K70N/E and V179D/E are known to cause low-level resistance to RT inhibitors. All 13 treated participants who had major drug resistance mutations demonstrated intermediate to high resistance to efavirenz and nevirapine, and six had a treatment duration of less than three months. No major mutations to RT inhibitors were found, implying that the epidemic of transmitted resistance mutations was not significant in this area. Our results suggest that more frequent virus load and drug resistance mutation tests should be conducted for individuals receiving antiretroviral treatment, especially for newly treated patients. Our research provides insights into the occurrence of HIV-1 drug resistance in Suzhou and will help to optimize the treatment strategy for this population.