Sudden cardiac arrest and coexisting mitral valve prolapse: a case report and literature review

The aetiology of sudden cardiac arrest can often be identified to underlying cardiac pathology. Mitral valve prolapse is a relatively common valvular pathology with symptoms manifesting with increasing severity of mitral regurgitation (MR). It is unusual for severe MR to be present without symptoms, and there is growing evidence that this subset of patients may be at increased risk of sudden cardiac arrest or death. The difficulty lies in identifying those patients at risk and applying measures that are appropriate to halting progression to cardiac arrest. This article examines the association of mitral valve prolapse with cardiac arrests, the underlying pathophysiological process and the strategies for identifying those at risk

MEMS and NEMS - micro (and nano) electromechanical systems

MEMS and NEMS use and application is growing and their market is expanding. With the development of 5G and IoT technologies the number of MEMS components is always increasing.In this paper an introduction to MEMS/NEMS definition, categories, and advantages. Fabrication techniques of MEMS/NEMS are discussed. Finally, an elaborative analysis of the different applications of MEMS/NEMS, followed by a discussion of the future of Micro / Nano electromechanical Systems.</p

Clinical and laboratory studies of mesenchymal stem cells in long bone fracture nonunion

Treatment of atrophic long bone fracture nonunion is challenging with current therapeutic interventions including bone morphogenetic proteins (BM Ps) or autologous mesenchymal stem cells (MSCs). In this work it was hypothesised that, total MSC numbers and their responsiveness to BMPs in the nonunion setting were compromised, leading to poor healing. Additionally, the rationale for systemic injection of MSCs to repair bone is based on a contentious concept of their widespread circulation. To address the number and functional competence of iliac crest bone marrow MSCs in nonunion, this study employed colony forming unit fibroblast and osteoblast assays (CFU-F, CFU-O) and flow cytometry enumeration of the CD45lowCD271+ cell population, to compare nonunions (n=11) with united long bone fracture patients (n=11). Unexpectedly, total number of MSCs, was higher in nonunion; however their proliferative capacity, was lower. No response to BMP-7, assessed by CFU-F, CFU-O and calcium deposition assays, was found in both nonunion and union study groups. Possible mechanical translocation of MSCs into the venous circulation was investigated using matched antecubital venous blood from the upper limb (UL) and lower limb femoral venous blood (LL) samples from nonunion patients undergoing reaming with reamer irrigation aspiration (RIA) (n=12) and other non-reaming procedures (NR, n=12) with control groups including UL from early rheumatoid arthritis (RA, n=11) and healthy controls (n=12). CFU-F assay results revealed the presence of MSC colonies in LL at higher frequencies than UL samples in RIA and NR, (8LL, 2PB) and (SLL, 1 PB) respectively. None were detected in the UL of RA and controls. Altogether, these results indicate a functional defect in proliferative capacity of MSCs in nonunion. MSCs however are unlikely to circulate and contribute to reduced healing at fracture sites. This points towards a generalized systemic effect of the nonunion state on MSC dynamics, which should be further explored in future

Efficacy of Mesenchymal Stem Cells in Suppression of Hepatocarcinorigenesis in Rats: Possible Role of Wnt Signaling

<p>Abstract</p> <p>Background</p> <p>The present study was conducted to evaluate the tumor suppressive effects of bone marrow derived mesenchymal stem cells (MSCs) in an experimental hepatocellular carcinoma (HCC) model in rats and to investigate the possible role of Wnt signaling in hepato-carcinogenesis.</p> <p>Methods</p> <p>Ninety rats were included in the study and were divided equally into: Control group, rats which received MSCs only, rats which received MSCs vehicle only, HCC group induced by diethylnitroseamine (DENA) and CCl_<b>4</b>, rats which received MSCs after HCC induction, rats which received MSCs before HCC induction. Histopathological examination and gene expression of Wnt signaling target genes by real time, reverse transcription-polymerase chain reaction (RT-PCR) in rat liver tissue, in addition to serum levels of ALT, AST and alpha fetoprotein were performed in all groups.</p> <p>Results</p> <p>Histopathological examination of liver tissue from animals which received DENA-CCl₄only, revealed the presence of anaplastic carcinoma cells and macro-regenerative nodules type II with foci of large and small cell dysplasia. Administration of MSCs into rats after induction of experimental HCC improved the histopathological picture which showed minimal liver cell damage, reversible changes, areas of cell drop out filled with stem cells. Gene expression in rat liver tissue demonstrated that MSCs downregulated <it>β-catenin</it>, proliferating cell nuclear antigen (<it>PCNA</it>), <it>cyclin D </it>and <it>survivin </it>genes expression in liver tissues after HCC induction. Amelioration of the liver status after administration of MSCs has been inferred by the significant decrease of ALT, AST and Alpha fetoprotein serum levels. Administration of MSCs before HCC induction did not show any tumor suppressive or protective effect.</p> <p>Conclusions</p> <p>Administration of MSCs in chemically induced HCC has tumor suppressive effects as evidenced by down regulation of Wnt signaling target genes concerned with antiapoptosis, mitogenesis, cell proliferation and cell cycle regulation, with subsequent amelioration of liver histopathological picture and liver function.</p

Morphological examination of the accessory sex glands of the Barki bucks (Capra hircus)

The present investigation was prepared to describe the accessory sex glands of the Barki bucks grossly and by light microscopy. There are four sex glands: ampullary, vesicular, prostate, and bulbourethral. The ampullary gland is an enlargement of the terminal part of the ductus deferens, its glandular part has branched tubuloalveolar glands, and its secretory alveoli lined with a pseudo-stratified epithelium composed of cuboidal to columnar cells. The vesicular gland takes the appearance of a cluster of grapes and the left vesicular gland is enlarged and higher than the right one. The vesicular gland is a lobulated tubuloalveolar gland with wide intralobular space and the gland contain a secretory unit which lined by pseudo-stratified columnar epithelium, and the interlobular ductules lined by the stratified epithelium, while the interlobular duct lined by simple cuboidal epithelium moreover, the lining epithelium of secretory part consists of tall columnar cells. The prostate gland consists only of the disseminated part and is enclosed by a connective tissue capsule that was thin dorsally, thick laterally, and reduced in thickness ventrally. The prostatic acini are lined by simple cuboidal epithelium. The bulbourethral gland was similar in size to the walnut and surrounded by a capsule and there are interlobular connective tissue septa that divided the gland into lobes and lobules of different sizes. The bulbourethral gland contains secretory units lined by the tall simple columnar epithelium of mucous type with basely located nuclei and eosinophilic cytoplasm contain granular secretion. The gross and microscopic examination of the four accessory sex glands gave valuable information in the future pathology diagnosis of the accessory sex glands of the Barki bucks

Distribution pattern of antibiotic resistance genes in Escherichia coli isolated from colibacillosis cases in broiler farms of Egypt

Background and Aim: Multidrug resistance (MDR) of Escherichia coli has become an increasing concern in poultry farming worldwide. However, E. coli can accumulate resistance genes through gene transfer. The most problematic resistance mechanism in E. coli is the acquisition of genes encoding broad-spectrum β-lactamases, known as extended-spectrum β-lactamases, that confer resistance to broad-spectrum cephalosporins. Plasmid-mediated quinolone resistance genes (conferring resistance to quinolones) and mcr-1 genes (conferring resistance to colistin) also contribute to antimicrobial resistance. This study aimed to investigate the prevalence of antimicrobial susceptibility and to detect β-lactamase and colistin resistance genes of E. coli isolated from broiler farms in Egypt. Materials and Methods: Samples from 938 broiler farms were bacteriologically examined for E. coli isolation. The antimicrobial resistance profile was evaluated using disk diffusion, and several resistance genes were investigated through polymerase chain reaction amplification. Results: Escherichia coli was isolated and identified from 675/938 farms (72%) from the pooled internal organs (liver, heart, lung, spleen, and yolk) of broilers. Escherichia coli isolates from the most recent 3 years (2018–2020) were serotyped into 13 serotypes; the most prevalent serotype was O125 (n = 8). The highest phenotypic antibiotic resistance profiles during this period were against ampicillin, penicillin, tetracycline, and nalidixic acid. Escherichia coli was sensitive to clinically relevant antibiotics. Twenty-eight selected isolates from the most recent 3 years (2018–2020) were found to have MDR, where the prevalence of the antibiotic resistance genes ctx, tem, and shv was 46% and that of mcr-1 was 64%. Integrons were found in 93% of the isolates. Conclusion: The study showed a high prevalence of E. coli infection in broiler farms associated with MDR, which has a high public health significance because of its zoonotic relevance. These results strengthen the application of continuous surveillance programs

Speciation of common Gram-negative pathogens using a highly multiplexed high resolution melt curve assay

The identification of the bacterial species responsible for an infection remains an important step for the selection of antimicrobial therapy. Gram-negative bacteria are an important source of hospital and community acquired infections and frequently antimicrobial resistant. Speciation of bacteria is typically carried out by biochemical profiling of organisms isolated from clinical specimens, which is time consuming and delays the initiation of tailored treatment. Whilst molecular methods such as PCR have been used, they often struggle with the challenge of detecting and discriminating a wide range of targets. High resolution melt analysis is an end-point qPCR detection method that provides greater multiplexing capability than probe based methods. Here we report the design of a high resolution melt analysis assay for the identification of six common Gram-negative pathogens; Escherichia coli, Klebsiella pneumoniae, Klebsiella oxytoca, Pseudomonas aeruginosa, Salmonella Sp, and Acinetobacter baumannii, and a generic Gram-negative specific 16S rRNA control. The assay was evaluated using a well characterised collection of 113 clinically isolated Gram-negative bacteria. The agreement between the HRM assay and the reference test of PCR and sequencing was 98.2% (Kappa 0.96); the overall sensitivity and specificity of the assay was 97.1% (95% CI: 90.1–99.7%) and 100% (95% CI: 91.78–100%) respectively