Dual targeting negative enrichment strategy for highly sensitive and purity detection of CTCs.

Circulating tumor cells (CTCs) have significant clinical value in early tumor detection, dynamic monitoring and immunotherapy. CTC detection stands out as a leading non-invasive approach for tumor diagnostics and therapeutics. However, the high heterogeneity of CTCs and the occurrence of epithelial-mesenchymal transition (EMT) during metastasis pose challenges to methods relying on EpCAM-positive enrichment. To address these limitations, a method based on negative enrichment of CTCs using specific leukocyte targets has been developed. In this study, aiming to overcome the low purity associated with immunomagnetic beads targeting solely the leukocyte common antigen CD45, we introduced CD66b-modified immunomagnetic beads. CD66b, a specific target for neutrophils with abundant residues, was chosen as a complementary approach. The process involved initial collection of nucleated cells from whole blood samples using density gradient centrifugation. Subsequently, magnetically labeled leukocytes were removed by magnetic field, enabling the capture of CTCs with higher sensitivity and purity while retaining their activity. Finally, we selected 20 clinical blood samples from patients with various cancers to validate the effectiveness of this strategy, providing a new generalized tool for the clinical detection of CTCs.

Cell-wall-anchored proteins affect invasive host colonization and biofilm formation in Staphylococcus aureus.

As a major human and animal pathogen, Staphylococcus aureus can attach to medical implants (abiotic surface) or host tissues (biotic surface), and further establish robust biofilms which enhances resistance and persistence to host immune system and antibiotics. Cell-wall-anchored proteins (CWAPs) covalently link to peptidoglycan, and largely facilitate the colonization of S. aureus on various surfaces (including adhesion and biofilm formation) and invasion into host cells (including adhesion, immune evasion, iron acquisition and biofilm formation). During biofilm formation, CWAPs function in adhesion, aggregation, collagen-like fiber network formation, and consortia formation. In this review, we firstly focus on the structural features of CWAPs, including their intracellular function and interactions with host cells, as well as the functions and ligand binding of CWAPs in different stages of S. aureus biofilm formation. Then, the roles of CWAPs in different biofilm processes with regards in development of therapeutic approaches are clarified, followed by the association between CWAPs genes and clonal lineages. By touching upon these aspects, we hope to provide comprehensive knowledge and clearer understanding on the CWAPs of S. aureus and their roles in biofilm formation, which may further aid in prevention and treatment infection and vaccine development.

Simultaneous cholecystectomy for asymptomatic gallstones during elective colorectal cancer surgery.

BACKGROUND: Asymptomatic gallstones are commonly detected using preoperative imaging in patients with colorectal cancer (CRC), but its management remains a topic of debate. METHODS: Clinicopathologic characteristics of patients who had asymptomatic gallstones presenting during the colorectal procedure were retrospectively reviewed. Medical records, including postoperative morbidity, mortality, and long-term gallstone-related diseases, were assessed. RESULTS: Of 134 patients with CRC having asymptomatic gallstones, 89 underwent elective colorectal surgery only (observation group), and 45 underwent elective colorectal surgery with simultaneous cholecystectomy (cholecystectomy group). After propensity score matching (PSM), the complications were similar in the 2 groups. During the follow-up period, biliary complications were noted in 11 patients (12.4%) in the observation group within 2 years after the initial CRC surgery, but no case was found in the cholecystectomy group. After PSM, the incidence of long-term biliary complications remained significantly higher in the observation group than in the cholecystectomy group (26.5% vs 0.0%; P < .01). Multivariable logistic regression analysis identified female gender, old age (≥65 years old), and small multiple gallstones as independent risk factors for the development of long-term gallstone-related diseases in patients from the observation group. CONCLUSION: Simultaneous prophylactic cholecystectomy during prepared, elective CRC surgery did not increase postoperative morbidity or mortality but decreased the risk of subsequent gallstone-related complications. Hence, simultaneous cholecystectomy might be a preferred therapeutic option for patients with CRC having asymptomatic gallstones in cases of elective surgery, especially for older patients (≥65 years old), female patients, and those with small multiple calculi.

Developmental toxicity and potential mechanisms exposed to polystyrene microplastics and polybrominated diphenyl ethers during early life stages of fat greenling (Hexagrammos otakii).

The occurrence of microplastics (MPs) in aquatic ecosystems and their ability to absorb hydrophobic pollutants, such as persistent organic pollutants (POPs), is currently a significant concern. MPs, which are the main breakdown product of plastics, have been frequently detected in the environment, posing serious threats to organisms' health. One particular pollutant, 2,2',4,4'-tetrabromodiphenyl ether (BDE-47), is a dominant congener of PBDEs and is highly toxic to organisms. However, there is limited knowledge regarding the exposure of marine fishes to PBDEs through MPs and their combined toxic effects. In this study, the embryo toxicity of Hexagrammos otakii was conducted to investigate the combined effects of MPs and BDE-47. The results showed that MPs and BDE-47 co-exposure had detrimental effects on embryonic development, such as reduced hatchability, increased mortality, decreased heart rate, and body malformation. Moreover, the combined toxicity of these substances appeared more pronounced harmful effects compared to exposure to BDE-47 alone. Histopathological examination revealed that co-exposure can cause greater damage to hatching glands and yolk. The enrichment of Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways included phagosome, metabolism of xenobiotics by cytochrome P450, TCA cycle, and Wnt signaling pathway, which are closely related to embryonic growth. BDE-47 and MPs may activate the Wnt signaling pathway to affect the normal development of embryos. Our results suggest that MPs and BDE-47 exposure may cause growth disorders in the early life stages of H.otakii, leading to abnormal embryonic development. All these results will contribute to the further study of the ecological risk assessment and toxicity of MPs and organic pollutant mixtures in marine fish.

Decoding the Effects of High Hydrostatic Pressure and High-Temperature Short-Time Sterilization on the Volatile Aroma Profile of Red Raspberry Juice.

The loss of distinctive aromas due to sterilization significantly hinders efforts to enhance the sensory quality of fruit and vegetable juices. This study aimed to elucidate the impacts of high-hydrostatic pressure (HHP) and high-temperature short-time (HTST) sterilization methods on the loss of C6 aldehyde aroma-active compounds in red raspberry juice. External standard quantification and quantitative descriptive analysis (QDA) revealed a notable decline in the levels of hexanal and (Z)-3-hexenal following the HHP and HTST treatments (p < 0.05), resulting in a marked attenuation of the grassy aroma characteristic of red raspberry juice. Furthermore, a comprehensive examination of the precursors, pivotal enzymes, intermediates, and downstream aromas within the fatty acid metabolism pathway in different raspberry juice samples indicated that the C6 aldehydes loss induced by HHP and HTST sterilizations was primarily ascribed to the competitive inhibition of ß-oxidation and the hindered enzymatic oxidation of fatty acids. These insights suggest that modifying sterilization protocols and enhancing enzymatic stability may help preserve the aroma integrity of raspberry juice. Our findings offer practical guidance for optimizing juice processing techniques to maintain flavor.

Circulating serum fibroblast growth factor 21 as risk and prognostic biomarker of retinal artery occlusion.

To evaluate the predictive and prognostic value of fibroblast growth factor 21 (FGF21) levels in retinal artery occlusion (RAO) patients. In this case-control study, serum FGF21 levels were detected by using the ELISA method. Multivariable logistic regression analyses were performed to evaluate the significance of FGF21 in assessing the risk of developing RAO and its impact on vision and concurrent ischemic stroke. Compared with control group, serum FGF21 levels were significantly higher (median [IQR] = 230.90[167.40,332.20] pg/ml) in RAO patients. Multivariate logistic regression analysis showed that elevated serum FGF21 levels were associated with a higher risk of RAO occurrence (P = 0.025, OR [95%CI] = 9.672 [2.573, 36.359]) after adjustment for multiple confounding factors. Higher serum FGF21 levels were negatively associated with visual acuity improvement (P = 0.029, OR [95%CI] = 0.466[0.235, 0.925]) and positively correlated with concurrent ischemic stroke (P = 0.04, OR [95% CI] = 1.944[1.029, 3.672]) in RAO patients. Elevated serum FGF21 levels could promote the development of RAO and indicate worse visual prognosis and increase the risk of concurrent ischemic stroke, which might help clinicians early diagnose and treat RAO patients.

Deep neural network for the prediction of KRAS, NRAS, and BRAF genotypes in left-sided colorectal cancer based on histopathologic images.

BACKGROUND: The KRAS, NRAS, and BRAF genotypes are critical for selecting targeted therapies for patients with metastatic colorectal cancer (mCRC). Here, we aimed to develop a deep learning model that utilizes pathologic whole-slide images (WSIs) to accurately predict the status of KRAS, NRAS, and BRAFV600E. METHODS: 129 patients with left-sided colon cancer and rectal cancer from the Third Affiliated Hospital of Sun Yat-sen University were assigned to the training and testing cohorts. Utilizing three convolutional neural networks (ResNet18, ResNet50, and Inception v3), we extracted 206 pathological features from H&E-stained WSIs, serving as the foundation for constructing specific pathological models. A clinical feature model was then developed, with carcinoembryonic antigen (CEA) identified through comprehensive multiple regression analysis as the key biomarker. Subsequently, these two models were combined to create a clinical-pathological integrated model, resulting in a total of three genetic prediction models. RESULT: 103 patients were evaluated in the training cohort (1782,302 image tiles), while the remaining 26 patients were enrolled in the testing cohort (489,481 image tiles). Compared with the clinical model and the pathology model, the combined model which incorporated CEA levels and pathological signatures, showed increased predictive ability, with an area under the curve (AUC) of 0.96 in the training and an AUC of 0.83 in the testing cohort, accompanied by a high positive predictive value (PPV 0.92). CONCLUSION: The combined model demonstrated a considerable ability to accurately predict the status of KRAS, NRAS, and BRAFV600E in patients with left-sided colorectal cancer, with potential application to assist doctors in developing targeted treatment strategies for mCRC patients, and effectively identifying mutations and eliminating the need for confirmatory genetic testing.

Modeling and optimization of triclosan biodegradation by the newly isolated Bacillus sp. DL4: kinetics and pathway speculation.

Triclosan is a widely used antibacterial agent and disinfectant, and its overuse endangered ecological safety and human health. Therefore, reducing residual TCS concentrations in the environment is an urgent issue. Bacillus sp. DL4, an aerobic bacterium with TCS biodegradability, was isolated from pharmaceutical wastewater samples. Response surface methodology (RSM) and artificial neural network (ANN) were carried out to optimize and verify the different condition variables, and the optimal growth conditions of strain DL4 were obtained (35 °C, initial pH 7.31, and 5% v/v). After 48 h of cultivation under the optimal conditions, the removal efficiency of strain DL4 on TCS was 95.89 ± 0.68%, which was consistent with the predicted values from RSM and ANN models. In addition, higher R2 value and lower MSE and ADD values indicated that the ANN model had a stronger predictive capability than the RSM model. Whole genome sequencing results showed that many functional genes were annotated in metabolic pathways related to TCS degradation (e.g., amino acid metabolism, xenobiotics biodegradation and metabolism, carbohydrate metabolism). Main intermediate metabolites were identified during the biodegradation process by liquid chromatography-mass spectrometry (LC-MS), and a possible pathway was hypothesized based on the metabolites. Overall, this study provides a theoretical foundation for the characterization and mechanism of TCS biodegradation in the environment by Bacillus sp. DL4.

Clinical application of multicolor scanning laser ophthalmology in diagnosis and grading of central retinal artery occlusion.

Purpose: To characterize features of central retinal artery occlusion (CRAO) using multicolor (MC) imaging and to assess the differences in CRAO grading between color fundus photography (CFP) and MC image qualitatively and quantitatively. Methods: We conducted a prospective, cross-sectional study in the Department of Ophthalmology of Renmin Hospital of Wuhan University. In total, 86 acute CRAO patients were included. Spectral-domain optical coherence tomography (SD-OCT), CFP, and MC examinations were taken at baseline. Based on the findings of these three examinations, CRAO was divided into three grades (incomplete, subtotal, and total). Based on OCT grading criteria, we qualitatively compared the ability of grading CRAO by CFP and MC. CRAO patient's visual acuity (VA) was obtained from the initial visit. The retinal thickness was measured by SD-OCT. Superficial capillary plexus (SCP) and deep capillary plexus (DCP) were obtained from optical coherence tomography angiography (OCTA) examinations. Quantitative data were compared across the three acute CRAO subgroups and against three examination findings. Results: MC image had significantly higher power of acute CRAO detection than CFP (P = 0.03). In the same group of CRAO patients, there was no significant difference in VA when comparing OCT with the MC grading system or with the CFP grading system (all P > 0.05). Significant differences in VA were found between the three CRAO subgroups only under MC grading (P = 0.016). In incomplete CRAO patients, significant differences were found in central fovea thickness (CFT) when comparing OCT with the CFP grading system (P = 0.019). In the same group of CRAO patients, there was no significant difference in retinal thickness when comparing OCT with the MC grading system (All P > 0.05). Significance differences in CFT (P < 0.001), innermost retinal layer (IMRL; P < 0.01), middle retinal layer (MRL; P < 0.001), and outer retinal layer (ORL; P = 0.021) were found between the three CRAO subgroups by MC grading. Vessel density of SCP showed a statistically increased as the severity of three CRAO subgroups (P = 0.03), whereas DCP did not have significant differences (P = 0.745). Comparisons were made between the OCT grading method and the MC and CFP grading methods; there is no significant difference in vessel density of SCP and DCP (All P > 0.05). Conclusion: The images obtained by MC are superior to those obtained by CFP in CRAO grading, retinal thickness, and vessel density measurement. MC imaging may be more capable of CRAO grading than OCT. We recommend MC imaging to determine CRAO severity to guide disease treatment and predict visual prognosis.

Encapsulation of roast beef flavor by soy protein isolate/chitosan complex Pickering emulsions to improve its releasing properties during the processing of plant-based meat analogues.

During the production of plant-based meat analogues (PBMA), a significant loss of flavor characteristic compounds in meat-flavor essences could be observed. Pickering emulsion-based encapsulation is an effective method to improve their stability. Therefore, a soy protein isolate (SPI)/chitosan (CS) complex Pickering emulsion was fabricated to encapsulate roast beef flavor (RBF) and further applied in the processing of PBMA. Our results indicated that the network structure of emulsions was dominated by elasticity, while hydrogen and covalent bonding interactions played important roles in the encapsulation process. The release rate of flavor compounds gradually increased with the increase of pH value, glutamine transaminase, NaCl content, heating temperature or heating time, while encapsulation significantly reduced the loss of characteristic aroma compounds. In addition, the releasing characteristics of aroma compounds and textural properties of PBMA were greatly improved by treating with RBF-loaded emulsions. Consequently, the emulsions were promising to improve the flavor quality of PBMA.

Plasmalogens and Octanoylcarnitine Serve as Early Warnings for Central Retinal Artery Occlusion.

Central retinal artery occlusion (CRAO) is a kind of ophthalmic emergency which may cause loss of functional visual acuity. However, the limited treatment options emphasize the significance of early disease prevention. Metabolomics has the potential to be a powerful tool for early identification of individuals at risk of CRAO. The aim of the study was to identify potential biomarkers for CRAO through a comprehensive analysis. We employed metabolomics analysis to compare venous blood samples from CRAO patients with cataract patients for the venous difference, as well as arterial and venous blood from CRAO patients for the arteriovenous difference. The analysis of metabolites showed that PC(P-18:0/22:6(4Z,7Z,10Z,13Z,16Z,19Z)), PC(P-18:0/20:4(5Z,8Z,11Z,14Z)) and octanoylcarnitine were strongly correlated with CRAO. We also used univariate logistic regression, random forest (RF), and support vector machine (SVM) to screen clinical parameters of patients and found that HDL-C and ApoA1 showed significant predictive efficacy in CRAO patients. We compared the predictive performance of the clinical parameter model with combined model. The prediction efficiency of the combined model was significantly better with area under the receiver operating characteristic curve (AUROC) of 0.815. Decision curve analysis (DCA) also exhibited a notably higher net benefit rate. These results underscored the potency of these three substances as robust predictors of CRAO occurrence.

Secretion of IFN-γ by specific T cells in HCMV infection.

One major risk for recipients undergoing allogeneic hematopoietic stem cell transplants (allo-HSCTs) is infection with the human cytomegalovirus (HCMV). For HCMV treatment, it is especially crucial to be able to differentiate between recipients who are at high risk of reactivation and those who are not. In this study, HCMV-DNA was collected from 60 HLA-A*02 allo-HSCT recipients before and after transplantation. After transplantation, the release of interferon (IFN)-γ by T cells specific to HCMV was assessed using the enzyme-linked immunospot assay (ELISPOT). The results show that the median viral load (VL) was significantly higher in the HCMV persistent-infection group compared to the non-persistent-infection group (p = 0.002), and that the late-infection rate was considerably higher in the high-VL group compared to the low-VL group (p = 0.014). The uninfected group had a considerably higher median IFN-γ spot-forming cell (SFC) count than the persistent-infection group (p = 0.001), and IFN-γ SFC counts correlated negatively and linearly with VLs (r = -0.397, p = 0.002). The immune-response groups showed significantly difference in median VL (p = 0.018), and the high immune response group had a reduced late-infection rate than the no/low immune response groups (p = 0.049). Our study showed that allo-HSCT recipients with a high VL at an early transplantation stage were at high risk for late HCMV infection. Further HCMV reactivation can be prevented by HCMV-specific T cells secreting enough IFN-γ.

A mRNA Vaccine for Crimean-Congo Hemorrhagic Fever Virus Expressing Non-Fusion GnGc Using NSm Linker Elicits Unexpected Immune Responses in Mice.

Crimean-Congo hemorrhagic fever (CCHF), caused by Crimean-Congo Hemorrhagic virus (CCHFV), is listed in the World Health Organization's list of priority diseases. The high fatality rate in humans, the widespread distribution of CCHFV, and the lack of approved specific vaccines are the primary concerns regarding this disease. We used microfluidic technology to optimize the mRNA vaccine delivery system and demonstrated that vaccination with nucleoside-modified CCHFV mRNA vaccines encoding GnNSmGc (vLMs), Gn (vLMn), or Gc (vLMc) induced different immune responses. We found that both T-cell and B-cell immune responses induced by vLMc were better than those induced by vLMn. Interestingly, immune responses were found to be lower for vLMs, which employed NSm to link Gn and Gc for non-fusion expression, compared to those for vLMc. In conclusion, our results indicated that NSm could be a factor that leads to decreased specific immune responses in the host and should be avoided in the development of CCHFV vaccine antigens.

LncRNA XXYLT1-AS2 promotes tumor progression via autophagy inhibition through ubiquitinated degradation of TFEB in hepatocellular carcinoma

Purpose There is compelling evidence that long-stranded non-coding RNAs (lncRNAs) play an important role in the progression of hepatocellular carcinoma (HCC). The aim of this study was to investigate the role of lncRNA XXYLT1 antisense-2 (XXYLT1-AS2) in HCC progression. Methods Real-time PCR was used to assess the levels of XXYLT1-AS2 in plasma from HCC and normal patients. Cell proliferation, apoptosis, migration, and invasion were monitored, and tumor xenografts were established to investigate the biological functions of XXYLT1-AS2 by gain-of-function and loss-of-function studies in vitro and in vivo, the expression of autophagy biomarkers and transcriptional factor EB (TFEB) was examined by immunoprecipitation, ubiquitination assays, and western blotting. Autophagy inhibitor, 3-methyladenine (3MA), and proteasome inhibitor, MG132, were used to verify the role of autophagy in HCC progression and the effect of XXYLT1-AS2 on TFEB ubiquitination, respectively. Results In this study, we identified that lncRNA XXYLT1-AS2 is highly expressed in HCC plasma and promotes tumor growth in vivo. In functional studies, it was found that silent expression of XXYLT1-AS2 inhibited HCC proliferation, migration, invasion, and activated autophagy of HCC cells, which were attenuated by autophagy inhibitor, 3MA. Mechanistically, XXYLT1-AS2 decreased the protein level of TFEB through promoting its degradation by ubiquitin proteasome pathway. Conclusion XXYLT1-AS2 plays an oncogenic role in HCC progression through inhibition of autophagy via promoting the degradation of TFEB, and thus could be a novel target for HCC treatment (AU)

The coming future: The role of the oral-microbiota-brain axis in aroma release and perception.

The field of aroma release and perception during the oral process has been well studied. However, the traditional approaches have not fully explored the integration of oral biology, microbiology, and neurology to further understand aroma release and perception mechanisms. Herein, to address the existing challenges in this field, we introduce the oral-microbiota-brain axis (OMBA), an innovative framework that encapsulates the interactive relationships among saliva and the oral mucosa, the oral microbiota, and the brain in aroma release and perception. This review introduces the OMBA and highlights its role as a key interface facilitating the sensory experience of aroma. Based on a comprehensive literature survey, the specific roles of the oral mucosa, oral microbiota, saliva, and brain in the OMBA are discussed. This integrated approach reveals the importance of each component and the interconnected relationships within this axis in the overall process of aroma release and perception. Saliva and the oral mucosa play fundamental roles in aroma release and perception; the oral microbiota regulates aroma release and impacts olfactory perception; and the brain's intricate neural circuitry is central to the decoding and interpretation of aroma signals. The components of this axis are interdependent, and imbalances can disrupt aroma perception. The OMBA framework not only enhances our comprehension of aroma release and perception but also paves the way for innovative applications that could heighten sensory experiences.

Mucous cell histopathology and label-free quantitative proteomic analysis of skin mucus in fat greenling (Hexagrammos otakii) infected with Vibrio harveyi.

Hexagrammos otakii is favored by consumers and aquaculture practitioners because of its strong adaptability and fast growth. However, recently, frequent outbreaks of diseases in the breeding of H. otakii have led to significant economic losses, especially due to bacterial diseases, which limit the healthy breeding of H. otakii. As a luminescent Gram-negative bacterium, Vibrio harveyi is the main pathogenic bacteria of H. otakii. In this study, the histopathology and label-free quantitative proteomics analysis were performed to reveal the changes of skin mucus proteins in H. otakii after infection with V. harveyi. The histopathological changes in the skin of H. otakii showed that when the bacteria were injected into the epithelial cells, it caused an increase in the number of mucous cells and a certain degree of damage and deformation in skin. Moreover, the quantitative proteomics analysis revealed a total of 364 differentially expressed proteins (DEPs), and these DEPs were found to be involved in environmental information processing, metabolism, infectious diseases: bacteria, replication and repair. More importantly, the enrichment analysis of the DEPs revealed that these different proteins were mainly targeted immune-related pathways. After infection of bacteria, the host's immune ability will be weakened, causing V. harveyi to enter the organism more easily, resulting in increased mucus in H. otakii, which will eventually lead to a decline in its physical function. These results provided an insight into a series of physiological changes after the bacterial infection of fish at the proteomic level and basic data for further exploration of the potential mechanism of skin mucus. Taken together, the results indicated more opportunities for the future designs and discoveries of effective antibacterial vaccines and antibacterial drugs for H. otakii.

Single-cell RNA sequencing highlights epithelial and microenvironmental heterogeneity in malignant progression of pancreatic ductal adenocarcinoma.

Intraductal papillary mucinous neoplasms (IPMNs) of the pancreas are bona fide precursor lesions of pancreatic ductal adenocarcinoma (PDAC). Single-cell transcriptomics provides a unique perspective for dissecting the epithelial and microenvironmental heterogeneity that accompanies progression from benign IPMNs to invasive PDAC. Single-cell RNA sequencing was performed through droplet-based sequencing on 35 693 cells from three high-grade IPMNs and two IPMN-derived PDACs (all surgically resected). Analysis of single-cell transcriptomes revealed heterogeneous alterations within the epithelium and the tumor microenvironment during the progression of noninvasive dysplasia to invasive cancer. For epithelial cells, we identified acinar-ductal cells and isthmus-pit cells enriched in IPMN lesions and profiled three types of PDAC-unique ductal cells. Notably, a proinflammatory immune component was distinctly observed in IPMNs, comprising CD4+ T cells, CD8+ T cells, and B cells, whereas M2 macrophages were significantly accumulated in PDAC. Through the analysis of cellular communication, the osteopontin gene (SPP1)-CD44 pathway between macrophages and epithelial cells were particularly strengthened in the PDAC group. Further prognostic analysis revealed that SPP1 is a biomarker of IPMN carcinogenesis for surveillance. This study demonstrates the ability to perform high-resolution profiling of single cellular transcriptomes during the progression of high-grade IPMNs to cancer. Notably, single-cell analysis provides an unparalleled insight into both epithelial and microenvironmental heterogeneity associated with early cancer pathogenesis and provides practical markers for surveillance and targets for cancer interception.

Severe tricuspid regurgitation with chordae tendinae rupture in CABG surgery.

A 58-year-old male patient was admitted with chest pain and was diagnosed with coronary heart disease. He was scheduled for coronary artery bypass grafting (CABG) under cardiopulmonary bypass (CPB). Intraoperative real-time transesophageal echocardiography (TEE) showed that the tricuspid valves were well-aligned and subtle regurgitation. Real-time TEE after separation from CPB showed severe tricuspid regurgitation and prolapsed chordae tendineae. The tricuspid chordae tendineae rupture due to a right atrial venous return cannula. The use of negative pressure to improve venous drainage during CPB may result in the tricuspid valve being adsorbed to the cannula, increasing the likelihood of injury to the tricuspid valve.

Enhanced Biofilm Formation by Tetracycline in a Staphylococcus aureus Naturally Lacking ica Operon and atl.

Staphylococcus aureus is a major, widespread pathogen, and its biofilm-forming characteristics make it even more difficult to eliminate by biocides. Tetracycline (TCY) is a major broad-spectrum antibiotic, the residues of which can cause deleterious health impacts, and subinhibitory concentrations of TCY have the potential to increase biofilm formation in S. aureus. In this study, we showed how the biofilm formation of S. aureus 123786 is enhanced in the presence of TCY at specific subinhibitory concentrations. S. aureus 123786 used in this study was identified as Staphylococcal Cassette Chromosome mec III, sequence type239 and naturally lacking ica operon and atl gene. Two assays were performed to quantify the formation of S. aureus biofilm. In the crystal violet (CV) assay, the absorbance values of biofilm stained with CV at optical density (OD)540 nm increased after 8 and 16 hr of incubation when the concentration of TCY was 1/2 minimum inhibitory concentration (MIC), whereas at the concentration of 1/16 MIC, the absorbance values increased after 16 and 24 hr of incubation. In tetrazolium salt reduction assay, the absorbance value at OD490 nm of S. aureus 123786 biofilms mixed with 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium solution increased after 8 hr when the concentration of TCY was 1/4 MIC, which may be correlated with the higher proliferation and maturation of biofilm. In conclusion, the biofilm formation of S. aureus 123786 could be enhanced in the presence of TCY at specific subinhibitory concentrations.