Identification of prognostic biomarkers for cholangiocarcinoma by combined analysis of molecular characteristics of clinical MVI subtypes and molecular subtypes.

Cholangiocarcinoma (CCA) is widely noted for its high degree of malignancy, rapid progression, and limited therapeutic options. This study was carried out on transcriptome data of 417 CCA samples from different anatomical locations. The effects of lipid metabolism related genes and immune related genes as CCA classifiers were compared. Key genes were derived from MVI subtypes and better molecular subtypes. Pathways such as epithelial mesenchymal transition (EMT) and cell cycle were significantly activated in MVI-positive group. CCA patients were classified into three (four) subtypes based on lipid metabolism (immune) related genes, with better prognosis observed in lipid metabolism-C1, immune-C2, and immune-C4. IPTW analysis found that the prognosis of lipid metabolism-C1 was significantly better than that of lipid metabolism-C2 + C3 before and after correction. KRT16 was finally selected as the key gene. And knockdown of KRT16 inhibited proliferation, migration and invasion of CCA cells.

First Report of Seedling Stem Rot on Jinxianlian (Anoectochilus roxburghii) Caused by Fusarium oxysporum in China.

Anoectochilus roxburghii is an important Chinese herbal medicine plant belonging to Orchidaceae and known as Jinxianlian. This orchid is cultivated and mostly adopted to treat diabetes and hepatitis. About 2 billion artificially cultivated seedlings of Jinxianlian are required each year and approximately $600 million in fresh A. roxburghii seedlings is produced in China. From 2011, sporadic occurrence of stem rot on Jinxianlian have been observed in greenhouses in Jinhua City (N29°05', E119°38'), Zhejiang Province. In 2018, nearly 30% of seedlings of Jinxianlian grown in greenhouse conditions were affected by stem rot in Jinhua City. Symptoms initially occurred in the stem at the soil line causing dark discoloration lesions, rotted tissues, wilting, and eventually leading to the death of the plants. A total of 23 diseased seedlings collected from seven different greenhouses were surface sterilized with 1.5% sodium hypochlorite for 3 min, then rinsed in water. Pieces of tissues disinfected from each sample were plated on 2% potato dextrose agar (PDA), and incubated at 25°C in the dark for 5 days (Kirk et al. 2008). A total of 19 isolates were recovered. They developed colonies with purple mycelia and beige or orange colors after 7 days of incubation under 25°C on PDA and carnation leaf agar (CLA) media (Kirk et al. 2008; Zhang et al. 2016). Colonies on PDA had an average radial growth rate of 3.1 to 4.0 mm /d at 25°C. Colony surface was pale vinaceous, floccose with abundant aerial mycelium. On CLA, aerial mycelium was sparse with abundant bright orange sporodochia forming on the carnation leaves. Microconidia were hyaline and oval-ellipsoid to cylindrical (3.7 to 9.3 × 1.3 to 2.9 µm) (n=19). Macroconidia were 3 to 5 septate and fusoid-subulate with a pedicellate base (27.4 to 35.6 × 3.2 to 4.2 µm) (n=19). These morphological features were consistent with Fusarium oxysporum (Sun et al. 2008; Lombard et al., 2019). To confirm the identification based on these morphological features, the internal transcribed spacer region (ITS) and translation elongation factor1 (TEF) were amplified from the DNA of 3 out of 19 isolates chosen at random respectively using the set primer ITS1/ITS4 and EF1/ EF2 (Sun, S., et al. 2018; Lombard et al., 2019). BLAST analysis revealed that the ITS sequences (OK147619, OK147620, OK147621) had 99% identity to that of F. oxysporum isolate JJF2 (GenBank MN626452) and TEF sequence (OK155999, OK156000, OK156001) had 100% identity to that of F. oxysporum isolate gss100 (GenBank MH341210). A multilocus phylogenetic analysis by Bayesian inference (BI) and maximum likelihood (ML) trees based on ITS and TEF indicated that the pathogen grouped consistently with F. oxysporum. Three out of 19 isolates chosen at random were selected to evaluate pathogenicity. Uninfected healthy A. roxburghii seedlings about 40 day-old planted in sterilized substrates were sprayed with distilled water containing 2 x 106 conidia per ml suspensions as inoculums, and plants sprayed with distilled water alone served as controls. Plants were then incubated at 25°C and 85% relative humidity. Ten plants were inoculated for each isolate. After 10 days, all plants inoculated developed stem rot symptoms, while control plants remained healthy. Cultures of Fusarium spp. were re-isolated only from inoculated plants with the frequency of 100% and re-identified by morphological characteristics as F. oxysporum, fulfilling Koch's postulates. To the best of our knowledge, this is the first report of F. oxysporum causing stem rot on A. roxburghii seedlings. As F. oxysporum is a devastating pathogenic fungus with a broad host range, measures should be taken in advance to manage stem rot of A. roxburghii.

[Preliminary study on memory function of Sorbus aucuparia suspension cell to biotic stress].

Plants have a memory function for the environmental stress they have suffered. When they are subjected to repeated environmental stress, they can quickly and better activate the response and adaptation mechanism to environmental stress, thus realizing long-term stable reproduction. However, most of the relevant studies are applied to crops and Arabidopsis thaliana rather than medicinal plants about the improvement of plant growth status and the effect on phytoalexin biosynthesis. In this study, yeast extract(YE) was used as an elicitor to simulate biotic stress, and the changes in biomass and the content of some secondary metabolites were measured by giving repeated stresses to Sorbus aucuparia suspension cell(SASC). The results showed that the accumulation levels of biomass and some secondary metabolites in SASC subjected to repeated stress are significantly increased at some time points compared with single stress. A phenomenon that SASC can memorize biotic stress is confirmed in this study and influences phytoalexin accumulation in SASC. Furthermore, the work laid the groundwork for research into the transgenerational stress memory mechanism of medicinal plant.

[Jasmonate signal pathway involved in phytoalexin biosynthesis in Sorbus aucuparia cell elicited by Hpa1].

The Harpin protein Hpa1 can induce defense responses in plant. This study aimed at investigating the role of jasmonate (JA) signal pathway in the process of biosynthesis of secondary metabolite in Sorbus aucuparia cell eliciting by Hpa1 crude extract (Hpa1 CE). The results showed that Hpa1 crude extract (Hpa1 CE) could induce phytoalexin synthesis in S. aucuparia cell， most of which was noraucuparin and its glycosides. Meanwhile Hpa1 CE treatment resulted in methyl jasmonate (MeJA) production increased and noraucuparin was de novo synthesized in large quantities. Combination of Hpa1 CE and salicylhydroxamic acid (SHAM, JA signaling inhibitor) caused the decreased MeJA and noraucuparin in the S. aucuparia cell compared with that in Hpa1 CE group. Real-time PCR results indicated that Hpa1 CE treatment caused down-regulation of JAZ and up-regulation of mcy2 in transcription level. Therefore Hpa1 CE elicited defense mechanism and JA signaling pathway involved in phytoalexin biosynthesis in S. aucuparia cell. It presented information to elucidate the role of JA signal pathway in stress response in the perspective of secondary metabolism of plant.

[Assessment of soil fertility for cultivation of Chinese herbal medicines].

The soil fertility has great impacts on the yielding of Chinese medicinal materials, as well as the generation of major components. The practices showed that soil fertility has been decayed with the growth of cultivation years,which is leading to adverse effect on quality and quantity of Chinese medicinal materials. However, there was a lack of domestic unified standard for assessment of soil fertility of Chinese medicinal material cultivation, which has seriously limited the soil management and quality control. In this text, we reviewed the progress on research of soil fertility evaluation, built the soil fertility evaluation index including soil texture,soil bulk density,soil organic matter,soil acidity and alkalinity,soil available nitrogen,soil available phosphorus, soil available potassium,soil animals and soil microorganisms. It would provide the direction and thought for standard-settin on soil fertility evaluation of Chinese medicinal material cultivation.

Proton-Pump Inhibitor Exposure Aggravates Clostridium difficile-Associated Colitis: Evidence From a Mouse Model.

BACKGROUND: Clostridium difficile is currently the leading cause of infectious diarrhea in hospitalized patients. In addition to the infection due to toxigenic C. difficile in the gastrointestinal tract of susceptible hosts, other predisposing factors for C. difficile infection (CDI) are identified, including advanced age, a prolonged hospital stay, and use of acid-suppressive drugs. Of note, exposure to gastric acid-reducing agents, such as H2 blockers and proton pump inhibitors (PPIs), remains a controversial risk factor, and has been associated with CDI in some studies but not in others. A mouse model of antibiotic-associated clostridial colitis was established to examine the role of PPIs for CDI. MATERIALS AND METHODS: A mouse model of antibiotic-associated clostridial colitis was set up. NF-κB reporter mice were used to address the in vivo spatial and temporal inflammatory patterns of C. difficile-associated colitis. Serum levels of lipopolysaccharide and dextran-FITC were measured to reflect the barrier permeability of affected intestines. RESULTS: Mice with CDI that were exposed to PPI exhibited greater losses of stool consistency and body and cecal weights than those that were not exposed to PPI. Further, more neutrophilic infiltrations, epithelial damage, and inflammatory cytokine expression were noted in colon specimens of the mice with PPI exposure. More-evident inflammatory responses were detected by in vivo imaging of NF-κB reporter mice with CDI that were exposed to PPI. Gut barrier permeability was increased to a greater extent, as reflected by higher serum levels of lipopolysaccharide and dextran-FITC in mice with CDI that were exposed to PPI. CONCLUSIONS: Our mouse model demonstrates that PPI exposure increases the severity of intestinal inflammation in mice with C. difficile-associated colitis.

Astragalus membranaceus modulates Th1/2 immune balance and activates PPARγ in a murine asthma model.

Astragalus membranaceus, a traditional Chinese herb, has been used to improve airway inflammation and asthma. The present study investigated whether A. membranaceus has immunotherapeutic effects on asthma, a chronic inflammatory mucosal disease that is associated with excess production of IgE, eosinophilia, T helper 2 (Th2) cytokines, and bronchial hyperresponsiveness. An ovalbumin (OVA)-induced, chronic inflammatory airway murine asthma model was used to examine the status of pulmonary inflammation after the administration of A. membranaceus. The IgE levels in serum and bronchoalveolar lavage fluid showed a tendency to decrease after the administration of A. membranaceus. The number of eosinophils decreased and infiltration of inflammatory cells and collagen deposition declined in lung sections after A. membranaceus administration. The RNA and protein levels of Th2 cytokines and the ratio of the GATA3/T-bet mRNA levels decreased after A. membranaceus treatment. Furthermore, the mRNA level of peroxisome proliferator-activated receptor γ (PPARγ), a nuclear hormone receptor, increased in the lung tissues of A. membranaceus-treated mice. Finally, an A. membranaceus water extract activated PPARγ activity in either human embryonic kidney 293 (HEK293) or A549 cells in a PPARγ-responsive element-containing luciferase reporter assay. These results indicate that A. membranaceus has an inhibitory effect on airway inflammation in a murine model of asthma through modulating the imbalanced relationship between Th1 and Th2 cytokines.

[A phenomenological study of the shift change experiences of clinical nurses in Taiwan].

BACKGROUND: The process of changing shifts requires that clinical nurses engage in critical communication and interaction activities. Little research has examined the shift-change phenomenon. How Taiwanese nurses interpret their lived shift-change experiences deserves further exploration. PURPOSE: This study explores the meaning of the shift-change experiences of nurses in Taiwan. METHODS: A hermeneutic phenomenological design was used. Data from interviews, participant observations, and field notes were analyzed. Twenty-six nurses with shift-change experience volunteered in a snowball sampling process. Data were collected using in-depth interviews. Hermeneutical analysis was used to explain the meaning of the nursing shift-change experience. RESULTS: The shift-change experiences of participants revealed their existential meaning and struggles toward self-transformation, adaptation, and self-settlement for survival. The meaning of the shift-change experience of clinical nurses in Taiwan are characterized by three themes: (a) 'A relay for accomplishing collective nursing goals', (b) 'An associated duties to be carried out jointly', and (c) 'An experience transmission as well as power practice'. CONCLUSIONS / IMPLICATIONS FOR PRACTICE: Our study highlights the cultural implications and existential meaning of the clinical shift change experience to nurses in hospitals in Taiwan. These findings provide a better understanding of the nursing shift-change experience in terms of both practical issues and nurses' perceptions. Findings may be used to improve in-service training programs and to suggest solutions to problems encountered during the shift-change period.

Laparoscopic spleen-preserving distal pancreatectomy with or without splenic vessel conservation: a retrospective study of 20 cases.

BACKGROUND/AIMS: To compare the outcomes and potential morbidities of laparoscopic spleen-preserving distal pancreatectomy with or without splenic vessel preservation in patients with benign or low-grade malignant pancreatic lesions. METHODOLOGY: Twenty patients who underwent spleen-preserving distal pancreatectomy were retrospectively analyzed. All the patients had benign or low-grade malignant pancreatic lesions that had not invaded the spleen. Twelve patients underwent Kimura's procedure and eight patients underwent Warshaw's. Perioperative data, and procedure-specific complications were compared between the two groups. RESULTS: Age, gender, and body mass index were comparable between the two groups. Operative time and intraoperative blood loss were significantly lower for patients who underwent Warshaw's procedure than for those who received Kimura's (p <0.05 for both). There were no significant differences between the two groups with regard to perioperative blood transfusions, length of postoperative hospital stays, or complication rates. Splenic infarction and gastric varices developed only in patients who underwent Warshaw's procedure (one case each). CONCLUSIONS: Our results suggest that the Kimura technique should be the first choice for patients with benign or low-grade malignant pancreatic lesions. Warshaw's technique was associated with a higher incidence of several complications. However, Warshaw's can increase the success rate of splenic preservation in some cases.

Metabolic-related gene signatures for survival prediction and immune cell subtypes associated with prognosis in intrahepatic cholangiocarcinoma.

OBJECTIVES: Our study aimed to reveal the metabolic-related gene signatures for survival prediction and immune cell subtypes associated with IHCC prognosis. METHODS: Differentially expressed metabolic genes were identified between survival group and dead group which were divided according to survival at discharge. Recursive feature elimination (RFE) and randomForest (RF) algorithms were applied to optimize the combination of feature metabolic genes, which were used to generate SVM classifier. Performance of SVM classifier was evaluated by receiver operating characteristic (ROC) curves. Gene set enrichment analysis (GSEA) was conducted to uncover the activated pathways in high risk group, and differences in immune cell distributions were revealed. RESULTS: There were 143 differentially expressed metabolic gens. RFE and RF identified 21 overlapping differentially expressed metabolic genes, and the constructed SVM classifier had excellent accuracy in training and validation dataset. RS survival prediction model was consisted of 10 metabolic genes. RS model had reliable predictive capability in the training and validation dataset. GSEA revealed 15 significant KEGG pathways that were relatively activated in the high risk group. High risk group had obviously lower counts of B cell naive and T cell CD4+ memory resting, while higher counts of B cell plasma and macrophage M2. CONCLUSION: Prognostic prediction model of 10 metabolic genes could accurately predict the prognosis of IHCC patients.

Electrical Sympathetic Neuromodulation Protects Bone Marrow Niche and Drives Hematopoietic Regeneration during Chemotherapy.

The sympathetic nervous system (SNS) of the bone marrow regulates the regeneration and mobilization of hematopoietic stem cells. Chemotherapy can damage bone marrow SNS, which impairs hematopoietic regeneration and aggravates hematologic toxicities. This leads to long-term bone marrow niche damage and increases mortality in patients undergoing chemotherapy. Electrical neuromodulation has been used to improve functional recovery after peripheral nerve injury. This study demonstrates that electrical sympathetic neuromodulation (ESN) of bone marrow can protect the bone marrow niche from chemotherapy-induced injury. Using carboplatin-treated rats, the SNS via the sciatic nerve innervating the femoral marrow with the effective protocol for bone marrow sympathetic activation is electrically stimulated. ESN can mediate several hematopoietic stem cells maintenance factors and promote hematopoietic regeneration after chemotherapy. It also activates adrenergic signals and reduces the release of pro-inflammatory cytokines, particularly interleukin-1 ß, which contribute to chemotherapy-related nerve injury. Consequently, the severity of chemotherapy-related leukopenia, thrombocytopenia, and mortality can be reduced by ESN. As a result, in contrast to current drug-based treatment, such as granulocyte colony-stimulating factor, ESN can be a disruptive adjuvant treatment by protecting and modulating bone marrow function to reduce hematologic toxicity during chemotherapy.

Single-cell electric lysis on an electroosmotic-driven microfluidic chip with arrays of microwells.

Accurate analysis at the single-cell level has become a highly attractive tool for investigating cellular content. An electroosmotic-driven microfluidic chip with arrays of 30-µm-diameter microwells was developed for single-cell electric lysis in the present study. The cellular occupancy in the microwells when the applied voltage was 5 V (82.4%) was slightly higher than that at an applied voltage of 10 V (81.8%). When the applied voltage was increased to 15 V, the cellular occupancy in the microwells dropped to 64.3%. More than 50% of the occupied microwells contain individual cells. The results of electric lysis experiments at the single-cell level indicate that the cells were gradually lysed as the DC voltage of 30 V was applied; the cell was fully lysed after 25 s. Single-cell electric lysis was demonstrated in the proposed microfluidic chip, which is suitable for high-throughput cell lysis.

[A new method for purification and identification of hepatocellular carcinoma stem cell of SMMC-7721].

OBJECTIVE: To explore a new efficient purification method of hepatocellular carcinoma (HCC) stem cells and identify their features. METHODS: Human hepatocellular carcinoma cell line SMMC-7721 was cultured in sphere-culture system of polyhedra-treated dish and tumor stem cell specific medium. Upon the formation of cellular sphere, the cells were inoculated subcutaneously into immunocompromised mice and received the interventions of different concentrations of cisplatin. Then the drug-resistant cells were purified and re-cultured in TSC medium. Finally the stem cell markers and tumor stem cell markers were determined through real-time polymerase chain reaction (PCR), immunofluorescence method and flow cytometry. RESULTS: Through the double filter of TSC medium and cisplatin-resistance, SMMC-7721 stem cells could be grown in a suspended form and formed spheres in TSC medium. The stem cell markers (NANOG, OCT-4, SOX-2 and Notch) and tumor stem cell markers (CD24, 90.0%; CD133, 6.1%; CD90, 4.8%) were all over-expressed in purified cancer stem cells as compared with ordinary cells. And the over-expression of CD24 was the most obvious. CONCLUSIONS: The combination of in vitro cell culture with TSC medium, in vivo proliferation and cisplatin resistance test is a new efficient method of purifying hepatocellular carcinoma stem cells. Tumor stem cell with stem cell characteristics and an over-expression of CD24 may be cloned from SMMC-7721.

Panax notoginseng saponins prevent colitis-associated colorectal cancer via inhibition IDO1 mediated immune regulation.

Colorectal cancer (CRC) is the third most lethal cancer and leading cause of cancer mortality worldwide. A key driver of CRC development is colon inflammatory responses especially in patients with inflammatory bowl disease (IBD). It has been proved that Panax notoginseng saponins (PNS) have anti-inflammatory, anti-oxidant and anti-tumor effects. The chemopreventive and immunomodulatory functions of PNS on colitis-associated colorectal cancer (CAC) have not been evaluated.This present study was designed to study the potential protective effects of PNS on AOM/DSS-induced CAC mice to explore the possible mechanism of PNS against CAC. Our study showed that PNS significantly alleviated colitis severity and prevented the occurrence of CAC. Functional assays revealed that PNS relieved immunosuppression of Treg cells in the CAC microenvironment by inhibiting the expression of IDO1 mediated directly by signal transducer and activator of transcription 1 (STAT1) rather than phosphorylated STAT1. Ultimately, Rh1, one of the PNS metabolites, exhibited the best inhibitory effect on IDO1 enzyme activity. Our study showed that PNS exerted significant chemopreventive function and immunomodulatory properties on CAC. It could reduce macrophages accumulation and Treg cells differentiation to reshape the immune microenvironment of CAC. These findings provided a promising approach for CAC intervention.

Characterization of a wheat heme oxygenase-1 gene and its responses to different abiotic stresses.

In animals and recently in plants, heme oxygenase-1 (HO1) has been found to confer protection against a variety of oxidant-induced cell and tissue injuries. In this study, a wheat (Triticum aestivum) HO1 gene TaHO1 was cloned and sequenced. It encodes a polypeptide of 31.7 kD with a putative N-terminal plastid transit peptide. The amino acid sequence of TaHO1 was found to be 78% similar to that of maize HO1. Phylogenetic analysis revealed that TaHO1 clusters together with the HO1-like sequences in plants. The purified recombinant TaHO1 protein expressed in Escherichia coli was active in the conversion of heme to biliverdin IXa (BV), and showed that the V(max) was 8.8 U·mg(-1) protein with an apparent K(m) value for hemin of 3.04 µM. The optimum Tm and pH were 35 °C and 7.4, respectively. The result of subcellular localization of TaHO1 showed that the putative transit peptide was sufficient for green fluorescent protein (GFP) to localize in chloroplast and implied that TaHO1 gene product is at least localized in the chloroplast. Moreover, we found that TaHO1 mRNA could be differentially induced by the well-known nitric oxide (NO) donor sodium nitroprusside (SNP), gibberellin acid (GA), abscisic acid (ABA), hydrogen peroxide (H(2)O(2)) and NaCl treatments. Therefore, the results suggested that TaHO1 might play an important role in abiotic stress responses.

Undifferentiated embryonal sarcoma of the liver with epithelioid features in an adult patient: A case report.

INTRODUCTION: Undifferentiated embryonal sarcoma of the liver (UESL) is a rare form of liver malignancy, with most cases reported in the pediatric population. This disease is extremely uncommon in adults. Herein, we report the first case of UESL with epithelioid features in an adult patient. PATIENT CONCERNS: A 50-year-old man was admitted to our hospital due to epigastric pain. DIAGNOSIS AND INTERVENTIONS: Computed tomography and magnetic resonance imaging revealed a space-occupying lesion in the right lobe of the liver. A right hemihepatectomy was performed. Postoperative pathological and immunohistochemical examinations confirmed the diagnosis of UESL and features of epithelioid differentiation. OUTCOMES: The patient recovered well and refused adjuvant therapy. Unfortunately, the patient died of tumor recurrence 3 months after hospital discharge. CONCLUSION: UESL is a rare form of liver cancer, with most cases reported in the pediatric population. This case study highlights an extremely uncommon case of UESL with epithelioid features and a very poor prognosis. The findings suggest that complete intraoperative resection and postoperative adjuvant therapy should be considered to improve the prognosis of adult patients with UESL with epithelioid features.

Surface Epitaxial Nano-Topography Facilitates Biomineralization to Promote Osteogenic Differentiation and Osteogenesis.

Biomimetic modification of hydroxyapatite on a polymer surface is a potent strategy for activating biological functions in bone tissue engineering applications. However, the polymer surface is bioinert, and it is difficult to introduce a uniform calcium phosphate (CaP) layer. To overcome this limitation, we constructed a specific nano-topographical structure onto a poly(ε-caprolactone) substrate via surface-directed epitaxial crystallization. Formation of the CaP layer on the nano-topological surface was enhanced by 2.34-fold compared to that on a smooth surface. This effect was attributed to the abundant crystallization sites for CaP deposition because of the increased surface area and roughness. Bone marrow mesenchymal stromal cells (BMSCs) were used to examine the biological effect of biomineralized surfaces. We clearly demonstrated that BMSCs responded to surface biomineralization. Osteogenic differentiation and proliferation of BMSCs were significantly promoted on the biomineralized nano-topological surface. The expression of alkaline phosphatase and osteogenic-related genes as well as extracellular matrix mineralization was significantly enhanced. The proposed strategy shows potential for designing bone repair scaffolds.

Novel dibenzofuran and biphenyl phytoalexins from Sorbus pohuashanensis suspension cell and their antimicrobial activities.

Two novel sulfur-containing dibenzofurans, sorbusins A (1) and B (2), two unprecedented biphenyl glycosides, 2'-hydroxyaucuparin 2'-O-ɑ-L-rhamnoside (3) and noraucuparin 5-O-ɑ-L-rhamnoside (4), and four known analogues (5-8), were isolated from Sorbus pohuashanensis suspension cell induced by yeast extract. Their structures were elucidated based on spectroscopic analyses and quantum calculation of 13C NMR data. Structurally, compound 1 possessed a rare naturally occurring benzothiazole moiety and represents the first example of thiazole fused dibenzofuran. A plausible biosynthetic pathway for the sulfur-containing dibenzofurans is proposed. These dibenzofuran and biphenyl phytoalexins were evaluated for their antimicrobial activities against pathogenic fungi and drug-resistant bacteria. Compound 7 exhibited significant antibacterial activity against methicinllin-resistant Staphylococcus aureus with an MIC value of 3.13 µg/mL.

Streptococcal collagen-like surface protein 1 promotes adhesion to the respiratory epithelial cell.

BACKGROUND: Collagen-like surface proteins Scl1 and Scl2 on Streptococcus pyogenes contain contiguous Gly-X-X triplet amino acid motifs, the characteristic structure of human collagen. Although the potential role of Scl1 in adhesion has been studied, the conclusions may be affected by the use of different S. pyogenes strains and their carriages of various adhesins. To explore the bona fide nature of Scl1 in adherence to human epithelial cells without the potential interference of other streptococcal surface factors, we constructed a scl1 isogenic mutant from the Scl2-defective S. pyogenes strain and a Scl1-expressed Escherichia coli. RESULTS: Loss of Scl1 in a Scl2-defective S. pyogenes strain dramatically decreased the adhesion of bacteria to HEp-2 human epithelial cells. Expression of Scl1 on the surface of the heterologous bacteria E. coli significantly increased adhesion to HEp-2. The increase in adhesion was nullified when Scl1-expressed E. coli was pre-incubated with proteases or antibodies against recombinant Scl1 (rScl1) protein. Treatment of HEp-2 cells with rScl protein or pronase drastically reduced the binding capability of Scl1-expressed E. coli. These findings suggest that the adhesion is mediated through Scl1 on bacterial surface and protein receptor(s) on epithelial cells. Further blocking of potential integrins revealed significant contributions of α2 and ß1 integrins in Scl1-mediated binding to epithelial cells. CONCLUSIONS: Together, these results underscore the importance of Scl1 in the virulence of S. pyogenes and implicate Scl1 as an adhesin during pathogenesis of streptococcal infection.

Endoscopic Nasogallbladder Drainage Combined with Laparoscopic Surgery for Type I Mirizzi Syndrome with Acute Cholecystitis: A Case Series Report.

OBJECTIVE: To investigate the safety and feasibility of endoscopic nasogallbladder drainage (ENGBD) combined with laparoscopic surgery for Mirizzi syndrome type I with acute cholecystitis. METHODS: An analysis of 4 patients with type I Mirizzi syndrome with acute cholecystitis admitted to the First Hospital of Jilin University. RESULTS: The patients underwent ENGBD, and laparoscopic surgery was evaluated postoperatively. All four patients successfully recovered from this combined surgical approach. CONCLUSION: The combination of ENGBD and laparoscopic surgery is safe and feasible for the treatment of patients with type I Mirizzi syndrome accompanied by acute cholecystitis. This approach may reduce the traumatic stress on patients and is worthy of widespread implementation.