[A case of repairing the destructive high-voltage electric burn wounds in the head, face, and neck based on the economic theory of flaps]

In September 8th, 2021, a male patient (aged 18 years) with severe destructive injuries of high-voltage electric burns in the head, face, and neck was admitted to General Hospital of Taiyuan Iron Steel (Group) Co., Ltd. Based on the economic theory of flaps, the flap donor site and transplantation method were optimized and evaluated before surgery, and then debridement of head, face, and neck wounds+removal of necrotic skull+free transplantation of super large latissimus dorsi myocutaneous flap+thin intermediate thickness skin graft transplantation from the left thigh was performed. The extra large flap donor site wound was sutured directly. This surgery reduced the adverse consequences of the flap donor site on the premise of ensure of repair effect. After operation, the patient's condition was stable, the flap and skin graft survived well, the repair effect of wound was well, the scar in the flap donor area was relatively mild, and the upper limb had no dysfunction.

Force-Loaded Cementocytes Regulate Osteoclastogenesis via S1P/S1PR1/Rac1 Axis

Orthodontically induced inflammatory root resorption (OIIRR) is the major iatrogenic complication of orthodontic treatment, seriously endangering tooth longevity and impairing masticatory function. Osteoclasts are thought to be the primary effector cells that initiate the pathological process of OIIRR; however, the cellular and molecular mechanisms responsible for OIIRR remain unclear. Our previous studies revealed that cementocytes, the major mechanically responsive cells in cementum, respond to compressive stress to activate and influence osteoclasts locally. For this study, we hypothesized that the sphingosine-1-phosphate (S1P) signaling pathway, a key mechanotransduction pathway in cementocytes, may regulate osteoclasts under the different magnitudes of either physiologic compressive stress that causes tooth movement or pathologic stress that causes OIIRR. Here, we show a biphasic effect of higher compression force stimulating the synthesis and secretion of S1P, whereas lower compression force reduced signaling in IDG-CM6 cementocytes. Using conditioned media from force-loaded cementocytes, we verified the cell-to-cell communication between cementocytes and osteoclasts and show that selective knockdown of S1PR1 and Rac1 plays a role in cementocyte-driven osteoclastogenesis via the S1P/S1PR1/Rac1 axis. Most importantly, the use of inhibitors of this axis reduced or prevented the pathological process of OIIRR. The intercellular communication mechanisms between cementocytes and osteoclasts may serve as a promising therapeutic target for OIIRR.

Meta-analysis of the diagnostic value of serum procalcitonin for burn sepsis in adults

OBJECTIVE

Serum procalcitonin (PCT) reflects the infection status of the organism and the severity of the infection. The purpose of this study was to systematically evaluate the diagnostic value of serum PCT for burn sepsis in adults and to provide a factual basis for future clinical diagnosis and decision-making.

MATERIALS AND METHODS

On August 16, 2022, six databases were searched in this study and a total of 856 studies were found. The retrieved literature was comprehensively evaluated according to the inclusion and exclusion criteria, and the valid data were extracted and included for analysis. The number of true positives, false positives, true negatives and false negatives were used as indicators to evaluate the diagnostic value of serum PCT for burn sepsis in adults.

RESULTS

In total, 15 studies met the inclusion criteria. Meta-analysis showed a combined sensitivity of 0.78 (95% CI: 0.69-0.84), a combined specificity of 0.85 (95% CI: 0.77-0.91), a combined positive likelihood ratio of 5.17 (95% CI: 3.25-8.25), a combined negative likelihood ratio of 0.26 (95% CI: 0.19-0.37), and a combined diagnostic ratio of 19.63 (95% CI: 10.17-37.90). The AUC was 0.88 (95% CI: 0.85-0.90).

CONCLUSIONS

Serum PCT provides good early diagnostic benefits for burn sepsis in adults. More high-quality studies are required to clarify its specific early diagnostic value.

Experimental Study and Mechanism Analysis of Preparation of α-Calcium Sulfate Hemihydrate from FGD Gypsum with Dynamic Method

Flue-gas desulphurization (FGD) gypsum is a highly prevalent industrial by-product worldwide, which can be an excellent alternative to natural gypsum due to its high content of CaSO₄·2H₂O. The preparation of α-calcium sulfate hemihydrate is a high-value pathway for the efficient use of FGD gypsum. Here, a dynamic method, or an improved autoclaved process, was used to produce α-calcium sulfate hemihydrate from FGD gypsum. In this process, the attachment water of the mixture of FGD gypsum and crystal modifiers was approximately 18%, and the pH value was approximately 6.0. The mixture did not need to be pressed into bricks or made into slurry, and it was directly sent into the autoclave reactor for reaction. It was successfully applied to the practical production and application of FGD gypsum, citric acid gypsum and phosphogypsum. In this work, the compositions and morphology of the product at different stages of the reaction were examined and compared. In particular, single-crystal diffraction was used to produce the crystal structure of CaSO₄·0.5H₂O, and the results were as follows: a = 13.550(3); b = 13.855(3); c = 12.658(3); β = 117.79(3)°; space group C2. The preferential growth along the c-axis and the interaction mechanism between the carboxylate groups and the crystal were discussed throughout the analysis of the crystal structure.

[Clinical effects of in situ perforation of preserved split scar matrix in combination with scalp transplantation and vacuum sealing drainage in the treatment of hypertrophic scar in non-functional sites after burns]

Objective: To investigate the clinical effects of in situ perforation of preserved split scar matrix in combination with scalp transplantation and vacuum sealing drainage in the treatment of hypertrophic scar in non-functional sites after burns. Methods: A retrospective observational study was used. From June 2017 to June 2019, 33 patients (24 males and 9 females, aged 8-50 years) who met the inclusion criteria with hypertrophic scars in non-functional sites outside the face after burns were treated in General Hospital of TISCO (the Sixth Hospital of Shanxi Medical University). All patients underwent scalp transplantation after perforation of retained split scar matrix in situ (with scar thinning area of 90-500 cm2), and then the vacuum sealing drainage was performed. The hematoma and infection of wounds were observed on the 7th day after operation. At the same time, the survival rate of skin grafting was observed and calculated. The flatness and thickness of the scar in the operative area were observed in 12 months after operation, and the itching and pain of the patients were recorded. Vancouver Scar Scale was used to score the scar of patients before operation and at 3, 6 and 12 months after operation. The healing time and hair growth of donor site were observed. Data were statistically analyzed with repeated analysis of variance, paired sample t test and bonferroni correction. Results: On the 7th day after operation, local subcutaneous hematoma appeared in the wound of 2 patients, which healed after dressing change; no infection occurred. On the 7th day after operation, the survival rate of skin grafting of patients was 94.6%-99.0%(96.8±1.2)%. Scar flatness was well, the thickness of scar was not significantly higher than that of normal skin in 12 months after operation, and the symptoms of itching pain of patients disappeared or significantly relieved. Vancouver Scar Scale scores of patients before operation and at 3, 6, and 12 months after operation were 12.1±2.8, 8.5±1.5, 7.6±1.6, 6.7±1.3, respectively, and the scores of 3, 6, and 12 months after operation were all significantly lower than that before operation (with t values of 4.48, 4.06, and 3.97, respectively, P<0.01). All the donor sites of the head healed well in 4-7 days after operation. By 3-6 months after operation, all patients had good hair growth in the donor site and achieved no scar healing. Conclusions: The treatment of hypertrophic scar in non-functional sites outside the face after burns by in situ perforation of preserved split scar matrix in combination with scalp transplantation and vacuum sealing drainage can effectively improve the appearance of hypertrophic scar in non-functional areas after burn and reduce its degree of hyperplasia, with scar-free donor site healing.

[Effects of psychological suggestion combined with rational food restriction therapy on blood glucose and lipid metabolism and mental resilience in patients with diabetes]

Objective: To analyze the effect of psychological suggestion combined with rational food restriction therapy on blood glucose, lipid metabolism and mental resilience in patients with diabetes. Methods: Patients with diabetes admitted to the Third Hospital of Nanchang from January 2020 to August 2020 were divided into the control group and the intervention group with randomized controlled and single blind methods. The control group was treated with routine dietary guidance and health education, and the intervention group was treated with psychological suggestion combined with rational diet therapy on the basis of the control group. Both groups were treated for 3 months. Blood glucose, lipid metabolism, mental resilience and quality of life were compared between the two groups at baseline and after 3-month intervention. Differences between groups and within groups were analyzed by t test and χ² test. Results: 100 patients in the control group and 81 patients in the intervention group completed 3-month intervention. After 3-month intervention, the levels of glycosylated hemoglobin, fasting blood glucose, 2-hour postprandial blood glucose, low-density lipoprotein cholesterol and triglyceride in both groups were lower than those before intervention. The levels of these indicators in intervention group were lower than those in control group (P<0.05). However, the levels of high-density lipoprotein cholesterol and the scores of tenacity, self-reliance, optimism, role function, emotional function, social function, physical function and cognitive function in both groups were higher than those before intervention. These indicators in intervention group were higher than those in control group (P<0.05). Conclusion: Psychological suggestion combined with rational food restriction therapy could effectively improve the glucose and lipid metabolism, mental resilience, and quality of life among patients with diabetes.

« BriserLaChaine.org » : conception d’un outil digital de contact tracing des personnes à risque d’infection au SARS-CoV-2 respectueux de la vie privée

Introduction

La pandémie de SARS-CoV-2 a entraîné en France un confinement généralisé à l’impact sanitaire, social et économique important. Sans traitement spécifique ni vaccin, il est primordial de pouvoir identifier et isoler les personnes infectées, ainsi que de retrouver et dépister les personnes contacts. Les outils digitaux de contact tracing sont intéressants mais entraînent des défis technologiques et éthiques. Bayes Impact, une association développant des outils digitaux à impact social a conçu en collaboration avec des médecins infectiologues la plateforme « BriserLaChaine.org » (BLC), de notification d’exposition au COVID-19.

Matériels et méthodes

Une plateforme web a été développée de mars à mai 2020 pour permettre d’identifier les cas suspects de COVID-19 et de calculer la période de contagiosité pour retrouver des personnes contacts en les prévenant par voie électronique. Un comité scientifique a conçu un outil d’orientation diagnostique en cas de symptômes par une veille bibliographique régulière et des avis d’experts.

Résultats

La plateforme BLC, ouverte à tous, ne nécessite ni téléchargement, ni compte, et ne stocke aucune donnée personnelle ou de géolocalisation. Soit l’infection par le COVID-19 est déjà connue et diagnostiquée par un médecin, soit suspectée par l’utilisateur devant la présence de symptômes. L’outil d’orientation diagnostique se base sur des points attribués selon chaque symptôme déclaré : 3 points pour une fièvre > 38 ° C, une toux ou une dyspnée ; 2 points pour asthénie, myalgies, expectorations, anosmie ou agueusie ; 1 point pour rhinorrhée, odynophagie, céphalée, diarrhée ou vomissements. Les personnes ayant une infection probable (score > 3 points) sont invitées à se faire tester et à consulter un médecin. Des conseils sont données aux autres, avec un lien vers le site maladiecoronavirus.com. La période de contagion considérée est de 2 jours avant et 13 jours après l’apparition des premiers symptômes. La notification des personnes contacts se fait soit par l’utilisateur soit anonymement via la plateforme. Depuis sa mise en ligne, il y a eu plus de 12 000 connexions.

Conclusion

La plateforme BLC est le premier outil digital de notification utilisable en France. Il ne collecte aucune donnée personnelle ni de géolocalisation. Sans adoption massive nécessaire, BLC peut être une aide en cas de recirculation du virus à l’échelle nationale de clusters, avec d’autres mesures de prévention. L’évaluation de l’adoption et de l’utilisation permettra de connaître l’adhésion en France de ce type d’outil et une modélisation d’impact est en cours de réalisation. À terme BLC a pour vocation à être étendu à d’autres pays.

Synthesis of bioinspired collagen/alginate/fibrin based hydrogels for soft tissue engineering

Hydrogels based on natural polymers offer a range of properties to mimic the native extracellular matrix, and provide microenvironments to preserve cellular function and encourage tissue formation. A tri-component hydrogel using collagen, alginate and fibrin (CAF) was developed and investigated at three collagen concentrations for application as a functional extracellular matrix analogue. Physical-chemical characterization of CAF hydrogels demonstrated a thermo-responsive crosslinking capacity at physiological conditions with stiffness similar to native soft tissues. CAF hydrogels were also assessed for cytocompatibility using L929 murine fibroblasts, pancreatic MIN6 β-cells and human mesenchymal stem cells (hMSCs); and demonstrated good cell viability, proliferation and metabolic activity after 7 days of in vitro culture. CAF hydrogels, especially with 2.5% w/v collagen, increased alkaline phosphatase production in hMSCs indicating potential for the promotion of osteogenic activity. Moreover, CAF hydrogels also increased metabolic activity of MIN6 β-cells and promoted the reconstitution of spherical pseudoislets with sizes ranging between 50 and 150 μm at day 7, demonstrating potential in diabetic therapeutic applications.

MicroRNA-340-5p modulates cisplatin resistance by targeting LPAATβ in osteosarcoma

MicroRNAs (miRNAs) play an important role in drug resistance and modulate the efficiency of chemotherapy. A recent study indicated that miR-340 functions as a tumor suppressor in various types of cancer. However, the role of miR-340 in chemotherapy has not been reported yet. In this study, we found that miR-340 enhanced cisplatin (CDDP)-induced cell death. Induction of miR-340-5p expression decreased the IC50 of CDDP and increased the apoptosis of CDDP-resistant MG-63 and Saos-2 cells. Moreover, miR-340-5p decreased the accumulation of MRP1 and MDR1. We further explored the mechanism underlying the promoting effects of miR-340-5p on CDDP-induced cell death. We identified a potential target of miR-340 in the 3' untranslated region of lysophosphatidic acid acyltransferase (LPAATβ) using the online program Targetscan (http://www.microrna.org). Luciferase reporter assays showed that miR-340 binds to the 3'UTR of LPAATβ. Enforced expression of miR-340-5p decreased the accumulation of LPAATβ in both MG-63 and Saos-2 cells. Silencing LPAATβ decreased the IC50 of CDDP and increased the apoptosis of CDDP-resistant MG-63 and Saos-2 cells, which is consistent with the effect of miR-340-5p on CDDP-induced cell death. Moreover, induced expression of LPAATβ compromised the effects of miR-340-5p on CDDP-induced cell death and accumulation of MRP1 and MDR1. Taken together, our data indicated that miR-340-5p enhanced the sensitivity to CDDP by targeting LPAATβ.

[Effects of bisphenol A on the expression of N-cadherin, Vimentin and FSHR in rat Sertoli cells]

Objective: To explore the effects of BPA on the expression of N-cadherin, Vimentin and FSHR in rat Sertoli cells. Methods: Primary Sertoli cells collected from prepuberty rats (18-21 d) were cultured for 48 h, and then they were treated with 0, 30, 50, 70 μmol/L BPA respectively for 24 h. The methods of MTT, real-time quantitative PCR and Western blotting were utilized to measure the cell ability of Sertoli cells, the mRNA and protein expression levels of N-cadherin, Vimentin and FSHR respectively. Results: Compared with control, the cell abilities of Sertoli cells in 50 μmol/L BPA group and 70 μmol/L BPA group increased significantly (P<0.05) . The cell abilities of Sertoli cells decreased with the increases of exposure doses of BPA. Compared with control, the expression of N-cadherin mRNA only increased in 30 μmol/L BPA group (P<0.05) , the expression of Vimentin mRNA decreased significantly in all doses group of BPA (P<0.05) , the expression of FSHR mRNA increased in all doses group of BPA (P<0.05) . Compared with the control, the protein levels of N-cadherin increased significantly in 50 μmol/L BPA group (P<0.05) , the protein levels of Vimentin decreased significantly in all doses group of BPA (P<0.05) , the protein levels of FSHR decreased significantly in 50 μmol/L BPA group and 70 μmol/L BPA group (P<0.05) . Conclusion: The mechanism of testicular toxicity from BPA might be the alterations of N-cadherin, Vimentin and FSHR by disturbing normal spermatogenesis.

Role of delta-like ligand-4 in chemoresistance against docetaxel in MCF-7 cells

As Notch receptors have been shown to induce chemoresistance, we hypothesized that delta-like ligand-4 (DLL4), a central Notch signalling ligand, might also participate in chemoresistance in breast cancer. To investigate this issue, overexpression of DLL4 was induced by transfection with expression vectors for DLL4 in the human breast cancer cell line Michigan cancer foundation-7 (MCF-7). It was found that DLL4 could be adaptively upregulated by docetaxel (DOC) treatment in a dose-dependent manner, but Notch1 was unaffected. Overexpression of DLL4 could significantly attenuate the cytotoxic effects of DOC by increasing Bcl-2 expression, while decreasing Bax expression, apoptosis rate and DNA damage. The protective effects of DLL4 made cells acquire chemoresistance against DOC and resulted in cancer cell survival. DLL4 is normally regarded as a regulator of vascular development. Our results expanded the understanding of DLL4. Since DLL4 may play an important role in the process of acquiring chemoresistance, it may be a promising target in overcoming chemoresistance in breast cancer.

Preparation and characterization of a de-cellularized rabbit aorta as a promising scaffold in vascular tissue engineering

Development of scaffold is essential for promoting and supporting healing process. This study aims to establish a decellularized rabbit aorta for clinical vascular tissue engineering therapy. We successfully prepared decellularized small-diameter aortic scaffolds and investigated several properties of this engineered vascular tissue scaffolds, including cell adhesion, hydrophilicity, cytotoxicity, biocompatibility. Results showed that decellularized aortas have a porous structure with few cell remnants as examined by histochemistry and scanning electron microscopy. Both vascular smooth muscle cells (VSMCs) and endothelial cells (ECs) cultured on decellularized aortas were adhered and proliferated well. Cell adhesion rates of rat VSMCs and ECs reached to 64.32±2.03% and 52.77±1.19%, respectively. VSMCs were able to migrate into outer surface of scaffolds. Hydrophilisity reached its maximal rate at 519±23% in 12 h. Importantly, no overt cytotoxicity was observed when grown in extraction solution of aortic scaffolds. Lastly, we also engrafted cell-scaffolds subcutaneously into nude mice in vivo. Implanted scaffold structure and proliferation of seeded cells were well maintained up to 8 weeks. In conclusion, we successfully prepared a decellularized rabbit aorta that not only largely maintains its extra-cellular structure, but also shows little toxicity. It may constitute a potential tool as a small diameter scaffold in vascular tissue engineering.

Association of gene polymorphisms in RANKL/RANK/OPG system with hypertension and blood pressure in Chinese women

Recent studies have revealed that the receptor activator of nuclear factor-kappa B ligand/RANK/osteoprotegerin (RANKL/RANK/OPG) system has an important role in vascular calcification, which is contributory to various cardiovascular diseases and intimately linked to the regulation of blood pressure. Therefore, we performed a case-control study to investigate the associations of 21 single-nucleotide polymorphisms (SNPs) in the TNFSF11, TNFRSF11A and TNFRSF11B genes in the RANKL/RANK/OPG system with hypertension and blood pressure in post-menopausal Chinese women. In this study, 503 hypertensive patients and 509 normal controls were recruited. Genotyping was performed using the high-throughput Sequenom genotyping platform. The results showed that two SNPs (rs6567270 and rs4603673) in the TNFRSF11A were associated with hypertension (P=0.010 and P=0.013, respectively) and systolic blood pressure (P=0.024 and P=0.023, respectively). One SNP (rs9646629) in the TNFRSF11A showed significant association with diastolic blood pressure (P=0.031). The results of this study suggest that TNFRSF11A but not TNFSF11 and TNFRSF11B genetic variation is associated with hypertension and blood pressure in Chinese women. The findings provide additional support for the genetic role of RANKL/RANK/OPG system in hypertension and blood pressure regulation.

Polymorphisms in genes in the RANKL/RANK/OPG pathway are associated with bone mineral density at different skeletal sites in post-menopausal women

Association between 22 single nucleotide polymorphisms (SNPs) in the TNFSF11, TNFRSF11A, and TNFRSF11B genes in the RANKL/RANK/OPG pathway with bone mineral density (BMD) in 881 post-menopausal women. Our results suggest that TNFSF11 and TNFRSF11A, but not TNFRSF11B, genetic polymorphisms influence BMD mainly in the femoral neck in post-menopausal Chinese women.

INTRODUCTION

The aim of this study was to assess the relationship of polymorphisms in the TNFSF11, TNFRSF11A, and TNFRSF11B genes in the RANKL/RANK/OPG pathway with bone mineral density (BMD) in a cohort of Chinese post-menopausal women.

METHODS

A cross-sectional study was conducted in 881 post-menopausal women aged 50-89 years. All participants underwent lumbar spinal (LS) and femoral neck (FN) BMD evaluation by dual-energy X-ray absorptiometry. Twenty-two TNFSF11, TNFRSF11A, and TNFRSF11B SNPs were genotyped. We tested whether a single SNP or a haplotype was associated with BMD variations.

RESULTS

Two SNPs in the TNFSF11 gene (rs2277439 and rs2324851) and one in the TNFRSF11A gene (rs7239261) were found to be significantly associated with FN BMD (p = 0.014, 0.013, and 0.047, respectively). Haplotype TGACGT of TNFSF11 rs9525641-rs2277439-rs2324851-rs2875459-rs2200287-rs9533166 was a genetic risk factor toward a lower FN BMD (beta = -0.1473; p = 0.01126). In contrary, haplotype TAGCGT of TNFSF11 rs9525641-rs2277439-rs2324851-rs2875459-rs2200287-rs9533166 was genetic protective factor for LS BMD (beta = 0.3923; p = 0.04917).

CONCLUSIONS

Our findings suggest that TNFSF11 and TNFRSF11A, but not TNFRSF11B, genetic polymorphisms influence BMD mainly in the femoral neck in post-menopausal Chinese women. This contributes to the understanding of the role of genetic variation in this pathway in determining bone health.

Stromal fibroblast-derived miR-409 promotes epithelial-to-mesenchymal transition and prostate tumorigenesis

Tumor-stromal interaction is a dynamic process that promotes tumor growth and metastasis via cell-cell interaction and extracellular vesicles. Recent studies demonstrate that stromal fibroblast-derived molecular signatures can be used to predict disease progression and drug resistance. To identify the epigenetic role of stromal noncoding RNAs in tumor-stromal interactions in the tumor microenvironment, we performed microRNA profiling of patient cancer-associated prostate stromal fibroblasts isolated by laser capture dissection microscopy and in bone-associated stromal models. We found specific upregulation of miR-409-3p and miR-409-5p located within the embryonically and developmentally regulated DLK1-DIO3 (delta-like 1 homolog-deiodinase, iodothyronine 3) cluster on human chromosome 14. The findings in cell lines were further validated in human prostate cancer tissues. Strikingly, ectopic expression of miR-409 in normal prostate fibroblasts conferred a cancer-associated stroma-like phenotype and led to the release of miR-409 via extracellular vesicles to promote tumor induction and epithelial-to-mesenchymal transition in vitro and in vivo. miR-409 promoted tumorigenesis through repression of tumor suppressor genes such as Ras suppressor 1 and stromal antigen 2. Thus, stromal fibroblasts derived miR-409-induced tumorigenesis, epithelial-to-mesenchymal transition and stemness of the epithelial cancer cells in vivo. Therefore, miR-409 appears to be an attractive therapeutic target to block the vicious cycle of tumor-stromal interactions that plagues prostate cancer patients.

Serum and urine chromium concentrations in elderly diabetics

The serum and urine chromium concentrations of 57 diabetics and 55 normal fasting subjects were determined by atomic absorption spectrometry (AAS). Our results indicate that the chromium concentration ranges of serum and urine for diabetics are 0.22-0.36 and 4.54-5.90 microg/L, respectively, significantly lower than 0.66-0.84 7.80-9.68 microg/L for the normal (P<0.001), which implies that the elderly diabetics probably lack chromium. Further, it was found that the urine chromium level of the female diabetics was substantially higher than that of the male in the same age group (P<0.01), whereas the serum chromium level was almost the same. However, the urine chromium concentration increases with aging, no matter who the diabetics or the controls are. The serum chromium concentrations of the 24 cases patients with 2-h oral glucose tolerance test (OGTT) were significantly lower than that of those with empty stomach, whereas the urine chromium exhibits a contrary tendency. Our data indicate that the chromium lost and excreted from human body increases with aging and is related to the diabetics. Thus, it is recommended to supplement a certain amount of chromium to the elderly diabetics according to their nutritional level.

[Rapid detection for antigens of respiratory tract viruses by using series of monoclonal antibody]

A series of monoclonal Antibodies (McAb) against six main respiratory tract viruses(RTV)--respiratory syncytial virus (RSV), Influenza A virus (FluA), influenza B virus(FluB), parainfluenza virus type 1.2.3 (PIV1.2.3) were developed, and were used in APAAP bridge-enzyme assay to rapidly detect the antigens of RTV. Total 260 samples of nasopharyngeal exfoliated cells were collected from young men in Beijing Army suffered from respiratory tract virus infections. The results showed that 18 cases were tested with FluA antigen; 10 with PIV2 antigen and 1 with FluB and another with RSV antigen, respectively. All the positive samples were determined by indirect immunofluorescence assay (IFA) and blocking test and replacement test. It is suggested that the method used in the study be effective in clinical rapid diagnosis and epidemiological survey.

[Preliminary studies on subtypes of respiratory syncytial virus in China]

An analysis of subtypes of 9 respiratory syncytial (RS) viruses isolated from Guangzhou and Nanjing areas of china was carried out with eight Sweden RS-subtype specific monoclonal antibodies (MAbs) and 7 internal anti-RS MAbs. All these MAbs directed against respectively the large Glycoprotein (G), fusion protein (F), nucleoprotein (NP), and phosphoprotein (P) components of the prototype Long strain of RS virus. The patterns of the reactions of these MAbs to the nine isolated strains of RS virus were compared with indirect immunofluorescence assay (IFA), alkaline phosphoesterase-anti alkaline phosphoesterase (APAAP) enzyme-linked assay and Western blotting. The antigenic variations were founded among the strains of RS virus, and two subtypes allocated to the subtype A and B of RS virus by using the eight RS-subtype specific MAbs. Seven out of the 9 isolated strains of RS virus belonged to the subtype A, and two were being to the subtype B. The antigenic diversities were also founded within the same subtype, and the main pronounced difference were observed on the G glycoprotein by using the internal anti-RS MAbs. These findings are potentially important both for vaccine development and for the understanding of clinical and epidemiological characteristics of RS virus.

[Hemodynamic effects of a water soluble extract of Liriope spicata Lour on anesthetized cats]

The effects of water soluble extract of Liriope spicata on acute hemodynamics were studied in anesthetized cats. The results showed that LV dp/dt max was increased by 87%, whereas t-dp/dt max was shortened by 28% after administration of WSEL (1.75 g/kg, iv). At the same time CO, CI, SI, and SVWI were increased by 146, 151, 153, and 194%, respectively. HR was declined slightly. SVR was reduced by about 48%. WSEL (0.7 g/kg, iv) induced an increase of 38% in LV dp/dt max, 44% in CO, 50% in SI and a decrease of 20% in t-dp/dt max and 20% in SVR. Preliminary results indicated that WSEL increased ventricular contractile force and might increase cardiac pump function.