[Clinical management and prognosis for descending necrotizing mediastinitis].

Objective: To investigate the clinical characteristics, treatment experiences and prognostic factors for descending necrotizing mediastinitis (DNM). Methods: A retrospective analysis was performed on the data of 22 patients with DNM diagnosed and treated in Henan Provincial People's Hospital from January 2016 to August 2022, including 16 males and 6 females, aged 29-79 years. After admission, all patients underwent CT scanning of the maxillofacial, cervical, and thoracic regions to confirm their diagnoses. Emergency incision and drainage were performed. The neck incision was treated with continuous vacuum sealing drainage. According to the prognoses, the patients were divided into cure group and death group, and the prognostic factors were analyzed. SPSS 25.0 software was used to analyze the clinical data. Rusults: The main complaints were dysphagia (45.5%, 10/22) and dyspnea (50.0%, 11/22). Odontogenic infection accounted for 45.5% (10/22) and oropharyngeal infection accounted for 54.5% (12/22). There were 16 cases in the cured group and 6 cases in the death group, with a total mortality rate of 27.3%. The mortality rates of DNM typeⅠand typeⅡwere respectively 16.7% and 40%. Compared with the cured group, the death group had higher incidences for diabetes, coronary heart disease and septic shock (all P<0.05). There were statistically significant differences between the cure group and the death group in procalcitonin level (50.43 (137.64) ng/ml vs 2.92 (6.33) ng/ml, M(IQR), Z=3.023, P<0.05) and acute physiology and chronic health evaluation Ⅱ(APACHEⅡ) score (16.10±2.40 vs 6.75±3.19, t=6.524, P<0.05). Conclution: DNM is rare, with high mortality, high incidence of septic shock, and the increased procalcitonin level and APACHE Ⅱ score combined diabetes and coronary heart disease are the poor prognostic factors for DNM. Early incision and drainage combined with continuous vacuum sealing drainage technique is a better way to treat DNM.

[Antiviral effect of hepatitis B virus S gene-specific anti-gene locked nucleic acid in transgenic mice].

Objective: To investigate the antiviral effect of hepatitis B virus (HBV) S gene-specific anti-gene locked nucleic acid (LNA) in transgenic mice. Methods: A total of 30 HBV transgenic mice were randomly divided into blank control group (5% glucose + liposome), unrelated sequence control group, lamivudine control group, antisense LNA control group, and anti-gene LNA group, with 6 mice in each group. The mice in the lamivudine group were given lamivudine by gavage, and LNA was injected via the caudal vein. Quantitative real-time PCR was used to measure serum HBV DNA, ELISA was used to measure serum HBsAg, RT-PCR was used to measure HBV S mRNA level in the liver, and immunohistochemistry was used to measure the level of HBsAg in hepatocytes. Results: At 3, 5, and 7 days after treatment, there were significant changes in the inhibition rates of HBV DNA (37.18%, 50.27%, and 61.46%, respectively) and HBsAg (30.17%, 44.00%, and 57.76%, respectively) achieved by anti-gene LNA (P < 0.01), and there were significant differences between the anti-gene LNA group and the other four control groups (P < 0.05). In the anti-gene LNA group, the relative mRNA expression of HBV S gene was 0.33 and the percentage of HBsAg-positive hepatocytes was 31%, which were significantly different from these two indices in the control groups (P < 0.05). There were no abnormal changes in liver/renal biochemical parameters and HE staining results. Conclusion: Anti-gene LNA targeting at HBV S gene has a strong antiviral effect in transgenic mice, which provides theoretical and experimental bases for gene therapy for HBV.

[Molecular epidemiologic study on Mycobacterium tuberculosis from drug resistance monitoring sites of Guangdong Province, 2015].

Objective: To understand the characteristics of Mycobacterium tuberculosis (MTB) in epidemiology and distribution from Guangdong Province, and to explore the risk factors associated with drug resistance. Methods: A total of 225 clinical strains of MTB collected from 5 drug resistance monitoring sites of Guangdong Province in 2015 were tested by Regions of Difference 105 (RD105) deletion test and 15 loci mycobacterial interspersed repetitive units (MIRU) were used for genotyping. Gene clustering was analyzed using BioNumerics7.6. Drug susceptibility test was tested by proportion method. The statistical analysis used chi-square test and multivariate logistic regression. Results: There were 158 (70.2%) Beijing family strains from the 225 cases. Hunter-gaston index of MIRU loci varied from each other. The MTBs from Guangdong Province were categorized into 2 gene clusters by clustering analysis in which the rate of cluster of complexⅠwas significantly higher than complexⅡ(χ(2) values were 9.331, P values were 0.020). It was found by multivariate logistic regression that Qub11b was associated with resistance to rifampicin and isoniazid (P values were 0.013, 0.012 respectively.), ETR F with resistance to isoniazid, streptomycin, ethambutol and ofloxacin (P values were 0.039, 0.040, 0.023 and 0.003 respectively), Mtub21 with resistance to capreomycin (P values were 0.040), and QUB26 with resistance to ethionamide (P values were 0.047). Conclusions: The genes of MTB from Guangdong Province were of polymorphisms and the distribution of strains were stable. QUB11b, ETR F, Mtub21 and QUB26 could be related to biomarkers for predicting drug resistance.

Development of competitive indirect ELISA for the detection of tetrodotoxin and a survey of the distribution of tetrodotoxin in the tissues of wild puffer fish in the waters of south-east China.

A monoclonal antibody against tetrodotoxin (TTX) was produced from the hybridoma cell line T6D9, which was established by the fusion of Sp2/0 myeloma cells with spleen cells isolated from a Balb/c mouse immunized with the TTX-keyhole limpet hemocyanin (KLH) conjugate. This monoclonal antibody belongs to the IgG1 subclass; the affinity constant of the antibody is 2.4 × 10(-8) mol l(-1). The relative cross-reactivity of the antibody with TTX was 100%, but with saxitoxin, KLH and bovine serum albumin (BSA) it was less than 1%, respectively. The titre of the antibody in ascites was 6.4 × 10(6); the reference working concentration was 1:1.2 × 10(5). By using this monoclonal antibody, a competitive indirect enzyme-linked immunoabsorbant assay (ELISA) for the analysis of TTX was developed. The linear portion of the dose-response curve of TTX concentration was in range 5-500 ng ml(-1). The limit of detection was 5 ng ml(-1) according 10% inhibition with TTX to anti-TTX monoclonal antibody. The concentration of TTX inhibiting 50% of antibody binding was about 50 ng ml(-1). The recoveries from TTX spiked samples were 79.5-109.5%. In addition, the toxicity of some wild puffer fish specimens captured from south-east China and the Yangzi River in Jiangsu province was determined. The results indicate that the toxicity and toxin tissue distribution vary in different species of wild puffer fish.

Submucosal tumor extension in hypopharyngeal cancer.

OBJECTIVES: To study the incidence and extent of submucosal tumor extension in hypopharyngeal cancer and to evaluate the impact on the tumor recurrence and overall survival rates. METHODS: Fifty-seven resected specimens of hypopharyngeal cancer were studied in detail from January 1986 to December 1989 by use of the whole-organ, step-serial sectioning technique. RESULTS: Three types of submucosal tumor extension could be identified. Type I extension was characterized by a tumor with a smooth round contour that extended submucosally. The mucosa was thereby elevated and was detectable on gross inspection at operation. In type II extension, tongues and islands of tumor infiltrated within the submucosa, and these were not noticeable on gross examination. Skip metastasis in the submucosa where the submucosal tumor was completely separated from the main tumor bulk was classified as type III extension. Thirty-three patients (58%) had submucosal tumor extension. The frequencies (and extents of submucosal tumor extension) in the superior, medial, lateral, and inferior directions were 16% (3-10 mm), 37% (2-37 mm), 26% (2-37 mm), and 28% (3-35 mm), respectively. Two thirds of the submucosal extension was type I (22 of 33), and only 1 patient had a true skip lesion submucosally (type III extension). Type II submucosal extension was found in one third of the patients (11 of 33). This occurred significantly more often in the patients who had received radiotherapy before surgery (82% [9/11]; P < .001; 95% confidence interval, 1.28-4.44). The presence of submucosal tumor extension had no effect on the tumor recurrence and overall survival rates. CONCLUSIONS: The incidence of submucosal tumor extensions in hypopharyngeal cancer is high (58%), but most (67%) of them can be detected grossly at operation. The presence of submucosal tumor extension does not adversely affect the survival and tumor recurrence rates.

[Studies on the molecular epidemiology of poliovirus type 1 in China].

A strain of poliovirus type 1 isolated from an endemic in Shandong Province in 1988 and three strains of poliovirus type 1 isolated from an endemic in Xinjiang in 1990 were analysed by dot blot hybridization with Sabin I specific probe and PCR amplification with Sabin I specific primers. They were proved to be non-Sabin-like poliovirus. The nucleotide sequences of VP1-2A junction region of four poliovirus type 1 isolates were analysed. It was found that the nucleotide diversity of four isolates with Sabin I was equal to or greater than 16.7%. This finding proved that they were wild polioviruses and greatly different fromSabin I. It was also found that the nucleotide sequence diversity among three strains from Xinjiang was very small (less than 2.6%) with identical amino acid sequences. This indicated that the three Xinjiang strains belonged to the same genotype. While the difference of Shandong strain from the three Xinjiang strains was between 14. 0% to 15.33% in nucleotide sequence and 2.0% to 4.0% in amino acids. This indicated that Shandong strain was apparently different from three Xinjiang strains and it belonged to another wild genotype which had a different history of evolution.

[On the relation of five flavors and toxicity of Chinese materia medica].

The relation between the "five flavours" of Chinese materia medica and toxicity has never been discussed in Chinese medicine and pharmacology. This paper presents that both the efficacy and toxicity of Chinese materia medica are caused by some material base-the five flavours, of which the acrid and bitter are the most toxic, the sweet the least, and the sour and salty the medium toxic.