[Correlative factors analysis and predictive model construction of intestinal flora imbalance during acute exacerbation of chronic obstructive pulmonary disease].

Objective: To explore correlative factors and construct predictive model of intestinal flora imbalance in patients with acute exacerbation of Chronic Obstructive Pulmonary Disease (COPD). Methods: The patients in acute exacerbation stage of COPD (AECOPD) hospitalized in Yixing People's Hospital from January 1 to December 31, 2019 were included. According to the clinical symptoms and results of fecal examination, the subjects were divided into case group (n=45) and control group (n=83). Multivariate logistic regression was used to analyze the correlative factors of intestinal flora imbalance in AECOPD patients. The prediction model of intestinal flora imbalance in patients with AECOPD was constructed according to the results of factor logistic regression analysis, and the effectiveness of the prediction model was evaluated by receiver operating characteristic (ROC) curve analysis. Results: The ages of subjects in case group and control group were (76±9) and (74±8) years old, respectively, among which males accounted for 80.0% (36/45) and 69.9% (58/83), respectively. The multivariate logistic regression model analysis showed that serum albumin concentration, frequency of acute exacerbation ≥2 times/year, complicated with chronic cor pulmonale and diabetes mellitus were correlative factors of intestinal flora imbalance in patients with AECOPD. The OR (95%CI) were 0.98 (0.80-0.97), 3.70 (1.79-11.72), 2.62 (1.46-10.80) and 3.85 (1.17-8.58), respectively. The prediction model of intestinal flora imbalance was logit P=3.858-0.13×serum albumin consentration+1.52×acute exacerbation ≥2 times/year+1.379×chronic cor pulmonale+1.155×diabetes mellitus. The area under the ROC curve of this model was 0.847 and the sensitivity and specificity of the prediction model were 88.9% and 71.1%, respectively. Conclusions: Serum albumin, frequency of acute exacerbation ≥2 times/year, complicated with chronic cor pulmonale and diabetes mellitus are correlative factors of intestinal flora imbalance in patients with AECOPD. The predictive model shows high clinical value in predicting intestinal flora imbalance in patients with AECOPD.

A strain of pathogenic Bacillus subtilis results in brain damage in ducklings when co-infected with Riemerella anatipestifer.

Bacillus subtilis is a Gram-positive bacterium widely used in medicine and agriculture. So far, little is known about its pathogenicity in animals. In this study, a strain of Bacillus subtilis, HFBF-B11 isolated from brain tissue of ducklings co-infected with Riemerella anatipestifer was characterized. The strain demonstrated consistent characteristics of B. subtilis in staining and morphological, biochemical and physiological analyses. Moreover, its DNA sequence, which was obtained via PCR sequencing of 16S rRNA, exhibited 99% homology with the B. subtilis reference strain. In in vitro cultures HFBF-B11 exhibited ß-hemolysis. The results of experiments showed that a single infection of HFBF-B11 in 9-day-old ducklings did not result in clear clinical symptoms. However, following co-infection with HFBF-B11 and R. anatipestifer, the animals demonstrated liver injury and blood-brain barrier disruption leading to infection and brain damage with a mortality rate of 100%. These results suggest that the HFBF-B11 strain of B. subtilis is an opportunistic pathogen of ducklings. This is the first report about the isolation of a B. subtilis strain with pathogenicity in ducklings.

Clonal analysis of gastric carcinoma and precancerous lesions and its relation to Ki-67 protein expression.

The pathogenesis of intestinal carcinoma is characterized as progressing through multiple steps, which begin with atrophic gastritis followed by intestinal metaplasia, dysplasia and carcinoma. However, the clonal status of gastric precancerous lesions and its association with proliferative kinetics have not been fully understood. In this study, gastric lesions and normal epithelial cells were isolated from formalin-fixed paraffin embedded tissues using a laser capture microdissection (LCM) system, the clonality was analyzed with human androgen receptor gene (HUMARA) polymerase chain reaction (PCR), and the PCR products were examined using Applied Biosystems 3730 DNA Analyzer. The relationship between the clonal status and Ki-67 protein expression was also investigated. Ki-67 was detected by two-step immunohistochemical staining. 5/32 intestinal metaplasia lesions, 10/45 low grade intraepithelial neoplasia, 25/36 high grade intraepithelial neoplasia and 20/20 intestinal gastric carcinoma were of monoclonal origin. Similar to monoclonal inactivation, the expression rate of Ki-67 also increased along the multi-step gastric carcinogenesis. Clonal status was associated with the expression rate of Ki-67 to a certain extent, which may be useful in assessing susceptibility to gastric carcinoma. Key words: gastric carcinoma; precancerous lesion; clonal analysis; Ki-67.

Expression of Cdv-iR gene in mouse epididymis as revealed by in situ hybridization.

We have previously studied mouse Cdv (carnitine deficiency-associated gene expressed in ventricle)-1 related gene Cdv-1IR and its human counterpart CDV-1R, and revealed that mouse Cdv-1R was predominantly expressed in testis by multiple tissue northern analysis. To further localize the Cdv-1R mRNA in mouse testis and epididymis tissue, in situ hybridization study was reported in this article. In the adult mice, the Cdv-1R expression was intensively found in the epithelial cells of the caput and corpus epididymis, whereas it was moderately detected in the initial segment, and weakly in the cauda epididymis. In the seminiferous tubles of the testis, no obvious hybridization signals were observed above the background level. This Cdv-1R region-specific expression pattern in the epididimis suggests Cdv-1R may play an important role in sperm maturation. Moreover, considering the Cdv-1R has a similar expression distribution in epididymis to the OCTN2, it would appear that Cdv-1R might be involved in the carnitine pathway in the epididimis.

In situ RT-PCR detection of hepatitis C virus genotypes in Chinese patients with hepatocellular carcinoma.

The correlation of hepatitis C virus genotypes and the development of hepatocellular carcinoma is still controversial. The most pertinent studies are conducted by seroepidemiological methods. It has been suggested that tissue RT-PCR may be more efficient than serological testing for hepatitis C virus RNA. The purpose of this study was to investigate the infectious status of hepatitis C virus genotypes in hepatocellular carcinoma tissue for revealing the role of hepatitis C virus genotypes in carcinogenesis of hepatocellular carcinoma. Hepatitis C virus genotypes in cancerous and noncancerous liver tissues of 95 Chinese patients with hepatocellular carcinoma were analyzed by a modified type-specific in situ reverse transcription polymerase chain reaction (RT-PCR) method. Hepatitis C virus genotypes were simultaneously examined by Okamoto's method using extracts from hepatocellular carcinoma tissues. The hepatitis C virus genotypes in hepatocellular carcinoma tissues were found including 1b, 2a, mixed type (1b+2a) and 3a in 13, 23, 2 and 4 samples respectively. There was no significant difference in either the positivities between 1b (13.7%, 13/95) and 2a (24.2%, 23/95) (P>0.05) or the staining intensity and distribution of positive cells between 1b and 2a (p>0.05). No statistically significant difference was found between the two virus genotypes in main clinico-pathologic parameters of hepatocellular carcinoma. The localizations of hepatitis C virus RNA-positive signals were mainly cytoplasmic (22/36) in noncancerous regions, but nucleocytoplasmic (19/36) or nuclear (3/36) in cancerous regions. The positive nucleocytoplasmic/nuclear signals of genotype 1b (11/13) in hepatocellular carcinoma were seen more frequently than those of genotype 2a (11/23) (P<0.05). The discordant hepatitis C virus 2a and 1b positivities in serum samples and in cancerous tissues of hepatocellular carcinoma patients were also found, suggesting that the detection of serum hepatitis C virus genotypes in the patients with hepatocellular carcinoma may not reflect the actual status of hepatitis C virus genotypes in cancerous tissue. The pathogenetic significance of existence of hepatitis C virus gene in the nucleus of hepatocytes and malignant cells needs further investigation.

[Detection of poliovirus by digoxigenin-labeled cDNA probe prepared by PCR technique].

A study including reverse transcribed cDNAs of Sabin I, II, III virus used as templates and digoxigenin-labeled dUTP added to the reaction solution was carried out. After amplification, digoxigenin-labeled poliovirus cDNA probe was prepared by this PCR technique. Results showed that the direct preparation of digoxigenin-labeled poliovirus cDNA probe by PCR is a convenient and rapid method with a high labeling rate. Compared with neutralization test, the probe has the advantages of more rapid, more sensitive and more specific for poliovirus typing.