The role of Xpert MTB/RIF using bronchoalveolar lavage fluid in active screening: insights from a tuberculosis outbreak in a junior school in eastern China.

Background: Tuberculosis (TB) outbreaks in schools present a public health challenge. In order to effectively control the spread of transmission, timely screening, accurate diagnosis and comprehensive epidemiological investigations are essential. Methods: In July 2021, a TB outbreak occurred in a junior high school in Y City, Zhejiang Province. Students and faculty were screened for TB by symptom screening, chest radiography, and tuberculin skin test during four rounds of contact screenings. For sputum smear-negative and sputum-scarce patients, bronchoscopy was used to collect BAL samples for Xpert Mycobacterium tuberculosis/rifampin (MTB/RIF). Whole-genome sequencing and bioinformatics analysis were performed on isolates to identify the strains of MTB isolates and predict drug resistance. Results: Between July 2021 and November 2021, a total of 1,257 students and faculty were screened for TB during screenings. A total of 15 students (1.2% of persons screened) aged 15 years were diagnosed with TB. Eighty percent (12/15) of the cases were laboratory-confirmed (10/12 [83%] Xpert MTB/RIF-positive, 2/12 [17%] culture-positive). Most cases (12/15 [80%]) were in students from Class 2. All cases were asymptomatic except for the index case who had symptoms for more than two months. Seven MTB isolates were collected and belonged to lineage 2. Conclusion: Our findings demonstrated the potential of Xpert MTB/RIF using BAL as a screening tool in school TB outbreaks for sputum smear-negative and sputum-sparse suspects, which may not only rapidly improves diagnostic accuracy, but also facilitates epidemiological investigations and homology analysis.

Incidence and prevalence of tuberculosis in systemic lupus erythematosus patients: A systematic review and meta-analysis.

Background: Systemic lupus erythematosus (SLE) patients are particularly susceptible to infections, such as pulmonary tuberculosis (PTB) and extrapulmonary tuberculosis (EPTB). This meta-analysis aimed to determine the incidence and prevalence of tuberculosis (TB) in SLE patients. Methods: The Web of Science, PubMed, Cochrane Library, and Chinese National Knowledge Infrastructure databases were searched for articles of relevant studies published from the dates the databases were established until April 30, 2022. The I2 statistic and Q test were used to evaluate heterogeneity among the analysed studies. Random-effects models were utilised and subgroup analyses were conducted for analysis of the study data. Results: A total of 35 studies with 46,327 SLE patients were eligible for analysis. The incidence and prevalence of TB among the SLE patients were 1.16 per 100 person-years (95% confidence interval (CI): 0.69-1.93) and 3.59% (95% CI: 2.57%-5.02%), respectively. The pooled prevalence of SLE-PTB and SLE-EPTB was 2.46% (95% CI: 1.73%-3.51%) and 1.42% (95% CI: 0.98%-2.06%), respectively. Subgroup analyses showed that the incidence of SLE-TB was higher in Africa and in countries with a high TB burden than in countries with a low TB burden. The prevalence of SLE-TB was elevated in Asia, in patients taking a mean daily dose of glucocorticoids ≥20 mg, in studies with small sample sizes (n <1000) and ended before 2001. Conclusions: The available evidence suggests that both the incidence and prevalence of TB in SLE patients are high. This study provides a more specific understanding of SLE-TB, which can help health policymakers in the development of preventive strategies for reducing the SLE-TB burden.

Incidence and prevalence of pulmonary tuberculosis among patients with type 2 diabetes mellitus: a systematic review and meta-analysis.

BACKGROUND: The epidemic of type 2 diabetes mellitus (T2DM) poses a great challenge to pulmonary tuberculosis (PTB) control. However, the incidence and prevalence of PTB among T2DM patients has not been fully determined. This meta-analysis aimed to provide the estimation on the global incidence and prevalence of PTB among T2DM patients (T2DM-PTB). METHODS: Online databases including Web of Science, PubMed, China National Knowledge Infrastructure and Cochrane Library were searched for all relevant studies that reported the incidence or prevalence of T2DM-PTB through 31 January 2022. Pooled incidence and prevalence of T2DM-PTB with 95% confidence interval (CI) was estimated by the random-effect model. All statistical analyses were performed using R software. RESULTS: A total of 24 studies (14 cohort studies, 10 cross-sectional studies) were included. The pooled incidence and prevalence of T2DM-PTB were 129.89 per 100,000 person-years (95% confidence interval (CI): 97.55-172.95) and 511.19 per 100,000 (95% CI: 375.94-695.09), respectively. Subgroup analyses identified that the incidence of T2DM-PTB was significantly higher in Asia (187.20 per 100,000 person-years, 95% CI: 147.76-237.17), in countries with a high TB burden (172.04 per 100,000 person-years, 95% CI: 122.98-240.68) and in studies whose data collection ended before 2011 (219.81 per 100,000 person-years, 95% CI: 176.15-274.28), but lower in studies using International Classification of Diseases-10 codes (73.75 per 100,000 person-years, 95% CI: 40.92-132.91). The prevalence of T2DM-PTB was significantly higher in countries with a high TB burden (692.15 per 100,000, 95% CI: 468.75-1022.04), but lower in Europe (105.01 per 100,000, 95% CI: 72.55-151.98). CONCLUSIONS: This systematic review and meta-analysis suggests high global incidence and prevalence of PTB among T2DM patients, underlining the necessity of more preventive interventions among T2DM patients especially in countries with a high TB-burden. Key messagesA total of 24 studies (14 cohort studies, 10 cross-sectional studies) containing 2,569,451 T2DM patients were included in this meta-analysis.The pooled incidence and prevalence of T2DM-PTB are 129.89 per 100,000 person-years (95% CI: 97.55-172.95) and 511.19 per 100,000 (95% CI: 375.94-695.09) respectively.The incidence of T2DM-PTB was significantly higher in Asia, in countries with a high TB burden and in studies whose data collection ended before 2011, but lower in studies using International Classification of Diseases-10 codes.The prevalence of T2DM-PTB was significantly higher in countries with a high TB-burden, but lower in Europe.

Treatment outcomes of patients with multidrug and extensively drug-resistant tuberculosis in Zhejiang, China.

BACKGROUND: The aim of this study was to assess the treatment outcomes of multidrug and extensively drug-resistant tuberculosis (M/XDR-TB) in Zhejiang, China and to evaluate possible risk factors associated with poor outcomes of M/XDR-TB. METHODS: Two-hundred-and-sixty-two patients having M/XDR-TB who received the diagnosis and treatment at nine referral hospitals from 1 January 2016 to 31 December 2016 in Zhejiang, China were included. All patients received second-line regimens recommended by WHO under the DOTS-Plus strategy. RESULTS: Among the 262 patients, the treatment success rate was 55.34% (n = 145) with 53.44% (n = 140) cured and 1.91% (n = 5) who completed treatment, 62 (23.66%) failed, 27 (10.31%) died, 16 (6.11%) defaulted and 12 (4.58%) transferred out. Forty (64.52%) of the 62 M/XDR-TB patients who failed treatment were due to adverse effects in the first 10 months of treatment. Eighteen patients (6.37%) had XDR-TB. Treatment failure was significantly higher among patients with XDR-TB at 50% than that among patients with non-XDR-TB at 21.72% (P = 0.006). Failure outcomes were associated with a baseline weight less than 50 kg (OR, 8.668; 95% CI 1.679-44.756; P = 0.010), age older than 60 years (OR, 9.053; 95% CI 1.606-51.027; P = 0.013), hemoptysis (OR, 8.928; 95% CI 1.048-76.923; P = 0.045), presence of cavitary diseases (OR, 10.204; 95% CI 2.032-52.631; P = 0.005), or treatment irregularity (OR, 47.619; 95% CI 5.025-500; P = 0.001). CONCLUSION: Treatment outcomes for M/XDR-TB under the DOTS-Plus strategy in Zhejiang, China were favorable but still not ideal. Low body weight (< 50 kg), old age (> 60 years), severe symptoms of TB including cavitary disease, hemoptysis and irregular treatment were independent prognostic factors for failure outcomes in patients with M/XDR-TB.

Epidemiological Characteristics and Their Influencing Factors Among Pulmonary Tuberculosis Patients With and Without Diabetes Mellitus: A Survey Study From Drug Resistance Surveillance in East China.

BACKGROUND: The burden of pulmonary tuberculosis (TB) and diabetes mellitus (DM) have become serious global concerns, while the comprehensive evaluations of DM status and drug resistance in TB patients are still lacking. METHODS: All details of TB cases were collected from drug resistance monitoring sentinels in Zhejiang province. Fisher's exact test or Pearson chi-square test (χ2) was used to compare the baseline characteristics among TB with different DM statuses. The logistic regression model was used to estimate the relationship between DM and different drug resistance spectra. Univariate analysis and multivariate logistic model were used to explore the possible risk factors of drug resistance in TB patients with DM and no DM. RESULTS: 936 TB cases with smear-positive in Zhejiang province were collected, in which 76 patients (8.12%) owned the co-morbidity of DM. TB-DM prevalence was higher in older, Han nationality, employed, accompanied by no health insurance and hepatitis B status. Among 860 cases of TB-no DM and 76 cases of TB-DM, drug resistance-TB accounted for 31.51% and 23.68% (P > 0.05), MR-TB accounted for 15.93% and 14.47% (P > 0.05), respectively. MDR-TB was 4.88% and 6.58% (P > 0.05). The incidence of poly-drug resistant tuberculosis (PDR-TB) in TB-no DM patients (10.70 vs. 2.63%, OR: 4.43; 95% CI, 1.07-18.36) was higher than that in the TB-DM group (P < 0.05). In univariate and multivariate analysis, none of the basic factors were statistically significant with drug resistance among TB-DM cases (all P > 0.05). Retreatment was the risk factor of drug resistance among TB-no DM cases. CONCLUSIONS: Our results showed that the drug resistance rate of the TB-DM group was not higher than that of the TB-no DM group. Patients with TB-no DM were at a higher risk for PDR-TB, but not for MDR-TB, MR-TB, and drug resistance-TB. Special attention should be paid to TB-no DM patients who have been previously treated. In the future, large-scale and well-designed prospective studies are needed to clarify the impact of DM on the drug-resistance among TB.

Multidrug-resistant tuberculosis transmission among middle school students in Zhejiang Province, China.

BACKGROUND: Despite significant advancements in the treatment and diagnosis of tuberculosis (TB) over the past decade, drug-resistant TB remains an increasing threat to public health. TB outbreaks are most commonly reported in schools considering the delay in TB diagnosis, sustained contact, and overcrowding observed in schools. This report describes multidrug-resistant TB (MDR-TB) transmission in a school in Zhejiang Province. We aimed to raise awareness regarding MDR-TB transmission among students. CASE PRESENTATION: The index patient was a 16-year-old girl in the second year of junior middle school in Zhejiang Province, China, who had been experiencing persistent cough and expectoration for 37 days since 1 March 2014. She tested positive for smear pulmonary and extrapulmonary TB on 8 April 2014 and was subsequently diagnosed with MDR-TB on 1 May 2014. However, the patient was resistant to isoniazid, rifampicin, ethambutol, and streptomycin. Thus, she was suspended from school for anti-TB treatment. All 54 students who were in close contact with the index patient in the same class were screened, and 5 tested positive on the tuberculin skin test. Their exposure time to the index patient was approximately 37 days. Three classmates were subsequently diagnosed with MDR-TB, with similar resistance profiles nearly two years later. Their average discovery delay was 55 days. These three classmates were also suspended from school for anti-TB treatment. During the treatment period, four students visited the local TB-designated hospital for further consultation every month and were followed up once a month by the local community health service center until they were completely cured. CONCLUSIONS: Discovery delay for an index patient played a primary role in MDR-TB transmission inside the school. To immediately detect TB, morning examinations in schools should be performed. TB trackers and case managers should work closely with public health workers and physicians in cases of TB outbreaks or transmissions involving students. Moreover, individuals who are in close contact with MDR-TB patients should undergo careful clinical follow-up for at least two years. Implementing a joint examination strategy to ensure early detection, diagnosis, and treatment of MDR-TB transmission is recommended.

Multidrug-resistant Tuberculosis Burden among the New Tuberculosis Patients in Zhejiang Province: An Observational Study, 2009-2013.

BACKGROUND: Screening on multidrug-resistant tuberculosis (MDR-TB) has been limited to the serious TB subpopulations excluding the new TB patients. This study aimed to examine MDR-TB burden among the new TB patients. METHODS: We conducted a study in Zhejiang Province during 2009-2013 to screen for MDR-TB patients among the low MDR-TB risk patients and five subpopulations of high MDR-TB risk patients. The number, prevalence, and trend of MDR-TB were compared while the logistic regression model was used to examine risk factors related to MDR-TB. RESULTS: A total of 200 and 791 MDR-TB cases were, respectively, identified from the 9830 new TB cases and 2372 high-risk suspects who took MDR-TB screening from 2009 to 2013. The MDR-TB rates went down in both of the new TB patients and five MDR-TB high-risk groups over the study time, but the percentage of MDR-TB patients identified from the new TB patients in all diagnosed MDR-TB cases kept stable from 28.3% in 2011 to 27.0% in 2012 to 26.0% in 2013. CONCLUSIONS: The study indicated that MDR-TB burden among new TB patients was high, thus screening for MDR-TB among the new TB patients should be recommended in China as well as in the similar situation worldwide.

[Optimization of processing parameters of microwave-assisted extraction technique of Moerella iridescens polysaccharide by response surface methodology].

OBJECTIVE: To optimize the extraction conditions of polysaccharide from Moerella iridescens with the microwave-assisted extraction technology by Response surface methodology (RSM). METHODS: Extracting temperature, extracting time and the solvent/solid ratio were selected as factors. The yield of polysaccharide was used as the responsive value. Based on the single factors experiments, a three-factor-three-level experiments design was developed by Box-Benhken central composite design method. The response surface method was employed to analyze the results of experiments. RESULTS: The optimum extraction conditions of polysaccharide were as follows: extracting temperature was 45 degrees C, extracting time was 2.7 h and solvent/solid ratio was 50:1. The predictive maximum yield of polysaccharide was 1.17%. The average yield of polysaccharide in 3 validation experiments was 1.19% and the relative error was 1.70%. CONCLUSION: RSM analysis optimizing the extraction conditions for polysaccharide from Moerella iridescens is feasible, which can improve the extraction rate of Moerella iridescens polysaccharide.

[Extraction and purification of acidic polysaccharide from Moerella iridescens].

OBJECTIVE: To optimize extraction and purification methods of acidic polysaccharide from Moerella iridescens (MIAP). METHODS: With alkali extraction process and orthogonal experiment,the time consumption,temperature,pH value of the solution and alcohol concentration during the extraction were optimized. The crude products were deprived of protein,pigment and ion,then were purified with DEAE-cellulose ion-exchange chromatography and verified with Sephadex G-100 and cellulose acetate membrane electrophoresis,and examined with infrared spectrum. RESULTS: The optimized extraction conditions were as follows: extraction time 6 h,extraction temperature 70 degree,the solution pH 8.0 and the concentration of alcohol precipitation 70%. Intuitive features showed that the MIAP was pure white crystalline granular with slight dark brown color. The purification results demonstrated that the target MIAP was eluted and identified as a homogeneous components by DEAE-cellulose ion exchange column,Sephadex G-100 and cellulose acetate membrane electrophoresis. Infrared spectral scanning suggested that MIAP was α-D-type terminated glucopyranose. Intuitive features showed that MIAP was soft and cottony white. CONCLUSION: The extraction process with orthogonal test has been optimized and the acidic polysaccharide from Moerella iridescens is successfully isolated.

[Investigation analysis on public awareness of tuberculosis knowledge in Zhejiang province, 2010].

OBJECTIVE: To investigate the status of awareness on tuberculosis (TB) in the public and its impact factors in Zhejiang province. METHODS: A multi-stage sampling was applied. Around 6600 subjects were enrolled for questionnaire survey from December 2010 to January 2011 in Zhejiang province. Survey data were input by EpiData 3.0 software, and the the status of awareness on tuberculosis (TB) in the public and impact factors were analyzed by SPSS 13.0 software package. RESULTS: A total of 6546 subjects were investigated, the response rate was 99.18% (6546/6600), 3306 were male and 3240 were female, the age of subjects was (44.90 ± 12.40) year-old. The total key information awareness rate of TB was 45.66% (14 944/32 730). 65.70% (4301/6546) knowing the transmission route, 33.30% (2180/6546) knowing the symptom of TB, 39.21% (2567/6546) knowing where to go when suspected suffering TB, 38.28% (2506, 6546) knowing national free anti-TB drug supply and examination of infectious TB patients, 51.79% (3390/6546) knowing TB is curable in most case. As for the the key information awareness rate, among senior high school or above, primary high school, primary school or below were 57.19% (3257/5695), 52.07% (6 066/11 650), 36.54% (5 621/15 385), respectively; among birthplace in city, rural areas were 54.70 (1745/3190), 44.68% (13 199/29 540), respectively; Amone male, female were 47.11% (7 788/16 530), 44.17% (7 156/16 200); among different occupations, cadre or staff was highest (59.43%, 1 563/2 630), whereas students was lowest (40.33%, 492/1220); among different age groups, subjects aged beyond 50 years was lowest (39.75%, 5 189/13 055). The total key information awareness rate among above different population groups showed statistically difference (all P values < 0.01). CONCLUSION: Awareness of knowledge for prevention and therapy of tuberculosis in Zhejiang public was insufficient and imbalanced among subjects with different social demographic characteristics.

HPV E6 down-regulation and apoptosis induction of human cervical cancer cells by a novel lipid-soluble extract (PE) from Pinellia pedatisecta Schott in vitro.

AIM OF THE STUDY: To evaluate the cytotoxicity and apoptosis induction effects of a novel lipid-soluble extract (PE) from Pinellia pedatisecta Schott on CaSki, HeLa and HBL-100 cells. Particularly, the effect of PE on HPV E6 gene expression was tested, and the mechanism of its apoptosis induction effect was also studied. MATERIALS AND METHODS: Cell viability was measured by the MTT assay. DAPI staining and flow cytometric analysis (FCM) were used to identify apoptotic cells in PE-treated CaSki, HeLa, and HBL-100 cells. Expression of the HPV E6 gene in CaSki and HeLa cells was detected by real-time RT-PCR and western blot analysis. Apoptosis-associated genes were examined by RT-PCR and western blot analysis in CaSki cells. RESULTS: PE inhibited the growth of CaSki and HeLa cells in a time- and dose-dependent manner, but it had no obvious inhibiting effect on HBL-100 cells except at a relatively high dose (500 µg/mL). PE could induce apoptosis in CaSki and HeLa cells in a time-dependent manner but not in HBL-100 cells. HPV E6 mRNA and protein were decreased significantly by PE. Caspase-8, caspase-3, Bax, P53 and P21 mRNAs as well as proteins were increased while Bcl-2 mRNA and protein were decreased significantly by 24 h of PE treatment. CONCLUSIONS: PE can function as a tumor suppressor by inducing apoptosis in human cervical cancer cells but it has little side effect on normal cells. It probably acts via mitochondria-dependent and death receptor-dependent apoptotic pathways. HPV E6 may be the key target of its action.

Role of interleukin-18 in the development of acute pulmonary injury induced by intestinal ischemia/reperfusion and its possible mechanism.

BACKGROUND AND AIMS: Lung injury is an important target for the systemic inflammatory response associated with intestinal ischemia/reperfusion (I/R). In the present study, the role of interleukin (IL)-18 in the development of acute pulmonary injury induced by intestinal I/R and its possible mechanism in relation to the increased activity of inducible nitric oxide synthase and tumor necrosis factor (TNF)-alpha were investigated. METHODS: Mice were randomly divided into three groups: normal control group without operation; sham group with sham operation; and I/R group in which mice underwent superior mesenteric artery occlusion for 30 min followed by reperfusion for 3 h. Each group received pretreatment with exogenous IL-18, anti-IL-18 neutralizing antibody or L-NIL, the selective inhibitor of inducible nitric oxide synthase, 30 min before ischemia. The expression of TNF-alpha was detected by reverse transcription-polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assay (ELISA). Lung injury was evaluated by means of Evans blue dye (EBD) concentration, myeloperoxidase (MPO) activity and morphological analysis. RESULTS: The experimental results showed that both in the sham-operated and I/R groups of animals, pretreatment with exogenous IL-18 clearly enhanced pulmonary MPO activity, microvascular leakage and the expression of TNF-alpha mRNA and protein. In contrast, IL-18 did not increase the TNF-alpha level and degree of lung injury, although it clearly enhanced the pulmonary MPO activity in normal animals. Meanwhile, IL-18 antibody given prior to ischemia led to a reduction in the sequestration of neutrophils, extravasation of EBD and downregulation of the serum level of TNF-alpha in the I/R group of animals. In addition, selective inhibition of inducible nitric oxide synthase (iNOS) that inhibited plasma extravasation and pulmonary injury without affecting the MPO activity could be demonstrated in all treated animals. CONCLUSIONS: These data suggested a role of IL-18 in the activation and sequestration of neutrophils in lungs. Our results were consistent with the hypothesis that increased sequestration of neutrophils and microvascular leakage might, respectively, relate to the increased IL-18 level and the elevation of TNF-alpha/iNOS activity, and these two aspects might synergically contribute to intestinal I/R-induced pulmonary dysfunction.

[Effects of beta-sitosterol on microtubular systems in cervical cancer cells].

OBJECTIVE: To investigate beta-sitosterol's inhibitory effects on SiHa cells' growth, and the effects on microtubular system in SiHa cell. METHODS: Proliferation inhibition of SiHa cell line was evaluated by MTT assay. Cell cycle of SiHa cells treated with beta-sitosterol was analyzed by flow cytometry. The expression and distribution of microtubule and microtubule associated protein 2 in SiHa cells were investigated by confocal microscopy. Immunoblotting analysis was used to determine tubulin alpha, microtubule associated protein 2, and the proportion of polymerization of tubulin. RESULTS: beta-sitosterol could obviously inhibit the proliferation of SiHa cells, and induce the accumulation of cells in S phase (rather than the G2/M phase) and mitotic arrest in the cell cycle. Confocal microscopy showed an abnormal microtubular network in SiHa cell treated with beta-sitosterol for 5 days, and the expression of microtubule associated protein 2 was marked down-regulated. Further analysis by immunoblotting confirmed the down-regulation of beta-sitosterol on the expression for both microtubule associated protein 2 and tubulin alpha. Moreover, beta-sitosterol reduced the proportion of polymerization of microtubule in a time-dependent manner. CONCLUSION: beta-sitosterol could down-regulate the expression of tubulin alpha and microtubule associated protein 2 in SiHa cells, and inhibit the microtubular polymerization. Our results suggested an anti-microtubule characteristic of beta-sitosterol which might contribute to the proliferation inhibition of SiHa cells.

Cloning and characterization of a new isoform of mouse interleukin-18.

Interleukin-18 (IL-18) is a novel proinflammatory cytokine with potent interferon (IFN)-lambda inducing activity that plays an important biological role in the enhancement of the activity of natural killer cells and cytotoxic T lymphocytes. In this study, we have identified a novel short form of IL-18 in mouse, named IL-18s. IL-18s might be an alternative splicing variant of IL-18 and its cDNA contains a 57 bp in-frame deletion. Like IL-18, IL-18s is also widely expressed in mouse tissues. It was suggested that IL-18s might have a caspase-1-dependent mechanism for maturation and secretion similar to that of IL-18: when transfected in COS-7 cells, pro-IL-18s (22 kDa) could be detected, and the mature IL-18s (16 kDa) could also be detected when combined with caspase-1. We observed that recombinant mouse IL-18s did not show any IL-18-like function, and IL-18s could enhance the ability of IL-18 to increase IFN-lambda production by approximately 40% in mouse splenocytes. This effect was observed primarily at relative low concentrations of IL-18, suggesting that IL-18s might regulate the activity of IL-18 in the physiological conditions.

Role of interleukin 18 in acute lung inflammation induced by gut ischemia reperfusion.

AIM: To study the changes of endogenous interleukin 18 (IL-18) levels and evaluate the role of IL-18 on lung injury following gut ischemia/reperfusion. METHODS: A superior mesenteric artery occlusion model was selected for this research. The mice were randomly divided into four groups: Sham operation (sham), ischemia (0.5 h) followed by different times of reperfusion (I/R), and I/R pretreated with exogenous IL-18 (I/R+IL-18) or IL-18 neutralizing antibody (I/R+IL-18Ab) 15 min before ischemia. Serum IL-18 levels were detected by Western blot and ELISA, and the levels of IL-18 in lung tissue were evaluated by immunohistochemical staining. For the study of pulmonary inflammation, the lung myeloperoxidase (MPO) contents and morphological changes were evaluated. RESULTS: Gut ischemia/reperfusion induced rapid increase of serum IL-18 levels, peaked at 1 h after reperfusion and then declined. The levels of IL-18 in lung tissue were gradually enhanced as the progress of reperfusion. Compared with I/R group, exogenous administration of IL-18 (I/R+IL-18) further remarkably enhanced the pulmonary MPO activity and inflammatory cell infiltration, and in I/R+IL-18Ab group, the content of MPO were significantly reduced and lung inflammation was also decreased. CONCLUSION: Gut ischemia/reperfusion induces the increase of IL-18 expression, which may make IL-18 act as an important proinflammatory cytokine and contribute to gut ischemia/reperfusion-induced lung inflammation.

[Culture and comparison of the biological characteristics of human junctional epithelium and gingival epithelium].

PURPOSE: To study the different biological characteristics of human junctional epithelium (JE) and gingival epithelium (GE). METHODS: Human JE cells were cultured and identified by the cell culture and immunohistochemistry, and the biological characteristics of JE cells and GE cells were compared. RESULTS: The morphology of cultured JE cells was various and unequal, the arrangement of the cells was loose and mitosis was common, while GE colony was consisted of equal and closely packed epithelial-like cells in a paving stone arrangement. CK-Pan staining was positive in all JE and GE cells. CK19 was strongly stained in all JE cells but only moderately stained in some GE cells, and most GE cells were negative which was obviously different from JE cells. JE cells had longer latent period (7 days) than GE cells (4 days) during the cell growth period, and then the cells proliferated rapidly (4 days) to attain the maximum and descended rapidly in the declining period. While GE cells ascended evenly (7 days) to attain the maximum and descended slowly in the declining period. Proliferation study demonstrated the doubling time of JE cells was 48 to 60 hours and that of GE cells was 72 to 96 hours. It was possible to subculture JE cells up to 5 times serially, and that of GE cells was up to 7 times. CONCLUSIONS: The human JE cells are a kind of unique non-differentiated epithelial cells different from GE cells. In this experimental culture condition the subculture times of JE cells were less than GE cells, which affects JE cells, so the culture methods and conditions should be improved.

Characterization of the 3a protein of SARS-associated coronavirus in infected vero E6 cells and SARS patients.

Proteomics was used to identify a protein encoded by ORF 3a in a SARS-associated coronavirus (SARS-CoV). Immuno-blotting revealed that interchain disulfide bonds might be formed between this protein and the spike protein. ELISA indicated that sera from SARS patients have significant positive reactions with synthesized peptides derived from the 3a protein. These results are concordant with that of a spike protein-derived peptide. A tendency exists for co-mutation between the 3a protein and the spike protein of SARS-CoV isolates, suggesting that the function of the 3a protein correlates with the spike protein. Taken together, the 3a protein might be tightly correlated to the spike protein in the SARS-CoV functions. The 3a protein may serve as a new clinical marker or drug target for SARS treatment.