[Development and application syndromic surveillance and early warning system in border area in Yunnan Province]

Objective: To establish a dynamic syndromic surveillance system in the border areas of Yunnan Province based on information technology, evaluate its effectiveness and timeliness in the response to common communicable disease epidemics and improve the communicable disease prevention and control in border areas. Methods: Three border counties were selected for full coverage as study areas, and dynamic surveillance for 14 symptoms and 6 syndromes were conducted in medical institutions, the daily collection of information about students' school absence in primary schools and febrile illness in inbound people at border ports were conducted in these counties from January 2016 to February 2018 to establish an early warning system based on mobile phone and computer platform for a field experimental study. Results: With syndromes of rash, influenza-like illness and the numbers of primary school absence, the most common communicable disease events, such as hand foot and mouth disease, influenza and chickenpox, can be identified 1-5 days in advance by using EARS-3C and Kulldorff time-space scanning models with high sensitivity and specificity. The system is easy to use with strong security and feasibility. All the information and the warning alerts are released in the form of interactive charts and visual maps, which can facilitate the timely response. Conclusions: This system is highly effective and easy to operate in the detection of possible outbreaks of common communicable diseases in border areas in real time, so the timely and effective intervention can be conducted to reduce the risk of local and cross-border communicable disease outbreaks. It has practical application value.

Enhanced activity of NLRP3 inflammasome and its proinflammatory effect in influenza A viral pneumonia

Aim: The aim of this study was to investigate the activity of NLRP3 inflammasome and its effect on inducing severe pneumonia 1 week after influenza A virus (IAV) infection. Materials & methods: The expression levels of NLRP3, caspase-1 and IL-1β were assessed in murine macrophages stimulated with IAV. And the severity of viral pneumonia in mice was explored. Results & conclusion: The data showed that although the expression of NLRP3 diverged, activity of NLRP3 inflammasome was enhanced 1 week after IAV infection, and more severe viral pneumonia was associated with IL-1β in serum. It infers that enhanced activity of NLRP3 inflammasome induces augmented expression of IL-1β and severe pneumonia in a NLRP3-independent way, 1 week after IAV infection.

[Value of indocyanine green fluorescence tracer in laparoscopic cholecystectomy for acute cholecystitis]

Objective: To explore the value of low-dose indocyanine green (ICG) fluorescence imaging in laparoscopic cholecystectomy (LC) for acute cholecystitis. Methods: Clinical data of 198 patients with acute cholecystitis and had received LC in Changzhou No.2 People's Hospital from January 2020 to September 2021 were collected. In the fluorescence group (n=97), peripheral intravenous injection of ICG was performed 15 minutes before LC, while conventional white light was applied in the control group (n=101). The efficiency of bile duct discrimination, operation time, intraoperative bleeding and postoperative complications were compared between the two groups. Results: Of the 198 patients, 86 were males and 112 females. The differences were not statisticly significant in age [52 (44, 63) vs 56 (46, 68) years, P>0.05], history of chronic inflammation [34(35.1%) vs 31(30.7%) cases, P>0.05] and other clinical baseline data between the two groups. Compared with the control group, the fluorescence group had higher efficiency of bile duct identification [18 (16,19) vs 38 (28,55) min,P<0.001], shorter operation time [45 (40,60) vs 80 (65,100) min,P<0.001], less intraoperative bleeding [10 (5,15) vs 60 (20,100) ml,P<0.001], and less postoperative liver function damage [alanine aminotransferase 35.0 (23.4,51.0) vs 98.3 (67.0,134.8)U/L,P<0.001]. In the control group, there was one case of biliary duct injury during operation, one case of postoperative biliary fistula, and one case of postoperative hemorrhage. No similar adverse event was found in fluorescence group. Conclusions: ICG fluorescence imaging can improve the efficiency of LC for patients with acute cholecystitis. It is easy to operate and has a good clinical application value.

A case of chlamydia psittaci caused severe pneumonia and meningitis diagnosed by metagenome next-generation sequencing and clinical analysis: a case report and literature review

Background

Psittacosis, which is also known as parrot fever, is Chlamydia psittaci (C. psittaci) caused infectious disease. The clinical manifestations vary from asymptomatic infection to severe atypical pneumonia or even fatal meningitis. Early recognition of psittacosis is difficult because of its nonspecific clinical manifestations. Culture and gene probe techniques for C. psittaci are not available for routine clinical use, which makes the diagnosis difficult too. Although psittacosis has increasingly been recognized and reported in recent years, cure of severe pneumonia complicated with meningitis, with etiologic diagnosis aided by the use of metagenomic next-generation sequencing (mNGS), is still uncommon. So, it is necessary to report and review such potentially fatal case.

Case presentation

This report describes a 54-year-old woman with C. psittaci caused severe atypical pneumonia and meningitis. She presented with symptoms of fever, dry cough and dyspnea, accompanied by prominent headache. Her condition deteriorated rapidly to respiratory failure and lethargy under the treatment of empirical antibacterial agents, and was treated with invasive mechanical ventilation soon. She denied contact with birds, poultry or horses, but unbiased mNGS of both the bronchoalveolar lavage fluid (BALF) and the cerebrospinal fluid (CSF) identified sequence reads corresponding to C. psittaci infection, and there was no sequence read corresponding to other probable pathogens. Combined use of targeted antimicrobial agents of tetracyclines, macrolides and fluoroquinolones was carried out, and the patient’s condition improved and she was discharged home 28 days later. Her status returned close to premorbid condition on day 60 of follow-up.

Conclusions

When clinicians come across a patient with atypical pneumonia accompanied by symptoms of meningitis, psittacosis should be taken into consideration. mNGS is a promising detection method in such condition and is recommended.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-021-06205-5.

Aggravated MRSA pneumonia secondary to influenza A virus infection is derived from decreased expression of IL-1β

Secondary methicillin-resistant Staphylococcus aureus (MRSA) infection is a cause of severe pneumonia with high mortality during influenza A virus (IAV) pandemics. Alveolar macrophages (AMs) mount cellular defenses against IAV and MRSA infection, which occurs via the nucleotide-binding domain-like receptor protein 3 (NLRP3) inflammasome. However, the activity and function of the NLRP3 inflammasome in MRSA pneumonia secondary to IAV infection remain unclear. To clarify this, we studied MRSA infection secondary to IAV both in vitro and in mouse model. The expression of the NLRP3 inflammasome was evaluated by quantitative reverse transcription polymerase chain reaction, immunofluorescence, Western blot, and enzyme-linked immunosorbent assay. The lung pathology and the rate of weight change were observed. We found that IAV infection for 1 week activated NLRP3 inflammasome. The enhanced expression of NLRP3, caspase-1, and cleaved caspase-1 was associated with MRSA infection secondary to IAV, but the expression of interleukin (IL)-1β decreased in superinfection with MRSA both in vitro and in vivo. The aggravated inflammatory pathology in MRSA pneumonia secondary to IAV infection was associated with decreased expression of IL-1β. And increased weight loss in MRSA pneumonia secondary to IAV infection was related to decreased concentration of IL-1β in serum. It infers that superinfection with MRSA reduces expression of IL-1β someway, and decreased expression of IL-1β impairs the host immunity and leads to aggravated pneumonia. These results contributed to our understanding of the detailed activity of the NLRP3 inflammasome, IL-1β, and their relationship with aggravation of MRSA pneumonia secondary to IAV infection. Immunotherapy targeting the IL-1β signaling pathway could be possible therapeutic strategy for secondary MRSA pneumonia.

A combined approach using slightly acidic electrolyzed water and UV exposure to improve egg internal quality during storage

This study investigated the combined efficacy of slightly acidic electrolyzed water (SAEW) and UV light (UV) in improving egg internal quality (weight loss, Haugh unit, yolk index, albumen pH) over a 6-wk storage time at 25°C. Eggs were preserved after immersion for 4 min in SAEW (30 mg/L), irradiation for 4 min under a UV lamp, or a combination of SAEW and UV treatment for 4 min. The combination of SAEW and UV inhibited the deterioration of yolk index over the storage period, as well as reducing the extent of decrease in Haugh unit and of weight loss during storage at 25°C, and it was more effective than SAEW or UV alone in maintaining egg internal quality (P < 0.05). The results highlight the promising use of a SAEW and UV combination treatment to improve egg internal quality during storage.

A Case of Hemophagocytic Lymphohistiocytosis Secondary to Ralstonia Solanacearum Infection

BACKGROUND

Hemophagocytic lymphohistiocytosis (HLH), as known as Hemophagocytic syndrome (HPS), is deemed to a severe clinical syndrome caused by excessive human being immune system activation. Bacteria of Ralstonia genus is a non-fermentative, gram-negative bacillus and also in the category of human opportunistic pathogenic bacteria. In this article, authors report a rare case of Hemophagocytic lymophohistiocytosis which probably was triggered by Ralstonia solanacearum (R. solanacearum) infection.

METHODS

Hematologic investigation, biochemical examination, high throughput genetic test for infectious agents and bone marrow puncture.

RESULTS

The patient achieved complete remission and no signs of relapse have as yet been found.

CONCLUSIONS

The bacteria of Ralstonia genus merely infect humans, and there were no reports about the infection of R. solanacearum in humans and secondary HLH. The prognosis of the patient in this case was very good. This result, we think shows that the relationship between HLH and R. solanacearum infection should be taken into the diagnosis process. Recognition of this will promote the correct diagnosis in clinical work.

Meta-analysis of the association of IGFBP3 and IGF1 polymorphisms with susceptibility to colorectal cancer

The aim of this study is to comprehensively evaluate the associations of IGFBP3 and IGF1 polymorphisms with susceptibility to colorectal cancer (CRC). We searched the English and Chinese databases and recruited case-control studies based on strict inclusion and exclusion criteria. The statistical analysis was performed by the Comprehensive Meta-analysis 2.0 (CMA 2.0) software and this initially identified 251 studies. We then recruited 10 English studies to this meta-analysis detailed review which includes 9,415 CRC patients and 14,179 healthy controls. Our results demonstrated that IGFBP3 rs2854746 C>G polymorphism increases susceptibility to the CRC (allele model: OR=1.167, 95% CI=1.095~1.244, p<0.001 and to the dominant gene model: OR=1.226, 95% CI=1.113~1.350, p<0.001); but IGFBP3 rs2854744 A>C has no significant association with the CRC susceptibility (allele model: OR=0.970, 95% CI=0.932~1.010, p=0.138; dominant gene model: OR=0.995, 95% CI=0.936~1.057, p=0.874). Also, IGF1 rs35767 C>T polymorphism decreases susceptibility to CRC (allele model: OR=0.785, 95% CI=0.726~0.850, p<0.001 and also the dominant model: OR=0.730, 95% CI=0.661~0.806, p<0.001). However, IGFBP3 rs2854746 C>G is considered the susceptible CRC polymorphism and IGF1 rs35767 C>T is CRC protective.

Expression and effect of serum interleukin-24 level on bone marrow mononuclear cells in children with acute leukemia

To investigate the expression of interleukin-24 (IL-24) in the children with acute leukemia (AL) and its effect on the apoptosis of bone marrow mononuclear cells (BMMNCs) in vitro. Four groups were assessed: acute lymphocytic leukemia (ALL), acute myeloid leukemia (AML), non-leukemia, and healthy groups, 20 children in each group. ELISA was used to measure IL-24 serum level. The bone marrow was taken from patients and controls. BMMNCs were isolated and the DNA was analyzed by glucose electrophoresis. Flow cytometry was used to determine BMMNC apoptosis. The serum level of IL-24 in the ALL and AML groups were significantly higher than in the other two groups. There was no statistical difference between ALL and AML groups, either between non-leukemia and healthy groups. BMMNCs were exposed to IL-24 for 48 h, and the apoptotic rate of the group treated with 50 ng/ml IL-24 was obviously higher than that of control group (0 ng/mL). The serum IL-24 level of AL children decreased comparing to non-leukemia and healthy children, indicating that IL-24 can induce BMMNCs apoptosis of AL children in vitro.

Disseminated infection caused by Emmonsia pasteuriana in a renal transplant recipient

Emmonsia pasteuriana is a thermally dimorphic fungus identified in very few human cases. Here, we report a case of a 43-year-old male renal transplant patient from China presenting with multiple painful skin eruptions on his head, nose and left thigh, later accompanied by respiratory failure. Histopathology of the biopsy collected from the left thigh upper ulcer and occipital nodule both demonstrated chronic inflammation with granuloma formation and yeast-like elements. Emmonsia pasteuriana was cultured from two biopsy specimens and their identity was confirmed by sequencing of the rDNA internal transcribed spacer. The patient in intensive care showed marked clinical improvement with antifungal treatment.

Tumor-infiltrating lymphocytes predict response to chemotherapy in patients with advance non-small cell lung cancer

Accumulating preclinical evidence suggests that anticancer immune responses contribute to the success of chemotherapy. The predictive significance of tumor-infiltrating lymphocytes (TILs) for response to neoadjuvant chemotherapy in non-small cell lung cancer (NSCLC) remains unknown. The aim of this study was to investigate the prognostic and predictive value of TIL subtypes in patients with advanced NSCLC treated with platinum-based chemotherapy. In total, 159 patients with stage III and IV NSCLC were retrospectively enrolled. The prevalence of CD3(+), CD4(+), CD8(+) and Foxp3(+) TILs was assessed by immunohistochemistry in tumor tissue obtained before chemotherapy. The density of TILs subgroups was treated as dichotomous variables using the median values as cutoff. Survival curves were estimated by the Kaplan-Meier method, and differences in overall survival between groups were determined using the Log-rank test. Prognostic effects of TIL subsets density were evaluated by Cox regression analysis. The presence of CD3(+), CD4(+), CD8(+), and FOXP3(+) TILs was not correlated with any clinicopathological features. Neither the prevalence of TILs nor combined analysis displayed obvious prognostic performances for overall survival in Cox regression model. Instead, higher FOXP3(+)/CD8(+) ratio in tumor sites was an independent factor for poor response to platinum-based chemotherapy in overall cohort. These findings suggest that immunological CD8(+) and FOXP3(+)Tregs cell infiltrate within tumor environment is predictive of response to platinum-based neoadjuvant chemotherapy in advanced NSCLC patients. The understanding of the clinical relevance of the microenvironmental immunological milieu might provide an important clue for the design of novel strategies in cancer immunotherapy.

Effects of Bacillus subtilis KD1 on broiler intestinal flora

A novel Bacillus subtilis KD1 strain was isolated and identified from healthy broilers, and its phylogenetic classification was subsequently analyzed. To evaluate its probiotic availability, its growth characteristics and tolerance for the gut environment were evaluated in vitro. The results suggest that B. subtilis KD1 is superior in secreting neutral protease and is highly tolerant of gastric acid and bile salt. In the logarithmic growth phase, the neutral protease reached a maximum of 1,369.3 U/mL. When all live bacteria had become spores in the broth, B. subtilis KD1 was freeze dried and fed to broilers at 10(9), 5 × 10(9), and 10(10) bacilli/kg of feed. The animal trial results suggest that the addition of the new strain significantly improved intestinal flora by increasing lactobacilli and reducing Escherichia coli (P < 0.05) as compared with the control; hence, B. subtilis KD1 is a promising probiotic organism in broilers.

[Analysis of risk factors related to mortality of patients with community-acquired pneumonia due to methicillin-resistant Staphylococcus aureus]

OBJECTIVE

To describe the clinical features of reported cases of community-acquired pneumonia (CAP) due to methicillin-resistant Staphylococcus aureus (MRSA), and to evaluate the risk factors related to outcome.

METHODS

A systematic search of databases from January 1995 to December 2009 was performed. Baseline characteristics of survivors and non-survivors in the hospital were compared with the chi2 test for categorical variables. Variables with P<0.2 were entered in Logistic regression. Survival analysis was estimated by the Kaplan-Meier method according to use of antimicrobials inhibiting toxin production.

RESULTS

Fifty-two articles were identified reporting data on 74 patients, with 41.1% of total mortality, short duration of symptom onset to death [(6.1+/-11.0) days], and prolonged hospital admissions [(28.6+/-29.1) days]. Logistic regression analysis showed that influenza like symptoms (P=0.04), hemoptysis (P<0.01), leucopenia (P<0.01) were the risk factors associated with death, and using clindamycin or linezolid which could inhibit the Panton-Valentine leukocidin (PLV, P<0.01) was the factor associated with survival. Kaplan-Meier analysis indicated that the antibiotic therapies inhibiting toxin production were associated with improved outcome in these cases (chi2=21.59, P<0.01).

CONCLUSION

CAP due to MRSA is a severe disease with significant lethality. Empiric therapy of severe CAP with flu-like symptoms, hemoptysis and leucopenia should include coverage for MRSA. Targeted treatment with antimicrobials inhibiting toxin production appear to be more appropriate selection.

Effect of recombinant Panton–Valentine leukocidin in vitro on apoptosis and cytokine production of human alveolar macrophages

Panton–Valentine leukocidin (PVL) is associated with rare cases of necrotizing pneumonia that occur in otherwise healthy individuals. Human alveolar macrophages (HAMs) are major effector cells in host defense against infections. However, the impact of PVL on HAMs is uncertain. We evaluated the role of PVL in cytotoxicity and production of inflammatory cytokines secreted by HAMs. HAMs were purified from bronchoalveolar lavage fluid. Recombinant PVL (rPVL) was used in the study to interfere with HAM apoptosis and cytokine production in vitro. Hoechst 33342 fluorescence staining, transmission electron microscopy examination, and flow cytometry indicated that rPVL (10 nmol/L) treatment resulted in HAMs with markedly apoptotic characteristics, and HAMs treated with rPVL at 100 nmol/L showed clear indication of necrosis. A treatment of rPVL at 10 nmol/L elicited the secretion of IL-10 by HAMs relative to untreated control cells, but there was a slight decrease in the constitutive secretion of tumor necrosis factor (TNF)-α. Our results indicate that PVL-treated samples decreased HAM viability, leading to apoptosis at low concentrations and necrosis at high concentrations. In addition, PVL-treated cells released increased amounts of IL-10 and decreased amounts of TNF-α under apoptosis-inducing concentrations. Therefore, we speculated that PVL could play a negative role in HAM function at lower concentrations.

[Pulmonary nocardiosis in immunocompromised host: report of 2 cases and review of the literature]

OBJECTIVE

To investigate the clinical, imaging and pathogenic features of pulmonary nocardiosis and the drug resistance of Nocardia.

METHODS

The clinical and radiological data of 2 cases of pulmonary nocardiosis in this hospital were presented, and 32 cases reported in the Chinese literature since 1982 were reviewed.

RESULTS

Among the 34 cases of Nocardia infections, there were 26 cases of pulmonary nocardiosis, and 4 of whom died. Multiple organ infection occurred in 11 patients, including 7 with pulmonary and skin infections, 3 with pulmonary, skin and intracranial infections, and 1 with pulmonary and intracranial infections. All patients with pulmonary nocardiosis had cough. Of the 34 cases, 27 had fever, including intermittent fever in 5, and sustained fever in 22 cases. Of the 11 cases of pulmonary nocardiosis complicated with skin or intracranial dissemination, 8 patients were immunocompromised and 3 were immunocompetent (chi(2) = 2.08, P > 0.05). Three cases died in the immunocompromised group and 1 died in the immunocompetent group. Nocardia asteroides was identified in 14 cases, Nocardia brasiliensis in 4 cases, and the other 8 were not classified. In the patients with complicated skin or intracranial infections, 8 were caused by Nocardia asteroids, and 2 were caused by Nocardia brasiliensis. Chest X-ray or CT imaging of the lungs showed pleural effusion in 8, masses in 7, infiltrates in 6, cavities in 6, and nodular lesions in 5 cases. Antimicrobial susceptibility testing showed that Nocardia was sensitive to sulfonamide, amikacin, cefotaxime, ceftriaxone, minocycline, fluoroquinolones, and linezolid.

CONCLUSIONS

Immunosuppression is the most important predisposing factor for pulmonary nocardiosis. The most common pathogenic bacterium is Nocardia asteroids, which is frequently associated with disseminated lesions. The radiographic abnormalities of the lung show pleural effusion, masses, infiltration or cavity. With the increasing rate of resistance of Nocardia to the sulfonamide, the combination of antibiotic regimen according to susceptibility testing needs to be considered. Poor outcome is mostly found in immunocompromised hosts.

[The effect of recombinant panton-valentine leukocidin on the production of cytokines by human alveolar macrophages]

OBJECTIVE

To investigate the effect of recombinant panton-valentine leukocidin (rPVL) on the regulation of human alveolar macrophage CD14 and IL-10 and TNF-alpha.

METHODS

Human alveolar macrophages (AM) were purified and cultured from bronchoalveolar lavage fluid. Each sample was divided into groups according to different concentrations and exposure times of rPVL. Semi-quantitative RT-PCR was used to evaluate the CD14 mRNA levels and Double-antibody-sandwich-ELISA was used to measure the IL-10 and TNF-alpha levels in AM cultures.

RESULTS

CD14 mRNA decreased after rPVL treatment in time-and concentration dependent manners. There were no statistically significant differences in CD14 mRNA among the blank control groups (F = 1.708, P > 0.05). CD14 mRNA in the T6N10 group and the T6N100 group( T = time in hours, N = concentration of rPVL/nmol/L) decreased as compared to the T6N0 group (t = 4.132, 6.818, both P < 0.001), and that in the T24N10 group and the T24N100 group also decreased as compared to the T24N0 group (t = 7.401, 11.415, both P < 0.001), indicating that the expression of CD14 was downregulated by rPVL treatment. There were also statistically significant differences in CD14 mRNA between T6N10 and T24N10 groups, T6N100 and T24N100 groups (t = 4.692, 6.019, both P < 0.001), T6N10 and T6N100 groups, T24N10 and T24N100 groups (t = 2.686, 4.014, P < 0.01 respectively), indicating that the expression of CD14 decreased as the treatment time and the concentration of rPVL increased. The IL-10 concentrations of the T24N10 and T24N100 groups increased as compared to the T24N0 group (t = 4.036, 3.941, both P < 0.01) in time-dependent and concentration-dependent manners with rPVL treatment. The TNF-alpha concentration of the T24N10 group decreased while that of the T24N100 group increased as compared to the T24N0 group (t = 2. 824, 8. 468, both P < 0.01, respectively), indicating that a lower concentration of rPVL inhibited TNF-alpha release while a higher concentration of rPVL induced release of TNF-alpha.

CONCLUSION

The results suggest that rPVL could reduce the expression of CD14 and induce disordered release of anti-inflammatory and proinflammatory cytokines by AMs, which may be one of the important mechanisms underlying the high mortality of infection with PVL-positive Staphylococcus aureus.

Pulmonary cryptococcosis in non-AIDS patients

PURPOSE

To clarify the clinical features and imaging characteristics of non-AIDS patients with pulmonary cryptococcosis.

METHODS

We retrospectively collected 15 HIV-negative patients with pathology-proved pulmonary cryptococcosis from Sep 1992 to Jan 2008. Their medical records and radiological data were reviewed and analyzed.

RESULTS

Only one patient was asymptomatic.Thirteen patients were immunocompetent and two were immunosuppressed. Three patients had associated cryptococcosis meningitis. The most common radiographic abnormalities were multiple pulmonary nodules or masses, seen in 8 and 5 cases of patients respectively. 14 patients received specific therapy for Cryptococcus neoformans. Two patients died. In the 11 patients with isolated pulmonary cryptococcosis, treatment consisted of fluconazole alone (n=7), in combination with amphotericin B (n=2), and both 5-flucytosine and amphotericin B (n=2). For the other 2 patients with cryptococcosis meningitis, one was treated with amphotericin B alone and the other with fluconazole combined with amphotericin B and 5-flucytosine.

CONCLUSIONS

Non-AIDS patients might also susceptible to cryptococcosis infection. Histological examination is the principal method of diagnosis. The most common CT findings are solitary or multiple nodules with or without cavitation in the subpleural areas of the lung.

Chronic exposure to exogenous matrilysin induces chemoresistance and enhances Bcl-2 expression in A549 lung adenocarcinoma cells

Matrix metalloproteinase (MMP) family member matrilysin (matrilysin) has been indicated to induce apoptosis-resistance and chemoresistance. The purpose of current study was to investigate the potential capacity of induction cisplatin-resistance upon the unremitting exposure to exogenic matrilysin. At the same time, the expressions of apoptosis-related genes were examined to clarify the underlying mechanisms. A549 lung adenocarcinoma cells was used to establish our chronic exposure models. The viability of A549 lung adenocarcinoma cells was determinated by MTT and the apoptosis was assessed by Hoechst 33342 staining and Annexin V-FITC/PI apoptosis kit. The expressions of apoptosis-relative genes were evaluated by flow cytometry, immunocytochemistry staining and real-time quantitative RT-PCR, respectively. Overall, chronic exposure to crescenting level of exogenous matrilysin (10, 50, 100, 200 ng/ml) did not significantly alter the growth rates of A549 cells. However, a certain range of matrilysin might protect tumor cells from cisplatin-medicated death. The underlying mechanism may due to the Bcl-2 overexpression and imbalance in the ratio of Bcl-2/Bax. Our results offer a potential mechanism to explain the impact of matrilysin on apoptosis and provide new insights into the profound mechanisms of acquired cisplatin-resistance. Further researches are highly suggestive of this association which has great clinical implications.

Predictive value of MMP-7 expression for response to chemotherapy and survival in patients with non-small cell lung cancer

Fundamental studies have suggested that matrix metalloproteinases-7 (MMP-7) expression is associated with chemoresistance and constitutes a prognostic factor in several solid tumors. The present study assessed the prognostic and predictive value of MMP-7 in tumors of patients with advanced non-small cell lung cancer (NSCLC) treated with platinum-based chemotherapy. In total, 159 patients with stage III and IV NSCLC were retrospectively enrolled. Immunohistochemistry was performed to evaluate the expression of MMP-7, apoptosis-related proteins Bcl-2, Bax, Fas and FasL and the Ki-67 proliferation marker. The TUNEL (terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling) method was performed to investigate tumor apoptosis. Ninety carcinomas (56.6%) were identified as high expression of MMP-7. Overexpression of MMP-7 was more frequent in adenocarcinomas than in squamous cell carcinomas (P = 0.032). The expression of MMP-7 was positively related with Ki-67 index and Bcl-2, but not apoptosis index. MMP-7 status was correlated inversely with response to chemotherapy in overall patients (response rates, 20.0% and 35.8%, for patients with high-MMP-7 and low-MMP-7 tumors, respectively, P = 0.036), especially in adenocarcinoma (P = 0.021), but not in patients with squamous cell carcinomas (P = 0.373). The overall survival was significantly lower in NSCLC patients with high MMP-7 than in those with low MMP-7 (P < 0.001). A Cox regression analyses also demonstrated MMP-7 status to be a significant prognostic factor (hazard ratio, 5.49 P = 0.001). These findings suggest that the expression level of MMP-7 in tumor cells is predictive of response to chemotherapy and outcome in patients with advanced NSCLC receiving platinum-based chemotherapy.

Matrilysin inhibits proliferation and modulates sensitivity of lung cancer cells to FasL-mediated apoptosis

AIMS AND BACKGROUND

Matrix metalloproteinase (MMP) family member MMP-7 (matrilysin) cleaves various cell-surface proteins to alter their effector functions in addition to a broad substrate specificity against extracellular matrix components. Matrilysin expression is closely associated with the advanced clinicopathological stages and unfavorable prognosis. The current study tried to describe the comprehensive impacts of matrilysin on proliferation, and focused on its influence on the susceptibility to FasL-induced apoptosis in A549 lung adenocarcinoma cell line. We also detected the expressions of apoptosis-relative genes to further clarify the underlying mechanisms.

STUDY DESIGN

The viability of A549 cells was determined by MTT and the apoptosis was assessed by Hoechst 33342 staining and Annexin V-FITC/PI apoptosis kit. The expressions of apoptosis-relative genes were evaluated by flow cytometry, ELISA, and real-time quantitative RT-PCR, respectively.

RESULTS

Overall, matrilysin exhibited the inhibition of cell growth in a dose- and time-dependent manner by arresting in G0/G1 phase of the cell cycle and inducing apoptosis on A549 cells. Although it directly promoted apoptosis at high concentrations, a certain range of matrilysin might protect tumor cells from FasL-mediated death. The underlying mechanism may be due to the imbalance in the susceptibility of surface membrane-bound Fas receptor and ligand to proteolysis activity of matrilysin.

CONCLUSION

Our data indicated matrilysin may be multiple, multifarious, and multifaceted functions contributing to early tumor growth. A therapeutic key might be to modulate activity and function of matrilysin under diverse pathological conditions, but not completely eliminate the expression or function.

[Clinical analysis of community-acquired pneumonia in the elderly]

OBJECTIVES

To evaluate the clinical features, etiology, and outcome of patients over 65 years old hospitalized for community-acquired pneumonia (CAP).

METHODS

A retrospective cohort analysis was performed for adult patients hospitalized with CAP in a 1000-bed teaching hospital between Jan 2002 and Jan 2006. Differences between < or = 65 yrs and > 65 yrs groups were calculated using chi(2) test.

RESULTS

A total of 302 patients (166 males), with a mean age of (68 +/- 21) yrs, were enrolled. Of the 216 elderly patients, 67.1% had comorbid conditions, mostly cardiovascular diseases and chronic obstructive lung disease. For the risk stratification, 175 patients were classified as IV - V according to Fine's index. The mean hospital stay was 12 days and in-hospital mortality was 12.0%. The most frequent pathogen was Streptococcus pneumoniae in elderly patients. As compared to 86 younger patients (< or = 65yrs), altered mental status, dyspnea, tachypnea and tachycardia on hospital admission were more frequent in the elderly. The etiological distribution was also different between the two groups.

CONCLUSIONS

CAP in elderly patients is a prevalent disease with high incidence of complications and mortality. More attention should be paid to the specific clinical manifestations of this patient population.

An immunohistochemical and molecular study of gastrointestinal stromal tumours

Gastrointestinal stromal tumour (GIST) is a rare but most common mesenchymal tumour in the gastrointestinal tract. Although GIST research has been carried out extensively worldwide, it has yet to be studied in Malaysia. To establish the immunohistochemical expression pattern of CD117 (c-KIT), CD34, S-100 and Desmin, the incidence of c-KIT and PDGFRA genes mutation in GISTs, and correlate it with clinicopathological parameters. Eleven clinically diagnosed GISTs were stained for CD117, CD34, Desmin and S-100 protein by immunohistochemical technique, and c-KITand PDGFRA gene mutations were studied by PCR-CSGE-DNA sequencing method. All GISTs (7 cases) stain positive for CD117, and co-expressed CD34. None of these cases express Desmin, and only one expressed S-100 protein focally. Fifty-seven percent (4/7 cases) of GIST harboured mutations at exon 11 of c-KIT gene, and they were all high risk and malignant cases. No mutation was detected at exons 9, 13 and 17 of KIT gene, and exons 12 and 18 of PDGFRA gene. Immunohistochemistry using a panel of antibodies shows consistent pattern of CD117 and CD34 expression in GIST, and mutational study may be a useful prognostic marker for kinase inhibitor treatment of GIST.

[Study on the molecular mechanism of transferable multiple-antibiotic resistance in extended-spectrum beta-lactamase-producing clinical isolates]

OBJECTIVE

To investigate the molecular mechanism of transferable multiple-antibiotic resistance in extended-spectrum beta-lactamases (ESBLs) producing isolates.

METHODS

Antibiotics susceptibility was tested by E-test method, and multi-resistance plasmids were screened and isolated by extracting transformant plasmids. Inserted gene Cassettes of class 1 integron were amplified and analyzed by polymerase chain reaction (PCR) and DNA sequencing.

RESULTS

Eight of the nine ESBL-producing plasmids were found to comprise class 1 integron sequence, of them 7 harbored 1 or 2 antibiotic resistant gene cassettes which encoding resistance to aminoglycosides (aacA4, aadA2 or aadA5), trimethoprim (dhfrA12 or dfrA17), rifampicin (arr-3) and chloramphenicol (cmlA6). The function of these gene cassettes corresponded to the resistance profiles of their electro-transformants.

CONCLUSION

Multi-resistance gene cassettes located on plasmids and mediated by class 1 integron may play an important role in causing the development and dissemination of multiple-antibiotic resistance in ESBL-producing clinical isolates.

Expression of laminin in metastatic melanoma cell lines with different metastatic potential

Cancer metastasis is a complex multi-step process in which tumor cells leave the primary site and develop a secondary tumor in distant organs. Laminin plays an important role in this process. The expression of laminin in four melanoma cell lines with different metastatic potentials was investigated by immunohistochemistry, immunogold electron microscopy and Western blotting. Our results showed that the expression of endogenous laminin and the percentage of the positive cells are higher with increased metastatic potentials. It is, thus, suggested that endogenous laminin may contribute to the different metastatic properties in the melanoma cell line.

Association of EGFR gene fragments with nuclear matrix proteins in high and low metastatic melanoma cell lines

Two melanoma cell lines with different metastatic potential were used to study the association of EGFR gene fragments with the nuclear matrix and its role in cancer metastasis by polymerase chain reaction. A 940 bp positive amplification by PCR using primers I-II was demonstrated in a high metastatic cell line, WM451. A 110 bp positive amplification was shown using primers III-IV in both high and low metastatic cell lines. This finding demonstrates that EGFR gene fragments are tightly bound to the nuclear matrix and suggests that binding ability of this EGFR gene fragment to nuclear matrix seems to be closely related to metastatic potential in melanoma cell lines WM45 1 and WM35.

Expression of nm23-H1 in human meningioma cells

The expression of nm23-H1 has been demonstrated to be highly correlated with the metastatic potential of various tumors. In the present investigation, meningiomas of different pathological grades were used to study on their nm23-H1 expression. Immunohistochemistry showed that nm23-H1 was expressed mainly in the cytoplasm especially in the perinuclear region in explants under short-term culture. Western-blotting demonstrated the specific expression of nm23 protein in all tumor samples. The expression was also found to be sex-dependent on tumor progression in female, but not in male patients. RT-PCR results confirmed nm23-H1 expression was higher in benign tumors than in their normal counterpart. Our observations thus suggest that nm23-H1 may play an important role in the progression of meningiomas in female patients.

11-Oxo-tetrodotoxin and a specifically labelled 3H-tetrodotoxin

Tetrodotoxin was oxidized to a hydrated aldehyde, 11-oxo-tetrodotoxin, which shares the specificity of tetrodotoxin for the Na+ channel of the isolated voltage-clamped frog skeletal muscle fiber, but is four to five times more potent. It binds to the solubilized Na+ channel of eel electroplax with a similarly higher potency, because of an equilibrium dissociation constant about 0.25, and a dissociation rate constant 2.4 times slower than those for tetrodotoxin. 11-Oxo-tetrodotoxin can be reduced to regenerate a tetrodotoxin, which is chemically and biologically indistinguishable from the original tetrodotoxin. By reducing with tritiated sodium borohydride, a 3H marker can be inserted regiospecifically to yield 11-[3H]-tetrodotoxin. Because it has a defined specific activity of > 2.5 Ci/mmole, and a 3H marker which does not exchange with solvent proton, 11-[3H]-tetrodotoxin is an ideal tracer for tetrodotoxin. It may enable studies of problems which require higher signals and/or better stability of the marker than those obtainable from currently available tracer Na(+)-channel ligands.

Microwave-enhanced immunohistochemical staining of a formalin-sensitive antigen-laminin receptor

Many potentially useful antigens have been difficult to detect in formalin-fixed, paraffin-embedded tissues. Recently a number of pathological and research laboratories have demonstrated that some antigens masked by formalin fixation could be restored to detectability by microwave heating. Previously, we were unable to demonstrate laminin receptor in cells processed by the routine fixation. Our results showed that microwave heating together with trypsin produced the best immunohistochemical staining for this receptor. Nevertheless, no significance was found in the levels of 67 kD LR in high and low metastatic tumor cell lines.

[The expression of 67-KD laminin receptor (LN-R) gene in PG tumor cells with high metastatic potential]

The expression level of 67-KD LN-R mRNA was observed in high-metastatic PG tumor cells and low-metastatic PAa tumor cells based on the cDNA fragments of 67-KD LN-R amplified by PCR technique and the specific cDNA probe prepared by random primer labeling method. Results showed that the transcripts were homologous in size, about 1.7kb, in PG and PAa tumor cells. The 67-KD LN-R mRNA level was higher in PG than that in PAa tumor cells, and gene amplification was also more marked in PG tumor cells. After treated with 67-KD LN-R monoclonioal antibody (50, 100 and 400 micrograms/ml) for 48 hours, LN-R mRNA of PG tumor cells decreased significantly. It is suggested that 67-KD LN-R may play important roles in metastatic processes of PG tumor cells.

[Effects of metalloproteinases-1 (TIMP-1) cDNA transfection on biological behaviors of PG cells]

A recombinant plasmid, which contains a full length cDNA of human tissue inhibitor of metalloproteinases-1 (TIMP-1), was constructed by using gene recombinant technique, and introduced into a highly metastatic human giant cell carcinoma (PG) by lipofectin technique. Two of the transfectants, PG-T2 and PG-T4, were studied thoroughly. Northern blot showed an increased level of TIMP-1 mRNA in PG-T2 and PG-T4, compared with PG and PG-MV1 (vector-transfected control). The two transfectants also exhibited higher TIMP-1 protein activities. Moreover, they showed significant reduction in their proliferation rate and invasive abilities. The abilities of forming colonies in soft agar and tumorigenecity in athymic nude mice were abrogated in PG-T2 and PG-T4. The preliminary results suggest that a specific upregulation of TIMP-1 expression in metastatic cells could not only suppress their invasive and metastatic phenotype, but also inhibit their proliferation and tumorigenecity.

Differential growth regulation of a metastatic human lung carcinoma cell line through activation of phosphatidyl inositol turnover signal transduction pathway

Until recently, the signal transduction pathways involved in the processes of tumor growth have been poorly understood. In the present study, we investigated cell surface receptors which utilize phosphatidylinositol (Pl) turnover/Ca2+ mobilization as a signal transduction pathway to regulate cell growth in a metastatic human lung carcinoma cell line, PG. We found that purinoceptor agonists, including ATP and its analogs, and bombesin, an amphibian tetradeca-peptide of mammalian homology gastrin-releasing peptide, induced rapid transient increase of cytoplasmic-free Ca2+ in PG cells loaded with fura-2. The Ca2+ responses were derived both from release from internal stores and the opening of plasma membrane Ca2+ channels. HPLC analysis of inositol 1,4,5-triphosphate (Ins(1,4,5)P3) and its isomers showed a receptor-linked phospholipase C activation by ATP and bombesin. Although ATP and bombesin were both able to induce Pl turnover and Ca2+ mobilization in PG cells, they had differential growth regulatory effects on PG cells. Treatment with bombesin stimulated PG cell growth while treatment with ATP inhibited significantly PG cell growth. Pharmacological studies showed that the purinoceptors on PG cells were of the P2 subtype. Other hydrolysis-resistant P2 purinoceptor agonists, including ATP gamma S and AMP-PNP, were as effective as ATP in stimulating Pl turnover and Ca2+ mobilization as well as in inhibiting PG cell growth in vitro, suggesting the potential usefulness of such ATP analogs in clinical trials. Preliminary results suggest G protein involvement in the differential regulation of ATP and bombesin signal transduction pathways.

[Signal transduction study on the growth regulation of cells from human giant cell lung carcinoma in vitro]

The signal transduction involved in growth regulation of cells originally from a human giant cell lung carcinoma(PG) was investigated. The purinergic receptor agonists, ATP and its analogues, as well as bombesin all played a significant growth regulatory role on PG cells. ATP showed a growth inhibitory effect while bombesin showed a growth stimulatory effect on PG cells in vitro. Further investigation showed that ATP and bombesin activated phosphatidylinositol turnover/calcium mobilization signal transduction pathways in PG cells. and increased production of inositol-(1,4,5) trisphosphate and mobilization of intracellular free calcium, in which ATP and bombesin effects were dose-dependent. The purinergic receptor on PG cells was characterized by P2y subtype according to the order of PG cell responses to a series of ATP analogues. Pretreatment with cholera toxin showed different effects on the functions of ATP and bombesin, suggesting that the major difference between ATP and bombesin on signal transduction pathways may be at the G protein level.

Patterns of spatial dispersion, locomotion and foraging behaviour in three groups of the Yunnan snub-nosed langur (Rhinopithecus bieti)

Aspects of the behaviour of three groups of Yunnan snub-nosed langurs, Rhinopithecus bieti, were observed over the course of three field seasons from 1986 to 1988. The major findings of the study were: (1) The habitats of R. bieti were mainly at heights of 3,600-4,150 m above sea level. (2) Groups were very large, with group sizes ranging from more than 100 to 269 individuals. (3) Spatial dispersion densities ranged from about 27 to 106 m2/individual during sleeping and resting, to feeding dispersions as large as 5,000-15,000 m2. (4) The locomotor repertoire of R. bieti consisted largely of walking, jumping and climbing. On very rare occasions, semibrachiation was observed, but true brachiation was never observed. The locomotor repertoires of juveniles were more diverse than those of subadults or adults. (5) Communication consisted mainly of eye-to-eye contact accompanied by murmurs; while loud calls were heard only rarely. (6) Groups moved between sleeping and feeding sites in single file. It is concluded that R. bieti is a mainly terrestrial species.

[Cerebral infarction in 141 cases treated by traditional Chinese medicine and Western medicine]

Acute cerebral infarction of 141 cases with treatment combining TCM and WM was reported. The significant effective rate and the effective rate were 65% and 84% in the LT group (low molecular dextran + TCM) respectively; in the LN group (low molecular dextran + Nicotinic acid) were 29% and 41% respectively; in the T group (Salvia miltiorrhiza + Astragalus + Puraria) were 40% and 81.8% respectively. Among them the therapeutic effect in the LT group was the best. The LT group was also superior to the other two groups in serious cases. Cerebral edema developed following cerebrovascular dilator in a week after cerebral infarction; in the early stage, the therapeutic effect could be improved by giving mannitol first and then cerebrovascular dilator. Heart failure could be easily induced by low molecular dextran in the cerebral infarction following rheumatic heart disease. The therapeutic effect was poor in those cases with recurrent cerebral infarction.

[In vivo metastasis of human tumor transplant in T and NK cell immune-deficient mice]

Beige-nude mice with combined T and NK cell deficiency were produced by introducing "nu" gene into the beige mice of C57BL/6 background. The beige-nude mice were characterized by morphological features, level and activity of the NK cell in spleen and peripheral blood. NK cell level of the beige-nude mice was higher than the beige mice and similar to the ordinary nude mice though its NK cell activity was markedly lower than the nude mice. Human lung adenocarcinoma (PAa) was transplanted subcutaneously to the beige-nude mice and nude mice of BALB/cA background. No metastasis was found in BALB/cA nude mice (0/7), while in beige-nude mice, spontaneous lymph node metastasis rate was 36.3% (4/11). It should be noted that the transplanted PAa metastasized to lungs, which had never been seen in BALB/cA nude mice in previous experiments. The increase of metastatic rate is correlated with the relative low NK cell activity of the beige-nude mice. Our observation is that the beige-nude mice could be a suitable experimental model for in vivo study on metastatic behavior of the human tumors.

[Establishment of highly metastatic human tumor cell line in nude mice]

A total of 22 adult nude mice (7 approximately 17 weeks old) of BALB/cA origin were inoculated subcutaneously (SC) with human tumor cell lines derived from rhabdomyosarcoma and lung carcinomas, including squamous cell carcinoma, bronchiolo-alveolar carcinoma, small cell carcinoma, giant cell carcinoma and 2 types of adenocarcinoma. 12 neoplasms (54.5%) was confirmed at the initial transplantation and 7 serially transplantable tumors were established in 201 nude mice. Metastatic behavior of 7 human tumor cell lines grown in nude mice was judged histologically after sacrifice and SC transplanted tumors could either be highly metastatic (giant cell carcinoma), moderately metastatic (adenocarcinoma PAb), poorly metastatic (squamous cell carcinoma and adenocarcinoma PAa) or non-metastatic (small cell carcinoma and bronchiolo-alveolar carcinoma). The tumor from SC inoculated giant cell carcinoma (PG) could produce regional and/or distant lymph node metastases (12/12) and lung metastases (9/12) in BALB/cA nude mice maintained under semi-barrier system conditions. Six NIH nude mice developed metastatic tumor nodules both in the lymph node and lung (6/6) under the same condition. The highly metastasizing property of PG transplanted tumors remained after passage for as many as 18 times. The limitations of nude mice as an in vivo model for the study of tumor biology are discussed, eg. malignant neoplasms rarely metastasize when transplanted into nude mice. The use of such model (PG) could lead to a better understanding of the biology of metastasis, thus contributing to the development of new approaches to the therapy of metastasis.