Risk factors of multidrug-resistant bacteria infection in patients with ventilator-associated pneumonia: A systematic review and meta-analysis.

BACKGROUND: Multidrug-resistant (MDR) bacteria-induced VAP often has high lethality. We present this systematic review and meta-analysis to assess the risk factors for MDR bacterial infection in patients with VAP. METHODS: PubMed, EMBASE, Web of Science, and Cochrane Library were searched for studies regarding MDR bacterial infection in VAP patients, from Jan 1996 to Aug 2022. Study selection, data extraction, and quality assessment of included studies were conducted by two reviewers independently, and potential risk factors for MDR bacterial infection were identified. RESULTS: Meta-analysis showed that the score of the Acute Physiology and Chronic Health Evaluation II (APACHE-II) [OR = 1.009, 95% (CI 0.732, 1.287)], Simplified Acute Physiology Score II (SAPS-II) [OR = 2.805, 95%CI (0.854, 4.755)], length of hospital-stay before VAP onset (days) [OR = 2.639, 95%CI (0.387, 4.892)], in-ICU duration [OR = 3.958, 95%CI (0.894, 7.021)], Charlson index [OR = 1.000, 95%CI (0.889, 1.111)], overall hospital-stay [OR = 20.742, 95%CI (18.894, 22.591)], Medication of Quinolones [OR = 2.017, 95%CI (1.339, 3.038)], medication of carbapenems [OR = 3.527, 95%CI (2.476, 5.024)], combination of more than 2 prior antibiotics [OR = 3.181, 95%CI (2.102, 4.812)], and prior use of antibiotics [OR 2.971, 95%CI (2.001, 4.412)] were independent risk factors of MDR bacterial infection in VAP patients. Diabetes and mechanical ventilation duration before VAP onset showed no association with risk for MDR bacterial infection. CONCLUSIONS: This study has identified 10 risk factors associated with MDR bacterial infection in VAP patients. Identification of these factors would be able to facilitate the treatment and prevention of MDR bacterial infection in clinical practice.

Comparison of drug concentrations in blood and gastric lavage fluid before and after gastric lavage: A case report.

BACKGROUND: Gastric lavage (GL) is one of the most important early therapies to remove unabsorbed toxins from the gastrointestinal tract. However, the details of performing gastric lavage remain to be established. There is controversy in clinical practice regarding individual choice of the timing of GL and its efficiency. CASE SUMMARY: We report the case of a young woman who presented to the Emergency Department with drug intoxication for four hours. We used the latest toxicological screening techniques to compare drug concentrations in the patient's blood and gastric lavage fluid before and after gastric lavage. The results confirmed that gastric lavage was effective in reducing drug concentrations in the stomach; a small amount of drug remained in the stomach at the end of gastric lavage. CONCLUSION: Gastric lavage is effective in reducing drug concentrations in the stomach, with a small amount of drug remaining in the stomach at the end of gastric lavage.

Perioperative Risk Factors for Post-operative Pneumonia after Type A Acute Aortic Dissection Surgery.

OBJECTIVE: Type A acute aortic dissection (TAAAD) is a dangerous and complicated condition with a high death rate before hospital treatment. Patients who are fortunate to receive prompt surgical treatment still face high in-hospital mortality. A series of post-operative complications further affects the prognosis. Post-operative pneumonia (POP) also leads to great morbidity and mortality. This study aimed to identify the prevalence as well as the risk factors for POP in TAAAD patients and offer references for clinical decisions to further improve the prognosis of patients who survived the surgical procedure. METHODS: The study enrolled 89 TAAAD patients who underwent surgical treatment in Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei province, China from December 2020 to July 2021 and analyzed the perioperative data and outcomes of these patients. Logistic regression analyses were used to identify the risk factors for POP. RESULTS: In the study, 31.5% of patients developed POP. Patients with POP had higher proportions of severe oxygenation damage, pneumothorax, reintubation, tracheotomy, renal replacement therapy, arrhythmia, gastrointestinal bleeding, and longer duration of mechanical ventilation, fever, ICU stay, and length of stay (all with P<0.05). The in-hospital mortality was 2.3%. Smoking, preoperative white blood cells, and intraoperative transfusion were the independent risk factors for POP in TAAAD. CONCLUSION: Patients who underwent TAAAD surgery suffered poorer outcomes when they developed POP. Furthermore, patients with risk factors should be treated with caution.

Tuberculosis combined with Burkitt lymphoma in a kidney transplant recipient: A case report and literature review.

RATIONALE: Tuberculosis (TB) and post-transplant lymphoproliferative disorder are serious complications affecting the long-term survival of kidney transplant recipients (KTRs). Both of complications have overlapping clinical symptoms, signs, and high similar imaging presentation, which make early clinical diagnosis challenging. In this paper, we reported a rare case of post-transplant pulmonary TB combined with Burkitt lymphoma (BL) in KTR. PATIENT CONCERNS: A 20-year-old female KTR presented to our hospital with abdominal pain and multiple nodules throughout the body. DIAGNOSES: TB is diagnosed based on the lung histopathology showed fibrous connective tissue hyperplasia with number of chronic inflammatory changes, localized necrosis, granuloma formation and multinucleated giant cells were seen in the lung tissue. Moreover, lung histopathology specimen tested positive for TB gene. TB The culture for tuberculosis was positive. BL was diagnosed as metastatic after completion of liver and bone marrow biopsy. INTERVENTIONS: After an early diagnosis of TB, the patient received intensification of anti-tubercular therapy. Because the patient was diagnosed with BL, rituximab, cardioprotection, hepatoprotection and alkalinization of urine were added. OUTCOMES: After an early diagnosis of TB, the patient received anti-tubercular therapy and her clinical symptoms and imaging manifestations improved. After the diagnosis of BL was made, the patient's condition progressed rapidly, followed by multi-organ damage and died 3 months later. LESSONS: Therefore, in organ transplant patients, who present with multiple nodules and normal tumor markers, they should be alerted to the possibility of concurrent TB and post-transplant lymphoproliferative disorder, and perfect tests such as Epstein-Barr virus, ß2-microglobulin, lactate dehydrogenase, γ-interferon release test and Xpert Mycobacterium TB/rifampicin test and perform early lesion site biopsy to clarify the diagnosis with a view to improving the prognosis.

The Clinical Impact of Metagenomic Next-Generation Sequencing (mNGS) Test in Hospitalized Patients with Suspected Sepsis: A Multicenter Prospective Study.

Background: Metagenomic Next Generation Sequencing (mNGS) has the potential to detect pathogens rapidly. We aimed to assess the diagnostic performance of mNGS in hospitalized patients with suspected sepsis and evaluate its role in guiding antimicrobial therapy. Methods: A multicenter, prospective cohort study was performed. We enrolled patients with suspected sepsis, collected clinical characteristics and blood samples, and recorded the 30-day survival. Diagnostic efficacy of mNGS test and blood culture was compared, and the clinical impact of mNGS on antibiotic regimen modification was analyzed. Results: A total of 277 patients were enrolled, and 162 were diagnosed with sepsis. The mortality was 44.8% (121/270). The mNGS test exhibited shorter turn-out time (27.0 (26.0, 29.0) vs. 96.0 (72.0, 140.3) hours, p < 0.001) and higher sensitivity (90.5% vs. 36.0%, p < 0.001) compared with blood culture, especially for fungal infections. The mNGS test showed better performance for patients with mild symptoms, prior antibiotic use, and early stage of infection than blood culture, and was capable of guiding antibiotic regimen modification and improving prognosis. Higher reads of pathogens detected by mNGS were related to 30-day mortality (p = 0.002). Conclusions: Blood mNGS testing might be helpful for early etiological diagnosis of patients with suspected sepsis, guiding the antibiotic regimen modification and improving prognosis.

Effectiveness and safety of Liuhedan for treating cellulitis: A protocol for systematic review and meta-analysis.

BACKGROUND: Liuhedan is a famous traditional Chinese Medicine formula used to treat cellulitis in China. However, there are no systematic reviews for the evidence and the therapeutic effectiveness and safety of Liuhedan for treating cellulitis. The aim of this study is to summarize previous evidence, assessing the efficacy and safety of Liuhedan treating cellulitis. METHODS: We will search the EMBASE, WANFANG DATA, Web of Knowledge, CNKI, PubMed, ClinicalTrials.gov, and Cochrane Library from inception to June 30, 2021 to retrieve relevant studies using the search strategy: ("Liuhedan" OR "Liuhe Pill" OR "Liu-He-Dan") AND ("cellulitis" OR "phlegmon" OR "skin and soft tissue infection" OR "skin tissue infection" OR "soft tissue infection"). Two authors independently judged study eligibility and extracted data. Heterogeneity will be examined by computing the Q statistic and I2 statistic. RESULTS: This study assessed the efficiency and safety of Liuhedan for treating cellulitis. CONCLUSIONS: This study will provide reliable evidence-based evidence for the clinical application of Liuhedan for treating cellulitis. ETHICS AND DISSEMINATION: Ethical approval is unnecessary as this protocol is only for systematic review and does not involve privacy data. The findings of this study will be disseminated electronically through a peer-review publication or presented at a relevant conference.

Nasopharyngeal Swabs Are More Sensitive Than Oropharyngeal Swabs for COVID-19 Diagnosis and Monitoring the SARS-CoV-2 Load.

Objective: Detection of SARS-CoV-2 by oropharyngeal swabs (OPS) and nasopharyngeal swabs (NPS) is an essential method for coronavirus disease 2019 (COVID-19) management. It is not clear how detection rate, sensitivity, and the risk of exposure for medical providers differ in two sampling methods. Methods: In this prospective study, 120 paired NPS and OPS specimens were collected from 120 inpatients with confirmed COVID-19. SARS-CoV-2 nucleic acid in swabs were detected by real-time RT-PCR. The SARS-CoV-2 detection rate, sensitivity, and viral load were analyzed with regards NPS and OPS. Sampling discomfort reported by patients was evaluated. Results: The SARS-CoV-2 detection rate was significantly higher for NPS [46.7% (56/120)] than OPS [10.0% (12/120)] (P < 0.001). The sensitivity of NPS was also significantly higher than that of OPS (P < 0.001). At the time of sampling, the time of detectable SARS-CoV-2 had a longer median duration (25.0 vs. 20.5 days, respectively) and a longer maximum duration (41 vs. 39 days, respectively) in NPS than OPS. The mean cycle threshold (Ct) value of NPS (37.8, 95% CI: 37.0-38.6) was significantly lower than that of OPS (39.4, 95% CI: 38.9-39.8) by 1.6 (95% CI 1.0-2.2, P < 0.001), indicating that the SARS-CoV-2 load was significantly higher in NPS specimens than OPS. Patient discomfort was low in both sampling methods. During NPS sampling, patients were significantly less likely to have nausea and vomit. Conclusions: NPS had significantly higher SARS-CoV-2 detection rate, sensitivity, and viral load than OPS. NPS could reduce droplets production during swabs. NPS should be recommended for diagnosing COVID-19 and monitoring SARS-CoV-2 load. Chinese Clinical Trial Registry, number: ChiCTR2000029883.

Effect and mechanism of total saponin of Dioscorea on animal experimental hyperuricemia.

In this study, we investigated the effects and mechanisms of Total Saponin of Dioscorea (TSD) on animal experimental hyperuricemia. Mouse and rat hyperuricemic models were made by orally administering yeast extract paste once a day (30 and 20 g/kg, respectively), for 7 days. Yeast would disturb normal purine metabolism by increasing xanthine oxidase (XOD) activity and generating large quantities of uric acid. This model is similar to human hyperuricemia, which is induced by high-protein diets, due to a purine and nucleic acid metabolic disturbance. Another mouse hyperuricemia model was generated by intraperitoneal injection once with uric acid 250 mg/kg or potassium oxonate 300 mg/kg. Potassium oxonate, a urate oxidase inhibitor, can raise the serum uric acid level by inhibiting the decomposition of uric acid. Likewise, injecting uric acid can also increase serum uric acid concentration. The concentration of uric acid in serum or urine was detected by the phosphotungstic acid method, and the activity of XOD was assayed by a test kit. The results showed that TSD (240, 120 and 60 mg/kg, ig) could significantly lower the level of serum uric acid in hyperuricemic mice. TSD (120 and 60 mg/kg, ig) could also lower the level of serum uric acid in hyperuricemic rats, reduce the activity of XOD in the serum and liver of hyperuricemic rats, and increase the level of urine uric acid concentration as well as 24-hour total uric acid excretion. In conclusion, TSD possesses a potent anti-hyperuricemic effect on hyperuricemic animals, and the mechanism may be relevant in accelerating the excretion and decreasing the production of uric acid.

[Pharmacokinetic characteristics of ferulic acid in patients with different syndromes of deficiency of spleen qi, stagnation of liver qi and spleen deficiency, and excess of stomach heat].

OBJECTIVE: To investigate the nature of syndrome of traditional Chinese medicine by means of pharmacokinetic (PK) method. METHODS: Twenty-one healthy volunteers, 20 patients with syndrome of stagnation of liver qi and spleen deficiency, 22 patients with syndrome of deficiency of spleen qi and 19 patients with syndrome of excess of stomach heat were included and administered to take Jiawei Xiaoyaosan Recipe (JWXYSR). The serum PK parameters of ferulic acid (FA) were examined by high performance liquid chromatography (HPLC) method. RESULTS: The absorption rate constant (alpha) and the elimination rate constant (beta) were both decreased while the apparent first-order absorption constant (K(a)) was enhanced significantly in the patients with syndrome of deficiency of spleen qi; the alpha, beta and Ka were all reduced in the patients with syndrome of stagnation of liver qi and spleen deficiency; the beta and K(a) were increased in the patients with syndrome of excess of stomach heat, as compared with the corresponding PK parameters in the healthy volunteers (P<0.01). CONCLUSION: The PK analysis of FA in the patients with syndrome of deficiency of spleen qi shows that the absorption rate is accelerated, and both the distribution and elimination rates are slowed down. The absorption, distribution and elimination rates of AF are all slowed down in the patients with syndrome of stagnation of liver-qi and spleen deficiency, while the absorption and elimination rates of AF are both accelerated in the patients with syndrome of excess of stomach heat. There are obvious differences in the PK characteristics among these three syndromes.

Melatonin ameliorates carbon tetrachloride-induced hepatic fibrogenesis in rats via inhibition of oxidative stress.

Melatonin is reported to exhibit a wide variety of biological effects, including antioxidant and anti-inflammatory. Evidence shows the important role of oxidative stress in the etiopathogenesis of hepatic fibrosis. The aim of this study was to investigate the protective effects of administration of melatonin in rats with carbon tetrachloride-induced fibrosis for 6 weeks. Hepatic fibrotic changes were evaluated biochemically by measuring tissue hydroxyproline levels and histopathogical examinations. Malondialdehyde (MDA), an end product of lipid peroxidation, and glutathione peroxidase (GSH-px) and superoxide dismutase (SOD) levels were evaluated in tissue homogenates by spectrophotometry. The nuclear factor-kappaB (NF-kappaB) in liver tissue was examined by immunohistochemistry. Tumor necrosis factor-alpha (TNF-alpha) and interleukin-1beta (IL-1beta) concentrations in Kupffer cells (KCs) culture supernatants were measured with ELISA. The rats injected subcutaneously with CCl4 for 6 weeks resulted in hepatic fibrotic changes increased hydroxyproline and MDA levels, and decreased GSH-px and SOD levels, whereas melatonin reversed these effects. Furthermore, melatonin inhibited the expression of NF-kappaB in liver tissue and decreasing production of proinflammatory cytokines such as TNF-alpha and IL-1beta from KCs in fibrotic rats. These present results suggest that melatonin ameliorates carbon tetrachloride-induced hepatic fibrogenesis in rats via inhibition of oxidative stress and proinflammatory cytokines production.

Anti-hepatocarcinoma effects of 5-fluorouracil encapsulated by galactosylceramide liposomes in vivo and in vitro.

AIM: To study the anti-hepatocarcinoma effects of 5-fluorouracil (5-Fu) encapsulated by galactosylceramide liposomes (5-Fu-GCL) in vivo and in vitro. METHODS: Tumor-bearing animal model and HepA cell line were respectively adopted to evaluate the anti-tumor effects of 5-Fu-GCL in vivo and in vitro. Tumor cell growth inhibition effects of 5-Fu-GCL in vitro were assessed by cell viability assay and MTT assay. In vivo experiment, the inhibitory effects on tumor growth were evaluated by tumor inhibition rate and animal survival days. High performance liquid chromatography was used to detect the concentration-time course of 5-Fu-GCL in intracellular fluid in vitro and the distribution of 5-Fu-GCL in liver tumor tissues in vivo. Apoptosis and cell cycle of tumor cells were demonstrated by flow cytometry. RESULTS: In vitro experiment, 5-Fu-GCL (6.25-100 micromol/L) and free 5-Fu significantly inhibited HepA cell growth. Furthermore, IC50 of 5-Fu-GCL (34.5 micromol/L) was lower than that of free 5-Fu (51.2 micromol/L). In vivo experiment, 5-Fu-GCL (20, 40, 80 mg/kg) significantly suppressed the tumor growth in HepA bearing mice model. Compared with free 5-Fu, the area under curve of 5-Fu-GCL in intracellular fluid increased 2.6 times. Similarly, the distribution of 5-Fu-GCL in liver tumor tissues was significantly higher than that of free 5-Fu. After being treated with 5-Fu-GCL, the apoptotic rate and the proportion of HepA cells in the S phase increased, while the proportion in the G0/G1 and G2/M phases decreased. CONCLUSION: 5-Fu-GCL appears to have anti-hepato-carcinoma effects and its drug action is better than free 5-Fu. Its mechanism is partly related to increased drug concentrations in intracellular fluid and liver tumor tissues, enhanced tumor cell apoptotic rate and arrest of cell cycle in S phase.

Effects of total glucosides of peony on immunological hepatic fibrosis in rats.

AIM: To study the effects of total glucosides of peony (TGP) on immunological hepatic fibrosis induced by human albumin in rats. METHODS: Sixty adult male Sprague-Dawley rats were randomly divided into: Normal group, model group, TGP (60 and 120 mg/kg) treatment groups and colchicines (0.1 mg/kg) treatment group. On the day before the rats were killed, those in TGP or colchicine groups received TGP or colchicine as above from the first day of tail vein injection of human albumin. The rats in normal and model groups were only administered with the same volume of vehicle. At the end of the 16th wk, rats in each group were killed. Blood and tissue specimens were taken. Levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), nitric oxide (NO), content of malondialdehyde (MDA), activity of superoxide dismutase (SOD) and glutathione peroxidase (GSH-px), were measured by biochemical methods. Serum procollagen type III (PC III) and laminin (LN) were determined by radioimmunoassay. Liver collagen level was determined by measuring hydroxyproline content in fresh liver samples. Hepatic tissue sections were stained with hematoxylin-eosin and examined under a light microscope. RESULTS: Histological results showed that TGP improved the human albumin-induced alterations in the liver structure, alleviated lobular necrosis and significantly lowered collagen content. The antifibrotic effect of TGP was also confirmed by decreased serum content of LN and PCIII in TGP-treated group. Moreover, the treatment with TGP effectively reduced the hydroxyproline content in liver homogenates. However, the level of ALT and AST increased in fibrotic rat but had no significance compared with normal control, whereas the ratio of A/G decreased without significance. TGP had no effect on level of ALT, AST and the ratio of A/G. Furthermore, TGP treatment significantly blocked the increase in MDA and NO, associated with a partial elevation in liver total antioxidant capacity including SOD and GSH-px. CONCLUSION: TGP has beneficial effects on hepatic fibrosis in rats by inhibition of collagen synthesis and decreasing oxidative stress.

CXCL12 G801A polymorphism and cancer risk: An updated meta-analysis.

Many studies have reported the relationship between CXCL12 G801A polymorphism and cancer risk, with conflicting results. In this study, we tried to clarify the possibility that this polymorphism may increase cancer risk by conducting an updated meta-analysis. PubMed and EMbase were searched for case-control studies regarding the association of the gene polymorphism and cancer risk. Data were extracted and odds ratios (ORs) with 95% confidence intervals (95% CIs) were used to assess the strength of the association. Heterogeneity among articles and publication bias was also assessed. Significantly increased risk for cancer was found (A vs. G: OR=1.26, 95% CI=1.13-1.40, P<0.01; AA+AG vs. GG: OR=1.33, 95% CI=1.16-1.52, P<0.01). In subgroup analysis, statistically elevated cancer risk was found in both Asian and Caucasian populations (for Asian, AA+AG vs. GG: OR=1.74, 95% CI=1.22-2.47, P<0.01; for Caucasian, AA+AG vs. GG: OR=1.24, 95% CI=1.09-1.42, P<0.01). Our result indicated that CXCL12 G801A polymorphism is a risk factor for cancer. To validate the finding, further large-size case-control studies are warranted.

Leflunomide attenuates hepatocyte injury by inhibiting Kupffer cells.

AIM: To investigate the importance of direct contact between Kupffer cells (KCs) and hepatocytes (HCs) during hepatic inflammatory responses, and the effect of leflunomide's active metabolite, A(771726), on cytokines in KCs, HCs and KC cocultures (DC cocultures). METHODS: KCs and HCs in liver were isolated by digestion with pronase and collagenase. Lipopolysaccharide (LPS)-induced inflammatory response in monocultures of rat HCs and KCs was compared with that in DC cocultures. Tumor necrosis factor-alpha (TNF-alpha) and interleukin-1 (IL-1) concentrations in different culture supernatants were measured with ELISA. TNF-alpha mRNA in KCs of inflammatory liver injury was analyzed with reverse transcriptase polymerase chain reaction (RT-PCR). RESULTS: DC cocultures strongly exhibited the production of TNF-alpha and IL-1 compared with other cultures, and these cytokines were mainly produced by KCs, especially by activated KCs. Time course studies revealed an increased production of TNF-alpha preceding the IL-1 production, suggesting that increased TNF-alpha levels could be involved in the increase of IL-1 production. Leflunomide's active metabolite, A(771726), had significantly inhibitory effect on TNF-alpha and IL-1 at protein and transcription levels, and the reduced production of IL-1 by A(771726) was associated with the inhibitory action of A(771726 ) on TNF-alpha. CONCLUSION: Leflunomide can inhibit hepatocyte damage by inhibiting proinflammatory cytokine release from KCs.

Effect of leflunomide on immunological liver injury in mice.

AIM: To study the effect of leflunomide on immunological liver injury (ILI) in mice. METHODS: ILI was induced by tail vein injection of 2.5 mg Bacillus Calmette-Guerin (BCG), and 10 d later with 10 microg lipopolysaccharide (LPS) in 0.2 mL saline (BCG+LPS). The alanine aminotransferase (ALT), aspartate aminotransferase (AST), nitric oxide (NO) level in plasma and molondiadehyde (MDA), glutathione peroxidase (GSHpx) in liver homogenate were assayed by spectroscopy. The serum content of tumor necrosis factors-alpha (TNF-alpha) was determined by ELISA. Interleukin-1 (IL-1), interleukin-2 (IL-2) and Concanavalin A (ConA)-induced splenocyte proliferation response were determined by methods of (3)H-infiltrated cell proliferation. RESULTS: Leflunomide (4, 12, 36 mg.kg(-1)) was found to significantly decrease the serum transaminase (ALT, AST) activity and MDA content in liver homogenate, and improve reduced GSHpx level of liver homogenate. Leflunomide (4, 12, 36 mg.kg(-1)) significantly lowered TNF-alpha and NO level in serum, and IL-1 produced by intraperitoneal macrophages(PMphi). Moreover, the decreased IL-2 production and ConA-induced splenocyte proliferation response were further inhibited. CONCLUSION: These findings suggested that leflunomide had significant protective action on ILI in mice.

Protective effect of melatonin against liver injury in mice induced by Bacillus Calmette-Guerin plus lipopolysaccharide.

AIM: To investigate the effects and mechanisms of melatonin on immunological liver injury in mice. METHODS: A model of liver injury was induced by tail vein injection of Bacillus Calmette Guerin (BCG) and lipopolysaccharide (LPS) in mice. Kupffer cells and hepatocytes were isolated and cultured according to a modified two-step collagenase perfusion technique. Levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST) and nitric oxide (NO), content of malondiadehyde (MDA), activity of superoxide dismutase (SOD), were measured by biochemical methods. Tumor necrosis factor-alpha (TNF-alpha) activity was determined by RIA. Interleukin (IL)-1 activity was measured by thymocyte proliferation bioassay. Hepatic tissue sections were stained with hematoxylin and eosin and examined under a light microscope. RESULTS: Immunological liver injury induced by BCG+LPS was successfully duplicated. Serum transaminase (ALT, AST) activities were significantly decreased by melatonin (0.25, 1.0, 4.0 mg/kg bm). Meanwhile, MDA content was decreased and SOD in liver homogenates was upregulated. Furthermore, pro-inflammatory mediators (TNF-alpha, IL-1, NO) in serum and liver homogenates were significantly reduced by melatonin. Histological examination demonstrated that melatonin could attenuate the area and extent of necrosis, reduce the immigration of inflammatory cells. In in vitro experiment, TNF-alpha was inhibited at the concentrations of 10(-8)-10(-6) mol/L of melatonin, while IL-1 production of Kupffer cells induced by LPS (5 microg/mL) was decreased only at the concentration of 10(-6) mol/L of melatonin, but no effect on NO production was observed. Immunological liver injury model in vitro was established by incubating hepatocytes with BCG- and LPS-induced Kupffer cells. Activities of ALT, TNF-alpha, IL-1, and MDA in supernatant were significantly increased. Melatonin had little effect on the level of ALT, but reduced the content of TNF-alpha and MDA at concentrations of 10(-7)-10(-5) mol/L and decreased the content of IL-1 at concentrations of 10(-6)-10(-5) mol/L. CONCLUSION: Melatonin could significantly protect liver injury in mice, which was related to free radical scavenging, increased SOD activity and pro-inflammatory mediators.

A 771726, the active metabolite of leflunomide, inhibits TNF-alpha and IL-1 from Kupffer cells.

This study was conducted to investigate the importance of direct contact between Kupffer cells (KCs) and hepatocytes (HCs) during the hepatic inflammatory responses, and the effect of leflunomide's active metabolite, A771726, on cytokines in KCs and HCs (DC cocultures) and KC cultures using an in vitro approach. Lipopolysaccharide (LPS)-induced inflammatory response in monocultures of rats HCs and KCs were compared with DC cocultures. Tumor necrosis factor-alpha (TNF-alpha) and interleukin-1 (IL-1) concentrations of different culture supernatants were measured with ELISA. TNF-alpha and IL-1 mRNA in KCs of inflammatory liver injury was analyzed with reverse transcription polymerase chain reaction (RT-PCR). Our data showed that DC cocultures exhibited the highest production of TNF-alpha and IL-1 compared with other cultures, and these cytokines were mainly produced by KCs, in particular activated KCs. Time course studies revealed an increased production of TNF-a preceding the IL-1 production, suggesting that increased TNF-alpha levels could be involved in the increased IL-1 production. Leflunomide's active metabolite, A771726, has significantly inhibitory effect on TNF-a and IL-1 at protein and transcription levels, and reduced production of IL-1 by A771726 was associated with inhibitory action of A771726 on TNF-alpha. These results provided evidence that leflunomide significantly inhibited TNF-alpha and IL-1 from KCs.

Contribution of protein kinase C to passively sensitized human airway smooth muscle cells proliferation.

BACKGROUND: Airway smooth muscle proliferation plays an important role in airway remodeling in asthma. But little is known about the intracellular signal pathway in the airway smooth muscle cell proliferation in asthma. The objective of this paper is to investigate the contribution of protein kinase C (PKC) and its alpha isoform to passively sensitized human airway smooth muscle cells (HASMCs) proliferation. METHODS: HASMCs in culture were passively sensitized with 10% serum from asthmatic patients, with non-asthmatic human serum treated HASMCs used as the control. The proliferation of HASMCs was examined by cell cycle analysis, 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyltetrazoliumbromide (MTT) colorimetric assay and proliferating cell nuclear antigen (PCNA) immunofluorescence staining. The effect of PKC agonist phorbol 12-myristate 13-acetate (PMA) and PKC inhibitor Ro-31-8220 on the proliferation of HASMCs exposed to human asthmatic serum and non-asthmatic control serum was also examined by the same methods. The protein and mRNA expression of PKC-alpha in passively sensitized HASMCs were detected by immunofluorescence staining and reverse transcription-polymerase chain reaction. RESULTS: The percentage of S phase, absorbance (value A) and the positive percentage of PCNA protein expression in HASMCs passively sensitized with asthmatic serum were (16.30 +/- 2.68)%, 0.430 +/- 0.060 and (63.4 +/- 7.4)% respectively, which were significantly increased compared with HASMCs treated with control serum [(10.01 +/- 1.38)%, 0.328 +/- 0.034 and (37.2 +/- 4.8)%, respectively] (P < 0.05). After HASMCs were passively sensitized with asthmatic serum, they were treated with PMA, the percentage of S phase, value A and the positive percentage of PCNA protein expression were (20.33 +/- 3.39)%, 0.542 +/- 0.065 and (76.0 +/- 8.7)% respectively, which were significantly increased compared with asthmatic serum sensitized HASMCs without PMA(P < 0.05). After HASMCs passively sensitized with asthmatic serum were treated with Ro-31-8220, the percentage of S phase, value A and the positive percentage of PCNA protein expression were (11.21 +/- 1.56)%, 0.331 +/- 0.047 and (38.8 +/- 6.0)% respectively, which were significantly decreased compared with asthmatic serum sensitized HASMCs without Ro-31-8220 (P < 0.05). The relative ratio of value A of PKC-alpha mRNA and the positive percentage of PKC-alpha protein expression in passively sensitized HASMCs were 1.23 +/- 0.10 and (61.1 +/- 9.4)% respectively, which were significantly increased compared with HASMCs treated with control serum [1.05 +/- 0.09 and (34.9 +/- 6.7)%, respectively] (P < 0.05). CONCLUSIONS: The proliferation of HASMCs passively sensitized with human asthmatic serum is increased. PKC and its alpha isoform may contribute to this proliferation.

[Effect of nuclear factor-kappaB on signal transduction of passively sensitized human airway smooth muscle cells proliferation].

OBJECTIVE: To investigate whether nuclear factor-kappaB (NF-kappaB) contributes to passively sensitized human airway smooth muscle cell (HASMCs) proliferation, and whether it is the downstream factor of activated protein kinase C (PKC). METHODS: HASMCs in culture were passively sensitized with 10% serum from asthmatic patients, with non-asthmatic human serum treated HASMCs as the control. NF-kappaB specific inhibitor pyrrolidine dithiocarbamate (PDTC) and PKC agonist phorbol 12-myristate 13-acetate (PMA) were used to intervene HASMCs exposed to asthmatic serum and non-asthmatic control serum. The proliferation of HASMCs was examined by cell cycle analysis, MTT colorimetric assay and proliferating cell nuclear antigen (PCNA) immunofluorescence staining respectively. NF-kappaB activity was detected by NF-kappaBp65 immunofluorescence staining and electrophoretic mobility shift assay (EMSA) respectively. RESULTS: (1) The percentage of S phase, A value, the positive expression rate of PCNA, the positive expression rate of NF-kappaBp65 and EMSA value in HASMCs passively sensitized with asthmatic serum were (21.78 +/- 2.79)%, 0.466 +/- 0.058, (67.5 +/- 8.5)%, (12.6 +/- 2.2)% and 32 781 +/- 9499 respectively. They were significantly increased compared with those of the control serum group (P < 0.05). After previously treated with PDTC, the above figures were decreased to (16.37 +/- 3.05)%, 0.389 +/- 0.035, (53.4 +/- 5.1)%, (4.9 +/- 1.3)% and 3934 +/- 937 respectively (P < 0.05). (2) After HASMCs were treated with both PMA and asthmatic serum, the percentage of S phase, A value, the positive expression rate of PCNA, the positive expression rate of NF-kappaBp65 and EMSA value were (25.52 +/- 3.38)%, 0.572 +/- 0.054, (81.2 +/- 10.2)%, (26.5 +/- 5.0)% and 71 654 +/- 12 293 respectively. After previously treated with PDTC, the above figures were (16.42 +/- 2.72)%, 0.386 +/- 0.031, (54.2 +/- 5.3)%, (5.9 +/- 1.4)% and 4808 +/- 1084 respectively. The difference was significant (P < 0.05). CONCLUSIONS: NF-kappaB may contribute to the proliferation of HASMCs passively sensitized with human asthmatic serum, which involves the PKC/NF-kappaB signal pathway.

[The active metabolite of leflunomide A771726 inhibits proliferation and collagen synthesis of hepatic stellate cell].

OBJECTIVE: To investigate the effect of the metabolite of leflunomide, A771726,on proliferation and collagen synthesis of hepatic stellate cell (HSC). METHODS: HSC and Kupffer cells were isolated from the rat liver by collagenase IV and pronase perfusion, and purified by density gradient separation. The effects of A771726 on cell proliferation and collagen synthesis were examined by 3H-thymidine and 3H-proline incorporation assays, respectively. The TGF-beta, TNF-alpha and IL-1 levels in Kupffer cell conditioned medium (KCCM) were determined by enzyme-linked immunosorbent assay (ELISA). RESULTS: HSC and Kupffer cells in rat liver were well separated. The KCCM of CCl4-injured rats had significant stimulation effect on proliferation and collagen synthesis of HSC in primary culture. Addition of A771726 (0.001-10 micromol/Lein HSC culture stimulated by KCCM significantly inhibited proliferation and collagen synthesis of HSC. Furthermore, the elevated TGF-beta, TNF-alpha and IL-1 levels in KCCM of CCl4-injured rats were significantly reduced in A771726 treatment groups. CONCLUSION: A771726 has markedly inhibitory effect on proliferation and collagen synthesis of HSC and secretion of TGF-beta,TNF-alpha and IL-1 from Kupffer cells.