Selective α-oxidation of amides via visible-light-driven iron catalysis.

Hydroxyl radicals (˙OH) as one of the highly reactive species can react unselectively with a wide range of chemicals. The ˙OH radicals are typically generated under harsh conditions. Herein, we report hydroxyl radical-induced selective N-α C(sp3)-H bond oxidation of amides under greener and mild conditions via an Fe(NO3)3·9H2O catalyst inner sphere pathway upon irradiation with a 30 W blue LED light strip (λ = 455 nm) using NaBrO3 as the oxidant. This protocol exhibited high chemoselectivity and excellent functional group tolerance. A preliminary mechanism investigation demonstrated that the iron catalyst afforded hydroxyl radicals via the visible-light-induced homolysis (VLIH) of iron complexes followed by a hydrogen atom transfer (HAT) process to realize this transformation.

Emperipolesis mediated by CD8+ T cells correlates with biliary epithelia cell injury in primary biliary cholangitis.

Primary biliary cholangitis (PBC) is an autoimmune disease characterized by chronic destruction of the bile ducts. A major unanswered question regarding the pathogenesis of PBC is the precise mechanisms of small bile duct injury. Emperipolesis is one of cell-in-cell structures that is a potential histological hallmark associated with chronic hepatitis B. This study aimed to clarify the pathogenesis and characteristics of emperipolesis in PBC liver injury. Sixty-six PBC patients, diagnosed by liver biopsy combined with laboratory test, were divided into early-stage PBC (stages I and II, n = 39) and late-stage PBC (stages III and IV, n = 27). Emperipolesis was measured in liver sections stained with haematoxylin-eosin. The expressions of CK19, CD3, CD4, CD8, CD20, Ki67 and apoptosis of BECs were evaluated by immunohistochemistry or immunofluorescence double labelling. Emperipolesis was observed in 62.1% of patients with PBC, and BECs were predominantly host cells. The number of infiltrating CD3+ and CD8+ T cells correlated with the advancement of emperipolesis (R2  = 0.318, P < .001; R2  = 0.060, P < .05). The cell numbers of TUNEL-positive BECs and double staining for CK19 and Ki67 showed a significant positive correlation with emperipolesis degree (R2  = 0.236, P < .001; R2  = 0.267, P < .001). We conclude that emperipolesis mediated by CD8+ T cells appears to be relevant to apoptosis of BEC and thus may aggravate the further injury of interlobular bile ducts.

[Change of intracellular Ca2+ concentration and related signaling pathway in hippocampal cells after high-intensity sound exposure].

High-intensity sound often leads to the dysfunction and impairment of central nervous system (CNS), but the underlying mechanism is unclear. The present study was aimed to investigate the related mechanisms of CNS lesions in Bama miniature pig model treated with high-intensity sound. The pigs with normal hearing were divided into control and high-intensity sound (900 Hz-142 dB SPL, 15 min) groups. After the treatment, hippocampi were collected immediately. Fluo-4 was used to indicate intracellular Ca2+ concentration ([Ca2+]i) change. Real-time PCR and Western blot were used to detect mRNA and protein expressions of calcium-sensing receptor, L-Ca2+ channel α2/δ1 subunit, PKC and PI3K, respectively. DAPI staining was used to identify nuclear features. The result showed that high-intensity sound exposure resulted in significantly swollen cell nucleus and increased [Ca2+]i in hippocampal cells. Compared with control group, high-intensity sound group showed increased levels of PI3K, PKC and L-Ca2+ channel α2/δ1 subunit mRNA expressions, as well as up-regulated PKC and calcium-sensing receptor protein expressions. These results suggest that the high-intensity sound activates PKC signaling pathway and induces calcium overload, eventually leads to hippocampal injury, which would supply a novel strategy to prevent nervous system from high-intensity sound-induced injury.

Hepatobiliary and pancreatic: Comparison between Chinese herbal medicine and Western medicine-induced liver injury of 1985 patients.

BACKGROUND AND AIM: Chinese herbal medicine (CHM), as well as Western medicine (WM), is an important cause of drug-induced liver injury (DILI). However, the differences between CHM and WM as agents implicated in liver injury have rarely been reported. METHODS: Overall, 1985 (2.05%) DILI cases were retrospectively collected from the 96 857 patients hospitalized because of liver dysfunction in the 302 Military Hospital between January 2009 and January 2014. RESULTS: In all the enrolled patients with DILI, CHM was implicated in 563 cases (28.4%), while 870 cases (43.8%) were caused by WM and the remaining patients (27.8%) by the combination of WM and CHM. Polygonum multiflorum was the major implicated CHM. Compared with WM, the cases caused by CHM showed more female (51 vs 71%, P < 0.001) and positive rechallenge (6.1 vs 8.9%, P = 0.046), a much greater proportion of hepatocellular injury (62.2 vs 88.5%, P < 0.001), and a higher mortality (2.8 vs 4.8%, P = 0.042); however, no differences in the rates of chronic DILI and ALF were found (12.9 vs 12.4%, P = 0.807; 7.6 vs 7.6%, P = 0.971). Based on Roussel Uclaf Causality Assessment Method, 75.6% of cases caused by CHM were classified as probable and only 16.6% as highly probable, significantly different from WM (38.4 and 60.3%, all P < 0.001). CONCLUSIONS: The causal relationship between CHM and liver injury is much complex, and the clinical characteristics of DILI caused by CHM differ from those caused by WM.

Methylene Blue Reduces Acute Cerebral Ischemic Injury via the Induction of Mitophagy.

The treatment of stroke is limited by a short therapeutic window and a lack of effective clinical drugs. Methylene blue (MB) has been used in laboratories and clinics since the 1890s. Few studies have reported the neuroprotective role of MB in cerebral ischemia-reperfusion injury. However, whether and how MB protects against acute cerebral ischemia (ACI) injury was unclear. In this study, we investigated the effect of MB on this injury and revealed that MB protected against ACI injury by augmenting mitophagy. Using a rat middle cerebral artery occlusion (MCAO) model, we demonstrated that MB improved neurological function and reduced the infarct volume and necrosis after ACI injury. These improvements depended on the effect of MB on mitochondrial structure and function. ACI caused the disorder and disintegration of mitochondrial structure, while MB ameliorated the destruction of mitochondria. In addition, mitophagy was inhibited at 24 h after stroke and MB augmented mitophagy. In an oxygen-glucose deprivation (OGD) model in vitro, we further revealed that the elevation of mitochondrial membrane potential (MMP) by MB under OGD conditions mediated the augmented mitophagy. In contrast, exacerbating the decline of MMP during OGD abolished the MB-induced activation of mitophagy. Taken together, MB promotes mitophagy by maintaining the MMP at a relatively high level, which contributes to a decrease in necrosis and an improvement in neurological function, thereby protecting against ACI injury.

Nerve growth factor promotes human sperm motility in vitro by increasing the movement distance and the number of A grade spermatozoa.

Nerve growth factor (NGF) was first found in the central nervous system and is now well known for its multiple pivotal roles in the nervous system and immune system. However, more and more evidences showed that NGF and its receptors TrkA and p75 were also found in the head and tail of spermatozoa, which indicate the possible effect of NGF on the sperm motility. Nevertheless, the exact role of NGF in the human sperm motility remains unclear until now. In this study, we investigated the effect of NGF on human sperm motility, and the results showed that NGF could promote human sperm motility in vitro by increasing the movement distance and the number of A grade spermatozoa. Further analysis demonstrated that NGF promoted the sperm motility in a dose-dependent manner in vitro. These results may facilitate the further studies on human fertility and assisted reproduction techniques.

[Clinical Analysis of Drug-induced Liver Injury Caused by Polygonum multiflorum and its Preparations].

OBJECTIVE: To analyze hepatotoxicity of Polygonum multiflorum and clinical character- istics of drug-induced liver injury (DILI) caused by Polygonum multiflorum and its preparations. METHODS: A retrospective study was performed in 158 patients treated at 302 Military Hospital between January 2009 and January 2014. All of them had used Polygonum multiflorum and its preparations before the onset of DILI, and their clinical characteristics and prognoses were analyzed. RESULTS: Of the 158 DILI patients who used Polygonum multiflorum or its preparations, 92 (58.2%) combined with Western medicine or Chinese herbal preparations without Polygonum multiflorum; 66 patients (41.8%) used Polygonum mult florum and its preparations alone. In 66 DILI patients induced by Polygonum multiflorum or its preparations alone, 51 cases (77.3%) were induced by Polygonum multiflorum compounds and 22.7% by single Po- lygonum multiflorum; 4 cases (6.1%) were caused by crude Polygonum multiflorum and 62 (93.9%) by processed Polygonum multiflorum and its preparations. Clinical injury patterns were hepatocellular 92.4% (61 cases), cholestatic 1.5% (1 case), and mixed 6.1% (4 cases). Pathological examination was per- formed by liver biopsy in 32 cases (48.15%), manifested as hepatocellular degeneration and necrosis, fibroplasia, Kupffer cells with pigment granule, and a large number of eosinophil infiltration, were ob- served. Four patients were developed into liver failure, 4 into cirrhosis, and 1 died. CONCLUSION: Polygo- num multiflorum and its preparations could induce DILI, but clinical diagnosis of Polygonum multiflorum induced hepatotoxicity should be cautious.

Comprehensive pan-cancer investigation of carnosine dipeptidase 1 and its prospective prognostic significance in hepatocellular carcinoma.

Carnosine dipeptidase 1 (CNDP1), an enzyme integral to the hydrolysis of dipeptides containing histidine, plays an indispensable role in myriad physiological processes, including hydrolysis of proteins, maturation of specific biochemical functionalities within proteins, tissue regeneration, and regulation of cell cycle. However, the implications of CNDP1 in oncogenesis and its prognostic value are not yet fully elucidated. Initially, we procured the GSE40367 dataset from the Gene Expression Omnibus and established a protein-protein interaction network. Thereafter, we conducted functional and pathway enrichment analyses utilizing GO, KEGG, and GSEA. Moreover, we undertook an association analysis concerning the expression of CNDP1 with immune infiltration, along with survival analysis across various cancers and specifically in hepatocellular carcinoma (HCC). Our study uncovered a total of 2,248 differentially expressed genes, with a down-regulation of CNDP1 in HCC and other cancers. Our explorations into the relationship between CNDP1 and immune infiltration disclosed a negative correlation between CNDP1 expression and the presence of immune cells in HCC. Survival analyses revealed that diminished expression of CNDP1 correlates with an adverse prognosis in HCC and several other types of cancer. These observations intimate that CNDP1 holds promise as a novel prognostic biomarker for both pan-cancer and HCC.

Nomogram for preoperative estimation of microvascular invasion risk in hepatocellular carcinoma.

Microvascular invasion (MVI) is an adverse prognostic indicator of tumor recurrence after surgery for hepatocellular carcinoma (HCC). Therefore, developing a nomogram for estimating the presence of MVI before liver resection is necessary. We retrospectively included 260 patients with pathologically confirmed HCC at the Fifth Medical Center of Chinese PLA General Hospital between January 2021 and April 2024. The patients were randomly divided into a training cohort (n = 182) for nomogram development, and a validation cohort (n = 78) to confirm the performance of the model (7:3 ratio). Significant clinical variables associated with MVI were then incorporated into the predictive nomogram using both univariate and multivariate logistic analyses. The predictive performance of the nomogram was assessed based on its discrimination, calibration, and clinical utility. Serum carnosine dipeptidase 1 ([CNDP1] OR 2.973; 95 % CI 1.167-7.575; p = 0.022), cirrhosis (OR 8.911; 95 % CI 1.922-41.318; p = 0.005), multiple tumors (OR 4.095; 95 % CI 1.374-12.205; p = 0.011), and tumor diameter ≥3 cm (OR 4.408; 95 % CI 1.780-10.919; p = 0.001) were independent predictors of MVI. Performance of the nomogram based on serum CNDP1, cirrhosis, number of tumors and tumor diameter was achieved with a concordance index of 0.833 (95 % CI 0.771-0.894) and 0.821 (95 % CI 0.720-0.922) in the training and validation cohorts, respectively. It fitted well in the calibration curves, and the decision curve analysis further confirmed its clinical usefulness. The nomogram, incorporating significant clinical variables and imaging features, successfully predicted the personalized risk of MVI in HCC preoperatively.

Lecithin-cholesterol acyltransferase is a potential tumor suppressor and predictive marker for hepatocellular carcinoma metastasis.

BACKGROUND: Hepatocellular carcinoma (HCC) is a major cause of cancer mortality worldwide, and metastasis is the main cause of early recurrence and poor prognosis. However, the mechanism of metastasis remains poorly understood. AIM: To determine the possible mechanism affecting HCC metastasis and provide a possible theoretical basis for HCC treatment. METHODS: The candidate molecule lecithin-cholesterol acyltransferase (LCAT) was screened by gene microarray and bioinformatics analysis. The expression levels of LCAT in clinical cohort samples was detected by quantitative real-time polymerase chain reaction and western blotting. The proliferation, migration, invasion and tumor-forming ability were measured by Cell Counting Kit-8, Transwell cell migration, invasion, and clonal formation assays, respectively. Tumor formation was detected in nude mice after LCAT gene knockdown or overexpression. The immunohistochemistry for Ki67, E-cadherin, N-cadherin, matrix metalloproteinase 9 and vascular endothelial growth factor were performed in liver tissues to assess the effect of LCAT on HCC. Gene set enrichment analysis (GSEA) on various gene signatures were analyzed with GSEA version 3.0. Three machine-learning algorithms (random forest, support vector machine, and logistic regression) were applied to predict HCC metastasis in The Cancer Genome Atlas and GEO databases. RESULTS: LCAT was identified as a novel gene relating to HCC metastasis by using gene microarray in HCC tissues. LCAT was significantly downregulated in HCC tissues, which is correlated with recurrence, metastasis and poor outcome of HCC patients. Functional analysis indicated that LCAT inhibited HCC cell proliferation, migration and invasion both in vitro and in vivo. Clinicopathological data showed that LCAT was negatively associated with HCC size and metastasis (HCC size ≤ 3 cm vs 3-9 cm, P < 0.001; 3-9 cm vs > 9 cm, P < 0.01; metastatic-free HCC vs extrahepatic metastatic HCC, P < 0.05). LCAT suppressed the growth, migration and invasion of HCC cell lines via PI3K/AKT/mTOR signaling. Our results indicated that the logistic regression model based on LCAT, TNM stage and the serum level of α-fetoprotein in HCC patients could effectively predict high metastatic risk HCC patients. CONCLUSION: LCAT is downregulated at translational and protein levels in HCC and might inhibit tumor metastasis via attenuating PI3K/AKT/mTOR signaling. LCAT is a prognostic marker and potential therapeutic target for HCC.

Efficient gene transfer into neonatal mouse brain using electroporation.

In vivo electroporation works as an effective method to transfer exogenous genes into postnatal rodent forebrain. Nevertheless, two deficiencies were found in the reported methods. First, surgical operation brings unnecessary trauma to newborn pups. Second, the procedure was complicated and the transfection efficiency was relatively low. Here we improved the previous electroporation method and make it more simple and efficient. The pulse voltage was decreased to 90 v. DNA injection into one pup's forebrain could be completed within 30 s without any surgical operation. More than 94% of injected neonates survived. Almost 100% of the survivors expressed the introduced gene and the expression persists as long as 20 days after injection. Thus, this method offers a powerful new way for gene function study in postnatal neurogenesis and neural development.

[Study on the status and related socio-psychological factors of maternal depression among high-risk pregnancy women in Harbin city].

OBJECTIVE: This study aimed to investigate the depression status among high-risk pregnancy women, and to analyze its relevant social and psychological factors. METHODS: A total of 42 high-risk pregnancy women and 40 normal pregnancy women in a teaching hospital in Harbin city were followed up at time points of 32 - 36 weeks pregnancy, one week before labor, one week postpartum, and six weeks postpartum, respectively. During follow-up, the basic situation, social psychosocial factors of pregnancy women were collected and the depression of pregnancy women was measured by self-designed questionnaire and self-rating depression scale. The Edinburgh Postnatal Depression Scale (EPDS) was applied at timepoint of one week postpartum. Single factor analysis and the unconditional multivariate logistic regression were applied for analyzing the on the related social-psychosocial factors among high-risk pregnancy women. RESULTS: The age of high-risk pregnancy women was (31.0±5.6), and the age of normal pregnancy women was (30.5±3.8) (t=0.169, P>0.05). The results showed that the depression rate in high-risk pregnancy women was 45.2% (19/42), which was 25.0% (10/40) in normal pregnancy women, the difference was significant (χ2=3.671, P=0.045). The depression rates at different time points were 30.9% (13/42), 42.9% (18/42), 23.8% (10/42), 26.2% (11/42) in high-risk pregnancy women respectively, and 25.0% (10/40), 15.0% (6/40), 20.0% (8/40), 17.5% (7/40) in the control group respectively, the difference of the depression rates among groups at one week before labor was significant (χ2=7.680, P<0.01), the difference among groups at 32-36 weeks pregnancy (χ2=0.133, P=0.80), at one week postpartum (χ2=0.174, P=0.79) and at six weeks postpartum (χ2=0.903, P=0.43) were not significant. At one week postpartum and six weeks postpartum periods, the EPDS depression rate were 12.5% (4/32), 30.4% (7/23) in case group respectively, 8.3% (3/36), 22.9% (8/35) in control group respectively, the difference were not significant (χ2=0.319, 0.416, P=0.573, 0.519). There were significantly associations between the depression mood of one week before labor and the depressive symptoms of six weeks postpartum in both groups (r=0.824, 0.677, both P values were <0.05). The risk factors for maternal depression among high-risk pregnancy women were not ready for production (OR=2.73, P<0.01) and fearing of childbirth safety (OR=2.89, P<0.01). CONCLUSION: The depression date of high-risk pregnancy was high, especially at the time point one week before labor. Risk factors of maternal depression among high-risk pregnancy were "not ready for production" and "fear of childbirth safety".

Developing a New qFIBS Model Assessing Histological Features in Pediatric Patients With Non-alcoholic Steatohepatitis.

Background: The evolution of pediatric non-alcoholic fatty liver disease (NAFLD) to non-alcoholic steatohepatitis (NASH) is associated with unique histological features. Pathological evaluation of liver specimen is often hindered by observer variability and diagnostic consensus is not always attainable. We investigated whether the qFIBS technique derived from adult NASH could be applied to pediatric NASH. Materials and Methods: 102 pediatric patients (<18 years old) with liver biopsy-proven NASH were included. The liver biopsies were serially sectioned for hematoxylin-eosin and Masson trichrome staining for histological scoring, and for second harmonic generation (SHG) imaging. qFIBS-automated measure of fibrosis, inflammation, hepatocyte ballooning, and steatosis was estabilshed by using the NASH CRN scoring system as the reference standard. Results: qFIBS showed the best correlation with steatosis (r = 0.84, P < 0.001); with ability to distinguish different grades of steatosis (AUROCs 0.90 and 0.98, sensitivity 0.71 and 0.93, and specificity 0.90 and 0.90). qFIBS correlation with fibrosis (r = 0.72, P < 0.001) was good with high AUROC values [qFibrosis (AUC) > 0.85 (0.85-0.95)] and ability to distinguish different stages of fibrosis. qFIBS showed weak correlation with ballooning (r = 0.38, P = 0.028) and inflammation (r = 0.46, P = 0.005); however, it could distinguish different grades of ballooning (AUROCs 0.73, sensitivity 0.36, and specificity 0.92) and inflammation (AUROCs 0.77, sensitivity 0.83, and specificity 0.53). Conclusion: It was demonstrated that when qFIBS derived from adult NASH was performed on pediatric NASH, it could best distinguish the various histological grades of steatosis and fibrosis.

3D spongy nanofiber structure Fe-NC catalysts built by a graphene regulated electrospinning method.

3D spongy nanofiber structure Fe-NC catalysts were constructed by a graphene regulated electrospinning method. The framework of the catalysts was reconstructed into carbon nanotubes, mesopores and macropores, and most of the Fe3C is converted to Fe2N during the calcination process. All catalysts showed better electrocatalytic performances than commercial Pt/C.

Dual lentivirus infection potentiates neuroinflammation and neurodegeneration: viral copassage enhances neurovirulence.

Infection by multiple lentiviral strains is recognized as a major driving force in the human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS) epidemic, but the neuropathogenic consequences of multivirus infections remain uncertain. Herein, we investigated the neurovirulence and underlying mechanisms of dual lentivirus infections with distinct viral strains. Experimental feline immunodeficiency virus (FIV) infections were performed using cultured cells and an in vivo model of AIDS neuropathogenesis. Dual infections were comprised of two FIV strains (FIV-Ch and FIV-PPR) as copassaged or superinfected viruses, with subsequent outcome analyses of host immune responses, viral load, neuropathological features, and neurobehavioral performance. Dual infections of feline macrophages resulted in greater IL-1beta (interleukin-1beta), TNF-alpha (tumor necrosis factor alpha), and IDO (indoleamine 2,3-dioxygenase) expression and associated neurotoxic properties. FIV coinfection and sequential superinfection in vivo also induced greater IL-1beta, TNF-alpha, and IDO expression in the basal ganglia (BG) and cortex (CTX), compared to the monovirus- and mock-infected groups, although viral loads were similar in single virus- and dual virus-infected animals. Immunoblot analyses disclosed lower synaptophysin immunoreactivity in the CTX resulting from FIV super- and coinfections. Cholinergic and GABAergic neuronal injury was evident in the CTX of animals with dual FIV infections. With increased glial activation and neuronal loss in dual FIV-infected brains, immunohistochemical analysis also revealed elevated detection of cleaved caspase-3 in dysmorphic neurons, which was associated with worsened neurobehavioral abnormalities among animals infected with the copassaged viruses. Dual lentivirus infections caused an escalation in neuroinflammation and ensuing neurodegeneration, underscoring the contribution of infection by multiple viruses to neuropathogenesis.

DIXDC1 promotes retinoic acid-induced neuronal differentiation and inhibits gliogenesis in P19 cells.

Human DIXDC1 is a member of Dishevelled-Axin (DIX) domain containing gene family which plays important roles in Wnt signaling and neural development. In this report, we first confirmed that expression of Ccd1, a mouse homologous gene of DIXDC1, was up-regulated in embryonic developing nervous system. Further studies showed that Ccd1 was expressed specifically in neurons and colocalized with early neuronal marker Tuj1. During the aggregation induced by RA and neuronal differentiation of embryonic carcinoma P19 cells, expressions of Ccd1 as well as Wnt-1 and N-cadherin were dramatically increased. Stable overexpression of DIXDC1 in P19 cells promoted the neuronal differentiation. P19 cells overexpressing DIXDC1 but not the control P19 cells could differentiate into Tuj1 positive cells with RA induction for only 2 days. Meanwhile, we also found that overexpression of DIXDC1 facilitated the expression of Wnt1 and bHLHs during aggregation and differentiation, respectively, while inhibited gliogenesis by down-regulating the expression of GFAP in P19 cells. Thus, our finding suggested that DIXDC1 might play an important role during neurogenesis, overexpression of DIXDC1 in embryonic carcinoma P19 cells promoted neuronal differentiation, and inhibited gliogenesis induced by retinoic acid.

Quinacrine protects neuronal cells against heat-induced injury.

The effects of quinacrine (QA) on heat-induced neuronal injury have been explored, with the intention of understanding the mechanisms of QA protection. Primary cultivated striatum neurons from newborn rats were treated with QA 1h before heat treatment at 43 degrees C which lasted for another 1h, and necrosis and apoptosis were detected by Annexin-V-FITC and propidium iodide (PI) double staining. Neuronal apoptosis was determined using terminal deoxynucleotidyl transferase-mediated biotinylated UTP nick end labeling (TUNEL) techniques. Cell membrane fluidity, activity of cytosolic phospholipase A(2) (cPLA(2)) and the level of arachidonic acid (AA) were also examined. Membrane surface ultrastructure of striatum neurons was investigated by atomic force microscopy (AFM). Results showed that heat treatment induced great striatum neurons death, with many dying neurons undergoing necrosis rather than apoptosis. QA alone had little effect on the survival of striatum neurons, while QA pretreatment before heat treatment decreased necrosis. Heat treatment also resulted in decreased membrane fluidity and increased cPLA(2) activity as well as arachidonic acid level; these effects were reversed by QA pretreatment. QA pretreatment also significantly prevented damage to the membrane surface ultrastructure of heat-treated neurons. These results suggest that QA protects striatum neurons against heat-induced neuronal necrosis, and also demonstrate that inhibition of cPLA(2) activity and stabilization of membranes may contribute to protective effect of quinacrine.

[Prophylactic effect of quinacrine against experimental heatstroke].

The present study is to assess the prophylactic effect of quinacrine (QA) , an anti-malarial drug, against heatstroke in rats. Conscious rats were orally given equal volume normal saline or QA (dissolved in normal saline and final dosage for rats was 4.5, 9.0 and 18 mg x kg(-1)). An hour later rats were put into a warm water circulated hot chamber (41.0 +/- 0.5) degrees C. Rectal temperature (core temperature, T(co)) of rats in hot chamber was continuously monitored by a thermocouple. T(co) and survival time of rats showed that QA pre-treatment postponed the hyperthermia, and increased the survival time of rats in hot chamber. Primary striatum neurons' culture from new born rats was maintained with D-MEM and 10% FBS. After immuno-cytochemistry identification with antibodies against neural specific proteins, culture received 20 micromol x L(-1) QA only for 1 h and followed by 43.0 degrees C heat treatment for another hour, or 20 micromol x L(-1) QA for 1 h followed by 43.0 degrees C heat treatment for another hour. Control culture received heat treatment only. Cultures were labeled with the fluorescent indicator DPH and the relative membrane fluidity of neurons was measured with the help of fluorescent polarized spectrophotometer. [3H] Arachidonic acid (AA) labeled membrane of E. Coli cells was used as substrate to determine cPLA2 activity of neurons. Gas chromatography and mass spectrum were also employed to detect on the level of fatty acids level in rat striatum neurons. Results from cells indicated that inhibition of cPLA2, reduction the release of active fatty acids such as AA, and possibly, stabilization of the cell membrane which was disturbed by hot treatment, may contribute to the mechanism underlying heat protection and heatstroke preventive effects of quinacrine.

[A study of the effectiveness and cost of de-escalation therapy for severe lower airway infection in a respiratory intensive care unit].

OBJECTIVE: To evaluate the effectiveness of de-escalation therapy (DET) in patients with severe lower airway infection in the respiratory care unit. METHODS: Sixty-seven cases of severe lower airway infection (SLAI) were divided into two groups: a DET group (n = 29), and a non-DET group (NDET, n = 38). Samples of lower airway secretions were collected by blinded protected specimen brush for culture and Gram stain. The clinical data were compared between the DET group and the NDET group, including the time of mechanical ventilation, time of stay in hospital, APACHE-II score, treatment responses and outcome, cost of antibiotics and total cost in the hospital. RESULTS: There were significant differences in time in hospital (14 +/- 8; 19 +/- 12), the time of mechanical ventilation (22 +/- 16; 32 +/- 16) and the total cost in-hospital (52 871 +/- 54 457; 82 913 +/- 49 564. t = 2.195, 2.449, 2.354, all P < 0.05), while there was no significant difference in the cost on antibiotics between the DET group (7896 +/- 4718) and the NDET group (8490 +/- 5786. t = 0.449, P > 0.05). The mortality and inappropriate antibiotic therapy rate of the DET group (13.8%, 27.6%) were lower than those of the NDET group (36.8%, 60.5%; chi(2) = 4.45, 7.18, all P < 0.05). CONCLUSION: The mortality of SLAI was significantly decreased by DET. DET also led to shorter time of mechanical ventilation, shorter course of therapy and less total cost of therapy.

Screening for glutamate-induced and dexamethasone-downregulated epilepsy-related genes in rats by mRNA differential display.

BACKGROUND: It is known that excessive release of glutamate can induce excitotoxicity in neurons and lead to seizure. Dexamethasone has anti-seizure function. The aim of this study was to investigate glutamate-dexamethasone interaction in the pathogenesis of epilepsy, identify differentially expressed genes in the hippocampus of glutamate-induced epileptic rats by mRNA differential display, and observe the effects of dexamethasone on these genes expression. METHODS: Seizure models were established by injecting 5 microl (250 microg/microl) monosodium glutamate (MSG) into the lateral cerebral ventricle in rats. Dexamethasone (5 mg/kg) was injected intraperitoneally at 30 minutes after MSG inducing convulsion. The rats' behavior and electroencephalogram (EEG) were then recorded for 1 hour. The effects of dexamethasone on gene expression were observed in MSG-induced epileptic rats at 1 hour and 6 hours after the onset of seizure by mRNA differential display. The differentially expressed genes were confirmed by Dot blot. RESULTS: EEG and behaviors showed that MSG did induce seizure, and dexamethasone could clearly alleviate the symptom. mRNA differential display showed that MSG increased the expression of some genes in epileptic rats and dexamethasone could downregulate their expression. From more than 10 differentially expressed cDNA fragments, we identified a 226 bp cDNA fragment that was expressed higher in the hippocampus of epileptic rats than that in the control group. Its expression was reduced after the administration of dexamethasone. Sequence analysis and protein alignment showed that the predicted amino acid sequence of this cDNA fragment kept 43% identity to agmatinase, a member of the ureohydrolase superfamily. CONCLUSIONS: The results of the current study suggest that the product of the 226 bp cDNA has a function similar to agmatinase. Dexamethasone might relax alleviate seizure by inhibiting expression of the gene.