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61.
Anxiety and panic are the most common adverse effects of cannabis intoxication; reactions potentiated by stress. Data suggest that cannabinoid (CB1) receptor modulation of amygdalar activity contributes to these phenomena. Using Fos as a marker, we tested the hypothesis that environmental stress and CB1 cannabinoid receptor activity interact in the regulation of amygdalar activation in male mice. Both 30 min of restraint and CB1 receptor agonist treatment (Delta9-tetrahydrocannabinol (2.5 mg/kg) or CP55940 (0.3 mg/kg); by i.p. injection) produced barely detectable increases in Fos expression within the central amygdala (CeA). However, the combination of restraint and CB1 agonist administration produced robust Fos induction within the CeA, indicating a synergistic interaction between environmental stress and CB1 receptor activation. An inhibitor of endocannabinoid transport, AM404 (10 mg/kg), produced an additive interaction with restraint within the CeA. In contrast, fatty acid amide hydrolase (FAAH) inhibitor-treated mice (URB597, 1 mg/kg) and FAAH-/- mice did not exhibit any differences in amygdalar activation in response to restraint compared to control mice. In the basolateral (BLA) and medial amygdala, restraint stress produced a low level of Fos induction, which was unaffected by cannabinoid treatment. Interestingly, the CB1 receptor antagonist SR141716 dose-dependently increased Fos expression in the BLA and CeA. These data suggest the CeA is an important neural substrate subserving the interactions between cannabinoids and environmental stress, and could be relevant to understanding the context-dependent emotional and affective changes induced by marijuana intoxication and the role of endocannabinoid signaling in the modulation of amygdalar activity.  相似文献   
62.
Nipah virus (NiV) is an emerging zoonotic paramyxovirus that causes severe disease in humans and livestock. Due to its high pathogenicity in humans and the lack of available vaccines and therapeutics, NiV needs to be handled in biosafety level 4 (BSL-4) laboratories. Safe inactivation of samples containing NiV is thus necessary to allow further processing in lower containment areas. To date, there is only limited information available on NiV inactivation methods validated by BSL-4 facilities that can be used as a reference. Here, we compare some of the most common inactivation methods in order to evaluate their efficacy at inactivating NiV in infected cells, supernatants and organs. Thus, several physical and chemical inactivation methods, and combinations thereof, were assessed. Viral replication was monitored for 3 weeks and NiV presence was assessed by RT-qPCR, plaque assay and indirect immunofluorescence. A total of nineteen methods were shown to reduce NiV infectious particles in cells, supernatants and organs to undetectable levels. Therefore, we provide a list of methods for the safe and efficient inactivation of NiV.  相似文献   
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In autumn 2019, the Public Health Agency of Sweden identified a cluster of Salmonella Newport cases by whole genome sequencing (WGS). Cases’ distribution in place and time indicated a nation-wide ongoing outbreak. An investigation was initiated to identify the source and prevent further cases. We conducted a case–case study based on notified salmonellosis cases and a Salmonella trawling questionnaire, comparing 20 outbreak cases and 139 control cases. Food exposures were compared by adjusted odds ratios (aOR) with 95% confidence interval (CI) using logistic regression. Implicated foods were sampled. Outbreak cases were more likely to have consumed crayfish (aOR = 26; 95% CI: 6.3–105). One specific brand of imported frozen, pre-cooked whole crayfish in dill brine was identified as the source. Salmonella Newport was later detected in different batches from retail and in one sample from border control. Isolates from food samples clustered with the human outbreak strain by WGS. Although the retailer made a complete recall, two more cases were identified long afterwards. This investigation demonstrated the successful use of a case–case study and targeted microbiological testing to identify the source. The immediate action taken by the retailer was important to confirm the source and stop the outbreak.  相似文献   
64.
Carthamus tinctorius L. (Compositae) is used in Chinese medicine to treat heart disease and inflammation. In our previous study, we found that C. tinctorius L. inhibited lipopolysaccharides (LPS)‐induced tumor necrosis factor‐alpha (TNF‐α) activation, JNK expression, and apoptosis in H9c2 cardiomyoblast cells. The present study was performed to investigate the protective effect of C. tinctorius extract (CTF) on LPS‐challenged H9c2 myocardioblast cell and to explore the possible underlying mechanism. Cell viability assay showed that LPS treatment decreased the cell viability of H9c2 cell, whereas CTF treatment reversed LPS cytotoxicity in a dose‐dependent manner, especially in the LPS + CTF 25 (μg/mL) group. LPS treatment‐induced apoptosis was determined by transferase‐mediated dUTP nick end labeling assay, and by Western blot. LPS‐induced apoptotic bodies were decreased following CTF treatment. Expression of TNF‐α, FAS‐L, FAS, FADD, caspase‐8, BID, and t‐BID was significantly increased in LPS‐treated H9c2 cells. In contrast, it was significantly suppressed by the administration of CTF extract. In addition, CTF treatment activates antiapoptotic proteins, Bcl‐2 and p‐Bad, and downregulates Bax, cytochrome‐c, caspase‐9, caspase‐3, and apoptosis‐inducing factor expression. Furthermore, CTF exerted cytoprotective effects by activating insulin‐like growth factor‐I (IGF‐I) signaling pathway leading to downregulation of the apoptotic proteins involved in FAS death receptor pathway. In addition, AG1024 and IGF‐I receptor (IGF‐IR) inhibitor and siRNA silencing reverses the effect of CTF implying that CTF functions through the IGF‐IR pathway to inhibit LPS‐induced H9c2 apoptosis. These results suggest that treatment with CTF extract prevented the LPS‐induced apoptotic response through IGF‐I pathway.  相似文献   
65.
Grape pomace and berries represent natural sources of phytochemicals that can increase the quality of life of consumers by contributing to the prevention of chronic diseases; thus, the development of a dietary supplement was necessary. The raw material (r.m.) used for the development of the dietary supplement consisted of dried and powdered bilberries (Vaccinium myrtillus L.), red currants (Ribes rubrum L.), and red fermented pomaces (Vitis vinifera L.) from Feteasca Neagra and Cabernet Sauvignon cultivars. The particle size distribution, powder flow, total phenolic content (TPC), HPLC-DAD phenolic profile assessment, and radical scavenging assay (RSA) were employed for the analysis of the raw material. After encapsulation, the average mass and uniformity of mass, the disintegration, and the uniformity of content for the obtained capsules were performed to obtain a high-quality dietary supplement. All the assays performed complied to the compendial requirements and the TPC was determined at 9.07 ± 0.25 mg gallic acid equivalents/g r.m. and RSA at 48.32 ± 0.74%. The highest quantities of phenolic compounds determined were 333.7 ± 0.50 µg/g r.m. for chlorogenic acid, followed by rutin, ferulic acid, and (+)-catechin with 198.9 ± 1.60 µg/g r.m., 179.8 ± 0.90 µg/g r.m. and 118.7 ± 0.75 µg/g r.m., respectively. The results of this study can be used for the manufacturing and assessing of pilot scale-up capsule batches and thinking of quality assurance, we recommend that the industrial batch extracts should be standardized in polyphenols, and the manufacturing process should be validated.  相似文献   
66.
The prevalence of obesity at all ages is increasing epidemically worldwide. Information on the association between premenopausal breast cancer and body size during childhood and teenage years is scarce. In 1991 to 1992, a prospective cohort study was assembled in Norway and Sweden. We included in the analysis presented here 99,717 premenopausal women. During the follow-up period, which ended in December 1999, 733 of these women developed a primary invasive breast cancer. Overweight and obesity [body mass index (BMI) > 25 kg/m(2)] at enrollment was associated with a decreased risk of premenopausal breast cancer (P for linear trend = 0.007). Apparent associations between perceived body shape at age 7 and BMI at age 18, with heavier builds at both ages seemingly being protective for premenopausal breast cancer risk, lost their statistical significance after adjustment for BMI at cohort enrollment. Body size at age 7 was correlated with BMI at age 18 (r = 0.43); BMI at age 18 was correlated with adult BMI (r = 0.48). Changes in body size from age 7 or 18 to adulthood did not affect per se risk of premenopausal breast cancer risk. Height was related to risk, with a statistically significantly 30% reduced risk only in women shorter than 160 cm as compared with taller ones. The decreased risk of premenopausal breast cancer was observed in overweight and obese women without, but not in those with, a family history of breast cancer.  相似文献   
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Abstract Objective: The receptor for advanced glycation end products (RAGE) has been proposed to participate in the innate and adaptive immune responses. RAGE can induce production of pro-inflammatory cytokines and chemokines, as well as neutrophil chemotaxis in a manner that may be suppressed or stimulated by soluble, truncated forms of RAGE including the soluble form of RAGE (sRAGE) and endogenous secretory RAGE (esRAGE). The objective of this study was to determine whether intra-amniotic infection/inflammation (IAI) is associated with changes in the amniotic fluid concentration of sRAGE and esRAGE. Study design: Amniotic fluid (AF) was retrieved from patients in the following groups: 1) mid-trimester (14-18 weeks of gestation; n=68); 2) term not in labor (n=24); 3) term in labor (n=51); 4) preterm labor and intact membranes (n=124); and 5) preterm PROM (n=80). Intra-amniotic infection and inflammation were defined as the presence of a positive amniotic fluid culture for microorganisms and an AF interleukin-6 concentration >/=2.6 ng/mL, respectively. The AF concentration of sRAGE and esRAGE were determined using specific and sensitive ELISAs which measured total immunoreactive sRAGE and esRAGE, respectively. Patients were matched for gestational age at amniocentesis to compare the AF concentration of sRAGE and esRAGE in patients with and without IAI. Non-parametric statistics were used for analysis and a P<0.05 was considered significant. Results: 1) Patients at term not in labor had higher median AF concentrations of sRAGE and esRAGE than those in the mid-trimester (P<0.001 for both comparisons) and those at term in labor (P=0.03 and P=0.04, respectively); 2) patients with preterm labor and intact membranes with intra-amniotic infection/inflammation (IAI) had higher median AF concentrations of sRAGE and esRAGE than those without IAI (P=0.02 and P=0.005, respectively); 3) similarly, patients with preterm PROM with IAI had higher median AF concentrations of sRAGE and esRAGE than those without IAI (P=0.03 and P=0.02, respectively). Conclusion: Intra-amniotic infection/inflammation is associated with increased amniotic fluid concentrations of sRAGE and esRAGE. Changes in the amniotic fluid concentration of sRAGE and esRAGE may represent part of the immune response to intra-amniotic infection/inflammation.  相似文献   
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