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991.
The in vitro effects of myotoxin III (MT-III), an Asp-49 catalytically-active phospholipase A(2), and myotoxin II (MT-II), a catalytically-inactive Lys-49 variant, isolated from Bothrops asper snake venom, on phagocytosis and production of hydrogen peroxide (H(2)O(2)) by thioglycollate-elicited macrophages were investigated. MT-II and MT-III were cytotoxic to mouse peritoneal macrophages at concentrations higher than 25 microg/ml. At non-cytotoxic concentrations, MT-II stimulated Fcgamma, complement, mannose and beta-glucan receptors-mediated phagocytosis, whereas MT-III stimulated only the mannose and beta-glucan receptors-mediated phagocytosis. Moreover, both myotoxins induced the release of H(2)O(2) by thioglycollate-elicited macrophages, MT-III being the most potent stimulator. MT-II induced the release of H(2)O(2) only at a concentration of 3.2 microg/ml (130% increment) while MT-III induced this effect at all concentrations tested (0.5-2.5 microg/ml; average of 206% increment). It is concluded that, at non-cytotoxic concentrations, MT-II and MT-III activate defense mechanisms in macrophages up regulating phagocytosis, mainly via mannose and beta-glucan receptors, and the respiratory burst.  相似文献   
992.
We have previously reported on the "return trip" metastases from the liver to the pancreas in a hamster experimental pancreatic cancer model. Because the pancreas is the main metastatic site of liver-implanted pancreatic tumors, our aim was to clarify whether the metastatic sites differ in young and old tumor-bearing animals. HaP-T1, a continuous tissue-cultured cell line, derived from BHP-induced pancreatic adenocarcinoma, was implanted into the liver. The animals were divided into two groups: A) younger than 26 weeks and B) older than 26 weeks. Three animals from each group were sacrificed on Days 35, 42, 49, 56, 63, 70, 77, 84, 91 and 98, to study the metastatic sites. Survival was also studied. After death, necropsy was performed. Resected and necropsied specimens were analyzed histopathologically and by PCR/RFLP analysis to confirm the presence of K-ras point mutation. The success rate of implantation was 100%. Survival was 102.3+/-2.5 days in group A and 95.3+/-1.5 days in group B. Animals of group A, sacrificed weekly until Day 70, showed metastases only to the pancreas ("return trip"), while this phenomenon happened only in animals sacrificed on Day 35 in group B. In group A, on Days 77, 84, 91 and 98, metastases were also found in the kidneys, lymph nodes, ovary and testis. In hamsters of group B, metastases were found in multiple sites such as the pancreas, vas deferens, ovary and testis ("multiple journeys"). All intra-hepatically-implanted tumor and metastatic sites showed the K-ras point mutation. This homologous implantation model may be helpful for further research into the process of metastasis and its relationship with the immunological response.  相似文献   
993.
994.
BackgroundObesity has reached epidemic proportions worldwide, affecting life quality and span. Susceptibility to obesity is partly mediated by genetic differences. Indeed, several genes from the clock gene family have already been shown to be intimately associated with obesity in diverse ethnic groups. In the present study, an association between BMI and the rs707467, rs228697 and rs228729 PER3 (Period Circadian Clock 3) polymorphisms in subjects with class II (BMI ≥ 35.0–39.9 kg/m2) and class III obesity (>40 kg/m2, extreme obesity) were carried out using TaqMan real-time PCR. Overall, 259 Brazilian adults were genotyped, of whom 122 had class II or III obesity (BMI ≥ 35.0 kg/m2) and 137 were controls having normal weight (BMI > 18.5 and <24.9 kg/m2).ResultsPER3 tag SNP (rs228729) shows a significant association with extreme obesity (1000 permutation p = 0.03 and p = 0.04), for genotype and allele frequency respectively) and a haplotype among the three assessed SNPs (alleles G/T/A, rs228697, rs228729, and rs707467, respectively, 1000 permutation p = 0.03) was significantly more prevalent in the group with obesity.ConclusionThis exploratory association study suggests that PER3 rs228729 may be associated with extreme obesity in Brazilian adults, however, replication is needed.  相似文献   
995.
996.

Rationale

Contextual fear is evoked by re-exposing an animal to an environment that has been previously paired with an aversive or unpleasant stimulus. It can be assessed by freezing and cardiovascular changes such as increase in mean arterial pressure and heart rate. A marked increase in neuronal activity is associated with contextual fear conditioning, especially in limbic structures involved with defense reactions, such as the ventral portion of medial prefrontal cortex.

Objective

Given the fact that transient receptor potential vanilloid type 1 (TRPV1) receptors could be involved in the expression of defensive behavior, the present work tested the hypothesis that TRPV1 manipulation in the ventromedial prefrontal cortex (vMPFC) modulates the expression of contextual conditioned fear.

Methods

Male Wistar rats received bilateral microinjections into the vMPFC of the TRPV1 receptor antagonists capsazepine (1, 10, and 60 nmol/200 nL) or 6-iodonordihydrocapsaicin (3 nmol/200 nL), and the TRPV1 agonist capsaicin (1 nmol/200 nL) preceded by vehicle or 6-iodonordihydrocapsaicin before re-exposure to the experimental chamber for 10 min, 48 h after conditioning in two different protocols distinct by their aversiveness.

Results

Both antagonists reduced the freezing and cardiovascular responses in the high aversive protocol. Capsaicin caused an increase in fear-associated responses that could be blocked by 6-iodonordihydrocapsaicin.

Conclusions

Our results indicate that TRPV1 receptors located in the vMPFC have a tonic involvement in the modulation of the expression of contextual fear conditioning.  相似文献   
997.
Vulvovaginal candidiasis is an inflammation localized in the vulvovaginal area. It is mostly caused by Candida albicans. Its treatment is based on the systemic and local administration of antifungal drugs. However, this conventional therapy can fail owing to the resistance of the Candida species and noncompliance of patients. Amphotericin B-loaded poly(lactic-co-glycolic acid) nanofibers are single-use, antifungal, controlled drug delivery systems, and represent an alternative therapeutic scheme for the local treatment of vulvovaginal candidiasis. Nanofibers were characterized by analytical techniques and with an in vitro drug delivery study. In vitro and in vivo fungicidal activity of amphotericin B released from nanofibers was evaluated using the agar diffusion method and an experimental murine model of vulvovaginal candidiasis, respectively. Analytical techniques showed that amphotericin B was physically mixed in the polymeric nanofibers. Nanofibers controlled the delivery of therapeutic doses of amphotericin B for 8 consecutive days, providing effective in vitro antifungal activity and eliminated the in vivo vaginal fungal burden after 3 days of treatment and with only one local application. Amphotericin B-loaded poly(lactic-co-glycolic acid) nanofibers could be potentially applied as an alternative strategy for the local treatment of vulvovaginal candidiasis without inducing fungal resistance, yet ensuring patient compliance.  相似文献   
998.

Background

The study evaluated the effects of two sphingosine derivatives N-(2-tert-butoxycarbamylhexadecyl)glutaramide (AA) and N-(1-benzyloxyhexadec-2-yl)glutaramide (OA) in different models of hypersensitivity in mice.

Methods

Male Swiss mice were orally pre-treated with AA or OA (0.3–3 mg/kg). After 1 h, they received λ-carrageenan (300 μg/paw), lipopolysaccharide (LPS; 100 ng/paw), bradykinin (BK; 500 ng/paw) or prostaglandin E2 (PGE2; 0.1 nmol/paw) or epinephrine (100 ng/paw), and the mechanical withdrawal thresholds were evaluated using von Frey filament (0.6 g) at different time points. The effect of the compounds against inflammatory and neuropathic pain was also evaluated using complete Freund’s adjuvant (CFA), or by performing partial sciatic nerve ligation (PSNL).

Results

Animals pre-treated with AA and OA reduced hypersensitivity induced by carrageenan, LPS and BK, and modest inhibition of PGE2-induced hypersensitivity and carrageenan-induced paw oedema were observed in mice treated with OA. Though the partial effect presented by AA and OA, when dosed once a day, both compounds were able to significantly reduce the persistent inflammatory and neuropathic pain induced by CFA and PSNL, respectively.

Conclusion

These results demonstrate that the sphingosine derivatives AA and OA present important anti-hypersensitive effects, suggesting a possible interaction with the kinin signalling pathway. This may represent an interesting tool for the management of acute and chronic pain, with good bioavailability and safety.  相似文献   
999.
The development of hydrogel films as wound healing dressings is of a great interest owing to their biological tissue-like nature. Polyvinyl alcohol/polyethylene glycol (PVA/PEG) hydrogels loaded with asiaticoside, a standardized rich fraction of Centella asiatica, were successfully developed using the freeze–thaw method. Response surface methodology with Box–Behnken experimental design was employed to optimize the hydrogels. The hydrogels were characterized and optimized by gel fraction, swelling behavior, water vapor transmission rate and mechanical strength. The formulation with 8% PVA, 5% PEG 400 and five consecutive freeze–thaw cycles was selected as the optimized formulation and was further characterized by its drug release, rheological study, morphology, cytotoxicity and microbial studies. The optimized formulation showed more than 90% drug release at 12?hours. The rheological properties exhibited that the formulation has viscoelastic behavior and remains stable upon storage. Cell culture studies confirmed the biocompatible nature of the optimized hydrogel formulation. In the microbial limit tests, the optimized hydrogel showed no microbial growth. The developed optimized PVA/PEG hydrogel using freeze–thaw method was swellable, elastic, safe, and it can be considered as a promising new wound dressing formulation.  相似文献   
1000.
Introduction: Bruxism is among the most chronic dental problems worldwide, and its perception may increase indicatively the condition of people’s health, avoiding future health problems. Technologic solutions have improved considerably owing to new diagnostic and treatment technologies and their automation. This review aims to assess therapeutic methods for bruxism through analysis of patent applications spanning recent decades.

Areas covered: Patent families of bruxism, and products available on the market. Data were obtained through Questel Orbit from the European Patent Office on a worldwide basis using Cooperative Patent Classification (CPC), analyzing 134 patent families. The products on the market were mapped and classified as used for diagnosis, treatment, or both.

Expert opinion: This technological prospect has shown that the technological field of bruxism is growing toward smaller, automated devices; there is still no predominant owner of the technologies. Products are expected to provide home use with a high degree of reliability and specificity, using the Internet of Things (telemedicine associated with industry 4.0) and enabling real-time diagnosis.  相似文献   

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