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101.
102.
We report in this work the preparation and in vitro antimicrobial evaluation of novel amphiphilic aromatic amino alcohols synthesized by reductive amination of 4-alkyloxybenzaldehyde with 2-amino-2-hydroxymethyl-propane-1,3-diol. The antibacterial activity was determined against four standard strains (Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli, Pseudomonas aeruginosa) and 21 clinical isolates of methicillin-resistant Staphylococcus aureus. The antifungal activity was evaluated against four yeast (Candida albicans, Candida tropicalis, Candida glabrata and Candida parapsilosis). The results obtained showed a strong positive correlation between the lipophilicity and the antibiotic activity of the tested compounds. The best activities were obtained against the Gram-positive bacteria (MIC = 2–16 μg ml?1) for the five compounds bearing longer alkyl chains (4cg; 8–14 carbons), which were also the most active against Candida (MIC = 2–64 μg ml?1). Compound 4e exhibited the highest levels of inhibitory activity (MIC = 2–16 μg ml?1) against clinical isolates of MRSA. A concentration of twice the MIC resulted in bactericidal activity of 4d against 19 of the 21 clinical isolates.  相似文献   
103.
This study investigated the nitric oxide (NO) role as a mediator of arginine on bacterial translocation (BT) and gut damage in mice after intestinal obstruction (IO). The effects of pretreatment with arginine with or without NO inhibition on the systemic and local immunological response were also assessed. Mice were categorized into four groups. Group ARG received chow containing 2 % arginine, while group ARG + l-NAME received the same diet plus l-NAME (N-nitro-l-arginine methyl ester) by gavage. The IO and Sham groups were fed standard chow. After 7 days, animals were gavaged with radiolabeled Escherichia coli, anesthetized and subjected to IO, except the Sham group. Animals were euthanized after 18 h, and BT was evaluated in the mesenteric lymph nodes, blood, liver, spleen and lungs. In another experiment, the intestinal injury was assessed regarding intestinal permeability and ileum histological analyses. Intestinal secretory immunoglobulin A (sIgA) levels, serum IFN-γ and IL-10 cytokines were assessed. Arginine reduced BT, but NO inhibition enhanced BT compared with the ARG group (p < 0.05). Intestinal permeability in the ARG and ARG + l-NAME groups was similar but decreased when compared with the IO group (p < 0.05). Histological preservation was observed. Arginine treatment increased IL-10 and sIgA levels when compared with the Sham and IO groups (p < 0.05). The cytokines and sIgA concentrations were similar in the ARG + l-NAME and Sham groups. Arginine appeared to reduce BT and its effects on the modulation of cytokines and secretory IgA in mice after IO are mediated by NO production.  相似文献   
104.
Nucleus raphe pallidus (RPa) lies ventrally in the caudal brainstem, where it is coextensive rostrally with the nucleus raphe magnus (RMg) and caudally with the nucleus raphe obscurus (ROb). Retrograde neuronal tracing studies of our laboratory, carried out in rats and presented elsewhere, with fluorogold, true-blue or fast-blue, iontophoretically injected or by crystalline deposit, along the RPa extent, displayed many labeled pericaria at the preoptic area (POA), as well as lateral (LH) and dorsomedial (DMH) hypothalamus; paraventricular nucleus (PVN) and dorsal (DR) and median (MnR) raphe nuclei among others structures. In addition, RPa, which projects to the intermediolateral column, has been demonstrated to bear relation to many of the somatic-visceral functions also reported for POA. Iontophoretic injections of PHA-L, an anterograde tracer, in the POA subnuclei, presented terminal and varicose labeled fibers in RPa, as well as in the RMg, ROb, paraventricular thalamic (PVA), PVN and supraoptic nucleus (SO), LH, subparaventricular zone (sPVZ) and locus coeruleus (LC). Interestingly, POA, PVA, PVN, LH and SO have been described as retino- and suprachiasmatic-recipients. Taken together, these neuronal connections between brainstem raphe nuclei and POA, the similarity of functions to which they are related, as well as connections with other retino-suprachiasmatic-recipient structures, suggest that these caudal brainstem raphe nuclei could be part of the output system for the expression of some biological rhythms.  相似文献   
105.
Viral safety remains a challenge when processing a plasma‐derived product. A variety of pathogens might be present in the starting material, which requires a downstream process capable of broad viral reduction. In this article, we used a wide panel of viruses to assess viral removal/inactivation of our downstream process for Snake Antivenom Immunoglobulin (SAI). First, we screened and excluded equine plasma that cross‐reacted with any model virus, a procedure not published before for antivenoms. In addition, we evaluated for the first time the virucidal capacity of phenol applied to SAI products. Among the steps analyzed in the process, phenol addition was the most effective one, followed by heat, caprylic acid, and pepsin. All viruses were fully inactivated only by phenol treatment; heat, the second most effective step, did not inactivate the rotavirus and the adenovirus used. We therefore present a SAI downstream method that is cost‐effective and eliminates viruses to the extent required by WHO for a safe product. © 2013 American Institute of Chemical Engineers Biotechnol. Prog., 29:972–979, 2013  相似文献   
106.

Objective

The use of pictorial warning labels on cigarette packages is one of the provisions included in the first ever global health treaty by the World Health Organization against the tobacco epidemic. There is substantial evidence demonstrating the effectiveness of graphic health warning labels on intention to quit, thoughts about health risks and engaging in cessation behaviors. However, studies that address the implicit emotional drives evoked by such warnings are still underexplored. Here, we provide experimental data for the use of pictorial health warnings as a reliable strategy for tobacco control.

Methods

Experiment 1 pre-tested nineteen prototypes of pictorial warnings to screen for their emotional impact. Participants (n = 338) were young adults balanced in gender, smoking status and education. Experiment 2 (n = 63) tested pictorial warnings (ten) that were stamped on packs. We employed an innovative set-up to investigate the impact of the warnings on the ordinary attitude of packs’ manipulation, and quantified judgments of warnings’ emotional strength and efficacy against smoking.

Findings

Experiment 1 revealed that women judged the warning prototypes as more aversive than men, and smokers judged them more aversive than non-smokers. Participants with lower education judged the prototypes more aversive than participants with higher education. Experiment 2 showed that stamped warnings antagonized the appeal of the brands by imposing a cost to manipulate the cigarette packs, especially for smokers. Additionally, participants’ judgments revealed that the more aversive a warning, the more it is perceived as effective against smoking.

Conclusions

Health warning labels are one of the key components of the integrated approach to control the global tobacco epidemic. The evidence presented in this study adds to the understanding of how implicit responses to pictorial warnings may contribute to behavioral change.  相似文献   
107.

Background and objectives

Secondary hyperparathyroidism (SHPT) in CKD is associated with an increased risk for mortality, but definitive data showing that parathormone control decreases mortality is still lacking. This study aimed to compare the mortality of patients with severe SHPT submitted to parathyroidectomy(PTX) with those who did not have access to surgery.

Methods

This is a retrospective study in a cohort of 251 CKD patients with severe SHPT who were referred to a CKD-MBD Center for PTX from 2005 until 2012.

Results

Most of our patients had indication of PTX, but only 49% of them had access to this surgical procedure. After a mean follow-up of 23 months, 72 patients had died. Non-survivors were older; more often had diabetes, lower serum 25 vitamin D and mostly had not been submitted to surgery. The relative risk of death was lower in the PTX patients (0.428; 95% CI, 0.28 to 0.67; p<0.0001). After adjustments, mortality risk was dependent on age (1.04; 95% CI, 1.01 to 1.07; p = 0.002), 25 vitamin D (0.43; 95% CI, 0.24 to 0.81; p = 0.006) and no access to PTX (4.13; 95% CI, 2.16 to 7.88; p<0.0001). Results remained the same in a second model using the PTX date as the study start date for the PTX group.

Conclusions

Our data confirms the benefit of PTX on mortality in patients with severe SHPT. The high mortality encountered in our population is significant and urges the need to better treat these patients.  相似文献   
108.
Kalanchoe daigremontiana (Crassulaceae) is a medicinal plant native to Madagascar. The aim of this study was to investigate the flavonoid content of an aqueous leaf extract from Kdaigremontiana (Kd), and assess its antiherpetic potential. The major flavonoid, kaempferol 3‐Oβ‐d ‐xylopyranosyl‐(1 → 2)‐α‐l ‐rhamnopyranoside ( 1 ), was isolated from the AcOEt fraction (Kd‐AC). The BuOH‐soluble fraction afforded quercetin 3‐Oβ‐d ‐xylopyranosyl‐(1 → 2)‐α‐l ‐rhamnopyranoside ( 2 ) and the new kaempferol 3‐Oβ‐d ‐xylopyranosyl‐(1 → 2)‐α‐l ‐rhamnopyranoside‐7‐Oβ‐d ‐glucopyranoside ( 3 ), named daigremontrioside. The crude extract, Kd‐AC fraction, flavonoids 1 and 2 were evaluated using acyclovir‐sensitive strains of HSV‐1 and HSV‐2. Kd‐AC was highly active against HSV‐1 (EC50 = 0.97 μg/ml, SI > 206.1) and HSV‐2 (EC50 = 0.72 μg/ml, SI > 277.7). Flavonoids 1 and 2 showed anti‐HSV‐1 (EC50 = 7.4 μg/ml; SI > 27 and EC50 = 5.8 μg/ml; SI > 8.6, respectively) and anti‐HSV‐2 (EC50 = 9.0 μg/ml; SI > 22.2 and EC50 = 36.2 μg/ml; SI > 5.5, respectively) activities, suggesting the contribution of additional substances to the antiviral activity.  相似文献   
109.
110.

Background

Cynomolgus macaques (Macaca fascicularis) represent a feasible model for research on Chagas disease since natural T. cruzi infection in these primates leads to clinical outcomes similar to those observed in humans. However, it is still unknown whether these clinical similarities are accompanied by equivalent immunological characteristics in the two species. We have performed a detailed immunophenotypic analysis of circulating leukocytes together with systems biology approaches from 15 cynomolgus macaques naturally infected with T. cruzi (CH) presenting the chronic phase of Chagas disease to identify biomarkers that might be useful for clinical investigations.

Methods and Findings

Our data established that CH displayed increased expression of CD32+ and CD56+ in monocytes and enhanced frequency of NK Granzyme A+ cells as compared to non-infected controls (NI). Moreover, higher expression of CD54 and HLA-DR by T-cells, especially within the CD8+ subset, was the hallmark of CH. A high level of expression of Granzyme A and Perforin underscored the enhanced cytotoxicity-linked pattern of CD8+ T-lymphocytes from CH. Increased frequency of B-cells with up-regulated expression of Fc-γRII was also observed in CH. Complex and imbricate biomarker networks demonstrated that CH showed a shift towards cross-talk among cells of the adaptive immune system. Systems biology analysis further established monocytes and NK-cell phenotypes and the T-cell activation status, along with the Granzyme A expression by CD8+ T-cells, as the most reliable biomarkers of potential use for clinical applications.

Conclusions

Altogether, these findings demonstrated that the similarities in phenotypic features of circulating leukocytes observed in cynomolgus macaques and humans infected with T. cruzi further supports the use of these monkeys in preclinical toxicology and pharmacology studies applied to development and testing of new drugs for Chagas disease.  相似文献   
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