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61.
The aim of the present study was to characterize a liposome-based benzocaine (BZC) formulation designed for topical use on the oral mucosa and to evaluate its in vitro retention and permeation using the Franz-type diffusion cells through pig esophagus mucosa. To predict the effectiveness of new designed formulations during preclinical studies, a correlation between in vitro assays and in vivo efficacy was performed. Liposomal BZC was characterized in terms of membrane/water partition coefficient, encapsulation efficiency, size, polydispersity, zeta potential, and morphology. Liposomal BZC (BL10) was incorporated into gel formulation and its performances were compared to plain BZC gel (B10) and the commercially available BZC gel (B20). BL10 and B10 presented higher flux and retention on pig esophagus mucosa with a shorter lag time, when compared to B20. BZC flux was strongly correlated with in vivo anesthetic efficacy, but not with topical anesthesia duration. The retention studies did not correlate with any of the in vivo efficacy parameters. Thus, in vitro permeation study can be useful to predict anesthetic efficacy during preclinical tests, because a correlation between flux and anesthetic efficacy was observed. Therefore, in vitro assays, followed by in vivo efficacy, are necessary to confirm anesthetic performance.  相似文献   
62.
doi: 10.1111/j.1741‐2358.2012.00656.x Assessing changes in oral health‐related quality of life and its factors in community‐dwelling older Brazilians Objective: To describe changes in oral health‐related quality of life and to evaluate the associations of these changes in community‐dwelling older people. Materials and methods: In this longitudinal study a representative sample of 872 older people, living in Brazil, was evaluated during 2004. The follow‐up was carried out during 2008, with 587 older persons evaluated. A questionnaire assessing socio‐demographic information, health history, oral health‐impact profile and number of natural teeth was used. Changes in oral health‐related quality of life were categorized as improvement or deterioration. Data analysis was performed using a hierarchical approach based in a conceptual framework. A hierarchal approach was carried out using Poisson regressions. Results: Older persons living in rural areas, those who reported brushing once a day or less and older persons with fewer natural teeth had an increased chance of reporting deterioration in oral health‐related quality of life. Women and participants who received a minimum wage of less than US$219.50 were more likely to report improvement in oral health‐related quality of life. Conclusion: The results of this study suggest that changes in the oral health‐related quality of life are influenced by many of the variables that were included in the conceptual framework.  相似文献   
63.
Despite perceived challenges to controlling an infectious disease in wildlife, oral rabies vaccination (ORV) of foxes has proved a remarkably successful tool and a prime example of a sophisticated strategy to eliminate disease from wildlife reservoirs. During the past three decades, the implementation of ORV programmes in 24 countries has led to the elimination of fox-mediated rabies from vast areas of Western and Central Europe. In this study, we evaluated the efficiency of 22 European ORV programmes between 1978 and 2010. During this period an area of almost 1.9 million km² was targeted at least once with vaccine baits, with control taking between 5 and 26 years depending upon the country. We examined factors influencing effort required both to control and eliminate fox rabies as well as cost-related issues of these programmes. The proportion of land area ever affected by rabies and an index capturing the size and overlap of successive ORV campaigns were identified as factors having statistically significant effects on the number of campaigns required to both control and eliminate rabies. Repeat comprehensive campaigns that are wholly overlapping much more rapidly eliminate infection and are less costly in the long term. Disproportionally greater effort is required in the final phase of an ORV programme, with a median of 11 additional campaigns required to eliminate disease once incidence has been reduced by 90 per cent. If successive ORV campaigns span the entire affected area, rabies will be eliminated more rapidly than if campaigns are implemented in a less comprehensive manner, therefore reducing ORV expenditure in the longer term. These findings should help improve the planning and implementation of ORV programmes, and facilitate future decision-making by veterinary authorities and policy-makers.  相似文献   
64.
The trunk-like nose of the saiga antelope Saiga tatarica is a striking example of an exaggerated trait, assumed to having evolved as a dust filter for inhaled air. In addition, it functions to elongate the vocal tract in harem saiga males for producing low-formant calls that serve as a cue to body size for conspecifics. This study applies the source–filter theory to the acoustics of nasal, oral and nasal-and-oral calls that were recorded from a captive herd of 24 mother and 32 neonate saigas within the first 10 days postpartum. Anatomical measurements of the nasal and oral vocal tracts of two specimens (one per age class) helped to establish the settings for the analysis of formants. In both mother and young, the lower formants of nasal calls/call parts were in agreement with the source–filter theory, which suggests lower formants for the longer nasal vocal tract than for the shorter oral vocal tract. Similar fundamental frequencies of the nasal and oral parts of nasal-and-oral calls were also in agreement with the source–filter theory, which postulates the independence of source and filter. However, the fundamental frequency was higher in oral than in nasal calls, probably due to the higher emotional arousal during the production of oral calls. We discuss production mechanisms and the ontogeny of formant patterns of oral and nasal calls among bovid and cervid species with and without a trunk-like nose.  相似文献   
65.
Sesame peptide powder (SPP) exhibited angiotensin I-converting enzyme (ACE) inhibitory activity, and significantly and temporarily decreased the systolic blood pressure (SBP) in spontaneously hypertensive rats (SHRs) by a single administration (1 and 10 mg/kg). Six peptide ACE inhibitors were isolated and identified from SPP. The representative peptides, Leu-Val-Tyr, Leu-Gln-Pro and Leu-Lys-Tyr, could competitively inhibit ACE activity at respective Ki values of 0.92 μM, 0.50 μM, and 0.48 μM. A reconstituted sesame peptide mixture of Leu-Ser-Ala, Leu-Gln-Pro, Leu-Lys-Tyr, Ile-Val-Tyr, Val-Ile-Tyr, Leu-Val-Tyr, and Met-Leu-Pro-Ala-Tyr according to their content ratio in SPP showed a strong antihypertensive effect on SHR at doses of 3.63 and 36.3 μg/kg, which accounted for more than 70% of the corresponding dosage for the SPP-induced hypotensive effect. Repeated oral administration of SPP also lowered both SBP and the aortic ACE activity in SHR. These results demonstrate that SPP would be a beneficial ingredient for preventing and providing therapy against hypertension and its related diseases.  相似文献   
66.
Oral and oropharyngeal squamous cell carcinoma (OOSCC) have a low survival rate, mainly due to metastasis to the regional lymph nodes. For optimal treatment of these metastases, a neck dissection is required; however, inaccurate detection methods results in under- and over-treatment. New DNA prognostic methylation biomarkers might improve lymph node metastases detection. To identify epigenetically regulated genes associated with lymph node metastases, genome-wide methylation analysis was performed on 6 OOSCC with (pN+) and 6 OOSCC without (pN0) lymph node metastases and combined with a gene expression signature predictive for pN+ status in OOSCC. Selected genes were validated using an independent OOSCC cohort by immunohistochemistry and pyrosequencing, and on data retrieved from The Cancer Genome Atlas. A two-step statistical selection of differentially methylated sequences revealed 14 genes with increased methylation status and mRNA downregulation in pN+ OOSCC. RAB25, a known tumor suppressor gene, was the highest-ranking gene in the discovery set. In the validation sets, both RAB25 mRNA (P = 0.015) and protein levels (P = 0.012) were lower in pN+ OOSCC. RAB25 mRNA levels were negatively correlated with RAB25 methylation levels (P < 0.001) but RAB25 protein expression was not. Our data revealed that promoter methylation is a mechanism resulting in downregulation of RAB25 expression in pN+ OOSCC and decreased expression is associated with lymph node metastasis. Detection of RAB25 methylation might contribute to lymph node metastasis diagnosis and serve as a potential new therapeutic target in OOSCC.  相似文献   
67.
目的:研究口腔雾化药物吸入联合小儿双金清热口服液治疗疱疹性口炎的临床疗效。方法:选择2012年5月至2014年5月在我院接受治疗的疱疹性口炎患者122例实施研究。根据数字法随机分成观察组及对照组各61例,观察组给予口腔雾化药物吸入以及小儿双金清热口服液进行治疗,对照组单纯给予小儿双金清热口服液进行治疗,对比两组治疗后的疗效、相关康复指标以及治疗后的不良反应。结果:观察组的总有效率是98.36%,显著高于对照组的88.52%,差异有统计学意义(P0.05)。观察组的热退时间和疱疹消退时间以及康复时间均分别显著少于对照组,差异均有统计学意义(均P0.05)。观察组治疗后的总不良反应发生率与对照组相比,差异无统计学意义(P0.05)。结论:利用口腔雾化药物吸入联合小儿双金清热口服液对疱疹性口炎患儿进行治疗,效果较好,安全性更高,值得在临床上推广应用。  相似文献   
68.
目的:探讨灯盏细辛口服液对急性冠状动脉综合征患者外周血C-反应蛋白、1-甲基环丙烯和9-基质金属蛋白酶水平的影响。方法:选取我院心内科已确诊为急性冠状动脉综合征的患者110例,随机分为实验组和对照组,对照组行常规药物治疗,实验组在对照组的基础上口服灯盏细辛口服液。比较两组患者治疗前后外周血C-反应蛋白变化情况及MCP-1及MMP-9水平及临床疗效。结果:与治疗前相比,两组患者治疗后MCP-1、MMP-9及C-反应蛋白水平降低(P0.05),与对照组相比,实验组患者MCP-1、MMP-9及C-反应蛋白较低(P0.05);与对照组相比,实验组总有效率较高(P0.05)。结论:灯盏细辛口服液对急性冠状动脉综合征患者具有较好的疗效,这可能与其降低外周血中C-反应蛋白、MMP-9和MCP-1水平具有一定的关系。  相似文献   
69.
The WHO recommends complete withdrawal of oral polio vaccine (OPV) type 2 by April 2016 globally and replacing with at least one dose of inactivated poliovirus vaccine (IPV). However, high‐cost, limited supply of IPV, persistent circulating vaccine‐derived polioviruses transmission and need for subsequent boosters remain unresolved. To meet this critical need, a novel strategy of a low‐cost cold chain‐free plant‐made viral protein 1 (VP1) subunit oral booster vaccine after single IPV dose is reported. Codon optimization of the VP1 gene enhanced expression by 50‐fold in chloroplasts. Oral boosting of VP1 expressed in plant cells with plant‐derived adjuvants after single priming with IPV significantly increased VP1‐IgG1 and VP1‐IgA titres when compared to lower IgG1 or negligible IgA titres with IPV injections. IgA plays a pivotal role in polio eradication because of its transmission through contaminated water or sewer systems. Neutralizing antibody titres (~3.17–10.17 log2 titre) and seropositivity (70–90%) against all three poliovirus Sabin serotypes were observed with two doses of IPV and plant‐cell oral boosters but single dose of IPV resulted in poor neutralization. Lyophilized plant cells expressing VP1 stored at ambient temperature maintained efficacy and preserved antigen folding/assembly indefinitely, thereby eliminating cold chain currently required for all vaccines. Replacement of OPV with this booster vaccine and the next steps in clinical translation of FDA‐approved antigens and adjuvants are discussed.  相似文献   
70.
Iryna Oliynyk 《Luminescence》2016,31(6):1213-1219
Investigation into the limits of application of chemiluminescence (CL) methods in oncology still attracts the attention of researchers. In the present work we analyze the screening and monitoring of oncological processes (OP) in the mucous membrane of the mouth and larynx by initiated CL (ICL). Chemiluminescence has already been used by stomatologists to define the start of OP, but methods that reflect the metabolic changes in organism under cancer diagnostics still have not found their place. This work presents results of ICL on blood serum (BS) of patients with oncological diseases at different stages of medical treatment compared with those of healthy people. We found an essential metabolic difference only in types of OP that are characterized by two maxima on chemiluminograms. These OP represent only 12.81% of groups of patients with oncological diseases. The possibility to apply ICL methods to monitor operation quality and control medical treatment at different stages when the two ICL maxima are present is established. At present, the chemiluminograms with the two maxima are mostly informative, but this does not exclude the quantitative analysis of other ICL kinetic methods and is encouraging for their investigation. Any OP introduces changes in organism function and these should be reflected in the ICL. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
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