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71.
72.
Mayu Miyanohara Susumu Imai Masaaki Okamoto Wataru Saito Yoshiaki Nomura Yasuko Momoi Masaki Tomonaga Nobuhiro Hanada 《Microbiology and immunology》2013,57(5):359-365
The aim of this study was to analyze the distribution and phenotypic properties of the indigenous streptococci in chimpanzee (Pan troglodytes) oral cavities. Eleven chimpanzees (aged from 9 to 44 years, mean ± SD, 26.9 ± 12.6 years) in the Primate Research Institute of Kyoto University were enrolled in this research and brushing bacterial samples collected from them. Streptococci were isolated from the oral cavities of all chimpanzees. The isolates (n = 46) were identified as thirteen species by 16S rRNA genes analysis. The predominant species was Streptococcus sanguinis of mitis streptococci from five chimpanzees (45%). Mutans streptococci were isolated from six chimpanzees (55%). The predominant species in the mutans streptococci were Streptococcus troglodytae from four chimpanzees (36%), this species having been proposed as a novel species by us, and Streptococcus dentirousetti from three chimpanzees (27%). Streptococcus mutans was isolated from one chimpanzee (9%). However, Streptococcus sobrinus, Streptococcus macacae and Streptococcus downei, which are indigenous to human and monkey (Macaca fasciclaris) oral habitats, were not isolated. Of the mutans streptococci, S. troglodytae, S. dentirousetti, and S. mutans possessed strong adherence activity to glass surface. 相似文献
73.
《Journal of liposome research》2013,23(1):54-60
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
74.
《Chronobiology international》2013,30(6):1222-1234
We performed a longitudinal study to investigate whether changes in social zeitgebers and age alter sleep patterns in students during the transition from high school to university. Actimetry was performed on 24 high-school students (mean age?±?SD: 18.4?±?0.9 yrs; 12 females) for two weeks. Recordings were repeated in the same subjects 5 yrs later when they were university students. The sleep period duration and its center, the mid-sleep time, and total sleep time were estimated by actimetry. Actigraphic total sleep time was similar when in high school and at the university on school days (6.31?±?0.47 vs. 6.45?±?0.80?h, p?=?ns) and longer on leisure days by 1.10?±?1.10?h (p?<?0.0001 vs. school days) when in high school, but not at the university. Compared to the high school situation, the mid-sleep time was delayed when at the university on school days (03∶11?±?0.6 vs. 03∶55?±?0.7?h, p?<?0.0001), but not on leisure days. Individual mid-sleep times on school and leisure days when in high school were significantly correlated with the corresponding values 5 yrs later when at the university (r?=?0.58 and r?=?0.55, p?<?0.05, respectively). The large differences in total sleep time between school and leisure days when students attended high school and the delayed mid-sleep time on school days when students attended university are consistent with a circadian phase shift due to changes in class schedules, other zeitgebers, and lifestyle preferences. Age-related changes may also have occurred, although some individuality of the sleep pattern was maintained during the 5 yr study span. These findings have important implications for optimizing school and work schedules in students of different age and level of education. (Author correspondence: pneubloc@usz. uzh. ch) 相似文献
75.
Camila Mello dos Santos Aline Blaya Martins Renato José de Marchi Juliana Balbinot Hilgert Fernando Neves Hugo Dalva Maria Pereira Padilha 《Gerodontology》2013,30(3):176-186
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
76.
Conrad M. Freuling Katie Hampson Thomas Selhorst Ronald Schr?der Francois X. Meslin Thomas C. Mettenleiter Thomas Müller 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2013,368(1623)
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
77.
Ilya A. Volodin Olga V. Sibiryakova Lyudmila E. Kokshunova Roland Frey Elena V. Volodina 《Bioacoustics.》2013,22(2):79-98
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
78.
《Bioscience, biotechnology, and biochemistry》2013,77(5):1118-1126
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
79.
对珠子参茎、叶、花的氨基酸组成与含量进行测定和营养评价分析。结果表明,珠子参茎、叶、花中均含有17种常见氨基酸,氨基酸总量分别为3.73%,14.80%和8.72%;珠子参的茎中必需氨基酸与总氨基酸的比值(E/T)为0.39,必需氨基酸与非必需氨基酸的比值(E/N)为0.64,叶中E/T为0.41,E/N为0.71,花中E/T为0.39,E/N为0.63,氨基酸配比较为合理;珠子参茎、叶、花中蛋氨酸+胱氨酸均为第一限制氨基酸;珠子参茎、叶、花中均含有γ-氨基丁酸,含量分别为0.12%,0.26%和0.16%,叶片中γ-氨基丁酸的含量最高。 相似文献
80.
M. J. A. M. Clausen L. J. Melchers M. F. Mastik L. Slagter-Menkema H. J. M. Groen B. F. A. M. van der Laan 《Epigenetics》2016,11(9):653-663
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