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51.
Nijhof AM Bodaan C Postigo M Nieuwenhuijs H Opsteegh M Franssen L Jebbink F Jongejan F 《Vector borne and zoonotic diseases (Larchmont, N.Y.)》2007,7(4):585-595
Following an outbreak of autochthonous canine babesiosis in the Netherlands, a request made to veterinarians and the public to collect ticks from companion animals resulted in 4298 ticks submitted between July 2005 and October 2006 to our center. Ticks were identified as Ixodes ricinus adults (2907/4298, 67.6%), Ixodes sp. nymphs (529/4298, 12.3%) and Ixodes sp. larvae (385/4298, 9.0%), I. hexagonus adults (328/4298, 7.6%), Dermacentor reticulatus (72/4298, 1.7%), and several other exotic tick species such as Amblyomma flavomaculatum (formerly Aponomma flavomaculatum), Hyalomma marginatum rufipes, Rhipicephalus sanguineus, and R. turanicus (55/4298, 1.3%). Eight localities were surveyed for the presence of local D. reticulatus, a tick not indigenous to the Netherlands, based on multiple submissions of D. reticulatus ticks from these areas. D. reticulatus was collected from the vegetation in six of these localities, confirming the presence of populations of this tick in the Netherlands. Adult I. ricinus (n=251), I. hexagonus (n=237), and D. reticulatus (n=344) ticks were selected at random and subsequently screened by polymerase chain reaction (PCR) and reverse line blot (RLB) hybridization for the presence of Borrelia, Babesia, Theileria, Anaplasma, Ehrlichia, and Rickettsia species. I. ricinus ticks were infected with Rickettsia helvetica (24.7%), spirochetes belonging to the Borrelia burgdorferi sensu lato group (7.2%), the Ehrlichia-like "Schotii" variant (2.4%), Anaplasma phagocytophilum (1.6%), Babesia sp. (EU1) (1.2%), Babesia divergens (0.4%), and Babesia microti (0.4%). A. phagocytophilum (5.9%) and R. helvetica (0.8%) were also detected in adult I. hexagonus ticks. Spotted fever group Rickettsiae, previously reported as Rickettsia sp. DnS14/RpA4 (14.0%), and Borrelia burgdorferi sensu lato (0.3%) were detected in the D. reticulatus ticks, which appeared to be free from B. canis infection. We concluded that a much broader spectrum of ticks and tick-borne pathogens is present in the Netherlands than previously thought, including several potential zoonotic pathogens. 相似文献
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Philip A Merriam Trinidad L Tellez Milagros C Rosal Barbara C Olendzki Yunsheng Ma Sherry L Pagoto Ira S Ockene 《BMC medical research methodology》2009,9(1):20-9
Background
Latinos comprise the largest racial/ethnic group in the United States and have 2–3 times the prevalence of type 2 diabetes mellitus as Caucasians. 相似文献55.
Friedman SR Sandoval M Mateu-Gelabert P Meylakhs P Des Jarlais DC 《Substance use & misuse》2011,46(2-3):307-315
A positive-deviance control-case life history study of injection drug users (IDUs) in New York City who had injected drugs for 8-15 years compared 21 IDUs who were antibody negative for both HIV and hepatitis C with 3 infected with both viruses and 11 infected with hepatitis C virus but not HIV. Eligible subjects were referred from other research studies and from community organizations that conduct testing for HIV and hepatitis C virus. Data were collected during 2005-2008 and were analyzed using life history and grounded theory approaches. They support grounded hypotheses that IDUs who are able to attain symbiotic goals like avoiding withdrawal and maintaining social support are assisted thereby in remaining uninfected with HIV or hepatitis C. These hypotheses should be tested using cohort studies and prevention trials to see if helping IDUs attain symbiotic goals reduces infection risk. The study's limitations are noted. 相似文献
56.
Victor VM Rocha M Herance R Hernandez-Mijares A 《Current pharmaceutical design》2011,17(36):3947-3958
Diabetes is a chronic disease and as a consequence of the overproduction of reactive oxygen species (ROS), is related with oxidative stress. There are different sources of ROS, of which mitochondria is the main one. Oxidative stress seems to play an important role in mitochondria- mediated disease processes, though the exact molecular mechanisms responsible remain elusive. There are evidences which supports the idea that impaired mitochondrial function is a cause of the insulin insensitivity in different type of cells that arised as a result of an insufficient supply of energy or defects in the insulin signaling pathway. ROS are generally necessary for the proper functioning of the cell, but excessive ROS production can be harmful, which makes antioxidant defenses essential. Moreover, some substances with antioxidant properties, such as vitamin C or vitamin E, erradicate the oxidative stress associated with diabetes. The results of clinical trials employing anti-oxidative stress reagents in patients with diabetes are contradictory, which may be a result of inadequate study design or selected targets. This review considers the process of diabetes from a mitochondrial perspective, and describes the role of autophagy in the development of diabetes. Furthermore, we discuss the possible beneficial effects of selectively targeting antioxidants to mitochondria as a strategy for modulating mitochondrial function in diabetes. 相似文献
57.
Benjamin J. Espinosa Scott C. Weaver Slobodan Paessler Douglas Brining Milagros Salazar Tadeusz Kochel 《Vaccine》2009
Eastern equine encephalitis virus (EEEV) is an arthropod-borne virus associated with life-threatening encephalitis in humans, equines, birds and many other domestic animals. To investigate the suitability of the Aotus nancymaae New World owl monkey as a viable animal model for EEE candidate vaccine testing we used clinical presentation, serology, viral isolation and PCR to evaluate pathogenesis and immunity in infected animals. Monkeys were inoculated subcutaneously (SQ) or intranasally (IN) with 104 pfu of virulent EEEV and were initially followed for 45 days. While none of the animals displayed clinical signs of disease, all of the SC inoculated animals (n = 6) manifested a viremia averaging 3.2 days (±0.8 days). Likewise, serologic responses (IgM, IgG and PRNT) were observed in all SC infected animals. Interestingly, none of the IN inoculated animals (n = 6) became viremic or mounted an antibody response and no pathological abnormalities were observed in two animals that were necropsied on day 6 post-infection (p.i.) from each group. To determine if the antibodies produced by the SC inoculated animals were protective against homologous challenge, three animals from the SC group were serologically evaluated on day 253 p.i. and were administered an inoculum identical to initial challenge on day 270 p.i. A positive control group of four naïve animals was also infected as before. All of the naïve positive control animals manifested a similar viremia as observed initially, averaging 2.75 days (±0.5 days) while none of the previously challenged animals became viremic. On days 45 and 253 p.i. geometric mean PRNT titers in the SC group were 453 and 101, respectively. This study demonstrates that the Aotus nancymaae can be reproducibly infected with EEE virus and can serve as a suitable model for infection and immunogenicity for the evaluation of candidate vaccines against EEEV. 相似文献
58.
Endogenous opioid systems have been suggested to play a key role in ethanol reinforcement mechanisms and alcohol-drinking
behavior. Ethanol induces differential alterations in opioid peptide expression in brain areas of the reward circuits, which
may be linked to the reinforcing effects of ethanol. In addition, ethanol-induced alterations in opioidergic nigrostriatal
transmission could be involved in brain sensitivity to ethanol and play a role in addictive processes. The aim of this work
was to study the effects of acute ethanol administration on proenkephalin (proenk) mRNA expression in the rat substantia nigra
and caudate–putamen (CP) for up to 24 h post treatment. Male Wistar rats received ethanol (2.5 g/kg) or distilled water by
intragastric administration, and proenk mRNA expression was studied by in situ hybridization and densitometry. Ethanol transiently
increased proenk mRNA expression in the CP 1 h after drug administration. Proenk mRNA levels remained elevated 2 h post treatment
in the anterior–medial and medial–posterior regions of the CP. In contrast, ethanol decreased proenk mRNA expression in the
substantia nigra pars compacta and pars reticulata 2 h after drug exposure. Alterations in enkephalin expression in the substantia
nigra and CP in response to ethanol exposure could be involved in the mechanisms underlying brain sensitivity to the drug. 相似文献
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60.
Costanza ME Luckmann R Stoddard AM White MJ Stark JR Avrunin JS Rosal MC Clemow L 《Cancer Detection and Prevention》2007,31(3):191-198
BACKGROUND: Few interventions to increase colorectal cancer screening have used a stage of change model to promote screening adoption. None have used computer-assisted tailored telephone counseling calls. This study's purpose was to implement and evaluate stage-based computer-assisted tailored telephone counseling to promote colorectal cancer screening in a primary care population. METHODS: This randomized controlled trial used a two-stepped intervention that included a mailed booklet on colorectal cancer screening followed by computer-assisted telephone counseling that was based on the Precaution Adoption Process Model. Chart audit was used to document completion of colonoscopy, sigmoidoscopy or fecal occult blood testing. RESULTS: Record audits were completed on 2,474 (88%) of the 2,817 eligible participants. There was no significant difference in the frequency and nature of the screening tests completed in the study arms. In a sub-analysis, stages of adoption were evaluated pre- and post-telephone counseling. Over half those receiving counseling reported a change in stage towards screening adoption. CONCLUSION: Overall, the intervention did not increase colorectal screening compared to control. Two possible reasons for the absence of a screening effect include: (a) the focus of the protocol on education for most patients rather than motivation, and (b) the requirement that patients interested in screening seek further information and a referral on their own from their providers. While those receiving telephone counseling improved their stage of adoption, we cannot rule out selection bias. Stronger physician recommendation to speak with the counselors could improve call acceptance. Future colorectal screening should address these weaknesses. 相似文献