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Fidelity of individual animals to breeding sites is a primary determinant of population structure. The degree and scale of philopatry in a population reflect the fitness effects of social facilitation, ecological adaptation and optimal inbreeding. Patterns of breeding-site movement and fidelity are functions of social structure and are frequently sex biased. We report on a female humpback whale (Megaptera novaeangliae) first identified by natural markings off Brazil that subsequently was photographed off Madagascar. The minimum travel distance between these locations is greater than 9800 km, approximately 4000 km longer than any previously reported movement between breeding grounds, more than twice the species' typical seasonal migratory distance and the longest documented movement by a mammal. It is unexpected to find this exceptional long-distance movement between breeding groups by a female, as models of philopatry suggest that male mammals move more frequently or over longer distances in search of mating opportunities. While such movement may be advantageous, especially in changeable or unpredictable circumstances, it is not possible to unambiguously ascribe causality to this rare observation. This finding illustrates the behavioural flexibility in movement patterns that may be demonstrated within a typically philopatric species.  相似文献   
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With the aim of creating new bisubstrate inhibitors of protein farnesyltransferase (FTase), new carboxylic farnesyl pyrophosphate analogues have been designed and synthesized. The original structures are built around three elements: a prenyl moiety, a 1,4-diacid motif and an imidazole ring. All the compounds were evaluated for their ability to inhibit FTase and compared with the corresponding derivatives lacking the imidazole ring, synthesized for that purpose. These new compounds are not bisubstrate inhibitors probably because the imidazole ring is not in the right position to interact with the zinc atom. However these derivatives display FPP competitive inhibition with a good activity in the carboxylic farnesyl pyrophosphate analogues series.  相似文献   
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Background

All four serotypes of dengue virus are endemic in Indonesia, where the population at risk for infection exceeds 200 million people. Despite continuous control efforts that were initiated more than four decades ago, Indonesia still suffers from multi-annual cycles of dengue outbreak and dengue remains as a major public health problem. Dengue vaccines have been viewed as a promising solution for controlling dengue in Indonesia, but thus far its potential acceptability has not been assessed.

Methodology/Principal Findings

We conducted a household survey in the city of Bandung, Indonesia by administering a questionnaire to examine (i) acceptance of a hypothetical pediatric dengue vaccine; (ii) participant''s willingness-to-pay (WTP) for the vaccine, had it not been provided for free; and (iii) whether people think vector control would be unnecessary if the vaccine was available. A proportional odds model and an interval regression model were employed to identify determinants of acceptance and WTP, respectively. We demonstrated that out of 500 heads of household being interviewed, 94.2% would agree to vaccinate their children with the vaccine. Of all participants, 94.6% were willing to pay for the vaccine with a median WTP of US$1.94. In addition, 7.2% stated that vector control would not be necessary had there been a dengue vaccination program.

Conclusions/Significance

Our results suggest that future dengue vaccines can have a very high uptake even when delivered through the private market. This, however, can be influenced by vaccine characteristics and price. In addition, reduction in community vector control efforts may be observed following vaccine introduction but its potential impact in the transmission of dengue and other vector-borne diseases requires further study.  相似文献   
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IntroductionPure Neural Leprosy (PNL) is a rare clinical form of leprosy in which patients do not present with the classical skin lesions but have a high burden of the disability associated with the disease. Clinical characteristics and follow up of patients in PNL are still poorly described in the literature.ObjectiveThis paper aims to describe the clinical, electrophysiological and histopathological characteristics of PNL patients, as well as their evolution after multidrug therapy (MDT).MethodsFifty-two PNL patients were selected. Clinical, nerve conduction studies (NCS), histopathological and anti-PGL-1serology were evaluated. Patients were also assessed monthly during the MDT. At the end of the MDT, all of the patients had a new neurological examination and 44 were submitted to another NCS.ResultsParesthesia was the complaint most frequently reported by patients, and in the neurological examination the most common pattern observed was impairment in sensory and motor examination and a mononeuropathy multiplex. Painful nerve enlargement, a classical symptom of leprosy neuropathy, was observed in a minority of patients and in the motor NCS axonal injuries, alone or in combination with demyelinating features, were the most commonly observed. 88% of the patients did not present any leprosy reaction during MDT. There was no statistically significant difference between the neurological examinations, nor the NCS pattern, performed before and after the MDT.DiscussionThe classical hallmarks of leprosy neuropathy are not always present in PNL making the diagnosis even more challenging. Nerve biopsy is an important tool for PNL diagnosis as it may guide therapeutic decisions. This paper highlights unique characteristics of PNL in the spectrum of leprosy in an attempt to facilitate the diagnosis and management of these patients.  相似文献   
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