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1.
To better understand breeding conditions to promote reproduction in captive kori bustards, fundamental endocrine studies measuring fecal androgen metabolites in male and female kori bustards were conducted. Feces collected weekly from males and females were analyzed for testosterone using enzyme‐linked immunoassay. Results from adult males (n = 5), adult females (n = 10), immature males (n = 10), and immature females (n = 10) revealed seasonally elevated testosterone concentrations in fertile, but not nonfertile adult males and females (P > 0.05). Adult females that were not maintained in a breeding group, or that did not produce eggs, did not demonstrate increases in testosterone compared to egg laying counterparts. In males, but not females, seasonal testosterone increases were accompanied by weight gain. Peaks in male fecal androgen metabolites ranged from 10‐ to 22‐fold higher than nonbreeding season (181.5 ± 19.1 vs. 17.0 ± 0.94 ng/g; P < 0.05). Mean breeding season values for adult males were 83.6 ± 6.1 ng/g vs. nonbreeding season values of 12.3 ± 0.73 ng/g (P < 0.05). In females, average breeding season testosterone concentrations were approximately 4‐fold higher than nonbreeding season (55.9 ± 6.0 vs. 14.5 ± 1.8 ng/g), with peaks 10‐ to 30‐fold higher. Results show that noninvasive fecal androgen metabolite analysis can provide a means of predicting fertility potential of male and female kori bustards and might be utilized to assess effects of modifying captive environments to promote reproduction in this species. Zoo Biol. 32:54‐62, 2013. © 2012 Wiley Periodicals, Inc.  相似文献   
2.

Background and methods

Human metapneumovirus (hMPV) is a recently discovered respiratory virus associated with bronchiolitis, pneumonia, croup and exacerbations of asthma. Since respiratory viruses are frequently detected in patients with acute exacerbations of COPD (AE-COPD) it was our aim to investigate the frequency of hMPV detection in a prospective cohort of hospitalized patients with AE-COPD compared to patients with stable COPD and to smokers without by means of quantitative real-time RT-PCR.

Results

We analysed nasal lavage and induced sputum of 130 patients with AE-COPD, 65 patients with stable COPD and 34 smokers without COPD. HMPV was detected in 3/130 (2.3%) AE-COPD patients with a mean of 6.5 × 105 viral copies/ml in nasal lavage and 1.88 × 105 viral copies/ml in induced sputum. It was not found in patients with stable COPD or smokers without COPD.

Conclusion

HMPV is only found in a very small number of patients with AE-COPD. However it should be considered as a further possible viral trigger of AE-COPD because asymptomatic carriage is unlikely.  相似文献   
3.
Voltage gated potassium channels have been extensively studied in relation to cancer. In this review, we will focus on the role of two potassium channels, Ether à-go-go (Eag), Human ether à-go-go related gene (HERG), in cancer and their potential therapeutic utility in the treatment of cancer. Eag and HERG are expressed in cancers of various organs and have been implicated in cell cycle progression and proliferation of cancer cells. Inhibition of these channels has been shown to reduce proliferation both in vitro and vivo studies identifying potassium channel modulators as putative inhibitors of tumour progression. Eag channels in view of their restricted expression in normal tissue may emerge as novel tumour biomarkers.  相似文献   
4.
The self-assembly of hybrid diblock copolymers composed of poly(HPMA) and beta-sheet peptide P11 (CH(3)CO-QQRFQWQFEQQ-NH(2)) blocks was investigated. Copolymers were synthesized via thiol-maleimide coupling reaction, by conjugation of semitelechelic poly(HPMA)-SH with maleimide-modified beta-sheet peptide. As expected, CD and CR binding studies showed that the peptide block imposed its beta-sheet structural arrangement on the structure of diblock copolymers. TEM and AFM proved that peptide and these copolymers had the ability to self-assemble into fibrils.  相似文献   
5.
Salicylic acid is an important signalling molecule involved in both locally and systemically induced disease resistance responses. Recent advances in our understanding of plant defence signalling have revealed that plants employ a network of signal transduction pathways, some of which are independent of salicylic acid. Evidence is emerging that jasmonic acid and ethylene play key roles in these salicylic acid-independent pathways. Cross-talk between the salicylic acid-dependent and the salicylic acid-independent pathways provides great regulatory potential for activating multiple resistance mechanisms in varying combinations.  相似文献   
6.

Background  

In Arabidopsis, ETO1 (ETHYLENE-OVERPRODUCER1) is a negative regulator of ethylene evolution by interacting with AtACS5, an isoform of the rate-limiting enzyme, 1-aminocyclopropane-1-carboxylate synthases (ACC synthase or ACS), in ethylene biosynthetic pathway. ETO1 directly inhibits the enzymatic activity of AtACS5. In addition, a specific interaction between ETO1 and AtCUL3, a constituent of a new type of E3 ubiquitin ligase complex, suggests the molecular mechanism in promoting AtACS5 degradation by the proteasome-dependent pathway. Because orthologous sequences to ETO1 are found in many plant species including tomato, we transformed tomato with Arabidopsis ETO1 to evaluate its ability to suppress ethylene production in tomato fruits.  相似文献   
7.

Background

Due partly to physicians’ unawareness, many adults with Pompe disease are diagnosed with great delay. Besides, it is not well known which factors influence the rate of disease progression, and thus disease outcome. We delineated the specific clinical features of Pompe disease in adults, and mapped out the distribution and severity of muscle weakness, and the sequence of involvement of the individual muscle groups. Furthermore, we defined the natural disease course and identified prognostic factors for disease progression.

Methods

We conducted a single-center, prospective, observational study. Muscle strength (manual muscle testing, and hand-held dynamometry), muscle function (quick motor function test), and pulmonary function (forced vital capacity in sitting and supine positions) were assessed every 3–6 months and analyzed using repeated-measures ANOVA.

Results

Between October 2004 and August 2009, 94 patients aged between 25 and 75 years were included in the study. Although skeletal muscle weakness was typically distributed in a limb-girdle pattern, many patients had unfamiliar features such as ptosis (23%), bulbar weakness (28%), and scapular winging (33%). During follow-up (average 1.6 years, range 0.5-4.2 years), skeletal muscle strength deteriorated significantly (mean declines of ?1.3% point/year for manual muscle testing and of ?2.6% points/year for hand-held dynamometry; both p<0.001). Longer disease duration (>15 years) and pulmonary involvement (forced vital capacity in sitting position <80%) at study entry predicted faster decline. On average, forced vital capacity in supine position deteriorated by 1.3% points per year (p=0.02). Decline in pulmonary function was consistent across subgroups. Ten percent of patients declined unexpectedly fast.

Conclusions

Recognizing patterns of common and less familiar characteristics in adults with Pompe disease facilitates timely diagnosis. Longer disease duration and reduced pulmonary function stand out as predictors of rapid disease progression, and aid in deciding whether to initiate enzyme replacement therapy, or when.
  相似文献   
8.
Although critical to the conservation of white rhinoceros, captive breeding has proven challenging because of the poor and irregular reproductive health of many captive rhinos, and social interactions may play a significant role. This research investigated the social and spatial relationships of two captive groups of southern white rhinoceros (Ceratotherium simum simum) by examining the frequency of companion changes, the number of space maintenance vocalizations made per hour by each reproductively mature female, and dominant/subordinate interactions. The observed captive rhinos did not change their companionships during the study. They exhibited space maintenance vocalizations and display greater than once per hour, particularly when feeding. Females housed with four calves on 0.033 km2 exhibited space maintenance vocalizations more frequently (X±SE = 6.19±0.199/hr) than females housed with one calf and more space (0.06 km2, X±SE = 0.55±0.182/hr) and females housed without calves and more space (0.65 km2, X±SE = 1.90±0.086/hr). Wider separation of food piles and of females with young calves is suggested to reduce the interpreted spatial stress. The presence of a large number of rhinos in restricted captive space resulted in the formation of herds with dominance hierarchies that were enforced during competition for food and shade. The most subordinate rhino in each of the herds exhibited unusual behaviors such as dung‐kicking and nonestrus urine squirting, and neither has ever reproduced. Suppression of subordinate rhinos might lead to social stress that could negatively impact reproductive success. Zoo Biol 26:487–502, 2007. © 2007 Wiley‐Liss, Inc.  相似文献   
9.

Background  

Parathyroid hormone (PTH) and PTH-related peptide (PTHrP) belong to a family of endocrine factors that share a highly conserved N-terminal region (amino acids 1-34) and play key roles in calcium homeostasis, bone formation and skeletal development. Recently, PTH-like peptide (PTH-L) was identified in teleost fish raising questions about the evolution of these proteins. Although PTH and PTHrP have been intensively studied in mammals their function in other vertebrates is poorly documented. Amphibians and birds occupy unique phylogenetic positions, the former at the transition of aquatic to terrestrial life and the latter at the transition to homeothermy. Moreover, both organisms have characteristics indicative of a complex system in calcium regulation. This study investigated PTH family evolution in vertebrates with special emphasis on Xenopus and chicken.  相似文献   
10.
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