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991.
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Background

Selection criteria are important for analyzing domestication of perennial plant species, which experience a selection pressure throughout several human generations. We analyze the preferred morphological characteristics of Crescentia cujete fruits, which are used as bowls by the Maya of Yucatan, according to the uses they are given and the phenotypic consequences of artificial selection between one wild and three domesticated varieties.

Methods

We performed 40 semi-structured interviews in seven communities. We calculated Sutrop’s salience index (S) of five classes of ceremonial and daily life uses, and of each item from the two most salient classes. We sampled 238 bowls at homes of people interviewed and compared their shape, volume and thickness with 139 fruits collected in homegardens and 179 from the wild. Morphology of varieties was assessed in fruit (n?=?114 trees) and vegetative characters (n?=?136 trees). Differences between varieties were evaluated through linear discriminant analysis (LDA).

Results

Use of bowls as containers for the Day of the Dead offerings was the most salient class (S?=?0.489) with chocolate as its most salient beverage (S?=?0.491), followed by consumption of daily beverages (S?=?0.423), especially maize-based pozol (S?=?0.412). The sacred saka’ and balche' are offered in different sized bowls during agricultural and domestic rituals. Roundness was the most relevant character for these uses, as bowls from households showed a strong selection towards round shapes compared with wild and homegarden fruits. Larger fruits from domesticated varieties were also preferred over small wild fruits, although in the household different sizes of the domesticated varieties are useful. LDA separated wild from domesticated trees (p?<?0.001) according to both fruit and vegetative variables, but domesticated varieties were not different among themselves.

Conclusions

The association between C. cujete bowls and traditional beverages in ritual and daily life situations has driven for centuries the selection of preferred fruit morphology in this tree. Selection of fruit roundness and volume has allowed for the differentiation between the wild variety and the three domesticated ones, counteracting gene flow among them. By choosing the best fruits from domesticated varieties propagated in homegardens, the Maya people model the domestication process of this important tree in their culture.
  相似文献   
994.
This article documents the addition of 83 microsatellite marker loci and 96 pairs of single‐nucleotide polymorphism (SNP) sequencing primers to the Molecular Ecology Resources Database. Loci were developed for the following species: Bembidion lampros, Inimicus japonicus, Lymnaea stagnalis, Panopea abbreviata, Pentadesma butyracea, Sycoscapter hirticola and Thanatephorus cucumeris (anamorph: Rhizoctonia solani). These loci were cross‐tested on the following species: Pentadesma grandifolia and Pentadesma reyndersii. This article also documents the addition of 96 sequencing primer pairs and 88 allele‐specific primers or probes for Plutella xylostella.  相似文献   
995.
996.

Background

Combined idiopathic pulmonary fibrosis (IPF) with pulmonary emphysema (CPFE) is a syndrome with a characteristic presentation of upper lobe emphysema and lower lobe fibrosis. While CPFE is a strong determinant of secondary precapillary pulmonary hypertension (PH), there is limited evidence regarding the management of patients with CPFE and PH.

Case presentation

A 63 year-old male presented in 2006 with dyspnoea on exertion having quit smoking in 2003. Clinical examination, together with high resolution computed tomography, bronchoalveolar lavage, and echocardiographic assessments, suggested a diagnosis of CPFE without PH. In 2007, the patient received intravenous cyclophosphamide, N-acetylcysteine, and short-term anticoagulation treatment. Due to remission of acute exacerbations, the patient received triple combination therapy (prednisone, N-acetylcysteine and azathioprine). Upon progressive clinical worsening, long-term supplemental oxygen therapy was initiated in 2009. Repeated right heart catheterisation in 2011 confirmed PH and worsening pulmonary haemodynamics, and off-label ambrisentan therapy was initiated. Dyspnoea remained at follow-up, although significant haemodynamic improvement was observed.

Conclusion

CFPE is a distinct but under-recognized and common syndrome with a characteristic presentation. Further studies are needed to ascertain the etiology, morbidity, and mortality of CPEF with or without PH, and to evaluate novel management options.
  相似文献   
997.

Background

The diagnosis of idiopathic pulmonary fibrosis can be quite challenging, even after careful clinical evaluation, imaging and pathological tests. This case report intends to demonstrate and discuss these difficulties, especially those concerning the differential diagnosis with chronic hypersensitivity pneumonitis.

Case presentation

A 58-year-old white male presented with shortness of breath, dry cough, fatigue and weight loss for two months. He was a former smoker and had regular exposure to a parakeet and poultry. Physical examination revealed bilateral basal crackles and chest imaging showed subpleural cystic lesions and traction bronchiectasis with a right side and upper level predominance. Auto-antibodies and IgG immunoglobulins to parakeet and fungal proteins were negative. Lung function tests displayed moderate restriction, low diffusion capacity and resting hypoxaemia. Bronchoalveolar lavage showed increased lymphocytes (28%) and neutrophils (12%) and surgical lung biopsy was compatible with a pattern of usual interstitial pneumonia. According to the possibility of either idiopathic pulmonary fibrosis or chronic hypersensitivity pneumonitis, treatment included prednisolone, azathioprine, acetylcysteine and avoidance of contact with the parakeet, but there was an unfavorable response and the patient was subsequently referred for lung transplant.

Conclusion

Chronic hypersensitivity pneumonitis and idiopathic pulmonary fibrosis can present with the same clinical and radiological manifestations In this case, despite careful evaluation, no definite diagnosis could be achieved.
  相似文献   
998.
999.
Hypoxic/ischemic injury to kidney is a frequently encountered clinical problem with limited therapeutic options. Since microRNAs are differentially involved in hypoxic/ischemic events and δ-opioid receptor (DOR) activation is known to protect against hypoxic/ischemic injury, we speculated on the involvement of DOR activation in altering the microRNA (miRNA) expression in kidney under hypoxic condition. We selected 31 miRNAs based on microarray data for quantitative PCR analysis. Among them, 14 miRNAs were significantly altered after prolonged hypoxia, DOR activation or a combination of both. We found that 1) DOR activation alters miRNA expression profiles in normoxic conditions; 2) hypoxia differentially alters miRNA expression depending on the duration of hypoxia; and 3) DOR activation can modify hypoxia-induced changes in miRNA expression. For example, 10-day hypoxia reduced the level of miR-212 by over 70%, while DOR activation could mimic such reduction even in normoxic kidney. In contrast, the same stress increased miR-29a by >100%, which was reversed following DOR activation. These first data suggest that hypoxia comprehensively modifies the miRNA profile within the kidney, which can be mimicked or modified by DOR activation. Ascertaining the targeted pathways that regulate the diverse cellular and molecular functions of miRNA may provide new insights into potential therapies for hypoxic/ischemic injury of the kidney.  相似文献   
1000.
The changing profile of infection over time for Human Parechoviruses (HPeVs) is not well known and no detailed study has been reported to date in China. This investigation on HPeV infection in hospitalized children in Lanzhou, China revealed variations in epidemiological characteristics after a three-year interval. To assess the changes that had occurred, epidemiological and clinical characteristics of HPeVs were characterized and compared with previously reported data by our group. A comparable positivity rate (25.3%, 73/289) was revealed after the three-year interval with the majority of the infected children (95.9%, 70/73) being younger than two years of age. While a temporal change in the seasonal distribution was noted in the current study, HPeVs were more frequently detected during July to November compared to September to December in the previous study. Changes in HPeV genotypes patterns, a temporal change in the prevalence of HPeV1, a younger susceptible age to HPeV3 compared with HPeV1 and a tendency of older children to be infected with HPeV4 are in contrast to our previous report. HPeV2, a rarely reported genotype, was identified for the first time in China. In addition, an exclusive trinucleotide (GAT) insertion in the HPeV4 nucleotide sequence was identified. However, the profiles of co-infection with other enteric related viruses were similar to our previous findings. In summary, these data suggest temporal variation in the seasonal distribution of HPeV and changing patterns of HPeV genotypes over time in the study region.  相似文献   
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