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111.

Purpose

To describe at molecular level a family with pulverulent congenital cataract associated with a CRYGC gene mutation.

Methods

One family with several affected members with pulverulent congenital cataract and 230 healthy controls were examined. Genomic DNA from leukocytes was isolated to analyze the CRYGA-D cluster, CX46, CX50 and MIP genes through high-resolution melting curve and DNA sequencing.

Results

DNA sequencing in the affected members revealed the c.143G>A mutation (p.R48H) in exon 2 of the CRYGC gene; 230 healthy controls and ten healthy relatives were also analyzed and none of them showed the c.143G>A mutation. No other polymorphisms or mutations were found to be present.

Conclusion

In the present study, we described a family with pulverulent congenital cataract that segregated the c.143G>A mutation (p.R48H) in the CRYGC gene. A few mutations have been described in the CRYGC gene in autosomal dominant cataract, none of them with pulverulent cataract making clear the clinical heterogeneity of congenital cataract. This mutation has been associated with the phenotype of congenital cataract but also is considered an SNP in the NCBI data base. Our data and previous report suggest that p.R48H could be a disease-causing mutation and not an SNP.  相似文献   
112.
Pastoralists employ different strategies to minimize the risk of losing their livelihood due to drought, disease, and other disasters. Livestock transfers have been considered critical because they provide not only a safety net during disasters but also contribute to the resilience of pastoral societies by allowing pastoralists to rebuild their herds after disasters. I examine whether and how livestock transfers serve as risk management strategies in a comparative, ethnographic study of three pastoralist communities in the Far North Region of Cameroon. The findings show that livestock transfers contribute to short-term survival of households but not long-term viability of family herds. Here I argue for a more holistic, anthropological approach that considers the social and cultural aspects of strategic decisions that individual pastoralists make when they engage in these transfers.  相似文献   
113.
Numerous taxa make up the Early Cretaceous fauna of Brazil, including Ornithocheiroidea, Tapejaridae, Thalassodromidae, Chaoyangopteridae and a purported member of Azhdarchidae. Dsungaripteridae has only been tentatively assumed to be present in the form of ‘Santanadactylusspixi. New study of NMSG SAO 251093 (a specimen referred to Thalassodromeus sethi) suggests it is a previously unknown species of dsungaripterid, Banguela oberlii, tax. nov., differing from Thalassodromeus and other pterosaurs from the Early Cretaceous of Brazil by a unique combination of characters, including an upturned jaw tip, a short dorsal mandibular symphyseal shelf (dmss), and an autapomorphic thin crest placed halfway along the fused mandibular symphysis without a keel along the ventral margin of the jaw. B. oberlii, tax. nov., is referred to Dsungaripteridae based on a dmss no longer than the ventral shelf, U-shaped caudal margin of the ventral shelf and lateral margins of the mandibular symphysis concave in dorsal view. B. oberlii, tax. nov., is the youngest known dsungaripterid, and expands known morphological diversity in the clade as well as the Early Cretaceous pterosaur fauna of South America.  相似文献   
114.
Dehydrins, which belong to group 2 LEA proteins, are a family of intrinsically unstructured plant proteins that accumulate during the late stages of embryogenesis and in response to abiotic stresses. We have previously reported that the OpsDHN1 gene, encoding an SK3-type acidic dehydrin protein from Opuntia streptacantha, contains an intron inserted within the sequence encoding the S-motif. Herein, we present an in silico analysis of intron sequences in dehydrin genes from mono- and dicotyledonous plants that reveals a preference for insertion within the nucleotide sequence encoding the S-motif. Sequence comparison of ten Dhn genes from Arabidopsis thaliana and the orthologous genes in Arabidopsis lyrata revealed that introns maintain considerable sequence identity and conserve the insertion pattern. Furthermore, syntenic regions were identified among eight orthologous genes of A. thaliana and A. lyrata, showing that correlated gene arrangements are conserved between these Arabidopsis species. Our study shows that most SKn-type dehydrins contain one intron that is conserved in phase and location; this intron is linked to the nucleotide sequence that encodes the S-motif.  相似文献   
115.
Pérez del Val, J. 2000. On the altitudinal limits of birds on Basile Peak (Bioko Island; Equatorial Guinea). Ostrich 71(1 & 2): 342.

The lower altitudinal limit of the montane avifauna in Africa has generally been set at 1 500- 800 m, corresponding to vegetation belts of the main mountain ranges of East Africa. However, much lower limits have been reported from the East Usambaras (Tanzania), Mount Cameroon, and Bioko Island. Basilé Peak is a volcano of 3 011 m which constitutes the northern half of Bioko Island. Below 400–900 m the forest has been logged and largely replaced by cocoa plantations, but the vegetation is relatively undisturbed at higher altitudes. Annual rainfall ranges between 2 000 mm and 3 500 mm. From January 1990 to July 1992 mist-nets were set at 13 standardised stations on Basilé Peak; 1 427 birds of 71 species were captured. Previous data from non-standardised mist-netting at 6 other localities, together with sight and sound records, published data, and 1 047 skins in the collections of Museo Naçional de Ciençias Naturales (Madrid), Estacion Biologica de Donaiia (Sevilla) and the Natural History Museum (Tring) were also used to compile distribution lists. From published botanical surveys, I recognised four vegetation zones: Lowland Rain Forest up to 800 m; Mountain Rain Forest at 80CL1 800 m; Araliaceus Forest 1 800–2 500 m; and Ericaceus Stands above 2 500 m. An analysis of similarity (using the index of Czechanowski) grouped 68 bird species into altitudinal classes at 200 m intervals. This suggests a division between lowland and montane birds at 800–1 000 m, broadly coinciding with the change between Lowland and Mountain Rain Forest. There does not seem to be a discrete bird community restricted to either of the upper zones (Araliaceus Forest or Ericaeus Stands), with only the Yellow Bishop Euplectes capensis restricted to the upper 500 m of the mountain. Most species which reach the summit are found in all vegetation zones, notably the endemic subspecies of the African Goshawk Accipiter tachiro lopezi. It is suggested that low temperatures, high rainfall, and in particular the seasonal distribution of rainfall, may explain the lower altitudinal limits of the montane avifauna on Bioko and on Mount Cameroon.  相似文献   
116.
Antimicrobial and antiviral activities of the fractions from Scutia buxifolia stem bark and leaves were evaluated. Best antimicrobial results occurred with the ethyl acetate (EA) and n-butanolic (NB) fractions from the leaves against Micrococcus sp. (minimal inhibitory concentration—MIC = 62.5 μg/ml), and NB fraction from stem bark and leaves against Klebsiella pneumoniae and Enterococcus faecalis (MIC = 62.5 μg/ml). The most active fractions were selected and fractioned into silica column to perform an in vitro antibiofilm assay, which evidenced subfractions EA2 and EA3 as the more active against Candida albicans (biofilm inhibitory concentration—BIC = 582 ± 0.01 μg/ml) and Staphylococcus aureus (BIC = 360 ± 0.007 μg/ml), respectively. The NB (selectivity index—SI = 25.78) and the EA (SI = 15.97) fractions from the stem bark, and the EA (SI = 14.13) fraction from the leaves exhibited a potential antiviral activity towards Herpes Simplex Virus type 1 whereas EA2 and EA3 subfractions from leaves (SI = 12.59 and 10.06, respectively), and NB2 subfraction from stem bark (SI = 12.34) maintained this good activity. Phenolic acids and flavonoids (gallic acid, chlorogenic acid, caffeic acid, rutin, isoquercitrin, quercitrin and quercetin) were identified by HPLC and may be partially responsible for the antimicrobial and antiherpes activities observed. The results obtained in this study showed that Scutia buxifolia has antibiofilm and anti-herpetic activities and that these properties are reported for the first time for this species.  相似文献   
117.
118.
Previous binding studies of antibodies that recognized a partially or fully hidden epitope suggest that insect cell-derived dengue virus undergoes structural changes at an elevated temperature. This was confirmed by our cryo-electron microscopy images of dengue virus incubated at 37°C, where viruses change their surface from smooth to rough. Here we present the cryo-electron microscopy structures of dengue virus at 37°C. Image analysis showed four classes of particles. The three-dimensional (3D) map of one of these classes, representing half of the imaged virus population, shows that the E protein shell has expanded and there is a hole at the 3-fold vertices. Fitting E protein structures into the map suggests that all of the interdimeric and some intradimeric E protein interactions are weakened. The accessibility of some previously found cryptic epitopes on this class of particles is discussed.  相似文献   
119.
One of the most important scientific challenges today is the quantitative and predictive understanding of biological function. Classical mathematical and computational approaches have been enormously successful in modeling inert matter, but they may be inadequate to address inherent features of biological systems. We address the conceptual and methodological obstacles that lie in the inverse problem in biological systems modeling. We introduce a full Bayesian approach (FBA), a theoretical framework to study biological function, in which probability distributions are conditional on biophysical information that physically resides in the biological system that is studied by the scientist.  相似文献   
120.
The goal of this study was to demonstrate the usefulness of an enzyme-linked immunosorbent assay (ELISA) for the serodiagnosis of pulmonary tuberculosis (PTB) and extrapulmonary TB (EPTB). This assay used 20 amino acid-long, non-overlapped synthetic peptides that spanned the complete Mycobacterium tuberculosis ESAT-6 and Ag85A sequences. The validation cohort consisted of 1,102 individuals who were grouped into the following five diagnostic groups: 455 patients with PTB, 60 patients with EPTB, 40 individuals with non-EPTB, 33 individuals with leprosy and 514 healthy controls. For the PTB group, two ESAT-6 peptides (12033 and 12034) had the highest sensitivity levels of 96.9% and 96.2%, respectively, and an Ag85A-peptide (29878) was the most specific (97.4%) in the PTB groups. For the EPTB group, two Ag85A peptides (11005 and 11006) were observed to have a sensitivity of 98.3% and an Ag85A-peptide (29878) was also the most specific (96.4%). When combinations of peptides were used, such as 12033 and 12034 or 11005 and 11006, 99.5% and 100% sensitivities in the PTB and EPTB groups were observed, respectively. In conclusion, for a cohort that consists entirely of individuals from Venezuela, a multi-antigen immunoassay using highly sensitive ESAT-6 and Ag85A peptides alone and in combination could be used to more rapidly diagnose PTB and EPTB infection.  相似文献   
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