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201.
Tali Cassidy Caitlin M. Worrell Kristen Little Aishya Prakash Inakhi Patra Jonathan Rout LeAnne M. Fox 《PLoS neglected tropical diseases》2016,10(2)
Background
Globally 68 million people are infected with lymphatic filariasis (LF), 17 million of whom have lymphedema. This study explores the effects of a lymphedema management program in Odisha State, India on morbidity and psychosocial effects associated with lymphedema.Methodology/Principal Findings
Focus groups were held with patients (eight groups, separated by gender), their family members (eight groups), community members (four groups) and program volunteers (four groups) who had participated in a lymphedema management program for the past three years. Significant social, physical, and economic difficulties were described by patients and family members, including marriageability, social stigma, and lost workdays. However, the positive impact of the lymphedema management program was also emphasized, and many family and community members indicated that community members were accepting of patients and had some improved understanding of the etiology of the disease. Program volunteers and community members stressed the role that the program had played in educating people, though interestingly, local explanations and treatments appear to coexist with knowledge of biomedical treatments and the mosquito vector.Conclusions/Significance
Local and biomedical understandings of disease can co-exist and do not preclude individuals from participating in biomedical interventions, specifically lymphedema management for those with lymphatic filariasis. There is a continued need for gender-specific psychosocial support groups to address issues particular to men and women as well as a continued need for improved economic opportunities for LF-affected patients. There is an urgent need to scale up LF-related morbidity management programs to reduce the suffering of people affected by LF. 相似文献202.
203.
Howe GT; Bucciaglia PA; Hackett WP; Furnier GR; Cordonnier-Pratt MM; Gardner G 《Molecular biology and evolution》1998,15(2):160-175
The phytochrome photoreceptors play important roles in the photoperiodic
control of vegetative bud set, growth cessation, dormancy induction, and
cold-hardiness in trees. Interestingly, ecotypic differences in
photoperiodic responses are observed in many temperate- zone tree species.
Northern and southern ecotypes of black cottonwood (Populus trichocarpa
Torr. & Gray), for example, exhibit marked differences in the timing of
short-day-induced bud set and growth cessation, and these responses are
controlled by phytochrome. Therefore, as a first step toward determining
the molecular genetic basis of photoperiodic ecotypes in trees, we
characterized the phytochrome gene (PHY) family in black cottonwood. We
recovered fragments of one PHYA and two PHYB using PCR-based cloning and by
screening a genomic library. Results from Southern analyses confirmed that
black cottonwood has one PHYA locus and two PHYB loci, which we arbitrarily
designated PHYB1 and PHYB2. Phylogenetic analyses which included PHY from
black cottonwood, Arabidopsis thaliana and tomato (Solanum lycopersicum)
suggest that the PHYB/D duplications in these species occurred
independently. When Southern blots were probed with PHYC, PHYE, and PHYE
heterologous probes, the strongest bands that we detected were those of
black cottonwood PHYA and/or PHYB. These results suggest that black
cottonwood lacks members of the PHYC/F and PHYE subfamilies. Although black
cottonwood could contain additional PHY that are distantly related to known
angiosperm PHY, our results imply that the PHY family of black cottonwood
is less complex than that of other well-characterized dicot species such as
Arabidopsis and tomato. Based on Southern analyses of five black cottonwood
genotypes representing three photoperiodic ecotypes, substantial
polymorphism was detected for at least one of the PHYB loci but not for the
PHYA locus. The novel character of the PHY family in black cottonwood, as
well as the differences in polymorphism we observed between the PHYA and
PHYB subfamilies, indicates that a number of fundamental macro- and
microevolutionary questions remain to be answered about the PHY family in
dicots.
相似文献
204.
Phaseolus aureus Roxb. was exposed to Hg and Cd separately at different stages/ages of its development, viz. seed germination stage and seedling stages (4th and 6th day). The responses, besides being metal specific, were also age-dependent.
The root growth study at germination stage treatment (GST) revealed Hg to be more toxic than Cd, but, in contrast, at seedling
stage treatment (SST) with seedlings more than 5 days old, while Cd killed all the seedlings at 30 μM concentration, Hg did
not even at 200 μM. Among the enzymes studied, catalase showed greater metal specific and age-dependent responses than the
peroxidases. Both the metals significantly increased the levels of chlorophylls and carotenoids at GST (25 μM Hg/Cd) and 4th
day SST (20 μM Hg/Cd), but not at 6th day SST (20 μM Hg/Cd). The photosynthetic O2 evolution rate expressed as per unit chlorophyll (chl) decreased irrespective of the treatment stages, and also the metals;
however, when expressed as per unit f. w., it was inhibited only at 6th day SST, exclusively by Cd. It seems that plants,
unlike animals, are capable of facing challenges of metals more at younger than at older stages of their development, probably
by mechanisms very different from those genetically controlled. 相似文献
205.
Heidi J. Chial Michael P. Rout Thomas H. Giddings Jr. Mark Winey 《The Journal of cell biology》1998,143(7):1789-1800
We report a novel connection between nuclear pore complexes (NPCs) and spindle pole bodies (SPBs) revealed by our studies of the Saccharomyces cerevisiae NDC1 gene. Although both NPCs and SPBs are embedded in the nuclear envelope (NE) in yeast, their known functions are quite distinct. Previous work demonstrated that NDC1 function is required for proper SPB duplication (Winey, M., M.A. Hoyt, C. Chan, L. Goetsch, D. Botstein, and B. Byers. 1993. J. Cell Biol. 122:743–751). Here, we show that Ndc1p is a membrane protein of the NE that localizes to both NPCs and SPBs. Indirect immunofluorescence microscopy shows that Ndc1p displays punctate, nuclear peripheral localization that colocalizes with a known NPC component, Nup49p. Additionally, distinct spots of Ndc1p localization colocalize with a known SPB component, Spc42p. Immunoelectron microscopy shows that Ndc1p localizes to the regions of NPCs and SPBs that interact with the NE. The NPCs in ndc1-1 mutant cells appear to function normally at the nonpermissive temperature. Finally, we have found that a deletion of POM152, which encodes an abundant but nonessential nucleoporin, suppresses the SPB duplication defect associated with a mutation in the NDC1 gene. We show that Ndc1p is a shared component of NPCs and SPBs and propose a shared function in the assembly of these organelles into the NE. 相似文献
206.
We present two NMR experiments, (3,2)D HNHA and (3,2)D HNHB, for rapid and accurate measurement of 3J(H N-H alpha) and 3J(N-H beta) coupling constants in polypeptides based on the principle of G-matrix Fourier transform NMR spectroscopy and quantitative J-correlation. These experiments, which facilitate fast acquisition of three-dimensional data with high spectral/digital resolution and chemical shift dispersion, will provide renewed opportunities to utilize them for sequence specific resonance assignments, estimation/characterization of secondary structure with/without prior knowledge of resonance assignments, stereospecific assignment of prochiral groups and 3D structure determination, refinement and validation. Taken together, these experiments have a wide range of applications from structural genomics projects to studying structure and folding in polypeptides. 相似文献
207.
Dipankar Chaudhuri Nikhil Baban Ghate Shampa Deb Sourav Panja Rhitajit Sarkar Jayashree Rout Nripendranath Mandal 《Biological research》2014,47(1)
Background
Unstable generation of free radicals in the body are responsible for many degenerative diseases. A bloom forming algae Euglena tuba growing abundantly in the aquatic habitats of Cachar district in the state of Assam in North-East India was analysed for its phytochemical contents, antioxidant activity as well as free radical scavenging potentials.Results
Based on the ability of the extract in ABTS•+ radical cation inhibition and Fe3+ reducing power, the obtained results revealed the prominent antioxidant activity of the algae, with high correlation coefficient of its TEAC values to the respective phenolic and flavonoid contents. The extract had shown its scavenging activity for different free radicals and 41.89 ± 0.41 μg/ml, 5.83 ± 0.07 μg/ml, 278.46 ± 15.02 μg/ml and 223.25 ± 4.19 μg/ml were determined as the IC50 values for hydroxyl, superoxide, nitric oxide and hypochlorous acid respectively, which are lower than that of the corresponding reference standards. The phytochemical analysis also revealed that the phenolics, flavonoids, alkaloids, tannins and carbohydrates are present in adequate amount in the extract which was confirmed by HPLC analysis.Conclusions
The results showed that 70% methanol extract of the algae possesses excellent antioxidant and free radical scavenging properties. 相似文献208.
Bud break and multiple shoots were induced in apical and axillary meristems derived from 10-d old seedlings of Madhuca longifolia var. latifolia on Murashige and Skoog (MS) medium supplemented with 1.0 mg/l N6-benzyladenine (BA) singly or in combinatiobn with 1-naphthalene acetic acid (NAA), indole-3-acetic acid (IAA) and indole-3-butyric acid (IBA). Excised shoots were rooted on half-strength MS with IBA (1.0 mg/l) after 18d of culture. Regenerated plantlets were acclimatized and successfully transferred to soil.Abbreviations BA
N6 benzyladenine
- KN
kinetin
- ADS
adenine sulphate
- IBA
indole-3-butyric acid
- IAA
indole3-acetic acid
- NAA
1-naphthaleneacetic acid
- MS
Murashige and Skoog (1962) medium 相似文献
209.
Optimization of primer screening for evaluation of genetic relationship in 34 cultivars of rose through random amplified polymorphic
DNA (RAPD) markers was investigated. Four series of decamer primers were used for screening and optimization of RAPD analysis
between which A and N series performed good amplification of fragments as compared with other series. The primers OPN-07 and
OPN-15 produced maximum number of DNA fragments in Rosa hybrida cv. Anuraag. Some primer either did not produce amplification or produced very poor amplification. Further, ten selected
primers were used for genetic analysis of 34 rose cultivars. The primer OPN-15 amplified 21 fragments in all cultivars tested.
A total of 162 distinct DNA fragments (bands) ranging from 100 to 3400 base pairs were amplified by using 10 selected random
primers. The cluster analysis indicated that these rose cultivars formed nine clusters. 相似文献