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51.
Merzlyak MN Chivkunova OB Solovchenko AE Naqvi KR 《Journal of experimental botany》2008,59(14):3903-3911
The optical properties of leaves from five species, Norway maple (Acer platanoides L.), cotoneaster (Cotoneaster alaunica Golite), hazel (Corylus avellana L.), Siberian dogwood (Cornus alba L.), and Virginia creeper (Parthenocissus quinquefolia (L.) Planch.), differing in pigment composition and at different stages of ontogenesis, were studied. Anthocyanin absorption maxima in vivo, as estimated with spectrophotometry of intact anthocyanic versus acyanic leaves and microspectrophotometry of vacuoles in the leaf cross-sections, were found between 537 nm and 542 nm, showing a red shift of 5-20 nm compared with the corresponding maxima in acidic water-methanol extracts. In non-senescent leaves, strong anthocyanin absorption was found between 500 nm and 600 nm (with a 70-80 nm apparent bandwidth). By and large, absorption by anthocyanin in leaves followed a modified form of the Lambert-Beer law, showing a linear trend up to a content of nearly 50 nmol cm(-2), and permitting thereby a non-invasive determination of anthocyanin content. The apparent specific absorption coefficients of anthocyanins at 550 nm showed no substantial dependence on the species. Anthocyanin contribution to total light absorption at 550 nm was followed in maple leaves in the course of autumn senescence. Photoprotection by vacuolar anthocyanins is discussed with special regard to their distribution within a leaf; radiation screening by anthocyanins predominantly localized in the epidermal cells in A. platanoides and C. avellana leaves was also evaluated. 相似文献
52.
Background
In August 2006 a major epidemic of bluetongue virus serotype 8 (BTV8) started off in North-West Europe. In the course of 2007 it became evident that BTV8 had survived the winter in North-West Europe, re-emerged and spread exponentially. Recently, the European Union decided to start vaccination against BTV8. In order to improve the understanding of the epidemiological situation, it was necessary to execute a cross-sectional serological study at the end of the BT vector season. Cattle were the target species for cross-sectional serological studies in Europe at the end of 2006 and 2007. However, there was no information on the BTV8-seroprevalence in sheep and goats. 相似文献53.
Azeem Z Jelani M Naz G Tariq M Wasif N Kamran-Ul-Hassan Naqvi S Ayub M Yasinzai M Amin-Ud-Din M Wali A Ali G Chishti MS Ahmad W 《Human genetics》2008,123(5):515-519
Autosomal recessive hypotrichosis (LAH3) is a rare hair disorder characterized by sparse hair on scalp and the rest of the
body of affected individuals. Recently mutations in a G protein-coupled receptor gene, P2RY5, located at LAH3 locus, have been reported in several families with autosomal recessive hypotrichosis simplex and woolly
hair. For the present study, 22 Pakistani families with autosomal recessive hypotrichosis were enrolled. Genotyping using
microsatellite markers linked to three autosomal recessive forms of hypotrichosis (LAH1, LAH2, LAH3) showed the linkage of
2 families to the LAH2 locus and 14 to the LAH3 locus. The remaining 6 families were not linked to any of the three loci.
Families linked to LAH3 locus were further subjected to screening of the P2RY5 gene with direct DNA sequencing. Three previously reported variants, c.69insCATG (p.24insHfs52), c.188A > T (p.D63V) and
c.565G > A (p.E189K) were observed in eight families. Four novel nonsynonymous sequence variants, c.8G > C (p.S3T), c.36insA
(p.D13RfsX16), c.160insA (p.N54TfsX58) and c.436G > A (p.G146R) were found to segregate within six families.
Z. Azeem, M. Jelani, G. Naz, M. Tariq, N. Wasif, S. Kamran-ul-Hassan Naqvi contributed equally to this work. 相似文献
54.
Tabassum Naqvi Trang T Duong Gihan Hashem Momotoshi Shiga Qin Zhang Sunil Kapila 《Arthritis research & therapy》2004,7(1):R1
Diseases of specific fibrocartilaginous joints are especially common in women of reproductive age, suggesting that female
hormones contribute to their etiopathogenesis. Previously, we showed that relaxin dose-dependently induces matrix metalloproteinase
(MMP) expression in isolated joint fibrocartilaginous cells. Here we determined the effects of relaxin with or without β-estradiol
on the modulation of MMPs in joint fibrocartilaginous explants, and assessed the contribution of these proteinases to the
loss of collagen and glycosaminoglycan (GAG) in this tissue. Fibrocartilaginous discs from temporomandibular joints of female
rabbits were cultured in medium alone or in medium containing relaxin (0.1 ng/ml) or β-estradiol (20 ng/ml) or relaxin plus
β-estradiol. Additional experiments were done in the presence of the MMP inhibitor GM6001 or its control analog. After 48
hours of culture, the medium was assayed for MMPs and the discs were analyzed for collagen and GAG concentrations. Relaxin
and β-estradiol plus relaxin induced the MMPs collagenase-1 and stromelysin-1 in fibrocartilaginous explants – a finding similar
to that which we observed in pubic symphysis fibrocartilage, but not in articular cartilage explants. The induction of these
proteinases by relaxin or β-estradiol plus relaxin was accompanied by a loss of GAGs and collagen in joint fibrocartilage.
None of the hormone treatments altered the synthesis of GAGs, suggesting that the loss of this matrix molecule probably resulted
from increased matrix degradation. Indeed, fibrocartilaginous explants cultured in the presence of GM6001 showed an inhibition
of relaxin-induced and β-estradiol plus relaxin-induced collagenase and stromelysin activities to control baseline levels
that were accompanied by the maintenance of collagen or GAG content at control levels. These findings show for the first time
that relaxin has degradative effects on non-reproductive synovial joint fibrocartilaginous tissue and provide evidence for
a link between relaxin, MMPs, and matrix degradation. 相似文献
55.
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57.
Phosphamidon intoxication (2 mg/kg body wt./day for 7 days) inhibited SOD activity, but enhanced the lipid peroxidation in various CNS regions. Administration of cithiolone (8 mg/kg body wt./day, ip for 7 days), however, elevated SOD activity and depleted lipid peroxidation. Interestingly, no significant change was observed either in SOD activity or in lipid peroxidation following simultaneous administration of phosphamidon and cithiolone. 相似文献
58.
Perveen Sumera Khan Tehmina Ahsan Shaheen Humaira Naz Rabia Hyder Muhammad Zeeshan Ijaz Bushra Naqvi S. M. Saqlan Yasmin Tayyaba 《In vitro cellular & developmental biology. Plant》2021,57(6):907-922
In Vitro Cellular & Developmental Biology - Plant - The OsRGLP1 gene was overexpressed under the control of CaMV 35S promoter in tomato (Solanum lycopersicum L.) plants using... 相似文献
59.
A study was conducted to assess the rhythmic pattern of physiological parameter in Malpura ewes to adapt to cold stress in a semi-arid tropical environment. Eighteen adult Malpura ewes were selected for the present study. These ewes were randomly allocated into two groups: GI (Open shed; n=9) and GII (Protected; n=9). The study was conducted for a period of 30 days during the peak winter season (December 2011) during which the animals were stall fed. Blood samples were collected at fortnightly interval. The growth, physiological response, blood biochemical response and endocrine response parameters were studied. The results reveal that cold stress had significant negative influence on all the parameters studied in the ewes. In conclusion, it can be said that cold stress had significant influence on the biological functions in the ewes that would result in the impairment of their production and reproductive efficiency as well. The study also indicates the relevance of provision of appropriate protective measures to foster cold during the extreme winter months in the arid and semi-arid tropical areas. 相似文献
60.
A study was conducted to assess the biological ability of Malpura rams to counter heat stress challenges and its impact on the productive performance in a semi-arid tropical environment. The eighteen adult Malpura rams (average body weight 55.0 kg) were divided into two groups, GI (n = 9; Control) and GII (n = 9; heat stress). The study was conducted for a period of 60 days. The results showed that body weight, body condition score, heart girth and feed intake were significantly (p < 0.05) lower in GII as compared to GI rams. The physiological responses i.e. respiration rate, pulse rate, rectal temperature and sweating rate (body and scrotum) were significantly (p < 0.05) higher in rams exposed to heat stress. Among the endocrine parameters, plasma T3, T4 and testosterone concentrations were significantly (p < 0.05) lower in GII rams, while cortisol concentration was significantly (p < 0.05) higher in GII rams. In addition, heat stress significantly (p < 0.05) reduced semen volume, total sperm motility, sperm concentration and progressive sperm motility in GII rams. The results indicated that Malpura rams adapted to the heat stress condition, however, while doing so their production performances were compromised. 相似文献