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1.
Seema Bhargava Sathnur Pushpakumar Naira Metreveli Srikanth Givvimani Suresh C. Tyagi 《Molecular biology reports》2014,41(8):4889-4898
Hyperhomocysteinemia (HHcy) is associated with cognitive decline and hearing loss due to vascular dysfunction. Although we have shown that HHcy-induced increased expression of matrix metalloproteinase-9 (MMP-9) is associated with cochlear pathology in cystathionine-β-synthase heterozygous (CBS+/?) mice, it is still unclear whether MMP-9 contributes to functional deficit in cognition and hearing. Therefore, we hypothesize that HHcy-induced MMP-9 activation causes vascular, cerebral and cochlear remodeling resulting in diminished cognition and hearing. Wildtype (WT), CBS+/?, MMP-9?/? and CBS+/?/MMP-9?/? double knock-out (DKO) mice were genotyped and used. Doppler flowmetry of internal carotid artery (ICA) was performed for peak systolic velocity [PSV], pulsatility index [PI] and resistive index [RI]. Cognitive functions were assessed by Novel Object Recognition Test (NORT) and for cochlear function Auditory brainstem response (ABR) was elicited. Peak systolic velocity, pulsatility and resistive indices of ICA were decreased in CBS+/? mice, indicating reduced perfusion. ABR threshold was increased and maximum ABR amplitude and NORT indices (recognition, discrimination) were decreased in CBS+/? mice compared to WT and MMP-9?/?. All these parameters were attenuated in DKO mice suggesting a significant role of MMP-9 in HHcy-induced vascular, neural and cochlear pathophysiology. Regression analysis of PSV with ABR and cognitive parameters revealed significant correlation (0.44–0.58). For the first time, MMP-9 has been correlated directly to functional deficits of brain and cochlea, and found to have a significant role. Our data suggests a dual pathology of HHcy occurring due to a decrease in blood supply (vasculo-neural and vasculo-cochlear) and direct tissue remodeling. 相似文献
2.
Expression of a beta thalassemia gene with abnormal splicing. 总被引:3,自引:1,他引:2
C Lapoumeroulie S Acuto F Rouabhi D Labie R Krishnamoorthy A Bank 《Nucleic acids research》1987,15(20):8195-8204
Expression of a cloned human beta thalassemia gene with a single base change at position 5 of IVS 1 has been analyzed 48 hours after transfer of the gene into HeLa cells (transient expression). Little or no normal beta globin mRNA accumulates in the presence of the abnormal beta gene in contrast to significantly more normal beta mRNA produced with other mutations at this same position. By contrast, large amounts of an abnormal beta globin mRNA are present; this is due to the use of a cryptic 5' splice site in exon 1 rather than the normal 5' splice site of IVS 1. The results indicate the variability of the effect on RNA splicing of different single base defects within IVS. 相似文献
3.
C. Lapouniéroulie O. Dunda R. Ducrocq G. Trabuchet M. Mony-Lobé J. M. Bodo P. Carnevale D. Labie J. Elion R. Krishnamoorthy 《Human genetics》1992,89(3):333-337
Summary The sickle cell mutation (s) arose as at least three independent events in Africa and once in Asia, being termed the Senegal, Benin, Bantu and Indian types respectively. An investigation in Cameroon was carried out to determine whether the atypical sickle genes observed in the neighboring countries are the result of recombination or the presence of a sickle cell mutation of a different genetic origin. It was conducted on 40 homozygous SS patients followed at the Blood Transfusion Center in the capital city of Yaoundé. On 80 s chromosomes, 13 exhibited a novel polymorphic pattern that was observed three times in the homozygous state. This chromosome contains an AT gene. The restriction fragment length polymorphism haplotype is different from all the other s chromosomes in both the 5 and 3 regions, but has previously been reported in sporadic cases. The (AT)8(T)5 sequence in the — 500 region of the gene is specific and different from that of the Senegal, Benin, Bantu or Indian s genes. All the carriers of this specific chromosome belong to the Eton ethnic group and originate from the Sanaga river valley. This observation strongly argues for yet another independent origin of the sickle cell mutation in Africa, here referred to as the Cameroon type. The Benin haplotype and a Benin/ Bantu recombinant haplotype have been observed in the other studied populations: Ewondo, Bamiléké, Bassa, Yambassa and Boulou. 相似文献
4.
Beta thalassemia due to a novel mutation in IVS 1 sequence donor site consensus sequence creating a restriction site 总被引:1,自引:0,他引:1
C Lapoumeroulie J Pagnier A Bank D Labie R Krishnamoorthy 《Biochemical and biophysical research communications》1986,139(2):709-713
During a systematic screening of Algerian thalassemics by determining the DNA polymorphism haplotypes in the beta globin gene cluster, a novel haplotype was identified. The DNA of a homozygous individual was cloned and sequenced. The mutation, a G----A change, at position 5 of the small intervening sequence, probably interferes with normal splicing events, and, moreover, creates a new Eco RV restriction site that provides a useful diagnostic tool for detecting this condition. 相似文献
5.
2 10-year marriage cohorts from 2 surveys of married women in Melbourne were compared on their timing of the 1st and 2nd births. The results showed that women who were married in the early 1970s were much more likely to delay their first birth until about the 3rd or 4th year of marriage compared with women who married in the 1960s. This tendency to delay the 1st birth was probably aided by effective contraception, as it coincided with widespread use of the oral contraceptive. There was no difference in the timing of the 2nd birth in relation th the 1st birth between the 2 marriage cohorts. Women who delayed childbearing also preferred smaller families. Indeed, the increase in the % of women delaying childbearing appears to be synonymous with the trend toward the two-child family. Altough the number of married women in the labor force increased significantly from the early to the later cohort, a desire to work was not usually cited as the reason for delaying childbearing. Rather, economic reasons were most frequently mentioned for delaying childbearing. 相似文献
6.
Non-ohmic proton conductance of mitochondria and liposomes 总被引:10,自引:0,他引:10
Direct measurements of the proton/hydroxyl ion flux across rat liver mitochondria and liposome membranes are reported. H+/OH- fluxes driven by membrane potential (delta psi) showed nonlinear dependence on delta psi both in mitochondria and in liposomes whereas delta pH-driven H+/OH- flux shows linear dependence on delta pH in liposomes. In the presence of low concentrations of a protonophore the H+/OH- flux was linearly dependent on delta psi and showed complex dependence on delta pH. The nonlinearity of H+/OH- permeability without protonophore is described by an integrated Nernst- Plank equation with trapezoidal energy barrier. Permeability coefficients depended on the driving force but were in the range 10(-3) cm/s for mitochondria and 10(-4)-10(-6) cm/s for liposomes. The nonlinear dependence of H+/OH- flux on delta psi explains the nonlinear dependence of electrochemical proton gradient on the rate of electron transport in energy coupling systems. 相似文献
7.
Planococcus citri (Risso) is one of the major pests of citrus orchards in India. For the control ofP. citri, an encyrtid parasite,Leptomastix dactylopii How. was introduced from West Indies in 1983. The parasite was mass bred and inoculative releases were made in 2 selected
citrus orchards where infestation of mealybug on fruits (sweet orange, seedless lime and acid lime) ranged from 38 to 65 per
cent. Establishment of the parasite in the 2 release orchards resulted in complete control of the mealybug within 3 to 4 months.
No insecticidal sprays were required subsequently for the control ofP. citri in the following seasons.
Contribution No. 152/85 of the IIHR, Bangalore — 560089. 相似文献
8.
Summary Gibberellins A3, A4+7 and A13 and (–)-kaurene delay floral-bud initiation and flowering and decrease the number of floral-buds and flowers in Impatiens balsamina under 4-hr photoperiods. They do not have any marked effect under 8-hr photoperiods. Under 16- and 24-hr photoperiods they hasten floral-bud initiation and flowering and increase the number of flowers, the effect being greater under 16- than under 24-hr days and the order of effectiveness being GA4+7>GA3>GA13>(–)-kaurene.While GA3 and GA4+7 promote extension growth, the effect being greater with the former, GA13 and (–)-kaurene do not promote it under any photoperiod. The magnitude of stem elongation in different treatments prior to floral-bud initiation increases from 4- to 8-hr photoperiods but decreases under 16- and 24-hr periods, the effect being more under 24-hr although both 16-and 24-hr photoperiods are noninductive for flowering. 相似文献
9.
Summary In the qualitative short-day plant Impatiens balsamina, gibberellic acid (GA3) not only promoted the formation of floral buds in response to suboptimal photoinductive conditions and reduced the number of SD cycles that are required for their development into flowers, but also caused initiation of floral buds under non-inductive photoperiods. In plants treated with repeated applications of GA3, the floral buds developed into flowers irrespective of whether the apex was left intact or was removed. In those that received a single application of GA3 the floral buds developed into flowers only in decapitated plants. 相似文献