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61.
P.‐L. Kuo J. A. Schrack M. D. Shardell M. Levine A. Z. Moore Y. An P. Elango A. Karikkineth T. Tanaka R. de Cabo L. M. Zukley M. AlGhatrif C. W. Chia E. M. Simonsick J. M. Egan S. M. Resnick L. Ferrucci 《Journal of internal medicine》2020,287(4):373-394
Over the past three decades, considerable effort has been dedicated to quantifying the pace of ageing yet identifying the most essential metrics of ageing remains challenging due to lack of comprehensive measurements and heterogeneity of the ageing processes. Most of the previously proposed metrics of ageing have been emerged from cross‐sectional associations with chronological age and predictive accuracy of mortality, thus lacking a conceptual model of functional or phenotypic domains. Further, such models may be biased by selective attrition and are unable to address underlying biological constructs contributing to functional markers of age‐related decline. Using longitudinal data from the Baltimore Longitudinal Study of Aging (BLSA), we propose a conceptual framework to identify metrics of ageing that may capture the hierarchical and temporal relationships between functional ageing, phenotypic ageing and biological ageing based on four hypothesized domains: body composition, energy regulation, homeostatic mechanisms and neurodegeneration/neuroplasticity. We explored the longitudinal trajectories of key variables within these phenotypes using linear mixed‐effects models and more than 10 years of data. Understanding the longitudinal trajectories across these domains in the BLSA provides a reference for researchers, informs future refinement of the phenotypic ageing framework and establishes a solid foundation for future models of biological ageing. 相似文献
62.
Sampath Marimuthu Abdul Abdul Rahuman Chidambaram Jayaseelan Arivarasan Vishnu Kirthi Thirunavukkarasu Santhoshkumar Kanayairam Velayutham Asokan Bagavan Chinnaperumal Kamaraj Gandhi Elango Moorthy Iyappan Chinnadurai Siva Loganathan Karthik Kokati Venkata Bhaskara Rao 《Asian Pacific journal of tropical medicine》2013,6(9):682-688
ObjectiveTo assess the acaricidal activity of titanium dioxide nanoparticles (TiO2 NPs) synthesized from flower aqueous extract of Calotropis gigantea(C. gigantea) against the larvae of Rhipicephalus (Boophilus) microplus [R. (B.) microplus] and the adult of Haemaphysalis bispinosa (H. bispinosa).MethodsThe lyophilized C. gigantea flower aqueous extract of 50 mg was added with 100 mL of TiO(OH)2 (10 mM) and magnetically stirred for 6 h. Synthesized TiO2 NPs were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Scanning electron microscopy (SEM), and Energy dispersive X-ray spectroscopy (EDX). The synthesised TiO2 NPs were tested against the larvae of R. (B.) microplus and adult of H. bispinosa were exposed to filter paper impregnated method.ResultsXRD confirmed the crystalline nature of the nanoparticles with the mean size of 10.52 nm. The functional groups for synthesized TiO2 NPs were 1 405.19, and 1 053.45 cm?1 for -NH2 bending, primary amines and amides and 1 053.84 and 1 078.45 cm?1 for C-O. SEM micrographs of the synthesized TiO2 NPs showed the aggregated and spherical in shape. The maximum efficacy was observed in the aqueous flower extract of C. gigantea and synthesized TiO2 NPs against R. (B.) microplus (LC50=24.63 and 5.43 mg/L and r2=0.960 and 0.988) and against H. bispinosa (LC50= 35.22 and 9.15 mg/L and r2 = 0.969 and 0.969), respectively.ConclusionsThe synthesized TiO2 NPs were highly stable and had significant acaricidal activity against the larvae of R. (B.) microplus and adult of H. bispinosa. This study provides the first report of synthesized TiO2 NPs and possessed excellent anti-parasitic activity. 相似文献
63.
Effect of Foeniculum vulgare Mill. seed extract on the genital organs of male and female rats 总被引:3,自引:0,他引:3
T Malini G Vanithakumari N Megala S Anusya K Devi V Elango 《Indian journal of physiology and pharmacology》1985,29(1):21-26
Following the oral administration of acetone extract of Foeniculum vulgare (fennel) seeds for 15 days is male rats, total protein concentration was found to be significantly decreased in testes and vas deferens and increased in seminal vesicles and prostate gland. There was a decrease in activities of acid and alkaline phosphatase in all these regions, except that alkaline phosphatase was unchanged in vasa. In female rats, oral administration of the extract for 10 days led to vaginal cornification and oestrus cycle. While moderate doses caused increase in weight of mammary glands, higher doses increased the weight of oviduct, endometrium, myometrium, cervix and vagina also. The results confirm the oestrogenic activity of the seed extract. 相似文献
64.
Elango N Samuel S Chinnakkannu P 《Clinica chimica acta; international journal of clinical chemistry》2006,373(1-2):92-98
BACKGROUND: Oxidative stress is implicated in oral carcinogenesis and has been found to be aggravated during radiotherapy. A great deal of attention has been focused on the possible therapeutic implications of selenium as a potent antioxidant. We determined whether selenium supplementation to radiation treated oral cancer patients render improvement in the antioxidant status against oxidative stress. METHOD: Blood samples were collected from stage (III) oral cancer patients before initiating radiotherapy (Group B) (n=63) and this group is bifurcated into Group C-patients given radiotherapy alone (n=27) and Group D-patients given radiotherapy and supplemented with selenium (400 mug/day for 6 months) (n=36). Both Group C and D were followed up for 6 months. We evaluated the plasma selenium concentration, non-enzymatic system including GSH, vitamins E, C, A and ceruloplasmin and enzymatic antioxidant system including superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, glucose-6-phosphate dehydrogenase. RESULTS: The concentrations of selenium, all non-enzymatic antioxidants and the activities of enzymatic antioxidants were found to be lowered in oral cancer patients (Group B), compared to normal (Group A) (p<0.05). Similar decrease in the concentration of selenium and antioxidants status was observed in radiotherapy group (Group C) (p<0.05). On the contrary, selenium group (Group D) showed marked increase in the concentrations of selenium and antioxidant status at 6 months compared to radiation group (Group C) (p<0.05). CONCLUSION: The observed result represents the antioxidant property of selenium through the improvement of antioxidant defense system. Selenium supplementation could be of great interest in protecting cells against oxidative stress. 相似文献
65.
66.
Sigmoid volvulus an update 总被引:1,自引:0,他引:1
Lal SK Morgenstern R Vinjirayer EP Matin A 《Gastrointestinal endoscopy clinics of North America》2006,16(1):175-187
Sigmoid volvulus is the third most common cause of colonic obstruction in the United States after cancer and diverticulitis. Etiologic factors include anatomic variation, chronic constipation, neurologic disease, and megacolon. Management of sigmoid volvulus involves relief of obstruction and the prevention of recurrent attacks; the outcome depends on the population and selection of patients. Although volvulus is uncommon, it may be encountered during pregnancy and is a condition that poses significant risk to both mother and fetus requiring a management strategy that varies with each trimester. 相似文献
67.
Ramamurty N Raja D Gunasekaran P Varalakshmi E Mohana S Jin L 《Journal of medical virology》2006,78(4):508-513
The aims of the present study were to confirm measles outbreaks by detection of measles-specific IgM antibodies, isolation of measles virus, and genetic characterization to document the circulating genotypes in Tamil Nadu. Eight outbreaks were reported from six districts of Tamil Nadu, India during the period Jan-Dec 2003. Blood samples were collected for serology, urine, and throat swabs for virus isolation. Genotypic characterization of measles isolates was based on the sequence of the N gene. All the clinically suspected outbreaks (n = 8) were confirmed by serology; six out of the eight as measles and two as combination of measles and rubella highlighting the need to carry out rubella serology on measles-negative samples. Genetic characterization of three isolates obtained revealed one as genotype D4 and two as D8. Measles genotypes D4 and D8 were found to circulate in three districts of Tamil Nadu. It is necessary to be aware of the circulating genotypes within the geographical area. The information would be valuable to evaluate control measures and identify viral transmission and importation. 相似文献
68.
69.
Vivekanandan Dhukaram FRCS Michael G. Hullin FRCS Chinnasamy Senthil Kumar FRCS 《The Journal of foot and ankle surgery》2006,45(6):400-409
A retrospective analysis was performed to describe the effects of Mitchell and Scarf osteotomies on plantar pressure distribution and their relevance to the clinical outcome. This study evaluated 28 patients who underwent operations for moderate to severe hallux valgus deformities over a period of 3 years at 2 different centers. Twenty-two Mitchell and 22 Scarf osteotomies were performed on 28 patients with a mean follow-up of 23 months (13-62 months). The average postoperative American Orthopaedic Foot and Ankle Society scores after Mitchell and Scarf osteotomies were 74 and 84, respectively. A control group of 15 individuals with 20 healthy feet were included for comparison. The plantar pressures were documented with the Musgrave footplate. The pressure distributions under the first metatarsal head were within normal limits in both study groups compared with the control group (P = .77). After Mitchell osteotomies, deficient load bearing was noted under the hallux (P = .007), coupled with overloading of the second and third metatarsal heads (P = .01). But after the Scarf procedures, increased weight bearing was noted at the heel (P = .04) and midfoot (P = .09), with better load distribution under the hallux. However, it was not comparable with the control group. Correlation of American Orthopaedic Foot and Ankle Society scores and pressure variables demonstrated a significant positive correlation with hallux loading (P = .001). This study demonstrates that adequate hallux loading is imperative for a better outcome of the procedure. Mitchell and Scarf osteotomies do not restore the load-bearing function of the foot to normal, whereas hallux loading plays an important role for a better outcome of the procedure. 相似文献
70.
Posterior fossa dural arteriovenous fistulae (DAVF) are uncommon lesions. In the past, treatment of these lesions has involved both surgical and endovascular techniques, the latter being favoured in contemporary neurovascular medicine. We describe our experience in the case of a 71-year-old woman with a posterior fossa DAVF who presented with sudden onset headache, collapse and neurological deficit secondary to a subarachnoid haemorrhage. She was treated by means of direct surgical access of the lesion combined with endovascular occlusion resulting in a radiological and clinical cure. 相似文献