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101.
Elucidating the underlying cause of unexplained syncope, palpitations or other possible arrhythmia-related symptoms is a formidable clinical challenge. Cardiac monitoring supplements the most important “test” in patients with syncope or palpitations, that of a thoughtful history and physical examination. Ideally, comprehensive physiologic monitoring during spontaneous symptoms would constitute what, at present, is an unattainable gold standard test for establishing a cause. Short of that goal, establishing an accurate symptom-rhythm correlation can often provide a diagnosis. Ambulatory outpatient monitoring is a powerful diagnostic tool for the evaluation of cardiac arrhythmias. Evolving technologies have provided a vast array of monitoring options for patients suspected of having cardiac arrhythmias, with each modality differing in duration of monitoring, quality of recording, convenience and invasiveness. Holter monitors, event monitors and external loop recorders are non-invasive and provide easily accessible short-term monitoring solutions. In instances where the diagnosis remains elusive, a more long-term strategy with an implantable loop recorder may be the preferred path.  相似文献   
102.
Radiotherapy may be effectively combined with plant derived radiosensitizers. Ferulic acid, a naturally occurring phenolic acid, has been reported to have free radical producing properties. In the present study, the radiosensitisation potential of ferulic acid has been tested in two cervical cancer cell lines (HeLa and ME-180) in vitro. Percentage of growth inhibition (MTT assay), colony survival, levels of lipid peroxidation (TBARS, CD and LHP), antioxidant status (SOD, CAT, GPx and GSH), oxidative DNA damage (% tail DNA, tail length, tail moment and Olive tail moment), apoptotic morphological changes (AO/EtBr staining) and intracellular ROS levels (DCFH-DA) were estimated. The present results show that ferulic acid (FA) enhances radiation effects by increasing lipid peroxidative markers in HeLa and ME-180 cells. We observed significant enhancement of ROS levels during ferulic acid plus radiation treatment. FA treatment alone increased intracellular ROS levels indicate its prooxidant nature. Similarly, we observed enhanced oxidative DNA damage and apoptotic morphological changes in FA plus radiation treated cells. The present data suggest radiation sensitizing property of FA in cervical cancer cells. Further investigations warrants to substantiate the present findings.  相似文献   
103.
Trachoma, the world's leading cause of preventable blindness, is produced by chronic ocular infection with Chlamydia trachomatis, an obligate intracellular bacterium. While many studies have focused on immune mechanisms for trachoma during chronic stages of infection, less research has targeted immune mechanisms in primary ocular infections, events that could impact chronic responses. The goal of this study was to investigate the function of neutrophils during primary chlamydial ocular infection by using the guinea pig model of Chlamydia caviae inclusion conjunctivitis. We hypothesized that neutrophils help modulate the adaptive response and promote host tissue damage. To test these hypotheses, guinea pigs with primary C. caviae ocular infections were depleted of neutrophils by using rabbit antineutrophil antiserum, and immune responses and immunopathology were evaluated during the first 7 days of infection. Results showed that neutrophil depletion dramatically decreased ocular pathology, both clinically and histologically. The adaptive response was also altered, with increased C. caviae-specific IgA titers in tears and serum and decreased numbers of CD4(+) and CD8(+) T cells in infected conjunctivae. Additionally, there were changes in conjunctival chemokines and cytokines, such as increased expression of IgA-promoting interleukin-5 and anti-inflammatory transforming growth factor β, along with decreased expression of T cell-recruiting CCL5 (RANTES). This study, the first to investigate the role of neutrophils in primary chlamydial ocular infection, indicates a previously unappreciated role for neutrophils in modulating the adaptive response and suggests a prominent role for neutrophils in chlamydia-associated ocular pathology.  相似文献   
104.

Background:

The major neurovascular involvement and large primary tumors are indication of amputation. The present study is an attempt to explore the feasibility of a limb salvage surgery in extremity sarcoma cases with major vessel involvement. Oncological outcomes and surgery-related morbidities are compared with those reported in literature.

Materials and Methods:

A retrospective review of all limb salvage surgeries done in our department between 2005 and 2008 was done and four cases of extremity sarcoma of lower limb involving femoral vessels analyzed. Interpretation of data from these cases, along with review of literature, is done.

Results:

In all these cases a wide monobloc excision was done adhering to oncological principles. This required resection of superficial femoral artery alone in two cases, resection of superficial femoral artery along with common femoral vein and femoral nerve in another, and of common femoral vein alone in yet another. Reconstruction was done in all these cases with reversed long saphenous vein graft. Histopathology of resected margins was free of tumor in all the four patients. One patient developed local recurrence and one developed distant metastsis. Two were disease free for one year with good functional limb, one has been disease-free for three years and another was disease-free at two years, after which he defaulted further follow-up. One patient developed arterial blowout which required ligation of common femoral artery which resulted in gangrene of the limb. He underwent amputation.

Conclusion:

Major neurovascular involvement in extremity sarcoma is not considered a contraindication for limb salvage surgery. Review of literature also supports our view. Post-operative wound related complications are more in this group of patients. However, long term functional outcome is good. Literature suggests a good long term local control after vascular resection and reconstruction.  相似文献   
105.

Background and aim

Tuberculous meningitis (TBM) is a debilitating form of CNS tuberculosis with a high morbidity and mortality in spite of treatment. The diagnosis is based on clinical, radiological and laboratory features. The classical CT features of basal exudates, hydrocephalus, infarcts and granulomas have been mostly reported in younger individuals. Our aim was to study imaging features of TB meningitis in adults over the age of 50 years.

Materials and methods

Clinical, imaging and laboratory features of 53 adult patients over the age of 50 years (sixth to eighth decades) were studied retrospectively. Diagnosis of TBM was based on clinical and laboratory features.

Results

Imaging features were the conspicuous absence of typical features of TBM (ie, basal meningeal enhancement, hydrocephalus, infarcts/granulomas were seen in only a minority of patients).

Conclusions

CT features of TBM in elderly patients were few, atypical and non‐contributory for diagnosis, probably because of age related immune senescence. Strong clinical suspicion and correlation with laboratory findings is necessary for early diagnosis.The elderly population is increasing all over the world, including India, because of increased life expectancy. The incidence of tuberculosis has been estimated to be higher in elderly subjects than in younger populations.1 Non‐specific clinical symptoms may be masked by illnesses prevalent in old age, such as diabetes mellitus, vascular diseases and malignancies. CT has been used in the evaluation of tuberculous meningitis (TBM) to identify complications and for prognosis. CT features include basal meningeal enhancement, hydrocephalus, infarctions and focal granulomas.2 We report a retrospective study of clinical and radiological features of TBM in patients over the age of 50 years (sixth to eighth decades).  相似文献   
106.
Sesamol (SM) is a dietary phytochemical present in the processed sesame oil. In this present study we have evaluated the antioxidant potential of SM and its role in the protection of radiation-induced DNA damage in γ-irradiated mice. The antioxidant properties of SM were evaluated by using different in vitro antioxidant assays. SM shows scavenging effect against hydroxyl (OH), superoxide anion (O2), nitric oxide, 2,2-azino-bis-3-ethylbenzothiazoline-6-sulphonic acid radical cation (ABTS+) and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals. Our results demonstrate that SM exhibits strong antioxidant property in all the in vitro assays. When mice were exposed to 7 Gy γ-radiations there was an increase in % tail DNA, tail length, tail moment and Olive tail moment in blood lymphocytes. SM (100 mg/kg b.wt) pretreatment significantly decreased the % tail DNA, tail length, tail moment and Olive tail moment in irradiated mice lymphocytes. These results suggest that SM protects γ-radiation-induced DNA damage in mice lymphocytes, which may be attributed to its antioxidant property.  相似文献   
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Depletion of estrogens occurs in women during menopause, while in experimental animals, oophorectomy is a common method to deplete the animals of their gonadal hormones. Recently, phytoestrogens derived from plants have been tried as estrogen substitutes during menopause. In the present study an isoflavones methanol extract from red clover Trifolium pratense (Linn.) was administered orally (500 mg/kg of body weight) to ovariectomized (OVX) and normal (controls) rats for 90 and 180 days. Their pain threshold was monitored using tail flicking and formalin test methods. Observations showed that the OVX rat pain threshold was reduced due to estrogen deprivation, whereas the pain threshold levels in OVX rats treated with isoflavones extract was similar to the control animals. The present study demonstrated the influence of phytoestrogen on long‐term OVX rats in pain perception in the absence of ovarian estrogen and without toxic side effects. However, the actions of gonadal hormones on nociceptive axis are myriad and complex, so further studies on the exact physiological mechanism of the phytoestrogen action on nociceptive axis is warranted. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
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