Abstract Background Obstructive sleep apnea (OSA) importantly contributes to the occurrence of atrial fibrillation (AF) in humans, but the mechanisms are poorly understood. Experimental research has ...provided insights into AF promotion by acute OSA episodes. However, patients with OSA usually have frequent nocturnal episodes for some time before manifesting AF. Objectives The goal of this study was to test the hypothesis that repetitive OSA causes cardiac remodeling that predisposes to AF. Methods We mimicked OSA by using a mechanical ventilator and closing the airway at end-expiration with a 3-way stopcock (OSA rats). Matched control groups included rats with the ventilator stopped but airway left open (open airway rats) and continuously ventilated rats (sham rats). OSA rats were exposed to 20 consecutive 2-min cycles of 40 s of apnea/80 s of ventilation per day, 5 days per week for 4 weeks. Results OSA significantly increased the duration of AF from (median interquartile range) 2.6 s 1.9 s to 8.9 s (shams) and 16 s 1.8 s to 93 s (open airway) to 49s 34 s to 444 s. AF inducibility increased to 56% (9 of 16) of OSA rats; this is up from 15% (2 of 13) and 13% (2 of 15) in open airway and sham rats, respectively (p < 0.05). OSA rats exhibited substantial atrial conduction slowing on optical mapping, along with connexin-43 down-regulation on both quantitative immunofluorescence (expression reduced by 58% vs sham rats) and Western blot (reduced by 38%), as well as increased atrial fibrous tissue content (by 71%). OSA also caused left ventricular hypertrophy, dilation, and diastolic dysfunction and enhanced AF inducibility during superimposed acute OSA episodes to 82.4% of rats. Conclusions Chronically repeated OSA episodes cause AF-promoting cardiac remodeling, with conduction abnormalities related to connexin dysregulation and fibrosis playing a prominent role. This novel animal model provides mechanistic insights into an important clinical problem and may be useful for further exploration of underlying mechanisms and therapeutic approaches.
Avaliação ultra-sonográfica e pelo Doppler colorido do carcinoma de células transicionais da bexiga em cães Froes, T.R.(UFPR Departamento de Medicina Veterinária); Iwasaki, M.(USP Faculdade de Medicina Veterinária e Zootecnia); Campos, A.G.(USP FMVZ Hospital Veterinário) ...
Arquivo Brasileiro de Medicina Veterinária e Zootecnia/Arquivo brasileiro de medicina veterinária e zootecnia,
12/2007, Volume:
59, Issue:
6
Journal Article
Peer reviewed
Open access
Estudaram-se os aspectos ultra-sonográficos das lesões sugestivas de carcinoma de células transicionais (CCT), investigou-se a contribuição do mapeamento Doppler colorido e de amplitude no ...diagnóstico das lesões sugestivas de CCT e verificou-se a acurácia do método de biópsia ecodirigida por sucção traumática via sondagem uretral na coleta de material para confirmação diagnóstica CCT da bexiga. Para tal, foram selecionados nove cães que atendiam aos critérios de inclusão determinados. Destes, sete apresentavam CCT. A ultra-sonografia permitiu a detecção de massas exofílicas com características vegetantes em cinco cães, e de lesões infiltrativas na parede vesical estendendo-se para a uretra em dois. Pelo exame com Doppler colorido e de amplitude, constatou-se a vascularização interna da massa, indicativa de neoangiogênese tumoral, em quatro animais. A técnica de sucção traumática por aspiração permitiu a elucidação diagnóstica em cinco dos sete animais com CCT. Concluiu-se que, na maioria dos casos, a ultra-sonografia propicia a identificação de lesões sugestivas de CCT, constituindo a primeira técnica de diagnóstico por imagem indicada para pacientes que apresentem hematúria e disúria.
The aims of this study were to evaluate the ultrasonographic findings in dogs with suggestive transitional cell carcinoma (TCC) lesion, to investigate the use of the color Doppler for the diagnosis of that condition and to establish the efficacy of the ultrasound catheter biopsy by suction via urethral probing for collecting material to confirm bladder TCC. A total of nine dogs were selected, seven with TCC confirmed. The ultrasonographic finding in TCC patients detected sessile masses in the bladder of five dogs and infiltrative mural lesion extent to the urethra in two dogs. The color Doppler and the power Doppler showed the internal vascular flow in four animals indicating tumor neoangiogenesis. It was concluded that the ultrasonography may identify abnormalities in the majority of cases with suggestive lesions of TCC and the ultrasonographic evaluation should be considered as the first diagnostic imaging modality in patients presented with hematuria and dysuria.
Abstract Aim This study looked at whether a history of diabetes mellitus (DM) is associated with a higher risk of externally caused death (by suicide and accident), using data for a large ...population-based prospective cohort from an Asian population. Methods Data collected between 1990 and 2012 from the Japan Public Health Centre-based Prospective Study were analyzed, and Poisson regression models were used to calculate adjusted risk ratios (RR) for external causes of death. Results The population-based cohort comprised 105,408 Japanese residents (49,484 men and 55,924 women; mean age: 51.2 SD 7.9 years). At baseline, 3250 (6.6%) men and 1648 (3.0%) women had a history of DM. During the follow-up period, 113 external deaths (41 suicides and 72 accidents) were noted among those with a history of DM, with 1304 external deaths (577 suicides and 727 accidents) among those without such a history. A higher risk of external death (men, RR: 1.4, 95% CI: 1.2–1.8; women, RR: 1.6, 95% CI: 1.01–2.4) was observed in those with a history of DM. Also, among those aged 40–49 years (RR: 1.9, 95% CI: 1.3–2.7) and 50–59 years (RR: 1.4, 95% CI: 1.05–1.9) at baseline, the risk of external death was significantly higher in those with a history of DM. Conclusion Compared with people with no history of DM, those with such a history had a significantly greater risk of externally caused death (particularly accidental deaths) in both genders and in those aged ≤ 59 years at baseline.
An orthotropic steel deck is quite susceptible to fatigue cracking at its welded joints depending on the structural stiffness, occurrence of high-magnitude cyclic load stress, and complicated ...geometric details of the welded joints. This study experimentally and numerically investigated the structural behavior of an orthotropic steel deck with bulb ribs. The behavior of the deck was examined, particularly the warped deformations of the developed fatigue cracks and the uniform stress distributions against moving loads attributed to the deck's asymmetric bulb ribs. An artificial fatigue crack serving as an authentic model of a fatigue crack was developed in the longitudinal bulb rib of an orthotropic steel deck in actual service. The loading tests were conducted on an orthotropic steel deck with artificial fatigue cracks. The test results were evaluated based on the artificial fatigue crack length on the longitudinal bulb ribs and compared with a nonlinear full finite-element analysis model considering the nonlinear contact behavior of artificial fatigue cracks.
Experiments with low-energy kaons at the DAΦNE Collider Sirghi, D
13th International Conference on Beauty, Charm and Hyperon Hadrons, BEACH 2018,Peniche, Portugal,2018-06-17 - 2018-06-23,
01/2019, Volume:
1137, Issue:
1
Journal Article, Conference Proceeding
Peer reviewed
Open access
The investigations of light kaonic atoms offer the unique opportunity to perform experiments equivalent to scattering at vanishing relative energies, being their atomic binding energies in the keV ...range. This allows the determination of the hadron-nucleus interaction at threshold without the need of an extrapolation to zero relative energy. The energy shift and broadening of the lowest-lying states of such atoms, induced by the kaon-nucleus strong interaction, can be determined with high precision from atomic X-ray spectroscopy. The lightest atomic systems, kaonic hydrogen and kaonic deuterium, deliver the isospin-dependent kaon-nucleon scattering lengths. The most precise kaonic hydrogen measurement to date, together with an exploratory measurement of kaonic deuterium, were carried out by the SIDDHARTA collaboration at the DAΦNE electron-positron collider of LNF-INFN. The measurement of kaonic deuterium will be realized in the near future by SIDDHARTA-2, a major upgrade of SIDDHARTA. A correlated study of the kaon-nuclei interaction at momenta below 130 MeV/c is carried out by the AMADEUS collaboration, using the KLOE detector and dedicated targets inserted near the collider interaction point. In this paper an overview of the main results obtained by SIDDHARTA together with the future plans, the SIDDHARTA-2 experiment and with the preliminary results of the study of charged antikaons interacting with nuclei by the AMADEUS collaboration, are shown.
To our knowledge, no prospective study has examined the association between blood levels of organochlorines and breast cancer risk in Asian countries. Here, we tested the hypothesis that higher blood ...levels of organochlorines are associated with an increased risk of breast cancer in Japanese women. A total of 24,226 women subjects of the Japan Public Health Center-based Prospective Study aged 40 to 69 years who responded to the baseline questionnaire and provided blood in 1990–1995 were followed to December 2002. During 10.7 years follow-up, 144 cases of breast cancer were newly diagnosed. Two matched-controls for each case were selected from the cohort. Plasma levels of
p,
p'-dichlorodiphenyltrichloroethane (
p,
p'-DDT),
p,
p'-dichlorodiphenyldichloroethylene (
p,
p'-DDE), hexachlorobenzene (HCB), and β-hexachlorocyclohexane (β-HCH) were measured. A conditional logistic regression was used to estimate the odds ratio (OR) of breast cancer according to cholesterol-adjusted organochlorine levels based on 139 matched pairs. We found no statistically significant positive association between plasma organochlorine level and breast cancer risk. Adjusted ORs for
p,
p'-DDT, HCB, and β-HCH were less than 1. For
p,
p'-DDE, adjusted OR for the highest versus lowest quartile was 1.48 (95% confidence interval 0.70-3.13; p for trend
=
0.25). A stratified analysis by menopausal status showed positive associations for
p,
p'-DDT and
p,
p'-DDE in premenopausal but not postmenopausal women, although without statistical significance. Our data do not support the hypothesis that plasma levels of
p,
p'-DDT,
p,
p'-DDE, HCB, and β-HCH are associated with an overall increased risk of breast cancer among Japanese women.
Abstract The neuroprotective potential and therapeutic time window for fasudil, a Rho-kinase inhibitor (RKI), were evaluated for delayed neuronal death in gerbils. A preliminary screening was done on ...fasudil, ozagrel, and edaravone using a single administration in a delayed neuronal death study. Intraperitoneal (i.p.) administration of edaravone, a free radical scavenger (3, 10 mg/kg) immediately after re-circulation did not reduce neuronal degeneration. We previously reported that ozagrel, a thromboxane A2 synthetase inhibitor (30 mg/kg) also did not reduce neuronal degeneration, while fasudil (3, 30 mg/kg) significantly protected against the ischemia-induced neuronal loss. To clarify the therapeutic time window of fasudil, which showed a positive effect in a preliminary screening, animals received their first i.p. administration of fasudil (10 mg/kg) 24 or 48 h after ischemia. Administration of fasudil twice daily was continued until day 6. Fasudil significantly protected against the ischemia-induced delayed neuronal death when the treatment was started 24 h after ischemia. In gerbils, hydroxyfasudil, an active metabolite of fasudil, was found following an i.p. administration of fasudil (10 mg/kg), and the value of the area under the plasma level curve of hydroxyfasudil was 7 times higher than that of fasudil. Hydroxyfasudil may contribute to the potency of fasudil. The present findings indicate that the RKI fasudil reduces ischemic neuronal damage with a wide therapeutic time window in gerbil, and may be useful in the treatment of acute ischemic stroke in humans.
Few studies have explored the significance of carotid endarterectomy (CEA) in long-term prognosis in Japanese patients. In the present study, we precisely elucidated the demographic and radiologic ...data, surgical morbidity and mortality, and long-term outcome in 135 Japanese patients who underwent a total of 142 CEAs due to 70%-99% stenosis of the internal carotid artery at our hospitals over a 10-year period. The prevalence of risk factors was similar to those found in previous studies in Western countries. Surgical mortality (0.7%) and morbidity (2.8%) were relatively low. Blood flow studies done immediately after CEA revealed postoperative hyperperfusion in 8 patients (5.6%), but none of these patients exhibited related symptoms. Over the mean follow-up period of 38.7 months, a total of 9 patients died (6.7%), due mainly to malignancies. Cerebrovascular events occurred in 12 patients (8.5%), including ipsilateral ischemic stroke in 2 (1.4%). In addition, 11 patients (8.2%) developed vascular disorders in other organs, including coronary artery disease and chronic renal failure. Follow-up radiologic examination revealed restenosis of >50% in 3 carotid arteries (2.1%). Stenosis of the contralateral carotid arteries progressed to >70% in 12 patients (9.2%). This study strongly suggests that microsurgical CEA is feasible and effective in preventing subsequent ipsilateral ischemic stroke in Japanese patients; however, long-term medical and radiologic surveillance is essential to reduce the incidence of ischemic stroke in other areas and of vascular disorders in other organs to improve prognosis.
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