Following a large myocardial infarction (MI), remaining viable muscle often undergoes pathological remodelling and progresses towards chronic heart failure. Mitochondria may also be affected by this ...process and, due to their functional importance, likely contribute to the progression of the disease. Aerobic interval training (AIT) has been shown effective in diminishing pathological myocardial transformation, but the effects of AIT on mitochondrial function in hearts undergoing remodelling are not known.
Adult female Sprague-Dawley rats were randomized to either 8 weeks of aerobic interval treadmill running (5 days/week), which started 4 weeks after left coronary artery ligation (MI-Trained), or a sedentary group (MI-Sedentary). Echocardiography was performed before and after the 8-week period, at which point the left ventricles (LVs) were also harvested. Twelve weeks after surgery, MI-Sedentary rats had significantly lower LV fractional shortening compared with MI-Trained rats. Complex I-dependent respiration assessed in isolated LV mitochondria was decreased by ∼37% in MI-Sedentary and 17% in MI-Trained animals (group differences P < 0.05), compared with sham-operated animals. This was paralleled with diminished ATP production and increased degree of protein oxidation in MI-Sedentary rats. The enzymatic activity of complex I was also decreased to a greater extent in MI-Sedentary than in MI-Trained animals, with no evidence of its reduced expression. When complex II substrate was used, no differences among the three groups were observed.
Exercise reduces LV contractile deterioration in post-infarction heart failure and alleviates the extent of mitochondrial dysfunction, which is paralleled with preserved complex I activity.
Limited information exists concerning arterial blood pressure (BP) changes in underwater breath-hold diving. Simulated chamber dives to 50 m of freshwater (mfw) reported very high levels of invasive ...BP in two divers during static apnea (SA), whereas a recent study using a noninvasive subaquatic sphygmomanometer reported unchanged or mildly increased values at 10 m SA dive. In this study we investigated underwater BP changes during not only SA but, for the first time, dynamic apnea (DA) and shortened (SHT) DA in 16 trained breath-hold divers. Measurements included BP (subaquatic sphygmomanometer), ECG, and pulse oxymetry (arterial oxygen saturation, SpO₂, and heart rate). BP was measured during dry conditions, at surface fully immersed (SA), and at 2 mfw (DA and SHT DA), whereas ECG and pulse oxymetry were measured continuously. We have found significantly higher mean arterial pressure (MAP) values in SA (∼40%) vs. SHT DA (∼30%). Postapneic recovery of BP was slightly slower after SHT DA. Significantly higher BP gain (mmHg/duration of apnea in s) was found in SHT DA vs. SA. Furthermore, DA attempts resulted in faster desaturation vs. SA. In conclusion, we have found moderate increases in BP during SA, DA, and SHT DA. These cardiovascular changes during immersed SA and DA are in agreement with those reported for dry SA and DA.
Coastal region of Croatia is rich in autochthonous grape varieties. Many of them have been almost abandoned, such as the autochthonous varieties of Kastav (Croatia), used for the production of the ...Kastavska Belica wine. Therefore, the rationale of the presented study is to characterize autochthonous grape varieties Verdić, Mejsko belo, Jarbola, Divjaka and Brajkovac. In addition, we performed a molecular characterization of the corresponding Belica wines.
Firstly, the genetic origin and ampelographic and economic characteristics of five autochthonous grape varieties were determined. Standard physicochemical profiles and phenolic components of 12 wines from different producers were determined by liquid chromatography coupled to triple quadrupole mass spectrometer (LC-QQQ-MS). Fourier-transform infrared spectroscopy (FTIR) was used for determination of standard physicochemical parameters.
Ampelographic analysis, which includes the data on producing characteristics and cluster and berry composition of the varieties, revealed significant differences between the analysed grape varieties. Results of the physicochemical analysis of the Belica wine showed that all wines met the requirements needed for the production of quality and top quality wines labelled with protected designation of origin (PDO) in Croatian coastal region. The LC-QQQ-MS analysis confirmed the presence of different phenolic components in the Belica wines, where the most prominent phenols were flavonoids from the flavan-3-ol group. Overall, these results showed that autochthonous grapes from the Kastav region can be used for production of wines with added market value due to a growing demand for autochthonous products on the global market.
The presented results give scientific insight and a basis for further determination of the optimal cultivation technology aimed to take advantage of the best characteristics of each variety for production of a wine with desirable features.
The current guidelines for the management of adrenal incidentaloma advise hormonal and radiological follow-up of patients for 2-5 years after the initial diagnosis. However, the vast majority of ...adrenal incidentaloma are non-functional benign cortical adenomas that require no treatment, so the routine application of the current strategies often results in a number of unnecessary biochemical and radiological investigations. The aim of this study was to analyse the clinical course of patients with adrenal incidentaloma and to provide a critical review of the current management strategy of the disease.
This was a retrospective study performed in the Croatian Referral Center for adrenal gland disorders. The study included 319 consecutive patients with adrenal incidentaloma, 174 of which were followed for at least 24 months.
The vast majority of patients were diagnosed with benign adrenal masses, whereas in about 5% of them adrenal tumor corresponded to adrenal carcinoma or metastasis. Tumor density was found to be superior to tumor size in distinguishing benign adrenal masses from malignant tumors and pheochromocytomas. During the follow-up, no patient demonstrated a clinically significant increase in tumor size. In addition, no changes, either in metanephrines and normetanephrines or in the activity of renin-aldosterone axis, were observed during the follow-up. Six patients developed subclinical Cushing's syndrome (SCS) whereas eight patients with SCS showed biochemical remission during follow-up.
The study suggests that the risk of an adrenal mass initially diagnosed as benign and non-functional becoming malignant or hormonally active is extremely low. Therefore, the clinical management of those patients should be tailored on an individual basis in order to avoid unnecessary procedures.
Exercise training reduces pathological remodeling and improves cardiac function in ischemic heart failure; however, causal mechanisms underlying the cardiac benefits of exercise are poorly ...understood. Because opening of adenosine triphosphate (ATP)-sensitive K ⁺(KATP) channels protects the heart during myocardial stress, we hypothesized that such a mechanism is responsible for some of the cardiac benefits induced by exercise in postinfarction chronic heart failure (CHF).
Left ventricular myocytes were isolated from three groups of rats: Sham, CHF Tr (4 wk after myocardial infarction, rats underwent 8 wk of aerobic interval training 5 d·wk⁻¹) and CHF Sed (rats sedentary for 12 wk after infarction). Cardiomyocyte survival after oxidative stress exposure (200 μM H2O2) and calcium handling (cells loaded with Fura-2 AM and electrically paced at 1 Hz) were assessed in the presence of KATP channel inhibitor glibenclamide. Expression of KATP subunits (SUR2A and Kir6.2) was evaluated using immunoblotting.
Exercise improved cardiac function in CHF Tr animals. Cardiomyocytes from CHF Sed rats were more susceptible to oxidative stress-induced cell death than CHF Tr and Sham cardiomyocytes, with glibenclamide completely abolishing the protective effect of exercise. Glibenclamide did not affect cardiomyocyte survival in Sham or CHF Sed rats. In addition, exercise increased the systolic Ca²⁺ transient amplitude and improved diastolic Ca²⁺ removal in CHF Tr cardiomyocytes (compared with CHF Sed); both were significantly attenuated by glibenclamide. Exercise resulted in increased expression of KATP channel subunits in CHF Tr hearts, with more pronounced and significant effect on SUR2A.
Our data suggest that KATP channel upregulation induced by chronic exercise likely mediates some of exercise-induced beneficial effects on cardiac function in postischemic heart failure.
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