Distribution of excitation energy in photosynthesis: a study of heat loss, photo chemical activity and fluorescence emission in intact calls of cyanobacterium.

Photosynthetic state transitions were investigated in the cyanobacterium Synechococcus sp. PCC 6301 by studying fluorescence emission, heat loss, and PS I activity in intact cells brought to state 1 and state 2. 77K fluorescence emission spectra were modelled with a sum of 6 components corresponding to PBS, PS II, and PS I emissions. The modelled data showed a large decrease in PS II fluorescence accompanied with a small increase in the PS I fluorescence upon transition to state 2 for excitation wavelengths absorbed by both PBS and ChI ll.. The fluorescence changes seen with ChI .a. excitations do not support the predictions of the mobile PBS model of state transition in PBS-containing organisms. Measurements of heat loss from intact cells in the two states were similar for both ChI it. and PBS excitations over three orders of magnitude of laser flash intensity. This suggests that the PBS does not become decoupled from PS II in state 2 as proposed by the PBS detachment model of state transition in PBS-containing organisms. PS I activity measurements done on intact cells showed no difference in the two states, in contrast with the predictions of all of the existing models of state transitions. Based on these results a model for state transition In PBScontaining organisms is proposed, with a PS II photoprotectory function

Ventricular Tachycardia in Pregnant Patients

Ventricular tachycardia although not common, can occasionally complicate pregnancy. Its presence may indicate an underlying cardiac structural abnormality, or undiagnosed congenital arrhythmic disease. However, some pregnant patients with ventricular tachycardia have structurally normal hearts. Two cases of ventricular tachycardia in pregnant patients with structurally normal hearts are presented and an approach to diagnosis and management of such patients are discussed

Acute Coronary Syndrome in Pregnancy

Acute coronary syndrome (ACS) in pregnancy has traditionally been considered to be a rare event, but the combination of normal physiological changes of pregnancy and more prevalent cardiovascular risk factors are increasing its incidence in this population. The present report describes a 39 year-old woman that is seven weeks pregnant presenting with a non ST elevation myocardial infarction. The incidence, risk factors, pathophysiology and management of ACS in pregnancy are discussed

The effect of combination of Tamoxifen with interval and continue training on tumor mass in Mice with breast cancer tumor

Background: Beast cancer is considered as the most common malignancy among females in the world .in Iran, this cancer is also the most prevalent malignancy among women. The aim of this study is to compare the effects of Tamoxifen and interval and continues training on tumor mass Balb/c mice suffering from breast cancer Methods: for this reason 30 female balb/c mice were utilized and after transplant carcinoma tumor to mice randomly divided in 4 groups 6 groups as follow : 1:tumor-control 2:tumor-continue training 3:tumor –continue training-Tamoxifen 4:tumor-interval training 5: tumor-interval training-Tamoxifen 6:tumor-tamoxifen. Continues training protocol was done for 6 weeks at 25% to 75% vo2max and interval training protocol was done for 6 weeks at 20% to 55%vot2 max between 1 until 10 interval rep *1 min . The drug was injected every day during research program. Blood samples were collected after protocol. The levels of Heat shock protein 70-kDa (Hsp70), interleukin 4 (IL-4), and interferon gamma (IFN γ) were measured with ELISA method, and the resulting data was analyzed with SPSS 10 statistical software Result: Data analysis showed that the Hsp70 levels in both groups of interval and interval plus Tamoxifen were decreased (P=0.459). Also in continues group was increased (p\u3e0/05).The IL-4 level in both groups of interval and interval plus Tamoxifen showed no significant differences compared to tumor control (P=0.112). The IFN γ level in both groups of interval and interval plus Tamoxifen showed an increase, but was not significant compared to control group(P=0.784). Conclusion: tumor mass in interval training only, interval training and Tamoxifen treated showed a significant decrease in the tumor growth in comparison with control group. But tumor mass in continues group was increased in comparison control group

The Ace of Spades: Reverse Takotsubo Cardiomyopathy in the Context of Angiographic Embolization of Recurrent Metastatic Serotonin-Positive Neuroendocrine Tumour of the Pancreas

A 62-year-old woman undergoing embolization of recurrent neuroendocrine tumor, positive for serotonin, developed chest pain and bradycardia with lateral ST-segment depression. Cardiac biomarkers were elevated, and echocardiography revealed akinesis of all basal segments with a normally contracting apex. The absence of flow-limiting coronary disease on angiography confirmed the presence of reverse Takotsubo cardiomyopathy. After optimal medical therapy for six weeks, left ventricular function returned to normal. Takotsubo cardiomyopathy has been described across a wide variety of hyperadrenergic states; the description of the reverse-type Takotsubo cardiomyopathy in the setting of embolization of recurrent neuroendocrine with serotonergic positivity tumour is novel

Ventricular arrhythmias and sudden death in adults after a Mustard operation for transposition of the great arteries

Aims To examine the prevalence of sustained ventricular tachycardia (VT) and sudden death (SD) in adults with atrial repair of transposition of the great arteries (TGA) and to determine associated risk factors. Methods and results In a single-centre review, we studied the outcome of 149 adults (mean age 28 ± 7 years) who had undergone a Mustard operation for TGA. During a mean follow-up of 9 ± 6 years, sustained VT and/or SD occurred in 9% (13/149) of the cohort. Sustained VT/SD was more likely to occur in patients with associated anatomic lesions [hazard ratio (HR) 4.9, 95% CI 1.5-16.0], with NYHA class ≥III (HR 9.8, 95% CI 3.0-31.6) and with an impaired subaortic right ventricular (RV) ejection fraction (EF) (HR 2.2, 95% CI 1.2-4.0 per 10% decrease in EF). There was an inverse correlation between the RV-EF and both age and QRS duration. Patients with a QRS duration ≥140 ms were at highest risk of sustained VT/SD (HR 13.6, 95% CI 2.9-63.4). Atrial tachyarrhythmia was detected in 66 (44%) patients, but was not a statistically significant predictor of sustained VT/SD in our adult population (HR 2.7, 95% CI 0.6-13.0). Conclusion Sustained VT/SD in adults after a Mustard operation for TGA are more common than previously described. Age, systemic ventricular function, and QRS duration are interrelated and are associated with VT/SD. A QRS duration ≥140 ms helps to identify the high risk patien

Cardiac outcomes in adults with supravalvar aortic stenosis

Aims Supravalvar aortic stenosis is a rare form of left ventricular outflow tract obstruction that is often progressive in childhood. Little data are available on outcomes in the adult population. Our aim was to define cardiac outcomes in adults with supravalvar aortic stenosis. Methods and results This is a multicentre retrospective study of cardiac outcomes in adults (≥18 years) with supravalvar aortic stenosis. We examined: (i) adverse cardiac events (cardiovascular death, myocardial infarction, stroke, heart failure, sustained arrhythmias, and infective endocarditis) and (ii) the need for cardiac surgery in adulthood. One hundred and thirteen adults (median age at first visit 19 years; 55% with Williams-Beuren syndrome; 67% with surgical repair in childhood) were identified. Adults without Williams-Beuren syndrome had more severe supravalvar aortic stenosis and more often associated left ventricular outflow tract obstructions (P < 0.001). In contrast, mitral valve regurgitation was more common in patients with Williams-Beuren syndrome. Eighty-five per cent of adults (96/113) had serial follow-up information (median follow-up 6.0 years). Of these patients, 13% (12/96) had an adverse cardiac event and 13% (12/96) had cardiac operations (7 valve repair or replacements, 4 supravalvar aortic stenosis repairs, 1 other). Cardiac surgery was more common in adults without Williams-Beuren syndrome (P = 0.007). Progression of supravalvar aortic stenosis during adulthood was rare. Conclusion Adults with supravalvar aortic stenosis remain at risk for cardiac complications and reoperations, while progression of supravalvar aortic stenosis in adulthood is rare. Valve surgery is the most common indication for cardiac surgery in adulthoo

Ventricular arrhythmias and sudden death in adults after a Mustard operation for transposition of the great arteries

AIMS: To examine the prevalence of sustained ventricular tachycardia (VT) and sudden death (SD) in adults with atrial repair of transposition of the great arteries (TGA) and to determine associated risk factors. METHODS AND RESULTS: In a single-centre review, we studied the outcome of 149 adults (mean age 28 +/- 7 years) who had undergone a Mustard operation for TGA. During a mean follow-up of 9 +/- 6 years, sustained VT and/or SD occurred in 9% (13/149) of the cohort. Sustained VT/SD was more likely to occur in patients with associated anatomic lesions [hazard ratio (HR) 4.9, 95% CI 1.5-16.0], with NYHA class >or=III (HR 9.8, 95% CI 3.0-31.6) and with an impaired subaortic right ventricular (RV) ejection fraction (EF) (HR 2.2, 95% CI 1.2-4.0 per 10% decrease in EF). There was an inverse correlation between the RV-EF and both age and QRS duration. Patients with a QRS duration >or=140 ms were at highest risk of sustained VT/SD (HR 13.6, 95% CI 2.9-63.4). Atrial tachyarrhythmia was detected in 66 (44%) patients, but was not a statistically significant predictor of sustained VT/SD in our adult population (HR 2.7, 95% CI 0.6-13.0). CONCLUSION: Sustained VT/SD in adults after a Mustard operation for TGA are more common than previously described. Age, systemic ventricular function, and QRS duration are interrelated and are associated with VT/SD. A QRS duration >or=140 ms helps to identify the high risk patient

Comparison of heart team vs interventional cardiologist recommendations for the treatment of patients with multivessel coronary artery disease

Abstract: Importance: Although the heart team approach is recommended in revascularization guidelines, the frequency with which heart team decisions differ from those of the original treating interventional cardiologist is unknown. Objective: To examine the difference in decisions between the heart team and the original treating interventional cardiologist for the treatment of patients with multivessel coronary artery disease. Design, setting, and participants: In this cross-sectional study, 245 consecutive patients with multivessel coronary artery disease were recruited from 1 high-volume tertiary care referral center (185 patients were enrolled through a screening process, and 60 patients were retrospectively enrolled from the center's database). A total of 237 patients were included in the final virtual heart team analysis. Treatment decisions (which comprised coronary artery bypass grafting, percutaneous coronary intervention, and medication therapy) were made by the original treating interventional cardiologists between March 15, 2012, and October 20, 2014. These decisions were then compared with pooled-majority treatment decisions made by 8 blinded heart teams using structured online case presentations between October 1, 2017, and October 15, 2018. The randomized members of the heart teams comprised experts from 3 domains, with each team containing 1 noninvasive cardiologist, 1 interventional cardiologist, and 1 cardiovascular surgeon. Cases in which all 3 of the heart team members disagreed and cases in which procedural discordance occurred (eg, 2 members chose coronary artery bypass grafting and 1 member chose percutaneous coronary intervention) were discussed in a face-to-face heart team review in October 2018 to obtain pooled-majority decisions. Data were analyzed from May 6, 2019, to April 22, 2020. Main outcomes and measures: The Cohen κ coefficient between the treatment recommendation from the heart team and the treatment recommendation from the original treating interventional cardiologist. Results: Among 234 of 237 patients (98.7%) in the analysis for whom complete data were available, the mean (SD) age was 67.8 (10.9) years; 176 patients (75.2%) were male, and 191 patients (81.4%) had stenosis in 3 epicardial coronary vessels. A total of 71 differences (30.3%; 95% CI, 24.5%-36.7%) in treatment decisions between the heart team and the original treating interventional cardiologist occurred, with a Cohen κ of 0.478 (95% CI, 0.336-0.540; P = .006). The heart team decision was more frequently unanimous when it was concordant with the decision of the original treating interventional cardiologist (109 of 163 cases [66.9%]) compared with when it was discordant (28 of 71 cases [39.4%]; P < .001). When the heart team agreed with the original treatment decision, there was more agreement between the heart team interventional cardiologist and the original treating interventional cardiologist (138 of 163 cases [84.7%]) compared with when the heart team disagreed with the original treatment decision (14 of 71 cases [19.7%]); P < .001). Those with an original treatment of coronary artery bypass grafting, percutaneous coronary intervention, and medication therapy, 32 of 148 patients [22.3%], 32 of 71 patients [45.1%], and 6 of 15 patients [40.0%], respectively, received a different treatment recommendation from the heart team than the original treating interventional cardiologist; the difference across the 3 groups was statistically significant (P = .002). Conclusions and relevance: The heart team's recommended treatment for patients with multivessel coronary artery disease differed from that of the original treating interventional cardiologist in up to 30% of cases. This subset of cases was associated with a lower frequency of unanimous decisions within the heart team and less concordance between the interventional cardiologists; discordance was more frequent when percutaneous coronary intervention or medication therapy were considered. Further research is needed to evaluate whether heart team decisions are associated with improvements in outcomes and, if so, how to identify patients for whom the heart team approach would be beneficial