Influence of surgery on the natural history of rheumatic mitral and aortic valve disease

The rate of survival, the evolution of functional cardiac status and the incidence of major complications during a 5 year period were studied in 410 patients with rheumatic mitral or aortic valve disease, of whom 200 were treated medically and 210 by surgery. The 5 year survival rates in patients with various types of rheumatic mitral valve disease were similar (45 percent for those with mitral stenosis and 46 percent for those with mitral insufficiency or mixed mitral insufficiency and stenosis). The survival rate in patients with aortic valve disease was somewhat more favorable (64 percent).Mitral valvulotomy had the most positive influence on mortality. The 85 percent 5 year survival rate of patients who underwent this procedure was significantly higher than that of patients with medically treated mitral stenosis. In patients submitted to mitral and aortic valve replacement, the survival rate was also improved in comparison with data in the corresponding medically treated groups, but to a lesser degree (70 percent for aortic valve replacement and 60 percent for mitral valve replacement). In all surgically treated groups, initial operative mortality was the primary determinant of the rate of survival at the end of 5 years.Survivors of all surgical groups had appreciable improvement in cardiac functional classification and a remarkable reduction in the incidence of heart failure and atrial fibrillation. The incidence of infectious endocarditis was significantly reduced after mitral valvulotomy, as compared with the incidence in patients with medically treated mitral stenosis. Mitral and aortic valve replacement did not reduce the incidence of infectious endocarditis. The incidence of thromboembolic phenomena was favorably influenced by mitral valvulotomy and aortic valve replacement, but not by mitral valve replacement.     

Highly aggressive early prosthetic endocarditis by S. epidermidis

Prosthetic valve endocarditis is considered to be 15% of all infectious endocarditis in developed countries, more frequently during the first 45 days after surgery. Between 45 and 60% of patients with prosthetic valve endocarditis present periannular involve. The aortic valve injury and early symptoms onset after surgery are related with a higher power of aggressive prosthetic endocarditis invasion. We present the case of a patient affected with early aortic prosthetic valve endocarditis by S. epidermidis with a high aggressive and proliferating course, accompanied by fistula to left atrial, severe aortic regurgitation and left atrial roof rupture detected at the time of surgery, along with interventricular membranous septal defect.     

Plasma concentration of asymmetric dimethylarginine,an endogenous inhibitor of nitric oxide synthase,is elevated in hyperthyroid patients

Cardiovascular manifestations are frequent findings in patients with thyroid hormone disorders. Nitric oxide (NO) plays a key role in vascular, endothelial-mediated relaxation. NO is synthesized from L-arginine by NO synthase, an enzyme inhibited by endogenous compounds, mainly asymmetric dimethylarginine [asymmetric N(G),N(G)-dimethyl-L-arginine (ADMA)]. The aim of our work was to investigate whether plasma L-arginine and dimethylarginine concentrations and NO production are altered in hypo- and hyperthyroid patients, compared with control subjects. L-arginine, ADMA and symmetric dimethylarginine were analyzed by HPLC. NO was measured as plasma nitrite plus nitrate (NO(x)) concentration by a colorimetric method based on Griess reagent. L-arginine, ADMA, and symmetric dimethylarginine plasma levels in the hypothyroid group were similar to those of the control group; whereas in hyperthyroidism, these values were significantly increased. However, the L-arginine/ADMA ratio was decreased in hyperthyroid patients, resulting in diminished NO(x) production. When all subjects were analyzed together, free T(4) levels were directly correlated with ADMA and inversely correlated with NO(x).     

U-46619-induced potentiation of noradrenergic constriction in the human saphenous vein: antagonism by thromboxane receptor blockade.

OBJECTIVE: We investigated the potentiating effect of U-46619, a synthetic analogue of thromboxane A(2) (TXA(2)), on the adrenergic responses in human saphenous vein. METHODS: Saphenous vein rings were obtained from 35 patients undergoing coronary artery bypass surgery. The rings were suspended in organ bath chambers for isometric recording of tension. RESULTS: U-46619 (10(-10)-3 x 10(-7) mol/l) produced concentration-dependent and endothelium-independent contractile responses. U-46619 (10(-10) mol/l) potentiated the contractions elicited by electrical stimulation and potassium chloride, and produced leftward shifts of the concentration-response curve for noradrenaline. The TXA(2) receptor antagonist SQ-30741 (10(-8) mol/l) prevented the potentiation evoked by U-46619. The dihydropyridine calcium antagonist nifedipine (10(-6) mol/l) did not affect the potentiation of electrical stimulation and noradrenaline induced by U-46619, but abolished the potentiation of U-46619 on KCl-induced contractions. CONCLUSIONS: U-46619 facilitates sympathetic neurotransmission and potentiates constrictor effects of noradrenaline in human saphenous veins through stimulation of TXA(2) receptors. These effects are independent of calcium entry through dihydropyridine calcium channels.     

Use of erythropoietin in emergencies: massive intoxication by chloramines

Recombinant human Erythropoietin (rHuEPO) is normally used to correct anaemia in patients with End Stage Renal Disease (ESRD), that are in Regular Dialysis Treatment (RDT). This anaemia is usually due to the existence of two factors: A decrease in the erythropoiesis of the bone marrow and an increase in peripheral haemolysis and, consequently, a decrease in the life span of the red cells.     

First report and molecular characterization of hepatitis E virus infection in renal transplant recipients in Brazil

Hepatitis E virus (HEV) causes acute and chronic hepatitis in organ transplant recipients. Serological evidence for HEV infection has been discovered in various population groups in Brazil, and a single acute case has been confirmed. To date, however, no cases of HEV infection in immunocompromised patients have been reported in Brazil. This study aimed to identify and characterize hepatitis E cases in renal transplant recipients in Brazil. A retrospective study was performed on 96 serum samples from renal transplant recipients with unexplained liver enzymes elevation. Three confirmed cases of HEV infection were identified that lacked seroconversion to HEV IgG antibodies. The prevalence of HEV in these patients was 3.1%. Using a sequence analysis of a 304‐nucleotide fragment within ORF2, the strains were classified as genotype 3 with a low percent identity to previously characterized strains. This is the first report of hepatitis E infection in renal transplant recipients in Brazil, and the data indicate that a novel genotype 3 subvariant may be present and that further investigation is necessary to characterize the circulating HEV strains. In this setting, HEV infection should be considered as a potential cause of abnormal liver tests of unknown origin. J. Med. Virol. 85:615–619, 2013. © 2013 Wiley Periodicals, Inc.     

Amyloid beta and the longest-lived rodent: the naked mole-rat as a model for natural protection from Alzheimer's disease

Amyloid beta (Aβ) is implicated in Alzheimer's disease (AD) as an integral component of both neural toxicity and plaque formation. Brains of the longest-lived rodents, naked mole-rats (NMRs) approximately 32 years of age, had levels of Aβ similar to those of the 3xTg-AD mouse model of AD. Interestingly, there was no evidence of extracellular plaques, nor was there an age-related increase in Aβ levels in the individuals examined (2–20+ years). The NMR Aβ peptide showed greater homology to the human sequence than to the mouse sequence, differing by only 1 amino acid from the former. This subtle difference led to interspecies differences in aggregation propensity but not neurotoxicity; NMR Aβ was less prone to aggregation than human Aβ. Nevertheless, both NMR and human Aβ were equally toxic to mouse hippocampal neurons, suggesting that Aβ neurotoxicity and aggregation properties were not coupled. Understanding how NMRs acquire and tolerate high levels of Aβ with no plaque formation could provide useful insights into AD, and may elucidate protective mechanisms that delay AD progression.     

Transitional Care for Young People with Neurological Disorders: A Scoping Review with A Focus on Patients with Movement Disorders

Childhood-onset movement disorders represent a heterogenous group of conditions. Given the complexity of these disorders, the transition of care from pediatric to adult medicine is an important consideration. We performed a scoping review of the literature on transitional care in chronic neurological disease, exploring key transitional issues and proposed transitional care models. Our aim was to describe the current knowledge and gaps about the transition process of young adults with chronic neurological disorders, paying special attention to childhood onset movement disorders. A total of 64 articles were included in the qualitative synthesis; 56 articles reported on transitional care issues, and 8 articles reported on transitional care models. Only 2 articles included patients with movement disorders. The following 4 main transitional issues were identified following synthesis of the available literature: (1) inadequate preparation for the transition process, (2) inappropriate and inconsistent transition practices, (3) inadequate adult services, and (4) heightened emotional response surrounding transition. Of the reported transitional care models, multidisciplinary ambulatory care was the most common approach. In studies evaluating patient-related outcomes, positive health, educational, and vocational outcomes were found. The available literature provides insights on issues that can arise during transition that should be addressed to improve patient and caregiver comfort and satisfaction with care. Further research is needed to evaluate how transitional care programs affect outcomes and their cost effectiveness. More studies are required to determine the needs and outcomes specific to patients with childhood onset movement disorders. © 2020 International Parkinson and Movement Disorder Society     

Influence of metabolic syndrome on post-stroke outcome,angiogenesis and vascular function in old rats determined by dynamic contrast enhanced MRI

Stroke affects primarily aged and co-morbid people, aspects not properly considered to date. Since angiogenesis/vasculogenesis are key processes for stroke recovery, we purposed to determine how different co-morbidities affect the outcome and angiogenesis/vasculogenesis, using a rodent model of metabolic syndrome, and by dynamic enhanced-contrast imaging (DCE-MRI) to assess its non-invasive potential to determine these processes. Twenty/twenty-two month-old corpulent (JCR:LA-Cp/Cp), a model of metabolic syndrome and lean rats were used. After inducing the experimental ischemia by transient MCAO, angiogenesis was analyzed by histology, vasculogenesis by determination of endothelial progenitor cells in peripheral blood by flow cytometry and evaluating their pro-angiogenic properties in culture and the vascular function by DCE-MRI at 3, 7 and 28 days after tMCAO. Our results show an increased infarct volume, BBB damage and an impaired outcome in corpulent rats compared with their lean counterparts. Corpulent rats also displayed worse post-stroke angiogenesis/vasculogenesis, outcome that translated in an impaired vascular function determined by DCE-MRI. These data confirm that outcome and angiogenesis/vasculogenesis induced by stroke in old rats are negatively affected by the co-morbidities present in the corpulent genotype and also that DCE-MRI might be a technique useful for the non-invasive evaluation of vascular function and angiogenesis processes.