Functional characterization of a Ca2+-activated non-selective cation channel in human atrial cardiomyocytes

Cardiac arrhythmias, which occur in a wide variety of conditions where intracellular calcium is increased, have been attributed to the activation of a transient inward current ( I _ti). I _ti is the result of three different [Ca]_i-sensitive currents: the Na⁺–Ca²⁺ exchange current, a Ca²⁺-activated chloride current and a Ca²⁺-activated non-selective cationic current. Using the cell-free configuration of the patch-clamp technique, we have characterized the properties of a Ca²⁺-activated non-selective cation channel (NSC_Ca) in freshly dissociated human atrial cardiomyocytes. In excised inside-out patches, the channel presented a linear I–V relationship with a conductance of 19 ± 0.4 pS. It discriminated poorly among monovalent cations (Na⁺ and K⁺) and was slightly permeable to Ca²⁺ ions. The channel's open probability was increased by depolarization and a rise in internal calcium, for which the K _d for [Ca²⁺]_i was 20.8 μ m . Channel activity was reduced in the presence of 0.5 m m ATP or 10 μ m glibenclamide on the cytoplasmic side to 22.1 ± 16.8 and 28.5 ± 8.6%, respectively, of control. It was also inhibited by 0.1 m m flufenamic acid. The channel shares several properties with TRPM4b and TRPM5, two members of the 'TRP melastatin' subfamily. In conclusion, the NSC_Ca channel is a serious candidate to support the delayed after-depolarizations observed in [Ca²⁺] overload and thus may be implicated in the genesis of arrhythmias.     

Three months of COVID‐19: A systematic review and meta‐analysis

The pandemic of 2019 novel coronavirus (SARS‐CoV‐2019), reminiscent of the 2002‐SARS‐CoV outbreak, has completely isolated countries, disrupted health systems and partially paralyzed international trade and travel. In order to be better equipped to anticipate transmission of this virus to new regions, it is imperative to track the progress of the virus over time. This review analyses information on progression of the pandemic in the past 3 months and systematically discusses the characteristics of SARS‐CoV‐2019 virus including its epidemiologic, pathophysiologic, and clinical manifestations. Furthermore, the review also encompasses some recently proposed conceptual models that estimate the spread of this disease based on the basic reproductive number for better prevention and control procedures. Finally, we shed light on how the virus has endangered the global economy, impacting it both from the supply and demand side.     

Proposed model for in vitro interaction between fenitrothion and DNA,by using competitive fluorescence, 31P NMR, 1H NMR,FT-IR,CD and molecular modeling

In this work we proposed a model for in vitro interaction of fenitrothion (FEN) with calf thymus-DNA by combination of multispectroscopic and two dimensional molecular modeling (ONIOM) methods. The circular dichroism results showed that FEN changes the conformation of B-DNA and caused some changes to C-DNA form. The FT-IR results confirmed a partial intercalation between FEN and edges of all base pairs. The competitive fluorescence, using methylene blue as fluorescence probe, in the presence of increasing amounts of FEN, revealed that FEN is able to release the non-intercalated methylene blue from the DNA. The weak chemical shift and peak broadening of ¹H NMR spectrum of FEN in the presence of DNA confirmed a non-intercalation mode. The ³¹P NMR showed that FEN interacts more with DNA via its –NO₂ moiety. The ONIOM, based on the hybridization of QM/MM (DFT, 6.31++G (d,p)/UFF) methodology, was also performed by Gaussian 2003 package. The results revealed that the interaction is base sequence dependent, and FEN interacts more with AT base sequences.     

Meaning of Self-Care: Lived Experiences of Iranian Diabetic Patients

Background

Diabetes continuously disrupts a patient''s well-being and quality of life. Successful self-care could potentially decrease overall costs and rates of mortality and morbidity. Patients'' experiences could be used to elucidate what they believe about illness and its management. The overall aim of this study was to illuminate the meaning of self-care among diabetic patients in Southeast of Iran.

Methods

Sixteen diabetic patients with a mean age of 34 and 10 years'' experience in self-care for their disease were interviewed. The interviews were recorded, transcribed verbatim, and analyzed with a Ricoeur''s phenomenological hermeneutic method.

Results

The meaning of self- care was comprehensively understood as being empowered. This can be divided into four themes: seeking information, being independent, being optimistic or pessimistic and trust in God.

Conclusion

The results in this study suggest that cultural and religious components could affect diabetic patients'' self-care. Nurses might use patients'' religious beliefs to relieve their stress, help them to retain a sense of control, maintain hope and sense of meaning and purpose in their life.     

Idiopathic aneurysm of the pulmonary artery trunk. Report of a case

Aneurysms of the aorta are frequent and treatment is well known, correlated with a statistical risk of rupture. Pulmonary artery aneurysms are less frequent. They may occur in connection with other conditions (infection, cardiopathy, notably pulmonary artery hypertension, endovascular trauma) or much more exceptionally regarded as idiopathic. Chest x-ray, CT-scan and digitalized pulmonary angiography and echocardiography give the diagnosis and help evaluate extension and localization. We report the case of a 72-year-old woman who developed idiopathic aneurysm of the left pulmonary artery which was discovered fortuitously. Because of the stability of the lesion and the lack of any worsening factor, we decided not to operate this high-risk patient. After 3 years, no complication has been observed and the CT-scan shows no evolution. In case of proximal idiopathic aneurysm of the pulmonary artery, the indication of surgery should be discussed.     

Evaluation of the FASTPlaqueTB assay for direct detection of Mycobacterium tuberculosis in sputum specimens.

SETTING: Sputum samples were collected from suspected tuberculosis patients attending out-patient clinics at the Ojha Institute of Chest Diseases, Karachi, Pakistan. OBJECTIVE: To evaluate the performance of the FASTPlaqueTB assay for rapid diagnosis of pulmonary tuberculosis. DESIGN: A comparative study of 584 sputum samples using acid-fast smear microscopy, Lowenstein-Jensen culture and FASTPlaqueTB. RESULTS: A total of 514 samples yielded complete results. Seventy specimens were lost to analysis due to the overgrowth of contaminants. The addition of antimicrobials inhibited growth of gram-positive contaminants, and reduced the overall contamination rate from 18.2% to 7.2%. Mycobacterium tuberculosis was isolated from 175 smear-positive and 70 smear-negative specimens. FASTPlaqueTB detected M. tuberculosis in 81.6% of specimens, with a specificity of 97.7%. The sensitivity and specificity of the assay for smear-positive specimens were respectively 87.4% and 88.2%. For smear-negative specimens, the sensitivity of the assay was 67.1% and the specificity was 98.4%. The combined sensitivity of smear and FASTPlaqueTB for M. tuberculosis was 90%. Test results were available in 48 hours. CONCLUSION: FASTPlaqueTB is a sensitive and specific test for rapid diagnosis of pulmonary tuberculosis in high prevalence areas. The test is sensitive enough to confirm a large number of clinically suspected smear-negative cases and improve case finding.     

Cardiogenic shock due to myocardial infarction: surgical revascularization with centrifugal left ventricular assistance. Report of 2 cases treated successfully

Cardiogenic shock in the acute phase of myocardial infarction still carries a high mortality. In young patients who cannot be revascularised by angioplasty, when medical therapy is failing, some workers recommend an energetic approach, even cardiac transplantation, often with the bridge of mechanical cardiac assistance. This is not possible everywhere, thus preventing possible myocardial salvage and resulting in fairly high mortality. The authors report two cases in which endoluminal revascularisation was not possible and so complete surgical revascularisation with left ventricular assistance was chosen. The two patients survived and one was successfully transplanted electively. This management may be proposed in young patients with multiple occlusions of large coronary arteries in post-infarction cardiogenic shock when medical management is failing despite intra-aortic balloon pumping.     

What works? Interventions for maternal and child undernutrition and survival

We reviewed interventions that affect maternal and child undernutrition and nutrition-related outcomes. These interventions included promotion of breastfeeding; strategies to promote complementary feeding, with or without provision of food supplements; micronutrient interventions; general supportive strategies to improve family and community nutrition; and reduction of disease burden (promotion of handwashing and strategies to reduce the burden of malaria in pregnancy). We showed that although strategies for breastfeeding promotion have a large effect on survival, their effect on stunting is small. In populations with sufficient food, education about complementary feeding increased height-for-age Z score by 0.25 (95% CI 0.01-0.49), whereas provision of food supplements (with or without education) in populations with insufficient food increased the height-for-age Z score by 0.41 (0.05-0.76). Management of severe acute malnutrition according to WHO guidelines reduced the case-fatality rate by 55% (risk ratio 0.45, 0.32-0.62), and recent studies suggest that newer commodities, such as ready-to-use therapeutic foods, can be used to manage severe acute malnutrition in community settings. Effective micronutrient interventions for pregnant women included supplementation with iron folate (which increased haemoglobin at term by 12 g/L, 2.93-21.07) and micronutrients (which reduced the risk of low birthweight at term by 16% (relative risk 0.84, 0.74-0.95). Recommended micronutrient interventions for children included strategies for supplementation of vitamin A (in the neonatal period and late infancy), preventive zinc supplements, iron supplements for children in areas where malaria is not endemic, and universal promotion of iodised salt. We used a cohort model to assess the potential effect of these interventions on mothers and children in the 36 countries that have 90% of children with stunted linear growth. The model showed that existing interventions that were designed to improve nutrition and prevent related disease could reduce stunting at 36 months by 36%; mortality between birth and 36 months by about 25%; and disability-adjusted life-years associated with stunting, severe wasting, intrauterine growth restriction, and micronutrient deficiencies by about 25%. To eliminate stunting in the longer term, these interventions should be supplemented by improvements in the underlying determinants of undernutrition, such as poverty, poor education, disease burden, and lack of women's empowerment.     

Serum adenosine deaminase may predict disease activity in rheumatoid arthritis

To determine the relationship between serum adenosine deaminase (ADA) and disease activity, and to develop a new disease activity index based on serum ADA in rheumatoid arthritis (RA). Seventy RA patients were included. Disease activity based on Disease Activity Score 28-ESR (DAS28-ESR) and Disease Activity Score 28-CRP (DAS28-CRP) and serum ADA were measured. There were correlations when serum ADA compared with DAS28-ESR and DAS28-CRP. (R ²?=?0.014, 0.175, respectively, P values?<?0.00). New disease activity index was developed by replacing ADA with ESR and CRP in DAS28-ESR and DAS28-CRP. There were strong correlations when new model compared with DAS28-ESR and DAS28-CRP. (R ²?=?0.94 and 0.95, respectively, P values?<?0.00) The best new model values corresponding to DAS28-ESR values of 2.6, 3.2, and 5.1 were 2.79, 3.4, and 4.82, respectively; and new model values corresponding to DAS28-CRP values of 2.3, 2.7, and 4.1 were 2.1, 2.9, and 4, respectively. There were agreements when the new model compared with DAS28-ESR and DAS28-CRP for determination of patients in different disease activity categories. (Kappa?=?0.81 and 0.71, respectively, P values?<?0.00). The new disease activity index that applies serum ADA may help in predicting disease activity in RA.