Distinct cAMP Signaling Microdomains Differentially Regulate Melanosomal pH and Pigmentation.

cAMP signaling is a well-established regulator of melanin synthesis. Two distinct cAMP signaling pathways-the transmembrane adenylyl cyclase pathway, activated primarily by the MC1R, and the soluble adenylyl cyclase (sAC) pathway-affect melanin synthesis. The sAC pathway affects melanin synthesis by regulating melanosomal pH, and the MC1R pathway affects melanin synthesis by regulating gene expression and post-translational modifications. However, whether MC1R genotype affects melanosomal pH is poorly understood. We now report that loss of function MC1R does not affect melanosomal pH. Thus, sAC signaling appears to be the only cAMP signaling pathway that regulates melanosomal pH. We also addressed whether MC1R genotype affects sAC-dependent regulation of melanin synthesis. Although sAC loss of function in wild-type human melanocytes stimulates melanin synthesis, sAC loss of function has no effect on melanin synthesis in MC1R nonfunctional human and mouse melanocytes or skin and hair melanin in e/e mice. Interestingly, activation of transmembrane adenylyl cyclases, which increases epidermal eumelanin synthesis in e/e mice, leads to enhanced production of eumelanin in sAC-knockout mice relative to that in sAC wild-type mice. Thus, MC1R- and sAC-dependent cAMP signaling pathways define distinct mechanisms that regulate melanosomal pH and pigmentation.

Comparative Evaluation of Plasma Fibrinogen Degradation Product and Salivary Fibrin Precipitating Factor in Oral Submucous Fibrosis Patients and Betel Quid Chewers.

Aim and Objectives: Estimation and correlation of plasma fibrinogen degradation product (FDP) and salivary fibrin precipitating factor (FPF) in oral sub mucous fibrosis (OSMF) patients, betel quid chewers without OSMF and healthy individuals. The study aims to evaluate whether FDP and FPF can be used as a marker for development and progression of OSMF and whether there is any correlation between the two. Methodology: The study included 163 subjects grouped into three categories, Group 1, which included 54 control patients, Group 2, which included 55 betel quid chewers, and Group 3, which included 54 clinically confirmed OSMF patients. All of them were subjected to the estimation of plasma FDP and salivary FPF. Results: FDP was present in 52 (96.3%) patients in Group 3, 2 (3.6%) patients in Group 2, and 1 patient in Group 1 (1.9%). FPF was positive in eight patients. The correlation of FDP and FPF was done by Fisher's exact test and was found to be statistically nonsignificant. Conclusion: In the present study, FDP was positive in 52 (96.3%) OSMF patients; hence, FDP may be used as an early indicator of OSMF. FDP was found to be positive in two patients with a habit of chewing betel quid without OSMF. It may be hypothesized that these patients are more likely to develop OSMF. Hence, the estimation of FDP may be used as a diagnostic test to predict an impending OSMF before it could manifest itself clinically. FPF was negative in some OSMF patients, may be because it is below the detectable range.

Self-reported knowledge, attitudes, practices and barriers in use of evidence-based medicine among resident physicians in Kenya: a mixed methods study.

BACKGROUND: Evidence based medicine (EBM) helps clinicians to integrate latest research evidence into their daily clinical practice. There is a need for all healthcare professions to adopt it in order to provide safe and most cost-effective care. Postgraduate doctors are at the frontline of healthcare delivery and all medical institutions should strive to produce practitioners of EBM. Studies have shown that physicians are still struggling to adapt to this paradigm shift in the practice of medicine but very few studies have been done in Sub Saharan Africa. This study explored the self-reported knowledge, attitudes, practices and barriers of evidence-based practice among resident physicians in a tertiary teaching hospital. METHODS: A mixed methods cross-sectional study that used convergent parallel design was conducted. The quantitative arm was conducted among all residents enrolled in the Master of Medicine programme at Aga Khan University Hospital Nairobi (AKUHN). It included an online survey exploring self-reported knowledge, attitudes, practices and barriers of EBM among all residents. Simultaneously, semi-structured In-Depth Interviews were carried out among 18 purposefully selected residents in order to explore the same themes in more depth. RESULTS: One hundred and one residents (99%) responded to the survey. The mean scores for self-reported knowledge, attitude and practice of EBM among residents were 73.88, 66.96 and 63.19% respectively, which were generally higher than in comparable studies. There was a significant association between year of residency and practice of EBM. The most common barriers faced by residents were lack of time, lack of EBM skills and patients' unawareness about EBM. From the qualitative study, residents demonstrated good knowledge and support of EBM but practice remained relatively poor. Barriers to EBM were characterized by lack of motivation, time, skills and resources, patient overload and fear of challenging consultants. CONCLUSION: There was good understanding and support of EBM among residents at AKUHN, though challenges were experienced in regards to practice of EBM because of lack of time and skills. Therefore resources should be allocated towards integrating EBM into undergraduate medical curricula to cultivate critical thinking skills at an early stage before transition into residency.

Pediatric Dentistry during Coronavirus Disease-2019 Pandemic: A Paradigm Shift in Treatment Options.

Coronavirus disease-2019 (COVID-19) pandemic has affected the world in an aggressive manner and the healthcare fraternity has been at the forefront in this fight. Dental professionals are at a larger risk to get afflicted owing to the proximity to the oral cavity. Along with other verticals of dentistry, pediatric dentistry too has to adapt quickly keeping in mind the newer protocols so as to limit the increase of the global epidemic and the commencement of cross-infections. The purpose of this article is to present different treatment options for a pediatric dentist so as to achieve positive dental outcomes. HOW TO CITE THIS ARTICLE: Sharma A, Jain MB. Pediatric Dentistry during Coronavirus Disease-2019 Pandemic: A Paradigm Shift in Treatment Options. Int J Clin Pediatr Dent 2020;13(4):412-415.

Photocatalytic Degradation of Methyl Orange by Magnetically Retrievable Supported Ionic Liquid Phase Photocatalyst.

A magnetically retrievable ferrocene appended supported ionic liquid phase (SILP) photocatalyst containing a molybdate anion has been synthesized and characterized by Fourier transform infrared, X-ray photoelectron spectroscopy, transmission electron microscopy, X-ray diffraction, energy dispersive spectroscopy, and vibrating sample magnetometer analysis. The optical properties of the photocatalyst were probed by photoluminescence and UV-vis diffuse reflectance spectroscopy. The discharge of undesirable dye effluents from textile industrial plants in the environment is the major concern of environmental pollution and toxicity. In this context, we employed the as-prepared SILP photocatalyst for degradation of methyl orange (MO) under UV light (365 nm) irradiation, and subsequently, recycling studies were performed. The histological alteration in gills of the fish is employed as a tool for monitoring toxins in the environment. In view of this, the histo-toxicological assessment on freshwater fish Tilapia mossambica gills asserted the damage of secondary gill lamellae due to MO. Conversely, structural modifications in the gill architecture were not observed by virtue of photodegraded products confirming that the degraded product is nontoxic in nature. Additionally, the normal behavior of fishes on exposure to photodegraded products reveals that research findings are beneficial for the aquatic ecosystem.

Diagnosis and management of acute coronary syndrome: an evidence-based update.

Acute coronary syndrome (ACS) describes the range of myocardial ischemic states that includes unstable angina, non-ST elevated myocardial infarction (MI), or ST-elevated MI. ACS is associated with substantial morbidity and mortality and places a large financial burden on the health care system. The diagnosis of ACS begins with a thorough clinical assessment of a patient's presenting symptoms, electrocardiogram, and cardiac troponin levels as well as a review of past medical history. Early risk stratification can assist clinicians in determining whether an early invasive management strategy or an initial conservative strategy should be pursued and can help determine appropriate pharmacologic therapies. Key components in the management of ACS include coronary revascularization when indicated; prompt initiation of dual antiplatelet therapy and anticoagulation; and consideration of adjuvant agents including ß blockers, inhibitors of the renin angiotensin system, and HmG-coenzyme A reductase inhibitors. It is essential for clinicians to take an individualized approach to treatment and consider long-term safety and efficacy when managing patients with a history of ACS after hospital discharge.

Nonaqueous phase synthesis of copper nanoparticles.

Copper nanoparticles were synthesized in a nonaqueous solution of cetyltrimethylammonium bromide with isopropanol as a solvent. Cetyltrimethylammonium bromide in isopropanol is observed to play a role as a catalyst where isopropanol is the reducing agent. The surface plasmon band characteristic for Cu nanoparticles can be observed at approximately 560 nm in the UV-visible spectra at molar ratios for Cu2+: cetyltrimethylammonium bromide of 1:15 and 1:30. On the other hand, at molar ratios of 1:0.25 and 1:1 the presence of peak at approximately 310 nm can be attributed to oligomeric clusters of Cu0. Formation of Cu0 was further confirmed from the X-ray diffraction analysis. The diffractograms exhibited peaks at 2theta = approximately 41.6 degrees, approximately 51.6 degrees, and approximately 74.3 degrees, corresponding to Cu0. At lower concentration of cetyltrimethylammonium bromide (i.e., Cu2+: cetyltrimethylammonium bromide = 1:0.25) higher degree of size dispersity (particles between approximately 5-20 nm) can be noted from transmission electron micrograph. On the other hand, at the highest concentration of cetyltrimethylammonium bromide (i.e., Cu2+: cetyltrimethylammonium bromide = 1:30), formation of finer sized particles with a lower degree of size variation, approximately 2-10 nm, can be observed.