Deficiency of mitochondrial calcium uniporter abrogates iron overload-induced cardiac dysfunction by reducing ferroptosis.

Iron overload associated cardiac dysfunction remains a significant clinical challenge whose underlying mechanism(s) have yet to be defined. We aim to evaluate the involvement of the mitochondrial Ca2+ uniporter (MCU) in cardiac dysfunction and determine its role in the occurrence of ferroptosis. Iron overload was established in control (MCUfl/fl) and conditional MCU knockout (MCUfl/fl-MCM) mice. LV function was reduced by chronic iron loading in MCUfl/fl mice, but not in MCUfl/fl-MCM mice. The level of mitochondrial iron and reactive oxygen species were increased and mitochondrial membrane potential and spare respiratory capacity (SRC) were reduced in MCUfl/fl cardiomyocytes, but not in MCUfl/fl-MCM cardiomyocytes. After iron loading, lipid oxidation levels were increased in MCUfl/fl, but not in MCUfl/fl-MCM hearts. Ferrostatin-1, a selective ferroptosis inhibitor, reduced lipid peroxidation and maintained LV function in vivo after chronic iron treatment in MCUfl/fl hearts. Isolated cardiomyocytes from MCUfl/fl mice demonstrated ferroptosis after acute iron treatment. Moreover, Ca2+ transient amplitude and cell contractility were both significantly reduced in isolated cardiomyocytes from chronically Fe treated MCUfl/fl hearts. However, ferroptosis was not induced in cardiomyocytes from MCUfl/fl-MCM hearts nor was there a reduction in Ca2+ transient amplitude or cardiomyocyte contractility. We conclude that mitochondrial iron uptake is dependent on MCU, which plays an essential role in causing mitochondrial dysfunction and ferroptosis under iron overload conditions in the heart. Cardiac-specific deficiency of MCU prevents the development of ferroptosis and iron overload-induced cardiac dysfunction.

Immunotherapeutics in lung cancers: from mechanistic insight to clinical implications and synergistic perspectives.

BACKGROUND: Lung cancer is one of the highly lethal forms of cancer whose incidence has worldwide rapidly increased over the past few decades. About 80-85% of all lung cancer cases constitute non-small cell lung cancer (NSCLC), with adenocarcinoma, squamous cell carcinoma and large cell carcinoma as the main subtypes. Immune checkpoint inhibitors have led to significant advances in the treatment of a variety of solid tumors, significantly improving cancer patient survival rates. METHODS AND RESULTS: The cytotoxic drugs in combination with anti-PD-(L)1 antibodies is a new method that aims to reduce the activation of immunosuppressive and cancer cell prosurvival responses while also improving direct cancer cell death. The most commonly utilized immune checkpoint inhibitors for patients with non-small cell lung cancer are monoclonal antibodies (Atezolizumab, Cemiplimab, Ipilimumab, Pembrolizumab etc.) against PD-1, PD-L1, and CTLA-4. Among them, Atezolizumab (TECENTRIQ) and Cemiplimab (Libtayo) are engineered monoclonal anti programmed death ligand 1 (PD-L1) antibodies that inhibit binding of PD-L1 to PD-1 and B7.1. As a result, T-cell proliferation and cytokine synthesis are inhibited leading to restoring the immune homeostasis to fight cancer cells. CONCLUSIONS: In this review article, the path leading to the introduction of immunotherapeutic options in lung cancer treatment is described, with analyzing the benefits and shortages of the current immunotherapeutic drugs. In addition, possibilities to co-administer immunotherapeutic agents with standard cancer treatment modalities are also considered.

Natural product-based nanoformulations for cancer therapy: Opportunities and challenges.

Application of natural product-based nanoformulations for the treatment of different human diseases, such as cancer, is an emerging field. The conventional cancer therapeutic modalities, including surgery, chemotherapy, immunotherapy, radiotherapy has limited achievements. A larger number of drawbacks are associated with these therapies, including damage to proliferating healthy tissues, structural deformities, systemic toxicity, long-term side effects, resistance to the drug by tumor cells, and psychological problems. The advent of nanotechnology in cancer therapeutics is recent; however, it has progressed and transformed the field of cancer treatment at a rapid rate. Nanotherapeutics have promisingly overcome the limitations of conventional drug delivery system, i.e., low aqueous solubility, low bioavailability, multidrug resistance, and non-specificity. Specifically, natural product-based nanoformulations are being intentionally studied in different model systems. Where it is found that these nanoformulations has more proximity and reduced side effects. The nanoparticles can specifically target tumor cells, enhancing the specificity and efficacy of cancer therapeutic modalities which in turn improves patient response and survival. The integration of phytotherapy and nanotechnology in the clinical setting may improve pharmacological response and better clinical outcome of patients.

STAT signaling as a target for intervention: from cancer inflammation and angiogenesis to non-coding RNAs modulation.

As a landmark, scientific investigation in cytokine signaling and interferon-related anti-viral activity, signal transducer and activator of transcription (STAT) family of proteins was first discovered in the 1990s. Today, we know that the STAT family consists of several transcription factors which regulate various molecular and cellular processes, including proliferation, angiogenesis, and differentiation in human carcinoma. STAT family members play an active role in transducing signals from cell membrane to nucleus through intracellular signaling and thus activating gene transcription. Additionally, they are also associated with the development and progression of human cancer by facilitating inflammation, cell survival, and resistance to therapeutic responses. Accumulating evidence suggests that not all STAT proteins are associated with the progression of human malignancy; however, STAT3/5 are constitutively activated in various cancers, including multiple myeloma, lymphoma, breast cancer, prostate hepatocellular carcinoma, and non-small cell lung cancer. The present review highlights how STAT-associated events are implicated in cancer inflammation, angiogenesis and non-coding RNA (ncRNA) modulation to highlight potential intervention into carcinogenesis-related cellular processes.

Reconstructive spectrometer using a photonic crystal cavity.

Optical spectrometers have propelled scientific and technological advancements in a wide range of fields. While sophisticated systems with excellent performance metrics are serving well in controlled laboratory environments, many applications require systems that are portable, economical, and robust to optical misalignment. Here, we propose and demonstrate a spectrometer that uses a planar one-dimensional photonic crystal cavity as a dispersive element and a reconstructive computational algorithm to extract spectral information from spatial patterns. The simple fabrication and planar architecture of the photonic crystal cavity render our spectrometry platform economical and robust to optical misalignment. The reconstructive algorithm allows miniaturization and portability. The intensity transmitted by the photonic crystal cavity has a wavelength-dependent spatial profile. We generate the spatial transmittance function of the system using finite-difference time-domain method and also estimate the dispersion relation. The transmittance function serves as a transfer function in our reconstructive algorithm. We show accurate estimation of various kinds of input spectra. We also show that the spectral resolution of the system depends on the cavity linewidth that can be improved by increasing the number of periodic layers in distributed Bragg mirrors. Finally, we experimentally estimate the center wavelength and linewidth of the spectrum of an unknown light emitting diode. The estimated values are in good agreement with the values measured using a commercial spectrometer.

Three-Dimensional Chemical Mapping of a Single Protein in the Hydrated State with Atom Probe Tomography.

Unravelling the three-dimensional structures and compositions of biological macromolecules sheds light on their functions and also contributes to the design of future biochemical compounds and processes. Atom probe tomography (APT) is demonstrated in this research as a new and effective approach to explore the structure and chemical composition of a single protein in the hydrated state. By introducing graphene encapsulation, proteins in solution can be immobilized on a metal specimen tip, with an end radius in the range of 50 nm to allow field ionization and evaporation. Using a ferritin particle as an example, analysis of the mass spectrum and reconstructed 3D chemical maps at near-atomic resolution acquired from APT reveals the core consisting of iron and iron oxides, the peptide shell containing amino acids, and the interior interface between the iron core and the peptide shell. The quantitative distribution and proportion of iron isotopes from a single ferritin core have been determined for the first time, as well as identification of the possible sites of amino acids inside the protein shell. The complete experimental protocol is straightforward and lays a foundation for future exploration of various macromolecules in a controlled environment.

Human Induced Pluripotent Stem Cell-Derived Cardiomyocytes as Models for Cardiac Channelopathies: A Primer for Non-Electrophysiologists.

Life threatening ventricular arrhythmias leading to sudden cardiac death are a major cause of morbidity and mortality. In the absence of structural heart disease, these arrhythmias, especially in the younger population, are often an outcome of genetic defects in specialized membrane proteins called ion channels. In the heart, exceptionally well-orchestrated activity of a diversity of ion channels mediates the cardiac action potential. Alterations in either the function or expression of these channels can disrupt the configuration of the action potential, leading to abnormal electrical activity of the heart that can sometimes initiate an arrhythmia. Understanding the pathophysiology of inherited arrhythmias can be challenging because of the complexity of the disorder and lack of appropriate cellular and in vivo models. Recent advances in human induced pluripotent stem cell technology have provided remarkable progress in comprehending the underlying mechanisms of ion channel disorders or channelopathies by modeling these complex arrhythmia syndromes in vitro in a dish. To fully realize the potential of induced pluripotent stem cells in elucidating the mechanistic basis and complex pathophysiology of channelopathies, it is crucial to have a basic knowledge of cardiac myocyte electrophysiology. In this review, we will discuss the role of the various ion channels in cardiac electrophysiology and the molecular and cellular mechanisms of arrhythmias, highlighting the promise of human induced pluripotent stem cell-cardiomyocytes as a model for investigating inherited arrhythmia syndromes and testing antiarrhythmic strategies. Overall, this review aims to provide a basic understanding of the electrical activity of the heart and related channelopathies, especially to clinicians or research scientists in the cardiovascular field with limited electrophysiology background.

Molecular Mechanisms of Action of Tocotrienols in Cancer: Recent Trends and Advancements.

Tocotrienols, found in several natural sources such as rice bran, annatto seeds, and palm oil have been reported to exert various beneficial health promoting properties especially against chronic diseases, including cancer. The incidence of cancer is rapidly increasing around the world not only because of continual aging and growth in global population, but also due to the adaptation of Western lifestyle behaviours, including intake of high fat diets and low physical activity. Tocotrienols can suppress the growth of different malignancies, including those of breast, lung, ovary, prostate, liver, brain, colon, myeloma, and pancreas. These findings, together with the reported safety profile of tocotrienols in healthy human volunteers, encourage further studies on the potential application of these compounds in cancer prevention and treatment. In the current article, detailed information about the potential molecular mechanisms of actions of tocotrienols in different cancer models has been presented and the possible effects of these vitamin E analogues on various important cancer hallmarks, i.e., cellular proliferation, apoptosis, angiogenesis, metastasis, and inflammation have been briefly analyzed.

Blockade of CaMKII depresses conduction preferentially in the right ventricular outflow tract and promotes ischemic ventricular fibrillation in the rabbit heart.

Calcium/calmodulin-dependent protein kinase II (CaMKII) regulates the principle ion channels mediating cardiac excitability and conduction, but how this regulation translates to the normal and ischemic heart remains unknown. Diverging results on CaMKII regulation of Na+ channels further prevent predicting how CaMKII activity regulates excitability and conduction in the intact heart. To address this deficiency, we tested the effects of the CaMKII blocker KN93 (1 and 2.75 µM) and its inactive analog KN92 (2.75 µM) on conduction and excitability in the left (LV) and right (RV) ventricles of rabbit hearts during normal perfusion and global ischemia. We used optical mapping to determine local conduction delays and the optical action potential (OAP) upstroke velocity (dV/dtmax). At baseline, local conduction delays were similar between RV and LV, whereas the OAP dV/dtmax was lower in RV than in LV. At 2.75 µM, KN93 heterogeneously slowed conduction and reduced dV/dtmax, with the largest effect in the RV outflow tract (RVOT). This effect was further exacerbated by ischemia, leading to recurrent conduction block in the RVOT and early ventricular fibrillation (at 6.7 ± 0.9 vs. 18.2 ± 0.8 min of ischemia in control, P < 0.0001). Neither KN92 nor 1 µM KN93 depressed OAP dV/dtmax or conduction. Rabbit cardiomyocytes isolated from RVOT exhibited a significantly lower dV/dtmax than those isolated from the LV. KN93 (2.75 µM) significantly reduced dV/dtmax in cells from both locations. This led to frequency-dependent intermittent activation failure occurring predominantly in RVOT cells. Thus CaMKII blockade exacerbates intrinsically lower excitability in the RVOT, which is proarrhythmic during ischemia.NEW & NOTEWORTHY We show that calcium/calmodulin-dependent protein kinase II (CaMKII) blockade exacerbates intrinsically lower excitability in the right ventricular outflow tract, which causes highly nonuniform chamber-specific slowing of conduction and facilitates ventricular fibrillation during ischemia. Constitutive CaMKII activity is necessary for uniform and safe ventricular conduction, and CaMKII block is potentially proarrhythmic.

Mitochondrial depolarization and asystole in the globally ischemic rabbit heart: coordinated response to interventions affecting energy balance.

Mitochondrial membrane potential (ΔΨm) depolarization has been implicated in the loss of excitability (asystole) during global ischemia, which is relevant for the success of defibrillation and resuscitation after cardiac arrest. However, the relationship between ΔΨm depolarization and asystole during no-flow ischemia remains unknown. We applied spatial Fourier analysis to confocally recorded fluorescence emitted by ΔΨm-sensitive dye tetramethylrhodamine methyl ester. The time of ischemic ΔΨm depolarization (tmito_depol) was defined as the time of 50% decrease in the magnitude of spectral peaks reflecting ΔΨm. The time of asystole (tasys) was determined as the time when spontaneous and induced ventricular activity ceased to exist. Interventions included tachypacing (150 ms), myosin II ATPase inhibitor blebbistatin (heart immobilizer), and the combination of blebbistatin and the inhibitor of glycolysis iodoacetate. In the absence of blebbistatin, confocal images were obtained during brief perfusion with hyperkalemic solution and after the contraction failed between 7 and 15 min of ischemia. In control, tmito_depol and tasys were 24.4 ± 6.0 and 26.0 ± 5.0 min, respectively. Tachypacing did not significantly affect either parameter. Blebbistatin dramatically delayed tmito_depol and tasys (51.4 ± 8.6 and 45.7 ± 5.3 min, respectively; both P < 0.0001 vs. control). Iodoacetate combined with blebbistatin accelerated both events (tmito_depol, 12.7 ± 1.8 min; and tasys, 6.5 ± 1.1 min; both P < 0.03 vs. control). In all groups pooled together, tasys was strongly correlated with tmito_depol (R(2) = 0.845; P < 0.0001). These data may indicate a causal relationship between ΔΨm depolarization and asystole or a similar dependence of the two events on energy depletion during ischemia. Our results urge caution against the use of blebbistatin in studies addressing pathophysiology of myocardial ischemia.

ß-Adrenergic stimulation and rapid pacing mutually promote heterogeneous electrical failure and ventricular fibrillation in the globally ischemic heart.

Global ischemia, catecholamine surge, and rapid heart rhythm (RHR) due to ventricular tachycardia or ventricular fibrillation (VF) are the three major factors of sudden cardiac arrest (SCA). Loss of excitability culminating in global electrical failure (asystole) is the major adverse outcome of SCA with increasing prevalence worldwide. The roles of catecholamines and RHR in the electrical failure during SCA remain unclear. We hypothesized that both ß-adrenergic stimulation (ßAS) and RHR accelerate electrical failure in the globally ischemic heart. We performed optical mapping of the action potential (OAP) in the right ventricular (RV) and left (LV) ventricular epicardium of isolated rabbit hearts subjected to 30-min global ischemia. Hearts were paced at a cycle length of either 300 or 200 ms, and either in the presence or in the absence of ß-agonist isoproterenol (30 nM). 2,3-Butanedione monoxime (20 mM) was used to reduce motion artifact. We found that RHR and ßAS synergistically accelerated the decline of the OAP upstroke velocity and the progressive expansion of inexcitable regions. Under all conditions, inexcitability developed faster in the LV than in the RV. At the same time, both RHR and ßAS shortened the time to VF (TVF) during ischemia. Moreover, the time at which 10% of the mapped LV area became inexcitable strongly correlated with TVF (R(2) = 0 .72, P < 0.0001). We conclude that both ßAS and RHR are major factors of electrical depression and failure in the globally ischemic heart and may contribute to adverse outcomes of SCA such as asystole and recurrent/persistent VF.

Osteopontin in cancer.

Osteopontin (OPN) is a heavily post-translationally modified protein with a molecular weight of 44-70 kDa, depending on the degree of glycosylation. OPN is involved in various biological processes, including bone remodeling, immune response, cell adhesion, migration, and survival. It is essential for controlling osteoclast and osteoblast activity for maintaining bone mass and bone strength. Additionally, OPN has been linked to cardiovascular, inflammatory illnesses, as well as the onset and progression of cancer. OPN is a multifunctional protein that can interact with a variety of cell surface receptors, such as integrins, CD44, the urokinase-type plasminogen activator receptor (uPAR), as well as extracellular matrix (ECM) components (e.g. collagen and hydroxyapatite). These interactions contribute to its wide range of biological functions in general and has significant implications for bone biology, immunology and cancer, specifically. In this chapter, we summarize the structure of OPN with a focus on its molecular mechanisms of action in various cancers.

A DFT study of the adsorption behavior and sensing properties of CO gas on monolayer MoSe2 in CO2-rich environment.

CONTEXT: Carbon monoxide, also known as the "silent killer," is a colorless, odorless, tasteless, and non-irritable gas that, when inhaled, enters the bloodstream and lungs, binds with the hemoglobin, and blocks oxygen from reaching tissues and cells. In this work, the monolayer MoSe2-based CO gas sensors were designed using density functional theory calculation with several dopants including Al, Au, Pd, Ni, Cu, and P. Here, Cu and P were found to be the best dopants, with adsorption energies of -0.67 eV (Cu) and -0.54 eV (P) and recovery times of 1.66 s and 13.8 ms respectively. Cu conductivity for CO adsorption was found to be 2.74 times that of CO2 adsorption in the 1.0-2.26 eV range. P displayed the highest selectivity, followed by Pd and Ni. The dopants, Pd and Ni, were found suitable for building CO gas scavengers due to their high recovery times of 9.76 × 1020 s and 2.47 × 1011 s. Similarly, the adsorption of CO2 on doped monolayer MoSe2 was also investigated. In this study, it is found that monolayer MoSe2 could be employed to create high-performance CO sensors in a CO2-rich environment. METHOD: The electrical characteristics of all doped MoSe2 monolayers are obtained using a DFT calculation with the PBE-GGA method from the Quantum ESPRESSO package. The self-consistent field (SCF) computations were performed using a 7 × 7 × 1 k-point grid and a norm-conserving pseudo potential (NCPP) file. To determine electrical conductivity, the semi-classical version of Boltzmann transport theory, implemented in the Boltz Trap code, was used.

ICA-105574 interacts with a common binding site to elicit opposite effects on inactivation gating of EAG and ERG potassium channels.

Rapid and voltage-dependent inactivation greatly attenuates outward currents in ether-a-go-go-related gene (ERG) K(+) channels. In contrast, inactivation of related ether-a-go-go (EAG) K(+) channels is very slow and minimally reduces outward currents. ICA-105574 (ICA, or 3-nitro-N-[4-phenoxyphenyl]-benzamide) has opposite effects on inactivation of these two channel types. Although ICA greatly attenuates ERG inactivation by shifting its voltage dependence to more positive potentials, it enhances the rate and extent of EAG inactivation without altering its voltage dependence. Here, we investigate whether the inverse functional response to ICA in EAG and ERG channels is related to differences in ICA binding site or to intrinsic mechanisms of inactivation. Molecular modeling coupled with site-directed mutagenesis suggests that ICA binds in a channel-specific orientation to a hydrophobic pocket bounded by the S5/pore helix/S6 of one subunit and S6 of an adjacent subunit. ICA is a mixed agonist of mutant EAG and EAG/ERG chimera channels that inactivate by a combination of slow and fast mechanisms. With the exception of three residues, the specific amino acids that form the putative binding pocket for ICA in ERG are conserved in EAG. Mutations introduced into EAG to replicate the ICA binding site in ERG did not alter the functional response to ICA. Together these findings suggest that ICA binds to the same site in EAG and ERG channels to elicit opposite functional effects. The resultant agonist or antagonist activity is determined solely by channel-specific differences in the mechanisms of inactivation gating.

Modulation of ventricular transient outward K⁺ current by acidosis and its effects on excitation-contraction coupling.

The contribution of transient outward current (Ito) to changes in ventricular action potential (AP) repolarization induced by acidosis is unresolved, as is the indirect effect of these changes on calcium handling. To address this issue we measured intracellular pH (pHi), Ito, L-type calcium current (ICa,L), and calcium transients (CaTs) in rabbit ventricular myocytes. Intracellular acidosis [pHi 6.75 with extracellular pH (pHo) 7.4] reduced Ito by ~50% in myocytes with both high (epicardial) and low (papillary muscle) Ito densities, with little effect on steady-state inactivation and activation. Of the two candidate α-subunits underlying Ito, human (h)Kv4.3 and hKv1.4, only hKv4.3 current was reduced by intracellular acidosis. Extracellular acidosis (pHo 6.5) shifted Ito inactivation toward less negative potentials but had negligible effect on peak current at +60 mV when initiated from -80 mV. The effects of low pHi-induced inhibition of Ito on AP repolarization were much greater in epicardial than papillary muscle myocytes and included slowing of phase 1, attenuation of the notch, and elevation of the plateau. Low pHi increased AP duration in both cell types, with the greatest lengthening occurring in epicardial myocytes. The changes in epicardial AP repolarization induced by intracellular acidosis reduced peak ICa,L, increased net calcium influx via ICa,L, and increased CaT amplitude. In summary, in contrast to low pHo, intracellular acidosis has a marked inhibitory effect on ventricular Ito, perhaps mediated by Kv4.3. By altering the trajectory of the AP repolarization, low pHi has a significant indirect effect on calcium handling, especially evident in epicardial cells.

Does the combination of hyperkalemia and KATP activation determine excitation rate gradient and electrical failure in the globally ischemic fibrillating heart?

Ventricular fibrillation (VF) in the globally ischemic heart is characterized by a progressive electrical depression manifested as a decline in the VF excitation rate (VFR) and loss of excitability, which occur first in the subepicardium (Epi) and spread to the subendocardium (Endo). Early electrical failure is detrimental to successful defibrillation and resuscitation during cardiac arrest. Hyperkalemia and/or the activation of ATP-sensitive K(+) (KATP) channels have been implicated in electrical failure, but the role of these factors in ischemic VF is poorly understood. We determined the VFR-extracellular K(+) concentration ([K(+)]o) relationship in the Endo and Epi of the left ventricle during VF in globally ischemic hearts (Isch group) and normoxic hearts subjected to hyperkalemia (HighK group) or a combination of hyperkalemia and the KATP channel opener cromakalim (HighK-Crom group). In the Isch group, Endo and Epi values of [K(+)]o and VFR were compared in the early (0-6 min), middle (7-13 min), and late (14-20 min) phases of ischemic VF. A significant transmural gradient in VFR (Endo > Epi) was observed in all three phases, whereas a significant transmural gradient in [K(+)]o (Epi > Endo) occurred only in the late phase of ischemic VF. In the Isch group, the VFR decrease and inexcitability started to occur at much lower [K(+)]o than in the HighK group, especially in the Epi. Combining KATP activation with hyperkalemia only shifted the VFR-[K(+)]o curve upward (an effect opposite to real ischemia) without changing the [K(+)]o threshold for asystole. We conclude that hyperkalemia and/or KATP activation cannot adequately explain the heterogeneous electrical depression and electrical failure during ischemic VF.

Patch-clamp technique to study mitochondrial membrane biophysics.

Mitochondria are double-membrane organelles crucial for oxidative phosphorylation, enabling efficient ATP synthesis by eukaryotic cells. Both of the membranes, the highly selective inner mitochondrial membrane (IMM) and a relatively porous outer membrane (OMM), harbor a number of integral membrane proteins that help in the transport of biological molecules. These transporters are especially enriched in the IMM, where they help maintain transmembrane gradients for H+, K+, Ca2+, PO43-, and metabolites like ADP/ATP, citrate, etc. Impaired activity of these transporters can affect the efficiency of energy-transducing processes and can alter cellular redox state, leading to activation of cell-death pathways or metabolic syndromes in vivo. Although several methodologies are available to study ion flux through membrane proteins, the patch-clamp technique remains the gold standard for quantitatively analyzing electrogenic ion exchange across membranes. Direct patch-clamp recordings of mitoplasts (mitochondria devoid of outer membrane) in different modes, such as whole-mitoplast or excised-patch mode, allow researchers the opportunity to study the biophysics of mitochondrial transporters in the native membrane, in real time, in isolation from other fluxes or confounding factors due to changes in ion gradients, pH, or mitochondrial potential (ΔΨ). Here, we summarize the use of patch clamp to investigate several membrane proteins of mitochondria. We demonstrate how this technique can be reliably applied to record whole-mitoplast Ca2+ currents mediated via mitochondrial calcium uniporter or H+ currents mediated by uncoupling protein 1 and discuss critical considerations while recording currents from these small vesicles of the IMM (mitoplast diameter = 2-5 µm).

Segregation of formulated powders in direct compression process and evaluations by small bench-scale testers.

Powder segregation can cause severe issues in processes of pharmaceutical drugs for control of content uniformity if the powder is likely to be free or easy flowing. Assessing segregation intensity of formulated powders in a process is challenging at the formulation stage because of the limited availability of samples. An advanced segregation evaluation using small bench-scale testers can be useful for formulation decisions and suggestions of operation conditions in the process, which has not been practically investigated before. In this study, eight formulations (two co-processed excipients blended with one active pharmaceutical ingredient at different ratios) were used for the segregation study on two types of bench-scale testers (air-induced and surface rolling segregation tester), and a pilot simulation process rig as a comparative study. The results show that segregation measured on the bench-scale testers can give a good indication of the segregation intensity of a blend if the segregation intensity is not more than 20%. The comparison also shows that both the bench-scale testers have a good correlation to the process rig, respectively, which means either segregation tester can be used independently for the evaluation. A linear regression model was explored for prediction of segregation in the process.

Stevens-johnson Syndrome and Toxic Epidermal Necrolysis: An Overview of Diagnosis, Therapy Options and Prognosis of Patients.

Both Stevens-johnson syndrome (SJS) and Toxic-epidermal necrolysis (TEN) are generally medication-induced pathological conditions that mostly affect the epidermis and mucus membranes. Nearly 1 to 2 patients per 1,000,000 population are affected annually with SJS and TEN, and sometimes these maladies can cause serious life-threatening events. The reported death rates for SJS range from 1 to 5%, and 25 to 35% for TEN. The mortality risk may even be higher among elderly patients, especially in those who are affected by a significant amount of epidermal detachment. More than 50% of TEN patients who survive the illness may experience long-term lower quality of life and lesser life expectancy. The clinical and histopathological conditions of SJS and TEN are characterized by mucocutaneous discomfort, haemorrhagic erosions, erythema, and occasionally severe epidermal separation that can turn into ulcerative patches and dermal necrosis. The relative difference between SJS and TEN is the degree of ulcerative skin detachment, making them two extremes of a spectrum of severe cutaneous adverse drug-induced reactions (cADRs). In the majority of cases, serious drug-related hypercreativities are considered the main cause of SJS & TEN; however, herpes simplex virus and Mycoplasma pneumoniae infections may also produce similar type clinical conditions. The aetiology of a lesser number of cases and their underlying causative factors remain unknown. Among the drugs with a 'greater likelihood' of causing TEN & SJS are carbamazepine (CBZ), trimethoprim-sulfamethoxazole, phenytoin, aminopenicillins, allopurinol, cephalosporins, sulphonamides, antibiotics, quinolones, phenobarbital, and NSAIDs of the oxicam variety. There is also a strong genetic link between the occurrence of SJS and IEN in the Han Chinese population. Such genetic association is based on the human leukocyte antigen (HLA-B*1502) and the co-administration of carbamazepine. The diagnosis of SJS is made mostly on the gross observations of clinical symptoms, and confirmed by the histopathological examination of dermal biopsies of the patients. The differential diagnoses consist of the exclusion of Pemphigus vulgaris, bullous pemphigoid, linear IgA dermatosis, paraneoplastic pemphigus, disseminated fixed bullous drug eruption, acute generalized exanthematous pustulosis (AGEP), and staphylococcal scalded skin syndrome (SSSS). The management of SJS & TEN is rather difficult and complicated, and there is sometimes a high risk of mortality in seriously inflicted patients. Urgent medical attention is needed for early diagnosis, estimation of the SCORTEN prognosis, identification and discontinuation of the causative agent as well as highdose injectable Ig therapeutic interventions along with specialized supportive care. Historical aspects, aetiology, mechanisms, and incidences of SJS and TEN are discussed. An update on the genetic occurrence of these medication-related hypersensitive ailments as well as different therapy options and management of patients is also provided.

Natural flavonoids exhibit potent anticancer activity by targeting microRNAs in cancer: A signature step hinting towards clinical perfection.

Cancer prevalence and its rate of incidence are constantly rising since the past few decades. Owing to the toxicity of present-day antineoplastic drugs, it is imperative to explore safer and more effective molecules to combat and/or prevent this dreaded disease. Flavonoids, a class of polyphenols, have exhibited multifaceted implications against several diseases including cancer, without showing significant toxicity towards the normal cells. Shredded pieces of evidence suggest that flavonoids can enhance drug sensitivity and suppress proliferation, metastasis, and angiogenesis of cancer cells by modulating several oncogenic or oncosuppressor microRNAs (miRNAs, miRs). They play pivotal roles in regulation of various biological and pathological processes, including various cancers. In the present review, the structure, chemistry and miR targeting efficacy of quercetin, luteolin, silibinin, genistein, epigallocatechin gallate, and cyanidin against several cancer types are comprehensively discussed. miRs are considered as next-generation medicine of recent times, and their targeting by naturally occurring flavonoids in cancer cells could be deemed as a signature step. We anticipate that our compilations related to miRNA-mediated regulation of cancer cells by flavonoids might catapult the clinical investigations and affirmation in the future.