Dynamin-like proteins mediate extracellular vesicle secretion in Mycobacterium tuberculosis.

Mycobacterium tuberculosis (Mtb) secretes extracellular vesicles (EVs) containing a variety of proteins, lipoproteins, and lipoglycans. While emerging evidence suggests that EVs contribute to tuberculosis pathogenesis, the factors and molecular mechanisms involved in mycobacterial EV production have not been identified. In this study, we use a genetic approach to identify Mtb proteins that mediate vesicle release in response to iron limitation and antibiotic exposure. We uncover a critical role for the isoniazid-induced, dynamin-like proteins, IniA and IniC, in mycobacterial EV biogenesis. Further characterization of a Mtb iniA mutant shows that the production of EVs enables intracellular Mtb to export bacterial components into the extracellular environment to communicate with host cells and potentially modulate the immune response. The findings advance our understanding of the biogenesis and functions of mycobacterial EVs and provide an avenue for targeting vesicle production in vivo.

Innovations in dengue virus detection: An overview of conventional and electrochemical biosensor approaches.

Globally, people are in great threat due to the highly spreading of viral infectious diseases. Every year like 100-300 million cases of infections are found, and among them, above 80% are not recognized and irrelevant. Dengue virus (DENV) is an arbovirus infection that currently infects people most frequently. DENV encompasses four viral serotypes, and they each express comparable sign. From a mild febrile sickness to a potentially fatal dengue hemorrhagic fever, dengue can induce a variety of symptoms. Presently, the globe is being challenged by the untimely identification of dengue infection. Therefore, this review summarizes advances in the detection of dengue from conventional methods (nucleic acid-based, polymerase chain reaction-based, and serological approaches) to novel biosensors. This work illustrates an extensive study of the current designs and fabrication approaches involved in the formation of electrochemical biosensors for untimely identifications of dengue. Additionally, in electrochemical sensing of DENV, we skimmed through significances of biorecognition molecules like lectins, nucleic acid, and antibodies. The introduction of emerging techniques such as the CRISPR/Cas' system and their integration with biosensing platforms has also been summarized. Furthermore, the review revealed the importance of electrochemical approach compared with traditional diagnostic methods.

In the Loop: Endovascular Pedal Arch Revascularization.

Advanced endovascular techniques are increasingly being utilized to treat patients with peripheral arterial disease and chronic limb-threatening ischemia to improve lower extremity arterial perfusion. In diabetic patients, pedal arch patency has been associated with improved wound healing, limb salvage, and overall survival. Pedal-plantar loop revascularization is a technique that can restore arterial inflow between the dorsal and plantar arteries of the foot. This article will describe the inframallelolar arterial anatomy and focus on imaging, percutaneous endovascular techniques, and clinical study outcomes of pedal artery interventions.

Intranasal Rotenone Induces Alpha-Synuclein Accumulation, Neuroinflammation and Dopaminergic Neurodegeneration in Middle-Aged Mice.

Accumulation of alpha-synuclein (α-syn) is central to the pathogenesis of Parkinson's disease (PD). Previous studies suggest that α-syn pathology may originate from the olfactory bulb (OB) or gut in response to an unknown pathogen and later progress to the different brain regions. Aging is viewed as the utmost threat to PD development. Therefore, studies depicting the role of age in α-syn accumulation and its progression in PD are important. In the present study, we gave intranasal rotenone microemulsion for 6 weeks in 12-month-old female BALB/c mice and found olfactory dysfunction after 4 and 6 weeks of rotenone administration. Interestingly, motor impairment was observed only after 6 weeks. The animals were sacrificed after 6 weeks to perform western blotting and immunohistochemical studies to detect α-syn pathology, neuroinflammation and neurodegeneration. We found α-syn accumulation in OB, striatum, substantia nigra (SN) and cortex. Importantly, we found significant glial cell activation and neurodegeneration in all the analysed regions which were absent in our previous published studies with 3 months old mice even after they were exposed to rotenone for 9 weeks indicating age is a crucial factor for α-syn induced neuroinflammation and neurodegeneration. We also observed increased iron accumulation in SN of rotenone-exposed aged mice. Moreover, inflammaging was observed in OB and striatum of 12-month-old BALB/c mice as compared to 3-month-old BALB/c mice. In conclusion, there is a difference in sensitivity between adult and aged mice in the development and progression of α-syn pathology and subsequent neurodegeneration, for which inflammaging might be the crucial probable mechanism.

AMPK-dependent autophagy activation and alpha-Synuclein clearance: a putative mechanism behind alpha-mangostin's neuroprotection in a rotenone-induced mouse model of Parkinson's disease.

Alpha-Synuclein (α-Syn) accumulation is central to the pathogenesis of Parkinson's disease (PD), hence the quest for finding potential therapeutics that may promote the α-Syn clearance is the need of the hour. To this, activation of the evolutionarily conserved protein and key regulator of the autophagy, 5'AMP-activated protein kinase (AMPK) is well-known to induce autophagy and subsequently the clearance of α-Syn aggregates. Alpha-mangostin (AM) a polyphenolic xanthone obtained from Garcinia Mangostana L. was previously reported to activate AMPK-dependent autophagy in various pre-clinical cancer models. However, no studies evidenced the effect of AM on AMPK-dependent autophagy activation in the PD. Therefore, the present study aimed to investigate the neuroprotective activity of AM in the chronic rotenone mouse model of PD against rotenone-induced α-Syn accumulation and to dissect molecular mechanisms underlying the observed neuroprotection. The findings showed that AM exerts neuroprotection against rotenone-induced α-Syn accumulation in the striatum and cortex by activating AMPK, upregulating autophagy (LC3II/I, Beclin-1), and lysosomal (TFEB) markers. Of note, an in-vitro study utilizing rat pheochromocytoma cells verified that AM conferred the neuroprotection only through AMPK activation, as the presence of inhibitors of AMPK (dorsomorphin) and autophagy (3-methyl adenine) failed to mitigate rotenone-induced α-Syn accumulation. Moreover, AM also counteracted rotenone-induced behavioral deficits, oxidative stress, and degeneration of nigro-striatal dopaminergic neurons. In conclusion, AM provided neuroprotection by ameliorating the rotenone-induced α-Syn accumulation through AMPK-dependent autophagy activation and it can be considered as a therapeutic agent which might be having a higher translational value in the treatment of PD.

COVID-19 presenting as acute pancreatitis.

The ongoing pandemic of Coronavirus disease-2019 (COVID-19) has spread over 200 countries worldwide, affecting >2 million people and >120,000 deaths. COVID-19 is caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). The most common symptoms include cough, shortness of breath, and fever. However, gastrointestinal manifestations of COVID-19 are increasingly being recognized. Herein, we report a case of COVID-19 who presented with acute pancreatitis (AP) without any other risk factors.

Dynamics of a gas-phase SNAr reaction: non-concerted mechanism despite the Meisenheimer complex being a transition state.

The commonly accepted mechanism of the nucleophilic aromatic substitution (SNAr) reaction has been found to be governed by the nature of the Meisenheimer structure on the potential energy surface. A stable Meisenheimer intermediate favors a stepwise mechanism, while a Meisenheimer transition state favors a concerted mechanism. Here, we show by using a detailed potential energy map (using the DFT and DLPNO-CCSD(T)/CBS methods) and ab initio classical trajectory simulations that the F- + C6H5NO2 SNAr reaction involves a Meisenheimer transition state and follows a stepwise mechanism in contrast to the expected concerted pathway. The stepwise mechanism observed in the trajectory simulations takes place by the formation of various ion-dipole and σ-complexes. While the majority of the trajectories follow the multi-step mechanism and avoid the minimum energy path, a considerable fraction exhibit a roaming atom mechanism where the F atom hovers around the phenyl ring before the formation of the products.

Classical Dynamics Simulations of Dissociation of Protonated Tryptophan in the Gas Phase.

Gas phase decomposition of protonated amino acids are of great interest due to their role in understanding protein and peptide chemistry. Several experimental and theoretical studies have been reported in the literature on this subject. In the present work, decomposition of the aromatic amino acid protonated tryptophan was studied by on-the-fly classical chemical dynamics simulations using density functional theory. Mass spectrometry and electronic structure theory studies have shown multiple dissociation pathways for this biologically relevant molecule. Unlike aliphatic amino acids, protonated tryptophan dissociates via NH3 elimination rather than the usual iminium ion formation by combined removal of H2O and CO molecules. Also, a major fragmentation pathway in the present work involves Cα-Cß bond fission. Results of the chemical dynamics simulations reported here are in overall agreement with experiments, and detailed atomic level mechanisms are presented.

Mechanisms and dynamics of protonation and lithiation of ferrocene.

By elucidating the mechanism of the simplest electrophilic substitution reaction of ferrocene, it was found that the verification of the protonation reaction has been a difficulty. In the work reported here, ab initio chemical dynamics simulations were performed at B3LYP/DZVP level of theory to understand the atomic level mechanisms of protonation and lithiation of ferrocene. Protonation of ferrocene resulted in the agostic and metal-protonated forms. Trajectory calculations revealed that protonation of ferrocene occurs by exo and endo mechanisms, with exo being the major path. H(+) was found to be mobile and hopped from the Cp ring to the metal center and vice versa after the initial attack on ferrocene, with the metal-complex having a shorter lifetime. These results remove the ambiguity surrounding the mechanism, as proposed in earlier experimental and computational studies. Lithiation of ferrocene resulted in the formation of cation-π and metal-lithiated complexes. Similar to protonation, trajectory results revealed that both exo and endo paths were followed, with the exo path being the major one. In addition, lithiated-ferrocene exhibited planetary motion. The major path (exo) followed in the protonation and lithiation of ferrocene is consistent with the observations in earlier experimental studies for other hard electrophiles.

Impact of Vitiligo on Quality of Life in Patients of Skin of Color and Its Correlation With Clinical Severity Assessment Scores Utilizing Disease Specific Scores: A Cross-Sectional Study.

INTRODUCTION: Assessment of disease severity of vitiligo is exigent as it is a psychosomatic ailment. VIDA (vitiligo disease activity score) and VASI (vitiligo area severity index) were previously used for this evaluation. Recently, the introduction of two vitiligo specific tools, vitiligo impact scale (VIS)-22 and Vitiligo Quality of Life Index (VitiQoL) has aided in assessing the quality of life (QOL) in a pertinent manner. OBJECTIVES: To measure the QOL in vitiligo using disease specific indices (VitiQoL and VIS-22), to assess their relationship with disease severity (VASI and VIDA) and to determine the correlation between QOL scores (VIS-22 and VitiQoL). METHODS: This observational cross-sectional study included 195 patients with vitiligo, and their disease severity was calculated using VASI and VIDA scoring. Patients were asked to fill questionnaires for assessing the QOL using validated tools i.e. VIS-22 and VitiQoL. RESULTS: Significant correlation was demonstrated between both QOL scores and VASI score (P value 0.001) with slightly higher values for VitiQoL (r = 0.824) than with VIS 22 (r = 0.693). Both scores exhibited a significant association with VIDA score (P value < 0.001). Moreover, statistically significant correlation was found between VIS-22 and VitiQoL, thereby proving the concordance between these scores. CONCLUSIONS: The study infers that QOL seemed to be remarkably dependent on the clinical severity scores and that higher disease activity corresponds to poorer QOL. It is imperative to precisely assess burden of vitiligo and the impairments caused by it in order to aid multi-modality management and allow more standardized research.

Practical Review of Necrotizing Fasciitis: Principles and Evidence-based Management.

Necrotizing fasciitis is a severe, life-threatening soft tissue infection that presents as a surgical emergency. It is characterized by a rapid progression of inflammation leading to extensive tissue necrosis and destruction. Nonetheless, the diagnosis might be missed or delayed due to variable and nonspecific clinical presentation, contributing to high mortality rates. Therefore, early diagnosis and prompt, aggressive medical and surgical treatment are paramount. In this review, we highlight the defining characteristics, pathophysiology, diagnostic modalities, current principles of treatment, and evolving management strategies of necrotizing fasciitis.

Automated detection of depression using wavelet scattering networks.

Today, depression is a common problem that affects many people all over the world. It can impact a person's mood and quality of life unless identified and treated immediately. Due to the hectic and stressful modern life seems to be, depression has become a leading cause of mental health illnesses. Signals from electroencephalograms (EEG) are frequently used to detect depression. It is difficult, time-consuming, and highly skilled to manually detect depression using EEG data analysis. Hence, in the proposed study, an automated depression detection system using EEG signals is proposed. The proposed study uses a clinically available dataset and dataset provided by the Department of Psychiatry at the Government Medical College (GMC) in Kozhikode, Kerala, India which consisted of 15 depressed patients and 15 healthy subjects and a publically available Multi-modal Open Dataset (MODMA) for Mental-disorder Analysis available at UK Data service reshare that consisted of 24 depressed patients and 29 healthy subjects. In this study, we have developed a novel Deep Wavelet Scattering Network (DWSN) for the automated detection of depression EEG signals. The best-performing classifier is then chosen by feeding the features into several machine-learning algorithms. For the clinically available GMC dataset, Medium Neural Network (MNN) achieved the highest accuracy of 99.95% with a Kappa value of 0.999. Using the suggested methods, the precision, recall, and F1-score are all 1. For the MODMA dataset, Wide Neural Network (WNN) achieved the highest accuracy of 99.3% with a Kappa value of 0.987. Using the suggested methods, the precision, recall, and F1-score are all 0.99. In comparison to all current methodologies, the performance of the suggested research is superior. The proposed method can be used to automatically diagnose depression both at home and in clinical settings.

Low-flow, Low-gradient Severe Aortic Stenosis: A Review.

Aortic stenosis (AS) is a common valve pathology experienced by patients worldwide. There are limited population-based studies assessing its prevalence; however, epidemiological studies emphasize that the burden of disease is growing. Recognizing AS relies on accurate clinical assessment and diagnostic investigations. Patients who develop severe AS are often referred to the heart team for assessment of aortic valve intervention. Although echocardiography has traditionally been used to screen and monitor the progression of AS, there can be discordance between measurements in a low-flow state. Such patients may have truly severe AS and potentially derive long-term benefit from aortic valve intervention. Accurately identifying these patients with the use of ancillary testing has been the focus of research for several years. In this article, we discuss the contemporary approaches and challenges in identifying and managing patients with low-flow, low-gradient severe AS.

Neuroprotective Effect of Swertiamarin in a Rotenone Model of Parkinson's Disease: Role of Neuroinflammation and Alpha-Synuclein Accumulation.

Parkinson's disease (PD) is a progressive neurodegenerative disease with no permanent cure affecting around 1% of the population over 65. There is an urgency to search for a disease-modifying agent with fewer untoward effects. PD pathology involves the accumulation of toxic alpha-synuclein (α-syn) and neuronal inflammation leading to the degeneration of dopaminergic (DAergic) neurons. Swertiamarin (SWE), a well-studied natural product, possesses a strong anti-inflammatory effect. It is a secoiridoid glycoside isolated from Enicostemma littorale Blume. SWE showed a reversal effect on the α-syn accumulation in the 6-hydroxydopamine (6-OHDA)-induced Caenorhabditis elegans model of PD. However, there are no reports in the literature citing the effect of SWE as a neuroprotective agent in rodents. The present study aimed to evaluate the anti-inflammatory activity of SWE against lipopolysaccharide (LPS)-induced C6 glial cell activation and its neuroprotective effect in the intrastriatal rotenone mouse PD model. SWE treatment showed a significant reduction in interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), and interleukin-1ß (IL-1ß) levels in LPS-induced C6 glial cell activation. Further, our studies demonstrated the suppression of microglial and astroglial activation in substantia nigra (SN) after administration of SWE (100 mg/kg, intraperitoneally) in a rotenone mouse model. Moreover, SWE alleviated the rotenone-induced α-syn overexpression in the striatum and SN. SWE ameliorated the motor impairment against rotenone-induced neurotoxicity and mitigated the loss of DAergic neurons in the nigrostriatal pathway. Therefore, SWE has the potential to develop as an adjunct therapy for PD, but it warrants further mechanistic studies.

Enrichment of Native and Recombinant Extracellular Vesicles of Mycobacteria.

Most bacteria, including mycobacteria, generate extracellular vesicles (EVs). Since bacterial EVs (bEVs) contain a subset of cellular components, including metabolites, lipids, proteins, and nucleic acids, several groups have evaluated either the native or recombinant versions of bEVs for their protective potency as subunit vaccine candidates. Unlike native EVs, recombinant EVs are molecularly engineered to contain one or more immunogens of interest. Over the last decade, different groups have explored diverse approaches for generating recombinant bEVs. However, here, we report the design, construction, and enrichment of recombinant mycobacterial EVs (mEVs) in mycobacteria. Towards that, we use Mycobacterium smegmatis (Msm), an avirulent soil mycobacterium as the model system. We first describe the generation and enrichment of native EVs of Msm. Then, we describe the design and construction of recombinant mEVs that contain either mCherry, a red fluorescent reporter protein, or EsxA (Esat-6), a prominent immunogen of Mycobacterium tuberculosis. We achieve this by separately fusing mCherry and EsxA N-termini with the C-terminus of a small Msm protein Cfp-29. Cfp-29 is one of the few abundantly present proteins of MsmEVs. The protocol to generate and enrich recombinant mEVs from Msm remains identical to the generation and enrichment of native EVs of Msm.

Association of COVID-19 with Comorbidities: An Update.

Coronavirus disease (COVID-19) is caused by severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) which was identified in Wuhan, China in December 2019 and jeopardized human lives. It spreads at an unprecedented rate worldwide, with serious and still-unfolding health conditions and economic ramifications. Based on the clinical investigations, the severity of COVID-19 appears to be highly variable, ranging from mild to severe infections including the death of an infected individual. To add to this, patients with comorbid conditions such as age or concomitant illnesses are significant predictors of the disease's severity and progression. SARS-CoV-2 enters inside the host cells through ACE2 (angiotensin converting enzyme2) receptor expression; therefore, comorbidities associated with higher ACE2 expression may enhance the virus entry and the severity of COVID-19 infection. It has already been recognized that age-related comorbidities such as Parkinson's disease, cancer, diabetes, and cardiovascular diseases may lead to life-threatening illnesses in COVID-19-infected patients. COVID-19 infection results in the excessive release of cytokines, called "cytokine storm", which causes the worsening of comorbid disease conditions. Different mechanisms of COVID-19 infections leading to intensive care unit (ICU) admissions or deaths have been hypothesized. This review provides insights into the relationship between various comorbidities and COVID-19 infection. We further discuss the potential pathophysiological correlation between COVID-19 disease and comorbidities with the medical interventions for comorbid patients. Toward the end, different therapeutic options have been discussed for COVID-19-infected comorbid patients.

The Iron Response of Mycobacterium tuberculosis and Its Implications for Tuberculosis Pathogenesis and Novel Therapeutics.

Most pathogenic bacteria require iron for growth. However, this metal is not freely available in the mammalian host. Due to its poor solubility and propensity to catalyze the generation of reactive oxygen species, host iron is kept in solution bound to specialized iron binding proteins. Access to iron is an important factor in the outcome of bacterial infections; iron limitation frequently induces virulence and drives pathogenic interactions with host cells. Here, we review the response of Mycobacterium tuberculosis to changes in iron availability, the relevance of this response to TB pathogenesis, and its potential for the design of new therapeutic interventions.

Living Donor Liver Transplantation in a Cohort of Recipients With Left Ventricular Systolic Dysfunction.

Background: Data on feasibility, management, and outcomes of liver transplantation (LT) in patients with pre-existing left ventricular systolic dysfunction (LVSD), severe coronary artery disease (CAD) or cirrhotic cardiomyopathy (CCM) is scarce. Methods: We reviewed outcomes of living donor liver transplantation (LDLT) in recipients with LVSD (ejection fraction [EF] < 50%) from our series of 1946 LDLT's performed between July 2010 and July 2018. Results: LVSD was detected in 12 male patients with a mean age, BMI and MELD of 52 ± 9 years, 25 ± 5 kg/m2, and 19 ± 4 respectively. Out of these, 6 patients had CAD (2 with previous coronary artery bypass graft, 1 following recent percutaneous transluminal coronary angioplasty, 2 post myocardial infarction, 1 noncritical CAD), and 6 had CCM. The EF ranged from 25% to 45%. Ethanol was the predominant underlying etiology for cirrhosis (50%). During LDLT, 2 patients developed ventricular ectopic rhythm and were managed successfully with intravenous lidocaine. Stress cardiomyopathy manifested in 3 patients post operatively with decreased EF, of which 2 improved, while 1 needed IABP support and succumbed to multiorgan failure on 8th postoperative day (POD). Another patient died on POD30 due to septic shock. Both these patients had higher MELD scores (actual MELD), extremes of BMI (17.3and 35.8 kg/m2) and were diabetic. There were no long-term cardiac deaths. The 1-year, and 5-year survival were 75%, and 66%, respectively. Conclusion: Among potential LT recipients with LVSD, those with stable CAD and good performance status, and well optimized CCM patients may be considered for LDLT after careful risk stratification in experienced centers.

One for Everyone: A Study of User Satisfaction Among Health-Care Providers Regarding Extended Use of N95 Masks During the COVID-19 Pandemic.

OBJECTIVE: This study was conducted to assess the feasibility of extended use of N95 masks in our hospital during the coronavirus disease 2019 (COVID-19) pandemic. We also studied the use pattern, user satisfaction, and issues faced during extended use of the mask. METHODS: This cross-sectional study was conducted among health-care providers in a large tertiary care teaching hospital in northern India from April 1 to May 31, 2020. A list was prepared from the institute's register, and participants were chosen by random sampling. The data collected from the physical forms were transferred to excel sheets. RESULTS: A total of 1121 responses were received. The most common problem stated with reuse of N95 masks was loss of fit followed by damage to the slings, highlighted by 44.6% and 44.4% of the participants, respectively. A total of 476 (42.5%) participants responded that they would prefer "cup-shaped N95 mask with respirator". The median scores regarding the satisfaction with the quality of masks and their fit was also 4 each. CONCLUSIONS: It was concluded that the extended use of N95 masks was acceptable, with more than 96% of the participants using these masks.

Intranasal Exposure to Low-Dose Rotenone Induced Alpha-Synuclein Accumulation and Parkinson's Like Symptoms Without Loss of Dopaminergic Neurons.

Epidemiologically Parkinson's disease (PD) is associated with chronic ingestion or inhalation of environmental toxins leading to the development of motor symptoms. Though neurotoxin-based animal models played a major role in understanding diverse pathogenesis, they failed to identify the risk assessment due to uncommon route of toxin exposure. Towards this, the available neurotoxin-based intranasal (i.n.) PD models targeting olfactory bulb (OB) have demonstrated the dopaminergic (DAergic) neurodegeneration in both OB and substantia nigra (SN). Despite that, the studies detecting the alpha-synuclein (α-syn) accumulation in OB and its progression to other brain regions due to inhalation of environmental toxins are still lacking. Herein, we developed oil in water microemulsion of rotenone administered intranasally to the mice at a dose which is not detectable in blood, brain, and olfactory bulb by LCMS method. Our data reveals that 9 weeks of rotenone exposure did not induce olfactory and motor dysfunction. Conversely, after 16 weeks of washout period, rotenone treated mice showed both olfactory and motor impairment, along with α-syn accumulation in the OB and striatum without glial cell activation and loss of dopaminergic neurons. The results depict the progressive nature of the developed model and highlight the role of α-syn in PD like pathology or symptoms. Together, our findings suggest the adverse consequences of early exposure to the environmental toxins on the olfactory system for a shorter period with relevance to the development of synucleinopathy or Parkinson's disease in its later stage.