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1.
Opt Lett ; 49(1): 17-20, 2024 Jan 01.
Article in English | MEDLINE | ID: mdl-38134141

ABSTRACT

We present the design and development of an all-solid-state (fluid/refrigerant-free) 100 W scale blue-laser system and show its applications in precision copper works. We combine powerful laser-diode arrays with Peltier chips on a compact laser head to achieve stable thermal and optical performance. Good agreement between the thermal simulation of the 3D laser head and experiments validates stable thermal performance. The laser system emits 40-100 W continuous wave at λ = 452.2 ± 2.5 nm with 98% power stability and ∼24% wall-plug efficiency inside a portable enclosure. This is the first, to the best of our knowledge, all-solid-state air-cooled laser with a 100 W class output. We achieved kW/cm2 intensity level on an mm-size focus with this source and demonstrated cutting, bending, and soldering copper on a battery pack. Furthermore, the copper-solder joints have nanoscale adhesion without cracks. Additionally, we unveil that 0.5-4 kW/cm2 intensity laser annealing scan makes copper strips mechanically resilient to withstand extreme loading cycles without nanoscale cracks.

2.
J Biol Chem ; 298(3): 101719, 2022 03.
Article in English | MEDLINE | ID: mdl-35151690

ABSTRACT

The mitochondrial protein LonP1 is an ATP-dependent protease that mitigates cell stress and calibrates mitochondrial metabolism and energetics. Biallelic mutations in the LONP1 gene are known to cause a broad spectrum of diseases, and LonP1 dysregulation is also implicated in cancer and age-related disorders. Despite the importance of LonP1 in health and disease, specific inhibitors of this protease are unknown. Here, we demonstrate that 2-cyano-3,12-dioxooleana-1,9(11)-dien-28-oic acid (CDDO) and its -methyl and -imidazole derivatives reversibly inhibit LonP1 by a noncompetitive mechanism, blocking ATP-hydrolysis and thus proteolysis. By contrast, we found that CDDO-anhydride inhibits the LonP1 ATPase competitively. Docking of CDDO derivatives in the cryo-EM structure of LonP1 shows these compounds bind a hydrophobic pocket adjacent to the ATP-binding site. The binding site of CDDO derivatives was validated by amino acid substitutions that increased LonP1 inhibition and also by a pathogenic mutation that causes cerebral, ocular, dental, auricular and skeletal (CODAS) syndrome, which ablated inhibition. CDDO failed to inhibit the ATPase activity of the purified 26S proteasome, which like LonP1 belongs to the AAA+ superfamily of ATPases Associated with diverse cellular Activities, suggesting that CDDO shows selectivity within this family of ATPases. Furthermore, we show that noncytotoxic concentrations of CDDO derivatives in cultured cells inhibited LonP1, but not the 26S proteasome. Taken together, these findings provide insights for future development of LonP1-specific inhibitors with chemotherapeutic potential.


Subject(s)
ATP-Dependent Proteases , Adenosine Triphosphate , Mitochondria , Mitochondrial Proteins , Oleanolic Acid/analogs & derivatives , Adenosine Triphosphate/metabolism , Endopeptidases/metabolism , Hydrolysis/drug effects , Mitochondria/drug effects , Mitochondria/enzymology , Mitochondria/metabolism , Mitochondrial Proteins/antagonists & inhibitors , Oleanolic Acid/pharmacology
3.
Article in English | MEDLINE | ID: mdl-38050469

ABSTRACT

Given the increased health dangers of tobacco use, particularly in developing countries, smoking cessation intervention is crucially important. The aim of this study is to determine and assess the effectiveness of a comprehensive smoking cessation intervention program, incorporating behavior modification, counseling, and pharmacologic treatments, in the context of the Indian scenario. The process of initiating smoking or tobacco cessation begins with the evaluation of the distinct stages that smokers undergo as part of their journey toward behavioral change. There are five different levels of preparation for quitting smoking, i.e., i) not prepared (pre-contemplation); ii) unsure (contemplation); iii) prepared (preparation); iv) action; and v) maintenance. Behavior modification and counseling are essential. The "5 A's"-based intervention uses ask, advise, assess, assist, and arrange as part of its strategy. First-line treatments such as nicotine replacement therapy, bupropion, and varenicline, as well as second-line treatments such as clonidine, cytisine, and nortriptyline, are the foundation of pharmacologic care. Every healthcare professional has a duty to help smokers stop using tobacco, and the intervention should be both therapeutic and diagnostic. Combining behavioral and social support yields the best results, along with pharmacotherapy whenever needed.

4.
RNA ; 26(11): 1667-1679, 2020 11.
Article in English | MEDLINE | ID: mdl-32732393

ABSTRACT

Nucleic acid aptamers can be chemically modified to enhance function, but modifying previously selected aptamers can have nontrivial structural and functional consequences. We present a reselection strategy to evaluate the impact of several modifications on preexisting aptamer pools. RNA aptamer libraries with affinity to HIV-1 reverse transcriptase (RT) were retranscribed with 2'-F, 2'-OMe, or 2'-NH2 pyrimidines and subjected to three additional selection cycles. RT inhibition was observed for representative aptamers from several structural families identified by high-throughput sequencing when transcribed with their corresponding modifications. Thus, reselection identified specialized subsets of aptamers that tolerated chemical modifications from unmodified preenriched libraries. Inhibition was the strongest with the 2'-F-pyrimidine (2'-FY) RNAs, as compared to inhibition by the 2'-OMeY and 2'-NH2Y RNAs. Unexpectedly, a diverse panel of retroviral RTs were strongly inhibited by all 2'-FY-modified transcripts, including sequences that do not inhibit those RTs as unmodified RNA. The magnitude of promiscuous RT inhibition was proportional to mole fraction 2'-FY in the transcript. RT binding affinity by 2'-FY transcripts was more sensitive to salt concentration than binding by unmodified transcripts, indicating that interaction with retroviral RTs is more ionic in character for 2'-FY RNA than for unmodified 2'-OH RNA. These surprising features of 2'-FY-modified RNA may have general implications for applied aptamer technologies.


Subject(s)
Aptamers, Nucleotide/chemical synthesis , HIV Reverse Transcriptase/antagonists & inhibitors , HIV-1/enzymology , Pyridines/chemistry , Reverse Transcriptase Inhibitors/chemical synthesis , Aptamers, Nucleotide/chemistry , Aptamers, Nucleotide/pharmacology , Drug Evaluation, Preclinical , Gene Library , HIV-1/drug effects , High-Throughput Nucleotide Sequencing , Humans , Nucleic Acid Conformation , Reverse Transcriptase Inhibitors/chemistry , Reverse Transcriptase Inhibitors/pharmacology , SELEX Aptamer Technique
5.
J Virol ; 95(24): e0143721, 2021 11 23.
Article in English | MEDLINE | ID: mdl-34550770

ABSTRACT

The outbreak of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is responsible for the coronavirus disease 19 (COVID-19) pandemic. Despite unprecedented research and developmental efforts, SARS-CoV-2-specific antivirals are still unavailable for the treatment of COVID-19. In most instances, SARS-CoV-2 infection initiates with the binding of Spike glycoprotein to the host cell ACE2 receptor. Utilizing the crystal structure of the ACE2/Spike receptor-binding domain (S-RBD) complex (PDB file 6M0J) in a computer-aided drug design approach, we identified and validated five potential inhibitors of S-RBD and ACE-2 interaction. Two of the five compounds, MU-UNMC-1 and MU-UNMC-2, blocked the entry of pseudovirus particles expressing SARS-CoV-2 Spike glycoprotein. In live SARS-CoV-2 infection assays, both compounds showed antiviral activity with IC50 values in the micromolar range (MU-UNMC-1: IC50 = 0.67 µM and MU-UNMC-2: IC50 = 1.72 µM) in human bronchial epithelial cells. Furthermore, MU-UNMC-1 and MU-UNMC-2 effectively blocked the replication of rapidly transmitting variants of concern: South African variant B.1.351 (IC50 = 9.27 and 3.00 µM) and Scotland variant B.1.222 (IC50 = 2.64 and 1.39 µM), respectively. Following these assays, we conducted "induced-fit (flexible) docking" to understand the binding mode of MU-UNMC-1/MU-UNMC-2 at the S-RBD/ACE2 interface. Our data showed that mutation N501Y (present in B.1.351 variant) alters the binding mode of MU-UNMC-2 such that it is partially exposed to the solvent and has reduced polar contacts. Finally, MU-UNMC-2 displayed high synergy with remdesivir, the only approved drug for treating hospitalized COVID-19 patients. IMPORTANCE The ongoing coronavirus infectious disease 2019 (COVID-19) pandemic is caused by a novel coronavirus named severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). More than 207 million people have been infected globally, and 4.3 million have died due to this viral outbreak. While a few vaccines have been deployed, a SARS-CoV-2-specific antiviral for the treatment of COVID-19 is yet to be approved. As the interaction of SARS-CoV-2 Spike protein with ACE2 is critical for cellular entry, using a combination of a computer-aided drug design (CADD) approach and cell-based in vitro assays, we report the identification of five potential SARS-CoV-2 entry inhibitors. Out of the five, two compounds (MU-UNMC-1 and MU-UNMC-2) have antiviral activity against ancestral SARS-CoV-2 and emerging variants from South Africa and Scotland. Furthermore, MU-UNMC-2 acts synergistically with remdesivir (RDV), suggesting that RDV and MU-UNMC-2 can be developed as a combination therapy to treat COVID-19 patients.


Subject(s)
COVID-19 Drug Treatment , COVID-19/virology , SARS-CoV-2/drug effects , Adenosine Monophosphate/analogs & derivatives , Adenosine Monophosphate/pharmacology , Alanine/analogs & derivatives , Alanine/pharmacology , Angiotensin-Converting Enzyme 2/metabolism , Animals , Antiviral Agents/pharmacology , Chemistry, Pharmaceutical/methods , Chlorocebus aethiops , Computer Simulation , Drug Design , HEK293 Cells , Humans , Inhibitory Concentration 50 , Models, Molecular , Molecular Dynamics Simulation , Mutation , Protein Binding , Protein Domains , Protein Interaction Domains and Motifs , Spike Glycoprotein, Coronavirus , Vero Cells
6.
J Virol ; 95(18): e0047921, 2021 08 25.
Article in English | MEDLINE | ID: mdl-34232744

ABSTRACT

HIV-1 elite controllers (EC) are a rare group among HIV-1-infected individuals who can naturally control viral replication for a prolonged period. Due to their heterogeneous nature, no universal mechanism could be attributed to the EC status; instead, several host and viral factors have been discussed as playing a role. In this study, we investigated the fecal metabolome and microbiome in a Swedish cohort of EC (n = 14), treatment-naive viremic progressors (VP; n = 16), and HIV-negative individuals (HC; n = 12). Fecal untargeted metabolomics was performed by four ultra-high-performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS). Molecular docking and biochemical microscale thermophoresis (MST) were used to describe the peptide-metabolite interactions. Single-cycle infectivity assays were performed in TZM-Bl cell lines using CCR5- and CXCR4-tropic HIV-1 strains. The microbiome analysis was performed using 16S rRNA sequencing. Th effects of metabolites on bacterial species viability were determined using several clinical isolates. We observed an enrichment of dipeptides in EC compared to VP and HC (adjusted P < 0.05). In silico analysis by molecular docking, in vitro biochemical assays, and ex vivo infection assays identified anti-HIV-1 properties for two dipeptides (WG and VQ) that could bind to the HIV-1 gp120, of which WG was more potent. The microbiome analysis identified enrichment of the genus Prevotella in EC, and these dipeptides supported bacterial growth of the genus Prevotella in vitro. The enrichments of the dipeptides and higher abundance of Prevotella have a distinct mechanism of elite control status in HIV-1 infection that influences host metabolism. IMPORTANCE HIV-1 elite controllers (EC) are a rare group among HIV-1-infected individuals who can naturally control viral replication for a prolonged period. Due to their heterogeneous nature, no universal mechanism could be attributed to the EC status; instead, several host and viral factors have been discussed as playing a role. In this study, we investigated the fecal metabolome and microbiome in a Swedish cohort of EC, treatment-naive viremic progressors (VP), and HIV-negative individuals (HC). We observed an enrichment of dipeptides in EC compared to the other two study groups. In silico and in vitro analyses identified anti-HIV-1 properties for two dipeptides that could bind to the HIV-1 gp120 and act as an HIV-1 antagonist. Furthermore, these dipeptides supported bacterial growth of the genus Prevotella in vitro that was enriched in EC, which influences host metabolism. Thus, increased levels of both dipeptides and Prevotella could provide beneficial effects for EC.


Subject(s)
Bacteroidaceae Infections/microbiology , Dipeptides/pharmacology , Feces/microbiology , HIV Infections/prevention & control , HIV-1/physiology , Metabolome , Prevotella/pathogenicity , Adult , Bacteroidaceae Infections/drug therapy , CD4-Positive T-Lymphocytes/drug effects , CD4-Positive T-Lymphocytes/virology , Case-Control Studies , Cohort Studies , Feces/chemistry , Female , Gene Expression Profiling , HIV Infections/virology , HIV-1/drug effects , Humans , Male , Middle Aged , Molecular Docking Simulation , Phenotype , Virus Replication
7.
J Autoimmun ; 126: 102779, 2022 01.
Article in English | MEDLINE | ID: mdl-34915422

ABSTRACT

Severe Acute Respiratory Coronavirus (SARS-CoV-2) has been emerging in the form of different variants since its first emergence in early December 2019. A new Variant of Concern (VOC) named the Omicron variant (B.1.1.529) was reported recently. This variant has a large number of mutations in the S protein. To date, there exists a limited information on the Omicron variant. Here we present the analyses of mutation distribution, the evolutionary relationship of Omicron with previous variants, and probable structural impact of mutations on antibody binding. Our analyses show the presence of 46 high prevalence mutations specific to Omicron. Twenty-three of these are localized within the spike (S) protein and the rest localized to the other 3 structural proteins of the virus, the envelope (E), membrane (M), and nucleocapsid (N). Phylogenetic analysis showed that the Omicron is closely related to the Gamma (P.1) variant. The structural analyses showed that several mutations are localized to the region of the S protein that is the major target of antibodies, suggesting that the mutations in the Omicron variant may affect the binding affinities of antibodies to the S protein.


Subject(s)
Antibodies, Viral/immunology , COVID-19/virology , SARS-CoV-2/genetics , Binding Sites , COVID-19/immunology , Humans , Mutation , Phylogeny , Protein Structure, Tertiary , Spike Glycoprotein, Coronavirus/genetics
8.
J Autoimmun ; 133: 102928, 2022 12.
Article in English | MEDLINE | ID: mdl-36252459

ABSTRACT

Attributes contributing to the current monkeypox virus (MPXV) outbreak remain unknown. It has been established that mutations in viral proteins may alter phenotype and pathogenicity. To assess if mutations in the MPXV DNA replication complex (RC) contribute to the outbreak, we conducted a temporal analysis of available MPXV sequences to identify mutations, generated a DNA replication complex (RC) using structures of related viral and eukaryotic proteins, and structure prediction method AlphaFold. Ten mutations within the RC were identified and mapped onto the RC to infer role of mutations. Two mutations in F8L (RC catalytic subunit), and two in G9R (a processivity factor) were ∼100% prevalent in the 2022 sequences. F8L mutation L108F emerged in 2022, whereas W411L emerged in 2018, and persisted in 2022. L108 is topologically located to enhance DNA binding affinity of F8L. Therefore, mutation L108F can change the fidelity, sensitivity to nucleoside inhibitors, and processivity of F8L. Surface exposed W411L likely affects the binding of regulatory factor(s). G9R mutations S30L and D88 N in G9R emerged in 2022, and may impact the interaction of G9R with E4R (uracil DNA glycosylase). The remaining six mutations that appeared in 2001, reverted to the first (1965 Rotterdam) isolate. Two nucleoside inhibitors brincidofovir and cidofovir have been approved for MPXV treatment. Cidofovir resistance in vaccinia virus is achieved by A314T and A684V mutations. Both A314 and A684 are conserved in MPXV. Therefore, resistance to these drugs in MPXV may arise through similar mechanisms.


Subject(s)
Nucleosides , Virus Replication , Mutation , Virus Replication/genetics
9.
BMC Microbiol ; 22(1): 236, 2022 10 03.
Article in English | MEDLINE | ID: mdl-36192704

ABSTRACT

BACKGROUND: The emergence of multidrug-resistant tuberculosis (MDR-TB) has complicated the situation due to the decline in potency of second-line anti-tubercular drugs. This limits the treatment option for extensively drug-resistant tuberculosis (XDR-TB). The aim of this study was to determine and compare the minimum inhibitory concentration (MIC) by agar dilution and resazurin microtiter assay (REMA) along with the detection of mutations against linezolid and clofazimine in confirmed XDR-TB clinical isolates. RESULTS: A total of 169 isolates were found positive for Mycobacterium tuberculosis complex (MTBC). The MIC was determined by agar dilution and REMA methods. The isolates which showed non-susceptibility were further subjected to mutation detection by targeting rplC gene (linezolid) and Rv0678 gene (clofazimine). The MIC for linezolid ranged from 0.125 µg/ml to > 2 µg/ml and for clofazimine from 0.25 µg/ml to > 4 µg/ml. The MIC50 and MIC90 for linezolid were 0.5 µg/ml and 1 µg/ml respectively while for clofazimine both were 1 µg/ml. The essential and categorical agreement for linezolid was 97.63% and 95.26% and for clofazimine, both were 100%. The sequencing result of the rplC gene revealed a point mutation at position 460 bp, where thymine (T) was substituted for cytosine (C) while seven mutations were noted between 46 to 220 bp in Rv0678 gene. CONCLUSION: REMA method has been found to be more suitable in comparison to the agar dilution method due to lesser turnaround time. Mutations in rplC and Rv0678 genes were reasons for drug resistance against linezolid and clofazimine respectively.


Subject(s)
Extensively Drug-Resistant Tuberculosis , Mycobacterium tuberculosis , Tuberculosis, Multidrug-Resistant , Agar , Antitubercular Agents/pharmacology , Clofazimine/pharmacology , Clofazimine/therapeutic use , Cytosine/therapeutic use , Drug Resistance, Multiple, Bacterial/genetics , Extensively Drug-Resistant Tuberculosis/drug therapy , Extensively Drug-Resistant Tuberculosis/microbiology , Humans , Linezolid/pharmacology , Linezolid/therapeutic use , Microbial Sensitivity Tests , Mutation , Thymine/therapeutic use , Tuberculosis, Multidrug-Resistant/microbiology
10.
Opt Express ; 30(25): 45020-45030, 2022 Dec 05.
Article in English | MEDLINE | ID: mdl-36522913

ABSTRACT

Tunable attosecond pulses are necessary for various attosecond resolved spectroscopic applications, which can potentially be obtained through the tuning of high harmonic generation. Here we show theoretically, using the time-dependent Schrödinger equation and strong field approximation, a continuously tunable spectral shift of high-order harmonics by exploiting the interaction of two delayed identical infrared (IR) pulses within the single-atom response. The tuning spans more than twice the driving frequency (∼2ω) range, for several near-cutoff harmonics, with respect to only one control parameter: the change in delay between the two IR pulses. We show that two distinct mechanisms contribute to the spectral shift of the harmonic spectra. The dominant part of the spectral shift of the harmonics is due to the modulation of the central frequency of the composite IR-IR pulse with respect to delay. The second contribution comes from the non-adiabatic phase-shift of the recolliding electron wavepacket due to the change in amplitude of the subcycle electric field within the double pulse envelope. For optical few-cycle pulses this scheme can produce tunable attosecond pulse trains (APT), and in the single-cycle regime the same can be used for tuning isolated attosecond pulses (IAP). We quantify the dependence of tuning range and tuning rate on the laser pulse duration. We envision that the proposed scheme can be easily implemented with compact in-line setups for generating frequency tunable APT/IAP.

11.
Opt Lett ; 47(22): 5993-5996, 2022 Nov 15.
Article in English | MEDLINE | ID: mdl-37219155

ABSTRACT

We show a noise self-canceling real-time picometer scale interferometer by exploiting the unique spiral phase structure of twisted light. We use a single cylindrical interference-lens to implement the twisted interferometer and perform simultaneous measurement on N phase-orthogonal single-pixel intensity pairs chosen on the petal of the daisy-flower-like interference pattern. A cancellation of various noises by three orders of magnitude was achieved in our setup compared with a conventional single-pixel detection, enabling a sub-100 picometer resolution in measuring a non-repetitive intracavity dynamic event in real-time. Furthermore, the noise cancellation capability of the twisted interferometer scales up statistically for higher radial and azimuthal quantum numbers of the twisted light. The proposed scheme could find applications in precision metrology and in developing analogous ideas for twisted acoustic beam, electron beams, and matter waves.

12.
Int J Mol Sci ; 23(3)2022 Jan 20.
Article in English | MEDLINE | ID: mdl-35163023

ABSTRACT

Smaller oligomeric chaperones of α-crystallins (αA- and αB-) have received increasing attention due to their improved therapeutic potential in preventing protein aggregating diseases. Our previous study suggested that deleting 54-61 residues from the N-terminal domain (NTD) of αB-crystallin (αBΔ54-61) decreases the oligomer size and increases the chaperone function. Several studies have also suggested that NTD plays a significant role in protein oligomerization and chaperone function. The current study was undertaken to assess the effect of deleting conserved 21-28 residues from the activated αBΔ54-61 (to get αBΔ21-28, Δ54-61) on the structure-function of recombinant αBΔ21-28, Δ54-61. The αBΔ21-28, Δ54-61 mutant shows an 80% reduction in oligomer size and 3- to 25-fold increases in chaperone activity against model substrates when compared to αB-WT. Additionally, the αB∆21-28, ∆54-61 was found to prevent ß-amyloid (Aß1-42) fibril formation in vitro and suppressed Aß1-42-induced cytotoxicity in ARPE-19 cells in a more effective manner than seen with αB-WT or αB∆54-61. Cytotoxicity and reactive oxygen species (ROS) detection studies with sodium iodate (SI) showed that the double mutant protein has higher anti-apoptotic and anti-oxidative activities than the wild-type or αB∆54-61 in oxidatively stressed cells. Our study shows that the residues 21-28 and 54-61 in αB-crystallin contribute to the oligomerization and modulate chaperone function. The deletion of conserved 21-28 residues further potentiates the activated αBΔ54-61. We propose that increased substrate affinity, altered subunit structure, and assembly leading to smaller oligomers could be the causative factors for the increased chaperone activity of αBΔ21-28, Δ54-61.


Subject(s)
Antioxidants/pharmacology , Molecular Chaperones/pharmacology , Mutation , Oxidative Stress , Retinal Pigment Epithelium/drug effects , alpha-Crystallin B Chain/pharmacology , Amino Acid Sequence , Apoptosis , Cells, Cultured , Humans , Mutagenesis, Site-Directed , Retinal Pigment Epithelium/metabolism , Retinal Pigment Epithelium/pathology , alpha-Crystallin B Chain/chemistry , alpha-Crystallin B Chain/genetics
13.
Int J Mol Sci ; 23(10)2022 May 16.
Article in English | MEDLINE | ID: mdl-35628343

ABSTRACT

BA.2, a sublineage of Omicron BA.1, is now prominent in many parts of the world. Early reports have indicated that BA.2 is more infectious than BA.1. To gain insight into BA.2 mutation profile and the resulting impact of mutations on interactions with receptor and/or monoclonal antibodies, we analyzed available sequences, structures of Spike/receptor and Spike/antibody complexes, and conducted molecular dynamics simulations. The results showed that BA.2 had 50 high-prevalent mutations, compared to 48 in BA.1. Additionally, 17 BA.1 mutations were not present in BA.2. Instead, BA.2 had 19 unique mutations and a signature Delta variant mutation (G142D). The BA.2 had 28 signature mutations in Spike, compared to 30 in BA.1. This was due to two revertant mutations, S446G and S496G, in the receptor-binding domain (RBD), making BA.2 somewhat similar to Wuhan-Hu-1 (WT), which had G446 and G496. The molecular dynamics simulations showed that the RBD consisting of G446/G496 was more stable than S446/S496 containing RBD. Thus, our analyses suggested that BA.2 evolved with novel mutations (i) to maintain receptor binding similar to WT, (ii) evade the antibody binding greater than BA.1, and (iii) acquire mutation of the Delta variant that may be associated with the high infectivity.


Subject(s)
Antibodies, Monoclonal , Molecular Dynamics Simulation , Mutation
14.
J Assoc Physicians India ; 70(4): 11-12, 2022 Apr.
Article in English | MEDLINE | ID: mdl-35443535

ABSTRACT

Chronic liver disease (CLD) patients develop portal hypertension which lead to complications like splenomegaly, ascites and esophageal varices. Portal hypertension is defined as hepatic venous pressure gradient more than 5mmHg, being invasive it is difficult to measure. Some studies show that increased portal vein diameter (PVD) on ultrasonography correlate with oesophageal varices and can indicate portal hypertension. Studies correlating PVD with other complications of portal hypertension like ascites and spleen size are lacking. Aim of this study was to correlate portal vein diameter with ascites, spleen size, thrombocytopenia and prognostic markers like Child-Turcotte Pugh (CTP) score and Model for End stage Liver Disease (MELD) score in Chronic liver disease patients. MATERIAL: This was a cross-sectional observational study of patients with Chronic liver disease conducted at tertiary care teaching hospital. All patient underwent clinical history, examination, blood testing and ultrasonography. Data collected was analysed by using statistical tests. OBSERVATION: Out of 97 CLD patients taken in study, the mean age of patients was 47.39 ± 12.64 year and majority were male (75.3%). Most common etiological factor was alcohol (in 53.7%). On clinical examination, 55.7% patients had pallor, 54.6% had icterus. Chest radiograph shows pleural effusion in 14.4% patients. Mean portal vein diameter was found to be 12.31 ± 2.71mm. Correlation coefficient of portal vein diameter with spleen size was 0.3 with p value of 0.004 suggesting a positive correlation. Parameters like thrombocytopenia, CTP score and MELD score correlation coefficient was -0.2(p-value: 0.066), 0.1(p value: 0.463) and 0.0(p-value: 0.725) respectively. The mean of PVD(mm) in ascites group was 12.43 and non ascites group was 11.92. Strength of association was 0.08 (Point Biserial correlation) indicating no association. CONCLUSION: Portal vein diameter had positive correlation with spleen size which is statistically significant in our study. No significant correlation was observed between PVD with ascites, thrombocytopenia, CTP score and MELD score.


Subject(s)
End Stage Liver Disease , Esophageal and Gastric Varices , Hypertension, Portal , Thrombocytopenia , Female , Humans , Male , Ascites/diagnostic imaging , Ascites/etiology , Cross-Sectional Studies , End Stage Liver Disease/complications , Esophageal and Gastric Varices/complications , Esophageal and Gastric Varices/etiology , Hypertension, Portal/complications , Hypertension, Portal/diagnostic imaging , Liver Cirrhosis/complications , Portal Vein/diagnostic imaging , Severity of Illness Index , Thrombocytopenia/complications
15.
J Autoimmun ; 124: 102715, 2021 11.
Article in English | MEDLINE | ID: mdl-34399188

ABSTRACT

Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) has been rapidly evolving in the form of new variants. At least eleven known variants have been reported. The objective of this study was to delineate the differences in the mutational profile of Delta and Delta Plus variants. High-quality sequences (n = 1756) of Delta (B.1.617.2) and Delta Plus (AY.1 or B.1.617.2.1) variants were used to determine the prevalence of mutations (≥20 %) in the entire SARS-CoV-2 genome, their co-existence, and change in prevalence over a period of time. Structural analysis was conducted to get insights into the impact of mutations on antibody binding. A Sankey diagram was generated using phylogenetic analysis coupled with sequence-acquisition dates to infer the migration of the Delta Plus variant and its presence in the United States. The Delta Plus variant had a significant number of high-prevalence mutations (≥20 %) than in the Delta variant. Signature mutations in Spike (G142D, A222V, and T95I) existed at a more significant percentage in the Delta Plus variant than the Delta variant. Three mutations in Spike (K417N, V70F, and W258L) were exclusively present in the Delta Plus variant. A new mutation was identified in ORF1a (A1146T), which was only present in the Delta Plus variant with ~58 % prevalence. Furthermore, five key mutations (T95I, A222V, G142D, R158G, and K417N) were significantly more prevalent in the Delta Plus than in the Delta variant. Structural analyses revealed that mutations alter the sidechain conformation to weaken the interactions with antibodies. Delta Plus, which first emerged in India, reached the United States through England and Japan, followed by its spread to more than 20 the United States. Based on the results presented here, it is clear that the Delta and Delta Plus variants have unique mutation profiles, and the Delta Plus variant is not just a simple addition of K417N to the Delta variant. Highly correlated mutations may have emerged to keep the structural integrity of the virus.


Subject(s)
COVID-19/genetics , Evolution, Molecular , Mutation, Missense , Phylogeny , SARS-CoV-2/genetics , Amino Acid Substitution , COVID-19/epidemiology , COVID-19/transmission , Humans , Prevalence , SARS-CoV-2/metabolism
16.
Ann Clin Microbiol Antimicrob ; 20(1): 56, 2021 Aug 26.
Article in English | MEDLINE | ID: mdl-34446022

ABSTRACT

BACKGROUND: According to World Health Organization (WHO), drug-resistant tuberculosis (DR-TB) is a major contributor to antimicrobial resistance globally and continues to be a public health threat. Annually, about half a million people fall ill with DR-TB globally. The gradual increase in resistance to fluoroquinolones (FQs) and second-line injectable drugs (SLIDs), poses a serious threat to effective TB control and adequate patient management. Therefore, WHO suggests the use of GenoType MTBDRsl v.2.0 assay for detection of multiple mutations associated with FQs and SLIDs. Hence, the study was conducted to determine the prevalence of resistance to FQs and SLIDs by comparing direct GenoType MTBDRsl v.2.0 assay with phenotypic drug susceptibility testing (DST). METHODS: The study was conducted on 1320 smear positive sputum samples from a total of 2536 RR-TB, confirmed by GeneXpert MTB/RIF. The smear positive specimens were decontaminated, and DNA extraction was performed. Furthermore, the extracted DNA was used for GenoType MTBDRsl v.2.0 assay. While 20% of the decontaminated specimens were inoculated in Mycobacterium growth indicator tube (MGIT) for drug susceptibility testing (DST). RESULTS: Out of 1320 smear positive sputum samples, 1178 were identified as Mycobacterium tuberculosis complex (MTBC) and remaining were negative by GenoType MTBDRsl v.2.0 assay. Of the 1178 MTBC positive, 26.6% were sensitive to both FQs and SLIDs, whereas 57.3% were only FQs resistant and 15.9% were resistant to both FQs and SLIDs. Further DST of 225 isolates by liquid culture showed that 17% were sensitive to both FQs and SLIDs, 61.3% were only FQs resistant and 21.3% were resistant to both. The specificity for FQs and SLIDs was 92.31% and 100% whereas sensitivity was 100% respectively by GenoType MTBDRsl v.2.0 assay in direct sputum samples. CONCLUSIONS: Our study clearly suggests that GenoType MTBDRsl v.2.0 assay is a reliable test for the rapid detection of resistance to second-line drugs after confirmation by GeneXpert MTB/RIF assay for RR-TB. Though, high rate FQ (ofloxacin) resistance was seen in our setting, moxifloxacin could be used as treatment option owing to very low resistance.


Subject(s)
Extensively Drug-Resistant Tuberculosis/diagnosis , Extensively Drug-Resistant Tuberculosis/drug therapy , Fluoroquinolones/pharmacology , Mycobacterium tuberculosis/genetics , Sputum/microbiology , Antitubercular Agents/pharmacology , Antitubercular Agents/therapeutic use , Genotype , Humans , India , Microbial Sensitivity Tests , Mycobacterium tuberculosis/isolation & purification
17.
Monaldi Arch Chest Dis ; 91(3)2021 May 11.
Article in English | MEDLINE | ID: mdl-33985325

ABSTRACT

Asthma is a heterogeneous disease with distinct phenotypes. Serum tIgE, SSIgE and SPT are the methods of evaluating allergen sensitization. The present study evaluates the exposure and sensitization to cockroach (Periplaneta americana) antigens in asthma patients in a metropolitan city of India. The study enrolled 200 consecutive bronchial asthma patients, diagnosed as per GINA guidelines. As per history of exposure to cockroaches, the patients are divided in two groups as exposed and non-exposed asthmatic. All the enrolled subjects underwent SPT against common aeroallergens including cockroach, spirometry and estimation of tIgE level and SSIgE against cockroach. Out of 200 asthma patients, a total of 114 (57%) asthmatic were found SPT positive against one of the common aeroallergens, of which 68 (34%) showed SPT sensitivity against cockroach. A total of 103 (51.5%) patients were found exposed to cockroaches. In the cockroach exposed group, the mean serum tIgE was found significantly higher than the non-exposed group (569.31±224.64 vs 479.29±237 IU/ml; p=0.007). The mean SSIgE against cockroach in exposed groups was found not significant than non-expose group (4.87±11.19 vs 4.11±8.39 KUA/L; p=0.589). The mean tIgE was also not significant in atopic compared to non-atopic asthmatic (553.25±218.12 IU/ml vs 489.1±251.16 IU/ml; p=0.056). The mean SSIgE against cockroach was 5.66±10.45 KUA/L for atopic and 2.96±8.98 KUA/L for non-atopic (p=0.054). The airway obstruction was almost the same in both groups.  Asthmatic patients who were exposed to cockroach and atopic had high tIgE, SSIgE levels and SPT positivity against cockroach antigen compared to non-exposed patients.


Subject(s)
Asthma , Cockroaches , Allergens , Animals , Asthma/epidemiology , Humans , Immunoglobulin E , Skin Tests
18.
Health Promot J Austr ; 32 Suppl 2: 301-307, 2021 Oct.
Article in English | MEDLINE | ID: mdl-32761937

ABSTRACT

ISSUE ADDRESSED: Obesity and non-communicable diseases (NCDs) are largely preventable by understanding the connection between socio-cultural knowledge, yet intervention effectiveness may hinder changes in lifestyles and behaviours in Indigenous health. This study performed to understand the social and cultural components, which contribute to obesity in rural areas of the Indigenous Fijian. METHODS: This study is a Community-Based Participatory Research (CBPR) project, which engaged community members from a rural iTaukei village in the Fiji Islands. Data collection was carried out through community consultation and semi-structured interviews. The data were analysed using descriptive thematic analysis. RESULTS: Food intake was associated with socio-cultural, economic, political and physical environmental factors. Participants reveal previous health promotion programs did not incorporate the cultural values, cultural competence beliefs and traditional ways of rural Indigenous Fijian community. CONCLUSION: The health care providers and policymakers need to be involved in recognising iTaukei community culture and appreciate traditional methods to promote equitable community participation in decision-making for health promotion. SO WHAT?: Community-wide lifestyle interventions, conceptual approaches based on communal perceptions of the problem at hand can also be the basis for future research on identifying socio-cultural factors, for example, the community and family support that can help shape behaviours.


Subject(s)
Obesity , Overweight , Eating , Fiji/epidemiology , Humans , Islands , Obesity/epidemiology , Overweight/epidemiology
19.
J Proteome Res ; 19(11): 4259-4274, 2020 11 06.
Article in English | MEDLINE | ID: mdl-33095583

ABSTRACT

Emerging and re-emerging infectious diseases due to RNA viruses cause major negative consequences for the quality of life, public health, and overall economic development. Most of the RNA viruses causing illnesses in humans are of zoonotic origin. Zoonotic viruses can directly be transferred from animals to humans through adaptation, followed by human-to-human transmission, such as in human immunodeficiency virus (HIV), severe acute respiratory syndrome coronavirus (SARS-CoV), Middle East respiratory syndrome coronavirus (MERS-CoV), and, more recently, SARS coronavirus 2 (SARS-CoV-2), or they can be transferred through insects or vectors, as in the case of Crimean-Congo hemorrhagic fever virus (CCHFV), Zika virus (ZIKV), and dengue virus (DENV). At the present, there are no vaccines or antiviral compounds against most of these viruses. Because proteins possess a vast array of functions in all known biological systems, proteomics-based strategies can provide important insights into the investigation of disease pathogenesis and the identification of promising antiviral drug targets during an epidemic or pandemic. Mass spectrometry technology has provided the capacity required for the precise identification and the sensitive and high-throughput analysis of proteins on a large scale and has contributed greatly to unravelling key protein-protein interactions, discovering signaling networks, and understanding disease mechanisms. In this Review, we present an account of quantitative proteomics and its application in some prominent recent examples of emerging and re-emerging RNA virus diseases like HIV-1, CCHFV, ZIKV, and DENV, with more detail with respect to coronaviruses (MERS-CoV and SARS-CoV) as well as the recent SARS-CoV-2 pandemic.


Subject(s)
Communicable Diseases, Emerging , Proteomics , RNA Virus Infections , Animals , COVID-19 , COVID-19 Testing , Clinical Laboratory Techniques , Communicable Diseases, Emerging/diagnosis , Communicable Diseases, Emerging/therapy , Communicable Diseases, Emerging/virology , Coronavirus Infections/diagnosis , Humans , Pandemics , Pneumonia, Viral , RNA Virus Infections/diagnosis , RNA Virus Infections/therapy , RNA Virus Infections/virology , RNA Viruses
20.
BMC Microbiol ; 20(1): 267, 2020 08 26.
Article in English | MEDLINE | ID: mdl-32847517

ABSTRACT

BACKGROUND: The burden of non-tuberculous mycobacterial (NTM) disease is increasing worldwide but still its diagnosis is delayed and it is mistaken as multidrug-resistant tuberculosis (MDR-TB).The present study was performed to develop a multiplex PCR assay for detection and identification of clinically most common NTM to the species level from pulmonary samples. RESULTS: Out of 50 isolates, 26 were identified as Mycobacterium kansasii (MK), 20 were identified as Mycobacterium abscessus (MA) and 4 were identified as Mycobacterium avium complex (MAC) through multiplex PCR and further confirmed by sequencing. CONCLUSION: Our study showed that multiplex PCR assay is a simple, convenient, and reliable technique for detection and differential identification of major NTM species.


Subject(s)
Multiplex Polymerase Chain Reaction/methods , Mycobacterium Infections, Nontuberculous/microbiology , Nontuberculous Mycobacteria/genetics , DNA Primers , Humans , Molecular Diagnostic Techniques/methods , Nontuberculous Mycobacteria/isolation & purification , Pneumonia
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