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1.
J Pediatr Surg ; 2024 Apr 22.
Article in English | MEDLINE | ID: mdl-38769032

ABSTRACT

INTRODUCTION: Abdominal tuberculosis presents in a variety of ways. Different testing modalities must be applied in addition to having a high clinical suspicion to diagnose and initiate therapy. Medications have a good response; however, morbidity has been seen following surgical management of complicated presentations like intestinal obstruction and perforation. There is a paucity of studies in the pediatric age group which evaluate response to the different treatment regimen and identify factors associated with poorer outcomes in children with abdominal tuberculosis. METHODS: Patient records of 75 children with abdominal tuberculosis at a single center were evaluated using a questionnaire, covering a 14-year period from 2007 to 2021. Demographic features, presenting signs and symptoms, investigations and treatment details were studied. In- person or telephonic follow-up was conducted to identify treatment outcomes. RESULTS: Incidence of abdominal TB was 7%, of all TB children with a mean age of 10.1 years. Mesenteric lymph nodes were involved in 67% and small intestine in 33% cases. Surgery was required in 22 children. 85% children completed treatment. Small intestine involvement had higher probability of undergoing surgery. Of the 70 children with complete follow up, 64 were well and 6 children succumbed to the disease. Older age, small intestine involvement and surgery were independently associated with higher mortality. CONCLUSION: Intestinal involvement is associated with greater need for surgical intervention and greater mortality. Adolescents have poorer outcomes. Further studies are required focusing on these individual subgroups to understand the patterns of presentation, causes for mortality and prevention. LEVEL OF EVIDENCE: Level 5.

2.
Front Genet ; 15: 1335768, 2024.
Article in English | MEDLINE | ID: mdl-38638122

ABSTRACT

Rare disease (RD) is a term used to describe numerous, heterogeneous diseases that are geographically disparate. Approximately 400 million people worldwide live with an RD equating to roughly 1 in 10 people, with 71.9% of RDs having a genetic origin. RDs present a distinctive set of challenges to people living with rare diseases (PLWRDs), their families, healthcare professionals (HCPs), healthcare system, and societies at large. The possibility of inheriting a genetic disease has a substantial social and psychological impact on affected families. In addition to other concerns, PLWRDs and their families may feel stigmatized, experience guilt, feel blamed, and stress about passing the disease to future generations. Stigma can affect all stages of the journey of PLWRDs and their families, from pre-diagnosis to treatment access, care and support, and compliance. It adversely impacts the quality of life of RD patients. To better explore the impact of stigma associated with genetic testing for RDs, we conducted a literature search on PubMed and Embase databases to identify articles published on stigma and RDs from January 2013 to February 2023. There is a dearth of literature investigating the dynamics of stigma and RD genetic testing. The authors observed that the research into the implications of stigma for patient outcomes in low- and middle-income countries (LMICs) and potential interventions is limited. Herein, the authors present a review of published literature on stigma with a focus on RD genetic testing, the associated challenges, and possible ways to address these.

3.
J Nepal Health Res Counc ; 20(4): 1008-1012, 2023 Jul 20.
Article in English | MEDLINE | ID: mdl-37489694

ABSTRACT

Genodermatoses are group of genetic disorders that present with cutaneous manifestations. The exact prevalence on many of these conditions are unknown due to its rarity, need of specialized tests for diagnosis and lack of proper reporting system. Most of the patients are faced with life-long disability and associated stigma. There is a need for specialized centers for proper diagnosis of these conditions and a very elaborated yet simple reporting system in Nepal. These rare conditions should be kept in priority by the government in align with the sustainable development goals to ensure healthy-lives and promote well-being for all. A wider engagement of patient-led support groups might be useful in providing necessary information on the disease to the general population and alleviate the stigma associated with these diseases. Keywords: Epidermolysis bullosa; genodermatoses; rare diseases; Nepal.


Subject(s)
Health Status , Humans , Nepal , Rare Diseases , Social Stigma
4.
Article in English | MEDLINE | ID: mdl-36981643

ABSTRACT

This document provides a comprehensive summary of evidence on the current situation of rare diseases (RDs) globally and regionally, including conditions, practices, policies, and regulations, as well as the challenges and barriers faced by RD patients, their families, and caregivers. The document builds on a review of academic literature and policies and a process of validation and feedback by a group of seven experts from across the globe. Panelists were selected based on their academic merit, expertise, and knowledge regarding the RD environment. The document is divided into five main sections: (1) methodology and objective; (2) background and context; (3) overview of the current situation and key challenges related to RDs covering six dimensions: burden of disease, patient journey, social impact, disease management, RD-related policies, and research and development; (4) recommendations; and (5) conclusions. The recommendations are derived from the discussion undertaken by the experts on the findings of this review and provide a set of actionable solutions to the challenges and barriers to improving access to RD diagnosis and treatment around the world. The recommendations can support critical decision-making, guiding efforts by a broad range of RDs stakeholders, including governments, international organizations, manufacturers, researchers, and patient advocacy groups.


Subject(s)
Health Policy , Rare Diseases , Humans , Rare Diseases/diagnosis , Rare Diseases/therapy
5.
Biotechnol Lett ; 45(3): 357-370, 2023 Mar.
Article in English | MEDLINE | ID: mdl-36707452

ABSTRACT

OBJECTIVE: Establishing cell lines with enhanced protein production requires a deep understanding of the cellular dynamics and cell line stability. The aim of the study is to investigate the impact of long term culturing (LTC) on cell morphology and altered cellular functions possibly leading to phenotypic drift, impacting product yield and quality. Study highlights the orthogonal cellular and analytical assay toolbox to define cell line stability for optimal culture performance and product quality. METHODS: We investigated recombinant monoclonal antibody (mAb) expressing CHO cells for 60 passages or 180 generations and assessed the cell growth characteristics and morphology by confocal and scanning electron microscopy. Quality attributes of expressed mAb is accessed by performing charge variants, glycan, and host cell protein analysis. RESULTS: We observed a 1.65-fold increase in viable cell population and 1.3-fold increase in cell specific growth rate. A 2.5-fold decrease in antibody titer and abatement of actin filament indicate cellular phenotypic drift. Mitochondrial membrane potential (∆ΨM) signified cell health and metabolic activity during LTC. Host cell protein production is reduced by 1.8-fold. Charge heterogeneity was perturbed with 12.5% and 43% reduction in abundance of acidic and basic charge variants respectively. Glycan profile indicated a decline in fucosylation with 17% increase in galactosylated species as compared with early passaged cells. CONCLUSION: LTC impinges on cellular phenotype as well as the quality of the expressed antibody, suggesting a defined subculturing limit to retain stable protein expression and cell morphology to achieve consistent product quality. Study signifies the changes in cellular and metabolic markers, suggesting cellular and analytical toolbox which could play a significant role in defining cell characteristics and ensured product quality.


Subject(s)
Antibodies, Monoclonal , Polysaccharides , Cricetinae , Animals , Antibodies, Monoclonal/genetics , Cricetulus , CHO Cells , Recombinant Proteins/metabolism
6.
Expert Opin Pharmacother ; 24(3): 389-399, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36542800

ABSTRACT

INTRODUCTION: The process of drug approval involves extensive and expensive preclinical and clinical examination. Most drugs entering late-stage clinical trials get terminated for a variety of reasons including inability to achieve the primary endpoints or intolerable adverse effects. Only one-tenth of the drugs that enter clinical trials progress to Food and Drug Administration (FDA) regulatory submission. AREAS COVERED: This review offers insight into some of the attributes that may be responsible for a drug's failure in late-stage trials. Information from multiple open sources including PubMed articles published between 1989 and 2019, recent articles from authentic websites like www.ClinicalTrials.gov, www.fda.gov, and pharmaceutical news articles for the years between 2017 and 2021 were accumulated and summarized. Further, a few drug candidates that reached the phase III clinical trials but were discontinued at later stages have been presented as case studies. EXPERT OPINION: Ineluctable failures were observed due to insufficient knowledge about the mechanism of action where the disease progression stages are unclear. Other reasons were choice of patient population, late-stage treatment, and dosage. Adhering to the guidelines and recommendations provided by the regulatory authorities and learning from past failures, considerably reduce failure rates.


Subject(s)
Drug Approval , Drug-Related Side Effects and Adverse Reactions , Humans
7.
Saudi J Kidney Dis Transpl ; 34(6): 592-601, 2023 Nov 01.
Article in English | MEDLINE | ID: mdl-38725209

ABSTRACT

Acute kidney injury (AKI) is common in premature newborns and is associated with high mortality. It is unclear which risk factors lead to AKI in these neonates. We aimed to determine the incidence, risk factors, and outcomes of AKI in preterm neonates in the neonatal intensive care unit (NICU). They were screened and staged for AKI as per the amended neonatal criteria of Kidney Disease Improving Global Outcomes and followed up until discharge or death. Serum creatinine levels and urine output were measured. The incidence of AKI was 18.5% (37/200 neonates). The majority developed non-oliguric AKI. The risk factors significantly associated with AKI in neonates were the presence of sepsis, birth asphyxia, shock, respiratory distress syndrome, and hypothermia. The majority of neonates with AKI had a birthweight <1500 g and a gestational age of <32 weeks and had a higher risk of mortality, in contrast to than those without AKI. Mortality and NICU stay were significantly higher among those with Stage 3 AKI compared with Stage 2 and Stage 1 AKI. To prevent AKI and reduce the burden of high mortality in premature neonates, it is essential to prevent sepsis, birth asphyxia, and respiratory distress syndrome, as well as to detect shock and patent ductus arteriosus as early as possible. There is a need for good antenatal care to reduce the burden of prematurity.


Subject(s)
Acute Kidney Injury , Gestational Age , Infant, Premature , Intensive Care Units, Neonatal , Humans , Infant, Newborn , Acute Kidney Injury/epidemiology , Acute Kidney Injury/therapy , Acute Kidney Injury/mortality , Acute Kidney Injury/diagnosis , Risk Factors , India/epidemiology , Incidence , Female , Male , Intensive Care Units, Neonatal/statistics & numerical data , Infant, Premature, Diseases/epidemiology , Infant, Premature, Diseases/mortality , Infant, Premature, Diseases/therapy , Birth Weight , Asphyxia Neonatorum/mortality , Asphyxia Neonatorum/epidemiology , Asphyxia Neonatorum/complications , Asphyxia Neonatorum/therapy
8.
Orphanet J Rare Dis ; 16(1): 119, 2021 03 05.
Article in English | MEDLINE | ID: mdl-33673852

ABSTRACT

BACKGROUND: This study assesses the areas and extent of impact of the Coronavirus Disease of 2019 (COVID-19) pandemic on rare disease (RD) organisations in the Asia Pacific region. There is no existing literature that focuses on such impact on RD organisations in any jurisdictions, nor RD populations across multiple jurisdictions in the Asia Pacific region. A cross-sectional survey was distributed to RD organisations between April and May 2020. Quantitative and qualitative data on the impact of COVID-19 on RD organisations and patients were collected from the organisation representative's perspective. Qualitative data was analysed using thematic analysis. A follow-up focus group meeting was conducted in August 2020 to validate the survey findings and to discuss specific needs, support and recommendations for sustainable healthcare systems during the pandemic. RESULTS: A total of 80 RD organisations from Australia, Hong Kong Special Administrative Region of China, India, Japan, mainland China, Malaysia, New Zealand, the Philippines, Singapore and Taiwan participated in the study. Of all, 89% were concerned about the impact of pandemic on their organisations. Results indicate that 63% of the organisations functioned at a reduced capacity and 42% stated a decrease in funding as their biggest challenge. Overall, 95% believed their patients were impacted, particularly in healthcare access, social lives, physical health, psychological health and financial impact. Specifically, 43% identified the reduced healthcare access as their top impact, followed by 26% about the impact on daily living and social life. Focus group meeting discussed differential impact across jurisdictions and point towards telemedicine and digitalisation as potential solutions. CONCLUSIONS: This serves as the first study to assess the impact of COVID-19 on RD patients and organisations across multiple jurisdictions in the Asia Pacific region, identifying major themes on the impact on both RD patients and organisations. By including 80 organisations from ten jurisdictions, our study presents the most comprehensive assessment of the pandemic's impact to date. It highlights the need for mental health support and sheds light on moving towards telemedicine and digitalisation of organisation operation, which constitutes a sustainable model in times of pandemics and beyond.


Subject(s)
COVID-19/complications , COVID-19/epidemiology , Pandemics , Rare Diseases/complications , Societies/organization & administration , Asia/epidemiology , COVID-19/virology , Cross-Sectional Studies , Humans , Oceania/epidemiology , SARS-CoV-2/isolation & purification
9.
Int J Biol Macromol ; 137: 95-106, 2019 Sep 15.
Article in English | MEDLINE | ID: mdl-31255625

ABSTRACT

Novel developments in surgical glues for sealing wounds, surgical incision and tissue healing was inspired by limitations related to other surgical techniques. Sealants or bioadhesives are considered as a promising candidate over sutures, staples for sealing of air and gas leakages with minimal scarring in different surgeries. Their physical, biological properties and adhesive strength have encouraged many surgeons for employing them in clinical practice. Commonly, various natural biopolymers such as fibrin, collagen, gelatin, albumin, chitosan are used for the preparation of surgical glues. These biopolymers mimic the mechanism of physiological interaction such as blood clotting process. Besides natural polymers, synthetic polymers are also incorporated in surgical glues. Several sealants or adhesives are available commercially and have been used for neurosurgery, orthopaedic, periodontal, ophthalmic, cardiovascular, pneumothoracic, gastrointestinal, plastic and reconstructive surgery. This article focuses on providing a comprehensive review on the development of surgical glues, their unique features and application in clinical practice. In addition to the advantages of these sealants, the insights on their limitations, especially biocompatibility and tissue elasticity have been covered. Although the use of surgical glues is increasing gradually, the next generation of products should be marketed after extensive clinical studies and adequate safety and efficacy data.


Subject(s)
Surgical Procedures, Operative , Tissue Adhesives , Animals , Biological Products/chemistry , Humans , Polymers/chemical synthesis , Polymers/chemistry , Tissue Adhesives/chemistry , Tissue Adhesives/pharmacology
10.
Spectrochim Acta A Mol Biomol Spectrosc ; 212: 94-104, 2019 Apr 05.
Article in English | MEDLINE | ID: mdl-30616168

ABSTRACT

This work presents the synthesis, structural characterization and biological affinity of the newly synthesized copper(II) complexes with the first antibacterial quinolone drug nalidixic acid (nal) or N-donor ligand 2,2'­dipyridylamine (bipyam). [Cu(II)(nal)(bipyam)Cl], (2) reveals a distorted square pyramidal based geometry in Cu(II) atom confirmed by X-ray crystallography technique. The theoretical stabilities and optimized structures of the complex were obtained from DFT calculations. The ability of the complexes to bind with calf thymus DNA (CT DNA) were investigated by electronic absorption, fluorescence, circular dichroism, and viscosity measurements techniques. The experimental results reveal that the complexes strongly interact with CT DNA via intercalative mode but complex 2 exhibits the highest affinity giving Kb=3.91±0.13×106, M-1. The fluorescence spectroscopy measurements show that both complexes have the superior ability to the replacement of EtBr from DNA-bound EtBr solution and bind to DNA through intercalative mode. Both complex also shows the superior affinity towards proteins with comparatively high binding constant values which have been further revealed by fluorescence spectroscopy measurements. Molecular docking analysis indicates that the interaction of the complexes and proteins are stabilized by hydrogen bonding and hydrophobic interaction. Furthermore, the results of in vitro cytotoxicity reveal that the complex 2 has excellent cytotoxicity than 1 against human breast cancer cell lines (MCF-7).


Subject(s)
2,2'-Dipyridyl/analogs & derivatives , Coordination Complexes/chemistry , Copper/chemistry , DNA/chemistry , Molecular Docking Simulation , Nalidixic Acid/chemistry , 2,2'-Dipyridyl/chemical synthesis , 2,2'-Dipyridyl/chemistry , Cell Death , Circular Dichroism , Coordination Complexes/chemical synthesis , Density Functional Theory , Humans , Kinetics , MCF-7 Cells , Molecular Conformation , Protein Binding , Serum Albumin, Bovine/metabolism , Serum Albumin, Human/metabolism , Solubility , Spectrometry, Fluorescence , Spectrophotometry, Ultraviolet , Spectroscopy, Fourier Transform Infrared , Viscosity
11.
Genet Med ; 20(6): 608-613, 2018 06.
Article in English | MEDLINE | ID: mdl-29758563

ABSTRACT

PurposeTo determine feasibility and utility of newborn screening for spinal muscular atrophy (SMA) in New York State.MethodsWe validated a multiplex TaqMan real-time quantitative polymerase chain reaction assay using dried blood spots for SMA. From January 2016 to January 2017, we offered, consented, and screened 3,826 newborns at three hospitals in New York City and tested newborns for the deletion in exon 7 of SMN1.ResultsNinety-three percent of parents opted in for SMA screening. Overall the SMA carrier frequency was 1.5%. We identified one newborn with a homozygous SMN1 deletion and two copies of SMN2, which strongly suggests the severe type 1 SMA phenotype. The infant was enrolled in the NURTURE clinical trial and was first treated with Spinraza at age 15 days. She is now age 12 months, meeting all developmental milestones, and free of any respiratory issues.ConclusionOur pilot study demonstrates the feasibility of population-based screening, the acceptance by families, and the benefit of newborn screening for SMA. We suggest that SMA be considered for addition to the national recommended uniform screening panel.


Subject(s)
Muscular Atrophy, Spinal/diagnosis , Neonatal Screening/methods , Survival of Motor Neuron 1 Protein/genetics , Exons , Female , Gene Deletion , Gene Dosage , Humans , Infant , Infant, Newborn , Male , Muscular Atrophy, Spinal/genetics , New York , Pilot Projects , Survival of Motor Neuron 1 Protein/physiology
12.
Comput Biol Chem ; 69: 147-152, 2017 Aug.
Article in English | MEDLINE | ID: mdl-28420545

ABSTRACT

BACKGROUND: TSPO translocator protein, encoded in humans by the Tspo gene plays a crucial role in mitochondria mediated apoptosis and necrotic cell death through its association with Mitochondrial Permeability Transition pore (MPTP). It has been shown that this function can be exploited as a potential treatment for human Glioblastoma Multiforme. In this study, a novel robust fragment based QSAR model has been developed for a series of 4-phenylquinazoline-2-carboxamides experimentally known to be ligands for TSPO, thus triggering apoptotic mechanism cascade. RESULTS: Model developed showed satisfactory statistical parameters for the experimentally reported dataset (r2=0.8259, q2=0.6788, pred_r2=0.8237 and F-test=37.9). Low standard error values (r2_se=0.253, q2_se=0.34, pred_r2_se=0.14) confirmed the accuracy of the generated model. The model obtained had 4 descriptors, namely, R1-Volume, R2-SsCH3E-index, R3-SsCH3count and R5-EpsilonR. Two of them had positive contribution while the other two had negative correlation. CONCLUSION: The high binding affinity and the presence of essential structural features in these compounds make them an ideal choice for the consideration as potent anti-GBM drugs. Activity predicted by GQSAR model reinforces their potential as worthy candidates for drugs against GBM. The detailed analysis carried out in this study provides a substantial basis for the prospective design and development of novel 4-phenylquinazoline-2-carboxamide compounds as TSPO ligands capable of inducing apoptosis in cancer cells.


Subject(s)
Antineoplastic Agents/pharmacology , Combinatorial Chemistry Techniques , Glioblastoma/drug therapy , Glioblastoma/pathology , Quantitative Structure-Activity Relationship , Quinazolines/pharmacology , Antineoplastic Agents/chemistry , Cell Proliferation/drug effects , Dose-Response Relationship, Drug , Drug Screening Assays, Antitumor , Humans , Models, Molecular , Molecular Dynamics Simulation , Molecular Structure , Quinazolines/chemistry
13.
BMC Bioinformatics ; 16 Suppl 19: S10, 2015.
Article in English | MEDLINE | ID: mdl-26695135

ABSTRACT

BACKGROUND: The human immunodeficiency virus (HIV-1) is a retrovirus causing acquired immunodeficiency syndrome (AIDS), which has become a serious problem across the world and has no cure reported to date. Human immunodeficiency virus (HIV-1) protease is an attractive target for antiviral treatment and a number of therapeutically useful inhibitors have been designed against it. The emergence of drug resistant mutants of HIV-1 poses a serious problem for conventional therapies that have been used so far. Until now, thirteen protease inhibitors (PIs), major mutation sites and many secondary mutations have been listed in the HIV Drug Resistance Database. In this study, we have studied the effect of the V77I mutation in HIV-PR along with the co-occurring mutations L33F and K20T through multi-nanosecond molecular dynamics simulations. V77I is known to cause Nelfinavir (NFV) resistance in the subtype B population of HIV-1 protease. We have for the first time reported the effect of this clinically relevant mutation on the binding of Nelfinavir and the conformational flexibility of the protease. RESULTS: Two HIV-PR mutants have been considered in this study - the Double Mutant Protease (DBM) V77I-L33F and Triple Mutant Protease (TPM) V77I-K20T-L33F. The molecular dynamics simulation studies were carried out and the RMSD trajectories of the unliganded wild type and mutated protease were found to be stable. The binding affinity of NFV with wild type HIV-PR was very high with a Glide XP docking score of -9.3 Kcal/mol. NFV showed decreased affinity towards DBM with a docking score of -8.0 Kcal/mol, whereas its affinity increased towards TPM (Glide XP score: -10.3). Prime/MM-GBSA binding free energy of the wild type, DBM and TPM HIV-PR docked structures were calculated as -38.9, -11.1 and -42.6 Kcal/mol respectively. The binding site cavity volumes of wild type, DBM and TPM protease were 1186.1, 1375.5 and 1042.5 Å3 respectively. CONCLUSION: In this study, we have studied the structural roles of the two HIV-PR mutations by conducting molecular dynamics simulation studies of the wild type and mutant HIV-1 PRs. The present study proposes that DBM protease showed greater flexibility and the flap separation was greater with respect to the wild type protease. The cavity size of the MD-stabilized DBM was also found to be increased, which may be responsible for the decreased interaction of Nelfinavir with the cavity residues, thus explaining the decreased binding affinity. On the other hand, the binding affinity of NFV for TPM was found to be enhanced, accounted for by the decrease in cavity size of the mutant which facilitated strong interactions with the flap residues. The flap separation of TPM was less than the wild type protease and the decreased cavity size may be responsible for its lower resistance, and hence, may be the reason for its lower clinical relevance.


Subject(s)
Drug Resistance, Viral/genetics , HIV Protease/genetics , HIV-1/enzymology , HIV-1/genetics , Mutation/genetics , Nelfinavir/chemistry , Nelfinavir/pharmacology , Binding Sites/genetics , Catalytic Domain , HIV Infections/genetics , HIV Protease Inhibitors/pharmacology , HIV-1/isolation & purification , Humans , Hydrogen Bonding , Hydrophobic and Hydrophilic Interactions , Ligands , Molecular Docking Simulation , Molecular Dynamics Simulation , Thermodynamics
14.
Comput Biol Chem ; 59 Pt A: 37-47, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26410242

ABSTRACT

Drug resistant tuberculosis has threatened all the advances that have been made in TB control at the global stage in the last few decades. DNA gyrase enzymes are an excellent target for antibacterial drug discovery as they are involved in essential functions like DNA replication. Here we report, a successful application of high throughput virtual screening (HTVS) to identify an inhibitor of Mycobacterium DNA gyrase targeting the wild type and the most prevalent three double mutants of quinolone resistant DNA gyrase namely A90V+D94G, A74S+D94G and A90V+S91P. HTVS of 179.299 compounds gave five compounds with significant binding affinity. Extra presicion (XP) docking and MD simulations gave a clear view of their interaction pattern. Among them, chebulinic acid (CA), a phytocompound obtained from Terminalia chebula was the most potent inhibitor with significantly high XP docking score, -14.63, -16.46, -15.94 and -15.11 against wild type and three variants respectively. Simulation studies for a period of 16 ns indicated stable DNA gyrA-CA complex formation. This stable binding would result in inhibition of the enzyme by two mechanisms. Firstly, binding of CA causes displacement of catalytic Tyr129 away from its target DNA-phosphate molecule from 1.6 Å to 3.8-7.3 Å and secondly, by causing steric hindrance to the binding of DNA strand at DNA binding site of enzyme. The combined effect would result in loss of cleavage and religation activity of enzyme leading to bactericidal effect on tuberculosis. This phytocompound displays desirable quality for carrying forward as a lead compound for anti-tuberculosis drug development. The results presented here are solely based on computations and need to be validated experimentally in order to assert the proposed mechanism of action.


Subject(s)
Anti-Bacterial Agents/pharmacology , DNA Gyrase/metabolism , Hydrolyzable Tannins/pharmacology , Mycobacterium tuberculosis/drug effects , Mycobacterium tuberculosis/enzymology , Anti-Bacterial Agents/chemistry , Binding Sites , DNA, Bacterial/metabolism , High-Throughput Screening Assays , Hydrolyzable Tannins/chemistry , Microbial Sensitivity Tests , Models, Molecular , Molecular Structure , Mycobacterium tuberculosis/metabolism , Protein Binding , Structure-Activity Relationship , Tuberculosis, Multidrug-Resistant/drug therapy
15.
J Recept Signal Transduct Res ; 35(6): 626-33, 2015.
Article in English | MEDLINE | ID: mdl-26390942

ABSTRACT

INTRODUCTION: Cancer is characterized by uncontrolled cell growth and genetic instabilities. The human Aurora-A kinase protein plays a crucial role in spindle assembly during mitosis and is activated by another candidate oncogene, targeting protein for Xklp2 (TPX2). It has been proposed that dissociation of Aurora A-TPX2 complex leads to disruption of mitotic spindle apparatus, thereby preventing cell division and further tumor growth. MATERIALS AND METHODS: A large natural compound library was docked against the active site of Aurora A-TPX2 complex. The protein-ligand complexes were subjected to molecular dynamics simulation to ascertain their binding stability. The drug properties of the compounds were analyzed to observe their drug-like properties. RESULTS: The virtual screening of natural compound library yielded two high scoring compounds, the first compound CTOM [ZINC ID: 38143674] (Glide score: -9.49) was stable for 17 ns while the second TTOM (Glide score: -9.07) was stable for 15 ns. While CTOM interacted with His280, Thr288 of Aurora A and Tyr34, Lys38 of TPX2, TTOM interacted with Arg285 and Arg286 in addition to the residues involved with CTOM. CONCLUSIONS: We report two natural compounds as potential drugs leads for the disruption of this complex. These ligands show a preferable docking score and have many drugs like properties within in the range of 95% of known drugs. The study provides evidence that CTOM and TTOM can efficiently inhibit the TPX2-mediated activation of Aurora A. Thus, it paves way for an elaborate investigation and establishes the importance of computational approaches as time- and cost-effective techniques.


Subject(s)
Aurora Kinase A/chemistry , Biological Products/pharmacology , Cell Cycle Proteins/chemistry , Microtubule-Associated Proteins/chemistry , Molecular Dynamics Simulation , Nuclear Proteins/chemistry , Small Molecule Libraries/pharmacology , Aurora Kinase A/metabolism , Binding Sites , Cell Cycle Proteins/metabolism , Humans , Microtubule-Associated Proteins/metabolism , Models, Molecular , Nuclear Proteins/metabolism , Protein Conformation
16.
Comb Chem High Throughput Screen ; 18(9): 881-91, 2015.
Article in English | MEDLINE | ID: mdl-26111950

ABSTRACT

Survival of cells and maintenance of genome depend on detection and repair of damaged DNA through intricate mechanisms. Cancer treatment relies on chemotherapy or radiation therapy that kills neoplastic cells by causing immense damage to the DNA. In many cases, escalated DNA repair mechanism leads to resistance against these therapies and therefore, there is a need to expand the interest in developing drugs that can sensitize the cells to such therapies by interfering with the DNA repair mechanism. Several studies have suggested a link between over expression of the primary mammalian enzyme, Apurinic/Apyrimidinic Endonuclease (APE1), responsible for abasic (or AP) site removal in the DNA and resistance of these cells to cancer therapy, whereas APE1 down-regulation sensitizes the cells to DNA damaging agents. Thus, the current treatment efficacy can be improved by aiding to selective sensitization of cancer cells and protection of normal cells. In the present study, we have used machine learning based approach by selecting assorted compounds with known activity for APE1 and constructed a range of in silico predictive classification models to discriminate between the inhibitors and non-inhibitors. These models can be applied to numerous other unscreened compounds to select the ones which are more likely to be the inhibitors for APE1. We have further found the common molecular substructures which were associated with the molecular activity of the compounds using a substructure search approach.


Subject(s)
Drug Resistance, Neoplasm/drug effects , Informatics , Antineoplastic Agents/pharmacology , DNA Damage/drug effects , DNA Repair/drug effects , DNA-(Apurinic or Apyrimidinic Site) Lyase/physiology , Endonucleases , Multifunctional Enzymes
17.
Gene ; 570(1): 115-21, 2015 Oct 01.
Article in English | MEDLINE | ID: mdl-26055089

ABSTRACT

The hepatitis C virus (HCV) infection is a primary cause of chronic hepatitis which eventually progresses to cirrhosis and in some instances might advance to hepatocellular carcinoma. According to the WHO report, HCV infects 130-150 million people globally and every year 350,000 to 500,000 people die from hepatitis C virus infection. Great achievement has been made in viral treatment evolution, after the development of HCV NS3/4A protease inhibitor (Boceprevir). However, efficacy of Boceprevir is compromised by the emergence of drug resistant variants. The molecular principle behind drug resistance of the protease mutants such as (V36M, T54S and R155K) is still poorly understood. Therefore in this study, we employed a series of computational strategies to analyze the binding of antiviral drug, Boceprevir to HCV NS3/4A protease mutants. Our results clearly demonstrate that the point mutations (V36M, T54S and R155K) in protease are associated with lowering of its binding affinity with Boceprevir. Exhaustive analysis of the simulated Boceprevir-bound wild and mutant complexes revealed variations in hydrophobic interactions, hydrogen bond occupancy and salt bridge interactions. Also, substrate envelope analysis scrutinized that the studied mutations reside outside the substrate envelope which may affect the Boceprevir affinity towards HCV protease but not the protease enzymatic activity. Furthermore, structural analyses of the binding site volume and flexibility show impairment in flexibility and stability of the binding site residues in mutant structures. In order to combat Boceprevir resistance, renovation of binding interactions between the drug and protease may be valuable. The structural insight from this study reveals the mechanism of the Boceprevir resistance and the results can be valuable for the design of new PIs with improved efficiency.


Subject(s)
Antiviral Agents/chemistry , Hepacivirus/enzymology , Proline/analogs & derivatives , Viral Nonstructural Proteins/genetics , Antiviral Agents/pharmacology , Catalytic Domain , Drug Resistance, Viral , Hepacivirus/genetics , Hydrogen Bonding , Molecular Dynamics Simulation , Mutation, Missense , Proline/chemistry , Proline/pharmacology , Viral Nonstructural Proteins/chemistry
18.
Syst Synth Biol ; 9(1-2): 33-43, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25972987

ABSTRACT

Cancer cells have upregulated DNA repair mechanisms, enabling them survive DNA damage induced during repeated rapid cell divisions and targeted chemotherapeutic treatments. Cancer cell proliferation and survival targeting via inhibition of DNA repair pathways is currently a very promiscuous anti-tumor approach. The deubiquitinating enzyme, USP1 is known to promote DNA repair via complexing with UAF1. The USP1/UAF1 complex is responsible for regulating DNA break repair pathways such as trans-lesion synthesis pathway, Fanconi anemia pathway and homologous recombination. Thus, USP1/UAF1 inhibition poses as an efficient anti-cancer strategy. The recently made available high throughput screen data for anti USP1/UAF1 activity prompted us to compute bioactivity predictive models that could help in screening for potential USP1/UAF1 inhibitors having anti-cancer properties. The current study utilizes publicly available high throughput screen data set of chemical compounds evaluated for their potential USP1/UAF1 inhibitory effect. A machine learning approach was devised for generation of computational models that could predict for potential anti USP1/UAF1 biological activity of novel anticancer compounds. Additional efficacy of active compounds was screened by applying SMARTS filter to eliminate molecules with non-drug like features. The structural fragment analysis was further performed to explore structural properties of the molecules. We demonstrated that modern machine learning approaches could be efficiently employed in building predictive computational models and their predictive performance is statistically accurate. The structure fragment analysis revealed the structures that could play an important role in identification of USP1/UAF1 inhibitors.

19.
Genes Chromosomes Cancer ; 52(10): 961-75, 2013 Oct.
Article in English | MEDLINE | ID: mdl-23913792

ABSTRACT

Tyrosine kinases orchestrate key cellular signaling pathways and their dysregulation is often associated with cellular transformation. Several recent cases in which inhibitors of tyrosine kinases have been successfully used as anticancer agents have underscored the importance of this class of proteins in the development of targeted cancer therapies. We have carried out a large-scale loss-of-function analysis of the human tyrosine kinases using RNA interference to identify novel survival factors for breast cancer cells. In addition to kinases with known roles in breast and other cancers, we identified several kinases that were previously unknown to be required for breast cancer cell survival. The most surprising of these was the cytosolic, nonreceptor tyrosine kinase, Bruton's tyrosine kinase (BTK), which has been extensively studied in B cell development. Down regulation of this protein with RNAi or inhibition with pharmacological inhibitors causes apoptosis; overexpression inhibits apoptosis induced by Doxorubicin in breast cancer cells. Our results surprisingly show that BTK is expressed in several breast cancer cell lines and tumors. The predominant form of BTK found in tumor cells is transcribed from an alternative promoter and results in a protein with an amino-terminal extension. This alternate form of BTK is expressed at significantly higher levels in tumorigenic breast cells than in normal breast cells. Since this protein is a survival factor for these cells, it represents both a potential marker and novel therapeutic target for breast cancer.


Subject(s)
Apoptosis/physiology , Breast Neoplasms/enzymology , Breast Neoplasms/pathology , Protein-Tyrosine Kinases/metabolism , Agammaglobulinaemia Tyrosine Kinase , Base Sequence , Breast/chemistry , Breast Neoplasms/chemistry , Breast Neoplasms/genetics , Cell Line , Cell Line, Tumor , Cell Proliferation , Female , Humans , Isoenzymes/chemistry , Isoenzymes/genetics , Isoenzymes/metabolism , Molecular Sequence Data , Protein-Tyrosine Kinases/chemistry , Protein-Tyrosine Kinases/genetics , RNA Interference
20.
Cytojournal ; 10: 5, 2013.
Article in English | MEDLINE | ID: mdl-23599724

ABSTRACT

OBJECTIVES: Fine needle aspiration cytology (FNAC) has been employed in pre-operative diagnosis of salivary gland lesions for many years. Various studies in the existing literature have shown a wide range of sensitivity and diagnostic accuracy of cytologic diagnosis. This study was aimed at evaluating salivary gland FNAC for sensitivity, specificity and diagnostic accuracy at a tertiary care center. MATERIALS AND METHODS: This study included 80 patients who underwent pre-operative FNAC followed by surgical procedure and histologic examination. The histologic diagnosis was considered as the gold standard. FNAC diagnosis was compared with the final histologic impression and concordance assessed. Sensitivity, specificity and diagnostic accuracy of FNAC for malignant lesions were calculated. RESULTS: Of the 80 cases, majority (67.5%) involved the parotid gland. Eight cases (10%) were non-neoplastic lesions, comprised of sialadenitis, retention cyst and sialadenosis. Of a total of 72 neoplasms, 58 were benign and 14 were malignant salivary gland tumors. A cyto-histologic concordance of benign diagnosis was achieved in 85.7% of cases and for malignant lesions in 92.8% of the malignant tumors. FNAC showed a sensitivity of 92.8%, specificity of 93.9%, a positive predictive value of 81.2% and negative predictive value of 98.4% for malignant salivary gland tumors. There was one false-negative diagnosis and four false-positive cases diagnosed on FNAC. CONCLUSION: FNAC continues to be a reliable diagnostic technique in hands of an experienced cytopathologist. The sensitivity of diagnosis of malignant lesions is high, though the rate of tumor type-specific characterization is lower, due to variable cytomorphology. In difficult cases, histologic examination may be employed for accurate diagnosis.

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