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1.
Mil Med ; 2024 Apr 30.
Article in English | MEDLINE | ID: mdl-38687601

ABSTRACT

INTRODUCTION: Approximately 9 million veterans receive health care at the Veterans Health Administration, many of whom have psychiatric illnesses. The military continues to have higher rates of psychiatric illness compared to the civilian population. Having a diagnosis such as posttraumatic stress disorder or depression may create challenges in using health care services, such as surgery. The aim of this study was to evaluate eye surgery cancellation, risk factors for cancellation, and areas for intervention within the VA. MATERIALS AND METHODS: This was a single-center retrospective cohort study. The Veteran Health Information Systems and Technology Architecture were queried to identify all surgical requests at the West Los Angeles VA in 2019. Data collection included sociodemographic information and comorbid medical conditions, including psychiatric illness. Exploratory analyses using univariate logistic regression were used to evaluate factors associated with surgery cancellation. RESULTS: A total of 1,115 surgical requests were identified with a cancellation rate of 23.7% (n = 270). Sociodemographic factors were similar between those with completed and cancelled surgery. However, having a psychiatric diagnosis correlated with surgery cancellation. For all subspecialties, patients with schizophrenia were more likely to have cancellation (odds ratio [OR], 2.53, P = .04). For retina surgery, patients with posttraumatic stress disorder were more likely to have cancellation (OR, 4.23, P = .01). Glaucoma patients with anxiety (OR, 5.78, P = .05) and depression (OR, 4.05, P = .04) were more likely to have cancellation. CONCLUSIONS: There was a significant amount of eye surgery cancellations in veterans with variation by subspecialty and comorbid conditions. Having a psychiatric illness was correlated with increased rates of surgery cancellation amongst veterans. Areas to improve surgical utilization include risk stratification and increased support of vulnerable patients before surgery.

2.
J Proteome Res ; 23(1): 16-24, 2024 01 05.
Article in English | MEDLINE | ID: mdl-37985371

ABSTRACT

α-Synuclein (α-Syn) misfolding and its presence in Lewy bodies are observed in almost all Parkinson's disease (PD) patients. Basic biomedical research would benefit from a quick, low-cost approach to purifying α-Syn and developing in vitro and in vivo models for PD. Several research groups utilize PFF-based models, yet the production of α-Syn PFFs is inconsistent, resulting in nonconclusive findings. Some research laboratories prepare recombinant α-Syn (r α-Syn) by molecular cloning to overexpress α-Syn with various purifying techniques. Laboratory-to-laboratory protocols cause considerable variability and sometimes contradictory findings. PD researchers spend more on protein than solving α-Syn's riddles. This article uncovered a novel method for expressing and purifying r α-Syn validated through gage reproducibility and repeatability (Gage R&R). For the production of r α-Syn, we have employed the ability of a high-cell-density-based expression system to overexpress protein in BL21(DE3). A simple, high-throughput, nonchromatographical purification protocol has been devised to facilitate research with higher reproducibility, which was validated through Gage R&R. A crossover experimental design was utilized, and the purified protein was characterized using orthogonal high-end analytical methods, which displayed higher similarity between the isolated r α-Syn. Batch-to-batch variability was the least for produced protein and hence can be utilized for exploring the iceberg of PD.


Subject(s)
Biomedical Research , Parkinson Disease , Humans , alpha-Synuclein/genetics , alpha-Synuclein/metabolism , Reproducibility of Results , Parkinson Disease/genetics , Parkinson Disease/metabolism , Lewy Bodies
3.
ACS Pharmacol Transl Sci ; 6(3): 334-354, 2023 Mar 10.
Article in English | MEDLINE | ID: mdl-36923110

ABSTRACT

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.

4.
ACS Pharmacol Transl Sci ; 6(1): 40-51, 2023 Jan 13.
Article in English | MEDLINE | ID: mdl-36654754

ABSTRACT

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.

5.
Appl Biochem Biotechnol ; 195(4): 2216-2234, 2023 Apr.
Article in English | MEDLINE | ID: mdl-35507252

ABSTRACT

Alzheimer's disease (AD) is a multifactorial neurodegenerative disorder characterized by memory loss, cognitive deterioration, and neuropsychiatric symptoms. Various drug targets implicated in AD are amyloid beta peptides, cholinesterase enzymes, and anti-amylogenic protein. Medicinal plants derived phytochemical constituents provide a vast pool of diverse compounds as a source of novel drugs. In view of this, the Caesalpinia bonducella seed extract and its active phytoconstituents were used to study the disease-modifying effects in Alzheimer's disease. The present study successfully demonstrated the therapeutic potential of various phytochemicals as it binds to multiple drug targets, resulting in inhibition of acetylcholinesterase (AChE) enzyme, butyrylcholinesterase (BuChE), BACE-1 enzyme, and anti-amylogenic protein as indicated by docking analysis. In conclusion, phytochemicals identified can be used as a suitable lead to developing a molecule that might have multi-targeted directed ligand (MTDL) potential and disease amelioration effects in Alzheimer's disease.


Subject(s)
Alzheimer Disease , Caesalpinia , Alzheimer Disease/drug therapy , Alzheimer Disease/metabolism , Butyrylcholinesterase/metabolism , Amyloid beta-Peptides/metabolism , Acetylcholinesterase/metabolism , Caesalpinia/metabolism , Cholinesterase Inhibitors/pharmacology , Cholinesterase Inhibitors/therapeutic use , Cholinesterase Inhibitors/chemistry , Molecular Docking Simulation
7.
Metab Brain Dis ; 37(8): 2853-2870, 2022 12.
Article in English | MEDLINE | ID: mdl-36178640

ABSTRACT

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.


Subject(s)
Parkinson Disease , Rotenone , Animals , Rats , Mice , Rotenone/toxicity , alpha-Synuclein/metabolism , Parkinson Disease/drug therapy , Parkinson Disease/metabolism , AMP-Activated Protein Kinases , Neuroprotection , Autophagy
8.
Mol Neurobiol ; 59(11): 6834-6856, 2022 Nov.
Article in English | MEDLINE | ID: mdl-36048341

ABSTRACT

Parkinson's disease (PD) is a chronic motor disorder, characterized by progressive loss of dopaminergic neurons. Numerous studies suggest that glucagon-like peptide-1 (GLP-1) secretagogue has a neuroprotective role in PD models. The present study evaluated potential of coffee bioactive compounds in terms of their ability to bind GPR-40/43 and tested the neuroprotective effect of best candidate on rotenone-induced PD mice acting via GLP-1 release. In silico molecular docking followed by binding free energy calculation revealed that chlorogenic acid (CGA) has a strong binding affinity for GPR-40/43 in comparison to other bioactive polyphenols. Molecular dynamics simulation studies revealed stable nature of GPR40-CGA and GPR43-CGA interaction and also provided information about the amino acid residues involved in binding. Subsequently, in vitro studies demonstrated that CGA-induced secretion of GLP-1 via enhancing cAMP levels in GLUTag cells. Furthermore, in vivo experiments utilizing rotenone-induced mouse model of PD revealed a significant rise in plasma GLP-1 after CGA administration (50 mg/kg, orally for 13 weeks) with concomitant increase in colonic GPR-40 and GPR-43 mRNA expression. CGA treatment also prevented rotenone-induced motor and cognitive impairments and significantly restored the rotenone-induced oxidative stress. Meanwhile, western blot results confirmed that CGA treatment downregulated rotenone-induced phosphorylated alpha-synuclein levels by upregulating PI3K/AKT signaling and inactivating GSK-3ß through the release of GLP-1. CGA treatment ameliorated rotenone-induced dopaminergic nerve degeneration and alpha-synuclein accumulation in substantia nigra and augmented mean density of dopaminergic nerve fibers in striatum. These findings demonstrated novel biological function of CGA as a GLP-1 secretagogue. An increase in endogenous GLP-1 may render neuroprotection against a rotenone mouse model of PD and has the potential to be used as a neuroprotective agent in management of PD.


Subject(s)
Chlorogenic Acid , Glucagon-Like Peptide 1 , Neuroprotective Agents , Parkinson Disease , Amino Acids , Animals , Chlorogenic Acid/pharmacology , Chlorogenic Acid/therapeutic use , Coffee/chemistry , Dopaminergic Neurons/metabolism , Glucagon-Like Peptide 1/metabolism , Glycogen Synthase Kinase 3 beta , Mice , Molecular Docking Simulation , Neuroprotective Agents/pharmacology , Neuroprotective Agents/therapeutic use , Parkinson Disease/drug therapy , Phosphatidylinositol 3-Kinases , Polyphenols/pharmacology , Polyphenols/therapeutic use , Proto-Oncogene Proteins c-akt , RNA, Messenger , Rotenone/toxicity , Secretagogues/pharmacology , alpha-Synuclein/metabolism
9.
Trials ; 23(1): 102, 2022 Jan 31.
Article in English | MEDLINE | ID: mdl-35101099

ABSTRACT

BACKGROUND: In the west, survival following treatment of childhood acute lymphoblastic leukaemia (ALL) approaches 90%. Outcomes in India do not exceed 70%. To address this disparity, the Indian Collaborative Childhood Leukaemia group (ICiCLe) developed in 2013 a contemporary treatment protocol for uniform risk-stratified management of first presentation ALL based on cytogenetics and minimal residual disease levels (MRD). A multicentre randomised clinical trial opened in 2016 (ICiCLe-ALL-14) and examines the benefit of randomised interventions to decrease toxicity and improve outcomes. METHODS: Patients 1-18 years with newly diagnosed ALL are categorised into four risk groups based on presentation features, tumour genetics and treatment response. Standard risk includes young (< 10 years) B cell precursor ALL (BCP-ALL) patients with low presentation leucocyte count (< 50 × 109/L) and no high-risk features. Intermediate risk includes BCP-ALL patients with no high-risk features but are older and have high presentation leucocyte counts and/or bulky disease. High risk includes BCP-ALL patients with any high-risk feature, including high-risk genetics, central nervous system leukaemia, poor prednisolone response at treatment day 8 and high MRD (≥ 0·01%) at the end of induction. Patients with T-lineage ALL constitute the fourth risk group. All patients receive four intensive treatment blocks (induction, consolidation, interim maintenance, delayed intensification) followed by 96 weeks of maintenance. Treatment intensity varies by risk group. Clinical data management is based on a web-based remote data capture system. The first randomisation examines the toxicity impact of a shorter induction schedule of prednisolone (3 vs 5 weeks) in young non-high-risk BCP-ALL. The second randomisation examines the survival benefit of substituting doxorubicin with mitoxantrone in delayed intensification for all patients. Primary outcome measures include event-free survival (overall, by risk groups), sepsis rates in induction (first randomisation) and event-free survival rates following second randomisation. DISCUSSION: ICiCLe-ALL-14 is the first multicentre randomised childhood cancer clinical trial in India. The pre-trial phase allowed standardisation of risk-stratification diagnostics and established the feasibility of collaborative practice, uniform treatment, patient enrolment and data capture. Pre-trial observations confirm the impact of risk-stratified therapy in reducing treatment-related deaths and costs. Uniform practice across centres allows patients to access care locally, potentially decreasing financial hardship and dislocation. TRIAL REGISTRATION: Clinical Trials Registry-India (CTRI) CTRI/2015/12/006434 . Registered on 11 December 2015.


Subject(s)
Neoplasm Recurrence, Local , Precursor Cell Lymphoblastic Leukemia-Lymphoma , Humans , Multicenter Studies as Topic , Neoplasm, Residual , Precursor Cell Lymphoblastic Leukemia-Lymphoma/diagnosis , Precursor Cell Lymphoblastic Leukemia-Lymphoma/drug therapy , Precursor Cell Lymphoblastic Leukemia-Lymphoma/genetics , Prospective Studies , Randomized Controlled Trials as Topic , Treatment Outcome
10.
Indian J Pharmacol ; 54(6): 417-422, 2022.
Article in English | MEDLINE | ID: mdl-36722553

ABSTRACT

BACKGROUND: Mucormycosis is a rare but serious fungal infection which has dramatically increased in post-COVID patients. There is a paucity of safety data on amphotericin B (amphoB) used for mucormycosis treatment. OBJECTIVES: The objective of this prospective, observational, active safety surveillance study was to evaluate the safety profile of amphoB in a cohort of hospitalized patients who were on the drug for suspected mucormycosis. MATERIALS AND METHODS: All suspected adverse drug reactions (ADRs) in hospitalized mucormycosis patients who had received amphoB were analyzed. The nature, severity, outcome of the ADRs were recorded and analyzed. RESULTS: Of the 77 patients enrolled, 70% had documented history of prior COVID-19 infection. 96% had comorbidities, the most common being diabetes. Majority received conventional amphotericin B deoxycholate formulation. 97% experienced at least one suspected ADR and the median ADR/patient was 3. Out of 214 ADRs, 91 were serious but there were no ADR-related deaths. The most common ADRs were hypokalemia (31.78%), infusion-related reactions (22.43%), and anemia (17.29%). Thirty-three patients had serum potassium <2.5 mEq/L, while 11 had serum magnesium <1.25 mg/dL. Doubling of pretreatment creatinine level was noted in 15 patients. Seventy percent ADRs were of "possible" category as per the World Health Organization Uppsala Monitoring Centre categorization. CONCLUSION: AmphoB deoxycholate use in mucormycosis patients was associated with a high incidence of electrolyte abnormalities and infusion-related reactions. All ADRs subsided with medical management and none were fatal. The safety data generated from this study may be useful in resource-limited settings where the far more expensive liposomal formulation is not being used.


Subject(s)
COVID-19 , Drug-Related Side Effects and Adverse Reactions , Mucormycosis , Humans , Mucormycosis/drug therapy , Mucormycosis/epidemiology , Amphotericin B/adverse effects , Pharmacovigilance , Prospective Studies , Tertiary Care Centers , India/epidemiology
11.
Malar J ; 20(1): 405, 2021 Oct 17.
Article in English | MEDLINE | ID: mdl-34657602

ABSTRACT

BACKGROUND: Despite the widespread use of histidine-rich protein 2 (HRP2)-based rapid diagnostic tests (RDTs), purified native HRP2 antigen is not standardly used in research applications or assessment of RDTs used in the field. METHODS: This report describes the purification of native HRP2 (nHRP2) from the HB3 Plasmodium falciparum culture strain. As this culture strain lacks pfhrp3 from its genome, it is an excellent source of HRP2 protein only and does not produce the closely-related HRP3. The nHRP2 protein was isolated from culture supernatant, infected red blood cells (iRBCs), and whole parasite lysate using nickel-metal chelate chromatography. Biochemical characterization of nHRP2 from HB3 culture was conducted by SDS-PAGE and western blotting, and nHRP2 was assayed by RDT, ELISA, and bead-based immunoassay. RESULTS: Purified nHRP2 was identified by SDS-PAGE and western blot as a - 60 kDa protein that bound anti-HRP-2 monoclonal antibodies. Mouse anti-HRP2 monoclonal antibody was found to produce high optical density readings between dilutions of 1:100 and 1:3,200 by ELISA with assay signal observed up to a 1:200,000 dilution. nHRP2 yield from HB3 culture by bead-based immunoassay revealed that both culture supernatant and iRBC lysate were practical sources of large quantities of this antigen, producing a total yield of 292.4 µg of nHRP2 from two pooled culture preparations. Assessment of nHRP2 recognition by RDTs revealed that Carestart Pf HRP2 and HRP2/pLDH RDTs detected purified nHRP2 when applied at concentrations between 20.6 and 2060 ng/mL, performing within a log-fold dilution of commercially-available recombinant HRP2. The band intensity observed for the nHRP2 dilutions was equivalent to that observed for P. falciparum culture strain dilutions of 3D7 and US06 F Nigeria XII between 12.5 and 1000 parasites/µL. CONCLUSIONS: Purified nHRP2 could be a valuable reagent for laboratory applications as well as assessment of new and existing RDTs prior to their use in clinical settings. These results establish that it is possible to extract microgram quantities of the native HRP2 antigen from HB3 culture and that this purified protein is well recognized by existing monoclonal antibody lines and RDTs.


Subject(s)
Antigens, Protozoan/isolation & purification , Erythrocytes/chemistry , Erythrocytes/parasitology , Malaria, Falciparum/diagnosis , Plasmodium falciparum/chemistry , Protozoan Proteins/isolation & purification , Antigens, Protozoan/immunology , Blotting, Western , Electrophoresis, Polyacrylamide Gel , Enzyme-Linked Immunosorbent Assay , Humans , Immunoassay , Microspheres , Protozoan Proteins/immunology , Quality Control , Time Factors
12.
Noncoding RNA Res ; 5(4): 191-200, 2020 Dec.
Article in English | MEDLINE | ID: mdl-33163736

ABSTRACT

Rice (Oryza sativa L.) is one of the most important cereal crops for one third of the world population. However, the grain quality as well as yield of rice is severely affected by various abiotic stresses. Environmental stresses affect the expression of various microRNAs (miRNAs) which in turn negatively regulate gene expression at the post-transcriptional level either by degrading the target mRNA genes or suppressing translation in plants. Plant homeo-domain (PHD) finger proteins are known to be involved in the plant response to salinity stress. In the present study, we identified 44 putative OsPHD finger genes in Oryza sativa Indica, using Ensembl Plants Database. Using computational approach, potential miRNAs that target OsPHD finger genes were identified. Out of the 44 OsPHD finger genes only three OsPHD finger genes i.e., OsPHD2, OsPHD35 and OsPHD11, were found to be targeted by five newly identified putative miRNAs i.e., ath-miRf10010-akr, ath-miRf10110-akr, osa-miR1857-3p, osa-miRf10863-akr, and osa-miRf11806-akr. This is the first report of these five identified miRNAs on targeting PHD finger in Oryza sativa Indica. Further, expression analysis of 44 PHD finger genes under salinity was also performed using quantitative Real-Time PCR. The expression profile of 8 genes were found to be differentially regulated, among them two genes were significantly up regulated i.e., OsPHD6 and OsPHD12. In silico protein-protein interaction analysis using STRING database showed interaction of the OsPHD finger proteins with other protein partners that are directly or indirectly involved in development and abiotic stress tolerance.

13.
Noncoding RNA Res ; 5(4): 167-177, 2020 Dec.
Article in English | MEDLINE | ID: mdl-33024905

ABSTRACT

Several biotic (bacterial and viral pathogenesis) and abiotic stress factors like salt, drought, cold, and extreme temperatures significantly reduce crop productivity and grain quality throughout the world. MicroRNAs (miRNAs) are small (~22 nucleotides) non-coding endogenous RNA molecules which negatively regulate gene expression at the post-transcriptional level either by degrading the target protein-coding mRNA genes or suppressing translation in plants. Dirigent (DIR) gene protein plays a crucial role as they are involved to dictate the stereochemistry of a compound synthesized by other enzymes as well as in lignifications against biotic and abiotic stress. In plants, several miRNAs, as well as their targets, are known to regulate stress response but systematic identification of the same is limited. The present work has been designed for in silico identification of miRNAs against a total of sixty-one DIR genes in Oryza sativa Indica followed by target prediction of identified miRNAs through the computational approach and thereafter validation of potential miRNAs in rice genotypes. We systematically identified 3 miRNA and their respective DIR specific target gene in Oryza sativa Indica. The expression of these three miRNAs and their respective DIR specific targets were validated in rice seedlings subjected to five different abiotic stress conditions (heavy metal, high temperature, low temperature, salinity and drought) by quantitative Real-Time PCR (qRT-PCR). Expression analysis indicated that miRNA under stress conditions regulates the gene expression of the DIR gene in rice. To the best of our knowledge this is this is the first report in any organism showing the expression of ath-miRf10317-akr, and osamiRf10761-akr miRNAs in response to various abiotic stresses.

14.
Opt Lett ; 44(9): 2161-2164, 2019 May 01.
Article in English | MEDLINE | ID: mdl-31042173

ABSTRACT

In this Letter, experimental observation of dissipative rogue waves (DRWs) due to spectral filtering induced pulse instabilities in a mode-locked ytterbium (Yb) fiber laser has been presented. A semiconductor saturable absorber mirror was used to mode-lock the linear cavity laser and a chirped fiber Bragg grating (CFBG) was used for dispersion management, which also acted as a spectral filter and output coupler. Under stable conditions, the cavity delivered dispersion managed dissipative solitons of 447 fs duration and 0.69 nJ pulse energy at 10.19 MHz repetition rate with uniform intensity distribution over a long time span. As the spectral width increased with pump power, random intensity fluctuations were observed in the pulse train due to the filtering effect of the CFBG. Employing a dispersive Fourier transform by stretching the output pulse train in time allowed the existence of DRWs more than 4 times stronger than the significant wave height to be observed. Further increments of pump power led to a stable multi-pulsing state.

15.
Mov Disord Clin Pract ; 5(1): 39-46, 2018.
Article in English | MEDLINE | ID: mdl-30363072

ABSTRACT

https://onlinelibrary.wiley.com/page/journal/23301619/homepage/mdc312551-sup-v001_1.htm. BACKGROUND: Spinocerebellar ataxia type 12 (SCA12) is a rare form of an autosomal-dominant ataxic disorder associated with an expansion of CAG repeat length. Here, we present a large case series of patients with SCA12 and describe a wide range of typical and rare symptoms. METHODS: Twenty-one consecutive patients with genetically proven SCA12 underwent detailed neurological examination. We assessed clinical characteristics using validated rating scales for evaluating motor features in SCA. Nonmotor symptoms and quality of life were assessed using appropriate, validated scales. Correlations of CAG repeat length with both severity score and age of onset were explored. RESULTS: The mean age of onset was 51 years, and most patients were descendants of a single, endogamous Indian community (Agarwal). Tremor was the most common initial presenting symptom (90%). Hand dystonia was present in 14 of 21 patients, and most patients in the cohort presented with gait disturbance. Neuropsychiatric manifestations were common coexisting features. The CAG repeat length was significantly correlated (r = -0.760; P = 0.0001) with early age of onset, but not with disease severity. Tremor affected the quality of life in 18 of 21 patients, because they had difficulty in handling liquids. CONCLUSIONS: Tremor was the most common, nonataxic symptom at initial presentation in patients with SCA12. Proximal upper limb tremor, typically with high amplitude and low frequency, can raise a strong diagnostic suspicion. Associated hand dystonia was a common coexisting motor feature. Various nonmotor features were also observed in several cases which require therapeutic attention.

16.
Appl Opt ; 57(5): 1225-1230, 2018 Feb 10.
Article in English | MEDLINE | ID: mdl-29469868

ABSTRACT

In this paper, we propose an all-normal-dispersion ytterbium-fiber laser with a novel ring cavity architecture having two nonlinear amplifying loop mirrors (NALM) as saturable absorbers, capable of delivering distinctly different pulses with adjustable features. By optimizing the loop lengths of the individual NALMs, the cavity can be operated to deliver Q-switched mode-locked (Q-ML) pulse bunches with adjustable repetition rates, mode-locked pulses in dissipative soliton resonance (DSR) regime or noise-like pulse (NLP) regime with tunable pulse width. The DSR pulses exhibit characteristic narrowband spectrum, while the NLPs exhibit large broadband spectrum. The operation regime of the laser can be controlled by adjusting the amplifier pump powers and the polarization controllers. To the best of the authors' knowledge, this is the first demonstration of a single mode-locked cavity where narrowband DSR pulses and broadband NLPs alongside Q-ML pulse bunches can be selectively generated by employing two NALMs.

17.
Opt Lett ; 42(13): 2471-2474, 2017 Jul 01.
Article in English | MEDLINE | ID: mdl-28957262

ABSTRACT

A dissipative soliton resonance (DSR) mode-locked Er:Yb fiber laser has been used to pump a thulium fiber laser to generate gain-switched pulses at high repetition rates. Here 412 ns long DSR pulses with a center wavelength of around 1.56 µm at a repetition rate of 410 kHz have been fed to a thulium fiber laser, resulting in generation of gain-switched pulses at 1.94 µm. The minimum pulse width achieved was 256 ns with an average power of 4.6 W at 66% slope efficiency. Gain-switched pulses at 520 kHz and 750 kHz were generated through changing the pump pulse repetition rate by modifying the DSR cavity. To the best of our knowledge, this is the first demonstration of a high repetition rate gain-switched thulium fiber laser pumped by a DSR mode-locked fiber laser. As DSR pulses can be generated with high seed average power and energy independent of the operating wavelength regime as well as mode-locking technique, the proposed method can be applied to generate gain-switched pulses at high repetition rates and various wavelengths without the need of any optical or electrical modulators.

18.
J Clin Diagn Res ; 11(6): FC01-FC04, 2017 Jun.
Article in English | MEDLINE | ID: mdl-28764189

ABSTRACT

INTRODUCTION: Acute Otitis Media (AOM) is one of the frequently diagnosed diseases in children below two years. Amoxicillin-clavulanate potassium is the first line drug in treatment of Paediatric AOM (PAOM). Cefpodoxime has good antimicrobial activity against various types of microorganisms that include causative microorganisms of PAOM. AIM: To compare the efficacy and safety of cefpodoxime and amoxicillin-clavulanate potassium for the treatment of PAOM in children below two years. MATERIALS AND METHODS: A prospective longitudinal study was conducted on children diagnosed with PAOM. Thirty-six children were included in the study: 17 in the Group A (amoxicillin-clavulanate potassium) and 19 in the Group B (cefpodoxime). Primary outcome of this study was clinical success rate at day 10 visit and secondary outcome was incidence of Adverse Events (AEs). RESULTS: The clinical success rates were 93.8% in Group A and 88.2 % in Group B. These rates are comparable and no statistically significant difference was observed between the groups. Few mild and self-limiting AEs were observed and both the drugs were well tolerated. CONCLUSION: The results of this prospective study showed that a 10-day course of cefpodoxime is therapeutically comparable to amoxicillin-clavulanate potassium in terms of both efficacy and safety for the treatment of PAOM in children below two years.

19.
Trop Doct ; 45(2): 148-50, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25601890

ABSTRACT

We report a widely disseminated, disfiguring facial molluscum contagiosum (MC) as a presenting complaint in an 11-year-old girl secondary to human immune-deficiency virus infection. A biopsy specimen demonstrated lobulated epidermal growth consisting of keratinocytes with large intracytoplasmic eosinophilic inclusion bodies. The patient was treated with highly active anti-retroviral therapy (HAART). The extent of MC in our patient was remarkable and subsequently improved dramatically after starting HAART. Normally MC does not similarly respond in patients with AIDS.


Subject(s)
HIV Infections/diagnosis , Molluscum Contagiosum/diagnosis , Antiretroviral Therapy, Highly Active , Child , Diagnosis, Differential , Face/pathology , Female , HIV Infections/complications , HIV Infections/drug therapy , Humans , Molluscum Contagiosum/complications , Molluscum Contagiosum/drug therapy
20.
J Child Neurol ; 30(8): 1070-4, 2015 Jul.
Article in English | MEDLINE | ID: mdl-25117416

ABSTRACT

A 10-year-old girl presented with poorly controlled epilepsy. On evaluation, she had microcephaly, neuro-cutaneous stigmata of tuberous sclerosis complex, profound mental retardation, and spastic hemiparesis. Computed tomography (CT) revealed a calcified subependymal nodule and extensive left gyral calcification of the temporal, parietal, and occipital regions with unilateral cerebral atrophy, radiologic features usually seen in Sturge Weber syndrome. Magnetic resonance imaging (MRI) revealed absence of tubers, enlarged choroid plexus, or leptomeningeal angiomas, thus excluding type 3 Sturge Weber syndrome. The genotype was a heterozygous mutation in exon 18 of the tuberous sclerosis type 1 gene (c.2293C>T p.Q765X). A comparison of previously reported 7 cases of Sturge Weber syndrome and tuberous sclerosis complex was made. This revealed 4 actual double phakomatoses (clinical, radiologic, or genetic phenotypes) and 3 cases with clinical phenotype of tuberous sclerosis and gyral calcifications within tubers simulating the radiologic picture of Sturge Weber syndrome.


Subject(s)
Calcinosis/etiology , Sturge-Weber Syndrome/etiology , Tuberous Sclerosis/complications , Child , Female , Humans , Magnetic Resonance Imaging , Tomography, X-Ray Computed
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