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1.
Dalton Trans ; 53(3): 898-902, 2024 Jan 16.
Article in English | MEDLINE | ID: mdl-38167683

ABSTRACT

We report the electrochemistry of Al3+ ion storage in copper tetrathiovanadate (Cu3VS4) in an aqueous electrolyte for the first time. It is found that Cu3VS4 could deliver an initial discharge capacity of 111 mA h g-1 at a current rate of 0.5 A g-1 and 77 mA h g-1 up to the 300th cycle at 2 A g-1 along with an excellent rate capability. The better electrochemical performance may be attributed to the high theoretical capacity of sulfur and the superior conductivity of copper which allows facile Al3+ ion diffusion in Cu3VS4. The electrochemical mechanism of Al3+ ion storage is also illustrated.

2.
Phys Chem Chem Phys ; 25(36): 24298-24302, 2023 Sep 20.
Article in English | MEDLINE | ID: mdl-37695725

ABSTRACT

Herein, reversible K+ ion insertion into graphite in an aqueous electrolyte is illustrated. It is shown that more facile diffusion of K+ ions is possible in natural graphite than in pyrolytic graphite.

3.
Phys Chem Chem Phys ; 25(20): 13833-13837, 2023 May 24.
Article in English | MEDLINE | ID: mdl-37162519

ABSTRACT

In this work, we report the electrochemical reactivity of MoTe2 for various metal ions with special emphasis on Al3+ ion storage in aqueous electrolytes for the first time. A stable discharge capacity of 100 mA h g-1 over 250 cycles at a current density of 1 Ag-1 could be obtained for the Al3+ ion, whereas inferior storage capacities were shown for other metal ions.

4.
Phys Chem Chem Phys ; 23(35): 19150-19154, 2021 Sep 15.
Article in English | MEDLINE | ID: mdl-34486638

ABSTRACT

Herein, we report the possibility of electrochemical Al3+ ion insertion in LiMn2O4 in aqueous electrolytes. LiMn2O4 exhibits a discharge potential plateau of 1.5 V and a discharge capacity of 65 mA h g-1 is achieved at a current rate of 800 mA g-1 at the 75th cycle with the pre-addition of low-valence Mn ions in an aqueous AlCl3 electrolyte.

5.
Neurol India ; 69(2): 461-465, 2021.
Article in English | MEDLINE | ID: mdl-33904476

ABSTRACT

BACKGROUND: Parkinson's disease (PD) is a multifaceted illness affecting ~ 0.3% of the world population. The genetic complexity of PD has not been, fully elucidated. Several studies suggest that mitochondrial DNA variants are associated with PD. OBJECTIVE: Here, we have explored the possibility of genetic association between mitochondrial haplogroups as well as three independent SNPs with PD in a representative east Indian population. METHODS AND MATERIAL: The Asian mtDNA haplogroups: M, N, R, B, D, M7, and 3 other SNPs: 4336 T/C, 9055 G/A, 13708 G/A were genotyped in 100 sporadic PD patients and 100 matched controls via conventional PCR-RFLP-sequencing approach. RESULTS: The distribution of mtDNA haplogroups, as well as 3 single polymorphisms, did not show any significant differences (P > 0.05) between patients and controls. CONCLUSION: This is the first of its kind of study from India that suggests no association of selected mitochondrial DNA variations with PD.


Subject(s)
DNA, Mitochondrial , Parkinson Disease , Asian People , DNA, Mitochondrial/genetics , Genotype , Haplotypes , Humans , India , Parkinson Disease/genetics , Polymorphism, Single Nucleotide/genetics
6.
Neurosci Lett ; 751: 135816, 2021 04 23.
Article in English | MEDLINE | ID: mdl-33711404

ABSTRACT

INTRODUCTION: GBA mutations have been reported in PD, PDD and DLB - but not associated with cognitive impairment for example in PSP, AD or MSA. However, frequencies of GBA mutations are ethnicity dependent. The present study aims to identify commonly reported GBA mutations (mostly from Asia), among eastern Indian patients with neurodegenerative disorders. METHODS: The patient cohort consisting of 198 classical PD cases, 136 PD cases with cognitive impairment, 184 cases with Parkinson Plus syndrome, 46 AD and 241 unrelated controls, from eastern India. Subjects were analyzed for IVS2 + 1A > G, p.Arg120Trp, p.His255Gln, p.Arg257Gln, p.Glu326Lys, p.Asn370Ser, p.Asp409His, p.Leu444Pro, & RecNciI by PCR-RFLP techniques and confirmed by Sanger sequencing method. RESULTS: We have identified only p.Leu444Pro variant among nine cases; three PDD, one DLB, two PD, two PSP and one AD patients in heterozygous condition. The highest frequency for p.Leu444Pro variant was found among PDD subgroup (3.95 %, P = 0.0134). An overall significant overrepresentation of positive family history (P = 0.000049), impaired recent memory (P = 0.0123) was observed among p.Leu444Pro carriers. Further, subgroup analysis for PD, PD-MCI and PDD, revealed statistically significant higher frequency of early age at onset (P = 0.0455), positive family history (P = 0.0025), higher UPDRS III score (off state) (P = 0.006), advanced H&Y stage (P = 0.045) and anxious behaviour (P = 0.0124) among p.Leu444Pro positive patients. CONCLUSION: The p.Leu444Pro mutation of GBA was found in patients with PD, PDD, DLB, PSP and AD. An Overall higher frequency of positive family history and impaired recent memory are significantly associated with for p.Leu444Pro carriers from eastern India. Our study also ascertains contribution of p.Leu444Pro to an earlier onset of PD, PD-MCI and PDD, higher UPDRS III score (off state) against positive family history background. Furthermore, taking into consideration other Indian studies, we can conclude that p.Leu444Pro mutation plays a limited role in PD and other neurodegenerative disorders.


Subject(s)
Dementia/genetics , Glucosylceramidase/genetics , Mutation, Missense , Parkinsonian Disorders/genetics , Adult , Aged , Female , Gene Frequency , Humans , India , Male , Middle Aged
7.
Indian J Med Res ; 151(6): 592-597, 2020 06.
Article in English | MEDLINE | ID: mdl-32719233

ABSTRACT

Background & objectives: Parkinsonian disorder, including Parkinson's disease (PD), is an aetiologically complex neurodegenerative disorder. Mutations in leucine-rich repeat kinase 2 (LRRK2) gene have been implicated in an autosomal dominant form of PD with variable penetrance. The identification of a common LRRK2 variant (p.Gly2019Ser) in dementia with Lewy bodies indicated its potential role in Parkinsonian disorder. The current study was aimed to identify the p.Gly2019Ser variant in Indian patients with Parkinsonian disorder. Methods: The patient group consisting of 412 classical PD patients, 107 PD patients with cognitive impairment, 107 patients with Parkinson plus syndrome and 200 unrelated controls were recruited from eastern part of India. The allele representing p.Gly2019Ser variant was screened by polymerase chain reaction followed by restriction fragment length polymorphism analysis. Results: The p.Gly2019Ser variant was identified in an East Indian young-onset female PD patient in a heterozygous state having several motor and autonomic problems without disturbed cognition. Her younger brother, sister and elder son harbouring the same mutation were asymptomatic carriers for the variant. However, the influence of DNM3 on decreased disease onset in this family was not clear. Interpretation & conclusions: Identification of the p.Gly2019Ser variant in only one patient among a large number of Indian patients (n=626) with Parkinsonian disorder in our study suggests a limited role of the LRRK2 variant towards disease pathogenesis.


Subject(s)
Leucine-Rich Repeat Serine-Threonine Protein Kinase-2/genetics , Parkinson Disease , Adult , Female , Genetic Predisposition to Disease , History, 16th Century , Humans , India/epidemiology , Male , Middle Aged , Mutation , Parkinson Disease/epidemiology , Parkinson Disease/genetics , Penetrance
8.
Neuromolecular Med ; 21(3): 287-294, 2019 09.
Article in English | MEDLINE | ID: mdl-31134487

ABSTRACT

Parkinson's disease (PD) is a progressive neurodegenerative disease with complex etiology. Both genetic and environmental factors play significant role. Apart from candidate genes, some modifier genes have been reported to be associated with the altered risk of PD. Previous studies have identified Apolipoprotein E (APOE), Cathepsin D (CTSD), and Brain-Derived Neurotrophic Factor (BDNF) as key players of neurodegenerative pathways with their variants associated with different neurodegenerative diseases. Hence, this study aims to identify the potential role of these modifier genes in the pathogenesis of PD among Eastern Indian PD patients. A case-control study was performed using 302 clinically diagnosed PD patients and 304 ethnically matched controls. Promoter SNPs of APOE (rs449647, rs405509) and BDNF (rs56164415), and coding SNPs of APOE (rs429358, rs7412 resulting in ε2, ε3, and ε4 alleles), CTSD (rs17571), and BDNF (rs6265) were analyzed by PCR-RFLP and bidirectional sequencing. The effect of rs56164415 on BDNF expression was characterized by Luciferase assay. APOEε4 allele was significantly overrepresented (p value = 0.0003) among PD patients, whereas ε3 allele was predominant in the control population. The promoter haplotype (A-rs449647, G-rs405509) of APOE was preponderant among female PD patients posing risk. No association was found for CTSD polymorphism. The 'T/T' genotype of BDNF rs56164415 was overrepresented (p-value = 0.02) among early onset PD patients. Expression of BDNF for the 'T/T' variant was significantly lower (p-value = 0.012) than the 'C/C' variant, suggesting a possible role in PD pathogenesis. This study suggests that APOE and BDNF may serve as modifier loci among eastern Indian PD patients.


Subject(s)
Apolipoproteins E/physiology , Brain-Derived Neurotrophic Factor/physiology , Cathepsin D/physiology , Parkinson Disease/genetics , Adolescent , Adult , Age of Onset , Aged , Alleles , Case-Control Studies , Child , Female , Gene Frequency , Genotype , Humans , India/epidemiology , Male , Middle Aged , Parkinson Disease/epidemiology , Parkinson Disease/metabolism , Polymorphism, Single Nucleotide , Promoter Regions, Genetic , Protein Isoforms/genetics , Protein Isoforms/physiology , Young Adult
9.
Neurol India ; 67(2): 433-438, 2019.
Article in English | MEDLINE | ID: mdl-31085855

ABSTRACT

BACKGROUND: Frontal assessment battery (FAB) was devised as a specific study design to assess frontal lobe dysfunction. Since Parkinson's disease (PD) is often associated with cognitive and other higher mental function complications, FAB test has been carried out by a number of workers to assess the integrity of the frontal lobe. On the other hand, the other frequently conducted test, performed in order to evaluate the mental status, is the Mini Mental State examination of Folstein (MMSE), but its reliability has been questioned in PD, since it does not assess the functions of the frontal lobe alone. MATERIAL AND METHODS: The present study was undertaken in order to assess the suitability of application of the FAB test in Indian patients and to perform its comparative analysis with the MMSE scale. RESULTS AND CONCLUSIONS: It was observed that the FAB test correlated with the age and the level of education of the patient. The results also correlated with that of the MMSE study, in spite of the fact that the latter is not considered to be a test which can assess exclusively the status of the frontal lobe. To the best of our knowledge, this is first study undertaken in India in this regard.


Subject(s)
Cognition Disorders/surgery , Frontal Lobe/surgery , Parkinson Disease/surgery , Aged , Cognition Disorders/diagnosis , Female , Humans , India , Male , Middle Aged , Neuropsychological Tests , Parkinson Disease/complications , Parkinson Disease/diagnosis , Reproducibility of Results , Treatment Outcome
10.
Dalton Trans ; 48(19): 6337-6340, 2019 May 15.
Article in English | MEDLINE | ID: mdl-30984968

ABSTRACT

Can electrochemical Al3+ ions be reversibly intercalated in tungsten trioxide (WO3) in aqueous electrolytes? Here, we address this particular question and demystify that Al3+ ions can indeed be intercalated and deintercalated in WO3 in certain Al3+ ion conducting aqueous electrolytes.

11.
Neurosci Lett ; 675: 68-73, 2018 05 14.
Article in English | MEDLINE | ID: mdl-29604408

ABSTRACT

BACKGROUND: Parkinson's disease (PD) is the second most common neurodegenerative disease and has a complex etiology. Single nucleotide polymorphisms in the 3'-untranslated region of Fibroblast growth factor 20 (FGF 20) have been reported to be associated with PD; however, the results are controversial. Although FGF20 enhances the survival of dopaminergic neurons, it may also result in PD susceptibility by altering alpha-synuclein expression. MATERIALS AND METHODS: To identify and characterize genetic risk variants in FGF 20 in Eastern Indian PD patients, 2 SNPs of FGF 20 (rs1721100 and rs2720208) were genotyped in 336 PD cases and 313 ethnically matched controls by PCR-RFLP. RESULTS: We observed statistically significant differences in genotypic and allelic frequencies of rs1721100 between PD cases and controls but not for rs12720208. Haplotype G-C showed a significant protective effect against PD. A functional assay revealed that the risk allele C at rs1721100 has little or no effect on relative luciferase activity from a reporter construct in the presence of miR-3189-3p, whereas allele G results in significant dose-dependent reduction. CONCLUSION: Our results suggest that FGF 20 is a susceptibility gene for PD in Eastern Indians.


Subject(s)
Fibroblast Growth Factors/genetics , Parkinson Disease/genetics , 3' Untranslated Regions , Adult , Female , Gene Frequency , Genetic Predisposition to Disease , Genetic Variation , Haplotypes , Humans , India , Male , Middle Aged , Polymorphism, Single Nucleotide , Risk Factors
12.
Angew Chem Int Ed Engl ; 57(51): 16606-16617, 2018 Dec 17.
Article in English | MEDLINE | ID: mdl-29566301

ABSTRACT

The pairing of an aluminum anode with a cathode of high energy and power density determines the future of aluminum-ion battery technology. The question is-"Is there any suitable cathode material which is capable of storing sufficiently large amount of trivalent aluminum-ions at relatively higher operating potential?". Graphene emerges to be a fitting answer. Graphene emerged in the research arena of aluminum-ion battery merely three years ago. However, research progress in this front has since been tremendous. Outperforming all other known cathode materials, several remarkable breakthroughs have been made with graphene, in offering extraordinary energy density, power density, cycle life, thermal stability, safety and flexibility. The future of the Al-graphene couple is indeed bright. This Minireview highlights the electrochemical performances, advantages and challenges of using graphene as the cathode in aluminum-ion batteries in conjugation with chloroaluminate based electrolytes. Additionally, the complex mechanism of charge storage in graphene is also elaborated.

13.
Ann Hum Genet ; 82(2): 53-59, 2018 03.
Article in English | MEDLINE | ID: mdl-29059476

ABSTRACT

Wilson disease (WD) is an autosomal-recessive disorder caused by mutations in the ATP7B gene leading to abnormal copper deposition in liver and brain. WD manifests diverse neurological and hepatic phenotypes and different age of onset, even among the siblings, with same mutational background suggesting complex nature of the disease and involvement of other candidate genes. In that context, Apolipoprotein E (APOE) and Prion Protein (PRNP) have been proposed to be potential candidates for modifying the WD phenotype and age of onset. This study aims to identify the contribution of APOE and PRNP polymorphisms on the variable phenotypic expression of Indian WD patients. A total of 171 WD patients and 291 controls from Indian population were included in this study. Two APOE cSNPs (rs429358 and rs7412) resulting in three isoforms and M129V (rs1799990) polymorphism of PRNP were examined for their association with WD and its clinical phenotypes. The APOE ԑ4 allele was found to be significantly overrepresented in WD patients compared to controls. However, the frequency of the APOE ԑ3 allele and ԑ3/ԑ3 genotype was significantly higher in WD patients without cognitive behavior impairment compared to the ones with the impairment. On the contrary, the PRNP allele representing Val129 was found to be present in higher proportion in WD patients with cognitive behavioral decline. Our data suggest that the APOE ԑ4 allele could act as a potential risk for the pathogenesis of WD. Also, APOE and PRNP might contribute toward the cognitive behavioral decline in a section of WD patients.


Subject(s)
Apolipoproteins E/genetics , Hepatolenticular Degeneration/genetics , Polymorphism, Single Nucleotide , Adolescent , Adult , Alleles , Case-Control Studies , Child , Child, Preschool , Female , Humans , India , Male , Phenotype , Prion Proteins/genetics , Young Adult
14.
Neurol India ; 65(6): 1280-1288, 2017.
Article in English | MEDLINE | ID: mdl-29133701

ABSTRACT

BACKGROUND: Headache is common in communities; however, epidemiological research regarding its prevalence is infrequent in India. AIM: We planned to study the prevalence of migraine, its disease burden, and the associated risk factors. SETTING AND DESIGN: This is an urban community study conducted in Kolkata with a cross-sectional and nested case-control design. MATERIALS AND METHODS: The criteria to study headache among a representative sample (aged 20-50 years) was based on the International Classification of Headache Disorders-II. Sex- and age-matched controls without headache were evaluated for putative risk factors. The disease burden was measured as disability adjusted life years (DALY). RESULTS: Screening of 2421 individuals revealed that the 1-year prevalence of migraine was 14.12%. Education, environmental exposure, travel, and oral contraceptives determine approximately 75% of the underlying risks. DALY showed maximum burden among women in the age range of between 30 and 34 years. CONCLUSION: The community-based prevalence of migraine in India is similar to that observed in other countries except Africa. The burden was maximum among women. The risk factors responsible for migraine should be addressed and institution of public health measures are warranted.


Subject(s)
Headache/epidemiology , Headache/therapy , Migraine Disorders/epidemiology , Migraine Disorders/therapy , Adult , Case-Control Studies , Cross-Sectional Studies , Female , Humans , India/epidemiology , Male , Middle Aged , Prevalence , Risk Factors , Young Adult
15.
Int Rev Neurobiol ; 134: 1443-1459, 2017.
Article in English | MEDLINE | ID: mdl-28805579

ABSTRACT

Wilson disease (WD) is an autosomal genetic disorder characterized by excessive copper deposition initially in liver (hepatic variant) followed by brain (neuropsychiatric variant) and other organs such as cornea and kidney due to defect in biliary copper excretion. Predominant presentations of neuropsychiatric variant are extrapyramidal motor dysfunctions such as dystonias, Parkinsonism, choreoathetosis, tremor, and ataxias. Nonmotor symptoms (NMS) can appear before clinical disease expression and during ongoing disease process. NMS may cause confusion and delay in clinical diagnosis. In the early stage, presence of asymptomatic or symptomatic evidence of acute or chronic liver disease with or without KF ring in young subjects against the background of family history of liver disease may be indicative of underlying WD. In WD, common NMS are personality disorders, mood changes, psychosis, cognitive abnormalities, sleep disorders, and autonomic disturbances besides few systemic dysfunctions. Cognitive changes can be diagnosed by neuropsychological assessment, MRI, and SPECT study of brain. Nonmotor manifestations can be managed by metal chelator, antipsychotic agents, mood stabilizers, rarely electroconvulsive therapy, and occasional hepatic transplantation.


Subject(s)
Brain/diagnostic imaging , Hepatolenticular Degeneration/diagnostic imaging , Hepatolenticular Degeneration/therapy , Liver/diagnostic imaging , Brain/metabolism , Chelating Agents/therapeutic use , Copper/metabolism , Hepatolenticular Degeneration/metabolism , Humans , Liver/metabolism , Mental Disorders/diagnostic imaging , Mental Disorders/metabolism , Mental Disorders/therapy , Mood Disorders/diagnostic imaging , Mood Disorders/metabolism , Mood Disorders/therapy
16.
J Nanosci Nanotechnol ; 16(4): 4131-5, 2016 Apr.
Article in English | MEDLINE | ID: mdl-27451776

ABSTRACT

Tungsten trioxide (WO3) is investigated for the first time as an anode material for sodium-ion batteries. Pristine WO3 displays a discharge potential plateau at 1 V and exhibits a 1st discharge cycle sodium storage capacity of 640 mAh g-1. Electronic wiring of WO3 with graphene oxide (GO, 1% by weight) led to a significant increase in the storage capacity and cyclability of WO3. As a result, the discharge capacity of 1% GO-WO3 is enhanced to 927 mAh g-1 in the 1st discharge cycle. The electrochemical intercalation of Na in to WO3 and (1%) GO-WO3 as obtained from galvanostatic charge/discharge cycling is also supported by cyclic voltammetry.

17.
Chem Commun (Camb) ; 52(7): 1428-31, 2016 Jan 25.
Article in English | MEDLINE | ID: mdl-26645737

ABSTRACT

We report here the synergistic effect of graphene and diglyme electrolyte in significantly improving the sodium insertion electrochemistry of nanocrystalline anatase TiO2.

18.
Parkinsonism Relat Disord ; 20(1): 75-81, 2014 Jan.
Article in English | MEDLINE | ID: mdl-24094725

ABSTRACT

Wilson disease (WD) is caused by defects in ATP7B gene due to impairment of normal function of the copper transporting P-type ATPase. This study describes a comprehensive genetic analysis of 199 Indian WD patients including mutations detected in our previous studies, undertakes functional assessment of the nucleotide variants in ATP7B promoter and correlates genotype with disease phenotype. The patient cohort harbors a total of 10 common and 48 rare mutations in the coding region of ATP7B including 21 novel changes. The common mutations represent 74% of characterized coding mutant alleles with p.C271X (63/260) and p.G1101R (7/31) being the most prevalent in eastern and western Indian patients, respectively. The mutation spectrum between east and west is mostly different with only three mutations (p.G1061E, p.N1270S and p.A1049A-fs) being shared between both the groups. Eight novel and 10 reported variants have been detected in the promoter and non-coding regions (5' and 3'UTRs) of ATP7B. Promoter reporter assay demonstrated that 3 novel variants and 5 reported polymorphisms alter the gene expression to a considerable extent; hence might play important role in ATP7B gene regulation. We devised the neurological involvement score to capture the spectrum of neurological involvement in WD patients. By utilizing the age at onset, neurological involvement score and ATP7B mutation background, we generated a genotype-phenotype matrix that could be effectively used to depict the phenotypic spectra of WD affected individuals and serve as a platform to identify prospective "outliers" to be investigated for their remarkable phenotypic divergence.


Subject(s)
Adenosine Triphosphatases/genetics , Cation Transport Proteins/genetics , Hepatolenticular Degeneration/genetics , Adolescent , Child , Copper-Transporting ATPases , DNA Mutational Analysis , Female , Genetic Association Studies , Humans , India , Male , Mutation , Polymerase Chain Reaction , Young Adult
19.
Am J Alzheimers Dis Other Demen ; 28(6): 575-82, 2013 Sep.
Article in English | MEDLINE | ID: mdl-23823144

ABSTRACT

INTRODUCTION: Alzheimer's disease (AD) is characterized by amnesia, though non-memory-cognitive domains like visual are also affected. We planned to study frequency of visual dysfunctions in AD and their relationship with dementia severity. MATERIALS AND METHODS: This study was conducted in the Cognitive clinic of Department of Neurology, Bangur Institute of Neurosciences, Kolkata, between January 2007 and December 2010. 55 patients of AD were evaluated by neurological and neuropsychological assessments and by special tests for visual dysfunctions. RESULTS: Common visual dysfunctions were visuo-constructional (87.3%), visuo-perceptual (63.6%), object agnosia(47.3%), prosopagnosia (45.5%), visual hallucination (27.3%) and simultanagnosia (12.7%). Symptoms of ventral visual pathway dysfunction were more common than that of dorsal pathway. MMSE score and number of visual manifestations had a good correlation. CONCLUSIONS: Visual dysfunctions are common in AD, elicitation of which helps us to understand the cause of disability so that appropriate steps can be taken.


Subject(s)
Agnosia/complications , Alzheimer Disease/complications , Hallucinations/complications , Prosopagnosia/complications , Visual Perception/physiology , Aged , Aged, 80 and over , Agnosia/physiopathology , Alzheimer Disease/physiopathology , Ambulatory Care Facilities , Cross-Sectional Studies , Disability Evaluation , Female , Hallucinations/physiopathology , Humans , India , Male , Middle Aged , Neuropsychological Tests , Prosopagnosia/physiopathology , Visual Pathways/physiopathology
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