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1.
Mitochondrion ; 68: 25-43, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36371073

RESUMO

Genome-wide deregulation contributes to mitochondrial dysfunction and impairment in oxidative phosphorylation (OXPHOS) mechanism resulting in oxidative stress, increased production of reactive oxygen species (ROS) and cell death in individuals with Down syndrome (DS). The cells, which require more energy, such as muscles, brain and heart are greatly affected. Impairment in mitochondrial network has a direct link with patho-mechanism at cellular and systemic levels at the backdrop of generalized metabolic perturbations in individuals with DS. Myriads of clinico-phenotypic features, including intellectual disability, early aging and neurodegeneration, and Alzheimer disease (AD)-related dementia are inevitable in DS-population where mitochondrial dysfunctions play the central role. Collectively, the mitochondrial abnormalities and altered energy metabolism perturbs several signaling pathways, particularly related to neurogenesis, which are directly associated with cognitive development and early onset of AD in individuals with DS. Therefore, therapeutic challenges for amelioration of the mitochondrial defects were perceived to improve the quality of life of the DS population. A number of pharmacologically active natural compounds such as polyphenols, antioxidants and flavonoids have shown convincing outcome for reversal of the dysfunctional mitochondrial network and oxidative metabolism, and improvement in intellectual skill in mouse models of DS and humans with DS.


Assuntos
Doença de Alzheimer , Síndrome de Down , Doenças Mitocondriais , Humanos , Animais , Camundongos , Síndrome de Down/tratamento farmacológico , Qualidade de Vida , Doenças Mitocondriais/metabolismo , Mitocôndrias/metabolismo , Antioxidantes/metabolismo , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo
2.
Environ Sci Pollut Res Int ; 30(1): 1997-2019, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35922599

RESUMO

Immediate assessment of genetic damage in methyl isocyanate (MIC) gas-exposed population in small and heterogeneous samples using diversified study designs and solid-stained metaphases could not depict the actual genetic impact of MIC on accidentally exposed individuals. The outcome of the then large multi-center genetic screening program was not available to the public and scientific community. Also, the routine and regular epidemiological health survey does not capture the genetic and long-term effect of MIC. Therefore, genetic screening was carried out 30 years post disaster during 2015-2017 with a view to screen the present status of chromosomal consequences in lymphocytic cells. Participants were recruited from moderate (34) and severely (78) exposed and unexposed (35) cohorts with their informed consent. Analysis of ~100 mitotic cells and karyotyping of at least 10-15 and all abnormal metaphases detected structural and numerical alterations, including stable and replicable ones. Clonal abnormalities were detected with monosomal and complex karyotypes, trisomy 8, del5q/20q, loss of Y, etc. Among all, X-chromosome was frequently involved in numerical alterations. Structural aberrations appeared higher in the then exposed populations, though abnormalities cannot be linked directly to MIC exposure 30 years post disaster. Collectively, all rearrangements were markedly higher in the severely exposed population. Altogether, the detected abnormalities appeared random and indicated genomic instability, suggesting follow-up at shorter intervals for the individuals detected with clonal aberrations. G-banding has facilitated recognition of chromosomal involvement and their breakpoints and classification of structural rearrangements. The present data has been derived from the 30-year post-disaster genetic screening.


Assuntos
Desastres , Isocianatos , Humanos , Cromossomos , Estilo de Vida , Aberrações Cromossômicas
3.
Artigo em Inglês | MEDLINE | ID: mdl-37442927

RESUMO

Most of the individual and/or amalgamated compounds present in the atmospheric air are not known for their toxicologic potential and impact on human health. The toxicologic strength of methyl isocyanate (MIC) gas was unknown till its accidental leakage that instantly claimed thousands of lives. Cytogenetic study showed increased chromosome aberrations (CA) and sister chromatid exchanges (SCEs) and delayed cell replication index (RI) in a multicentre genetic screening program on gas victims immediate post-disaster. A surveillance study after 30 years displayed reduction in CA compared to the initial status in survivors of the severely and moderately exposed strata. Altogether, cytogenetic damage was significantly predominant in the severely exposed population. Stable and replicable aberrations and chromatid exchanges were detected in both studies, which collectively indicate genetic instability. The variation in individual cytogenetic spectrum from similar exposure status could be the result of inter-individual response to the external factors over 30 years post-disaster. The spectrum of CA detected after 30 years might be the cumulative effect of occupational, environmental and life-style factors at a background of one episode of acute MIC exposure. Had MIC's toxicologic potential was known before, fatality and health effects could have been averted. In vitro assessment of toxicity of tin showed a positive correlation with dose and age of exposure, which was aggravated by smoking. Age has shown a significant effect on CA in the general population. The present report recommends evaluation of toxicity prior to use, and reduction of pollution at source for a maintaining a sustainable environmental context.

4.
Mitochondrion ; 65: 88-101, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35623559

RESUMO

Triplication of genes encoded in human chromosome 21 (HSA21) is responsible for the phenotypes of Down syndrome (DS). The dosage-imbalance of the nuclear genes and the extra-nuclear mitochondrial DNA (mtDNA) jointly contributes to patho-mechanisms in DS. The mitochondrial organelles are the power house of cells for generation of ATP and maintaining cellular calcium and redox homeostasis, and cellular energy-metabolism processes. Each cell contains hundreds to thousands of mitochondria depending on their energy consumption. The dynamic structure of mitochondria is maintained with continuous fission and fusion events, and thus, content of mtDNA and its genetic composition are widely variable among cells. Cells of brain and heart tissues of DS patients and DS-mouse models have demonstrated elevated number but reduced amount of mtDNA due to higher fission process. This mechanism perturbs the oxidative phosphorylation (OXPHOS) and generates more free radicals such as reactive oxygen species (ROS), suggesting contribution of mtDNA in proliferation and protection of cells from endogenous toxic environment and external stressors. Gene-dosage in DS population collectively contributes to mitochondrial dysfunction by lowering energy production and respiratory capacity via the impaired OXPHOS, and damaged redox homeostasis and mitochondrial dynamics in all types of cells in DS. The context is highly complex and affects the functioning of all organs. The effect in brain and heart tissues promotes myriads of neurodegenerative diseases and cardiac complexities in individuals with DS. Crosstalk between trisomic nuclear and mitochondrial genome has been crucial for identification of potential therapeutic targets.


Assuntos
Síndrome de Down , Mitocôndrias , Animais , DNA Mitocondrial/genética , DNA Mitocondrial/metabolismo , Síndrome de Down/genética , Humanos , Camundongos , Mitocôndrias/genética , Mitocôndrias/metabolismo , Dinâmica Mitocondrial/genética , Fosforilação Oxidativa , Espécies Reativas de Oxigênio/metabolismo
5.
J Cancer Res Ther ; 18(3): 760-764, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35900551

RESUMO

Purpose: The chronic myeloid leukemia (CML) is characterized by the presence of t(9;22)(q34;q11) that results in chimerization of BCR and ABL genes on the rearranged chromosome 22 or Philadelphia chromosome (Ph). Imatinib has been established as the first line of therapy for CML; in case of Imatinib failure or resistance, other second or third generation tyrosine kinase inhibitors (TKIs) are considered. However, acquisition of additional clonal abnormalities (ACAs) interferes in management of CML. We described a complex scenario of cytogenetic remission, relapse, response to TKIs and behavior of ACAs in a case of CML. Materials and Methods: Conventional G-banding and FISH cytogenetics, and quantitative PCR studies were conducted in the bone marrow for diagnosis and follow up (FU) of the changes of BCR-ABL gene and ACAs at different time intervals. Results: Ph- chromosome disappeared within 6 months of Imatinib therapy, and re-appeared within a year. Subsequent change of TKI to dasatinib eliminated the Ph+ clone, but established an ACA with trisomy 8 (+8). Further change to Nilotinib, eliminated +8 clone, but re-emergence of Ph+ clone occurred with an ACA with monosomy 7 (-7). Reinstate of Dasatinib eliminated Ph+ and -7 clones, but with gradual reappearance of Ph+ and +8 clones. The patient discontinued FU, though participated in a long term examination. Conclusion: The complexity of ACAs and Ph+ clones needs frequent monitoring with changes of TKI and technologies.


Assuntos
Leucemia Mielogênica Crônica BCR-ABL Positiva , Células Clonais , Dasatinibe/uso terapêutico , Humanos , Mesilato de Imatinib/farmacologia , Mesilato de Imatinib/uso terapêutico , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico
6.
J Natl Med Assoc ; 112(1): 57-73, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31759676

RESUMO

OBJECTIVES: Aging is not just a consequence of wear-and-tear, but it is the inappropriate regenerative mechanism of the stem cells. Aging is directly proportional to increase in health-problems involving all organs and physiological systems - more of non-communicable types. On the other hand, medical advancement and awareness about health-care are increasing the life expectancy, which could outnumber the young generation or the mainstream of work-force gradually. Hence, understanding of disease-prevalence is essential with a view to making necessary medical, environmental and economic arrangements and offering holistic care to the older population. STUDY DESIGN: Records of medical consultancies of outpatient departments (OPD) were retrieved from the hospital database and considered for understanding the disease-prevalence in the geriatric population. METHODS: Over 47000 subjects of 60 years and above were categorized into eight age-groups and analyzed for age-related disease-prevalence in both males and females. RESULTS: Approximately 25% were affected with cardiovascular system followed by 20% with general complication of cold/cough/fever and GI-disorientation. A uniform damage was observed in systems such as gastro-/neuro-/nephro-/ophthalmic and urology in both genders. Males were more prone to cardiac, nephorologic and urologic problems whereas females were more affected with musculo-skeletal problems than men. In general, men were more affected with geriatric diseases. CONCLUSION: Cardiovascular disorder after 60 years onwards could be related to stress for transition from 'income-to-no-income' state and lack of financial and other preparedness. Significant osteoarthritis problem in females is undoubtedly associated with ageing of ovaries. An intensive medical intervention following hospital-admission and outcome will guide for building age-friendly, long-stay and isolated accommodation, which could be considered for low- and middle-income countries as a model for handling geriatric disease burden.


Assuntos
Envelhecimento/fisiologia , Efeitos Psicossociais da Doença , Avaliação Geriátrica , Doenças não Transmissíveis , Idoso , Feminino , Avaliação Geriátrica/métodos , Avaliação Geriátrica/estatística & dados numéricos , Humanos , Índia/epidemiologia , Expectativa de Vida , Masculino , Pessoa de Meia-Idade , Avaliação das Necessidades , Doenças não Transmissíveis/economia , Doenças não Transmissíveis/epidemiologia , Doenças não Transmissíveis/terapia , Fatores Sexuais , Fatores Socioeconômicos
7.
J Pharmacopuncture ; 23(3): 165-172, 2020 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-33072414

RESUMO

OBJECTIVES: In the past few years, herbal medicines have gained popularity over synthetic drugs because of their natural source and minimal side effects which has led to a tremendous growth of phytopharmaceuticals usage. With the development of nanotechnology, it provides alternative approaches to overcome several limitations using nano-formulations. In spite of considerable quantity of antianemic preparations with different iron forms available, currently additives are used and represented in modern pharmaceutical market. Iron deficiency anemia is a major global public health problem which particularly affects pregnant women, children and elderly persons. The situation is complicated because of disadvantages and drug side effects from existing antianemic medicines. There is a great demand for the development of new antianemic preparations. Green synthesis of iron oxide nanoparticles, possess high potential in this field. METHODS: Our study focuses on developing green synthesis of iron oxide nanoparticles (IONPs) of 10-50 nm with spherical shape where different dosages were used -1 mg/kg, 10 mg/kg and 100 mg/kg for exposure in Wistar albino female rats for 28 days. The toxicity was assessed using various parameters such as measurements of the rat body and organ mass, hematology, biochemical evaluation and histopathological examinations. RESULTS: No significant differences were observed in body and organ weights. Hematological indices also indicated no significant differences whereas biochemical factors showed increase in levels of direct bilirubin and globulin of medium as well as high dose and SGPT levels were increased only in high dose. The major organs (heart, kidney and liver) showed histopathological alterations in 10 and 100 mg/kg whereas brain showed only in 100 mg/kg. CONCLUSION: The toxicity of IONPs was found to be more significant when the concentration was increased; however, low doses can be used for further investigation as an antianemic preparation.

8.
Environ Sci Pollut Res Int ; 25(5): 4963-4973, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29204942

RESUMO

Health effects of methyl isocyanate (MIC) exposure were mostly reported on the one-time acute exposure in Bhopal population. Epidemiological survey conducted by the Indian apex body of health research has been reported as Technical Reports, which were lacking in peer review by the expert epidemiologic scientists. The present pilot survey was aimed to measure the health effects 30 years post disaster in MIC-exposed survivors. Questionnaire-based survey has captured every health complaint in 168 individuals and grouped as systemic functions for interpreting the long-term effects of MIC. Key health parameters, including reproductive outcome and respiratory/orthopedic/general morbidity, were prevalent among the severely exposed population compared to control and moderately exposed groups. The collective incidence of diabetes, hypertension, and cancer also was prevalent in the severely exposed group. Ophthalmic morbidity was almost similar in the three groups, rather with higher incidence in the control group, though not statistically significant. Among all health parameters, reproductive, ophthalmic, and respiratory effects were prevalent over others. Although the incidence of health problems has been declined among the survivors, long-term effect is apparent as scars of one-time acute exposure might trigger sequel of long-term effects. Additionally, acquisition of genetic rearrangements, survival of T cell sub-populations, variable latency of chemical effect on DNA nucleosides, nutritional status, occupational exposure, living environment, lifestyle, and overall gene-environment interaction might perturb individual immunity and favor onset of long-term illness in a scenario of background exposure to MIC. However, the exercise should be continued on a larger sample size for drawing a conclusive result on long-term MIC effect on survivors' health.


Assuntos
Vazamento Acidental em Bhopal , Desastres , Exposição Ambiental/efeitos adversos , Indicadores Básicos de Saúde , Isocianatos/toxicidade , Sobreviventes , Feminino , Humanos , Incidência , Índia , Estilo de Vida , Masculino , Pessoa de Meia-Idade , Morbidade , Neoplasias/epidemiologia , Neoplasias/mortalidade , Prevalência , Reprodução/efeitos dos fármacos
9.
Mutat Res ; 809: 32-50, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29684722

RESUMO

Follow-up cytogenetic study was carried out on 145 individuals from areas stratified by Indian Council of Medical Research, for evaluation of the effect of age-at-exposure and its interaction with exposure status on chromosomal aberrations (CA) in blood-lymphocytes. CA was presented as abnormal cell (Abc), aberrations (Abn) and number of aberration/abnormal cell (Abn/Abc), and correlated with age-at-exposure (childhood: <1-10 years; young: 11-26 years; adult: >27 years). Age related increase in abnormalities (Abc, Abn, Abn/Abc) was observed in all exposure strata, except moderately exposed adult-group, which has exhibited lower Abn/Abc than similarly exposed childhood and young age-groups. Elevation of CA was also related to exposure status. Abn/Abc frequency was significantly higher in the severely exposed young and adult groups compared to the controls of the same age. Two-way ANOVA revealed significant abnormalities between the exposed groups; however, interaction of age and exposure was not statistically significant. Significant difference in group-means of Abc and Abn was also observed between adult and childhood in Tukey HSD test. Altogether, a significant interaction of age and MIC-exposure on CA could not be established due to inter-individual variation and lack of baseline information on CA. Significantly higher Abn was observed in people consuming tobacco; however, interaction of lifestyle with additional environmental/occupational exposures during last 30 years against a background exposure to MIC remained un-elucidated. Nevertheless, the study was important for demonstration of the correlation of the current status of CA in circulating lymphocytes with age and exposure status of the MIC-exposed survivors.


Assuntos
Vazamento de Resíduos Químicos , Aberrações Cromossômicas/induzido quimicamente , Desastres , Exposição Ambiental/efeitos adversos , Isocianatos/toxicidade , Adulto , Fatores Etários , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Índia , Lactente , Masculino
10.
J Cancer Res Ther ; 13(2): 381-383, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28643766

RESUMO

Reports on imbalanced HSA21 gene expression and chromosomal rearrangements on leukemogenesis, drug sensitivity, and treatment outcome of leukemia in Down syndrome (DS) are limited. DS has been recognized as one of the most common leukemia-predisposing syndromes with unique clinical features, significant differences in treatment outcome and treatment-related toxicity profiles. Acute myeloid leukemia (AML), especially acute megakaryocytic leukemia, is reported with high cure rates presenting 80%-100% event-free survivals (EFSs); however, acute lymphoid leukemia indicates a worse prognosis in DS patients compared to non-DS children. Complex rearrangements are responsible for poor-to-very poor prognosis in all cases, irrespective of genetic predisposition or type of hematopoietic subunits affected. We report a 2-year-old female DS diagnosed with acute erythroleukemia (French-American-British: AML-M6) with highly complex chromosomal rearrangements in the bone marrow with 39 chromosomes. Parental consanguinity and genetic predisposition might be responsible for origin of multiple clones. Genetic instability and heterogeneity of complex clonal developments might cause poor prognosis. The case is a rare one with acute erythroleukemia in DS patient where too many rearrangements had masked identification of three 21s.


Assuntos
Síndrome de Down/complicações , Leucemia/complicações , Pré-Escolar , Síndrome de Down/genética , Feminino , Humanos , Leucemia/genética
11.
J Cancer Res Ther ; 12(3): 1203-1206, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28054536

RESUMO

Myelodysplastic syndrome (MDS) is a heterogeneous premalignant condition characterized by cytopenia, ineffective hematopoiesis, dysplastic marrow, and risk of progression to acute myeloid leukemia. Cytogenetic abnormalities, including del(3q/5q/7q/11q/12p/20q), monosomy 5/7, trisomy 8/19, i(17q), and -Y, are the indicators of diagnosis and risk stratification. The present case with bicytopenia detected with highly complex chromosome rearrangements with variability in numerical and structural combinations. Chromosome analysis was carried out following unstimulated marrow culture and G-banding. In addition to known MDS-aberrations, der(9p), der(12) dic(12;?19), +15, -18, and ring and marker chromosomes were recorded having, at least, nine abnormal chromosomes/cell. To our knowledge, this is the first case with all MDS-aberrations in one single individual. The case has been discussed in relevance to current MDS research. In the present case, i(17q)/-17, der(12p), del(5q26), del(7q36), and del(20q11) indicate possible alterations in TP53, ETV6, IDH2, EZH2, and SRSF2 genes, which are responsible for pathomechanism, genetic instability, clonal evolution, and advancement of disease condition.


Assuntos
Aberrações Cromossômicas , Síndromes Mielodisplásicas/diagnóstico , Síndromes Mielodisplásicas/genética , Idoso , Bandeamento Cromossômico , Estudos de Associação Genética , Predisposição Genética para Doença , Humanos , Cariotipagem , Mutação
12.
Case Rep Genet ; 2011: 396450, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-23074675

RESUMO

Unbalanced chromosomal rearrangements are not common; however, they have a significant clinical expression. The parental balanced translocation produces unbalanced chromosome, which is transmitted to next generation through fertilization of gametes carrying the derivative chromosome. The carriers of balanced rearrangements mostly do not have recognizable phenotypic expression. We report a family comprising of healthy and non-consanguineous young parents and their preemie newborn severely affected with congenital anomalies and systemic disorders. Conventional Gbanding analysis of somatic chromosomes identified a balanced translocation, t(6;10)(p23;q24), in mother and an unbalanced rearrangement, der(6)t(6:10)(p23;q24)mat, in the child. The child has inherited a derivative chromosome 6 with partial deletion of 6(p23-pter) and partial trisomy 10(q24-qter), which has resulted in fusion of genes of two different chromosomes. The prominent phenotypic features of del(6p), including high forehead, flat nasal bridge, agenesis of left ear, atrial septal defect (ASD), craniosynostosis, and growth retardation, are overlapping with specific Axenfeld-Reiger-, Larsen-, and Ritscher-Sinzel/3-C syndromes, however, lacking in ocular anomalies, skeletal laxity, or cerebellar malformation. Therefore, this paper rules out the isolated effect of del(6p23) or trisomy 10(q24) on distinct previously reported syndromes and proposes the combined effect of unbalanced chromosomal alteration.

13.
J Cancer Res Ther ; 3(2): 124-6, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17998739

RESUMO

Chromosomal analysis was carried out in bone marrow sample of an 11-year-old girl suspected of myeloproliferative disorder. Conventional G-banding study detected a complex three-way translocation involving 7, 9 and 22, which has resulted in the formation of a variant Philadelphia chromosome causing rearrangement of abl and bcr genes in 87% cells. Fluorescence in situ hybridization (FISH) confirmed the fusion of bcr-abl oncogene. Thus the bone marrow karyotype was observed as 46,XX (13%)/46,XX,t(7;9;22)(q11;q34;q11) (87%). Hyperdiploidy was present in two cells. In this study, both conventional cytogenetic and FISH diagnosis proved to be significant to identify the variant nature of the Philadelphia chromosome and hyperdiploid condition for introduction of a suitable treatment regimen and estimation of life expectancy of the young girl.


Assuntos
Cromossomos Humanos Par 7/genética , Proteínas de Fusão bcr-abl/genética , Hibridização in Situ Fluorescente , Leucemia Mielogênica Crônica BCR-ABL Positiva/diagnóstico , Translocação Genética , Medula Óssea/ultraestrutura , Criança , Diploide , Feminino , Humanos , Cariotipagem , Cromossomo Filadélfia
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