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1.
Am J Hum Biol ; : e24087, 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38682460

RESUMO

OBJECTIVES: To evaluate the reliability of data from the assay of bio-archived specimens, a 50-freeze-thaw-cycle (FTC) degradation study of fresh sera was conducted to test the stability of 16 immunoregulators. METHODS: Twenty de-identified serum specimens were obtained from volunteers at United Health Services-Wilson Memorial Hospital. Specimens were stored at -20°C and underwent daily 1 h thawing and subsequent freezing for each FTC over 50 consecutive days. Immunoregulator concentrations were assessed via enzyme-linked immunosorbent assay (ELISA) in participant samples at 2 FTC (baseline), 25 FTC, and 50 FTC. Specific immunoregulators observed in the study were C-reactive protein (CRP), interleukin (IL)-1α, 4, 6, 8, 10, monocyte chemoattractant protein-1 (MCP-1, CCL2), monocyte chemoattractant protein-2 (MCP-2, CCL8), eotaxin-1, thymus-and-activation-regulated chemokine (TARC, CCL17), regulated on activation normal T-cell expressed and secreted (RANTES, CCL5), growth-regulated oncogene-alpha (GRO-α, CXCL1), small inducible cytokine A1 (I-309, CCL1), interferon-gamma (IFN-γ), interferon-gamma inducible protein-10 (IP-10, CXCL10), and tumor necrosis factor-alpha (TNF-α). RESULTS: Quantitative stability of serum immunoregulators: Serum CRP, IL-8, IL-10, IFN-γ, IP-10, and eotaxin-1 levels appear to be statistically equivalent from baseline to 50 FTC (p ≤ .05). Retention of patterns in serum immunoregulators: patterns across FTC were retained for TARC (age) and CRP, IFN-γ, and MCP-2 (sex). CONCLUSIONS: While the effect of multiple FTC on serum immunoregulator levels may not replicate prolonged freezer storage, the results of this study provide valuable information on the robustness of immunoregulators for research using bio-archived sera.

2.
Med Vet Entomol ; 31(1): 1-5, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27699814

RESUMO

There is a public perception that the white-tailed deer Odocoileus virginianus (Artiodactyla: Cervidae) is the main reservoir supporting the maintenance and spread of the causative agent of Lyme disease, Borrelia burgdorferi. This study examines the pathogen prevalence rate of Borrelia in adult Ixodes scapularis (Ixodida: Ixodidae), the black-legged tick, collected from white-tailed deer and compares it with pathogen prevalence rates in adult ticks gathered by dragging vegetation in two contiguous counties west of the Hudson Valley in upstate New York. In both Broome and Chenango Counties, attached and unattached ticks harvested from white-tailed deer had significantly lower prevalences of B. burgdorferi than those collected from vegetation. No attached ticks on deer (n = 148) in either county, and only 2.4 and 7.3% of unattached ticks (n = 389) in Broome and Chenango Counties, respectively, were harbouring the pathogen. This contrasts with the finding that 40.8% of ticks in Broome County and 46.8% of ticks in Chenango County collected from vegetation harboured the pathogen. These data suggest that a mechanism in white-tailed deer may aid in clearing the pathogen from attached deer ticks, although white-tailed deer do contribute to the spatial distribution of deer tick populations and also serve as deadend host breeding sites for ticks.


Assuntos
Borrelia burgdorferi/fisiologia , Cervos , Reservatórios de Doenças/veterinária , Ixodes/microbiologia , Doença de Lyme/epidemiologia , Infestações por Carrapato/veterinária , Animais , Reservatórios de Doenças/microbiologia , Ixodes/fisiologia , Doença de Lyme/microbiologia , Doença de Lyme/transmissão , New York/epidemiologia , Infestações por Carrapato/epidemiologia , Infestações por Carrapato/parasitologia
3.
Public Health ; 128(9): 860-8, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25225155

RESUMO

OBJECTIVES: It is currently unknown whether chronic wasting disease (CWD), a transmissible spongiform encephalopathy of cervids, is transmissible to humans. Reported on here are the behavioural risk factors and health conditions associated with a six-year follow-up of a known point-source exposure to a CWD infected deer in an Upstate New York community. STUDY DESIGN: Longitudinal. METHODS: The Oneida County Chronic Wasting Disease Surveillance Project was launched in 2005 in response to a point-source exposure to a CWD infected deer at a March 2005 Sportsmen's feast in Upstate New York. Eighty-one exposed individuals participated in the 2005 baseline data collection, and were sent follow-up questionnaires following each deer hunting season between 2005 and 2011. RESULTS: Over a six year period, participants reported a reduction in overall venison consumption. Participants reported no significant changes in health conditions, although several conditions (vision loss, heart disease, type 2 diabetes, weight changes, hypertension, and arthritis), were significantly associated with age. CONCLUSIONS: To this day, this incident remains the only known large-scale point-source exposure to a CWD infected deer. Prion diseases can incubate for multiple decades before the manifestation of clinical symptoms; thus, continued surveillance of this exposed study population represents a unique opportunity to assess the risk of CWD transmission to humans. This project is uniquely situated to provide the first epidemiological evidence of CWD transmission to humans, should it occur.


Assuntos
Cervos , Exposição Ambiental , Contaminação de Alimentos , Vigilância da População , Doença de Emaciação Crônica/transmissão , Adulto , Idoso , Animais , Seguimentos , Humanos , Pessoa de Meia-Idade , New York/epidemiologia , Assunção de Riscos , Inquéritos e Questionários , Doença de Emaciação Crônica/epidemiologia , Zoonoses
4.
Brain Res Rev ; 58(1): 136-48, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18342372

RESUMO

DNA is a dynamic molecule, the conformation of which plays a major role in biological function. The non-B-form of DNA conformations are reported in the patho-physiology of diseases like Fragile X-syndrome, Huntington's chorea, Alzheimer's and others. Recently, our laboratory discovered the presence of Z-DNA in the hippocampal region of severely affected Alzheimer's disease (AD) brain samples. Alternate purine-pyrimidine bases, potential sequences adopting Z-DNA, are present in the promoter regions of AD specific genes like amyloid precursor protein (APP), Presenilin and ApoE. Thus, Z-DNA might be involved in the expression of these pathologically important genes. In the present review, we have focused on the possible mechanisms/hypothetical models of Z-DNA transition and its implications in AD. We propose that Z-DNA is formed in the promoter region of the APP, and Presenilin genes and Z-DNA may absorb the negative supercoils at that region. This decreases the supercoil density, altering the domain's native supercoiling state and facilitates the binding of effectors, which positively regulate gene expression of AD-related genes like APP and Presenilin. Further, it is presumed that Z-DNA may be involved in the down regulation of genes involved in Abeta clearance, anti-oxidant and defense mechanisms in AD. The proposed working model is novel and reveals possible triggering factors or precursors, which regulate the modulation of the supercoiling level of DNA involving putative Z-DNA forming sequences and regulatory proteins binding to DNA in AD.


Assuntos
Doença de Alzheimer/genética , Peptídeos beta-Amiloides/genética , Precursor de Proteína beta-Amiloide/genética , DNA Forma Z/genética , Doença de Alzheimer/metabolismo , Doença de Alzheimer/fisiopatologia , Peptídeos beta-Amiloides/metabolismo , Peptídeos beta-Amiloides/fisiologia , Precursor de Proteína beta-Amiloide/metabolismo , Precursor de Proteína beta-Amiloide/fisiologia , Animais , Regulação da Expressão Gênica , Humanos , Modelos Biológicos , Regiões Promotoras Genéticas/genética , Transcrição Gênica
5.
Cell Mol Life Sci ; 62(2): 143-58, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15666086

RESUMO

Aluminium, an environmentally abundant non-redox trivalent cation has long been implicated in the pathogenesis of Alzheimer's disease (AD). However, the definite mechanism of aluminium toxicity in AD is not known. Evidence suggests that trace metal homeostasis plays a crucial role in the normal functioning of the brain, and any disturbance in it can exacerbate events associated with AD. The present paper reviews the scientific literature linking aluminium with AD. The focus is on aluminium levels in brain, region-specific and subcellular distribution, its relation to neurofibrillary tangles, amyloid beta, and other metals. A detailed mechanism of the role of aluminium in oxidative stress and cell death is highlighted. The importance of complex speciation chemistry of aluminium in relation to biology has been emphasized. The debatable role of aluminium in AD and the cross-talk between aluminium and genetic susceptibility are also discussed. Finally, it is concluded based on extensive literature that the neurotoxic effects of aluminium are beyond any doubt, and aluminium as a factor in AD cannot be discarded. However, whether aluminium is a sole factor in AD and whether it is a factor in all AD cases still needs to be understood.


Assuntos
Alumínio/toxicidade , Doença de Alzheimer/etiologia , Encéfalo/efeitos dos fármacos , Alumínio/sangue , Doença de Alzheimer/induzido quimicamente , Animais , Encéfalo/fisiopatologia , Morte Celular , Predisposição Genética para Doença , Humanos , Metais/toxicidade , Emaranhados Neurofibrilares/metabolismo , Estresse Oxidativo , Ratos
6.
Ann Hum Biol ; 31(3): 292-310, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15204346

RESUMO

BACKGROUND: Studies comparing the growth of indigenous high-altitude Aymara children and children of low-altitude European descent who have been born and raised at high altitude in the Andes have provided evidence for genetically-determined differences in thorax growth, as well as for population differences in height, weight and other measures of overall size. Comparable studies now can be undertaken in Asia because of the growing number of Han Chinese who have been born and raised at high altitude on the Qinghai-Tibetan Plateau. AIM: The study compares the growth of indigenous Tibetan children and children of Han descent who have been born and raised at the same high altitudes, and under similar socio-economic conditions. SUBJECTS AND METHODS: Measurements of stature, sitting height, weight, triceps and subscapular skinfolds, upper arm muscle area, transverse chest diameter, anterio-posterior chest diameter, and chest circumference were taken on 1439 Tibetan and Han males and females between the ages of 6 and 29 years who were born and raised 3200 m, 3800 m or at 4300 m in the high altitude province of Qinghai in western China. RESULTS: Han-Tibetan differences in body size do not occur systematically for any measurement, for any age group, or for either gender; nor is there a systematic pattern of body size differences between 3200 m and 4300 m. This indicates that there are no differences in general growth between the two groups at high altitude in Qinghai, although both groups grow more slowly than urban children at low altitude in China. On the other hand, Tibetan males possess significantly deeper chests than Han males, and Tibetan females possess significantly wider chests than Han females. Tibetans of both sexes possess significantly larger chest circumferences than Han males and females. CONCLUSIONS: Although genetic similarities cannot be ruled out, comparable dietary stress is a likely explanation for the similar and slow morphological growth of Han and Tibetans at high altitude. However, Han-Tibetan differences in thorax dimensions are likely a consequence of population (genetic) differences in the response to hypoxia during growth.


Assuntos
Altitude , Estatura , Peso Corporal , Dobras Cutâneas , Tórax/crescimento & desenvolvimento , Adolescente , Adulto , Criança , China , Feminino , Humanos , Masculino , Vigilância da População , Tibet
7.
Neurology ; 58(5): 765-73, 2002 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-11889241

RESUMO

BACKGROUND: It was noticed in the mid-1950s that the incidence of ALS and parkinsonism--dementia complex (PDC) were much higher on Guam than anywhere else in the world. In 1958, a registry of patients and controls was established to ascertain the familial and genetic aspects of these diseases. Patients and individually matched controls and their relatives were registered from 1958 to 1963. The registry was updated and analyzed in 1998 through 1999. OBJECTIVE: To ascertain whether first-degree relatives of patients had a higher risk for developing ALS or PDC than relatives of controls. METHODS: During the period of 1958 to 1963, 126 new patients and 126 individually matched controls and their respective first-degree relatives and spouses were evaluated neurologically and registered. Forty years later, the number of new cases among the patient and control relatives were compared to an expected number of new cases based on the age- and sex-specific incidence of ALS and PDC in the population at large. RESULTS: From 1958 to 1999, there were 102 new ALS or PDC cases among relatives of patients and 33 among relatives of controls. These values were compared with the derived expected values. There were more observed than expected new cases among patients' relatives, and less observed cases than expected among the controls' relatives. CONCLUSIONS: Relatives of patients with ALS or PDC have significantly higher risks for developing the disease than the Guamanian population, whereas relatives of controls have significantly lower risks.


Assuntos
Esclerose Lateral Amiotrófica/epidemiologia , Doença de Parkinson/epidemiologia , Sistema de Registros , Idoso , Esclerose Lateral Amiotrófica/etiologia , Esclerose Lateral Amiotrófica/genética , Saúde da Família , Feminino , Predisposição Genética para Doença , Guam/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Núcleo Familiar , Doença de Parkinson/etiologia , Doença de Parkinson/genética , Fatores de Risco
8.
Arch Neurol ; 58(11): 1871-8, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11708997

RESUMO

BACKGROUND: A Guam variant of amyotrophic lateral sclerosis (ALS-G) and parkinsonism dementia complex (PDC-G) are found in the Chamorro people of Guam. Both disorders have overlapping neuropathologic findings, with neurofibrillary tangles in spinal cord and brain. The cause of ALS-G-PDC-G is unknown, although inheritance and environment appear important. Because neurofibrillary tangles containing tau protein are present in ALS-G-PDC-G, and because mutations in the tau gene (TAU) cause autosomal dominant frontotemporal dementia, TAU was examined as a candidate gene for ALS-G-PDC-G. METHODS: TAU was evaluated by DNA sequence analysis in subjects with ALS-G-PDC-G, by linkage analysis of TAU polymorphisms in an extended pedigree from the village of Umatac, and by evaluation of linkage disequilibrium with polymorphic markers flanking and within TAU. RESULTS: Linkage disequilibrium between ALS-G-PDC-G and the TAU polymorphism CA3662 was observed. For this 2-allele system, PDC and ALS cases were significantly less likely than Guamanian controls to have the 1 allele (4.9% and 2% vs 11.5%, respectively; Fisher exact P =.007). DNA sequence analysis of TAU coding regions did not demonstrate a mutation responsible for ALS-G-PDC-G. Analysis of TAU genotypes in an extended pedigree of subjects from Umatac showed obligate recombinants between TAU and ALS-G-PDC-G. Linkage analysis of the Umatac pedigree indicates that TAU is not the major gene for ALS-G-PDC-G. CONCLUSIONS: The genetic association between ALS-G-PDC-G implicates TAU in the genetic susceptibility to ALS-G-PDC-G. TAU may be a modifying gene increasing risk for ALS-G-PDC-G in the presence of another, as yet, unidentified gene.


Assuntos
Esclerose Lateral Amiotrófica/genética , Demência/genética , Predisposição Genética para Doença , Transtornos Parkinsonianos/genética , Proteínas tau/genética , Adulto , Idoso , Esclerose Lateral Amiotrófica/diagnóstico , Esclerose Lateral Amiotrófica/fisiopatologia , Demência/diagnóstico , Demência/fisiopatologia , Feminino , Frequência do Gene , Guam , Humanos , Desequilíbrio de Ligação/genética , Masculino , Pessoa de Meia-Idade , Transtornos Parkinsonianos/diagnóstico , Transtornos Parkinsonianos/fisiopatologia , Linhagem , Polimorfismo Genético , Análise de Sequência de DNA
9.
J Infect Dis ; 183(2): 192-196, 2001 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-11120925

RESUMO

Kuru reached epidemic proportions by the mid-twentieth century among the Fore people of New Guinea and disappeared after the abolition of cannibalistic rituals. To determine susceptibility to kuru and its role in the spread and elimination of the epidemic, we analyzed the PRNP gene coding sequences in 5 kuru patients; no germline mutations were found. Analysis of the PRNP 129 methionine (M)/valine (V) polymorphism in 80 patients and 95 unaffected controls demonstrated that the kuru epidemic preferentially affected individuals with the M/M genotype. A higher representation of M/M carriers was observed among the affected young Fore males entering the age of risk, whereas a lower frequency of M/M homozygotes was found among the survivors. M/V and V/V genotypes predisposed to a lower risk of disease development and longer incubation times. These findings are relevant to the current outbreak of variant Creutzfeldt-Jakob disease (vCJD) in the United Kingdom, because all vCJD patients tested thus far have been M/M carriers.


Assuntos
Amiloide/genética , Surtos de Doenças , Predisposição Genética para Doença , Kuru/genética , Metionina/genética , Precursores de Proteínas/genética , Criança , Pré-Escolar , Códon , Feminino , Genótipo , Humanos , Lactente , Kuru/epidemiologia , Masculino , Mutação , Nova Guiné/epidemiologia , Polimorfismo Genético , Proteínas Priônicas , Príons , Análise de Sequência de DNA
10.
Hum Biol ; 72(1): 179-99, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10721617

RESUMO

Human adaptability, as a field of inquiry within human biology, became defined during the research activities of the International Biological Program (IBP) (1964-1974). During this period, research was focused on ecological, physiological, and genetic studies of human populations within the theoretical frameworks of adaptation and evolution. Other defining characteristics of the IBP human adaptability research were standardization of methods, multidisciplinary projects, international cooperation, and a concern with human health issues. Some observers suggest that this research contributed to the ongoing transformation of physical anthropology and related fields from a largely descriptive to an analytical science. During the 25 years between the end of the IBP and the present, a number of research trends have continued: Several new multidisciplinary projects were initiated and completed; a subfield of demography within human biology has matured; nutrition, infant and child growth, and health studies have proliferated; and molecular genetics and DNA analysis have superseded the earlier population genetics. International programs today are geared toward more practical and applied studies with less emphasis on basic science. Continuation of human adaptability research into the 21st century is likely to make contributions in 3 broad areas: population, environment, and health. Productive research is likely to contribute to these 3 areas in the following categories: reproduction, psychosocial stress, life span approaches to health, effects of losses in biodiversity on health, a human biology of poverty, emerging infectious diseases, epidemiology of modernization, evolutionary medicine, and aging. The success of much of this research in its contribution to knowledge will come from the integrated perspectives of a biobehavioral framework of inquiry.


Assuntos
Adaptação Fisiológica/genética , Adaptação Psicológica , Evolução Biológica , Genética Populacional , Pesquisa/história , Ecossistema , Meio Ambiente , Previsões , Saúde Global , História do Século XX , Humanos , Longevidade/genética , Modelos Genéticos , Avaliação das Necessidades , Reprodução/genética , Estresse Psicológico/genética , Estresse Psicológico/psicologia
11.
Am J Phys Anthropol ; 111(1): 69-88, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10618589

RESUMO

This study compares the stature, weight, skinfolds, upper arm muscle area, and chest dimensions of Tibetan children, adolescents, and young adults who were born and raised, or who had lived from infancy, at 3,200 m, 3,800 m, and 4,300 m in Qinghai Province, People's Republic of China. While the individuals measured in Qinghai are among the tallest and heaviest Tibetans reported in the literature, they are nevertheless smaller and lighter than well-off children living at low altitude. The pattern of size variation among Tibetan males and females measured at the three high altitudes, along with evidence of a secular trend at 4,300 m, suggests that nutrition may significantly effect growth at high altitude. Only minor differences in thorax dimensions exist between Tibetan males and females measured at 3,200 m and 3,800 m. However, Tibetan males at 4,300 m possess slightly narrower and deeper chests (during and after adolescence) than males at 3,200 m and 3,800 m. Since individuals from 3,800 m and 4,300 m belong to the same local populations, this characteristic is unlikely to be genetically determined. However, it may be related to differences in the degree of hypoxia or to the influences of other environmental conditions.


Assuntos
Altitude , Estatura , Crescimento , Adolescente , Adulto , Criança , Feminino , Genética Populacional , Humanos , Hipóxia , Masculino , Estado Nutricional , Fatores Sexuais , Tibet
12.
Proc Natl Acad Sci U S A ; 96(18): 10536-43, 1999 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-10468644

RESUMO

During the past four decades, biomedical scientists have slowly begun to recognize the unique opportunities for studying biomedical processes, disease etiology, and mechanisms of pathogenesis in populations with unusual genetic structures, physiological characteristics, focal endemic disease, or special circumstances. Such populations greatly extend our research capabilities and provide a natural laboratory for studying relationships among biobehavioral, genetic, and ecological processes that are involved in the development of disease. The models presented illustrate three different types of natural experiments: those occurring in traditionally living, modernizing, and modern populations. The examples are drawn from current research that involves population mechanisms of adaptation among East African Turkana pastoralists; a search for etiology and mechanisms of pathogenesis of an emerging disease among the Yakut people of Siberia; and psychosocial stress, hypertension, and cardiovascular disease in women working outside the home in New York City and among subpopulations in Hawaii. The models in general, and the examples in specific, represent natural laboratories in which relatively small intrapopulation differences and large interpopulation differences can be used to evaluate health and disease outcomes.


Assuntos
Antropologia Cultural , Modelos Biológicos , África Oriental , Comportamento , Doenças Cardiovasculares/epidemiologia , Países Desenvolvidos , Países em Desenvolvimento , Ecossistema , Epidemiologia , Feminino , Humanos , Hipertensão/epidemiologia , Relações Interpessoais , Cidade de Nova Iorque/epidemiologia , Sibéria , Estresse Psicológico/epidemiologia , Mulheres Trabalhadoras
13.
Ann Neurol ; 43(6): 815-25, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9629852

RESUMO

Frontotemporal dementia with parkinsonism, chromosome 17 type (FTDP-17), a recently defined disease entity, is clinically characterized by personality changes sometimes associated with psychosis, hyperorality, and diminished speech output, disturbed executive function and nonfluent aphasia, bradykinesia, and rigidity. Neuropathological changes include frontotemporal atrophy often associated with atrophy of the basal ganglia, substantia nigra, and amygdala. Neurofibrillary tangles (NFTs) are seen in some but not all families. Inheritance is autosomal dominant and the gene has been regionally localized to 17q21-22 in a 2- to 4-centimorgan (cM) region flanked by markers D17S800 and D17S791. The gene for tau, the primary component of NFTs, is located in the same region of chromosome 17. Tau was evaluated as a candidate gene. Physical mapping studies place tau within 2 megabases or less of D17S791, but it is probably outside the D17S800-D17S791 FTDP-17 interval. DNA sequence analysis of tau coding regions in affected subjects from two FTDP-17 families revealed nine DNA sequence variants, eight of which were also identified in controls and are thus polymorphisms. A ninth variant (Val279Met) was found in one FTDP-17 family but not in the second FTDP-17 family. Three lines of evidence indicate that the Val279Met change is an FTDP-17 causative mutation. First, the mutation site is highly conserved, and a normal valine is found at this position in all three tau interrepeat sequences and in other microtubule associated protein tau homologues. Second, the mutation co-segregates with the disease in family A. Third, the mutation is not found in normal controls.


Assuntos
Cromossomos Humanos Par 17 , Demência/genética , Lobo Frontal/fisiopatologia , Lobo Temporal/fisiopatologia , Proteínas tau/genética , Mapeamento Cromossômico , Primers do DNA , Saúde da Família , Feminino , Ligação Genética , Humanos , Masculino , Dados de Sequência Molecular , Linhagem , Polimorfismo Genético , Homologia de Sequência de Aminoácidos
15.
Brain Res ; 748(1-2): 237-40, 1997 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-9067468

RESUMO

We determined the influence of aluminum on dendritic transport, using an in vitro system of dissociated mouse hippocampal neurons. Newly synthesized RNA from dissociated mouse hippocampal neurons was more slowly transported into dendrites in the presence of aluminum chloride when compared to those without the addition of aluminum chloride to the culture medium. Suppression of dendritic transport of newly synthesized RNA may be responsible for the dendritic degeneration observed in aluminum neurotoxicity, eventually leading to neuronal degeneration.


Assuntos
Alumínio/farmacologia , Dendritos/metabolismo , Hipocampo/metabolismo , Neurônios/metabolismo , Animais , Transporte Biológico/efeitos dos fármacos , Hipocampo/citologia , Camundongos , RNA/metabolismo
16.
Acta Neuropathol ; 92(6): 545-54, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8960311

RESUMO

Amyotrophic lateral sclerosis (ALS) is characterized neuropathologically by chromatolysis, Bunina bodies, hyaline inclusions, skein-like inclusions and axonal spheroids. Aluminum, a known neurotoxin, is the cause of dialysis encephalopathy and is considered to be a causative agent in high incidence foci of ALS in the western Pacific. We have developed an experimental model of motor neuron degeneration in New Zealand white rabbits using chronic low-dose intracisternal administration of aluminum and compared the clinical and neuropathological changes to those of human ALS. Aluminum-inoculated rabbits developed progressive hyperreflexia, hypertonia, limb splaying, gait impairment, muscle wasting, hindlimb paralysis and impaired tonic immobility responses without overt encephalopathic features over a 14-month period. Examination of spinal cords from these animals demonstrated the frequent occurrence and progressive development of anterior horn cell lesions that included small, round, argentophilic perikaryal inclusions similar to hyaline inclusions seen in human ALS. Other inclusions were more condensed and eosinophilic, while still others had neurofibrillary tangle-like morphologies. Axonal spheroids and neuritic thickenings were also prominent and were identical to those seen in human ALS. We believe that the similar and progressive development of neuropathological changes observed in the chronic aluminum-intoxication model, compared to human ALS, warrants further study to aid in understanding the cellular and molecular mechanisms of human motor neuron disease.


Assuntos
Alumínio/intoxicação , Esclerose Lateral Amiotrófica/patologia , Tronco Encefálico/efeitos dos fármacos , Tronco Encefálico/patologia , Corpos de Inclusão/ultraestrutura , Medula Espinal/efeitos dos fármacos , Medula Espinal/patologia , Esclerose Lateral Amiotrófica/metabolismo , Animais , Tronco Encefálico/metabolismo , Humanos , Imuno-Histoquímica , Microscopia Eletrônica , Coelhos , Medula Espinal/metabolismo , Fatores de Tempo
17.
Neurodegeneration ; 5(4): 325-9, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9117544

RESUMO

Maltol (3-hydroxy-2-methyl-4-pyrone), a product of carbohydrate degradation, is known to enhance aluminium-induced neurofibrillary degeneration in neuronal systems, but few toxicological studies have been conducted. We report maltol toxicity in neuroblastoma cell lines of mouse (Neuro 2a) and human (IMR 32) origin, and in primary murine fetal hippocampal neuronal cultures. As determined by MTS [3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2 -(4-sulfophenyl)-2H-tetrazolium, inner salt] conversion, maltol exhibited a dose-dependent toxicity on the viability of both neuroblastoma cell lines, but the toxicity was more pronounced in Neuro 2a cells. Maltol was also toxic in a dose-dependent manner in primary murine fetal hippocampal neurons at micromolar concentrations. Electrophoresis of DNA extracted from maltol-intoxicated cells showed a laddering pattern, suggestive of apoptotic cell death. In the maltol-exposed hippocampal neuronal cultures, fragmented DNA ends were visualized in situ in morphologically condensed nuclei by terminal deoxynucleotidyl transferase with digoxigenin-labelled UTP and subsequent immunohistochemistry. Collectively, our findings suggest that the toxic effect of maltol is mediated through apoptosis. Further toxicological investigations are warranted, since maltol is found in the daily diet of humans.


Assuntos
Hipocampo/citologia , Neuroblastoma/patologia , Neurônios/efeitos dos fármacos , Pironas/intoxicação , Animais , Apoptose , Sobrevivência Celular , Células Cultivadas , Fragmentação do DNA , Hipocampo/embriologia , Humanos , Camundongos/embriologia , Neurônios/ultraestrutura , Concentração Osmolar , Células Tumorais Cultivadas/efeitos dos fármacos
18.
J Toxicol Environ Health ; 48(6): 599-613, 1996 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-8772801

RESUMO

Regardless of the host, the route of administration, or the speciation, aluminum is a potent neurotoxicant. In the young adult or developmentally mature host, the neuronal response to Al exposure can be dichotomized on morphological grounds. In one, intraneuronal neurofilamentous aggregates are formed, whereas in the other, significant neurochemical and neurophysiological perturbations are induced without neurofilamentous aggregate formation. Evidence is presented that the induction of neurofilamentous aggregates is a consequence of alterations in the posttranslational processing of neurofilament (NF), particularly with regard to phosphorylation state. Although Al has been reported to impact on gene expression, this does not appear to be critical to the induction of cytoskeletal pathology. In hosts responding to Al exposure without the induction of cytoskeletal pathology, impairments in glucose utilization, agonist-stimulated inositol phosphate accumulation, free radical-mediated cytotoxicity, lipid peroxidation, reduced cholinergic function, and altered protein phosphorylation have been described. The extent to which these neurochemical modifications correlate with the induction of a characteristic neurobehavioral state is unknown. In addition to these paradigms, Al is toxic in the immediate postnatal interval. Whether unique mechanisms of toxicity are involved during development remains to be determined. In this article, the mechanisms of Al neurotoxicity are reviewed and recommendations are put forth with regard to future research. Primary among these is the determination of the molecular site of Al toxicity, and whether this is based on Al substitution for divalent metals in a number of biological processes. Encompassed within this is the need to further understand the genesis of host- and developmental-specific responses.


Assuntos
Alumínio/efeitos adversos , Sistema Nervoso Central/efeitos dos fármacos , Prenhez/efeitos dos fármacos , Adulto , Alumínio/farmacocinética , Animais , Sistema Nervoso Central/fisiopatologia , Citoesqueleto/efeitos dos fármacos , Citoesqueleto/patologia , Desenvolvimento Embrionário e Fetal/efeitos dos fármacos , Feminino , Expressão Gênica , Humanos , Metabolismo/efeitos dos fármacos , Neuroquímica/métodos , Neurofisiologia/métodos , Gravidez , Projetos de Pesquisa
19.
Neurotoxicology ; 16(3): 511-7, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-8584282

RESUMO

The presence of both aluminum (Al) and manganese (Mn) in central nervous system tissues (CNS) has been reported in Parkinson's disease and in parkinsonism-dementia (PD) on Guam. Epidemiological surveys on Guam have suggested that low calcium (Ca), magnesium (Mg) and high Al and Mn in river, soil and drinking water may be implicated in the pathogenesis of PD. Experimentally, low Ca-Mg diets with or without added Al have been found to accelerate Al deposition in the CNS of rats and monkeys. Although excessive deposition of Mn produces similar neurotoxic action to Al in CNS tissues, the mechanism of Mn deposition coupled with Al loading in the presence of low Ca-Mg intake is not yet known. In this study, the deposition and mental-metal interaction of both Al and Mn in the CNS, visceral organs and bones of rats fed unbalanced mineral diets were analyzed. Male Wistar rats, weighing 200 g, were maintained for 90 days on the following diets: (A) standard diet, (B) low Ca diet, (C) low Ca-Mg diet, (D) low Ca-Mg diet with high Al. Al and Mn content were determined in the frontal cortex, spinal cord, kidney, muscle, abdominal aorta, femur and lumbar spine using neutron activation analysis (NAA). Our results demonstrate that serum Ca levels were decreased in the following dietary order: C

Assuntos
Osso e Ossos/metabolismo , Cálcio da Dieta/farmacologia , Sistema Nervoso Central/metabolismo , Dieta , Manganês/metabolismo , Alumínio/metabolismo , Animais , Osso e Ossos/efeitos dos fármacos , Sistema Nervoso Central/efeitos dos fármacos , Masculino , Ratos , Ratos Wistar , Distribuição Tecidual
20.
J Anal Toxicol ; 18(7): 361-8, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-7861748

RESUMO

The plasticizer, n-butylbenzenesulfonamide (NBBS), is reported to be neurotoxic when inoculated intracisternally or intraperitoneally into rabbits. Because NBBS is commonly used in the production of polyamide (nylon) plastics and is soluble in water, the disposal of NBBS-containing plastics in landfill sites could result in NBBS appearing in the leachate. Further, NBBS could also be leached from packaging into their contents. To allow us to examine the risks posed by NBBS in the environment, we have developed a quantitative assay for this compound. The assay employs a one-step extraction into dichloromethane followed by gas chromatography with accurate mass selected ion recording. The assay incorporates [13C6]NBBS as an internal standard to allow precise quantitation, and four separate ion chromatograms are recorded. NBBS was found in some Australian domestic solidwaste landfill leachate (from less than 0.3 to 94.6 ng/mL), but ground water in the vicinity of a landfill had only trace quantities of NBBS. NBBS was also quantitated in some bottled and cask wines, and levels varied from not detected to 2.17 ng/mL (n = 14). Additional studies are required to assess the public health risks associated with the use of NBBS as a plasticizer.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Plastificantes/análise , Sulfonamidas/análise , Cromatografia Gasosa-Espectrometria de Massas/instrumentação , Solventes/química , Sulfonamidas/síntese química , Água/química , Vinho
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