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1.
J Nutr Health Aging ; 26(7): 681-687, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35842758

RESUMO

OBJECTIVES: We aimed to examine the association of muscle evaluation, including muscle ultrasound, with hospital-associated disability (HAD), focusing on ADL categories. DESIGN: A prospective observational cohort study. SETTING AND PARTICIPANTS: We recruited patients aged 65 years or older who were admitted to the geriatric ward of an acute hospital between October 2019 and September 2021. MEASUREMENTS: Handgrip strength, bioimpedance analyzer-determined skeletal muscle mass, bilateral thigh muscle thickness (BATT), and the echo intensity of the rectus femoris on muscle ultrasound were performed as muscle assessments. HAD was evaluated separately for mobility impairments and self-care impairments. RESULTS: In total, 256 individuals (mean age, 85.2 years; male sex, 41.8%) were analyzed. HAD in mobility was more common than HAD in self-care (37.5% vs. 30.0%). Only BATT was independently associated with HAD in mobility in multiple logistic regression analysis. There was no significant association between muscle indicators and HAD in self-care. CONCLUSION: A lower BATT was associated with a higher prevalence of HAD in mobility, suggesting the need to reconsider muscle assessment methods in hospitalized older adults. In addition, approaches other than physical may be required, such as psychosocial and environmental interventions to improve HAD in self-care.


Assuntos
Sarcopenia , Idoso , Idoso de 80 Anos ou mais , Avaliação da Deficiência , Força da Mão , Hospitais , Humanos , Masculino , Força Muscular/fisiologia , Músculo Esquelético/diagnóstico por imagem , Estudos Prospectivos , Sarcopenia/epidemiologia
2.
RSC Adv ; 10(20): 11755-11765, 2020 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-35496632

RESUMO

The macrocyclic ligand calix[4]arene (L1) and its sulphur-containing analogue thia[4]calixarene (L2) are promising precursors for functional molecular materials as they offer rational functionalization with various organic groups. Here, we present the first example of lanthanide-based coordination polymers built from the macrocyclic thiacalix[4]arene backbone bearing four carboxylic moieties, namely, ligand H4L3. The combination of H4L3 with the Tb3+ and Dy3+ cations led to the formation of 1D ladder-type coordination polymers with the formula [LnIIIHL3DMF3]·(DMF) (where DMF = dimethylformamide and Ln = Tb or Dy, denoted as HL3-Tb and HL3-Dy), which resulted from the coordination of the lanthanide cations with the partially deprotonated ligand HL33- that behaved as a T-shape connector. The coordination sphere around the metal was completed by the coordinated DMF solvent molecules. By combining both Tb3+ and Dy3+ cations, isostructural heterobimetallic solid solutions HL3-Tb1- x Dy x were also prepared. HL3-Tb and HL3-Dy showed visible light photoluminescence originating from the f-f electronic transitions of pale green emissive Tb3+ and pale yellow emissive Dy3+ with efficient sensitization by the functionalized thia[4]calixarene ligand HL3. In the HL3-Tb1- x Dy x solid solutions, the Tb/Dy ratio governed both the emission colour as well as the emission quantum yield, which reached even 28% at room temperature for HL3-Tb. Moreover, HL3-Dy exhibited a slow magnetic relaxation effect related to the magnetic anisotropy of the dodecahedral Dy3+ complexes, which were well isolated in the crystal lattice by expanded organic spacers.

3.
Science ; 251(4989): 90-3, 1991 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-1702556

RESUMO

Members of the fibroblast growth factor (FGF) family of proteins stimulate the proliferation and differentiation of a variety of cell types through receptor-mediated pathways. The three-dimensional structures of two members of this family, bovine acidic FGF and human basic FGF, have been crystallographically determined. These structures contain 12 antiparallel beta strands organized into a folding pattern with approximate threefold internal symmetry. Topologically equivalent folds have been previously observed for soybean trypsin inhibitor and interleukins-1 beta and -1 alpha. The locations of sequences implicated in receptor and heparin binding by FGF are presented. These sites include beta-sheet strand 10, which is adjacent to the site of an extended sequence insertion in several oncogene proteins of the FGF family, and which shows sequence conservation among the FGF family and interleukin-1 beta.


Assuntos
Fator 1 de Crescimento de Fibroblastos/química , Fator 2 de Crescimento de Fibroblastos/química , Sequência de Aminoácidos , Animais , Bovinos , Fenômenos Químicos , Físico-Química , Cristalização , Fator 1 de Crescimento de Fibroblastos/metabolismo , Fator 2 de Crescimento de Fibroblastos/metabolismo , Heparina/metabolismo , Humanos , Interleucina-1/química , Dados de Sequência Molecular , Estrutura Molecular , Conformação Proteica , Proteínas Recombinantes/química , Homologia de Sequência do Ácido Nucleico , Difração de Raios X
4.
Science ; 257(5077): 1653-9, 1992 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-1529353

RESUMO

The nitrogenase enzyme system catalyzes the ATP (adenosine triphosphate)-dependent reduction of dinitrogen to ammonia during the process of nitrogen fixation. Nitrogenase consists of two proteins: the iron (Fe)-protein, which couples hydrolysis of ATP to electron transfer, and the molybdenum-iron (MoFe)-protein, which contains the dinitrogen binding site. In order to address the role of ATP in nitrogen fixation, the crystal structure of the nitrogenase Fe-protein from Azotobacter vinelandii has been determined at 2.9 angstrom (A) resolution. Fe-protein is a dimer of two identical subunits that coordinate a single 4Fe:4S cluster. Each subunit folds as a single alpha/beta type domain, which together symmetrically ligate the surface exposed 4Fe:4S cluster through two cysteines from each subunit. A single bound ADP (adenosine diphosphate) molecule is located in the interface region between the two subunits. Because the phosphate groups of this nucleotide are approximately 20 A from the 4Fe:4S cluster, it is unlikely that ATP hydrolysis and electron transfer are directly coupled. Instead, it appears that interactions between the nucleotide and cluster sites must be indirectly coupled by allosteric changes occurring at the subunit interface. The coupling between protein conformation and nucleotide hydrolysis in Fe-protein exhibits general similarities to the H-Ras p21 and recA proteins that have been recently characterized structurally. The Fe-protein structure may be relevant to the functioning of other biochemical energy-transducing systems containing two nucleotide-binding sites, including membrane transport proteins.


Assuntos
Azotobacter vinelandii/enzimologia , Proteínas Ferro-Enxofre/química , Nitrogenase/química , Difosfato de Adenosina/metabolismo , Trifosfato de Adenosina/metabolismo , Trifosfato de Adenosina/farmacologia , Sequência de Aminoácidos , Sítios de Ligação , Fenômenos Químicos , Físico-Química , Cristalização , Transporte de Elétrons , Hidrólise , Substâncias Macromoleculares , Modelos Moleculares , Dados de Sequência Molecular , Estrutura Molecular , Molibdoferredoxina/química , Nitrogenase/metabolismo , Conformação Proteica , Difração de Raios X
5.
J Dent Res ; 97(4): 467-475, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29131694

RESUMO

Although many reports have demonstrated that ectopic pain develops in the orofacial region following tooth pulp inflammation, which often causes misdiagnosis and inappropriate treatment for patients with pulpitis, the precise mechanism remains unknown. In the present study, we hypothesized that the functional interaction between satellite glial cells and neurons mediated by interleukin 1ß (IL-1ß) in the trigeminal ganglion (TG) is involved in ectopic orofacial pain associated with tooth pulp inflammation. The digastric muscle electromyogram (D-EMG) activity elicited by capsaicin administration into the maxillary second molar tooth pulp was analyzed to evaluate the noxious reflex and was significantly increased in rats with inflammation of the maxillary first molar (M1) versus rats injected with saline. A significant increase in the expression of connexin43 (Cx43), a gap junction containing protein, was observed in activated satellite glial cells surrounding second molar-innervating neurons in the TG after M1 pulpitis. Daily administration of Gap26, a Cx43 mimetic peptide and inhibitor, in the TG significantly suppressed the enhancement of capsaicin-induced D-EMG activity and the percentage of Fluoro-Gold (FG)-labeled cells encircled by glial fibrillary acid protein-immunoreactive (IR) + Cx43-IR cells after M1 pulp inflammation ( P < 0.01). The percentage of FG-labeled cells encircled by glial fibrillary acid protein-IR + IL-1ß-IR cells, IL-1 type I receptor-IR cells labeled with FG, and TRPV1-IR cells labeled with FG significantly increased after M1 pulp inflammation ( P < 0.01). Daily administration of IL-1ra, an IL-1 receptor antagonist, into the TG significantly reduced the enhancement of capsaicin-induced D-EMG activity and the percentage of TRPV1-IR neurons labeled with FG after M1 pulp inflammation ( P < 0.01). The present findings suggest that satellite glial cell is activated in the TG via activated gap junctions composed of Cx43 following tooth pulp inflammation, which leads to the hyperactivation of remote neurons via IL-1ß mechanisms and results in ectopic tooth pulp pain in the adjacent tooth.


Assuntos
Interleucina-1beta/farmacologia , Neuroglia/metabolismo , Neurônios/metabolismo , Pulpite/patologia , Gânglio Trigeminal/metabolismo , Animais , Capsaicina , Conexina 43/metabolismo , Eletromiografia , Proteína Glial Fibrilar Ácida/metabolismo , Imuno-Histoquímica , Masculino , Ratos , Ratos Sprague-Dawley , Transdução de Sinais , Canais de Cátion TRPV/metabolismo
6.
Int J STD AIDS ; 16(9): 644-5, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16176638

RESUMO

Streptococcus pyogenes (the Lancefield group A streptococcus) is a cause of pharyngitis and impetigo. However, it has rarely been implicated as a sexually transmitted pathogen. We herein report two cases of severe balanitis due to S. pyogenes in sexually active men. It is postulated that penile cellulitis developed following the invasion of S. pyogenes through a traumatic abrasion acquired during fellatio performed by commercial sex workers. Both patients were treated successfully with oral administration of penicillin.


Assuntos
Balanite (Inflamação)/microbiologia , Balanite (Inflamação)/patologia , Streptococcus pyogenes/patogenicidade , Adulto , Humanos , Masculino , Pessoa de Meia-Idade , Infecções Estreptocócicas/microbiologia , Infecções Estreptocócicas/patologia
7.
J Biochem ; 86(4): 1067-80, 1979 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-115850

RESUMO

Staring from low molecular weight RNA obtained from rainbow trout (Salmo gairdnerii) liver, 5S ribosomal RNA (rRNA) was highly purified by successive chromatography on columns of DEAE-Sephadex A50 and Sephadex G100. Products of complete and partial digestions on this RNA with pancreatic ribonuclease (RNase A) [EC 3.1.4.22] and RNase T [EC 3.1.4.8] were isolated and sequenced by conventional and high-performance liquid chromatography (HPLC) procedures. The nucleotide sequence of this RNA thus established was compared with those of five other vertebrae 5S rRNAs, and the rates of base substitution per site per year were found to be nearly constant in these RNAs. The analyses of the partial digests of the trout 5S rRNA revealed several sites susceptible to RNase attack, which could be accounted for by the secondary structure model for eukaryotic 5S rRNAs proposed by Nishikawa and Takemura (1).


Assuntos
Fígado/análise , RNA Ribossômico , Animais , Sequência de Bases , Peso Molecular , Oligorribonucleotídeos/análise , RNA Ribossômico/isolamento & purificação , Ribonuclease T1 , Ribonucleases , Truta
8.
J Biochem ; 90(6): 1577-81, 1981 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7333996

RESUMO

The nucleotide sequence of 5S ribosomal RNA from plasmodia of the slime mold Physarum polycephalum was determined as pppGGAUGCGGC CAUACUAAGG 20 AGAAAGCACC 30 UCAUCCCGUC 40 CGAUCUGAGA 50 AGUUAAGCUC 60 CUUCAGGCGU 70 GGUUAGUACU 80 GGGGUGGGGG 90 ACCACCUGGG 100 AAUCCCACGU 110 GCUGCAUUCU 120 Uoh by chemical and enzymatic gel sequencing technics using 3' and 5' end-labeled RNA. This RNA is very different from 5S rRNA of the cellular slime mold Dictyostelium discoideum (36 nucleotides are different), and shows greater similarity to 5S rRNAs from Protozoa and Metazoa than to those from fungi.


Assuntos
Physarum/genética , RNA Ribossômico/genética , Sequência de Bases , Evolução Biológica , Ligação de Hidrogênio , Conformação de Ácido Nucleico
9.
J Biochem ; 89(5): 1663-6, 1981 May.
Artigo em Inglês | MEDLINE | ID: mdl-6268620

RESUMO

The nucleotide sequence of 5S rRNA from the fission yeast, S. pombe, has been established by post labeling procedures combined with cataloging RNase T1- and A-oligonucleotides derived from unlabeled 5S rRNA. The sequence consists of 119 nucleotides without a modified base and shows more dissimilarities (at 38 positions) from that of S. cerevisiae than from that of humans (at 33 positions).


Assuntos
Ascomicetos/análise , RNA Fúngico , RNA Ribossômico , Schizosaccharomyces/análise , Sequência de Bases , Endonucleases , Humanos , Ribonuclease T1 , Ribonuclease Pancreático , Ribonucleases , Saccharomyces cerevisiae/análise
10.
J Biochem ; 89(3): 717-22, 1981 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-7287637

RESUMO

A low molecular weight RNA fraction was obtained from the posterior silk glands of Bombyx mori. 5S rRNA was purified from this fraction by gel filtration on a column of Sephadex G-100 and electrophoresis on a discontinuous polyacrylamide gel devised for large scale preparation. The nucleotide sequence of this RNA was determined mainly by a chemical sequencing method on polyacrylamide gels using RNA labeled with [32P]pCp at the 3' terminus (1). An enzymatic sequencing method on gels using 32P-labeled RNA at the 5' end (2) and conventional sequence analyses of the complete digests of the unlabeled RNA with RNase T1 [EC 3.1.27.3] and RNase A [EC 3.1.27.5] were used for complete determination of the total sequence. 16 base substitutions were observed between B. mori and Drosophila melanogaster 5S rRNAs.


Assuntos
Bombyx/metabolismo , RNA Ribossômico/isolamento & purificação , Animais , Sequência de Bases , Eletroforese em Gel de Poliacrilamida , Glândulas Exócrinas/metabolismo , Peso Molecular , Conformação de Ácido Nucleico , Ribonucleases
11.
J Biochem ; 100(2): 369-74, 1986 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-3782056

RESUMO

In some amphibians and bony fishes, oocyte- and somatic-type 5S rRNA genes are expressed differently in oocytes and somatic cells. In order to determine at what stage of animal evolution this differential expression system appeared and how it is regulated, the sequences of oocyte and somatic 5S rRNAs from three invertebrates (sea urchin, sea hare, and silkworm) and two vertebrates (lamprey and chick) were analyzed. It was found that the oocyte 5S rRNA from lamprey consists of two components, while its somatic 5S rRNA consists of only one. In other animals, such differential expression of 5S rRNA in oocytes and somatic cells was not seen. A phylogenetic tree of 63 animal 5S rRNAs was constructed by means of the parsimony method, and the evolution of oocyte and somatic-type 5S rRNAs was discussed.


Assuntos
Oócitos/análise , RNA Ribossômico/genética , Animais , Aplysia , Sequência de Bases , Bombyx , Galinhas , Regulação da Expressão Gênica , Lampreias , RNA Ribossômico/análise , Ouriços-do-Mar
12.
J Biochem ; 88(5): 1449-56, 1980 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-6780539

RESUMO

By chromatography on columns of DEAE-Sephadex A-50 and Sephadex G-100, and electrophoresis on polyacrylamide gel, 5S rRNA was purified from a low-molecular-weight RNA fraction extracted from the total tissues of Lingula anatina. Complete digests of the 5S rRNA with RNase T1 [EC 3.1.4.8] and pancreatic RNase [EC 3.1.4.22] were sequenced by conventional column chromatography procedures. The nucleotide sequence of this RNA was determined mainly by a chemical method for sequencing the RNA 3' end-labeled with 32P (1), with the complement of the oligonucleotide catalog obtained by the complete RNase digestions of the RNA. By comparing the sequences of several invertebrate, vertebrate, and Chlorella 5S rRNAs, a phylogenic tree of the rRNAs was constructed and the time of divergence of Lingula was estimated.


Assuntos
Invertebrados/genética , RNA Ribossômico , Animais , Sequência de Bases , Evolução Biológica , Cromatografia por Troca Iônica , Eletroforese em Gel de Poliacrilamida , Ribonuclease T1/metabolismo , Ribonucleases/metabolismo
13.
J Biochem ; 86(4): 1081-8, 1979 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-115851

RESUMO

Conditions were established for the separation and quantitative determination of ribonucleosides, mono- and oligo-ribonucleotides by high-performance liquid chromatography (HPLC) on columns of AS-Pellionex SAX and AL-Pellionex WAX. By combining a high-speed UV spectrum monitor with an HPLC apparatus, products of RNase digestions of oligonucleotides and 5S ribosomal RNA (rRNA) were identified by measuring their UV spectra under continuous solvent flow, and also from their retention times on the columns (positions of elution). It took only 10 to 30 min for one chromatography run and required less than 0.01 A260 unit of sample per nucleotide material in each peak.


Assuntos
Sequência de Bases , Oligonucleotídeos , Oligorribonucleotídeos , RNA , Animais , Candida/análise , Cromatografia Líquida de Alta Pressão/métodos , Fígado/análise , Ribonuclease T1 , Ribonucleases , Truta
14.
Leuk Lymphoma ; 45(9): 1947-50, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15223661

RESUMO

Gamma/delta T-cell lymphoma (GDTL) is an uncommon lymphoma that was initially reported to involve only the liver and spleen. GDTL other than the hepatosplenic type is extremely rare. Frequent primary sites include skin and subcutaneous tissue, intestine, or nasal region. We report a case of GDTL of the omentum in a 54 year-old-man. The tumor cells are CD2-, CD3+, CD4-, CD5-, CD8+, CD56+, TIA-1+, granzyme B+/-. They expressed the identical phenotype of intestinal GDTL. The patient was treated with 2 courses of CHOP which comprised cyclophosphamide, doxorubicin, vincristine and prednisolone, and 3 courses of EPOCH which comprised etoposide, prednisolone, vincristine, cyclophosphamide and doxorubicin. However, he failed to obtain remission. During the fourth course of EPOCH, muscle weakness of the lower extremities developed and intracranial masses were observed by computed tomographic scan of the brain. Dissemination of lymphoma to the central nervous system was considered and it may be attributable to the expression of CD56 in this case. High dose methotrexate (HD-MTX) chemotherapy successfully eliminated the omental tumor and reduced the size of the intracranial masses, thus HD-MTX appears to be an effective treatment against GDTL.


Assuntos
Sistema Nervoso Central/patologia , Linfoma de Células T/patologia , Omento/patologia , Neoplasias Peritoneais/patologia , Humanos , Japão , Linfoma de Células T/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Neoplasias Peritoneais/tratamento farmacológico , Tomografia Computadorizada por Raios X
15.
Neurosurgery ; 28(6): 894-8, 1991 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2067617

RESUMO

The authors present three cases of dissecting aneurysms of the posterior inferior cerebellar artery (PICA). A literature search revealed only three previous cases. Analysis of these six cases showed a unique clinical picture. Three patients developed subarachnoid hemorrhage, and the other three had ischemia. All patients complained of occipital headache or neck pain, regardless of the initial symptoms. Heralding episodes were recorded in four cases. Angiography showed a characteristic fusiform dilatation of the PICA and a narrowing proximal to and distal to the lesion. Various surgical treatments were performed in five cases. Intraoperative observation showed a sausage-like swelling of the PICA or one of its branches with various discoloration depending on the age of the intramural clot. The outcomes were favorable.


Assuntos
Dissecção Aórtica/diagnóstico por imagem , Cerebelo/irrigação sanguínea , Adulto , Idoso , Dissecção Aórtica/complicações , Dissecção Aórtica/cirurgia , Artérias , Isquemia Encefálica/etiologia , Angiografia Cerebral , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Hemorragia Subaracnóidea/etiologia
16.
Hear Res ; 142(1-2): 89-101, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10748332

RESUMO

Cortical topographic map changes have been reported after profound drug-induced hearing loss in neonates, after progressive high-frequency hearing loss, and after mechanically induced lesions in the cochlea of adult animals. The present study demonstrates that exposure of 5-week-old kittens to a loud 6 kHz tone, producing mild to moderate high-frequency hearing loss, induces a profound reorganization of the frequency map in auditory cortex. In the reorganized cortical region, the frequency-tuning curves were of normal sharpness with near normal thresholds. Inhibitory tuning curve bandwidths were similar to those in control animals. Spontaneous activity in the reorganized part of the cortex was significantly increased. In contrast, the strength of the cross-correlation of the spontaneous activity of units recorded on different electrodes was the same in the normal and reorganized part. Minimum first-spike latency was significantly increased in trauma cats, largely for units at the dorsal side of the sampled region. Because most other neural response properties are normal in the reorganized part of cortex, sub-cortical topographic map changes are likely involved in producing the altered cortical topographic maps.


Assuntos
Envelhecimento/fisiologia , Córtex Auditivo/fisiopatologia , Perda Auditiva Provocada por Ruído/fisiopatologia , Plasticidade Neuronal , Animais , Limiar Auditivo , Mapeamento Encefálico , Gatos , Eletrofisiologia , Tempo de Reação , Valores de Referência
17.
Hear Res ; 150(1-2): 27-42, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11077191

RESUMO

We investigated how natural and morphed cat vocalizations are represented in primary auditory cortex (AI). About 40% of the neurons showed time-locked responses to major peaks in the vocalization envelope, 60% only responded at the onset. Simultaneously recorded multi-unit (MU) activity of these peak-tracking neurons on separate electrodes was significantly more synchronous during stimulation than under silence. Thus, the representation of the vocalizations is likely synchronously distributed across the cortex. The sum of the responses to the low and high frequency part of the meow, with the boundary at 2.5 kHz, was larger than the neuronal response to the natural meow itself, suggesting that strong lateral inhibition is shaping the response to the natural meow. In this sense, the neurons are combination-sensitive. The frequency-tuning properties and the response to amplitude-modulated tones of the MU recordings can explain the responses to natural, and temporally and spectrally altered vocalizations. Analysis of the mutual information in the firing rate suggests that the activity of at least 95 recording sites in AI would be needed to reliably distinguish between the nine different vocalizations. This suggests that a distributed representation based on temporal stimulus aspects may be more efficient than one based on firing rate.


Assuntos
Comunicação Animal , Córtex Auditivo/fisiologia , Neurônios/fisiologia , Vocalização Animal , Estimulação Acústica , Animais , Gatos , Discriminação Psicológica , Eletrofisiologia , Especificidade da Espécie , Fatores de Tempo
18.
Acta Otolaryngol ; 120(6): 750-6, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11099153

RESUMO

We hypothesized that moderate sensorineural hearing loss resulting from acoustic trauma would cause (i) a change in the cortical tonotopic map, (ii) an increase in spontaneous activity in the reorganized region and (iii) increased inter-neuronal synchrony within the reorganized part of the cortex. Five kittens were exposed to a 126 dB sound pressure limit tone of 6 kHz for 1 h at both 5 and 6 weeks of age. Recordings were performed 7-16 weeks after the exposure. Auditory brainstem response thresholds for frequencies above 12 kHz were increased by 30 dB on average relative to those in normal cats. Tonotopic maps in the primary auditory cortex were reorganized in such a way that the area normally tuned to frequencies of 10-40 kHz was now entirely tuned to 10 kHz. Spontaneous firing rates were significantly higher in reorganized areas than in normal areas. In order to test for changes in inter-neuronal synchrony, cross-correlation analysis was done on 225 single-unit pairs recorded in the traumatized cats. For the single- and dual-electrode pairs there was no significant difference in peak cross-correlation coefficients for the firings of simultaneously recorded cells between normal and reorganized areas. However, the percentage of correlations that differed significantly from zero was higher in the reorganized area than in the normal area. This suggests a potential correlation between cortical reorganization, increased spontaneous firing rate and inter-neuronal synchrony that might be related to tinnitus found in high-frequency hearing loss induced by acoustic trauma.


Assuntos
Estimulação Acústica/efeitos adversos , Córtex Auditivo/fisiopatologia , Cóclea/fisiopatologia , Perda Auditiva Provocada por Ruído/etiologia , Perda Auditiva Provocada por Ruído/fisiopatologia , Neurônios/fisiologia , Animais , Vias Auditivas/fisiopatologia , Limiar Auditivo/fisiologia , Gatos , Perda Auditiva Neurossensorial/diagnóstico , Perda Auditiva Neurossensorial/fisiopatologia , Plasticidade Neuronal/fisiologia , Zumbido/diagnóstico , Zumbido/fisiopatologia
19.
Biol Trace Elem Res ; 49(1): 67-73, 1995 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7577322

RESUMO

Calcification occurred in the kidney of streptozotocin (STZ)-induced diabetic rats fed a low-zinc diet. The deposits were stained by the von Kossa method and were detected intracellularly in the tubular cells, mainly in the cortico-medullar region. The deposits were found to be a heterogenous substance on electron microscopy. There were various sizes of deposits, and the surfactant was very much distorted. Many deposits grew up to bind small particles, and the core-like substance was observed in the center of the deposit. The component of the deposit was analyzed by an X-ray microanalyzer, and was found to be calcium and phosphorus. The ratio of calcium to phosphorus was 2.159, which coincided with the ratio of standard hydroxyapatite. From these observations, the deposit is believed to be hydroxyapatite. It is thought that the core is formed at first, many particles are then bound to the core, and deposits grow up.


Assuntos
Diabetes Mellitus Experimental/metabolismo , Durapatita/farmacocinética , Rim/metabolismo , Nefrocalcinose/embriologia , Zinco/deficiência , Animais , Glicemia/metabolismo , Cálcio/sangue , Cálcio/metabolismo , Cálcio/urina , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/complicações , Microanálise por Sonda Eletrônica , Masculino , Microscopia Eletrônica , Nefrocalcinose/etiologia , Ratos , Ratos Wistar
20.
Hiroshima J Med Sci ; 48(1): 25-9, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10213960

RESUMO

A 51-year-old woman, who had both aortitis syndrome (Takayasu arteritis) and IgA nephropathy, presented with hypertension, fever, a high erythrocyte sedimentation rate, high C-reactive protein and serum IgG levels, proteinuria, and renal dysfunction. Renal arteriography showed stenosis and poststenotic dilatation at the origin of the right renal artery, as well as tortuosity of the left renal artery branches and marked atrophy of the left kidney. Renal biopsy showed IgA nephropathy with deposits of IgA, C3, and fibrinogen in the glomeruli and arteriolosclerosis. The present patient had human leukocyte antigen (HLA)-B 52, which is reported to be related to the aortitis syndrome, as well as HLA-DR 4, which is possibly related to IgA nephropathy, suggesting that HLA status may be involved in the pathogenesis of both diseases.


Assuntos
Síndromes do Arco Aórtico/imunologia , Glomerulonefrite por IGA/imunologia , Antígenos HLA/imunologia , Adulto , Síndromes do Arco Aórtico/complicações , Síndromes do Arco Aórtico/diagnóstico por imagem , Síndromes do Arco Aórtico/patologia , Feminino , Glomerulonefrite por IGA/complicações , Glomerulonefrite por IGA/diagnóstico por imagem , Glomerulonefrite por IGA/patologia , Humanos , Radiografia
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