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1.
Phys Chem Chem Phys ; 22(16): 9098-9109, 2020 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-32300765

RESUMO

Li and Mn-rich Li1+xNiyCozMnwO2 (LMR-NMC, 0 < x < 0.2; w > 0.5) materials remain commercially relevant owing to their high specific capacity. Due to this stoichiometry, their synthesis forms always at least two phases: monoclinic Li2MnO3 and rhombohedral LiNiaCobMncO2 (a = b = c = 1) layered moieties. However, a complete understanding of their complex crystal structure has not yet been fully realized. The monoclinic phase may become electrochemically active only at high potentials (>4.6 V vs. Li). To complicate matters even more, it has been shown that the electrochemical performance of these materials, having formally the same stoichiometry, can vary with the chosen method of material synthesis. Identification of the chemical and/or structural reasons for these variations in performance is crucial to ensure the promotion of these important cathode materials towards a practical use. Yet most methods of analysis cannot distinguish the subtle, localized variations that account for such differences. Here, solid state 6,7Li NMR was found to be successful in identifying several distinctions between compounds with identical chemical formulae. Many distinctions can be made, and even suggested to account for some of the differences in the electrochemical behaviors noted for the differently prepared materials.

2.
Mech Ageing Dev ; 22(3-4): 209-18, 1983.
Artigo em Inglês | MEDLINE | ID: mdl-6605463

RESUMO

The effect of thymus humoral factor (THF) on T cell growth factor (TCGF) production by T cells and the association between splenic macrophages and T cells from young (2-3 months) and old (20-24 months) mice in this respect were studied. Splenocytes were divided into three groups: stimulated with concanavalin A (Con A); preincubated with THF and then stimulated with Con A; or stimulated with Con A and thereafter incubated with THF. These cells were then examined for production of TCGF. Cells treated with Con A and THF as described above were passed on nylon wool to enrich T cell populations and added to mitogen-sensitized (Con A or lipopolysaccharide) adherent splenocytes of old and young mice in the following combinations: young adherent and young T cells; young adherent and old T cells; old adherent and young T cells; and old adherent and old T cells. The results demonstrated that: (A) cells of old mice produced less TCGF than the young; (B) preincubation of splenocytes or nylon-wool enriched T cells with THF increased the production of TCGF consistently in young mice, whereas in the old a significant increase was observed only in some cases; (C) depressed TCGF activity was observed when treatment with THF to splenocytes or nylon-wool enriched T cells from young and old mice was performed after Con A stimulation, and this was also more pronounced in the young; (D) the reduced level of TCGF in the old seemed to be related to a lesion in the T cell compartment, since adherent cells from old and young mouse spleens could support TCGF production by T cells from young mice and not from old.


Assuntos
Envelhecimento , Interleucina-2/imunologia , Linfócitos T/imunologia , Hormônios do Timo/imunologia , Animais , Concanavalina A/farmacologia , Imunidade Celular , Interleucina-2/análise , Ativação Linfocitária , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Baço/imunologia , Hormônios do Timo/análise
3.
J Endocrinol ; 101(2): 149-53, 1984 May.
Artigo em Inglês | MEDLINE | ID: mdl-6716032

RESUMO

A study was carried out to determine the effect on lymphocytic cortisol metabolism (LCM) of plasma from 62 patients with diffuse thyrotoxic goitre (DTG), 14 patients with toxic nodular goitre (TNG) and ten hypothyroid patients. Plasma of 33 healthy donors served as controls. A known concentration of human lymphocytes was incubated with cortisol in media containing 50% phosphate-buffered saline (PBS) and 50% of one of the following additions: (1) PBS, (2) homologous plasma (HP), (3) heterologous plasma, (4) plasma from DTG patients, (5) plasma from TNG patients, (6) plasma from hypothyroid patients, (7) PBS and HP to which L-thyroxine (T4) and triiodothyronine (T3) had been added separately and as a mixture up to a concentration ten times the normal, (8) boiled HP and (9) boiled DTG plasma. Plasma from hypothyroid patients gave an LCM-enhancing effect (LCMEE) similar to that of HP. The plasma of DTG and TNG patients had a markedly lesser effect on LCM than did HP. The T4 and T3 had no additional effect when added to PBS or HP. Boiling of HP and DTG plasma resulted in a similar decrease in LCMEE. The findings of this study raise the possibility of the existence of a factor inhibiting LCMEE in the plasma of thyrotoxic patients.


Assuntos
Hidrocortisona/sangue , Hipertireoidismo/sangue , Linfócitos/metabolismo , Adolescente , Adulto , Idoso , Feminino , Bócio Nodular/sangue , Humanos , Hipotireoidismo/sangue , Técnicas In Vitro , Masculino , Pessoa de Meia-Idade , Tiroxina/farmacologia , Tri-Iodotironina/farmacologia
4.
Chest ; 80(3): 259-63, 1981 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7273875

RESUMO

Two patients under long-term surveillance showed the similar clinical features of low-grade fever, scanty productive cough, progressive dyspnea, and roentgenologic findings of lung infiltrates. Both patients responded only to systemic corticosteroid therapy and suffered relapses when it was discontinued. In one patient, who was found to be IgA-deficient, the pulmonary disease followed an episode of subacute thyroiditis; in this patient the intake of cephalosporin and subsequent rechallenge with the drug aggravated the disease. Needle biopsies in both patients showed the features of organizing intra-alveolar pneumonia. The histopathologic findings and their relation to the clinical symptoms are discussed.


Assuntos
Fibrose Pulmonar/diagnóstico , Corticosteroides/uso terapêutico , Idoso , Biópsia por Agulha , Cefalosporinas/efeitos adversos , Feminino , Humanos , Pulmão/diagnóstico por imagem , Masculino , Alvéolos Pulmonares/citologia , Alvéolos Pulmonares/diagnóstico por imagem , Alvéolos Pulmonares/patologia , Fibrose Pulmonar/diagnóstico por imagem , Fibrose Pulmonar/tratamento farmacológico , Fibrose Pulmonar/etiologia , Radiografia , Testes de Função Respiratória , Tireoidite/complicações
5.
J Am Geriatr Soc ; 34(9): 627-32, 1986 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-3734309

RESUMO

Folate levels of serum and red blood cells (RBC) and vitamin B12 serum levels were investigated in 326 urban chronically ill elderly ambulatory patients and 41 healthy young control subjects. Two laboratory methods were used for investigating the folate levels, the microbiologic assay (MBA) with Lactobacillus casei and radioassay (RA). Serum and RBC samples of 326 patients were tested by the folate MBA and 270 of the same samples by the RIA methods. In the MBA 6.8% of the patients and 12.2% of controls had low levels of folate RBC (less than 200 ng/mL) and 1.8% of patients and 4.8% of controls had low serum folate levels (less than 5 ng/mL). All of the patients with the low folate levels had normal hematologic findings and no clinical symptoms of folate deficiency. In the RIA method, all of the patients and almost all of the control subjects (except one) had normal folate levels. Ten of the patients (3%) had low levels of serum vitamin B12 (less than 200 pg/mL). They were hematologically normal. They had normal Schilling tests and normal vitamin B12 dietary intake. Their RBC folate levels were normal and even somewhat higher. Forty percent of these patients had macular degeneration of the eyes. The data indicate the superiority of the RA method over the MBA and bring into question the accuracy of previous studies. The data furnish further evidence that a low vitamin B12 level in the elderly is not necessarily a true vitamin B12 deficiency and raise the possibility of an association between low B12 serum levels and macular degeneration of the eyes.


Assuntos
Envelhecimento , Doença Crônica , Ácido Fólico/sangue , Vitamina B 12/sangue , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Radioimunoensaio , População Urbana
6.
J Hum Hypertens ; 18(5): 301-5, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15103309

RESUMO

Orthostatic hypotension (OH) is a common finding in the elderly. OH is defined as a fall of at least 20 mmHg in systolic blood pressure (BP) and/or 10 mmHg in diastolic BP upon assuming an upright posture. Some patients exhibit a fall in BP of less than the defined OH upon standing. The aim of this study was to estimate the prevalence of BP changes not defined as OH among elderly in-patients and to assess the relationship between these changes in the morning and the occurrence of OH during the day. Postural BP measurements were performed in 502 in-patients; in the morning, early afternoon, and in the evening. We defined intermediate postural drop (ID) in BP as a decrease of 10-19 mmHg in systolic BP and/or of 5-9 mmHg in diastolic BP. We observed that OH and ID occurred in 39.2 and 18.5% of the measurements in the morning, respectively. The prevalence of OH and ID was lower in the evening than in the morning (P<0.05) and afternoon (P<0.005). Postural BP changes in the morning correlated with those occurring later in the day. Patients who had ID in the morning had a 57% probability of having OH later during the day. In conclusions, ID is prevalent in elderly in-patients. ID in the morning predicts OH later in the day. Thus, postural BP drops below the OH range may be an important finding in the geriatric population.


Assuntos
Pressão Sanguínea , Ritmo Circadiano , Hipotensão Ortostática/diagnóstico , Idoso , Diástole , Feminino , Frequência Cardíaca , Humanos , Hipotensão Ortostática/epidemiologia , Hipotensão Ortostática/fisiopatologia , Pacientes Internados/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Postura , Prevalência , Probabilidade , Sístole
7.
Am J Med Sci ; 270(3): 523-4, 1975.
Artigo em Inglês | MEDLINE | ID: mdl-1211412

RESUMO

In a 47-year-old healthy male, the syndrome of overwhelming pneumococcal sepsis, associated with diffuse intravascular clotting, appeared 25 years after a post-traumatic splenectomy. Although no other disease was present, the course was fulminant and the outcome fatal. Splenectomy for any condition and in all ages, augments the risk to severe pneumococcal infection.


Assuntos
Infecções Pneumocócicas/etiologia , Complicações Pós-Operatórias , Sepse/etiologia , Esplenectomia , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Tempo
8.
Am J Med Sci ; 272(3): 327-30, 1976.
Artigo em Inglês | MEDLINE | ID: mdl-1015512

RESUMO

A woman hospitalized because of attempted suicide with diazepam tablets was found to have hypercalcemia and other signs of hyperparathyroidism. Electroencephalogram indicated a brain lesion which was confirmed by a brain scan and angiogram. The hypercalcemia persisted after removal of the meningioma and serum levels of calcium returned to normal only after a parathyroid adenoma was removed during an additional intervention. This association of meningioma with hyperparathyroidism is unique in the literature. The difficulties of diagnosis resulting from the neuropsychiatric symptoms common to the two disorders are discussed.


Assuntos
Adenoma/complicações , Neoplasias Encefálicas/complicações , Meningioma/complicações , Neoplasias das Paratireoides/complicações , Feminino , Humanos , Pessoa de Meia-Idade
9.
Am J Med Sci ; 319(5): 338-9, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10830559

RESUMO

Clostridium difficile-related diarrhea and colitis are common health problems, especially in elderly, frail hospitalized patients. The drug of choice is metronidazole, which can be associated, in long or high doses, with neurotoxic side effects. We report convulsions induced by short-term metronidazole therapy used in conventional doses for Clostridium difficile colitis in an elderly patient with chronic renal failure.


Assuntos
Anti-Infecciosos/efeitos adversos , Enterocolite Pseudomembranosa/tratamento farmacológico , Falência Renal Crônica/complicações , Metronidazol/efeitos adversos , Convulsões/induzido quimicamente , Idoso , Feminino , Humanos
10.
Am J Med Sci ; 277(2): 207-13, 1979.
Artigo em Inglês | MEDLINE | ID: mdl-37733

RESUMO

Jaundice with evidence of hepatocellular damage of moderate severity was observed in a patient who received methyldopa. The diffuse mononuclear infiltration of the liver tissue was found to consist of 90% E-rosette-forming cells. Peripheral lymphocytes gave a markedly positive macrophage migration inhibition (MIF) test against methyldopa. The number of T lymphocytes in the peripheral blood was at the lower limit of normal but they proved to be functionally inactive, as demonstrated by the results of a local xenogeneic graft-vs-host reaction test. The liver disease was associated with hyperglobulinemia, a decrease of the third and fourth components of complement and the presence of incomplete erythrocytic antibodies, leukoagglutinins, antinuclear factor, and smooth muscle antibody. Follow-up after discontinuation of the drug revealed a gradual return to normal of liver function and MIF tests, normalization of cellular immunity, and disappearance of the humoral antibodies. It is assumed that sensitization by methyldopa triggered the autoaggressive phenomena and their ultimate manifestation in the liver.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/imunologia , Fígado/efeitos dos fármacos , Metildopa/efeitos adversos , Biópsia por Agulha , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Doença Hepática Induzida por Substâncias e Drogas/patologia , Teste de Coombs , Feminino , Reação Enxerto-Hospedeiro , Humanos , Imunidade , Imunidade Celular , Testes de Função Hepática , Fatores Inibidores da Migração de Macrófagos , Macrófagos/imunologia , Pessoa de Meia-Idade , Papaína , Formação de Roseta , Linfócitos T/imunologia
11.
Clin Geriatr Med ; 1(4): 711-28, 1985 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-3913517

RESUMO

Folate deficiency has become a popular topic in geriatric literature recently. There are two main reasons for this interest: folate deficiency is prevalent among the elderly population, and many chronically ill elderly patients suffer from hematologic or neuropsychiatric disorders of which folate deficiency may be one of the causal factors. This article discusses serum, erythrocyte, and liver folate levels, the neurologic and psychiatric symptoms associated with folate deficiency, folate nutrition and absorption in the elderly, and the interrelationships of folate with vitamins, iron, and zinc.


Assuntos
Deficiência de Ácido Fólico/fisiopatologia , Ácido Fólico/metabolismo , Idoso , Demência/etiologia , Interações Medicamentosas , Eritrócitos/metabolismo , Ácido Fólico/sangue , Deficiência de Ácido Fólico/complicações , Humanos , Absorção Intestinal , Ferro/metabolismo , Transtornos Mentais/etiologia , Manifestações Neurológicas , Fenômenos Fisiológicos da Nutrição , Valores de Referência , Vitaminas/metabolismo , Zinco/metabolismo
12.
Arch Gerontol Geriatr ; 26(3): 227-34, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-18653139

RESUMO

A total of 105 elderly patients hospitalized for acute infectious disease were classified into prehospital demented and non demented groups and into dependent and independent groups. Demographic data, clinical and biological parameters and previous health problems were recorded. There was a significant difference between the two cognitive and functional groups in complications, length of stay, dehydration, confusion, albumin and hemoglobin. A logistic regression analysis taking into account the epidemiologic parameters, functional and cognitive status and the medical health problems has shown that only age, dementia and previous neurologic disease (mainly stroke) are independent risk factors for confusion and complications. Thus, the prehospitalization function, cognitive status and previous neurologic disease in elderly patients with acute infections may have a predictive and prognostic value.

13.
ACS Appl Mater Interfaces ; 2(7): 1999-2004, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20614915

RESUMO

Ultrasound irradiation was applied as a "throwing stones" technique for coating cotton bandages with MgO and Al(2)O(3) commercially obtained nanoparticles. The homogeneous distribution of the nanoparticles without any aggregation on the fabrics was demonstrated. The antibacterial activities of the MgO/Al(2)O(3)-fabric nanocomposite were tested against Escherichia coli (Gram negative) and Staphylococcus aureus (Gram positive) cultures. A significant bactericidal effect, even in a concentration <1% (by weight), was detected.


Assuntos
Antibacterianos/química , Escherichia coli/crescimento & desenvolvimento , Nanocompostos/química , Staphylococcus aureus/crescimento & desenvolvimento , Têxteis , Ultrassom , Óxido de Alumínio/química , Óxido de Magnésio/química
20.
Gerontology ; 46(6): 323-7, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11044787

RESUMO

BACKGROUND: Myelodysplastic syndrome (MDS) is predominantly a disease of old age. The number of MDS cases diagnosed over the last 20 years has risen substantially due to increased awareness and improved geriatric care. Although MDS is increasingly diagnosed, the prevalence and prognosis of early-stage affected elderly are not completely known. OBJECTIVE: To evaluate the prevalence, characteristics and prognosis of newly diagnosed MDS patients hospitalized in an acute and subacute geriatric department. METHODS: Between 1993 and 1996, 3,275 patients hospitalized in the geriatric department of a teaching hospital for acute care or short-term rehabilitation were investigated for unexplained hematological abnormalities. Demographic, chronic comorbidities, cause of hospitalization, functional and cognitive status, hematological and other laboratory parameters were collected. RESULTS: Two hundred and forty-five (7.5%) patients had unexplained cytopenia, macrocytosis or monocytosis, of whom 37 (15%) were diagnosed as having MDS. Only 9 patients were hospitalized for evaluation of anemia, 28 for infections, cardiac, cerebrovascular events and other causes. Thirty-four patients had refractory anemia (RA), two had RA with ringed sideroblasts and 1 had RA with an excess of blasts (RAEB). The follow-up period was up to 70 months. No differences were found between demented and cognitively normal patients in age, sex, comorbidities or laboratory parameters. Comparison of survival curves (excluding the RAEB case) according to demographic, clinical and hematological parameters has shown that only dementia adversely affects survival, compared to cognitively normal patients (p = 0.024). CONCLUSIONS: MDS of the RA type is a common and incidental finding in older hospitalized patients. It is a frequent cause of anemia and other hematological abnormalities but has less significance on survival rates than dementia, although its full impact remains to be determined.


Assuntos
Anemia Refratária com Excesso de Blastos/mortalidade , Demência/mortalidade , Serviços de Saúde para Idosos/estatística & dados numéricos , Hospitalização/estatística & dados numéricos , Doença Aguda , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Masculino , Prevalência , Prognóstico , Cuidados Semi-Intensivos/estatística & dados numéricos , Taxa de Sobrevida
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