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1.
Clin Exp Immunol ; 203(2): 267-280, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33128773

RESUMO

The role of interleukin-22 (IL-22) in the pathogenesis or tissue repair in human tuberculosis (TB) remains to be established. Here, we aimed to explore the ex-vivo and in-vitro T helper 22 (Th22) response in TB patients and healthy donors (HD) induced by different local multi-drug-resistant (MDR) Mvcobacterium tuberculosis (Mtb) strains. For this purpose, peripheral blood mononuclear cells from drug-susceptible (S-TB) MDR-TB patients and HD were stimulated with local MDR strains and the laboratory strain H37Rv. IL-22 and IL-17 expression and senescent status were assessed in CD4+ and CD8+ cells by flow cytometry, while IL-22 amount was measured in plasma and culture supernatants by enzyme-linked immunosorbent assay (ELISA). We found lower IL-22 amounts in plasma from TB patients than HD, together with a decrease in the number of circulating T cells expressing IL-22. In a similar manner, all Mtb strains enhanced IL-22 secretion and expanded IL-22+ cells within CD4+ and CD8+ subsets, being the highest levels detected in S-TB patients. In MDR-TB, low systemic and Mtb-induced Th22 responses associated with high sputum bacillary load and bilateralism of lung lesions, suggesting that Th22 response could be influencing the ability of MDR-TB patients to control bacillary growth and tissue damage. In addition, in MDR-TB patients we observed that the higher the percentage of IL-22+ cells, the lower the proportion of programmed cell death 1 (PD-1)+ or CD57+ T cells. Furthermore, the highest proportion of senescent T cells was associated with severe lung lesions and bacillary load. Thus, T cell senescence would markedly influence Th22 response mounted by MDR-TB patients.


Assuntos
Pulmão/imunologia , Mycobacterium tuberculosis/imunologia , Linfócitos T Auxiliares-Indutores/imunologia , Tuberculose Resistente a Múltiplos Medicamentos/imunologia , Tuberculose Pulmonar/imunologia , Adulto , Antígenos de Bactérias/imunologia , Linfócitos T CD4-Positivos/imunologia , Antígenos CD57/imunologia , Linfócitos T CD8-Positivos/imunologia , Feminino , Humanos , Interferon gama/imunologia , Interleucina-17/imunologia , Interleucinas/imunologia , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/microbiologia , Pulmão/microbiologia , Masculino , Pessoa de Meia-Idade , Receptor de Morte Celular Programada 1/imunologia , Escarro/microbiologia , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia , Tuberculose Pulmonar/microbiologia , Adulto Jovem , Interleucina 22
2.
Phys Rev Lett ; 125(20): 201801, 2020 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-33258621

RESUMO

We report a measurement of the antineutrino rate from the fission of ^{235}U with the STEREO detector using 119 days of reactor turned on. In our analysis, we perform several detailed corrections and achieve the most precise single measurement at reactors with highly enriched ^{235}U fuel. We measure an IBD cross section per fission of σ_{f}=(6.34±0.06[stat]±0.15[sys]±0.15[model])×10^{-43} cm^{2}/fission and observe a rate deficit of (5.2±0.8[stat]±2.3[sys]±2.3[model])% compared to the model, consistent with the deficit of the world average. Testing ^{235}U as the sole source of the deficit, we find a tension between the results of lowly and highly enriched ^{235}U fuel of 2.1 standard deviations.

3.
Phys Rev Lett ; 121(16): 161801, 2018 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-30387650

RESUMO

The reactor antineutrino anomaly might be explained by the oscillation of reactor antineutrinos toward a sterile neutrino of eV mass. In order to explore this hypothesis, the STEREO experiment measures the antineutrino energy spectrum in six different detector cells covering baselines between 9 and 11 m from the compact core of the ILL research reactor. In this Letter, results from 66 days of reactor turned on and 138 days of reactor turned off are reported. A novel method to extract the antineutrino rates has been developed based on the distribution of the pulse shape discrimination parameter. The test of a new oscillation toward a sterile neutrino is performed by comparing ratios of cells, independent of absolute normalization and of the prediction of the reactor spectrum. The results are found to be compatible with the null oscillation hypothesis and the best fit of the reactor antineutrino anomaly is excluded at 97.5% C.L.

4.
Chem Commun (Camb) ; 52(43): 6977-80, 2016 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-27063187

RESUMO

A thiophene-based donor-acceptor phenothiazine dye has been functionalized with a peripheral glucose unit (PTZ-GLU) to bust its affinity to water and enhance dye-sensitized photogeneration of hydrogen. Compared to the corresponding alkyl derivative (PTZ-ALK), as well as the common hydrophilic triethylene glycol substitution (PTZ-TEG), the sugar derivative shows a lower contact angle; PTZ-GLU performed twice more efficient than PTZ-TEG in the photogeneration of hydrogen in terms of evolved gas and turnover number.


Assuntos
Corantes/química , Glucosídeos/química , Hidrogênio/química , Fenotiazinas/química , Catálise , Corantes/síntese química , Glucosídeos/síntese química , Luz , Nanocompostos/química , Fenotiazinas/síntese química , Platina/química , Titânio/química , Água/química , Molhabilidade
5.
Otolaryngol Head Neck Surg ; 114(6): 768-76, 1996 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8643301

RESUMO

Retinoids have recently become of interest to clinicians because of their ability to inhibit migration and proliferation of premalignant squamous cells while enhancing growth and proliferation of normal cells. An in vitro investigation was undertaken to determine whether retinoic acid exhibits similar inhibitory effects on cholesteatoma cells. Cholesteatoma specimens were obtained intraoperatively from 10 patients undergoing mastoidectomy or revision mastoidectomy for chronic ear disease. Cholesteatoma explant growth and en mass migration were observed daily, and topographic maps were constructed at various time intervals to quantity rate and direction of explant migration in the presence or absence of all-trans retinoic acid. Before all-trans retinoic acid administration, explants migrated very rapidly (1 to 2 mm/day). A maximum threefold inhibition of migratory rate occurred, with explants exposed to 0.1 micromol/L retinoic acid when compared with controls. A sixfold maximum inhibition was observed at higher retinoic acid concentrations (5 micromol/L). On removal of all-trans retinoic acid, twofold and fourfold increases in migratory rates were observed. The direction of explant migration varied significantly for long periods of time and appeared not to be affected by retinoic acid. This investigation suggests that all-trans retinoic acid has an inhibitory effect on cholesteatoma cell migration. Retinoids may have a role in controlling cholesteatoma disease in the future.


Assuntos
Movimento Celular/efeitos dos fármacos , Colesteatoma da Orelha Média/fisiopatologia , Tretinoína/farmacologia , Adesão Celular , Células Cultivadas , Colesteatoma da Orelha Média/patologia , Citoesqueleto , Relação Dose-Resposta a Droga , Humanos
6.
Otolaryngol Head Neck Surg ; 115(5): 458-63, 1996 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8903448

RESUMO

Cholesteatoma matrix and tympanic epithelia share the unique property of en mass migratory locomotion in vitro. Although this migratory behavior is not well understood, it is thought to be a major contributor to the pathogenesis and pathophysiology of cholesteatoma disease. We have surmised that en mass migration depends on tight calcium-dependent intercellular and substrate cellular adhesions. The purpose of this investigation was to determine the effects of a diminished extracellular calcium level on cholesteatoma migration and adhesion. Cholesteatoma matrixes obtained intraoperatively from patients undergoing mastoidectomies for chronic ear disease were cut into small fragments and grown in culture. When cultured specimens were exposed to low-calcium medium (0.14 mmol/L calcium), a greater than 10-fold reduction in the rate of migration was observed when compared with control values (1.8 mmol/L calcium). This reduction of migration returned to normal within 48 hours after extracellular calcium was replenished. Substrate cellular adhesion was also significantly reduced when cholesteatoma cells were grown in low-calcium medium. These observations were further supported by histomorphologic findings. Our findings suggest that calcium-dependent intercellular and substrate cellular adhesions are essential for cholesteatoma migration and adhesion. These studies further our understanding of the pathophysiology of cholesteatoma disease and may provide clues on how to better treat patients with this disease.


Assuntos
Cálcio/análise , Movimento Celular , Colesteatoma/fisiopatologia , Adesão Celular , Células Cultivadas , Orelha Média/fisiopatologia , Humanos , Técnicas In Vitro , Queratinócitos
7.
Otolaryngol Head Neck Surg ; 122(1): 91-5, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10629489

RESUMO

OBJECTIVES: It was previously shown that cholesteatoma migration in vitro is influenced by the calcium concentration of the culture medium. This study was designed to determine whether the calcium channel blocker verapamil affects cholesteatoma migration in vitro. METHODS: Cholesteatoma cells harvested from patients with chronic ear disease were grown in culture and were exposed to culture medium containing verapamil. The migration rate of the verapamil-exposed cells was compared with control rates. RESULTS: Verapamil at 300 microgram/L caused marked reduction in the rate of migration compared with control values. The migration rate returned to normal within 48 hours after verapamil was removed from the culture medium. Higher verapamil concentrations (500 microgram/L) caused complete detachment of the epithelial cells from the substrate within 24 hours. CONCLUSION: Our findings suggest that cholesteatoma migration in vitro is calcium channel dependent and can be reduced with calcium channel blockers such as verapamil.


Assuntos
Bloqueadores dos Canais de Cálcio/farmacologia , Colesteatoma da Orelha Média/fisiopatologia , Verapamil/farmacologia , Cálcio/fisiologia , Movimento Celular/efeitos dos fármacos , Movimento Celular/fisiologia , Células Cultivadas , Humanos , Técnicas In Vitro
8.
Ann Otol Rhinol Laryngol ; 108(9): 897-902, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10527283

RESUMO

Our objective was to discuss the management and outcome of abducens nerve palsy in patients with Gradenigo's syndrome. In a retrospective analysis of patients with Gradenigo's syndrome at a tertiary-care center in Houston, Texas, from 1987 to 1995, we identified 2 patients with Gradenigo's syndrome, both female. One had bilateral involvement, so that the total was 3 ears. Both patients had complete recovery of their abducens nerve palsy. In 2 ears with chronic mastoiditis, sixth nerve palsies failed to respond to medical therapy alone, but resolved after mastoidectomy with drainage of the petrous apex. We recommend that patients with Gradenigo's syndrome and evidence of chronic mastoiditis be treated with aggressive medical and surgical care.


Assuntos
Nervo Abducente/fisiopatologia , Antibacterianos/uso terapêutico , Paralisia/etiologia , Paralisia/fisiopatologia , Osso Petroso/diagnóstico por imagem , Infecções Estreptocócicas/complicações , Infecções Estreptocócicas/tratamento farmacológico , Adulto , Feminino , Humanos , Infusões Intravenosas , Processo Mastoide/cirurgia , Pessoa de Meia-Idade , Osso Petroso/microbiologia , Osso Petroso/cirurgia , Síndrome , Tomografia Computadorizada por Raios X
9.
Clin Nucl Med ; 23(3): 163-4, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9509931

RESUMO

Presented is a case in which there was significant accumulation of In-111 Octreotide in brain infarcts. It is likely that the accumulation was nonspecific and due to breakdown of the blood-brain barrier.


Assuntos
Infarto Cerebral/diagnóstico por imagem , Radioisótopos de Índio , Octreotida/análogos & derivados , Idoso , Encéfalo/diagnóstico por imagem , Humanos , Masculino , Cintilografia , Tomografia Computadorizada por Raios X
11.
Am J Otolaryngol ; 15(5): 336-43, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-7978037

RESUMO

Paraneoplastic syndromes are distinct physiological disorders of malignancy that occur remote from a tumor site. A review of a number of paraneoplastic syndromes occurring in patients with head and neck cancer has been discussed. These syndromes can produce life-threatening sequelae in the patient with cancer. Understanding these syndromes may provide important clinical information to assist in the early detection of occult malignancy and in reducing the occurrence of tumor-associated morbidity.


Assuntos
Neoplasias de Cabeça e Pescoço/complicações , Síndromes Paraneoplásicas/etiologia , Carcinoma de Células Escamosas/complicações , Neoplasias de Cabeça e Pescoço/secundário , Humanos , Linfoma/complicações
12.
J Biol Chem ; 266(6): 3987-94, 1991 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-1671676

RESUMO

A sensitive and reproducible method to measure relative levels of polymerized and soluble tubulin in cells has been developed. This method involves metabolically labeling cells with radioactive amino acids followed by lysis in a microtubule-stabilizing buffer, centrifugation to separate soluble from polymerized tubulin, resolution of the proteins in each fraction by two-dimensional gel electrophoresis, and quantitation of the tubulin by liquid scintillation counting of spots excised from the gel. Several buffers were evaluated for their reproducibility and efficacy in preserving the state of in vivo microtubule assembly at the time of cell lysis, and the ability of the technique to measure drug-induced changes in tubulin polymerization was determined. Results using this method indicate that Chinese hamster ovary cells maintain approximately 40% of the cellular tubulin in an assembled form. Dose-dependent decreases in tubulin polymerization could be measured in Colcemid-treated cells, while dose-dependent increases in assembly were measured in taxol-treated cells. The results with taxol indicate that, following the increase in microtubule polymerization, there is a time-dependent bundling of microtubules that occurs without further increases in the extent of tubulin assembly. Examination of drug-resistant Chinese hamster ovary cells reveals that Colcemid-resistant mutants maintain more tubulin in the polymerized state (approximately 50%), while taxol-resistant mutants maintain less assembled tubulin (about 28%). Similar changes occur regardless of whether the mutant cells have an alteration in alpha- or in beta-tubulin. A model to explain these results is discussed.


Assuntos
Mitose/efeitos dos fármacos , Tubulina (Proteína)/metabolismo , Alcaloides/farmacologia , Animais , Autorradiografia , Células Cultivadas , Cricetinae , Cricetulus , Demecolcina/farmacologia , Resistência a Medicamentos/genética , Eletroforese em Gel Bidimensional , Imunofluorescência , Microtúbulos/efeitos dos fármacos , Mutação , Paclitaxel , Polímeros
13.
Am J Otolaryngol ; 15(4): 292-6, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-7978030

RESUMO

Teratomas of the head and neck are uncommon. They are composed of tissues from all three germ layers with varying degrees of differentiation. They arise from pluripotent stem cells and ectopic embryonic nongerm cells. Head and neck teratomas most commonly emerge during the neonatal period and are associated with airway obstruction and high rates of mortality in untreated patients. The tumors are usually benign, but when found during adulthood, they have a high incidence of malignancy. The most common site of occurrence is the cervical region and the nasopharynx. We presented a rare case of teratoma originating from the base of the tongue. This case is an example of the development of teratoma by pinching off of remnants of the three germinal areas, which become marginated in the normal migratory pathway as the different structures of the head and neck develop. The remnants developed into the predetermined organ systems, giving rise to the heterotopic tissues encountered. The recommended treatment for head and neck teratomas is surgical excision. When a patient is experiencing respiratory difficulty, establishment of an airway is a priority.


Assuntos
Neoplasias de Cabeça e Pescoço/diagnóstico , Teratoma/diagnóstico , Pré-Escolar , Neoplasias de Cabeça e Pescoço/cirurgia , Humanos , Masculino , Sistema Estomatognático/embriologia , Teratoma/cirurgia , Neoplasias da Língua/diagnóstico , Neoplasias da Língua/cirurgia
14.
J Biol Chem ; 263(28): 14566-73, 1988 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-2844777

RESUMO

The generation of Chinese hamster ovary cell lines that express assembly defective forms of beta-tubulin were isolated using selections based on reversion of conditional lethal or drug resistance phenotypes. Two such cell lines, D2 and 6H3, were chosen for further characterization because they contain beta-tubulin polypeptides that exhibit decreases in apparent molecular weight on two-dimensional gel electrophoresis. Analysis of the nucleic acid from these cell lines using both Southern and Northern procedures suggests a deletion in one of the beta-tubulin genes in each cell line. Localization of the missing sequence in D2 was first determined by tryptic peptide mapping by high performance liquid chromatography. Subsequently, the assignment was confirmed by constructing appropriate subclones of a wild type Chinese hamster ovary beta-tubulin cDNA for Southern analysis to demonstrate a failure to recognize characteristic hybridization patterns of the mutant tubulin gene. In the other revertant, 6H3, the deletion was detected on a Northern blot by differential hybridization of a 3' fragment of the cDNA to the beta-tubulin messages. The results indicate that D2 has an internal deletion whose approximate limits extend from amino acid residues 250 through 345. Cell line 6H3 has a deletion that begins near amino acid residue 330 and extends into the 3'-untranslated region of the gene.


Assuntos
Mutação , Tubulina (Proteína)/genética , Animais , Northern Blotting , Southern Blotting , Linhagem Celular , DNA/genética , Enzimas de Restrição do DNA , Metionina/metabolismo , Microtúbulos/metabolismo , Fragmentos de Peptídeos/análise , Mapeamento de Peptídeos , RNA Mensageiro/genética , Tripsina , Tubulina (Proteína)/biossíntese
15.
Anal Biochem ; 184(1): 28-34, 1990 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2321756

RESUMO

Methods for examining altered regions in unstable mutant proteins are described. The strategy is illustrated using assembly defective Chinese hamster beta-tubulin subunits that are rapidly degraded in the cell. These unstable proteins are metabolically labeled to high specific activity and isolated as spots on two-dimensional gels. Conditions for the generation of tryptic peptides from gel pieces containing beta-tubulin and their subsequent resolution by HPLC have been worked out. Through a combination of dual labeling with various tritiated amino acids and [35S]methionine as well as partial sequence analysis, the identification of several HPLC peaks with the known sequence of beta-tubulin has been accomplished. This technique should greatly aid attempts to map the sites of mutational alterations in beta-tubulin polypeptides, and the general strategy should be readily applicable to other mutant proteins.


Assuntos
Metionina/análise , Fragmentos de Peptídeos/isolamento & purificação , Tubulina (Proteína)/análise , Sequência de Aminoácidos , Animais , Linhagem Celular , Cromatografia Líquida de Alta Pressão/métodos , Cricetinae , Feminino , Mutação , Ovário/citologia , Mapeamento de Peptídeos , Tripsina/metabolismo , Tubulina (Proteína)/isolamento & purificação
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