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1.
Plant Biol (Stuttg) ; 24(4): 618-626, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35114051

RESUMO

Cadmium (Cd) toxicity reduces growth and yield of crops grown in metal-polluted sites. Research was conducted to estimate the potential of hydrogen sulphide (H2 S) to mitigate toxicity caused by Cd in fenugreek seedlings (Trigonella foenum-graecum L.). Different concentrations of CdCl2 (Cd1-1 mM, Cd2-1.5 mM, Cd3-2mM) and H2 S (HS1-100 µM, HS2-150 µM, HS3-200 µM) were assessed. Seeds of fenugreek were primed with sodium hydrosulphide (NaHS), as H2 S donor. Seedlings growing in Cd-spiked media treated with H2 S were harvested after 2 weeks. Cd stress affected growth of fenugreek seedlings. Cd toxicity decreased leaf relative water content (LRWC), intercellular CO2 concentration, net photosynthesis, stomatal conductance and transpiration. However, application of H2 S significantly improved seedling morphological attributes by increasing the activity of antioxidant enzymes, i.e. APX, CAT and SOD, in Cd-contaminated soil. H2 S treatment also regulated phenolic and flavonoid content. H2 S-induced biosynthesis of spermidine (Spd) and putrescine (Put) could account for the enhancement of growth and physiological performance of fenugreek seedlings under Cd stress. H2 S treatment also reduced H2 O2 production (38%) and electrolyte leakage (EL, 51%) in seedlings grown in different concentrations of Cd. It is recommended to evaluate the efficacy of H2 S in alleviating Cd toxicity in other crop plants.


Assuntos
Sulfeto de Hidrogênio , Trigonella , Antioxidantes/metabolismo , Cádmio/toxicidade , Peróxido de Hidrogênio , Sulfeto de Hidrogênio/farmacologia , Estresse Oxidativo , Poliaminas , Plântula , Trigonella/metabolismo
2.
Am J Physiol Renal Physiol ; 315(6): F1833-F1842, 2018 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-30207172

RESUMO

The p66ShcA protein controls cellular responses to oxidative stress, senescence, and apoptosis. Here, we test the hypothesis that aging phenotype(s) commonly associated with the broad category of chronic kidney disease are accelerated in diabetic kidneys and linked to the p66ShcA locus. At the organ level, tissue stem cells antagonize senescent phenotypes by replacing old dysfunctional cells. Using established methods, we isolated a highly purified population of stem cell antigen-1-positive mesenchymal stem cells (Sca-1+ MSCs) from kidneys of wild-type (WT) and p66 knockout (p66 KO) mice. Cells were plated in culture medium containing normal glucose (NG) or high glucose (HG). Reactive oxygen species (ROS) metabolism was substantially increased in WT MSCs in HG medium in association with increased cell death by apoptosis and acquisition of the senescent phenotype. DNA microarray analysis detected striking differences in the expression profiles of WT and p66 KO-MSCs in HG medium. Unexpectedly, the analysis for p66 KO-MSCs revealed upregulation of Wnt genes implicated in self-renewal and differentiation. To test the in vivo consequences of constitutive p66 expression in diabetic kidneys, we crossed the Akita diabetic mouse with the p66KO mouse. Homozygous mutation at the p66 locus delays or prevents aging phenotype(s) in the kidney that may be precursors to diabetic nephropathy.


Assuntos
Envelhecimento/metabolismo , Nefropatias Diabéticas/metabolismo , Rim/metabolismo , Células-Tronco Mesenquimais/metabolismo , Proteína 1 de Transformação que Contém Domínio 2 de Homologia de Src/metabolismo , Fatores Etários , Envelhecimento/genética , Envelhecimento/patologia , Animais , Apoptose , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Senescência Celular , Nefropatias Diabéticas/genética , Nefropatias Diabéticas/patologia , Modelos Animais de Doenças , Glucose/metabolismo , Rim/patologia , Células-Tronco Mesenquimais/patologia , Camundongos Knockout , Fenótipo , Espécies Reativas de Oxigênio/metabolismo , Proteína 1 de Transformação que Contém Domínio 2 de Homologia de Src/deficiência , Proteína 1 de Transformação que Contém Domínio 2 de Homologia de Src/genética , Nicho de Células-Tronco , Via de Sinalização Wnt
3.
J Contemp Dent Pract ; 2(2): 93-7, 2001 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-12167937

RESUMO

This 24-year old black female presented with a chief complaint of this gingival mass. She states she first noticed the lesion about three months ago and it has gotten progressively larger. What is your diagnosis?


Assuntos
Hemorragia Gengival/diagnóstico , Doenças Mandibulares/diagnóstico , Adulto , Carcinoma de Células Escamosas/diagnóstico , Diagnóstico Diferencial , Feminino , Fibroma Ossificante/diagnóstico , Granuloma/diagnóstico , Humanos , Gravidez
4.
Clin Cancer Res ; 5(7): 1723-30, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10430075

RESUMO

A Phase I and pharmacological study of paclitaxel administered as an outpatient, 3-h i.v. infusion just before a 5-day regimen of daily cisplatinum (CP) and a continuous infusion of 5-fluorouracil (5-FU) was performed in patients with advanced solid tumors. A secondary objective was to determine the objective response rate to this regimen. Forty-two patients were enrolled and were evaluable for toxicities. Eighteen patients were previously untreated, whereas the rest had received prior treatment with radiation (J. H. Schiller et al., J. Clin. Oncol., 12: 241-248, 1994), chemotherapy (M. J. Kennedy et al., Clin. Cancer Res., 4: 349-356, 1998), or both modalities (J. H. Schiller et al., J. Clin. Oncol., 12: 241-248, 1994). The paclitaxel dose was escalated from 100-135-170-200-225 to 250 mg/m2, whereas i.v. 5-FU and CP doses were fixed at 1.0 g/m2/day continuous infusion and 20 mg/m2/day, respectively, daily for 5 days. Granulocyte colony-stimulating factor (G-CSF; 5 microg/kg/day) was administered s.c. from day 6, routinely after 250 mg/m2 dose of paclitaxel or after a lower dose of paclitaxel if ANC <500/microl or febrile neutropenia was observed. Patients were treated every 28 days. Plasma and urine samples were collected to determine the pharmacokinetics of paclitaxel. In previously untreated patients, the maximally tolerated dose of paclitaxel in the drug regimen was determined to be 170 mg/m2 without and 250 mg/m2 with G-CSF support. At the higher dose level, mucositis and thrombocytopenia were dose-limiting. In previously treated patients, these toxicities were observed at all dose levels of paclitaxel > or =135 mg/m2. With increasing doses of paclitaxel, a disproportionate increase in the peak concentrations, as well as the area under plasma concentration time-curve, was seen. This nonlinearity was due to saturable total body clearance and volume of distribution of paclitaxel (P < 0.001). The apparent plasma elimination half-life was unaffected by the dose of paclitaxel. CP and 5-FU had no apparent effect on the metabolism of paclitaxel. Among 32 patients evaluable for response, 22 demonstrated an objective response, including five complete remissions. Therefore, a regimen of 3-h infusion of 250 mg/m2 paclitaxel before CP and FU is tolerable with G-CSF (as above) support in previously untreated patients. The regimen also seems to be highly active against breast and esophageal cancers.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Cisplatino/uso terapêutico , Fluoruracila/uso terapêutico , Neoplasias/tratamento farmacológico , Paclitaxel/uso terapêutico , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Cisplatino/administração & dosagem , Cisplatino/efeitos adversos , Feminino , Fluoruracila/administração & dosagem , Fluoruracila/efeitos adversos , Seguimentos , Humanos , Masculino , Microssomos Hepáticos/metabolismo , Pessoa de Meia-Idade , Neoplasias/metabolismo , Paclitaxel/administração & dosagem , Paclitaxel/efeitos adversos , Paclitaxel/farmacocinética , Seleção de Pacientes , Resultado do Tratamento
5.
Am J Hematol ; 57(4): 326-30, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9544978

RESUMO

A patient with multiple myeloma was noted to have an IgA deficiency during investigation of a possible transfusion reaction due to IgA deficiency and anti-IgA. Because of the patient's age, otherwise good health, and early stage of disease, he was enrolled in a research treatment protocol that involved an allogeneic bone marrow transplant (BMT). The BMT successfully put the patient in complete remission from his multiple myeloma and corrected his IgA deficiency. Class-specific IgG anti-IgA antibody that had been identified prior to BMT was no longer detectable in his plasma. Anaphylactic transfusion reactions were successfully avoided by using a combination of IgA-deficient and washed blood components including the marrow graft, and IgA-reduced intravenous immunoglobulin.


Assuntos
Transplante de Medula Óssea/imunologia , Deficiência de IgA/terapia , Mieloma Múltiplo/terapia , Adulto , Anticorpos Anti-Idiotípicos/metabolismo , Transfusão de Sangue , Humanos , Imunoglobulina A/imunologia , Masculino
6.
J Periodontol ; 68(9): 832-8, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9379326

RESUMO

Proinflammatory cytokines such as tumor necrosis factor-alpha (TNF-alpha) and interleukin 1 beta (IL-1 beta) also possess bone-resorptive properties, and are generally considered to play a role in the pathogenesis of periodontal disease. In the present study, TNF-alpha and IL-1 beta production by oral and peripheral blood polymorphonuclear leukocytes (PMN) was examined in 40 patients with adult periodontitis and 40 orally healthy matched controls. Oral PMN released considerable amounts of both cytokines in unstimulated culture, and there was no difference between patients and controls when the cytokine levels were corrected for cell number. However, when the effect of disease activity was examined, cytokine release by oral PMN was found to be greatest in patients with advanced periodontitis. Within the healthy control group, IL-1 beta production by oral PMN was significantly higher in males (Mann-Whitney test, P = 0.0008). Examination of IL-1 beta production by peripheral blood PMN exposed to recombinant human granulocyte-macrophage colony stimulating factor revealed no difference between the patient and control groups. In contrast, IL-1 beta production by peripheral blood PMN was significantly reduced in patients with advanced disease (Mann-Whitney test, P = 0.02), and peripheral PMN IL-1 beta synthesis was greater in female controls (Mann-Whitney test, P = 0.054). No effect of race on cytokine production could be discerned in patients or controls. These results indicate that several factors influence cytokine production in oral health and disease, and that a dichotomy in cytokine gene expression exists between oral and peripheral blood PMN in adult periodontitis.


Assuntos
Interleucina-1/biossíntese , Mucosa Bucal/imunologia , Neutrófilos/imunologia , Periodontite/imunologia , Fator de Necrose Tumoral alfa/biossíntese , Adulto , População Negra , Reabsorção Óssea/imunologia , Estudos de Casos e Controles , Células Cultivadas , Feminino , Regulação da Expressão Gênica , Fator Estimulador de Colônias de Granulócitos e Macrófagos/farmacologia , Humanos , Interleucina-1/genética , Contagem de Leucócitos , Masculino , Mucosa Bucal/patologia , Neutrófilos/patologia , Periodontite/etiologia , Periodontite/patologia , RNA Mensageiro/análise , RNA Mensageiro/genética , Proteínas Recombinantes , Fatores Sexuais , Fator de Necrose Tumoral alfa/genética , População Branca
8.
Mycopathologia ; 124(1): 47-54, 1993 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8159217

RESUMO

Peripheral blood lymphocytes were isolated from broiler chicks that had ingested feed amended with autoclaved Fusarium proliferatum culture material containing fumonisin B1 (FB1), fumonisin B2 (FB2) and moniliformin. Lymphocyte viability was determined for birds that were placed on amended rations at day 1 or day 7 of age at three different levels of mycotoxins, ranging from 61-546 ppm FB1, 14-94 ppm FB2 and 66-367 ppm moniliformin. Reduction of the tetrazolium salt, MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide], to yield MTT formazan, based on mitochondrial metabolic activity, was used to assess cell viability. Lymphocyte cytotoxic effects were observed in all treatment groups on day 21; chicks that started on amended feed at day 1 of age were affected more than those that started at day 7. Abnormal erythrocytes resembling early stages of erythroblasts were observed in peripheral blood from test chicks. Abnormally shaped red cells (poikilocytes) having a spindle-shape with one or both ends pointed were present. Some red cells appeared to be undergoing mitosis. Both reduced lymphocyte viability and abnormal erythrogenesis occurred in chicks given feed amended with F. proliferatum culture material containing FB1, FB2 and moniliformin.


Assuntos
Galinhas , Ciclobutanos/toxicidade , Eritrócitos/citologia , Fumonisinas , Linfócitos/citologia , Micotoxinas/toxicidade , Ração Animal , Animais , Carcinógenos Ambientais/toxicidade , Sobrevivência Celular , Fusarium/química , Masculino
9.
Skull Base Surg ; 3(2): 91-106, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-17170896

RESUMO

Seventeen patients with petroelival and foramen magnum meningiomas encasing the vertebral or basilar arteries and their branches were surgically excised over a 3-year period. All six cases with vertebral artery encasement were totally excised. One vertebral artery was occluded, one was repaired, and one was replaced with a vein graft. None of the patients had a permanent major neurologic deficit. In one patient with vertebral and basilar artery encasement, a hypoplastic vertebral artery was occluded and the tumor was totally excised. She had a transient worsening of hemiparesis, presumably due to the dissection of tumor from the brainstem. Among the ten patients with encasement of the basilar artery and branches, injury to the basilar artery occurred in two patients, both were repaired. Injuries to one superior cerebellar artery, one anterior inferior cerebellar artery, and one perforating vessel could not be repaired. Three patients sustained major neurologic deficits, but only in two did this result in permanent functional deterioration. Three of the ten patients had a gross total resection, five had subtotal resection (90% or more of tumor volume), and two had resection of 70% of the tumor volume. Eight patients had improvement in their Karnofsky scores. None showed recurrence or regrowth on follow-up ranging from 2 to 6 years. Greater difficulty with dissection was experienced in previously operated patients, and in patients who did not have an arachnoid plane between the brainstem and the tumor. Magnetic resonance imaging was the most useful preoperative test. It is concluded that meningiomas with vertebrobasilar artery encasement can be removed successfully with modern skull base surgery techniques. The surgeon needs to exercise caution and judgment in deciding how far the removal of these lesions should be pursued.

10.
Acta Neurochir Suppl (Wien) ; 53: 171-82, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1803876

RESUMO

The surgical management of intradural clival tumours is difficult due to the relative inaccessibility of the clivus through traditional neurosurgical approaches, and the intimate relationship of such tumours to critical neurovascular and brainstem structures. This report concentrates on the experience with clival meningiomas, which are the most common intradural clival tumours. Between July 1983 and July 1990, 52 patients with petroclival meningiomas underwent surgical excision of their tumours. A variety of skull base approaches were utilized to obtain wide tumour exposure with minimal brain retraction. Large or giant tumours required multiple approaches and staged removal of tumour. Tumour resection was evaluated by a standard protocol of postoperative MR or CT scans. Total tumour resection was achieved in 38 cases (73%), subtotal resection in 11 (21%) and partial resection in 3 (6%). Follow-up has ranged from 4 to 83 months. Two patients had recurrence of tumour requiring re-operation with one receiving additional external beam radiation. Two postoperative deaths occurred, one from pneumonia and another from infectious complications. The most common postoperative morbidity were lower cranial nerve palsy, aspiration peumonia and temporary hemiparesis.


Assuntos
Craniotomia/métodos , Neoplasias Meníngeas/cirurgia , Meningioma/cirurgia , Microcirurgia/métodos , Adulto , Idoso , Fossa Craniana Posterior/cirurgia , Feminino , Seguimentos , Humanos , Imageamento por Ressonância Magnética , Masculino , Neoplasias Meníngeas/patologia , Meningioma/patologia , Pessoa de Meia-Idade , Exame Neurológico , Complicações Pós-Operatórias/diagnóstico , Tomografia Computadorizada por Raios X
11.
Plast Reconstr Surg ; 85(6): 853-8, 1990 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2349291

RESUMO

A modified technique for the surgical correction of trigonocephaly is presented. The technical modifications are designed both to increase the stability of fixation of the supraorbital bar and lateral canthal advancements and to increase interorbital distance and anterior cranial fossa volume when utilized in those patients who exhibit the full expression of trigonocephaly, including midline ridging, bifrontal recession, hypotelorbitism, shortened anterior cranial fossa, deficient projection of lateral orbit, and bitemporal narrowing. It is a modification of the supraorbital bar remodeling/advancement procedure as originally described by Marchac with the introduction of a nasofrontal osteotomy and superior osteotomy bone graft and midline miniplate fixation of the supraorbital bar to the nasofrontal junction. Its use in 20 patients has been favorable.


Assuntos
Craniossinostoses/cirurgia , Crânio/anormalidades , Cirurgia Plástica/métodos , Placas Ósseas , Transplante Ósseo , Pré-Escolar , Humanos , Lactente , Órbita/cirurgia , Osteotomia/métodos , Crânio/cirurgia
12.
J Periodontol ; 57(11): 672-80, 1986 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-3550033

RESUMO

This study evaluated clinically the effectiveness of hand versus sonic subgingival scaling and root planing in the removal of calculus by visually examining the root surface at the time of periodontal flap surgery. Consideration was given to the method of instrumentation, probing depth, number of roots, and type of tooth surface. Eleven patients with moderate to advanced periodontal disease were evaluated. Four subjects were scaled and root planed with the Titan-S only, four with curettes only, and three with the Titan-S + curettes. At reevaluation 3 to 6 weeks after scaling and root planing, the decision to perform periodontal flap surgery was made based upon probing depth, bleeding upon probing, previous access to the root surface, furcation involvement, and the patient's level of oral hygiene. A full thickness mucoperiosteal flap was elevated to gain access to the root surface and measure the distance from the cementoenamel junction to the residual calculus. A total of 690 surfaces were evaluated surgically. The percentage of surfaces with residual calculus for each method of instrumentation was: Titan-S only (31.9%), curettes only (26.8%), and Titan-S + curettes (16.9%). Overall, 15.7% of the surfaces probing 0 to 3 mm, 29.3% of the surfaces probing 4 to 5 mm, and 44.4% of the surfaces probing 6 to 12 mm had residual calculus.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Cálculos Dentários/terapia , Profilaxia Dentária/instrumentação , Raspagem Dentária/instrumentação , Som , Curetagem Subgengival/instrumentação , Raiz Dentária/cirurgia , Cálculos Dentários/patologia , Desenho de Equipamento , Gengivoplastia , Humanos , Bolsa Periodontal/patologia , Distribuição Aleatória , Raiz Dentária/patologia
13.
J Dent Res ; 62(8): 917-21, 1983 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-6345618

RESUMO

Crevicular fluid from gingivitis patients contains significant levels of a cysteine protease which was characterized as the lysosomal protease cathepsin B, as judged by substrate specificity, thiol dependence, pH optimum, kinetic parameters, pH stability, and inhibitor sensitivities. A highly-sensitive fluorometric assay procedure was used to establish the mean level of cathepsin B activity for 25 gingivitis patients.


Assuntos
Catepsinas/análise , Líquido do Sulco Gengival/análise , Gengivite/metabolismo , Catepsina B , Catepsinas/antagonistas & inibidores , Catepsinas/metabolismo , Humanos , Concentração de Íons de Hidrogênio
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