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1.
Clin Exp Immunol ; 202(3): 335-352, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32734627

RESUMEN

The aim of this study was to investigate the pathogenesis of combination ipilimumab and nivolumab-associated colitis (IN-COL) by measuring gut-derived and peripheral blood mononuclear cell (GMNC; PBMC) profiles. We studied GMNC and PBMC from patients with IN-COL, IN-treated with no adverse-events (IN-NAE), ulcerative colitis (UC) and healthy volunteers using flow cytometry. In the gastrointestinal-derived cells we found high levels of activated CD8+ T cells and mucosal-associated invariant T (MAIT) cells in IN-COL, changes that were not evident in IN-NAE or UC. UC, but not IN-C, was associated with a high proportion of regulatory T cells (Treg ). We sought to determine if local tissue responses could be measured in peripheral blood. Peripherally, checkpoint inhibition instigated a rise in activated memory CD4+ and CD8+ T cells, regardless of colitis. Low circulating MAIT cells at baseline was associated with IN-COL patients compared with IN-NAE in one of two cohorts. UC, but not IN-COL, was associated with high levels of circulating plasmablasts. In summary, the alterations in T cell subsets measured in IN-COL-affected tissue, characterized by high levels of activated CD8+ T cells and MAIT cells and a low proportion of Treg , reflected a pathology distinct from UC. These tissue changes differed from the periphery, where T cell activation was a widespread on-treatment effect, and circulating MAIT cell count was low but not reliably predictive of colitis.


Asunto(s)
Linfocitos T CD8-positivos , Colitis , Mucosa Intestinal , Ipilimumab/efectos adversos , Células T Invariantes Asociadas a Mucosa , Nivolumab/efectos adversos , Linfocitos T Reguladores , Adulto , Anciano , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/patología , Colitis/inducido químicamente , Colitis/inmunología , Colitis/patología , Femenino , Citometría de Flujo , Humanos , Mucosa Intestinal/inmunología , Mucosa Intestinal/patología , Ipilimumab/administración & dosificación , Masculino , Persona de Mediana Edad , Células T Invariantes Asociadas a Mucosa/inmunología , Células T Invariantes Asociadas a Mucosa/patología , Nivolumab/administración & dosificación , Linfocitos T Reguladores/inmunología , Linfocitos T Reguladores/patología
3.
Anal Bioanal Chem ; 402(1): 473-87, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22127575

RESUMEN

A suite of three green tea-containing Standard Reference Materials (SRMs) has been issued by the National Institute of Standards and Technology (NIST): SRM 3254 Camellia sinensis (Green Tea) Leaves, SRM 3255 Camellia sinensis (Green Tea) Extract, and SRM 3256 Green Tea-Containing Solid Oral Dosage Form. The materials are characterized for catechins, xanthine alkaloids, theanine, and toxic elements. As many as five methods were used in assigning certified and reference values to the constituents, with measurements carried out at NIST and at collaborating laboratories. The materials are intended for use in the development and validation of new analytical methods, and for use as control materials as a component in the support of claims of metrological traceability.


Asunto(s)
Camellia sinensis/química , Análisis de los Alimentos/normas , Té/química , Análisis de los Alimentos/métodos , Estándares de Referencia
4.
Br J Cancer ; 104(12): 1822-7, 2011 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-21587257

RESUMEN

BACKGROUND: Combined therapy of metronomic cyclophosphamide, methotrexate and high-dose celecoxib targeting angiogenesis was used in a phase II trial. METHODS: Patients with advanced cancer received oral cyclophosphamide 50 mg o.d., celecoxib 400 mg b.d. and methotrexate 2.5 mg b.d. for two consecutive days each week. Response was determined every 8 weeks; toxicity was evaluated according to CTC version 2.0. Plasma markers of inflammation, coagulation and angiogenesis were measured. RESULTS: Sixty-seven of 69 patients were evaluable for response. Twenty-three patients had stable disease (SD) after 8 weeks, but there were no objective responses to therapy. Median time to progression was 57 days. There was a low incidence of toxicities. Among plasma markers, levels of tissue factor were higher in the SD group of patients at baseline, and levels of both angiopoietin-1 and matrix metalloproteinase-9 increased in the progressive disease group only. There were no changes in other plasma markers. CONCLUSION: This metronomic approach has negligible activity in advanced cancer albeit with minimal toxicity. Analysis of plasma markers indicates minimal effects on endothelium in this trial. These data for this particular regimen do not support basic tenets of metronomic chemotherapy, such as the ability to overcome resistant tumours by targeting the endothelium.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Ciclofosfamida/uso terapéutico , Metotrexato/uso terapéutico , Neoplasias/tratamiento farmacológico , Pirazoles/uso terapéutico , Sulfonamidas/uso terapéutico , Adulto , Anciano , Anciano de 80 o más Años , Angiopoyetina 1/sangre , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Celecoxib , Ciclofosfamida/administración & dosificación , Femenino , Humanos , Masculino , Metaloproteinasa 9 de la Matriz/sangre , Metotrexato/administración & dosificación , Persona de Mediana Edad , Neoplasias/sangre , Pirazoles/administración & dosificación , Sulfonamidas/administración & dosificación
6.
Int J Oral Maxillofac Surg ; 47(12): 1519-1522, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29970290

RESUMEN

Regression of metastatic melanoma is very rare and occurs in only 0.23% of cases. Metastasis to the oral cavity is particularly uncommon and accounts for only 1-3% of all oral malignancies. This report presents a case of spontaneous and complete regression of a metastatic melanoma in the mandibular ramus. The patient remains asymptomatic more than 2 years after diagnosis. The patient was followed up regularly. It is recommended that further surveillance imaging be performed in asymptomatic patients following discussion with the surgical and oncological teams. This type of surveillance, together with new systemic treatments, is advocated due to its potential to increase long-term survival even after relapse.


Asunto(s)
Neoplasias Mandibulares/patología , Melanoma/patología , Anciano , Humanos , Biopsia Guiada por Imagen , Masculino , Neoplasias Mandibulares/diagnóstico por imagen , Melanoma/diagnóstico por imagen , Estadificación de Neoplasias , Remisión Espontánea
7.
Crit Rev Oncol Hematol ; 53(3): 241-52, 2005 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15718149

RESUMEN

This review examines the current evidence for the use of temozolomide in the treatment of solid tumours. The possible molecular and clinical advantages of temozolomide are identified and the molecular mechanism of temozolomide resistance is explored. Attempts to maximise efficacy have led to manipulation of both dosage and drug scheduling and the evidence for the various strategies is reviewed. Finally, the potential role of combination therapy is considered.


Asunto(s)
Dacarbazina/análogos & derivados , Neoplasias/tratamiento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Apoptosis/efectos de los fármacos , Reparación del ADN/efectos de los fármacos , Dacarbazina/administración & dosificación , Dacarbazina/farmacocinética , Dacarbazina/farmacología , Esquema de Medicación , Humanos , Temozolomida , Resultado del Tratamiento
8.
Diabetes Care ; 21(5): 810-6, 1998 May.
Artículo en Inglés | MEDLINE | ID: mdl-9589246

RESUMEN

OBJECTIVE: Amylin, a secretory peptide of beta-cells, is the constituent peptide of islet amyloid, which is characteristic of NIDDM, and changes in amylin secretion in response to therapies may influence the rate of production of islet amyloid. The primary objective of this study was to determine whether therapy with sulfonylurea or basal insulin in NIDDM would alter amylin secretion in a way that might affect the formation of islet amyloid. RESEARCH DESIGN AND METHODS: In a randomized crossover design, eight subjects with NIDDM underwent three 8-week periods of therapy with diet alone, sulfonylurea, or exogenous basal insulin, with evaluation of amylin, amylin-like peptide (ALP), and glucose and C-peptide concentrations, both during fasting and after a standard breakfast. Changes in beta-cell function (% beta) were assessed, in the basal state by homeostasis model assessment (HOMA) and in the stimulated state by hyperglycemic clamps. Seven nondiabetic control subjects each underwent a meal profile and hyperglycemic clamp. RESULTS: Both sulfonylurea and insulin therapy reduced basal glucose concentrations compared with diet alone, but neither reduced the increased postprandial glucose increments. Both sulfonylurea and insulin therapy increased basal % beta, assessed by HOMA, but only sulfonylurea increased the second-phase C-peptide responses to the hyperglycemic clamp. Sulfonylurea increased time-averaged mean postprandial amylin and ALP concentrations compared with diet alone (geometric mean [1-SD range] for amylin, 4.9 [2.0-11.8] vs. 3.0 [1.4-6.2] pmol/l, P = 0.003; for ALP, 16.4 [8.5-31.7] vs. 10.1 [4.9-20.8] pmol/l, P = 0.001). Insulin therapy reduced basal ALP concentrations compared with diet alone (2.9 [1.5-5.6] vs. 6.0 [2.6-13.6] pmol/l, P = 0.03), but had no effect on postprandial concentrations of amylin (3.0 [1.3-6.5] pmol/l) or ALP (10.0 [5.5-18.1] pmol/l). CONCLUSIONS: By increasing postprandial concentrations of the constituent peptides of islet amyloid, sulfonylurea therapy might increase the rate of deposition of islet amyloid and thereby accelerate the decline of % beta in NIDDM, compared with diet therapy alone.


Asunto(s)
Amiloide/efectos de los fármacos , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Hipoglucemiantes/uso terapéutico , Insulina/uso terapéutico , Islotes Pancreáticos/efectos de los fármacos , Islotes Pancreáticos/fisiopatología , Compuestos de Sulfonilurea/uso terapéutico , Anciano , Amiloide/sangre , Glucemia/efectos de los fármacos , Glucemia/metabolismo , Péptido C/sangre , Péptido C/efectos de los fármacos , Estudios Cruzados , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/fisiopatología , Ayuno , Femenino , Glucosa/metabolismo , Técnica de Clampeo de la Glucosa , Hemoglobina Glucada/efectos de los fármacos , Hemoglobina Glucada/metabolismo , Humanos , Polipéptido Amiloide de los Islotes Pancreáticos , Masculino , Persona de Mediana Edad
9.
FEBS Lett ; 317(1-2): 101-4, 1993 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-8381361

RESUMEN

The hydrogenase of the pathogenic protozoan Trichomonas vaginalis was extracted and partially purified. The catalytic and spectroscopic properties of the enzyme indicate that it belongs to the class of [Fe]-hydrogenases, rather than the [NiFe]-hydrogenases. The hydrogenase activity was highly sensitive to carbon monoxide, 50% inhibition being attained by 1 microM CO. The EPR spectrum of the most active fractions from chromatography, after reduction by hydrogen and partial reoxidation under argon, showed an EPR spectrum at g = 2.10, 2.04, 2.00. This unusual spectrum is characteristic of the 'H-cluster', as seen in [Fe]-hydrogenases of anaerobic bacteria such as Clostridium spp.


Asunto(s)
Hidrogenasas/aislamiento & purificación , Trichomonas vaginalis/enzimología , Animales , Monóxido de Carbono/farmacología , Espectroscopía de Resonancia por Spin del Electrón , Hidrogenasas/antagonistas & inhibidores , Hidrogenasas/química , Hierro/química
10.
Placenta ; 13(5): 429-37, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1470604

RESUMEN

In this study, using gel electrophoresis and Western blotting, we have demonstrated that the content of irPGHS in ovine placenta increases during late gestation prior to the onset of labour. This increase in PGHS tissue content may contribute to the corresponding increased production of prostaglandins by the ovine placenta during this period of pregnancy. Although the mechanism by which PGHS tissue content is elevated at this time remains to be established, one possibility which is currently being investigated in our laboratory is that increased PGHS content reflects an increased level of PGHS gene expression.


Asunto(s)
Placenta/enzimología , Prostaglandina-Endoperóxido Sintasas/análisis , Animales , Western Blotting , Electroforesis en Gel de Poliacrilamida , Femenino , Edad Gestacional , Microsomas/enzimología , Embarazo , Ovinos
11.
Am J Occup Ther ; 42(4): 227-30, 1988 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-3369532

RESUMEN

To investigate the current status of sex education in occupational therapy curricula, a questionnaire survey was mailed to department chairs of 67 university programs that were either accredited or in the application process. A total of 50 programs returned usable responses. The results indicate that occupational therapy may be in a transition period: A significant minority of the respondents were either undecided about or against including sexual functioning in occupational therapy, but the majority were of the opinion that the patient's sexual functioning is an important domain of occupational therapy practice. A high percentage of programs reported that instructional time was being devoted to the basics of sexual functioning, but programs varied considerably in the amount of time allocated for this topic.


Asunto(s)
Terapia Ocupacional/educación , Educación Sexual , Actitud , Curriculum , Estados Unidos
12.
J R Army Med Corps ; 137(1): 50-1, 1991 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-2023171

RESUMEN

Since Atkinson first described idiopathic rupture of a normal spleen in 1874, there has been controversy regarding the application of the terms "idiopathic" and "spontaneous". One such case is reported, and the validity of the description "idiopathic" or "spontaneous" discussed.


Asunto(s)
Rotura del Bazo/diagnóstico , Adulto , Humanos , Masculino , Tamaño de los Órganos , Rotura Espontánea , Rotura del Bazo/patología
13.
J R Army Med Corps ; 133(3): 166-8, 1987 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-3681841

RESUMEN

We report an unusual presentation of angiomyolipoma of the kidney. Whilst a conservative surgical approach is ideal, the greatly increased cardiac output in pregnancy makes haemorrhage more severe and hence more radical surgery is often required. The difficulty in reaching a correct pre-operative diagnosis can lead to an unusual approach to nephrectomy, of which the surgeon should be forewarned.


Asunto(s)
Hemangioma/patología , Neoplasias Renales/patología , Lipoma/patología , Trastornos Puerperales/patología , Choque/patología , Adulto , Femenino , Humanos , Riñón/patología , Embarazo , Rotura Espontánea
14.
J R Army Med Corps ; 132(2): 71-5, 1986 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-3735191

RESUMEN

The purpose of this study was to assess the clinical and pathological value of reports resulting from review of all completed surgical pathology cases submitted to the Army Histopathology Registry (AHR). All histopathological cases completed in the British Army are sent to the AHR for archiving; prior to placing cases in the archive both microscopic material and submitted reports are reviewed by staff of the AHR. A "nonagreed" report is produced for those cases in which the reviewing pathologist has a dissenting opinion or for which he thinks other comments may be helpful. All nonagreed reports produced over a 19 month period were subjected to a further pathological and clinical review. The original surgical pathology reports were compared with AHR reports and the significance of the differences in diagnosis assessed. During the study interval, 4.0% of total cases reviewed were identified as nonagreed record cases. The clinical and pathological reviews placed the nonagreed cases into significant categories in 2.1% and 1.9% of instances respectively. These findings suggest that nonselected review of completed surgical pathology cases identifies a significant proportion of cases for which dissenting opinions may have important clinical and pathological consequences.


Asunto(s)
Hospitales Militares , Hospitales Públicos , Patología Quirúrgica , Garantía de la Calidad de Atención de Salud , Humanos , Londres , Estudios Retrospectivos
15.
Case Rep Oncol ; 7(1): 132-8, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24707261

RESUMEN

We report the case of a 60-year-old woman with metastatic high-grade uterine leiomyosarcoma who achieved a delayed response to second-line therapy with the marine-derived drug trabectedin (Yondelis(®), PharmaMar). We used 2-deoxy-2-[(18)F] fluorodeoxyglucose (FDG)-positron emission tomography (PET-CT) imaging as a tool for response monitoring in parallel with conventional re-staging according to Response Evaluation Criteria in Solid Tumours (RECIST) using computed tomography (CT). We illustrate the role of serial (18)FDG-PET-CT imaging in the functional assessment of tumour response. Three cycles after commencement of trabectedin treatment, a reduction of the maximum standardized uptake value (SUVmax) of the solid component of the pelvic mass was observed, indicating a cystic or necrotic response in the tumour to trabectedin. After 7 cycles of treatment, on (18)FDG-PET-CT there was clear evidence of ongoing disease improvement: the solid pelvic components were at worst stable, with an unchanged SUVmax, and possibly marginally reduced in size, while the pulmonary metastases had further reduced in size and become FDG negative; the bony metastases were stable. After a total of 13 cycles of treatment, administered over 13 months, the patient showed signs of progression on an (18)FDG-PET-CT scan. The safety profile of trabectedin remained manageable, showing no evidence of cumulative toxicity and being associated with a preserved quality of life. This report illustrates potential limitations of RECIST in response assessments and the critical role of serial (18)FDG-PET-CT imaging in assessing response to trabectedin treatment. Therefore, we propose that (18)FDG-PET-CT may improve the assessment of response to trabectedin in selected patients.

18.
J R Coll Surg Edinb ; 39(5): 284-8, 1994 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-7861335

RESUMEN

Kaltostat swabs were implanted subcutaneously in rats to evaluate their biodegradability and ability to evoke local tissue reactions. Implant sites were evaluated after 24 h and after 7 days, 28 days and 12 weeks. Histological sections showed no noticeable degradation of the Kaltostat within the 3 month observation period, contrary to some published reports. Following subsidence of a modest foreign body reaction, implants became embedded in thin fibrous sheaths which were infiltrated with vascular channels and fibroblasts. This study demonstrates that Kaltostat fibres are well tolerated following subcutaneous implantation in the rat model and present no obvious toxic risk or contraindication to their use as wound dressings or as haemostatic agents in general surgery.


Asunto(s)
Alginatos/toxicidad , Hemostáticos/toxicidad , Alginatos/administración & dosificación , Alginatos/farmacocinética , Animales , Biodegradación Ambiental , Implantes de Medicamentos , Femenino , Reacción a Cuerpo Extraño , Ácido Glucurónico , Hemostáticos/administración & dosificación , Hemostáticos/farmacocinética , Ácidos Hexurónicos , Inyecciones Subcutáneas , Masculino , Ratas , Ratas Wistar , Piel/patología
19.
J Gen Microbiol ; 136(10): 2077-87, 1990 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-2176669

RESUMEN

Certain reagents, such as ascorbate or iron salts and thiols, enhance the bacteriostatic action of nitrite on food-spoilage bacteria. This may be due to the formation of nitric oxide and iron-thiol-nitrosyl [( Fe-S-NO]) complexes. The minimum concentrations of these reagents required to inhibit growth of Clostridium sporogenes were investigated. A mixture of nitrite (0.72 mM) with iron (1.44 mM) and cysteine (2.16 mM) was found to be extremely inhibitory when autoclaved and diluted into the culture medium. This mixture caused rapid cessation of growth and loss of cell viability at a final concentration corresponding to 40 microM-nitrite. If added to the initial culture medium, it prevented growth at 5 microM-nitrite. The mixture was more inhibitory, on the basis of the nitrite concentration used, than the 'Perigo factor', obtained by autoclaving nitrite in growth medium. [Fe-S-NO] compounds of known chemical structure were tested to determine if they were responsible for this effect. Total inhibition of cell growth was observed with the tetranuclear clusters [Fe4S3(NO)7] (Roussin's black salt), [Fe4S4(NO)4] or [Fe4Se3(NO)7], added at concentrations equivalent to 10 microM-nitrite, or with [Fe2(SMe)2(NO)4] (methyl ester of Roussin's red salt), equivalent to 200 microM-nitrite. The rate of hydrogen production in growing cell cultures was inhibited by [Fe4S3(NO)7] at levels equivalent to 2.5 microM-nitrite. EPR spectra of the inhibited cells showed features with g-values of 2.03, characteristic of mononuclear iron-nitrosyl species, and, under non-reducing conditions, an unusual signal at g = 1.65. There was no correlation between growth inhibition and the g = 2.03 signal, though there was a better correlation between inhibition and the g = 1.65 signal. The direct effects of the compounds were tested on the iron-sulphur proteins of the phosphoroclastic system, namely ferredoxin, pyruvate-ferredoxin oxidoreductase and hydrogenase. EPR spectra and enzyme assays showed that these proteins were not destroyed by [Fe4S3(NO)7], [Fe4S4(NO)4], [Fe2(SMe)2(NO)4], [Fe(SPh)2(NO)2], or M2 (an autoclaved mixture of 66 mM-cysteine, 3.6 mM-FeSO4 and 0.72 mM-NaNO2) at concentrations higher than those that caused total inhibition of cell growth. Inhibition of cells by [Fe-S-NO] compounds is unlikely to be due to interaction with the preformed enzymes. The possible formation of iron-nitrosyl complexes in vivo, and their inhibitory actions, are discussed.


Asunto(s)
Clostridium/efectos de los fármacos , Cisteína/farmacología , Hierro/farmacología , Nitritos/farmacología , División Celular/efectos de los fármacos , Clostridium/citología , Clostridium/metabolismo , Espectroscopía de Resonancia por Spin del Electrón , Microbiología de Alimentos , Conservantes de Alimentos/farmacología , Hidrogenasas/antagonistas & inhibidores , Proteínas Hierro-Azufre/metabolismo , Cetona Oxidorreductasas/antagonistas & inhibidores , Piruvato-Sintasa
20.
Curr Genet ; 19(5): 343-51, 1991 May.
Artículo en Inglés | MEDLINE | ID: mdl-1833077

RESUMEN

This study details the characteristics of two temperature-conditional pet mutants of yeast, strains ts1860 and ts379, which at the non-permissive temperature show deficiencies in the formation of three mitochondrially encoded subunits of the ATP synthase complex. By analysis of mitochondrial translation products, and of mitochondrial transcription in temperature shift experiments from the permissive (22 degrees C) to the non-permissive (36 degrees C) temperature, it was concluded that the nuclear mutations in both mutants primarily inhibit synthesis of ATP synthase subunit 9, and that reductions in subunit 8 and 6 synthesis are secondary pleiotropic effects. Following transfer to 36 degrees C, cells of mutant ts379 display a near complete inhibition of subunit 9 synthesis within 1 h, coincident with a marked reduction in the level of the cognate oli1 mRNA. On the other hand, near complete inhibition of subunit 9 synthesis in strain ts1860 occurs after 3 h at 36 degrees C, at which time there is little change in the level of subunit 9 mRNA. In both mutants the mRNA levels for subunits 6 and 8 are not significantly affected at the time of inhibition of subunit 9 synthesis. Provision of an alternative source of subunit 8, translated extra-mitochondrially for import into the organelle, does not overcome the mutant phenotype of either mutant at 36 degrees C, confirming that subunit 8 is not the sole or primary deficiency in each mutant. The mutants indicate that the products of a least two nuclear genes (designated AEP1 and AEP2) are required for the expression of the mitochondrial oli1 gene and the synthesis of subunit 9. (ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Núcleo Celular/metabolismo , Regulación Fúngica de la Expresión Génica , Genes Fúngicos , Mitocondrias/metabolismo , Mutación , Saccharomyces cerevisiae/genética , Electroforesis en Gel de Poliacrilamida , Biosíntesis de Proteínas , ATPasas de Translocación de Protón/antagonistas & inhibidores , ATPasas de Translocación de Protón/biosíntesis , ARN de Hongos/genética , ARN Mensajero/genética , Transcripción Genética
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