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1.
3 Biotech ; 11(2): 39, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33479594

RESUMO

In the present study, a sequential staining process of polyphenoloxidase and phenoloxidase enzymes was designed by the zymography technique. As a first step, electrophoresis was carried out under native conditions, and later, first staining was carried out with a revealing solution of 3-methyl-2-benzothiazoline hydrazone (MBTH)-3-dimethylamino benzoic acid (DMAB) that allowed the visualization of polyphenoloxidase enzymes, and later and using the same gel, we proceeded to the differential staining of phenoloxidase, adding a solution of H2O2. The technique was standardized using commercial enzymes of laccase (T. versicolor) and horseradish. The technique was used to identify polyphenoloxidases (laccases) and phenoloxidases (lignin peroxidase) of crude extracts obtained from the growth of the basidiomycete Lentinus strigosus on Pinus radiata. The technique showed great sensitivity to detect the different enzymatic activities (1.56 Activity Unit/mL minimum) in the same gel without interference between the enzymes and the solutions used. On the other hand, the efficiency of the technique was compared with the substrates that are commonly used for the detection of this type of activities such as 2,2'-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) and guaiacol, observing greater sensitivity and minimal interference, so that the present method will allow in the same gel, and visualize polyphenoloxidase and phenoloxidase activities simultaneously facilitating expression studies.

2.
Actas Urol Esp (Engl Ed) ; 43(9): 495-502, 2019 Nov.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-31155375

RESUMO

INTRODUCTION AND OBJECTIVES: The objective of this study is to evaluate overall survival (OS), cancer-specific survival (CSS), relapse-free survival, local and distant (LRFS and DRFS, respectively) rates in patients with pT3a renal cell carcinoma (RCC) considering the perirenal and/or sinus fat infiltration (FI) as prognostic factors. MATERIALS AND METHODS: Retrospective cohort of patients with pT3a RCC who underwent radical or partial nephrectomy. The data were extracted from the LARCG (Latin American Renal Cancer Group) database. The demographic, clinical, pathological and surgical variables were evaluated. FI was divided into 4 groups (vein, perirenal, sinus and both fats infiltration). The Kaplan Meier and Cox regression curves were performed. RESULTS: 293 patients were included in the study. The mean age was 61.4 years. The median follow-up was 21 months (r: 1-194). CSS, RFS, LRFS and DRFS estimated at 3 years in the group of both fats' infiltration were 53.1, 45.1, 58.7 and 51.6 months, respectively, and always statistically lower than the rest (P˂0.005). In the multivariate analysis, the infiltration of both fats significantly increased specific mortality, overall and local relapse with respect to vein infiltration (HR: 4.5, 2.42 and 8.08, respectively). The Fuhrman grade and renal pelvis infiltration were independent predictors of CSS and RFS. CONCLUSIONS: Infiltration of both fats increases the risk of overall and local relapse in pT3a RCC. In the same way, it is associated with a lower cancer-specific survival and should be considered as a factor of poor prognosis.


Assuntos
Tecido Adiposo/patologia , Carcinoma de Células Renais/mortalidade , Carcinoma de Células Renais/patologia , Neoplasias Renais/mortalidade , Neoplasias Renais/patologia , Estudos de Coortes , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida
3.
Radiologia (Engl Ed) ; 61(4): 333-336, 2019.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-30772003

RESUMO

Crohn's disease is an autoimmune disease that predominantly affects the gastrointestinal tract. Crohn's disease is diagnosed at a young age and runs a chronic course with acute flare-ups. When patients with Crohn's disease present with flare-ups at the emergency department, they are usually managed in a way similar to patients with acute abdomen; there is no consensus about the most appropriate imaging work-up for patients with flare-ups of Crohn's disease. Thus, we decided to review the literature about the imaging tests indicated (whether related to their diagnostic performance or to lower exposure to ionizing radiation) for acute flare-ups in patients with Crohn's disease.


Assuntos
Abdome Agudo/diagnóstico por imagem , Doença de Crohn/diagnóstico por imagem , Abdome Agudo/etiologia , Doença de Crohn/complicações , Emergências , Humanos
4.
Rev. argent. dermatol ; Rev. argent. dermatol;99(4): 59-66, dic. 2018.
Artigo em Espanhol | LILACS | ID: biblio-985204

RESUMO

RESUMEN: El melanoma es una neoplasia que se origina de los melanocitos, células derivadas de la cresta neural. En el Ecuador, entre el 2001 y 2005 se diagnosticaron en Quito en promedio: 18 casos anuales de melanoma en hombres y 26 casos en mujeres, con una tasa de incidencia de 2.5 y 3.2 respectivamente, mientras queen Guayaquil, durante el período 2003-2006 fueron reportados 49 casos en total, con una incidencia de 0.9 por cada 100.000 habitantes en hombres y 0.1 en mujeres. Siempre que se pueda es preferible una biopsia escisional, extirpando la lesión entera. La determinación del ganglio centinela junto al nivel de Clark, el espesor de Breslow y la ulceración del tumor, son considerados los factores pronósticos más importantes del melanoma maligno.


SUMMARY: Melanoma is a neoplasm that originates from the melanocytes, cells derived from the neural crest. In Ecuador, between 2001 and 2005 an average of 18 cases in men and 26 cases in women were diagnosed in Quito, with an incidence rate of 2.5 and 3.2 respectively, while in Guayaquil, during the period 2003-2006, 49 cases were reported, with an incidence of 0.9 per 100.000 inhabitants in men and 0.1 in women. The exact etiology is not clear, it is considered a heterogeneous diseasewith multifactorial origin. Whenever possible, an excisional biopsy is preferable, removing the entire lesion. The determination of the sentinel lymph node along with the Clark level, the Breslow thickness and the ulceration of the tumor, are considered the most important prognostic factors of malignant melanoma.

5.
Radiologia ; 59(2): 115-127, 2017.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-27979433

RESUMO

Acute pelvic pain is a common condition in emergency. The sources of acute pelvic pain are multifactorial, so it is important to be familiar with this type of pathologies. The purpose of this article is review the main causes of gynecological acute pelvic pain and their radiologic appearances to be able to make an accurate diagnosis and provide objective criteria for patient management.


Assuntos
Dor Aguda/diagnóstico por imagem , Doenças dos Genitais Femininos/diagnóstico por imagem , Dor Pélvica/diagnóstico por imagem , Dor Aguda/etiologia , Diagnóstico Diferencial , Emergências , Endometriose/complicações , Feminino , Doenças dos Genitais Femininos/complicações , Humanos , Cistos Ovarianos/complicações , Doença Inflamatória Pélvica/complicações , Dor Pélvica/etiologia , Gravidez , Gravidez Ectópica , Anormalidade Torcional/complicações
6.
J Mater Chem B ; 3(48): 9233-9241, 2015 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-32262922

RESUMO

Nitric oxide (NO) is a biologically-active free radical involved in numerous physiological processes such as regulation of vasodilation, promotion of cell proliferation and angiogenesis, and modulation of the inflammatory and immune responses. Furthermore, NO has demonstrated the ability to mitigate the foreign body response that often results in the failure of implanted biomedical devices. Although NO has promising therapeutic value, the short physiological half-life of exogenous NO complicates its effective delivery. For this reason, the development of NO-releasing materials that permit the localized delivery of NO is an advantageous method of utilizing this molecule for biomedical applications. Herein, we report the synthesis and characterization of biodegradable NO-releasing polyesters prepared from citric acid, maleic acid, and 1,8-octanediol. NO release was achieved by incorporation of S-nitrosothiol donor groups through conjugation of cysteamine and ethyl cysteinate to the polyesters, followed by S-nitrosation with tert-butyl nitrite. The extent of NO loading and the release properties under physiological conditions (pH 7.4 PBS, 37 °C) were determined by chemiluminesence-based NO detection. The average total NO content of poly(citric-co-maleic acid-co-1,8-octanediol)-cysteamine was determined to be 0.45 ± 0.07 mol NO g-1 polymer, while the NO content for poly(citric-co-maleic acid-co-1,8-octanediol)-ethyl cysteinate was 0.16 ± 0.04 mol NO g-1 polymer. Continuous NO release under physiological conditions was observed for at least 6 days for the cysteamine analog and 4 days for the ethyl cysteinate analog. Cell viability assays and morphological studies with human dermal fibroblasts indicated an absence of toxic leachates at a cytotoxic level, and suggested that these citrate-based polyesters may be suitable for future biomedical applications.

7.
ACS Appl Mater Interfaces ; 6(15): 12307-20, 2014 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-25026120

RESUMO

Herein, we describe the surface modification of an S-nitrosated polymer derivative via H2O plasma treatment, resulting in polymer coatings that maintained their nitric oxide (NO) releasing capabilities, but exhibited dramatic changes in surface wettability. The poly(lactic-co-glycolic acid)-based hydrophobic polymer was nitrosated to achieve a material capable of releasing the therapeutic agent NO. The NO-loaded films were subjected to low-temperature H2O plasma treatments, where the treatment power (20-50 W) and time (1-5 min) were varied. The plasma treated polymer films were superhydrophilic (water droplet spread completely in <100 ms), yet retained 90% of their initial S-nitrosothiol content. Under thermal conditions, NO release profiles were identical to controls. Under buffer soak conditions, the NO release profile was slightly lowered for the plasma-treated materials; however, they still result in physiologically relevant NO fluxes. XPS, SEM-EDS, and ATR-IR characterization suggests the plasma treatment resulted in polymer rearrangement and implantation of hydroxyl and carbonyl functional groups. Plasma treated samples maintained both hydrophilic surface properties and NO release profiles after storage at -18 °C for at least 10 days, demonstrating the surface modification and NO release capabilities are stable over time. The ability to tune polymer surface properties while maintaining bulk properties and NO release properties, and the stability of those properties under refrigerated conditions, represents a unique approach toward creating enhanced therapeutic biopolymers.


Assuntos
Interações Hidrofóbicas e Hidrofílicas , Ácido Láctico/química , Óxido Nítrico/química , Gases em Plasma/química , Ácido Poliglicólico/química , Catálise , Cisteína/química , Hidrólise , Microscopia Eletrônica de Varredura , Nitrosação , Espectroscopia Fotoeletrônica , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , S-Nitrosotióis , Espectrometria por Raios X , Espectrofotometria Infravermelho , Espectrofotometria Ultravioleta , Água/química , Molhabilidade
8.
J Robot Surg ; 7(1): 21-7, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27000888

RESUMO

To evaluate whether robotic-assisted radical prostatectomy (dvRP) provides adequate local control of the disease, incidence of positive surgical margins (PSMs) obtained with dvRP was compared with that of laparoscopic radical prostatectomy (LRP) and with that of open radical retropubic prostatectomy (RRP) performed in a single institution by the same surgeons. We also studied whether neurovascular bundle preservation modified PSM rates. The records were retrospectively reviewed from electronic medical data, and three groups of 100 patients were organized. Group 1 included 100 patients who underwent RRP prior to the incorporation of minimally invasive techniques. Group 2 included the first 100 patients who underwent LRP, and group 3 was made up of the first 100 patients who underwent dvRP. All surgical specimens were analyzed by the same pathologist. We used the technique described by Patel et al. for dvRP. LRP was performed using a five-trocar extraperitoneal approach as previously published by the authors. RRP was performed using retrograde dissection as described by Walsh et al. The final decision of preserving neurovascular bundles was made during surgery. Using D'Amico's risk classification, the dvRP group had a lower percentage of patients with low risk (dvRP versus LRP p = 0.017; dvRP versus RRP p = 0.0108). No statistically significant differences were found within high- and intermediate-risk groups. A higher percentage of patients with pT3 disease was found in the dvRP group compared with the RRP group (p = 0.0408). There were no statistically significant differences regarding PSMs among groups (RRP: 25, LRP: 14, dvRP: 18), although when we compared the total number of PSMs we found that the dvRP group had 18 PSMs versus 21 and 50 PSMs for LRP and RRP, respectively. All three groups had more PSMs located posterolaterally. There was a higher percentage of nerve-sparing procedures in the dvRP group (dvRP: 91 patients, LRP: 47 patients, RRP: 5 patients) (p < 0.0001). No statistically significant differences were found in the PSM rates between the three techniques analyzed. The number of nerve-sparing procedures in the dvRP group was statistically higher. However, this preservation did not modify PSM rates.

9.
Food Sci Technol Int ; 17(4): 293-317, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21917640

RESUMO

In recent years, research on the production of active peptides obtained from milk and their potential functionality has grown, to a great extent. Bioactive peptides have been defined as specific protein fragments that have a positive impact on body functions or conditions, and they may ultimately have an influence on health. Individual proteins of casein or milk-derived products such as cheese and yogurt have been used as a protein source to study the isolation and activity of peptides with several applications. Currently, the milk whey waste obtained in the production of cheese also represents a protein source from which active peptides could be isolated with potential industrial applications. The active properties of milk peptides and the results found with regard to their physiological effects have led to the classification of peptides as belonging to the group of ingredients of protein nature, appropriate for use in functional foods or pharmaceutical formulations. In this study, the main peptides obtained from milk protein and the past research studies about its production and biological activities will be explained. Second, an analysis will be made on the methods to determinate the biological activities, the separation of bioactive peptides and its structure identification. All of these form the base required to obtain synthetic peptides. Finally, we explain the experimental animal and human trials done in the past years. Nevertheless, more research is required on the design and implementation of equipment for the industrial production and separation of peptides. In addition, different authors suggest that more emphasis should therefore be given to preclinical studies, proving that results are consistent and that effects are demonstrated repeatedly by several research human groups.


Assuntos
Leite/metabolismo , Peptídeos/metabolismo , Peptídeos/farmacologia , Animais , Caseínas/metabolismo , Laticínios/análise , Descoberta de Drogas , Indústria de Processamento de Alimentos/economia , Humanos , Proteínas do Leite/metabolismo , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/isolamento & purificação , Fragmentos de Peptídeos/metabolismo , Fragmentos de Peptídeos/farmacologia , Peptídeos/química , Peptídeos/isolamento & purificação , Hidrolisados de Proteína/química , Hidrolisados de Proteína/metabolismo , Hidrolisados de Proteína/farmacologia , Resíduos/análise , Resíduos/economia , Proteínas do Soro do Leite
10.
Rev Esp Anestesiol Reanim ; 57(5): 275-80, 2010 May.
Artigo em Espanhol | MEDLINE | ID: mdl-20527341

RESUMO

BACKGROUND AND OBJECTIVE: The latency times of midfemoral sciatic nerve blocks vary greatly. This study investigated the correlation between the type of motor response to nerve stimulation on the one hand and latency and block efficacy on the other. PATIENTS AND METHODS: We enrolled 215 consecutive patients (184 women) undergoing orthopedic foot surgery. A tourniquet was applied above the malleolus. The puncture location was found by palpating to locate the groove between the vastus lateralis and biceps femoris muscles, at the mid-point of the line between the posterior edge of the greater trochanter muscle and the insertion of the biceps femoris muscle in the popliteal fossa. A solution of equal proportions (1:1) of 1.5% mepivacaine (with bicarbonate 1:10) and 0.75% levobupivacaine was injected at a dose of 0.45 mL x kg(-1) (maximum 40 mL) using a 10-cm needle. Nerve stimulation was applied at 100-300 ms, 02-0.4 mA, and 2 Hz. Latency was classified as response in less than 15 minutes, in 15 to 30 minutes, or later than 30 minutes. RESULTS: The evoked motor response was inversion in 30 patients, flexion or extension in 38, plantar flexion in 101, dorsiflexion in 37, and eversion in 9. Shorter latencies (15 minutes) were observed in all patients with inversion or flexion/extension and in 84 (83%) of the 101 patients with plantar flexion. Mid-range latencies were observed in 13% of those with a plantar flexion response and in 29.7% of those with dorsiflexion. All 9 patients with eversion and 17 (45.9%) of the 37 patients with dorsiflexion had the longest latencies. The surgical block was complete for all patients. CONCLUSIONS: This approach provides an effective block with minimum latency in patients who have a flexion or extension motor response in the foot and/or fingers, inversion, or plantar flexion, which assumes that the injection has reached the common trunk of the sciatic or tibial nerve. However, a longer latency is associated with a peroneal motor response, particularly eversion.


Assuntos
Nervo Femoral/fisiologia , Pé/cirurgia , Bloqueio Nervoso/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Anestésicos Locais/farmacologia , Bupivacaína/análogos & derivados , Bupivacaína/farmacologia , Feminino , Nervo Femoral/anatomia & histologia , Nervo Femoral/efeitos dos fármacos , Pé/anatomia & histologia , Pé/inervação , Humanos , Levobupivacaína , Masculino , Mepivacaína/farmacologia , Pessoa de Meia-Idade , Movimento , Procedimentos Ortopédicos , Estudos Prospectivos , Tempo de Reação/efeitos dos fármacos , Tempo de Reação/fisiologia , Adulto Jovem
11.
Chemosphere ; 72(9): 1347-54, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18511104

RESUMO

Methoprene (isopropyl(2E,4E)-11-methoxy-3,7,11-trimethyl-2,4-dodecadienoate) is an insect growth regulator generally used to control insect populations by preventing insect maturation. So far, the effects of the insecticide on mitochondrial bioenergetics were not investigated. In the present work, liver mitochondria from Wistar rats were isolated and features of mitochondrial physiology were characterized in the presence of methoprene. High concentrations of methoprene, in the range of 40-100 nmol/mg of protein could decrease the transmembrane electric potential (Delta Psi) developed by mitochondria and, at the highest concentration, methoprene prevented complete Delta Psi repolarization after ADP addition. The effect was more evident using succinate than with ascorbate+TMPD as substrate. State 3 respiration was approximately 60% inhibited by 80 nmol of methoprene/mg of protein, while state 4 respiration, within the same range of methoprene concentrations, showed a slight increase, when both glutamate-malate and succinate were used as substrates. Additionally, FCCP-stimulated respiration was inhibited to an extent comparable to the effect on state 3, which suggests an interaction of methoprene with the respiratory chain, more evident with glutamate/malate as substrate. The activity of complex I (NADH-ubiquinone oxidorreductase) and that of the segment comprehending complexes II and III (succinate-cytochrome c reductase) were decreased in the presence of methoprene (approximately 60% and 85% of inhibition, respectively, with 300 nmol of methoprene/mg of protein), while the activities of cytochrome c oxidase and ATPase do not seem to be affected. Furthermore, the action of methoprene on the mitochondrial permeability transition was also studied, showing that the insecticide (in the range of 30-80 nmol mg(-1) of protein) decreases the susceptibility of liver mitochondria to the opening of the transition pore, even in non-energized mitochondria. These results lead to the conclusion that methoprene interference with hepatic mitochondrial function occurs only for high concentrations, which implies that the noxious effects of the insecticide reported for a number of non-target organisms are not fully attributable to mitochondrial effects. Therefore, it seems that mitochondrial activity does not represent the primary target for methoprene toxic action.


Assuntos
Metabolismo Energético , Hormônios Juvenis/toxicidade , Metoprene/toxicidade , Mitocôndrias Hepáticas/efeitos dos fármacos , Mitocôndrias Hepáticas/metabolismo , Adenosina Trifosfatases/metabolismo , Animais , Complexo I de Transporte de Elétrons/metabolismo , Eletrofisiologia , Técnicas In Vitro , Masculino , Potenciais da Membrana/efeitos dos fármacos , Mitocôndrias Hepáticas/enzimologia , Consumo de Oxigênio/efeitos dos fármacos , Permeabilidade/efeitos dos fármacos , Ratos , Ratos Wistar , Succinato Citocromo c Oxirredutase/metabolismo
13.
Rev. argent. urol. (1990) ; 70(1): 14-20, ene.-mar. 2005. ilus, graf
Artigo em Espanhol | LILACS | ID: lil-405282

RESUMO

Introducción: La adrenalectomía laparoscópica se ha convertido en una técnica de referencia. El objetivo de este trabajo es mostrar nuestra experiencia inicial en cirugía adrenal laparoscópica, y analizar los resultados quirúrgicos y postquirúrgicos obtenidos. Material y métodos: De agosto del año 2001 a abril del año 2004 inclusive, realizamos en el Servicio de Urología del H.I.B.A 10 cirugías laparoscópicas por patología suprarrenal, por vía transperitoneal. Para el análisis valoramos: datos generales, tiempo operatorio y de internación, complicaciones, necesidad de transfusión sanguínea, evolución postoperatoria, analgesia, anatomía patológica y tiempo de reinicio a la actividad laboral. Indicamos la cirugía en nódulo suprarrenal funcionante, no funcionante mayores de 3 cm. de diámetro, y no funcionante con aumento de tamaño en controles seriados. No incluímos los casos de sospecha de carcinoma suprarrenal. En todos los casos actuó el mismo equipo quirúrgico. Resultados: Fueron operados 10 pacientes, 5 varones y 5 mujeres. Edad promedio: 51,5 años. Presentación: 9 incidentalomas, y 1 hipertenso resistente a la medicación. Tiempo operatorio promedio, 172'. No hubo conversión. La pérdida estimada de sangre fue de 181 ml. No hubo mortalidad. Morbilidad representada por un caso de hemoperitoneo por sangrado del orificio de uno de los trócares, fue reoperado por vía laparoscópica y evolucionó satisfactoriamente. Analgésico: dosis promedio 160 mg. El tiempo promedio de internación fue de 3 días. El peso promedio de los especímenes anátomo-patológicos fue de 91,5 g, y su tamaño promedio fue de 5 cm. Siete pacientes reiniciaron su actividad laboral a las 3 semanas de la cirugía; 3 a las 4 semanas. Conclusión: En nuestra experiencia inicial el abordaje laparoscópico transperitoneal de la glándula suprarrenal constituyó un acceso reproducible y seguro. Los resultados postoperatorios en términos de dolor, tiempo de internación y recuperación postoperatoria resultaron ser auspiciosamente beneficiosos para los pacientes


Assuntos
Adulto , Pessoa de Meia-Idade , Adrenalectomia , Cirurgia Geral , Cirurgia Geral/métodos , Laparoscópios , Neoplasias
15.
An Otorrinolaringol Ibero Am ; 32(6): 567-76, 2005.
Artigo em Espanhol | MEDLINE | ID: mdl-16475544

RESUMO

The hypoglossal nerve or Twelfth-nerve palsy is a rare damage with different causes: tumors or metastases in skull base, cervicals tumors, schwannoma, dissection or aneurysm carotid arteries, stroke, trauma, idiopathic cause, radiation, infections (mononucleosis) or multiple cranial neuropathy. Tumors were responsible for nearly half of the cases in different studies. We studied a female with hypoglossal nerve acute palsy. We made a differential diagnostic with others causes and a review of the literature.


Assuntos
Doenças do Nervo Hipoglosso/fisiopatologia , Doença Aguda , Adulto , Atrofia/patologia , Feminino , Humanos , Doenças do Nervo Hipoglosso/patologia , Imageamento por Ressonância Magnética
16.
Toxicol In Vitro ; 17(5-6): 623-8, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-14599454

RESUMO

Tamoxifen (TAM), a non-steroid antiestrogen, is the mostly used drug for chemotherapy and chemoprevention of breast cancer. However, the mechanisms by which TAM inhibits cell proliferation in breast cancer are not fully understood. TAM strongly incorporates in biomembranes and a variety of effects have been assigned to biophysical and biochemical interactions with membranes. Therefore, a better understanding of the physicochemical basis of interaction of TAM with biomembranes is essential to elucidate the molecular mechanisms of action. A strain of Bacillus stearothermophilus has been used as a model to clarify the interaction of TAM with the cell membrane. TAM effects on the ultrastructure of membranes of this bacterium were evaluated by electron microscopy. Important ultrastructural alterations were observed in B. stearothermophilus treated with TAM, namely change in the geometry of the membrane profile from asymmetric to symmetric, disaggregation of ribosomes, coagulation of the cytoplasmic matrix, occurrence of mesossomes, appearance of fractures in membranes and the alteration of the ultrastructure of cell wall. These ultrastructural alterations confirm that TAM is a membrane-active drug and that membrane damage may be involved in molecular mechanisms of cell death induced by this drug.


Assuntos
Antagonistas de Estrogênios/toxicidade , Geobacillus stearothermophilus/efeitos dos fármacos , Membranas Intracelulares/efeitos dos fármacos , Tamoxifeno/toxicidade , Relação Dose-Resposta a Droga , Geobacillus stearothermophilus/crescimento & desenvolvimento , Geobacillus stearothermophilus/ultraestrutura , Membranas Intracelulares/ultraestrutura , Microscopia Eletrônica , Organelas/efeitos dos fármacos , Organelas/ultraestrutura
17.
Toxicol In Vitro ; 17(5-6): 629-34, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-14599455

RESUMO

A strain of the thermophilic eubacterium Bacillus stearothermophilus was used as a model system to identify membrane mediated cytotoxic effects of 4-hydroxytamoxifen, following previous studies with tamoxifen. With this experimental approach we attempted to further clarify tamoxifen and 4-hydroxytamoxifen membrane interactions often evoked as responsible for their multiple cellular effects. Bacterial growth and the oxygen consumption rate provided quantitative data of the cytotoxic action of hydroxytamoxifen. The effects of hydroxytamoxifen on the physical properties of bacterial lipid membrane preparations were also evaluated by fluorescence polarization of 1,6-diphenyl-1,3,5-hexatriene. Cultures of B. stearothermophilus grown in a complex medium containing hydroxytamoxifen in the concentration range of 1 to 7 microM exhibited progressively longer lag adapting periods, decreased specific growth rates and lower growth yields, as compared to control cultures. Hydroxytamoxifen also affected the electron redox flow of B. stearothermophilus protoplasts and induced significant perturbation of the structural order of bacterial lipid dispersions. We concluded that the bacterial model provides useful information about the nature and repercussion of membrane physical interactions of this lipophilic drug, on the basis of an easy and economic methodology.


Assuntos
Antineoplásicos Hormonais/toxicidade , Antagonistas de Estrogênios/toxicidade , Geobacillus stearothermophilus/efeitos dos fármacos , Tamoxifeno/análogos & derivados , Tamoxifeno/toxicidade , Antineoplásicos Hormonais/metabolismo , Membrana Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Geobacillus stearothermophilus/crescimento & desenvolvimento , Geobacillus stearothermophilus/metabolismo , Bicamadas Lipídicas/metabolismo , Lipossomos/metabolismo , Fluidez de Membrana/efeitos dos fármacos , Modelos Biológicos , Consumo de Oxigênio/efeitos dos fármacos , Tamoxifeno/metabolismo , Temperatura
18.
Blood Cells Mol Dis ; 30(1): 124-31, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12667995

RESUMO

The cutaneous symptoms in non-immediate reactions to drugs are not always clinically distinguishable from those induced by viruses, especially during the early phase of the reaction. Moreover, viral infections and drug reactions often coexist and identification of the etiological agent is necessary. Discerning the differences in the immunological response between both may help in the diagnosis. The aim of this study was to determine possible differences in the immunological response in non-immediate cutaneous reactions to drugs versus cutaneous viral-induced diseases in children. Two groups of children were evaluated: one with non-immediate drug-induced cutaneous reactions (DICR) and another with virus-induced cutaneous reactions (VICR). A third group of children taking the same drugs as the DICR group and with no cutaneous disease or viral infections was included as controls. The lymphocyte markers CD3, CD4, CD8, CD16, CD19, CLA, CD25, CD69, CD45RO, CD45RA were determined by flow cytometry. IL-2, IL-4, IL-5, IFN-gamma, TNF-alpha and IL-10 mRNA were measured by RT-PCR. Data were compared by non-parametric and chi(2) statistical analysis. In DICR group (n=8) the diagnosis was established by temporal association, improvement after drug withdrawal, patch testing, and in some cases by controlled administration. All patients in the VICR group (n=10) were diagnosed based on a positive viral serology: the presence of IgM antibodies or seroconversion of IgG antibodies. There were significant differences between the three groups in peripheral lymphocytes expressing the skin homing receptor CLA (P < 0.01), the early activation marker CD69 (P < 0.001), and the memory (CD3+CD45RO+) (P < 0.02) and naive (CD3+CD45RA+) (P < 0.03) T cell subsets. Children with DICR showed a TH1 mRNA cytokine pattern whereas those with VICR showed a TH0 pattern. In lymphocyte subpopulations from children, differences in the immunological response between DICR and VICR can be detected in the expressions of the activation marker CD69 and the cutaneous homing receptor CLA, and in cytokine mRNA profiles.


Assuntos
Toxidermias/imunologia , Hipersensibilidade a Drogas/imunologia , Vasculite Leucocitoclástica Cutânea/imunologia , Adolescente , Anticorpos Antivirais/sangue , Carbamazepina/efeitos adversos , Cefuroxima/efeitos adversos , Criança , Pré-Escolar , Toxidermias/sangue , Toxidermias/etiologia , Hipersensibilidade a Drogas/sangue , Hipersensibilidade a Drogas/etiologia , Feminino , Citometria de Fluxo , Herpesvirus Humano 4/imunologia , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Imunofenotipagem/métodos , Lamotrigina , Linfócitos/imunologia , Linfócitos/metabolismo , Masculino , Microscopia de Fluorescência , Parvovirus B19 Humano/imunologia , Fenitoína/efeitos adversos , RNA Mensageiro/sangue , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Simplexvirus/imunologia , Pele/imunologia , Pele/patologia , Fatores de Tempo , Triazinas/efeitos adversos , Vasculite Leucocitoclástica Cutânea/sangue , Vasculite Leucocitoclástica Cutânea/etiologia , Viroses/sangue , Viroses/complicações , Viroses/virologia
19.
Rev Esp Anestesiol Reanim ; 49(2): 105-7, 2002 Feb.
Artigo em Espanhol | MEDLINE | ID: mdl-12025239

RESUMO

A man with a pathologic diaphysial fracture of the middle third of the left humerus underwent emergency surgery for osteosynthesis of the fracture. Preoperative examination revealed that intubation would be difficult due to a history of radical surgery for epidermoid carcinoma of the oropharynx, and local-regional anesthesia was therefore considered. An interscalene approach was contraindicated because of the presence of an ulcerated metastatic cutaneous lesion in the area of puncture; and axillary block was also ruled out given that the fracture made movement painful. However, a satisfactory block and optimal conditions for surgery were achieved through an infraclavicular block using a cephalad multiple injection technique. Among the various levels of brachial plexus blockade, the infraclavicular option is little known and the least utilized, considering that one of its advantages is that the upper limb does not need to be moved for referencing (giving it an advantage over the axillary block) and that it has a lower incidence of pneumothorax (in comparison with a supraclavicular approach). Combined with a multiple injection technique and puncture in a cephalad direction, this solution allowed proximal surgery to be performed on the arm of a patient in whom intubation would have been difficult.


Assuntos
Plexo Braquial , Fixação Intramedular de Fraturas , Fraturas Espontâneas/cirurgia , Fraturas do Úmero/cirurgia , Bloqueio Nervoso/métodos , Amidas/administração & dosagem , Analgésicos Opioides/uso terapêutico , Anestésicos Locais/administração & dosagem , Contraindicações , Fraturas Espontâneas/etiologia , Humanos , Fraturas do Úmero/etiologia , Injeções , Intubação Intratraqueal , Masculino , Pessoa de Meia-Idade , Piperidinas/uso terapêutico , Remifentanil , Ropivacaina
20.
Int Arch Allergy Immunol ; 125(4): 297-306, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11574751

RESUMO

BACKGROUND: Spanish gypsies have traditionally lived as nomads, a reason why few epidemiological studies were done in this ethnic group. However, the high prevalence of asthmatic diseases demonstrated in a population residing in the North of Spain induces us to analyse whether it was due to the influence of genetic loci previously implicated in other population studies as causing the disorders. METHODS: DRB1* and DQB1* HLA class II, TCR-Valpha8.1, FcepsilonRI-beta Rsa I exon 7 and intron 2, TNF-beta (LTalpha-Nco I) and CD14, were tested for association with asthma and atopy by multiple regression analysis, in 5 families comprising 87 individuals. RESULTS: Significant associations were found with DQB1*02 (p = 0.02) and DQB1*0301 (p = 0.008) and elevated levels of total serum IgE. A negative association (p = 0.02) was found between total serum IgE and DRB1*14. FcepsilonRI-beta Rsa I-In2 allele 1 was associated with high levels of total serum IgE (p = 0.04). Levels of Der p 1 IgE antibodies were negatively associated with DRB1*11-DQB1*0301 (p = 0.007), and positively with TCR Valpha-8 allele 1 (p = 0.04) and with FcepsilonRI-beta Rsa I-In2 allele 1 (p = 0.009). CONCLUSIONS: Our results do not show any association between asthma and the genetic loci studied although they do suggest the existence of multiple genetic influences on the allergic response in these families.


Assuntos
Asma/genética , Ácaros/imunologia , Roma (Grupo Étnico)/genética , Adulto , Animais , Feminino , Antígenos HLA-DQ/genética , Cadeias beta de HLA-DQ , Antígenos HLA-DR/genética , Humanos , Imunoglobulina E/sangue , Receptores de Lipopolissacarídeos/análise , Receptores de Lipopolissacarídeos/genética , Linfotoxina-alfa/genética , Masculino , Pessoa de Meia-Idade , Polimorfismo Genético , Receptores de IgE/análise
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