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1.
Mar Pollut Bull ; 194(Pt B): 115388, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37595454

RESUMO

The influence of the phytoplankton community in the light absorption budget was quantified in coastal waters of the North region of the San Jorge Gulf (Argentinian Patagonia). The phytoplanktonic composition and their absorption spectra were determined. Nanoflagellates and diatoms were the dominant groups. The toxigenic dinoflagellate Dinophysis acuminata was recorded in all the sampling sites. The optical characterization of the particulate material showed that 60 % of the absorption at 443 nm and 88 % of absorption at 675 nm was due to phytoplankton. The contributions of phytoplankton to total absorption at 443 nm wavelengths reached 50 %. The absorption by chromophoric dissolved organic matter (CDOM) and non-algal particles (NAP) was predominant in turbulent waters (>60 %). This study shows the influence of submesoscale physical-biological interactions in the light absorption budget. The field absorption spectra of active optical components are of interest in the assessment and development of regional ocean color satellite algorithms.


Assuntos
Diatomáceas , Dinoflagellida , Fitoplâncton , Algoritmos , Matéria Orgânica Dissolvida
2.
J Phys Condens Matter ; 35(26)2023 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-36972607

RESUMO

Periodic superlattices constitute ideal structures to modulate the transport properties of two-dimensional materials. In this paper, we show that the tunneling magnetoresistance (TMR) in phosphorene can be tuned effectively through periodic magnetic modulation. Deltaic magnetic barriers are arranged periodically along the phosphorene armchair direction in parallel (PM) and anti-parallel magnetization (AM) fashion. The theoretical treatment is based on a low-energy effective Hamiltonian, the transfer matrix method and the Landauer-Büttiker formalism. We find that the periodic modulation gives rise to oscillating transport characteristics for both PM and AM configurations. More importantly, by adjusting the electrostatic potential appropriately we find Fermi energy regions for which the AM conductance is reduced significantly while the PM conductance keeps considerable values, resulting in an effective TMR that increases with the magnetic field strength. These findings could be useful in the design of magnetoresistive devices based on magnetic phosphorene superlattices.

4.
Annu Int Conf IEEE Eng Med Biol Soc ; 2021: 4596-4599, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34892239

RESUMO

During surgical training, it is important for the surgeon develops good motor skills throughout his training. For this reason, various surgical training systems have been developed to enhance these skills. However, one of the great challenges in these training systems is being able to objectively measure the ability and performance of the main surgical tasks, where currently only a global measurement is obtained once the task is completed. In this work, a temporal evaluation scheme is proposed, that is, an evaluation of local surgical performance at different time intervals during the training of typical tasks (knot-tying, needle-passing and suturing). The goal is to automatically classify expert (experience >100 hrs) and non-expert (experience <10 hrs) surgeons according to their performance during training, based on three classifiers: K-Nearest Neighborhood, Random Forest, and Support Vector Machine Unlike other previously reported methods, this work proposes a new evaluation scheme based on segments or time intervals, which can be an indicator of the surgeon's local performance during a robotic surgical task, without the need for direct labeling of the data at the segment level. The classification performance from obtained results was in accuracy 83% to 100%, 88% to 100% of AUC-ROC, and 88% to 100% of F1-Score in the final test between experts and non-experts surgeons, where the Support Vector Machine classifier presented the best performance. These results suggest that this proposed method by time intervals could be used in various surgical trainers to evaluate the local performance of a surgeon during trainingand thus be able to provide a tool for the quantitative visualization of opportunities to improve surgical skills.Clinical relevance- We consider that the proposed method to carry out a local performance evaluation during surgical training can provide useful information in the learning and improvement of surgical skills.


Assuntos
Procedimentos Cirúrgicos Robóticos , Cirurgiões , Competência Clínica , Humanos , Aprendizado de Máquina , Suturas
6.
Sci Adv ; 5(1): eaav1851, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30746475

RESUMO

One of the bottlenecks in realizing the potential of atom-thick graphene membrane for gas sieving is the difficulty in incorporating nanopores in an otherwise impermeable graphene lattice, with an angstrom precision at a high-enough pore density. We realize this design by developing a synergistic, partially decoupled defect nucleation and pore expansion strategy using O2 plasma and O3 treatment. A high density (ca. 2.1 × 1012 cm-2) of H2-sieving pores was achieved while limiting the percentage of CH4-permeating pores to 13 to 22 parts per million. As a result, a record-high gas mixture separation performance was achieved (H2 permeance, 1340 to 6045 gas permeation units; H2/CH4 separation factor, 15.6 to 25.1; H2/C3H8 separation factor, 38.0 to 57.8). This highly scalable pore etching strategy will accelerate the development of single-layer graphene-based energy-efficient membranes.

7.
Allergol Immunopathol (Madr) ; 46(2): 149-154, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29223706

RESUMO

BACKGROUND: Cow's milk protein allergy (CMPA) affects between 0.6 and 0.9% of the general population, and its treatment implies the total elimination of the intake of this protein. Camel's milk has been suggested as an alternative for patients over one year of age who suffer from CMPA due to the difference in the amino acid sequence from that of cow's milk. The objective of this study was to evaluate the safety and tolerability of camel's milk in children with CMPA. METHODS: Crossed clinical trial for the use of camel's milk vs. amino acid formula, carried out at the Dr. Federico Gómez Children's Hospital of Mexico (HIMFG) on patients between one and 18 years of age with diagnosed CMPA confirmed through double-blind, placebo-controlled food challenges (DBPCFCs). Only those whose allergies were confirmed were randomly placed into two groups: those to be administered camel's milk and those to be administered the amino-acid formula for two weeks, followed by a six-week wash-out period, and then a group crossing for a further two weeks. RESULTS: 49 patients with suspected CMPA were included in the study; the diagnosis was confirmed through DBPCFCs in 15 patients, who were those who participated in the study. After having been administered camel's milk, none of the patients presented adverse effects. CONCLUSIONS AND CLINICAL RELEVANCE: Camel's milk is safe and tolerable in patients above one year of age with CMPA and can be considered as a good alternative given the benefit of its taste compared to other formulas.


Assuntos
Alérgenos/imunologia , Hipersensibilidade a Leite/imunologia , Proteínas do Leite/imunologia , Adolescente , Animais , Camelus , Bovinos , Criança , Pré-Escolar , Reações Cruzadas , Estudos Cross-Over , Dietoterapia , Ingestão de Alimentos , Feminino , Humanos , Lactente , Masculino , Hipersensibilidade a Leite/tratamento farmacológico
8.
Rev. biol. trop ; 65(1): 1-8, Jan.-Mar. 2017. tab, ilus
Artigo em Inglês | LILACS | ID: biblio-897520

RESUMO

AbstractThe gordiids are freshwater representatives of the parasite phylum Nematomorpha that function as a link between aquatic and terrestrial ecosystems. In recent years, different ecotoxicologic studies have been made with the South-American gordiid species, Chordodes nobilii, that have demonstrated the capacity of this group to act as a bioindicator of contamination. Despite the Gordiida's ecologic relevance, further studies are still needed to elucidate different aspects of the biology of the class, and among those, the infective capacity, a parameter that can be evaluated by the infection index mean abundance (IIMA). A knowledge of the intrinsic variability in the infective capacity of C. nobilii would warrant priority in order to establish, the range of acceptable responses for normal or standard conditions in the laboratory, and, to compare the criteria among different assays. The objective of this study was to establish a baseline value for the infective capacity for C. nobilii larvae, under controlled laboratory conditions, by employing the IIMA as the evaluation parameter. To that end, we analyzed the infective capacity of C. nobilii larvae that had hatched from different strings of eggs laid in the laboratory by a total of 12 females. The C. nobilii adults were collected from streams within the Argentina Sauce Grande basin, between 2006 and 2009. Once in the laboratory, after mating, the females were placed in individual containers for oviposition. The egg strings obtained from each female were cut in 3 mm long segments; and when free larvae were observed, the segments (N= 90) were placed together with 30 Aedes aegypti larvae for evaluation of the gordiids' infective capacity. After 72 h, the mosquito larvae were observed by microscopy in order to quantify the C. nobilii larvae in body cavities. The IIMAs were calculated as the total number of C. nobilii larvae present divided by total number of A. aegypti larvae examined. For analysis of the IIMAs obtained, the data were grouped according to the female who made the original ovoposition. Our results enabled the corroboration of an ample range of responses in the infective capacity of this species, a characteristic that would normally be linked to the progenitors originating the hatch. Because this relationship prevents the establishment of a baseline for making comparisons among assays with gordiids, through the IIMA as a response parameter, we recommend expressing the IIMA values in each assay relative to their respective controls. These findings also provide evidence for the greater success in infections by certain members of the progeny over others. Finally, on the basis of the results obtained from this study, we stress the relevance of the use of the IIMA as a decisive aspect to be considered in different studies on the biology of Gordiida. Rev. Biol. Trop. 65 (1): 1-8. Epub 2017 March 01.


ResumenLos gordiidos son representantes dulceacuícolas del Phylum parásito Nematomorpha que actúan como un enlace entre ecosistemas acuáticos y terrestres. En años recientes, diferentes estudios ecotoxicológicos se han desarrollado con una especie sudamericana de gordiido, C. nobilii, que ha demostrado la capacidad de este grupo de actuar como bioindicador de contaminación. A pesar de su evidente importancia ecológica, aún se necesitan realizar estudios para dilucidar distintos aspectos de su biología, entre estos, la capacidad infectiva, un parámetro que puede evaluarse utilizando el Índice de Infección Abundancia Media (IIMA). El conocimiento de la variabilidad intrínseca en la capacidad infectiva de C. nobilii merece prioridad con el objeto de establecer el ámbito de respuesta aceptable para condiciones normales o estándar en el laboratorio, y que permita comparar los resultados entre distintos ensayos. El objetivo de este estudio es establecer la línea de base de la capacidad infectiva del gordiido C. nobilii en condiciones controladas de laboratorio, empleando el IIMA como parámetro de evaluación. Con este fin, se analizó la capacidad infectiva de larvas de C. nobilii que eclosionaron de diferentes cordones de huevos depositados por un total de 12 hembras, mantenidas en laboratorio. Los adultos de C. nobilii fueron recolectados de arroyos de la cuenca argentina Sauce Grande, entre 2006 y 2009. Una vez en el laboratorio, después de la cópula, las hembras se ubicaron en recipientes individuales a la espera de la oviposición. Los cordones de huevos obtenidos de cada hembra se cortaron en segmentos de 3 mm de longitud; y cuando las larvas libres fueron observadas al microscopio, los segmentos (N= 90) fueron ubicados junto con 30 larvas de Aedes aegypti para evaluar la capacidad infectiva del gordiido. Después de 72 h, las larvas del mosquito fueron observadas al microscopio para contabilizar las larvas de C. nobilii en las cavidades corporales. El IIMA fue calculado como el número total de larvas de C. nobilii presentes dividido entre el número total de larvas de A. aegypti examinadas. Para el análisis de los IIMAs obtenidos, los datos fueron agrupados de acuerdo a la hembra que hizo la oviposición. Nuestros resultados permiten corroborar un amplio rango de respuesta en la capacidad infectiva de esta especie, que estaría vinculada al origen de la camada. Debido a que no se pudo establecer una línea de base para realizar comparaciones entre estudios en los gordiidos utilizando el IIMA como parámetro de respuesta, se aconseja relativizar los valores de los IIMAs a sus respectivos controles. Estos resultados también pusieron en evidencia la ventaja en el éxito de infección de algunas progenies sobre las restantes. Finalmente, con base en los resultados obtenidos a partir de este estudio se plantea la importancia del uso del IIMA como punto final a considerar en distintos estudios sobre la biología de los gordiida.


Assuntos
Animais , Carga Parasitária/métodos , Helmintos/patogenicidade , Larva/patogenicidade , Oviposição/fisiologia , Padrões de Referência , Fatores Sexuais , Estatísticas não Paramétricas , Aedes/parasitologia , Água Doce/parasitologia
9.
Rev Biol Trop ; 65(1): 1-8, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29465953

RESUMO

The gordiids are freshwater representatives of the parasite phylum Nematomorpha that function as a link between aquatic and terrestrial ecosystems. In recent years, different ecotoxicologic studies have been made with the South-American gordiid species, Chordodes nobilii, that have demonstrated the capacity of this group to act as a bioindicator of contamination. Despite the Gordiida's ecologic relevance, further studies are still needed to elucidate different aspects of the biology of the class, and among those, the infective capacity, a parameter that can be evaluated by the infection index mean abundance (IIMA). A knowledge of the intrinsic variability in the infective capacity of C. nobilii would warrant priority in order to establish, the range of acceptable responses for normal or standard conditions in the laboratory, and, to compare the criteria among different assays. The objective of this study was to establish a baseline value for the infective capacity for C. nobilii larvae, under controlled laboratory conditions, by employing the IIMA as the evaluation parameter. To that end, we analyzed the infective capacity of C. nobilii larvae that had hatched from different strings of eggs laid in the laboratory by a total of 12 females. The C. nobilii adults were collected from streams within the Argentina Sauce Grande basin, between 2006 and 2009. Once in the laboratory, after mating, the females were placed in individual containers for oviposition. The egg strings obtained from each female were cut in 3 mm long segments; and when free larvae were observed, the segments (N= 90) were placed together with 30 Aedes aegypti larvae for evaluation of the gordiids' infective capacity. After 72 h, the mosquito larvae were observed by microscopy in order to quantify the C. nobilii larvae in body cavities. The IIMAs were calculated as the total number of C. nobilii larvae present divided by total number of A. aegypti larvae examined. For analysis of the IIMAs obtained, the data were grouped according to the female who made the original ovoposition. Our results enabled the corroboration of an ample range of responses in the infective capacity of this species, a characteristic that would normally be linked to the progenitors originating the hatch. Because this relationship prevents the establishment of a baseline for making comparisons among assays with gordiids, through the IIMA as a response parameter, we recommend expressing the IIMA values in each assay relative to their respective controls. These findings also provide evidence for the greater success in infections by certain members of the progeny over others. Finally, on the basis of the results obtained from this study, we stress the relevance of the use of the IIMA as a decisive aspect to be considered in different studies on the biology of Gordiida.


Assuntos
Helmintos/patogenicidade , Larva/patogenicidade , Carga Parasitária/métodos , Aedes/parasitologia , Animais , Água Doce/parasitologia , Oviposição/fisiologia , Padrões de Referência , Fatores Sexuais , Estatísticas não Paramétricas
10.
Arch. Soc. Esp. Oftalmol ; 90(7): 327-330, jul. 2015. ilus
Artigo em Espanhol | IBECS | ID: ibc-138253

RESUMO

CASO CLÍNICO: Mujer de 73 años en tratamiento con escitalopram que presentó glaucoma agudo de ángulo cerrado secundario a efusión uveal tras duplicar la dosis de dicho fármaco 3 días antes. Evolucionó favorablemente tras la suspensión del antidepresivo además de tratamiento hipotensor tópico y prednisona vía oral. DISCUSIÓN: La efusión uveal secundaria a fármacos es un síndrome infrecuente. Se puede acompañar de miopización y glaucoma agudo por cierre angular. El diagnóstico correcto y la suspensión del fármaco conducen a la resolución de esta nosología


CASE REPORT: A 73 year-old woman with depression treated with escitalopram developed acute secondary angle closure glaucoma related to uveal effusion after duplicating the drug dose 3 days before. She evolved favorably once the antidepressant treatment was suspended and a new treatment with topical hypotensive therapy and oral prednisone was used. DISCUSSION: The uveal effusion syndrome associated to medicines is rare; it may be associated with acute myopic shift and acute angle closure glaucoma. The correct diagnosis and discontinuation of the drug lead to the resolution of this nosology


Assuntos
Adulto , Feminino , Humanos , Doenças da Úvea/induzido quimicamente , Antidepressivos/efeitos adversos , Miopia/induzido quimicamente , Glaucoma/induzido quimicamente , Cefaleia/etiologia
11.
Arch Soc Esp Oftalmol ; 90(7): 327-30, 2015 Jul.
Artigo em Espanhol | MEDLINE | ID: mdl-25817959

RESUMO

CASE REPORT: A 73 year-old woman with depression treated with escitalopram developed acute secondary angle closure glaucoma related to uveal effusion after duplicating the drug dose 3 days before. She evolved favorably once the antidepressant treatment was suspended and a new treatment with topical hypotensive therapy and oral prednisone was used. DISCUSSION: The uveal effusion syndrome associated to medicines is rare; it may be associated with acute myopic shift and acute angle closure glaucoma. The correct diagnosis and discontinuation of the drug lead to the resolution of this nosology.


Assuntos
Citalopram/efeitos adversos , Glaucoma de Ângulo Fechado/induzido quimicamente , Inibidores Seletivos de Recaptação de Serotonina/efeitos adversos , Líquido Sub-Retiniano , Doenças da Úvea/induzido quimicamente , Doença Aguda , Idoso , Atropina/uso terapêutico , Tartarato de Brimonidina/uso terapêutico , Doenças da Coroide/induzido quimicamente , Doenças da Coroide/tratamento farmacológico , Corpo Ciliar/patologia , Overdose de Drogas , Emergências , Feminino , Glaucoma de Ângulo Fechado/tratamento farmacológico , Humanos , Miopia/induzido quimicamente , Prednisona/uso terapêutico , Receptores de Serotonina/efeitos dos fármacos , Receptores de Serotonina/fisiologia , Líquido Sub-Retiniano/diagnóstico por imagem , Timolol/uso terapêutico , Doenças da Úvea/tratamento farmacológico , Doenças da Úvea/fisiopatologia
12.
Proc Natl Acad Sci U S A ; 106(52): 22540-5, 2009 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-20018756

RESUMO

Auxin regulates most aspects of plant growth and development. The hormone is perceived by the TIR1/AFB family of F-box proteins acting in concert with the Aux/IAA transcriptional repressors. Arabidopsis plants that lack members of the TIR1/AFB family are auxin resistant and display a variety of growth defects. However, little is known about the functional differences between individual members of the family. Phylogenetic studies reveal that the TIR1/AFB proteins are conserved across land plant lineages and fall into four clades. Three of these subgroups emerged before separation of angiosperms and gymnosperms whereas the last emerged before the monocot-eudicot split. This evolutionary history suggests that the members of each clade have distinct functions. To explore this possibility in Arabidopsis, we have analyzed a range of mutant genotypes, generated promoter swap transgenic lines, and performed in vitro binding assays between individual TIR1/AFB and Aux/IAA proteins. Our results indicate that the TIR1/AFB proteins have distinct biochemical activities and that TIR1 and AFB2 are the dominant auxin receptors in the seedling root. Further, we demonstrate that TIR1, AFB2, and AFB3, but not AFB1 exhibit significant posttranscriptional regulation. The microRNA miR393 is expressed in a pattern complementary to that of the auxin receptors and appears to regulate TIR1/AFB expression. However our data suggest that this regulation is complex. Our results suggest that differences between members of the auxin receptor family may contribute to the complexity of auxin response.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/metabolismo , Proteínas F-Box/metabolismo , Proteínas de Plantas/metabolismo , Receptores de Superfície Celular/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Proteínas F-Box/genética , Regulação da Expressão Gênica de Plantas , Genes de Plantas/efeitos dos fármacos , Ácidos Indolacéticos/metabolismo , Ácidos Indolacéticos/farmacologia , MicroRNAs/genética , Mutação , Proteínas de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Plantas Geneticamente Modificadas , RNA de Plantas/genética , Receptores de Superfície Celular/genética , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo
13.
Arch. latinoam. nutr ; 57(1): 51-55, mar. 2007.
Artigo em Espanhol | LILACS | ID: lil-475638

RESUMO

Se evaluó el efecto de diferentes tipos de cultivos probióticos en yogurt sobre poblaciones conocidas de Staphylococcus aureus, Escherichia coli O157:H7, Listeria monocytogenes y Salmonella enteritidis. Los tres tipos diferentes de yogurt comercial utilizados fueron: sin probióticos adicionados, con probióticos CHR HANSEN® (Lactobacillus casei CRL_431 y L. acidophilus CRL_730) y otro con los mismos probióticos mencionados anteriormente, adicionado con cultivo de Lactobacillus rhamnosus (LR-35). Se inoculó aproximadamente 109 UFC/mL de cada bacteria potencialmente patógena en los diferentes tipos de yogurt, se mantuvo en refrigeración a 4ºC durante la vida útil de cada uno de estos alimentos (aproximadamente 30 días) y se realizó un recuento bacteriano cada cuatro días incluyendo el mismo día de la inoculación. Los resultados obtenidos demuestran que, existe diferencia en cuanto a inhibición entre los yogures sin probióticos y el yogurt comercial con probióticos, observándose un efecto inhibitorio evidente, por parte del segundo sobre las poblaciones de S. aureus, E. coli O157:H7 y L. monocytogenes. Con respecto a los yogures comerciales con probióticos más L. rhamnosus, no se observó alguna diferencia con respecto al efecto inhibitorio que poseen los yogures con probióticos L. casei y L. acidophilus . En los yogures en que se evaluó S. enteritidis se obtuvo la muerte de ésta al cabo de cuatro días. El presente estudio confirma el efecto antagónico que poseen los cultivos probióticos sobre bacterias potencialmente patógenas para el ser humano y animales que pueden estar contenidas en los alimentos.No obstante, el uso del probiótico Lactobacillus rhamnosus no ejerce un efecto inhibitorio adicional.


The effect of different types of probiotics present in yogurt over known populations of Staphylococcus aureus, Escherichia coli O157:H7, Listeria monocytogenes and Salmonella enteritidis was evaluated. The three types of yogurt used were: without added probiotics, with added probiotics (Lactobacillus casei CRL_431 and L. acidophilus CRL_730 CHR HANSEN®) and another one with the same probiotics mentioned above and Lactobacillus rhamnosus (LR-35) culture. About 109 CFU/ mL of each potentially pathogenic bacteria was added to each type of yogurt tested, and kept in refrigeration at 4ºC during its shelf life, about 30 days. Bacterial count was done the initial day and every four days. Results obtained show that there is a difference in the inhibition between yogurts without added probiotics and the commercial yogurt with added probiotics; there is a clear inhibitory effect of the last one over S. aureus, E coli O157:H7 and Listeria monocytogenes. The yogurt with added probiotics and L. rhamnosus did not show any additional inhibitory effect over the bacteria tested when compared with the yogurt with added probiotics. S. enteritidis could not be evaluated because it was not detectable in any yogurt samples evaluated four days after its inoculation. This study confirms the antagonic effect of probiotic cultures over potentially pathogenic bacteria for human beings and animals that may be present in food. Nevertheless, the use of L. rhamnosus did not produce any additional inhibitory effect.


Assuntos
Bactérias Gram-Positivas/efeitos dos fármacos , Enterobacteriaceae/efeitos dos fármacos , Microbiologia de Alimentos , Iogurte/microbiologia , Lacticaseibacillus rhamnosus , Probióticos/farmacologia , Contagem de Colônia Microbiana , /efeitos dos fármacos , Manipulação de Alimentos , Concentração de Íons de Hidrogênio , Listeria monocytogenes/efeitos dos fármacos , Salmonella enteritidis/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Fatores de Tempo
14.
Clin. transl. oncol. (Print) ; 8(11): 826-829, nov. 2006. tab
Artigo em Inglês | IBECS | ID: ibc-126240

RESUMO

BACKGROUND: The relationship between breast cancer and circadian rhythm variation has been extensively studied. Increased breast tumorigenesis has been reported in melatonin-suppressed experimental models and in observational studies. OBJECTIVES: Circulating Tumor Cells (CTC) circadian- rhythm may optimize the timing of therapies. This is a prospective experimental study to ascertain the day-time and night-time CTC levels in hospitalized metastasic breast cancer (MBC) patients. MATERIAL AND METHODS: TC are isolated and enumerated from a 08:00 AM and 08:00 PM blood collections. 23 MBC and 23 healthy volunteers entered the study. 69 samples were collected (23 samples at 08:00 AM and 23 samples at 08:00 PM from MBC; 23 samples from healthy volunteers). Results from two patients were rejected due to sample processing errors. No CTC were isolated from healthy-volunteers. RESULTS AND DISCUSSION: No-differences between daytime and night-time CTC were observed. Therefore, we could not ascertain CTC circadian-rhythm in hospitalized metastasic breast cancer patients (AU)


Assuntos
Humanos , Feminino , Antineoplásicos/uso terapêutico , Antineoplásicos Hormonais/uso terapêutico , Neoplasias da Mama/sangue , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Metástase Neoplásica/patologia , Ciclo Celular , Ritmo Circadiano , Receptores de Estrogênio/uso terapêutico , Estudos Prospectivos , Células Neoplásicas Circulantes
15.
J Parasitol ; 90(5): 1190-3, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15562630

RESUMO

The broad fish tapeworm, Diphyllobothrium latum, is an exotic species in both Chile and Argentina, and until now, its copepod host has remained unknown in South American waters. The objective of this study was to identify calanoid copepod species that may be intermediate hosts for D. latum in Lake Panguipulli, Chile. In this lake, the highest levels of infection by this tapeworm occur in the introduced rainbow trout, Oncorhynchus mykiss. Of the 2 calanoid copepods found in Lake Panguipulli, Diaptomus diabolicus and Boeckella gracilipes, only D. diabolicus became infected on experimental exposure to coracidia. Prevalence (mean intensity) of experimental infection in adult copepods was 73.2% (2.8 procercoids per host). Diaptomus diabolicus has been demonstrated to be a new intermediate host; this is the first record of a copepod host for D. latum in South America.


Assuntos
Copépodes/parasitologia , Difilobotríase/veterinária , Diphyllobothrium/fisiologia , Doenças dos Peixes/parasitologia , Oncorhynchus mykiss/parasitologia , Animais , Chile , Difilobotríase/parasitologia , Difilobotríase/transmissão , Vetores de Doenças , Cães , Doenças dos Peixes/transmissão , Água Doce
16.
Cell Tissue Res ; 308(2): 299-306, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-12037586

RESUMO

The ultrastructure of the body wall muscles and the intraepidermal nervous system of the Gordiida Pseudochordodes bedriagae are described. The body wall muscles are of the circomyarian type, since the sarcomeres constitute a system of continuous peripheral helices. The organisation of the sarcomeres follows a pattern that resembles that of the striated muscles. The muscle fibres are separated into areas by invaginations formed exclusively by the plasma membrane (T component), while the sarcoplasmic reticulum lies at the sides of the Z granules forming subsarcolemmal cisternae, and in the zone near the nucleus, like flattened vesicles, contributing with the T component to the formation of dyads and triads. The muscle fibres present two types of adaptations for their innervation: (1) cytoplasmic projections towards the epidermis, and (2) invaginations of the plasmalemma. The motor peripheral nervous system is conformed by the nerve fibres that run within the epidermis and their projections towards the basal membrane in order to contact the adaptations of the muscle fibres in a basi-epidermal synapsis. The presence of an intraepithelial peripheral nervous system in Gordiida confirms a structural pattern common to other taxa of Nemathelminthes.


Assuntos
Epiderme/inervação , Helmintos/ultraestrutura , Músculos/ultraestrutura , Sistema Nervoso/ultraestrutura , Animais , Axônios/ultraestrutura , Membrana Celular/ultraestrutura , Epiderme/ultraestrutura , Matriz Extracelular/ultraestrutura , Técnicas In Vitro , Masculino , Microscopia Eletrônica , Microscopia Eletrônica de Varredura , Contração Muscular/fisiologia , Fibras Musculares Esqueléticas/ultraestrutura , Músculos/inervação , Sistema Nervoso Periférico/ultraestrutura , Sarcolema/ultraestrutura
17.
Parasite ; 9(1): 71-4, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11938699

RESUMO

There are many species of Nematomorpha which are deficiently described and therefore pose doubts about their actual taxonomic position. This is the case with Spinochordodes tellinii (Comerano, 1888), which was transferred to four different genera and has been recently considered as species incertae sedis. A female of Spinochordodes tellinii is redescribed in this work under light microscopy and Scanning Electron Microscopy. Cuticle details, shapes and areolar distribution and the features as well as the location of spiniform structures are analysed. The systematic position is discussed.


Assuntos
Helmintos/ultraestrutura , Animais , Feminino , Helmintos/classificação , Microscopia Eletrônica de Varredura , Especificidade da Espécie
18.
Cell Tissue Res ; 305(1): 129-34, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11512665

RESUMO

The light-microscopic and ultrastructural characteristics of Nematomorpha (Gordiacea) integument are described. Nine male Pseudochordodes bedriagae specimens were collected in the 1997 spring-summer period from the Sauce Chico stream in the Sierra de la Ventana, province of Buenos Aires, Argentina. Of these samples, two were analyzed using scanning electron microscopy (SEM) and the other two using transmission electron microscopy (TEM) in order to establish their morphological characteristics. The morphology of the three integumentary components (epidermis, cuticle and epicuticle) is described. Comparing our findings with those of previous studies, numerous similarities are pointed out. Some variants found would probably be related more to the various criteria of interpreting cut incidences and/or fractures than to actual differences. We assume that the different zones of the cuticle and epicuticle are segregated at the germinal stratum level by the epidermal cells, which would later undergo a slow process of maturation until their exocytosis at the level of the free epicuticular surface.


Assuntos
Epiderme/ultraestrutura , Helmintos/ultraestrutura , Animais , Argentina , Masculino , Microscopia Eletrônica de Varredura
19.
J Psychother Pract Res ; 9(3): 131-5, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10896737

RESUMO

There has been much outcome research on interpersonal psychotherapy (IPT) but little investigation of its components. This study assessed interrater reliability of IPT therapists in identifying interpersonal problem areas and treatment foci from audiotapes of initial treatment sessions. Three IPT research psychotherapists assessed up to 18 audiotapes of dysthymic patients, using the Interpersonal Problem Area Rating Scale. Cohen's kappa was used to examine concordance between raters. Kappas for presence or absence of each of the four IPT problem areas were 0.87 (grief), 0.58 (role dispute), 1.0 (role transition), and 0.48 (interpersonal deficits). Kappa for agreement on a clinical focus was 0.82. IPT therapists agreed closely in rating problem areas and potential treatment foci, providing empirical support for potential therapist consistency in this treatment approach.


Assuntos
Transtorno Distímico/terapia , Avaliação de Processos e Resultados em Cuidados de Saúde/estatística & dados numéricos , Relações Profissional-Paciente , Psicoterapia , Adulto , Transtorno Distímico/psicologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Psicometria , Psicoterapia/métodos
20.
Sleep Res Online ; 2(2): 33-41, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-11382880

RESUMO

Blood adenosine metabolism, including metabolites and metabolizing enzymes, was studied during the sleep period in human volunteers. Searching for significant correlations among biochemical parameters found: adenosine with state 1 of slow-wave sleep (SWS); activity of 5'-nucleotidase with state 2 of SWS; inosine and AMP with state 3-4 of SWS; and activity of 5'-nucleotidase and lactate with REM sleep. The correlations were detected in all of the subjects that presented normal hypnograms, but not in those who had fragmented sleep the night of the experiment. The data demonstrate that it is possible to obtain information of complex brain operations such as sleep by measuring biochemical parameters in blood. The results strengthen the notion of a role played by adenosine, its metabolites and metabolizing enzymes, during each of the stages that constitute the sleep process in humans.


Assuntos
Adenosina/sangue , Fases do Sono/fisiologia , Adenosina/metabolismo , Adulto , Análise de Variância , Ritmo Circadiano/fisiologia , Humanos , Masculino , Polissonografia , Sono REM/fisiologia
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