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1.
AJNR Am J Neuroradiol ; 44(9): 1020-1025, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37562826

RESUMEN

BACKGROUND AND PURPOSE: The nucleus basalis of Meynert is a key subcortical structure that is important in arousal and cognition and has been explored as a deep brain stimulation target but is difficult to study due to its small size, variability among patients, and lack of contrast on 3T MR imaging. Thus, our goal was to establish and evaluate a deep learning network for automatic, accurate, and patient-specific segmentations with 3T MR imaging. MATERIALS AND METHODS: Patient-specific segmentations can be produced manually; however, the nucleus basalis of Meynert is difficult to accurately segment on 3T MR imaging, with 7T being preferred. Thus, paired 3T and 7T MR imaging data sets of 21 healthy subjects were obtained. A test data set of 6 subjects was completely withheld. The nucleus was expertly segmented on 7T, providing accurate labels for the paired 3T MR imaging. An external data set of 14 patients with temporal lobe epilepsy was used to test the model on brains with neurologic disorders. A 3D-Unet convolutional neural network was constructed, and a 5-fold cross-validation was performed. RESULTS: The novel segmentation model demonstrated significantly improved Dice coefficients over the standard probabilistic atlas for both healthy subjects (mean, 0.68 [SD, 0.10] versus 0.45 [SD, 0.11], P = .002, t test) and patients (0.64 [SD, 0.10] versus 0.37 [SD, 0.22], P < .001). Additionally, the model demonstrated significantly decreased centroid distance in patients (1.18 [SD, 0.43] mm, 3.09 [SD, 2.56] mm, P = .007). CONCLUSIONS: We developed the first model, to our knowledge, for automatic and accurate patient-specific segmentation of the nucleus basalis of Meynert. This model may enable further study into the nucleus, impacting new treatments such as deep brain stimulation.


Asunto(s)
Núcleo Basal de Meynert , Aprendizaje Profundo , Humanos , Imagen por Resonancia Magnética/métodos , Encéfalo , Cognición
2.
Leukemia ; 32(10): 2305, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-30218008

RESUMEN

Following the publication of this article, the authors noted that the pomalidomide dose for the additional SC cohort in Fig. 1 was incorrectly listed. The correct dose for pomalidomide in the additional SC cohort should be the maximum tolerated dose of 4 mg/day, not 2 mg/day as listed in the original Fig. 1. The authors apologize for any inconvenience caused.

3.
Leukemia ; 31(12): 2695-2701, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-28642620

RESUMEN

This phase 1 dose-escalation study evaluated pomalidomide, bortezomib (subcutaneous (SC) or intravenous (IV)) and low-dose dexamethasone (LoDEX) in lenalidomide-refractory and proteasome inhibitor-exposed relapsed or relapsed and refractory multiple myeloma (RRMM). In 21-day cycles, patients received pomalidomide (1-4 mg days 1-14), bortezomib (1-1.3 mg/m2 days 1, 4, 8 and 11 for cycles 1-8; days 1 and 8 for cycle ⩾9) and LoDEX. Primary endpoint was to determine the maximum tolerated dose (MTD). Thirty-four patients enrolled: 12 during escalation, 10 in the MTD IV bortezomib cohort and 12 in the MTD SC bortezomib cohort. Patients received a median of 2 prior lines of therapy; 97% bortezomib exposed. With no dose-limiting toxicities, MTD was defined as the maximum planned dose: pomalidomide 4 mg, bortezomib 1.3 mg/m2 and LoDEX. All patients discontinued treatment by data cutoff (2 April 2015). The most common grade 3/4 treatment-emergent adverse events were neutropenia (44%) and thrombocytopenia (26%), which occurred more frequently with IV than SC bortezomib. No grade 3/4 peripheral neuropathy or deep vein thrombosis was reported. Overall response rate was 65%. Median duration of response was 7.4 months. Pomalidomide, bortezomib and LoDEX was well tolerated and effective in lenalidomide-refractory and bortezomib-exposed patients with RRMM.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Mieloma Múltiple/tratamiento farmacológico , Adulto , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Biomarcadores , Bortezomib/administración & dosificación , Dexametasona/administración & dosificación , Resistencia a Antineoplásicos , Femenino , Humanos , Lenalidomida , Masculino , Dosis Máxima Tolerada , Persona de Mediana Edad , Mieloma Múltiple/mortalidad , Mieloma Múltiple/patología , Estadificación de Neoplasias , Inhibidores de Proteasoma/administración & dosificación , Inhibidores de Proteasoma/uso terapéutico , Retratamiento , Talidomida/administración & dosificación , Talidomida/análogos & derivados , Talidomida/uso terapéutico , Resultado del Tratamiento
4.
BMC Evol Biol ; 16: 41, 2016 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-26892684

RESUMEN

BACKGROUND: The Oriental fruit bat genus Cynopterus, with several geographically overlapping species, presents an interesting case study to evaluate the evolutionary significance of coexistence versus isolation. We examined the morphological and genetic variability of congeneric fruit bats Cynopterus sphinx and C. brachyotis using 405 samples from two natural contact zones and 17 allopatric locations in the Indian subcontinent; and investigated the population differentiation patterns, evolutionary history, and the possibility of cryptic diversity in this species pair. RESULTS: Analysis of microsatellites, cytochrome b gene sequences, and restriction digestion based genome-wide data revealed that C. sphinx and C. brachyotis do not hybridize in contact zones. However, cytochrome b gene sequences and genome-wide SNP data helped uncover a cryptic, hitherto unrecognized cynopterine lineage in northeastern India coexisting with C. sphinx. Further analyses of shared variation of SNPs using Patterson's D statistics suggest introgression between this lineage and C. sphinx. Multivariate analyses of morphology using genetically classified grouping confirmed substantial morphological overlap between C. sphinx and C. brachyotis, specifically in the high elevation contact zones in southern India. CONCLUSION: Our results uncover novel diversity and detect a pattern of genetic introgression in a cryptic radiation of bats, demonstrating the complicated nature of lineage diversification in this poorly understood taxonomic group. Our results highlight the importance of genome-wide data to study evolutionary processes of morphologically similar species pairs. Our approach represents a significant step forward in evolutionary research on young radiations of non-model species that may retain the ability of interspecific gene flow.


Asunto(s)
Quirópteros/genética , Flujo Génico , Variación Genética , Filogenia , Animales , Evolución Biológica , Quirópteros/fisiología , Citocromos b/genética , Fenómenos de Retorno al Lugar Habitual , Hibridación Genética , India , Repeticiones de Microsatélite , Análisis Multivariante , Polimorfismo de Nucleótido Simple , Especificidad de la Especie
5.
Integr Med Res ; 5(4): 276-283, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28462129

RESUMEN

BACKGROUND: Oxidative stress induced tissue damage might be the major cause for diabetes mellitus and its associated complications. The management of such oxidative stress is the biggest challenge over the decade. The main objective was to analyze the protective effect of ethanolic extract of Senna alata L leaves on enzymatic and nonenzymatic antioxidant systems of hepatic and renal tissues in Streptozotocin-induced diabetes in rats. METHODS: The use of streptozotocin diabetes was induced in the experimental rats and the subsequent therapeutic effects of standard drug glibenclamide and Senna alata L were compared. The levels of plasma insulin, glucose, urea, uric acid, creatinine, vitamin C, vitamin E, reduced glutathione, superoxide dismutase, catalase, glutathione peroxidase, and glutathione-s-tranferase were assayed in control and experimental groups of rats. RESULTS: These alterations were detected throughout the study duration after the treatment with Senna alata L and glibenclamide. A significant raise followed by the treatment with Senna alata leaves in vitamin E, catalase, glutathione peroxidase and glutathione-s-tranferase was observed. It has been found that notable decline in the levels of vitamin C, reduced glutathione were observed in diabetic rats. The liver and kidney based antioxidant enzyme activities were significantly responsive to the treatment in diabetic rats. Apart from these antioxidant system, some vital changes were detected in the typical biochemical parameters such as level of protein, urea, uric acid, and creatinine from abnormal into normal in both the control and induced rats. CONCLUSION: From the above said observations, it was very clear that, Senna alata has helped to manage the oxidative tension in diabetic rats, which in turn may greatly support the hypoglycaemic potency of Senna alata L.

6.
PLoS One ; 10(3): e0122180, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25794185

RESUMEN

Sociality emerges when the benefits of group living outweigh its costs. While both males and females are capable of strong social ties, the evolutionary drivers for sociality and the benefits accrued maybe different for each sex. In this study, we investigate the differential reproductive success benefits of group membership that males and females might obtain in the promiscuous fruit bat Cynopterus sphinx. Individuals of this species live in flexible social groups called colonies. These colonies are labile and there is high turnover of individuals. However, colony males sire more offspring within the colony suggesting that being part of a colony may result in reproductive benefits for males. This also raises the possibility that long-term loyalty towards the colony may confer additional advantage in terms of higher reproductive success. We used ten seasons of genetic parentage data to estimate reproductive success and relatedness of individuals in the colony. We used recapture data to identify long and short-term residents in the colony as well as to obtain rates of recapture for males and females. Our results reveal that males have a significantly higher chance of becoming long-term residents (than females), and these long-term resident males gain twice the reproductive success compared to short-term resident males. We also observed that long-term resident females are related to each other and also achieve higher reproductive success than short-term resident females. In contrast, long-term resident males do not differ from short-term resident males in their levels of relatedness. Our results re-iterate the benefits of sociality even in species that are promiscuous and socially labile and possible benefits of maintaining a colony.


Asunto(s)
Quirópteros/fisiología , Conducta Sexual Animal , Conducta Social , Animales , Femenino , Masculino , Reproducción , Estaciones del Año
7.
Mol Ecol ; 21(16): 4093-105, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22725709

RESUMEN

Observations on mating behaviours and strategies guide our understanding of mating systems and variance in reproductive success. However, the presence of cryptic strategies often results in situations where social mating system is not reflective of genetic mating system. We present such a study of the genetic mating system of a harem-forming bat Cynopterus sphinx where harems may not be true indicators of male reproductive success. This temporal study using data from six seasons on paternity reveals that social harem assemblages do not play a role in the mating system, and variance in male reproductive success is lower than expected assuming polygynous mating. Further, simulations reveal that the genetic mating system is statistically indistinguishable from promiscuity. Our results are in contrast to an earlier study that demonstrated high variance in male reproductive success. Although an outcome of behavioural mating patterns, standardized variance in male reproductive success (I(m)) affects the opportunity for sexual selection. To gain a better understanding of the evolutionary implications of promiscuity for mammals in general, we compared our estimates of I(m) and total opportunity for sexual selection (I(m) /I(f), where I(f) is standardized variance in female reproductive success) with those of other known promiscuous species. We observed a broad range of I(m) /I(f) values across known promiscuous species, indicating our poor understanding of the evolutionary implications of promiscuous mating.


Asunto(s)
Quirópteros/fisiología , Conducta Sexual Animal , Animales , Quirópteros/genética , Femenino , India , Masculino , Repeticiones de Microsatélite , Paternidad , Selección Genética
8.
Qual Life Res ; 11(8): 783-96, 2002 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-12482162

RESUMEN

OBJECTIVE: We sought to describe and find correlates of health-related quality of life among under-served low-income patients in North Carolina with diabetes mellitus. METHODS: A telephone survey of 310 patients recording quality of life, patient satisfaction, self-reported health, and patient complaints was conducted as part of a diabetes care improvement project. Demographic and clinical records were available for 249 of these patients: 69% were female, 45% were minority, and 84% had type 2 diabetes. Ages ranged from 18 to 88 years with a mean of 56. Quality of life indices consisted of SF-36 physical functioning, mental health and diabetes-39 sub-scores. RESULTS: Comparison to SF-36 norms showed the sample had lower sub-scores than expected. The multivariate analysis suggested that being within an acceptable metabolic control predicted better quality of life physically, mentally, and sexually. Strong associations were detected between most sub-scores and complaints involving legs and feet, self-rated vision, and hassles in self-management. CONCLUSIONS: The consistent associations between the sub-scores and complaints, symptoms, and hassles underscore the strong relationship quality of life may share with the severity of diabetes complications as well as with psychosocial factors. Significantly lower quality of life in this sample highlights the need to improve the care of minority low-income diabetes patients.


Asunto(s)
Diabetes Mellitus Tipo 1/fisiopatología , Diabetes Mellitus Tipo 2/fisiopatología , Pobreza , Calidad de Vida , Perfil de Impacto de Enfermedad , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Diabetes Mellitus Tipo 1/etnología , Diabetes Mellitus Tipo 1/psicología , Diabetes Mellitus Tipo 2/etnología , Diabetes Mellitus Tipo 2/psicología , Femenino , Estado de Salud , Humanos , Masculino , Persona de Mediana Edad , Análisis Multivariante , North Carolina
9.
Blood ; 98(4): 934-9, 2001 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-11493435

RESUMEN

Previous trials of allogeneic bone marrow transplantation (BMT) in patients with multiple myeloma (MM) have demonstrated high response rates but also high transplantation-related mortality (TRM) and high relapse rates. Exploitation of this strategy remains of interest because donor lymphocyte infusions (DLIs) can induce a potent graft-versus-myeloma (GVM) effect. CD6 T-cell--depleted allogeneic BMT was combined with prophylactic CD4(+) DLI administered 6 to 9 months after BMT in an effort to reduce TRM and to induce a GVM response after BMT. Twenty-four patients with matched sibling donors and chemotherapy-sensitive disease underwent BMT. CD6 T-cell depletion of donor bone marrow was the sole method of graft-versus-host disease (GVHD) prophylaxis. GVHD after BMT was minimal, 1 (4%) grade III and 4 (17%) grade II GVHD. Fourteen patients received DLI, 3 in complete response and 11 with persistent disease after BMT. Significant GVM responses were noted after DLI in 10 patients with persistent disease, resulting in 6 complete responses and 4 partial responses. After DLI, 50% of patients developed acute (> or = II) or extensive chronic GVHD. Two-year estimated overall survival and current progression-free survival (PFS) for all 24 patients is 55% and 42%, respectively. The 14 patients receiving DLI had an improved 2-year current PFS (65%) when compared with a historical cohort of MM patients who underwent CD6-depleted BMT survived 6 months with no GVHD and did not receive DLI (41%) (P =.13). Although this study suggests that prophylactic DLI induces significant GVM responses after allogeneic BMT, only 58% of patients were able to receive DLI despite T-cell--depleted BMT. Therefore, less toxic transplantation strategies are needed to allow a higher proportion of patients to receive DLI and the benefit from the GVM effect after transplantation. (Blood. 2001;98:934-939)


Asunto(s)
Trasplante de Médula Ósea/métodos , Depleción Linfocítica/normas , Transfusión de Linfocitos/normas , Mieloma Múltiple/terapia , Análisis Actuarial , Adulto , Antígenos CD/análisis , Antígenos de Diferenciación de Linfocitos T/análisis , Trasplante de Médula Ósea/efectos adversos , Linfocitos T CD4-Positivos/trasplante , Supervivencia sin Enfermedad , Femenino , Efecto Injerto vs Tumor/fisiología , Humanos , Masculino , Persona de Mediana Edad , Mieloma Múltiple/diagnóstico , Pronóstico , Linfocitos T/inmunología , Trasplante Homólogo/efectos adversos , Trasplante Homólogo/métodos
10.
J Immunother ; 24(3): 263-71, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11394505

RESUMEN

The anti-CD20 chimeric monoclonal antibody rituximab (Rituxan) is used to treat patients with various B-cell tumors, including patients with plasma cell dyscrasias who have CD20+ disease. Many patients with CD20+ disease have either primary unresponsive disease or progress after initially responding to rituximab; therefore, understanding how tumor cells are, or become, resistant to rituximab is of clinical relevance. In this report, we determined whether tumor cells express antigens that block complement-mediated lysis or antibody-dependent cell-mediated cytotoxicity (ADCC) and thereby contribute to rituximab resistance. We demonstrate that expression of the complement regulator CD59 is associated with resistance to rituximab-mediated complement lysis of multiple myeloma (MM) and non-Hodgkin's lymphoma (NHL) cell lines. Moreover, neutralization of CD59 using a blocking monoclonal antibody reversed resistance to rituximab-mediated complement lysis of CD20++ CD59++ ARH-77 MM cells. In addition, we demonstrate the presence of CD59 and rituximab binding on viable tumor cells from patients with MM and Waldenstrom's macroglobulinemia with progressive disease despite rituximab therapy. Last, we also examined MM and NHL B-cell lines, as well as patient tumor cells, for the expression of other antigens that may have a role in blocking ADCC activity, such as Fas ligand (FasL), MUCI, or TRAIL. FasL, MUC1, and/or TRAIL were coexpressed with complement regulators on many of these cells. These studies therefore show that complement regulators, particularly CD59 and antigens that may block ADCC, are present on various B-cell tumors and associated with rituximab resistance in patients. A prospective, clinical study is assessing the role of these antigens in mediating rituximab resistance.


Asunto(s)
Anticuerpos Monoclonales/uso terapéutico , Antígenos CD59/metabolismo , Linfoma de Células B/inmunología , Linfoma de Células B/terapia , Animales , Anticuerpos Monoclonales de Origen Murino , Citotoxicidad Celular Dependiente de Anticuerpos , Antígenos CD20/metabolismo , Proteínas Reguladoras de la Apoptosis , Linfocitos B/inmunología , Proteína Ligando Fas , Humanos , Técnicas In Vitro , Linfoma no Hodgkin/inmunología , Linfoma no Hodgkin/terapia , Glicoproteínas de Membrana/inmunología , Ratones , Mucina-1/inmunología , Mieloma Múltiple/inmunología , Mieloma Múltiple/terapia , Pruebas de Neutralización , Fragmentos de Péptidos/inmunología , Rituximab , Ligando Inductor de Apoptosis Relacionado con TNF , Células Tumorales Cultivadas , Factor de Necrosis Tumoral alfa/inmunología , Macroglobulinemia de Waldenström/inmunología , Macroglobulinemia de Waldenström/terapia
11.
J Biomech Eng ; 122(3): 283-6, 2000 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10923297

RESUMEN

The extent of the change in thermal diffusivity of soft tissues due to heat-induced damage is not well known. Reported here are the results of using the flash method to measure the through-the-wall component of thermal diffusivity of bovine aorta before and after the tissue has undergone two hours of heating at 75 degrees C. The measurements indicate a 10.1 percent increase in the thermal diffusivity of the tissue post-heating. While this change may not result in a significant change in the tissue temperature profile, further study is needed to quantify the thermal diffusivity in other coordinate directions, as well as the mechanisms by which this change in properties occurs.


Asunto(s)
Aorta/lesiones , Aorta/fisiología , Quemaduras/fisiopatología , Conductividad Térmica , Animales , Bovinos , Temperatura , Factores de Tiempo
12.
Semin Oncol ; 26(5 Suppl 14): 97-106, 1999 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-10561024

RESUMEN

The use of serotherapy to treat patients with plasma cell dyscrasias (PCDs) has been sought by us and others. Candidate antigens that have been targeted or proposed for targeting in PCDs include the immunoglobulin idiotype, CD19, CD38, CD54, CD126, HM1.24, and Muc-1 core protein. Unfortunately, many of these antigens are not ideal for use in serotherapy since they are not selectively expressed, are either shed or secreted, or have not been fully characterized. Serotherapy with an anti-CD19 monoclonal antibody (B4) conjugated to a blocked ricin toxin had no significant activity in patients with multiple myeloma (MM). Circulating CD20+ clonotypic B cells have been detected in the circulation of most MM and Waldenstrom's macroglobulinemia (WM) patients. Plasma cells from most WM patients express CD20, but most MM patient plasma cells either lack CD20 or express it weakly. In view of recent successes with anti-CD20-directed serotherapy in other B-cell malignancies, we initiated a phase II trial to study the anti-CD20 monoclonal antibody rituximab (Rituxan; IDEC Pharmaceuticals, San Diego, CA, and Genentech, Inc, San Francisco, CA) in patients with MM. We describe two PCD patients (one with WM and one with MM) who responded to therapy. By flow cytometric analysis, CD20+ plasma cells and B cells present in the bone marrow and peripheral blood of a patient with MM disappeared with response to rituximab therapy. However, residual CD20- tumor cells remained in the bone marrow following rituximab therapy, and after 6 months this patient progressed with CD20- myeloma cells. As a potential strategy to overcome this limitation, we demonstrated that interferon-gamma at pharmacologically achievable levels induced CD20 expression on these CD20- plasma cells, consistent with our recent findings that interferon-gamma is a potent inducer of CD20 expression on MM patient plasma cells and B cells. We also characterize a response to rituximab with a decrease in paraprotein and resolution of anemia in a patient with WM whose response to rituximab is ongoing after 19+ months. This preliminary experience supports the potential use of serotherapy targeting CD20 in PCDs. Our studies further suggest that interferon-gamma may enhance CD20 expression on MM plasma cells, thereby increasing their susceptibility to anti-CD20 monoclonal antibody therapies.


Asunto(s)
Anticuerpos Monoclonales/uso terapéutico , Antineoplásicos/uso terapéutico , Factores Inmunológicos/uso terapéutico , Mieloma Múltiple/tratamiento farmacológico , Macroglobulinemia de Waldenström/tratamiento farmacológico , Anciano , Anticuerpos Monoclonales de Origen Murino , Antígenos CD20/biosíntesis , Linfocitos B/inmunología , Ensayos Clínicos Fase II como Asunto , Citometría de Flujo , Humanos , Inmunización Pasiva , Interferón gamma/farmacología , Masculino , Mieloma Múltiple/inmunología , Mieloma Múltiple/patología , Paraproteinemias/tratamiento farmacológico , Paraproteinemias/inmunología , Fenotipo , Rituximab , Macroglobulinemia de Waldenström/inmunología , Macroglobulinemia de Waldenström/patología
13.
Altern Ther Health Med ; 5(4): 51-6, 1999 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10394674

RESUMEN

CONTEXT: The actual identification (let alone measurement) of "healing energy" has been elusive and controversial. Although healing energy has been defined as "subtle" and "undetectable," preliminary research indicates that these descriptions may be inaccurate. OBJECTIVE: To assess the fluctuation of extremely high-frequency electromagnetic fields, or gamma rays, during Polarity therapy treatment. DESIGN: A series of gamma detection rate experiments were performed to establish a background and baseline count rate among 10 treatment and 20 control (10 sham and 10 standing-observer) subjects. SETTING: The Columbus Polarity Therapy Institute in Columbus, Ohio, and Public Health Information Services, Inc, in Dublin, Ohio. PARTICIPANTS: 30 volunteers recruited from Polarity and nonparticipant groups. INTERVENTION: Polarity therapy, a holistic bioenergy modality. MAIN OUTCOME MEASURES: The detection rate at 4 anatomical locations in space relative to each subject's body was measured using an Nal(Tl) gamma radiation detector operated in integral count mode. RESULTS: Marked decreases in gamma counts were found at every anatomical site location for all subjects during Polarity therapy, with less change noted during the standing-observer and sham sessions. Gamma radiation decreased in 100% of subjects during therapy sessions at every body site tested, regardless of which therapist performed the treatment. CONCLUSIONS: This preliminary study suggests a consistent and dramatic decrease in the number of gamma rays measured in a subject's electromagnetic field during one type of alternative healing energy treatment (Polarity therapy). The authors strongly recommend the collection of additional data, especially on subjects with cancer, whose long-term survival might be enhanced as a result of the radiation hormesis effects of alternative energy therapies.


Asunto(s)
Terapias Complementarias , Rayos gamma , Humanos
14.
Cytotherapy ; 1(3): 175-82, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-12881173

RESUMEN

BACKGROUND: Wide ranges i n cell recovery and purity may be observed following CD34(+) cell selection of mobilized HPC componetns. Characteristics of the mobilized HPC, associated with isolation of a high CD34(+) cell yield and purity following cell selection, have yet to be defined. METHODS: Cell number and purities were determined before and after 56 CD34(+) cell-selection procedures, performed using the CellPro Ceprate SC system from April 1997 to February 1998. HPC were collected from 28 patients with multiple myeloma, following cyclophosphamide (60mg/kg) and G-CSF (10microg/kg) mobilization. RESULTS: A medium of 47.9% (range 1.5-109.6%) CD34(+) cells were recovered in the enriched (ENR) fraction. A linear correlation existed between total CD34(+) cells in the ENR fraction and total CD34(+) cells in the START fraction (R2=0.93); there was a logarithmic correlation between CD34 ENR fraction purity and START fraction purity (R2=0.73). A START CD34(+) cell purity > 0.42% improved purity in the ENR fraction. A median of one (range one to nine) procedure was required to isolate 2 x 10 6 CD34(+) cells/kg. Three patients pretreated with alkylating agents failed to mobilized adequate numbers of HPC. DISCUSSION: Isolation of highly purified CD34(+) cell-selected components using the Ceprate SC system in dependent on the CD34(+) purity of the lekapheresis component collected. Mobilization regimens should be used to maximize CD34(+) cell purity in stem cell authografts if CD34(+) cell selection is to be performed. Similar strategies should be used to evaluate other cell-selection devices as they become available.


Asunto(s)
Antígenos CD34/biosíntesis , Movilización de Célula Madre Hematopoyética/métodos , Trasplante de Células Madre Hematopoyéticas/métodos , Mieloma Múltiple/terapia , Adulto , Anciano , Femenino , Células Madre Hematopoyéticas/citología , Humanos , Leucaféresis , Masculino , Persona de Mediana Edad , Mieloma Múltiple/sangre , Células Madre/citología , Factores de Tiempo
15.
Ann N Y Acad Sci ; 858: 88-97, 1998 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-9917810

RESUMEN

The flash thermal diffusivity measurement technique is applied to tissue for the first time. Making use of its minimal contact with the specimen, the flash technique is extended to allow for well-defined, biaxial, finite strain. As an example application, the radial component of thermal diffusivity of bovine descending aorta is measured in vitro as a function of equibiaxial stretch, at room temperature. Data analysis is accomplished using a Marquardt algorithm coupled with a finite difference solution of the thermal diffusion equation. Extension of this method to measure simultaneously three orthogonal components of diffusivity, at different levels of temperature, is discussed.


Asunto(s)
Aorta Abdominal/fisiología , Regulación de la Temperatura Corporal , Músculo Liso Vascular/fisiología , Algoritmos , Animales , Temperatura Corporal , Bovinos , Difusión , Técnicas In Vitro , Microscopía por Video , Modelos Teóricos , Soluciones , Conductividad Térmica
16.
J Peripher Nerv Syst ; 2(2): 155-63, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-10959229

RESUMEN

The pathogenesis of experimental diabetic neuropathy is associated with the development of endoneurial hypoxia. Exposure of normal rats to hypoxic conditions has previously been shown to reduce nerve conduction velocity. To study the biochemical effects of hypoxia further, streptozotocin-induced diabetic and age-matched nondiabetic rats were maintained in air containing 10% oxygen for nine weeks. As compared to nondiabetic rats kept in room air, sciatic nerve Na,K-ATPase activity was decreased 38% in nondiabetic, hypoxic rats and tended to be lower in diabetic animals maintained in a normoxic environment. However, the enzyme activity was unchanged in diabetic, hypoxic rats, suggesting the existence of an undefined compensatory interaction between these two conditions. Arachidonoyl-containing molecular species (ACMS) of phosphatidylcholine and phosphatidylethanolamine were substantially depleted in nerves from diabetic rats. Hypoxia alone also caused a lesser depletion of some but not all of these ACMS. However, the two conditions together did not produce a further decrease, consistent with the concept that the same mechanism is responsible for loss of ACMS in hypoxia and diabetes. To examine the effects of severity of diabetes on these parameters, groups of rats were injected with either 50 mg/kg or 100 mg/kg streptozotocin. The latter group was maintained by administration of minimal insulin doses and the experiment was terminated after 3 weeks. Serum glucose in rats that received the high dose of drug averaged 12% higher than in the low dose group. As compared to nondiabetic rats, Na,K-ATPase activity was reduced 32-36%, but there was no difference in activity between the two diabetic groups. However, there was a greater loss of ACMS in the more severely hyperglycemic rats. In rats that received comparable streptozotocin doses, measurement of ACMS depletion after 3, 9 and 32 weeks of diabetes revealed the loss is progressive with time. Thus, glycerophospholipid ACMS is a sensitive index of the severity and duration of experimental diabetic neuropathy.


Asunto(s)
Diabetes Mellitus Experimental/complicaciones , Diabetes Mellitus Experimental/metabolismo , Hipoxia/etiología , Fosfatidilcolinas/metabolismo , Fosfatidiletanolaminas/metabolismo , Nervio Ciático/metabolismo , ATPasa Intercambiadora de Sodio-Potasio/metabolismo , Animales , Diabetes Mellitus Experimental/enzimología , Diabetes Mellitus Experimental/fisiopatología , Hiperglucemia/enzimología , Hiperglucemia/etiología , Hiperglucemia/metabolismo , Masculino , Ratas , Ratas Sprague-Dawley , Nervio Ciático/enzimología
17.
Anesth Analg ; 81(1): 30-4, 1995 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-7541185

RESUMEN

In the nonfailing heart, normovolemic hemodilution increases cardiac output and decreases total peripheral resistance (TPR). Putative mechanisms mediating the decrease in TPR include reflex vasodilation and changes in the local regulation of blood flow. Our objectives were to determine whether ablation of reflex neural mechanisms or the inhibition of nitric oxide (NO) synthase, the enzyme responsible for the synthesis of the endothelium-derived relaxing factor (EDRF-NO), modulates the systemic vasodilator response to normovolemic hemodilution. Three groups of male Sprague-Dawley rats were subjected to acute normovolemic hemodilution, which was achieved by exchanging a volume of blood equivalent to 3.8% of body weight with hydroxyethyl starch. Hemodilution increased cardiac output and decreased TPR. Subsequent administration of the NO synthase inhibitor, L-nitroarginine (LNA), returned both cardiac output and TPR to control values. Pretreatment with LNA prior to hemodilution increased TPR, an effect that was partially reversed by the NO donor, sodium nitroprusside. In this setting, hemodilution failed to decrease TPR. After spinal cord destruction by "pithing," hemodilution decreased TPR to the same extent as that observed in intact rats. This hemodilution-induced decrease in TPR was abolished by the subsequent administration of LNA. These results indicate that neural reflexes do not modulate the systemic vascular response to hemodilution. Moreover, the systemic vasodilator response to hemodilution is abolished after inhibition of endogenous NO synthesis.


Asunto(s)
Hemodilución , Vasodilatación/fisiología , Aminoácido Oxidorreductasas/antagonistas & inhibidores , Animales , Arginina/análogos & derivados , Arginina/farmacología , Circulación Sanguínea/efectos de los fármacos , Circulación Sanguínea/fisiología , Presión Sanguínea/efectos de los fármacos , Presión Sanguínea/fisiología , Volumen Sanguíneo , Gasto Cardíaco/efectos de los fármacos , Gasto Cardíaco/fisiología , Estado de Descerebración , Frecuencia Cardíaca/efectos de los fármacos , Frecuencia Cardíaca/fisiología , Derivados de Hidroxietil Almidón/administración & dosificación , Masculino , Óxido Nítrico/farmacología , Óxido Nítrico Sintasa , Nitroarginina , Nitroprusiato/farmacología , Ratas , Ratas Sprague-Dawley , Reflejo , Médula Espinal/fisiología , Volumen Sistólico/efectos de los fármacos , Volumen Sistólico/fisiología , Resistencia Vascular/efectos de los fármacos , Resistencia Vascular/fisiología
18.
J Mol Cell Cardiol ; 26(4): 425-34, 1994 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8072000

RESUMEN

The effects of fentanyl on ultrastructure, protein biosynthesis, and atrial natriuretic peptide (ANP) secretion were studied in neonatal rat cardiomyocytes (CM). Ventricles from 2-day-old American Wistar rats were digested with 1% collagenase in perfusion buffer. Eight hundred thousand to 1.0 million cells/ml were incubated in tissue culture media, to which fentanyl citrate (Sublimaze) was added in a dose of 10-50 ng/ml. Fentanyl increased the spontaneous CM beating rate, which became rather fibrillary in nature. Protein biosynthesis also increased in a time-related manner. Simultaneous incubation with naloxone (10(-6) M) did not alter the beating rate or protein synthesis. Ultrastructurally, several criteria of myocyte growth were observed: an increase in myofilaments and the appearance of newly formed organized sarcomeres, which were preceded by an increase in the ribosomes and cisternae of rough endoplasmic reticulum, and the appearance of large, adult-type mitochondria with increased matrix granules and long parallel cristae. The latter replaced the elongated thin fetal mitochondria. This was associated with a network of developing sarcoplasmic reticulum and T-tubular system as well as the formation of intercalated discs between the CM. Furthermore, exposure to fentanyl increased ANP immunoreactivity in the culture media while simultaneous incubation with naloxone blocked the effect of fentanyl on ANP secretion. On the other hand, naloxone alone did not alter ANP secretion. Therefore, it could be concluded that fentanyl stimulated protein biosynthesis and ANP secretion as evidenced both biochemically and ultrastructurally. Although the molecular mechanism of ANP secretion by fentanyl is still unclear, yet an opioid receptor mediation could be possible as ANP secretion was blocked by an opioid receptor antagonist (naloxone).


Asunto(s)
Factor Natriurético Atrial/metabolismo , Fentanilo/farmacología , Animales , Células Cultivadas , Femenino , Microscopía Electrónica , Mitocondrias/ultraestructura , Contracción Miocárdica/efectos de los fármacos , Contracción Miocárdica/fisiología , Miocardio/citología , Miocardio/metabolismo , Miocardio/ultraestructura , Miofibrillas/ultraestructura , Naloxona/farmacología , Embarazo , Radioinmunoensayo , Ratas , Ratas Wistar , Sarcómeros/ultraestructura , Retículo Sarcoplasmático/ultraestructura , Factores de Tiempo
19.
Neuropeptides ; 18(2): 87-91, 1991 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-2017302

RESUMEN

The presence of cholecystokinin (CCK) immunoreactive nerve fibres in the rat ovary and uterine tubes was detected using the peroxidase antiperoxidase (PAP) technique. The antibody used was anti CCK 4562 which reacts with CCK-4, CCK-8, CCK-12 and CCK-33 (Larsson and Rehfeld, 1977). CCK-immunoreactive nerve fibres were found between the interstitial cells of the ovary, along blood vessels, and close to smooth muscle fibres in the ovary and tubal wall. A possible role of CCK-nerves in modulation of the sensitivity of the ovarian components to other humoral and nervous stimuli is discussed. The possible control of CCK over smooth muscle fibres in the ovary and the uterine tube and its role in ovulation is a matter of further studies.


Asunto(s)
Colecistoquinina/análisis , Ovario/citología , Útero/citología , Animales , Femenino , Inmunohistoquímica , Músculo Liso/citología , Músculo Liso/inervación , Fibras Nerviosas/ultraestructura , Ovario/inervación , Ratas , Ratas Endogámicas , Útero/inervación
20.
Exp Mol Pathol ; 42(2): 287-92, 1985 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-3920071

RESUMEN

The ultrastructural localization of gold in the ovary of rats injected intraperitoneally with sodium aurothiomalate has been demonstrated using a histochemical technique that visualizes minute traces of gold. Gold was visualized in the oocyte within the cortical granules and in lysosomes of theca interna cells and interstitial cells.


Asunto(s)
Tiomalato Sódico de Oro/toxicidad , Ovario/metabolismo , Animales , Femenino , Microscopía Electrónica , Oocitos/metabolismo , Oocitos/ultraestructura , Ovario/ultraestructura , Ratas , Ratas Endogámicas , Células Tecales/metabolismo , Células Tecales/ultraestructura
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