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1.
Front Neuroendocrinol ; 47: 109-122, 2017 10.
Artículo en Inglés | MEDLINE | ID: mdl-28736323

RESUMEN

Maternal malnutrition significantly increases offspring risk for both metabolic and neurodevelopmental disorders. Animal models of maternal malnutrition have identified behavioral changes in the adult offspring related to executive function and reward processing. Together, these changes in executive and reward-based behaviors likely contribute to the etiology of both metabolic and neurodevelopmental disorders associated with maternal malnutrition. Concomitant with the behavioral effects, maternal malnutrition alters offspring expression of reward-related molecules and inflammatory signals in brain pathways that control executive function and reward. Neuroimmune pathways and microglial interactions in these specific brain circuits, either in early development or later in adulthood, could directly contribute to the maternal malnutrition-induced behavioral phenotypes. Understanding these mechanisms will help advance treatment strategies for metabolic and neurodevelopmental disorders, especially noninvasive dietary supplementation interventions.


Asunto(s)
Encéfalo/inmunología , Desnutrición/inmunología , Fenómenos Fisiologicos Nutricionales Maternos/fisiología , Efectos Tardíos de la Exposición Prenatal/inmunología , Animales , Conducta Animal/fisiología , Femenino , Lactancia/inmunología , Embarazo
2.
J Fish Biol ; 84(1): 267-72, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24383811

RESUMEN

A rapid non-destructive alternative to isolate DNA from an individual fish larva is presented, based on the suspension of epithelial cells through vortex forces, and the release of DNA in a heated alkaline solution. DNA from >6056 fish larvae isolated using this protocol has yielded a high PCR amplification success rate (>93%), suggesting its applicability to other taxonomic groups or sources when tissue amount is the limiting factor.


Asunto(s)
ADN/aislamiento & purificación , Peces , Reacción en Cadena de la Polimerasa/métodos , Animales , Células Epiteliales , Larva/genética , Manejo de Especímenes/métodos
3.
New Microbes New Infect ; 47: 100986, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35668841

RESUMEN

The safety and efficacy of tafenoquine administered as a 200 mg dose once per day on days 1, 2, 3, and 10 was evaluated over a 28-day period in mild-moderate COVID-19 patients. The primary endpoint was Day 14 clinical recovery from COVID-19 symptoms, defined as cough mild or absent, respiratory rate < 24 bpm, and no shortness of breath or fever. Following a successful futility analysis after n = 86 patients out of a target n = 275 were randomized, the study was terminated and unblinded early to facilitate planning for confirmatory studies. The proportion of patients not recovered on Day 14 was numerically decreased by 27% in the ITT population [8/45 v 10/42 not recovered in the tafenoquine and placebo arms, P = 0.60] and 47% in the PP population [5/42 v 9/41, P = 0.25]. Amongst individuals who recorded responses in an electronic diary at Day 28, all tafenoquine patients were recovered, whereas up to 12% of placebo patients exhibited lingering dyspnea. Time to clinical recovery from COVID-19 symptoms was accelerated in the tafenoquine arm by about 2-2.5 days. There were two COVID-19 related hospitalizations in the placebo arm and one in the tafenoquine arm. Mild, drug related adverse events occurred in 8.4% of individuals in the tafenoquine arm [v 2.4% in the placebo]. Although this trial was underpowered for the primary endpoint due to its early termination, the data are suggestive of a therapeutic benefit associated with tafenoquine administration in outpatients with mild to moderate COVID-19 disease, and larger studies are planned.

4.
Ann Surg Oncol ; 18(3): 733-7, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20882415

RESUMEN

BACKGROUND: Neoadjuvant chemotherapy is being increasingly used in operable breast cancer. There are limited data on the safety of bevacizumab (bev) in the neoadjuvant setting. We sought to explore the safety of neoadjuvant cisplatin/bev in a protocol for triple negative breast cancer (TNBC). MATERIALS AND METHODS: A total of 51 patients with confirmed TNBC were enrolled in a single-arm trial of neoadjuvant cisplatin plus bev. Of the 51 patients, 28 with confirmed TNBC were enrolled in our trial of single-agent neoadjuvant cisplatin. Two-sided Fisher exact test were used for comparing the 2 trials. RESULTS: The 51 patients received neoadjuvant protocol therapy with cisplatin/bev and underwent definitive local therapy. Breast conserving therapy (BCT) was performed in 29 (57%) and mastectomy with or without reconstruction in 22 (43%). Postoperative complications were reported in 22 patients (43%); 4 (8%) required explanation of expanders. Also, 28 patients completed neoadjuvant cisplatin therapy. BCT was performed in 13 (46%) and mastectomy with or without reconstruction in 15 (54%). Postoperative complications were reported in 11 patients (39%). None of the 5 reconstructions were lost. We compared all toxicities between the two trials (P = .81 NS), and wound healing related complications between the two trials (P = .10 NS). CONCLUSIONS: Cisplatin/bevacizumab and cisplatin alone neoadjuvant therapy resulted in a significant number of postoperative complications. Specifically, use of expanders/implants may be problematic for patients treated with bev. However, this was a single-arm trial; randomized controlled studies will be needed to determine the optimal use of bevacizumab in the timing of breast cancer surgery.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/cirugía , Terapia Neoadyuvante , Complicaciones Posoperatorias , Adulto , Anciano , Anticuerpos Monoclonales/administración & dosificación , Anticuerpos Monoclonales Humanizados , Bevacizumab , Neoplasias de la Mama/patología , Quimioterapia Adyuvante , Cisplatino/administración & dosificación , Terapia Combinada , Femenino , Humanos , Persona de Mediana Edad , Recurrencia Local de Neoplasia/tratamiento farmacológico , Recurrencia Local de Neoplasia/patología , Recurrencia Local de Neoplasia/cirugía , Estadificación de Neoplasias , Receptor ErbB-2/metabolismo , Receptores de Estrógenos/metabolismo , Receptores de Progesterona/metabolismo , Biopsia del Ganglio Linfático Centinela , Tasa de Supervivencia , Resultado del Tratamiento
5.
J Dairy Sci ; 94(4): 1961-6, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21426987

RESUMEN

The nutritional equivalency of grain plus whole plant silage from genetically modified corn plants containing the DAS-59122-7 (59122) event expressing the Cry34Ab1 and Cry35Ab1 proteins to grain and silage from a near-isogenic corn hybrid without this trait (control) was assessed using lactating dairy cows. Corn plants with event 59122 are resistant to western corn rootworm and tolerant to the herbicide active ingredient glufosinate-ammonium. Effects on feed intake, milk production, and milk composition were determined. The 59122 grain and the control grain were produced in 2005 from isolated plots in Richland, Iowa. Whole plant corn silage for the 59122 and control treatments were grown in isolated plots at the Kansas State University Dairy Center and ensiled in Ag-Bags. Thirty lactating Holstein cows blocked by lactation number, day of lactation, and previous energy-corrected milk production were used in a switchback design. All cows were fed diets that contained 22.7% grain plus 21.3% whole plant silage from either the 59122 or the control hybrid, in addition to 21% wet corn gluten feed, 12.3% protein mix, 8.0% whole cottonseed, and 14.7% alfalfa hay. Each period of the switchback trial included 2 wk for diet adjustment followed by 4 wk for data and sample collection. Milk samples (a.m. and p.m.) collected from 2 consecutive milkings of each collection wk were analyzed for fat, protein, lactose, solids-not-fat, milk urea nitrogen, and somatic cell count. Percentages of milk fat, protein, lactose, and solids-not-fat were not affected by dietary treatment. Yields of milk, 4% fat-corrected milk, energy-corrected milk, solids-corrected milk, and the concentrations and yields of milk fat, milk protein, milk solids, and milk lactose were not significantly different between treatments. Efficiencies of milk, fat-corrected milk, energy-corrected milk, and solids-corrected milk production also were not different when cows were fed crops from 59122 than when they were fed the control hybrid. Milk production efficiency averaged 1.48 and 1.50 kg/kg of dry matter intake for cows fed diets containing the control and 59122 corn, respectively. These data indicate that the nutritional value for milk production was not different between a diet containing grain plus whole plant corn silage produced from a 59122 corn hybrid versus a diet containing grain and corn silage from its near-isogenic control corn hybrid.


Asunto(s)
Bovinos/fisiología , Dieta/veterinaria , Lactancia/fisiología , Plantas Modificadas Genéticamente/genética , Zea mays , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , ADN de Plantas/análisis , Grano Comestible , Femenino , Ensilaje , Zea mays/genética
6.
Br J Surg ; 97(3): 305-16, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20101646

RESUMEN

BACKGROUND: Although effective local control is the primary goal of surgery for breast cancer, the long-term aesthetic outcome is also important. Nipple-sparing mastectomy aims to address this, but there is no consensus on its clinical application. Evidence relating to oncological safety, surgical technique and early data on aesthetic outcome was reviewed. METHODS: The review was based on a PubMed search using the terms 'nipple-sparing' or 'subcutaneous mastectomy' and 'breast cancer'. RESULTS: Large pathological studies report occult nipple involvement with cancer in 5.6-31 per cent, reflecting variation in inclusion criteria. Recent clinical series with careful patient selection report local recurrence in less than 5 per cent of patients. The incidence of cancer in the retained nipple after risk-reducing mastectomy is less than 1 per cent. Nipple necrosis rates range up to 8 and 16 per cent for total and partial necrosis respectively. Variations in outcome result from differences in extent of resection, placement of incisions and type of breast reconstruction. CONCLUSION: Nipple-sparing mastectomy is an acceptable technique for women undergoing risk-reducing mastectomy. In the therapeutic setting, it may be offered to patients with smaller tumours far from the nipple and favourable pathological features. Women should be counselled about nipple necrosis and the potential for local recurrence.


Asunto(s)
Neoplasias de la Mama/cirugía , Mastectomía/métodos , Pezones/cirugía , Femenino , Humanos , Cuidados Intraoperatorios , Necrosis , Pezones/patología , Satisfacción del Paciente , Selección de Paciente , Medición de Riesgo , Sensación , Resultado del Tratamiento
7.
Clin Radiol ; 65(6): 453-9, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20451012

RESUMEN

AIM: To retrospectively assess the frequency of internal mammary lymph nodes (IMNs) in patients after mastectomy and tissue-expander reconstruction. MATERIALS AND METHODS: Statistical analysis was performed for all available data in patients with mastectomy and tissue-expander reconstruction from 2004-2007 (study group). The data were compared with that of a control population with mastectomy who did not have reconstruction (control group). Patients with recurrent breast cancers, previous breast reconstruction, surgeries performed at outside hospitals, no available pre- or postoperative computed tomography (CT) or magnetic resonance imaging (MRI) data, or inadequate imaging follow-up were excluded. RESULTS: There were eight patients in the study group (median age 50.5 years, seven breast cancers), and eight patients in the control group (median age 52 years, seven breast cancers). No patients had IMNs on their preoperative imaging examinations. New IMNs were present in postoperative imaging in seven of eight patients (7/8, 87.5%) in the study group. All of them were stable or decreased in size on subsequent imaging examinations. None of the patients in the control group had IMNs (0/8). CONCLUSION: IMNs are common on imaging after mastectomy and tissue-expander placement. The IMNs decreased or remained stable on follow-up imaging and may represent reactive nodes.


Asunto(s)
Neoplasias de la Mama/diagnóstico por imagen , Ganglios Linfáticos/diagnóstico por imagen , Mamoplastia/métodos , Mastectomía/métodos , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/patología , Neoplasias de la Mama/cirugía , Estudios de Casos y Controles , Femenino , Humanos , Ganglios Linfáticos/patología , Ganglios Linfáticos/cirugía , Metástasis Linfática , Espectroscopía de Resonancia Magnética , Arterias Mamarias , Persona de Mediana Edad , Estudios Retrospectivos , Dispositivos de Expansión Tisular , Tomografía Computarizada por Rayos X
8.
J Cell Biol ; 124(5): 717-27, 1994 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8120094

RESUMEN

We observed that phorbol myristate acetate (PMA) stimulates transcytosis of the polymeric immunoglobulin receptor (pIgR) in MDCK cells. Apical release of pre-endocytosed ligand (dimeric IgA) bound to the pIgR can be stimulated twofold within 7 min of addition of PMA while recycling of the ligand from the basal surface is not affected. In addition, apical surface delivery of pIgR and cleavage of its ectodomain to secretory component (SC) is also stimulated by PMA. The recycling of apically internalized ligand back to the apical surface is similarly stimulated. These results suggest that the stimulation of apical delivery is from an apical recycling compartment. The effect of PMA suggests that protein kinase C (PKC) is involved in the regulation of pIgR trafficking in MDCK cells. To test this we down regulated PKC activity by pre-treating cells with PMA for 16 h and observed that transcytosis could no longer be stimulated by PMA. Western blots show that the PKC isozymes alpha and to a lesser extent epsilon, are depleted from MDCK cells which have been pre-treated with PMA for 16 h and that treatment of MDCK cells with PMA for 5 min causes a dramatic translocation of the PKC alpha isozyme and a partial translocation of the epsilon isozyme from the cytosol to the membrane fraction of cell homogenates. This translocation suggests that the alpha and/or epsilon isozymes may be involved in PMA mediated stimulation of transcytosis. A mutant pIgR in which serines 664 and 726, the major sites of phosphorylation, are replaced by alanine is stimulated to transcytose by PMA, suggesting that phosphorylation of pIgR at these sites is not required for the effect of PMA. These results suggest that PMA-mediated stimulation of pIgR transcytosis may involve the activation of PKC alpha and/or epsilon, and that this stimulation occurs independently of the major phosphorylation sites on the pIgR. Finally, PMA stimulates transcytosis of basolaterally internalized transferrin, suggesting that PMA acts to generally stimulate delivery of endocytosed proteins to the apical surface.


Asunto(s)
Membrana Celular/metabolismo , Endocitosis/efectos de los fármacos , Exocitosis/efectos de los fármacos , Receptores Inmunológicos/metabolismo , Acetato de Tetradecanoilforbol/farmacología , Animales , Western Blotting , Línea Celular , Perros , Isoenzimas/aislamiento & purificación , Isoenzimas/metabolismo , Riñón , Cinética , Proteína Quinasa C/aislamiento & purificación , Proteína Quinasa C/metabolismo , Factores de Tiempo
9.
J Cell Biol ; 120(2): 371-83, 1993 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-7678419

RESUMEN

The sites of water transport along the nephron are well characterized, but the molecular basis of renal water transport remains poorly understood. CHIP28 is a 28-kD integral protein which was proposed to mediate transmembrane water movement in red cells and kidney (Preston, G. M., T. P. Carroll, W. B. Guggino, and P. Agre. 1992. Science [Wash. DC]. 256:385-387). To determine whether CHIP28 could account for renal epithelial water transport, we used specific polyclonal antibodies to quantitate and localize CHIP28 at cellular and subcellular levels in rat kidney using light and electron microscopy. CHIP28 comprised 3.8% of isolated proximal tubule brush border protein. Except for the first few cells of the S1 segment, CHIP28 was immunolocalized throughout the convoluted and straight proximal tubules where it was observed in the microvilli of the apical brush border and in basolateral membranes. Very little CHIP28 was detected in endocytic vesicles or other intracellular structures in proximal tubules. Uninterrupted, heavy immunostaining of CHIP28 was also observed over both apical and basolateral membranes of descending thin limbs, including both short and long loops of Henle. These nephron sites have constitutively high osmotic water permeabilities. CHIP28 was not detected in ascending thin limbs, thick ascending limbs, or distal tubules, which are highly impermeable to water. Moreover, CHIP28 was not detected in collecting duct epithelia, where water permeability is regulated by antidiuretic hormone. These determinations of abundance and structural organization provide evidence that the CHIP28 water channel is the predominant pathway for constitutive transepithelial water transport in the proximal tubule and descending limb of Henle's loop.


Asunto(s)
Acuaporinas , Agua Corporal/metabolismo , Membrana Celular/ultraestructura , Canales Iónicos/ultraestructura , Túbulos Renales Proximales/ultraestructura , Proteínas de la Membrana/análisis , Nefronas/ultraestructura , Animales , Acuaporina 1 , Antígenos de Grupos Sanguíneos , Epitelio/ultraestructura , Membrana Eritrocítica/ultraestructura , Humanos , Immunoblotting , Microscopía Electrónica , Microvellosidades/ultraestructura , Permeabilidad , Ratas
10.
J Cell Biol ; 133(5): 997-1005, 1996 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8655590

RESUMEN

Many membrane traffic events that were previously thought to be constitutive recently have been found to be regulated by a variety of intracellular signaling pathways. The polymeric immunoglobulin receptor (pIgR) transcytoses dimeric IgA (dIgA) from the basolateral to the apical surface of polarized epithelial cells. Transcytosis is stimulated by binding of dIgA to the pIgR, indicating that the pIgR can transduce a signal to the cytoplasmic machinery responsible for membrane traffic. We report that dIgA binding to the pIgR causes activation of protein kinase C (PKC) and release of inositol 1,4,5-trisphosphate (IP3). The IP3 causes an elevation of intracellular Ca. Artificially activating PKC with phorbol myristate acetate or poisoning the calcium pump with thapsigargin stimulates transcytosis of pIgR, while the intracellular Ca chelator BAPTA-AM inhibits transcytosis. Our data suggest that ligand-induced signaling by the pIgR may regulate membrane traffic via well-known second messenger pathways involving PKC, IP3, and Ca. This may be a model of a general means by which membrane traffic is regulated by receptor-ligand interaction and signaling pathways.


Asunto(s)
Receptores de Inmunoglobulina Polimérica/metabolismo , Animales , Calcio/metabolismo , ATPasas Transportadoras de Calcio/antagonistas & inhibidores , ATPasas Transportadoras de Calcio/metabolismo , Línea Celular , Quelantes/farmacología , Perros , Ácido Egtácico/análogos & derivados , Ácido Egtácico/farmacología , Activación Enzimática/efectos de los fármacos , Inhibidores Enzimáticos/farmacología , Exocitosis/efectos de los fármacos , Inmunoglobulina A/metabolismo , Inositol 1,4,5-Trifosfato/biosíntesis , Microtúbulos/metabolismo , Modelos Biológicos , Proteína Quinasa C/metabolismo , Transducción de Señal , Terpenos/farmacología , Acetato de Tetradecanoilforbol/farmacología , Tapsigargina
11.
Science ; 265(5178): 1585-7, 1994 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-7521540

RESUMEN

The gene aquaporin-1 encodes channel-forming integral protein (CHIP), a member of a large family of water transporters found throughout nature. Three rare individuals were identified who do not express CHIP-associated Colton blood group antigens and whose red cells exhibit low osmotic water permeabilities. Genomic DNA analyses demonstrated that two individuals were homozygous for different nonsense mutations (exon deletion or frameshift), and the third had a missense mutation encoding a nonfunctioning CHIP molecule. Surprisingly, none of the three suffers any apparent clinical consequence, which raises questions about the physiological importance of CHIP and implies that other mechanisms may compensate for its absence.


Asunto(s)
Acuaporinas , Canales Iónicos/genética , Animales , Acuaporina 1 , Secuencia de Bases , Antígenos de Grupos Sanguíneos , Permeabilidad de la Membrana Celular , Membrana Eritrocítica/química , Membrana Eritrocítica/fisiología , Exones , Femenino , Homocigoto , Humanos , Canales Iónicos/sangre , Canales Iónicos/orina , Túbulos Renales/química , Datos de Secuencia Molecular , Mutación , Oocitos , Fenotipo , Reacción en Cadena de la Polimerasa , Xenopus
12.
Science ; 292(5523): 1888-92, 2001 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-11397939

RESUMEN

All Australian land mammals, reptiles, and birds weighing more than 100 kilograms, and six of the seven genera with a body mass of 45 to 100 kilograms, perished in the late Quaternary. The timing and causes of these extinctions remain uncertain. We report burial ages for megafauna from 28 sites and infer extinction across the continent around 46,400 years ago (95% confidence interval, 51,200 to 39,800 years ago). Our results rule out extreme aridity at the Last Glacial Maximum as the cause of extinction, but not other climatic impacts; a "blitzkrieg" model of human-induced extinction; or an extended period of anthropogenic ecosystem disruption.


Asunto(s)
Aves , Fósiles , Mamíferos , Reptiles , Animales , Australia , Constitución Corporal , Clima , Ecosistema , Sedimentos Geológicos , Humanos , Óptica y Fotónica , Torio , Tiempo , Uranio
13.
Ann Surg Oncol ; 15(12): 3384-95, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18726129

RESUMEN

BACKGROUND: Reports demonstrate improved survival of stage IV breast cancer patients with primary cancer resection. This may result from selection for surgery, rather than biological processes. METHODS: We performed matched-pair analysis that minimized potential bias in selecting surgery for primary cancer. Chart review was also performed of 5-year survivors to assess selection bias affecting breast surgery. RESULTS: 19,464 breast cancer patients were identified; 808 (4.2%) were stage IV: 622 were analyzed after eliminating wrong diagnoses or staging, and limiting patients to Massachusetts residents. Matched-pair analysis narrowed or eliminated apparent survival benefit associated with primary site surgery in several comparisons. When the impact of the sequence of systemic and surgical treatments was studied in stage IV patients, 90% 2-year survival occurred in patients receiving chemotherapy first, in contrast to receiving chemotherapy simultaneously with or after surgery, suggesting selection for delayed surgery after excellent response to initial chemotherapy. In bone metastases, the 2-year survival advantage occurred with chemotherapy before surgery; no difference in survival with or without surgery occurred when these treatments were simultaneous. Among 5-year survivors, frequency of primary site surgery after excellent response to systemic therapy, breast surgery in stage III patients incorrectly classified as stage IV, and frequency of oligo metastases all indicated selection bias. CONCLUSIONS: Case selection bias in primary breast cancer resection in state IV patients may explain most, if not all, the apparent survival advantage of such surgery.


Asunto(s)
Neoplasias de la Mama/patología , Neoplasias de la Mama/cirugía , Mastectomía/estadística & datos numéricos , Análisis por Apareamiento , Biopsia del Ganglio Linfático Centinela , Neoplasias de la Mama/secundario , Femenino , Estudios de Seguimiento , Humanos , Metástasis Linfática , Massachusetts , Persona de Mediana Edad , Estadificación de Neoplasias , Pronóstico , Sesgo de Selección , Tasa de Supervivencia , Factores de Tiempo , Resultado del Tratamiento
14.
Br J Surg ; 95(11): 1356-61, 2008 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-18844271

RESUMEN

BACKGROUND: This prospective study aimed to build a predictive model using preoperative information to aid selection for nipple-sparing mastectomy. METHODS: Two hundred consecutive skin-sparing mastectomy specimens without overt nipple involvement were evaluated. Demographic, preoperative pathology and imaging information was collected. Nipple specimens (2 x 2 x 2 cm) were sectioned at 3-mm intervals. Haematoxylin and eosin-stained slides were examined by a breast pathologist for involvement by tumour. Logistic regression analyses of 65 therapeutic procedures identified factors associated with occult involvement and created a predictive model. This was tested on specimens from a further 65 therapeutic procedures. RESULTS: Occult nipple involvement was noted in 32 (24.6 per cent) of 130 mastectomy specimens. In the training set, imaging diameter of the lesion and its distance from the nipple predicted nipple involvement on univariable analysis (P = 0.011 and P = 0.014 respectively). The multivariable logistic regression model was validated in the test set. The areas under the receiver-operating characteristic curve were 0.824 and 0.709 for the training and test sets respectively. CONCLUSION: Three-quarters of women undergoing mastectomy did not have occult nipple involvement. A clinical tool including tumour size and distance from the nipple has been developed to improve patient selection for nipple-sparing mastectomy.


Asunto(s)
Neoplasias de la Mama/patología , Mastectomía Subcutánea/métodos , Pezones/patología , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias de la Mama/cirugía , Femenino , Humanos , Persona de Mediana Edad , Pezones/cirugía , Selección de Paciente , Estudios Prospectivos , Análisis de Regresión
15.
J Clin Invest ; 95(1): 422-8, 1995 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-7529263

RESUMEN

Several transporters have been localized along the nephron by physiological methods or immunocytochemistry. However, the actual abundance of these molecules has not been established. To accomplish this goal, we have developed a fluorescence-based ELISA method and have used it to quantitate Aquaporin-CHIP (AQP-CHIP) water channel protein in rat kidney tubules. Microdissected tubules (2 mm/sample, permeabilized with 0.5% Triton X-100) or purified AQP-CHIP standards (0-200 fmol) were utilized in a fluorescence ELISA protocol after covalent immobilization on epoxy-activated Sepharose beads. The lower limit of detection was 2.4 fmol of AQP-CHIP. Preabsorption with excess purified AQP-CHIP or use of nonimmune serum eliminated the signal. In proximal segments, the measured AQP-CHIP was linearly related to tubule length (1-10 mm). The measured AQP-CHIP was (mean +/- SE, fmol/mm): S-1 proximal, 10.8 +/- 2.1; S-2, 10.0 +/- 2.3; S-3, 21.3 +/- 3.1; type 1 thin descending limb (DTL), 12.9 +/- 4.6; type 2 DTL, 86.5 +/- 19.5; type 3 DTL, 43.0 +/- 11.2. In thin ascending limbs, thick ascending limbs, distal convoluted tubules, connecting tubules, and collecting ducts, the AQP-CHIP signal was indistinguishable from zero. Based on the unit water conductance of single CHIP molecules, our calculations show that the content of AQP-CHIP is sufficient to explain water permeability measured in isolated proximal tubules and DTL segments.


Asunto(s)
Acuaporinas , Ensayo de Inmunoadsorción Enzimática/métodos , Canales Iónicos/aislamiento & purificación , Túbulos Renales/química , Animales , Acuaporina 1 , Disección , Fluorescencia , Canales Iónicos/normas , Túbulos Renales Colectores/química , Nefronas/química , Octoxinol/farmacología , Ratas , Ratas Sprague-Dawley , Sensibilidad y Especificidad , Distribución Tisular
16.
J Clin Invest ; 92(4): 2035-41, 1993 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8408657

RESUMEN

Major phenotypic changes occur in red cell membranes during the perinatal period, but the underlying molecular explanations remain poorly defined. Aquaporin CHIP, the major erythroid and renal water channel, was studied in perinatal rats using affinity-purified anti-CHIP IgG for immunoblotting, flow cytometry, and immunofluorescence microscopy. CHIP was not detected in prenatal red cells but was first identified in circulating red cells on the third postnatal day. Most circulating red cells were positive for CHIP by the seventh postnatal day, and this proportion rose to nearly 100% by the 14th day. The ontogeny of red cell CHIP correlated directly with acquisition of osmotic water permeability and inversely with Arrhenius activation energy. Only minor alterations in the composition of red cell membrane lipids occurred at this time. Immunohistochemical analysis of perinatal kidneys demonstrated a major induction of CHIP in renal proximal tubules and descending thin limbs at birth, coincident with the development of renal concentration mechanisms. Therefore, water channels are unnecessary for oxygen delivery or survival in the prenatal circulation, however CHIP may confer red cells with the ability to rehydrate rapidly after traversing the renal medulla, which becomes hypertonic after birth.


Asunto(s)
Envejecimiento/metabolismo , Acuaporinas , Membrana Eritrocítica/metabolismo , Riñón/metabolismo , Proteínas de la Membrana/biosíntesis , Proteínas de la Membrana/sangre , Animales , Acuaporina 1 , Permeabilidad de la Membrana Celular , Desarrollo Embrionario y Fetal/fisiología , Membrana Eritrocítica/ultraestructura , Femenino , Sangre Fetal , Técnica del Anticuerpo Fluorescente , Immunoblotting , Riñón/embriología , Riñón/crecimiento & desarrollo , Corteza Renal/metabolismo , Médula Renal/metabolismo , Lípidos de la Membrana/sangre , Proteínas de la Membrana/aislamiento & purificación , Fosfolípidos/sangre , Embarazo , Ratas , Ratas Sprague-Dawley
17.
J Clin Invest ; 94(3): 1043-9, 1994 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-7521882

RESUMEN

Blood group antigens are structural variants in surface carbohydrate or amino acid polymorphisms on extracellular domains of membrane proteins. The red cell water channel-forming integral protein (Aquaporin CHIP) is a homotetramer with only one N-glycosylated subunit, however no CHIP-associated blood group antigens have yet been identified. Immunoblotting, monosaccharide composition analysis, and selective glycosidase digestions revealed that the CHIP-associated oligosaccharide contains ABH determinants and resembles a band 3-type glycan that cannot be cleaved from intact membranes by Peptide:N-glycosidase F. The molecular structure of the Colton antigens was previously unknown, but CHIP was selectively immunoprecipitated with anti-Coa or anti-Co(b). The DNA sequence from Colton-typed individuals predicted that residue 45 is alanine in the Co(a+b-) phenotype and valine in the Co(a-b+) phenotype. The nucleotide polymorphism corresponds to a PflMI endonuclease digestion site in the DNA from Co(a-b+) individuals. These studies have defined antigens within two blood group systems on CHIP: (a) an ABH-bearing polylactosaminoglycan attached to a poorly accessible site in the native membrane; and (b) the Colton antigen polymorphism which may permit the identification of rare individuals with defective water channel expression.


Asunto(s)
Sistema del Grupo Sanguíneo ABO/química , Acuaporinas , Membrana Eritrocítica/química , Canales Iónicos/sangre , Canales Iónicos/química , Oligosacáridos/química , Sistema del Grupo Sanguíneo ABO/sangre , Acuaporina 1 , Secuencia de Bases , Antígenos de Grupos Sanguíneos , Conformación de Carbohidratos , Secuencia de Carbohidratos , Línea Celular , Cartilla de ADN , Exones , Humanos , Canales Iónicos/genética , Linfocitos/metabolismo , Sustancias Macromoleculares , Datos de Secuencia Molecular , Monosacáridos/análisis , Fenotipo , Reacción en Cadena de la Polimerasa , Polimorfismo Genético , Estructura Secundaria de Proteína , Mapeo Restrictivo
18.
J Clin Invest ; 94(3): 1050-8, 1994 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-7521883

RESUMEN

Channel-forming integral protein (CHIP) is the archetypal member of the Aquaporin family of water channels. Delayed CHIP expression was shown recently in perinatal rat (Smith, B. L., R. Baumgarten, S. Nielsen, D. Raben, M. L. Zeidel, and P. Agre. 1993. J. Clin. Invest. 92:2035-2041); here we delineate the human patterns. Compared with adult, second and third trimester human fetal red cells had lower CHIP/spectrin ratios (0.72 +/- 0.12, 0.94 +/- 0.22 vs 1.18 +/- 0.11) and reduced osmotic water permeability (0.029, 0.026 vs 0.037 cm/s); CHIP was already present in human renal tubules by the second trimester. A patient with a novel form of congenital dyserythropoietic anemia (CDA) with persistent embryonic and fetal globins and absent red cell CD44 protein was studied because of reduced CHIP-associated Colton antigens. Novel CDA red cells contained < 10% of the normal level of CHIP and had remarkably low osmotic water permeability (< 0.01 cm/s), but no mutation was identified in Aquaporin-1, the gene encoding CHIP. These studies demonstrate: (a) unlike rat, human CHIP expression occurs early in fetal development; (b) red cell water channels are greatly reduced in a rare phenotype; and (c) disrupted expression of red cell CHIP and CD44 suggests an approach to the molecular defect in a novel form of CDA.


Asunto(s)
Anemia Diseritropoyética Congénita/sangre , Acuaporinas , Desarrollo Embrionario y Fetal , Eritrocitos/fisiología , Canales Iónicos/biosíntesis , Riñón/metabolismo , Adulto , Anemia Diseritropoyética Congénita/genética , Animales , Acuaporina 1 , Antígenos de Grupos Sanguíneos , Proteínas Portadoras/biosíntesis , Proteínas Portadoras/sangre , Niño , Femenino , Sangre Fetal , Feto , Edad Gestacional , Humanos , Receptores de Hialuranos , Inmunohistoquímica , Lactante , Canales Iónicos/análisis , Canales Iónicos/sangre , Riñón/embriología , Mutación , Fragilidad Osmótica , Permeabilidad , Fenotipo , Embarazo , Ratas , Receptores de Superficie Celular/biosíntesis , Receptores Mensajeros de Linfocitos/biosíntesis , Valores de Referencia , Espectrina/análisis
19.
Cancer Res ; 42(2): 389-96, 1982 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-6799186

RESUMEN

Twenty-one anchorage-independent subclones and ten subclones with reduced serum requirements were isolated as single-step mutants spontaneously or after ethylmethanesulfonate or N-methyl-N'-nitro-N-nitrosoguanidine mutagenesis of CHEF/18 diploid Chinese hamster embryo fibroblasts. Anchorage-independent mutants retain the high serum requirement and nontransformed morphology typical of CHEF/18. Only four of 21 anchorage mutants have spontaneously produced tumors when injected at 10(7)/site in nude mice, and these were only at a fraction of sites. Low-serum (LS) mutants acquire transformed morphology and increased anchorage-independent growth simultaneously with the loss of high-serum requirement. Only two of ten LS mutants have spontaneously produced tumors. However, when some anchorage and LS mutants were remutagenized and when mutagenized populations were injected into nude mice, tumors appeared at many of the injected sites. In contrast, untreated CHEF/18 cells have never given tumors(0 of 34 sites), and mutagenized DHEF/18 cells have given tumors at only three of 29 sites. These results demonstrate that malignant transformation is a multistep process in the Chinese hamster embryo fibroblast system. Most one-step mutants selected for anchorage independence or reduced serum requirements do not have tumor-forming potentials higher than that of the parent CHEF/18. Thus anchorage-independent and LS phenotypes per se do not account for the increase in tumor-forming potential. It is proposed that the genomic rearrangement process as well as specific mutations may contribute to tumorigenicity.


Asunto(s)
Transformación Celular Neoplásica/inducido químicamente , Neoplasias Experimentales/etiología , 4-Nitroquinolina-1-Óxido/farmacología , Animales , Línea Celular , Transformación Celular Neoplásica/patología , Cricetinae , Cricetulus , Medios de Cultivo , Embrión de Mamíferos , Metanosulfonato de Etilo/toxicidad , Metilnitronitrosoguanidina/farmacología , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Mutación , Fenotipo , Irradiación Corporal Total
20.
Prog Biophys Mol Biol ; 74(1-2): 93-113, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11106808

RESUMEN

Molecular structure holds a key to understanding Nature's intricate design mechanisms and blueprints. If we can understand her blueprints and basic materials, perhaps we can begin to mimic her beautiful products more cost effectively and with less detrimental environmental consequences. Higher resolution instrumentation has allowed us to study single molecules. Indeed, many stellar contributions to the field have come forth in the last couple of years. We can measure the forces required to unravel individual domains of biological molecules such as titin or DNA to a few picoNewtons resolution. This review will attempt to provide a general overview of the field of single molecule analysis using scanning force microscopy.


Asunto(s)
Microscopía de Sonda de Barrido/instrumentación , Conformación Molecular , Adhesivos/química , Animales , Carbonato de Calcio/química , ARN Polimerasas Dirigidas por ADN/química , Proteínas de Insectos/química , Moluscos/química , Ácidos Nucleicos/química , Seda
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