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1.
Phys Rev Lett ; 130(18): 183602, 2023 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-37204878

RESUMEN

The Heisenberg limit to laser coherence C-the number of photons in the maximally populated mode of the laser beam-is the fourth power of the number of excitations inside the laser. We generalize the previous proof of this upper bound scaling by dropping the requirement that the beam photon statistics be Poissonian (i.e., Mandel's Q=0). We then show that the relation between C and sub-Poissonianity (Q<0) is win-win, not a tradeoff. For both regular (non-Markovian) pumping with semiunitary gain (which allows Q→-1), and random (Markovian) pumping with optimized gain, C is maximized when Q is minimized.

2.
BMC Neurol ; 21(1): 355, 2021 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-34521381

RESUMEN

BACKGROUND: Continuous spike and wave of sleep with encephalopathy (CSWS) is a rare and severe developmental electroclinical epileptic encephalopathy characterized by seizures, abundant sleep activated interictal epileptiform discharges, and cognitive regression or deceleration of expected cognitive growth. The cause of the cognitive symptoms is unknown, and efforts to link epileptiform activity to cognitive function have been unrevealing. Converging lines of evidence implicate thalamocortical circuits in these disorders. Sleep spindles are generated and propagated by the same thalamocortical circuits that can generate spikes and, in healthy sleep, support memory consolidation. As such, sleep spindle deficits may provide a physiologically relevant mechanistic biomarker for cognitive dysfunction in epileptic encephalopathies. CASE PRESENTATION: We describe the longitudinal course of a child with CSWS with initial cognitive regression followed by dramatic cognitive improvement after treatment. Using validated automated detection algorithms, we analyzed electroencephalograms for epileptiform discharges and sleep spindles alongside contemporaneous neuropsychological evaluations over the course of the patient's disease. We found that sleep spindles increased dramatically with high-dose diazepam treatment, corresponding with marked improvements in cognitive performance. We also found that the sleep spindle rate was anticorrelated to spike rate, consistent with a competitively shared underlying thalamocortical circuitry. CONCLUSIONS: Epileptic encephalopathies are challenging electroclinical syndromes characterized by combined seizures and a deceleration or regression in cognitive skills over childhood. This report identifies thalamocortical circuit dysfunction in a case of epileptic encephalopathy and motivates future investigations of sleep spindles as a biomarker of cognitive function and a potential therapeutic target in this challenging disease.


Asunto(s)
Encefalopatías , Diazepam , Niño , Cognición , Electroencefalografía , Humanos , Sueño
3.
Gene Ther ; 21(3): 253-61, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24451115

RESUMEN

Primary ciliary dyskinesia (PCD) is a genetically heterogenous autosomal recessive disease in which mutations disrupt ciliary function, leading to impaired mucociliary clearance and life-long lung disease. Mouse tracheal cells with a targeted deletion in the axonemal dynein intermediate chain 1 (Dnaic1) gene differentiate normally in culture but lack ciliary activity. Gene transfer to undifferentiated cultures of mouse Dnaic1(-/-) cells with a lentiviral vector pseudotyped with avian influenza hemagglutinin restored Dnaic1 expression and ciliary activity. Importantly, apical treatment of well-differentiated cultures of mouse Dnaic1(-/-) cells with lentiviral vector also restored ciliary activity, demonstrating successful gene transfer from the apical surface. Treatment of Dnaic1(flox/flox) mice expressing an estrogen-responsive Cre recombinase with different doses of tamoxifen indicated that restoration of ∼20% of ciliary activity may be sufficient to prevent the development of rhinosinusitis. However, although administration of a ß-galactosidase-expressing vector into control mice demonstrated efficient gene transfer to the nasal epithelium, treatment of Dnaic1(-/-) mice resulted in a low level of gene transfer, demonstrating that the severe rhinitis present in these animals impedes gene transfer. The results demonstrate that gene replacement therapy may be a viable treatment option for PCD, but further improvements in the efficiency of gene transfer are necessary.


Asunto(s)
Dineínas Axonemales/metabolismo , Trastornos de la Motilidad Ciliar/terapia , Terapia Genética , Lentivirus/genética , Animales , Dineínas Axonemales/genética , Células Cultivadas , Cilios/metabolismo , Cilios/fisiología , Antagonistas de Estrógenos/farmacología , Vectores Genéticos/genética , Integrasas/genética , Lentivirus/metabolismo , Ratones , Ratones Endogámicos C57BL , Mucosa Respiratoria/efectos de los fármacos , Mucosa Respiratoria/metabolismo , Rinitis/terapia , Sinusitis/terapia , Tamoxifeno/farmacología
4.
Am J Physiol Lung Cell Mol Physiol ; 302(2): L238-47, 2012 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-22003093

RESUMEN

The relationships between airway epithelial Cl(-) secretion-Na(+) absorption balance, airway surface liquid (ASL) homeostasis, and lung disease were investigated in selected transgenic mice. 1) To determine if transgenic overexpression of wild-type (WT) human CFTR (hCFTR) accelerated Cl(-) secretion and regulated Na(+) absorption in murine airways, we utilized a Clara cell secretory protein (CCSP)-specific promoter to generate mice expressing airway-specific hCFTR. Ussing chamber studies revealed significantly (∼2.5-fold) elevated basal Cl(-) secretory currents in CCSP-hCFTR transgenic mouse airways. Endogenous murine airway Na(+) absorption was not regulated by hCFTR, and these mice exhibited no lung disease. 2) We tested whether hCFTR, transgenically expressed on a transgenic mouse background overexpressing the ß-subunit of the epithelial Na(+) channel (ß-ENaC), restored ion transport balance and ASL volume homeostasis and ameliorated lung disease. Both transgenes were active in CCSP-hCFTR/ß-ENaC transgenic mouse airways, which exhibited an elevated basal Cl(-) secretion and Na(+) hyperabsorption. However, the airway disease characteristic of ß-ENaC mice persisted. Confocal studies of ASL volume homeostasis in cultured tracheal cells revealed ASL autoregulation to a height of ∼6 µm in WT and CCSP-hCFTR cultures, whereas ASL was reduced to <4 µm in ß-ENaC and CCSP-hCFTR/ß-ENaC cultures. We conclude that 1) hCFTR overexpression increases basal Cl(-) secretion but does not regulate Na(+) transport in WT mice and 2) transgenic hCFTR produces increased Cl(-) secretion, but not regulation of Na(+) channels, in ß-ENaC mouse airways and does not ameliorate ß-ENaC mouse lung disease.


Asunto(s)
Regulador de Conductancia de Transmembrana de Fibrosis Quística/genética , Regulador de Conductancia de Transmembrana de Fibrosis Quística/metabolismo , Canales Epiteliales de Sodio/metabolismo , Transporte Iónico/genética , Enfermedades Pulmonares/metabolismo , Mucosa Respiratoria/metabolismo , Canales de Sodio/metabolismo , Animales , Células Cultivadas , Cloruros/metabolismo , Canales Epiteliales de Sodio/genética , Genotipo , Pulmón/metabolismo , Enfermedades Pulmonares/genética , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Regiones Promotoras Genéticas , Mucosa Respiratoria/citología , Mucosa Respiratoria/patología , Sistema Respiratorio , Sodio/metabolismo , Canales de Sodio/genética , Tráquea/metabolismo , Uteroglobina/genética
5.
J Mol Med (Berl) ; 99(2): 289-301, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33392634

RESUMEN

Primary brain tumors remain among the deadliest of all cancers. Glioma grade IV (glioblastoma), the most common and malignant type of brain cancer, is associated with a 5-year survival rate of < 5%. Melatonin has been widely reported as an anticancer molecule, and we have recently demonstrated that the ability of gliomas to synthesize and accumulate this indolamine in the surrounding microenvironment negatively correlates with tumor malignancy. However, our understanding of the specific effects mediated through the activation of melatonin membrane receptors remains limited. Thus, here we investigated the specific roles of MT1 and MT2 in gliomas and medulloblastomas. Using the MT2 antagonist DH97, we showed that MT1 activation has a negative impact on the proliferation of human glioma and medulloblastoma cell lines, while MT2 activation has an opposite effect. Accordingly, gliomas have a decreased mRNA expression of MT1 (also known as MTNR1A) and an increased mRNA expression of MT2 (also known as MTNR1B) compared to the normal brain cortex. The MT1/MT2 expression ratio negatively correlates with the expression of cell cycle-related genes and is a positive prognostic factor in gliomas. Notably, we showed that functional selective drugs that simultaneously activate MT1 and inhibit MT2 exert robust anti-tumor effects in vitro and in vivo, downregulating the expression of cell cycle and energy metabolism genes in glioma stem-like cells. Overall, we provided the first evidence regarding the differential roles of MT1 and MT2 in brain tumor progression, highlighting their relevance as druggable targets. KEY MESSAGES: • MT1 impairs while MT2 promotes the proliferation of glioma and medulloblastoma cell lines. • Gliomas have a decreased expression of MT1 and an increased expression of MT2 compared to normal brain cortex. • Tumors with a high MT1/MT2 expression ratio have significantly better survival rates. • Functional selective drugs that simultaneously activate MT1 and inhibit MT2 downregulate the expression of cell cycle and energy metabolism genes in glioma stem-like cells and exert robust anti-tumor effects in vivo.


Asunto(s)
Neoplasias Encefálicas , Glioma , Receptor de Melatonina MT1 , Receptor de Melatonina MT2 , Animales , Encéfalo/metabolismo , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/mortalidad , Neoplasias Encefálicas/patología , Línea Celular Tumoral , Proliferación Celular , Progresión de la Enfermedad , Femenino , Glioma/genética , Glioma/metabolismo , Glioma/mortalidad , Glioma/patología , Humanos , Estimación de Kaplan-Meier , Masculino , Ratones Endogámicos BALB C , Ratones Desnudos , Receptor de Melatonina MT1/genética , Receptor de Melatonina MT1/metabolismo , Receptor de Melatonina MT2/genética , Receptor de Melatonina MT2/metabolismo
6.
J Cell Biol ; 145(6): 1277-92, 1999 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-10366599

RESUMEN

It is well established that mutations in the presenilin 1 and 2 genes cause the majority of early onset Alzheimer's disease (AD). However, our understanding of the cellular functions of the proteins they encode remains rudimentary. Knowledge of proteins with which the presenilins interact should lead to a better understanding of presenilin function in normal and disease states. We report here the identification of a calcium-binding protein, calmyrin, that interacts preferentially with presenilin 2 (PS2). Calmyrin is myristoylated, membrane-associated, and colocalizes with PS2 when the two proteins are overexpressed in HeLa cells. Yeast two-hybrid liquid assays, affinity chromatography, and coimmunoprecipitation experiments confirm binding between PS2 and calmyrin. Functionally, calmyrin and PS2 increase cell death when cotransfected into HeLa cells. These results allude to several provocative possibilities for a dynamic role of calmyrin in signaling, cell death, and AD.


Asunto(s)
Proteínas de Unión al Calcio/metabolismo , Calcio/metabolismo , Lipoproteínas/metabolismo , Proteínas de la Membrana/metabolismo , Ácidos Mirísticos/metabolismo , Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/metabolismo , Secuencia de Aminoácidos , Apoptosis , Proteínas de Unión al Calcio/análisis , Proteínas de Unión al Calcio/química , Proteínas de Unión al Calcio/genética , Núcleo Celular/metabolismo , Cromatografía de Afinidad , Citoplasma/metabolismo , Retículo Endoplásmico/metabolismo , Técnica del Anticuerpo Fluorescente , Expresión Génica , Células HeLa , Humanos , Lipoproteínas/análisis , Lipoproteínas/química , Lipoproteínas/genética , Proteínas de la Membrana/análisis , Proteínas de la Membrana/química , Proteínas de la Membrana/genética , Datos de Secuencia Molecular , Fragmentos de Péptidos/química , Fragmentos de Péptidos/genética , Fragmentos de Péptidos/metabolismo , Pruebas de Precipitina , Presenilina-2 , Unión Proteica , ARN Mensajero/análisis , ARN Mensajero/genética , ARN Mensajero/metabolismo , Transfección , Levaduras/genética , Levaduras/metabolismo
7.
Obes Sci Pract ; 5(1): 46-58, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30847225

RESUMEN

OBJECTIVE: To determine the efficacy of a 4-month school-based health, nutrition and exercise intervention on body fatness and examine possible effects of demographic and anthropometric covariates. METHODS: Height, weight, waist circumference and body composition were measured in a diverse population of 644 NYC middle school students (mean ± SD age 12.7 ± 0.9 years; 46% male; 38% Hispanic, 17% East Asian, 15% South Asian, 13.5% African American, 8.5% Caucasian, 8% other) during the fall and spring semesters. Year 1 participants (n = 322) were controls. Experimental participants (year 2, n = 469) received a 12-session classroom-based health and nutrition educational programme with an optional exercise intervention. RESULTS: Groups were demographically and anthropometrically similar. The intervention resulted in significant reductions in indices of adiposity (ΔBMI z-scores [-0.035 ± 0.014; p = 0.01], Δ% body fat [-0.5 ± 0.2; p < 0.0001] and Δwaist circumference [-0.73 ± 0.30 cm; p < 0.0001]). Intervention effects were greater (p = 0.01) in men (ΔBMI z-score = -0.052 ± 0.015) versus women (0.022 ± 0.018), participants who were obese (ΔBMI z-score -0.083 ± 0.022 kg m-2) versus lean (-0.0097 ± 0.020 kg m-2) and South Asians (Δ% body fat -1.03 ± 0.35) versus total (-0.49 ± 0.20%) participants (p = 0.005). CONCLUSION: A 4-month school-based health intervention was effective in decreasing measures of adiposity in middle school students, particularly in men, participants who were obese and South Asians.

8.
Mol Biol Cell ; 7(1): 71-9, 1996 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8741840

RESUMEN

Axonemal dyneins are molecular motors that drive the beating of cilia and flagella. We report here the identification and partial cloning of seven unique axonemal dynein heavy chains from rat tracheal epithelial (RTE) cells. Combinations of axonemal-specific and degenerate primers to conserved regions around the catalytic site of dynein heavy chains were used to obtain cDNA fragments of rat dynein heavy chains. Southern analysis indicates that these are single copy genes, with one possible exception, and Northern analysis of RNA from RTE cells shows a transcript of approximately 15 kb for each gene. Expression of these genes was restricted to tissues containing axonemes (trachea, testis, and brain). A time course analysis during ciliated cell differentiation of RTE cells in culture demonstrated that the expression of axonemal dynein heavy chains correlated with the development of ciliated cells, while cytoplasmic dynein heavy chain expression remained constant. In addition, factors that regulate the development of ciliated cells in culture regulated the expression of axonemal dynein heavy chains in a parallel fashion. These are the first mammalian dynein heavy chain genes shown to be expressed specifically in axonemal tissues. Identification of the mechanisms that regulate the cell-specific expression of these axonemal dynein heavy chains will further our understanding of the process of ciliated cell differentiation.


Asunto(s)
Diferenciación Celular , Cilios/química , Dineínas/genética , Regulación de la Expresión Génica , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Northern Blotting , Southern Blotting , Células Cultivadas , Clonación Molecular , Células Epiteliales , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa , Ratas , Tráquea
9.
Nanoscale ; 9(15): 4907-4917, 2017 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-28358158

RESUMEN

The solid concentration of pulmonary mucus (wt%) is critical to respiratory health. In patients with respiratory disease, such as Cystic Fibrosis (CF) and Chronic Obstructive Pulmonary Disorder (COPD), mucus hydration is impaired, resulting in high wt%. Mucus with high wt% is a hallmark of pulmonary disease that leads to obstructed airways, inflammation, and infection. Methods to measure mucus hydration in situ and in real-time are needed for drug development and personalized therapy. We employed plasmonic gold nanorod (GNR) biosensors that intermittently collide with macromolecules comprising the mucus mesh as they self-diffuse, such that GNR translational diffusion (DT) is sensitive to wt%. GNRs are attractive candidates for bioprobes due to their anisotropic optical scattering that makes them easily distinguishable from native tissue using polarization-sensitive OCT. Using principles of heterodyne dynamic light scattering, we developed diffusion-sensitive optical coherence tomography (DS-OCT) to spatially-resolve changing DT in real-time. DS-OCT enables, for the first time, direct monitoring of changes in nanoparticle diffusion rates that are sensitive to nanoporosity with spatial and temporal resolutions of 4.7 µm and 0.2 s. DS-OCT therefore enables us to measure spatially-resolved changes in mucus wt% over time. In this study, we demonstrate the applicability of DS-OCT on well-differentiated primary human bronchial epithelial cells during a clinical mucus-hydrating therapy, hypertonic saline treatment (HST), to reveal, for the first time, mucus mixing, cellular secretions, and mucus hydration on the micrometer scale that translate to long-term therapeutic effects.


Asunto(s)
Técnicas Biosensibles , Células Epiteliales/citología , Oro , Moco/química , Nanotubos , Bronquios/citología , Células Cultivadas , Difusión , Humanos , Enfermedades Pulmonares/tratamiento farmacológico , Tomografía de Coherencia Óptica
10.
Cancer Res ; 46(8): 4129-34, 1986 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-3524801

RESUMEN

The ability of B16-F10 mouse melanoma cells to cross an amnion basement membrane was determined in the presence of strong inhibitors of both serine and cysteine proteases. The concentrations of inhibitors were at orders of magnitude higher than their Ki values to serine and cysteine proteases implicated in metastasis, thus ensuring a complete inhibition for tumor secreted proteases such as cathepsin B-like proteases, plasminogen activators, and plasmin. Under these conditions of high serine and cysteine protease inhibitor concentrations, no significant decrease in B16-F10 melanoma cell invasion through the amnion was observed. Separate experiments showed that the inhibitors were neither toxic to the cells nor degraded. The results show that neither tumor cell secreted cathepsin B-like proteases nor plasminogen activator have a controlling role in basement membrane crossing in this metastatic model. A possible role for tumor cell membrane proteases in basement membrane invasion, in which the substrates of the protease bind to receptor sites near a membrane associated proteolytic activity, is not eliminated.


Asunto(s)
Membrana Basal/patología , Invasividad Neoplásica , Inhibidores de Proteasas/farmacología , Amnios/patología , Animales , Fenómenos Fisiológicos Sanguíneos , Catepsina B , Catepsinas/fisiología , Membrana Celular/enzimología , Cisteína Endopeptidasas , Endopeptidasas , Femenino , Humanos , Técnicas In Vitro , Leupeptinas/farmacología , Melanoma/patología , Ratones , Activadores Plasminogénicos/fisiología , Embarazo , Serina Endopeptidasas , Activador de Plasminógeno de Tipo Uroquinasa/antagonistas & inhibidores
11.
Cancer Res ; 51(13): 3339-44, 1991 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-2054774

RESUMEN

Four synthetic peptides from the sequence of human O6-methylguanine-DNA methyltransferase (MGMT), three corresponding to different hydrophilic regions and one corresponding to the sequence containing the alkyl acceptor residue cysteine 145, were used to immunize rabbits. The antibody against Peptide III (residues 171-184) was highly specific, and MGMT protein could be detected on Western blots of soluble protein extracts containing as little as 1 fmol of active MGMT. Antibodies against all of the peptides were able to immunoprecipitate denatured MGMT, while only the antibody against Peptide III was able to react with active enzyme. The antibody against Peptide III did not cross-react with methyltransferase from mice. The use of synthetic peptides has led to the production of a highly sensitive, specific antibody that recognizes native and denatured human MGMT. This antibody should prove useful in studies involving the detection, purification, and characterization of this enzyme.


Asunto(s)
Anticuerpos/inmunología , Metiltransferasas/inmunología , Secuencia de Aminoácidos , Especificidad de Anticuerpos , Western Blotting , Humanos , Metiltransferasas/química , Datos de Secuencia Molecular , O(6)-Metilguanina-ADN Metiltransferasa , Péptidos/síntesis química , Péptidos/inmunología , Pruebas de Precipitina , Solubilidad , Especificidad de la Especie
12.
Cancer Res ; 46(8): 4121-8, 1986 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-3089587

RESUMEN

Peptide aldehyde transition state analogue inhibitors of serine and cysteine proteases have been used to selectively inhibit proteases for which prior evidence supports a role in tumor cell metastasis. These enzymes include cathepsin B, urokinase plasminogen activator (PA), and thrombin. The inhibition constants of the peptidyl aldehyde inhibitors show that they are highly selective for a particular targeted serine or cysteine protease. The inhibitors are introduced by i.p. injection or by miniosmotic pumps into syngeneic C57BL/6 mice also given injections of B16-F10 melanoma cells, and the number of metastatic foci in the lung was determined. While the injection protocol gave an initially high but changing in vivo concentration of inhibitor over time, the minipump implant gave a constant steady state concentration of inhibitor over 5-7 days. Minipump infusion of leupeptin (acetylleucylleucylargininal), a strong inhibitor of cathepsin B at a steady state plasma concentration 1000-fold greater than its Ki(cathepsin B), gave no significant decrease in lung colonization by the B16 tumor cells. Ep475, a stoichiometric irreversible peptide inhibitor of cathepsin B-like proteases, also did not significantly inhibit metastatic foci formation. Introduction of selective inhibitors of urokinase PA, tert-butyloxycarbonylglutamylglycyl-argininal and H-glutamylglycylargininal at concentrations near its Ki, produced no significant decrease in mouse lung colonization. The selective thrombin inhibitor D-phenylalanylprolylargininal infused to a steady state concentration 100-fold greater than its Ki dramatically increased B16 melanoma colonization of mouse lung. The results indicate that neither secreted cathepsin B-like nor urokinase PA have roles in B16 colonization of mouse lung, while thrombin may have a role in preventing metastasis. These experiments do not eliminate roles for a cathepsin B-like enzyme or urokinase PA in the initial steps of the metastatic process.


Asunto(s)
Metástasis de la Neoplasia , Inhibidores de Proteasas/farmacología , Animales , Catepsina B , Catepsinas/antagonistas & inhibidores , Cisteína Endopeptidasas , Relación Dosis-Respuesta a Droga , Endopeptidasas , Femenino , Fibrinólisis/efectos de los fármacos , Leucina/análogos & derivados , Leucina/farmacología , Leupeptinas/farmacología , Neoplasias Pulmonares/secundario , Melanoma/patología , Ratones , Ratones Endogámicos C57BL , Péptido Hidrolasas/análisis , Activadores Plasminogénicos/antagonistas & inhibidores , Inactivadores Plasminogénicos , Serina Endopeptidasas , Trombina/antagonistas & inhibidores , Trombosis/patología
13.
Cancer Res ; 52(5): 1144-8, 1992 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-1737373

RESUMEN

Six well characterized human medulloblastoma cell lines (D283 Med, Daoy, D341 Med, D384 Med, D425 Med, and D458 Med) were examined for the expression of O6-methylguanine-DNA methyltransferase (MGMT) by activity and Western and Northern blot analysis. High levels of MGMT activity were present in D283 Med, Daoy, D341 Med, and D384 Med (1.36, 0.80, 1.68, and 1.62 pmol/mg of protein, respectively), but negligible MGMT activity was detected in D425 Med and D458 Med (0.06 and 0.05 pmol/mg of protein, respectively), which were derived separately at different times from the same patient. The presence of MGMT protein and its transcript was demonstrated in D283 Med, Daoy, D341 Med, and D384 Med, but both the protein and the mRNA were undetectable in D425 Med and D458 Med. Nevertheless, all six cell lines contained an apparently unaltered MGMT gene, as determined by Southern blot analysis. The absence of MGMT activity in D425 Med and D458 Med is likely due to the absence of the protein, resulting from a lack of transcription of the MGMT gene. The varying levels of expression of MGMT in medulloblastoma cells found in this study should provide a molecular basis for drug design and selection in chemotherapy of this tumor.


Asunto(s)
Meduloblastoma/enzimología , Metiltransferasas/metabolismo , ARN Mensajero/metabolismo , Northern Blotting , Western Blotting , Humanos , O(6)-Metilguanina-ADN Metiltransferasa , Células Tumorales Cultivadas
14.
J Leukoc Biol ; 66(2): 310-4, 1999 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10449174

RESUMEN

To further enhance chimerism, 229 primary allograft recipients have received perioperative intravenous infusion of a single dose of 3 to 6 X 10(8) unmodified donor bone marrow (BM) cells/kg body weight. In addition, 42 patients have been accrued in a concurrent protocol involving multiple (up to three) sequential perioperative infusions of 2 x 10(8) BM cells/kg/day from day 0-2 posttransplantation (PTx). Organ recipients (n = 133) for whom BM was not available were monitored as controls. The infusion of BM was safe and except for 50 (18%), all study patients have optimal graft function. Of the control patients, allografts in 30 (23%) have been lost during the course of follow-up. The cumulative risk of acute cellular rejection (ACR) was statistically lower in the study patients compared with that of controls. It is interesting that, 62% of BM-augmented heart recipients were free of ACR (Grade > or = 3A) in the first 6 months PTx compared to controls. The incidence of obliterative bronchiolitis was also statistically lower in study lung recipients (3.8%) compared with the contemporaneously acquired controls (31%). The levels of donor cell chimerism were at least a log higher in the peripheral blood of majority of the study patients compared with that of controls. The incidence of donor-specific hyporeactivity, as determined by one-way mixed leukocyte reaction, was also higher in those BM-augmented liver, kidney, and lung recipients that could be evaluated compared to controls.


Asunto(s)
Células de la Médula Ósea/inmunología , Trasplante de Médula Ósea/inmunología , Tolerancia Inmunológica/inmunología , Transfusión de Leucocitos , Leucocitos/inmunología , Trasplante de Órganos , Femenino , Estudios de Seguimiento , Rechazo de Injerto/inmunología , Trasplante de Corazón/inmunología , Herpesvirus Humano 4/inmunología , Humanos , Incidencia , Trasplante de Riñón/inmunología , Trasplante de Hígado/inmunología , Trasplante de Pulmón/inmunología , Trastornos Linfoproliferativos/epidemiología , Trastornos Linfoproliferativos/inmunología , Quimera por Trasplante/inmunología , Trasplante Homólogo/inmunología
15.
J Neuroimmunol ; 36(1): 41-55, 1992 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-1370958

RESUMEN

Tenascin expression was evaluated in 21 human glioma cell lines and in normal adult tissue extracts by Western and Northern blotting. The cell lines differed in their relative expression of tenascin in the cell-associated and supernatant compartments. Glioma cell line tenascin production was not uniformly stimulated by changes in fetal bovine serum concentration in the growth media. In most glioma cell lines and normal tissue extracts, reducing Western blots and Northern blots revealed two tenascin species, respectively: a major 340 kDa polypeptide and a 9 kb RNA transcript accompanied by a less intense 250 kDa polypeptide and 7 kDa RNA species. In U-87 MG and in normal adult kidney extracts, however, the 250 kDa band and 7 kb transcript were more prominent. Quantitation of tenascin in the glioma lines revealed variable levels that were significantly higher than those in the tissue extracts.


Asunto(s)
Moléculas de Adhesión Celular Neuronal/metabolismo , Proteínas de la Matriz Extracelular/metabolismo , Glioma/metabolismo , Animales , Northern Blotting , Western Blotting , Encéfalo/metabolismo , Moléculas de Adhesión Celular Neuronal/química , Moléculas de Adhesión Celular Neuronal/genética , Medios de Cultivo , Relación Dosis-Respuesta a Droga , Electroforesis en Gel de Poliacrilamida , Proteínas de la Matriz Extracelular/química , Proteínas de la Matriz Extracelular/genética , Glioma/patología , Humanos , Immunoblotting , Riñón/metabolismo , ARN Mensajero/metabolismo , Valores de Referencia , Tenascina , Extractos de Tejidos/metabolismo , Células Tumorales Cultivadas
16.
Am J Med Genet ; 82(2): 155-60, 1999 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-9934981

RESUMEN

Primary ciliary dyskinesia (PCD) is a genetic disease characterized by abnormal ciliary structure and function, impaired mucociliary clearance, and chronic middle ear, sinus, and lung disease. PCD is associated with situs inversus in approximately 50% of the patients. One proposed explanation for this relationship is that normal ciliary function plays a role in normal organ orientation, whereas organ orientation in PCD is a random event because of dysfunctional cilia in early embryonic development. Another hypothesis for the association between PCD and situs inversus is that mutated genes in PCD not only cause defective cilia, but are also linked to the control of organ laterality, such that abnormalities in this molecular pathway result in random left-right asymmetry. We report on a set of monozygotic twin women with PCD. In both patients, deficiency of the inner dynein arms was noted on ciliary ultrastructural analysis, associated with a clinical syndrome of bronchiectasis, chronic sinusitis, and middle ear disease. One of the twins has situs solitus, the other has situs inversus totalis. DNA analysis confirmed that the twins are monozygotic. This is consistent with the hypothesis that situs inversus occurring in patients with primary ciliary dyskinesia is a random but "complete" event in the fetal development of patients with PCD.


Asunto(s)
Trastornos de la Motilidad Ciliar/fisiopatología , Enfermedades en Gemelos , Situs Inversus/diagnóstico por imagen , Gemelos Monocigóticos , Adulto , Cilios/ultraestructura , Femenino , Humanos , Microscopía Electrónica , Radiografía , Situs Inversus/fisiopatología
17.
In Vitro Cell Dev Biol Anim ; 33(3): 212-7, 1997 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9112131

RESUMEN

We are studying the regulation of ciliated cell differentiation using an in vitro model of tracheal regeneration. Previously, we reported that removal of growth stimulating compounds such as epidermal growth factor (EGF) and cholera toxin reduced DNA synthesis and cell number while increasing ciliated cell differentiation (Clark et al., 1995). This result suggested that the induction of growth arrest may stimulate terminal differentiation of airway epithelial cells into ciliated cells. Transforming growth factor beta s (TGF beta s) inhibit epithelial cell proliferation and have also been shown to stimulate epithelial cell differentiation. In this study, the effect of TGF beta 1 on growth and ciliated cell differentiation of rat tracheal epithelial (RTE) cells was examined. TGF beta 1 inhibited [3H]thymidine incorporation by RTE cells in a dose-dependent manner. A 40% inhibition was observed after a 24-h incubation with 10 pM TGF beta 1. Continuous treatment with TGF beta 1 (1-50 pM) also reduced cell number during the time when ciliogenesis occurs. This reduction resulted in part from a loss of cells through exfoliation, in addition to the inhibition of proliferation. The exfoliated cells exhibited several morphological features characteristic of apoptosis, including shrunken cells, condensed and fragmented nuclei, and intact organelles. In addition, electrophoretic analysis of genomic DNA analysis isolated from exfoliated cells demonstrated the presence of a nucleosomal ladder. However, in contrast to the removal of EGF1 treatment with TGF beta 1 for 7 d did not increase ciliated cell differentiation. TGF beta 1 is, therefore, capable of inhibiting proliferation and increasing apoptosis in RTE cells without stimulating ciliated cell differentiation.


Asunto(s)
Apoptosis , Diferenciación Celular , División Celular , Tráquea/citología , Factor de Crecimiento Transformador beta/farmacología , Animales , Recuento de Células , Células Cultivadas , Cilios , ADN/biosíntesis , Células Epiteliales , Masculino , Microscopía Electrónica , Ratas , Ratas Endogámicas F344
18.
Ginekol Pol ; 64(2): 102-5, 1993 Feb.
Artículo en Polaco | MEDLINE | ID: mdl-8359725

RESUMEN

The authors described a course of pregnancy and delivery of pregnant women who was admitted to the hospital in the third trimester with symptoms of sepsis in course of the pyelonephritis. Signs of a kidney insufficiency and pulmonary oedema were observed. During hospitalization ultrasound examination showed polycystic kidneys.


Asunto(s)
Enfermedades Renales Poliquísticas/diagnóstico por imagen , Complicaciones del Embarazo/diagnóstico por imagen , Adulto , Femenino , Humanos , Embarazo , Complicaciones Infecciosas del Embarazo/etiología , Pielonefritis/etiología , Ultrasonografía
19.
Transplant Proc ; 44(10): 2910-2, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23194995

RESUMEN

BACKGROUND: The determination of kidney function plays a pivotal role in living donors renal assessment because of the long-term hazards of life with one kidney. Guidelines recommend estimation of glomerular filtration rate (GFR) by the Modification of Renal Disease (MDRD) or Cockroft-Gault equations for people with normal or near-normal renal function. Cystatin C (CysC) has been introduced as an alternative endogenous marker of GFR. OBJECTIVE: The objective of the study was to evaluate residual renal function among living kidney donors by comparing serum CysC concentrations and estimated GFR according to the MDRD formula or the Cockroft-Gault equation. PATIENTS AND METHODS: Forty living kidney donors showed a mean age of 46.14 years. Their GFR was estimated according to the abbreviated MDRD (aMDRD) and Cockroft-Gault formula adjusted for body surface area. Twenty-two donors underwent diethylenetriaminepentaacetic acid (DTPA) renal studies. Serum CysC concentrations were measured during the last follow-up visit. GFR values according to Cockroft-Gault formula and MDRD formula were correlated with CysC concentrations using Pearson's linear correlation. RESULTS: Mean GFR according to the aMDRD formula and Cocroft-Gault formula decreased after nephrectomy. The Cockroft-Gault formula overestimated the DTPA GFR in our study. No significant differences were observed between DTPA GFR and GFR estimated using the aMDRD equation. The rate of GFR decrease was approximately 0.8 mL/min/1.73 m(2) per year. No significant correlation was observed between serum CysC concentration and GFR. Microalbuminuria was observed in one patient after nephrectomy. CONCLUSIONS: aMDRD equation to estimate GFR is more precise than Cockroft-Gault formula and cystatin C in living kidney donors after nephrectomy and should be preferred model in these patients.


Asunto(s)
Cistatina C/sangre , Tasa de Filtración Glomerular , Trasplante de Riñón/métodos , Riñón/fisiopatología , Donadores Vivos , Nefrectomía , Recolección de Tejidos y Órganos/métodos , Adulto , Anciano , Biomarcadores/sangre , Femenino , Humanos , Riñón/diagnóstico por imagen , Riñón/metabolismo , Trasplante de Riñón/efectos adversos , Modelos Lineales , Masculino , Persona de Mediana Edad , Modelos Biológicos , Nefrectomía/efectos adversos , Valor Predictivo de las Pruebas , Cintigrafía , Radiofármacos , Pentetato de Tecnecio Tc 99m , Recolección de Tejidos y Órganos/efectos adversos , Resultado del Tratamiento
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