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1.
Pharmacogenomics J ; 18(3): 436-443, 2018 05 22.
Artículo en Inglés | MEDLINE | ID: mdl-29205207

RESUMEN

Translation of drug candidates into clinical settings requires demonstration of preclinical efficacy and formal toxicology analysis for filling an Investigational New Drug (IND) application with the US Food and Drug Administration (FDA). Here, we investigate the membrane-associated glucose response protein 78 (GRP78) as a therapeutic target in leukemia and lymphoma. We evaluated the efficacy of the GRP78-targeted proapoptotic drug bone metastasis targeting peptidomimetic 78 (BMTP-78), a member of the D(KLAKLAK)2-containing class of agents. BMTP-78 was validated in cells from patients with acute myeloid leukemia and in a panel of human leukemia and lymphoma cell lines, where it induced dose-dependent cytotoxicity in all samples tested. Based on the in vitro efficacy of BMTP-78, we performed formal good laboratory practice toxicology studies in both rodents (mice and rats) and nonhuman primates (cynomolgus and rhesus monkeys). These analyses represent required steps towards an IND application of BMTP-78 for theranostic first-in-human clinical trials.


Asunto(s)
Evaluación Preclínica de Medicamentos , Proteínas de Choque Térmico/genética , Leucemia/tratamiento farmacológico , Linfoma/tratamiento farmacológico , Peptidomiméticos/administración & dosificación , Animales , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Chaperón BiP del Retículo Endoplásmico , Proteínas de Choque Térmico/antagonistas & inhibidores , Humanos , Leucemia/patología , Linfoma/patología , Macaca fascicularis , Macaca mulatta , Ratones , Terapia Molecular Dirigida , Peptidomiméticos/efectos adversos , Primates , Ratas , Estados Unidos , United States Food and Drug Administration
2.
Clin Exp Immunol ; 174(1): 89-96, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23763437

RESUMEN

Chronic granulomatous disease (CGD) patients are highly susceptible to invasive aspergillosis and might benefit from aspergillus-specific T cell immunotherapy, which has shown promise in treating those with known T cell defects such as haematopoietic stem cell transplant (HSCT) recipients. But whether such T cell defects contribute to increased risks for aspergillus infection in CGD is unclear. Hence, we set out to characterize the aspergillus-specific T cell response in CGD. In murine CGD models and in patients with CGD we showed that the CD4(+) T cell responses to aspergillus were unimpaired: aspergillus-specific T cell frequencies were even elevated in CGD mice (P < 0·01) and humans (P = 0·02), compared to their healthy counterparts. CD4-depleted murine models suggested that the role of T cells might be redundant because resistance to aspergillus infection was conserved in CD4(+) T cell-depleted mice, similar to wild-type animals. In contrast, mice depleted of neutrophils alone or neutrophils and CD4(+) T cells developed clinical and pathological evidence of pulmonary aspergillosis and increased mortality (P < 0·05 compared to non-depleted animals). Our findings that T cells in CGD have a robust aspergillus CD4(+) T cell response suggest that CD4(+) T cell-based immunotherapy for this disease is unlikely to be beneficial.


Asunto(s)
Aspergilosis Broncopulmonar Alérgica/inmunología , Aspergilosis Broncopulmonar Alérgica/terapia , Enfermedad Granulomatosa Crónica/inmunología , Enfermedad Granulomatosa Crónica/terapia , Inmunoterapia Adoptiva , Linfocitos T/inmunología , Linfocitos T/microbiología , Animales , Aspergillus fumigatus/inmunología , Línea Celular , Células Cultivadas , Humanos , Inmunoterapia Adoptiva/métodos , Glicoproteínas de Membrana/deficiencia , Glicoproteínas de Membrana/genética , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , NADPH Oxidasa 2 , NADPH Oxidasas/deficiencia , NADPH Oxidasas/genética , Linfocitos T/patología , Células TH1/inmunología , Células TH1/microbiología , Células TH1/trasplante
3.
J Med Primatol ; 42(3): 158-60, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23534377

RESUMEN

BACKGROUND: A 4-year-old rhesus macaque presented with acute, progressive paresis of the extremities. METHODS: A complete blood count, serum biochemical analysis, neurologic exam and necropsy were performed. RESULTS: The clinical, histopathological, and immunohistochemical findings confirmed a high-grade intramedullary glial tumor of the spinal cord that was most consistent with an ependymoma. CONCLUSIONS: We describe a case of a naturally occurring spontaneous spinal cord neoplasia in a non-human primate.


Asunto(s)
Ependimoma/veterinaria , Macaca mulatta , Enfermedades de los Monos/diagnóstico , Paresia/veterinaria , Neoplasias de la Médula Espinal/veterinaria , Animales , Ependimoma/complicaciones , Ependimoma/diagnóstico , Resultado Fatal , Femenino , Enfermedades de los Monos/etiología , Paresia/diagnóstico , Paresia/etiología , Médula Espinal/patología , Neoplasias de la Médula Espinal/complicaciones , Neoplasias de la Médula Espinal/diagnóstico
4.
Antimicrob Agents Chemother ; 55(7): 3603-8, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21518842

RESUMEN

We evaluated the in vitro and in vivo activity of a novel topical myeloperoxidase-mediated antimicrobial, E-101 solution, against 5 multidrug-resistant Acinetobacter baumannii isolates recovered from wounded American soldiers. Time-kill studies demonstrated rapid bactericidal activity against all A. baumannii strains tested in the presence of 3% blood. The in vitro bactericidal activity of E-101 solution against A. baumannii strains was confirmed in a full-thickness excision rat model. Additional in vivo studies appear warranted.


Asunto(s)
Infecciones por Acinetobacter/tratamiento farmacológico , Acinetobacter baumannii/efectos de los fármacos , Acinetobacter baumannii/patogenicidad , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Farmacorresistencia Bacteriana Múltiple/efectos de los fármacos , Personal Militar , Animales , Masculino , Pruebas de Sensibilidad Microbiana , Ratas , Ratas Sprague-Dawley
5.
bioRxiv ; 2021 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-34159332

RESUMEN

The continuing emergence of SARS-CoV-2 variants calls for regular assessment to identify differences in viral replication, shedding and associated disease. In this study, African green monkeys were infected intranasally with either a contemporary D614G or the UK B.1.1.7 variant. Both variants caused mild respiratory disease with no significant differences in clinical presentation. Significantly higher levels of viral RNA and infectious virus were found in upper and lower respiratory tract samples and tissues from B.1.1.7 infected animals. Interestingly, D614G infected animals showed significantly higher levels of viral RNA and infectious virus in rectal swabs and gastrointestinal tract tissues. Our results indicate that B.1.1.7 infection in African green monkeys is associated with increased respiratory replication and shedding but no disease enhancement similar to human B.1.1.7 cases. ONE-SENTENCE SUMMARY: UK B.1.1.7 infection of African green monkeys exhibits increased respiratory replication and shedding but no disease enhancement.

6.
J Exp Med ; 161(4): 705-17, 1985 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-2580037

RESUMEN

The linear immunogenic and antigenic structure of E. coli Gal-Gal pili from the recombinant strain HU 849 was investigated with nine synthetic peptides corresponding to regions of the pilus sequence predicted to contain hydrophilic beta-turns. Five peptides, as bovine serum albumin conjugates, were found by anti-HU 849 pilus serum and were thus designated "immunogenic epitopes." Peptides corresponding to R 25-38, R 38-50, and R 48-61 (which jointly comprise the single intramolecular disulfide loop), and R 103-116, were bound in low titer. A prominent immunogenic epitope was specified by a peptide corresponding to R 65-75. Four peptides, as thyroglobulin conjugates, elicited antisera in rabbits that bound intact HU 849 pili. These were designated "antigenic epitopes." Two prominent antigenic epitopes were localized to peptides corresponding to R 5-12 and R 93-104, whereas peptides corresponding to R 65-75 and R 119-131 represented two minor antigenic epitopes. None of the peptide antisera bound Gal-Gal pili from heterologous strains except anti-R 93-104 and anti-R 5-12. In 8 of the 10 Gal-Gal-binding pyelonephritis isolates tested, anti-R 5-12 detected a protein with an apparent molecular weight of 18,000 co-migrating with several Gal-Gal pili. Anti-R 93-104 detected a corresponding protein in 4 of 8 fecal and 7 of 12 pyelonephritis Gal-Gal-binding isolates; however, it also bound apparently unrelated proteins of higher molecular weight.


Asunto(s)
Antígenos Bacterianos/análisis , Epítopos/análisis , Escherichia coli/inmunología , Fimbrias Bacterianas/inmunología , Galactosamina/inmunología , Galactosa/inmunología , Secuencia de Aminoácidos , Animales , Escherichia coli/metabolismo , Femenino , Fimbrias Bacterianas/metabolismo , Galactosamina/metabolismo , Galactosa/metabolismo , Pruebas de Hemaglutinación , Humanos , Sueros Inmunes/farmacología , Péptidos/síntesis química , Péptidos/inmunología , Pielonefritis/inmunología , Conejos , Receptores Inmunológicos/análisis
7.
J Exp Med ; 158(5): 1713-19, 1983 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-6195290

RESUMEN

Chromosomal genes encoding the MS and Gal-Gal binding properties have been cloned into separate recombinants and their respective pili characterized. Hapten inhibition of hemagglutination with synthetic carbohydrate receptor analogues and carbohydrate-adsorbed latex agglutination studies indicate that Gal-Gal and MS pili collectively exhibit the binding properties of the parent strain. MS pili migrated in SDS-PAGE with an Mr of 19 kdaltons and 17 kdaltons; the Mr of Gal-Gal pili was 17.5 kdaltons. The pili are chemically similar by amino acid composition and when the N-terminal cysteines are aligned, 8 of the 13 residues between positions 9 and 22 are homologous. Further, carboxy-terminal sequence homology was inferred from the carboxypeptidase digestion of a MS pili and the sequence of a carboxy-terminal tryptic peptide from Gal-Gal pili.


Asunto(s)
Disacáridos/metabolismo , Escherichia coli/metabolismo , Fimbrias Bacterianas/metabolismo , Galactosa/metabolismo , Manosa/farmacología , Pruebas de Aglutinación , Secuencia de Aminoácidos , Aminoácidos/análisis , Animales , Proteínas Bacterianas/análisis , Epítopos/inmunología , Escherichia coli/genética , Fimbrias Bacterianas/inmunología , Cobayas , Pruebas de Hemaglutinación , Humanos , Recombinación Genética
8.
J Exp Med ; 160(4): 1253-8, 1984 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-6207263

RESUMEN

The heat-stable enterotoxin ST Ib produced by enterotoxigenic E. coli strains shares a sequence homology with the sea snail neurotoxin, conotoxin GI. Rabbit antisera were raised against synthetic analogs of these toxins and to a six-residue peptide representing the region common to both toxins. Results from enzyme-linked immunosorbent assays indicate that the homologous region of both toxins represents part of their antigenic site. The lack of cross-reactivity exhibited by the six-residue common domain with serum directed against either toxin suggests that this region probably retains a similar conformation in the intact toxins but not in the isolated fragment.


Asunto(s)
Toxinas Bacterianas , Conotoxinas , Enterotoxinas/análisis , Epítopos/análisis , Venenos de Moluscos/análisis , Secuencia de Aminoácidos , Animales , Antitoxinas/farmacología , Reacciones Cruzadas , Enterotoxinas/inmunología , Enterotoxinas/toxicidad , Epítopos/inmunología , Proteínas de Escherichia coli , Femenino , Ratones , Venenos de Moluscos/inmunología , Venenos de Moluscos/toxicidad , Hipotonía Muscular/etiología , Parálisis/etiología , Conejos , Caracoles
9.
Science ; 214(4521): 660-2, 1981 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-7292005

RESUMEN

Natural abundance carbon-13 nuclear magnetic resonances (NMR) from human arm and rat tissues have been observed in vivo. These signals arise primarily from triglycerides in fatty tissue. Carbon-13 NMR was also used to follow, in a living rat, the conversion of C-1-labeled glucose, which was introduced into the stomach, to C-1-labeled liver glycogen. The carbon-13 sensitivity and resolution obtained shows that natural abundance carbon-13 NMR will be valuable in the study of disorders in fat metabolism, and that experiments with substrates labeled with carbon-13 can be used to study carbohydrate metabolism in vivo.


Asunto(s)
Carbono/metabolismo , Espectroscopía de Resonancia Magnética/métodos , Tejido Adiposo/efectos de los fármacos , Animales , Isótopos de Carbono , Glucosa/metabolismo , Humanos , Glucógeno Hepático/metabolismo , Modelos Estructurales , Ratas , Factores de Tiempo
10.
J Clin Invest ; 83(6): 2102-8, 1989 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-2566625

RESUMEN

The initial pathogenic step in nonobstructive Escherichia coli pyelonephritis usually involves the binding of a bacterial adhesin with host uroepithelial glycoprotein receptors containing the D-Gal p alpha 1----4 D-Gal p beta 1 (Gal-Gal) moiety. In this study, groups of mice were immunized with Gal-Gal pili and challenged 2 wk later intravesicularly with E. coli strains expressing homologous or heterologous pili. 63 of 129 pili-immunized mice (49%) were protected from subsequent E. coli renal colonization compared with 5 of 85 control mice (6%). Among mice that had E. coli cultured from their right kidney, control mice had greater bacterial colony counts than pili-immunized animals (P less than 0.05). Light microscopic examination of kidneys demonstrated less histopathology among pili immunized mice than among control mice (P less than 0.05). Protection correlated with the presence of specific IgG antibodies in the urine and serum that bind to the major pilin structural polypeptide and not to the Gal-Gal pili tip adhesin per se. These results support the concept that immunization with a bacterial surface-coat constituent can prevent mucosal infection by interfering with colonization. Also Gal-Gal pili of E. coli represent a suitable candidate for immunoprophylaxis against pyelonephritis.


Asunto(s)
Proteínas de la Membrana Bacteriana Externa/uso terapéutico , Vacunas Bacterianas/uso terapéutico , Infecciones por Escherichia coli/prevención & control , Escherichia coli/inmunología , Fimbrias Bacterianas/inmunología , Glicoesfingolípidos/inmunología , Pielonefritis/prevención & control , Animales , Anticuerpos Antibacterianos/análisis , Modelos Animales de Enfermedad , Escherichia coli/crecimiento & desarrollo , Infecciones por Escherichia coli/inmunología , Infecciones por Escherichia coli/microbiología , Femenino , Proteínas Fimbrias , Humanos , Riñón/microbiología , Ratones , Ratones Endogámicos BALB C , Pielonefritis/inmunología , Pielonefritis/microbiología , Proteínas Recombinantes/uso terapéutico
11.
J Clin Invest ; 75(2): 347-60, 1985 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-2857730

RESUMEN

Most human pyelonephritis Escherichia coli isolates express both mannose (MS)- and globoside (Gal-Gal)-binding pili. An ascending E. coli urinary tract infection model was established in the 16-wk-old female BALB/c mouse to compare the pathogenic significance of MS and Gal-Gal pili and their efficacy as vaccines for the prevention of pyelonephritis. The distribution and density of pilus receptor compounds in urogenital tissues and as soluble compounds in urine were determined with antibodies to the synthetic receptor analogues, alpha D-Gal(1----4) beta D-Gal and alpha D-Man(1----2) alpha D-Man. Both carbohydrates were detected in vagina, bladder, ureter, and renal pelvis epithelium and in collecting duct and tubular cells. A pilus receptor compound also was detected in urine. It competitively inhibited the binding capacity of MS pili and was found to be physically, chemically, and immunologically related to Tamm-Horsfall uromucoid. Infectivity and invasiveness were quantitatively and histologically characterized for four E. coli strains: J96, a human pyelonephritis strain that expresses both MS and Gal-Gal pili; two recombinant strains prepared from J96 chromosomal DNA encoding MS pili or Gal-Gal pili; and the nonpiliated K12 recipient. Intravesicular administration of J96 (10(6) colony-forming units [CFU]) resulted in renal colonization and invasion in each of nine mice. The Gal-Gal clone (10(6) CFU) colonized the kidneys in each of 10 mice but did not invade. In contrast, the MS clone (10(6) CFU) did not colonize renal epithelium or invade. This effect was superceded when larger doses (greater than or equal to 10(10) CFU) of the MS clone were administered in volumes that cause acute vesicoureteric reflux. The efficacy was determined of vaccines composed of pure MS or Gal-Gal pili or the lipopolysaccharide containing O somatic antigen of the challenge strain, J96. The Gal-Gal pilus vaccine blocked renal colonization in 19 of 22 mice and renal invasion in 10 of 11 mice. Gal-Gal pili may be useful immunogens for the prevention of pyelonephritis in anatomically normal urinary tracts.


Asunto(s)
Infecciones por Escherichia coli/etiología , Fimbrias Bacterianas/fisiología , Pielonefritis/etiología , Animales , Modelos Animales de Enfermedad , Escherichia coli/fisiología , Infecciones por Escherichia coli/prevención & control , Femenino , Fimbrias Bacterianas/inmunología , Globósidos/metabolismo , Humanos , Inmunización , Manosa/metabolismo , Ratones , Ratones Endogámicos BALB C , Pielonefritis/prevención & control
12.
J Clin Invest ; 79(6): 1756-63, 1987 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-3294901

RESUMEN

Administration in vivo of recombinant interleukin 2 (rIL-2) to mice induces a polyclonal IgM response. When co-administered with a specific antigen, rIL-2 can enhance concentrations of murine IgM antibodies specific for the antigen by fivefold within 7 d of initial treatment. IgM antibodies that are induced after injection of rIL-2 include antibodies specific for J5, a cell wall core lipopolysaccharide (LPS) antigen that is shared by the different members of the Enterobactericeae family. We report here that mice pretreated with rIL-2 or immunized with J5 antigen 7 d before bacterial challenge were protected from septic death that is caused by intraperitoneal challenges with Escherichia coli. Optimal protection was provided by a combined J5 antigen and rIL-2 treatment. Acquisition of the rIL-2 and J5 antigen-induced protection against lethal bacterial infection coincided temporally with maximal serum IgM titers that also contained IgM antibodies specific for the J5 antigen. In passive immunization experiments, the affinity-purified IgM fraction in sera of rIL-2-treated animals was identified as necessary and sufficient for protection. The IgM-depleted serum had no protective effect. The nonspecific augmentation of host-defense mechanisms without the induction of endotoxin manifestations makes rIL-2 a potential candidate to any alternative LPS-containing vaccines for the prevention of bacterial infections by gram-negative organisms since the core LPS antigen is shared among gram-negative bacteria.


Asunto(s)
Anticuerpos Antibacterianos/biosíntesis , Antígenos Bacterianos/inmunología , Inmunoglobulina M/biosíntesis , Interleucina-2/uso terapéutico , Lipopolisacáridos/inmunología , Sepsis/prevención & control , Animales , Escherichia coli/inmunología , Infecciones por Escherichia coli/complicaciones , Femenino , Inmunización , Ratones , Ratones Endogámicos BALB C , Peritonitis/complicaciones , Proteínas Recombinantes/uso terapéutico , Sepsis/etiología , Sepsis/inmunología
13.
J Clin Invest ; 89(3): 1032-9, 1992 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-1541664

RESUMEN

Cytokines may play an important role in the regulation of host defense against local bacterial infections. We have evaluated the local production of cytokines in a BALB/c mouse model of Escherichia coli pyelonephritis. Kidneys, draining lymph nodes, and spleens, were harvested at specific time intervals after bladder inoculation with E. coli corresponding to the stages of renal infection, infiltration, and bacterial clearance seen in this model. The presence of messenger RNA for specific cytokines (interleukins 1 through 6, chemotactic factors, granulocyte and granulocyte macrophage-colony stimulating factor (GM-CSF), tumor necrosis factor (TNF alpha) and beta, IFN gamma, transforming growth factor (TGF beta), and cytokine synthesis inhibitory factor (CSIF)/IL-10) was determined by polymerase chain reaction (PCR) amplification of reverse transcribed RNA. We have demonstrated mRNA encoding IL-1, IL-6, G-CSF, GM-CSF, TNF alpha, H400 (a protein homologous to a family of chemotactic factors and identical to MIP-1 beta), and CSIF/IL-10 in the kidney at 12 h and 1, 2, and 3 d after bacterial challenge. No signal was seen in normal animals or in mice after 5 d. This pattern of cytokine expression was observed only in renal tissues suggesting a localized response. IL-6 was present in the urine at 4 h with rapid resolution to baseline levels by 24 to 48 h. In contrast, IL-6 was not usually detectable in the serum. TNF alpha was not detectable in the serum or urine during the course of the infection. By immunohistochemical staining of kidney sections we have shown that IL-6 is produced predominantly by mesangial cells rather than by the inflammatory infiltrate. This study provides additional evidence utilizing novel techniques that specific cytokines are produced locally in response to bacterial infections. The time course of production demonstrated in this model supports the important role of cytokines in natural host resistance to local infection.


Asunto(s)
Citocinas/biosíntesis , Infecciones por Escherichia coli/metabolismo , Pielonefritis/metabolismo , Animales , Secuencia de Bases , Infecciones por Escherichia coli/patología , Femenino , Interleucina-6/análisis , Ratones , Ratones Endogámicos BALB C , Datos de Secuencia Molecular , Pielonefritis/patología , ARN Mensajero/análisis , Factor de Necrosis Tumoral alfa/análisis
14.
J Clin Invest ; 77(6): 1812-6, 1986 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-3711336

RESUMEN

In vitro and in vivo studies have suggested that human complement component C5a plays a key role in neutrophil injury in the adult respiratory distress syndrome (ARDS). First, using leukocyte aggregometry, we demonstrated that the addition of a recently developed rabbit anti-human polyclonal antibody to C5a des arg to endotoxin-activated plasma prevented leukocyte aggregation in vitro. We then administered the anti-C5a des arg antibody to septic primates (Macaca fascicularis). Three groups of primates, control, septic, and anti-C5a antibody treated septic, were studied (n = 4 in each group). A 30-min infusion of Escherichia coli (1 X 10(10)/kg) resulted in severe sepsis and ARDS. Primates were killed 4 h after completion of the E. coli infusion. Septic animals not treated with anti-C5a antibody had 75% mortality (3/4), decreased oxygenation, severe pulmonary edema, and profound hypotension. Septic primates treated with anti-C5a antibodies did not die and did not develop decreased oxygenation (P less than 0.05) or increased extravascular lung water (P less than 0.05). They also had a marked recovery in their mean arterial blood pressure (P less than 0.05). This study demonstrates that treatment with rabbit anti-human C5a des arg antibodies attenuates ARDS and some of the systemic manifestations of sepsis in nonhuman primates.


Asunto(s)
Anticuerpos/análisis , Complemento C5/inmunología , Síndrome de Dificultad Respiratoria/inmunología , Sepsis/complicaciones , Animales , Presión Sanguínea , Agregación Celular , Complemento C5/análogos & derivados , Complemento C5a , Complemento C5a des-Arginina , Frecuencia Cardíaca , Leucocitos/citología , Macaca fascicularis , Presión Esfenoidal Pulmonar , Síndrome de Dificultad Respiratoria/complicaciones , Resistencia Vascular
15.
Circ Res ; 88(9): 918-24, 2001 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-11349001

RESUMEN

ATP-sensitive K (K(ATP)) channels are inhibited by cytosolic ATP, a defining property that implicitly links these channels to cellular metabolism. Here we report a direct link between fatty acid metabolism and K(ATP) channels in cardiac muscle cells. Long-chain (LC) acyl-coenzyme A (CoA) esters are synthesized from fatty acids and serve as the principal metabolic substrates of the heart. We have studied the effects of LC acyl-CoA esters and LC fatty acids on K(ATP) channels of isolated guinea pig ventricular myocytes and compared them with the effects of phosphatidylinositol 4,5-bisphosphate (PIP(2)). Application of oleoyl-CoA (0.2 or 1 micromol/L), a naturally occurring acyl-CoA ester, to the cytosolic side of excised patches completely prevented rundown of K(ATP) channels, but not of Kir2 channels. The open probability of K(ATP) channels measured in the presence of oleoyl-CoA or PIP(2) was voltage dependent, increasing with depolarization. Oleoyl-CoA greatly reduced the ATP sensitivity of K(ATP) channels. At a concentration of 2 micromol/L, oleoyl-CoA increased the half-maximal inhibitory concentration of ATP >200-fold. The time course of the decrease in ATP sensitivity was much faster during application of oleoyl-CoA than during application of PIP(2). The effects of PIP(2), but not of oleoyl-CoA, were inhibited by increasing Ca(2+) to 1 mmol/L. Oleate (C18:1; 10 micromol/L), the precursor of oleoyl-CoA, inhibited K(ATP) channels activated by oleoyl-COA: Palmitoleoyl-CoA and palmitoleate (C16:1) exerted similar reciprocal effects. These findings indicate that LC fatty acids and their CoA-linked derivatives may be key physiological modulators of K(ATP) channel activity in the heart.


Asunto(s)
Acilcoenzima A/farmacología , Adenosina Trifosfato/farmacología , Ácidos Grasos Insaturados/farmacología , Ventrículos Cardíacos/efectos de los fármacos , Canales de Potasio/efectos de los fármacos , Acilcoenzima A/química , Animales , Calcio/farmacología , Relación Dosis-Respuesta a Droga , Cobayas , Ventrículos Cardíacos/citología , Cinética , Potenciales de la Membrana/efectos de los fármacos , Técnicas de Placa-Clamp , Fosfatidilinositol 4,5-Difosfato/farmacología , Canales de Potasio/metabolismo , Factores de Tiempo , Función Ventricular
16.
J Am Coll Cardiol ; 6(6): 1370-82, 1985 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-4067118

RESUMEN

Atrial septal aneurysms have been related (either by association or as potential causes) to systolic clicks, atrial arrhythmias, systemic and pulmonary embolism, atrioventricular valve prolapse and atrial septal defect. To study these associations and the incidence of atrial septal aneurysm, we reviewed 80 consecutive patients (female to male ratio 1.9:1, mean age 47 years, range 1 day to 89 years) who had been identified prospectively as having an atrial septal aneurysm. These were found in 36,200 two-dimensional echocardiographic studies (incidence: 0.22% overall; 0.29% in the last year of the study done between 1978 and 1984). Three types of fossa ovalis aneurysm and one type of aneurysm involving the entire atrial septum were observed; a fossa ovalis aneurysm with leftward projection and excursion of less than 5 mm or an aneurysm involving the entire atrial septum with rightward projection was not observed. Atrial septal aneurysm occurred more often as an isolated abnormality than in association with other cardiac malformations, although all patients with an aneurysm involving the entire atrial septum had complex congenital cardiac anomalies of the hypoplastic right heart type. The reported associations between atrial septal aneurysms and atrial septal defect, atrioventricular valve prolapse, midsystolic clicks, atrial arrhythmias and cerebral ischemic events were examined. A hypothesis based on interatrial pressure gradients is proposed to explain the different motions and configurational characteristics of fossa ovalis aneurysms observed in these patients. All patients in whom atrial septal aneurysm is demonstrated should undergo examination for atrial septal defect. Atrial septal aneurysm should be specifically looked for in patients who have these associations and who undergo two-dimensional echocardiography, especially if these abnormalities are unexplained.


Asunto(s)
Aneurisma Cardíaco/diagnóstico , Defectos del Tabique Interatrial/diagnóstico , Adolescente , Adulto , Anciano , Niño , Preescolar , Ecocardiografía , Femenino , Aneurisma Cardíaco/clasificación , Defectos del Tabique Interatrial/clasificación , Humanos , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad
17.
J Am Coll Cardiol ; 13(3): 624-9, 1989 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-2918168

RESUMEN

This study examines the recently reported gender differences in cardiac responses to exercise. The study group consisted of 192 men and 67 women with a low probability of coronary artery disease who underwent supine exercise radionuclide angiography. Men had a lower rest ejection fraction than that of women (0.63 versus 0.66, p = 0.02) and greater increases in ejection fraction with exercise (0.08 versus 0.02, p = 0.0001). The slope relating ejection fraction to metabolic equivalents of exercise (METs) was greater (p = 0.004) for men, even after adjustment for differences in rest ejection fraction and end-diastolic volume index. Compared with men, women had a smaller rest end-diastolic volume index (87 versus 97 ml/m2, p = 0.003) and a greater increase in end-diastolic volume index with exercise (6 versus -2 ml/m2, p = 0.002). The slope relating end-diastolic volume to METs was greater for women, even after adjustment for differences in rest end-diastolic volume index and peak work load. There are clear gender differences in the supine exercise response of ejection fraction and end-diastolic volume that are not explained by differences in exercise capacity.


Asunto(s)
Corazón/fisiología , Esfuerzo Físico , Angiografía por Radionúclidos , Adulto , Presión Sanguínea , Electrocardiografía , Prueba de Esfuerzo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores Sexuales , Volumen Sistólico , Supinación
18.
J Mol Biol ; 196(3): 721-7, 1987 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-3119858

RESUMEN

Using a procedure that minimizes shear forces, the BamHI-derived forked termination of replication intermediate of Bacillus subtilis, called band I DNA, can be extracted with little or no accompanying band II DNA. It has been shown that band II DNA is a product of band I breakdown. Nuclease P1-mediated breakdown of the forked band I DNA proceeds in two steps. The first causes the release of one of the arms as band II DNA; in the second step, the remaining arm is cleaved away to yield the free stem. It is concluded that band I represents the primary termination of replication intermediate. A quantitative assessment of the level of band I in DNA from cells of the merodiploid strain, GSY1127, growing at different rates has been made. For cells grown in a minimal medium, at least, the experimentally measured level of band I is of the order (approx. 60%) of that predicted for a complete block to movement of the clockwise fork at the replication terminus, terC.


Asunto(s)
Bacillus subtilis/genética , Replicación del ADN , Genes Reguladores , Regiones Terminadoras Genéticas , Cromosomas Bacterianos , ADN Bacteriano/genética
19.
Cardiovasc Res ; 28(4): 485-93, 1994 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8181035

RESUMEN

OBJECTIVE: The aim was to determine the metabolic consequence of increasing the osmolality of a crystalloid cardioplegic solution during periods of cardiac arrest. METHODS: Isolated hearts of guinea pig and rat were Langendorff perfused with Krebs-Henseleit solution at 37 degrees C and arrested by an increase in KCl. The rate of oxygen consumption was measured under standard isosmotic conditions and with the osmolality of the perfusate increased by addition of sucrose. RESULTS: Increased osmolality stimulated the rate of myocardial oxygen consumption in a dose dependent manner. At optimal dose (about twice normal osmolality), the oxygen consumption of the arrested heart approximated that of the beating, non-working heart measured prior to arrest. Potentiation of cardiac resting metabolism was greater in the rat than in the guinea pig, whether expressed in absolute terms or relative to the metabolism of the beating heart. Metabolic potentiation was accompanied by an increase of passive or diastolic left ventricular pressure in the rat but not in the guinea pig. The metabolic response was unaffected by coronary vasodilation (adenosine) and by inhibition of Ca2+ channels (verapamil); it was moderately diminished by perfusion with Ca(2+)-free solution. Procaine inhibited the hyperosomotic potentiation of oxygen consumption in a dose dependent manner. CONCLUSIONS: From the absence of passive force development in the guinea pig heart, it appears that the hyperosmotic stimulation of cardiac resting metabolism primarily reflects increased activity of the sarcoplasmic reticular Ca(2+)-ATPase subsequent to release of Ca2+ through a procaine inhibitable channel. Blunting of both the metabolic and mechanical responses in the guinea pig vis-a-vis the rat heart is attributed to the greater capability of the former to buffer myoplasmic Ca2+ via the energetically neutral Na(+)-Ca2+ exchange mechanism.


Asunto(s)
Paro Cardíaco Inducido , Miocardio/metabolismo , Consumo de Oxígeno/fisiología , Adenosina/farmacología , Animales , Calcio/metabolismo , Soluciones Cardiopléjicas , Relación Dosis-Respuesta a Droga , Femenino , Cobayas , Masculino , Concentración Osmolar , Consumo de Oxígeno/efectos de los fármacos , Perfusión , Procaína/farmacología , Ratas , Especificidad de la Especie , Estimulación Química , Sacarosa/farmacología , Verapamilo/farmacología
20.
Bone Marrow Transplant ; 50 Suppl 2: S55-62, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26039209

RESUMEN

We are entering a very exciting era in umbilical cord blood transplantation (UCBT), where many of the associated formidable challenges may become treatable by ex vivo graft manipulation and/or adoptive immunotherapy utilizing specific cellular products. We envisage the use of double UCBT rather than single UCBT for most patients; this allows for greater ability to treat larger patients as well as to manipulate the graft. Ex vivo expansion and/or fucosylation of one cord will achieve more rapid engraftment, minimize the period of neutropenia and also give certainty that the other cord will provide long-term engraftment/immune reconstitution. The non-expanded (and future dominant) cord could be chosen for characteristics such as better HLA matching to minimize GvHD, or larger cell counts to enable part of the unit to be utilized for the development of specific cellular therapies such as the production of virus-specific T-cells or chimeric-antigen receptor T-cells which are reviewed in this study.


Asunto(s)
Trasplante de Células Madre de Sangre del Cordón Umbilical , Refuerzo Inmunológico de Injertos/métodos , Supervivencia de Injerto , Enfermedad Injerto contra Huésped/prevención & control , Ingeniería de Tejidos/métodos , Humanos
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