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1.
Animal ; 17(6): 100818, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37172356

RESUMEN

Body lesions in pigs are a common welfare concern, particularly during the weaning period. These lesions can lead to pain, infection, and impaired mobility, resulting in reduced growth performance and increased mortality. Moreover, weaning stress can affect gut microbiota, immune response and increase the oxidative stress of piglets during this transition period. It has been hypothesised that social stress and body lesions could contribute to affect the gut microbiota, physiological and immune response of piglets. The study aims to evaluate the impact of the body lesions due to social stress on microbial profile, immune response, and oxidative status of weaned piglets. Lesion score (LS) on skin, tail, ear, neck, middle trunk, and hind quarters was measured 1 week (28 days of age, T1) and 7 weeks postweaning (T2) on 45 tail-docked pigs according to the method suggested from the Walfer Quality® (2009) on a scale from 0 to 2. Based on the LS, at T1, piglets were classified as High LS (n = 16), when LS was >1 in at least two of the areas considered, or Low LS (n = 29). At T2, based on the same scoring system and to the LS observed at T1, piglets were divided into four groups: High to Low LS (H-L, n = 11), High to High LS (H-H, n = 5), Low to Low LS (L-L, n = 21) and Low to High LS (L-H, n = 8). Blood and faecal samples were collected at T1 and T2. At T1, pigs with a high LS had a lower biological antioxidant potential compared with the L group (P < 0.02). At T2, the L-H group had a lower Reactive Oxygen Metabolites concentration compared with the H-H group (P = 0.03) while the L-L group had a lower concentration of Immunoglobulin A compared with H-H and L-H groups (P = 0.02 and P = 0.04, respectively). At T1, piglets with high LS had a different microbiota compared to piglets with low LS (R2 = 0.04, P < 0.01). Low LS pigs were characterised by a higher abundance of Firmicutes, Blautia, Eubacterium coprostanoligenes, Faecalibacterium, Megasphaera, Subdoligranulum (P.adj < 0.05), while pigs with high LS were characterised by higher abundance of Bacteroidota, Rikenellaceae RC9, Prevotellaceae UCG-003, uncultured-Lachnospiraceae and uncultured-Oscillospiraceae (P.adj < 0.05). At T2, the H-H group were characterised by Oscillospirales-UCG-010, H-L by Agatobachter and L-L by Alloprevotella (P.adj < 0.05). Overall, this study provides valuable insights into the relationship between body lesions, oxidative stress, and gut microbiota in weaned pigs.


Asunto(s)
Microbioma Gastrointestinal , Porcinos , Animales , Destete , Oxidación-Reducción , Antioxidantes/metabolismo , Estrés Oxidativo
2.
Transplant Proc ; 49(9): 2092-2098, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-29149967

RESUMEN

Cardiovascular disease (CVD) is frequent after kidney transplantation (KT). This study investigated CVD prediction in KT by information available before KT or within 6 months after KT. The study cohort consisted of 629 patients with KT in 2005-10 and with adult age at KT. The end point was incidence up to 2015 of CVD (coronary heart disease, cerebrovascular disease, peripheral artery disease). Graft failure, non-CVD death with functioning graft, and loss to follow-up were considered competing events. CVD prediction was investigated for 34 variables by means of competing-risks regression. Follow-up range was 0.28-10.00 years (mean ± SD, 7.30 ± 3.10). First incident event was CVD in 103 patients and competing events in 146 patients. In the multivariable model for pre-KT variables only, CVD predictors were male sex (hazard ratio [HR], 1.68; 95% confidence interval [CI], 1.06-2.66), diabetic nephropathy (HR, 6.63; 95% CI, 1.81-24.35), pre-KT dialysis for ≥5 years (HR, 1.52; 95% CI, 1.02-2.27), pre-KT CVD (HR, 4.87; 95% CI, 2.84-8.35), and age at KT ≥45 years (HR, 2.98; 95% CI, 1.83-4.87). In the model for pre-KT and post-KT variables together, the sole post-KT CVD predictor was estimated glomerular filtration rate <60 mL/min at the 6-month visit (HR, 1.75; 95% CI, 1.11-2.77). Diabetic nephropathy, pre-KT dialysis, pre-KT CVD, and age at KT predicted 91.2% of incident CVD. Early available information effectively predicted CVD in KT independently from competing events.


Asunto(s)
Enfermedades Cardiovasculares/epidemiología , Trasplante de Riñón/efectos adversos , Complicaciones Posoperatorias/epidemiología , Adulto , Factores de Edad , Anciano , Enfermedades Cardiovasculares/etiología , Trastornos Cerebrovasculares/epidemiología , Trastornos Cerebrovasculares/etiología , Estudios de Cohortes , Enfermedad Coronaria/epidemiología , Enfermedad Coronaria/etiología , Nefropatías Diabéticas/complicaciones , Nefropatías Diabéticas/epidemiología , Diálisis/efectos adversos , Femenino , Estudios de Seguimiento , Tasa de Filtración Glomerular , Humanos , Incidencia , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Enfermedad Arterial Periférica/epidemiología , Enfermedad Arterial Periférica/etiología , Complicaciones Posoperatorias/etiología , Periodo Preoperatorio , Modelos de Riesgos Proporcionales , Análisis de Regresión , Factores de Riesgo , Factores de Tiempo
3.
Neurobiol Dis ; 70: 117-26, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24969023

RESUMEN

In this study we show that postnatal development of cerebellar granule neurons (GNs) is defective in Npc1(-/-) mice. Compared to age-matched wild-type littermates, there is an accelerated disappearance of the external granule layer (EGL) in these mice. This is due to a premature exit from the cell cycle of GN precursors residing at the level of the EGL. As a consequence, the size of cerebellar lobules of these mice displays a 20%-25% reduction compared to that of age-matched wild-type mice. This size reduction is detectable at post-natal day 28 (PN28), when cerebellar GN development is completed while signs of neuronal atrophy are not yet apparent. Based on the analysis of EGL thickness and the determination of proliferating GN fractions at increasing developmental times (PN8-PN14), we trace the onset of this GN developmental defect during the second postnatal week. We also show that during this developmental time Shh transcripts undergo a significant reduction in Npc1(-/-) mice compared to age-matched wild-type mice. In light of the mitogenic activity of Shh on GNs, this observation further supports the presence of defective GN proliferation in Npc1(-/-) mice. A single injection of hydroxypropyl-ß-cyclodextrin at PN7 rescues this defect, restoring the normal patterns of granule neuron proliferation and cerebellar lobule size. To our knowledge, these findings identify a novel developmental defect that was underappreciated in previous studies. This defect was probably overlooked because Npc1 loss-of-function does not affect cerebellar foliation and causes the internal granule layer and molecular layer to decrease proportionally, giving rise to a normally appearing, yet harmoniously smaller, cerebellum.


Asunto(s)
Cerebelo/efectos de los fármacos , Cerebelo/crecimiento & desarrollo , Neuronas/efectos de los fármacos , Fármacos Neuroprotectores/farmacología , Proteínas/metabolismo , beta-Ciclodextrinas/farmacología , 2-Hidroxipropil-beta-Ciclodextrina , Animales , Apoptosis/efectos de los fármacos , Apoptosis/fisiología , Ciclo Celular/efectos de los fármacos , Ciclo Celular/fisiología , Cerebelo/fisiopatología , Proteínas Hedgehog/metabolismo , Péptidos y Proteínas de Señalización Intracelular , Ratones Endogámicos BALB C , Ratones Noqueados , Mitosis/efectos de los fármacos , Mitosis/fisiología , Neurogénesis/efectos de los fármacos , Neurogénesis/fisiología , Neuronas/fisiología , Proteína Niemann-Pick C1 , Tamaño de los Órganos , Proteínas/genética , ARN Mensajero/metabolismo
4.
Minerva Med ; 104(5): 505-17, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24101108

RESUMEN

AIM: The aim of the study was to investigate the effect of selective ETRA Sitaxsentan on viability and differentiation into myofibroblasts of lung fibroblasts derived from SSc-ILD patients and the ability of this drug to modify the lung fibroblast synthesis of VEGF, type I collagen and fibronectin. METHODS: Primary human lung fibroblast cultures were obtained from BAL of SSc-ILD patients. Cell cultures were exposed for 48 h to crescent concentrations of Sitaxsentan (10 -6M to 10 -4M). In these experimental conditions we evaluated cell viability through crystal violet staining, the production and mRNA expression of VEGF, fibronectin and type I collagen respectively through ELISA and real-Time PCR. Further, we detected alpha-Smooth Muscle Actin (α-SMA) through immunocytochemical assay. RESULTS: The lowest concentration of sitaxsentan (10-6M) did not affect fibroblasts viability; conversely at higher concentrations, sitaxsentan induced a significant inhibition of cell viability. Synthesis and mRNA expression of VEGF, type 1 collagen and fibronectin were significantly reduced in treated lung fibroblasts compared to the untreated ones, in a dose-dependent manner. At higher concentrations, Sitaxsentan reduced the expression of α-SMA. CONCLUSION: The results of this study show that sitaxentan is able in vitro to reduce both cell viability than production of VEGF and extra-cellular matrix components in SSc lung fibroblasts, confirming the anti-fibrotic potential of ETRA in SSc. The decreased expression of α-SMA in treated cells indicate that sitaxsentan may inhibit the fibroblast differentiation toward a myo-fibroblast phenotype and further support the hypothesis that the selective ETRAs may be beneficial in patients with SSc-ILD as anti fibrotic agents.


Asunto(s)
Antagonistas de los Receptores de Endotelina , Endotelinas/antagonistas & inhibidores , Fibroblastos/efectos de los fármacos , Isoxazoles/farmacología , Pulmón/citología , Esclerodermia Sistémica/patología , Tiofenos/farmacología , Actinas/metabolismo , Adulto , Anciano , Diferenciación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Colágeno Tipo I/biosíntesis , Femenino , Fibroblastos/citología , Fibroblastos/metabolismo , Fibronectinas/biosíntesis , Humanos , Masculino , Persona de Mediana Edad , Músculo Liso/metabolismo , Miofibroblastos/citología , Factor A de Crecimiento Endotelial Vascular/biosíntesis
5.
Vaccine ; 31(34): 3435-41, 2013 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-23398932

RESUMEN

Delivery of influenza vaccine using innovative approaches such as microneedles has been researched extensively in the past decade. In this study we present concentration followed by formulation and coating of monobulks from 2008/2009 seasonal vaccine on to 3M's solid microstructured transdermal system (sMTS) by a GMP-scalable process. The hemagglutinin (HA) in monobulks was concentrated by tangential flow filtration (TFF) to achieve HA concentrations as high as 20mg/ml. The stability of the coated antigens was evaluated by the functional assay, single radial immunodiffusion (SRID). The data generated show stability of the coated antigen upon storage at 4°C and room temperature in the presence of desiccant for at least 8 weeks. Freeze-thaw stability data indicate the stability of the coated antigen in stressed conditions. The vaccine coated microstructures were evaluated in vivo in a guinea pig model, and resulted in immune titers comparable to the traditional trivalent vaccine administered intramuscularly. The data presented indicate the potential use of the technology in delivery of influenza vaccine. This paper also addresses the key issues of stability of coated antigen, reproducibility and scalability of the processes used in preparation of influenza vaccine coated microneedle patches that are important in developing a successful product.


Asunto(s)
Vacunas contra la Influenza/administración & dosificación , Infecciones por Orthomyxoviridae/inmunología , Parche Transdérmico , Administración Cutánea , Animales , Anticuerpos Antivirales/sangre , Antígenos Virales/administración & dosificación , Antígenos Virales/inmunología , Estabilidad de Medicamentos , Femenino , Cobayas , Pruebas de Inhibición de Hemaglutinación , Glicoproteínas Hemaglutininas del Virus de la Influenza/administración & dosificación , Glicoproteínas Hemaglutininas del Virus de la Influenza/inmunología , Vacunas contra la Influenza/inmunología , Inyecciones Intramusculares , Ratones , Ratones Endogámicos BALB C , Infecciones por Orthomyxoviridae/prevención & control , Reproducibilidad de los Resultados , Vacunación/instrumentación , Vacunación/métodos , Vacunas de Subunidad/administración & dosificación , Vacunas de Subunidad/inmunología
6.
Nutr Metab Cardiovasc Dis ; 23(2): 94-101, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21924881

RESUMEN

BACKGROUND AND AIMS: Obesity-driven lipotoxicity is a risk factors for cardiovascular disease. The Farnesoid X Receptor (FXR) is a bile acids sensor and member of the nuclear receptor superfamily. Activation of FXR lowers plasma triacylglycerols and glucose levels through a mechanism that involves both the repression of key regulatory genes in the liver and the modulation of insulin sensitivity in peripheral tissues. In the present study we have investigated whether administering obese (fa/fa) Zucker rats, a genetic model of obesity associated with dyslipidemia and insulin resistance, with an FXR ligand protects against lipid-induced cardiomyopathy. METHODS AND RESULTS: FXR is expressed in neonatal cardiomyocytes and the treatment with FXR agonists, chenodeoxycholic acid (CDCA), and GW4064, increased the mRNA expression of FXR and its canonical target gene, the small heterodimer partner (SHP), as well as proliferator-activated receptor alpha PPARα, acyl-CoA oxidase (AOX) and pyruvate dehydrogenase kinase (PDK-4). Feeding obese fa/fa rats with CDCA, 12 weeks, reduced hyperinsulinemia and hyperlipidaemia. The histological-pathological analysis of hearts demonstrated that treatment with the FXR ligand reduced lipid heart content decreased the rate of apoptosis, fibrosis scores and restored heart insulin signalling. Chronic CDCA administration, in the heart, induced PPARα and PPARα-regulated genes involved in ß-oxidation. CONCLUSION: FXR agonism exerts beneficial effects in a genetic model of lipid-induced cardiomyopathy. The striking benefit of this therapy on cardiac function in this model warrants an effort to determine whether a counterpart of this activity translates in human settings.


Asunto(s)
Enfermedades Cardiovasculares/fisiopatología , Metabolismo de los Lípidos , Miocardio/metabolismo , Obesidad/fisiopatología , Receptores Citoplasmáticos y Nucleares/genética , Acil-CoA Oxidasa/genética , Acil-CoA Oxidasa/metabolismo , Animales , Apoptosis/efectos de los fármacos , Ácidos y Sales Biliares/metabolismo , Glucemia/análisis , Enfermedades Cardiovasculares/etiología , Ácido Quenodesoxicólico/farmacología , Dislipidemias/metabolismo , Dislipidemias/patología , Fibrosis/tratamiento farmacológico , Hiperinsulinismo/tratamiento farmacológico , Hiperlipidemias/tratamiento farmacológico , Resistencia a la Insulina , Isoxazoles/farmacología , Hígado/metabolismo , Obesidad/complicaciones , PPAR alfa/genética , PPAR alfa/metabolismo , Proteínas Serina-Treonina Quinasas/genética , Proteínas Serina-Treonina Quinasas/metabolismo , Piruvato Deshidrogenasa Quinasa Acetil-Transferidora , ARN Mensajero/genética , ARN Mensajero/metabolismo , Ratas , Ratas Zucker , Receptores Citoplasmáticos y Nucleares/agonistas , Receptores Citoplasmáticos y Nucleares/metabolismo , Factores de Riesgo , Triglicéridos/sangre
8.
Allergy ; 65(10): 1306-12, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20557302

RESUMEN

BACKGROUND: Female hormones play an important role in women's lung health, especially in asthma pathophysiology. Although a growing interest has recently been aroused in asthma related to short-term reproductive states, menopausal asthma has been little studied in the past. The aim of the present study was to explore airway inflammation in menopausal asthmatic women in a noninvasive manner. METHODS: Forty consecutive women with menopausal asthma, 35 consecutive women with premenopausal asthma and 30 age-matched healthy controls were enrolled in the study. Urinary LTE-4, induced sputum inflammatory cells, and exhaled LTE-4, IL-6, pH, and NO levels were measured in all the subjects enrolled. RESULTS: Women with menopausal asthma showed decreased estradiol concentrations, high sputum neutrophils, and exhaled IL-6. Women with premenopausal asthma presented instead an essentially eosinophilic inflammatory pattern. Higher urine and breath condensate LTE-4 concentrations were found in premenopausal and menopausal asthma compared to controls. CONCLUSION: Our results substantiate the existence of a new biological phenotype of menopausal asthma that is mainly characterized by neutrophilic airways inflammation and shares several characteristics of the severe asthma phenotype.


Asunto(s)
Asma , Menopausia , Asma/patología , Asma/fisiopatología , Estudios de Casos y Controles , Eosinófilos , Espiración , Femenino , Humanos , Concentración de Iones de Hidrógeno , Inflamación/patología , Interleucina-4/análisis , Leucotrieno E4/análisis , Leucotrieno E4/orina , Persona de Mediana Edad , Neutrófilos/patología , Óxido Nítrico/análisis , Fenotipo , Premenopausia , Esputo
9.
Mutagenesis ; 16(5): 395-400, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11507238

RESUMEN

Mouse erythroleukemia (Mel) cells have a cell cycle-dependent high sensitivity to chemical and physical mutagens. This report shows that a 5 h exposure to 0.1 or 0.01 microg/ml metavanadate during the initial period of erythroid differentiation induction was sufficient to permanently damage the ability of treated Mel cells and their progeny to undergo erythroid differentiation, without affecting cell viability and proliferation. Conversely, a 5 h pulse of metavanadate at 1 or 10 microg/ml inhibited both differentiation and cell proliferation. The cell cycle-dependent period of mutagenesis was essential for fixation of damage in the cell genome and the progeny of the cells treated with 0.1 or 0.01 microg/ml metavanadate stably inherited an impaired capacity to differentiate. The efficiency of the DNA repair synthesis machinery during the specific period of exposure of Mel cells seemed directly involved in damage fixation. In fact, the mutagenic effects of a 0.1 microg/ml metavanadate pulse was further increased in the presence of 1 mM hydroxyurea, an inhibitor of DNA repair synthesis. In contrast, 5 microg/ml vanillin, an antimutagenic agent that stimulates repair, completely restored the capacity of progeny of cells treated with 0.1 microg/ml metavanadate to complete differentiation. Determination of [(3)H]deoxythymidine in acid-insoluble DNA indicated that incorporation was stimulated by metavanadate alone and was further increased by metavanadate plus vanillin; conversely, incorporation of thymidine was reduced in the presence of hydroxyurea. The capacity of metavanadate to permanently damage Mel cell erythroid differentiation appeared to depend on the cell cycle-related efficiency of the DNA repair systems, activated to correct the induced alteration, rather than on a specific concentration.


Asunto(s)
Ciclo Celular/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Leucemia Eritroblástica Aguda/patología , Vanadatos/toxicidad , Animales , Reparación del ADN/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Virus de la Leucemia Murina de Friend , Leucemia Eritroblástica Aguda/genética , Leucemia Eritroblástica Aguda/metabolismo , Ratones , Células Tumorales Cultivadas
10.
J Virol ; 69(4): 2075-81, 1995 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-7884853

RESUMEN

The ability of monoclonal antibodies (MAbs) to passively cure an influenza virus pneumonia in the absence of endogenous T- and B-cell responses was investigated by treating C.B-17 mice, homozygous for the severe combined immunodeficiency (SCID) mutation, with individual monoclonal antiviral antibodies 1 day after pulmonary infection with influenza virus PR8 [A/PR/8/34 (H1N1)]. Less than 10% of untreated SCID mice survived the infection. By contrast, 100% of infected SCID mice that had been treated with a single intraperitoneal inoculation of at least 175 micrograms of a pool of virus-neutralizing (VN+) antihemagglutinin (anti-HA) MAbs survived, even if antibody treatment was delayed up to 7 days after infection. The use of individual MAbs showed that recovery could be achieved by VN+ anti-HA MAbs of the immunoglobulin G1 (IgG1), IgG2a, IgG2b, and IgG3 isotypes but not by VN+ anti-HA MAbs of the IgA and IgM isotypes, even if the latter were used in a chronic treatment protocol to compensate for their shorter half-lives in vivo. Both IgA and IgM, although ineffective therapeutically, protected against infection when given prophylactically, i.e., before exposure to virus. An Fc gamma-specific effector mechanism was not an absolute requirement for antibody-mediated recovery, as F(ab')2 preparations of IgGs could cure the disease, although with lesser efficacy, than intact IgG. An anti-M2 MAb of the IgG1 isotype, which was VN- but bound well to infected cells and inhibited virus growth in vitro, failed to cure. These observations are consistent with the idea that MAbs of the IgG isotype cure the disease by neutralizing all progeny virus until all productively infected host cells have died. VN+ MAbs of the IgA and IgM isotypes may be ineffective therapeutically because they do not have sufficient access to all tissue sites in which virus is produced during influenza virus pneumonia.


Asunto(s)
Anticuerpos Monoclonales/uso terapéutico , Inmunoglobulina G/uso terapéutico , Infecciones por Orthomyxoviridae/terapia , Neumonía Viral/terapia , Animales , Anticuerpos Monoclonales/administración & dosificación , Anticuerpos Monoclonales/inmunología , Hemaglutininas Virales/inmunología , Inmunoglobulina A/inmunología , Inmunoglobulina A/uso terapéutico , Fragmentos Fab de Inmunoglobulinas/inmunología , Fragmentos Fab de Inmunoglobulinas/uso terapéutico , Inmunoglobulina G/inmunología , Inmunoglobulina M/inmunología , Inmunoglobulina M/uso terapéutico , Inmunoterapia Adoptiva , Inyecciones Intraperitoneales , Ratones , Ratones SCID , Pruebas de Neutralización , Infecciones por Orthomyxoviridae/complicaciones , Neumonía Viral/complicaciones , Neumonía Viral/virología
11.
J Immunol ; 152(4): 1653-61, 1994 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-8120375

RESUMEN

Immunity that cross-reacts between influenza type A viruses of distinct subtypes is called hetero(sub)typic (Het-I). We have studied Het-I by challenging PR8-immune mice with the heterosubtypic virus X31. Het-I did not prevent infection by X31 but, at its height, strongly aided in recovery. The nature of the effector mechanisms involved was investigated by simultaneous challenge with X31 and an immunologically unrelated influenza type B virus and by depleting individual lymphocyte subsets in PR8-immune mice before challenge. The study showed the following: 1) The effector mechanisms were intimately associated with immune recognition events. 2) In the nose, depletion of CD8+ or CD4+ T cells led to partial reduction of Het-I, and simultaneous depletion of both T cell subsets abrogated Het-I almost completely. This T cell-mediated immunity was short lived and had disappeared 4 to 5 mo after induction. 3) In trachea and lung, depletion of CD8+ T cells led to a partial reduction of Het-I, whereas depletion of CD4+ T cells was without significant effect. The CD8-mediated component appeared short lived, whereas the residual immunity (in CD4/8-depleted mice) was long lived and persisted past 7 mos after induction. 4) Depletion of NK cells did not significantly reduce the strength of Het-I in either nose or lung. In conclusion, the study shows that Het-I in this system is mediated by a complex combination of immune mechanisms that differ, in part, between upper and lower respiratory tract.


Asunto(s)
Virus de la Influenza A/inmunología , Linfocitos T/inmunología , Animales , Antígenos CD4/fisiología , Antígenos CD8/fisiología , Femenino , Gangliósido G(M1)/inmunología , Depleción Linfocítica , Ratones , Ratones Endogámicos BALB C , Factores de Tiempo , Proteínas Virales/inmunología
12.
J Neurol Sci ; 115 Suppl: S24-8, 1993 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8340789

RESUMEN

Cytotoxic T lymphocytes (CTL) have long been recognized as playing a major role in the immune response to alloantigens and viral antigens as well as tumor antigens. The progress of the last decade in the identification and characterization of soluble factors involved in the regulation of the immune response has greatly improved our knowledge of the mechanisms of CTL activation and regulation. This review will summarize the data available in the literature regarding different lymphokines and their specific activity on CTL. In addition it will point out a few of the elements of the systems that hamper its full understanding and it will suggest possible directions for future research.


Asunto(s)
Linfocinas/fisiología , Linfocitos T Citotóxicos/citología , Animales , Diferenciación Celular , División Celular , Humanos , Activación de Linfocitos , Linfocitos T Citotóxicos/fisiología
13.
J Immunol ; 148(1): 212-7, 1992 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-1530795

RESUMEN

Intranasal exposure of athymic (nu/nu) BALB/c mice to influenza virus leads to a persistent infection of the respiratory tract from which the mice die, usually within 3 to 4 wk with symptoms of general cachexia. However, if these nude mice were injected 1 day after infection, with approximately 10(6) cells from individual virus-specific MHC class II-restricted Th cell clones, they showed greatly reduced mortality and the titers of infectious virus in their lungs were reduced, often to undetectable levels. By coinfecting mice with pairs of antigenically distinct viruses and subsequently determining the extent of clearance of each type of virus, it could be shown first that the clearance mechanism was immunologically specific but did not display the typical crossreaction of class I-restricted cytotoxic T (Tc) cells. In addition, neither primary nor memory Tc responses could be detected in these mice. Second, Th cell clones promoted clearance solely of those viruses that contained the specific Th cell determinant, i.e., Th cell-nonreactive bystander viruses were not cleared. These findings were compatible with virus clearance being effected either directly after recognition of infected class II-positive cells by the transferred Th cells or indirectly via promotion of a glycoprotein-specific antibody response. The latter seems to be the case because transfer of Th cells into infected T and B cell-deficient SCID mice did not result in virus clearance, although transfer of an anti-hemagglutinin antibody cocktail did. Thus, a virus-specific Tc cell response is not a requirement for recovery from a pulmonary influenza virus infection.


Asunto(s)
Infecciones por Orthomyxoviridae/inmunología , Linfocitos T Citotóxicos/inmunología , Linfocitos T Colaboradores-Inductores/inmunología , Animales , Anticuerpos Antivirales/inmunología , Antígenos Virales/inmunología , Citotoxicidad Inmunológica , Relación Dosis-Respuesta Inmunológica , Hemaglutininas Virales/inmunología , Antígenos de Histocompatibilidad Clase I/inmunología , Inmunidad Celular , Inmunización Pasiva , Virus de la Influenza A/inmunología , Enfermedades Pulmonares/inmunología , Complejo Mayor de Histocompatibilidad , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Ratones SCID/inmunología , Bazo/citología
14.
J Virol ; 65(11): 6071-6, 1991 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-1920626

RESUMEN

The activity of distinct CD4+ T-helper cell (Th) clones in promoting secondary A/PR/8/34/Mt.S.(H1N1) (A/PR8) influenza virus-specific, class I-restricted cytotoxic T-lymphocyte (CTL) responses in vitro was examined. CD8+ T cells which had been purified by fluorescence-activated cell sorter from spleen cells of A/PR8-primed mice were used as responders. On their own, purified CD8+ T cells were unable to generate cytotoxic activity upon in vitro culture with A/PR8-infected stimulator cells. Significant cytotoxic activity was generated in cultures that were additionally supplemented with A/PR8-specific Th clones or cell-free supernatant from these clones. Although there were large differences among individual Th clones in this function, Th clones of type 1 (Th1) promoted, on average, significantly stronger cytotoxic responses than Th clones of type 2 (Th2). The differences in promotion of a cytotoxic response correlated with the amount of interleukin-2 (IL-2) or IL-4 secreted by individual Th clones. These two lymphokines accounted for the CTL-promoting activity of the respective Th clones, since addition of recombinant IL-2 (IL-2) or rIL-4 to Th-free cultures substituted fully for the respective Th clones. As observed with Th clones, rIL-2 was significantly more effective than rIL-4 in promoting a cytotoxic response. When used in combination, Th2 clones had an antagonistic effect on the generation of a CTL response by Th1 clones. This effect could be partially transferred with cell-free supernatant from activated Th2 clones and could be reversed by addition of excess rIL-2. Both consumption of IL-2 by Th2 and secretion of an inhibitory factor(s) appear to be involved in this phenomenon.


Asunto(s)
Antígenos CD4/inmunología , Citotoxicidad Inmunológica , Virus de la Influenza A/inmunología , Virus de la Influenza B/inmunología , Subgrupos de Linfocitos T/inmunología , Linfocitos T Citotóxicos/inmunología , Animales , Antígenos CD8/inmunología , Células Cultivadas , Embrión de Pollo , Células Clonales , Interleucina-2/análisis , Interleucina-2/biosíntesis , Interleucina-4/análisis , Interleucina-4/biosíntesis , Cinética , Ratones , Ratones Endogámicos BALB C , Bazo/inmunología
15.
J Virol ; 65(1): 364-72, 1991 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-1702160

RESUMEN

Eight nonoverlapping regions of the hemagglutinin (HA) molecule of influenza virus A/PR/8/34 (PR8), which serve as recognition sites for class II-restricted T cells (TH) from BALB/c mice, have been identified in the form of 10- to 15-amino-acid-long synthetic peptides. These TH determinants are located between residues 110 to 313 of the HA1 polypeptide. From a total of 36 HA-specific TH clones and limiting-dilution cultures of independent clonal origins, 33 (90%) responded to stimulation with one of these peptides. The residual three TH clones appeared to recognize a single additional determinant on the HA1 polypeptide which could not be isolated, however, in the form of a stimulatory peptide. None of the motifs that have been proposed to typify TH determinants were displayed by more than half of these recognition sites. Most unexpected was the finding that none of the TH determinants was located in the ectodomain of the HA2 polypeptide that makes up roughly one-third of the HA molecule. Possible reasons for the preferential recognition of HA1 as opposed to HA2 by TH are discussed.


Asunto(s)
Epítopos/inmunología , Hemaglutininas Virales/inmunología , Antígenos de Histocompatibilidad Clase II/inmunología , Subtipo H1N1 del Virus de la Influenza A , Virus de la Influenza A/inmunología , Linfocitos T/inmunología , Secuencia de Aminoácidos , Animales , Antígenos Virales/inmunología , Células Cultivadas , Células Clonales , Femenino , Glicoproteínas Hemaglutininas del Virus de la Influenza , Hemaglutininas Virales/genética , Inmunización , Ratones , Ratones Endogámicos BALB C , Modelos Moleculares , Datos de Secuencia Molecular , Conformación Proteica , Homología de Secuencia de Ácido Nucleico
16.
Cancer Res ; 50(17): 5438-45, 1990 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-2386948

RESUMEN

Hemoglobin adducts of the carcinogenic tobacco-specific nitrosamines 4-(methylnitrosamino)-1(3-pyridyl)-1-butanone and N'-nitrosonornicotine were quantified in blood samples collected from snuff dippers, smokers, and nonsmokers. Mild base treatment of hemoglobin adducted by 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone or N'-nitrosonornicotine releases 4-hydroxy-1-(3-pyridyl)-1-butanone (HPB). HPB was enriched by solvent partitioning and derivatized to its pentafluorobenzoate. After purification by high performance liquid chromatography, HPB-pentafluorobenzoate was analyzed by capillary column gas chromatography with detection by negative ion chemical ionization mass spectrometry and selected ion monitoring. [4,4-D2]HPB was used as internal standard. The detection limit for HPB-pentafluorobenzoate was approximately 100 amol/injection or 5 fmol/g hemoglobin. Mean adduct levels (fmol HPB/g hemoglobin) were 517 +/- 538 (SD) in snuff dippers, 79.6 +/- 189 in smokers, and 29.3 +/- 25.9 in nonsmokers. Adduct levels in snuff dippers and in a subgroup of smokers were higher than would have been predicted solely based on estimates of exposure to tobacco-specific nitrosamines. The results of this study provide the first measurements of tobacco-specific nitrosamine hemoglobin adducts in humans and suggest new approaches to understanding the metabolic activation of 4-(methyl-nitrosamino)-1-(3-pyridyl)-1-butanone and N'-nitrosonornicotine in humans.


Asunto(s)
Carcinógenos/análisis , Hemoglobinas/metabolismo , Nicotiana , Nitrosaminas/análisis , Plantas Tóxicas , Fumar/sangre , Tabaco sin Humo , Adulto , Cotinina/sangre , Femenino , Cromatografía de Gases y Espectrometría de Masas/métodos , Humanos , Masculino
17.
J Trauma ; 28(3): 347-52, 1988 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-2832618

RESUMEN

Cats were subjected to a 3.5-atm fluid percussion impact administered to the cerebral cortex. Near-infrared spectrophotometry (NIRS) was used to measure the quantity of oxyhemoglobin and total hemoglobin in the illuminated tissue as well as the cytochrome a, a3 redox state. Corroborative data were obtained by freezing brains with liquid nitrogen and measuring cortical concentrations of ATP, creatine phosphate (CP), and lactate. Immediately postimpact there was a rise in mean arterial pressure with a 38% increase of highly oxygenated blood and a shift toward oxidation in the cytochrome a, a3 redox state. By 4 hours postimpact, cytochrome a, a3 was becoming progressively reduced despite the persistence of hyperemia. This was associated with a significant (p less than 0.01) decrease in ATP and CP concentration. Additional studies in which a 0.5-sec, 100-v electrical seizure was induced before and after fluid percussion demonstrated significant differences in seizure response, indicating a failure of autoregulation.


Asunto(s)
Química Encefálica , Lesiones Encefálicas/metabolismo , Homeostasis , Adenosina Trifosfato/análisis , Animales , Gatos , Complejo IV de Transporte de Electrones/análisis , Hemoglobinas/análisis , Lactatos/análisis , Oxidación-Reducción , Oxihemoglobinas/análisis , Fosfocreatina/análisis , Convulsiones/metabolismo , Espectrofotometría Infrarroja
19.
J Trauma ; 26(10): 863-8, 1986 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-3021965

RESUMEN

Intracranial pressure was increased in cats by infusing 'mock' CSF intracranially, thus decreasing cerebral perfusion and oxygenation. The cats then randomly received either 50% O2 or 50% O2-5% CO2 by inhalation. As monitored by in vivo near-infrared spectroscopy (NIR), no improvement was noted after 50% O2 whereas 50% O2-5% CO2 resulted in increased perfusion, an oxidation of cytochrome a,a3, an increase in oxyhemoglobin, and reduced quantities of de-oxyhemoglobin (p less than 0.01) despite a further increase in intracranial pressure. The authors conclude that: NIR is a useful means of noninvasively and directly assessing brain metabolism and has advantages over simple ICP monitoring; and continued investigations of CO2 as a possible therapeutic modality after head injury appear warranted.


Asunto(s)
Encéfalo/metabolismo , Presión Intracraneal , Animales , Dióxido de Carbono/administración & dosificación , Gatos , Circulación Cerebrovascular , Complejo IV de Transporte de Electrones/metabolismo , Femenino , Hemoglobinas/metabolismo , Monitoreo Fisiológico/métodos , Oxígeno/administración & dosificación , Consumo de Oxígeno , Oxihemoglobinas/metabolismo , Espectrofotometría Infrarroja
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