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1.
J Sports Sci ; 42(7): 559-565, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38734977

RESUMEN

Modern technology challenges anecdotal beliefs on baseball performance. The study's purpose examines these beliefs by classifying batted ball outcomes. Three categories of independent variables (anthropometry, in-game situation, technique-based), from 1,922 batted ball outcomes produced by 230 players, were used to classify the likelihood of hits during 2021 college baseball games. Anthropometry included player's heights and weights. In-game situation entailed batter side, same side, ahead count, and pitch type. Technique-based variables measured by TrackMan radar included exit speed (ExSp), launch angle (LA), batted ball distance (BBD), and hang time (HT). Binary logistic regression analysis was performed with batted ball outcome as the dependent variable. Independent variables provided a good fit (χ2 (10) = 522.358, p < 0.01) and correctly classified nearly three-fourths of outcomes. Height (ß = 0.030, p < 0.05), ExSp (ß = 0.023, p < 0.05), LA (ß = 0.028, p < 0.01), and BBD (ß = 0.067, p < 0.01) each had significant positive associations, yet HT (ß = -1.661, p < 0.01) had a significant negative association, with batted ball outcomes. TrackMan provided four significant independent variables. Anthropometry's contribution to batting outcome was modest, while in-game situation's impact was non-significant; results contradict anecdotal beliefs of their importance.


Asunto(s)
Antropometría , Rendimiento Atlético , Béisbol , Humanos , Rendimiento Atlético/clasificación , Rendimiento Atlético/fisiología , Adulto Joven , Masculino , Destreza Motora/fisiología , Destreza Motora/clasificación
2.
J Natl Cancer Inst ; 66(2): 249-54, 1981 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-6935475

RESUMEN

Antibody directed against a cultured melanoma cell line known to express an oncofetal antigen was measured in sera obtained from patients with stage II melanomas. This study was undertaken to determine if an inhibiting or enhancing effect on tumor growth would be suggested by a positive or negative correlation of antibody levels with tumor recurrence or patient survival. A positive correlation with disease-free interval and survival was detected among patients who had high levels of the IgM class of antibody before and shortly after surgery for state II disease. The IgG class of antibody over the period measured did not correlate consistently with tumor recurrence. Absorption of the IgM antibody with fetal brain confirmed that the dominant detectable reactivity was directed to the oncofetal antigen. The relevance of these findings is related to that of other evidence indicating that immunity to fetal antigens expressed on tumor cells is a participant in host-tumor interaction.


Asunto(s)
Anticuerpos Antineoplásicos/análisis , Antígenos de Neoplasias/inmunología , Inmunoglobulina M/análisis , Melanoma/inmunología , Células Cultivadas , Feto/inmunología , Humanos , Metástasis Linfática , Melanoma/mortalidad , Melanoma/cirugía , Recurrencia , Factores de Tiempo
3.
Biochim Biophys Acta ; 1458(2-3): 387-403, 2000 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-10838053

RESUMEN

F(1)F(0) ATP synthases are known to synthesize ATP by rotary catalysis in the F(1) sector of the enzyme. Proton translocation through the F(0) membrane sector is now proposed to drive rotation of an oligomer of c subunits, which in turn drives rotation of subunit gamma in F(1). The primary emphasis of this review will be on recent work from our laboratory on the structural organization of F(0), which proves to be consistent with the concept of a c(12) oligomeric rotor. From the NMR structure of subunit c and cross-linking studies, we can now suggest a detailed model for the organization of the c(12) oligomer in F(0) and some of the transmembrane interactions with subunits a and b. The structural model indicates that the H(+)-carrying carboxyl of subunit c is located between subunits of the c(12) oligomer and that two c subunits pack in a front-to-back manner to form the proton (cation) binding site. The proton carrying Asp61 side chain is occluded between subunits and access to it, for protonation and deprotonation via alternate entrance and exit half-channels, requires a swiveled opening of the packed c subunits and stepwise association with different transmembrane helices of subunit a. We suggest how some of the structural information can be incorporated into models of rotary movement of the c(12) oligomer during coupled synthesis of ATP in the F(1) portion of the molecule.


Asunto(s)
Escherichia coli/enzimología , Proteínas Motoras Moleculares/química , ATPasas de Translocación de Protón/química , Adenosina Trifosfato/biosíntesis , Proteínas Bacterianas/química , Sitios de Unión , Espectroscopía de Resonancia Magnética , Proteínas de la Membrana/química , Modelos Moleculares , Propionibacterium/enzimología , Conformación Proteica , Pliegue de Proteína
4.
Biochim Biophys Acta ; 1365(1-2): 135-42, 1998 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-9693732

RESUMEN

In this review, we summarize recent work from our laboratory which establishes the topology and nearest neighbor organization of subunits in the F0 sector of the H+ transporting ATP synthase of Escherichia coli. The E. coli F0 sector is composed of three subunits in an a1b2c12 stoichiometric ratio. Crosslinking experiments with genetically introduced Cys establish a ring-like organization of the 12 c subunits with subunits a and b lying to the outside of the ring. The results are interpreted using an atomic resolution structural model of monomeric subunit c in a chloroform-methanol-water (4:4:1, v/v/v) solution, derived by heteronuclear NMR (M.E. Girvin, F. Abildgaard, V. Rastogi, J. Markley, R.H. Fillingame, in press). The crosslinking results validate many predictions of the structural model and confirm a front-to-back-type packing of two subunit c into a functional dimer, as was first predicted from genetic studies. Aspartyl-61, the proton translocating residue, lies at the center of the four transmembrane helices of the functional dimer, rather than at the periphery of the subunit c ring. Subunit a is shown to fold with five transmembrane helices, and a functionally important interaction of transmembrane helix-4 with transmembrane helix-2 of subunit c is established. The single transmembrane helices of the two subunit b dimerize in the membrane. The structure of the transmembrane segment of subunit b is predicted from the NMR structure of the monomeric peptide.


Asunto(s)
Escherichia coli/enzimología , ATPasas de Translocación de Protón/química , Dimerización , Espectroscopía de Resonancia Magnética , Modelos Moleculares , Conformación Proteica , Pliegue de Proteína , Relación Estructura-Actividad
5.
FEBS Lett ; 494(1-2): 1-5, 2001 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-11297723

RESUMEN

In recent years, structural information on the F(1) sector of the ATP synthase has provided an insight into the molecular mechanism of ATP catalysis. The structure strongly supports the proposal that the ATP synthase works as a rotary molecular motor. Insights into the membrane domain have just started to emerge but more detailed structural information is needed if the molecular mechanism of proton translocation coupled to ATP synthesis is to be understood. This review will focus mainly on the ion translocating rotor in the membrane domain of the F-type ATPase, and the related vacuolar and archaeal relatives.


Asunto(s)
ATPasas de Translocación de Protón Mitocondriales , ATPasas de Translocación de Protón/química , ATPasas de Translocación de Protón Vacuolares , Adenosina Trifosfato , Secuencia de Aminoácidos , Animales , Cloroplastos/enzimología , Humanos , Hidrógeno , Iones , Datos de Secuencia Molecular , Saccharomyces cerevisiae/enzimología
6.
Surgery ; 92(2): 362-7, 1982 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-7101129

RESUMEN

Since September 1979, 44 stage III melanoma patients treated with intralymphatic immunotherapy (ILI) with an oncofetal antigen (OFA-I)--enriched tumor cell vaccine (TCV) had evaluable humoral immune responses and clinical follow-up. Fourteen patients (32%) had stabilization or regression of tumors or remained free of resected disease. The median survival was 17 months, compared with 6 months for controls (P less than 0.001). Humoral immune responses were monitored by immune adherence using an OFA-positive human melanoma cell line, M14, as target. Alloantibodies were removed by absorption with L14 lymphoblasts autologous to M14. Twenty-two patients (50%) developed elevated antibody titers within 4 months, and 12 of the 22 (55%) had no disease progression. In contrast, 20 of 22 patients (91%) who failed to develop elevated titers had disease progression (P less than 0.01). The median titer was significantly higher during the first 4 months in the group whose disease did not progress (P less than 0.04). This study demonstrated that ILI with allogeneic OFA-I-enriched TCV can induce objective tumor regression and prolonged survival in patients with disseminated melanoma. Furthermore, because the specific humoral immune response correlates with clinical results, immunization efficacy can be monitored within a short period of time, which should aid future efforts to achieve optimal immunotherapy.


Asunto(s)
Formación de Anticuerpos , Antígenos de Neoplasias/uso terapéutico , Inmunoterapia , Melanoma/terapia , Neoplasias Cutáneas/terapia , Adulto , Anciano , Antígenos de Neoplasias/inmunología , Femenino , Humanos , Inmunoglobulina M/análisis , Masculino , Melanoma/inmunología , Persona de Mediana Edad , Neoplasias Cutáneas/inmunología , Vacunas/inmunología
7.
Arch Surg ; 112(6): 742-4, 1977 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-860923

RESUMEN

Many articles published in the medical literature have stated that a normal-appearing appendix as seen via contrast enema is inconsistent with the diagnosis of acute appendicitis. This assumes that appendicitis is always associated with complete luminal obstruction of the appendix, and that the length of the normal appendix is known to the interpreter of the x-ray examination. Retrospective analysis of the barium contrast studies of three patients found to have acute appendicitis demonstrated the limitations of this hypothesis. These patients were diagnosed as having acute appendicitis at operation in spite of radiologic evidence of normal-appearing appendices. We review radiologic findings that can be helpful in recognizing this condition and discuss the severe limitations of barium contrast studies in making an accurate diagnosis.


Asunto(s)
Apendicitis/diagnóstico por imagen , Absceso/cirugía , Enfermedad Aguda , Adolescente , Apendicectomía , Apendicitis/cirugía , Errores Diagnósticos , Femenino , Humanos , Perforación Intestinal/cirugía , Masculino , Persona de Mediana Edad , Radiografía
8.
J Dent Res ; 66(2): 436-41, 1987 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-3305626

RESUMEN

The protective functions of saliva are attributed, in part, to its serous and mucous glycoproteins. We have studied, as representative molecules, the proline-rich glycoprotein (PRG) from human parotid saliva and the high (MG1) and low (MG2) molecular weight mucins from submandibular-sublingual saliva. PRG (38.9 kDa) contains 40% carbohydrate consisting of 6 triantennary N-linked units and a single peptide chain of 231 amino acids, 75% of which = PRO + GLY + GLN. PRG's secondary structure is comprised of 70% random coil (naked regions) and 30% beta-turns (glycosylated domains). MG1 (greater than 10(3) kDa) contains 15% protein (several disulfide linked subunits), 78% carbohydrate (290 units of 4-16 residues), 7% sulfate, and small amounts of covalently linked fatty acids. MG2 (200-250 kDa) contains 30% protein (single peptide chain), 68% carbohydrate (170 units of 2-7 residues), and 2% sulfate. The major carbohydrate units of MG2 are: NeuAc alpha 2,3Gal beta 1,3GalNAc,Gal beta 1,3GalNAc, and Fuc alpha 1,2Gal beta 1,3GalNAc. MG1 contains hydrophobic domains, as evidenced by its ability to bind fluorescent hydrophobic probes; MG2 does not. Collectively, the biochemical and biophysical comparisons between MG1 and MG2 indicate that these two mucins are structurally different. Several functional properties of MG1, MG2, and PRG have been examined, including their presence in two-hour in vivo enamel pellicle, binding to synthetic hydroxyapatite, lubricating properties, and interactions with oral streptococci. The data presented suggest that these glycoproteins may have multiple functions which are predicated, in part on their carbohydrate units. The potential significance of the structure-function relationships of these glycoproteins to the oral ecology is discussed.


Asunto(s)
Glicoproteínas/clasificación , Proteínas y Péptidos Salivales/clasificación , Película Dental , Glicoproteínas/fisiología , Humanos , Mucinas/fisiología , Péptidos/fisiología , Dominios Proteicos Ricos en Prolina , Proteínas y Péptidos Salivales/fisiología , Relación Estructura-Actividad
9.
Respir Med ; 85(4): 281-4, 1991 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-1835110

RESUMEN

The role of short-term tests of reversibility in selecting patients with COAD for long-term nebuliser therapy is uncertain. In a double-blind placebo-controlled crossover study we have examined the correlation between short-term reversibility and response to a home nebuliser. We studied 20 patients with severe COAD (mean age 66, mean FEV1 0.81 l) and little reversibility (less than 20% increase in FEV1 post-inhaled salbutamol 200 micrograms and less than 25% increase in peak expiratory flow rate, PEFR, on oral steroids). PEFR, spirometry, lung volumes and airways conductance were recorded before and 1 h after a mixture of nebulised ipratropium 0.5 mg and fenoterol 1.25 mg. Patients then recorded twice-daily PEFR at home while they received nebulised ipratropium plus fenoterol, or saline placebo, four times a day for three week blocks using a double-blind cross over protocol. Mean PEFR on home nebuliser rose from 164 l m-1 (placebo) to 196 l m-1 (ipratropium plus fenoterol), paired t-test P = 0.0001. Correlation coefficients between short-term response for PEFR, spirometry and lung volumes, and improvement in home PEFR on nebulised ipratropium plus fenoterol, were all poor (R = -0.37-0.35, P = 0.83-0.11). We conclude that in severe COAD, reversibility tests of PEFR, spirometry and lung volumes do not correlate with response to a home nebuliser. Home measurements of PEFR are probably the best objective method of assessing response to a home nebuliser in such patients.


Asunto(s)
Fenoterol/administración & dosificación , Ipratropio/administración & dosificación , Enfermedades Pulmonares Obstructivas/tratamiento farmacológico , Anciano , Anciano de 80 o más Años , Enfermedad Crónica , Método Doble Ciego , Quimioterapia Combinada , Femenino , Humanos , Pulmón/fisiopatología , Enfermedades Pulmonares Obstructivas/fisiopatología , Mediciones del Volumen Pulmonar , Masculino , Persona de Mediana Edad , Nebulizadores y Vaporizadores , Ápice del Flujo Espiratorio/efectos de los fármacos , Espirometría
10.
Arch Oral Biol ; 36(5): 347-56, 1991.
Artículo en Inglés | MEDLINE | ID: mdl-1872731

RESUMEN

The purposes of this study were to examine the immunogenicity of the low molecular weight human salivary mucin (MG2) and determine its distribution within major and minor human salivary glands. Anti-MG2 sera were produced in Balb/c mice by a variety of immunization schedules. Chromatographically or electrophoretically purified MG2 and partially purified mucin chromatographic fractions exposed to mild denaturing conditions were not immunogenic. Only MG2 without prior exposure to urea or guanidine was able to elicit an immune response. A murine anti-MG2 monoclonal antibody (clone 1/F9) was produced and its monospecificity confirmed by immuno-dot blotting and SDS-PAGE Western transfer. Clone 1/F9 (IgG1; kappa) was of moderate affinity and was directed to a Pronase- and TPCK trypsin-sensitive but periodate-resistant epitope which was not blood group- or sialic acid-specific. Immunocytochemical studies of frozen tissue sections with clone 1/F9 using both indirect and direct methods revealed that MG2 was more heterogeneously distributed within submandibular than labial glands and was not found in parotid or palatine glands. The use of a polyclonal rabbit anti-MG2 reagent in either frozen or paraffin-embedded tissues gave the same immunocytochemical results as those obtained with the monoclonal antibody.


Asunto(s)
Mucinas/inmunología , Proteínas y Péptidos Salivales/inmunología , Adulto , Anciano , Animales , Anticuerpos Monoclonales , Formación de Anticuerpos , Antígenos , Western Blotting , Electroforesis en Gel de Poliacrilamida , Femenino , Humanos , Inmunización , Inmunohistoquímica , Masculino , Ratones , Ratones Endogámicos BALB C , Peso Molecular , Mucinas/análisis , Conejos , Proteínas y Péptidos Salivales/análisis , Glándula Submandibular/química , Glándula Submandibular/patología
11.
Arch Oral Biol ; 35(2): 127-36, 1990.
Artículo en Inglés | MEDLINE | ID: mdl-2188637

RESUMEN

The purpose of this study was to determine the distribution of mucin glycoprotein 1 (MG1) within submandibular, parotid, labial and palatine salivary tissues. Formalin-fixed and frozen tissue sections were examined histochemically with PAS, Alcian blue and Meyer's mucicarmine, and immunocytochemically with an anti-mucin glycoprotein 1 monoclonal antibody (clone 3/E8). Clone 3/E8 was produced in Balb/c mice using mucin-enriched chromatographic fractions from submandibular-sublingual saliva. The monospecificity of 3/E8 was confirmed by immuno-dot blotting and SDS-PAGE/electrophoretic transfer. Clone 3/E8 (IgG1; kappa) was of moderate affinity, and was directed to a carbohydrate-containing, TPCK-trypsin-insensitive and pronase-insensitive epitope on this mucin, which was not blood-group specific. The location of mucin glycoprotein 1 was determined by both indirect (peroxidase-antiperoxidase) and direct methods. Mucin glycoprotein 1 was localized within all labial acini examined, but was not found within parotid tissues. Histochemical methods stained all submandibular, palatine and labial acini, but immunocytochemistry with monoclonal antibody revealed heterogeneous staining with clone 3/E8 in submandibular and palatine tissues. These findings suggest the presence of mucin glycoprotein 1-specific acinar cell subpopulations within human submandibular and palatine salivary tissues.


Asunto(s)
Mucinas/metabolismo , Glándulas Salivales/metabolismo , Proteínas y Péptidos Salivales/metabolismo , Anciano , Humanos , Técnicas para Inmunoenzimas , Masculino , Peso Molecular , Glándulas Salivales Menores/metabolismo , Glándula Submandibular/metabolismo
12.
Artif Intell Med ; 12(2): 137-51, 1998 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9520221

RESUMEN

Using cognitive evaluation techniques, this study examines the effects of an electronic patient record and electronic mail on the interactions of health care providers. We find that the least structured communication methods are also the most heavily used: face-to-face, telephone, and electronic mail. Positive benefits of electronically-mediated interactions include improving communication, collaboration, and access to information to support decision-making. Negative factors include the potential for overloading clinicians with unwanted or unnecessary communications.


Asunto(s)
Redes de Comunicación de Computadores , Conducta Cooperativa , Personal de Salud , Comunicación , Humanos , Sistemas de Registros Médicos Computarizados , Relaciones Médico-Paciente
13.
Res Vet Sci ; 41(3): 378-82, 1986 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-3027800

RESUMEN

More than 300 bovine sera from a previously reported vaccination and challenge trial were tested for antibodies to bovine herpesvirus 1 (BHV1) by five serological assays: enzyme-linked immunosorbent assay (ELISA) for IgM and IgG, passive haemagglutination (PHA), and two methods of virus neutralisation (VN). In a statistical comparison of ELISA (IgG), PHA and VN results, the assays showed highly significant correlations (P less than 0.01). The sensitivities of ELISA and 24-hour neutralisation tests were similar, in contrast to passive haemagglutination and one hour neutralisation which failed to detect BHV1 antibodies in some low titre sera.


Asunto(s)
Anticuerpos Antivirales/inmunología , Herpesvirus Bovino 1/inmunología , Rinotraqueítis Infecciosa Bovina/inmunología , Vacunación/veterinaria , Animales , Bovinos , Ensayo de Inmunoadsorción Enzimática , Estudios de Evaluación como Asunto , Pruebas de Hemaglutinación/veterinaria , Pruebas de Neutralización
14.
Vet Rec ; 119(13): 319-21, 1986 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-3535230

RESUMEN

High milk yield, low milk fat and low milk protein were considered as possible predisposing factors to bovine Escherichia coli mastitis. Morning and afternoon milk yields were recorded in 46 Friesian cows later developing E coli mastitis and compared with 92 uninfected controls. Animals developing E coli mastitis gave a significantly higher milk yield than controls. The overall morning: afternoon ratio was (mean +/- se) 1.66 +/- 0.41, with no difference in ratio for the two groups. Further studies on 85 animals later developing E coli mastitis, and 192 controls, in four Friesian herds did not reveal differences in milk fat content (except as related to yield), milk protein or in the interrelationship of days of lactation, milk protein or in the interrelationship of days of lactation, milk fat and milk protein in the two groups. Again there was a correlation between high milk yield and a tendency to develop E coli mastitis but this may have been an age effect in both investigations. No correlation between milk yield and mastitis severity was detected. High yielders which succumbed to E coli mastitis in three herds were producing less milk than mastitis-free controls in the fourth herd which suggests that the correlation is not with yield per se.


Asunto(s)
Infecciones por Escherichia coli/veterinaria , Lactancia/fisiología , Mastitis Bovina/etiología , Leche/análisis , Animales , Bovinos , Enfermedades de los Bovinos/etiología , Infecciones por Escherichia coli/etiología , Femenino , Lípidos/análisis , Proteínas de la Leche/análisis , Embarazo
15.
Vet Rec ; 121(11): 256-8, 1987 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-3686786

RESUMEN

The results of 7569 inseminations performed on 6007 cows in 94 dairy herds were used to investigate the relative importance of time of insemination, bull and inseminator on calving rates in dairy cows. Although the time of insemination in relation to the first observation of oestrus was shown to have some effect, the effect was minimal during the first 24 hours. The maximum difference in expected calving rates between cows served with semen from groups of bulls with a history of either low or high fertility was 20 per cent, and the maximum difference in expected calving rate between cows inseminated by groups of inseminators who had consistently achieved either low or high fertility was 13 per cent.


Asunto(s)
Bovinos/fisiología , Estro/fisiología , Fertilidad , Inseminación Artificial/veterinaria , Preñez/fisiología , Animales , Femenino , Masculino , Modelos Biológicos , Embarazo , Factores de Tiempo
16.
Vet Rec ; 119(24): 593-5, 1986 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-3811175

RESUMEN

Analysis of more than 2000 bovine serum samples showed a large monthly variation in copper levels. There was also a difference in levels between beef and dairy cows although all showed the same monthly pattern. This monthly variation was correlated with rainfall; the higher the rainfall the lower the copper level. The interpretation of single herd blood copper values must be considered carefully in view of this variation.


Asunto(s)
Bovinos/sangre , Cobre/sangre , Animales , Inglaterra , Fenómenos Geológicos , Geología , Lluvia , Suelo
17.
Vet Rec ; 126(12): 279-84, 1990 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-2343510

RESUMEN

Jersey cows from several herds provided 97 fetuses and 24 calves at fixed gestational intervals between 80 and 290 days after conception. The fetuses and calves were killed, weighed and measured and, after dissection, the sizes and weights of a range of skeletal and soft tissues were recorded. Six morphological measurements emerged as most suitable for the determination of developmental age in the normal fetus. By plotting their mean values and 95 per cent tolerance limits, the rates of growth and the variability of each measurement were defined. Long bone length was the most useful single measurement for predicting the developmental age of the fetus. Brain weight, bodyweight, crown-anus length and long bone length showed curvilinear growth patterns; age prediction equations derived from these measurements are complicated to use and additional simplified formulae have been derived. The number of appendicular ossification centres also had predictive value, but it could not be used to determine fetal developmental age between 100 and 160 days gestation.


Asunto(s)
Animales Recién Nacidos/anatomía & histología , Bovinos/anatomía & histología , Bovinos/embriología , Feto/anatomía & histología , Edad Gestacional , Animales , Peso Corporal , Huesos/anatomía & histología , Huesos/embriología , Encéfalo/anatomía & histología , Encéfalo/embriología , Miembro Anterior/anatomía & histología , Miembro Anterior/embriología , Miembro Posterior/anatomía & histología , Miembro Posterior/embriología , Tamaño de los Órganos , Análisis de Regresión
18.
Vet Rec ; 118(25): 685-7, 1986 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-3739177

RESUMEN

In the autumn and winter of 1979 and the spring and summer of 1980 serum samples were taken from approximately 20 sows at between 40 and 90 days of gestation in each of seven commercial herds. In most of these herds progesterone concentrations were significantly lower in the autumn than in the other three seasons. Between June 1980 and June 1981 every pregnant sow in a further herd of 250 sows was sampled at 25 to 30 days and at 70 to 91 days of gestation. Seasonal differences in progesterone concentrations were again evident, with the concentrations rising from their lowest in August, September and October to a peak in March. Comparisons between the early and late pregnancy progesterone levels from sows sampled in this herd at different times of the year suggested that corpora lutea which were formed in the summer and early autumn were fully competent and responsive, but that their lower hormone production was possibly the result of reduced luteotrophic stimulation. These findings are pertinent to the pathophysiology of the autumn abortion syndrome and other seasonal reproductive problems in sows.


Asunto(s)
Preñez , Progesterona/sangre , Porcinos/sangre , Animales , Femenino , Embarazo , Estaciones del Año
19.
Vet Rec ; 120(20): 475-8, 1987 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-3603999

RESUMEN

Two sows which had been vaccinated with an oil-emulsion porcine parvovirus vaccine, and had developed high haemagglutination-inhibiting antibody levels to the virus, farrowed three successive litters each, a total of 74 piglets. Serum samples from these piglets were tested for haemagglutination-inhibiting antibody at birth, three and 17 days after birth, and at monthly intervals thereafter to study the decline of maternally-derived antibody. Regression curves were constructed from the data to show the projected pathway (mean and 95 per cent tolerance limits) of the decline of maternally-derived antibody. Approximately half the pigs still had positive titres of up to 1/160 at six months old, and traces of antibody were detected in a few pigs at nine months. Thus, even at the onset of breeding some gilts can have maternally-derived antibody which may interfere with their ability to develop active immunity to porcine parvovirus. From the same litters three groups of 12 pigs were selected randomly and were vaccinated with a single dose of the oil-emulsion vaccine at 70 days, 130 days or 190 days respectively. Despite the presence of moderate to high titres of maternally-derived antibody, especially in the younger pigs, all of those vaccinated showed strong and long lasting antibody responses to the vaccine. High serum antibody titres at the time of vaccination seemed to depress the response to the vaccine slightly but the effect was not statistically significant. These results have important implications for prevention of reproductive failure induced by porcine parvovirus.


Asunto(s)
Anticuerpos Antivirales/análisis , Inmunidad Materno-Adquirida , Parvoviridae/inmunología , Porcinos/inmunología , Vacunas Virales/inmunología , Animales , Animales Recién Nacidos , Anticuerpos Antivirales/biosíntesis , Femenino , Pruebas de Inhibición de Hemaglutinación , Análisis de Regresión , Vacunación/veterinaria
20.
Pediatr Dent ; 13(3): 142-50, 1991.
Artículo en Inglés | MEDLINE | ID: mdl-1909024

RESUMEN

This investigation assessed histologically the pulp tissue reaction to glutaraldehyde (GA) and to a commercial collagen preparation in pulpotomized primary teeth of baboons. One hundred and eighty-eight primary teeth were pulpotomized; in half of them inflammation was induced prior to the treatment. The teeth were divided into five groups: in three of them GA was used as a pulp dressing and applied for 1 min (group 1), 5 min (group 2), or mixed into the paste (group 3); collagen was used in group 4 and in group 5 (control) IRM was placed directly over the pulp stumps. Follow-up times were two, eight, and 24 weeks. Total necrosis was observed only in the collagen group. Partial necrosis and severe inflammation also were seen mainly in this group, and when the GA was incorporated into the paste. Slight to moderate inflammation was evident in all groups two and eight weeks postoperatively; however, 78% of the teeth of group 2 (GA 5 min) were inflammation-free after 24 weeks. Partial dentin bridges were seen in 92% of the teeth of the control group, in 82% of group 2, and 50% each of groups 1 and 3 eight weeks postoperatively. Dentin bridges were present in only 4% of the collagen group. After 24 weeks, all the teeth in group 2 and 83% of group 1 had dentin bridges. We conclude that Zyderm (Colagen Corp. Palo Alto, CA) led to unacceptable results, 5 min application of GA presented the best healing response, and GA 1 min and IRM also were satisfactory.


Asunto(s)
Colágeno/efectos adversos , Pulpa Dental/efectos de los fármacos , Glutaral/farmacología , Cicatrización de Heridas/efectos de los fármacos , Animales , Papio , Pulpotomía , Diente Primario/cirugía
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