RESUMEN
Peripheral blood lymphocytes from four patients with ataxia telangiectasia (AT), an inherited disorder showing, among other features, radiosensitivity and a high frequency of cancers, were shown to be cytogenetically more sensitive to bleomycin than were lymphocytes from both normal individuals and a single patient with xeroderma pigmentosum. With cell survival techniques, a biphasic dose-response curve was seen for both normal and AT fibroblasts, although the AT cells showed a much lower survival. The increased sensitivity to bleomycin in AT cells might be expected since it is a radiomimetic drug, but more importantly the known action of bleomycin in producing DNA strand scission suggests that AT cells might be defective in rejoining a proportion of DNA strand breaks.
Asunto(s)
Ataxia Telangiectasia/tratamiento farmacológico , Bleomicina/farmacología , Ataxia Telangiectasia/genética , Ataxia Telangiectasia/metabolismo , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Aberraciones Cromosómicas , Reparación del ADN/efectos de los fármacos , Fibroblastos/efectos de los fármacos , Humanos , Linfocitos/efectos de los fármacosRESUMEN
The abilities of the Eli Lilly compounds LY150310, LY189332, and LY135305 to inhibit spontaneous metastasis and to increase animal survival were evaluated. These compounds represent widely varied structures and were evaluated because they have been found to inhibit thromboxane synthetase, cyclooxygenase, and thrombin activation, respectively. These biochemical processes have been proposed in the literature as targets for antimetastatic drugs. The purpose of this investigation was twofold: (a) to compare the antimetastatic activities of the Eli Lilly compounds to those of the reference antimetastatic compounds nafazatrom and RA233, and (b) to examine the correlation between inhibition of spontaneous lung metastasis and survival. Spontaneous metastasis of the Lewis lung carcinoma was used to evaluate the antimetastatic activity of the compounds. In this model 5 x 10(5) tumor cells were implanted into the gastrocnemius muscle, the primary tumor was resected on Day 14, and metastatic lung lesions were counted on Day 25. Compounds were administered every 12 h on Days 5 through 19. Nafazatrom, LY150310, LY189332, and LY135305 were found to inhibit spontaneous lung metastasis in a dose-dependent manner. The ED50 values for the respective inhibitions with these compounds were 50, 0.5, 2, and 0.35 mg/kg/day; the respective therapeutic indexes (LD50/ED50) were 7, 180, 255, and 511. To evaluate the effect of nafazatrom, LY150310, LY189332, and LY135305 on animal survival, the compounds were given at maximally antimetastatic doses of 200, 60, 20, and 6 mg/kg/day, respectively. Two dosing schedules were used: (a) on Days 5 through 19 and (b) on Day 5 until death. Neither the median survival times nor the numbers of long-term survivors were significantly changed with any of the compounds at any dosing schedule. RA233, given to a maximally tolerated dose of 200 mg/kg/day on Day 5 until death, did not inhibit lung metastasis and did not increase median survival time. Postmortem examination of animals dosed with nafazatrom, LY150310, LY189332, and LY135305 showed complete inhibition in lung lesions and the appearance of lesions in the liver, kidney, spleen, and brain. The results of this investigation show that the effect a compound has on the number of metastatic lesions in a target organ may not be predictive of its effect on survival. To successfully translate laboratory data into the clinic, survival should be considered as a predictor of a compound's potential clinical utility.
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Compuestos de Anilina/farmacología , Carcinoma/prevención & control , Imidazoles/farmacología , Neoplasias Pulmonares/prevención & control , Naftalenos/farmacología , Metástasis de la Neoplasia/prevención & control , Propilaminas/farmacología , Pirazolonas , Tetrahidronaftalenos/farmacología , Animales , Antineoplásicos/farmacología , Carcinoma/mortalidad , Carcinoma/secundario , Fenómenos Químicos , Química , Relación Dosis-Respuesta a Droga , Evaluación Preclínica de Medicamentos , Femenino , Fibrinolíticos/farmacología , Neoplasias Pulmonares/mortalidad , Neoplasias Pulmonares/secundario , Ratones , Mopidamol/farmacología , Metástasis de la Neoplasia/mortalidad , Pirazoles/farmacología , Distribución AleatoriaRESUMEN
Cells from patients with ataxia telangiectasia (A-T) were shown to be more sensitive to streptonigrin than were cells from normal individuals. A linear dose-dependent cell survival was observed for both normal and A-T cells exposed to streptonigrin (up to 1.5 ng/ml) for 3-hr, with the A-T cells being about twice as sensitive as were the normal cells (Do approximately 0.25 ng compared with Do approximately 0.5 ng). The extreme toxicity of streptonigrin is also seen in the response of DNA synthesis which is inhibited sharply in both A-T and normal cells using doses of up to 125 ng/ml, although the effect was less pronounced in A-T cells. A greater amount of time was needed for recovery of DNA synthesis in normal cells compared with that of A-T cells. Finally, chromosomes from both A-T lymphocytes and fibroblasts show about a doubling of breakage rate following exposure to streptonigrin. The increased sensitivity of A-T cells to streptonigrin appears to be fairly comparable to the sensitivity to ionizing radiation, bleomycin, or neocarzinostatin and provides further evidence that perhaps A-T cells are deficient in some form of DNA strand repair.
Asunto(s)
Ataxia Telangiectasia/patología , ADN/metabolismo , Estreptonigrina/farmacología , Ataxia Telangiectasia/genética , Supervivencia Celular/efectos de los fármacos , Cromosomas Humanos/efectos de los fármacos , Replicación del ADN/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Fibroblastos/efectos de los fármacos , Humanos , Linfocitos/citología , Linfocitos/efectos de los fármacosRESUMEN
INTRODUCTION: Antenatal hydronephrosis (ANH) is frequently detected on screening obstetric ultrasonography. Common ANH grading systems include the anterior-posterior diameter (APD) and the Society for Fetal Urology (SFU) grading system. Recent developments in the management of ANH include the use of fetal magnetic resonance imaging (MRI), and a new grading system - Urinary Tract Dilation (UTD). This study reviewed patients who underwent fetal MRI and ultrasound, and compared the grading systems across these imaging modalities. MATERIALS AND METHODS: Patients who underwent paired fetal MRI and ultrasound studies between January 2012 and January 2014 were included. Two pediatric urologists and a pediatric radiologist reviewed the studies. Data collected included APD, SFU grade, and UTD grade. Fleiss' kappa statistic determined the inter-rater reliability (IRR) of the SFU and UTD grading within each imaging modality. Intra-class correlation assessed the consistency of the APD measurements. RESULTS: Forty-seven patients and 88 renal units were evaluated. Median gestational age was 22 weeks. Kappa values of the SFU grading system indicated fair IRR for ultrasound imaging and moderate IRR for MRI imaging, while the UTD grading system reached moderate IRR for both. The IRR of the SFU grading system was improved with the use of MRI, while the UTD grading system was no different. The APD intraclass correlation coefficient improved significantly when measured by MRI. As the ultrasound SFU grade increased, the odds of the MRI SFU grade being scored higher increased by a factor of 3.7. There was no difference between ultrasound and MRI when using the UTD grading system. DISCUSSION: This study was the first to assess the UTD system in a cohort of patients who underwent paired ultrasound and MRI studies. The results suggested that the UTD system might improve IRR, compared with the SFU system. The use of fetal MRI may improve the IRR of the SFU grading system. It also found that the proportion of SFU grades was affected by the imaging modality, raising the possibility that MRI 'overcalls' the SFU grade, compared with ultrasound. This difference was not observed using the UTD grading system. The most important limitation was the selection bias favoring complex pathology with severe ANH diagnosed at an early gestational age. CONCLUSIONS: In this unique cohort, the UTD system improved IRR when compared to the SFU grading system. Fetal MRI improved the IRR of the SFU grading system, and improved the APD intraclass correlation. The SFU grading was likely to be higher when assessed by MRI vs ultrasound, but the UTD grade was not affected by the imaging modality.
Asunto(s)
Feto/diagnóstico por imagen , Hidronefrosis/diagnóstico por imagen , Imagen por Resonancia Magnética/estadística & datos numéricos , Ultrasonografía Prenatal/estadística & datos numéricos , Técnicas de Diagnóstico Urológico , Femenino , Humanos , Variaciones Dependientes del Observador , Embarazo , Reproducibilidad de los Resultados , Estudios Retrospectivos , Índice de Severidad de la EnfermedadRESUMEN
PURPOSE: The most common measurements of hydronephrosis are the anterior-posterior (AP) diameter and the Society for Fetal Urology (SFU) grading systems. To date, the inter-rater reliability (IRR) of these measures has not been compared in the postnatal period. The objectives of this study were to compare the IRR of the AP diameter and the SFU grading system in infants and to determine whether ultrasound findings other than pelvicalyceal dilation are associated with higher SFU grades. METHODS: Initial postnatal ultrasounds of infants seen from February 1, 2011, to January 31, 2012, with a primary diagnosis of congenital hydronephrosis were included for review. Ultrasound images were de-identified and reviewed by four pediatric urologists. IRR was calculated using the intraclass correlation (ICC) measure. A paired t test was used to compare ICCs. Associations between SFU grade and other ultrasound findings were tested using Chi-square or Fisher's exact tests. RESULTS: A total of 112 kidneys in 56 patients were reviewed. IRR of the SFU grading system was high (right kidney ICC = 0.83, left kidney ICC = 0.85); however, IRR of AP diameter measurement was higher (right kidney ICC = 00.97, left kidney ICC = 0.98; p < 0.001). Renal asymmetry (p < 0.001), echogenicity (p < 0.001), and parenchymal thinning (p < 0.001) were significantly associated with SFU grade 4 hydronephrosis on bivariable and multivariable analysis. CONCLUSIONS: The SFU grading system is associated with excellent IRR, although the AP diameter appears to have higher IRR. Physicians may consider ultrasound findings that are not explicitly included in the SFU system when assigning hydronephrosis grade, which may lead to variability in use of this classification system.
Asunto(s)
Hidronefrosis/diagnóstico por imagen , Riñón/diagnóstico por imagen , Atención Posnatal/métodos , Femenino , Estudios de Seguimiento , Humanos , Hidronefrosis/clasificación , Hidronefrosis/congénito , Lactante , Recién Nacido , Masculino , Curva ROC , Reproducibilidad de los Resultados , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , UltrasonografíaRESUMEN
A total of 160 1-2 day old chickens were fed a 2% cholesterol diet for a period of 8 to 42 days and compared with an equal number of controls. Aortas were analyzed for various indexes of reactivity of connective tissue, cholesterol content and scanning electron microscopy (SEM) characteristics of the endothelial lining. Cholesterol feeding for a period up to 6 weeks resulted in doubling the level of serum cholesterol. It was, however, without effect on the activity of prolyl hydroxylase, lysyl oxidase, collagenase and collagen content in the aortic wall. As early as 3 weeks of feeding significant changes occurred in total and esterified cholesterol content. At the same time endothelial cells were characteristically contracted with several long cytoplasmic elongations and protrusions. A significant decrease of activity of the above enzymes was found in aortic tissue with increased age of the chicken. Collagen content in aortas increased with age of chickens. It is concluded that cholesterol as an atherogenic agent induces marked changes in endothelial cells and lipids of chicken aorta at earlier periods, prior to the activation of connective tissue.
Asunto(s)
Arterias/patología , Arteriosclerosis/patología , Colesterol en la Dieta , Modelos Animales de Enfermedad , Animales , Aorta/enzimología , Aorta Torácica/patología , Arterias/efectos de los fármacos , Arterias/ultraestructura , Arteriosclerosis/sangre , Pollos , Colesterol/sangre , Colesterol/farmacología , Masculino , Microscopía Electrónica de Rastreo , Procolágeno-Prolina Dioxigenasa/metabolismo , Proteína-Lisina 6-Oxidasa/metabolismoRESUMEN
A series of 1-substituted 4-amino-1H-pyrazolo[3,4-b]pyridine-5-carboxylic acid esters and amides were synthesized and screened for anxiolytic activity in the shock-induced suppression of drinking (SSD) test. The compounds were also tested for their ability to displace [3H]flunitrazepam (FLU) from brain benzodiazepine (BZ) binding sites. Many compounds were active in these screens and, additionally, demonstrated a selectivity for the type 1 BZ (BZ1) receptor over the type 2 BZ (BZ2) receptor as indicated by Hill coefficients significantly less than unity and by analysis of [3H]FLU binding results from different brain regions. Based on the results of structure-activity studies of these compounds, a hypothesis was proposed to explain the structural features necessary for optimal interaction with brain BZ receptors. A detailed pharmacological evaluation of one of the most potent behaviorally active compounds (27) demonstrated it to be BZ1 selective; also, in comparison to diazepam, 27 showed minimal sedative and alcohol interactive properties at therapeutically effective doses.
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Ansiolíticos/farmacología , Pirazoles/farmacología , Piridinas/farmacología , Amidas/síntesis química , Amidas/farmacología , Animales , Ansiolíticos/síntesis química , Corteza Cerebral/efectos de los fármacos , Corteza Cerebral/metabolismo , Fenómenos Químicos , Química , Ésteres/síntesis química , Ésteres/farmacología , Pirazoles/síntesis química , Piridinas/síntesis química , Ratas , Relación Estructura-ActividadRESUMEN
The four isomers of 4-aminopyrrolidine-2,4-dicarboxylate (APDC) were prepared and evaluated for their effects at glutamate receptors in vitro. (2R,4R)-APDC (2a), an aza analog of the nonselective mGluR agonist (1S,3R)-1-aminocyclopentane-1,3-dicarboxylate (1S,3R)-ACPD, 1), was found to possess relatively high affinity for metabotropic glutamate receptors (mGluRs) (ACPD-sensitive [3H]glutamate binding IC50 = 6.49 +/- 1.21 microM) with no effects on radioligand binding to NMDA, AMPA, or kainate receptors up to 100 microM. None of the other APDC isomers showed significant mGluR binding affinity, indicating that this interaction is highly stereospecific. Both 1 and 2a were effective in decreasing forskolin-stimulated cAMP formation in the adult rat cerebral cortex (EC50 = 8.17 +/- 2.21 microM for 1; EC50 = 14.51 +/- 5.54 microM for 2a); however, while 1 was also effective in stimulating basal tritiated inositol monophosphate production in the neonatal rat cerebral cortex (EC50 = 27.7 +/- 5.2 microM), 2a (up to 100 microM) was ineffective in stimulating phosphoinositide hydrolysis in this tissue preparation, further supporting our previous observations that 2a is a highly selective agonist for mGluRs negatively coupled to adenylate cyclase. Microelectrophoretic application of either 1 or 2a to intact rat spinal neurons produced an augmentation of AMPA-induced excitation (95 +/- 10% increase for 1, 52 +/- 6% increase for 2a). Intracerebral injection of 1 (400 nmol) produced characteristic limbic seizures in mice which are not mimicked by 2a (200-1600 nmol, ic). However, the limbic seizures induced by 1 were blocked by systemically administered 2a in a dose-dependent manner (EC50 = 271 mg/kg, ip). It is concluded that (2R,4R)-APDC (2a) is a highly selective, systemically-active agonist of mGluRs negatively coupled to adenylate cyclase and that selective activation of these receptors in vivo can result in anticonvulsant effects.
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Adenilil Ciclasas/metabolismo , Agonistas de Aminoácidos Excitadores/síntesis química , Prolina/análogos & derivados , Receptores de Glutamato Metabotrópico/metabolismo , Animales , Animales Recién Nacidos , Anticonvulsivantes , Corteza Cerebral/metabolismo , Colforsina/farmacología , AMP Cíclico/biosíntesis , Agonistas de Aminoácidos Excitadores/metabolismo , Agonistas de Aminoácidos Excitadores/farmacología , Ácido Glutámico/metabolismo , Humanos , Enlace de Hidrógeno , Sistema Límbico/efectos de los fármacos , Ratones , Modelos Moleculares , Estructura Molecular , Prolina/química , Prolina/metabolismo , Prolina/farmacología , Ratas , Convulsiones/inducido químicamente , Convulsiones/prevención & control , Médula Espinal/efectos de los fármacos , Médula Espinal/fisiología , EstereoisomerismoRESUMEN
A successful method for screening pupils for scoliosis in a metropolitan public school system is outlined. The incidence of scoliosis increased to greater than 3% in the seventh-grade population. Approximately 15% of the patients with established diagnoses required active management.
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Tamizaje Masivo , Instituciones Académicas , Escoliosis/epidemiología , Adolescente , Niño , Colorado , Femenino , Humanos , Masculino , Examen Físico/métodos , Radiografía , Escoliosis/diagnóstico por imagenRESUMEN
We have described adjuvant effects of orally administered Quillaja saponins on the immune responses of mice fed inactivated rabies antigen (AG). The in vivo lymphocyte proliferation in mice fed antigen + saponin (AG + SAP) was significantly greater than that in mice fed antigen (AG) alone. Further, the mitogen-induced cell proliferative responses in animals primed with AG + SAP was markedly increased compared with those in the AG group. These changes in clonal expansion were associated with an enhanced helper T cell (Th) and B cell co-operation. The in vivo cell proliferation and in vitro mitogen-induced responses of mice fed AG + SAP correlated with enhanced antibody synthesis. In mice fed saponin alone, there were significant increases in clonal expansion and lymphocyte function. Our present data indicate that the immunocompetence in animals fed AG + SAP was indeed evoked by saponins. Cytotoxic T lymphocyte activity in mice fed SAP or AG + SAP was detected 7 days after booster, in contrast to 21 days in mice fed AG alone. The natural killer cell activity in mice fed SAP alone was greatly enhanced and persisted for an extended period of time.
Asunto(s)
Inmunidad/efectos de los fármacos , Saponinas/farmacología , Adyuvantes Inmunológicos , Administración Oral , Animales , Formación de Anticuerpos/efectos de los fármacos , Femenino , Inmunidad Celular/efectos de los fármacos , Células Asesinas Naturales/efectos de los fármacos , Células Asesinas Naturales/inmunología , Activación de Linfocitos/efectos de los fármacos , Cooperación Linfocítica/efectos de los fármacos , Ratones , Ratones Endogámicos BALB C , Mitógenos/farmacología , Saponinas/administración & dosificación , Linfocitos T Citotóxicos/efectos de los fármacos , Linfocitos T Citotóxicos/inmunologíaRESUMEN
Neurotoxic sequelae of developmental lead exposure suggest that the hippocampus may be affected. Therefore, rats received low-level exposure via the milk of dams drinking 0.2% lead acetate beginning at parturition, and mid-dorsal sections of the hippocampus and dentate gyrus (DG) from 15-day-old pups were examined by light and electron microscopy. Lead exposure did not reduce body weight nor produce obviously abnormal vascularity or signs of cytotoxicity in the hippocampal formation, and total numbers per section of dentate granule cells or CA3 pyramidal cells were not reduced. On the other hand, lead exposure reduced neuropil development as evidenced both by reduced areas of the dentate hilus and dentate infrapyramidal stratum moleculare and by increased number of hilar CA3 pyramidal cells per unit area. Also, lead exposure reduced numbers of several types of synaptic profiles per unit area in the suprapyramidal mossy fiber zone. Complex invaginated (CI) profiles, assumed to be mature mossy fiber boutons, were characterized by multiple membrane densities and deep invaginations around dendritic spines of pyramidal cells. Complex noninvaginated (CN) boutons exhibited bag-like profiles with multiple membrane densities. Smaller, less numerous, simple (S) profiles contacted either dendritic trunks (ST) or spines (SS). Lead exposure reduced the numerical density of any of the profiles in the deep (close to stratum pyramidale) part of the proximal (close to DG) region of the suprapyramidal mossy fiber zone, but did not alter the numerical density of any of the profiles in the superficial (distal to stratum pyramidale) parts of either proximal or distal (close to CA1) regions. Average size of CN profiles in the distal region was increased by lead exposure. The pattern of effects suggests that low-level lead exposure during development preferentially affects later developing structures within the hippocampal formation, rather than affecting mature structures.
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Hipocampo/patología , Intoxicación por Plomo/patología , Animales , Peso Corporal , Hipocampo/ultraestructura , Intoxicación por Plomo/fisiopatología , Microscopía Electrónica , RatasRESUMEN
Our experience with the Bio-Rad "Quanta-Count" folate radioassay kit has revealed very good in-run precision and good day-to-day reproducibility in the assay of both serum and red-cell folate levels. Ascorbic acid is not required as folate preservative if blood samples are frozen within hours after collection. For the determination of red-cell folates, our data clearly show the need for maintenance of a certain level (6-8 gm%) of protein in the assay system. Protein (albumin or folate-free human serum) must be added to the red-cell lysate to compensate for the serum loss resulting from the high dilution factor necessary. In the absence of this added protein, red-cell values are markedly lower. A good correlation exists between red-cell folate values obtained from the assay of washed red cells and from the assay of whole blood with corrections for serum folate levels.
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Eritrocitos/análisis , Ácido Fólico/sangre , Ácido Ascórbico , Estabilidad de Medicamentos , Estudios de Evaluación como Asunto , Humanos , Métodos , Control de Calidad , Ensayo de Unión Radioligante , Análisis de RegresiónRESUMEN
Calcitic and aragonitic otoconia from the Japanese red-bellied newt, Cynops pyrrhogaster, were examined using an atomic force microscope. The surface structure of both otoconial polymorphs consisted of arrays of elements approximately 50 nm in diameter. Elements were generally round and were separated by shallow depressions of no more than 20 nm. The elements are suggested to be single crystals of calcium carbonate. The relationship of these observations to theories of otoconial genesis is discussed.
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Carbonato de Calcio/metabolismo , Membrana Otolítica/ultraestructura , Animales , Cristalización , Procesamiento de Imagen Asistido por Computador , Microscopía de Fuerza Atómica , Membrana Otolítica/metabolismo , Sáculo y Utrículo/metabolismo , SalamandridaeRESUMEN
A method is presented for encapsulating high molecular weight biological materials such as viral antigen, concanavalin A, and other proteins with cellulose acetate phthalate. The method is simple, inexpensive, and rapid; the process takes approximately 15 min. Capsules generated by this method are produced as microspheres 1-3 mm in diameter. They are stable for at least 6 h in simulated gastric conditions, but disintegrate rapidly under simulated intestinal conditions. Encapsulation had no effect on the activity of the biological materials. The method has potentially wide application for encapsulation of drugs and other substances.
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Microesferas , Antígenos Virales , Celulosa/análogos & derivados , Química Farmacéutica , Concanavalina A , Estabilidad de Medicamentos , Concentración de Iones de Hidrógeno , Radioisótopos de Yodo , Tamaño de la PartículaRESUMEN
Bovine herpesvirus-1 (BHV-1) was detected in Musca autumnalis De Geer after feeding on virus suspensions in bovine albumin or sucrose. Virus was detected for 48 h in flies fed an albumin suspension, with the highest titers recovered in crops (1.0 x 10(4) TCID50/ml) and whole-body (5 x 10(4) TCID50/ml/fly) specimens immediately after feeding; the level of virus declined rapidly thereafter. Virus titers in flies fed sucrose suspensions were 5 x 10(4) TCID50/ml in excised crops and 5 x 10(5) TCID50/ml in whole-body specimens; virus was not detected in flies 72 h after feeding. Four Hereford calves exposed for 4 h to BHV-1 fed flies did not develop any clinical symptoms related to BHV-1 transmission (i.e., elevated temperatures, ocular/nasal discharges, and labored breathing). Serum neutralization and plaque reduction tests did not show antibody production in calves exposed to BHV-1 infected flies. While we demonstrated that face flies retained BHV-1 for a short period of time, it does not appear that M. autumnalis is involved in either the mechanical or biological transmission of BHV-1.
Asunto(s)
Herpesvirus Bovino 1/crecimiento & desarrollo , Rinotraqueítis Infecciosa Bovina/transmisión , Mordeduras y Picaduras de Insectos/veterinaria , Insectos Vectores/microbiología , Muscidae/microbiología , Animales , Bovinos , Conducta Alimentaria , Mordeduras y Picaduras de Insectos/complicacionesRESUMEN
Groups of striped skunks (Mephitis mephitis) were inoculated intramuscularly with graded doses of street rabies virus. At various intervals after inoculation, saliva and sera were tested for rabies virus and neutralizing antibodies, respectively. Skunks that developed rabies were killed in terminal stages of the disease and the following examinations were made: titers of virus and antibody in submandibular salivary glands and brain, extent of immunofluorescence in submandibular salivary glands, and histologic examination of various tissues. Skunks that received inocula containing 4 x 10(4) to 4 x 10(5) mouse intracerebral lethal dose50 (MICLD50) had detectable serum neutralizing antibodies by 7-12 days postinoculation; however, most of the skunks that received lower doses (40 to 4 x 10(3) MICLD50) did not have detectable serum neutralizing antibodies until clinical signs began. In the salivary glands, slight and extensive immunofluorescence corresponded to high and low titers of tissue neutralizing antibody. Also low viral titers were associated with high tissue neutralizing antibody titers. There was a close correlation between viral titers in right and left submandibular salivary glands. The results suggest that the immune response can impede the process of infection of the salivary glands resulting in lack of antigen or low amounts of antigen in this tissue. This could occur through interference with centrifugal neural transport of virus and/or neutralization of virus during transfer from neural elements to epithelial cells. Lack of infectious virus or low viral titers in salivary glands containing antigen and high levels of tissue neutralizing antibodies can be caused partly by postmortem virus neutralization (during viral titration).
Asunto(s)
Carnívoros , Mephitidae , Rabia/inmunología , Saliva/microbiología , Animales , Anticuerpos Antivirales/análisis , Antígenos Virales/análisis , Encéfalo/microbiología , Pruebas de Neutralización , Rabia/microbiología , Virus de la Rabia/inmunología , Virus de la Rabia/aislamiento & purificación , Glándula Submandibular/microbiologíaRESUMEN
BACKGROUND: Noncardiac mortality in congestive heart failure (CHF) is substantial. OBJECTIVE: To define the specific causes of noncardiac mortality among hospitalized CHF patients. DESIGN: Retrospective medical record audit. SETTING: Three hospitals in British Columbia and Alberta, 1992-93. PATIENTS: A total of 2216 consecutive patients admitted with CHF. MAIN RESULTS: The overall mortality rate was 404 of 2216 (18%). Cause of death was cardiac in 290 of 404 (72%) patients, with an average age of 76 years. However, 114 of 404 (28%) deaths, in patients with an average age of 69 years, had noncardiac causes. Four causes accounted for almost 70%, of the noncardiac deaths: cancer (24%); pneumonia (16%); other pulmonary diseases, including embolism (15%); and cerebrovascular disease (11%). Renal disease (9%), gastrointestinal disorders (9%), non-pulmonic sepsis (7%), multiple system failure (5%) and trauma or surgical complications (4%) accounted for most of the remaining noncardiac deaths. CONCLUSIONS: Noncardiac causes produce a substantial proportion of deaths among elderly and sick CHF patients. As the survival of patients with CHF improves, the relative risk of noncardiac mortality in this population will likely increase. However, since hospitalized CHF patients so closely reflect their general population counterparts in terms of cause-specific mortality risk, the search for an ideal therapy might be viewed as a quixotic search for the cure of death.
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Causas de Muerte , Insuficiencia Cardíaca/mortalidad , Factores de Edad , Anciano , Canadá/epidemiología , Trastornos Cerebrovasculares/mortalidad , Femenino , Enfermedades Gastrointestinales/mortalidad , Humanos , Masculino , Persona de Mediana Edad , Insuficiencia Multiorgánica/mortalidad , Neoplasias/mortalidad , Estados Unidos/epidemiologíaRESUMEN
A new fluorinated analog of tilmicosin was synthesized by the reductive amination of desmycosin with 3,5-bis(trifluoromethyl)piperidine. Despite an apparently small change in structure, the fluorinated analog had much less in vitro antimicrobial activity than tilmicosin and it failed to protect 3-day old chicks against a Pasteurella multocida challenge at 64 mg/kg sc. In a preliminary in vivo fluorine NMR experiment in a female Sprague-Dawley rat, a 19F NMR signal was detected in the liver one hour after ip administration of the fluorinated compound. Therefore, although this fluorinated derivative had less antimicrobial activity than tilmicosin, it may nevertheless provide a suitable model of tilmicosin for pharmacokinetic studies using in vivo fluorine NMR.
Asunto(s)
Antibacterianos/síntesis química , Tilosina/análogos & derivados , Animales , Antibacterianos/farmacocinética , Antibacterianos/uso terapéutico , Pollos , Femenino , Hígado/efectos de los fármacos , Hígado/metabolismo , Espectroscopía de Resonancia Magnética , Pruebas de Sensibilidad Microbiana , Infecciones por Pasteurella/tratamiento farmacológico , Ratas , Ratas Sprague-Dawley , Relación Estructura-Actividad , Tilosina/síntesis química , Tilosina/farmacocinética , Tilosina/uso terapéuticoRESUMEN
Several insecticides were applied to cattle at various rates, mixtures, application methods and numbers of treatments and evaluated for control of cattle lice. The insecticides included permethrin at various rates as a pour-on with and without the synergist piperonyl butoxide (PBO), and also at various rates as a spray with and without PBO. Pirimiphos-methyl was evaluated as a pour-on at various rates and with one or two applications. Lambda cyhalothrin in microencapsulated formulation was compared to a non-microencapsulated formulation. Rabon(R) was applied as a pour-on at two rates and at one or two treatments for each rate. Dimilin(R) was applied as a pour-on at two rates and mixed with permethrin and applied at two rates. Five endectocides, Eprinex(R), Ivomec(R), Dectomax(R), Cydectin(R) and Phoenectin(R) were all applied at the same rate. The cattle utilized in this research were all infested with a mixture of lice species. The species included: Bovicola (Damalinia) bovis (L.), Haematopinus eurysternus (Nitzsch), Linognthus vituli (L.) and Solenoptes capillatus (Enderlein). Most of the cattle were infested with at least two species and some had three or all four species present. All of the treatments except permethrin 1.0%+5% PBO, at a rate of 3ml/45.4kgwt. provided acceptable lice control with one application. Data indicated that applying the insecticides in early January should provide enough control to render the need for a second treatment unnecessary.
Asunto(s)
Enfermedades de los Bovinos/tratamiento farmacológico , Insecticidas/uso terapéutico , Infestaciones por Piojos/veterinaria , Phthiraptera , Animales , Bovinos , Esquema de Medicación/veterinaria , Insecticidas/administración & dosificación , Infestaciones por Piojos/tratamiento farmacológico , Compuestos Organotiofosforados/administración & dosificación , Compuestos Organotiofosforados/uso terapéutico , Permetrina , Piretrinas/administración & dosificación , Piretrinas/uso terapéuticoRESUMEN
Examination of the records of 378 children with intussusception at our institution revealed that 29 cases were caused by an identifiable intestinal lesion. A Meckel's diverticulum was the causative agent in 21 children, all of whom were under 2 yr of age. A previously undiagnosed ileal lymphosarcoma produced the intussusception in six other children, all between 6 1/2 and 9 yr of age. Our experience indicates that any child over 6 yr of age with the clinical findings of colicky abdominal pain, bloody stools, and a palpable mass plus the radiographic evidence of intussusception must be considered to have ileal lymphosarcoma until proven otherwise. Hydrostatic reduction of the intussusception must be accompanied by extensive small bowel reflux of barium in order to effectively rule out a small intestinal lesion. If this is not accomplished, surgery should be planned with the suspicion that a malignancy may be present. If this suspicion is confirmed by frozen section, the operation procedure should include wide surgical excision of the lesion along with the regional lymph nodes.