RESUMEN
A Near Field/Far Field (NF/FF) model is a well-accepted tool for precautionary exposure assessment but its capability to estimate particulate matter (PM) concentrations is not well studied. The main concern is related to emission source characterization which is not as well defined for PM emitters compared to e.g. for solvents. One way to characterize PM emission source strength is by using the material dustiness index which is scaled to correspond to industrial use by using modifying factors, such as handling energy factors. In this study we investigate how well the NF/FF model predicts PM concentration levels in a paint factory. PM concentration levels were measured during big bag and small bag powder pouring. Rotating drum dustiness indices were determined for the specific powders used and applied in the NF/FF model to predict mass concentrations. Modeled process specific concentration levels were adjusted to be similar to the measured concentration levels by adjusting the handling energy factor. The handling energy factors were found to vary considerably depending on the material and process even-though they have the same values as modifying factors in the exposure models. This suggests that the PM source characteristics and process-specific handling energies should be studied in more detail to improve the model-based exposure assessment.
Asunto(s)
Contaminantes Atmosféricos/análisis , Contaminación del Aire/estadística & datos numéricos , Monitoreo del Ambiente , Residuos Industriales/análisis , Modelos Químicos , Material Particulado/análisis , PinturaRESUMEN
The objective of this study was to determine if distortion of the left subclavian artery course distinguishes double aortic arch with atretic left dorsal aorta from right aortic arch with mirror image branching. We performed a retrospective case series at a tertiary care center. Twenty-six patients undergoing magnetic resonance imaging for suspicion of a vascular ring were identified, 6 of whom had an atretic left dorsal aorta confirmed by surgical inspection. Six patients with the diagnosis of right aortic arch with mirror image branching were identified for comparison. The course of the left subclavian artery was assessed using surface-rendered magnetic resonance angiography (MRA) and axial fast spin echo images. All patients with double aortic arch had clinical symptoms suggestive of esophageal or tracheal compression. Six patients had double aortic arch, 3 of whom had an atretic left dorsal aorta. In these 3 patients, the branching patterns on MRA mimicked right aortic arch mirror image branching except for the distortion of the initial course of the left subclavian artery. Surgical observation confirmed the presence of an atretic left dorsal aorta that resulted in tension on the left subclavian artery pulling it posteriorly and inferiorly and completing the vascular ring. Patients with right aortic arch mirror image branching demonstrated no such subclavian artery distortion, and these patients did not have clinical symptoms suggestive of a vascular ring. Our results demonstrate that left subclavian artery distortion due to traction by an atretic left arch is an important diagnostic finding in the evaluation 6 patients with suspected vascular rings.
Asunto(s)
Aorta Torácica/anomalías , Anomalías Cardiovasculares/diagnóstico , Imagen por Resonancia Magnética , Arteria Subclavia/anomalías , Adolescente , Niño , Preescolar , Femenino , Humanos , Lactante , Angiografía por Resonancia Magnética , Masculino , Estudios RetrospectivosRESUMEN
BACKGROUND AND AIMS: A genetically impaired intestinal barrier function has long been suspected to be a predisposing factor for Crohn's disease (CD). Recently, mutations of the capsase recruitment domain family, member 15 (CARD15) gene have been identified and associated with CD. We hypothesise that a CARD15 mutation may be associated with an impaired intestinal barrier. METHODS: We studied 128 patients with quiescent CD, 129 first degree relatives (CD-R), 66 non-related household members (CD-NR), and 96 healthy controls. The three most common CARD15 polymorphisms (R702W, G908R, and 3020insC) were analysed and intestinal permeability was determined by the lactulose/mannitol ratio. RESULTS: Intestinal permeability was significantly increased in CD and CD-R groups compared with CD-NR and controls. Values above the normal range were seen in 44% of CD and 26% of CD-R but only in 6% of CD-NR, and in none of the controls. A household community with CD patients, representing a common environment, was not associated with increased intestinal permeability in family members. However, 40% of CD first degree relatives carrying a CARD15 3020insC mutation and 75% (3/4) of those CD-R with combined 3020insC and R702W mutations had increased intestinal permeability compared with only 15% of wild-types, indicating a genetic influence on barrier function. R702W and G908R mutations were not associated with high permeability. CONCLUSIONS: In healthy first degree relatives, high mucosal permeability is associated with the presence of a CARD15 3020insC mutation. This indicates that genetic factors may be involved in impairment of intestinal barrier function in families with IBD.
Asunto(s)
Enfermedad de Crohn/genética , Absorción Intestinal/genética , Péptidos y Proteínas de Señalización Intracelular/genética , Mutación , Adolescente , Adulto , Anciano , Enfermedad de Crohn/fisiopatología , Femenino , Predisposición Genética a la Enfermedad , Humanos , Péptidos y Proteínas de Señalización Intracelular/fisiología , Masculino , Persona de Mediana Edad , Proteína Adaptadora de Señalización NOD2 , Permeabilidad , Polimorfismo GenéticoRESUMEN
BACKGROUND: Mutations within the NOD2/CARD15 gene have recently been shown to be associated with Crohn's disease. AIMS: To investigate the clinical impact of the three common NOD2/CARD15 mutations in patients with Crohn's disease. METHODS: We investigated the prevalence of the three common NOD2/CARD15 mutations (Arg702Trp, Gly908Arg, 3020insC) in 180 patients with Crohn's disease, 70 patients with ulcerative colitis and 97 controls. In patients with Crohn's disease, prevalence of NOD2/CARD15 mutations were correlated to clinical and demographical parameters. RESULTS: In Crohn's disease patients, 35.6% carried at least one mutant allele of NOD2/CARD15 mutations compared with 14.3% of patients with ulcerative colitis (P = 0.006) and to 15.5% of controls (P = 0.0001). Genotype phenotype analyses revealed that NOD2/CARD15 mutations determined younger age at disease diagnosis (P = 0.03), ileal disease location (P = 0.01) and ileocecal resections (P = 0.0002). Interestingly, reoperation with resection of the anastomosis was significantly more frequent in patients with NOD2/CARD15 mutations (P = 0.01). CONCLUSIONS: Our investigations support the current hypothesis that NOD2/CARD15 mutations are associated with a phenotype of Crohn's disease with younger age at diagnosis, ileal involvement, ileocecal resections and a high risk of postoperative relapse and reoperation. NOD2/CARD15 mutations might therefore be used to identify high risk patients for relapse prevention strategies.
Asunto(s)
Proteínas Portadoras/genética , Enfermedad de Crohn/genética , Péptidos y Proteínas de Señalización Intracelular , Mutación/genética , Adolescente , Adulto , Femenino , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Proteína Adaptadora de Señalización NOD2 , Fenotipo , Reacción en Cadena de la Polimerasa/métodos , Polimorfismo de Nucleótido SimpleRESUMEN
Penetrating aortic ulceration is uncommon in the infrarenal aorta. We describe a patient with a penetrating infrarenal aortic ulcer manifesting as blue toe syndrome, and a second patient with a similar lesion identified as an incidental finding. These two patients were treated for penetrating infrarenal aortic ulceration within the past 9 months at two university-affiliated hospitals, a regional Veterans Administration Medical Center, and a County Medical Center. Both lesions demonstrated aneurysm changes with varying degrees of mural thrombus. The lesion filled with fresh thrombus proved labile, with embolization manifesting as blue toe syndrome. We support the aggressive treatment of aneurysmal penetrating aortic ulcer with aortic graft replacement to eliminate the potential for distal embolization and to obviate the risk of rupture and death.
Asunto(s)
Aneurisma Falso/diagnóstico por imagen , Aneurisma de la Aorta Abdominal/diagnóstico por imagen , Rotura de la Aorta/diagnóstico por imagen , Síndrome del Dedo Azul/diagnóstico por imagen , Embolia/diagnóstico por imagen , Úlcera/diagnóstico por imagen , Anciano , Aneurisma Falso/cirugía , Aneurisma de la Aorta Abdominal/cirugía , Rotura de la Aorta/cirugía , Aortografía , Implantación de Prótesis Vascular , Síndrome del Dedo Azul/cirugía , Diagnóstico Diferencial , Embolia/cirugía , Humanos , Masculino , Persona de Mediana Edad , Tomografía Computarizada por Rayos X , Úlcera/cirugíaRESUMEN
PURPOSE: Renal failure occurs in children with moderate frequency. Surgical aspects of establishing and maintaining dialysis access in small infants are exceptionally challenging. The purpose of this review is to evaluate the authors' experience with dialysis access for infants less than 10 kg, particularly with respect to the surgical care required. METHODS: A retrospective review was conducted between 1991 and 1999 of all pediatric dialysis patients weighing 10 kg or less (n = 29). Age at start of dialysis, duration of dialysis, modes of dialysis, and complications specific to peritoneal (PD) and hemodialysis (HD) were examined. RESULTS: The mean age at start of dialysis was 10.4 months and continued for an average duration of 16.3 months. Seventy-two percent of all patients required both modes of dialysis. HD and PD duration averaged 7.8 and 10.5 months, respectively. Catheter durability was 3.1 and 4.5 months per catheter for HD and PD, respectively. There was no significant difference in complications when comparing HD and PD. Patients who weighed 5 to 10 kg had significantly longer PD catheter durability than patients 0 to 5 kg (P = .001). Forty-one percent of patients terminated dialysis after transplantation, whereas 24% died awaiting transplantation. CONCLUSION: Despite a large number of operations required, infants less than 10 kg can be bridged successfully, by surgical intervention and subsequent dialysis, to transplantation.
Asunto(s)
Catéteres de Permanencia , Diálisis Peritoneal/métodos , Diálisis Renal/métodos , Insuficiencia Renal/terapia , Peso Corporal , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Diálisis Peritoneal/mortalidad , Probabilidad , Insuficiencia Renal/diagnóstico , Insuficiencia Renal/mortalidad , Insuficiencia Renal/cirugía , Estudios Retrospectivos , Medición de Riesgo , Sensibilidad y Especificidad , Procedimientos Quirúrgicos Operativos/métodos , Tasa de Supervivencia , Resultado del TratamientoRESUMEN
PURPOSE: After reconstruction of jejunal atresias at the ligament of Treitz, many patients do not respond to simple tapering and anastomosis requiring repetitive operations because of dysfunction of dilated proximal bowel. A new operative approach using lateral duodenectomy and duodenojejunostomy (LDAD) is reported. METHODS: Three infants with atresias within 10 cm of the ligament of Treitz were treated with LDAD, and their records are reviewed retrospectively. The entire duodenum is visualized after creating a malrotation; this is followed by opening the dilated duodenum and resecting dilated proximal jejunum. The resection is extended proximally, incorporating the lateral duodenal incision, excising the lateral duodenal wall, and preserving the ampulla. The residual duodenum is fashioned into a tube and anastomosed to the spatulated distal jejunum. RESULTS: Three infants underwent this procedure over a 4-year period. Two had undergone tapering enteroplasties previously but were unable to tolerate oral feedings; 1 infant had LDAD primarily. All were ultimately successfully managed by LDAD and were feeding within 14 days. Follow-up is from 14 to 49 months. CONCLUSION: Although experience is limited to 3 patients, the prompt return of intestinal function with LDAD may justify primary use of this more radical procedure in difficult-to-treat proximal atresias.
Asunto(s)
Duodenostomía , Duodeno/cirugía , Enfermedades del Prematuro/cirugía , Recien Nacido Prematuro , Atresia Intestinal/cirugía , Yeyunostomía , Humanos , Recién Nacido , Estudios RetrospectivosRESUMEN
BACKGROUND: Inhibition of apoptosis may allow cells with drug-induced damage to escape programmed cell death. The bcl-2 protein inhibits apoptosis and bcl-2 overexpression has been associated with drug resistance. It is our hypothesis that higher levels of bcl-2 expression will be seen in colon cancer cells resistant to PYY treatment. METHODS: Caco2 and HCT116 colon cancer cells were treated with 2 microM PYY for 24 hours. Protein was extracted from cells surviving PYY treatment; bcl-2 expression was measured by enzyme-linked immunosorbent assay (ELISA) and confirmed by Western blotting. RESULTS: Caco2 and HCT116 cells surviving PYY treatment demonstrated increased bcl-2 from 20.54+/-2.7 to 28.63+/-2.20 units/mL (P <0.05) and 21.98+/-1.28 to 29.32*+/-2.26 units/mL, respectively. CONCLUSIONS: Increased expression of bcl-2 is seen in a population of colon cancer cells resistant to PYY. Hence, bcl-2 may protect neoplastic cells from apoptosis; its levels may be useful in predicting chemotherapy response and in selecting appropriate drug regimens.
Asunto(s)
Apoptosis , Neoplasias del Colon/genética , Genes bcl-2/genética , Péptido YY/farmacología , Proteínas Proto-Oncogénicas c-bcl-2/biosíntesis , Western Blotting , Supervivencia Celular , Neoplasias del Colon/tratamiento farmacológico , Ensayo de Inmunoadsorción Enzimática , Humanos , Proteínas Proto-Oncogénicas c-bcl-2/genética , Células Tumorales CultivadasRESUMEN
Two analyses were conducted to examine gender differences in global self-esteem. In analysis I, a computerized literature search yielded 216 effect sizes, representing the testing of 97,121 respondents. The overall effect size was 0.21, a small difference favoring males. A significant quadratic effect of age indicated that the largest effect emerged in late adolescence (d = 0.33). In Analysis II, gender differences were examined using 3 large, nationally representative data sets from the National Center for Education Statistics (NCES). All of the NCES effect sizes, which collectively summarize the responses of approximately 48,000 young Americans, indicated higher male self-esteem (ds ranged from 0.04 to 0.24). Taken together, the 2 analyses provide evidence that males score higher on standard measures of global self-esteem than females, but the difference is small. Potential reasons for the small yet consistent effect size are discussed.
Asunto(s)
Autoimagen , Caracteres Sexuales , Adolescente , Adulto , Femenino , Identidad de Género , Humanos , Masculino , Desarrollo de la Personalidad , Pruebas de Personalidad/estadística & datos numéricos , PsicometríaRESUMEN
BACKGROUND: Nitric oxide (NO) and its role in surgical inflammation are well documented; demonstrating the role of NO in necrotizing enterocolitis (NEC) and ways in which it may be suppressed may provide avenues for immune modulation in the treatment of NEC. AIMS: We sought to demonstrate an increase in inducible nitric oxide synthase (iNOS) mRNA and nitric oxide in an experimental model of necrotizing enterocolitis. In addition, we hypothesized that interleukin-10 (IL-10) would attenuate this response. METHODS: Newborn rats were treated with 25 microliters intraperitoneal IL-10 or vehicle prior to laparotomy, 1 h superior mesenteric artery (SMA) occlusion, 50 micrograms/kg intraluminal platelet activating factor administration, and SMA reperfusion. iNOS mRNA and nitric oxide levels were measured in the liver, small bowel, and serum and compared using Student's t-test. RESULTS: Small bowel iNOS mRNA increased after NEC induction from 0.058 +/- 0.02 to 0.144 +/- 0.05 relative intensity units (RIU) at 2 h (p < 0.01) and from 0 to 0.09 +/- 0.02 RIU at 6 h (p < 0.03). Liver mRNA increased from 0.026 +/- 0.002 to 0.485 +/- 0.09 RIU (p < 0.002) and from 0 to 0.069 +/- 0.02 RIU (p < 0.0001) at 2 and 6 h, respectively. Serum nitric oxide increased in NEC induced animals at 2 h from 28.04 +/- 10.5 to 45.18 +/- 6.8 microM (p < 0.001). IL-10 suppressed iNOS mRNA and nitric oxide expression at 2 h in small bowel, liver, and serum by 60%, 89%, and 11%, respectively. CONCLUSIONS: IL-10 decreases iNOS mRNA response in experimental NEC. This down-regulation may be an avenue for anti-inflammatory intervention in NEC.
Asunto(s)
Enterocolitis Necrotizante/fisiopatología , Interleucina-10/farmacología , Óxido Nítrico Sintasa/metabolismo , Animales , Animales Recién Nacidos , Modelos Animales de Enfermedad , Enterocolitis Necrotizante/metabolismo , Intestino Delgado/metabolismo , Hígado/metabolismo , Óxido Nítrico/sangre , Óxido Nítrico Sintasa de Tipo II , RatasRESUMEN
Neoadjuvant chemotherapy (NC) has been shown to reduce primary breast tumor size in 80 to 90 per cent of patients. This study prospectively evaluated a series of women with locally advanced operable breast cancer treated with NC with the purpose of identifying eligibility for breast conservation surgery (BC) and clinical parameters predictive of chemotherapy response. Patients with stage IIB and III primary operable breast cancer were evaluated prospectively between 1/1/91 and 12/31/95. Thirty-two patients received NC consisting of three cycles of 5-fluorouracil, doxirubicin, and cyclophosphamide. Prechemotherapy tumor size was assessed by palpation and mammography. Patients were offered BC depending on clinical response. Initial tumor size averaged 7 cm (range, 4-15 cm). Reduction of > 50 per cent in tumor size occurred in 17 patients (53%). Twenty-one patients (66%) were potential candidates for BC based on a post-NC pathologic tumor size of less than 4 cm. Five patients (16%) had no residual breast tumor. Four patients underwent BC (13%). Partial response was not associated with patients age, menopausal status, tumor steroid receptor or Her-2/NEU positivity, or tumor size. Patients with a clinically negative axilla had a higher likelihood of partial or complete response. NC in patients with locally advanced breast disease has a high response rate (88%) and can significantly reduce tumor size to enable conservation of the breast.
Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Mastectomía Segmentaria , Factores de Edad , Antibióticos Antineoplásicos/administración & dosificación , Antimetabolitos Antineoplásicos/administración & dosificación , Antineoplásicos Alquilantes/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Axila , Neoplasias de la Mama/patología , Neoplasias de la Mama/cirugía , Quimioterapia Adyuvante , Ciclofosfamida/administración & dosificación , Doxorrubicina/administración & dosificación , Femenino , Fluorouracilo/administración & dosificación , Predicción , Humanos , Ganglios Linfáticos/patología , Metástasis Linfática , Mamografía , Menopausia , Persona de Mediana Edad , Estadificación de Neoplasias , Neoplasia Residual , Palpación , Estudios Prospectivos , Receptor ErbB-2/análisis , Receptores de Esteroides/análisis , Inducción de RemisiónRESUMEN
Two distinctive late-life challenges, community relocation and caring for an adult child with mental retardation, were studied to determine their influence on coping and well-being. These challenges differ in terms of their normativeness, duration, and whether they were expected. Data from 2 ongoing longitudinal studies (N = 449) were used to test the hypotheses that women experiencing residential relocation would report higher well-being and use problem-focused coping more frequently than women with long-term caregiving responsibilities. As predicted, more positive changes in well-being across time were reported by the relocation sample, which also showed more problem-focused coping. Women in the caregiving sample, however, showed stronger relationships between coping and well-being, underscoring possible gains in expertise that accompany challenges of lengthy duration.
Asunto(s)
Adaptación Psicológica , Envejecimiento/psicología , Cuidadores/psicología , Acontecimientos que Cambian la Vida , Anciano , Anciano de 80 o más Años , Femenino , Felicidad , Humanos , Discapacidad Intelectual , Estudios Longitudinales , Persona de Mediana Edad , Estrés PsicológicoRESUMEN
The purpose of this study was to evaluate the utility of ductography, or galactography, in identifying ductal abnormalities in patients presenting with abnormal nipple discharge and to correlate these findings with pathologic results. Abnormal nipple discharge was defined as either bloody or testing positive for occult blood. Milky discharge (galactorrhea) was not evaluated. From July 1992 to June 1994, a total of 43 women presented to the UCLA Breast Center with complaints of abnormal nipple discharge. Mean age of the patients was 54.9 years. All patients underwent technically adequate ductography. A total of 25 patients then underwent 26 excisional biopsies for abnormal ductographic findings. Surgery was usually simplified by the appropriate ductal injection of methylene blue immediately preoperatively. No complications from the procedure were identified. Pathologic entities were correlated with ductographic findings. Ductography identified ductal abnormalities in 33/45 (73%) of ductograms. Filling defects were noted in 19/45 (42%) of ductograms, ductal dilatation in 3/45 (7%), both filling defects and dilatation were noted in 11/45 (24%) of ductograms, and 12/45 (27%) were normal ductograms. Pathologically, ductographic anomalies correlated well with histologic findings. We conclude that ductography is an effective and safe means of identifying ductal abnormalities in patients with abnormal breast discharge. A high incidence of benign intraductal papilloma and a moderate risk of cancer and precancerous lesions were identified. We believe that patients with abnormal nipple discharge should undergo routine ductography and dye localization before surgery.
Asunto(s)
Pezones/diagnóstico por imagen , Enfermedades de la Mama/diagnóstico por imagen , Neoplasias de la Mama/diagnóstico por imagen , Dilatación Patológica , Estudios de Evaluación como Asunto , Femenino , Humanos , Persona de Mediana Edad , Papiloma Intraductal/diagnóstico por imagen , RadiografíaRESUMEN
Full thickness rectal prolapse is a distressing and debilitating condition that often affects elderly patients. Fecal incontinence is usually present. Frequently, comorbid conditions or previous pelvic procedures complicate surgical care. A perineal approach may be used in these patients to avoid the complications of pelvic surgery and general anesthesia. The Delorme operation involves mucosal stripping and muscle plication of the rectal prolapse and is performed externally under regional or general anesthesia. We report our experience with this procedure in six elderly candidates who have undergone the Delorme procedure at the UCLA Center for Health Sciences in the past year. Two men and four women with a mean age of 78 +/- 12 years were followed over a mean of 11 +/- 4 months. Complicating factors included a mean of 1.7 failed prolapse operations per patient (0-6), pelvic radiation in two patients, and severe cardiac and pulmonary disease in two patients. Outpatient bowel preparations and same day admissions were used. Operative time averaged 80 minutes. No blood transfusions were required and postoperative stay averaged 2.7 days. A total of 67 per cent report improvement in continence. There was no major morbidity or mortality and only one recurrence. We conclude that the Delorme procedure is a safe and useful procedure for the treatment of complete rectal prolapse. Elderly patients, patients with failed prolapse operations, and those with prior pelvic surgery or radiation should be considered for this procedure.
Asunto(s)
Prolapso Rectal/cirugía , Anciano , Anciano de 80 o más Años , Incontinencia Fecal/etiología , Incontinencia Fecal/cirugía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Prolapso Rectal/complicaciones , Procedimientos Quirúrgicos Operativos/métodos , Resultado del TratamientoRESUMEN
Perfluorooctanoic acid (PFOA) and perfluorodecanoic acid (PFDA) are peroxisome proliferators that cause hepatotoxicity in rodents. This study shows that PFDA activates liver phospholipase C (PLC) and inhibits CTP:phosphocholine cytidylyltransferase (CT). PLC cytosolic and microsomal activities were increased 1.4- and 1.7-fold, respectively. CT activates were decreased to 58% (cytosol) and 36% (microsome) of control values. PFDA also caused a threefold increase in liver diacylglycerol (DAG) concentration. PFOA had no effect on the enzyme activities or DAG concentration. Together with previous results, these data suggest that PFDA activates a phosphatidylcholine-specific PLC causing an increase in liver phosphocholine and DAG. These effects are discussed in relation to cellular signalling processes that may provide a mechanism for PFDA-induced hepatotoxicity.
Asunto(s)
Ácidos Decanoicos/toxicidad , Diglicéridos/metabolismo , Fluorocarburos/toxicidad , Hígado/efectos de los fármacos , Nucleotidiltransferasas/antagonistas & inhibidores , Fosfatidilcolinas/metabolismo , Fosfolipasas de Tipo C/efectos de los fármacos , Análisis de Varianza , Animales , Citosol/efectos de los fármacos , Ingestión de Alimentos/efectos de los fármacos , Hígado/química , Hígado/enzimología , Hígado/metabolismo , Masculino , Microcuerpos/efectos de los fármacos , Microsomas/efectos de los fármacos , Nucleotidiltransferasas/efectos de los fármacos , Ratas , Ratas Endogámicas F344 , Fosfolipasas de Tipo C/metabolismoRESUMEN
In compartmentalized self-organization, positive and negative self-beliefs are separated into distinct categories (i.e., self-aspects), so that each self-aspect contains primarily positive or primarily negative beliefs. In evaluatively integrative organization, self-aspect categories contain a mixture of positive and negative beliefs. Positive-compartmentalized individuals recovered easily from a sad mood when they could reflect on personally important, pure positive self-aspects. When situational factors maintained the activation of pure negative self-aspects, compartmentalization seemed to perpetuate the negative mood. These studies suggest that people with a positive-compartmentalized self (who usually report high self-esteem and positive mood) have a hidden vulnerability to intense negative states. The advantages of an evaluatively integrated self may require having the opportunity to reflect on (and integrate) positive and negative beliefs about the self.
Asunto(s)
Adaptación Psicológica , Depresión/psicología , Desarrollo de la Personalidad , Autoimagen , Adulto , Femenino , Humanos , Individualidad , Control Interno-Externo , Inventario de PersonalidadRESUMEN
We investigated the restoration in peripheral nerve function and simple neurobehavioral reflexes in the freeze-tolerant wood frog (Rana sylvatica). Thirty-two specimens, allowed to freeze for 39 h and ultimately cooled to -2.2 degrees C, were sampled at various time intervals up to 60 h after thawing at 5 degrees C was initiated. The sciatic nerves of treated frogs were initially unresponsive to stimulation, but usually regained excitability within 5 h. Except for a slight reduction in nerve excitability, characteristics of the compound action potentials of treated frogs were indistinguishable from those of control frogs. Recovery times for the hindlimb retraction and righting reflexes were 8 h and 14 h, respectively. Concentrations of the cryoprotectant glucose increased 8.2-fold in the sciatic nerve and 10.5-fold in the underlying semimembranosis muscle of treated frogs, and remained elevated for at least 60 h after thawing was initiated. These organs lost 47.2% and 15.9%, respectively, of their water during freezing, but were rehydrated within 2 h of the onset of thawing. The accumulation of glucose and the withdrawal of tissue water apparently are cryoprotective responses which enable this species to survive freezing.
Asunto(s)
Congelación , Ranidae/fisiología , Nervio Ciático/fisiología , Potenciales de Acción , Animales , Agua Corporal , Crioprotectores , Glucosa/análisis , Masculino , Músculos/química , Nervio Ciático/química , Factores de TiempoRESUMEN
The in vitro interaction of modulators of topoisomerase I and II with cisplatin in human ovarian carcinoma cells might be synergistic. The interactions were evaluated by median effect analysis of survival data derived from continuous exposure to drug combinations for 10 days in colony-forming assays. The interaction between cisplatin and the topoisomerase I inhibitor camptothecin and the topoisomerase I activator beta-lapachone was additive, as was that between cisplatin and the topoisomerase II inhibitor novobiocin. Despite the clinical efficacy of the combination of etoposide (a topoisomerase II inhibitor) and cisplatin, the combination index at 50% cell kill indicated antagonism between these two drugs. Thus, biochemical synergism at the cellular level is not a prerequisite of improved therapeutic efficacy.
Asunto(s)
Cisplatino/uso terapéutico , ADN-Topoisomerasas de Tipo I/efectos de los fármacos , Etopósido/farmacología , Neoplasias Ováricas/tratamiento farmacológico , Inhibidores de Topoisomerasa II , Antibióticos Antineoplásicos/farmacología , Camptotecina/farmacología , Línea Celular , Interacciones Farmacológicas , Femenino , Humanos , Naftoquinonas/farmacología , Novobiocina/farmacología , Neoplasias Ováricas/enzimología , Inhibidores de Topoisomerasa I , Células Tumorales Cultivadas/efectos de los fármacos , Células Tumorales Cultivadas/enzimologíaRESUMEN
The possibility of content bias in the MacAndrew's Alcoholism Scale (MAC) from the MMPI was examined in groups of seizure disorder (n = 35), general medical (n = 25), and psychiatric patients (n = 20). Scores above criteria on the MAC were associated with reported alcohol problems only for the psychiatric patients. Almost 50% of the seizure patients with no such history had scores above criteria on the MAC. This classification inaccuracy is even greater than that reported recently in contemporary normal samples. The results suggest that caution should be used when one is administering the MAC to seizure disorder patients and that further investigation of possible content bias in other MMPI scales or subscales should be pursued.