RESUMEN
Human thought is prone to biases. Some biases serve as beneficial heuristics to free up limited cognitive resources or improve well-being, but their neurocognitive basis is unclear. One such bias is a tendency to construe events in the distant future in abstract, general terms and events in the near future in concrete, detailed terms. Temporal construal may rely on our capacity to orient toward and/or imagine context-rich future events. We tested 21 individuals with impaired episodic future thinking resulting from lesions to the hippocampus or ventromedial prefrontal cortex (vmPFC) and 57 control participants (aged 45-76 years) from Canada and Italy on measures sensitive to temporal construal. We found that temporal construal persisted in most patients, even those with impaired episodic future thinking, but was abolished in some vmPFC cases, possibly in relation to difficulties forming and maintaining future intentions. The results confirm the fractionation of future thinking and that parts of vmPFC might critically support our ability to flexibly conceive and orient ourselves toward future events.
Asunto(s)
Memoria Episódica , Pensamiento , Humanos , Imaginación , Hipocampo , Corteza Prefrontal/diagnóstico por imagen , PredicciónRESUMEN
BACKGROUND: Infancy is a developmental stage with heightened susceptibility to environmental influences on the risk of chronic childhood disease. Few birth cohort studies have detailed measures of fungal diversity data in infants' bedrooms, limiting the potential to measure long-term associations of these complex exposures with development of asthma or allergy. OBJECTIVE: We evaluated the relation of home fungal levels in infancy to repeated measures of wheeze and development of asthma and rhinitis by age 13, and sensitization by age 12 years. METHODS: In the Epidemiology of Home Allergens and Asthma prospective birth cohort study, we recruited 408 children with family history of allergic disease or asthma. When children were aged 2-3 months, we measured culturable fungi in bedroom air and dust, and in outdoor air. Main outcomes included ascertainment of symptoms/disease onset by questionnaire from birth through age 13. We estimated hazard ratios and, for wheeze and sensitization, odds ratios for an interquartile increase in log-transformed fungal concentrations, adjusting for other outcome predictors and potential confounders. RESULTS: Elevated levels of yeasts in bedroom floor dust were associated with reduced: i) wheeze at any age; ii) fungal sensitization; and iii) asthma development by age 13 (hazard ratio (HR) = 0.86; 95% confidence interval (CI), [0.75 to 0.98]). Outdoor airborne Cladosporium and dustborne Aspergillus predicted increased rhinitis. Risk of fungal sensitization by age 12, in response to environmental Alternaria and Aspergillus, was elevated in children with a maternal history of fungal sensitization. CONCLUSIONS AND CLINICAL RELEVANCE: Despite the irritant and allergenic properties of fungi, early-life elevated dust yeast exposures or their components may be protective against allergy and asthma in children at risk for these outcomes. Ascertainment of fungal components associated with immunoprotective effects may have therapeutic relevance for asthma.
Asunto(s)
Contaminación del Aire Interior , Asma , Hongos , Asma/epidemiología , Asma/etiología , Niño , Preescolar , Femenino , Estudios de Seguimiento , Humanos , Lactante , Recién Nacido , Masculino , Estudios RetrospectivosRESUMEN
OBJECTIVE: Complications after cranioplasty after decompressive craniectomy (DC) have been reported to be as high as 40%. The superficial temporal artery (STA) is at substantial risk for injury in standard reverse question-mark incisions that are typically used for unilateral DC. The authors hypothesize that STA injury during craniectomy predisposes patients to post-cranioplasty surgical site infection (SSI) and/or wound complication. METHODS: A retrospective study of all patients at a single institution who underwent cranioplasty after decompressive craniectomy and who underwent imaging of the head (computed tomography angiogram, magnetic resonance imaging with intravenous contrast, or diagnostic cerebral angiography) for any indication between the two procedures was undertaken. The degree of STA injury was classified and univariate statistics were used to compare groups. RESULTS: Fifty-four patients met inclusion criteria. Thirty-three patients (61%) had evidence of complete or partial STA injury on pre-cranioplasty imaging. Nine patients (16.7%) developed either an SSI or wound complication after cranioplasty and, among these, four (7.4%) experienced delayed (>2 weeks from cranioplasty) complications. Seven of 9 patients required surgical debridement and cranioplasty explant. There was a stepwise but non-significant increase in post-cranioplasty SSI (STA present: 10%, STA partial injury: 17%, STA complete injury: 24%, P=0.53) and delayed post-cranioplasty SSI (STA present: 0%, STA partial injury: 8%, STA complete injury: 14%, P=0.26). CONCLUSIONS: There is a notable but statistically non-significant trend toward increased rates of SSI in patients with complete or partial STA injury during craniectomy.
Asunto(s)
Craniectomía Descompresiva , Arterias Temporales , Humanos , Estudios Retrospectivos , Arterias Temporales/cirugía , Craniectomía Descompresiva/métodos , Infección de la Herida Quirúrgica/diagnóstico , Infección de la Herida Quirúrgica/etiología , Infección de la Herida Quirúrgica/cirugía , Cráneo/cirugía , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/cirugíaRESUMEN
At room temperature, a 10 µm cut-off wavelength coincides with an infrared spectral window and the peak emission of blackbody objects. We report a 10 µm cut-off wavelength InAs/GaSb T2SL p-i-n diode on a GaAs substrate with an intentional interfacial misfit (IMF) array between the GaSb buffer layer and GaAs substrate. Transmission electron microscopy and energy-dispersive X-ray spectroscopy revealed that the heterostructure on GaSb-on-GaAs is epitaxial, single-crystalline but with a reduced material homogeneity, extended lattice defects and atomic segregation/intermixing in comparison to that on the GaSb substrate. Strain-induced degradation of the material quality is observed by temperature-dependent current-voltage measurements. The T2SL with the IMF array appears as a potentially effective route to mitigate the impact of the lattice mismatch once its fabrication is fully optimized for these systems, but additional strain compensating measures can enable a low cost, scalable manufacturing of focal plane arrays (FPA) for thermal imaging cameras for spectroscopy, dynamic scene projection, thermometry, and remote gas sensing.
RESUMEN
A current debate in the literature is whether all declarative memories and associated memory processes rely on the same neural substrate. Here, we show that H.C., a developmental amnesic person with selective bilateral hippocampal volume loss, has a mild deficit in personal episodic memory, and a more pronounced deficit in public event memory; semantic memory for personal and general knowledge was unimpaired. This was accompanied by a subtle difference in impairment between recollection and familiarity on lab-based tests of recognition memory. Strikingly, H.C.'s recognition did not benefit from a levels-of-processing manipulation. Thus, not all types of declarative memory and related processes can exist independently of the hippocampus even if it is damaged early in life.
Asunto(s)
Amnesia/fisiopatología , Memoria/fisiología , Recuerdo Mental/fisiología , Femenino , Humanos , Pruebas Neuropsicológicas , Curva ROC , Adulto JovenRESUMEN
Does advantageous decision-making require one to explicitly remember the outcome of a series of past decisions or to imagine future personal consequences of one's choices? Findings that amnesic people with hippocampal damage cannot form a clear preference for advantageous decks over many learning trials on the Iowa Gambling Task (IGT) have been taken to suggest that complex decision-making on the IGT depends on declarative (episodic) memory and hippocampal integrity. Alternatively, impaired IGT performance in amnesic individuals could be secondary to risk-taking and/or impulsive behaviour resulting from impaired episodic future thinking (i.e. prospection) known to accompany amnesia. We tested this possibility in the amnesic individual K.C. using the IGT and the Toronto Gambling Task (TGT), a novel task that dissociates impulsivity from risk-taking without placing demands on declarative memory. K.C. did not develop a preference for advantageous over disadvantageous decks on the IGT and, instead, showed a slight preference for short-term gains and an inability to acquire a more adaptive appreciation of longer-term losses. He also did not display impulsive or risk-taking behaviour on the TGT, despite a profound inability to imagine personal future experiences. These findings suggest that impaired decision-making on the IGT in amnesia is unlikely to reflect a predilection to act in the moment or failure to take future consequences into account. Instead, some forms of future-regarding decision-making may be dissociable, with performance on tasks relying on declarative learning or on episodic-constructive processes more likely to be impaired.
Asunto(s)
Amnesia/fisiopatología , Amnesia/psicología , Toma de Decisiones/fisiología , Conducta Impulsiva/fisiología , Asunción de Riesgos , Análisis de Varianza , Juegos Experimentales , Humanos , Masculino , Memoria Episódica , Persona de Mediana EdadRESUMEN
Suspensions of human lymphocytes and monocytes separated by the Ficoll-hypaque method from the peripheral blood show a Coulter volume distribution, measured with a multiparameter cell sorter, characterized by a minor peak at 500 mu3, containing 5-15% of the cells, and a major peak at 200 mu3. Using fluorescent latex particles we have found that the monocytes, the cells that ingest the latex particles, all lie in the 500 mu3 peak; conversely, all of the cells in the 500 mu3 peak are monocytes. When the cell suspensions are incubated, the monocytes increase both the average volume and in absolute numbers. The number of monocytes approximately doubles during 3 days of incubation, when it reaches its maximum value. At that time we have found that all of the monocytes lack receptors for sheep red blood cells and all possess receptors for human gamma-globulin. The increase in monocyte number appears, therefore, to arise from the enlargement of "monocyte presursors" that resemble lymphocytes in volume and resemble both the monocytes and the B lyphocytes with respect to surface sheep red blood cell and human gamma-globulin receptors.
Asunto(s)
Linfocitos/citología , Monocitos/citología , Animales , Autoanálisis , ADN/análisis , Eritrocitos/inmunología , Pruebas de Hemaglutinación , Látex , Linfocitos/inmunología , Microscopía/métodos , Microesferas , Monocitos/inmunología , Ovinos/inmunología , Coloración y EtiquetadoRESUMEN
The RBE for 125I relative to 30 keV X-rays, 4 MeV X-rays and 137Cs gamma rays was determined using the induction of micronuclei in human lymphocytes as the biological test system. The 125I photons were as effective as the 30 keV X-rays. If a micronuclei count of 50 per 1500 cells is used as the endpoint, the RBE for 125I was found to be about 1.8 and 1.6 when 4 MeV X-rays and 137Cs gamma rays were used as the reference radiation, respectively.
Asunto(s)
Radioisótopos de Yodo , Linfocitos/efectos de la radiación , Braquiterapia , Núcleo Celular/efectos de la radiación , Supervivencia Celular , Aberraciones Cromosómicas , Relación Dosis-Respuesta en la Radiación , Humanos , Técnicas In Vitro , Linfocitos/ultraestructura , Efectividad Biológica RelativaRESUMEN
The oral anticoagulant warfarin is clinically administered as a racemic mixture of two enantiomers, (R) and (S). Many relevant drug interactions with warfarin have been attributed to the specific metabolic inhibition of the elimination of the more pharmacologically active (S)-enantiomer. To investigate reports that acetaminophen can potentiate the anticoagulant effect of warfarin, 20 healthy male volunteers were each given single oral 20 mg doses of racemic warfarin on three separate occasions: (1) alone, (2) after 1 day of acetaminophen (4 g/d), and (3) after 2 weeks of acetaminophen (4 g/d). The urinary excretion pattern of acetaminophen and its metabolites was not significantly altered over its course of administration. The (R)- and (S)-enantiomers of warfarin exhibited significantly different pharmacokinetic properties. However, acetaminophen did not alter the disposition of either (R)- or (S)-warfarin. All subjects exhibited a pharmacodynamic response to racemic warfarin. The response was not significantly altered in the presence of acute or chronic acetaminophen dosing, as assessed by prothrombin time and factor VII concentrations.
Asunto(s)
Acetaminofén/farmacología , Analgésicos no Narcóticos/farmacología , Anticoagulantes/farmacocinética , Warfarina/farmacocinética , Acetaminofén/metabolismo , Acetaminofén/orina , Administración Oral , Adolescente , Alanina Transaminasa/efectos de los fármacos , Alanina Transaminasa/metabolismo , Análisis de Varianza , Aspartato Aminotransferasas/efectos de los fármacos , Aspartato Aminotransferasas/metabolismo , Estudios Cruzados , Relación Dosis-Respuesta a Droga , Interacciones Farmacológicas , Factor VII/efectos de los fármacos , Factor VII/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Tiempo de Protrombina , Estereoisomerismo , Factores de Tiempo , Warfarina/sangre , Warfarina/químicaRESUMEN
Ninety-one patients who underwent radical nephrectomy for renal cell carcinoma (RCC) were reviewed to determine the prognostic value of serum alkaline phosphatase (SAP) levels and radionuclide bone scan. A preoperative SAP greater than 127 IU/L was a strong indicator of eventual disease progression or death, and an elevated SAP was a better predictor of eventual outcome than bone scan.
Asunto(s)
Fosfatasa Alcalina/sangre , Neoplasias Óseas/secundario , Huesos/diagnóstico por imagen , Carcinoma de Células Renales/mortalidad , Neoplasias Renales/mortalidad , Neoplasias Óseas/diagnóstico por imagen , Neoplasias Óseas/mortalidad , Carcinoma de Células Renales/diagnóstico por imagen , Carcinoma de Células Renales/secundario , Femenino , Humanos , Masculino , Persona de Mediana Edad , Nefrectomía , Valor Predictivo de las Pruebas , Pronóstico , CintigrafíaRESUMEN
As the number of HIV-1 infected individuals and AIDS patients continues to increase, more cases involving the genitourinary tract will be encountered. Often, genitourinary manifestations will be the initial presentation of AIDS. Proper diagnosis will require awareness and a high index of suspicion. In addition to routine cultures, opportunistic infections with unusual organisms will require staining for fungi and acid-fast bacilli. Repeat cultures of blood, urine, seminal fluid, and abscess cavities may be required to establish a diagnosis. Prolonged courses of antibiotic treatment for prophylaxis and for relapses are usually required. Clinical understaging and rapid progression of tumors distinguish HIV-1-associated malignancies involving the genitourinary tract. Treatment for these malignancies will depend on the stage of HIV-1 infection. Any concomitant drug therapy and evidence of malnutrition will be important factors in selecting the proper timing and mode of therapeutic intervention. Although AIDS predominantly affects individuals between 30 and 50 years of age, an increasing percentage of patients over 50 years of age are being diagnosed. Common risk factors for acquisition of HIV include homosexuality or bisexuality and transfusion of blood or blood products. For the urologist, it is important to recognize that older patients more frequently present with AIDS at the time of diagnosis of HIV infection. A more rapid course of deterioration and high mortality is noted in this population. Clearly, protocols including surveillance, dosing regimens, and surgical intervention will need to be established and clarified to treat an anticipated increasing number of affected patients. In addition, it appears that adequate adherence to universal precautions is far from being achieved. Close monitoring and active surveillance of infection control may be needed to improve compliance.
Asunto(s)
Síndrome de Inmunodeficiencia Adquirida/complicaciones , Enfermedades Urogenitales Femeninas/etiología , Enfermedades Urogenitales Masculinas , Síndrome de Inmunodeficiencia Adquirida/diagnóstico , Síndrome de Inmunodeficiencia Adquirida/transmisión , Femenino , Humanos , Transmisión de Enfermedad Infecciosa de Paciente a Profesional/prevención & control , Masculino , UrologíaRESUMEN
A patient with von Recklinghausen's disease manifested by dermal neurofibromatosis and cafe-au-lait spots presented with complaints of malaise, weight loss, lower extremity weakness, and a palpable left lower abdominal quadrant mass. Evaluation revealed a lumbar neurofibroma, a localized primary carcinoid tumor of the mesentery, and a left renal angiomyolipoma. Although an association between neurofibromatosis and carcinoid has been previously reported, we believe this is the first report documenting the association of all three entities.
Asunto(s)
Tumor Carcinoide , Hemangioma , Neoplasias Renales , Lipoma , Mesenterio , Neoplasias Primarias Múltiples , Neurofibroma , Neurofibromatosis 1 , Neoplasias Peritoneales , Neoplasias de la Médula Espinal , Tumor Carcinoide/diagnóstico , Femenino , Hemangioma/diagnóstico , Humanos , Neoplasias Renales/diagnóstico , Lipoma/diagnóstico , Persona de Mediana Edad , Neoplasias Primarias Múltiples/diagnóstico , Neurofibroma/diagnóstico , Neurofibromatosis 1/diagnóstico , Neoplasias Peritoneales/diagnóstico , Neoplasias de la Médula Espinal/diagnósticoRESUMEN
Approximately 30 years ago, the finding that prostate acid phosphatase (PAP) was antigenically distinct from other acid phosphatases opened an era in the measurement of prostate cancer. Many immunoassays have been developed but their clinical significance has been limited. Studies comparing one or more assays in the same population of men with prostate cancer population have concluded that no differences were found in the sensitivities of the assays when the upper limits of normal were selected to provide equal specificities.
Asunto(s)
Fosfatasa Ácida/sangre , Biomarcadores de Tumor/sangre , Neoplasias de la Próstata/diagnóstico , Humanos , Isoenzimas/sangre , Masculino , MétodosRESUMEN
AIDS is clearly the most lethal of all the STDs. The universal adherence to "safe" sexual practices is required in order to try to limit this epidemic. Unfortunately, the other forms of transmission of HIV, intravenous injection and via the fetal-placental circulation, have ensured that simply altering the sexual practices of society would not be sufficient to end this epidemic quickly.
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Síndrome de Inmunodeficiencia Adquirida/transmisión , VIH-1 , Síndrome de Inmunodeficiencia Adquirida/complicaciones , Síndrome de Inmunodeficiencia Adquirida/epidemiología , Femenino , Humanos , Masculino , Infecciones Oportunistas/complicaciones , Factores de Riesgo , Conducta Sexual , Enfermedades Urológicas/complicacionesRESUMEN
Computerized dosimetric studies of single- and double-plane iridium-192 (Ir-192) planar implants were performed. With respect to dose homogeneity, we found that the optimal source and ribbon separation for single-plane implants was 1.0 cm. For double-plane implants, the preferred ribbon and plane separation was 1.5 cm, maintaining a 1-cm separation for the sources. Using these separations, standard dose rate curves for single- and double-plane Ir-192 implants were generated by computer calculations. These standard curves are useful for quickly and fairly accurately estimating the dose from any size planar implant, without requiring more time-consuming individual computer dosimetry. We believe that the curves will prove to be of practical clinical value to physicists and radiotherapists.
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Braquiterapia/métodos , Iridio/administración & dosificación , Radioisótopos/administración & dosificación , Dosificación RadioterapéuticaRESUMEN
Pancreatic cancer continues to have a dismal prognosis despite multimodality treatment plans. Peptide YY (PYY) is a gut hormone that suppresses pancreatic exocrine and endocrine function. Previous experiments have shown that shortened synthetic PYY(22-36) analog decreases pancreatic cancer cell growth while also decreasing intracellular cyclic adenosine monophosphate. Our purpose was to construct an optimal synthetic PYY analog that binds to pancreatic cancer cells that may be used for imaging and therapy. Biotinylated PYY analogs with lengths ranging from PYY(1-36), PYY(9-36), PYY(14-36), PYY(22-36), and PYY(27-36) were tested with flow cytometry and receptor cross-linking studies to measure cell membrane binding. Growth inhibition studies were also performed using monotetrazolium tests to determine potency of various PYY analogs. Quantitative flow cytometry reveals the highest specific binding of PYY(14-36) to pancreatic cancer cells. Cross-linking studies reveal a receptor on the cell membrane of human pancreatic ductal adenocarcinoma cells. Growth inhibition studies reveal that PYY (14-36) has the highest potency against PANC-1 and MiaPaCa-2 cells. A novel synthetic PYY analog binds to the cell surface of pancreatic cancer cells and has the ability to deliver fluorescent dyes. The strategy of using biotinylated peptides to deliver avidin-dye complexes to cancer cells will allow imaging of pancreatic tumors and delivery of therapeutic agents.
Asunto(s)
Carcinoma Ductal Pancreático/metabolismo , Colorantes Fluorescentes , Neoplasias Pancreáticas/metabolismo , Fragmentos de Péptidos/metabolismo , Péptido YY/metabolismo , Receptores de Superficie Celular/metabolismo , Biotinilación , Citometría de Flujo , Humanos , Células Tumorales CultivadasRESUMEN
A two-stage ileoanal pullthrough procedure (IAPP) is often used for patients with ulcerative colitis (UC) requiring proctocolectomy. We analyzed the recent University of California at Los Angeles experience with diverting end and loop ileostomies in patients undergoing a two-stage IAPP. A retrospective analysis of 21 patients with UC undergoing loop ileostomy between March 1992 and March 1995 was performed. Comparison was made with 21 age- and gender-matched patients undergoing end ileostomy between January 1991 and December 1995. There was no mortality or major septic complications. A second laparotomy was required in all patients with end ileostomies, whereas loop ileostomies were closed without abdominal exploration. During ileostomy closure, operative time and mean hospital stay were significantly reduced with the use of loop ileostomy. The time to oral feeding was not significantly different between end and loop ileostomy groups after ileostomy closure. The complication rate after IAPP was similar between groups. However, after ileostomy closure, the complication rate was significantly reduced with the use of loop ileostomy. We conclude that loop ileostomy is a desirable option for UC patients undergoing intestinal diversion during IAPP. Loop ileostomies can be created easily and without an increase in operative time. Subsequent ileostomy closure can be performed as a local procedure, which may shorten operative time and length of hospital stay.
Asunto(s)
Colitis Ulcerosa/cirugía , Ileostomía/métodos , Complicaciones Posoperatorias/cirugía , Proctocolectomía Restauradora/métodos , Adolescente , Adulto , Niño , Femenino , Estudios de Seguimiento , Humanos , Tiempo de Internación , Masculino , Persona de Mediana Edad , Reoperación , Resultado del TratamientoRESUMEN
Isolated dog neutrophils exposed to known chemotactic factors assumed a bipolar configuration in suspension. This response was initiated within 2 minutes with a gradual return to spherical shape. The rate of return to sphere was positively correlated with the dose of stimulant. Dog neutrophils exposed to N-formylmethionyl-leucyl-phenylalanine (fMLP) did not adapt to bipolar conformation and did not bind radiolabeled fMLP. These findings are consistent with other species (pig and cow) that also did not respond to fMLP.
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Perros/sangre , N-Formilmetionina Leucil-Fenilalanina/farmacología , Neutrófilos/fisiología , Animales , Quimiotaxis de Leucocito/efectos de los fármacos , Enfermedades de los Perros/sangre , Femenino , Humanos , Masculino , N-Formilmetionina Leucil-Fenilalanina/metabolismo , Neutrófilos/citología , Neutrófilos/efectos de los fármacos , Receptores de Formil Péptido , Receptores Inmunológicos/metabolismo , Sepsis/sangre , Sepsis/veterinaria , Especificidad de la EspecieRESUMEN
UNLABELLED: This study evaluated the feasibility of determining effective renal plasma flow (ERPF) at an off-site central laboratory by transferring blood samples from the on-site laboratory. METHODS: Blood samples were obtained from 66 patients referred for renal imaging with 99mTc-MAG3. ERPF values were determined using the single blood sample method (BSM) at both on- and off-site laboratories. The ERPF values were classified clinically as normal or abnormal. Both the ERPF values and clinical classification were compared between on- and off-site laboratories. RESULTS: The off-site ERPF overestimated those on-site by 2.8% (paired Student's t-test p < 10(-5)). However, off-site ERPF values highly correlated with the values obtained on-site (r = 0.99; p < 10(-5)). In addition, the clinical classification for each patient determined at each site was identical. CONCLUSION: ERPF can be determined accurately off-site. This method should allow many nuclear medicine departments access to the ERPF determination by the BSM at a central off-site laboratory.