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1.
G Chir ; 38(6): 303-312, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29442063

RESUMEN

BACKGROUND: Many studies have elaborated different kind of activity indices for Crohn's Disesase (CD) with the endpoint of univocally measure and evaluate the gravity of its lesions and symptoms. AIM: Purpose of this work is to study and define the correlation that runs between the preoperative score obtained at the Crohn's Disease Activity Index, the occurrence of postoperative complications that will require re-intervention and the severity of the postoperative lesions evaluated using the Clavien-Dindo score. PATIENTS AND METHODS: We have collected and analyzed data from 23 patients (12 males, 11 females) that in a period that spans from 2010 to 2016 had been recovered in our Operative Unit and then undergone surgical treatment for the perforative complications of the CD. RESULTS: The CDAI scores obtained for each patient and the data concerning their postoperative period have been analyzed using the ANOVA system. Results demonstrate the existence of a statistically signifying correlation (p = 0.0016) between the mean category's CDAI score and the Clavien-Dindo classification. CONCLUSIONS: Despite the small number of patients that had been recruited and analyzed in our study, it clearly shows a statistically signifying correlation between CDAI scores higher than 150 points and the risk of occurrence of severe postoperative complications in patients that had been subjected to surgical procedures for perforative or abscessual complications in Crohn's Disease.


Asunto(s)
Enfermedad de Crohn/complicaciones , Perforación Intestinal/etiología , Perforación Intestinal/cirugía , Complicaciones Posoperatorias/epidemiología , Adulto , Femenino , Humanos , Masculino , Índice de Severidad de la Enfermedad
2.
Nat Med ; 4(10): 1157-65, 1998 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9771749

RESUMEN

Variations in prions, which cause different incubation times and deposition patterns of the prion protein isoform called PrP(Sc), are often referred to as 'strains'. We report here a highly sensitive, conformation-dependent immunoassay that discriminates PrP(Sc) molecules among eight different prion strains propagated in Syrian hamsters. This immunoassay quantifies PrP isoforms by simultaneously following antibody binding to the denatured and native forms of a protein. In a plot of the ratio of antibody binding to denatured/native PrP graphed as a function of the concentration of PrP(Sc), each strain occupies a unique position, indicative of a particular PrP(Sc) conformation. This conclusion is supported by a unique pattern of equilibrium unfolding of PrP(Sc) found with each strain. Our findings indicate that each of the eight prion strains has a PrP(Sc) molecule with a unique conformation and, in accordance with earlier results, indicate the biological properties of prion strains are 'enciphered' in the conformation of PrP(Sc) and that the variation in incubation times is related to the relative protease sensitivity of PrP(Sc) in each strain.


Asunto(s)
Inmunoensayo/métodos , Proteínas PrPSc/química , Animales , Encéfalo/patología , Química Encefálica , Precipitación Química , Cricetinae , Mesocricetus , Fragmentos de Péptidos/química , Fragmentos de Péptidos/inmunología , Ácido Fosfotúngstico , Proteínas PrPSc/clasificación , Proteínas PrPSc/inmunología , Enfermedades por Prión/diagnóstico , Conformación Proteica , Desnaturalización Proteica
3.
Science ; 279(5352): 827-34, 1998 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-9452375

RESUMEN

At the endoplasmic reticulum membrane, the prion protein (PrP) can be synthesized in several topological forms. The role of these different forms was explored with transgenic mice expressing PrP mutations that alter the relative ratios of the topological forms. Expression of a particular transmembrane form (termed CtmPrP) produced neurodegenerative changes in mice similar to those of some genetic prion diseases. Brains from these mice contained CtmPrP but not PrPSc, the PrP isoform responsible for transmission of prion diseases. Furthermore, in one heritable prion disease of humans, brain tissue contained CtmPrP but not PrPSc. Thus, aberrant regulation of protein biogenesis and topology at the endoplasmic reticulum can result in neurodegeneration.


Asunto(s)
Retículo Endoplásmico/metabolismo , Enfermedades Neurodegenerativas/etiología , Proteínas PrPC/química , Proteínas PrPC/metabolismo , Priones/química , Priones/metabolismo , Secuencia de Aminoácidos , Animales , Encéfalo/metabolismo , Encéfalo/patología , Cricetinae , Endopeptidasas/metabolismo , Retículo Endoplásmico/química , Enfermedad de Gerstmann-Straussler-Scheinker/metabolismo , Humanos , Membranas Intracelulares/química , Mesocricetus , Ratones , Ratones Transgénicos , Datos de Secuencia Molecular , Mutación , Enfermedades Neurodegenerativas/metabolismo , Enfermedades Neurodegenerativas/patología , Proteínas PrPC/biosíntesis , Proteínas PrPC/genética , Proteínas PrPSc/química , Proteínas PrPSc/metabolismo , Enfermedades por Prión/etiología , Enfermedades por Prión/metabolismo , Enfermedades por Prión/patología , Priones/biosíntesis , Priones/genética , Conformación Proteica
4.
Neuron ; 7(1): 59-68, 1991 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-1676894

RESUMEN

Prolonged incubation times for experimental scrapie in I/LnJ mice are dictated by a dominant gene linked to the prion protein gene (Prn-p). Transgenic mice were analyzed to discriminate between an effect of the I/LnJ Prn-pb allele and a distinct incubation time locus designated Prn-i. Paradoxically, 4 independent Prn-pb transgenic mouse lines had scrapie incubation times shorter than nontransgenic controls, instead of the anticipated prolonged incubation periods. Aberrant or overexpression of the Prn-pb transgenes may dictate abbreviated incubation times, masking genuine Prn-p/Prn-i congruence; alternatively, a discrete Prn-i gene lies adjacent to Prn-p.


Asunto(s)
Expresión Génica , Scrapie/fisiopatología , Proteínas Virales/genética , Animales , Encéfalo/metabolismo , Ratones , Ratones Transgénicos , Proteínas PrPSc , Priones/genética , Priones/metabolismo , ARN Mensajero/metabolismo , Factores de Tiempo , Proteínas Virales/metabolismo
5.
Neuron ; 19(6): 1337-48, 1997 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9427256

RESUMEN

The pattern of scrapie prion protein (PrP(Sc)) accumulation in the brain is different for each prion strain. We tested whether the PrP(Sc) deposition pattern is influenced by the Asn-linked oligosaccharides of PrP(C) in transgenic mice. Deletion of the first oligosaccharide altered PrP(C) trafficking and prevented infection with two prion strains. Deletion of the second did not alter PrP(C) trafficking, permitted infection with one prion strain, and had a profound effect on the PrP(Sc) deposition pattern. Our data raise the possibility that glycosylation can modify the conformation of PrP(C). Glycosylation could affect the affinity of PrP(C) for a particular conformer of PrP(Sc), thereby determining the rate of nascent PrP(Sc) formation and the specific patterns of PrP(Sc) deposition.


Asunto(s)
Encéfalo/metabolismo , Proteínas PrPC/biosíntesis , Enfermedades por Prión/metabolismo , Animales , Encéfalo/patología , Cricetinae , Mesocricetus , Ratones , Ratones Transgénicos , Mutagénesis , Oligosacáridos/metabolismo , Sistemas de Lectura Abierta , Especificidad de Órganos , Proteínas PrPC/química , Proteínas PrPC/genética , Enfermedades por Prión/patología , Eliminación de Secuencia
6.
Mol Cell Biol ; 8(12): 5528-40, 1988 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-3149717

RESUMEN

The mouse prion protein (PrP) gene (Prn-p), which encodes the only macromolecule that has been identified in scrapie prions, is tightly linked or identical to a gene (Prn-i) that controls the duration of the scrapie incubation period in mice. Constellations of restriction fragment length polymorphisms distinguish haplotypes a to f of Prn-p. The Prn-pb allele encodes a PrP that differs in sequence from those encoded by the other haplotypes and, in inbred mouse strains, correlates with long scrapie incubation time (Westaway et al., Cell 51: 651-662, 1987). In segregating crosses of mice, we identified rare individuals with a divergent scrapie incubation time phenotype and Prn-p genotype, but progeny testing to demonstrate meiotic recombination was not possible because scrapie is a lethal disease. Crosses involving the a, d, and e haplotypes demonstrated that genes unlinked to Prn-p could modulate scrapie incubation time and that there were only two alleles of Prn-i among the mouse strains tested. All inbred strains of mice that had the Prnb haplotype were probably direct descendants of the I/LnJ progenitors. We established the linkage relationship between the prion gene complex (Prn) and other chromosome 2 genes; the gene order, proximal to distal, is B2m-II-1a-Prn-Itp-A. Recombination suppression in the B2m-Prn-p interval occurred during the crosses involved in transferring the I/LnJ Prnb complex into a C57BL/6J background. Transmission ratio distortion by Prna/Prnb heterozygous males was also observed in the same crosses. These phenomena, together with the founder effect, would favor apparent linkage disequilibrium between Prn-p and Prn-i. Therefore, transmission genetics may underestimate the number of genes in Prn.


Asunto(s)
Genes Virales , Genes , Polimorfismo Genético , Priones/genética , Proteínas Virales/genética , Animales , Southern Blotting , Cruzamientos Genéticos , Ligamiento Genético , Cinética , Ratones , Ratones Endogámicos , Especificidad de la Especie
7.
Int J Oral Maxillofac Surg ; 36(8): 712-5, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17391918

RESUMEN

The objective of this study was to assess the anatomical variation of the marginal mandibular nerve, and evaluate the risk of nerve malfunction after neck dissection. The method involved clinical assessment of the anatomy and function of the marginal mandibular nerve in 133 neck dissections. When the neck was extended the nerve was displaced in an anterior and downward direction with the lowest point 1.25+/-0.7 cm below the mandible between the posterior and anterior facial veins. The nerve was >1cm below the lower border of the mandible in 54% of dissections. When the intent was to preserve the nerve, dysfunction was observed in 16 of 101 dissections (16%). The incidence of marginal mandibular nerve dysfunction following neck dissection is comparable to that observed following submandibular gland excision for benign disease. Placement of incisions 2 cm below the lower border of the mandible will put the nerve at risk in a significant number of patients.


Asunto(s)
Mandíbula/anatomía & histología , Nervio Mandibular/anatomía & histología , Disección del Cuello/efectos adversos , Distribución de Chi-Cuadrado , Traumatismos del Nervio Facial/prevención & control , Femenino , Humanos , Masculino , Mandíbula/inervación , Persona de Mediana Edad , Análisis Multivariante , Disección del Cuello/métodos , Traumatismos del Nervio Trigémino
8.
J Mol Biol ; 295(4): 997-1007, 2000 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-10656806

RESUMEN

The molecular basis of the infectious, inherited and sporadic forms of prion diseases is best explained by a conformationally dimorphic protein that can exist in distinct normal and disease-causing isoforms. We identified a 55-residue peptide of a mutant prion protein that can be refolded into at least two distinct conformations. When inoculated intracerebrally into the appropriate transgenic mouse host, 20 of 20 mice receiving the beta-form of this peptide developed signs of central nervous system dysfunction at approximately 360 days, with neurohistologic changes that are pathognomonic of Gerstmann-Sträussler-Scheinker disease. By contrast, eight of eight mice receiving a non-beta-form of the peptide failed to develop any neuropathologic changes more than 600 days after the peptide injections. We conclude that a chemically synthesized peptide refolded into the appropriate conformation can accelerate or possibly initiate prion disease.


Asunto(s)
Encéfalo/patología , Enfermedad de Gerstmann-Straussler-Scheinker/genética , Fragmentos de Péptidos/química , Priones/genética , Secuencia de Aminoácidos , Animales , Encéfalo/efectos de los fármacos , Enfermedad de Gerstmann-Straussler-Scheinker/patología , Enfermedad de Gerstmann-Straussler-Scheinker/fisiopatología , Humanos , Ratones , Ratones Transgénicos , Datos de Secuencia Molecular , Fragmentos de Péptidos/administración & dosificación , Fragmentos de Péptidos/toxicidad , Priones/química , Conformación Proteica , Pliegue de Proteína , Estructura Secundaria de Proteína , Scrapie/patología , Espectroscopía Infrarroja por Transformada de Fourier
9.
Genetics ; 133(4): 979-88, 1993 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8462855

RESUMEN

Scrapie is a transmissible neurodegenerative disease caused by unusual pathogens called prions. The interval between inoculation and illness for experimental mouse scrapie is dramatically influenced by an incubation time gene (Prn-i) that is linked to Prn-p, the structural gene for prion protein (PrP). Although prion proteins from mouse strains with short and long scrapie incubation times differ by two amino acids, mice with discordant disease phenotype and Prn-p genotype occur in segregating crosses, suggesting recombination between Prn-p and a distinct incubation time locus. In addition, expression of Prn-pb transgenes from long incubation time mice shortened, rather than prolonged, incubation time. In this study, mice carrying chromosomes with meiotic crossovers near Prn-p were analyzed for scrapie incubation time phenotype. The results indicated that Prn-i (should it exist) must lie within an interval 0.67 cM proximal and 0.22 cM distal to Prn-p. The results also suggest that the cumulative effects of other genes, rather than meiotic recombination, were responsible for the putative recombinants of earlier studies. However, the effect of Prn-pb transgene expression in abbreviating scrapie incubation time was mitigated when the transgenes were transferred to mice with an endogenous long incubation time allele. Thus, Prn-pb transgenes and Prn-i may modulate scrapie pathogenesis by different mechanisms.


Asunto(s)
Mapeo Cromosómico , Genes Virales , Priones/genética , Scrapie/microbiología , Alelos , Animales , Ratones , Ratones Endogámicos C57BL , Recombinación Genética , Factores de Tiempo , Proteínas Estructurales Virales/genética
10.
Protein Sci ; 6(4): 825-33, 1997 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9098892

RESUMEN

The eight amino acid sequence, Asp-Tyr-Lys-Asp-Asp-Asp-Asp-Lys, representing the FLAG peptide, was inserted after codons 22 or 88 of the mouse (Mo) prion protein (PrP) gene. Inclusion of the FLAG sequence at these locations interfered neither with the cellular processing of PrPC nor its conversion into PrPSc. Inclusion of the FLAG epitope at residue 22 but not at residue 88 facilitated immunodetection of tagged PrP by anti-FLAG monoclonal antibodies (mAbs). Inoculation of transgenic (Tg) mice expressing N-terminally tagged MoPrP with Mo prions resulted in abbreviated incubation times, indicating that the FLAG sequence was not deleterious to prion propagation. Immunopurification of FLAG-tagged MoPrPC in the brains of Tg mice was achieved using the calcium-dependent anti-FLAG M1 mAb and non-denaturing procedures. Although the function of PrPC remains unknown, our studies demonstrate that some modifications of PrPC do not inhibit the one biological activity that can be measured, i.e., conversion into PrPSc. Tagged PrP molecules may prove useful in the development of improved assays for prions as well as structural studies of the PrP isoforms.


Asunto(s)
Priones/metabolismo , Animales , Encéfalo/metabolismo , Encéfalo/patología , Ratones , Ratones Transgénicos , Priones/química , Priones/aislamiento & purificación , Células Tumorales Cultivadas
11.
J Neuropathol Exp Neurol ; 58(12): 1244-9, 1999 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-10604749

RESUMEN

The kinetics of PrP(Sc) and insoluble PrP accumulation in the spleens and brains of CD-1 mice were studied. The mice were inoculated intracerebrally with RML prions and euthanized at various times between inoculation and the onset of illness at approximately 130 days. Protease-resistant PrP(Sc), PrP 27-30, was first detected in brain by histoblotting 49 days after inoculation and by Western immunoblotting at 70 days. In spleen, PrP 27-30 was first detected by Western immunoblotting at 28 days after inoculation. Like PrP 27-30, substantial increases in detergent-insoluble PrP were first detected at 70 days after inoculation in brain and 28 days in spleen. In addition, a progressive increase in detergent-soluble PrP was detected beginning 70 days after inoculation. Further characterization of detergent soluble and insoluble PrP with respect to protease-sensitive PrP(Sc) and prion infectivity will be of considerable interest.


Asunto(s)
Encéfalo/metabolismo , Priones/metabolismo , Scrapie/metabolismo , Animales , Western Blotting , Detergentes/farmacología , Cinética , Ratones , Proteína PrP 27-30/metabolismo , Proteínas PrPSc/metabolismo , Solubilidad , Bazo/metabolismo , Factores de Tiempo , Distribución Tisular
12.
Neurology ; 39(10): 1319-24, 1989 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-2507957

RESUMEN

Prions cause Creutzfeldt-Jakob disease, Gerstmann-Sträussler syndrome, and kuru of humans as well as scrapie of animals. Prolonged incubation periods, from months to decades, precede clinical disease. In studies on the biochemical characteristics of prions, weanling Syrian hamsters have been used extensively because they have relatively short incubation periods. In studies reported here, inoculation of neonatal hamsters significantly shortened the scrapie incubation period even further. Our results show that the scrapie incubation period in hamsters is a function of age. The interval between inoculation and death from scrapie plotted as a function of age (0 to 30 days) gave a correlation coefficient (r) of 0.86. The duration of clinical disease was also shortened in the hamsters inoculated as neonates compared with weanlings. Intraventricular injection of nerve growth factor prior to inoculation of neonates with scrapie significantly diminished the acceleration observed with scrapie alone in neonates. Histopathologic studies of brain from scrapie-inoculated neonates showed more extensive neuronal loss in the hippocampus and neocortex as well as a more profound gliosis in the caudate compared with animals inoculated as weanlings. Our results demonstrate an age-dependent acceleration of scrapie in neonatal hamsters and may provide a new experimental system for defining factors that modify the pathogenesis of prion diseases.


Asunto(s)
Scrapie/fisiopatología , Animales , Animales Recién Nacidos , Encéfalo/patología , Cricetinae , Inyecciones , Inyecciones Intraperitoneales , Mesocricetus , Factores de Crecimiento Nervioso/farmacología , Priones , Scrapie/patología , Factores de Tiempo
13.
Neurology ; 41(9): 1482-90, 1991 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-1679911

RESUMEN

Multiple lines of evidence indicate that PrPSc, found only in scrapie, is a necessary component of the infectious scrapie agent. Equally compelling is the evidence that its accumulation in the brain causes the neuropathology characteristic of scrapie. We measured the regional concentration of PrPSc in nine brain regions throughout the course of scrapie in the Syrian hamster following intrathalamic inoculation of prions. PrPSc was compared to the regional concentration of glial fibrillary acidic protein, a measure of reactive astrocytic gliosis. PrPSc was detected first in the thalamus 14 to 21 days postinoculation and next in the septum at 28 days. Initiation of PrPSc synthesis and accumulation in the thalamus was attributable to the inoculum and in the septum to ventricular spread of de novo synthesized PrPSc. The timing and pattern of PrPSc accumulation in all other brain regions suggested transmission along neuroanatomic pathways. Reactive astrocytic gliosis followed PrPSc accumulation in each region by 1 to 2 weeks. Brain PrPSc, determined by summing the concentrations in each brain region, correlated well with scrapie infectivity titers throughout the course of infection (correlation coefficient = 0.975; slope of linear regression line = 1.136). Our results support the hypothesis that PrPSc participates in both the etiology and pathogenesis of prion diseases.


Asunto(s)
Encéfalo/metabolismo , Scrapie/metabolismo , Proteínas Virales/metabolismo , Animales , Encéfalo/patología , Cricetinae , Proteína Ácida Fibrilar de la Glía/genética , Proteína Ácida Fibrilar de la Glía/metabolismo , Mesocricetus , Neuroglía/metabolismo , Hibridación de Ácido Nucleico , Proteínas PrPSc , ARN Mensajero/análisis , Scrapie/patología
14.
Mayo Clin Proc ; 74(8): 764-9, 1999 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10473351

RESUMEN

OBJECTIVE: To investigate the potential role of a store-and-forward (SAF) telemedicine system in specialty consultations initiated by primary care physicians. MATERIALS AND METHODS: In this pilot telemedicine study, patients needing consultations in cardiology, dermatology, endocrinology, and orthopedics had both standard face-to-face (FTF) consultations and SAF consultations. RESULTS: Fifteen patients had both FTF and SAF consultations, 4 had echocardiograms transmitted for an SAF consultation only, and 1 had an SAF consultation but no FTF appointment. Of 19 diagnoses made, all were essentially the same in both types of consultations; 14 of 15 FTF consultations and 15 of 19 SAF consultations resulted in additional treatment recommendations. CONCLUSIONS: While it was possible to develop a desktop system for SAF consultations, the equipment was not adequately integrated. Without total digital input, including electronic patient medical records, packaging of information is laborious and impractical. Seamlessly adapting to existing clinical practice is vital. Issues such as increasing work for the physicians or office staff, gathering adequate patient information, and designing a referral process were more difficult than we had anticipated. Patient acceptance was high, but the clinical pilot had very small numbers.


Asunto(s)
Consulta Remota/instrumentación , Consulta Remota/métodos , Femenino , Humanos , Masculino , Medicina , Proyectos Piloto , Método Simple Ciego , Programas Informáticos , Especialización , Evaluación de la Tecnología Biomédica , Telemedicina/instrumentación , Telemedicina/métodos , Estados Unidos
15.
Histol Histopathol ; 13(4): 1061-8, 1998 10.
Artículo en Inglés | MEDLINE | ID: mdl-9810502

RESUMEN

Many studies have demonstrated that allograft tolerance can be achieved in inbred rats and mice following intrathymic injection of donor cells or antigen and treatment with antilymphocyte serum (ALS). In outbred dogs, xenografts, and inbred rat strains with major MHC antigen difference, tolerance has not similarly been induced. The focus of this study was to determine whether allogeneic thyroid graft tolerance could be achieved in outbred rabbits. In the experimental group (n = 5), recipients received an intrathymic injection of donor lymphocytes and a single treatment of ALS. Controls (n = 5) received intrathymic cell culture medium and ALS treatment. Donor-recipient allogenicity was monitored with mixed lymphocyte culture (MLC) over 18 weeks. Donor thyroid tissue was placed into recipient gluteal muscle fibres one week following the last MLC measurement. A third group of rabbits (n = 4) received thyroid autografts without any other treatment. There were no differences in MLC stimulation indices (SI) between the control and experimental group nor did MLC (SI) change within groups. All thyroid autografts survived the two week monitoring period and demonstrated normal appearing thyroid follicles on histologic examination. All thyroid allografts showed severe acute rejection reactions on biopsy within one week. Further studies using outbred animals to examine the role of thymic inoculation are required to determine whether similar techniques might be successful in the human.


Asunto(s)
Tolerancia Inmunológica/inmunología , Timo/inmunología , Glándula Tiroides/inmunología , Glándula Tiroides/trasplante , Animales , Suero Antilinfocítico/inmunología , Células Cultivadas , Supervivencia de Injerto , Linfocitos/citología , Linfocitos/inmunología , Conejos , Timo/citología , Glándula Tiroides/ultraestructura , Trasplante Homólogo/inmunología
16.
Ann N Y Acad Sci ; 821: 76-82, 1997 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-9238195

RESUMEN

Although the impetus for studying hippocampal morphology and functioning in PTSD was the finding that stress could result in hippocampal damage in rodent and primate models, it is far from proven that the findings to date in PTSD represent defects that have been caused by trauma. It is equally possible that the findings represent a preexisting anomaly which might serve as a risk factor for the development of PTSD following trauma exposure. To resolve this dilemma, it is necessary to study persons at high risk for trauma (e.g., soldiers) prior to trauma exposure and ag in after exposure. Such methods will permit the determination not only of whether trauma alters hippocampal morphology, but also, if so, of whether this effect is limited to persons with PTSD. At the present time, the field would be well advised to proceed vigorously but with appropriate caution along these lines of research. As just outlined, sample sizes have been small, and potentially confounding variables have abounded in most studies. The next few years of research may well continue to replicate the finding of abnormal hippocampal morphology in PTSD. However, it would not be surprising to find that other brain regions are also involved and that these represent part of a broader risk spectrum for the development of psychopathology under stress. Until these issues are clarified, the neuroanatomical findings to date in PTSD should be viewed as tentative, tantalizing, and in need of additional study.


Asunto(s)
Encéfalo/patología , Trastornos por Estrés Postraumático/patología , Encéfalo/fisiopatología , Humanos , Trastornos por Estrés Postraumático/fisiopatología , Trastornos por Estrés Postraumático/psicología
17.
Obstet Gynecol ; 72(6): 841-6, 1988 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-3054650

RESUMEN

Biophysical profile scoring was the principal technique of antepartum fetal surveillance in 238 well-controlled diabetic pregnancies. Fifty insulin-dependent diabetics had twice-weekly testing, and 188 gestational diabetics had weekly testing. Intervention was not pursued unless there were maternal or fetal complications. There were no stillbirths and three neonatal deaths, all resulting from congenital anomalies, giving a corrected perinatal mortality rate of 0. The incidence of abnormal biophysical profile scores, eight of 238 (3.3%) overall, was low, with no significant difference between types of diabetics. In those with an abnormal score, intervention was mandated; the cesarean section rate was 50% and the rate of intensive care nursery admissions was high. Of the 230 fetuses with a normal biophysical profile score, 200 (87%) were delivered at term with minimal maternal or neonatal morbidity. Amniocentesis for phospholipid profile was performed in only 33 cases (13.9%). Hyaline membrane disease was confined to five premature neonates (incidence 2.1%). We conclude that antepartum fetal surveillance using the biophysical profile score permits safe expectant management in the diabetic pregnancy, yielding significant clinical advantages to both mother and fetus.


Asunto(s)
Feto/fisiología , Embarazo en Diabéticas , Ultrasonografía , Líquido Amniótico/análisis , Cesárea , Diabetes Mellitus Tipo 1 , Femenino , Movimiento Fetal , Humanos , Mortalidad Infantil , Recién Nacido , Trabajo de Parto Inducido , Embarazo , Resultado del Embarazo , Estudios Prospectivos , Respiración
18.
J Orthop Res ; 8(6): 883-91, 1990 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-2213345

RESUMEN

A quantitative assessment of cross-sectional cortical bone remodeling in the femoral diaphysis following hip arthroplasty was made by direct in vitro measurements of cross-sectional geometric properties. We obtained eight femora from four female cadavers ranging in age from 77 to 96 years. In three cases unilateral uncemented Austin Moore implants were used, and in one case a unilateral cemented Thompson prosthesis had been implanted. The time of implantation in the two specimens where this information could be obtained was greater than 40 months. Sections were made at 12 diaphyseal locations from the superior aspect of the lesser trochanter through the distal diaphysis. Section properties (areas and second moments of area, or area moments of inertia) were determined by tracing photographs of the cross-sections with a digitizer. In this sample of prosthetic femora, we found reductions in both total subperiosteal area (TA) and endosteal area (ENDA) relative to the contralateral unoperated side in most sections distal to the lesser trochanter. The average pairwise reduction in ENDA for this region was 21.1 mm2, reaching statistical significance in one distal diaphyseal section. The average decline in TA in this region was 10.2 mm2. Because the reduction in endosteal dimensions was generally greater than the reduction in subperiosteal dimensions, cortical area (CA) was maintained or increased throughout the distal 80% of this region in prosthetic femora with an average increase in CA of 9.3 mm2, reaching statistical significance in one mid-diaphyseal section. A completely different pattern of remodeling occurred in the two most proximal sections through the lesser trochanter and base of the femoral neck.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Fémur/fisiopatología , Prótesis de Cadera , Anciano , Anciano de 80 o más Años , Cadáver , Femenino , Fémur/patología , Humanos , Movimiento (Física) , Valores de Referencia
19.
AJNR Am J Neuroradiol ; 22(1): 143-51, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11158900

RESUMEN

BACKGROUND AND PURPOSE: Current imaging does not permit quantification of neural injury after traumatic brain injury (TBI) and therefore limits both the development of new treatments and the appropriate counseling of patients concerning prognosis. We evaluated the utility of magnetization transfer ratio (MTR) and proton MR spectroscopy in identifying patients with neuronal injury after TBI. METHODS: Thirty patients with TBI (21-77 years old; mean age, 42 years; admission Glasgow Coma Scale (GOS) scores 3-15; mean score, 11) were studied on a 1.5-T system with magnetization transfer imaging and MR spectroscopy of the splenium. Magnetization transfer imaging was also performed in the brain stem in all patients, and other areas of the brain were sampled in one patient. The splenium of the corpus callosum and brain stem were studied because these are often affected by diffuse axonal injury. Scans were obtained 2 to 1129 days after injury (median, 41 days). MTR was considered abnormal if it was more than 2 SD below normal. Proton MR spectroscopy was used to calculate the N-acetylaspartate (NAA)/creatine (Cr) ratio. GOS was determined at least 3 months after injury. RESULTS: In 10 patients with a GOS of 1 to 4, the mean NAA/Cr was 1.24 +/- 0.28; two of these patients had abnormal MTR in normal-appearing white matter (NAWM). In 20 patients with a GOS of 5, the mean NAA/Cr was 1.53 +/- 0.37 (P < .05); four of these patients had abnormal MTR in NAWM. MTR abnormalities in NAWM were identified in six patients, but these changes did not correlate with GOS or MR spectroscopy changes. CONCLUSION: MTR and MR spectroscopy can quantify damage after TBI, and NAA levels may be a sensitive indicator of the neuronal damage that results in a worse clinical outcome.


Asunto(s)
Ácido Aspártico/análogos & derivados , Axones/patología , Lesiones Encefálicas/diagnóstico , Encéfalo/patología , Imagen por Resonancia Magnética , Espectroscopía de Resonancia Magnética , Ácido Aspártico/metabolismo , Biomarcadores , Encéfalo/metabolismo , Lesiones Encefálicas/metabolismo , Lesiones Encefálicas/fisiopatología , Tronco Encefálico/patología , Cuerpo Calloso/patología , Creatina/metabolismo , Escala de Coma de Glasgow , Factores de Tiempo
20.
J Neurosurg ; 95(4): 595-600, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11596953

RESUMEN

OBJECT: The authors present their experience with the treatment of brain metastases from non-small cell lung carcinoma (NSCLC). METHODS: A retrospective review was conducted in which records from 74 patients treated at the authors' institution between 1994 and 1999 were assessed. Survival and functional outcome were reviewed relative to individual patient variables. The median survival time was 12.9 months, with 1-, 2-, and 5-year survival milestones reached by 52.2%, 30.7%. and 18.1% of patients, respectively. Patients were stratified into groups composed of those with synchronous brain metastases (tumors diagnosed within 3 months of NSCLC) and metachronous brain metastases (tumors diagnosed 3 months after NSCLC). The median survival time and 5-year survival rate were 18 months and 28.9% for metachronous, compared with 9.9 months and 0% for synchronous brain metastases. In univariate analyses, the stage of brain metastases, an initial Karnofsky Performance Scale (KPS) score of 90 or less, and conservative therapy for NSCLC were associated with worse outcomes (p < 0.05). In analyses in which tumors were stratified by synchronous compared with metachronous brain metastases, a preoperative KPS score of 90 or less and radiation therapy (RT) alone for brain metastases were associated with worse outcomes in patients with metachronous brain metastases but not with synchronous tumors (p < 0.05). When stratified by preoperative KPS score, the synchronous brain metastases stage or treatment of brain metastases with RT alone were associated with worse outcome in patients with KPS scores of 100, but had no discernible effect on patients with KPS scores of 90 or less (p < 0.05). CONCLUSIONS: The tumor stage and preoperative KPS score were significantly associated with survival. Craniotomy plus RT significantly improved the prognosis in patients with metachronous brain metastases or those with a preoperative KPS score of 100.


Asunto(s)
Neoplasias Encefálicas/secundario , Neoplasias Encefálicas/cirugía , Carcinoma de Pulmón de Células no Pequeñas/secundario , Carcinoma de Pulmón de Células no Pequeñas/cirugía , Neoplasias Pulmonares/patología , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias Encefálicas/fisiopatología , Carcinoma de Pulmón de Células no Pequeñas/fisiopatología , Femenino , Estudios de Seguimiento , Humanos , Estado de Ejecución de Karnofsky , Masculino , Persona de Mediana Edad , Factores de Riesgo , Análisis de Supervivencia
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