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2.
Am J Physiol Lung Cell Mol Physiol ; 309(12): L1410-9, 2015 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-26498249

RESUMEN

Transendothelial hyperpermeability caused by numerous agonists is dependent on heat shock protein 90 (Hsp90) and leads to endothelial barrier dysfunction (EBD). Inhibition of Hsp90 protects and restores transendothelial permeability. Hyperacetylation of Hsp90, as by inhibitors of histone deacetylase (HDAC), suppresses its chaperone function and mimics the effects of Hsp90 inhibitors. In this study we assessed the role of HDAC in mediating lipopolysaccharide (LPS)-induced transendothelial hyperpermeability and acute lung injury (ALI). We demonstrate that HDAC inhibition protects against LPS-mediated EBD. Inhibition of multiple HDAC by the general inhibitors panobinostat or trichostatin provided protection against LPS-induced transendothelial hyperpermeability, acetylated and suppressed Hsp90 chaperone function, and attenuated RhoA activity and signaling crucial to endothelial barrier function. Treatment with the HDAC3-selective inhibitor RGFP-966 or the HDAC6-selective inhibitor tubastatin A provided partial protection against LPS-mediated transendothelial hyperpermeability. Similarly, knock down of HDAC3 and HDAC6 by specific small-interfering RNAs provided significant protection against LPS-induced EBD. Furthermore, combined pharmacological inhibition of both HDAC3 and -6 attenuated the inflammation, capillary permeability, and structural abnormalities associated with LPS-induced ALI in mice. Together these data indicate that HDAC mediate increased transendothelial hyperpermeability caused by LPS and that inhibition of HDAC protects against LPS-mediated EBD and ALI by suppressing Hsp90-dependent RhoA activity and signaling.


Asunto(s)
Lesión Pulmonar Aguda/tratamiento farmacológico , Permeabilidad Capilar/efectos de los fármacos , Células Endoteliales/efectos de los fármacos , Proteínas HSP90 de Choque Térmico/metabolismo , Inhibidores de Histona Desacetilasas/farmacología , Acetilación/efectos de los fármacos , Lesión Pulmonar Aguda/metabolismo , Animales , Células Cultivadas , Células Endoteliales/metabolismo , Endotelio Vascular/efectos de los fármacos , Endotelio Vascular/metabolismo , Histona Desacetilasas/metabolismo , Humanos , Lipopolisacáridos/farmacología , Pulmón/efectos de los fármacos , Pulmón/metabolismo , Ratones , Ratones Endogámicos C57BL
3.
Cureus ; 11(1): e3883, 2019 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-30899634

RESUMEN

Cerebrospinal fluid (CSF) rhinorrhea is most commonly associated with preceding trauma. Spontaneous CSF rhinorrhea has rarely been documented. Clinical, biochemical, and radiological examination are necessary to establish its diagnosis. Detection of beta-2 transferrin in watery nasal discharge is diagnostic for the presence of CSF. Computed tomography (CT) cisternography or magnetic resonance imaging (MRI) cisternogram are confirmatory radiologic modalities for localization of the leakage site.

4.
Cureus ; 11(8): e5445, 2019 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-31632890

RESUMEN

Parathyroid autotransplantation is an increasingly common procedure given the increasing rate of hyperparathyroidism. However, post-autotransplantation imaging is not commonly performed and the imaging findings can mimic liposarcoma. Therefore, radiologists should be aware of the imaging characteristics of parathyroid autotransplantation. Here we discuss the CT and Tc99m-Sestamibi 4D-CT findings of parathyroid autotransplantation. We will also discuss the pathophysiology of liposarcoma and present the gross histological findings seen on pathology.

5.
Sci Rep ; 9(1): 13967, 2019 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-31562359

RESUMEN

The interaction of ionizing radiation with matter is of critical importance in numerous areas of science and technology like space and vacuum technology and even medicine and biotechnology. Secondary electron emission is a consequence of electron irradiation on materials. We achieve extremely low secondary electron emission yield values smaller than 0.2, even up to incident electron energies ~1 keV, due to an undocumented synergy between neighbouring metal and dielectric domains in composite samples. To investigate this experimental discovery, we propose a simple 3D model where the dielectric and metallic domains are arranged in parallel and interleaved. The proposed surface profile has a triangular shape to model the surface roughness. We obtain a continuous equation to describe the electric field that arises between grounded conductors and charged dielectrics domains. The calculated trajectories of secondary electrons in this 3D geometry are used to predict dynamic secondary emission yield, which strongly depends on the charge accumulated in the dielectric domains. This research paves the way to design new materials of low secondary emission yield, addressing the technological problem not yet resolved to inhibit the electron avalanche in RF equipment that limit their maximum working power.

6.
Radiol Clin North Am ; 57(5): 883-896, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31351539

RESUMEN

Acute shoulder injury is commonly encountered by clinicians, surgeons, and radiologists. A comprehensive evaluation of the shoulder by the radiologist is essential to accurately relay findings that have a direct impact on acute and long-term management. In this review, imaging features of acute injuries involving the proximal humerus, glenohumeral joint, rotator cuff, tendon of the long head of the biceps brachii, and acromioclavicular joint are discussed. Modalities include ultrasound examination, conventional radiography, computed tomography scans, and MR imaging. Emphasis is placed on radiographic features that have an impact on patient management.


Asunto(s)
Diagnóstico por Imagen/métodos , Lesiones del Hombro/diagnóstico por imagen , Enfermedad Aguda , Humanos , Imagen por Resonancia Magnética , Lesiones del Hombro/terapia , Tomografía Computarizada por Rayos X , Ultrasonografía
7.
Cureus ; 10(11): e3653, 2018 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-30723652

RESUMEN

Esthesioneuroblastoma, also known as olfactory neuroblastoma, is a malignant tumor of the upper nasal cavity. This report illustrates the case of a 63-year-old woman who presented with intractable headaches. Subsequent radiologic evaluation and correlation with histopathologic analysis confirmed esthesioneuroblastoma. We review herein the typical computed tomographic (CT) and magnetic resonance (MR) imaging findings related to this locally destructive tumor, the prompt diagnosis of which may help prevent long-term morbidity and potentially, mortality. Up-to-date diagnostic criteria, staging, and management considerations are also outlined.

8.
Cureus ; 10(12): e3725, 2018 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-30800536

RESUMEN

Sporadic Creutzfeldt-Jakob disease (CJD) is the most common prion disease, resulting in rapid neurocognitive decline, and is universally lethal. CJD has a confounding clinical presentation with similarities which overlap with many other neurodegenerative disorders. Brain biopsy is the current gold standard; however, less-invasive initial screening tests are also utilized. These include brain magnetic resonance imaging (MRI), electroencephalography (EEG), and cerebrospinal fluid (CSF) laboratory studies. Five patients presented to our facility with varying levels of nonspecific cognitive impairment and movement disorders. CJD was initially suggested after review of each patient's brain MRI. The T2-weighted fluid attenuation inversion recovery and diffusion-weighted images in each case demonstrated varied classic patterns of signal abnormality involving the cortex, basal ganglia, thalami, and brainstem. EEG and CSF studies were confirmatory in three and four patients, respectively (EEG not performed in one patient). One death occurred two months after initial presentation, and the other four patients were transferred to hospice three, four, nine, and 20 months after initial presentation. Radiological evaluation is an invaluable component of the workup for nonspecific neurodegenerative disorders because brain MRI may suggest the initial diagnosis of CJD, as demonstrated in our presented cases. Familiarity with the spectrum of classic MRI findings suggestive of sporadic CJD can improve radiologists' role in early detection of the most common prion disease. Clinicians may benefit from understanding the utility of the newer CSF laboratory studies (Real-time quaking-induced conversion, T-tau, and 14-3-3 protein), which are far less invasive than the gold standard of brain biopsy. Early diagnosis can help save medical resources and guide clinicians to form appropriate plans of care with the patient and family.

9.
Arch Oral Biol ; 47(10): 743-7, 2002 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-12356506

RESUMEN

This study investigated the path of emergence of the mental nerve in a number of human population groups. Skeletal material comprised 117 Negro skulls (53 males), 114 caucasoid skulls (62 males) and 100 pre-contact Maori skulls (70 males). In each case, the path of emergence was classified into posterior, anterior, right-angled or multiple. Those cases with severely resorbed alveolar ridges that made classification difficult were excluded from the study. Additionally, 56 cadaveric mandibles were examined, in which an osteotomy of 1cm was made on either side of the mental foramen to expose the nerve. The most common pattern of emergence in caucasoids and Maoris was a posterior direction (86.7% of caucasoid males, 90.2% of caucasoid females; 85.5% of Maori males, 93.1% of Maori females). In Negroes the most common pattern was a right-angled path of emergence (45.8% of males, 45.0% of females), with this difference between population groups being statistically significant (Pearson's chi(2): males=23.4, females=45-97; P<0.01). Multiple foramina were rare, with the highest incidence being in Maori and Negro males. Cadaveric data supported the findings of the skeletal investigation, with the dominant emergence recorded as posteriorly directed (80.7% of males, 86.6% of females). It was concluded that while the traditionally accepted ontogenetic explanation for the inclination of the mental nerve might be applicable to caucasoids and Maoris, it fails to explain the observed right-angled emergence pattern in Negroes. Hence, the nerve's emergence might be genetically, rather than functionally, determined. The study did not show a measurable anterior loop in the emergence of the mental nerve that would have any significant impact on treatment planning for implants in the anterior mandible.


Asunto(s)
Nervios Craneales/anatomía & histología , Mandíbula/anatomía & histología , Vías Nerviosas/fisiología , Grupos Raciales , Anciano , Anciano de 80 o más Años , Población Negra , Implantes Dentales , Femenino , Humanos , Incisivo , Masculino , Mandíbula/inervación , Nativos de Hawái y Otras Islas del Pacífico , Población Blanca
11.
Homo ; 63(6): 407-12, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23107933

RESUMEN

Brown (2012: LB1 and LB6 Homo floresiensis are not modern human (Homo sapiens) cretins, Journal of Human Evolution) makes errors of fact, omission and interpretation. Brown's comments refer, among others, to (1) delayed growth and development indicated by unfused epiphyses, (2) postcranial limb proportions: limbs to trunk, between limbs, and within limbs, (3) postcranial bone torsions and angles, (4) postcranial robusticity, real and apparent, (5) skull features, and (6) cretinism on Flores. In each of these areas, much information about cretins is incorrect and much information (Oxnard et al., 2010) comparing the Liang Bua remains with cretins is ignored.


Asunto(s)
Hipotiroidismo Congénito/historia , Fósiles , Hominidae/anatomía & histología , Animales , Desarrollo Óseo , Huesos/patología , Hipotiroidismo Congénito/patología , Historia Antigua , Humanos , Cráneo/patología
12.
Artículo en Inglés | MEDLINE | ID: mdl-19836710

RESUMEN

OBJECTIVE: The most recent study of the relationship between the maxillary artery and the lateral pterygoid muscle was published in this journal in 2008.(1) Given the controversy surrounding this relationship, our purpose was to present data gathered from New Zealand caucasoid cadavers over several years. STUDY DESIGN: Both sides of 92 caucasoid adult cadaveric heads (45 male, 47 female) were dissected by 3 successive years of third-year medical students and second-year dental students. The infratemporal approach was used. Once the dissections reached the plane of the maxillary artery and lateral pterygoid muscle, their relationship was recorded, together with exemplary images. Sexual and symmetrical differences were noted. RESULTS: In the 53 cases where bilateral dissection had been successful, the second part of the maxillary artery was found superficial to the lower head of the lateral pterygoid muscle in 30 cases (57%)-in 70% of the males and 39% of the females. One male and 1 female presented bilateral asymmetry. CONCLUSIONS: The finding of 2 cases of bilateral asymmetry among the 53 bilaterally dissected cadavers led to the consideration of each "hemi-head" as a single entity. This increased the sample size. Statistical analysis of the data, systematically broken down by sex and by side, showed that the second part of the maxillary artery is more likely to lie deep to the lower head of the lateral pterygoid muscle in females than in males, and that "side" is irrelevant.


Asunto(s)
Arteria Maxilar/anatomía & histología , Músculos Pterigoideos/anatomía & histología , Adulto , Anciano , Anciano de 80 o más Años , Cadáver , Femenino , Humanos , Masculino , Nueva Zelanda , Factores Sexuales , Población Blanca
13.
Anthropol Anz ; 65(4): 353-63, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18196760

RESUMEN

The chance discovery of a paper by Rottstock et al. (1983) comparing the individual diameters of 4,497 teeth from 711 skulls from anthropologically-different populations (Europeans, Negroids, Mongoloids, Melanesians) provided the impetus to add our measurements of 449 teeth from 89 Polynesians (mainland Maoris, Chatham Island, Wairau Bar) to the series. We confirm that dental measurements provide clear differences among the different population groups. We confirm that dental indices are useful by disclosing specific dental relationships among the different population groups.


Asunto(s)
Antropometría/métodos , Dentición , Odontometría/métodos , Diente/anatomía & histología , Población Blanca , Humanos , Polinesia/etnología
14.
Anthropol Anz ; 65(3): 241-52, 2007 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17987904

RESUMEN

We noted the similarity in mandibular profile between a 27,000-year-old skull from China and a 160-year-old Polynesian skull. Both had a more vertical ramus, a curved inferior border, and no chin. The European mandible has a greater gonial angle, an antegonial notch, and a chin. Is the presence of a chin sufficient to distinguish European mandible from Polynesian? Can the gonial angle and ramus shape do so? A blind study of fifty mandibles of both groups and both sexes revealed that each feature alone can differentiate the sexes, but the combination is required, to differentiate European and Polynesian, and loosely group their provenances.


Asunto(s)
Mentón/anatomía & histología , Mandíbula/anatomía & histología , Población Blanca/historia , Cefalometría , China , Femenino , Historia del Siglo XX , Historia Antigua , Humanos , Masculino , Paleopatología , Polinesia , Tomografía Computarizada por Rayos X
15.
Anthropol Anz ; 63(2): 129-40, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15962565

RESUMEN

A sample of pre-European Polynesian and Melanesian mandibles, modern Asian Indians and cadaveric European mandibles were investigated to establish the prevalence of a subcondylar tubercle and to attempt to relate its presence to mandibular function. Among the three population samples, the subcondylar tubercle appeared 1.5 times more frequently among the Polynesians/Melanesians, than either the Indian or European groups. It was fairly equally present on both sides in all three groups. Where it was present unilaterally, it was far more likely to be present on the left side. This left-side presence coincided with a significantly greater right-side condylar height and ramal width.


Asunto(s)
Antropología/métodos , Antropometría/métodos , Cóndilo Mandibular/anatomía & histología , Adulto , Evolución Biológica , Cadáver , Europa (Continente)/epidemiología , Humanos , Incidencia , India/epidemiología , Polinesia/epidemiología , Factores Sexuales
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