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1.
Skeletal Radiol ; 53(3): 409-417, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37566149

RESUMEN

The 2013 ISCD consensus recommended a Caucasian female reference database for T-score calculation in men, which says "A uniform Caucasian (non-race adjusted) female reference database should be used to calculate T-scores for men of all ethnic groups." However, this statement was recommended for the US population, and no position was taken with respect to BMD reference data or ethnicity matching outside of the USA. In East Asia, currently, a Japanese BMD reference database is universally adopted in Japan for clinical DXA diagnosis, while both local BMD and Caucasian BMD reference databases are in use in Mainland China, South Korea, Taiwan, and Singapore. In this article, we argue that an ethnicity- and gender-specific BMD database should be used for T-score calculations for East Asians, and we list the justifications why we advocate so. Use of a Caucasian BMD reference database leads to systematically lower T-scores for East Asians and an overestimation of the prevalence of osteoporosis. Using a female BMD reference database to calculate T-scores for male patients leads to higher T-score values and an underestimation of the prevalence of osteoporosis. Epidemiological evidence does not support using a female BMD reference database to calculate T-scores for men. We also note that BMD reference databases collected in Asia should be critically evaluated for their quality.


Asunto(s)
Densidad Ósea , Osteoporosis , Humanos , Masculino , Femenino , Etnicidad , Absorciometría de Fotón/métodos , Valores de Referencia , Osteoporosis/diagnóstico por imagen
2.
Skeletal Radiol ; 53(4): 609-625, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37889317

RESUMEN

The 1994 WHO criterion of a T-score ≤ -2.5 for densitometric osteoporosis was chosen because it results in a prevalence commensurate with the observed lifetime risk of fragility fractures in Caucasian women aged ≥ 50 years. Due to the much lower risk of fragility fracture among East Asians, the application of the conventional WHO criterion to East Asians leads to an over inflated prevalence of osteoporosis, particularly for spine osteoporosis. According to statistical modeling and when a local BMD reference is used, we tentatively recommend the cutpoint values for T-score of femoral neck, total hip, and spine to be approximately -2.7, -2.6, and -3.7 for Hong Kong Chinese women. Using radiographic osteoporotic vertebral fracture as a surrogate clinical endpoint, we empirically demonstrated that a femoral neck T-score of -2.77 for Chinese women was equivalent to -2.60 for Italian women, a spine T-score of -3.75 for Chinese women was equivalent to -2.44 for Italian women, and for Chinese men a femoral neck T-score of -2.77 corresponded to spine T-score of -3.37. For older Chinese men, we tentatively recommend the cutpoint values for T-score of femoral neck, total hip, and spine to be approximately -2.7, -2.6, and -3.2. With the BMD reference published by IKi et al. applied, T-score of femoral neck, total hip, and spine of -2.75, -3.0, and -3.9 for Japanese women will be more in line with the WHO osteoporosis definition. The revised definition of osteoporosis cutpoint T-scores for East Asians will allow a more meaningful international comparison of disease burden.


Asunto(s)
Osteoporosis , Fracturas Osteoporóticas , Masculino , Femenino , Humanos , Anciano , Densidad Ósea , Pueblos del Este de Asia , Osteoporosis/diagnóstico por imagen , Fracturas Osteoporóticas/diagnóstico por imagen , Fracturas Osteoporóticas/epidemiología , Organización Mundial de la Salud , Absorciometría de Fotón
3.
Radiology ; 295(1): 210-217, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32027573

RESUMEN

BackgroundThe chest CT findings of patients with 2019 Novel Coronavirus (2019-nCoV) pneumonia have not previously been described in detail.PurposeTo investigate the clinical, laboratory, and imaging findings of emerging 2019-nCoV pneumonia in humans.Materials and MethodsFifty-one patients (25 men and 26 women; age range 16-76 years) with laboratory-confirmed 2019-nCoV infection by using real-time reverse transcription polymerase chain reaction underwent thin-section CT. The imaging findings, clinical data, and laboratory data were evaluated.ResultsFifty of 51 patients (98%) had a history of contact with individuals from the endemic center in Wuhan, China. Fever (49 of 51, 96%) and cough (24 of 51, 47%) were the most common symptoms. Most patients had a normal white blood cell count (37 of 51, 73%), neutrophil count (44 of 51, 86%), and either normal (17 of 51, 35%) or reduced (33 of 51, 65%) lymphocyte count. CT images showed pure ground-glass opacity (GGO) in 39 of 51 (77%) patients and GGO with reticular and/or interlobular septal thickening in 38 of 51 (75%) patients. GGO with consolidation was present in 30 of 51 (59%) patients, and pure consolidation was present in 28 of 51 (55%) patients. Forty-four of 51 (86%) patients had bilateral lung involvement, while 41 of 51 (80%) involved the posterior part of the lungs and 44 of 51 (86%) were peripheral. There were more consolidated lung lesions in patients 5 days or more from disease onset to CT scan versus 4 days or fewer (431 of 712 lesions vs 129 of 612 lesions; P < .001). Patients older than 50 years had more consolidated lung lesions than did those aged 50 years or younger (212 of 470 vs 198 of 854; P < .001). Follow-up CT in 13 patients showed improvement in seven (54%) patients and progression in four (31%) patients.ConclusionPatients with fever and/or cough and with conspicuous ground-glass opacity lesions in the peripheral and posterior lungs on CT images, combined with normal or decreased white blood cells and a history of epidemic exposure, are highly suspected of having 2019 Novel Coronavirus (2019-nCoV) pneumonia.© RSNA, 2020.


Asunto(s)
Betacoronavirus/aislamiento & purificación , Infecciones por Coronavirus/diagnóstico por imagen , Pulmón/diagnóstico por imagen , Neumonía Viral/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Adolescente , Adulto , Factores de Edad , COVID-19 , Prueba de COVID-19 , China/epidemiología , Técnicas de Laboratorio Clínico , Infecciones por Coronavirus/complicaciones , Infecciones por Coronavirus/diagnóstico , Infecciones por Coronavirus/patología , Tos/etiología , Femenino , Fiebre/etiología , Humanos , Recuento de Leucocitos , Pulmón/patología , Masculino , Persona de Mediana Edad , Neumonía Viral/complicaciones , Neumonía Viral/patología , Reacción en Cadena en Tiempo Real de la Polimerasa , Estudios Retrospectivos , SARS-CoV-2 , Adulto Joven
5.
Scand J Gastroenterol ; 53(9): 1097-1099, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30270701

RESUMEN

BACKGROUND: The value and necessity of pelvic computed tomography (CT) examination in gastric cancer (GC) staging is unknown and the recommendations are unclear in guidelines. The objective of this study was to evaluate the value and necessity of pelvic CT in routine GC staging. METHODS: We reviewed the medical records of GC patients proved by endoscopic biopsy who received abdominopelvic CT examination before treatments at our institution from January 2013 through July 2017. The pathology findings seen in the pelvis were classified into two categories as metastatic disease or not. These findings were further categorized as isolated pelvis metastasis or not, and isolated pelvis metastasis was defined as the presence of pelvis metastasis without any other sites of metastasis on CT scan. RESULTS: A total of 227 GC patients received abdominopelvic CT examinations at our institution. Of the patients, 22.0% (n = 50) had findings in the pelvis, and the most common was ascites (8.8%, n = 20). The metastatic diseases in pelvis were found in 2.2% (n = 5) of all patients, including peritoneal thickening with nodules, left adnexal solid masses, bladder wall mass, bone lesions, and lymphatic spread. The isolated pelvis metastasis was found in 1.3% (n = 3) of patients. CONCLUSIONS: Our results indicated that CT of the pelvis has a negligible yield in GC staging. In consideration of health care cost, radiation dose and radiologist fatigue, the pelvic CT performed as a routine staging tool for GC is unnecessary and not a wise choice in our setting.


Asunto(s)
Metástasis de la Neoplasia/diagnóstico por imagen , Pelvis/diagnóstico por imagen , Neoplasias Gástricas/diagnóstico por imagen , Neoplasias Gástricas/patología , Tomografía Computarizada por Rayos X , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Estudios Retrospectivos
8.
Ann Rheum Dis ; 73(5): 883-9, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-23576710

RESUMEN

BACKGROUND AND OBJECTIVE: Serum leptin measures are associated with radiographic knee osteoarthritis, but no studies have examined leptin levels with respect to different measures of knee joint damage from MRI. METHODS: Participants in the Michigan Study of Women's Health Across the Nation underwent bilateral knee MRIs at follow-up visit 11 for assessment of cartilage defects, bone marrow lesions, osteophytes, meniscal tears, synovitis and joint effusion. Serum leptin measures were available from baseline, follow-up visits 1 and 3-7. RESULTS: Baseline serum leptin levels were associated with greater odds of having more severe knee joint damage at follow-up visit 11 after adjustment for age, smoking status, menopause status and body mass index residuals. The greatest effect was observed for osteophytes; a 5 ng/ml increase in baseline leptin was associated with 24% higher odds of having larger osteophytes (95% CI 1.17 to 1.32). Correlations with baseline serum leptin were greatest for MRI-assessed osteophytes (r=0.41), followed by effusion (r=0.32), synovitis (r=0.30), cartilage defects (r=0.28), bone marrow lesions (r=0.24) and meniscal abnormalities (r=0.21). CONCLUSIONS: Leptin levels 10 years prior to MRI assessment were associated with the presence of cartilage defects, bone marrow lesions, osteophytes, meniscal tears, synovitis and effusion among a population of middle-aged women. Understanding the role that leptin plays in the joint degradation process is critical for development of more targeted interventions for osteoarthritis.


Asunto(s)
Articulación de la Rodilla/patología , Leptina/sangre , Adulto , Femenino , Humanos , Imagen por Resonancia Magnética , Persona de Mediana Edad , Osteoartritis/sangre , Osteoartritis/epidemiología , Osteoartritis/patología , Prevalencia
9.
Radiology ; 268(3): 882-9, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23821754

RESUMEN

PURPOSE: To determine the radiologic findings of human infection with a novel reassortant avian-origin influenza A H7N9 virus in March 2013, the first outbreak in humans. MATERIALS AND METHODS: The institutional review board approved this retrospective study. Twelve patients (nine men and three women) with novel avian-origin influenza A H7N9 virus infection were enrolled. All patients underwent chest radiography and thin-section computed tomography (CT). Lesion patterns, distributions, and changes at follow-up CT were investigated. Two chest radiologists reviewed the images and clinical data together and reached decisions concerning findings by consensus. RESULTS: At presentation, all patients had progressing infection of the lower respiratory tract, with fever, cough, and shortness of breath, which rapidly progressed to acute respiratory distress syndrome. The imaging findings included ground-glass opacities (GGOs) (in 12 of 12 patients), consolidations (in 11 patients), air bronchograms (in 11 patients), interlobular septal thickening (in 11 patients), centrilobular nodules (in seven patients), reticulations (in seven patients), cystic changes (in four patients), bronchial dilatation (in three patients), and subpleural linear opacities (in three patients). The lung lesions involved three or more lobes in all cases and were mostly detected in the right lower lobe (in 11 patients). Follow-up CT in 10 patients showed interval improvement (in three patients) or worsening (in seven patients) of the lesions. Imaging findings closely mirrored the overall clinical severity of the disease. CONCLUSION: Rapidly progressive GGOs and consolidations with air bronchograms and interlobular septal thickening, with right lower lobe predominance, are the main imaging findings in H7N9 pneumonia. The severity of these findings is associated with the severity of the clinical presentation.


Asunto(s)
Enfermedades Transmisibles Emergentes/diagnóstico por imagen , Virus de la Influenza A , Gripe Humana/diagnóstico por imagen , Gripe Humana/microbiología , Neumonía Viral/diagnóstico por imagen , Neumonía Viral/microbiología , Tomografía Computarizada por Rayos X/métodos , Anciano , Anciano de 80 o más Años , Enfermedades Transmisibles Emergentes/microbiología , Femenino , Humanos , Pulmón/diagnóstico por imagen , Pulmón/microbiología , Masculino , Persona de Mediana Edad
10.
J Ultrasound Med ; 32(12): 2075-81, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24277888

RESUMEN

OBJECTIVES: Distinction between musculotendinous tears of the pectoralis major and distal tendon avulsions is important, as the latter typically requires surgical repair. The objective of this study was to characterize the sonographic appearances of surgically proven distal tendon avulsion tears of the pectoralis major. METHODS: A retrospective search of the radiology database (2001-2011) revealed 22 cases of pectoralis major tears on sonography, of which 9 had surgical correlation. Sonograms were retrospectively characterized by 3 fellowship-trained musculoskeletal radiologists in consensus with respect to the location and size of the fluid collection and the presence of tendon or tendonlike tissue superficial to the biceps brachii tendon. RESULTS: At surgery, complete distal tendon avulsions or tears of the sternal head of the pectoralis were present in all 9 cases: isolated in 6 and combined with clavicular head tears in 3. The location of the fluid collection was at the musculotendinous junction in 89% (8 of 9) and medial to the biceps brachii tendon in 11% (1 of 9), with a mean largest dimension of 3.8 cm (range, 0.7-6.2 cm). In no case was fluid seen at the humeral attachment of the pectoralis. In 67% (6 of 9), linear thickened hypoechoic tissue was seen superficial to the biceps brachii tendon, which simulated an abnormal but intact tendon, whereas in 33% (3 of 9), a normal distal pectoralis tendon was seen. CONCLUSIONS: Surgically proven distal pectoralis major tendon avulsions most commonly showed fluid collections at the musculotendinous junction and not at the humeral shaft, with either a normal tendon or hypoechoic tendonlike tissue over the biceps brachii long-head tendon. These findings may potentially cause misdiagnosis of distal tendon avulsions or tears as musculotendinous injuries.


Asunto(s)
Errores Diagnósticos/prevención & control , Laceraciones/diagnóstico por imagen , Músculos Pectorales/diagnóstico por imagen , Músculos Pectorales/lesiones , Traumatismos Torácicos/diagnóstico por imagen , Ultrasonografía/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Rotura/diagnóstico por imagen , Sensibilidad y Especificidad , Adulto Joven
11.
Skeletal Radiol ; 42(9): 1191-200, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23685674

RESUMEN

Lateral ankle pain is common with overuse and sports-related injuries and may cause considerable morbidity. The differential diagnosis of lateral ankle pain is extensive. Disorders of the peroneal tendons should be an important consideration during interpretation of a routine ankle magnetic resonance imaging (MRI) or ultrasound (US). This article presents a review of the common causes of peroneal tendon pathology with particular reference to anatomy, US, and MRI features. The importance of dynamic evaluation with ultrasound is also emphasized.


Asunto(s)
Articulación del Tobillo/diagnóstico por imagen , Articulación del Tobillo/patología , Imagen por Resonancia Magnética/métodos , Tendinopatía/diagnóstico , Traumatismos de los Tendones/diagnóstico , Ultrasonografía/métodos , Humanos
12.
J Transl Med ; 10: 101, 2012 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-22613625

RESUMEN

BACKGROUND: Oncolytic adenoviruses are promising as anticancer agents but have limited clinical responses. Our previous study showed that heat shock transcription factor 1 (HSF1) overexpression could increase the anti-tumor efficacy of E1B55kD deleted oncolytic adenovirus through increasing the viral burst. Due to the important roles of heat shock proteins (HSPs) in eliciting innate and adaptive immunity, we reasoned that besides increasing the viral burst, HSF1 may also play a role in increasing tumor specific immune response. METHODS: In the present study, intra-dermal murine models of melanoma (B16) and colorectal carcinoma (CT26) were treated with E1B55kD deleted oncolytic adenovirus Adel55 or Adel55 incorporated with cHSF1, HSF1i, HSP70, or HSP90 by intra-tumoral injection. Tumors were surgically excised 72 h post injection and animals were analyzed for tumor resistance and survival rate. RESULTS: Approximately 95% of animals in the Adel55-cHSF1 treated group showed sustained resistance upon re-challenge with autologous tumor cells, but not in PBS, Adel55, or Adel55-HSF1i treated groups. Only 50-65% animals in the Adel55-HSP70 and Adel55-HSP90 treated group showed tumor resistance. Tumor resistance was associated with development of tumor type specific cellular immune responses. Adel55-cHSF1 treatment also showed higher efficacy in diminishing progression of the secondary tumor focus than Adel55-HSP70 or Adel55-HSP90 treatment. CONCLUSIONS: Besides by increasing its burst in tumor cells, cHSF1 could also augment the potential of E1B55kD deleted oncolytic adenovirus by increasing the tumor-specific immune response, which is beneficial to prevent tumor recurrence. cHSF1 is a better gene for neoadjuvant immunotherapy than other heat shock protein genes.


Asunto(s)
Adenoviridae/fisiología , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/uso terapéutico , Terapia Genética , Neoplasias/inmunología , Neoplasias/terapia , Factores de Transcripción/genética , Factores de Transcripción/uso terapéutico , Replicación Viral/fisiología , Animales , Técnicas de Transferencia de Gen , Células HEK293 , Factores de Transcripción del Choque Térmico , Humanos , Inmunidad , Inmunoterapia , Estimación de Kaplan-Meier , Ratones , Ratones Endogámicos C57BL , Terapia Neoadyuvante , Micrometástasis de Neoplasia , Neoplasias/patología , Bazo/inmunología , Bazo/patología , Linfocitos T Citotóxicos/inmunología , Resultado del Tratamiento
13.
Nat Med ; 8(9): 943-9, 2002 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-12161749

RESUMEN

The hematopoietic-restricted protein Src homology 2-containing inositol-5-phosphatase (SHIP) blunts phosphatidylinositol-3-kinase-initiated signaling by dephosphorylating its major substrate, phosphatidylinositol-3,4,5-trisphosphate. As SHIP(-/-) mice contain increased numbers of osteoclast precursors, that is, macrophages, we examined bones from these animals and found that osteoclast number is increased two-fold. This increased number is due to the prolonged life span of these cells and to hypersensitivity of precursors to macrophage colony-stimulating factor (M-CSF) and receptor activator of nuclear factor-kappa B ligand (RANKL). Similar to pagetic osteoclasts, SHIP(-/-) osteoclasts are enlarged, containing upwards of 100 nuclei, and exhibit enhanced resorptive activity. Moreover, as in Paget disease, serum levels of interleukin-6 are markedly increased in SHIP(-/-) mice. Consistent with accelerated resorptive activity, 3D trabecular volume fraction, trabecular thickness, number and connectivity density of SHIP(-/-) long bones are reduced, resulting in a 22% loss of bone-mineral density and a 49% decrease in fracture energy. Thus, SHIP negatively regulates osteoclast formation and function and the absence of this enzyme results in severe osteoporosis.


Asunto(s)
Osteoclastos/patología , Osteoporosis/patología , Osteoporosis/fisiopatología , Monoéster Fosfórico Hidrolasas/deficiencia , Animales , Apoptosis/genética , Densidad Ósea , Resorción Ósea/genética , Proteínas Portadoras/farmacología , Recuento de Células , Células Cultivadas , Interleucina-6/sangre , Factor Estimulante de Colonias de Macrófagos/farmacología , Macrófagos/efectos de los fármacos , Glicoproteínas de Membrana/farmacología , Ratones , Ratones Mutantes , Osteoclastos/efectos de los fármacos , Osteoclastos/metabolismo , Fosfatidilinositol-3,4,5-Trifosfato 5-Fosfatasas , Monoéster Fosfórico Hidrolasas/genética , Ligando RANK , Receptor Activador del Factor Nuclear kappa-B
14.
Skeletal Radiol ; 40(8): 1073-8, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21207022

RESUMEN

PURPOSE: The novel protein osteopotentia (Opt) has recently been described as an essential regulator of postnatal osteoblast maturation and might possibly be responsible for some of the rarer types of osteogenesis imperfecta. Our aim was the evaluation of micro CT for the qualitative morphological assessment of skeletal abnormalities of Osteopotentia-mutant mice in comparison to radiography and histology. MATERIALS AND METHODS: Four homozygous mice with insertional mutations in the Opt gene and three wild-type controls were examined ex vivo using radiography and micro-CT. Two of the homozygous animals were evaluated histologically (trichrome reagent). For the micro-CT evaluation three-dimensional (3D) surface reconstructions and two-dimensional (2D) multiplanar reformations (MPRs) were applied. RESULTS: The Opt-homozygous mice exhibited severe growth. The radiographic examinations showed osteopenia and fractures with hypertrophic callus formation and pseudarthroses of the forelimbs and ribs. Micro-CT confirmed these findings and was able to demonstrate additional fractures especially at smaller bones such as the metacarpals and phalanges. Additional characterization and superior delineation of cortices and fracture fragments was achieved by 2D MPRs. Histological correlation verified several of these imaging findings. CONCLUSION: Micro-CT is able to screen Opt-mutant mice for osseous pathologies and furthermore characterize these anomalies. The modality seems superior to conventional radiography, but is not able to demonstrate cellular pathology. However, histology is destructive and more time- and material-consuming than micro-CT. Additional information may be gathered by 2D MPRs.


Asunto(s)
Osteogénesis Imperfecta/diagnóstico por imagen , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Microtomografía por Rayos X/métodos , Animales , Modelos Animales de Enfermedad , Femenino , Imagenología Tridimensional , Proteínas de la Membrana/genética , Ratones , Ratones Mutantes , Osteogénesis Imperfecta/genética , Fenotipo
15.
Skeletal Radiol ; 40(1): 117-22, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20652241

RESUMEN

Inflammatory myofibroblastic tumor (IMT) is an unusual tumor composed of differentiated myofibroblastic spindle cells usually accompanied by numerous plasma cells and lymphocytes. IMT was originally described in the lung; occurrence in a long bone is rare. We present two examples of IMT arising in a long bone: one in the humerus and one in the femur. In both cases, imaging shows a poorly delineated osteolytic lesion with cortical bone destruction that aggressively extends into surrounding soft tissue. Histologically, the lesion is dominated by differentiated spindle cells with aprominent collagenous stroma and an inflammatory component including plasma cells and lymphocytes, and with positive immunoreactivity for anaplastic lymphoma kinase. The absence of cytologic atypia helps differentiate this lesion from malignant spindle cell tumors.


Asunto(s)
Neoplasias Óseas/inmunología , Húmero/diagnóstico por imagen , Miofibroblastos/patología , Adolescente , Adulto , Neoplasias Óseas/diagnóstico por imagen , Femenino , Humanos , Inflamación , Imagen por Resonancia Magnética , Masculino , Tomografía Computarizada por Rayos X
16.
AJR Am J Roentgenol ; 194(1): 216-25, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20028926

RESUMEN

OBJECTIVE: The purpose of this article is to describe the pitfalls that may be encountered when performing musculoskeletal sonography. CONCLUSION: Sonography of the musculoskeletal system is a useful diagnostic technique, but awareness and understanding of the pitfalls will minimize errors in diagnosis.


Asunto(s)
Enfermedades Musculoesqueléticas/diagnóstico por imagen , Sistema Musculoesquelético/diagnóstico por imagen , Anisotropía , Humanos , Extremidad Inferior/diagnóstico por imagen , Valores de Referencia , Ultrasonografía , Extremidad Superior/diagnóstico por imagen
17.
J Clin Invest ; 115(9): 2402-11, 2005 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16138191

RESUMEN

Mice heterozygous for targeted disruption of Pthrp exhibit, by 3 months of age, diminished bone volume and skeletal microarchitectural changes indicative of advanced osteoporosis. Impaired bone formation arising from decreased BM precursor cell recruitment and increased apoptotic death of osteoblastic cells was identified as the underlying mechanism for low bone mass. The osteoporotic phenotype was recapitulated in mice with osteoblast-specific targeted disruption of Pthrp, generated using Cre-LoxP technology, and defective bone formation was reaffirmed as the underlying etiology. Daily administration of the 1-34 amino-terminal fragment of parathyroid hormone (PTH 1-34) to Pthrp+/- mice resulted in profound improvement in all parameters of skeletal microarchitecture, surpassing the improvement observed in treated WT littermates. These findings establish a pivotal role for osteoblast-derived PTH-related protein (PTHrP) as a potent endogenous bone anabolic factor that potentiates bone formation by altering osteoblast recruitment and survival and whose level of expression in the bone microenvironment influences the therapeutic efficacy of exogenous PTH 1-34.


Asunto(s)
Huesos , Osteoblastos/metabolismo , Osteogénesis/fisiología , Proteína Relacionada con la Hormona Paratiroidea/metabolismo , Hormona Paratiroidea/metabolismo , Fragmentos de Péptidos/metabolismo , Animales , Apoptosis/fisiología , Densidad Ósea , Enfermedades Óseas Metabólicas/genética , Enfermedades Óseas Metabólicas/patología , Huesos/anatomía & histología , Huesos/citología , Huesos/metabolismo , Marcación de Gen , Masculino , Ratones , Ratones Noqueados , Ratones Transgénicos , Osteoblastos/citología , Osteoporosis/patología , Osteoporosis/fisiopatología , Hormona Paratiroidea/administración & dosificación , Hormona Paratiroidea/genética , Hormona Paratiroidea/uso terapéutico , Proteína Relacionada con la Hormona Paratiroidea/genética , Fragmentos de Péptidos/administración & dosificación , Fragmentos de Péptidos/genética , Fragmentos de Péptidos/uso terapéutico
18.
Radiology ; 248(3): 737-47, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18710973

RESUMEN

In the presence of joint space narrowing, it is important to differentiate inflammatory from degenerative conditions. The presence of osteophytes, bone sclerosis, and subchondral cysts and the absence of inflammatory features such as erosions suggest osteoarthritis. Typical osteoarthritis involves specific joints at a particular patient age. When osteoarthritis involves an atypical joint, occurs at an early age, or has an unusual radiographic appearance, then other causes for cartilage destruction should be considered, such as trauma, crystal deposition, neuropathic joint, and hemophilia. There are several types of arthritis, such as juvenile chronic arthritis and gouty arthritis, that may have a variable appearance compared with that of other common inflammatory arthritides.


Asunto(s)
Artritis/diagnóstico por imagen , Artrografía/métodos , Enfermedades Neurodegenerativas/diagnóstico , Diagnóstico Diferencial , Humanos
19.
Radiology ; 248(2): 378-89, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18641245

RESUMEN

In the presence of joint space narrowing, it is important to differentiate inflammatory from degenerative conditions. Joint inflammation is characterized by bone erosions, osteopenia, soft-tissue swelling, and uniform joint space loss. Inflammation of a single joint should raise concern for infection. Multiple joint inflammation in a proximal distribution in the hands or feet without bone proliferation suggests rheumatoid arthritis. Multiple joint inflammation in a distal distribution in the hands or feet with bone proliferation suggests a seronegative spondyloarthropathy, such as psoriatic arthritis, reactive arthritis, or ankylosing spondylitis.


Asunto(s)
Artritis/diagnóstico por imagen , Algoritmos , Diagnóstico Diferencial , Humanos , Inflamación/diagnóstico por imagen , Osteofito/diagnóstico por imagen , Radiografía
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