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1.
Int J Radiat Oncol Biol Phys ; 119(1): 185-192, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38070714

RESUMO

PURPOSE: An estimated 30% and 40% of patients with breast cancer experience depression and anxiety, respectively. However, distress experienced by patients with breast cancer receiving radiation therapy may vary among patients and vary at different time points. This study sought to describe the changes in levels of depression and anxiety experienced by English- and Spanish-speaking patients throughout a course of radiation therapy for breast cancer, along with the effect of different variables to better understand potential gaps. METHODS AND MATERIALS: Eligibility criteria included English- and Spanish-speaking females, aged 18 or older, undergoing radiation therapy treatment for breast cancer at 2 institutions. Pre- and posttreatment surveys were completed before and after delivery of radiation therapy. Sociodemographic characteristics collected included race, ethnicity, marital status, education level, longest residency location, religion, housing, and food insecurity. The survey ended with the standardized PHQ-4 questionnaire to assess anxiety and depression. Results were analyzed using the analysis of covariance procedure. RESULTS: A total of 160 participants completed pre- and posttreatment surveys, with an initial response rate of 100% (169 patients), though 9 were lost to follow-up. Most of the participants were nonwhite (50%), primarily married (42.5%), and had a high school or associate's level education (46.9%). The total baseline distress mean (BDM) was 2.96 and the final distress mean was 2.78. English-speaking patients comprised 82.5% (n = 132) of the sample and had a BDM of 2.91 with an adjusted change mean decrease of 0.45. Spanish-speaking patients comprised 17.5% (n = 28) of the sample, with a baseline distress mean of 3.21 and an adjusted change mean increase of 1.03 (P = .002). Housing (P = .017) and food insecurity (P = .0002) also showed increasing distress with increased insecurity at baseline. CONCLUSIONS: Patients who speak Spanish, identify as Hispanic, or are experiencing food and housing insecurity are at an increased risk for depression and anxiety, and could benefit from more support during their course of radiation therapy to minimize distress.


Assuntos
Neoplasias da Mama , Feminino , Humanos , Depressão , Hispânico ou Latino , Ansiedade , Inquéritos e Questionários
2.
Community Health Equity Res Policy ; : 2752535X231221394, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38087807

RESUMO

BACKGROUND: In the United States, less than 5% of all adult cancer patients enroll in clinical trials. Few studies explore participation in cancer clinical trials at safety net hospitals, which disproportionately care for minoritized, low-income, uninsured, and underinsured populations. Our study aims to investigate disparities in clinical trial discussions and enrollment among lung cancer patients at Boston Medical Center, the largest safety net hospital in New England. METHODS: We included 1121 patients diagnosed with lung cancer between January 2015 and December 2020. Electronic Medical Records (EMR) were queried, and patients were categorized into three groups: (1) clinical trial discussed and the patient enrolled, (2) clinical trial discussed but the patient not enrolled, and (3) clinical trial not discussed. Sociodemographic variables such as age, gender, race, ethnicity, city, primary language, median household income, medical insurance type, and education level were also collected. Chi-squared,t test, and multivariate regression analysis was done using SPSS version 26.0. RESULTS: Of the 1121 patients, clinical trials were discussed in 141 patients (12.6%), of which 22 (15.6%) were enrolled. Clinical trial discussions were conducted more with younger patients (68.19 vs 71.37, p = .001), but on multivariate analysis there was no significant difference (OR = 1.023; 95% CI 0.998-1.048; p = .068). There was no significant difference in clinical trial discussion or enrollment between the other sociodemographic factors. CONCLUSION: Additional study of barriers to cancer clinical trial discussion and enrollment at safety net institutions can serve as a prerequisite to ameliorating racial disparities observed on a national scale.

3.
Artigo em Inglês | MEDLINE | ID: mdl-37651069

RESUMO

BACKGROUND: Disparities within clinical trial enrollment are well-documented, reducing the generalizability of results. Although nearly 30 years have passed since Congress passed the NIH Revitalization Act to encourage the participation of minoritized populations in clinical trials, these patients continue to be underrepresented. This study aimed to investigate lung cancer clinical trial enrollment disparities for race/ethnicity, sex, and age. METHODS: We queried the National Institutes of Health: US National Library of Medicine database of clinical trials for all US-based lung cancer clinical trials completed between 2004 and 2021 and collected data on race and ethnicity, gender, and age breakdown. This data was compared to Surveillance, Epidemiology, and End Results (SEER) database data. Independent sample t-tests and Kruskal-Wallis's approach were used to analyze the data. RESULTS: Of 311 eligible trials with exclusive US enrollment, 136 (44%) reported race and ethnicity breakdown for the patient cohort representing 9869 patients. Hispanic, Non-Hispanic American Indian/Alaska Native, Non-Hispanic Black, and Non-Hispanic Unreported participants were underrepresented (p = 0.001, p = 0.005, p = 0.014, p = 0.002, respectively). Non-Hispanic White participants were overrepresented (p = 0.018). Disparities worsened from 2017 to 2021 for Hispanic patients (p = 0.03). No significant differences were found for sex or age. CONCLUSIONS: Disparities for clinical lung cancer trial enrollment have not shown statistically significant improvement since 2004, and representation remains unequal, especially for racial and ethnic minorities.

4.
Clin Lung Cancer ; 24(2): e87-e93, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36642641

RESUMO

BACKGROUND: Timeliness of care is an important metric for lung cancer patients, and care delays in the safety-net setting have been described. Timeliness from the point of the suspicious image is not well-studied. Herein, we evaluate time intervals in the workup of lung cancer at an urban, safety net hospital and assess for disparities by demographic and clinical factors. PATIENTS AND METHODS: We performed a retrospective analysis of lung cancer patients receiving some portion of their care at Boston Medical Center between 2015 and 2020. A total of 687 patients were included in the final analysis. Median times from suspicious image to first treatment (SIT), suspicious image to diagnosis (SID), and diagnosis to treatment (DT) were calculated. Nonparametric tests were applied to assess for intergroup differences in time intervals. RESULTS: SIT, SID, and DT for the entire cohort was 78, 34, and 32 days, respectively. SIT intervals were 87 days for females and 72 days for males (p < .01). SIT intervals were 106, 110, 81, and 41 days for stages I, II, III, and IV, respectively (p < .01). SID intervals differed between black (40.5) and Hispanic (45) patients compared to white (28) and Asian (23) patients (p < .05). CONCLUSION: Advanced stage at presentation and male gender were associated with more timely treatment from the point of suspicious imaging while white and Asian were associated with more timely lung cancer diagnosis. Future analyses should seek to elucidate drivers of timeliness differences and assess for the impact of timeliness disparities on patient outcomes in the safety net setting.


Assuntos
Disparidades em Assistência à Saúde , Neoplasias Pulmonares , Feminino , Humanos , Masculino , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/terapia , Estudos Retrospectivos , Provedores de Redes de Segurança , Disparidades em Assistência à Saúde/etnologia
5.
Epigenomes ; 4(2)2020 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-34968243

RESUMO

DNA methylation is an important epigenetic mark involved in gene regulation and silencing of transposable elements. The presence or absence of DNA methylation at specific sites can influence nearby gene expression and cause phenotypic changes that remain stable over generations. Recently, development of new technologies has enabled the targeted addition or removal of DNA methylation at specific sites of the genome. Of these new technologies, the targeting of the catalytic domain of Nicotiana tabacum DOMAINS REARRANGED METHYLTRANSFERASE 2 (ntDRM2cd) offers a promising tool for the addition of DNA methylation as it can directly methylate DNA. However, the methylation targeting efficiency of constructs using ntDRM2cd thus far has been relatively low. Previous studies have shown that the use of different promoters or terminators can greatly improve genome-editing efficiencies. In this study, we systematically survey a variety of promoter and terminator combinations to identify optimal combinations to use when targeting the addition of DNA methylation in Arabidopsis thaliana.

6.
Proc Natl Acad Sci U S A ; 115(9): E2125-E2134, 2018 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-29444862

RESUMO

DNA methylation is an important epigenetic modification involved in gene regulation and transposable element silencing. Changes in DNA methylation can be heritable and, thus, can lead to the formation of stable epialleles. A well-characterized example of a stable epiallele in plants is fwa, which consists of the loss of DNA cytosine methylation (5mC) in the promoter of the FLOWERING WAGENINGEN (FWA) gene, causing up-regulation of FWA and a heritable late-flowering phenotype. Here we demonstrate that a fusion between the catalytic domain of the human demethylase TEN-ELEVEN TRANSLOCATION1 (TET1cd) and an artificial zinc finger (ZF) designed to target the FWA promoter can cause highly efficient targeted demethylation, FWA up-regulation, and a heritable late-flowering phenotype. Additional ZF-TET1cd fusions designed to target methylated regions of the CACTA1 transposon also caused targeted demethylation and changes in expression. Finally, we have developed a CRISPR/dCas9-based targeted demethylation system using the TET1cd and a modified SunTag system. Similar to the ZF-TET1cd fusions, the SunTag-TET1cd system is able to target demethylation and activate gene expression when directed to the FWA or CACTA1 loci. Our study provides tools for targeted removal of 5mC at specific loci in the genome with high specificity and minimal off-target effects. These tools provide the opportunity to develop new epialleles for traits of interest, and to reactivate expression of previously silenced genes, transgenes, or transposons.


Assuntos
Arabidopsis/genética , Metilação de DNA , Genoma de Planta , Oxigenases de Função Mista/química , Proteínas Proto-Oncogênicas/química , Proteínas de Arabidopsis/metabolismo , Domínio Catalítico , Elementos de DNA Transponíveis , DNA de Plantas/química , Epigênese Genética , Flores , Regulação da Expressão Gênica de Plantas , Inativação Gênica , Proteínas de Homeodomínio/metabolismo , Humanos , Mutação , Regiões Promotoras Genéticas , Fatores de Transcrição/metabolismo , Dedos de Zinco
7.
Food Chem ; 227: 194-201, 2017 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-28274422

RESUMO

Squid pens were subjected to alkali hydrolysis to extract chitin and chitosan. Proteins present in the alkaline extraction wastewater were recovered at pH 3, 4, 5 and 6, and were subjected to hydrolysis by trypsin, pepsin and a bacterial protease called HT for 1, 2, 4 and 24h. Hydrolysis of the extracted proteins with either trypsin or HT generated more antioxidant activity than hydrolysis with pepsin. Higher ACE-inhibitory activity was generated in the trypsin and pepsin hydrolysates than in the HT hydrolysate. Squid pen protein recovered from chitosan processing waste alkaline solution can be a potential source of bioactive peptides for addition to foods. The antioxidant and ACE-inhibitory activities of the extracted proteins were initially low and increased upon incubation with the proteases. Pepsin generated significantly lower (P<0.05) antioxidant activities compared to trypsin and HT, while trypsin and pepsin hydrolysates exhibited higher ACE-inhibitory activity than HT (P<0.05).


Assuntos
Antioxidantes/química , Quitosana/química , Decapodiformes/química , Hidrolisados de Proteína/química , Animais , Quitosana/metabolismo , Hidrólise , Peptídeo Hidrolases/metabolismo
8.
Gastroenterology ; 141(3): 1003-1013.e1-10, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21699772

RESUMO

BACKGROUND & AIMS: Adenomatous polyps are precursors to colorectal cancer (CRC), whereas hyperplastic polyps (HPPs) have low risk of progression to CRC. Mutations in KRAS are found in ∼40% of CRCs and large adenomas and a subset of HPPs. We investigated the reasons why HPPs with KRAS mutations lack malignant potential and compared the effects of Kras/KRAS activation with those of Apc/APC inactivation, which promotes adenoma formation. METHODS: We activated a KrasG12D mutant allele or inactivated Apc alleles in mouse colon epithelium and analyzed phenotypes and expression of selected genes and proteins. The mouse data were validated using samples of human HPPs and adenomas. Signaling pathways and factors contributing to Kras/KRAS-induced phenotypes were studied in intestinal epithelial cells. RESULTS: Activation of Kras led to hyperplasia and serrated crypt architecture akin to that observed in human HPPs. We also observed loss of Paneth cells and increases in goblet cell numbers. Abnormalities in Kras-mediated differentiation and proliferation required mitogen-activated protein kinase signaling and were linked to activation of the Hes1 transcription factor. Human HPPs also had activation of HES1. In contrast to Apc/APC inactivation, Kras/KRAS activation did not increase expression of crypt stem cell markers in colon epithelium or colony formation in vitro. Kras/KRAS activation was not associated with substantial induction of p16(INK4a) protein expression in mouse colon epithelium or human HPPs. CONCLUSIONS: Although Kras/KRAS mutation promotes serrated and hyperplastic morphologic features in colon epithelium, it is not able to initiate adenoma development, perhaps in part because activated Kras/KRAS signaling does not increase the number of presumptive stem cells in affected crypts.


Assuntos
Diferenciação Celular/fisiologia , Colo/patologia , Mucosa Intestinal/patologia , Mutação/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteínas Proto-Oncogênicas p21(ras)/fisiologia , Células-Tronco/patologia , Adenoma/patologia , Adenoma/fisiopatologia , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/fisiologia , Linhagem Celular , Proliferação de Células , Colo/fisiologia , Pólipos do Colo/patologia , Pólipos do Colo/fisiopatologia , Neoplasias Colorretais/patologia , Neoplasias Colorretais/fisiopatologia , Modelos Animais de Doenças , Progressão da Doença , Proteínas de Homeodomínio/fisiologia , Humanos , Hiperplasia , Mucosa Intestinal/fisiologia , Camundongos , Camundongos Transgênicos , Transdução de Sinais/fisiologia , Fatores de Transcrição HES-1
9.
Food Chem ; 129(3): 837-45, 2011 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-25212307

RESUMO

Grape skin extracts from pinot noir and pinot gris exhibited significant in vitro antiviral (influenza virus) activity. Five tea infusions from grape skins (Vitis vinifera var. pinot noir and pinot gris) without any additives (control pinot noir and control pinot gris) or by adding variable amounts of green tea and hibiscus were investigated as a means to utilise wine wastes. The antioxidant activities (DPPH scavenging capacity and superoxide anion radical scavenging capacity), total phenolics, the polyphenolics profile and objective colour measurements (CIELab) were determined on freeze-dried water extracts of all five tea infusions, hibiscus and green tea. The colour parameters, L(∗) and a(∗) values, varied widely (P<0.05) for all the infusions as a result of having different levels and variety of pigments. The tea infusions exhibited weak antioxidant activity and the antiviral activity in grape skin appears not related to phenolics contents.

10.
J Bone Miner Res ; 23(2): 215-22, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17922612

RESUMO

UNLABELLED: Strontium ranelate is a new anti-osteoporotic treatment. On bone biopsies collected from humans receiving long-term treatment over 5 yr, it has been shown that strontium ranelate has good bone safety and better results than placebo on 3D microarchitecture. Hence, these effects may explain the decreased fracture rate. INTRODUCTION: Strontium ranelate's mode of action involving dissociation of bone formation and resorption was shown in preclinical studies and could explain its antifracture efficacy in humans. MATERIALS AND METHODS: One hundred forty-one transiliac bone biopsies were obtained from 133 postmenopausal osteoporotic women: 49 biopsies after 1-5 yr of 2 g/d strontium ranelate and 92 biopsies at baseline or after 1-5 yr of placebo. RESULTS AND CONCLUSIONS: Histomorphometry provided a 2D demonstration of the bone safety of strontium ranelate, with significantly higher mineral apposition rate (MAR) in cancellous bone (+9% versus control, p = 0.019) and borderline higher in cortical bone (+10%, p = 0.056). Osteoblast surfaces were significantly higher (+38% versus control, p = 0.047). 3D analysis of 3-yr biopsies with treatment (20 biopsies) and placebo (21 biopsies) using microCT showed significant changes in microarchitecture with, in the strontium ranelate group, higher cortical thickness (+18%, p = 0.008) and trabecular number (+14%, p = 0.05), and lower structure model index (-22%, p = 0.01) and trabecular separation (-16%, p = 0.04), with no change in cortical porosity. The changes in 3D microarchitecture may enhance bone biomechanical competence and explain the decreased fracture rate with strontium ranelate.


Assuntos
Ílio/efeitos dos fármacos , Compostos Organometálicos/uso terapêutico , Osteoporose Pós-Menopausa/tratamento farmacológico , Tiofenos/uso terapêutico , Idoso , Biópsia , Remodelação Óssea/efeitos dos fármacos , Método Duplo-Cego , Feminino , Histocitoquímica , Humanos , Ílio/patologia , Pessoa de Meia-Idade , Compostos Organometálicos/efeitos adversos , Osteoblastos/efeitos dos fármacos , Osteoblastos/patologia , Osteogênese/efeitos dos fármacos , Osteoporose Pós-Menopausa/diagnóstico por imagem , Pós-Menopausa , Tiofenos/efeitos adversos , Tempo , Tomografia Computadorizada por Raios X/instrumentação , Tomografia Computadorizada por Raios X/métodos
11.
J Pharmacol Exp Ther ; 318(1): 132-41, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16597712

RESUMO

Destruction of cartilage and bone is a poorly managed hallmark of human rheumatoid arthritis (RA). p38 Mitogen-activated protein kinase (MAPK) has been shown to regulate key proinflammatory pathways in RA, including tumor necrosis factor alpha, interleukin (IL)-1beta, and cyclooxygenase-2, as well as the process of osteoclast differentiation. Therefore, we evaluated whether a p38alpha MAPK inhibitor, indole-5-carboxamide (SD-282), could modulate cartilage and bone destruction in a mouse model of RA induced with bovine type II collagen [collagen-induced arthritis (CIA)]. In mice with early disease, SD-282 treatment significantly improved clinical severity scores, reduced bone and cartilage loss, and reduced mRNA levels of proinflammatory genes in paw tissue, including IL-1beta, IL-6, and cyclooxygenase-2. Notably, SD-282 treatment of mice with advanced disease resulted in significant improvement in clinical severity scoring and paw swelling, a reversal in bone and cartilage destruction as assessed by histology, bone volume fraction and thickness, and three-dimensional image analysis. These changes were accompanied by reduced osteoclast number and lowered levels of serum cartilage oligomeric matrix protein, a marker of cartilage breakdown. Thus, in a model of experimental arthritis associated with significant osteolysis, p38alpha MAPK inhibition not only attenuates disease progression but also reverses cartilage and bone destruction in mice with advanced CIA disease.


Assuntos
Antirreumáticos/uso terapêutico , Artrite Experimental/enzimologia , Doenças das Cartilagens/enzimologia , Ossos do Pé/enzimologia , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores , Animais , Antirreumáticos/farmacologia , Artrite Experimental/tratamento farmacológico , Artrite Experimental/patologia , Doenças das Cartilagens/tratamento farmacológico , Doenças das Cartilagens/patologia , Ossos do Pé/efeitos dos fármacos , Ossos do Pé/patologia , Masculino , Camundongos , Camundongos Endogâmicos DBA , Osteoclastos/efeitos dos fármacos , Osteoclastos/enzimologia , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
12.
J Clin Invest ; 115(9): 2402-11, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16138191

RESUMO

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.


Assuntos
Osso e Ossos , Osteoblastos/metabolismo , Osteogênese/fisiologia , Proteína Relacionada ao Hormônio Paratireóideo/metabolismo , Hormônio Paratireóideo/metabolismo , Fragmentos de Peptídeos/metabolismo , Animais , Apoptose/fisiologia , Densidade Óssea , Doenças Ósseas Metabólicas/genética , Doenças Ósseas Metabólicas/patologia , Osso e Ossos/anatomia & histologia , Osso e Ossos/citologia , Osso e Ossos/metabolismo , Marcação de Genes , Masculino , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Osteoblastos/citologia , Osteoporose/patologia , Osteoporose/fisiopatologia , Hormônio Paratireóideo/administração & dosagem , Hormônio Paratireóideo/genética , Hormônio Paratireóideo/uso terapêutico , Proteína Relacionada ao Hormônio Paratireóideo/genética , Fragmentos de Peptídeos/administração & dosagem , Fragmentos de Peptídeos/genética , Fragmentos de Peptídeos/uso terapêutico
13.
J Bone Miner Metab ; 23 Suppl: 122-31, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15984427

RESUMO

As the mechanical competence of trabecular bone is a function of its apparent density and 3-D distribution, assessment of 3-D trabecular structural characteristics may improve our ability to understand the pathophysiology of osteoporosis, to test the efficacy of pharmaceutical intervention, and to estimate bone biomechanical properties. We have studied ovariectomy-induced osteopenia in rats and its treatment with agents such as estrogen and sodium fluoride. We have demonstrated that 3-D micro-computed tomography (microCT) can directly quantify mouse trabecular and cortical bone structure with an isotropic resolution of 6 microm(3). MicroCT is also useful for studying osteoporosis in mice and phenotypes of mice with gene manipulation, such as SHIP-knockout mice, which are severely osteoporotic due to increased numbers of hyperresorptive osteoclasts, PTHrP heterozygous-null mice, and mice with Zmpste24 deficiency. MicroCT can quantify osteogenesis in mouse Ilizarov leg-lengthening procedures, osteoconduction in a rat cranial defect model, and structural changes in arthritic rabbits, rats, and mice. In clinical studies, we evaluated longitudinal changes in the iliac crests. Paired bone biopsies from the same premenopausal and postmenopausal women showed the changes in 3-D trabecular structure, such as decreased trabecular thickness, shifting of trabecular model from platelike structure to rodlike structure, and decreased degree of anisotropy were remarkable. Treatment with PTH in postmenopausal women with osteoporosis significantly improved trabecular morphology with a shift toward a more platelike structure, increased trabecular connectivity density, and increased cortical thickness. Paired bone biopsy specimens from the iliac crest in postmenopausal women with osteoporosis before and an average of 2 years after beginning of estrogen replacement therapy demonstrated that posttreatment biopsies showed a significant change in the ratio of plates to rods and statistically insignificant changes in other 3-D trabecular parameters. Thus, microCT can characterize 3-D structure of various animal models, and the longitudinal changes in 3-D bone microarchitectural integrity that deteriorates in the transmenopausal period, is preserved with HRT, and is improved with PTH treatment in postmenopausal women.


Assuntos
Densidade Óssea , Osso e Ossos/diagnóstico por imagem , Imageamento Tridimensional , Microrradiografia , Osteoporose Pós-Menopausa/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Animais , Feminino , Humanos , Masculino , Camundongos , Camundongos Knockout , Osteoporose Pós-Menopausa/patologia , Ratos
14.
J Bone Miner Res ; 18(11): 1932-41, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14606504

RESUMO

UNLABELLED: Histomorphometry and microCT of 51 paired iliac crest biopsy specimens from women treated with teriparatide revealed significant increases in cancellous bone volume, cancellous bone connectivity density, cancellous bone plate-like structure, and cortical thickness, and a reduction in marrow star volume. INTRODUCTION: We studied the ability of teriparatide (rDNA origin) injection [rhPTH(1-34), TPTD] to improve both cancellous and cortical bone in a subset of women enrolled in the Fracture Prevention Trial of postmenopausal women with osteoporosis after a mean treatment time of 19 months. This is the first report of a biopsy study after treatment with teriparatide having a sufficient number of paired biopsy samples to provide quantitative structural data. METHODS: Fifty-one paired iliac crest bone biopsy specimens (placebo [n = 19], 20 microg teriparatide [n = 18], and 40 microg teriparatide [n = 14]) were analyzed using both two-dimensional (2D) histomorphometry and three-dimensional (3D) microcomputed tomography (microCT). Data for both teriparatide treatment groups were pooled for analysis. RESULTS AND CONCLUSIONS: By 2D histomorphometric analyses, teriparatide significantly increased cancellous bone volume (median percent change: teriparatide, 14%; placebo, -24%; p = 0.001) and reduced marrow star volume (teriparatide, -16%; placebo, 112%; p = 0.004). Teriparatide administration was not associated with osteomalacia or woven bone, and there were no significant changes in mineral appositional rate or wall thickness. By 3D cancellous and cortical bone structural analyses, teriparatide significantly decreased the cancellous structure model index (teriparatide, -12%; placebo, 7%; p = 0.025), increased cancellous connectivity density (teriparatide, 19%; placebo, - 14%; p = 0.034), and increased cortical thickness (teriparatide, 22%; placebo, 3%; p = 0.012). These data show that teriparatide treatment of postmenopausal women with osteoporosis significantly increased cancellous bone volume and connectivity, improved trabecular morphology with a shift toward a more plate-like structure, and increased cortical bone thickness. These changes in cancellous and cortical bone morphology should improve biomechanical competence and are consistent with the substantially reduced incidences of vertebral and nonvertebral fractures during administration of teriparatide.


Assuntos
Densidade Óssea/efeitos dos fármacos , Osso e Ossos/efeitos dos fármacos , Teriparatida/farmacologia , Idoso , Biópsia , Osso e Ossos/metabolismo , Método Duplo-Cego , Feminino , Colo do Fêmur/efeitos dos fármacos , Colo do Fêmur/metabolismo , Humanos , Vértebras Lombares/efeitos dos fármacos , Vértebras Lombares/metabolismo , Masculino , Pessoa de Meia-Idade , Pós-Menopausa/fisiologia
15.
Skeletal Radiol ; 31(9): 522-8, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12195505

RESUMO

OBJECTIVE: When planning surgery in patients with rotator cuff tear, strength of bone at the tendon insertion and trabecular bone structure in the greater tuberosity are usually taken into consideration. We investigated radiographic changes in bone structure of the greater tuberosity in rotator cuff tears. DESIGN: Twenty-two human cadaveric shoulders from subjects ranging from 55 to 75 years of age were obtained. The integrity of the rotator cuff was examined by sonography to determine if it is intact without any tear, or torn partially or completely. The humeral head was sectioned in 3 mm thick coronal slab sections and microradiographed. After digitization of the microradiographs and imaging processing with in-house semi-automated image processing software tools developed using software interfaces on a Sun workstation, the trabecular histomorphometrical structural parameters and connectivity in the greater tuberosity were quantified. The degenerative changes on the surface of the greater tuberosity were interpreted blindly by 2 independent readers. RESULTS: Among the 22 shoulder specimens, the rotator cuff was found intact in 10 shoulders, partially in 7 and fully torn in 5. Statistically significant loss in apparent trabecular bone volume fraction, number of trabecular nodes, and number of trabecular branches, and a statistically significant increase in apparent trabecular separation and number of trabecular free ends were found in the greater tuberosity of the shoulders with tears. The loss was greater in association with full tear than in partial tear. Thickening of the cortical margin of the enthesis, irregularity of its surface, and calcification beyond the tidemark were observed in 2 (20%) shoulders with intact rotator cuff, in 6 (86%) shoulders with partial tear, and in 5 (100%) shoulders with full tear. CONCLUSIONS: Rotator cuff tears are associated with degenerative changes on the bone surface and with disuse osteopenia of the greater tuberosity. Aging, degenerative enthesopathy of the supraspinatus tendon, and rotator cuff tears appear closely related.


Assuntos
Úmero/patologia , Manguito Rotador/patologia , Idoso , Cadáver , Humanos , Úmero/diagnóstico por imagem , Processamento de Imagem Assistida por Computador , Pessoa de Meia-Idade , Radiografia , Manguito Rotador/diagnóstico por imagem , Estatísticas não Paramétricas , Ultrassonografia
16.
Nat Med ; 8(9): 943-9, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12161749

RESUMO

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.


Assuntos
Osteoclastos/patologia , Osteoporose/patologia , Osteoporose/fisiopatologia , Monoéster Fosfórico Hidrolases/deficiência , Animais , Apoptose/genética , Densidade Óssea , Reabsorção Óssea/genética , Proteínas de Transporte/farmacologia , Contagem de Células , Células Cultivadas , Interleucina-6/sangue , Fator Estimulador de Colônias de Macrófagos/farmacologia , Macrófagos/efeitos dos fármacos , Glicoproteínas de Membrana/farmacologia , Camundongos , Camundongos Mutantes , Osteoclastos/efeitos dos fármacos , Osteoclastos/metabolismo , Fosfatidilinositol-3,4,5-Trifosfato 5-Fosfatases , Monoéster Fosfórico Hidrolases/genética , Ligante RANK , Receptor Ativador de Fator Nuclear kappa-B
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