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1.
Ann Hum Biol ; 49(7-8): 317-322, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36218419

RESUMO

BACKGROUND: Diabetes comprises a serious disease with significant growth in the number of cases in recent years. Here, we cover the gap in information between leptin (LEP) and type 1 diabetes in the Iranian population. AIM: To recognise LEP G2548A and LEP receptor Q223R polymorphisms in Iranian people and their association with type 1 diabetes susceptibility. SUBJECTS AND METHODS: Characteristics such as fasting blood sugar (FBS) were measured in 80 control non-diabetic individuals and 89 diabetic patients. Moreover, LEP G2548A and LEP receptor Q223R polymorphisms were genotyped using polymerase chain reaction-restriction fragment length polymorphism technique. RESULTS: The frequency of the A allele was nearly three times greater in diabetes patients than in the control group. In addition, in the diabetes group, the AA genotype was five times greater than in the control group (p < 0.01). Furthermore, AA and AA + AG genotype models had higher FBS levels than the GG + AG and GG genotype models, respectively (p < 0.01). CONCLUSION: The LEP G2548A polymorphism could be related to type 1 diabetes susceptibility, but not LEPR Q223R polymorphism in the Iranian population. Importantly, further studies are essential to examine the impact of LEP G2548A and LEPR Q223R polymorphisms in the endocrinology area.


Assuntos
Diabetes Mellitus Tipo 1 , Leptina , Humanos , Leptina/genética , Irã (Geográfico) , Diabetes Mellitus Tipo 1/epidemiologia , Diabetes Mellitus Tipo 1/genética , Polimorfismo de Nucleotídeo Único , Predisposição Genética para Doença , Genótipo , Frequência do Gene
2.
J Surg Oncol ; 113(5): 515-21, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26818116

RESUMO

BACKGROUND AND OBJECTIVES: Surgical interventions can alter the balance between pro- and anti-angiogenic growth factors and thereby modulate tumor growth. Since the microcirculatory properties of tumors underlie organ-specific differences, the microhemodynamic characteristics of bone metastasis have not yet been fully described. Angiogenesis inhibitors are increasingly being used to treat advanced stages of cancer. We hypothesized that the anti-angiogenic drug sunitinib abrogates alterations in microvascular properties following a minor surgical intervention in an in vivo model of secondary breast cancer growth in the bone. METHODS: Intravital microscopy was performed over 25 days using a xenograft model of breast cancer tumor growth in the bone to determine changes in microvascular properties during sunitinib treatment. Mastectomy was performed on day 5 to evaluate the effect of a minor surgical trauma on tumor growth and microvascular properties. RESULTS: Anti-angiogenic therapy resulted in reduced tumor growth, decreased vascular density, and increased vascular diameters. Blood flow velocity remained constant while microvascular permeability temporarily increased after the surgical intervention. CONCLUSIONS: Administration of sunitinib reduced tumor growth and altered microcirculatory properties in a time-dependent manner. The observed dramatic increase in microvascular permeability after the surgical intervention may have implications for local tumor growth, and metastatic dissemination. J. Surg. Oncol. 2016;113:515-521. © 2016 Wiley Periodicals, Inc.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Neoplasias Ósseas/tratamento farmacológico , Neoplasias Ósseas/secundário , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Indóis/uso terapêutico , Pirróis/uso terapêutico , Animais , Neoplasias Ósseas/irrigação sanguínea , Neoplasias da Mama/irrigação sanguínea , Feminino , Camundongos , Camundongos SCID , Microcirculação , Sunitinibe , Ensaios Antitumorais Modelo de Xenoenxerto
3.
Rheumatol Int ; 33(2): 523-7, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22068355

RESUMO

We investigated whether the angiogenic profile, which is based on the local expression and systemic levels of angiogenic growth factors (VEGF, Ang-1, Ang-2, and the corresponding receptors), differs between rheumatoid arthritis (RA) and osteoarthritis (OA) patients. We determined the expression of VEGF, Ang-1, and Ang-2 together with its receptors (VEGFR-1/-2 and Tie2) in synovium tissue (ST) and muscular tissue (MT) from patients with RA and OA using quantitative PCR. Tissue samples were obtained from 15 RA and 19 OA patients during total knee arthroplasty. Control MT samples (n = 10) were obtained during spinal surgery. Results are correlated to VEGF and angiopoietin serum levels via ELISA measurements. The VEGF expressions in ST and serum levels were significantly higher in RA patients than in OA patients (P < 0.05). Furthermore, the VEGFR-1 and VEGFR-2 expression in ST from RA patients were significantly higher than in OA patients (P < 0.001 and P < 0.05). The relative concentration of angiopoietins (Ang-1/Ang-2 ratio) was significantly increased in RA (P < 0.01). Serum levels for Ang-2 showed no significant differences. Statistical analysis showed a significant higher level of Tie2 in RA patients (P < 0.001). Analysis of local levels of VEGF, VEGFR-1, VEGFR-2, Ang-1, Ang-2, and Tie2 in the muscular tissue showed no significant difference between RA and OA patients. These results underline the importance of pro-angiogenic growth factor levels for RA corroborating the assumption that VEGF and angiopoietins play an important role in the pathogenesis of RA.


Assuntos
Proteínas Angiogênicas/análise , Artrite Reumatoide/metabolismo , Adulto , Idoso , Proteínas Angiogênicas/fisiologia , Angiopoietinas/análise , Artrite Reumatoide/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Osteoartrite/metabolismo , Receptor TIE-2/análise , Receptores de Fatores de Crescimento do Endotélio Vascular/análise , Membrana Sinovial/química , Fator A de Crescimento do Endotélio Vascular/análise
4.
Artigo em Inglês | MEDLINE | ID: mdl-30158993

RESUMO

BACKGROUND: The effect of the daily consumption of Morinda citrifolia (Noni) fruit juice on the physiological status of patients with diabetes type 2 (DT2) was tested over a period of two months. METHODS: Morinda citrifolia (Noni) fruit juice (NFJ), 2 ml per kg bw per day, was consumed by twenty patients with DT2 after they underwent a standard treatment regimen including carbohydrate reduced diet and treatment with an antidiabetic drug and/or insulin. NFJ consumption started only after no further improvement was achieved. The intake of NFJ was terminated after eight weeks. The fasting blood sugar level was monitored every morning during the entire treatment period. Blood samples were taken before, at, and four and eight weeks after the start of NFJ intake. The analysis of the blood samples included the concentration of blood glucose, HbA1c, C-peptide, hs-CRP, triglycerides, total cholesterol, LDL, and HDL. RESULTS: The consumption of NFJ by 20 patients with DT2 resulted in a significant mean decrease of the morning blood sugar level monitored over a period of eight weeks. While NFJ reduced the blood glucose level in several but not all hyperglycemic patients, it did not cause hypoglycemia in normoglycemic patients. NFJ consumption also reduced the mean HbA1c value significantly (p= 0.033). Significant decreases (p= 0.01) were also achieved for high sensitive CRP values in patients starting with high levels (>2 mg/L), whereas no change was observed in patients with normal values (< 2 mg/L). The level of C-peptide showed a significant mean increase after four weeks of NFJ consumption in those patients who started with low levels (<3 µg/l, p=0.004, N=11) but not in patients with higher levels (> 3 µg/L). CONCLUSION: The daily consumption of NFJ has the potential to regulate elevated blood sugar levels and some other pathological parameters in patients with DT2. NFJ therefore serves as a suitable additive to the diet of diabetic patients.

5.
Spine (Phila Pa 1976) ; 42(10): 789-797, 2017 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-27584676

RESUMO

STUDY DESIGN: Prospective propensity score-matched study. OBJECTIVE: To compare the outcomes of minimal invasive surgery (MIS) and conventional open surgery for spinal metastasis patients. SUMMARY OF BACKGROUND DATA: There is lack of knowledge on whether MIS is comparable to conventional open surgery in treating spinal metastasis. METHODS: Patients with spinal metastasis requiring surgery from January 2008 to December 2010 in two spine centers were recruited. The demographic, preoperative, operative, perioperative and postoperative data were collected and analyzed. Thirty MIS patients were matched with 30 open surgery patients using propensity score matching technique with a match tolerance of 0.02 based on the covariate age, tumor type, Tokuhashi score, and Tomita score. RESULTS: Both groups had significant improvements in Eastern Cooperative Oncology Group (ECOG), Karnofsky scores, visual analogue scale (VAS) for pain and neurological status postoperatively. However, the difference comparing the MIS and open surgery group was not statistically significant. MIS group had significantly longer instrumented segments (5.5 ±â€Š3.1) compared with open group (3.8 ±â€Š1.7). Open group had significantly longer decompressed segment (1.8 ±â€Š0.8) than MIS group (1.0 ±â€Š1.0). Open group had significantly more blood loss (2062.1 ±â€Š1148.0 mL) compared with MIS group (1156.0 ±â€Š572.3 mL). More patients in the open group (76.7%) needed blood transfusions (with higher average units of blood transfused) compared with MIS group (40.0%). Fluoroscopy time was significantly longer in MIS group (116.1 ±â€Š63.3 s) compared with open group (69.9 ±â€Š42.6 s). Open group required longer hospitalization (21.1 ±â€Š10.8 days) compared with MIS group (11.0 ±â€Š5.0 days). CONCLUSION: This study demonstrated that MIS resulted in comparable outcome to open surgery for patients with spinal metastasis but has the advantage of less blood loss, blood transfusions, and shorter hospital stay. LEVEL OF EVIDENCE: 3.


Assuntos
Descompressão Cirúrgica , Tempo de Internação/estatística & dados numéricos , Procedimentos Cirúrgicos Minimamente Invasivos , Procedimentos Neurocirúrgicos , Neoplasias da Coluna Vertebral/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Descompressão Cirúrgica/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Procedimentos Neurocirúrgicos/métodos , Medição da Dor , Hemorragia Pós-Operatória/patologia , Estudos Prospectivos , Neoplasias da Coluna Vertebral/secundário , Resultado do Tratamento
6.
Diabetes ; 52(2): 542-9, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12540633

RESUMO

Vascular alterations are the most common causes of morbidity and mortality in diabetic patients. Despite the impact of endothelial dysfunction on microcirculatory properties, little is known about the endothelial cell alteration during the development of diabetes and its correlation to the metabolic situation. For that reason we continuously monitored in vivo functional and morphological alterations of the microvasculature in hyperglycemic and hyperinsulinemic transgenic UCP1/DTA mice with brown fat deficiency, using a dorsal skin-fold chamber preparation and fluorescence microscopy. UCP1/DTA mice showed a dramatic decrease in vascular density due to a remarkable reduction of small vessels. Vascular permeability and leukocyte endothelial interactions (LEIs) significantly increased. The extent of vascular alteration correlated with the extent of metabolic dysfunction. Decreased tissue perfusion observed in UCP1/DTA mice might play a role in impaired wound healing observed in diabetes. The increased permeability in subcutaneous tissue may serve as predictor of vascular changes in early stages of diabetes. The increased LEI and serum tumor necrosis factor-alpha levels, which mirror the inflammatory process, support the growing evidence of the inflammatory component of diabetic disease. The results suggest that anti-inflammatory strategies might be able to prevent vascular deterioration in early stages of diabetes. Further investigations are required to evaluate the benefit of such therapeutic strategies.


Assuntos
Diabetes Mellitus Experimental/sangue , Angiopatias Diabéticas/patologia , Hiperglicemia/patologia , Microcirculação/patologia , Pele/irrigação sanguínea , Animais , Glicemia/metabolismo , Vasos Sanguíneos/patologia , Temperatura Corporal , Angiopatias Diabéticas/sangue , Toxina Diftérica/genética , Teste de Tolerância a Glucose , Hiperglicemia/sangue , Camundongos , Camundongos Transgênicos , Microscopia , Fragmentos de Peptídeos/genética , Fatores de Risco
7.
Eur J Cancer ; 41(7): 1073-85, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15862758

RESUMO

Functional properties of tumour vasculature influence the process of metastasis and play a role in generating a heterogeneous metabolic microenvironment, which contributes to genetic instability and inefficiency of tumour therapies. Morphological and functional properties of tumour vasculature may vary from tumour onset to late-stage disease. The aim of this study was to identify the dynamic alteration in tumour microcirculation in a chronic observation model. Invasively-growing, non-disseminating, green fluorescent protein transfected, human bone marrow derived endothelial cells, were implanted into cranial windows of severe combined immunodeficient mice. Intravital fluorescence microscopy was performed over a period of 85 days to measure permeability, leucocyte-endothelial interaction (LEI) and tissue perfusion rate as functional parameters. Vessel density, branching pattern and scanning electron microscopy were monitored as morphological parameters. Concordant with an increasing count of transendothelial pores, the results show that the initial event following tumour cell implantation was a significant increase in the permeability of pre-existing vessels. The variations in newly formed vessels were characterised by sequentially-occurring functional and morphological alterations with the development of characteristics typical of tumour vessels, such as increased count of trifurcations and variation in vessel calibre by more than 100%. In parallel with the increasing vessel volume per area, the tissue perfusion rate increased until day 61. It is concluded from the step-specific sequential functional and morphological alterations that the efficiency of adjuvant therapies depends not only on their intrinsic efficiency but also on the timing of their initiation.


Assuntos
Neoplasias Experimentais/irrigação sanguínea , Animais , Velocidade do Fluxo Sanguíneo/fisiologia , Vasos Sanguíneos/patologia , Permeabilidade Capilar/fisiologia , Linhagem Celular Tumoral , Endotélio Vascular/imunologia , Proteínas de Fluorescência Verde/metabolismo , Leucócitos/fisiologia , Masculino , Camundongos , Camundongos SCID , Microcirculação/fisiologia , Microscopia Eletrônica de Varredura , Microscopia de Fluorescência/métodos , Transplante de Neoplasias/patologia , Neoplasias Experimentais/imunologia , Neoplasias Experimentais/patologia , Estatísticas não Paramétricas , Fatores de Tempo
8.
J Orthop Res ; 21(5): 805-12, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12919867

RESUMO

Angiogenesis is essential for wound healing and proliferative processes such as bone formation and repair. Since increased expression of the vascular endothelial growth factor (VEGF) stimulates bone formation, it can be hypothesized that surgical procedures leading to a systemic increase of VEGF for instance during wound healing, influence enchondral ossification processes and might be responsible for observed growth phenomena during callus distraction. To study the mechanisms of angiogenesis in soft tissue during unilateral callus distraction, lengthening of the right tibia was performed in 12 beagles. After osteotomy, application of a ring fixator and after five latency days, distraction was started for 25 days. A control group of four additional beagles underwent no surgical procedure. Subsequent to the distraction period (Group A), muscle samples from six beagles were taken from the distracted side (ds) and the contralateral non-distracted side (n-ds), six beagles underwent an additional consolidation period of 25 days (Group B). Samples were analyzed for VEGF, VEGFR-1 and VEGFR-2 mRNA expression using real-time PCR and protein expression using Western Blot analysis. Muscles from both extremities showed significantly increased expression of VEGF and its cognate receptors VEGFR-1/2. Expression decreased significantly after the consolidation period, whereby the level at the non-distracted side decreased more than the level at the distracted side. Interestingly VEGF and VEGFR-1 levels at the non-distracted side were significantly higher than at the distracted side. In contrast VEGFR-2, the receptor that mediates endothelial cell proliferation, showed higher levels at the distracted than at the non-distracted side. These findings indicate that callus distraction results not only in locally increased expression of VEGF and its receptors, but leads also to increased VEGF and VEGFR-1/2 levels at distant sides and might therefore be responsible for the observed growth phenomena during callus distraction.


Assuntos
Calo Ósseo/cirurgia , Fatores de Crescimento Endotelial/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Linfocinas/metabolismo , Músculo Esquelético/metabolismo , Osteogênese por Distração , Animais , Western Blotting , Sistemas Computacionais , Cães , Fatores de Crescimento Endotelial/genética , Peptídeos e Proteínas de Sinalização Intercelular/genética , Linfocinas/genética , Reação em Cadeia da Polimerase/métodos , RNA Mensageiro/metabolismo , Tíbia/cirurgia , Fator A de Crescimento do Endotélio Vascular , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/genética , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/genética , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Fatores de Crescimento do Endotélio Vascular
9.
J Neurosurg Spine ; 18(5): 496-503, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23473344

RESUMO

OBJECT: Disc-related disorders such as herniation and chronic degenerative disc disease (DDD) are often accompanied by acute or chronic pain. Different mediators have been identified in the development of radicular pain and DDD. Previous studies have not analyzed individual cytokine profiles discriminating between acute sciatic and chronic painful conditions, nor have they distinguished between different anatomical locations within the disc. The aim of this study was to elucidate the protein biochemical mechanisms in DDD. METHODS: The authors determined expression levels of matrix metalloproteinase-3, transforming growth factor-ß (TGF-ß), tumor necrosis factor-α, interleukin-1α, and pro-substance P using enzyme-linked immunosorbent assay and Western blot analyses in patients suffering from DDD (n = 7), acute back pain due to herniated discs with radiculopathy (n = 7), and a control group (n = 7). Disc tissue samples from the anulus fibrosus (AF) and nucleus pulposus (NP) were analyzed. Statistical analysis was performed using nonparametric tests. RESULTS: A distinct distribution of cytokines was found in different anatomical regions of intervertebral discs in patients with DDD and herniated NP. Increased TGF-ß levels were predominantly found in DDD. Matrix metalloproteinase-3 was increased in acute herniated disc material. Increased levels of substance P were found in patients suffering from DDD but not in patients with disc herniation. The data showed significantly higher levels of proinflammatory cytokines in the AF and NP of patients with DDD, and the expression levels in the AF were even higher than in the NP, suggesting that the inflammatory response initiates from the AF. CONCLUSIONS: These results highlight the complex mechanisms involved during disc degeneration and the need to distinguish between acute and chronic processes as well as different anatomical regions, namely the AF and NP. They also highlight potential problems in disc nucleus replacement therapies because the results suggest a biochemical link between AF and NP cytokine expression.


Assuntos
Dor Aguda/metabolismo , Quimiocinas/metabolismo , Dor Crônica/metabolismo , Degeneração do Disco Intervertebral/metabolismo , Deslocamento do Disco Intervertebral/metabolismo , Adolescente , Adulto , Quimiocinas/biossíntese , Dor Crônica/enzimologia , Feminino , Humanos , Interleucina-1alfa/biossíntese , Degeneração do Disco Intervertebral/enzimologia , Deslocamento do Disco Intervertebral/enzimologia , Masculino , Metaloproteinase 3 da Matriz/biossíntese , Pessoa de Meia-Idade , Substância P/biossíntese , Fator de Crescimento Transformador beta/biossíntese , Fator de Necrose Tumoral alfa/biossíntese , Adulto Jovem
10.
Acta Diabetol ; 47 Suppl 1: 19-27, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19367364

RESUMO

Microvascular complications are an important cause of morbidity in diabetic patients and can be detected in a significant number of patients at the time of diabetes diagnosis. However, little is known about the alterations in the microvasculature previous to the clinical manifestation of diabetes mellitus type 2. To obtain more insights into the early microvascular deterioration resulting from prediabetes, morphological and functional microvascular parameters were monitored using intravital fluorescence microscopy through a dorsal skin-fold chamber preparation in the uncoupling promotor-driven diphtheria toxin A chain (UCP1/DTA) mice. At the age of 12 weeks, the UCP1/DTA-mice were characterized by impaired glucose tolerance with concurrent unchanged fasting glucose, as well as dyslipidemia, hyperinsulinemia, hypertension and obesity. Prediabetic mice displayed combined hypertriglyceridemia and hypercholesterinemia. Associated with these prediabetic metabolic alterations, we demonstrate that microvascular density showed a dramatic decrease due to a reduction in perfused small vessels. A reduction in vascular density combined with unaltered blood flow in single vessels resulted in impaired tissue perfusion. Endothelial dysfunction with subsequently increased microvascular permeability and leukocyte-endothelium interactions were found. Our results of profound microvascular alterations at stages of normal fasting glucose underline the importance of early screening for prediabetes and associated microvascular complications.


Assuntos
Diabetes Mellitus Tipo 2/complicações , Angiopatias Diabéticas/fisiopatologia , Dislipidemias/complicações , Intolerância à Glucose/complicações , Microvasos/fisiopatologia , Estado Pré-Diabético/complicações , Animais , Velocidade do Fluxo Sanguíneo , Glicemia/metabolismo , Permeabilidade Capilar , Diabetes Mellitus Tipo 2/metabolismo , Angiopatias Diabéticas/etiologia , Angiopatias Diabéticas/metabolismo , Modelos Animais de Doenças , Dislipidemias/metabolismo , Dislipidemias/fisiopatologia , Intolerância à Glucose/metabolismo , Intolerância à Glucose/fisiopatologia , Humanos , Camundongos , Camundongos Transgênicos , Estado Pré-Diabético/metabolismo , Estado Pré-Diabético/fisiopatologia
11.
Atherosclerosis ; 200(2): 403-9, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18262188

RESUMO

OBJECTIVE: An inverse association of adiponectin with coronary heart disease (CHD) has been reported, but the results are inconsistent. We used data from the CORA study to investigate into plasma concentrations of adiponectin and factors that may mediate the link to incident CHD. DESIGN: The CORA study is a population-based case-control study on 200 women with incident CHD and 255 age-matched controls. RESULTS: Plasma concentrations of adiponectin were significantly lower in women with CHD (p<0.0001), and in women with BMI >or=25 kg/m(2) (p<0.02), even more so with central obesity (WHR >or=0.85), prevalent diabetes or insulin resistance (HOMA-IR >or=3.8), or low HDL-cholesterol (<50mg/dl), and in smokers (each p<0.0001). Adiponectin also correlated with intake of fruit and vegetables, meat and sausage and alcohol as dietary markers of cardiovascular risk. Strikingly, the trend towards lower adiponectin concentrations with increasing BMI or waist circumference was less marked than the difference of adiponectin between CHD cases and controls. In a logistic regression model the odds ratio of adiponectin of 0.943 per 1 microg/ml (CI 0.919-0.968, p<0.0001) for risk of CHD was progressively reduced by elevated WHR, obesity-related risk factors, smoking, and dietary parameters. CONCLUSIONS: Plasma adiponectin indicates protection from CHD in women that is attenuated by combined effects of central obesity and dependent risk factors, parameters of nutrition and smoking. Thus, the impact of adiponectin goes beyond its relation to central adiposity, but may also reflect independent effects of lifestyle.


Assuntos
Adiponectina/sangue , Aterosclerose/sangue , Aterosclerose/diagnóstico , Doença da Artéria Coronariana/sangue , Doença da Artéria Coronariana/diagnóstico , Adiponectina/metabolismo , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Índice de Massa Corporal , Estudos de Casos e Controles , Feminino , Humanos , Estilo de Vida , Pessoa de Meia-Idade , Fatores de Risco , Fumar
12.
Acta Orthop ; 77(3): 429-39, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16819682

RESUMO

BACKGROUND: Angiogenesis, the process of new vessel formation from a pre-existing vascular network, is essential for bone development and repair. New vessel formation and microvascular functions are crucial during bone repair, not only for sufficient nutrient supply, transport of macromolecules and invading cells, but also because they govern the metabolic microenvironment. Despite its central role, very little is known about the initial processes of vessel formation and microvascular function during bone repair. METHODS: To visualize and quantify the process of vessel formation and microvascular function during bone repair, we transplanted neonatal femora with a substantial defect into dorsal skin-fold chambers in severe combined immunodeficient (SCID) mice for continuous noninvasive in-vivo evaluation. We employed intravital microscopic techniques to monitor effective microvascular permeability, functional vascular density, blood flow rate and leukocyte flux repeatedly over 16 days. Oxytetracyclin and v. Kossa/v. Giesson staining was performed to quantify the calcification process in vivo and in vitro. RESULTS: Development of a hematoma surrounding the defect area was the initial event, which was accompanied by a significant increase in microvascular permeability and blood flow rate. With absorption of the hematoma and vessel maturation, permeability decreased continuously, while vascular density and tissue perfusion increased. Histological evaluation revealed that the remodeling of the substantial defect prolonged the in-vivo monitored calcification process. INTERPRETATION: The size of the initial substantial defect correlated positively with increased permeability, suggesting improved release of permeability-inducing cytokines. The unchanged permeability in the control group with boiled bones and a substantial defect corroborated these findings. The adaptation to increasing metabolic demands was initially mediated by increased blood flow rate, later with increasing vascular density through increased tissue perfusion rate. These insights into the sequence of microvascular alterations may assist in the development of targeted drug delivery therapies and caution against the use of permeability-altering drugs during bone healing.


Assuntos
Regeneração Óssea/fisiologia , Osso e Ossos/irrigação sanguínea , Microcirculação/fisiologia , Neovascularização Fisiológica/fisiologia , Osteogênese/fisiologia , Animais , Velocidade do Fluxo Sanguíneo/fisiologia , Transplante Ósseo/métodos , Fêmur/irrigação sanguínea , Fêmur/patologia , Fêmur/transplante , Humanos , Camundongos , Camundongos SCID
13.
Obes Res ; 13(10): 1764-71, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16286524

RESUMO

OBJECTIVE: To examine the association between plasma resistin levels and the presence of coronary heart disease (CHD) in women. RESEARCH METHODS AND PROCEDURES: Plasma resistin levels were measured in a case-control study including 185 women with angiographically confirmed CHD and 227 population-based female controls from the Coronary Risk Factors for Atherosclerosis in Women (CORA) study. RESULTS: After adjustment for age, smoking, family history of myocardial infarction, retirement, education, physical activity, menopausal status, hormone replacement use, BMI, hypertension, diabetes, and dyslipidemia, the odds ratio for CHD for women in the highest compared with lowest quintile of plasma resistin levels was 3.19 (95% confidence interval, 1.44 to 7.10; p log trend, 0.001). After additional adjustment for plasma C-reactive protein levels, this association was substantially attenuated and no longer significant (odds ratio, 1.80; 95% confidence interval, 0.69 ti 4.69; p trend = 0.23). DISCUSSION: These results suggest that plasma resistin levels are significantly associated with the presence of CHD in women; however, this association can largely be explained by concomitant inflammatory processes. Further studies are needed to determine the causal role of resistin in the development of CHD in humans.


Assuntos
Doença das Coronárias/sangue , Resistina/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Feminino , Humanos , Pessoa de Meia-Idade
14.
Genes Chromosomes Cancer ; 37(1): 79-83, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12661008

RESUMO

The ETV6 gene is a member of the ETS family of transcription factors and the main target of chromosomal rearrangements affecting chromosome band 12p13. To date, more than 15 fusion partners of ETV6 have been characterized at the molecular level. Most of these fusions encode chimeric proteins with oncogenic properties. However, some of the translocations do not produce a functional fusion protein, but may induce ectopic expression of oncogenes located close to the breakpoint. We herein report the characterization and cloning of a novel cryptic translocation, t(12;17)(p13;p12-p13), occurring in a patient with an acute myeloid leukemia evolving from a chronic myelomonocytic leukemia. Cytogenetic analysis suggested the presence of a deletion of the short arm of chromosome 12, del(12)(p13), in three of the five metaphase cells analyzed. However, fluorescence in situ hybridization (FISH) with the ETV6-specific cosmid clones 179A6, 50F4, 163E7, and 148B6 as well as probes hybridizing to the TP53 gene on 17p13 and the subtelomeric region of 17p revealed the presence of a translocation between 12p and 17p. By FISH, the breakpoints could be localized in intron 1 of ETV6 and centromeric to TP53. By 3' rapid amplification of cDNA ends-polymerase chain reaction (3' RACE-PCR), a fusion transcript between exon 1 of ETV6 and the antisense strand of PER1 (period homolog 1, Drosophila), a circadian clock gene, could be identified. This ETV6-PER1 (antisense PER1 strand) fusion transcript does not produce a fusion protein, and no other fusion transcripts could be detected. We hypothesize that in the absence of a fusion protein, the inactivation of PER1 or deregulation of a gene in the neighborhood of PER1 may contribute to the pathogenesis of leukemias with a t(12;17)(p13;p12-p13).


Assuntos
Cromossomos Humanos Par 12/genética , Cromossomos Humanos Par 17/genética , Proteínas de Ligação a DNA/genética , Leucemia Mieloide/genética , Segunda Neoplasia Primária/genética , Proteínas Nucleares/genética , Proteínas de Fusão Oncogênica/genética , Proteínas Repressoras/genética , Translocação Genética/genética , Doença Aguda , Idoso , Sequência de Bases/genética , Proteínas de Ciclo Celular , DNA Antissenso/genética , DNA de Neoplasias/genética , Humanos , Leucemia Mieloide/etiologia , Leucemia Mielomonocítica Crônica/genética , Masculino , Dados de Sequência Molecular , Proteínas Circadianas Period , Proteínas Proto-Oncogênicas c-ets , Variante 6 da Proteína do Fator de Translocação ETS
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