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1.
Osteoporos Int ; 26(1): 339-52, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25315260

RESUMO

UNLABELLED: Raman microspectroscopic analysis of iliac crest from patients that were treated with alendronate (ALN) for 10 years revealed minimal, transient alterations in bone material properties confined to actively forming bone surfaces compared to patients that were on ALN for 5 years. These changes were not encountered in the bulk tissue. INTRODUCTION: Alendronate (ALN) and other bisphosphonates (BPs) are the most widely prescribed therapy for postmenopausal osteoporosis. Despite their overall excellent safety record and efficacy in reducing fractures, questions have been raised regarding potential detrimental effects that may be related to prolonged bone turnover reduction, although no definite cause-effect relationship has been established to date. The purpose of the present study was to evaluate bone material properties in patients that were receiving ALN for 5 or 10 years. METHODS: Raman microspectroscopic analysis was used to analyze iliac crest biopsies from postmenopausal women with osteoporosis who had been treated with ALN for 5 years and were then re-randomized to placebo (PBO, N = 14), 5 mg/day ALN (N = 10), or 10 mg/day ALN (N = 6) for another 5 years. The parameters monitored and expressed as a function of tissue age were (i) the mineral/matrix ratio (MM), (ii) the relative proteoglycan content (PG), (iii) the relative lipid content (LPD), (iv) the mineral maturity/crystallinity (MMC), and (v) the relative pyridinoline content (PYD). RESULTS: The obtained data indicate that 10-year ALN use results in minimal, transient bone tissue composition changes compared to use for 5 years, confined to actively forming trabecular surfaces, implying potential differences in bone matrix maturation that nevertheless did not result in differences of these values in bulk tissue. CONCLUSIONS: The data suggest that prolonged reduction in bone turnover during 10 years of therapy with ALN by itself is unlikely to be associated with adverse effects on bone material properties.


Assuntos
Alendronato/administração & dosagem , Conservadores da Densidade Óssea/administração & dosagem , Osteoporose Pós-Menopausa/tratamento farmacológico , Alendronato/farmacologia , Alendronato/uso terapêutico , Biópsia , Conservadores da Densidade Óssea/farmacologia , Conservadores da Densidade Óssea/uso terapêutico , Remodelação Óssea/efeitos dos fármacos , Esquema de Medicação , Feminino , Humanos , Ílio/patologia , Metabolismo dos Lipídeos/fisiologia , Osteoporose Pós-Menopausa/metabolismo , Osteoporose Pós-Menopausa/patologia , Osteoporose Pós-Menopausa/fisiopatologia , Análise Espectral Raman/métodos
2.
Bone ; 69: 89-97, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25245203

RESUMO

Bone material characteristics are important contributors in the determination of bone strength. Raman spectroscopic analysis provides information on mineral/matrix ratio, mineral maturity/crystallinity, relative pyridinoline (Pyd) collagen cross-link content, relative proteoglycan content and relative lipid content. However, published reference data are available only for adults. The purpose of the present study was to establish reference data of Raman outcomes pertaining to bone quality in trabecular bone for children and young adults. To this end, tissue age defined Raman microspectroscopic analysis was performed on bone samples from 54 individuals between 1.5 and 23 years with no metabolic bone disease, which have been previously used to establish histomorphometric and bone mineralization density distribution reference values. Four distinct tissue ages, three well defined by the fluorescent double labels representing early stages of bone formation and tissue maturation (days 3, 12, 20 of tissue mineralization) and a fourth representing old mature tissue at the geometrical center of the trabeculae, were analyzed. In general, significant dependencies of the measured parameters on tissue age were found, while at any given tissue age, sex and subject age were not confounders. Specifically, mineral/matrix ratio, mineral maturity/crystallinity index and relative pyridinoline collagen cross-link content index increased by 485%, 20% and 14%, respectively between days 3 and 20. The relative proteoglycan content index was unchanged between days 3 and 20 but was elevated in the old tissue compared to young tissue by 121%. The relative lipid content decreased within days 3 to 20 by -22%. Thus, the method allows not only the monitoring of material characteristics at a specific tissue age but also the kinetics of tissue maturation as well. The established reference Raman database will serve as sensitive tool to diagnose disturbances in material characteristics of pediatric bone biopsy samples.


Assuntos
Ílio/anatomia & histologia , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Valores de Referência , Análise Espectral Raman , Adulto Jovem
3.
Osteoporos Int ; 25(12): 2709-19, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25037600

RESUMO

UNLABELLED: The results of the present study, involving analysis of biopsies from patients who received teriparatide for 2 years and were previously either treatment-naïve or on long-term alendronate therapy, suggest that prior alendronate use does not blunt the favorable effects of teriparatide on bone quality. INTRODUCTION: Examine the effect of 2 years of teriparatide (TPTD) treatment on mineral and organic matrix properties of the newest formed bone in patients who were previously treatment-naïve (TN) or on long-term alendronate (ALN) therapy. METHODS: Raman and Fourier transform infrared microspectroscopic analyses were used to determine the mineral/matrix (M/M) ratio, the relative proteoglycan (PG) content, and the mineral maturity/crystallinity (MMC; determined by three methods: carbonate content, full width at half height of the v 1 PO4 band [FWHH], and wavelength at maxima of the v 1 PO4 band), as well as collagen maturity (ratio of pyridinoline/divalent cross-links), in paired iliac crest biopsies at trabecular, endosteal, and osteonal surfaces of newly formed bone in postmenopausal osteoporotic women who were previously either TN (n = 16) or receiving long-term ALN treatment (n = 24). RESULTS: Trabecular M/M ratio increased and matrix content decreased significantly in the ALN pretreated group. Collagen maturity decreased in both patient groups. Endosteal M/M ratio increased significantly in the TN group. Trabecular M/M ratio was higher at endpoint in the ALN pretreated group than in the TN group. Overall, no changes from baseline were observed in PG content, except that PG content was higher in the ALN pretreated group than in the TN group at endosteal surfaces at endpoint. The ability of TPTD treatment to reduce MMC in both patient groups and at the different bone surfaces depended on the measurement tool (relative carbonate content or wavelength at maxima of the v 1 PO4 band). None of the changes in MMC were different between the two patient groups. CONCLUSIONS: The results suggest some favorable impact of TPTD on bone mineral and organic matrix properties of in situ forming bone in terms of increased initial mineralization and decreased MMC and collagen maturity. Moreover, prior long-term ALN administration may have only limited influence on these properties in bone newly formed after 2 years of TPTD treatment.


Assuntos
Conservadores da Densidade Óssea/farmacologia , Calcificação Fisiológica/efeitos dos fármacos , Osteoporose Pós-Menopausa/tratamento farmacológico , Teriparatida/farmacologia , Idoso , Alendronato/administração & dosagem , Alendronato/uso terapêutico , Biópsia , Densidade Óssea/efeitos dos fármacos , Conservadores da Densidade Óssea/administração & dosagem , Conservadores da Densidade Óssea/uso terapêutico , Matriz Óssea/efeitos dos fármacos , Esquema de Medicação , Substituição de Medicamentos , Feminino , Humanos , Ílio/efeitos dos fármacos , Ílio/patologia , Ílio/fisiopatologia , Pessoa de Meia-Idade , Osteoporose Pós-Menopausa/patologia , Osteoporose Pós-Menopausa/fisiopatologia , Análise Espectral Raman/métodos , Teriparatida/administração & dosagem , Teriparatida/uso terapêutico
4.
Osteoporos Int ; 24(1): 339-47, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23229465

RESUMO

UNLABELLED: Once-yearly administration of intravenous zoledronic acid for 3 years in humans affects the kinetics of matrix filling in by mineral, independent of bone turnover. INTRODUCTION: Yearly 5-mg infusions of zoledronic acid (ZOL) for 3 years have shown pronounced antifracture efficacy. The purpose of the present study was to test whether ZOL affects the kinetics of forming bone material properties maturation. METHODS: Iliac crest biopsies from the HORIZON-PFT clinical trial were analyzed by Raman microspectroscopy in actively bone-forming surfaces as a function of tissue age in trabecular and osteonal bone, to determine ZOL's effect on bone material quality indices maturation kinetics. RESULTS: Mineral/matrix ratio increased in both groups as a function of tissue age, at both osteonal- and trabecular-forming surfaces; ZOL exhibiting the greatest increase in the trabecular surfaces only. The proteoglycan content showed a dependency on tissue age in both trabecular and osteonal surfaces, with ZOL exhibiting lower values in the tissue age 8-22 days in the trabecular surfaces. Mineral crystallinity (crystallite length and thickness) showed a dependence on tissue age, with ZOL exhibiting lower crystallite length compared with placebo only in the 8- to 22-day-old tissue at trabecular surfaces, while crystal thickness was lower in the 1- to 5-day-old tissue at both osteonal and trabecular surfaces. CONCLUSIONS: The results of the present study suggest that once-yearly administration of intravenous ZOL for 3 years in humans does not exert any adverse effects on the evolution of bone material properties at actively forming osteonal and trabecular surfaces, while it may have a beneficial effect on the progression of the mineral-to-matrix ratio and mineral maturity bone quality indices.


Assuntos
Conservadores da Densidade Óssea/farmacologia , Matriz Óssea/efeitos dos fármacos , Difosfonatos/farmacologia , Imidazóis/farmacologia , Osteoporose Pós-Menopausa/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Biópsia , Densidade Óssea/efeitos dos fármacos , Conservadores da Densidade Óssea/administração & dosagem , Conservadores da Densidade Óssea/uso terapêutico , Matriz Óssea/patologia , Matriz Óssea/fisiopatologia , Difosfonatos/administração & dosagem , Difosfonatos/uso terapêutico , Esquema de Medicação , Feminino , Humanos , Imidazóis/administração & dosagem , Imidazóis/uso terapêutico , Infusões Intravenosas , Pessoa de Meia-Idade , Osteoporose Pós-Menopausa/patologia , Osteoporose Pós-Menopausa/fisiopatologia , Proteoglicanas/metabolismo , Análise Espectral Raman/métodos , Ácido Zoledrônico
5.
Oncogene ; 27(17): 2501-6, 2008 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-17982490

RESUMO

The ataxia-telangiectasia-mutated (ATM) kinase is a key transducer of DNA damage signals within the genome maintenance machinery and a tumour suppressor whose germline mutations predispose to familial breast cancer. ATM signalling is constitutively activated in early stages of diverse types of human malignancies and cell culture models in response to oncogene-induced DNA damage providing a barrier against tumour progression. As BRCA1 and BRCA2 are also components of the genome maintenance network and their mutations predispose to breast cancer, we have examined the ATM expression in human breast carcinomas of BRCA1/2 mutation carriers, sporadic cases and familial non-BRCA1/2 patients. Our results show that ATM protein expression is aberrantly reduced more frequently among BRCA1 (33%; P=0.0003) and BRCA2 (30%; P=0.0009) tumours than in non-BRCA1/2 tumours (10.7%). Furthermore, the non-BRCA1/2 tumours with reduced ATM expression were more often estrogen receptor (ER) negative (P=0.0002), progesterone receptor (PR) negative (P=0.004) and were of higher grade (P=0.0004). In our series of 1013 non-BRCA1/2 cases, ATM was more commonly deficient (20%; P=0.0006) and p53 was overabundant (47%; P<0.0000000001) among the difficult-to-treat ER/PR/ERBB2-triple-negative subset of tumours compared with cases that expressed at least one of these receptors (10 and 16% of aberrant ATM and p53, respectively). We propose a model of 'conditional haploinsufficiency' for BRCA1/2 under conditions of enhanced DNA damage in precancerous lesions resulting in more robust activation and hence increased selection for inactivation or loss of ATM in tumours of BRCA1/2 mutation carriers, with implications for genomic instability and curability of diverse subsets of human breast cancer.


Assuntos
Proteína BRCA1/deficiência , Proteína BRCA2/deficiência , Neoplasias da Mama/metabolismo , Dano ao DNA , Proteínas de Ligação a DNA/deficiência , Proteínas Serina-Treonina Quinases/deficiência , Receptor ErbB-2/deficiência , Receptores de Estrogênio/deficiência , Receptores de Progesterona/deficiência , Proteínas Supressoras de Tumor/deficiência , Proteínas Mutadas de Ataxia Telangiectasia , Proteína BRCA1/metabolismo , Proteína BRCA2/metabolismo , Neoplasias da Mama/genética , Proteínas de Ciclo Celular/metabolismo , Dano ao DNA/genética , Proteínas de Ligação a DNA/metabolismo , Humanos , Proteínas Serina-Treonina Quinases/metabolismo , Receptor ErbB-2/metabolismo , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Transdução de Sinais , Proteína Supressora de Tumor p53/metabolismo , Proteínas Supressoras de Tumor/metabolismo
7.
Anaesthesist ; 51(6): 470-4, 2002 Jun.
Artigo em Alemão | MEDLINE | ID: mdl-12391534

RESUMO

A giant hemangioma of the tongue was resected in a 16-year-old otherwise healthy young man (ASA I). Despite a total blood loss of 4,300 ml, corresponding to 105% of the patients intravascular blood volume, no allogeneic red blood cells had to be transfused intraoperatively. Besides minimization of intraoperative blood loss with preoperative alcohol injections into the tumor, ligation of large tumor-perfusing arteries, application of fibrin glue, skillful surgical technique, positioning of the surgical field above the level of the heart, controlled hypotension and maintenance of normothermia, acute normovolemic hemodilution (augmented by preoperative administration of recombinant human erythropoetin - rhEpo) and autotransfusion of lost blood were used for recovery of autologous blood. Under the protection of hyperoxia, a decrease of the hemoglobin (Hb) concentration to 4.2 g/dl was bridged by extreme normovolemic hemodilution. No signs of immanent or manifest tissue hypoxia were encountered. Retransfusion of autologous red blood cells was only started when surgical control of bleeding was achieved. Additionally a total of 4 units of fresh frozen plasma were infused for stabilization of plasma coagulation. After a 9-hour surgical duration, the patient was transferred to the intensive care unit, normotensive (with low-dose infusion of norepinephrin) and normothermic with a Hb concentration of 5.6 g/dl. In the face of an increasing lactacidosis 2 units of packed red blood cells were transfused on post surgical day 1.


Assuntos
Transfusão de Sangue Autóloga , Hemangioma/cirurgia , Neoplasias da Língua/cirurgia , Adolescente , Anestesia Geral , Perda Sanguínea Cirúrgica , Preservação de Sangue , Transfusão de Eritrócitos , Eritropoetina/uso terapêutico , Adesivo Tecidual de Fibrina , Hemodiluição , Humanos , Masculino , Plasma , Proteínas Recombinantes , Adesivos Teciduais
8.
Anesthesiology ; 82(3): 634-40, 1995 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-7879931

RESUMO

BACKGROUND: Opioids can produce peripheral analgesic effects by activation of opioid receptors on sensory nerves. This study was designed (1) to examine a novel route of opioid administration, the intraperitoneal injection; (2) to compare this to interpleural application, and (3) to compare opioid with local anesthetic effects under both conditions. METHODS: At the end of laparoscopic cholecystectomy, 110 patients received the following injections in a double-blind, randomized manner: Group 1 (n = 18) was given intraperitoneal morphine (1 mg in 20 ml saline) and 20 ml intravenous saline. Group 2 (n = 17) received intraperitoneal saline and 1 mg intravenous morphine. Group 3 (n = 15) received 20 ml 0.25% intraperitoneal bupivacaine and intravenous saline. Group 4 (n = 20) received interpleural morphine (1.5 mg in 30 ml saline) and 30 ml intravenous saline. Group 5 (n = 20) received interpleural saline and 1.5 mg intravenous morphine. Group 6 (n = 20) received 30 ml 0.25% interpleural bupivacaine and intravenous saline. Postoperative pain was assessed using a visual analog scale, a numeric rating scale, and the McGill pain questionnaire. Pain localization, supplemental analgesic consumption, vital signs, and side effects were recorded for 24 h. RESULTS: Neither intraperitoneal nor interpleural morphine produced significant analgesia after laparoscopic cholecystectomy (P > 0.05, Kruskal-Wallis test), whereas interpleural bupivacaine was effective (P < 0.05, Kruskal-Wallis test, up to 6 h postoperatively) but not intraperitoneal bupivacaine (P > 0.05, Kruskal-Wallis test). Shoulder pain was not prevalent in the majority of patients during the first 6 h. By 24 h, about half of the patients complained of shoulder pain, which was rated "low" by about one-third of all patients. No significant side effects occurred. CONCLUSIONS: Interpleural bupivacaine (0.25%) produces analgesia after laparoscopic cholecystectomy. We attribute the lack of effect of intraperitoneal injections to the small dose and to a rapid dilution within the peritoneal cavity. The fact that interpleural morphine (0.005%) is ineffective may be due to an intact perineurial barrier in the noninflamed pleural cavity, which restricts the transperineurial passage of morphine to opioid receptors on intercostal nerves.


Assuntos
Bupivacaína/administração & dosagem , Colecistectomia/métodos , Morfina/administração & dosagem , Dipirona/administração & dosagem , Método Duplo-Cego , Humanos , Injeções Intraperitoneais , Laparoscopia/métodos , Manejo da Dor , Pleura , Tramadol/administração & dosagem
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