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1.
BMC Geriatr ; 18(1): 47, 2018 02 14.
Artículo en Inglés | MEDLINE | ID: mdl-29444645

RESUMEN

BACKGROUND: Advance care planning (ACP) has been identified as particularly relevant for nursing home residents, but it remains unclear how or under what circumstances ACP works and can best be implemented in such settings. We aimed to develop a theory that outlines the hypothetical causal pathway of ACP in nursing homes, i.e. what changes are expected, by means of which processes and under what circumstances. METHODS: The Theory of Change approach is a participatory method of programme design and evaluation whose underlying intention is to improve understanding of how and why a programme works. It results in a Theory of Change map that visually represents how, why and under what circumstances ACP is expected to work in nursing home settings in Belgium. Using this approach, we integrated the results of two workshops with stakeholders (n = 27) with the results of a contextual analysis and a systematic literature review. RESULTS: We identified two long-term outcomes that ACP can achieve: to improve the correspondence between residents' wishes and the care/treatment they receive and to make sure residents and their family feel involved in planning their future care and are confident their care will be according to their wishes. Besides willingness on the part of nursing home management to implement ACP and act accordingly, other necessary preconditions are identified and put in chronological order. These preconditions serve as precursors to, or requirements for, accomplishing successful ACP. Nine original key intervention components with specific rationales are identified at several levels (resident/family, staff or nursing home) to target the preconditions: selection of a trainer, ensuring engagement by management, training ACP reference persons, in-service education for healthcare staff, information for staff, general practitioners, residents and their family, ACP conversations and documentation, regular reflection sessions, multidisciplinary meetings, and formal monitoring. ONCLUSIONS: The Theory of Change map presented here illustrates a theory of how ACP is expected to work in order to achieve its desired long-term outcomes while highlighting organisational factors that potentially facilitate the implementation and sustainability of ACP. We provide the first comprehensive rationale of how ACP is expected to work in nursing homes, something that has been called for repeatedly.


Asunto(s)
Planificación Anticipada de Atención/organización & administración , Casas de Salud/organización & administración , Anciano , Bélgica , Comunicación , Documentación , Humanos , Médicos , Relaciones Profesional-Familia , Evaluación de Programas y Proyectos de Salud
2.
Pathologe ; 29 Suppl 2: 338-46, 2008 Nov.
Artículo en Alemán | MEDLINE | ID: mdl-18810445

RESUMEN

We have recently characterized ITIH5 as a new extracellular matrix protein that exhibits clear expression loss in a variety of human tumour entities, including breast cancer. The aim of the present study was to decipher the molecular cause of ITIH5 expression loss in breast cancer and to learn more about the possible role of this molecule in cancer diseases. ITIH5 protein expression was found to be strongly reduced in 42% of invasive breast carcinomas-interestingly, with significant association with poor patient outcome. ITIH5 promoter methylation was frequently detected in breast cell lines and in primary carcinomas (40%), and it was functionally correlated with loss of ITIH5 mRNA expression. Moreover, ITIH5 promoter methylation was also significantly associated with poor clinical patient outcome and also with the occurrence of lymph node and distant metastases. In conclusion, we propose that ITIH5 may represent a novel metastasis repressor in human breast cancer. Both ITIH5 protein expression and ITIH5 promoter methylation may serve as prognostic biomarkers, thereby helping improve clinical patient outcome.


Asunto(s)
Biomarcadores de Tumor/genética , Neoplasias de la Mama/genética , Carcinoma Ductal/genética , Carcinoma Intraductal no Infiltrante/genética , Metilación de ADN/genética , Silenciador del Gen , Regiones Promotoras Genéticas/genética , Proteínas Inhibidoras de Proteinasas Secretoras/genética , Neoplasias de la Mama/patología , Carcinoma Ductal/patología , Carcinoma Intraductal no Infiltrante/patología , Línea Celular Tumoral , Progresión de la Enfermedad , Femenino , Estudios de Seguimiento , Regulación Neoplásica de la Expresión Génica/genética , Humanos , Invasividad Neoplásica , Estadificación de Neoplasias , Análisis de Secuencia por Matrices de Oligonucleótidos , Fenotipo , Pronóstico , ARN Mensajero/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
3.
S Afr Med J ; 107(4): 352-353, 2017 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-28395690

RESUMEN

BACKGROUND: Studies that identify factors associated with intervention uptake are urgently needed in poorly resourced healthcare systems. This is important, as knowing who is likely to engage may lead to intervention targeting, which is an efficient use of scarce health resources. OBJECTIVE: To identify patient characteristics that predict the acceptance of a brief intervention for substance use delivered in emergency departments (EDs). METHODS: Patients presenting to three EDs were screened for substance use using the Alcohol, Smoking, and Substance Involvement Screening Test (ASSIST). All patients identified as at risk for substance use problems were offered a brief psychotherapy intervention focused on substance user education. Data were collected on patients' age, sex, presenting condition (injury/no injury), type of substance used, and severity of substance use. Logistic regression analysis was used to identify variables that predicted acceptance of the offer of a brief intervention. RESULTS: Being between the ages of 25 and 39 years increased the likelihood of accepting an offer of help compared with 18 - 24-year-olds. Polysubstance users were less likely to accept an offer of help than patients with problematic alcohol use only, while patients with higher ASSIST scores were more likely to accept an offer of help than those with lower scores. CONCLUSIONS: Findings suggest that more work is needed to understand the mechanisms underlying treatment acceptance. Brief interventions delivered in ED services in countries such as South Africa should target alcohol users with higher ASSIST scores in order to ensure the efficient use of scarce health resources.

4.
Opt Express ; 14(4): 1596-603, 2006 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-19503487

RESUMEN

We report smooth and broad continuum generation using a compact femtosecond Ti:Sapphire laser as a pump source and a tapered photonic crystal fibre as a nonlinear element. Spectral output is optimized for use in optical coherence tomography, providing a maximum longitudinal resolution of 1.5 microm in free space at 809 nm centre wavelength without use of additional spectral filtering.

5.
Artículo en Inglés | MEDLINE | ID: mdl-28596888

RESUMEN

BACKGROUND: The prevalence of depression in rural Ugandan communities is high and yet detection and treatment of depression in the primary care setting is suboptimal. Short valid depression screening measures may improve detection of depression. We describe the validation of the Luganda translated nine- and two-item Patient Health Questionnaires (PHQ-9 and PHQ-2) as screening tools for depression in two rural primary care facilities in Eastern Uganda. METHODS: A total of 1407 adult respondents were screened consecutively using the nine-item Luganda PHQ. Of these 212 were randomly selected to respond to the Mini International Neuropsychiatric Interview diagnostic questionnaire. Descriptive statistics for respondents' demographic characteristics and PHQ scores were generated. The sensitivity, specificity and positive predictive values (PPVs), and area under the ROC curve were determined for both the PHQ-9 and PHQ-2. RESULTS: The optimum trade-off between sensitivity and PPV was at a cut-off of ≧5. The weighted area under the receiver Operating Characteristic curve was 0.74 (95% CI 0.60-0.89) and 0.68 (95% CI 0.54-0.82) for PHQ-9 and PHQ-2, respectively. CONCLUSION: The Luganda translation of the PHQ-9 was found to be modestly useful in detecting depression. The PHQ-9 performed only slightly better than the PHQ-2 in this rural Ugandan Primary care setting. Future research could improve on diagnostic accuracy by considering the idioms of distress among Luganda speakers, and revising the PHQ-9 accordingly. The usefulness of the PHQ-2 in this rural population should be viewed with caution.

6.
Oncogene ; 34(13): 1667-78, 2015 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-24769898

RESUMEN

Deregulation of the transforming acidic coiled-coil protein 3 (TACC3), an important factor in the centrosome-microtubule system, has been linked to a variety of human cancer types. We have recently reported on the oncogenic potential of TACC3; however, the molecular mechanisms by which TACC3 mediates oncogenic function remain to be elucidated. In this study, we show that high levels of TACC3 lead to the accumulation of DNA double-strand breaks (DSBs) and disrupt the normal cellular response to DNA damage, at least in part, by negatively regulating the expression of ataxia telangiectasia mutated (ATM) and the subsequent DNA damage response (DDR) signaling cascade. Cells expressing high levels of TACC3 display defective checkpoints and DSB-mediated homologous recombination (HR) and non-homologous end joining (NHEJ) repair systems, leading to genomic instability. Importantly, high levels of TACC3 confer cellular sensitization to radiation and poly(ADP-ribose) polymerase (PARP) inhibition. Overall, our findings provide critical information regarding the mechanisms by which TACC3 contributes to genomic instability, potentially leading to cancer development, and suggest a novel prognostic, diagnostic and therapeutic strategy for the treatment of cancer types expressing high levels of TACC3.


Asunto(s)
Daño del ADN , Proteínas Asociadas a Microtúbulos/fisiología , Inhibidores de Poli(ADP-Ribosa) Polimerasas , Tolerancia a Radiación , Aberraciones Cromosómicas , Roturas del ADN de Doble Cadena , Humanos , Proteínas Asociadas a Microtúbulos/análisis , Neoplasias/genética
7.
Bone ; 16(5): 511-20, 1995 May.
Artículo en Inglés | MEDLINE | ID: mdl-7654466

RESUMEN

Some geminal bisphosphonates are used clinically in a number of important bone and calcium-related diseases. This work reports the anticalcification and antiresorption effects of a series of bisacylphosphonates, nongeminal compounds with varying chain lengths having oxo groups in alpha positions relative to the phosphonic functions. We compared the activity of the novel compounds to clinically used geminal bisphosphonates, and to a bisphosphonate devoid of the oxo groups. The interaction of the compounds with calcium was studied by various in vitro and in vivo models. We found that keto groups in alpha positions to the phosphonic functions render activity. The bisacylphosphonates with a shorter chain [(CH2)n, = 4, 6] were found significantly to inhibit hydroxyapatite formation and dissolution in vitro, the calcification of bioprosthetic tissue implanted subdermally in rats, and bone resorption in the intact young animal model. The various in vitro results were found to be in good correlation with the in vivo results. Structure-activity relationship studies indicate that both bisacylphosphonates and geminal bisphosphonates are active only when at least three ionizable groups are present in the molecule. The role of the keto groups is related to their contribution to chelating calcium and/or to their electron-withdrawing influence on acidity.


Asunto(s)
Resorción Ósea/tratamiento farmacológico , Calcinosis/tratamiento farmacológico , Difosfonatos/uso terapéutico , Acilación , Adsorción , Animales , Simulación por Computador , Difosfonatos/administración & dosificación , Difosfonatos/química , Difosfonatos/farmacología , Modelos Animales de Enfermedad , Femenino , Válvulas Cardíacas/efectos de los fármacos , Válvulas Cardíacas/metabolismo , Cetonas/química , Riñón/efectos de los fármacos , Riñón/metabolismo , Hígado/efectos de los fármacos , Hígado/metabolismo , Espectroscopía de Resonancia Magnética , Modelos Moleculares , Ratas , Espectrofotometría Atómica , Relación Estructura-Actividad , Tibia/efectos de los fármacos , Tibia/metabolismo
8.
Eur J Cancer ; 38(4): 578-85, 2002 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11872353

RESUMEN

Studies from six regions of Germany (Aachen (W1), Dresden (E1), Jena (E2), Marburg (W2), Munich (W3), and Stuttgart (C1)) have been compared to verify and assess the quality of healthcare using breast cancer as an example. All of the data collection was carried out in comprehensive cancer centres and is population-based, with the exception of C1. Classic prognostic factors and the initial treatment of 8661 women with breast cancer, diagnosed between 1996 and 1998, were examined. Primary therapy, breast conserving therapy (BCT), and the use of subsequent local radiation and/or systemic therapy (chemotherapy or hormonal therapy) were analysed. BCT was performed on 39.3-57.7% of patients. By pT-category, the proportion of BCT in the six regions were as follows: for pTis between 37.8 and 64.3%, for pT1 between 51.7 and 71.5%, for pT2 between 25.9 and 51.1%, for pT3 between 0 and 13.1% and for pT4 between 0 and 15.2%. Multivariate analyses, adjusted for age and biological factors, showed a significant influence of the treating hospital on the mastectomy rate. The use of radiotherapy after BCT (80%) was quite homogeneous in the six regions. The application of radiotherapy after mastectomy, however, varied between 10.4 and 32.2%. In all regions, for premenopausal patients, the use of adjuvant systemic therapy almost reflected the St. Gallen-Consensus recommendations. In contrast, post-menopausal women with positive lymph nodes were not always treated according to these standards. In all regions, age had an influence on the administration of treatment: elderly breast cancer patients received less BCT, less radiotherapy and less adjuvant therapy than recommended in the St. Gallen-Consensus. Feedback of the results was made available to each hospital, providing a comparative summary of patient care that could be used by the participating hospitals for self-assessment and quality-control.


Asunto(s)
Neoplasias de la Mama/terapia , Distribución por Edad , Anciano , Antineoplásicos/uso terapéutico , Neoplasias de la Mama/epidemiología , Neoplasias de la Mama/patología , Recolección de Datos , Femenino , Alemania/epidemiología , Humanos , Mastectomía/métodos , Persona de Mediana Edad , Análisis Multivariante , Garantía de la Calidad de Atención de Salud , Calidad de la Atención de Salud
9.
J Med Chem ; 26(1): 30-4, 1983 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-6298419

RESUMEN

A series of aldehydo sugars was subjected to condensation reactions with active methylene compounds. Acetylacetone was condensed with 2,4-O-benzylidene-3,5-O-dibenzoyl-D-ribose (1), 2,4:3,5-O-dibenzylidene-D-ribose (6), 2,3,4,5-tetraacetyl-D-ribose (7), and 2,3,4,5,6-pentaacetyl-D-glucose (9) to yield 3-ylidene-2,4-pentanedione derivatives 2, 11, 12, and 13, respectively. Sugar derivatives 1 and 6 were also condensed with benzoylacetone to give 14 and 18, with acetoacetanilide to give 16 and 19, with malononitrile to give 17 and 20, and with alpha-(gamma-butyrolactonylidene)triphenylphosphorane to give 21 and 22, respectively. Condensation of 1 with dibenzoylmethane gave 15. The double bond in compounds 2 and 11 was saturated by hydrogenation to give 23 and 24. All alpha, beta-unsaturated carbonyl compounds obtained exhibited antiviral activity and cytotoxicity. Compound 11 was found to have the most significant and selective antiviral activity against herpes simplex virus.


Asunto(s)
Alquenos/síntesis química , Antivirales/síntesis química , Alquenos/farmacología , Animales , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Chlorocebus aethiops , ADN/biosíntesis , ADN Viral/biosíntesis , Humanos , Riñón , Simplexvirus/efectos de los fármacos , Relación Estructura-Actividad , Ensayo de Placa Viral
10.
J Med Chem ; 43(20): 3641-52, 2000 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-11020278

RESUMEN

This work was aimed at improving the absorption of bisphosphonates by targeting carrier systems in the intestine and the intestinal peptide carrier system (hPEPT1), in particular. (14)C-Labeled pamidronate and alendronate as well as radiolabeled and "cold" peptidyl-bisphosphonates, Pro-[(3)H]Phe-[(14)C]pamidronate, and Pro-[(3)H]Phe-[(14)C]alendronate were synthesized. In situ single-pass perfusion studies revealed competitive inhibition of transport by Pro-Phe, suggesting peptide carrier-mediated transport. Prodrug transport in the Caco-2 cell line was significantly better than that of the parent drugs, and the prodrugs exhibited high affinity to the intestinal tissue. Oral administration of the dipeptidyl prodrugs resulted in a 3-fold increase in drug absorption following oral administration in rats, and the bioavailability of Pro-Phe-alendronate was 3.3 (F(TIBIA)) and 1.9 (F(URINE)) times higher than that of the parent drug. The results indicate that the oral absorption of bisphosphonates can be improved by peptidyl prodrugs via the hPEPT1; however, other transporters may also be involved.


Asunto(s)
Alendronato/administración & dosificación , Alendronato/síntesis química , Dipéptidos/síntesis química , Difosfonatos/administración & dosificación , Difosfonatos/síntesis química , Profármacos/síntesis química , Simportadores , Administración Oral , Alendronato/análogos & derivados , Alendronato/química , Alendronato/farmacocinética , Animales , Disponibilidad Biológica , Células CACO-2 , Proteínas Portadoras/metabolismo , Precipitación Química , Dipéptidos/química , Dipéptidos/farmacocinética , Difosfonatos/química , Difosfonatos/farmacocinética , Durapatita/química , Humanos , Inyecciones Intravenosas , Absorción Intestinal , Pamidronato , Transportador de Péptidos 1 , Profármacos/química , Profármacos/farmacocinética , Ratas , Distribución Tisular
11.
Biomaterials ; 22(18): 2501-6, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11516082

RESUMEN

Epoxy crosslinking agents have been investigated for use in the fabrication of bioprosthetic devices, such as heterograft heart valve prostheses. It has been generally assumed that epoxy crosslinking takes place via amino-epoxy reactions. The present study investigated the hypothesis that the reactions of methionine residues with epoxides also can occur in biomaterial crosslinking. A series of model reactions were studied in which a mono-epoxide was combined with individual alkyl sulfides. In the present studies epoxides rapidly alkylate aliphatic sulfides, including methionine derivatives, in buffered aqueous solutions at room temperature and pH close to neutral, forming sulfonium compounds, which are stable at pH 5-7 at temperatures up to 50 degrees C, except for cases in which methionine derivatives with non-protected carboxy groups are used. The rate of reaction remains practically unchanged within the range of pH from 5 to 12, whereas in strongly alkaline media the reverse reaction occurs. This discovery can provide a better understanding of processes occurring in the fixation of bioprosthetic tissues with polyepoxides. It can also develop into a site-specific method to label methionine residues in proteins. The carboxy group-containing sulfonium betaines derived from N-protected methionines undergo cyclization in unexpectedly mild conditions, which can be used as an efficient method for preparation of N-protected 2-amino-4-butyrolactones with sensitive protective groups.


Asunto(s)
Materiales Biocompatibles/química , Colágeno/química , Fijación del Tejido/métodos , 4-Butirolactona/análogos & derivados , 4-Butirolactona/síntesis química , 4-Butirolactona/química , Animales , Bioprótesis , Reactivos de Enlaces Cruzados/química , Compuestos Epoxi/química , Fijadores/química , Humanos , Concentración de Iones de Hidrógeno , Técnicas In Vitro , Espectroscopía de Resonancia Magnética , Ensayo de Materiales , Metionina/química , Sulfuros/química
12.
J Pharm Sci ; 81(10): 1004-7, 1992 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-1432609

RESUMEN

Some geminal bisphosphonates are used clinically for a number of important bone- and/or calcium-related diseases; however, side effects and lack of selectivity impede their wide use. This work reports the synthesis and evaluation of bishydroxyiminophosphonates (e.g., adipoyl- and suberoylbisphosphonate dioximes). These compounds significantly inhibited hydroxyapatite formation and dissolution in vitro and the calcification of bioprosthetic tissue implanted subdermally in rats. The compounds reported in this paper are less active than the structurally related bisacylphosphonates. The results of this work indicate that the introduction of oxime groups adjacent to the phosphonic function in long-chain bisphosphonates confers calcium interaction capabilities and that complete ionizability of a bisphosphonate may enhance its biological activity.


Asunto(s)
Calcinosis/tratamiento farmacológico , Difosfonatos/síntesis química , Animales , Bioprótesis , Calcio/metabolismo , Bovinos , Difosfonatos/farmacología , Prótesis Valvulares Cardíacas , Técnicas In Vitro , Ratas
13.
J Pharm Sci ; 77(2): 145-8, 1988 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-3258910

RESUMEN

The metabolic fate of aprophen hydrochloride (2-diethylaminoethyl 2,2-diphenylpropionate) was studied in rats after intravenous administration. Both 14C-labeled and unlabeled aprophen were used in these studies. Blood samples were collected and analyzed to determine the identities of the metabolites formed. Utilizing high-performance liquid chromatography, desethylaprophen was identified as a major metabolite in ether-extracted samples from rats, and could be detected in blood samples 1 min after intravenous administration. It was most likely formed by N-de-ethylation of aprophen by a cytochrome P-450-dependent monooxygenase. Synthetic desethylaprophen was found to possess cholinolytic activity (i.e., it functioned as a muscarinic antagonist by blocking the contraction of acetylcholine-stimulated guinea pig ileum, the release of alpha-amylase from pancreatic acinar cells stimulated by carbachol, and also by inhibiting the binding of [3H]N-methyl scopolamine to the muscarinic receptors of guinea pig ileum). It was interesting that although the biological effects of desethylaprophen were 100-fold lower than those of aprophen, it was equally able to compete for the binding sites of muscarinic receptors of the guinea pig ileum.


Asunto(s)
Parasimpatolíticos , Fenilpropionatos/metabolismo , Fenilpropionatos/farmacología , Animales , Cobayas , Íleon/efectos de los fármacos , Técnicas In Vitro , Masculino , Contracción Muscular/efectos de los fármacos , Páncreas/efectos de los fármacos , Páncreas/metabolismo , Ratas , Ratas Endogámicas , Receptores Muscarínicos/metabolismo , alfa-Amilasas/metabolismo
14.
J Pharm Sci ; 86(3): 283-9, 1997 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9050794

RESUMEN

The biological effects of bisphosphonates in calcium-related disorders are attributed to the incorporation of the bisphosphonates in bone, enabling direct interaction with osteoclasts and/or osteoblasts. The high accumulation of bisphosphonates in bone, due to their high affinity to hydroxyapatite (HAP), is essential for mediating in vitro and in vivo activity. In this study we examined the activity of tetrakisphosphonates, molecules containing two P-C-P type bisphosphonate moieties connected by a carbon chain. The novel compounds were examined in a battery of in vitro and in vivo models including HAP formation and dissolution, ectopic calcification, bone resorption, tumor osteolysis, and of macrophage-like cells (anti- or pro-inflammatory properties). The inhibition of ectopic calcification was ranked as follows: geminal bisphosphonates > bisacylphosphonates > tetrakisphosphonates. Pamidronate, but not the tetrakisphosphonates, was an effective antiosteolytic agent. Neither DNTP (tetrasodium 1,9-dihydroxynonane 1,1,9,9-tetrakisphosphonate) nor the bisacylphosphonate, PiBP (pimeloylbisphosphonate) seem to possess strong macrophage suppressive or inductive effects and can be considered to be relatively inactive in terms of anti- or pro-inflammatory action. A significant anticalcification effect was caused by various phosphonates, such as the tetrakisphosphonates, but DNTP, a tetrakisphosphonate, was found toxic as it impeded somatic growth and bone development.


Asunto(s)
Resorción Ósea/inducido químicamente , Calcinosis/prevención & control , Carcinoma 256 de Walker/tratamiento farmacológico , Difosfonatos/farmacología , Osteólisis/prevención & control , Animales , Bioprótesis , Calcinosis/patología , Carcinoma 256 de Walker/patología , Línea Celular , Supervivencia Celular/efectos de los fármacos , Difosfonatos/síntesis química , Difosfonatos/toxicidad , Durapatita/química , Ácido Etidrónico/farmacología , Femenino , Macrófagos/efectos de los fármacos , Ratones , Osteólisis/patología , Pamidronato , Ratas , Ratas Wistar
15.
J Periodontol ; 71(10): 1607-12, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11063394

RESUMEN

BACKGROUND: Periodontal surgery stimulates osteoclast activity, leading to varying amounts of alveolar crest loss. We have established that topical application of 20 mg/ml of alendronate placed at the surgical mucoperiosteal site produced a striking reduction of alveolar bone loss in the rat model. The aim of this investigation was to examine the antiresorptive efficacy of 3 novel bisacylphosphonates topically delivered at the surgical site, in comparison to alendronate and etidronate which are in clinical use. METHODS: Mucoperiosteal flap (MF) surgery was performed on the buccal and lingual aspects next to molars on both sides of the rat mandible. A gelatin sponge soaked in the bisphosphonate solution prepared by dissolving 20 mg of the bisphosphonate (alendronate, etidronate, VS-5, VS-6, ISA-13, SuBP) in 1 ml of saline was applied to exposed bone on the right side of the mandible (experimental, MF + BPs ) and the left side was treated with saline only (control, MF + S). Sections were evaluated for bone loss using microradiography pattern and amount. RESULTS: The 3 novel bisacylphosphonates, VS-5 VS-6, and ISA-13 were more effective than etidronate, and less effective than alendronate. The most effective among this group was ISA-13 followed by VS-5 and VS-6. CONCLUSION: We conclude that ISA-13-like alendronate is effective in reducing alveolar bone loss when delivered at surgical sites. Since ISA-13 is well absorbed through mucose tissues, we suggest that ISA-13 efficacy on reducing bone loss should be tested by its application on the mucosal tissue.


Asunto(s)
Pérdida de Hueso Alveolar/prevención & control , Difosfonatos/administración & dosificación , Modelos Animales de Enfermedad , Compuestos Heterocíclicos/administración & dosificación , Administración Tópica , Alendronato/administración & dosificación , Pérdida de Hueso Alveolar/diagnóstico por imagen , Proceso Alveolar/diagnóstico por imagen , Proceso Alveolar/efectos de los fármacos , Animales , Distribución de Chi-Cuadrado , Evaluación Preclínica de Medicamentos , Ácido Etidrónico/administración & dosificación , Microrradiografía , Análisis Multivariante , Ratas , Ratas Wistar
16.
J Periodontol ; 70(8): 893-5, 1999 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10476897

RESUMEN

BACKGROUND: Recently, we have shown that local delivery of alendronate reduced significantly bone resorption activated by surgical separation of periosteum from bone. These results advocate the use of local application of alendronate in bone surgeries to prevent regional bone resorption at the surgery site. Here we investigated the efficacy of absorbtion of alendronate by the bone from a gelatin sponge soaked with radiolabeled alendronate applied topically at the surgical site. METHODS: Following elevation of the mucoperiosteal flap next to premolars and molars of the rat mandible, a gelatin sponge soaked with 10 microl of radiolabled alendronate (1 microCi/mg) was applied to exposed bone on one side. The local absorbtion of alendronate and its disposition in the contralateral side of the mandible as well as in the tibia bone were analyzed. RESULTS: The results show that 10% of total alendronate content of the gelatin sponge was absorbed in the bone locally (in the surgical site), while 0.2% was disposed in the tibia. Of interest is the fact that the surgical wound in the contralateral side increased the disposition of alendronate up to 2%. This finding is most likely the result of extravasation and diffusion of alendronate due to surgical wounding. CONCLUSION: This study strongly supports our notion that local delivery of alendronate and its affinity to bone may become a very important treatment modality to prevent resorption of bone during dental and orthopedic procedures.


Asunto(s)
Alendronato/farmacocinética , Resorción Ósea/prevención & control , Osteotomía/efectos adversos , Absorción , Administración Tópica , Alendronato/administración & dosificación , Alendronato/uso terapéutico , Animales , Resorción Ósea/etiología , Mandíbula/metabolismo , Ratas , Ratas Wistar , Tibia/metabolismo , Distribución Tisular
17.
Mar Pollut Bull ; 48(1-2): 12-25, 2004 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-14725872

RESUMEN

The exploration and production of North Sea oil and gas reserves has resulted in the accumulation of large quantities of drill cuttings on the seabed surrounding drill sites. This complex mixture of man-made and natural substances contains higher concentrations of certain metals (Ba, Cr, Cu, Ni, Pb, and Zn) and hydrocarbons than are observed in background sediments. With decommissioning of older platforms underway, an evaluation of the environmental interactions and chemical fate of the drill cuttings accumulations is required. This review concentrates on contaminants within drill cutting accumulations in the Northern and Central North Sea (56 degrees N-62 degrees N). Present literature reviewed reveals that hydrocarbons within the cuttings piles remain relatively unchanged with time. A considerable proportion of the associated contaminants are likely to remain within the cuttings pile unless they are disturbed which will then increase exchanges of porewater and solids back to the seabed surface resulting in pathways of exposure for organisms.


Asunto(s)
Hidrocarburos/análisis , Industrias , Metales Pesados/análisis , Petróleo , Contaminantes del Agua/análisis , Monitoreo del Ambiente , Sedimentos Geológicos/química , Mar del Norte , Porosidad
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