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Medicinas Complementárias
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1.
Drug Test Anal ; 15(2): 173-180, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36218291

RESUMEN

Higenamine is an alkaloid found within plant species including some that are used in traditional Asian and Chinese herbal medicines. Identified as having mixed mode adrenergic receptor activity, higenamine is present within some nutritional supplements marketed for stimulant and/or weight loss. Its inclusion within nutritional supplements can be via its natural presence within botanical ingredients or as a synthetic additive, often added in mg amounts. The World Anti-doping Agency (WADA) prohibited list has contained higenamine since 2017 as banned at all times in the beta-2 agonist (S3) category, with a reporting level of 10 ng/ml for the free parent form in urine. In this study, an investigation into the content of beetroot or beetroot-containing foodstuffs and supplement products was conducted. Higenamine was confirmed as present within the majority of foodstuffs and supplements, with experimental evidence that higenamine can arise within beetroot extracts through heating. The results in this paper demonstrate the first reported evidence of a link between beetroot and this WADA prohibited substance. To investigate the link between intake and excretion, concentrated beetroot drinks were consumed by six individuals and higenamine quantified in their urine. Free higenamine was detected in the urine of all individuals, with maximum measured concentration in samples of less than 1% of the current WADA reporting limit. Although the risk of an inadvertent doping violation by consumption of the foodstuffs and products investigated in this study is low, beetroot as a source of higenamine should be considered by athletes.


Asunto(s)
Alcaloides , Doping en los Deportes , Tetrahidroisoquinolinas , Humanos , Alcaloides/orina , Tetrahidroisoquinolinas/orina , Atletas , Suplementos Dietéticos
2.
ALTEX ; 39(2): 297­314, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35064273

RESUMEN

Complex in vitro models (CIVM) offer the potential to improve pharmaceutical clinical drug attrition due to safety and/ or efficacy concerns. For this technology to have an impact, the establishment of robust characterization and qualifi­cation plans constructed around specific contexts of use (COU) is required. This article covers the output from a workshop between the Food and Drug Administration (FDA) and Innovation and Quality Microphysiological Systems (IQ MPS) Affiliate. The intent of the workshop was to understand how CIVM technologies are currently being applied by pharma­ceutical companies during drug development and are being tested at the FDA through various case studies in order to identify hurdles (real or perceived) to the adoption of microphysiological systems (MPS) technologies, and to address evaluation/qualification pathways for these technologies. Output from the workshop includes the alignment on a working definition of MPS, a detailed description of the eleven CIVM case studies presented at the workshop, in-depth analysis, and key take aways from breakout sessions on ADME (absorption, distribution, metabolism, and excretion), pharmacology, and safety that covered topics such as qualification and performance criteria, species differences and concordance, and how industry can overcome barriers to regulatory submission of CIVM data. In conclusion, IQ MPS Affiliate and FDA scientists were able to build a general consensus on the need for animal CIVMs for preclinical species to better determine species concordance. Furthermore, there was acceptance that CIVM technologies for use in ADME, pharmacology and safety assessment will require qualification, which will vary depending on the specific COU.


Asunto(s)
Alternativas a las Pruebas en Animales , Dispositivos Laboratorio en un Chip , Animales , Evaluación Preclínica de Medicamentos , Industria Farmacéutica , Preparaciones Farmacéuticas/metabolismo , Estados Unidos , United States Food and Drug Administration
3.
Br J Nutr ; 127(3): 321-334, 2022 02 14.
Artículo en Inglés | MEDLINE | ID: mdl-33749571

RESUMEN

A12-week experiment was conducted to evaluate the influences of thiamine ongrowth performance, and intestinal mitochondrial biogenesis and function of Megalobramaamblycephala fed a high-carbohydrate (HC) diet. Fish (24·73 (sem 0·45) g) were randomly assigned to one of four diets: two carbohydrate (CHO) levels (30 and 45 %) and two thiamine levels (0 and 1·5 mg/kg). HC diets significantly decreased DGC, GRMBW, FIMBW, intestinal activities of amylase, lipase, Na+, K+-ATPase, CK, complexes I, III and IV, intestinal ML, number of mitochondrial per field, ΔΨm, the P-AMPK: T-AMPK ratio, PGC-1ß protein expression as well as the transcriptions of AMPKα1, AMPKα2, PGC-1ß, mitochondrial transcription factor A, Opa-1, ND-1 and COX-1 and 2, while the opposite was true for ATP, AMP and reactive oxygen species, and the transcriptions of dynamin-related protein-1, fission-1 and mitochondrial fission factor. Dietarythiamine concentrations significantly increased DGC, GRMBW, intestinal activities of amylase, Na+, K+-ATPase, CK, complexes I and IV, intestinal ML, number of mitochondrial per field, ΔΨm, the P-AMPK:T-AMPK ratio, PGC-1ß protein expression as well as the transcriptions of AMPKα1, AMPKα2, PGC-1ß, Opa-1, ND-1, COX-1 and 2, SGLT-1 and GLUT-2. Furthermore, a significant interaction between dietary CHO and thiamine was observed in DGC, GRMBW, intestinal activities of amylase, CK, complexes I and IV, ΔΨm, the AMP:ATP ratio, the P-AMPK:T-AMPK ratio, PGC-1ß protein expression as well as the transcriptions of AMPKα1, AMPKα2, PGC-1ß, Opa-1, COX-1 and 2, SGLT-1 and GLUT-2. Overall, thiamine supplementation improved growth performance, and intestinal mitochondrial biogenesis and function of M. amblycephala fed HC diets.


Asunto(s)
Carbohidratos de la Dieta , Biogénesis de Organelos , Proteínas Quinasas Activadas por AMP/metabolismo , Adenosina Monofosfato , Adenosina Trifosfatasas/metabolismo , Adenosina Trifosfato/metabolismo , Amilasas/metabolismo , Animales , Carbohidratos de la Dieta/metabolismo , Carbohidratos de la Dieta/farmacología , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma/metabolismo , Tiamina/farmacología
4.
Clin Transl Sci ; 14(5): 1659-1680, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-33982436

RESUMEN

Nonclinical testing has served as a foundation for evaluating potential risks and effectiveness of investigational new drugs in humans. However, the current two-dimensional (2D) in vitro cell culture systems cannot accurately depict and simulate the rich environment and complex processes observed in vivo, whereas animal studies present significant drawbacks with inherited species-specific differences and low throughput for increased demands. To improve the nonclinical prediction of drug safety and efficacy, researchers continue to develop novel models to evaluate and promote the use of improved cell- and organ-based assays for more accurate representation of human susceptibility to drug response. Among others, the three-dimensional (3D) cell culture models present physiologically relevant cellular microenvironment and offer great promise for assessing drug disposition and pharmacokinetics (PKs) that influence drug safety and efficacy from an early stage of drug development. Currently, there are numerous different types of 3D culture systems, from simple spheroids to more complicated organoids and organs-on-chips, and from single-cell type static 3D models to cell co-culture 3D models equipped with microfluidic flow control as well as hybrid 3D systems that combine 2D culture with biomedical microelectromechanical systems. This article reviews the current application and challenges of 3D culture systems in drug PKs, safety, and efficacy assessment, and provides a focused discussion and regulatory perspectives on the liver-, intestine-, kidney-, and neuron-based 3D cellular models.


Asunto(s)
Alternativas al Uso de Animales/métodos , Técnicas de Cultivo Tridimensional de Células , Evaluación Preclínica de Medicamentos/métodos , Alternativas al Uso de Animales/normas , Células Cultivadas , Técnicas de Cocultivo , Evaluación Preclínica de Medicamentos/normas , Humanos , Intestinos/citología , Riñón/citología , Hígado/citología , Neuronas , Esferoides Celulares , Pruebas de Toxicidad/métodos , Pruebas de Toxicidad/normas , Estados Unidos , United States Food and Drug Administration/normas
5.
Hypertens Res ; 44(8): 941-954, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-33972751

RESUMEN

Dietary intake of the heavy metal cadmium (Cd2+) is implicated in hypertension, but potassium supplementation reportedly mitigates hypertension. This study aims to elucidate the hypertensive mechanism of Cd2+. Vascular reactivity and protein expression were assessed in Cd2+-exposed rats for 8 weeks to determine the calcium-handling effect of Cd2+ and the possible signaling pathways and mechanisms involved. Cd2+ induced hypertension in vivo by significantly (p < 0.001) elevating systolic blood pressure (160 ± 2 and 155 ± 1 vs 120 ± 1 mm Hg), diastolic blood pressure (119 ± 2 and 110 ± 1 vs 81 ± 1 mm Hg), and mean arterial pressure (133 ± 2 and 125 ± 1 vs 94 ± 1 mm Hg) (SBP, DBP, and MAP, respectively), while potassium supplementation protected against elevation of these parameters. The mechanism involved augmentation of the phosphorylation of renal myosin light chain phosphatase targeting subunit 1 (MYPT1) at threonine 697 (T697) (2.58 ± 0.36 vs 1 ± 0) and the expression of p44 mitogen-activated protein kinase (MAPK) (1.78 ± 0.20 vs 1 ± 0). While acetylcholine (ACh)-induced relaxation was unaffected, 5 mg/kg b.w. Cd2+ significantly (p < 0.001) attenuated phenylephrine (Phe)-induced contraction of the aorta, and 2.5 mg/kg b.w. Cd2+ significantly (p < 0.05) augmented sodium nitroprusside (SNP)-induced relaxation of the aorta. These results support the vital role of the kidney in regulating blood pressure changes after Cd2+ exposure, which may be a key drug target for hypertension management. Given the differential response to Cd2+, it is apparent that its hypertensive effects could be mediated by myosin light chain phosphatase (MLCP) inhibition via phosphorylation of renal MYPT1-T697 and p44 MAPK. Further investigation of small arteries and the Rho-kinase/MYPT1 interaction is recommended.


Asunto(s)
Cadmio , Hipertensión , Animales , Cadmio/toxicidad , Hipertensión/inducido químicamente , Riñón/metabolismo , Proteínas Quinasas Activadas por Mitógenos , Fosfatasa de Miosina de Cadena Ligera/metabolismo , Fosforilación , Ratas , Treonina , Quinasas Asociadas a rho/metabolismo
6.
Drug Test Anal ; 13(1): 122-127, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32748554

RESUMEN

Selective androgen receptor modulators (SARMs) are compounds with specific androgenic properties investigated for the treatment of conditions such as muscle wasting diseases. The reported androgenic properties have resulted in their use by athletes, and consequently they have been on the World Anti-Doping Agency prohibited list for more than a decade. SARMs have been investigated by pharmaceutical companies as potential drug candidates, but to date no SARM has demonstrated sufficient safety and efficacy to gain clinical approval by either the European Medicines Agency or the U.S. Food and Drug Administration. Despite their lack of safety approval, SARMs are often illegally marketed as dietary supplements, available for consumers to buy online. In this study, a range of supplement products marketed as SARMs were purchased and analyzed using high resolution accurate mass - mass spectrometry to evaluate the accuracy of product claims and content labeling. This study found discrepancies ranging from a supplement in which no active ingredients were found, to supplements containing undeclared prohibited analytes. Where SARMs were detected, discrepancies were observed between the concentrations measured and those detailed on the product packaging. The outcome of this experiment highlights the high risk of such supplement products to consumers. The inaccurate product claims give rise to uncertainty over both the dose taken and the identity of any of these unapproved drugs. Even for supplements for which the product labeling is correct, the lack of complete toxicity data, especially for combinations of SARMs taken as stacks, means that the safety of these supplements is unknown.


Asunto(s)
Andrógenos/análisis , Suplementos Dietéticos/análisis , Drogas Ilícitas/análisis , Doping en los Deportes , Humanos , Detección de Abuso de Sustancias , Reino Unido
7.
Zootaxa ; 4743(1): zootaxa.4743.1.14, 2020 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-32230361

RESUMEN

Tuberocephalus tsengi (Tao, 1963) STAT. REV., an aphid species described from China, is reported feeding on Artemisia vulgaris in southern England. This species is here redescribed and distinguished from T. sasakii (Matsumura, 1917), with which it has previously been synonymised.


Asunto(s)
Áfidos , Artemisia , Animales , Reino Unido
8.
Regul Toxicol Pharmacol ; 113: 104624, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32126256

RESUMEN

An international expert working group representing 37 organisations (pharmaceutical/biotechnology companies, contract research organisations, academic institutions and regulatory bodies) collaborated in a data sharing exercise to evaluate the utility of two species within regulatory general toxicology studies. Anonymised data on 172 drug candidates (92 small molecules, 46 monoclonal antibodies, 15 recombinant proteins, 13 synthetic peptides and 6 antibody-drug conjugates) were submitted by 18 organisations. The use of one or two species across molecule types, the frequency for reduction to a single species within the package of general toxicology studies, and a comparison of target organ toxicities identified in each species in both short and longer-term studies were determined. Reduction to a single species for longer-term toxicity studies, as used for the development of biologicals (ICHS6(R1) guideline) was only applied for 8/133 drug candidates, but might have been possible for more, regardless of drug modality, as similar target organ toxicity profiles were identified in the short-term studies. However, definition and harmonisation around the criteria for similarity of toxicity profiles is needed to enable wider consideration of these principles. Analysis of a more robust dataset would be required to provide clear, evidence-based recommendations for expansion of these principles to small molecules or other modalities where two species toxicity testing is currently recommended.


Asunto(s)
Desarrollo de Medicamentos , Evaluación Preclínica de Medicamentos/efectos adversos , Pruebas de Toxicidad , Animales , Bases de Datos Factuales , Humanos , Medición de Riesgo
9.
Phys Chem Chem Phys ; 21(34): 18458-18466, 2019 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-31250870

RESUMEN

A compendium of pnictogen and chalcogen substituted boron heterocycles were assessed for their aromatic character by first principles density functional theory. Group-15 and Group-16 elements were placed at the ortho-, meta-, and para-positions of six-membered rings relative to boron to assess their impact on the aromaticity of the unsaturated heterocycles. Aromaticity was analyzed by a multidimensional approach using nuclear independent chemical shifts, gauge-including magnetically induced current, as well as natural bond orbital and natural resonance theory analyses. Based on these methods, we observe a general decline of aromaticity in heavier pnictaborines while the chalcogen analogues maintain relatively strong aromatic character. These general trends result from complementary π-π* natural bond order interactions that sustain resonance within the ring of each heterocycle establishing a pattern of cyclic delocalization. Consequently, natural resonance theory displays strong resonance, which is corroborated with the signed modulus of ring current, toroidal vortices of current maps, and elevated average induced current throughout the ring. The 1,3-configurations for pnictaborines and chalcogenaborines are generally more aromatic compared to the 1,2- and 1,4-isomers, which contain π-holes that limit diatropism within the heterocycles. However, an energetic trend favors the 1,2-heterocycles in both groups, with a few exceptions driven in large-part by π-donation of the lone pair on the heteroatom to the pz orbital on the adjacent boron resulting in stabilization. The importance of planarity for high aromaticity is demonstrated, especially in the pnictaborine isomers where pyramidalization at the pnictogen is favored, while bond regularity seems a less important criterion.

10.
Cochrane Database Syst Rev ; 7: CD011492, 2018 07 09.
Artículo en Inglés | MEDLINE | ID: mdl-29987845

RESUMEN

BACKGROUND: Brain radionecrosis (tissue death caused by radiation) can occur following high-dose radiotherapy to brain tissue and can have a significant impact on a person's quality of life (QoL) and function. The underlying pathophysiological mechanism remains unclear for this condition, which makes establishing effective treatments challenging. OBJECTIVES: To assess the effectiveness of interventions used for the treatment of brain radionecrosis in adults over 18 years old. SEARCH METHODS: In October 2017, we searched the Cochrane Register of Controlled Trials (CENTRAL), MEDLINE, Embase and the Cumulative Index to Nursing and Allied Health Literature (CINAHL) for eligible studies. We also searched unpublished data through Physicians Data Query, www.controlled-trials.com/rct, www.clinicaltrials.gov, and www.cancer.gov/clinicaltrials for ongoing trials and handsearched relevant conference material. SELECTION CRITERIA: We included randomised controlled trials (RCTs) of any intervention directed to treat brain radionecrosis in adults over 18 years old previously treated with radiation therapy to the brain. We anticipated a limited number of RCTs, so we also planned to include all comparative prospective intervention trials and quasi-randomised trials of interventions for brain radionecrosis in adults as long as these studies had a comparison group that reflects the standard of care (i.e. placebo or corticosteroids). Selection bias was likely to be an issue in all the included non-randomised studies therefore results are interpreted with caution. DATA COLLECTION AND ANALYSIS: Two review authors (CC, PB) independently extracted data from selected studies and completed a 'Risk of bias' assessment. For dichotomous outcomes, the odds ratio (OR) for the outcome of interest was reported. For continuous outcomes, treatment effect was reported as mean difference (MD) between treatment arms with 95% confidence intervals (CIs). MAIN RESULTS: Two RCTs and one prospective non-randomised study evaluating pharmacological interventions met the inclusion criteria for this review. As each study evaluated a different drug or intervention using different endpoints, a meta-analysis was not possible. There were no trials of non-pharmacological interventions that met the inclusion criteria.A very small randomised, double-blind, placebo-controlled trial of bevacizumab versus placebo reported that 100% (7/7) of participants on bevacizumab had reduction in brain oedema by at least 25% and reduction in post-gadolinium enhancement, whereas all those receiving placebo had clinical or radiological worsening or both. This was an encouraging finding but due to the small sample size we did not report a relative effect. The authors also failed to provide adequate details regarding the randomisation and blinding procedures Therefore, the certainty of this evidence is low and a larger RCT adhering to reporting standards is needed.An open-label RCT demonstrated a greater reduction in brain oedema (T2 hyperintensity) in the edaravone plus corticosteroid group than in the corticosteroid alone group (MD was 3.03 (95% CI 0.14 to 5.92; low-certainty evidence due to high risk of bias and imprecision); although the result approached borderline significance, there was no evidence of any important difference in the reduction in post-gadolinium enhancement between arms (MD = 0.47, 95% CI - 0.80 to 1.74; low-certainty evidence due to high risk of bias and imprecision).In the RCT of bevacizumab versus placebo, all seven participants receiving bevacizumab were reported to have neurological improvement, whereas five of seven participants on placebo had neurological worsening (very low-certainty evidence due to small sample size and concerns over validity of analyses). While no adverse events were noted with placebo, three severe adverse events were noted with bevacizumab, which included aspiration pneumonia, pulmonary embolus and superior sagittal sinus thrombosis. In the RCT of corticosteroids with or without edaravone, the participants who received the combination treatment were noted to have significantly greater clinical improvement than corticosteroids alone based on LENT/SOMA scale (OR = 2.51, 95% CI 1.26 to 5.01; low-certainty evidence due to open-label design). No differences in treatment toxicities were observed between arms.One included prospective non-randomised study of alpha-tocopherol (vitamin E) versus no active treatment was found but it did not include any radiological assessment. As only one included study was a double-blinded randomised controlled trial, the other studies were prone to selection and detection biases.None of the included studies reported quality of life outcomes or adequately reported details about corticosteroid requirements.A limited number of prospective studies were identified but subsequently excluded as these studies had a limited number of participants evaluating different pharmacological interventions using variable endpoints. AUTHORS' CONCLUSIONS: There is a lack of good certainty evidence to help quantify the risks and benefits of interventions for the treatment of brain radionecrosis after radiotherapy or radiosurgery. In an RCT of 14 patients, bevacizumab showed radiological response which was associated with minimal improvement in cognition or symptom severity. Although it was a randomised trial by design, the small sample size limits the quality of data. A trial of edaravone plus corticosteroids versus corticosteroids alone reported greater reduction in the surrounding oedema with combination treatment but no effect on the enhancing radionecrosis lesion. Due to the open-label design and wide confidence intervals in the results, the quality of this data was also low. There was no evidence to support any non-pharmacological interventions for the treatment of radionecrosis. Further prospective randomised studies of pharmacological and non-pharmacological interventions are needed to generate stronger evidence. Two ongoing RCTs, one evaluating bevacizumab and one evaluating hyperbaric oxygen therapy were identified.


Asunto(s)
Corticoesteroides/uso terapéutico , Antipirina/análogos & derivados , Bevacizumab/uso terapéutico , Encéfalo/efectos de la radiación , Traumatismos por Radiación/terapia , Adulto , Antipirina/uso terapéutico , Bevacizumab/efectos adversos , Encéfalo/diagnóstico por imagen , Edema Encefálico/diagnóstico por imagen , Edema Encefálico/tratamiento farmacológico , Edema Encefálico/etiología , Quimioterapia Combinada , Edaravona , Gadolinio , Humanos , Ensayos Clínicos Controlados no Aleatorios como Asunto , Traumatismos por Radiación/diagnóstico por imagen , Traumatismos por Radiación/etiología , Radiocirugia/efectos adversos , Radioterapia/efectos adversos , Ensayos Clínicos Controlados Aleatorios como Asunto
11.
J Clin Oncol ; 36(5): 483-491, 2018 02 10.
Artículo en Inglés | MEDLINE | ID: mdl-29272161

RESUMEN

An estimated 20% of patients with cancer will develop brain metastases. Approximately 200,000 individuals in the United States alone receive whole-brain radiotherapy (WBRT) each year to treat brain metastases. Historically, the prognosis of patients with brain metastases has been poor; however, with new therapies, this is changing. Because patients are living longer following the diagnosis and treatment of brain metastases, there has been rising concern about treatment-related toxicities associated with WBRT, including neurocognitive toxicity. In addition, recent clinical trials have raised questions about the use of WBRT. To better understand this rapidly changing landscape, this review outlines the treatment roles and toxicities of WBRT and alternative therapies for the management of brain metastases.


Asunto(s)
Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/secundario , Antineoplásicos/administración & dosificación , Neoplasias Encefálicas/terapia , Terapia Combinada , Irradiación Craneana/efectos adversos , Irradiación Craneana/métodos , Terapia por Estimulación Eléctrica/métodos , Humanos , Metastasectomía , Cuidados Paliativos , Radiocirugia , Radioterapia Adyuvante , Terapia Recuperativa
12.
Neurosurgery ; 79 Suppl 1: S73-S82, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27861327

RESUMEN

BACKGROUND: Although surgery followed by radiation effectively treats metastatic epidural compression, the ideal surgical approach should enable fast recovery and rapid institution of radiation and systemic therapy directed at the primary tumor. OBJECTIVE: To assess spinal laser interstitial thermotherapy (SLITT) as an alternative to surgery monitored in real time by thermal magnetic resonance (MR) images. METHODS: Patients referred for spinal metastasis without motor deficits underwent MR-guided SLITT, followed by stereotactic radiosurgery. Clinical and radiological data were gathered prospectively, according to routine practice. RESULTS: MR imaging-guided SLITT was performed on 19 patients with metastatic epidural compression. No procedures were discontinued because of technical difficulties, and no permanent neurological injuries occurred. The median follow-up duration was 28 weeks (range 10-64 weeks). Systemic therapy was not interrupted to perform the procedures. The mean preoperative visual analog scale scores of 4.72 (SD ± 0.67) decreased to 2.56 (SD ± 0.71, P = .043) at 1 month and remained improved from baseline at 3.25 (SD ± 0.75, P = .021) 3 months after the procedure. The preoperative mean EQ-5D index for quality of life was 0.67 (SD ± 0.07) and remained without significant change at 1 month 0.79 (SD ± 0.06, P = .317) and improved at 3 months 0.83 (SD ± 0.06, P = .04) after SLITT. Follow-up MR imaging after 2 months revealed significant decompression of the neural component in 16 patients. However, 3 patients showed progression at follow-up, 1 was treated with surgical decompression and stabilization and 2 were treated with repeated SLITT. CONCLUSION: MR-guided SLITT can be both a feasible and safe alternative to separation surgery in carefully selected cases of spinal metastatic tumor epidural compression. ABBREVIATIONS: cEBRT, conventional external beam radiation therapyESCC, epidural spinal cord compressionSLITT, spinal laser interstitial thermotherapySSRS, stereotactic spinal radiosurgeryVAS, visual analog scale.


Asunto(s)
Terapia por Láser/métodos , Compresión de la Médula Espinal/cirugía , Neoplasias de la Columna Vertebral/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Descompresión Quirúrgica/métodos , Femenino , Humanos , Hipertermia Inducida/métodos , Imagenología Tridimensional/métodos , Imagen por Resonancia Magnética Intervencional , Masculino , Persona de Mediana Edad , Calidad de Vida , Estudios Retrospectivos , Compresión de la Médula Espinal/etiología , Neoplasias de la Columna Vertebral/secundario , Técnicas Estereotáxicas
13.
Neurosurg Focus ; 41(4): E2, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27690655

RESUMEN

OBJECTIVE An emerging paradigm for treating patients with epidural spinal cord compression (ESCC) caused by metastatic tumors is surgical decompression and stabilization, followed by stereotactic radiosurgery. In the setting of rapid progressive disease, interruption or delay in return to systemic treatment can lead to a negative impact in overall survival. To overcome this limitation, the authors introduce the use of spinal laser interstitial thermotherapy (sLITT) in association with percutaneous spinal stabilization to facilitate a rapid return to oncological treatment. METHODS The authors retrospectively reviewed a consecutive series of patients with ESCC and spinal instability who were considered to be poor surgical candidates and instead were treated with sLITT and percutaneous spinal stabilization. Demographic data, Spine Instability Neoplastic Scale score, degree of epidural compression before and after the procedure, length of hospital stay, and time to return to oncological treatment were analyzed. RESULTS Eight patients were treated with thermal ablation and percutaneous spinal stabilization. The primary tumors included melanoma (n = 3), lung (n = 3), thyroid (n = 1), and renal cell carcinoma (n = 1). The median Karnofsky Performance Scale score before and after the procedure was 60, and the median hospital stay was 5 days (range 3-18 days). The median Spine Instability Neoplastic Scale score was 13 (range 12-16). The mean modified postoperative ESCC score (2.75 ± 0.37) was significantly lower than the preoperative score (4.5 ± 0.27) (Mann-Whitney test, p = 0.0044). The median time to return to oncological treatment was 5 days (range 3-10 days). CONCLUSIONS The authors present the first cohort of sLITT associated with a percutaneous spinal stabilization for the treatment of ESCC and spinal instability. This minimally invasive technique can allow a faster recovery without prejudice of adjuvant systemic treatment, with adequate local control and spinal stabilization.


Asunto(s)
Descompresión Quirúrgica/métodos , Inestabilidad de la Articulación/cirugía , Terapia por Láser/métodos , Compresión de la Médula Espinal/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Inestabilidad de la Articulación/diagnóstico por imagen , Inestabilidad de la Articulación/etiología , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Neoplasias/complicaciones , Radiocirugia/métodos , Estudios Retrospectivos , Compresión de la Médula Espinal/diagnóstico por imagen , Compresión de la Médula Espinal/etiología , Resultado del Tratamiento
15.
J Neurosurg Spine ; 23(4): 400-11, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26140398

RESUMEN

OBJECT: High-grade malignant spinal cord compression is commonly managed with a combination of surgery aimed at removing the epidural tumor, followed by spinal stereotactic radiosurgery (SSRS) aimed at local tumor control. The authors here introduce the use of spinal laser interstitial thermotherapy (SLITT) as an alternative to surgery prior to SSRS. METHODS: Patients with a high degree of epidural malignant compression due to radioresistant tumors were selected for study. Visual analog scale (VAS) scores for pain and quality of life were obtained before and within 30 and 60 days after treatment. A laser probe was percutaneously placed in the epidural space. Real-time thermal MRI was used to monitor tissue damage in the region of interest. All patients received postoperative SSRS. The maximum thickness of the epidural tumor was measured, and the degree of epidural spinal cord compression (ESCC) was scored in pre- and postprocedure MRI. RESULTS: In the 11 patients eligible for study, the mean VAS score for pain decreased from 6.18 in the preoperative period to 4.27 within 30 days and 2.8 within 60 days after the procedure. A similar VAS interrogating the percentage of quality of life demonstrated improvement from 60% preoperatively to 70% within both 30 and 60 days after treatment. Imaging follow-up 2 months after the procedure demonstrated a significant reduction in the mean thickness of the epidural tumor from 8.82 mm (95% CI 7.38-10.25) before treatment to 6.36 mm (95% CI 4.65-8.07) after SLITT and SSRS (p = 0.0001). The median preoperative ESCC Grade 2 was scored as 4, which was significantly higher than the score of 2 for Grade 1b (p = 0.04) on imaging follow-up 2 months after the procedure. CONCLUTIONS: The authors present the first report on an innovative minimally invasive alternative to surgery in the management of spinal metastasis. In their early experience, SLITT has provided local control with low morbidity and improvement in both pain and the quality of life of patients.


Asunto(s)
Hipertermia Inducida/instrumentación , Terapia por Láser/métodos , Imagen por Resonancia Magnética Intervencional , Compresión de la Médula Espinal/terapia , Neoplasias de la Columna Vertebral/terapia , Adulto , Anciano , Terapia Combinada , Femenino , Humanos , Masculino , Persona de Mediana Edad , Dimensión del Dolor , Calidad de Vida , Radiocirugia , Estudios Retrospectivos , Compresión de la Médula Espinal/etiología , Neoplasias de la Columna Vertebral/complicaciones , Resultado del Tratamiento
16.
J Pastoral Care Counsel ; 69(1): 40-5, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26162206

RESUMEN

This is a report of a short-term, pastoral counselling group conducted with Jewish internees in a high security prison in Israel. It was held as an adjunct to daily secular individual and group counselling and rehabilitation run by the Department of Social Work. Pastoral counselling employed spiritual and psychosocial methodologies to reduce anger, improve prisoner frustration tolerance, and develop a sense of self-efficacy and communal identity. It combined semi-didactic scriptural input with Pierre Janet's personality model, Fritz Perls' gestalt therapy, and analysis of the group process.


Asunto(s)
Terapia Cognitivo-Conductual/métodos , Terapia Gestalt/métodos , Cuidado Pastoral/métodos , Prisioneros/psicología , Psicoterapia de Grupo/métodos , Adulto , Humanos , Imágenes en Psicoterapia/métodos , Israel , Persona de Mediana Edad , Prisiones , Adulto Joven
17.
Nat Commun ; 5: 5154, 2014 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-25300366

RESUMEN

Magnetite (Fe3O4) is an important magnetic mineral to Earth scientists, as it carries the dominant magnetic signature in rocks, and the understanding of its magnetic recording fidelity provides a critical tool in the field of palaeomagnetism. However, reliable interpretation of the recording fidelity of Fe3O4 particles is greatly diminished over time by progressive oxidation to less magnetic iron oxides, such as maghemite (γ-Fe2O3), with consequent alteration of remanent magnetization potentially having important geological significance. Here we use the complementary techniques of environmental transmission electron microscopy and off-axis electron holography to induce and visualize the effects of oxidation on the magnetization of individual nanoscale Fe3O4 particles as they transform towards γ-Fe2O3. Magnetic induction maps demonstrate a change in both strength and direction of remanent magnetization within Fe3O4 particles in the size range dominant in rocks, confirming that oxidation can modify the original stored magnetic information.

18.
Regul Toxicol Pharmacol ; 70(1): 413-29, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25078890

RESUMEN

An international expert group which includes 30 organisations (pharmaceutical companies, contract research organisations, academic institutions and regulatory bodies) has shared data on the use of recovery animals in the assessment of pharmaceutical safety for early development. These data have been used as an evidence-base to make recommendations on the inclusion of recovery animals in toxicology studies to achieve scientific objectives, while reducing animal use. Recovery animals are used in pharmaceutical development to provide information on the potential for a toxic effect to translate into long-term human risk. They are included on toxicology studies to assess whether effects observed during dosing persist or reverse once treatment ends. The group devised a questionnaire to collect information on the use of recovery animals in general regulatory toxicology studies to support first-in-human studies. Questions focused on study design, the rationale behind inclusion or exclusion and the impact this had on internal and regulatory decisions. Data on 137 compounds (including 53 biologicals and 78 small molecules) from 259 studies showed wide variation in where, when and why recovery animals were included. An analysis of individual study and programme design shows that there are opportunities to reduce the use of recovery animals without impacting drug development.


Asunto(s)
Diseño de Fármacos , Evaluación Preclínica de Medicamentos/métodos , Modelos Animales , Toxicología/métodos , Animales , Humanos , Cooperación Internacional , Proyectos de Investigación , Encuestas y Cuestionarios , Factores de Tiempo
19.
Environ Sci Technol ; 45(7): 3075-81, 2011 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-21351802

RESUMEN

Fulvic acid (FA) from a tropical Australian billabong (lagoon) was isolated with XAD-8 resin and characterized using size exclusion chromatography, solid state cross-polarization magic angle spinning, 13C nuclear magnetic resonance spectroscopy, elemental analysis, and potentiometric acid-base titration. Physicochemical characteristics of the billabong FA were comparable with those of the Suwannee River Fulvic Acid (SRFA) standard. The greater negative charge density of the billabong FA suggested it contained protons that were more weakly bound than those of SRFA, with the potential for billabong water to complex less metal contaminants, such as uranium (U). This may subsequently influence the toxicity of metal contaminants to resident freshwater organisms. The complexation of U with dissolved organic carbon (DOC) (10 mg L(-1)) in billabong water was calculated using the HARPHRQ geochemical speciation model and also measured using flow field-flow fractionation combined with inductively coupled plasma mass-spectroscopy. Agreement between both methods was very good (within 4% as U-DOC). The results suggest that in billabong water at pH 6.0, containing an average DOC of 10 mg L(-1) and a U concentration of 90 µg L(-1), around 10% of U is complexed with DOC.


Asunto(s)
Benzopiranos/química , Carbono/química , Uranio/química , Contaminantes Radiactivos del Agua/química , Organismos Acuáticos/efectos de los fármacos , Agua Dulce/química , Concentración de Iones de Hidrógeno , Cinética , Modelos Químicos , Peso Molecular , Uranio/toxicidad , Contaminantes Radiactivos del Agua/toxicidad
20.
Lipids ; 45(1): 21-7, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20049582

RESUMEN

Rapid expansion of aquacultural production is placing increasing demand on fish oil supplies and intensified the search for alternative lipid sources. Many of the potential alternative sources contain low concentrations of long chain n-3 fatty acids and the conversion of dietary linolenic acid to longer chain highly unsaturated fatty acids is a relatively inefficient process in some species. A 6-week study was conducted to compare tissue fatty acid (FA) concentrations in hybrid striped bass fed either 18:3n-3 (alpha-linolenic acid; ALA) or 18:4n-3 (stearidonic acid; SDA). Hybrid striped bass were fed either a control diet containing fish oil, or diets containing ALA or SDA at three different levels (0.5, 1 and 2% of the diet). There were no significant differences in whole animal responses between fish fed ALA or SDA. Liver and muscle concentrations of ALA and SDA were responsive to dosages fed. However, only 22:6n-3 concentrations in muscle were significantly affected by dietary source of 18 carbon precursors. Muscle 22:6n-3 concentrations were significantly higher in fish fed SDA compared to fish fed ALA. Based on these data, it appears that feeding SDA can increase long chain n-3 fatty acid concentrations in fish muscle.


Asunto(s)
Fenómenos Fisiológicos Nutricionales de los Animales , Grasas Insaturadas en la Dieta/administración & dosificación , Ácidos Grasos Omega-3/metabolismo , Ácido alfa-Linolénico/metabolismo , Animales , Lubina , Ácidos Docosahexaenoicos/metabolismo , Ácidos Grasos/análisis , Músculos/química , Músculos/metabolismo
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