RESUMEN
INTRODUCTION: This document is a summary of the French intergroup guidelines regarding the management of esophageal cancer (EC) published in July 2022, available on the website of the French Society of Gastroenterology (SNFGE) (www.tncd.org). METHODS: This collaborative work was conducted under the auspices of several French medical and surgical societies involved in the management of EC. Recommendations were graded in three categories (A, B and C), according to the level of evidence found in the literature until April 2022. RESULTS: EC diagnosis and staging evaluation are mainly based on patient's general condition assessment, endoscopy plus biopsies, TAP CT-scan and 18F FDG-PET. Surgery alone is recommended for early-stage EC, while locally advanced disease (N+ and/or T3-4) is treated with perioperative chemotherapy (FLOT) or preoperative chemoradiation (CROSS regimen) followed by immunotherapy for adenocarcinoma. Preoperative chemoradiation (CROSS regimen) followed by immunotherapy or definitive chemoradiation with the possibility of organ preservation are the two options for squamous cell carcinoma. Salvage surgery is recommended for incomplete response or recurrence after definitive chemoradiation and should be performed in an expert center. Treatment for metastatic disease is based on systemic therapy including chemotherapy, immunotherapy or combined targeted therapy according to biomarkers testing such as HER2 status, MMR status and PD-L1 expression. CONCLUSION: These guidelines are intended to provide a personalised therapeutic strategy for daily clinical practice and are subject to ongoing optimization. Each individual case should be discussed by a multidisciplinary team.
Asunto(s)
Adenocarcinoma , Neoplasias Esofágicas , Humanos , Estudios de Seguimiento , Neoplasias Esofágicas/diagnóstico por imagen , Neoplasias Esofágicas/terapia , Terapia Combinada , Adenocarcinoma/diagnóstico por imagen , Adenocarcinoma/terapiaRESUMEN
In recent years the intestinal microbiome and its interaction with the brain has aroused a growing interest. The findings gained in the course of this research are of great relevance not only to basic scientists but also to clinicians, as studies suggest an association between an altered microbiome and various somatic (e.g. chronic inflammatory intestinal diseases, obesity and diabetes) as well as psychiatric diseases (e.g. anxiety disorders, depression). In addition to a direct influence of the microbiome on the brain and behavior, various mechanisms seem to be relevant, including altered energy intake from food, hormonal changes, probably increased intestinal permeability as well as inflammatory and immunological processes. Anorexia nervosa (AN) is the third most common chronic disease in adolescence and has the highest mortality rate among all mental disorders. In addition to extremely restrictive eating habits, weight loss and comorbid anxiety and depression symptoms, endocrine changes and an increased autoimmune and inflammatory response are characteristic. Since AN is particularly strongly linked to eating behavior and nutrition, research into the microbiome seems very promising, especially with respect to this disease. This article gives a first insight into the underlying processes that play a role in gut-brain interaction in the context of AN and summarizes the previous empirical findings on this topic. Finally, an outlook on future research and possible implications for the therapeutic practice and treatment of AN is given.
Asunto(s)
Anorexia Nerviosa , Microbioma Gastrointestinal , Microbiota , Adolescente , Encéfalo , Conducta Alimentaria , HumanosRESUMEN
In this work, a bioresorbable Mg-ZKQX6000 (Mg-6Zn-0.6Zr-0.4Ag-0.2Ca (wt%)) alloy was severely plastically deformed via equal channel angular pressing (ECAP) according to three unique hybrid routes at low temperatures (200 °C to 125 °C). The roles of ECAP processing on microstructure, and ensuing mechanical properties and corrosion rates, are assessed. Microstructurally, ECAP induces a complex plethora of features, especially variations in grain sizes and precipitates' sizes, distributions, and morphologies for individual cases. Mechanically, ECAP generally refined grain size, resulting in ultra-high strength levels of about 400 MPa in ultimate tensile strength for several cases; however, deformation via ECAP of precipitates induced embrittlement and low elongation to failure levels. Corrosion testing, conducted in simulated bodily fluid at bodily pH levels to mimic conditions in the human body, revealed consistent corrosion rates across several techniques (mass loss, hydrogen evolution, and electrochemical impedance spectroscopy (EIS)), showing that severe plastic deformation deteriorates corrosion resistance for this material. In-situ corrosion monitoring explained that corrosion accelerated after ECAP due to the creation of heterogeneous, anodic shear zones, which exhibited dense regions of refined grains and fine precipitates. Suggestions for future design and thermomechanical processing of Mg alloys for bioresorbable orthopedic implants are provided.
Asunto(s)
Aleaciones/química , Plásticos Biodegradables/química , Magnesio/química , Implantes Absorbibles , Corrosión , Espectroscopía Dieléctrica , Ensayo de MaterialesRESUMEN
Biodegradable magnesium alloys are suitable osteosynthesis materials. Despite the alloy composition, surface modifications appear to have an influence on the degradation process and biocompatibility. The aim of this study was to investigate the impact of hydrogenation and fluoridation of the surface in a mandibular osteotomy model. Standard-sized plates and screws were implanted in an osteotomy at the mandibular angle in nine miniature pigs. The plates and screws were harvested together with the adjacent tissues at 8 weeks after surgery and were investigated by micro-computed tomography and histological analysis. The bone healing of the osteotomy was undisturbed, independent of the surface properties. The adjacent bone tissue showed new bone formation at the implant surface; however, formation of some lacunae could be observed. The corrosion was between 9.8% and 11.6% (fluoridatedAsunto(s)
Magnesio
, Osteotomía Mandibular
, Aleaciones
, Animales
, Tornillos Óseos
, Ensayo de Materiales
, Porcinos
, Porcinos Enanos
, Microtomografía por Rayos X
RESUMEN
In MRI scans of patients with anorexia nervosa (AN), reductions in brain volume are often apparent. However, it is unknown whether such brain abnormalities are influenced by genetic determinants that partially overlap with those underlying AN. Here, we used a battery of methods (LD score regression, genetic risk scores, sign test, SNP effect concordance analysis, and Mendelian randomization) to investigate the genetic covariation between subcortical brain volumes and risk for AN based on summary measures retrieved from genome-wide association studies of regional brain volumes (ENIGMA consortium, n = 13,170) and genetic risk for AN (PGC-ED consortium, n = 14,477). Genetic correlations ranged from - 0.10 to 0.23 (all p > 0.05). There were some signs of an inverse concordance between greater thalamus volume and risk for AN (permuted p = 0.009, 95% CI: [0.005, 0.017]). A genetic variant in the vicinity of ZW10, a gene involved in cell division, and neurotransmitter and immune system relevant genes, in particular DRD2, was significantly associated with AN only after conditioning on its association with caudate volume (pFDR = 0.025). Another genetic variant linked to LRRC4C, important in axonal and synaptic development, reached significance after conditioning on hippocampal volume (pFDR = 0.021). In this comprehensive set of analyses and based on the largest available sample sizes to date, there was weak evidence for associations between risk for AN and risk for abnormal subcortical brain volumes at a global level (that is, common variant genetic architecture), but suggestive evidence for effects of single genetic markers. Highly powered multimodal brain- and disorder-related genome-wide studies are needed to further dissect the shared genetic influences on brain structure and risk for AN.
Asunto(s)
Anorexia Nerviosa/diagnóstico por imagen , Anorexia Nerviosa/genética , Encéfalo/diagnóstico por imagen , Estudio de Asociación del Genoma Completo/métodos , Análisis de la Aleatorización Mendeliana/métodos , Polimorfismo de Nucleótido Simple/genética , Encéfalo/fisiología , Estudios de Casos y Controles , Humanos , Desequilibrio de Ligamiento/genética , Imagen por Resonancia Magnética/métodos , Tamaño de los ÓrganosRESUMEN
BACKGROUND: Outcome of intermediate risk rectal cancer may be improved by the addition of oxaliplatin during 5-fluoruracil concomitant neoadjuvant chemoradiotherapy. The purpose of this study is to analyze the main clinical results of the ACCORD12 trial (NCT00227747) in rectal cancer after 5 years of follow-up. PATIENTS AND METHODS: Inclusion criteria were as follows: rectal adenocarcinoma accessible to digital examination staged T3-T4 Nx M0 (or T2 Nx distal anterior rectum). Two neoadjuvant chemoradiotherapy regimens were randomized: CAP45 (RT 45 Gy + capecitabine) and CAPOX50 (RT 50 Gy + capecitabine and oxaliplatin). Main end point was sterilization of the operative specimen. Acute and late toxicities were prospectively analyzed with dedicated questionnaires. RESULTS: Between November 2005 and July 2008, 598 patients were included in the trial. After a median follow-up of 60.2 months, there was no difference between treatment arms in multivariate analysis either for disease-free survival or overall survival (OS) [P = 0.9, hazard ratio (HR)=1.02; 95% confidence interval (CI), 0.76-1.36 and P = 0.3, HR = 0.87; 95% CI, 0.66-1.15, respectively]. There was also no difference of local control in univariate analysis (P = 0.7, HR = 0.92; 95% CI, 0.51-1.66). Late toxicities were acceptable with 1.6% G3 anal incontinence, and <1% G3 diarrhea, G3 rectal bleeding, G3 stenosis, G3-4 pain, G3 urinary incontinence, G3 urinary retention and G3 skeletal toxicity. There was a slight increase of erectile dysfunction over time with a 63% rate of erectile dysfunction at 5 years. There was no significant statistical difference for these toxicities between treatment arms. CONCLUSIONS: The CAPOX50 regimen did not improve local control, disease-free survival and overall survival in the ACCORD12 trial. Late toxicities did not differ between treatment arms.
Asunto(s)
Adenocarcinoma/tratamiento farmacológico , Adenocarcinoma/radioterapia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Capecitabina/uso terapéutico , Neoplasias del Recto/tratamiento farmacológico , Neoplasias del Recto/radioterapia , Adenocarcinoma/patología , Adulto , Anciano , Anciano de 80 o más Años , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Capecitabina/administración & dosificación , Capecitabina/efectos adversos , Quimioradioterapia Adyuvante/efectos adversos , Supervivencia sin Enfermedad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Terapia Neoadyuvante/efectos adversos , Compuestos Organoplatinos/administración & dosificación , Oxaliplatino , Neoplasias del Recto/patología , Tasa de SupervivenciaRESUMEN
BACKGROUND: In a phase III trial in patients with advanced, well-differentiated, progressive pancreatic neuroendocrine tumors, sunitinib 37.5 mg/day improved investigator-assessed progression-free survival (PFS) versus placebo (11.4 versus 5.5 months; HR, 0.42; P < 0.001). Here, we present PFS using retrospective blinded independent central review (BICR) and final median overall survival (OS), including an assessment highlighting the impact of patient crossover from placebo to sunitinib. PATIENTS AND METHODS: In this randomized, double-blind, placebo-controlled study, cross-sectional imaging from patients was evaluated retrospectively by blinded third-party radiologists using a two-reader, two-time-point lock, followed by a sequential locked-read, batch-mode paradigm. OS was summarized using the Kaplan-Meier method and Cox proportional hazards model. Crossover-adjusted OS effect was derived using rank-preserving structural failure time (RPSFT) analyses. RESULTS: Of 171 randomized patients (sunitinib, n = 86; placebo, n = 85), 160 (94%) had complete scan sets/time points. By BICR, median (95% confidence interval [CI]) PFS was 12.6 (11.1-20.6) months for sunitinib and 5.8 (3.8-7.2) months for placebo (HR, 0.32; 95% CI 0.18-0.55; P = 0.000015). Five years after study closure, median (95% CI) OS was 38.6 (25.6-56.4) months for sunitinib and 29.1 (16.4-36.8) months for placebo (HR, 0.73; 95% CI 0.50-1.06; P = 0.094), with 69% of placebo patients having crossed over to sunitinib. RPSFT analysis confirmed an OS benefit for sunitinib. CONCLUSIONS: BICR confirmed the doubling of PFS with sunitinib compared with placebo. Although the observed median OS improved by nearly 10 months, the effect estimate did not reach statistical significance, potentially due to crossover from placebo to sunitinib. TRIAL REGISTRATION NUMBER: NCT00428597.
Asunto(s)
Indoles/administración & dosificación , Tumores Neuroendocrinos/tratamiento farmacológico , Neoplasias Pancreáticas/tratamiento farmacológico , Pirroles/administración & dosificación , Antineoplásicos/administración & dosificación , Estudios Transversales , Supervivencia sin Enfermedad , Método Doble Ciego , Humanos , Estimación de Kaplan-Meier , Tumores Neuroendocrinos/diagnóstico por imagen , Neoplasias Pancreáticas/diagnóstico por imagen , Modelos de Riesgos Proporcionales , Sunitinib , Tasa de SupervivenciaRESUMEN
Gray matter (GM) and white matter (WM) volume loss occur in the brains of patients with acute anorexia nervosa (AN) and improve again upon weight restoration. Adolescence is an important time period for AN to begin. However, little is known about the differences between brain changes in adolescents vs adults. We used a meta-analysis and a qualitative review of all MRI studies regarding acute structural brain volume changes and their recovery in adolescents and adults with AN. 29 studies with 473 acute, 121 short-term weight-recovered and 255 long-term recovered patients with AN were included in the meta-analysis. In acute AN, GM and WM were reduced compared to healthy controls. Acute adolescent patients showed a significantly greater GM reduction than adults (-8.4 vs -3.1 %), the difference in WM (-4.0 vs -2.1 %) did not reach significance. Short-term weight-recovered patients showed a remaining GM deficit of 3.6 % and a non-significant WM reduction of 0.9 % with no age differences. Following 1.5-8 years of remission, GM and WM were no longer significantly reduced in adults (GM -0.4 %, WM -0.7 %); long-term studies for adolescents were scarce. The qualitative review showed that GM volume loss was correlated with cognitive deficits and three studies found GM regions, cerebellar deficits and WM to be predictive of outcome. GM and WM are strongly reduced in acute AN and even more pronounced in adolescence. Long-term recovery appears to be complete for adults while no conclusions can be drawn for adolescents, thus caution remains.
Asunto(s)
Anorexia Nerviosa/diagnóstico por imagen , Mapeo Encefálico , Encéfalo/diagnóstico por imagen , Neuroimagen , Adolescente , Adulto , Factores de Edad , Anorexia Nerviosa/patología , Humanos , Adulto JovenRESUMEN
BACKGROUND: Patterns of disease recurrence in patients with oesophageal cancer following treatment with neoadjuvant chemoradiotherapy and surgery (nCRTS) or surgery alone are poorly reported. An understanding of patterns of disease recurrence is important for subsequent treatment planning. METHODS: An analysis was undertaken of patterns of disease recurrence from a phase III multicentre randomized trial (FFCD9901) comparing nCRTS with surgery alone in patients with stage I and II oesophageal cancer. RESULTS: Some 170 patients undergoing surgical resection were included in the study. R0 resection rates were similar in the two groups: 94 per cent following nCRTS versus 92 per cent after surgery alone (P = 0·749). After a median follow-up of 94·2 months, recurrent disease was found in 39·4 per cent of the overall cohort (31 per cent after nCRTS versus 47 per cent following surgery alone; P = 0·030). Locoregional recurrence was diagnosed in 41 patients (17 versus 30 per cent respectively; P = 0·047) and distant metastatic recurrence in 47 (23 versus 31 per cent respectively; P = 0·244). Metastatic recurrence was more frequent in patients with adenocarcinoma than in those with squamous cell cancer (40 versus 23·1 per cent respectively; P = 0·032). ypT0 N0 category was associated with prolonged time to mixed locoregional and metastatic recurrence (P = 0·009), and time to locoregional (P = 0·044) and metastatic (P = 0·055) recurrence. In multivariable analysis, node-positive disease predicted both locoregional (P = 0·001) and metastatic (P < 0·001) recurrence. CONCLUSION: Locoregional disease control following nCRTS indicated a local field effect not related solely to completeness of resection. pN+ disease was strongly predictive of time to locoregional and metastatic disease recurrence.
Asunto(s)
Adenocarcinoma/terapia , Carcinoma de Células Escamosas/terapia , Quimioradioterapia Adyuvante , Neoplasias Esofágicas/terapia , Esofagectomía , Terapia Neoadyuvante , Recurrencia Local de Neoplasia/epidemiología , Adenocarcinoma/patología , Adulto , Anciano , Carcinoma de Células Escamosas/patología , Neoplasias Esofágicas/patología , Femenino , Estudios de Seguimiento , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Metástasis de la Neoplasia , Recurrencia Local de Neoplasia/patología , Modelos de Riesgos Proporcionales , Resultado del TratamientoRESUMEN
Biodegradable and biocompatible magnesium alloys appear to be very promising not only for temporary clinical application but also for developing deformable and degradable medical implants. This study analyzes the in vivo degradation behavior and the impact on the paranasal sinuses of the highly ductile Mg-2 wt%Nd alloy (MgNd2) in order to provide a basis for a satisfying stent system for the therapy of a chronic sinusitis. Moreover, in vitro tests were carried out on primary porcine nasal epithelial cells (PNEC). For the in vivo tests, cylindrical MgNd2 specimens were implanted into the sinus' mucosa of minipigs. During and after a total period of 180 days the long-term biodegradation and biocompatibility properties after direct contact with the physiological tissue were analyzed. Biodegradation was investigated by measuring the mass and volume losses of the MgNd2 specimens as well as by performing element analyses to obtain information about the degradation layer. The influence on the surrounding tissue of paranasal sinuses was evaluated by endoscopic and histopathological examinations of the mucosa. Here, only a locally unspecific chronic infection was found. The degradation rate showed a maximum after 45 days postsurgery and was determined to decrease subsequently. In vitro experiments using PNEC showed adequate biocompatibility of MgNd2. This study demonstrates a good in vivo biocompatibility for MgNd2 in the system of paranasal sinuses and underlines the promising properties of alloy MgNd2 for biodegradable nasal stent applications.
Asunto(s)
Aleaciones/farmacología , Ensayo de Materiales/métodos , Mucosa Nasal/efectos de los fármacos , Aleaciones/efectos adversos , Animales , Materiales Biocompatibles/efectos adversos , Materiales Biocompatibles/farmacología , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Corrosión , Endoscopía , Seno Frontal/efectos de los fármacos , Seno Frontal/metabolismo , Seno Frontal/patología , Seno Frontal/ultraestructura , Inflamación/inducido químicamente , Inflamación/metabolismo , Mucosa Nasal/citología , Mucosa Nasal/fisiología , Mucosa Nasal/ultraestructura , Porcinos , Porcinos EnanosRESUMEN
The frontal sinus recess consists of anatomically narrow passages that are prone to stenosis in endonasal frontal sinus surgery for chronic sinus disease. Over the past 100 years, diverse frontal sinus stents have been developed and evaluated in clinical and animal studies. However, superinfection, formation of granulations tissue, stent dislocation and late stenosis of the duct have remained challenges and subject of debate in the literature. Currently developed biodegradable materials, including rare earth-containing magnesium alloys are promising candidates for application as temporary implant materials. The Mg 2 % wt Nd alloy (MgNd2) was used to design a nasal stent that fit the porcine anatomy. In the current study, we evaluate biocompatibility, biodegradation and functionality of a frontal sinus stent in 16 minipigs over 6 months. Intraoperative endoscopy revealed free stent lumen in all cases. Blood examination and clinical examinations indicated no systematic or local inflammation signs. The histopathology and elements analysis showed a very good biocompatibility. The µ-computed tomography-based volumetric analysis showed substantial stent degradation within 6 months. Our MgNd2 based stent appears to be a promising, solid basis for the development of a frontal sinus stent for clinical use.
Asunto(s)
Implantes Absorbibles , Aleaciones , Seno Frontal/cirugía , Magnesio , Stents , Animales , Seno Frontal/diagnóstico por imagen , Modelos Animales , Porcinos , Porcinos EnanosRESUMEN
Magnesium alloys are currently being investigated for use as resorbable biomaterials. Various applications for magnesium based implant materials have already been presented. Currently, stents and structures that sustain diseased or narrowed vessels seem to be the most promising areas. This study focuses on the use of a magnesium fluoride (MgF2 ) coated magnesium neodymium based alloy (MgNd2 ) and its use as a postsurgery stent material to avoid proliferation in the sinus region. Simple cylindrical shaped specimens were sown to the sinus' mucosa of pigs and left in place for different periods of time to investigate the long-term corrosion resistance of the alloy and its coating during direct contact with physiological tissue. Investigations made within this study explicitly focused on the corrosive behavior of the alloy in the region of a physiological sinus. Thus, losses in mass and volume, and element analyses were considered to obtain information about the specimens' corrosion performance over time. Furthermore, micrographs support the alloy specific corrosion type analyses which focus on grain boundary effects. This study demonstrates the general in vivo applicability of fluoride coated MgNd2 . The progress of corrosion was determined to be adequate and homogeneous over a total period of 180 days.
Asunto(s)
Aleaciones , Membrana Mucosa/efectos de los fármacos , Animales , PorcinosRESUMEN
BACKGROUND: This trial evaluated the feasibility and efficacy of combined sorafenib and irinotecan (NEXIRI) as second- or later-line treatment of patients with KRAS-mutated metastatic colorectal cancer (mCRC), who had progressed after irinotecan-based chemotherapy. METHODS: In Phase I, in a 3+3 dose escalation schedule, patients received irinotecan (125, 150 or 180 mg m(-2) every 2 weeks), in combination with 400 mg sorafenib b.d. The primary end point was the maximum-tolerated dose of irinotecan. In Phase II, the primary end point was disease control rate (DCR). Secondary end points were progression-free survival (PFS), overall survival (OS) and toxicity. RESULTS: Phase I included 10 patients (median age 63 (49-73)); no dose-limiting toxicity was seen. In Phase II, 54 patients (median age 60 (43-80) years) received irinotecan 180 mg m(-)(2) every 2 weeks with sorafenib 400 mg b.d. Nine patients (17%) remained on full-dose sorafenib. The DCR was 64.9% (95% CI, 51-77). Median PFS and OS were 3.7 (95% CI, 3.2-4.7) and 8.0 (95% CI, 4.8-9.7) months, respectively. Toxicities included Grade 3 diarrhoea (37%), neutropenia (18%), hand-foot syndrome (13%) and Grade 4 neutropenia (17%). CONCLUSION: The NEXIRI regimen showed promising activity as second- or later-line treatment in this heavily pretreated mCRC population (ClinicalTrials.gov NCT00989469).
Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias Colorrectales/tratamiento farmacológico , Mutación , Proteínas Proto-Oncogénicas/genética , Proteínas ras/genética , Adulto , Anciano , Anciano de 80 o más Años , Camptotecina/administración & dosificación , Camptotecina/análogos & derivados , Neoplasias Colorrectales/genética , Progresión de la Enfermedad , Supervivencia sin Enfermedad , Femenino , Humanos , Irinotecán , Masculino , Persona de Mediana Edad , Niacinamida/administración & dosificación , Niacinamida/análogos & derivados , Compuestos de Fenilurea/administración & dosificación , Proteínas Proto-Oncogénicas p21(ras) , SorafenibRESUMEN
The functions of some bone proteins, as osteopontin (OPN) and osteocalcin (OC), have been discovered by the latest studies. This fact suggests the possibility of their immunodetection to characterize peri-implant osteogenesis and implant impact on it. Cylindrical pins of Mg alloys (MgCa0.8, LAE442, ZEK100, LANd442) and titanium alloy (TiAl6V4) were implanted into the tibial medullae of 46 rabbits. Each group was divided regarding to implant duration (3 and 6 months). Bone samples adjacent to the implants were decalcified and treated with routine histological and immunohistochemical protocols using OC and OPN-antibodies. OC was detected in matrix of compact bone, but very rarely in osteoid and bone cells. OPN was detected intracellularly and in osteoid. After 3 months, the highest level of both markers was found in titanium group, followed by LAE442-group. In contrast to LAE442 and TiAl6V4, the other Mg alloys showed increasing levels of OC after 6 months. Lower levels of OP and OC compared to the control group are related to the continuous implant degradation and instability of bone-implant interface in early post-surgical period. Reduced marker's expression in LAE442 and TiAl6V4 groups after 6 months may indicate stabilization of bone-implant interface and completion of peri-implant neo-osteogenesis. Declining characters of OC and OPN expression over the implantation time, as well as their lowest levels in late post-surgical term, suggest a more appropriate biocompatibility of LAE442, which therefore seems to be the most preferable of the tested materials for the use in orthopaedic applications.
Asunto(s)
Huesos/citología , Huesos/efectos de los fármacos , Implantes Experimentales , Magnesio/farmacología , Osteocalcina/metabolismo , Osteogénesis/efectos de los fármacos , Osteopontina/metabolismo , Animales , Femenino , Inmunohistoquímica , Implantación de Prótesis , ConejosRESUMEN
Owing to their mechanical properties, metallic materials present a promising solution in the field of resorbable implants. The magnesium metabolism in humans differs depending on its introduction. The natural, oral administration of magnesium via, for example, food, essentially leads to an intracellular enrichment of Mg(2+) . In contrast, introducing magnesium-rich substances or implants into the tissue results in a different decomposition behavior. Here, exposing magnesium to artificial body electrolytes resulted in the formation of the following products: magnesium hydroxide, magnesium oxide, and magnesium chloride, as well as calcium and magnesium apatites. Moreover, it can be assumed that Mg(2+) , OH(-) ions, and gaseous hydrogen are also present and result from the reaction for magnesium in an aqueous environment. With the aid of physiological metabolic processes, the organism succeeds in either excreting the above mentioned products or integrating them into the natural metabolic process. Only a burst release of these products is to be considered a problem. A multitude of general tissue effects and responses from the Mg's degradation products is considered within this review, which is not targeting specific implant classes. Furthermore, common alloying elements of magnesium and their hazardous potential in vivo are taken into account.
Asunto(s)
Magnesio/farmacología , Metabolismo/efectos de los fármacos , Especificidad de Órganos/efectos de los fármacos , Aleaciones/farmacología , Humanos , Prótesis e ImplantesRESUMEN
BACKGROUND: Sorafenib is an oral anticancer agent targeting Ras-dependent signaling and angiogenic pathways. A phase I trial demonstrated that the combination of gemcitabine and sorafenib was well tolerated and had activity in advanced pancreatic cancer (APC) patients. The BAYPAN study was a multicentric, placebo-controlled, double-blind, randomized phase III trial comparing gemcitabine/sorafenib and gemcitabine/placebo in the treatment of APC. PATIENTS AND METHODS: The patient eligibility criteria were locally advanced or metastatic pancreatic adenocarcinoma, no prior therapy for advanced disease and a performance status of zero to two. The primary end point was progression-free survival (PFS). The patients received gemcitabine 1000 mg/m(2) i.v., weekly seven times followed by 1 rest week, then weekly three times every 4 weeks plus sorafenib 200 mg or placebo, two tablets p.o., twice daily continuously. RESULTS: Between December 2006 and September 2009, 104 patients were enrolled on the study (52 pts in each arm) and 102 patients were treated. The median and the 6-month PFS were 5.7 months and 48% for gemcitabine/placebo and 3.8 months and 33% for gemcitabine/sorafenib (P = 0.902, stratified log-rank test), respectively. The median overall survivals were 9.2 and 8 months, respectively (P = 0.231, log-rank test). The overall response rates were similar (19 and 23%, respectively). CONCLUSION: The addition of sorafenib to gemcitabine does not improve PFS in APC patients.
Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Desoxicitidina/análogos & derivados , Niacinamida/análogos & derivados , Neoplasias Pancreáticas/tratamiento farmacológico , Compuestos de Fenilurea/uso terapéutico , Adulto , Anciano , Anciano de 80 o más Años , Antimetabolitos Antineoplásicos/administración & dosificación , Antimetabolitos Antineoplásicos/efectos adversos , Antimetabolitos Antineoplásicos/uso terapéutico , Antineoplásicos/administración & dosificación , Antineoplásicos/efectos adversos , Antineoplásicos/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Desoxicitidina/administración & dosificación , Desoxicitidina/efectos adversos , Desoxicitidina/uso terapéutico , Supervivencia sin Enfermedad , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Niacinamida/administración & dosificación , Niacinamida/efectos adversos , Niacinamida/uso terapéutico , Compuestos de Fenilurea/administración & dosificación , Compuestos de Fenilurea/efectos adversos , Placebos , Inhibidores de Proteínas Quinasas/administración & dosificación , Inhibidores de Proteínas Quinasas/efectos adversos , Inhibidores de Proteínas Quinasas/uso terapéutico , Ribonucleótido Reductasas/antagonistas & inhibidores , Sorafenib , GemcitabinaRESUMEN
The aim of this study is to investigate and demonstrate the mechanical and corrosive characteristics of the neodymium-containing magnesium alloy MgNd2 (Nd2), which can be used as a resorbable implant material, especially in the field of stenting applications. To determine the mechanical characteristics of Nd2, tensile and compression tests were initially carried out in the hot extruded state. Here a unique elongation ratio (~30%) of the alloy could be observed. Subsequent T5 and T6 heat treatments were arranged to reveal their effect on the alloy's strengths and elongation values. The general degradation behaviour of Nd2 in a 0.9% NaCl solution was investigated by means of polarization curves and hydrogen evolution. In addition to this, by using various in vivo parameters, a corrosion environment was established to determine the alloy's degradation in vitro. Here, the mass loss per day in (MgF(2) and Bioglass)-coated and uncoated states and the corresponding maximum forces resulting from subsequent three-point bending tests revealed slow and steady corrosion behaviour. The cell viability and proliferation tests carried out on L-929 and MSC-P5 cells also showed good results. The mechanical and corrosive characteristics determined, as well as the in vitro test results obtained within the scope of this study, led to the development and successful in vivo testing of an MgF(2)-coated Nd2 mucosa stent which was introduced as an appropriate resorbable application.