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The Bio Economic Seaweed Model (BESeM) is a model designed for modelling tropical seaweed cultivation. BESeM can simulate the common tropical seaweed cultivation system with multiple harvests per year, clonal reproduction and labour intensive harvesting and replanting activities. Biomass growth is modelled as a sigmoid, with growth being initially exponentially and eventually flattening off towards a maximum weight per plant or per square meter (w f,max ). To estimate the latter, longer duration experiments than normal are needed - in the order of 100 days rather than 45 days. Drying (on platforms on the beach) is simulated as well as increase in harvested chemical concentration over time since planting, for harvested chemicals such as agar extracted from Gracilaria or carrageenan extracted from Kappaphycus or Euchema. BESeM has a limited number of parameters which makes it easily amenable to new sites and species. An experiment is presented for a site in Indonesia in which Gracilaria was monitored for 120 days in 6 nearby sites and from which BESeM model parameters were estimated. A simulation example is presented which illustrates how BESeM can be used to find the optimum combination of replanting weight and harvest cycle length (in days) for maximising gross and net farm income. Supplementary Information: The online version contains supplementary material available at 10.1007/s10811-022-02799-8.
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BACKGROUND & AIMS: A low muscle mass before start of treatment and loss of muscle mass during chemotherapy is related to adverse outcomes in patients with cancer. In this randomized controlled trial, the effect of nutritional counseling on change in muscle mass and treatment outcome in patients with metastatic colorectal cancer during first-line chemotherapy was studied. METHODS: Patients scheduled for first-line chemotherapy (n = 107) were randomly assigned to individualized nutritional counseling by a dietitian (NC) or usual care (UC). NC was aimed at sufficient protein- and energy intake, supported by oral supplements or enteral feeding if indicated. Furthermore, physical activity was encouraged. Outcomes were assessed at baseline (T0) and the time of the first (T1) and second (T2) regular follow-up computed tomography scans. The proportion of patients with a clinically relevant decrease in skeletal muscle area of ≥6.0 cm2, measured by computed tomography, was the primary outcome. Secondary outcomes included body weight, quality of life, treatment toxicity and progression free and overall survival. RESULTS: A total of 107 patients were enrolled (mean age, 65 years (SD, 11 years), 63% male). Mean change in skeletal muscle area from T0 till T1 was -2.5 (SD, 9.5) cm2, with no difference between NC versus UC (p = 0.891). The proportion of patients with a clinically relevant decrease in skeletal muscle area of ≥6.0 cm2 did not differ (NC 30% versus UC 31%, p = 0.467). NC compared with UC had a significant positive effect on body weight (B coefficient 1.7, p = 0.045), progression free survival (p = 0.039) and overall survival (p = 0.046). CONCLUSIONS: NC of patients undergoing chemotherapy for metastatic colorectal cancer had no effect on muscle mass. However, we found that NC may increase body weight and improve progression free survival and overall survival compared to UC in this group of patients. These findings need further evaluation in future clinical trials. CLINICAL TRIAL INFORMATION: ClinicalTrials.gov NCT01998152; Netherlands Trial Register NTR4223.
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Antineoplásicos/uso terapéutico , Composición Corporal , Neoplasias Colorrectales/tratamiento farmacológico , Consejo , Músculo Esquelético/fisiopatología , Apoyo Nutricional , Sarcopenia/terapia , Anciano , Antineoplásicos/efectos adversos , Neoplasias Colorrectales/mortalidad , Neoplasias Colorrectales/patología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Músculo Esquelético/diagnóstico por imagen , Metástasis de la Neoplasia , Países Bajos , Supervivencia sin Progresión , Sarcopenia/diagnóstico , Sarcopenia/mortalidad , Sarcopenia/fisiopatología , Método Simple Ciego , Factores de Tiempo , Tomografía Computarizada por Rayos X , Aumento de PesoRESUMEN
BACKGROUND/OBJECTIVES: Muscle mass is a key determinant of nutritional status and associated with outcomes in several patient groups. Computed tomography (CT) analysis is increasingly used to assess skeletal muscle area (SMA), skeletal muscle index (SMI) and muscle radiation attenuation (MRA). However, interpretation of these muscle parameters is difficult since values in a healthy population are lacking. The aim of this study was to provide sex specific percentiles for SMA, SMA and MRA in a healthy Caucasian population and to examine the association with age and BMI in order to define age- and BMI specific percentiles. SUBJECTS/METHODS: In this retrospective cross-sectional study CT scans of potential kidney donors were used to assess SMA, SMI and MRA at the level of the third lumbar vertebra. Sex specific distributions were described and, based on the association between age/BMI and muscle parameters, age, and BMI specific predicted percentiles were computed. The 5th percentile was considered as cut-off. RESULTS: CT scans of 420 Individuals were included (age range 20-82 years and BMI range 17.5-40.7 kg/m2). Sex specific cut-offs of SMA, SMI and MRA were 134.0 cm2, 41.6 cm2/m2 and 29.3 HU in men and 89.2 cm2, 32.0 cm2/m2 and 22.0 HU in women, respectively. Correlations were negative between age and all three muscle parameters, positive between BMI and SMA/SMI and negative between BMI and MRA, resulting in age- and BMI specific percentiles. CONCLUSIONS: This study provides sex specific percentiles for SMA, SMI, and MRA. In addition, age- and BMI specific percentiles have been established.
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Músculo Esquelético/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Adulto , Anciano , Anciano de 80 o más Años , Envejecimiento , Índice de Masa Corporal , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Músculo Esquelético/anatomía & histología , Músculo Esquelético/fisiología , Países Bajos , Estado Nutricional , Valores de Referencia , Estudios Retrospectivos , Factores Sexuales , Población BlancaAsunto(s)
Clima , Productos Agrícolas/crecimiento & desarrollo , Brasil , Calor , Dinámicas no Lineales , Estados UnidosRESUMEN
The role of Protein Kinase Inhibitors (PKI) in the treatment of various types of cancer is increasingly prominent. Their clinical application is accompanied by the development of side effects, among which patient-reported taste alterations. These alterations are missed frequently, but impair nutritional intake, are associated with weight loss and often result in significant morbidity, especially in the context of chronic administration. Accurate reporting of taste alterations is hampered by lack of modules for symptom objectification and inadequate understanding on the underlying mechanisms. In this review we initially describe the physiology of taste and smell and the mechanism of action of PKIs. We proceed to summarize taste related side effects as reported in major clinical trials and describe possible causal factors. Lastly, an in-depth analysis is given on potential molecular pathways responsible for the PKI-induced taste alterations. Objectification of patient-reported symptoms and universal reporting, along with a better understanding of the underlying mechanisms, will lead to early recognition and optimized treatment, ultimately improving patient adherence and quality of life.
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Antineoplásicos/efectos adversos , Encéfalo/efectos de los fármacos , Neoplasias/tratamiento farmacológico , Inhibidores de Proteínas Quinasas/efectos adversos , Trastornos del Gusto/inducido químicamente , Percepción del Gusto/efectos de los fármacos , Gusto/efectos de los fármacos , Encéfalo/metabolismo , Encéfalo/fisiopatología , Humanos , Terapia Molecular Dirigida , Neoplasias/enzimología , Neoplasias/patología , Receptores Acoplados a Proteínas G/efectos de los fármacos , Receptores Acoplados a Proteínas G/metabolismo , Factores de Riesgo , Transducción de Señal/efectos de los fármacos , Olfato/efectos de los fármacos , Trastornos del Gusto/metabolismo , Trastornos del Gusto/fisiopatología , Trastornos del Gusto/psicología , TerapéuticaRESUMEN
The effect of nimodipine was studied on EEG power density spectra as well as on 31P-NMR spectra of the brain before, during and after four-vessel occlusion (FVO) in the restrained conscious rat. EEG-spectral analysis: eight rats were submitted to 5 min FVO and four of them received nimodipine (1 mg/kg orally) 75 min before FVO. In the nimodipine-treated rats the post-ischemic overshoot of the EEG power density was significantly lower for the theta, alpha and beta band activity. 31P-NMR spectroscopy: the relative concentrations of phosphocreatine (PCr), ATP and Pi as well as intracellular pH were measured at different intervals after 10 min FVO (n = 10). All values normalised within 15-30 min after restoration of cerebral blood flow without significant differences between nimodipine-treated and control rats. It is concluded that pretreatment with nimodipine has a decreasing effect on the overshoot in EEG power density after transient incomplete forebrain ischemia. This effect was not correlated to significant changes in cerebral 'energy state', as measured by 31P-NMR spectroscopy.
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Isquemia Encefálica/fisiopatología , Electroencefalografía , Ácidos Nicotínicos/farmacología , Animales , Espectroscopía de Resonancia Magnética , Masculino , Nimodipina , Ratas , Ratas Endogámicas , Factores de TiempoRESUMEN
In the treatment of craniosynostosis several methods have been proposed to prevent craniectomies from early reclosure. New bone is formed at the edge of the craniectomy, but particularly at the outer surface of the dura. The author has developed a method to separate the edges from each other and to stop osteogenesis inside the craniectomy. The outer layer of the dura is dissected free from the inner layer folded over the edge of the groove and sutured to the outer periosteum. The operative technique and the results in 40 patients with a follow up of 17 years are described.
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Craneosinostosis/cirugía , Niño , Preescolar , Duramadre/cirugía , Fascia Lata/trasplante , Estudios de Seguimiento , Humanos , Lactante , Métodos , Periostio/cirugía , Técnicas de Sutura , Trasplante Autólogo , Cicatrización de HeridasRESUMEN
Acute subdural hematoma, local cerebral laceration and severe brain edema must be diagnosed at the earliest possible stage preferably by angiography and must be treated promptly by craniectomy of an adequate size in order to cope with all the blood clot, the lacerated brain tissue and the swollen brain.
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Hematoma Subdural/cirugía , Enfermedad Aguda , Adolescente , Adulto , Anciano , Femenino , Hematoma Subdural/diagnóstico , Humanos , Masculino , Métodos , Persona de Mediana EdadRESUMEN
A brain tumor in a 4-year-old child is described. The neoplasm was partly cystic and showed an a-typical multi-differentiated aspect. Microscopically the neoplasm had a clear-cut 'malignant' morphology. This tumor represents possibly a partly maturated primitive neuroectodermal brain tumor. The term PNET is briefly discussed in relation to the clinical implications.
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Neoplasias Encefálicas/patología , Neoplasias de Células Germinales y Embrionarias/patología , Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/cirugía , Preescolar , Humanos , Masculino , Recurrencia Local de Neoplasia , Neoplasias de Células Germinales y Embrionarias/diagnóstico por imagen , Neoplasias de Células Germinales y Embrionarias/cirugía , Radiografía , Reoperación , Terminología como AsuntoRESUMEN
This paper describes the results obtained in the treatment of posttraumatic carotid-cavernous fistulas in 7 patients. The method used consisted of closure of the fistula with the aid of a detachable balloon. The advantage of this method over most others is that it closes the fistula but leaves carotid patency intact. In addition to the results, some technical aspects of this method are discussed.
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Enfermedades de las Arterias Carótidas/cirugía , Fístula/cirugía , Adolescente , Adulto , Angiografía , Arterias Carótidas/diagnóstico por imagen , Arterias Carótidas/cirugía , Enfermedades de las Arterias Carótidas/diagnóstico por imagen , Seno Cavernoso/diagnóstico por imagen , Seno Cavernoso/cirugía , Constricción , Femenino , Fístula/diagnóstico por imagen , Humanos , Masculino , Persona de Mediana EdadRESUMEN
Fluorescent In Situ Hybridisation (FISH) was used to monitor the presence of filamentous microorganisms in industrial wastewater treatment plants (WWTPs). Monitoring with a restricted set of FISH probes in WWTPs from potato industry showed growth and decline of Thiothrix populations that could be linked to operational procedures. In a follow up project new FISH probes were developed for filamentous bacteria in industrial WWTPs and 70 WWTPs were analysed for presence of these filaments. Several newly described species of filamentous bacteria appear to be common and dominant in industrial WWTPs. Monitoring of a WWTP from textile industry showed growth and decline of one of these organisms when operational conditions in the plant were varied. The present paper demonstrates that bulking sludge in industrial wastewater treatment plants can effectively be monitored using a combination of standard chemical analyses and the FISH technique.
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Residuos Industriales , Proteobacteria/fisiología , Eliminación de Residuos Líquidos , Hibridación Fluorescente in Situ , Dinámica Poblacional , Industria TextilRESUMEN
The most frequent symptom of an arteriovenous fistula is a bruit, often audible to the patient himself. The indication for treatment of such fistulae depends on the severity of the symptoms and on the risks of excessive strain on the heart, circulatory insufficiency and haemorrhages. The treatment of choice of direct communications between arteries and veins is detachable balloon occlusion by a transvascular technique rather than surgery. The method is described and three personal cases are reported. There were no complications, and the hospital stay was limited to 2-3 days.
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Fístula Arteriovenosa/complicaciones , Acúfeno/etiología , Adolescente , Fístula Arteriovenosa/diagnóstico por imagen , Fístula Arteriovenosa/terapia , Arteria Carótida Externa , Niño , Preescolar , Embolización Terapéutica , Femenino , Humanos , Venas Yugulares , Masculino , Radiografía , Arteria VertebralRESUMEN
In the treatment of craniosynostosis methods have been proposed to prevent craniectomies from early reclosure. New bone is formed at the edge of the craniectomy but particularly at the outer surface of the dura. The author has developed a method to separate the edges from each other and to stop osteogenesis inside the craniectomy. The outer layer of the dura is dissected free from the inner layer, folded over the edge of the groove and sutured to the outer periosteum. The operative technique and the results in 40 patients with a follow up of up to 17 years are described.
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Craneosinostosis/cirugía , Duramadre/cirugía , Fascia Lata/trasplante , Fascia/trasplante , Niño , Preescolar , Craneosinostosis/diagnóstico por imagen , Estudios de Seguimiento , Humanos , Lactante , Recién Nacido , Métodos , Osteogénesis , Polietilenos/efectos adversos , Complicaciones Posoperatorias , Seudotumor Cerebral/etiología , Radiografía , Cráneo/diagnóstico por imagen , Trasplante AutólogoRESUMEN
The author discusses the epidemiology, the diagnosis, the clinical and morphological aspects of cerebral vasospasm from his personal experience and a study of the literature. Prediction and diagnosis of vasospasm is possible by evaluation of the amount of blood on CT scan, measuring fibrin breakdown products in the CSF and the findings of early EEG and Transcranial Doppler Sonography. CBF measurement is helpful in following the process of ischemia and deciding the right moment for operation. Early surgery on cerebral aneurysms is advocated in order to prevent rebleeding and for early removal of blood clot from the basal cisterns. If vasospasm and ischemia do develop, energetic treatment with hypervolemia and induced hypertension can be started without fear of rebleeding. Prophylactic intravenous administration of Nimodipine is thought to be of real value. Since the introduction of early surgery by the author 80 patients have been operated within 3 days after S.A.H. The mortality was 11% and the morbidity 7.5%. Management mortality and morbidity for the total group of 209 patients with S.A.H. treated either medically or surgically were 23.5% and 6% respectively. If one excludes the 18 patients that died within 24 hours the mortality was 15.6%.
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Isquemia Encefálica/etiología , Aneurisma Intracraneal/complicaciones , Ataque Isquémico Transitorio/etiología , Hemorragia Subaracnoidea/etiología , Isquemia Encefálica/fisiopatología , Isquemia Encefálica/terapia , Bloqueadores de los Canales de Calcio/uso terapéutico , Angiografía Cerebral , Electroencefalografía , Productos de Degradación de Fibrina-Fibrinógeno/líquido cefalorraquídeo , Humanos , Aneurisma Intracraneal/cirugía , Ataque Isquémico Transitorio/terapia , Ácidos Nicotínicos/uso terapéutico , Nimodipina , Rotura Espontánea , Hemorragia Subaracnoidea/complicaciones , Tomografía Computarizada por Rayos X , UltrasonografíaRESUMEN
The authors have operated a consecutive series of 80 acoustic neurinomas. They were able to preserve the facial nerve in 53 patients. In thirteen cases an intracranial reconstruction of the nerve was performed : six times by direct anastomosis, in seven cases by grafting the nerve with the sural nerve. Details of the operative technique and the functional results are reported.