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1.
EClinicalMedicine ; 72: 102624, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38737002

RESUMEN

Background: Previous studies have indicated that glucagon-like peptide-1 (GLP-1) receptor agonists (GLP-1RAs) may enhance bone formation and have neutral or beneficial effects on fracture risk. We evaluated the effect of the GLP-1RA semaglutide on the bone formation marker Procollagen type I N-terminal propeptide (PINP) in adults with increased fracture risk. Methods: This randomised, placebo-controlled, double-blinded, phase 2 clinical trial was conducted at two public hospitals in Denmark. We enrolled 64 men and women with increased fracture risk based on a T-score < -1.0 at the total hip or lumbar spine and/or low-energy fracture within three years of recruitment. Participants were randomised (1:1) to receive once-weekly subcutaneous semaglutide 1.0 mg or placebo. The primary outcome was changes in plasma (P)-PINP from baseline to week 52. Primary and safety outcomes were assessed and evaluated for all participants. This trial is complete and registered with ClinicalTrials.gov, NCT04702516. Findings: Between March 24 and December 8, 2021, 55 (86%) postmenopausal women and nine men with a mean age of 63 years (SD 5.5) and BMI of 27.5 kg/m2 (SD 4.5) were enrolled. There was no effect on changes in P-PINP from baseline to week 52 between the two groups (estimated treatment difference (ETD) semaglutide versus placebo 3.8 µg/L [95% CI -5.6 to 13.3]; p = 0.418), and no difference in P-PINP levels between groups at week 52 (semaglutide 64.3 µg/L versus placebo 62.3 µg/L [95% CI -10.8 to 15.0]; p = 0.749). The secondary outcomes showed higher plasma levels of bone resorption marker Collagen type I cross-linked C-terminal telopeptide (P-CTX) in the semaglutide group than in the placebo group (ETD 166.4 ng/L [95% CI 25.5-307.3]; p = 0.021). Compared to placebo, lumbar spine and total hip areal bone mineral densities (aBMD) were lower in the semaglutide group after 52 weeks ((ETD lumbar spine -0.018 g/cm3 [95% CI -0.031 to -0.005]; p = 0.007); ETD total hip -0.020 g/cm2 ([95% CI -0.032 to -0.008]; p = 0.001). Treatment differences in femoral neck aBMD were not observed ([95% CI [-0.017 to 0.006]; p = 0.328). Further, body weight was lower in the semaglutide group than in the placebo group after 52 weeks (ETD -6.8 kg [95% CI -8.8 to -4.7]; p < 0.001). Thirty-one [97%] in the semaglutide group and 18 [56%] in the placebo group experienced at least one adverse event, including four serious events (two in each group). No episodes of hypoglycaemia or deaths were reported. Interpretation: In adults with increased fracture risk, semaglutide once weekly did not increase bone formation based on the bone formation marker P-PINP. The observed increase in bone resorption in the semaglutide group may be explained by the accompanying weight loss. Funding: Region of Southern Denmark, Novo Nordisk Foundation, and Gangsted Foundation. Novo Nordisk provided the investigational drug and placebo.

2.
Bone ; 181: 117035, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38342278

RESUMEN

Legalized use of cannabis for medical or recreational use is becoming more and more common. With respect to potential side-effects on bone health only few clinical trials have been conducted - and with opposing results. Therefore, it seems that there is a need for more knowledge on the potential effects of cannabinoids on human bone cells. We studied the effect of cannabidiol (CBD) and Δ9-tetrahydrocannabinol (THC) (dose range from 0.3 to 30 µM) on human osteoclasts in mono- as well as in co-cultures with human osteoblast lineage cells. We have used CD14+ monocytes from anonymous blood donors to differentiate into osteoclasts, and human osteoblast lineage cells from outgrowths of human trabecular bone. Our results show that THC and CBD have dose-dependent effects on both human osteoclast fusion and bone resorption. In the lower dose ranges of THC and CBD, osteoclast fusion was unaffected while bone resorption was increased. At higher doses, both osteoclast fusion and bone resorption were inhibited. In co-cultures, both osteoclastic bone resorption and alkaline phosphatase activity of the osteoblast lineage cells were inhibited. Finally, we observed that the cannabinoid receptor CNR2 is more highly expressed than CNR1 in CD14+ monocytes and pre-osteoclasts, but also that differentiation to osteoclasts was coupled to a reduced expression of CNR2, in particular. Interestingly, under co-culture conditions, we only detected the expression of CNR2 but not CNR1 for both osteoclast as well as osteoblast lineage nuclei. In line with the existing literature on the effect of cannabinoids on bone cells, our current study shows both stimulatory and inhibitory effects. This highlights that potential unfavorable effects of cannabinoids on bone cells and bone health is a complex matter. The contradictory and lacking documentation for such potential unfavorable effects on bone health as well as other potential effects, should be taken into consideration when considering the use of cannabinoids for both medical and recreational use.


Asunto(s)
Resorción Ósea , Cannabidiol , Cannabinoides , Humanos , Cannabidiol/farmacología , Cannabidiol/metabolismo , Osteoclastos/metabolismo , Dronabinol/farmacología , Dronabinol/metabolismo , Cannabinoides/farmacología , Cannabinoides/metabolismo , Resorción Ósea/metabolismo
3.
Bone Res ; 12(1): 5, 2024 01 24.
Artículo en Inglés | MEDLINE | ID: mdl-38263167

RESUMEN

Enhanced osteoclastogenesis and osteoclast activity contribute to the development of osteoporosis, which is characterized by increased bone resorption and inadequate bone formation. As novel antiosteoporotic therapeutics are needed, understanding the genetic regulation of human osteoclastogenesis could help identify potential treatment targets. This study aimed to provide an overview of transcriptional reprogramming during human osteoclast differentiation. Osteoclasts were differentiated from CD14+ monocytes from eight female donors. RNA sequencing during differentiation revealed 8 980 differentially expressed genes grouped into eight temporal patterns conserved across donors. These patterns revealed distinct molecular functions associated with postmenopausal osteoporosis susceptibility genes based on RNA from iliac crest biopsies and bone mineral density SNPs. Network analyses revealed mutual dependencies between temporal expression patterns and provided insight into subtype-specific transcriptional networks. The donor-specific expression patterns revealed genes at the monocyte stage, such as filamin B (FLNB) and oxidized low-density lipoprotein receptor 1 (OLR1, encoding LOX-1), that are predictive of the resorptive activity of mature osteoclasts. The expression of differentially expressed G-protein coupled receptors was strong during osteoclast differentiation, and these receptors are associated with bone mineral density SNPs, suggesting that they play a pivotal role in osteoclast differentiation and activity. The regulatory effects of three differentially expressed G-protein coupled receptors were exemplified by in vitro pharmacological modulation of complement 5 A receptor 1 (C5AR1), somatostatin receptor 2 (SSTR2), and free fatty acid receptor 4 (FFAR4/GPR120). Activating C5AR1 enhanced osteoclast formation, while activating SSTR2 decreased the resorptive activity of mature osteoclasts, and activating FFAR4 decreased both the number and resorptive activity of mature osteoclasts. In conclusion, we report the occurrence of transcriptional reprogramming during human osteoclast differentiation and identified SSTR2 and FFAR4 as antiresorptive G-protein coupled receptors and FLNB and LOX-1 as potential molecular markers of osteoclast activity. These data can help future investigations identify molecular regulators of osteoclast differentiation and activity and provide the basis for novel antiosteoporotic targets.


Asunto(s)
Osteoclastos , Osteogénesis , Humanos , Femenino , Biopsia , Densidad Ósea , Filaminas , Receptores Depuradores de Clase E
4.
Eur J Endocrinol ; 188(1)2023 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-36747334

RESUMEN

OBJECTIVE: Drugs targeting the glucose-dependent insulinotropic polypeptide (GIP) receptor (GIPR) are emerging as treatments for type-2 diabetes and obesity. GIP acutely decreases serum markers of bone resorption and transiently increases bone formation markers in short-term clinical investigations. However, it is unknown whether GIP acts directly on bone cells to mediate these effects. Using a GIPR-specific antagonist, we aimed to assess whether GIP acts directly on primary human osteoclasts and osteoblasts. METHODS: Osteoclasts were differentiated from human CD14+ monocytes and osteoblasts from human bone. GIPR expression was determined using RNA-seq in primary human osteoclasts and in situ hybridization in human femoral bone. Osteoclastic resorptive activity was assessed using microscopy. GIPR signaling pathways in osteoclasts and osteoblasts were assessed using LANCE cAMP and AlphaLISA phosphorylation assays, intracellular calcium imaging and confocal microscopy. The bioenergetic profile of osteoclasts was evaluated using Seahorse XF-96. RESULTS: GIPR is robustly expressed in mature human osteoclasts. GIP inhibits osteoclastogenesis, delays bone resorption, and increases osteoclast apoptosis by acting upon multiple signaling pathways (Src, cAMP, Akt, p38, Akt, NFκB) to impair nuclear translocation of nuclear factor of activated T cells-1 (NFATc1) and nuclear factor-κB (NFκB). Osteoblasts also expressed GIPR, and GIP improved osteoblast survival. Decreased bone resorption and improved osteoblast survival were also observed after GIP treatment of osteoclast-osteoblast co-cultures. Antagonizing GIPR with GIP(3-30)NH2 abolished the effects of GIP on osteoclasts and osteoblasts. CONCLUSIONS: GIP inhibits bone resorption and improves survival of human osteoblasts, indicating that drugs targeting GIPR may impair bone resorption, whilst preserving bone formation.


Asunto(s)
Resorción Ósea , Osteoclastos , Humanos , Osteoclastos/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Huesos/metabolismo , Osteoblastos/metabolismo , Resorción Ósea/tratamiento farmacológico , Resorción Ósea/metabolismo , Diferenciación Celular
5.
Int J Mol Sci ; 23(13)2022 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-35806338

RESUMEN

Therapeutic glucocorticoids (GCs) are powerful anti-inflammatory tools in the management of chronic inflammatory diseases such as rheumatoid arthritis (RA). However, their actions on bone in this context are complex. The enzyme 11ß-hydroxysteroid dehydrogenase type 1 (11ß-HSD1) is a mediator of the anti-inflammatory actions of therapeutic glucocorticoids (GCs) in vivo. In this study we delineate the role of 11ß-HSD1 in the effects of GC on bone during inflammatory polyarthritis. Its function was assessed in bone biopsies from patients with RA and osteoarthritis, and in primary osteoblasts and osteoclasts. Bone metabolism was assessed in the TNF-tg model of polyarthritis treated with oral GC (corticosterone), in animals with global (TNF-tg11ßKO), mesenchymal (including osteoblast) (TNF-tg11ßflx/tw2cre) and myeloid (including osteoclast) (TNF-tg11ßflx/LysMcre) deletion. Bone parameters were assessed by micro-CT, static histomorphometry and serum metabolism markers. We observed a marked increase in 11ß-HSD1 activity in bone in RA relative to osteoarthritis bone, whilst the pro-inflammatory cytokine TNFα upregulated 11ß-HSD1 within osteoblasts and osteoclasts. In osteoclasts, 11ß-HSD1 mediated the suppression of bone resorption by GCs. Whilst corticosterone prevented the inflammatory loss of trabecular bone in TNF-tg animals, counterparts with global deletion of 11ß-HSD1 were resistant to these protective actions, characterised by increased osteoclastic bone resorption. Targeted deletion of 11ß-HSD1 within osteoclasts and myeloid derived cells partially reproduced the GC resistant phenotype. These data reveal the critical role of 11ß-HSD1 within bone and osteoclasts in mediating the suppression of inflammatory bone loss in response to therapeutic GCs in chronic inflammatory disease.


Asunto(s)
Artritis Reumatoide , Resorción Ósea , Osteoartritis , 11-beta-Hidroxiesteroide Deshidrogenasa de Tipo 1/genética , 11-beta-Hidroxiesteroide Deshidrogenasa de Tipo 1/metabolismo , Animales , Artritis Reumatoide/metabolismo , Resorción Ósea/metabolismo , Corticosterona/metabolismo , Glucocorticoides/metabolismo , Glucocorticoides/farmacología , Inflamación/patología , Osteoartritis/metabolismo , Osteoclastos/metabolismo
6.
J Clin Endocrinol Metab ; 107(6): 1529-1540, 2022 05 17.
Artículo en Inglés | MEDLINE | ID: mdl-35244717

RESUMEN

CONTEXT: Osteoporosis results from disturbances in bone formation and resorption. Recent nonhuman data suggest that the reproductive hormone kisspeptin directly stimulates osteoblast differentiation in vitro and thus could have clinical therapeutic potential. However, the effects of kisspeptin on human bone metabolism are currently unknown. OBJECTIVE: To assess the effects of kisspeptin on human bone metabolism in vitro and in vivo. METHODS: In vitro study: of Mono- and cocultures of human osteoblasts and osteoclasts treated with kisspeptin. Clinical study: Randomized, placebo-controlled, double-blind, 2-way crossover clinical study in 26 men investigating the effects of acute kisspeptin administration (90 minutes) on human bone metabolism, with blood sampling every 30 minutes to +90 minutes. Cells for the in vitro study were from 12 male blood donors and 8 patients undergoing hip replacement surgery. Twenty-six healthy eugonadal men (age 26.8 ±â€…5.8 years) were included in the clinical study. The intervention was Kisspeptin (vs placebo) administration. The main outcome measures were changes in bone parameters and turnover markers. RESULTS: Incubation with kisspeptin in vitro increased alkaline phosphatase levels in human bone marrow mesenchymal stem cells by 41.1% (P = .0022), and robustly inhibited osteoclastic resorptive activity by up to 53.4% (P < .0001), in a dose-dependent manner. Kisspeptin administration to healthy men increased osteoblast activity, as evidenced by a 20.3% maximal increase in total osteocalcin (P = .021) and 24.3% maximal increase in carboxylated osteocalcin levels (P = .014). CONCLUSION: Collectively, these data provide the first human evidence that kisspeptin promotes osteogenic differentiation of osteoblast progenitors and inhibits bone resorption in vitro. Furthermore, kisspeptin acutely increases the bone formation marker osteocalcin but not resorption markers in healthy men, independent of downstream sex steroid levels. Kisspeptin could therefore have clinical therapeutic application in the treatment of osteoporosis.


Asunto(s)
Resorción Ósea , Osteoporosis , Adulto , Resorción Ósea/metabolismo , Diferenciación Celular , Humanos , Kisspeptinas/metabolismo , Kisspeptinas/farmacología , Masculino , Osteoblastos , Osteocalcina , Osteogénesis , Osteoporosis/metabolismo , Adulto Joven
7.
Bone Rep ; 14: 100752, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33665235

RESUMEN

BACKGROUND: Biochemical markers of bone turnover are lower in patients with type 2 diabetes, which may be explained by genetic variants being associated with type 2 diabetes and bone turnover as well as environmental factors. We hypothesized that bone turnover markers associate with and predict changes in glucose homeostasis after control for genetics and shared environment. METHODS: 1071 healthy, non-diabetic (at baseline, 1997-2000) adult mono- and dizygotic twins participating in the prospective study GEMINAKAR were reassessed between 2010 and 2012 with clinical evaluation, biochemical tests and oral glucose tolerance test. Fasting bone turnover markers (CTX, P1NP and osteocalcin) were measured. The association between bone turnover, glucose homeostasis and the ability of bone turnover markers to predict changes in glucose homeostasis were assessed in cross-sectional and longitudinal analyses. Analyses were performed both at an individual level and adjusted for shared environmental and genetic factors. RESULTS: Glucose levels increased with age, and 33 (3%) participants had developed type 2 diabetes at follow-up. In women, bone turnover markers increased with age, whereas for men only osteocalcin increased with age. Bone turnover markers were not associated with fasting glucose, insulin, or HOMA-IR at baseline or follow-up before or after adjustment for age, sex, BMI, smoking, and use of medication at baseline. Variation in bone turnover markers was mainly explained by unique environmental factors, 70%, 70% and 55% for CTX, P1NP and osteocalcin, respectively, whereas additive genetic factors explained 7%, 13% and 45% of the variation in CTX, P1NP and osteocalcin. CONCLUSIONS: Bone turnover markers were not associated with baseline plasma glucose levels and did not predict changes in glucose homeostasis. Variation in bone turnover markers is mainly explained by environmental factors, however, compared to CTX and P1NP, genetic factors have a larger impact on osteocalcin levels.

8.
PLoS One ; 13(8): e0201642, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30130373

RESUMEN

INTRODUCTION: Central sensitization plays a pivotal role in maintenance of pain and is believed to be intricately involved in several chronic pain conditions. One clinical manifestation of central sensitization is secondary hyperalgesia. The degree of secondary hyperalgesia presumably reflects individual levels of central sensitization. The objective of this study was to investigate the association between areas of secondary hyperalgesia and volumes of the caudate nuclei and other brain structures involved in pain processing. MATERIALS AND METHODS: We recruited 121 healthy male participants; 118 were included in the final analysis. All participants underwent whole brain magnetic resonance imaging (MRI). Prior to MRI, all participants underwent pain testing. Secondary hyperalgesia was induced by brief thermal sensitization. Additionally, we recorded heat pain detection thresholds (HPDT), pain during one minute thermal stimulation (p-TS) and results of the Pain Catastrophizing Scale (PCS) and Hospital Anxiety and Depression score (HADS). RESULTS: We found no significant associations between the size of the area of secondary hyperalgesia and the volume of the caudate nuclei or of the following structures: primary somatosensory cortex, anterior and mid cingulate cortex, putamen, nucleus accumbens, globus pallidus, insula and the cerebellum. Likewise, we found no significant associations between the volume of the caudate nuclei and HPDTs, p-TS, PCS and HADS. CONCLUSIONS: Our findings indicate that the size of the secondary hyperalgesia area is not associated with the volume of brain structures relevant for pain processing, suggesting that the propensity to develop central sensitization, assessed as secondary hyperalgesia, is not correlated to brain structure volume.


Asunto(s)
Núcleo Caudado/diagnóstico por imagen , Hiperalgesia/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Dolor/diagnóstico por imagen , Adulto , Sensibilización del Sistema Nervioso Central , Cerebelo/diagnóstico por imagen , Corteza Cerebral/diagnóstico por imagen , Giro del Cíngulo/diagnóstico por imagen , Voluntarios Sanos , Humanos , Hiperalgesia/etiología , Masculino , Núcleo Accumbens/diagnóstico por imagen , Umbral del Dolor , Putamen/diagnóstico por imagen , Adulto Joven
9.
Basic Clin Pharmacol Toxicol ; 122(1): 25-37, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28722834

RESUMEN

The relationship between gut and skeleton is increasingly recognized as part of the integrated physiology of the whole organism. The incretin hormones gastric inhibitory polypeptide (GIP) and glucagon-like peptide-1 (GLP-1) are secreted from the intestine in response to nutrient intake and exhibit several physiological functions including regulation of islet hormone secretion and glucose levels. A number of GLP-1 receptor agonists (GLP-1RAs) are currently used in treatment of type 2 diabetes and obesity. However, GIP and GLP-1 cognate receptors are widely expressed suggesting that incretin hormones mediate effects beyond control of glucose homeostasis, and reports on associations between incretin hormones and bone metabolism have emerged. The aim of this MiniReview was to provide an overview of current knowledge regarding the in vivo and in vitro effects of GIP and GLP-1 on bone metabolism. We identified a total of 30 pre-clinical and clinical investigations of the effects of GIP, GLP-1 and GLP-1RAs on bone turnover markers, bone mineral density (BMD), bone microarchitecture and fracture risk. Studies conducted in cell cultures and rodents demonstrated that GIP and GLP-1 play a role in regulating skeletal homeostasis, with pre-clinical data suggesting that GIP inhibits bone resorption whereas GLP-1 may promote bone formation and enhance bone material properties. These effects are not corroborated by clinical studies. While there is evidence of effects of GIP and GLP-1 on bone metabolism in pre-clinical investigations, clinical trials are needed to clarify whether similar effects are present and clinically relevant in humans.


Asunto(s)
Polipéptido Inhibidor Gástrico/metabolismo , Péptido 1 Similar al Glucagón/metabolismo , Receptor del Péptido 1 Similar al Glucagón/agonistas , Incretinas/farmacología , Osteoblastos/efectos de los fármacos , Osteoclastos/efectos de los fármacos , Animales , Densidad Ósea/efectos de los fármacos , Resorción Ósea/inducido químicamente , Huesos/citología , Huesos/efectos de los fármacos , Huesos/metabolismo , Huesos/fisiopatología , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Modelos Animales de Enfermedad , Fracturas Óseas/inducido químicamente , Receptor del Péptido 1 Similar al Glucagón/metabolismo , Humanos , Incretinas/uso terapéutico , Insulina/metabolismo , Obesidad/tratamiento farmacológico , Osteoblastos/metabolismo , Osteocalcina/metabolismo , Osteoclastos/metabolismo
10.
Ann Emerg Med ; 63(6): 699-703, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24268523

RESUMEN

STUDY OBJECTIVE: Initial out-of-hospital analgesia is sometimes hampered by difficulties in achieving intravenous access or lack of skills in administering intravenous opioids. We study the safety profile and apparent analgesic effect of intranasal fentanyl in the out-of-hospital setting. METHODS: In this prospective observational study, we administered intranasal fentanyl in the out-of-hospital setting to adults and children older than 8 years with severe pain resulting from orthopedic conditions, abdominal pain, or acute coronary syndrome refractory to nitroglycerin spray. Patients received 1 to 3 doses of either 50 or 100 µg, and the ambulance crew recorded adverse effects and numeric rating scale (0 to 10) pain scores before and after treatment. RESULTS: Our 903 evaluable patients received a mean cumulative fentanyl dose of 114 µg (range 50 to 300 µg). There were no serious adverse effects and no use of naloxone. Thirty-six patients (4%) experienced mild adverse effects: mild hypotension, nausea, vomiting, vertigo, abdominal pain, rash, or decrease of Glasgow Coma Scale score to 14. The median reduction in pain score was 3 (interquartile range 2 to 5) after fentanyl administration. CONCLUSION: The out-of-hospital administration of intranasal fentanyl in doses of 50 to 100 µg is safe and appears effective.


Asunto(s)
Analgésicos Opioides/administración & dosificación , Fentanilo/administración & dosificación , Dolor Abdominal/tratamiento farmacológico , Síndrome Coronario Agudo/tratamiento farmacológico , Dolor Agudo/tratamiento farmacológico , Administración Intranasal/efectos adversos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Analgésicos Opioides/efectos adversos , Analgésicos Opioides/uso terapéutico , Niño , Relación Dosis-Respuesta a Droga , Femenino , Fentanilo/efectos adversos , Fentanilo/uso terapéutico , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Adulto Joven
11.
Biotechnol Bioeng ; 109(4): 950-61, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22095443

RESUMEN

Modeling biotechnological processes is key to obtaining increased productivity and efficiency. Particularly crucial to successful modeling of such systems is the coupling of the physical transport phenomena and the biological activity in one model. We have applied a model for the expression of cellulosic enzymes by the filamentous fungus Trichoderma reesei and found excellent agreement with experimental data. The most influential factor was demonstrated to be viscosity and its influence on mass transfer. Not surprisingly, the biological model is also shown to have high influence on the model prediction. At different rates of agitation and aeration as well as headspace pressure, we can predict the energy efficiency of oxygen transfer, a key process parameter for economical production of industrial enzymes. An inverse relationship between the productivity and energy efficiency of the process was found. This modeling approach can be used by manufacturers to evaluate the enzyme fermentation process for a range of different process conditions with regard to energy efficiency.


Asunto(s)
Técnicas de Cultivo Celular por Lotes/métodos , Reactores Biológicos , Celulasa/biosíntesis , Fermentación , Proteínas Fúngicas/biosíntesis , Microbiología Industrial/métodos , Modelos Biológicos , Trichoderma/metabolismo , Técnicas de Cultivo Celular por Lotes/instrumentación , Lignina/metabolismo , Oxígeno/metabolismo , Reología , Termodinámica , Trichoderma/enzimología , Trichoderma/crecimiento & desarrollo , Viscosidad
12.
Eur J Anaesthesiol ; 28(12): 821-9, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21971206

RESUMEN

CONTEXT AND OBJECTIVE: Pain following craniotomy has been demonstrated to be frequent and moderate-to-severe in nature. In recent years, the focus on the challenges in treatment of postoperative pain following craniotomy has increased. Fear of using opioids because of their wide array of side-effects has led to the search for alternative analgesic options. The objective of this systematic review was to evaluate current evidence about analgesic therapy following craniotomy. DATA SOURCES: PubMed database, Embase, Cochrane library, Google scholar and the Cumulative Index to Nursing and Allied Health Literature. ELIGIBILITY CRITERIA: Randomised double-blinded placebo-controlled trials (RCTs) with pain or supplemental postoperative analgesic consumption as an endpoint were included in the analysis. RESULTS: A total of 34 RCTs were identified, and nine RCTs were included in the final analysis, with a total of 519 patients (251 control vs. 268 active treatment). Four treatment modalities - scalp infiltration (five RCTs), nerve scalp block (two RCTs), parecoxib (one RCT) and patient-controlled analgesia with morphine (one RCT) - were evaluated. Scalp infiltration with local anaesthetic may provide adequate analgesia in the first few postoperative hours, and nerve scalp block may provide longer lasting analgesia for about 6 h. Morphine was found to reduce total analgesic rescue doses with no significant effect on nausea and no other side-effects. No significant evidence was found to support the use of parecoxib in the treatment of postcraniotomy pain. CONCLUSION: No firm recommendations on analgesic therapy following craniotomy can be given because the number of well performed RCTs is limited and the study populations are very small. However, evidence on scalp infiltration suggests an analgesic effect in the first few postoperative hours. There is an urgent need for well performed RCTs on pain therapy following craniotomy.


Asunto(s)
Craneotomía , Medicina Basada en la Evidencia/métodos , Medicina Basada en la Evidencia/normas , Dolor Postoperatorio/terapia , Craneotomía/efectos adversos , Humanos , Dimensión del Dolor/métodos , Dimensión del Dolor/normas , Dolor Postoperatorio/etiología , Ensayos Clínicos Controlados Aleatorios como Asunto/métodos , Ensayos Clínicos Controlados Aleatorios como Asunto/normas , Resultado del Tratamiento
13.
Biotechnol Bioeng ; 108(8): 1828-40, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21370231

RESUMEN

The purpose of this article is to demonstrate how a model can be constructed such that the progress of a submerged fed-batch fermentation of a filamentous fungus can be predicted with acceptable accuracy. The studied process was enzyme production with Aspergillus oryzae in 550 L pilot plant stirred tank reactors. Different conditions of agitation and aeration were employed as well as two different impeller geometries. The limiting factor for the productivity was oxygen supply to the fermentation broth, and the carbon substrate feed flow rate was controlled by the dissolved oxygen tension. In order to predict the available oxygen transfer in the system, the stoichiometry of the reaction equation including maintenance substrate consumption was first determined. Mainly based on the biomass concentration a viscosity prediction model was constructed, because rising viscosity of the fermentation broth due to hyphal growth of the fungus leads to significant lower mass transfer towards the end of the fermentation process. Each compartment of the model was shown to predict the experimental results well. The overall model can be used to predict key process parameters at varying fermentation conditions.


Asunto(s)
Aspergillus oryzae/enzimología , Reactores Biológicos , Enzimas/biosíntesis , Aspergillus oryzae/crecimiento & desarrollo , Aspergillus oryzae/metabolismo , Carbono/metabolismo , Medios de Cultivo/química , Fermentación , Oxígeno/metabolismo
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