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1.
Front Endocrinol (Lausanne) ; 15: 1432928, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39104812

RESUMEN

We recently reported that a novel chimeric peptide (GEP44) targeting both the glucagon-like peptide-1 receptor (GLP-1R) and neuropeptide Y1- and Y2 receptor (Y1R and Y2R) reduced energy intake and body weight (BW) in diet-induced obese (DIO) rats. We hypothesized that GEP44 reduces energy intake and BW primarily through a GLP-1R dependent mechanism. To test this hypothesis, GLP-1R+/+ mice and GLP-1R null (GLP-1R-/-) mice were fed a high fat diet for 4 months to elicit diet-induced obesity prior to undergoing a sequential 3-day vehicle period, 3-day drug treatment (5, 10, 20 or 50 nmol/kg; GEP44 vs the selective GLP-1R agonist, exendin-4) and a 3-day washout. Energy intake, BW, core temperature and activity were measured daily. GEP44 (10, 20 and 50 nmol/kg) reduced BW after 3-day treatment in DIO male GLP-1R+/+ mice by -1.5 ± 0.6, -1.3 ± 0.4 and -1.9 ± 0.4 grams, respectively (P<0.05), with similar effects being observed in female GLP-1R+/+ mice. These effects were absent in male and female DIO GLP-1R-/- mice suggesting that GLP-1R signaling contributes to GEP44-elicited reduction of BW. Further, GEP44 decreased energy intake in both male and female DIO GLP-1R+/+ mice, but GEP44 appeared to produce more consistent effects across multiple doses in males. In GLP-1R-/- mice, the effects of GEP44 on energy intake were only observed in males and not females, suggesting that GEP44 may reduce energy intake, in part, through a GLP-1R independent mechanism in males. In addition, GEP44 reduced core temperature and activity in both male and female GLP-1R+/+ mice suggesting that it may also reduce energy expenditure. Lastly, we show that GEP44 reduced fasting blood glucose in DIO male and female mice through GLP-1R. Together, these findings support the hypothesis that the chimeric peptide, GEP44, reduces energy intake, BW, core temperature, and glucose levels in male and female DIO mice primarily through a GLP-1R dependent mechanism.


Asunto(s)
Peso Corporal , Dieta Alta en Grasa , Ingestión de Energía , Receptor del Péptido 1 Similar al Glucagón , Ratones Obesos , Obesidad , Animales , Receptor del Péptido 1 Similar al Glucagón/agonistas , Receptor del Péptido 1 Similar al Glucagón/metabolismo , Femenino , Masculino , Ratones , Obesidad/tratamiento farmacológico , Obesidad/metabolismo , Dieta Alta en Grasa/efectos adversos , Ingestión de Energía/efectos de los fármacos , Peso Corporal/efectos de los fármacos , Ratones Noqueados , Ratones Endogámicos C57BL
2.
Obes Res Clin Pract ; 2024 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-38987029

RESUMEN

BACKGROUND: Smith Magenis Syndrome (SMS) is a rare genetic disorder caused by RAI1 haploinsufficiency. Obesity in people with SMS is believed partially due to dysfunction of the proximal melanocortin 4 receptor (MC4R) pathway. We therefore studied effects of treatment with the MC4R agonist setmelanotide on obesity and hunger, as well as metabolic, cardiac and safety, in individuals with SMS. METHODS: People with SMS received once-daily setmelanotide injections, with the dose titrated bi-weekly to a maximum of 3 mg over ∼1 month; and a full-dose treatment duration of 3mo. The primary outcome was percent change in body weight. Secondary outcomes included hunger, waist circumference, body composition, and safety. RESULTS: 12 individuals, ages 11-39 y, enrolled and 10 completed the full-dose treatment phase. Mean percent change in body weight at end-treatment was - 0.28 % [(95 % CI, -2.1 % to 1.5 %; n = 12; P = 0.66]. Participants experienced a significant decrease in total cholesterol associated with a significant decrease in HDL-cholesterol and a trend for lower LDL-cholesterol. Self-reported hunger was reduced at end-treatment (p = 0.011). All participants reported adverse events (AEs), most commonly injection-site reactions and skin hyperpigmentation. No AEs led to withdrawal or death. CONCLUSIONS: In this trial, setmelanotide did not significantly reduce body weight in participants with SMS. Participants reported significant differences in hunger, but such self-reports are difficult to interpret without a placebo-treated group. The changes in lipid profiles require further investigation. Results of this study do not suggest that dysfunction of the proximal MC4R pathway is the main etiology for obesity in people with SMS.

3.
bioRxiv ; 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38826286

RESUMEN

We recently reported that a novel chimeric peptide (GEP44) targeting both the glucagon-like peptide-1 receptor (GLP-1R) and neuropeptide Y1- and Y2 receptor (Y1R and Y2R) reduced energy intake and body weight (BW) in diet-induced obese (DIO) rats. We hypothesized that GEP44 reduces energy intake and BW primarily through a GLP-1R dependent mechanism. To test this hypothesis, GLP-1R +/+ mice and GLP-1R null (GLP-1R -/- ) mice were fed a high fat diet for 4 months to elicit diet-induced obesity prior to undergoing a sequential 3-day vehicle period, 3-day drug treatment (5, 10, 20 or 50 nmol/kg; GEP44 vs the selective GLP-1R agonist, exendin-4) and a 3-day washout. Energy intake, BW, core temperature and activity were measured daily. GEP44 (10, 20 and 50 nmol/kg) reduced BW after 3-day treatment in DIO male GLP-1R +/+ mice by - 1.5±0.6, -1.3±0.4 and -1.9±0.4 grams, respectively ( P <0.05), with similar effects being observed in female GLP-1R +/+ mice. These effects were absent in male and female DIO GLP-1R -/- mice suggesting that GLP-1R signaling contributes to GEP44-elicited reduction of BW. Further, GEP44 decreased energy intake in both male and female DIO GLP-1R +/+ mice, but GEP44 appeared to produce more consistent effects across multiple doses in males. In GLP-1R -/- mice, the effects of GEP44 on energy intake were only observed in males and not females, suggesting that GEP44 may reduce energy intake, in part, through a GLP-1R independent mechanism in males. In addition, GEP44 reduced core temperature and activity in both male and female GLP-1R +/+ mice suggesting that it may also reduce energy expenditure. Lastly, we show that GEP44 reduced fasting blood glucose in DIO male and female mice through GLP-1R. Together, these findings support the hypothesis that the chimeric peptide, GEP44, reduces energy intake, BW, core temperature, and glucose levels in male and female DIO mice primarily through a GLP-1R dependent mechanism.

4.
Clin Nutr ; 43(7): 1782-1790, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38861891

RESUMEN

INTRODUCTION: While therapies based on endogenous gut peptides such as glucagon-like peptide-1 (GLP-1) receptor agonists (GLP-1RAs) have been compelling therapeutic agents for obesity and type 2 diabetes (T2D), only a few have achieved long-term weight loss and all have shown significant side-effects, including nausea/malaise and gastrointestinal ailments. OBJECTIVE: As the pathophysiology of obesity is driven by dysregulation of multiple, inter-related, pathways, we tested a novel peptide targeting multiple receptors of complementary neurocircuits regulating the controls of energy balance. METHODS: Response to daily injections of GEP44, a GLP-1R and neuropeptide Y1R and Y2R receptor (Y1R/Y2R) triple agonist was tested vs. the GLP-1R agonist liraglutide (LIRA) in diet-induced obese (DIO) male and female rats. Glucose tolerance tests after intraperitoneal injection of glucose (IPGTT) were performed at baseline and after 14-d of treatment in GEP44 treated rats. Other metabolic parameters were assessed in blood at the end of a 28-d intervention. RESULTS: Upon conclusion at 28-d, body weight reduction compared to vehicle was -15.6%/-11.9% in response to GEP44, vs. -9.7%/-5.1% after LIRA, males, and females, respectively. Significant reductions of cumulative food intake occurred over 28-d in female rats treated with GEP44 (-30%; p < 0.0001), vs. LIRA (-10%), and in male rats GEP44 (-39%; p < 0.0001), vs. LIRA (-20%; p = 0.003). In IPGTTs, a similar stimulation glucose induced insulin secretion was noted in rats treated with GEP44 and LIRA. CONCLUSION: The strong reductions of body weight in response to long-term applications of the triple agonist GEP44 confirms the therapeutic potential of targeting multiple receptors for achieving more robust and potentially more sustained improvement of energy balance.


Asunto(s)
Ingestión de Alimentos , Receptor del Péptido 1 Similar al Glucagón , Liraglutida , Obesidad , Animales , Obesidad/tratamiento farmacológico , Masculino , Ratas , Femenino , Receptor del Péptido 1 Similar al Glucagón/agonistas , Liraglutida/farmacología , Ingestión de Alimentos/efectos de los fármacos , Pérdida de Peso/efectos de los fármacos , Peso Corporal/efectos de los fármacos , Ratas Sprague-Dawley , Receptores de Neuropéptido Y/metabolismo , Dieta Alta en Grasa/efectos adversos , Glucemia/efectos de los fármacos , Glucemia/metabolismo , Insulina/sangre , Prueba de Tolerancia a la Glucosa
5.
Lancet Diabetes Endocrinol ; 12(6): 380-389, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38697184

RESUMEN

BACKGROUND: Hypothalamic obesity resulting from hypothalamic damage might affect melanocortin signalling. We investigated the melanocortin-4 receptor agonist setmelanotide for treatment of hypothalamic obesity. METHODS: This phase 2, open-label, multicentre trial was done in five centres in the USA. Eligible patients were aged between 6 and 40 years with obesity and history of hypothalamic injury or diagnosis of a non-malignant tumour affecting the hypothalamus that was treated with surgery, chemotherapy, or radiation. Setmelanotide was titrated up to a dose of 3·0 mg and administered subcutaneously once a day for a total duration of 16 weeks. The primary endpoint was the proportion of patients with a reduction in BMI of at least 5% from baseline after 16 weeks, compared with a historic control rate of less than 5% in this population. The primary endpoint was analysed using the full analysis set, which includes all patients with baseline data who received at least one dose of setmelanotide. Safety was assessed in all patients who received at least one dose of study drug. This trial is registered with ClinicalTrials.gov (NCT04725240) and is complete. FINDINGS: Between June 6, 2021, and Jan 13, 2022, 19 patients were screened for inclusion. One patient was excluded, and 18 were enrolled and received at least one dose of setmelanotide. Patients were primarily White (n=14 [78%]) and male (n=11 [61%]). Enrolled patients had a mean age of 15·0 years (SD 5·3) and a mean BMI of 38·0 kg/m2 (SD 6·5). Of 18 patients enrolled, 16 (89%) of 18 patients completed the study and met the primary endpoint of reduction in BMI of at least 5% from baseline after 16 weeks (p<0·0001). The mean reduction in BMI across all patients was 15% (SD 10). A composite proportion of patients had a clinically meaningful change (89%, 90% CI 69-98%; p<0·0001), comprising a reduction in BMI Z score of at least 0·2 points for patients younger than 18 years (92%, 68-100%; p<0·0001) and reduction in bodyweight of at least 5% for patients aged 18 years or older (80%, 34-99%; p<0·0001). Patients aged 12 years or older had a mean reduction in hunger score of 45%. Frequent adverse events included nausea (61%), vomiting (33%), skin hyperpigmentation (33%), and diarrhoea (22%). Of 14 patients who continued treatment in a long-term extension study (NCT03651765), 12 completed at least 12 months of treatment at the time of publication and had a mean change in BMI of -26% (SD 12) from index trial baseline. INTERPRETATION: These findings support setmelanotide as a novel effective treatment of hypothalamic obesity. FUNDING: Rhythm Pharmaceuticals.


Asunto(s)
Enfermedades Hipotalámicas , Obesidad , alfa-MSH , Humanos , Masculino , Femenino , Adulto , Adolescente , Obesidad/tratamiento farmacológico , Adulto Joven , Enfermedades Hipotalámicas/tratamiento farmacológico , Niño , alfa-MSH/análogos & derivados , alfa-MSH/uso terapéutico , alfa-MSH/administración & dosificación , Receptor de Melanocortina Tipo 4/agonistas , Resultado del Tratamiento , Índice de Masa Corporal
6.
Lancet ; 403(10442): 2395-2404, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38761811

RESUMEN

BACKGROUND: It is unknown whether decompressive craniectomy improves clinical outcome for people with spontaneous severe deep intracerebral haemorrhage. The SWITCH trial aimed to assess whether decompressive craniectomy plus best medical treatment in these patients improves outcome at 6 months compared to best medical treatment alone. METHODS: In this multicentre, randomised, open-label, assessor-blinded trial conducted in 42 stroke centres in Austria, Belgium, Finland, France, Germany, the Netherlands, Spain, Sweden, and Switzerland, adults (18-75 years) with a severe intracerebral haemorrhage involving the basal ganglia or thalamus were randomly assigned to receive either decompressive craniectomy plus best medical treatment or best medical treatment alone. The primary outcome was a score of 5-6 on the modified Rankin Scale (mRS) at 180 days, analysed in the intention-to-treat population. This trial is registered with ClincalTrials.gov, NCT02258919, and is completed. FINDINGS: SWITCH had to be stopped early due to lack of funding. Between Oct 6, 2014, and April 4, 2023, 201 individuals were randomly assigned and 197 gave delayed informed consent (96 decompressive craniectomy plus best medical treatment, 101 best medical treatment). 63 (32%) were women and 134 (68%) men, the median age was 61 years (IQR 51-68), and the median haematoma volume 57 mL (IQR 44-74). 42 (44%) of 95 participants assigned to decompressive craniectomy plus best medical treatment and 55 (58%) assigned to best medical treatment alone had an mRS of 5-6 at 180 days (adjusted risk ratio [aRR] 0·77, 95% CI 0·59 to 1·01, adjusted risk difference [aRD] -13%, 95% CI -26 to 0, p=0·057). In the per-protocol analysis, 36 (47%) of 77 participants in the decompressive craniectomy plus best medical treatment group and 44 (60%) of 73 in the best medical treatment alone group had an mRS of 5-6 (aRR 0·76, 95% CI 0·58 to 1·00, aRD -15%, 95% CI -28 to 0). Severe adverse events occurred in 42 (41%) of 103 participants receiving decompressive craniectomy plus best medical treatment and 41 (44%) of 94 receiving best medical treatment. INTERPRETATION: SWITCH provides weak evidence that decompressive craniectomy plus best medical treatment might be superior to best medical treatment alone in people with severe deep intracerebral haemorrhage. The results do not apply to intracerebral haemorrhage in other locations, and survival is associated with severe disability in both groups. FUNDING: Swiss National Science Foundation, Swiss Heart Foundation, Inselspital Stiftung, and Boehringer Ingelheim.


Asunto(s)
Hemorragia Cerebral , Craniectomía Descompresiva , Humanos , Persona de Mediana Edad , Masculino , Craniectomía Descompresiva/métodos , Femenino , Hemorragia Cerebral/cirugía , Anciano , Adulto , Resultado del Tratamiento , Terapia Combinada
7.
J Neurol ; 271(7): 4423-4429, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38676723

RESUMEN

BACKGROUND: Acute basilar artery occlusion is a life-threatening medical emergency with a highly elevated mortality rate when left untreated. Little is known about symptoms and clinical progression of chronic occlusions. The aim of this study was to systematically analyze the clinical presentation of patients with chronic basilar artery occlusion (CBAO). METHODS: Monocentric retrospective analysis of adult patients with CBAO was treated between 2015 and 2023 in the Department of Neurology, Klinikum Kassel. Inclusion criteria were basilar artery occlusion without brainstem infarction as well as patients with a basilar artery occlusion in whom revascularization could not be achieved and a follow-up period of at least 3 months. RESULTS: A total of 15 patients were found. In five patients basilar artery occlusion was diagnosed as an incidental finding, four patients had neurological symptoms but no proven brainstem infarction (3 × transient ischemic attack, 1 × isolated posterior artery infarct) and six patients presented with acute basilar artery occlusion and a follow-up > 3 months. The most common site of occlusion was midbasilar (80%, n = 12), isolated (n = 7) or in combination with other locations (n = 5). In all cases collateralization could be demonstrated by the posterior communicating arteries. The most common vascular risk factors (VRF) were hypertension (100%) and hypercholesterolemia (67%). CONCLUSIONS: Patients with CBAO may present with only mild symptoms or may even be asymptomatic. This condition may be survived for a long time. The high percentage of vascular risk factors and further cerebral vessel occlusions suggest arteriosclerosis as the major causing factor of CBAO.


Asunto(s)
Insuficiencia Vertebrobasilar , Humanos , Masculino , Femenino , Estudios Retrospectivos , Persona de Mediana Edad , Anciano , Insuficiencia Vertebrobasilar/diagnóstico por imagen , Insuficiencia Vertebrobasilar/complicaciones , Adulto , Enfermedad Crónica , Arteria Basilar/diagnóstico por imagen , Arteria Basilar/patología , Estudios de Seguimiento , Anciano de 80 o más Años
8.
Pediatr Radiol ; 54(7): 1168-1179, 2024 06.
Artículo en Inglés | MEDLINE | ID: mdl-38687346

RESUMEN

BACKGROUND: Idiopathic scoliosis is common in adolescence. Due to the rapid growth of the spine, it must be monitored closely with radiographs to ensure timely intervention when therapy is needed. As these radiographs continue into young adulthood, patients are repeatedly exposed to ionizing radiation. OBJECTIVE: This study aimed to investigate whether real-time magnetic resonance imaging (MRI) is equivalent to conventional radiography in juvenile idiopathic scoliosis for determining curvature, rotation and the Risser stage. Additionally, the time requirement should be quantified. MATERIALS AND METHODS: Children with idiopathic scoliosis who had postero-anterior whole-spine radiography for clinical indications were included in this prospective study. A real-time spine MRI was performed at 3 tesla in the supine position, capturing images in both the coronal and sagittal planes. The scoliosis was assessed using Cobb angle, rotation was evaluated based on Nash and Moe criteria, and the Risser stage was determined for each modality. The correlations between modalities and a correction factor for the Cobb angle between the standing and supine position were calculated. RESULTS: A total of 33 children (aged 5-17 years), who met the inclusion criteria, were recruited. The Cobb angle (R2 = 0.972; P < 0.01) was positively correlated with a correction factor of 1.07 between modalities. Additionally, the degree of rotation (R2 = 0.92; P < 0.01) and the Risser stage (R2 = 0.93; P < 0.01) demonstrated a strong correlation. CONCLUSION: Real-time MRI is equivalent to conventional radiography in determining baseline parameters. Furthermore, it is radiation-free and less time-consuming.


Asunto(s)
Imagen por Resonancia Magnética , Escoliosis , Humanos , Escoliosis/diagnóstico por imagen , Adolescente , Niño , Masculino , Femenino , Imagen por Resonancia Magnética/métodos , Preescolar , Estudios Prospectivos , Radiografía/métodos
9.
Chemistry ; 30(35): e202400783, 2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38629399

RESUMEN

Glycosaminoglycans (GAGs) are linear and acidic polysaccharides. They are ubiquitous molecules, which are involved in a wide range of biological processes. Despite being structurally simple at first glance, with a repeating backbone of alternating hexuronic acid and hexosamine dimers, GAGs display a highly complex structure, which predominantly results from their heterogeneous sulfation patterns. The commonly applied method for compositional analysis of all GAGs is "disaccharide analysis." In this process, GAGs are enzymatically depolymerized into disaccharides, derivatized with a fluorescent label, and then analysed through liquid chromatography. The limiting factor in the high throughput analysis of GAG disaccharides is the time-consuming liquid chromatography. To address this limitation, we here utilized trapped ion mobility-mass spectrometry (TIM-MS) for the separation of isomeric GAG disaccharides, which reduces the measurement time from hours to a few minutes. A full set of disaccharides comprises twelve structures, with eight possessing isomers. Most disaccharides cannot be differentiated by TIM-MS in underivatized form. Therefore, we developed chemical modifications to reduce sample complexity and enhance differentiability. Quantification is performed using stable isotope labelled standards, which are easily available due to the nature of the performed modifications.


Asunto(s)
Disacáridos , Glicosaminoglicanos , Disacáridos/química , Disacáridos/análisis , Glicosaminoglicanos/química , Glicosaminoglicanos/análisis , Espectrometría de Movilidad Iónica/métodos , Espectrometría de Masas/métodos , Isomerismo , Cromatografía Liquida/métodos
10.
Telemed J E Health ; 30(7): e2013-e2023, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38683593

RESUMEN

Background: Telemedicine improves access to specialized medical expertise, as required for paroxysmal disorders. The Epilepsy Network Hessen Evaluation (ENHE) is a pilot cross-sectoral teleconsultation network connecting primary neurologists and pediatricians with epilepsy centers in Hessen, a federal German state. Methods: We prospectively and longitudinally evaluated telehealthcare in the ENHE. Participating physicians rated each consultation for satisfaction and impact on further management. The survey was administered at each consultation and 3 months later. Results: We analyzed 129 consultations involving 114 adult and pediatric patients. Their mean age was 34 years (standard deviation: 26, range: 0.1-91 years), 48% were female, and 34% were children and adolescents. The most common consultation requests were co-evaluation of an electroencephalogram (electroencephalogram [EEG]; 76%) and therapeutic (33%) and differential diagnosis (24%) concerns. Physicians transmitted one paraclinical examination on average (range: 1-4), predominantly EEG (85%), followed by magnetic resonance imaging (17%) and written records (9%). Response rates were 72% for the initial and 67% for the follow-up survey. Across respondents, 99% (n = 92) were satisfied with the ENHE. Overall, 80% of the consultations contributed to the diagnosis, and 90% were considered helpful for treatment, influencing it in 71% of cases. Seizure frequency had decreased more often (96%) than increased (4%) at 3 months. The initial diagnosis was confirmed in 78% of patients. Discussion: In this pilot teleconsultation network for paroxysmal disorders, diagnostic and therapeutic advice was perceived as helpful. Clinical outcomes were largely positive, suggesting tele-epileptology is viable for paroxysmal (seizure) disorders.


Asunto(s)
Epilepsia , Consulta Remota , Humanos , Femenino , Epilepsia/diagnóstico , Masculino , Adulto , Adolescente , Niño , Alemania , Persona de Mediana Edad , Estudios Longitudinales , Adulto Joven , Anciano , Preescolar , Lactante , Estudios Prospectivos , Anciano de 80 o más Años , Consulta Remota/estadística & datos numéricos , Telemedicina/estadística & datos numéricos , Electroencefalografía , Satisfacción del Paciente , Derivación y Consulta/estadística & datos numéricos
11.
Front Physiol ; 15: 1368033, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38516212

RESUMEN

Background: Team handball involves a tremendous amount of shoulder motion with high forces during repeated extended external range of motion. This causes shoulder complaints and overuse injuries. While eccentric training for the lower extremity shows preventive effects by improving strength, range of motion and fascicle length, there is a research gap for the shoulder joint and for advanced tissue characterization using diffusion tensor imaging. Objectives: To investigate the effects of 6-week eccentric isokinetic resistance training on strength, flexibility, and fiber architecture characteristics of the external rotators compared to an active control group in junior male handball players. Methods: 15 subjects were randomly assigned to the eccentric training group and 14 subjects to the active control group (conventional preventive training). Primary outcome measures were eccentric and concentric isokinetic strength of the external rotators, range of motion, and muscle fascicle length and fascicle volume. Results: The intervention group, showed significant changes in eccentric strength (+15%). The supraspinatus and infraspinatus muscles showed significant increases in fascicle length (+13% and +8%), and in fractional anisotropy (+9% and +6%), which were significantly different from the control group. Conclusion: Eccentric isokinetic training has a significant effect on the function and macroscopic structure of the shoulder external rotators in male junior handball players. While strength parameters and muscle structure improved, range of motion did not change. This research helps understanding the physiology of muscle and the role of eccentric training on shoulder function and muscle structure. Furthermore, DTI was found to be a promising tool for advanced tissue characterization, and the in vivo derived data can also serve as model input variables and as a possibility to extend existing ex-vivo muscle models. Future research is needed for functional and structural changes following convenient eccentric field exercises.

12.
Diabetes Obes Metab ; 26 Suppl 2: 34-45, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38450938

RESUMEN

Hypothalamic obesity (HO) is a rare and complex disorder that confers substantial morbidity and excess mortality. HO is a unique subtype of obesity characterized by impairment in the key brain pathways that regulate energy intake and expenditure, autonomic nervous system function, and peripheral hormonal signalling. HO often occurs in the context of hypothalamic syndrome, a constellation of symptoms that follow from disruption of hypothalamic functions, for example, temperature regulation, sleep-wake circadian control, and energy balance. Genetic forms of HO, including the monogenic obesity syndromes, often impact central leptin-melanocortin pathways. Acquired forms of HO occur as a result of tumours impacting the hypothalamus, such as craniopharyngioma, surgery or radiation to treat those tumours, or other forms of hypothalamic damage, such as brain injury impacting the region. Risk for severe obesity following hypothalamic injury is increased with larger extent of hypothalamic damage or lesions that contain the medial and posterior hypothalamic nuclei that support melanocortin signalling pathways. Structural damage in these hypothalamic nuclei often leads to hyperphagia, central insulin and leptin resistance, decreased sympathetic activity, low energy expenditure, and increased energy storage in adipose tissue, the collective effect of which is rapid weight gain. Individuals with hyperphagia are perpetually hungry. They do not experience fullness at the end of a meal, nor do they feel satiated after meals, leading them to consume larger and more frequent meals. To date, most efforts to treat HO have been disappointing and met with limited, if any, long-term success. However, new treatments based on the distinct pathophysiology of disturbed energy homeostasis in acquired HO may hold promise for the future.


Asunto(s)
Craneofaringioma , Enfermedades Hipotalámicas , Neoplasias Hipofisarias , Humanos , Leptina/metabolismo , Enfermedades Hipotalámicas/complicaciones , Enfermedades Hipotalámicas/terapia , Enfermedades Hipotalámicas/metabolismo , Obesidad/complicaciones , Obesidad/terapia , Obesidad/genética , Hipotálamo/metabolismo , Craneofaringioma/complicaciones , Craneofaringioma/terapia , Craneofaringioma/metabolismo , Hiperfagia , Neoplasias Hipofisarias/metabolismo , Neoplasias Hipofisarias/patología , Melanocortinas/metabolismo , Metabolismo Energético/fisiología
13.
MethodsX ; 12: 102598, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38333546

RESUMEN

Understanding the occurrence and transformation of microplastics when released into the environment is essential for risk assessment. The use of biodegradable polymers in agriculture can help to reduce microplastic accumulation in soil, since released fragments of such materials are not persistent and are further transformed into CO2 and biomass (Wohlleben et al., 2023). To be able to monitor the fragmentation and biodegradation of these materials in soil, a validated extraction protocol is needed, which does not induce changes in the chemical and particle properties, additionally it should show high recoveries and matrix removal efficiency. A density-based extraction method in the centrifuge has the potential to remove a high amount of the soil matrix and is very selective for the polymer at the same time. Here we developed an efficient and non-destructive extraction protocol for biodegradable fragments from different soils using sequential centrifugation steps with varying densities and a freezing approach for sample collection. Although the focus of the present study was on biodegradable fragments, the technique can also be used for other types of microplastics with similar or lower density than the one tested for the method validation, but additional recovery tests for the target analyte are recommended.•A density-based extraction method for microplastics from soil, validated by recovery and stability tests using biodegradable polymers•Vessel changes and harsh chemical treatments are kept to a minimum.

14.
BMC Genomics ; 25(1): 6, 2024 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-38166563

RESUMEN

BACKGROUND: Microsporidia are a large taxon of intracellular pathogens characterized by extraordinarily streamlined genomes with unusually high sequence divergence and many species-specific adaptations. These unique factors pose challenges for traditional genome annotation methods based on sequence similarity. As a result, many of the microsporidian genomes sequenced to date contain numerous genes of unknown function. Recent innovations in rapid and accurate structure prediction and comparison, together with the growing amount of data in structural databases, provide new opportunities to assist in the functional annotation of newly sequenced genomes. RESULTS: In this study, we established a workflow that combines sequence and structure-based functional gene annotation approaches employing a ChimeraX plugin named ANNOTEX (Annotation Extension for ChimeraX), allowing for visual inspection and manual curation. We employed this workflow on a high-quality telomere-to-telomere sequenced tetraploid genome of Vairimorpha necatrix. First, the 3080 predicted protein-coding DNA sequences, of which 89% were confirmed with RNA sequencing data, were used as input. Next, ColabFold was used to create protein structure predictions, followed by a Foldseek search for structural matching to the PDB and AlphaFold databases. The subsequent manual curation, using sequence and structure-based hits, increased the accuracy and quality of the functional genome annotation compared to results using only traditional annotation tools. Our workflow resulted in a comprehensive description of the V. necatrix genome, along with a structural summary of the most prevalent protein groups, such as the ricin B lectin family. In addition, and to test our tool, we identified the functions of several previously uncharacterized Encephalitozoon cuniculi genes. CONCLUSION: We provide a new functional annotation tool for divergent organisms and employ it on a newly sequenced, high-quality microsporidian genome to shed light on this uncharacterized intracellular pathogen of Lepidoptera. The addition of a structure-based annotation approach can serve as a valuable template for studying other microsporidian or similarly divergent species.


Asunto(s)
Genoma , Genómica , Anotación de Secuencia Molecular
15.
MethodsX ; 12: 102560, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38292316

RESUMEN

Extracting microplastics from complex matrices poses challenges due to the potential impact of harsh chemical treatments on microplastic properties. For fate and hazard assessment reliable techniques are needed to not only quantify the particle number but also to assess the physicochemical properties of environmental microplastics with minimum changes induced by extraction. Here we present the method development for an innovative and non-destructive extraction protocol based on a switchable calcium chloride density separation column. In contrast to commonly reported extraction protocols, the presented technique is suitable for targeted microplastic property analysis (e.g., surface chemistry and texture) by keeping chemical treatments (such as oxidation and enzymatic digestion) to a minimum. By adjusting the temperature we can control the aggregate state of the highly concentrated salt solution, allowing to separate the microplastics from matrix by cutting of purified, solidified samples. Harsh chemical treatments are avoided, as well as obstruction of microplastic extraction by adsorption to matrix components when passing the tap at the bottom of traditional density separation funnels. The use of microplastics that were prelabeled with a fluorescence dye helped to solve difficulties observed during method development by visual inspection before measurement of extraction efficiency: We spiked a blank compost with low-density polyethylene (LDPE) and polyamide (PA). Additionally, UV aged LDPE was used to demonstrate applicability to more hydrophilic, more environmentally relevant microplastics. The obtained initial results show high recovery of both unaged and aged LDPE over 97 wt.-% and an efficient compost removal but a lower and less robust recovery (between 68 and 18 wt.-%) for PA particles that are more challenging to extract due to an unfortunate synergistic combination of smaller particle size and higher density. Method adaptation to other microplastic types may still be necessary. In short:•A low-cost and simple approach without oxidation to extract (pre-aged) microplastics from compost•Method development by visual observation using fluorescent labelled microplastics and method validation by spike-recovery tests.

16.
J Am Heart Assoc ; 13(2): e032300, 2024 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-38214300

RESUMEN

BACKGROUND: Stent thrombosis is a rare but deleterious event. Routine coronary angiography with percutaneous coronary intervention (PCI) is often deferred in the presence of laboratory markers of acute inflammation to prevent complications. The aim of this study was to investigate whether an acute inflammatory state is associated with an increased risk of early stent thrombosis. METHODS AND RESULTS: Within a prospective single-center registry, the association between preprocedural acute inflammatory activation, defined as C-reactive protein plasma levels >50 mg/L or a leukocyte count >12 g/L, and occurrence of early (≤30 days) stent thrombosis was evaluated. In total, 11 327 patients underwent PCI and of those, 6880 patients had laboratory results available. 49.6% of the study population received PCI for an acute coronary syndrome and 50.4% for stable ischemic heart disease. In patients with signs of acute inflammatory activation (24.9%), PCI was associated with a significantly increased risk for stent thrombosis (hazard ratio, 2.89; P<0.00001), independent of age, sex, kidney function, number and type of stents, presence of multivessel disease, choice of P2Y12 inhibitor, and clinical presentation. Elevated laboratory markers of acute inflammation were associated with the occurrence of stent thrombosis in both patients with acute coronary syndrome (hazard ratio, 2.63; P<0.001) and in patients with stable ischemic heart disease (hazard ratio, 3.57; P<0.001). CONCLUSIONS: An acute inflammatory state at the time of PCI was associated with a significantly increased risk of early stent thrombosis. Evidence of acute inflammation should result in deferred PCI in elective patients, while future studies are needed for patients with acute coronary syndrome.


Asunto(s)
Síndrome Coronario Agudo , Trombosis Coronaria , Isquemia Miocárdica , Intervención Coronaria Percutánea , Humanos , Síndrome Coronario Agudo/cirugía , Intervención Coronaria Percutánea/efectos adversos , Intervención Coronaria Percutánea/métodos , Inhibidores de Agregación Plaquetaria/efectos adversos , Estudios Prospectivos , Resultado del Tratamiento , Trombosis Coronaria/prevención & control , Stents/efectos adversos , Isquemia Miocárdica/complicaciones , Biomarcadores , Inflamación/complicaciones , Factores de Riesgo
17.
JAMA Neurol ; 81(2): 170-178, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38165690

RESUMEN

Importance: Stent retriever-based thrombectomy is highly beneficial in large vessel occlusion (LVO) strokes. Many stent retriever designs are currently available, but comparison of these technologies in well-conducted studies is lacking. Objective: To determine whether thrombectomy for LVO stroke with the pRESET stent retriever is noninferior to treatment with the Solitaire stent retriever. Design, Setting, and Participants: This study was a multicenter, prospective, randomized, controlled, open-label, adaptive, noninferiority trial with blinded primary end point evaluation. Between October 2019 and February 2022, multicenter participation occurred across 19 research hospitals and/or universities in the US and 5 in Germany. Patients with LVO stroke were enrolled and included up to 8 hours after symptom onset. Interventions: Patients underwent 1:1 randomization to thrombectomy with the pRESET or Solitaire stent retriever. Main Outcomes and Measures: The primary outcome was the difference in the rate of 90-day functional independence across the 2 devices, using a -12.5% noninferiority margin for the lower bound of the 1-sided 95% CI of the difference between pRESET and Solitaire retrievers. Results: Of 340 randomized patients, 170 (50.0%) were female, and the median (IQR) age was 73.0 (64.0-82.0) years. The study procedure was completed in 322 of the 340 randomized patients. The primary end point of 90-day functional independence was achieved by 95 patients (54.9%; 95% CI, 48.7-61.1) in the pRESET group and in 96 (57.5%; 95% CI, 51.2-63.8) in the Solitaire group (absolute difference, -2.57%; 95% CI, -11.42 to 6.28). As the lower bound of the 95% CI was greater than -12.5%, the pRESET retriever was deemed noninferior to the Solitaire retriever. The noninferiority of pRESET over Solitaire was also observed in the secondary clinical end point (90-day shift in modified Rankin Scale score) and in both angiographic end points (Expanded Treatment in Cerebral Infarction [eTICI] score of 2b50 or greater within 3 passes: 146 of 173 [84.4%] vs 149 of 167 [89.2%]; absolute difference, -4.83%; 95% CI, -10.84 to 1.19; eTICI of 2c or greater following the first pass: 76 of 173 [43.7%] vs 74 of 167 [44.3%]; absolute difference, -0.63%; 95% CI, -9.48 to 8.21). Symptomatic intracranial hemorrhage occurred in 0 patients in the pRESET group and 2 (1.2%) in the Solitaire group. Mortality occurred in 25 (14.5%) in the pRESET group and in 24 (14.4%) in the Solitaire group at 90 days. Findings of the per-protocol and as-treated analyses were in concordance with findings of the intention-to-treat analysis. Conclusions and Relevance: In this study, among patients with LVO stroke, thrombectomy with the pRESET stent retriever was noninferior to thrombectomy with the Solitaire stent retriever. Findings suggest that pRESET offers a safe and effective option for flow restoration and disability reduction in patients with LVO stroke.


Asunto(s)
Isquemia Encefálica , Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Isquemia Encefálica/complicaciones , Infarto Cerebral/complicaciones , Accidente Cerebrovascular Isquémico/complicaciones , Estudios Prospectivos , Stents , Accidente Cerebrovascular/cirugía , Accidente Cerebrovascular/complicaciones , Trombectomía/métodos , Resultado del Tratamiento , Persona de Mediana Edad
18.
Neurocrit Care ; 40(2): 621-632, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37498459

RESUMEN

BACKGROUND: Clinical observations indicated that vaccine-induced immune thrombosis with thrombocytopenia (VITT)-associated cerebral venous sinus thrombosis (CVST) often has a space-occupying effect and thus necessitates decompressive surgery (DS). While comparing with non-VITT CVST, this study explored whether VITT-associated CVST exhibits a more fulminant clinical course, different perioperative and intensive care unit management, and worse long-term outcome. METHODS: This multicenter, retrospective cohort study collected patient data from 12 tertiary centers to address priorly formulated hypotheses concerning the clinical course, the perioperative management with related complications, extracerebral complications, and the functional outcome (modified Rankin Scale) in patients with VITT-associated and non-VITT CVST, both with DS. RESULTS: Both groups, each with 16 patients, were balanced regarding demographics, kind of clinical symptoms, and radiological findings at hospital admission. Severity of neurological symptoms, assessed with the National Institute of Health Stroke Scale, was similar between groups at admission and before surgery, whereas more patients with VITT-associated CVST showed a relevant midline shift (≥ 4 mm) before surgery (100% vs. 68.8%, p = 0.043). Patients with VITT-associated CVST tended to undergo DS early, i.e., ≤ 24 h after hospital admission (p = 0.077). Patients with VITT-associated CVST more frequently received platelet transfusion, tranexamic acid, and fibrinogen perioperatively. The postoperative management was comparable, and complications were evenly distributed. More patients with VITT-associated CVST achieved a favorable outcome (modified Rankin Scale ≤ 3) at 3 months (p = 0.043). CONCLUSIONS: Although the prediction of individual courses remains challenging, DS should be considered early in VITT-associated CVST because an overall favorable outcome appears achievable in these patients.


Asunto(s)
Trombosis de los Senos Intracraneales , Trombocitopenia , Trombosis , Humanos , Estudios Retrospectivos , Trombosis de los Senos Intracraneales/etiología , Trombosis de los Senos Intracraneales/cirugía , Trombosis/complicaciones , Trombocitopenia/inducido químicamente , Progresión de la Enfermedad
19.
J Neurol ; 271(1): 564-574, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37923937

RESUMEN

Myasthenic crisis (MC) requiring mechanical ventilation is a serious complication of myasthenia gravis (MG). Here we analyze the frequency and risk factors of weaning- and extubation failure as well as its impact on the clinical course in a large cohort. We performed a retrospective chart review on patients treated for MC in 12 German neurological departments between 2006 and 2015. Weaning failure (WF) was defined as negative spontaneous breathing trial, primary tracheostomy, or extubation failure (EF) (reintubation or death). WF occurred in 138 episodes (64.2%). Older Age (p = 0.039), multiple comorbidities (≥ 3) (p = 0.007, OR = 4.04), late-onset MG (p = 0.004, OR = 2.84), complications like atelectasis (p = 0.008, OR = 3.40), pneumonia (p < 0.0001, OR = 3.45), cardio-pulmonary resuscitation (p = 0.005, OR = 5.00) and sepsis (p = 0.02, OR = 2.57) were associated with WF. WF occurred often in patients treated with intravenous immungloblins (IVIG) (p = 0.002, OR = 2.53), whereas WF was less often under first-line therapy with plasma exchange or immunoadsorption (p = 0.07, OR = 0.57). EF was observed in 58 of 135 episodes (43.0%) after first extubation attempt and was related with prolonged mechanical ventilation, intensive care unit stay and hospital stay (p ≤ 0.0001 for all). Extubation success was most likely in a time window for extubation between day 7 and 12 after intubation (p = 0.06, OR = 2.12). We conclude that WF and EF occur very often in MC and are associated with poor outcome. Older age, multiple comorbidities and development of cardiac and pulmonary complications are associated with a higher risk of WF and EF. Our data suggest that WF occurs less frequently under first-line plasma exchange/immunoadsorption compared with first-line use of IVIG.


Asunto(s)
Miastenia Gravis , Desconexión del Ventilador , Humanos , Desconexión del Ventilador/efectos adversos , Estudios Retrospectivos , Extubación Traqueal/efectos adversos , Inmunoglobulinas Intravenosas , Respiración Artificial , Miastenia Gravis/terapia , Miastenia Gravis/complicaciones
20.
PLoS One ; 18(12): e0293439, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38113203

RESUMEN

Strengthening the rotator cuff muscles is important for injury prevention and rehabilitation. Since muscle fascicle length improves motor performance and is suggested to reduce the risk of injury for the hamstring, it may be an important variable to promote multidirectional changes in the function and macroscopic structure for the shoulder. Recent literature reviews overwhelmingly suggest that eccentric exercises improve fascicle length and functional measures for the lower limb. However, there is a research gap for the shoulder. Since ultrasound imaging is the most commonly used imaging technique to quantify muscle structure, but has yielded heterogeneous results in different studies, there is another issue and a research gap for the imaging method. Based on the research gaps, the purpose of this study was to evaluate the effects of standardized eccentric strength training on the function and structure of the external rotator cuff muscles using an isokinetic dynamometer and MRI. Therefore, a preliminary pre-post intervention study was conducted and 16 physically active men were recruited in October 2021. For the right shoulder, an eccentric isokinetic training was performed twice a week for almost six weeks. The primary outcome measures (external rotators) were active and passive range of motion, eccentric and concentric torque at 30, 60, and 180°/s isokinetic speed, and fascicle length and fascicle volume for the supraspinatus and infraspinatus muscles. The findings show a training effect for the absolute mean values of eccentric strength (+24%, p = .008). The torque-angle relationship increased, especially in the final phase of range of motion, although a 4% (p = .002) decrease in passive range of motion was found in the stretch test. Positive changes in muscle structure were shown for the supraspinatus muscle fascicle length (+16%, p = .003) and fascicle volume (+19%, p = .002). Based on the study results, we can conclude that eccentric isokinetic training has a significant positive effect on the shoulder. To our knowledge, this is the first eccentric training study using both isokinetic dynamometer and muscle diffusion tensor imaging to access functional and structural changes in the human shoulder rotator cuff muscles. The methods were shown to be applicable for interventional studies. Based on these results, populations such as high-performance handball players with highly trained shoulders should be included in future studies.


Asunto(s)
Imagen de Difusión Tensora , Hombro , Masculino , Humanos , Hombro/diagnóstico por imagen , Hombro/fisiología , Manguito de los Rotadores/diagnóstico por imagen , Manguito de los Rotadores/fisiología , Músculo Esquelético/diagnóstico por imagen , Músculo Esquelético/fisiología , Terapia por Ejercicio/métodos , Fuerza Muscular/fisiología , Torque
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