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1.
J Anat ; 244(1): 63-74, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37694853

RESUMO

The apophyseal growth plate of the greater trochanter, unlike most other growth plates of the human body, exhibits a curved morphology that results in a divergent pattern resembling an open crocodile mouth on plain antero-posterior radiographs. To quantify the angular alignment of the growth plate and to draw conclusions about the function of the muscles surrounding it, we analyzed 57 MRI images of 51 children and adolescents aged 3-17 years and of six adults aged 18-52 years. We measured the angulation of the plate relative to the horizontal plane (AY angle) and the trajectories of the muscles attaching to the greater trochanter of the proximal femur. From anterior to posterior, the AY angle shows a decrease of 33.44°. In the anterior third, the cartilage is angled at a mean of 51.64°, and in the posterior third, the mean angulation is 18.6°. This indicates that the cartilage in the anterior region of the greater trochanteric apophysis is subject to more vertically oriented force vectors compared to the posterior region, as the growth plates align perpendicular to the force vectors acting on them. Combining the measured muscle trajectories with the physiological cross-sectional areas (PCSA) available from the literature revealed that, in addition to the known internal and external lateral traction ligament systems, a third, dorsally located traction ligament system exists that may be responsible for the dorsal deformation of the AY angle.


Assuntos
Lâmina de Crescimento , Articulação do Quadril , Criança , Adulto , Adolescente , Humanos , Lâmina de Crescimento/diagnóstico por imagem , Fenômenos Biomecânicos , Articulação do Quadril/anatomia & histologia , Fêmur/diagnóstico por imagem , Fêmur/fisiologia , Músculos
2.
Int Orthop ; 48(8): 1971-1978, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38658421

RESUMO

PURPOSE: The Sanders Scoring System has revolutionized the way we assess the remaining growth potential of the skeleton. However, because it involves radiation exposure, it must be used with caution in children. The purpose of the study was to evaluate whether the Sanders skeletal maturity score (SMS) could be accurately determined using ultrasound (U). METHODS: We took radiographs (R) of the hand and performed U of the thumb and index finger in 115 patients between six and 19 years of age who were undergoing treatment for scoliosis or limb deformities. Paediatric orthopaedic surgeons, a paediatrician, and a paediatric radiologist were evaluated the blinded images. Those classified images are based on the SMS and the Thumb Ossification Composite Index (TOCI). RESULTS: Intrarater reliability was high for SMS and slightly weaker for TOCI, but still significant. Interrater reliability was clear for R and weaker for U in both staging systems. Ultimately, SMS 3 and 7 achieved the highest percentage of concordance (P) of 71.7% and 66.0%, respectively, when U was performed. Combining the clinically relevant groups of SMS 3&4 and SMS 7&8 also significantly increased peak scores (SMS 3 and 4 P = 76.7%; SMS 7 and 8 P = 79.7%). The probabilities of peak scores were significantly weaker when the TOCI score was examined. CONCLUSION: Our study shows that U can be used effectively especially to measure stages 3 and 4 and stages 7 and 8 of SMS. The U method is easy to use and therefore may offer advantages in clinical practice without the need for radiation exposure.


Assuntos
Determinação da Idade pelo Esqueleto , Tomada de Decisão Clínica , Ultrassonografia , Humanos , Criança , Adolescente , Masculino , Feminino , Ultrassonografia/métodos , Determinação da Idade pelo Esqueleto/métodos , Tomada de Decisão Clínica/métodos , Reprodutibilidade dos Testes , Adulto Jovem , Radiografia/métodos , Mãos/diagnóstico por imagem , Escoliose/diagnóstico por imagem , Variações Dependentes do Observador
3.
Mol Pharm ; 20(5): 2465-2476, 2023 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-36961431

RESUMO

Water-free preparation of protein delivery systems has the potential to overcome the limitations of hydrogel depot systems such as off-target reactions, functional group hydrolysis, and limited loading capacity. However, a major roadblock in the development and use of these systems is administration as implantation is often required. In this study, we developed a biodegradable and water-free injectable protein delivery system via inverse electron demand Diels-Alder reaction between norbornene- and tetrazine-functionalized four-armed poly(ethylene glycol) macromonomers. 1:1 mixtures of these precursors gelled rapidly in situ, taking less than 11 s to reach their gelation point. Methyl substitution of tetrazine slowed the gelation time and increased the cross-linking density, whereas oxygen incorporation into norbornene changed the mechanical properties. Introduction of hydrolytically cleavable groups enabled biodegradability. Using phenyl carbamate and phenyl carbonate ester groups, we could tune the stability. Controlled release of the protein surrogate glucose oxidase was achieved over a period of 500 days. The novel preparation method presented here is a promising step toward the development of water-free injectable protein depots for controlled drug delivery.


Assuntos
Polietilenoglicóis , Polímeros , Preparações de Ação Retardada , Hidrogéis , Sistemas de Liberação de Medicamentos , Proteínas
4.
Proc Natl Acad Sci U S A ; 116(44): 22269-22274, 2019 10 29.
Artigo em Inglês | MEDLINE | ID: mdl-31611400

RESUMO

Adrenocortical carcinomas (ACCs) are rare and highly malignant cancers associated with poor survival of patients. Currently, mitotane, a nonspecific derivative of the pesticide DDT (1,1-(dichlorobiphenyl)-2,2-dichloroethane), is used as the standard treatment, but its mechanism of action in ACCs remains elusive. Here we demonstrate that the human ACC NCI-H295R cell line is remarkably sensitive to induction of ferroptosis, while mitotane does not induce this iron-dependent mode of regulated necrosis. Supplementation with insulin, transferrin, and selenium (ITS) is commonly used to keep NCI-H295R cells in cell culture. We show that this supplementation prevents spontaneous ferroptosis, especially when it contains polyunsaturated fatty acids (PUFAs), such as linoleic acid. Inhibitors of apoptosis (zVAD, emricasan) do not prevent the mitotane-induced cell death but morphologically prevent membrane blebbing. The expression of glutathione peroxidase 4 (GPX4) in H295R cells, however, is significantly higher when compared to HT1080 fibrosarcoma cells, suggesting a role for ferroptosis. Direct inhibition of GPX4 in H295R cells led to high necrotic populations compared to control, while cotreatment with ferrostatin-1 (Fer-1) completely reverted ferroptosis. Interestingly, the analysis of public databases revealed that several key players of the ferroptosis pathway are hypermethylated and/or mutated in human ACCs. Finally, we also detected that growth hormone-releasing hormone (GHRH) antagonists, such as MIA602, kill H295R cells in a nonapoptotic manner. In summary, we found elevated expression of GPX4 and higher sensitivity to ferroptosis in ACCs. We hypothesize that instead of treatment with mitotane, human adrenocortical carcinomas may be much more sensitive to induction of ferroptosis.


Assuntos
Neoplasias do Córtex Suprarrenal/metabolismo , Carcinoma Adrenocortical/metabolismo , Ferroptose/efeitos dos fármacos , Células 3T3 , Animais , Apoptose/efeitos dos fármacos , Células HEK293 , Células HT29 , Humanos , Insulina/metabolismo , Ferro/metabolismo , Ácido Linoleico/metabolismo , Camundongos , Mitotano/toxicidade , Fosfolipídeo Hidroperóxido Glutationa Peroxidase/genética , Fosfolipídeo Hidroperóxido Glutationa Peroxidase/metabolismo , Selênio/metabolismo , Sermorelina/análogos & derivados , Sermorelina/farmacologia , Transferrina/metabolismo
5.
Biomacromolecules ; 22(8): 3223-3236, 2021 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-34270216

RESUMO

Off-target interactions between reactive hydrogel moieties and drug cargo as well as slow reaction kinetics and the absence of controlled protein release over an extended period of time are major drawbacks of chemically cross-linked hydrogels for biomedical applications. In this study, the inverse electron demand Diels-Alder (iEDDA) reaction between norbornene- and tetrazine-functionalized eight-armed poly(ethylene glycol) (PEG) macromonomers was used to overcome these obstacles. Oscillatory shear experiments revealed that the gel point of a 15% (w/v) eight-armed PEG hydrogel with a molecular weight of 10 kDa was less than 15 s, suggesting the potential for fast in situ gelation. However, the high-speed reaction kinetics result in a risk of premature gel formation that complicates the injection process. Therefore, we investigated the effect of polymer concentration, temperature, and chemical structure on the gelation time. The cross-linking reaction was further characterized regarding bioorthogonality. Only 11% of the model protein lysozyme was found to be PEGylated by the iEDDA reaction, whereas 51% interacted with the classical Diels-Alder reaction. After determination of the mesh size, fluorescein isothiocyanate-dextran was used to examine the release behavior of the hydrogels. When glucose oxidase was embedded into 15% (w/v) hydrogels, a controlled release over more than 250 days was achieved. Overall, the PEG-based hydrogels cross-linked via the fast iEDDA reaction represent a promising material for the long-term administration of biologics.


Assuntos
Elétrons , Hidrogéis , Peso Molecular , Polietilenoglicóis , Proteínas
6.
EMBO Rep ; 20(2)2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30622217

RESUMO

Several long non-coding RNAs (lncRNAs) act as regulators of cellular homeostasis; however, few of these molecules were functionally characterized in a mature human tissue environment. Here, we report that the lncRNA LINC00941 is a crucial regulator of human epidermal homeostasis. LINC00941 is enriched in progenitor keratinocytes and acts as a repressor of keratinocyte differentiation. Furthermore, LINC00941 represses SPRR5, a previously uncharacterized molecule, which functions as an essential positive regulator of keratinocyte differentiation. Interestingly, 54.8% of genes repressed in SPRR5-deficient epidermal tissue are induced in LINC00941-depleted organotypic epidermis, suggesting a common mode of action for both molecules.


Assuntos
Proteínas Ricas em Prolina do Estrato Córneo/genética , Células Epidérmicas/metabolismo , Epiderme/metabolismo , Homeostase , RNA Longo não Codificante/genética , Diferenciação Celular/genética , Proteínas Ricas em Prolina do Estrato Córneo/metabolismo , Técnicas de Inativação de Genes , Humanos , Queratinócitos/citologia , Queratinócitos/metabolismo , Transcrição Gênica
7.
Semin Musculoskelet Radiol ; 23(5): 477-488, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31556083

RESUMO

The basic law of mechanobiology states that the external form and internal architecture of the skeleton and joints follow the functional stimuli that act upon them. Radiographs and magnetic resonance imaging reflect the loading history of the growing child, enabling an experienced radiologist to analyze the clinical functioning of patients by interpreting imaging studies. Concerning the hip joint, the physes of the coxal femoral end, the coxal femoral epiphysis with its epiphyseal growth plate, as well as the apophysis of the greater trochanter with its trochanteric growth plate, are the essential organ structures subject to internal forces. They determine the definitive geometric shape of the proximal femur. Indirectly they influence the appearance of the acetabulum and the centration of the hip joint.


Assuntos
Desenvolvimento Ósseo/fisiologia , Articulação do Quadril/patologia , Articulação do Quadril/fisiologia , Adolescente , Fatores Etários , Criança , Pré-Escolar , Epífises/crescimento & desenvolvimento , Epífises/patologia , Epífises/fisiologia , Cabeça do Fêmur/crescimento & desenvolvimento , Cabeça do Fêmur/patologia , Cabeça do Fêmur/fisiologia , Lâmina de Crescimento/crescimento & desenvolvimento , Lâmina de Crescimento/patologia , Lâmina de Crescimento/fisiologia , Articulação do Quadril/crescimento & desenvolvimento , Humanos , Lactente , Recém-Nascido , Imageamento por Ressonância Magnética/métodos , Radiografia/métodos
8.
Mar Drugs ; 16(5)2018 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-29783778

RESUMO

Over 10% of pheochromocytoma and paraganglioma (PPGL) patients have malignant disease at their first presentation in the clinic. Development of malignancy and the underlying molecular pathways in PPGLs are poorly understood and efficient treatment strategies are missing. Marine sponges provide a natural source of promising anti-tumorigenic and anti-metastatic agents. We evaluate the anti-tumorigenic and anti-metastatic potential of Aeroplysinin-1 and Isofistularin-3, two secondary metabolites isolated from the marine sponge Aplysina aerophoba, on pheochromocytoma cells. Aeroplysinin-1 diminished the number of proliferating cells and reduced spheroid growth significantly. Beside these anti-tumorigenic activity, Aeroplysinin-1 decreased the migration ability of the cells significantly (p = 0.01), whereas, the invasion capacity was not affected. Aeroplysinin-1 diminished the high adhesion capacity of the MTT cells to collagen (p < 0.001) and, furthermore, reduced the ability to form spheroids significantly. Western Blot and qRT-PCR analysis showed a downregulation of integrin ß1 that might explain the lower adhesion and migration capacity after Aeroplysinin-1 treatment. Isofistularin-3 showed only a negligible influence on proliferative and pro-metastatic cell properties. These in vitro investigations show promise for the application of the sponge-derived marine drug, Aeroplysinin-1 as anti-tumorigenic and anti-metastatic agent against PPGLs for the first time.


Assuntos
Acetonitrilas/farmacologia , Neoplasias das Glândulas Suprarrenais/tratamento farmacológico , Alcaloides/farmacologia , Antineoplásicos/farmacologia , Cicloexenos/farmacologia , Feocromocitoma/tratamento farmacológico , Poríferos/metabolismo , Acetonitrilas/isolamento & purificação , Acetonitrilas/uso terapêutico , Neoplasias das Glândulas Suprarrenais/patologia , Alcaloides/isolamento & purificação , Alcaloides/uso terapêutico , Animais , Antineoplásicos/isolamento & purificação , Antineoplásicos/uso terapêutico , Carcinogênese/efeitos dos fármacos , Adesão Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Cicloexenos/isolamento & purificação , Cicloexenos/uso terapêutico , Regulação para Baixo , Integrina beta1/metabolismo , Masculino , Camundongos , Feocromocitoma/patologia , Ratos , Esferoides Celulares/efeitos dos fármacos
9.
Horm Metab Res ; 49(9): 701-706, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28759940

RESUMO

Inhibition of aldosterone synthase (CYP11B2) is an alternative treatment option to mineralocorticoid receptor antagonism to prevent harmful aldosterone effects. FAD286 is the best characterized aldosterone synthase inhibitor. However, to date, no study has used sensitive liquid chromatography-tandem mass spectrometry to characterize in detail the effect of FAD286 on the secreted steroid hormone profile of adrenocortical cells. Basal aldosterone production in NCI-H295R cells was detectable and 9-fold elevated after stimulation with angiotensin II. FAD286 inhibited this increase, showing a maximal effect at 10 nmol/l. Higher concentrations of FAD286 did not further reduce aldosterone concentrations, but showed a parallel reduction in corticosterone, cortisol and cortisone levels, reflecting additional inhibition of steroid-11ß-hydroxylase (CYP11B1). Pregnenolone, progesterone and 17-OH-progesterone levels remained unaffected. In conclusion, the aldosterone synthase inhibitor FAD286 lowers angiotensin II-induced aldosterone concentrations in adrenocortical cells but the relative lack of selectivity over CYP11B1 is evident at higher FAD286 concentrations.


Assuntos
Córtex Suprarrenal/citologia , Citocromo P-450 CYP11B2/antagonistas & inibidores , Inibidores Enzimáticos/farmacologia , Fadrozol/farmacologia , Hormônios/metabolismo , Esteroides/metabolismo , Aldosterona/metabolismo , Angiotensina II/farmacologia , Bloqueadores do Receptor Tipo 1 de Angiotensina II/farmacologia , Benzimidazóis/farmacologia , Compostos de Bifenilo , Linhagem Celular , Citocromo P-450 CYP11B2/genética , Citocromo P-450 CYP11B2/metabolismo , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Glucocorticoides/metabolismo , Humanos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptor Tipo 1 de Angiotensina/metabolismo , Tetrazóis/farmacologia
10.
J Insect Sci ; 17(2)2017 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-28931157

RESUMO

Temporal niche partitioning may result from interference competition if animals shift their activity patterns to avoid aggressive competitors. If doing so also shifts food sources, it is difficult to distinguish the effects of interference and consumptive competition in selecting for temporal niche shift. Bees compete for pollen and nectar from flowers through both interference and consumptive competition, and some species of bees have evolved nocturnality. Here, we use tropical forest canopy towers to observe bees (the night-flying sweat bees Megalopta genalis and M. centralis [Halictidae], honey bees, and stingless bees [Apidae]) visiting flowers of the balsa tree (Ochroma pyramalidae, Malvaceae). Because Ochroma flowers are open in the late afternoon through the night we can test the relative influence of each competition type on temporal nice. Niche shift due to consumptive competition predicts that Megalopta forage when resources are available: from afternoon into the night. Niche shift due to interference competition predicts that Megalopta forage only in the absence of diurnal bees. We found no overlap between diurnal bees and Megalopta in the evening, and only one instance of overlap in the morning, despite the abundance of pollen and nectar in the late afternoon and evening. This supports the hypothesis that Megalopta are avoiding interference competition, but not the hypothesis that they are limited by consumptive competition. We propose that the release from interference competition enables Megalopta to provision cells quickly, and spend most of their time investing in nest defense. Thus, increases in foraging efficiency directly resulting from temporal shifts to escape interference competition may indirectly lead to reduced predation and parasitism.


Assuntos
Abelhas/fisiologia , Comportamento Alimentar/fisiologia , Agressão , Animais , Bombacaceae/crescimento & desenvolvimento , Comportamento Competitivo , Feminino , Panamá , Fatores de Tempo
11.
J Am Chem Soc ; 136(5): 1730-3, 2014 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-24432762

RESUMO

Nanosheets of a crystalline 2D carbon nitride were obtained by ionothermal synthesis of the layered bulk material poly(triazine imide), PTI, followed by one-step liquid exfoliation in water. Triazine-based nanosheets are 1-2 nm in height and afford chemically and colloidally stable suspensions under both basic and acidic conditions. We use solid-state NMR spectroscopy of isotopically enriched, restacked nanosheets as a tool to indirectly monitor the exfoliation process and carve out the chemical changes occurring upon exfoliation, as well as to determine the nanosheet thickness. PTI nanosheets show significantly enhanced visible-light driven photocatalytic activity toward hydrogen evolution compared to their bulk counterpart, which highlights the crucial role of morphology and surface area on the photocatalytic performance of carbon nitride materials.

12.
Nucleic Acids Res ; 40(19): 9850-62, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22844086

RESUMO

MicroRNAs (miRNAs) are small noncoding RNAs that function in literally all cellular processes. miRNAs interact with Argonaute (Ago) proteins and guide them to specific target sites located in the 3'-untranslated region (3'-UTR) of target mRNAs leading to translational repression and deadenylation-induced mRNA degradation. Most miRNAs are processed from hairpin-structured precursors by the consecutive action of the RNase III enzymes Drosha and Dicer. However, processing of miR-451 is Dicer independent and cleavage is mediated by the endonuclease Ago2. Here we have characterized miR-451 sequence and structure requirements for processing as well as sorting of miRNAs into different Ago proteins. Pre-miR-451 appears to be optimized for Ago2 cleavage and changes result in reduced processing. In addition, we show that the mature miR-451 only associates with Ago2 suggesting that mature miRNAs are not exchanged between different members of the Ago protein family. Based on cloning and deep sequencing of endogenous miRNAs associated with Ago1-3, we do not find evidence for miRNA sorting in human cells. However, Ago identity appears to influence the length of some miRNAs, while others remain unaffected.


Assuntos
Proteínas Argonautas/metabolismo , MicroRNAs/metabolismo , Animais , Linhagem Celular , Humanos , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/química , Processamento Pós-Transcricional do RNA , RNA Interferente Pequeno/metabolismo
13.
Proc Natl Acad Sci U S A ; 108(33): 13722-7, 2011 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-21825133

RESUMO

Corticotropin-releasing hormone (CRH) and growth hormone-releasing hormone (GHRH), primarily characterized as neuroregulators of the hypothalamic-pituitary-adrenal axis, directly influence tissue-specific receptor-systems for CRH and GHRH in the endocrine pancreas. Here, we demonstrate the expression of mRNA for CRH and CRH-receptor type 1 (CRHR1) and of protein for CRHR1 in rat and human pancreatic islets and rat insulinoma cells. Activation of CRHR1 and GHRH-receptor significantly increased cell proliferation and reduced cell apoptosis. CRH stimulated both cellular content and release of insulin in rat islet and insulinoma cells. At the ultrastructural level, CRHR1 stimulation revealed a more active metabolic state with enlarged mitochondria. Moreover, glucocorticoids that promote glucose production are balanced by both 11b-hydroxysteroid dehydrogenase (11ß-HSD) isoforms; 11ß-HSD-type-1 and 11ß-HSD-type-2. We demonstrated expression of mRNA for 11ß-HSD-1 and 11ß-HSD-2 and protein for 11ß-HSD-1 in rat and human pancreatic islets and insulinoma cells. Quantitative real-time PCR revealed that stimulation of CRHR1 and GHRH-receptor affects the metabolism of insulinoma cells by down-regulating 11ß-HSD-1 and up-regulating 11ß-HSD-2. The 11ß-HSD enzyme activity was analyzed by measuring the production of cortisol from cortisone. Similarly, activation of CRHR1 resulted in reduced cortisol levels, indicating either decreased 11ß-HSD-1 enzyme activity or increased 11ß-HSD-2 enzyme activity; thus, activation of CRHR1 alters the glucocorticoid balance toward the inactive form. These data indicate that functional receptor systems for hypothalamic-releasing hormone agonists exist within the endocrine pancreas and influence synthesis of insulin and the pancreatic glucocorticoid shuttle. Agonists of CRHR1 and GHRH-receptor, therefore, may play an important role as novel therapeutic tools in the treatment of diabetes mellitus.


Assuntos
11-beta-Hidroxiesteroide Desidrogenases/fisiologia , Sistema Hipotálamo-Hipofisário/metabolismo , Ilhotas Pancreáticas/metabolismo , Hormônios Liberadores de Hormônios Hipofisários/fisiologia , Sistema Hipófise-Suprarrenal/metabolismo , Animais , Hormônio Liberador da Corticotropina , Humanos , Insulina/biossíntese , Insulinoma/patologia , RNA Mensageiro , Ratos , Receptores de Hormônio Liberador da Corticotropina/metabolismo , Receptores de Neuropeptídeos/metabolismo , Receptores de Hormônios Reguladores de Hormônio Hipofisário/metabolismo
14.
J Am Coll Emerg Physicians Open ; 5(1): e13091, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38179412

RESUMO

Objective: Critical illness is often accompanied by elevated blood glucose, which generally correlates with increased morbidity and mortality. Prehospital blood glucose (PBG) level might be a useful and easy-to-perform tool for risk assessment in emergency medicine. This retrospective single-center cohort study was designed to analyze the association of prehospital glucose measurements with hospitalization rate and in-hospital mortality. Methods: Records of 970 patients admitted to a university hospital by an emergency physician were analyzed. Patients with a PBG ≥140 mg/dL (G1, n = 394, equal to 7.8 mmol/L) were compared with patients with a PBG <140 mg/dL (G2, n = 576). Multivariable logistic regression models were used to correct for age, prediagnosed diabetes, and sex. Results: Five hundred thirty-four patients (55%) were hospitalized. In comparison to normoglycemic patients, hyperglycemic patients were more likely to be hospitalized with an adjusted odds ratio (OR) of 1.48 (95% confidence interval [CI] 1.11-1.97), more likely to be admitted to the intensive care unit (ICU) with an adjusted OR of 1.74 (95% CI 1.31-2.31) and more likely to die in the hospital with an adjusted OR of 1.84 (95% CI 0.96-3.53). Hospitalized hyperglycemic patients had a median length of stay of 6.0 days (interquartile range [IQR] 8.0) compared to 3.0 days (IQR 6.0) in the normoglycemic group (P < 0.001). In the subgroup analysis of cases without known diabetes, patients with PBG ≥140 mg/dL were more likely to be hospitalized with an adjusted OR of 1.49 (95% CI 1.10-2.03) and more likely to be admitted to ICU/intermediate care with an adjusted OR of 1.80 (95% CI 1.32-2.45), compared to normoglycemic patients. Conclusion: Elevated PBG ≥140 mg/dL was associated with a higher hospitalization risk, a longer length of stay, and a higher mortality risk and may therefore be included in risk assessment scores.

15.
Int J Pharm ; 657: 124131, 2024 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-38643811

RESUMO

Immunization is a straightforward concept but remains for some pathogens like HIV-1 a challenge. Thus, new approaches towards increasing the efficacy of vaccines are required to turn the tide. There is increasing evidence that antigen exposure over several days to weeks induces a much stronger and more sustained immune response compared to traditional bolus injection, which usually leads to antigen elimination from the body within a couple of days. Therefore, we developed a poly(ethylene) glycol (PEG) hydrogel platform to investigate the principal feasibility of a sustained release of antigens to mimic natural infection kinetics. Eight-and four-armed PEG macromonomers of different MWs (10, 20, and 40 kDa) were end-group functionalized to allow for hydrogel formation via covalent cross-linking. An HIV-1 envelope (Env) antigen in its trimeric (Envtri) or monomeric (Envmono) form was applied. The soluble Env antigen was compared to a formulation of Env attached to silica nanoparticles (Env-SiNPs). The latter are known to have a higher immunogenicity compared to their soluble counterparts. Hydrogels were tunable regarding the rheological behavior allowing for different degradation times and release timeframes of Env-SiNPs over two to up to 50 days. Affinity measurements of the VCR01 antibody which specifically recognizes the CD4 binding site of Env, revealed that neither the integrity nor the functionality of Envmono-SiNPs (Kd = 2.1 ± 0.9 nM) and Envtri-SiNPs (Kd = 1.5 ± 1.3 nM), respectively, were impaired after release from the hydrogel (Kd before release: 2.1 ± 0.1 and 7.8 ± 5.3 nM, respectively). Finally, soluble Env and Env-SiNPs which are two physico-chemically distinct compounds, were co-delivered and shown to be sequentially released from one hydrogel which could be beneficial in terms of heterologous immunization or single dose vaccination. In summary, this study presents a tunable, versatile applicable, and effective delivery platform that could improve vaccination effectiveness also for other infectious diseases than HIV-1.


Assuntos
Vacinas contra a AIDS , Preparações de Ação Retardada , HIV-1 , Hidrogéis , Nanopartículas , Polietilenoglicóis , Hidrogéis/química , Nanopartículas/química , Vacinas contra a AIDS/administração & dosagem , Vacinas contra a AIDS/imunologia , Vacinas contra a AIDS/química , Polietilenoglicóis/química , HIV-1/imunologia , Dióxido de Silício/química , Humanos , Liberação Controlada de Fármacos , Produtos do Gene env do Vírus da Imunodeficiência Humana/imunologia , Produtos do Gene env do Vírus da Imunodeficiência Humana/química
16.
Theranostics ; 14(1): 17-32, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38164150

RESUMO

Radionuclide therapies are an important tool for the management of patients with neuroendocrine neoplasms (NENs). Especially [131I]MIBG and [177Lu]Lu-DOTA-TATE are routinely used for the treatment of a subset of NENs, including pheochromocytomas, paragangliomas and gastroenteropancreatic tumors. Some patients suffering from other forms of NENs, such as medullary thyroid carcinoma or neuroblastoma, were shown to respond to radionuclide therapy; however, no general recommendations exist. Although [131I]MIBG and [177Lu]Lu-DOTA-TATE can delay disease progression and improve quality of life, complete remissions are achieved rarely. Hence, better individually tailored combination regimes are required. This review summarizes currently applied radionuclide therapies in the context of NENs and informs about recent advances in the development of theranostic agents that might enable targeting subgroups of NENs that previously did not respond to [131I]MIBG or [177Lu]Lu-DOTA-TATE. Moreover, molecular pathways involved in NEN tumorigenesis and progression that mediate features of radioresistance and are particularly related to the stemness of cancer cells are discussed. Pharmacological inhibition of such pathways might result in radiosensitization or general complementary antitumor effects in patients with certain genetic, transcriptomic, or metabolic characteristics. Finally, we provide an overview of approved targeted agents that might be beneficial in combination with radionuclide therapies in the context of a personalized molecular profiling approach.


Assuntos
Carcinoma Neuroendócrino , Tumores Neuroendócrinos , Humanos , Tumores Neuroendócrinos/radioterapia , Tumores Neuroendócrinos/metabolismo , 3-Iodobenzilguanidina , Qualidade de Vida , Octreotida , Carcinoma Neuroendócrino/tratamento farmacológico , Radioisótopos/uso terapêutico
17.
Endocr Connect ; 13(3)2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38300808

RESUMO

Objective: Combination therapies with gut hormone analogs represent promising treatment strategies for obesity. This pilot study investigates the therapeutic potential of modulators of the glucagon-like peptide 1 (GLP-1) and neuropeptide Y (NPY) system using GLP-1 receptor agonists (semaglutide) and antagonists (exendin 9-39), as well as non-selective and NPY-Y2-receptor selective peptide tyrosine tyrosine (PYY) analogs (PYY3-36/NNC0165-0020 and NNC0165-1273) and an NPY-Y2 receptor antagonist (JNJ31020028). Methods: High-fat diet (HFD)-induced obese rats were randomized into following treatment groups: group 1, nonselective PYY analog + semaglutide (n = 4); group 2, non-selective and NPY-Y2 receptor selective PYY analog + semaglutide (n = 2); group 3, GLP-1 receptor antagonist + NPY-Y2 receptor antagonist (n = 3); group 4, semaglutide (n = 5); and group 5, control (n = 5). Animals had free access to HFD and low-fat diet. Food intake, HFD preference and body weight were measured daily. Results: A combinatory treatment with a non-selective PYY analog and semaglutide led to a maximum body weight loss of 14.0 ± 4.9% vs 9.9 ± 1.5% with semaglutide alone. Group 2 showed a maximum weight loss of 20.5 ± 2.4%. While HFD preference was decreased in group 2, a strong increase in HFD preference was detected in group 3. Conclusions: PYY analogs (especially NPY-Y2 selective receptor agonists) could represent a promising therapeutic approach for obesity in combination with GLP-1 receptor agonists. Additionally, combined GLP-1 and PYY3-36 receptor agonists might have beneficial effects on food preference.

18.
Proc Natl Acad Sci U S A ; 107(28): 12623-8, 2010 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-20616039

RESUMO

Therapeutic strategies for transplantation of pancreatic islet cells are urgently needed to expand beta-cell mass by stimulating islet cell proliferation and/or prolonging islet cell survival. Control of the islets by different growth factors provides a potential venue for augmenting beta-cell mass. In the present study, we show the expression of the biologically active splice variant-1 (SV-1) of growth hormone-releasing hormone (GHRH) receptor in rat insulinoma (INS-1) cells as well as in rat and human pancreatic islets. In studies in vitro of INS-1 cells, the GHRH agonist JI-36 caused a significant increase in cell proliferation and a reduction of cell apoptosis. JI-36 increased islet size and glucose-stimulated insulin secretion in isolated rat islets after 48-72 h. At the ultrastructural level, INS-1 cells treated with agonist JI-36 revealed a metabolic active stimulation state with increased cytoplasm. Coincubation with the GHRH antagonist MIA-602 reversed the actions of the agonist JI-36, indicating the specificity of this agonist. In vivo, the function of pancreatic islets was assessed by transplantation of rat islets under the kidney capsule of streptozotocin-induced diabetic non-obese diabetic-severe combined immunodeficiency (NOD-SCID) mice. Islets treated with GHRH agonist JI-36 were able to achieve normoglycemia earlier and more consistently than untreated islets. Furthermore, in contrast to diabetic animals transplanted with untreated islets, insulin response to an i.p. glucose tolerance test (IPGTT) in animals receiving islets treated with agonist Jl-36 was comparable to that of normal healthy mice. In conclusion, our study provides evidence that agonists of GHRH represent a promising pharmacological therapy aimed at promoting islet graft growth and proliferation in diabetic patients.


Assuntos
Ilhotas Pancreáticas/metabolismo , Ilhotas Pancreáticas/fisiologia , Animais , Apoptose , Proliferação de Células , Glucose/metabolismo , Teste de Tolerância a Glucose , Hormônio do Crescimento/metabolismo , Hormônio Liberador de Hormônio do Crescimento/metabolismo , Hormônios/metabolismo , Hormônio do Crescimento Humano/metabolismo , Humanos , Insulina/biossíntese , Insulina/metabolismo , Células Secretoras de Insulina/metabolismo , Células Secretoras de Insulina/fisiologia , Insulinoma/cirurgia , Ilhotas Pancreáticas/cirurgia , Masculino , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Ratos , Ratos Wistar
19.
Pharmacol Ther ; 251: 108549, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37879540

RESUMO

Obesity and its comorbidities, including type 2 diabetes mellitus, cardiovascular disease, heart failure and non-alcoholic liver disease are a major health and economic burden with steadily increasing numbers worldwide. The need for effective pharmacological treatment options is strong, but, until recently, only few drugs have proven sufficient efficacy and safety. This article provides a comprehensive overview of obesity and its comorbidities, with a special focus on organ-specific pathomechanisms. Bariatric surgery as the so far most-effective therapeutic strategy, current pharmacological treatment options and future treatment strategies will be discussed. An increasing knowledge about the gut-brain axis and especially the identification and physiology of incretins unfolds a high number of potential drug candidates with impressive weight-reducing potential. Future multi-modal therapeutic concepts in obesity treatment may surpass the effectivity of bariatric surgery not only with regard to weight loss, but also to associated comorbidities.


Assuntos
Cirurgia Bariátrica , Diabetes Mellitus Tipo 2 , Humanos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/cirurgia , Obesidade/epidemiologia , Obesidade/cirurgia , Comorbidade , Incretinas , Redução de Peso
20.
Sci Rep ; 13(1): 20538, 2023 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-37996429

RESUMO

Legg-Calvé-Perthes disease (LCPD) requires individualized treatment in order to regain a functional hip joint. In severe cases, in which a congruent joint cannot be achieved, other options are necessary in order to improve functionality and prevent early osteoarthritis. Therefore, we analysed the clinical and radiologic outcome of 28 patients after valgus osteotomy of the proximal femur (VOF). We examined the range of hip motion, functionality and health-related quality of life (HRQoL) via modified Harris Hip Score (mHHS) and Kidscreen-10. Radiographic analysis contained quantitative and qualitative measurements of hip morphology. In particular, we correlated the results with the change of the pelvic-femoral angle (PFA). PFA was defined as the angle between the anatomical diaphyseal line of the femur and a vertical line through the pelvis. The mean follow-up was 5.5 years. Patients showed high mHHS and good HRQoL postoperatively. An increase in ROM with an improvement of 30.5° abduction and 10.3° internal rotation was evident. PFA correlated with adduction contracture and improved significantly after surgery. In consideration of careful patient selection, VOF showed a positive effect on ROM, pain, HRQoL, radiographic congruence and outcome. We identified the age at surgery and an increasing adduction contracture-objectified by a decreased PFA-as a prognostic factor.


Assuntos
Besouros , Contratura , Doença de Legg-Calve-Perthes , Humanos , Animais , Doença de Legg-Calve-Perthes/diagnóstico por imagem , Doença de Legg-Calve-Perthes/cirurgia , Qualidade de Vida , Resultado do Tratamento , Radiografia , Fêmur/diagnóstico por imagem , Fêmur/cirurgia , Osteotomia/métodos , Estudos Retrospectivos
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