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1.
Urol Oncol ; 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38981801

RESUMEN

INTRODUCTION: Clear cell Renal Cell Carcinoma (ccRCC) has a poor prognosis once metastatic. However, certain metastatic sites have been reported to have a different impact on the patient prognosis. For example, patients with pancreatic metastases have a much more favorable prognosis than those with metastases to other organs. The biological basis for this observation remains poorly understood. The aim of this study was to characterize the immune landscape of pancreatic metastases and the corresponding primary tumors in order to identify possible immunological features that correlate with disease biology. PATIENTS AND METHODS: A detailed assessment of immune cell populations was performed using a total of 1,700 microscopic images from ccRCCs from 11 patients, their corresponding pancreatic metastases and ccRCCs from 10 patients without pancreatic metastases. Tumor specimens were stained for CD45, CD8, CD163 and FOXP3 and the densities of the respective immune cells were assessed semiquantitatively in the intratumoral and extratumoral compartment. Multispectral imaging was performed in selected tumors. RESULTS: We found that pancreatic metastases show the lowest intratumoral infiltration with CD8+ cytotoxic T lymphocytes of all tumor specimens analyzed. The frequency of CD8+ lymphocytes was on 1.9 fold lower in pancreatic metastases (median density 8.3 cells per field of view [FOV] = 1.23 mm2) when compared to the corresponding primary tumor (15.6 cells per FOV, P = 0.0002) and more than 3-fold lower when compared to ccRCCs without pancreatic metastases (27.2 cells per FOV, P = 0.0012). There was also a significantly reduced intratumoral infiltration with immunosuppressive FOXP3+ lymphocytes in pancreatic metastases (2.6 cells per FOV, P = 0.009) and corresponding primary tumors (2 cells per FOV, P = 0.028) when compared to ccRCCs without pancreatic metastases (5.6 cells per FOV). CONCLUSIONS: In this proof-of-concept study, we show that pancreatic metastases of ccRCC present with unique immunological features including a low intratumoral density of CD8+ and FOXP3+ lymphocytes. The low counts of CD8+ and FOXP3+ lymphocytes may reflect less aggressive features of ccRCC with pancreatic metastasis that may result in a more favorable patient prognosis.

2.
Cancers (Basel) ; 15(20)2023 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-37894418

RESUMEN

Clear cell renal cell carcinoma (ccRCC) is characterized by a high degree of intratumoral heterogeneity (ITH). Besides genomic ITH, there is considerable functional ITH, which encompasses spatial niches with distinct proliferative and signaling activities. The full extent of functional spatial heterogeneity in ccRCC is incompletely understood. In the present study, a total of 17 ccRCC tissue specimens from different sites (primary tumor, n = 11; local recurrence, n = 1; distant metastasis, n = 5) were analyzed using digital spatial profiling (DSP) of protein expression. A total of 128 regions of interest from the tumor periphery and tumor center were analyzed for the expression of 46 proteins, comprising three major signaling pathways as well as immune cell markers. Results were correlated to clinico-pathological variables. The differential expression of granzyme B was validated using conventional immunohistochemistry and was correlated to the cancer-specific patient survival. We found that a total of 37 proteins were differentially expressed between the tumor periphery and tumor center. Thirty-five of the proteins were upregulated in the tumor periphery compared to the center. These included proteins involved in cell proliferation, MAPK and PI3K/AKT signaling, apoptosis regulation, epithelial-to-mesenchymal transition, as well as immune cell markers. Among the most significantly upregulated proteins in the tumor periphery was granzyme B. Granzyme B upregulation in the tumor periphery correlated with a significantly reduced cancer-specific patient survival. In conclusion, this study highlights the unique cellular contexture of the tumor periphery in ccRCC. The correlation between granzyme B upregulation in the tumor periphery and patient survival suggests local selection pressure for aggressive tumor growth and disease progression. Our results underscore the potential of spatial biology for biomarker discovery in ccRCC and cancer in general.

3.
Sci Rep ; 13(1): 3897, 2023 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-36890210

RESUMEN

We have grown [Formula: see text]Th:CaF[Formula: see text] and [Formula: see text]Th:CaF[Formula: see text] single crystals for investigations on the VUV laser-accessible first nuclear excited state of [Formula: see text]Th, with the aim of building a solid-state nuclear clock. To reach high doping concentrations despite the extreme scarcity (and radioactivity) of [Formula: see text]Th, we have scaled down the crystal volume by a factor 100 compared to established commercial or scientific growth processes. We use the vertical gradient freeze method on 3.2 mm diameter seed single crystals with a 2 mm drilled pocket, filled with a co-precipitated CaF[Formula: see text]:ThF[Formula: see text]:PbF[Formula: see text] powder in order to grow single crystals. Concentrations of [Formula: see text] cm[Formula: see text] have been realized with [Formula: see text]Th with good (> 10%) VUV transmission. However, the intrinsic radioactivity of [Formula: see text]Th drives radio-induced dissociation during growth and radiation damage after solidification. Both lead to a degradation of VUV transmission, currently limiting the [Formula: see text]Th concentration to [Formula: see text] cm[Formula: see text].

4.
Cancer Immunol Immunother ; 72(6): 1603-1618, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36562826

RESUMEN

Clear cell renal cell carcinoma (ccRCC) is an immunologically vulnerable tumor entity, and immune checkpoint inhibitors are now widely used to treat patients with advanced disease. Whether and to what extent immune responses in ccRCC are shaped by genetic alterations, however, is only beginning to emerge. In this proof-of-concept study, we performed a detailed correlative analysis of the mutational and immunological landscapes in a series of 23 consecutive kidney cancer patients. We discovered that a high infiltration with CD8 + T cells was not dependent on the number of driver mutations but rather on the presence of specific mutational events, namely pathogenic mutations in PTEN or BAP1. This observation encouraged us to compare mechanisms of T cell suppression in the context of four different genetic patterns, i.e., the presence of multiple drivers, a PTEN or BAP1 mutation, or the absence of detectable driver mutations. We found that ccRCCs harboring a PTEN or BAP1 mutation showed the lowest level of Granzyme B positive tumor-infiltrating lymphocytes (TILs). A multiplex immunofluorescence analysis revealed a significant number of CD8 + TILs in the vicinity of CD68 + macrophages/monocytes in the context of a BAP1 mutation but not in the context of a PTEN mutation. In line with this finding, direct interactions between CD8 + TILs and CD163 + M2-polarized macrophages were found in BAP1-mutated ccRCC but not in tumors with other mutational patterns. While an absence of driver mutations was associated with more CD8 + TILs in the vicinity of FOXP3 + Tregs and CD68 + monocytes/macrophages, the presence of multiple driver mutations was, to our surprise, not found to be strongly associated with immunosuppressive mechanisms. Our results highlight the role of genetic alterations in shaping the immunological landscape of ccRCC. We discovered a remarkable heterogeneity of mechanisms that can lead to T cell suppression, which supports the need for personalized immune oncological approaches.


Asunto(s)
Carcinoma de Células Renales , Neoplasias Renales , Humanos , Carcinoma de Células Renales/patología , Proteínas de Unión al ADN/genética , Neoplasias Renales/patología , Factores de Transcripción/genética , Mutación , Pronóstico , Proteínas Supresoras de Tumor/genética , Ubiquitina Tiolesterasa/genética , Fosfohidrolasa PTEN/genética
5.
Brain Res Bull ; 192: 21-35, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36336143

RESUMEN

Directed outgrowth of axons is fundamental for the establishment of neuronal networks. Axon outgrowth is guided by growth cones, highly motile structures enriched in filamentous actin (F-actin) located at the axons' distal tips. Growth cones exploit F-actin-based protrusions to scan the environment for guidance cues, and they contain the sensory apparatus to translate guidance cue information into intracellular signaling cascades. These cascades act upstream of actin-binding proteins (ABP) and thereby control assembly and disassembly of F-actin. Spatiotemporally controlled F-actin dis-/assembly in growth cones steers the axon towards attractants and away from repellents, and it thereby navigates the axon through the developing nervous system. Hence, ABP that control F-actin dynamics emerged as critical regulators of neuronal network formation. In the present review article, we will summarize and discuss current knowledge of the mechanisms that control remodeling of the actin cytoskeleton in growth cones, focusing on recent progress in the field. Further, we will introduce tools and techniques that allow to study actin regulatory mechanism in growth cones.


Asunto(s)
Actinas , Conos de Crecimiento , Conos de Crecimiento/metabolismo , Actinas/metabolismo , Citoesqueleto de Actina/metabolismo , Axones/metabolismo , Proteínas de Microfilamentos/metabolismo
6.
Pharmaceutics ; 14(5)2022 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-35631635

RESUMEN

In recent years, the colon has become a hot topic in biopharmaceutical research as several in vitro models of the human colon have been presented. A major focus is on the characterization of the microbiota and its capabilities. The aim of the present study was to further develop the MimiCol, preserving its properties and accelerating data acquisition. Emphasis was placed on the simplicity of its design and easy scalability. To prove the viability of the concept, degradation of sulfasalazine was investigated, and the bacterial composition during the experiment was assessed by 16S rRNA sequencing. The transfer of the experimental conditions to the new model was successful. Commercially available components were implemented in the setup. The model MimiCol3 represented the colon ascendens satisfactorily in its properties regarding volume, pH value, and redox potential. 16S rRNA sequencing led to further insights into the bacterial composition in the vessels. Degradation of sulfasalazine was in good agreement with in vivo data. The new model of the colon ascendens MimiCol3 enabled us to collect more reliable data, as three experiments were conducted simultaneously under the same conditions.

7.
Front Oncol ; 12: 889686, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35619925

RESUMEN

Renal cell carcinoma (RCC) is among the most lethal urological malignancies once metastatic. The introduction of immune checkpoint inhibitors has revolutionized the therapeutic landscape of metastatic RCC, nevertheless, a significant proportion of patients will experience disease progression. Novel treatment options are therefore still needed and in vitro and in vivo model systems are crucial to ultimately improve disease control. At the same time, RCC is characterized by a number of molecular and functional peculiarities that have the potential to limit the utility of pre-clinical model systems. This includes not only the well-known genomic intratumoral heterogeneity (ITH) of RCC but also a remarkable functional ITH that can be shaped by influences of the tumor microenvironment. Importantly, RCC is among the tumor entities, in which a high number of intratumoral cytotoxic T cells is associated with a poor prognosis. In fact, many of these T cells are exhausted, which represents a major challenge for modeling tumor-immune cell interactions. Lastly, pre-clinical drug development commonly relies on using phenotypic screening of 2D or 3D RCC cell culture models, however, the problem of "reverse engineering" can prevent the identification of the precise mode of action of drug candidates thus impeding their translation to the clinic. In conclusion, a holistic approach to model the complex "ecosystem RCC" will likely require not only a combination of model systems but also an integration of concepts and methods using artificial intelligence to further improve pre-clinical drug discovery.

8.
Sci Rep ; 12(1): 8275, 2022 05 18.
Artículo en Inglés | MEDLINE | ID: mdl-35585158

RESUMEN

Although KIT-mutant GISTs can be effectively treated with tyrosine kinase inhibitors (TKIs), many patients develop resistance to imatinib mesylate (IM) as well as the FDA-approved later-line agents sunitinib, regorafenib and ripretinib. Resistance mechanisms mainly involve secondary mutations in the KIT receptor tyrosine kinase gene indicating continued dependency on the KIT signaling pathway. The fact that the type of secondary mutation confers either sensitivity or resistance towards TKIs and the notion that secondary mutations exhibit intra- and intertumoral heterogeneity complicates the optimal choice of treatment in the imatinib-resistant setting. Therefore, new strategies that target KIT independently of its underlying mutations are urgently needed. Homoharringtonine (HHT) is a first-in-class inhibitor of protein biosynthesis and is FDA-approved for the treatment of chronic myeloid leukemia (CML) that is resistant to at least two TKIs. HHT has also shown activity in KIT-mutant mastocytosis models, which are intrinsically resistant to imatinib and most other TKIs. We hypothesized that HHT could be effective in GIST through downregulation of KIT expression and subsequent decrease of KIT activation and downstream signaling. Testing several GIST cell line models, HHT led to a significant reduction in nascent protein synthesis and was highly effective in the nanomolar range in IM-sensitive and IM-resistant GIST cell lines. HHT treatment resulted in a rapid and complete abolishment of KIT expression and activation, while KIT mRNA levels were minimally affected. The response to HHT involved induction of apoptosis as well as cell cycle arrest. The antitumor activity of HHT was confirmed in a GIST xenograft model. Taken together, inhibition of protein biosynthesis is a promising strategy to overcome TKI resistance in GIST.


Asunto(s)
Antineoplásicos , Neoplasias Gastrointestinales , Tumores del Estroma Gastrointestinal , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Resistencia a Antineoplásicos/genética , Neoplasias Gastrointestinales/tratamiento farmacológico , Neoplasias Gastrointestinales/genética , Neoplasias Gastrointestinales/patología , Tumores del Estroma Gastrointestinal/tratamiento farmacológico , Tumores del Estroma Gastrointestinal/genética , Tumores del Estroma Gastrointestinal/patología , Homoharringtonina/farmacología , Humanos , Mesilato de Imatinib/farmacología , Mesilato de Imatinib/uso terapéutico , Mutación , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/uso terapéutico , Proteínas Proto-Oncogénicas c-kit/metabolismo
9.
Acta Paediatr ; 110(12): 3315-3321, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34525232

RESUMEN

AIM: It can be challenging to distinguish COVID-19 in children from other common infections. We set out to determine the rate at which children consulting a primary care paediatrician with an acute infection are infected with SARS-CoV-2 and to compare distinct findings. METHOD: In seven out-patient clinics, children aged 0-13 years with any new respiratory or gastrointestinal symptoms and presumed infection were invited to be tested for SARS-CoV-2. Factors that were correlated with testing positive were determined. Samples were collected from 25 January 2021 to 01 April 2021. RESULTS: Seven hundred and eighty-three children participated in the study (median age 3 years and 0 months, range 1 month to 12 years and 11 months). Three hundred and fifty-eight were female (45.7%). SARS-CoV-2 RNA was detected in 19 (2.4%). The most common symptoms in children with as well as without detectable SARS-CoV-2 RNA were rhinitis, fever and cough. Known recent exposure to a case of COVID-19 was significantly correlated with testing positive, but symptoms or clinical findings were not. CONCLUSION: COVID-19 among the children with symptoms of an acute infection was uncommon, and the clinical presentation did not differ significantly between children with and without evidence of an infection with SARS-CoV-2.


Asunto(s)
COVID-19 , Niño , Femenino , Fiebre , Humanos , Lactante , Atención Primaria de Salud , ARN Viral , SARS-CoV-2
10.
J Control Release ; 338: 105-118, 2021 10 10.
Artículo en Inglés | MEDLINE | ID: mdl-34416321

RESUMEN

More than 50 years ago, the first gastroretentive dosage forms came up. Since then, no practical and at the same time reliable gastroretentive system is available on market. A major obstacle in the development of novel gastroretentive systems is the lack of proper predictive test methods. In the present work, we aimed at developing and fully characterizing an expandable gastroretentive system containing furosemide as model drug. On the one hand, we used well-established in vitro tests for drug dissolution and gastroretentive properties (paddle apparatus, swelling characteristics). On the other hand, we used two novel models (dissolution stress test device, mechanical antrum model) to assess these properties under biorelevant conditions. Moreover, we performed an in vivo study under fed and fasted conditions that combined blood sampling and a high-resolution imaging technique (magnetic marker monitoring) to determine gastrointestinal location with the assessment of a pharmacodynamic endpoint (urinary sodium excretion). In vitro dissolution tests confirmed prolonged drug release over more than 8 h independent from pH and with slight pressure sensitivity. Swelling studies indicated good swelling behavior within 4 h along with medium gastroretentive properties as determined with the mechanical antrum model. In vivo imaging showed prolonged gastric residence time after fed compared to fasted administration (481 min vs 38 min). Comparison of geometric means of AUCo-tlast of the model drug confirmed this observation with 10 times higher value after fed administration. Urinary excretion of sodium well reflected the increased sodium-reuptake inhibition due to higher furosemide exposure under fed conditions. However, the poor performance after fasted intake of the system is in line with data from several other gastroretentive formulations. The present study highlighted the value of novel test methods during the development of gastroretentive formulations. Yet, a system with reproducible gastroretentive properties especially under fasted conditions has to be designed.


Asunto(s)
Furosemida , Estómago , Liberación de Fármacos , Ayuno , Solubilidad , Estómago/diagnóstico por imagen
11.
Cells ; 10(6)2021 06 17.
Artículo en Inglés | MEDLINE | ID: mdl-34204261

RESUMEN

Cyclase-associated proteins (CAPs) are evolutionary-conserved actin-binding proteins with crucial functions in regulating actin dynamics, the spatiotemporally controlled assembly and disassembly of actin filaments (F-actin). Mammals possess two family members (CAP1 and CAP2) with different expression patterns. Unlike most other tissues, both CAPs are expressed in the brain and present in hippocampal neurons. We recently reported crucial roles for CAP1 in growth cone function, neuron differentiation, and neuron connectivity in the mouse brain. Instead, CAP2 controls dendritic spine morphology and synaptic plasticity, and its dysregulation contributes to Alzheimer's disease pathology. These findings are in line with a model in which CAP1 controls important aspects during neuron differentiation, while CAP2 is relevant in differentiated neurons. We here report CAP2 expression during neuron differentiation and its enrichment in growth cones. We therefore hypothesized that CAP2 is relevant not only in excitatory synapses, but also in differentiating neurons. However, CAP2 inactivation neither impaired growth cone morphology and motility nor neuron differentiation. Moreover, CAP2 mutant mice did not display any obvious changes in brain anatomy. Hence, differently from CAP1, CAP2 was dispensable for neuron differentiation and brain development. Interestingly, overexpression of CAP2 rescued not only growth cone size in CAP1-deficient neurons, but also their morphology and differentiation. Our data provide evidence for functional redundancy of CAP1 and CAP2 in differentiating neurons, and they suggest compensatory mechanisms in single mutant neurons.


Asunto(s)
Proteínas Portadoras/metabolismo , Diferenciación Celular/fisiología , Neuronas/metabolismo , Animales , Ratones , Neurogénesis/fisiología
12.
Sci Rep ; 11(1): 14144, 2021 07 08.
Artículo en Inglés | MEDLINE | ID: mdl-34239015

RESUMEN

We report on a multi-technique analysis using publicly available data for investigating the huge, accidental explosion that struck the city of Beirut, Lebanon, on August 4, 2020. Its devastating shock wave led to thousands of injured with more than two hundred fatalities and caused immense damage to buildings and infrastructure. Our combined analysis of seismological, hydroacoustic, infrasonic and radar remote sensing data allows us to characterize the source as well as to estimate the explosive yield. The latter is determined within 0.13 to 2 kt TNT (kilotons of trinitrotoluene). This range is plausible given the reported 2.75 kt of ammonium nitrate as explosive source. As there are strict limitations for an on-site analysis of this catastrophic explosion, our presented approach based on data from open accessible global station networks and satellite missions is of high scientific and social relevance that furthermore is transferable to other explosions.

13.
Cell Rep ; 35(11): 109242, 2021 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-34133935

RESUMEN

Figure-ground segregation, the brain's ability to group related features into stable perceptual entities, is crucial for auditory perception in noisy environments. The neuronal mechanisms for this process are poorly understood in the auditory system. Here, we report figure-ground modulation of multi-unit activity (MUA) in the primary and non-primary auditory cortex of rhesus macaques. Across both regions, MUA increases upon presentation of auditory figures, which consist of coherent chord sequences. We show increased activity even in the absence of any perceptual decision, suggesting that neural mechanisms for perceptual grouping are, to some extent, independent of behavioral demands. Furthermore, we demonstrate differences in figure encoding between more anterior and more posterior regions; perceptual saliency is represented in anterior cortical fields only. Our results suggest an encoding of auditory figures from the earliest cortical stages by a rate code.


Asunto(s)
Corteza Auditiva/fisiología , Neuronas/fisiología , Estimulación Acústica , Animales , Percepción Auditiva/fisiología , Femenino , Macaca mulatta , Masculino , Actividad Motora/fisiología , Procesos Estocásticos
14.
eNeuro ; 8(3)2021.
Artículo en Inglés | MEDLINE | ID: mdl-33958372

RESUMEN

Neuron differentiation includes formation and outgrowth of neurites that differentiate into axons or dendrites. Directed neurite outgrowth is controlled by growth cones that protrude and retract actin-rich structures to sense environmental cues. These cues control local actin filament dynamics, steer growth cones toward attractants and away from repellents, and navigate neurites through the developing brain. Rodent hippocampal neurons are widely used to study the mechanisms underlying neuron differentiation. Genetic manipulation of isolated neurons including gene inactivation or reporter gene expression can be achieved by classical transfections methods, but these methods are restricted to neurons cultured for several days, after neurite formation or outgrowth. Instead, electroporation allows gene manipulation before seeding. However, reporter gene expression usually takes up to 24 h, and time course of gene inactivation depends on the half live of the targeted mRNA and gene product. Hence, these methods do not allow to study early aspects of neuron differentiation. In the present study, we provide a detailed protocol in which we combined electroporation-based gene manipulation of mouse hippocampal neurons before initial seeding with a replating step after 2 d in vitro (DIV) that resets neurons into an undifferentiated stage. By categorizing neurons according to their differentiation stage, thorough morphometric analyses, live imaging of actin dynamics in growth cones as well as guidance cue-mediated growth cone morphologic changes, we demonstrate that differentiation and function of replated neurons did not differ from non-replated neurons. In summary, we provide a protocol that allows to thoroughly characterize differentiation of mouse primary hippocampal neurons.


Asunto(s)
Neuritas , Neuronas , Animales , Células Cultivadas , Conos de Crecimiento , Ratones , Neurogénesis
15.
Prog Neurobiol ; 202: 102050, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33845164

RESUMEN

Neuron connectivity depends on growth cones that navigate axons through the developing brain. Growth cones protrude and retract actin-rich structures to sense guidance cues. These cues control local actin dynamics and steer growth cones towards attractants and away from repellents, thereby directing axon outgrowth. Hence, actin binding proteins (ABPs) moved into the focus as critical regulators of neuron connectivity. We found cyclase-associated protein 1 (CAP1), an ABP with unknown brain function, abundant in growth cones. Super-resolution microscopy and live cell imaging combined with pharmacological approaches on hippocampal neurons from gene-targeted mice revealed a crucial role for CAP1 in actin dynamics that is critical for growth cone morphology and function. Growth cone defects in CAP1 knockout (KO) neurons compromised neuron differentiation and was associated with impaired neuron connectivity in CAP1-KO brains. Mechanistically, by rescue experiments in double KO neurons lacking CAP1 and the key actin regulator cofilin1, we demonstrated that CAP1 was essential for cofilin1 function in growth cone actin dynamics and morphology and vice versa. Together, we identified CAP1 as a novel actin regulator in growth cones that was relevant for neuron connectivity, and we demonstrated functional interdependence of CAP1 and cofilin1 in neuronal actin dynamics and growth cone function.


Asunto(s)
Actinas , Conos de Crecimiento , Animales , Proteínas de Ciclo Celular , Proteínas del Citoesqueleto , Estado Funcional , Humanos , Ratones , Neurogénesis , Neuronas
16.
Neuroimage ; 230: 117778, 2021 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-33497775

RESUMEN

Information from Magnetic Resonance Imaging (MRI) is useful for diagnosis and treatment management of human neurological patients. MRI monitoring might also prove useful for non-human animals involved in neuroscience research provided that MRI is available and feasible and that there are no MRI contra-indications precluding scanning. However, MRI monitoring is not established in macaques and a resource is urgently needed that could grow with scientific community contributions. Here we show the utility and potential benefits of MRI-based monitoring in a few diverse cases with macaque monkeys. We also establish a PRIMatE MRI Monitoring (PRIME-MRM) resource within the PRIMatE Data Exchange (PRIME-DE) and quantitatively compare the cases to normative information drawn from MRI data from typical macaques in PRIME-DE. In the cases, the monkeys presented with no or mild/moderate clinical signs, were well otherwise and MRI scanning did not present a significant increase in welfare impact. Therefore, they were identified as suitable candidates for clinical investigation, MRI-based monitoring and treatment. For each case, we show MRI quantification of internal controls in relation to treatment steps and comparisons with normative data in typical monkeys drawn from PRIME-DE. We found that MRI assists in precise and early diagnosis of cerebral events and can be useful for visualising, treating and quantifying treatment response. The scientific community could now grow the PRIME-MRM resource with other cases and larger samples to further assess and increase the evidence base on the benefits of MRI monitoring of primates, complementing the animals' clinical monitoring and treatment regime.


Asunto(s)
Encéfalo/diagnóstico por imagen , Análisis de Datos , Imagen por Resonancia Magnética/métodos , Enfermedades del Sistema Nervioso/diagnóstico por imagen , Animales , Estudios de Casos y Controles , Enfermedades Desmielinizantes/diagnóstico por imagen , Enfermedades Desmielinizantes/terapia , Infecciones/diagnóstico por imagen , Infecciones/terapia , Macaca mulatta , Masculino , Debilidad Muscular/diagnóstico por imagen , Debilidad Muscular/terapia , Enfermedades del Sistema Nervioso/terapia
17.
J Pharm Sci ; 110(3): 1302-1309, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33253724

RESUMEN

Infections with Helicobacter pylori are a global challenge. Currently, H. pylori infections are treated systemically, but the eradication rates of the different therapy regimens are declining due to the growing number of bacterial strains resistant to major antibiotics. Here, we present a strategy for the local eradication of H. pylori by the use of Penicillin G sodium (PGS). In vitro experiments revealed that PGS shows high antibiotic activity against resistant strains of Helicobacter pylori with a minimum inhibitory concentration (MIC) of 0.125 µg/ml. In order to provide luminal concentrations above the MIC for longer periods of time, an extended release tablet was developed. Alkalizers were included to prevent acidic degradation of PGS within the tablet matrix. Out of the tested alkalizers MgO, l-Lysine, NaHCO3, and Na2CO3 NaHCO3 provided the strongest rise in pH inside the hydrated matrix when tested in simulated gastric fluid. Better PGS stability can mainly reasoned from that, addition of MgO resulted in high pH values within the matrix, causing basic degradation of PGS. This work is a first step towards the use of extended release tablets containing PGS for the local treatment of H. pylori as a safe and cost-effective alternative to common systemic treatment regimens.


Asunto(s)
Infecciones por Helicobacter , Helicobacter pylori , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Infecciones por Helicobacter/tratamiento farmacológico , Humanos , Pruebas de Sensibilidad Microbiana
18.
Eur J Pharm Sci ; 156: 105627, 2021 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-33122007

RESUMEN

Within preclinical research, the pig has become an important model in regulatory toxicology and pharmacokinetics, to assess oral dosage forms and to compare different formulation strategies. In addition, there are emerging application of the pig model to asses clinical dosing conditions in the fasted and fed state. In this study, the gastrointestinal transit conditions in male landrace pigs were studied with a telemetric motility capsule under fasted and postprandial conditions. The whole gut transit time (WGTT) was determined by administering a SmartPill® capsule to four landrace pigs, under both fasted and fed state conditions in a cross-over study design. Overall, this study found that small intestinal transit in landrace pigs ranged from 2.3 - 4.0 h, and was broadly similar to reported human estimates and was not affected by the intake conditions. Gastric emptying was highly variable and prolonged in landrace pigs ranging from 20 - 233 h and up to 264 h in one specific case. Under dynamic conditions pigs have a low gastric pH comparable to humans, however a high variability under fasted conditions could be observed. The comparison of the data from this study with a recent similar study in beagle dogs revealed major differences between gastric maximum pressures observed in landrace pigs and dogs. In the porcine stomach maximum pressures of up to 402 mbar were observed, which are comparable to reported human data. Intestinal maximum pressures in landrace pigs were in the same range as in humans. Overall, the study provides new insights of gastrointestinal conditions in landrace pigs, which can lead to more accurate interpretation of in vivo results obtained of pharmacokinetic studies in preclinical models. While small intestinal transit conditions, GI pH and pressures were similar to humans, the prolonged gastric emptying observed in pigs need to be considered in assessing the suitability of the pig model for assessing in vivo performance of large non-disintegrated oral drug products.


Asunto(s)
Vaciamiento Gástrico , Tránsito Gastrointestinal , Animales , Estudios Cruzados , Digestión , Perros , Motilidad Gastrointestinal , Masculino , Porcinos , Telemetría
19.
J Geophys Res Solid Earth ; 125(7): e2019JB019102, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32999803

RESUMEN

Stripe-like patterns of surface wave arrival angle deviations have been observed by several seismological studies around the world, but this phenomenon has not been explained so far. Here we test the hypothesis that systematic arrival angle deviations observed at the AlpArray broadband seismic network in Europe are interference patterns caused by diffraction of surface waves at single small-scaled velocity anomalies. We use the observed pattern of Rayleigh waves from two earthquakes under the Southern Atlantic Ocean, and we fit this pattern with theoretical arrival angles derived by a simple modeling approach describing the interaction of a seismic wavefield with small anomalies. A grid search inversion scheme is implemented, which indicates that the anomaly is located in Central Africa, with its head under Cameroon. Moreover, the inversion enables the characterization of the anomaly: The anomaly is inferred to be between 320 and 420 km wide, matching in length the 2,500 km long upper mantle low-velocity region under the volcano-capped swells of the Cameroon volcanic line. We show that this approach can be generally used for studying the upper mantle anomalies worldwide.

20.
J Anim Physiol Anim Nutr (Berl) ; 104(2): 462-469, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31943416

RESUMEN

The aim of the study was to determine the abomasal emptying rate (AER) of calves suffering from naturally occurring diarrhoea compared with that of healthy calves. Furthermore, the effects of an oral rehydration solution (ORS) mixed into milk replacer on the AER were determined. Acetaminophen absorption test (APAT) was performed to estimate the AER. Sixty Holstein-Frisian calves (age < 14 days) were included in the study and divided into groups as follows: healthy calves (H; n = 16), healthy calves fed with ORS (HORS; n = 14), diarrhoeic calves (D; n = 15) and diarrhoeic calves fed with ORS (DORS; n = 15). For the APAT, the calves were fed 2 L of milk replacer containing 50 mg acetaminophen (AP)/kg body weight. Venous blood samples were collected before and after milk replacer and AP intake in 30-60 min intervals for 12 hr. During the APAT, no significant differences in median maximum acetaminophen concentration (Cmax ) were observed among all groups. Time to reach maximum acetaminophen concentration (Tmax ) in DORS (median 390 min, 25/75 quartiles: 300/480 min) was significantly higher compared with that in H (median: 270 min 25/75 quartiles: 210/315 min) and HORS (median: 300 min (25/75 quartiles: 240/360 min). Non-linear regression revealed that the calculated abomasal half-life (AP t1/2 ) tended to be delayed in DORS (median: 652 min, 25/75 quartiles: 445/795 min, p = .10). The area under the AP curve values (AUC) from 0 to 120 min and 0 to 240 min of the observation period were significantly higher in H than D and DORS. In conclusion, significant differences in the AER indices reflected delayed abomasal emptying in diarrhoeic calves. Furthermore, the hypertonic ORS tended to have an additive delaying impact on the AER, which needs attention for the feeding management of diarrhoeic calves.


Asunto(s)
Abomaso/efectos de los fármacos , Enfermedades de los Bovinos/terapia , Diarrea/veterinaria , Vaciamiento Gástrico , Soluciones para Rehidratación/administración & dosificación , Acetaminofén/toxicidad , Animales , Animales Lactantes , Bovinos , Diarrea/inducido químicamente , Diarrea/terapia , Sustitutos de la Leche
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