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1.
Development ; 149(21)2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-36278895

RESUMO

Oocyte maturation and early embryo development occur in vertebrates in the near absence of transcription. Thus, sexual reproduction of vertebrates critically depends on the timely translation of mRNAs already stockpiled in the oocyte. Yet how translational activation of specific mRNAs is temporally coordinated is still incompletely understood. Here, we elucidate the function of Zar1l, a yet uncharacterized member of the Zar RNA-binding protein family, in Xenopus oocytes. Employing TRIM-Away, we demonstrate that loss of Zar1l accelerates hormone-induced meiotic resumption of Xenopus oocytes due to premature accumulation of the M-phase-promoting kinase cMos. We show that Zar1l is a constituent of a large ribonucleoparticle containing the translation repressor 4E-T and the central polyadenylation regulator CPEB1, and that it binds directly to the cMos mRNA. Partial, hormone-induced degradation of Zar1l liberates 4E-T from CPEB1, which weakens translational repression of mRNAs encoding cMos and likely additional M-phase-promoting factors. Thus, our study provides fundamental insights into the mechanisms that ensure temporally regulated translation of key cell cycle regulators during oocyte maturation, which is essential for sexual reproductivity.


Assuntos
Meiose , Oócitos , Animais , Xenopus laevis/genética , Xenopus laevis/metabolismo , Oócitos/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Hormônios/metabolismo , Proteínas de Xenopus/genética , Proteínas de Xenopus/metabolismo , Biossíntese de Proteínas
2.
Epilepsia ; 65(1): 115-126, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37846648

RESUMO

OBJECTIVE: The aim was to investigate the monitoring, interventions, and occurrence of critical, potentially life-threatening incidents in patients with Dravet syndrome (DS) and caregivers' knowledge about sudden unexpected death in epilepsy (SUDEP). METHODS: This multicenter, cross-sectional study of patients with DS and their caregivers in Germany consisted of a questionnaire and prospective diary querying the disease characteristics and demographic data of patients and caregivers. RESULTS: Our analysis included 108 questionnaires and 82 diaries. Patients with DS were 49.1% male (n = 53), with a mean age of 13.5 (SD ± 10.0 years) and primary caregivers were 92.6% (n = 100) female, with a mean age of 44.7 (SD ± 10.6 years). Monitoring devices were used regularly by 75.9% (n = 82) of caregivers, and most monitored daily/nightly. Frequently used devices were pulse oximeters (64.6%), baby monitors (64.6%), thermometers (24.1%), and Epi-Care (26.8%). Younger caregiver and patient age and history of status epilepticus were associated with increased use of monitoring, and 81% of monitor users reported having avoided a critical incident with nocturnal monitoring. The need for resuscitation due to cardiac or respiratory arrest was reported by 22 caregivers (20.4%), and most cases (72.7%) were associated with a seizure. Caregivers reported frequently performing interventions at night, including oropharyngeal suction, oxygenation, personal hygiene, and change of body position. Most caregivers were well informed about SUDEP (n = 102; 94%) and monitored for a lateral or supine body position; however, only 39.8% reported receiving resuscitation training, whereas 52.8% (n = 57) knew what to do in case the child's breathing or heart activity failed. SIGNIFICANCE: Critical incidents and the need for resuscitation are reported frequently by caregivers and may be related to high mortality and SUDEP rates in DS. Resuscitation training is welcomed by caregivers and should be continuously provided. Oxygen monitoring devices are frequently used and considered useful by caregivers.


Assuntos
Epilepsias Mioclônicas , Morte Súbita Inesperada na Epilepsia , Criança , Humanos , Masculino , Feminino , Adolescente , Adulto , Cuidadores , Estudos Prospectivos , Estudos Transversais , Morte Súbita/epidemiologia , Morte Súbita/etiologia , Epilepsias Mioclônicas/terapia , Alemanha/epidemiologia
3.
Int J Mol Sci ; 25(5)2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38474010

RESUMO

Hemophagocytic lymphohistiocytosis (HLH) is a rare but in most cases life-threatening immune-mediated disease of the hematopoietic system frequently associated with hematologic neoplasms. Here, we report on a case in which we detected a novel constellation of two missense variants affecting the PRF1 gene, leading to de novo primary HLH. Diagnostics included a comprehensive clinical work-up and standard methods of hematopathology as well as extended molecular genomics based on polymerase chain reaction (PCR) reactions and the calculation of three-dimensional molecule reconstructions of PRF1. Subsequently, a comprehensive review of the literature was performed, which showed that this compound heterozygosity has not been previously described. The patient was a 20-year-old female. Molecular diagnostics revealed two heterozygous missense variants in the PRF1 gene (A91V and R104C) on exon 2. Apart from the finding of two inconclusive genetic variants, all clinical criteria defined by the HLH study group of Histiocyte Society were met at initial presentation. The final diagnosis was made in cooperation with the Consortium of German HLH-reference centers. Here, chemotherapy did not lead to sufficient sustained disease control. Therefore, the decision for allogenic hematopoietic stem cell transplantation (alloHSCT) was made. Hitherto, the duration of response was 6 months. Due to severe and unmanageable hepatic graft-versus-host disease (GvHD), the patient died. We report on a novel constellation of a compound heterozygosity containing two missense variants on exon 2 of the PRF1 gene. To the authors' best knowledge, this is the first presentation of a primary HLH case harboring this genomic constellation with late-onset clinical manifestation.


Assuntos
Linfo-Histiocitose Hemofagocítica , Feminino , Humanos , Adulto Jovem , Adulto , Linfo-Histiocitose Hemofagocítica/genética , Perforina/genética , Mutação de Sentido Incorreto , Éxons , Genômica , Mutação
4.
Molecules ; 29(14)2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39064959

RESUMO

The emergence of inflammatory diseases is a heavy burden on modern societies. Cannabis has been used for several millennia to treat inflammatory disorders such as rheumatism or gout. Since the characterization of cannabinoid receptors, CB1 and CB2, the potential of cannabinoid pharmacotherapy in inflammatory conditions has received great interest. Several studies have identified the importance of these receptors in immune cell migration and in the production of inflammatory mediators. As the presence of the CB2 receptor was documented to be more predominant in immune cells, several pharmacological agonists and antagonists have been designed to treat inflammation. To better define the potential of the CB2 receptor, three online databases, PubMed, Google Scholar and clinicaltrial.gov, were searched without language restriction. The full texts of articles presenting data on the endocannabinoid system, the CB2 receptor and its role in modulating inflammation in vitro, in animal models and in the context of clinical trials were reviewed. Finally, we discuss the clinical potential of the latest cannabinoid-based therapies in inflammatory diseases.


Assuntos
Inflamação , Receptor CB2 de Canabinoide , Humanos , Receptor CB2 de Canabinoide/metabolismo , Receptor CB2 de Canabinoide/agonistas , Inflamação/metabolismo , Inflamação/tratamento farmacológico , Animais , Canabinoides/uso terapêutico , Canabinoides/farmacologia , Endocanabinoides/metabolismo , Anti-Inflamatórios/uso terapêutico , Anti-Inflamatórios/farmacologia , Agonistas de Receptores de Canabinoides/farmacologia , Agonistas de Receptores de Canabinoides/uso terapêutico
5.
Angew Chem Int Ed Engl ; 63(20): e202320247, 2024 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-38501674

RESUMO

Protein O-GlcNAcylation is a ubiquitous posttranslational modification of cytosolic and nuclear proteins involved in numerous fundamental regulation processes. Investigation of O-GlcNAcylation by metabolic glycoengineering (MGE) has been carried out for two decades with peracetylated N-acetylglucosamine (GlcNAc) and N-acetylgalactosamine derivatives modified with varying reporter groups. Recently, it has been shown that these derivatives can result in non-specific protein labeling termed S-glyco modification. Here, we report norbornene-modified GlcNAc derivatives with a protected phosphate at the anomeric position and their application in MGE. These derivatives overcome two limitations of previously used O-GlcNAc reporters. They do not lead to detectable S-glyco modification, and they efficiently react in the inverse-electron-demand Diels-Alder (IEDDA) reaction, which can be carried out even within living cells. Using a derivative with an S-acetyl-2-thioethyl-protected phosphate, we demonstrate the protein-specific detection of O-GlcNAcylation of several proteins and the protein-specific imaging of O-GlcNAcylation inside living cells by Förster resonance energy transfer (FRET) visualized by confocal fluorescence lifetime imaging microscopy (FLIM).


Assuntos
Acetilglucosamina , Glicoproteínas , Imagem Molecular , Norbornanos , Processamento de Proteína Pós-Traducional , Glicosilação , Engenharia Metabólica , Norbornanos/química , Acetilglucosamina/análogos & derivados , Acetilglucosamina/química , Transferência Ressonante de Energia de Fluorescência , Glicoproteínas/análise , Humanos , Células HeLa
6.
J Am Chem Soc ; 145(1): 634-644, 2023 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-36571481

RESUMO

Toehold-mediated strand displacement (TMSD) has been used extensively for molecular sensing and computing in DNA-based molecular circuits. As these circuits grow in complexity, sequence similarity between components can lead to cross-talk, causing leak, altered kinetics, or even circuit failure. For small non-biological circuits, such unwanted interactions can be designed against. In environments containing a huge number of sequences, taking all possible interactions into account becomes infeasible. Therefore, a general understanding of the impact of sequence backgrounds on TMSD reactions is of great interest. Here, we investigate the impact of random DNA sequences on TMSD circuits. We begin by studying individual interfering strands and use the obtained data to build machine learning models that estimate kinetics. We then investigate the influence of pools of random strands and find that the kinetics are determined by only a small subpopulation of strongly interacting strands. Consequently, their behavior can be mimicked by a small collection of such strands. The equilibration of the circuit with the background sequences strongly influences this behavior, leading to up to 1 order of magnitude difference in reaction speed. Finally, we compare two established and one novel technique that speed up TMSD reactions in random sequence pools: a three-letter alphabet, protection of toeholds by intramolecular secondary structure, or by an additional blocking strand. While all of these techniques were useful, only the latter can be used without sequence constraints. We expect that our insights will be useful for the construction of TMSD circuits that are robust to molecular noise.


Assuntos
DNA , DNA/química , Cinética
7.
Chemphyschem ; 24(23): e202300231, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37706589

RESUMO

NiOx films on Si(111) were put in contact with oxygen at elevated temperatures. During heating and cooling in oxygen atmosphere Near Ambient Pressure (NAP)-XPS and -XAS and work function (WF) measurements reveal the creation and replenishing of oxygen vacancies in dependence of temperature. Oxygen vacancies manifest themselves as a distinct O1s feature at 528.9 eV on the low binding energy side of the main NiO peak as well as by a distinct deviation of the Ni2p3/2 spectral features from the typical NiO spectra. DFT calculations reveal that the presence of oxygen vacancies leads to a charge redistribution and altered bond lengths of the atoms surrounding the vacancies causing the observed spectral changes. Furthermore, we observed that a broadening of the lowest energy peak in the O K-edge spectra can be attributed to oxygen vacancies. In the presence of oxygen vacancies, the WF is lowered by 0.1 eV.

8.
Brain ; 145(9): 2991-3009, 2022 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-34431999

RESUMO

We report detailed functional analyses and genotype-phenotype correlations in 392 individuals carrying disease-causing variants in SCN8A, encoding the voltage-gated Na+ channel Nav1.6, with the aim of describing clinical phenotypes related to functional effects. Six different clinical subgroups were identified: Group 1, benign familial infantile epilepsy (n = 15, normal cognition, treatable seizures); Group 2, intermediate epilepsy (n = 33, mild intellectual disability, partially pharmaco-responsive); Group 3, developmental and epileptic encephalopathy (n = 177, severe intellectual disability, majority pharmaco-resistant); Group 4, generalized epilepsy (n = 20, mild to moderate intellectual disability, frequently with absence seizures); Group 5, unclassifiable epilepsy (n = 127); and Group 6, neurodevelopmental disorder without epilepsy (n = 20, mild to moderate intellectual disability). Those in Groups 1-3 presented with focal or multifocal seizures (median age of onset: 4 months) and focal epileptiform discharges, whereas the onset of seizures in patients with generalized epilepsy was later (median: 42 months) with generalized epileptiform discharges. We performed functional studies expressing missense variants in ND7/23 neuroblastoma cells and primary neuronal cultures using recombinant tetrodotoxin-insensitive human Nav1.6 channels and whole-cell patch-clamping. Two variants causing developmental and epileptic encephalopathy showed a strong gain-of-function (hyperpolarizing shift of steady-state activation, strongly increased neuronal firing rate) and one variant causing benign familial infantile epilepsy or intermediate epilepsy showed a mild gain-of-function (defective fast inactivation, less increased firing). In contrast, all three variants causing generalized epilepsy induced a loss-of-function (reduced current amplitudes, depolarizing shift of steady-state activation, reduced neuronal firing). Functional effects were known for 170 individuals. All 136 individuals carrying a functionally tested gain-of-function variant had either focal (n = 97, Groups 1-3) or unclassifiable (n = 39) epilepsy, whereas 34 individuals with a loss-of-function variant had either generalized (n = 14), no (n = 11) or unclassifiable (n = 6) epilepsy; only three had developmental and epileptic encephalopathy. Computational modelling in the gain-of-function group revealed a significant correlation between the severity of the electrophysiological and clinical phenotypes. Gain-of-function variant carriers responded significantly better to sodium channel blockers than to other anti-seizure medications, and the same applied for all individuals in Groups 1-3. In conclusion, our data reveal clear genotype-phenotype correlations between age at seizure onset, type of epilepsy and gain- or loss-of-function effects of SCN8A variants. Generalized epilepsy with absence seizures is the main epilepsy phenotype of loss-of-function variant carriers and the extent of the electrophysiological dysfunction of the gain-of-function variants is a main determinant of the severity of the clinical phenotype in focal epilepsies. Our pharmacological data indicate that sodium channel blockers present a treatment option in SCN8A-related focal epilepsy with onset in the first year of life.


Assuntos
Epilepsia Generalizada , Síndromes Epilépticas , Deficiência Intelectual , Canal de Sódio Disparado por Voltagem NAV1.6 , Epilepsia Generalizada/tratamento farmacológico , Epilepsia Generalizada/genética , Síndromes Epilépticas/tratamento farmacológico , Síndromes Epilépticas/genética , Estudos de Associação Genética , Humanos , Lactente , Deficiência Intelectual/genética , Mutação , Canal de Sódio Disparado por Voltagem NAV1.6/genética , Prognóstico , Convulsões/tratamento farmacológico , Convulsões/genética , Bloqueadores dos Canais de Sódio/uso terapêutico
9.
Phys Chem Chem Phys ; 25(37): 25552-25565, 2023 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-37718648

RESUMO

NiOx films grown from 50 nm thick Ni on Si(111) were put in contact with oxygen and subsequently water vapor at elevated temperatures. Near ambient pressure (NAP)-XPS and -XAS reveal the formation of oxygen vacancies at elevated temperatures, followed by H2O dissociation and saturation of the oxygen vacancies with chemisorbing OH. Through repeated heating and cooling, OH-saturated oxygen vacancies act as precursors for the formation of thermally stable NiOOH on the sample surface. This is accompanied by a significant restructuring of the surface which increases the probability of NiOOH formation. Exposure of a thin NiOx film to H2O can lead to a partial reduction of NiOx to metallic Ni accompanied by a distinct shift of the NiOx spectra with respect to the Fermi edge. DFT calculations show that the formation of oxygen vacancies and subsequently Ni0 leads to a state within the band gap of NiO which pins the Fermi edge.

10.
Neurosurg Rev ; 46(1): 226, 2023 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-37670022

RESUMO

The COVID-19 pandemic has disrupted healthcare delivery worldwide, leading to significant delays in cancer diagnosis and treatment. This study aimed to investigate the impact of the pandemic on the diagnosis and treatment of malignant brain tumors, specifically glioblastoma (GBM) and cerebral metastasis (CM), in a specialized neuro-oncology center. We analyzed data from 236 patients diagnosed with previously unknown malignant brain tumors between January 2018 and December 2021. Patients were classified into two groups: pre-COVID (January 2018 to December 2019) and COVID (January 2020 to December 2021). Tumor volumes were compared between the two groups and factors affecting tumor volumes were studied. Of 236 patients diagnosed with previously unknown malignant brain tumors, 114 were in the pre-COVID group and 122 were in the COVID group. Median tumor volumes at first diagnosis were significantly larger in the COVID group compared to the pre-COVID group (21.7 vs 15.7 cm3; p < 0.05). The survival times for the overall cohort and the GBM and CM subgroups did not differ significantly between the pre-COVID and COVID periods. Delays in diagnosis and treatment during the COVID-19 pandemic led to larger tumor volumes at diagnosis for patients with malignant brain tumors. However, these larger tumors did not result in worse survival outcomes. This counterintuitive finding highlights the crucial role of specialized neuro-oncological centers in mitigating the potential negative impact of delayed treatment and emphasizes the need for continued access to specialized care during times of crisis.


Assuntos
Neoplasias Encefálicas , COVID-19 , Glioblastoma , Humanos , Pandemias
11.
Br J Neurosurg ; 37(4): 816-824, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31583911

RESUMO

We report the case of a 28-year-old female patient who complained of extreme neck pain when giving birth to a child. Magnetic resonance imaging (MRI) of the cervical spine demonstrated an osteolytic lesion at the second cervical vertebral body (C2). In this presentation, we highlight a transoral surgical approach in order to prevent instability of this osteolytic lesion. To the best of our knowledge, this is the first time that such a route of access has been described for this tumor entity. A histopathologic examination led to the diagnosis of epithelioid hemangioendothelioma. During a follow-up period of 33 months, the patient had no complaints.


Assuntos
Hemangioendotelioma Epitelioide , Osteólise , Neoplasias da Coluna Vertebral , Gravidez , Feminino , Criança , Humanos , Adulto , Hemangioendotelioma Epitelioide/diagnóstico por imagem , Hemangioendotelioma Epitelioide/cirurgia , Osteólise/diagnóstico por imagem , Osteólise/etiologia , Osteólise/cirurgia , Corpo Vertebral/patologia , Neoplasias da Coluna Vertebral/diagnóstico por imagem , Neoplasias da Coluna Vertebral/cirurgia , Vértebras Cervicais/diagnóstico por imagem , Vértebras Cervicais/cirurgia , Vértebras Cervicais/patologia , Hormônios
12.
Sensors (Basel) ; 23(23)2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-38067918

RESUMO

Optical methods such as ultraviolet/visible (UV/Vis) and fluorescence spectroscopy are well-established analytical techniques for in situ water quality monitoring. A broad range of bio-logical and chemical contaminants in different concentration ranges can be detected using these methods. The availability of results in real time allows a quick response to water quality changes. The measuring devices are configured as portable multi-parameter probes. However, their specification and data processing typically cannot be changed by users, or only with difficulties. Therefore, we developed a submersible sensor probe, which combines UV/Vis and fluorescence spectroscopy together with a flexible data processing platform. Due to its modular design in the hardware and software, the sensing system can be modified to the specific application. The dimension of the waterproof enclosure with a diameter of 100 mm permits also its application in groundwater monitoring wells. As a light source for fluorescence spectroscopy, we constructed an LED array that can be equipped with four different LEDs. A miniaturized deuterium-tungsten light source (200-1100 nm) was used for UV/Vis spectroscopy. A miniaturized spectrometer with a spectral range between 225 and 1000 nm permits the detection of complete spectra for both methods.

13.
Semin Cancer Biol ; 71: 52-64, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-32920126

RESUMO

Vessel co-option is an alternative strategy by which tumour cells vascularize and gain access to nutrients to support tumour growth, survival and metastasis. In vessel co-option, the cancer cells move towards the pre-existing vasculature and hijack them. Vessel co-option is adopted by a wide range of human tumours including colorectal cancer liver metastases (CRCLM) and is responsible for the effectiveness of treatment in CRCLM. Furthermore, vessel co-option is an intrinsic feature and an acquired mechanism of resistance to anti-angiogenic treatment. In this review, we describe the microenvironment, the molecular players, discovered thus far of co-opting CRCLM lesions and propose a theoretical model. We also highlight key unanswered questions that are critical to improving our understanding of CRCLM vessel co-option and for the development of effective approaches for the treatment of co-opting tumours.


Assuntos
Neoplasias Colorretais/patologia , Neoplasias Hepáticas/secundário , Modelos Teóricos , Neovascularização Patológica/patologia , Microambiente Tumoral , Animais , Neoplasias Colorretais/imunologia , Humanos , Neoplasias Hepáticas/imunologia , Neovascularização Patológica/imunologia
14.
Am J Physiol Regul Integr Comp Physiol ; 323(6): R935-R950, 2022 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-36283086

RESUMO

Exertional heat stroke (EHS) is a potentially lethal condition resulting from high core body temperatures (TC) in combination with a systemic inflammatory response syndrome (SIRS) with varying degrees of severity across victims, and limited understanding of the underlying mechanism(s). We established a mouse model of severe EHS to identify mechanisms of hyperthermia/inflammation that may be responsible for organ damage. Mice were forced to run on a motorized wheel in a 37.5°C chamber until loss of consciousness and were either removed immediately (exertional heat injury or EHI; TCMax = 42.4 ± 0.2°C) or remained in the chamber an additional 20 min (EHS; TCMax = 42.5 ± 0.4°C). Exercise control mice (ExC) experienced identical procedures to EHS at 25°C. At 3 h post-EHS, there was evidence for an immune/inflammatory response as elevated blood chemokine [interferon γ-induced protein 10 (IP-10), keratinocytes-derived chemokine (KC), macrophage inflammatory proteins (MIP-1α), MIP-1ß, MIP-2] and cytokine [granulocyte colony-stimulating factor (G-CSF), interleukins (IL-10), IL-6] levels peaked and were highest in EHS mice compared with EHI and ExC mice. Immunoblotting of organs susceptible to EHS damage indicated that several kinases were sensitive to stress associated with heat/inflammation and exercise; specifically, phosphorylation of liver c-Jun NH2-terminal kinase (JNK) at threonine 183/tyrosine 185 immediately (0 h) postheating related to heat illness severity. We have established a mouse EHS model, and JNK [or its downstream target(s)] could underlie EHS symptomatology, allowing the identification of molecular pathways or countermeasure targets to mitigate heat illness severity, enable complete recovery, and decrease overall EHS-related fatalities.


Assuntos
Transtornos de Estresse por Calor , Golpe de Calor , Camundongos , Animais , Modelos Animais de Doenças , Quimiocinas , Inflamação
15.
Am J Physiol Regul Integr Comp Physiol ; 323(5): R638-R647, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-36094451

RESUMO

Military and/or emergency services personnel may be required to perform high-intensity physical activity during exposure to elevated inspired carbon dioxide (CO2). Although many of the physiological consequences of hypercapnia are well characterized, the effects of graded increases in inspired CO2 on self-paced endurance performance have not been determined. The aim of this study was to compare the effects of 0%, 2%, and 4% inspired CO2 on 2-mile run performance, as well as physiological and perceptual responses during time trial exercise. Twelve physically active volunteers (peak oxygen uptake = 49 ± 5 mL·kg-1·min-1; 3 women) performed three experimental trials in a randomized, single-blind, crossover manner, breathing 21% oxygen with either 0%, 2%, or 4% CO2. During each trial, participants completed 10 min of walking at ∼40% peak oxygen uptake followed by a self-paced 2-mile treadmill time trial. One participant was unable to complete the 4% CO2 trial due to lightheadedness during the run. Compared with the 0% CO2 trial, run performance was 5 ± 3% and 7 ± 3% slower in the 2% and 4% CO2 trials, respectively (both P < 0.001). Run performance was significantly slower with 4% versus 2% CO2 (P = 0.046). The dose-dependent performance impairments were accompanied by stepwise increases in mean ventilation, despite significant reductions in running speed. Dyspnea and headache were significantly elevated during the 4% CO2 trial compared with both the 0% and 2% trials. Overall, our findings show that graded increases in inspired CO2 impair endurance performance in a stepwise manner in healthy humans.


Assuntos
Dióxido de Carbono , Hipercapnia , Feminino , Humanos , Teste de Esforço , Oxigênio , Consumo de Oxigênio/fisiologia , Resistência Física/fisiologia , Método Simples-Cego
16.
J Therm Biol ; 108: 103271, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36031203

RESUMO

Telemetric temperature capsules are frequently utilized to measure deep body temperature. Whereas most methods to measure temperature are conducted at a single site (e.g., rectal temperature), the location of ingested telemetry capsules varies. If distinct regions of the gastrointestinal tract have different temperatures, the measurements obtained using telemetry capsules will vary accordingly. This study examined the agreement of two telemetric temperature capsules in fifty-seven Army Ranger School students ingested 64 and 16 h before a cool weather waterborne movement. Twenty-one subjects (37%) (age: 25 ± 4, weight: 81±7 kg) retained both capsules. Subjects completed activities that could increase (e.g. exercise) and decrease (e.g. cold water immersion) body temperature. Agreement between the two capsules was assessed through concordance and Bland Altman analysis using a linear mixed model. Bias between the two capsules was low (0.01 °C, SE = 0.03, before a neck-deep immersion river crossing and -0.09 °C, SE = 0.08, after the river crossing), but there were large differences in the variance components (0.044 vs 0.155 total variance for the pre-crossing vs the post-crossing data). The 95% Limits of Agreement indicate that discordance between the two capsules was lower before the river crossing (-0.40 to +0.42 °C) than after (-0.86 to +0.68 °C). In summary, this study examined telemetry capsule agreement with more time between capsule ingestion (48 h) in a larger sample size than most previous studies on the topic, and found notable (95% LoA>0.4 °C) variability between the two capsules which was exacerbated after crossing a cold river. Differences in gastrointestinal location of telemetry capsules can introduce variability into the measurement of deep body temperature due to regional temperature differences. This variability may be acceptable for some study designs, but unacceptable when small changes in temperature are important to detect. If the convenience of telemetric temperature capsules is desired, an alternative is to use the capsule as a rectal suppository.


Assuntos
Temperatura Corporal , Telemetria , Adulto , Cápsulas , Exercício Físico , Humanos , Temperatura , Adulto Jovem
17.
Hum Brain Mapp ; 42(3): 737-752, 2021 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-33103324

RESUMO

Numerous neuroimaging studies in amyotrophic lateral sclerosis (ALS) have reported links between structural changes and clinical data; however phenotypic and disease course heterogeneity have occluded robust associations. The present study used the novel D50 model, which distinguishes between disease accumulation and aggressiveness, to probe correlations with measures of diffusion tensor imaging (DTI). DTI scans of 145 ALS patients and 69 controls were analyzed using tract-based-spatial-statistics of fractional anisotropy (FA), mean- (MD), radial (RD), and axial diffusivity (AD) maps. Intergroup contrasts were calculated between patients and controls, and between ALS subgroups: based on (a) the individual disease covered (Phase I vs. II) or b) patients' disease aggressiveness (D50 value). Regression analyses were used to probe correlations with model-derived parameters. Case-control comparisons revealed widespread ALS-related white matter pathology with decreased FA and increased MD/RD. These affected pathways showed also correlations with the accumulated disease for increased MD/RD, driven by the subgroup of Phase I patients. No significant differences were noted between patients in Phase I and II for any of the contrasts. Patients with high disease aggressiveness (D50 < 30 months) displayed increased AD/MD in bifrontal and biparietal pathways, which was corroborated by significant voxel-wise regressions with D50. Application of the D50 model revealed associations between DTI measures and ALS pathology in Phase I, representing individual disease accumulation early in disease. Patients' overall disease aggressiveness correlated robustly with the extent of DTI changes. We recommend the D50 model for studies developing/validating neuroimaging or other biomarkers for ALS.


Assuntos
Esclerose Lateral Amiotrófica/patologia , Imagem de Tensor de Difusão , Progressão da Doença , Modelos Neurológicos , Substância Branca/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Esclerose Lateral Amiotrófica/diagnóstico por imagem , Esclerose Lateral Amiotrófica/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Substância Branca/diagnóstico por imagem
18.
Genet Med ; 23(8): 1492-1497, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33911214

RESUMO

PURPOSE: Genetic diagnostics of neurodevelopmental disorders with epilepsy (NDDE) are predominantly applied in children, thus limited information is available regarding adults or elderly. METHODS: We investigated 150 adult/elderly individuals with NDDE by conventional karyotyping, FMR1 testing, chromosomal microarray, panel sequencing, and for unresolved cases, also by exome sequencing (nsingle = 71, ntrios = 24). RESULTS: We identified (likely) pathogenic variants in 71 cases (47.3%) comprising fragile X syndrome (n = 1), disease-causing copy number (n = 23), and single-nucleotide variants (n = 49). Seven individuals displayed multiple independent genetic diagnoses. The diagnostic yield correlated with the severity of intellectual disability. Individuals with anecdotal evidence of exogenic early-life events (e.g., nuchal cord, complications at delivery) with alleged/unproven association to the disorder had a particularly high yield of 58.3%. Screening for disease-specific comorbidities was indicated in 45.1% and direct treatment consequences arose in 11.8% of diagnosed individuals. CONCLUSION: Panel/exome sequencing displayed the highest yield and should be considered as first-tier diagnostics in NDDE. This high yield and the numerous indications for additional screening or treatment modifications arising from genetic diagnoses indicate a current medical undersupply of genetically undiagnosed adult/elderly individuals with NDDE. Moreover, knowledge of the course of elderly individuals will ultimately help in counseling newly diagnosed individuals with NDDE.


Assuntos
Epilepsia , Deficiência Intelectual , Transtornos do Neurodesenvolvimento , Adulto , Idoso , Epilepsia/diagnóstico , Epilepsia/genética , Proteína do X Frágil da Deficiência Intelectual/genética , Humanos , Deficiência Intelectual/diagnóstico , Deficiência Intelectual/genética , Cariotipagem , Sequenciamento do Exoma
19.
Epilepsia ; 62(10): 2518-2527, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34378197

RESUMO

OBJECTIVE: Dravet syndrome (DS) is a rare but severe drug-resistant epilepsy. Before the approval of fenfluramine (FFA) for the treatment of seizures in DS, patients in Germany could receive treatment under a compassionate use program (CUP). METHODS: We conducted a multicenter, retrospective, observational study to describe the efficacy, tolerability, and retention of FFA within the CUP. Patients received add-on therapy with oral FFA gradually titrated to a target dose between .13 and .7 mg/kg/day. RESULTS: Overall, 78 patients with DS (median age = 8.0 years, range = 2.1-46.0; 53% female, median concomitant antiseizure medications [ASMs] = 3) were treated with FFA for a median duration of 255.5 days (range = 31-572). Responder rates (a ≥50% reduction; n = 78) and seizure-freedom rates at 3 months were 68% and 14% for total seizures, respectively, and 67% and 23% for generalized tonic-clonic seizures. Responder rates were consistent at 6 and 12 months (n = 66 and n = 43, respectively). Median seizure days per month significantly decreased from 10.0 (range = .5-30) to 3.0 (range = 0-30) in the 3-month period before and after FFA treatment (p < .001). Significantly fewer patients reported at least one episode of status epilepticus (28% vs. 14% patients before and after FFA initiation, p = .005). During FFA treatment, 35 (45%) patients were able to discontinue a concomitant ASM. At the last follow-up date, 66 (85%) patients remained on treatment with FFA. The most common adverse events were somnolence (36%), decreased appetite (22%), and ataxia (8%). Forty-eight (62%) patients were reported as having a meaningful global clinical improvement. SIGNIFICANCE: In a large cohort of patients, FFA demonstrated efficacy across a range of outcomes including clinically significant reductions in convulsive seizures, and was well tolerated, providing valuable information for real-world practice.


Assuntos
Ensaios de Uso Compassivo , Epilepsias Mioclônicas , Adolescente , Adulto , Anticonvulsivantes/efeitos adversos , Criança , Pré-Escolar , Epilepsias Mioclônicas/induzido quimicamente , Epilepsias Mioclônicas/complicações , Epilepsias Mioclônicas/tratamento farmacológico , Síndromes Epilépticas , Feminino , Fenfluramina/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Convulsões/complicações , Espasmos Infantis , Resultado do Tratamento , Adulto Jovem
20.
J Pathol ; 251(2): 213-223, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32297656

RESUMO

Colorectal cancer liver metastases (CRCLM) that present with a replacement histopathological growth pattern (HGP) are resistant to neoadjuvant anti-angiogenic therapy. Surrogate biomarkers are not available to preoperatively identify patients with these tumors. Here we identify differentially expressed genes between CRCLM with a replacement HGP and those with a desmoplastic HGP using RNA sequencing. We demonstrate that LOXL4 is transcriptionally upregulated in replacement HGP CRCLM compared with desmoplastic HGP CRCLM and the adjacent normal liver. Interestingly, lysyl oxidase-like 4 (LOXL4) protein was expressed by neutrophils present in the tumor microenvironment in replacement HGP CRCLM. We further demonstrate that LOXL4 expression is higher in circulating neutrophils of cancer patients compared with healthy control patients and its expression can be induced by stimulation with lipopolysaccharide and TNF-α. Our study is the first to show the expression of LOXL4 in neutrophils and reveals the potential for LOXL4-expressing neutrophils to support the replacement HGP phenotype and to serve as a surrogate biomarker for this subtype of CRCLM. © 2020 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Biomarcadores Tumorais/metabolismo , Neoplasias Colorretais/patologia , Resistencia a Medicamentos Antineoplásicos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/enzimologia , Neutrófilos/efeitos dos fármacos , Proteína-Lisina 6-Oxidase/metabolismo , Biomarcadores Tumorais/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/secundário , Neutrófilos/enzimologia , Fenótipo , Proteína-Lisina 6-Oxidase/genética , Transdução de Sinais , Transcrição Gênica , Microambiente Tumoral , Regulação para Cima
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