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1.
Adv Sci (Weinh) ; : e2403647, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-39146196

RESUMEN

The significant role of the cathodic binder in modulating mass transport within the catalyst layer (CL) of fuel cells is essential for optimizing cell performance. This investigation focuses on enhancing the membrane electrode assembly (MEA) through the utilization of a short-side-chain perfluoro-sulfonic acid (SSC-PFSA) ionomer as the cathode binder, referred to as SSC-MEA. This study meticulously visualizes the distinctive interpenetrating networks of ionomers and catalysts, and explicitly clarifies the triple-phase interface, unveiling the transport-friendly microstructure and transport mechanisms inherent in SSC-MEA. The SSC-MEA exhibits advantageous microstructural features, including a better-connected ionomer network and well-organized hierarchical porous structure, culminating in superior mass transfer properties. Relative to the MEA bonded by long-side-chain perfluoro-sulfonic acid (LSC-PFSA) ionomer, noted as LSC-MEA, SSC-MEA exhibits a notable peak power density (1.23 W cm-2), efficient O2 transport, and remarkable proton conductivity (65% improvement) at 65 °C and 70% relativity humidity (RH). These findings establish crucial insights into the intricate morphology-transport-performance relationship in the CL, thereby providing strategic guidance for developing highly efficient MEA.

2.
Science ; 385(6710): 796-800, 2024 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-39146411

RESUMEN

In the underdoped n-type cuprate Nd2-xCexCuO4, long-range antiferromagnetic order reconstructs the Fermi surface, resulting in a putative antiferromagnetic metal with small Fermi pockets. Using angle-resolved photoemission spectroscopy, we observe an anomalous energy gap, an order of magnitude smaller than the antiferromagnetic gap, in a wide portion of the underdoped regime and smoothly connecting to the superconducting gap at optimal doping. After considering all the known ordering tendencies in tandem with the phase diagram, we hypothesize that the normal-state gap in the underdoped n-type cuprates originates from Cooper pairing. The high temperature scale of the normal-state gap raises the prospect of engineering higher transition temperatures in the n-type cuprates comparable to those of the p-type cuprates.

3.
bioRxiv ; 2024 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-39149249

RESUMEN

We employed laser microdissection to selectively harvest tumor cells and stroma from the microenvironment of formalin-fixed, paraffin-embedded head and neck squamous cell carcinoma (HNSCC) tissues. The captured HNSCC tissue fractions were analyzed by quantitative mass spectrometry-based proteomics using a data independent analysis approach. In paired samples, we achieved excellent proteome coverage having quantified 6,668 proteins with a median quantitative coefficient of variation under 10%. We observed significant differences in relevant functional pathways between the spatially resolved tumor and stroma regions. Our results identified extracellular matrix (ECM) as a major component enriched in the stroma, including many cancer associated fibroblast signature proteins in this compartment. We demonstrate the potential for comparative deep proteome analysis from very low starting input in a scalable format that is useful to decipher the alterations in tumor and the stromal microenvironment. Correlating such results with clinical features or disease progression will likely enable identification of novel targets for disease classification and interventions.

4.
Epidemiology ; 35(5): 660-666, 2024 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-39109817

RESUMEN

PURPOSE: Breast cancer has an average 10-year relative survival reaching 84%. This favorable survival is due, in part, to the introduction of biomarker-guided therapies. We estimated the population-level effect of the introduction of two adjuvant therapies-tamoxifen and trastuzumab-on recurrence using the trend-in-trend pharmacoepidemiologic study design. METHODS: We ascertained data on women diagnosed with nonmetastatic breast cancer who were registered in the Danish Breast Cancer Group clinical database. We used the trend-in-trend design to estimate the population-level effect of the introduction of (1) tamoxifen for postmenopausal women with estrogen receptor (ER)-positive breast cancer in 1982, (2) tamoxifen for premenopausal women diagnosed with ER-positive breast cancer in 1999, and (3) trastuzumab for women <60 years diagnosed with human epidermal growth factor receptor 2-positive breast cancer in 2007. RESULTS: For the population-level effect of the introduction of tamoxifen among premenopausal women diagnosed with ER-positive breast cancer in 1999, the risk of recurrence decreased by nearly one-half (OR = 0.52), consistent with evidence from clinical trials; however, the estimate was imprecise (95% confidence interval [CI] = 0.25, 1.85). We observed an imprecise association between tamoxifen use and recurrence from the time it was introduced in 1982 (OR = 1.24 95% CI = 0.46, 5.11), inconsistent with prior knowledge from clinical trials. For the introduction of trastuzumab in 2007, the estimate was also consistent with trial evidence, though imprecise (OR = 0.51; 95% CI = 0.21, 22.4). CONCLUSIONS: We demonstrated how novel pharmacoepidemiologic analytic designs can be used to evaluate the routine clinical care and effectiveness of therapeutic advancements in a population-based setting while considering some limitations of the approach.


Asunto(s)
Neoplasias de la Mama , Recurrencia Local de Neoplasia , Tamoxifeno , Trastuzumab , Humanos , Neoplasias de la Mama/tratamiento farmacológico , Femenino , Tamoxifeno/uso terapéutico , Persona de Mediana Edad , Recurrencia Local de Neoplasia/epidemiología , Trastuzumab/uso terapéutico , Quimioterapia Adyuvante , Adulto , Receptores de Estrógenos , Dinamarca/epidemiología , Farmacoepidemiología , Anciano , Antineoplásicos Hormonales/uso terapéutico , Premenopausia , Receptor ErbB-2 , Posmenopausia
5.
Cureus ; 16(7): e64841, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39156275

RESUMEN

The presence of villous adenoma in the urinary tract is an exceedingly rare finding. On a histological and cytological level, this tissue is essentially identical to that typically found in the colon. These lesions do have malignancy potential and, when present with coexistent adenocarcinoma, have a risk of recurrence and metastasis even after surgical resection. Although villous adenomas of the urinary tract have been almost exclusively treated with surgical intervention in the literature, we present a case of villous adenoma with underlying adenocarcinoma of the prostatic urethra that was successfully treated with combined chemoradiation therapy. While surgical excision has been shown to be curative in diseases with isolated villous adenoma, more aggressive treatment with radiation and/or chemotherapy can be considered in patients with concurrent adenocarcinoma. However, more research into this subject is required to properly determine the best choice of therapy for this niche patient population.

6.
Open Access J Sports Med ; 15: 101-110, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39157718

RESUMEN

Background: Increases in high-intensity locomotor activity of match play have been recorded in elite soccer. This places an onus on academy practitioners to develop players for the future demands of the game. At an academy level, locomotor data are not available for analysis over a longitudinal period, and thus changes can only be assessed with physical attribute assessment. The aim of the present study is to establish if changes in physical capacity were observed in a professional Scottish soccer academy over a ten-year period. Methods: A retrospective analysis was completed where linear mixed effect (LME) models were individually fitted to explain variation across each measure of physical capacity. Model selection was undertaken with likelihood ratio tests where the initial complex models were compared to simpler nested models to arrive at the final model by maximum likelihood. Results: The main findings were that most recent players' sprint test data revealed a significant improvement in 5m, 10m and 20m sprint performance, greater increases in CMJ performance in older age groups, and greater increases in YYIR1 performance at U13 and U14. Most physical results showed increased performance with greater relative height and weight. Conclusion: Players recruited more recently to academies are fitter than they were previously. Reference values within clubs that establish first team requirements will contribute to appropriate planning and implementation of training.

7.
Clin Pharmacokinet ; 63(8): 1205-1220, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39147988

RESUMEN

BACKGROUND: The CRUCIAL trial (NCT04217421) is investigating the effect of postnatal and perioperative administration of allopurinol on postoperative brain injury in neonates with critical congenital heart disease (CCHD) undergoing cardiac surgery with cardiopulmonary bypass (CPB) shortly after birth. OBJECTIVE: This study aimed to characterize the pharmacokinetics (PK) of allopurinol and oxypurinol during the preoperative, intraoperative, and postoperative phases in this population, and to evaluate target attainment of the current dosing strategy. METHODS: Nonlinear mixed-effects modeling was used to develop population PK models in 14 neonates from the CRUCIAL trial who received up to five intravenous allopurinol administrations throughout the postnatal and perioperative periods. Target attainment was defined as achieving an allopurinol concentration >2 mg/L in at least two-thirds of the patients during the first 24 h after birth and between the start and 36 h after cardiac surgery with CPB. RESULTS: A two-compartment model for allopurinol was connected to a one-compartment model for oxypurinol with an auto-inhibition effect on the conversion, which best described the PK. In a typical neonate weighing 3.5 kg who underwent cardiac surgery at a postnatal age (PNA) of 5.6 days, the clearance (CL) of allopurinol and oxypurinol at birth was 0.95 L/h (95% confidence interval 0.75-1.2) and 0.21 L/h (0.17-0.27), respectively, which subsequently increased with PNA to 2.97 L/h and 0.41 L/h, respectively, before CPB. During CPB, allopurinol and oxypurinol CL decreased to 1.38 L/h (0.9-1.87) and 0.12 L/h (0.05-0.22), respectively. Post-CPB, allopurinol CL increased to 2.21 L/h (1.74-2.83), while oxypurinol CL dropped to 0.05 L/h (0.01-0.1). Target attainment was 100%, 53.8%, and 100% at 24 h postnatally, 24 h after the start of CPB, and 36 h after the end of cardiac surgery, respectively. The combined concentrations of allopurinol and oxypurinol maintained ≥ 90% inhibition of xanthine oxidase (IC90XO) throughout the postnatal and perioperative period. CONCLUSIONS: The minimal target concentration of allopurinol was not achieved at every predefined time interval in the CRUCIAL trial; however, the dosing strategy used was deemed adequate, since it yielded concentrations well exceeding the IC90XO. The decreased CL of both compounds during CPB suggests influence of the hypothermia, hemofiltration, and the potential sequestration of allopurinol in the circuit. The reduced CL of oxypurinol after CPB is likely attributable to impaired kidney function.


Asunto(s)
Alopurinol , Puente Cardiopulmonar , Cardiopatías Congénitas , Modelos Biológicos , Oxipurinol , Humanos , Alopurinol/farmacocinética , Alopurinol/administración & dosificación , Puente Cardiopulmonar/métodos , Recién Nacido , Cardiopatías Congénitas/cirugía , Oxipurinol/farmacocinética , Masculino , Femenino , Procedimientos Quirúrgicos Cardíacos/métodos
8.
J Infect Dis ; 2024 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-39166299

RESUMEN

Treatment regimens for post-kala-azar dermal leishmaniasis (PKDL) are usually extrapolated from those for visceral leishmaniasis (VL), but drug pharmacokinetics (PK) can differ due to disease-specific variations in absorption, distribution, and elimination. This study characterized PK differences in paromomycin and miltefosine between 109 PKDL and 264 VL patients from eastern Africa. VL patients showed 0.55-fold (95%CI: 0.41-0.74) lower capacity for paromomycin saturable reabsorption in renal tubules, and required a 1.44-fold (1.23-1.71) adjustment when relating renal clearance to creatinine-based eGFR. Miltefosine bioavailability in VL patients was lowered by 69% (62-76) at treatment start. Comparing PKDL to VL patients on the same regimen, paromomycin plasma exposures were 0.74-0.87-fold, while miltefosine exposure until the end of treatment day was 1.4-fold. These pronounced PK differences between PKDL and VL patients in eastern Africa highlight the challenges of directly extrapolating dosing regimens from one leishmaniasis presentation to another.

9.
Malar J ; 23(1): 240, 2024 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-39129018

RESUMEN

BACKGROUND: Community acceptance is an important criterion to assess in community trials, particularly for new tools that require high coverage and use by a target population. Installed on exterior walls of household structures, the attractive targeted sugar bait (ATSB) is a new vector control tool designed to attract and kill mosquitoes. ATSBs were evaluated in Western Zambia during a two-year cluster randomized controlled trial to assess the efficacy of ATSBs in reducing malaria transmission. Community acceptance of ATSBs was critical for successful trial implementation. METHODS: A community engagement strategy outlined activities and key messages to promote acceptance. Annual cross-sectional surveys, conducted during the peak transmission period, assessed households for presence of ATSBs as well as perceived benefits, concerns, and willingness to use ATSBs. Sixteen focus group discussions and 16 in-depth interviews, conducted at the end of each ATSB station deployment period, obtained a range of perceptions and household experiences with ATSB stations, as well as ITN use in the context of ATSB deployment. RESULTS: Methods used during the study to promote acceptance and continued use of ATSBs were effective in achieving greater than 90% coverage, a high (greater than 70%) level of perceived benefits, and fewer than 10% of households reporting safety concerns. Common facilitators of acceptance included the desire for protection against malaria and reduction of mosquitoes, trust in health initiatives, and understanding of the product. Common barriers to acceptance included misconceptions of product impact on mosquitoes, continued cases of malaria, association with satanism, and damage to household structures. DISCUSSION: Future use of the ATSB intervention will likely require activities that foster community acceptance before, during, and after the intervention is introduced. Additional research may be needed to understand the impact of different levels of community engagement on ATSB station coverage, ATSB station perception, and ITN use. CONCLUSION: There was high acceptance of ATSB stations during the trial in Western Zambia. Continuous and intense community engagement efforts contributed to sustained ATSB coverage and trust in the product. Acceptance of ATSBs during programmatic delivery requires further research.


Asunto(s)
Malaria , Control de Mosquitos , Zambia , Control de Mosquitos/métodos , Humanos , Malaria/prevención & control , Estudios Transversales , Femenino , Masculino , Adulto , Animales , Persona de Mediana Edad , Azúcares/administración & dosificación , Adulto Joven , Insecticidas , Adolescente
10.
JOR Spine ; 7(3): e1364, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39144499

RESUMEN

Background: In parallel with population aging, the prevalence of neurological and neurodegenerative diseases has been dramatically increasing over the past few decades. Neurodegenerative diseases reduce the quality of life of patients and impose a high cost on the health system. These slowly progressive diseases can cause functional, perceptual, and behavioral deficits in patients. Therefore, neurodegenerative impairments have always been an interesting subject for scientists and clinicians. One of these diseases is spinal cord injury (SCI). SCI can lead to irreversible damage and is classified into two main subtypes: traumatic and non-traumatic, each with very different pathophysiological features. Aims: This review aims to gather relevant information about the beneficial effects of curcumin (Cur), with specific emphasis on its anti-inflammatory properties towards spinal cord injury (SCI) patients. Materials & Methods: The review collates data from extensive in-vitro, in-vivo, and clinical trials documenting the effects of CUR on SCI. It examines the modulation of pathophysiological pathways and regulation of the inflammatory cascades after CUR administration. Results: Various pathophysiological processes involving the nuclear factor erythroid 2-related factor 2 (Nrf2), nuclear factor kappa B (NF-kB), and transforming growth factor beta (TGF-ß) signaling pathways have been suggested to exacerbate damages resulting from SCI. CUR administration showed to modulate these signaling pathways which lead to attenuation of SCI complications. Discussion: Anti-inflammatory compounds, particularly CUR, can modulate these pathophysiological pathways and regulate the inflammatory cascades. CUR, a well-known natural product with significant anti-inflammatory effects, has been extensively documented in experimental and clinical trials. Conclusion: Curcumin's potential to alter key steps in the Nrf2, NF-kB, and TGF-ß signaling pathways suggests that it may play a role in attenuating SCI complications.

11.
J Exp Med ; 221(9)2024 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-39150482

RESUMEN

Coordination of cellular metabolism is essential for optimal T cell responses. Here, we identify cytosolic acetyl-CoA production as an essential metabolic node for CD8 T cell function in vivo. We show that CD8 T cell responses to infection depend on acetyl-CoA derived from citrate via the enzyme ATP citrate lyase (ACLY). However, ablation of ACLY triggers an alternative, acetate-dependent pathway for acetyl-CoA production mediated by acyl-CoA synthetase short-chain family member 2 (ACSS2). Mechanistically, acetate fuels both the TCA cycle and cytosolic acetyl-CoA production, impacting T cell effector responses, acetate-dependent histone acetylation, and chromatin accessibility at effector gene loci. When ACLY is functional, ACSS2 is not required, suggesting acetate is not an obligate metabolic substrate for CD8 T cell function. However, loss of ACLY renders CD8 T cells dependent on acetate (via ACSS2) to maintain acetyl-CoA production and effector function. Together, ACLY and ACSS2 coordinate cytosolic acetyl-CoA production in CD8 T cells to maintain chromatin accessibility and T cell effector function.


Asunto(s)
ATP Citrato (pro-S)-Liasa , Acetatos , Acetilcoenzima A , Linfocitos T CD8-positivos , Cromatina , Ratones Endogámicos C57BL , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/metabolismo , Animales , Cromatina/metabolismo , Acetilcoenzima A/metabolismo , ATP Citrato (pro-S)-Liasa/metabolismo , ATP Citrato (pro-S)-Liasa/genética , Ratones , Acetatos/metabolismo , Acetato CoA Ligasa/metabolismo , Acetato CoA Ligasa/genética , Acetilación , Ratones Noqueados , Citosol/metabolismo , Histonas/metabolismo
12.
Appetite ; 201: 107623, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-39106642

RESUMEN

Research emphasizes the importance of considering how sociocultural factors affect the disordered eating behaviors of Asian American adults. The present study thus investigated how internalized racism and racial collective self-esteem are associated with disordered eating among Asian American adults, as well as the potential mediating role of psychological distress. A final sample of 796 Asian American adults completed a cross-sectional survey that contained the study's questionnaires. Regression analyses revealed that internalized racism was positively associated with disordered eating, whereas racial collective self-esteem was negatively associated with disordered eating among Asian American adults. Psychological distress mediated both of the aforementioned associations. Researchers and practitioners are encouraged to be cognizant about how Asian American adult clients' experiences of internalized racism and psychological distress may affect their disordered eating. Researchers and practitioners may also strive to increase racial collective self-esteem among this population. Future researchers may consider building upon these findings by conducting longitudinal research or focusing on specific Asian ethnic groups for further studies about disordered eating among Asian Americans.


Asunto(s)
Asiático , Trastornos de Alimentación y de la Ingestión de Alimentos , Racismo , Autoimagen , Humanos , Asiático/psicología , Femenino , Masculino , Adulto , Estudios Transversales , Trastornos de Alimentación y de la Ingestión de Alimentos/psicología , Trastornos de Alimentación y de la Ingestión de Alimentos/etnología , Racismo/psicología , Adulto Joven , Encuestas y Cuestionarios , Distrés Psicológico , Persona de Mediana Edad , Adolescente
13.
medRxiv ; 2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-39148828

RESUMEN

Heart failure (HF) is one of the most common, complex, heterogeneous diseases in the world, with over 1-3% of the global population living with the condition. Progression of HF can be tracked via MRI measures of structural and functional changes to the heart, namely left ventricle (LV), including ejection fraction, mass, end-diastolic volume, and LV end-systolic volume. Moreover, while genome-wide association studies (GWAS) have been a useful tool to identify candidate variants involved in HF risk, they lack crucial tissue-specific and mechanistic information which can be gained from incorporating additional data modalities. This study addresses this gap by incorporating transcriptome-wide and proteome-wide association studies (TWAS and PWAS) to gain insights into genetically-regulated changes in gene expression and protein abundance in precursors to HF measured using MRI-derived cardiac measures as well as full-stage all-cause HF. We identified several gene and protein overlaps between LV ejection fraction and end-systolic volume measures. Many of the overlaps identified in MRI-derived measurements through TWAS and PWAS appear to be shared with all-cause HF. We implicate many putative pathways relevant in HF associated with these genes and proteins via gene-set enrichment and protein-protein interaction network approaches. The results of this study (1) highlight the benefit of using multi-omics to better understand genetics and (2) provide novel insights as to how changes in heart structure and function may relate to HF.

14.
Int J Environ Health Res ; : 1-40, 2024 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-39161080

RESUMEN

Microplastics and nanoplastics (MNPs) are present in urban dust and the aquatic environments of industrialized cities. MNPs in the human body accumulate in the lymphoid follicles, Peyer's patches of the gastrointestinal tract, and pulmonary vascular endothelial cells, which slowly result in toxicity. Since previous studies introduced curcumin as a natural protective agent against environmental toxins, we reviewed preclinical studies that had used curcumin to protect organs or cells from toxicity secondary to exposure to MNPs. It was found that exposure to MNPs resulted in osteolysis, immunotoxicity, thyroid disturbances, nephrotoxicity, neurotoxicity, hepatotoxicity, pulmonary toxicity, gastrointestinal toxicity, cardiovascular toxicity, and especially endocrine, and reproductive toxicity. Nevertheless, except for one study reviewed, curcumin restored all oxidative and histopathological damages induced by MNPs to normal due to curcumin's inherent antioxidant, antiapoptotic, anti-inflammatory, and anti-proliferative properties.

15.
Artículo en Inglés | MEDLINE | ID: mdl-39162429

RESUMEN

BACKGROUND AND OBJECTIVES: Flow diversion (FD) of intracranial aneurysms (IAs) is an increasingly used and efficacious treatment modality. Transcirculation approaches, or approaches that cross the contralateral or anteroposterior arterial supply before reaching a target vessel, have been used to treat cerebrovascular pathologies when traditional approaches are unsuitable or require intraoperative complication management. This study sought to review IAs treated with FD using a transcirculation approach to determine the technique's safety and efficacy. METHODS: A systematic review of the PubMed, Scopus, Web of Science, and Embase databases was completed per Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Studies were included if they described transcirculation approaches in adult patients with IAs undergoing FD. Outcomes of interest included intraoperative complications and aneurysm occlusion rates. RESULTS: Twelve studies with 19 patients (N = 19, mean age = 54.1 y, 89.5% female) were identified. Wide-necked (N = 5, 26.3%) and saccular (N = 5, 26.3%) aneurysms were most represented, while 57.9% (N = 11) of aneurysms were unruptured and 15.8% (N = 3) of aneurysms were ruptured. The mean aneurysm sac and neck size were 16.9 mm and 11.9 mm, respectively. The most commonly deployed flow diverter was the Pipeline Embolization Device (N = 14, 73.9%). Successful FD (complete occlusion and/or good wall apposition) was recorded in 84.6% of qualifying patients with follow-up data, while 2 patients (15.4%) developed an intraoperative carotid-cavernous fistula. CONCLUSION: Transcirculation approaches to FD offer neurointerventionalists a safe and efficacious method for device deployment, rescue scenarios, and challenging anatomy. Prospective studies may determine the most appropriate indications for transcirculation approaches to FD, while novel, lower profile devices may improve its technical feasibility and safety.

16.
Anal Chem ; 96(33): 13352-13357, 2024 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-39103237

RESUMEN

Thermal desorption (TD) of wipe-based samples was coupled with an in-line dielectric barrier discharge ionization (DBDI) source and rugged compact time-of-flight mass spectrometer (MS) for the detection of explosives, propellants, and postblast debris. The chromatography-free TD-DBDI-MS platform enabled rapid and sensitive detection of organic nitramine, nitrate ester, and nitroaromatic explosives as well as black powder and black powder substitute propellants. Parametric investigations characterized the response to TD temperature and optimized DBDI voltage, aerodynamically assisted entrainment, and fragmentation through in-source collision induced dissociation (isCID). Excess nitrate generated by the DBDI source yielded predominantly nitrate-adduct formation. Subnanogram sensitivities were demonstrated for all explosives investigated, except for nitroglycerin, specifically due to its volatility. Further, most analytes/explosives exhibited tens of picograms sensitivities. The platform also demonstrated the detection of propellant and military explosives from postblast debris. The TD-DBDI-MS system performed well without the need for aerodynamically assisted entrainment (and the associated rough pump), which along with requiring no additional gases (i.e., N2 or He) or solvents, aid in potential field deployment. The ease of TD-DBDI attachment and removal added trace solid or liquid residue detection to the rugged mass spectrometer, designed primarily for the analysis of volatile organic and inorganic compounds.

18.
J Clin Invest ; 2024 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-39106106

RESUMEN

The study of transcription factors that determine specialised neuronal functions has provided invaluable insights into the physiology of the nervous system. Peripheral chemoreceptors are neurone-like electro-physiologically excitable cells that link the oxygen content of arterial blood to the neuronal control of breathing. In the adult, this oxygen chemosensitivity is exemplified by the Type I cells of the carotid body and recent work has revealed one isoform of the transcription factor HIF, HIF-2α, to have a non-redundant role in the development and function of that organ. Here we show that the activation of HIF-2α, including isolated overexpression alone, is sufficient to induce oxygen chemosensitivity in the otherwise unresponsive adult adrenal medulla. This phenotypic change in the adrenal medulla was associated with retention of extra-adrenal paraganglioma-like tissues that resemble the foetal organ of Zuckerkandl and also manifest oxygen chemosensitivity. Acquisition of chemosensitivity was associated with changes in the adrenal medullary expression of classes of genes that are ordinarily characteristic of the carotid body, including G-protein regulators and atypical subunits of mitochondrial cytochrome oxidase. Overall, the findings suggest that, at least in certain tissues, HIF-2α acts as a phenotypic driver for cells that display oxygen chemosensitivity, thus linking two major oxygen sensing systems.

19.
Obes Surg ; 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39134834

RESUMEN

PURPOSE: Previous research on obesity surgery (OS) showed that patients do not only experience weight loss but also improvements in certain mental health outcomes (e.g., depression) after OS. However, self-harm behaviors might increase after OS. Regarding self-harm, the literature is mostly limited to studies using data from hospital or emergency room charts. This longitudinal study examined self-reported self-harm behaviors and potential psychopathological correlates before and after OS. MATERIALS AND METHODS: Pre-surgery patients (N = 220) filled out a set of questionnaires before and approximately six months after OS. Self-harm behaviors were captured with the Self-Harm Inventory. The assessments further included standardized instruments to measure symptoms of depression, anxiety, eating disorders, alcohol use, and suicidal ideations. RESULTS: Any self-harm was reported by 24.6% before and by 25.0% after OS. No differences in the number of self-harm behaviors or prevalence of any self-harm before and after OS were found. Overall, 11.4% experienced self-harm behaviors at both times. A subset showed self-harm behaviors only before (13.2%) OS and another subset only after OS (13.6%). These two groups were about the same size. Self-harm behaviors showed strong associations with psychopathology after OS, especially with depression and suicidal ideation. CONCLUSION: No increase in self-harm behaviors after OS emerged. Still, a subgroup showed self-harm behaviors after OS closely linked to further psychopathology. This mirrors the need to implement screening for self-harm before and after OS into OS care. Further studies with longer follow up periods are needed to extend these findings.

20.
Anat Rec (Hoboken) ; 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39136383

RESUMEN

Recently, Yohe and Krell (The Anatomical Record, vol. 306:2765-2780) lamented the incongruence between genetics and morphology in the vomeronasal system of bats. Here, we studied 105 bat species from 19 families using histology, iodine-enhanced computed tomography (CT), and/or micro-CT. We focused on structural elements that support a functional peripheral vomeronasal receptor organ (vomeronasal organ [VNO]), together comprising the "vomeronasal complex." Our results support prior studies that describe a functional VNO in most phyllostomid bats, miniopterids, and some mormoopids (most known Pteronotus spp.). All of these species (or congeners, at least) have vomeronasal nerves connecting the VNO with the brain and some intact genes related to a functional VNO. However, some bats have VNOs that lack a neuroepithelium and yet still possess elements that aid VNO function, such as a "capsular" morphology of the vomeronasal cartilages (VNCs), and even large venous sinuses, which together facilitate a vasomotor pump mechanism that can draw fluid into the VNO. We also show that ostensibly functionless VNOs of some bats are developmentally associated with ganglionic masses, perhaps involved in endocrine pathways. Finally, we demonstrate that the capsular VNC articulates with the premaxilla or maxilla, and that these bones bear visible grooves denoting the location of the VNC. Since these paraseptal grooves are absent in bats that have simpler (bar-shaped or curved) VNCs, this trait could be useful in fossil studies. Variable retention of some but not all "functional" elements of the vomeronasal complex suggests diverse mechanisms of VNO loss among some bat lineages.

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