Pittmanbarker7719

Z Iurium Wiki

Verze z 3. 10. 2024, 15:56, kterou vytvořil Pittmanbarker7719 (diskuse | příspěvky) (Založena nová stránka s textem „For several decades now, the analysis of steroids has been a key tool in the diagnosis and monitoring of numerous endocrine pathologies. Thus, the availabl…“)
(rozdíl) ← Starší verze | zobrazit aktuální verzi (rozdíl) | Novější verze → (rozdíl)

For several decades now, the analysis of steroids has been a key tool in the diagnosis and monitoring of numerous endocrine pathologies. Thus, the available methods used to analyze steroids in biological samples have dramatically evolved over time following the rapid pace of technology and scientific knowledge. This review aims to synthetize the advances in steroids' analysis, from classical approaches considering only a few steroids or a limited number of steroid ratios, up to the new steroid profiling strategies (steroidomics) monitoring large sets of steroids in biological matrices. In this context, the use of liquid chromatography coupled to mass spectrometry has emerged as the technique of choice for the simultaneous determination of a high number of steroids, including phase II metabolites, due to its sensitivity and robustness. However, the large dynamic range to be covered, the low natural abundance of some key steroids, the selectivity of the analytical methods, the extraction protocols, and the steroid ionization remain some of the current challenges in steroid analysis. This review provides an overview of the different analytical workflows available depending on the number of steroids under study. Special emphasis is given to sample treatment, acquisition strategy, data processing, steroid identification and quantification using LC-MS approaches. This work also outlines how the availability of steroid standards, the need for complementary analytical strategies and the improvement of calibration approaches are crucial for achieving complete steroidome quantification.Bioavailable vitamin D and vitamin D metabolite ratio (VMR) have emerged as potential novel vitamin D markers. We developed a multiplex liquid chromatography-tandem mass spectrometry (LC-MS/MS) method to determine all elements necessary for the calculation of bioavailable vitamin D and VMR, including 25-hydroxyvitamin D [25-(OH)D] and 24,25-dihydroxyvitamin D3 [24,25-(OH)2D3], VDBP and its isoforms, and albumin. Following separate reactions of hexane extraction and trypsin digestion, serum samples were analyzed using LC-MS/MS to measure 25-(OH)D3, 25-(OH)D2, 24,25-(OH)2D3, VDBP and its isoforms, and albumin. Analytical performances were assessed. Korean (n = 229), Arab (n = 98), White (n = 99) and Black American (n = 99) samples were analyzed. Bioavailable vitamin D and VMR were calculated. D-Cycloserine All target molecules were clearly separated and accurately quantified by LC-MS/MS. Analytical performances, including imprecision, accuracy, ion suppression, limit of quantification, linearity, and comparison with existing methods were within acceptable levels. The allele frequencies of VDBP isoforms in various races resulted similar to previously known values. The levels of bioavailable vitamin D were highest in White Americans and lowest in Black Americans. We have successfully developed a multiplex LC-MS/MS-based assay method that can simultaneously perform the measurement of all parameters needed to calculate bioavailable vitamin D and VMR. Our devised method was robust and reliable in terms of analytical performances and could be applied to routine clinical samples in the future to more accurately assess vitamin D status.Vitamin D/Vitamin D receptor (VDR) has been shown to inhibit the NF-κB-mediated inflammatory effects. Up-regulation of the NLRP3(Recombinant NLR Family, Pyrin Domain Containing Protein 3)/Caspase-1/GSDMD (Gasdermin D) pathway through NF-κb is one of the key mechanisms leading to pyroptosis. This study aims to explore the effects of vitamin D/VDR on the pyroptosis pathway in cisplatin induced acute kidney injury (AKI) models. Our results showed that in wide type mice, renal function loss, tissue injury and cell death induced by cisplatin were alleviated by pretreatment of high-dose paricalcitol(a VDR agonist) accompanied with up-regulated VDR and decreased expression of NLRP3, GSDMD-N, Cleaved-Caspase-1 and mature Interleukin- 1β (features of pyroptosis). While, in VDR knock out mice, cisplatin induced more severer renal injury and further increased pyroptosis related protein than the wild type mice and the effect of paricalcitol were also eliminated. In tubular cell specific VDR-over expressing mice, those renal injury index as well as pyroptosis phenotype were significantly reduced by low-dose paricalcitol pretreatment with upregulated VDR expression compared with WT mice. In vitro data using gain and lose function experiments in Human tubular epithelial cell (HK-2) were consistent with the observation as in vivo work. Our further experiments in both animal and cell culture work has found that the level of IκBα(Inhibitor of NF-κB) were decreased and the nuclear level of NF-κB p65 of renal tubular cells were increased after cisplatin injury while VDR activation by paricalcitol could reverse up-regulation of nuclear NF-κB p65 with reduced cell pyroptosis. These data suggested that vitamin D/VDR could alleviate cisplatin-induced acute renal injury partly by inhibiting NF-κB-mediated NLRP3/Caspase-1/GSDMD pyroptosis.The type 1 and type 2 cannabinoid receptors are G protein-coupled receptors implicated in a variety of physiological processes and diseases. Synthetic cannabinoid receptor agonists (SCRAs) were originally developed to explore the therapeutic benefits of cannabinoid receptor activation, although more recently, these compounds have been diverted to the recreational drug market and are increasingly associated with incidences of toxicity. A prominent concept in contemporary pharmacology is functional selectivity or biased agonism, which describes the ability of ligands to elicit differential activation of signalling pathways through stabilisation of distinct receptor conformations. Biased agonists may maximise drug effectiveness by reducing on-target adverse effects if they are mediated by signalling pathways distinct from those that drive the therapeutic effects. For the cannabinoid receptors, it remains unclear as to which signalling pathways mediate desirable and adverse effects. However, given their structural diversity and potential to induce a plethora of signalling effects, SCRAs provide the most promising prospect for detecting and studying bias at the cannabinoid receptors. This review summarises the emerging evidence of SCRA bias at the cannabinoid receptors.COVID-19 can involve several organs and systems, often with indirect and poorly clarified mechanisms. Different presentations of myocardial injury have been reported, with variable degrees of severity, often impacting on the prognosis of COVID-19 patients. The pathogenic mechanisms underlying cardiac damage in SARS-CoV-2 infection are under active investigation. We report the clinical and autopsy findings of a fatal case of Takotsubo Syndrome occurring in an 83-year-old patient with COVID-19 pneumonia. The patient was admitted to Emergency Department with dyspnea, fever and diarrhea. A naso-pharyngeal swab test for SARS-CoV-2 was positive. In the following week his conditions worsened, requiring intubation and deep sedation. While in the ICU, the patient suddenly showed ST segment elevation. Left ventricular angiography showed decreased with hypercontractile ventricular bases and mid-apical ballooning, consistent with diagnosis of Takotsubo syndrome. Shortly after the patient was pulseless. After extensive resuscitation maneuvers, the patient was declared dead. Autopsy revealed a subepicardial hematoma, in absence of myocardial rupture. On histology, the myocardium showed diffuse edema, multiple foci of contraction band necrosis in both ventricles and occasional coagulative necrosis of single cardiac myocytes. Abundant macrophages CD68+ were detected in the myocardial interstitium. The finding of diffuse contraction band necrosis supports the pathogenic role of increased catecholamine levels; the presence of a significant interstitial inflammatory infiltrate, made up by macrophages, remains of uncertain significance.

Volumetric arc therapy (VMAT) is a radiation therapy (RT) technique that spares normal tissues from high and intermediate RT doses but increases the volume of tissues receiving low doses of RT compared with 3-dimensional conformal RT (3DCRT). We hypothesized that palliative VMAT would reduce the detriment to patient quality of life (QOL) compared with palliative 3DCRT.

This phase 2 trial randomized patients to palliative RT using VMAT or 3DCRT to 1 painful site of metastatic disease in the trunk. Treating physicians could choose 8 Gy in 1 fraction or 20 Gy in 5 fractions to stratify randomization. The primary endpoint was the change in European Organization for Research and Treatment of Cancer Quality of Life Questionnaire Version 3.0 (EORTC QLQ-C30) global health status QOL subscale at 1 week after RT. Repeated measures analysis of variance was used to assess the relationship of patient QOL over time with other factors.

From July 2014 to November 2017, 37 patients who underwent 3DCRT and 32 patients whid at 4 weeks after RT.

The use of stereotactic body radiation therapy (SBRT) in pediatric patients has been underreported. We reviewed practice patterns, outcomes, and toxicity of SBRT in this population.

In this multi-institutional study, 55 patients with 107 non-central nervous system lesions treated with SBRT between 2010 and 2016 were reviewed. Treatment response was evaluated by Response Evaluation Criteria in Solid Tumors (RECIST) v1.1 and modified RECIST v1.1 criteria for soft-tissue and bone lesions, respectively. Patterns of local failure (LF) were assessed dosimetrically. The cumulative incidence of LF and toxicity were estimated accounting for the competing risk event of death. Predictors of LF were identified through joint frailty models for clustered competing risks.

The median (range) dose/fraction was 7 (4.5-25) Gy, the total (range) dose/site was 35 (12-45), and the median (range) number of fractions was 5 (1-9). The radiographic response rates of bone and soft-tissue lesions were 90.6% and 76.7%, respectivelyand resulted in radiographic response and symptom palliation in most pediatric patients with advanced disease. The 1-year cumulative LF rate of 25% will serve as a benchmark for further modifications to radiation therapy indications, parameters, and combination therapy.

We conducted a phase 3 randomized clinical trial to assess whether radical hemithoracic radiation therapy (RHR) compared with palliative radiation therapy (PR) can achieve overall survival (OS) advantages in patients with malignant pleural mesothelioma (MPM).

From August 2014 to May 2018, patients with histologically diagnosed nonmetastatic MPM, who underwent nonradical lung-sparing surgery and chemotherapy (CHT), were randomly assigned (11) to receive RHR or PR. RHR total dose to the involved pleural cavity was 50 Gy in 25 fractions, and the gross residual disease received a simultaneous integrated boost of 60 Gy. The primary endpoint was OS. Secondary endpoints were local control, distant metastasis-free survival, progression-free survival, and acute and late toxicity rates. A sample size of 108 patients considering a type I error (α) of 0.05 and a statistical power of 80% was calculated to prove that RHR could improve the 2-year OS. OS was estimated with the Kaplan-Meier method and the log-rank test (2-sided) tested differences between arms.

Autoři článku: Pittmanbarker7719 (Burns Henson)