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1.
Spectrochim Acta A Mol Biomol Spectrosc ; 324: 124996, 2025 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-39197212

RESUMO

Based on the growing range of applications for polycations in research and commercial materials, a continuing need exists to advance the fundamental knowledge and understanding of this class of materials. Spectroscopic and solution properties characterizations of noncovalently labeled, fluorescent Alexa Fluor® dye complexes of two commercial polycations, poly(2-(trimethylamino) ethyl methacrylate) monocation and poly[bis[2-chloroethyl] ether-alt-1,3-bis[3-(dimethylamino) propyl] urea] dication are reported to help address this need. A variety of fluorescence spectroscopic methods are used with a special emphasis on fluorescence correlation spectroscopy (FCS) which is applied to characterize the Stokes radius (RS) and equilibrium dissociation constants (Kd) of dye-polycation complexes at nanomolar dye concentrations. Resulting RS values indicate dye binding to individual polycation chains. Measured Kd values in the sub-micromolar range are consistent with strong dye binding. Increasing solution ionic strength with sodium chloride addition inhibits dye binding and decreases the RS of dye-polycation complexes due to size collapse of polycation chains. The complexes differ in their solution stability to ionic strength changes suggesting that both electrostatic and hydrophobic binding interactions influence dye binding. This study establishes the viability of noncovalent dye-polycation complexation in concert with FCS characterization as a general approach for investigating the properties of quaternary ammonium ion containing polycations in aqueous solution.

2.
Methods Mol Biol ; 2848: 187-196, 2025.
Artigo em Inglês | MEDLINE | ID: mdl-39240524

RESUMO

In several ocular diseases, degeneration of retinal neurons can lead to permanent blindness. Transplantation of stem cell (SC)-derived RGCs has been proposed as a potential therapy for RGC loss. Although there are reports of successful cases of SC-derived RGC transplantation, achieving long-distance regeneration and functional connectivity remains a challenge. To address these hurdles, retinal organoids are being used to study the regulatory mechanism of stem cell transplantation. Here we present a modified protocol for differentiating human embryonic stem cells (ESCs) into retinal organoids and transplanting organoid-derived RGCs into the murine eyes.


Assuntos
Diferenciação Celular , Células-Tronco Embrionárias Humanas , Células Ganglionares da Retina , Humanos , Animais , Camundongos , Células-Tronco Embrionárias Humanas/citologia , Células Ganglionares da Retina/citologia , Transplante de Células-Tronco/métodos , Organoides/citologia , Organoides/transplante , Técnicas de Cultura de Células/métodos , Terapia Baseada em Transplante de Células e Tecidos/métodos , Retina/citologia , Células-Tronco Embrionárias/citologia
3.
Adv Exp Med Biol ; 1456: 49-66, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39261423

RESUMO

Major depressive disorder (MDD) is a highly prevalent psychiatric disorder, associated with substantial burden and large economical costs. Notwithstanding various conventional antidepressant treatment options, a large portion of depressed people (ca. 30%) fails to respond to first-line treatment, resulting in treatment-resistant depression (TRD). Although non-response to multiple antidepressant interventions is a common outcome, a consensus definition of TRD is not yet available. In practice, TRD is applied when two or more successive treatments with different antidepressants are not working. The last decade's intense research into new medicines for TRD has led to two developments, using typical or serotonergic (psilocybin, ayahuasca) and atypical (glutamatergic) psychedelics (ketamine, esketamine). Both approaches, although via different entrance mechanism, exhibit a fast onset but also long-lasting antidepressant effect far beyond the biological presence of the drug in the body, strongly indicating that downstream mechanisms activated by signaling cascades in the brain are involved. The present chapter describes the clinical development of psilocybin and esketamine for TRD and discusses the problems involved in the use of a proper placebo because of the psychotomimetic (psilocybin) or dissociative (ketamine) effects that interfere with performing "blind" studies. Nevertheless, intranasal esketamine was developed and approved for TRD, whereas psilocybin has shown positive results. Adverse effects and tolerability of both drugs in the dose ranges used are generally acceptable. The emergence of anti-TRD medicines for treatment of a very severe disease is a breakthrough in psychiatry.


Assuntos
Antidepressivos , Transtorno Depressivo Resistente a Tratamento , Alucinógenos , Ketamina , Psilocibina , Humanos , Transtorno Depressivo Resistente a Tratamento/tratamento farmacológico , Alucinógenos/uso terapêutico , Alucinógenos/efeitos adversos , Alucinógenos/farmacologia , Ketamina/uso terapêutico , Ketamina/efeitos adversos , Psilocibina/uso terapêutico , Psilocibina/efeitos adversos , Psilocibina/farmacologia , Antidepressivos/uso terapêutico , Antidepressivos/efeitos adversos , Antidepressivos/farmacologia , Transtorno Depressivo Maior/tratamento farmacológico , Resultado do Tratamento
4.
Bioorg Med Chem Lett ; 112: 129943, 2024 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-39222892

RESUMO

Increased expression and activity of the PD-L1/PD-1 pathway suppresses the activation of cytotoxic T cells, which is vital in anti-tumour defence, allowing tumours to rise, expand and progress. Current strategies using antibodies to target PD-1/PD-L1 have been very effective in cancer therapeutics and companion diagnostics. Aptamers are a new class of molecules that offer an alternative to antibodies. Herein, the systematic evolution of ligands by exponential enrichment (SELEX) using agarose slurry beads was conducted to isolate DNA aptamers specific to recombinant human PD-L1 (rhPD-L1). Isolated aptamers were sequenced and analysed using MEGA X and structural features were examined using mFold. Three aptamer candidates (P33, P32, and P12) were selected for evaluation of binding affinity (dissociation constant, Kd) using ELONA and specificity and competitive inhibition assessment using the potentiostat-electrochemical method. Among those three, P32 displayed the highest specificity (8 nM) against PD-L1. However, P32 competes for the same binding site with the control antibody, 28-8. This study warrants further assessment of P32 aptamer as a potential, cost-effective alternative tool for targeting PD-L1.

5.
Food Res Int ; 194: 114881, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39232554

RESUMO

A novel gradient-temperature heating regime was proposed to improve the texture of braised pork. Compared with one-stage pressure heat treatment of around 107 °C, the gradient-temperature heat regime of preheating at 60 °C, followed by a slow increase of temperature to 107 °C and simmering at 97 °C increased the retention of immobilized water and reduced the shear force of meat. In this cooking regime, preheating treatment at 50-60 °C could promote the dissociation of thin and thick myofilaments, which contributed to a weakened shrinkage of myofibrils during the subsequent high temperature heating process. Pressure-heating treatment with a slow increasing temperature and the medium-temperature simmering significantly reduced (p < 0.05) the oxidation of sulfhydryl groups and the loss of α-helical, which weakened the excessive aggregation of protein and promoted the formation of myofibril network. Both the weakened shrinkage and the formation of myofibril network during gradient-temperature heating contributed to the decreased shear force and an increased immobilized water. Hence, the reduction of the oxidation and aggregation of the proteins is the key to improve the tenderness of the braised meat.


Assuntos
Culinária , Temperatura Alta , Animais , Culinária/métodos , Suínos , Miofibrilas/química , Oxirredução , Água/química , Carne de Porco/análise , Resistência ao Cisalhamento , Manipulação de Alimentos/métodos
6.
Angew Chem Int Ed Engl ; : e202415540, 2024 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-39233328

RESUMO

Using combinatory electrolyte blends represents an imperative avenue to achieve good magnesium (Mg)-metal anode compatibility and commercial feasibility in fields of promising rechargeable Mg batteries. However, fundamental challenges of how to manipulate component modifier reactivity on molecule level still remain to be solved. Here, molecular structure design concepts towards seeking bromophenyl complex-based component modifiers has been proposed according to implications of electron-donating and/or electron-withdrawing substituents on Br-C bond dissociation reactivity. Exceptional Mg electro-plating/stripping properties (a stable cycle life of 250 days in Mg//Cu asymmetric cells) have been firstly achieved in a simple salt electrolyte with 1-(3-bromophenyl)-N,N-dimethylmethanamine (BPDMA) as optimal component modifier. Comprehensive analyses disclose the unique electrochemically-active Br-containing ion-pairs formation, such as [(Mg2+)2(TFSI-)Br-]2+ and [(Mg2+)2(TFSI-)(Br-)(G2)2]2+, which results in the much thinner Br- containing and organic-inorganic mixed interphases on Mg-metal anodes. Furthermore, conventional MgSO4-based electrolytes and even calcium (Ca)-ion electrolytes can also be revived by similar strategy, demonstrating its generality and superiority.

7.
Proteomics ; : e2400223, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39233542

RESUMO

Adeno-associated viruses (AAVs) are common vectors for emerging gene therapies due to their lack of pathogenicity in humans. Here, we present our investigation of the viral proteins (i.e., VP1, VP2, and VP3) of the capsid of AAVs via top-down mass spectrometry (MS). These proteins, ranging from 59 to 81 kDa, were chromatographically separated using hydrophilic interaction liquid chromatography and characterized in the gas-phase by high-resolution Orbitrap Fourier transform MS. Complementary ion dissociation methods were utilized to improve the overall sequence coverage. By reducing the overlap of product ion signals via proton transfer charge reduction on the Orbitrap Ascend BioPharma Tribrid mass spectrometer, the sequence coverage of each VP was significantly increased, reaching up to ∼40% in the case of VP3. These results showcase the improvements in the sequencing of proteins >30 kDa that can be achieved by manipulating product ions via gas-phase reactions to obtain easy-to-interpret fragmentation mass spectra.

8.
Asian J Psychiatr ; 101: 104195, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39236529

RESUMO

There is an ongoing debate regarding whether ICD-11 complex PTSD and DSM-5 borderline personality disorder (BPD) are the same syndrome. Little is known about the extent to which these two conditions overlap and whether they exhibit distinct clinical correlates in Asian cultures. This study examined the co-occurrence of ICD-11 complex PTSD and DSM-5 BPD in a sample of treatment seekers in Hong Kong (N = 220). Participants completed validated self-report measures which assessed if they met the respective diagnostic criteria. In this sample, 30.9 % met the ICD-11 criteria for complex PTSD only, 10.0 % met the DSM-5 criteria for BPD only, and 28.2 % met the criteria for both conditions. Complex PTSD symptoms were most strongly associated with depressive symptoms (ß =.347, p <.001) and trauma-related maladaptive beliefs (ß =.337, p <.001), while BPD symptoms were most strongly associated with dissociative symptoms (ß =.281, p <.001). This study is the first to show that ICD-11 complex PTSD and DSM-5 BPD commonly co-occurred but were not the same construct in the Asian context, and their symptoms were associated with different sets of demographic and clinical factors. Future editions of DSM and ICD should not merge the two conditions into a single diagnosis.

9.
Chemosphere ; 364: 143236, 2024 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-39222690

RESUMO

The misuse and inevitable release of antibiotics can cause significant harm to both human health and the environment, and the use of polymeric semiconductors for photodegradation of antibiotics in aqueous environments is one of the most effective strategies to alleviate the current dilemma. Nevertheless, the inherently high exciton binding energy (Eb) and low photogenerated carrier transfer efficiency for most photocatalysts results in unsatisfactory photodegradation performance. Hence, this work proposes a donor polarization strategy to regulate the exciton dissociation of conjugated microporous polymers (CMPs) by minimizing their Eb. Results exhibited that the introduction of the strong donor unit 3,4-ethylenedioxythiophene (EDOT) not only reduces the Eb and effectively promotes exciton dissociation, but also broadens the visible light absorption of CMP. Among them, EdtTz-CMP with the lowest Eb (99 meV) delivered an efficiency of 94.6% in photocatalytic degradation of tetracycline (TC) with in 90 min, significantly higher than those of its analogues. This work provides a viable approach to design CMPs by tuning the intrinsic dipole of the donor for efficient environmental purification.

10.
Angew Chem Int Ed Engl ; : e202415726, 2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-39240581

RESUMO

The electrochemical CO2 reduction reaction (ECR) is a promising pathway to producing valuable chemicals and fuels. Despite extensive studies reported, improving CO2 adsorption for local CO2 enrichment or water dissociation to generate sufficient H* is still not enough to achieve industrial-relevant current densities. Herein, we report a "two-in-one" catalyst, defective Bi nanosheets modified by CrOx (Bi-CrOx), to simultaneously promote CO2 adsorption and water dissociation, thereby enhancing the activity and selectivity of ECR to formate. The Bi-CrOx exhibits an excellent Faradic efficiency (≈ 100 %) in a wide potential range from ‒0.4 to ‒0.9 V. In addition, it achieves a remarkable formate partial current density of 687 mA cm‒2 at a moderate potential of ‒0.9 V without iR compensation, the highest value at ‒0.9 V reported so far. Control experiments and theoretical simulations revealed that the defective Bi facilitates CO2 adsorption/activation while the CrOx accounts for enhancing the protonation process via accelerating H2O dissociation. This work presents a pathway to boosting formate production through tuning CO2 and H2O species at the same time.

11.
Bioanalysis ; : 1-11, 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39262387

RESUMO

Aim: This study aims to compare the anti-drug antibody (ADA) interference in four pharmacokinetic (PK) assays across different platforms (AlphaLISA, Gyrolab, LC-MS/MS) and to devise a strategy for ADA interference mitigation to improve the accuracy of measured drug in total PK assays.Materials & methods: Spiked test samples, created to achieve different ADA concentrations in human serum also containing an insulin analogue, were analyzed alongside pooled clinical samples using four assays.Results & conclusion: Interference was observed in all platforms. A novel approach using the Gyrolab mixing CD, including acid dissociation in the PK assay, significantly reduced interference and thereby improved relative error from >99% to ≤20% yielding measurements well within the acceptance criteria. Clinical sample results reinforced findings from the test samples.


[Box: see text].

12.
Bio Protoc ; 14(15): e5041, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-39131194

RESUMO

Microscale thermophoresis (MST) is a technique used to measure the strength of molecular interactions. MST is a thermophoretic-based technique that monitors the change in fluorescence associated with the movement of fluorescent-labeled molecules in response to a temperature gradient triggered by an IR LASER. MST has advantages over other approaches for examining molecular interactions, such as isothermal titration calorimetry, nuclear magnetic resonance, biolayer interferometry, and surface plasmon resonance, requiring a small sample size that does not need to be immobilized and a high-sensitivity fluorescence detection. In addition, since the approach involves the loading of samples into capillaries that can be easily sealed, it can be adapted to analyze oxygen-sensitive samples. In this Bio-protocol, we describe the troubleshooting and optimization we have done to enable the use of MST to examine protein-protein interactions, protein-ligand interactions, and protein-nanocrystal interactions. The salient elements in the developed procedures include 1) loading and sealing capabilities in an anaerobic chamber for analysis using a NanoTemper MST located on the benchtop in air, 2) identification of the optimal reducing agents compatible with data acquisition with effective protection against trace oxygen, and 3) the optimization of data acquisition and analysis procedures. The procedures lay the groundwork to define the determinants of molecular interactions in these technically demanding systems. Key features • Established procedures for loading and sealing tubes in an anaerobic chamber for subsequent analysis. • Sodium dithionite (NaDT) could easily be substituted with one electron-reduced 1,1'-bis(3-sulfonatopropyl)-4,4'-bipyridinium [(SPr)2V•] to perform sensitive biophysical assays on oxygen-sensitive proteins like the MoFe protein. • Established MST as an experimental tool to quantify binding affinities in novel enzyme-quantum dot biohybrid complexes that are extremely oxygen-sensitive.

13.
Neurocrit Care ; 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39138716

RESUMO

BACKGROUND: Brain activation to motor commands is seen in 15% of clinically unresponsive patients with acute brain injury. This state called cognitive motor dissociation (CMD) is detectable by electroencephalogram (EEG) or functional magnetic resonance imaging, predicts long-term recovery, and is recommended by recent guidelines to support prognostication. However, false negative CMD results are a particular concern, and occult aphasia in clinically unresponsive patients may be a major factor. This study aimed to quantify the impact of aphasia on CMD testing. METHODS: We prospectively studied 61 intensive care unit patients admitted with acute primary intracerebral hemorrhage (ICH) who had behavioral evidence of command following or were able to mimic motor commands. All patients underwent an EEG-based motor command paradigm used to detect CMD and comprehensive aphasia assessments. Logistic regression was used to identify predictors of brain activation, including aphasia types and associations with recovery of independence (Glasgow Outcome Scale-Extended score ≥ 4). RESULTS: Of 61 patients, 50 completed aphasia and the EEG-based motor command paradigm. A total of 72% (n = 36) were diagnosed with aphasia. Patients with impaired comprehension (i.e., receptive or global aphasia) were less likely to show brain activation than those with intact comprehension (odds ratio [OR] 0.23 [95% confidence interval 0.05-0.89], p = 0.04). Brain activation was independently associated with Glasgow Outcome Scale-Extended ≥ 4 by 12 months (OR 2.4 [95% confidence interval 1.2-5.0], p = 0.01) accounting for the Functional Outcome in Patients with Primary ICH score (OR1.3 [95% confidence interval 1.0-1.8], p = 0.01). CONCLUSIONS: Brain activation to motor commands is four times less likely for patients with primary ICH with impaired comprehension. False negative results due to occult receptive aphasia need to be considered when interpreting CMD testing. Early detection of brain activation may help predict long-term recovery in conscious patients with ICH.

14.
Front Psychol ; 15: 1394014, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39105148

RESUMO

Introduction: The Global Psychotrauma Screen (GPS) is a brief transdiagnostic screener that covers a broad range of trauma-related disorders as well as risk factors known to influence the course of symptoms. Methods: We analyzed data from African war refugees in Australia (n = 70), including the GPS, the Structured Clinical Interview for DSM-5 Disorders (SCID-5), the Clinician-Administered PTSD Scale for DSM-5 (CAPS-5), and the Brief Resilience Scale (BRS). Results: Using the Youden's J Index to examine the clinical validity of the GPS subscales measuring PTSD, dissociation, depression, and generalized anxiety disorder (GAD), we found that a PTSD subscale score of 3 or higher, and a depression and dissociation subscale score of 1 or higher, was optimally efficient for detecting a probable diagnosis (Youden's J = 0.76, J = 0.72, and J = 0.90, respectively) with high sensitivity and specificity. We were unable to test the GPS clinical validity for GAD due to the low GAD occurrence. The GPS resilience item was not related to the total score (r = 0.02), indicating low convergent validity for resilience. Risk factors, including current stressors and childhood trauma history, were related to more severe GPS symptom scores, while lack of resilience, social support, and history of mental illness were not. Conclusion: We conclude that the GPS may be a useful screening tool for PTSD, depression, and the dissociative subtype in refugees.

15.
Sci Rep ; 14(1): 18115, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-39103460

RESUMO

The mechanism of Y on H/H2 adsorption performance of Mg17Al12 were studied by the density functional theory. We obtained that for the Y-adsorbed systems, Y tended to occupy on the bridge site between adjacent Mg atoms. For the Y-substituted surfaces, Y atoms inclined to replace Mg atoms on the surfaces. We found that hydrogen (H/H2) absorption on the Mg17Al12(110) systems were improved by adding Y, the order of adsorption energy was as follows: clean Mg17Al12(110) > the Y-substituted surfaces > the Y-adsorbed surfaces. In addition, H2 molecules could dissociate on the Y-containing systems without barrier energy. Electronic properties showed that for H2 adsorption, the s states of atomic H mainly hybridized with the d states of Y. The formations of the Y-H bonds and the interactions between Y and H atoms could expound the mechanism for the promoted hydrogenation performance of the Y-containing surfaces.

16.
Anal Chim Acta ; 1319: 342949, 2024 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-39122291

RESUMO

BACKGROUND: Synthetic cathinones (SCs) are a large category of new psychoactive substances (NPS), which pose a serious threat to public health due to limited information about their toxicology and pharmacology. Many SCs are closely related in their chemical structures, with some substances being positional isomers. In this study, we propose a new workflow for the identification of SC isomers using liquid chromatography-high-resolution tandem mass spectrometry (LC-HRMS2) combined with electron activated dissociation (EAD) and chemometrics. Differentiation between isomeric SCs is essential for both legislative and public safety reasons, since minor differences in their molecular structures may change their legal status and pharmacological profiles. RESULTS: The workflow was optimized using ring-substituted isomers of methylmethcathinones, methylethcathinones, and chloromethcathinones. The kinetic energy in the EAD cell was investigated at three levels (i.e., 15, 18, and 20 eV) for each group. Two data analysis methods (i.e., t-distributed stochastic neighbor embedding [t-SNE] and a Random Forest [RF] algorithm) were applied using the obtained EAD mass spectral data. The three sets of ring-substituted SCs were clearly distinguished using t-SNE and an RF algorithm. Moreover, the RF approach resulted in a 97 % classification accuracy for isomer identification using various combinations of compounds, isomers, and electron kinetic energies. This workflow was subsequentially applied to the analysis of 26 blind street samples, resulting in a 92 % classification accuracy for isomer identification. However, the accuracy varied based on the kinetic electron energy. A subset of the original data set, focusing on 15-eV data only, was used, resulting in a classification accuracy of 100 %. SIGNIFICANCE: This study presents the first LC-HRMS2 workflow based on EAD and chemometrics, which resulted in a classification accuracy of 100 % of authentic street samples. The developed LC-HRMS2 workflow demonstrates that EAD product ions and their characteristic ion ratios can be successfully used to identify ring-substituted positional isomers of SCs.

17.
J Colloid Interface Sci ; 677(Pt A): 831-841, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-39126801

RESUMO

Photocatalytic nitrogen reduction reaction (NRR) is a sustainable process for ammonia synthesis under mild conditions. However, photocatalytic NRR activity and are generally limited by inefficient carrier separation and transfer. Therefore, parallel engineering of bulk phase doping and surface coupling is critical to achieving the goal of efficient NRR. In this study, Cl doped BiOBr nanosheet assemblies (BiOBr/Cl) were constructed in delicately designed deep eutectic solvents (DESs), combined with ionothermal methods at low temperatures and Bi3+ exsolution reduction strategy at high temperatures. The unique liquid state and reducibility of DESs induce the reduction of Bi3+ and the in situ coupling of Bi quantum dots at the surface of BiOBr/Cl nanosheets along with the construction of Bi-BiOBr/Cl nanosheet assemblies. The experimental results show that Cl doping could reduce the exciton dissociation energy and promote its dissociation to free carriers. Bi quantum dots could form tightly coupled Schottky junction with BiOBr/Cl enabling the efficient and unidirectional transmission of photogenerated electrons from BiOBr/Cl to metal Bi. The formed electron deficient region at Schottky interface promotes the adsorption and activation of N2. The hierarchical structure of Bi-BiOBr/Cl nanosheet assembly benefits to providing more N2 adsorption active sites. The DFT calculation shows that the accumulation of high concentration of active hydrogen in Bi-BiOBr/Cl leads to a significant decrease of energy barrier of the first step hydrogenation of N2. Bi-BiOBr/Clis more inclined to adsorb nitrogen for NRR in comparison with H* for hydrogen production. The synergistic effect of Cl doping and Bi coupling result in a high NRR activity of Bi-BiOBr/Cl photocatalyst of 6.67 mmol·g-1·h-1, which was 11.3 times higher than that of initial BiOBr. This study provides a promising strategy for designing highly active NRR photocatalysts with high efficiency carrier dissociation and transport.

18.
J Trauma Dissociation ; : 1-15, 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39093625

RESUMO

The first purpose of this study was to determine the course of dissociation among patients with borderline personality disorder (BPD) and personality-disordered comparison subjects (OPD) over 24 years of prospective follow-up. The second purpose was to determine clinically meaningful predictors of dissociation among patients with BPD. The Dissociative Experiences Scale (DES) was administered to 290 patients with BPD and 72 personality-disordered comparison subjects at baseline, and then once every two years over 24 years of prospective follow-up. Baseline predictors were assessed with the Revised Childhood Experiences Questionnaire (CEQ-R), the SCID-I, and the Shipley Institute of Living Scale. Time-varying predictors were assessed at baseline and every subsequent two years by means of the Abuse History Interview (AHI). Patients with BPD had higher baseline dissociation scores than personality-disordered comparison subjects. Whilst dissociation decreased significantly over time for both patient groups, the BPD group showed a steeper decline. Severity of childhood sexual abuse, adult history of rape, adult history of partner violence, and IQ were multivariate predictors of dissociation among patients with BPD. Taken together, the present findings suggest that a combination of interpersonal trauma exposure and cognitive abilities may contribute to the severity of dissociation in adult patients with BPD.

19.
J Mass Spectrom ; 59(9): e5079, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39132903

RESUMO

Triphenylamine (TPA) and N-heterotriangulene (N-HTA) scaffolds with up to three oligophenyl extensions are investigated by electrospray ionization (tandem) mass spectrometry (ESI-[MS/]MS). Due to their low oxidation potentials, all molecules readily form radical cations in the electrospray process. The energy-resolved collision-induced dissociation behaviour of the molecular ions is contrasted to that of the silver(I) adducts. Complexation with Ag(I) leads to the expected [1:1] and [2:1] complexes (MAg+ and M2Ag+); however, even [1:2] complexes (MAg2 2+) can be detected for molecules with two and three large π-expansions to allow stabilization of two charges. The TPA scaffolds decompose only at high collision energies through the loss of peripheral tert-butyl groups. A general mechanism for this is proposed commencing with a methyl loss and followed by the release of isobutene and butyl radical moieties. The N-HTA-based scaffolds are considerably less stable and molecular ions fragment at low collision energies. This is caused by the facile loss of methyl radicals from the dimethylmethylene-bridged triangulene core. In contrast, complexation with Ag+ leads to a dramatic stabilization. Most interestingly, dissociation eventually proceeds via the loss of neutral AgCH3, which is indicative of strong bidentate, tweezer-like bonding of Ag+ to the molecules.

20.
J Mass Spectrom ; 59(9): e5078, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39132905

RESUMO

Understanding fungal lipid biology and metabolism is critical for antifungal target discovery as lipids play central roles in cellular processes. Nuances in lipid structural differences can significantly impact their functions, making it necessary to characterize lipids in detail to understand their roles in these complex systems. In particular, lipid double bond (DB) locations are an important component of lipid structure that can only be determined using a few specialized analytical techniques. Ozone-induced dissociation mass spectrometry (OzID-MS) is one such technique that uses ozone to break lipid DBs, producing pairs of characteristic fragments that allow the determination of DB positions. In this work, we apply OzID-MS and LipidOz software to analyze the complex lipids of Saccharomyces cerevisiae yeast strains transformed with different fatty acid desaturases from Histoplasma capsulatum to determine the specific unsaturated lipids produced. The automated data analysis in LipidOz made the determination of DB positions from this large dataset more practical, but manual verification for all targets was still time-consuming. The DL model reduces manual involvement in data analysis, but since it was trained using mammalian lipid extracts, the prediction accuracy on yeast-derived data was reduced. We addressed both shortcomings by retraining the DL model to act as a pre-filter to prioritize targets for automated analysis, providing confident manually verified results but requiring less computational time and manual effort. Our workflow resulted in the determination of detailed DB positions and enzymatic specificity.


Assuntos
Aprendizado Profundo , Ozônio , Saccharomyces cerevisiae , Fluxo de Trabalho , Saccharomyces cerevisiae/química , Ozônio/química , Histoplasma/química , Histoplasma/metabolismo , Espectrometria de Massas/métodos , Software , Ácidos Graxos Insaturados/química , Ácidos Graxos Insaturados/análise , Ácidos Graxos Insaturados/metabolismo , Ácidos Graxos/química , Ácidos Graxos/análise , Ácidos Graxos/metabolismo , Lipídeos/química
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