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1.
Sensors (Basel) ; 24(14)2024 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-39065927

RESUMEN

Zn2+ has a crucial role both in biology and the environment, while Pb2+ presents serious hazards in the same areas due to its toxicity, and the need for their analysis often exceeds available instrumental capacity. We report, herein, a new high-throughput optochemical screening method for Zn2+ and Pb2+ in various solutions. Moreover, we also introduced a new and generalizable three-step-microplate-modification technique, including plasma treating, linker-docking and photocatalytic copolymerization. The surface of a commercially available 96-well-cycloolefin-microplate was treated with atmospheric plasma, and then, the bottoms of the wells were covered by covalently attaching a methacrylate-containing linker-monolayer. Finally, the preactivated microplate wells were covalently functionalized by immobilizing bis(acridino)-crown ether-type sensor molecules, via photocatalytic copolymerization, to a polymethacrylate backbone. This sensing tool can be used in all microplate readers, is compatible with liquid handling platforms and provides an unprecedently fast monitoring (>1000 samples/hour, extrapolated from the time required for 96 measurements) of dissolved Zn2+ and Pb2+ among recent alternatives above the detection limits of 8.0 × 10-9 and 3.0 × 10-8 mol/L, respectively, while requiring a sample volume of only 20 µL.

2.
Medicina (Kaunas) ; 58(8)2022 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-36013515

RESUMEN

Background and Objectives: Early repolarization pattern (ERP) has recently been shown to be related with an increased risk of ventricular arrhythmias in susceptible individuals. Materials and Methods: We studied the ERP-associated ECG changes, with potential clinical relevance, in 220 young (age 22.1 ± 1.6 years), healthy, male subjects using 12-lead ECG recordings. A total of 38 subjects (17.3%) fulfilled the diagnostic criteria for ERP, and a total of 90 ECG characteristics were compared between the groups of subjects with and without ERP. Results: None of the ECGs were pathological, and 22 ECG parameters differed significantly (p < 0.05) between the subjects with and without ERP. Among them, the P wave-related parameters (e.g., average P wave duration: 101.5 ± 9.2 ms vs. 106.8 ± 9.9 ms, p = 0.004) and the presence of fragmented QRS complexes (67.6% vs. 92.1%, p = 0.002) revealed a potential propensity for atrial and ventricular arrhythmogenesis. The time-domain parameters of repolarization, those not corrected for QRS duration, showed shorter values (e.g., Tpeak-Tend interval: 70.9 ± 8.1 ms vs. 67.8 ± 8.0 ms, p = 0.036), reflecting the accelerated repolarization. Conclusions: Certain ECG characteristics seem to be more associated with ERP. The clinical significance of this finding at the individual level needs further prospective investigations.


Asunto(s)
Arritmias Cardíacas , Electrocardiografía , Adulto , Arritmias Cardíacas/diagnóstico , Humanos , Masculino , Adulto Joven
3.
Diagnostics (Basel) ; 14(10)2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38786277

RESUMEN

Background: Exercise-induced modifications in ECG parameters among individuals with an early repolarization pattern (ERP) have not been evaluated in detail. We aimed to assess this phenomenon, with potential associations with arrhythmogenesis. Methods: Twenty-three young, healthy males with ERP (ERP+) participated in this study, alongside a control group, which consisted of nineteen healthy males without ERP (ERP-). ECGs at baseline, at peak exercise (Bruce protocol), and during the recovery phase were analyzed and compared between the two groups. Results: The treadmill test demonstrated strong cardiovascular fitness, with similar chronotropic and pressor responses in both groups. In the baseline ECGs, the QRS complex and the QT interval were shorter in the ERP+ group. During exercise, the P-wave duration was significantly longer and the QRS was narrower in the ERP+ group. In the recovery phase, there was a longer P wave and a narrower QRS in the ERP+ group. During the treadmill test, the J wave disappeared or did not meet the criteria required for ERP diagnosis. Conclusions: The slowed intra-atrial conduction found during exercise could be predictive of atrial arrhythmogenesis in the setting of ERP. The disappearing of J waves during exercise, due to increased sympathetic activity, has potential clinical significance.

4.
Front Physiol ; 14: 1180896, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37351262

RESUMEN

Introduction: Previous studies have established that endogenous inorganic polysulfides have significant biological actions activating the Transient Receptor Potential Ankyrin 1 (TRPA1) receptor. Organic polysulfides exert similar effects, but they are much more stable molecules, therefore these compounds are more suitable as drugs. In this study, we aimed to better understand the mechanism of action of organic polysulfides by identification of their binding site on the TRPA1 receptor. Methods: Polysulfides can readily interact with the thiol side chain of the cysteine residues of the protein. To investigate their role in the TRPA1 activation, we replaced several cysteine residues by alanine via site-directed mutagenesis. We searched for TRPA1 mutant variants with decreased or lost activating effect of the polysulfides, but with other functions remaining intact (such as the effects of non-electrophilic agonists and antagonists). The binding properties of the mutant receptors were analyzed by in silico molecular docking. Functional changes were tested by in vitro methods: calcium sensitive fluorescent flow cytometry, whole-cell patch-clamp and radioactive calcium-45 liquid scintillation counting. Results: The cysteines forming the conventional binding site of electrophilic agonists, namely C621, C641 and C665 also bind the organic polysulfides, with the key role of C621. However, only their combined mutation abolished completely the organic polysulfide-induced activation of the receptor. Discussion: Since previous papers provided evidence that organic polysulfides exert analgesic and anti-inflammatory actions in different in vivo animal models, we anticipate that the development of TRPA1-targeted, organic polysulfide-based drugs will be promoted by this identification of the binding site.

5.
Pharmaceuticals (Basel) ; 15(10)2022 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-36297294

RESUMEN

There is an unmet need for novel therapeutic tools relieving chronic pain. Hydrogen sulfide (H2S) is highly involved in pain processes; however, the development of ideal matrices for sulfide donor compounds remains a great pharmaceutical challenge. We aimed to establish a suitable transdermal therapeutic system (TTS) using the H2S donor diallyl disulfide (DADS) as a model compound. After the preparation of DADS, its solubility was investigated in different liquid excipients (propylene glycol, polyethylene glycol, silicone oil) and its membrane diffusivity was assessed in silicone matrices of different compositions. Drug-releasing properties of DADS-containing patches with different silicone oil contents were determined with Franz and flow-through cells. We found a correlation between the liquid excipient content of the patch and the diffusion rate of DADS. DADS showed the best solubility in dimethyl silicone oil, and the diffusion constant was proportional to the amount of oil above the 3 m/m% threshold value. The 8-day-old patch showed a significantly lower, but better-regulated, drug release over time than the 4-day-old one. In conclusion, the silicone-based polymer matrix developed in this study is suitable for stable storage and optimal release of DADS, providing a good basis for a TTS applied in chronic pain.

6.
Pharmaceuticals (Basel) ; 15(10)2022 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-36297391

RESUMEN

Transdermal therapeutic systems (TTSs) enable convenient dosing in drug therapy. Modified silicone-polymer-based patches are well-controlled and cost-effective matrix diffusion systems. In the present study, we investigated the substance release properties, skin penetration, and analgesic effect of this type of TTS loaded with low-dose capsaicin. Release properties were measured in Franz diffusion cell and continuous flow-through cell approaches. Capsaicin was detected with HPLC-UV and UV spectrophotometry. Raman spectroscopy was conducted on human skin samples exposed to the TTS. A surgical incision or carrageenan injection was performed on one hind paw of male Wistar rats. TTSs were applied to the epilated dorsal skin. Patches were kept on the animals for 6 h. The thermal hyperalgesia and mechanical pain threshold of the hind paws were detected. Patches exhibited controlled, zero-order kinetic capsaicin release. According to the Raman mapping, capsaicin penetrated into the epidermis and dermis of human skin, where the target receptors are expressed. The thermal pain threshold drop of the operated rat paws was reversed by capsaicin treatment compared to that of animals treated with control patches. It was concluded that our modified silicone-polymer-based capsaicin-containing TTS is suitable for the relief of traumatic and inflammatory pain.

7.
Orv Hetil ; 162(19): 741-745, 2021 05 09.
Artículo en Húngaro | MEDLINE | ID: mdl-33965908

RESUMEN

Összefoglaló. Bevezetés: Az EKG-n megjeleno korai repolarizációs mintázat diagnosztikai kritériumai és klinikai jelentosége elsosorban az elmúlt évtizedben került tisztázásra, ugyanakkor viszonylag kevés vizsgálat foglalkozott mind ez idáig a korai repolarizációs mintázathoz kötheto esetleges strukturális szívelváltozások felderítésével. Módszer: Egy prospektív vizsgálat során azonosított 30, korai repolarizációs mintázatot mutató fiatal férfi (átlagéletkor: 22,5 ± 1,5 év) echokardiográfiás paramétereit hasonlítottuk össze egy 32 fobol álló (átlagéletkor: 22,3 ± 1,9 év) megfeleltetett kontrollcsoport azonos jellemzoivel. A hagyományos paraméterek mérésén túlmenoen, szöveti Doppler- és 'strain' (deformáció - speckle tracking módszerrel) vizsgálatot is végeztünk, összesen 35 jellemzot követve. A paraméterek összehasonlítása kétmintás t-próba, illetve khi-négyzet-próba segítségével történt (szignifikancia: p<0,05). Eredmények: Nem találtunk patológiás elváltozásokat egyik személy esetében sem, és a két csoport között csupán két paraméter tekintetében fedeztünk fel szignifikáns eltérést. A korai repolarizációs mintázatot mutató csoportban kisebbnek bizonyult a bal kamra végsystolés térfogata (37,6 ± 15,2 ml vs. 45,5 ± 13,4 ml; p = 0,037), illetve gyakoribbnak találtuk az enyhe mitralis regurgitatio elofordulását (41,4% vs. 6,5%; p<0,001). Következtetés: A korai repolarizációs mintázatot mutató fiatal férfiak esetén kimutathatók bizonyos echokardiográfiás jellegzetességek. Ezek idobeli alakulásának, illetve prognosztikai, aritmológiai jelentoségének megítélése további, longitudinális követést igényel. Orv Hetil. 2021; 162(19): 741-745. INTRODUCTION: The diagnostic criteria and clinical significance of early repolarization pattern on ECG were clarified mainly in the last decade. However, there are only a few studies published on the exploration of cardiac structural changes underlying early repolarization pattern. METHOD: We compared the echocardiographic parameters of 30 young males with early repolarization pattern (mean age: 22.5 ± 1.5 years), who were identified during a prospective survey, with the same parameters of a matched control group consisting of 32 young males (mean age: 22.3 ± 1.9 years). Beyond measuring the conventional parameters, tissue Doppler and strain measures (speckle tracking) were obtained. Comparison of parameters was performed using t-test and chi-square test (significancy: p<0.05). RESULTS: There were no pathological changes in any person, and we found significant difference between the two groups only in the case of two parameters. In the early repolarization pattern group, the left ventricular end-systolic volume was smaller (37.6 ± 15.2 ml vs. 45.5 ± 13.4 ml; p = 0.037) and the presence of mild mitral regurgitation was more frequent (41.4% vs. 6.5%; p<0.001). CONCLUSION: In young males with early repolarization pattern, we managed to demonstrate the existence of certain echocardiographic features. The assessment of their time course, prognostic and arrhythmological significance requires a longer follow-up. Orv Hetil. 2021; 162(19): 741-745.


Asunto(s)
Ecocardiografía , Adulto , Humanos , Masculino , Pronóstico , Estudios Prospectivos , Adulto Joven
8.
Magy Seb ; 56(1): 17-24, 2003 Feb.
Artículo en Húngaro | MEDLINE | ID: mdl-12764988

RESUMEN

The understanding, complex analysis and extensive knowledge about the physiology of the gastrointestinal tract are bases of functional and reconstructive surgery. We present our routine physiological tests. Several clinical syndromes may be related to motility disorders of the esophagus, stomach, colon and the anal sphincter apparatus. We show how functional tests influence surgery. Preoperative pH monitoring and esophageal manometry are essential in the planning of surgical treatment of GORD. The lower gastrointestinal functional tests help in the treatment of anal incontinence. Screening of the anal sphincter helps in the decision when to close non permanent stomas, and the inspection benefits haemorrhoidectomies on patients with poor anal sphincter status. We are present our initial practice with the functional tests.


Asunto(s)
Procedimientos Quirúrgicos del Sistema Digestivo , Enfermedades Gastrointestinales/fisiopatología , Enfermedades Gastrointestinales/cirugía , Manometría , Adulto , Anciano , Incontinencia Fecal/fisiopatología , Incontinencia Fecal/cirugía , Femenino , Reflujo Gastroesofágico/fisiopatología , Reflujo Gastroesofágico/cirugía , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios Retrospectivos
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