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Magdalena Marczak

Publications and source records attributed to Magdalena Marczak.

5 recordsLinked to original sources
PubMed2026

Antegrade dissection and re-entry vs retrograde strategy in chronic total occlusion percutaneous coronary intervention: Rationale and design of the ADRENALINE randomized study.

RATIONALE: While antegrade wiring (AW) is the most common initial strategy for chronic total occlusion (CTO) percutaneous coronary intervention (PCI), difficult CTO lesions frequently require either antegrade dissection and re-entry (ADR) or a retrograde strategy. Comparative data between ADR and the retrograde approach remain limited. DESIGN: The Antegrade Dissection vs Retrograde re-ENtry And Load of Interventionalist Effort (ADRENALINE) is a prospective, multicenter randomized study with a superiority design. It is planned to enroll 121 patients with difficult coronary CTO (J-CTO score ≥2) referred for CTO-PCI in accordance with the hybrid algorithm. Subjects undergoing successful AW will be included in the observational arm. Patients with failed or unattempted AW will be randomized 1:1 to ADR or retrograde CTO crossing strategy (n = 74). All patients will undergo pre- and postprocedural laboratory testing (including cardiac troponin T and creatine kinase-MB), cardiac magnetic resonance (CMR) for late gadolinium enhancement, and health status assessment by the Seattle Angina Questionnaire and the Rose Dyspnea Scale. The co-primary endpoints are total procedure time and successful guidewire crossing. Additionally, the relationship between different recanalization strategies and stress among interventional cardiologists will be explored. CONCLUSION: ADRENALINE is the first randomized study of ADR vs retrograde strategy for difficult CTO PCI, assessing procedural outcomes, CMR-detected myocardial infarction, and 3-month quality of life. ENROLMENT STATUS: The first patient was enrolled on July 29, 2025. As of June 14, 2026, 45 patients (26 randomized, 19 observational) of the planned 121 patients have been enrolled. TRIALS REGISTRATION: Clinicaltrials.gov: Identifier, NCT06878729.

Humans↗
PubMedDate not supplied

Augmentation of Hypoxic Respiration after Brief Hyperoxia in the Anesthetized Cat: Putative Function of GABA(A) Neurotransmission.

In this study, we attempted to determine the role of GABA neurotransmission in augmentation of hypoxic respiration by antecedent hyperoxic breathing. The experiments were performed in anesthetized, paralyzed and vagotomized cats divided into control and bicuculline (a GABA(A) receptor blocker)-injected groups. The experimental protocol consisted of exposing the animals to successive hypoxic-hyperoxic-hypoxic conditions. Respiration was assessed using phrenic electroneurograms, from which the peak phrenic height, a surrogate of the tidal volume component, and respiratory rate were obtained, and their product, the respiratory minute output, was calculated. We found that prior hyperoxic ventilation increased the subsequent respiratory response to hypoxia by an average of 23.5%, compared with the preoxygen response. This increase was driven by volume respiration. The biphasic character of the hypoxic respiratory response, consisting of stimulatory and depressant phases, was sustained. Bicuculline abolished the augmentative effect on hypoxic respiration of prior hyperoxia, which suggests that oxygenation induces GABA(A)-mediated hyperexcitability of respiratory neurons, possibly by the liberation of reactive oxygen species. We concluded that GABA neurotransmission is pertinent to the effect of hyperoxia on hypoxic respiratory reactivity.

Animals↗
PubMedDate not supplied

Ascorbyl palmitate as a carrier of ascorbate into neural tissues.

We have investigated the hypothesis that a lipid-soluble derivative of ascorbic acid, ascorbyl-6-palmitate (AP), could serve as a carrier of ascorbate into neural tissues. Ascorbate could then exert its physiological effects in the biomembranes that are the target sites of the cellular signaling pathways which are normally hardly accessible to this water-soluble compound. The potential role of AP would require that it penetrates into tissues. The major objective of the study was to determine whether ascorbate could be recovered from cerebral cortex and carotid body tissues, both sensitive to the hypoxic stimulus, after AP given by gavage. Biological samples were analyzed by HPLC for the determination of ascorbate. We found that ascorbate was recovered from the tissues studied. Its content was higher in both tissues, by nearly an order of magnitude, after ingestion of AP than after ingestion of ascorbic acid, and the ascorbate level was higher in the carotid body than in the cortex. Hypoxia decreased the ascorbate content which implies physiological activity of ascorbate carried alongside the AP molecule. The lipophilic AP was able to cross biological barriers and satisfied the tissue demand for ascorbate better than the hydrophilic form. AP should be considered as the preferred form of transport of ascorbate into neural tissues. The results of this study suggest wider pharmacological applications of ascorbyl palmitate.

Animals↗
PubMedDate not supplied

Ascorbyl palmitate augments hypoxic respiratory response in the cat.

The redox signaling is germane for the hypoxia-sensing mechanisms at the carotid body. This raises the strong possibility that agents possess reducing and antioxidant attributes, such as ascorbate, could influence the hypoxic respiratory response. However, water solubility of ascorbate makes its effectiveness at membrane-associated target sites dubious. In this study, we sought to determine the effect of ascorbyl-6-palmitate (AP), a lipid-soluble derivative of ascorbate which penetrates biomembranes, on hypoxic respiration in the anesthetized, paralyzed and ventilated cat. AP was given by gavage: 600 mg/kg daily for 6 days before the beginning of the acute experiment. Respiration was then assessed from the phrenic electroneurogram, from which peak phrenic amplitude, a surrogate of tidal component, respiratory frequency, and their product, the minute phrenic output, were quantified. The response to normocapnic hypoxia, 7% O(2) in N(2), in the AP-treated cats was compared with that in controls. We found that AP augmented hypoxic respiration, delayed the appearance of hypoxic depression and decreased it, although the stimulatory/depressant character was preserved. The results suggest that the ascorbate moiety of AP interacts with the hypoxia-sensing mechanisms. Ascorbate may affect hypoxic respiration at multiple stages of chemotransduction pathways, which are subject to continuing uncertainties. The study highlights the augmentative effect of AP, a redox modulator, on hypoxic respiration, which may have a therapeutic potential.

Animals↗