Preventing cancer therapy-related heart failure: the need for novel studies.

AIMS: After enhancing the survivorship of cancers, the impact of cardiovascular diseases on mortality is increasing among cancer patients. However, anticancer therapies pose a higher cardiovascular risk to patients. As prevention against cancer therapy-induced cardiomyopathy has yet to be explored, the preventive ability of concomitant cardiovascular medications against incident heart failure was assessed. METHODS: A retrospective, population-based study was run using anonymized integration of healthcare databases. All the Hungarian patients diagnosed with breast or colorectal carcinoma and undergoing chemotherapy or biological therapy were analysed. Participants were not treated with any anticancer therapy nor suffered from heart failure/dilated cardiomyopathy during the preceding observational period (≥6.5 years). The heart failure endpoint was established by I50 International Classification of Diseases codes upon discharge from hospital or issuance of an autopsy report. RESULTS: Among the 9575 patients who were enrolled, the cumulative incidence of heart failure over 4 years was 6.9%. The time until the first heart failure event in the propensity score-matched treated and untreated groups was compared using Cox proportional-hazards models. A significant association between lower heart failure risk and concomitant statin therapy was observed (hazard ratio: 0.748, P = 0.038); the preventive ability was more pronounced in the anthracycline/capecitabine/platinum-treated subgroup (hazard ratio: 0.660, P = 0.032). For angiotensin-converting enzyme inhibitor/angiotensin II receptor blocker therapy, a significantly lower heart failure risk was also observed (hazard ratio: 0.809, P = 0.032). Among beta blockers, nebivolol administered to anthracycline/capecitabine-treated patients was associated with a nonsignificant trend to lower heart failure risk (hazard ratio: 0.584, P = 0.069). CONCLUSION: Only concomitant statin and angiotensin-converting enzyme inhibitor/angiotensin II receptor blocker therapies were associated with significantly lower risk of anticancer therapy-related heart failure.

Faecal microbiota transfer in patients with microscopic colitis - a pilot study in collagenous colitis.

OBJECTIVES: Faecal microbiota transfer (FMT) consists of the infusion of donor faecal material into the intestine of patients with the aim to restore a disturbed gut microbiota. METHODS: In this pilot study (NCT03275467), the effect of three repeated FMTs (day 0, two weeks, four weeks) was studied and followed up for six months in nine collagenous colitis (CC) patients, using two stool donors. RESULTS: Five patients had an active disease at the time of baseline sampling. The primary endpoint (remission at six weeks, defined as <3 stools whereof <1 watery stool per day) was achieved by two of these patients, and by one at eight weeks. Overall, in all nine patients, FMT did not result in a significant reduction of watery stools, assessed by daily diary. However, diarrhoea (assessed by gastrointestinal symptom rating scale) was significantly improved at four (p = .038) and eight weeks (p = .038), indigestion at eight (p = .045) and 12 weeks (p = .006), disease-related worries at four (p = .027) and eight weeks (p = .027), and quality of life at six months (p = .009). FMT resulted in an increased number of lamina propria lymphocytes, possibly indicating an initial mucosal immune activation. No serious adverse events, no systemic effects, and no changes in faecal calprotectin and psychological symptoms were observed. CONCLUSIONS: FMT is able to improve symptoms in a yet undefined subset of CC patients. Further studies could help to characterise this subset and to understand if these results can be generalised to all microscopic colitis patients.

Analysing the risk factors of doxorubicin-associated heart failure by a retrospective study of integrated, nation-wide databases / A doxorubicinkezeléshez kapcsolódó szívelégtelenség kialakulásának rizikótényezoi a hazai országos adatbázisok integrált, retrospektív elemzése alapján

INTRODUCTION: The incidence of dilated cardiomyopathy after anthracycline chemotherapy is mainly influenced by anthracycline cumulative dose. Previous researches showed doxorubicin treatment under cumulative dose of 450 mg/m2 associated with a low incidence of heart failure. Nowadays, doxorubicin is administered with a lower dose, the development of heart failure is largely determined by other factors. AIM: Our purpose was to identify the risk factors for heart failure due to doxorubicin therapy. METHOD: With the use of the Hungarian financial healthcare databases merged with the National Cancer Registry, we performed a retrospective study. All the patients having confirmation for breast carcinoma between 2004 and 2015 were enrolled. The subjects with a preceding period characterized by any chemotherapy or diagnoses suggesting heart failure were excluded. Heart failure outcome event was defined by the assignment of I50 diagnosis code at hospital discharge or in autopsy reports. STATISTICAL ANALYSIS: We used multivariate binary logistic regression to calculate odds ratios for heart failure. Besides the baseline characteristics, oncological state and cumulative doses of the chemotherapies were also taken into account. RESULTS: Among the analysed 3288, doxorubicin-treated patients, heart failure cumulative incidence was 6.2%. Doxorubicin cumulative dose over 400 mg/m2 increased the risk. The heart failure incidence was essentially influenced by age, even over 50 years the risk rose. Diabetes mellitus and the treatments with pyrimidine-analogues, carboplatin or bevacizumab were also associated with higher risk. CONCLUSION: By the integration of national financial and clinical databases, we could identify the risk factors for doxorubicin-associated heart failure. Orv Hetil. 2020; 161(26): 1094-1102.

Prolonging Ticagrelor Beyond a Year of Acute Coronary Syndrome: Worth or Harmful?

Platelet activation plays a central role in triggering and complicating acute coronary syndromes, especially in case of stent thrombosis and myocardial infarction. On top of aspirin, P2Y12- inhibitors are successfully used to treat and prevent these events for a duration of one year after an acute coronary episode or 6 months after drug-eluting stent implantation. However, patients with acute coronary syndromes remain at heightened risk for recurrent ischemic events after the recommended durations of P2Y12-inhibitors and therefore, prolonging treatment is often considered in clinical practice. However, the higher risk for bleeding limits the utility of such approach to a restricted group who is still poorly defined by available measures. This review aims to discuss potential benefits and highlight important pitfalls of prolonged treatment with P2Y12-inhibitors, with a focus on ticagrelor, an attractive reversible P2Y12-inhibitor in patients after myocardial infarction.

Impact of Test Conditions on ADP-Induced Platelet Function Results With the Multiplate Assay: Is Further Standardization Required?

BACKGROUND: Platelet function testing was suggested to help tailor P2Y12-inhibitor therapy; however, the lack of proper standardization is still a limitation. METHODS: In a prospective study, we enrolled clopidogrel-treated and P2Y12-inhibitor naive patients to investigate the influence of (1) time from blood collection, (2) stability of the stored Adenosine diphosphate (ADP) reagent, and (3) the use of enoxaparin on results of the Multiplate assay. Measurements were performed from samples kept for 0, 30, 60, 120, and 240 minutes at room temperature before processing. To determine the impact of the reagent stability, freshly thawed ADP was compared with ADP kept for 3 to 5 or 8 to 13 days at 2°C to 8°C. Finally, samples containing enoxaparin at therapeutic or prophylactic doses were compared with enoxaparin-free blood. RESULTS: A total of 180 measurements were performed. ADP-stimulated platelet reactivity values decreased significantly over time (67 ± 40 U to 68 ± 37 U to 58 ± 37 U to 45 ± 33 U to 35 ± 33 U; P < .0001). Consequently, a dramatic reduction was observed in the proportion of patients with high platelet reactivity ( P < .0001). A significant drop in platelet reactivity was observed with ADP stored for 8 to 13 days as compared to freshly thawed ADP ( P = .011). Enoxaparin triggered a slight, concentration-dependent increase in platelet reactivity ( P < .05). CONCLUSION: Test conditions may have profound impacts on the obtained results with the Multiplate assay. Our findings highlight the large influence of the time from sample collection until testing, suggesting that measurements should be performed within an hour of blood collection.

[Adherence to medication after myocardial infarction and its impact on outcome: a registry-based analysis from the Hungarian Myocardial Infarction Registry]. / Szívinfarktust túlélt betegek terápiahusége a másodlagos megelozés szempontjából fontos gyógyszeres kezelésekhez.

INTRODUCTION AND AIM: The aim was to study the patients' adherence to some evidence-based medication (statins, beta blockers, platelet and RAS inhibitors) after suffering a myocardial infarction, and its impact on the outcome. METHOD: Retrospective observational cohort study was carried out from the data of the Hungarian Myocardial Infarction Registry between January 1, 2013, and December 31, 2014. 14,843 patients were alive at the end of hospital treatment, from them, those who had no myocardial infarction or death until 180 days were followed for one year. The adherence was defined as the proportion of time from the index event to the endpoint (or censoring) covered with prescription fillings. The endpoint was defined as death or reinfarction. Information on filling prescriptions for statins, platelet aggregation inhibitors, beta blockers and ARB/ACEI-inhibitors were obtained. Multivariate regression was used to model adherence and survival time. RESULTS: Good adherence (\>80%) to clopidogrel, statins, beta blockers, aspirin and ARB/ACEI was found in 64.9%, 54.4%, 36.5%, 31.7% and 64.0%, respectively. Patients treated with PCI during the index hospitalization had higher adherence to all medication (all p<0.01), except for beta-blocker (p = 0.484). Multivariate analysis confirmed that adherence to statins, to clopidogrel and ARB/ACEI-inhibitors was associated with 10.1% (p<0.0001), 10.4% (p = 0.0002) and 15.8% (p<0.0001) lower hazard of endpoint respectively for 25% points increase in adherence, controlling for age, sex, performing of PCI, 5 anamnestic data and date of index event. Adherence to aspirin and beta blockers was not significantly associated with the hazard. CONCLUSION: Higher adherence to some evidence-based medications was found to be associated with improved long term prognosis of the patients. Orv Hetil. 2017; 158(27): 1051-1057.

COOL AMI EU pilot trial: a multicentre, prospective, randomised controlled trial to assess cooling as an adjunctive therapy to percutaneous intervention in patients with acute myocardial infarction.

AIMS: We aimed to investigate the rapid induction of therapeutic hypothermia using the ZOLL Proteus Intravascular Temperature Management System in patients with anterior ST-elevation myocardial infarction (STEMI) without cardiac arrest. METHODS AND RESULTS: A total of 50 patients were randomised; 22 patients (88%; 95% confidence interval [CI]: 69-97%) in the hypothermia group and 23 patients (92%; 95% CI: 74-99) in the control group completed cardiac magnetic resonance imaging at four to six days and 30-day follow-up. Intravascular temperature at coronary guidewire crossing after 20.5 minutes of endovascular cooling decreased to 33.6°C (range 31.9-35.5°C). There was a 17-minute (95% CI: 4.6-29.8 min) cooling-related delay to reperfusion. In "per protocol" analysis, median infarct size/left ventricular mass was 16.7% in the hypothermia group versus 23.8% in the control group (absolute reduction 7.1%, relative reduction 30%; p=0.31) and median left ventricular ejection fraction (LVEF) was 42% in the hypothermia group and 40% in the control group (absolute reduction 2.4%, relative reduction 6%; p=0.36). Except for self-terminating paroxysmal atrial fibrillation (32% versus 8%; p=0.074), there was no excess of adverse events in the hypothermia group. CONCLUSIONS: We rapidly and safely cooled patients with anterior STEMI to 33.6°C at the time of coronary guidewire crossing. This is ≥1.1°C lower than in previous cooling studies. Except for self-terminating atrial fibrillation, there was no excess of adverse events and no clinically important cooling-related delay to reperfusion. A statistically non-significant numerical 7.1% absolute and 30% relative reduction in infarct size warrants a pivotal trial powered for efficacy.

[Patient care of patients with myocardial infarction in Hungary. Analysis of National Myocardial Infarction Registry data collecting in 2015]. / A szívinfarktus miatt kezelt betegek ellátása Magyarországon. A Nemzeti Szívinfarktus Regiszter 2015. évi adatainak elemzése.

The authors summarize the most relevant data of myocardial infarction patients according to the National Myocardial Infarction Registry data base. In 2015 12,681 patients had 12,941 acute myocardial infarctions. Less than half of patients (44.4%) were treated with ST elevation myocardial infarction. National Ambulance Service was the first medical contact of more than half (51.4%) of patients with ST elevation infarction. Prehospital thrombolysis was occasionally done (0.23%), but 91.6% of the patients were treated in hospital with invasive facilities. The median of the ischaemic time (time between onset of symptoms and arrival at the invasive laboratory) was 223 minutes. Most of the patients (94%) with positive coronary arteriography were treated with percutaneous coronary intervention. The 30 day mortality of the whole group was 12.8% vs. 8.6% of patients treated with an invasive procedure. CONCLUSION: comparing the national and international registry data we conclude that we should analyse and decrease the prehospital delay time to improve the patient care in Hungary. Orv. Hetil., 2017, 158(3), 90-93.

Spatial Distribution of the Cannabinoid Type 1 and Capsaicin Receptors May Contribute to the Complexity of Their Crosstalk.

The cannabinoid type 1 (CB1) receptor and the capsaicin receptor (TRPV1) exhibit co-expression and complex, but largely unknown, functional interactions in a sub-population of primary sensory neurons (PSN). We report that PSN co-expressing CB1 receptor and TRPV1 form two distinct sub-populations based on their pharmacological properties, which could be due to the distribution pattern of the two receptors. Pharmacologically, neurons respond either only to capsaicin (COR neurons) or to both capsaicin and the endogenous TRPV1 and CB1 receptor ligand anandamide (ACR neurons). Blocking or deleting the CB1 receptor only reduces both anandamide- and capsaicin-evoked responses in ACR neurons. Deleting the CB1 receptor also reduces the proportion of ACR neurons without any effect on the overall number of capsaicin-responding cells. Regarding the distribution pattern of the two receptors, neurons express CB1 and TRPV1 receptors either isolated in low densities or in close proximity with medium/high densities. We suggest that spatial distribution of the CB1 receptor and TRPV1 contributes to the complexity of their functional interaction.

Eptifibatide-induced thrombocytopenia leading to acute stent thrombosis.

A 71-year old female patient with inferior ST-elevation myocardial infarction underwent primary percutaneous coronary intervention (PCI) within 3 h of symptom onset. She was preloaded with 300 mg aspirin and 600 mg clopidogrel before PCI. Coronary angiogram showed occlusion of the right coronary artery. During PCI, eptifibatide was initiated due to the large thrombus burden. Few hours after the procedure, on eptifibatide infusion, a severe drop in platelet count was observed (from 210,000/µl to 35,000/µl) and the infusion was discontinued. One hour later, still under eptifibatide effect and with severe thrombocytopenia, acute stent thrombosis developed. Lack of prior heparin exposure, quick onset of thrombocytopenia made heparin induced thrombocytopenia improbable that was later excluded by specific immunoassay. However, platelet function testing suggested that eptifibatide induced thrombocytopenia was mediated by activating autoantibodies since platelet reactivity was paradoxically very high at the time of stent thrombosis but decreased radically with eptifibatide washout. The patient was successfully managed without further complications on the basis of platelet function data obtained in the subsequent days. This rare subtype of thrombocytopenia highlights that not only platelet count but also platelet function should be closely monitored in case of severe thrombocytopenia to better balance bleeding and thrombosis.

Is flourishing good for the heart? Relationships between positive psychol characteristics and cardiorespiratory health / ¿Es la salud psicológica buena para el corazón? Relación entre características psicológicas positivas y variables cardiorrespiratorias

The purpose of this study was to provide further data on the relationships between positive psychology constructs and cardiorespiratory parameters including arterial stiffness indicators. Hypotheses were tested cross-sectionally on a sample of patients with cardiovascular disease and on a healthy sample. Life satisfaction, psychological well-being, optimism, meaning in life, and sense of coherence were included as psychological indicators, while peripheral and central blood pressure, arterial stiffness, and heart cycle and respiratory function parameters were used as physiological variables. Most of the associations examined were not significant in either sample, with some notable exceptions (the direction of these linear relationships was in accordance with our expectations). Satisfaction with life was related to lower peripheral systolic and mean arterial blood pressure in the clinical sample. Further, sense of coherence was positively associated with forced expiratory volume. In the healthy sample, the augmentation indexes and aortic systolic blood pressure were negatively associated with optimism. However, none of the linear and non-linear relationships proved to be significant in either of the samples when using the Bonferroni correction. Further research should determine whether the present findings derive from the cultural characteristics of our samples or whether the mediators between flourishing and cardiorespiratory health should be sought among other variables than the ones included in the present investigation

Introducción: Muchos estudios han demostrado que las características psicológicas positivas son factores de protección contra las enfermedades cardiovasculares. El objetivo de este estudio es ampliar los datos conocidos acerca de las relaciones entre las cualidades positivas y los parámetros cardiorrespiratorios, incluida la rigidez arterial. Método: Las hipótesis fueron contrastadas transversalmente en una muestra clínica de pacientes con enfermedades cardiovasculares y otra muestra de pacientes sanos. La satisfacción en la vida, el bienestar psicológico, el optimismo, el sentido de la vida y el sentimiento de coherencia fueron considerados indicadores psicológicos, mientras que las variables fisiológicas tenidas en cuenta fueron la presión arterial periférica y central, la rigidez arterial, el ciclo cardiaco y la función respiratoria. La relación entre las variables dependientes e independientes, ajustadas por sexo, edad y nivel educativo se analizó mediante un modelo lineal. También se examinaron las relaciones no lineales entre las variables dependientes e independientes. Resultados: La mayoría de las asociaciones estudiadas no fueron significativas para ninguna de las dos muestras, aunque con algunas excepciones notables: la satisfacción en la vida se relacionó con una tensión arterial sistólica periférica menor, así como con una presión arterial media más baja en la muestra clínica. El sentido de la coherencia se asoció positivamente al volumen respiratorio forzado. En la muestra sana, el índice aórtico y la presión arterial sistólica presentaron una asociación negativa con el optimismo; sin embargo, utilizando la corrección de Bonferroni, ninguna de las relaciones lineales o no lineales resultaron significativas en las muestras. Conclusiones: estudios futuros deberán determinar si estos hallazgos derivan de las características culturales de estas muestras en concreto, o si los mediadores entre la salud psicológica y la salud cardiorrespiratoria deberían ser buscados más allá de las variables incluidas en este estudio

Optimizing P2Y12 receptor inhibition in patients with acute coronary syndrome on the basis of platelet function testing: impact of prasugrel and high-dose clopidogrel.

OBJECTIVES: This study sought to evaluate the impact of treatment with prasugrel and high-dose clopidogrel on the basis of platelet function testing in patients with acute coronary syndrome (ACS) who are undergoing percutaneous coronary intervention (PCI). BACKGROUND: The clinical impact of treatment with prasugrel in patients with ACS who have high platelet reactivity (HPR) is unknown. METHODS: Patients with ACS who were pre-treated with clopidogrel and undergoing successful PCI were enrolled in a single-center, prospective registry. Platelet function was measured 12 to 36 h after PCI with the Multiplate device (Roche Diagnostics GmbH, Mannheim, Germany). Patients with HPR (>46 U) were switched to prasugrel or treated with high-dose clopidogrel, and those without HPR continued treatment with 75 mg of clopidogrel. RESULTS: A total of 741 consecutive patients were enrolled in the study between September 2011 and August 2012, and 219 of these patients (29.5%) had HPR. Although platelet reactivity decreased after treatment adjustments in those with HPR, prasugrel provided significantly more potent platelet inhibition compared with high-dose clopidogrel (p < 0.0001). Compared with patients without HPR, the risk of all-cause death, myocardial infarction, stent thrombosis, or stroke at 1 year was significantly higher in the high-dose clopidogrel group (hazard ratio [HR]: 2.27; 95% confidence interval [CI]: 1.45 to 3.55; p < 0.0001), and patients who were switched to prasugrel had similar outcomes (HR: 0.90; 95% CI: 0.44 to 1.81; p = 0.76). Bleeding Academic Research Consortium (BARC) type 3/5 bleeding was also more frequent in patients treated with high-dose clopidogrel (HR: 2.09; 95% CI: 1.05 to 4.17; p = 0.04) than in patients switched to prasugrel (HR: 0.45; 95% CI: 0.11 to 1.91; p = 0.28). In a multivariate model, HPR with high-dose clopidogrel, but not with prasugrel, was an independent predictor of the composite ischemic endpoint (HR: 1.90; 95% CI: 1.17 to 3.08; p = 0.01). CONCLUSIONS: Switching patients with ACS who have HPR to treatment with prasugrel reduces thrombotic and bleeding events to a level similar to that of those without HPR; however, there is a higher risk of both thrombotic and bleeding complications with high-dose clopidogrel.

Characterisation of cannabinoid 1 receptor expression in the perikarya, and peripheral and spinal processes of primary sensory neurons.

The cannabinoid 1 (CB1) receptor is expressed by a sub-population of primary sensory neurons. However, data on the neurochemical identity of the CB1 receptor-expressing cells, and CB1 receptor expression by the peripheral and central terminals of these neurons are inconsistent and limited. We characterised CB1 receptor expression in dorsal root ganglia (DRG) and spinal cord at the lumbar 4-5 level, as well as in the urinary bladder and glabrous skin of the hindpaw. About 1/3 of DRG neurons exhibited immunopositivity for the CB1 receptor, the majority of which showed positivity for the nociceptive markers calcitonin gene-related peptide (CGRP) or/and Griffonia (bandeiraea) simplicifolia IB4 isolectin-binding. Virtually all CB1 receptor-immunostained fibres showed immunopositivity for CGRP in the skin, while very few did in the urinary bladder. No CB1 receptor-immunopositive nerve fibres were IB4 positive in either peripheral tissue. Spinal laminae I and II-outer showed the highest density of CB1 receptor-immunopositive punctae, the majority of which showed positivity for CGRP or/and IB4 binding. These data indicate that a major sub-population of nociceptive primary sensory neurons expresses CB1 receptors that are transported to both peripheral and central terminals of these cells. Therefore, the present data suggest that manipulation of endogenous CB1 receptor agonist levels in these areas may significantly reduce nociceptive input into the spinal cord.

Successful sealing of a coronary artery perforation with a mesh-covered stent.

Coronary artery perforation is a rare, but particularly feared and sometimes life-threatening, complication of percutaneous coronary interventions. The incidence of coronary perforation has increased with newer, more invasive interventional devices and techniques like rotablation, excimer laser coronary angioplasty, routine high-pressure balloon dilatation, or chronic total occlusion interventions. Here we describe a case of Ellis grade 2 perforation following a balloon dilatation performed in an in-stent restenotic total occlusion. The perforation was successfully sealed with a recently introduced device, a mesh covered stent (MGuard stent, Inspire MD). This new stent is much more flexible than the polytetrafluoroethylene-covered stent, which is often implanted in Ellis 2 or 3 grade perforations.

Severe burn injury induces a characteristic activation of extracellular signal-regulated kinase 1/2 in spinal dorsal horn neurons.

We have studied scalding-type burn injury-induced activation of extracellular signal-regulated kinase 1/2 (ERK1/2) in the spinal dorsal horn, which is a recognised marker for spinal nociceptive processing. At 5min after severe scalding injury to mouse hind-paw, a substantial number of phosphorylated ERK1/2 (pERK1/2) immunopositive neurons were found in the ipsilateral dorsal horn. At 1h post-injury, the number of pERK1/2-labelled neurons remained substantially the same. However, at 3h post-injury, a further increase in the number of labelled neurons was found on the ipsilateral side, while a remarkable increase in the number of labelled neurons on the contralateral side resulted in there being no significant difference between the extent of the labelling on both sides. By 6h post-injury, the number of labelled neurons was reduced on both sides without there being significant difference between the two sides. A similar pattern of severe scalding injury-induced activation of ERK1/2 in spinal dorsal horn neurons over the same time-course was found in mice which lacked the transient receptor potential type 1 receptor (TRPV1) except that the extent to which ERK1/2 was activated in the ipsilateral dorsal horn at 5 min post-injury was significantly greater in wild-type animals when compared to TRPV1 null animals. This difference in activation of ERK1/2 in spinal dorsal horn neurons was abolished within 1h after injury, demonstrating that TRPV1 is not essential for the maintenance of ongoing spinal nociceptive processing in inflammatory pain conditions in mouse resulting from at least certain types of severe burn injury.

Structure and stereochemistry of novel ecdysteroids from the roots of Serratula wolffii.

Three new natural ecdysteroids viz. 22-dehydro-20-deoxy-ajugasterone C (1), 1-hydroxy-22-deoxy-20,21-didehydro-ecdysone (2) and 22-deoxy-20,21-didehydro-ecdysone (3) were isolated from the methanol extract of the roots of Serratula wolffii. The structures of compounds 1-3 were established by various spectroscopic techniques, including one- and two-dimensional NMR, circular dichroism and mass spectroscopic methods.

Crossing dendrites of the hypoglossal motoneurons: possible morphological substrate of coordinated and synchronized tongue movements of the frog, Rana esculenta.

Application of different fluorescent tracers to the right and left hypoglossal nerve of the frog revealed the extent of dendrites crossing the midline into the territory of contralateral hypoglossal motoneurons. By using confocal microscopy, a large number of close appositions were detected between hypoglossal motoneurons bilaterally, which formed dendrodendritic and dendrosomatic contacts. The distance between the neighboring profiles suggested close membrane appositions without interposing glial elements. Application of neurobiotin to one hypoglossal nerve resulted in labeling of perikarya exclusively on the ipsilateral side of tracer application, suggesting the absence of dye-coupled connections with contralateral hypoglossal motoneurons. At the ultrastructural level, the dendrodendritic and dendrosomatic contacts did not show any morphological specialization; the long membrane appositions may provide electrotonic interactions between the neighboring profiles. We propose that dendrites of hypoglossal motoneurons that cross the midline subserve one of the morphological substrates of co-activation, synchronization and timing of bilateral activity of tongue muscles during prey-catching behavior of the frog.

Modification of innervation pattern by fluoroquinolone treatment in the rat salivary glands.

Fluoroquinolone antibiotics (FQAs) are widely used in dental and medical therapy. Despite their known severe adverse actions on the central and peripheral nervous system, little attention has been directed toward the potential toxic side effects of these compounds on the oral tissues. As the saliva secretion is controlled by the nervous system and neuropeptides, the neurotoxic effect of pefloxacin (PEF), a representative member of FQAs, was studied in rats in the present work. Previously, we demonstrated a significant weight loss of parotid gland tissue, a marked decrease in 3H-thymidine incorporation, a decreased volume of saliva and amylase activity of the glandular tissue in response to PEF. Animals received intraperitoneal injection of PEF (20 mg/100 g body weight daily) for 3 and 7 days. Normal histology, and neurofilament 200, substance P (SP) and calcitonin gene-related polypeptide (CGRP) containing nerve fibers were detected with immunohistochemical methods. A marked decrease of the weights in salivary glands and the acinar diameters were measured. Similarly, a strong and significant decrease of the number of SP and CGRP containing nerve fibers were detected. These findings suggest that the impaired morphology and innervation pattern of salivary glands is related to the neurotoxic adverse effect of FQA treatment.

Gradient HPLC separation of dehydroepiandrosterone (DHEA) from its metabolites and biological congeners: role of tetrahydrofuran in the chromatographic mechanism.

A three-step gradient reversed-phase high-performance liquid chromatography (RP-HPLC) method was developed for the separation of dehydroepiandrosterone (DHEA), its sulfate ester (DHEA-S), its three C7-oxidized metabolites (7alphaOH-DHEA, 7betaOH-DHEA, 7-keto-DHEA), and its biosynthetic congeners (androstenedione, testosterone, estradiol, pregnenolone). This new method allows the quantitative characterization of DHEA metabolism and biosynthetic transformation under given physiological, pathological, or therapeutically influenced circumstances. Tetrahydrofuran probably acts as a proton acceptor coadsorbent, while isopropanol behaves as a proton donor during the separation of testosterone, estradiol, and the stereoisomers of 7-OH-DHEA.

Vestibular afferents to the motoneurons of glossopharyngeal and vagus nerves in the frog, Rana esculenta.

The aim of this work was to study whether the vestibular afferent fibers establish direct connections with the motoneurons of glossopharyngeal and vagus nerves of the frog, Rana esculenta. In anaesthetized animals the vestibulocochlear nerve and the common root of glossopharyngeal-vagus and accessory (IX-X-XI) nerves were simultaneously labeled with fluorescein dextran amine (vestibulocochlear nerve) and tetramethylrhodamine dextran amine (IX-X-XI). With a confocal laser scanning microscope we could detect close appositions between the vestibular afferent fibers and somatodendritic components of the general and special visceral motoneurons of the ambiguus nucleus of IX-X nerves. The direct impulse transmission may provide a quick and immediate response of cardiovascular and gastrointestinal system upon body displacement.