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1.
Angew Chem Int Ed Engl ; : e202408321, 2024 Jun 26.
Article de Anglais | MEDLINE | ID: mdl-38926096

RÉSUMÉ

exo-6b2-Methyl-substituted pentabenzocorannulene (exoPBC-Me) was synthesized by the palladium-catalyzed cyclization of 1,2,3-triaryl-1H-cyclopenta[l]phenanthrene. Its bowl-shaped geometry with an sp3 carbon atom in the backbone and a methyl group located at the convex (exo) face was verified by X-ray crystallography. According to DFT calculations, the observed conformer is energetically more favorable than the endo one by 39.9 kcal/mol. Compared to the nitrogen-doped analogs with intact π-conjugated backbones (see the main text), exo-PBC-Me displayed a deeper bowl depth (avg. 1.93 Å), redshifted and broader absorption (250-620 nm) and emission (from 585 to more than 850 nm) bands and a smaller optical HOMO-LUMO gap (2.01 eV). exo-PBC-Me formed polar crystals where all bowl-in-bowl stacking with close π···π contacts is arranged unidirectionally, providing the potential for applications as organic semiconductors and pyroelectric materials. This unusual structural feature, molecular packing, and properties are most likely associated with the assistance of the methyl group and the sp3 carbon atom in the backbone.

2.
J Radiol Prot ; 44(1)2024 Jan 19.
Article de Anglais | MEDLINE | ID: mdl-38194908

RÉSUMÉ

Cancer is a major health challenge and causes millions of deaths worldwide each year, and the incidence of lung cancer has increased. Augmented fluoroscopic bronchoscopy (AFB) procedures, which combine bronchoscopy and fluoroscopy, are crucial for diagnosing and treating lung cancer. However, fluoroscopy exposes patients and physicians to radiation, and therefore, the procedure requires careful monitoring. The National Council on Radiation Protection and Measurement and the International Commission on Radiological Protection have emphasised the importance of monitoring patient doses and ensuring occupational radiation safety. The present study evaluated radiation doses during AFB procedures, focusing on patient skin doses, the effective dose, and the personal dose equivalent to the eye lens for physicians. Skin doses were measured using thermoluminescent dosimeters. Peak skin doses were observed on the sides of the patients' arms, particularly on the side closest to the x-ray tube. Differences in the procedures and experience of physicians between the two hospitals involved in this study were investigated. AFB procedures were conducted more efficiently at Hospital A than at Hospital B, resulting in lower effective doses. Cone-beam computed tomography (CT) contributes significantly to patient effective doses because it has higher radiographic parameters. Despite their higher radiographic parameters, AFB procedures resulted in smaller skin doses than did image-guided interventional and CT fluoroscopy procedures. The effective doses differed between the two hospitals of this study due to workflow differences, with cone-beam CT playing a dominant role. No significant differences in left and right eyeHp(3) values were observed between the hospitals. For both hospitals, theHp(3) values were below the recommended limits, indicating that radiation monitoring may not be required for AFB procedures. This study provides insights into radiation exposure during AFB procedures, concerning radiation dosimetry, and safety for patients and physicians.


Sujet(s)
Tumeurs du poumon , Exposition professionnelle , Médecins , Exposition aux rayonnements , Humains , Bronchoscopie , Radioscopie , Dose de rayonnement , Tumeurs du poumon/imagerie diagnostique , Exposition professionnelle/prévention et contrôle , Exposition professionnelle/analyse
3.
Article de Anglais | MEDLINE | ID: mdl-32454860

RÉSUMÉ

OBJECTIVE: To evaluate the effectiveness and safety of acupuncture treatment for dysphagia as a complication of stroke. Methods and Design. This is a multicenter, pragmatic, nonrandomized, self-controlled clinical trial. A total of 39 patients were recruited from several Chinese medicine outpatient clinics and hospital-affiliated speech therapy outpatient clinics in Hong Kong. 26 patients completed all the 24 sessions of acupuncture treatment within two months, and only 12 of them were used as self-control. For the self-control group, the retrospective clinical data was taken from the electronic patient records with patient consent. The descriptive swallowing function data were converted into the quantitative Royal Brisbane Hospital Outcome Measure for Swallowing (RBHOMS) scores by two registered speech therapists through a validation process. And the data were validated by reaching consensus between the two speech therapists. All subjects underwent a baseline assessment before commencement of treatment, and outcome assessments were conducted upon the completion of treatment. The primary outcome measure is the RBHOMS score, which is a swallowing disability rating scale for monitoring difficulties in daily swallowing function. Secondary outcome measures include the Chinese version of the Swallow Quality-of-Life Questionnaire and adverse events. All the primary and secondary outcomes were assessed at baseline as well as at the end of acupuncture treatment (month 2). RESULTS: A total of 39 participants aged 46 to 89 years were enrolled in the study, and the male-to-female ratio was 15 : 11. The mean baseline RBHOMS score of all 39 participants was 5.92 ± 2.23. The mean retrospective RBHOMS score of the 12 subjects who were used as self-control was 5.67 ± 1.72 before enrollment, while the mean RBHOMS score of the 26 participants who completed all the 24 sessions of treatment was 6.92 ± 2.07. There were statistically significant differences between the RBHOMS score at the completion of treatment and baseline (p=0.006), and retrospective data (p=0.042). Moreover, a significant difference was also found in terms of swallow quality-of-life score before and after acupuncture treatment (p < 0.01). CONCLUSIONS: This pilot study provides preliminary evidence for the effectiveness of acupuncture for poststroke dysphagia. The findings from this trial can be used as a foundation for future full-scale randomized controlled clinical trials to assess the efficacy and safety of acupuncture for poststroke dysphagia. Ethics and Dissemination. The ethical approval of the clinical research study was granted by the Research Ethics Committee of both New Territories East and West Cluster of Hong Kong. Written informed consent was obtained from all participants, and the study was undertaken according to the ICH-GCP Guidelines. Trial Registration. This trial is registered with ChiCTR-TRC-12002621 and the registration date is 2012-10-26.

4.
Sheng Li Xue Bao ; 71(6): 809-823, 2019 Dec 25.
Article de Anglais | MEDLINE | ID: mdl-31879736

RÉSUMÉ

Spinal α-motoneurons directly innervate skeletal muscles and function as the final common path for movement and behavior. The processes that determine the excitability of motoneurons are critical for the execution of motor behavior. In fact, it has been noted that spinal motoneurons receive various neuromodulatory inputs, especially monoaminergic one. However, the roles of histamine and hypothalamic histaminergic innervation on spinal motoneurons and the underlying ionic mechanisms are still largely unknown. In the present study, by using the method of intracellular recording on rat spinal slices, we found that activation of either H1 or H2 receptor potentiated repetitive firing behavior and increased the excitability of spinal α-motoneurons. Both of blockage of K+ channels and activation of Na+-Ca2+ exchangers were involved in the H1 receptor-mediated excitation on spinal motoneurons, whereas the hyperpolarization-activated cyclic nucleotide-gated (HCN) channels were responsible for the H2 receptor-mediated excitation. The results suggest that, through switching functional status of ion channels and exchangers coupled to histamine receptors, histamine effectively biases the excitability of the spinal α-motoneurons. In this way, the hypothalamospinal histaminergic innervation may directly modulate final motor outputs and actively regulate spinal motor reflexes and motor execution.


Sujet(s)
Histamine , Motoneurones , Animaux , Histamine/pharmacologie , Canaux contrôlés par les nucléotides cycliques et activés par l'hyperpolarisation/métabolisme , Motoneurones/effets des médicaments et des substances chimiques , Motoneurones/physiologie , Rats , Récepteur histaminergique H2/métabolisme , Échangeur sodium-calcium/métabolisme
5.
Int J Mol Sci ; 19(4)2018 Mar 22.
Article de Anglais | MEDLINE | ID: mdl-29565268

RÉSUMÉ

Hinokitiol, a natural monoterpenoid from the heartwood of Calocedrus formosana, has been reported to have anticancer effects against various cancer cell lines. However, the detailed molecular mechanisms and the inhibiting roles of hinokitiol on adenocarcinoma A549 cells remain to be fully elucidated. Thus, the current study was designed to evaluate the effect of hinokitiol on the migration of human lung adenocarcinoma A549 cells in vitro. The data demonstrates that hinokitiol does not effectively inhibit the viability of A549 cells at up to a 10 µM concentration. When treated with non-toxic doses (1-5 µM) of hinokitiol, the cell migration is markedly suppressed at 5 µM. Hinokitiol significantly reduced p53 expression, followed by attenuation of Bax in A549 cells. A dose-dependent inhibition of activated caspase-9 and -3 was observed in the presence of hinokitiol. An observed increase in protein expression of matrix metalloproteinases (MMPs) -2/-9 in A549 cells was significantly inhibited by hinokitiol. Remarkably, when A549 cells were subjected to hinokitiol (1-5 µM), there was an increase in the activities of antioxidant enzymes catalase (CAT) and superoxide dismutase (SOD) from the reduction in cells. In addition, the incubation of A549 cells with hinokitiol significantly activated the cytochrome c expression, which may be triggered by activation of caspase-9 followed by caspase-3. These observations indicate that hinokitiol inhibited the migration of lung cancer A549 cells through several mechanisms, including the activation of caspases-9 and -3, induction of p53/Bax and antioxidant CAT and SOD, and reduction of MMP-2 and -9 activities. It also induces cytochrome c expression. These findings demonstrate a new therapeutic potential for hinokitiol in lung cancer chemoprevention.


Sujet(s)
Matrix metalloproteinases/métabolisme , Monoterpènes/pharmacologie , Tropolone/analogues et dérivés , Cellules A549 , Apoptose/effets des médicaments et des substances chimiques , Caspase-3/métabolisme , Caspase-9/métabolisme , Catalase/métabolisme , Mouvement cellulaire/effets des médicaments et des substances chimiques , Prolifération cellulaire/effets des médicaments et des substances chimiques , Cytochromes c/métabolisme , Humains , Matrix metalloproteinase 2/métabolisme , Superoxide dismutase/métabolisme , Tropolone/pharmacologie
6.
Article de Anglais | MEDLINE | ID: mdl-28003848

RÉSUMÉ

This was a prospective multicenter observational study, aiming to explore the effects of acupuncture on smoking cessation in Hong Kong. From March of 2010 to August of 2015, a total of 5202 smokers were recruited based on inclusion criteria and treated with acupuncture for 8 weeks. As a result, 2940 subjects finished the study with a drop-out rate of 43.48%. The self-reported 7-day point abstinence rate was 34.00% in Week 8 and 18.40% in Week 52. The exhaled carbon monoxide level and the number of cigarettes smoked per day were reduced significantly after treatment. The time to relapse was calculated to be 38.71 days. In addition, "cigarettes smoked per day," "Fagerstrom Test for Nicotine Dependence," "total sessions of acupuncture," "whether finished 8 acupuncture treatments in the first month," and "total sessions of acupuncture" were believed to be essential factors for abstinence success. It was concluded that acupuncture was a safe method for smoking cessation and was effective in helping smokers to quit; therefore, acupuncture could be considered as one of the methods to help smokers quit. Further studies regarding the effect differences between acupuncture and medications were needed to clarify the overall benefits of acupuncture.

7.
Sci Rep ; 6: 25657, 2016 05 10.
Article de Anglais | MEDLINE | ID: mdl-27160770

RÉSUMÉ

Osthole, an active coumarin isolated from Cnidium monnieri (L.) Cusson, has long been used in China as an antipruritic herbal medicine; however, the antipruitic mechanism of osthole is unknown. We studied the molecular mechanism of osthole in histamine-dependent itch by behavioral test, Ca(2+) imaging, and electrophysiological experiments. First, osthole clearly remitted the scratching behaviors of mice induced with histamine, HTMT, and VUF8430. Second, in cultured dorsal root ganglion (DRG) neurons, osthole showed a dose-dependent inhibitory effect to histamine. On the same neurons, osthole also decreased the response to capsaicin and histamine. In further tests, the capsaicin-induced inward currents were inhibited by osthole. These results revealed that osthole inhibited histamine-dependent itch by modulating TRPV1 activity. This study will be helpful in understanding how osthole exerts anti-pruritus effects and suggests that osthole may be a useful treatment medicine for histamine-dependent itch.


Sujet(s)
Coumarines/pharmacologie , Ouverture et fermeture des portes des canaux ioniques/effets des médicaments et des substances chimiques , Prurit/prévention et contrôle , Canaux cationiques TRPV/métabolisme , Animaux , Antiprurigineux/pharmacologie , Calcium/métabolisme , Inhibiteurs des canaux calciques/pharmacologie , Capsaïcine/pharmacologie , Cellules cultivées , Ganglions sensitifs des nerfs spinaux/cytologie , Histamine , Mâle , Souris de lignée C57BL , Neurones/effets des médicaments et des substances chimiques , Neurones/métabolisme , Prurit/induit chimiquement , Prurit/métabolisme
8.
Mol Neurobiol ; 53(2): 1386-1401, 2016 Mar.
Article de Anglais | MEDLINE | ID: mdl-25633097

RÉSUMÉ

Insights into function of central histaminergic system, a general modulator originating from the hypothalamus for whole brain activity, in motor control are critical for understanding the mechanism underlying somatic-nonsomatic integration. Here, we show a novel selective role of histamine in the cerebellar nuclei, the final integrative center and output of the cerebellum. Histamine depolarizes projection neurons but not interneurons in the cerebellar nuclei via the hyperpolarization-activated cyclic nucleotide-gated (HCN) channels coupled to histamine H2 receptors, which are exclusively expressed on glutamatergic and glycinergic projection neurons. Furthermore, blockage of HCN channels to block endogenous histaminergic afferent inputs in the cerebellar nuclei significantly attenuates motor balance and coordination. Therefore, through directly and quickly modulation on projection neurons but not interneurons in the cerebellar nuclei, central histaminergic system may act as a critical biasing force to not only promptly regulate ongoing movement but also realize a rapid integration of somatic and nonsomatic response.


Sujet(s)
Cervelet/cytologie , Canaux cationiques contrôlés par les nucléotides cycliques/métabolisme , Histamine/pharmacologie , Activité motrice/effets des médicaments et des substances chimiques , Neurones/métabolisme , Animaux , Femelle , Acide glutamique/métabolisme , Interneurones/métabolisme , Mâle , Potentiels de membrane/effets des médicaments et des substances chimiques , Neurones/effets des médicaments et des substances chimiques , Rat Sprague-Dawley , Récepteur histaminergique H2/métabolisme
9.
Article de Anglais | MEDLINE | ID: mdl-26347786

RÉSUMÉ

Background. Observational studies of smoking cessation with acupuncture have been reported widely; however, few researchers have focused on its predictors. Objective. This paper attempts to explore the predictors for smoking cessation with acupuncture in a Hong Kong population, aiming to provide references for clinical treatment in the future. Methods. We performed a secondary analysis of data from our observational study "Acupuncture for Smoking Cessation (2011-2014)" in Hong Kong. A total of 23 indexes were selected as possible predictors, and study participants with complete information of 23 indexes were included. By taking 8-week and 52-week smoking cessation results as dependent variables, binary logistic regression method was used to identify the predictors. Additionally, based on an M5P decision-tree algorithm, an equation of "successful rate of smoking cessation with acupuncture" was calculated. Results. (1) 2,051 study participants were included in total. (2) According to the results of binary logistic regression, variables including treatment location, total number of acupuncture sessions received, and whether the study participants received at least 6 sessions of acupuncture were taken as the short-term predictors; gender, treatment location, Fagerstrom Test for Nicotine Dependence (FTND), and total number of acupuncture sessions received were taken as the long-term predictors. (3) According to study participants' FTND, treatment location, and number of cigarettes smoked/day, the equation of "successful rate of smoking cessation with acupuncture" was established. Conclusion. Receiving sufficient and qualified acupuncture is the leading factor for short-term smoking cessation with acupuncture, whereas individual factors and smoking background play a more important role in long-term smoking cessation with acupuncture.

10.
Neurosignals ; 21(3-4): 174-83, 2013.
Article de Anglais | MEDLINE | ID: mdl-23006827

RÉSUMÉ

The superior vestibular nucleus (SVN), which holds a key position in vestibulo-ocular reflexes and nystagmus, receives direct hypothalamic histaminergic innervations. By using rat brainstem slice preparations and extracellular unitary recordings, we investigated the effect of histamine on SVN neurons and the underlying receptor mechanisms. Bath application of histamine evoked an excitatory response of the SVN neurons, which was not blocked by the low-Ca(2+)/high-Mg(2+) medium, indicating a direct postsynaptic effect of the amine. Selective histamine H1 receptor agonist 2-pyridylethylamine and H2 receptor agonist dimaprit, rather than VUF8430, a selective H4 receptor agonist, mimicked the excitation of histamine on SVN neurons. In addition, selective H1 receptor antagonist mepyramine and H2 receptor antagonist ranitidine, but not JNJ7777120, a selective H4 receptor antagonist, partially blocked the excitatory response of SVN neurons to histamine. Moreover, mepyramine together with ranitidine nearly totally blocked the histamine-induced excitation. Immunostainings further showed that histamine H1 and H2 instead of H4 receptors existed in the SVN. These results demonstrate that histamine excites the SVN neurons via postsynaptic histamine H1 and H2 receptors, and suggest that the central histaminergic innervation from the hypothalamus may actively bias the SVN neuronal activity and subsequently modulate the SVN-mediated vestibular functions and gaze control.


Sujet(s)
Potentiels d'action/effets des médicaments et des substances chimiques , Histamine/pharmacologie , Neurones/effets des médicaments et des substances chimiques , Récepteur histaminergique H1/métabolisme , Récepteur histaminergique H2/métabolisme , Noyaux vestibulaires/effets des médicaments et des substances chimiques , Animaux , Dimaprit/pharmacologie , Femelle , Agonistes histaminergiques/pharmacologie , Mâle , Neurones/métabolisme , Pyridines/pharmacologie , Rats , Rat Sprague-Dawley , Noyaux vestibulaires/métabolisme
11.
J Neurosci Res ; 90(1): 132-42, 2012 Jan.
Article de Anglais | MEDLINE | ID: mdl-21922515

RÉSUMÉ

The central histaminergic nervous system, originating from the tuberomammillary nucleus of the hypothalamus, widely innervates almost the whole brain as well as the spinal cord. However, the effect of histamine on spinal motoneurons, the final common path for motor control, is still unknown. By using 8-14-day-old rat spinal slice preparations and intracellular recordings, the effect of histamine on motoneurons in lumbar spinal cord and the underlying mechanisms were studied. Bath application of histamine (30-300 µM) induced a membrane depolarization in the majority of recorded spinal motoneurons (78/90, 86%). Perfusing slices with tetrodotoxin or low-Ca(2+) /high-Mg(2+) medium did not block the histamine-induced excitation, indicating a direct postsynaptic action of histamine on motoneurons. Separate application of the selective histamine H(1) receptor antagonist mepyramine or the selective histamine H(2) receptor antagonist ranitidine partially suppressed the histamine-induced excitation, whereas a combination of ranitidine and mepyramine totally blocked the excitatory effect of histamine on motoneurons. On the other hand, both the selective histamine H(1) receptor agonist 2-pyridylethylamine and the selective histamine H(2) receptor agonist dimaprit mimicked the excitation of histamine on spinal motoneurons. These agonist-induced excitations were also blocked by mepyramine or ranitidine. Furthermore, histamine affected membrane input resistance and potentiated repetitive firing behavior of spinal motoneurons. These results demonstrate that histamine excites rat spinal motoneurons via the histamine H(1) and H(2) receptors and increases their excitability, suggesting that the hypothalamospinal histaminergic fibers may directly modulate final motor outputs and actively regulate ongoing motor execution andspinal motor reflexes.


Sujet(s)
Histamine/pharmacologie , Motoneurones/effets des médicaments et des substances chimiques , Récepteur histaminergique H1/métabolisme , Récepteur histaminergique H2/métabolisme , Moelle spinale/cytologie , Potentiels d'action/effets des médicaments et des substances chimiques , Analyse de variance , Animaux , Animaux nouveau-nés , Biophysique , Inhibiteurs des canaux calciques/pharmacologie , Dimaprit/pharmacologie , Relation dose-effet des médicaments , Stimulation électrique , Agonistes histaminergiques/pharmacologie , Antihistaminiques des récepteurs H2/pharmacologie , Techniques in vitro , Techniques de patch-clamp , Pyridines/pharmacologie , Ranitidine/pharmacologie , Rats , Tétrodotoxine/pharmacologie
12.
Behav Brain Res ; 228(1): 44-52, 2012 Mar 01.
Article de Anglais | MEDLINE | ID: mdl-22146592

RÉSUMÉ

The cerebellar fastigial nucleus (FN), together with the interpositus nucleus (IN), constitutes the two final output nuclei of the spinocerebellum and plays an important role in body and limb movements. Previous studies have revealed a direct histaminergic projection from the hypothalamus to the cerebellar nuclei and an excitatory effect of histamine on the IN neurons. However, role of hypothalamic histaminergic projection in the FN has been still little known. Here we show that histamine elicited the FN neurons of rats a concentration-dependent excitatory response in vitro. The histamine-induced excitation on FN neurons was mediated by postsynaptic histamine H2 rather than H1 receptors. In behavioral tests, microinjection of histamine into bilateral FNs remarkably improved motor performances of rats on both accelerating rota-rod and balance beam. Selective H2 receptor antagonist ranitidine considerably declined those motor performances and selective H2 receptor agonist dimaprit mimicked the facilitation effect of histamine on the movements. But selective H1 receptor antagonist triprolidine and agonist 2-pyridylethylamine had no effect. Furthermore, microinjection of histamine into bilateral FNs narrowed stride width of footprint but did not influence wire suspension, whereas microinjection of histamine into bilateral INs increased stride length and promoted suspension. These results demonstrate that histamine enhances rat motor balance and coordination through modulation of both proximal and distal muscles by activation of histamine H2 receptors in the cerebellar FN and IN, and suggest that the hypothalamocerebellar histaminergic projections may modulate the final outputs of the spinocerebellum and participate in the cerebellum-mediated motor control.


Sujet(s)
Noyaux du cervelet/physiologie , Agents histaminiques/pharmacologie , Histamine/pharmacologie , Histamine/physiologie , Activité motrice/physiologie , Récepteur histaminergique H2/physiologie , Potentiels d'action/effets des médicaments et des substances chimiques , Potentiels d'action/physiologie , Animaux , Noyaux du cervelet/effets des médicaments et des substances chimiques , Relation dose-effet des médicaments , Interactions médicamenteuses , Histamine/administration et posologie , Agonistes histaminergiques/administration et posologie , Agonistes histaminergiques/pharmacologie , Antihistaminiques des récepteurs H1/administration et posologie , Antihistaminiques des récepteurs H1/pharmacologie , Antihistaminiques des récepteurs H2/administration et posologie , Antihistaminiques des récepteurs H2/pharmacologie , Mâle , Microinjections , Activité motrice/effets des médicaments et des substances chimiques , Rats , Récepteur histaminergique H1/effets des médicaments et des substances chimiques , Récepteur histaminergique H1/physiologie , Récepteur histaminergique H2/effets des médicaments et des substances chimiques
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