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1.
2.

Background

Rosacea is a chronic inflammatory skin condition whose etiology has been linked to mast cells and the antimicrobial peptide cathelicidin LL-37. Individuals with refractory disease have demonstrated clinical benefit with periodic injections of onabotulinum toxin, but the mechanism of action is unknown.

Objectives

To investigate the molecular mechanism by which botulinum toxin improves rosacea lesions.

Methods

Primary human and murine mast cells were pretreated with onabotulinum toxin A or B or control. Mast cell degranulation was evaluated by β-hexosaminidase activity. Expression of botulinum toxin receptor Sv2 was measured by qPCR. The presence of SNAP-25 and VAMP2 was established by immunofluorescence. In vivo rosacea model was established by intradermally injecting LL-37 with or without onabotulinum toxin A pretreatment. Mast cell degranulation was assessed in vivo by histologic counts. Rosacea biomarkers were analyzed by qPCR of mouse skin sections.

Results

Onabotulinum toxin A and B inhibited compound 48/80-induced degranulation of both human and murine mast cells. Expression of Sv2 was established in mouse mast cells. Onabotulinum toxin A and B increased cleaved SNAP-25 and decreased VAMP2 staining in mast cells respectively. In mice, injection of onabotulinum toxin A significantly reduced LL-37-induced skin erythema, mast cell degranulation, and mRNA expression of rosacea biomarkers.

Conclusions

These findings suggest that onabotulinum toxin reduces rosacea-associated skin inflammation by directly inhibiting mast cell degranulation. Periodic applications of onabotulinum toxin may be an effective therapy for refractory rosacea and deserves further study.  相似文献   
3.
AIM: The aim of the present study was to investigate the influence of endogenous estradiol and estrogen and estrogen-progestin therapies on concentration in pre- and postmenopausal women. MATERIALS AND METHODS: The study groups consisted of 26 women with surgical menopause (mean+/-standard deviation (SD): age 51.8+/-2.6 years, body mass index (BMI) 26.45+/-4.56 kg/m(2)), 54 with natural menopause (mean+/-SD: age 50.5+/-3.0 years, BMI 25.75+/-4.09 kg/m(2)) and 40 premenopausal controls (mean+/-SD: age 48.3+/-2.3 years, BMI 26.23+/-4.12 kg/m(2)). The group with surgical menopause received estradiol transdermally (50 microg/day) and those with natural menopause received additionally medroxyprogesterone acetate (5 mg/day) for the last 12 days of the cycle. Before and after 4 months of therapy, body weight, waist and hip circumferences and blood pressure were measured, and BMI and waist-to-hip ratio (WHR) were calculated. Serum leptin, follicle-stimulating hormone (FSH), estradiol (E(2)), testosterone, prolactin and dehydroepiandrosterone sulfate (DHEAS) were measured prior to and after treatment. RESULTS: Leptin concentrations did not differ statistically among the groups. No correlations between leptin and E(2), FSH, prolactin, testosterone and DHEAS concentrations were found in any of the groups before and after treatment. Leptin level correlated positively with body mass, BMI and hip and waist circumferences in all groups. There were no correlations between leptin and WHR in the pre- and postmenopausal groups. In the premenopausal group and in some postmenopausal groups, serum leptin level correlated with blood pressure. CONCLUSIONS: Endogenous E(2) and androgens in premenopausal women and estrogen and estrogen-progestin therapies in postmenopausal subjects do not influence serum leptin concentrations. Leptin level is related to body mass and BMI, but not to sex hormone status. The distribution of adipose tissue and the type of obesity (android or gynoid) have no influence on serum leptin concentration. The correlation between serum leptin level and blood pressure requires further investigation.  相似文献   
4.
. Neutrophil-mediated tissue damage has been implicated in the pathogenesis of diarrhoea-associated haemolytic uraemic syndrome (D+ HUS). This study evaluates priming and activation of the neutrophil oxidative burst in D+ HUS using chemiluminescent techniques. Peripheral blood neutrophils from 11 children with acute D+ HUS were examined. No difference was found in the oxidative burst of neutrophils from patients and controls. Serum elastase levels were measured in 8 patients and found to be significantly elevated. Although elastase results suggest neutrophil activation, chemiluminescence studies do not confirm this in the peripheral blood neutrophil. This does not support a significant role for circulating agents in priming and activating the peripheral blood neutrophil. Received August 17, 1995; received in revised form and accepted November 27, 1995  相似文献   
5.
Twenty-eight members of the general public, with little nutritional knowledge and no previous commitment to dietary change, completed 7-day-weighed dietary diaries. They then attempted to change their diets, where appropriate, in line with current nutritional guidelines.
The panel achieved changes in diet that were consistent with the recent recommendations but several problems arose. In particular, although fat levels were reduced, energy levels fell and fibre goals were not reached; in addition, certain of the initial vitamin and mineral intakes gave cause for concern. These results emphasize the importance of giving advice not only about foods that might be reduced in the diet, but also about food that might be used as alternatives. They also illustrate the difficulty of persuading people to make radical changes to their eating habits even when given personal advice from a nutritionist.
The panel was small and not necessarily representative, but the results illustrate the need for more dietary analysis studies. It is not enough simply to formulate appropriate guidelines from a nutritional point of view; it is also important to ensure that the public understands them and that people make sensible decisions about their diet.  相似文献   
6.
Summary A patient who developed a unilateral opercular syndrome following a cerebrovascular accident is described. Computed tomography showed that the lesion did not affect the opercular cortex, but involved deep white matter and the head of the caudate nucleus of the left hemisphere. Persistent hypophonia and transient aphasia were associated. Comparison with previous cases is discussed.  相似文献   
7.
During May 1986, a survey to assess the frequency of allergic disorders was conducted among primary school children of Alghero, Sardinia, using a structured self-administered questionnaire. The following problems were investigated: allergic conjunctivitis, asthma, wheezing, allergic rhinitis, urticaria and eczema. Of the original 1823 questionnaires distributed, 1961 (92.8%) were completed by parents and returned. Overall, 238 children (14.1%) were reported to have shown at least one episode of one or more of the above and were regarded as 'allergic'. Among the potential risk factors investigated, statistically significant differences (P less than 0.05) between allergic and non-allergic children were only found for history of allergy in at least one parent (odds ratio, OR = 2.2) and exposure to passive smoking (OR = 1.4).  相似文献   
8.
The effect of thyrotrophin-releasing hormone (TRH) on intracellular free Ca2+ concentration, [Ca2+)i, was investigated with the fluorescent dye fura-2 in cell suspensions obtained from 13 human growth hormone-secreting adenomas and 6 adrenocorticotrophin-secreting adenomas. Preoperatively, 9 out of 13 acromegalic patients showed a positive growth hormone response to TRH administration while none of the 6 patients with Cushing's disease had a plasma adrenocorticotrophin increase after TRH injection. In all the growth hormone-secreting adenomas the addition of TRH (100 nM) caused a significant rise in [Ca2+]i (from a resting level of 133±40 (±SD) to a value of 284±119 nM at 100 nM TRH, n = 42; P<0.001). The transient induced by TRH was found to have a dual origin, one due to Ca2+ mobilization from intracellular stores which was maintained in presence of EGTA (3mM) and verapamil (10 μM) and a plateau phase due to Ca2+ influx from the extracellular media. Somatostatin (0.1 μM) lowered both resting [Ca2+]i and TRH-induced transients. The effect of gonadotrophin-releasing hormone on [Ca2+]i was evaluated on cell suspensions obtained from 6 growth hormone-secreting adenomas. Gonadotrophin-releasing hormone (100 nM) caused a marked rise in [Ca2+]i (from 179±25 to 283±15nM) on the cell suspension obtained from the only in vivo responsive adenoma while it was ineffective in the remaining 5. Although TRH was ineffective in modifying plasma adrenocorticotrophin levels in all patients with Cushing's disease, in 5 out of 6 tumors the addition of 100 nM TRH caused a significant rise in [Ca2+]i (from 102.5 ± 36 to 163±66 nM, n = 22; P < 0.005). However, the effect of TRH on [Ca2+]i was significantly lower than that caused by arginine vasopressin, a physiological stimulator of adrenocorticotrophin release ([Ca2+]i values; 145±78 nM at 100 nM TRH versus 300±140 at 10 nM arginine vasopressin, n = 15; P<0.05). Moreover, the effect of arginine vasopressin on [Ca2+]i was detectable at concentrations as low as 0.1 nM while TRH was effective at concentrations higher than 1 nM. By contrast, gonadotrophin-releasing hormone was ineffective in increasing [Ca2]i in all the adrenocorticotrophin-secreting adenomas studied. Collectively, these data indicate that sensitivity to TRH is present in almost all the growth hormone- and adrenocorticotrophin-secreting adenomas independently of the responsiveness of the individual patients to the peptide.  相似文献   
9.
10.
Electrical stimulation of the phrenic nerve afferents evoked excitatory responses in the right inferior cardiac sympathetic nerve in chloralose-anaesthetized cats. The reflex was recorded in intact and spinal cats. The latency and threshold of the volley recorded from the phrenic nerve as well as of the cord dorsum potentials evoked by electrical stimulation of the phrenic nerve indicated that group III afferents were responsible for this reflex. The phrenicocardiac sympathetic reflex recorded in intact cats was followed by a silent period. The maximum amplitude of the reflex discharges was 800 microV, the latency was 83 ms and the central transmission time 53 ms. Duration of the silent period lasted up to 0.83 s. In spinal cats the reflex was recorded 5.5-8 h after spinalization. The maximum amplitude of the spinal reflex discharges ranged from 22 to 91 microV and the latency from 36 to 66 ms.  相似文献   
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