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MEMRI and tumors: a method for the evaluation of the contribution of Mn(II) ions in the extracellular compartment
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Eliana Gianolio Francesca Arena Enza Di Gregorio Roberto Pagliarin Martina Delbianco Gabriella Baio Silvio Aime 《NMR in biomedicine》2015,28(9):1104-1110
The purpose of the work was to set‐up a simple method to evaluate the contribution of Mn2+ ions in the intra‐ and extracellular tumor compartments in a MEMRI experiment. This task has been tackled by “silencing” the relaxation enhancement arising from Mn2+ ions in the extracellular space. In vitro relaxometric measurements allowed assessment of the sequestering activity of DO2A (1,4,7,10‐tetraazacyclododecane‐1,7‐diacetic acid) towards Mn2+ ions, as the addition of Ca‐DO2A to a solution of MnCl2 causes a drop of relaxivity upon the formation of the highly stable and low‐relaxivity Mn‐DO2A. It has been proved that the sequestering ability of DO2A towards Mn2+ ions is also fully effective in the presence of serum albumin. Moreover, it has been shown that Mn‐DO2A does not enter cell membranes, nor does the presence of Ca‐DO2A in the extracellular space prompt migration of Mn ions from the intracellular compartment. On this basis the in vivo, instantaneous, drop in SE% (percent signal enhancement) in T1‐weighted images is taken as evidence of the sequestration of extracellular Mn2+ ions upon addition of Ca‐DO2A. By applying the method to B16F10 tumor bearing mice, T1 decrease is readily detected in the tumor region, whereas a negligible change in SE% is observed in kidneys, liver and muscle. The relaxometric MRI results have been validated by ICP‐MS measurements. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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Béla Nagy Zsolt Bene Zsolt Fejes Sonya L. Heltshe David Reid Nicola J. Ronan Yvonne McCarthy Daniel Smith Attila Nagy Elizabeth Joseloff György Balla János Kappelmayer Milan Macek Scott C. Bell Barry J. Plant Margarida D. Amaral István Balogh 《Journal of cystic fibrosis》2019,18(2):271-277
Background
We have recently shown that human epididymis protein 4 (HE4) levels correlate with the severity of cystic fibrosis (CF) lung disease. However, there are no data on how HE4 levels alter in patients receiving CFTR modulating therapy.Methods
In this retrospective clinical study, 3 independent CF patient cohorts (US-American: 29, Australian: 12 and Irish: 19 cases) were enrolled carrying at least one Class III CFTR CF-causing mutation (p.Gly551Asp) and being treated with CFTR potentiator ivacaftor. Plasma HE4 was measured by immunoassay before treatment (baseline) and 1–6?months after commencement of ivacaftor, and were correlated with FEV1 (% predicted), sweat chloride, C-reactive protein (CRP) and body mass index (BMI).Results
After 1?month of therapy, HE4 levels were significantly lower than at baseline and remained decreased up to 6?months. A significant inverse correlation between absolute and delta values of HE4 and FEV1 (r?=??0.5376; P?<?.001 and r?=??0.3285; P?<?.001), was retrospectively observed in pooled groups, including an independent association of HE4 with FEV1 by multiple regression analysis (β?=??0.57, P?=?.019). Substantial area under the receiver operating characteristic curve (ROC-AUC) value was determined for HE4 when 7% mean change of FEV1 (0.722 [95% CI 0.581–0.863]; P?=?.029) were used as classifier, especially in the first 2?months of treatment (0.806 [95% CI 0.665–0.947]; P?<?.001).Conclusions
This study shows that plasma HE4 levels inversely correlate with lung function improvement in CF patients receiving ivacaftor. Overall, this potential biomarker may be of value for routine clinical and laboratory follow-up of CFTR modulating therapy. 相似文献5.
The differences between the postprandial mixing or propulsion and the interdigestive motility of the gastrointestinal (GI)
tract are already known. Earlier studies showed dose-dependent differences in the effects of erythromycin on interdigestive
motility. The various GI side-effects (vomiting, diarrhoea) also suggest that there are different effects of erythromycin
on the GI motility. The aim of our study was to examine postprandially the propulsive effects of different doses of erythromycin
on the movement of intraluminal contents in the upper GI tract of the rat. The animals were fasted for 24 h before the experiments
but water was given freely. The rats received 1.5 ml 1.5% methylcellulose painted with 0.05% phenol-red intragastrically (test
solution). Erythromycin(E. lactobionate) was given intravenously at doses of 0.05, 0.1, 0.25, 0.5, 1.0 and 5.0 mg/kg 15 min before the administration of a test solution.
The animals were sacrificed 20,60 and 120 min after administration of methylcellulose, when the distance between the front
of the painted intraluminal contents and the pylorus was measured and expressed as a percentage of the total length of small
intestine. The phenol-red content in the stomach and small intestine was measured spectrophotometrically and the gastric emptying
was calculated from the ratio of the measured total and intestinal phenol-red content. Our results showed that the small doses
of erythromycin (0.1 and 0.25 mg/kg) accelerated gastric emptying after 20 min but did not change significantly the propulsive
motility of upper small intestine; however, large doses of erythromycin (1.0 and 5.0 mg/kg) decreased gastric emptying and
upper GI motility after 20 and 60 min. In summary, the prokinetic action of small doses of erythromycin was demonstrated,
but its effecttime on GI motility is short and the ratio of the stimulating and inhibitory doses is 1:10.
This paper was presented at the Section of IUPHAR GI Pharmacology Symposium on ’Biochemical pharmacology as an approach to
gastrointestinal disorders (basic science to clinical perspectives)‘, October 12-14, 1995, Pécs, Hungary. 相似文献
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Lucio Lucchin Amleto D’Amicis Maria Gabriella Gentile Nino Carlo Battistini Maria Antonia Fusco Augusta Palmo Maurizio Muscaritoli Franco Contaldo Emanuele Cereda 《Mediterranean journal of nutrition and metabolism》2009,2(3):171-179
Aim and methods Nutrition, unhealthy lifestyles and cancer appear to be strictly related, but few authors have analysed the interest in dietary
information of cancer patients and their families. This survey was conducted in the Veneto area (Italy) to investigate the
concern of cancer patients and their family members about diet as a health tool before and after diagnosis of cancer.
Results Seven hundred and four questionnaires were collected: 380 from cancer patients and 324 from family members of cancer subjects.
Breast cancer (BC) was the most frequent disease for patients (61.8%) as well as families (26.5%). Generally, the importance
of having precise diet information after diagnosis is recognised by 40.3% of patients, with significant differences between
the various types of cancer: gastric and colon/rectum cancer (GCC) patients were more concerned than BC women about precise
information concerning a diet to follow immediately after diagnosis (p = 0.000, ODs = 3.10, CI 1.68–5.71) or during treatments (p = 0.001, ODs = 2.67, CI 1.46–4.89). The nutritional information is supplied to patients in 34% of cases and to relatives
in 30.3%, often from non-medical sources. In total healthcare workers (family doctor, oncologist, surgeon, dietician) represented
the exclusive source of dietary information for 24.9% of patients and 22.9% of family members. Diet after diagnosis changes
in 69.1% of GCC patients and in 39.2% of BC women. Relatives, particularly women, report difficulties preparing patients’
meals in 30.7% of cases, changes in the eating habits of the entire family in 29.9% and discontent connected with patients
diet in 13.9%. The concern about proper nutrition after diagnosis increases more in GCC subjects (p < 0.025) when compared to BC subjects and in patients with more recent diagnosis (p < 0.041) when compared with patients with diagnosis >5 years ago, while in family members the interest in diet after diagnosis
increases more in women than in men (p < 0.030) without other differences regarding the degree of relationship, type of cancer or diagnosis time. Relatives (92.7%)
have more interest in nutritional education than patients (74.9%). Cancer patients <65 years were more interested in educational
initiatives concerning nutrition (p = 0.000, ODs = 4.46, CI 2.6–7.4) than older patients (>65 years) and female subjects were more concerned than male patients
(p = 0.008, ODs = 2.11, CI 1.2–3.6).
Conclusions The interest in the dietary knowledge and in educational initiatives concerning nutrition is high in cancer patients and their
relatives, although it decreases with the age. The poor attention paid to nutrition of cancer patients by various healthcare
workers deserves consideration, since the psychophysical wellbeing and perhaps also survival of cancer patients can be improved
by correct dietary management, as well as, naturally, by the principal treatments themselves. 相似文献
8.
Levente Gáspár Zoltán Jónás László Kiss György Vereb Zoltán Csernátony 《European journal of orthopaedic surgery & traumatology : orthopedie traumatologie》2009,19(6):403-407
Background Coccygodynia can cause severe pain and disability in patients. There are contradictions in the literature regarding the final
results of coccygectomy for coccygodynia. We evaluated the long-term effects of coccygectomy on the intensity, characteristics,
and manifestation of pain caused by coccygodynia to determine the adequacy of operation among treatment modalities.
Materials and methods Thirty-four patients with coccygodynia were treated by coccygectomy. In 22 cases, trauma, and in one case childbirth was the
cause. 11 cases were regarded as idiopathic. The intensity, characteristics of pain, and the most painful activities were
evaluated at an average of 7.6 (3–18) years of follow-up time.
Results Before the operation, all 34 patients had pain while sitting, moreover, 26 of them had pain during standing, walking, at night
or a combination of these. 21 patients had intolerable or very intensive, mainly acute, sharp or burning pain. 11 patients
had dyschesia, 2 had dysuria and 6 had dyspareunia. At follow-up, 7 patients were completely free of pain, 15 others had moderate,
11 medium, and only one patient had severe, but none had intolerable pain. Only seven patients had acute, sharp or burning
pain postoperatively. The decrease of average pain score from 8.0 to 3.2 was significant (P < 10−12). The number of the patients with dyschesia and dyspareunia decreased from 11 to 7 and from 6 to 3, respectively. Two patients
had dysuria, but their complaints did not change after the operation. One of the two patients who needed reoperation had an
excellent final result, while the other remained unchanged. 12 and 16 patients (together 82%) regarded the final result of
the operation excellent and good, respectively. The condition of five others did not change, while one became worse. The patients
with younger age, smaller body mass index, and less co-morbidities had better final result. There were no serious complications.
Conclusion Coccygectomy for coccygodynia is a safe method to decrease the intensity of pain and other complaints of the patients. The
operation can be the choice of treatment if conservative measures fail. 相似文献
9.
The impact of continuous positive airway pressure (CPAP) treatment on the airway responsiveness of asthmatic subjects with obstructive sleep apnoea (OSA) has scarcely been studied. A prospective study was performed comparing the changes in airway responsiveness and quality of life in stable asthmatic OSA patients, before and 6 weeks after their nocturnal CPAP treatment. A total of 20 subjects (11 males and nine females) participated in the study. With the nocturnal CPAP treatment, the apnoea/hypopnoea index dropped from 48.1 +/- 23.6 x h(-1) to 2.6 +/- 2.5 x h(-1). There were no significant changes in airway responsiveness after CPAP treatment (provocative concentration causing a 20% fall in forced expiratory volume in one second (FEV(1); PC(20) 2.5 mg x mL(-1) (1.4-4.5)) compared with baseline (PC(20) 2.2 mg x mL(-1) (1.3-3.5)). There was no significant change in FEV(1) either. However, the asthma quality of life of the subjects improved from 5.0 +/- 1.2 at baseline to 5.8 +/- 0.9 at the end of the study. In conclusion, nocturnal continuous positive airway pressure treatment did not alter airway responsiveness or forced expiratory volume in one second in subjects with stable mild-to-moderate asthma and newly diagnosed obstructive sleep apnoea. However, nocturnal continuous positive airway pressure treatment did improve asthma quality of life. 相似文献
10.
Leandro Provinciali Mario Signorino Bruno Censori Gabriella Ceravolo Maria Del Pesce 《Epilepsia》1991,32(5):684-689
The occurrence of transitory cognitive impairment during diffuse subclinical electroencephalographic (EEG) discharges has been widely documented but the role of the parameters influencing the cognitive performance and the involvement of motor or verbal response in the tasks used is still under debate. Fifteen patients suffering from primary generalized epilepsy with frequent bisynchronous EEG epileptic bursts underwent a shape recognition task during EEG monitoring. The test sequence was as follows: memorandum, pause, and multiple choice set. After pressing the response button, the patient was asked to confirm the choice verbally. The following parameters were considered: geometrical complexity of the shape, chronological position of the burst occurring during the single test, and the duration of discharge ranging from 1 to 3 s. Results showed a significant increase in incorrect responses during the test when discharges occurred, with more errors occurring for difficult than for easy shapes. Neither the discharge position nor the duration of the epileptic burst influenced the performance. Diffuse epileptic activity of short duration produced selective effects on the cognitive process regardless of the motor component of the response. 相似文献