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81.
Vittorio Scaravilli Silvia Scansani Alice Grasso Amedeo Guzzardella Marco Vicenzi Irene Rota Mario Nosotti Alberto Zanella Francesco Blasi Antonio Pesenti Giacomo Grasselli 《Transplantation proceedings》2021,53(1):260-264
Knowledge of preoperative right heart function of adult patients with cystic fibrosis (CF) awaiting lung transplant (LUTX) is limited. The echocardiography of adult patients with CF enlisted for LUTX was retrospectively analyzed and compared with standards and invasive analyses (right heart catheterization, multigated radionuclide ventriculography). We included 49 patients (reported as mean ± standard deviation; 29 ± 9 years of age; forced expiratory volume in first second of expiration, 31% ± 11% predicted; lung allocation score, 36 ± 5; invasive mean pulmonary artery pressure, 17 ± 5 mm Hg; multigated radionuclide ventriculography right ventricle [RV] ejection fraction, 50% ± 9%). Patients had increased RV end-diastolic area, RV wall thickness, and increased pulmonary artery acceleration time with subnormal tricuspid annular plane systolic excursion, tissue Doppler positive peak systolic velocity, and fraction area change. Subnormal tricuspid annular plane systolic excursion (< 23 mm), tissue Doppler positive peak systolic velocity (< 14 cm/s), and fraction area change (< 49%) had high sensitivity and negative predictive value in predicting impaired RV.ejection fractionA good correlation between echocardiographic estimated and invasively measured systolic pulmonary artery pressure was observed (R2 = 0.554, P < .001). Adults with CF awaiting LUTX have morphologic alterations of the right heart, with subclinical impairment of RV systolic function. Echocardiography may be used as a bedside, repeatable, and reliable noninvasive test to screen further deterioration in RV function while on the waiting list for LUTX. More prospective follow-up echocardiographic studies are necessary to confirm such a hypothesis. 相似文献
82.
Tammy Ju MD Deshka Foster MD PhD Ashley Titan MD Saleh Najjar MD Gregory R. Bean MD PhD Kristen Ganjoo MD Irene Wapnir MD 《The breast journal》2021,27(9):723-725
Radiation-induced breast angiosarcoma, or secondary angiosarcoma (SAS), is a rare entity with a high risk of metastatic recurrence. Herein, we describe the use of intraoperative fluorescence-based skin angiography to guide surgical resection following a novel immunotherapy-based regimen for SAS resulting in a complete pathological response. 相似文献
83.
Grasl-Kraupp Bettina; Huber Wolfgang; Timmermann-Trosiener Irene; Schulte-Hermann Rolf 《Carcinogenesis》1993,14(11):2435-2437
Putative preneoplastic foci of spontaneous origin could be detectedin the livers of 2 year old, untreated male Wistar rats. Theunaltered and preneoplastic hepatocytes showed an identicalexpression of the peroxisomal marker enzyme acyl-CoA oxidase,as determined by immunohistochemical staining. A single doseof the peroxisome proliferator (PP) nafenopin (NAF) inducedthe enzyme predominantly in hepatocytes around the central venulesand cell replication mainly in the periportal areas. However,upon one NAF application almost all of the preneoplastic focishowed a considerably weaker immunoreaction for peroxisomalacyl-CoA oxidase than the surrounding tissue. ConcomitantlyNAF elevated replicative DNA synthesis index in foci up to 相似文献
84.
An antimutagenic compound was isolated from the leaves of Carmonaretusa (Vahl) Masam. Its structure has been elucidated by spectralanalysis to be 4-hydroxy-7,8,11,12,15,7',8',ll',12',15'-decahydro-ß,-carotene. The results of the Micronucleus Test, an in vivomethod, showed that the isolated antimutagenic compound reducedby 68.4% the number of micronucleated polychromatic erythrocytesinduced by tetracycline, a known mutagen. 相似文献
85.
Purpose To review the pathogenesis, clinical presentation, diagnostic assessment and treatment regimens of steroid-induced bone loss. Data sources An English-language literature search (MEDLINE 1966-1999) and bibliographic reviews of textbooks and review articles. Study selection Cross-sectional and prospective studies with BMD measurements or fracture rate. Results The greatest rate of bone loss occur during the first 6 to 12 months of steroid therapy, affecting trabecular more than cortical bone. High steroid dosage for a prolonged period, prevalent fracture, hypogonadism, older age, low calcium intake and family history of osteoporosis are risk factors for steroid-induced bone loss. Based on bone density results, patients with osteoporosis or osteopenia with a T-score below -1.5 should receive antiresorptive treatment during steroid therapy. Among the various antiresorptive agents, bisphosphonates have the strongest evidence of preventing steroid-induced bone loss. Conclusion The most important step in the management of steroid-induced osteoporosis is the proper assessment of the individual patient’s risk of bone loss, and the selection of appropriate anti-resorptive agent for each patient. 相似文献
86.
Pacini Laura Limatola Cristina De Laurenzi Vincenzo Ricci Irene Spinedi Angelo 《Journal of neuro-oncology》1997,31(1-2):141-146
In the human neuroblastoma cell line SK-N-BE(2), arachidonic acid (AA), supplied in the medium at micromolar concentrations, markedly ehnanced [14C]stearic acid (SA) (but not [14C]palmitic acid or [14C]oleic acid) incorporation into phosphatidylinositol (PtdIns). AA failed to stimulate [14C]SA incorporation into PtdIns precursors, namely phosphatidic acid and cytidinediphosphodiacylglycerol; furthermore, enhanced [14C]SA incorporation, brought about by exogenously administered AA, was not restricted to PtdIns tetraenoic species. When cells were pulsed for 1 h with [14C]SA (either in the presence or absence of AA) and then reincubated in AA- and [14C]SA-free medium, a marked loss of radioactivity from PtdIns was observed, that however was restricted to molecular species other than tetraenoic. These results are discussed in the light of possible mechanisms through which PtdIns achieves the 1-stearoyl-2-arachidonoyl configuration. 相似文献
87.
Anna Siniscalchi Irene Badini Clementina Bianchi Lorenzo Beani 《Naunyn-Schmiedeberg's archives of pharmacology》1994,350(1):10-14
The influence exerted by monoamines on acetylcholine release was studied in electrically stimulated slices of guinea pig nucleus basalis magnocellularis (nbM) prelabelled with 3H-choline (3H-Ch).Noradrenaline, 30 M, and clonidine, 1 M, reduced the evoked 3H-Ch efflux by about 50%, but phenylephrine, 100 M. did not; idazoxan, 0.1 M. but not prazosin, 1 M, antagonized these effects. pointing to the involvement of alpha2 receptors. Apomorphine, 1 or 30 M. reduced 3H-Ch efflux from nbM slices as well. The effect was shared by quinpirole, 1 or 10 M, but not by 2,3,4,5-tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-benz-azepine (SKF 38393). 10 M, and was antagonized by sulpiride, 1 M, but not by R-(+)-8-chloro-2,3,4,5-tetra-hydro-3-methyl-5-phenyl-1H-3-benzazepin-7-ol (SCH 23390). 1 M, suggesting the involvement of the D2 receptor subtype.5-hydroxytryptamine (5-HT) 0.3–30 M, and alphamethyl-5-HT, 10 M, significantly increased 3H-Ch efflux from nbM slices; the 5-HT2 antagonist ritanserin, 1 M. prevented this response. 2-methyl-5-HT, 1–30 M, inhibited the evoked 3H-Ch efflux and its effect was prevented by the 5-HT3 antagonist 1H,3,5H-tropan-3-yl-3,5-dichlorobenzoate (MDL 72222). 1 M.These findings indicate that i) catecholamines inhibit nbM neurons through alpha2 and D2 receptors and that ii) a complex serotonergic modulation of cholinergic function exists in the nbM, involving the activation of various receptor subtypes. which can mediate opposite responses.
Correspondence to: A. Siniscalchi at the above address 相似文献
88.
Yolanda S. López-Boado Irene Díez-Itza Jorge Tolivia Carlos López-Otín 《Breast cancer research and treatment》1994,29(3):247-258
Summary We have studied the hormonal regulation of the gene encoding Zn-2-glycoprotein (Zn-2-gp), a human protein with a high degree of amino acid sequence similarity to class I histocompatibility antigens that is produced by a specific subset of breast carcinomas. Northern blot analysis revealed that dexamethasone and 5-dihydrotestosterone strongly induced the accumulation of Zn-2-gp mRNA in T-47D human breast cancer cells. Furthermore, the effect of these two hormones was shown to be additive, since the combination of both hormones produced a stimulation of Zn-2-gp mRNA of at least 3-fold over that produced by either hormone alone. By contrast, the addition of 5-dihydrotestosterone, 17-estradiol, or progesterone failed to induce the expression of Zn-2-gp. The stimulatory effect of glucocorticoids and androgens on Zn-2-gp expression was produced in a time and dose dependent manner, without significantly affecting the cell proliferation rate. A time-course study demonstrated that the induction of Zn-2-gp mRNA by androgens and glucocorticoids reached a level of 4 or 3.2-fold over the untreated control after seven days of incubation in the presence of a 10–7 M concentration of 5-dihydrotestosterone or dexamethasone, respectively. A dose-response study showed that as little as 10–11 M of 5-dihydrotestosterone or dexamethasone produced an accumulation of Zn-2-gp mRNA of 2.4 or 2.1-fold over the control, respectively. On the basis of these results, we propose that Zn-2-gp may be useful as a biochemical marker of breast carcinomas with a specific pattern of hormone responsiveness in whose development glucocorticoids and/or androgens may play a significant role. 相似文献
89.
Ramn Alvarenga Ariadna Gonzlez del Angel Victoria del Castillo Silvestre García de la Puente Irene Mauln Alessandra Carnevale 《American journal of medical genetics. Part A》1995,56(2):173-175
Several patients with the Silver-Russell syndrome (SRS) attending our Genetics Clinic were diagnosed as having persistent metabolic acidosis. Since this abnormality has not been reported previously in the SRS, we reexamined 33 SRS patients to evaluate the frequency and type of metabolic acidosis, the clinical and laboratory findings, and the growth pattern in SRS patients with and without metabolic acidosis. Among them, 14 had a consistent decrease in HCO levels. Renal studies in acidotic patients showed urine pH of 5.8 and 24 h urine calcium of <2.4 mg/kg/24 h; serum creatinine, excretion of glucose, and aminoacids were normal, as were renal ultrasound and excretory urography findings. These data supported the diagnosis of renal tubular acidosis, probably type II; the patients were treated with oral bicarbonate and acidosis was corrected successfully. Clinical manifestations were similar in acidotic and non-acidotic patients. The nutritional indices at diagnosis and at last evaluation (at least 8 months after diagnosis) were abnormally low in all patients; however, acidotic patients, treated with bicarbonate, showed an improvement of nutritional status particularly in the weight/height index, although the difference between groups after follow-up did not reach statistical significance. We suggest that metabolic acidosis due to renal tubular acidosis, probably type II, may occur in children with the SRS and should be looked for and treated in all patients. © 1995 Wiley-Liss, Inc. 相似文献
90.
Pilot study of a visitor volunteer programme for community elderly people receiving home health care
MacIntyre I Corradetti P Roberts J Browne G Watt S Lane A 《Health & social care in the community》1999,7(3):225-232
There is a need to evaluate community support programmes for elderly people. In this randomized control trial (RCT), we determined the effectiveness of 'friendly visitors' in a volunteer programme of a visiting nurses organization in Southern Ontario, Canada. The Volunteer Friendly Visitor Programme was developed to support elderly people receiving homemaking and nursing care in the community. Volunteers are screened, trained, interviewed and matched to homebound elderly clients for general interest, visit expectations and personality. Volunteers spend three to four hours on average per week with clients socializing in mutually agreed-upon ways. The nursing staff identified clients who were lonely for this additional support. These newly-referred clients were randomly allocated to receive a friendly visitor or not for six weeks. Those receiving the volunteer visitor improved in life satisfaction and two social support measures: worth and social integration. Thus, the addition of volunteer visitors to planned homemaking and nursing care made a difference for elderly in the community. 相似文献