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41.
42.
Objective: Emerging evidence suggests that specific sub-populations of cancer cells with stem cell characteristics within the bulk of tumours are implicated in the pathogenesis of heterogeneous malignant tumours. The cells that drive tumour growth have been denoted cancer-initiating cells or cancer stem cells (hereafter CSCs). CSCs have been isolated initially from leukaemias and subsequently from several solid tumours including brain, breast, prostate, colon and lung cancer. This study aimed at isolating and characterising the population of tumour-initiating cells in non-small-cell lung cancer (NSCLC). Methods: Specimens of NSCLC obtained from 89 patients undergoing tumour resection at the Cancer National Institute of Naples were analysed. Three methods to isolate the tumour-initiating cells were used: (1) flow cytometry analysis for identification of positive cells for surface markers such as CD24, CD29, CD31, CD34, CD44, CD133 and CD326; (2) Hoechst 33342 dye exclusion test for the identification of a side-population characteristic for the presence of stem cells; (3) non-adherent culture condition able to form spheres with stem cell-like characteristics. Definition of the tumourigenic potential of the cells through soft agar assay and injection into NOD/SCID mice were used to functionally define (in vitro and in vivo) putative CSCs isolated from NSCLC samples. Results: Upon flow cytometry analysis of NSCLC samples, CD133-positive cells were found in 72% of 89 fresh specimens analysed and, on average, represented 6% of the total cells. Moreover, the number of CD133-positive cells increased markedly when the cells, isolated from NSCLC specimens, were grown as spheres in non-adherent culture conditions. Cells from NSCLC, grown as spheres, when assayed in soft agar, give rise to a 3.8-fold larger number of colonies in culture and are more tumourigenic in non-obese diabetic (NOD)/severe combined immunodeficiency (SCID) mice compared with the corresponding adherent cells. Conclusions: We have isolated and characterised a population of CD133-positive cells from NSCLC that is able to give rise to spheres and can act as tumour-initiating cells.  相似文献   
43.
Vitamin D receptor (VDR) gene polymorphisms could be considered one of the factors influencing the efficacy of the anti-osteoporotic treatments. In this multicenter, prospective, randomized and controlled trial we evaluated whether BsmI vitamin D receptor (VDR) genotypes influence the efficacy of antiresorptive treatment regimes (administered alone or in combination) in postmenopausal osteoporotic women. Using restriction endonuclease, we identified the BsmI VDR polymorphism in 1,100 postmenopausal women with osteoporosis. The women were randomized, taking account of genotype, into five treatment groups: (1) alendronate (Aln, 10 mg/day) plus raloxifene (Rlx, 60 mg/day); (2) Aln plus hormone replacement therapy (HRT, 0.625 mg/day conjugated equine estrogens plus 2.5 mg/day medroxyprogesterone acetate); (3) Aln alone; (4) HRT alone; and (5) Rlx alone. Lumbar-spine bone mineral density (BMD) and bone turnover markers were measured at study entry and after 1 year of treatment. Using the general linear model (GLM) repeated-measures procedure, the means of BMD and bone turnover markers significantly differed from baseline after a period of treatment. In particular, the mean change from baseline for BMD was –0.034 (95% confidence interval [CI]: –0.037 to –0.031, P <0.001); for serum osteocalcin (OC) it was 1.369 (95% CI: 1.289 to 1.448, P <0.001); and for urinary deoxypyridinoline (DPD) it was 1.322 (95% CI: 1.242 to 1.401, P <0.001), indicating a considerable variation before and after treatment of these indicators. In all three cases these effects appeared significantly influenced by treatments, genotypes, and the treatments*genotypes interaction term (P <0.001 each, except for the BMD and genotype effect with P =0.02), and not by the investigational centers involved in the study. In conclusion, in postmenopausal osteoporotic women, BsmI VDR genotypes influence the efficacy of antiresorptive drugs particularly when used in combination.  相似文献   
44.
Transplant pneumonectomy is a rarely performed procedure. It is occasionally carried out in the course of retransplantation. To our knowledge, resection of a transplanted lung without its replacement and with successful outcome in the adult has not been previously reported. We present a case of elective left transplant pneumonectomy in a 38-year-old man 6 years after left single-lung transplant. At 12 months after resection, the patient remains well, with good exercise tolerance.  相似文献   
45.
There is increasing proof that organ preservation by machine perfusion is able to limit ischemia/reperfusion injury in kidney transplantation. This study was designed to compare the efficiency in hypothermic organ preservation by machine perfusion or cold storage in an animal model of kidney autotransplantation.
Twelve pigs underwent left nephrectomy after warm ischemic time; the organs were preserved in machine perfusion ( n  = 6) or cold storage ( n  = 6) and then autotransplanted with immediate contralateral nephrectomy. The following parameters were compared between the two groups of animals: hematological and urine indexes of renal function, blood/gas analysis values, histological features, tissue adenosine-5'-triphosphate (ATP) content, perforin gene expression in kidney biopsies, and organ weight changes were compared before and after preservation.
The amount of cellular ATP was significantly higher in organs preserved by machine perfusion; moreover, the study of apoptosis induction revealed an enhanced perforin expression in the kidneys, which underwent simple hypothermic preservation compared to the machine-preserved ones. Organ weight was significantly decreased after cold storage, but it remained quite stable for machine-perfused kidneys.
The present model seems to suggest that organ preservation by hypothermic machine perfusion is able to better control cellular impairment in comparison with cold storage.  相似文献   
46.

Purpose

This study was undertaken to evaluate the feasibility, safety and efficacy of a new combined single-step therapy in patients with unresectable multinodular unilobar hepatocellular carcinoma (HCC), with at least one lesion >3 cm, with balloon-occluded radiofrequency ablation (BO-RFA) plus transcatheter arterial chemoembolization (TACE) of the main lesion and TACE of the other lesions. The second purpose of our study was to compare the initial effects in terms of tumour necrosis of this new combined therapy with those obtained in a matched population treated with TACE alone in a singlestep treatment in our centre in the previous year.

Methods and materials

This pilot study was approved by the institutional review board, and informed consent was obtained from all patients. Ten consecutive patients with multinodular (two to six nodules) unilobar unresectable HCC and with a main target lesion >3 cm (range, 3.5–6 cm) not suitable for curative therapy were enrolled in our single-centre multidisciplinary pilot study. The schedule consisted of percutaneous RFA (single 3-cm monopolar needle insertion) of the target lesion during occlusion of the hepatic artery supplying the tumour, followed by selective TACE, plus lobar TACE for other lesions (450-mg carboplatin and lipiodol plus temporary embolisation with SPONGOSTAN). Adverse events and intra- and periprocedural complications were clinically assessed. Early local efficacy was evaluated on 1-month follow-up multiphasic computed tomography (CT) on the basis of the Modified Response Evaluation Criteria in Solid Tumors (m-RECIST). A separate evaluation of target lesions in terms of enhancement, necrotic diameter and presence and distribution of lipiodol uptake was also performed.

Results

No major complications occurred. Overall technical success, defined as complete devascularisation of all nodules during the arterial phase, was achieved in seven of 10 patients, with three cases of partial response (persistence of small hypervascular nodules). When considering only target lesions, technical success was obtained in all patients, with a nonenhancing area corresponding in shape to the previously identified HCC (necrotic diameter, 3.5–5 cm) and with circumferential peripheral lipiodol uptake (safety margin) of at least 0.5 cm (0.5–1.3cm).

Conclusions

TACE and BO-RFA, plus TACE in a singlestep approach seems to be a safe and effective combined therapy for treating advanced, unresectable HCC lesions, allowing a high rate of complete local response to be achieved in large lesions also.  相似文献   
47.
Background Voice and swallowing symptoms are frequently reported after thyroidectomy even in absence of objective voice alterations. We evaluated the influence of the video-assisted approach on voice and swallowing outcome of thyroidectomy. Methods Sixty-five patients undergoing total thyroidectomy (TT) were recruited. Eligibility criteria were: nodule size ≤30 mm, thyroid volume ≤30 ml, no previous neck surgery. Exclusion criteria were: younger than aged 18 years and older than aged 75 years, vocal fold paralysis, history of voice, laryngeal or pulmonary diseases, malignancy other than papillary thyroid carcinoma. Patients were randomized for video-assisted (VAT) or conventional (CT) thyroidectomy. Videostrobolaryngoscopy (VSL), acoustic voice analysis (AVA), and maximum phonation time (MPT) evaluation were performed preoperatively and 3 months after TT. Subjective evaluation of voice (voice impairment score = VIS) and swallowing (swallowing impairment score = SIS) were obtained preoperatively, 1 week, 1 month, and 3 months after TT. Results Fifty-three patients completed the postoperative evaluation: 29 in the VAT group, and 24 in the CT group. No laryngeal nerves injury was shown at postoperative VSL. Mean postoperative MPT, F 0, F low, F high, and the number of semitones were significantly reduced in the CT group but not in the VAT group. Mean VIS 3 months after surgery was significantly higher than preoperatively in CT group but not in the VAT group. Mean SIS was significantly decreased 1 and 3 months after VAT but not after CT. Conclusions The incidence and the severity of early voice and swallowing postthyroidectomy symptoms are significantly reduced in patients who undergo VAT compared with conventional surgery. Presented at the ISW2007—IAES free paper session, Montreal, Canada, August 26–30, 2007.  相似文献   
48.
An exceptional case of tracheal agenesis with no communication with the esophagus is described. This malformation needs surgical airway approach and is hardly classifiable. We analyzed the literature and our institutional data: this resulted to be the first case of such anatomical variant. Genetic and pathological issues are reviewed: recent genetic data seem to explain this malformation. We also reviewed the available literature about prenatal presentation. Because prenatal diagnosis is difficult to achieve and current guidelines for neonatal resuscitation do not provide any recommendation, the resuscitative team may not be prepared for managing such a case. Usefulness of uncommon resuscitative maneuvers is discussed: a promptly performed surgical tracheotomy is the only mean to ventilate such a baby.  相似文献   
49.
Background  Roentgenographic and functional outcomes of expandable self locking intramedullary nailing and platelet rich plasma (PRP) gel in the treatment of long bone non-unions are reported. Materials and methods  Twenty-two patients suffering from atrophic diaphyseal long bone non-unions were enrolled in the study. Patients were treated with removal of pre-existing hardware, decortication of non-union fragments, and fixation of pseudoarthrosis with expandable intramedullary nailing (Fixion™, Disc’O Tech, Tel Aviv, Israel). At surgery, PRP was placed in the pseudoarthrosis rim. Results  The thirteen-month follow-up showed 91% (20/22 patients) of patients attaining bony union. The average time to union was 21.5 weeks. No infection, neurovascular complication, rotational malalignment, or limb shortening >4 mm were observed. The healing rate of non-unions was comparable to that observed in previous studies but with a lower complication frequency. Conclusions  The combined use of self locking intramedullary nailing and PRP in the management of atrophic diaphyseal long bone non-unions seems to produce comparable results with less complications than previously reported. Further data are warranted to investigate the single contribution of PRP gel and Fixion nail.  相似文献   
50.
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