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71.

Purpose

Etidocaine (EDC) is a long lasting local anesthetic, which alleged toxicity has restricted its clinical use. Liposomes can prolong the analgesia time and reduce the toxicity of local anesthetics. Ionic gradient liposomes (IGL) have been proposed to increase the upload and prolong the drug release, from liposomes.

Methods

First, a HPLC method for EDC quantification was validated. Then, large unilamellar vesicles composed of hydrogenated soy phosphatidylcholine:cholesterol with 250 mM (NH4)2SO4 - inside gradient - were prepared for the encapsulation of 0.5% EDC. Dynamic light scattering, nanotracking analysis, transmission electron microscopy and electron paramagnetic resonance were used to characterize: nanoparticles size, polydispersity, zeta potential, concentration, morphology and membrane fluidity. Release kinetics and in vitro cytotoxicity tests were also performed.

Results

IGLEDC showed average diameters of 172.3?±?2.6 nm, low PDI (0.12?±?0.01), mean particle concentration of 6.3?±?0.5?×?1012/mL and negative zeta values (?10.2?±?0.4 mV); parameters that remain stable during storage at 4°C. The formulation, with 40% encapsulation efficiency, induced the sustained release of EDC (ca. 24 h), while reducing its toxicity to human fibroblasts.

Conclusion

A novel formulation is proposed for etidocaine that promotes sustained release and reduces its cytotoxicity. IGLEDC can come to be a tool to reintroduce etidocaine in clinical use.
  相似文献   
72.
73.

Background

Late or inadequate therapeutic management increases the risk of mortality associated with HIV/AIDS. The aim of this study was to analyze the proportion and factors associated with loss of follow-up in HIV patients who receiving antiretroviral therapy at Conakry.

Methods

A retrospective cohort study was conducted in HIV patients aged over 15 years and who receiving antiretroviral therapy. Between August 1, 2008 and July 31, 2015, all patients managed by the ambulatory treatment center of the Guinean Women Association against AIDS and sexually and transmissible infection were included. Loss of follow-up was defined as no follow-up visit within 3 months. Kaplan–Meier curves and multivariate Cox regression models were used to analyze factors associated with loss of follow-up. Analyses were performed by using Stata 13 software.

Results

614 patients aged 36.3 ± 11.2 years, mainly females (68.4%) and living in Conakry (80.5%) were included. Among them, 104 were loss to follow-up, corresponding to a proportion rate of 16.9% (95% CI: 14.2–19.7%) or 5.79/100 person-years. The results of multivariate analyses showed that factors independently associated with loss of follow-up were malnutrition (AHR = 7.05; 95% CI: 2.05–24.27; P = 0.002) and CD4 cells account at the initiation of AHR (2.35; 95% CI: 1.61–6.39; P = 0.016) in patients with 201–350 CD4/μL and 5.83 (95% CI: 2.85–11.90; P < 0.001) in patients with less than 150 CD4/μL.

Conclusion

Despite efforts of health care workers and free antiretroviral therapy, many patients were loss to follow-up. Multivariate analysis showed that malnutrition and low CD4 account were independently associated with loss to follow-up.  相似文献   
74.
75.
76.

Background

Although pancreatoduodenectomy (PD) with mesenterico-portal vein resection (VR) can be performed safely in patients with resectable pancreatic ductal adenocarcinoma (PDAC), the impact of this approach on long-term survival is controversial.

Patients and Methods

Analyses of a prospectively collected database revealed 122 consecutive patients with PDAC who underwent PD with (PD+VR) or without (PD?VR) VR between January 2004 and May 2012. Clinical data, operative results, and survival outcomes were analysed.

Results

Sixty-four (53 %) patients underwent PD+VR. The majority (84 %) of the venous reconstructions were performed with a primary end-to-end anastomosis. Demographic and postoperative outcomes were similar between the two groups. American Society of Anesthesiologists (ASA) score, duration of operation, intraoperative blood loss, and blood transfusion requirement were significantly greater in the PD+VR group compared with the PD?VR group. Furthermore, the tumor size was larger, and the rates of periuncinate neural invasion and positive resection margin were higher in the PD+VR group compared with the PD?VR group. Histological venous involvement occurred in 47 of 62 (76 %) patients in the PD+VR group. At a median follow-up of 29 months, the median overall survival (OS) was 18 months for the PD+VR group, and 31 months for the PD?VR group (p = 0.016). ASA score, lymph node metastasis, neurovascular invasion, and tumor differentiation were predictive of survival. The need for VR in itself was not prognostic of survival.

Conclusions

PD with VR has similar morbidity but worse OS compared with a PD?VR. Although VR is not predictive of survival, tumors requiring a PD+VR have more adverse biological features.  相似文献   
77.
78.
Barlow's disease is a complicated form of degenerative mitral valve (MV) disease. Infective endocarditis (IE) often occurs on the basis of primary heart diseases and may be combined with valve perforations. Cleft-like indentations (CLIs) were suggested by Ring et al. in 2013. They are located at the inter-scallop position and involve at least one-half of the valve. Herein, we report a case of Barlow's disease combined with IE and CLIs, which was confirmed intra-operatively and by histopathological examination. The CLIs were misdiagnosed by two-dimensional transthoracic echocardiography as perforations, but rightly interpreted by preoperative three-dimensional echocardiography. The possibility of CLIs should be considered in the evaluation of mitral regurgitation caused by myxomatous MV diseases.  相似文献   
79.
Interleukin-4 (IL-4) is a potent mediator of growth and differentiation of cells of several hematopoietic lineages. Interleukin-5 (IL-5) is a lineage-specific hematopoietic growth factor that stimulates the production of eosinophils and eosinophil colonies from normal human bone marrow cells. By using somatic cell hybrids and in situ chromosomal hybridization, we localized the IL-4 and IL-5 genes to human chromosome 5 at bands q23-31, a chromosomal region that is frequently deleted [del(5q)] in patients with myeloid disorders. By in situ hybridization, the IL-4 and IL-5 genes were found to be deleted in the 5q- chromosome of four patients with refractory anemia (RA) or therapy-related acute nonlymphocytic leukemia (t-ANLL), who had a del(5q). Thus a small segment of chromosome 5 contains IL-4, IL-5, IL- 3, and GM-CSF as well as other genes such as CD14 and EGR1. Our findings that each of these genes was deleted in the 5q- chromosome suggest that loss of function of one or more of these genes may play an important role in the pathogenesis of hematologic disorders associated with a del(5q).  相似文献   
80.
High-dose cytarabine (ara-c) may overcome cytarabine resistance in leukemic blasts. It has been used as a successful salvage and in postremission therapy but not as initial induction treatment. Patients aged 15 to 60 years, presenting with newly diagnosed acute myeloid leukemia (AML) were randomized to receive either high-dose cytarabine, 3 g/m2 12 hourly on days 1, 3, 5, and 7 for 8 doses, daunorubicin 50 mg/m2 days 1 to 3, etoposide 75 mg/m2 days 1 to 7, (HIDAC-3-7) or standard dose cytarabine 100 mg/m2 continuous intravenous infusion for 7 days with daunorubicin and etoposide at the same dose and schedule as above (7-3-7). Patients could receive a second or third induction course if complete remission (CR) was not achieved. All patients received the same postinduction consolidation therapy (5-2-5) for 2 courses. Eligible patients had no prior chemotherapy or myelodysplastic disease. Patients have been followed for a median of 4.5 years. Of 301 patients treated, complete response (CR) was achieved in 71% with HIDAC- 3-7 and 74% with 7-3-7. For patients in CR, the estimated median remission duration was 45 months with HIDAC-3-7 and 12 months with 7-3- 7 (P = .0005 univariate analysis, P = .0004 multivariate analysis). The estimated percentage of patients relapse free 5 years after achieving a CR was 49% on HIDAC-3-7 and 24% on 7-3-7. Patients in CR tended to survive longer with HIDAC-3-7 but there were no overall survival differences between the two arms. HIDAC-3-7 was associated with significantly more toxicity in induction with more leukopenia, thrombocytopenia, nausea, and vomiting and eye toxicity (all P < .001) but a similar incidence of severe central nervous system and cerebellar toxicity compared to 7-3-7. The consolidation treatment was the same in both arms but caused significantly more leukopenia and thrombocytopenia in patients previously treated with HIDAC-3-7 induction (P < .0001). We conclude that a dose-effect exists for cytarabine in AML and that HIDAC- 3-7 prolongs remission duration and disease-free survival and is tolerable when used as initial induction therapy in patients with de novo AML.  相似文献   
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