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91.

Aims

Our aim was to evaluate the activity, toxicity, and feasibility of electrochemotherapy (ECT) in patients with soft-tissue sarcomas (STS).

Methods

A two-stage phase II trial was conducted between October 2006 and March 2012. Patients (N = 34) with locally advanced or metastatic STS, unsuitable for standard oncological treatments and with maximum 3-cm deep tumors, received an intravenous bolus of bleomycin (15,000 IU/m2), followed by tumor electroporation according to the European Standard Operating Procedures of ECT. Outcome measures included local response according to response evaluation criteria in solid tumors (RECIST), toxicity and tumor control. Feasibility measures included the accuracy of electrode placement and the intensity of electric current flowing in tumor tissue.

Results

Median tumor size was 4.0 cm (range 2–12). Objective response, assessed on 71 target lesions, was 92.2 % (complete 32.3, 95 % CI 28–64). A total of 15 patients received up to four cycles due to incomplete response, but re-treatment did not significantly improve outcome (p = 0.205). After a median follow-up of 19.3 months, 2-year local control rate was 72.5 %. Median time to local failure (N = 11 patients) was 5.1 months. Tumor response (p = 0.041) and control (p = 0.047) correlated with histological grading. Relevant toxicity consisted of G3 skin ulceration and soft tissue necrosis (35 and 23 % of patients, respectively), although this was manageable on an outpatient basis. The accuracy of electrode placement was 47.1 %, and the adequacy of electroporative current 85.3 %.

Conclusions

ECT may represent an active and safe treatment to achieve local control in advanced STS patients with symptomatic disease. Future research challenges include the improvement of electrode placement and voltage delivery together with the containment of soft tissue toxicity.  相似文献   
92.
Stem cells have huge applications in the field of tissue engineering and regenerative medicine. Their use is currently not restricted to the life-threatening diseases but also extended to disorders involving the structural tissues, which may not jeopardize the patients’ life, but certainly influence their quality of life. In fact, a particularly popular line of research is represented by the regeneration of bone and cartilage tissues to treat various orthopaedic disorders. Most of these pioneering research lines that aim to create new treatments for diseases that currently have limited therapies are still in the bench of the researchers. However, in recent years, several clinical trials have been started with satisfactory and encouraging results. This article aims to review the concept of stem cells and their characterization in terms of site of residence, differentiation potential and therapeutic prospective. In fact, while only the bone marrow was initially considered as a “reservoir” of this cell population, later, adipose tissue and muscle tissue have provided a considerable amount of cells available for multiple differentiation. In reality, recently, the so-called “stem cell niche” was identified as the perivascular space, recognizing these cells as almost ubiquitous. In the field of bone and joint diseases, their potential to differentiate into multiple cell lines makes their application ideally immediate through three main modalities: (1) cells selected by withdrawal from bone marrow, subsequent culture in the laboratory, and ultimately transplant at the site of injury; (2) bone marrow aspirate, concentrated and directly implanted into the injury site; (3) systemic mobilization of stem cells and other bone marrow precursors by the use of growth factors. The use of this cell population in joint and bone disease will be addressed and discussed, analysing both the clinical outcomes but also the basic research background, which has justified their use for the treatment of bone, cartilage and meniscus tissues.  相似文献   
93.
94.

INTRODUCTION

Bochdalek hernia presentation in adulthood is rare. The presentation in newborns is the most common, manifesting with data from respiratory failure secondary to pulmonary hypoplasia, requiring urgent surgical intervention with high morbidity and mortality.

PRESENTATION OF CASE

We present the case of a 33 year old woman admitted in the emergency room with severe abdominal pain in the left upper quadrant and disnea. After physical examination and laboratory test we diagnose mild acute pancreatitis. The patient haven’t colelitiasis by ulstrasound or any risk factor for pancreatitis. Initially she received medical treatment and was discharged after one week. After four weeks she presented the same symptoms in two different occasions, with severe and mild pancreatitis respectively. A computed tomography report a left posterolateral diafragmatic hernia. In spite of the rare association of pancreatitis and Bochdalek hernia, we realized it as the etiology until the second event and planned his surgery. We made a posterolateral torachotomy and diafragmatic plasty with a politetrafluoroetileno mesh and after a 6 months follow up she has coursed asymptomatic.

DISCUSSION

The high rate of complications in this type of hernia requires us to perform surgical treatment as the hernia is detected. In this case it is prudent medical treatment prior to surgical correction despite this being the origin of the pancreatitis, because the systemic inflammatory response added by the surgical act could result in a higher rate of complications if not performed at the appropriate time. There is no precise rule to determine the type of approach of choice in this type of hernia which thoracotomy or laparotomy may be used.

CONCLUSION

Bochdalek hernia is a rare find in adults who require treatment immediately after diagnosis because of the high risk of complications. When presented with data from pancreatitis is recommended to complete the medical treatment of pancreatitis before surgery to obtain the best results, unless it exist another abdominal complication.  相似文献   
95.
96.

Background

Shoulder arthroscopy is not common in the pediatric and adolescent population, but the frequency may be on the rise. The purpose of the study was to determine the incidence of acute complications of arthroscopic shoulder surgery in children and adolescents.

Methods

A retrospective, cross-sectional review was performed identifying patients aged 18 years or less who underwent an arthroscopic shoulder procedure from 1997 to 2009 at Institution 1 and 2007 to 2010 at Institution 2. Exclusion criteria included open procedures and missing records. Demographic and surgical data were collected, including intra-operative and post-operative complications during the first 6 months. The complications were divided into minor (no secondary treatment) and major (secondary treatment rendered).

Results

Two hundred children, mean age 15.9 years, met criteria and 73 % were boys. All procedures were performed under general anesthesia, but 51 % included inter-scalene regional anesthesia. There were 16 (8.0 %) total complications recorded. Major complications occurred in five (2.5 %) patients, including two tendinitis/bursitis requiring injections, one broken pain pump catheter requiring an accessory incision to retrieve, one pain control readmission, and one laceration of the cephalic vein requiring ligation. Minor complications occurred in 11 (5.5 %) patients, including allergic reactions, transient dysesthesias, headaches, bronchitis, syncope, transient hypotension, and uvula swelling.

Conclusion

Although we found no seriously deleterious outcomes, it is important to recognize that an additional service was rendered for 2.5 % of children undergoing shoulder arthroscopy. The events that did occur may be preventable and this study should serve as a baseline to improve quality and safety of shoulder arthroscopy in the pediatric population.  相似文献   
97.
98.
OBJECTIVE: To perform a molecular autopsy involving the RyR2-encoded cardiac ryanodine receptor/calcium release channel to determine whether mutations responsible for catecholaminergic polymorphic ventricular tachycardia (CPVT) represent a novel pathogenic basis for unexplained drownings. METHODS: A cardiac channel molecular autopsy was performed on 2 individuals who died of unexplained drowning and whose cases were referred to the Sudden Death Genomics Laboratory at the Mayo Clinic in Rochester, Minn. Comprehensive mutational analysis of all 60 protein-encoded exons of the 5 long QT syndrome-causing cardiac channel genes and a targeted analysis of 18 RyR2 exons known to host RyR2-mediated CPVT-causing mutations (CPVT1) was performed using polymerase chain reaction, denaturing high-performance liquid chromatography, and DNA sequencing. RESULTS: Both individuals harbored novel mutations in RyR2. Postmortem mutational analysis revealed a familial missense mutation in exon 14, R414C, in a 16-year-old girl. A 9-year-old boy possessed a sporadic missense mutation in exon 49, V2475F. Both amino acid positions involve highly conserved residues that localize to critical functional domains in the calcium release channel. Neither substitution was present in 1000 reference alleles. CONCLUSIONS: This molecular autopsy study provides proof of principle that RyR2 mutations can underlie some unexplained drownings. A population-based genetic epidemiology study that involves molecular autopsies of individuals who die of unexplained drowning is needed to determine the prevalence and spectrum of KCNQ1 and now RyR2 mutations as potential pathogenic mechanisms for drowning.  相似文献   
99.
OBJECTIVE: Insulin reduces morbidity and mortality among critically ill patients, but the molecular mechanisms of its effect remain unknown. Insulin is a well-known inhibitor of glycogen synthase kinase-3, which may play an important role in systemic inflammation and shock. Here we investigate the role of blood glucose and glycogen synthase kinase-3beta inhibition in the protective effect of insulin on the organ injury/dysfunction associated with excessive systemic inflammation. DESIGN: Prospective, randomized study. SETTING: University-based research laboratory. SUBJECTS: Eighty-five anesthetized Wistar rats. INTERVENTIONS: Rats received Escherichia coli lipopolysaccharide (1 mg/kg) and Staphylococcus aureus peptidoglycan (0.3 mg/kg) or vehicle intravenously. Insulin (1.4 units/kg intravenously) was administered in the absence or presence of continuous glucose administration (4.5 mg/kg/hr intravenously) either prophylactically or therapeutically. The potent and selective glycogen synthase kinase-3beta inhibitor TDZD-8 (1 mg/kg intravenously) or vehicle (10% dimethyl sulfoxide) was administered either prophylactically or therapeutically. MEASUREMENTS AND MAIN RESULTS: Coadministration of lipopolysaccharide and peptidoglycan resulted in increases in the serum levels of creatinine (indicator of renal dysfunction), alanine aminotransferase, and aspartate aminotransferase (indicators of liver injury) at 6 hrs. Insulin or TDZD-8 similarly attenuated the organ injury/dysfunction caused by lipopolysaccharide and peptidoglycan when given either prophylactically or therapeutically. Continuous glucose administration had no effect on blood glucose levels or organ injury/dysfunction at 6 hrs. Treatment with insulin or TDZD-8 reduced the plasma levels of the proinflammatory cytokine interleukin-1beta. In vitro, insulin or TDZD-8 caused similar reductions in the nuclear factor-kappaB p65 activity and similar increases in the phosphorylation of Ser9 of glycogen synthase kinase-3beta. CONCLUSIONS: Therapy with insulin or the potent and selective glycogen synthase kinase-3beta inhibitor TDZD-8 reduced the organ injury/dysfunction caused by lipopolysaccharide and peptidoglycan in the rat. We propose that the inhibitory effect of insulin on the activity of glycogen synthase kinase-3beta contributes to the protective effect of insulin against the organ injury/dysfunction caused by excessive systemic inflammation independently of any effects on blood glucose.  相似文献   
100.
Constitutive AmpC hyperproduction is the most frequent mechanism of resistance to the weak AmpC inducers antipseudomonal penicillins and cephalosporins. Previously, we demonstrated that inhibition of the β-N-acetylglucosaminidase NagZ prevents and reverts this mechanism of resistance, which is caused by ampD and/or dacB (PBP4) mutations in Pseudomonas aeruginosa. In this work, we compared NagZ with a second candidate target, the AmpG permease for GlcNAc-1,6-anhydromuropeptides, for their ability to block AmpC expression pathways. Inactivation of nagZ or ampG fully restored the susceptibility and basal ampC expression of ampD or dacB laboratory mutants and impaired the emergence of one-step ceftazidime-resistant mutants in population analysis experiments. Nevertheless, only ampG inactivation fully blocked ampC induction, reducing the MICs of the potent AmpC inducer imipenem from 2 to 0.38 μg/ml. Moreover, through population analysis and characterization of laboratory mutants, we showed that ampG inactivation minimized the impact on resistance of the carbapenem porin OprD, reducing the MIC of imipenem for a PAO1 OprD mutant from >32 to 0.5 μg/ml. AmpG and NagZ targets were additionally evaluated in three clinical isolates that are pan-β-lactam resistant due to AmpC hyperproduction, OprD inactivation, and overexpression of several efflux pumps. A marked increase in susceptibility to ceftazidime and piperacillin-tazobactam was observed in both cases, while only ampG inactivation fully restored wild-type imipenem susceptibility. Susceptibility to meropenem, cefepime, and aztreonam was also enhanced, although to a lower extent due to the high impact of efflux pumps on the activity of these antibiotics. Thus, our results suggest that development of small-molecule inhibitors of AmpG could provide an excellent strategy to overcome the relevant mechanisms of resistance (OprD inactivation plus AmpC induction) to imipenem, the only currently available β-lactam not significantly affected by P. aeruginosa major efflux pumps.  相似文献   
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