Thermoplastic clear dental aligners under cyclic compression loading: A mechanical performance analysis using acoustic emission technique

The objective of this work is to analyse the performance of clear aligners made of thermoplastic materials. Within this framework, the damage evolution stages and damage states of the aligners at different cycles of the compressive loading are evaluated using the Acoustic Emission (AE) technique. Three different clear aligner systems were prepared: thermoformed PET-g (polyethylene terephthalate glycol) and PU (polyurethane), and additively manufactured PU. Cyclic compression tests are performed to simulate 22500 swallows. The mechanical results show that the energy absorbed by the thermoformed PET-g aligner remains stable around 4 Nmm throughout the test. Although the PU-based aligners show a higher energy absorption of about 7 Nmm during the initial phase of the cyclic loading, this gradually decreases after 12500 cycles. The time-domain based, and frequency-based parameters of the stress wave acoustic signals generated by the aligners under compression loading are used to identify the damage evolution stages. The machine learning-based AE results reveal the initiation and termination of the different damage states in the aligners and the frequency-based results distinguish the different damage sources. Finally, the microscopy results validated the damage occurrences in the aligners identified by the AE results. The mechanical test results indicate that the thermoformed PET-g has the potential to match the performance and requirements of the dentistry of the popular Invisalign (additively manufactured PU). The AE results have the potential to identify at which cycles the aligners may start losing their functionality.

A Neural Network Framework for Validating Information-Theoretics Parameters in the Applications of Acoustic Emission Technique for Mechanical Characterization of Materials

A multiparameter approach is preferred while utilizing Acoustic Emission (AE) technique for mechanical characterization of composite materials. It is essential to utilize a statistical parameter, which is independent of the sensor characteristics, for this purpose. Thus, a new information-theoretics parameter, Lempel-Ziv (LZ) complexity, is used in this research work for mechanical characterization of Carbon Fibre Reinforced Plastic (CFRP) composites. CFRP specimens in plain weave fabric configurations were tested and the acoustic activity during the loading was recorded. The AE signals were classified based on their peak amplitudes, counts, and LZ complexity indices using k-means++ data clustering algorithm. The clustered data were compared with the mechanical results of the tensile tests on CFRP specimens. The results show that the clustered data are capable of identifying critical regions of failure. The LZ complexity indices of the AE signal can be used as an AE descriptor for mechanical characterization. This is validated by studying the clustered signals in their time-frequency domain using wavelet transform. Finally, a neural network framework based on SqueezeNet was trained using the wavelet scalograms for a quantitative validation of the data clustering approach proposed in this research work. The results show that the proposed method functions at an efficiency of more than 85% for three out of four clustered data. This validates the application of LZ complexity as an AE descriptor for AE signal data analysis.

Damage Propagation Analysis in the Single Lap Shear and Single Lap Shear-Riveted CFRP Joints by Acoustic Emission and Pattern Recognition Approach

An innovative way of using the Acoustic Emission (AE) technique is introduced in this research work. The ratio of recorded acoustic energy and the counts recorded for each acoustic event were used for characterizing Carbon Fiber Reinforced Plastic (CFRP) laminates adhesively bonded with and without mechanical fasteners. The cumulative counts and cumulative energy of the recorded acoustic events were used for identifying the critical points of failure under loading of these hybrid joint specimens. The peak amplitude distribution was used for identifying the different damage modes such as delamination, matrix cracking and fiber breakage, albeit, ineffectively. The new parameter energy per count was introduced in this work, which can successfully identify the different damage modes under loading. To differentiate the damage modes using the energy per count, they were clustered using k-means++ pattern recognition technique. The method introduced in this work can estimate the damage modes of the CFRP specimens.

Thermomechanical and Morphological Studies of CFRP Tested in Different Environmental Conditions

The present work describes the mechanical characterization combined with the thermal degradation kinetics of Carbon Fiber Reinforced Polymers (CFRP). The thermal degradation kinetics of CFRP have never been studied in the past. In that regard, the present work focuses on studying the thermal degradation kinetics of CFRP tested mechanically at different environmental conditions. Tensile tests were performed on the specimens with different lay-ups at room temperature, elevated temperature (71 °C), and cryogenic conditions (−54 °C), and the same specimens were used for thermal degradation kinetic studies. Mechanical tests show different responses respect to the different environmental conditions and different fibers orientation. On the other hand, the thermogravimetric results, mass loss, and derivative mass loss, show no significant difference in the degradation of CFRP tested at different temperatures. However, the thermal degradation kinetics shows more insight into the degradation pattern of the materials. The activation energy of degradation shows that the degradation of materials subjected to elevated conditions increases rapidly in the later stages of degradation, suggesting the formation of high char yield. The varying activation energy has been related to different degradation mechanisms. Lastly, the morphology of the materials was studied under SEM to understand the structural change in the material after tested in different weather conditions.

Predictive genetic markers in neoadjuvant chemoradiotherapy for locally advanced esophageal cancer: a long way to go. Review of the literature

The role of genetic molecular markers in neoadjuvant treatment for locally advanced esophageal cancer has been reviewed, focusing strictly on concurrent chemoradiation protocols followed by surgery. Eleven studies evaluated the role of mRNA expression profile; the end point was overall survival (OS) in two studies and different definitions of histological response in nine. Genes reported as significant were involved in cell cycle control (30), apoptosis (7), structural molecules (9), cell metabolism (6) and DNA repair (1). Seven studies reported about 15 microRNA (miRNA) molecules associated with OS (2) or histological response (13), however, defined with different classifications. Their target genes were prevalently involved in cell cycle control (4), apoptosis (1), cell adhesion (1), migration (1) and angiogenesis (1). Gene polymorphisms (single-nucleotide polymorphisms (SNPs)) have been evaluated in 8 studies reporting 10 variants associated with survival or pathological response. OS was the end point in six of these studies. SNPs reported as significant were involved in DNA repair system (4), detoxification (2), folate metabolism (6), drug efflux (2) and others (2). In a study, a panel including histology, pathological response and five SNPs discriminated two subsets of patients with 5-year survival rates of 79.3% and 26.3% (hazard ratio 6.25, P<0.0001). In another study, combination of stage, grade and 4 miRNAs improved prediction of pathological response (P=10^-30). At present, given the great inconsistency of the data and the variability of the end points, definite conclusions are extremely difficult, if not impossible. More consistent data can derive only from analyses obtained from patients included in prospective randomized trials while panels combining genetic and clinical factors may improve prediction.

Safety and activity of sunitinib in elderly patients (≥ 70 years) with metastatic renal cell carcinoma: a multicenter study

BACKGROUND

Actual tolerability of sunitinib is still poorly documented in elderly patients with metastatic renal cell carcinoma (mRCC).

PATIENTS AND METHODS

Charts of elderly patients treated with sunitinib for mRCC were reviewed in six Italian centers to assess safety (primary objective), efficacy and correlation of toxicity with comprehensive geriatric assessment (CGA) (secondary objectives).

RESULTS

Sixty-eight patients were eligible, and the median age was 74 years. CGA was carried out in 34 patients (41% fit, 41% vulnerable and 18.5% frail). The dose reduction to 37.5 mg was made upfront or soon after the first cycle in 69.1%. More frequent toxic effects were fatigue (80.9%), mucositis (61.8%) and hypertension (58.8%). Cardiac events occurred in nine patients. In 10 patients, therapy was interrupted early due to rapidly progressive disease (10.3%) or severe toxicity (4.4%: 1 cardiac failure, 1 fatigue, 1 febrile neutropenia). At a median follow-up of 27.1 months, the median OS was 18.3 months and the median PFS was 13.6 months. Correlation was not found between frailty at CGA with severe toxicity nor with response.

CONCLUSIONS

Treatment with sunitinib is effective in elderly patients; yet early interruptions were frequent. Starting treatment at reduced dose and escalating in the absence of severe toxicity could be suggested.

Phorbol 12-myristate 13-acetate (pma) induces neuroendocrine-like differentiation and reverses Doxorubicin-resistance of human colon-carcinoma cells in-vitro

Human colon carcinoma LoVo/DX cells, which have been selected from parental LoVo for resistance to doxorubicin, express a typical multidrug resistant (MDR-1) phenotype. We have investigated whether phorbol 12-myristate 13-acetate (PMA) which often induces phenotypical changes in human tumor cells could, at the same time, modulate differentiation and sensitivity of LoVo/DX cells to doxorubicin. After 48 h exposure to 100 nM PMA, morphological changes became evident on LoVo/DX cells which showed elongated cytoplasm and dendritic-like structures: moreover immunocytochemical findings were suggestive of neuroendocrine-like differentiation. Under the same experimental conditions, LoVo/DX became sensitive to doxorubicin and showed enhanced intracellular drug-accumulation and reduced membrane expression of the 170 kD glycoprotein GP-170, which is the cellular product of the mdr1 gene. We conclude that pharmacological induction of tumor cell differentiation by PMA is paralleled by abrogation of drug resistance in a colon carcinoma MDR-1 cell line.

Efficacy of pegylated liposomal doxorubicin (PLD) and oxaliplatin (Ox) in pre-treated advanced epithelial ovarian cancer (EOC) in relation to BRCA status

16006

Background: The mechanism of action of PLD+Ox suggests that and carriers of BRCA mutations might have better survival compared to sporadic ovarian cancer even when pre-treated in advanced EOC. Methods: Inclusion criteria: Performance Status<=2, relapse or progression after 1–3 lines of therapy; <=4 prior antiblastic drugs; life expectancy >3 months; LVEF >50%, informed consent. Treatment consisted of 1 hr infusion of PLD 30–35 mg/m2 on day 1 and 70 mg/m2 of Ox in 2 hrs on day 2 for 8 cycles, then 2 cycles of PLD alone. Clinical response was evaluated by CT scan every 3 cycles. Primary endpoints were overall survival and its correlation with BRCA mutations and p53. Results: From June 2000, 63 pre-treated pts with advanced EOC were enrolled. Median age = 62 yrs, range 41–83, (18pts >70 yrs). 17 had known germline BRCA1/2 mutations (10pts) or family history of ovarian cancer (4pts). In this BRCA/high-risk population 15 pts were evaluable for response with ORR=93.3% (8 CR, 6 PR>50%, 1 SD). 139 courses were administered (median = 10 courses/pt). There was 1 episode of G3 toxicity: mucositis; G1–2 toxicity was gastrointestinal (16 episodes), mucositis (11 episodes), neutropenia (9 episodes). Median LVEF showed no significant changes during treatment. There is no clear correlation between OS and amount of Platinum/Taxol administered previously. p53 was analyzed for expression and mutations. Mutations were sought in exons 5, 6, 7 and 8. 5/6 CR evaluable for p53 showed overexpression. p53 overexpression was seen in 9/11 evaluable pts; of these 4/9 also had p53 mutations. 3/4 of these patients obtained a complete response. Median survival from 1st cycle has not been reached; mean survival is 63.6 months vs 24.7 for sporadic EOC (p<.001). Presently 15/17 are alive. The 5-yr survival after first course of therapy is estimated at 82%. BRCA/high-risk patients in PLD-Ox therapy also fared better than counterparts from an historical population (OS from diagnosis 179.4 vs 141.1 months, p=.005). Conclusions: PLD+Ox is well tolerated and highly effective in BRCA/high-risk patients and in p53 positive/mutated pts in this population. This therapy offers low toxicity providing good quality of life.

No significant financial relationships to disclose.

Pharmacokinetic and demographic markers of 5-fluorouracil toxicity in 181 patients on adjuvant therapy for colorectal cancer

BACKGROUND

The relationship between 5-fluorouracil (5-FU) pharmacokinetics and toxicity following i.v. bolus administration has not been extensively studied.

PATIENTS AND METHODS

One hundred and eighty-one patients on adjuvant therapy with 5-FU plus leucovorin for colorectal cancer were the study population. 5-FU pharmacokinetics was determined on day 2 of the first, third, and fifth cycles; type and the grade of adverse reactions were recorded on the next cycle.

RESULTS

The 5-FU area under the curve (AUC) measured at the first cycle ranged between 146 and 1236 mg x min/l and was significantly correlated with drug dose, patients' body weight (BW) and gender, females having higher AUCs. These covariates explained only 23% of AUC variability. AUC and age were the only covariates which discriminated between toxic (grade > or =2) and nontoxic cycles (grade <2), with an optimal AUC cut-off value of 596 mg x min/l. Such a correlation was lost during the next cycles following dose reduction because of toxicity in 80 patients.

CONCLUSIONS

A method for calculating the initial 5-FU dose is proposed which takes into account patient BW, gender and a target AUC of 596 mg x min/l. Nevertheless, it appears that a substantial part of 5-FU toxicity is not linked to pharmacokinetic factors and dose adjustments must still be on the basis of careful clinical surveillance.

Efficacy of pegylated liposomal doxorubicin (PLD) and oxaliplatin (OX) in pre-treated advanced epithelial ovarian cancer (EOC) and relation to p53 status

15054

Background: The efficacy of PLD+Ox in pre-treated advanced EOC in third and fourth line suggests that the elevated survival in these patients might activate the p53 pathway. Methods: Inclusion criteria: Performance Status≤2, relapse or progression after 1–3 lines of therapy; ≤4 prior antiblastic drugs; life expectancy >3 months; LVEF >50%.Treatment consisted of 1 hr infusion of PLD 30–35 mg/m2 on day 1 and 70 mg/m2 of Ox in 2 hrs on day 2 for 8 cycles, then 2 cycles of PLD alone. Clinical response was evaluated by CT scan every 3 cycles. Primary endpoints were overall survival and its correlation with p53. Results: From June 2000, 65 pre-treated pts were enrolled. They were divided according to platinum sensitivity into sens, part-sens and res (time to progression after platinum therapy of ≥12, ≥6 or <6 months). Median age = 65 yrs, range 41–84, (23 pts >70 yrs). 56 pts were evaluable for response: 28 sens with an ORR = 79%, 15 part-sens ORR = 47%, and 12 res ORR = 50%. 445 cycles were administered (median = 6 cycles/pt). Median survival from 1st cycle was 19 months, 10 and 8 months in sens and part-sens and res groups respectively (p = 0.00021). Major (G3–4) toxicities were: neutropenia (6 episodes), gastrointestinal (3 episodes). G1–2 neurosensorial toxicity was seen in 18 pts and PPE in 10 pts. 1 toxic-related death was recorded. Median LVEF showed no significant changes during treatment. There is no clear correlation between OS and amount of Platinum/Taxol administered previously. p53 was analyzed for expression and mutations. Mutations were sought in exons 5, 6, 7 and 8. Immunohistochemistry of 11 amplified samples showed p53 overexpression in 8 pts, of these 7/11 had a CR and/or PR (64%). The analysis is ongoing. The 5-yr survival after first relapse is 64%, 24% and 0% for sens, part-sens and res respectively. 6/6 (100%) evaluable patients with BRCA mutations responded to therapy (5 BRCA1 pts, 1 BRCA2 pt): 4 CR and 2 PR, presently all living. Conclusions: The therapy is effective in increasing OS in Platinum-sensitive patients after re-exposure to Carboplatin and Taxol and may be effective in p53+/mutated pts and for pts with BRCA mutation. For Pt-refractory and Pt-partially-sensitive pts an optimized use of this treatment must be identified.

No significant financial relationships to disclose.

Role of 18F-FDG PET–CT imaging for the detection of an unknown primary tumour: preliminary results in 21 patients

PURPOSE

Metastatic cancer of unknown primary origin is a syndrome characterised by a poor prognosis, with a typical survival rate from diagnosis of no longer than 1 year. Only 20-27% of primary tumours are identified by conventional radiological imaging. By contrast, it has been reported that 18F-fluorodeoxyglucose positron emission tomography (FDG PET) allows the identification of 24-40% of otherwise unrecognised primary tumours. To our knowledge, the studies on this topic have been conducted using 18F-FDG PET imaging alone. The aim of this study was to evaluate the potential additional diagnostic role of fused 18F-FDG PET-CT imaging for the detection of metastatic occult primary tumours.

METHODS

The study population consisted of 21 consecutive patients with biopsy-proven metastatic disease and negative conventional diagnostic procedures. Each patient underwent a PET scan, carried out according to a standard procedure (6 h of fasting, i.v. injection of 370 MBq of 18F-FDG and image acquisition with a dedicated PET-CT scanner for 4 min per bed position).

RESULTS

18F-FDG PET-CT detected the occult primary tumour in 12 patients (57% of cases), providing a detection rate higher than that reported with any other imaging modality, including conventional 18F-FDG PET.

CONCLUSION

The favourable results of this study need to be confirmed in larger patient populations with long-term follow-up.

Daily low-dose subcutaneous recombinant interleukin-2 by alternate weekly administration: antitumor activity and immunomodulatory effects

A phase II clinical trial of subcutaneous recombinant Interleukin 2 (rIL-2) given by 5 days pulses followed by a 9 days rest has been performed in patients affected by renal cell carcinoma, malignant melanoma and colorectal cancer. A total of 25 patients entered the study, completed at least six courses of treatment, and were evaluable for toxicity and response to treatment. This schedule of subcutaneous rIL-2 was well tolerated and no World Health Organization grade 3 side effects were observed. A 33.3% response rate was recorded in patients affected by renal cell carcinoma, although no major responses were achieved in patients with malignant melanoma and colorectal cancer. A durable increase of natural killer activity retained by poeripheral blood mononuclear cells was demonstrated in these patients and was paralleled by increased serum levels of interferon gamma and tumor necrosis factor a without changes of circulating interleukin-1d. It is concluded that this schedule of pulse administration of subcutaneous rIL-2 has antitumor activity in renal cell carcinoma and produces durable biomodulatory effects.

Alpha-interferon induces depletion of intracellular iron content and upregulation of functional transferrin receptors on human epidermoid cancer KB cells

We have demonstrated that interferon-alpha (IFN alpha) upregulates the epidermal growth factor receptor (EGF-R) on human epidermoid carcinoma cells. Here we report that IFN alpha induces growth inhibition and upregulation of transferrin receptor (TRF-R) on epidermoid cancer KB cells. IFN alpha does not alter TRF-R affinity for its ligand and induces a two-fold increase of TRF binding sites. IFN alpha does not modify receptor internalization and cycling. Intracellular iron levels are known to regulate TRF-R expression: we have, therefore, evaluated whether changes in the iron content could be determined by IFN alpha. Iron levels are transiently increased after addition of fresh growth medium in untreated controls but not in KB cells exposed for 48 h to IFN alpha. Iron depletion is however completely reversed 24 h later when maximal TRF-R upregulation occurs in IFN alpha-treated cells. We suggest that IFN alpha-induced iron depletion elicits a homeostatic cellular response through upregulation of TRF-R.

Cardiovascular monitoring of drug-resistant lymphoma patients treated with epoch chemotherapy plus high-dose verapamil in continuous-infusion

High dose Verapamil (VP) infusion has been incorporated into cytotoxic chemotherapy in order to circumvent tumor cell drug-resistance. We have evaluated the cardiovascular side-effects produced by high dose VP associated to EPOCH chemotherapy in 12 patients with chemorefractory lymphoma. Continuous monitoring of right ventricular and pulmonary pressure and cardiac index was performed in three patients by a Swan-Ganz catheter. A slight reduction in cardiac index was observed 6 h after the beginning of VP infusion and was followed by spontaneous recovery within 12 h. First degree atrioventricular (AV) block was detected in 6/12 patients. Premature Ventricular Beats (PVB) occurred in one patient, and promptly disappeared after xylocaine administration. All patients experienced mild and transient hypotension, while severe hypotension was observed only in 1 patient, who promptly recovered when VP administration was discontinued. Hypokalemia was detected in 6 patients possibly as a consequence of transient activation of the renin-angiotensin system.

[Venous complications of renal transplantation. Experience with 360 cases]

The Authors report three cases of renal vein thrombosis after transplantation. One of these cases has been successfully admitted to surgical treatment. They point out the pathogenetical features and underline the importance of surgery.

[Arterial complications of renal transplantation. Experience with 360 cases]

The Authors report the arterial complications observed in a 360 kidney transplantations experience. They analyze the etiological, diagnostic and therapeutic features.

[Considerations on 12 cases of mesenteric embolism treated surgically]

Twelve cases of mesenteric artery embolism surgically treated with a surviving rate of 66% are reported. The Authors point out the diagnostic features and the various factors affecting the surgical result.

[Inflammatory aneurysms of the abdominal aorta]

The Authors report their fifteen years experience, point out the clinical features of inflammatory abdominal aortic aneurysms and examine the different pathogenetic theories.

[Pseudomembranous colitis caused by antibiotic therapy during aorto-iliac surgery]

Pseudomembranous colitis is not a rare complication of antibiotic therapy. 2000 surgical procedures with implantation of grafts in the aorto-iliac region were performed from 1974 through 1988; during this period 11 cases of CMP were observed. The Authors report their experience in regard to the various antibiotics administered.

[Peripheral nerve injuries during carotid endarterectomy]

Our experience with patients undergoing carotid endoarteriectomy over a 10 year period has been retrospectively reviewed. Nerve injuries were detected by reviewing postoperative progress and clinical notes. One hundred thirty-four procedures were performed on 120 patients, to 15 of whom (9%) occurred major nerve injuries. These included seven vagal nerve injuries causing ipsilateral vocal cord paralysis and hoarseness, five injuries of the marginal mandibular nerve and three injuries of the hypoglossal nerve. None of the patients with nerve injury had a stroke as a result of carotid operation. Vocal cord paralysis was documented by laryngoscopy. The incidence of cranial nerve injury during carotid endoarteriectomy appears to be higher than expected, particularly if asymptomatic patients are controlled.

[Follow-up in femoral artery embolectomy]

The results of 112 femoral embolectomies performed on 100 patients were reviewed. Operative mortality rate was 15% and early amputation (within 30 day-after the procedure) 18%. The role of early amputation was closely related to the time of leg ischemia. Current follow-up as established for 86 patients. 5 years and 10 years survival rates for the group were 49% and 40%. Although early survival is decreased after femoral embolectomy long term survivors can be expected to live independently with excellent limb salvage and function.

[Popliteal aneurysm. Our experience in 65 cases]

Fifty patients with 65 popliteal aneurysms underwent reconstructive procedures (mean age 64). Atherosclerosis is almost the exclusive cause of popliteal aneurysms. Most of the cases showed an acute ischemia, while he others were asymptomatic or presented a complication of venous occlusion or neural compression. Numerous cases were found incidentally at amputations (these were not included). The best operational method is ligation of the aneurysm sometimes with partial resection and autologous venous graft bypass. The immediate results were excellent in all cases, loss of limb was observed in only three.

[An aneurysm of the inferior pancreaticoduodenal artery: a surgically treated case]

Aneurysms of the lower duodenal pancreatic artery are an extremely rare dilatative arterial pathology. Diagnosis is often difficult and rupture is a frequent clinical evolution; surgical therapy, especially when rupture has already occurred, entails a high risk of operative mortality. A case is described of aneurysm of the lower duodenal pancreatic artery which was treated by elective surgery with good results.

[Aneurysms of the abdominal aorta in patients 80 and over years of age. Long term results]

During a thirteen years period 29 patients 80 years of age and older, underwent surgical procedure for abdominal aortic aneurysm. There were 9 elective aortic reconstructions and 20 ruptured abdominal aortic aneurysms (AAA) repairs. Perioperative mortality after elective AAA resection was 33% vs 50% after ruptured AAA (a postoperative period of 30 days was considered). Comparison of survival following aortic reconstruction in 14 patients with survival of general population matched for age, sex and race, is not significant.

[Extra-anatomical bypasses: axillofemoral and femorofemoral. Indications and results]

Indications for a unilateral or bilateral axillofemoral and femorofemoral bypass, are presented. Our experience in 48 patients with axillofemoral and femorofemoral form the basis of this report. Indications for these extended bypasses included suppurative growing infection and obliterated common and profunda femoris arteries. These procedures were rapidly performed in critically ill patients. One patient died of recurrent artoduodenal hemorrhage three days following successful axillofemoral bypass. The other patients enjoyed patent grafts for variable periods, although some of them successfully underwent a declotting procedure.

[Thrombosis of the renal vein after transplantation. Description of a case]

The Authors report a case of renal vein thrombosis after kidney transplantation, which occurred early in the postoperative period and was treated successfully. The treatment is described as are the factors contributing to the good result: early diagnosis and surgical procedure, removal of the transplant and perfusion with cold heparin solution through the artery and the vein, reconstruction of a new vein to vein anastomosis, in a more favorable site.

[Clinical aspects of persistent sciatic artery. Description of 2 cases with angiographic demonstration]

We report 2 additional cases with angiographic demonstration. The embryology and radiological findings are discussed. This anomaly should be kept in mind in the clinical assessment of a patient with unexplained sciatic or buttock pain or a pulsatile buttock mass with or without symptoms of peripheral vascular disease. It also represents a potential hazard during renal transplant surgery.

[Spontaneous rupture of an aneurysm of the abdominal aorta in a jejunal loop]

A case of spontaneous aorto-jejunal fistula treated successfully by surgical management is reported. Diagnostic and therapeutic features as well as the rarity of this uncommon complication of abdominal aortic aneurysms are underlined.

[Extra-anatomical bypass in the treatment of stenotico-obstructive lesions of the subclavian and vertebral arteries]

The haemodynamic premises for extra-anatomical by-pass in the treatment of stenosis and obstructions of the subclavian and vertebral arteries are discussed with a report on a surgically treated series.

[Treatment of acute arterial embolism of the kidney]

The possible ways of treating renal artery embolisms are reviewed with an examination of their advantages and defects. Surgical treatment has a fairly high mortality rate but quickly cures any type of vascular occlusion and will cure any concomitant problems such as arterial stenosis. Medical treatment with anticoagulant or thrombolytic drugs offers a lower short term mortality rate and is effective even on narrow blood vessels but the response varies according to the type of thromboembolic damage and the way the drugs are administered. Recently developed forms of radiological treatment are also examined. A personal technique successfully applied to an embolism in a patient with only one functioning kidney is described. It consists of a two-step mechanical and pharmacological attack. First the occluded artery was opened by means of a balloon catheter that was pushed beyond the embolism and withdrawn into the aorta after inflation of the balloon. Thrombolytic drugs (Urokinase) were then infused through the catheter into the bed of the renal artery in order to cure the secondary thrombosis found, as is generally the case, downstream of the embolism. The technique appears ideal for the treatment of patients with embolisms and total involvement of the renal parenchyma, especially when their general condition makes surgery inadvisable.

High-dose intravenous methylprednisolone in the treatment of multiple sclerosis: clinical-immunologic correlations

We conducted a double-blind trial of high-dose parenteral 6-methylprednisolone (MP) and placebo on 23 patients with acute MS. After the double-blind trial, the patients were given corticosteroids in gradually decreasing doses. The frequency of improvement was significantly higher and the bout duration significantly lower in the MP group than in the placebo group. The first signs of improvement (3 to 6 days after starting MP) were associated with a marked decrease in the rate of CNS IgG synthesis, but IgG CSF oligoclonal bands did not change. CNS IgG production slowly returned toward baseline despite progressive clinical improvement.