ITER-like antenna capacitors voltage probes: Circuit/electromagnetic calculations and calibrations.

The analyses illustrated in this manuscript have been performed in order to provide the required data for the amplitude-and-phase calibration of the D-dot voltage probes used in the ITER-like antenna at the Joint European Torus tokamak. Their equivalent electrical circuit has been extracted and analyzed, and it has been compared to the one of voltage probes installed in simple transmission lines. A radio-frequency calibration technique has been formulated and exact mathematical relations have been derived. This technique mixes in an elegant fashion data extracted from measurements and numerical calculations to retrieve the calibration factors. The latter have been compared to previous calibration data with excellent agreement proving the robustness of the proposed radio-frequency calibration technique. In particular, it has been stressed that it is crucial to take into account environmental parasitic effects. A low-frequency calibration technique has been in addition formulated and analyzed in depth. The equivalence between the radio-frequency and low-frequency techniques has been rigorously demonstrated. The radio-frequency calibration technique is preferable in the case of the ITER-like antenna due to uncertainties on the characteristics of the cables connected at the inputs of the voltage probes. A method to extract the effect of a mismatched data acquisition system has been derived for both calibration techniques. Finally it has been outlined that in the case of the ITER-like antenna voltage probes can be in addition used to monitor the currents at the inputs of the antenna.

Analysis of pulmonary non-tuberculous mycobacterial infections after lung transplantation.

PURPOSE: Non-tuberculous mycobacteria (NTM) are important pathogens in lung transplant recipients. This study describes the spectrum of NTM respiratory tract infections and examines the association of NTM infections with lung transplant complications. METHODS: Data from 208 recipients transplanted from November 1990 to November 2005 were analyzed. Follow-up data were available to November 2010. Lung infection was defined by bronchoalveolar lavage, sputum, or blood cultures in the appropriate clinical setting. All identified NTM respiratory tract infections were tabulated. The cohort of patients with NTM lung infections (NTM+) were compared to the cohort without infection (NTM-). Univariate and multivariate analysis was performed to determine characteristics associated with NTM infection. Survival analyses for overall survival and development of bronchiolitis obliterans syndrome (BOS) were also performed. RESULTS: In total, 52 isolates of NTM lung infection were identified in 30 patients. The isolates included Mycobacterium abscessus (46%), Mycobacterium avium complex (MAC) (36%), Mycobacterium gordonae (9%), Mycobacterium chelonae (7%), and Mycobacterium fortuitum (2%), with multiple NTM isolates seen on 3 different occasions. The overall incidence was 14%, whereas cumulative incidences at 1, 3, and 5 years after lung transplantation were 11%, 15%, and 20%, respectively. Comparisons between the NTM+ and NTM- cohorts revealed that NTM+ patients were more likely to be African-American and have cytomegalovirus mismatch. Although no difference was seen in survival, the NTM+ cohort was more likely to develop BOS (80% vs. 58%, P = 0.02). NTM+ infection, however, was not independently associated with development of BOS by multivariate analysis. CONCLUSION: With nearly 20 years of follow-up, 14% of lung recipients develop NTM respiratory tract infections, with M. abscessus and MAC more commonly identified. M. gordonae was considered responsible for nearly 10% of NTM infections. Although survival of patients with NTM infections is similar, a striking difference in BOS rates is present in the NTM+ and NTM- groups.

Probable Phaeoacremonium parasiticum as a cause of cavitary native lung nodules after single lung transplantation.

Lung nodules after lung transplantation most often represent infection or post-transplant lymphoproliferative disorder in the allograft. Conversely, native lung nodules in single lung transplant recipients are more likely to be bronchogenic carcinoma. We present a patient who developed native lung cavitary nodules. Although malignancy was anticipated, evaluation revealed probable Phaeoacremonium parasiticum infection. Phaeoacremonium parasiticum is a dematiaceous fungus first described as a cause of soft tissue infection in a renal transplant patient. Lung nodules have not been previously described and this is the first case, to our knowledge, of P. parasiticum identified after lung transplantation.

Clinical spectrum of gram-positive infections in lung transplantation.

PURPOSE: Gram-positive (GP) organisms are among the most common cause of infections in early postsurgical and immunocompromised populations. Patients recovering from lung transplantation (LT) are particularly susceptible owing to the physiologic stress imposed by surgery and induction with intense immunosuppression. Sites, types, and timing of GP infections following LT are not well documented. This report describes the clinical spectrum of GP infections and their effects on surgical airway complications (SAC) and bronchiolitis obliterans syndrome (BOS) following LT. METHODS AND MATERIALS: Data were collected from 202 patients undergoing 208 LT procedures at a single institution between November 1990 and November 2005. Data were retrospectively analyzed according to timing, location, and causative pathogen. RESULTS: In the median follow-up period of 2.7 years (range, 0-13.6 years), 137 GP infections were confirmed in 72 patients. Sites of infection included respiratory tract (42%), blood (27%), skin, wound and catheter (21%), and other (10%). GP pathogens identified were Staphylococcus species (77%), Enterococcus species (12%), Streptococcus species (6%), Pneumococcus (4%), and Eubacterium lentum (1%). The likelihood of SAC and BOS was increased in lung allograft recipients with GP pneumonia as compared with those without (hazard ratio 2.1; 95% confidence interval=1.5-3.1). CONCLUSIONS: GP organisms were responsible for infections in 40% of lung allograft recipients and most commonly isolated from the respiratory tract and blood stream. Staphylococcal species were most frequently identified, 42% of which were methicillin-resistant Staphylococcus aureus (MRSA). Given the strong association of respiratory tract infections with the development of SAC and BOS, empiric antimicrobial strategies after LT should include agents directed against GP organisms, especially MRSA.

Clostridium difficile colitis in lung transplantation.

PURPOSE: Clostridium difficile colitis (CDC) is the most common nosocomial infection of the gastrointestinal tract in patients with recent antibiotic use or hospitalization. Lung transplant recipients receive aggressive antimicrobial therapy postoperatively for treatment and prophylaxis of respiratory infections. This report describes the epidemiology of CDC in lung recipients from a single center and explores possible associations with bronchiolitis obliterans syndrome (BOS), a surrogate marker of chronic rejection. METHODS: Patients were divided into those with confirmed disease (CDC+) and those without disease (CDC-) based on positive C. difficile toxin assay. Because of a bimodal distribution in the time to develop CDC, the early postoperative CDC+ group was analyzed separately from the late postoperative CDC+ cohort with respect to BOS development. RESULTS: Between 1990 and 2005, 202 consecutive patients underwent 208 lung transplantation procedures. Of these, 15 lung recipients developed 23 episodes of CDC with a median follow-up period of 2.7 years (range, 0-13.6). All patients with confirmed disease had at least 1 of the following 3 risk factors: recent antibiotic use, recent hospitalization, or augmentation of steroid dosage. Of the early CDC+ patients, 100% developed BOS, but only 52% of the late CDC+ patients developed BOS, either preceding or following infection. CONCLUSION: CDC developed in 7.4% of lung transplant patients with identified risk factors, yielding a cumulative incidence of 14.7%. The statistical association of BOS development in early CDC+ patients suggests a relationship between early infections and future chronic lung rejection.

Spine abnormalities and damage in patients cured from Cushing's disease.

The skeletal system is a common target of glucocorticoids. Structural and functional impairment of skeletal system is a relevant cause of morbidity and disability in patients with Cushing's syndrome. Thirty-six patients long-term (3.9 +/- 0.5 yrs) cured from Cushing's disease (CD), 26 with adulthood-onset CD (AOCD) and 10 with childhood-onset CD (COCD) and 2 groups of controls, 24 age- and sex-matched patients with nonfunctioning pituitary adenomas (NFA) and 36 age- and sex-matched healthy subjects (HS), entered this open transversal controlled study to evaluate the prevalence of spine abnormalities and damage by standard radiography in subjects with a history of Cushing's syndrome. Symptoms and signs of backache were present in 86.1% CD patients (100% COCD and 80.8% AOCD), in 30.5% HS (chi2 = 20.6, p < 0.0001) and 37.5% NFA patients (chi2 = 13.2, p < 0.0001). The prevalence of trabecular bone rarefaction (chi2 = 6.5, p < 0.01 and chi2 = 4.5, p < 0.05), vertebral collapse (chi2 = 10.7, p < 0.01 and chi2 = 7.0, p < 0.01) and scoliosis (chi2 = 10.9, p < 0.01 and chi2 = 11.1, p < 0.01) resulted significantly increased in CD patients as compared both to HS and NFA patients. In CD patients, the number of collapsed vertebral bodies was significantly correlated to age of disease onset (r = -0.63, p < 0.0001), disease duration (r = 0.33, p < 0.05) and urinary free cortisol levels at disease diagnosis (r = 0.72, p < 0.0001). The prevalence of cortical bone sclerosis was significantly increased in AOCD than in HS (chi2 = 6.5, p < 0.01) and COCD (chi2 = 7.7, p < 0.01) whereas that of trabecular bone rarefaction was significantly higher in COCD patients than in HS (chi2 = 18.3, p < 0.0001), NFA (chi2 = 14.2, p < 0.0001) and AOCD patients (chi2 = 9.1, p < 0.01). Patients cured from CD have increased prevalence of spine damage, mostly when the disease developed before the completion of skeletal growth. Therefore, a periodical radiological follow-up of the skeleton and a specific treatment for the bone damage should be included in the management of patients with Cushing's syndrome.

[Urinary stress incontinence. Comparison of the Raz technique and the Bologna technique. Analysis of a series of 188 patients]. / Incontinence urinaire d'effort féminine. Comparaison de la technique de Raz et de la technique de Bologna. Analyse d'une série de 188 patientes.

OBJECTIVE: Our purpose was to evaluate and compare the perioperative morbidity and the long-term results of the Raz colposuspension and the Bologna operation for the treatment of stress urinary incontinence in women. STUDY DESIGN: Data of 188 women who underwent either a Bologna operation (group 1) or a Raz colposuspension (group 2) for the treatment of stress urinary incontinence between January 1, 1987 and December 1, 1995 were analysed retrospectively regarding history, preoperative evaluation, associated surgical procedures, complications and cure and failure rate. POPULATION AND METHODS: 80 patients were treated with the Bologna operation and 108 with the Raz colposuspension. Patients with prior anti-incontinence surgery, and patients with a preoperative diagnosis of urge incontinence were excluded from the study. Success was defined both subjectively (complete absence of complaint of stress urinary incontinence) and objectively (no evidence of loss of urine on cough provocation during physical examination). Survival curves were generated in each group for time to event data: "time to recurrent stress incontinence" and compared by the logrank test. A multivariate analysis using a Cox proportional hazards regression model was performed to indentify possible outcome predictors. RESULTS: The success rate of group 1 was significantly higher than that of group 2 (p = 0.00001). The median of success was 51 months in group 1 and 21 months in group 2 (p = 0.00001). The incidence of intraoperative complications in each group (inadvertent cystostomy, hemorrhage) did not differ. The multivariate analyses using the Cox regression model showed that the most highly correlated variable with the surgical cure rate was the type of surgical anti-incontinence procedure adopted: Bologna or Raz (p = 0.00001) CONCLUSION: In our hands, the Bologna operation has a higher cure rate than the Raz colposuspension. For us, when treating patients with stress urinary incontinence by the vaginal route, the Bologna operation is indicated when sufficient anterior vaginal tissue is available to create vaginal bands.

[Postoperative neurosurgical complications in brain tumors operated in the elderly]. / Complicazioni post-operatorie neurochirurgiche in tumori cerebrali operati in età geriatrica.

200 patients of geriatric age, operated on for cerebral neoplasm, have been studied in order to estimate the most important factors influencing the post-operative course. We have considered the "Volume of the tumour", the "Pre-operative and at-discharge Karnofsky Score", the possible "Pre-existent pathologies" and the checked "Post-operative complications". As a conclusion we have considered relevant over the final outcome the following factors: a) the presence of general pre-existent pathologies, first of all diabetes and hypertension; b) the volume, more than the site and nature, of the neoplasm subject of the operation; c) the nature and the importance of local post-operative complications.

[Statistical comparison of surgical results with or without laser in neurosurgery]. / Comparaison statistique des résultats chirurgicaux avec et sans laser en neurochirurgie.

In the literature, no significant statistical studies have been published on the effectiveness of laser compared with traditional procedures in neurosurgery; we have decided to study a series of 198 gliomas and 220 meningiomas operated upon either with a laser or with conventional techniques. We considered the post-operative morbidity, the duration and the quality of survival. These data have been clearly influenced by the type of surgery. On the contrary, no significative difference was observed concerning the survival rate of gliomas whatever their grading. In the laser-group, morbidity and quality of life are improved (36 months follow-up); but the mortality rate (3 years) is equal in both groups. Concerning meningiomas, patients of both groups (with and without laser) were clinically improved during the post-operative period. A significative difference appears only for meningiomas located in functional areas and operated with a laser.

[Common problems for the neurosurgeon and the anesthesiologist in pediatric neurosurgery]. / Problemi comuni del neurochirurgo e dell'anestesista in neurochirurgia pediatrica.

In pediatric neurosurgery the cooperation between neurosurgeon and anaesthesist is very tight. It begins with the clinical evaluation of preoperative conditions (weight, trophism, age, etc.), then continues with the through preparation of the operative position of the little patient and with the control of unfavourable side-effects of some particular positions (intraoperative air embolism in the sitting position, postoperative tension pneumocephalus). At last this cooperation is very important to analyse the vital functions and the neurological picture in the immediate postoperative period.

Multiple post-traumatic spinal meningocele. Case report.

The Authors refer the case of a man who was successfully operated for a meningocele, consisting of two separate sacs in the right iliopsoas muscle. Etiopathogenetic features of the two sacs are discussed.

Bactericidal effects induced by laser irradiation and haematoporphyrin against gram-positive and gram-negative microorganisms.

Laser irradiation of tissues treated in vivo with haematoporphyrin (Hpr) is known to result in a cytocidal effect, reportedly more pronounced in tumour tissues. To ascertain whether this cytocidal phenomenon can occur not only in eukaryotic but also in prokaryotic cells, the authors devised a model system in vitro consisting of bacterial cultures in liquid and in solid media. Bacteria photosensitized with Hpr were subsequently exposed to laser beams and to daylight; then normal microbiological techniques were used to determine whether any bactericidal effect occurred. Satisfactory results were achieved, particularly against Gram-positive microorganisms; a partial inhibition of Gram-negative microorganisms was also observed.

Comparison of four hippurate hydrolysis methods for identification of thermophilic Campylobacter spp.

The test for hippurate hydrolysis is critical for separation of Campylobacter jejuni and C. coli strains. Glycine and benzoic acid are formed when hippurate is hydrolyzed by C. jejuni. The test used in most laboratories is one of several variations of the ninhydrin tube test described by Hwang and Ederer (M. Hwang and G. M. Ederer, J. Clin. Microbiol. 1:114-115, 1975) for detection of glycine. We evaluated three modifications of the Hwang and Ederer method and the gas-liquid chromatographic (GLC) method described by Kodaka et al. (H. Kodaka, G. L. Lombard, and V. R. Dowell, Jr., J. Clin. Microbiol. 16:962-964, 1982) for detecting benzoic acid. Campylobacter strains comprised 22 C. jejuni, 11 C. coli, and 8 C. laridis strains. The species identification of each strain was confirmed by DNA relatedness. All strains of C. jejuni were positive and all strains of C. coli and C. laridis were negative by the GLC method for detecting hippurate hydrolysis, whereas three strains of C. jejuni gave negative or variable results in the tube tests. The GLC method is more sensitive than the tube methods for detecting hippurate hydrolysis and should be used on cultures yielding variable or questionable test results.

Treatment of cerebral arterio-venous malformations with laser.

The surgical application of the laser in the treatment of vascular diseases of the brain is based on its characteristic to perform an immediate or delayed modification of the vessel wall either by shrinking the collagenous fibres or by intraluminal thrombosis. Personal researches have been carried out to study the histological modifications of the vessel wall in normal arteries following laser irradiation with Nd:YAG. On this basis we have treated arterio-venous malformations (AVMs) in man. The laser enables radical surgery with a complete preservation of the healthy tissue surrounding the lesion because of reduced manipulation and the absence of intraoperative haemorrhage. Doppler technique and real-time ultrasonography are mostly suitable in the identification of the small deep-seated AVMs localizing the site of the malformation and the reactive glial tissue surrounding the lesion. The main indications are small AVMs located in critical areas of the brain.

Comparison of three reagents for detecting indole production by anaerobic bacteria in microtest systems.

Three reagents for detecting indole, Kovac, Ehrlich, and p-dimethylaminocinnamaldehyde (DMCA), were evaluated with commercial microtest systems for characterizing and identifying anaerobic bacteria. The DMCA reagent, the most sensitive of the three reagents, gave a positive reaction with 445 of 449 strains of various indole-producing anaerobic bacteria. There was 99.6% agreement between the results obtained with the DMCA in the microtest systems and results using the conventional tube test to detect indole by using xylene extraction and Ehrlich reagent. Ehrlich reagent detected indole in 163 of 176 (92.6%) indole-positive strains when the inoculum was overlaid with mineral oil before incubation. Kovac reagent was the least sensitive of the reagents tested. When the inoculum was overlaid with mineral oil, Kovac reagent detected only 80 of 108 (74.0%) of indole-positive strains. In addition to being the most sensitive reagent for detection indole, DMCA also allowed detection of indole derivatives (skatole, 3-indolepropionic acid, and 3-indolebutyric acid) produced by some clostridia.