Early stages in the self-organization of Si nanopatterns induced by ion bombardment.

We reveal early stages of self-organization of nanopatterns created by 2 keV Cs+ ion-beam irradiation of a Si surface coated with Au and a Ti adhesion layer. After ion-beam etching of the metallic layers, at normal incidence, we first observe distinct transient stages: (I) a dewetting-like pattern of grooves in the Si amorphized layer, sparsely populated with holes, followed by (II) the coexistence of rounded mounds and faceted holes distributed on a flat surface, the latter being an indication of the decisive role played by the crystalline/amorphous interface. Subsequently, the system evolves to stage III, a nanopattern of densely packed nanodots convoluted with a long-wavelength surface corrugation. A momentum-space analysis shows that stages (I) and (II) are identified, respectively, with channel-type and sphere-type quasi order.

Alternative uses of a megavolt tandem accelerator for few-keV studies with ion-source SIMS monitoring.

We increase the versatility of a tandem electrostatic accelerator by implementing simple modifications to the standard operation procedure. While keeping its ability to deliver MeV ion beams, we show that the experimental setup can (i) provide good quality ion beams in the few-keV energy range and (ii) be used to study ion-beam surface modification with simultaneous secondary ion mass spectrometry. This latter task is accomplished without using any chamber connected to the accelerator exit. We perform mass spectrometry of the few-keV anions produced in the ion source by measuring their neutral counterparts at the accelerator exit with energies up to 1.7 MeV. With an additional modification, a high-current few-keV regime is obtained, using the ion source as an irradiation chamber and the accelerator itself only as a mass spectrometer. As an example of application, we prepare a sample for the study of ion-beam assisted dewetting of a thin Au film on a Si substrate.

Frontiers of robotic endoscopic capsules: a review.

Digestive diseases are a major burden for society and healthcare systems, and with an aging population, the importance of their effective management will become critical. Healthcare systems worldwide already struggle to insure quality and affordability of healthcare delivery and this will be a significant challenge in the midterm future. Wireless capsule endoscopy (WCE), introduced in 2000 by Given Imaging Ltd., is an example of disruptive technology and represents an attractive alternative to traditional diagnostic techniques. WCE overcomes conventional endoscopy enabling inspection of the digestive system without discomfort or the need for sedation. Thus, it has the advantage of encouraging patients to undergo gastrointestinal (GI) tract examinations and of facilitating mass screening programmes. With the integration of further capabilities based on microrobotics, e.g. active locomotion and embedded therapeutic modules, WCE could become the key-technology for GI diagnosis and treatment. This review presents a research update on WCE and describes the state-of-the-art of current endoscopic devices with a focus on research-oriented robotic capsule endoscopes enabled by microsystem technologies. The article also presents a visionary perspective on WCE potential for screening, diagnostic and therapeutic endoscopic procedures.

An electromyographic study of the vastii muscles during open and closed kinetic chain submaximal isometric exercises.

BACKGROUND: Rehabilitation programs for patients with patellofemoral dysfunction aim to recruit the vastus medialis obliquus muscle (VMO) in an attempt to reduce pain and to improve patellar tracking. OBJECTIVES: The aim of the present study was to use surface EMG to assess the effectiveness of two isometric submaximal contractions (10% and 60% of maximal voluntary contraction, MVC) in promoting preferential activation of VMO over vastus medialis longus (VML) and vastus lateralis (VL) in open and closed kinetic chain isometric exercises with the knee joint fixed at 30, 60 and 90 degrees of flexion. METHODS AND MEASURES: Surface electromyography (EMG) signals were recorded with linear adhesive arrays of four electrodes from fourteen healthy young men (age 23.5±3.2, mean±SD) during isometric knee extension contractions at 10% and 60% of the maximum voluntary contraction (MVC) for 1 min and 20 s respectively at 30, 60 and 90 degrees of knee flexion. Initial values and rate of change (slope) of mean frequency (MNF), average rectified value (ARV) and conduction velocity (CV) of the EMG signal were calculated. RESULTS: Comparisons between the force levels produced at 10% and 60% MVC revealed that the initial values of ARV and CV for the VL, VML and VMO muscle were greater at 60% MVC compared to 10% MVC (3-way ANOVA; F=536; p<0.001, F=49: p<0.01 for ARV and CV respectively). Comparisons between the different muscles demonstrated lower initial values of CV for VMO compared to VL and VLM at 10% and 60% of MVC (F=15; p<0.05). In addition, initial estimates of ARV were higher for VMO compared to VML at both force levels (F=66; p<0.05). Comparisons between open and closed kinetic chain exercises revealed higher initial estimates of ARV for open kinetic chain knee extension at both force levels (F=62; p<0.01). In addition, the absolute value of MNF slope appeared to increase at higher angles for closed kinetic chain at 60% MVC while it was minimum at 60° degrees for open kinetic chain. No significant differences were observed in the rate of change of CV and MNF among the three muscles. CONCLUSIONS: Based on the results of this study, both open and closed kinetic chain exercise similarly activate the three portions of the quadriceps muscle, suggesting that selective training of the vastii muscle is not achievable in these conditions.

Serum free light-chain responses after high-dose intravenous melphalan and autologous stem cell transplantation for AL (primary) amyloidosis.

Serum free light-chain (FLC) concentrations were measured by a sensitive nephelometric immunoassay in 66 patients with AL amyloidosis before and after treatment with high-dose melphalan and autologous stem cell transplantation (HDM/SCT). At 1 year after HDM/SCT, 27 patients (41%) achieved a complete hematologic response (CR), that is, disappearance of the monoclonal gammopathy previously evident by immunofixation electrophoresis (IFE) in serum and urine and of plasma cell clonality in the bone marrow. Abnormally elevated FLC levels became normal in 27 patients (41%), and decreased by >90% in 37 (56%). Average improvements in FLC were 94% for patients who achieved a CR and 72% for those who did not (P=0.0001). However, a reduction in FLC of >90% was associated with a similar high likelihood of clinical improvement and prolonged survival, whether or not patients achieved a CR. While CR, as defined by standard criteria, is a more stringent indicator of hematologic response than are decreases in abnormally elevated FLC levels per se, these measures of hematologic response are complementary, and decreases in FLC are more readily detected early after treatment than are the changes in IFE and marrow studies required to determine CR.

Minimally invasive thoracic surgery for diagnostic assessment and palliative treatment in recurrent neoplastic pleural effusion.

BACKGROUND: We evaluated the effectiveness of VATS in the diagnosis and palliative treatment of recurrent neoplastic pleural effusions. METHODS: From 1987 to 2001, we performed 325 VATS chemical pleurodesis for malignant pleural effusions. We used talc in 253 subjects (78 %) and alcohol in 72 (22 %) as the sclerosant agent. In 226 patients (68 %) we performed biopsies because the histology was unknown. RESULTS: Mean operating time was 33.38 +/- 9.77 minutes (median: 32; range: 19 - 58), and the mean duration of chest intubation was 3.78 +/- 1.33 days (median: 4; range 2 - 8). Complications occurred in 2 % of patients. Thirty-day mortality was 2 %. Mean postoperative in hospital stay was 5.53 +/- 1.90 days (median 6; range: 2 - 11). We obtained 264 (81 %) therapeutic successes (no effusion recurrence within 4 months), and 55 relapses of which 32 had talc insufflation (13 % of talc group) and 23 alcohol instillation (32 % of alcohol group). CONCLUSIONS: VATS chemical pleurodesis is a safe, useful, versatile procedure for oncological pleural effusion management. The use of talc rather than alcohol significantly increased the therapeutic success rate. VATS should be considered the treatment of choice in patients with advanced neoplasm to obtain good palliation and a better quality of life.

[Use of the skin-closure system Medizip in median sternotomy in oncological patients. Evaluation of results obtained in 30 patients]. / Utilizzo del dispositivo Medizip per la sutura cutanea in caso di sternotomia mediana in pazienti oncologici. Valutazione dei risultati ottenuti in 30 pazienti.

BACKGROUND: The authors evaluate effectiveness, safety and cosmetic results obtained using the new skin closing system Medizip. METHODS: At the Thoracic Surgery Department of the National Cancer Institute (Milan) between June 1999 and March 2001, in 30 patients who underwent median sternotomy for bilateral pulmonary wedge resections, Medizip a new skin-closing system to suture the sternal wounds has been used. Twenty patients were under 30 (66%) and 6 of the 10 remaining were females. The average age was 34.25+/-21.60 years, (median: 25, range: 12-72). It took about half a minute (average time: 30.00+/-10.54 seconds) to perform all the application manoeuvres. In order to better evaluate the cosmetic results obtained, a scale of three levels was created: level 1: very good, level 2: satisfactory, level 3: inadequate. RESULTS: Twenty-eight 20 cm-long zippers, one 25 cm-long and one 30 cm-long were employed. Medizip has been kept in site for 9.88+/-2.12 days on average (median: 9; range: 8-12). The time employed for each dressing was on average 70.00+/-21.35 seconds (median: 70, range: 46-128). No wound infections were observed even if all the patients were affected by neoplastic diseases and were immunocompromised because of lots of antiblastic treatments. The quick removal (few seconds) and the non-invasiveness of the disposal constitutes remarkable advantages. Using the criteria previously described, 26 patients at level 1 (87%), and 4 (13%) at level 2 were classified. CONCLUSIONS: Medizip is considered to be an effective skin-closure system easy and quick to handle, assuring very good cosmetic results, with non-invasive removal, particularly useful in pediatric patients and in young adults affected by neoplastic diseases undergone to a lot of combined treatments.

A particular case with long-term follow-up of rare malignant hemangiopericytoma of the lung with metachronous diaphragmatic metastasis.

The authors report the case of a woman with a primary hemangiopericytoma of the lung and successive metachronous diaphragmatic metastasis treated with surgery only according to the patient's decision. The patient was first submitted to left lower lobectomy with resection of diaphragm and three ribs en-bloc for pulmonary sarcoma. One year later, a chest computed tomography (CT) scan showed a small lesion above the diaphragm on the left side. She refused the proposed operation and returned fifteen months later with a new thorax CT, and told us that she had in the meantime become pregnant and given birth. A rethoracotomy to remove the metastatic diaphragmatic tumor was performed. Chemotherapy with anthracycline and iphosphamide was proposed, but the patient again refused therapy for fear of side effects impairing another pregnancy. Currently, the patient is alive and disease-free, 68 months after the first treatment. The authors emphasize the long-term follow-up obtained with surgery alone in this kind of rare sarcoma.

Major surgery in lung cancer in elderly patients? Risk factors analysis and long-term results.

BACKGROUND: In the Oncological Thoracic Surgery Department of the Istituto Nazionale Tumori of Milan a retrospective study was performed on lung cancer patients 70 years old or more with the aim of evaluate the role of surgical treatment and to analyse long-term results. METHODS: In our Institute from January 1988 to December 1993, 151 lung cancer patients 70 years old or more underwent surgery for lung cancer. One hundred and twenty-six of them (83%) were males and 25 were females (17%), the average age was 73.09+/-2.91 years (median: 77; range: 70-82). All the subjects were completely staged preoperatively. In order to establish operability criteria, we considered some selection parameters. Patients general conditions were evaluated using Karnofsky score accepting only the ones with 70% or more for surgery, all the cases performed cardio-respiratory functional evaluation. Patients with: a) FEV1 <60% of predicted value or FEV1 <1 l; b) PaO2 <60 mmHg e PaCO2 >40 mmHg were excluded from surgery. RESULTS: The operations performed were: 23 pneumonectomies, 6 bilobectomies, 93 lobectomies, 13 segmentectomies and 16 wedge resections. Eight cases were submitted to thoracectomy in association to pulmonary resection. Peroperative mortality was 3% and morbidity was 10%. Histological examination showed 69 adenocarcinomas, 65 squamous carcinomas, 4 large cells carcinomas, 4 typical carcinoids, 5 small cells carcinomas, 2 mucoepidermal carcinomas and 2 adenosquamous carcinomas. Eighty-six patients were classified at stage I, 38 at stage II, 24 at stage III and 3 at stage IV (multifocal disease). The actuarial 4-years global survival predicted with Kaplan Meier method was 40%, in particular it was 75% for stage I patients. CONCLUSIONS: In case of resectable primary pulmonary neoplasm, surgery represents the first choice therapy; patient's age doesn't seem to be an absolute contraindication, but it has to be evaluated with biological and not with age criteria. Using adequate selection criteria, it's possible to obtain, in patients older than 70 years, long-term survivals that don't seem to differ from global survivals.