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The residential sector is characterized by new digital challenges. The Internet of Things (IoT) is a key-driver of innovation and operations management. This study aims to measure and assess IoT devices at the level of individuals, which are households, in European countries. For this scope, through the multi-criteria decision analysis (MCDA), we analyse data from Eurostat providing a mix of indicators allowing information to be aggregated at the level of individual Europeans and disaggregated by age group. The results highlight that only four countries (Netherlands, Denmark, Sweden and Malta) are classified as a high cluster in the examined scenarios. The 16–24 age group is the most involved in the uses of IoT devices, but the previous three northern European countries also show very high values for the 35–44 age group. IoT devices serve as a springboard for achieving a powerful propulsion toward technological innovation in the new business models, identifying opportunities and being a way to make many routine tasks more agile. Training programs and awareness campaigns are policy suggestions for the development of IoT devices favouring a cultural change on their use. However, there is an emerging need for studies that monitor environmental health impacts to prevent possible threats.

Congenital pseudoarthrosis of the tibia (CPT) is a rare disease characterised by the onset of bone anomalies or fractures, leading to deformities in paediatric patients. The aetiology of this pathology is unknown. The main theories include the presence of hamartomatous tissue related to Neurofibromatosis type 1, vascularisation deficit of the periosteum and alterations in the numbers and functions of the osteoblasts and osteoclasts in loco. Surgical treatment generally requires multiple operations during the patient's childhood and adolescence. The best outcomes seem to occur when using intramedullary nailing, vascularised fibular transplant and external fixation with the Ilizarov technique. The purpose of this paper is to evaluate the effectiveness of in-situ injections of Bone Marrow Aspirate Concentrate (BMAC) as an adjuvant therapy for congenital pseudoarthrosis of the tibia in patients treated with external fixation and that of radiographic healing over time compared to external fixation treatment alone. We performed a retrospective review of clinical and radiographic records of patients affected by CPT and treated in the Paediatric Orthopaedics and Traumatology Department of the Gaetano Pini Orthopaedic Institute with in-situ injections of bone marrow aspirate concentrate (BMAC) on the pseudoarthrosis site, in addition to pseudoarthrosis site excision and application of circular external fixator frame in compression (Group A). The time needed to reach the radiological consolidation of the resection site was recorded and compared to that needed for patients treated with only pseudoarthrosis site excision and application of circular external fixator frame in compression (Group B). There is a statistically relevant improvement of healing time in patients affected by congenital pseudoarthrosis of the tibia treated with external fixation and bone marrow aspirate concentrate compared to patients affected by the same pathology treated with external fixation only. Injection of MSC in the pseudoarthrosis site after focus removal in combination with circular external fixation achieves faster bone healing compared with external fixation only, and the lower refracture percentage may be associated with the better quality and structure of the new bone. However, it would be desirable to have a longer followup to determine if the results of the BMC as adjuvant therapy will hold up over time.

The aim of the present study was to evaluate the impact of the aortic bifurcation (AB) morphological characteristics, analyzed on computed tomography angiography (CTA), on outcomes of patients with abdominal aortic aneurysms (AAAs), treated by endovascular aneurysm repair (EVAR) in a single-center experience. A retrospective analysis was conducted using a prospectively collected database. Morphological features considered as potentially impacting outcomes were maximum AB diameter (ABmax), minimum diameter (ABmin), mean diameter (ABaverage), AB area (ABarea), and AB calcification (ABcalcification) and thrombosis (ABthrombosis). Outcome measures were perioperative, 30-day, and midterm AAA-related reinterventions and all-cause mortalities. Investigators reviewed 306 preoperative CTA scans. Maximum aortic diameter was 51.4 ± 12.4 mm (range 40–110), and mean ABmax was 24.2 ± 8.8 mm (range 10–60), ABmin 17.0 ± 5.4 mm (range 4–40), ABaverage 20.6 ± 6.5 mm (range 9–47.5), and ABarea 35.2 ± 24.2 mm2 (range 6–176). ABcalcification ≥ 50% was present in 63 patients (20.6%), and ABthrombosis ≥ 50% in 102 patients (33.3%). Technical success was obtained in all cases, without perioperative reintervention or death. At 30-day follow-up, the reintervention rate was 3.3%, and mortality rate was 1.3%. At a mean follow-up period of 35 ± 28.6 (range, 1–72) months, reintervention and mortality rates were 6.5 and 4.9%, respectively. None of the analyzed thresholds were predictive of adverse outcomes. At multivariate analysis, association of a narrowed AB with severe calcification of the distal aorta showed a significant differences in terms of reinterventions (p = 0.009). Our limited experience seems to reveal that a cutoff of ≤ 20 mm for AB diameter, as in current guidelines, is ineffective in predicting outcomes after EVAR.

Il presente studio ha avuto come obiettivo la valutazione dei cambiamenti, durante l’arco dei quattro anni di formazione, di un gruppo di 20 allievi di una scuola di specializzazione in psicoterapia di orientamento cognitivo. I dati del gruppo sperimentale sono stati confrontati con quelli di un gruppo di controllo. Entrambi i gruppi hanno redatto, all’inizio e al termine della formazione, un’autocaratterizzazione, strumento che permette di comprendere la prospettiva con la quale un individuo costruisce la propria realta con modalita di cambiamento in continuo divenire. Alle autocaratterizzazioni e stata applicata l’analisi del contenuto, definita da Berelson come capace di descrivere in modo obiettivo, sistematico e quantitativo il contenuto manifesto della comunicazione. E stato adottato un protocollo che ha definito le procedure seguite, il manuale dei codici interpretativi e la griglia di codifica. Ogni autocaratterizzazione e stata analizzata da un gruppo di analisti con meccanismi di controllo delle decodifiche soggettive. Per verificare se ai soggetti siano accaduti, nell’arco temporale preso in considerazione, eventi che possano aver inciso sull’assetto cognitivo e stato somministrato il Questionario sugli Avvenimenti della Vita (QAV).I risultati della ricerca attestano variazioni significative tra gruppo sperimentale e gruppo di controllo. Gli allievi, dopo quattro anni di formazione, ritengono che gli altri riconoscano in loro una maggiore capacita di spiegare comportamenti e atteggiamenti degli altri, una maggiore capacita autoriflessiva, un senso di soddisfazione per il completamento del proprio percorso formativo e quindi l’assunzione di un ruolo professionale.

We reported the case of a 38-year-old patient who in 2017 presented to our institution after post-traumatic complete ankylosis of the elbow. He complained of stiffness and pain, and the radiographs revealed complete fusion of the humeroulnar joint. The Mayo Elbow Performance Score (MEPS) on admission was 31, and the elbow was fused at 90° flexed position. The patient underwent semiconstrained total elbow arthroplasty with Bryan-Morrey approach; after a 2.1 years follow-up, active arc of movement was 120°. The MEPS was excellent with a 100 points score, the patient was able to complete all activities of daily living. We did not report any complications. Total elbow arthroplasty has shown to be a good therapeutic option that make it possible to restore adequate functional range of motion and relieve pain in young patients with post-traumatic stiffness/arthritis of the elbow.

This volume explores the issues of using e-learning in university and of developing and using a “blended learning” teaching method for the course of Computer Science from the first year of the the Medicine and Surgery Degree of the University of Florence. This course was used as a trial for the peer-review teaching method, which can be useful in classes with a high number of students; this publication also includes a selection of the best works produced by the students. The results of the trial prove the advantages of using the peer-review teaching method for other university courses, and the students' works on e-health give current medical practitioners insights on how to use ICT in their practice with skill and care.Nel volume si affrontano i temi dell’e-learning nella formazione universitaria e della progettazione ed erogazione in modalita blended learning dell’insegnamento di Informatica del I anno del Corso di Laurea in Medicina e Chirurgia dell’Universita di Firenze. In tale insegnamento e stata sperimentata la metodologia didattica di revisione tra pari, utile in classi ad elevata numerosita; l’opera raccoglie inoltre una selezione dei migliori elaborati prodotti dagli studenti. I risultati ottenuti dimostrano l’utilita di esportare ad altri insegnamenti universitari la metodologia didattica della revisione tra pari e gli elaborati degli studenti inerenti l’e-health permette ai medici in attivita di aggiungere conoscenze per utilizzare con perizia e consapevolezza le ICT nell’esercizio della professione.

The paper presents the evaluation plan and the first results of DIDeL (Didactics in e-Learning), a research and development project of the University of Florence, aimed at promoting faculty professional development on e-learning methods and technologies. From a theoretical point of view the project is based on a multi-levels model characterized by the combination of methodological approaches and teaching tools. The evaluation plan reflects this articulation with the aim to measure users' satisfaction, the impact of the programme on teachers' techno-didactic competences on the short and medium run, as well as the impact on students' career progression. Specifically, this papers illustrates and discusses the results of a questionnaire administered online to all the teachers who participated in at least one of the project's training activities during the first half of 2018: it was investigated the level of satisfaction of training and teachers' self-perception of learning in terms of knowledge and skills. 166 teachers answered the questionnaire. The results show a high level of appreciation for the various types of training initiatives, which confirms the design hypotheses and the methodologies adopted.

Acute limb ischemia (ALI) is a pathological condition resulting from a sudden blood interruption (or, at least, from an important reduction in flow) limiting tissues’ survival. ALI is always a serious event requiring immediate diagnosis and treatment, also considering the high associated amputation risk. The most frequent causes of acute limb ischemia are embolism, thrombosis, and trauma. Clinical findings are grouped together in a series mnemonic note as “6P of Pratt”: pain, pallor, pulselessness, poikilothermia, paresthesia, and paralysis. Those in concert with duplex ultrasound assume a primary and crucial role in diagnostic and preoperative evaluation of ALI patients. Treatment for ALI largely depends on the clinical presentation according to Rutherford’s classification. When indication for surgery is posed, several open, endovascular, and hybrid procedures are developed to restore blood flow in acute patients.

To report a case of pararenal aortic aneurysm (PAAA) with narrowed iliac arteries treated by the chimney technique combined with the INCRAFT

In this work we consider an inverse ill-posed problem coming from the area of dynamic magnetic resonance imaging (MRI), where high resolution images must be reconstructed from incomplete data sets collected in the Fourier domain. The reduced-encoding imaging by generalized-series reconstruction (RIGR) method used leads to ill-conditioned linear systems with Hermitian Toeplitz matrix and noisy right-hand side. We analyze the behavior of some regularization methods such as the truncated singular value decomposition (TSVD), the Lavrent'yev regularization method and conjugate gradients (CG) type iterative methods. For what concerns the choice of the regularization parameter, we use some known methods and we propose new heuristic criteria for iterative regularization methods. The simulations are carried on test problems obtained from real data acquired on a 1.5 T Phillips system. © 2002 Elsevier Science Inc. All rights reserved.

Purpose: Hypogastric artery (HA) revascularization during endovascular aneurysm repair (EVAR) is still open to debate. Moreover, exclusion-related complication rates reported in literature are not negligible. The aim of this study is to present and analyze the outcomes in patients undergoing EVAR with exclusion of 1 or both HAs at our academic center. Methods: We retrospectively reviewed our results in patients submitted to EVAR and needing HA exclusion, in terms of perioperative (30-day) and follow-up rates of intestinal and spinal cord ischemia, buttock claudication, buttock skin necrosis, and sexual dysfunction. Results: From January 2008 to December 2014, a total of 527 patients underwent elective standard infrarenal EVAR; among those 104 (19.7%) had iliac involvement needing HA exclusion. In 73 patients with unilateral iliac involvement (70.1%, group UH), many single HAs were excluded. Thirty-one patients (29.9%) had bilateral iliac involvement (group BH), of which 16 (51.6%) had 1 HA excluded with revascularization of the contralateral one (group BHR); in the remaining 15 patients (48.4%) both HAs were excluded (group BHE). No 30-day or follow-up aneurysm-related mortality, intestinal, or spinal cord ischemia were recorded. At 30 days, skin necrosis was observed in 2 patients. Buttock claudication and sexual dysfunction rates were significantly greater in group BHE than in group BHR ( P < .05). At a mean 18.6 months follow-up (range: 4-47), buttock claudication and sexual dysfunction rates in group BHE were persistently higher than that in groups UH and BHR ( P < .05); HA coil embolization was significantly associated with buttock claudication and sexual dysfunction ( P < .05). Conclusions: Whenever anatomically feasible, at least 1 HA should be salvaged in case of bilateral involvement. In case of unilateral HA exclusion, the rate of complications is not negligible. Coil embolization is related to a higher complication rate.

The aim of the present study was to evaluate the reciprocal relationships between motor impairment, dopaminergic dysfunction, and cerebral metabolism (rCMRglc) in de novo Parkinson's disease (PD) patients.Twenty-six de novo untreated PD patients were scanned with (123)I-FP-CIT SPECT and (18)F-FDG PET. The dopaminergic impairment was measured with putaminal (123)I-FP-CIT binding potential (BP), estimated with two different techniques: an iterative reconstruction algorithm (BP(OSEM)) and the least-squares (LS) method (BP(LS)). Statistical parametric mapping (SPM) multiple regression analyses were performed to determine the specific brain regions in which UPDRS III scores and putaminal BP values correlated with rCMRglc.The SPM results showed a negative correlation between UPDRS III and rCMRglc in premotor cortex, and a positive correlation between BP(OSEM) and rCMRglc in premotor and dorsolateral prefrontal cortex, not surviving at multiple comparison correction. Instead, there was a positive significant correlation between putaminal BP(LS) and rCMRglc in premotor, dorsolateral prefrontal, anterior prefrontal, and orbitofrontal cortex (p0.05, corrected for multiple comparison).Putaminal BP(LS) is an efficient parameter for exploring the correlations between PD severity and rCMRglc cortical changes. The correlation between dopaminergic degeneration and rCMRglc in several prefrontal regions likely represents the cortical functional correlate of the dysfunction in the motor basal ganglia-cortical circuit in PD. This finding suggests focusing on the metabolic course of these areas to follow PD progression and to analyze treatment effects.

In this study we evaluated a further refinement of the background subtraction technique and the introduction of correction factors for the influences produced by kidney depth and surface dimensions on the system counting efficiency

Multihole collimators are the most important piece of instrumentation in determining the tradeoff between spatial resolution and noise in nuclear medicine images. Recently, we found that the collimator-to-detector gap greatly influences the hole-pattern artifacts. In addition, we also showed that specific values of the gap exist which minimize the artifacts: here we call this phenomenon "penumbral masking" (PM). In this paper, we study the matter in greater detail and we take PM into account in the problematic context of designing high-energy collimators by, basically, substituting the conventional hole-array pattern constraint with a mathematical expression of the PM effect. With this approach we found that a solution to the problem of maximizing sensitivity for a given spatial resolution always exists while, without the PM concept, in the case of lead (Pb), a solution exists below 300 KeV, a suboptimal solution can be found within the 300-320 KeV range and no solution at all exists beyond 320 KeV. Thus, one is able to minimize the hole-pattern artifacts while designing high -energy collimators even if a somewhat lower sensitivity has to be accepted: for example, with lead, at 511 KeV, sensitivity is reduced by 20% compared to what it would be without the introduction of PM. When high energies are involved, even with our approach the weight constraint is a major problem, but this does not affect the capability of reducing the hole-pattern artifacts. However, even when the theoretical solution may not be feasible, this approach clarifies the design of high-energy collimators.

To report a case of pararenal aortic aneurysm (PAAA) with narrowed iliac arteries treated by the chimney technique combined with the INCRAFT® AAA stent graft system. A 75-year-old man was diagnosed with a 55-mm PAAA. Patient was judged unfit for open repair and for standard endovascular aneurysm repair (EVAR) due to its clinical and anatomical requirements. Custom-made fenestrated device (FEVAR) was excluded due to the presence of narrowed and heavily calcified iliac axes. Consequently, patient underwent auspicious endovascular aneurysm repair with the INCRAFT System and chimney grafts in the superior mesenteric artery and both renal arteries. At 12 months' follow-up, patient was in good clinical condition, with preserved renal function. Computed tomographic angiography revealed inceptive shrinkage of the aneurysm with patency of aortic and visceral grafts even in the presence of a low-flow type Ia endoleak. Chimney grafts (CGs) combined with the low-profile INCRAFT System seem to be feasible for treating PAAA, in high-risk patients unfit for standard EVAR or FEVAR devices.

The problem of performing an efficient compensation of collimator blur in the three-dimensional (3D) reconstruction of SPECT data acquired in parallel beam geometry is tackled. An approximate model for data acquisition is developed, which leads to the construction of the corresponding projector-backprojector pair. In order to perform some numerical tests, the model is customized to a state-of-the-art neuro-SPECT scanner, which is supplied with a three-segmented parallel beam collimator. Some reconstruction algorithms based on this customization are presented and their results are compared, in terms of quality and timing requirements, with the outcome generated by the corresponding fully 3D model. According to this numerical simulation, where voxel-driven (back-)projectors are used, the conclusion can be drawn that the approximate model produces reconstructions as good as the ones generated by the fully 3D model in a time which is one order of magnitude shorter. In the case that (back-)projectors based on the rotation of the emission matrix are used, the proposed approximate model is evaluated to be about four times faster than the corresponding fully 3D model.

Metastatic involvement of the extrahepatic digestive system is rare. We here report the case of a 62-year-old woman who presented with a bowel obstruction related to a metastasis of breast cancer occurring 12 years after a mastectomy for lobular carcinoma. No other distant metastases were detected except for two nodules of 20 and 5 mm on the right chest wall. Biopsy of the larger nodule showed a lobular carcinoma. The patient underwent a right hemicolectomy and then received chemotherapy combined with letrozole, resulting in a partial response. The literature revealed only a few cases of breast cancer metastatic to the colon. Patients with known breast cancer, particularly of the lobular histological type, who present with specific or less specific abdominal symptoms or signs such a microcytic anemia, should be endoscopically explored in order to detect possible metastases of the primary breast tumor.

A complete theory of camera multihole collimators is presented. The geometrical system response is determined in closed form in frequency space. This closed form accounts for the known efficiency and resolution formulae for parallel beam, fan beam, cone beam and astigmatic collimators as well as for the most frequent hole array patterns and hole shapes. The point spread function in the space domain for a certain collimator and source position can be calculated via a discrete fast Fourier transform. Beside the complete theoretical definition of the response of multihole collimators, this theory allows the definition of accurate models of the geometrical response for SPECT reconstruction and it is suitable for designing new collimators.

In the last decades, diagnosing medical images has heavily relied on digital imaging. As a consequence, huge amounts of data produced by modern medical instruments need to be processed, organized, and visualized in a suitable response time. Many efforts have been devoted to the development of digital Picture Archiving and Communications Systems (PACS) which archive and distribute image information across a hospital and provide Web access to avoid the expensive deployment of a large number of such systems. On the other hand, this approach does not solve problems related to the increasing demand of high performance computing and storage facilities, which cannot be placed within a hospital. In this work we describe MedIGrid, an application that enables nuclear doctors to transparently use high performance computers and storage systems for the PET/SPECT (Positron Emission Tomography/Single Photon Emission Computed Tomography) image processing, management, visualization and analysis. MedIGrid is the result of the joint efforts of a group of researchers committed to the development of a distributed application to test and deploy new reconstruction methods in clinical environments. The outcomes of this work include a set of platform independent software tools to read medical images, control the execution of computing intensive tomographic algorithms, and explore the reconstructed tomographic volumes. In the paper we describe how the collaboration among different research groups has contributed to the integration of the application into a single framework. The results of our work are discussed.

Data from Single Photon Emission Computed Tomography (SPECT) studies are blurred by inevitable physical phenomena occurring during data acquisition. These errors may be compensated by means of reconstruction algorithms which take into account accurate physical models of the data acquisition procedure. Unfortunately, this approach involves high memory requirements as well as a high computational burden which cannot be afforded by the computer systems of SPECT acquisition devices. In this work the possibility of accessing High Performance Computing and Networking (HPCN) resources through a World Wide Web interface for the advanced reconstruction of SPECT data in a clinical environment was investigated. An iterative algorithm with an accurate model of the variable system response was ported on the Multiple Instruction Multiple Data (MIMD) parallel architecture of a Cray T3D massively parallel computer. The system was accessible even from low cost PC-based workstations through standard TCP/IP networking. A speedup factor of 148 was predicted by the benchmarks run on the Cray T3D. A complete brain study of 30 (64×64) slices was reconstructed from a set of 90 (64×64) projections with ten iterations of the conjugate gradients algorithm in 9 s which corresponds to an actual speed-up factor of 135. The technique was extended to a more accurate 3D modeling of the system response for a true 3D reconstruction of SPECT data; the reconstruction time of the same data set with this more accurate model was 5 min. This work demonstrates the possibility of exploiting remote HPCN resources from hospital sites by means of low cost workstations using standard communication protocols and an user-friendly WWW interface without particular problems for routine use.

BACKGROUND Histologic grade of differentiation is a strong prognostic factor for prostate carcinoma. However, most tumors fall in the intermediate group. Nuclear and nucleolar morphometry and analysis of the argyrophilic nucleolar organizer regions (AgNORs) were performed to improve prognosis, especially for patients with intermediate histologic grade tumors. METHODS Core needle biopsies from 65 patients with primary prostate carcinoma at diagnosis were studied. Patients received only hormone therapy. Formalin fixed and paraffin embedded sections were stained with the method of Ploton. The mean AgNOR count was calculated in 100 tumor cells for each case. Nuclear and nucleolar areas from 100 cells were measured with an automated image analyzer. One-way analysis of variance and uni- and multivariate survival analyses were used for statistical evaluation. RESULTS In the whole series, World Health Organization (WHO) tumor grade, nuclear and nucleolar areas, and AgNOR counts were correlated with survival time. By multivariate analysis, only AgNOR counts retained independent prognostic significance. In WHO Grade 2 carcinoma, the 5-year survival rate for patients with AgNOR/cell ≤ 7.84 was 77%, but was only 12% for those with higher counts (P < 0.0001). These survival rates were similar to those obtained when patients with WHO Grade 1 carcinoma and Grade 2 carcinoma plus low AgNOR counts were compared with patients with Grade 3 carcinoma and Grade 2 carcinoma plus high AgNOR counts. In Gleason intermediate Grade 6 and 7 carcinomas, the 5-year survival rate for patients with AgNOR/cell ≤ 7.84 was 71%, but was only 7% for those having higher counts (P = 0.0001). CONCLUSIONS Nuclear and nucleolar areas, as well as AgNOR counts, supplement histologic grading in the prognostic assessment of prostate carcinoma in patients receiving only hormone therapy. AgNOR count also is a prognostic factor for patients with intermediate grade tumors. The combination of histologic grade and proliferative activity allows the stratification of patients into low and high risk groups. Cancer 1997; 79:1956-63. © 1997 American Cancer Society.

This study aimed to identify risk factors for squamous intraepithelial lesions (SIL) in women with known HIV status and to explore the association between SIL, HPV subtype, and HIV-induced immunosuppression. The study population consisted of women with known HIV serological status who were attending a network of 16 clinical centres in Italy. Detailed behavioural data, clinical and laboratory parameters, and samples for diagnosis of SIL by Papanicolau smear and HPV infection using a polymerase chain reaction (PCR) were obtained from each study participant. The strength of the association between SIL and possible risk factors was assessed calculating crude and adjusted odds ratios derived from univariate analysis and multivariate models. We enrolled 236 women, of whom 135 (57.2%) were HIV-infected. SIL was diagnosed in 57 women (24.1%); of these, 48 (35.6%) were HIV-infected and 9 (8.9%) were HIV-negative. HPV-DNA was detected in 41 (72%) women with SIL and in 45 (25%) women without SIL. HPV-DNA was more often detected among HIV-infected women than among HIV-negative women (40% vs. 32%), but the difference was not statistically significant. Women infected with high-risk types or with low-risk-uncharacterised types of HPV both had a higher risk of SIL compared with HPV-negative women (respectively, AOR: 17.53 and AOR: 2.89). HIV-infected women with severe or moderate immunosuppression were more likely to have SIL than HIV-negative women (respectively, AOR: 7.29 and AOR: 3.09) also independently from HPV infection. Women reporting use of a contraceptive pill had a 2.5 times higher risk of SIL compared with those who never used hormonal contraceptives. The results confirm that high-risk HPV types are strongly associated with SIL, and that HIV infection may strengthen the effect of HPV at cervical level. The use of oral contraceptives may slightly increase the risk of SIL in women with at-risk behaviour for HIV infection.

Protein engineering and site-directed mutagenesis is becoming immensely important in both fundamental studies and commercial applications involving proteins and enzymes in biocatalysis. Protein engineering has become a powerful tool to help biochemists and molecular enzymologists elucidate structure-function relationships in enzymic active sites, to understand the intricacies of protein folding and denaturation, and to alter the selectivity of enzymatic catalysis. Commercial applications of engineered enzymes are being developed to increase protein stability, widen or narrow substrate specificity, and to develop novel approaches for use of enzymes in organic synthesis, drug design, and clinical applications. In addition to protein engineering, novel expression systems have been designed to prepare large quantities of genetically engineered proteins. Recent US patents and scientific literature on protein engineering, site-directed mutagenesis, and protein expression systems related to protein engineering are surveyed. Patent abstracts are summarized individually and a list of literature references are given.

The prognostic significance of the argyrophilic nucleolar organizer regions (AgNORs) in tumour pathology is still a matter of debate. A prospective study was performed in a series of renal cell carcinomas to clarify the prognostic value of AgNOR counting. Sections from 21 renal cell carcinomas were stained in 1990 with the method of Ploton. Black dots within the nucleus from 200 tumour cells were counted: the mean AgNOR count for the whole series was 6.13, the median 5.94 and the SD 1.78. Patients were then followed up for at least 6 years or to death: at the time of the survival analysis (June 1996), 13 patients were alive without evidence of recurrence or metastasis, 6 had died of the disease and 2 of myocardial infarction. All the patients with 5.94 AgNORs per cell or fewer were alive at 6-year follow-up, while only 60% of patients with more than 5.94 AgNORs per cell survived (p=0.01). In the multivariate analysis, only AgNOR count (p=0.015) retained an independent prognostic significance. With the limitation due to the small number of cases, this prospective study clearly indicates that AgNOR count has a significant prognostic role, at least in renal cell carcinoma.

A technique for the simultaneous compensation of spatial system response, Compton scattering and attenuation in brain SPECT using 99Tcm is described here. The procedure involves the acquisition of experimental information relative to spatial response, attenuation and scatter from capillary sources as well as by means of a special experimental set-up. The latter has been accurately designed to isolate the Compton scattering part of the point spread function, by blocking the acquisition of primary gamma rays. The formulation of a physical model allowed a set of weighting factors, which were stored in a disk file, to be calculated. Data were then reconstructed by means of the conjugate gradients iterative least-squares technique, with the system matrix modified by the incorporation of the precalculated weighting factors. Experimental projection data relative to phantoms with constant activity along the rotation axis as well as experimental projection data relative to one phantom with variable axial activity, were acquired. Reconstruction of these data shows that a high degree of compensation for attenuation and scatter in brain SPECT is achieved. With respect to the reconstruction algorithms based upon the backprojection of analytically filtered experimental projections, higher spatial resolution together with very good quantitative activity ratios are the main accomplishments of this reconstruction technique. The method has also been applied to in vivo study reconstructions.

OBJECTIVE To investigate metabolic disturbances, possibly leading to stone disease, in the Camey II technique for creating a urinary reservoir from an intestinal segment. PATIENTS, SUBJECTS AND METHODS Thirty patients with a Camey II ileal neobladder and 26 controls had metabolic investigations of blood samples, and 24-h and fasting urine samples, to assess renal function, the risk of stone formation, and bone turnover. The state of saturation with calcium oxalate, uric acid and brushite were calculated using a computer program. RESULTS The patients had lower renal clearances than the controls (P