Increasing the Resolution of Transmission Electron Microscopy by Computational Ghost Imaging.

By means of numerical simulations, we demonstrate the innovative use of computational ghost imaging in transmission electron microscopy to retrieve images with a resolution that overcomes the limitations imposed by coherent aberrations. The method requires measuring the intensity on a single pixel detector with a series of structured illuminations. The success of the technique is improved if the probes are made to resemble the sample and the patterns cover the area of interest evenly. By using a simple 8 electrode device as a specific example, a twofold increase in resolution beyond the aberration limit is demonstrated to be possible under realistic experimental conditions.

Barrier methods used to prevent pelvic adhesions in videolaparoscopy: experimental study in female rabbits.

BACKGROUND: This study was designed to evaluate the effectiveness of barrier methods to prevent adhesions in videolaparoscopy, comparing the use of Surgicel(®) and Interceed(®) with the control group. METHODS: We performed a controlled, randomized study in healthy adult female rabbits Oryctolagus cuniculu, inducing adhesions in the abdominal wall by resection of a peritoneal fragment and cauterization. In the control group, surgery was performed, and the other group was randomized to the use of the barrier method. After 21 days, videolaparoscopy was repeated, and the presence or absence of adhesions and their score were verified by performing biopsies of the surgical site in all groups. RESULTS: No statistical differences were found in the results on adhesion formation and adhesions score among the three groups. In the control group, there were 54.5% cases of adhesion formation; the median score of adhesions was 6 (range, 3-10). In the Surgicel(®) group, there were 45.5% cases of adhesion formation; median score of adhesions was 6 (range, 4-10). In the Interceed(®) group, there were 45.5% cases of adhesion formation; median score of adhesions was 5 (range, 3-11). CONCLUSIONS: No difference was found using barrier methods, Surgicel(®), and Interceed(®) for preventing adhesion formation in videolaparoscopy.

Alignment of electron optical beam shaping elements using a convolutional neural network.

A convolutional neural network is used to align an orbital angular momentum sorter in a transmission electron microscope. The method is demonstrated using simulations and experiments. As a result of its accuracy and speed, it offers the possibility of real-time tuning of other electron optical devices and electron beam shaping configurations.

Molecular mechanism of myoglobin autoxidation: insights from computer simulations.

Myoglobin (Mb) and hemoglobin have the biological ability to carry/store oxygen (O2), a property which requires its heme iron atom to be in the ferrous--Fe(II)--state. However, the thermodynamically stable state in the presence of O2 is Fe(III) and thus the oxidation rate of a globin is a critical parameter related to its function. Mb has been extensively studied and many mutants have been characterized regarding its oxygen mediated oxidation (i.e., autoxidation) rates. Site directed mutants in residues 29 (B10), which shapes the distal cavity, and 64 (E7), the well-known histidine gate, have been shown to display a wide range of autoxidation rate constants. In this work, we have thoroughly studied the mechanism underlying the autoxidation process by means of state-of-the-art computer simulation methodologies, using Mb and site directed mutants as benchmark cases. Our results explain the observed autoxidation rate tendencies in different variants of Mb, L29F < wt < L29A = H64Q < H64F < H64A, and shed light on several aspects of the reaction at the atomic level. First, water access to the distal pocket is a key event and the observed acid catalysis relies on HisE7 protonation and opening of the His gate to allow water access, rather than protonation of the oxy heme itself. Our results also suggest that the basic mechanism, i.e., superoxide displacement by hydroxide anion, is energetically more feasible. Finally, we confirmed that distal hydrogen bonds protect the oxy complex from autoxidation.

Acute renal failure in the patient undergoing cardiac operation. Prevalence, mortality rate, and main risk factors.

A total of 775 consecutive patients who survived the first 24 hours after cardiac operation were prospectively studied to assess the prevalence, mortality rate, and main risk factors for development of new acute renal failure. Normal renal function before operation (serum creatinine level less than 1.5 mg/dl) was registered in 734 (94.7%) patients. Of these, 111 (15.1%) showed a postoperative renal complication including 84 (11.4%) classified as renal dysfunction (serum creatinine level between 1.5 and 2.5 mg/dl) and 27 (3.7%) as acute renal failure (serum creatinine level higher than 2.5 mg/dl). The mortality rate was 0.8% in normal patients, 9.5% in patients with renal dysfunction, and 44.4% when acute renal failure developed (p < 0.0001). Indeed, the renal impairment proved to be an independent predictor of mortality (p < 0.001), along with the infective (p < 0.001), gastrointestinal (p < 0.001), and cardiovascular (p < 0.05) complications. Multivariate analysis identified the following variables as independent risk factors for postoperative renal impairment: use of intraaortic balloon pump (p < 0.0001), need for deep hypothermic circulatory arrest (p < 0.005), low-output syndrome (p < 0.005), advanced age (p < 0.005), need for emergency operation (p < 0.025), and low urinary output during cardiopulmonary bypass (p < 0.05). The 41 patients (5.3%) with preoperative renal failure showed a significantly higher morbidity and mortality rate than those without renal complications before operation. We conclude that in patients undergoing cardiac operation without preexisting renal dysfunction the likelihood of severe renal complications is reasonably low, but the associated mortality remains high. A prominent role in the development of postoperative acute renal failure must be recognized for preoperative, intraoperative, and postoperative hemodynamic factors, whereas cardiopulmonary bypass seems to be of lesser importance in this respect.

Real-time transrectal sonographic voiding cystourethrography.

Transrectal linear array transducer makes possible a sagittal view of the bladder base-plate, prostatic urethra, and membranous urethra yielding an image similar to that obtained with voiding cystourethrogram. This permits lack of time limitation, such as imposed by the use of fluoroscopy, and the possibility of visualizing not only the lumen of the bladder neck and urethra but also the surrounding soft tissue. Using ultrasonographic urodynamics in neuromuscular dysfunctions of the bladder and urinary voiding obstructions we obtained excellent results in patients with detrusor-sphincter dyssynergia and in those with posterior ledge at the bladder neck. Both conditions are clearly visualized, particularly the existence of the posterior ledge which is responsible for the failure of the sphincterotomy in patients with periurethral striated sphincter spasm.

Prostate cancer: correlation between local and systemic disease.

BACKGROUND: Prostate cancer is in Italian men the second neoplasm for incidence. Transrectal ultrasonography (TRUS) is still today a cheap test, not very invasive, well accepted by the motivated patient and sufficiently accurate for the valuation of the local status disease. We proposed our data to verify if a careful local ultrasonographic study of prostatic carcinoma could or not predict its systemic course. METHODS: We have valued 136 out patients affected by prostate cancer and treated with either palliative medical therapy or radiotherapy. The follow-up varies from 12 to 132 months. The local, evaluation of the disease done through TRUS in longitudinal and/or axial scan (the dimension of the gland, the volume and ultrasonographic characteristics of the lesion, capsular involvement and estimation of the surrounding structures: seminal vesicles, vesica, rectum). RESULTS: In the long run, considering the local and systemic course of the disease, we have noticed accordance globally in 116 patients (85.3%); 13 patients showed only systematic progression (9.5%) while in 7 patients, we have noticed a local but not a systemic variation. CONCLUSIONS: We can deduce that periodical carrying-out of the TRUS (twice a year) constitute a reliable index not only of local procedure of the pt. but also predicting the systemic course of the disease, making the routine carrying out of the other check-up unnecessary, that could be reserved for cases with precise clinical indication.

[Vesico-cutaneous fistula of the thigh as a late manifestation]. / Fistola vescico-cutanea della coscia a manifestazione tardiva.

Vesico-cutaneous fistulas rarely occur in the urinary tract (1.7% of all urinary fistulas). Trauma, neoplasias, inflammation and iatrogenic pathologies are among the principal causes. The external mouth of the fistula is usually found in the hypogastric area, scrotum, perineum and rarely elsewhere. This report describes the case of a 48 year old woman who, after severe trauma suffered bladder laceration, treated only with cystorraphy. Sepsis and gangrene followed involving the pubic area and the right thigh, associated with acute renal and adrenal gland cortex failure. After emergency treatment, the patient was discharged with an indwelling catheter. Ten months later she was referred to our urology clinic because of a suspected bladder-vaginal fistula. The indwelling catheter was removed and the bladder resumed functioning well. Six months later the external mouth of the fistula appeared on the right inner thigh. NMR confirmed the diagnosis of a vesico-cutaneous fistula. Surgery resolved the abnormality.

[The clinician's need in renovascular hypertension]. / Le esigenze del clinico nell'ipertensione reno-vascolare.

Clinician questions in nephrovascular hypertension are: 1) Is hypertension secondary to nephrovascular disease? 2) Is vascular obstruction susceptible of surgical management? 3) Which is the best technical approach? In this review of recent international literature we have focused diagnostic value of echo-color Doppler in the screening of patients with secondary hypertension. The sensibility and specificity of this diagnostic test reach 89% and 99.5%. Respectively when the stenosis is over 70%. Anyway when the stenosis is under 70% the accuracy of this examination is lower. Angiography remains the gold standard test in patient eligible for surgery, although its invasiveness. Diagnostic tests of the renin-angiotensin axis (e.g. Captopril test) are useful too, but morphologic evidence is not provided. Surgical approach is the best choice in elective patients.

[Cystic renal pathology]. / Patologia renale cistica.

Ultrasonography has a great interest in diagnosis of cystic kidney disorders for typical eco-pattern of this pathology. In this work we show the eco-pattern of the most common cystic kidney disorders. Particularly we examine simple cysts (typical, atypical, complicated), multicystic kidney dysplasia, autosomal recessive polycystic kidney disease (infantile) autosomal dominant polycystic kidney disease (adult age). The so-called neoplastic cysts (multiloculated cysts, multiloculated cysts nephroma, cystic nephroblastoma), medullar cysts (medullary sponge kidney, medullary cystic disease), parapyelic cysts, acquired cystic kidney disease in renal failure patients, parasitic cysts, epidermoid cysts. About this disorders we present the more typical and expressive ultrasonographic appearance and we define the role and the opportunity of diagnostic setting by echography, moreover ultrasonography allows us to make a differential diagnosis between cystic kidney disorders and other kidney disease.

[Ultrasonography and Doppler color ultrasonography in kidney neoplasms: the demands of the clinician]. / Ecografia ed eco-color Doppler nella patologia neoplastica del rene: le esigenze del clinico.

The high number of diagnostic methods for images (ultrasound, computer tomography--CT, magnetic nuclear resonance--MNR) has allowed the urologist diagnosis more precocious of renal masses contributing to increase the survival rate and quality of life of patients affected by renal carcinoma. Although many are the advantages that the ultrasound scan gives to the urologist, still today in presence of ultrasound scan results showing expansive renal masses, probably malignant, many perform a CT or MNR for diagnostic confirmation and tumor extension.

[Role of Doppler color ultrasonography in the diagnosis of renovascular abnormalities associated with stenosis of the pyeloureteral junction]. / Ruolo dell'eco-color Doppler nella diagnosi di anomalie vascolari renali associate a stenosi della giunzione pieloureterale.

The obstruction of the pielo-ureteral junction, in most of the cases, recognizes an intrinsic etiopathogenesis, the presence of a segment ureteral aperistaltic and alteration of the ureteral musculature. The association of GPU stenosis and the presence of vascular anomalous shanks are frequent. The knowledge of this anatomical situation is important for choosing the therapeutic strategy and the surgical technique. The pre-operative diagnosis of the anomalous vase could condition the choice of the technique (endoscopic technique, laparoscopic), opting for open surgery to have a better control of the vascular shank. We have examined the use of the echo-color Doppler to diagnose the presence of anomalous vase. We have studied 13 patients (6 men and 7 women) between 18 and 62 years of age (average 35 years); the side interested by the obstruction was in 8 cases the right and in 5 cases the left. During surgery in 4 cases out of 13 examined anomalous vases were present. The pre-operative color Doppler found 3 anomalous shanks with a negative false, a positive false and 8 negative trues, showing a sensibility of 75%, a specificity of 88% with a global diagnostic ability of the 84%. We therefore believe that the echo-color Doppler is reliable enough in the pre-operative diagnosis of vascular anomalies associated to stenosis of the GPU and that could be used for pre-operative diagnosis of this urological affection.

[Ultrasonographic study of urethral sphincter in vesico-sphincter dyssynergia]. / Lo studio ecografico dello sfintere uretrale nella dissinergia vescico-sfinterica.

The ultrasound study of bladder neck and urethral sphincter in men could be performed by means of transrectal ultrasound scan in longitudinal scanning or by probing the surface in transperineal scanning. The endocavitary ultrasound scan study gives the best indications in the evaluation of the bladder neck in men. The neuromuscular bladder dysfunctions' (neurologic bladder), which can be studied by ultrasound scan are dyssinergia, striped detrusor, detrusor-bladder-neck dyssinergia, detrusorial iper-reflexy bladder instability. In paraplegic subjects the exam should be performed in gynecological position or in side decubitus, and micturition is obtained by means of sovrapubic percussion and compression or with prevailing action of the abdominal press. The detrusor-striped dyssinergia is the dysfunction of the bladder where the ultrasound scan results are more meaningful and give the best elements. In these cases, already in basal conditions, could be present a bladder neck half-opened. During micturition there is an ample opening of the bladder neck and of the prostatic urethra, but scarce relaxation of the membranous urethra; sometimes a protrusion of the back lip of the bladder neck could be present too. In iper-reflexy (unstable bladders) and in detrusorial ipo-reflexy, ultrasound scans could result poorly specific and non-significative.

[Echographic study of the bladder neck and prostate region after Nd-Yag laser treatment]. / Studio ecografico del collo vescicale e della loggia prostatica dopo trattamento con Nd Yag Laser.

The authors describe the ultrasonic images they obtained in the follow up of three groups of patients who were divided according to basic pathology and treated with Nd: Yag Laser with contact (CLAP) and side firing (VLAP) fibers. Next the great differences noted between the results achieved with ultrasonic investigation and those obtained with flowmeter controls and IPSS are presented. The authors discuss the possible causes of these dissonances and hypothesize a new way to evaluate cervico-urethral de-obstruction: no longer an anatomical technique but a functional one.

[Echo-guided percutaneous drainage of renal cysts]. / Il drenaggio percutaneo ecoguidato delle cisti renali.

Treatment of renal cysts in the ultrasound guided percutaneous drainage, associated with intra-cavital sclerosis-inducing agents to avoid recurrence, is often proposed. This report describes the technique and the most suitable sclerosis inducing agents. The best results are obtained with alcohol. No increase in complications or discomfort was observed.

[Vesico-intestinal fistula in Crohn disease: the role of echography in its diagnosis]. / Fistole vescico-enteriche in corso di morbo di Crohn: ruolo dell'ecografia nella diagnosi.

Ultrasound is in widespread use in the study of gastrointestinal pathologies. In Crohn disease it is helpful in diagnosing complications such as thickening of the bowel loop walls, abscesses, lymph node enlargement and vesical-enteric fistulas. This report presents two cases in which vesical-enteric fistulas were visualized by US; confirming a diagnosis of Crohn's disease in one case, and diagnosing the fistula during the follow-up in the second patient in whom Crohn's disease had previously been diagnosed.

[Echography during drug-induced erections in the study of penile plastic induration]. / Ecografia in corso di erezione farmaco indotta nello studio dell'induratio penis plastica.

Clinical investigation is still fundamental in the diagnosis of La Peyronie's disease. In this study 36 patients underwent clinical investigation and ultrasound in basal conditions and during drug-induced erection, and the results were compared. In basal condition US does not provide much useful supplementary informations. During drug-induced erection US accurately visualizes plaque site and dimensions and anatomical abnormalities about corpora cavernosa, albuginea, septum and dorsal vessels.

[Traumatic injuries of the urethra: an echographic study]. / Lesioni traumatiche dell'uretra: studio ecografico.

US in the lower urinary tract usually explores the bladder and the prostatic urethra. In this study we used US instead of x-rays to visualize the remaining urethra in 42 patients. US was useful in the presence of urethral trauma. The site and extent of injury, particularly peri-urethral lesions (hematomas, urinary collection and abscesses in relation to the urethra) were observed. Ultrasound's efficacy and reproducibility were also useful in post-operative follow-ups.

[Urethral diverticuli in women: role of diagnostic methods in the preoperative assessment]. / Diverticoli uretrali nella donna: ruolo delle metodiche diagnostiche nell'inquadramento preoperatorio.

From 1985 to 1993 we observed 9 female patients with urethral diverticula. All patients underwent first clinical examination and then US (suprapubic and transrectal or transvaginal scans) and X-ray cystography which demonstrated the communication between the diverticula and the urethra, MRI was also performed, in order to explain the rapports between the diverticulum and the sphyncter. All patients underwent surgery and 8 were cured. No cases of incontinence were observed.

[Locally advanced prostatic cancer and systemic involvement]. / Cancro prostatico localmente avanzato ed interessamento sistemico.

In a group of 115 patients with prostatic cancer, the correlation between the local and systemic evolution of the neoplasm has been evaluated. In 80 patients non local and systemic up-staging of the tumor was observed. In further 18 patients both local and systemic staging uppers and in the remaining 17 patients no correlation between local and systemic evolution was observed. In conclusion, in this series, the prostatic cancer demonstrated an high concordance in both local and systemic evolution and then the modifications of local staging can be used as a predictive parameter of systemic evolution of the prostatic cancer.