Understanding of Phase Noise Squeezing Under Fractional Synchronization of a Nonlinear Spin Transfer Vortex Oscillator.

We investigate experimentally the synchronization of vortex based spin transfer nano-oscillators to an external rf current whose frequency is at multiple integers, as well as at an integer fraction, of the oscillator frequency. Through a theoretical study of the locking mechanism, we highlight the crucial role of both the symmetries of the spin torques and the nonlinear properties of the oscillator in understanding the phase locking mechanism. In the locking regime, we report a phase noise reduction down to -90 dBc/Hz at 1 kHz offset frequency. Our demonstration that the phase noise of these nanoscale nonlinear oscillators can be tuned and eventually lessened, represents a key achievement for targeted radio frequency applications using spin torque devices.

Assessment of host defence mechanisms induced by Candida species.

Some species of Candida are opportunistic pathogens that can cause disease in a host immunocompromised by underlying local or systemic pathological processes. C. albicans is the species most often associated with oral lesions, but other species of Candida, including C. glabrata, C. tropicalis and C. parapsilosis, have also been isolated in the saliva of subjects with and without candidiasis. In the present study we evaluated the host defence mechanisms induced by Candida albicans and other Candida species in monocytes and oral epithelial cells in order to establish the existence of a species-specific cellular response. Our results indicated that, during Candida species infection, the epithelial cells actively participate in the host defence by producing antimicrobial peptides and proinflammatory cytokines. Moreover, in infections caused by Candida tropicalis and Candida glabrata, the host defence may be strengthened by the release of perforin and granzyme by polymorphonuclear leukocytes recruited at the site of infection.

Role of high molecular weight hyaluronic acid in postmenopausal vaginal discomfort.

AIM: Aim of the present study was to quantify the intensity of vulvovaginal symptoms before and after treatment with high molecular weight hyaluronic acid (HA), to test the tolerability and safety of the product, to evaluate the effect on the quality of life and the compliance to the treatment. METHODS: This was a double-blind randomized placebo-controlled study. In seven months we enrolled 36 post-menopausal women, equally distributed in placebo and active group. The evaluation was based on at least three atrophy-related signs and on the patient reported symptoms. After the written informed consent, the participants were instructed to apply the gel (drug or placebo) daily. Three days after the end of the treatment the patients received a final examination to evaluate the progress of symptoms, the presence of any adverse events and their correlation with the treatment. RESULTS: Self-evaluation scales and investigator evaluation showed that the vaginal dryness was significantly reduced both in placebo and in the active group; however, high molecular weight HA was the only active treatment in reducing significantly itching and burning (P<0.02 and <0.04 respectively). Both treatments significantly reduced vaginal atrophy (P<0.001), erythema (P<0.01 placebo and P<0.001 HA) and vaginal dryness (P<0.001), but HA treatment was significantly more effective on the first two symptoms. Both treatments were very well tolerated and compliance of the treatment was very high. CONCLUSION: High molecular weight HA could be effective in subjective and objective improvement of postmenopausal vaginal atrophy providing a good compliance. No adverse events occurred during the entire period of the study.

Circulating levels of cytochrome C, gamma-glutamyl transferase, triglycerides and unconjugated bilirubin in overweight/obese patients with non-alcoholic fatty liver disease.

Non-alcoholic fatty liver disease, characterized by hepatocyte apoptosis, is distinct in fatty liver and non-alcoholic steatohepatitis, the more severe form. Apoptotic cell death is caspase-dependent and associated with mitochondrial membrane depolarization and cytochrome c release. Adhering to the hypothesis that the exposure of hepatocytes to free fatty acids, resulting in increased ROS production and mitochondrial damage, is balanced by the presence of antioxidant substances, circulating levels of gamma-glutamyl transferase, cytochrome c, triglycerides and unconjugated bilirubin were explored in patients suffering from non-alcoholic fatty liver disease with different severity. One hundred and eighty-six consecutive patients who presented recent ultrasound feature of bright liver without any liver disease of known origin were enrolled, eighty-nine of whom underwent liver biopsy. Forty-five subjects were allocated on the basis of histology in fatty liver group while 44 patients formed the group with non-alcoholic steatohepatitis. A cohort of 27 young, lean, apparently healthy individuals was selected as control group. The levels of gamma-glutamyl transferase were normal or slightly increased, while unconjugated bilirubin concentrations were elevated in all the spectra of non-alcoholic fatty liver disease. Comparing the present results with relevant findings from other studies dealing with diseases characterized by apoptosis, we did not find high circulating levels of cytochrome c in non-alcoholic fatty liver disease. What is more, our patients, categorized as suffering from simple fatty liver or from the more severe non-alcoholic steatohepatitis, had similar levels of cytochrome c and gamma-glutamyl transferase, p=0.19 and 0.11. Serum triglycerides were higher in patients with non-alcoholic fatty liver disease than in the healthy group, p=0.001. These findings likely reflect a balance between oxidative stress and anti-oxidant response rather than a lack of reliability of cytochrome c as a reliable biomarker of mitochondrial damage.

Real-time Hall-effect detection of current-induced magnetization dynamics in ferrimagnets.

Measurements of the transverse Hall resistance are widely used to investigate electron transport, magnetization phenomena, and topological quantum states. Owing to the difficulty of probing transient changes of the transverse resistance, the vast majority of Hall effect experiments are carried out in stationary conditions using either dc or ac. Here we present an approach to perform time-resolved measurements of the transient Hall resistance during current-pulse injection with sub-nanosecond temporal resolution. We apply this technique to investigate in real-time the magnetization reversal caused by spin-orbit torques in ferrimagnetic GdFeCo dots. Single-shot Hall effect measurements show that the current-induced switching of GdFeCo is widely distributed in time and characterized by significant activation delays, which limit the total switching speed despite the high domain-wall velocity typical of ferrimagnets. Our method applies to a broad range of current-induced phenomena and can be combined with non-electrical excitations to perform pump-probe Hall effect measurements.

Does spleen volume play a role in patients with HCV-related chronic hepatitis?

As the lymphotropism of hepatitis C virus (HCV) has already been ascertained, and in the light of the fact that the immune defense system is an organized network composed of functionally interrelated tissues, this study was carried out to verify the possible involvement of spleen in HCV-related chronic hepatitis. In this cross-sectional study we measured spleen longitudinal diameter by ultrasound, beta2-microglobulin serum levels and splenic artery resistivity index (SARI) by Doppler in 51 patients treated with standard combined (Peg-Interferon plus Ribavirin) antiviral therapy. Thirty-three patients (17 females) completed the regimen and were compared to 31 controls (16 females). The mean basal values of spleen longitudinal diameter were higher in patients with chronic hepatitis than in controls, i.e., 116 mm (9.4) versus 102.7 mm (9.3), P = 0.0001. In the same patients a significant trend towards increased spleen longitudinal diameter was found after antiviral therapy, independently of the stage of HCV-related chronic hepatitis. The median values of the beta2-microglobulin concentrations were not significantly higher in the patients with HCV-related chronic hepatitis compared to controls, i.e., 1.3 (0.5-2.6) versus 1 (0.6-1.4), P = 0.16, although during the course of therapy they were significantly increased. SARI values of HCV-related chronic hepatitis patients were different from those of controls, but were unvaried compared to values at the end of treatment. Neither spleen measurements nor serum beta2-microglobulin levels were able to predict therapeutic response to antiviral therapy. A stimulation/expansion of lymphoid tissue was found in patients with HCV-related chronic hepatitis. Such evidence raises the question whether physicians should continue to prescribe antiviral therapy in non-responders and supports the use of a new scheme (SLD plus beta2-MG) to diagnose this ongoing, apparently reversible, but nevertheless dangerous immunologic process.

Spin-torque resonant expulsion of the vortex core for an efficient radiofrequency detection scheme.

It has been proposed that high-frequency detectors based on the so-called spin-torque diode effect in spin transfer oscillators could eventually replace conventional Schottky diodes due to their nanoscale size, frequency tunability and large output sensitivity. Although a promising candidate for information and communications technology applications, the output voltage generated from this effect has still to be improved and, more pertinently, reduces drastically with decreasing radiofrequency (RF) current. Here we present a scheme for a new type of spintronics-based high-frequency detector based on the expulsion of the vortex core in a magnetic tunnel junction (MTJ). The resonant expulsion of the core leads to a large and sharp change in resistance associated with the difference in magnetoresistance between the vortex ground state and the final C-state configuration. Interestingly, this reversible effect is independent of the incoming RF current amplitude, offering a fast real-time RF threshold detector.

Evaluation of the Abbott CELL-DYN 4000 hematology analyzer.

A new generation hematology analyzer, Abbott CELL-DYN 4000 (CD 4000), capable of providing 26 parameters, including fully automated reticulocyte, nucleated RBC, blast, band, and immature granulocyte, and variant lymphocyte counts, was evaluated by using the National Committee for Clinical Laboratory Standards H20-A protocol and compared with the Bayer-Technicon H-2 analyzer, which is used routinely in our laboratory. A lipid interference experiment and a sample aging study also were performed. Linearity, carryover, and precision were within the limits established by the manufacturer, and satisfactory agreement was found with the H-2 analyzer. The evaluation of leukocyte differential counts indicated an excellent correlation with the manual reference method for neutrophils and lymphocytes, a good correlation for monocytes and eosinophils, and a poor correlation for basophils in samples with low counts; for basophil counts of 2% or higher, we found an improvement of the correlation coefficient. In the lipid interference experiment, only hemoglobin determination was influenced significantly on the CD 4000, but by using a new Abbott hemoglobin reagent, the interference was eliminated. The CBC and differential counts were stable and reportable up to at least 24 hours. Intrasample viability information on leukocytes provided a quality check on each individual specimen.

Evidence of a cold immunoglobulin M autoantibody against 78-kD platelet glycoprotein in a case of EDTA-dependent pseudothrombocytopenia.

Pseudothrombocytopenia is a phenomenon in which the electronic count shows spuriously low platelet counts in subjects with normal platelet levels. The mechanism of anticoagulant-dependent pseudothrombocytopenia appears to involve cold reactive agglutinins against platelet antigens. The authors report a case of EDTA-dependent pseudothrombocytopenia with evidence of a cold immunoglobulin M antibody against 78-kD platelet membrane glycoprotein (GP). Cell counts were performed by Coulter Counter S-Plus VI (Coulter, Hialeah, FL) in the following anticoagulants: EDTA, Na-citrate, and citrate-theophylline-adenosine-dipyridamole. Anti-platelet antibodies and platelet membrane GP antigens were assayed by an immunofluorescence technique as described by Van dem Borne in 1978. An immunoglobulin M/lambda anti-platelet antibody was found to react in serum as well as in plasma EDTA at room temperature, but not at 37 degrees C. This antibody appeared to be directed against GP78 membrane antigen because this antigen was not detectable by immunofluorescence in platelets collected in EDTA and Na-citrate anticoagulant, whereas a fluorescence signal was revealed in platelets collected in citrate-theophylline-adenosine-dipyridamole. This evidence was confirmed by platelet clumping inhibition tests in which target platelets were pretreated with anti-GP monoclonal antibodies. Clumping in the presence of pseudothrombocytopenia serum was inhibited by anti-GP78kD and anti-GPIIb/IIIa but not by anti-Ib. In this case, GP78 appears to be involved in platelet clumping, together with IIb/IIIa complex. The partial inhibition of the phenomenon observed in citrate-theophylline-adenosine-dipyridamole is probably related to a lower expression of the membrane antigens in platelets collected in this anticoagulant.

The urine stream interruption test and pelvic muscle function in the puerperium.

OBJECTIVES: This study assesses the role of the uroflowmetric urine stream interruption test (UST) in the evaluation of postpartum pelvic floor muscle function. METHOD: Two months after vaginal delivery, 492 women who underwent a digital test, vaginal manometry, and a UST were divided into two groups: continent and incontinent. Variables were subjected to the Student's t-test and to Fisher's exact test to verify the difference between the two groups. RESULTS: Digital test and vaginal manometry results were higher in the continent group, but only the UST showed significantly different values (P=0.001). All test results of incontinent puerperae who underwent rehabilitation were significantly improved after treatment. CONCLUSIONS: UST is low cost, non-invasive, and can give objective information about pelvic floor performance after a vaginal delivery. It can be used for both routine clinical use and an outcome measure for women who undergo rehabilitation treatment.

Tuberculosis in marine tropical fishes in an aquarium.

Skin, gill and visceral tubercle lesions were detected in marine tropical fish in an aquarium. Ninety-seven fish of 17 different genera were affected. The tubercles consisted of a wall of densely packed epithelioid cells and necrotic center packed with acid-fast bacilli identified as Mycobacterium marinum.

[Postpartum perineal assessment]. / Valutazione perineale postpartum.

BACKGROUND: To evaluate the incidence of urogenital and anorectal dysfunctions during puerperium, verify the correlation between obstetric perineal damage observed during labour and puerperal symptoms, test the efficacy of tests to evaluate perineal function in pelvic floor dysfunctions consequent to vaginal birth. METHODS: A total of 693 consecutive puerperae were recruited two months after birth. All completed a clinical and anamnestic questionnaire and underwent clinical urogynecological examination, digital test, vaginal manometry and uroflowmetric evaluation of the voluntary capacity to interrupt micturition. From a statistical point of view, persistent urinary incontinence was identified by graphic representation on frequency tables and predictive tests, and statistical "kappa" was used to evaluate the correlation between perineal function tests. RESULTS: Stress urinary incontinence (15.1%) represents the most widespread symptom, a postpartum perineal inspection provides a sufficiently accurate estimate of posterior damage, but does not identify those puerperae who will develop urinary incontinence. None of the tests used was able to predict persistant urinary incontinence. CONCLUSIONS: Postpartum perineal inspection seems to be effective in predicting anorectal dysfunctions, but is not so useful for urethro-vesical disorders. None of the diagnostic methods examined allowed a sufficiently accurate selection of those puerperae at risk.

[Typification of HPV in clinical practice]. / Tipizzazione dell'HPV nella pratica clinica.

OBJECTIVE: To improve the sensitivity of cervical carcinoma screening and to determine the optimal management with an ASCUS Pap result we evaluated the effectiveness of combining thin layer cytologic slides (ThinPrep) and HPV DNA testing. METHODS: A total of 170 women were studied with conventional Pap smears, liquid based cytology, HPV testing and colposcopy with eventual histologic evaluation. RESULTS: The ThinPrep method yielded 12.5% more high grade lesions than did the conventional smears (and more severe diagnoses as compared to the conventional smears). HPV prevalence was significantly associated with disease status. Of 30 patients with ASCUS, HPV testing detected 100% of high grade lesions and 67% of low grade. If colposcopy had been limited to HPV+ women, 47% of case would have been spared. CONCLUSIONS: Liquid based cell collection improves sensitivity for the detection of disease. For women with ASCUS cytology, HPV DNA testing of residual specimen can identify the majority of high risk cases using a single sample.

[Insulinemic response to oral glucose loading tests in screening for diabetes in pregnancy]. / Risposta insulinemica al carico orale di glucosio nei test di screening del diabete gestazionale.

BACKGROUND AND AIMS: Given that an increased peripheral insensitivity to insulin represents the primum movens of gestational diabetes, it is reasonable to suppose that the determination and evaluation of the insulinemic response to an oral glucose loading test may represent a simple, effective and low cost screenign test. A method was devised which consisted in performing two assays of insulin and glycemia in venous blood; the first while fasting, the second one hour after the ingestion per os of 50 g glucose. METHODS: A group of 79 pregnant women, aged between 20 and 41 years old (mean age 30.5), was tested in around the 23rd week of gestation. All women were attending the Obstetric and Gynecological Clinic at Trieste University. RESULTS: Based on the results obtained, insulinemic parameters appear to be significantly correlated with data for the short glycemic curve according to O'Sullivan-Mahan. CONCLUSIONS: This study appears to confirm the need to include insulinemic tests as part of the new and more efficacious glucose tolerance tests and to perform prospective studies in order to identify the most reliable screening method in terms of sensitivity and specificity, also in relation to the cost-benefit ratio.

[Magnetic resonance (MR) in endometrial carcinoma preoperative evaluation]. / Impiego della risonanza magnetica (RM) nella valutazione preoperatoria del carcinoma endometriale.

BACKGROUND: Myometrial invasion of endometrial carcinoma is an important prognostic factor because the degree of myometrial invasion is correlated with the rate of lymphnode metastases and of recurrences. The aim of the study was a preoperative evaluation of endometrial carcinoma by Magnetic Resonance (MR). METHODS: The authors present a prospective study performed on 54 cases of endometrial carcinoma collected at the Department of Gynecology and Obstetrics of the University of Trieste (Italy). All the patients were considered as Stage I after hysteroscopy and endocervical curettage. Prior to surgery all the patients underwent MR at the Department of Radiology of the University of Trieste (Italy) in order to evaluate the depth of myometrial invasion. The surgical procedure included total abdominal hysterectomy, bilateral salpingo-oophorectomy and pelvic and lomboaortic lymphadenectomy in high risk cases. Statistical evaluation was performed by Fischer's exact test. RESULTS: Statistically significant positive correlation was found (p<0.001) between MR staging and surgical staging. The sensitivity reported in our series for distinguishing between superficial disease (Stage IA and IB) and deep myometrial invasion (Stage IC) was 92%. CONCLUSIONS: Preoperative MR is helpful in selecting patients at high risk of nodal involvement and it is suggested that, although MR is considered an expensive examination, its use should be always considered before surgical treatment of patients with high surgical risk.

[Pregnancy cholestasis. Clinical aspects and neonatal outcome]. / Colestasi gravidica. Aspetti clinici ed outcome neonatale.

AIM: Gravidic cholestasis is a syndrome that is usually manifested during the third trimester of pregnancy and regresses in puerperium. It is characterized by the onset of itch, with or without associated jaundice and alterations of hepatic functional parameters. Its incidence varies according to geographical area. METHODS: A retrospective analysis was made regarding the frequency of this pathology in pregnant patients attending the Gynecology and Obstetrics Clinic of Trieste from 1-1-1980 to 31-7-1997. The epidemiological and clinical characteristics were studied relating to the course of pregnancy and neonatal outcome. Patients were identified on the basis of diagnosis on admittance and anamnestic and laboratory data, generalised itch and increased transaminase, biliary salts and alkaline phosphatase. Patients suffering form active-phase viral hepatitis were excluded, as were those in whom symptoms appeared after the start of alpha methyldopa administration. RESULTS: The frequency of gravidic cholestasis in this series was 0.36%. No significant differences were recorded in terms of age, parity and weight increase in these patients compared to the general population of pregnant women. Birth was spontaneous in 66% and by cesarean section in 34%. The frequency of premature births was 12%. The Apgar score at 5 min was satisfactory in all neonates. CONCLUSIONS: Careful monitoring of pregnancy associated with suitable obstetric care enabled a zero rate neonatal and maternal mortality to be achieved.

[Gynecologic infections in adolescence]. / Le infezioni ginecologiche nell'adolescenza.

BACKGROUND: Adolescence in the age bracket with the highest incidence of sexually transmitted diseases (STDs). An observational study was performed in symptomatic patients attending our Outpatient Clinic for STDs in order to evaluate the diffusion of genital infections in the adolescent population and the different epidemiological distribution compared to adults. METHODS: The incidence of these infections was compared in two groups of patients attending the clinic between April 1995 and April 1999. The first consisted of 54 teenagers (13-19 years-old) and the second, used as a control, consisted of 917 women of child-bearing age (20-40 years). All patients underwent clinical examinations and microbiological tests of vaginal secretions (bacterioscopic test on coloured plates using the Gram method, cold tests, cultural assay of bacteria and fungi, assay for (Chlamydia trachomatis, Mycoplasma spp., Neisseria gonorrhoeae, Herpes simplex virus). RESULTS: The most common genital infection in teenagers was candidosis (35% vs 23.9%), followed by bacterial vaginosis (31.9% vs 25.8%) and mixed flora vaginitis (25.9% vs 22.6%). HSV was found in 1.8% of adolescents (vs 0.6%), in selected cases, Chlamydia and Mycoplasma were present in 16.6% (vs 1.1%) and 50% (vs 28%) of teenagers respectively. CONCLUSIONS: All genital infections were more frequent in the study population of adolescents compared to the control group. The adolescent population should be the target of a serious and systematic programme of prevention in order to ward off the sequelae of early and often irresponsible sexual activity.

[Sexual behavior and adolescence]. / Costumi sessuali ed adolescenza.

BACKGROUND: Adolescence represents the period with the highest frequency of negative consequences associated with sexual activities (sexually transmitted diseases and unwanted pregnancies). An epidemiological study was carried out in symptomatic patients attending our Outpatient Clinic for Sexually Transmitted Diseases between April 1995 and April 1999 in order to evaluate the behaviour pattern of the adolescent population and identify the differences compared to the adult population. METHODS: A questionnaire was used to assess the characteristics of two groups of patients: the first consisted of 54 teenagers (13-19 years-old) and the second, the control group, consisted of 917 women aged between 20 and 40 years old. RESULTS: A high percentage of pregnancies (22.2%) and voluntary abortions (41.6%) was observed in teenagers, associated with different sexual behaviours. The age of sexual intercourse was below 15 in 44.4% of adolescents (vs 7.7% of controls), whereas 61.1% had more than one sexual partner and 20.4% had changed partners in the last 6 months (vs 7.4%). 50% of teenagers did not use any method of contraception (vs 44.2%) and barrier methods were only used by 20.4% (vs 18.4%). CONCLUSIONS: Our study confirms the existence of a high-risk behavioural pattern in the adolescent population and draws attention yet again to the need for a serious programme of prevention and sexual education which will allow adolescents to experience the discovery of their own sexuality with greater awareness and safety.

[Sexually transmitted diseases in adolescence]. / Le malattie sessualmente trasmesse in età adolescenziale.

BACKGROUND: Sexually transmitted diseases (STD) have their most incidence in adolescence. We conducted an observational study on the symptomatic patients of our STD's office to evaluate epidemiological distribution, behavioral patterns and diffusion of genital infections in teen-agers in respect of the adult population. METHODS: From april 1996 to april 1999 we studied two groups of patients: 54 teen-agers (13-19 years) and 917 women in fertile age (20-40 years). All the patients underwent to a clinical and microbiological examination of vaginal secretions (Gram slide, wet mount, cultures for bacteria, yeasts, eventually Chlamydia trachomatis, Mycoplasma spp, Neisseria gonorrhoeae, Herpes simplex virus--HSV--) and to an anamnestic and socio-epidemiological questionnaire. RESULTS: The more frequent genital infections among adolescents was vulvovaginal candidiasis (35% vs. 23.9% of adult people). HSV was found in 1.8% of teen-agers (vs. 0.6%) and when requested, Chlamydia trachomatis and mycoplasmas was found respectively in 16.6% (vs. 1.1%) and 50% (vs. 28%) in adolescents. We observed a high percentage of pregnancy (22.2%) of voluntary pregnancy interruption (41.6%) and a specific sexual behavior among teenagers. CONCLUSIONS: Our data show a particular behavioral risk pattern in the adolescence population and indicate the necessity of a serious program of prevention and sexual education that allow young people to live with more consciousness and safety their sexuality.

Essential mixed type II cryoglobulinemia in a HCV positive pregnant woman: case report.

Cryoglobulins are a group of proteins with the common property of precipitating from cooled serum. Cooled cryoglobulinemia is a classic disease caused by immune complexes which subside on vessel walls and produce a clinical picture represented by recurrent purpura, asthenia, arthralgias, Raynaud's phenomenon, glomerulonephritis and sensorimotor neuropathy. The authors describe a case of a patient C.M., 37 years old, with cryoglobulinemia, chronic hepatitis C and gravidic cholestasis at 28 weeks' gestation. The clinical picture worsened with the appearance of mild hypertension with proteinuria and hypochromic anaemia. At 31 weeks' the arthralgic symptomatology and pruritus revealed degeneration with an alteration of glycemic profile values and treatment with rapid human insuline was started. The cardiotocography began to be pathologic and a cesarean section was performed; the newborn weighted 1570 g. Cooled cryoglobulinemia is a pathology which worsens in a gravidic state and can impair the outcome of pregnancy.