Programmable system on chip for controlling an atomic physics experiment.

Most atomic physics experiments are controlled by a digital pattern generator used to synchronize all equipment by providing triggers and clocks. Recently, the availability of well-documented open-source development tools has lifted the barriers to using programmable systems on chip (PSoCs), making them a convenient and versatile tool for synthesizing digital patterns. Here, we take advantage of these advancements in the design of a versatile clock and pattern generator using a PSoC. We present our design with the intent of highlighting the new possibilities that PSoCs have to offer in terms of flexibility. We provide a robust hardware carrier and basic firmware implementation that can be expanded and modified for other uses.

A radiofrequency voltage-controlled current source for quantum spin manipulation.

We present a wide-bandwidth, voltage-controlled current source that is easily integrated with radiofrequency magnetic field coils. Our design uses current feedback to compensate for the frequency-dependent impedance of a radiofrequency antenna. We are able to deliver peak currents greater than 100 mA over a 300 kHz to 54 MHz frequency span. The radiofrequency current source fits onto a printed circuit board smaller than 4 cm2 and consumes less than 1.3 W of power. It is suitable for use in deployable quantum sensors and nuclear magnetic resonance systems.

Microcontroller based scanning transfer cavity lock for long-term laser frequency stabilization.

We present a compact all-digital implementation of a scanning transfer cavity lock (STCL) for long-term laser frequency stabilization. An interrupt-driven state machine is employed to realize the STCL with the capability to correct for frequency drifts in the slave laser frequency due to measured changes in the lab environmental conditions. We demonstrate an accuracy of 0.9 MHz for master laser and slave laser wavelengths of 556 nm and 798 nm as an example. The slave laser is also demonstrated to dynamically scan over a wide frequency range while retaining its lock, allowing us to accurately interrogate atomic transitions.

A low-steering piezo-driven mirror.

We present a piezo-driven translatable mirror with excellent pointing stability, capable of driving at frequencies up to tens of kilohertz. Our system uses a tripod of piezo actuators with independently controllable drive voltages, where the ratios of the individual drive voltages are tuned to minimize residual tilting. Attached to a standard ∅ = 12.7 mm mirror, the system has a resonance-free mechanical bandwidth up to 51 kHz, with displacements up to 2 µm at 8 kHz. The maximum static steering error is 5.5 µrad/µm displaced, and the dynamic steering error is lower than 0.6 µrad µm-1. This simple design should be useful for a large set of optical applications where tilt-free displacements are required, and we demonstrate its application in an ensemble of cold atoms trapped in periodically driven optical lattices.

Toe web intertrigo in Kaposi's sarcoma patients: a microbiological study in a large cohort of patients.

Kaposi 's sarcoma (KS) is a rare multifocal angioproliferative disease associated with human herpes virus 8 (HHV-8) infection, characterized by cutaneous nodules or plaques especially on the lower limbs. Some skin modifications, such as chronic lymphedema, plantar hyperkeratosis and interdigital desquamation, may be associated with consequent impairment of the local immunosurveillance and increased risk of some bacterial or mycotic infections. With the objective of evaluating if bacterial or mycotic infections in KS patients are supported by different microorganisms compared to control patients, we performed an observational retrospective study, comparing positive cultural swabs of interdigital intertrigo of KS patients with positive cultural swabs of interdigital intertrigo of patients admitted to our dermatologic unit during the last 10 years. One hundred KS patients and 84 control patients were admitted to this study. Some of the skin swabs from interdigital spaces were positive for more than one microorganism, and therefore we found 187 microorganisms among the KS group and 182 microorganisms in the control group. The most common microrganisms among KS patients were T. mentagrophytes (16%), S. aureus (14.9%), P. aeruginosa (13.9%), S. marcescens (5,9%), while among non-KS patients were S. aureus (26,9%), C. albicans (22%), S. agalactiae (7.7%) and E. coli (9.9%). These differences are statistically significant (p < 0.01). KS patients may be more affected by toe web intertrigo due to other bacteria and dermatophytes than the general population. During clinical examination, a careful inspection is necessary for an early diagnosis of toe web intertrigo, in order to prevent serious complications, such as cellulitis and sepsis. Consequently, a cultural examination with antibiogram is required to identify the causative agent of intertrigo and guide antimicrobial therapy.

Active stabilization of ion trap radiofrequency potentials.

We actively stabilize the harmonic oscillation frequency of a laser-cooled atomic ion confined in a radiofrequency (rf) Paul trap by sampling and rectifying the high voltage rf applied to the trap electrodes. We are able to stabilize the 1 MHz atomic oscillation frequency to be better than 10 Hz or 10 ppm. This represents a suppression of ambient noise on the rf circuit by 34 dB. This technique could impact the sensitivity of ion trap mass spectrometry and the fidelity of quantum operations in ion trap quantum information applications.

An ultra-low noise, high-voltage piezo-driver.

We present an ultra-low noise, high-voltage driver suited for use with piezoelectric actuators and other low-current applications. The architecture uses a flyback switching regulator to generate up to 250 V in our current design, with an output of 1 kV or more possible with small modifications. A high slew-rate op-amp suppresses the residual switching noise, yielding a total root-mean-square noise of ≈100 µV (1 Hz-100 kHz). A low-voltage (±10 V), high bandwidth signal can be summed with unity gain directly onto the output, making the driver well-suited for closed-loop feedback applications. Digital control enables both repeatable setpoints and sophisticated control logic, and the circuit consumes less than 150 mA at ±15 V.

Impact of adrenalectomy and dexamethasone treatment on testicular morphology and sperm parameters in rats: insights into the adrenal control of male reproduction.

Here we investigated the hypothesis that normal levels of glucocorticoids, a class of adrenal steroid hormones, are required for normal testicular and epididymal functions. We examined the effects of the manipulation of glucocorticoid plasma levels by bilateral adrenalectomy (1, 2, 7 and 15 days) alone or in combination with daily treatment with the synthetic glucocorticoid dexamethasone (DEX; 5 µg/kg, i.p., 6 days) on the morphology of the testis and sperm parameters in rats. We showed that adrenalectomy led to a reduction in testicular sperm count and daily sperm production starting 2 days after surgery and a differential decrease in sperm count in the epididymis, according to the region and time post-adrenalectomy analysed. In parallel, testes from 7-day adrenalectomized (ADX) rats displayed a higher frequency of damaged seminiferous tubules and the presence of elongated spermatids retained in the basal epithelial compartment in stages IX-XVII, which is indicative of defective spermiation. The alkaline comet assay revealed a late effect of adrenalectomy on epididymal sperm DNA fragmentation, which was increased only 15 days after surgery. DEX treatment prevented the changes in testicular and epididymal sperm count observed in 7-day ADX rats, but failed to protect the testis from ADX-induced morphological abnormalities. Thus, our results indicated that glucocorticoids may be involved in events related to the maintenance of spermatogenesis and sperm maturation during adulthood. These findings provide new insights into the importance of adrenal steroids to male fertility.

Eradication of Chlamydia trachomatis parallels symptom regression in chronic bacterial prostatitis patients treated with a fluoroquinolone-macrolide combination.

To investigate the association between eradication of Chlamydia trachomatis (CT) and symptom regression in chronic prostatitis, 55 symptomatic patients were subjected to segmented tests to localise CT in first voided urine (VB1), prostatic secretions (EPS), post-massage voided (VB3) or semen specimens. Patients were divided in three treatment groups: the 'urethral involvement' group ('U': VB1 positive, EPS/VB3/Semen negative) was treated with 500 mg day(-1) azithromycin for 3 days. The 'prostatitis' group ('P': VB1 negative, EPS/VB3/semen positive) with 4-week levofloxacin-azithromycin combination. A third group, 'U+P' (VB1, EPS/VB3/semen positive) received both treatments in sequence. In P patients, eradication of CT was paralleled by marked, sustained symptom improvement and by significant decrease of serum prostate-specific antigen (PSA) levels. Compared with U patients, undergoing rapid regression of symptoms related to painful micturition after short-term azithromycin, U+P patients showed symptom and pathogen persistence in VB3/EPS/semen and required additional treatment with 4-week levofloxacin-azithromycin to achieve pathogen eradication, symptom regression, and decrease of PSA. Our results support a causative role of CT in chronic bacterial prostatitis. In the presence of a positive urethral localisation of the pathogen, thorough microbiological investigation together with focused symptom analysis may reveal an underlying chlamydial prostatitis and direct effective therapy with appropriate antibacterial agents.

Effect of technological treatments on digestibility and allergenicity of meat-based baby foods.

OBJECTIVE: When suitability prepared according to particular characteristics of hygiene and digestibility, meat is an important food for human weaning. The present knowledge on meat digestibility and allergenicity are not enough to justify removal of meat from a child's diet when there is risk but no clinical evidence of allergy. Based on these considerations, the role of technological treatments on digestibility and allergenicity of meat-based baby foods is considered. SUBJECTS: Eight children (five males and three females) suffering from atopic dermatitis (AD), aged 3.8 to 7.1 years (mean age 4.86 +/- 1.10 years). STUDY DESIGN AND METHODS: An in vitro multienzymatic digestibility assay was used to evaluate proteolysis in meat samples (from four different animal species). The experimental design included raw, steam-cooked (home-made and industrial cooking), homogenized (strained) and freeze-dried meat samples. Skin prick test (SPT) was performed to evaluate positive responses to meat samples (raw, cooked, strained and freeze-dried) from four animal species. RESULTS: Our data indicate that enzymatic attack is strongly affected by heat treatment as shown in steam-cooked meat samples. On the other hand, blending, homogenization and freeze-drying processes are able to partially reverse the phenomenon. Data on modification of sodium dodecyl sulfate-polyacrylamide gel rlectrophoresis (SDS-PAGE) protein pattern during the multienzymatic assay are reported. Cooking and technological treatments reduce positive responses obtained in SPT. CONCLUSIONS: Technological treatments improve digestibility and reduce antigenicity of meat products.

Meat allergy: I--Specific IgE to BSA and OSA in atopic, beef sensitive children.

OBJECTIVE: The use of lamb meat products has been suggested as an alternative diet for polyallergic children, although until now this clinical practice has not been supported by in-depth biochemical/immunological studies. The aims of this research were: to evaluate cross-reactivity between lamb and beef; to evaluate the role of BSA and OSA as allergens in beef allergic children; and to evaluate cross-reactivity between BSA and OSA. METHODS: 16 children suffering from atopic dermatitis (AD), aged 12 months-8 8 years (mean age 2.61 +/- 1.93 years) were found skin prick test (SPT)--positive to bovine meat; all of them were also SPT-positive to ovine meat and to milk. After a period of restricted diet, the selected 16 children were recalled; 12 AD-free children (8 males and 14 females, aged 12 months-4.33 years (mean age 2.21 +/- 1.05 years) were evaluated by SPT and radioallergosorbent test (RAST) for the following allergens: bovine meat, ovine meat, BSA 1 mg/ml, OSA 1 mg/ml. Double-blind, placebo-controlled food challenge (DBPCFC) with bovine serum albumin (BSA) and ovine serum albumin (OSA) were performed. For SPT, the results were expressed in mm of wheal, and 3 mm was considered as the end point; correlation between wheal diameters was calculated by Spearman rank test. For DBPCFC, according to the Sampson's experimental procedure, BSA and OSA were given in pear juice (the dermal negative response to the pear juice was verified by fresh food SPT before starting the oral challenge test). The total dose administered to the children corresponded to the amount of albumin present in 180 g of calf or lamb meat (90 and 63 mg respectively, as calculated by Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SPS-PAGE). The administration of pear juice (containing placebo or albumin) and symptom evaluation were entrusted to medical people who did not know what the child received. RESULTS: All children tested SPT positive to bovine and ovine meat, and to BSA and OSA. Significant correlations were observed between the following diameters of wheal: BSA vs OSA (R = 0.846, p < 0.0001); ovine meat vs OSA (R = 0.769, p < 0.005); b.meat vs o.meat (R = 0.771, p < 0.005); and ovine meat vs BSA (R = 0.594, p < 0.043). In RAST, 6 of 12 children were positive to bovine meat, 3 to lamb meat, 4 to BSA and 3 to OSA. DBPCFC showed an immediate reaction to BSA or OSA in 2 and 3 children, respectively. One other child developed severe dyspnea, cough and asthma 3 hours after OSA challenge. CONCLUSIONS: BSA and OSA are important beef and lamb allergens; they share not only proteic sequences, but also allergenic properties. Clinical tolerance to BSA and OSA can be present in beef and lamb SPT-positive children.

Meat allergy: II--Effects of food processing and enzymatic digestion on the allergenicity of bovine and ovine meats.

OBJECTIVES: This study was designed to evaluate whether peptic treatment of BSA and OSA affects their allergenicity and to evaluate the effect of technological treatments of meat for infant feeding on the allergenicity of these proteins. SUBJECTS: Twelve children (8 males and 14 females) suffering from atopic dermatitis (AD), aged 12 months to 4.33 years (mean age 2.21 +/- 1.05 years). STUDY DESIGN AND METHODS: Children suffering from atopic dermatitis (AD), (AD), clinically reactive and SPT-positive to beef, underwent skin prick testing (SPT) and radioallergosorbent test (RAST) with BSA and OSA, before and after peptic treatment. They were tested also with commercially available homogenized bovine meat (HBM) and with freeze-dried bovine (FDBM) and ovine (FDOM) meats. Peptic digestion of BSA and OSA was carried out in a Dubnoff's water bath containing 0.05 mg/ml of pepsin. SPT and RAST were performed for 1 mg/ml of BSA and OSA digested 5 minutes, 2 hours and 4 hours with pepsin; homogenized bovine meat, and FDBM and FDOM. SPT results were expressed as diameters (in mm) of the wheal obtained after SPT; a diameter > or = 3 mm was considered as positive. RAST was considered positive for IgE values 5 > UI/ml. RESULTS: SPT to native BSA and OSA were positive in all patients. Only 2 of the 12 children were SPT-positive to HBM, FDBM, and FDOM. After digestion, SPTs and were positive as follows: for BSA, 4/12 after 5 minutes peptic treatment, 2/12 after 2 hours and 2/12 after 4 hours; for OSA, 3/12 after 5 minutes peptic treatment, none after 2 and 4 hours. None of RASTs was positive after peptic attack. CONCLUSIONS: Both proteolytic digestion and technological treatment reduced the allergenic potential of meat products.

Utility of Hydrogen and Methane Breath Tests in Combination with X-Ray Examination after a Barium Meal in the Diagnosis of Small Bowel Bacterial Overgrowth after Jejuno-Ileal Bypass for Morbid Obesity.

To study why the symptoms of abdominal bloating occurring in a number of patients after jejuno-ileal bypass for morbid obesity become resistant to antibiotics, we used a method which combined a hydrogen breath test after lactulose with an X-ray examination of the abdomen after barium. Ten operated patients with bloating symptoms resistant to antibiotics, ten operated patients without symptoms or with pre-existing symptoms, that had remitted after antibiotic treatment and ten nonoperated obese controls were investigated. There was a significant correlation between post-surgical symptoms persisting after antibiotics and the exhalation of large amounts of hydrogen of colonic origin (> 100 parts per million) after lactulose. Furthermore, symptomatic patients had high prevalence of colonic motility disorders (slow transit). In these patients, treatment with a prokinetic (cisapride 40 mg/kg/day for 10 days) reduced colonic transit time, colonic hydrogen production and bloating symptoms. Abdominal symptoms in these patients may therefore have other causes than small bowel bacterial overgrowth alone. All operated patients with persistent abdominal bloating should therefore be investigated before starting empirical treatment with antibiotics.

Intestinal Microflora Settlement in Patients with Jejunoileal Bypass for Morbid Obesity.

Intestinal microflora settlement was evaluated in this retrospective study of 49 patients with jejunoileal bypass who required reoperation. Colonic microflora was observed in the samples of the contents of the functioning jejunum and ileum but not in 55% of the samples from the middle of the excluded loop. Colonization of the excluded loop was not detected in patients without clinical signs of bacterial overgrowth but was significantly frequent (p < 0.01) in those with clinical signs (bloating, migratory arthralgias, rashes, skin lesions). However, positive excluded loop cultures were not always associated with clinical manifestations. No significant correlation was observed between bacteriology of the contents of the excluded loop and bypass results. The success of an intestinal bypass may depend not only on anatomic and functional adaptation to the new, surgically created conditions, but also to the attainment of microbiological equilibrium in the intestinal ecosystem.

Formaldehyde and hexamethylenetetramine as food additives: chemical interactions and toxicology.

Formaldehyde (FA) and hexamethylenetetramine (HMT) are used in cheese production to control gas-forming clostridia; FA also occurs naturally in some foods at levels of 1-20 mg/kg. The toxicology of FA and HMT are briefly discussed together with their reaction in foods. The most abundant end-product of FA in cheese is spinacine derived from the N-terminal histidine residue in gamma 2-casein. Acute and short term toxicological studies on spinacine enable a No Observed Effect Level of 300 mg/kg body weight/day to be determined, leading to an Acceptable Daily Intake (ADI) for man of 3 mg/kg body weight/day. From these data a Tolerance Level (TL) of 1800 mg spinacine/kg cheese can be derived, leading to a Safety Margin (SM) of 12.9. It is concluded that there is no appreciable health risk from consumption of cheese made using formaldehyde (Grana Padano) or hexamethylenetetramine (Provolone).

[Chronic use of glucomannan in the dietary treatment of severe obesity]. / Impiego cronico del glucomannano nel trattamento dietetico delle obesità severe.

Two groups of 25 severely obese patients underwent 3 months of hypocaloric diet therapy either alone or associated with a glucomannan-based fibrous diet supplement (approx. 4 g/die in 3 doses). The comparative analysis of the results obtained in both groups showed that the diet + glucomannan group had a more significant weight loss in relation to the fatty mass alone, an overall improvement in lipid status and carbohydrate tolerance, and a greater adherence to the diet in the absence of any relevant side effects. Due to the marked ability to satiate patients and the positive metabolic effects, glucomannan diet supplements have been found to be particularly efficacious and well tolerated even in the long-term treatment of severe obesity.

[Current world experience in the surgical treatment of gross obesity]. / L'esperienza mondiale attuale nel trattamento chirurgico della grande obesità.

Since 1954 the aim of surgical treatment of severe obesity has been to perfect a specific treatment capable of obtaining a massive, long-lasting and well tolerated loss of weight in severely obese subjects in which different and repeated attempts using conservative medicine have proved inefficacious or non-resolutive. During the course of almost 40 years, bariatric surgery has gradually evolved in the search for the "ideal" surgical treatment: for this purpose, operative methodologies and techniques have been proposed and experimented using differing physiopathological concepts and means of application. After a brief analysis of the history of bariatric surgery, there is a short summary of the most internationally widespread surgical methods and the most recent techniques now used for the surgical treatment of severe obesity based on the Authors' ten year experience of 321 intestinal bypasses (jejuno-ileal and biliointestinal), 110 horizontal gastroplasties and 23 vertical gastroplasties with a silastic ring. Intestinal bypass almost always allows sufficient weight loss to be achieved (85% of operated patients lose 80% of excess body weight) and the various postoperative problems of differing degrees of severity can be prevented by adequate replacement therapy and regular outpatient monitoring. Gastroplasties lead to a slightly smaller loss of weight (73% of excess body weight) within a shorter period of time, with fewer postoperative problems, but at the expense of a drastic and continual reduction in food intake. All patients operated require intense and long-term postoperative follow-up carried out by experts in order to achieve the desired results.

[Dental training of assistants in the operatory. 2]. / L'informazione odontoiatrica delle assistenti di studio. Nota II.

A multiple choice test concerning etiopathogenesis, prevention and therapy of caries and periodontal disease was presented to dental assistants during a meeting in May '91. Despite an adequate information about these subjects, an incomplete view of dental-periodontal health was noted. This is a reason to confirm the need of professional Schools, in order to improve the knowledge about dental health.