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The jugular vein catheterism (JVC) is adopted for blood access in patients with acute renal failure, in chronic renal failure and when patients show failure of traditional vascular access. The technique of catheter insertion in the jugular vein is quick and easy. Usually correct catheter positioning, before starting the dialytic procedure, is controlled by chest X-ray or by intra-cavitary electrocardiogram. The aim of this work is to evaluate the feasibility of the real-time ultrasound guidance to control the correct positioning of the catheter instead of the usual chest X-ray control. We have studied 158 patients with JVC insertion before the hemodialytic procedure; 54 patients have undergone both ultrasound and a chest X-ray control while 104 were only submitted to ultrasound control. The ultrasound procedure includes an under xifoid scanning, with a convex 3.5 Mhz drill to evaluate the four heart cavities. When the right atrium is identified a second operator rapidly infuses in the venous catheter 15 ml of physiological solution thus creating a blood turbolence easily observed in real time as a light jet inside the atrium. This turbolence appears to be the main evidence for good catheter positioning and we were able to show the light jet in 156 (98%) patients. All light jet positive patients were submitted to the hemodialytic procedure without any complications during and after dialysis. We concluded that the intraoperative ultrasound control technique is an alternative to the chest X-ray evaluation because it offers the possibility for safe intraoperative immediate control thus reducing the total costs of the procedure.

We found, by circular dichroism and Raman spectroscopy measurements, that the secondary structure of the native ovalbumin and of its heat-stable form, called S-ovalbumin, is a probe of the structural differences between the two proteins. Small angle X-ray scattering and circular dichroism measurements performed on the two proteins under denaturing conditions, with different concentrations of guanidine hydrochloride, show the changes of the tertiary and secondary structure and a different pathway in the unfolding process. These experimental data confirm that the conversion of native ovalbumin into S-ovalbumin is irreversible and reveal that the response of the two proteins to the same chemical environment is different

Reaction of the anthracycline, antitumor drugs adriamycin and daunomycin with the self-complementary DNA oligonucleotide GCGCGCGC, (GC)4, in the presence of the reducing agent dithiothreitol, the oxidizing agent hydrogen peroxide, or the alkylating agent formaldehyde gives a similar mixture of DNA−drug adducts. Negative ion electrospray mass spectra indicate that adduct formation involves coupling of the DNA to the anthracycline via a methylene group and that the major adduct is duplex DNA containing two molecules of anthracycline, each bound to a separate strand of the DNA via a methylene group. The source of the methylene group is formaldehyde. A molecular structure with each anthracycline intercalated at a 5‘-CpG-3‘ site and covalently bound from its 3‘-amino group to a 2-amino group of a 2‘-deoxyguanosine nucleotide is proposed based upon spectral data and a relevant crystal structure. The reaction of (GC)4 with the anthracyclines and formaldehyde forms an equilibrium mixture with DNA−drug adducts which is shifted toward free DNA by dilution. The results suggest a pathway to the inhibition of transcription by reductively activated adriamycin and daunomycin. Reductive activation in the presence of oxygen yields hydrogen peroxide; hydrogen peroxide oxidizes constituents in the reaction mixture to formaldehyde; and formaldehyde couples the drug to DNA. In this regard, hydrogen peroxide reacts with adriamycin via Baeyer−Villiger reactions at the 13-position to yield 2, 3, and formaldehyde. Formaldehyde also results from hydrogen peroxide oxidation of Tris [tris(hydroxymethyl)aminomethane] present in transcription buffer and spermine, a polyamine commonly associated with DNA in vivo, presumably via the Fenton reaction.

The reaction of the antitumor drugs adriamycin and daunomycin with the self-complementary DNA oligonucleotide (GC)4 to generate DNA−drug adducts was investigated as a function of redox reaction conditions. The redox systems dithiothreitol (DTT)/Fe(III) and xanthine oxidase/NADH both gave the same distribution of four DNA−anthracycline adducts. In each of these adducts the anthracycline is bonded via a methylene linkage between the 3‘-amino group of the drug and the 2-amino group of a deoxyguanosine of the DNA. The methylene linkage results from reaction of the drug and DNA with in situ-generated formaldehyde via Schiff base chemistry [Taatjes, D. J., Gaudiano, G., Resing, K., and Koch, T. H. (1997) J. Med. Chem. 40, 1276−1286]. Formaldehyde production is promoted by iron, inhibited by metal-chelating agents, and does not require drug. Iron enhances formaldehyde production by a factor of 30, EDTA inhibits its formation by a factor of 2, and Desferal inhibits its formation by a factor of more than 20. Hydrogen peroxide accumulates in significant quantities only with xanthine oxidase/NADH in the presence of Desferal. The results are explained in terms of Fenton oxidation of Tris buffer to formaldehyde. Biological reagents also cause DNA−drug adduct formation; reduction of ferric ion with glutathione in phosphate buffer in the presence of spermine produced the same DNA−drug adducts. The observations are discussed in terms of cytotoxicity resulting from iron chelated to adriamycin catalyzing in vivo production of formaldehyde which links adriamycin to DNA and tumor cell resistance resulting from factors which decrease formaldehyde.

This article described neural network models for adaptive control of arm movement trajectories during visually guided reaching and, more generally, a framework for unsupervised real-time error-based learning. The models clarify how a child, or untrained robot, can learn to reach for objects that it sees. Piaget has provided basic insights with his concept of circular reaction:As an infant makes internally generated movements of its hand, the eyes automatically follow this motion. A transformation is learned between the visual representation of hand position and the motor representation of hand position. Learning of this transformation eventually enables the child to accurately reach for visually detected targets. It has been shown how the eye movement system can use visual error signals to correct movement parameters via cerebellar learning. Here it is shown how endogenously generated arm movements lead to adaptive tuning of arm control parameters. These movements also activate the target position representations that are used to learn the visuo-motor transformation that controls visually guided reaching. The AVITE model presented here is an adaptive neural circuit based on the Vector Integration to Endpoint (VITE) model for arm and speech trajectory generation of Bullock and Grossberg. In the VITE model, a Target Position Command (TPC) represents the location of the desired target. The Present Position Command (PPC) encodes the present hand-arm configuration. The Difference Vector (DV) population continuously computes the difference between the PPC and TPC. A speed-controlling GO signal multiplies DV output. The PPC integrates the (DV) · (GO) product and generates an outflw command to the arm. Integration at the PPC continues at a rate dependent on GO signal size until the DV reaches zero, at which time the PPC equals the TPC. The AVITE model explains how self-consistent TPC and PPC coordinates are autonomously generated and learned. Learning of AVITE parameters is regulated by activation of a self-regulating Endogenous Random Generator (ERG) of training vectors. Each vector is integrated at the PPC, giving rise to a movement command. The generation of each vector induces a complementary postural phase during which ERG output stops and learning occurs. Then a new vector is generated and the cycle is repeated. This cyclic, biphasic behavior is controlled by a specialized gated dipole circuit. ERG output autonomously stops in such a way that, across trials, a broad sample of workspace target positions is generated. When the ERG shuts off, a modulator gate opens, copying the PPC into the TPC. Learning of a transformation from TPC to PPC occurs using the DV as an error signal that is zeroed due to learning. This learning scheme is called a Vector Associative Map, or VAM. The VAM model is a general-purpose device for autonomous real-time-error based learning and performance of associative maps. The DV stage serves the dual function of reading out new TPCs during performance and reading in new adaptive weights during learning, without a disruption of real-time operation. VAMs thus provide an on-line unsupervised alternative to the off-line properties of supervised error-correction learning algorithms. VAMs and VAM cascades for learning motor-to-motor and spatial-to-motor maps are described. VAM models and Adaptive Resonance Theory (ART) models exhibit complementary matching, learning, and performance properties that together provide a foundation for designing a total sensory-cognitive and cognitive-motor autonomous system.

The determination of dialysis adequacy is difficult and definitions are in a state of flux (Lindsay). In fact, after fifteen years from the introduction of urea kinetics into clinical practice, nephrologists still do not agree on recognizing the real utility of it. Gotch and Sargent in their mechanistic analysis of the NCDS indicated that the dose of small molecules removal could be defined by Kt/V urea. The results of the NCDS were depicted in a three-variable plot in which six domains could be seen. Several reports have documented malnutrition as being frequently present in patients on maintenance hemodialysis. It is generally accepted that a suboptimal nutritional status is associated with an increased morbidity and may adversely affect rehabilitation and the quality of life. In 1989 Lindsay et al showed that low levels of Kt/V corresponded with low levels of nPCR and found a direct correlation between the two parameters. On this basis, they suggested the hypothesis of nPCR dependence on Kt/V. The Authors showed a good correlation (r=0.73) between nPCR and Kt/V in 55 patients. This work aims to evaluate the correlation between Kt/V and nPCR, real age and dialytic age in a dialytic population in Southern Italy, during a long period of observation (six years, follow up 2,692 months). One hundred and thirty-four patients were studied in six years of observation. Follow up: 2692 months. Twenty-six patients died during the observation period. The simple regression analysis of nPCR vs. Kt/V, real age and dialytic age was performed in 63 anuric patients. nPCR showed a statistical difference (p<0.01) versus reall age, but no difference versus dialytic age and Kt/V. Our research data show that increasing Kt/V administration does not modify the nPCR of patients with initial and steady low protein intake over a medium time of observation. The same happens in patients with initial and steady high protein intake, when decreasing Kt/V administration in a short period of observation. We confirm that nPCR and Kt/V do not show any mathematical correlation in short and medium times of observation. It is also stressed by the simple regression analysis of data for a selected population of anuric uremics on dialysis thrice weekly for long observation times (between three and six years). Variance analysis (in 8 patients who had used all the membranes) showed differences between Kt/V and dialytic age, but not nPCR and real age. Kt/V and biocompatibility do not appear to be correlated directly with nPCR, because other factors are important in determining the general well-being in uremic patients. Such factors have to be considered when prescribing the dialytic “dose” and in clinically evaluating a uremic patient.

IN RECENT YEARS the spectrum of disease patterns produced by intestinal ischemia has been recognized.1,2 Abdominal symptoms, both of an acute and chronic nature, may be due to vascular insufficiency of the mesenteric vessels.When the large bowel is affected, the syndrome of reversible vascular occlusion of the colon may occur.3 All descriptions of this syndrome stress the diagnostic roentgen features and allude to the possibility of their confusion with colon carcinoma. In the series of cases reported, only two such instances are noted.2,3The following patient with reversible vascular occlusion presented with symptoms and radiologic evidence suggesting carcinoma of the transverse colon. The case is reported to emphasize the protean manifestations of vascular disease. It provides additional evidence that vascular insufficiency must be considered in the differential diagnosis of carcinoma of the colon. REPORT OF A CASE A 72-year-old Puerto Rican woman entered the hospital because

Explores how U.S. military lawyers challenged military commissions to defend detainees at Guantanamo Bay Naval Station, Cuba. Resignation of Air Force prosecutors; Problems with the military commission system established by the Defense Department; Example of the prosecutor advising the appointing authority on rulings.

Focuses on a death sentence given to U.S. Senior Airman Andrew Witt for the murder of Senior Airman Andy Schliepsiek and his wife, Jamie, as of October 2005. Facts of the case; Steps to be taken in carrying out the sentence imposed on Witt; Background of Witt.

Focuses on the claims of Alexis Witt, wife of the late U.S. Air Force Staff Sergeant Dean Witt, against the David Grant Medical Center at Travis Air Force Base in California for negligent postoperative care and supervision of hospital personnel that led to the death of her husband following a successful appendectomy. Provisions of the Federal Tort Claims Act which exempts the government from being liable to injuries sustained by military members while on active duty; Background on the alleged medical malpractice of the hospital; Details of the case.

Reports on the decision of the U.S. Air Force to remove organizational patches in the utility uniforms of airmen to be released in fiscal 2007. Reasons behind the decision; Reaction of airmen to the removal of patches according to an interview conducted by the "Air Force Times" periodical; Implications of the removal of the patches on the history of Air Force.

Reports on the protest of U.S. Air Force Colonel Judith Varnau against the travel card contract with Bank of America. Reason for opposing the credit card required by the government; Questions raised by Varnau about the credit card; Response of Bank of America to Varnau's questions.

Discusses the leadership crisis facing the U.S. Air Force in 2005. Information on the retirement of several Air Force leaders; Actions taken by the administration of President George W. Bush to address the crisis; Conflict between the Congress and the Department of Defense concerning military nominations.

Deals with the Air Education and Training Command ban in the U.S. Air Force. Effort of the U.S. military to reduce tobacco use; Restriction on smoking beyond basic military training; Application of the rule for nonprior service technical training students.

Reports on the court-martial given to Staff Sergeant Jennifer Jones who allegedly had a relationship with a senior airman who was her student at Sheppard Air Force Base in Texas. Comparison of Jones' case with that of Major General Thomas Fiscus, who had engaged in several unprofessional relationships outside his marriage; Charges against Jones; Concern on the fairness of military justice in the Air Force.

Provides information on an order for Thomas Fiscus, a former U.S. judge advocate general, to retire in the permanent grade of colonel, a two-grade demotion, following his nonjudicial punishment on several charges including conduct unbecoming an officer and unprofessional relationships, as of January 2005. Statement issued by Fiscus regarding the charges; Background on an investigation into the charges; Views of David H. Robertson, lawyer of Fiscus, on the punishment that his client received.

Deals with the work of the missile field airmen of the U.S. Air Force. Estimated number of days spend by missile field airmen in the job annually; Comments from Evan J. Hoapili, commander of the 90th Space Wing at F. E. Warren Air Base; Details of the work of missile field airmen; Difficulties experienced by the airmen.

Reports on the string of tragedies such as the four suicides and two slayings that took place at the Robins Air Force Base in Georgia. Reputation of the 116th Air Control Wing; Common denominator among the self-inflicted deaths; Efforts of the 116th Air Control Wing to respond to the tragedies.

Discusses the changes in the U.S. Air Force combat air patrols since the September 11, 2001 terrorist attack in the country. Views of Technician Sergeant Chad Campbell concerning the days before the attack; Thought that came to the mind of Campbell when he heard the alert horn on September 11; Estimated number of flights in support for the homeland defense of aerial tankers and early-warning aircraft since September 11 according to North American Aerospace Defense Command.

Discusses the efforts of U.S. military leaders in solving sex crimes occurring in the U.S. Air Force Academy as of March 22, 2004. Message of Air Force Secretary James Roche on the issue; Details of a sexual-assault study initiated by Pacific Air Forces Commander General William J. Begert at the Pacific Air Force (PacAF) Academy; Efforts of military leaders and departments in reassessing sexual-assault response programs in U.S. air bases; Statistics on the number of sex crimes found by the PacAF team.

Provides information on the herb Salvia divinorum which is known to have hallucinogenic effects. Description of its physiological effect; Status of the herb in the U.S. military; Salvia abuse levels among teenagers; Predicament posed by the herb to the military.

We retrospectively evaluated 262 individuals with intermediate- or high-risk prostate cancer. Among patients at high risk, we identified a subgroup of individuals harboring very high-risk (VHR) disease. Considering men with VHR disease (n = 28), 11C-choline positron emission tomography/computed tomography versus contrast-enhanced computed tomography had sensitivity and specificity of 71% and 92% versus 25% and 79%, respectively.

Introduction: