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Among the histogenic subtypes of melanoma, nodular melanoma (NM) is the major contributor for thicker and fatal melanomas and it has been associated with melanoma-specific death in thin tumours, highlighting an important subgroup of `aggressive thin' melanomas. This review provides a synthesis of the distinct characteristics of NM, with respect to epidemiology and risk factors, clinical presentation, histopathology, molecular and dermoscopic aspects, and screening practices. The real challenges are to find better biomarkers of aggressiveness and to know whether the control of such aggressive melanomas can be influenced by targeted interventions such as early detection, drug interventions and preventive strategies.

The 16th Annual Scientific Meeting of the Society for Neuro-Oncology in Conjunction with the AANS/CNS Section on Tumors, Orange County, California, USA, 17-20 November 2011. In Neuro-Oncology, 2011, v. 13 n. Suppl. 3, p. iii111, abstract no. ET-18

The electrodeposition of NiFe and CoFe onto rotating disk electrodes and into high aspect ratio features in 300 μm-thick photoresist was studied using electrolytes previously considered in the literature. The through-thickness uniformity of the plated features was characterized with reference to the rotating disk electrode results. Current efficiencies for various deposition conditions were also characterized. The composition of NiFe was more sensitive to mixing than CoFe on a rotating disk electrode. This sensitivity was reflected in the higher nonuniformity in general of the plated high aspect ratio NiFe features; a feature with an aspect ratio of three showed decreasing Fe content towards the feature bottom, with the Fe content at the bottom less than half that at the top. CoFe showed only slightly decreasing Fe content for the same aspect ratios. The composition of both alloys near the feature opening (where more mixing occurs) was consistent with that of deposits obtained from rotating disk electrodes at high rotation rates.

A process has been developed, using LIGA fabrication techniques, for the electrodeposition of a high strength, heat resistant Ni–Mn alloy to meet the requirements of a mechanical microsystem component. The electrolyte bath chemistry consists of Ni sulfamate to which a small amount of manganese chloride is added. The Mn content for the electrodeposited alloys of interest is generally equal to or less than about 1 wt%. It is shown that its co-deposition with Ni is insensitive to feature aspect ratio and therefore not limited by mass transport effects, permitting uniform alloy deposition. While plating of this alloy at a constant current density yields a high strength deposit, it also results in a highly stressed film that makes the fabrication of thick section deposits problematic.To counter this, a pulsed deposition scheme is employed to fabricate a nanostructured film consisting of alternating nm-thick regions of low stress, relatively soft Ni, and high strength, and highly stressed, NiMn alloy. This moderates the high plating stress of the NiMn alloy and enables the deposition of thick deposits. Yield strengths of over 800 MPa are achievable in the pulse-plated material, with good as-plated ductility (∼6%). The material loses only about 15% of its original strength after a one hour, 600 °C anneal, and no embrittlement is observed since no sulfur-bearing additives are employed. To the contrary, ductility measured as strain to failure is improved.

A discrepancy in the results of the potential dependence of the chemical etch rate of (100) Si in alkaline solutions has been investigated. In contrast to previous work at high temperature, the etch rate of p-type silicon is found to be constant in the range negative with respect to the open-circuit potential while the etch rate of the n-type semiconductor decreases markedly. In line with some previous suggestions, this difference is accounted for by differences in the potential distribution at the semiconductor/solution interface, as revealed by electrical impedance measurements under etching conditions. The potential dependence of the anodic current, which is attributed to electron injection from an intermediate of the chemical etching reaction, is also considered.

High precision 1H(e, e'p)pi0 measurements at Q2 = 0.126. (GeV/c)2 are reported, which allow the determination of quadrupole amplitudes in the gamma*N --> Delta transition; they simultaneously test the reliability of electroproduction models. The derived quadrupole-to-dipole (I = 3/2) amplitude ratios, RSM = (-6.5 +/- 0.2stat+sys+/-2.5mod)% and REM = 9-2.1 +/-0.2stat+sys +/-2.0mod)%, are dominated by model error. Previous RSM and REM results should be reconsidered after the model uncertainties associated with the method of their extraction are taken into account.

The ratio of the proton's elastic electromagnetic form factors was obtained by measuring the transverse and longitudinal polarizations of recoiling protons from the elastic scattering of polarized electrons with unpolarized protons. The ratio of the electric to magnetic form factor is proportional to the ratio of the transverse to longitudinal recoil polarizations. The ratio was measured over a range of four-momentum transfer squared between 0.5 and 3.5 GeV-squared. Simultaneous measurement of transverse and longitudinal polarizations in a polarimeter provides good control of the systematic uncertainty. The results for the ratio of the proton's electric to magnetic form factors show a systematic decrease with increasing four momentum squared, indicating for the first time a marked difference in the spatial distribution of charge and magnetization currents in the proton.

This study was undertaken to test the hypothesis that increased sympathetic vasomotor drive is responsible for cortisol-induced hypertension.Ten healthy male subjects on a fixed sodium diet (150 mmol/day) were randomized to five days of treatment with cortisol (200 mg/day) or placebo in a double-blind crossover study. On day 5 of each treatment, multi-unit muscle sympathetic activity was recorded from the common peroneal nerve. Resting muscle sympathetic activity (MSA) was measured in the recumbent position and stimulated MSA was measured in the final 20 sec of end-inspiratory capacity apnoea and end-expiratory apnoea and in the second minute of a cold pressor stimulus. A subgroup of six subjects also underwent identical MSA measurements following 5 days treatment with dexamethasone (3 mg/day).Cortisol, but not placebo, significantly increased systolic (115+/-2 vs 129+/-3 mmHg precortisol vs cortisol day 5, p0.001) and diastolic blood pressure (53+/-3 vs 61+/-3, p0.05). Resting MSA was significantly reduced by cortisol (23.9+/-2.3 to 5.0+/-2.0 bursts/min, placebo vs cortisol, p0.01). Cortisol significantly attenuated the increase in MSA observed at end-inspiratory apnoea (56.3+/-3.9 vs 35.4+/-6.6, p0.05) and end-expiratory apnoea (50.5+/-3.5 vs 26.3+/-6.2 bursts/min, n = 8, p0.05), and during the cold pressor response (55.0+/-12.7 vs 21.4+/-7.6, n = 5, p0.05). Dexamethasone significantly increased systolic blood pressure and suppressed resting and stimulated MSA. No changes in body weight, haematocrit or angiotensin II concentrations occurred during dexamethasone treatment.MSA is significantly suppressed by cortisol treatment. As suppression of MSA is also observed during treatment with the pure glucocorticoid dexamethasone, suppressed MSA cannot be attributed to increased plasma volume or to changes in angiotensin II concentration. We conclude that cortisol-induced hypertension is not due to increased muscle sympathetic vasomotor drive.

The mechanism of photocurrent-doubling reactions at ZnO single-crystal electrodes in aqueous formate, tartrate and methanol solutions has been reinvestigated. On the basis of steady-state photocurrent measurements in a wide range of light intensity it is concluded that, in the case of formate and tartrate, the electron-injecting species arises from a reaction between the current-doubling agent and oxygen, formed in the photoanodic decomposition of ZnO. This is not the case for methanol. These conclusions are supported by the results of electrical impedance and intensity-modulated photocurrent spectroscopy measurements.

The majority of esophagectomies in Western parts of the world are performed by a transthoracic approach reflecting the prevalence of adenocarcinoma of the lower esophagus or esophagogastric junction. Minimally invasive esophagectomy (MIE) has been reported in a variety of formats, but there are no series that directly compare totally minimally invasive thoracolaparoscopic 2 stage esophagectomy (MIE-2) with open Ivor Lewis (IVL). A prospective single-center cohort study of patients undergoing elective MIE-2 or IVL between January 2005 and November 2010 was performed. Short-term clinicopathologic outcomes were recorded using validated systems. One hundred and six patients (median age 66, range 36-85, 88 M : 18 F) underwent two-stage esophagectomy (53 MIE-2 and 53 IVL). Patient demographics (age, sex, body mass index, American Society of Anesthesiologists grade, tumor characteristics, neoadjuvant chemotherapy, and TNM stage) were comparable between the two groups. Outcomes for MIE-2 and IVL were comparable for anastomotic leak rates (5 [9%] vs. 2 [4%], P= 0.241), resection margin clearance (R0) (43 [81%] vs. 38 [72%], P= 0.253), median lymph node yield (19 vs. 18, P= 0.584), and median length of stay (12 [range 7-91] vs. 12 [range 7-101] days), respectively. Blood loss was significantly less for MIE-2 compared with IVL (median 300 [range 0-1250] mL vs. 400 [range 0-3000] mL, respectively, P= 0.021). MIE-2 in this series of selected patients supports its efficacy, when performed by an experienced minimally invasive surgical team. A well-designed multicenter trial addressing clinical effectiveness is now required.

The mechanism of the two-step reduction of the methylviologen cation radical (MV 2+ ) was studied at CdS, GaAs and InP single crystal electrodes. In aqueous solution the second step (MV +. →MV 0 ) gives rise to layer formation which is not observed in mixed ethanol/water solutions. This layer has interesting electrical properties. The reoxidation of MV 0 occurs by electron injection into the conduction band of all three semiconductors. The reoxidation of MV +. at InP is also a conduction band reaction and electroluminescence is observed with the p-type semiconductor. Electron injection from MV +. into the conduction band of GaAs is not observed while the kinetics of the reaction at CdS depend critically on the state of the electrode surface and on the nature of the electrolyte solution.

OBJECTIVE. This study monitors trends in place of death among persons with acquired immunodeficiency syndrome (AIDS) as a measure of health care usage patterns and terminal health care among persons infected with human immunodeficiency virus (HIV). METHODS. Sixteen health departments collected death certificates for 55,186 persons with AIDS whose deaths occurred through 1991. Place of death was categorized as hospital, residence, hospice or nursing home, and other. RESULTS. The percentage of AIDS deaths at hospital facilities decreased from 92% in 1983 to 57% in 1991. In 1988, 23% of deaths occurred at home or in hospices and nursing homes. This trend was more evident among men, Whites, and men who had sex with men; less so among persons with other modes of exposure; and not at all among injecting drug users and children with perinatally acquired AIDS. Place of death varied by geographic location, with the greatest percentage of hospital deaths in the Northeast (91%) and the greatest percentage of at-home deaths in the West (27%). CONCLUSIONS. The percentage of AIDS deaths at home or in hospices and nursing homes has increased since 1983. These trends may reflect changes in hospital use for end-stage HIV infection. Decreasing hospitalization and increasing outpatient services and home care will decrease costs and may allow HIV-infected persons improved social support.

Metal ions, such as Hg 2+ , Pb 2+ , Mn 2+ , Eu 3+ , and Tb 3+ , can show emission at anodic valve metal oxides in the presence of an oxidizing agent. The luminescence is characteristic of the ions and agrees well with the luminescence in crystalline solids. Various observations indicate that both the oxide and the electrolyte species play a decisive role in the occurrence of emission. Hence, the emission must take place at the oxide/solution interface. A tentative mechanism is proposed involving reaction steps well known in electroluminescence and electrogenerated chemiluminescence

The electric form factor of the neutron was determined from studies of the reaction ${}^{3}\stackrel{\ensuremath{\rightarrow}}{\mathrm{He}}(\stackrel{\ensuremath{\rightarrow}}{e},{e}^{\ensuremath{'}}n)pp$ in quasielastic kinematics in Hall A at Jefferson Lab. Longitudinally polarized electrons were scattered off a polarized target in which the nuclear polarization was oriented perpendicular to the momentum transfer. The scattered electrons were detected in a magnetic spectrometer in coincidence with neutrons that were registered in a large-solid-angle detector. More than doubling the ${Q}^{2}$ range over which it is known, we find ${G}_{E}^{n}=0.0236\ifmmode\pm\else\textpm\fi{}0.0017(\mathrm{stat})\ifmmode\pm\else\textpm\fi{}0.0026(\mathrm{syst})$, $0.0208\ifmmode\pm\else\textpm\fi{}0.0024\ifmmode\pm\else\textpm\fi{}0.0019$, and $0.0147\ifmmode\pm\else\textpm\fi{}0.0020\ifmmode\pm\else\textpm\fi{}0.0014$ for ${Q}^{2}=1.72$, 2.48, and $3.41\text{ }\text{ }{\mathrm{GeV}}^{2}$, respectively.

Laparoscopic surgery has undergone a rapid evolution since the first laparoscopic cholecystectomy of Erich Mühe in 1985. Many surgeons felt that further technological success would be related not only to increasing experience and skill of surgeons, but also technological advances which would enable surgeons to perform increasingly more difficult and complex tasks. Progress has been rapid for some, but broad acceptance by surgeons has been slow.

Hand-assisted laparoscopic surgery (HALS) has been sporadically described in the past to assist the surgeon during operations of complexity or when operations require specimen removal. The hand will offer the surgeon an advantage in terms of tactile feedback, exposure, retraction, or orientation so that it will enable him or her to operate with greater safety and efficiency. The fundamental pre-requisite for successful HALS is a reliable hand-assist device. We perform HALS for complex advanced laparoscopic surgery where it may save time, increase accuracy and improve safety. Additionally, this approach is considered for any operation that requires specimen removal, since an enlarged incision may be required. Early introduction of the hand may facilitate dissection and specimen removal.

Metal ions, such as Hg 2+ , Pb 2+ , Mn 2+ , Eu 3+ , and Tb 3+ , can show emission at anodic valve metal oxides in the presence of an oxidizing agent. The luminescence is characteristic of the ions and agrees well with the luminescence in crystalline solids. Various observations indicate that both the oxide and the electrolyte species play a decisive role in the occurrence of emission. Hence, the emission must take place at the oxide/solution interface. A tentative mechanism is proposed involving reaction steps well known in electroluminescence and electrogenerated chemiluminescence

The electric form factor of the neutron was determined from studies of the reaction 3He(e,e'n)pp in quasielastic kinematics in Hall A at Jefferson Lab. Longitudinally polarized electrons were scattered off a polarized target in which the nuclear polarization was oriented perpendicular to the momentum transfer. The scattered electrons were detected in a magnetic spectrometer in coincidence with neutrons that were registered in a large-solid-angle detector. More than doubling the Q2 range over which it is known, we find G(E)(n)=0.0236±0.0017(stat)±0.0026(syst), 0.0208±0.0024±0.0019, and 0.0147±0.0020±0.0014 for Q(2)=1.72, 2.48, and 3.41 GeV2, respectively.

Results obtained from electrical impedance spectroscopy at n-GaAs in the dark with Fe(CN)63-, ClO− and BrO− in alkaline solution indicate that the cathodic reduction current is due mainly to electron-hole recombination at the surface. The same conclusion also holds for the recombination of photo-generated holes at illuminated n-GaAs in indifferent electrolyte. Electroluminescence measurements showed that surface recombination with the hypohalites is more effective than with Fe(CN)63-. Quantum efficiency measurements at p-GaAs revealed that the second charge transfer step of the hypohalite reduction can involve either the capture of an electron by or the injection of a hole from a surface intermediate. This result leads to a slight revision of a mechanism previously proposed for the reduction of ClO− and BrO− at GaAs.

Objectives: Illicit drug taking in Australia, with its attendant social and medical consequences, is increasing and the effects extend to maternity hospitals where infants born to addicted mothers have more health problems in the neonatal period. The aims of this study were to evaluate (1) the patterns of illness of such infants and (2) the burden imposed on the neonatal department of a large tertiary maternity centre. Methodology: An audit was conducted of all Chemical Dependency Unit (CDU) mothers and babies delivered at the Royal Women's Hospital, Melbourne Australia during 1997. Data were compared with those from a concurrent control group of mothers and babies randomly generated from the hospital's obstetric database. Results: Ninety-six infants born to CDU mothers were compared with a control group of 200 infant/mother pairs. The majority of women in the CDU clinic were treated for narcotic addiction with methadone (90%) but most continued to use heroin during pregnancy (68%). Infants born to CDU mothers were significantly less mature and lighter than control infants. Fifty-three (55%) CDU infants required admission to the Special Care Nursery either because of neonatal abstinence syndrome (n = 29) or other medical reasons (n = 24). The median length of hospital stay was significantly longer in CDU compared with control infants (8 vs 3 days, P < 0.01). Conclusions: Infants born to drug dependent mothers have more neonatal problems requiring specialized medical and nursing expertise, compared with control infants. These infants are large consumers of scarce health resources.

The effects of various process parameters, including liner/seed deposition, electrodeposition process and chemistry, and CMP (chemical mechanical planarization), on the formation of void defects in 32 nm copper metallization was investigated using a KLA-Tencor brightfield defect detection system. Optimum process conditions were determined based on void defectivity levels.

We report a virtual Compton scattering study of the proton at low c.m. energies. We have determined the structure functions P(LL)-P(TT)/epsilon and P(LT), and the electric and magnetic generalized polarizabilities (GPs) alpha(E)(Q2) and beta(M)(Q2) at momentum transfer Q(2)=0.92 and 1.76 GeV2. The electric GP shows a strong falloff with Q2, and its global behavior does not follow a simple dipole form. The magnetic GP shows a rise and then a falloff; this can be interpreted as the dominance of a long-distance diamagnetic pion cloud at low Q2, compensated at higher Q2 by a paramagnetic contribution from piN intermediate states.

We have studied the quasielastic 3He(e,e(')p)2H reaction in perpendicular coplanar kinematics, with the energy and the momentum transferred by the electron fixed at 840 MeV and 1502 MeV/c, respectively. The 3He(e,e(')p)2H cross section was measured for missing momenta up to 1000 MeV/c, while the A(TL) asymmetry was extracted for missing momenta up to 660 MeV/c. For missing momenta up to 150 MeV/c, the cross section is described by variational calculations using modern 3He wave functions. For missing momenta from 150 to 750 MeV/c, strong final-state interaction effects are observed. Near 1000 MeV/c, the experimental cross section is more than an order of magnitude larger than predicted by available theories. The A(TL) asymmetry displays characteristic features of broken factorization with a structure that is similar to that generated by available models.

Spectrally resolved electroluminescence (EL) has been studied during anodic dissolution of p-InP, p-GaAs, and p-GaP electrodes in indifferent aqueous electrolyte solutions. The most efficient EL was found for p-InP whereas p-GaP showed no emission. The EL is attributed to radiative band-band recombination of holes with electrons excited from dissolution intermediates

We report a virtual Compton scattering study of the proton at low c.m. energies. We have determined the structure functions P(LL)-P(TT)/epsilon and P(LT), and the electric and magnetic generalized polarizabilities (GPs) alpha(E)(Q2) and beta(M)(Q2) at momentum transfer Q(2)=0.92 and 1.76 GeV2. The electric GP shows a strong falloff with Q2, and its global behavior does not follow a simple dipole form. The magnetic GP shows a rise and then a falloff; this can be interpreted as the dominance of a long-distance diamagnetic pion cloud at low Q2, compensated at higher Q2 by a paramagnetic contribution from piN intermediate states.

We report new measurements of the ratio of the electric form factor to the magnetic form factor of the neutron, ${G}_{E}^{n}/{G}_{M}^{n}$, obtained via recoil polarimetry from the quasielastic $^{2}\mathrm{H}(\stackrel{\ensuremath{\rightarrow}}{e},{e}^{\ensuremath{'}}\stackrel{\ensuremath{\rightarrow}}{n})^{1}\mathrm{H}$ reaction at ${Q}^{2}$ values of 0.45, 1.13, and $1.45\text{ }(\mathrm{G}\mathrm{e}\mathrm{V}/c{)}^{2}$ with relative statistical uncertainties of $7.6%$ and $8.4%$ at the two higher ${Q}^{2}$ points, which points have never been achieved in polarization measurements.

We report new measurements of the ratio of the electric form factor to the magnetic form factor of the neutron, G(n)(E)/G(n)(M), obtained via recoil polarimetry from the quasielastic 2H(e--,e(')n--)1H reaction at Q2 values of 0.45, 1.13, and 1.45 (GeV/c)(2) with relative statistical uncertainties of 7.6% and 8.4% at the two higher Q2 points, which points have never been achieved in polarization measurements.

The Alaska Native Tumor Registry includes data from 1969 to the present. This report provides incidence rates over the thirty year period, 1969 through 1998, and compares trends over time for Alaska Natives (AN) with those of US Whites and Blacks. To examine current rates, average annual age-adjusted incidence rates for AN for 1984-98 are compared with US Whites. Data from the registry document numerous differences in rates of occurrence of specific cancers compared to US Whites and Blacks. Studies of these differences may provide clues to the causes and risk factors for the cancers. Most importantly, these data show that although cancer was considered a rare disease in the Alaska Native population as recently as the mid-twentieth century, the incidence rate for all cancers combined among Alaska Natives is now as high as that of US Whites, and even higher in women. On the other hand, despite relative differences in rates, the most frequently diagnosed cancers among Alaska Natives are the same as US Whites. Cancers of the lung, colon/rectum, breast, and prostate are most frequently diagnosed among Alaska Natives and in the U.S. These four cancers comprise over 50% of all diagnosed invasive cancers. Cancer of the lung is almost entirely preventable by eradication of tobacco use. Screening and early detection have been proven to reduce mortality for cancers of the colon/rectum and breast. Primary and secondary prevention of these cancers could markedly improve morbidity and mortality.

The ratio of the electric and magnetic form factors of the proton G(E(p))/G(M(p)), which is an image of its charge and magnetization distributions, was measured at the Thomas Jefferson National Accelerator Facility (JLab) using the recoil polarization technique. The ratio of the form factors is directly proportional to the ratio of the transverse to longitudinal components of the polarization of the recoil proton in the elastic e(--)p---e(--)p reaction. The new data presented span the range 3.5Q(2)5.6 GeV(2) and are well described by a linear Q(2) fit. Also, the ratio sqrt[Q(2)] F(2(p))/F(1(p)) reaches a constant value above Q(2) = 2 GeV(2).

Hand-assisted laparoscopic surgery (HALS) was developed to bridge the gap between open surgery and advanced laparoscopic surgery. Advantages of the hand in the abdomen include tactile feedback, the ability to palpate, blunt dissection, organ retraction, control of bleeding, and rapid organ removal. There are 3 commercially available devices in the United States, as well as a fourth in Europe and a fifth in Japan. Uses for HALS include procedures requiring intact specimen removal, complex laparoscopic procedures, preventing open conversion, and overcoming a technical obstacle. HALS procedures, such as esophagectomy, gastrectomy, hepatectomy, pancreatectomy, splenectomy, bariatric surgery, colectomy, nephrectomy, hysterectomy, and aortobifemoral bypass, have all been reported in the literature. Improvement in instrumentation, specifically with newer generation devices, will allow HALS to become more popular. We advocate the use of HALS specifically for laparoscopic colectomy, laparoscopic splenectomy for massive splenomegaly, and for living-related donor nephrectomy.

High-precision 1H(e,e'p)pi(0) measurements at Q2 = 0.126 (GeV/c)2 are reported, which allow the determination of quadrupole amplitudes in the gamma*N--Delta transition; they simultaneously test the reliability of electroproduction models. The derived quadrupole-to-dipole ( I = 3/2) amplitude ratios, R(SM) = (-6.5+/-0.2(stat+sys)+/-2.5(mod))% and R(EM) = (-2.1+/-0.2(stat+sys)+/-2.0(mod))%, are dominated by model error. Previous R(SM) and R(EM) results should be reconsidered after the model uncertainties associated with the method of their extraction are taken into account.

We measured the cross section and response functions for the quasielastic 16O(e,e'p) reaction for missing energies 25or =E(m)or =120 MeV at missing momenta P(m)or =340 MeV/c. For 25E(m)50 MeV and P(m) approximately 60 MeV/c, the reaction is dominated by a single 1s(1/2) proton knockout. At larger P(m), the single-particle aspects are increasingly masked by more complicated processes. Calculations which include pion exchange currents, isobar currents, and short-range correlations account for the shape and the transversity, but for only half of the magnitude of the measured cross section.

Extraocular muscle weakness is the most common presenting sign of myasthenia gravis (MG). More than half of patients presenting with symptoms isolated to these muscles (OMG) develop generalized myasthenia gravis (GMG) over the course of their illness. No clinical, laboratory, or electrophysiological features are recognized that identify these high-risk patients. We have therefore assessed the ability of single-fiber electromyography (SFEMG) to predict the development of GMG in patients presenting with OMG. Thirty-nine consecutive patients presenting with OMG underwent SFEMG of the extensor digitorum communis muscle as well as a battery of other laboratory and imaging studies at the time of diagnosis. All patients were followed prospectively for a minimum of 24 months or until they developed GMG. Two patients were excluded, leaving 37 for assessment. Twenty remained with pure OMG for the entire follow-up period (mean, 55 months). Twenty-six of the 37 had abnormal SFEMG studies at presentation. Eleven of these remained with OMG and 15 developed GMG. Fifty-eight percent of patients with an abnormal SFEMG developed GMG, whereas 82% of those with a normal study remained with OMG. Thus, a normal SFEMG was associated with MG remaining restricted to the extraocular muscles. (P = 0.036, Fisher's exact test), but an abnormal SFEMG was not predictive of subsequent development of GMG.

The azimuthal, far field directivity of a scale fan model was measured in high resolution. The model is a 12 inch diameter rotor with 16 blades followed by 40 stator vanes. The tests were conducted at the nominal 100 percent speed corresponding to a tip speed of 905 ft/sec. Measurement of the radiated sound field, forward of the fan, was made in an anechoic chamber with an inflow control device and a baffle separating the aft and forward radiated interaction noise. The acoustic field was surveyed with a circular hoop array of 16 microphones which was moved to 14 axial stations. At each axial station the hoop was rotated in half-degree increments to take 736 points in the azimuthal angle. In addition to sound pressure level, the phase angle relative to a reference microphone was measured at each point. The sound pressure level is shown to vary in patterns by 10-15 dB especially for the fundamental tone but also for the first and second harmonic. A far field mode detection method has been developed and used with the data which determines the modes generated by the fan and which then interact to form the azimuthal directivity.

Many advanced laparoscopic cases remain technically difficult and are less widely accepted. To a great extent, advanced laparoscopic surgery is handicapped by the loss of a surgeon's tactile sense. The concept of introducing the surgeon's hand as an aid to minimally invasive surgery has been described. We report a new hand-assist device designed to allow the introduction of the surgeon's hand, wrist, and forearm through a small incision in the abdomen to assist laparoscopic surgery with pneumoperitoneum. Important factors in the hand-assist design are ease of use, reliable maintenance of pneumoperitoneum, and minimal hand/arm fatigue, which were met with this device.

1. The cyclic AMP phosphodiesterases (PDE) in guinea-pig peritoneal macrophages were isolated, partially characterized and their role in regulating the cyclic AMP content in intact cells evaluated. 2. Differential centrifugation of macrophage lysates revealed that approximately 90% of the PDE activity was membrane-bound and exclusively hydrolyzed cyclic AMP. This activity was not removed by KCl (200 mM) but was readily solubilized by the non-ionic detergent, Triton X-100 (1% v/v). Greater than 80% of the hydrolytic activity was suppressed by the PDE4 inhibitors, R-rolipram and nitraquazone with IC50s of 240 and 540 nM, respectively. 3. Anion-exchange chromatography of the total protein extracted from macrophages resolved two major peaks of cyclic AMP PDE activity that were insensitive to cyclic GMP (10 microM), calmodulin (50 units plus 2 mM CaCl2) and a PDE3 inhibitor, SKF 95654 (10 microM), but were markedly suppressed by RS-rolipram (10 microM). The two peaks of PDE activity were arbitrarily designated CPPDE4alpha and CPPDE4beta with respect to the order from which they were eluted from the column where the prefix, CP, refers to the species, Cavia porcellus. 4. The hydrolysis of cyclic AMP catalyzed by CPPDE4alpha and CPPDE4beta conformed to Michaelis-Menten kinetic behaviour with similar K(m)s (13.4 and 6.4 microM, respectively). 5. Thermal denaturation of membrane-bound PDE4 at 50 degrees C followed bi-exponential kinetics with t1/2 values of 1.5 and 54.7 min for the first and second components, respectively. In contrast, CPPDE4alpha and CPPDE4beta each decayed mono-exponentially with significantly different thermostabilities (t1/2 = 2.77 and 1.15 min, respectively). 6. Gel filtration of CPPDE4beta separated two peaks of rolipram-sensitive PDE activity. The main peak eluted at a volume indicative of a approximately 180 kDa protein but was preceded by a much larger form of the enzyme that had an estimated weight of 750 kDa. Size exclusion chromatography of CPPDE4alpha resolved a broad peak of activity with molecular weights spanning 50 to 200 kDa. 7. Of ten PDE inhibitors examined, none distinguished CPPDE4alpha from CPPDE4beta with respect to their IC50 values or their rank order of potency. RS-rolipram acted as a purely competitive inhibitor of cyclic AMP hydrolysis with K(i)s of 2 microM and 1.5 microM for CPPDE4alpha and CPPDE4beta, respectively. In contrast to the membrane-associated enzyme(s), R-rolipram and nitraquazone were 4 to 19 fold less potent as inhibitors of CPPDE4alpha and CPPDE4beta. 8. In intact macrophages, Ro 20-1724 and RS-rolipram potentiated isoprenaline-induced cyclic AMP accumulation under conditions where a PDE3 inhibitor, SKF 94120, was essentially inactive. 9. These data demonstrate that the predominant cyclic AMP hydrolyzing activity in guinea-pig macrophages is a PDE4. Moreover, thermostability studies and size exclusion chromatography indicates the possible expression of two intrinsic, membrane-associated isoenzymes which can regulate the cyclic AMP content in intact cells. The finding that soluble and particulate forms of the same enzyme exhibit different sensitivities to rolipram and nitraquazone implies that PDE4 can change conformation. Finally, the identification of multiple molecular weight species of CPPDE4 suggests that this enzyme(s) might form multimeric complexes of variable association states.

This study was designed to define the dose-response relationships for cortisol-induced hypertension in humans and to test the hypothesis that cortisol-induced hypertension is a consequence of classical mineralocorticoid actions using the mineralocorticoid antagonist spironolactone.In study 1, six normal men were given cortisol orally every 6 h for 5 days at doses of 40, 80 and 200 mg per day. In study 2, six normal men were given spironolactone at 400 mg/day for 6 days and cortisol at 80 mg/day for 5 days, commencing on the second day of spironolactone treatment.Systolic blood pressure increased significantly with cortisol at 80 and 200 but not 40 mg/day. There was no difference between 80 and 200 mg/day. Weight increases were seen at the two higher doses and serum potassium concentration fell with each dose. Spironolactone prevented the increase in body weight and the decrease in serum potassium but did not affect the increase in blood pressure produced by cortisol.Cortisol at 80 and 200 mg per day produces similar blood pressure and metabolic effects. Spironolactone blocked the mineralocorticoid effects of cortisol but not the blood pressure rise, suggesting that these mineralocorticoid effects are not responsible for cortisol-induced hypertension.

Five-year average annual age-adjusted cancer incidence rates for Alaska Natives (Eskimos, Indians, and Aleuts) for the most recent period (1989-1993) are compared to rates of 20 years earlier. Rates for all cancers combined increased 28 and 25% in men and women, respectively, during the 25-year interval. Increases were seen in men in cancers of the lung, prostate, and colon and in women for cancers of the lung, breast, and corpus uteri. Rates are also compared to data from the the National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) program for United States whites. Rates for all cancers combined in Alaska Native women are now similar to those of United States whites, whereas rates in Alaska Native men are lower than the United States, but only 10% lower. Significant site-specific differences previously reported between Alaska Natives and United States whites persist.