What physicians do in case of a failure of the pace-sense part of a defibrillation lead : Survey in Germany, Austria and Switzerland.

BACKGROUND: The possible treatment strategies for defects of the pace-sense (P/S) part of a defibrillation lead are either implantation of a new high-voltage (HV)-P/S lead, with or without extraction of the malfunctioning lead, or implantation of a P/S lead. METHODS: We conducted a Web-based survey across cardiac implantable electronic device (CIED) centers to investigate their procedural practice and decision-making process in cases of failure of the P/S portion of defibrillation leads. In particular, we focused on the question of whether the integrity of the HV circuit is confirmed by a test shock before decision-making. The questionnaire included 14 questions and was sent to 951 German, 341 Austrian, and 120 Swiss centers. RESULTS: The survey was completed by 183 of the 1412 centers surveyed (12.7% response rate). Most centers (90.2%) do not conduct a test shock to confirm the integrity of the HV circuit before decision-making. Procedural practice in lead management varies depending on the presentation of lead failure and whether the center applies a test shock. In centers that do not conduct a test shock, the majority (69.9%) implant a new HV-P/S lead. Most centers (61.7%) that test the integrity of the HV system implant a P/S lead. The majority of centers favor DF-4 connectors (74.1%) over DF-1 connectors (25.9%) at first CIED implantation. CONCLUSION: Either implanting a new HV-P/S lead or placing an additional P/S lead are selected strategies if the implantable cardioverter-defibrillator lead failure is localized to the P/S portion. However, conducting a test shock to confirm the integrity of the HV component is rarely performed.

Virial coefficients of the uniform electron gas from path-integral Monte Carlo simulations.

The properties of plasmas in the low-density limit are described by virial expansions. Analytical expressions are known from Green's function approaches only for the first three virial coefficients. Accurate path-integral Monte Carlo (PIMC) simulations have recently been performed for the uniform electron gas, allowing the virial expansions to be analyzed and interpolation formulas to be derived. The exact expression for the second virial coefficient is used to test the accuracy of the PIMC simulations and the range of validity of the interpolation formula of Groth et al. [Phys. Rev. Lett. 119, 135001 (2017)0031-900710.1103/PhysRevLett.119.135001], and we discuss the fourth virial coefficient, which is not exactly known yet. Combining PIMC simulations with benchmarks from exact virial expansion results would allow us to obtain more accurate representations of the equation of state for parameter ranges of conditions which are of interest, e.g., for helioseismology.

Astrophysics: quark matter in compact stars?

In a theoretical interpretation of observational data from the neutron star EXO 0748-676, Ozel concludes that quark matter probably does not exist in the centre of neutron stars. However, this conclusion is based on a limited set of possible equations of state for quark matter. Here we compare Ozel's observational limits with predictions based on a more comprehensive set of proposed quark-matter equations of state from the literature, and conclude that the presence of quark matter in EXO 0748-676 is not ruled out.

Symmetry energy of dilute warm nuclear matter.

The symmetry energy of nuclear matter is a fundamental ingredient in the investigation of exotic nuclei, heavy-ion collisions, and astrophysical phenomena. New data from heavy-ion collisions can be used to extract the free symmetry energy and the internal symmetry energy at subsaturation densities and temperatures below 10 MeV. Conventional theoretical calculations of the symmetry energy based on mean-field approaches fail to give the correct low-temperature, low-density limit that is governed by correlations, in particular, by the appearance of bound states. A recently developed quantum-statistical approach that takes the formation of clusters into account predicts symmetry energies that are in very good agreement with the experimental data. A consistent description of the symmetry energy is given that joins the correct low-density limit with quasiparticle approaches valid near the saturation density.

Long-term growth hormone (GH) replacement of adult GH deficiency (GHD) benefits the heart.

OBJECTIVE: Growth hormone (GH) deficiency is related to increased cardiovascular mortality. We studied clinical status, concentration of amino-terminal-pro B-type natriuretic-peptide (NT-proBNP) and echocardiographic parameters during long-term GH replacement (GH-R). METHODS: Fifty-one patients (29 females), 45.9 ± 11.3 years (mean ± s.d.), median follow-up 36.2 months, echocardiography and laboratory determinations initially and at 12-months intervals. RESULTS: At the last follow-up (last observation carried forward) (LFU (LOCF)) insulin-like growth-factor-1 standard deviation score (IGF-1 SDS) was ±1 in 92% of the patients. The median NT-proBNP declined significantly and stabilized (-40.5%) at LFU (LOCF) due to patients with a basal NT-proBNP >125 ng/L (indicative of heart failure). The basal NT-proBNP and the final IGF-1 SDS were significant predictors of the NT-proBNP at LFU (LOCF). Initially left ventricular enddiastolic diameter (LVEDD), left ventricular posterior wall diameter (LVPWD) and ejection fraction (EF) were normal, while interventricular septum diameter (IVSD) and left ventricular mass index (LVMi) were slightly increased. LVPWD and IVSD had significantly declined by year three. The LVMi was moderately to severely abnormal in 37.3 and 52.0% of patients initially and at LFU (LOCF). At LFU (LOCF) LVMi and IGF-1 were significantly correlated in the 14 male patients of this subgroup. CONCLUSION: Long-term GH-R of GHD positively affected ISVD and LVPWD. In a subgroup of patients with severe GHD, LVMi increased concomitantly to the decline in NT-proBNP and this was positively correlated to the final IGF-1 concentration. Whether this observation indicates a positive development in a structurally altered heart muscle (reversal of adverse remodelling) or poses a future risk for heart failure needs further follow-up.

Analysis of the promoter of the human prostatic acid phosphatase gene.

From the analysis of two overlapping cosmid clones prepared from human genomic DNA libraries, a contig of 44 kb containing a 5' portion of the PAP gene and 17 kb of the upstream region was established. It was characterized by restriction mapping and sequence analysis of 2.5 kb upstream of the initiation codon. Two major transcription initiation sites were found to be located around 56 and 91 bp upstream of the initiation codon, as determined by nuclease S1 and primer extension mapping. Expression of the PAP gene was measured by Northern blots in the androgen responsive LNCaP cell line. It was found to be induced 2-3-fold by the addition of the synthetic androgen mibolerone to the cells. The induced mRNA levels were approx. 10-times lower than those for the prostate-specific antigen (PSA) in LNCaP cells.

Transcriptional and posttranscriptional regulation of human androgen receptor expression by androgen.

Autoregulation is a control mechanism common to several proteins of the steroid/thyroid hormone receptor superfamily. In this work, the effect of androgens and antiandrogens on the expression of the human androgen receptor (hAR) in prostate and breast cancer cell lines was studied. Northern blot analysis revealed a decrease in hAR steady state RNA levels in LNCaP cells by 3.3 nM of the synthetic androgen mibolerone. Maximal down-regulation of hAR RNA to 30% of control levels occurred 48 h after hormone addition. T47D breast cancer cells showed a similar effect with mibolerone, while hAR expression in normal skin fibroblasts did not respond to androgen treatment. As shown by nuclease S1 analysis, hAR transcripts initiate at three principal start sites, all of which are equally sensitive to androgen. Steroidal as well as nonsteroidal antiandrogens were capable of partially antagonizing androgen-mediated hAR RNA down-regulation in LNCaP and T47D cells, while not exerting a significant effect when administered alone. While hAR RNA stability was increased by hormone, nuclear run-on analysis revealed a 4-fold reduction of hAR gene transcription 96 h after androgen treatment. Although decreased hAR RNA levels did not coincide with a parallel decrease in AR protein levels, analysis of androgen-inducible reporter constructs demonstrated that prolonged androgen administration to cells results in a progressively impaired sensitivity of the intracellular androgen response mechanism. These results show that prolonged androgen exposure leads, besides its effect on hAR RNA levels, to functional inactivation of the AR. Thus, in vivo, posttranslational control of AR activity appears to be a novel mechanism of negative autoregulation of androgen effects on gene expression.

Dose-dependent growth hormone, prolactin and cortisol stimulation after i.v. administration of desimipramine in human subjects.

In previous studies it was shown that the tricyclic antidepressant desimipramine (DMI) had different stimulatory effects on growth hormone (GH), prolactin (PRL), ACTH and cortisol secretion in healthy subjects, depending on the mode of administration. The present study examined the effects following i.v. administration of placebo and DMI (5, 15, 25, 50 and 75 mg) on GH, PRL and cortisol secretion in male subjects (n = 6). This primarily noradrenergic and secondarily serotonergic reuptake-inhibiting substance was found to stimulate the secretion of GH, PRL and cortisol in a dose-dependent manner. Compared to placebo, significant increases occurred in GH (p less than 0.05) and in PRL (p less than 0.05) from a dose of DMI 25 mg on, and in cortisol (p less than 0.05) from 15 mg on. The results indicate that, in addition to the dose, the method of administration influenced the effects of DMI on the three hormones.

Effect of receptor blockers (methysergide, propranolol, phentolamine, yohimbine and prazosin) on desimipramine-induced pituitary hormone stimulation in humans--I. Growth hormone.

In this report the effects of various receptor blockers on desimipramine (DMI)-induced growth hormone (GH) secretion in healthy male subjects are presented. Each trial consisted of two administrations: one of DMI i.v. alone and one of DMI i.v. in combination with the respective receptor blocker: methysergide (serotonin (5-HT) receptor blocker), propranolol (beta receptor blocker), phentolamine (alpha-1/alpha-2 receptor blocker), yohimbine (alpha-2 greater than alpha-1 receptor blocker), and prazosin (alpha-1 receptor blocker). DMI-induced GH stimulation was not significantly different after DMI i.v. alone (n = 12) than after three days' pretreatment with 12 mg methysergide p.o. in another group of subjects (n = 12). Following combined administration of DMI and propranolol (15 mg i.v.), GH secretion was significantly increased by 25 mg DMI (p less than 0.05) and 50 mg DMI (incomplete block design, n = 18). GH secretion was significantly lower (p less than 0.01) after DMI in combination with 60 mg phentolamine i.v. compared to that after administration of DMI alone in the same group (n = 12). Following 10 mg yohimbine i.v. in combination with DMI (n = 6), the DMI-induced GH increase was also significantly less (p less than 0.05) than that after DMI alone. The DMI-induced GH increase following DMI plus 1 mg prazosin p.o. (n = 12) was comparable to that after DMI alone. The results indicate that the GH-stimulating effect of DMI is primarily related to the ability of DMI to inhibit noradrenaline (NA) reuptake. Should serotonergic receptors be involved in the DMI-induced GH secretion at all, they transmit a positive stimulus. The alpha-1 receptors are most likely not (or not essentially) involved, whereas alpha-2 receptors affect the DMI-induced secretion positively, and beta receptors have an inhibitory effect.

Normal TMJ bony relationships in centric occlusion.

In a preliminary investigation, condyle-temporal bone spatial relationships were determined quantitatively in 50 asymptomatic TMJs (25 subjects) by making area measurements of the posterior and anterior portions of the joint spaces. For both right and left sides, the numerical expression of the joint relationship indicated that the condyle is normally centered in the joint to a very high degree. Standard deviations around the mean joint relationship values were large, however, which suggests that the posteroanterior variation of condyle positions in asymptomatic TMJs is greater than commonly thought. In addition, there was only mild correlation between individual joint relationships on right and left sides.

A method for quantitatively determining temporomandibular joint bony relationships.

The spatial relationship of the mandibular condyle to the temporal component of the TMJ is determined quantitatively from lateral tomograms using a new method of measuring specific areas of the joint space. Condyle position along the posteroanterior axis of the joint is expressed as a ratio of the posterior joint space area divided by the anterior joint space area (the P/A ratio). A description of the method, as used in a clinical evaluation of 50 asymptomatic tMJs, and a statistical evaluation of the method's reproducibility and accuracy are given. The method was found to have both high reproducibility and high accuracy.

Arthorgraphy of the temporomandibular joint: review of current status.

Arthrography of the temporomandibular joint is used principally in cases of pain and dysfunction, specifically clicking, popping, or locking joints. The procedure is effective and safe but technically difficult to perform.

Oral radiographic changes in patients with progressive systemic sclerosis (scleroderma).

Intraoral and panoramic radiographs were made of 35 patients with progressive systemic sclerosis. Of those patients, 13 (37%) were found to have abnormally thickened periodontal ligament spaces. Six of the 35 demonstrated mild to significant resorption of the posterior mandibular angle. Three patients, including two showing angle resorption also had some degree of coronoid process destruction. All patients with this disease should receive initial and follow-up panoramic radiographic examinations to determine any osseous changes.

Pair production and optical lasers.

Electron-positron pair creation in a standing wave is explored using a parameter-free quantum kinetic equation. Field strengths and frequencies corresponding to modern optical lasers induce a material polarization of the QED vacuum, which may be characterized as a plasma of e+e- quasiparticle pairs with a density of approximately 10(20) cm-3. The plasma vanishes almost completely when the laser field is zero, leaving a very small residual pair density n(r) which is the true manifestation of vacuum decay. The average pair density per period is proportional to the laser intensity but independent of the frequency nu. The density of residual pairs also grows with laser intensity but n(r) proportional to nu(2). With optical lasers at the forefront of the current generation, these dynamical QED vacuum effects can plausibly generate 5-10 observable two-photon annihilation events per laser pulse.

[Course and outcome of vocational training in young adults]. / Verlauf und Erfolg der beruflichen Ausbildung im Jugendalter.

Presented are the findings of vocational training data analysis concerning the 91,241 disabled young people who had entered vocational training in the period 1982-87 carried by the Federal Employment Institute within the scope of "Anordnung Rehabilitation" (AReha). 77% of the young rehabilitees successfully concluded their vocational training at the first attempt; 22% dropped out, and 2% failed at the exams. Of those who had dropped out prematurely, some 39% participated in other types of vocational rehabilitation measures; no data are contained in the statistics concerning the whereabouts of the remainder. The majority of the young people, i.e. 77%, underwent vocational training in a recognized training occupation, the others in line with section 48 BBiG (vocational education act) or section 42 b HwO (handicrafts ordinance) to reduced requirements. 61% of the training measures were industrial ones, 23% provided in a vocational training centre, and the remaining 16% in some other non-industrial rehabilitation facility. The greatest single population among the young rehabilitees were those with learning disabilities, with a share of 63%. The Federal Employment Institute's statistics containing no data beyond the termination of training, information relative to vocational integration after training completion could only be gained on the basis of other, empirical investigations.