Magnetic Resonance Imaging and Angiography for the Assessment of Coarctation of the Aorta

Fifteen patients ranging in age from 9 to 25 years (median age 10 years), with coarctation of the aorta, were investigated with magnetic resonance (MR) imaging pre- and postoperatively. Three patients were examined because of suggested re-stenosis. Both MR examination and cineangiography were performed in 11 patients. The two techniques were comparable concerning the evaluation of both the site and the severity of coarctation as well as of the occurrence of collateral vessels. MR was considered suitable to replace angiography in the pre- and postoperative assessment of coarctation. The patients were preferably examined with a surface spine coil with ECG-gated sagittal, transverse and parafrontal images. The parafrontal images were necessary in order to minimize mistakes due to partial volume effects at the coarctation site. A surface coil placed over the sternum considerably improved the visualization of the internal mammary arteries.

Cerebrospinal fluid levels of substance P (SP) N-terminal fragment SP1–7 in patients with neuropathic pain

Aims

Neuropathic pain is a complex and painful condition, which is difficult to treat and causes a lot of suffering. The substance P (SP) system is well known to be involved in nociceptive signaling and it has previously been shown that the cerebrospinal fluid (CSF) level of SP is decreased in neuropathic pain. In this study we analyzed CSF from chronic neuropathic pain patients for the levels of SP1–7, an N-terminal fragment of SP with the ability to alleviate thermal as well as mechanical hypersensitivity in different animal models of chronic neuropathic pain, e.g. [1,2].

Methods

CSF was collected from 11 neuropathic pain patients, treated with SCS, who had refrained from using their spinal cord stimulator for 48h. Control CSF was collected from 11 patients without any known neurological disorder, who underwent minor surgery under spinal anesthesia. The CSF samples were analyzed for the levels of SP1–7 using radioimmunoassay.

Results

The results revealed a decrease in the level of SP1–7 compared to controls. We believe that the lower level ofSP1–7 most likely is a consequence of reduced amount of its precursor SP in the neuropathic pain patients.

Conclusions

Our results indicate that the SP system is changed in patients with neuropathic pain and that SP-related peptides, including SP1–7, might serve as biological markers for the patho-physiology of chronic neuropathic pain.

Small constrained SP1-7 analogs bind to a unique site and promote anti-allodynic effects following systemic injection in mice

Previous results have shown that the substance P (SP) N-terminal fragment SP1-7 may attenuate hyperalgesia and produce anti-allodynia in animals using various experimental models for neuropathic pain. The heptapeptide was found to induce its effects through binding to and activating specific sites apart from any known neurokinin or opioid receptor. Furthermore, we have applied a medicinal chemistry program to develop lead compounds mimicking the effect of SP1-7. The present study was designed to evaluate the pharmacological effect of these compounds using the mouse spared nerve injury (SNI) model of chronic neuropathic pain. Also, as no comprehensive screen with the aim to identify the SP1-7 target has yet been performed we screened our lead compound H-Phe-Phe-NH2 toward a panel of drug targets. The extensive target screen, including 111 targets, did not reveal any hit for the binding site among a number of known receptors or enzymes involved in pain modulation. Our animal studies confirmed that SP1-7, but also synthetic analogs thereof, possesses anti-allodynic effects in the mouse SNI model of neuropathic pain. One of the lead compounds, a constrained H-Phe-Phe-NH2 analog, was shown to exhibit a significant anti-allodynic effect.

Treatment of tunnel wash water and implications for its disposal

The use of road tunnels in urban areas creates water pollution problems, since the tunnels must be frequently cleaned for traffic safety reasons. The washing generates extensive volumes of highly polluted water, for example, more than fivefold higher concentrations of suspended solids compared to highway runoff. The pollutants in the wash water have an affinity for particulate material, so sedimentation should be a viable treatment option. In this study, 12 in situ sedimentation trials were carried out on tunnel wash water, with and without addition of chemical flocculent. Initial suspended solids concentration ranged from 804 to 9,690 mg/L. With sedimentation times of less than 24 hours and use of a chemical flocculent, it was possible to reach low concentrations of suspended solids (<15 mg/L), PAH (<0.1 μg/L), As (<1.0 μg/L), Cd (<0.05 μg/L), Hg (<0.02 μg/L), Fe (<200 μg/L), Ni (<8 μg/L), Pb (<0.5 μg/L), Zn (<60 μg/L) and Cr (<8 μg/L). Acute Microtox(®) toxicity, mainly attributed to detergents used for the tunnel wash, decreased significantly at low suspended solids concentrations after sedimentation using a flocculent. The tunnel wash water did not inhibit nitrification. The treated water should be suitable for discharge into recipient waters or a wastewater treatment plant.

Impact of anabolic androgenic steroids on neuropeptide systems

The abuse of anabolic androgenic steroids (AAS) is relatively widely spread and epidemiological studies in the western countries report a prevalence between 1-5 % among males. The impact of these steroids on the strength and muscle mass as well as many of the adverse physical effects that have been observed are well described. Several reports have also revealed severe psychological effects as results of the administration of AAS. Effects such as irritability, aggressiveness, anxiety and depression are reported to be associated with AAS abuse. The mechanistic rationales behind these effects are not well understood. Several systems are likely to be involved, including the monoamine and peptidergic systems. The aim of this review is to highlight the potential role of the neuropeptide systems in the brain with focus on how these systems are affected by repeated administration of AAS.

Nandrolone decanoate administration dose-dependently affects the density of kappa opioid peptide receptors in the rat brain determined by autoradiography

The kappa opioid receptor ligand [(3)H]CI-977 was used to autoradiographically determine the density of kappa opioid receptors in the male rat brain following chronic treatment with the anabolic androgenic steroid nandrolone decanoate at two different doses. As compared to controls, significantly lower densities of the kappa opioid receptor were encountered after two weeks of high dose nandrolone decanoate (15 mg/kg) in the nucleus accumbens shell (16%), lateral hypothalamic area (36%), ventromedial hypothalamic nucleus (37%), dorsomedial hypothalamic nucleus (49%), central amygdaloid nucleus, capsular part (28%), lateral globus pallidus (35%) and in the stria terminalis (24%). Furthermore, an up-regulation of the receptor level was observed in the caudate putamen (18%) and in the dorsal endopiriform nucleus (23%). These alterations in the kappa opioid receptor expression are possibly attributed to a previously observed pronounced impact of nandrolone decanoate on the dynorphinergic system and could also include involvement of the dopaminergic reward system.

Assessing, understanding and modifying nutritional status, eating habits and physical activity in European adolescents: The HELENA (Healthy Lifestyle in Europe by Nutrition in Adolescence) Study

Objectives

To identify the main knowledge gaps and to propose research lines that will be developed within the European Union-funded ‘Healthy Lifestyle in Europe by Nutrition in Adolescence’ (HELENA) project, concerning the nutritional status, physical fitness and physical activity of adolescents in Europe.

Design

Review of the currently existing literature.

Results

The main gaps identified were: lack of harmonised and comparable data on food intake; lack of understanding regarding the role of eating attitudes, food choices and food preferences; lack of harmonised and comparable data on levels and patterns of physical activity and physical fitness; lack of comparable data about obesity prevalence and body composition; lack of comparable data about micronutrient and immunological status; and lack of effective intervention methodologies for healthier lifestyles.

Conclusions

The HELENA Study Group should develop, test and describe harmonised and state-of-the-art methods to assess the nutritional status and lifestyle of adolescents across Europe; develop and evaluate an intervention on eating habits and physical activity; and develop and test new healthy food products attractive for European adolescents.

Peptide conversion--a potential pathway modulating G-protein signaling

Previous and current research has revealed that most neuropeptides induce their actions on cellular systems through specific receptors located on the cell surface. These receptors are known as G-protein coupled receptors, which exert their effects through interaction with ion channels or enzymes located within the cell membrane. Following receptor stimulation and exerting their effects the peptides are inactivated by enzymatic degradation. However, in many cases the active neuropeptides are enzymatically converted to products with retained bioactivity. These bioactive fragments may mimic but also counteract the action of the parent peptide. Thus, the released fragment may serve as a modulator of the response of the original compound. This phenomenon has been found to occur in a number of peptide systems, including the opioid peptides, tachykinins, as well as peptides belonging to the renin-angiotensin system, such as angiotensin II. In some cases the conversion product interacts with the same receptor as the native compound but sometimes it appears that the released fragment interacts with receptors or binding sites distinct from those of the original peptide. This review is focused on peptide fragments released from opioid related peptides, substance P and angiotensin II, that have been shown to modulate the action of their parent compounds.

Assessment of suspended solids concentration in highway runoff and its treatment implication

It is understood that the major pollution from storm water is related to the content of particulate matter. One treatment practice is based on the first flush, i.e. detention of the initial part of the runoff that is considered to contain the highest concentrations of pollutants. This study has evaluated the concentration of total suspended solids in 30 consecutive runoff events during the winter season for an area of 6.7 hectares. A six-lane highway (E4) that has an annual average daily traffic load of 120,000 dominates the area and road de-icing salt (NaCl) and studded tires were in regular use during the studied period. The effluent standard for wastewater of 60 mg TSS per litre applied in EU was used to assess the treatment requirement of storm water. In only two of the events the event mean concentration was below 60 mg 1(-1). In four runoff events a partial event mean concentration below 60 mg 1(-1) was found, in 26 %, 12 %, 11 %, and 2 % respectively of the runoff volume. This would suggest that a capture of the initial part of the runoff for subsequent treatment is less applicable in this type of urban watershed.

Neuropeptide conversion to bioactive fragments--an important pathway in neuromodulation

Biosynthetic pathways for the formation of neuroactive peptides and the processes for their inactivation include several enzymatic steps. In addition to enzymatic processing and degradation, several neuropeptides have been shown to undergo enzymatic conversion to fragments with retained or modified biological activity. This has most clearly been demonstrated for e.g. opioid peptides, tachykinins, calcitonin gene-related peptide (CGRP) as well as for peptides belonging to the renin-angiotensin system. Sometimes the released fragment shares the activity of the parent compound. However, in many cases the conversion reaction is linked to a change in the receptor activation profile, i.e. the generated fragment acts on and stimulates a receptor not recognized by the parent peptide. This review will describe the characteristics of certain neuropeptide fragments having the ability to modify the biological action of the peptide from which they are derived. Focus will be directed to the tachykinins, the opioid peptides, angiotensins as well as to CGRP, bradykinin and nociceptin. The kappa opioid receptor selective opioid peptide, dynorphin, recognized for its ability to produce dysphoria, is converted to the delta opioid receptor agonist Leu-enkephalin, with euphoric properties. The tachykinins, typified by substance P (SP), is converted to the bioactive fragment SP(1-7), a heptapeptide mimicking some but opposing other effects of the parent peptide. The bioactive angiotensin II, known to bind to and stimulate the AT-1 and AT-2 receptors, is converted to angiotensin IV (i.e. angiotensin 3-8) with preference for the AT-4 sites or to angiotensin (1-7), not recognized by any of these receptors. Both angiotensin IV and angiotensin (1-7) are biologically active. For example angiotensin (1-7) retains some of the actions ascribed for angiotensin II but is shown to counteract others. Thus, it is obvious that the activity of many neuroactive peptides is modulated by bioactive fragments, which are formed by the action of a variety of peptidases. This phenomenon appears to represent an important regulatory mechanism that modulates many neuropeptide systems but is generally not acknowledged.

The yeast mediator

The large number of signaling pathways and regulatory proteins that affect transcription highlights a need for funneling of information since transcription of all protein encoding genes is executed by the same set of general transcription factors and RNA polymerase II. This demand is met by large protein complexes such as Mediator that interact with the basic RNA polymerase II machinery and thus adds diversity simply by increasing the surface that is exposed to the incoming signals. The recent description of Mediator-like complexes in metazoans identifies it as a key player in transcriptional regulation.

Reversal of protein-losing enteropathy in a child with Fontan circulation is correlated with central venous pressure after heart transplantation

We report on the reversal of protein-losing enteropathy (PLE) after heart transplantation (HTx) in a 10-yr-old boy with Fontan circulation, previously treated unsuccessfully with heparin for several months. The protein loss continued immediately after the Tx. During the following month, however, a gradual decrease in protein loss was observed, which correlated with a decrease in the inferior vena cava (IVC) pressure. The patient is doing well with a normal serum albumin level and a normal IVC pressure, 2 yr after Tx.

Anabolic-androgenic steroids affect the content of substance P and substance P(1-7) in the rat brain

The effects of intramuscular (i.m.) injections of nandrolone decanoate (15 mg/kg/day), an anabolic-androgenic steroid, on the levels of substance P (SP) and on its N-terminal fragment SP(1-7) were examined in the male rat brain by radioimmunoassay. The results demonstrated that the SP immunoreactivity in amygdala, hypothalamus, striatum, and periaqueductal gray was significantly enhanced, whereas the concentration of the N-terminal fragment SP(1-7) was enhanced in the nucleus accumbens and in periaqueductal gray. In the striatum the steroid induced a decrease in the content of SP(1-7). The relevance of these peptides in connection with anabolic-androgenic steroid-induced aggression is discussed.

The effect on opioid peptides in the rat brain, after chronic treatment with the anabolic androgenic steroid, nandrolone decanoate

In recent years, an increase in abuse of anabolic androgenic steroids (AAS) has been seen among individuals not directly connected to sports. Clinical evidence suggests that abuse of these steroids may result in profound changes in personality, expressed by depressive symptoms, irritability and increased aggression. It is still unknown whether these alterations are related to changes in any particular transmitter system or whether they are persistent or reversible. In this study we focused on AAS effect on the endogenous dynorphin and enkephalin system in the brain. Male rats were given intramuscular injections of the AAS nandrolone decanoate (15 mg/kg), once daily for 2 weeks. The levels of the opioid peptide immunoreactivities (ir) were assessed by radioimmunoassay in two groups immediately after the treatment and in two other groups after additional 3 weeks without any drug treatment (recovery period). The result indicates that chronic AAS treatment increased the activity in the dynorphin B- and Met-enkephalin-Arg(6)Phe(7)-ir in the hypothalamus, striatum and periaqueductal gray (PAG) compared to controls. In addition, the steroid induced an imbalance between the dynorphin and the enkephalin opioid system in the nucleus accumbens, hypothalamus and PAG. This imbalance remained after the recovery period. Since increased peptide activity was found in brain regions regulating emotions, dependence, defensive reactions and aggression, it was suggested that the actual endogenous opioid systems are involved in previously reported AAS-induced changes in these behaviours.

Molecular characterization of the human carbonic anhydrase-related protein (HCA-RP VIII)

The very evolutionarily conserved human carbonic anhydrase-related polypeptide (CA-RP VIII) lacks the carbon-dioxide hydration-activity, characteristic of the enzymatically active carbonic anhydrases. We have expressed HCA-RP VIII as a glutathione-S-transferase fusion protein (GST-HCA-RP VIII). The purified HCA-RP VIII showed a substantially higher apparent molecular weight by gel-filtration compared to the molecular weight calculated from the amino acid sequence, indicating a larger than expected Stoke's radius. Like other studied CA's, the protein unfolds through two transitions at increasing concentrations of guanidine hydrochloride. The far-UV CD spectra of HCA-RP VIII indicates a secondary structure similar to that of the catalytically active HCA II. The very high sequence identity between human and mouse CA-RP VIII (98%), might indicate that the function of the protein involves binding of another protein. However, an attempt to use the GST-HCA-RP VIII fusion protein to affinity purify a ligand was unsuccessful.

Catalytic effects of glutathione peroxidase mimetics on the thiol reduction of cytochrome c

The reduction of ferric cytochrome c by various thiols was studied. It was found that L-cysteine, L-cysteine methyl ester and D-penicillamine were very efficient reductants for cytochrome c, whereas N-acetylated amino acids (N-acetyl-L-cysteine and N-acetyl-D-cysteine) reacted considerably slower. A series of glutathione peroxidase mimetics and related compounds were studied as catalysts for the N-acetyl-L-cysteine reduction of ferric cytochrome c. Diphenyl diselenide, t-butylthio phenyl selenide, S-(phenylseleno)-glutathione, N-(phenylseleno)-phthalimide and alpha-(phenylselenenyl)-acetophenone were all efficient reduction catalysts. Diphenyl disulfide, Ebselen and several derivatives thereof were less potent catalysts whereas diaryl selenides and diphenyltelluride did not affect the rate of reduction when present in catalytic amounts. The catalysis of diphenyl diselenide, selenosulfides, alpha-(phenylselenenyl)acetophenone, N-(phenylseleno)-phthalimide and Ebselen and derived compounds was suggested to involve the formation of areneselenolate ions as redox-active species capable of transferring one electron to the ferric cytochrome c. The resulting selenium centered arylseleno radicals would then dimerize to regenerate the catalyst in the diselenide form. In the presence of diaryl ditellurides and N-acetyl-L-cysteine, ferric cytochrome c was also rapidly reduced. This reaction was stoichiometric with respect to the ditelluride reagent.

Estimation of Doppler gradients at rest and during exercise in patients with recoarctation of the aorta

In patients with suspected recoarctation of the aorta the estimation of the pressure difference between the arms and legs is an important part of the examination. Because this difference is often augmented when the circulation is stressed by exercise, exercise tests are a useful part of the evaluation. Doppler echocardiography was used to estimate this pressure difference in 16 adult patients in whom simultaneous pressure and Doppler recordings were made both at rest and during exercise. There was a close correlation between the invasive peak instantaneous gradient and the Doppler gradient both at rest and during exercise. There was only a moderate correlation between the invasive peak to peak gradient and the Doppler gradient at rest and during exercise. Doppler echocardiography is recommended as an easy and accurate method of estimating the peak instantaneous gradient both at rest and during exercise in patients with suspected recoarctation.

Magnetic resonance imaging and angiography for the assessment of coarctation of the aorta

Fifteen patients ranging in age from 9 to 25 years (median age 10 years), with coarctation of the aorta, were investigated with magnetic resonance (MR) imaging pre- and postoperatively. Three patients were examined because of suggested re-stenosis. Both MR examination and cineangiography were performed in 11 patients. The two techniques were comparable concerning the evaluation of both the site and the severity of coarctation as well as of the occurrence of collateral vessels. MR was considered suitable to replace angiography in the pre- and postoperative assessment of coarctation. The patients were preferably examined with a surface spine coil with ECG-gated sagittal, transverse and parafrontal images. The parafrontal images were necessary in order to minimize mistakes due to partial volume effects at the coarctation site. A surface coil placed over the sternum considerably improved the visualization of the internal mammary arteries.

The internal mammary artery origin flap aortoplasty in coarctation of the aorta

The left internal mammary artery (IMA) was divided proximally to form an integral part of the repair in coarctation. After resection of the internal coarctation ridge, the origin of the IMA was obliquely divided, opened to required length and thus fashioned as a widening flap for aortoplasty. This procedure preserves distal continuity of the IMA with direct blood supply to the breast. The 'origin flap' aortoplasty gave promising early results in six patients and 10-17 years with aortic coarctation and IMA of suitable calibre and good quality.

The internal mammary artery free and flap aortoplasty in coarctation of the aorta

A technique for correction of aortic coarctation is described in which the left internal mammary artery (IMA) is distally divided for integration in the repair. After resection of the internal coarctation ridge, the distal end of the freed IMA is obliquely severed, opened to required length and thus fashioned as a widening flap suitable fro aortoplasty. IMA free end flap aortoplasty gave promising early results in seven patients aged 10-15 years with aortic coarctation and IMA of good quality and calibre.

Neonatal endocarditis requiring surgery

A case of infective endocarditis in a neonate is reported. Echocardiography demonstrated a large (1 X 1.5 cm) vegetation on the anterior mitral leaflet protruding into the ventricle during diastole. The left atrium was enlarged and Doppler showed mitral regurgitation. Excision of the vegetation during effective antibiotic treatment involved no complications. Although histologically the endocarditis was in the early stage of healing, surgical removal of large, floppy vegetations is advocated because of the unpredictable risk of catastrophic embolization.

The internal mammary artery as subclavian artery substitute in repair of coarctation of the aorta with subclavian flap technique

In three children, aged 11, 11 and 13 years, long isthmic tubular hypoplasia of the aorta technically precluded resection and end-to-end anastomosis. The coarctation was instead corrected by means of a subclavian flap. Anastomosis between the distal end of the left internal mammary artery and the descending aorta permitted perfusion of the remaining portion of the subclavian artery. At invasive reexamination 6 months after surgery, there was adequate functional and anatomic relief of coarctation in all three children. The three mammary artery-aorta anastomoses were patent, which probably prevented the potential ischemia of the left arm after ligation of the subclavian artery.

Cuff pressures and Doppler gradients after coarctectomy. A long-term follow-up

Fourty-six adult patients operated on as children with resection and end to end anastomosis because of coarctation of the aorta were studied. The age at operation was 7 to 13 years (mean age 10 years) and at follow-up 18 to 28 years (mean age 21 years). Arm and thigh cuff pressure was measured at rest, during and immediately after submaximal exercise. The systolic gradients were also estimated using continuous wave Doppler. Systolic blood pressure at rest was 150 mmHg or more in 12 patients (26%). The cuff pressure at rest correlated well with arm-leg gradients at rest and at work, and also with the Doppler gradients at rest. Doppler gradients slightly underestimated invasively measured gradients. The results imply that postoperative hypertension was explained by residual mechanical obstruction.