Transfluthrin Spatial Repellent on US Military Materials Reduces Culex tarsalis Incursion in a Desert Environment

Standard residual pesticides applied to US military materials such as camouflage netting can reduce mosquito biting pressure in the field but may contribute to the evolution of resistance. However, residual applications of a spatial repellent such as transfluthrin could allow mosquitoes the opportunity to escape, only inducing mortality if insects linger, for example after becoming trapped in a treated tent. In this study we investigated the capability of transfluthrin on 2 types of US military material to reduce natural populations of disease vector mosquitoes in a cool-arid desert field environment in southern California. We found that transfluthrin could reduce Culex tarsalis incursion into protected areas by up to 100% upon initial treatment and up to 45% for at least 16 days posttreatment, showing that this compound could be an effective element in the US Department of Defense integrated vector management system appropriate for further study.

Regeneration von Knochendefekten mit computergesteuerter Herstellung von Gerüstträgern

Die Behandlung ausgedehnter Knochen-defekte nach Traumata oder durch Tumoren stellt nach wie vor eine signifikante Heraus-forderung im klinischen Alltag dar. Aufgrund der bestehenden Limitationen aktueller Therapiestandards haben Knochen-Tissue-Engineering (TE)-Verfahren zunehmend an Bedeutung gewonnen. Die Entwicklung von Additive-Manufacturing (AM)-Verfahren hat dabei eine grundlegende Innovation ausgelöst: Durch AM lassen sich dreidimensionale Gerüstträger in einem computergestützten Schichtfür-Schicht-Verfahren aus digitalen 3D-Vorlagen erstellen. Wurden mittels AM zunächst nur Modelle zur haptischen Darstellung knöcherner Pathologika und zur Planung von Operationen hergestellt, so ist es mit der Entwicklung nun möglich, detaillierte Scaffoldstrukturen zur Tissue-Engineering-Anwendung im Knochen zu fabrizieren. Die umfassende Kontrolle der internen Scaffoldstruktur und der äußeren Scaffoldmaße erlaubt eine Custom-made-Anwendung mit auf den individuellen Knochendefekt und die entsprechenden (mechanischen etc.) Anforderungen abgestimmten Konstrukten. Ein zukünftiges Feld ist das automatisierte ultrastrukturelle Design von TE-Konstrukten aus Scaffold-Biomaterialien in Kombination mit lebenden Zellen und biologisch aktiven Wachstumsfaktoren zur Nachbildung natürlicher (knöcherner) Organstrukturen.

Schmerztherapie mit Metamizol

Gegenstand und Ziel: Die vorliegende Arbeit soll den derzeitigen Wissensstand über die pharmakologische und klinische Wirkung von Metamizol bei Hund, Katze Maus und Ratte vorstellen. Metamizol erlebt in den letzten Jahren eine Renaissance, vor allem in der Humanmedizin. Lange Zeit wurde Metamizol als schwaches Analgetikum mit vorwiegend antipyretischer Wirkung eingestuft und die pharmakologische Wirkung war lange Zeit unbekannt. Heute ist wissenschaftlich nachgewiesen, dass zentrale und periphere Wirkmechanismen für die potente analgetische Wirkung von Metamizol verantwortlich sind. Opioiderge Mechanismen und Hemmung der Zyklooxygenasen gelten heute als gesicherte Wirkmechanismen von Metamizol. Metamizol wirkt aber auch antipyretisch, gering antiphlogistisch, spasmolytisch und antikonvulsiv. Die analgetische Wirkung ist mit der von Opioiden vergleichbar. Die hypotensive Nebenwirkung bei intravenöser Injektion lässt sich durch langsame Applikation weitestgehend vermeiden. Eine Agranulozytose wurde bisher in der Veterinärmedizin nicht beobachtet und auch in der Humanmedizin liegt die Inzidenz unter 0,008%. Die Magen-Darm-Trakt-Verträglichkeit von Metamizol ist als gut einzustufen. Schlussfolgerung und klinische Relevanz: Der vorliegende Artikel zeigt, dass Metamizol auch in der Veterinärmedizin potent analgetisch wirkt und die Verträglichkeit als sehr gut zu bewerten ist.

Macroscopic phase separation of superconductivity and ferromagnetism in Sr0.5Ce0.5FBiS2-x Se x revealed by μSR

The compound Sr_0.5Ce_0.5FBiS₂ belongs to the intensively studied family of layered BiS₂ superconductors. It attracts special attention because superconductivity at T_sc = 2.8 K was found to coexist with local-moment ferromagnetic order with a Curie temperature T_C = 7.5 K. Recently it was reported that upon replacing S by Se T_C drops and ferromagnetism becomes of an itinerant nature. At the same time T_sc increases and it was argued superconductivity coexists with itinerant ferromagnetism. Here we report a muon spin rotation and relaxation study (μSR) conducted to investigate the coexistence of superconductivity and ferromagnetic order in Sr_0.5Ce_0.5FBiS_2−xSe_x with x = 0.5 and 1.0. By inspecting the muon asymmetry function we find that both phases do not coexist on the microscopic scale, but occupy different sample volumes. For x = 0.5 and x = 1.0 we find a ferromagnetic volume fraction of ~8 % and ~30 % at T = 0.25 K, well below T_C = 3.4 K and T_C = 3.3 K, respectively. For x = 1.0 (T_sc = 2.9 K) the superconducting phase occupies most (~64 %) of the remaining sample volume, as shown by transverse field experiments that probe the Gaussian damping due to the vortex lattice. We conclude ferromagnetism and superconductivity are macroscopically phase separated.

Comparison of dipyrone/propofol versus fentanyl/propofol anaesthesia during surgery in rabbits

In this study, the investigation of the intraoperative effects of dipyrone (metamizol) on heart rate (HR), mean arterial pressure (MAP) and analgesic efficacy in rabbits is described for the first time. This was carried out to evaluate the cardiovascular stability achieved using dipyrone compared with fentanyl. In this prospective study, 17 female New Zealand White rabbits were randomly allocated to either one of two groups: dipyrone/propofol (DP) or fentanyl/propofol (FP). Anaesthesia was induced in both groups using propofol to effect (4.0–8.0 mg/kg intravenously) until the swallowing reflex was lost for intubation. After induction, anaesthesia was maintained with continuous infusion of propofol 1.5–1.7 mg/kg/min intravenously. Analgesics were then injected in defined boluses of either dipyrone 65 mg/kg or fentanyl 0.0053 mg/kg. After surgical tolerance, defined as loss of the ear pinch reflex and loss of the anterior and posterior pedal withdrawal reflex, was achieved, two surgical procedures were performed. The surgical procedures (implantation of either a pacemaker or an electrocardiogram transmitter), both require a comparable level of analgesic depth. During and after surgery, clinical variables, such as MAP, HR, peripheral arterial oxygen saturation (SpO2) and end-tidal CO2 (Pe′CO2) were recorded simultaneously every 2 min. Eight time points were chosen for comparison: baseline, surgical tolerance (ST), values at 10, 20 and 30 min after reaching ST, values at the end of propofol infusion (EI) and data at 10 and 20 min after EI. Both FP and DP combinations provided effective anaesthesia and analgesia in rabbits. In both groups a significant decrease of HR and MAP was measured. The results of this study indicate that the non-opioid drug dipyrone produces similar analgesic and even better cardiovascular effects by trend in rabbits. Therefore we conclude that dipyrone in combination with propofol can be used as an alternative to FP for intraoperative analgesia.

Analysis of cerebrospinal fluid in healthy rabbits and rabbits with clinically suspected encephalitozoonosis

Samples of uncontaminated cerebrospinal fluid (csf) were collected from the cisterna magna of 20 healthy laboratory rabbits and 21 pet rabbits with vestibular disease and/or paresis due to clinically suspected encephalitozoonosis. In the healthy rabbits' csf the leucocyte count was <or=4 leucocytes/microl (median 1.5 microl) and the concentration of protein ranged from 0.13 to 0.31 g/l (median 0.24 g/l). In the diseased rabbits, the number of leucocytes ranged from 1 to 87/microl (median 15/microl; P<0.001), and the concentration of protein ranged from 0.31 to 1.54 g/l (median 0.79 g/l; P<0.001); a cytological evaluation showed that they had greater numbers of lymphocytes and monocytes. It was concluded that encephalitozoonosis in rabbits is characterised by lymphomonocytic pleocytosis in CSF.

Lipoprotein(a) in patients initiating antiretroviral therapy

OBJECTIVES

The interaction between lipoprotein(a), an emerging cardiovascular risk factor, and antiretrovirals (ARVs) has been less well studied than the interaction between either cholesterol or triglycerides and these drugs. In this study we assessed the effect of initiating antiretroviral therapy (ART) on lipoprotein(a) levels.

METHODS

Fasting samples from 95 patients initiating ART with nucleoside/nucleotide reverse transcriptase inhibitors plus nonnucleoside reverse transcriptase inhibitors or protease inhibitors were obtained. Lipids and lipoproteins were determined until week 48.

RESULTS

As in the general population, the study population showed a highly skewed lipoprotein(a) distribution (median 9.9 mg/dL, range 0.1-110 mg/dL). The study population was divided into individuals with lipoprotein(a) >or=30 mg/dL at baseline (n=28) and those with <30 mg/dL (n=67). Almost exclusively, patients with high lipoprotein(a) at baseline (median 51.6 mg/dL) showed a profound increase of median 26.7 mg/dL (week 24). This effect was not associated with specific ARVs and was independent of changes in other lipids. The low-lipoprotein(a) group (baseline median 7 mg/dL) showed a small increase of median 2.6 mg/dL (week 24).

CONCLUSIONS

Marked increases in lipoprotein(a) after initiation of ART were mainly restricted to patients with high baseline levels. This may have clinical implications as patients with high lipoprotein(a) are at higher risk for myocardial infarction and stroke.

Fetal spina bifida repair--current trends and prospects of intrauterine neurosurgery

Myelomeningocele is a common dysraphic defect leading to severe impairment throughout the patient's lifetime. Although surgical closure of this anomaly is usually performed in the early postnatal period, an estimated 330 cases of intrauterine repair have been performed in a few specialized centers worldwide. It was hoped prenatal intervention would improve the prognosis of affected patients, and preliminary findings suggest a reduced incidence of shunt-dependent hydrocephalus, as well as an improvement in hindbrain herniation. However, the expectations for improved neurological outcome have not been fulfilled and not all patients benefit from fetal surgery in the same way. Therefore, a multicenter randomized controlled trial was initiated in the USA to compare intrauterine with conventional postnatal care, in order to establish the procedure-related benefits and risks. The primary study endpoints include the need for shunt at 1 year of age, and fetal and infant mortality. No data from the trial will be published before the final analysis has been completed in 2008, and until then, the number of centers offering intrauterine MMC repair in the USA is limited to 3 in order to prevent the uncontrolled proliferation of new centers offering this procedure. In future, refined, risk-reduced surgical techniques and new treatment options for preterm labor and preterm rupture of the membranes are likely to reduce associated maternal and fetal risks and improve outcome, but further research will be needed.

Changes in intra-abdominal pressure, hemodynamics, and peak inspiratory pressure during gastroscopy in a porcine model

BACKGROUND AND STUDY AIMS

The aim of this experimental study was to assess the effect of gastric insufflation on intra-abdominal pressure (IAP) and associated hemodynamic and respiratory changes during upper gastrointestinal endoscopy.

METHODS

Measurements were taken from pigs under general anesthesia with controlled ventilation. Gastroscopy was carried out with continuous insufflation of air by a standard endoscopic light source/insufflator. The cardiac index and global end-diastolic volume index (GEDVI; reflecting preload) were measured by transpulmonary thermodilution. IAP, heart rate, mean arterial pressure (MAP), central venous pressure, systemic vascular resistance index (SVRI; reflecting afterload), peak inspiratory pressure (PIP), and oxygenation (SaO (2)) were also recorded.

RESULTS

A total of 266 paired measurements (at the time of transpulmonary thermodilution) were taken from 14 animals. During air insufflation, we observed a significant rise in IAP in all animals up to intermittent values of 22 mm Hg. IAP and PIP correlated well (r = 0.666, P < 0.001), with the latter reaching values as high as 45 mbar in one pig, leading to respiratory compromise. Only marginal changes in heart rate, and a continuous, almost significant rise in MAP (due to a significant increase in SVRI) were recorded. We observed a slight increase in GEDVI, predominantly during the initial phase of air insufflation. The cardiac index showed no substantial changes. There were no episodes of hemodynamic instability, nor a decline in SaO (2).

CONCLUSIONS

Air insufflation during gastroscopy resulted in a significant increase in IAP. The main clinically relevant finding was a steady increase in SVRI. Major increments in PIP suggest a role of intra-abdominal hypertension in otherwise unexplained respiratory compromise during upper gastrointestinal endoscopy.

A Comparative Clinical Study of Three Different Dosages of Intramuscular Midazolam?Medetomidine?Ketamine Immobilization in Cats

A low dose of midazolam-medetomidine-ketamine (MMK) combination was evaluated in three increasing dosages. Each of the 18 cats was randomly allocated for several times to one of four groups. Five minutes after premedication with intramuscular (IM) 0.04 mg/kg atropine, group A (n = 43), B (n = 40) and C (n = 28) all were anaesthetized with 0.5 mg/kg midazolam, combined with 10, 20 or 30 microg/kg medetomidine, and 1.0, 2.0 or 3.0 mg/kg ketamine, respectively, IM in one syringe. Group D (n = 11) received the established combination of 50 microg/kg medetomidine and 10.0 mg/kg ketamine for comparison. Because this study was in cooperation with a project on dental prophylaxis, cats had to be immobilized for approximately 1 h. Therefore, anaesthesia was prolonged with propofol to effect, if necessary. Duration of MMK anaesthesia was between 30 +/- 15, 45 +/- 19 and 68 +/- 28 min in groups A, B and C respectively. A significant decrease of respiratory rate was observed with increasing dosage, but venous carbon dioxide (pCO(2)) and pH values in combination with arterial oxygen saturation (SpO(2)) values were not alarming. The diastolic blood pressure particularly showed an increase. MMK combination A showed the best cardiovascular results, but it cannot be recommended due to disadvantages like a long induction time sometimes accompanied by excitations and the short duration of surgical immobilization. Dosage C in contrast had fewer side effects but less favourable cardiovascular results and a longer recovery period. However, either dosage B or C was suitable as a repeatable IM immobilization method for non-invasive procedures in healthy cats.

Effect of pneumoperitoneum on hemodynamics and inspiratory pressures during natural orifice transluminal endoscopic surgery (NOTES): an experimental, controlled study in an acute porcine model

BACKGROUND AND STUDY AIM

Physiologic reactions during natural orifice transluminal endoscopic surgery (NOTES) may differ from those at laparoscopy. This experimental study assessed the effect of pneumoperitoneum induced by endoscope air pump on hemodynamics and inspiratory pressures during transgastric peritoneoscopy.

METHODS

Transgastric peritoneoscopy was performed in 11 female pigs (35 - 50 kg) under general anesthesia. Five pigs with controlled insufflation and no endoscopic intervention served as controls. Cardiac index and global end-diastolic volume index (GEDVI; reflecting preload) were measured every 3 minutes by transpulmonary thermodilution. We also recorded: intra-abdominal pressure (IAP), heart rate, mean arterial pressure (MAP), systemic vascular resistance index (SVRI; reflecting afterload), peak inspiratory pressure (PIP), and oxygenation.

RESULTS

One study group pig was excluded from analysis because of a major complication related to the gastric incision. In the remaining 15 animals we performed 264 paired measurements. On-demand insufflation in the study group produced wide variation in intra-abdominal pressures; the control group demonstrated minimal fluctuation around a predetermined value. In the study group, IAP and PIP correlated well ( R = 0.667, P = 0.000), with maximum PIP values of 40 mbar contrasting with the control group maximum of 26.5 mbar. Hemodynamically, there was a minor decrease of cardiac index in the study group (in contrast to the control group). Relative changes in cardiac index and IAP during transgastric peritoneoscopy correlated highly significantly ( R = - 0.416, P = 0.000). Neither group showed hemodynamic instability or decline in oxygen saturation.

CONCLUSIONS

On-demand insufflation with a standard endoscopic light source/insufflator resulted in a marked median increase and wide variation in IAP throughout transgastric peritoneoscopy. Hemodynamic changes were moderate. However, major increases in PIP suggest a need for stricter control of intra-abdominal hypertension during NOTES.

Surgical Therapy of Peripheral Nerve Lesions: Current Status and New Perspectives

The severe functional deficits in patients suffering from traumatic peripheral nerve damage underline the necessity of an optimal therapy. The development of microsurgical techniques in the sixties contributed significantly to the progress in nerve repair. Since then, no major clinical innovation has become established. However, with an increased understanding of cellular and molecular mechanisms underlying nerve regeneration, various tubulization concepts have been developed which yield possible alternatives to direct suturing and to autologous nerve grafting in cases of short nerve defects. The vast knowledge gathered in the field of nerve regeneration needs to be further exploited in order to develop alternative therapeutic strategies to nerve autografting, which can result in donor-site defects and often lead to inappropriate results. Considering the encouraging results from preclinical studies, innovative nerve repair strategies are likely to improve the outcome of reconstructive surgical interventions. This paper outlines, in addition to the fundamentals of nerve regeneration, the current treatment options for defects of peripheral nerves. This article also reviews the developments in the use of alternative nerve guides and demonstrates new perspectives in the field of peripheral nerve reconstruction.

Distribution of two Asian-related coding SNPs in the MC1R and OCA2 genes

Very little is known about the genes and mechanisms affecting skin lightening in Asian populations. In this study, two coding SNPs, c.G1129A (R163Q) at the MC1R (melanocortin 1 receptor) gene and c.A1962G (H615R) at the OCA2 (oculocutaneous albinism type II) gene, were investigated in a total of 1,809 individuals in 16 populations from various areas. The Q163 and R615 alleles prevailed almost exclusively in East and Southeast Asian populations. Wright's F (ST) was 0.445 for R163Q and 0.385 for H615R among the 16 populations. The frequency of the Q163 allele was higher in Northeast Asians than in Southeast Asians. The frequency of the R615 allele was highest in South China and unlikely to be associated with levels of ultraviolet radiation. This allele may be a good marker to study the genetic affinity among East Asians because of its restricted distribution and marked difference in allele frequency.

Transgastric in vivo histology in the peritoneal cavity using miniprobe-based confocal fluorescence microscopy in an acute porcine model

BACKGROUND AND STUDY AIMS

Natural orifice transluminal endoscopic surgery (NOTES) is an emerging technology. Apart from its therapeutic implications, this type of access to the peritoneal cavity might also be useful for targeted in vivo histological investigation by means of confocal fluorescence microscopy. In this study we therefore aimed to assess the feasibility of miniprobe-based confocal fluorescence microscopy during transgastric endoscopy in an acute porcine model.

MATERIALS AND METHODS

Transgastric in vivo histology was performed in five pigs, under general anesthesia. After incision of the anterior gastric wall, a double-channel video gastroscope was advanced into the peritoneal cavity. A flexible confocal miniprobe was introduced through the instrument channel of the endoscope after intravenous injection of 10 mL of fluorescein 1% in four of the pigs and of 50 mL of fluorescein isothiocyanate-dextran 150 000 4% in the fifth pig. The tip of the miniprobe was then placed on the peritoneal layer, the liver, and the spleen for confocal laser microscopy.

RESULTS

Probes were easily attached to the peritoneal layer, the liver, and the spleen under direct visualization with the endoscope. Dynamic microscopic images of these organs were obtained with a frame rate of 12 frames per second. The flow of erythrocytes through blood vessels could be seen. The microstructural components of organs, such as lobules of the liver, were also easily identified.

CONCLUSIONS

In vivo histology in the peritoneal cavity is feasible during NOTES and this technique combines the minimally invasive approach to the intraperitoneal organs afforded by NOTES and real-time, in vivo acquisition of dynamic histological images.

Distribution of the F374 Allele of the SLC45A2 (MATP) Gene and Founder-Haplotype Analysis

The membrane-associated transporter protein (MATP) plays an important role in melanin synthesis. The L374F mutation in the SLC45A2 gene encoding MATP has been suggested to be associated with skin colour in major human populations. In this study more detailed distribution of the F374 allele was investigated in 1649 unrelated subjects from 13 Eurasian populations and one African population. The highest allele frequency was observed in Germans (0.965); French and Italians showed somewhat lower frequencies; and Turks had an intermediate value (0.615). Indians and Bangladeshis from South Asia were characterized by low frequencies (0.147 and 0.059, respectively). We also found the F374 allele in some East and Southeast Asian populations, and explained this by admixture. Haplotype analysis revealed that the haplotype diversity was much lower in Germans than in Japanese, and suggest that the L374F mutation occurred only once in the ancestry of Caucasians. The large differences in distribution of the F374 allele and its haplotypes suggest that this allele may be an important factor in hypopigmentation in Caucasian populations.

Evaluation der Perfusion von Lappenplastiken mittels Laserfluoreszenz von Indocyaningrün

Prediction of necrosis in critically perfused skin flaps is difficult and rarely precise. An early detection of insufficiently perfused skin is highly desirable since it may lead to surgical decisions such as operative flap revision or early resection. The application of laser-induced indocyanine green (ICG) fluoroscopy allows an objective quantification of skin perfusion and a high topographical resolution. Aim of the present study is to determine a threshold value for flap perfusion under well-defined experimental conditions and test the validity of the results in the clinical application. Twenty overdimensioned random pattern flaps with a length to width ratio of 4 : 1 (8 x 2 cm) were dissected at the anterior abdominal wall of 20 male Sprague-Dawley rats weighing 365 g on average. ICG fluorescence was performed at the end of the operation by intravenous injection of 1 g ICG/kg bodyweight into a tail vein and digital recording. On the seventh postoperative day, both the necrotic and surviving areas of the flaps were measured and the ICG-fluorescence was analysed in the areas that had undergone necrosis. 41 flaps with areas of critical perfusion (18 skin flaps, 13 muscle flaps, 8 replantations) were analysed in 39 patients. The surviving part of the flap had a mean perfusion index of 62 % compared to reference skin. The distal parts of the flap that necrotized during the experiment showed an average perfusion index of 19 % postoperatively. Differences were statistically significant (p < 0.001). In clinical application, a number of 13 flaps were found to have a perfusion index less than 25 % in a region of critical perfusion. Eleven of these developed a partial necrosis in that region, one flap underwent total necrosis. Indocyanine green fluoroscopy allows a detailed topographical analysis of flap perfusion and the prediction of necrosis. Experimental findings presented a threshold value for the perfusion index of 25 % which could be confirmed in clinical application.

Foetal surgery and cleft lip and palate: current status and new perspectives

Now-a-days, high-resolution ultrasound allows an accurate and relatively early diagnosis of congenital malformations. In a limited number of such conditions foetal surgery may be lifesaving. However, premature labour has been the major drawback for open foetal surgery. Recently, improvement of video-endoscopic technology has boosted the development of operative techniques for feto-endoscopic surgery, which has been demonstrated to be less invasive than the open approach. Main clinical application of fetoscopic procedures today is the treatment of feto-foetal transfusion syndrome. Although still in development, feto-endoscopic surgery seems to offer new hope for surgical foetal therapy not only in cases of life threatening conditions. Experimental intrauterine correction of cleft lip and palate (CLP) has been lately performed using the feto-endoscopic approach. This procedure offers two major advantages: first, scarless foetal wound healing and bone healing without callus formation, which would also allow a better/normal maxillary growth, and second, significant decrease of foetal and maternal morbidity. Herein, we report the current status of experimental and clinical foetal surgery and propose possible directions for continuing research to make intrauterine procedures safer. Furthermore, we discuss current knowledge and new perspectives of experimental foetal cleft lip and palate repair, which in the future may lead to such excellent results in the operative treatment of clefts, that less or no secondary corrections and therapies, such as orthodontic, dental, logopedic, etc. would be needed. Only if these conditions can be fulfilled, will we be able to improve substantially our therapy for the human foetus with a cleft lip and palate. In spite of all efforts, however, it must be considered that it may not ever be possible to find the optimal treatment method for this or other craniofacial malformations.

Nerve Replacement Strategies for Cavernous Nerves

OBJECTIVE

This article reviews novel restorative therapies for cavernous nerves that may be used to replace resected cavernous nerves at the time of pelvic surgery.

METHODS

A literature-based presentation (Medline search) on current nerve replacement strategies was conducted with emphasis on neurobiological factors contributing to the restoration of erectile function after cavernous nerve injuries.

RESULTS

A promising alternative to autologous nerve grafts for extending the length of successful nerve regeneration are artificial nerve guides. The addition of neurotrophic factors, extracellular matrix components and Schwann cells has been shown to promote cavernous nerve regeneration. Neurotrophic factors can be incorporated in the scaffold or can be supplied by cells seeded into the stroma. The regenerative capacity of these cells can be further enhanced by genetic modification with neurotrophic factor encoding genes.

CONCLUSIONS

Artificial nerve guides, especially biodegradable ones containing growth-promoting factors or cells, are a promising option for the repair of cavernous nerve lesions.

Tissue Engineering erektiler Nerven

Dissection of the cavernous nerves eliminates spontaneous erections and may lead to irreversible erectile dysfunction due to degeneration of cavernous tissue. Novel procedures to reconstruct penile innervation include cavernous nerve interposition grafting and neurotrophic treatments to revitalize penile neural input, evaluated thus far in various preclinical models of cavernous nerve injury. Schwann cells crucially contribute to successful axonal regeneration by mechanical and paracrine mechanisms in the injured nerve, and Schwann cells seeded into guidance channels have been successfully employed to support regeneration in animal models of cavernous nerve injury. Gene therapy, tissue engineering, and reconstructive techniques have been combined to deliver neurotrophic factors and recover erectile function.

Schwann cell seeded guidance tubes restore erectile function after ablation of cavernous nerves in rats

PURPOSE

Dissection of the cavernous nerves eliminates spontaneous erections. We evaluated the ability of Schwann cell seeded nerve guidance tubes to restore erections after bilateral cavernous nerve resection in rats.

MATERIALS AND METHODS

Sections (5 mm) of the cavernous nerve were excised bilaterally, followed by immediate bilateral microsurgical reconstruction. In 10 animals per group (20 study nerves) reconstruction was performed by genitofemoral nerve interposition, interposition of silicone tubes or interposition of silicone tubes seeded with homologous Schwann cells. As the control 10 animals (20 study nerves) underwent sham operation (positive control) and bilateral nerve ablation (without reconstruction) was performed in a further 10 (negative control). Erectile function was evaluated 3 months postoperatively by relaparotomy, electrical nerve stimulation and intracavernous pressure recording.

RESULTS

After 3 months neurostimulation resulted in an intact erectile response in 90% (18 of 20) of Schwann cell grafts, while treatment with autologous nerves (30% or 6 of 20) or tubes only (50% or 10 of 20) was less successful (p <0.01). Whereas untreated ablated rats showed no inducible erections (0% or 0 of 20), all sham operated animals had an intact erectile response (100% or 20 of 20). Maximum intracavernous pressure upon electrostimulation was significantly elevated using Schwann cell grafts compared to results in the other treatment groups (p <0.001). Morphological evaluation revealed advanced regeneration within Schwann cell grafts.

CONCLUSIONS

Schwann cell seeded guidance tubes restore erectile function after the ablation of cavernous nerves in rats and they are superior to autologous nerve grafts.

Anaesthesia with Midazolam/Medetomidine/Fentanyl in Chinchillas (Chinchilla lanigera) Compared to Anaesthesia with Xylazine/Ketamine and Medetomidine/Ketamine

We studied four different drug regimes for anaesthetic management in chinchillas and evaluated and compared their cardiovascular and respiratory effects. In this randomized, cross-over experimental study, seven adult chinchillas, five females, two males [515 +/- 70 (SD) g] were randomly assigned to one of the following groups: group 1 [midazolam, medetomidine and fentanyl (MMF), flumazenil, atipamezole and naloxone (FAN); MMF-FAN] received 1.0 mg/kg midazolam, 0.05 mg/kg medetomidine and 0.02 mg/kg fentanyl i.m., and for reversal 0.1 mg/kg flumazenil, 0.5 mg/kg atipamezole and 0.05 mg/kg naloxone s.c. after 45 min; group 2 (MMF) 1.0 mg/kg midazolam, 0.05 mg/kg medetomidine and 0.02 mg/kg fentanyl i.m.; group 3 [xylazine/ketamine (X/K)] 2.0 mg/kg xylazine and 40.0 mg/kg ketamine i.m.; and group 4 [medetomidine/ketamine (M/K)] 0.06 mg/kg medetomidine and 5.0 mg/kg ketamine i.m. Reflexes were judged to determine anaesthetic stages and planes. Anaesthesia with X/K and M/K was associated with a prolonged surgical tolerance and recovery period. By reversing MMF, recovery period was significantly shortened (5 +/- 1.3 min versus 40 +/- 10.3 min in MMF without FAN, 73 +/- 15.0 min in X/K, and 31 +/- 8.5 min in M/K). Without reversal, MMF produced anaesthesia lasting 109 +/- 16.3 min. All combinations decreased respiratory and heart rate but compared with X/K and M/K, respiratory and cardiovascular complications were less in the MMF groups. Focussing on the clinical relevance of the tested combinations, completely reversible anaesthesia showed two major advantages: anaesthesia can be antagonized in case of emergency and routinely shortens recovery. In small animals particularly these advantages lead to less complications and discomfort and thus often can be lifesaving. As all analgesic components (medetomidine and fentanyl) are reversed, postoperative analgesia should be provided before reversal of anaesthesia.

Fetale Wundheilung

The characteristic of fetal wound healing is scarless wound repair in early gestation. During the last two decades, intensive research efforts have focused on unraveling the molecular regulations underlying the phenomenon of scarless wound healing. Better understanding of synthesis and degradation will enable us to develop important therapeutic options for the prevention and reduction of scarring. The aim of this article is to present an overview, discuss the most important research works of the last two decades on the field of fetal wound healing, and report current therapeutic developments for the modulation of adult wound repair. Recent experimental results using these new therapeutic approaches are very promising and present great possibilities and chances for future surgery.

[Experimental endoscopic intrauterine surgery for craniofacial malformations such as the cleft lip and palate]

INDICATION FOR FETAL SURGERY: The widespread use of high-resolution ultrasound in prenatal diagnosis allows nowadays an accurate and early diagnosis of congenital malformations. Some of these can be corrected surgically. In certain cases intrauterine surgery could present functional and aesthetic advantages or be even lifesaving. Due to the extreme sensitiveness of the fetal patient and the fetal membranes, only some defined anomalies currently meet the criteria for intrauterine surgery. However, the list can change in the future since prenatal diagnosis, technical advances, and knowledge of pathophysiology improve constantly.

ENDOSCOPIC INTRAUTERINE SURGERY

Additionally, the recent development of endoscopic intrauterine surgery represents a new and more careful possibility for intrauterine surgery. Endoscopic procedures could avoid the disadvantages of open intrauterine surgery and thus make fetal operations safer, in life-threatening as well as in non-life-threatening malformations such as cleft lip and palate (CLP). The main advantages of these procedures are (1) scarless wound healing and bone healing without callus formation that leave to expect normal growth of the midface and (2) lower fetal and maternal morbidity.

DISCUSSION

Based on the results achieved until now, it can be stated that at present the intrauterine operation of CLP on humans cannot be recommended. The high morbidity and mortality risk for mother and fetus cannot be counterbalanced by the unsatisfactory results of a prenatal operation.

CONCLUSION

In this study first results of an experimental investigation with the new endoscopic techniques are presented, whereby the possibilities for optimization and quality improvement of the intrauterine surgical procedures are analyzed in detail.

Characterization of genomic rearrangements of the alpha1-acid glycoprotein/orosomucoid gene in Ghanaians

In this study, the structure of the alpha1-acid glycoprotein (AGP), or orosomucoid (ORM), gene was investigated in a Ghanaian mother and her child, who shared an unusual variant, ORM1 S2(C), found by isoelectric focusing. Three remarkable changes of nucleotide sequence were observed: (1) The two ORM1 alleles, ORMI*S and ORMI*S2(C), had the AGP2 gene-specific sequence at one and three regions, respectively, in exon 5 to intron 5. The variant allele originating from ORMi*S was characterized by a G-to-A transition, resulting in an amino acid change from valine to methionine, which is also detected in ORM1 F2, a form that is common in Europeans. (2) The AGP2 gene of the child, inherited from the father, was duplicated, as revealed by long-range polymerase chain reaction. (3) Three new mutations were observed in two exons of the AGP2 genes of the mother and child. All of these novel genomic rearrangements, which were not observed in Japanese subjects, may have arisen through point mutation, gene conversion, and unequal crossover events. It is likely that the rearrangement of the AGP gene has often occurred in Africans.

Magnetofection: enhancing and targeting gene delivery by magnetic force in vitro and in vivo

Low efficiencies of nonviral gene vectors, the receptor-dependent host tropism of adenoviral or low titers of retroviral vectors limit their utility in gene therapy. To overcome these deficiencies, we associated gene vectors with superparamagnetic nanoparticles and targeted gene delivery by application of a magnetic field. This potentiated the efficacy of any vector up to several hundred-fold, allowed reduction of the duration of gene delivery to minutes, extended the host tropism of adenoviral vectors to nonpermissive cells and compensated for low retroviral titer. More importantly, the high transduction efficiency observed in vitro was reproduced in vivo with magnetic field-guided local transfection in the gastrointestinal tract and in blood vessels. Magnetofection provides a novel tool for high throughput gene screening in vitro and can help to overcome fundamental limitations to gene therapy in vivo.

Peri-implant care of ailing implants with the carbon dioxide laser

One of the many applications for which lasers have been proposed in implant dentistry is for the decontamination process. The purposes of this study were to assess possible alterations in titanium implants in vitro and in vivo by use of the carbon dioxide (CO2) laser and to determine whether new bone formation can occur on previously contaminated implants. In vitro, temperature changes at the bone-titanium implant interface were recorded during use of a CO2 laser-scanning system (Swiftlase). Additionally, the effects of laser irradiation on titanium implants at various power settings were examined. In 6 beagle dogs, a total of 60 implants and bony defects resulting from plaque accumulation were treated by air-powder abrasive (the conventional treatment), laser irradiation, or both. Depending on the parameters chosen, melting and other surface alterations were seen in vitro, especially in the superpulse mode. Otherwise, no alterations were found, even at high power settings in the continuous mode. In vivo, corresponding histologic examination of 4-month sections showed evidence of new direct bone-to-implant contact after laser-assisted therapy, especially when the implants had been treated concomitantly with submerged membranes. These results support the hypothesis that peri-implant defects can be treated successfully by laser decontamination without damaging the surrounding tissues in the dog model. Nevertheless, further investigations will be required to determine the clinical efficacy of the treatment.

Large-scale analysis of the Alu Ya5 and Yb8 subfamilies and their contribution to human genomic diversity

We have utilized computational biology to screen GenBank for the presence of recently integrated Ya5 and Yb8 Alu family members. Our analysis identified 2640 Ya5 Alu family members and 1852 Yb8 Alu family members from the draft sequence of the human genome. We selected a set of 475 of these elements for detailed analyses. Analysis of the DNA sequences from the individual Alu elements revealed a low level of random mutations within both subfamilies consistent with the recent origin of these elements within the human genome. Polymerase chain reaction assays were used to determine the phylogenetic distribution and human genomic variation associated with each Alu repeat. Over 99 % of the Ya5 and Yb8 Alu family members were restricted to the human genome and absent from orthologous positions within the genomes of several non-human primates, confirming the recent origin of these Alu subfamilies in the human genome. Approximately 1 % of the analyzed Ya5 and Yb8 Alu family members had integrated into previously undefined repeated regions of the human genome. Analysis of mosaic Yb8 elements suggests gene conversion played an important role in generating sequence diversity among these elements. Of the 475 evaluated elements, a total of 106 of the Ya5 and Yb8 Alu family members were polymorphic for insertion presence/absence within the genomes of a diverse array of human populations. The newly identified Alu insertion polymorphisms will be useful tools for the study of human genomic diversity.

Plasma epinephrine levels after epinephrine administration using different tracheal administration techniques in an adult CPR porcine model

The aim of the study was to compare arterial plasma epinephrine levels after tracheal epinephrine application using three different tracheal instillation techniques at different tracheal levels in a porcine adult cardiopulmonary resuscitation model. In the prospective, randomized study, electrically-induced cardiopulmonary arrest was applied to 32 anaesthetized and paralyzed domestic pigs. After 3 min of cardiopulmonary arrest and 2 min of external chest compressions using a pneumatic compression device and mechanical ventilation, epinephrine was administered intravenously (20 microg/kg) or tracheally (50 microg/kg): using either direct injection into the upper end of the tracheal tube, via a catheter placed into the bronchial system and using a special tracheal application tube. In each group, there were eight pigs. Arterial blood samples were taken before and up to 10 min after epinephrine administration. Regression analysis was performed of the correlated data. The values of mean arterial blood pressure and end-tidal CO(2) during the time of observation did not differ between groups. Total plasma epinephrine concentrations showed a significant increase in all groups, but with no difference between the tracheal groups. However, peak epinephrine levels in the intravenous group were significantly higher than in tracheal groups. We conclude that administration using three different tracheal instillation levels result in similar onset and peak plasma epinephrine levels in this setting and therefore the preferred method of tracheal epinephrine application for cardiopulmonary resuscitation may be selected by other criteria.

Application of Y-chromosomal STR haplotypes to forensic genetics

This paper delivers population genetic data on Y-chromosomal short tandem repeat (STR) polymorphisms along with reports of unusual observations and casework. Population studies were carried out on the Y-specific STR polymorphisms DYS19, DYS385 I+II, DYS389 I+II, DYS390, DYS391, DYS392, and DYS393 in population samples from North India, Turkey, and Germany. In all three populations the vast majority of haplotypes was observed only once, especially in the Turkish group. Highly unusual cases are reported. In a German individual, we observed the variant allele DYS392*11.1, whereas a Turkish haplotype revealed a duplication at locus DYS19. Application of Y-chromosomal STR markers to forensic genetics was demonstrated in two cases: 1) a deficient paternity case, and 2) a father/son pair, where the Amelogenin primers failed to amplify the Y-homolog. In forensic genetics, Y-chromosomal STR polymorphisms are highly welcomed as an additional tool.

Online reference database of European Y-chromosomal short tandem repeat (STR) haplotypes

The reference database of highly informative Y-chromosomal short tandem repeat (STR) haplotypes (YHRD), available online at http://ystr.charite.de, represents the largest collection of male-specific genetic profiles currently available for European populations. By September 2000, YHRD contained 4688 9-locus (so-called "minimal") haplotypes, 40% of which have been extended further to include two additional loci. Establishment of YHRD has been facilitated by the joint efforts of 31 forensic and anthropological institutions. All contributing laboratories have agreed to standardize their Y-STR haplotyping protocols and to participate in a quality assurance exercise prior to the inclusion of any data. In view of its collaborative character, and in order to put YHRD to its intended use, viz. the support of forensic caseworkers in their routine decision-making process, the database has been made publicly available via the Internet in February 2000. Online searches for complete or partial Y-STR haplotypes from evidentiary or non-probative material can be performed on a non-commercial basis, and yield observed haplotype counts as well as extrapolated population frequency estimates. In addition, the YHRD website provides information about the quality control test, genotyping protocols, haplotype formats and informativity, population genetic analysis, literature references, and a list of contact addresses of the contributing laboratories.

Diagnosing acute liver graft rejection: experimental application of an implantable telemetric impedance device in native and transplanted porcine livers

BACKGROUND AND AIMS

Diagnosis of acute rejection is a complex and persistent problem in liver transplantation. Focused on the use of proprietary impedance technology a porcine liver model was designed to provide immediate information for differentiation of normal and acute rejecting tissue by an implantable telemetric device.

METHODS

Electrical impedance was analyzed by electrodes implanted in vitro and in vivo in the liver of pigs, where impedance is derived from measurements of voltage transients produced in response to programmed current pulses. Consequent electric recordings in porcine livers after transplantation and after mere laparotomy were evaluated in relation to biochemical parameters and histological results of liver biopsies.

RESULTS

Acute rejection was correctly predicted in all cases and correctly excluded in the remaining 32 biopsy related impedance recordings (P<0.004). Impedance measurements not only correlated with the diagnosis from liver biopsy specimen (r=0.84, P<0.0001) but also exemplified the severity of histological acute rejection.

CONCLUSION

Impedance analysis reveals evident physiologic relation of acute liver graft rejection and electrical organ properties. Electrodes implanted in transplanted porcine livers allow running less invasive monitoring and thus early detection of rejection. The technology may have broad value in providing an immediate diagnosis of acute rejection, reducing unnecessary patient anxiety and eliminating the significant expenses associated with multiple referrals, expensive sample handling and tissue analysis.

Molecular analysis of the human orosomucoid gene ORM1*Q0köln responsible for incompatibility in a German paternity case

In a German paternity test, an alleged father was excluded only by reverse homozygosity of ORM1 phenotypes (mother ORM1 S, child ORM1 S and alleged father ORM1 F1) out of the 28 classical and DNA markers investigated. Without the ORM1 system the biostatistical probability of paternity was calculated to exceed 99.999%. The intensity of the immunoprinted bands of the ORM1 protein for the child and alleged father after isoelectric focusing appeared to be reduced to about half. To identify a possible null allele, gene-specific amplification followed by single-strand conformation polymorphism and sequencing analyses were carried out. Deletion of one of the two copies of a 4 bp direct repeat sequence (GTCT) in exon 4 of the consensus sequence of ORM1*F1 was observed in the child and alleged father. Thus, the sharing of a rare mutant gene, ORM1*Q0köln, increased the probability of paternity.

Sequence analysis and population data on the 'new' short tandem repeat locus D5S2360

We have studied the sequence structure and population genetics of a 'new' short tandem repeat polymorphism at locus D5S2360 in German Caucasians. Sequencing at this locus revealed a considerable variation, which is characterized by a tetranucleotide (AGAT)(n) repeat pattern with (GAT), (AGATT), and (AG) repeats dispersed throughout the alleles. These microvariations do not necessarily alter the size of the alleles. They may vary by one or two pairs or they may remain unchanged in size. At locus D5S2360 we observed 33 allelic lengths comprising at least 36 different alleles. Population data revealed a high polymorphism with a heterozygosity rate of approximately 92.5%.

Haplotype analysis of the human alpha2-HS glycoprotein (fetuin) gene

Alpha2-HS glycoprotein (AHSG), which is equivalent to fetuin in other species, is a protein found in human plasma. AHSG is polymorphic with two common alleles and many variants. To examine the intragenic haplotypes and their diversity at this locus, a contiguous genomic DNA sequence (10.3 kb) was analyzed in 20 samples (40 chromosomes), and haplotypes were determined for 309 subjects. Judging from the aligned nucleotide sequences and the conserved amino acid residues comparing human and chimpanzee AHSG, it was concluded that the type 1 allele is probably older and has evolved into four major suballeles. The type 2 allele was generated from one branch of the type 1 allele. AHSG*3 and *5 variants were each found to have a single nucleotide change in exon 7, resulting in the change of an amino acid residue from Arg299 to Cys and from Asp258 to Asn, respectively. It was noted that the AHSG*3 mutation gives rise to an additional cysteine residue, which possibly affects the conformation of the protein. The AHSG gene was found to have a low mutation rate and no apparent recombination events. Furthermore, the detected substitutions were nonhomogeneously distributed at this locus. In particular, four nonsynonymous substitutions were concentrated in the carboxyl-terminal domain.

Acute electrophysiologic effects and antifibrillatory actions of the long linear lesions in the right atrium in a sheep model

Linear lesions (LL) represent an option for curing of atrial fibrillation (AF) with ablation techniques.

METHODS AND RESULTS

In 11 sheep (w. 72+/-16 kg), LL were created with radiofrequency ablation in the lateral, posterior and septal walls of the right atrium (RA). AF was induced before and after LL with burst pacing. Mapping of the AF was performed with a 64-electrode basket catheter deployed in the RA. Quantitative analysis was performed with a custom-made software program. LL were confirmed histologically 7 to 10 days after the procedure. LL were transmural in 78% of their length. Stimulation thresholds and right atrial activation times were increased after LL compared to preablation values. Effective refractory periods of the RA were prolonged significantly in 7 out of 12 regions after generation of LL. Conduction velocities in the RA segments between LL were reduced in lateral, posterior and septal walls. During paced rhythms double potentials were recorded in all animals. AF could be induced in all animals of this model despite the presence of LL in the RA. AF episodes were significantly more regular after LL throughout the RA due to a significant reduction of the number of the wave fronts in the RA. During AF episodes, in the presence of LL, the RA was driven by wave fronts of left atrial origin entering the right side of the septum through interatrial connections.

CONCLUSIONS

1) LL profoundly affect electrophysiologic parameters of RA. 2) In the presence of LL, AF manifest a higher degree of regularity as compared to preablation episodes. 3) Dissociation between wave fronts of left atrial origin entering the RA through the interatrial connections is an important mechanism of the antifibrillatory action of the septal LL.

Human autosomal short tandem repeat types in Jat Sikhs from North India

This study provides Jat Sikhs population data in North India for nine short tandem repeat (STR) loci.

Malignant hyperthermia mutation Arg615Cys in the porcine ryanodine receptor alters voltage dependence of Ca2+ release

Ca2+ inward current and fura-2 Ca2+ transients were simultaneously recorded in porcine myotubes. Myotubes from normal pigs and cells from specimens homozygous for the Arg615Cys (malignant hyperthermia) mutation of the skeletal muscle ryanodine receptor RyR1 were investigated. We addressed the question whether this mutation alters the voltage dependence of Ca2+ release from the sarcoplasmic reticulum. The time course of the total flux of Ca2+ into the myoplasm was estimated. Analysis showed that the largest input Ca2+ flux occurred immediately after depolarization. Amplitude and time course of the Ca2+ flux at large depolarizations were not significantly different in the Arg615Cys myotubes. Ca2+ release from the sarcoplasmic reticulum was activated at more negative potentials than the L-type Ca2+ conductance. In the controls, the potentials for half-maximal activation V 1/2 were -9.0mV and 16.5 mV, respectively. In myotubes expressing the Arg615Cys mutation, Ca2+ release was activated at significantly lower depolarizing potentials (V = -23.5 mV) than in control myotubes. In contrast, V of conductance activation (13.5 mV) was not significantly different from controls. The specific shift in the voltage dependence of Ca2+ release caused by this mutation can be well described by altering a voltage-independent reaction of the ryanodine receptor that is coupled to the voltage-dependent transitions of the L-type Ca2+ channel.

Predictors of cigarette smoking and smoking cessation among adults with asthma

OBJECTIVES

This study sought to determine the predictors of smoking and time until smoking cessation in a cohort of adults with asthma.

METHODS

Adults with asthma (n = 374) in northern California completed structured telephone interviews at baseline and 18-month follow-up.

RESULTS

Of the 374 subjects, 156 reported ever having smoked, and 39 indicated that they currently smoked. Earlier birth cohort, lower educational attainment. White race, and presence in childhood residence of an adult who smoked were associated with a greater risk of ever smoking. Lower educational attainment, early smoking initiation, higher daily cigarette consumption, and late-childhood-onset asthma were associated with a longer interval until smoking cessation.

CONCLUSIONS

Persons with asthma at high risk of cigarette smoking and delayed quitting can be identified on the basis of clinical and demographic characteristics.

Characteristics and frequency of germline mutations at microsatellite loci from the human Y chromosome, as revealed by direct observation in father/son pairs

A number of applications of analysis of human Y-chromosome microsatellite loci to human evolution and forensic science require reliable estimates of the mutation rate and knowledge of the mutational mechanism. We therefore screened a total of 4,999 meioses from father/son pairs with confirmed paternity (probability >/=99. 9%) at 15 Y-chromosomal microsatellite loci and identified 14 mutations. The locus-specific mutation-rate estimates were 0-8. 58x10-3, and the average mutation rate estimates were 3.17x10-3 (95% confidence interval [CI] 1.89-4.94x10-3) across 8 tetranucleotide microsatellites and 2.80x10-3 (95% CI 1.72-4.27x10-3) across all 15 Y-chromosomal microsatellites studied. Our data show a mutational bias toward length increase, on the basis of observation of more repeat gains than losses (10:4). The data are in almost complete agreement with the stepwise-mutation model, with 13 single-repeat changes and 1 double-repeat change. Sequence analysis revealed that all mutations occurred in uninterrupted homogenous arrays of >/=11 repeats. We conclude that mutation rates and characteristics of human Y-chromosomal microsatellites are consistent with those of autosomal microsatellites. This indicates that the general mutational mechanism of microsatellites is independent of recombination.