Involvement of the prostate and testis expression (PATE)-like proteins in sperm-oocyte interaction

BACKGROUND

The prostate and testis expression (PATE)-like family of proteins are expressed mainly in the male genital tract. They are localized in the sperm head and are homologous to SP-10, the acrosomal vesicle protein also named ACRV1. Our aim was to characterize the expression and functional role of three PATE-like proteins in the testis and ejaculated sperm.

METHODS

The expression and localization of PATE-like proteins in human testis biopsies (n= 95) and sperm cells were assessed by RT-PCR, immunohistochemistry and immunofluorescence staining (at least 600 sperm cells per specimen). The function of the PATE protein was tested by the hemizona assay and hamster egg penetration test (HEPT).

RESULTS

PATE and PATE-M genes and proteins were present almost exclusively in germ cells in the testis: immunoflourescence showed that the percentage of germ cells positive for PATE, PATE-M and PATE-B was 85, 50 and 2%, respectively. PATE and PATE-M proteins were localized in the equatorial segment of the sperm head, while PATE-B protein was localized in the post-acrosomal region. A polyclonal antibody (Ab, at 1:50 and 1:200 dilutions) against the PATE protein did not inhibit sperm-zona binding in the hemizona assay (hemizona index of 89.6 ± 10 and 87 ± 36%, respectively). However, there was inhibition of sperm-oolemma fusion and penetration in the HEPT (penetration index: without Ab 7 ± 3.9; Ab dilution of 1:100, 4 ± 3.5; Ab dilution of 1:20, 0.6 ± 1.2, P < 0.001).

CONCLUSIONS

Our data suggest that PATE protein is involved in sperm-oolemma fusion and penetration but not sperm-zona binding.

[Distance from the laryngeal mask grip to endotracheal tube tip. A crucial point during fiberoptic intubation in children]

BACKGROUND

Management of difficult airways and difficult intubation differs in pediatric and in adult patients. In conscious children, fiberoptic intubation is not feasible because of limited compliance. The specially designed laryngeal mask for blind tracheal intubation, LMA Fastrach™, is available for adolescents and adults only. Therefore, fiberoptic-guided intubation through a supraglottic airway device (SAD) is a standard technique for the management of difficult intubation in children. While performing the procedure, stabile positioning of the endotracheal tube (ETT) and prevention of dislodgement are critical issues. The relationship between the length of the ETT and the SAD is highly important and was investigated in this in vitro study.

MATERIALS AND METHODS

In this study 6 different brands of SAD in the pediatric sizes 1-3 and 2 different ETT brands (cuffed, Microcuff(®), uncuffed, Sheridan PED-SOFT™) were investigated. Using pediatric growth tables, the recommended patient weight for each SAD size was correlated to patient age and then to appropriately sized cuffed and uncuffed ETTs. The ETT size was chosen according to the manufacturer's recommendations (cuffed ETT) and according to the literature (uncuffed ETT). The various SAD-ETT pairs were assessed with regard to differences in their length. After lubrication with silicone the ETT with a firmly attached 15 mm tube adapter was maximally inserted into the SAD and the ETT tip overlapping the SAD cuff was measured. Secondarily, an adapter for fiberoptic procedures was interposed and the measurements repeated.

RESULTS

For a defined patient uncuffed ETTs were usually selected with a larger internal diameter (ID) compared to cuffed ETTs. Therefore, the uncuffed ETT is the longer one and will overlap the SAD by a longer tip. Comparing the curved SAD brands AuraOnce™ and Aura-i™, the Aura-i™ devices generally showed shorter tubes resulting in a longer protruding ETT tip (median 1.5 cm, minimum-maximum 1.0-2.4 cm). The straight brands LMA classic™, AuraStraight™ and LMA Unique™ showed similarity in tube length. In comparison with i-gel(®), for the SAD sizes 1-2.5 the former provide a longer projecting ETT tip. Only i-gel(®) together with AuraStraight™ showed the longest overlapping ETT tip for SAD size 3. If a swivel adapter was used during the fiberoptic intubation procedure, the length of the ETT could be critically reduced in relation to the length of the SAD. Using a swivel adapter from VBM Medizintechnik, (Sulz a. N., Germany) a relative reduction in ETT length of 2.3 or 3.2 cm has to be taken into account.

CONCLUSIONS

For fiberoptic-guided endotracheal intubation through an SAD, sufficient length of the ETT in relation to the SAD is mandatory. Differences in geometry between SAD and ETT brands have to be considered. The selection of a relatively small SAD in combination with an uncuffed ETT might be advantageous. Redesigned extra long ETTs would be desirable to decrease the risk for ETT dislocation and to increase the safety of the technique. Restrictive use of a swivel adapter during the procedure is important because of further and potentially critical decreases in ETT length. In addition, after successful intubation of the trachea, removal of the SAD via an airway exchange catheter and replacement of the cuffed ETT of choice in the correct position is recommended to secure the airway and provide unimpaired ventilation and oxygenation.

Spontaneously gapped ground state in suspended bilayer graphene

Bilayer graphene bears an eightfold degeneracy due to spin, valley, and layer symmetry, allowing for a wealth of broken symmetry states induced by magnetic or electric fields, by strain, or even spontaneously by interaction. We study the electrical transport in clean current annealed suspended bilayer graphene. We find two kinds of devices. In bilayers of type B1 the eightfold zero-energy Landau level is partially lifted above a threshold field revealing an insulating ν=0 quantum-Hall state at the charge neutrality point. In bilayers of type B2 the Landau level lifting is full and a gap appears in the differential conductance even at zero magnetic field, suggesting an insulating spontaneously broken symmetry state. Unlike B1, the minimum conductance in B2 is not exponentially suppressed, but remains finite with a value G is < or approximately equall to e(2)/h even in a large magnetic field. We suggest that this phase of B2 is insulating in the bulk and bound by compressible edge states.

Myocardial pharmacokinetics of ebastine, a substrate for cytochrome P450 2J, in rat isolated heart

BACKGROUND AND PURPOSE

It is well established that cytochrome P450 2J (CYP2J) enzymes are expressed preferentially in the heart, and that ebastine is a substrate for CYP2J, but it is not known whether ebastine is metabolized in myocardium. Therefore, we investigated its pharmacokinetics in the rat isolated perfused heart.

EXPERIMENTAL APPROACH

Rat isolated hearts were perfused in the recirculating mode with ebastine for 130 min. The concentrations of ebastine and its metabolites, hydroxyebastine and carebastine, were measured using liquid chromatography with a tandem mass spectrometry. The data were analysed by a compartmental model. The time course of negative inotropic response was linked to ebastine concentration to determine the concentration-effect relationship.

KEY RESULTS

Ebastine was metabolized to an intermediate compound, hydroxyebastine, which was subsequently further metabolized to carebastine. No desalkylebastine was found. The kinetics of the sequential metabolism of ebastine was well described by the compartmental model. The EC(50) of the negative inotropic effect of ebastine in rat isolated heart was much higher than free plasma concentrations in humans after clinical doses.

CONCLUSIONS AND IMPLICATIONS

The kinetics of ebastine conversion to carebastine via hydroxyebastine resembled that observed in human liver microsomes. The results may be of interest for functional characterization of CYP2J activity in rat heart.

In-line filter included into the syringe infusion pump assembly reduces flow irregularities

PURPOSE

To evaluate whether an in-line filter inserted in the syringe pump infusion line assembly influences start-up times and flow irregularities during vertical pump displacement at low infusion rates.

METHODS

Fluid delivery after syringe pump start-up and after vertical displacement of the syringe pump by -50 cm was determined gravimetrically at flow rates of 0.5, 1.0 and 2.0 ml h(-1). Measurements were repeated for each flow rate four times with two different syringe pumps with and without an in-line filter incorporated. Data are shown as median and range.

RESULTS

Start-up times were reduced by an in-line filter at 0.5 ml h(-1) flow rate from 355.5 s (0-660) to 115 s (0-320), whereas the effect was attenuated at higher flow rates. Pooling of fluid into the infusion system after lowering the infusion syringe pump was halved in all flow rates tested. Amount of infusion bolus after elevating the syringe pump by 50 cm was not affected by an in-line filter.

CONCLUSION

In the evaluated model in-line filters help to reduce flow irregularities and delay in drug delivery of syringe pumps at low flow rates and represent an option to optimize continuous administration of highly concentrated short-acting drugs at very small infusion rates.

Comparison of thromboelastometry (ROTEM®) with standard plasmatic coagulation testing in paediatric surgery

BACKGROUND

Thromboelastometry (ROTEM(®)) might be useful to detect intraoperative coagulation disorders early in major paediatric surgery. This observational trial compares this technique to standard coagulation tests.

METHODS

Intraoperative blood sampling was obtained in children undergoing elective major surgery. At each time point, standard coagulation tests [activated partial thromboplastin time (aPTT), prothrombin time (PT), and fibrinogen level] and ROTEM(®) analyses (InTEM, ExTEM, and FibTEM) were performed simultaneously by trained hospital laboratory staff.

RESULTS

A total of 288 blood samples from 50 subjects were analysed. While there was a poor correlation between PT and aPTT to ExTEM clotting time (CT) and InTEM CT, respectively, a good correlation was detected between PT and aPTT to clot formation time, and a very good correlation between fibrinogen level and FibTEM assay (r=0.882, P<0.001). Notably, 64% of PT and 94% of aPTT measurements were outside the reference range, while impaired CT was observed in 13% and 6.3%, respectively. Standard coagulation test results were available after a median of 53 min [inter-quartile range (IQR): 45-63 min], whereas 10 min values of ROTEM(®) results were available online after 23 min (IQR: 21-24 min).

CONCLUSIONS

PT and aPTT cannot be interchangeably used with ROTEM(®) CT. Based on the results of ROTEM(®), recommended thresholds for PT and aPTT might overestimate the need for coagulation therapy. A good correlation was found between the fibrinogen level and the FibTEM assay. In addition, ROTEM(®) offered faster turnaround times.

Cardiac risk assessment before the use of stimulant medications in children and youth

Regulatory decisions and scientific statements regarding the management of attention-deficit hyperactivity disorder (ADHD) raise questions about the safety of medications and the appropriate pretreatment evaluation to determine suitability for treatment with medication. This is particularly true in the setting of known structural or functional heart disease. The present paper reviews the available data, including peer-reviewed literature, data from the United States Food and Drug Administration Web site on reported adverse reactions in children using stimulant medication, and Health Canada data on the same problem. A consensus-based guideline on appropriate assessment is provided, based on input from members of the Canadian Paediatric Society, the Canadian Cardiovascular Society and the Canadian Academy of Child and Adolescent Psychiatry, with specific expertise and knowledge in the areas of both ADHD and paediatric cardiology. The present statement advocates a thorough history and physical examination before starting stimulant medications, with an emphasis on the identification of risk factors for sudden death, but does not routinely recommend electrocardiographic screening or cardiac sub-specialist consultation unless indicated by history or physical examination findings. A checklist for identifying children who are potentially at risk of sudden death (independent of ADHD or medications used to treat it) is provided. Although recommendations are based on the best evidence currently available, the committee further agrees that more research on this subject is necessary to optimize the approach to this common clinical scenario.

Gate-tunable split Kondo effect in a carbon nanotube quantum dot

We show a detailed investigation of the split Kondo effect in a carbon nanotube quantum dot with multiple gate electrodes. Two conductance peaks, observed at finite bias in nonlinear transport measurements, are found to approach each other for increasing magnetic field, to result in a recovered zero bias Kondo resonance at finite magnetic field. Surprisingly, in the same charge state, but under different gate configurations, the splitting does not disappear for any value of the magnetic field, but we observe an avoided crossing. We think that our observations can be understood in terms of a two-impurity Kondo effect with two spins coupled antiferromagnetically. The exchange coupling between the two spins can be influenced by a local gate, and the non-recovery of the Kondo resonance for certain gate configurations is explained by the existence of a small antisymmetric contribution to the exchange interaction between the two spins.

Closed tracheal suction and fluid aspiration past the tracheal tube. Impact of tube cuff and airway pressure

BACKGROUND

This study investigated the effect of different tube cuff types and airway pressures on fluid leakage past the tracheal tube cuff during suction with a closed tracheal suction system (CTSS).

METHODS

Unlubricated high-volume, low-pressure tracheal tube cuffs made from polyvinylchloride (PVC) and polyurethane (PU) with a size 7.5 mm internal diameter (ID) were placed in a 22 mm ID artificial trachea connected to a test lung and inflated to 25 or 50 cmH2O of cuff pressure. Positive pressure ventilation (PPV) with peak inspiratory pressures of 15, 20 or 25 cmH2O and positive end expiratory pressures (PEEP) of 5 or 10 cmH2O were used. A CTSS catheter (14 Fr) was attached to the tracheal tube and suction was performed for 5, 10, 15 or 20 s with 200 or 300 cmH2O of negative suction pressures. The volume of fluid leaking across the tube cuff at the end of the suction procedure was measured (mL), and the airway pressure was simultaneously recorded. Fluid leakage and airway pressures during different suction conditions were compared using a Kruskal Wallis test and Mann Whitney test (P<0.05).

RESULTS

The airway pressure drop during suction was similar for both tube cuffs. The PU tube cuff resulted in significantly less fluid leakage (range 0.00-0.12 mL) than the PVC tube cuff (P<0.001). For the PVC tube cuff, fluid leakage at higher cuff pressures was significantly less (P<0.01).Varying PEEP and PIP did not change the fluid leakage or the drop in airway pressure.

CONCLUSION

The use of PU tube cuffs and intermittent transient increases in cuff pressure during suction can effectively reduce fluid leakage past the tracheal tube during closed tracheal suctioning.

A review of recent neurochemical data on inert gas narcosis

Nitrogen narcosis occurs in humans at around 0.4 MPa (4 ATA). Hydrogen narcosis occurs between 2.6 and 3.0 MPa. In rats, nitrogen disturbances occur from 1 MPa and a loss of righting reflex around 4 MPa. Neurochemical studies in striatum of rats with nitrogen at 3 MPa (75% of anesthesia threshold) with differential pulse voltammetry have demonstrated a decrease in dopamine (DA) release by neurons originated from the substantia nigra pars compacta (SNc). Such a decrease is found also with compressed argon, which is more narcotic than nitrogen and with the anesthetic gas nitrous oxide. Inversely, compressed helium with its very low narcotic potency induces DA increase. Microdialysis studies in the striatum have indicated that nitrogen also induces a decrease of glutamate concentration. Nitrogen pressure did not modify NMDA glutamate receptor activities in SNc or striatum but enhanced GABAA receptors activities in SNc. Repetitive exposures to nitrogen narcosis suppressed the DA decrease and induced an increase. This fact and the lack of improvement of motor disturbances did not support the hypothesis of a physiological adaptation. The desensitization of the GABAA receptors on DA cells during recurrent exposures and the parallel long-lasting decrease of glutamate coupled to the increase in NMDA receptor sensitivity suggest a nitrogen neurotoxicity or addiction induced by recurrent exposures. The differential changes produced by inert gases indifferent neurotransmitter receptors would support the binding protein theory.

CMT2C with vocal cord paresis associated with short stature and mutations in the TRPV4 gene

BACKGROUND

Recently, mutations in the transient receptor potential cation channel, subfamily V, member 4 gene (TRPV4) have been reported in Charcot-Marie-Tooth Type 2C (CMT2C) with vocal cord paresis. Other mutations in this same gene have been described in separate families with various skeletal dysplasias. Further clarification is needed of the different phenotypes associated with this gene.

METHODS

We performed clinical evaluation, electrophysiology, and genetic analysis of the TRPV4 gene in 2 families with CMT2C.

RESULTS

Two multigenerational families had a motor greater than sensory axonal neuropathy associated with variable vocal cord paresis. The vocal cord paresis varied from absent to severe, requiring permanent tracheotomy in 2 subjects. One family with mild neuropathy also manifested pronounced short stature, more than 2 SD below the average height for white Americans. There was one instance of dolichocephaly. A novel S542Y mutation in the TRPV4 gene was identified in this family. The other family had a more severe, progressive, motor neuropathy with sensory loss, but less remarkable short stature and an R315W mutation in TRPV4. Third cranial nerve involvement and sleep apnea occurred in one subject in each family.

CONCLUSION

CMT2C with axonal neuropathy, vocal cord paresis, and short stature is a unique syndrome associated with mutations in the TRPV4 gene. Mutations in TRPV4 can cause abnormalities in bone, peripheral nerve, or both and may result in highly variable orthopedic and neurologic phenotypes.

[Intraosseous infusion in the pediatric emergency medical service. Analysis of emergency medical missions 1990-2009]

BACKGROUND

Timely establishment of venous access in infants and toddlers during emergency medical care can be a particularly challenging task. Alternative routes for drug and fluid administration, such as endobronchial, intramuscular, central venous or venous cut-down do not offer reliable solutions. Intraosseous infusion (IOI) has become established as an effective alternative intravascular access for rapid and efficient drug delivery. IOI was introduced in our local emergency medical service (EMS) in 1993 and was assigned a high priority in international guidelines for pediatric emergency medical care in 2000 and 2005. The aim of this study was to review the impact of the introduction of IOI on drug administration routes during prehospital emergency treatment of critically ill or severely injured pediatric patients (NACA index V-VII) in our tertiary medical care centre over a period of 20 years.

METHODS

Pediatric prehospital emergency medical protocols from 1990 to 2009 were analyzed with respect to the administration routes for fluids and medications in severely injured or critically ill children with NACA severity scores V-VII. The frequency and mode of vascular access during prehospital treatment including IOI, endobronchial administration, central venous catheterization (CVC) and intramuscular administration as well as prehospital treatment and transportation without vascular access were analyzed. Two groups were compared: the introduction phase of IOI between 1990 and 1999 and the phase of growing IOI routine after introducing guidelines and regular staff IOI technique training between 2000 and 2009. Demographic data and drug administration routes in the two different time periods were analyzed using the Mann-Whitney-u test and t-test or χ(2)-test, respectively. A p-value <0.05 was regarded as significant.

RESULTS

A total of 5,279 pediatric prehospital emergency charts were analyzed and 401 patients (7.6%) were scored as NACA V-VII. At the emergency scene 299 patients (75%) received a peripheral intravenous access, 3 (0.7%) a central venous line access, 77 (19%) an intraosseous needle and in 22 (5.4%) no vascular or intraosseous access was used during the course of prehospital treatment (NACA VII - 13 patients, NACA VI - 2 patients, NACA V - 7 patients). Of the NACA VII patients 3 were transported under continuous cardiopulmonary resuscitation without vascular access. After 2002 all patients with NACA index VII were treated with vascular or intraosseous access. In 48 patients (12%) at least initial medication was given by the endobronchial or alternative route but within the last 3 years endobronchial drug administration was no longer reported. Thus, in 124 critically ill patients (31%) routine peripheral venous access could not be established initially or until the end of treatment (77 times IOI, 22 times no access over the course of treatment, 3 times CVC and 22 times initial endobronchial followed by peripheral venous access). Over the reviewed period the use of IOI increased significantly (p<0.001), while the incidence of lacking vascular access (p<0.05) and alternative drug administration routes (p<0.001) continuously decreased.

CONCLUSION

The IOI technique has not only been assigned a high priority in the guidelines for pediatric emergency care of critically ill children with difficult or failed venous access but has also significantly influenced current prehospital care. The introduction of the IOI technique in our prehospital pediatric emergency system has markedly reduced the number of critically ill or severely injured pediatric patients without vascular access or with less reliable alternative administration routes in the last 20 years.

Acute postinfectious glomerulonephritis associated with Campylobacter jejuni enteritis - a case report and review of the literature on C. jejuni's potential to trigger immunologically mediated renal disease

Kidney disease is a rare complication of Campylobacter jejuni (C. jejuni) enteritis. We here present the case of an 18-year-old male patient with crampy abdominal pain, vomiting, diarrhea, and fever. Three weeks later urinalysis revealed mild proteinuria and hematuria and a marked raise in serum creatinine was observed. Renal biopsy demonstrated acute endocapillary glomerulonephritis with mesangial IgM (immunoglobuline M) deposits. Extensive workup revealed no signs of skin or joint disease, thus excluding Henoch-Schönlein purpura. Due to persistent abdominal discomfort further gastro-enterological tests were performed and eventually Campylobacter jejuni was isolated from the patient's feces. In the absence of other precipitating factors for renal diseases we presumed an association between the bacterial infection and this postinfectious glomerulonephritis. Over a time period of 6 months the patient's kidney function normalized completely. However, long-term prognosis remains unclear. In addition to the case report, we conducted a review of the literature with results underlining Campylobacter jejuni's potential to trigger various types of immune mediated kidney diseases.

[Clinical ecomomics: a pleading for complementing the medical curriculum and specialty training]

Clinical economics requires an understanding of clinical relationships just like health economy requires an understanding of economic relationships. Hitherto we have ensured that economists can differentiate symptoms from diagnoses and diagnostics from screening at the interface between medicine and economy. However, we overlooked the fact that physicians should be able to understand the principles of marginal benefit and medical ethics, as well as the differences among efficacy, effectiveness, and benefit, to be able to make sound decisions. To make up for this neglected demand, we present our definition of clinical economics, identify the potential conflicts between medical professionalism and commercialized medicine, describe the importance - but also the limits - of scientific evidence, explain the difference between 'prioritization' and strict rationing, and attempt to justify the fact that the necessary changes in the provision of healthcare will probably only be achieved if we instill this new way of thinking in medical students during their medical education. Complementing the medical curriculum with clinical economics would achieve this goal.

[Intrathecal opioid medication for perioperative analgesia in severely handicapped children undergoing spinal operations]

PURPOSE OF THE STUDY

Intrathecal opioids have been shown to be safe and effective for postoperative analgesia in healthy children for spinal surgery. The aim of this study was to evaluate the applicability of intrathecal opioids in severely handicapped children scheduled for spinal surgery.

METHODS

With hospital ethical committee approval, patients with physical states III and IV of the ASA classification requiring spinal surgery were retrospectively studied. In addition to inhalational anesthesia with sevoflurane or intravenous anesthesia using propofol, morphine 20 microg/kgBW and sufentanil 1.5 microg/kgBW were administered intrathecally before surgery. After surgery an infusion of nalbuphine was started. Need for additional intraoperative and postoperative analgesics, time of extubation, postoperative pain scores and p(a)CO2 values as well as adverse effects were recorded.

RESULTS

A total of 28 patients aged from 2.8 to 18.5 years (median 11.6 years) were studied. Immediate tracheal extubation in the operating room was possible in 17 patients and for 11 patients delayed extubation was elected. All patients were extubated within 24 h except for 1 patient who received massive postoperative transfusions. In 26 out of 28 patients (93%) the combination of intrathecal opioids with postoperative nalbuphine provided adequate analgesia. Observed side effects were post-operative nausea and vomiting (PONV), pruritus and moderate hypoventilation. In two patients a change to intravenous morphine therapy was necessary.

CONCLUSION

The use of intrathecal opioids for perioperative pain control from spinal fusion in severely handicapped children is feasible. Intrathecal opioids provide adequate postoperative analgesia and allow early extubation without persisting relevant respiratory compromise in most of these patients.

Thromboelastometry (ROTEM) in children: age-related reference ranges and correlations with standard coagulation tests

BACKGROUND

The small sample volume needed and the prompt availability of results make viscoelastic methods like rotational thromboelastometry (ROTEM) attractive for monitoring coagulation in small children. However, data on reference ranges for ROTEM parameters in children are scarce.

METHODS

Four hundred and seven children (ASA I and II) undergoing elective surgery were recruited for this prospective, two-centre, observational study. Subjects were grouped as follows: 0-3, 4-12, 13-24 months, 2-5, 6-10, and 11-16 yr. Study objectives were to establish age-dependent reference ranges for ROTEM assays, analyse age dependence of parameters, and compare ROTEM data with standard coagulation tests.

RESULTS

Data from 359 subjects remained for final analysis. Except for extrinsically activated clot strength and lysis, parameters for ROTEM assays were significantly different among all age groups. The most striking finding was that subjects aged 0-3 months exhibited accelerated initiation (ExTEM coagulation time: median 48 s, Q1-Q3 38-65 s; P=0.001) and propagation of coagulation (α angle: median 78(o), Q1-Q3 69-84(o); P<0.001) and maximum clot firmness (median 62 mm, Q1-Q3 54-74 mm), although standard plasma coagulation test results were prolonged (prothrombin time: median 13.2 s, Q1-Q3 12.6-13.6 s; activated partial thromboplastin time: median 42 s, Q1-Q3 40-46 s). Lysis indices of <85% were observed in nearly one-third of all children without increased bleeding tendency. Platelet count and fibrinogen levels correlated significantly with clot strength, and fibrinogen levels correlated with fibrin polymerization.

CONCLUSIONS

Reference ranges for ROTEM assays were determined for all paediatric age groups. These values will be helpful when monitoring paediatric patients and in studies of perioperative coagulation in children.

Modern nuclear medicine evaluation of neuroblastoma

The neuroblastoma is an embryonic tumor of the peripheral sympathetic nervous system, and is metastatic or otherwise high risk for relapse in nearly 50% of cases, with a long-term survival of <40%. Therefore, exact staging with radiological and nuclear medicine imaging methods is crucial for finding the adequate therapeutic choice. The tumor cells express the norepinephrine transporter, which makes metaiodobenzylguanidine (MIBG), an analogue of norepinephrine, an ideal tumor specific agent for imaging. On the other hand, MIBG imaging has several disadvantages as limited spatial resolution, limited sensitivity in small lesions, need for two or even more acquisition sessions, and a delay between the start of the examination and result. Most of these limitations can be overcome with positron emission tomography (PET) using different radiotracers. Furthermore, MIBG imaging is not sufficient for operative or biopsy planning. With this regard, a combination with morphological imaging methods is indispensable. This article will discuss the therapeutic strategy for primary and follow-up diagnosis in neuroblastoma using different nuclear medicine and radiological imaging methods as well as multimodality imaging.

Cuffed endotracheal tubes in children reduce sevoflurane and medical gas consumption and related costs

BACKGROUND

This study aims to evaluate sevoflurane and anaesthetic gas consumption using uncuffed vs. cuffed endotracheal tubes (ETT) in paediatric surgical patients.

METHODS

Uncuffed or cuffed ETT were used in paediatric patients (newborn to 5 years) undergoing elective surgery in a randomized order. Duration of assessment, lowest possible fresh gas flow (minimal allowed FGF: 0.5 l/min) and sevoflurane concentrations used were recorded. Consumption and costs for sevoflurane and medical gases were calculated.

RESULTS

Seventy children (35 uncuffed ETT/35 cuffed ETT), aged 1.73 (0.01-4.80) years, were enrolled. No significant differences in patient characteristics, study period and sevoflurane concentrations used were found between the two groups. Lowest possible FGF was significantly lower in the cuffed ETT group [1.0 (0.5-1.0) l/min] than in the uncuffed ETT group [2.0 (0.5-4.3) l/min], P<0.001. Sevoflurane consumption per patient was 16.1 (6.4-82.8) ml in the uncuffed ETT group and 6.2 (1.1-14.9) ml in the cuffed ETT group, P=0.003. Medical gas consumption was 129 (53-552) l in the uncuffed ETT group vs. 46 (9-149) l in the cuffed ETT group, P<0.001. The total costs for sevoflurane and medical gases were 13.4 (6.0-67.3)euro/patient in the uncuffed ETT group and 5.2 (1.0-12.5)euro/patient in the cuffed ETT group, P<0.001.

CONCLUSIONS

The use of cuffed ETT in children significantly reduced the costs of sevoflurane and medical gas consumption during anaesthesia. Increased costs for cuffed compared with uncuffed ETT were completely compensated by a reduction in sevoflurane and medical gas consumption.

Ganglioside synthase knockout in oncogene-transformed fibroblasts depletes gangliosides and impairs tumor growth

Biologically active membrane gangliosides, expressed and released by many human tumors, are hypothesized to significantly impact tumor progression. Lack of a model of complete and specific tumor ganglioside depletion in vivo, however, has hampered elucidation of their role. Here we report the creation of a novel, stable, genetically induced tumor cell system resulting in specific and complete blockade of ganglioside synthesis. Wild type (WT) and GM3 synthase/GM2 synthase double knockout (DKO) murine embryonic fibroblasts were transformed using amphotropic retrovirus-transduced oncogenes (pBABE-c-Myc^T58A+H-Ras^G12V). The transformed cells, WT_t and DKO_t respectively, evidenced comparable integrated copy numbers and oncogene expression. Ganglioside synthesis was completely blocked in the DKO_t cells, importantly without triggering an alternate pathway of ganglioside synthesis. Ganglioside depletion (to <0.5 nmol/10⁷ cells from 9-11 nmol/10⁷ WT_t or untransfected normal fibroblasts) did not adversely affect cell proliferation kinetics but did reduce cell migration on fibronectin-coated wells, consistent with our previous observations in ganglioside-depleted normal human fibroblasts. Strikingly, despite similar oncogene expression and growth kinetics, DKO_t cells evidenced significantly impaired tumor growth in syngeneic immunocompetent mice, underscoring the pivotal role of tumor cell gangliosides and providing an ideal system for probing their mechanisms of action in vivo.

Attitudes and Concerns of Pre-Pubescent and Pubescent Girls about Breast Health and Breast Cancer: An Unmet Need

Background: Prior research has indicated that girls have unaddressed fears about breast health and breast cancer. In a Breastcancer.org online survey (SABCS 2008 Abstract#5078), 26% of girls have already worried they may have breast cancer and 73% reported that a relative or close acquaintance had already been diagnosed. Their fears are magnified by the current trend of early onset of breast development and their sensitivity to high media coverage of breast cancer. We hypothesize that girls have limited opportunities and are without the emotional capacity and communication skills necessary to gather and process this information at home, in school, and in the doctor's office.Methods: Breastcancer.org, the Taking Care of Your “Girls” book project, and the Lankenau Hospital Health Education Center conducted an online survey of girls in middle and high schools prior to the delivery of its in-school Basic Breast Health Assembly Program in 13 Philadelphia, Atlanta, Washington, and Los Angeles area schools. 4246 girls attended an assembly, of which 3397 participated in the student survey. 1067 adult female family members (AFFM)—mostly mothers—completed the family member survey.Results: In total, 33% of girls had already learned about breast health and breast cancer in school. 48% of girls wanted to attend the Assembly Program; 93% of AFFMs wanted their girls to participate in the Assembly Program. 50% of girls said they felt uneasy starting the conversation about these topics with their AFFM, 97% of AFFMs said they felt comfortable starting the conversation with their girls, but only 43% of the girls report having the conversation. Of the girls who talked to a parent, 91% talked to their mothers and only 1% talked with their fathers. Girls and AFFMs offered many tips on how to start and sustain a healthy dialogue on these topics: listen, be open, make it fun, pick a private place and time, share experiences, provide facts, and call in experts when you need more information.42%, 18%, and 23% of girls, respectively, have talked to a doctor, sister, or friend about these topics. 50% of girls want to learn breast self-exams from their doctors.Discussion: This survey indicates that girls have unmet informational needs on breast health and breast cancer. This was a source of anxiety for both girls and their AFFMs. There was a willingness to engage in educational activities by both girls and AFFMs, but the dialogue opportunities and communication skills were seen as lacking. Girls identified AFFMs, schools, and doctors as their preferred sources of this information.Girls' ability to express their anxiety, replace fears with facts, learn breast healthy behaviors, and deal with a loved ones' diagnosis requires education, modeling, and an ongoing dialogue. This survey provides guidance for educators and healthcare professionals regarding research into interventions seeking to correct this previously underappreciated gap in public health education.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 1037.

[Intraosseous infusion. An important technique also for paediatric anaesthesia]

Timely establishment of venous access in infants and toddlers can prove a particularly challenging task. Since the 1940s the technique of intraosseous infusion has established itself as a valuable alternative means for rapid, efficient and safe delivery of drugs and fluids to critically ill children. Whereas international guidelines for paediatric emergency medical care have assigned intraosseous infusion a high priority, most anaesthetists utilize this well-proven technique with great reluctance. This article describes the technique of intraosseous infusion, introduces two different cannulation systems, and discusses its potential indications in paediatric anaesthesia, based on current emergency medical care guidelines as well as some of our own case studies. In particular, children with acutely life-threatening conditions, such as circulatory arrest, laryngospasm, acute airway haemorrhage, hypovolaemic shock or hypothermia secondary to extensive burns, should receive an intraosseous cannula if intravenous access cannot be rapidly established. Future discussion may reveal whether a transiently inserted intraosseous infusion would also be indicated if the child with difficult or impossible venous access presents without acute life-threatening conditions for anaesthesia. Successful application of the intraosseous infusion technique requires immediate access to the necessary equipment, intensive education, continuous training and clear guidelines for its application in an anaesthesia department.

Cardiac risk assessment before the use of stimulant medications in children and youth: A joint position statement by the Canadian Paediatric Society, the Canadian Cardiovascular Society, and the Canadian Academy of Child and Adolescent Psychiatry

Regulatory decisions and scientific statements regarding the management of attention-deficit hyperactivity disorder (ADHD) raise questions about the safety of medications and the appropriate pretreatment evaluation to determine suitability for treatment with medication. This is particularly true in the setting of known structural or functional heart disease. The present paper reviews the available data, including peer-reviewed literature, data from the United States Food and Drug Administration Web site on reported adverse reactions in children using stimulant medication, and Health Canada data on the same problem. A consensus-based guideline on appropriate assessment is provided, based on input from members of the Canadian Paediatric Society, the Canadian Cardiovascular Society and the Canadian Academy of Child and Adolescent Psychiatry, with specific expertise and knowledge in the areas of both ADHD and pediatric cardiology. The present statement advocates a thorough history and physical examination before starting stimulant medications, with an emphasis on the identification of risk factors for sudden death, but does not routinely recommend electrocardiographic screening or cardiac subspecialist consultation unless indicated by history or physical examination findings. A checklist for identifying children who are potentially at risk of sudden death (independent of ADHD or medications used to treat it) is provided. Although recommendations are based on the best evidence currently available, the committee further agrees that more research on this subject is necessary to optimize the approach to this common clinical scenario.

Prospective randomized controlled multi-centre trial of cuffed or uncuffed endotracheal tubes in small children

BACKGROUND

The use of cuffed tracheal tubes (TTs) in small children is still controversial. The aim of this study was to compare post-extubation morbidity and TT exchange rates when using cuffed vs uncuffed tubes in small children.

METHODS

Patients aged from birth to 5 yr requiring general anaesthesia with TT intubation were included in 24 European paediatric anaesthesia centres. Patients were prospectively randomized into a cuffed TT group (Microcuff PET) and an uncuffed TT group (Mallinckrodt, Portex, Rüsch, Sheridan). Endpoints were incidence of post-extubation stridor and the number of TT exchanges to find an appropriate-sized tube. For cuffed TTs, minimal cuff pressure required to seal the airway was noted; maximal cuff pressure was limited at 20 cm H(2)O with a pressure release valve. Data are mean (SD).

RESULTS

A total of 2246 children were studied (1119/1127 cuffed/uncuffed). The age was 1.93 (1.48) yr in the cuffed and 1.87 (1.45) yr in the uncuffed groups. Post-extubation stridor was noted in 4.4% of patients with cuffed and in 4.7% with uncuffed TTs (P=0.543). TT exchange rate was 2.1% in the cuffed and 30.8% in the uncuffed groups (P<0.0001). Minimal cuff pressure required to seal the trachea was 10.6 (4.3) cm H(2)O.

CONCLUSIONS

The use of cuffed TTs in small children provides a reliably sealed airway at cuff pressures of <or=20 cm H(2)O, reduces the need for TT exchanges, and does not increase the risk for post-extubation stridor compared with uncuffed TTs.