[Injury pattern and clinical course of children with multiple injuries in comparison to adults, Ab 11-year analysis at a clinic of maximum utilization]

Due to the small number of polytraumatized children treated in single clinics, only a few studies are available that compare multiply injured children and adults. However, the differences between the two groups with respect to type of injury, injury patterns and pathophysiology may have some crucial effect on the clinical course and are therefore essential for the treatment regime. In this study data about the epidemiology, the preclinical treatment, the clinical course and the complication rates of polytraumatized children and adults were analysed. The aim of this study was to point out the main differences between the two collectives and to compare the results with the current literature. Traffic accidents were the leading cause for trauma (children 77.8%, adults 62.6%). Children more often were transported by helicopter than adults. In both age groups head injuries and fractures of the extremities were most frequent. Adults had a prolonged ventilation time as well as an increased stay in ICU and a regular ward.

Sjögren's syndrome: the diagnostic potential of early oral manifestations preceding hyposalivation/xerostomia

Sjögren's syndrome (SS) is a systemic autoimmune exocrinopathy that affects mainly the salivary and lacrimal glands, leading to progressive reduction in saliva and tear flow. Although the underlying immuno-mediated glandular destruction is thought to develop slowly over several years, a long delay from the start of the symptoms to final diagnosis has been frequently reported. A limited knowledge concerning SS natural history is among the major causes of the actual diagnostic delay. Although very few studies have been focused on the analysis of SS early clinical onset, a series of oral features preceding xerostomia/hyposalivation development in patients eventually diagnosed as having SS have been reported. Sialochemistry alterations, salivary gland swelling, early dental loss and sialorrhea have been observed before the onset of typical signs and symptoms (namely xerostomia and/or hyposalivation), which usually lead to SS clinical presentation and diagnosis. Here we suggest, after evaluating available data, that the traditional 'untouchable' association between SS and xerostomia/hyposalivation might probably be reconsidered, and that astute clinicians should not underestimate the possible presence or development of SS in patients without xerostomia/hyposalivation and presenting these atypical early oral features.

[Evaluation of unstimulated and stimulated parotid salivary flow rate in Israeli healthy subjects aged 60 years and older]

Saliva plays a critical role in the maintenance oral health. Clinical studies showed that 25% of the elderly population suffers from oral dryness and its related complaints. Studies that measured parotid gland salivary flow rate, both unstimulated and stimulated, in healthy older individuals did not find age-related functional changes. However, histological studies have revealed an age-dependent reduction in the parotid acinar tissue component. To our knowledge there are still no reports of the parotid salivary flow rate in the elderly population in Israel. The goal of this study was to evaluate the rate of the parotid unstimulated and stimulated salivary flow rate among healthy Israeli people aged over 60 years old--the findings may serve as basic standard values to be compared to data collected from patients with complaints of xerostomia and to data reported in other studies. Thirty healthy volunteers aged 60 to 77 years (average 64.7), 23 females and 7 males, were evaluated. Twenty five of the subjects used to live in kibbutzim and 5 lived in a city. The mean unstimulated parotid salivary secretion rate was 0.044+/-0.063 ml/min and the mean stimulated secretion was 0.163+/-0.291 ml/min. Those rates were found to be lower than the unstimulated and stimulated parotid salivary flow rates reported in most other studies. Fourteen (43.3) of the subjects had zero flow rate at rest. This figure was higher then the 20% zero flow at rest that was reported by others among persons with a broader age range. No significant differences were recorded in the parotid salivary flow, both unstimulated and stimulated, between subjects living in the kibbutzim compared to those living in the city. Similar to other studies the differences in the secretion rates between men and women were non significant. The low mean unstimulated and stimulated salivary flow rates, and the high prevalence of no flow at rest can be explained by the fact that saliva collections were done during the very warm Israeli summer and it is speculated that the subjects might be dehydrated. General dehydration can be observed in warm climate areas. No significant differences were found in the parotid salivary flow rates, (unstimulated and stimulated), between the city subjects compared to those from the kibbutzim. Further similar studies in different weather conditions (winter-summer) are needed to establish data of the normal parotid salivary secretion in the over 60 years old Israeli population.

Micro patterning of cell and protein non-adhesive plasma polymerized coatings for biochip applications

Micro scale patterning of bioactive surfaces is desirable for numerous biochip applications. Polyethyleneoxide-like (PEO-like) coating with non-fouling functionality has been deposited using low frequency AC plasma polymerization. The non-fouling properties of the coating were tested with human cells (HeLa) and fluorescence labeled proteins (isothiocyanate-labeled bovine serum albumin, i.e. FITC-BSA). The PEO-like coatings were fabricated by plasma polymerization of 12-crown-4 (ppCrown) with plasma polymerized hexene (ppHexene) as adhesion layer. The coatings were micro patterned using conventional cleanroom photolithography and lift-off. Single cell arrays showed sharp contrast in cell adhesion between the untreated glass surface and the ppCrown layer. Similarly, proteins adsorbed selectively to untreated glass but not to ppCrown. The simplicity of the lift-off technique and the sturdiness and versatility of the plasma-polymerized coatings, make this technology highly suitable for bio-MEMS and biochip applications, where patterned high contrast non-fouling surfaces are needed.

Measurements of scattered light on a microchip flow cytometer with integrated polymer based optical elements

Flow cytometry is widely used for analyzing microparticles, such as cells and bacteria. In this paper, we report an innovative microsystem, in which several different optical elements (waveguides, lens and fiber-to-waveguide couplers) are integrated with microfluidic channels to form a complete microchip flow cytometer. All the optical elements, the microfluidic system, and the fiber-to-waveguide couplers were defined in one layer of polymer (SU-8, negative photoresist) by standard photolithography. With only a single mask procedure required, all the fabrication and packaging processes can be finished in one day. Polystyrene beads were measured in the microchip flow cytometer, and three signals (forward scattering, large angle scattering and extinction) were measured simultaneously for each bead. To our knowledge this is the first time forward scattered light and incident light extinction were measured in a microsystem using integrated optics. The microsystem can be applied for analyzing different kinds of particles and cells, and can easily be integrated with other microfluidic components.

The flow rate of whole and submandibular/sublingual gland saliva in patients receiving replacement complete dentures

Provision of complete dentures to a new denture wearer increases the salivary flow rate is well known. The new dentures act as an additional mechanical stimulus to the salivary reflexes, thus increasing the flow rate. The purpose of this study was to determine whether replacing complete dentures would elicit the same response. Unstimulated and stimulated whole and submandibular/sublingual (SM/SL) saliva were collected before inserting complete replacement dentures and again after 2 days and after 3 weeks of denture wearing. Unstimulated whole salivary flow rate increased significantly 2 days after inserting replacement dentures, decreasing at 3 weeks but remaining significantly above the baseline. Stimulated whole salivary flow rate increased significantly after 2 days but decreased to normal after 3 weeks. Stimulated and unstimulated SM/SL salivary flow rate increased significantly after 2 days, decreasing at 3 weeks while remaining significantly above the values found before denture insertion.

Individualized medicine - implementation of pharmacogenetic diagnostics in antidepressant drug treatment of major depressive disorders

Antidepressant drug therapy is characterized by a high rate of therapeutic failure. There is increasing evidence that genetic factors are contributing to the inter-individual variability in antidepressant drug response. Genetic variability is described in both the pharmacokinetic part of drug action as well as in pharmacodynamic structures mediating drug effects. Genetic polymorphisms in drug metabolizing enzymes are well characterized and have large effects on oral clearances or elimination half-lives of antidepressant drugs. These differences can be compensated by adapting the individual dose to genotype in addition to other factors such as gender, weight, age, liver and kidney function. On the part of drug action, genetic variability is described in molecular structures of antidepressant effects. Several studies on response of antidepressants have revealed influences of polymorphisms in neurotransmitter receptors and transporters changing sensitivity of patients to treatment with antidepressants; however, results were often contradictory. A pharmacogenomic approach to individualize antidepressant drug treatment is recommended to be based on several levels: 1) identifying and validating the candidate genes involved in drug-response; 2) providing therapeutic guidelines; and 3) developing a pharmacogenetic test-system for bedside-genotyping.

Removal of PCR inhibitors using dielectrophoresis as a selective filter in a microsystem

Diagnostic PCR has been used to analyse a wide range of biological materials. Conventional PCR consists of several steps such as sample preparation, template purification, and PCR amplification. PCR is often inhibited by contamination of DNA templates. To increase the sensitivity of the PCR, the removal of PCR inhibitors in sample preparation steps is essential and several methods have been published. The methods are either chemical or based on filtering. Conventional ways of filtering include mechanical filters or washing e.g. by centrifugation. Another way of filtering is the use of electric fields. It has been shown that a cell will experience a force when an inhomogeneous electric field is applied. The effect is called dielectrophoresis (DEP). The resulting force depends on the difference between the internal properties of the cell and the surrounding fluid. DEP has been applied to manipulate cells in many microstructures. In this study, we used DEP as a selective filter for holding cells in a microsystem while the PCR inhibitors were flushed out of the system. Haemoglobin and heparin - natural components of blood - were selected as PCR inhibitors, since the inhibitory effects of these components to PCR have been well documented. The usefulness of DEP in a microsystem to withhold baker's yeast (Saccharomyces cerevisiae) cells while the PCR inhibitors haemoglobin and heparin are removed will be presented and factors that influence the effect of DEP in the microsystem will be discussed. This is the first time dielectrophoresis has been used as a selective filter for removing PCR inhibitors in a microsystem.

Integrating advanced functionality in a microfabricated high-throughput fluorescent-activated cell sorter

The integration of complete analyses systems "on chip" is one of the great potentials of microfabricated devices. In this study we present a new pressure-driven microfabricated fluorescent-activated cell sorter chip with advanced functional integration. Using this sorter, fluorescent latex beads are sorted from chicken red blood cells, achieving substantial enrichments at a sample throughput of 12000 cells s(-1). As a part of the sorter chip, we have developed a monolithically integrated single step coaxial flow compound for hydrodynamic focusing of samples in flow cytometry and cell sorting. The structure is simple, and can easily be microfabricated and integrated with other microfluidic components. We have designed an integrated chamber on the chip for holding and culturing of the sorted cells. By integrating this chamber, the risk of losing cells during cell handling processes is eliminated. Furthermore, we have also developed integrated optics for cell detection. Our new design contributes to the ongoing efforts for building a fully integrated micro cell sorting and analysing system.

Presenting XML-based medical discharge letters according to CDA

The HL7 Clinical Document Architecture (CDA) is an important XML-based standard for the representation of clinical documents.

OBJECTIVES

The use of Markup Languages could satisfy the demands of involved healthcare staff as well as the needs of patients, to receive an overview of the patient's treatment during the hospital stay. The standardization efforts of different groups dealing with this problem have demonstrated progress, but have not, as yet, achieved a routinely usable result. In particular, differentiating information according to a hierarchical order has not been published to date.

METHODS

A retrospective analysis of 60 discharge letters from a cardiology ward (ward A) as well as 60 discharge letters from a gastroenterology ward (ward B) were extracted from the central hospital information system, by taking every fifth discharge letter issued over a one year period.

RESULTS

An XML-based prototype for medical discharge letters has been put in place representing the required information units and information elements. By means of an XSL-stylesheet, a detailed representation of the conventional discharge letter has been produced that is platform independent and permits the recurrent use of information units.

CONCLUSIONS

Through the introduction of definitions like information elements and information units, progress in the development of CDA level two and three might be realized. We present a method by which discharge letters can be used by an Internal Medicine Department. This concept is implemented in a XML-based prototype allowing a special view on XML data to generate this document type.

Diagnosis of a cardiac angiosarcoma by fluorine-18 fluordeoxyglucose positron emission tomography

Cardiac angiosarcoma is a rare tumour entity with a poor prognosis. Early detection is difficult but important for the further course of the disease. We report on a young patient with a tumour of unknown origin and dignity of the right atrium. Magnetic resonance imaging, CT and echocardiography were sufficient in localisation, but no statement on the dignity was possible. Furthermore, staging led to ambiguous results. Malignancy could be proved by fluorine-18 fluordeoxyglucose positron emission tomography, leading to early surgery. Histology revealed a poorly differentiated angiosarcoma.

Can salivary composition and high flow rate explain the low caries rate in children with familial dysautonomia?

PURPOSE

Extremely low caries rate and increased major salivary gland flow rare have been previously reported in children with familial dysautonomia (FD). The purpose of this study was to explore the possibility that, in addition to increased salivary flow, children with FD have alterations in their salivary components, which may suggest an explanauon to their low caries rate.

METHODS

Whole unstimulated and stimulated saliva samples were collected from 13 children with FD who were found to be caries free, and from 28 age- and ethnic-matched healthy children, 15 caries-free children and 13 caries-affected children. The electrolyte and protein content of the unstimulated saliva and the microbial count and buffering capacity of the stimulated saliva were determined.

RESULTS

Children with FD had the highest salivary flow rate and the lowest levels of mutans streptococci and lactobacilli, as well as the lowest concentration of chloride, magnesium, total protein and IgA. Healthy caries-affected children displayed the highest mutans streptococci and lactobacilli levels and lysozyme concentration, concomitantly with the lowest potassium and calcium concentrations.

CONCLUSIONS

The results of this investigation suggest that the caries-free state in FD may be associated with high salivary flow rate, while in healthy children, low caries rate may be associated with high salivary calcium concentration.

AIDA: Web agents to support dental treatment planning

Dental treatment planning is highly dependent on the educational background and personal experience of the dentist and on the thoroughness with which findings are taken. The objective of research in the AIDA (Artificially Intelligent Dental Agents) project is therefore the analysis of dental decision making and the design of a decision-supportive software module to test the decision-making process and make it transparent for both dentists and patients. In the AIDA project (aida.uni-hd.de), an expert system has been set up to identify treatment alternatives with integrated decision rationale for experts, practicing dentists, and eventually also patients. It is based on a top-down structure for dental decision-making, which was developed to standardize argumentation. For prosthetic dentistry, how one uses individual patient findings to arrive at possible treatment alternatives was clarified in greater detail. The planning rules for fixed prostheses have already been integrated into a software agent. Other modules should soon specify and verify these suggestions in terms of further fields of dentistry (e.g., restorative dentistry). In the near future, AIDA will be able to deliver dentally-founded justifications for every individual decision.

Five Nkx5 genes show differential expression patterns in anlagen of sensory organs in medaka: insight into the evolution of the gene family

We report the identification and characterisation of five different Nkx5-related genes in medaka fish (Oryzias latipes). They constitute homologues of genes previously isolated in higher vertebrates, Nkx5--1, Nkx5--2, Hmx1/Nkx5--3 and SOHo-1, and were named accordingly: OlNkx5--1.1, OlNkx5--2, OlNkx5--3 and OlSOHo. For the Nkx5--1 gene a new, second homologue, OlNkx5--1.2, was isolated. In medaka, Nkx5 and SOHo genes are differentially expressed in three developing sensory organs: eye, ear and lateral line and later in defined brain regions. Phylogenetic analyses of the entire Nkx5 family revealed that four paralogous Nkx5 groups, Nkx5--1, Nkx5--2, Hmx1/Nkx5--3/GH6 and SOHo, are present in vertebrates. Only some of the Nkx5 family members have been identified in singular vertebrate species so far. Here we present, for the first time, the isolation of representatives of each Nkx5 subgroup in one species, the medaka fish. Based on similarities in sequence and expression patterns, and genomic organisation we propose a model of the evolutionary history of the Nkx5 family. The model predicts that the four vertebrate Nkx5 genes arose by a tandem duplication, followed by chromosomal duplication. The two Nkx5--1 genes identified so far exclusively in medaka most probably result from an additional genome duplication in the fish lineage.

Evidence that wild-type p53 in neuroblastoma cells is in a conformation refractory to integration into the transcriptional complex

Neuroblastoma (NB) cells reportedly accumulate wild-type p53 exclusively in the cytoplasm. However, immunofluorescence assays with five different antibodies showed that p53 accumulates in the nucleus of up to 10% of NB cells. PAb1801 detected cytoplasmic 'punctate structures' which were also found in p53-null cells, rendering this antibody unsuitable for p53 detection. A comparison of DO-1 and PAb1801 staining in NB tissue sections confirmed the results obtained with NB cells. Nuclear accumulation of p53 was induced in NB cells using substances which disturb p53's tertiary structure at its zinc finger motif, or by treatment with mitomycin C. Constitutive nuclear accumulation was observed in an SK-N-SH variant, AW-1, which has a point mutation in p53 at Cys176>Ser, disturbing the same motif. Even though p53 showed DNA-binding capability after mitomycin C treatment of NB cells, the target gene products MDM2 and p21(WAF1,CIP1,SDI1) were not synthesized and no p53 transactivating activity measured in a reporter gene assay. Therefore we suggest that p53 in NB cells might be predominantly in a conformation refractory to integration into the transcriptional complex, resulting in at least partial transcriptional inactivity, hyperactive nuclear export and resistance to degradation by exogenously expressed MDM2.

p53 in SV40-transformed DNA-damaged human cells binds to its cognate sequence but fails to transactivate target genes

Human SV40-transformed cells contain high levels of stabilized p53 of which only a fraction is complexed with the SV40 large tumor antigen (T-antigen). This raises the question whether the p53 which is not complexed with T-antigen retains some biological activity. Two human SV40-transformed cell lines, BEAS and SV80, were investigated. A significant level of constitutive cognate-sequence-specific DNA-binding of p53 was detected by electrophoretic mobility shift assay (EMSA) of cell extracts. Upon DNA damage by treatment with mitomycin C the DNA-binding activity was increased, as known for cells with wild-type p53. However, in both cell lines, before and after DNA damage, p53 was not able to transactivate a target gene as shown by reporter gene assay. Hence, the capability of p53 to bind its cognate sequence is a prerequisite but no proof of p53 transactivating activity. Nuclear p53 levels were not further increased after mitomycin C treatment, occasionally rather slightly decreased, often accompanied by an even larger decrease in amount of T-antigen. In conclusion, SV40-transformation of human cells has caused a loss of essential features of wild-type p53 activity, even in that fraction of p53 not in physical complex with SV40 T-antigen.

NCCN Practice Guidelines for Breast Cancer

The therapeutic options for patients with noninvasive or invasive breast cancer are complex and varied. In many situations, the patient and physician have the responsibility to jointly explore and ultimately select the most appropriate option from among the available alternatives. With rare exception, the evaluation, treatment, and follow-up recommendations contained within these guidelines were based largely on the results of past and present clinical trials. However, there is not a single clinical situation in which the treatment of breast cancer has been optimized with respect to either maximizing cure or minimizing toxicity and disfigurement. Therefore, patient and physician participation in prospective clinical trials allows patients not only to receive state-of-the-art cancer treatment but also to contribute to the improvement of treatment of future patients.

Mouse peripherin isoforms

Three distinct mRNAs have been shown to be produced by alternative splicing from the unique mouse peripherin gene. They generate three translation products, one major form, Pe-58, and two minor forms, Pe-56 which possess a shorter C-terminal sequence, and Pe-61 in which an additional sequence has been inserted in the central rod domain (Landon et al., 1989, EMBO J. 8, 1719-1726). In this study, the simultaneous occurrence of multiple transcripts in murine nervous tissues and neuroblastoma cell lines was shown by PCR amplification of fragments overlapping the sites of alternative splicing. Recombinant peripherin isoforms were purified from E. coli expressing full-length cDNAs. Rabbit antisera were raised against synthetic peptides mimicking parts of the two C-terminal sequences and of the inserted sequence of Pe-61 and were immunoadsorbed until they became monoreactive. By western blot analysis, the peripherin isoforms were localised in neuroblastoma NB2a cell lysates and detergent insoluble fractions separated by two-dimensional electrophoresis. In addition, each isoform was resolved into several charge variants. At the cellular level, each antibody decorated the filament array of the NB2a cells, suggesting the participation of the minor peripherin isoforms in the intermediate filament network.

Effects of BG9719 (CVT-124), an A1-adenosine receptor antagonist, and furosemide on glomerular filtration rate and natriuresis in patients with congestive heart failure

OBJECTIVES

To determine the effects of furosemide and the selective A1 adenosine receptor BG9719 on renal function in patients with congestive heart failure (CHF).

BACKGROUND

Studies suggest that adenosine may affect renal function by various mechanisms, but the effects of blockade of this system in humans is unknown. In addition, the effects of a therapeutic dose of furosemide on glomerular filtration rate (GFR) and renal plasma flow (RPF) in heart failure patients are controversial.

METHODS

On different days, 12 patients received placebo, BG9719 and furosemide. Glomerular filtration rate, RPF and sodium and water excretion were assessed immediately following drug administration.

RESULTS

Glomerular filtration rate was 84 +/- 23 ml/min/1.73m2 after receiving placebo, 82 +/- 24 following BG9719 administration and a decreased (p < 0.005) 63 +/- 18 following furosemide. Renal plasma flow was unchanged at 293 +/- 124 ml/min/1.73m2 on placebo, 334 +/- 155 after receiving BG9719 and 374 +/- 231 after receiving furosemide. Sodium excretion increased from 8 +/- 8 mEq following placebo administration to 37 +/- 26 mEq following BG9719 administration. In the six patients in whom it was measured, sodium excretion was 104 +/- 78 mEq following furosemide administration.

CONCLUSIONS

Natriuresis is effectively induced by both furosemide and the adenosine A1 antagonist BG9719 in patients with CHF. Doses of the two drugs used in this study did not cause equivalent sodium and water excretion but only furosemide decreased GFR. These data suggest that adenosine is an important determinant of renal function in patients with heart failure.

[Computer-assisted documentation and therapy planning in pediatric oncology--introduction of a nationwide solution]

In Pediatric Oncology in Germany, 90% of the patients are treated according to multicenter clinical trials, which means an enormous effort for documentation in the participating clinics. In order to enable multiple use of data for patient records as well as for clinical trials a computer-based documentation system for pediatric oncology (DOSPO) is being developed, which can be used nationwide. DOSPO currently comprises a minimum basic data set, which represents the common core of all multicenter trials and which has been approved by the German Society for Pediatric Oncology and Hematology (GPOH). It is intended to enhance the documentation by specific items of each clinical trial. Functions for computer-aided chemotherapy planning and medical report writing have already been implemented in the documentation system. Various centers in Germany are currently validating the system in routine use.

Iron supplemented formula milk related to reduction in psychomotor decline in infants from inner city areas: randomised study

OBJECTIVE

To compare the effect of unmodified cows' milk and iron supplemented formula milk on psychomotor development in infants from inner city areas when used as the main milk source.

DESIGN

Double blind, randomised intervention trial.

SETTING

Birmingham health centre.

SUBJECTS

100 infants, mean age 7.8 months (range 5.7 to 8.6 months), whose mothers had already elected to use unmodified cows' milk as their infant's milk source.

INTERVENTION

Changing to an iron supplemented formula milk from enrolment to 18 months of age, or continuing with unmodified cows' milk.

MAIN OUTCOME MEASURES

Developmental assessments using Griffiths scales at enrolment and at 18 and 24 months.

RESULTS

85 participants completed the trial. There were no significant differences in haemoglobin concentration between the two groups at enrolment, but by 18 months of age 33% of the unmodified cows' milk group, but only 2% of the iron supplemented group, were anaemic (P<0.001). The experimental groups had Griffiths general quotient scores that were not significantly different at enrolment, but the scores in both groups declined during the study. By 24 months the decrease in the mean scores in the unmodified cows' milk group was 14.7 whereas the decrease in the mean scores in the iron supplemented group was 9.3 (P<0.02, 95% confidence interval 0.4 to 10.4). Mean subquotient scores were considerably lower in the unmodified cows' milk group at 24 months; significantly so for personal and social scores (P<0.02, 1.2 to 16.8 [corrected]).

CONCLUSION

Replacing unmodified cows' milk with an iron supplemented formula milk up to 18 months of age in infants from inner city areas prevents iron deficiency anaemia and reduces the decline in psychomotor development seen in such infants from the second half of the first year.

Understanding the influence of temperature change and cosolvent addition on conversion rate of enzymatic suspension reactions based on regime analysis

It is a commonly held belief that enzymatic conversions of substrate in aqueous suspensions can be speeded up by raising the temperature or adding organic solvents to promote dissolution of the substrate. To quantify the impact of such changes, we studied the alpha-chymotrypsin-catalyzed hydrolysis of dimethyl benzylmethylmalonate as a model system. It was found that, upon addition of organic cosolvents, longer process times were actually required, even though the substrate solubility increased severalfold as expected. Upon raising the temperature from 25 degrees C to 37 degrees C, on the other hand, both the substrate solubility, the substrate dissolution rate, and the enzymatic reaction rate increased, leading to shorter process times. A dissolution-reaction model incorporating the kinetics of enzyme deactivation could be developed. A simple relation for the prediction of the overall process time was established by evaluating the time constants for the subprocesses: substrate dissolution; enzymatic conversion; and enzyme deactivation. Using regime analysis, rules of thumb for the optimization of an enzymatic suspension reaction were derived.

A comparison of an A1 adenosine receptor agonist (CVT-510) with diltiazem for slowing of AV nodal conduction in guinea-pig

1. The purpose of this study was to compare the pharmacological properties (i.e. the AV nodal depressant, vasodilator, and inotropic effects) of two AV nodal blocking agents belonging to different drug classes; a novel A1 adenosine receptor (A1 receptor) agonist, N-(3(R)-tetrahydrofuranyl)-6-aminopurine riboside (CVT-510), and the prototypical calcium channel blocker diltiazem. 2. In the atrial-paced isolated heart, CVT-510 was approximately 5 fold more potent to prolong the stimulus-to-His bundle (S-H interval), a measure of slowing AV nodal conduction (EC50 = 41 nM) than to increase coronary conductance (EC50 = 200 nM). At concentrations of CVT-510 (40 nM) and diltiazem (1 microM) that caused equal prolongation of S-H interval (approximately 10 ms), diltiazem, but not CVT-510, significantly reduced left ventricular developed pressure (LVP) and markedly increased coronary conductance. CVT-510 shortened atrial (EC50 = 73 nM) but not the ventricular monophasic action potentials (MAP). 3. In atrial-paced anaesthetized guinea-pigs, intravenous infusions of CVT-510 and diltiazem caused nearly equal prolongations of P-R interval. However, diltiazem, but not CVT-510, significantly reduced mean arterial blood pressure. 4. Both CVT-510 and diltiazem prolonged S-H interval, i.e., slowed AV nodal conduction. However, the A1 receptor-selective agonist CVT-510 did so without causing the negative inotropic, vasodilator, and hypotensive effects associated with diltiazem. Because CVT-510 did not affect the ventricular action potential, it is unlikely that this agonist will have a proarrythmic action in ventricular myocardium.

A novel system of human submandibular/sublingual saliva collection

The assessment of submandibular/sublingual (sm/sl) saliva is a procedure of increasing significance. However, the collection of these fluids by traditional techniques is difficult and therefore often neglected. To collect sm/sl saliva, we have assembled a novel, universal system consisting of four parts-collecting tubing, a buffering chamber, a storing tube, and a suction device. Submandibular/sublingual saliva samples were collected from ten healthy and ten xerostomic individuals. The system showed intra-examiner reproducibility of 0.92 for healthy and 0.89 for xerostomic subjects, and inter-examiner reproducibility of 0.93 for normal subjects and 0.80 for xerostomic individuals. The flow rates obtained by the present collecting set-up were similar to those measured by all known previous methods that were published during the last 40 years. The system was also efficient, in that more than 90% of the fluid that entered the system was eventually collected in the storing tube for analysis. The system appears to collect relatively pure sm/sl fluids, since contamination of the collected sample by a stimulant solution swabbed repeatedly over the tongue during saliva collection was minimal. The system is reliable, safe, practical, and comfortable for the patient.

Cortical and medullary somatosensory projections to the cochlear nuclear complex in the hedgehog tenrec

Various tracer substances were injected into the spinal cord, the dorsal column nuclei, the trigeminal nuclear complex and the somatosensory cortex in Madagascan hedgehog tenrecs. With the exception of the cases injected exclusively into the spinal cord all injections gave rise to sparse, but distinct anterograde projections to the cochlear nuclear complex, particularly the granular cell domain within and outside of the dorsal cochlear nucleus. Among these cochlear afferents the projection from the primary somatosensory cortex is the most remarkable because the hedgehog tenrec has one of the lowest encephalisation indices among mammals and a similar cortico-cochlear connection has not been demonstrated so far in other species.

The combination of two semen preparation techniques (glass wool filtration and swim-up) and their effect on the morphology of recovered spermatozoa and outcome of IVF-ET

The aim of this prospective study was to relate sperm quality, especially sperm morphology, to the outcome of IVF results, when glass wool filtration (GWF) and swim-up were used in combination for the preparation of spermatozoa. A total of 60 ejaculates were analysed. GWF was compared with glass wool filtration/swim-up (GWF-SU) by using aliquots from the same semen samples to increase the precision of the comparison and to establish the cumulative effect of these two semen preparation methods on the morphology of the recovered spermatozoa. Sperm parameters were examined in native semen, in semen preparation samples after GWF and GWF-SU. The mean percentages for motility, morphology and velocity were improved significantly over those in fresh semen only when GWF-SU was used. GWF alone resulted only in a significantly higher recovery of motile spermatozoa. In semen preparation, 10% of spermatozoa with normal morphology appeared to be the cut-off point as there was a significantly higher recovery in fresh semen samples containing > 10% morphologically normal spermatozoa after GWF-SU. Outcome of IVF-ET following preparation with GWF-SU showed better results in comparison to the swim-up procedure alone, though this difference was not statistically significant. The cut-off point was also > 10% morphologically normal spermatozoa. Improvement in all aspects of IVF-ET occurred when native semen contained > 10% morphologically normal spermatozoa. It is concluded that GWF alone did not produce significantly better results but, in combination with swim-up, it resulted in significantly better sperm morphology and in an improved outcome of IVF-ET for fresh semen samples with > 10% morphologically normal spermatozoa.

Increased major salivary gland secretion in familial dysautonomia

Familial dysautonomia (FD), an autosomal recessive peripheral nervous system disorder, affects almost exclusively children of Jewish Ashkenazi origin and causes profound generalized autonomic dysfunction. Excessive drooling is frequent and is traditionally attributed to swallowing difficulties. Although true hypersalivation has been postulated, no quantitative assessment of the salivary secretion rate has yet been reported. The authors determined this rate in 13 children with FD and 28 healthy controls. Resting parotid, submandibular/sublingual and unstimulated whole salivary secretion rates were significantly elevated in children with FD. The known relation of salivary function with age was found in controls only. This apparently major contribution of salivary hyperfunction to excessive drooling in FD may be attributable to salivary gland denervation supersensitivity, as this mechanism is present in the cardiovascular system and the pupil in FD.

Synaptic and non-synaptic cholinergic innervation of the various types of neurons in the main olfactory bulb of adult rat: immunocytochemistry of choline acetyltransferase

The cholinergic neuronal structures and their synaptic connections in the main olfactory bulb of adult rats were analysed by using choline acetyltransferase immunocytochemistry. Within the glomeruli, cholinergic nerve fibers were restricted to strands which subdivided the neuropil into small compartments, the interior of which contained sensory axons but was devoid of cholinergic axons. Small numbers of choline acetyltransferase neurons were detected in all layers. Ultrastructural analysis revealed selective triadic synaptic relationships with different neuron classes in the intraglomerular area and in the external plexiform layer. These triads were made up of (i) a cholinergic axon, (ii) one or several periglomerular or granule cell dendrites, and (iii) usually one relay cell dendrite. In these triads, asymmetric cholinergic synapses were selectively focused on dendrites (gemmules and spines) of periglomerular or granule cells. Within the glomerulus, mitral and tufted cell dendrites were closely apposed to some cholinergic axon varicosities, most abundantly near arborizations of the apical dendrites. However, cholinergic synapses were never seen on any relay cell dendrite. In the external plexiform layer, cholinergic synapses were present on all parts of the superficial short-axon cells. In the internal plexiform layer and the granule cell layer, cholinergic axon varicosities exhibited close apposition or asymmetric synapses with granule cell gemmules. The data suggest that cholinergic projections from the basal forebrain to the main olfactory bulb focus synaptic innervation on interneurons. On relay cells, direct acetylcholine effects may occur, but these must be based on non-synaptic acetylcholine release at the surface of their dendrites.

A novel antibiofilm technology for contact lens solutions

PURPOSE

Nonsteroidal anti-inflammatory drugs, including sodium salicylate, inhibit extracellular bacterial biofilm production. The authors studied the effect of the addition of sodium salicylate on bacterial adherence and biofilm formation on contact lenses and cases and commonly used medical polymers.

METHODS

The study was done in vitro with bacterial adherence and biofilm measured on lenses and cases that were exposed to saline contaminated with Staphylococcus epidermidis and Pseudomonas aeruginosa with and without 1 and 3 mm sodium salicylate. Bacterial adherence to contact lenses was quantitated by a vortex assay and by scanning electron microscopy. Biofilm formation on contact lens cases and other polymers was measured by an optical density assay and a radiolabeling assay.

RESULTS

Inhibition of biofilm formation was demonstrated on plastic contact lens cases in a dose-related manner with 1 and 3 mm sodium salicylate. A dose-related decrease in bacterial adherence also was noted. Assays with contact lenses also demonstrated less adherence in the presence of sodium salicylate. Electron micrographs of the contact lens showed less biofilm, most noticeable with 3 mm salicylate. Other studies demonstrated decreased adherence of S. epidermidis to polyethylene and polystyrene. Sodium salicylate also decreased biofilm on plastic tissue culture wells, but sorbic acid paradoxically increased deposition.

CONCLUSION

The authors found that the addition of low-dose sodium salicylate to saline decreased the adherence of S. epidermidis and P. aeruginosa to contact lenses and lens cases. Biofilm production also was decreased on the lens cases and on medical polymers used to make plastic cases. These studies suggest that sodium salicylate deserves additional study to determine its use in contact lens solutions.

Differential distribution of glutamylated tubulin during spermatogenesis in mammalian testis

The distribution of glutamylated tubulin has been analyzed in mammalian testis using the specific mAb GT335 by immunoelectron microscopy and immunoblotting. In spermatozoa of various species, immunogold labeling showed the presence of glutamylated tubulin in all of the microtubules of axoneme and centrioles, whereas the microtubule network of the spermatid manchette was unlabeled. In earlier germ cells, centriole was the only microtubule structure to be labeled. A similar distribution was observed using the anti-acetylated tubulin antibody (6-11B-1), confirming previous results of Hermo et al. [Anat. Rec. 229:31-50, 1991]. However, among testicular somatic cells, microtubules of some Sertoli cell branches were not acetylated but glutamylated. 2-D PAGE of mouse and hamster sperm extracts showed a high level of alpha and beta-tubulin heterogeneity, comparable to that found in brain. Immunoblotting with GT335 revealed a large amount of glutamylated tubulin resolved into numerous alpha as well as beta-tubulin isoforms. This suggests that the major testis-specific tubulin isotypes (m alpha 3/7 and m beta 3) are also glutamylatable. These results show a subcellular sorting of posttranslationally modified tubulin isoforms in spermatids, glutamylation being associated with the most stable microtubule structures.

Glutamylated tubulin probed in ciliates with the monoclonal antibody GT335

Microtubular networks are extensively developed in many ciliate species. In several of them, we investigate the occurrence of the post-translational glutamylation of tubulin [Eddé et al., 1990: Science 247:82-85; Eddé et al., 1991: J. Cell. Biochem. 46:134-142] using as a probe for such modified tubulin, the monoclonal antibody GT335 [Wolff et al., 1992: Eur. J. Cell Biol. 59:425-432]. Results obtained in Paramecium strongly suggest that both axonemal and cytoplasmic tubulin are glutamylated. As in the vertebrate brain tubulin so far tested, the GT335 epitope is located at the carboxy-terminal fragment of cytoplasmic tubulin removed by subtilisin treatment. Immunoblotting and immunofluorescence experiments reveal that, unlike tubulin acetylation, glutamylation is not restricted to cold-resistant microtubules. In addition, immunofluorescence studies performed on dividing cells show that glutamylation takes place soon after the polymerization of microtubules. Finally, glutamylated tubulin is also detected in the ciliate species Euplotes, Tetrahymena, and Paraurostyla. Together with results obtained on flagellate species, this suggests that tubulin glutamylation came out early in the course of eukaryotic evolution and has been widely exploited in various cellular strategies.

Structure of the polyglutamyl chain of tubulin: occurrence of alpha and gamma linkages between glutamyl units revealed by monoreactive polyclonal antibodies

Polyglutamylation, a posttranslational modification which consists of the sequential addition of one to six glutamyl units in the carboxy-terminal domain of both tubulin subunits, is a major event in neurons. Its structure has been investigated by using monoreactive polyclonal antibodies directed against distinct glutamylation motifs, ie alpha- and gamma-linkages between glutamyl units. It is shown that, beside alpha-linkages previously characterized, gamma-linkages also occur in glutamyl chains of brain tubulin. The co-existence of these two basic motifs leads to a conception of the polyglutamyl chain with a very sophisticated structure which could, through its complexity, help the microtubule to reach its structure and fulfil its functions.