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M Beck

Publications and source records attributed to M Beck.

At least 163 records · Page 9Linked to original sources
PubMed1998

[The genomic characterization of the Cuban strain with a light cytopathic effect].

The genomic characterization of the strain of light cytopathic effect by nucleotide sequence is presented. It was possible to sequence 90% of the strain of light cytopathic effect. A close relationship with Coxsackie A9 was observed. The greatest mutations occurred in the region of the genome that codifies for the structural proteins. Therefore, it may be considered as a variant of Coxsackie A9 never reported before.

Animals↗
PubMed1998

Anesthetic efficacy of a repeated intraosseous injection given 30 min following an inferior alveolar nerve block/intraosseous injection.

To determine whether a repeated intraosseous (IO) injection would increase or prolong pulpal anesthesia, we measured the degree of anesthesia obtained by a repeated IO injection given 30 min following a combination inferior alveolar nerve block/intraosseous injection (IAN/IO) in mandibular second premolars and in first and second molars. Using a repeated-measures design, we randomly assigned 38 subjects to receive two combinations of injections at two separate appointments. The combinations were an IAN/IO injection followed approximately 30 min later by another IO injection of 0.9 ml of 2% lidocaine with 1:100,000 epinephrine and a combination IAN/IO injection followed approximately 30 min later by a mock IO injection. The second premolar, first molar, and second molar were blindly tested with an Analytic Technology pulp tester at 2-min cycles for 120 min postinjection. Anesthesia was considered successful when two consecutive readings of 80 were obtained. One hundred percent of the subjects had lip numbness with IAN/IO and with IAN/IO plus repeated IO techniques. Rates of anesthetic success for the IAN/IO and for the IAN/IO plus repeated IO injection, respectively, were 100% and 97% for the second premolar, 95% and 95% for the first molar, and 87% and 87% for the second molar. The repeated IO injection increased pulpal anesthesia for approximately 14 min in the second premolar and for 6 min in the first molar, but no statistically significant differences (P > 0.05) were shown. In conclusion, the repeated IO injection of 0.9 ml of 2% lidocaine with 1:100,000 epinephrine given 30 min following a combination IAN/IO injection did not significantly increase pulpal anesthesia in mandibular second premolars or in first and second molars.

Adolescent↗
PubMed1997

Amyloid precursor protein in guinea pigs--complete cDNA sequence and alternative splicing.

We present the cDNA sequence of the guinea pig amyloid precursor protein comprising the complete coding sequence of 770 amino-acid residues. By alternative splicing of three exons transcripts encoding for 695, 714 and 751 amino acids and all forms previously denoted as L-APP are also generated. Guinea pig amyloid precursor protein was shown to exhibit extensive sequence similarity to its human and murine homologues of approx. 97% at the protein level which implies an evolutionary conserved but yet not fully understood physiological function.

Alternative Splicing↗
PubMed1997

[Enzyme replacement therapy: a new treatment concept in Gaucher disease].

Until recently the treatment of lysosomal storage disorders was entirely supportive. A new enzyme replacement therapy has become available in Gaucher's disease, a lipid storage disorder that is due to a genetic defect of beta-glucocerebrosidase. Intravenous infusions of modified beta-glucocerebrosidase has produced clinical improvement in Gaucher patients, with regression of organomegaly and increase in blood counts. At the Children's Hospital of Mainz 13 patients (6 children and 7 adults) were treated with alglucerase on a high-dosage regimen (60 units per kilogram every two weeks). A decrease in liver and spleen size was observed 4 to 6 months after commencement of therapy. Hemoglobin and the number of platelets increased. In some cases, a reduction of the dosage was possible after a year of enzyme replacement-therapy. A growth spurt was observed in the children. The availability of enzyme replacement therapy is limited by its high cost; however, in the future gene transfer may become the treatment of choice.

Adolescent↗
PubMed1997

Identification of 31 novel mutations in the N-acetylgalactosamine-6-sulfatase gene reveals excessive allelic heterogeneity among patients with Morquio A syndrome.

Mutation analysis of the N-acetylgalactosamine-6-sulfate sulfatase gene was performed in a group of 35 patients with mucopolysaccharidosis type IVA from 33 families, mainly of European origin. By nonradioactive SSCP screening, 35 different gene mutations were identified, 31 of them novel. Together they account for 88.6% of the disease alleles of the patients investigated. The vast majority of the gene alterations proved to be point mutations, 23 missense, 2 nonsense, and 3 affecting splicing. Six small deletions (1-27 bp) and one insertion were also characterized. In a Polish family, two mildly affected siblings were compound heterozygotes for R94G and R259Q. Their mother was homozygous for the latter point mutation, leading to enzyme deficiency and a borderline disease phenotype.

Adolescent↗
PubMed1997

Identification of 16 sulfamidase gene mutations including the common R74C in patients with mucopolysaccharidosis type IIIA (Sanfilippo A).

Mucopolysaccharidosis type IIIA (MPS IIIA or Sanfilippo A disease) is a storage disorder caused by deficiency of the lysosomal enzyme sulfamidase. Mutation screening, using SSCP/heteroduplex analyses on cDNA and genomic DNA fragments, was performed in a group of 42 European patients. Sixteen of the 17 different gene mutations characterized have not been previously described. The spectrum of gene lesions consists of two 1-bp deletions (1091delC, 1093delG), an 18-bp duplication (421ins18), a splice site mutation (IVS2-2A-->G), and 13 different missense point mutations. As in other lysosomal storage disorders, the phenotypic heterogeneity is associated with a considerable genetic heterogeneity. The missense mutation R74C, which alters an evolutionary conserved amino acid in the active site of the enzyme, was found on 56% of alleles of 16 Polish patients, whereas it was less frequent among German patients (21% of disease alleles). R245H, a previously reported common mutation, represents 35% of disease alleles in German patients, but only 3% in Polish patients. As the combined frequency of the common mutations (R74C and R245H) in German and Polish populations exceeds 55%, screening for these two mutations will assist molecular genetic diagnosis of MPS IIIA and allow heterozygote testing in these populations.

Binding Sites↗
PubMed1997

Molecular analysis of Gaucher disease: distribution of eight mutations and the complete gene deletion in 27 patients from Germany.

Gaucher disease is the most common lysosomal storage disease with a high prevalence in the Ashkenazi Jewish population but it is also present in other populations. The presence of eight mutations (1226G, 1448C, IVS2+1. 84GG, 1504T, 1604T, 1342C and 1297T) and the complete deletion of the beta-glucocerebrosidase gene was investigated in 25 unrelated non-Jewish patients with Gaucher's disease in Germany. In the Jewish population, three of these mutations account for more than 90% of all mutated alleles. In addition, relatives of two patients were included in our study. Restriction fragment length polymorphism analysis and sequencing of PCR products obtained from DNA of peripheral blood leukocytes was performed for mutation analysis. Gene deletion was detected by comparison of radioactively labelled PCR fragments of both the functional beta-glucocerebrosidase gene and the pseudogene. Among the unrelated patients, 50 alleles were investigated and the mutations identified in 35 alleles (70%), whereas 15 alleles (30%) remained unidentified. The most prevalent mutation in our group of patients was the 1226G (370Asn-->Ser) mutation, accounting for 18 alleles (36%), followed by the 1448C (444Lcu-->Pro) mutation, that was found in 12 alleles (24%). A complete gene deletion was present in two alleles (4%). The IVS1+2 (splicing mutation), the 1504T (463Arg-->Cys) as well as the 1342C (409Asp-->His) mutations were each present in one allele (2%). None of the alleles carried the 84GG (frame-shift), 1604A (496Arg-->His) or the 1297T (394Val-->Leu) mutation. This distribution is different from the Ashkenazi Jewish population but is similar to other Caucasian groups like the Spanish and Portuguese populations. Our results confirm the variability of mutation patterns in Gaucher patients of different ethnic origin. All patients were divided into nine groups according to their genotype and their clinical status was related to the individual genotype. Genotype/phenotype characteristics of the 1226G, 1448C, and 1342C mutations of previous studies were confirmed by our results.

Adolescent↗
PubMed1997

Expression of amyloid precursor protein mRNA isoforms in rat brain is differentially regulated during postnatal maturation and by cholinergic activity.

Pathological processing of the amyloid precursor protein (APP) is assumed to be responsible for the amyloid deposits in Alzheimer-diseased brain tissue, but the physiological function of this protein in the brain is still unclear. The aim of this study is to reveal whether the expression of different splicing variants of APP transcripts in distinct brain regions is driven by postnatal maturation and/or regulated by cortical cholinergic transmission, applying quantitative in situ hybridization histochemistry using 35S-labeled oligonucleotides as specific probes to differentiate between APP isoforms. In cortical brain regions, the expression of both APP695 and APP751 is high at birth and exhibits nearly adult levels. The developmental expression pattern of cortical APP695 displays a peak value around postnatal day 10, while the age-related expression of APP751 demonstrates peak values on postnatal days 10 and 25, with the highest steady state levels of APP751 mRNA on day 25. During early development, the cortical laminar distribution of the APP695, but not APP751, mRNA transiently changes from a more homogeneous distribution at birth to a pronounced laminar pattern with higher mRNA levels in cortical layer III/IV detectable at the age of 4 days and persisting until postnatal day 10. The distinct age-related changes in cortical APP695 and APP751 mRNA levels reflect the functional alterations during early brain maturation and suggest that APP695 might play a role in establishing the mature connectional pattern between neurons, whereas APP751 could play a role in controlling cellular growth and synaptogenesis. Lesion of basal forebrain cholinergic system by the selective cholinergic immunotoxin 192IgG-saporin resulted in decreased levels of APP695 but not APP751 and APP770 transcripts by about 15-20% in some cortical (cingulate, frontal, parietal, piriform cortex), hippocampal regions (CA1, dentate gyrus), and basal forebrain nuclei (medial septum, vertical limb of diagonal band), detectable not earlier than 30 days after lesion and persisting until 90 days postlesion, suggesting that the nearly complete loss of cortical cholinergic input does not have any significant impact on the expression of APP mRNA isoforms in cholinoceptive cortical target regions.

Acetylcholinesterase↗
PubMed1997

Anesthetic efficacy of the intraosseous injection of 2% lidocaine (1:100,000 epinephrine) and 3% mepivacaine in mandibular first molars.

OBJECTIVES: This study compared the anesthetic efficacy of a primary intraosseous injection of 2% lidocaine with 1:100,000 epinephrine and 3% mepivacaine in human mandibular first molars. Injection pain and healing postoperatively were also assessed for the intraosseous injection. STUDY DESIGN: With the use of a repeated-measures design, 42 subjects randomly received intraosseous injections of 1.8 ml of 2% lidocaine with 1:100,000 epinephrine or 1.8 ml of 3% mepivacaine in a double-blind manner at two successive appointments. The first molar and adjacent teeth were blindly tested with an electric pulp tester at 2-minute cycles for 60 minutes. Anesthetic success was defined as no subject response to the maximum output of the pulp tester (80 reading) for two consecutive readings. RESULTS: Anesthetic success occurred in 74% of the first molars with 2% lidocaine with 1:100,000 epinephrine and in 45% with 3% mepivacaine. The difference was statistically significant (p < 0.05). Overall, onset was rapid for the intraosseous injections, the duration of pulpal anesthesia steadily declined over the 60 minutes, the majority of the subjects had no pain or mild pain with perforation and solution deposition, and 5% of the subjects had delayed healing at the perforation sites. CONCLUSIONS: The results of this study indicate that the primary intraosseous injection of 2% lidocaine with 1:100,000 epinephrine is more successful and results in a longer duration of pulpal anesthesia as compared with 3% mepivacaine in noninflamed mandibular first molars. Most subjects reported no or mild pain during perforation and injection.

Adolescent↗
PubMed1997

Anesthetic efficacy of the supplemental intraosseous injection of 3% mepivacaine in irreversible pulpitis.

OBJECTIVE: To determine the efficacy of a supplemental intraosseous injection of 3% mepivacaine in mandibular posterior teeth with irreversible pulpitis. Intraosseous injection pain, subjective heart rate increase, and pain ratings during endodontic treatment were also assessed. STUDY DESIGN: Forty-eight patients with irreversible pulpitis received conventional inferior alveolar nerve blocks. Electric pulp testing was used to determine pulpal anesthesia. Patients who were positive to the pulp testing, or negative to pulp testing but felt pain during endodontic treatment, received an intraosseous injection of 1.8 ml of 3% mepivacaine. A second intraosseous injection of 3% mepivacaine (1.8 ml) was given if the first injection was unsuccessful. RESULTS: Seventy-five percent of patients required an initial intraosseous injection because of failure to gain pulpal anesthesia. The inferior alveolar block was 25% successful; the first intraosseous injection increased success to 80%. A second intraosseous injection further increased success to 98%. These differences were significant (p < 0.05). Eight percent (4/48) of the initial intraosseous injections resulted in solution being expressed into the oral cavity: these were considered technique failures. CONCLUSIONS: For mandibular posterior teeth with irreversible pulpitis, a supplemental intraosseous injection of 3% mepivacaine increased anesthetic success. A second intraosseous injection, when necessary, further improved success.

Adolescent↗
PubMed1997

Is patch testing necessary in vulval vestibulitis?

Allergic contact dermatitis has been suggested as a possible cause of vulval vestibulitis, a condition of unknown aetiology characterized by burning, stinging and dyspareunia, with symptoms localised to the vestibule. To examine this relationship, 30 women with vulval vestibulitis were patch tested using a standard series of contact allergens and a special series relevant to perianal and vulval disorders. Other potential allergens identified by the patients as causing aggravation were also included. There were 5 positive reactions, 4 to nickel and 1 to fragrance mix, though none of these reactions were considered relevant. Our results suggest that allergic contact dermatitis is unlikely to be a primary factor in the development or persistence of vulval vestibulitis. Patch testing patients with vulval vestibulitis cannot routinely be recommended.

Administration, Cutaneous↗
PubMed1997

Dispersal behavior of adult snow melt mosquitoes in the Upper Rhine Valley, Germany.

The dispersal behavior of female snow melt mosquitoes was studied in two forests in Rhineland-Palatinate, Germany, from April to August 1993. Both CDC-light-traps and human bait collections were used to collect mosquitoes. Sampling sites were chosen along a west-east and a north-south transect in treated and untreated parts of a forest with a village in its center. Around this settlement, breeding sites within a radius of 1.5 to 2.5 km were treated. It could be shown that this buffer zone is sufficient to prevent a nuisance caused by snow melt mosquitoes in the village. The results lead to the conclusion that snow melt mosquitoes do not regularly migrate over large distances but stay near their breeding sites. In a detailed study of the behavior of Aedes rusticus, it could be observed that these mosquitoes were resting in the interior of the forest during daytime and leaving it with increasing dusk up to 50 m from the forest edge. A comparison of landing rate counts near a row of trees and in the open field showed higher activity near the row of trees indicating visual orientation of the mosquitoes. Although the Ae. rusticus females left the forest regularly, no nuisance occurred in nearby villages. The treatment of breeding sites near settlements appeared to be sufficient to prevent a nuisance caused by the snow melt mosquitoes.

Aedes↗
PubMed1997

Peripheral opioid analgesia in teeth with symptomatic inflamed pulps.

The purpose of this study was to investigate the ability of low-dose fentanyl to produce analgesia when administered via the periodontal ligament injection in teeth with symptomatic, inflamed pulps. All subjects presented for emergency treatment with moderate to severe pain and had a posterior tooth with a clinical diagnosis of irreversible pulpitis. Twenty subjects randomly received either 10 micrograms fentanyl citrate or saline placebo via the periodontal ligament injection in a double-blind manner. The subjects rated their pain prior to injection and rated pain intensity and pain half gone for 59 min postinjection. Low-dose fentanyl delivered via the periodontal ligament injection in inflamed teeth provided significantly greater analgesia than the saline placebo (P < 0.05). Since the dose of fentanyl used was less than the dose required to provide analgesia by a central mechanism, the results of this study may be consistent with a peripheral opioid mechanism of action.

Adult↗
PubMed1996

Neuraminidase assay in cultured human fibroblasts: in situ versus in vitro procedures.

Further investigations have been carried out to characterize a published procedure of neuraminidase assay, in which the activity is measured directly on the cell culture layer. The pH optimum was 4.0. A Vmax value of 130 nmol/mg/h and a K(m) of 0.3 mmol/l were found. During incubation in the acid buffer, arylsulphatase activity was released into the medium, whereas neuraminidase activity remained attached to the cells. The in situ method allowed an unequivocal diagnosis of primary and secondary neuraminidase deficiencies. Because of its simplicity and reliability, the method appears useful as a routine method in clinical laboratories.

Adult↗
PubMed1996

Clinical and neuroradiological findings in classic infantile and late-onset globoid-cell leukodystrophy (Krabbe disease).

In the present study the clinical course and imaging of early and late-onset forms of Krabbe disease are analyzed. We report on 11 patients with a biochemical diagnosis of galactosyl ceramide beta-galactoside deficiency. Two presented as the classic infantile form and died within the second year of life. In 9 children the first clinical signs, such as gait difficulties and visual failure, started after age 2 years. All these patients developed slow regression of motor and mental capacities, and most of them died within their first decade. In patients of both groups computed tomography (CT) and magnetic resonance imaging (MRI) were performed. In the late-onset form, hypodensities of the central white matter and pyramidal tracts were the leading radiological signs, whereas in the early-onset form, hyperdensities and cerebellar white matter lesions were also detected. From our results it becomes clear that variability of Krabbe disease refers not only to clinical manifestation but also to CT and MRI findings. Better knowledge of phenotypic and radiological diversity will help to understand the pathogenesis of the disease.

Age of Onset↗