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Biomedical subjects

L G Schneider

Publications and source records attributed to L G Schneider.

At least 19 recordsLinked to original sources
PubMed2001

Unstimulated salivary flow rates of young children.

OBJECTIVE: Studies on salivary flow rates in human beings have mainly been carried out with adults. The purpose of this study was to determine the unstimulated salivary flow rates of children 4 to 7 years old. In addition, the relative contributions of the variables age, gender, race, height, body weight, dentition status, use of prescription medication, and health status (information obtained from parents) to the unstimulated salivary flow rates of children were also studied. STUDY DESIGN: Data were obtained from children (n = 447) at 2 sites in the United States (site 1, southeast Michigan; site 2, northern Michigan) and at 5 sites in Brazil (site 3, Porto Alegre; site 4, São Paulo; site 5, Belém; and sites 6 and 7, sites in Rio de Janeiro). In northern Michigan (site 2) the participants were cognitively or developmentally disabled, or both. In Rio de Janeiro (site 7), a group of 8- to 12-year-olds served as a control group. Saliva samples were collected for 3 minutes between 9 AM and noon in the spring or summer, and the saliva rate was determined gravimetrically. Data were analyzed by analysis of variance, bivariate analysis, and regression analysis. RESULTS: The secretion rates at the 7 sites were (in milliliters per minute) 0.19 +/- 0.15, 0.23 +/- 0.28, 0.34 +/- 0.23, 0.48 +/- 0.37, 0.25 +/- 0.27, 0.37 +/- 0.28, and 0.61 +/- 0.34, respectively. There were significant differences among sites (P <.0001). The older group (site 7) had flow rates that were significantly higher than the flow rates of any other group. In addition, children from Michigan (sites 1 and 2) had significantly lower rates than most groups of children in Brazil. Girls had lower unstimulated salivary flow rates than boys did at all the sites, but the differences were not statistically significant. Race was shown not to affect the flow rates. The use of any prescription medication by children in the previous 3 months was associated with lower salivary flow rates than were found in children not using prescription medication. Children who were in good health and who had no previous medical conditions had higher flow rates--but not significantly so. Higher flow rates occurred in children with mixed dentition than in children with primary dentition, although again the differences were not statistically significant. Regression analysis revealed weight to be of significance in explaining the variability of the unstimulated salivary flow rates at 2 sites, height at 1 site, the use of prescription medication at 2 sites, and age at 1 site. CONCLUSIONS: The unstimulated salivary flow rates in children in the northern United States are comparable with those reported for Japanese children, whereas the flow rates of children in Brazil are comparable with those reported for North American and European adults. In addition, none of the demographic variables/parameters tested contributed consistently to the variability of the unstimulated salivary flow rates in children at the 7 sites assessed in this study.

Age Factors↗
PubMed2001

A model for clinical evaluation of the effect of antimicrobial agents on carious dentin.

PURPOSE: To evaluate, longitudinally, the effect of a chlorhexidine varnish on the proteolytic activity of dentin caries in vivo. MATERIALS AND METHODS: 20 permanent molars and 8 primary molars with carious lesions in dentin were studied in subjects 18-35 yrs old (n=20), and 5-6 yrs old (n=8) respectively. These lesions were clinically evaluated according to texture and color. Carious dentin specimens were obtained by means of biopsies performed with a #4 carbide bur at the initial visit (TO) before application of a 10% chlorhexidine varnish and 2, 4, 8, and 12 wks thereafter. The dentin biopsies were immersed in Sorensen's buffer, vortexed for 30 s, and mixed with a 1.67 mM solution of n-benzoyl-DL-arginine-naphthylamide (BANA), a substrate for proteolytic enzymes. Samples were incubated overnight at 37 degrees C and color was developed with 0.1% fast garnet. The optical density (OD) of reaction mixtures was recorded photometrically. All teeth were grouped for analysis, as Mann-Whitney tests revealed no statistically significant differences between median values for OD for both age groups. ANOVA was used to compare progressive inhibition of proteolytic activity in dentin caries samples over time. RESULTS: The average proteolytic activity at the dentin substrates (OD) at TO and 2, 4, 8 and 12 wks thereafter were 0.794+/-0.089, 0.741+/-0.071, 0.676+/-0.087, 0.600+/-0.094, and 0.508+/-0.108 respectively. The chlorhexidine varnish mediated a significant inhibition of the proteolytic activity present in dentin caries after 12 wks (P<0.0001). At T0, 100% of the carious lesions examined were characterized as soft upon exploration. After 12 wks, 54% (15/28) of the lesions were partially hardened and 46% (13/28) hardened/nonprogressing. The dentin color was yellow/light brown in 100% of the lesions at baseline, and dark brown/black in 86% (24/28) after 12 wks. CLINICAL SIGNIFICANCE: This study demonstrated that chlorhexidine varnishes arrested active caries in vivo and inhibited the proteolytic activity present in these lesions. These findings strengthen the rationale for including chlorhexidine in the overall treatment strategy for patients with high caries activity.

Adolescent↗
PubMed2000

Medication usage and dental caries outcome-related variables in HIV/AIDS patients.

The purpose of this study was to access current medication usage by HIV/AIDS patients and its effects on dental caries and on unstimulated salivary flow rates. Thirty females and 127 males (mean age = 39.6 +/- 7.4 years), of whom 46% were White/Non-Hispanic, 39% African-American, and 15% Hispanic, were examined and interviewed at the Bering Dental Clinic, Houston, Texas. The mean time in years after seroconversion was 5.4 +/- 4.1. Calibrated examiners performed dental caries examination (DMFS) with dental explorers and bitewing radiographs. Interviews were carried out with pretested questionnaires, and medication usage was assessed by illustrative examples of HIV/AIDS medications. Salivary flow rates were determined gravimetrically (mL/min). Bivariate analysis and analysis of variance (ANOVA) were used to analyze the data. Because there were no race or gender effects on dental caries outcome variables or salivary flow rates, separate logistic regression models for medication usage were generated, which were adjusted for age and CD4+ cell counts. Patients who, currently, were receiving antiretroviral therapy (ART) had a lower occurrence of dental caries than patients not taking these medications. An unexpected finding in the lower caries rate group was a decrease in salivary flow rates, which was a probable oral side effect of ART. It appears from this cross-sectional study that systemic medication for the management of HIV disease has no significant detrimental effect on the dentition.

Adult↗
PubMed1998

Tramadol hydrochloride: analgesic efficacy compared with codeine, aspirin with codeine, and placebo after dental extraction.

Tramadol hydrochloride is a novel, centrally acting analgesic with two complementary mechanisms of action: opioid and aminergic. Relative to codeine, tramadol has similar analgesic properties but may have fewer constipating, euphoric, and respiratory depressant effects. A two-center randomized double-blind controlled clinical trial was performed to assess the analgesic efficacy and reported side effects of tramadol 100 mg, tramadol 50 mg, codeine 60 mg, aspirin (ASA) 650 mg with codeine 60 mg, and placebo. Using a third molar extraction pain model, 200 healthy subjects were enrolled in a 6-hour evaluation after a single dose of drug. Of the 200 patients enrolled, seven provided incomplete efficacy data or discontinued prematurely and one was lost to follow-up. Using standard measures of analgesia, including total pain relief score (TOTPAR), maximum pain relief score (MaxPAR), sum of pain intensity difference scores (SPID), peak pain intensity difference (Peak PID), remedication, and global evaluations, all active treatments were found to be numerically superior to placebo. ASA/codeine was found to be statistically superior to placebo for all measures of efficacy. Tramadol 100 mg was statistically superior to placebo for TOTPAR, SPID, and time of remedication, whereas tramadol 50 mg was statistically superior to placebo onlyfor remedication time. Codeine was not found to be statistically superior to placebo for any efficacy measure. A greater TOTPAR response compared with all other active measures was seen for ASA/codeine during the first 3 hours of study. The 6-hour TOTPAR scores for the tramadol groups and ASA/ codeine group were not significantly different. Gastrointestinal side effects (nausea, dysphagia, vomiting) were reported more frequently with tramadol 100 mg, ASA/ codeine, and codeine 60 mg than with placebo.

Adolescent↗
PubMed1995

Rabies virus vaccines.

Many years of research and observations on bait uptake, efficacy, behavioural studies of foxes, reduction and elimination of rabies, population dynamics of foxes following oral vaccination, as well as annual exchanges of researchers' experiences, formed the scientific background for field trials extending over many years. These are the most extensive field studies for the testing of a rabies vaccine so far. The use of the techniques and strategies of oral immunisation of foxes against rabies using SAD B19 can eliminate wildlife rabies among foxes and raccoon dogs, as European experience has shown. The disease then also disappears completely in domestic animals and man.

Administration, Oral↗
PubMed1990

Molecular cloning and complete nucleotide sequence of the attenuated rabies virus SAD B19.

Complementary DNA spanning the entire genome of the attenuated rabies virus strain SAD B19 which is used for oral immunization of foxes in Europe was cloned and sequenced. The viral genome comprises 11,928 nucleotides and encodes the five viral proteins N, NS, M, G, and L. Deduced protein sequences are highly similar to those of the pathogenic PV strain, homologies ranging from 90.6% for the M to 98.6% for the L protein. The five cistrons are separated by intergenic regions of 2, 5, 5, and 24 nucleotides, respectively. The G transcription stop/polyadenylation consensus signal in SAD B19 is destroyed by a deletion of three A residues. The strong conservation of both noncoding and coding nucleotide sequences indicates a high selective pressure on the primary structure of rabies virus genomic RNA.

Amino Acid Sequence↗
PubMed1990

Identification of fox rabies by a monoclonal antibody directed against nucleocapsid of a street rabies virus.

Hybridomas were prepared by fusion of spleen cells from BALB/c mice immunized with dog rabies isolates from Nigeria with P3x63Ag8 myeloma cells. More than 69 hybridomas secreted antinucleocapsid (antiNC) antibodies when tested with homologous viruses by indirect immunofluorescence. One hybridoma (Z144-88) was found which secreted antiNC antibody that reacted negatively with fox rabies isolates from the Federal Republic of Germany, Switzerland and France and with rabies-related viruses and European bat isolates. It reacted positively with other strains/isolates of rabies virus. It is possible to use this antiNC monoclonal antibody (mab) for the investigation of fox rabies outbreaks in Europe.

Animals↗
PubMed1990

Antigenic characterization of street rabies virus isolates from Nigeria using monoclonal antibodies.

Twenty isolates of street rabies virus were recovered in mouse neutroblastoma cells from 84 rabies suspect brain specimens from Nigeria dogs and a cat. They were characterized with the Tübingen monoclonal antibody panels directed against nucleocapsid and glycoprotein antigens. Antigenic variations were detected both with antinucleocapsid (anti-NC) and antiglycoprotein (anti-GP) monoclonal antibodies (mabs). One isolate reacted positively with anti-NC mab P41 which hitherto has been known to react positively with polar rabies. Another isolate did not react with anti-NC mab 187.5; a reaction normally seen with ERA/SAD strains of rabies virus. With anti-GP mabs it was possible to group the isolates by their area of origin. Isolates from Plateau State were not neutralized by anti-GP mabs ERA 543 and P44.7.2. The isolates studied had glycoprotein antigenic patterns different from the pattern for low egg passage (LEP) Flury strain vaccine virus used in Nigeria for immunization of dogs.

Animals↗
PubMed1990

Ineffectiveness and comparative pathogenicity of attenuated rabies virus vaccines for the striped skunk (Mephitis mephitis).

Three attenuated rabies virus vaccines (SAD-B19, ERA/BHK-21, AZA 2) were compared for efficacy and safety in the striped skunk (Mephitis mephitis) by the oral and intranasal routes. The SAD-B19 and ERA/BHK-21 vaccines were given orally; all three vaccines were given intranasally. Oral administration of SAD-B19 and ERA/BHK-21 vaccines induced neither seroconversion nor significant protection against rabies challenge. One skunk which consumed a SAD-B19 vaccine-laden bait succumbed to vaccine-induced rabies. Intranasal instillation of the three vaccines resulted in the deaths of two of six (AZA 2), three of six (ERA/BHK-21) and six of six (SAD-B19) skunks.

Administration, Intranasal↗
PubMed1990

Oral immunization of foxes against rabies: practical experiences of a field trial in the Federal Republic of Germany.

The development of and the logistics used in campaigns for the oral immunization of foxes against rabies in the Federal Republic of Germany are described. The "Bavarian Model", which is outlined in detail, shows how local hunters were recruited for bait distribution and control measures at practically no cost. Over 10 million baits have been distributed in this way by hundreds of thousands of hunters in the Federal Republic of Germany as well as in the other European countries that participated in this large-scale field trial. As a result of the trial, rabies has been reduced or even eradicated in large parts of the Federal Republic of Germany.

Administration, Oral↗
PubMed1989

Oral vaccination of raccoons (Procyon lotor) with an attenuated (SAD-B19) rabies virus vaccine.

Unlike previous reports to the contrary, raccoons (Procyon lotor) were successfully vaccinated against rabies with a liquid SAD-B19 attenuated virus vaccine administered per os and given in vaccine-laden baits. There was neither evidence of vaccine-induced rabies in raccoons nor in a limited safety trial with opossums (Didelphis virginiana) given SAD-B19. Protection from lethal street rabies virus infection was not absolute: only three of nine raccoons given 1 x 10(6.0) TCID/ml were protected versus five of 10 raccoons given 1 x 10(7.0) TCID/ml of SAD-B19 and challenged 4 mo after consumption of vaccine-laden baits. Six of eight raccoons consuming 1 x 10(8.8) TCID/ml of SAD-B19 vaccine in baits survived street rabies virus challenge 2 mo postvaccination. Raccoon survivorship was not wholly dependent upon rabies virus-neutralizing antibody titer on the day of challenge. Vaccinated raccoons demonstrated a prominent anamnestic response within 1 wk following challenge. Surviving raccoons were observed for a minimum of 3 mo following street rabies virus challenge with neither clinical nor pathologic evidence of rabies. The SAD-B19 rabies vaccine administered within baits in captivity appears less effective for raccoons than for its demonstrated efficacy in the immunization of free-ranging foxes (Vulpes vulpes) in Europe.

Administration, Oral↗
PubMed1986

[Experiences with oral immunization of foxes against rabies in Hesse].

Since spring 1983 a field trial to immunize foxes by the oral route against rabies has been carried out in a heavily infected area of Hessen measuring about 1,500 km2. The vaccine strain SAD B 19, produced by the Federal Research Institute for Animal Virus Diseases at Tübingen and filled into 2 ml aliquots, was inserted into chicken heads and distributed by forest rangers in the trial area, 15 baits per km2. Up to the present day five baiting campaigns, two per year in spring and autumn, have been completed and in all 110,000 vaccine baits additionally marked with 150 mg tetracycline were layed out. Four baitings have been previously evaluated. With the exception of some rabies cases on the border to the unvaccinated region in the northwest, rabies was reduced impressively. A secondary outbreak in the region of Hausen/Kiedrich, caused by an extremely high density of the fox population, was eradicated by increasing the baits to 25 per km2. The number of rabies cases, which amounted to 238 within 15 months prior to the vaccination trial, went down from 38 in the first 6 months to 6 cases after the fourth baiting. As innocuity control 2,273 wild and domestic animals from the vaccination area were examined for the presence of the vaccine virus. The results were always negative indicating that rabies strain SAD B 19 had not established an infective cycle in wildlife. As could be shown by the marker studies, an average of 78 per cent of the foxes (variation of the baitings from 62 per cent to 82 per cent) had taken up one or more baits. Seroconversion had been achieved in 65 per cent of the foxes (variation from 43 per cent to 70 per cent) as demonstrated by the presence of neutralizing antibodies. From experiences in Switzerland it can be expected, that rabies will be extinguished, if 50 per cent of the population are successfully immunized. This value has been surpassed in the field trial in Hessen. These very promising results have led to the project of an enlargement of the vaccination area to 12,000 km2. The neighbouring states of Rheinland-Pfalz and Nordrhein-Westfalen have joined in this effort, which has started in autumn 1985 with a new artificial vaccine bait developed at the Tübingen research institute.

Administration, Oral↗
PubMed1984

The effects of topical steroidal and systemic nonsteroidal anti-inflammatory drugs on experimental gingivitis in man.

Retrospective studies in man and prospective studies in animals have indicated that systemically administered anti-inflammatory drugs may decrease plaque-induced inflammation and loss of attachment. The purpose of the present double blind study was to determine the effects of a systemically administered nonsteroidal anti-inflammatory drug and a topically applied steroidal anti-inflammatory drug on experimentally produced gingivitis. Eighteen dental students were brought to a state of optimal gingival health and then divided into three groups. One group received placebo gel to apply topically and placebo capsules. A second group received placebo gel and capsules containing sulindac, a nonsteroidal anti-inflammatory drug. The third group received a topical steroidal gel and placebo capsules. All subjects refrained from home care for 22 days in the maxillary right quadrant. Results of the study indicate that the topical steroidal drug significantly inhibited gingival inflammation while the systemically administered nonsteroidal drug had no apparent effect.

Administration, Topical↗
PubMed1984

Rabies in the Federal Republic of Germany, 1950-81: the influence of landscape.

Rabies statistics for 1950-81 were studied to investigate regional differences in the occurrence of rabies in the Federal Republic of Germany. At the level of Landkreis (administrative unit with a mean area of 1013 km(2)), four basic patterns of rabies incidence were identified: insignificant occurrence, low undulations, intermittent peaks, and high oscillations. The distribution of these four epidemiological patterns of rabies was geographically localized. Insignificant occurrence of rabies was found almost exclusively on land under 100 m above sea level with less than 10% forest cover. High oscillations in rabies occurrence were found most often in areas over 200 m above sea level with an average of at least 35% forest cover.

Altitude↗
PubMed1983

Causes of abnormal vaginal bleeding in a Family Practice Center.

Abnormal vaginal bleeding had an incidence of 20.0 per 1,000 woman-years in patients of the Kanawha Valley Family Practice Center. Contraception-related bleeding was the most common cause, accounting for 28 percent of the cases. Anovulatory and dysfunctional uterine bleeding were the next most common causes, accounting for 15 percent and 13 percent, respectively. All three causes were uncommon in women aged 41 to 55 years, and absent in women older than 55 years. Perimenopausal bleeding, the dominant cause of abnormal vaginal bleeding in the 41-to-55-year group, was also absent in women older than 55 years of age. In women 56 years of age or older, endometrial carcinoma caused 28.6 percent of the bleeding; it did not occur in any other group.

Adult↗