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Biomedical subjects

B Köhler

Publications and source records attributed to B Köhler.

At least 55 records · Page 3Linked to original sources
PubMed1995

Amplification of Mycobacterium tuberculosis from peripheral blood.

To determine the value of the PCR assay of lymphomonocytic blood cells for the diagnosis of pulmonary tuberculosis, we compared, in a prospective study, PCR results with results of conventional diagnostic methods of Mycobacterium tuberculosis detection. Clinical investigators who were unaware of the PCR data classified 162 immunocompetent patients, who had been hospitalized because of suspected pulmonary tuberculosis, in accordance with the recommendations of the American Thoracic Society (ATS). By testing blood samples from these patients for mycobacterial DNA with three different PCR systems, we were able to demonstrate that nonquantitative PCR of peripheral blood leukocytes is of little value for the specific diagnosis of pulmonary tuberculosis. However, semiquantitative PCR assays might have some significance since we found an increasing level of mycobacterial DNA copies in blood from patients classified in ATS groups 2 to 5.

Base Sequence↗
PubMed1995

Acid production by human strains of Streptococcus mutans and Streptococcus sobrinus.

Acid production by washed suspensions of human strains of Streptococcus mutans (n = 18) and Streptococcus sobrinus (n = 12) was measured. The strains were isolated from infants and adolescents with varying caries experience. Some of these strains and two laboratory strains (1 S. mutans and 1 S. sobrinus) had been tested in an earlier study for their cariogenicity in hamsters. Further, 3 Streptococcus sanguis strains and 1 S. sobrinus laboratory strain were included. Acid production was determined in repeated titration experiments at a constant pH of 5.5. Higher mean acid production activities (p < 0.05) were obtained by S. sobrinus compared with both S. mutans and S. sanguis. However, large variations among the strains were found both between and within the species. No clear relationship was found between the glycolytic activity of strains and the caries prevalence of the children from whom the strains had been isolated or the caries scores in a hamster model. In conclusion, although both S. mutans and S. sobrinus have aciduric and acidogenic properties, it is difficult to relate the acid production activity of pure cultures in vitro to the caries process in vivo.

Acids↗
PubMed1995

[Dermatophilus congolensis infection in Brandenburg].

At first time Dermatophilus (D.) congolensis-infection was diagnosed in Brandenburg in 3 sheep herds and in one horse, which had contact to diseased sheep. The causative agent was introduced from West-Germany probably. Cause of the disease was influenced by a longer rain period and by secondary infections through Staph. aureus var. ovis. The morbidity came up to 90%, the mortality of lambs was 10%. Clinical picture, diagnostic and control of the disease are described. Economical losses are caused by disturbances of the development and deaths of animals mainly. Treatment of sheep was successful with Terramycin LA or 200 mg Oxytetracycline by i.m. injection of 1 ml within 7 days. All isolated strains of D. congolensis caused beta-hemolysis and liquidation of Löffler-Medium (heated denatured serum of cattle), and gelatin and fermented glucose and fructose to acid.

Actinomycetales↗
PubMed1995

Artefacts caused by dental filling materials in MR imaging.

An investigation regarding possible artefacts from dental filling materials in MR imaging is presented including 9 types of such materials from various manufacturers. Freshly extracted teeth were prepared and the filling materials were handled according to manufacturers' instructions. The teeth were encapsulated into a gel phantom based on de-ionized water, Ni (NO3)2 and polysaccharide agarose powder. The investigation was performed with a standard head coil and a 1.5 T MR unit. Images acquired with various combinations of parameters from different sequences were visually analysed regarding possible artefacts. The investigation showed that only one of the materials caused significant artefacts. The gel phantom was found to be a valuable means for examination of artefacts from small samples, and can be recommended as a standard technique for this purpose.

Acrylic Resins↗
PubMed1994

Influence of caries-preventive measures in mothers on cariogenic bacteria and caries experience in their children.

Preventive measures, which reduced the salivary level of mutans streptococci in mothers, delayed colonization by these organisms in their children. The preventive programme was discontinued when the children were 3 years old. These children, at the age of 7 years, and their mothers were now examined to determine the effect of the earlier caries-preventive approach. The control mothers had significantly higher levels of salivary mutans streptococci and lactobacilli than the test mothers (p < 0.05). The median level of salivary mutans streptococci was 0.6 x 10(6) c.f.u. (colony-forming units) per ml in the test mothers and 1.3 x 10(6) c.f.u. in the control mothers. The median level of salivary lactobacilli was 10 times higher in control than test mothers (80 x 10(3) and 7 x 10(3) c.f.u. per ml, respectively). Significantly more children of control than test mothers carried mutans streptococci (95 versus 46%) (z-test; p < 0.01). Children of test mothers had lower salivary levels of mutants streptococci and lactobacilli (p < 0.05). Twenty three % of the test children were caries-free, compared with 9% of the control children (z-test; p < 0.01). The mean caries experience of the test children was also significantly lower than that of the control children (defstot 5.2 and 8.6, respectively; p < 0.05). The results show that reduction of the mutans streptococci in the mother during the emergence of the primary teeth in her child has a long-term influence on colonization by these bacteria and the caries experience in the child.

Case-Control Studies↗
PubMed1993

Influence of salivary levels of mutans streptococci on colonization of crown margins: a longitudinal study.

Initial colonization of mutans streptococci in 36 crown margins of 21 patients was studied. Before cementation, salivary concentrations of mutans streptococci and Lactobacillus sp, microorganisms associated with dental caries, were determined. Within 1 week 25% of the selected crown margins in subjects with low salivary levels of mutans streptococci and 89% in subjects with high salivary levels were colonized. High salivary counts of lactobacilli seemed to reflect conditions that enhanced the risk of colonization of mutans streptococci. The results suggest that, before cementation of fixed prosthodontics, measures should be taken to control the salivary concentrations of these organisms to reduce the susceptibility to recurrent caries.

Adult↗
PubMed1993

Caries experience in Icelandic 12-year-old urban children between 1984 and 1991.

In order to evaluate trends in caries experience, a 20% random sample of 12-yr-old residents of Reykjavik, Iceland (252 children) was examined clinically and radiographically in 1991 under conditions consistent with those of the survey conducted in 1984. In addition to caries data, frequency of toothbrushing and use of fluoride dentifrice were recorded. The mean DFT and DFS were 3.0 and 4.1, respectively. The decrease in caries experience reached 60% with an annual fall in DFS of nearly 10%. During the 7-yr period between examinations the decline in DFT and DFS scores averaged 5.2 and 8, respectively, the annual reduction amounting to 0.7 DF teeth or 1.1 DF surfaces per child. The ratio of approximal/occlusal caries and the proportion of approximal caries were similar in both surveys. Fourteen percent of the children were free from manifest caries in 1991, but only 2% in 1984. Polarization between low and high prevalence individuals had intensified. Ninety-five percent of the children brushed their teeth regularly and 97% reported using a fluoride dentifrice.

Child↗
PubMed1993

A longitudinal study of dental caries and cariogenic microflora in a group of young adults from Göteborg.

Caries and cariogenic microorganisms were assessed in a group of young adults over a 3-year period. A 30% random sample comprising 101 individuals aged 18-19 years was re-examined under conditions consistent with the baseline survey 3 years earlier. The means for DFS prevalence and increment were 8.9 and 2, respectively. Continuing polarization of the disease was observed, with mean DFS score reaching 19.9 in the upper 15% of the frequency distribution. Highest caries activity was observed approximally where the increment of manifest and incipient lesions averaged 1.3 and 1.6 surfaces, respectively, as compared to 0.5/0.6 occlusally and 0.2/0.5 bucco-lingually. While the occlusal component continued to dominate DF score with 5.7 surfaces, the prevalence of approximal lesions increased by 48%, averaging 2.7 surfaces. Frequency distribution showed a shift to the right and increasing skewness. The proportion without manifest lesions/restorations had declined by 3%. While only 6% of the dentin lesions/restorations were found in the lowest quartile, 15% of the individuals with highest caries levels accounted for 40% of the total DFS and 58% of the D component. Among the 88 subjects who were saliva sampled, salivary mutans streptococci were detected in 89.7% and lactobacilli in 83%. Forty-one percent of the 18-19-year-olds had high numbers of mutans streptococci (> 5 x 10(5) cfu per ml) as compared to 33% at the age of 15-16-years, while high numbers of lactobacilli (> 10(5) cfu per ml) were recovered in 21.8% as compared to 14.3%. The stability within each range of microorganisms varied depending on the baseline level.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1993

[Example of the concentration of salmonellae in the environment].

During a period of 3 years the occurrence of Salmonellas was cleared up on depots for refuse of households around Berlin. The investigations were carried out by susceptible fractionated enrichment in Medium of Rappaport/Vassiliadis. 15.1% of samples were positive (77 out of 511). Most Salmonellas wer detected in soil samples contaminated with feces of birds. The isolation rate reached his maximum during autumn and winter, when great bird herds lived on the depots. Mainly S. typhimurium, S. saint paul and S. enteritidis were found. S. enteritidis LT 17 (Colindale) was isolated first time in former East Germany. Diseased children of Berlin (West) were the source for contamination of refuse of households and wild birds (crows, gulls) with this Lysotype. During 51 months dissemination of Salmonellas in 4 contaminated feedstuff yeast and animal meal plants was examined. Salmonella were found in 12.02% of samples of feedstuff yeast (2047) and 6.2% of samples of animal meal (337). Characteristically was the seasonal distribution during winter and early spring and the persistence of the same serotypes for years. Recontamination by the environment was the main reason for the occurrence of Salmonella. Regular examination of filter dust samples of all production units was a very effective way for detection of Salmonella contamination in feed plants. S. enteritidis was demonstrated in the environment of an animal meal factory 18 months after his shutdown.

Animal Feed↗
PubMed1993

[Aspects of long-term management of children with myelomeningocele. Analysis of the last 10 years from the neuropediatric-neurosurgical viewpoint].

BACKGROUND: Both the use of a selective policy of treatment of newborns with myelomeningocele and the right time of back closure are still controversially discussed. We report our experiences in the long-term care of children with myelomeningocele. METHODS: 103 newborns with myelomeningocele (n = 94) and meningocele (n = 9) born 1980 to 1990 and cared for regularly at the Olgahospital's pediatric clinic were followed up from the neuropediatric-neurosurgical point of view. Postpartum we predominantly practised a selective policy of treatment. RESULTS: 15 of 21 children (71.4%) not operated on died during the first days or months of life, 6 (28.6%) survived. 70 were operated selectively, of which 9 (12.9%) died, 61 (87.1%) survived with mainly good result. There were no differences in the survival rate and frequency/type of postoperative complications with respect to the time of the back closure. 31 children with myelomeningocele (33%) had CNS anomalies other than the Arnold-Chiari-Malformation, mostly being a dys- or aplasia of the corpus callosum and a deformed ventricle system. These were diagnosed almost exclusively by CT or MRT scan. CONCLUSIONS: We still predominantly practised a selective policy of treatment of newborns with myelomeningocele with mainly good results.

Cerebrospinal Fluid Shunts↗
PubMed1992

Synthesis of the acridone alkaloids glyfoline and congeners. Structure-activity relationship studies of cytotoxic acridones.

Glyfoline (4, 1,6-dihydroxy-10-methyl-2,3,4,5-tetramethoxyacridin-9-one) and its congeners were synthesized for evaluation of their cytotoxicity. A detailed structure-activity relationships (SAR) of these acridone derivatives were also studied. To study the SAR of glyfoline analogues, substituent(s) at C-1 and C-6 and at the heterocyclic nitrogen of glyfoline nucleus were modified. Nitro- and amino-substituted glyfoline analogues were also synthesized to study the effects of substituent(s) (electron-withdrawing vs electron-donating) on their cytotoxicity. These compounds were synthesized via the Ullmann condensation of anthranilic acids with iodobenzenes or 2-chlorobenzoic acids with aniline derivatives. The SAR studies showed that 1-hydroxy-9-acridones were more active than their 1-OMe derivatives against cell growth of human leukemic HL-60 cells in culture. Replacement of NMe of glyfoline with NH or N(CH2)2NEt2 resulted in either total loss or dramatic reduction of cytotoxicity. Glyfoline congeners with nitro function at the A-ring were inactive, while compounds with amino substituent were shown to be cytotoxic in vitro.

Acridines↗
PubMed1992

Effects of Weight Watchers' diet on salivary secretion rate, buffer effect and numbers of mutans streptococci and lactobacilli.

The aim of this investigation was to study how a change to the dietary regimen of the Weight Watchers' (WW) affected salivary secretion rate, buffer effect and number of cariogenic bacteria. Thirty-three women joining the WW were saliva sampled at the evening prior the day of the start of the dietary regimen and after 4 and 8 wk on the dietary regimen. No significant changes were found regarding saliva secretion rate and buffer effect. A significant decrease of salivary numbers of mutans streptococci and lactobacilli occurred. Between the 4th and 8th wk of dietary regimen an increase of cariogenic bacteria occurred but not back to the baseline values. At baseline 15 of the WW carried Streptococcus sobrinus in addition to Streptococcus mutans. The total number of salivary mutans streptococci and lactobacilli was significantly higher in those subjects. In conclusion the dietary regimen of the WW, based on food choice and distributions of meals in agreement with a non-cariogenic diet, reduced the number of cariogenic bacteria in most subjects, but not in all, while the secretion rate and buffer effect remained the same.

Adult↗
PubMed1992

Dental caries in a group of 15 to 16-year-olds from Göteborg. Part I.

301 adolescents aged 15 to 16 years (158 girls and 143 boys) were examined for caries under standardized conditions during the fall and spring terms of 1987/88. Clinical examinations, performed by two calibrated examiners were supplemented with posterior bite-wing radiographs which were assessed by one of the examiners. The mean DFT and DFS scores (incipient lesions included) were 9.8 and 19.4, respectively. The mean DFS score (dentin lesions+restorations) was 6.4. On average 1.9 surfaces had frank cavities or recurrent lesions and 13 surfaces had incipient lesions. Occlusal surfaces contributed 75%, approximal 21% and bucco-linqual 4% to the manifest component of the DFS score (4.8, 1.4 and 0.2 surfaces, respectively). 3% of the incipient lesions were found occlusally, 51% approximally and 46% bucco-linqually (0.4, 6.6 and 5.9 surfaces, respectively). Only 3% of the participants were completely free from caries, whereas 9% had no dentin lesions or restorations. 15% of the subjects with the highest caries prevalence averaged 15.8 dentin lesions or restorations. A tendency towards polarization of low and high caries prevalence groups was observed. Totally 91% of the individuals had occlusal caries, 82% approximal and 76% bucco-lingual, whereas dentin lesions or restorations had 88%, 42% and 14%, respectively.

Adolescent↗
PubMed1992

Mutans streptococci, lactobacilli and caries prevalence in 15 to 16-year olds in Göteborg. Part II.

During the fall of 1987 one hundred and fifty-five 15 to 16-year-olds were examined with regard to caries prevalence, saliva secretion rate and salivary numbers of mutans streptococci and lactobacilli. In 15% of the subjects no mutans streptococci were detected, while 17.7% carried > 10(6) colony forming units (cfu) per ml saliva. The median value was 1.8 x 10(5) cfu per ml saliva. No lactobacilli were detected in 19% of the subjects and 14.3% had > 10(5) cfu per ml saliva. The mean caries prevalence was 21.0, of these 14.1 were incipient lesions. Increased numbers of mutans streptococci and lactobacilli were associated with increasing caries prevalence. Subjects with high numbers of both microorganisms showed about 4 times higher mean caries prevalence than those with low numbers. Streptococcus sobrinus carriers (15%) had both higher mean caries prevalence and a higher proportion of subjects with > 10(6) cfu mutans streptococci per ml saliva than was found in the whole group.

Adolescent↗
PubMed1991

[Atraumatic Clostridium septicum infection in granulocytopenia].

A fatal Clostridium septicum infection occurred in three patients. Case 1. A 55-year-old man died of septicaemia resulting from granulocytopenia of uncertain aetiology; it was associated with perforation of ileal mucosal ulcers. Autopsy revealed neutropenic enterocolitis and diffuse gas formation, especially in the brain, caused by Clostridium septicum. Case 2. A 18-year-old boy developed a caecal invagination during imipenem-induced granulocytopenia. A fulminant postoperative Clostridium septicum infection ended fatally. At autopsy many ulcers were found at the site of invagination with gas formation involving all organs. Case 3. Myonecrosis of the left arm, caused by Clostridium septicum, developed without external cause in a 12-year-old girl with congenital neutropenia. Despite aggressive surgical intervention she died of toxic shock. Autopsy revealed caecal mucosal ulcers as the portal of entry of Clostridium septicum.

Adolescent↗
PubMed1991

Salivary levels of mutans streptococci and lactobacilli in dentate 80- and 85-year-old Swedish men and women.

The number of Streptococcus mutans, Streptococcus sobrinus, and lactobacilli in whole stimulated saliva was examined in 130 dentate 80- and 85-yr-old persons. 88.5% were positive for mutans streptococci and 29% carried greater than 10(6) cfu per ml saliva. S. mutans was most frequently isolated and was found in 114 persons (88%) alone or in combination with S. sobrinus. S. sobrinus was detected in 33 persons (25%), who also showed significantly higher salivary numbers of both mutans streptococci and lactobacilli than persons from whom S. sobrinus was not isolated. The S. sobrinus carriers also had significantly lower stimulated saliva secretion rates than the non-carriers. 95% of the subjects had detectable levels of lactobacilli in saliva with 35% having greater than 10(5) cfu per ml saliva. When the subjects were divided into classes according to the number of intermaxillary contacts, i.e. the Eichner classification, the distribution of subjects with high and low salivary counts of cariogenic bacteria varied. Thus fewer subjects belonging to Eichner class A showed higher salivary numbers of mutans streptococci (14% had greater than 10(6) cfu/ml) as well as lactobacilli (21% had greater than 10(5) cfu/ml) than, for example, subjects belonging to Eichner class B (26% had greater than 10(6) cfu/ml of mutans streptococci, 35% had greater than 10(5) cfu/ml of lactobacilli). Subjects who carried a removable denture(s) had significantly higher salivary numbers of both mutans streptococci and lactobacilli than subjects without removable dentures.

Aged↗
PubMed1990

[Miller-Dieker syndrome (type I lissencephaly) with specific EEG changes].

We present the case report of a girl with a subtype of Lissencephaly syndrome, type I, "Miller-Dieker syndrome", pointing out the specific EEG features in infancy and early childhood. The following pathognomonic EEG manifestations may confirm the diagnosis of an lissencephalic syndrome: abnormally fast background activity of an extraordinary high voltage increasing with age, missing topographic structuring, no reactivity to sleep or medication, unusually high-voltaged sharp-slow-wave complexes.

Agenesis of Corpus Callosum↗