Natural history and spontaneous prognosis of cerebral arteriovenous malformations

Eight large series of patients presenting with untreated cerebral arterio-venous malformations (A.V.M.) were reviewed. Data were gathered on 1134 patients who were followed for 20 years or more. The risk of rupture and the rate of other complications were estimated, in relation with other factors like age of patient, size of A.V.M., or hemodynamic stresses. The prevalence of A.V.M. at autopsy is 14 per 10,000 population. Fifty percent of A.V.M.s remain asymptomatic during the whole patient's life. The risk of hemorrhage from rupture of an A.V.M. is 2% per year and per patient. Hemorrhage is more frequent from small-sized A.V.M.s, mostly under certain hemodynamic factors. The risk of hemorrhage is also higher in children between 5 and 10 years of age, and in women to the end of pregnancy. The incidence of seizures and neurological impairment is approximately 1% per year and per patient, and these symptoms mostly occur in elder patients with large A.V.M.s. If the A.V.M. has not been revealed by hemorrhage, the risk of rupture is 1% per year and per patient. The incidence of complications from fortuitously diagnosed A.V.M.s seems very low, and even nil in some series. The risks of therapeutic procedures could not be determined, but in some A.V.M.s, the association of different therapeutic means seems mor advisable than isolated therapy. The analysis of natural history of A.V.M.s is desirable to provide a better information to the patient, and to define the limits of therapeutic indications.     

The advanced display of behavioral reactions in sensory deprived rat pups

Bilateral section of nervus medianus was made in Wistar rat pups on 13, 14, 15 or 16-th days of life. Developmental analysis of motor abilities, locomotor and exploration activities during 10-30 days of life revealed three groups of facts. 1. Partial deafferentation of forelimbs don't influence on some types of behavior. 2. Some motor abilities hindered in rat pups with section of nervus medianus. 3. Partial deafferentation of forelimb gives rise to the faster appearance of the new types of behavior. The developmental analysis allowed to suggest that faster appearance of certain behavior reactions after deafferentation of the forelimbs is a result of actualization of latent sensory inputs including in the organization of these types of behavior but it is not connected with changing of velocity of morphological maturation.     

Toxic metabolites of Amanita pantherina, A. cothurnata, A. muscaria and other Amanita species

Forty-seven specimens representing 35 species or varieties of Amanita were examined for the presence of ibotenic acid, muscimol, stizolobic acid, stizolobinic acid, aminohexadienoic acid and chlorocrotylglycine. In addition, crude extracts of A. muscaria were examined chromatographically for the presence of methyltetrahydrocarboline carboxylic acid (MTC). Ibotenic acid and muscimol were found in clearly detectable concentrations in extracts of A. cothurnata, all specimens of A. muscaria, all specimens of A. pantherina and in lower concentrations in A. gemmata. Stizolobic acid and stizobinic acid were found in detectable concentrations in one variety of A. muscaria, in all specimens of A. pantherina and in trace levels after additional purification of the extracts in A. gemmata and in the remaining specimens of A. muscaria. Aminohexadienoic acid and chlorocrotylglycine were detected only in crude extracts of A. smithiana. MTC could not be detected in crude extracts of A. muscaria. Crystalline ibotenic acid (820 mg) was isolated from 17 kg of a specimen of A. pantherina collected in western Washington State.     

Nature of the curves of the cranial vault and their relationship with various brain structures

A radiometric investigation for various angles of two dry craniums and of the encephalographic or cerebral arteriographic pictures of 250 subjects has revealed the following facts: The architectural lines of the dome of the skull found by orthogonal projection of the profile, from the front, and in vertical projection, are hyperbolic spirals starting from the base of the skull and converging on the sphenoid. These lines join up in the parietal region forming a hyperbole. The frontal spiral is a simple hyperbolic spiral. The temporal spiral is of the lituus type. The axes of these lines converge in a frontal plane on the epiphysis. The axis of the parietal hyperbole on a projection of the profile passes through the epiphysis and is followed by the parietal artery. Central cranio-encephalic formations follow the same spiral path. The contour of the upper edge of the cerebellum is a lituus spiral. The outline of the lower part of the cerebellum is a simple hyperbolic spiral. The right side of the polar origins of a spiral plotted in the plane of the insula coincides with the right side of the opercula. It can always be plotted, in theory, and forms an angle of 22 degrees 30' with the right side of the median frontal spiral. It cuts the axis of the parietal hyperbole at the apex of the insular triange. The bissector of the angle formed by the two right sides of the polar origins bissects the axis of the parietal hyperbole at a point corresponding to the epiphysis. The temporal hyperbolic lituus spiral has its focal point under the anterior, clinoid, at the junction of the segments CII and CIII of the carotid siphon the curve of which follows the convolutions of the temporal spiral. The right side of the polar origins of this curve indicates the mean direction of the posterior cerebral. The contours of the corpus callosum are homothetic with those of the dome of the skull as far as the axis of the parietal hyperbole. The frontal and parietal curves converge according to four types in the main Pacchionian granulations. The sections of the frontal spiral are often marked by bone abnormalities on the internal table. This analytic test is invariably valid whatever the constants of the spirals or the eccentricities of the hyperboles. Combinations between spirals with different constants and hyperboles of various eccentricities amount to very many types which call for separate study.     

Chemical mixtures in the workplace. Research and practice

1. Exposures to mixtures of chemicals in occupational settings and in the environment are of increasing concern. No single approach is appropriate for determining the risk associated with exposure to chemical mixtures. 2. The effects of coexposure of chemicals can occur in different stages of metabolism, including uptake, elimination, biotransformation, and binding. 3. Solvents represent the most widespread use of multicomponent mixtures in industry today. Solvents have the ability to inhibit the metabolism of other chemicals. 4. Lifestyle factors such as exercise, alcohol use, smoking, and the use of medications can affect the uptake and metabolism of chemicals. The effects of these factors are of particular significance in interpreting the results of biological monitoring of exposed workers.     

The mechanism of the excitatory action of catecholamines and histamine on the smooth muscle of guinea-pig ureter

1. The ionic mechanism of the excitatory action of catecholamines and histamine on the smooth muscle cells of guinea-pig ureter was studied with the double sucrose-gap method. 2. In normal conditions adrenaline and noradrenaline in a concentration of 10(-5) g/ml., and histamine in a concentration of 10(-6) g/ml., prolonged the duration of the plateau of the action potential and increased the amplitude and duration of the phasic contraction. Sometimes these changes were accompanied by a slight depolarization of the muscle membrane and by a small increase (with noradrenaline) or decrease (with histamine) of the membrane resistance. The amplitude and duration of the fast spike component of the action potential were not changed. 3. Isoprenaline in a concentration of 10(-5) g/ml. either caused no change or it decreased the duration of the plateau, reduced the amplitude of contractions and reduced excitability. 4. Tetraethyl ammonium (TEA; 5 mM), which blocks the delayed outward K current, did not prevent the increase in the duration of the plateau nor the increase of the amplitude and duration of the contractions by noradrenaline and histamine. 5. In Na-free or in K-free solution or in the presence of ouabain, i.e. in conditions in which the Na-gradient across the membrane was reduced, noradrenaline and histamine were unable to increase the duration of the plateau and the amplitude and duration of the contraction. 6. In the presence of Mn2+ (2 mM) which suppressed the spike component of tha action potential and the phasic contraction, theeffects of noradrenaline and histamine were almost abolished. 7. The results suggest a dual ionic mechanism of the alpha-action of catecholamines and of the action of histamine on the smooth muscle of ureter: (1) these drugs affect the passive ionic permeability of the membrane in a manner that results in depolarization; (2) they specifically activate the potential-dependent conductance of the slow Na channels, thereby increasing the plateau duration. The increased amplitude and duration of the contraction is the result of their primary effect on the plateau of the action potential.     

Clinical and bacteriological studies on panipenem/betamipron in pediatrics. Kanagawa Research Group for Infectious Diseases of Children

Following its introduction into the market, PAPM/BP (panipenem/betamipron) was clinically studied in 188 evaluable cases out of 207 cases primarily of respiratory infectious diseases treated at the pediatric departments of 15 hospitals. In the clinical evaluation, the drug proved effective in three of three cases of sepsis; three of three cases of suppurative meningitis; nine of ten cases of laryngopharyngitis, six of seven cases of tonsillitis, 56 of 63 cases of acute bronchitis, 90 of 98 cases of pneumonia, and one of one case of phyothorax, all of which are respiratory infectious diseases; one of one case of secondary infection of a chronic respiratory disease; and two of two cases of lymphadenitis, which is a disease of the soft dermal structure. The overall efficacy rate was 91.0% (171/188 cases). In the bacteriological study, Gram-positive bacteria were eliminated in five of five strains of S. aureus, 30 of 31 strains of S. pneumoniae (96.8%), and three of three strains of S. pyogenes. Gramnegative bacteria were eliminated in 15 of 17 strains of H. influenzae (88.2%), three of four strains of M. catarrhalis, and two of two strains of K. pneumoniae. The overall elimination rate was 92.1% (70/76 strains). In the 23 strains of S. pneumoniae that were examined, penicillin-resistant strains accounted for 56.5%, showing an elimination rate of 100%. No serious adverse effects were observed, and the incidence of adverse effects was 1.45%. As for abnormalities in laboratory tests, levels of GOT and GPT increased in eight cases (3.88%), LDH increased in one case (0.48%), and neutropenia occurred in one case (0.51%). These results suggest that PAMP/BP could be considered the first choice in the treatment of infectious diseases in pediatrics, due to its effectiveness and high level of safety.     

TiC-WC粒度和微观结构与WC粒度和微观结构的关系及其对硬质合金性能的影响

研究了WC粒度和微观结构对TiC-WC固溶体粒度和微观结构及合金性能的影响。结果表明,TiC-WC固溶体粒度随WC粒度的增粗而增大,其亚晶尺寸随WC亚晶尺寸的增大而减小,而微观应变则随WC微观应变的减小而增大。TiC-WC固溶体和合金之间的微观结构存在着良好的依赖关系。由大的亚晶尺寸和低微观应变的TiC-WC固溶体制取的合金,其抗弯强度和冲击韧性较好。     

Distribution of the interstitial cells of Cajal in the human anorectum

The interstitial cells of Cajal are proposed to have a role in the control of gut motility. The aim of this study was to establish the distribution of interstitial cells of Cajal in the wall of the normal human anorectum. Interstitial cells of Cajal express the proto-oncogene c-kit. Interstitial cells of Cajal were identified in the colon by immunohistochemical staining, using a rabbit polyclonal anti-c-kit antibody. Anorectal tissue was obtained at surgical resection for carcinoma of the colorectum. Density of interstitial cells of Cajal was graded. Statistical analysis was performed using chi2 tests. In the longitudinal and circular muscle layers of the rectum interstitial cells of Cajal were seen in the bulk of the muscle layer. In the intermuscular plane interstitial cells of Cajal encased the myenteric plexus. Interstitial cells of Cajal were found at the inner margin of the circular muscle and in association with neural elements of the submuscular plexus. Within the internal anal sphincter interstitial cells of Cajal were infrequently scattered among the muscle fibres. The density of interstitial cells of Cajal in the internal anal sphincter was significantly lower than that observed in the circular muscle layer of the rectum (P = 0.014). In conclusion, interstitial cells of Cajal are evenly distributed in the layers of the muscularis propria of the rectum, but have a lower density in the internal anal sphincter.     

Cortistatin increase of a potassium conductance in rat locus coeruleus in vitro

1. In this study we examined the effects of cortistatin, a putative endogenous ligand for somatostatin (SRIF) receptors, on the membrane properties of rat locus coeruleus (LC) neurones in vitro, by use of intracellular and whole cell patch clamp recording. We have compared the actions of cortistatin with those of SRIF and the SRIF analogue D-Phe-Cys-Tyr-D-Trp-Orn-Thr-Pen-Thr-NH2 (CTOP). 2. When LC neurones were voltage clamped to -60 mV, application of cortistatin caused an outward current in all cells examined (n = 44), with a pEC50 of 6.62. SRIF also caused an outward current in all cells examined (n = 43), with a pEC50 of 6.93. 3. The outward currents caused by cortistatin in 2.5 mM extracellular K+ reversed polarity at -106 mV, very close to the predicted K+ reversal potential of -105 mV. Increasing extracellular K+ to 10.5 mM resulted in a shift of the reversal potential of +38 mV, a shift consistent with a K+ conductance. The conductance activated by cortistatin showed mild inward rectification. 4. Continuous application of a high concentration of SRIF (1 microM) resulted in a decrease of the outward current to a steady level of 49% of the maximum response, with a t1/2 of 131 s. Application of a high concentration of cortistatin (3 microM) during the desensitized portion of the SRIF response did not result in any further outward current. Continuous application of a high concentration of cortistatin (10 microM) resulted in a decrease of the outward current to a steady level of 42% of the maximum response with a t1/2 of 114 s. Application of a high concentration of SRIF (3 microM) during the desensitized portion of the cortistatin response produced only a small outward current. 5. Continuous application of cortistatin (3 microM) also resulted in a decrease of the outward current (by 43%, t1/2 of 136 s) and application of a high concentration of CTOP (10 microM) during the desensitized portion of the cortistatin response did not produce any outward current. Continuous application of a high concentration of CTOP (10 microM) resulted in a decrease of the outward current to a steady level of 70% of the maximum response with a t1/2 of 143 s. Application of a high concentration of cortistatin (3 microM) during the desensitized portion of the CTOP response did not result in any further outward current. 6. The actions of cortistatin (300 nM-10 microM) were not affected by the opioid antagonist naloxone (10 microM). Application of met-enkephalin during the desensitized portion of the response to a high concentration of cortistatin (3 microM) produced an outward current similar to that produced by metenkephalin application alone. 7. Thus cortistatin efficaciously activates an inwardly rectifying K+ conductance in LC neurones. These actions appear to be mediated by a population of SRIF receptors, at which CTOP is also an agonist. Cortistatin does not appear to be a ligand for mu-opioid receptors in rat LC neurons.     

Results of bone scintigraphy in horses used for show jumping, hunting, or eventing: 141 cases (1988-1994)

OBJECTIVE: To determine anatomic patterns and clinical importance of increased radiopharmaceutical uptake in bones of horses used for show jumping, hunting, and eventing. DESIGN: Retrospective study. ANIMALS: 141 horses evaluated because of lameness. PROCEDURE: Medical records were reviewed, and information on results of physical examination, radiography, and scintigraphy were obtained. Scintigrams were evaluated to identify areas of increased radio-pharmaceutical uptake. RESULTS: 834 areas of increased radiopharmaceutical uptake were identified. Scintigraphy of the vertebral column was performed in 78 horses, and 50 had areas of increased radiopharmaceutical uptake involving the spinous processes. Scintigraphy of the proximal phalanx of the forelimb was performed in 88 horses. Similarly, scintigraphy of the proximal phalanx of the hind limb was performed in 99 horses, and scintigrams of 374 proximal phalanges were available for review. One hundred fifty-five scintigrams had areas of increased radiopharmaceutical uptake. Scintigraphy of the tarsal joint was performed in 99 horses, and scintigrams of 198 joints were available for review. Eighty-five had areas of increased radiopharmaceutical uptake. Overall, 214 of 834 areas of increased radiopharmaceutical uptake were definitively associated with lameness. CLINICAL IMPLICATIONS: Results of this study suggest that jumping creates unique stresses on the bones of horses. The distinctive patterns of increased radiopharmaceutical uptake identified in this study suggest that horses used for jumping may have a predilection to develop orthopedic disease at specific sites distinct from those in racehorses.     

Experimental and clinical validation of using enterosorption in mechanical jaundice

Experiments in 119 rats with the model of mechanical jaundice have shown the efficiency of enterosorption with polyphepan. The development of the pathological process was found to improve, lethality of the experimental animals to decrease. Favourable changes of the laboratory indices characteristic of endotoxemia were noted. The mechanism of medical action of enterosorption is realized by means of intensification of transfer of masses of metabolites and toxins through the intestine wall and their excretion through the gastrointestinal tract. One of important mechanisms of the medical action of enterosorption is the stimulation of intestinal peristalsis which is confirmed by data of the dynamics of bioelectrical activity. Enterosorption performed in 60 patients with mechanical jaundice was followed by a more rapid improvement of the general state, decrease of the indices characteristic of endotoxicosis as compared with 60 patients of the control group. The frequency of postoperative complications and lethality were reliably lower.     

Actions of drugs affecting the cough reflex

BACKGROUND AND AIM: Authors evaluated the part of some receptor systems in the antitussive activity of drugs. METHOD: The cough was induced by mechanical stimulation of the airways. Unanesthetized cats were used in this study. RESULTS: They followed: 1. statistically highly significant decrease of cough parameters after administration the drugs influencing the different types of opiate receptors--tramadol, tilidine, pentazocine, codeine and butorphanol. Every of these drugs were administered in a dose 10 mg/kg b.w. intraperitoneally, 2. the antitussive activity of codeine was decreased by pretreatment with naloxone only in part, 3. selective antagonist 5-HT2 receptors ketanserine (1 mg/kg b.w.) decreased antitussive effect of codeine by 10% and effect of tramadol by 20%, 4. the ability of codeine to reduce the cough parameters was unchanged after pretreatment with haloperidol (0.1 mg/kg b.w.), 5. whereas the pretreatment with reserpine decreased the cough-suppressing effect of codeine, 6. the application of gabaergic agent gabalid leads to the highly significant decrease the cough parameters. Results of these experiments showed that gaba-ergic mechanism might be involved in the mechanism of action of narcotic antitussives agents, 7. we showed, that inhibition of glutaminergic synaptic transmissions afferent impulses from cough receptors with dextromethorphan leads to suppressing cough reflex in cats. CONCLUSIONS: Antitussive activity of agents is not only mediated by means of mí opiate receptors. The results suggest, that gabaergic, serotoninergic systems and activity of NMDA receptors play an important role in the mechanism of action of antitussive drugs. Decrease in levels of brain monoamines modifies the cough-depressant effect of codeine. (Fig. 7, Ref. 23.)     

Delayed healing of chronic gastric ulcer after Helicobacter pylori infection in mice

It has been suggested that there is a close relationship between Helicobacter pylori and the onset or recurrence of gastroduodenal disease. The aim of this study was to examine the effect of H. pylori on the healing of chronic gastric ulcers induced in mice. H. pylori administered to nude mice delayed the healing of experimental acetic acid-induced gastric ulcers. Histological examination showed the occurrence of high densities of H. pylori on the surface of epithelial cells and in the ulcerated area. Repeated administration of amoxicillin (10 mgkg(-1) daily for 5 days) eradicated H. pylori and increased the rate of healing of gastric ulcers in H. pylori-infected mice, but metronidazole, which also eradicated the organisms, did not significantly affect the rate of healing. In conclusion, H. pylori-infection delayed the healing of gastric ulcers induced by the serosal application of acetic acid in mice, possibly by aggravation or prolongation of the mucosal inflammation. Amoxicillin eradicated H. pylori and promoted gastric ulcer healing in mice infected with H. pylori.     

The scientific development in dermatology in Germany in relation to the emigration of Jewish dermatologists during national socialism

The anti-semitic laws let to the persecution of the Jews in Germany during the time of National Socialism. About 600 Jewish dermatologists had to suffer from the prohibition of their profession. 63% of them left Germany. The emigrants mainly preferred to move out to the U.S. The policy of coordination and elimination of the National Socialists led to the reappointment of dermatological chairs in universities. The National Socialists also forced the change in the boards of dermatological societies and the change of the editorial boards of dermatological journals. All papers of the three leading dermatological journals were analysed for the evaluation of the development of science. The assessment included the number of articles, the origin of the authors and the contents of articles (research, clinics, diagnostic, therapy). From 1933 to 1945 the number of papers per year decreased consequently, especially during the Second World War. During the whole time the number of German authors increased and the number of abroad living authors decreased. There was a very good and interesting international exchange of information in the journal "Archiv für Dermatologie und Syphilis". The activity reduced clearly after the beginning of the Second World War in 1939. The analysis of contents resulted in a reduction of basis science research and an orientation to the clinical research. Papers about therapeutical possibilities were always published. The emigration of Jewish dermatologists led to a continuous reduction of scientific activities and to an extensive international isolation.     

Early events in the histo- and cytogenesis of the vertebrate CNS

Development of the vertebrate, viewed on the cellular level, proceeds by sequential steps in which potencies of progenitor cells become progressively and irreversibly restricted. This is known as progression of the major differentiation. Cytogenesis of the CNS may be regarded as one typical example. The period of cytogenesis in the CNS is divided into three consecutive stages. In stage I, the wall of the neural tube is composed solely of matrix cells. In stage II, i.e., the stage of neuronogenesis, some of the daughter matrix cells are determined at the early G1 phase to be differentiated into neuroblasts. The specificity of individual neurons appears to be irreversibly determined at the time of birth of the neuroblasts, as a function of time-and-place of their production. The individual matrix cells that have existed at the very beginning of neurogenesis give birth to a series of progressively different types of neurons in stage II as the major differentiation proceeds. Finally, matrix cells cease to produce neurons. This is the end of stage II. Thereafter, only non-neuronal cells, namely neuroglia and ependymal cells, are produced. This is stage III or the stage of neuroglia production. The sequential nature of the differentiative behavior of matrix cells can be explained by the hypothesis of progressive gene inactivations that accumulate in genomes of matrix cells during development. Different types of neurons are produced from matrix cells at different states of the "major differentiation".(ABSTRACT TRUNCATED AT 250 WORDS)     

[Leona E. Tyler].

Leona E. Tyler, one of the nation's leading authorities on individual differences and counseling, has been elected as the 1971-1972 President-elect of the American Psychological Association. Dr. Tyler will assume her new position in December 1972 when Dr. Anne Anastasi of Fordham University becomes APA President. Dr. Tyler has served as President of the Western Psychological Association and of the Oregon Psychological Association. She has also been President of APA's Division of Counseling Psychology. She is a member of the American Association for the Advancement of Science, Sigma Xi, the Society for Research in Child Development, and has been awarded a Diploma in Counseling by the American Board of Professional Psychology. She earned her BS, MS, and PhD degrees at the University of Minnesota, and has served on the faculties of the University of Oregon, the University of California at Berkeley, and the University of Amsterdam. Dr. Tyler is the fourth woman to be chosen president of the APA. Previous woman presidents include the current President-elect Anne Anastasi, Margaret F. Washburn of Vassar College in 1921, and Mary W. Calkins of Wellesley in 1905. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The demonstration of heritable lethal mutations in the progeny of x-ray-irradiated CHO cells by micronucleus count in clone cells

PURPOSE: Low doses of ionizing radiation reduce the growth rates of clones following irradiation of the progenitor cells. Such reductions of clone growth have been proven by means of measurements of clone size distributions. The medians of such distributions can be used to quantify the radiation damage. Prolongations of generation times and cell death as result of heritable lethal mutations have been discussed as causes for the reduction of clone growth. MATERIAL AND METHODS: The cell number of a clone of hypotetraploid CHO-cells was compared to the frequency of micronucleated binucleated cells in the same clone using the cytokinesis-block-micronucleus method. The dose dependent reduction of clone sizes is measured by the difference of the medians (after log transformation) of the clone size distributions. RESULTS: At cytochalasin-B concentrations of 1 microgram/ml and after an incubation time of 16 h a yield of binucleated cells of about 50% was obtained. Median clone size differences as a measure of clonal radiation damage increased linearly with incubation times of 76, 100, 124, and 240 h following irradiation with 3, 5, 7, and 12 Gy. The frequency of binucleated clone cells with micronuclei strongly increased with decreasing clone size by a factor up to 20 following irradiation with 3, 5, and 7 Gy. The frequency of micronucleated binucleated clone cells was found to be independent of incubation time after irradiation. CONCLUSION: Radiation induced clone size reductions result from cell losses caused by intraclonal expression of micronuclei which have its origin in heritable lethal mutations. Measurements of clone size distributions can be done automatically. They can serve as predictive test for determination of median cell loss rates of surviving cell clones.     

Streptococcus faecalis and Streptococcus faecium in infected dental root canals at filling and their susceptibility to azidocillin and some comparable antibiotics

The study was performed on 612 routine cultures of material obtained from root canals of teeth at the time of filling (r-cultures) by students at the Department of Endodontics during a continuous period of one year. Twenty-nine isolates from 27 (29.3%) of the 92 positive cultures filled the criteria of enterococci (Sherman, 1937) and had demonstrable group D-antigen. With a set of tests these isolates were identified as follows: Strep. faecalis subsp. faecalis (10), Strep. faecalis subsp. zymogenes (3), Strep. faecalis subsp. liquefaciens (8), atypical variants of Strep. faecalis (6), Strep. faecium var. faecium (1) and Strep. faecium var. durans (1). Five tests in the present study clearly differentiated Strep. faecalis from Strep. faecium i.e. fermentation of sorbitol, glycerol (anaerobic) and melezitose, tolerance to potassium tellurite (0.1%) (positive for Strep. faecalis) and production of hydrogen peroxide (positive for Strep. faecium). In the inocula 10(3) or more colony forming units of enterococci were found more often of other identified microorganisms. This means that enterococci are of special interest in studies on the influence of infection at the time of filling of root canals on the prognosis of root canal therapy. The isolates were also tested for susceptibility to azidocillin, ampicillin, penicillin-G, penicillin-V and erythromycin with the paper disc method. All the isolates were susceptible to azidocillin and ampicillin (sensitivity group I), while the majority of the isolates showed a lower susceptibility to the other three antibiotics (sensitivity group II). The significance of these findings in the choice of prophylactic antibiotic to prevent bacterial endocarditis in patients with a history of rheumatic or congenital heart disease are discussed, when bacteremia from dental procedures may be expected.