Atypical dermoid cyst of the corpus callosum: a case report

BACKGROUND

Intracranial dermoid cysts (DCs) represent an infrequent subset of congenital ectodermal inclusion cysts predominantly observed near the midline structures. In spite of their benign nature, they can cause clinical manifestations, necessitating surgical removal as the main therapeutic measure.

CASE REPORT

We present here an extremely rare case characterized by a radiologically atypical dermoid cyst located within the corpus callosum, an extremely rare location for such tumors. Successful surgical excision resulted in good clinical outcomes.

CONCLUSIONS

This paper underscores the importance of a timely, proper radiological diagnostic process, which sees magnetic resonance imaging (MRI) as the main step, as well as the fact that interpretation of MRI data can sometimes be challenging, as it was in the patient of this report.

Registry-derived stage (RD-Stage) for capturing cancer stage at diagnosis for endometrial cancer

BACKGROUND

Capture of cancer stage at diagnosis is important yet poorly reported by health services to population-based cancer registries. In this paper we describe current completeness of stage information for endometrial cancer available in Australian cancer registries; and develop and validate a set of rules to enable cancer registry medical coders to calculate stage using data available to them (registry-derived stage or 'RD-Stage').

METHODOLOGY

Rules for deriving RD-stage (Endometrial carcinoma) were developed using the American Joint Commission on Cancer (AJCC) TNM (tumour, nodes, metastasis) Staging System (8th Edition). An expert working group comprising cancer specialists responsible for delivering cancer care, epidemiologists and medical coders reviewed and endorsed the rules. Baseline completeness of data fields required to calculate RD-Stage, and calculation of the proportion of cases for whom an RD stage could be assigned, was assessed across each Australian jurisdiction. RD-Stage (Endometrial cancer) was calculated by Victorian Cancer Registry (VCR) medical coders and compared with clinical stage recorded by the patient's treating clinician and captured in the National Gynae-Oncology Registry (NGOR).

RESULTS

The necessary data completeness level for calculating RD-Stage (Endometrial carcinoma) across various Australian jurisdictions varied from 0 to 89%. Three jurisdictions captured degree of spread of cancer, rendering RD-Stage unable to be calculated. RD-Stage (Endometrial carcinoma) could not be derived for 64/485 (13%) cases and was not captured for 44/485 (9%) cases in NGOR. At stage category level (I, II, III, IV), there was concordance between RD-Stage and NGOR captured stage in 393/410 (96%) of cases (95.8%, Kendall's coefficient = 0.95).

CONCLUSION

A lack of consistency in data captured by, and data sources reporting to, population-based cancer registries meant that it was not possible to provide national endometrial carcinoma stage data at diagnosis. In a sample of Victorian cases, where surgical pathology was available, there was very good concordance between RD-Stage (Endometrial carcinoma) and clinician-recorded stage data available from NGOR. RD-Stage offers promise in capturing endometrial cancer stage at diagnosis for population epidemiological purposes when it is not provided by health services, but requires more extensive validation.

AB0683 Polyneuropathy impact on disability in systemic sclerosis patients

Background

Systemic sclerosis (SSc) is one of the most severe autoimmune rheumatic diseases with high morbidity and mortality rates 1. Peripheral neuropathy in SSc is reported with a broad prevalence variable between 0.01% to 28% 2. Developed in 1978, the Health Assessment Questionnaire Disability Index (HAQ-DI) for rheumatoid arthritis, nowadays is widely used to measure functional status in patients with SSc as well, but data are lacking in SSc patients with polyneuropathy (PN) 3.

Objectives

To determinate the impact of PN on disability in SSc patients.

Methods

This was cross-section study in patients with SSc. Study was conducted in two University hospitals in Latvia for adults. Study included patients diagnosed with SSc that met the ACR / EULAR 2013 accepted classification criteria and have been consulted by rheumatologists between 1st January 2016 and 31st July 2021. Patients who agreed to comply in the study were evaluated by one rheumatologist and were surveyed and clinically evaluated according to The European Scleroderma Trials and Research group accepted domains. Disease duration was defined as time from first non-Raynaud SSc symptom to date of examination. SSc subtype was evaluated in each patient by clinical presentation that included modified Rodnan score (mRSS) as well: limited cutaneous systemic sclerosis (lcSSc) with skin thickening distal to the elbow/knee and diffuse cutaneous systemic sclerosis (dcSSc) with skin thickening proximal to the elbow/knee. For neuropathic pain assessment, the Neuropathic Pain Diagnostic Questionnaire (DN4) was used. Peripheral neuropathy symptoms were assessed using total neuropathy score (TNS). Peripheral nerve conduction study (NCS) and quantitative sensory testing (QST) was used to detect PN.

Functioning and disability were assessed using HAQ-DI. All patients completed the HAQ-DI form in the same day as they were evaluated, filling the form in native language.

Results

From 109 acknowledged patients, 67 were able to come for a visit, 54 females, 13 males. Mean age for females 62.54±12.02 years, for males 58.69±14.50 years.

After assessment by rheumatologist, 50 were classified as lcSSc, 17 were classified as dcSSc. The overall ratio of lcSSC and dcSSc was 50:17, in females 41:13, in males 9:4. Disease duration ranges from 1 to 39 years (mean 15.49±10.18), 16.61±10.47 years for females, 10.85±7.55 years for males. Large fiber PN was diagnosed in 47.8% of subjects by NCS (n=32/67) and small fiber PN in 40.3% of subjects by QST (n=27/67), while 11.9% had neither (n=8/67). Mean HAQ-DI score was 1.22. There was no statistically significant difference in HAQ-DI score between males (1.08±0.89) and females (1.26±1.01), (p=0.13). As well there was no difference between HAQ-DI score in patients with large fiber/small fiber neuropathy and without neuropathy symptoms (p=0.6817). But we found that neuropathy symptoms (assessed by TNS) have moderately strong and statistically significant correlation with HAQ-DI (r=0.39, p=0.0012). As well we found moderately strong correlation between HAQ-DI and neuropathic pain (assessed by DN4) (r=0.45, p=0.00015).

Conclusion

PN is more common complication in SSc that was previously reported, with significant impact on QoL.

References

[1]Sobolewski P, Maślińska M, Wieczorek M, et al. Systemic sclerosis - multidisciplinary disease: clinical features and treatment. Reumatologia. 2019;57(4):221-233. doi:10.5114/reum.2019.87619

[2]Raja J, Balaikerisnan T, Ramanaidu LP, Goh KJ. Large fiber peripheral neuropathy in systemic sclerosis: A prospective study using clinical and electrophysiological definition. Int J Rheum Dis. 2021 Mar;24(3):347-354. doi: 10.1111/1756-185X.14042. Epub 2021 Jan 11. PMID: 33432774.

[3]Allanore, Y., Bozzi, S., Terlinden, A. et al. Health Assessment Questionnaire-Disability Index (HAQ-DI) use in modelling disease progression in diffuse cutaneous systemic sclerosis: an analysis from the EUSTAR database. Arthritis Res Ther 22, 257 (2020). https://doi.org/10.1186/s13075-020-02329-2

Disclosure of Interests

None declared

PTH Immunoassay Interference Due to Human Anti-Mouse Antibodies in a Subject With Obesity With Normal Parathyroid Function

CONTEXT

Immunoassay interference has been most often found with prolactin measurement. However, only few data exist on immunoassay interference for other hormones.

CASE DESCRIPTION

A 36-year-old woman with obesity (body mass index, 31 kg/m2) had regularly attended our endocrine unit for type 2 diabetes therapy. When she was included as a control subject in a study for obesity management, detailed laboratory testing was performed, including PTH. In the absence of clinical symptoms, she presented with normal calcium, phosphate, and vitamin D levels. However, the PTH levels were >5000 ng/L. These results were obtained using the Roche Elecsys electrochemiluminescence assay. Repeated measurements with this assay (mouse antibody) led to the same findings. However, using an Euroimmun assay (goat antibody), the exact PTH values were measured at 18.0 ng/L. After pretreatment with a heterophilic antibody blocking reagent, the results of the Roche assay had decreased to a normal level. This phenomenon was explained by the detection of human anti-mouse antibodies in the proband's serum.

CONCLUSIONS

In cases of prolactin immunoassay interference, endogenous antibodies will bind to the hormone in vivo, resulting in complexes of a high molecular weight that are less efficiently cleared by the kidneys and, thus, accumulate in the blood. In contrast, the PTH values >5000 ng/L detected in our subject most likely had resulted from the specific interference of the human anti-mouse antibodies present in the proband's serum with the assay antibody, resulting in artificial stimulation of the Roche assay detection system ex vivo.

Trabeculectomy training in England: are we safe at training? Two year surgical outcomes

OBJECTIVES

To define the safety profile of trainee trabeculectomy surgery in the United Kingdom. Surgical exposure for trainees in England is limited due to service requirements, the European working time directive constraints and increasing sub-specialisation of glaucoma surgery. Limited knowledge exists on the outcomes of supervised glaucoma surgery. The aim is to determine the safety of supervised trabeculectomy surgery performed by trainee ophthalmologists.

METHODS

Retrospective case note review of all patients that had trabeculectomy surgery with MMC by consultant and trainee surgeons across multiple UK centres. All eyes have 2-year follow up. Success was determined using WGA guidelines. Two-tailed p values were obtained using Fisher's exact test to ascertain statistical significance between groups.

MAIN OUTCOME MEASURES

intraocular pressure, visual acuity, success and failure rates.

RESULTS

324 eyes were reviewed. 211 (66.4%) cases were performed by glaucoma consultants, 107(33.6%) by trainee ophthalmologists. The majority of eyes in each group were undergoing surgery for POAG. Post-operative IOP control showed no significant difference between consultant and trainee groups at year 1 and year 2. Success rates showed no significant difference between consultant and trainee cases. Failure rates at year 1 showed a significant difference between the two groups. No significant difference was seen at year 2. The trainee group had significantly more complications, when compared with the consultant group. Snellen visual acuity loss was not statistically significant between the two groups at the 2 year time point.

CONCLUSIONS

The outcomes of supervised trainee trabeculectomy compare favourably with consultant cases after 2 year follow up. Trainee cases had higher complication rates than consultant cases. Bleb leaks are a common complication of trainee cases, where closer supervision may be required. There is potential for surgical simulation to help increase the success of such cases. These findings may encourage trainee participation in glaucoma surgery.

[MICROSATELLITE INSTABILITY AND SURVIVAL IN PATIENTS WITH ENDOMETRIAL CANCER.]

Microsatellite-unstable genotype associated with deficiency mismach repaired enzymes leads to the accumulation of a series of mutations in the coding and regulatory regions of the genes having a role in carcinogenesis in endometrial cancer (ECs). The aim of this study was to investigate the correlation between the expression of four main mismach repaired enzyme (MLH-1, MSH-2, MSH-6 and PMS-2) with patients survival. ECs from 70 women (median of 63 years, range of 43-79 years) were assessed immunohistochemically for microsatellite instability (MSI). In our study we found that the presence of MSI, determined by the absence of immunohistochemically expression of at least one of the test four of the enzyme mismach repaired system is associated, not statistically significant, with longer survival (p = 0.558). In conclusion we may state that the immunohistochemical analysis who indicates MSI in biopsy tissue is a one step forward for the determination of survival and progression of endometrial carcinoma.

Radiological impact of surface water and sediment near uranium mining sites

The aim of this study is to assess the radiological impact of surface water and sediment around uranium mining sites 20 years after their closing. The areas under observations are 31 former classical underground uranium mining and exploratory sites in Bulgaria, named as objects. The extraction and processing of uranium ores in the Republic of Bulgaria were ended in 1992. To assess the radiological impact of radionuclides field expeditions were performed to sample water and bottom sediment. The migration of uranium through surface water was examined as one of the major pathways for contamination spread. The range of uranium concentration in water flowing from the mining sites was from 0.012 to 6.8 mgU l(-1) with a geometric mean of 0.192 mgU l(-1). The uranium concentrations in water downstream the mining sites were approximately 3 times higher than the background value (upstream). The concentrations of Unat, (226)Ra, (210)Pb, and (232)Th in the sediment of downstream river were higher than those upstream by 3.4, 2.6, 2, and 1.7 times, respectively. The distribution coefficient of uranium reflects its high mobility in most of the sites. In order to evaluate the impact on people as well as site prioritization for more detailed assessment and water management, screening dose assessments were done.

[Molecular based targets and endometrial cancer]

In recent years, increasing attention has been paid to the rate of spread of endometrial carcinoma, especially in the postmenopausal period. Along with routine diagnostic methods, giving information on the location and progression of the disease, there are some morphological methods determining very accurately the correlations in the development of this type of cancer and his prognosis. Moreover--in recent years, the accumulated information about the molecular profile of this type of cancer made it possible to implement a number of new drugs against the so-called molecular therapy -'targets' in the neoplastic process. Significant proportion of cases show response rates, it is more hope in the development of more successful formulas and target -based therapy. In this review, we present and discuss the role of certain molecular markers as potential indicators of prognosis and development, as well as determining the target treatment of endometrial carcinoma.

[MICROSATELLITE INSTABILITY IN ENDOMETRIAL CANCER]

Microsatellite instability (MSI) is involved in the pathogenesis of about 30% of endometrial cancer cases. In accumulating data from the past few years MSI is shown to have both clinical and prognostic value. In the present work we are discussing the components and molecular mechanisms of functioning of the mismatch repair system (MMR). MSI is a hallmark of endometrial tumors with DNA MMR deficiency. We summarized the main pathways for accumulating mutations in coding and non-coding DNA sequences, which is a result of errors during replication of microsatellite tandem repeats. A few studies rising valuable conclusions about the correlation between MSI and endometrial cancer are revised.

Acute toxoplasmosis mimicking melanoma metastases: review of conditions causing false-positive results on (18)F-FDG PET/CT

Invasive malignant melanoma is the most common fatal form of skin cancer. Fluorine-18-fluorodeoxyglucose positron emission tomography-computed tomography demonstrates a very high sensitivity and specificity for the detection of melanoma metastases. Here, we report an unusual case of toxoplasma lymphadenitis in a male adult patient mimicking a malignant cervical lymphadenopathy. Toxoplasmosis is a zoonosis caused by the intracellular parasite Toxoplasma gondii, which is usually asymptomatic in immunocompetent hosts.

Campylobacteriosis and other bacterial gastrointestinal diseases in Sofia, Bulgaria for the period 1987 – 2008

Campylobacter is the most commonly reported enteric bacterial pathogen in humans. We still do not have any systematic data concerning campylobacteriosis in Bulgaria. For that reason, we present data of the thermophilic Campylobacter jejuni and Campylobacter coli in the aetiology of diarrhoeal diseases in Sofia, for the period from 1987 to 2008. The study included patients from 0 to over 65 years-old. A total of 51,607 faecal specimens were screened for Campylobacter. C. jejuni and C. coli were detected in 3.58% (1,847) of the strains, with the highest percentage in 1988 (7.5%) and the lowest in 2006 (0.3%). Campylobacteriosis occurred most frequently in the wet months of March, April, May and June, with 105, 102, 124 and 141 cases, respectively, and was rare in January with 25 cases. The most affected groups were children between 0 and 4 years of age (52%) and between five and 14 years of age (30%). Campylobacter infection occurred in 22% of all bacterial gastrointestinal diseases in the city of Sofia during the study period. Salmonella was the most frequently identified pathogen with 32%, followed by Shigella (30%), Campylobacter (22%) and diarrhoeagenic Escherichia coli (16%). The study shows that Campylobacter plays an important role as a bacterial cause of enterocolitis in Sofia, Bulgaria.

Campylobacteriosis and other bacterial gastrointestinal diseases in Sofia, Bulgaria for the period 1987-2008

Campylobacter is the most commonly reported enteric bacterial pathogen in humans. We still do not have any systematic data concerning campylobacteriosis in Bulgaria. For that reason, we present data of the thermophilic Campylobacter jejuni and Campylobacter coli in the aetiology of diarrhoeal diseases in Sofia, for the period from 1987 to 2008. The study included patients from 0 to over 65 years-old. A total of 51,607 faecal specimens were screened for Campylobacter. C. jejuni and C. coli were detected in 3.58% (1,847) of the strains, with the highest percentage in 1988 (7.5%) and the lowest in 2006 (0.3%). Campylobacteriosis occurred most frequently in the wet months of March, April, May and June, with 105, 102, 124 and 141 cases, respectively, and was rare in January with 25 cases. The most affected groups were children between 0 and 4 years of age (52%) and between five and 14 years of age (30%). Campylobacter infection occurred in 22% of all bacterial gastrointestinal diseases in the city of Sofia during the study period. Salmonella was the most frequently identified pathogen with 32%, followed by Shigella (30%), Campylobacter (22%) and diarrhoeagenic Escherichia coli (16%). The study shows that Campylobacter plays an important role as a bacterial cause of enterocolitis in Sofia, Bulgaria.

[Fatigue and anemia]

We herein report on an 80-year old male patient with a history of muscle weakness, fatigue and weight loss since several months. Because of a pathologic synacthen test in combination with decreased levels of ACTH, we diagnosed a secondary chronic adrenal insufficiency. Because of a normochromic, normocytic, and hypo-proliferative anemia, bone marrow puncture was performed, showing an anemia of chronic disease. We initiated hydrocortisone and anemia and patients' symptoms were fully reconstituted.

Graviperception in ciliates: steps in the transduction chain

Ciliates represent suitable model systems to study the mechanisms of graviperception and signal transduction as they show clear gravity-induced behavioural responses (gravitaxis and gravikinesis). The cytoplasm seems to act as a "statolith" stimulating mechanosensitive ion channels in the cell membrane. In order to test this hypothesis, electrophysiological studies with Stylonychia mytilus were performed, revealing the proposed changes (de- or hyperpolarization) depending on the cell's spatial orientation. The behaviour of Paramecium and Stylonychia was also analyzed during variable acceleration conditions of parabolic flights (5th German Parabolic Flight Campaign, 2003). The corresponding data confirm the relaxation of the graviresponses in microgravity as well as the existence of thresholds of graviresponses, which are found to be in the range of 0.4xg (gravikinesis) and 0.6xg (gravitaxis).

Dynamical model and nonextensive statistical mechanics of a market index on large time windows

The shape and tails of partial distribution functions (PDF) for a financial signal, i.e., the S&P500 and the turbulent nature of the markets are linked through a model encompassing Tsallis nonextensive statistics and leading to evolution equations of the Langevin and Fokker-Planck type. A model originally proposed to describe the intermittent behavior of turbulent flows describes the behavior of normalized log returns for such a financial market index, for small and large time windows, and both for small and large log returns. These turbulent market volatility (of normalized log returns) distributions can be sufficiently well fitted with a chi(2) distribution. The transition between the small time scale model of nonextensive, intermittent process, and the large scale Gaussian extensive homogeneous fluctuation picture is found to be at ca. a 200 day time lag. The intermittency exponent kappa in the framework of the Kolmogorov log-normal model is found to be related to the scaling exponent of the PDF moments, thereby giving weight to the model. The large value of kappa points to a large number of cascades in the turbulent process. The first Kramers-Moyal coefficient in the Fokker-Planck equation is almost equal to zero, indicating "no restoring force." A comparison is made between normalized log returns and mere price increments.

Reply to "Comment on 'Power-law correlations in the southern-oscillation-index fluctuations characterizing El Niño'"

Earlier [Phys. Rev. E 63, 047201 (2001)] we studied the southern oscillation index (SOI). Our findings tended to favor specific physical models for the El Niño description. The Comment by Metzler [Phys. Rev. E 67, 018201 (2003)] on this publication does not give any argument in favor of another El Niño physical model. In contrast, the Comment points out that statistical properties of the SOI data can be explained with a model based on a linear autoregressive process, but such a modeling does not help in identifying the relevant physical mechanisms.

The status of antimicrobial resistance of Helicobacter pylori in eastern Europe

OBJECTIVE

To evaluate the primary, secondary and combined resistance to five antimicrobial agents of 2340 Helicobacter pylori isolates from 19 centers in 10 countries in eastern Europe.

METHODS

Data were available for centers in Bulgaria, Croatia, the Czech Republic, Estonia, Greece, Lithuania, Poland, Russia, Slovenia and Turkey. Susceptibility was tested by agar dilution (seven countries), E test (five countries) and disk diffusion (three countries) methods. Resistance breakpoints (mg/L) were: metronidazole 8, clarithromycin 1, amoxicillin 0.5, tetracycline 4, and ciprofloxacin 1 or 4 in most centers. Primary and post-treatment resistance was assessed in 2003 and 337 isolates respectively. Results for 282 children and 201 adults were compared.

RESULTS

Primary resistance rates since 1998 were: metronidazole 37.9%, clarithromycin 9.5%, amoxicillin 0.9%, tetracycline 1.9%, ciprofloxacin 3.9%, and both metronidazole and clarithromycin 6.1%. Isolates from centers in Slovenia and Lithuania exhibited low resistance rates. Since 1998, amoxicillin resistance has been detected in the southeastern region. From 1996, metronidazole resistance increased significantly from 30.5% to 36.4%, while clarithromycin resistance increased slightly from 8.9% to 10.6%. In centers in Greece, Poland, and Bulgaria, the mean metronidazole resistance was slightly higher in adults than in children (39% versus 31.2%, P > 0.05); this trend was not found for clarithromycin or amoxicillin (P > 0.20). Post-treatment resistance rates exhibited wide variations.

CONCLUSIONS

In eastern Europe, primary H. pylori resistance to metronidazole is considerable, and that to clarithromycin is similar to or slightly higher than that in western Europe. Resistance to amoxicillin, ciprofloxacin and tetracycline was detected in several centers. Primary and post-treatment resistance rates vary greatly between centers.

Power-law correlations in the southern-oscillation-index fluctuations characterizing El Niño

The southern oscillation index (SOI) is a characteristic of the El Niño phenomenon. SOI monthly averaged data is analyzed for the time interval 1866-2000. The tail of the cumulative distribution of the fluctuations of SOI signal is studied in order to characterize the amplitude scaling of the fluctuations and the occurrence of extreme events. Large fluctuations are more likely to occur than the Gaussian distribution would predict. The time scaling of fluctuations is studied by applying the energy spectrum and the detrended fluctuation analysis statistical method. Self-affine properties are found to be pertinent to the SOI signal and therefore suggest power-law correlations of fluctuations of the signal. An antipersistent type of correlations exists for a time interval ranging from about 4 months to about 6 years. This leads to favoring specific physical models for El Niño description.

Differential expression of functional guanylyl cyclases in melanocytes: absence of nitric-oxide-sensitive isoform in metastatic cells

Nitric oxide (NO) is a reactive endogenous molecule with multiple functions and its cellular signaling activity is mainly mediated by activation of the soluble isoform of guanylyl cyclase, a heterodimeric (alpha/beta) hemeprotein. The expression of the NO-sensitive soluble isoform of guanylyl cyclase was studied in various cultured melanocytic cells by measuring the accumulation of guanosine 3',5'-cyclic monophosphate in the presence and absence of NO donors. Here we report that 3-morpholino-sydnonimine, a donor of NO redox species, and (Z)-1-[2- (2-aminoethyl)-N-(2-ammonioethyl)amino]diazen-1-ium-1,2-diolate, a direct NO donor, induced a 20-fold increase in intracellular guanosine 3',5'-cyclic monophosphate in nonmetastatic melanoma cells and normal melanocytes in culture that could be related to cellular melanin content in a concentration-dependent manner. The increased intracellular guanosine 3',5'-cyclic monophosphate was due to stimulation of the activity of soluble guanylyl cyclase as such increase was completely abolished by using a specific inhibitor of soluble guanylyl cyclase. The involvement of functional soluble guanylyl cyclase was further confirmed by the presence of alpha1 and beta1 subunits in these cells at both mRNA and protein levels. In contrast, none of the NO donors induced guanosine 3',5'-cyclic monophosphate production in metastatic melanoma cells, which could be attributed to the absence of the beta1 subunit that is essential for catalytic activity of the soluble isoform of guanylyl cyclase. Metastatic melanoma cells produced higher levels of intracellular guanosine 3',5'-cyclic monophosphate in response to natriuretic peptides than other cell types, however, due to upregulation of membrane-bound guanylyl cyclase activities, but they are less pigmented or unpigmented. The present finding suggests that NO signaling in association with melanogenesis is dependent on the soluble isoform of guanylyl cyclase, whereas absence of soluble guanylyl cyclase but the presence of membrane-bound guanylyl cyclase correlates with the metastatic behavior of melanoma cells.

Incidence of dental caries /Is/ on milk molars /M1,M2/ in 3-8 year-old children from Plovdiv

The incidence of dental caries /Is/ on deciduous molars in 1216 children aged 3 to 8 from Plovdiv has been studied. The results showed highest Is in the fissures of m1 and m2 and lowest Is on the smooth surfaces. The incidence of dental caries is getting higher with statistically significant differences in the lower jaw up to the 6th year and in the upper jaw up to 7th year of age. Is in the lower jaw is higher than that of the upper jaw only in the fissures.

Topographic distribution of occlusal contacts of the first mandibular molar--comparative study

The specification of the occlusal contacts in the posterior teeth region is a necessary clinical reference point for creating optimal interrelations between the teeth and dentition. The methods, such as the photo-occlusal method, the quasiplanimetric method, two-phase proof imprint in central occlusion, recording of contacts with profile wax, that have been used in studying the number and location of occlusal contacts at various positions of the mandible in relation to the maxilla are exact but difficult to apply clinically. The purpose of the present study is to find the topographic distribution of occlusal contacts in intact first mandibular molars using a method that is easy to utilise clinically and to compare the present results with the findings of the authors. The masticatory teeth of 100 high-school students (18 years old) without subjective complaints or objective structural or functional disorders of the temporomandibular joint were studied by means of articulation paper. From that sample 41 students with intact dentition and orthognathic occlusion were selected. The first mandibular molars (N = 77) were studied. The results are as follows. The occlusal contacts in the first mandibular molar vary from 1 to 7. The greatest percentage of contacts is observed in the tubercles. In the first mandibular molar the biting pressure upon the tubercle apex areas is greater compared to that on the sloping areas. Our results were compared with the findings obtained by the other three methods mentioned above. Our method allows objective specification of the topographic distribution of occlusal contacts.

Involvement of the second messenger cAMP in gravity-signal transduction in Physarum

The aim of the investigation was to clarify, whether cellular signal processing following graviperception involves second messenger pathways. The test object was a most gravisensitive free-living ameboid cell, the myxomycete (acellular slime mold) Physarum polycephalum. It was demonstrated that the motor response is related to acceleration-dependent changes in the levels of the cellular second messenger cyclic adenosine monophosphate (cAMP). Rotating Physarum plasmodia in the gravity field of the Earth about a horizontal axis increased their cAMP concentration. Depriving the cells for a few days of the acceleration stimulus (near weightlessness in a space experiment on STS-69) slightly lowered plasmodial cAMP levels. Thus, the results provide first indications that the acceleration-stimulus signal transduction chain of Physarum uses an ubiquitous second messenger pathway.

Comparative studies of the graviresponses of Paramecium and Loxodes

Gravitactic protozoa offer advantages in studying how the gravity stimulus is perceived on the cellular level. By means of a slow rotating centrifuge microscope in space the acceleration thresholds for gravitaxis of Loxodes striatus and Paramecium biaurelia were determined: < or = 0.15 x g for Loxodes and 0.3 x g for Paramecium, indicating different sensitivities of these species. Neutral-buoyant densities of immobilized cells were determined using media of different densities, revealing densities of 1.03 to 1.035 g/cm3 for Loxodes and 1.04 g/cm3 to 1.045 g/cm3 for Paramecium. Behavioral studies revealed that gravitaxis of Loxodes persisted independent of the density of the medium. In contrast, negative gravitaxis of Paramecium was no longer measurable if the density of the medium approached the density of the cell. The results suggest that in the case of Loxodes gravity is perceived by an intracellular receptor and, in the case of Paramecium by its own mass via the pressure on the lower cell membrane.

Effect of nitric oxide on the adhesion of human melanocytes to extracellular matrix components

The aim of the present study was to explore whether nitric oxide (NO) interferes with the attachment of human melanocytes to the extracellular matrix (ECM) components. Consequently, the effects have been investigated of the NO-releasing compounds 3-morpholino-sydnonimine (SIN-1) and S-nitroso-glutathione (GSNO) on the in vitro adhesion of human melanocytic cells to fibronectin. The NO donors induced a concentration-dependent reduction in the adhesion of both 51CrO4(2-)-labelled melanocytes and melanoma cells to fibronectin. Pigmented M14 melanoma cells were more susceptible to the effect of SIN-1 (half-maximal inhibiting effect at about 0.5 mM) than normal human melanocytes and also than the non-pigmented melanoma cells Mel57 (half-maximal inhibiting effects between 0.9 and 2 mM). This effect of SIN-1 also appeared to be related to the melanin content of normal melanocytes, whereas GSNO was significantly less active. Both flow cytometric analysis and immunocytochemical staining showed expression of neuronal NO synthase in all cell lines. The results of this study suggest that aberrant in vivo production of NO during infection and inflammation may contribute to loss of melanocytes in, for example, vitiligo, by reducing de novo attachment of melanocytes to the ECM. These findings could also be important for understanding the process of metastasis.

Bilophila wadsworthiain Brain Abscess: Case Report

A case of a patient with a 20-year history of chronic otitis media complicated by cholesteatoma and brain abscess is described. A CT scan with contrast material showed three abscess cavities in the right cerebellar hemisphere. A culture from a specimen of the cholesteatoma yielded a significant amount of growth of Bilophila wadsworthia, Bacteroides fragilis and Prevotella oris and a moderate growth of alpha-streptococci and Staphylococcus simulans. From the pus of the brain abscess we also isolated numerous Bilophila wadsworthia, Bacteroides fragilis and Prevotella oris and some Prevotella buccae and Peptostreptococcus anaerobius. No aerobes were present. The patient underwent a craniotomy and the biggest abscess was removed together with the capsule. The antimicrobial therapy included penicillin plus metronidazole and later augmentin. The result of the treatment was a complete cure and total recovery of the patient. This is the first documentation of isolation of B. wadsworthia in chronic otitis media and in brain abscess.

Gravity perception and signal transduction in single cells

Cellular signal processing in multi-, as well as in unicellular organisms, has to rely on fundamentally similar mechanisms. Free-living single cells often use the gravity vector for their spatial orientation (gravitaxis) and show distinct gravisensitivities. In this investigation the gravisensitive giant ameboid cell Physarum polycephalum (Myxomycetes, acellular slime molds) is used. Its gravitaxis and the modulation of its intrinsic rhythmic contraction activity by gravity was demonstrated in 180 degrees-turn experiments and in simulated, as well as in actual, near-weightlessness studies (fast-rotating clinostat; Spacelab D1, IML-1). The stimulus perception was addressed in an IML-2 experiment, which provided information on the gravireceptor itself by the determination of the cell's acceleration-sensitivity threshold. Ground-based experiments designed to elucidate the subsequent steps in signal transduction leading to a motor response, suggest that an acceleration stimulus induces changes in the level of second messenger, adenosine 3',5'-cyclic monophosphate (cAMP), indicating also that the acceleration-stimulus signal transduction chain of Physarum uses an ubiquitous second messenger pathway.

Dental caries-reducing effects of a milk fluoridation project in Bulgaria

OBJECTIVES

The aim of the present study was to investigate the effects of a community-based milk fluoridation project on dental caries.

METHODS

Fluoridated milk was provided to about one-half of kindergarten and other schoolchildren in Asenovgrad, a town in the southern part of Bulgaria. The estimated daily milk consumption was 200 ml containing 1 mg of fluoride (approximately 5 ppm F). Cross-sectional samples of 6 1/2-year-olds in Asenovgrad and Panaguriche (a nearby town selected as the reference community) were examined at the start of the study in 1988 and after three years. Additional cross-sectional samples of 7 1/2-year-olds in Asenovgrad who were and were not drinking fluoridated milk were examined at baseline and at three years to provided an internal control group. Samples of 6 1/2 and 8 1/2-year-olds from Asenovgrad and Karlovo were examined in 1993 to provide for five-year follow-up comparisons.

RESULTS

In 6 1/2-year-old children who had consumed fluoridated milk for three years, there was a decrease in the mean dmft per child of 40 percent and in the mean DMFT of 89 percent compared to children examined at baseline. Children in Asenovgrad who were 4 1/2 years old at the start of the study and had been drinking fluoridated milk for three years had on average 44 percent fewer dmft and 83 percent fewer DMFT at 7 1/2 years of age than those not drinking fluoridated milk. After five years the dmft index was 40 percent less and the DMFT index 79 percent less in those children who had participated in the full five years of the program compared to the control group.

CONCLUSIONS

Results seem to confirm the caries-reducing effects of milk fluoridation found in previous studies. Unexpected large caries reductions obtained in this nonexperimental study, however, probably cannot be attributed to the fluoridation of milk alone. The mere introduction of the project might have led to other changes affecting dental caries, such as improved oral hygiene and better dietary habits.

Caries reduction by milk fluoridation in Bulgaria

The aim of the present study has been to investigate the caries-reducing effect of a community-based milk fluoridation project. In those Kindergartens where fluoridated milk had been delivered on a regular basis, the estimated consumption corresponded to a daily intake of 200 mL milk containing 1 mg F- (5 ppm F-) for periods of 180-200 days per year. A total of 204 six-year-old children, randomly selected, was examined at baseline and three and a half years after the start of the project. A statistically significant reduction in the prevalence of dental caries was obtained for those children who had received fluoridated milk on a regular basis. In six-year-old children, the reduction in the dmft figure was 40% and in the DMFT figure, 90%. Despite the deficiencies in the design of this study (dictated by local circumstances), the results confirm the findings of other studies on the caries-reducing effect of fluoridated milk. The results also confirm that the earlier in the child's life the consumption of fluoridated milk starts, the better the effect.