Showing papers by "University of Turku published in 1987"

Healing of periapical lesions of pulpless teeth after endodontic treatment with controlled asepsis.

Abstract: Using a careful anaerobic bacteriological technique, bacteria were shown to be eliminated from infected root canals before the endodontic treatment was finished by root filling. Healing of the periapical lesions of the teeth was followed for 2–5 yr. The majority of the 79 lesions healed completely or decreased in size in such a way that they could be expected to heal. In 5 cases there was no or only an insignificant decrease in the size of the lesions. Two of these lesions were shown to contain bacteria of the species Actinomyces or Arachnid. In another case there were dentin chips in the periapical tissue. Periapical lesions which fail to heal in spite of careful bacteriological monitoring of the endodontic treatment may in some cases be due to an establishment of the bacteria outside the root canal in the periapical tissue. In these sites, the bacteria are inaccessible to conventional endodontic treatment.

Relationship of protein flexibility to thermostability

Abstract: Thermostability of proteins arises from the simultaneous effect of several forces, which in fact lead to decreased flexibility of the polypeptide chain. This is verified by flexibility indices, which are derived from normalized B-values of individual amino acids in several refined three-dimensional structures. Flexibility indices show that overall flexibility is reduced when thermostability is increased. Protein molecules require both flexibility and rigidity to function, but the higher the temperature optimum and stability the more rigid is the structure needed to compensate for increased thermal fluctuations. Flexibilities of proteins performing the same catalytic activity seem to be about the same at their temperature optima, but the more rigid thermostable proteins reach the flexibility of thermolabile proteins at higher temperatures. In several proteins such as allosteric enzymes, some local sites of flexibility are highly conserved. The relevance of reduced flexibility to overall stability of proteins is also discussed. Flexibility indices and profiles can be used in the design of more stable proteins by site-directed mutagenesis.

Fluvial perturbance in the Western Amazon basin: regulation by long-term sub-andean tectonics.

Abstract: Haffer's refuge theory proposes that during the arid climatic phases of the late Pleistocene, tropical lowland forests of Amazonia were reduced to isolated patches contributing to the high species richness of the present-day forest. The theory was developed because no obvious historic or modern geomorphic isolation barriers were recorded in Amazonia. Analyses of radar images combined with stratigraphical data show that in the basinal forelands of the tectonically active Andes the geological setting causes long-term fluvial perturbance. This leads to a temporally structured highly complex mosaic of fossil and present floodplains. These dynamics have been present with varying activity and geographic range during the Tertiary and Quaternary, providing site-turnover that has not been recognized by the biogeographic tradition of the Amazon basin.

Evening primrose oil in the treatment of atopic eczema: effect on clinical status, plasma phospholipid fatty acids and circulating blood prostaglandins

Abstract: In a double-blind trial patients with atopic eczema received either oral evening primrose oil (EPO) (n = 14) or placebo (n = 11) for 12 weeks. In the EPO group a statistically significant improvement was observed in the overall severity and grade of inflammation and in the percentage of the body surface involved by eczema as well as in dryness and itch. Patients in the placebo group showed a significant reduction in inflammation. The patients receiving EPO showed a significantly greater reduction in inflammation than those receiving placebo. Evening primrose oil caused a significant rise in the amount of dihomogammalinolenic acid in the plasma phospholipid fatty acids. Plasma levels of TXB2, 6-keto-PGF1 alpha and PGE1, and the amount of TXB2 released into serum during clotting were not altered by evening primrose oil.

Hypokalaemia and other non-bronchial effects of inhaled fenoterol and salbutamol: a placebo-controlled dose-response study in healthy volunteers.

Abstract: 1. The hypokalaemia-inducing effects of two widely used inhaled antiasthmatic beta 2-adrenoceptor agonists, fenoterol and salbutamol, were compared in six healthy male volunteers. 2. Each drug was administered in three different doses, 400, 600 and 800 micrograms, which were repeated three times with 30 min intervals (total doses 1200, 1800 and 2400 micrograms in 1 h). The treatments were given at 1 week intervals in random order in a single-blind fashion. 3. The concentration of potassium in plasma was dose-dependently reduced by both drugs with peak effects 75-90 min after the first inhalations. The hypokalaemic effect of fenoterol was significantly greater than that of equal doses of salbutamol (average +/- s.d. reductions of 1.13 +/- 0.32 and 0.67 +/- 0.25 mEq l-1, respectively, after the highest doses, P less than 0.05). Concomitantly, decreases were noted in the amplitude of the T-wave on the ECG. 4. The concentration of cyclic AMP in plasma was measured and used as an indicator of systemic beta 2-adrenoceptor agonistic effects of the drugs. Increases in cAMP were a close mirror image of the drugs' effects on potassium in plasma. 5. Plasma renin activity, noradrenaline in plasma and heart rate were also dose-dependently increased by the treatments, whereas blood pressure remained unaltered. 6. While the clinical significance of hypokalaemia induced by inhaled beta 2-adrenoceptor sympathomimetics still is a matter of debate, our results point to possible differences between therapeutically equipotent doses of fenoterol and salbutamol in their propensity to cause hypokalaemia and other acute non-bronchial effects.

Febrile exudative tonsillitis: viral or streptococcal?

Abstract: A prospective 1-year study of acute febrile exudative tonsillitis in 110 children was carried out. Viral infection was associated with 42% of the cases, beta-hemolytic streptococci with 31% (12% group A), Mycoplasma pneumoniae with 5%, and unknown cause with 35%. More than one agent was implicated in 14% of the cases. Adenovirus was the viral agent most frequently (19%) recorded. Other viruses involved were Epstein-Barr virus, parainfluenza, influenza A, herpes simplex, and respiratory syncytial viruses. The responsible agent was found by rapid viral antigen detection in 20% of all cases and by rapid test for group A streptococcal antigen detection in 10%. Age was the most important factor in predicting the causative agent. Viral tonsillitis was most common in children younger than 3 years of age and group A beta-hemolytic streptococci tonsillitis in children 6 years of age or more. Clinical analysis of the illness, WBC count, and ESR did not reveal differences that could help in differentiating bacterial from viral tonsillitis. All patients were treated with a regimen of oral penicillin. Fever associated with group A beta-hemolytic streptococci tonsillitis responded to penicillin therapy significantly more rapidly than fever associated with viral infections. These observations demonstrate the prominent role of viruses in the etiology of febrile exudative tonsillitis, especially in young children, and reinforce the benefit of rapid tests before antibiotic therapy is started.

Detection of human papillomavirus (HPV) structural antigens and DNA types in inverted papillomas and squamous cell carcinomas of the nasal cavities and paranasal sinuses.

Abstract: To assess the suggested etiological role of human papillomavirus (HPV), biopsies from 14 patients operated on for an inverted papilloma (11 cases) and squamous cell carcinoma (3 cases) of the nasal cavity and paranasal sinuses were analysed for light microscopical evidence of HPV, by indirect immunoperoxidase (IP-PAP) to demonstrate HPV structural proteins, and using in situ DNA-hybridization to disclose the DNA of HPV types 6, 11 and 16. The majority of the inverted papillomas contained areas of metaplastic squamous cells, including koilocytes as well as dysplastic changes consistent with intra-epithelial neoplasia as described in uterine cervix. In 3 patients, frankly invasive squamous cell carcinomas were found, originating from dysplastic squamous epithelium. Of the 14 lesions, 7 (50%) expressed HPV antigens, usually confined to only a few cells close to the surface of the epithelium. None of the malignant lesions expressed HPV antigens. In situ DNA-hybridization disclosed HPV 11 DNA alone in 5 lesions, but none of the lesions contained HPV 6 DNA. HPV 16 DNA was found in 2 lesions as a single HPV type, and in 3 other lesions concomitant with HPV 11. All three carcinomas contained HPV 16 DNA. The HPV DNA distribution proved to be different from that found in the genital tract HPV lesions; HPV DNA was less abundant in the nasal papillomas, and it was also found in the basal and suprabasal cells.(ABSTRACT TRUNCATED AT 250 WORDS)

Factors Affecting the Occurrence of Acute Otitis Media during the First Year of Life

Abstract: A regional birth cohort of 5,356 infants was enrolled into a follow-up study in order to investigate the determinants of the development of infectious diseases in children. The infants were examined at three months, six months and twelve months of age by the physicians at the well-baby clinics. At these occasions the number of episodes of acute otitis media in the infants, the duration of breast-feeding, the number of siblings, the type of day care, parental smoking, the presence of animal pets at home and the number and type of other illnesses than otitis were registered. Two thirds of the infants had no episodes of acute otitis media. The median age for the first episode of acute otitis media was eight months. About 10% of the infants had experienced recurrent otitis media (three episodes or more) during their first year of life. Significant associations were found between the occurrence of acute otitis media and the number of siblings, the type of day care, the sex of the infant, the duration of breast feeding, maternal socioeconomic status and prematurity.

Oral premedication with clonidine: effects on stress responses during general anaesthesia.

Abstract: The effect of clonidine (4.5 micrograms kg-1) on haemodynamics and hormonal stress responses was evaluated in 21 female patients undergoing breast surgery. The standardized general anaesthesia included diazepam as premedicant, thiopentone, enflurane, N2O, fentanyl and vecuronium. Venous plasma concentrations of noradrenaline, adrenaline, growth hormone, vasopressin, and cortisol were assayed at various times before, during and after surgery. Clonidine attenuated the sympathoadrenal response; arterial blood pressure and heart rate increases in association with intubation were lower in clonidine-premedicated patients. Noradrenaline levels were lower throughout and 3 h after surgery in the clonidine group (P less than 0.05). Adrenaline levels were lower in this group 2 min after intubation (P less than 0.05). Growth hormone, vasopressin and cortisol plasma levels were increased at the end of and after surgery, with no differences between the groups. In spite of the effect on sympathoadrenal response, clonidine did not have any significant additive anxiolytic effect. Statistically significant differences were not found as to need for postoperative analgesics.

Immunohistochemical identification of macrophages, lymphoid cells and HLA antigens in the human testis.

Abstract: The presence and distribution of macrophages, several subtypes of lymphocytes and HLA antigens in the human testis were studied using monoclonal antibodies and immunocytochemical staining. Cells identified as tissue macrophages were relatively abundant. They were dispersed individually in the interstitium and were often included in Leydig cell clusters. Occasional macrophages were observed in the tubular wall, but never in the seminiferous tubules. Very few lymphocytes were found in the testicular interstitium. These were mainly T lymphocytes. T helper/inducer and T cytotoxic/suppressor cells were extremely scarce. B1 + cells were not observed, but occasional Leu-14+ cells could be seen. NK cells were not found. The number of T lymphocytes in the tunica albuginea was considerably higher than in the interstitial tissue. HLA-ABC and HLA-DR antigens could be observed in the endothelial cells and macrophages which were both strongly positive. The myoid cells and the Leydig cells expressed these antigens only weakly. Neither of the HLA antigens was expressed in the germinal epithelium.

Growth of 519 Small for Gestational Age Infants during the First Two Years of Life

Abstract: . The physical growth of 519 small for gestational age infants (SGA), with a birth weight below the 10th percentile on our own growth curve, born in the region of University Central Hospital of Turku during the period June 1,1981-May 31, 1982, was studied. The study population consists of 4 517 term, appropriate for gestational age (AGA) infants, 488 term SGA infants, 320 preterm AGA infants and 31 preterm SGA infants. The degree of intrauterine growth retardation (IUGR) seemed to have an effect on physical growth in term SGA infants. Those term SGA infants with a low Ponderal Index (PI) (type II) were taller and had a larger head circumference at the age of 24 months than term SGA infants with adequate PI (type I). Among the preterm SGA infants the degree of IUGR seemed to have no effect on later growth. Smoking is still one of the main risk factors associated with poor intrauterine growth. In this study we also found that smoking has an effect on later growth; the children of smoking mothers were smaller than those of non-smoking mothers in the AGA group. Among the SGA infants the infants of non-smoking mothers were bigger than those of smoking mothers. This difference could be explained by other factors associated with SGA. We found that in spite of the catch-up growth during the first months, 26% of the severely SGA infants (birth weight below the 2.5th percentile) still had a weight below the 2.5th percentile at the age of 24 months.

Antimicrobial Factors in Saliva: Ontogeny and Relation to Oral Health

Abstract: Antimicrobial agents (antibody and non-antibody) present in human saliva protect oral tissues by a variety of mechanisms, such as prevention of bacterial adhesion, agglutination of micro-organisms, and inhibition of multiplication and metabolism. However, studies in which the concentrations of various salivary antimicrobial agents have been correlated to the presence and severity of oral diseases--of dental caries, in particular--have produced controversial data, and it seems evident, also on the basis of the present study, that no single salivary antimicrobial factor (except flow rate) affects oral health to a significant degree. In the present study, we report the levels of some selected salivary antimicrobial agents in predentate and dentate human infants, with a comparison to the levels found in young adults' saliva. Salivary lysozyme, peroxidase, and hypothiocyanite concentrations were already at the adult level at the time when the primary teeth erupt, whereas immunoglobulin (IgA, IgG, and IgM), lactoferrin, myeloperoxidase, and thiocyanate concentrations were significantly lower in children than in adults. Dentate children had more IgG, thiocyanate, and protein in whole saliva than did predentate children.

Sedative and cardiovascular effects of medetomidine, a novel selective alpha 2-adrenoceptor agonist, in healthy volunteers.

Abstract: 1. Single intravenous doses (25, 50 and 100 micrograms) of medetomidine (MPV-785, an imidazole derivative), a selective alpha 2-adrenoceptor agonist, were administered to eight healthy male volunteers in a double-blind, placebo-controlled study. 2. The following dose-related effects, all of which were compatible with an agonistic action of the drug at alpha 2-adrenoceptors, were noted: reductions of systolic and diastolic blood pressure (maximum 18/11 mm Hg), heart rate (maximum 10 beats min-1), saliva secretion (maximum 84%) and noradrenaline levels in plasma (maximum 70%). 3. Dose-dependent sedation or impairment of vigilance was also observed, both by subjective and objective (critical flicker fusion threshold) assessments, with the highest dose actually inducing sleep in five of the subjects. 4. The observed effects were in general agreement with those previously seen after intravenous administration of the centrally acting antihypertensive alpha 2-adrenoceptor activating drug, clonidine, but of a shorter duration. 5. The relative importance of alpha 2-adrenoceptors located in peripheral tissues and in the central nervous system for the drug's cardiovascular effects could not be determined, but the high lipid solubility of the compound and the rapid onset of sedation are in favour of a major central component. 6. Medetomidine may be a useful tool for the investigation of the physiology and pharmacology of alpha 2-adrenoceptors in man. In addition, the therapeutic and diagnostic uses of the compound should be investigated in pathological conditions related to increased sympathetic neuronal activity.

Epidermal growth factor increases collagen production in granulation tissue by stimulation of fibroblast proliferation and not by activation of procollagen genes.

Abstract: The effects of epidermal growth factor (EGF) on granulation-tissue formation and collagen-gene expression were studied in experimental sponge-induced granulomas in rats. After daily administration of 5 micrograms of EGF into the sponge, total RNA was extracted from the ingrown granulation tissue at days 4 and 7 and analysed by Northern hybridization for the contents of mRNAs for types I and III procollagens. EGF treatment increased procollagen mRNA, particularly at day 4. To determine whether this elevation was due to increased proliferation of collagen-producing fibroblasts or to activation of collagen-gene expression in these cells, fibroblast cultures were started from granulation tissue and treated with EGF. These experiments confirmed that EGF is a potent mitogen for granuloma fibroblasts in a dose-dependent manner. The effect of EGF treatment on radioactive hydroxyproline production in cultured cells was inhibitory. The decreased rate of collagen synthesis was also indicated by decreased amounts of procollagen mRNAs. The results suggest that the stimulation of wound healing and collagen production by EGF is due to increased fibroblast proliferation, and not to increased expression of type I and III procollagen genes.

47,XXX females, sex chromosomes, and tooth crown structure

Abstract: Enamel thickness of the maxillary permanent central incisors and canines in seven Finnish 47,XXX females, their first-degree male and female relatives, and control males and females from the general population were determined from radiographs. The results showed that enamel in teeth of 47,XXX females was clearly thicker than that of normal controls. On the other hand, the thickness of "dentin" (distance between mesial and distal dentinoenamel junctions) in 47,XXX females' teeth was about the same as that in normal control females, but clearly reduced as compared with that in control males. It is therefore obvious that in the triple-X chromosome complement the extra X chromosome is active in amelogenesis, whereas it has practically no influence on the growth of dentin. The calculations based on present and previous results in 45,X females and 47,XYY males indicate that the X chromosome increases metric enamel growth somewhat more effectively than the Y chromosome. Possibly, halfway states exist between active and repressed enamel genes on the X chromosome. The Y chromosome seems to promote dental growth in a holistic fashion.

Hereditary multi-infarct dementia

Abstract: This paper summarizes the clinical and genetic features of a disease occurring in 16 patients from the same extended family, which resembles the multi-infarct dementia described by Sourander and Walin

Laminin in traumatized peripheral nerve: basement membrane changes during degeneration and regeneration.

Abstract: The changes in Schwann cell basement membrane associated with degeneration and regeneration during 50 weeks after transection of rat sciatic nerve were studied immunohistochemically with antibodies to laminin. In half of the animals, regeneration was prevented by suturing the nerve stumps aside, whereas in the rest spontaneous regeneration was allowed. Axonal regeneration was monitored with anti-neurofilament protein antibodies. In control nerves, basement membranes surrounding Schwann cells were visualized as circular, laminin-positive structures within the endoneurium. By 8 weeks after transection, Schwann cells had formed columns which were laminin-positive throughout their cross-sectional area and indistinguishable from basement membrane zones in both non-regenerating and regenerating nerves. As axons repopulated the distal stump, the normal shape of Schwann cell basement membrane tubes was slowly restored in freely regenerating nerves. In non-regenerating nerves, however, a striking atrophy of Schwann cell columns was observed. Regenerating axons were only seen inside laminin-positive tubular structures in all phases after 8 weeks in regenerating nerves. On the other hand, restoration of normal shape in laminin-positive basement membrane zones was coincident with appearance of axons in the distal stump, but it did not take place in chronically degenerating nerves. The results show that chronic degeneration leads to an atrophy of Schwann cell columns and results in a decrease in laminin immunoreactivity associated with them.

Coordinated regulation of type I and type III collagen production and mRNA levels of pro alpha 1(I) and pro alpha 2(I) collagen in cultured morphea fibroblasts.

Abstract: Fibroblast cultures were started from affected and unaffected skin areas of six patients with localized scleroderma in an active stage. The cell lines were studied for synthesis of procollagens and fibronectin by metabolic labeling with 3H-proline and for their contents of mRNAs for pro alpha 1(I) and pro alpha 2(I) collagen. For this purpose a cDNA clone for human pro alpha 1(I) collagen mRNA was constructed. The clone was identified by restriction site mapping and hybridization to the specific mRNAs. All the scleroderma fibroblast lines produced increased amounts of type I and type III collagens and fibronectin during the early passages. The cell lines gradually reduced their elevated synthesis of collagen and fibronectin to normal or near normal levels by the tenth passage. The ratios of alpha 1(I) and alpha 2(I) chains and of type I and type III collagens, and the extent of type I procollagen processing, remained relatively unchanged in all the cultures. The cellular levels of type I procollagen mRNAs were increased in all the cells exhibiting an increased synthesis of collagen. The results suggest that in localized scleroderma the fibroblasts have undergone a coordinated activation of collagen synthesis at transcriptional level.

Estimation of long-term salivary gland damage induced by radiotherapy.

Abstract: A classification is proposed for estimating salivary gland damage induced by radiotherapy to the head and neck. The volume of salivary glands irradiated was evaluated, and their relative proportions of whole saliva output were calculated. Stimulated salivary flow rate was measured in 61 patients treated with radiotherapy for head and neck malignancies. A highly significant negative correlation was found between the classification of salivary gland damage and stimulated salivary flow rate. The volume of the major salivary glands irradiated seems to be the most important factor affecting the postirradiation salivary flow after a curative dose of radiotherapy. If possible, partial sparing of the salivary glands may help to keep the patient's salivary secretion at an acceptable level and promote protection against dental caries. Most patients irradiated to the head and neck, however, need an effective prophylactic programme for the rest of their lives in order to preserve their teeth.

Alzheimer's disease: neuropathological correlates of cognitive and motor disorders.

Abstract: Correlations between clinical symptoms and changes in brain neuropathology were investigated in 34 patients with Alzheimer's disease, who were compared with 17 non-demented, age-matched controls. The patients were originally found in a community survey of dementia and were followed up prospectively until death. A highly significant correlation emerged between the severity of dementia and the numbers of plaques and tangles in the material as a whole, but no essential difference was found between severely and less severely demented patients. Low brain weight correlated highly with many clinical symptoms and signs and the severity of dementia. A multiple regression model consisting of plaques and tangles in amygdala, gyrus frontalis medius, gyrus angularis, and gyrus temporalis medius, plaques of gyrus rectus, tangles of the hippocampus, gyrus precentralis and gyrus cinguli together with brain weight, emerged to link dementia to neuropathological changes at the level of maximum significance. Dyskinetic movements were associated with damage of several brain areas, implying a multiple etiology.

IgA anti‐endomysial antibodies in dermatitis herpetiformis: correlation with jejunal morphology, gluten‐free diet and anti‐gliadin antibodies

Abstract: SUMMARY Circulating IgA-class anti-endomysium antibodies (EmA) can be detected by indirect immunofiuorescence on monkey oesophagus sections. We found EmA in 22 (76%) of 29 patients with dermatitis herpetiformis (DH) on a normal, gluten-containing diet. The highest frequency (100%) of EmA was observed in patients with sub-total villous atrophy. IgA-class antigliadin antibodies (AGA) were found using an ELISA method in 59% of 29 DH patients and in 86% of those with sub-total villous atrophy. There was a significant correlation between EmA litres and AGA levels in individual patients. Gluten-free diet (GFD) treatment caused a rapid decrease in EmA litres; only three of the 12 patients still showed raised EmA after 6–12 months on a GFD and two of these three had failed to adhere to a strict diet. In contrast, no decrease in EmA titres occurred in four patients maintained on a normal diet, and two of the three patients with initially negative EmA developed positive titres when continuing on a normal diet. These results show that both IgA-class EmA and AGA are good indicators of jejunal damage in DH. The rapid fall of EmA titres after gluten withdrawal indicates that this test is also useful for monitoring a patient's adherence to a GFD.

Childhood bacterial meningitis: initial symptoms and signs related to age, and reasons for consulting a physician

Abstract: The relationship of symptoms and signs to age and the reasons for consulting a physician were analyzed in 110 cases of culture-proven childhood bacterial meningitis. H. influenzae caused 74, meningococci 28, pneumococci 6 and streptococci 2 of the cases. Apart from fever (present in 94%), the most common symptoms according to age were as follows: 1–5 months: irritability (85%), 6–11 months: impaired consciousness (79%), 12 months or more: vomiting (82%) and neck rigidity (78%). Absence of neck rigidity at diagnosis was associated with young age (<12 months, P<0.001) and, in older children, to a short duration of symptoms (P<0.01) but not to the degree of CSF pleocytosis. Symptoms of meningitis caused by H. influenzae differed from those of meningococcal meningitis. Meningitis should be suspected in irritable or lethargic febrile children despite absence of neck rigidity. Fever and vomiting were the most frequent reasons for consulting a physician (60% and 31%, respectively). Despite the frequency and alarming character of irritability, impaired consciousness and neck rigidity, their presence led infrequently to a consultation (6%, 22% and 3%, respectively). Parental ignorance of such symptoms or of their importance may cause treatment delay, despite readily available medical services.