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Biomedical subjects

J Peltola

Publications and source records attributed to J Peltola.

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

Pilot-scale demonstration of a two-stage methanotrophic bioreactor for biodegradation of trichloroethylene in groundwater.

A two-stage methanotrophic bioreactor system was developed for remediation of water contaminated with TCE and other chlorinated, volatile, aliphatic hydrocarbons. The first stage of the reactor was a suspended-growth culture vessel using a bubbleless methane-transfer device. The second stage was a plug-flow bioreactor supplied with contaminated groundwater and cell suspension from the culture vessel. The test objectives were to determine the applicability of microbial culture conditions reported in the literature for continuous, pilot-scale TCE treatment; the technical feasibility of plug-flow bioreactor design for treatment of TCE; and the projected economic competitiveness of the technology considering the cost of methane for growth of methanotrophs. The methanotrophic organism used in the study was Methylosinus trichosporium OB3b. Information on system operation was obtained in bench tests prior to conducting the pilot tests. In bench- and pilot-scale tests, variability in the degree of TCE degradation and difficulty in maintaining the microbial culture activity led to short periods of satisfactory biotreatment. Further development of the microbial culture system will be required for long-term operation. During transient periods of high TCE degradation activity, the bioreactor concept proved feasible by exhibiting both a high degree of TCE biodegradation (typically about 90% at influent TCE concentrations of 0.5-4 ppm) and a close approximation to first-order reactor kinetics throughout the length of the reactor. Actual methane usage in the pilot-scale reactor resulted in projected methane costs of $0.33 per 1000 gallons of water treated. This cost theoretically would be reduced by system modifications. The theoretical minimum methane cost was approximately $0.05 per 1000 gallons.

Biodegradation, Environmental↗
PubMed1994

Evaluation of Epilepsy Expert--a decision support system.

Epilepsy Expert is a decision support system based on the International Classification of Epilepsies and Epileptic Syndromes (1989). The aim of this study was to evaluate the Epilepsy Expert. First the diagnostic performance was validated. This was done in 3 stages: collection of the patient cases, determination of the 'correct diagnoses' and testing the system. How the users perceived the functionality of the system was studied by using an inquiry. Three physicians, experts of epilepsy, from different hospitals were asked to choose 10 patients. In the patient description was a short history, a detailed description of the seizure, EEG findings and their own diagnosis. Next, each expert made a diagnosis of the cases supplied by other experts by using the International Classification of Epilepsies and Epileptic Syndromes. The 'correct diagnosis' (so-called majority agreement) was the diagnosis given by the majority of the experts. The diagnosis of each expert was compared with the 'correct diagnosis'. The diagnoses obtained by the Epilepsy Expert were then compared with the 'correct diagnoses'. In the evaluation the expert physicians agreed on 37% of cases and all 3 disagreed on 17%. A majority agreed on 25 cases, which were used in the evaluation. In these 25 cases the experts' (A,B,C) diagnoses were correct or partly correct in 100, 64, 80% of cases, respectively. The program's diagnoses were correct or partly correct in 80% (module I) and 76% (modules IV and V) of cases. In the evaluation Epilepsy Expert was found to be only partly successful. The main reason for this was the weakness of the international classification. However, the program seems to be very close to the level of the experts. According to this limited inquiry Epilepsy Expert is not suitable for clinical use, because it is, for example, too simple and does not contain enough information.

Adult↗
PubMed1994

Odontogenic myxoma--a radiographic study of 21 tumours.

Radiological features of 21 odontogenic myxomas found in 14 women and 7 men were analysed. Ten of the tumors were unilocular and 11 were multilocular. Unilocular lesions were mostly located in the anterior and multilocular in the posterior areas of the jaws. Intralesional trabeculation was seen in all multilocular but only in 3 unilocular lesions. Because radiological appearance of myxoma may be essentially similar with many other lesions of the jaws careful radiological examination is mandatory for planning of proper treatment.

Adolescent↗
PubMed1993

Function of masticatory system after surgical-orthodontic correction of maxillomandibular discrepancies.

Thirty-two subjects were interviewed about their pre- and post-treatment symptoms of craniomandibular disorders (CMD) and examined for signs of CMD at follow up 2-5 years after surgical-orthodontic treatment for maxillomandibular discrepancies. Symptoms of CMD were among the main reasons for seeking treatment in 31% of the patients. Patients with retrognathic mandibles had significantly more severe symptoms than patients with mandibular prognathism before treatment. After treatment, the severity of subjective symptoms had decreased for the patients as a whole, and significantly in the subjects with originally severe symptoms. Ten subjects out of 12 reported a decrease in the occurrence of headache. The clinical findings of CMD after surgery were usually mild. The importance of occlusal adjustment and rehabilitation as final steps after surgical-orthodontic treatment is stressed.

Adolescent↗
PubMed1991

Penetration of erythromycin into periapical lesions after repeated doses of erythromycin acistrate and erythromycin stearate: a pilot study.

In 26 patients who had undergone apicectomy and extirpation of granulomas (n = 9) or radicular cysts (n = 17), concentrations of erythromycin, 2'-acetyl erythromycin, and their anhydro forms were determined with a novel chemical method in plasma and periapical lesions after at least 2 days of treatment with erythromycin acistrate (EA) (400 mg three times daily, n = 11) or erythromycin stearate (ES) (500 mg three times daily, n = 15). Oral surgery was performed 2 1/2 to 3 hours after the last dose. Blood samples were collected at the time of operation, and immediately before antibiotic treatment, and 1, 2, and 6 hours after treatment. At all time points EA produced at least twice the total antibiotic (2'-acetyl erythromycin plus erythromycin) concentrations in plasma as ES. Erythromycin levels in plasma were at least as high after EA treatment as after ES. In periapical lesions erythromycin concentration after EA was three times higher (1.34 +/- 0.28 micrograms/gm) than after ES treatment (0.40 +/- 0.17 micrograms/gm). Although the total drug concentration in periapical lesions was about the same after EA (2.64 micrograms/ml) and ES (3.41 micrograms/ml), most of the drug recovered after ES was antimicrobially inactive anhydroerythromycin (3.01 micrograms/gm). The concentration of anhydroerythromycin in plasma was approximately the same as that of erythromycin after ES throughout the dose interval. After EA treatment both plasma and the periapical lesion samples contained hardly detectable amounts of anhydroerythromycin. Hence EA has a good bioavailability essential for treatment and prophylaxis of bacterial infections in dentistry.

Adult↗
PubMed1991

Clinical aspects of oral implantology.

During the past few decades the use of implants in dentistry has increased markedly. Endosteal titanium implants are now most commonly used for replacement of single teeth and partial and full dentition. The success rates reported for osseointegrated implants depend on the type of implant and the criteria of success. Results are better for the mandible than the maxilla. Patient selection, careful planning of surgical and prosthetic treatment, and atraumatic, aseptic surgical procedures are essential for successful results. This article reviews various implant methods used in our Department and gives examples of treatment in particular clinical situations.

Adult↗
PubMed1989

Dental infections in association with cerebral infarction in young and middle-aged men.

The association between dental infections and cerebral infarction was investigated in a case-control study involving 40 patients with ischaemic cerebral infarction under the age of 50, and 40 randomly selected community controls matched for sex and age. Poor oral health, as assessed by two indices measuring the severity of infections of teeth and periodontium, or by the presence of subgingival calculus or the presence of suppuration in the gingival pockets, were more common in male patients than in male controls, but no difference was observed in females. If severe dental infections were combined with other probable bacterial infections there were altogether 16 patients (40%) but only two controls (5%) who had suffered from a probable bacterial infection within 1 month or at the time of the stroke or when examined as a control (P less than 0.01). Our results suggest an association between bacterial infection and ischaemic cerebrovascular disease in patients under 50 years of age. Severe chronic dental infection seems to be an important type of infection associated with cerebral infarction in males.

Adolescent↗
PubMed1984

Antithyroid treatment of maternal hyperthyroidism during lactation.

Eleven pregnant women were treated for hyperthyroidism with carbimazole (CZ) and one with propylthiouracil (PTU). Based upon a previous study it was decided that lactation should be permitted if the dose required after delivery did not exceed 15 mg of CZ or 150 mg of PTU. In the patients studied here the daily dose of CZ varied from 5 to 15 mg and that of PTU was 125 mg. TSH was measured in cord blood and in the blood of the newborn infants usually after 2 and 3 weeks of lactation. Serum T4 was measured serially in the infants' blood from day 4 up to 21 day of age, at least. In all instances the TSH concentration in cord blood remained below 45 mU/l the level used in screening for neonatal hypothyroidism. Serum TSH and T4 were all within the appropriate reference limits during the 3 weeks of study with only one exception. In the infant whose mother was treated with PTU the serum T4 measured 5 d after birth was slightly below the lower limit but later returned to normal. Since serum TSH and T4 did not deviate from the reference range in newborn infants during lactation, we conclude that breast-feeding can be permitted if the daily dose of CZ does not exceed 15 mg (or 150 mg of PTU) and if facilities are available for measuring neonatal serum TSH and T4.

Carbimazole↗
PubMed1982

Umbilical cord cortisol and arterial pH levels in spontaneous and induced labors.

The free cortisol concentration in umbilical cord plasma and the pH of umbilical artery blood were determined in 108 full-term fetuses delivered vaginally. Eighty-six of the labors were spontaneous and 22 were induced with oxytocin. The cortisol values correlated significantly with the pH values (r = -.608, P less .001). The cortisol values averaged 0.73 +/- 0.48 mumole/liter in the spontaneous labor group and 0.65 +/0 0.42 mumole/liter in the induced labor group. No statistically significant differences (P greater than .05) in the cortisol and pH values emerged between the groups. The results indicate that the human fetus reacts readily to intrauterine hypoxia and acidosis with endogenic cortisol secretion in both spontaneous and induced labors.

Female↗
PubMedDate not supplied

Cerebral MRI abnormalities and their association with neuropsychiatric manifestations in SLE: a population-based study.

OBJECTIVE: To evaluate the volumetric brain magnetic resonance imaging (MRI) findings in a population-based sample of systemic lupus erythematosus (SLE) patients and to detect a possible relationship between cerebral MRI abnormalities and specific neuropsychiatric (NP) manifestations. METHODS: The study population consisted of patients with SLE (n = 43) in Pirkanmaa Health Care District, Finland and of a sex- and age-stratified reference group from the general population (n = 43). In addition to a clinical neurological investigation, all subjects received a detailed neuropsychological assessment and an MRI study. Volumetric measures of cerebral atrophy as well as T1- and T2-weighted lesions were obtained. SLE activity was assessed by the European Consensus Lupus Activity Measure (ECLAM) index, and accumulated NP abnormalities were measured by the Systemic Lupus International Collaborating Clinics (SLICC) damage index. A cumulative lifetime dose of glucocorticoids was determined from the patientrecords. RESULTS: Compared with controls, SLE patients had increased volumes of both T1- and T2-weighted lesions (p = 0.019 and p<0.0001, respectively) and increased cerebral atrophy (p<0.001). All the measured MRI parameters were statistically significantly higher in NPSLE than in non-NPSLE patients. In SLE patients, cerebral atrophy was associated with cognitive dysfunction, epileptic seizures, and cerebrovascular disease; T1-weighted lesions were associated with epileptic seizures and T2-weighted lesions with cognitive dysfunction. All MRI parameters correlated significantly with the SLICC index but not with the ECLAM index. A positive correlation was found between a cumulative dose of glucocorticoids and cerebral atrophy in SLE patients. CONCLUSION: MRI abnormalities, including brain atrophy and T1- and T2-weighted lesions, are significantly more common in patients with SLE than in the general population and they are related to specific NP manifestations. Our findings also provide support for the organic aetiology of cognitive dysfunction in SLE.

Adult↗
PubMedDate not supplied

Evaluation of Sleep Expert--a computer-aided decision support system for sleep disorders.

Sleep Expert--a medical decision support system--is a prototype program, with knowledge based on the International Classification of Sleep Disorders (1990). The goal of this project was to evaluate Sleep Expert. In the evaluation project the knowledge of the program was first validated. Three physicians, experts in sleep disorders, were asked to choose 10 typical patient cases with sleep disorders, and to write a description. They also made a diagnosis for each case. Next, each expert made a diagnosis of the cases supplied by the other experts. They were not given the original diagnosis. The 'right diagnosis' (so-called majority agreement) was determined from the three diagnoses. Then the diagnosis of each expert was compared with the 'right diagnosis'. Two physicians, not experts in sleep disorders, were asked to make a diagnosis by using Sleep Expert. Compared to the 'right diagnosis' the diagnoses of each user (non-expert physician) were correct to 63 and 70% of cases, which is quite a good result, although it does not reach the level of the expert physicians (> or = 87%). The functionality of Sleep Expert was studied by using a limited inquiry. On the basis of the user inquiry Sleep Expert provided a useful clinical tool for non-experts.

Diagnosis, Computer-Assisted↗