Feeding behavior in rats subjected to gastrectomy or gastric bypass surgery.

BACKGROUND/AIM: Gastric bypass (GB) is usually designed to restrict food intake and to induce malabsorption. Gastric hormones have been thought to play a role in the regulation of food intake and body weight. The aim of the present study was to analyze feeding behavior after total gastrectomy (Gx) or GB in rats. METHODS: Animals were subjected to Gx, GB, or sham operations. Eating and drinking behaviors after surgeries were assessed by a comprehensive laboratory animal monitoring system. Gastric hormones were measured by radioimmunoassay and energy density in feces by adiabatic bomb calorimeter. RESULTS: Compared with sham operation, both Gx and GB reduced the body weight as measured during 3-8 weeks postoperatively, which was associated with increased energy expenditure per 100 g body weight. Daily accumulated food intake and meal size (during nighttime) were reduced following Gx, but not GB. The water intake (during daytime) was increased after Gx and GB. The energy density in feces was unchanged. Serum concentrations of ghrelin, obestatin, leptin, gastrin, and pancreastatin were greatly reduced after Gx. CONCLUSIONS: Control of food intake and meal size was independent of the food reservoir function of the stomach. Surgical depletion of gastric hormones is associated with reduced meal size, but increased water intake.

An ion exchange chromatography and radioimmunoassay procedure for measuring opioid peptides and substance P.

The measurements of peptides of the enkephalin, dynorphin and substance P systems is complicated by the number of possible precursor fragments and degradation products that might cross-react with the antisera. By using an ion-exchanger step before radioimmunoassay we can reduce the possibility that observed peptide levels are due to precursors or metabolites. The ion-exchanger method runs with good recovery and its main advantage is that many samples can be run in parallel. The recovery from the ion-exchanger was similar using two different homogenizing media, whereas the measured endogenous levels of [Met] and [Leu]enkephalin were 3-4 fold higher with 1M acetic acid than when a 1:1 MeOH/HCl mixture was used for tissue extraction.

A comparison of the pharmacokinetic properties of three estradiol esters.

In order to assess the pharmacokinetics properties of estradiol cypionate, valerate and benzoate, the daily plasma levels of estradiol and estrone were analysed in groups of 10, 9 and 10 subjects, respectively, before and during 3 weeks after the intramuscular administration of a single dose of 5.0 mg in 1.0 ml arachis oil. In order to minimize the contribution of endogenous estrogens to the plasma levels, all subjects were receiving a combined oral contraceptive consisting of levonorgestrel (150 micrograms) and ethinyl estradiol (30 micrograms) for three months prior to the study and during the study period. The administration of estradiol cypionate gave significantly lower peak levels of estradiol and estrone than that of the valerate and benzoate. Peak plasma levels of estradiol and estrone were reached in approximately 4 days following the administration of estradiol cypionate and in a significantly shorter time (approximately 2 days) following the administration of both the valerate and benzoate. One hour after the injection of the esters, the average percentage increases in plasma estradiol and estrone levels were significantly higher in the valerate and benzoate groups compared to the subjects receiving estradiol cypionate. The average duration of elevated estrogen levels was shortest in the benzoate group (4-5 days) followed by the valerate (7-8 days) and cypionate (approximately 11 days). In none of the subjects studied were elevated estradiol and/or estrone levels encountered 2 weeks after the injection of the various esters. The data suggests that among the three esters studied, the valerate provides the most predictable pharmacokinetic behaviour.

PIP: Pharmacokinetic properties of 3 natural estradiol esters, (estradiol cypionate, valerate, and benzoate), were assessed by assaying daily plasma levels of estradiol and estrone in groups of 10, 9, and 10 subjects, respectively, before and during 3 weeks of intramuscular administration of a single dose of 5 mg of one of the estradiols in oil. Subjects were given a combined oral contraceptive 3 months before and during the study to minimize the contribution of endogenous estrogens to the plasma levels. Estradiol cypionate yielded significantly lower peak estradiol and estrone levels than did valerate and benzoate esters. Estradiol and estrone levels both reached peak levels about 4 days after the injection of the cypionate ester and about 2 days after administration of the valerate and benzoate esters. Estrogens were elevated for the shortest time (4-5 days) with the benzoate ester, which was followed by the valerate (7-8) and the cypionate (about 11 days). After 2 weeks, no subjects showed elevated estradiol or estrone levels. It is concluded therefore that the valerate ester has the most predictable pharmacokinetics and would be most suitable for use in a contraceptive formulation.

TMD in patients with primary Sjögren syndrome: a comparison with temporomandibular clinic cases and controls.

AIMS: The aim of this study was to investigate the prevalence of temporomandibular disorders (TMD) in patients with primary Sjögren syndrome (1 degree SS), analyze the impact of the disease on mandibular function, and assess psychosocial distress. METHODS: Sixty-three subjects, 60 women and 3 men, participated in the study; 21 1 degree SS patients were compared with age-matched and gender-matched groups of TMD subjects and controls. Patients were examined according to the Research Diagnostic Criteria for Temporomandibular Disorders. RESULTS: Results showed that the subjective, clinical, and radiographic signs of TMD are not more common in patients with 1 degree SS than in controls. The impact of the autoimmune disease on mandibular function, e.g., speech and chewing ability, revealed limitations in oral functioning similar to those in patients with TMD pain. CONCLUSION: Both 1 degree SS and chronic TMD may be associated with appreciable physical discomfort and psychosocial dysfunction. However, the underlying mechanisms of the oral dysfunction of 1 degree SS and TMD are quite different and essentially unrelated.

Dose contributions to the Swedish population from oral radiography.

The purpose of the present investigation was to elucidate some factors which may influence the absorbed doses to organs of special interest, to determine the energy imparted (epsilon) and the effective dose equivalent (HE) from intraoral radiography, to estimate the collective effective dose equivalent (SE) to the Swedish population from oral radiography and to discuss these results regarding the biological effect of oral radiography on the Swedish population. The absorbed doses were found to be small from intraoral radiography (IR), with a reduction by a factor of about 50 to many organs since the 1960s. The epsilon to the patient from IR (20 exposures, 65 kVp, D-film) was 10 mJ with a circular (55 mm in diameter) and 6 mJ with a rectangular collimator (35 mm X 44 mm). For one bitewing the corresponding values were 0.4 mJ and 0.3 mJ, respectively. The mean value of epsilon for an ordinary bitewing examination in Sweden was 0.48 mJ. Energy imparted from IR was totally 5,500 J to the Swedish population. This corresponds to some per cent of the mean value of the annual natural irradiation. The use of film in speed group E reduces the energy imparted by 40 per cent. From panoramic radiography (PR) and lateral cephalographic radiography (CR) the mean values in Sweden were 0.5 mJ per examination. PR and CR imparted 56 J to the population. HE was calculated for IR and was found to be 0.23 mSv (20 exposures, D-film, circular collimator) and 0.14 mSv for the rectangular collimator, which corresponds to 12 and 7 mu Sv per intraoral film, respectively. The risk from IR, PR and CR to the population can be assessed by risk factors from the literature and estimated both from the sum of epsilon and from the sum of HE. Proceeding from the sum of epsilon and transforming to HE by dividing the body weight the collective effective dose equivalent was 79 manSv (IR) and 1 manSv (PR and CR). Proceeding from the calculated value of HE for IR would give 190 manSv. The risk of fatal cancer thus theoretically calculated would be between 1-3 cases. The magnitude of epsilon as well as HE is so low that it seems to be a very favourable ratio between benefit and risk for IR, when such examinations are indicated.

Collective doses to the Swedish population from panoramic radiography and lateral cephalography.

A questionnaire was sent to all dental offices in Sweden equipped with panoramic and cephalographic x-ray units. Data were obtained for estimating the energy imparted from panoramic radiography and lateral cephalography during 1984 to the Swedish population. There were two units with intraorally placed focus among the 121 panoramic units studied. Approximately half of the panoramic radiographs, totally 79,000, were exposed on individuals younger than 20 years of age. Ninety-three cephalographic units were used to expose 40,000 lateral cephalograms, of which 10 per cent were exposed on children less than 10 years old and 12 per cent on adults. The energy imparted was estimated using the collected data, relative depth dose values and conversion factors from the literature. Mean energy imparted per panoramic examination was 0.50 mJ, and per cephalogram 0.43 mJ. From the panoramic and cephalographic examinations the energy imparted to the Swedish population was 40 J and 17 J, respectively. The corresponding collective effective dose equivalent to the population would be 0.75 manSv and 0.43 manSv, respectively. As a comparison, the collective effective dose equivalent from the annual natural irradiation including radon irradiation from dwellings is about 6.8.10(4) manSv.

Dental health of Finnish immigrants in Sweden.

Though foreign citizens today constitute 5% of the population of Sweden, very few attempts have been made to assess the types and amount of dental disease and treatment needed by different immigrant populations. A survey, including a clinical and radiographic examination for dental health, was carried out on an age-stratified probability sample of 170 Finnish citizens, 20-80 years old, living in the community of Huddinge, a suburb of Stockholm. The study showed that in the age group 20-29 years 90% and in the older age groups 60% of the dentate subjects had caries. All of them had gingivitis. 20% of subjects aged 20 to 39 years and 54% of those aged 40 and over had the diagnosis parodontitis gravis, indicating a time-consuming need for periodontal treatment. Periapical lesions were frequent and more than half of the root fillings present were poor. This study indicates poorer dental health and a greater need for dental treatment in this group of Finnish immigrants than in Swedish populations.

Radiation absorbed doses in cephalography.

Radiation absorbed doses to different organs in the head and neck region in lateral (LAT) and postero-anterior (PA) cephalography were investigated. The doses were measured by thermoluminescence dosimeters (TLD) on a tissue equivalent phantom head. Lanthanide screens in speed group 4 were used at 90 and 85 kVp. A near-focus aluminium dodger was used and the radiation beam was collimated strictly to the face. The maximum entrance dose from LAT was 0.25 mGy and 0.42 mGy from a PA exposure. The doses to the salivary glands ranged between 0.2 and 0.02 mGy at LAT and between 0.15 and 0.04 mGy at PA exposures. The average thyroid gland dose without any shielding was 0.11 mGy (LAT) and 0.06 mGy (PA). When a dodger was used the dose was reduced to 0.07 mGy (LAT). If the thyroid gland was shielded off, the dose was further reduced to 0.01 mGy and if the thyroid region was collimated out of the primary radiation field the dose was reduced to only 0.005 mGy.

Absorbed doses at varying tube voltage in lateral cephalography.

Absorbed doses in organs of special interest from lateral cephalography were measured by thermoluminescence dosimetry in a tissue equivalent phantom head. The radiographic examination was performed in a standardized manner by using a carefully collimated radiation field and a near-focus dodger. The actual tube voltages ranged from 63-127 kVp. The absorbed dose was described as a function of tube voltage. In all measurement sites the absorbed dose decreased with increasing tube voltage. This reduction was most obvious in the low tube voltage range. From the results a lowest recommendable tube voltage was given for the different measurement sites varying from approximately 75 kVp (thyroid region) to approximately 100 kVp (parotid region). A high tube voltage was found to be important for a low absorbed dose in different organs in lateral cephalography.

Collective dose to the Swedish population from intraoral radiography.

In 1984 the Swedish National Institute of Radiation Protection (SSI) undertook an investigation (KAST) of 400 randomly selected dental offices to check the extent to which the new rules and recommendations concerning radiation protection (SSI 1978, 1980) were applied. Data for calculation of the energy imparted per bitewing examination of an adult were available. The information obtained was utilized for estimating the collective dose in Sweden from intraoral radiography. The mean value of the energy imparted from an ordinary bitewing examination was 0.48 mJ. The quotient between the sum of all imparted energy during 1984, 5,519 J, and the number of inhabitants in that year was 0.66 mJ. This corresponds to 1.5 ordinary bitewing examinations per individual in Sweden. The collective effective dose equivalent is 79 manSv after transformation from the total energy imparted. The average energy imparted from the annual natural irradiation in Sweden is 100 mJ, with variations between 35 and 350 mJ, giving totally to the population 830,000 J. The dose contribution from intraoral radiography is thus considered of minor importance when taking into account the variations of the natural irradiation as well as the benefit of the diagnostic gain in dentistry and the enhancement of public dental health.

Effective dose equivalent from intraoral radiography.

By means of available data of mean organ doses from intraoral radiography the effective dose equivalent from dental radiography was calculated. The dose values used correspond to 65 kVp, 0.2 m FSD and 20 exposures with film in speed group D. The effective dose equivalent was calculated for circular (55 mm diameter) as well as rectangular collimator (35 mm X 44 mm) and amounted to 0.23 and 0.14 mSv, respectively. In comparison with the annual natural radiation the corresponding time would be 6 and 3 weeks, respectively. Following the definition of the effective dose equivalent by ICRP (1977) it was found that the most radiosensitive organs contributed 20-25 per cent of the total effective dose equivalent. The organs with the highest weighting factors thus received very small or negligible dose equivalents. The calculation necessitates a detailed knowledge of the absorbed doses and the weighting factors, which made the application for dental radiography somewhat uncertain. The concept of energy imparted might be a more direct measure to compare the risk from different examinations in dental radiography.

Energy imparted from intraoral radiography.

During the recent decade the equipment for dental radiography in Sweden has been standardized by the Swedish National Institute for Radiation Protection. The aim of this study was to experimentally determine the energy imparted to a phantom from a full survey with 20 intraoral films as well as from a single bitewing projection, using this standardized technique. Thermoluminescence dosimeters in predetermined volume elements of an anatomically formed tissue equivalent Alderson-phantom were irradiated (65 k Vp) using both a rectangular and a circular collimator of 0.2 m FSD. Exposure times fitted to film in speed group D were used. The energy imparted was determined from the integrated absorbed doses in the volume elements as well as calculated using published depth dose data. The energy imparted was found to be 9.6 mJ (circular collimator) and 5.9 mJ (rectangular collimator) for the full survey. For the single bitewing exposure the energy imparted was 0.42 mJ (circular collimator) and 0.29 mJ (rectangular collimator). With the rectangular collimator and film in speed group D the energy imparted from a full survey will correspond approximately to two weeks of environmental irradiation. With more sensitive film in speed group E the energy imparted would further be reduced by 40 per cent with retained diagnostic information.

Absorbed doses from intraoral radiography with special emphasis on collimator dimensions.

Thermoluminescence dosimeters were used in a phantom head and on patients to measure the absorbed dose to organs of special interest from full surveys with intraoral films (20 exposures) and single bitewing exposures. Two x-ray machines were used, operating at 65 kVp. The apertures of the circular tube collimators had diameters of 55 mm and 48 mm. Rectangular (35 mm X 44 mm) tube collimators were also used. The distance from the x-ray focus to the open end of the collimators (FSD) was 0.20 and 0.35 m. Exposure values for Kodak Ultra-Speed film (speed group D) were used. The maximum skin dose measured from the full surveys decreased by 25 per cent on changing from the circular to the rectangular apertures. Using 0.35 m FSD and rectangular collimator the maximum skin dose was 13 mGy. The absorbed doses to the salivary glands and the thyroid gland were significantly reduced on changing from circular to rectangular apertures. The doses in the central part of the parotid and the thyroid glands were then 0.5 and 0.12 mGy, respectively, from a full survey with 20 intraoral films. With a leaded shield the thyroid dose was reduced to 0.05 mGy. All dose values could be further reduced by 40 per cent by using Kodak Ektaspeed film (speed group E).

Periodontal conditions in 70-year-old women with osteoporosis.

The aim of the present study was to examine the periodontal conditions in an age cohort of 70-year-old women and compare an osteoporosis group with a control group with normal bone mineral density. 210 women 70 years old and randomly sampled from the population register of the community of Linköping were examined. Bone mineral density (BMD) of the hip was measured by dual energy X-ray absorptiometry. 19 women were diagnosed with osteoporosis (BMD below 0.640 g/cm2 in total hip). 15 of them accepted to participate in the study. As a control group 21 women with normal bone mineral density (BMD exceeding 0.881 g/cm2) were randomly selected from the initial population. The clinical examination included registration of the number of remaining teeth, dental plaque and periodontal conditions. The radiographic examination included a dental panorama and vertical bite-wing radiographs. The subjects also answered a questionnaire about their general health, age at menopause, concurrent medication, smoking and oral hygiene habits. The results from this study showed no statistically significant differences in gingival bleeding, probing pocket depths, gingival recession and marginal bone level between the women with osteoporosis and the women with normal bone mineral density. In conclusion, the present randomly selected and controlled study of osteoporotic and non-osteoporotic women, showed no statistically significant differences in periodontal conditions or marginal bone level. As periodontitis as well as osteoporosis are associated with age, our study of a well-defined age cohort is of interest, but the results should be interpreted with caution since the compared groups are small.

Radiation absorbed doses at radiographic examination of third molars.

The radiation absorbed doses to critical organs, i.e. the thyroid and salivary glands and the gonadal region, were measured at radiographic examination of third molars. A tissue equivalent phantom was used together with ionization chamber detectors and TLDs. In the maxilla three, and in the mandible four different projections were used; also an extraoral lateral view. The greatest thyroid dose, 35 muGy, came from a mandibular disto-oblique projection with the circular tube collimator and Ultra-Speed film. the thyroid dose from an extraoral lateral view with high sensitivity screens was 3.7 muGy. The doses in different parts of the parotid gland from the disto-oblique mandibular projection with Ultra-Speed film ranged between 2.65 and 0.052 mGy. The corresponding doses in the submandibular gland were 1.74 mGy beneath the mandible and 0.458 mGy in the fovea. A rectangular tube collimator reduced the doses by approximately 50%. the Ekta-Speed film required approximately 40% lower exposure than the Ultra-Speed film. Without shielding the gonadal doses from a complete examination of four third molars were of the same order of magnitude as from a full survey with intraoral films, i.e. 3-7 muGy. A horizontal radiation shield reduced the thyroid doses by between 12 and 46% and the gonadal doses by between 50 and 95%. The reduction effect from the shield was relatively greater when using the larger aperture of the tube collimator. Combinations of leaded aprons and soft leaded collars reduced the thyroid doses by between 15 and 42% and the gonadal doses by two orders of magnitude.

Radiation shielding in dental radiography.

The protective effect in the thyroid region from different types of radiation shielding at intraoral radiography has been studied as well as the reduction of the absorbed dose to the sternal and the gonadal regions. The shielding tested were the different types of leaded aprons, of which three had an attached leaded collar and the other two were used in combination with separate soft leaded collars. Furthermore one of the soft leaded collars and an unflexible horizontal leaded shield were tested separately. Two dental x-ray machines of 60 and 65 kVp with rectangular and circular tube collimators were used. The exposure times corresponded to speed group E film. The absorbed doses were measured with two ionization chambers. No significant difference in the protective effect in the thyroid gland could be found between the different types of radiation shieldings. There was a dose reduction by approximately a factor of 2 to the thyroid region down to 0.08 mGy per full survey using parallelling technique, and below 0.001 mGy per single bitewing exposure. The shielding reduced the thyroid dose using bisecting-angle technique by a factor of 5 down to 0.15 mGy per full survey (20 exposures). In the sternal region the combinations of apron and collar reduced the absorbed dose from a full survey to below 2 microGy compared with 18 microGy (parallelling) and 31 microGy (bisecting-angle) without any shielding. With the horizontal leaded shield a reduction by a factor of 6 was obtained, but no significant sternal dose reduction could be detected from the soft collar alone. The gonadal dose could be reduced by a factor of 10 with the horizontal leaded shield, parallelling technique and circular collimator. Using leaded aprons the gonadal was approximately one per cent of the dose without any shielding, i.e. below 0.01 microGy per single intraoral exposure.

Feeding behavior and body weight development: lessons from rats subjected to gastric bypass surgery or high-fat diet.

Weight loss treatments include diets, drugs, physical training, and surgery, namely bariatric or obesity surgery. The current standard for bariatric surgery is gastric bypass. There are common beliefs that gastric bypass induces body weight loss because of a reduced food intake and that high-fat diet induces overweight and obesity because of overnutrition. The principal aim of the studies on rats summarized herein was to better understand the physiological mechanisms by which gastric bypass achieves body weight loss and by which high-fat diet induces obesity. The results indicated that gastric bypass efficiently reduced body weight, particularly the fat compartment, which was unlikely to be caused by early satiety, reduced food intake or malabsorption, and that large meal size, but not overnutrition, was mainly responsible for high-fat diet-induced obesity. It was unclear whether gastric ghrelin, obestatin and/or amine in the A-like cells were involved in this context.

Frequency of bilateral temporomandibular joint disc displacement in patients with unilateral symptoms: a 5-year follow-up of the asymptomatic joint. A clinical and arthrotomographic study.

Bilateral arthrotomography was performed in 50 consecutive patients with unilateral symptoms of disc displacement to evaluate the frequency of temporomandibular joint disc displacement in asymptomatic joints. Using well-defined clinical criteria, there were no false-positive findings of either reducing or non-reducing discs. On the other hand, a risk of false-negative diagnosis of non-reducing disc was apparent. Sixty per cent of the patients had a non-reducing displaced disc in the asymptomatic joint. Most of these patients could recall a previous spell of discomfort from this joint. Severe or moderate deformation had taken place in non-reducing discs, while reducing discs were normal in shape or had, at most, a thickening of the posterior band. The duration of symptoms was significantly correlated with the degree of deformation in the symptomatic joints (P less than 0.01). Perforation was statistically, significantly correlated with disc deformation and, in symptomatic joints, hard tissue changes. Fifty-seven per cent of the asymptomatic joints with displaced discs developed pain following the onset of symptoms from the contralateral side, most within 2 years. Less than half of them were free of pain at the end of the 5 year follow-up period. In view of this tendency for an asymptomatic joint with a displaced disc to subsequently develop pain refractory to treatment, such a joint must be considered a weakened link in the craniomandibular system, vulnerable to changes in mandibular function such as, for instance, displacement of the disc on the contralateral side.

Angiotensin II in rat brain comigrates with authentic angiotensin II in high pressure liquid chromatography.

Indirect evidence has implicated a role for central angiotensin II in blood pressure control. To answer directly the question of whether angiotensin II exists in the brain, independent of blood-borne angiotensin, and to quantify the amounts in different parts of the central nervous system, a sensitive radioimmunoassay was used to measure extracts of male adult rat brain hypothalamus and cortex after purification with high pressure liquid chromatography with a high recovery. The fractions coeluted with authentic angiotensin. Rats were nephrectomized bilaterally, and 24 hours later the brains were extracted in acetic acid and boiled. SepPak C-18 purification preceded reverse phase high pressure liquid chromatography. High pressure liquid chromatography revealed two peaks, one which comigrated precisely with [Ile5] angiotensin II, and another smaller peak which overlapped with [Ile5] angiotensin III. The highest levels were found in the hypothalamus (125 pg/g tissue), pituitary (190 pg/g tissue), spinal cord (199 pg/g tissue), and lower levels were found in cortex (60 pg/g tissue). The results demonstrate that the antibody which was previously used in the immunocytochemical localization of angiotensin in the hypothalamus detects authentic angiotensins. However, the study did not depend on just one antibody. A second antibody which we developed gave the same results. Molecular sieving using Sephadex G-25 with acetic acid revealed a distinct peak in the 1000 MW range and a smaller, higher molecular weight peak which needs further investigation. Spontaneously hypertensive rats did not have higher concentrations of hypothalamic angiotensin II than normotensive rats.(ABSTRACT TRUNCATED AT 250 WORDS)

Observer performance in the assessment of periapical pathology: a comparison of panoramic with periapical radiography.

Observer performance in the assessment of the periapical pathology from panoramic and periapical radiography was examined. Five endodontists, five general practitioners and five oral radiologists were asked to assess the periapical status of 117 teeth. The observers assessed the panoramic and periapical radiographs of the teeth, which were evenly distributed throughout the jaws with a 50% probability that either an osteolytic or sclerotic lesion was present. The results of the comparison between panoramic and periapical radiography were influenced by the selection of observers. When the oral radiologists acted as observers, the mean P(A) value for periapical radiography was higher than for panoramic radiography (P less than 0.001), resulting in periapical radiography presenting a higher overall diagnostic accuracy than panoramic radiography for all 15 observers (P less than 0.01). There was, however, no difference between panoramic and periapical radiography when the two groups of endodontists and general practitioners acted as observers. The comparison of the three groups of observers showed no difference between their diagnostic accuracy when assessing panoramic radiographs. With periapical radiography, the oral radiologists demonstrated a higher diagnostic accuracy than the endodontists (P less than 0.05). The observers in each group with the highest diagnostic accuracy also had the highest intra-observer agreement. The mean intra-observer agreement of the five general practitioners was higher than those of the other two groups of observers for panoramic radiography. For periapical radiography, the mean agreement rates of the groups were comparable.