Radioimmunoassay of motilin

A radioimmunoassay method of motilin was developed in our laboratory and was validated in dogs with a platinum monopolar electrode in the duodenum. We confirmed that a bolus infusion of 0.3 M tris-buffer solution or 0.1 N HCl solution in the duodenum produces a significant rise in plasma immunoreactive motilin (IRM) concentrations. This coincided with a marked increase in the percentage of spike potentials on slow waves of the duodenum, similar to phase III of interdigestive myoelectric-activity (MA). A possible relationship between plasma IRM and interdigestive MA of canine duodenum was studied. It was found that cyclic changes occurred in the fasting plasma IRM concentrations in dogs. While the peak motilin concentration was always observed in phase III, the lowest concentration of motilin was found in phase I of interdigestive MA in the duodenum. In dogs with the electrodes in the duodenum and jejunum, the peak IRM concentration did not correlate with phase III of interdigestive MA in the jejunum. A dose of synthetic porcine motilin, 0.06 g/kg/hr, which produced the plasma IRM concentration comparable to the peak fasting motilin concentration, could induce an identical phase III in the duodenum. These observations indicate that there is a relationship between cyclic changes in plasma IRM concentrations and interdigestive MA of the duodenum. It is suggested further that motilin is a hormone which may play an important role in inducing phase III of interdigestive MA in the duodenum.This work was supported by the Gastrointestinal Research Fund at The Genesee Hospital.     

Unusual left ventricular dilatation without functional or biochemical impairment in normotensive extremely overweight Japanese professional sumo wrestlers

To explore the physiologic limit of left ventricular (LV) enlargement, we performed echocardiography and air displacement plethysmography to respectively assess LV dimension and function and the body composition of Japanese professional sumo wrestlers. After excluding subjects with cardiovascular disease, hypertension, plasma brain natriuretic peptide (BNP) > or =17.9 pg/ml, diabetes mellitus, or asthma, 331 subjects (mean +/- SD age, 21.6 +/- 3.7 years; height 179.2 +/- 5.3 cm; weight 1,17.9 +/- 21.5 kg; percent fat, 29.6 +/- 6.6%) were analyzed. LV end-diastolic dimension averaged 58.4 +/- 3.7 mm and was within the generally regarded normal limit (< or =54 mm) in 14.5% of subjects, but was > or =60 mm in 41.1% of subjects. LV septal and posterior wall thicknesses were 10.3 +/- 0.9 and 10.2 +/- 0.9 mm, respectively. Peak E- and A-wave velocities, E/A ratio, LV fractional shortening, and BNP were 96 +/- 16 and 51 +/- 13 cm/s, 2.0 +/- 0.7, 33.5 +/- 4.5%, and 3.1 +/- 3.7 pg/ml, respectively. LV end-diastolic dimension was not correlated with these indexes of LV function or with plasma BNP levels, but was significantly correlated with height, weight, body surface area, fat-free mass, and fat mass. These results show that among very large, highly trained, professional athletes, LV end-diastolic dimension frequently exceeds the traditionally accepted upper limit of normal for the general population. This increase in LV end-diastolic dimension may thus represent an extreme example of the physiologic adaptation of the athlete's heart.     

Changes in calcium homeostasis in acromegaly treated by pituitary adenomectomy

Patients with acromegaly have alterations in mineral metabolism. To determine the effect of correction of excess GH secretion on calcium metabolism, we studied 12 acromegalic patients before and 3-4 weeks after pituitary adenomectomy. Treatment of acromegaly resulted in significant decreases in both serum calcium [from 9.3 +/- 0.2 to 8.7 +/- 0.1 mg/dl (mean +/- SEM); P less than 0.01] and urinary calcium excretion (from 200 +/- 24 to 88 +/- 12 mg/24 h; P less than 0.0002). Serum phosphate also decreased significantly (P less than 0.01) from 4.8 +/- 0.2 to 4.3 +/- 0.2 mg/dl. Both serum immunoreactive PTH and calcitonin levels were normal initially and did not change after surgery. The mean serum 25-hydroxyvitamin D (25OHD) level was significantly (P less than 0.01) lower and the 1,25-dihydroxyvitamin D [1,25-(OH)2D] level was significantly (P less than 0.0001) higher in acromegaly compared with measurements in 25 normal subjects. After surgery, the serum 25OHD level did not change; however, the serum 1,25-(OH)2D concentration fell significantly (P less than 0.0001) from 60 +/- 4 to 43 +/- 2 pg/ml. A positive correlation was found between the decrements in urinary calcium excretion and the serum 1,25-(OH)2D level when the comparison was made between the decrements as percentages of pretreatment values (r = 0.64; P less than 0.05). The accumulated data suggest that the hypercalciuria in acromegaly might be due to intestinal calcium hyperabsorption, which could be attributed to the elevated circulating 1,25-(OH)2D level. Excessive GH secretion might stimulate the production of 1,25-(OH)2D and might also directly stimulate calcium absorption.     

Effect of radioactivity outside the field of view on image quality of dedicated breast positron emission tomography: preliminary phantom and clinical studies

Annals of Nuclear Medicine - Semi-quantitative positron emission tomography (PET) values, such as the maximum standardized uptake value (SUVmax), are widely used to identify malignant lesions and...     

Identification of an oncogenic form of the thrombopoietin receptor MPL using retrovirus-mediated gene transfer

Thrombopoietin and its receptor (MPL) are important regulators of megakaryopoiesis. We have identified an activating mutation of MPL using a combination of a retrovirus-mediated gene transfer and polymerase chain reaction-driven random mutagenesis. This point mutation causes a single amino acid substitution from Ser498 to Asn498 in the transmembrane region and abrogates factor-dependency of all interleukin-3-dependent cell lines tested. Murine interleukin-3- dependent Ba/F3 cells expressing the mutated but not the normal form of MPL were tumorigenic when transduced into syngeneic mice. Analysis of intracellular signaling pathways indicated that the mutant MPL protein constitutively activated two distinct signaling pathways, SHC-Raf-MAPK and JAK2-STAT3/STAT5.     

Evaluation of the depth score of type V pit patterns in crypt orifices of colorectal neoplastic lesions

Background We developed and evaluated the clinical usefulness of a scoring system that subclassified type Vi pit patterns. Methods We studied 119 colon cancer lesions (pTis, n = 26; pT1, n = 93) and 22 tubular adenoma lesions with severe atypia in which a type Vi pit pattern was visible under a stereomicroscope. Four type Vi pit pattern formation appearances (existing pits, marginal irregularities of the gland duct, narrowing of the gland duct lumen, and unclear outline of the gland duct) were defined, and the relationship between each appearance and the invasive depth of the cancer was evaluated. Results When the four type Vi pit pattern appearances were considered in a logistic regression analysis, the odds of a more invasive submucosal cancer were significantly increased by the appearance of marginal irregularities, a narrowed lumen, and an unclear outline. In the logistic regression analysis results, when 0.63 was used as the cutoff score for prediction of a more invasive submucosal cancer, 80 cases in the less invasive group were classified correctly (specificity, 1.0), whereas 53 (86.9%) of the 61 cases in the more invasive group were classified correctly (sensitivity, 0.869). Conclusions It is important first to understand the usability and limitations of objective scoring of type V pit pattern findings and then to apply this score to the determination of cancer depth in order to accurately identify lesions suitable for endoscopic treatment.     

Serum antibodies to carbonic anhydrase IV in patients with autoimmune pancreatitis

BACKGROUND AND AIMS: Serum antibodies to carbonic anhydrase (CA) II have been reported in patients with autoimmune pancreatitis (AIP) and Sjogren's syndrome (SjS). However, their significance in the pathogenesis of these diseases is controversial. The aim of this study was to identify serum antibodies to CA isozymes, which are expressed in ductal cells of the pancreas. METHODS: Recombinant proteins of human CAs IV, IX, and XII were obtained using a bacterial expression system, and five CA IV peptides with theoretically high antigenicity were synthesised. Western blotting and enzyme linked immunosorbent assay (ELISA) were used to detect serum antibodies to the CA isozymes. RESULTS: The first screening analysis by western blot showed serum antibodies to CA IV among three CA isozymes in patients with idiopathic chronic pancreatitis, including AIP patients. Further analysis by ELISA showed a significantly increased prevalence of serum antibodies to the truncated CA IV protein and the CA IV synthetic peptide (LGS LTT PTC DEK VVW TVF REP I) in patients with definite AIP (4/15 and 6/20, respectively; p<0.01), probable AIP (6/14 and 3/14; p<0.02), and SjS (9/20 and 8/40; p<0.001) compared with normal controls (0/26). There was no significant difference in the antibody prevalence rates between normal controls and patients with alcoholic chronic pancreatitis (2/15 in each) or pancreatic cancer (2/14 and 1/14, respectively). The presence of serum antibodies to the CA IV peptide showed significant correlations with serum gamma-globulin and IgG levels in AIP patients. CONCLUSIONS: These findings suggest that CA IV may be a target antigen that is commonly expressed in epithelial cells of specific tissues involved in AIP and its related diseases.     

Optimal relaxation parameters of dynamic row-action maximum likelihood algorithm and post-smoothing filter for image reconstruction of dedicated breast PET

Annals of Nuclear Medicine - This study aimed to determine the optimal β value of the relaxation control parameter and the post-smoothing filter in the list-mode dynamic row-action maximum...     

Effective and selective stretching of the medial head of the gastrocnemius

Muscle injury frequently occurs in the medial head of the gastrocnemius (MG), and stretching is used for treatment. However, there are no studies based on anatomical considerations and biomechanics. This study therefore examined the macroscopic anatomical structure of the triceps surae muscle to design an effective and selective MG stretching method, before quantitatively verifying that method by ultrasonography. The macroscopic anatomy was analyzed in 16 Japanese cadavers (25 legs). Based on the anatomical findings and the arrangement of fascicles in the MG, we concluded that ankle inversion might be advantageous for selective stretching of the tendon fiber bundles into which the MG inserts. We devised a method in which the limb was initially positioned with the knee joint in extension and the ankle joint in plantar flexion. Then, the ankle was dorsiflexed and inverted. The proposed method was compared with standard stretching and verified by ultrasonography in eight healthy adult males. This method effectively and selectively stretched the MG, producing a significantly decreased pennation angle and increased muscle fiber length. This method may be beneficial for preventing future injuries and may enhance the effect of therapy on the MG.