Magnetic resonance images and histology of the spheno-occipital synchondrosis in young monkeys (Macaca fuscata)

Magnetic resonance images and the histology of spheno-occipital synchondrosis were examined in young monkeys in order to compare the magnetic resonance images with their histologic observations. In serial magnetics resonance images of posterior cranial base, the spheno-occipital synchondrosis showed a low signal zone with unclear boundaries, running through the posterior cranial base perpendicularly to the clivus. The zone was always interposed between nonsignal zones. These observations were the same as those in young juvenile human beings. The histologic sections also revealed that the low signal zone was really the spheno-occipital synchondrosis, which consisted of hyaline cartilage and that the nonsignal zones were bone tissues. The chondroblasts in the spheno-occipital synchondrosis were arranged bipolarly. Intense alkaline phosphatase activity was located in the areas along the bone. Tetracycline labeling was also noticed in the bone formed in the endochondral ossification. These results suggest that magnetic resonance imaging enables us to observe the spheno-occipital synchondrosis in the posterior cranial base and also to elucidate its influences on the growth of maxilla and mandible in the future.

Separation of 1-phenyl-3-methyl-5-pyrazolone derivatives of monosaccharides by capillary electrochromatography

1-Phenyl-3-methyl-5-pyrazolone (PMP) derivatives of component monosaccharides in glycoproteins (fucose, galactose, mannose, N-acetylgalactosamine and N-acetylglucosamine) and epimeric aldopentoses (arabinose, lyxose, ribose and xylose) were well separated from each other by capillary electrochromatography on a Hypersil ODS column with a mixture of 50 mM N-(2-hydroxyethyl)piperazine-2'-(2-ethanesulfonic acid) buffer, pH 6.0 to approximately 6.3, and acetonitrile (2.2:1 v/v) as eluent. The elution of these compounds showed relatively strong dependence on the pH and concentration of the buffer salts contained in the eluent, as compared to the elution by pressure-driven high-performance liquid chromatography (HPLC) on the same stationary phase, but separation of PMP-monosaccharides was better than that by HPLC. Retention times of PMP-monosaccharides were highly reproducible with a relative standard deviation (RSD) of approximately 0.6%, and quantification with an RSD less than 5% could be achieved using 3-O-methylglucose as an internal standard.

Comparison of laboratory test results before and after surgical removal of heartworms in dogs with vena caval syndrome

OBJECTIVE

To compare results of laboratory tests in dogs with vena caval syndrome before and after surgical removal of heartworms.

DESIGN

Longitudinal uncontrolled clinical trial.

ANIMALS

51 dogs with vena caval syndrome.

PROCEDURE

Heartworms were removed from the area of the tricuspid valve and pulmonary arteries via venotomy and by use of flexible alligator forceps. Blood samples were obtained before and 10 days after removal of heartworms. Red and white blood cell counts were determined, using an automated cell counter. Biochemical tests were performed, using a dry chemical method.

RESULTS

45 dogs survived the procedure, and 6 died or were euthanatized after surgical treatment. After surgery, RBC count and total protein, albumin, calcium, and sodium concentrations increased, and total bilirubin, ammonia, BUN, creatinine, uric acid, and potassium concentrations decreased in dogs that survived. Creatine kinase, L-lactate dehydrogenase, and amylase activities decreased, whereas alkaline phosphatase and gamma-glutamyltransferase activities and total cholesterol concentration increased. Alanine transaminase activity decreased in 27 dogs but increased in 3 dogs. Changes in test results in dogs that did not survive. Significant differences were found in RBC count, gamma-glutamyltransferase activity, and total protein, total cholesterol, BUN, and total bilirubin concentrations before and after removal of heartworms.

CLINICAL IMPLICATIONS

Hepatic and renal functions improve rapidly after surgical removal of heartworms, presumably because general and pulmonary circulation is normalized. However, cholestasis may develop, and dogs that survive may need additional treatment to preserve hepatic function.

Changes in microsomal membrane phospholipids and fatty acids and in activities of membrane-bound enzyme in diabetic rat heart

Diabetes mellitus is associated with alterations in lipid metabolism and cardiac dysfunction despite an absence of coronary arteriosclerotic changes. To investigate mechanisms of cardiac dysfunction in diabetic cardiomyopathy, we studied the relation between activities of membrane-bound enzymes and surrounding phospholipids in rats with diabetes induced with a single intravenous injection of streptozotocin (65 mg/kg). We found that total phospholipid content of sarcoplasmic reticulum membrane increased significantly 8 weeks after treatment with streptozotocin owing to increases in phosphatidylcholine and phosphatidylethanolamine, a decrease in arachidonic acid, and an increase in docosahexaenoic acid in the early stage of diabetes. Sarcolemmal Na+/K(+)-ATPase activity and the number of receptors decreased in isolated cardiomyocytes of diabetic rats 8 weeks after streptozotocin administration. The Ca2+ uptake of both sarcoplasmic reticulum and mitochondria decreased simultaneously in permeabilized, isolated cardiomyocytes from diabetic rats. The depression of membrane-bound enzyme activities was correlated with alterations in phospholipids, which are closely related to the microenvironment of membrane-bound enzymes and influence intracellular Ca2+ metabolism. Because these changes in phospholipids and fatty acids were reversible with insulin therapy, they are diabetes-specific and might be a cause of cardiac dysfunction in diabetes.

Bilateral striate cortex contusion presenting with cerebral asthenopia rather than cortical blindness

We report a 22-year-old female with a history of contusion of bilateral occipital lobes at the age of 1 year. Magnetic resonance imaging confirmed severe lesion in bilateral striate cortices which should have resulted in cortical blindness. However, she displayed a fairly good visual function presenting only cerebral asthenopia and the restriction of the visual field. A positron emission tomography revealed that no areas other than the primary visual cortices responded to visual stimuli. Thus, her residual vision may be attributable to plasticity of the visual cortex in humans.

Efficacy of monotherapy with benazepril, an angiotensin converting enzyme inhibitor, in dogs with naturally acquired chronic mitral insufficiency

Benazepril (BP), an angiotensin convertive enzyme inhibitor, was administered orally once daily for 4 weeks to 31 dogs with mild to moderate (NYHA functional classes II and III) congestive heart failure caused from mitral insufficiency (MI). There were no significant changes in clinical signs, electrocardiogram findings, radiographical observations and plasma biochemical results in 11 dogs treated with placebo for 4 weeks. In 31 dogs treated with BP, appetite increased, and mean scores of heart failure signs, such as activity, exercise tolerance, cough and respiratory effort, were significantly improved. No dog displays signs suggesting systemic hypotension. One dog died suddenly on the 26th day of treatment with BP. This dog had good vigor and appetite till the evening before the death, and cough and exercise tolerance had been gradually improving. The heart rate and ECG parameters of BP treated dogs did not change significantly, but length of long axis of the heart decreased. In plasma biochemical tests, plasma urea nitrogen (UN) levels did not change significantly, and plasma creatinine (CRE) levels increased slightly within the normal ranges during BP trial. Two dogs had higher plasma UN levels with slightly higher plasma CRE levels, but had normal general condition and other biochemical results. Plasma ACE activity decreased to 57.3% of pre-treatment level at 4 weeks after BP treatment. It is concluded that BP monotherapy was efficacious at least in dogs with relatively low grade congestive heart failure caused by MI.

[Malignant lymphoma of the penis: report of two cases]

We report two cases of malignant lymphoma of the penis. A 64-year-old man presented with painful indurations of the penis. A computerized tomography (CT) scan showed a swollen retroperitoneal lymph node 5 cm in diameter. Penectomy confirmed the diagnosis of B cell malignant lymphoma, diffuse large type. Despite systemic chemotherapy with a CHOP regimen, he died of disease 7 months postoperatively. The second case was in a 63-year-old man presenting with multiple nodules in the penis and scrotum. Biopsy of a scrotal nodule revealed B cell malignant lymphoma, diffuse medium size type. A CT scan demonstrated widespread lesions (stage III E). He has been in complete remission for 10 months following, multidisciplinary treatments. We reviewed 21 cases of malignant lymphoma of the penis which have been reported in the literature.

New findings in the degenerating tissues of the periodontal ligament during experimental tooth movement

The degenerating tissues found in rat periodontal ligaments during tooth movement were examined morphologically, histochemically, and elementally, with decalcified and unfixed, undecalcified frozen sections. There were two types of degenerating tissues found in the compressed periodontal ligaments: One (type A tissue) was stained differently from collagen and the other (type B tissue) showed the same color as collagen. Type A tissue also showed the deposition of fibrin in Martius scalet blue and Weigert stain. The electron micrograph also showed the deposition of fibrin in type A tissue. No collagen fibers with typical bandings were seen in either tissue. The digestion experiment showed that type A tissue was digested by trypsin but not type B, whereas most of type B tissue was digested by collagenase but not type A. The backscattered electron image by scanning electron microscopy of type A tissue of the unfixed undecalcified frozen sections showed the presence of many small pieces. The elemental analysis of the pieces showed high peaks of phosphorous and calcium. These results indicate that collagen degradation, fibrin deposition, and calcification occurred in the degenerating tissues, especially in type A tissue during the experimental tooth movement.

Chemical ecology of astigmatid mites--XLV. (2R, 3R)-epoxyneral: sex pheromone of the acarid mite Caloglyphus sp. (Acarina: Acaridae)

(2R,3R)-2,3-Epoxy-3,7-dimethyl-6-octenal [(2R,3R)-epoxyneral] was identified as the female sex pheromone from an acarid mite, Caloglyphus sp. (Astigmata:Acaridae), whose phoretic hypopi had been collected from the Cockchafer, Melolontha japonica (Coleoptera: Scarabaeidae). Sexual activity of the males was induced by exposure to a 0.1-1 ng dose of synthetic (2R,3R)-epoxyneral. The enantiomer of the pheromone, (2S,3S)-epoxyneral, was inactive and its admixture did not inhibit the activity of the natural pheromone.

Surface-Sensitive XAFS in the Hard X-ray Region with Sub-Monolayer Sensitivity

Surface-sensitive X-ray absorption fine structure (XAFS) with sub-monolayer sensitivity based on grazing-incidence fluorescence detection is reported. The efficiency of fluorescence detection increased by more than two orders of magnitude by combining a multipole wiggler with a multi-element Si(Li) solid-state detector. The capability of the present technique for structural studies of surfaces and buried interfaces in the hard X-ray region was demonstrated by As K-edge XAFS studies of the InP(001) surface exposed to AsH(3) flow. The results indicated that ~0.1 monolayer As atoms are incorporated into the surface replacing the P atoms.

Preparation of unfixed and undecalcified frozen sections of adult rat periodontal ligament during experimental tooth movement

The upper first molars of adult male rats were moved for 7 days and unfixed, undecalcified frozen sections of the molar periodontal ligament were prepared and observed. The upper jaws of the rats were immersed rapidly in liquid nitrogen and sectioned with a cryostat using a super hard knife. Five micrometer serial sections were cut, collected, freeze-dried and observed with both light and scanning electron microscopy. Electron probe microanalysis (EPMA) was also performed on the sections. On the tension side of the periodontal ligament, periodontal fibers were stretched and the osteoblasts were aligned on the osteoid, which showed metamasia with the toluidine blue stain. On the pressure side where the periodontal ligament was extremely compressed, tissue degeneration was caused by tooth movement and the osteoclasts were observed on the bone surface adjacent to the degenerating tissues. Scanning electron microscopy revealed a network arrangement of the collagen fiber bundles on the tension side, but not on the pressure side of the periodontal ligament. The spectrum obtained from EPMA of the osteoid demonstrated X-ray (Ka) peaks of Na, P, S, K and Ca.

Cytochrome c oxidase activity in osteoclasts appeared in an early stage of parathyroid hormone treatment

Osteoclasts which appeared in an early stage of parathyroid hormone (PTH) administration were examined using cytochrome c oxidase activity. In the period of 1-2 hr after intraperitoneal administration of PTH, two types of osteoclasts were observed. The first type had a well-developed ruffled border characterized by deeply infolded extracellular channels, and many endocytic vacuoles were observed, as seen in control osteoclasts. Many of the mitochondria contained in the first type were with the reaction products of the enzyme on the crystal membrane and within the intermembrane space (type 1 mitochondria), and the distribution of type 1 mitochondria was similar to that seen in control osteoclasts. The second type had a ruffled border characterized by unclear extracellular channels and cytoplasmic projections. The numerical percentage of type 1 mitochondria in the second type of osteoclasts (45.3%) was significantly smaller than that in the first type (79.9%). Mitochondria which had the reaction products of the enzyme only on the crystal membrane including those with no reaction product (type 2 mitochondria) were predominant in the second type of osteoclasts. These results include two possible ways in which a morphologically regressive change of the ruffled border can occur in osteoclasts during an early stage of PTH treatment, and cytochrome c oxidase activity is closely associated with the change in the ruffled border.

Increase in vertical dimension alters mechanical properties and isometric ATPase activity in guinea pig masseter

To study the changes in mechanical and metabolic properties associated with an increase in the vertical dimension of the face, isometric tension, isometric ATPase activity, unloaded shortening velocity (Vmax), and the tension transients in response to step stretches in length were measured at constant levels of various Ca2+ activations in glycerinated masseter muscles (75 to 150 microns in diameter and about 3 mm long) from normal and bite opened (6 mm increase in the vertical dimension, period of 1 week) guinea pigs. The isometric tension increased sigmoidally with an increase in Ca2+ concentration in both preparations. However, the bite opening shifted the pCa-relative tension relationship in the direction of increasing Ca2+ required for activation, and the pCa at Km (Ca2+ concentration required to develop half maximum tension) was 6.40 +/- 0.08 in control and 6.27 +/- 0.05 in the bite opened preparations. The maximum isometric tension at the saturating Ca2+ concentration was greater in the bite opened preparation. The ATPase activity changed almost in parallel with the tension (i.e., Ca2+ concentration) in both preparations. However, the tension cost (ATPase activity/tension) was significantly (p < 0.05) lower in the bite opened preparation, compared with the control. The Vmax at the saturating Ca2+ concentration was lower in the bite opened preparations. The tension transients in response to step stretch in length were characterized by four distinct phases; the first phase of an immediate tension increase coincident with the stretch, the second phase of a rapid quasi-exponential tension reduction, the third phase of a minute tension increase and the fourth phase of a slow tension reduction.(ABSTRACT TRUNCATED AT 250 WORDS)

Water transport model during CAPD: determination of parameters

To minimize the total amount of glucose required for removing the same volume of water as a bolus, a continuous infusion of glucose during CAPD was proposed and studied. Both a computer simulation of water transport through the peritoneal membrane and in vivo assessment with rats were carried out to evaluate the feasibility of the newly proposed mathematical model in which lymphatic drainage of dialysate from the peritoneal cavity to lymphatic system was considered in addition to conventional water transport. Mass transport area coefficients (KA) of 0.041 to 0.063 ml/min/100 g body wt and 0.045 to 0.066 ml/min/100 g body wt were measured for glucose and urea during CAPD with male Wistar rats. Hydraulic conductivity of peritoneal membrane (Lc) was 7.9 x 10(-5) to 1.5 x 10(-4) ml/min/mm Hg/100 g body wt, which was calculated by a linear relationship between volume and osmotic pressure. Simulated water transport model using determined parameters indicated that the ratio of lymphatic transport to convective transport would be changeable in CAPD with glucose infusion at varying infusion rates, while up to 16% of the glucose uptake could be reduced compared with that of the common CAPD at the same dwell time.

The occurrence of mitochondrial variations including large mitochondria in osteoclasts following calcitonin treatment

Calcitonin-treated osteoclasts with mitochondrial variations, including large mitochondria, and osteoclasts not treated with calcitonin (control osteoclasts) were examined using cytochrome c oxidase activity and morphological analysis of mitochondria. The calcitonin-treated osteoclasts were divided into two types. One was osteoclasts with only a clear zone, which contained many type 1 mitochondria with the reaction products of cytochrome c oxidase in both the inner membrane of the cristae and the outer compartment in the vascular side and a comparatively small number of type 1 mitochondria in the resorptive side. The other type was osteoclasts with a mature ruffled border, in which many type 1 mitochondria were observed in both sides. Most of the large mitochondria were type 1, and these were observed only in the vascular side of the osteoclasts with only a clear zone, and in both sides of the osteoclasts with a mature ruffled border. In statistical analysis, the cross-sectional area of mitochondria in the vascular side of calcitonin-treated osteoclasts was larger than that of those in the resorptive side, and the numerical percentage of type 1 mitochondria in the vascular side was greater than that in the resorptive side. In contrast, the cross-sectional area of mitochondria in the vascular side of control osteoclasts was smaller than that in the resorptive side, and there was no significant difference between the two groups in the numerical percentage of type 1 mitochondria.(ABSTRACT TRUNCATED AT 250 WORDS)

Action of pituitary adenylate cyclase-activating polypeptide on ion transport in guinea pig distal colon

The aim of the present study was to investigate the action of pituitary adenylate cyclase-activating polypeptide (PACAP) on ion transport in the guinea pig distal colon. Submucosal/mucosal segments from distal colon were mounted in Ussing flux chambers, and increases in short-circuit current (Isc) were used as an index of secretion. Serosal addition of PACAP-38 and PACAP-27 produced concentration-dependent (10(-10)-10(-6) M) increases in Isc. Furosemide and chloride-free solutions significantly reduced the PACAP-evoked responses. Tetrodotoxin (TTX) completely blocked PACAP-evoked responses. Atropine significantly reduced the PACAP-evoked responses but did not abolish the responses. The results suggest that PACAP evokes chloride secretion through cholinergic and noncholinergic neural mechanism. Vasoactive intestinal polypeptide (VIP), peptide histidine-isoleucine amide, and helodermin evoked Isc in a concentration-dependent manner. Atropine reduced but did not abolish the VIP- and related peptides-evoked responses. TTX also significantly decreased the responses to higher concentrations of VIP and related peptides but did not abolish the responses. The results suggest that VIP and related peptides act on both submucosal neurons and the epithelial cell itself. VIP tachyphylaxis significantly decreased PACAP-38- and PACAP-27-evoked responses. These results provide evidence that PACAP recognizes, in some part, VIP receptors in the submucosal neurons to evoke chloride secretion.

The effect of orthodontic retention on the mechanical properties of the periodontal ligament in the rat maxillary first molar

The load-deformation curves obtained by extraction of the rat maxillary first molar from its socket in the dissected jaw were analyzed so that the effect of orthodontic retention on the mechanical properties of the periodontal ligament could be examined. An elastic band was inserted between the rat maxillary first and second molars for four days, and then the interdental space was filled with resin for four or eight days. The average interdental spaces between the teeth ranged from 315 to 398 microns during the experimental period. The maximum shear load, elastic stiffness, and failure energy in shear decreased markedly following application of an orthodontic force, but they increased gradually and reached control levels on the 8th day after the retention. Maximum shear deformation at maximum load was not significantly different between the experimental and control teeth during the experimental period. It is suggested that, following orthodontic tooth movement, occlusal function was restored after a relatively short retention period, as was the impaired mechanical strength of the periodontal ligament.