Relationship between the indicators of performance and the weight of pneumonic lesions from pigs at slaughter

Lungs from pigs at slaughter were examined and the extent of the lesions was estimated as the percentage by weight of the lung affected by pneumonia in relation to the weight of the whole lung. Linear regression analyses of mean daily gain in liveweight and days to slaughter on the percentage by weight of pneumonic lung were performed. Within a range between 3.32 and 74.55 per cent for the weight of pneumonic lung, a 10 per cent increase in the weight of pneumonic lung was associated with a decrease in mean daily gain of 31.4 g and a 13.2-day increase to slaughter at 104.2 kg liveweight. When subgroups of pigs were evaluated by farm of origin, significant associations between indicators of performance and pneumonia for pigs from only one of the farms were found.

Mechanisms of myogenic enhancement by norepinephrine

Mechanisms contributing to the ability of norepinephrine (NE) to enhance arteriolar myogenic responsiveness were studied in the rat cremaster muscle. Anesthetized rats were enclosed in an airtight box that could be pressurized to increase intravascular pressure in the cremaster, which was exteriorized into a tissue bath. Vessel diameter, intravascular pressure, and red cell velocity were measured in the first-order (1A) arteriole during box pressure increases of 10, 20, and 30 mmHg. Control arterioles [diameter = 113 +/- 3 (SE) microns] did not exhibit myogenic constriction in response to step increases in intravascular pressure (e.g., + 30 mmHg, diameter = 122 +/- 5 microns), whereas after 25% constriction with NE (diameter = 85 +/- 2 microns) arterioles exhibited significant myogenic constriction (e.g., +30 mmHg, diameter = 70 +/- 4 microns). The NE effect on myogenic reactivity was augmented by Ca2+ channel agonists and inhibited by antagonists, suggesting a role for voltage-operated Ca2+ channels. In contrast to NE, exposure to KCl (30 mM) did not enhance myogenic responsiveness, suggesting that factors in addition to voltage-operated channels were involved in the NE effect. The protein kinase C (PKC) activator indolactam (1 microM) was found to increase vascular tone in the 1A arterioles (diameter = 109 +/- 6 to 89 +/- 7 microns) and to induce significant myogenic responsiveness similar to that produced by NE (e.g., +30 mmHg, diameter = 65 +/- 9 microns). Staurosporine (0.1 microM) and calphostin C (1 microM), inhibitors of PKC, significantly attenuated the NE-induced myogenic response.(ABSTRACT TRUNCATED AT 250 WORDS)

Immunohistochemical analysis of 3-B-(-) and 7-D-4 epitope expression in canine osteoarthritis

OBJECTIVE

To examine the distribution of the 3-B-3(-) and 7-D-4 epitopes in proteoglycans from morphologically normal and osteoarthritic (OA) canine articular cartilage.

METHODS

Cartilage samples from the femurs of stable and destabilized stifle joints of 9 dogs that had undergone transection of the cranial cruciate ligament were examined by immunohistochemistry.

RESULTS

The 3-B-3(-) and 7-D-4 epitopes were expressed in the superficial zone of cartilage from the destabilized femorotibial joints in the early stages of developing OA. The staining patterns with these two antibodies differed, with 3-B-3(-) reactivity confined to the superficial and upper middle zones of the articular cartilage, and 7-D-4 reactivity more prominent in the matrix, extending into the deeper zones and increasing with progression of the lesion. Both epitopes were also expressed in the superficial and upper middle zones of areas peripheral to the lesions and were detectable before the loss of matrix and proteoglycans could be identified by histochemical staining with toluidine blue.

CONCLUSION

In this study, the expression of atypical chondroitin sulfate proteoglycans was demonstrated in osteoarthritic canine cartilage, and the pattern of expression changed as the lesions progressed. The occurrence of 3-B-3(-) and 7-D-4 epitopes appears to be associated with changes in chondrocyte metabolism in the early stages of cartilage degeneration in experimental osteoarthritis.

Impaired arteriolar myogenic reactivity in early experimental diabetes

Hyperperfusion and an increase in capillary pressure has been implicated in the pathogenesis of diabetic microangiopathy. The existence of such alterations suggests that the myogenic response to increased intravascular pressure may be altered in diabetes. To examine this, in vivo studies were performed on the rat cremaster muscle microcirculation of age-matched control and STZ-induced (65 mg/kg) diabetic rats (3-4 wk of diabetes). Anesthetized rats were enclosed in an airtight Plexiglas box with the cremaster muscle exteriorized into an organ bath containing Krebs' solution. To study myogenic responsiveness, box pressure was increased in steps of 10 mmHg from 0 to 30 mmHg for 2 min. Third-order arterioles of the control animals (lumen diameter 18 +/- 2 microns) responded to increased pressure with a rapid onset vasoconstriction. In contrast, the rate of development of the constriction was markedly attenuated in similar vessels (15 +/- 1 micron) of the diabetic animals, despite their ability to exhibit a similar maximal arteriolar constriction to that of the control animals. When 20 mmHg pressure steps were applied for only 10 s, arterioles of the diabetic animals constricted minimally, whereas those of the control animals constricted to 75% of the maximal response expected for that pressure increase (P < 0.01). Second-order arterioles of both groups of animals responded with a primarily passive distension to increased intravascular pressure suggesting that the impaired responsiveness of the third-order arterioles is not compensated for by an increase in the myogenic responsiveness of upstream vessels. Basal intravascular pressures, measured in first-, second-, and third-order arterioles, were similar in control and diabetic animals.(ABSTRACT TRUNCATED AT 250 WORDS)

Beta and gamma actin mRNAs are differentially located within myoblasts

Actin is of fundamental importance to all eukaryotic cells. Of the six mammalian actins, beta (beta) and gamma (gamma) cytoplasmic are the isoforms found in all nonmuscle cells and differ by only four amino acids at the amino-terminal region. Both genes are regulated temporally and spatially, though no differences in protein function have been described. Using fluorescent double in situ hybridization we describe the simultaneous intracellular localization of both beta and gamma actin mRNA. This study shows that myoblasts differentially segregate the beta and gamma actin mRNAs. The distribution of gamma actin mRNA, only to perinuclear and nearby cytoplasm, suggests a distribution based on diffusion or restriction to nearby cytoplasm. The distribution of beta actin mRNA, perinuclear and at the cell periphery, implicates a peripheral localizing signal which is unique to the beta isoform. The peripheral beta actin mRNA corresponded to cellular morphologies, extending processes, and ruffling edges that reflect cell movement. Total actin and gamma actin protein steady-state distributions were identified by specific antibodies. gamma actin protein was found in both stress fibers and at the cell plasma membrane and does not correspond to its mRNA distribution. We suggest that localized protein synthesis rather than steady-state distribution functionally differentiates between the actin isoforms.

Effects of difloxacin on the metabolism of glycosaminoglycans and collagen in organ cultures of articular cartilage

Fluoroquinolones, including difloxacin, are potent antibacterial compounds which, as a side effect, cause lesions in articular-epiphyseal cartilage complexes (AECC) of growing animals. To evaluate the effects of difloxacin on the structure of AECC and the metabolism of sulfated glycosaminoglycans (GAG) and collagen, explants of AECC were obtained from 18 healthy, 3-month-old Beagle dogs and cultured in medium which either had no difloxacin or had the drug at one of three concentrations (40, 80, or 160 micrograms/ml). Rates of synthesis of GAG and collagen were reduced by concentrations of difloxacin that were at or above 80 micrograms/ml. The rate of synthesis of total protein, however, was reduced only at the highest dose level. Catabolism of GAG and collagen was unaffected by the treatment. The principal ultrastructural changes in affected chondrocytes were distension of rough endoplasmic reticulum with electron-dense material that was probably protein, and vacuolation of cytoplasm. Structural changes were not observed in the extracellular matrix. It, therefore, appeared plausible that difloxacin affected chondrocytes by interfering with secretion of the matrix components, GAG and collagen.

Association between growth indicators and volume of lesions in lungs from pigs at slaughter

Conflicting findings exist among studies on the effect of pneumonia on growth in pigs. We determined the extent of pneumonia in market-weight pigs by use of an objective, volumetric method and linear regression analyses of mean daily gain and days-to-slaughter weight on the percentage of pneumonic lung. In a range of extent of pneumonia between 1.33 and 70.44%, a 10% increase in the volume of pneumonic lung was associated with a decrease in mean daily gain by 41.1 g and a 16.7-day increase in number of days to a slaughter weight of 104.5 kg.

Relationship to growth performance of pneumonia and atrophic rhinitis lesions detected in pigs at slaughter among four seasons

A commercial swine herd was selected for study, because pigs at slaughter repeatedly had lung lesions consistent with enzootic pneumonia and had snout lesions typical of atrophic rhinitis. Pigs born during various seasons of the year were allotted to 4 investigations and were evaluated from birth to slaughter. Individual lungs and snouts were identified and collected at the slaughter plant and later examined for gross lesions of bronchopneumonia and atrophic rhinitis, respectively. Each lesion was scored, and the following comparisons were made within investigations: prevalence and mean scores for lung lesions; prevalence and mean grades for snout lesions; correlations between lung lesion scores and growth indicators; correlations between snout lesion grades and growth indicators; and correlations between lung lesion scores and snout grade scores. Included in the growth indicators were average daily gain during the growing phase, average daily gain during the finishing phase, average daily gain during growing and finishing phases, and days to attain 104.5 kg of body weight. Prevalence of lung or snout lesions, mean values for lung lesion scores, mean values for snout lesion grades, and mean values for the various growth indicators were tested for statistical differences among the 4 investigations. Prevalence of lung lesions was highest (96%) for winter-slaughtered and lowest (81%) for autumn-slaughtered pigs. Mean scores for lung lesions were 7% (summer), 5% (autumn), 9% (winter), and 16% (spring). Prevalence of snout lesions was highest (85%) for spring-slaughtered pigs and lowest (42%) for autumn-slaughtered pigs.(ABSTRACT TRUNCATED AT 250 WORDS)

Ultrastructural changes in articular cartilages of immature beagle dogs dosed with difloxacin, a fluoroquinolone

The ultrastructural features of quinolone-induced arthropathy were studied in the humeral and femoral heads of nine skeletally immature Beagle dogs (3 months old) that were dosed orally with difloxacin at 300 mg/kg body weight and euthanatized 24, 36, or 48 hours later in groups of three. Three age-matched dogs were given a placebo and euthanatized after 48 hours. Mitochondria in chondrocytes had significantly greater cross-sectional areas (P less than 0.05) in electron micrographs from dogs euthanatized after 48 hours of treatment than did those in other groups. There was also a significantly greater percentage of chondrocytes with swollen mitochondria in treated dogs than in the controls (P less than 0.05). These changes preceded the necrosis observed in some chondrocytes in the dogs of the 48-hour group. Disruption of extracellular matrix was first observed in the pericellular matrix of necrotic chondrocytes, indicating that this change was secondary to the changes in chondrocytes. Fissures within cartilages apparently resulted from the loss of the normal association of proteoglycans with collagen fibrils.

Morphologic and biochemical changes in articular cartilages of immature beagle dogs dosed with difloxacin

Quinolones are efficacious antibacterial compounds, but they have been associated with arthralgia in human patients; experimentally, they have caused lesions in articular cartilages of immature animals. The earliest morphologic and biochemical changes induced in articular-epiphyseal cartilage complexes by difloxacin, a fluoroquinolone, were investigated in 27 3-month-old Beagle dogs that were dosed orally with the drug at 300 mg/kg body weight per day. Paraffin-embedded sections of humeral and femoral heads that were stained with either hematoxylin and eosin or toluidine blue and fast green were evaluated histologically, and lesions were scored according to established criteria. Although morphologic changes were not observed in cartilages of the control dogs or of the treated dogs in the 24-hr group, the severity of lesions, as represented by mean scores for lesions, increased during the 36-48 hr after dosing. The initial morphologic change, observed in cartilages from the treated dogs of the 36- and the 48-hr groups, was necrosis of chondrocytes that was rapidly followed by disruption of extracellular matrix and formation of fissures. Although glycosaminoglycan was aggregated along the margins of fissures, its concentration was not reduced in cartilages of any group of treated dogs. Collagen, however, was depleted from the cartilages of the dogs that were euthanized 36 or 48 hr after the first dose of difloxacin. Because degenerative changes were observed ultrastructurally in chondrocytes by 24 hr in a previous study, it was concluded that collagen was lost from affected cartilages as an early sequel to the degeneration of chondrocytes.

Epizootic of pseudorabies among ten swine herds

An epizootic of pseudorabies in 10 swine herds located near Greensburg in Decatur County, Indiana was investigated. Records of Decatur County swine herds previously quarantined because of pseudorabies were obtained. For the 1988 epizootic, clinical findings were considered, location of each of the 10 swine herds in relation to the other herds was determined, and potential fomites were considered. Meteorologic data prior to, during, and after the epizootic were obtained, correlated, and analyzed. A source-receptor model, based on wind direction and speed data, was used to determine whether weather conditions in the Greensburg area enhanced the potential for aerosol spread of pseudorabies virus between herds. On the basis of lack of other modes of spread of pseudorabies and on meteorologic and source-receptor data, aerosol transmission of pseudorabies virus between the 10 herds was probable.

Calcium measurement in isolated arterioles during myogenic and agonist stimulation

Vascular smooth muscle calcium was measured during agonist treatment or pressure-induced stimulation of the myogenic response in isolated first-order skeletal muscle arterioles. Arterioles (40-180 microns) with spontaneous tone were isolated from rat cremaster muscle and cannulated. Arterioles were loaded with the calcium-sensitive dye fura-2 and excited at 340 and 380 nm. Images of vessel fluorescence were formed with a fluorescence microscope and digitized using an image processor coupled to a low light level camera. The fluorescent images allowed individual vascular smooth muscle cells to be seen within the arteriolar wall. Fluorescent intensity of the vessel wall, expressed as the ratio of fluorescence at 340 nm/380 nm, was used to estimate changes in vessel wall calcium. Topical application of norepinephrine (10 microM) to the arterioles caused a rapid and sustained constriction of the arterioles (64% of basal diam). The calcium response was biphasic consisting of a transient spike to 271% of basal followed by a decrease to a new steady state at 143% of basal. In comparison, steady-state indolactam (1 microM) produced a similar degree of constriction without an increase in calcium. Adenosine significantly dilated (35%) the arterioles and produced a decrease (24%) in vessel wall calcium. To investigate the myogenic response, intravascular pressure was step increased from 90 to 130 cmH2O. Increasing intravascular pressure caused an initial increase in vessel diameter of approximately 5% followed by active constriction that returned diameter to basal diameter. In association with this diameter change, estimated vessel wall calcium increased rapidly 8 +/- 2% and then continued to increase more slowly and remained elevated at 10-15% above basal levels. This study demonstrates the successful application of calcium-imaging technology in isolated arterioles for study of the role of calcium in arteriolar function. Results indicate that the calcium-contraction relationship differs for different agonists and are further consistent with a role for pressure-induced increases in vascular smooth muscle calcium during the myogenic response.

Biosynthesis of bacterial glycogen. Mutagenesis of a catalytic site residue of ADP-glucose pyrophosphorylase from Escherichia coli

Site-directed mutagenesis was used to explore the role of Lys-195 in ADP-glucose pyrophosphorylase from Escherichia coli. This residue, which is conserved in every bacterial and plant source sequenced to date, was originally identified as a potential catalytic site residue by covalent modification studies. Mutation of Lys-195 to glutamine produces an enzyme whose Km for glucose 1-phosphate is 600-fold greater than that measured for the wild-type enzyme. The effect on glucose 1-phosphate is very specific since kinetic constants measured for ATP, Mg2+, and the allosteric activator, fructose 1,6-bisphosphate, are unchanged relative to those measured for the wild-type enzyme. Furthermore, the catalytic rate constant, Kcat, for the glutamine mutant is similar to that of the wild-type enzyme. Taken together, the results suggest a role for Lys-195 in binding of glucose 1-phosphate and exclude its role as a participant in the rate-determining step(s) in the catalytic reaction mechanism. To further study the effect of charge, shape, size, and hydrophobicity of the amino acid residue at position 195, a series of mutants were prepared including arginine, histidine, isoleucine, and glutamic acid. In every case, the kinetic constants measured for ATP, Mg2+, and fructose 1,6-bisphosphate were similar to wild-type constants, reinforcing the notion that this residue is responsible for a highly localized effect at the glucose 1-phosphate-binding site and also suggesting that the protein can accommodate a wide range of substitutions at this position without losing its global folding properties. Thermal stability measurements corroborate this finding. The mutations did, however, produce a range of glucose 1-phosphate Km values from 100- to 10,000-fold greater than wild-type, which indicate that both size and charge properties of lysine are essential for proper binding of glucose 1-phosphate at the catalytic site. AMP binding was also affected by the nature of the mutation at position 195. A model for glucose 1-phosphate, ATP, and AMP binding is presented.

Cartilage canals and lesions typical of osteochondrosis in growth cartilages from the distal part of the humerus of newborn pigs

Vessels in cartilage canals supplying the articular-epiphyseal cartilage complex and growth plate of the distal part of the humerus of pigs between on day and 15 weeks old were examined in perfused and cleared specimens, and histochemical preparations. An extensive capillary network surrounded the arterioles and venules and probably maintained the circulation of blood as the ends of the cartilage canals underwent involution. Pits and grooves were in predilection sites for osteochondrosis and osteoarthrosis and were typical of early lesions of these conditions. Some ghosts that were observed mesoscopically were chondrified cartilage canals or remnants of cartilage canals in histological sections, and were considered to be the result of a normal process. However, abnormal involution may predispose to chrondrolysis, and the presence of involuting transverse cartilage canals at predilection sites implicated damaged canals in the aetiopathogenesis of osteochondrosis and osteroarthrosis in some pigs. Cleared specimens provided the most useful demonstration of the form and distribution of cartilage canals, ghosts, and pits or grooves. The association of cartilage canals with areas of chondrolysis, and the distribution of ghosts in the predilection sites for lesions, warrant further investigation of blood vessels within cartilage canals.

Personality alterations in multi-infarct dementia

Multi-infarct dementia (MID) produces changes in intellectual function and in overt behavior, but alterations in demeanor have received little systematic investigation. In this study, an assessment of personality change occurring after the onset of the dementia was performed using an inventory completed by the subjects' spouses. Personality alterations in MID were compared to those occurring in a group of healthy elderly individuals. Twelve of the 18 inventory items changed more in the MID patients than in normal control subjects. Personality changes are a consistent part of the clinical syndrome of MID and occur early in the course of the disease.

Evidence for protein kinase C involvement in arteriolar myogenic reactivity

Little information exists as to the cellular events that couple the myogenic contractile response of an arteriole to an acute rise in intravascular pressure. The aim of this study was to examine whether protein kinase C (PKC), which has been implicated in the contractile response to agonists, contributes to myogenic vasoconstriction of cremaster muscle arterioles. Studies were performed on anesthetized rats, enclosed in an airtight Plexiglas box, with the cremaster exteriorized into a bath containing Kreb's solution. Pressure in the box was increased to elevate intravascular pressure by 20 mmHg. To examine PKC involvement, studies were performed in the absence or presence of inhibitors of PKC: H 7 (10(-9)-10(-5) M) or staurosporine (10(-10)-10(-7) M). Inhibitors were added to the tissue bath and produced no observable systemic effects or alterations in arteriolar diameter. Third-order arteriole (16 +/- 1 microns diam) responses to these agents and alterations in intravascular pressure were monitored by in vivo microscopy and vessel diameter was measured with a video caliper. H 7 produced a concentration-dependent inhibition of myogenic vasoconstriction, inhibiting the extent of constriction by 75% at 10(-5) M. Similarly, staurosporine caused a concentration-dependent inhibition of pressure-induced constriction. At 10(-7) M staurosporine the myogenic response was inhibited by 82%. Further support for a role for PKC in the myogenic response was provided by the observation that indolactam (10(-6) M), a stimulator of PKC activity, induced myogenic reactivity in first-order arterioles, which under basal conditions show passive distension to increased intravascular pressure.(ABSTRACT TRUNCATED AT 250 WORDS)

Suicide from river bridges

The opening of a new high river bridge in Brisbane allowed a naturalistic experimental testing of whether the sample engaging in suicidal behaviour from the new bridge was similar to that from the adjoining older bridge. Substantial differences were found for the two samples. This suggests that persons prevented from jumping from one bridge, for example by a barrier, will not automatically jump from the alternative bridge although a minority may do so.

The development of centres of ossification of bones forming elbow joints in young swine

Epiphyseal centres of ossification in the bones forming the elbow joints of pigs between one day and 15 weeks of age were examined radiographically, macroscopically, mesoscopically and microscopically. Thoracic limbs from 39 pigs were perfused with India ink or silicone rubber injection compound and the bones were dissected free of soft tissues. The humerus, ulna and radius were fixed in formalin or ethyl alcohol and then cleared by the modified Spalteholz technique. Bones were radiographed, examined grossly, and then cut into slabs for mesoscopical evaluation. Foci considered to be calcifying within cartilaginous anlage were selected for microscopical examination. It was concluded that the epiphyseal centre of ossification develops at different times in different sites in the bones forming the elbow joint. Centres of ossification are initiated when foci of chondrocytes adjacent to one side of a cartilage canal undergo hypertrophy and the inter-territorial matrix becomes calcified. Osteogenesis then proceeds in the calcified focus, presumably with osteoprogenitor cells that originate within the cartilage canals. Subsequently, each epiphyseal centre of ossification enlarges by one of two methods. Firstly, the layer of cartilage adjacent to the centre undergoes endochondral ossification, thus allowing for the circumferential growth of the epiphyseal centre of ossification. Secondly, foci of calcification develop adjacent to the ends of cartilage canals near the epiphyseal centre of ossification and eventually the focus of calcification coalesces with the developing epiphyseal centre of ossification, thus establishing a new ossification front. Endochondral ossification continues at the periphery of the mass of bone. Mesoscopical examination is more useful than radiographical evaluation for identifying small foci of calcification which precede epiphyseal centres of ossification.

Altered cremaster muscle hemodynamics due to disruption of the deferential feed vessels

Surgical preparation of the cremaster muscle for microvascular studies typically requires disruption of collateral vessels within the muscle and between the cremaster and the structures of the epididymis/ductus deferens. To study the effect of interrupting these vascular connections on cremaster hemodynamics, two modified preparations were examined in addition to the conventional open cremaster muscle preparation. One of these preparations enabled the measurement of feed vessel (1A) pressure and diameter with all cremaster vascular connections intact. The second preparation involved interruption of intramuscle collaterals to open the cremaster sac but with intact collateral pathways between the cremaster and deferential vessels. Intravascular pressures in the main cremasteric arteriole (1A) were similar in all three preparations with pressure in the 1A, expressed as a percentage of femoral artery pressure, varying between 53% in the intact preparation and 48% in the standard open preparation. These data support the existence of substantial upstream vascular resistance regardless of the extent of surgery. Selective occlusion of the branches of the deferential vessels significantly increased red cell velocity in the cremasteric 1A and major draining venule (1V) so that calculated blood flow increased by approximately 40% (P less than 0.01) in the 1A and 95% (P less than 0.01) in the 1V. Also, intravascular pressure fell significantly (P less than 0.01) in the 1A and increased in the 1V. Despite these compensatory changes total blood flow to the muscle was reduced by approximately 40% in the standard open preparation, compared to the preparation with the deferential feed pathway intact. Further studies where the 1A flow was transiently occluded indicated that the deferential pathway was capable of providing significant collateral blood flow to the muscle. Collectively these studies demonstrate that the surgical modifications of the cremaster vascular supply required for in vivo microscopy significantly alter normal hemodynamics within the vascular bed. The surgery does not, however, entirely explain the large pressure drop that exists upstream of the cremasteric 1A.

Histologic and histochemical changes in articular cartilages of immature beagle dogs dosed with difloxacin, a fluoroquinolone

The histologic and histochemical features of quinolone-induced arthropathy were studied using 14 skeletally immature Beagle dogs (3 to 4 months old) dosed orally with difloxacin at 300 mg/kg body weight once daily for 1, 2, 5, or 7 days. A placebo was given to eight other age-matched Beagle dogs that served as controls. A scoring technique that included lesion size and histologic features was used to determine the progression of lesions. Articular-epiphyseal cartilage complexes on the femoral and humeral heads and tibial tarsal bone were identified as predilection sites. Within predilection sites on femoral and humeral heads, lesions developed in specific areas. Lesions appeared within 2 days of the onset of treatment, and lesion scores increased with time. Grossly, the lesions were raised, fluid-filled vesicles on the articular surface. Histologic changes included vesicle formation with loss of proteoglycan, clumping of unmasked collagen, and degeneration and necrosis of chondrocytes. In lesions with higher scores, chondrocytes were often in clusters or they were undergoing metaplasia toward spindle-shaped cells. Although dissolution of matrix and necrosis of chondrocytes were typical of all lesions, smaller lesions had histologically normal chondrocytes adjacent to small vesicles. In sections stained with toluidine blue, proteoglycan was aggregated with collagen fibrils or was absent from the matrix adjacent to vesicles. Unique features, such as biomechanical forces, may predispose specific areas of articular cartilage to develop lesions.

Interrater reliability of the Koppitz Developmental Scoring method in the clinical evaluation of the single case

Using the Koppitz method, Bender-Gestalt protocols of three patients (8-12 yr.), representing three commonly occurring disorders, and of one normal child were evaluated by 12 raters of varying experience with this system. Raters were asked to make provisional diagnoses based on Bender protocols alone, and these were compared with actual clinical diagnoses. Despite significant interrater reliability of Koppitz Total Developmental Scores and emotional indices, no significant agreement was found in subscores or in diagnoses made, although the effect of raters' experience was noted. Results suggest that the type of dysfunction present is a factor in raters' reliability. Results are seen, however, to support the potential of the Bender-Gestalt for use in relatively subtle diagnosis of children and highlight the differentiation of "organic" versus "developmental" factors as an area for further study.

Relationship of growth performance to pneumonia and atrophic rhinitis detected in pigs at slaughter

Three commercial swine herds were selected for study, because pigs at slaughter consistently had lung lesions typical of bronchopneumonia and snout lesions consistent with atrophic rhinitis. Pigs were reared in the conventional system for each herd except that they were identified at birth and weighted at various intervals. At slaughter, individual pig lungs and snout were examined for lesions of pneumonia and atrophic rhinitis, respectively. Lesions were scored and correlated with growth indicators for each pig. Included in the growth indicators were: average daily gain (growing phase), average daily gain (finishing phase), average daily gain (total), and days to reach 104.5-kg body weight. Additionally, for each pig, scores for lung lesions were correlated to grades for snout lesions. Three correlation coefficients for measurements of pigs within herd B were significant and included days to 104.5-kg body weight and grades for snout lesions, -0.15 (P less than 0.02); average daily gain (finishing) and grades for snout lesions, 0.17 (P less than 0.01); and average daily gain (total) and grades for snout lesions, 0.16 (P less than 0.01). Contrary to findings in other investigations, pigs that attained market weight at the youngest age did not have the lowest score for lung lesions, the lowest grade for snout lesions, or the least extensive or severe lesions. Combining data from all 3 herds, the mean scores for lung lesions and mean grades for snout lesions decreased significantly (P less than 0.05) as the age of pigs at slaughter increased. All other statistical correlations were not significant.(ABSTRACT TRUNCATED AT 250 WORDS)

Cyclooxygenase inhibition potentiates myogenic activity in skeletal muscle arterioles

The proposition that arteriolar constriction to increased intravascular pressure is mediated through either the increased local production of an eicosanoid constrictor factor or decreased production of a dilating factor was examined. The myogenic response of arterioles was studied by enclosing anesthetized rats in an airtight Plexiglas box with the cremaster muscle exteriorized into a tissue bath containing Krebs solution. Microvascular responses were observed by video microscopy. The arteriolar response to a 20-mmHg increase in intravascular pressure was examined in the absence or presence of cyclooxygenase inhibition. In the absence of cyclooxygenase inhibition, second-order arterioles (2As) responded passively to increased pressure by distending to 107 +/- 1% of control diameter. In the presence of the indomethacin, 2As constricted to 79 +/- 5% of control. Third-order arterioles (3As) constricted to 47 +/- 8% of control without indomethacin and similarly to 33 +/- 4% with indomethacin. To test whether inhibitors of endothelium-derived relaxation factor would potentiate the myogenic response of 3As, methylene blue or gossypol was topically applied to the cremaster muscle. Neither inhibitor was found to augment the myogenic vasoconstriction; however, these inhibitors were observed to significantly reduce basal vascular tone. In comparison, the tonic local production of dilating prostaglandins appears to attenuate myogenic activity as demonstrated by the appearance of myogenic activity in the normally passive 2As when exposed to cyclooxygenase inhibitors.

Organic personality disorder in dementia syndromes: an inventory approach

Personality alterations were investigated in patients with dementia of the Alzheimer type (DAT), multi-infarct dementia (MID), and normal control subjects, using a standardized informant-rated personality inventory. Personality alterations were observed in all patients, and the two diagnostic groups exhibited many similar behavioral alterations. DAT patients had significantly greater alterations in maturity and exhibited less personal control compared with the MID patients; the latter manifested more apathy and remained more affectionate and easy-going. Few correlations were found between the severity of dementia and the magnitude of behavioral changes. Personality alterations are an important and consistent aspect of the phenomenology of dementing disorders.

Suicide and related behaviour from river bridges. A clinical perspective

A survey was conducted of 47 suicides, 16 failed suicides, and 24 attempted suicides that occurred from Brisbane river bridges over 15 years. Compared with findings from other suicide surveys, subjects of bridge suicides and failed suicides had a much higher rate of schizophrenia (46%), with hallucinations often precipitating the jump. They also had extensive histories of previous self-harm. Those who attempted suicide by jumping had a higher rate of personality disorder (58%) compared with findings from other attempted suicide surveys, and had very extensive histories of previous self-harm which tended to continue beyond the bridge incident. Both groups had histories of extensive previous psychiatric care.

Regeneration of cat posterior temporalis muscle in culture

Cat posterior temporalis muscle has a rapid speed of contraction associated with a unique superfast myosin isoform. Superfast myosin expression appears to be an intrinsic property of the muscle fibres and satellite cells, though in culture they failed to express superfast myosin. We have, therefore, cultured this muscle in a system which had previously been shown to encourage the expression of an adult phenotype. The presence of nerve cells resulted in effective regeneration of cat posterior temporalis muscle and even the formation of functional neuromuscular junctions. However, superfast myosin was not found even in mature, contracting, innervated cultures. Thyroid hormone, a known regulator of myosin isoform expression, also failed to elicit superfast myosin expression. Different culture conditions may allow a different outcome, but under circumstances in which mouse muscle expresses an adult phenotype, cat posterior temporalis muscle fails to do so.

Altered microvascular reactivity in streptozotocin-induced diabetes in rats

This study examined the effect of short-term streptozotocin-induced diabetes in rats on the response of cremaster muscle arterioles to angiotensin II (ANG II) and vasodilatory prostaglandins. Topically applied ANG II (10(-10) to 10(-6) M) caused significantly greater vasoconstriction of third-order arterioles in diabetic animals in comparison with controls. For example, in response to 10(-6) M ANG II arterioles of the diabetic animals constricted to 43 +/- 10% of basal diameter compared with controls' 67 +/- 6% (P less than 0.05). Furthermore, the magnitude of the secondary vasodilatation after ANG II-induced constriction was decreased in diabetic animals (108 +/- 4 and 131 +/- 9%, P less than 0.025). Cyclooxygenase inhibition resulted in marked arteriolar constriction, with this effect being less evident in diabetic animals. In response to indomethacin (2.8 x 10(-5) M), arterioles of the diabetic animals constricted to 84 +/- 7% of basal diameter compared with 56 +/- 4% in controls (P less than 0.01). Arterioles of the diabetic animals were less responsive to exogenous prostaglandin I2 (PGI2) and PGE2 (10(-12) to 10(-6) M) despite evidence of increased in vitro PGI2 production. The data demonstrate potentiation of the vasoconstrictor response and a diminution of the secondary vasodilator response to ANG II in experimental diabetes. These alterations may be due, in part, to decreased responsiveness of skeletal muscle arterioles to vasodilatory prostaglandins.

Personality alterations in dementia of the Alzheimer type: a three-year follow-up study

Alterations in personality accompany the onset and progression of dementia of the Alzheimer type. Longitudinal investigations of these changes using systematic quantifiable documentation have been infrequent. In this 3-year follow-up study, we report longitudinal observations of changes in personality in dementia of the Alzheimer type. Four response patterns were observed: (1) change at onset with little change as the disease continued, (2) ongoing change as the disorder progressed, (3) no change, and (4) regression of previously more disturbed behaviors. Repeated characterizations of the premorbid personality profile as determined by this inventory were found to be reliable.

Alterations in distribution of cardiac output in experimental diabetes in rats

Alterations in blood flow distribution in streptozotocin-induced diabetes in the rat were examined. Blood flow between tissues was estimated by the distribution of radiolabeled microspheres, and a second series of experiments examined skeletal muscle microcirculation by in vivo microscopy. Studies were performed in anesthetized rats 1-8 wk after induction of diabetes. Cardiac index was transiently increased in diabetic animals (29.6 +/- 1.0 ml.min-1.100 g-1) in comparison with control animals (23.0 +/- 1.4 ml.min-1.100 g-1) at 2-wk duration. Cardiac index was similar in both groups of animals at all other time points studied. The increased cardiac index coincided with transiently increased blood flow to diaphragm and abdominal wall and a significant vasodilatation of small cremaster muscle arterioles. Blood flow to skin and some skeletal muscles was thereafter significantly decreased in the diabetic animals. Blood flow (ml.min-1.100 g-1) to the brain and main thoracic and abdominal organs was similar in nonfasting control and diabetic animals throughout the period of study. As a result of hyperplasia, blood flow to the small intestine (%cardiac output) was increased in the diabetic animals (at 4 wk of diabetes, 34.5 +/- 2.1 vs. 17.5 +/- 0.8%, P less than 0.001). Despite reduction in blood flow to the intestine, by dietary restriction, flow to skin and skeletal muscle remained significantly decreased. Insulin treatment, at a dose aimed at preventing body weight loss but maintaining hyperglycemia, led to renal hyperperfusion in comparison with untreated diabetic and control animals. The alterations in regional blood flow appear progressive in nature and are not simply related to each other but may reflect tissue adaptation to the metabolic disorder.

Localization of dystrophin in cultures of human muscle

Dystrophin is a protein present in normal human muscle but absent in patients with Duchenne muscular dystrophy (DMD). Using a specific antibody, we have investigated the expression of dystrophin in human muscle which had regenerated in culture in the presence of nerve cells. Dystrophin was present and was correctly localized in the cultures of normal muscle but was absent from cultures of muscle from patients with DMD. Its control and function can now be studied.

Biosynthesis of bacterial glycogen. Determination of the amino acid changes that alter the regulatory properties of a mutant Escherichia coli ADP-glucose synthetase

The ADP-glucose synthetase of Escherichia coli K12 mutant 618 has a higher apparent affinity for the activator, fructose 1,6-P2 and a lower apparent affinity for the inhibitor, 5'-AMP, than the normal enzyme. The structural gene, glgC, of the mutant enzyme has been cloned and sequenced (Lee, Y. M., Kumar, A., and Preiss, J. (1987) Nucleic Acids Res. 15, 10603). Substitutions in the mutant enzyme were amino acid residues 296 (Lys to Glu) and 336 (Gly to Asp). Single mutant enzymes, Glu296 and Asp336, were constructed using oligonucleotide-directed mutagenesis. The Glu296 enzyme had the same allosteric kinetic constants as the wild type enzyme. The Asp336 enzyme was catalytically defective. Thus, the mutations at 296 and at 336 separately could not account for the allosteric alterations of the mutant enzyme. A hybrid glgC gene was prepared from genes of wild type and mutant 618 glgC using DNA recombinant techniques. The C-terminal portion of mutant 618 containing Glu296 and Asp336, combined with the N-terminal portion of wild type enzyme, showed allosteric and substrate kinetics similar to mutant 618 enzyme. Thus, alteration of the normal allosteric properties in mutant 618 are due to changes of both Lys296 to Glu and Gly336 to Asp.

Tardive dyskinesia in schizophrenic patients: correlation with negative symptoms

The relationship between severity of tardive dyskinesia (TD) and the prominence of negative symptoms was assessed in 25 right-handed, medicated schizophrenic patients. TD was quantified using ultrasound detectors and frequency measurement techniques as well as with observer rating scales. Electromechanical studies revealed a systematic relationship between TD severity and negative symptoms; TD was more severe in patients with fewer negative symptoms. The correlation was small in magnitude.

The vascular supply of the chondro-epiphyses of the elbow joint in young swine

The vasculature of the elbow joint was examined in 39 pigs between one day and 15 weeks of age. Each pig was anaesthetised, exsanguinated and the thoracic limbs were perfused with India ink or a silicone rubber injection compound. The humerus, ulna and radius were dissected free, examined, fixed in formalin or ethyl alcohol, cleared by the modified Spalteholz technique and examined mesoscopically. Features of interest were photographed and then a limb from two pigs in each age group was cut into slabs and examined mesoscopically. The vascular supply of the distal part of the humerus was complex. It was supplied by vessels on both the cranial and caudal aspects and locally each aspect had a dual blood supply. Vessels anastomosed and on the cranial aspect formed a vascular ring. The proximal part of the ulna was supplied by vessels that were on its medial and lateral surfaces. The vessel on the lateral surface continued distally and supplied the lateral aspect of the proximal part of the radius. The proximal part of the radius was also supplied by arteries that were on the cranial and medial surfaces. Blood vessels provided branches to numerous cartilage canals of the articular-epiphyseal cartilage complexes, epiphyseal centres of ossification, and growth plates. The patterns of blood vessels in cartilage canals which were in sagittal or transverse planes were best exemplified by those in the distal part of the humerus. Perforating cartilage canals emerged from the epiphyseal centres of ossification. The pattern of cartilage canals was consistent in a general configuration, but individual variation did occur. Although cartilage canals were abundant in the youngest pigs, with increasing age the distribution of cartilage canals changed and the numbers of cartilage canals decreased.

Estimation of parameters and missing values under a regression model with non-normally distributed and non-randomly incomplete data

We carried out a simulation study to compare the performance of three algorithms (complete cases, ALLVALUE, and expectation maximization, EM) in estimating regression parameters and missing values for situations that have varying amounts of missing data, distributions (normal, mixture of normals and lognormal), patterns of incomplete data (random, related and censored), and degrees of correlational structure among the dependent and independent variables. We found that the EM and complete cases algorithms performed equally well regardless of the correlational structure, when the percentage of incomplete data was only 5 per cent. When this percentage increased to 25 per cent, the EM algorithm was generally best for estimation, but the complete cases algorithm was safe and conservative. This finding may be attributed to the study design, which required that the slopes be the same in the population of all cases, and in the population of complete cases. In addition, the one-step imputing method (ALLVALUE) was competitive only for situations with weak correlational structure and/or little missing data. In that situation the bias caused with use of all available information was less than that caused with use of only complete cases. On the other hand, for imputation, the EM algorithm performed optimally, even in situations of censored or log-normally distributed data.

Comparison of electromechanical measures and observer ratings of tardive dyskinesia

Thirty-three patients with tardive dyskinesia (TD) were studied with multiple-observer consensus ratings of videotaped examinations, ultrasound counts of movement, and electromechanical frequency measures of the movements. There were statistically significant correlations between orofacial ultrasound measures and TD severity determinations made by observers. Clinical ratings did not correlate with frequency measures. Ultrasound measures substantiate observer rating scales, whereas frequency measures appear to provide information not available from clinical rating scale scores.

Personality alterations in dementia of the Alzheimer type

Personality alterations in dementia of the Alzheimer type (DAT) are common but have received little systematic or quantitative investigation. In this study, changes in personality in patients with DAT were compared with those of nondemented retirees using a personality inventory. The inventory used information obtained from each subject's spouse. No personality changes were identified in the control subjects when pre- and post-retirement inventory scores were compared, whereas patients with DAT had highly significant alterations on 12 of the 18 inventory items. The results demonstrate that patients with DAT become more passive, more coarse, and less spontaneous as a result of the disease. Personality changes are a consistent part of the clinical syndrome of DAT and occur early in the course of the disease.

Vascular dementia and dementia of the Alzheimer type. Cognition, ventricular size, and leuko-araiosis

Multi-infarct dementia (MID) and dementia of the Alzheimer type (DAT) were compared with regard to ventricular size and leuko-araiosis (LA) on computed tomographic scans. Ninety-seven percent of patients with MID and 55.5% of patients with DAT had evidence of LA. The severity of LA was scored with a 0 through 4 rating system, and LA was found to be significantly more severe in patients with MID than in patients with DAT. Patients with MID, but not those with DAT, exhibited correlations between enlargement of the third and lateral ventricles and severity of cognitive impairment.

The influence of insulin and sorbinil on myoinositol uptake in peripheral nerve from normal and diabetic rats and a neuroblastoma cell line (N1E-115)

The uptake of myo-inositol was investigated in femoral nerve fascicular preparations taken from control and streptozotocin-diabetic rats and in a clonal murine neuro-blastoma cell line (N1E-115), as a model of the neuronal component of the nerve preparation. Uptake was investigated in medium containing glucose, 5.6-25 mmol/l and inositol, 4 x 10(-5) mol/l. In the presence of glucose (25 mmol/l) myo-inositol uptake was decreased in nerve taken from streptozotocin-diabetic animals when compared to control (26.4 +/- 2.2 pmol/100 micrograms protein/2 h vs 55.1 +/- 2.4 pmol/100 micrograms protein/2 h, p less than 0.005). Uptake in both preparations was higher in the presence of insulin added during the uptake experiment (73.4 +/- 5.7 pmol/100 micrograms protein/2 h and 64.4 +/- 3.9 pmol/100 micrograms/2 h, respectively). Prior treatment of the animals with insulin or with the aldose reductase inhibitor, sorbinil also resulted in an increase in myo-inositol uptake in streptozotocin diabetic nerve preparations. In control nerve preparations and in N1E-115 cells raising the glucose concentration from 5.6 through 25 mmol/l was associated with decreased myo-inositol uptake, with an inhibitory constant (Ki) of 21.4 mmol/l and 20.4 mmol/l for femoral nerve and N1E-115 cells respectively. An increase in myo-inositol uptake was found in N1E-115 cells, following pre-treatment of cells in culture with sorbinil or inclusion of insulin during the uptake experiment. Altered myoinositol metabolism may play a role in the functional and structural changes characterizing diabetic neuropathy. The effects of hyperglycaemia on myo-inositol uptake in experimental diabetes may be modified by insulin or by inhibition of sorbitol accumulation.(ABSTRACT TRUNCATED AT 250 WORDS)

Alzheimer's disease and Parkinson's disease: comparison of speech and language alterations

Speech and language alterations were assessed in 51 patients with Parkinson's disease (PD) and 10 patients with dementia of the Alzheimer type (DAT). Thirty-five of the PD patients had no evidence of intellectual impairment on a conventional mental status questionnaire and 16 of the PD patients had dementia syndromes of comparable severity to the DAT patients. DAT produced significantly greater language disturbances, including anomia, decreased information content of spontaneous speech, and diminished word list generation. PD patients had significantly decreased phrase length, impaired speech melody, dysarthria, and agraphia. The results suggest that the dementia of PD is distinguishable from that of DAT:PD patients have prominent motor speech abnormalities, whereas DAT patients exhibit more profound language alterations.

Speech and language alterations in multi-infarct dementia

Speech and language functions were assessed in 18 patients with multi-infarct dementia (MID) and 14 with dementia of the Alzheimer type (DAT). The age range and dementia severity of the two groups were comparable. We used a speech and language battery assessing 37 elements of verbal output to characterize alterations in the patients. MID patients had more abnormalities of motor aspects of speech, whereas DAT patients had empty speech, more marked anomia, and relative sparing of motor speech functions. The results demonstrate that speech and language differ in MID and DAT. In addition, MID patients exhibited common clinical features despite the heterogeneity of the syndrome.

Reaction of rat liver phenylalanine hydroxylase with fatty acid hydroperoxides. Characterization and mechanism

Rat liver phenylalanine hydroxylase must be in a reduced form to be catalytically active (Marota, J.J. A., and Shiman, R. (1984) Biochemistry 23, 1303-1311). In this communication we show that a fatty acid hydroperoxide, 13-hydroperoxylinoleic acid (LOOH), can efficiently oxidize the reduced enzyme. In the process, the hydroperoxide is decomposed, oxygen consumed, and hydrogen peroxide formed. Enzyme reduction by the tetrahydropterin cofactor and reoxidation by LOOH can occur as two single steps or, when the enzyme concentration is low compared to that of the substrates, as part of a catalytic cycle. In this latter case, phenylalanine hydroxylase is a hydroperoxide-dependent tetrahydropterin oxidase. The reaction requires 1.0 mol of O2, 1.0 mol of tetrahydropterin, and 0.5 mol of LOOH to yield 1.0 mol of quinonoid dihydropterin, 0.4 mol of H2O2, and fatty acid products. Thus far, the catalytic and single-step reactions appear the same in all properties, consistent with the steady-state reaction following a ping-pong mechanism. Phenylalanine hydroxylase is an excellent catalyst for this reaction: the turnover number with LOOH is slightly greater than with phenylalanine; the Km(app) for LOOH is 11 +/- 4 microM; and the kcat/Km ratio for LOOH is about 25 times greater than for phenylalanine. LOOH and phenylalanine appear to react at different sites on phenylalanine appear to react at different sites on phenylalanine hydroxylase, and the reaction of LOOH is inhibited only slightly by phenylalanine and not at all by 5-deaza-6-methyltetrahydropterin, a competitive inhibitor of phenylalanine hydroxylation. The reaction of LOOH with phenylalanine hydroxylase strongly resembles the nonenzymatic reaction of LOOH with hematin, implying similar mechanisms for the two reactions and implicating the enzyme's non-heme iron as both the site of reaction of LOOH and of electron transfer during oxidation and reduction. The formation of hydrogen peroxide during a reaction of phenylalanine hydroxylase is unusual. Indirect evidence indicates a reduced oxygen species, formed on the enzyme during the reduction step, is (partially) released as H2O2 when the hydroperoxide reacts.

Histochemical morphologic features of growth cartilages in long bones of pigs of various ages

Growth cartilages were obtained from humeri, femora, and ulnae of 31 pigs between 1 and 169 days old. On the basis of stain uptake and distribution, distinct layers were identified in articular-epiphyseal cartilage complexes and growth plates. The laminated appearance was dependent on stain uptake by territorial and interterritorial matrices and was more distinct in pigs greater than 15 days old. There was morphologic heterogeneity, which probably represented a functional heterogeneity, among chondrocytes in all layers and zones of both types of growth cartilage. The laminar appearance of growth cartilages and the distribution of different types of cells were similar for all pigs in each age category and for all sites.

Age at marriage in Malaysia: a hazard model of marriage timing

"This paper estimates a proportional hazards model for the timing of age at marriage of women in Malaysia. We hypothesize that age at marriage responds significantly to differences in male and female occupations, race, and age. We find considerable empirical support for the relevance of economic variables in determining age at marriage as well as evidence of strong differences in marriage patterns across races."

The growth of motoneurones and their neurites in relation to Schwann cells harvested from sciatic nerve

A study has been made of the effects of Schwann cells isolated from neonatal sciatic nerve on motoneurones in culture. Motoneurones were identified in dissociated spinal cord cultures from 6-day avian embryos by prior retrograde labelling with rhodamine-latex microspheres. Schwann cells trebled the expression of long neurites in these motoneurones over that in control media as well as maintaining them viable for 24 h. A transformed Schwann cell line, RN22, produced similar results. These effects were mediated by a soluble factor(s) released from the Schwann cells which was distinct from nerve growth factor. Schwann cells exerted this initiation of neurites on homogeneous cultures of motoneurones, indicating that other spinal cord cells are not necessary to mediate this effect. The observations are discussed in terms of the hypothesis that Schwann cells guide motor axons during regeneration and formation of limb and muscle nerves.