Relaxin induces vascular endothelial growth factor expression and angiogenesis selectively at wound sites

Relaxin is a reproductive hormone that has historically been characterized as being responsible for pubic ligament loosening and cervical ripening. Recently, relaxin has been associated with neovascularization of the endometrial lining of the uterus, potentially via specific induction of vascular endothelial growth factor. Previously conducted clinical studies using partially purified porcine relaxin have described relaxin's ability to stimulate the healing of ischemic wounds, suggesting that relaxin may also have angiogenic effects at sites of ischemic wound healing. In the present study, relaxin's angiogenic effects in the context of wound repair were tested in rodent models of angiogenesis and wound healing. Relaxin showed an ability to stimulate new blood vessel formation, particularly at ischemic wound sites, and to induce both vascular endothelial growth factor and basic fibroblast growth factor specifically in cells, presumably including macrophages, collected from wound sites. Resident macrophages collected from nonwound sites, such as the lung, did not show altered expression of these cytokines following relaxin administration. Because angiogenic wound cells are frequently macrophages, THP-1 cells, a cell line of monocyte lineage that binds relaxin specifically, were tested for and shown to induce vascular endothelial growth factor and basic fibroblast growth factor in response to relaxin. In conclusion, relaxin may be useful in the treatment of ischemic wounds by stimulating angiogenesis via the induction of vascular endothelial growth factor and basic fibroblast growth factor in wound macrophages.

A method for the isolation and serial propagation of keratinocytes, endothelial cells, and fibroblasts from a single punch biopsy of human skin

When multiple types of cells from normal and diseased human skin are required, techniques to isolate cells from small skin biopsies would facilitate experimental studies. The purpose of this investigation was to develop a method for the isolation and propagation of three major cell types (keratinocytes, microvascular endothelial cells, and fibroblasts) from a 4-mm punch biopsy of human skin. To isolate and propagate keratinocytes from a punch biopsy, the epidermis was separated from the dermis by treatment with dispase. Keratinocytes were dissociated from the epidermis by trypsin and plated on a collagen-coated tissue culture petri dish. A combination of two commercial media (Serum-Free Medium and Medium 154) provided optimal growth conditions. To isolate and propagate microvascular endothelial cells from the dermis, cells were released following dispase incubation and plated on a gelatin-coated tissue culture dish. Supplementation of a standard growth medium with a medium conditioned by mouse 3T3 cells was required for the establishment and growth of these cells. Epithelioid endothelial cells were separated from spindle-shaped endothelial cells and from dendritic cells by selective attachment to Ulex europeus agglutinin I-coated paramagnetic beads. To establish fibroblasts, dermal explants depleted of keratinocytes and endothelial cells were attached to plastic by centrifugation, and fibroblasts were obtained by explant culture and grown in Dulbecco's modified Eagle's medium (DMEM) containing fetal bovine serum (FBS). Using these isolation methods and growth conditions, two confluent T-75 flasks of keratinocytes, one confluent T-25 flask of purified endothelial cells, and one confluent T-25 flask of fibroblasts could be routinely obtained from a 4-mm punch biopsy of human skin.(ABSTRACT TRUNCATED AT 250 WORDS)

An evaluation of preemployment drug testing

As part of a blind longitudinal study, 5,465 job applicants were tested for use of illicit drugs, and the relationships between these drug-test results and absenteeism, turnover, injuries, and accidents on the job were evaluated. After an average 1.3 years of employment, employees who had tested positive for illicit drugs had an absenteeism rate 59.3% higher than employees who had tested negative (6.63% vs. 4.16% of scheduled work hours, respectively). Employees who had tested positive also had a 47% higher rate of involuntary turnover than employees who had tested negative (15.41% vs. 10.51%, respectively). No significant associations were detected between drug-test results and measures of injury and accident occurrence. The practical implications of these results, in terms of economic utility and prediction errors, are discussed.

The effect of maternal linseed supplementation and/or lamb linseed supplementation on muscle and subcutaneous adipose tissue fatty acid composition of indoor lambs

Eighty eight lambs were used in a 2×2 factorial arrangement 1) to investigate the effect of maternal dietary linseed supplementation and/or lamb linseed supplemented concentrate on growth performance, carcass fat quality and fatty acid (FA) composition of muscle and dorsal adipose tissue of indoor lambs 2) to study the relationships between subcutaneous fat quality and FA composition. Feeding linseed to ewes increased C18:3 n-3 (ALA) proportion in milk and therefore the ALA supply to suckling lambs. However, ALA and n-3 polyunsaturated FA (n-3 PUFA) proportions in lamb tissues were not affected. Feeding linseed to lambs during the post-weaning period significantly increased the proportions of ALA and n-3 PUFA in tissues. Softer and more colored fat was associated with a decrease in even medium-chain saturated FA and increases in odd and methyl FA proportions but not with ALA proportion in subcutaneous adipose tissue.

Changing patterns and prognosis of infective endocarditis in childhood

A retrospective study of 69 cases of infective endocarditis in 68 children (group I: 1971-1981; 34 children; group II: 1982-1992; 34 children) disclosed the following features: a moderate increase in the global incidence of infective endocarditis (0.5% of children hospitalized in paediatric cardiology units) and of its incidence in the very young (proportion of children less than 1 year of age: 9% in group 1 and 17% in group II); no rheumatic heart disease amongst predisposing heart diseases in children living in France; a major causal role of congenital heart diseases (72%), with an increasing incidence of previous operation (group I: 42%; group II: 56%); an increase in associated complex congenital heart diseases (group I: 11%; group II: 20%); no change in related mitral valve prolapse (5% in both groups); positive blood cultures in 76% of cases, with similar rates of Staphylococci (group I: 27%; group II: 30%) and of unusual microorganisms (15% in both groups); a major diagnostic role for echocardiography (vegetations in group II: 64%). Complications occurred in 75% of cases in both groups (pulmonary or systemic emboli, mycotic aneurysms, valvar regurgitation), leading to heart failure in 29% of group I patients and in 32% of group II patients. Mortality has decreased, from 12% in group I to 3% in group II, as a result of more frequent cardiovascular surgery (group I: 11 cases; group II: 15 cases), problems due to restrictive prostheses, and severe consequences: only 27% of group II children were cured without deterioration of their cardiac condition.(ABSTRACT TRUNCATED AT 250 WORDS)

Amyloid enhancing factor activity is associated with ubiquitin

Crude amyloid enhancing factor (AEF) drastically reduces the pre-amyloid phase on passive transfer and induces amyloid deposition in the recipient mice in 48-120 h. We attempted to purify AEF from murine amyloidotic liver and spleen extracts by using gel filtration, preparative sodium dodecyl sulphate-polyacrylamide gel electrophoresis and ion exchange chromatography and isolated a 5.5 kDa peptide. In the mouse bioassay, this peptide induced accelerated splenic AA deposition in a dose-dependent manner. Based on structural, electrophoretic and immunochemical criteria the peptide was identified as ubiquitin. A polyclonal rabbit anti-bovine ubiquitin IgG antibody (RABU) abolished the in vivo AEF activity of crude murine AEF in a dose-dependent manner. Monomeric ubiquitin and its large molecular weight adducts were isolated from crude AEF using cyanogen bromide-activated sepharose conjugated to RABU and size exclusion chromatography methods. These were assayed and were found to possess AEF activity. Furthermore, increased levels of ubiquitin, a phenomenon similar to that of AEF, were detected by immunocytochemistry in mouse peritoneal leucocytes prior to and during amyloid deposition. Since AEF shares a number of biological and functional properties with ubiquitin, we suggest a possible role of ubiquitin as an AEF, and that serum amyloid protein A and ubiquitin, the two reactants generated during inflammatory stress conditions, may converge to induce AA amyloid deposition.

Alzheimer's disease brain-derived ubiquitin has amyloid-enhancing factor activity: behavior of ubiquitin during accelerated amyloidogenesis

Amyloid-enhancing factor (AEF) is believed to be a crucial common pathogenetic link in diverse forms of human amyloidosis. Passive transfer of crude AEF is known to trigger accelerated splenic amyloid deposition in mice. We have recently identified AEF activity in ubiquitin isolated from murine amyloidotic tissues. Using similar techniques we have purified ubiquitin, from crude Alzheimer's disease (AD) brain extracts, to apparent homogeneity. Based on the partial amino acid sequence homology, immunochemical and pathophysiological criteria, the approximately 5.5-kDa AD-derived protein was identified as ubiquitin (AD-ubiquitin) with AEF activity. Ten to twenty micrograms of this protein per mouse, with or without CaCl2, in conjunction with four subcutaneous injections of 0.5 ml of 1% aqueous AgNO3, induced accelerated splenic amyloid deposition. By immunohistochemistry, using anti-mouse AA amyloid antibody, the AD-ubiquitin-induced amyloid was identified as AA type. With anti-bovine ubiquitin antibody, using similar spleen sections as above, ubiquitin was found to co-deposit with AA amyloid in the splenic perifollicular areas. These results strongly suggest that ubiquitin may be involved in the pathogenesis of amyloidosis.

The anatomical aspects of adult aortic stenosis

Since the recent introduction of percutaneous balloon valvuloplasty, there has been a renewed interest in anatomical studies. This study was based on a retrospective analysis of 100 autopsy reports and 269 surgical reports from adult patients with AS. Valvular calcification, which was always found over the age of 50 years, plays an important part in the origin of aortic stenosis (AS). Congenital or acquired aortic valvular lesions are a common pre-condition for calcified AS. Three anatomical types were found: (i) calcified bicuspid valves with anterior and posterior cusps (more frequent than a left and a right cusp) were found in 41% of autopsy reports and 40% of surgical reports. The resultant rigidity due to calcification makes the valve stenotic; (ii) post rheumatic calcified AS with strong fusion of the commissures and calcified cusps was found in 30% of autopsy reports and 8% of surgery reports; and (iii) degenerative calcific aortic stenosis was the most frequent form found over 70 years of age. The sinuses of Valsalva were filled with calcium deposits. The three commissures were apparently free, but cusp fusion was found on the ventricular aspect of the valve (29% of autopsy cases and 52% of surgical reports). Percutaneous balloon valvuloplasty is more efficient in this anatomical type.

Bacterial endocarditis presenting as acute vertebral osteomyelitis: 14 cases

Association between bacterial endocarditis (BE) and vertebral osteomyelitis (VO) has infrequently been noted. In a retrospective analysis of BE (280 cases) and VO (150 cases) 14 cases were found to have this association. There were 12 males and 2 females, ages ranging from 39 to 72 years, mean age 56.6. Blood cultures were positive for Streptococcus viridans (6 cases). Str. faecalis (4 cases), staphylococcus (2 cases), Gram negative bacteria (1 case). Organism was not isolated in one case. Fever and severe back pain antedate the diagnosis of VO 3.5 and 2.5 months. X rays films of the spine and bone scans (4 cases) revealed lumbar (6 cases) or cervical (4 cases), or dorsal (3 cases) or combined cervical and dorsal (1 case) locations. History of murmur (4 cases) and development of mitral (8 cases) or aortic (4 cases) or combined mitral and aortic (2 cases) insufficiencies were consistent with concomitant BE. Echocardiogram revealed vegetations in 6 out of 9 cases. Patients received antibiotic therapy for 3.5 months. Ten patients were cured with antibiotics only, 4 required valve replacement. One died. Thus age, sex, history of heart disease, valvular involvement, duration of symptoms prior to admission and bacteriological pictures are the same in BE with VO as in BE without VO. Survival rates are also the same if early recognition of BE and VO with prompt and prolonged antibiotic therapy may prevent severe haemodynamic or vertebral problems.

Binding of ubiquitin to experimentally induced murine AA amyloid

Amyloid enhancing factor (AEF) activity has recently been demonstrated in ubiquitin purified from amyloidotic murine tissues and Alzheimer brain extract. Since AEF is known to bind to amyloid fibrils and 'fibril-AEF' on passive transfer induces accelerated amyloidogenesis in the recipient animals, it was of interest to investigate whether ubiquitin binds to amyloid. Immunohistological studies were carried out on liver sections from amyloidotic mice. Biotin-strepavidin-peroxidase methods using monospecific rabbit anti-mouse AA amyloid IgG (RAAG) and rabbit anti-bovine ubiquitin IgG (RABU) antibodies were employed to immunostain the amyloid and ubiquitin deposits, respectively. RABU-treated liver sections were counterstained with thioflavine S. RAAG reacted strongly with the amyloid, indicating that it is AA type, and RABU-positive immunodeposits were found bound to the thioflavine-S-positive AA deposits. Treatment of the liver sections with 0.1 M sodium acetate containing 0.5 M NaCl, pH 4, for 2-3 h at 37 degrees C nearly completely desorbed the AA amyloid-bound ubiquitin. Since ubiquitin demonstrates AEF activity in vivo and binds non-covalently to AA amyloid, we suggest that ubiquitin may indeed be 'fibril-AEF' and may play a crucial role in the pathogenesis of amyloidosis. To our knowledge, this is the first time that ubiquitin bound to extracellularly deposited amyloid has been demonstrated.

Prolonged QT, atrioventricular block, and sudden death in the newborn: an electrophysiologic evaluation

An electrophysiologic study was performed in the first month of life in a patient with the congenital long QT syndrome and spontaneous episodes of 2/1 atrioventricular block. The block could be reproduced by incremental atrial pacing, and its infrahisian location was associated with a prolongation of the refractoriness in the ventricular muscle itself. Surprisingly, intravenous propranolol aggravated this phenomenon by further prolonging the QT interval. Sudden death occurred shortly thereafter during Holter monitoring and was due to a sudden resumption of normal AV conduction after an episode of 2:1 block, immediately followed by ventricular fibrillation.

Softness and fatty acid composition of subcutaneous adipose tissue, and methylmalonic acid concentrations in the plasma of intensively reared lambs

The aim of the present work was to study the relationships between lamb growth performance, soft adipose tissue and fatty acid composition of subcutaneous adipose tissue of intensively reared lambs, and to determine if the occurrence of soft fat, and of odd numbered (Odd FA) and methyl-branched-chain fatty acids in subcutaneous adipose tissue was related to plasma concentrations of methylmalonic acid (MMA). For this purpose, a sensitive gas chromatography assay to measure low plasma concentrations of MMA was developed and validated. In all, 49 male lambs were reared from 23.6 to 41.0kg. They were fed ad libitum with hay and pelleted concentrates containing either cereals (80%, C) or sugar beet pulp (70%, BP). Plasma concentrations of MMA were measured 12 days before slaughter. Softness score and fatty acid compositions of caudal adipose tissue were determined after slaughter. At the end of the trial, 75% of the carcasses had soft adipose tissue. The occurrence of soft fat appears to be related to high metabolisable energy intake per kg body weight. Soft fat was characterised by a higher water content, a lower proportion of saturated even-numbered fatty acids and higher proportions of Odd FA and methyl-branched-chain fatty acids in caudal adipose tissue, compared to firm fat. Despite high proportions of Odd FA and branched-chain fatty acids in caudal adipose tissue, plasma concentrations of MMA were low (2.02+/-1.98&mgr;mol/l). No clear relationships between MMA concentrations and soft fat or the proportions of branched-chain fatty acids other than the Iso and Anteiso acids was observed. It was concluded that the present study does not support the hypothesis that the liver's capacity to metabolise MMA was exceeded.

Latitudinal drivers of oyster mortality: deciphering host, pathogen and environmental risk factors

Diseases pose an ongoing threat to aquaculture, fisheries and conservation of marine species, and determination of risk factors of disease is crucial for management. Our objective was to decipher the effects of host, pathogen and environmental factors on disease-induced mortality of Pacific oysters (Crassostrea gigas) across a latitudinal gradient. We deployed young and adult oysters at 13 sites in France and we monitored survival, pathogens and environmental parameters. The young oysters came from either the wild collection or the hatchery while the adults were from the wild only. We then used Cox regression models to investigate the effect of latitude, site, environmental factors and origin on mortality risk and to extrapolate this mortality risk to the distribution limits of the species in Europe. We found that seawater temperature, food level, sea level atmospheric pressure, rainfall and wind speed were associated with mortality risk. Their effect on hatchery oysters was generally higher than on wild animals, probably reflecting that hatchery oysters were free of Ostreid herpesvirus 1 (OsHV-1) whereas those from the wild were asymptomatic carriers. The risk factors involved in young and adult oyster mortalities were different, reflecting distinct diseases. Mortality risk increases from 0 to 90% with decreasing latitude for young hatchery oysters, but not for young wild oysters or adults. Mortality risk was higher in wild oysters than in hatchery ones at latitude > 47.6°N while this was the opposite at lower latitude. Therefore, latitudinal gradient alters disease-induced mortality risk but interacts with the initial health status of the host and the pathogen involved. Practically, we suggest that mortality can be mitigated by using hatchery oysters in north and wild collected oysters in the south.

Ubiquitin profile and amyloid enhancing factor activity in Alzheimer and 'normal' human brain extracts

Tris-HCl or Laemmli sample buffer extracted frontal lobe and hippocampal samples from normal aged and Alzheimer's disease (AD) subjects were used to determine total ubiquitin (Ub), distribution of monomeric Ub and Ub-protein conjugates and amyloid enhancing factor (AEF) activity using the dot-blot, Western blot and mouse AEF bioassay techniques, respectively. The AD samples, as compared to the normals, demonstrated a 1.7-fold increase in total Ub, elevated levels of Ub-protein conjugates and an appreciably enhanced AEF activity. Many of the hippocampal Ub-protein conjugates were found to be soluble only in the Laemmli sample buffer. The possible roles of elevated Ub levels and of the association of AEF activity with Ub are discussed in regard to pathogenesis of brain amyloidosis.

Rearing practices identified as risk factors for ostreid herpesvirus 1 (OsHV-1) infection in Pacific oyster Crassostrea gigas spat

Early detection of Pacific oyster spat infected with ostreid herpesvirus 1 (OsHV-1) could prevent introduction of OsHV-1-infected individuals into farming areas or onshore rearing facilities, thus reducing the risk of infection of naïve oysters in such production systems. Experiments were conducted on several hundred oyster spat provided by producers in order to examine whether early rearing practices could be considered as potential risk factors for (1) OsHV-1 infection as detected by molecular methods and (2) spat mortality experimentally induced through thermal challenge. Spat groups collected on oyster beds and hatchery spat reared in growout areas during summer exhibited higher viral DNA contamination and mortalities during the trial than spat kept in onshore rearing facilities. Quantification of viral DNA before and during the trial showed that infection prevalence and intensity changed over time and revealed latent infection initially unsuspected in 3 of 10 groups. Thermal challenge induced a clear increase in the probability of detecting infected individuals, particularly for groups exhibiting significant prevalence of OsHV-1-contaminated spat prior to the challenge. The use of detection methods are discussed in relation to early rearing practices and disease control strategies.

Effect of oral exposure to the acaricide pirimicarb, a new varroacide candidate, on Apis mellifera feeding rate

BACKGROUND

The ectoparasitic honey bee mite Varroa destructor is a main cause of the gradual decline in honey bees Apis mellifera. Beekeepers currently utilize a wide range of different synthetic acaricides, organic acids and essential oils to keep mite populations under control. Previous work has indicated that pirimicarb may be a new varroacide candidate. The aim of this study was to observe chronic effects on feeding activity in worker honey bees after oral exposure to 1.05 mm pirimicarb. The long-term effects of 24 h exposure to pirimicarb were also tested.

RESULTS

After three successive trials, no mortality could be detected at the tested concentration, although oral exposure to pirimicarb had a significant effect on honey bees feeding behavior. Pirimicarb added to a sucrose solution led to a rapid decrease in food intake. These tendencies may be reversed when the pesticide is removed. However, recovery seemed to be trial dependent.

CONCLUSION

This study highlights seasonal variation in honey bee susceptibility, which should be considered in toxicology studies. © 2018 Society of Chemical Industry.

Cloning and expression in Pichia pastoris of an Irpex lacteus rhamnogalacturonan hydrolase tolerant to acetylated rhamnogalacturonan

In order to produce a recombinant rhamnogalacturonase from the basidiomycete Irpex lacteus using a molecular approach, PCR primers were designed based on a sequence alignment of four known ascomycete rhamnogalacturonases. Using 5' and 3' rapid amplification of cDNA ends (RACE) experiments, a 1,437-bp full-length cDNA containing an open reading frame of 1,329 bp was isolated. The corresponding putative protein sequence is of 443 amino acids and contains a secretion signal sequence of 22 amino acids. The theoretical mass of this protein is 44.6 kDa with a theoretical isoelectric point of 6.2. The amino acid sequence shared not only significant identities with ascomycete and basidiomycete putative rhamnogalacturonases but also complete similarity with peptides obtained from a recently purified rhamnogalacturonase from I. lacteus. The recombinant protein was successfully expressed in active form in Pichia pastoris. SDS-PAGE assay demonstrated that the recombinant enzyme was secreted in the culture medium and had a molar mass of 56 kDa. This recombinant rhamnogalacturonan hydrolase exhibited a pH optimum between 4.5 and 5 and a temperature optimum between 40°C and 50°C, which correspond to that of the native rhamnogalacturonase from I. lacteus. The study of its specificity through reaction products analysis showed that it was highly tolerant to the presence of acetyl groups on its substrate, even more than the native enzyme.

Evidence for spinodal decomposition in nuclear multifragmentation

Multifragmentation of a "fused system" was observed for central collisions between 32 MeV/nucleon 129Xe and (nat)Sn. Most of the resulting charged products were well identified due to the high performances of the INDRA 4pi array. Experimental higher-order charge correlations for fragments show a weak but nonambiguous enhancement of events with nearly equal-sized fragments. Supported by dynamical calculations in which spinodal decomposition is simulated, this observed enhancement is interpreted as a "fossil" signal of spinodal instabilities in finite nuclear systems.