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PubMedDate not supplied

[Return of immigrants: a cluster analysis of mesotheliomas among residents of the Veneto region who used to work at the ETERNIT AG factory at Niederurnen, Switzerland].

We identified 5 mesotheliomas among Italian migrant workers who returned home and settled in the Veneto Region, after employment at the ETERNIT AG factory in Switzerland. During the 1970s the factory employed about 1000 workers and the presence of Italian migrants was relevant. The cluster confirms that migration for work has caused exposures to carcinogenic substances and confirms that neoplastic diseases are occurring among those resettled in Italy and helps explaining the high occurrence of mesotheliomas in this country.

Catchment Area, Health↗
PubMed1996

Inhibition of angiogenesis in human glioblastomas by chromosome 10 induction of thrombospondin-1.

Glioblastoma multiforme is distinguished from its less malignant astrocytoma precursors by intense angiogenesis and frequent loss of tumor suppressor genes on chromosome 10. Here we link these traits by showing that when a wild-type chromosome 10 was returned to any of three human glioblastoma cell lines U251, U87, or LG11, they lost their ability to form tumors in nude mice and switched to an antiangiogenic phenotype, as measured by the inhibition of capillary endothelial cell migration and of corneal neovascularization. This change in angiogenesis was directly due to the increased secretion of a potent inhibitor of angiogenesis, thrombospondin-1, because: (a) neutralizing thrombospondin completely relieved the inhibition; (b) the inhibitory activity of thrombospondin was not dependent on transforming growth factor beta; and (c) chromosome 10 introduction did not alter secreted inducing activity. The inducing activity was dependent on vascular endothelial cell growth factor and had an ED50 of 10 microg/ml in media conditioned by parental cells and 9-13 microg/ml in media conditioned by chromosome 10 revertants. Normal human astrocytes were also antiangiogenic due to secreted thrombospondin. The effect of chromosome 10 on thrombospondin production in vitro was reflected in patient material. Normal brain and lower grade astrocytomas known to retain chromosome 10 stained strongly for thrombospondin, but 12 of 13 glioblastomas, the majority of which lose chromosome 10, did not. These data indicate that the loss of tumor suppressors on chromosome 10 contributes to the aggressive malignancy of glioblastomas in part by releasing constraints on angiogenesis that are maintained by thrombospondin in lower grade tumors.

Animals↗
PubMed1997

Oncostatin M induces basic fibroblast growth factor expression in endothelial cells and promotes endothelial cell proliferation, migration and spindle morphology.

Oncostatin M (OSM), a pleiotropic cytokine originally isolated from supernatants of the U937 histiocytic lymphoma cell line, has been shown to have regulatory effects on a wide variety of cultured and tumor cells. We investigated the effects of OSM on basic fibroblast growth factor (bFGF) gene expression in bovine arterial endothelial (BAE) cells. Levels of bFGF mRNA transcripts were low in uninduced BAE cells, were maximal at 8 hours of exposure to OSM, and returned to control levels by 24 hours. Induction of bFGF mRNA transcripts by OSM was dose-dependent. Nuclear transcriptional run-on analysis demonstrated that exposure of BAE cells to OSM stimulated bFGF gene transcription. OSM treatment of BAE cells enhanced the synthesis of bFGF protein as determined by ELISA assays. Immunocytochemistry studies demonstrated the presence of low levels of bFGF protein within the cytoplasm in uninduced cells. After stimulation for 8 hours with OSM there was significant staining for bFGF in the cytoplasm. However, 24 hours after exposure to OSM, bFGF antigen was located only within the nuclei. Western blot analysis demonstrated that OSM stimulated predominantly the synthesis of a 22 kDa form of bFGF. In addition, OSM stimulated endothelial cell proliferation and migration as well as acquisition of a spindle shape. Phosphorothioate antisense oligonucleotide directed against bFGF inhibited OSM induced BAE cell proliferation and spindle shape formation but had only a minimal effect on migration. The levels of the 22 kDa form of bFGF were reduced by antisense treatment indicating that OSM induced proliferation and morphology change is likely to be regulated by intracellular bFGF. Our studies suggest that OSM released at sites of vascular injury could stimulate angiogenesis by inducing bFGF synthesis, endothelial cell proliferation and migration.

Animals↗
PubMed1997

Inflammatory and anti-inflammatory effects of soybean agglutinin.

Soybean agglutinin (SBA) lectin, a protein present in raw soybean meals, can bind to and be extensively endocytosed by intestinal epithelial cells, being nutritionally toxic for most animals. In the present study we show that SBA (5-200 micrograms/cavity) injected into different cavities of rats induced a typical inflammatory response characterized by dose-dependent exudation and neutrophil migration 4 h after injection. This effect was blocked by pretreatment with glucocorticoid (0.5 mg/kg) or by co-injection of N-acetyl-galactosamine (100 x [M] lectin), but not of other sugars (100 x [M] lectin), suggesting an inflammatory response related to the lectin activity. Neutrophil accumulation was not dependent on a direct effect of SBA on the macrophage population since the effect was not altered when the number of peritoneal cells was increased or decreased in vivo. On the other hand, SBA showed chemotactic activity for human neutrophils in vitro. A slight increase in mononuclear cells was observed 48 h after i.p. injection of SBA. Phenotypic analysis of these cells showed an increase in the CD4+/CD8- lymphocyte population that returned to control levels after 15 days, suggesting the development of an immune response. SBA-stimulated macrophages presented an increase in the expression of CD11/CD18 surface molecules and showed some characteristics of activated cells. After intravenous administration, SBA increased the number of circulating neutrophils and inhibited in a dose-dependent manner the neutrophil migration induced by i.p. injection of carrageenan into peritoneal cavities. The co-injection of N-acetyl-galactosamine or mannose, but not glucose or fucose, inhibited these effects. The data indicate that soybean lectin is able to induce a local inflammatory reaction but has an anti-inflammatory effect when present in circulating blood.

Animals↗
PubMed1995

Vagal control of fasting somatostatin levels.

UNLABELLED: The relationship between fasting intestinal motility, plasma concentration of somatostatin and vagal integrity was examined in four conscious dogs. Small intestinal motility was recorded using subserosally implanted bipolar electrodes. The cervical vagosympathetic trunks, previously isolated in skin loops, were blocked by cooling. In the fasted state, peaks in somatostatin concentration were observed during phase III of the migrating myoelectric complex (MMC). During vagal blockade, small intestinal MMCs persisted but with phase II being absent or decreased in duration in the duodenum and upper jejunum. Somatostatin levels significantly decreased to below the basal levels observed prior to blockade. No cycling of somatostatin levels was evident during the period of vagal blockade. Upon termination of vagal cooling, normal motility returned and somatostatin levels returned to their pre-blockade levels. IN CONCLUSION: (1) plasma somatostatin levels cycle with phase III of the MMC in the upper small intestine; (2) the cycling of fasting somatostatin concentrations is primarily dependent upon intact vagal pathways; and (3) basal plasma somatostatin levels are in part vagally dependent.

Adaptation, Physiological↗
PubMed2006

Saccades, salience and attention: the role of the lateral intraparietal area in visual behavior.

Neural activity in the lateral intraparietal area (LIP) has been associated with attention to a location in visual space, and with the intention to make saccadic eye movement. In this study we show that neurons in LIP respond to recently flashed task-irrelevant stimuli and saccade targets brought into the receptive field by a saccade, although they respond much to the same stimuli when they are stable in the environment. LIP neurons respond to the appearance of a flashed distractor even when a monkey is planning a memory-guided delayed saccade elsewhere. We then show that a monkey's attention, as defined by an increase in contrast sensitivity, is pinned to the goal of a memory-guided saccade throughout the delay period, unless a distractor appears, in which case attention transiently moves to the site of the distractor and then returns to the goal of the saccade. LIP neurons respond to both the saccade goal and the distractor, and this activity correlates with the monkey's locus of attention. In particular, the activity of LIP neurons predicts when attention migrates from the distractor back to the saccade goal. We suggest that the activity in LIP provides a salience map that is interpreted by the oculomotor system as a saccade goal when a saccade is appropriate, and simultaneously is used by the visual system to determine the locus of attention.

Animals↗
PubMed1995

Strong natural selection causes microscale allozyme variation in a marine snail.

Natural selection is one of the most fundamental processes in biology. However, there is still a controversy over the importance of selection in microevolution of molecular traits. Despite the general lack of data most authors hold the view that selection on molecular characters may be important, but at lower rates than selection on most phenotypic traits. Here we present evidence that natural selection may contribute substantially to molecular variation on a scale of meters only. In populations of the marine snail Littorina saxatilis living on exposed rocky shores, steep microclines in allele frequencies between splash and surf zone groups are present in the enzyme aspartate aminotransferase (allozyme locus Aat; EC. 2.6.1.1). We followed one population over 7 years, including a period of strong natural perturbation. The surf zone part of the population dominated by the allele Aat100 was suddenly eliminated by a bloom of a toxin-producing microflagellate. Downshore migration of splash zone snails with predominantly Aat120 alleles resulted in a drastic increase in surf zone frequency of Aat120, from 0.4 to 0.8 over 2 years. Over the next four to six generations, however, the frequency of Aat120 returned to the original value. We estimated the coefficient of selection of Aat120 in the surf zone to be about 0.4. Earlier studies show similar or even sharper Aat clines in other countries. Thus, we conclude that microclinal selection is an important evolutionary force in this system.

Animals↗
PubMed2004

Olecranon osteotomy for exposure of fractures and nonunions of the distal humerus.

Although olecranon osteotomy provides excellent exposure of the distal humerus, enthusiasm for this approach has been limited by reports suggesting numerous complications. It has been suggested that specific techniques for creating and repairing an olecranon osteotomy may help limit complications. This paper describes a technique for olecranon osteotomy using an apex, distal, chevron-shaped osteotomy, Kirschner wires directed out the anterior ulnar cortex distal to the coronoid process and bent 180degrees and impacted into the olecranon proximally, and two 22- gauge, figure-of-eight, stainless steel tension wires. A single surgeon used this technique for exposure of a fracture (16 patients) or nonunion (29 patients) of the distal humerus in 45 consecutive patients. One patient returned to activity too soon, had loosening of the wire fixation, and required a second operation for plate fixation of the ulna. The remaining 44 osteotomies (98%) healed with good alignment within 6 months. There were no broken or migrated wires prior to healing. Twelve patients (27%) had removal of the wires used to repair the olecranon: in 6 patients, this was for symptoms related to the wires (13%); 1 for septic olecranon bursitis, and 5 at the time of another procedure (elbow capsular release in 4 patients and submuscular ulnar nerve transposition in 1). Olecranon osteotomy can be used for exposure of the distal humerus with a low rate of complications when specific techniques are used.

Adolescent↗
PubMed1993

Chemosensory orientation behavior in juvenile sea turtles.

It has been widely believed for several decades that hatchling sea turtles imprint to chemical cues characteristic of their natal beach and use this information as part of a repertoire of mechanisms enabling their return to the same beach for mating and nesting. This has proven very difficult to test. Although the imprinting theory is conceptually simple, functionally it is quite complex. This involves not only chemical imprinting of nestlings but growth and migration to habitats where the adults are found, long-term memory of their earlier chemical exposure, reproductive maturation, and homing. A few studies have been conducted to examine these elements of the imprinting theory. Experiments involving the exposure of embryos and hatchlings to chemicals suggest that juvenile turtles 'imprint' to the chemical environment of their nest. This can be termed chemical imprinting. Loggerhead turtles, Caretta caretta, and ridley turtles, Lepidochelys kempi, appear to be attracted to chemicals (morpholine and natural seawater, respectively) to which they were exposed as embryos. The strongest support for chemical imprinting is that six-month-old green turtles, Chelonia mydas, exposed to either morpholine or 2-phenylethanol in the nest and for a period of time after hatching, respond similarly to the chemical to which they were exposed as nestlings. Although chemical imprinting does not 'prove' the imprinting theory of turtle homing, it is a necessary component of the theory not previously examined.

Animals↗
PubMed2002

Economic and demographic factors affecting mangrove loss in the coastal provinces of Thailand, 1979-1996.

The following paper analyzes the economic and demographic factors determining the conversion of mangroves in the coastal provinces of Thailand to commercial shrimp farming. Mangrove conversion therefore is determined by the returns to shrimp farmers, (i.e. the price of shrimp), the input costs to farming shrimp (e.g. feed price and wages) and the "accessibility" of mangrove areas. Additional exogenous influences, such as income per capita, population growth, and in-migration (i.e. the number of shrimp farms) also are important. Both a mangrove conversion and a shrimp farm expansion relationship are estimated empirically through a panel analysis across 21 coastal provinces of Thailand between 1979-1996. Results show that the price of shrimp, minimum wage, distance from market, feed price, population growth, income per capita, and shrimp-farm density all have important influences on mangrove loss due to shrimp farming in Thailand.

Animals↗
PubMed1975

Internodal conduction. Immediate and long-term effects of transverse circular incision of right atrium including atrial septum.

Immediate and long-term effects of a transverse circular incision of the entire right atrium, including the atrial septum, on internodal conduction were studied in 7 dogs. Electrocardiograms were followed up to 35 weeks, and the atrial epicardial excitation sequence was evaluated in all 7 dogs. The findings were compared with data from 3 normal dogs and 3 other dogs which underwent total atrial transverse incisions. All dogs with total atrial separation developed complete atrioventricular (A-V) block immediately after the operation and died within 3 days. All dogs with right atrial interruption exhibited persistent sinus rhythm with slight extension of P-R intervals and a normal QRS immediately after the operation. The mean P-R interval reached its maximum at the fourth day (50 per cent increase), remained prolonged through the first week, but returned to near control valves after 12 weeks. Three days later developed transient arrhythmia; sinus arrhythmia; sinus arrhythmia in 2 dogs and second-degree block in 1 appeared between the tenth and fourteenth postoperative days. Postoperative P vectors migrated toward the left. Atrial excitation sequence studies demonstrated prolongation of atrial epicardial conduction intervals (2.3 times) between the sinus node and distal right atrial wall. The presence of an interatrial conduction mechanism (whether by specific pathways or not), through which sinus node excitation was transmitted to the A-V node was demonstrated.

Animals↗
PubMed1979

Variable effect on peripheral blood leucocytes during JE virus infection of man.

The peripheral blood leucocytes of twenty-four cases of Japanese encephalitis (JE) were studied and the findings were compared with those in twenty-five normal health controls of matching age and sex. In the early phases of the disease marked neutrophil leucocytosis was seen which returned to almost normal levels by the fourth week. Lymphopenia was associated with diminished T lymphocytes but the number of B lymphocytes remained within the normal range. Though the number of T lymphocytes was reduced, their function of leucocyte migration inhibition in the presence of JE virus antigen was significantly higher. The phagocytic activity of the neutrophils, as shown by the uptake of neutral red dye, was diminished but the phagocytic activity of monocytes as shown by the uptake of neutral red dye, was diminished but the phagocytic activity of monocytes as shown by the uptake of neutral red dye or ingestion of latex particles remained unaffected. HI antibodies against JE virus were significantly higher in cases of encephalitis as compared with the control group. Thus, JE virus infection in man has a variable effect on different components of the peripheral blood leucocytes.

Adolescent↗
PubMed1996

[SMC proliferation and its distribution in autologous vein grafts].

SMC proliferation in intimal hyperplasia is a major cause of graft failure. We induced experimental jugular vein to aortic autograft in 120 Wistar rats, and analyzed the SMC proliferation and its distribution in the graft by flow cytometry (FCM) and immunohistochemistry of proliferating cellular nuclear antigen (PCNA) from 2 hours, 6 hours, 24 hours to 1 week, 2 weeks and 4 weeks. Although the number was not apparently increased in autologous vein graft at early stage, SMC proliferation had started. At 1 week after transplantation, the activity of SMC proliferation increased to a maximum, and returned to baseline level 4 weeks. At early stage, the distribution of SMC proliferation located in the media, but at middle stage, both intima and media all presented a relatively higher proliferative activity. The intima formation occurred by the migration of a large population and the proliferation of a relatively small subpopulation of SMC. Therefore, control of SMC proliferation, and migration of autologous vein grafts must be within two weeks after transplantation.

Animals↗
PubMed1996

Upper gastrointestinal motor activity in patients with slow-transit constipation. Further evidence for an enteric neuropathy.

Recent evidence indicates that patients complaining of severe chronic idiopathic constipation may have motor abnormalities not limited to the colon. We studied by manometric means gastric and small bowel motility in a homogeneous group of patients with chronic idiopathic constipation, ie, the slow transit type. Twenty-one patients were recruited for the study and compared to 33 healthy subjects. Manometric examination was carried out for about 5 hr fasting and 1 hr after a standard meal. Analysis of the manometric tracings revealed during fasting no abnormalities in number and configuration of migrating motor complex with respect to controls. However, in 70% of patients motor abnormalities were detected, represented by bursts of nonpropagated contractions and discrete clustered contractions. After feeding, the patient group displayed a significantly shorter antral motor response to the meal with respect to controls; moreover, intestinal bursts of nonpropagated contractions were found in 19% of patients, and 14% of them had an early return of the activity fronts. We conclude that patients with slow transit constipation frequently display motor abnormalities of the upper gut. These findings further strengthen the concept that this condition may represent a panenteric disorder.

Adult↗
PubMed2001

Macrophage migration inhibitory factor up-regulates matrix metalloproteinase-9 and -13 in rat osteoblasts. Relevance to intracellular signaling pathways.

Neutral matrix metalloproteinases (MMPs) play an important role in bone matrix degradation accompanied by bone remodeling. We herein show for the first time that macrophage migration inhibitory factor (MIF) up-regulates MMP-13 (collagenase-3) mRNA of rat calvaria-derived osteoblasts. The mRNA up-regulation was seen at 3 h in response to MIF (10 microg/ml), reached the maximum level at 6-12 h, and returned to the basal level at 36 h. MMP-13 mRNA up-regulation was preceded by up-regulation of c-jun and c-fos mRNA. Tissue inhibitor of metalloproteinase (TIMP)-1 and MMP-9 (92-kDa type IV collagenase) were also up-regulated, but to a lesser extent. The MMP-13 mRNA up-regulation was significantly suppressed by genistein, herbimycin A and 4-amino-5-(4-chlorophenyl)-7-(t-butyl)pyrazolo[3,4-d]pyrimidine. Similarly, a selective mitogen-activated protein kinase (MAPK) kinase (MEK)1/2 inhibitor (PD98059) and c-jun/activator protein (AP)-1 inhibitor (curcumin) suppressed MMP-13 mRNA up-regulation induced by MIF. The mRNA levels of c-jun and c-fos in response to MIF were also inhibited by PD98059. Consistent with these results, MIF stimulated phosphorylation of tyrosine, autophosphorylation of Src, activation of Ras, activation of extracellular signal-regulated kinases (ERK) 1/2, a MAPK, but not c-Jun N-terminal kinase or p38, and phosphorylation of c-Jun. Osteoblasts obtained from calvariae of newborn JunAA mice, defective in phosphorylation of c-Jun, or newborn c-Fos knockout (Fos -/- ) mice, showed much less induction of MMP-13 with the addition of MIF than osteoblasts obtained from wild-type or littermate control mice. Taken together, these results suggest that MIF increases the MMP-13 mRNA level of rat osteoblasts via the Src-related tyrosine kinase-, Ras-, ERK1/2-, and AP-1-dependent pathway.

Animals↗
PubMed2000

Bilingualism, school achievement, and mental wellbeing: a follow-up study of return migrant children.

In the first phase of this follow-up study we investigated how the use of more than one language affects mental wellbeing and school achievement among 320 school-aged Finnish-Swedish re-migrant children. Now, in the second phase, we screened the same series of children 6 years after migration for psychiatric and psychosomatic symptoms. Out of five groups distinguished in terms of patterns of language use, two had fared well and three showed evident vulnerability. Both successful groups were marked by consistent use of the two languages, Finnish and Swedish, whereas the risk groups were characterised by mixed use of languages before re-migration or substantial language shift after re-migration.

Achievement↗