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PubMed1981

Anthelmintic treatment of prepatent stephanuriasis with flubendazole, levamisole and disophenol and the effects on liver-specific serum enzymes.

Haematological parameters and liver specific serum enzymes were examined in pigs during the first 12 weeks of liver migration of larvae following experimental infection with 1000 infective Stephanurus dentatus larvae. No significant changes in total red blood cell counts, packed cell volume, or haemoglobin content were observed. Total white blood cell counts and circulating eosinophils rose rapidly from days 5 and 19 after infection, respectively. Treatment with a mixture of levamisole (LEV) at 10 mg/kg and flubendazole (FLU) at 50 mg/kg in feed four weeks after infection halted the leucocyte response and returned values to normal in two weeks. Disophenol (DIP) at 15 mg/kg subcutaneously restricted the leucocyte response but it was only terminated following FLU treatment alone on day 61. No effects of S dentatus or either anthelmintic treatments on liver specific serum enzymes glutamate dehydrogenase, sorbitol dehydrogenase or gamma-glutamyl transpeptidase were found. Animals killed seven, 26 and 54 days after treatment showed significant resolution of fibrotic liver lesions after LEV + FLU but not after DIP. We conclude that LEV + FLU is an effective treatment for prepatent stephanuriasis but that liver damage is insufficiently traumatic to release sufficient enzymes into serum to be pathognomonic or to assess anthelmintic efficacy.

Animals↗
PubMed1983

The migration of lymphocytes across specialized vascular endothelium. VI. The migratory behaviour of thoracic duct lymphocytes retransferred from the lymph nodes, spleen, blood, or lymph of a primary recipient.

Thoracic duct lymphocytes labelled with 51Cr were injected into a primary recipient and then were transferred for a second time from the lymph nodes (cervical and/or mesenteric), spleen, lymph, or blood into a series of final recipients. Measurement of the organ distribution of labelled lymphocytes in the final recipients enabled three main conclusions to be drawn. (1) Lymphocytes that had localized in the spleen, mesenteric lymph nodes (LN), or cervical LN of the first recipient showed no tendency to return in increased numbers to the same organ in the final recipient. (2) Lymphocytes that had recently entered the spleen or LN were temporarily impaired in their ability to reenter LN. This capacity was recharged when the cells returned to the lymph and the blood. (3) Lymphocytes that had been passaged from blood to lymph and collected for up to 4 hr at room temperature entered the LN of a recipient much faster than did nonpassaged thoracic duct lymphocytes collected overnight at 0 degree C. Supplementary experiments indicated that the different migratory behavior of thoracic duct lymphocytes under these two circumstances was mainly a consequence of their handling in vitro during the collecting and the labelling procedures. This functional impairment was not associated with a diminished ability to enter the spleen and bone marrow or to survive in recipients for up to 24 hr.

Animals↗
PubMed1984

Time course of the spasmolytic effect of cadmium and cadmium uptake in guinea-pig taenia coli.

The relationship between tension inhibitory action of cadmium and cadmium uptake was investigated in the smooth muscle of taenia coli. Following a treatment with 0.5 mM Cd2+ for short periods (1, 5 min), the tension to high-K+ returned to a greater extent after washing with disodium edetate (EDTA) or cysteine, compared to normal medium. However, the restored tension to the high-K+ decreased with increasing duration of Cd2+ treatment. With a longer duration of 0.5 mM Cd2+ treatment, the cadmium uptake increased and the size of cadmium fraction bound to cells firmly increased. It is suggested that Cd2+ binds initially to the surface membrane of taenia coli and that Cd2+ subsequently migrates to a compartment that EDTA cannot reach.

Animals↗
PubMed2003

Photoperiodic response may facilitate adaptation to climatic change in long-distance migratory birds.

Recent climatic change is causing spring events in northern temperate regions to occur earlier in the year. As a result, migratory birds returning from tropical wintering sites may arrive too late to take full advantage of the food resources on their breeding grounds. Under these conditions, selection will favour earlier spring arrival that could be achieved by overwintering closer to the breeding grounds. However, it is unknown how daylength conditions at higher latitudes will affect the timing of life cycle stages. Here, we show in three species of Palaearctic-African migratory songbirds that a shortening of migration distance induces an advancement of springtime activities. Birds exposed to daylengths simulating migration to and wintering in southern Europe considerably advanced their spring migratory activity and testicular development. This response to the novel photoperiodic environment will enable birds wintering further north to advance spring arrival and to start breeding earlier. Thus, phenotypic flexibility in response to the photoperiod may reinforce selection for shorter migration distance if spring temperatures continue to rise.

Acclimatization↗
PubMed1980

Sequential evaluation of immunoreactivity in patients with melanoma undergoing surgery and adjuvant therapy.

The immunologic profile of 15 patients undergoing surgery and adjuvant chemoimmunotherapy for cutaneous melanoma was studied for a mean period of 18 months. In vivo cellular immunity was assayed by evaluation of delayed hypersensitivity response (DHR) to primary antigen and a panel of recall antigens. In vitro cellular immunity was evaluated to means of total and T-lymphocyte counts in peripheral blood and by the lymphocyte blastogenic response to phytohemagglutinin stimulation. Humoral immunity was assayed by determining the serum levels of IgG, IgA and IgM and of complement components C3c, C4 and Factor B. Phagocytic activity was studied by testing leukocyte chemotaxis, neutrophil phagocytosis and leukocyte random migration. The in vitro parameters were determined preoperatively at diagnosis, 6 times during the first 2 postoperative weeks, and then every month during adjuvant therapy. No correlation was found between DHR and clinico-pathologic stage of tumor, or with subsequent clinical course. Significant depression of total lymphocyte and T-lymphocyte count and blastogenic response of lymphocytes was found at diagnosis. The lymphocyte response to PHA decreased significantly in the early postoperative period but returned to preoperative levels one week after surgery. Periodic fluctuations of lymphocyte blastogenic response and progressive decrease of total lymphocyte counts and T-lymphocyte counts were observed during the 18-month follow-up. No significant alterations of immunoglobulin levels were recorded at diagnosis or during the postoperative period. Complement levels were within normal values preoperatively; in the early postoperative period a transient increase of C3c, C4 and Factor B was recorded, then complement levels progressively decreased. Parameters of phagocytic activity were normal at diagnosis and fluctuated within the normal range throughout the whole period of study.

Adult↗
PubMed1998

Effect of a magnetic pulse on the orientation of silvereyes, zosterops l. lateralis, during spring migration

The orientation behaviour of Australian silvereyes, Zosterops l. lateralis, was tested during their spring migration, when they head southward to their Tasmanian breeding grounds. With only the local geomagnetic field as a cue, the birds significantly preferred their normal southerly migratory direction. Treatment with a short, strong magnetic pulse designed to alter the magnetization of single-domain magnetite led to a significant deflection towards the east for the next 4 days. This was followed by a period of non-oriented behaviour. From day 10 onwards, the birds returned to their original southerly headings. Together with previous findings, these data suggest that the navigational 'map' of these birds includes magnetic parameters and that a magnetite-based receptor provides them with information about their position. The transient nature of the effect is not easily explained on the basis of single-domain magnetite.

Journal Article↗
PubMed2001

[Effect of chemical sympathectomy on myoelectric activity of the small bowel].

UNLABELLED: Central and peripheral noradrenergic system modulates myoelectric activity of the small bowel. Aim of this study was to evaluate the role of peripheral noradrenergic system in modulation of slow waves activity. Recordings of slow waves were performed on 20 conscious rats chronically fitted with 2 unipolar electrodes. After controls recording the animals were injected i.p. with 6-hydroxydopamine (6-OHDA--Sigma H8523) and the recording were performed on daily basis through the period of one month. RESULTS: The increase of frequency slow waves during the first week after 6-OHDA from 0.61 (+/- 0.11) to 0.71 (+/- 0.03), (p. < 0.05), and amplitude from 14468 +/- 11196 to 19128 +/- 5282 (microV)2 (p > 0.05) were observed. Variability in control recording was higher (SD +/- 0.11) than after 6-OHDA (SD 0.03). Next day diarrhoea after 6-OHDA occurred, persisted despite return normal myoelectric activity. Slow waves frequency gradually returns to control value after the fourth week. CONCLUSION: Peripheral noradrenergic system has a significant effect on the frequency and variability of slow wave and minor role on its amplitude but no on diarrhoea pattern.

Animals↗
PubMed2004

Microglial responses in the avascular quail retina following transection of the optic nerve.

This study was undertaken to investigate microglial responses in the avascular central nervous system using the quail retina that is known to be devoid of blood vessels. Following intraorbital optic nerve transection (ONT), the quail retina was examined immunohistochemically at various times up to 6 months. A few days after transection, microglia in the inner retinal layers revealed features of activation. Activated cells displayed an amoeboid shape and enhanced QH1-immunoreactivity. The numbers of these amoeboid cells were rapidly increased, first in the inner plexiform layer (IPL), and then in the ganglion cell/nerve fiber layer (GCL/NFL) of the retina where retrograde degenerating ganglion cell processes and perikarya were located. By 6 months after transection, microglia regained their resting morphology, and their cell counts returned to control levels. At early time points of microglial activation, numerous QH1+ amoeboid cells were observed along the vitreal surface of the pecten and retinal region adjacent to the insertion of the pecten, where some amoeboid cells were attached underneath the internal limiting membrane, and appeared to squeeze through the optic nerve fiber bundles. A considerable number of these amoeboid cells in the GCL/NFL and the IPL were labeled with PCNA, suggesting that active exogenous migration (from the pecten) and in situ proliferation of precursor cells contribute to the increase in microglial population of the degenerating retina. On the other hand, TUNEL-positive microglia appeared in the GCL/NFL at later time points indicate that the decrease of microglial numbers is in part due to apoptosis in these layers. Although some aspects of microglial activation in the avascular retina appear unique, their consequences were similar to those described in vascular retinae of mammals, a finding indicates that blood vessels are not a prerequisite for microglial activation, and microglial precursors could migrate long distance to reach the lesioned site, which is not accessible via blood vessels. Our data provide the first analysis of microglial activation in the avascular central nervous system (CNS), and suggest that the quail retina is a useful model for studies of microglial behavior in CNS.

Animals↗
PubMed1999

Increased secretion of basement membrane-degrading metalloproteinases in pig saphenous vein into carotid artery interposition grafts.

Late saphenous vein bypass graft failure in humans involves medial and neointimal thickening as the result of migration and proliferation of vascular smooth muscle cells (SMCs). Recent work on angioplasty indicates that basement membrane-degrading metalloproteinases (MMPs) cooperate with growth factors to mediate SMC migration and proliferation. We sought evidence here for a similar role in experimental vein grafts in pigs. Tissue levels and secretion of MMP-2 and MMP-9 were compared by quantitative zymography in veins and grafts removed 2 to 168 days after implantation. Pro and active forms of MMP-2 were present in veins, but levels were increased in vein grafts after 7 days (4- and 6-fold, respectively) and 28 days (3-fold for both), returning to values in veins after 168 days. MMP-9 was not detected in veins, was increased in grafts after 2 days, further increased after 7 days (6-fold) and 28 days (15-fold), and declined to undetectable levels by 168 days. Immunocytochemistry detected increased expression of MMP-2 and MMP-9 with the same time course. MMP-2 was widely distributed, whereas MMP-9 was concentrated in highly proliferative SMCs at the superficial layers of the thickened neointima. We conclude that increased production of the basement membrane-degrading MMP-2 and MMP-9 spanned the period of neointima formation and SMC proliferation in experimental vein grafts. MMPs therefore constitute new therapeutic targets for reducing late vein graft failure.

Animals↗
PubMed2006

Fear of sexually transmitted infections among women with male migrant partners -- relationship to oscillatory migration pattern and risk-avoidance behaviour.

BACKGROUND: In South Africa, former apartheid laws encouraged rural males seeking employment to migrate to urban areas, moving weekly, monthly or annually between their rural families and urban workplaces. The combination of the migrant labour system and long family separations caused an explosion of serious health consequences, among others sexually transmitted infections (STIs) in the migrant population. OBJECTIVE: To describe some correlates of male migration patterns for the rural women left behind, especially the fear of STIs that this engendered in them and their risk-avoidance behaviour. Setting and subjects. In KwaZulu-Natal, 208 prenatal patients who were partners of oscillating male migrant workers were interviewed to determine their demographic and behavioural characteristics, and their fear of STIs. RESULTS: Thirty-six per cent of the rural women said that they were afraid of contracting STIs from their returning migrant partners. Women who saw their partners infrequently were more fearful of STI transmission, and were less able to have sexual communication. However, almost none of the women protected themselves, while only 8% used condoms, primarily for contraceptive purposes. CONCLUSIONS: These results reflect the gender-based power relationships of South African male migrants and their rural partners, the social and economic dependency of the women on their migrant partners, and the women's social responsibility to bear children. The results point to the need to go beyond interventions that simply seek to modify behaviour without altering the forces that promote risk taking and discourage risk reduction, and the need to develop appropriate interventions to curb STIs and decrease HIV.

Adolescent↗
PubMed2006

Circulating ghrelin levels after food intake during different phases of the migrating motor complex in man.

BACKGROUND: The timing of the migrating motor complexes (MMC) at food intake may influence gastric emptying and release of regulatory hormones. This report studies the relationships between phases I (motor quiescence) and II (intermediate frequency contractions) of MMC and prandial gut hormone response. MATERIALS AND METHODS: Seven fasting volunteers ingested a meal during phase I or II of MMC verified by manometry, using paracetamol as a marker for gastric emptying. Blood was sampled before, during and 210 min after food intake for analysis of ghrelin, motilin, insulin and paracetamol. RESULTS: The basal level of ghrelin during phase I was 127.5 +/- 25.4 pmol L(-1) and during phase II was 132.4 +/- 24.8 pmol L(-1). After food intake during phase I, ghrelin fell to 77.2 +/- 10 pmol L(-1); in phase II it fell to 82.7 +/- 17.8 pmol L(-1) within 60 min and returned to baseline levels after 120 min. Baseline levels of motilin were 16 +/- 2 pmol L(-1) and 18 +/- 3 pmol L(-1) during phases I and II, respectively. After food, motilin decreased to 8.5 +/- 0.7 pmol L(-1) and 8.7 +/- 1.0 pmol L(-1) within 60 min and returned to baseline after 90 min. Insulin levels in phases I and II were 8.1 +/- 1.2 mU L(-1) and 8.6 +/- 0.7 mU L(-1), respectively, reaching 138.9 +/- 35.6 mU L(-1) and 167.4 +/- 30.0 mU L(-1) at 45 min postprandially. CONCLUSIONS: The nutritional status of the gastrointestinal tract at food intake had only a limited impact on plasma ghrelin. After food intake, plasma ghrelin drops, similar to motilin, and resumes preprandial levels within 120 min.

Acetaminophen↗
PubMed1992

Time course of permeability changes and PMN flux in rat trachea following O3 exposure.

Changes in rat tracheal epithelial permeability and polymorphonuclear leukocyte (PMN) populations during a 24-hr time period following a 3-hr exposure to 0.8 ppm ozone (O3) were investigated. An increase in permeability to 99mTc-diethylene-triaminepentaacetate (DTPA) occurred immediately after the exposure, peaked at the 8-hr time point and decreased to control level by 24 hr. For correlation with tracheal permeability, tracheal cross sections were stained with naphthol AS-D chloroacetate and PMNs were scored by their location as well as staining characteristics (positive or negative). The total PMN population remained at the control value at the 0-, 4-, and 8-hr time points, and increased at 12 hr, followed by a rapid decline to below the control value for the remaining time points. There was a shift at the 8-hr time point in the population location, from the vasculature to the interstitium, which returned to control values at 12 hr. The percentage stained PMNs increased significantly at 16 hr while remaining at control values for all other time points. The data reveal that there is a significant increase in tracheal epithelial permeability immediately after the exposure, but the overall increase in the PMN population is preceded by a lag phase. A decrease in the vascular pool of PMNs concomitant with an increase in the interstitial pool of PMNs suggests their migration from blood to the interstitium after ozone exposure. These data indicate that while PMNs may play a role in permeability changes of tracheal epithelium, the initiation is most likely due to other factors.

Animals↗
PubMed2002

Dying away from home: quandaries of migration for elders in two ethnic groups.

OBJECTIVES: The purpose was to examine how Cambodian Americans and Filipino Americans view their homeland in old age and how those views affect the contemplation of death, using a multifaceted theoretical framework that encompasses transnationality, place, ethnic identity, continuity, and cultural phenomenology. METHODS: Three in-depth interviews over a 1-year period were conducted with 126 respondents (48 Cambodian Americans and 78 Filipino Americans). Both open-ended and semistructured questions were asked to determine how respondents viewed their eventual deaths. RESULTS: Many Cambodian Americans and Filipino Americans expressed a desire to die in their homelands. Whether or not they desired to return to the homeland to die was mediated by the presence or absence of the extended family, memories of the homeland, and the availability of traditional ritual practices in the United States. DISCUSSION: The preoccupation of respondents with where to die apparently reflects the desire to create continuity in their lives. In their efforts to reconcile issues of continuity, cultural meanings surrounding memory, ritual, and the family were paramount and appeared to reflect a desire to bring closure to unresolved conflicts in their lifetime. This research, including its theoretical framework, has implications for using the concept of transnationality and related concepts in gerontological research.

Aged↗
PubMed2003

Role of matrix metalloproteinases in asthma.

Airway inflammation and remodeling are key features of asthma. Matrix metalloproteinases (MMPs) and their inhibitors, tissue inhibitors of metalloproteinases (TIMPs) are thought to contribute to the pathogenesis of asthma via their influence on the function and migration of inflammatory cells as well as matrix deposition and degradation. TIMPs bind MMPs in a 1:1 fashion. Thus, an increase in the molar ratio of MMP/TIMP may favor tissue injury, while the reverse could be associated with increased fibrosis. MMP-9 is the predominant MMP in asthma, and its expression is enhanced when patients have spontaneous exacerbations or in response to local instillation of allergen in the airway. As acute inflammation resolves, MMP-9 levels return toward normal. Interestingly, corticosteroids downregulate MMP and enhance TIMPs. Even though it is clear that enhanced airway inflammation in asthma is associated with increased expression of MMPs, whether specific inhibitors of MMP could reduce airway injury and facilitate orderly healing in asthma is still unknown.

Animals↗
PubMed1989

Population growth and economic development: a case study of Yugoslavia.

The paper deals with the relationship between the population growth and economic development in Yugoslavia and its republics, covering the period after the 2nd World War. Yugoslavia is a developing country with a specific demographic and economic structure which makes it unique in Europe. Its territory is comprised of both relatively developed regions where demographic transition is over, and underdeveloped regions with high natural increase of population where the demographic transition is only just beginning. Correlation and regression methods were used to quantify this relationship. The economic development and structural changes are discussed, relating to human factor. An adequate population policy through family planning is stressed as important in obtaining an increased return to scale with a more positive role of demographic factor.

Birth Rate↗
PubMed1997

Increased endothelin ET(A) receptor expression in rat carotid arteries after balloon injury.

Endothelins are vasoactive peptides and are believed to act as vascular smooth muscle mitogens. Vascular injury results in medial smooth muscle migration and proliferation with the formation of a neointima. Using quantitative autoradiography, we examined the expression of endothelin receptor subtypes ET(A) and ET(B) in the rat carotid artery 2, 8, and 16 days after balloon-catheter injury. At two and eight days after balloon catheterization, ET(A) receptor expression was significantly increased in the media of the injured vessel when compared to that in the media of the intact vessel. The enhanced expression of receptors returned to normal levels by 16 days after the injury. Neointimal cells also expressed ET(A) receptors at a lower level than that expressed by the injured media 8 days after injury, and continued to express ET(A) receptors 16 days after the injury. ET(B) receptors were not detectable in the media or the neointima at any time after the injury. Our results suggest the ET(A) receptors may have a significant role in injury induced vascular smooth muscle proliferation and neointima formation.

Animals↗
PubMed1993

Outcome of Wisconsin instrumentation in idiopathic scoliosis. Minimum 5-year follow-up.

Wisconsin segmental spinal instrumentation was developed by Drummond et al to provide rigid fixation for correction of spinal deformities without the risk of neurologic injury associated with the passage of sublaminar wires. Up to this point, there have been no outcome studies with follow-up of longer than 2 years. Thirty-five patients with adolescent idiopathic scoliosis treated by the Wisconsin procedure between 1984 and 1987 were reviewed by radiographs, physical examination, and an outcome scale. Minimum length of follow-up was 5 years with an average of 6.3 years. Curves were corrected from a mean of 59 degrees preoperatively to 32 degrees postoperatively (46%), and 36 degrees at final follow-up (39%). Wisconsin segmental spinal instrumentation did not increase thoracic kyphosis. There was evidence of slight lumbar flattening in long fusions. According to the criteria described, 92% had a successful outcome. Complications of the procedure included two wound infections (one superficial, one deep), one rod displacement, and two wire breakages. No pseudarthroses or neurologic complications were identified in this series. Wisconsin segmental spinal instrumentation safely achieves the objectives of partial correction, arthrodesis, and early return to function. The technique may still have a role, particularly in the thoracic region, in selective thoracic fusion of King type II curves, rigid curves, and double thoracic curves.

Adolescent↗
PubMed1992

[Linguistic orientation of allophones in Montreal].

"The 1986 census shows that Montrealers whose mother tongue is neither English nor French assimilate to English rather than French at the same rate as [in 1971]. However, divergent trends underlie this overall stability. While the Montreal-born prefer English even more massively than in 1971, French has progressed just as markedly among immigrants, though there is a visible return to English among the latest arrivals." (SUMMARY IN ENG AND SPA)

Acculturation↗