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At least 577 records · Page 32Linked to original sources
PubMed1999

Role in neuronal cell migration for high-threshold potassium currents in the chicken hindbrain.

We have investigated the influence of voltage-dependent, potassium conductances on the migration of embryonic neurons, using a culture preparation taken from the acoustico-vestibular anlage long before the onset of electrical excitability and synaptic function. Whole-cell patch clamp recordings from migrating neuroblasts at Hamburger-Hamilton stage 28 (E 5.5) revealed the exclusive expression of voltage-dependent, high-threshold, outward currents, activating at potentials positive to -20 mV. These currents were completely suppressed by the potassium channel blockers, 1.0 mM tetraethylammonium chloride (TEA) or 1.0 mM 4-aminopyridine (4-AP). In control media, the active migration of individual neuroblasts was recorded at 27 +/- 6 microm per hr. Within minutes after adding either drug to the culture, normal migration completely stopped for several hours. Calcium channel blockers, omega-conotoxin (3 microM) or cadmium chloride (100 microM), slowed, but did not halt, migration, while nickel chloride (100 microM) or N-methyl-D-glucamine (1 mM) had no effect. However, within 8 hr after TEA exposure, migratory activity usually returned. This recovery was associated with the appearance of a previously undetected, low-threshold and 4-AP- sensitive potassium conductance. We suggest that high-threshold, TEA/4-AP-sensitive potassium channels may normally support the migration of these neurons, while their chronic blockade can be compensated by the appearance of novel potassium channels. Potassium currents may act in concert with N-type calcium channels to regulate neuronal migration.

4-Aminopyridine↗
PubMed1984

Relation of intra-splenic migration of marginal zone B cells to antigen localization on follicular dendritic cells.

Injection of heat-killed Escherichia coli into rats results in massive loss of IgM + ve, IgD - ve B cells from the marginal zones of their spleen within 4 hr. This is matched by a concomitant increase of cells with this phenotype in the splenic follicles. The marginal zone remains depleted and the follicles distended for about 16 hr, but the histological picture returns to normal within 24 hr. Surface marker analysis of blood and spleen B lymphocyte populations throughout the course of the migration suggest that there is intrasplenic migration of IgM + ve cells from marginal zone to follicles rather than via the circulation. Factors inhibiting localization of immune complex on follicular dendritic cells were assessed for their influence on marginal-zone B cell migration. Immune complex, injected 5 hr post-endotoxin administration localized poorly on follicular dendritic cells. While C3 depletion, by cobra venom, has no effect on marginal-zone B cell migration induced by endotoxin, it completely inhibits transport of heat-aggregated human gammaglobulin to follicular dendritic cells.

Animals↗
PubMed1995

Opioid and nonopioid analgesic drug effects on colon contractions in monkeys.

Opioid drugs administered postoperatively for pain relief cause increased frequency of nonpropulsive phasic contractions but decreased to absent propulsive migrating contractions in the colon, thus importantly influencing the duration of postoperative ileus. Ketorolac is thought to permit earlier return of bowel function postoperatively compared to morphine. Four monkeys had sets of three strain gauge force transducers implanted on the right and left colon at laparotomy. After recovery, animals were fasted overnight and had colon contractions recorded. After a 1-hr baseline period, 200 micrograms/kg morphine sulfate or 1 mg/kg ketorolac tromethamine was injected intramuscularly and recording continued. Each animal received four injections of each drug. Records were analyzed visually for frequency of phasic on migrating contractions. There was no difference in the frequency of phasic or migrating contractions after injection of ketorolac. Morphine, as expected, increased the frequency of phasic and decreased the frequency of migrating contractions in the colon. Ketorolac does not affect the frequency of colon contractions.

Analgesics, Non-Narcotic↗
PubMed1999

TNF-alpha-induced migration of vascular smooth muscle cells is MAPK dependent.

-Migration of vascular smooth muscle cells (VSMC) is a key event in neointimal formation and atherosclerosis that may be linked to the accumulation of inflammatory cells and release of chemotactic cytokines. Tumor necrosis factor-alpha (TNF-alpha) induces chemotaxis of inflammatory cells and fibroblasts, but little is known about chemotactic signaling by TNF-alpha in VSMC. The aim of this study was to investigate the role of TNF-alpha in VSMC migration and to elucidate the chemotactic signaling pathways mediating this action. TNF-alpha (50 to 400 U/mL) induced migration of cultured rat aortic VSMC in a dose-dependent manner. Because activation of the extracellular signal-regulated kinase 1/2 mitogen-activated protein kinase (MAPK) is known to be required in platelet-derived growth factor-directed and angiotensin II-directed migration of these cells, we used the MAPK-inhibitor PD98059 to determine if chemotactic signaling by TNF-alpha involves the MAPK pathway as well. We found that TNF-alpha-directed migration was substantially inhibited by PD98059. TNF-alpha (100 U/mL) transiently activated MAPK with a maximal induction 10 minutes after stimulation that returned to baseline levels by 2 hours after treatment. Only a single peak of increased MAPK activity was seen. PD98059 also blocked TNF-alpha-stimulated MAPK activation in a concentration-dependent manner, which is consistent with its inhibition of TNF-alpha-directed migration. To identify which TNF-alpha receptor is involved in TNF-alpha-induced MAPK activation, antibodies against the p55 TNF-alpha receptor-1 (TNF-R1) and the p75 TNF-alpha receptor-2 (TNF-R2) were used. VSMC express both receptors, but TNF-alpha-induced MAPK activation was inhibited only by the TNF-R1 antibody. The TNF-R2 antibody had no effect. Thiazolidinediones are known to inhibit TNF-alpha signaling in adipose tissue and attenuate platelet-derived growth factor-directed and angiotensin II-directed migration in VSMC. We therefore investigated the effects of the thiazolidinediones troglitazone (TRO) and rosiglitazone (RSG) on TNF-alpha-induced migration. Both TRO and RSG inhibited migration, but neither attenuated TNF-alpha-induced MAPK activation, indicating that their antimigration activity was exerted downstream of MAPK. These experiments provide the first evidence that early activation of MAPK is a crucial event in TNF-alpha-mediated signal transduction leading to VSMC migration. Moreover, inhibition of TNF-alpha-directed migration by the insulin sensitizers TRO and RSG underscores their potential as vasculoprotective agents.

Analysis of Variance↗
PubMed1985

Unusual position of a chest tube with elevation of the contralateral hemidiaphragm.

We present a patient with emphysema and a right-sided pneumothorax in whom a chest tube was inadvertently positioned in the lower portion of the right major fissure. The tube migrated across the midsaggital plane, resulting in left shoulder pain with elevation of the left hemidiaphragm. Malfunctioning of the tube did not result, and following its removal the diaphragm returned to its original position.

Aged↗
PubMed2003

Clip migration within 8 days of 11-gauge vacuum-assisted stereotactic breast biopsy: case report.

A 49-year-old woman underwent 11-gauge vacuum-assisted stereotactic biopsy of a cluster of indeterminate calcifications in the left breast. A clip was deployed accurately at the biopsy site as confirmed on mammograms obtained immediately after biopsy. The patient returned 8 days later for additional stereotactic biopsies of the left breast. Repeat mammograms revealed that the clip deployed at the original biopsy site had migrated 5 cm inferiorly.

Biopsy↗
PubMed1989

Cell-mediated immune responses associated with short term alcohol intake: time course and dose dependency.

Using a rat model, we report here the duration of heavy drinking necessary to produce immunosuppression, the recovery time after such alcohol-induced immunosuppression, and the variations in immune response associated with varied amounts of alcohol consumption. Immune status was evaluated by means of delayed cutaneous hypersensitivity (DCH)-like responses to phytohemagglutinin. The daily consumption of 5 g of ethanol/kg body weight/d resulted in a prompt reduction in DCH-like responses which was significant by Day 3 (p = 0.03) and maximal by Day 11 (45% of baseline). These data were consistent with a similar reduction of migration inhibitory factor activity in spleen cells from ethanol fed rats. Cessation of ethanol resulted in a return to baseline within 4 days. In a second experiment ethanol was administered daily in doses ranging from 0.5 to 6.0 g/kg. Early (Day 5) low dose ethanol (0.5-2 g/kg) stimulated immune response (153-188% of baseline) while high dose (6.0 g/kg) suppressed (79% of baseline). Continued treatments resulted in a loss of stimulation at low dose and increased suppression at higher doses. The relationship of these animal studies to human binge drinking and the possible risk for infection in the alcoholic remains to be established.

Animals↗
PubMed1978

Migration of allied health care personnel in and out of an underserved area: a question of roots.

The distribution of health personnel and the resulting shortages of health care to economically depressed, ethnic, rural and inner city areas is a serious problem. Recruiting students from and training them in underserved areas has been suggested as one way to improve retention rates among graduates of allied health programs. A one-year follow-up survey of 1974 graduates of allied health programs sponsored by an Area Health Education Center located in an underserved, one ethnic group predominant rural area was done to test this approach. Results show that of the 122 graduates surveyed in this study, one year after graduation 85% had returned to work in the area of their previous residence. Among professional groups, licensed vocational nurses experienced the least migration. Generally, professions requiring higher levels of education showed higher relocation rates. Sex and ethnicity were related to these findings. The appeal of higher salaries or material benefits alone did not appear to attract graduates to migrate. It appears that communities with shortages of health manpower due to maldistribution may be successful in correcting this problem by recruiting students from their own area. Possible explanations and recommendations related to these findings are discussed.

Allied Health Personnel↗
PubMed1992

The role of cell proliferation and migration in the development of a neo-intimal layer in veins grafted into arteries, in rats.

The development of a thickened (hyperplastic) fibro-cellular neo-intima is a significant event in the adaptation of a vein grafted into an artery. The histogenesis of tissues in vein grafts was explored in a rat model where the source of endothelial and smooth muscle cells was from the adjacent artery. Cell proliferation was assessed by the incorporation of tritiated thymidine and autoradiography, up to 18 months after grafting. Cell migration was detected by prelabelling in the first 5 days after grafting and sampling at later times. The proliferation of cells in the arterial media adjacent to the graft was elevated above control levels as early as 2 days after grafting; it was maximal at 3 days and returned to low levels by day 21. During the first week, prelabelled smooth muscle cells in the tunica media of the adjacent artery migrated to the subendothelial space, where they continued to proliferate to produce arterial intimal hyperplasia. The migration of endothelial and smooth muscle cells proceeded across the anastomosis to populate the vein graft neo-intima, where smooth muscle cells continued to proliferate until 28 days after grafting. Cell migration and proliferation were significant factors in the histogenesis of vein graft neo-intimal hyperplasia in this model. These processes were controlled, perhaps by local regulatory factors, to form a vein graft, the wall of which was similar in thickness and structure to that of the host artery.

Animals↗
PubMed1999

Patterns of center of presure migration during prolonged unconstrained standing.

Prolonged (>30 min) unconstrained standing (PUS) was studied in 10 young healthy subjects. The usual methods of stabilographic analysis assume a random center of pressure (COP) migration. This study was based on the opposite idea and showed that during PUS, specific and consistent patterns of the COP migration can be recognized by a computer algorithm. Three COP migration patterns were found: (a) shifting, a fast displacement of the average position of COP from one region to another; (b) fidgeting, a fast and large displacement and returning of COP to approximately the same position; and (c) drifting, a slow continuous displacement of the average position of COP. A software code was written and default parameter values were chosen for recognizing COP migration patterns. For 30-min PUS the following patterns were identified: Shifting was generally observed every 316 +/- 292 sec in the anterior-posterior (a-p) direction with an average shift amplitude of 17 +/- 15 mm, and every 199 +/- 148 sec in the medial-lateral (m-l) direction with an average shift amplitude of 22 +/- 38 mm. Corresponding time intervals for fidgeting were 59 +/- 15 sec in the a-p direction and 49 +/- 16 sec in the m-l direction. The average drift-to-drift interval was 319 +/- 173 sec in the a-p direction and 529 +/- 333 sec in the m-l direction.

Adult↗
PubMed1981

Measuring interstate migration flows: an origin-destination network based on Internal Revenue Service records.

"This paper examines gross interstate migration flows for five periods for the years between 1969 and 1978. The analysis is based upon a newly available data source--Federal income tax returns. Approximately 90% of the US population is covered by this data series. The matching of Internal Revenue Service (IRS) returns between filing dates enables the determination both of the origin and of the destination of migrants, with few of the risks of geographic miscoding present. "These data illustrate that despite divergent economic fluctuations over the past nine years, the patterns of interstate migration have remained virtually unchanged. With few exceptions, the number of migrants either leaving or entering a particular state comprise identical proportions over time.... In addition, these data offer considerable evidence that current residence has a significant impact on the selection of a destination." Comparisons are made with data from the Current Work History Sample and the 1970 census.

Americas↗
PubMed1991

Orientation in birds. Magnetic orientation and celestial cues in migratory orientation.

Young birds on their first migration possess innate information on the direction of their migration route. It is represented twice, using both celestial rotation and the geomagnetic field as references. These two systems, together with information provided by factors associated with sunset, interact in a complex way to establish the migratory direction. During ontogeny, celestial rotation appears to be dominant; during migration, however, celestial cues appear to be controlled by the magnetic field.--The factors associated with sunset--the view of the setting sun and the characteristic pattern of polarized light--are important secondary cues which seem to derive their directional significance from the magnetic field. Their role appears to be more variable, with possible species-specific differences. During spring migration and later autumn migrations, flying in the migratory direction is complemented by navigational processes which enable the birds to return to a specific home site known from previous stays.

Animals↗
PubMed1985

Reconstruction of the horizontal palpebral aperture after failed ectropion surgery with temporal migration of punctum.

Involutional ectropion of the lower lid is the result of progressive stretching and elongation of the lid margin and medial and lateral canthal tendons. The relative laxities of the components of the lower lid-canthal tendon complex will determine the location and extent of the ectropion. Whereas inadequate canthal tightening or horizontal lid shortening will result in recurrent ectropion, overzealous lid shortening without tendon plication will result in a noticeably narrower horizontal palpebral fissure, a persistent ectropion, or temporal migration of the punctum. We used lateral cantholysis, medial canthal tendon plication, and punctal rotation to return the punctum to its normal position and temporalis muscle to support the lower lid in eight cases in which previous procedures had failed to correct the lid malposition. In all eight cases there was improvement of the lid position. In one case of severe medial ectropion, the punctal eversion was not completely corrected. This technique is not recommended as an initial procedure for ectropion repair. It is only used to manage previous surgical failures. It is a new application and combination of well-accepted techniques.

Aged↗
PubMed2005

Migration and mental health in Europe (the state of the mental health in Europe working group: appendix 1).

BACKGROUND: This paper is a part of the work of the group that carried out the report "The state of the mental health in Europe" (European Commission, DG Health and Consumer Protection, 2004) and deals with the mental health issues related to the migration in Europe. METHODS: The paper tries to describe the social, demographical and political context of the emigration in Europe and tries to indicate the needs and (mental) health problems of immigrants. A review of the literature concerning mental health risk in immigrant is also carried out. The work also faces the problem of the health policy toward immigrants and the access to health care services in Europe. RESULTS: Migration during the 1990s has been high and characterised by new migrations. Some countries in Europe, that have been traditionally exporters of migrants have shifted to become importers. Migration has been a key force in the demographic changes of the European population. The policy of closed borders do not stop migration, but rather seems to set up a new underclass of so-called "illegals" who are suppressed and highly exploited. In 2000 there were also 392,200 asylum applications. The reviewed literature among mental health risk in some immigrant groups in Europe concerns: 1) highest rate of schizophrenia; suicide; alcohol and drug abuse; access of psychiatric facilities; risk of anxiety and depression; mental health of EU immigrants once they returned to their country; early EU immigrants in today disadvantaged countries; refugees and mental health. Due to the different condition of migration concerning variables as: motivation to migrations (e.g. settler, refugees, gastarbeiters); distance for the host culture; ability to develop mediating structures; legal residential status it is impossible to consider "migrants" as a homogeneous group concerning the risk for mental illness. In this sense, psychosocial studies should be undertaken to identify those factors which may under given conditions, imply an increased risk of psychiatric disorders and influence seeking for psychiatric care. COMMENTS AND REMARKS: Despite in the migrants some vulnerable groups were identified with respect to health problems, in many European countries there are migrants who fall outside the existing health and social services, something which is particularly true for asylum seekers and undocumented immigrants. In order to address these deficiencies, it is necessary to provide with an adequate financing and a continuity of the grants for research into the multicultural health demand. Finally, there is to highlight the importance of adopting an integrated approach to mental health care that moves away from psychiatric care only.

Journal Article↗
PubMedDate not supplied

[Protein changes in the jejunal juice and endointestinal exudation of albumin-I 131 in acute infectious enterocolitis].

The phenomenon of endointestinal protein exudation in acute infectious enterocolitis is studied. Total proteins were determined in 30 cases of acute enterocolitis and 50 of bacillary dysentery in the acute stages of the disease and convalescence. The proteinogram of the jejunal juice was performed in the acute stage and convalescence in 20 patients. In 16 patients and 5 controls endointestinal albumin elimination was determined quantitatively by means of 131I labeled albumin. The results showed increase in the total protein content in the jejunal juice in the course of acute infectious enterocolitis and bacillary dysentery and a return to normal values in convalescence. Electrophoresis of the jejunal juice in acute infectious enterocolitis showed the absence of fraction III with alpha1-globulin migration, and increased fractions I, II and IV probably due to the loss of endointestinal albumin, also confirmed by quantitative albumin determinations with 131I labeled albumin. In conclusion, patients with acute infectious enterocolitis present a marked loss of endointestinal albumins in the acute stage of the disease, with a return to normal values in convalescence.

Albumins↗
PubMed1994

Adaptation to a new world: experience of Bangladeshis in Japan.

The author explores aspects of Bangladeshi migration to Japan. "The information base for the study is two major sources: sections on the level and trend of migration, socio-economic characteristics of migrants and their job experiences in Japan are based on a survey of Bangladeshi returned migrants from Japan. Information on their socio-economic adjustment was obtained from personal interviews with migrants who had lived and worked in Japan." (SUMMARY IN FRE AND SPA)

Acculturation↗
PubMed1981

Molecular forms of rat brain acetylcholinesterase in DFP intoxication and subsequent recovery.

The effects of acute administration of diisopropyl fluorophosphate, Isofluorophate (DFP) 1.1 mg/kg SC on soluble brain acetylcholinesterase were studied in male Sprague-Dawley rats sacrificed at time intervals ranging from 3 hr to 25 days. Three main molecular forms of AChE were separated by polyacrylamide gel electrophoresis followed by enzymatic reaction with acetylthiocholine, staining and scanning densitometry for their quantitative evaluation. In some experiments the same three forms were separated by chromatography-gel filtration. In the brain of untreated animals the slowly-, medium- and fast-migrating forms accounted respectively for 64, 18 and 18% of the soluble AChE activity. At 3 hr after treatment with DFP, resulting in an 80% reduction of soluble AChE, the relative contribution of slowly-migrating forms to the residual enzymatic activity was decreased, while that of medium-forms was significantly increased. These changes became gradually more pronounced and reached their maximum at 4 days, when AChE had recovered to about 50% of control level. Subsequently, the distribution of the molecular forms showed a progressive return toward the control pattern. The partial recovery in the initial period after maximal enzyme depression was mainly due to an increase of medium-migrating forms. Thus these may be precursors of the biosynthesis of slowly-migrating forms and/or there may be functional specialization of different forms.

Acetylcholinesterase↗
PubMed1984

Temporal response of murine bone marrow to local hyperthermia.

Hemopoietic insufficiency resulting from single or multiple agents used in cancer therapy often becomes a dose limiting toxicity. Since hyperthermia is finding increased clinical application with whole body or extended field treatments for a variety of neoplastic diseases, we wished to examine its potential effects on normal bone marrow. One hind leg of anesthetized mice received up to one hour water bath heating to 41-44 degrees C. With temperatures of 42 degrees C or greater, there was a dose and heating time dependent initial depletion of both CFU-S and CFU-GM that was not appreciably affected by migration of stem cells to or from the heated field. CFU-S and CFU-GM returned to normal values by 2 to 3 weeks after 1 hour heating to 42 degrees C. However, at 43 degrees or 44 degrees C for 1 hour, CFU-GM only transiently returned to normal, falling to 55% and 33% of control respectively by 3 months. Total nucleated cell counts reflected a similar dose and time dependent depletion and repopulation. Finally, bone marrow differential counts from heated marrow suggested that equivalent repopulation along each differentiation pathway occurred during recovery after thermal injury. These data indicate that temperatures greater than 42 degrees C for one hour caused a long term delay in hemopoietic repopulation, which may contribute to a significant toxicity when hyperthermia is used in combination with chemotherapeutic drugs or local irradiation incorporating the same treatment field.

Animals↗