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At least 649 records · Page 36Linked to original sources
PubMed1984

Regulation of neutrophil migratory function in burn injury by complement activation products.

Polymorphonuclear neutrophils were isolated from patients with burn injury and random mobility, chemotaxis in response to C5adesArg (as agarose-activated control serum) and to N-formyl-methionyl-leucyl-phenylalanine (F-Met-Leu-Phe) were assessed. For a group of eight patients identified as not experiencing systemic infection, all three neutrophil migratory functions were observed to fall below control levels, beginning 4 to 6 days following burn injury, and to return to control levels after 21 to 30 days of hospitalization. Over this time the chemotactic differential (distance chemotactic migration-distance random migration) for F-Met-Leu-Phe remained positive, while the chemotactic differential for activated serum became nil after postburn day 4. This temporal, specific loss of a chemotactic response to activated serum was associated with rises in immunoreactive plasma C3a and C5a. This pattern of loss of chemotactic function was associated with a selective loss of C5a but not F-Met-Leu-Phe binding activity. These results demonstrate that burn injury can alter neutrophil migratory functions generally, and specifically depress chemotactic responsiveness to activated serum. The mechanism of the latter phenomenon appears to be related to desensitization of circulating neutrophils to C5a due to complement activation.

Adolescent↗
PubMed1989

High and low doses of luteinizing hormone induce different changes in testicular microcirculation.

To study the effects of LH on total testicular blood flow and microcirculation, rats were treated with 2.5 or 25 micrograms LH sc and measurements were made on control rats and on LH-treated rats 1, 2, 3, 4, 6 and 12 h, after treatment. After treatment with 25 micrograms LH, total testicular blood flow, as measured with the radioactive microsphere method, was decreased at 6 h and increased at 12 h. Testicular microcirculatory blood flow was recorded with laser Doppler flowmetry and regular oscillations in blood flow, vasomotion, was observed in control rats. Vasomotion was not present 4 and 6 h after treatment with 25 micrograms LH, but returned at 12 h. Prior to and concomitantly with these changes in vasomotion, polymorphonuclear leukocytes accumulated in testicular microvessels and migrated into the interstitial tissue. These changes were followed, 6 h after treatment, by an increased vascular permeability, measured as increased testicular interstitial fluid volume. The lower dose of LH (2.5 micrograms), doubled plasma testosterone concentration and initially decreased interstitial fluid volume, and later induced a slight increase in blood vessel leukocytes. At the times studied, no changes could be observed in the other vascular parameters. In conclusion, it is suggested that LH, probably via some Leydig cell product, promotes regulatory effects on testicular microcirculation, but different magnitudes of LH stimulation induce different responses.

Animals↗
PubMed1999

Comparison of first carpometacarpal joint arthrodesis with contralateral excision arthroplasty in a patient with bilateral saddle joint arthritis: a case report.

A post-menopausal patient with bilateral primary osteoarthritis of the first carpometacarpal joint (CMCJ) was treated by 2 different surgical techniques. The non-dominant left CMCJ was arthrodesed in 1992 while excision of trapezium and tendon suspensionplasty was done for the dominant right side in 1997. She reported good pain relief with both procedures and she was able to fully oppose both thumbs at 6 years after arthrodesis and 1 year after arthroplasty. The grip and pinch strength was stronger on the arthrodesed side while hand function tests revealed the arthroplasty side to be more dexterous. Subjectively, she preferred the right thumb. Radiographs showed no peritrapezial arthritis in the arthrodesed CMCJ and no proximal migration of the metacarpal on the reconstructed side. Both procedures offered excellent relief of symptoms and she was able to return to work as a machine operator.

Arthritis↗
PubMed1988

Graded effect of protein on regional myoelectric activity of the opossum sphincter of Oddi.

Although it is known that the sphincter of Oddi exhibits a myoelectric response to intraluminal nutrients, the effect of specific dietary components has not been well characterized. The aim of this study was to determine the effect of intragastric instillation of a protein meal on regional myoelectric activity of the opossum sphincter of Oddi. Seven adult opossums were chronically prepared with self-retaining bipolar electrodes secured to the proximal and distal parts of the sphincter. After a 2-week recovery period, and with the animals fasted and conscious, myoelectric activity was recorded for two cycles of the migrating myoelectric complex. The animals then received graded calories of protein through an orogastric tube and recordings were continued until return of the fasted cyclic activity. Doses of 60, 120, and 240 kcal of protein elicited increases in myoelectric spike activity of the proximal sphincter of 18.7%, 41.9%, and 66.6%, respectively. Similarly, the length of the fed state was prolonged by increasing caloric loads, with mean (plus or minus standard error of the mean) times of 266 +/- 25, 292 +/- 15, and 375 +/- 42 minutes for each dose. A similar relationship was noted in the distal part of the sphincter. Regression analysis between the proximal and distal parts of the sphincter during the fasted and fed states showed a strong and persistent correlation of gradient of spikeburst frequency. We conclude that myoelectric spike frequency of the opossum sphincter of Oddi exhibits a dose-related response to intragastric protein calories. Furthermore, the proximal and distal parts of the sphincter remain electrically coupled, with the proximal region pacing the distal region during the fasted state and after protein administration.

Ampulla of Vater↗
PubMedDate not supplied

T gamma cell levels in mammary and cervical uterine cancer patients before and after local irradiation treatment.

Total T and T gamma cell populations were studied in patients suffering from mammary of cervical uterine cancer. The results show that for both groups of patients there were no changes in the total T cell counts when compared with controls: but T gamma subpopulation values were greatly increased in the cancer patient groups, irrespective of in the mammary cancer group, whether the tumor mass was present at the moment of evaluation or surgically removed. The percentage of T mu cells returned to normal level after local irradiation treatment in all cases studied. We speculate about the possible changes in lymphocyte migration as a consequence of irradiation which may affect cells in the blood stream.

Breast Neoplasms↗
PubMed2003

Synovial sheath cell migratory response to flexor tendon injury: an experimental study in rats.

PURPOSE: We aimed to investigate the degree of participation of synovial sheath cells in the process of tendon healing by selective cell labeling and direct observation of migrational pathways. METHODS: We designed a novel rat animal model that employed vital dye staining of synovial sheath cells. The flexor digitorum profundus (FDP) tendon was removed from its sheath and vital dye was applied directly to the synovial sheath cells. A window was cut in the removed tendon before being returned to the sheath, thus placing a tendon injury adjacent to the labeled synovial sheath cells. The synovium remained intact at all times, and labeling was confirmed to be localized to the synovium. The migrational response of the synovial sheath cells to the tendon injury was observed by harvesting the tendons at 1, 3, 5, and 7 days (n = 6 for each time period) after injury and assessing tendon response with frozen sections under ultraviolet microscopy. RESULTS: Labeled synovial sheath cells were observed within the substance of the healing tendon 24 hours after injury, with numbers increasing with time for up to 5 days, but decreasing by day 7. CONCLUSIONS: This study confirms that in the rat model synovial sheath cells move into the healing tendon area and then migrate into the tendon core.

Animals↗
PubMedDate not supplied

Topical diclofenac following excimer laser: effect on corneal sensitivity and wound healing in rabbits.

BACKGROUND: Diclofenac is a nonsteroidal antiinflammatory drug (NSAID) that is widely used systemically and topically. We studied the effect of diclofenac on corneal reepithelialization and corneal sensitivity after excimer laser treatment in rabbits. METHODS: Twelve New Zealand white rabbits were divided into four groups (A, B, C, and D). Groups A and B received diclofenac four times and eight times daily, respectively, following a central 5-millimeter epithelial debridement. Groups C (control) and D (diclofenac four times daily) underwent excimer laser ablation (30-micrometer depth) following manual debridement. Wound healing was compared between groups A and B and groups C and D. Sensitivity was recorded preoperatively and postoperatively 1 to 5 and 14 days in groups C and D until normal values were reestablished. RESULTS: Total time for corneal wound healing and epithelial migration rates was not delayed in any group receiving diclofenac (A, B, and D). Sensitivity after laser ablation reached a minimum of 15% to 20% in both groups C and D by day 2 and returned to normal (100%) by day 8. The decrease in sensitivity between group C, the controls, and group D, receiving diclofenac four times daily, was not statistically significant. CONCLUSIONS: Diclofenac can be used up to eight times daily in the rabbit without causing changes in corneal wound healing or epithelial migration rate. There was no significant, long-term reduction of sensitivity, and recovery was not affected by diclofenac.

Administration, Topical↗
PubMed2002

[Interventional occlusion of interatrial communication after modified Fontan operation].

UNLABELLED: After modified Fontan operations various communications between the systemic and pulmonary venous returns may cause persistent or increasing postoperative cyanosis. Interventional closure of these right-to-left shunts may be necessary to eliminate hypoxemia and to reduce the risk of paradoxical embolic complications. PATIENTS AND METHODS: Eighteen patients with a mean age of 5.6 +/- 4.1 (2.5-17.5) years underwent interventional closure of a right-to-left shunt 17.4 +/- 15.8 (3-60) months after a modified Fontan operation. After test balloon occlusion fenestrations were closed in 13 patients using an Amplatzer Septal occluder (n = 7), a Rashkind PDA occluder (n = 3), a CardioSeal umbrella (n = 1) and detachable coils (n = 2). Residual leaks at the suture lines between the interatrial patch and the right atrial wall were closed using detachable coils and a Rashkind PDA occluder in 2 and 1 patients, respectively. In 3 patients intracardiac venous collateral channels were closed by means of detachable coils. RESULTS: The mean aortic oxygen saturation increased from 85 +/- 4.5 (70-89)% to 91.4 +/- 2.8 (83-95)% (p < 0.001) breathing room air and the mean tunnel pressure rose from 10.7 +/- 1.8 (6-14) mmHg to 12.1 +/- 2.4 (6-16) mmHg (p < 0.001). Calculated Qs decreased from 5.15 +/- 2.1 (2.1-11.3) l/min/m2 to 3.6 +/- 1.0 (1.8-5.6) l/min/m2 (p < 0.001). Mixed venous saturation (66.4 +/- 7.4% vs 65 +/- 7%) and mean systemic arterial pressure (73 +/- 8 mmHg vs 73 +/- 9 mmHg) remained unchanged. In one patient an additional leak of the tunnel could not be closed because of an increase to more than 18 mmHg of the mean pressure in the lateral tunnel during balloon test occlusion. In 2 patients residual leaks after umbrella and coil occlusion of a fenestration and an additional venous collateral channel were closed by means of coils after 16 and 21 months, respectively. At a follow-up of 42 +/- 23 (7-99) months, mean oxygen saturation measured by pulse oxymetry was 93 +/- 2 (90-97)%. In 2 patients color-coded Doppler echocardiography revealed a minimal residual right-to-left shunt. In 2 patients contrast echocardiography demonstrated the additional presence of intrapulmonary fistulas. All patients remained free from device migration, thromboembolic events and hemolysis. CONCLUSION: After modified Fontan operations various right-to-left shunts between the systemic and pulmonary venous returns can be successfully closed using umbrella devices or coils to eliminate cyanosis and to reduce the risk of paradoxical embolism.

Adolescent↗
PubMed1983

[Effect of T-activin on thymocyte reproduction and migration].

Forty seven F1 (CBA X C57Bl) mice were used for quantitative morphologic examination of the thymus on 1, 5, 10 and 15 days after a single injection of 0.5 microgram T-activin, and injections of 0.1 microgram of T-activin once a day during 5 days. The number of transformed thymocytes and mitoses figures in cortex was found to be increased reaching a maximum at the 5th day as regards the magnitude and spreading. By the end of the research the number of transformed thymocytes and mitoses returned to initial values. There was a periodical (at the 5th and 10th days) 1 mm2 reduction in the number of thymocytes, an increase in the proportion of medullary thymocytes, reaching maximum at the 5th day, and a tendency towards the reduction of a relative area of the parenchyma. These indicators did not return to the initial values by the 15th days. However there was a tendency towards normalization. The conclusion is made about the stimulatory effect of T-activin on reproduction and migration of thymocytes.

Animals↗
PubMed1979

Required neural involvement in control of canine migrating motor complex.

This study evaluated the effects of muscarinic, nicotinic, and adrenergic neuronal blockade on the migrating motor complex (MMC) in four unanesthetized dogs. Circular muscle contractile activity was recorded from eight strain gauge force transducers implanted on the stomach and small intestine of each dog. Both atropine sulfate and hexamethonium bromide significantly increased the period of the MMC. When the complex returned after hexamethonium administration, the period of the succeeding complexes was significantly decreased when compared to control. Guanethidine sulfate significantly increased contractile activity on the pylorus, duodenum, and jejunum with a corresponding disruption of the MMC pattern. The migrating motor complex requires the preganglionic release of acteylcholine and possibly an inhibitory input from the sympathetic nervous system for its normal appearance.

Animals↗
PubMed2003

UDP-glucuronosyltransferase-dependent bioactivation of clofibric acid to a DNA-damaging intermediate in mouse hepatocytes.

Glucuronidation of a number of carboxyl-containing drugs generates reactive acyl glucuronide metabolites. These electrophilic species alkylate cell proteins and may be implicated in the pathogenesis of a number of toxic syndromes seen in patients receiving the parent aglycones. Whether acyl glucuronides also attack nuclear DNA is unknown, although the acyl glucuronide formed from clofibric acid was recently found to decrease the transfection efficiency of phage DNA and generate strand breaks in plasmid DNA in vitro. To determine if such a DNA damage occurs within a cellular environment, the comet assay (i.e. single-cell gel electrophoresis) was used to detect DNA lesions in the nuclear genome of isolated mouse hepatocytes cultured with clofibric acid. Overnight exposure to 50 microM and higher concentrations of clofibric acid produced concentration-dependent increases in the comet areas of hepatocyte nuclei, with 1 mM clofibrate producing a 3.6-fold elevation over controls. These effects closely coincided with culture medium concentrations of the glucuronide metabolite formed from clofibric acid, 1-O-beta-clofibryl glucuronide. Consistent with a role for glucuronidation in the DNA damage observed, the glucuronidation inhibitor borneol diminished glucuronide formation from 100 microM clofibrate by 98% and returned comet areas to baseline levels. Collectively, these results suggest that the acyl glucuronide formed from clofibric acid is capable of migrating from its site of formation within the endoplasmic reticulum to generate strand nicks in nuclear DNA.

Animals↗
PubMed1998

Low overall mortality of Turkish residents in Germany persists and extends into a second generation: merely a healthy migrant effect?

OBJECTIVE: To test the hypothesis that as a minority with lower socio-economic status, Turkish residents in Germany might experience a higher mortality than Germans. METHODS: All-cause mortality rates by age group and sex of Turkish and German adults for the time period 1980-94 were calculated from death registry data and mid-year population estimates. RESULTS: The age-adjusted mortality rate (per 100000) of Turkish males aged 25-65 years resident in Germany was 299 in 1980 and 247 in 1990, consistently half that of German males. The mortality of Turkish females in Germany was 140 in 1990, half that of German females. Mortality of Turkish males/females in Ankara was 835 and 426 in 1990. CONCLUSION: In view of the socio-economic status of Turkish residents in Germany the large mortality difference compared to Germans is unexpected. It cannot be fully explained by a selection at the time of hiring (healthy migrant effect) because it lasts over decades and extends into the second generation. A healthy worker effect is unlikely because Turkish residents have a lower employment rate than Germans. There is little evidence for movement of gravely ill persons back to Turkey. An 'unhealthy re-migration effect' in which socially successful migrants with a lower mortality risk stay in the host country while less successful ones return home even before becoming manifestly ill would partly explain our findings.

Adult↗
PubMed1990

A genetic test of the natal homing versus social facilitation models for green turtle migration.

Female green turtles exhibit strong nest-site fidelity as adults, but whether the nesting beach is the natal site is not known. Under the natal homing hypothesis, females return to their natal beach to nest, whereas under the social facilitation model, virgin females follow experienced breeders to nesting beaches and after a "favorable" nesting experience, fix on that site for future nestings. Differences shown in mitochondrial DNA genotype frequency among green turtle colonies in the Caribbean Sea and Atlantic Ocean are consistent with natal homing expectations and indicate that social facilitation to nonnatal sites is rare.

Animals↗
PubMed1992

Hemidesmosomes in the epithelial cell line 804G: their fate during wound closure, mitosis and drug induced reorganization of the cytoskeleton.

Recently, we identified a novel epithelial cell line, 804G, derived from rat bladder, which readily forms hemidesmosomes in vitro. One of the major structural components of the plaques of 804G cell hemidesmosomes is a 230 kDa antigen recognized by autoantibodies in the sera of patients with bullous pemphigoid (BP). An additional polypeptide of 180 kDa also localizes to the hemidesmosome plaque of 804G cells as determined by immunoelectron microscopy. Using confocal fluorescence/phase microscopy, we have employed both 230 kDa and 180 kDa antibody probes to monitor the fate of hemidesmosomes following closure of in vitro wounds, during mitosis, and following drug induced disruption of the cytoskeleton. The punctate cell-substratum associated staining generated by the hemidesmosomal antibodies in stationary unwounded 804G cell cultures is greatly diminished or even lost in cells which enter wound sites, presumably in response to enhanced cell motility. Few, if any hemidesmosomes are observed at the ultrastructural level in cells which have migrated into the wound area. However, as closure of the wound becomes complete, staining along the substratum attached surface of cells returns. During mitosis, there is no obvious loss of hemidesmosomal antigens along the basal surface of 804G cells, and formed hemidesmosomes can be observed in mitotic cells at the ultrastructural level. In 804G cells treated with colchicine, the typical subnuclear pattern of distribution of hemidesmosomal antigens is unaffected. In contrast, following treatment of 804G cells with cytochalasin D, hemidesmosomal antigens become concentrated at the cell periphery and no longer appear in the subnuclear region. Furthermore, formed hemidesmosomes are observed at the cell periphery of cytochalasin D-treated cells by electron microscopy. We suggest that hemidesmosomal plaques are mobile within the plasma membrane. We speculate that hemidesmosomal interactions with extracellular ligands are dynamic and we discuss a possible mechanism by which cytochalasin D induces reorganization of hemidesmosomes along the basal surface of 804G cells.

Actin Cytoskeleton↗
PubMed1989

Thrombocytopenia associated with hypersensitivity to ranitidine: possible cross-reactivity with cimetidine.

A rare case of thrombocytopenia associated with ranitidine is described. The thrombocytopenia was accompanied by eosinophilia and slightly elevated serum IgE. The platelet and eosinophilic counts returned to normal as soon as the drug was stopped. Cell-mediated immunity (CMI) determined in vitro by the leukocyte migration inhibition factor test was found against ranitidine and cimetidine. IgE antibody response against both drugs was also found by the mast cell degranulation test. These data suggest an association between the ranitidine-induced thrombocytopenia and both humoral antibody response and CMI. Cross-reactivity between the two H2-receptor antagonists is suggested, as well.

Cell Migration Inhibition↗
PubMedDate not supplied

[A prognostic assessment of louse-borne typhus (Rickettsia prowazekii infection) in Russia].

From the 1950s to 1974 R.prowazekii infection was registered on the territory of Russia, mainly in the form of Brill's disease, represented by some individual cases in the focus of infection. In 0.25% of all of cases rickettsiosis was linked with group outbreaks of the family character (14 events), reflecting the epidemic form of the disease. From 1974 until the present time the correlation between the sources of infection and the infestation of the population with lice dropped below the critical level, ensuring the transmission of the infective agent among the susceptible human population. This led to the steady disappearance of rickettsiosis (a decrease in the number of rickettsiosis cases from several thousand in the 60s to less than 100 in 1991) due to natural demographic processes. After the disintegration of the USSR, the migration of the population from some regions, especially from those where military conflicts took place, did not affect this process. The return of the epidemic form of rickettsiosis in Russia is impossible.

Disease Outbreaks↗
PubMed1994

Neointima formation after vascular stent implantation. Spatial and chronological distribution of smooth muscle cell proliferation and phenotypic modulation.

Intravascular stents have proved useful as angioplasty devices, but intimal hyperplasia after stent implantation remains an unsolved problem. In the present study, we analyzed the spatial and chronological distribution of proliferation and phenotypes of smooth muscle cells (SMCs) in rabbit aortas during the process of neointima formation after stent implantation (Gianturco's Z type) by immunohistochemistry for proliferating cell nuclear antigen (PCNA) and myosin heavy chain isoforms (SM1, SM2, and SMemb). Stent implantation induced regional injury in the arterial wall. Medial SMCs then began to proliferate adjacent to the injured SMCs, maximally on day 4 (PCNA index in the media: 3.9 +/- 3.4% [mean +/- SD]), and were modulated to the embryonic phenotype (SMemb-positive and SM2-negative). They migrated into the intima and proliferated most frequently on day 7 (PCNA index in the intima: 20.3 +/- 5.5%) and subsequently led to fibrocellular neointima formation at 2 weeks and later. At 1 month after implantation and later, SMC proliferation was rare, and the phenotype of intimal SMCs was gradually returning to the adult type (SMemb-negative and SM2-positive). Thus, this stent implantation model demonstrates that the regional effect on arterial wall by stenting leads to neointima formation through transient and regional proliferation and migration of SMCs and their phenotypic modulations.

Animals↗
PubMed2002

Influence of radial glia and Cajal-Retzius cells in neuronal migration.

Normal development of cerebral cortex depends on proper sequential genesis of cortical neurons and glia. Disruption of corticogenesis in ferret by short-term arresting of cell division using injections of methylazoxy methanol (MAM) leads to a specific constellation of effects, including disruption and early differentiation of radial glia into astrocytes and disorganization of reelin-containing Cajal-Retzius cells. We hypothesize that early interference of normal cortical development removes a factor instrumental in maintaining radial glia in their normal elongated shape. In support of this idea, coculture of MAM-treated slices with normal cortical plate restores radial glia and Cajal-Retzius cells to their normal positions. Recently, we found that conditioned medium obtained from normal organotypic cultures returned radial glia toward their normal morphology only in a fraction of 30-50 kDa molecular weight (MW). To assess whether restoring this factor would also improve effective migration into the cortical plate of E24 MAM-treated animals, we conducted experiments using cocultures of normal cortical plate with organotypic cultures of MAM-treated cortex, which received prior BrdU injections. In both the normal and E24 MAM-treated/normal cortical plate coculture, a greater percentage of BrdU positive cells migrated effectively into the cortical plate. We suggest that early interruption of cell division eliminates a population of cells and a factor important for maintaining proper cortical development, specifically providing cues maintaining elongation of radial glia.

Animals↗