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PubMed1990

Gallbladder and gastrointestinal motility after hemorrhagic shock.

The alterations in fasting gallbladder and gastrointestinal motility during hemorrhagic shock were investigated. Eight opossums implanted with a gallbladder cannula, gastrointestinal bipolar electrodes, and a carotid catheter were subjected to hemorrhagic shock of 30 mm Hg for 60 minutes by the removal of arterial blood. Shed blood was reinfused after the shock period. Fasting gallbladder volume and gastrointestinal electrical activity were studied before, immediately after, and 24 hours after hemorrhagic shock. Control measurements demonstrated a slow-wave frequency maximal in the duodenum (18.1 +/- 1.1 waves/min), with a plateau in the proximal third of the small bowel, decreasing thereafter. The migrating motor complex (MMC) had a duration of 118 +/- 28 minutes. The average volume of the gallbladder before shock was 5.4 +/- 1.5 ml. Gallbladder volume fluctuated with the MMC, being maximal during phase I and minimal in phase III. The volume of blood removed to reduce mean arterial pressure to 30 mm Hg was 45 +/- 5 ml/kg. Immediately after the shock and blood reinfusion, slow-wave frequency decreased by 40% in the antrum and 25% in the small bowel. The MMC was of shorter duration (91 +/- 22 minutes; p less than 0.05), and gallbladder volume increased to 7.0 +/- 1.7 ml (p less than 0.05). Fluctuations in gallbladder volume during the MMC were absent. Twenty-four hours after shock, slow-wave frequency, MMC, and gallbladder volume had returned to normal and were not different from control measurements. Ischemic damage to the gastrointestinal tract is postulated as the cause of gallbladder dysfunction and altered intestinal motility after hemorrhagic shock.

Animals↗
PubMed2006

Neuronal hyperactivity induces astrocytic expression of neurocan in the adult rat hippocampus.

Extracellular matrix molecules are involved in the cellular functions of proliferation, migration, morphological differentiation, and synaptic plasticity. One candidate molecule of the extracellular matrix is the chondroitin sulfate proteoglycan neurocan. To determine whether neurocan expression is regulated by neuronal activity in the adult rat brain, we studied changes in hippocampal neurocan mRNA and protein expression following electrical stimulation of the perforant pathway in urethane-anesthetized rats. After 24 h of intermittent, unilateral 20 Hz stimulation, in situ hybridization revealed increased neurocan mRNA in glial fibrillary acidic protein (GFAP)-positive astrocytes bilaterally in all hippocampal subfields. These changes were quantified in the dentate molecular layer, the termination zone of the perforant pathway, using laser microdissection in combination with quantitative reverse transcription-polymerase chain reaction (RT-PCR). Immediately after 24 h stimulation, a six-fold upregulation was detected, which returned to control levels by 3 days post-stimulation. Neurocan immunoreactivity was similarly upregulated bilaterally. Immunostaining intensity reached a maximum by 4 days and returned to control levels by 14 days. The pattern of neurocan expression in the hippocampus depended on the intensity and duration of electrical stimulation. Under conditions of less intense afferent stimulation (4-24 h of 2.0 Hz paired-pulse stimulation, interpulse interval 40 ms), increases in neurocan mRNA and immunoreactivity were restricted to the ipsilateral termination zone of the stimulated perforant pathway. This layer-specific neurocan upregulation was not affected by intraperitoneal application of the NMDA-receptor antagonist MK-801. In conclusion, our data indicate that synaptic activity regulates the astrocytic expression of neurocan in a graded manner.

Animals↗
PubMedDate not supplied

Neutropenia as a complication of high-dose intravenous immunoglobulin therapy in adult patients with neuroimmunologic disorders.

To investigate clinical aspects of the neutropenia induced by high-dose intravenous immunoglobulin therapy (IVIG) we performed serial hematology, including differentiation of white blood cells (WBC), before and after 22 instances of IVIG in 16 patients with neuroimmunologic disorders. WBC and neutrophils showed a significant decrease with a nadir 2 days after IVIG, but returned to previous values by 14 days with no treatment except in 2 cases. No patient showed any infectious complication. Both WBC and neutrophils were significantly decreased in cases without corticosteroid therapy but not in those with medication. In nine instances (4 with and 5 without corticosteroid treatment), CD11b and CD16 on neutrophils were investigated using flow cytometry. In 3 of 5 instances without corticosteroid treatment the expression of CD11b was decreased after IVIG, while no change was detected in CD16. There was no difference in either CD11b or CD16 between before and after IVIG in instances with corticosteroid therapy. Neutropenia commonly and transiently develops just after IVIG, and can be prevented by corticosteroid pretreatment. Circulating neutrophils might bind to the vascular wall mainly with the involvement of CD11b and migrate into a storage pool, resulting in an apparent neutropenia after IVIG.

Adult↗
PubMed2001

Arthroscopic resection of the distal aspect of the clavicle with concomitant subacromial decompression.

BACKGROUND: Arthroscopic subacromial decompression and arthroscopic resection of the acromioclavicular joint as separate procedures have been well documented. However, there is little information on the success rate of resection with concomitant decompression. In this study, we retrospectively evaluated the results of a consecutive group of patients who underwent arthroscopic resection of the acromioclavicular joint with concomitant subacromial decompression. METHODS: We evaluated the surgical results in thirty-one consecutive patients (thirty-two shoulders) with acromioclavicular pathology with concomitant subacromial impingement. The mean age of the patients at the time of surgery was thirty-six years (range, eighteen to sixty-seven years). Twenty-five patients, including four professional athletes, were actively involved in sports activities. The mean duration of follow-up was four years and ten months (range, three to eight years). The follow-up examination included clinical evaluation, chart review, radiographic analysis, and isokinetic testing of both upper extremities. RESULTS: Of the twenty-five patients who participated in sports, twenty-two (including the four professional athletes) returned to their previous level of sports activity. Twenty-six patients had no pain, three reported mild pain on strenuous repetitive overhead activity, two (both weight-lifters) had occasional pain in the acromioclavicular joint and the lateral aspect of the shoulder with bench-pressing, and two (both baseball players) had mild pain in the posterior aspect of the shoulder with throwing. All of the patients were satisfied with the results. In the absence of a complete rotator cuff tear, isokinetic strength-testing of both upper extremities failed to demonstrate any weakness of the involved shoulder. The mean functional score for individual activities was 2.7 points (range, 2.1 to 3.0 points) preoperatively and 3.9 points (range, 3.6 to 4.0 points) postoperatively (p = 0.0001). No patient had superior migration of the clavicle. The amount of distal clavicular resection averaged 9 mm (range, 7 to 15 mm). One patient had heterotopic ossification at the resection site, with mild pain on direct palpation of the acromioclavicular joint and on strenuous overhead activity. Five patients had calcification at the anterior deltoid insertion into the acromion that was asymptomatic, with no impingement on overhead activity and no pain on direct palpation. CONCLUSIONS: We found excellent results with arthroscopic resection of the acromioclavicular joint and concomitant subacromial decompression. When this procedure is performed on properly selected patients, the results are similar to those of an open approach.

Acromioclavicular Joint↗
PubMed1992

Preservation of continence after ileoanal anastomosis by the coordination of ileal pouch and anal canal motor activity.

Nocturnal incontinence may occur after ileoanal anastomosis and may be related to loss of an effective anal canal pressure barrier during sleep; how pressure and contractions in the proximal bowel influence this barrier is unknown. Our aim was to evaluate the relationship between anal canal pressure and contractions and contractile activity of the pouch in continent subjects after ileal pouch-anal anastomosis (IPAA) and of the rectum in normal controls. A fully ambulatory system for 24-hour pressure recording was used. A flexible transducer catheter was introduced endoscopically so that sensors were at 2, 3, 8, 12, 16, and 24 cm from the anal orifice in 12 healthy controls (7 men, 5 women, mean age: 35 years) and 7 fully continent IPAA patients (4 men, 3 women, mean age: 34 years) more than 12 months postoperatively. Twenty-four hour spontaneous motor activity was stored in a 2.5 megabyte (MB) digital portable recorder. Mean anal canal pressure was calculated, and rectal motor complexes and ileal pouch large pressure waves were characterized. During sleep, resting anal canal pressures were similar in the two groups (72 +/- 12 mm Hg in controls versus 66 +/- 9 mm Hg in IPAA patients [mean +/- standard deviation (SD)], p = NS), but anal canal pressure showed cyclic relaxations (periodicity: 95 +/- 11 min in controls, 54 +/- 18 min in IPAA patients, p less than 0.05), during which the mean pressure trough was 15 +/- 4 mm Hg in controls and 14 +/- 5 mm Hg in IPAA patients (p = NS). In the control patients, during sleep, a mean of six rectal motor complexes were identified (range: 3 to 9). In patients with IPAA, during sleep, a mean of eight large pressure waves per hour were identified (range: 2 to 20). Importantly, in both controls and patients, rectal motor complexes or large pressure waves were always accompanied by rapid return of anal canal pressure from trough to basal values and increased contractile activity. We concluded that, in healthy patients and in continent patients after IPAA, motor activity of the rectum and of the ileal pouch was associated with changes in pressure and contractile activity of the anal canal so that rectal- and neorectal-anal canal pressure gradient, and, in turn, fecal continence were preserved.

Adult↗
PubMed1995

Lymphocytes migrate from the bronchoalveolar space to regional bronchial lymph nodes.

The fate of lymphocytes in the bronchoalveolar tract was studied in normal young pigs. Peripheral blood lymphocytes were labeled with 51chromium or with fluorescein isothiocyanate (FITC) and instilled into a single segmental bronchus. In the first series of experiments, the radioactivity was determined in several different parts of the lungs, individual bronchial lymph nodes and a series of other lymphoid and nonlymphoid organs. About two-thirds of the radioactivity was still in the lung at 1 d. The draining lymph node also contained high amounts of radioactivity. To exclude that this was caused by labeled cell debris, an immunohistologic technique was used to localize the FITC-labeled cells. There were clearly labeled lymphocytes in the sinusoids of the draining nodes. These lymphocytes were characterized by additional surface staining. B, T, TH, and TS lymphocytes were seen much less often than in the inoculum while the null and gamma delta T cells showed a preference. The lymphocytes reached the bronchial lymph nodes via lymphatics. Lymphocytes in the bronchoalveolar space are not effete cells to be destroyed but return to the immune system. These data provide new interest in the immunologic role of lymphocytes in the bronchoalveolar tract and their kinetics.

Animals↗
PubMed2000

Profiles of refugee and non-refugee Palestinians from the West Bank and Gaza.

Relying on demographic and labor surveys which the Palestinian Central Bureau of Statistics collected in 1995, this article investigates the profile of West Bank and Gaza refugees. Refugees are better educated and have higher fertility than non-refugee Palestinians, but the difference is small. However, they have a significantly lower participation rate, a higher unemployment rate and a higher incidence of arrests and work stoppage than the corresponding rates among non-refugee Palestinians. A smaller proportion of Palestinians commute to work into the Israeli labor market and refugees earn lower wages than nonrefugees. Returns to investment in education are small for both groups. High fertility among refugees imposes a future challenge for policy makers in terms of resources required for the provision of appropriate education and health facilities. Employing future labor market entrants is another serious policy challenge.

Asia↗
PubMed1989

Molecular forms of serum insulin-like growth factor (IGF)-binding proteins in man: relationships with growth hormone and IGFs and physiological significance.

Insulin-like growth factor-I (IGF-I) and IGF-II are associated in the blood with specific binding proteins (BPs), forming complexes that elute in gel filtration with estimated mol wt around 40 and 150 kD. The latter appears to be under GH control. Five molecular forms of BP (41.5, 38.5, 34, 30, and 24 kD) have been identified by Western blotting using 125I-labeled IGF. All five forms are present in the smaller complexes, but only the 41.5- and 38.5-kD forms are found in the larger complexes. In this study immunoblotting showed that the 41.5- and 38.5-kD forms were recognized by antibodies directed against the GH-dependent BP purified from human plasma, and the 30-kD form was recognized by antibodies directed against the BP purified from amniotic fluid. The 34- and 24-kD forms proved to be immunologically unrelated to the other three. In sera with large quantities of the 41.5- and 38.5-kD forms, an additional band was often observed immediately ahead of the migration front of the 30 kD band. This was recognized by the anti-GH-dependent BP antibody and probably corresponds to a degradation product of the 41.5- and 38.5-kD BPs. Serum 41.5- and 38.5-kD BPs have been found to be elevated in acromegaly, where GH hypersecretion causes increased IGF-I levels, and diminished in cases of genetic or idiopathic GH deficiency and defects of the GH receptor (Laron's syndrome), where both IGF-I and IGF-II are decreased, as well as in Pygmy adults and children who have isolated IGF-I deficiency. In all of these conditions, the proportions of the 34- and 30-kD forms were inversely related to those of the 41.5- and 38.5-forms. Under treatment, the BP profiles tended to return to normal. In cases of GH deficiency caused by a tumor, the BP profiles resembled those of hypopituitary or normal serum, depending on whether IGF levels were diminished or normal. It, therefore, seems that BP synthesis is coordinated with IGF-I synthesis and may not be directly GH dependent. The results of neutral pH gel filtration analysis of hypopituitary (idiopathic and tumoral) and normal sera point to a relationship between the levels of circulating IGFs and those of the 150-kD IGF-BP complex whose binding units are the 41.5- and 38.5-kD BPs. It, therefore, seems that the 150-kD complex controls the bioavailability of IGF-I and IGF-II.(ABSTRACT TRUNCATED AT 400 WORDS)

Acromegaly↗
PubMed2003

Year-to-year differences in plasma levels of steroid hormones in pre-spawning chum salmon.

Changes in plasma levels of steroid hormones in pre-spawning chum salmon (Oncorhynchus keta) were examined for 6 years in association with sexual maturation. Fish were sampled along their homing pathway from the coastal sea to the spawning ground from 1995 to 2000. Plasma levels of testosterone (T), 11-ketotestosterone (11KT), estradiol-17beta (E2), 17alpha,20beta-dihydroxy-4-pregnen-3-one (DHP), and cortisol were determined by enzyme immunoassays. Sexual maturity was comprehensively estimated by gonadosomatic indices, histology of gonads, nuptial color, spermiation or ovulation ratio. Since the plasma levels of steroid hormones and sexual maturation differed from year to year, they were compared with year-to-year variation of sea surface temperature (SST) of coastal sea to study influence of oceanographic environment on these physiological data. The SST of the migratory route varied among the years, so that we classified the 6 years into cool, intermediate, and warm years. Concerning maturity, the males that returned to the natal hatchery in the warm years were sexually more advanced than those in the cool years. Furthermore, histological data suggested that final oocyte maturation occurred before arrival at the hatchery in one of the warm years, i.e., 1999, while it occurred at the hatchery in one of the intermediate years, i.e., 2000. In the males, T and 11KT levels increased significantly on midway of the homing route in the warm years, whereas they did not show any noticeable changes in the cool years. Furthermore, the levels of T and 11KT on midway of the homing route in the warm years, i.e., 1998 and 1999, were significantly higher than those in one of the cool years, i.e., 1995, in both sexes. In the females, the levels of E2 decreased during upstream migration. Conversely, those of DHP considerably elevated at spawning ground in all years examined. The levels of cortisol were different from year to year regardless of the SST. The present results showed that there were year-to-year differences in plasma levels of steroid hormones and maturity, and some of them may be influenced by the year-to-year variation of SST.

Animals↗
PubMed1995

Induced expression of adhesion molecules following focal brain ischemia.

Central nervous system injuries such as focal brain ischemia and trauma are known to initiate inflammatory reactions. To demonstrate the involvement of adhesion molecules in these inflammatory responses, we have observed significant increases of ICAM-1 and ELAM-1 mRNA expression in the ischemic cortex of rats by means of Northern blot analysis and/or semiquantitative reverse transcription and polymerase chain reaction (RT-PCR). In the ischemic cortex, levels of ICAM-1 mRNA increased significantly at 3 h (2.6-fold, p < 0.05), peaked at 6 to 12 h (6.0-fold, p < 0.01), and remained elevated for up to 5 days (2.5-fold, p < 0.05) after permanent occlusion of the middle cerebral artery (PMCAO). The basal expression of ELAM-1 mRNA was extremely low (undetectable by Northern analysis). Following focal ischemia, however, ELAM-1 mRNA was markedly increased at 6 h in the ischemic cortex, peaked at 12 h (6.4-fold increase compared to sham samples, p < 0.01), and then returned to almost basal levels by 5 days post-PMCAO. Immunohistochemical stainings using anti-ICAM-1 antibodies demonstrated a marked increase of ICAM-1 in the ischemic cortex over the nonischemic cortex or the sham-operated samples. The immunoreactive ICAM-1 signal was localized to endothelial cells of intraparenchymal blood vessels in the ischemic cortex. Furthermore, time-course analysis demonstrated that the increased expression of ICAM-1 and ELAM-1 parallel those of chemokines such as KC and MCP-1, but are more delayed than those of inflammatory cytokines including TNF-alpha and IL-1 beta, which are known to induce expression of ICAM-1 and ELAM-1 on endothelial cells. The upregulation of the inflammatory genes and their products precedes leukocytes' adhesion to endothelial cells and their migration into the ischemic tissue, suggesting that these upregulated adhesion molecules on brain capillary endothelium play an important role in leukocyte migration into ischemic brain tissue.

Animals↗
PubMed1998

Effect of local injection of botulinum toxin on sphincter of Oddi cyclic motility in dogs.

To study effects of intrasphincteric injections of botulinum toxin on the sphincter of Oddi cyclic motility and responses to motilin and cholecystokinin, four conscious dogs with duodenal cannula underwent manometry of the common bile duct, sphincter of Oddi, and duodenum. After baseline recording, each dog had intrasphincteric injections of saline or botulinum toxin. The injections of saline had no effect, whereas botulinum toxin significantly reduced mean basal pressure, amplitude, and motility index of the sphincter of Oddi. These effects took place in four to seven days and reached a maximum in seven to 10 days. The basal pressure returned to the baseline level in 28 weeks, but the amplitude and motility index remained low. The pressure parameters of motilin-induced premature phase III-like activity also decreased, but action of cholecystokinin was not affected. These results indicate that the botulinum toxin injections reduce sphincter of Oddi phasic contractile activity for a prolonged period of time.

Animals↗
PubMed1999

Management of a rare complication of endovascular treatment of direct carotid cavernous fistula.

A 30-year-old woman with direct carotid cavernous fistula underwent endovascular treatment with detachable balloons via a transarterial route. The patient returned with diplopia 1 year after therapy. On cranial MR imaging, one of the balloons was detected in the proximal portion of the superior ophthalmic vein and was deflated percutaneously with a 22-gauge Chiba needle under CT guidance. The patient's symptoms resolved after balloon deflation. This case report presents a unique complication of endovascular treatment of direct carotid cavernous fistula and its management.

Adult↗
PubMed2001

Effect of gravity on the interaction between the avian germ and neighbouring ooplasm in inverted egg yolk balls.

The developmental capacities of an avian germ (from before symmetrization to the moment of laying) are strongly diminished after inversion of its egg yolk ball followed by culture in egg white. Our present experiments show that even when the avian germ is completely horizontally inverted (without an upper or lower border) below its egg yolk ball before symmetrization, symmetrization and gastrulation phenomena take place. The germ grows slower and becomes smaller than after normal incubation. After culture of inverted unincubated germs, localized on freshly laid eggs, the closure of the neural tube is impaired and it remains open over a long distance. Although a primitive streak (PS) develops, mesoderm migration (mainly from the lateral part of the area pellucida) is also impaired. On sections through the germinal disc one can see the abnormal upward migration into the depth of the ooplasm and yolk of cells from the germ wall and the development of large cellular extensions encircling the yolk globules. Most prominent is the loss of contact between the superficial cell layers and the deep layer elements (junctional endoblast and yolk endoblast in the area opaca). Large areas without deep layer elements (even visible on surface micrographs) develop in the area vasculosa and area vitellina interna. The margin of overgrowth grows and extends normally over the egg yolk ball. An autoradiographic study after labelling of the yolk layers in inverted egg yolks reveals that mainly compression of the peripheral subgerminal and perigerminal ooplasm takes place. This suggests that the compression by the neighbouring yolk and upwards growth of cells are at the origin of the impaired development. After return to the normal upward orientation of the germ on the topmost part of the egg yolk ball, a more or less pronounced restoration to normal development takes place (depending on the duration of the inversion period and the age of the germ).

Animals↗
PubMed2001

alpha4 integrin in islet allograft rejection.

BACKGROUND: Adhesion molecules are involved in multiple steps of the continuum of allograft rejection. We studied the effects of blockade of the interactions between alpha4 integrin and its ligands, vascular cell adhesion molecule-1 (VCAM-1) and fibronectin, on allograft survival. METHODS: Streptozotocin-induced diabetic CBA (H-2k) mice received islet transplants from BALB/c (H-2d) donors. Recipient mice were treated with antibodies against alpha4 integrin (PS/2), VCAM-1 (MK 2.7), and a peptide corresponding to the binding site of alpha4 integrin on fibronectin (connecting segment 1 peptide, CS1-peptide). Graft function was measured by daily tail vein blood glucose levels, with rejection defined as the return of hyperglycemia. Graft-bearing kidneys were removed for immunohistochemical analysis. RESULTS: Treatment with anti-alpha4 integrin antibody, anti-VCAM-1 antibody, or with CS1-peptide led to long-term survival of islet allografts. Recipients with long-surviving islet grafts did not show tolerance, in that they rejected a second donor-type islet allograft. Although both anti-alpha4 integrin antibody and CS1-peptide completely abolished cellular infiltration of the islet graft 7 days after transplantation, anti-VCAM-1-treated recipients showed a dense peri-islet infiltrate of activated, alpha4 integrin+, cytotoxic T cells. CONCLUSIONS: These data show that alpha4 integrin is critically important to allograft rejection. Anti-VCAM-1 antibody appears to prevent rejection without qualitatively affecting either T cell activation or migration to the graft. Conversely, anti-alpha4 integrin antibody and CS1-peptide may prevent islet allograft rejection by altering either T cell activation or lymphocyte trafficking. Blocking interactions between alpha4 integrin and its ligands may provide novel forms of immunosuppression.

Animals↗
PubMed1982

T-cell recirculation in the sheep: migratory properties of cells from lymph nodes.

T lymphocytes derived from different sources in sheep were compared for their ability to recirculate from blood to lymph. Nylon wool columns were used to prepare T-cell-enriched populations from efferent intestinal lymph, efferent prescapular lymph and from cell suspensions of mesenteric lymph nodes and prescapular lymph nodes. With each animal, T cells from two of the above sources were labelled in vitro, one population with fluorescein isothiocyanate the other with rhodamine isothiocyanate; both populations were returned to the animal at the same time by intravenous injection. The intestinal lymph and prescapular lymph were continuously monitored to compare the recirculating properties of the two populations of T cells. This technique led to confirmation of the earlier reports in sheep of a preferential recovery of intestinal lymph T cells and of prescapular lymph T cells in the lymph from which the cells were originally collected. This phenomenon was much less evident with T cells from mesenteric nodes and prescapular nodes and in a number of experiments a random pattern of recirculation occurred. It is concluded that there are differences in the composition of the T-cell population in a node compared with that of the lymph draining the node. The advantages of using fluorescently-labelled cells to study lymphocyte migration are discussed.

Animals↗
PubMed2002

In allergic asthma experimental exposure to allergens is associated with depletion of blood eosinophils overexpressing LFA-1.

BACKGROUND: In atopic individuals, exposure to allergens is followed by recruitment of blood eosinophils in the target tissue. We investigated whether allergen inhalation challenge could result in depletion of blood eosinophils overexpressing adhesion molecules involved in eosinophil migration. METHODS: Blood eosinophils were isolated from seven atopic asthmatic patients and seven control subjects and the "at baseline" expression of lymphocyte function-associated antigen-1 (LFA-1), macrophage antigen-1 (Mac-1) and very late antigen-4 (VLA-4) was assessed by monoclonal antibody staining and flow cytometry analysis. Asthmatic patients underwent allergen challenge and the expression of LFA-1, Mac-1 and VLA-4 by blood eosinophils was again evaluated 3 h and 24 h after allergen challenge. RESULTS: As compared to controls, eosinophils from atopics showed at baseline enhanced LFA-1 expression (P=0.0012), but similar Mac-1 or VLA-4 expression (P > 0.1, each comparison). In atopics, the percentage and absolute number of blood eosinophils were significantly decreased 3 h after allergen challenge (P=0.001 and P=0.022, respectively) but returned to similar values to prechallenge values after an additional 21 h (P > 0.1). Allergen challenge was also followed by a significant decrease in LFA-1 expression by eosinophils, at 3 h (P=0.002) and at 24 h (P=0.038), while no changes in Mac-1 and VLA-4 were observed. A significant correlation between postchallenge decrease in LFA-1 expression and in blood eosinophilia, both expressed as percentage (r=0.88; P < 0.01) or absolute number (r=0.87; P < 0.01) was demonstrated at 3 h (r=0.88; P < 0.01) but not at 24 h (r=0.64, P > 0.05 and r=0.11; P > 0.05, respectively). CONCLUSION: In allergic asthma, an early recruitment of blood eosinophils overexpressing LFA-1 occurs in the first hours after allergen challenge.

Adolescent↗
PubMed2003

Mitigation of neutrophil infiltration in a rat model of early Staphylococcus aureus endophthalmitis.

PURPOSE: Infectious endophthalmitis is characterized by neutrophil migration into the eye. The purpose of this study was to determine whether systemic neutrophil depletion mitigates the ocular influx of neutrophils during the early phases of experimental endophthalmitis. METHODS: Endophthalmitis was induced in rats by intravitreal injection of Staphylococcus aureus. Animals received a single systemic dose of an anti-neutrophil-depleting antibody (dAb) or normal rabbit serum (NRS) 6 or 12 hours after intravitreal injection. Inflammation was graded both in vivo and by histopathology. Myeloperoxidase (MPO) was used as a biomarker of neutrophil infiltration. Bacterial clearance was evaluated by determining the amount of viable bacteria recovered from ocular specimens. RESULTS: Rats that received dAb 6 hours after bacterial injection exhibited significantly lower clinical scores, MPO activity, fewer vitreous exudates, and higher vitreous bacterial counts at 24 hours (P < 0.05). As the neutrophil population returned in this group, measured by the number in the peripheral blood, increasing intraocular inflammation was observed. Rats receiving dAb 12 hours after vitreous injection also demonstrated significantly lower clinical scores, MPO activity and less vitreous exudates at the 24-hour time point (P < 0.05). No significant differences from the control were detected at any of the subsequent time points, except in bacterial counts and MPO activity. CONCLUSIONS: Depletion of neutrophils early in the inflammatory response delayed the onset of severe ocular inflammation but also prevented adequate bacterial clearance. These results confirm the important role of neutrophils in ocular host defense during the early stages of experimental endophthalmitis.

Animals↗
PubMed1995

The kinetics of murine hematopoietic stem cells in vivo in response to prolonged increased mature blood cell production induced by granulocyte colony-stimulating factor.

Because of the complexity of appropriate stem cell assays, little information on the in vivo regulation of murine stem cell biology or stemmatopoiesis is available. It is unknown whether and how in vivo the primitive hematopoietic stem cell compartment is affected during a continued increased production of mature blood cells. In this study, we present data showing that prolonged (3 weeks) administration of granulocyte colony-stimulating factor (G-CSF), which is a major regulator of mature granulocyte production, has a substantial impact on both the size and the location of various stem cell subset pools in mice. We have used the novel cobblestone area forming cell (CAFC) assay to assess the effects of G-CSF on the stem cell compartment (CAFC days 7, 14, 21, and 28). In marrow, in which normally 99% of the total number of stem cells can be found, G-CSF induced a severe depletion of particularly the most primitive stem cells to 5% to 10% of normal values. The response after 7 days of G-CSF treatment was an increased amplification between CAFC day 14 and 7. However, this response occurred at the expense of the number of CAFC day 14. It is likely that the resulting gap of CAFC day 14 cell numbers was subsequently replenished from the more primitive CAFC day 21 and 28 compartments, because these cell numbers remained low during the entire treatment period. In the spleen, the number of stem cells increased, likely caused by a migration from the marrow via the blood, leading to an accumulation in the spleen. The increased number of stem cells in the spleen overcompensated for the loss in the marrow. When total body (marrow and spleen) stem cell numbers were calculated, it appeared that a continued increased production of mature granulocytes resulted in the establishment of a higher, new steady state of the stem cell compartment; most committed stem cells (CAFC day 7) were increased threefold, CAFC day 14 were increased 2.3-fold, CAFC-day 21 were increased 1.8-fold, and the most primitive stem cells evaluated, CAFC day 28, were not different from normal, although now 95% of these cells were located in the spleen. Four weeks after discontinuation of the G-CSF treatment, the stem cell reserve in the spleen had returned to a normal level, whereas stem cell numbers in marrow had recovered to values above normal. This study shows that the primitive stem cell compartment is seriously perturbed during an increased stimulation of the production of mature blood cells.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗