Factor XI contributes to thrombus propagation on injured neointima of the rabbit iliac artery.

BACKGROUND: Thrombus formation through the activation of tissue factor (TF) and factor (F) XI is a critical event in the onset of cardiovascular disease. TF expressed in atherosclerotic plaques and circulating blood is an important determinant of thrombogenicity that contributes to fibrin-rich thrombus formation after plaque disruption. However, the contribution of FXI to thrombus formation on disrupted plaques remains unclear. METHODS: A mouse monoclonal antibody against FXI and activated FXI (FXIa) (XI-5108) was generated by immunization with activated human FXI. Prothrombin time (PT), activated partial thromboplastin time (APTT), bleeding time, and ex vivo platelet aggregation in rabbits were measured before and after an intravenous bolus injection of XI-5108. We investigated the role of FXI upon arterial thrombus growth in the rabbit iliac artery in the presence of repeated balloon injury. RESULTS: The XI-5108 antibody reacted to the light chain of human and rabbit FXI/FXIa, and inhibited FXIa-initiated FXa and FXIa generation. Fibrin-rich thrombi developed on the injured neointima that was obviously immunopositive for glycoprotein IIb-IIIa, fibrin, TF, and FXI. Intravenous administration of XI-5108 (3.0 mg kg(-1)) remarkably reduced thrombus growth, and the APTT was significantly prolonged. However, PT, bleeding time and platelet aggregation were not affected. CONCLUSIONS: These results indicate that plasma FXI plays a potent role in thrombus growth on the injured neointima. Inhibition of plasma FXI activity might help to reduce thrombus growth on ruptured plaques without prolonging bleeding time.

Effect of 8-methoxypsoralen plus UVA on psoriasis leukotactic factor.

The effect of psoralen phototherapy on the chemotactic activity of psoriasis leukotactic factor (PLF) was studied. The chemotactic activity of PLF extracted from psoriasis scales was evaluated using modified Boyden chambers. Treatment of (1) psoriasis lesions, (2) psoriasis scale and (3) extracted PLF with 8-methoxypsoralen plus UVA irradiation reduced the chemotactic activity of PLF. These results may help define the mechanism of psoralen phototherapy in psoriasis.

Iridolenticular contact decreases following laser iridotomy for pigment dispersion syndrome.

OBJECTIVE: To evaluate changes in anterior segment anatomy after laser iridotomy for pigment dispersion syndrome. METHODS: Ultrasound biomicroscopy was performed on 7 eyes of 7 untreated patients with reverse pupillary block and pigment dispersion syndrome. A radially oriented image with the probe perpendicular to the eye in the superior meridian was obtained before and at least 1 week after laser iridotomy in each eye. We assessed changes in angle recess area and iris-lens contact distance. RESULTS: Mean +/- SD patient age was 31.3 +/- 5.7 years and mean +/- SD refractive error was -5.0 +/- 3.9 diopters. Angle recess area (mean +/- SD, 0.78 +/- 0.28 vs 0.35 +/- 0.11 mm2; P=.001, paired t test) and iris-lens contact distance (2.05 +/- 0.28 vs 0.79 +/- 0.13 mm; P<.001) decreased following iridotomy. Central anterior chamber depth did not change. CONCLUSION: Flattening of the iris following laser iridotomy for pigment dispersion syndrome causes a decrease in iris-lens contact and angle width while lens position remains constant.

Iris and ciliary body melanomas: ultrasound biomicroscopy with histopathologic correlation.

OBJECTIVE: To correlate ultrasound biomicroscopic images of iris and ciliary body melanomas with their histopathologic features. METHODS: Ultrasound biomicroscopy was performed in 3 cases of iris melanoma and in 3 cases of ciliary body melanoma. Cross-sectional ultrasound biomicroscopic images were compared with findings from clinical examination and light microscopy to evaluate associations between their histopathologic, surface, and internal ultrasound characteristics. Unique images of intrastomal and obscured posterior tumor margins were visualized by ultrasound biomicroscopy. RESULTS: Results of this study revealed that ultrasound biomicroscopy offers an accurate method to evaluate tumor shape, reflectivity, and local invasion. Neoplastic tissue had only medium echogenicity. Enlarged vessels were correlated to echolucent spaces in the iris stroma. Anterior tumor margins were found within the iris stroma, within the anterior chamber angle, and on the endothelial surface of the cornea. Posterior tumor extension was noted to encroach onto the lens, into the sclera, and serous peripheral retinal detachments were associated with ciliary body tumors. CONCLUSION: Ultrasound biomicroscopic images correlated well with histopathologic features of anterior uveal melanomas including shape, reflectivity, and local extension. Arch Ophthalmol. 2000;118:1515-1521

Anterior segment implantation cysts. Ultrasound biomicroscopy with histopathologic correlation.

OBJECTIVE: To correlate the clinical, histopathologic, and ultrasound biomicroscopic characteristics of anterior segment implantation cysts. METHODS: We performed a retrospective review of 7 cases of secondary anterior segment implantation cysts. We reviewed the clinical history, visual acuity, clinical findings, and ultrasound biomicroscopic characteristics in all cases. Histopathologic correlation was possible in 4 cases. RESULTS: Six eyes had been subjected to major trauma prior to cyst formation. Trauma was noted as blunt in 3 eyes and surgical in 3 eyes. The diagnosis was confirmed in 1 eye when conjunctival cells were aspirated on fine needle biopsy. Ultrasound biomicroscopy revealed large (mean +/- SD greatest diameter, 4.7 +/- 0.9 mm) cystic tumors. In 1 patient, a cyst-related indentation of the anterior lens surface was seen. Ultrasonographic evaluations of internal reflectivity revealed thick, moderately reflective cyst walls encapsulating a relatively hypoechoic core. In 3 cases, the cyst contents consisted of variably reflective material. The other 4 were completely sonolucent. Histopathologic correlation showed that the cyst walls were lined with stratified squamous epithelium. The moderately reflective cyst contents were found to be degenerated conjunctival cells with inflammatory foci and cholesterol crystals. The sonolucent regions correlated with inflammatory cells and fluid. CONCLUSIONS: This study demonstrates that implantation cysts are unilateral, large, and thick walled. They may be sonolucent or exhibit variable internal reflectivity. These findings as well as the extent of anterior segment involvement (particularly posterior extension) could be evaluated by ultrasound biomicroscopy prior to surgery.

Polypeptide and carbohydrate structure of recombinant human interleukin-6 produced in Chinese hamster ovary cells.

A glycosylated form of human interleukin 6 (hIL-6) has been produced in Chinese hamster ovary (CHO) cells transfected with a cDNA clone for human IL-6. Recombinant hIL-6 was purified from a culture supernatant of the transfected CHO cells, and used for structural characterization. The complete amino acid sequence, composed of 185 amino acid residues, was determined and is identical to that predicted from the cDNA sequence. However, a recombinant hIL-6 species lacking two amino acid residues (Ala-Pro) from the N-terminus was also found. Two disulfide bonds are formed, between Cys45 and Cys51 and between Cys74 and Cys84. Recombinant hIL-6 carries one O-linked carbohydrate chain, and Thr139 is fully O-glycosylated. A portion of recombinant hIL-6 protein carries one N-linked sialooligosaccharide chain, and the N-glycosylation occurs at Asn46. The structure of the N-linked sugar chains was estimated by a combination of sugar mapping and glycosidase digestion. The major structure of the N-linked sugar chain predicted was of a fucosylated biantennary or triantennary complex type. Fucosylated triantennary sugar chains with one or two N-acetyllactosaminyl repeats were also found. The structure of the O-linked sugar chain was determined by 500 mHz 1H-NMR to be NeuAc alpha 2-3Gal beta 1-3(NeuAc alpha 2-6) Gal-NAcol.

Reduced blood flow in abdominal viscera measured by Doppler ultrasound during one-legged knee extension.

The redistribution of blood flow (BF) in the abdominal viscera during right-legged knee extension-flexion exercise at very low intensity [peak heart rate (HR), 76 beats/min] was examined by using Doppler ultrasound. While sitting, subjects performed a right-legged knee extension-flexion exercise every 6 s for 20 min. BF was measured in the upper abdominal aorta (Ao), right common femoral artery (RCFA), and left common femoral artery (LCFA). Visceral BF (BFVis) was determined by the equation [BFAo - (BFRCFA + BFLCFA)]. A comparison with the change in BF (DeltaBF) preexercise showed a greater increase in DeltaBFRCFA than in DeltaBFAo during exercise. This resulted in a reduction of BFVis to 56% of its preexercise value or a decrease in flow by 1,147 +/- 293 (+/-SE) ml/min at the peak workload. Oxygen consumption correlated positively with DeltaBFAo, DeltaBFRCFA, and DeltaBFLCFA but inversely with DeltaBFVis during exercise and recovery. Furthermore, BFVis (% of preexercise value) correlated inversely with both an increase in HR (r = -0.89), and percent peak oxygen consumption (r = -0.99). This study demonstrated that, even during very-low-intensity exercise (HR <90 beats/min), there was a significant shift in BF from the viscera to the exercising muscles.

Effects of epinephrine and lactate on the increase in oxygen consumption of nonexercising skeletal muscle after aerobic exercise.

The purpose of this study was to measure O2 consumption of nonexercising skeletal muscles (VO2nonex) at rest and after aerobic exercise and to investigate the stimulant factors of O2 consumption. In experiment 1, we measured the resting metabolic rate of the finger flexor muscles in seven healthy males by 31P-magnetic resonance spectroscopy during a 15 min arterial occlusion. In experiment 2, the VO2nonex of the finger flexor muscles was measured using near infrared continuous wave spectroscopy at rest, immediate postexercise, and 3, 5, 10, 15, and 20 min following a cycling exercise at a workload corresponding to 50% of peak pulmonary O2 uptake for 20 min. We also monitored deep tissue temperature in the VO2nonex measurement area and determined catecholamines and lactate concentrations in the blood at rest and immediate postexercise. VO2nonex at rest was 1.1 +/- 0.1 microM O2/S (mean +/- standard error) and VO2nonex after exercise increased 59.6 +/- 7.2% (p < 0.001) from the resting values. There were significant correlations between the increase in VO2nonex and the increase in epinephrine concentration (p < 0.01), and between the increase in VO2nonex and the increase in lactate concentration (p < 0.05). These results suggest that epinephrine and lactate concentrations are important VO2nonex stimulant factors.

Muscle fiber growth and necrosis in dystrophic muscles: a comparative study between dy and mdx mice.

Histopathological and morphometric studies of murine dystrophic muscles in the early postnatal period were performed. In dy mice, obtained by in vitro fertilization, scattered necrotic fibers were noted at 10 days of age followed by poorly compensated regeneration leading to muscle fiber loss, marked variation in fiber size, and fibrous and adipose tissue proliferation. In mdx mice, clusters of necrotic muscle fibers seen at 10-15 days were followed by well compensated regeneration with little fibrosis. There appeared to be no delay in muscle fiber growth and fiber type differentiation in both dy and mdx mice up to 10 days of age since there was no distinct difference in muscle fiber size, fiber type differentiation and the incidence of myosatellite cells between dystrophic muscles and those from age-matched control mice. Muscle fibers appeared to undergo necrosis only when they had reached a certain stage of maturation since at early stages of development or regeneration they rarely became necrotic. The difference in clinical symptoms between dy and mdx mice may result from differences in their regenerative response to necrosis.

Effect of psoralen + ultraviolet-A on the chemotactic activity of polymorphonuclear neutrophils towards anaphylatoxin C5a des Arg.

It was shown that psoralen + UV-A inhibits the chemotactic activity of polymorphonuclear neutrophils towards anaphylatoxin C5a des Arg. This reaction required oxygen and there is a high possibility that the active oxygen species was in a singlet state. Oxygen did not act directly on C5a des Arg, but rather produced oxidized psoralen which inhibited C5a des Arg activity. The effect was dependent on the concentration and types of psoralen and on the UV-A dose. Among the psoralens, the inhibitory effect of 4,5',8-trimethylpsoralen was the strongest, followed by 8-methoxypsoralen and 3-carbethoxypsoralen and finally 4,4',6-trimethylangelicin. Psoralen + UV-A failed to inhibit the chemotactic activity towards chemotactants other than anaphylatoxin C5a such as casein, the cultured filtrate of E. coli, platelet-activating factor, leukotriene B4, 5-hydroxy-6,8,11,14-eicosatetraenoic acid and 12-L-hydroxy-5,8,10,14-eicosatetraenoic acid.

Structural elucidation of the 8-methoxypsoralen oxidized product that inhibits the chemotactic activity of polymorphonuclear neutrophils toward anaphylatoxin C5a.

The chemical structure of the 8-methoxypsoralen oxidized product that inhibits the chemotactic activity of anaphylatoxin C5a was determined to be 2,3-dihydro-2,9-dimethoxy-3-hydroxy-7-oxo-7H-furo[3,2-g] [1]benzopyran. Its minimal concentration required to obtain the maximum inhibition of C5a des Arg (1 x 10(-8) M) chemotactic activity is 2.5 x 10(-8) M. Bioactivity of this substance was maintained for 2 weeks, stored in a dark room at room temperature under aerobic conditions. There is a possibility that this substance may be useful in the treatment of immune complex diseases.

Genetic control of the radiosensitivity of lymphoid cells for antibody formation ability in mice.

To analyze the genetic basis of the relationship between the radiosensitivity of the immune response and radiation lymphomagenesis, we examined the radiosensitivity of lymphoid cells for antibody formation in BALB/cHeA, STS/A, F1 hybrids, and their recombinant inbred mouse strains. The decrease in the number of plaque-forming spleen cells in BALB/cHeA mice exposed to 3 Gy X-irradiation was more than tenfold that in STS/A mice. The phenotype of radioresistance was dominant over sensitivity. The coincidence between the strain distribution patterns of the genetic markers and radiosensitivities of antibody formation in the various recombinant inbred strains was in the region with the Igh locus on chromosome 12. There was obvious difference between the patterns in the region containing the Ifa locus on chromosome 4 which has been shown to be related to the incidence of radiation-induced lymphomas. These results indicate that the region on chromosome 12 may contain major gene(s) related to radiosensitivity for antibody formation.

Factors related to resistance to hematopoietic death in mice.

Mouse strain difference in the radiosensitivity to hematopoietic death is thought to be determined by several factors besides radiosensitivity and the initial number of hematopoietic stem cells. Factors related to the survival of mice exposed to X-irradiation were analyzed using BALB/cHeA and STS/A strains whose LD50/30 values differ markedly (BALB/cHeA, 5.55 Gy; STS/A, 8.45 Gy). STS/A mice exposed to 4 Gy of X-irradiation showed a small reduction but rapid recovery of blood cells (leukocytes, erythrocytes, and thrombocytes) when compared with BALB/cHeA mice. The survival of endogenous and exogenous CFU-S was much higher, by a magnitude of one log or more, in STS/A mice than those in BALB/cHeA mice; whereas the initial numbers of femoral CFU-S were similar for the two strains. The recovery of exogenous CFU-S was much more rapid in STS/A mice than it was in BALB/cHeA mice after 4 Gy of X-irradiation. Furthermore, spleen colonies produced by the transfusion of STS/A marrow cells into syngeneic recipients were significantly larger than those produced by BALB/cHeA marrow cells, regardless of whether the mice used for sources of marrow cells had been irradiated. But, there was no such difference when unirradiated marrow cells from the two strains were transfused into (BALB/cHeA X STS/A) F1 recipients. These results indicate the possible contribution of a host factor (s) that stimulates the growth of spleen colonies after radiation to the radioresistance of STS/A mice, in addition to the primary effect of higher number of survivals of endogenous and exogenous CFU-S in STS/A mice.

Radiation-induced lymphomas in MSM, (BALB/cHeA x MSM) F1 and (BALB/cHeA x STS/A) F1 hybrid mice.

M.MOL-MSM (MSM) mice derived from Mus musculus molossinus progenitors showed extreme resistance to the induction of lymphomas following whole-body X-irradiation with four doses of 1.7 Gy. (BALB/cHeA x MSM) F1 mice between a high lymphoma strain, BALB/cHeA and the MSM showed a high incidence of radiation-induced lymphomas which was quite similar to that in BALB/cHeA mice, but the latent period was prolonged in the hybrids. Susceptibility in incidence was dominant over resistance in these crosses. Incidences of (BALB/cHeA x MSM)F1 hybrids irradiated with four doses of 2.5 Gy X-rays were 77% in females and 88% in males. F1 hybrids between BALB/cHeA and another resistant strain STS/A, (BALB/cHeA x STS/A) F1, also showed a high level of susceptibility, that is, lymphoma incidence was 64% in females and 63% in males. The mean latent period in the (BALB/cHeA x STS/A) F1 hybrids was similar to that in (BALB/cHeA x MSM) F1 hybrids. As all cases of tumors developed in F1 hybrids are informative concerning the detection of the loss of heterozygosity in the loci depending on the combination of two parental strains, the radiation-induced lymphomas obtained from (BALB/cHeA x MSM) F1 and (BALB/cHeA x STS/A) F1 hybrids could be useful for fine analysis of the genetic alterations involved in lymphomagenesis.

Anxiety and pain suppress the natural killer cell activity in oral surgery outpatients.

OBJECTIVE: Psychological stress has an influence on natural killer cell (NK) activity, which plays a central role in protection against microbial infection and cancer. Anxiety concerning cancer is a typical type of psychological stress observed in patients and is associated with various diseases. In this study, we examined whether anxiety about cancer reduces the NK activity or quality of life (QOL), or both, of outpatients. PATIENTS AND METHODS: NK activity was determined by means of a 4-hour 51 chromium-release assay, and a QOL questionnaire by the World Health Organization called QOL-BRIEF was also used. One hundred forty-four patients were asked a variety of questions about anxiety with respect to cancer and pain on their first visit to the outpatient clinic of our Department of Oral Surgery. RESULTS: The NK activity in patients with anxiety about cancer was significantly lower (P < .001) than that in those with no such anxiety. In contrast, NK activity was not influenced by any other factor tested, including differences in diseases and QOL scores. CONCLUSION: Anxiety about cancer may be one of the primary factors for suppression of NK activity in oral surgery outpatients.

Ultrasound biomicroscopy dark room provocative testing: a quantitative method for estimating anterior chamber angle width.

PURPOSE: To describe a quantitative method for measuring the iridocorneal angle recess area, and, using this, to evaluate factors associated with appositional angle-closure during dark room provocative testing using ultrasound biomicroscopy (UBM). METHODS: All patients (178 patients, 178 eyes) with clinically narrow angles referred for UBM dark room provocative testing between September 1996 and March 1998 were enrolled in this study. Images of the inferior quadrant of the angle taken under standardized dark and light conditions were analyzed. The angle recess area (ARA) was defined as the triangular area demarcated by the anterior iris surface, corneal endothelium, and a line perpendicular to the corneal endothelium drawn from a point 750 microm anterior to the scleral spur to the iris surface. ARA, and acceleration and gamma-intercept of the linear regression analysis of the ARA were calculated. In the linear regression formula, y = ax + b, the acceleration a describes the rate at which the angle widens from the scleral spur; the y-intercept b describes the distance from the scleral spur to the iris. RESULTS: Under dark conditions, the angles in 99 patients (55.6%) showed evidence of appositional angle-closure during testing. ARA (0.11 +/- 0.04 vs. 0.15 +/- 0.05 mm2, P < .0001, Student t-test), acceleration a (0.22 +/- 0.15 vs. 0.26 +/- 0.17, P = .068), and y-intercept b (66 +/- 46 vs. 92 +/- 47 microm, P = .0003) were smaller in eyes that were occluded. In the eyes that were not occluded, y-intercept b showed no significant difference between light and dark conditions (P = .1, paired t-test), while acceleration a did (P < .0001). In the eyes that were occluded, both decreased significantly under dark conditions (P < .0001). CONCLUSIONS The ARA linear regression formula provides useful quantitative information about angle recess anatomy. The more posterior the iris insertion on the ciliary face, the less likely the provocative test will be positive.

Angle recess area decreases with age in normal Japanese.

PURPOSE: To investigate prospectively the relationships between anterior chamber angle configuration and refractive error, axial length, age, and body height in the Japanese. METHODS: We studied 65 eyes of 65 subjects (30 men, 35 women) who were either patients at the Ophthalmology Department of Mie University or volunteers. The 65 subjects underwent a complete eye examination, A-scan biometry, and ultrasound biomicroscopy. Images were exported to an IBM-compatible personal computer in PCX format. The angle recess area (ARA) was measured using a software program of our own design. RESULTS: The ARA decreased with age in all quadrants of all eyes. In older individuals, the angle in the superior quadrant was significantly narrower than in the other quadrants. The ARA correlated directly with anterior chamber depth (P < .001), axial length (P < .001), and body height (P = .003), and inversely with age (P < .001) and refractive error (P = .003) in pairwise analysis. Multivariate analysis revealed a significant association between ARA and anterior chamber depth (P < .001), axial length (P = .016), and younger age (P = .043). CONCLUSIONS: The anterior chamber area narrows with age, especially in the superior quadrant. Narrowing of the angle in Japanese is associated with older age, shorter axial length, and shallower anterior chamber depth. We hypothesize that because of the increasing prevalence of axial myopia in younger Japanese, angle-closure glaucoma could become less common in Japan in the future.

A new variant of the Es-1 locus in the rat.

A new prealbumin plasma esterase was demonstrated by the use of miniaturized polyacrylamide slab gel electrophoresis. Genetic analysis indicated that the new variant is controlled by the Es-1 locus and this gene was designated Es-1c. Among 11 rat strains only one strain, WJ, possessed the gene. Two random-bred stocks, Jcl:Wistar and Jcl:SD, also maintained it in their populations. Miniaturized polyacrylamide slab gel electrophoresis showed that the ES-1 band consisted of two close bands with the cathodal one staining darker.

Hereditary erythroblastic anaemia in the laboratory mouse.

Hereditary erythroblastic anaemia was found in a homozygous mutant (hea/hea) of an inbred strain CFO, which originated from noninbred CF#1 mice from Carworth Inc. This newly-described anaemia is inherited as an autosomal recessive and is lethal at 15-25 days of age. Erythrocytes of anaemic mice show striking polychromasia, anisocytosis, and poikilocytosis. One of the most marked features of this anaemia is the presence of large numbers of nucleated cells, mainly orthochromatophilic erythroblasts and myeloid cells, in the circulation. They also include immature erythroid and myeloid cells. Many naked nuclei appear on smears from circulating blood of anaemic infants. Erythrocytes, haematocrit percentage, and haemoglobin content of older anaemic infants were only about 50% of those of the normal. Formation of erythroid, myeloid cells, and megakaryocytes in the bone marrow seems to be progressively affected by mutant alleles in the anaemic infants.

A new hereditary cataract mouse with lens rupture.

A new cataract model originated in a recombinant inbred (RI) strain, CXS4 or CXSD (D), between BALB/cHeA(BALB/c or C) and STS/A(STS or S) mice. Opacity appeared as a white pinpoint focus in unpigmented eyes of albino mice from 5 weeks old. All the mice were bilaterally affected by 14 weeks old. They were fully viable and fertile. There was no sex difference in incidence of cataract. Histologically, the 3-4 months old mice showed vacuoles in the lens cortex. The vacuoles were spread all over the lens cortex in advanced cases. Ruptures of the lens nucleus to the vitreous chamber was a typical occurrence. For elucidation of the mode of inheritance, F1 hybrids (CXD and SXD) and backcross progenies [(CXD)F1XD and (SXD)F1XD] were analysed. No affected mice were observed in F1 hybrids. In backcross progenies, the segregation ratio of affected and normal mice was close to 1:1 in both matings. We conclude that the cataract is inherited by an autosomal single recessive gene. This mutant gene is provisionally named 'lens rupture 2' (gene symbol 1r2, Mouse Genome Database Accession No. MGD-JNUM-37399). The new cataract model mouse will be a good tool for the genetic analysis and molecular biological study of cataractogenesis.