Evaluation of the catabolic activity of cartilage by measurement of serum keratan sulfate concentration in foals

OBJECTIVES

To determine keratan sulfate (KS) concentration in the serum of foals at the early stage of growing, and to evaluate the role of serum KS as a cartilage catabolic marker, comparing its values with the fluctuation of serum alkaline phosphatase (ALP) activity as a measurement of osteoblastic activity.

ANIMALS

12 foals with normal growth and 3 foals with joint abnormalities within 18 months after birth.

PROCEDURE

Measurement of KS concentration and ALP activity in serum and radiographic and physical examinations were done.

RESULTS

In all foals, serum KS concentration was high from 1 week after birth to 3 months of age, while serum ALP decreased with aging. The value started to decrease rapidly from 3 to 5 months of age, then gradually reached adult values. During the first 3 months, KS concentration in male foals was significantly higher than that in female foals. In 3 foals which had joint problems, KS concentration was higher than that in normally growing foals at 1 week, and at 1, 2, and 3 months of age.

CONCLUSIONS

Cartilage catabolic activity is higher in developing foals up to 3 months of age, suggesting that the immature joint at this time could be easily affected by any factor of loading. Moreover, though only 3 diseased foals were examined, higher serum KS concentration in these foals suggest that this variable might be a useful measure of joint diseases, even at an early stage of life in foals.

Effects of chitin and its derivatives on the proliferation and cytokine production of fibroblasts in vitro

The effects of chitin and its derivatives on the proliferation of fibroblasts and on the production of cytokines were examined in vitro. Chitin and its derivatives showed almost no acceleratory effect on the proliferation of cultured fibroblasts. On the contrary, high-concentration 500 micrograms ml-1) D-glucosamine cultures supplemented with or without a 10% fetal calf serum (FCS) supplementation showed a significant (P < 0.05) reduction in the rate of proliferation of L929 fibroblast cells relative to control. High-concentration chitosan cultures supplemented with 10% FCS showed a significant (P < 0.05) reduction in the rate of L929 fibroblast proliferation. However, the inhibition of cell proliferation by high concentrations of chitosan did not show in cultures without FCS. Interleukin-8 (IL-8) was induced in the supernatants of rat primary cultured dermal fibroblasts stimulated with chitin and its derivatives. Chitin and its derivatives did not stimulate the production of IL-6 by mouse dermal primary cultured fibroblasts. IL-1 alpha, IL-1 beta and tumour necrosis factor-alpha were not detected in the fibroblast supernatants. These observations support the notion that cell proliferation is accelerated indirectly by chitin and its derivatives when these materials are used in vivo. In vivo findings of a angiogenesis and migration of neutrophils may be due to persistent release of IL-8 from fibroblasts.

The effect of aging on bone formation in porous hydroxyapatite: biochemical and histological analysis

The effect of aging on osteoblastic differentiation of marrow stromal stem cells was examined. Porous hydroxyapatite (HA) disks were soaked in cells suspensions of bone marrow cells from young (8 weeks) and old rats (60 weeks) and then implanted subcutaneously in syngeneic young and old rats. The bone marrow/HA composites were harvested 8 weeks later, and the contents of bone Gla protein (BGP) and alkaline phosphatase (ALP) activity in them were determined. Histologically, bone formation could be detected in all the composites in young recipient rats; however, some old bone marrow/HA composites in old recipients did not show bone formation and the bone volume in the young bone marrow/HA composites was greater than in the old bone marrow/HA composites. The ratios of ALP activities of young bone marrow/HA composites to old bone marrow/HA composites in young and old recipients were about five times and four times, respectively. The ratios of BGP contents of young bone marrow/HA to old bone marrow/HA composite in young and old recipients were about nine and eight times, respectively. The results suggest that the decreased bone formation observed in old bone marrow cells was due to a smaller population of stromal cells and/or decreased capacity of differentiation of stromal stem cells into osteogenic cells.

CD45 regulates Src family member kinase activity associated with macrophage integrin-mediated adhesion

BACKGROUND

Adhesion of leukocytes to the extracellular matrix and to other cells is mediated by members of the integrin family of adhesion molecules. Src family kinases are activated upon integrin-mediated adhesion. In lymphocytes, CD45 is a leukocyte-specific transmembrane protein tyrosine phosphatase that activates Src family kinases associated with B-cell and T-cell antigen receptor signaling by constitutive dephosphorylation of the inhibitory carboxy-terminal tyrosine phosphorylation site. Here, we show that CD45 is also important in downregulating the kinase activity of Src family members during integrin-mediated adhesion in macrophages.

RESULTS

We found that CD45 colocalized with beta2 integrin and the Src family kinase p53/56(lyn) to adhesion sites in bone marrow-derived macrophages. Macrophages from CD45(-/-) mice were unable to maintain integrin-mediated adhesion. In adherent macrophages, absence of CD45 led to the hyperphosphorylation and hyperactivation of p56/59(hck) and p53/56(lyn), but not of p58(c-fgr). CD45 directly inactivated p59(hck) but not p56(lck) in transient transfection assays. Furthermore, coexpression of CD45 with p59(hck) or p56(lyn) containing a tyrosine to phenylalanine mutation at the carboxy-terminal negative regulatory site resulted in decreased tyrosine phosphorylation of the Src family member kinases due to dephosphorylation of the potentiating tyrosine phosphorylation site within the kinase domain.

CONCLUSIONS

Using primary bone marrow macrophages, these studies demonstrate that CD45 regulates Src family kinases and is required to maintain macrophage adhesion. CD45 decreases Src family kinase activity by dephosphorylating the tyrosine residue located within the kinase domain.

Increased serum concentration of soluble CD30 in patients with Graves' disease and Hashimoto's thyroiditis

This study investigated serum levels of the soluble form of CD30 (sCD30), which is mainly secreted from T helper 2(Th2) cells, in autoimmune thyroid diseases. The possible relationship of sCD30 to autoantibody production was also evaluated. Serum levels of sCD30 were determined by an enzyme-linked immunosorbent assay in 71 patients with Graves' disease, 37 patients with Hashimoto's thyroiditis, and 21 normal donors. Compared with normal subjects (7.1 +/- 4.5 U/mL), sCD30 was increased in patients with Graves' disease (29.2 +/- 25.2 U/mL, P < 0.0001) and in patients with Hashimoto's thyroiditis (29.9 +/- 26.9 U/mL, P < 0.0001). In Graves' disease, sCD30 levels were higher in thyrotoxic patients (41.7 +/- 31.2 U/mL, P < 0.001) than in remission patients (15.8 +/- 11.0 U/mL), and a significant correlation was observed between sCD30 levels and serum activities of TSH receptor antibody (r = 0.444, P < 0.0001). In Hashimoto's thyroiditis, sCD30 levels were higher in patients with transient destructive thyrotoxicosis caused by the aggravation of the disease (48.8 +/- 34.4 U/mL, P < 0.05) than in euthyroid patients (24.2 +/- 19.4 U/mL). These data suggest that serum sCD30 is a valuable marker of disease activity and support an important role of the Th2-type immune response in the pathogenesis in Graves' disease and Hashimoto's thyroiditis.

Duration of chronic HCV infection and efficacy of interferon in chronic hepatitis C patients with a history of blood transfusion. The Study Group for Treatment of Hepatitis in the Kyushu Area

To investigate correlations between the interval between blood transfusion and the start of IFN therapy, and IFN efficacy, we studied chronic hepatitis C patients with a history of blood transfusion. The subjects were 122 patients with chronic hepatitis C and a history of blood transfusion at 64 institutions. The patients were treated with high or low-dose IFN. High-dose therapy consisted of intramuscular injection of human lymphoblastoid interferon (HLBI), 6 x 10(6) IU daily for 2 weeks, then 3 times a week for 22 weeks, and low-dose interferon therapy of intramuscular injection of HLBI, 6 x 10(6) IU daily for 2 weeks, then 3 x 10(6) IU 3 times a week for 22 weeks. Normal serum ALT levels for 6 months or more after completing IFN (complete response) were found in 44/122 (36.2%) patients and HCV RNA was no longer detectable after completing IFN therapy in 19/68 (27.9%). Patients in whom the interval between blood transfusion and the start of IFN therapy was less than 20 years had significantly higher rates of HCV RNA-negative complete response than those in whom the interval was 20 years or more (p < 0.039). When chronic HCV infection is caused by blood transfusion, the efficacy of IFN depends on the duration of chronic HCV infection. Since the duration of HCV infection is a factor in predicting efficacy, early IFN therapy may be more effective.

Comparison of systemic and renal hemodynamics measured by Doppler ultrasonography in canine experimental hypovolemia

The aim of this study was to examine renal hemodynamics at the hypovolemic and recovery phases in two different hypovolemic shock models using Doppler ultrasonography, and to compare this with systemic hemodynamics. In experiment 1, the hypovolemic phase was induced in 6 mongrel dogs by removing arterial blood at 30 ml/kg for 60 min. In the recovery phase, this blood was reinfused at 30 ml/kg over 60 min. In experiment 2, hypovolemia was induced in 12 beagle dogs by rapid blood removal until blood pressure decreased to 40 mmHg and was maintained at this pressure for 30 min. Six of the dogs were then infused with 20 ml/kg hydroxyethyl starch over 5 min, and the other 6 were infused with 60 ml/kg lactated Ringer's solution also over 5 min. Parameters for systemic and renal hemodynamics were measured by using a polygraph and the Doppler method, respectively. The decrease of diastolic blood flow, resulted in an increase of vessel resistance, and was detected in the hypovolemic kidney by the Doppler method. The rapid and large volume infusion of resuscitation fluids was effective for the recovery of both systemic circulation and renal blood flow, however this induced an increase of kidney vessel resistance, a result of the autoregulation mechanism of the kidney. The changes in these parameters at the main renal artery and interlobar artery were similar.

Failure to down-regulate Bcl-2 protein in thymic germinal center B cells in myasthenia gravis

The most unusual characteristic of myasthenia gravis (MG) is that the thymus has germinal centers (GC). Cultured thymic lymphocytes from MG patients spontaneously produce anti-acetylcholine receptor antibodies, indicating that autoreactive B cells have escaped negative selection. To investigate the underlying mechanism, we examined the expression of the apoptosis-related protein Bcl-2 in GC B cells (defined as CD19+ CD38+ cells) in the thymus in 14 MG patients using three-color flow cytometry. GC in MG patients did not show the normal down-regulation of Bcl-2 (the frequency of Bcl-2+ GC B cells in the MG thymus and in control tonsils 54.3 +/- 16.2% versus 20.6 +/- 8.0%; mean +/- SD. p < 0.0001). In contrast, Bcl-2 in GC in the mediastinal lymph nodes from four patients was down-regulated to a relatively normal level. Using the terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end-labeling (TUNEL) method to detect DNA fragmentation in situ, the frequency of TUNEL+ cells in GC in the MG thymus was lower than in control tonsils. These results suggest that autoreactive B cells which normally undergo apoptosis in GC may survive because of Bcl-2 up-regulation in this unusual location.

Purification and characterization of the flagellar hook-basal body complex of Bacillus subtilis

The flagellar hook-basal body (HBB) complex of the Gram-positive bacterium Bacillus subtilis was purified and analysed by electron microscopy, gel electrophoresis, and amino acid sequencing of the major component proteins. The purified HBB complex consisted of the inner (M and S) rings, a rod and a hook. There were no outer (P and L) rings that are found in Gram-negative bacteria. The hook was 15 nm in thickness and 70 nm in length, which is thinner and longer than the hook of Salmonella typhimurium. The hook protein had an apparent molecular mass of 29 kDa, and its N-terminal sequence was identical to that of B. subtilis FIgG, which was previously reported as a rod protein. The sequence of the reported FIgG protein of B. subtilis is more closely related to that of FIgE (the hook protein) rather than FIgG (the rod protein) of S. typhimurium, in spite of the difference of the apparent molecular masses between the two hook proteins (29 kDa versus 42 kDa). The hook-basal body contained six major proteins (with apparent molecular masses of 82, 59, 35, 32, 29 and 20 kDa) and two minor proteins (23 kDa and 13 kDa), which consistently appeared from preparation to preparation. The N-terminus of each of these proteins was sequenced. Comparison with protein databases revealed the following polypeptide-gene correspondences: 82 kDa, fIiF; 59 kDa, fIgK; 35 kDa, orfF; 32 kDa, yqhF; 23 kDa, orf3 of the fIaA locus; 20 kDa, fIgB and fIgC; 13 kDa, not determined. The band at 20 kDa was a mixture of FIgB and FIgC, as revealed by two-dimensional gel analysis. Characteristic features of B. subtilis HBB are discussed in comparison with those of S. typhimiurium.

Immunohistochemical evidence of insulin-like growth factor II in human small hepatocellular carcinoma with hepatitis C virus infection: relationship to fatty change in carcinoma cells

It has recently been reported that insulin-like growth factor II (IGF-II) may play a role in the pathogenesis of hepatocellular carcinoma (HCC). We studied the relationship between the expression of IGF-II and fatty change in human small HCC using immunohistochemical staining techniques. Liver biopsy specimens were obtained from 35 patients with HCC (consisting of 15 patients with fatty change and 20 patients without fatty change). All patients had serum markers for the hepatitis C virus (HCV) and histological findings obtained from non-tumourous lesions showed liver cirrhosis or chronic active hepatitis. Immunohistochemical staining was performed using a monoclonal antibody against rat IGF-II. A positive immunoreaction was found in 69% (24/35) of HCC. Insulin-like growth factor II was immunodetected in 80% (12/15) of HCC with fatty change but only in 60% (12/20) of those without fatty change. In most cases, IGF-II was not found in hepatocytes from non-tumourous lesions. We believe this to be the first time that IGF-II has been detected immunohistochemically in small HCC derived from HCV infection. This growth factor was more frequently immunodetected in HCC with fatty change than without. As insulin is an essential factor for the metabolism of fatty acids, IGF-II may play an important role in both fatty degeneration and in the proliferation of HCC cells. Furthermore, immunohistochemical IGF-II staining may contribute to the diagnosis of HCC, particularly in early stages accompanied by fatty change.

Case report: eosinophilic colitis with high antibody titre against Ascaris suum

Eosinophilic gastroenteritis (EGE) is an inflammatory disease characterized by eosinophilic infiltration of the gastrointestinal tract accompanied by varying abdominal symptoms and usually by peripheral blood eosinophilia. Although the precise aetiology of EGE remains to be determined, contribution of allergic process to certain allergens, such as foods, drugs and parasites, has been repeatedly proposed as the pathogenesis of the disease. Here we report on a rare case of a woman who had extensive eosinophilic infiltration in the descending and rectal colon with a high titre of IgG antibody against Ascaris suum. The patient was successfully treated with prednisolone.

Co-localisation of insulin-like growth factor II and the proliferation marker MIB1 in hepatocellular carcinoma cells

AIM

To assess the effect of insulin-like growth factor II (IGF-II) on proliferation of hepatocellular carcinoma (HCC) cells.

METHODS

Expression of IGF-II mRNA and protein was detected in 10 archival HCC specimens using in situ hybridisation and immunohistochemistry, respectively. Expression of the Ki-67 antigen, a proliferation marker, was determined immunohistochemically on the same sections.

RESULTS

Increased expression of IGF-II mRNA and protein was detected in five of the 10 HCCs in cells located at the periphery of tumour nests. The pattern of localisation of IGF-II was almost identical with that of Ki-67 antigen.

CONCLUSIONS

Most of the Ki-67 antigen positive cells co-expressed IGF-II, suggesting that IGF-II may act as an autocrine or paracrine growth factor, and may play an important role in the development of HCC.

Risk factors for hemorrhage from gastric fundal varices

The incidence and the risk factors of hemorrhage from gastric fundal varices (FV) have not been fully evaluated. We therefore conducted a retrospective and prospective study to define the incidence and risk factors for such episodes. We investigated 132 patients with cirrhosis and gastric FV. Of these 132 patients, 15 patients had hemorrhagic FV at the time of enrollment. The clinical characteristics were compared between these patients and those without a first hemorrhage from FV. In the patients who had never previously bled, the incidence and risk factors were prospectively investigated. The size of FV was greater and red-spot on the FV were more prevalent in patients with hemorrhagic FV. Child's status was also more severe in these patients. In the 117 patients who had never bled, 34 hemorrhages from FV occurred during the follow-up period. The cumulative risk for such hemorrhage at 1, 3, and 5 years was 16%, 36%, and 44%, respectively. A multiple regression analysis (Cox's model) revealed the size of varices, red-spot on the FV, and Child's status to be statistically significant, as well as independent predictors for hemorrhage from FV. The endoscopic criteria (size of the largest varix and presence of red-spot), as well as the hepatic functional reserve, provide the most essential information for predicting a hemorrhage from FV. An estimation of the probability for hemorrhage from FV based on Cox's model may therefore be beneficial in the clinical management of patients with high-risk FV.

Consideration of the optimum pH for the analysis of serum p-phenylenediamine oxidase activity in thoroughbred horses

The optimum pH for the measurement of serum p-phenylenediamine oxidase (Ox) activity was given (pH 6.6), and the relationship between serum ceruloplasmin (Cp) concentration and its Ox activity was established in healthy adult horses. In adult horses, serum antigenic Cp concentrations were measured by the single radial immunodiffusion (SRID) method with the affinity-purified antibody to equine plasma Cp and compared with its Ox activity. Efficient co-relation between Cp concentration and Ox activity in the sera (r = 0.93) and its Ox/Cp ratio were given. These results might contribute to the calculation of antigenic Cp concentration from its Ox activity, the analysis of holo-Cp content in serum, and the research for copper metabolism in thoroughbred horses.

Risk factors for hemorrhage from gastric fundal varices

The incidence and the risk factors of hemorrhage from gastric fundal varices (FV) have not been fully evaluated. We therefore conducted a retrospective and prospective study to define the incidence and risk factors for such episodes. We investigated 132 patients with cirrhosis and gastric FV. Of these 132 patients, 15 patients had hemorrhagic FV at the time of enrollment. The clinical characteristics were compared between these patients and those without a first hemorrhage from FV. In the patients who had never previously bled, the incidence and risk factors were prospectively investigated. The size of FV was greater and red-spot on the FV were more prevalent in patients with hemorrhagic FV. Child's status was also more severe in these patients. In the 117 patients who had never bled, 34 hemorrhages from FV occurred during the follow-up period. The cumulative risk for such hemorrhage at 1, 3, and 5 years was 16%, 36%, and 44%, respectively. A multiple regression analysis (Cox's model) revealed the size of varices, red-spot on the FV, and Child's status to be statistically significant, as well as independent predictors for hemorrhage from FV. The endoscopic criteria (size of the largest varix and presence of red-spot), as well as the hepatic functional reserve, provide the most essential information for predicting a hemorrhage from FV. An estimation of the probability for hemorrhage from FV based on Cox's model may therefore be beneficial in the clinical management of patients with high-risk FV.

Anxiety, depression and psychosomatic symptoms in patients with atopic dermatitis: comparison with normal controls and among groups of different degrees of severity

Atopic dermatitis is a common skin disorder. The age distribution is mainly located from infancy to adolescence, which period is the most important for forming character or effecting their psychological condition. We used three types of psychological tests to investigate anxiety, depression and psychosomatic symptoms in 45 patients with atopic dermatitis and 34 normal controls. These tests consisted of the manifest anxiety scale (MAS), self-rating depression scale (SDS) and Cornell Medical Index (CMI). On the MAS, the atopic dermatitis group did not show any statistical difference from normal controls. However, the SDS and the CMI produced statistically significant differences (P < 0.05 and P < 0.01, respectively). Furthermore, we classified their symptom in three degrees of severity (mild: 15; moderate: 14; severe: 16). Patients with mild symptoms did not show any statistical difference from normal controls on the three tests. Patients with moderate symptoms showed a statistically significant difference from normal controls on the SDS (P < 0.01) and the CMI (P < 0.05), but not on the MAS. Finally, patients with severe symptoms (in-patients) produced somewhat lower test scores than those with moderate symptoms. We conclude that the patients with atopic dermatitis were more depressive and psychosomatic symptom-prone than normal controls, and suggest that some patients with atopic dermatitis should be treated both dermatologically and psychiatrically.

Ultrasonography and angiographic examination of normal canine liver vessels

The aim of this study is to provide a description of the ultrasonographic and angiographic anatomy of the hepatic and portal veins in normal dogs. Knowledge of this anatomy is essential for the proper diagnosis and correction of hepatic vessel anomalies like portal systemic shunts. Cranial mesenteric portography was done in 10 adult mongrel dogs to visualize the portal vein and its branches while the hepatic veins were visualized using the transvenous retrograde angiography method. Longitudinal and transverse ultrasound scans of the liver were done in the same dogs in left and right lateral positions in order to determine the best positions for imaging the different liver vessels. The distribution pattern of the hepatic and portal veins could be demonstrated by both ultrasonography and contrast angiography. Hepatic arteries are not usually visualized ultrasonographically. Ultrasound provided dynamic information that could not be obtained by contrast radiography. Super imposition of all vessels in the angiographic studies made the description of the branches of the liver vessels difficult. The results of the present study suggest that both methods may provide important complementary information in the diagnosis and planning of surgical procedures for the correction of vessel anomalies in the canine liver.

Role of Kupffer cell-derived reactive oxygen intermediates in alcoholic liver disease in rats in vivo

The pathophysiology of alcoholic liver disease (ALD) remains largely unknown. In this work, we have developed an experimental rat model to elucidate the mechanism of liver injury, including ALD, in which Kupffer cell-derived reactive oxygen intermediates (ROIs) might be involved. Groups of male Wistar rats were pair-fed on a liquid high-fat diet containing ethanol (36% of total calories) or isocaloric carbohydrate with or without dietary carbonyl iron (0.5% w/v) for 3 weeks. In this rat model, we investigated Kupffer cell-derived ROI generation, which affected hepatocellular injury and hepatic fibrosis in ALD. The production of ROIs in Kupffer cells isolated from the iron-fed, the ethanol-fed, and the ethanol plus iron-fed rats were significantly increased, compared with that in Kupffer cells isolated from control rats (iron > ethanol+iron > ethanol > > control). However, hepatic vitamin E content in the ethanol plus iron-fed rats was decreased rather than that in the iron-fed rats. Then, lipid peroxidation of isolated microsomes was assessed as malondialdehyde equivalents determined by thiobarbituric acid assay. Compared with controls, the malondialdehyde equivalents were elevated in experimental groups (ethanol+iron > ethanol > iron > control). Serum ALT levels were greatly elevated in rats fed a diet containing both ethanol and iron (ethanol+iron > iron > ethanol > control). Hepatic content of hydroxyproline was significantly increased in ethanol plus iron-fed rats, compared with rats other than the ethanol plus iron-fed group (ethanol+iron > iron > ethanol > control). These results suggested that the enhanced Kupffer cell-derived ROI generation could itself contribute to the increased susceptibility to lipid peroxidation, which might cause hepatocellular injury and lead to hepatic fibrosis in ALD.

Osteogenic potential of allogeneic rat marrow cells in porous hydroxyapatite ceramics: a histological study

Hydroxyapatite ceramics facilitate osteogenesis but cannot induce bone formation by themselves. We studied the feasibility of bone formation supported by allogeneic bone marrow cells in porous hydroxyapatite ceramics. Coralline hydroxyapatite discs were soaked in a marrow cell suspension harvested from either ACI (RT1a), Lewis (RT1(1)), or Fischer 344 (RT1(1v)) male rats, and these discs were implanted subcutaneously into 56 male Fischer 344 rats. FK-506 (tacrolimus hydrate), an immunosuppressant, or saline was injected intramuscularly into the recipients every day for 2 weeks after surgery, and additional injections were given to 19 of the rats every 2 days for 2 more weeks. Neither of the mismatched major (ACI rat) or minor (Lewis rat) marrow cell transplants showed any bone formation without administration of FK-506. However, in rats treated with FK-506, bone formed in the pores of all the three types of ceramics implanted, which each contained the marrow cells from one of the three kinds of rats used. There were no differences among the three groups of donors with regard to the bone formation ratio. We previously reported that subcutaneous implantation of porous hydroxyapatite combined with isogeneic marrow cells resulted in consistent bone formation, even at ectopic sites. Since it would be difficult to harvest a large number of autologous marrow cells in clinical cases, we attempted to use allogeneic marrow cells and have shown the allogeneic murine marrow cells to have osteogenic potential.

Enhanced angiogenesis and granulation tissue formation by basic fibroblast growth factor in healing-impaired animals

The effect of basic fibroblast growth factor (bFGF) on angiogenesis and granulation tissue formation in normal and healing-impaired animals was studied. bFGF showed a dose-dependent enhancement of granulation tissue formation in the subcutaneous implantation of a paper disk in normal rats. Application of bFGF restored the formation in healing-impaired rat models treated with steroid, chemotherapy and X-ray irradiation. The angiogenic activity of bFGF was also demonstrated in the micro-pocket assay using the cornea of rabbits. Repeated applications of bFGF accelerated closure of full-thickness excisional wounds in diabetic mice, but the high doses showed rather diminished response. In contrast histological and gross evaluation of wound tissues revealed enhanced angiogenesis and granulation tissue formation in a dose-dependent manner. The findings suggested that the topical application of excess amounts of bFGF might reduce its ability to promote wound closure because of the prolonged responses in both neovascular and granulation tissue formation.

Nitrate kinetics in patients with compensated cirrhosis: correlation with hemodynamics

OBJECTIVES

The serum nitrate concentration is known to be increased in patients with cirrhosis. This study was designed to determine the kinetics of nitrate in the splanchnic vascular areas and its relationship with hepatic hemodynamics in patients with compensated cirrhosis.

METHODS

We measured the serum nitrate concentration of various sites, including the femoral artery, hepatic vein, azygos vein, and pulmonary artery, and compared these values with hepatic hemodynamics.

RESULTS

The nitrate concentrations of hepatic vein and azygos vein were significantly greater in cirrhotic patients compared with those of control subjects. The values were particularly elevated in patients with Child-Pugh's class B. In control subjects, hepatic vein and azygos vein nitrate concentrations were significantly lower than arterial nitrate concentrations whereas nitrate concentrations were significantly greater in the hepatic and azygos veins than femoral artery in cirrhotic patients, and nitrate kinetics was that of the net release of nitrate from the hepatic and azygos veins. The portal vein blood flow positively correlated with the nitrate concentration of azygos vein, pulmonary artery, and femoral artery.

CONCLUSIONS

The present results implicate the enhanced production of nitric oxide in the mesenteric vascular beds in patients with cirrhosis. The positive correlation between portal vein blood flow and serum nitrate concentrations suggests that endogenous nitric oxide may have an important role in the regulation of portal hemodynamics in these patients.

Mechanism of acceleration of wound healing by basic fibroblast growth factor in genetically diabetic mice

To elucidate the role of basic fibroblast growth factor (bFGF) in the wound healing process, we investigated the ability of the factor to modulate an inflammatory reaction at the wound site and to influence endothelial cells and fibroblasts in vitro. A single, topical application of bFGF to a full-thickness wound of genetically diabetic mice caused an increase in the volume of wound exudate in a dose-dependent manner. bFGF induced the infiltration of a large number of leukocytes in the wound exudate. Transforming growth factor-beta (TGF-beta) positive cells, such as macrophages, monocytes and fibroblasts, appeared in the granulation tissue in bFGF-treated diabetic mice. These phenomena were comparable to those in normal animals, suggesting that the treatment with bFGF restored the inflammatory response in wound healing of diabetic mice. The effects of bFGF on cell proliferation, migration and angiogenesis were histologically recognized as shown in enhanced granulation tissue formation and neovascularization. It is suggested that bFGF promotes the recruitment of inflammatory cells into the wound site to induce a cascade reaction of growth factors including TGF-beta in a wound healing process, and so would accelerate wound healing.

Pathogenesis of chagasic myocarditis: an experimental study

With the propose to study the pathogenesis of chagasic myocarditis, white mice were inoculated with the Y strain of Trypanosoma cruzi. After confirmation of parasitemia, the animals were sacrificed: a) in the acute stage (first 30 days), 5 mice/day: b) in the subacute stage (days 30-90), 5 mice/week: c) in the chronic stage the remaining survivors, 365 days after inoculation. Parasitemia appeared on the sixth day and increased gradually until the maximum was reached in the third or fourth week, then decreasing until the thirtieth day, disappearing from the circulation after the 87th day. Parasitism occurred with parasitemia however, without a quantitative relationship. Starting from the sixth post-inoculation day the muscle fibers demonstrated parasites, with the presence of compact or loose amastigote nests. The nests, bursted during the evolution so that their contents (cytokine or interleukin?) could extravasate. While the nest was integral, there was no acute inflammatory reaction. During the chronic stage empty spaces remained and were occupied by the chronic inflammatory process: proliferation of fibroblasts. granulomas and residual fibrosis. The inflammatory edema replaced the interstitium. After rupture of the amastigote nests they were initially invaded by the acute inflammatory process and then by the chronic one with deposition of a fibrin network, proliferation of collagen, mastocytosis and terminating with fibrosis. It was not uncommon to find amastigote nests in various stages during the chronic phase in the myocardial fibers, characterizing the cyclical process of the parasitosis. The blood vessels were also, invaded by parasites. Causing thrombosis and necrotizing arteritis. The autonomous nervous system also was involved, with the presence of amastigote nests, ganglionitis, plexulitis with inflammation in scattered areas.