Changes in mucosal immune cells of bladder tumor patient after BCG intravesical immunotherapy

The Bacillus Calmette-Guerin (BCG) is considered to be at least as effective, and perhaps superior to chemotherapy in the prophylaxis of recurrent superficial tumors. However, the mechanism of the antitumor effect of BCG is still not exactly known. We have conducted investigations to examine changes in bladder mucosal immune cells in patients with superficial bladder carcinoma treated with a first cycle of BCG. The study group included 15 BCG and 5 doxorubicin instillation patients, most in the intermediate or high risk group for recurrent tumor. Grossly normal bladder mucosal cold cup biopsies were performed at initial TUR and one week after six consecutive weekly instillations of BCG or doxorubicin. All specimens underwent immunohistochemical staining, both pre-treatment and post-treatment, including CD20, CD45RO, CD8, CD4 and CD57. Immunoreactive cell counts were evaluated from three different microscopic fields (x400) under the grid. The mean duration of follow-up was 52.8 months. The post-treatment bladder mucosal B-cells (CD20) and T-cells (CD45RO, CD4, CD8) were significantly increased compared to pre-treatment in patients treated with BCG instillation, but NK-cells (CD57) were not changed. However, there was no change in B-cells or T-cells in patient treated with doxorubicin. The CD20 cells in pre-treatment specimens did not correlate with any other cells. However, it was a statistically significant correlation with CD45RO in post-treatment specimens. The CD4 correlated with CD45RO and CD8 in pre-treatment, but it was correlated with CD45RO and CD57 in post-treatment specimens. There was no tumor recurrence in cases with significantly increased B-cells after BCG instillation. The results of these studies suggest that intravesical BCG immunotherapy for superficial bladder tumor induces a significant increase in T-cells as well as B-cells and that B-cells have a preventive effect on tumor recurrence. Further studies with a larger number of patients are needed to confirm the value of the B-cell increment after BCG instillation as a clinically independent prognostic factor.

Opacification of the intrahepatic portal veins during CT hepatic arteriography

PURPOSE

The purpose of this study was to ascertain the cause of opacification of the portal veins during CT hepatic arteriography (CTHA).

METHOD

A total of 155 consecutive patients with hepatocellular carcinoma were evaluated with CTHA as preoperative staging. The opacification of the portal veins during CTHA was categorized as opacification of the main portal vein, right or left branches of the main portal vein (generalized), and segmental or subsegmental portal veins (localized). Hepatic angiography was compared and possible causes were evaluated.

RESULTS

One hundred eight (70%) of 155 patients showed intrahepatic portal vein opacification at CTHA: generalized in 60 patients (39%) and localized in 48 patients (31%). Intrahepatic causes were arterioportal shunts due to hepatocellular carcinoma in 20 (19% of 108 patients), previous liver biopsy in 9 (8%), and portal vein thrombosis in 4 (4%). Extrahepatic cause was counted in 57 cases (53%) and was due to inflow of contrast material via nonmesenteric portal circulation through the gastric antrum, duodenum, and/or pancreas.

CONCLUSION

Intrahepatic portal veins are frequently opacified during CTHA, and the causes were arterioportal shunts through hepatocellular carcinoma, postbiopsy shunt, portal vein thrombosis, and inflow of contrast material via the nonmesenteric portal circulation.

An outbreak of meningitis caused by Angiostrongylus cantonensis in Kaohsiung

Eight Thai laborers developed meningitis after eating raw snails (Ampullarium canaliculatus) during the period from September 27 to October 6, 1998. The diagnosis of Angiostrongylus cantonensis infection was established in all patients by serologic studies of serum and cerebral spinal fluid (CSF). Clinical manifestations included meningitis, radiculitis and cranial nerve palsy. Symptoms included fever, headache, orbital pain, gastrointestinal upset, hyperesthesia, muscle weakness, skin rash and diplopia. Laboratory abnormalities included peripheral eosinophilia, CSF eosinophilia, transient elevation of liver enzymes and creatinine phosphokinase, elevation of IgE. No space occupying lesions were detected by magnetic resonance imaging of the brain. None of the patients developed severe sequelae during the 6-month follow-up except for occasional headache in one patient. This report also provides evidence that third stage larvae were present in the intermediate host, A. canaliculatus, which the laborers had eaten.

Novel target sites for estrogen action in the dorsal hippocampus: an examination of synaptic proteins

Structural studies have shown that estrogens increase dendritic spine number in the dorsal CA1 field of rat hippocampus using Golgi impregnation as well as the number of dorsal CA1 synapses visualized via electron microscopy. The present study was carried out to further these findings by examining changes in the levels of pre- and postsynaptic proteins using radioimmunocytochemistry (RICC). In this study, 2 days of estradiol-benzoate treatment produced significant and comparable increases in synaptophysin, syntaxin, and spinophilin immunoreactivity (IR) in the CA1 region of the dorsal hippocampus of ovariectomized female rats. For spinophilin, IR was also increased in the hilar region of the dentate gyrus as well as CA3. In all cases, the nonsteroidal estrogen antagonist CI628, which has been previously shown to block spine formation, inhibited the effects of estrogen. However, these protein differences were not detected in whole hippocampus using Western blots. These findings add to a growing body of evidence that estrogens increase synapses in the CA1 region of hippocampus along with changes in previously unidentified sites. These results also suggest that RICC is a rapid and sensitive method for examining molecular changes in synaptic profiles in anatomically distinct brain regions.

Discrepancies between patient and physician estimates for the success of stem cell transplantation

CONTEXT

Stem cell transplantation is associated with considerable morbidity and mortality. The extent to which patients and their physicians correctly estimate these risks is unknown.

OBJECTIVE

To measure the expectations of patients and physicians prior to stem cell transplantation and correlate them with actual outcomes after transplantation.

DESIGN

Prospective cohort study with baseline questionnaire administered July 1996 through November 1999 and follow-up to May 2000.

SETTING

Tertiary care transplant center in the United States.

PARTICIPANTS

Of 458 surveys mailed, evaluable returned surveys were included for 313 autologous and allogeneic stem cell transplantation patients and their physicians.

MAIN OUTCOME MEASURES

Patient and physician expectations prior to transplantation (measured on 6-point Likert scales) of treatment-related mortality, cure with transplantation, and cure without transplantation; actual treatment-related mortality and disease-free survival among patients with at least 1 year of follow-up after transplantation (n = 263).

RESULTS

Both patients and physicians were fairly accurate in estimating treatment-related mortality when actual mortality was less than 30%. However, in situations in which mortality was higher than 30%, such as with allogeneic transplantation for intermediate or advanced disease, physician expectations were lower, while patients remained optimistic. Similarly, physicians provided lower estimates of disease-free survival in cases of intermediate or advanced disease while patient expectations remained high and constant regardless of disease stage.

CONCLUSIONS

Patients and their physicians have the most concordant and accurate expectations when the outcome of stem cell transplantation is likely to be favorable. However, patients with more advanced disease fail to recognize the higher risks associated with their situations.

Tachycardias in infants, children and adolescents: safety and effectiveness of radiofrequency catheter ablation

Radiofrequency catheter ablations provide an effective control of a variety of supraventricular and ventricular tachycardias in adults. This study was designed to evaluate the efficacy and safety of radiofrequency catheter ablations in infants, children and adolescents. Ninty-three ablations were performed in 84 patients ranging from 5 months to 18 years of age. All but 1 patient were successfully treated (98.8%). Two patients required 1 and 2 additional attempts to achieve success. Tachyarrhythmic episodes recurred in 4 patients within 1-5 months after ablation, which were successfully treated by repeating the intervention. Significant complications occurred in 3 of the ablations (3.2%). Although radiofrequency ablations are very effective and safe in pediatric patients, indications should be restricted in patients younger than 4 years because of a higher risk of possibly life-threatening complications.

High-resolution mapping of the blood pressure QTL on chromosome 7 using Dahl rat congenic strains

It was previously shown using Dahl salt-sensitive (S) and salt-resistant (R) rats that a blood pressure quantitative trait locus (QTL) was present on rat chromosome 7. In the present work, this QTL was localized to a region less than 0.54 cM in size on the linkage map using a series of congenic strains. This region was contained in a single yeast artificial chromosome that was 220 kb long. This small segment still contained the primary candidate locus Cyp11b1 (11beta-hydroxylase), but the adjacent candidate genes Cyp11b2 (aldosterone synthase) and Cyp11b3 were ruled out. It is concluded that 11beta-hydroxylase, through its known genetic variants altering the production of 18-hydroxy-11-deoxy corticosterone, is very likely to account for the blood pressure QTL on chromosome 7 in the Dahl rat model of hypertension. This QTL accounts for about 23 mm Hg under the condition of 2% NaCl diet for 24 days.

First observation of the sigma(*+)(c) baryon and a new measurement of the sigma(*+)(c) mass

Using data recorded with the CLEO II and CLEO II.V detector configurations at the Cornell Electron Storage Rings, we report the first observation and mass measurement of the Sigma(*+)(c) charmed baryon, and an updated measurement of the mass of the Sigma(+)(c) baryon. We find M(Sigma(*+)(c))-M(Lambda(+)(c)) = (231.0+/-1.1+/-2.0) MeV, and M(Sigma(+)(c))-M(Lambda(+)(c)) = (166.4+/-0.2+/-0.3) MeV, where the errors are statistical and systematic, respectively.

Infantile hemangioendothelioma treated with high dose methylprednisolone pulse therapy

Infantile hemangioendothelioma is a severe disease with a high mortality. It is characterized by multiple hemangioma affecting the skin and visceral organs. We report that high doses of methylprednisolone pulse therapy improved symptoms and signs of infantile hemangioendothelioma in a male neonate, and completely resolved the hepatic and cutaneous hemangioendothelioma on follow up.

Lower gastrointestinal bleeding due to cytomegalovirus ileal ulcers in an immunocompetent man

Cytomegalovirus (CMV) infections are commonly reported in severely immunocompromised hosts and ulcers of the alimentary tract are frequently observed in systemic CMV infections. However, invasive and ulcerative disease of the gastrointestinal (GI) tract caused by CMV has also been reported in healthy adults. Many reports show that a CMV infection can produce localized ulcerations in the esophagus, stomach, small intestine, and colon in nonimmunocompromised individuals. The most common site of involvement by CMV infection in the GI tract is the colon followed by the upper GI tract and the least common site is the small intestine. Although GI bleeding is one of the major presenting symptoms of patients with CMV infections of the GI tract, lower GI bleeding due to CMV ileal ulcers in immunocompetent patients, to our knowledge, has not been reported in the English literature. Recently, we experienced a case of lower GI bleeding due to CMV ileal ulcers in a 57-year-old man who had no evidence of immunocompromise. This case suggests that small intestinal ulcers due to CMV infection should be included in the differential diagnosis of lower GI bleeding even in immunocompetent hosts.

Oxidative stress effect on the activation of hepatic stellate cells

Collagen is the most excessive extracellular matrix protein in hepatic fibrosis. Activated, but not quiescent, hepatic stellate cells (HSCs) have a high level of collagen and a smooth muscle actin (alpha SMA) expression. HSCs play a key role in the pathogenesis of hepatic fibrosis. We analyzed a mechanism leading to HSC activation by evaluating the role of oxidative stress and the expression of NFkB. In vitro study HSCs were proliferated (PCNA:2% vs 68%) and activated (alpha SMA: 5% vs 78%) by ascorbate/FeSO4, and HSCs activated by type I collagen were blocked (PCNA: 97% vs 4%, a SMA: 86% vs 9%) by a-tocopherol. In vivo study means of a SMA positive cells in liver at 400 x HPF were 48.3+/-5.2 and 15.2+/-1.8 and [3H]thymidine uptake of HSC was 529.2+/-284.8 cpm and 223.0+/-86.3 cpm in control and a-tocopherol treated group respectively at 32 hours after CCl4 injection. Nuclear extracts from activated, but not from quiescent, HSCs formed a complex with the NFkB cognate oligonucleotidesand alpha-tocopherol inhibited this bindings. This study indicates that oxidative stress plays an essential role through the induction of NFkB on HSC activation.

Gait analysis in advanced Parkinson's disease--effect of levodopa and tolcapone

OBJECTIVE

To determine the therapeutic effect of levodopa/benserazide and tolcapone on gait in patients with advanced Parkinson's disease.

METHODS

Instrumental gait analysis was performed in 38 out of 40 patients with wearing-off phenomenon during a randomized, double-blind, placebo-controlled trial of tolcapone.

RESULTS

Gait analysis disclosed a significant improvement by levodopa/benserazide in walking speed, stride length and the range of motion of hip, knee and ankle joints. At the end of the study, both the UPDRS motor scores during off-period and the percentage of off time improved significantly using tolcapone. However, gait analysis could not confirm this improvement. With respect to levodopa/benserazide effect, the reduction in rigidity correlated with improved angular excursion of the ankle, whereas the decreased bradykinesia correlated with improved stride length and angular excursion of the hip and knee joints.

CONCLUSION

The results of our gait analysis confirmed that in parkinsonian patients with fluctuating motor symptoms levodopa/benserazide, but not tolcapone, produced a substantial improvement.

Optimization of fermentation conditions for the production of bacterial cellulose by a newly isolated Acetobacter sp. A9 in shaking cultures

The optimum fermentation conditions for the production of cellulose by a newly isolated Acetobacter sp. A9 were determined by shaken cultures. The strain was able to produce cellulose at 25-30 degrees C with a maximum at 30 degrees C. Cellulose production occurred at pH 4.5-7.5 with a maximum at pH 6.5. The improved medium composition was 4% (w/v) glucose, 0.1% (w/v) yeast extract, 0.7% (w/v) polypeptone and 0.8% (w/v) Na(2)HPO(4).12H(2)O. Under these culture conditions, 3.8 g/l cellulose was produced after 7 days of cultivation, although this strain produced only 2.2 g/l in the standard medium. The addition of ethanol to the improved medium enhanced cellulose production: in an improved medium containing 1.4% (v/v) ethanol, cellulose production was 15.2 g/l, which was about four times higher than that without ethanol. Addition of ethanol was found to eliminate the spontaneous mutation of Acetobacter sp. A9.

Overexpression of heat-shock protein 25 augments radiation-induced cell-cycle arrest in murine L929 cells

PURPOSE

Protective effect of small heat-shock protein (sHSP) against gamma-radiation, which associated with HSP25-induced cell-cycle delay and Bcl-2 induction. We further extended our studies on the possible role of HSP25 on ionizing radiation-induced cell-cycle regulation.

MATERIALS AND METHODS

Flow-cytometric analyses were performed for cell-cycle distribution and Western blotting. Kinase or immunocomplex kinase assay were performed for detection of cell-cycle protein expression or activation.

RESULTS

Pronounced arrest of G1, S and G2/M phase was observed by 4Gy radiation and these arrests were augmented by hsp25 overexpression. Inhibition of cyclin-D1, and cyclin-E and induction of p21Waf by radiation, which was more pronounced in hsp25 overexpressed cells than control cells, which is associated with increased binding activity of CDK2. S-phase regulator, cyclin-A and its associated CDK2 and CDC2 kinase activities were also increased by irradiation and hsp25 overexpression attenuated these phenomena. In addition, cyclin-B1 expression and its associated kinase activity, which are responsible for the transition of G2 to M phase, were increased by radiation and hsp25 overexpression also decreased these phenomena.

CONCLUSION

HSP25 augmented radiation-induced cell-cycle arrest (G1, S, and G2/M phase) may be caused by the HSP25-mediated cell-growth delay and is associated with radioresistance.

Cloning and characterization of tissue inhibitor of metalloproteinase-3 (TIMP-3) from shark, Scyliorhinus torazame

We cloned the full-length cDNA encoding TIMP-3 from the cartilage of cloudy dogfish, Scyliorhinus torazame. The entire open reading frame was composed of 645 nucleotides and 214 residues including 12 conserved cysteines and asparagine-184, a putative site for N-linked sugars. It showed about 72% identity to those of other species based on the deduced amino acid sequence. The mRNA of shark TIMP-3 were expressed abundantly in brain and cartilage tissues. To investigate the roles of shark TIMP-3, an expression vector was constructed and transfected into HT1080 human fibrosarcoma cells. Overexpression of shark TIMP-3 reduced the activity of MMP-2 in gelatin zymography. Through human Alu PCR based CAM assay, we also confirmed that shark TIMP-3 transfected HT1080 cells had less intravasation effects.

Study of B Decays to Charmonium States: B-->eta(c)K and B --> chi(c0)K

In a sample of 9.66x10(6)B&Bmacr; pairs collected with the CLEO detector we make the first observation of B decays to an eta(c) and a kaon. We measure branching fractions B(B+-->eta(c)K+) = (0.69(+0.26)(-0.21)+/-0.08+/-0.20)x10(-3) and B(B degrees -->eta(c)K degrees ) = (1.09(+0.55)(-0.42)+/-0.12+/-0.31)x10(-3), where the first error is statistical, the second is systematic, and the third is from the eta(c) branching fraction uncertainty. From these we extract the eta(c) decay constant in the factorization approximation, f(eta(c)) = 335+/-75 MeV. We also search for B decays to a chi(c0) and a kaon. No evidence for a signal is found and we set 90% C.L. upper limits: B(B+-->chi(c0)K+)<4.8x10(-4) and B(B degrees -->chi(c0)K degrees )<5.0x10(-4).

The p38 mitogen-activated protein kinase pathway regulates interleukin-6 synthesis in response to tumor necrosis factor in osteoblasts

The induction of interleukin-6 (IL-6), using a proinflammatory cytokine (tumor necrosis factor-alpha), was studied in a human osteoblast cell line (MG-63) in relation to p38 mitogen-activated protein kinase (MAPK) and nuclear factor (NF)-kappaB transcription factor. When added to MG-63 cells, tumor necrosis factor-alpha (TNF-alpha) had a stimulatory effect on the production of IL-6, and this elevation was significantly reduced by SB203580, a specific p38 MAPK inhibitor. In addition, the stimulation of IL-6 release was also reduced by pyrrolidine dithiocarbamate (PDTC) or NF-kappaB SN50, which has been reported to be a potent NF-kappaB inhibitor. Both the NF-kappaB inhibitors in the presence of SB203580 had a more inhibitory effect on IL-6 release. In this study, TNF-alpha stimulated NF-kappaB binding affinity as well as p38 MAP kinase activation, leading to the release of IL-6. However, the specific inhibitor of p38 MAPK, SB203580, had no effect on TNF-alpha-induced NF-kappaB activation and both NF-kappaB inhibitors failed to reduce the p38 MAPK activation in the TNF-alpha-stimulated osteoblasts. In addition, inhibition of p38 MAPK partially, but significantly, impaired TNF-alpha-regulated release of osteocalcin, an important differentiation marker in osteoblasts. These results strongly suggest that both p38 MAPK and NF-kappaB are required in TNF-alpha-induced IL-6 synthesis and that these two TNF-alpha-activated pathways can be primarily dissociated. Furthermore, p38 MAPK may play a significant role in differentiation in MG-63 cells.

Protein kinase C suppresses spontaneous, transient, outwards K+ currents through modulation of the Na/Ca exchanger in guinea-pig gastric myocytes

The effect of protein kinase C (PKC) on the Ca2+-activated K+ current (IK,Ca) in guinea-pig gastric myocytes was studied using the whole-cell voltage-clamp technique. At a holding potential of 0 mV, IK,Ca, recorded as spontaneous, transient, outwards currents (STOCs), was markedly inhibited, both in mean amplitude (54 +/- 5%) and frequency (60 +/- 8%) by 1 microM phorbol 12, 13 dibutyrate (PDBu, n = 6). These effects were antagonized by pretreatment with 10 nM bisindolylmaleimide I (n = 5), a selective inhibitor of PKC. The possibility that the inhibition of STOCs was due to direct channel inhibition by PKC was addressed using inside-out or open-cell-attached patch-clamp techniques, the latter established using beta-escin. PDBu did not alter the conductance or open probability of the KCa channel in any mode, suggesting that PKC does not inhibit the KCa channel directly. To study the involvement of the Na/Ca exchanger in the inhibition of STOCs by PDBu, its operation was prevented by replacing Na+ in the internal solution by tris(hydroxymethyl)aminomethane (TRIS) and external Na+ by equimolar K+ and Ca2+-activated inwards K+ currents recorded at a holding potential of 0 mV. Neither the mean amplitude (96 +/- 8%) nor the frequency of these currents was inhibited significantly by 1 microM PDBu (n = 5). Like PDBu, 5 microM 2-(2-[4-(4-nitrobenzyloxy)phenyl]ethyl) isothiourea methanesulphonate (KB-R7943), a selective inhibitor of the reverse mode Na/Ca exchanger, also inhibited the mean amplitude (45 +/- 6%) and frequency (26 +/- 2%) of STOCs at the holding potential of 0 mV (n=6). The results suggest that the suppression of STOCs by PKC is mediated by inhibition of the Na/Ca exchanger.

Experimental salivary pellicles on the surface of orthodontic materials

The purpose of this study was to define the composition of salivary pellicles that form on the surfaces of orthodontic materials and to further investigate whether qualitative differences exist between the composition of adsorbed salivary pellicles that form on 3 different orthodontic materials: stainless steel bracket metal, elastomeric ligature ring, and bracket bonding resin. Experimental pellicles were formed by incubating these materials in fresh human parotid or submandibular-sublingual saliva for 2 hours. Pellicles were extracted with sodium dodecyl sulfate buffer and lyophilized. They were then subjected to sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunoblotting to identify the adsorbed salivary components. Remarkable differences in the profiles of pellicle components were found, dependent on the type of orthodontic materials. The pellicle components on the bracket metal were almost the same as those found on the elastomeric ligature ring. Salivary protein adsorption patterns to bonding resin showed different features. Distinct differences were also found between the surface-binding affinities of the same salivary proteins from different glandular salivas. These results may be explained on the basis that binding sites for specific proteins on the surfaces of the materials are covered by molecules of submandibular-sublingual saliva, probably mucins. The results of this study provide valuable information concerning initial bacterial adhesion to the surfaces of orthodontic materials, as well as information that could be used in the development of orthodontic materials with enhanced surface properties.

Intestinal metastases from gastric adenocarcinoma: helical CT findings

PURPOSE

The purpose of this work was to describe the helical CT findings of intestinal metastasis from gastric adenocarcinoma.

METHOD

Twenty-three patients with intestinal metastasis from gastric adenocarcinoma found at helical CT were included. CT findings and clinical and pathologic data were reviewed.

RESULTS

The most common characteristic finding was target-like concentric bowel wall thickening (thick inner high-outer low, n = 18) involving multiple long segments with progressive thickening of the enhancing inner layer. Fifteen cases (65%) involved multiple sites, and the ascending colon (n = 12) and rectum (n = 11) were the two most common sites. Peritoneal carcinomatosis (n = 15, 65%) and bowel obstruction (n = 14, 61%) were common associated findings. Regarding the primary lesion, the majority was linitis plastica (n = 16) and poorly differentiated adenocarcinoma with or without signet-ring cell differentiation (n = 14).

CONCLUSION

Intestinal metastasis from gastric adenocarcinoma, especially of the linitis plastica type, most commonly showed target-like long segmental wall thickening with a characteristically thick inner enhancing layer on helical CT.

Prophylactic efficacy of a new gentamicin-releasing urethral catheter in short-term catheterized rabbits

OBJECTIVE

To describe an indwelling urethral catheter coated with gentamicin sulphate on the inner and outer surface of the catheter, and to evaluate the efficacy and safety of this catheter in preventing catheter-associated infections in rabbits. Materials and methods Sixty rabbits were divided equally into control and experimental groups which were then subdivided equally according to the duration of catheterization (1, 3 and 5 days). Silicone-treated latex catheters were used in the control group and gentamicin-releasing catheters in the experimental group. Urine samples and surface swabs from the catheter were cultured for bacteriological assessment, and the catheter surface examined by scanning electron microscopy to structurally analyse the biofilms.

RESULTS

The gentamicin-releasing catheter reduced the incidence of bacteriuria (defined as > or = 100 c.f.u./mL) after both 3 and 5 days of catheterization (eight and 10 rabbits, respectively, for the control catheter, vs two and four rabbits for the gentamicin-releasing catheter, P < 0.05). The surfaces of the gentamicin-releasing catheter were colonized less often than those of the control catheter after both 3 and 5 days (eight and 10, respectively, for the control, vs one and four for the gentamicin-releasing catheter, P < 0.05). Scanning electron microscopy showed the formation of bacterial biofilm throughout the 3-day and 5-day control catheters, but deterioration of the bacterial biofilm was visible on the surface of the gentamicin-releasing catheters.

CONCLUSION

This new gentamicin-releasing catheter produced an antibacterial barrier which inhibited catheter-associated urinary tract infection with no toxicity for at least 5 days. These in vivo studies suggest that this new catheter may be useful for controlling infection, with systemic and local safety, in patients undergoing short-term indwelling urethral catheterization.

Subcellular redistribution of protein kinase C isozymes is associated with rat liver cirrhotic changes induced by carbon tetrachloride or thioacetamide

BACKGROUND AND AIMS

Protein kinase C (PKC) plays a key role in the alteration of signal transduction in the liver, which may contribute to the development of liver cirrhosis. The aim of the present study was to examine the subcellular redistribution of PKC isozymes in rat liver cirrhosis, which is induced by two different cirrhotic chemical agents, carbon tetrachloride (CCl4) and thioacetamide (TAA).

METHODS AND RESULTS

Thioacetamide and CCl4 were administered to rats for 8 and 30 weeks, respectively before rats were killed and autopsies performed at 9, 20 and 30 weeks later. The TAA induced a fibrotic pattern in the liver that differed from that produced by CCl4, notably in the formation of fibrous connective tissue and the proliferation of bile ductule cells. Cholangiofibrosis and clear-cell foci were also observed in TAA-treated rats at 30 weeks. Histological examination revealed that severe cirrhotic changes were present 9 weeks after the commencement of CCl4 treatment and 30 weeks after TAA treatment.

DISCUSSION

When the subcellular redistribution of PKC isozymes (PKCalpha, -beta1, -delta, and -epsilon) was examined, all the PKC isozymes in CCl4-treated rats were found to be translocated to the membrane fraction, which may mean PKC activation, and then downregulated by proteolytic degradation after 9 weeks of treatment, which coincided with peak cirrhotic changes. All rats treated with CCl4 recovered to the control level after 20 weeks of treatment. In the case of TAA-treated rats, PKC isozymes were translocated to the particulate fraction of the liver after 9 weeks of treatment and this persisted in most of the rats for the duration of the experiment.

CONCLUSIONS

From these results, it would appear that PKC translocation preceded morphologic changes, and that an altered subcellular distribution of the PKC isozyme may be associated with the response to liver damage and carcinogenesis.

Expression patterns of cell cycle-related proteins in a rat cirrhotic model induced by CCl4 or thioacetamide

To analyze the aberrant expression of cell cycle-related proteins and their biological significance in relation to cirrhosis, we compared the cirrhotic patterns induced by two different types of cirrhotic agents, CCl4 and thioacetamide (TAA) in rats. CCl4 or TAA treatment was given to rats for 8 or 30 weeks, respectively, and the livers were removed at 9, 20, and 30 weeks after the experiment began. The TAA-induced fibrotic pattern was different from the CCl4-induced one, in terms of the formation of fibrous connective tissue and the proliferation of bile ductule cells. Cholangiofibrosis and clear cell foci were also observed in TAA-treated rats at 30 weeks. Histological examination revealed severe cirrhotic changes at 9 weeks in CCl4-treated rats and at 30 weeks in TAA-treated rats. Immunoblotting for cyclin D1, E, A, B, and proliferating cell nuclear antigen (PCNA) and their counterpart protein kinases (CDK2, 4, and CDC2) showed significant overexpression in rats with severely cirrhotic livers. The p53 tumor suppressor protein increased dramatically in the CCl4-treated group, while it was not detected in the livers of TAA-treated rats. Upregulation of p21WAF1, a CDK inhibitory protein, was detected in TAA-treated rats, but not in CCl4-treated rats. Immunohistochemical data for cyclin D1, E, and PCNA were well correlated with immunoblotting data; these proteins were increased in hepatocytes surrounding the cirrhotic lesions, suggesting that hepatocyte regeneration is correlated with cell cycle-related protein expression in cirrhotic liver. In the TAA-treated rats, the expression of these proteins was increased both in hepatocytes and in ductule cells. Our data suggest that liver cirrhosis induced by CCl4 or TAA is associated with alterations in cell cycle-related proteins, and that the expression of these proteins is responsible for hepatocyte regeneration in the damaged liver and may be involved in liver carcinogenesis.

Perfusion MR imaging in gliomas: comparison with histologic tumor grade

OBJECTIVE

To determine the usefulness of perfusion MR imaging in assessing the histologic grade of cerebral gliomas.

MATERIALS AND METHODS

In order to determine relative cerebral blood volume (rCBV), 22 patients with pathologically proven gliomas (9 glioblastomas, 9 anaplastic gliomas and 4 low-grade gliomas) underwent dynamic contrast-enhanced T2*-weighted and conventional T1- and T2-weighted imaging. rCBV maps were obtained by fitting a gamma-variate function to the contrast material concentration versus time curve. rCBV ratios between tumor and normal white matter (maximum rCBV of tumor / rCBV of contralateral white matter) were calculated and compared between glioblastomas, anaplastic gliomas and low-grade gliomas.

RESULTS

Mean rCBV ratios were 4.90 degrees +/- 1.01 for glioblastomas, 3.97 degrees +/- 0.56 for anaplastic gliomas and 1.75 degrees +/-1.51 for low-grade gliomas, and were thus significantly different; p <.05 between glioblastomas and anaplastic gliomas, p <.05 between anaplastic gliomas and low-grade gliomas, p <.01 between glioblastomas and low-grade gliomas. The rCBV ratio cutoff value which permitted discrimination between high-grade (glioblastomas and anaplastic gliomas) and low-grade gliomas was 2.60, and the sensitivity and specificity of this value were 100% and 75%, respectively.

CONCLUSION

Perfusion MR imaging is a useful and reliable technique for estimating the histologic grade of gliomas.