Prevention of gentamicin induced ototoxicity by trimetazidine in animal model

OBJECTIVE

To show the efficacy of intra-peritoneally administered trimetazidine to prevent gentamicin ototoxicity, which is still an important cause of profound deafness among children in different parts of the world.

METHODS

Two groups of Swiss albino mice received daily intra-muscular injections of gentamicin for 30 days. One of the groups received trimetazidine intra peritoneally in addition to the gentamicin. Auditory thresholds of the animals were measured by evoked brain stem response at the beginning and the end of the study. Results were compared to the results of the control group, which received intra peritoneal saline injections.

RESULTS

Both groups receiving gentamicin injections had significant auditory threshold shifts, but in the group receiving additional trimetazidine, the threshold shift was not statistically significant when compared to control group. Threshold shift in gentamicin group significantly differed from that of the control group (p=0.0001) and gentamicin+trimetazidine group (p=0.0001), on the other hand there was no statistically significant difference between control group and trimetazidine+gentamicin group (p=0.102).

CONCLUSION

Gentamicin ototoxicity can be prevented by intra peritoneal trimetazidine injections in animal model. This treatment modality may be a mode of protection from gentamicin ototoxicity in children.

The repair of cerebrospinal fluid rhinorrhea: comparison of histopathologic findings with cadaveric human temporal fascia, dura mater, and autologous fascia in a rabbit model

OBJECTIVES

To evaluate the repair of cerebrospinal fluid rhinorrhea through the transnasal approach, we investigated histopathologic findings of grafting with human temporalis fascia and dura mater in a rabbit model.

DESIGN AND METHODS

Thirty-two rabbits were assigned to three groups according to the graft material to be used: human dura mater, human temporalis fascia, and autologous muscle fascia (control group). The repair of the surgically induced bony opening was performed via the transnasal approach. To evaluate healing process histopathologically, decapitation was performed at the end of 1, 2, 3, and 4 weeks in the control group; 1, 2, 3, 4, 32 and 40 weeks in the dura mater group; 4, 32 and 40 weeks in the temporalis fascia group.

RESULTS

Macroscopically, adhesions to the cerebral cortex were not observed with any of the grafts. Histopathologically, complete healing occurred in four weeks in the control group. Healing took longer in both cadaveric graft groups, in which formation of giant cells was the most prominent feature at the end of four weeks, suggesting a late rejection. Nevertheless, these cells disappeared and complete resolution was observed at the end of 32 and 40 weeks. Despite prolonged healing, no adverse clinical effects were observed.

CONCLUSION

This experimental model showed that human temporalis fascia can be used instead of dura mater in the repair of cerebrospinal fluid rhinorrhea.

Hamartoma of the larynx: an unusual cause of upper airway obstruction

Hamartomas are rare lesions in the larynx. Both clinical and histopathological findings may be misleading to both the physician and the pathologist in terms of diagnosis. A 51-year-old female with the complaints of nonproductive cough and severe dyspnea lasting for a year was found to have a subglottic, submucosal mass almost totally obstructing the laryngeal lumen. Excisional biopsy was performed under suspensory direct laryngoscopy. Histopathological examination showed numerous, large, distended blood vessels, some of which had prominent thickened walls and mature adipose tissue beneath the surface epithelium. The final diagnosis was hamartoma, but we discussed its validity and other possible identifications in accordance with the literature.

Expression of MUC1 and MUC2 mucins in gastric carcinomas: their relationship with clinicopathologic parameters and prognosis

The aim of this study was to investigate the relationship between MUC1 and MUC2 mucin expressions and clinicopathologic variables in gastric carcinomas with regard to survival times. MUC1 and MUC2 expressions were revealed immunohistochemically in 143 gastric carcinomas. Of these 143 patients, follow-up data were available for 45 (median survival time of 30 months, ranging from 2 to 80 months). MUC1 was detected in 82 (58%), and MUC2 in 60 (42%) out of 143 cases. Papillary adenocarcinomas showed significantly higher MUC1 and MUC2 immunoreactivity than did signet-ring cell and mucinous tumors (p = 0.045 and p = 0.01, respectively). MUC1 was highly positive in intestinal-type carcinomas (p = 0.006), whereas intestinal and diffuse carcinomas did not differ in MUC2 expression. There was a positive correlation between tumor differentiation and MUC1 expression. However, no correlation was found between MUC1 and MUC2 expressions and angiolymphatic invasion. According to the TNM classification, stage 1A tumors have significantly lower rates of MUC1 reactivity compared to higher stages (p = 0.04). The patients with gastric carcinomas expressing MUC1 showed significantly poorer survival than those without MUC1 expression (p = 0.04). The present study suggests that MUC1 expression be a useful prognostic factor for predicting the outcome of gastric carcinoma patients, whereas the role of MUC2 expression is still unclear.

Effects of topical vitamin E on corneal superoxide dismutase, glutathione peroxidase activities and polymorphonuclear leucocyte infiltration after photorefractive keratectomy

PURPOSE

Photorefractive keratectomy (PRK) induces free radical formation and polymorphonuclear (PMN) cell infiltration in the cornea. Vitamin E is a free radical scavenger and protects the cells from reactive oxygen species. We investigated the effects of topical vitamin E on corneal PMN cell infiltration and corneal antioxidant enzyme activities after PRK.

METHODS

We studied four groups, each consisting of seven eyes. Group 1 were control eyes. In group 2 the corneal epithelium was removed by a blunt spatula (epithelial scrape). In group 3, corneal photoablation (59 micro m, 5 dioptres) was performed after epithelial removal (traditional PRK). In group 4 we tested the effects of topical Vitamin E after traditional PRK. Corneal tissues were removed and studied with enzymatic analysis (measurement of corneal superoxide dismutase and glutathione peroxidase activities) and histologically.

RESULTS

Stromal PMN leucocyte counts were significantly higher after mechanical epithelial removal and traditional PRK (p < 0.05). Corneal superoxide dismutase and glutathione peroxidase activities decreased significantly after mechanical epithelial removal and traditional PRK (p < 0.05). In group 4, treated with vitamin E, corneal superoxide dismutase activity did not differ significantly from that in the medically non-treated groups, nor did corneal PMN cell infiltration after traditional PRK. The reduction of corneal glutathione peroxidase activity after PRK was reduced significantly after topical vitamin E treatment.

CONCLUSIONS

Topical vitamin E treatment may be useful for reducing the harmful effects of reactive oxygen radical after epithelial scraping and PRK in that it increases corneal glutathione peroxidase activity.

Prognostic importance of tumor angiogenesis in breast carcinoma with adjuvant chemotherapy

Tumor angiogenesis is believed to be related to prognostic factors involved in tumor development and metastasis. Using immunohistochemical methods, we evaluated tumor angiogenesis in 42 early invasive breast cancer patients (T1-2, NO-1-2, M0). Four patients received tamoxifen, 25 patients received CAF or CA, and 15 patients received CMF as adjuvant therapy. The median follow-up was 47 (range 24-119) months. Ten patients (43.5%) in the node-positive group and 2 patients (10.5%) in the node-negative group relapsed (p = 0.019). The mean microvessel count (MVC) was 60.3 3.05 per 200x field (range: 16-95). MVCs of postmenopausal and premenopausal patients were 50.13 +/- 5.74 and 68.64 +/- 4.11, respectively, in the axillary lymph node (ALN)-negative patient group (p = 0.04). Staining was moderate to strong in 13 (68%) ALN-negative and in 17 (74%) ALN-positive patients (p > 0.05), and was also moderate to strong in 82% of premenopausal patients and in 50% of postmenopausal patients (p = 0.037). There was no significant relationship between angiogenesis and p53, nor was angiogenesis significantly associated with the patient ER status and tumor size. No significant correlations were found between OS/DFS and Factor VIII staining or p53 (log rank test, p > 0.05). Of all ALN-negative patients with increased angiogenesis, one patient of the CMF group relapsed, but no recurrence occurred in patients undergoing anthracycline-based chemotherapy (p > 0.05). On the other hand, of all ALN-positive patients with increased angiogenesis, 5/14 patients treated with anthracylcine and 2/2 CMF-treated patients relapsed (p = 0.175). Despite the statistical insignificance, anthracycline-based adjuvant chemotherapy appears to be more effective than CMF as regards relapse prevention particularly in early ALN-positive breast cancer patients with increased angiogenesis. Additional studies are necessary to demonstrate the clinical importance of angiogenesis.

The protective effect of taurine pretreatment on carbon tetrachloride-induced hepatic damage--a light and electron microscopic study

The results regarding taurine pretreatment on CCl(4)-induced hepatic injury are controversial. To assess the therapeutic efficacy of taurine on rat liver injury, hepatic malondialdehyde, glutathione, and hydroxyproline levels together with morphologic alterations in the liver following CCl(4) administration were investigated. The rats were divided into three groups. Taurine-treated animals received 15 ml/kg/day of a 5% taurine solution by a gastric tube for 5 days before administering CCl(4) (2 ml/kg, intraperitoneally, in a single dose). CCl(4)-treated rats received the same amount of saline solution. Control animals received no treatment. The increase of hepatic malondialdehyde formation in the CCl(4)-treated group was partially prevented by taurine pretreatment, but taurine had no significant effect on the glutathione and hydroxyproline content in the CCl(4)-treated rats. Taurine pretreatment induced a marked beneficial effect regarding the prevention of hepatocellular necrosis and atrophy as demonstrated morphologically. In conclusion, these results suggest that taurine pretreatment might not significantly change the biochemical parameters, but prevents the morphologic damage caused by CCl(4) in the early stages.

Hepatic failure due to CD3+ plasma cell infiltration of the liver in multiple myeloma

We present a case of multiple myeloma who died of liver failure 7.5 months after initial diagnosis. Postmortem liver biopsy revealed diffuse CD3-expressing plasma cell infiltration and eosinophilic amorphous material deposition which was considered as light chain deposits. T cell receptor-gamma rearrangement was not detected in liver biopsy sections using the polymerase chain reaction despite CD3 positivity. To our knowledge, this is the first report of CD3-expressing plasma cell infiltration in tissue sections. The discordance between the phenotype and the genotype suggests a partial activation of genes encoding the T cell antigens by the transforming event. We also concluded that CD3 positivity was associated with short survival, which is consistent with previous data.

Effect of mechanical vs dilute ethanol epithelial removal on keratocyte apoptosis and polymorphonuclear leukocyte migration

PURPOSE

To investigate keratocyte apoptosis and polymorphonuclear (PMN) cell infiltration to the corneal stroma after mechanical epithelial scraping and chemical de-epithelialization with 18% ethanol solution.

METHODS

Twelve New Zealand Albino rabbits (24 eyes) were randomly divided into three groups. Group A was the control group with no epithelial removal. Group B underwent a 7.5-mm mechanical epithelial removal with a blunt spatula. Group C underwent 7.5-mm chemical de-epithelialization with 18% ethanol-balanced salt solution. Corneas were stained with terminal deoxyribonucleotidyl transferase-mediated dUTP-digoxigenin nick-end labeling (TUNEL) assay after 24 h. Only nuclear staining in keratocytes was counted. Polymorphonuclear (PMN) leukocyte densities were also assessed by light microscopy.

RESULTS

Mechanical de-epithelialization (group B) and chemical de-epithelialization with 18% ethanol (group C) showed no difference in keratocyte apoptosis compared with the control group. There was also no difference between groups B and C. Group B showed no difference in PMN leukocyte counts compared with the control group. But the number of PMN leukocytes observed in group C was significantly higher than those encountered in the corneas of the control group (P < 0.05) and group B (P < 0.05).

CONCLUSIONS

Dilute alcohol induces more PMN cell infiltration when compared with mechanical de-epithelialization although there is no difference in the apoptosis rates.

Keratocyte apoptosis and corneal antioxidant enzyme activities after refractive corneal surgery

PURPOSE

Refractive corneal surgery induces keratocyte apoptosis and generates reactive oxygen radicals (ROS) in the cornea. The purpose of the present study is to evaluate the correlation between keratocyte apoptosis and corneal antioxidant enzyme activities after different refractive surgical procedures in rabbits.

METHODS

Rabbits were divided into six groups. All groups were compared with the control group (Group 1), after epithelial scraping (Group 2), epithelial scrape and photorefractive keratectomy (PRK) (traditional PRK: Group 3), transepithelial PRK (Group 4), creation of a corneal flap with microkeratome (Group 5) and laser-assisted in situ keratomileusis (LASIK, Group 6). Terminal deoxyribonucleotidyl transferase-mediated dUTP-digoxigenin nick-end labelling assay (to detect DNA fragmentation in situ) and light microscopy were used to detect apoptosis in rabbit eyes. Glutathione peroxidase (Gpx) and superoxide dismutase (SOD) activities of the corneal tissues were measured with spectrophotometric methods.

RESULTS

Corneal Gpx and SOD activities decreased significantly in all groups when compared with the control group (P<0.05) and groups 2, 3 and 6 showed a significantly higher amount of keratocyte apoptosis (P<0.05). Not only a negative correlation was observed between corneal SOD activity and keratocyte apoptosis (cc: -0.3648) but Gpx activity also showed negative correlation with keratocyte apoptosis (cc: -0.3587).

CONCLUSION

The present study illustrates the negative correlation between keratocyte apoptosis and corneal antioxidant enzyme activities. This finding suggests that ROS may be partly responsible for keratocyte apoptosis after refractive surgery.

Bcl-2 and LMP1 expression in nasopharyngeal carcinomas

In vitro studies of B-cells immortalized by Epstein-Barr Virus (EBV) have shown that B-cell leukemia/lymphoma-2 (bcl-2) protein expression is upregulated by the EBV-latency-associated antigen, latent membrane protein 1 (LMP1). The same phenomenon has also been observed in epithelial cells in vitro. However, such correlation between these 2 markers has not been shown in nasopharyngeal carcinoma (NPC), in which EBV infection is a well-known etiologic factor. This retrospective study examined 35 cases of undifferentiated NPC to answer the question of whether LMP1 and/or bcl-2 presence can be used as biomarkers at treatment response, as well as to see the relationship between bcl-2 and LMP in NPC. Of the 35 patients, 26 (74.3%) were bcl-2, and 10 (28.6%) were LMP1-positive. Although a significant correlation was observed between bcl-2 and LMP1 staining (P =.003), it appeared that bcl-2 expression could be independent of LMP1. Statistical analysis showed that cervical lymph node metastasis (P =.04) and cranial nerve involvement (P =.03) are the only variables that significantly affect patient survival. At this time, bcl-2 and LMP1 presence are not significant indicators of outcome; however, although they are not directly related to survival, expression of both bcl-2 and LMP1 was strongly correlated with cervical lymph node metastasis, which is a potent predictor of patient survival.

Association between the severity of heart failure and the susceptibility of myocytes to apoptosis in patients with idiopathic dilated cardiomyopathy

BACKGROUND

Bcl-2 proto-oncogene, an inhibitor of apoptosis and Bax proto-oncogene, an inducer of apoptosis play critical roles in the molecular circuit controlling apoptosis in cardiac muscle. The ratio of Bax to Bcl-2 proto-oncogene determines survival or death after an apoptotic stimulus. We speculated that susceptibility of myocytes to apoptosis determined as the Bax/Bcl-2 ratio might vary with the severity of heart failure.

METHODS AND RESULTS

We studied immunohistochemically 108 endomyocardial biopsy specimens from 30 patients with idiopathic dilated cardiomyopathy (mild heart failure, n=14; moderate or severe heart failure, n=16) with the use of Bcl-2 and Bax monoclonal antibodies. The expression of each protein was determined semiquantitatively as the fraction of myocytes labeled with specific monoclonal antibodies using a digital morphometric analysis system. Patients with mild heart failure showed significantly increased Bax/Bcl-2 ratio than the patients with advanced heart failure (1.59+/-1.26 vs. 0.34+/-0.43, P=0.002). The expression of Bcl-2 was found to be independent of the severity of heart failure whereas the expression of Bax was significantly higher in patients with mild heart failure compared to the patients with moderate or severe heart failure (52.1+/-29.3 vs. 21.6+/-22.4%, P=0.005). Additionally, Bax/Bac-2 ratio was inversely correlated with the mitral E-interventricular septum distance, left ventricular end-systolic and end-diastolic diameter.

CONCLUSION

The susceptibility of myocytes to apoptosis is significantly increased in the early phase of heart failure but it decreases with worsening of the disease due to depressed expression of Bax onco-protein. Increased myocyte susceptibility to apoptosis may have a role in the transition from mild heart failure to severe in patients with idiopathic dilated cardiomyopathy.

Effects of topical vitamin E on keratocyte apoptosis after traditional photorefractive keratectomy

PURPOSE

To evaluate the keratocyte apoptosis and effects of topical vitamin E on keratocyte apoptosis after photorefractive surgery.

METHODS

Rabbits were divided into 7 groups, and all groups were compared with controls after epithelial scraping, epithelial scrape and photorefractive keratectomy (PRK) (traditional PRK), transepithelial PRK, production of a corneal flap with microkeratome and laser-assisted in situ keratomileusis (LASIK). The effects of topical Vitamin E treatment were investigated in the traditional PRK group. The terminal deoxyribonucleotidyl transferase-mediated dUTP-digoxigenin nick-end labelling assay (to detect DNA fragmentation in situ) and light microscopy have been used to detect apoptosis in rabbit cornea.

RESULTS

Transepithelial PRK induced minimal keratocyte apoptosis, less than in all other refractive surgical procedures. The greatest amount of keratocyte apoptosis was observed after traditional PRK (p = 0.001), therefore we tested the effects of topical vitamin E in this group. The number of apoptotic keratocytes significantly reduced after vitamin E therapy (p < 0.005).

CONCLUSION

Keratocytes undergo apoptosis after refractive surgery in response to mechanical epithelial removal, preparing of corneal flap and excimer laser stromal photoablation. The topical application of vitamin E immediately after surgery can prevent keratocyte apoptosis, and this result suggests that free radicals may be partly responsible for keratocyte apoptosis after excimer laser keratectomy.

Investigation of the ototoxic effects of interferon alpha2A on the mouse cochlea

This prospective randomized study investigates the possible toxic effects of interferon (IFN) alpha2A on the mouse cochlea. Thirty-six albino Swiss mice that were randomly assigned to 3 groups underwent baseline auditory brain stem response testing bilaterally to objectively assess baseline hearing levels. The first group received a single dose of 50,000 units, and the second group received 100,000 units of IFN-alpha2A intraperitoneally, whereas the third group was given no medication. Repeat auditory brain stem response testing revealed a significant rise in mean baseline peak equivalent sound pressure level thresholds in the groups that received IFN (P < 0.001). Histologically, the cochleae of mice that received IFN had a decreased number of fibroblasts in the spiral limbus, as well as prominent cytoplasmic vacuolation of these cells, compared with control animals. Loss of hair cells was not observed. It is possible that reversible biochemical and metabolic changes in the cochlea, rather than morphologic abnormalities, manifest IFN ototoxicity.

Expression of Bcl-2 and c-ErbB-2 in colorectal neoplasia

Several studies have been demonstrated the value of c-ErbB-2 and Bcl-2 in predicting the biological behaviour of tumors. The aim of this study was to investigate Bcl-2 and c-ErbB-2 expression in colorectal carcinomas and the correlation between their presence and other clinicopathologic parameters. Eighty-six colorectal carcinomas and 17 adenomas were stained with Bcl-2 and c-ErbB-2 immunohistochemically. Staining patterns were assessed semi-quantitatively and correlated with tumor size, Duke s classification, tumor differentiation, mucinous characteristic and anatomic locations. We detected Bcl-2 expression in 10 of 17 adenomas (58.8 %) and 31 of 86 carcinomas (36.04 %). Positive staining in normal mucosa was observed only in the compartment of cryptic cells. However neither the difference in the rates of Bcl-2 positivity in adenoma and carcinoma groups, nor the correlation with other mentioned clinicopathological parameters, were found statistically significant. Bcl-2 expression was found to be significantly high in mucinous carcinomas. Expression of c-ErbB-2 was observed in 12 of 86 (13.95 %) carcinomas. It was not detected in adenomas and normal mucosa. Although the incidence of c-ErbB-2 in nonmucinous carcinoma was higher than that of mucinous carcinoma, this was not significant. In addition we were unable to show any significant relation between c-ErbB-2 expression and other clinicopathologic features. Our result suggest that c-ErbB-2 protein expression in colorectal carcinomas, is not very frequent event. There is no correlation between c-ErbB-2 expression and malignant potential of colorectal carcinomas. Higher expressions of Bcl-2 in adenomas than carcinomas suggest us a possible role of Bcl-2 in early carcinogenesis of colon. However since we were unable to find any significant correlation between Bcl-2 expression and other parameters the impact of this gene on biological behavior is still unclear for us.

Differences in liver pathology and clinical outcome between two patients with hepatitis B virus and graft versus host disease

Our two patients undergoing allogeneic bone marrow transplantation (AlloBMT) had both Hepatitis B virus (HBV) and graft-versus-host disease (GVHD). In the first patient, liver enzymes elevated three months after AlloBMT, and GVHD was diagnosed. Two weeks after the diagnosis of GVHD, HBsAg appeared in his serum. At that time, liver biopsy was not able to discriminate two disorders, but his sequential liver biopsies disclosed GVHD. Despite the patient was treated with cyclosporin A (CsA), he died for chronic GVHD. In contrast to the first patient, the second patient had HBsAg prior to GVHD. His liver enzymes deterioration was detected in the first month after AlloBMT, and reached the highest level in the third month while withdrawing CsA. In the fifth month he developed scleradermatous skin changes, and skin biopsy revealed chronic GVHD, whereas concurrent liver biopsy revealed chronic active hepatitis. This observation showed that immunosuppressive conditions such as GVHD or its prophylaxis may affect the appearance of liver pathology caused by HBV, which depends on the time of GVHD development, and the duration and depth of GVHD prophylaxis.

Hematopoietic stem cell transplantation from non-replicative hepatitis B virus carriers is safe

BACKGROUND/AIMS

Hepatitis B virus can cause serious problems in individuals undergoing organ transplantation. The aim of this study was to evaluate the hepatic events among HBs-Ag positive recipients and HBs-Ag negative recipients who received products from hepatitis B virus carriers.

METHODS

A total of 151 patients received an allogeneic hematopoietic stem cell transplantation at the Department of Hematology-Oncology, University of Ankara, between June 1989 and June 1998. Among these, eight HBs-Ag positive and four HBs-Ag negative recipients received a product from a hepatitis B virus positive donor. The median follow-up period for these 12 patients was 13.2 months.

RESULTS

Three of the eight HBs-Ag positive recipients died (one from hepatic failure); of the remainder, two are HBs-Ag negative, two HBs-Ag positive with normal liver injury tests and one HBs-Ag positive with elevated ALT levels. Of the four HBs-Ag negative recipients who received stem cells from a hepatitis B positive donor, two died; none of the patients in this group became HBs-Ag positive after transplantation.

CONCLUSION

Hepatitis B virus infection is a common problem in patients being considered for allogeneic hematopoetic stem cell transplantation, especially in areas where hepatitis B virus infection is endemic. We believe that the presence of HBs-Ag positivity is not an absolute contraindication for allogeneic hematopoetic stem cell transplantation unless the hepatitis B virus is in a replication phase.

Expression of c-erbB-2 oncoprotein in gastric carcinoma: correlation with histopathologic characteristics and analysis of Ki-67

Amplification and overexpression of the c-erbB-2 gene has been demonstrated in several tumors and thought to be important determinants of biologic behaviors of carcinomas. In this study, correlation between c-erbB-2 expression und histopathologic parameters, including proliferative activity of gastric carcinomas was evaluated. Paraffin-embedded tissue sections from 62 patients who underwent curative resection of gastric carcinoma were analyzed immunohistochemically for the expression of c-erbB-2 and Ki-67. Strong membrane staining for c-erbB-2 was detected in 11 of 62 gastric carcinomas (17,7%) and no positive reaction was evident in noncancerous tissue. The incidence of c-erbB-2 positivity in intestinal type carcinomas (24,3%) was higher than that of diffuse type carcinomas (4,76%). Positive staining for c-erbB-2 was present in one of the 9 (11,1%) early gastric carcinomas and 10 of 53 (18, 8%) advanced gastric carcinomas. However, no statistically significant relationships were found between c-erbB-2 expression and histopathologic type, depth on invasion, the tumor size or lymph node metastases. Among the metastatic lymph nodes, 3 were positively stained with c-erbB-2 whereas the primary tumors of two cases had been found to be negative. Additionally, no correlation was found between c-erbB-2 reactivity and proliferative activity of carcinoma cells. The results suggest that expression of c-erbB-2 protein may occur selectively in intestinal type of gastric carcinomas. However, c-erbB-2 expression is not a reliable marker of malignant potential in gastric carcinomas.

The protective effect of Ginkgo biloba extract on CCl4-induced hepatic damage

The aim of this study was to evaluate the protective effect of Ginkgo biloba extract on CCl4-induced hepatic damage in rats. Hepatic malondialdehyde, glutathione and hydroxyproline levels and histopathologic alterations in liver specimens were assessed. 200 mg/kg/day Ginkgo biloba extract were given orally to the animals for 10 days, then a single dose of 2 ml/kg b.w. carbon tetrachloride was, administered intraperitoneally. Ginkgo biloba extract treatment reduced hepatic malondialdehyde levels significantly (p < 0.05), but did not alter glutathione (p > 0.05) and hydroxyproline levels (p > 0.05). The light and electron microscopic findings showed that Ginkgo biloba extract limited the CCl4-induced hepatocyte necrosis and atrophy. These results suggest that this extract may protect the hepatocytes from carbon tetrachloride-induced liver injury.

P53 and proliferating cell nuclear antigen (PCNA) expression in non-tumoral liver diseases

The tumor suppressor gene p53 is known to be involved in the negative regulation of cell growth. Proliferating cell nuclear antigen (PCNA), which is a nuclear protein and a component of the DNA replication process, is also involved in growth regulation. Both have been studied as progression markers in various tumors including hepatocellular carcinoma. In the present study, the aberrant p53 protein and PCNA expressions in non-tumoral liver diseases were investigated. Using monoclonal antibodies anti-p53 (D07-DAKO) and anti-PCNA (PC10-DAKO), 149 samples were stained, including 10 normal and 10 tumoral control liver tissues. p53 Overexpression was detected in 52 specimens (35%) whereas PCNA positivity was found in 96 (64%). There were 21 different pathological entities but most of the positive samples could be grouped into four types of diseases; namely, non-specific reactive hepatitis, steatohepatitis, chronic hepatitis and cirrhosis. Statistical analyses performed on these groups revealed that p53 positivity was found to be significantly higher in steatohepatitis (P < 0.05), while PCNA positivity did not show any statistical significance. The number of samples showing both p53 and PCNA positivity was 42 but their coexistence was not found to be significant. Certain cytological alterations like nuclear pleomorphism, steatosis and cholestasis, in addition to necroinflammatory activity, were evaluated for their possible impact on p53 and/or PCNA positivity. Necroinflammatory activity in steatohepatitis and steatosis in chronic hepatitis was found to be significant for p53 positivity (P < 0.05). In contrast, nuclear pleomorphism in non-specific reactive hepatitis was found to be significant for PCNA positivity (P < 0.05).

Proliferating cell nuclear antigen immunoreactivity and the presence of P53 mutation in basaloid squamous cell carcinoma of the larynx

Basaloid squamous cell carcinoma (BSCC) is an aggressive variant of squamous cell carcinoma (SCC) that was first described in 1986. In the English literature, only 28 cases of this histopathological entity have been reported in the larynx. Proliferative features of this infrequent tumor were investigated by proliferating cell nuclear antigen immunoreactivity, and the presence of P53 mutation was also investigated in a series of 4 cases. BSCC was found to share similar features with regular SCC in terms of its proliferation rate and P53 mutation positivity, as well as biological behavior and clinical outcome.

Immunohistochemical localization of the epidermal growth factor receptor in normal mouse tissues

The levels of epidermal growth factor (EGF) receptors were investigated in normal mouse tissues. Two patterns of reactivity were recognized: strong membraneous of diffuse cytoplasmic staining. The basal epithelial cells of the skin and the collecting tubule cells of the kidney showed membraneous reactivity whereas the bronchial epithelial cells, parietal cells of the stomach and tubular cells of the kidney showed cytoplasmic reactivity predominantly with the antibody. The distribution of the epidermal growth factor receptors in different cell types and cellular compartments may implicate varying activation states of the growth factor and its interaction with a milieu available ligand.

Hepatitis B virus infection in allogeneic bone marrow transplantation

Fourty-four patients who underwent allogeneic bone marrow transplantation (alloBMT) were studied for hepatitis B virus (HBV)-related complications. The mean follow-up period was 15.3 months. Positivity for HBV surface antigen (HBsAg) was observed in 10 patients (22.7%) throughout the study. Four of the 10 patients were HBsAg carriers before alloBMT, while the remaining six became HBsAg(+) after alloBMT. During the follow-up period (from 6 months to 45 months), an elevation in serum ALT activity was observed in the four carriers when immunosuppression was reduced or withdrawn. All of the four HBsAg carriers developed hepatitis, but none of them died of liver failure due to HBV. Only one death due to GVHD and diabetic ketoacidosis was observed in this group. Two of the four carriers received marrow from anti-HBs positive donors and one of them cleared HBsAg from his serum via adoptive immunity 8 months after transplantation. The remaining six patients acquired HBV after alloBMT, but we were unable to demonstrate the source of HBV. Five of them had a moderate increase in serum ALT activity while the other patient had a normal ALT. Two patients seroconverted to anti-HBs spontaneously. Two patients died during the follow-up, one due to intracranial hemorrhage and the other due to GVHD and accompanying pulmonary infection. The rest of the study group (34 patients) remained HBsAg(-) throughout the study. Two of them had an HBsAg(+) donor, but neither developed HBV infection in their follow-up period. The acquisition rate of HBV infection was relatively low in recipients who were positive for anti-HBs compared to those who were negative for anti-HBs (8 vs 19%). Anti-HBs positivity remained for a longer period in recipients who received marrow from anti-HBs positive donors compared to those recipients who had anti-HBs negative donors (median 12 vs 3 months). We think that HBV is a frequent cause of liver dysfunction in alloBMT patients where HBV infection is endemic. Whether the disease is in the form of reactivation of HBsAg-positive recipients, or is acquired from unknown sources in recipients who never had contact with the virus, the course of the disease is not fatal. Silent serologic changes can be demonstrated if viral serologic markers are sought serially. Among them, the disappearance of serum anti-HBs may be important as it increases the risk of HBV contamination in recipients.

Correlation of nuclear p53 over-expression with clinical and histopathological features of transitional cell bladder cancer

Forty-four pathologic specimens of 39 bladder cancer patients were analyzed immunohistochemically with D07 monoclonal antibody to detect over-expression of mutant p53 gene. The findings were interpreted by correlating with patient age, sex, cigarette smoking, number and macroscopic appearance of tumour, histological tumour grade, muscular invasion, vascular invasion, necrosis and urothelial atypia or dysplasia. Mutant p53 gene was over-expressed in 8 (18.2%) specimens. Statistically significant correlation with grade, vascular invasion, necrosis and patient sex was found with p53 over-expression. Available follow-up data were insufficient to draw a conclusion about the prognostic role of p53 over-expression. Prospective studies with larger number of patients are needed to define the exact place of nuclear p53 over-expression in transitional cell bladder cancer.