Cognitive Decline and Modulation of Alzheimer's Disease-Related Genes After Inhibition of MicroRNA-101 in Mouse Hippocampal Neurons.

MicroRNAs have emerged as regulators of brain development and function. Reduction of miR-101 expression has been reported in rodent hippocampus during ageing, in the brain of Alzheimer's disease (AD) patients and in AD animal models. In this study, we investigated the behavioral and molecular consequences of inhibition of endogenous miR-101 in 4-5-month-old C57BL/6J mice, infused with lentiviral particles expressing a miR-101 sponge (pLSyn-miR-101 sponge) in the CA1 field of the hippocampus. The sponge-infected mouse model showed cognitive impairment. The pLSyn-miR-101 sponge-infected mice were unable to discriminate either a novel object location or a novel object as assessed by object place recognition (OPR) and novel object recognition (NOR) tasks, respectively. Moreover, the sponge-infected mice evaluated for contextual memory in inhibitory avoidance task showed shorter retention latency compared to control pLSyn mice. These cognitive impairment features were associated with increased hippocampal expression of relevant miR-101 target genes, amyloid precursor protein (APP), RanBP9 and Rab5 and overproduction of amyloid beta (Aß) 42 levels, the more toxic species of Aß peptide. Notably, phosphorylation-dependent AMP-activated protein kinase (AMPK) hyperactivation is associated with AD pathology and age-dependent memory decline, and we found AMPK hyperphosphorylation in the hippocampus of pLSyn-miR-101 sponge mice. This study demonstrates that mimicking age-associated loss of miR-101 in hippocampal neurons induces cognitive decline and modulation of AD-related genes in mice.

Expression of the microRNA regulators Drosha, Dicer and Ago2 in non-small cell lung carcinomas.

PURPOSE: MicroRNAs are evolutionarily conserved non-coding components of the transcriptome that can post-transcriptionally control gene expression. Altered microRNA expression has been found to be a common feature of several cancers, including lung carcinomas. The biogenesis and maturation of microRNAs is known to be mediated by the ribonucleases Drosha, Dicer and Ago2. The purpose of the present study was to investigate the expression and distribution of Drosha, Dicer and Ago2 in human non-small cell lung carcinomas (NSCLC) and to relate the respective expression patterns to clinocopatholical features. METHODS: We used five human NSCLC-derived cell lines and primary formalin-fixed paraffin-embedded tissue samples from 83 NSCLC patients. Drosha, Dicer and Ago2 mRNA and protein expression levels, and their sub-cellular distributions, were assessed using RT-PCR, Western blotting, immunofluorescence and immunohistochemistry, respectively. RESULTS: We found that Drosha, Dicer and Ago2 were expressed in all the cell lines and primary neoplastic and non-neoplastic tissue samples tested. The intensity of the immunohistochemical staining was found to be significantly lower in stage I tumors compared to normal lung tissues. Dicer expression was found to be significantly higher in stage II compared to stage I tumors, and in stage III compared to stage II and stage I tumors. CONCLUSIONS: Our results point at a role of Drosha, Dicer and Ago2 in the development of NSCLC and suggest that Dicer may be implicated in the progression of these tumors to advanced stages.

Integrin beta-3 L33P: a new insight into the pathogenesis of chronic oxaliplatin-induced peripheral neuropathy?

AIM: To assess the significance of the ITGB3 polymorphism at residue 33 (ITGB3 L33P) in the development of chronic oxaliplatin-induced peripheral neuropathy (OXLIPN). METHODS: Fifty-five patients with advanced colorectal cancer were genotyped, using allele-specific primers and sybr green in real-time PCR. Patients had received adjuvant oxaliplatin-based chemotherapy. The severity of the OXLIPN was defined by means of the clinical total neuropathy score (TNSc). Following the discontinuation of treatment, 34/55 patients (61.8%) developed OXLIPN. Grade I neurotoxicity was revealed in 13 (38.2%) patients and grade II neurotoxicity in 21 (61.8%) patients. RESULTS: Patients without OXLIPN (n = 21) were 19% homozygous for C, 33.3% were heterozygous, and 47.7% were homozygous for T. The corresponding percentages for patients developing any grade of OXLIPN (n = 34) were similar. About half of patients (46.1%) with grade I OXLIPN were heterozygotes (CT), 23.1% were CC, and 30.8% were TT. The majority of patients with grade II OXLIPN were TT (66.7%) with the remaining 33.3% being CT. The TT genotype was associated with increased severity of OXLIPN compared to the genotypes containing the C allele (P = 0.044). CONCLUSION: The ITGB3 L33P seems to be unrelated to the development of OXLIPN, but it appears to be related to its severity.

The effect of different physical activity levels on muscle fiber size and type distribution of lumbar multifidus. A biopsy study on low back pain patient groups and healthy control subjects.

AIM: Previous studies examining the multifidus fiber characteristics among low back pain (LBP) patients have not considered the variable of physical activity. The present study sought to investigate the muscle fiber size and type distribution of the lumbar multifidus muscle among LBP patient groups with different physical activity levels and healthy controls. METHODS: Sixty-four patients were assigned to one of three groups named according to the physical activity level, determined for each patient by the International Physical Activity Questionnaire. These were low (LPA), medium (MPA) and high (HPA) physical activity groups. A control group comprising of 17 healthy individuals was also recruited. Muscle biopsy samples were obtained from the multifidus muscle at the level L4-L5. RESULTS: contrast with the control group, LBP patient groups showed a significantly higher Type II fiber distribution as well as reduced diameter in both fiber types (P<0.05). The physical activity level did not have an effect on multifidus characteristics since no significant differences were observed in fiber type and diameter (P>0.05) among LPA, MPA and HPA patient groups. Various pathological conditions were detected which were more pronounced in LBP groups compared to the control (P<0.05). Males had a larger fiber diameter compared to females for both fiber types (P<0.05). CONCLUSIONS: The results showed that the level of physical activity did not affect muscle fiber size and type distribution among LBP patients groups. These findings suggest that not only inactivity but also high physical activity levels can have an adverse effect on the multifidus muscle fiber characteristics.

EGFR, HER-2 and COX-2 levels in colorectal cancer.

AIMS: Receptor tyrosine kinases epidermal growth factor receptor (EGFR) and HER-2 and cyclooxygenase-2 (COX-2) are promising molecular targets for cancer therapy and/or prevention. The aim was to evaluate EGFR, HER-2 and COX-2 mRNA and protein expression in colorectal cancer patients. METHODS AND RESULTS: EGFR, HER-2 and COX-2 protein levels were evaluated by immunohistochemistry in malignant tissue, dysplastic tissue and normal mucosa samples from 124 cases with primary colorectal carcinoma. Moreover, the corresponding mRNA levels were assessed by quantitative reverse transcriptase-polymerase chain reaction in 46 colorectal carcinomas. There was strong correlation between mRNA and protein expression for EGFR (P < 0.001), HER-2 (P < 0.004) and COX-2 (P < 0.007). EGFR levels did not correlate with stage of the disease or tumour differentiation. HER-2 and COX-2 levels increased in advanced stages and in differentiated carcinomas. Furthermore, a correlation between HER-2 and COX-2 expression was revealed in neoplastic tissue. CONCLUSIONS: EGFR as well as HER-2 and COX-2 overexpression represent important alterations that are related to the molecular pathways underpinning colorectal carcinogenesis. Further investigation is required to evaluate the impact of these markers on the management of patients with colorectal cancer.

Evidence for intestinal oxidative stress in patients with obstructive jaundice.

BACKGROUND: Obstructive jaundice results in failure of the intestinal barrier with consequent systemic endotoxemia associated with septic complications. We have recently shown that gut barrier failure in experimental obstructive jaundice is associated with high intestinal oxidative stress. This study was undertaken to investigate whether oxidative alterations occur in the intestinal mucosa of patients with obstructive jaundice. PATIENTS AND METHODS: Fifteen patients with malignant biliary obstruction and no signs of cholangitis and 15 control patients were subjected to duodenal biopsy to assess intestinal oxidative stress, estimated by lipid peroxidation (malondialdehyde - MDA) and glutathione redox state [reduced glutathione (GSH), glutathione disulphide (GSSG) and GSH/GSSG ratio]. In addition, mucosal biopsies were examined histologically and intestinal mucosal protein content was determined biochemically as an index of intestinal trophic state. RESULTS: Patients with obstructive jaundice presented high levels of intestinal oxidative stress, with significantly increased lipid peroxidation (P < 0.001). Glutathione redox state was also suggestive of high intestinal oxidative stress in jaundiced patients, indicated by significantly decreased GSH (P = 0.001) and GSH/GSSG ratio (P = 0.006) and increased GSSG (P = 0.026). Histological examination showed a mild infiltration of the lamina propria by chronic inflammatory cells in obstructive jaundice, whereas duodenal architecture remained intact and epithelial continuity was retained. Duodenal mucosa was atrophic in jaundiced patients as indicated by a significant reduction of mucosal protein content compared with controls (P = 0.001). Among oxidative stress parameters, intestinal GSH exhibited a significant positive correlation with mucosal protein content (r = 0.588, P = 0.021). CONCLUSIONS: Obstructive jaundice in humans induces intestinal oxidative stress, which may be a key factor contributing to intestinal barrier failure and the development of septic complications in this patient population.

Involvement of dysadherin and E-cadherin in the development of testicular tumours.

Testicular neoplasms are comprised of a variety of histologically different forms, and their pathogenesis has not been elucidated. Dysadherin is a recently described cell membrane glycoprotein, which has an anticell-cell adhesion function and downregulates E-cadherin. In this study, we examined immunohistochemically the expression of E-cadherin and dysadherin in 120 testicular neoplasms (37 seminomas-26 classic, five spermatocytic and six anaplastic-, 45 embryonal carcinomas, 10 mixed germ cell tumours, two yolk sac tumours, 10 mature and eight immature teratomas and eight non-Hodgkin B-cell lymphomas), clinical stage I. The intensity, the expression pattern and the percentage of neoplastic cell staining was recorded and correlated with the histologic type and vascular/lymphatic invasion. Dysadherin was not expressed in non-neoplastic germ cells, neither in CIS/ITGCNU, but it was highly expressed in all types of germ cell tumours, that demonstrated either embryonic phenotype or somatic differentiation, in most terminally differentiated neoplasms, and in all lymphomas. Dysadherin expression did not correlate with vascular invasion. Increased dysadherin expression was correlated with aberrant E-cadherin expression in most tumours. In 17% of embryonal carcinomas colocalisation of dysadherin and membranous E-cadherin staining was noted. This is the first report on dysadherin expression and its association with E-cadherin in testicular tumours. Since dysadherin is not normally expressed in non-neoplastic testis, it is conceivable that it plays a role in the neoplastic transformation of germ cells. In testicular tumours, as in other neoplasms, dysadherin downregulates E-cadherin expression, at least in part.

Evidence for intestinal oxidative stress in obstructive jaundice-induced gut barrier dysfunction in rats.

AIM: An important factor that promotes bacterial and endotoxin translocation in obstructive jaundice is intestinal injury that causes increased permeability. However, little is known of the submicroscopic biochemical events leading to defects of the intestinal barrier. This study was undertaken to investigate the effect of experimental obstructive jaundice on intestinal lipid peroxidation, protein oxidation and thiol redox state. METHODS: Rats were randomly divided into controls, sham operated and bile duct ligated (BDL). After 10 days, intestinal barrier function was assessed by measuring endotoxin in portal and aortic blood. Tissue samples from the terminal ileum were examined histologically and morphometrically, while other samples were homogenized for the determination of lipid peroxidation, protein oxidation and thiol redox state [reduced glutathione (GSH), oxidized glutathione (GSSG), total non-protein mixed disulphides (NPSSR), protein thiols (PSH) and protein disulphides (PSSP)]. RESULTS: Obstructive jaundice compromised intestinal barrier function leading to significant portal and systemic endotoxaemia. The intestinal mucosa in jaundiced rats was atrophic with significantly decreased villous density and total mucosal thickness. Determination of biochemical parameters of oxidative stress in the intestine showed increased lipid peroxidation and protein oxidation in BDL-rats. Thiol redox state revealed the presence of intestinal oxidative stress in jaundiced rats, indicated by a decrease in GSH and increased GSSG, NPSSR and PSSP. CONCLUSIONS: This study shows that experimental obstructive jaundice induces intestinal oxidative stress, which may be a key factor contributing to intestinal injury and leading to endotoxin translocation.

Expression of the cell cycle regulatory proteins p34cdc2, p21waf1, and p53 in node negative invasive ductal breast carcinoma.

AIMS: To look for correlations between expression of cell cycle regulatory proteins p34(cdc2), p21(WAF1), and p53 in node negative invasive ductal breast carcinoma, or between these proteins and clinicopathological parameters, and to assess their prognostic value. METHODS: Immunohistochemistry using formalin fixed, paraffin wax embedded sections from 94 breast carcinomas. Adjacent benign epithelial breast tissue was available in 74 cases. Median follow up was 72 months. RESULTS: Nuclear and cytoplasmic p34(cdc2) expression was seen in 80 and 62 tumours, respectively; nuclear expression was seen in adjacent benign epithelium in 12 cases. p21(WAF1) and p53 were positive in 48 and 21 tumours, respectively. High expression of p34(cdc2) in neoplastic nuclei was associated with higher histological grade and p53 expression, but not with tumour size, steroid receptor status, patient age, menopausal status, recurrence, metastasis, disease free survival (DFS), or overall survival (OS). p34(cdc2) in tumour cytoplasm was associated with p34(cdc2) nuclear positivity, high tumour grade, and DFS in univariate but not multivariate analysis. In contrast, p34(cdc2) expression in benign tissue independently predicted DFS and OS in univariate and multivariate analysis. Expression of p53 was associated with high tumour grade and negative steroid receptors, but not with recurrence, metastasis, DFS, or OS. p21(WAF1) expression was not associated with the examined parameters. CONCLUSIONS: p34(cdc2), p21(WAF1), and p53 expression does not predict outcome in node negative breast carcinoma, although p34(cdc2) expression in benign tissue is related to prognosis. The association between p34(cdc2) and p53 implicates p53 in G2-M cell cycle checkpoint control, possibly via mediators unrelated to p21(WAF1).

Bax protein expression in colorectal cancer: association with p53, bcl-2 and patterns of relapse.

This study evaluated the frequency and the prognostic significance of bax, bcl-2 and p53 proteins in stage B and C adenocarcinomas of the colon and rectum. Paraffin-embedded specimens from 268 patients with colorectal adenocarcinomas, treated with surgery, were assessed; of these 160 cases were Duke's stage B and 108 cases were Duke's stage C disease. Adjuvant chemotherapy was given to all stage C and to 108 out of 160 stage B cancer patients, while those having rectal malignancy also received pelvic radiotherapy. Duke's stage B patients were treated either with surgery alone or with surgery and radiotherapy. The follow-up period at the time of analysis ranged from 12-72 months (median 32 months). Immunohistochemical expression of bax, bcl-2 and mutant p53 proteins was detected with a frequency of 42%, 37% and 48%, respectively. However, the expression was strong only in 17% of tumours, on average. A strong bcl-2 expression was significantly associated with a strong bax expression (p < 0.0001) and with absence of p53 nuclear accumulation (p < 0.005). There was, however, no correlation between bax and p53 proteins. Furthermore, bcl-2 expression was significantly more frequent in grade I and 2 adenocarcinomas compared to grade 3 disease (p = 0.01). In stage B (but not C) adenocarcinomas, bax expression was directly associated with higher risk of local relapse (p = 0.04). By contrast, cases with p53 nuclear accumulation, when they had received adjuvant radiotherapy, were significantly associated with a lower incidence of local relapse (p = 0.01), but a higher rate of distant metastasis (p = 0.06). Multivariate analysis for disease free and overall survival showed that bax expression and high Duke's stage were independent prognostic parameters associated with an unfavourable outcome (p = 0.009 and p = 0.0001, respectively). It was concluded that the immunohistochemical expression of bax is a marker of poor prognosis and of a higher risk of local relapse in patients with colorectal adenocarcinomas. p53 nuclear accumulation is associated with a better local control, following radiotherapy and with a metastatic phenotype. The development of novel monoclonal antibodies recognising specifically the mutated versus the wild type form of proteins would apparently improve the prognostic and predictive value of the immunohistochemically detected apoptotic proteins.

bcl-2/bax ratio as a predictive marker for therapeutic response to radiotherapy in patients with rectal cancer.

Combined radiation therapy and chemotherapy are adjuvant treatments given after surgery to patients with rectal carcinoma. Because apoptosis seems to play a role in tumor response to radiotherapy, the current study investigates whether there is a correlation between the ratio of bcl-2 oncoprotein and bax expression in rectal adenocarcinoma and the clinical response to radiotherapy. Elective colectomy for primary rectal adenocarcinoma followed by adjuvant radiotherapy and chemotherapy was performed on 35 patients. Tumors were staged as B2 (n = 30) and C (n = 5), and were classified as radiation resistant (n = 19, group A) and radiation nonresistant (n = 16, group B). Immunohistochemical study, using the streptavidin-biotin complex technique and monoclonal antibody to bcl-2 and polyclonal antibody to bax protein was used on paraffin sections. Cases were considered positive if at least 5% of tumor cells displayed cytoplasmic staining for bcl-2 or bax. In each tumor, the bcl-2/bax ratio was calculated dividing the percentage of bcl-2-positive cells by the percentage of bax-positive cells. For statistical analysis, the Mann-Whitney rank sum test and Kruskal-Wallis analysis of variance test were used. Rectal tumors of group A displayed significantly greater bcl-2 immunoreactivity (40.2 +/- 4.2) compared with group B (20.2 +/- 3.8). In contrast, expression of bax protein was less in group A (30.3 +/- 3.3) compared with group B (41.3 +/- 2.3). The bcl-2/bax ratio was greater in group A (1.3 +/- 0.1) compared with group B (0.49 +/- 0.1), and was correlated with poor responsiveness to radiotherapy. The current study indicates that in patients with rectal carcinoma an elevated bcl-2/bax ratio in tissue specimens suggests increased tumor resistance to adjuvant radiotherapy. Thus, in such patients, the bcl-2/bax ratio may serve as a potential molecular marker for prediction of tumor prognosis.

Relative risk of cancer in sonographically detected thyroid nodules with calcifications.

PURPOSE: The aim of this prospective study was to evaluate the significance of sonographically detected thyroid calcifications in the diagnosis of thyroid cancer. METHODS: One hundred eighty-eight patients with thyroid disease, including 37 with thyroid cancer, were included in the study. Each patient underwent preoperative, high-resolution sonography to evaluate the thyroid gland for the presence of calcifications. RESULTS: The highest incidence of calcification was found in thyroid cancer (54%), followed by multinodular goiter (40%), solitary nodular goiter (14%), and follicular adenomas (12%). The incidence of cancer was significantly higher in calcified nodules (29%) than in noncalcified nodules in the entire group (14%) (p = 0.019), with a relative risk of 2.5. In the group of solitary thyroid nodules, the incidence of cancer in the calcified nodules (55%) was higher than in the nodules without calcification (23%) (p = 0.016). Multiple noncalcified thyroid nodules harbored cancer in only 5% of cases. Compared with multiple noncalcified thyroid nodules, the solitary calcified nodules demonstrated a relative risk of 22.8. In both the solitary and multiple nodules, the relative risk in the presence of calcification was about the same, around 4. Patients younger than 40 years with calcified nodules constituted a high-risk group, with a relative risk of 3.8 versus 2.5 in patients older than 40 years with calcified nodules. CONCLUSIONS: The detection of thyroid calcifications by sonography is diagnostically valuable, especially in cases involving a solitary nodule or a young person. The presence of calcifications in these cases should raise the suspicion of malignancy. The low incidence of cancer in patients with multiple noncalcified thyroid nodules suggests that a more conservative approach may be appropriate in such cases.

Beneficial effects of growth hormone and insulin-like growth factor I on intestinal bacterial translocation, endotoxemia, and apoptosis in experimentally jaundiced rats.

BACKGROUND: This study was undertaken to investigate the effect of growth hormone (GH) and insulin-like growth factor I (IGF-I), two well-known growth factors, on bacterial translocation, endotoxemia, enterocyte apoptosis, and intestinal and liver histology in a model of experimental obstructive jaundice in rats. STUDY DESIGN: One hundred six male Wistar rats were divided into five groups: I (n = 21), controls; II (n = 22), sham operated; III (n = 22), bile duct ligation (BDL); IV (n = 21), BDL and GH treatment; and V (n = 20), BDL and IGF-I administration. By the end of the experiment, on day 10, blood bilirubin was determined, and mesenteric lymph nodes, liver specimens, and bile from the bile duct stump were cultured. Endotoxin was measured in portal and aortic blood. Tissue samples from the terminal ileum and liver were examined histologically and apoptotic body count (ABC) in intestinal mucosa was evaluated. Mucosal DNA and protein content were also determined. RESULTS: Bilirubin increased significantly after BDL (p < 0.001). Bile from the bile duct was sterile. In group III, MLN and liver specimens were contaminated by gut origin bacteria (significant versus group I and II, p < 0.001, respectively). GH reduced significantly positive cultures (p < 0.01), and IGF-I had no effect. BDL resulted in significant increase in portal and aortic endotoxemia (p < 0.001); treatment with GH and IGF-I reduced it (p < 0.001). Mucosal DNA and protein content were reduced in animals with BDL and after treatment with GH or IGF-I; an increase to almost normal levels was noted in DNA, but not in protein. Overall the ileal architecture remained intact in all animal groups. The ABC increased after BDL. After GH and IGF-I administration, the ABC decreased significantly, and there was no difference between GH and IGF-I treated animals. After BDL, liver biopsies displayed typical changes of biliary obstruction, which were significantly improved after administration of GH and IGF-I. CONCLUSIONS: Treatment with GH and IGF-I in rats with experimental obstructive jaundice reduces endotoxemia, and it improves liver histology. Apoptosis, in the intestinal epithelium, may serve as a morphologic marker of the ileal mucosal integrity, demonstrating the proliferative potential of GH and IGF-I in cases of obstructive jaundice, and this might be of potential value in patients with such conditions.

Expression of bcl-2 and bax in cervical intraepithelial neoplasia and invasive squamous cell carcinoma of the uterine cervix.

Bcl-2 protein together with the pro-apoptotic protein bax, are thought to function by forming homo- and heterotypic dimers which control the progression to apoptosis. In this immunohistochemical study we investigated the expression of bcl-2 and bax apoptosis related proteins in cervical intraepithelial neoplasia and invasive squamous cell carcinoma of the uterine cervix. Twenty-four cervical intraepithelial neoplasias grade 1-2 (CIN I/II), 38 grade 3 (CIN III), and 53 invasive squamous cell carcinomas (ISCC) were investigated by immunohistochemical staining for bcl-2 and bax protein. Bcl-2 immunoreactivity was found in five of the 24 CIN I/II cases (20.8%), 18 of 38 CIN II cases (47.4%) and nine of 53 ISCC cases (17%). The positivity for CIN III was significantly higher than for CIN I/II or ISCC (p=0.0351 and p=0.0018, respectively). The percentage of bax immunopositivity was somewhat higher in CIN III than in CIN I/II but this slight difference was not statistically significant. Correlation of the immunostaining results with tumor grade revealed a significant difference for bcl-2 which was more frequently immunopositive in well-differentiated tumors than in poorly-differentiated tumors. There was no significant relation between bax expression and tumor differentiation. Our results suggest that alterations of bcl-2 and bax expression may occur as a relatively early event in cervical tumorigenesis.

Papillary serous adenocarcinoma of the endocervix: A rare neoplasm. Immunohistochemical profile.

Serous adenocarcinoma of the endocervix is a rare carcinoma similar to the serous carcinoma of the ovary and the endometrium. We report a case of a 63-year-old woman with papillary serous adenocarcinoma arising within the endocervix, describing the clinical presentation and the morphologic characteristics of this rare neoplasm. A detailed immunohistochemical analysis on the expression of low- and high-molecular weight cytokeratins (AE1 and AE3), EMA, CEA, vimentin, B72.3, nm23, estrogen and progesterone receptors, LeuM1 (CD15), p53, Ki-67 antigen, and PCNA by tumor cells has also been carried out, which to our knowledge has not been previously reported.

Microvessel density, proliferating activity, p53 and bcl-2 expression in in situ ductal carcinoma of the breast.

BACKGROUND: Ductal carcinoma in situ (DCIS) of the breast represents a heterogeneous group of lesions that show important differences in biologic behavior. New vessel formation has been reported as a prognostic indicator in breast carcinoma, but little information is available about its significance in DCIS. This study was planned to examine angiogenesis in DCIS in relation to histologic subtype, proliferation activity, p53 and bcl-2 expression. MATERIALS AND METHODS: Paraffin sections from 24 cases of DCIS (9 comedo and 15 non comedo type) were studied immunohistochemically using polyclonal and monoclonal antibodies to von Willebrand factor, Ki-67, p53 (clone 1801) and bcl-2 proteins. The streptavidine-biotin technique with microwave antigen retrieval was employed. RESULTS: Most cases showed enhanced microvessel formation around ducts with DCIS compared to normal ducts. Comedo carcinomas (CCs) showed enhanced neovascularization compared to non comedo carcinomas (NCCs). Growth fraction determination with Ki-67 antibody showed that 78% of the CCs expressed high proliferating activity compared to 27% of the NCCs. p53 immunoexpression was noted in 78% of the CCs and 20% of the NCCs. Bcl-2 immunoreactivity was observed in 67% of the total cases in 58% of which there was no association with p53 expression. However, an association was found between neovascularization and overexpression of Ki-67 and p53. CONCLUSIONS: This study suggests that neovascularization is an early phenomenon in breast neoplasia and is apparent as early as the in situ stage. CCs express a more aggressive immunophenotype, compared to the other DCIS subtypes, characterized by increased stromal interaction, high proliferating activity, p53 overexpression and a near lack of bcl-2 immunostaining.

Nonabsorbable antibiotics reduce bacterial and endotoxin translocation in hepatectomised rats.

There is increasing evidence that septic complications, occurring after major hepatectomies, may be caused by gram negative bacteria, translocating from the gut. We investigated in rats, the effect of extended hepatectomy on the structure and morphology of the intestinal mucosa as well as on the translocation of intestinal bacteria and endotoxins. We also examined the effect of nonabsorbable antibiotics on reducing the intestinal flora and consequently the phenomenon of translocation by administering neomycin sulphate and cefazoline. Hepatectomy was found to increase translocation, while administration of nonabsorbable antibiotics decreased it significantly. In addition, hepatectomy increased the aerobic cecal bacterial population, which normalised in the group receiving antibiotics. Among the histological parameters evaluated, villus height demonstrated a significant reduction after hepatectomy, while the number of villi per cm and the number of mitoses per crypt, remained unchanged. Our results indicate that administration of nonabsorbable antibiotics presents a positive effect on bacterial and endotoxin translocation after extended hepatectomy, and this may be related to reduction of colonic bacterial load as an intraluminal effect of antibiotics.

Nuclear grooves in fine needle aspiration (FNA) biopsies of breast lesions.

The present study was undertaken to evaluate the significance of grooved nuclei as an additional diagnostic criterion for primary breast carcinoma as well as their association with tumor grade in cytologic material obtained by fine needle aspiration (FNA). Cytologic slides of 105 cases of breast carcinoma (89 ductal, 10 lobular, 3 medullary, 3 mucinous) and 39 cases of benign lesions were reviewed. Histologic confirmation was obtained in all cases. In each case the number of grooved nuclei per 200 well-preserved cells per slide was recorded. Nuclear grooves were found in 62% (65/105) of the malignant and in 36% (14/39) of the benign lesions. This cytomorphologic feature was observed in all histologic types of breast carcinoma. Furthermore, nuclear grooves were present in all grades of ductal carcinoma, and at about the same frequency. Our findings indicate that in the mammary gland nuclear grooving cannot be considered as a criterion of malignancy, and is not helpful either in differentiating the various histologic types or in grading breast tumors in FNA preparations.