Retinoblastoma gene product and P21 (WAF1, CIP1) protein expression in non Hodgkin's lymphomas: a multivariate survival analysis.

We evaluated immunohistochemically the expression of two negative regulators of the cell cycle, namely retinoblastoma gene product (pRb) and WAF1/Cip1 gene product (p21), in paraffin sections from 93 patients with non-Hodgkin's lymphomas (NHL) and related it to clinicopathological parameters, proliferative fraction, p53 expression and survival. Patients were followed until death (n=33) or for an average of 52 months (60-160). Rb labelling index (LI) increased with malignancy grade and proliferative activity but was unrelated to other clinicopathological parameters. In 33% of cases, especially those of the aggressive groups, we observed diminished pRb expression (i.e. low pRb/Ki-67 ratio). p21 expression on the other hand correlated only with histological grade, Rb LI and p53 LI. In multivariate analysis, Rb LI was a negative predictor of disease-free survival but was linked to a higher probability of complete response. However, diminished pRb expression as well as p21 expression were not statistically significant prognostic indicators. Our results suggest that pRb as a cell cycle related molecule may play an important role in determining prognosis and therapeutic response in NHL patients.

Sensitive differential detection of genetically related mycobacterial pathogens in archival material.

A polymerase chain reaction (PCR) assay targeted to the immunogenic protein MPB64 gene was used to detect members of the Mycobacterium tuberculosis complex, and an outward-primed PCR (OPPCR) designed on the IS6110 element allowed differentiation between Mycobacterium bovis and Mycobacterium tuberculosis. Additionally, the amplification of IS1110 and 16S ribosomal RNA sequences combined with a dot blotting assay were able to differentially detect Mycobacterium avium, Mycobacterium intracellulare, and Mycobacterium paratuberculosis. The validity of the experimental procedure was tested on reference material and formalin-fixed paraffin-embedded samples from patients with tuberculosis, sarcoidosis, or Crohn disease. We demonstrated mycobacterial DNA in 59 of 75 cases with histologic lesions typical of tuberculosis; we detected M tuberculosis and M paratuberculosis in 6 of 25 sarcoidosis cases and in 7 of 20 Crohn disease specimens, respectively. The proposed diagnostic procedure is directly applicable to archival material and allows differentiation of genetically related mycobacterial pathogens in more detail than other molecular methods. It provides a tool for the diagnostic study of tuberculosis, sarcoidosis, and Crohn disease.

Effect of granulocyte colony-stimulating-factor administration on tissue regeneration due to thioacetamide-induced liver injury in rats.

It has been shown recently that granulocyte colony-stimulating factor (G-CSF) accelerates and enhances the hepatocyte proliferative capacity of partially hepatectomized rats. In the present study, we investigated the effect of G-CSF administration in a rat model of liver injury and regeneration, induced by thioacetamide (TAA) injection. TAA (300 mg/kg body weight) was injected intraperitoneally in male Wistar rats, and this was followed by administration of either saline (group A) or G-CSF at a dose of 150 microg/kg body weight (group B), 24 hr later. The animals were killed at different time points after TAA treatment and the rate of tritiated thymidine incorporation into hepatic DNA, the activity of the enzyme thymidine kinase (EC 2.7.1.21) in the liver, and the assessment of the mitotic index of hepatocytes, were employed to estimate liver regeneration. The administration of TAA caused severe hepatic injury, recognized histopathologically and by the raised activities of the serum hepatic enzymes aspartate and alanine aminotransferases. The hepatic injury, which peaked 36 hr after TAA injection, was followed by a regenerative process of hepatocytes presenting peaks at time points of 48 and 60 hr (group A). The administration of G-CSF 24 hr after the injection of TAA (group B) caused a statistically significantly increase in the hepatocyte proliferation indices examined (P < 0.001), compared to those found in group A at the same time points. It was concluded that G-CSF administration enhanced the hepatocyte proliferative capacity in this model of liver injury induced by TAA administration.

Effect of hepatic stimulator substance administration on tissue regeneration due to thioacetamide-induced liver injury in rats.

BACKGROUND: Hepatic stimulator substance (HSS) is a known hepatic growth factor that appears to be organ-specific but species-nonspecific. In the present study we investigated the effect of HSS administration in a rat model of liver injury and regeneration induced by thioacetamide (TAA) injection. METHODS: TAA (300 mg/kg body weight) was injected intraperitoneally in male Wistar rats (group I). HSS (50 mg protein/kg body weight) was administered intraperitoneally either at 24 h (group II) or at 36 h (group III) after TAA treatment. The animals were killed at different time points after TAA injection, and the rate of tritiated thymidine incorporation into hepatic DNA, the activity of the enzyme thymidine kinase in liver, and the assessment of the mitotic index in hepatocytes were used to estimate liver regeneration. RESULTS: The administration of TAA caused severe hepatic injury recognized histopathologically and by increased activities of the serum hepatic enzymes aspartate and alanine aminotransferases. The hepatic injury, which peaked at 24 h and 36 h after TAA injection, was followed by a regenerative process of hepatocytes which presented peaks after 48 h and 60 h (group I). The regenerative process of hepatocytes remained unaffected when HSS was administered 24 h after the injection of TAA (group II). In the case of HSS administration 36 h after the injection of TAA (group III) the examined indices of hepatocyte proliferation were statistically significantly increased at 48 h (P < 0.001), compared with those observed in group I. CONCLUSIONS: The administration of HSS enhanced the hepatocyte proliferative capacity, induced by TAA treatment, depending on the time of its administration.

Effect of interferon-alpha2b administration on rat liver regeneration after partial hepatectomy.

The purpose of the present study was to delineate the effect of interferon-alpha2b (IFN-alpha2b) administration on the liver regenerative capacity after partial hepatectomy in rats. The administration of IFN-alpha2b simultaneously with partial hepatectomy did not affect hepatic proliferation in a statistically significant manner. When IFN-alpha2b was administered either 2 or 12 hr postoperatively, an inhibition of hepatocyte proliferation was observed 24 hr postoperatively, while at further time intervals up to 48 hr, DNA synthesis remained similar to that observed in the simply partially hepatectomized rats. The enzyme thymidine kinase (TK), has been implicated in the suppression of proliferation in interferon-treated cell cultures. In all IFN-alpha2b-treated groups of rats, alterations of TK activity were observed without being correlated to the liver regenerative status. Additionally, the administration of the polyamine putrescine in partially hepatectomized rats treated at the time of surgery with IFN strongly enhanced TK activity, but did not affect DNA biosynthesis. In the above-mentioned in vivo model of controlled cellular proliferation, the administration of IFN-alpha2b affected the rate of hepatocyte proliferation depending on the time of its administration; this effect was not correlated to the enzymatic activity of TK, as inhibited TK activity is responsible for the suppressed DNA synthesis in in vitro systems.

Effect of two forms of granulocyte-colony-stimulating factor on hepatic regeneration after 70% partial hepatectomy in rats.

1. The purpose of this study was to determine whether the commercially available forms of granulocyte-colony-stimulating factor exert the same beneficial effect on hepatic regeneration after 70% partial hepatectomy in rats. Adult male Wistar rats received either the two commercially available forms of granulocyte-colony-stimulating factor (Filgrastim or Lenograstim), or saline, simultaneously with partial hepatectomy. Hepatic regeneration was documented by determining [3H]thymidine incorporation into hepatic DNA, liver thymidine kinase activity, mitotic index and proliferating cell nuclear antigen immunostaining, at various time points after partial hepatectomy. 2. DNA biosynthesis, liver thymidine kinase activity and mitotic index of hepatocytes were not only enhanced (P < 0.001) in rats that received 150 micrograms of Filgrastim or Lenograstim/kg of body weight, but occurred earlier than in saline-treated partially hepatectomized rats. The administration of both forms of granulocyte-colony-stimulating factor, at the dose of 15 micrograms/kg of body weight, did not affect liver proliferative capacity, compared with observations in simply partially hepatectomized rats. High mitotic and proliferating cell nuclear antigen indices appeared earlier than those estimated in simply partially hepatectomized rats, when 150 micrograms of Filgrastim or Lenograstim/kg of body weight were administered. 3. These findings suggest that both pharmacologically available forms of granulocyte-colony-stimulating factor at a dose of 150 micrograms/kg of body weight are able to augment liver regenerative capacity, to the same extent, in this animal model of controlled hepatic proliferation.

Granulocyte colony-stimulating factor administration reverses cadmium-associated inhibition of hepatocyte regeneration.

OBJECTIVE: To document whether the administration of granulocyte colony-stimulating factor (G-CSF) enhances the impaired regenerative response of hepatocytes to partial hepatectomy (PH), in cadmium-pretreated partially hepatectomized rats. MATERIALS AND METHODS: Rats were injected intraperioneally with 2.5 mg CdCl2/kg body weight, 24h before PH. G-CSF (1500 or 150 micrograms/kg body weight) or saline was administered intraperitoneally in cadmium-pretreated partially hepatectomized rats at the same time as PH. The liver regenerative process was estimated 24h after PH. [3H] thymidine incorporation into liver DNA, liver thymidine kinase (TK) activity, mitotic index and proliferating cell nuclear antigen (PCNA) immunostaining were used as indices of hepatocyte proliferation. RESULTS: G-CSF administration in cadmium-pretreated partially hepatectomized rats restored the suppressed DNA biosynthesis and TK activity (P < 0.001), to levels similar to those found in rats that were partially hepatectomized only. The mitotic index and the percentage of PCNA positive nuclei in hepatocytes were also enhanced in G-CSF administered cadmium-pretreated partially hepatectomized groups of rats. CONCLUSION: The administration of G-CSF triggers events that restore the impaired liver regeneration in this model of reduced hepatocyte proliferation.

Efficacy of the Isaacs Endometrial Cell Sampler in the cytologic detection of endometrial abnormalities.

The efficacy of the Isaacs Endometrial Cell Sampler to obtain specimens for cytologic examination to detect both hormonal disturbances and precursors of malignancy of the endometrium was assessed in 120 symptomatic women. Correlation of the cytologic results with the histologic diagnosis on curettage specimens showed a diagnostic accuracy of 96.3%. The cytologic criteria for diagnosing samples obtained with the Isaacs device are presented.