Proliferating cell nuclear antigen (PCNA) immunostaining--a prognostic factor in ovarian cancer?

The measurement of tumour cell proliferation is becoming increasingly recognised in defining prognostic groups. Proliferating cell nuclear antigen (PCNA) immunolocalisation can be used as an index of cell proliferation and may define the extent of departure from normal growth control. The monoclonal antibody PC10 stains PCNA in archival paraffin-embedded tissue. This study investigates its potential as a prognostic marker in early and advanced ovarian cancer. A three-stage immunoperoxidase technique was developed to detect the monoclonal antibody PC10. Archival paraffin-embedded tissue from 19 stage I ovarian tumours (13 malignant and six borderline) and 79 advanced (stage IIb-IV) ovarian tumours (patients entered into the Third North-West Thames Ovarian Cancer Trial) was immunostained with PC10. PC10 immunostaining was performed successfully in 91.8% of cases. The PC10 labelling index (PC10 LI) ranged from 1.5% to 88% with a mean value of 47.4%. Stage I borderline tumours had significantly lower PCNA labelling indexes than stage I malignant tumours (P < 0.048). In advanced disease there was an inverse correlation between PC10 and overall survival, and in those patients who underwent good debulking surgery (37 patients with disease < 2 cm diameter) a low PC10 value (< 36.5%) correlated with improved survival (log-rank trend test for survival, chi 2 = 5.75, P = 0.017). PCNA immunostaining defines a good prognostic subgroup in adequately debulked patients with ovarian cancer.     

CVT-313, a specific and potent inhibitor of CDK2 that prevents neointimal proliferation

The activity of cyclin-dependent kinase 2 (CDK2) is essential for progression of cells from G1 to the S phase of the mammalian cell cycle. CVT-313 is a potent CDK2 inhibitor, which was identified from a purine analog library with an IC50 of 0.5 microM in vitro. Inhibition was competitive with respect to ATP (Ki = 95 nM), and selective CVT-313 had no effect on other, nonrelated ATP-dependent serine/threonine kinases. When added to CDK1 or CDK4, a 8.5- and 430-fold higher concentration of CVT-313 was required for half-maximal inhibition of the enzyme activity. In cells exposed to CVT-313, hyperphosphorylation of the retinoblastoma gene product was inhibited, and progression through the cell cycle was arrested at the G1/S boundary. The growth of mouse, rat, and human cells in culture was also inhibited by CVT-313 with the IC50 for growth arrest ranging from 1.25 to 20 microM. To evaluate the effects of CVT-313 in vivo, we tested this agent in a rat carotid artery model of restenosis. A brief intraluminal exposure of CVT-313 to a denuded rat carotid artery resulted in more than 80% inhibition of neointima formation. These observations suggest that CVT-313 is a promising candidate for evaluation in other disease models related to aberrant cell proliferation.     

Value of serum inorganic phosphate in the diagnosis of ischemic bowel disease

To clarify the value of the serum inorganic phosphate concentration in the diagnosis of ischemic bowel disease, a retrospective study of 24 patients with various causes of intestinal ischemia was carried out. Only 25 percent of the patients had elevations of their serum phosphate concentrations. These patients had the combination of extensive bowel injury, acute renal insufficiency, and acidosis. Mortality was significantly increased in these patients. Thus, the serum phosphate concentration was not a sensitive indicator of ischemic bowel disease, but elevations did predict extensive injury and poor prognosis.     

Identification and characterization of a lysis module present in a large proportion of bacteriophages infecting Streptococcus thermophilus

A lysis module encoded by the temperate bacteriophage phiO1205 was identified. This lysis module contains a lysin gene, designated lyt51, and two putative holin-encoding genes, designated lyt49 and lyt50. lyt51 encodes a lytic enzyme specifically directed against streptococcal cell walls. Similar to other phage-encoded lysins, Lyt51 appears to have a modular design in which the N-terminal portion corresponds to its enzymatic activity while the C-terminal region is responsible for its substrate binding specificity. The two putative holin-encoding genes, lyt49 and lyt50, located immediately upstream of lyt51, were identified on the basis of their homology to other identified holin-encoding genes. Expression of lyt49 or lyt50 in Escherichia coli was shown to cause cell death and leakage of the intracellular enzyme isocitrate dehydrogenase into the growth medium without apparent lysis of the cells. Southern blotting experiments demonstrated that at least one of the three components of the identified lysis module is present in all members of a large collection of bacteriophages, indicating that components of this lysis module are widespread among bacteriophages infecting Streptococcus thermophilus.     

Spectrophotometric and atomic absorption spectrometric determination of ramipril and perindopril through ternary complex formation with eosin and Cu(II)

Two sensitive, spectrophotometric and atomic absorption spectrometric procedures are developed for the determination of ramipril and perindopril. Both methods are based on the formation of a ternary complex, extractable with chloroform, between copper(II), eosin and the two cited drugs. Spectrophotometrically under the optimum condition, the ternary complexes showed an absorption maximum at 535 nm, with apparent molar absorptivities of 6.55 and 4.00 x 10(3) mol(-1) x cm(-1) and Sandell's sensitivities of 5.80 x 10(-2) and 1.04 x 10(-1) microg x cm(-2) for perindopril and ramipril, respectively. The solution of ternary complex obeyed Beer's law in concentration ranges 10-60 and 20-100 microg x ml(-1) for perindopril and ramipril, respectively. The proposed method was applied to the determination of the two cited drugs in pharmaceutical tablets. The atomic absorption spectrometric method, directly through the quantitative determination of copper content of the organic extract of the complex, was also investigated for the purpose of enhancing the sensitivity of the determination. The spectrophotometric and atomic absorption spectrometric procedures hold their accuracy and precision well when applied to the determination of ramipril and perindopril dosage forms.     

A comparison of alternate immunization regimes for measles in vaccinated populations

Infants today lose maternal measles antibody sooner than in the past. This is related to demographic changes in maternal immunization. Data for rates of decay of maternal antibody and seroconversion after measles vaccination for infants born to naturally immune (Group 1) or vaccinated (Group 2) mothers have been used to evaluate two vaccination schedules: Regime 1, measles-mumps-rubella (MMR) at 1 year of age and Regime 2, monovalent measles at 6 months followed by MMR at 15 months of age. Regime 2 costs less because MMR can be administered at 15 months with the last pentavalent booster. Months of protection/1000 children aged 0-15 months (child-months of protection) were estimated for infant populations ranging from 0 to 100% Group 1 for Regimes 1 and 2. Regime 1 provides more child-months of protection only for 100% Group 1 populations. For the study population Regime 2 provided at least 17% more child-months of protection than Regime 1. Regime 2 provides increased medical and financial benefits in proportion to the number of Group 2 infants in the population and thus is ever more advantageous for today's increasingly vaccinated populations.     

Unrelated donor bone marrow transplantation for chronic myelogenous leukemia: a decision analysis

BACKGROUND: Chronic myelogenous leukemia (CML) is an indolent but ultimately fatal disease. Because the natural history of CML varies and quality of life with CML may be excellent until shortly before death, deciding whether and when to pursue unrelated donor bone marrow transplantation is often difficult. OBJECTIVE: To compare early transplantation, delayed transplantation, and no transplantation for patients with chronic-phase CML on the basis of discounted, quality-adjusted life expectancy. DESIGN: A markov model comparing different strategies was constructed. This model considers patient age, quality of life, risk aversion, and the competing risks for CML progression and transplant toxicity. SETTING: Therapeutic decision at the time of diagnosis of CML. PATIENTS: The base case is a 35-year-old patient with intermediate-prognosis CML. Younger and older patients with better and worse prognoses are also evaluated. INTERVENTION: Early transplantation, delayed transplantation, and no transplantation. MEASUREMENTS: Quality-adjusted, discounted life expectancy. RESULTS: For patients with newly diagnosed CML, transplantation within the first year provides the greatest quality-adjusted expected survival, although this benefit decreases with increasing patient age. For a 35-year-old patient with intermediate-prognosis CML, transplantation within the first year results in 53 more discounted, quality-adjusted years of life expectancy than does no transplantation. This finding is robust even with varying baseline assumptions. CONCLUSIONS: These results support the use of early unrelated donor bone marrow transplantation for most patients with CML.     

Isolation of cDNA clones from an osteosarcoma-ROS17/2.8 library by differential hybridization

We have used differential hybridization to isolate and characterize two novel cDNAs expressed in chondrocytes and some osteoblastic cells. A rat osteosarcoma ROS17/2.8 cDNA library was screened and cDNA clones hybridizing strongly to radiolabeled porcine calvaria cDNA but weakly to a control radiolabeled cDNA were isolated. Two clones were obtained--p.6.1 and p.10.15. A radiolabeled probe of p10.15 was shown to hybridize specifically to a 2.3 Kb message RNA from a chondrogenic clonal cell population from rat calvaria-RCJ 3.1C5.18, and the mRNA was downregulated by 1,25 (OH)2D3, which inhibits chondrogenesis in these cells. The other clone, p6.1, was found to hybridize to a 0.95 Kb message that is expressed in rat liver, kidney, lung, muscle, and brain, but not expressed in spleen and expressed only in low levels in thymus.