Naphthalimido derivatives as antifolate thymidylate synthase inhibitors

A new series of N-(substituted)benzyl-1,8-naphthalimides 4, structurally related to the previously reported thymidylate synthase (TS) inhibitor naphthaleins 3, were synthesized and compounds tested for their inhibition of several species of TS. Moreover, their in vitro cytotoxicity together with antimycotic and antibacterial properties were assayed. While no activity was detected in the antibacterial tests, the m-nitro (4ae) and the p-nitro (4af) derivatives were found able to partially inhibit TS at low micromolar concentrations. Introduction of nitro or (substituted)-amino groups in position 4 of the naphthalic ring always led to less active compounds.     

The incidence of Cytomegalovirus (CMV) antigenemia and CMV disease is reduced by highly active antiretroviral therapy

Cytomegalovirus (CMV) infection was one of the most common opportunistic infections in AIDS patients, leading to blindness or life-threatening disease in about 40% of patients in the later stages of AIDS before highly active antiretroviral therapy (HAART). In a retrospective multicenter study we investigated the incidence of CMV retinitis and organ involvement in Northern Italy before (1995 and 1996) and after the introduction of HAART (1997 and 1998) as well as the data regarding CMV antigenemia. We found a sharp drop in the incidence of CMV disease in AIDS patients as well as a decline in the incidence of relapses of CMV-disease after the widespread introduction of HAART.c Moreover, there was a decrease in the incidence of antigenemia-positive cases in AIDS patients in the era of HAART and the median CMV viral load was significantly higher in patients who didn't receive HAART than in patients who received HAART (p= 0.001, ttest).     

Genotoxicity biomarkers in the assessment of heavy metal effects in mussels: experimental studies.

Heavy metals are stable and persistent environmental contaminants. The range of metal concentrations is generally below acute thresholds in coastal areas, where recognition of chronic sublethal effects is more relevant. Evidence of long-term adverse effects, such as cancer, due to heavy metals in marine animals comes from a number of field and experimental studies. The mechanism of metal carcinogenicity remains largely unknown, although several lines of experimental evidence suggest that a genotoxic effect may be involved. The aim of our study was to evaluate the sensitivity of genotoxicity tests, alkaline elution and micronucleus test, as biomarkers for the detection of heavy metals in mussels as the sentinel species. Experimental studies were carried out on Mytilus galloprovincialis exposed in aquarium (5 days) to different concentrations of three selected metal salts, CuCl2 (5, 10, 20, 40, 80 micrograms/l/a), CdCl2 (1.84, 18.4, 184 micrograms/l/a), and HgCl2 (32 micrograms/l/a), and to a mixture of equimolar doses of the three metals to study the results of their joint action. Metallothionein quantitation was used as a marker of metal exposure. Lysosomal membrane stability was applied to evaluate the influence of physiological status on genotoxic damage. The ranking of genotoxic potential was in decreasing order: Hg > Cu > Cd. Cu and Hg caused an increase of DNA single-strand breaks and micronuclei frequency. Cd induced a statistical increase of DNA damage, but gave negative results with the micronucleus test. A relationship between genotoxic effects and metallothionein content was observed. Reduction in lysosomal membrane stability with the increasing concentration of heavy metals was also evident.     

Evaluation of the attenuation coefficients in normal and pathological breast tissue

The present paper reports on measurements of frequency-dependent attenuation in normal and pathological breast tissue. Measurements were performed by using pulsed transmitted ultrasound. Five groups of breast specimens including fatty tissue, fibrofatty parenchyma and fibrosis, malignant tumours with and without productive fibrosis (infiltrating ductal carcinoma scirrhous type and medullary carcinoma, respectively) have been studied. The results of the attenuation measurements indicate that the attenuation coefficient is lower for tissues with large predominance of cells (fatty tissue, medullary carcinoma) and increases with collagen fibre content (infiltrating ductal carcinoma scrirrhous type, fibrosis, fibrofatty). A comparative nonlinear (best fitting) and linear analysis of the attenuation curves shows that it does not matter whether one uses a linear or nonlinear equation to describe the attenuation curves.     

Changes in body temperature and urinary cortisol after routine immunization in babies with intrauterine growth retardation

Aim : To investigate whether infants with intrauterine growth retardation (IUGR) experience different changes in temperature and cortisol excretion after routine immunization compared with normal healthy infants. Methods : Overnight deep body temperature and urinary cortisol to creatinine ratios were measured on the night after immunization and a control night in normal and IUGR infants. Results : In 60 normal infants, first vaccination at about 10 wk of age led to a significant increase in minumum overnight temperature compared to the control night, mean rise 0.25°C (95% CI, 0.12 to 0.38). In 35 IUGR infants the mean rise in temperature between immunization night and control night was 0.35°C (95% CI, 0.15 to 0.55). The increases in minimum temperature did not differ significantly between the normal and IUGR infants ( p = 0.11). Cortisol to creatinine ratios measured from overnight urine samples showed that 23 IUGR infants had consistently higher levels than 39 normal infants; control night medians 34 and 15 ( p = 0.01) and immunization night medians 56 and 26 ( p= 0.02), respectively. However, the percentage increase did not differ significantly between the IUGR infants and the normal infants. A smaller number of second immunizations were studied, but no significant differences were found.

Conclusion : These results suggest that although the impact of immunization is the same for IUGR and normal infants, because IUGR infants are less mature and at greater stress before immunization, the absolute levels that they experience after immunization are higher than those for normal infants.     

Pulmonary embolism after hip or knee replacement: postoperative changes on pulmonary scintigrams in asymptomatic patients

Serial pulmonary imaging has proved to be effective in the evaluation of patients undergoing total joint arthroplasty. A clinical dilemma arises in asymptomatic patients whose postoperative pulmonary images differ from the preoperative images. The authors prospectively evaluated 403 patients with serial imaging to determine the significance of changed postoperative images in asymptomatic patients undergoing total hip or knee arthroplasty. Twenty-two (5.5%) patients had significant changes on postoperative images. Seventeen were asymptomatic; all but one underwent pulmonary angiography. Documented pulmonary emboli were demonstrated in 100% of patients whose postoperative images changed to indicate a high probability of pulmonary embolism, 71% whose images changed to a moderate probability, and 0% whose images changed to indeterminate probability. Overall, pulmonary emboli occurred in 76% of all asymptomatic patients with significantly change postoperative images. Asymptomatic pulmonary embolism is a significant occurrence after total hip or knee repair, and a changed lung scan with appropriate clinical evaluation is an accurate indicator of pulmonary emboli in asymptomatic postarthroplasty patients.     

Constitutive expression of human cytomegalovirus (HCMV) glycoprotein gpUL75 (gH) in astrocytoma cells: a study of the specific humoral immune response.

The humoral immune response to gpUL75 (gH) was determined in different groups of human cytomegalovirus (HCMV) infected subjects using a full-length glycoprotein constitutively expressed in an astrocytoma cell line. The recombinant molecule consisted of two distinct isoforms resembling the authentic protein of infected cells. Separated from the interactions of other viral gene products gH failed to form an oligomeric complex, thus exhibiting exclusively epitopes present on the monomer. Ninety five percent of serum samples from latently-infected healthy adults revealed the presence of gH-specific IgG. Moreover, examination of sequential sera from immunocompromised and immunocompetent individuals undergoing active HCMV infection demonstrated that antibodies to gH occurred in most cases simultaneously with those to the abundant surface antigen gpUL55 (gB) and at similar titres. Appearance of this response was correlated with a considerable increase of the virus-neutralizing activity and most likely associated with restriction of viral dissemination during subsequent viremic episodes. Together, these results suggest that glycoprotein H of HCMV is like gB, a highly immunogenic component of the infectious particle.     

In vivo radiofrequency ultrasound analysis of normal human heart structures

Twenty young subjects were studied with a microprocessor system for quantitative analysis of backscattered radiofrequency (RF) signals from normal heart structures. This system allows an "on line" quantitative evaluation of the amplitude of the RF "native" signal, before the chain of processing and display, with the acquisition gate displayed on a conventional M-mode machine. Septum, posterior wall, and anterior mitral leaflet were analyzed. The gate length was kept at 3 microseconds (2.35 mm) for the ventricular walls (excluding endo- and epicardial reflections), and at 1 microsecond (0.8 mm) for the mitral valve. Integrated backscatter index (IBI) was calculated as the time integral of [u(t)[, where u(t) = i(t) X s(t); is the time sequence of backscattered echoes and s(t) is the time gate delimiting the thickness of the insonated tissue. The IBI was expressed in percent, normalized for the pericardial interface (the strongest reflection was assumed to be 100%). The percent IBI for the septum was found to be 22 +/- 4%; for the posterior wall it was 17 +/- 3%; for the anterior mitral leaflet it was 5 +/- 2%. A second reading of the same structures was performed by the previous observer and by a new one. Good intraobserver (r = 0.92) and interobserver (r = 0.88) correlations were obtained. In conclusion, a regional variation in echo amplitude from different heart structures can be observed in man. This set of values can be used as normal values for future studies in pathologic conditions.