Cytogenetic analysis of melanoma cell lines: subclone selection in long-term melanoma cell cultures

We employed G-banding cytogenetic analysis to follow the clonal constitution of short-term cultures of metastatic malignant melanoma compared to their long-term cultures. Eight metastatic melanoma cell lines were analyzed. No long-term culture was found to be identical to its line of origin. In all cultures there was a selection of one subclone and emergence of its own subclones. In the majority of cultured tumors (5/8), this process was associated with a decrease in the number of subclones composing the line. We suggest that subclone selection in long-term tumor cultures can be associated with a change in phenotype. Therefore, caution is required when employing long-term cultures for research and therapy.     

mtDNA depletion myopathy: elucidation of the tissue specificity in the mitochondrial thymidine kinase (TK2) deficiency

Decreased mitochondrial thymidine kinase (TK2) activity is associated with mitochondrial DNA (mtDNA) depletion and respiratory chain dysfunction and is manifested by isolated, fatal skeletal myopathy. Other tissues such as liver, brain, heart, and skin remain unaffected throughout the patients' life. In order to elucidate the mechanism of tissue specificity in the disease we have investigated the expression of the mitochondrial deoxynucleotide carrier, the mtDNA content and the activity of TK2 in mitochondria of various tissues. Our results suggest that low basal TK2 activity combined with a high requirement for mitochondrial encoded proteins in muscle predispose this tissue to the devastating effect of TK2 deficiency.     

Nonsyndromic paucity of interlobular bile ducts: report of 10 patients

OBJECTIVES: Only a few reports of nonsyndromic paucity of interlobular bile ducts (NS-PILBD) have been published. The authors' aim was to outline the clinical and laboratory profile of patients with NS-PILBD diagnosed at a tertiary referral center. METHODS: The authors reviewed all the reports of pediatric liver biopsies performed between 1991 and 2000 at their institution. Upon diagnosis of NS-PILBD, patients' records were examined for clinical, laboratory, and histologic data, and liver biopsy specimens were re-evaluated. RESULTS: Three hundred biopsies were performed in children during the study period, of which 64 were in infants younger than 1 year. NS-PILBD was diagnosed in 10 of 64 (16%) biopsy specimens. Mean age at presentation was 10 days (range, 1 day-6 weeks), and mean follow-up was 4.5 years (range, 1-9 years). An underlying condition was identified in 70% of children with NS-PILBD: namely congenital cytomegalovirus (n = 2), progressive familial intrahepatic cholestasis (PFIC, n = 2), mitochondrial DNA depletion (n = 1), Niemann-Pick type C (n = 1), and arthrogryposis multiplex congenita, renal dysfunction, and cholestasis (ARC syndrome; n = 1). All children presented with jaundice. Four children had initially acholic stools. At their last follow-up visit, failure to thrive was present in five children, and cholestasis in six children. Mortality was noted only in children with metabolic diseases (n = 2). CONCLUSIONS: In the study, NS-PILBD was common in young children undergoing liver biopsy. Although NS-PILBD is nonspecific, a wide survey for inborn errors of metabolism should be included in the diagnostic work-up of NS-PILBD. In the authors' center, the association of certain metabolic diseases with NS-PILBD carries a grave prognosis.     

The burden of acute otitis media on the patient and the family

The aim of our study was to determine the burden of acute otitis media (AOM) on patients and their families. Parents of children with AOM were interviewed with regard to the week preceding the AOM diagnosis and every 3 days henceforth for an additional 21 days. The interview included information on loss of workdays, use of health care services and impact on the patient's and family's quality of life. Parents of age- and neighbourhood-matched controls were interviewed in an identical manner. A total of 150 patients and 51 controls were included in the analysis. The following variables differed significantly ( P <0.001) between patients and controls (mean ± SD): non-routine days 18.5±11.0 in patients versus 3.4±6.5 in controls; number of visits to primary health centres 2.6±1.6 versus 0.4±0.6; number of emergency room visits 0.2±0.5 versus 0.1±0.02 and number of visits to an otolaryngology clinic 0.3±0.6 versus 0. Days of antibiotic and over the counter drug use were 9.0±5.6 versus 0.3± 0.9 and 7.0±6.0 versus 4.9±6.0, respectively per episode. The mean loss of workdays per child was 1.6±1.8 in patients versus 0.25±0.6 in controls, for working mothers and 0.6±1.1 versus 0.1±0.4 for working fathers; duration of absenteeism from day care facilities was 3.5±2.5 versus 0.9±2.7. Conclusion: Acute otitis media significantly reduces the quality of life of both child and parents, causes substantial use of medical services and significant loss of workdays.Abbreviations AOM acute otitis media - OTC over the counter     

Effect of a nonavalent conjugate vaccine on carriage of antibiotic-resistant Streptococcus pneumoniae in day-care centers

BACKGROUND: In the developed societies, day-care centers (DCCs) play an important role in the spread of antibiotic-resistant pneumococci both within the facility and from the facility to the community. This study was conducted to determine the effect of a nonavalent pneumococcal conjugate vaccine (PCV-9) on the carriage of antibiotic-resistant pneumococci in the DCC. SUBJECTS AND METHODS: Healthy DCC attendees ages 12 to 35 months were randomized to receive either PCV-9 or a control vaccine (conjugate meningococcus C vaccine) in a double blinded manner. Nasopharyngeal Streptococcus pneumoniae cultures were obtained from each subject before vaccination, monthly during the first year of follow-up and every 2 to 3 months during the second year of follow-up. For each isolate the serotype and antibiotic susceptibility were determined. RESULTS: A total of 132 and 130 evaluable toddlers received either PCV-9 or the control vaccine, respectively. In total 3748 cultures were obtained, of which 2450 (65%) were positive for S. pneumoniae. The resistance rates to penicillin, trimethoprim-sulfamethoxazole and erythromycin were 36, 35 and 16%, respectively. Resistance rates to > or =1 and > or =3 antibiotic categories were 52 and 9%, respectively. Antibiotic resistance was found mainly in the 5 serotypes included in the pneumococcal conjugate vaccines (6B, 9V, 14, 19F and 23F) and in 2 related serotypes (6A and 19A). In the vaccinated group a clear and significant reduction of the carriage rate of the serotypes included in the vaccine and the related serotype 6A as well as an increase in the carriage rate of the serotypes not included in the vaccine were observed. In parallel a significant decrease in carriage rate of antibiotic-resistant pneumococci was observed. The reduction of carriage of antibiotic-resistant pneumococci was seen in all age windows but was greater in the age window <36 months. CONCLUSIONS: The carriage rate of antibiotic-resistant S. pneumoniae, including multiply resistant S. pneumoniae, in DCC attendees is high. Pneumococcal conjugate vaccines seem to be an important tool for reducing the carriage rate of antibiotic-resistant pneumonia in DCCs.     

Lamivudine treatment for chronic hepatitis B infection in children unresponsive to interferon

BACKGROUND/AIMS: Lamivudine is a potent inhibitor of hepatitis B virus (HBV) replication. This prospective open study reports the results of lamivudine treatment in children with chronic hepatitis B infection who did not respond to previous interferon treatment. PATIENTS AND METHODS: Lamivudine, 3 mg/kg/day (maximum, 100 mg/day), was given for 52 weeks to 20 children and adolescents, ages 8.5 to 19 years, with chronic hepatitis B infection who had been treated with interferon 2 to 5 years earlier. We evaluated virologic and biochemical responses, the occurrence of YMDD mutants and adverse effects. RESULTS: All children were HBV DNA+, hepatitis B e antigen (HBeAg) /anti-hepatitis B e antibody- at start of treatment. At the end of 1 year, HBV DNA declined by 95% in all patients, and 8 of 18 (44%) had sustained undetectable HBV DNA by hybridization assay. Median pretreatment alanine aminotransferase (ALT) x1.5 upper limit of normal decreased to ALT x0.9 upper limit of normal after 1 year. One child became HBeAg-negative. YMDD mutants were detected in 11 of 17 (65%) children after 1 year of lamivudine treatment. Among children with YMDD mutant variants, 54% maintained normal ALT values and 45% had undetectable HBV DNA by hybridization assay. No adverse effects were observed. CONCLUSIONS: Children with chronic hepatitis B infection treated with lamivudine after failure of interferon therapy had decreased HBV replication and improved ALT values. However, lamivudine treatment resulted in an exceptionally high rate of lamivudine-resistant mutants and low HBeAg seroconversion rate.     

Stress-responsive JNK mitogen-activated protein kinase mediates aspirin-induced suppression of B16 melanoma cellular proliferation

1. Available anticancer drugs do not seem to modify the prognosis of metastatic melanoma. Salicylate and acetyl salicylic acid (aspirin) were found to suppress growth in a number of transformed cells, that is, prostate and colon. Therefore, we studied the direct effects of aspirin on metastatic B16 melanoma cells. 2. Aspirin at a plasma-attainable and nontoxic level suppressed the proliferation of B16 cells. 3. Aspirin induced the activation of p38 and c-Jun N-terminal kinase (JNK) mitogen-activated protein kinases. 4. Inhibition of JNK, but not p38, decreased the suppressive effect of aspirin upon the proliferation of B16 cells. 5. The aspirin-induced reduction in B16 proliferation was cumulative over time. 6. Aspirin and the chemotherapeutic drug 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU) induced B16 cell death synergistically. 7. In addition to the murine B16 cell line, the proliferation of SK-28 human melanoma cells was also suppressed by aspirin. 8 In conclusion, aspirin suppresses the proliferation of metastatic B16 cells in a JNK-dependent mechanism.     

Effects of husbands' and wives' education on each other's mortality

Education is an important predictor of one's own cardiovascular disease (CVD) and overall mortality. Little is known, however, regarding the effect of other individuals, specifically a spouse, on these risks. In the present study, we examine the contribution of a spouse's educational attainment and the effect of educational discrepancy between spouses on CVD and overall mortality. Data were taken from the Israel Longitudinal Mortality Study, which linked a 20% sample of the 1983 census to mortality records through 1992. The study cohort comprised 37,618 married couples aged 45-69 years. During the 9.5-year follow-up 6,058 men and 2,568 women died. Overall and CVD mortality hazard ratios were calculated using Cox proportional hazard regression models. We found that the educational attainment of both spouses were significant predictors of one's own overall mortality. For CVD mortality, however, a wife's educational attainment was a stronger predictor of her husband's risk of dying than his own educational level, while for women a husband's education had little affect. Educational discrepancy between partners did not affect overall mortality and had a varied effect on CVD mortality by sex. Specifically, highly educated women had an almost two-fold increased risk of CVD mortality when married to less educated husbands, while lesser-educated women were not affected by their spouses' educational attainment. Spouses' education adds valuable information when assessing mortality differentials among married persons, and socioeconomic characteristics of one's immediate family are important influences on one's health.     

Physical activity and change in body mass index from adolescence to mid-adulthood in the 1958 British cohort

BACKGROUND: Prevention of obesity has focused on childhood as a target period. Our aim was to assess whether frequency of adolescent physical activity affected subsequent body mass index (BMI) gain through to mid-adulthood. METHODS: The British birth cohort of all births in 1 week in March 1958, includes information on physical activity frequency and BMI for several ages, 11-45 years. We examined relationships between activity in adolescence and trajectories of BMI between 16 years (or 23 years) and 45 years using multi-level models. Effects of change in activity on BMI and on change in BMI were tested using ANOVA. RESULTS: Physical activity at 11 years had no effect on the BMI trajectories, in males or females. More active females at 16 years gained BMI more slowly than others, by 0.007 kg/m2/year per activity category over the period 16-45 years, whereas the most active males gained BMI faster than others, by 0.005 kg/m2/year per activity category. This effect in males was not evident on the BMI trajectory from 23 to 45 years. Consistent with these analyses, change in activity was associated with change in BMI in females, e.g. females active at 16 and 42 years gained less BMI than inactive females (2.1 vs 2.5 kg/m2/10 years). Results for males were inconsistent over the time periods examined. CONCLUSIONS: Physical activity may lessen the gains in BMI from adolescence onwards, but relationships vary with age, and in later adolescence show opposite effects for males and females. Decreasing activity between adolescence and mid-adulthood in males, and inactivity in both life stages in females may increase BMI gain.