The PTEN/PI3K pathway governs normal vascular development and tumor angiogenesis

PTEN is an important tumor suppressor gene. Hereditary mutation of PTEN causes tumor-susceptibility diseases such as Cowden disease. We used the Cre-loxP system to generate an endothelial cell-specific mutation of Pten (Tie2CrePten) in mice. Tie2CrePten(flox/+) mice displayed enhanced tumorigenesis due to an increase in angiogenesis driven by vascular growth factors. This effect was partially dependent on the PI3K subunits p85alpha and p110gamma. In vitro, Tie2CrePten(flox/+) endothelial cells showed enhanced proliferation/migration. Tie2CrePten(flox/flox) mice died before embryonic day 11.5 (E11.5) due to bleeding and cardiac failure caused by impaired recruitment of pericytes and vascular smooth muscle cells to blood vessels, and of cardiomyocytes to the endocardium. These phenotypes depend strongly on p110gamma rather than on p85alpha and were associated with decreased expression of Ang-1, VCAM-1, connexin 40, and ephrinB2 but increased expression of Ang-2, VEGF-A, VEGFR1, and VEGFR2. Pten is thus indispensable for normal cardiovascular morphogenesis and post-natal angiogenesis, including tumor angiogenesis.     

Small marker chromosome identification in metaphase and interphase using centromeric multiplex fish (CM-FISH)

Multicolor karyotyping procedures, such as multiplex fluorescence in situ hybridization (M-FISH), spectral karyotyping, or color-changing karyotyping, can be used to detect chromosomal rearrangements and marker chromosomes in prenatal diagnosis, peripheral blood cultures, leukemia, and solid tumors, especially in cases where G-banding is not sufficient. A regular M-FISH analysis requires relatively large amounts of labeled DNA (microgram quantities), is not informative in interphase nuclei, hybridization can take up to 2 to 3 days, and unlabeled human chromosome-painting probes are not available commercially. Unique probes (plasmids, PAC), specific for centromeric or subtelomeric chromosomal regions, can replace the painting probes in M-FISH to address specific issues, such as the identification of marker chromosomes and aneuploidies. A set of plasmid probes carrying repetitive sequences specific for the alpha-satellite region of all human chromosomes were combined in a metaphase assay and an interphase assay, allowing identification of aneuploidies in one hybridization step, on a single cytogenetic slide. The fluorophore-dUTP and the labeled antibodies required to label and detect the DNA probes can be prepared in any laboratory. All DNA probes can be easily isolated and labeled using common molecular cytogenetic procedures. Because of the repetitive nature of the probes, hybridization time is short, usually less than 1 hour, and the analysis can be performed with nonspecialized image-processing software.     

Simultaneous, clonally identical T cell expansion in tonsil and synovium in a patient with rheumatoid arthritis and chronic tonsillitis

In some patients with rheumatoid arthritis (RA), the disease improves following tonsillectomy. We describe a 28-year-old woman with treatment-resistant RA and chronic tonsillitis. Initially, her arthritis had been well controlled with methotrexate and corticosteroids, but the RA activity became difficult to control in spite of addition of bucillamine to the treatment regimen and repeated arthrocentesis with infusion of corticosteroid into her swollen joints. Closer examination revealed that the period of exacerbation of her chronic tonsillitis paralleled that of the systemic arthritis, and administration of antibiotics brought transient relief of the systemic symptoms. Her arthritis was ameliorated after successful tonsillectomy and synovectomy, with marked reduction of the serum rheumatoid factor concentration. Analysis of infiltrating T cell clones in tonsil and synovium using T cell receptor V(beta) repertoire and third complementarity-determining region size distribution analysis followed by nucleotide sequencing revealed common clonal T cell expansion in both tissues. This finding suggests the possible involvement of chronic focal infection in refractory RA.     

Familial aggregation of Behçet's disease in Turkey

OBJECTIVE—Familial aggregation of Behçet''s disease has been reported previously. The current study aimed at investigating the sibling recurrence risk ratio (λs) for Behçet''s disease, which is of value in the estimation of the magnitude of genetic factors in the pathogenesis of Behçet''s disease.
METHODS—170 consecutive unrelated index cases (98 male, 72 female) were interviewed with a detailed questionnaire to ascertain their family trees and the manifestations of Behçet''s disease in their relatives. Subsequently, the immediately older sibling, or if an older sibling was not available, the immediately younger sibling, was selected as the second sibling for the evaluation. These siblings were contacted by telephone, and all subjects with recurrent oral ulcers were invited for examination.
RESULTS— 31 of the 170 index cases had 51 relatives fulfilling the International Study Group criteria. Among 166 second siblings, seven had Behçet''s disease (six male, one female) and 22 siblings (eight male, 14 female) with recurrent oral ulcers were identified. Sibling recurrence rate—defined as the ratio of the risk of being affected among the siblings of patients and the risk of being affected in the general population— was found to be 4.2%, which gives a λs value for Behçet''s disease of between 11.4 and 52.5 in Turkey.
CONCLUSIONS—A high λs value supports a strong genetic background for Behçet''s disease which will be helpful in designing genetic linkage studies.

     

Conventional risk factors and acute coronary syndrome during a period of socioeconomic transition: population-based case-control study in Tirana, Albania

Aim

To assess the association between conventional risk factors and acute coronary syndrome in Albania, a transitional country in Southeast Europe.

Methods

A population-based case-control study was conducted in Tirana in 2003-2006. A total of 467 consecutive patients with nonfatal acute coronary syndrome were recruited. There were 370 men with mean ± standard deviation (SD) age of 59.1 ± 8.7 years and 97 women with mean±SD age of 63.3 ± 7.1 years. The control group comprised a population-representative sample of Tirana residents. In the control group, there were 469 men with mean±SD age of 53.1 ± 10.4 years and 268 women aged 54.0 ± 10.9 years. A structured questionnaire on demographic, socioeconomic, psychosocial factors, and health behaviors was administered. Physical measurements included anthropometrics and blood pressure. Venous blood and adipose tissue aspirations from the gluteal region were frozen-stored for future analysis. Multivariable-adjusted logistic regression was used to assess the independent associations of conventional risk factors with acute coronary syndrome.

Results

Upon adjustment for covariates, family history of coronary heart disease was found to be a strong predictor of acute coronary syndrome in both men (odds ratio [OR], 3.70; 95% confidence interval [CI], 2.58-5.30) and women (OR, 4.53; 2.40-8.57). Waist-to-hip ratio in men (OR, 4.03; 2.83-5.73) and obesity in women (OR, 3.31; 1.54-7.14) were strongly associated with acute coronary syndrome. In men, but not in women, there was a significant association with hypertension and current smoking (P = 0.011 and P<0.001, respectively). Diabetes was not significantly independently associated in either sex.

Conclusion

Classical risk factors predicted coronary heart disease in Albania, similarly as in the rest of the world, although associations with family history and anthropometric indices were stronger. These findings are resulting largely from the heterogeneous adoption of lifestyles conducive to increased coronary risk in transitional countries, and they point to the urgent need for targeted public health interventions.The relationship between coronary heart disease and risk factors such as smoking, high blood pressure, diabetes, obesity, and distribution of body fat is well established in developed countries (1-4). However, data on conventional risk factors, their patterns, determinants, and associations with coronary heart disease are scarce for the transitional countries of South East Europe. Unique among former communist countries in Southeast Europe, Albania was under Stalinist communist regime, and following the breakdown of this rigid government in 1990, it experienced a major social, cultural, and economic upheaval (5). Over the past 15 years changes in life-style (diet, tobacco, alcohol consumption, and physical exercise) have taken place, particularly in urban settings (6-8). The available evidence suggests an increase in alcohol intake, particularly among men (6). Smoking appears to have increased too, although smuggling makes it very difficult to validly estimate cigarette consumption in Albania (7). In 2001, the lifetime prevalence of smoking in Tirana was 61% in men and 24% in women (8). Furthermore, in 2001, 49% of men and 58% of women in Tirana reported largely sedentary leisure time activities such as reading and watching television (9). Although there is little information about cardiovascular disease occurrence in Albania, available data suggest that cardiovascular disease mortality may have increased over the past few years (10,11), and that cardiovascular disease morbidity (based on hospital admission counts) in both Tirana and the whole country has been increasing continually in the last decade (10).In this context, we undertook a population-based case-control study of coronary heart disease in Tirana between June 2003 and January 2006. Here, we report on the association of selected conventional risk factors such as smoking, anthropometric indices, hypertension, diabetes, and family history of coronary heart disease with acute coronary syndrome.     

The effects of one- and two-stage orchiopexy on postoperative serum testosterone levels and testicular volume in adult patients with bilateral nonpalpable testes

In this study, we investigated the effects of one- and two-staged orchiopexy on testicular volume and serum testosterone levels in cases with high, abdominally localized, bilateral nonpalpable testes. Between March 1996 and April 2001, orchiopexy was performed on 46 testes in 23 patients with bilateral nonpalpable testes. In 15 of the 23 patients, a two-stage Fowler-Stephens orchiopexy was performed, and in 8 of the 23 patients, a one-stage laparoscopic orchiopexy was performed. For one patient who lacked both testes, bilateral prosthetic testes were inserted. The patients' ages were between 20 and 23 years (average, 21 years). In the first stage of the two-stage orchiopexy, the spermatic artery was ligated laparoscopically. Six months later, open surgery orchiopexy was performed. Patients were followed for 2 to 16 months (average, 10 months) and were evaluated for testicular atrophy, serum testosterone levels, and complications. In all the patients, the preoperative secondary sexual characteristics and serum testosterone levels were normal. Among the postoperative controls, evaluated at months 3 and 6, one patient's testes were found at the pubic area. Testicular atrophy was not observed in any of the patients, and the serum testosterone levels were in the normal range. In the two-stage orchiopexy group, 5 (33%) of the 15 patients had an average 30% volume decrease, and in the one-stage group, 2 (25%) of the 8 patients had an average 40% volume decrease. In this study, it was shown that either two-stage Fowler-Stephens orchiopexy or laparoscopic orchiopexy can be successfully performed in patients with bilateral abdominal testes, and that the testes can be fixed to their palpable original positions without interfering with the secretion of testosterone. Although the results are similar, our experience suggests that single-stage laparoscopic orchiopexy is the preferable method.     

Endotoxaemia in severe burns

In an attempt to detect endotoxaemia the authors carried out the Limulus test in burned patients' plasma. The test was positive mainly in lethal cases, yet it was negative in many other cases where endotoxaemia could be presumed.The authors therefore carried out a series of experiments in rabbits, in which they proved that endotoxin entering the circulation is being accumulated in leucocytes and can be detected in platelet-leucocyte lysate, using Limulus test, even at low concentrations, when Limulus test in plasma is negative.It appears that endotoxin detection by Limulus test in plasma does not offer decisive results and that it should be supplemented by endotoxin detection in platelet-leucocyte lysate.     

Lamivudine monotherapy in children with immune-tolerant chronic hepatitis B virus

We investigated the efficacy of lamivudine treatment in inducing a primary and sustained response in naive pediatric patients with immune-tolerant chronic hepatitis B viral (HBV) infection. Lamivudine was used (maximum 100 mg/day) for an average of 35 months (16-60 months) for 17 patients, while 6 patients were untreated. All the treated patients became HBV-DNA negative in the twelfth month of therapy with an average of 7 months, however none of them had a sustained virological response. They all became HBV-DNA positive by the twentieth month on average. One patient had significant improvement in liver histology. No side effects were observed. Spontaneous HBV-DNA clearance or HBe seroconversion was obtained in none of the untreated cases. This study suggests that lamivudine cannot induce complete viral control in HBV pediatric immune-tolerant patients.