H-RAS 81 polymorphism is significantly associated with aneuploidy in follicular tumors of the thyroid

Follicular thyroid tumors are often aneuploid. It was advanced that chromosomal instability is closely associated to RAS mutations, but such association remains unproven. H-RAS can be alternatively spliced in two different proteins, p21 and p19, the former being the active protein. In order to investigate the relationship between RAS mutational status and ploidy in thyroid tumors, we analysed RAS genes in a series of 99 follicular lesions (14 nodular goiters, 70 follicular adenomas and 15 follicular carcinomas), eight thyroid carcinoma cell lines and a control group of 102 blood donors, correlating the presence of RAS mutations with the ploidy of the tumors and evaluating the two spliced forms of H-RAS. Overall, 20% of the follicular tumors harbored RAS mutations and 62% of the patients with follicular tumors (and 51% of blood donors) harbored the H-RAS 81T --> C polymorphism. The presence of RAS mutations was not associated with aneuploidy. The H-RAS polymorphism did not seem to confer a higher propensity for neoplastic transformation as it was also found in hyperplastic lesions, but was strongly associated with aneuploidy (P<0.0001). The presence of the H-RAS 81T --> C polymorphism was associated with significantly higher amounts of total H-RAS mRNA expression, higher amounts of p21 isoform and a higher fraction of neoplastic cells in S phase. Our results suggest that the H-RAS 81T --> C polymorphism may induce aneuploidy through overexpression of the active p21 isoform of H-RAS.

[Bronchodilators in acute asthma: metered dose inhalers or wet nebulizations?]

of patients attending our Emergency Department (ED) with acute asthma has increased from 3300 patient/year in 1980 to 15364 in 2003. Short acting bronchodilators (albuterol/ipratropium) administered in wet nebulizations, a resource consuming procedure, were our main initial treatment in 2002. To improve treatment goals, we switched the method of bronchodilator delivery to metered dose inhalers (MDI) in 2003. The purpose of this study is to evaluate the impact of this change in the bronchodilator delivery system. We compared 90 patients with acute asthma treated with MDIs in December 2003 with a similar number treated with wet nebulizers in December 2002 matched for sex, age, height, and FEV1 on admission. Treated with MDIs resulted in significant reduction of length of stay in the ED (median 3 vs 4 hs--quartiles 2-4.75 vs. 1-6 hs, p = 0.01) and an increase in the number of discharges in the first 2 hours of treatment (48 vs. 31% p = 0.03). Overall, patients in the MDI's group received 87% of the scheduled bronchodilator doses, while patients in the wet nebulizer's group received only 37% of the prescribed doses. Although there was a trend towards better FEV1 at discharge in the MDI's group, the difference was not statistically significant (78% +/- 17% vs. 73% + 17% p = 0.09). Percentage of patients finally discharged from the ED was similar in both groups (96 vs 94%). Patients treated with bronchodilators delivered by MDI improved faster and had better fulfillment of treatment standards.

PAX8-PPARgamma rearrangement is frequently detected in the follicular variant of papillary thyroid carcinoma

CONTEXT

The clinicopathological characteristics and the molecular features of the follicular variant of papillary thyroid carcinoma (FVPTC) remain controversial.

OBJECTIVE/DESIGN/PATIENTS

In an attempt to clarify such controversies and to find whether or not FVPTC cases share the molecular features of follicular tumors, we searched for the presence of PAX8-PPARgamma rearrangements, RAS mutations, and RAP-1, RAF-1, and BRAF mutations in a series of 40 FVPTCs as well as in 27 follicular thyroid carcinomas (FTCs) and 12 follicular thyroid adenomas (FTAs). Fluorescence in situ hybridization and RT-PCR were used to detect the PAX8-PPARgamma rearrangement and PCR, single strand confirmational polymorphism, and sequencing for searching the mutations.

RESULTS

The frequency of PAX8-PPARgamma rearrangement was similar in FVPTCs (37.5%), FTCs (45.5%), and FTAs (33.3%). The same holds true regarding the frequency and type of RAS mutations: FVPTC, 25.0%; FTC, 22.2%; and FTA, 33.3%. BRAF mutations were only detected in FVPTC (10%); the BRAF mutations in these cases (K601E and G474R) are different from the typical BRAF(V600E) mutation of conventional PTCs. No mutations were detected in RAP-1 and RAF-1. In FVPTCs, the PAX8-PPARgamma rearrangement was significantly associated with multifocality and vascular invasion, whereas the RAS mutations were significantly associated with the large tumor size. There were three cases of FVPTC, three FTCs and one FTA, harboring both PAX8-PPARgamma rearrangement and RAS mutations; patients with such tumors were usually very young.

CONCLUSIONS

We conclude that a subset of FVPTC shares some of the molecular features of follicular tumors. Further studies are necessary to clarify the putative clinical significance (e.g. association to blood-born metastases) of PAX8-PPARgamma rearrangement, RAS mutations, and BRAF(K601E) in FVPTCs.

Linezolid treatment of ventriculoperitoneal shunt infection without implant removal

Ventriculoperitoneal shunt infection is a serious clinical problem for which implant removal is considered the treatment of choice. However, surgery is sometimes associated with considerable risks that may outweigh the benefits. Presented here is a case of ventriculoperitoneal shunt infection treated successfully with linezolid without implant removal. This case shows linezolid could be a therapeutic alternative when surgery is contraindicated.

Risk of selecting de novo drug-resistance mutations during structured treatment interruptions in patients with chronic HIV infection

BACKGROUND

Structured treatment interruption (STI) may allow viral replication in the presence of decreased plasma drug levels, with risk of selection of resistance mutations.

METHODS

For patients recruited for an STI study, genotypic resistance testing was performed at baseline (before receipt of any treatment), immediately before the STI, and 2 weeks after each interuption of therapy.

RESULTS

During 20 (18%) of 112 STI cycles (95% CI, 11%-26%), resistance mutations were selected; 6% of the mutations were de novo (i.e., not detected before the start of STI), and 12% were archived mutations (i.e., mutations already detected before the STI). Overall, resistance mutations during STI were selected in 9 (26%) of 35 patients; 5 (14%) of the mutations were de novo, and 4 (12%) were archived mutations. Mutations conferring resistance to nonnucleoside reverse-transcriptase inhibitors (NNRTIs) were selected in 3 (23%) of 13 patients receiving NNRTI-based regimens (all mutations were de novo). Mutations conferring resistance to lamivudine were selected in 9 (50%) of 18 patients receiving lamivudine-containing regimens (4 [22%] were de novo, and 5 [28%] were archived mutations). Mutations conferring resistance to nucleoside reverse-transcriptase inhibitors (NRTIs), excluding the M184V mutation, were selected in 2 (6%) of 35 recipients of NRTIs (1 [3%] of these mutations was de novo, and 1 [3%] was an archived mutation. Finally, mutations conferring resistance to protease inhibitors were selected in none of the 22 patients receiving protease inhibitors. In most cases, de novo and archived mutations were selected during the first STI cycle, and their number did not increase during successive cycles. Plasma viral load decreased to undetectable levels in all the patients when the earlier drug regimen was reintroduced.

CONCLUSIONS

Genotypic mutations are selected during STI in a high proportion of patients (especially in patients receiving NNRTIs or lamivudine). Approximately one-half of selected mutations were archived mutations. Patients who had archived mutations did not have a higher risk of accumulating new mutations than did patients who were infected with wild-type virus before the STI.

Influence of interleukin-10 genetic polymorphism on survival rates in melanoma patients with advanced disease

Individual ability to produce interleukin-10 (IL-10) may be of relevance in the development and evolution of cutaneous melanoma, probably due to its immunosuppressor and anti-angiogenic properties. Single nucleotide polymorphisms at positions -1082 (G/A), -819 (C/T) and -592 (C/A) in the IL-10 gene promoter were analysed in 100 healthy individuals and 98 melanoma patients using fluorogenic hybridization-specific probes in a 'real-time' thermocycler. Polymorphic frequencies were correlated with various prognostic factors and overall survival. The frequency of IL-10 polymorphic variants was similar in patients and controls. However, high producer genotypes at the -1082 position were over-represented in males with an older age at diagnosis. The analysis of the promoter genotypes in patients stratified according to clinical prognostic factors did not show any associations, although a trend (not statistically significant) towards a prolonged survival in patients genotyped as high IL-10 producers was observed. In addition, the low producer -1082AA genotype was significantly associated with decreased survival in patients with advanced disease. Similarly, the presence of this genotype shortened the overall survival in males after recurrence or metastasis development. In conclusion, the frequency of genetic variants in the IL-10 gene promoter was not associated with melanoma appearance, but conditioned the age at diagnosis in males and the overall survival in patients with advanced disease.

Life-threatening isopropyl alcohol intoxication: is hemodialysis really necessary?

Isopropyl alcohol (IPA) is widely used in industrial and home-cleaning products, easily available to general public and inexpensive: intoxications can occur unintentionally, in suicide attempts or by alcohol abusers as a substitute for ethanol. Symptoms involve the gastrointestinal tract, central nervous system and at high doses cardiovascular manifestations may appear. Ketonemia, ketonuria without hyperglicemia or acidosis and elevated osmol gap are common laboratory findings. Mortality and morbidity is low, but some fatal cases have been reported in patients in deep coma and especially those with hypotension. We present a life-threatening intoxication, with deep coma and hypotension, treated successfully with hemodialysis. Whether hemodialysis must always be performed is a controversial question. Our opinion is hemodialysis is not needed, even in life-threatening situations. Arguments about this opinion are presented.

The expression of Sprouty1, an inhibitor of fibroblast growth factor signal transduction, is decreased in human prostate cancer

A considerable body of evidence indicates that alterations of fibroblast growth factors (FGFs) and their receptors contribute to prostate cancer progression. Recently, a new family of regulators of FGF activity has been identified. The Sprouty gene family negatively regulates FGF signaling in a variety of systems and could potentially limit the biological activity of FGFs in prostate cancer. Immunohistochemical analysis of normal and neoplastic prostate tissues using tissue microarrays revealed that Sprouty1 protein is down-regulated in approximately 40% of prostate cancers when compared with matched normal prostate. By quantitative real-time PCR analysis, we found that Sprouty1 mRNA levels were significantly decreased in prostate cancers in vivo in comparison with normal prostate. In prostate cancer cell lines, there is loss of the normal up-regulation of Sprouty1 mRNA and protein in response to FGFs. The decrease in Sprouty1 expression in the human prostate cancer, despite elevated levels of FGF ligands and FGF receptors, implies a loss of an important growth regulatory mechanism in prostate cancers that may potentiate the effects of increased FGF and FGF receptor expression in prostate cancer.

Interleukin-8 expression is increased in senescent prostatic epithelial cells and promotes the development of benign prostatic hyperplasia

BACKGROUND

Benign prostatic hyperplasia (BPH) is an extremely common disease of older men characterized by increased growth of prostatic epithelial and stromal cells. Previously we showed that senescent epithelial cells accumulate in the prostate of aging men and secrete interleukin-1 alpha (IL-1 alpha). IL-8 is also present at increased levels in BPH tissues and induces expression of FGF2, a potent stromal growth factor. Therefore, we sought to determine if IL-8 is also expressed at increased levels by senescent epithelial cells and if this secreted IL-8 plays a role in the pathogenesis of BPH.

METHODS

Expression of IL-8 in human BPH tissue and primary cultures of prostatic epithelial cells was analyzed using an enzyme-linked immunoabsorption assay (ELISA). Tissue senescence was assessed by a quantitative assay for senescence-associated beta galactosidase (SA-beta gal). Proliferation of primary and immortalized prostatic epithelial cells in response to IL-8 was determined by counting of cells at intervals after addition of IL-8.

RESULTS

Expression of IL-8 is significantly increased in vitro when cultured prostatic epithelial cells undergo senescence. Quantitative assay of BPH tissue extracts revealed that tissue IL-8 levels are correlated with both SA-beta gal activity and prostate weight. IL-8 promotes proliferation of primary and immortalized prostatic epithelial cells in culture.

CONCLUSIONS

Senescence of prostatic epithelial cells results in increased expression of IL-8, which can promote proliferation of non-senescent epithelial and stromal cells by direct and indirect mechanisms, and in this manner contributes to the increased tissue growth seen in BPH.

Cellular senescence in the pathogenesis of benign prostatic hyperplasia

BACKGROUND

Senescent cells accumulate in tissues with age and show changes in protein expression that may influence the function of adjacent cells and contribute to the development of tissue pathologies associated with aging. Benign prostatic hyperplasia (BPH) is an extremely common disease of older men characterized by increased growth of prostatic epithelial and stromal cells. In BPH, there is an increased expression of Il-1alpha by prostatic epithelial cells that results in elevated expression of FGF7 by stromal cells, which in turn is strongly correlated with epithelial proliferation.

METHODS

Human BPH tissue and primary cultures of prostatic epithelial cells were analyzed by histochemical and quantitative assays for senescence-associated beta galactosidase (SA-beta gal). Il-1alpha expression was localized by immunohistochemistry and Il-1alpha tissue content determined by enzyme-linked immunoabsorption assay.

RESULTS

Expression of Il-1alpha is significantly increased in vitro when cultured prostatic epithelial cells undergo senescence. In BPH tissue a substantial population of epithelial cells express senescence-associated beta galactosidase (SA-beta gal), a marker of cellular senescence. By quantitative assay, SA-beta gal activity is correlated with both tissue levels of Il-1alpha and the severity of BPH.

CONCLUSIONS

One mechanism driving BPH in older men is the accumulation of senescent epithelial cells expressing Il-1alpha, which in turn increases FGF7 secretion and proliferation of non-senescent epithelial cells. Thus there is a mechanistic linkage between cellular senescence and one of the most common pathologies of older men.

Interindividual variations in constitutive interleukin-10 messenger RNA and protein levels and their association with genetic polymorphisms

BACKGROUND

Genetic variations in the interleukin (IL)-10 gene promoter have been associated with levels of induced production of IL-10, disease susceptibility, and allograft rejection. Small amounts of this cytokine are constitutively produced and are important in maintaining the physiologic function of the cytokine network. In this study, we evaluated the distribution of IL-10 basal levels and its genetic regulation in a healthy Spanish population.

METHODS

Polymorphisms at the -1,082, -819, and -512 positions of the IL-10 promoter were analyzed by polymerase chain reaction amplification and hybridization with fluorescent-labeled allele-specific probes in 183 Spanish people. Levels of IL-10 messenger (m)RNA were tested by real-time reverse transcription-polymerase chain reaction in 123 healthy donors. Serum concentrations of IL-10 were measured by a highly sensitive ELISA, whereas protein amounts in lipopolysaccharide culture supernatants were quantified by an in-house ELISA.

RESULTS

The frequency of IL-10 promoter alleles and haplotypes in our population showed remarkable differences from other Caucasian populations. Large interindividual variations were found in mRNA and protein constitutive levels of IL-10, which allowed its classification in low and intermediate/high producers. We found statistical differences in mRNA concentration between the polymorphic variant GCC/GCC and the low producer genotypes. The G allele at position -1082 was the most important genetic factor in the regulation of constitutive IL-10 mRNA levels. Similarly, we also found an association of this polymorphic position with serum concentration greater than 2 pg/mL.

CONCLUSIONS

Constitutive levels of IL-10 (mRNA and serum protein) displayed remarkable interindividual variations, which are genetically controlled by polymorphic variants at the cytokine gene promoter.

A novel, evolutionarily conserved gene family with putative sequence-specific single-stranded DNA-binding activity

Complete and partial deletions of chromosome 5q are recurrent cytogenetic anomalies associated with aggressive myeloid malignancies. Earlier, we identified an approximately 1.5-Mb region of loss at 5q13.3 between the loci D5S672 and D5S620 in primary leukemic blasts. A leukemic cell line, ML3, is diploid for all of chromosome 5, except for an inversion-coupled translocation within the D5S672-D5S620 interval. Here, we report the development of a bacterial artificial chromosome (BAC) contig to define the breakpoint and the identification of a novel gene SSBP2, the target of disruption in ML3 cells. A preliminary evaluation of SSBP2 as a tumor suppressor gene in primary leukemic blasts and cell lines suggests that the remaining allele does not undergo intragenic mutations. SSBP2 is one of three members of a closely related, evolutionarily conserved, and ubiquitously expressed gene family. SSBP3 is the human ortholog of a chicken gene, CSDP, that encodes a sequence-specific single-stranded DNA-binding protein. SSBP3 localizes to chromosome 1p31.3, and the third member, SSBP4, maps to chromosome 19p13.1. Chromosomal localization and the putative single-stranded DNA-binding activity suggest that all three members of this family are capable of potential tumor suppressor activity by gene dosage or other epigenetic mechanisms.

Generation of GW radiation pulses from a VUV free-electron laser operating in the femtosecond regime

Experimental results are presented from vacuum-ultraviolet free-electron laser (FEL) operating in the self-amplified spontaneous emission (SASE) mode. The generation of ultrashort radiation pulses became possible due to specific tailoring of the bunch charge distribution. A complete characterization of the linear and nonlinear modes of the SASE FEL operation was performed. At saturation the FEL produces ultrashort pulses (30-100 fs FWHM) with a peak radiation power in the GW level and with full transverse coherence. The wavelength was tuned in the range of 95-105 nm.

Blood pressure response in 24 hours in patients with high blood pressure treated with two nifedipine formulations once a day

A double-blind, comparative and prospective study with nifedipine once a day was undertaken, in patients with mild and moderate high blood pressure. Blood pressure was measured by mercury sphygmomanometer in two positions: resting and sitting at 3, 6 and 12 weeks of treatment and by ambulatory blood pressure monitoring (ABPM) over 24 h; both were carried out before and after the treatment and the uniformity in the pressure levels were obtained by means of the Smoothness Index. Fifty-four patients were included in the trial, 28 in the microgranules group and 26 in the osmotic pump group. These groups were similar at the baseline in age, gender, weight, height, diastolic and systolic blood pressure. The nifedipine microgranules group had a heart rate higher than the nifedipine osmotic pump group at baseline (X(M) = 75.58 vs. X(B) = 70.75). Blood pressure decreased significantly during the first 3 weeks; 85% in the microgranules group and 75% in the osmotic pump group reached a blood pressure < or =140/90 mm Hg at the end of the study. Three patients in the microgranules group and two in the osmotic pump group required an additional antihypertensive drug. In both groups, the average blood pressure over 24 h was lowered without differences between groups. A decrease was induced in the heart rate in both groups which reached a marginal statistical significance in the microgranules nifedipine group. No changes were induced in the laboratory tests; two patients in the microgranules (8%) nifedipine group and five in the nifedipine osmotic pump group, adverse effects were observed, of which only one in each group required stopping the treatment.