Effects of education level and employment status on HRQoL in early relapsing-remitting multiple sclerosis

Purpose To evaluate the effects of education level and employment status on health-related quality of life (HRQoL) in a large cohort of patients affected by relapsing-remitting multiple sclerosis (RRMS). Patients This study included 648 patients with RRMS attending 40 Italian MS centers. Inclusion criteria were an Expanded Disability Status Scale (EDSS) score between 1.0 and 5.5; stable disease on enrollment; and no previous treatment with interferons, glatiramer acetate, or immunosuppressive drugs. Quality of life (QoL) was evaluated by the Multiple Sclerosis Quality of Life-54 questionnaire (MSQoL-54).

Results Employed patients scored significantly higher than other patient groups in the majority of MSQoL-54 domains. Similarly, patients with academic degrees and secondary education had higher scores than those with primary education (ie, eight years of education) in several domains of HRQoL. Patients who were employed with a high educational level achieved significantly better scores than unemployed patients with a lower educational level. In multivariate analysis, occupation and educational level were found to be significant and independent predictors of HRQoL.

Conclusions The results of our study suggest the importance of sustaining employment after a recent diagnosis of MS. In addition, education has a great influence on HRQoL; a higher education level may determine a stronger awareness of the disease, and a better ability to cope with the challenges of a chronic disease such as MS. Multiple Sclerosis 2007; 13: 783-791. http://msj.sagepub.com

Genes expressed during the development and ripening of watermelon fruit

A normalized cDNA library was constructed using watermelon flesh mRNA from three distinct developmental time-points and was subtracted by hybridization with leaf cDNA. Random cDNA clones of the watermelon flesh subtraction library were sequenced from the 5' end in order to identify potentially informative genes associated with fruit setting, development, and ripening. One-thousand and forty-six 5'-end sequences (expressed sequence tags; ESTs) were assembled into 832 non-redundant sequences, designated as "EST-unigenes". Of these 832 "EST-unigenes", 254 ( approximately 30%) have no significant homology to sequences published so far for other plant species. Additionally, 168 "EST-unigenes" ( approximately 20%) correspond to genes with unknown function, whereas 410 "EST-unigenes" ( approximately 50%) correspond to genes with known function in other plant species. These "EST-unigenes" are mainly associated with metabolism, membrane transport, cytoskeleton synthesis and structure, cell wall formation and cell division, signal transduction, nucleic acid binding and transcription factors, defense and stress response, and secondary metabolism. This study provides the scientific community with novel genetic information for watermelon as well as an expanded pool of genes associated with fruit development in watermelon. These genes will be useful targets in future genetic and functional genomic studies of watermelon and its development.

TLQP-21, a VGF-derived peptide, increases energy expenditure and prevents the early phase of diet-induced obesity

The vgf gene has been identified as an energy homeostasis regulator. Vgf encodes a 617-aa precursor protein that is processed to yield an incompletely characterized panel of neuropeptides. Until now, it was an unproved assumption that VGF-derived peptides could regulate metabolism. Here, a VGF peptide designated TLQP-21 was identified in rat brain extracts by means of immunoprecipitation, microcapillary liquid chromatography-tandem MS, and database searching algorithms. Chronic intracerebroventricular (i.c.v.) injection of TLQP-21 (15 mug/day for 14 days) increased resting energy expenditure (EE) and rectal temperature in mice. These effects were paralleled by increased epinephrine and up-regulation of brown adipose tissue beta2-AR (beta2 adrenergic receptor) and white adipose tissue (WAT) PPAR-delta (peroxisome proliferator-activated receptor delta), beta3-AR, and UCP1 (uncoupling protein 1) mRNAs and were independent of locomotor activity and thyroid hormones. Hypothalamic gene expression of orexigenic and anorexigenic neuropeptides was unchanged. Furthermore, in mice that were fed a high-fat diet for 14 days, TLQP-21 prevented the increase in body and WAT weight as well as hormonal changes that are associated with a high-fat regimen. Biochemical and molecular analyses suggest that TLQP-21 exerts its effects by stimulating autonomic activation of adrenal medulla and adipose tissues. In conclusion, we present here the identification in the CNS of a previously uncharacterized VGF-derived peptide and prove that its chronic i.c.v. infusion effected an increase in EE and limited the early phase of diet-induced obesity.

Construction of a watermelon BAC library and identification of SSRs anchored to melon or Arabidopsis genomes

A bacterial artificial chromosome (BAC) library was constructed for watermelon (Citrullus lanatus (Thunb.) Matsum. & Nakai var. lanatus) with an average insert-size of 106 kb, providing 21 haploid genome equivalents. The library was used to identify BAC clones that are anchored to probes evenly distributed on the genomes of melon or Arabidopsis. Twenty eight probes (representing 66% of the tested probes) from melon and 30 probes (65%) from Arabidopsis identified positive BAC clones. Two methods were implemented to identify SSRs from the positively hybridizing BAC clones. First, analysis of BAC end sequences revealed 37 SSRs. For the second method, pooled DNA of BACs identified by the melon probes was used to develop a shotgun library. The library was then screened with synthetic SSR oligonucleotides by hybridization. Sequence analysis of positively hybridizing shotgun clones revealed 142 different SSRs. Thirty eight SSRs were characterized using three watermelon cultivars, five plant introduction (PI) accessions of C. lanatus var lanatus and four PIs of C. lanatus var citroides. Of these, 36 (95%) were found to be polymorphic with up to six alleles per marker. Polymorphism information content values for polymorphic markers varied between 0.22 and 0.79 with an average of 0.53. The methods described herein will be valuable for the construction of a watermelon linkage map with SSRs evenly distributed on its genome that is anchored to the genomes of melon and Arabidopsis.

[Therapeutic advances in neoplastic hematology: target therapy anti-CD33]

Antibodies capable to recognize antigen expressed on cancer cells represents the ideal approach for targeted anti neoplastic therapies. The CD33 antigen is present on 90% of acute myeloid leukemia blasts and is shared on normal hemopoietic cells only on the non stem dillerentiating fraction. Gemtuzumab Ozogamicin (GO) is an engineered humanized antibody anti-CD33 conjugated with a potent intercalating agent, named calicheamicin, which is release only at intracellular level (lower pH), following a selective binding to CD33-positive cells, thus representing a promising approach for target anti-leukemia therapy. GO was approved conditionally by the Federal Drug Administration in May 2000 as a single therapy for first recurrence of Acute Myeloid Leukemia (AML) in a subset of older patients. Since 2000, treatment trials and pilot studies have revealed potential expanded applications along with potential limitations. Phase II trials have confirmed the activity and the efficacy of GO as single agent in the treatment of relapsed AML. More recently, clinical trials on induction and post-remission treatment of adult AML have shown efficacy of GO in combination chemotherapy. The strong and homogeneous CD33 expression in Acute Promyelocytic Leukemia (APL), have resulted in an effective treatment of this disease with GO used as salvage treatment, as well as innovative approach for molecular relapsed patients. However, the incidence of veno-occlusive disease, better defined as sinusoidal occlusive syndrome (SOS), must be taken into account as potential complication associated with the GO administration, especially in patients treated with ablative regimens. In conclusion, the extension of the approval in Italy to AML CD33+ in relapsed, regardless age limitation, along with the ongoing evaluation by the European EMEA, represent the basis for a large clinical application of GO in myeloid malignancies potentially extended to paediatric patients with AML and to ALL CD33+.

Fine mapping of a schizophrenia susceptibility locus at chromosome 6q23: increased evidence for linkage and reduced linkage interval

We previously reported an autosomal scan for schizophrenia susceptibility loci in a systematically recruited sample of Arab Israeli families. The scan detected significant evidence for linkage at chromosome 6q23 with a nonparametric LOD score (NPL) of 4.60 (P=0.000004) and a multipoint parametric LOD score of 4.16. In order to refine this finding we typed 42 additional microsatellite markers on chromosome 6q between D6S1570 (99.01 cM from the pter) and D6S281 (190.14 from the pter) in the same sample (average intermarker distance approximately 1.7 cM). In the 23 cM region between D6S1715 and D6S311, markers were more closely spaced ( approximately 1.1 cM). Multipoint nonparametric and parametric and single point linkage analyses were performed. The peak NPL rose to 4.98 (P=0.00000058) at D6S1626 (136.97 cM), immediately adjacent to D6S292 (NPL 4.98, P=0.00000068), the marker that gave the highest NPL in the original genome scan, under the broad diagnostic category. The putative susceptibility region (NPL-1) was reduced from 12.0 to 4.96 cM. The peak multipoint parametric LOD score was 4.63 at D6S1626 under a dominant genetic model, core diagnostic category and the LOD-1 interval was 2.10 cM. The maximum single point LOD score (3.55, theta=0.01) was also at D6S1626 (dominant model, core diagnostic category). Increased evidence for linkage in the same sample as in the original genome scan and consistent localization of the linkage peak add further support for the presence of a schizophrenia susceptibility locus at chromosome 6q23. Moreover, the markedly reduced linkage interval greatly improves prospects for identifying a schizophrenia susceptibility gene within the implicated region.

Prevention of heterotopic ossification after spinal cord injury with COX-2 selective inhibitor (rofecoxib)

STUDY DESIGN

A randomized, prospective, double-blind, placebo-controlled clinical trial.

OBJECTIVES

To determine the effect of COX-2-selective inhibitor on the prevention of heterotopic ossification (HO) after spinal cord injury (SCI).

SETTING

County and University Teaching Hospital, Miami, FL, USA.

METHODS

A total of 76 patients were enrolled in the study. Among them, 39 patients received placebo, and 37 received COX-2-selective inhibitor rofecoxib 25 mg daily for a period of 4 weeks. Prevention was started 3 weeks after spinal cord injury (SCI). In both groups of patients there was similar age as well as the level of SCI and ASIA impairment scale. Two methods were used to diagnose early HO, clinical symptoms and bone scintigraphy. Radiography was used for diagnosis of late stages of HO development.

RESULTS

A significantly lower incidence of HO was found in the rofecoxib group (13.4%) than in the placebo group (33.3%: P<0.05). In patients receiving rofecoxib, there was a 2.5 times lower relative risk of developing HO than in the placebo group (95% CI, 2.3-6). There were no patients who discontinued the study due to adverse effects of medication.

CONCLUSION

Our data suggest that COX-2-selective inhibitor rofecoxib is an effective medication in prevention of HO after SCI.

Virulence ofStreptococcus pneumoniaemay be determined independently of capsular polysaccharide

Mice were inoculated intranasally with Streptococcus pneumoniae isolates of serotype 14 with different genetic backgrounds (14R, 14DW) and a capsular switch of 14R, strain 9VR (serotype 9V). Inoculation of the mice with 14R and 9VR resulted in 60% mortality. All the mice survived 14DW inoculation. No differences in lungs' bacterial loads were found 3 h following inoculation. Bacterial clearance of 5 logs was observed 48 h after inoculation with 14DW versus within 1 log 48 h after inoculation with 14R and 9VR. No significant differences in bacterial size or the capsular amount could be found between 14R and 14DW. We conclude that factor(s) in addition to the capsule, contribute to disease outcome.

Differential activation of the immune system by virulent Streptococcus pneumoniae strains determines recovery or death of the host

Streptococcus pneumoniae infection may result in asymptomatic carriage, mucosal or invasive disease. We hypothesize that self-limiting or fatal disease outcome follows infection with S. pneumoniae differential activation of the host immune response. BALB/c and C57BL/6 mice were inoculated intranasally with S. pneumoniae serotype 3 strain WU2 and serotype 14 strain DW14 and mortality, bacterial load, pathological changes in the lungs and cytokines mRNA levels in the spleen were analysed. No differences between the C57BL/6 and the BALB/c inbred mice were observed except for the severity of their lung pathology and IL-4 expression. Infection of the two mouse strains with S. pneumoniae WU2 resulted in sepsis and death that occurred within 4 days post-inoculation. This death was preceded, in both mouse strains, in an increase over time of the lung bacterial load and bacteraemia. The lung pathology was characterized by diffuse pneumonia with marked congestion of the lungs. Analysis of mRNA expression of cytokines in the spleen revealed no alterations in tumour necrosis factor (TNF)-alpha, transforming growth factor (TGF)-beta, interleukin (IL)-12 and interferon (IFN)-gamma and induction of IL-10 and IL-4. The two strains of mice survived infection with S. pneumoniae DW14. This was accompanied by a reduction over time of lung bacterial load and bacteraemia. The lung pathology was characterized by focal lymphocyte infiltration and preserved architecture of the organ. Analysis of mRNA expression of cytokines in the spleen revealed a significant decrease in the levels of TNF-alpha, TGF-beta, IL-12 and IFN-gamma mRNA expression, which usually precedes cytokine protein expression. Interestingly, a significant increase in the levels of IL-4 mRNA expression was found in BALB/c mice only. This study suggests that differential activation or evasion of cytokine expression by S. pneumoniae virulent strains determines disease outcome regardless of the host's immunogenetic background.

A genetic linkage map for watermelon derived from a testcross population: ( Citrullus lanatus var. citroides x C. lanatus var. lanatus) x Citrullus colocynthis

A genetic linkage map was constructed for watermelon using a testcross population [Plant Accession Griffin 14113 ( Citrullus lanatus var. citroides) x New Hampshire Midget (NHM; C. lanatus var. lanatus)] x U.S. Plant Introduction (PI) 386015 ( Citrullus colocynthis). The map contains 141 randomly amplified polymorphic DNA (RAPD) markers produced by 78 primers, 27 inter-simple sequence repeat (ISSR) markers produced by 17 primers, and a sequence-characterized amplified region (SCAR) marker that was previously reported as linked (1.6 cM) to race-1 Fusarium wilt [incited by Fusarium oxysporum Schlechtend.:Fr. f. sp. niveum (E.F.Sm.) W.C. Synder & H.N. Hans] resistance in watermelon. The map consists of 25 linkage groups. Among them are a large linkage group that contains 22 markers covering a mapping distance of 225.6 cM and six large groups each with 10-20 markers covering a mapping distance of 68.8 to 110.8 cM. There are five additional linkage groups consisting of 3-7 markers per group, each covering a mapping distance of 36.5 to 57.2 cM. The 13 remaining linkage groups are small, each consisting of 2-11 markers covering a mapping distance of 3.5-29.9 cM. The entire map covers a total distance of 1,166.2 cM with an average distance of 8.1 cM between two markers. This map is useful for the further development of markers linked to disease resistance and watermelon fruit qualities.

Isolation and characterization of VGF peptides in rat brain. Role of PC1/3 and PC2 in the maturation of VGF precursor

The neurotrophin responsive gene vgf is widely expressed in central and peripheral neurones, and in certain neuroendocrine cell populations. Its encoded VGF precursor protein (proVGF1: 617 amino acids in rat, 615 in man, > 85% homology) gives rise to several low molecular weight species. We studied a range of neuroendocrine and neuronal cells, in which VGF-processing products were prominent with an apparent molecular weight of 20 and 10 kDa (VGF20 and VGF10, respectively). Such peptides were recognized by antibodies specific for the C-terminal rat VGF nonapeptide, thus indicating that they included the C-terminus of proVGF. Ectopic expression of the neuroendocrine-specific prohormone convertases PC1/3 or PC2 in GH3 cells showed that both could generate VGF20, while VGF10 was preferentially produced by PC1/3. Site-directed mutagenesis was used to identify the KRKRKK(488) motif as the target within VGF sequence which leads to the production of VGF20. Molecular characterization of rat VGF10, on the other hand, revealed that this peptide is produced by cleavage at the RPR(555) site. By the combined use of high-resolution separation techniques, matrix-assisted laser desorption/ionization time of flight (MALDI-ToF) mass spectrometry and manual Edman degradation we identified in rat brain a VGF fragment analogous to bovine peptide V and two novel peptides also derived from the C-terminal region of proVGF.

Identification of neonatal hearing impairment: hearing status at 8 to 12 months corrected age using a visual reinforcement audiometry protocol

OBJECTIVES

1) To describe the hearing status of the at-risk infants in the National Institutes of Health-Identification of Neonatal Hearing Impairment study sample at 8 to 12 mo corrected age (chronologic age adjusted for prematurity). 2) To describe the visual reinforcement audiometry (VRA) protocol that was used to obtain monaural behavioral data for the sample.

DESIGN

All neonatal intensive care unit infants and well babies with risk factors (including well babies who failed neonatal tests) were targeted for follow-up behavioral evaluation once they had reached 8 mo corrected age. Three thousand one hundred and thirty-four (64.4%) of the 4868 surviving infants returned for at least one behavioral hearing evaluation, which employed a well-defined VRA protocol. VRA thresholds or minimum response levels (MRLs) were determined for speech and pure tones of 1.0, 2.0, and 4.0 kHz for each ear using insert earphones.

RESULTS

More than 95% of the infants were reliably tested with the VRA protocol; 90% provided complete tests (four MRLs for both ears). Ninety-four percent of the at-risk infants were found to have normal hearing sensitivity (MRLs of 20 dB HL) at 1.0, 2.0, and 4.0 kHz in both ears. Of the infants, 2.2% had bilateral hearing impairment, and 3.4% had impairment in one ear only. More than 80% of the impaired ears had losses of mild-to-moderate degree.

CONCLUSIONS

This may be the largest study to attempt to follow all at-risk infants with behavioral audiometric testing, regardless of screening outcome, in an effort to validate the results of auditory brain stem response, distortion product otoacoustic emission, and transient evoked otoacoustic emission testing in the newborn period. It is one of only a few studies to report hearing status of infants at 1 yr of age, using VRA on a clinical population. Successful testing of more than 95% of the infants who returned for the VRA follow-up documents the feasibility of obtaining monaural behavioral data in this population.

VGF: a novel role for this neuronal and neuroendocrine polypeptide in the regulation of energy balance

Insight into the mechanisms of action of neurotrophic growth factors has been obtained through the identification and characterization of gene products that are regulated or modified at the transcriptional, translational, and/or posttranslational level in response to neurotrophin treatment. VGF (non-acronymic) was identified approximately 15 years ago as a nerve growth factor (NGF)-regulated transcript in rat PC12 pheochromocytoma cells. Subsequent studies have demonstrated that neurotrophins such as NGF and brain-derived neurotrophic factor induce vgf gene expression relatively rapidly in PC12 cells and cultured cortical neurons, respectively, in comparison to less robust regulation by epidermal growth factor (EGF) and insulin, growth factors which do not trigger the neuronal differentiation of PC12 cells. vgf gene expression is stimulated in vitro by NGF and the ras/map kinase signaling cascade through a CREB-dependent mechanism, while in vivo, VGF mRNA levels are regulated by neuronal activity, including long-term potentiation, seizure, and injury. Both the mRNA and encoded approximately 68-kDa protein (VGF) are selectively synthesized in neuroendocrine and neuronal cells. The predicted VGF sequence is rich in paired basic amino acid residues that are potential sites for proteolytic processing, and VGF undergoes regulated release from dense core secretory vesicles. Although VGF mRNA is synthesized widely, by neurons in the brain, spinal cord, and peripheral nervous system, its expression is particularly abundant in the hypothalamus. In addition, VGF peptides are found in hypophysial, adrenal medullary, gastrointestinal, and pancreatic endocrine cells, suggesting important neuroendocrine functions. Recent analysis of VGF knockout mice indeed demonstrates that VGF plays a critical role in the control of energy homeostasis. VGF knockout mice are thin, small, hypermetabolic, hyperactive, and relatively infertile, with markedly reduced leptin levels and fat stores and altered hypothalamic pro-opiomelanocortin, neuropeptide Y, and agouti-related peptide expression. Coupled with the demonstration that VGF mRNA levels are induced in the normal mouse hypothalamic arcuate nuclei in response to fasting, important central and peripheral roles for VGF in the regulation of metabolism are suggested. Here we review previous studies of VGF in the broader context of its newly recognized role in the control of energy balance and propose several models and experimental approaches that may better define the mechanisms of action of VGF.

Activation of TrkA tyrosine kinase in embryonal carcinoma cells promotes cell compaction, independently of tyrosine phosphorylation of catenins

Cadherins are transmembrane receptors whose extracellular domain mediates homophilic cell-cell interactions, while their cytoplasmic domain associates with a family of proteins known as catenins. Although the mechanisms that regulate the assembly and functional state of cadherin-catenin complexes are poorly understood, current evidence supports a role for protein tyrosine kinase activity in regulating cell adhesion and migration. Tyrosine phosphorylation of catenins is thought to mediate loss of intercellular adhesion promoted by activation of receptor tyrosine kinases in epithelial cells. Here, we show that activation of ectopically expressed TrkA, the tyrosine kinase receptor for nerve growth factor (NGF), stimulates embryonal carcinoma P19 cells to develop extensive intercellular contacts and to assemble into closely packed clusters. Thus, activation of receptor tyrosine kinases can differentially regulate adhesiveness by cell-type-specific mechanisms. Furthermore, activation of TrkA in P19 and epithelial MDCK cells induces tyrosine phosphorylation of p120(ctn) and of beta-catenin, irrespective of the elicited cellular response. The selective Src tyrosine kinase inhibitor PP2, however, suppresses NGF- or HGF-induced tyrosine phosphorylation of catenins in both P19 and MDCK cells without interfering with the acquisition of a compacted or scattered phenotype. These findings provide a cogent argument for considering that tyrosine phosphorylation of catenins is dispensable for their interaction with cadherins and, ultimately, for the modulation of cadherin-based cell adhesion by receptor tyrosine kinases.

Significant beat-to-beat hemodynamic changes in fetal circulation: a consequence of abrupt intrathoracic pressure variation induced by hiccup

During routine fetal echocardiographic studies, we incidentally observed abrupt beat-to-beat changes in blood flow velocity and direction during bouts of hiccups in fetuses with a normal heart and regular and synchronized atrioventricular cardiac rhythm. The effect of hiccups on blood flow velocity and direction varied depending on the time of occurrence of hiccups during the cardiac cycle. In systole, a significant transient reduction of peak flow velocity occurred at the aortic and pulmonic valves, and brief tricuspid regurgitation appeared synchronously with each hiccup. In diastole, a transient reversal of flow direction was recorded simultaneously with the hiccup at the aorta and ductus arteriosus, and acceleration of peak flow velocity was observed across the tricuspid and mitral valves. Throughout the entire cardiac cycle, marked blood flow acceleration was observed in the superior vena cava, inferior vena cava, and ostium secundum simultaneously with the hiccup. A direct transmission of briefly augmented, negative intrathoracic pressure to a compliant aorta and systemic veins appears to be a reasonable explanation for most of our observations.

Headache in schizophrenic patients: a controlled study

Various studies have indicated that chronic schizophrenic patients share a lower rate of headaches than the normal population. A questionnaire concerning the symptomatology of headache was administered to 108 schizophrenic patients in the chronic stage and to 100 normal subjects. The questions dealt with type, location, frequency, severity, and duration of headache, as well as with its accompanying phenomena. Both groups shared a high distribution of headache reports, and generally no significant differences were observed in the various parameters. It was found that schizophrenic patients tend to refrain from complaining about their headache, although they are capable of its precise description. No correlation was found between the type of headache and type of schizophrenia.

Expression, processing, and secretion of the neuroendocrine VGF peptides by INS-1 cells

The neurotropin-inducible gene vgf is expressed in neuronal and endocrine tissues. It encodes a secretory protein that is proteolytically processed in neuronal cells to low molecular mass polypeptides. In the present report, we show that vgf is expressed in different insulinoma cell lines and in normal rat pancreatic islets. In the insulinoma-derived beta-cell line INS-1, vgf messenger RNA was transcriptionally up-regulated by increased levels ofintracellular cAMP, but not by the addition of glucose (20 mM) or phorbol 12-myristate 13-acetate (100 nM). Furthermore, nerve growth factor failed to stimulate vgf gene expression. In INS-1 cells, the VGF protein was shown to be processed in a post endoplasmic reticulum compartment to produce a peptide profile similar to that seen in neurons. The release of such VGF peptides occurred at a low rate in the absence of secretory stimuli (<2%/h). A 3-fold increase in the rate of release was seen after the addition of glucose (15 mM), a 4-fold increase was seen after (Bu)2cAMP (1 mM), and a 6-fold increase was seen after phorbol 12-myristate 13-acetate (100 nM). These results indicated that insulin-containing cells produce VGF-derived peptides that are released via a regulated pathway in response to insulin secretagogues.

Induction of telomerase activity in v-myc-transformed avian cells

Telomerase activity is detectable in the majority of tumors or immortalized cell lines, but is repressed in most normal human somatic cells. It is generally assumed that reactivation of telomerase prevents the erosion of chromosome ends which occurs in cycling cells and, hence, hinders cellular replicative senescence. Here, we show that the expression of v-Myc oncoprotein by retroviral infection of telomerase-negative embryonal quail myoblasts and chicken neuroretina cells is sufficient for reactivating telomerase activity, earlier than telomere shortening could occur. Furthermore, the use of a conditional v-Myc-estrogen receptor protein (v-MycER) causes estrogen-dependent expression of detectable levels of telomerase activity in recently infected chick embryo fibroblasts and neuroretina cells. We conclude that the high levels of telomerase activity in v-Myc-expressing avian cells are not the mere consequence of transformation or of a differentiative block, since v-Src tyrosine kinase, which prevents terminal differentiation and promotes cell transformation, fails to induce telomerase activity.

Increased sensitivity and reproducibility of TRAP assay by avoiding direct primers interaction

Telomeric Repeat Amplification Protocol (TRAP) is a sensitive procedure to measure telomerase activity in small samples of cell or tissue extracts. Due to the strict correlation between high levels of telomerase activity and neoplastic transformation, TRAP assay could provide an important diagnostic marker of malignancy. Although the original TRAP assay is very sensitive and some improvements have been described, occasional artifacts still persist in the modified procedures. Here we describe how changes in the sequence of the primer used for the amplification step enhance the reproducibility and sensitivity in the TRAP assay.

Cloning, structural organization analysis, and chromosomal assignment of the human gene for the neurosecretory protein VGF

The Vgf gene was originally identified as a 2.7-kb cDNA fragment isolated from nerve growth factor-treated PC12 cells by differential display against PC12 cells. It is transcribed solely in subpopulations of neuroendocrine cells in vivo and it is induced by neurotrophins in target cells in vitro. The single-copy human VGF gene was isolated from a genomic library. The gene spans approximately 6 kb and contains two exons. The entire VGF protein is encoded by exon 2, while exon 1 contains only 5'-untranslated sequence. The structural organization of the human gene is similar to that described for the rat Vgf gene (S. R. J. Salton et al., 1991, Mol. Cell. Biol. 11: 2335-2349) and both the translated and the untranslated regions show a high degree of sequence homology to the rat gene. Northern blot analysis revealed a single transcript of approximately 2.7 kb that was detected only in mRNA preparations from brain. The gene was assigned to chromosome 7q22 by fluorescence in situ hybridization.