Complete Sequence of a 93.4-kb Contig from Chromosome 3 of Trypanosoma cruzi Containing a Strand-Switch Region

We have initiated large-scale sequencing of the third smallest chromosome of the CL Brener strain of Trypanosoma cruzi and we report here the complete sequence of a contig consisting of three cosmids. This contig covers 93.4 kb and has been found to contain 20–30 novel genes and several repeat elements, including a novel chromosome 3-specific 400-bp repeat sequence. The intergenic sequences were found to be rich in di- and trinucleotide repeats of varying lengths and also contained several known T. cruzi repeat elements. The sequence contains 29 open reading frames (ORFs) longer than 700 bp, the longest being 5157 bp, and a large number of shorter ORFs. Of the long ORFs, seven show homology to known genes in parasites and other organisms, whereas four ORFs were confirmed by sequencing of cDNA clones. Two shorter ORFs were confirmed by a database homology and a cDNA clone, respectively, and one RNA gene was identified. The identified genes include two copies of the gene for alanine-aminotransferase as well as genes for glucose-6-phosphate isomerase, protein kinases and phosphatases, and an ATP synthase subunit. An interesting feature of the sequence was that the genes appear to be organized in two long clusters containing multiple genes on the same strand. The two clusters are transcribed in opposite directions and they are separated by an ~20-kb long, relatively GC-rich sequence, that contains two large repetitive elements as well as a pseudogene for cruzipain and a gene for U2snRNA. It is likely that this strand switch region contains one or more regulatory and promoter regions. The reported sequence provides the first insight into the genome organization of T. cruzi and shows the potential of this approach for rapid identification of novel genes.     

Genome profiles of bilateral dysgerminomas, a unilateral gonadoblastoma, and a metastasis from a 46, XY phenotypic female

We present a case report of a 16-year-old, phenotypic female with bilateral dysgerminomas, a unilateral gonadoblastoma, and a peritoneal metastasis. The patient's constitutional karyotype was 46,XY. The chromosomal copy number, examined by the comparative genomic hybridization technique, showed 3 gains in the dysgerminoma of the right ovary, 6 gains in the dysgerminoma of the left ovary, and 2 gains and 1 loss in the gonadoblastoma of the left ovary. The metastasis showed 5 gains of which 4 were also observed in the dysgerminoma of the left ovary. The DNA ploidy classifications of the gonadoblastoma and the dysgerminoma in the right ovary were tetraploid, whereas the dysgerminoma in the left ovary and the metastasis were aneuploid. We therefore propose that the metastasis most probably developed from the dysgerminoma of the left ovary.     

The effect of a high calory diet on hormonal changes in young men during prolonged physical strain and sleep deprivation

Summary Major changes occur in the serum level of several hormones during 5 days of heavy and continuous physical activities, with less than a total of 2 h of sleep. The present investigation was designed to evaluate the importance of caloric deficiency, energy requirement being about 8,000–10,000 kcal/24 h. A comparison between well fed subjects and those with food deprivation revealed significantly higher levels of (T₃) triiodothyronin, insulin and thyroid stimulating hormone (TSH) in the well-fed subjects, who also had lower levels of growth hormone (hGH) and cortisol, whereas no difference was found between the two groups for thyroxin (T₄). Increased levels were found for T₃ and T₄ in both groups during the first day of activity, with a concomitant decrease in TSH and a subsequent decrease of T₄ during the next 2 days. T₃ decreased only in the low-calory group whereas increased levels were found in the iso-calory group throughout the course. The resting levels of insulin decreased during the course in the low-calory group whereas it increased in the iso-calory group. High levels were maintained throughout the course for hGH. Cortisol showed high levels just before the start of the course and then decreased from day 2 to day 4. No difference was found between the morning and evening levels for cortisol, indicating disappearance of the circadian rhythm. The present investigation has shown that energy deficiency during prolonged physical strain is responsible for the decreased serum levels of T₃ and insulin and may contribute to the decrease in TSH and the increase in hGH and cortisol.     

Chemoattractant-induced NADPH oxidase activity in human monocytes is terminated without any association of receptor-ligand complex to cytoskeleton

When the chemotactic peptide formylmethionyl-leucyl-phenylalanine binds to its cell surface receptor, a transmembrane signal is generated that activates the superoxide-producing NADPH oxidase of human phagocytes. Comparing monocytes and neutrophils with regard to the production of superoxide anion induced by the peptide, we found a similar time-course for both types of cells. In neutrophils, ligand binding induced a conversion of the receptor to a high-affinity form, a change suggested to be due to an association of the receptor-ligand complex to the Triton X-100-insoluble cytoskeleton. This event has been hypothesized to terminate the signal that activates the NADPH oxidase and thereby results in cessation of the cellular production of superoxide anion. Neutrophils preincubated with the cytoskeleton-disrupting drug cytochalasin B showed an increased and prolonged superoxide anion production after activation with the peptide, thus indicating that the cytoskeleton is involved in terminating this response. Formylmethionyl-leucyl-phenylalanine was also found to induce polymerization of actin in monocytes; however, cytochalasin B had no effect on the peptide-induced generation of superoxide anion in these cells. Furthermore, also in monocytes, ligand binding induced a conversion of the receptor to a high-affinity form; however, the receptor-ligand complex did not coisolate with the Triton X-100-insoluble cytoskeleton. These results indicate that, in monocytes, the NADPH oxidase activating pathway is terminated without any association of the receptor-ligand complex to the Triton X-100-insoluble cytoskeleton.     

Expression of CD44 in effusions of patients diagnosed with serous ovarian carcinoma – diagnostic and prognostic implications

CD44 is a family of cell adhesion molecules involved in a variety of cellular functions. The present study analysed the expression of two CD44 isoforms in serous effusions of patients diagnosed with ovarian carcinoma and corresponding primary and metastatic lesions. Fifty-eight effusions, 23 primary ovarian tumours, and 44 metastatic lesions were studied for protein expression of CD44s and v3-10 using immunohistochemistry. Results were correlated with clinical parameters. CD44v3-10 was seen in carcinoma cells in the majority of cases at all sites. Malignant effusions showed an up-regulation of CD44s compared to both primary tumours and metastatic solid lesions. Mesothelial cells frequently expressed CD44s, but were rarely immunoreactive for v3-10. CD44s immunoreactivity in cancer cells in effusions was significantly more often observed in patients with FIGO stage 3 than in stage 4 patients (P = 0.045). Staining results did not correlate with age, effusion site, metastatic site, tumour grade or residual tumour mass after initial surgery. Likewise, comparison of overall and disease-free survival with expression of the CD44 isoforms studied did not reveal any statistically significant associations. The up-regulation in CD44 levels in effusions, primarily in stage 3 disease, suggests that adhesion of ovarian carcinoma cells to mesothelium may be regulated at the level of CD44s expression, and provides further evidence of phenotypic alteration in the transition from primary tumour cell clones to effusions. The similar expression profile of CD44 in carcinoma cells in peritoneal and pleural effusions supports our previous observations and the hypothesis that carcinoma cells in peritoneal effusions are truly metastatic. This revised version was published online in July 2006 with corrections to the Cover Date.     

'Vanishing embryo syndrome' in IVF/ICSI

BACKGROUND: In a Danish population-based cohort study assessing the risk of cerebral palsy in children born after IVF, we made some interesting observations regarding 'vanishing co-embryos'. METHODS and RESULTS: All live-born children born in Denmark from 1 January 1995 to 31 December 2000 were included in this analysis. The children conceived by IVF/ICSI (9444) were identified through the IVF Register, the children conceived without IVF/ICSI (395 025) were identified through The Danish Medical Birth Register. Main outcome measure was the incidence of cerebral palsy. Within the IVF/ICSI children we found indications of an increased risk of cerebral palsy in those children resulting from pregnancies, where the number of embryos transferred was higher than the number of children born. CONCLUSIONS: The association between vanishing embryo syndrome and incidence of cerebral palsy following IVF requires further investigation in larger, adequately powered, studies.     

Eccentric and concentric torque-velocity characteristics of the quadriceps femoris in man

Summary The primary purpose of this investigation was to study the eccentric and concentric torque-velocity characteristics of the quadriceps femoris in man using a recently developed combined isometric, concentric and eccentric controlled velocity dynamometer (the SPARK System). A secondary purpose was to compare the method error associated with maximal voluntary concentric and eccentric torque output over a range of testing velocities. 21 males (21–32 years) performed on two separate days maximal voluntary isometric, concentric and eccentric contractions of the quadriceps femoris at 4 isokinetic lever arm velocities of 0° · s^–1 (isometric), 30° · s^–1 120° · s^–1 and 270° · s^–1. Eccentric peak torque and angle-specific torques (measured every 10° from 30° to 70°) did not significantly change from 0° · s^–1 to 270° · s^–1 (p>0.05) (with the exception of angle-specific 40° torque, which significantly increased;p<0.05). The mean method error was significantly higher for the eccentric tests (10.6%±1.6%) than for the concentric tests (8.1%±1.7%) (p<0.05). The mean method error decreased slightly with increasing concentric velocity (p>0.05), and increased slightly with increasing eccentric velocity (p>0.05). A tension restricting neural mechanism, if active during maximal eccentric contractions, could possibly account for the large difference seen between the present eccentric torque-velocity results and the classic results obtained from isolated animal muscle.     

The regulatory role of FSH in steroid formation by luteinized human granulosa cells in culture

Granulosa cells were aspirated from human pre-ovulatory folliclesfollowing a combined clomiphene-gonadotrophin stimulation inan in-vitro fertilization (IVF) programme. The cells were culturedfor 8 days in medium M199 containing 10% bovine fetal calf serumunder 5% CO₂ in air. Pure human FSH and human LH were addedalone or in combination to the culture in various concentrationsand the progesterone (P) and oestradiol-17rnals.org/math/beta.gif" ALT="{beta}" BORDER="0"> (E₂) levels in themedium were measured every second day by a conventional RIAtechnique. In the presence of FSH or LH the formation of P increased2- to 3-fold with the pronounced effect after 4 to 6 days inculture. Addition of testosterone (T) (3 ? 10^–7 M) tothe culture medium affected neither basal nor gonadotrophinstimulated P formation. In this system, only minute amountsof E₂ were formed and neither FSH nor LH stimulated its formation.When the medium was fortified with T, basal E₂ formation increased50- to 100-fold. FSH further stimulated this conversion significantlyafter 6 and 8 days of culture, while LH had no significant influence.     

Manipulations in Maternal Environment Reverse Periodontitis in Genetically Predisposed Rats

The predisposition to develop periodontitis is partly genetically determined in humans as well as in animals. Here we demonstrate, however, that early manipulations in the maternal environment of an animal (rat) model of periodontitis can fully reverse the genetic predisposition to develop periodontitis at adult age.     

Receiver operating characteristic study of image preprocessing for teleradiology and digital workstations

The purpose of this study was to evaluate whether digitized analog images displayed on a digital workstation can be improved by using a preprocessing algorithm, and if so, whether the quality of the resulting images can reach that of the original films. The material contained 120 difficult cases (about 50% with selected pathology). Four radiologists each evaluated half of the randomly ordered cases with the digital workstation and half of the cases with the original radiographs. The data were compared with a previous similar study, where the workstation had no option for preprocessed images. Preprocessed digital images were clearly superior to digital images without preprocessing, although for those of the highest diagnostic difficulty they were inferior to the original films. The preprocessing algorithm has improved the diagnostic quality of the digital workstation. There is room yet for improvement compared to plain films, although the current setup may be sufficient in some settings.