bluuebunny/crossref_metadata_2025 huggingface dataset:
The B chromosome polymorphism of the grasshopper Eyprepocnemis plorans in North Africa. IV. Transmission of rare B chromosome variants
Authors: Bakkali M. , Camacho J.P.M.
Published: August 2004

In addition to the principal B chromosome (B1) in Moroccan populations of the grasshopper Eyprepocnemis plorans, nine B chromosome variants appeared at low frequency. The transmission of five of these rare B chromosome variants through females was analysed in three natural populations. Sixteen controlled crosses provided useful information on the transmission of BM2, BM6 and BM7 in Smir, BM3 and BM6 in SO.DE.A. (Société de Développement Agricole lands near Ksar-el-Kebir city), and BM2 and BM10 in Mechra, all located in Morocco. Since six female parents carried two different B variants, a total of 22 progeny analyses could be studied. Intraindividual variation in B transmission rate (kB) was observed among the successive egg pods in 26.7 % of the females, but this variation did not show a consistent temporal pattern. Only the BM2 and BM6 variants in Smir showed net drive, although variation was high among crosses, especially for BM2. These two variants are thus good candidates for future regenerations (the replacement of a neutralized B, B1 in this case, by a new driving variant, BM2 or BM6) in Smir, the northern population where the B polymorphism is presumably older. The analysis of all crosses performed in the three populations, including those reported previously for the analysis of B1 transmission, showed that the largest variance in kB among crosses stands at the individual level, and not at population or type of B levels. The implications of these findings for the occurrence of possible regeneration processes in Moroccan populations are discussed.
B chromosomes and Robertsonian fusions of Dichroplus pratensis (Acrididae): intraspecific support for the centromeric drive theory
Authors: Bidau C.J. , Martí D.A.
Published: August 2004

We tested the centromeric drive theory of karyotypic evolution in the grasshopper Dichroplus pratensis, which is simultaneously polymorphic for eight Robertsonian fusions and two classes of B chromosomes. A logistic regression analysis performed on 53 natural populations from Argentina revealed that B chromosomes are more probably found in populations with a higher proportion of acrocentric chromosomes, as the theory predicts. Furthermore, frequencies of B-carrying individuals are significantly negatively correlated with the mean frequency of different Robertsonian fusions per individual. No significant correlations between presence/absence or frequency of Bs, and latitude or altitude of the sampled populations, were found. We thus provide the first intraspecific evidence supporting the centromeric drive theory in relation to the establishment of B chromosomes in natural populations.
Spatio-temporal dynamics of a neutralized B chromosome in the grasshopper Eyprepocnemis plorans
Authors: Perfectti F. , Pita M. , de la Vega C.G. , Gosálvez J. , Camacho J.P.M.
Published: August 2004

Spatial and temporal patterns of frequency variation for a neutralized B chromosome in the grasshopper Eyprepocnemis plorans were analyzed along six transects in the east of Spain to explore possible factors affecting the population dynamics of this polymorphism. Three parameters were employed to quantify B frequency: prevalence, load and mean frequency. Of them, load seemed to be the less sensitive parameter, probably due to its small range of variation. Prevalence, however, shows ample variation, but the mean frequency of B chromosomes per individual is the best parameter to characterize B frequency. Only river transects revealed significant differences among populations, and the use of two geographic explicit approaches (Mantel test and distograms) revealed significant isolation by distance (IBD), especially at the Segura River mouth, presumably due to low gene flow and drift. No temporal trend was found in the Segura River transects, which is consistent with the slow changes in B frequency expected during the random walk for neutralized B chromosomes. But these transects showed a clear spatial pattern, with B1 showing lower frequency in the upper course of this river. The present results provide the first empirical evidence of IBD in the evolution of a neutralized B chromosome, and support the notion that B dynamics at this evolutionary stage is best explained by a metapopulation approach.
The parasitic effects of rye B chromosomes might be beneficial in the long term
Authors: González-Sánchez M. , Chiavarino M. , Jiménez G. , Manzanero S. , Rosato M. , Puertas M.J.
Published: August 2004

Rye B chromosomes (Bs) have strong parasitic effects on fertility. B carrying plants are less fertile than 0B ones, whereas the Bs have no significant effects on plant vigour. On the other hand, it has been reported that B transmission is under genetic control in such a way that H line plants transmit the Bs at high frequency, whereas the Bs in the low B transmission rate line (L) fail to pair at metaphase I and are frequently lost. In the present work we analyse variables affecting vigour and fertility considering not only the number of Bs of each plant, but also its H or L status and the B number of its maternal parent. Our results show that the Bs not only decrease female fertility of the B carrier, but the fertility of its progeny, with the exception of 0B plants coming from a 4B mother, which are the most fertile. In this way B chromosomes can be considered as a selective factor. Pollen abortion was higher in B carriers, in the progeny of B carriers and in H plants, but 4B plants coming from B carrying mothers produce less aborted pollen, indicating that a high B number is more deleterious if it is transmitted in the pollen grains. A similar result was obtained for endosperm quality estimated as grain weight, because it is negatively influenced by the Bs in 4B plants coming from a 0B mother. H plants were always less fertile than L ones, indicating that alleles increasing the loss of Bs in the L line will be probably selected as a defence of the A genome against the invasive Bs of the H line. Flower number is not affected by the Bs.
Interaction of B chromosomes with A or B chromosomes in segregation in insects
Authors: Nokkala S. , Nokkala C.
Published: August 2004

Additional or B chromosomes not belonging to the regular karyotype of a species are found in many animal and plant groups. They form a highly heterogeneous group with respect to their morphology and behaviour both in mitosis and meiosis. Achiasmatic mechanisms that ensure the segregation of a B chromosome from another B chromosome or from an A chromosome are reviewed. An achiasmatic mechanism characterized by the “distance pairing” of segregating univalents at metaphase I was found to be responsible for the preferential segregation of B chromosome univalents in Hemerobius marginatus L. (Neuroptera), and a mechanism characterized by the “touch and go pairing” of segregating univalents was responsible for the highly regular segregation of a B chromosome and the X chromosome in Rhinocola aceris (L.) (Psylloidea, Homoptera). The latter mechanism resulted in the integration of a B chromosome to the A chromosome set as a Y chromosome in a psyllid species Cacopsylla peregrina (Frst.). Furthermore, B chromosomes can disturb the regular segregation of the achiasmatic X and Y chromosomes resulting in the formation of X0/XY polymorphism in a population, which might precede the loss of the Y chromosome. The absence of observations on accurately functioning achiasmatic segregation mechanisms in grasshoppers (Orthoptera) was attributed to the X and B chromosomes, which re-orient one or several times during metaphase I. Apparently, these re-orientations mask any achiasmatic segregation mechanism that might operate during meiotic prophase in these insects.
Effects of Mild Vitamin A Deficiency on Lung Maturation in Newborn Rats: A Morphometric and Morphologic Study
Authors: Frey Gaby , Egli Evelyne , Chailley-Heu Bernadette , Lelièvre-Pégorier Martine , Burri Peter H. , Bourbon Jacques , Tschanz Stefan A.
Published: August 2004

Objective: To evaluate the effects of a 60% vitamin A deficiency (VAD) on the two postnatal stages of lung development: alveolarization and microvascular maturation. Lungs from deficient rats were compared to age-matched controls. Study Design: Starting at 3 weeks before mating, female rats were maintained under a diet lacking vitamin A. Due to the slow depletion of the vitamin A liver stores the pregnant rats carried to term and delivered pups under mild VAD conditions. Mothers and offspring were then kept under the same diet what resulted in a mean reduction of vitamin A plasma concentration of about 60% vs. controls during the whole experimental period. Pups were sacrificed on days 4, 10 and 21 and their lungs fixed and analyzed by means of a combined morphologic and morphometric investigation at light and electron microscopic levels. Results: During the whole experiment, body weights of VAD animals were lower than controls with a significant decrease on day 10. On days 4, 10 and 21 the pulmonary structure was in a comparable gross morphologic state in both groups. Despite this morphologic normality, quantitative alterations in some functional parameters could be detected. On day 4, lung volume and the volume and surface area of air spaces were decreased, while the arithmetic mean barrier thickness and type 2 pneumocyte volume were increased in the VAD group. On day 21, some changes were again manifest mainly consisting in an augmentation of the vascularization and a decrease in interstitial volume in deficient animals. Conclusions: Mild VAD causes no gross disturbances in the postnatal phases of lung development in rats. However, a body weight-related transient retardation of lung maturation was detectable in the first postnatal week. At 3 weeks, the VAD lungs showed a more mature vascular system substantiated by an increase in volume of both capillary volume and the large non-parenchymal vessels. In view of these quantitative alterations, we suspect that mild VAD deregulates the normal phases of body and lung growth, but does not induce serious functional impairments.
Predictive Factors for Noncompliance with Follow-Up among Women Treated for Cervical Intraepithelial Neoplasia
Authors: Bornstein Jacob , Bahat-Sterensus Hila
Published: August 2004

The aim of this study was to explore the magnitude and causes of noncompliance with follow-up after cervical intraepithelial neoplasia (CIN) treatment. Women who were treated by large loop excision of the transformation zone (LLETZ) for CIN between January 1994 and June 1996 were enrolled. Women who kept all their appointments were grouped as compliant. To the noncompliant group belonged those women who missed at least two follow-up appointments during the first year of follow-up. Seventy-four of 141 women (52.5%) who were treated for CIN were noncompliant. Fifty women from each group were then evaluated. Demographic, social and contraceptive parameters were found to be similar between the groups. The noncompliant group had a nonsignificant trend towards having had only elementary education, undergoing surgery in the past, additional diseases, taking chronic medications and having diseases in the family. We conclude that noncompliance with follow-up after treatment of CIN by LLETZ may be much higher than expected. Noncompliant patients do not have any significantly defined characteristics.
Adsorptive Granulocyte and Monocyte Apheresis versus Prednisolone in Patients with Corticosteroid-Dependent Moderately Severe Ulcerative Colitis
Authors: Hanai Hiroyuki , Watanabe Fumitoshi , Yamada Masami , Sato Yoshihiko , Takeuchi Ken , Iida Takayuki , Tozawa Kotaro , Tanaka Tatsuo , Maruyama Yasushi , Matsushita Isao , Iwaoka Yasushi , Kikuch Kazuto , Saniabadi Abby R.
Published: August 2004

Background/Aim: Active ulcerative colitis (UC) is often associated with increased peripheral granulocytes and monocytes/macrophages which show activation behavior and prolonged survival time. Further, mucosal granulocyte level parallels intestinal inflammation and can predict UC relapse. Accordingly, our aim was to see if adsorptive granulocyte/monocyte apheresis (GMA) can promote remission and spare steroid in patients with steroid-dependent (SD) UC. Methods: 69 SD patients, at the time of relapse, were randomly assigned to groups I (n = 46) and II (n = 23). The mean dose of prednisolone (PSL) was 12 mg/day/patient, CAI (clinical activity index) 9.2 in both groups. Group I patients were given up to 11 GMA sessions over 10 weeks with Adacolumn; in group II, the mean dose of PSL was increased to 30 mg/day/patient. Results: At week 12, 83% of group I and 65% of group II patients were in remission, CAI in group I was 1.7 (p < 0.001) and in group II, 2.5 (p < 0.001). Further, during the 12 weeks of treatment, the cumulative amount of PSL received per patient was 1,157 mg in group I and 1,938 mg in group II (p = 0.001). Conclusions: GMA appeared to be an effective adjunct to standard drug therapy of moderately severe UC by promoting remission and sparing steroids.
Gallbladder Involvement of Henoch-Schönlein Purpura Mimicking Acute Acalculous Cholecystitis
Authors: Hoffmann Jörg C. , Cremer Philipp , Preiss Jan C. , Ebhardt Harald , Kruschewski Martin , Buhr Heinz-Johannes , Zeitz Martin
Published: August 2004

Background/Aims: We report the case of a 53-year-old man with fever and severe abdominal pain following an upper respiratory tract infection. Methods/Results: The clinical signs, the laboratory markers, and the ultrasound findings were consistent with acute acalculous cholecystitis and he underwent cholecystectomy. Histologically the gallbladder showed vasculitis and the patient developed postoperatively a purpuric rash of the legs with transient ankle arthritis. Gastroscopy revealed prepyloric ulcers consistent with vasculitis. The patient was diagnosed as having Henoch-Schönlein purpura. Gastric ulcers as well as arthritis disappeared upon treatment with corticosteroids and proton pump inhibitors. Conclusion: Taken together, Henoch-Schönlein purpura can mimic acute cholecystitis and should be considered as a rare differential diagnosis of acute cholecystitis.
Gastric Emptying of a Solid Meal Starts during Meal Ingestion: Combined Study Using 13C-Octanoic Acid Breath Test and Doppler Ultrasonography
Authors: Minderhoud Itta M. , Mundt Marco W. , Roelofs Jan M.M. , Samsom Melvin
Published: August 2004

Scintigraphy and the 13C-octanoic acid breath test are both applied to assess gastric emptying. Using the 13C-octanoic acid breath test, excretion curves show 13C excretion immediately after ingestion of a solid egg meal, in contrast with scintigraphy where gastric emptying is observed after a lag phase. The aim of our study was to investigate whether transpyloric flow occurs during and directly after meal ingestion. Therefore, transpyloric flow was measured during and after ingestion of an egg meal labeled with 13C-octanoic acid, using Doppler ultrasonography. The breath test was performed simultaneously, with samples taken at regular intervals. The first emptying episode was observed 6.9 (3.9–16.2) min after start of meal ingestion. A significant relation between recovery of 13C and total duration of gastric emptying during the first 20 min was observed (partial correlation coefficient r = 0.80, p < 0.001). In conclusion, transpyloric flow starts during ingestion of a solid egg meal and results in detectable excretion of 13C.
Prevalence of Inherited Ataxias in the Province of Padua, Italy
Authors: Zortea M. , Armani M. , Pastorello E. , Nunez G.F. , Lombardi S. , Tonello S. , Rigoni M.T. , Zuliani L. , Mostacciuolo M.L. , Gellera C. , Di Donato S. , Trevisan C.P.
Published: August 2004

Few population studies are available on epidemiological indexes of hereditary ataxias. An investigation on the prevalence rate of these movement disorders is in progress for the Veneto region, the main area of northeast Italy with a population of 4,490,586 inhabitants. The first results of this epidemiological survey concern the province of Padua, which numbers 845,203 residents (January 1, 2002). The prevalence rate of inherited ataxias has been estimated at 93.3 cases per million inhabitants. The most common types appeared to be the autosomal dominant forms, namely spinocerebellar ataxia type 1 and 2, with a prevalence of 24 per 1,000,000. In the same population, with a prevalence rate of 6 per 1,000,000, Friedreich’s ataxia was defined as the prominent recessive autosomal form. There were very rare cases of ataxia telangiectasia, ataxia with vitamin E deficiency and cerebellar ataxia with congenital muscular dystrophy, a recently identified autosomal recessive disease.
Effect of Administration of Recombinant Human Leptin during the Neonatal Period on the Plasma Concentration and Gene Expression of Leptin in the Piglet
Authors: Litten J.C. , Mostyn A. , Perkins K.S. , Corson A.M. , Symonds M.E. , Clarke L.
Published: August 2004

Leptin is produced predominantly by white adipocytes and in adults it regulates both appetite and energy expenditure but its role in the neonate remains to be fully established. The aim of this, the first study of leptin administration to Meishan piglets, was to examine the effects of chronic leptin administration to neonatal pigs on their endocrine profile, growth and development. Six Meishan sows gave birth normally at term and 6 pairs of siblings (n = 12), matched by birth weight and gender (male, n = 6; female, n = 6) were randomly allocated to leptin (L: n = 6) or placebo (P: n = 6) administration groups. Piglets remained with their mother throughout the study and from day 3 to 8 of neonatal life each pig received either 4 µg ml–1 kg–1 body weight recombinant human leptin or a saline placebo. Plasma concentrations of key hormones and metabolites were determined in conjunction with messenger RNA (mRNA) for leptin, which was assessed by PCR. Recombinant leptin treatment improved growth performance and promoted skeletal growth in favour of adipose tissue accretion. Circulating plasma leptin concentrations were higher on days 4 and 7 in L pigs. Leptin administration altered the endocrine profile of the neonatal pig, although these changes were not maintained. There were no relationships between plasma leptin and body weight or mRNA leptin abundance, irrespective of treatment. Chronic leptin administration appeared to have a beneficial influence on growth rate and body conformation, which may in part be attributed to alterations in metabolism and nutrient partitioning.
Frontotemporal Dementia: Behavioral Symptoms and Caregiver Distress
Authors: Mourik J.C. , Rosso S.M. , Niermeijer M.F. , Duivenvoorden H.J. , van Swieten J.C. , Tibben A.
Published: August 2004

Objective: To discern behavioral problems that co-occur in frontotemporal dementia (FTD) patients, and to investigate the relation between behavioral clusters and the burden for caregivers. Patients and Methods: Baseline data of 63 FTD patients and their respective caregivers were used to detect the behavioral clusters in the Neuropsychiatric Inventory (NPI) and the accompanying distress evoked in caregivers. To detect the clusters in behavior of the FTD patients, we performed multidimensional scaling (procedure: PROXSCAL). Multiple regression analysis was used to determine the association between behavior of patients and the distress experienced by caregivers. Results: This was the first study that found behavioral clusters for FTD. Two behavioral clusters were found: agitation/psychosis (comprising delusions, hallucinations, irritability and agitation) and mood (made up of anxiety and depression). The remaining NPI domains (euphoria, disinhibition, aberrant motor behavior and apathy were found to be autonomous. After controlling for relevant confounding factors, caregiver distress was strongest related to agitation/psychosis, followed by mood. Disinhibition and aberrant motor behavior were mildly related to caregiver distress. Euphoria and apathy were not significantly related to distress. Caregivers of patients living at home were more distressed by the behavioral problems of the FTD patients than caregivers of hospitalized patients. Discussion: The high prevalence of psychopathology in FTD patients and the associated caregiver distress was confirmed in this study. Clustering behavioral symptoms allows investigation of the relationship between structural or functional cerebral deficits and neuropsychiatric symptoms.
Conversion to Dementia among Two Groups with Cognitive Impairment
Authors: Luis Cheryl A. , Barker Warren W. , Loewenstein David A. , Crum Thomas A. , Rogaeva Ekaterina , Kawarai Toshitaka , St. George-Hyslop Peter , Duara Ranjan
Published: August 2004

Objective: To determine the conversion rates to dementia in patients diagnosed with mild cognitive impairment (MCI) thought to be caused by incipient Alzheimer’s disease (MCI-AD) or with MCI with features of vascular disease (MCI-Vas). Methods: On the basis of patient history, neurocognitive, neurological and MRI evaluation, 99 patients were diagnosed with MCI-AD and 35 with MCI-Vas. Conversion to dementia over an average of a 2.4 ± 1.8-year period was determined. Results: Over the follow-up period, 44% converted to dementia, 51.5% remained classified as MCI, and 4.5% were reclassified as cognitively normal. The conversion rate to dementia was significantly faster at 3 years for the MCI-AD (50.5%) than for the MCI-Vas group (25.7%). The neuropsychological test found to best differentiate converters from non-converters was the Fuld-OME, a measure of learning and recall. Age, education, gender or APOE Ε4 allele frequency did not differentiate converters from non-converters. Conclusions: MCI-AD and MCI-Vas are clinically meaningful subtypes of MCI that may convert to dementia at different rates. Prospective studies on larger subsets of MCI patients are required to confirm these findings.
Molecular Imaging of the Kinetics of Vascular Endothelial Growth Factor Gene Expression in Ischemic Myocardium
Authors: Wu Joseph C. , Chen Ian Y. , Wang Yanling , Tseng Jeffrey R. , Chhabra Ankush , Salek Mahdi , Min Jung-Joon , Fishbein Michael C. , Crystal Ronald , Gambhir Sanjiv S.
Published: August 2004

Background—

Angiogenic gene therapy is a promising treatment paradigm for patients with ischemic heart disease. In this study, we used micro-positron emission tomography (microPET) to monitor the transgene expression, function, and effects in a whole-body system.

Methods and Results—

Adenovirus with cytomegalovirus promoter driving an angiogenic gene (vascular endothelial growth factor [VEGF]) linked to a PET reporter gene (herpes simplex virus type 1 mutant thymidine kinase; Ad-CMV-VEGF
121
-CMV-HSV1-sr39tk) was used to transfect rat embryonic cardiomyoblasts in vitro. Expression of both genes correlated strongly (
r
=0.98;
P
<0.001). Afterward, rats underwent ligation of the left anterior descending artery followed by injection of 1×10
10
pfu of Ad-CMV-VEGF
121
-CMV-HSV1-sr39tk (study; n=35) or Ad-null (control; n=15) at the peri-infarct region. Noninvasive microPET imaging was used to assess the uptake of 9-(4-[
18
F]-fluoro-hydroxymethylbutyl)guanine ([
18
F]-FHBG) PET reporter probe by cells expressing the HSV1-sr39tk PET reporter gene. Cardiac transgene expression peaked at day 1 and declined over the next 2 weeks. Repeat adenoviral injections at day 60 yielded no detectable signal. The in vivo reporter gene expression (% injected dose/g of [
18
F]-FHBG) correlated well with ex vivo gamma counting (
r
=0.92), myocardial tissue HSV1-sr39TK enzyme activity (
r
=0.95), and myocardial tissue VEGF level (
r
=0.94;
P
<0.001 for all). The VEGF
121
isoform induced significant increases in capillaries and small blood vessels. However, the level of neovasculature did not translate into significant improvements in functional parameters such as myocardial contractility by echocardiography, perfusion by nitrogen-13 ammonia imaging, and metabolism by [
18
F]-fluorodeoxyglucose imaging.

Conclusions—

Taken together, these findings establish the feasibility of molecular imaging for monitoring angiogenic gene expression with a PET reporter gene and probe noninvasively, quantitatively, and repetitively. The principles demonstrated here can be used to evaluate other therapeutic genes of interest in animal models before future clinical trials are initiated.
Synergistic effect of SU11248 with cytarabine or daunorubicin on FLT3 ITD–positive leukemic cells
Authors: Yee Kevin W. H. , Schittenhelm Marcus , O'Farrell Anne-Marie , Town Ajia R. , McGreevey Laura , Bainbridge Troy , Cherrington Julie M. , Heinrich Michael C.
Published: August 2004

Fetal liver tyrosine kinase 3 internal tandem duplication (FLT3 ITD) mutations are the most common molecular abnormality associated with adult acute myeloid leukemia (AML). To exploit this molecular target, a number of potent and specific FLT3 kinase inhibitors have been developed and are currently being tested in early phase clinical trials of patients with refractory AML. To explore the efficacy of combining a FLT3 inhibitor with standard AML chemotherapy drugs, we tested the effect of combining the FLT3 inhibitor SU11248 with cytarabine or daunorubicin on the proliferation and survival of cell lines expressing either mutant (FLT3 ITD or FLT3 D835V) or wild-type (WT) FLT3. SU11248 had additive-to-synergistic inhibitory effects on FLT3-dependent leukemic cell proliferation when combined with cytarabine or daunorubicin. The synergistic interaction of SU11248 and the traditional antileukemic agents was more pronounced for induction of apoptosis. SU11248 inhibited the proliferation of primary AML myeloblasts expressing mutant FLT3 ITD but not WT FLT3 protein. Combining SU11248 and cytarabine synergistically inhibited the proliferation of primary AML myeloblasts expressing FLT3 ITD but not WT FLT3 protein. These data suggest that the addition of potent FLT3 inhibitors such as SU11248 to AML chemotherapy regimens could result in improved treatment results.
A down-regulatable E-selectin ligand is functionally important for PSGL-1–independent leukocyte–endothelial cell interactions
Authors: Zanardo Renata C. O. , Bonder Claudine S. , Hwang John M. , Andonegui Graciela , Liu Lixin , Vestweber Dietmar , Zbytnuik Lori , Kubes Paul
Published: August 2004

P-selectin glycoprotein-1 (PSGL-1) supports P-selectin–dependent rolling in vivo and in vitro. However, controversy exists regarding the importance of PSGL-1–dependent and –independent E-selectin rolling. Using antibodies against PSGL-1 and PSGL-1-/- mice, we demonstrated abolition of P-selectin–dependent rolling but only partial inhibition of E-selectin–mediated rolling in the cremaster microcirculation following local administration of tumor necrosis factor α (TNF-α). In vitro studies demonstrated that binding of recombinant mouse E-selectin chimera to PSGL-1-/- neutrophils was dramatically decreased in mice treated systemically but not locally with TNF-α. Further, PSGL-1 blockade abolished E-selectin–dependent rolling in wild-type mice following systemic TNF-α administration but not local TNF-α administration. Together, these data support an E-selectin ligand present on PSGL-1-/- neutrophils that is down-regulatable upon systemic but not local activation. To determine whether the PSGL-1–independent E-selectin ligand was physiologically important, we used a P- and E-selectin–dependent cutaneous contact hypersensitivity model. Binding studies showed no E-selectin ligand down-regulation in this model. The few cells that rolled on E-selectin ligand following PSGL-1 antibody administration or in PSGL-1 deficiency were sufficient to induce profound contact hypersensitivity. In conclusion, E-selectin mediates PSGL-1–dependent and independent rolling and the latter can be down-regulated by systemic activation and can replace PSGL-1 to support the development of inflammation.
Are interleukin-16 and thrombopoietin new tools for the in vitro generation of dendritic cells?
Authors: Bella Silvia Della , Nicola Stefania , Timofeeva Inna , Villa Maria Luisa , Santoro Armando , Berardi Anna C.
Published: August 2004

The effects of interleukin 16 (IL-16) on dendritic cell (DC) generation from human CD34+ progenitor cells are not known. Here, we show that IL-16 added to a basal cocktail comprised of granulocyte-macrophage colony-stimulating factor (GM-CSF), IL-4, Flt-3 ligand (Flt3L), and tumor necrosis factor α (TNF-α) does induce the CD34+ hematopoietic cells to proliferate in vitro and to differentiate into phenotypically and functionally mature DCs. IL-16 exerts this function more efficiently than stem cell factor (SCF) as a control, thrombopoietin (TPO), or IL-16 plus TPO. Moreover, we show that the combination of IL-16 plus TPO induces the generation of tolerogenic DCs, able to induce an anergic state in T cells that persists when T cells are rechallenged with immunogenic DCs. An altered pattern of cytokine production, a reduced expression of the C-type lectin DC-SIGN, and an increased surface expression of the inhibitory molecules immunoglobulin-like transcript 2 (ILT-2), ILT-3, and ILT-4 may all contribute to confer the tolerogenic properties of these DCs. Generation of tolerogenic DCs may aid the exploration of new therapeutic strategies to promote tolerance to autoantigens and prevent disease development. (Blood. 2004;104:4020-4028)
Ultralarge complexes of PF4 and heparin are central to the pathogenesis of heparin-induced thrombocytopenia
Authors: Rauova Lubica , Poncz Mortimer , McKenzie Steven E. , Reilly Michael P. , Arepally Gowthami , Weisel John W. , Nagaswami Chandrasekaran , Cines Douglas B. , Sachais Bruce S.
Published: August 2004

Heparin-induced thrombocytopenia and thrombosis (HITT) is a severe complication of heparin therapy caused by antibodies to complexes between unfractionated heparin (UFH) and platelet factor 4 (PF4) that form over a narrow molar range of reactants and initiate antibody-induced platelet activation. We observed that UFH and tetrameric PF4 formed ultralarge (> 670 kDa) complexes (ULCs) only over a narrow molar range with an optimal ratio of PF4 to heparin of approximately 1:1. These ULCs were stable and visible by electron microscopy, but they could be dissociated into smaller complexes upon addition of heparin. ULCs formed inefficiently when PF4 was incubated with low-molecular-weight heparin, and none formed with the pentasaccharide fondaparinux sodium. In addition, mutation studies showed that formation of ULCs depended on the presence of PF4 tetramers. The ULCs were more reactive as determined by their capacity to bind to a HITT-like monoclonal antibody and showed greater capacity to promote platelet activation in an antibody- and FcγRIIA-dependent manner than were the smaller complexes. The capacity of PF4 to form ULCs composed of multiple PF4 tetramers arrayed in a lattice with several molecules of UFH may play a fundamental role in autoantibody formation, antibody-dependent platelet activation, and the propensity for thrombosis in patients with HITT.
Expression of the AID protein in normal and neoplastic B cells
Authors: Pasqualucci Laura , Guglielmino Roberta , Houldsworth Jane , Mohr Jessica , Aoufouchi Said , Polakiewicz Roberto , Chaganti R. S. K. , Dalla-Favera Riccardo
Published: August 2004

Somatic hypermutation (SHM) targets primarily the immunoglobulin variable region (IgV) genes in germinal center (GC) B cells, thereby allowing antibody affinity maturation. A malfunction of SHM, termed aberrant somatic hypermutation (ASHM), was found in about 50% of diffuse large B-cell lymphomas (DLBCLs), leading to mutations in the 5′ sequences of multiple genes, including oncogenes. Although the SHM mechanism is largely unknown, it was shown to require the activation-induced cytidine deaminase (AID) gene. AID mRNA is expressed in GC B cells and GC-derived lymphomas, but the pattern of expression of the AID protein is not known. Using 2 specific antibodies, here we show that the AID protein can be detected in GC centroblasts and their transformed counterpart (Burkitt lymphoma) but not in pre-GC B cells and post-GC neoplasms, including B-cell chronic lymphocytic leukemia and multiple myeloma. DLBCLs displayed variable levels of AID expression, which did not correlate with IgV ongoing hypermutation, ASHM, or disease subtype. Finally, both in normal and malignant B cells the AID protein appeared predominantly localized in the cytoplasm. These results indicate that the AID protein is specifically expressed in normal and transformed GC B cells; nonetheless, its predominantly cytoplasmic localization suggests that additional mechanisms may regulate its function and may be altered during lymphomagenesis. (Blood. 2004;104:3318-3325)
BCR/ABL oncogenic kinase promotes unfaithful repair of the reactive oxygen species–dependent DNA double-strand breaks
Authors: Nowicki Michal O. , Falinski Rafal , Koptyra Mateusz , Slupianek Artur , Stoklosa Tomasz , Gloc Ewa , Nieborowska-Skorska Margaret , Blasiak Janusz , Skorski Tomasz
Published: August 2004

The oncogenic BCR/ABL tyrosine kinase induces constitutive DNA damage in Philadelphia chromosome (Ph)-positive leukemia cells. We find that BCR/ABL-induced reactive oxygen species (ROSs) cause chronic oxidative DNA damage resulting in double-strand breaks (DSBs) in S and G2/M cell cycle phases. These lesions are repaired by BCR/ABL-stimulated homologous recombination repair (HRR) and nonhomologous end-joining (NHEJ) mechanisms. A high mutation rate is detected in HRR products in BCR/ABL-positive cells, but not in the normal counterparts. In addition, large deletions are found in NHEJ products exclusively in BCR/ABL cells. We propose that the following series of events may contribute to genomic instability of Ph-positive leukemias: BCR/ABL → ROSs → oxidative DNA damage → DSBs in proliferating cells → unfaithful HRR and NHEJ repair.
Sensitivity of oncogenic KIT mutants to the kinase inhibitors MLN518 and PD180970
Authors: Corbin Amie S. , Griswold Ian J. , La Rosée Paul , Yee Kevin W. H. , Heinrich Michael C. , Reimer Corinne L. , Druker Brian J. , Deininger Michael W. N.
Published: August 2004

Oncogenic mutations of the receptor tyrosine kinase KIT occur in gastrointestinal stromal tumors (GISTs), some cases of acute myelogenous leukemia (AML), and systemic mastocytosis (SM). GISTs commonly contain mutations of the KIT juxtamembrane region while SM and AML harbor active site KIT mutations. Imatinib, which potently inhibits juxtamembrane mutants, is effective for the treatment of GISTs but has no activity against active site mutants. We analyzed the inhibitory potential of 2 small molecule inhibitors, MLN518 and PD180970, against different classes of KIT mutants. Both compounds inhibit the growth of cell lines expressing juxtamembrane mutant KIT. MLN518 additionally targets active site mutant cell lines, inhibiting cell proliferation, KIT, and signal transducer and activator of transcription-3 (Stat3) phosphorylation and inducing apoptosis at concentrations that may be clinically achievable. As phase 1 clinical trials of MLN518 in AML have shown little toxicity, our data suggest MLN518 is a promising candidate for the treatment of SM or AML with KIT mutations.
Allogeneic hematopoietic cell transplantation after fludarabine and 2 Gy total body irradiation for relapsed and refractory mantle cell lymphoma
Authors: Maris Michael B. , Sandmaier Brenda M. , Storer Barry E. , Chauncey Thomas , Stuart Monic Jain , Maziarz Richard T. , Agura Edward , Langston Amelia A. , Pulsipher Michael , Storb Rainer , Maloney David G.
Published: August 2004

We carried out HLA-matched related (n = 16) and unrelated (n = 17) hematopoietic cell transplantation (HCT) in 33 patients with relapsed and refractory mantle cell lymphoma after nonmyeloablative conditioning with fludarabine and 2 Gy total body irradiation. Postgrafting immunosuppression consisted of cyclosporine and mycophenolate mofetil. Fourteen patients had failed high-dose autologous HCT. Of the 33 patients studied, 31 had stable engraftment, whereas 2 patients experienced nonfatal graft rejections. The incidences of acute grades II, III, and IV, and chronic graft-versus-host disease (GVHD) were 27%, 17%, 13%, and 64%, respectively. The overall response rate in the 20 patients with measurable disease at the time of HCT was 85% (n = 17; 75% complete remissions [CR] and 10% partial remissions [PR]), whereas 3 patients had progressive disease. Only one of the 17 patients who responded and none of the 13 who received transplants in CR had disease relapse with a median follow-up of 24.6 months. Relapse and nonrelapse mortalities were 9% and 24%, respectively, at 2 years. The Kaplan-Meier probabilities of overall and disease-free survivals at 2 years were 65% and 60%, respectively. Allogeneic HCT after nonmyeloablative conditioning is a promising salvage strategy for patients with relapsed and refractory mantle cell lymphoma. The high response and low relapse rates with this approach suggest that mantle cell lymphoma is susceptible to graft-versus-tumor responses.
Similarities in transcription factor IIIC subunits that bind to the posterior regions of internal promoters for RNA polymerase III
Authors: Matsutani Sachiko
Published: August 2004

Background

In eukaryotes, RNA polymerase III (RNAP III) transcribes the genes for small RNAs like tRNAs, 5S rRNA, and several viral RNAs, and short interspersed repetitive elements (SINEs). The genes for these RNAs and SINEs have internal promoters that consist of two regions. These two regions are called the A and B blocks. The multisubunit transcription factor TFIIIC is required for transcription initiation of RNAP III; in transcription of tRNAs, the B-block binding subunit of TFIIIC recognizes a promoter. Although internal promoter sequences are conserved in eukaryotes, no evidence of homology between the B-block binding subunits of vertebrates and yeasts has been reported previously.

Results

Here, I reported the results of PSI-BLAST searches using the B-block binding subunits of human and Shizosacchromyces pombe as queries, showing that the same Arabidopsis proteins were hit with low E-values in both searches. Comparison of the convergent iterative alignments obtained by these PSI-BLAST searches revealed that the vertebrate, yeast, and Arabidopsis proteins have similarities in their N-terminal one-third regions. In these regions, there were three domains with conserved sequence similarities, one located in the N-terminal end region. The N-terminal end region of the B-block binding subunit of Saccharomyces cerevisiae is tentatively identified as a HMG box, which is the DNA binding motif. Although I compared the alignment of the N-terminal end regions of the B-block binding subunits, and their homologs, with that of the HMG boxes, it is not clear whether they are related.

Conclusion

Molecular phylogenetic analyses using the small subunit rRNA and ubiquitous proteins like actin and α-tubulin, show that fungi are more closely related to animals than either is to plants. Interestingly, the results obtained in this study show that, with respect to the B-block binding subunits of TFIIICs, animals appear to be evolutionarily closer to plants than to fungi.
Towards the development of a DNA-sequence based approach to serotyping of Salmonella enterica
Authors: Mortimer Chloe KB , Peters Tansy M , Gharbia Saheer E , Logan Julie MJ , Arnold Catherine
Published: August 2004

Background

The fliC and fljB genes in Salmonella code for the phase 1 (H1) and phase 2 (H2) flagellin respectively, the rfb cluster encodes the majority of enzymes for polysaccharide (O) antigen biosynthesis, together they determine the antigenic profile by which Salmonella are identified. Sequencing and characterisation of fliC was performed in the development of a molecular serotyping technique.

Results

FliC sequencing of 106 strains revealed two groups; the g-complex included those exhibiting "g" or "m,t" antigenic factors, and the non-g strains which formed a second more diverse group. Variation in fliC was characterised and sero-specific motifs identified. Furthermore, it was possible to identify differences in certain H antigens that are not detected by traditional serotyping. A rapid short sequencing assay was developed to target serotype-specific sequence motifs in fliC. The assay was evaluated for identification of H1 antigens with a panel of 55 strains.

Conclusion

FliC sequences were obtained for more than 100 strains comprising 29 different H1 alleles. Unique pyrosequencing profiles corresponding to the H1 component of the serotype were generated reproducibly for the 23 alleles represented in the evaluation panel. Short read sequence assays can now be used to identify fliC alleles in approximately 97% of the 50 medically most important Salmonella in England and Wales. Capability for high throughput testing and automation give these assays considerable advantages over traditional methods.
Primary care follow up of patients discharged from the emergency department: a retrospective study
Authors: Vinker Shlomo , Kitai Eliezer , Or Yaacov , Nakar Sasson
Published: August 2004

Background

The visit to the emergency department (ED) constitutes a brief, yet an important point in the continuum of medical care. The aim of our study was to evaluate the continuity of care of adult ED visitors.

Methods

We retrospectively reviewed all ED discharge summaries for over a month 's period. The ED chart, referral letter and the patient's primary care file were reviewed. Data collected included: age, gender, date and hour of ED visit, documentation of ED referral and ED discharge letter in the primary care file.

Results

359 visits were eligible for the study. 192 (53.5%) of the patients were women, average age 54.1 ± 18.7 years (mean ± SD). 214 (59.6%) of the visits were during working hours of primary care clinics ("working hours"), while the rest were "out of hours" visits. Only 196 (54.6%) of patients had a referral letter, usually from their family physician. A third (71/214) of "working hours" visits were self referrals, the rate rose to 63.5% (92/145) of "out of hours" visits (p < 0.0001). The ED discharge letter was found in 50% (179/359) of the primary care files. A follow-up visit was documented in only 31% (111/359). Neither follow up visit nor discharge letter were found in 43% of the files (153/359).

Conclusions

We have found a high rate of ED self referrals throughout the day together with low documentation rates of ED visits in the primary care charts. Our findings point to a poor continuity of care of ED attendees.
The effect of hypertensive disorders in pregnancy on small for gestational age and stillbirth: a population based study
Authors: Allen Victoria M , Joseph KS , Murphy Kellie E , Magee Laura A , Ohlsson Arne
Published: August 2004

Background

Hypertensive disorders in pregnancy are leading causes of maternal, fetal and neonatal morbidity and mortality worldwide. However, studies attempting to quantify the effect of hypertension on adverse perinatal outcomes have been mostly conducted in tertiary centres. This population-based study explored the frequency of hypertensive disorders in pregnancy and the associated increase in small for gestational age (SGA) and stillbirth.

Methods

We used information on all pregnant women and births, in the Canadian province of Nova Scotia, between 1988 and 2000. Pregnancies were excluded if delivery occurred < 20 weeks, if birthweight was < 500 grams, if there was a high-order multiple pregnancy (greater than twin gestation), or a major fetal anomaly.

Results

The study population included 135,466 pregnancies. Of these, 7.7% had mild pregnancy-induced hypertension (PIH), 1.3% had severe PIH, 0.2% had HELLP (hemolysis, elevated liver enzymes, low platelets), 0.02% had eclampsia, 0.6% had chronic hypertension, and 0.4% had chronic hypertension with superimposed PIH. Women with any hypertension in pregnancy were 1.6 (95% CI 1.5–1.6) times more likely to have a live birth with SGA and 1.4 (95% CI 1.1–1.8) times more likely to have a stillbirth as compared with normotensive women. Adjusted analyses showed that women with gestational hypertension without proteinuria (mild PIH) and with proteinuria (severe PIH, HELLP, or eclampsia) were more likely to have infants with SGA (RR 1.5, 95% CI 1.4–1.6 and RR 3.2, 95% CI 2.8–3.6, respectively). Women with pre-existing hypertension were also more likely to give birth to an infant with SGA (RR 2.5, 95% CI 2.2–3.0) or to have a stillbirth (RR 3.2, 95% CI 1.9–5.4).

Conclusions

This large, population-based study confirms and quantifies the magnitude of the excess risk of small for gestational age and stillbirth among births to women with hypertensive disease in pregnancy.
Genome-wide array comparative genomic hybridization analysis reveals distinct amplifications in osteosarcoma
Authors: Man Tsz-Kwong , Lu Xin-Yan , Jaeweon Kim , Perlaky Laszlo , Harris Charles P , Shah Shishir , Ladanyi Marc , Gorlick Richard , Lau Ching C , Rao Pulivarthi H
Published: August 2004

Background

Osteosarcoma is a highly malignant bone neoplasm of children and young adults. It is characterized by extremely complex karyotypes and high frequency of chromosomal amplifications. Currently, only the histological response (degree of necrosis) to therapy represent gold standard for predicting the outcome in a patient with non-metastatic osteosarcoma at the time of definitive surgery. Patients with lower degree of necrosis have a higher risk of relapse and poor outcome even after chemotherapy and complete resection of the primary tumor. Therefore, a better understanding of the underlying molecular genetic events leading to tumor initiation and progression could result in the identification of potential diagnostic and therapeutic targets.

Methods

We used a genome-wide screening method – array based comparative genomic hybridization (array-CGH) to identify DNA copy number changes in 48 patients with osteosarcoma. We applied fluorescence in situ hybridization (FISH) to validate some of amplified clones in this study.

Results

Clones showing gains (79%) were more frequent than losses (66%). High-level amplifications and homozygous deletions constitute 28.6% and 3.8% of tumor genome respectively. High-level amplifications were present in 238 clones, of which about 37% of them showed recurrent amplification. Most frequently amplified clones were mapped to 1p36.32 (PRDM16), 6p21.1 (CDC5L, HSPCB, NFKBIE), 8q24, 12q14.3 (IFNG), 16p13 (MGRN1), and 17p11.2 (PMP22 MYCD, SOX1,ELAC27). We validated some of the amplified clones by FISH from 6p12-p21, 8q23-q24, and 17p11.2 amplicons. Homozygous deletions were noted for 32 clones and only 7 clones showed in more than one case. These 7 clones were mapped to 1q25.1 (4 cases), 3p14.1 (4 cases), 13q12.2 (2 cases), 4p15.1 (2 cases), 6q12 (2 cases), 6q12 (2 cases) and 6q16.3 (2 cases).

Conclusions

This study clearly demonstrates the utility of array CGH in defining high-resolution DNA copy number changes and refining amplifications. The resolution of array CGH technology combined with human genome database suggested the possible target genes present in the gained or lost clones.