bluuebunny/crossref_metadata_2025 huggingface dataset:
Functional inhibitory human leucocyte antigen class I receptors on natural killer (NK) cells in patients with chronic NK lymphocytosis
Authors: Warren Hilary S. , Christiansen Frank T. , Witt Campbell S.
Published: May 2003

Summary. Chronic natural killer (NK) lymphocytosis is a rare disorder characterized by an indolent clinical course. Despite high NK cell numbers, many patients present with only mild clinical symptoms, and are often asymptomatic. NK cells are equipped with a range of receptors that bind human leucocyte antigen (HLA)‐class I molecules. The killer immunoglobulin‐like receptors (KIR, CD158) bind groups of HLA alleles, the CD94/NKG2 receptors bind HLA‐E, and the CD85j (ILT2, LIR‐1) receptor binds to the relatively non‐polymorphic α3 domain of HLA molecules. Inhibitory HLA class I receptors silence NK cells against cells expressing normal levels of HLA class I. Analysis of NK cells in six patients with chronic NK lymphocytosis revealed a high level of the inhibitory CD94/NKG2A receptor on all NK cells. In four patients, KIR were absent, in one patient a single KIR was expressed in the absence of self‐ligand, and in one patient CD85j and multiple KIR were expressed. Cytotoxicity assays demonstrated that all HLA class I receptors were functional. The ability of monoclonal antibodies to block the receptors and allow killing of autologous target cells established that both receptor and ligand expression were adequate for inhibitory function. We propose that the silent behaviour of NK cells in patients with chronic NK lymphocytosis is due to effective inhibitory HLA class I receptors.
Thalidomide and dexamethasone for resistant multiple myeloma
Authors: Anagnostopoulos Athanasios , Weber Donna , Rankin Kim , Delasalle Kay , Alexanian Raymond
Published: May 2003

Summary.  Between November 1998 and April 2000, the combination of thalidomide and dexamethasone was evaluated in 47 consecutive patients with multiple myeloma that was resistant to prior high‐dose dexamethasone‐based therapies. Remission was observed in 22 patients (47%), including six patients with complete remission. Side‐effects were frequent, mild and usually reversible, but deep vein thrombosis occurred in 8% of patients. Survival and remission times were longer among patients treated for previous resistant disease rather than for resistant relapse. This experience supports the use of thalidomide–dexamethasone in myeloma patients with resistant disease and justifies further trials in newly diagnosed patients.
Prevalence and prognostic significance of sMUC‐1 levels in plasma cell dyscrasias
Authors: Luminari Stefano , Goldaniga Maria , Ceccherelli Fulvia , Guffanti Andrea , Bombardieri Emilio , Marcheselli Raffaella , Cro Lilla , Colombi Mariangela , Federico Massimo , Baldini Luca
Published: May 2003

Summary. High serum Mucin‐1 (sMUC‐1) levels have been shown in patients with adenocarcinoma and multiple myeloma (MM). We evaluated sMUC‐1 levels in 76 patients with MM, 6 with plasma cells leukaemia (PCL) and 89 with monoclonal gammopathy of undetermined significance, to establish prevalence data and verify its possible prognostic role. Of the 171 patients, 27 [16%; 95% confidence interval (CI): 10–21%] had high sMUC‐1 levels compared with healthy subjects (1·5%; 95% CI: 0–4%). Elevated sMUC‐1 levels in MM and PCL patients correlated with anaemia and elevated serum lactate dehydrogenase levels; these patients showed a shorter survival than those with normal sMUC‐1 levels (median overall survival: 25 vs. 49 months, P = 0·003).
Venous thromboembolism associated with the management of acute thrombotic thrombocytopenic purpura
Authors: Yarranton Helen , Cohen Hannah , Pavord Sue R. , Benjamin Sylvia , Hagger Diana , Machin Samuel J.
Published: May 2003

Summary. Venous thromboembolism (VTE) is not a feature of thrombotic thrombocytopenic purpura (TTP), but there has been a recent report of VTE in association with plasma exchange (PEX) treatment for TTP using the solvent detergent (SD) plasma, PLAS+®SD. We reviewed the occurrence of VTE in 68 consecutive patients with TTP (25 men, 43 women). Eight documented VTE events [six deep venous thromboses (DVTs), three pulmonary emboli] were identified in seven patients (all female) during PEX therapy. All six DVTs were associated with central lines at the site of thrombosis. Other known precipitating factors included pregnancy, immobility, obesity and factor V Leiden heterozygosity. VTE occurred at a mean of 53 d following the first PEX. The European SD plasma, Octaplas® was the last plasma to be used in PEX prior to the VTE in 7/8 events. This is the first report of VTE following Octaplas® infusion. VTE is a multifactorial disease and, although several known precipitating factors were present in all patients in this study, the use of large volumes of SD plasma in PEX may be an additional risk factor. We recommend prevention of VTE with graduated elastic compression stockings (class I) at diagnosis and prophylactic low‐molecular‐weight heparin once the platelet count rises above 50 × 109/l.
Activation of the Hypothalamic Arcuate Nucleus Predicts the Anorectic Actions of Ciliary Neurotrophic Factor and Leptin in Intact and Gold Thioglucose‐Lesioned Mice
Authors: Anderson K. D. , Lambert P. D. , Corcoran T. L. , Murray J. D. , Thabet K. E. , Yancopoulos G. D. , Wiegand S. J.
Published: May 2003

Similar to leptin, ciliary neurotrophic factor (CNTF) suppresses appetite and selectively reduces body fat in leptin‐deficient ob/ob mice. To assess the relative importance of specific regions of the hypothalamus in mediating these effects, we administered a CNTF analogue (CNTFAx15) or leptin to mice made obese by administration of gold thioglucose (GTG), which destroys a well‐defined portion of the medial basal hypothalamus. CNTFAx15 treatment reduced appetite and body weight in obese GTG‐lesioned C57BL/6 mice, whereas leptin failed to effect similar changes regardless of whether treatment was initiated before or after the lesioned mice had become obese. Because leptin does not reduce food intake or body weight in most forms of obesity (a condition termed ‘leptin resistance’), we also investigated the actions of leptin in GTG‐lesioned leptin‐deficient (ob/ob) mice. By contrast to C57BL/6 mice, leptin treatment reduced food intake and body weight in GTG‐lesioned ob/ob mice, although the effect was attenuated. To further compare the neural substrates mediating the anorectic actions of leptin and CNTF, we determined the patterns of neurone activation induced by these proteins in the hypothalamus of intact and GTG‐lesioned mice by staining for phosphorylated signal transducer and activator of transcription 3 (pSTAT3). CNTFAx15 stimulated robust pSTAT3 signalling in neurones of the medial arcuate nucleus in both intact and lesioned C57BL/6 and ob/ob mice. Leptin administration stimulated pSTAT3 signalling in only a few neurones of the medial arcuate nucleus in intact or lesioned C57BL/6 mice, but elicited a robust response in intact or lesioned ob/ob mice. By contrast to CNTFAx15, leptin treatment also resulted in prominent activation of STAT3 in several areas of the hypothalamus outside the medial arcuate nucleus. This leptin‐induced pSTAT3 signal was at least as prominent in intact and GTG‐lesioned C57BL/6 mice as it was in ob/ob mice, and thus was not correlated with appetite suppression or weight loss. These results indicate that the medial arcuate nucleus is a key mediator of appetite suppression and weight loss produced by CNTF and leptin, whereas GTG‐vulnerable regions play a role only in leptin‐induced weight loss. Other regions of hypothalamus in which pSTAT3 signal is induced by leptin may regulate energy metabolism through mechanisms other than appetite reduction.
Hypothalamic‐Pituitary‐Adrenal Responses to Centrally Administered Orexin‐A are Suppressed in Pregnant Rats
Authors: Brunton P. J. , Russell J. A.
Published: May 2003

Orexins are hypothalamic neuropeptides that stimulate arousal and food intake but also activate the hypothalamic‐pituitary‐adrenal (HPA) axis. During late pregnancy in the rat, the responsiveness of the HPA axis to stressors is attenuated, and thus we investigated HPA axis responses to centrally administered orexin‐A during pregnancy. Intracerebroventricular injection of orexin‐A (0.5 µg, 140 pmol) significantly increased plasma adrenocorticotropic hormone and corticosterone concentration within 10 min in virgin female Sprague‐Dawley rats, but had no effect in day 21 pregnant rats. Orexin‐A significantly increased corticotropin‐releasing hormone (CRH) mRNA expression, measured by in situ hybridization, in the paraventricular nucleus (PVN) of the virgin group but not in the pregnant group. Thus, the responsiveness of PVN CRH neurones to orexin‐A, and hence the pituitary‐adrenal axis, is markedly reduced in pregnancy. This may favour anabolic adaptations in pregnancy.
Nitric Oxide Produced by a Novel Nitric Oxide Synthase Isoform is Necessary for Gonadotropin‐Releasing Hormone‐Induced Growth Hormone Secretion Via a cGMP‐Dependent Mechanism
Authors: Uretsky A. D. , Weiss B. L. , Yunker W. K. , Chang J. P.
Published: May 2003

The involvement of nitric oxide (NO) in the regulation of goldfish growth hormone (GH) secretion was further characterized using primary cultures of dispersed goldfish pituitary cells. Western blots revealed the presence of an inducible nitric oxide synthase (iNOS)‐like protein of approximately 120 kDa in cytosol/plasma membrane extracts. By contrast, brain NOS‐immunoreactive proteins of approximately 120–140 kDa were occasionally detected in a cytoskeleton/organelle fraction but were absent from cytosol/plasma membrane extracts. The NO donor sodium nitroprusside (SNP) acutely increased GH secretion but this response was not observed in the presence of either a NO scavenger (PTIO) or a soluble guanylate cyclase inhibitor (ODQ). SNP also significantly increased the levels of cyclic (c)GMP in somatotrope‐enriched cell populations. Treatments with 1400W (iNOS inhibitor), PTIO and rutin hydrate (NO scavengers) and ODQ abolished the acute GH‐release response to two endogenous gonadotropin‐releasing hormones (GnRH). 1400W, rutin hydrate, PTIO and ODQ alone did not significantly alter basal GH secretion. Together, these results establish that an iNOS‐like peptide is constitutively present in the pituitary of the goldfish. Furthermore, these data suggest that NO, most likely through the generation of cGMP, is a necessary signal transduction component of GnRH‐induced GH secretion.
Mitochondrial Benzodiazepine Receptors in the Ventral Tegmental Area Modulate Sexual Behaviour of Cycling or Hormone‐Primed Hamsters
Authors: Frye C. A. , Petralia S. M.
Published: May 2003

Hamsters are highly dependent upon the central actions of progesterone (P4) for facilitation of sexual behaviour. In the ventral tegmental area (VTA), P4 has actions through its neurosteroid metabolite 5α‐pregnan‐3α‐ol‐20‐one (3α,5α‐THP). The effects of enhancing or inhibiting neurosteroidogenesis (and thereby 3α,5α‐THP concentrations), through manipulations of mitochondrial benzodiazepine receptors, in the VTA on socio‐sexual behaviour of female hamsters were examined. Intact, naturally receptive hamsters and ovariectomized (OVX), hormone‐primed hamsters were unilaterally infused via chronic guide cannula to the VTA with the mitochondrial benzodiazepine receptor antagonist 1‐(2‐chlorophenyl)‐N‐methyl‐N‐(1‐methylpropyl)‐3‐isoquinolinecarboximide (PK‐11195) or the mitochondrial benzodiazepine receptor agonist, N,N‐dihexyl‐2‐(4‐fluorophenyl)indole‐30‐acetamide (FGIN 1‐27) and tested for sexual responsiveness and lordosis. PK‐11195 (5.6, 11.2 or 22.4 nm) to the VTA attenuated sexual responsiveness of naturally receptive or oestradiol benzoate (EB) + P4‐primed hamsters compared to vehicle. In addition, FGIN 1‐27 (11.4 nm) infusions to the VTA increased sexual responsiveness and lordosis of cycling or OVX, EB + P4‐primed hamsters, compared to vehicle infusions. In OVX, EB + P4‐primed hamsters, decrements in sexual responsiveness produced by VTA infusions of PK‐11195 (5.6 nm) were attenuated by VTA infusions of 3α,5α‐THP. VTA infusions of PK‐11195 (5.6 nm) or FGIN 1‐27 (11.4 nm), respectively, decreased and increased midbrain levels of 3α,5α‐THP compared to each other. Together, these findings indicate that manipulating actions of mitochondrial benzodiazepine receptors in the VTA can augment and inhibit neurosteroidogenesis and sexual responsiveness of hormone‐primed and naturally receptive hamsters.
Links Between the Appetite Regulating Systems and the Neuroendocrine Hypothalamus: Lessons from the Sheep
Authors: Henry B. A.
Published: May 2003

The hypothalamus is integral to the regulation of energy homeostasis and the secretion of hormones from the pituitary gland. Consequently, hypothalamic systems may have a dual purpose in regulating both neuroendocrine function and appetite. To date, most studies investigating the interface between appetite and hormone secretion have been performed in rats or mice that have been acutely fasted or baring a genetic abnormality causing either obesity or aphagia. By contrast, various physiological models, including chronic food‐restriction or photoperiodically driven changes in voluntary food intake, add further perspective to the issue. In this regard, sheep provide an innovative model whereby long‐term changes in body weight or extended feeding rhythms can be investigated. This review compares and contrasts data obtained in different species with regard to the neuroendocrinology of appetite, and discusses the benefits and knowledge gained from using various nonrodent models with a particular emphasis on a ruminant species.
The structure of the helically perturbed flagellar filament of Pseudomonas rhodos: implications for the absence of the outer domain in other complex flagellins and for the flexibility of the radial spokes
Authors: Cohen‐Krausz Sara , Trachtenberg Shlomo
Published: May 2003

Bacterial flagella, the organelles of motility, are commonly divided into two classes: ‘plain’ and ‘complex’. The complex filaments are pairwise, helically perturbed forms of the plain filaments and have been reported to occur only in Rhizobium and Pseudomonas. Previously, we reconstructed and analysed the structure of the complex filaments of Rhizobium lupini H13‐3 and determined their unique symmetry and origin of the perturbations (Trachtenberg et al., 1986, J Mol Biol 190: 569–576; 1987, 195: 603–620; 1998, 276: 759–773; Cohen‐Krausz and Trachtenberg, 1998, J Struct Biol 122: 267–282). Here, we analyse the structure of the flagellar filament of the other known complex filament, that of Pseudomonas rhodos, as reconstructed from electron microscope images. Compared with the filament of R. lupini, the  filament of P. rhodos is more flexible, as implied from high‐intensity darkfield light microscopy and, although constructed from flagellins of higher molecular weights (59 versus 41 kDa), has similar symmetry. Using cryonegative stained specimens and low‐dose, field emission electron microscopy, we reconstructed and averaged 158 filaments each containing 170 statistically significant layer lines. The three‐dimensional density maps of P. rhodos clearly suggest, when compared with those of R. lupini and the right‐handed Salmonella typhimurium SJW1655, that R. lupini is missing the outer flagellin domain (D3), that the interior of the complex filament is rather similar to that of the plain filament and that the radial spokes (connecting domains D0 and D1), present in individual density maps, average out because of their variability and implied flexibility. Extending the three‐start grooves and ridges on the propeller's surface, in the form of an Archimedean screw, may further improve the motility of the cell in viscous environments.
The DNA excision repair system of the highly radioresistant bacterium Deinococcus radiodurans is facilitated by the pentose phosphate pathway
Authors: Zhang Y.‐M. , Liu J.‐K. , Wong T.‐Y.
Published: May 2003

Deinococcus radiodurans is highly resistant to radiation and mutagenic chemicals. Mutants defective in the putative glucose‐6‐phosphate dehydrogenase gene (zwf–) and the aldolase gene (fda–) were generated by homologous recombination. These mutants were used to test the cells’ resistance to agents that cause dimer formation and DNA strand breaks. The zwf – mutants were more sensitive to agents that induce DNA excision repair, such as UV irradiation and H2O2, but were as resistant to DNA strand break‐causing agents such as methylmethanesulphonic acid (MMS) and mitomycin C (MMC) as the wild‐type cells. Analysis of the cytoplasmic fraction of zwf– cells showed that the concentrations of inosine monophosphate (IMP) and uridine monophosphate (UMP) were only 30% of those found in the wild‐type cells. The fda– mutants were slightly more resistant to UV light and H2O2. Results suggested that the deinococcal pentose phosphate pathway augmented the DNA excision repair system by providing cells with adequate metabolites for the DNA mismatch repair.
Tracing pathways of transport protein evolution
Authors: Saier Milton H.
Published: May 2003

We have conducted bioinformatic analyses of integral membrane transport proteins belonging to dozens of families. These families rarely include proteins that function in a capacity other than transport. Many transporters have arisen by intragenic duplication, triplication and quadruplication events, in which the numbers of transmembrane α‐helical hydrophobic segments (TMSs) have increased. The elements multiplied may encode two, three, four, five, six, 10 or 12 TMSs and gave rise to proteins with four, six, seven, eight, nine, 10, 12, 20, 24 and 30 TMSs. Gene fusion, splicing, deletion and insertion events have also contributed to protein topological diversity. Amino acid substitutions have allowed membrane‐embedded domains to become hydrophilic domains and vice versa. Some evidence suggests that amino acid substitutions occurring over evolutionary time may in some cases have drastically altered protein topology. The results summarized in this microreview establish the independent origins of many transporter families and allow postulation of the specific pathways taken for their appearance.
The use of flow cytometry to detect expression of subunits encoded by 11 Salmonella enterica serotype Typhimurium fimbrial operons
Authors: Humphries Andrea D. , Raffatellu Manuela , Winter Sebastian , Weening Eric H. , Kingsley Robert A. , Droleskey Robert , Zhang Shuping , Figueiredo Josely , Khare Sangeeta , Nunes Jairo , Adams L. Garry , Tsolis Renée M. , Bäumler Andreas J.
Published: May 2003

The Salmonella enterica serotype Typhimurium (S. Typhimurium) genome contains 13 putative fimbrial operons termed agf (csg), fim, pef, lpf, bcf, saf, stb, stc, std, stf, sth, sti and stj. Evidence for in vitro expression of fimbrial proteins encoded by these operons is currently only available for agf, fim and pef. We raised antisera against putative major fimbrial subunits of S. Typhimurium, including AgfA, FimA, PefA, LpfA, BcfA, StbA, StcA, StdA, StfA, SthA and StiA. Elaboration of StcA on the bacterial surface could be detected by flow cytometry and immunoelectron microscopy after expression of the cloned stcABCD operon from a heterologous T7 promoter in Escherichia coli. To study the expression of fimbrial antigens in S. Typhimurium by flow cytometry, we constructed strains carrying deletions of agfAB, pefBACDI, lpfABCDE, bcfABCDEFG, stbABCD, stcABC, stdAB, stfACDEFG, sthABCDE or stiABCDE. Using these deletion mutants for gating, expression of fimbrial antigens was measured by flow cytometry in cultures grown in vitro or in samples recovered 8 h after infection of bovine ligated ileal loops with S. Typhimurium. FimA was the only fimbrial antigen expressed by S. Typhimurium after static growth in Luria–Bertani (LB) broth. Injection of static LB broth cultures of S. Typhimurium into bovine ligated ileal loops resulted in the expression of BcfA, FimA, LpfA, PefA, StbA, StcA, StdA, StfA and StiA. These data show that in vivo growth conditions drastically alter the repertoire of fimbrial antigens expressed in S. Typhimurium.
A reporter gene system for the hyperthermophilic archaeon Sulfolobus solfataricus based on a selectable and integrative shuttle vector
Authors: Jonuscheit Melanie , Martusewitsch Erika , Stedman Kenneth M. , Schleper Christa
Published: May 2003

Sulfolobus solfataricus has developed into an important model organism for molecular and biochemical studies of hyperthermophilic archaea. Although a number of in vitro systems have been established for the organism, efficient tools for genetic manipulations have not yet been available for any hyperthermophile. In this work, we have developed a stable and selectable shuttle vector based on the virus SSV1 of Sulfolobus shibatae. We have introduced pUC18 for propagation in Escherichia coli and the genes pyrEF coding for orotidine‐5′‐monophosphate pyrophosphorylase and orotidine‐5′‐monophosphate decarboxylase of Sulfolobus solfataricus as selectable marker to complement pyrimidine auxotrophic mutants. Furthermore, the beta‐galactosidase gene (lacS) was introduced into this vector as a reporter under the control of the strong and heat‐inducible promoter of the Sulfolobus chaperonin (thermosome). After transformation of a S. solfataricus pyrEF/lacS double mutant, the vector was found to reside as a single‐copy vector, stably integrated into the host chromosome via the site‐specific recombination system of SSV1. Specific beta‐galactosidase activities in transformants were found to be fourfold higher than in wild‐type S. solfataricus cells, and increased to more than 10‐fold after heat shock. Greatly increased levels of lacS mRNA were detected in Northern analyses, demonstrating that this reporter gene system is suitable for the study of regulated promoters in Sulfolobus and that the vector can also be used for the high‐level expression of genes from hyperthermophilic archaea.
Ribosome bypassing elicited by tRNA depletion
Authors: Lindsley Dale , Gallant Jonathan , Guarneros Gabriel
Published: May 2003

Ribosome bypassing refers to the ability of the ribosome::peptidyl‐tRNA complex to slide down the message without translation to a site several or dozens of nucleotides downstream and resume protein chain elongation there. The product is an isoform of a protein with a ‘coding’ gap corresponding to the region of the message which was bypassed. Previous work showed that ribosome bypassing was strongly stimulated at ‘hungry’ codons calling for a tRNA whose aminoacylation was limited. We have now used the ‘minigene’ phenomenon to ascertain whether depletion of the pool of specific isoacceptors has a similar effect. High level expression of plasmid‐borne minigenes results in the sequestration as peptidyl‐tRNA of tRNA cognate to the last triplet of the minigene, thereby limiting protein synthesis for lack of the tRNA in question. We find that induction of a minigene ending in AUA stimulates bypassing at an AUA codon, but not in a control sequence with AGA at the test position; induction of a minigene ending in AGA stimulates bypassing at the latter but not the former. Induction of the AUA minigene also stimulates both leftward and rightward frameshifting at ‘shifty’ sequences containing an AUA codon. The normal, background frequency of bypassing at an AUA codon is markedly reduced by increasing the cellular level of the tRNA which reads the codon. Thus, the frequency of bypassing can be increased or decreased by lowering or raising the concentration of a relevant tRNA isoacceptor. These observations suggest that the occurrence of ribosome bypassing reflects the length of the pause at a given codon.
Translational repression mechanisms in prokaryotes
Authors: Schlax Paula Jean , Worhunsky David J.
Published: May 2003

Translational repression results from a complex choreography of macromolecular interactions interfering with the formation of translational initiation complexes. The relationship between the rate and extent of formation of these interactions to form repressed mRNA complexes determines the extent of repression. A novel analysis of repression mechanisms is presented here and it indicates that the reversibility of repressed complex formation influences the steady state balance of the distribution of translationally active and inactive complexes and therefore has an impact on the efficiency of repression. Reviewed here is evidence for three distinct translational repression mechanisms, regulating expression of the transcription factor σ32, threonine tRNA synthetase and ribosomal proteins on the α operon in Escherichia coli. Efficient regulation of expression in these systems makes use of specific mRNA structures in quite different ways.
Identification of Candida albicans genes induced during thrush offers insight into pathogenesis
Authors: Cheng Shaoji , Clancy Cornelius J. , Checkley Mary Ann , Handfield Martin , Hillman Jeffrey D. , Progulske‐Fox Ann , Lewin Alfred S. , Fidel Paul L. , Nguyen M. Hong
Published: May 2003

Candida albicans causes a wide spectrum of diseases, ranging from mucocutaneous infections like oral thrush to disseminated candidiasis. Screening for C. albicans genes expressed within infected hosts might advance understanding of candidal pathogenesis, but is impractical using existing techniques. In this study, we used an antibody‐based strategy to identify C. albicans genes expressed during thrush. We adsorbed sera from HIV‐infected patients with thrush against candidal cells grown in vitro and screened a C. albicans genomic expression library. We identified 10 genes encoding immunogenic antigens and used reverse transcription‐polymerase chain reaction to verify that they were induced within thrush pseudomembranes recovered from a patient. The in vivo induced genes are involved in diverse functions, including regulation of yeast‐hyphal morphogenesis, adhesion to host cells, nutrient uptake, phospholipid biosynthesis and amino acid catabolism. Four genes encode known virulence determinants (HWP1, CST20, CPP1 and RBF1). Another gene, LPD1, for which a role in candidal pathogenesis is unknown, encodes a protein homologous to a bacterial virulence determinant. Most importantly, disruption of CaNOT5, a newly identified gene, conferred defects in morphogenesis, decreased adherence to human buccal epithelial cells and attenuated mortality during murine disseminated candidiasis, proving that our strategy can identify genes encoding novel virulence determinants.
Prevalence and Economic Importance of Cystic Echinococcosis in Slaughtered Ruminants in Burdur, Turkey1
Authors: Umur S. , Kaaden O.‐R.
Published: May 2003

This study was conducted between April 2000 and March 2001, in 12‐month period. During the study, local slaughterhouses were visited periodically for 1 year to examine the internal organs (livers, lungs, spleens and hearts) for the presence of cysts and total 1355 cattle, 218 sheep and 104 goats were examined for the cystic echinococcosis (CE). It was found that 13.5% of cattle, 26.6% of sheep and 22.1% of goats were infected with this disease. While cysts in cattle (P < 0.001) and goats (P > 0.05) were found mostly in lungs (88.5 and 82.6%, respectively), but they were mostly found in livers (P > 0.05) in sheep. In addition to this, three spleens and one heart in cattle were infected with CE. In this study, the prevalence of CE and the number of cysts in ruminants were found different when the cattle, sheep and goats examined were stratified based on age. The prevalence and the number of cysts increased with age approaching an asymptotic prevalence of one in the oldest animals (P < 0.05). The number of cysts in cattle, sheep and goats were increasing at a rate of 0.31, 0.63 and 0.42/year, respectively. The economic decrease in the value of the carcasses because of the discarded liver and lung as a result of CE was estimated as 1.1% ($7.5 per cattle) for cattle, 4.37% ($3.2 per sheep) for sheep and 4.26% ($2.9 per goat) for goats. The minimum total loss for all infected animals was determined to be $583 in infected animals, based on the market prices in the year 2002.
Bulk Tank Milk Analysis: Factors Associated with Appearance ofMycoplasmasp. in Milk
Authors: Fox L. K. , Hancock D. D. , Mickelson A. , Britten A. , Kaaden O.‐R.
Published: May 2003

Factors associated with the presence ofMycoplasmasp. in bulk tank milk samples were evaluated from 664 herds during 2.25 years. Milk quality components were not strongly related to the presence ofMycoplasmasp. in bulk tank milk. The presence of other contagious mastitis pathogens,Staphylococcus aureusandStreptococcus agalactiae, was also not related to the presence of mycoplasma, suggesting that the aetiology and transmission of mycoplasma mastitis were different from transmission of other contagious mastitis pathogens. The occurrence of the first isolation of mycoplasma from a bulk tank was not correlated to season of the year. Mycoplasma in bulk tank milk samples were more likely to be found in herds shipping more milk, an indirect measure of herd size. This suggests that larger herds are more likely to have mycoplasma mastitis. However, the first appearance of mycoplasma mastitis in a bulk tank sample was followed by a sample without this pathogen in more than 60% of herds.Mycoplasmasp. was not detected in any herd a year after first isolation. These findings suggest that this pathogen could be controlled and eliminated from herds.
Prominent induction of cyclin B1 in G2/M renal cancer cells with butyrolactone 1
Authors: KASUYA YUTAKA , HOSAKA YOSHIO , MATSUSHIMA HISASHI , GOTO TOSHITAKA , KITAMURA TADAICHI , OKUYAMA AKIRA
Published: May 2003

Background: Butyrolactone 1 (BL) is a cyclin dependent kinase (CDK) inhibitor derived from Aspergillus terreus. None of the present drugs are effective for the treatment of renal cell carcinoma. The use of BL is expected to promote a new type therapy of renal cancer.

Methods: We investigated three human renal cancer cell lines: ACHN, OS‐RC‐2 and RCC10RGB, using 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide (MTT) assay and two‐color flow cytometry. Simultaneous measurements of DNA content and cyclin expression allowed us to perform cell cycle specific analysis. Western blot analysis was performed using ACHN to represent cell lines.

Results: BL inhibited cell proliferation and caused cell accumulation at G2/M phase associated with the emergence of the third peak. Moreover, BL induced cyclin B1 over‐expression in G2/M cells. These changes were quite definite, whereas cyclins D1, E and A showed no changes at all. Cyclin B1 accumulation was confirmed by western blot analysis. The chronological observation revealed that the emergence of the third peak preceded the regression of the increased cyclin B1 positive G2/M cells. These results suggested that BL accelerated cyclin B1 accumulation in G2/M cells, which then shifted to G1 phase without cell division. New G1 cells started DNA synthesis most likely as endoreduplication to form the third peak and the mechanism of cyclin B1 accumulation converted into down‐regulation.

Conclusion: BL induced significant cell kinetic interference in the tested human renal carcinoma cell lines. This might indicate the possibility of a new medical treatment modality for renal cancer.
Cadmium nephrotoxicity and evacuation from the body in a rat modeled subchronic intoxication
Authors: AOYAGI TEIICHIRO , HAYAKAWA KUNIHIRO , MIYAJI KEISUKE , ISHIKAWA HIROMICHI , HATA MAKOTO
Published: May 2003

Background: Cadmium (Cd) is an important industrial pollutant, although its mechanism of toxicity has not been completely clarified. We studied Cd‐induced subchronic nephrotoxicity and the cadmium evacuation system in rats and cultured human renal tubular cells.

Methods: Male Sprague–Dawley rats were subcutaneously injected with 0.6 mg Cd/kg per day for periods of 3, 5 and 8 weeks. The concentration of Cd in urine, serum and kidneys was measured by atomic absorption spectrophotometry. Nephrotoxicity was evaluated based on the urinary concentration of β2 microglobulin (B2MG) and histopathological findings. Apoptotic cells were detected by nick‐end labeling and DNA laddering, and were based on the level of caspase‐3 activity. Cadmium‐induced toxicity was also studied in cultured human renal tubular cells.

Results: Nephrotoxicity was detected after 4 weeks of exposure to Cd, because Cd and B2MG appeared in urine. The tissue concentration of Cd increased linearly throughout the 8 weeks of exposure to Cd. The concentration of renal Cd did not change in the 3‐week exposure group, but it decreased after withdrawal of Cd in the 5‐week exposure group, suggesting an active Cd excretion mechanism started after the 4th week. The threshold Cd concentration for nephrotoxicity was 150 micrograms/gram wet tissue, at which concentration histological tubular damage started. Although the kidneys presented mainly necrosis, apoptosis was observed at weeks 4 and 5, before renal tubular necrosis occurred. In vitro DNA laddering was observed and peak caspase‐3 activity was detected when the cells were exposed to the threshold concentration of Cd.

Conclusion: Cadmium was effectively evacuated from the body by exfoliation of damaged renal tubular cells presenting focal tubular necrosis after the renal Cd concentration reached the threshold. Apoptosis may be involved in the regulation of Cd‐induced nephrotoxicity.
Significance of capsular attachment and invasion of cancer tissues in prostate cancer
Authors: TANAKA MASASHI , SUZUKI NORIYUKI , NAKATSU HIROOMI , MURAKAMI SHINO , MATSUZAKI OSAMU , SHIMAZAKI JUN
Published: May 2003

Background: There is a discrepancy in tumor node metastasis (TNM) staging of capsular attachment and invasion; the condition was classified as pT3 in 1987, then as pT2 in 1992. Because capsular finding associated with radical prostatectomy is an important prognostic factor, the present study was conducted to characterize clinicopathological states of cancer tissues attached to and invading the capsule.

Methods: Specimens removed by radical prostatectomy exhibiting pT2 or pT3 from 90 patients who did not receive any treatment before surgery were classified as Loc (24%, cancer tissues localized and apart from capsule), Inv (59%, attached to and invading but not penetrating capsule) and Pen (17%, penetrating capsule). Their clinicopathological profiles were examined.

Results: Gleason score, volume of cancer tissues, seminal vesicle invasion, positive surgical margin and regional lymph node metastasis of Inv were distributed between those of Loc and Pen. Postoperative management was decided as routine check‐up or endocrine therapy according to pathological findings. Median follow‐up was 59 months. Prostate‐specific antigen (PSA) relapse occurred in 13 patients, one of whom died of prostate cancer. The remaining of these patients lived. Rate of PSA relapse was not different between Loc and Inv, mainly due to endocrine therapy to Inv with high risk factors.

Conclusion: Pathological profile of Inv lies between those of Loc and Pen. Therefore, pT2a (1997) would be subclassified as Loc and Inv. Patients with Inv may be required to receive the respective management according to clinicopathological profile, which would be different to that of Loc.
Association of absence of intestinal oxalate degrading bacteria with urinary calcium oxalate stone formation
Authors: MIKAMI KAZUO , AKAKURA KOICHIRO , TAKEI KAZUSHIRO , UEDA TAKESHI , MIZOGUCHI KEN’ICHI , NODA MASATOSHI , MIYAKE MASAMI , ITO HARUO
Published: May 2003

Aim: Urinary concentration of oxalate is considered an important factor in the formation of renal stones. Dietary oxalate is a major contributor to urinary oxalate excretion in most individuals. Furthermore, oxalate degrading bacteria have been isolated from human feces. We investigated the significance of oxalate degrading bacteria for urinary oxalate excretion and urinary stone formation.

Methods: Twenty‐two known calcium oxalate stone‐forming patients (stone formers) and 34 healthy volunteers (non‐stone formers) were included in the study. Stool specimens were inoculated into pepton yeast glucose (PYG) medium supplemented with oxalate under anaerobic condition at 37 C for one week. After the incubation period, each colony was checked for the loss of oxalate from the culture medium. A 24‐h urine sample was collected in 43 individuals and analyzed for oxalate excretion.

Results: Twenty‐eight of 34 (82%) healthy volunteers and 10 of 22 (45%) calcium oxalate stone formers were colonized with oxalate degrading bacteria. Calcium oxalate stone formers were more frequently free of oxalate degrading bacteria (P < 0.01). Urinary excretion of oxalate in those with oxalate degrading bacteria was significantly less than in those without oxalate degrading bacteria (P < 0.05). Hyperoxaluria (> 40 mg/day) was found in four of 27 individuals (15%) with oxalate degrading bacteria compared to seven of 16 (44%) without oxalate degrading bacteria (P < 0.05), suggesting an association between the absence of oxalate degrading bacteria and the presence of hyperoxaluria.

Conclusion: The absence of oxalate degrading bacteria in the gut could promote the absorption of oxalate, thereby increasing the level of urinary oxalate excretion. The absence of oxalate degrading bacteria from the gut appears to be a risk factor for the presence of absorptive hyperoxaluria and an increased likelihood of urolithiasis.
Functional evaluation of one‐stage urethroplasty with parameatal foreskin flaps repair of hypospadias using uroflowmetry
Authors: ANWAR AHMED , KUROKAWA YASUSHI , TAKAHASHI MASAYUKI , YAMAMOTO YASUYO , KANAYAMA HIRO‐OMI , KAGAWA SUSUMU
Published: May 2003

Background: Uroflowmetry is a simple, accurate and non‐invasive test. In the present study, we aimed to determine the role of uroflowmetry in the evaluation of the functional results of one‐stage urethroplasty with parameatal foreskin flaps (OUPF) technique.

Methods: Twenty‐one children who had undergone OUPF repair at our clinic were selected. Selection criteria were that patients were toilet trained and had no fistula. Uroflowmetry was performed using a rotating disk sensor. The maximum flow rate (Qmax) and average flow rate (Qave) were plotted against body surface related flow rate nomograms. The upper 95% tolerance limits for the 5th, 10th, 15th, 20th and 25th percentiles of the normal population were used for comparison. The flow pattern was classified as bell ring, plateau or intermittent.

Results: The median age at the first uroflowmetry was 4.7 years (range 2.5–8.6) and the mean postoperative follow‐up period was 25 months (range 1–58). Twelve children had Qmax above the 25th, six between the 5th and 25th and three less than the 5th percentiles of the normal population. A normal bell‐shaped flow curve was obtained in 17 (80.6%) of the children. Of the three children with Qmax below the 5th percentile, two children had a plateau flow pattern and were found to have a urethal stricture. Dilation was performed successfully, after which the Qmax returned to the normal range and the symptoms disappeared.

Conclusion: The OUPF technique provided satisfactory functional results for hypospadias repair. We advocate the use of uroflowmetry for routine postoperative follow‐up.
Bladder smooth muscle cell phenotypic changes and implication of expression of contractile proteins (especially caldesmon) in rats after partial outlet obstruction
Authors: MATSUMOTO SEIJI , HANAI TADASHI , OHNISHI NORIO , YAMAMOTO KAZUHIKO , KURITA TAKASHI
Published: May 2003

Background: The purpose of the present study was to investigate morphological changes in bladder smooth muscle of rats with partial outlet obstruction. We investigated smooth muscle cell phenotypic changes and implication of synthetic phenotype in contractility decrease and bladder compliance after bladder outlet obstruction.

Methods: Partial bladder outlet obstruction was introduced in female rats. Bladder were removed at 1, 3, 6, 10 and 20 weeks after the obstruction. Temporal pattern of changes in bladder mass, light microscopic pathogenesis and phenotypic expression of the bladder smooth muscle cells in the electron micrographs were investigated. Expression of contractile protein was also investigated by the immunoblotting method.

Results: Marked increase in bladder mass with marked thickening of smooth muscle layer was observed at 1 week after obstruction. The ratio of myocytes exhibiting contractile and synthetic phenotypes was almost constant until 6 weeks after the obstruction, but thereafter, synthetic phenotypes gradually increased and the ratio (synthetic/contractile phenotype) was 1.5‐fold at 20 weeks after the obstruction. Caldesmon was most markedly expressed after the obstruction among contractile proteins examined by the immunoblotting method.

Conclusion: Phenotypic changes were confirmed in bladder smooth muscle, and the decrease of the ratio of contractile phenotype was observed after long‐term obstruction of the bladder outlet. Among the contractile proteins in the bladder smooth muscle cell, caldesmon was considered a reliable marker for predicting the pathogenetic conditions of the bladder.
A two‐locus model for hereditary non‐polyposis colorectal cancer in Modena, Italy
Authors: SCAPOLI C. , COLLINS A. , BENATTI P. , PERCESEPE A. , RONCUCCI L. , PONZ DE LEON M.
Published: May 2003

Complex segregation analysis was conducted in a series of patients with hereditary non‐polyposis colorectal cancer (HNPCC) ascertained through probands registered in the Cancer Registry of the Health Care District of Modena, Northern Italy. Altogether there were 125 nuclear families segregating for HNPCC, for a total of 672 individuals. The analysis favoured a two‐locus model, with both susceptibility genes rare and dominant. The gene frequency of the deleterious allele at the major locus is estimated to be low qm=0·004 and for the second locus the estimate is even lower q=0·00003. Both genes defining the two‐locus model seem to be highly penetrant. The lifetime penetrance of the abnormal gene at the major locus is estimated to be 0·73 for female, while the estimation for male is higher, 0·85.
Heterogeneous effects of natural selection on the Italian newborns
Authors: ZONTA L. A. , ASTOLFI P. , ULIZZI L.
Published: May 2003

We have studied the impact of natural selection through stillbirth on the Italian population, taking into account the socio‐economic heterogeneity of the country. The results suggest that older age at delivery and lower cultural level of the mothers, indicators of critical biological and socio‐economic conditions, even at present increase stillbirth risk. Moreover, in the less favourable environment of the southern regions, selection is still sex‐specific.
Forthcoming genetical conferences
Authors: Cerro H.
Published: May 2003

Sponsored by the Oasi Institute for Research on Mental Retardation and Brain Aging Genetics is a rapidly growing field of medical science, which reveals molecular mechanisms of biological phenomena in health and disease. For this reason, we selected the topic ‘Neurogenetic Disease: From Molecule to Patient’, for the 4th International Symposium on Brain Dysfunction to be held September 1997. Various aspects of neurogenetic diseases: phenotype, pathology, pharmacology, biochemistry, genetics, animal models, and treatment will be discussed. We hope that this international meeting will further promote research in this field in order to understand pathogenesis as well as to develop new therapeutic approaches to genetic diseases affecting the nervous system.
Neurogenesis and aging: FGF‐2 and HB‐EGF restore neurogenesis in hippocampus and subventricular zone of aged mice
Authors: Jin Kunlin , Sun Yunjuan , Xie Lin , Batteur Sophie , Mao Xiao Ou , Smelick Chris , Logvinova Anna , Greenberg David A.
Published: May 2003

Neurogenesis, which may contribute to the ability of the adult brain to function normally and adapt to disease, nevertheless declines with advancing age. Adult neurogenesis can be enhanced by administration of growth factors, but whether the aged brain remains responsive to these factors is unknown. We compared the effects of intracerebroventricular fibroblast growth factor (FGF)‐2 and heparin‐binding epidermal growth factor‐like growth factor (HB‐EGF) on neurogenesis in the hippocampal dentate subgranular zone (SGZ) and the subventricular zone (SVZ) of young adult (3‐month) and aged (20‐month) mice. Neurogenesis, measured by labelling with bromodeoxyuridine (BrdU) and by expression of doublecortin, was reduced by ∼90% in SGZ and by ∼50% in SVZ of aged mice. HB‐EGF increased BrdU labelling in SGZ at 3 months by ∼60% and at 20 months by ∼450%, which increased the number of BrdU‐labelled cells in SGZ of aged mice to ∼25% of that in young adults. FGF‐2 also stimulated BrdU labelling in SGZ, by ∼25% at 3 months and by ∼250% at 20 months, increasing the number of newborn neurones in older mice to ∼20% of that in younger mice. In SVZ, HB‐EGF and FGF‐2 increased BrdU incorporation by ∼140% at 3 months and ∼170% at 20 months, so the number of BrdU‐labelled cells was comparable in untreated 3‐month‐old and growth factor‐treated 20‐month‐old mice. These results demonstrate that the aged brain retains the capacity to respond to exogenous growth factors with increased neurogenesis, which may have implications for the therapeutic potential of neurogenesis enhancement in age‐associated neurological disorders.
Evolution of male longevity bias in nematodes
Authors: McCulloch Diana , Gems David
Published: May 2003

Many animal species exhibit sex differences in aging. In the nematode Caenorhabditis elegans, under conditions that minimize mortality, males are the longer‐lived sex. In a survey of 12 independent C. elegans isolates, we find that this is a species‐typical character. To test the hypothesis that the C. elegans male longevity bias evolved as a consequence of androdioecy (having males and hermaphrodites), we compared sex‐specific survival in four androdioecious and four dioecious (males and females) nematode species. Contrary to expectation, in all but C. briggsae (androdioecious), males were the longer‐lived sex, and this difference was greatest among dioecious species. Moreover, male lifespan was reduced in androdioecious species relative to dioecious species. The evolutionary theory of aging predicts the evolution of a shorter lifespan in the sex with the greater rate of extrinsic mortality. We demonstrate that in each of eight species early adult mortality is elevated in females/hermaphrodites in the absence of food as the consequence of internal hatching of larvae (matricide). This age‐independent mortality risk can favour the evolution of rapid aging in females and hermaphrodites relative to males.
Involvement of the INK4a/Arf gene locus in senescence
Authors: Collins Carol J. , Sedivy John M.
Published: May 2003

The INK4a/ARF locus encodes two proteins whose expression limits cellular proliferation. Whilst the biochemical activities of the two proteins appear very different, they both converge on regulating the retinoblastoma and p53 tumour suppressor pathways. Neither protein is required for normal development, but lack of either predisposes to the development of malignancy. Both proteins have also been implicated in the establishment of senescence states in response to a variety of stresses, signalling imbalances and telomere shortening. The INK4a/Arf regulatory circuits appear to be partially redundant and show evidence of rapid evolution. Especially intriguing are the large number of biological differences documented between mice and man. We review here the brief history of INK4a/Arf and explore possible links with organismal aging and the evolution of longevity.