bluuebunny/crossref_metadata_2025_split huggingface dataset:
Pulmonary pneumaticity in the postcranial skeleton of extant Aves: A case study examining Anseriformes
Authors: O'Connor Patrick M. 
Published: June 2004

AbstractAnseriform birds were surveyed to examine how the degree of postcranial pneumaticity varies in a behaviorally and size‐diverse clade of living birds. This study attempts to extricate the relative effects of phylogeny, body size, and behavioral specializations (e.g., diving, soaring) that have been postulated to influence the extent of postcranial skeletal pneumaticity. One hundred anseriform species were examined as the focal study group. Methods included latex injection of the pulmonary apparatus followed by gross dissection or direct examination of osteological specimens. The Pneumaticity Index (PI) is introduced as a means of quantifying and comparing postcranial pneumaticity in a number of species simultaneously. Phylogenetically independent contrasts (PICs) were used to examine the relationship between body size and the degree of postcranial pneumaticity throughout the clade. There is a high degree of similarity (i.e., clade‐specificity) within most anseriform subgroups. As a whole, Anseriformes demonstrate no significant relationship between relative pneumaticity and body size, as indicated by regression analysis of body mass on PI. It is apparent, however, that many clades of diving ducks do exhibit lower PIs than their nondiving relatives. By exclusion of diving taxa from analyses, a significant positive slope is observed and the hypothesis of relatively higher pneumaticity in larger‐bodied birds is only weakly supported. However, low correlations indicate that factors other than body size account for much of the variation observed in relative pneumaticity. Pneumaticity profiles were mapped onto existing phylogenetic hypotheses. A reduction in the degree of postcranial pneumaticity occurred independently in at least three anseriform subclades specialized for diving. Finally, enigmatic pneumatic features located in distal forelimb elements of screamers (Anhimidae) result from invasion of bone by a network of subcutaneous air sac diverticula spreading distally along the wings. J. Morphol. 261:141–161, 2004. © 2004 Wiley‐Liss, Inc.
Functional morphology of the middle ear in Chlorotalpa golden moles (mammalia, Chrysochloridae): Predictions from three models
Authors: Mason Matthew J. 
Published: June 2004

AbstractThe ossicular apparatus of golden moles in the genus Chlorotalpa has received comparatively little attention in the literature, although the malleus is known to be intermediate in size between the “unmodified” malleus of Amblysomus and the hypertrophied mallei found in some other golden moles. In the present study, the middle ear structures of three Chlorotalpa species (C. duthieae, C. sclateri, and C. arendsi) are described. Measurements of middle ear structures were applied into three existing models of middle ear function. The predictions from the models suggest that the airborne hearing of Chlorotalpa species is limited to relatively low frequencies, but the impedance transformation by the middle ear apparatus is expected to be reasonably efficient. The sensitivity of the middle ear apparatus to inertial bone conduction is intermediate between that predicted for Amblysomus and that predicted for species with hypertrophied mallei. Hearing in fossorial mammals may be limited by factors other than the middle ear apparatus: the predictions for Chlorotalpa must therefore be treated with caution. However, a consideration of the “intermediate” middle ear morphology of Chlorotalpa species sheds some light on the origin of ossicular hypertrophy in golden moles. The limited enlargement of the malleus seen in Chlorotalpa is expected to have improved seismic sensitivity by bone conduction significantly at low frequencies, while airborne hearing might not have been adversely affected. J. Morphol. 261:162–174, 2004. © 2004 Wiley‐Liss, Inc.
Larynx morphology and sound production in three species of Testudinidae
Authors: Sacchi Roberto , Galeotti Paolo , Fasola Mauro , Gerzeli Giuseppe 
Published: June 2004

AbstractAlthough the ability to vocalize is widespread among tortoises, the mechanisms of sound production in chelonians remain undescribed. In this study, we analyze the morphology and histology of the larynx of three species of Testudinidae (Testudo hermanni, T. graeca, and T. marginata) in order to ascertain the presence of vibrating acoustic structure, and based on our findings we propose a general model for phonation in tortoises. The structure of the larynx of the three tortoises analyzed is simple: three cartilages (the cricoid and two arytenoids) form the skeleton of the larynx, while two pairs of muscles (the dilators and constrictors) control the widening and closing of the glottis. The larynx is supported in the oral cavity by the hyoid cartilage, which in tortoises assumes the same functions of the thyroid cartilage of mammals. Two bands of elastic fibers are inserted in the lateral walls of the larynx just upstream of the glottis, and can be stretched away from the hyoid by the movements of the arytenoids. Their position and structure suggest that these bands are capable of vibrating during exhalation, and therefore may be considered vocal cords. The cricoid of T. marginata and T. graeca hold two diverticula, not previously reported, which might function as a low‐frequency resonating chamber, improving the harmonic structure of tortoise calls. The structure of the larynx is compared with that of other vertebrates and the relationships between morphology and phonation are discussed. This is the first detailed description of anatomical structures possibly devoted to vocalization in chelonians. J. Morphol. 261:175–183, 2004. © 2004 Wiley‐Liss, Inc.
Glycoconjugate localization in larval and adult skin of the bullfrog, Rana catesbeiana: A lectin histochemical study
Authors: Kaltenbach Jane C. , Faszewski Ellen E. , Nytch Karen E. , Potter Christine H. , Shanthakumar Narmatha , Fakin Alina 
Published: June 2004

AbstractThis study investigates whether or not the distribution of specific glycoconjugates within the skin is related to the regulation of water balance in the aquatic larvae and semiaquatic adults of the bullfrog, Rana catesbeiana. A lectin histochemical study was carried out on paraffin sections of dorsal and ventral skin from tadpoles in representative stages as well as from adult frogs. Sections were stained with the following horseradish peroxidase (HRP)‐conjugated lectins, which bind to specific terminal sugar residues of glycoconjugates: UEA 1 for α‐L‐fucose, SBA for N‐acetyl‐D‐galactosamine, WGA for N‐acetyl‐B‐D‐glucosamine, and PNA for β‐galactose. Results indicate that lectins serve as markers for specific skin components (e.g., a second ground substance layer within the dermis was revealed by positive UEA 1 staining). Moreover, each lectin has a specific binding pattern that is similar in dorsal and ventral skin; the larval patterns change as the skin undergoes extensive histological and physiological remodeling during metamorphic climax. These findings enhance our understanding of glycoconjugates and their relationship to skin structure and function—in particular, to the regulation of water balance in R. catesbeiana. J. Morphol. 261:184–195, 2004. © 2004 Wiley‐Liss, Inc.
Spermatozoa of Pseudinae (Amphibia, Anura, Hylidae), with a test of the hypothesis that sperm ultrastructure correlates with reproductive modes in anurans
Authors: Garda Adrian A. , Costa Gabriel C. , Colli Guarino R. , Báo Sônia N. 
Published: June 2004

AbstractWe describe, for the first time, the sperm ultrastructure of the two genera of Pseudinae. Based on sperm ultrastructure, the five species herein examined can be separated into three groups: one containing Pseudis paradoxa, P. bolbodactyla, and P. tocantins, the second containing P. minuta, and the third containing Lysapsus laevis. The midpiece is similar in all species and auxiliary fibers and the undulating membrane are absent. In Pseudis a subacrosomal cone and a multilaminar structure (P. minuta) or a granular material (P. paradoxa group) are seen above the nucleus. Lysapsus laevis has only remnants of the subacrosomal cone. All species have peripheral fibers associated with the outer doublets of the axoneme. We tested the hypothesis of correlation between the presence of an undulating membrane and fertilization environments in anurans using a concentrated changes test (CCT) based on the Hay et al. (Mol Biol Evol 1995;12:928–937) hypothesis of phylogenetic relationships among anuran families. Only a subset of the resolved topologies derived from the Hay et al. (1995) cladogram, where Ranoidea is the sister‐group of Sooglossidae, produced significant probabilities of the CCT. Therefore, support for the correlation between sperm ultrastructure and fertilization environments in anurans is, at best, equivocal. J. Morphol. 261:196–205, 2004. © 2004 Wiley‐Liss, Inc.
Feeding mechanisms in two treefrogs, Hyla nana and Scinax nasicus (Anura: Hylidae)
Authors: Vera Candioti M.F. , Lavilla E.O. , Echeverría D.D. 
Published: June 2004

AbstractAfter the description of the chondrocranium, hyobranchial apparatus, associated musculature, buccal apparatus, buccopharyngeal cavity, digestive tract, and gut contents, it was possible to define the feeding modes of Scinax nasicus and Hyla nana tadpoles (Gosner Stages 31–36). Scinax nasicus larvae are “typical” microphagous tadpoles, with keratodonts and robust rostrodonts appropriate for rasping surfaces and mincing of food particles; the buccopharyngeal cavity is equipped with filtering structures and has a conspicuous glandular zone and a highly developed branchial basket. In contrast, H. nana tadpoles have a modified buccal apparatus; the reduction of the buccopharyngeal and branchial basket structures, together with the high lever–arm ratio and the great development of the depressor muscles of the buccal floor are indicative of macrophagous feeding. J. Morphol. 261:206–224, 2004. © 2004 Wiley‐Liss, Inc.
Myo‐anatomy of juvenile and adult loxosomatid Entoprocta and the use of muscular body plans for phylogenetic inferences
Authors: Wanninger Andreas 
Published: June 2004

AbstractThe anatomy of the muscle bauplan in juvenile buds and adult specimens of the solitary loxosomatid entoprocts Loxosoma nielseni and L. annelidicola was studied by means of fluorescence staining of F‐actin and confocal laser scanning microscopy. Although the general myo‐anatomy of the body wall shows numerous similarities, both species express significant variations in the arrangement of their pedal muscles. In addition, L. annelidicola alone shows a distinct pair of rectum retractor muscles. Circular muscles are absent in the entire body wall of both species, as well as in previously investigated colonial taxa, which is therefore regarded as basal for Entoprocta. This is in striking contrast to the conditions found in other spiralian or lophotrochozoan taxa. The simple morphology of entoproct tentacle muscles, however, coincides with the phoronid‐ectoproct condition and may be due to functional constraints of a simple filter‐feeding system. This work shows that variations in the muscular anatomy provide useful characters for systematic analyses on species as well as phylum level and thus allow significant insight regarding metazoan body plan evolution. The phenomenon of phenotypic plasticity and its consequences for phylogenetic interpretations, however, must be carefully considered. J Morphol. 261:249–257, 2004. © 2004 Wiley‐Liss, Inc.
Similar HIV‐1 evolution and immunological responses at 10 years despite several therapeutic strategies and host HLA Types
Authors: Arnedo‐Valero Mireia , Plana Montserrat , Mas Antonio , Guilà Meritxell , Gil Cristina , Castro Pedro , Garcia Felipe , Domingo Esteban , Gatell Josep Ma , Pumarola Tomàs 
Published: June 2004

AbstractTwo sexual partners infected with related HIV‐1 viruses and enrolled in different therapeutic strategies including structured treatment interruptions (STI) provided us an opportunity to compare long term (10 years) viral genetic evolution for closely related isolates in different hosts. HLA loci were molecularly typed and different genetic markers were studied. The viral genetic evolution was studied by sequencing pol and env genes. The HIV‐specific CD4+ and CD8+ T cell responses were assessed by the lymphoproliferative response (LPR) and an ELISPOT assay, respectively. HLA class I loci of patients A and B were different and both of them were heterozygous for CCR5Δ32 gene. During the two STI studies, viral load of both patients rebounded after treatment interruption and both developed a transitory strong helper and CTL responses. After definitive interruption of therapy, viral load remained belowx 5,000 copies/ml without therapy during the two years of follow‐up. Two patients infected with related viruses showed a similar dynamics of viral evolution and CD4 T cells, despite hosts having a different HLA type and being treated with several therapeutic protocols, after 10 years of infection. These results suggest that, in this case, an effective immunological response to STI depended more on the virus than on the characteristics of the host. J. Med. Virol. 73:495–501, 2004. © 2004 Wiley‐Liss, Inc.
Precision and stability of hepatitis B virus DNA levels in chronic surface antigen carriers
Authors: Plentz Annelie , Koller Gabriele , Weinberger Klaus M. , Jilg Wolfgang 
Published: June 2004

AbstractQuantitative determination of hepatitis B virus (HBV) DNA concentration is the most important measure for an estimation of the infectivity of an HBV positive health care worker and the basis for the decision whether he or she is allowed to perform exposure prone procedures. Thus questions are raised on how reliable quantitative HBV DNA assays are, and how stable is the HBV DNA concentration is in a healthy chronic HBV carrier. Therefore, in the present study two commercially available quantitative HBV DNA assays, the Amplicor HBV Monitor and the HBV Test Hybrid Capture II, and an “in house” quantitative HBV TaqMan PCR, analysing 101 sera of HBsAg positive patients for HBV DNA were compared. In addition, HBV DNA concentrations were followed in 14 healthy chronic carriers for up to 6 years. Despite a good overall correlation between the three tests considerable differences were found for the results of individual sera. Fifty‐one percent of sera showed differences within one order of magnitude, 45% differed by a factor above 10 and 4% even by a factor of 100 and higher. The follow‐up of the HBV DNA concentrations in 14 carriers showed in 7 carriers a rather stable course with variations within one order of magnitude, whereas in the other half the DNA concentrations fluctuated by factors between 102 and 106 over the observation period. Thus, viral load determinations in health care workers have to be interpreted with some caution, especially when they are the basis of far‐reaching decisions. J. Med. Virol. 73:522–528, 2004. © 2004 Wiley‐Liss, Inc.
Expression of hepatitis C virus core protein inhibits interferon‐induced nuclear import of STATs
Authors: Melén Krister , Fagerlund Riku , Nyqvist Maria , Keskinen Päivi , Julkunen Ilkka 
Published: June 2004

AbstractIFN‐α combined with ribavirin is used for the treatment of chronic hepatitis C. However, HCV has mechanisms to resist the antiviral actions of IFN‐α. In order to study the molecular mechanisms of this resistance, the effect of HCV gene expression on IFN‐induced nuclear import of STAT transcription factors and the expression of antiviral MxA protein were studied. In transiently transfected hepatoma cells, HCV core and NS5A proteins clearly inhibited the nuclear import of STAT1 and MxA protein expression (core only), whereas other viral proteins had only a marginal effect. To confirm these observations, human osteosarcoma‐derived cell lines, which inducibly express HCV core protein, the entire structural region (core‐E1‐E2‐p7), the NS3‐4A complex, NS4B, NS5A, or NS5B proteins were also used. IFN‐induced nuclear accumulation of STAT1 was almost completely and STAT2 was partially blocked in cell lines expressing high levels of HCV core protein. Subsequently, in these cells, IFN‐α‐induced MxB protein expression was decreased. Tumor necrosis factor‐α (TNF‐α)‐induced nuclear import of NF‐κB was only weakly or not at all inhibited, suggesting that the nuclear import machinery in general was not impaired. The results demonstrate a novel mechanism by which HCV gene expression may interfere with IFN‐mediated host defence systems. J. Med. Virol. 73:536–547, 2004. © 2004 Wiley‐Liss, Inc.
Failure to diagnose recent hepatitis C virus infections in London injecting drug users
Authors: Aarons Emma , Grant Paul , Soldan Kate , Luton Pete , Tang Julian , Tedder Richard 
Published: June 2004

AbstractHepatitis C virus (HCV) infection results in chronic liver disease in a substantial proportion of those infected. Most new cases of HCV infection in the UK are associated with intravenous drug use. It is important to identify these infections because of the implications for the future health of the individuals concerned and for the control of further spread of infection. However, as hepatitis C infection is characterised by a relatively long asymptomatic period of seronegative viraemia, a laboratory diagnostic protocol that does not test HCV seronegative samples for the presence of HCV RNA may wrongly designate HCV viraemic seronegative individuals as uninfected. Amongst 424 injecting drug users whose serum was sent to our diagnostic laboratory for “HCV screening” over a 14‐month period, the prevalence of HCV seropositivity was 48.4%. We retrospectively identified seven individuals for whom there was evidence of recent acquisition of HCV infection. Three of these infections were identified using our routine diagnostic protocol: testing for the presence of HCV‐specific antibody and performing HCV RNA testing only on seropositive and seroindeterminate specimens. However, four cases were only identified by HCV RNA testing of HCV seronegative serum. On the basis of these observations, we estimate the incidence of HCV infection amongst London injecting drug users as being 14.3 per 100 person‐years. We advocate that all HCV seronegative blood samples obtained from injecting drug users should be tested for the presence of HCV RNA, and suggest that this could be done efficiently by nucleic acid testing the specimens in small pools. J. Med. Virol. 73:548–553, 2004. © 2004 Wiley‐Liss, Inc.
Prevalence of antibodies to hepatitis E virus among Japanese blood donors: Identification of three blood donors infected with a genotype 3 hepatitis E virus
Authors: Fukuda Satoko , Sunaga Junko , Saito Nobuo , Fujimura Kuniko , Itoh Yaeko , Sasaki Masahide , Tsuda Fumio , Takahashi Masaharu , Nishizawa Tsutomu , Okamoto Hiroaki 
Published: June 2004

AbstractRisk factors for acquiring hepatitis E among individuals in industrialized countries including Japan are not fully understood. We investigated whether Japanese blood donors with or without an elevated alanine aminotransferase (ALT) level are likely to have hepatitis E virus (HEV) infection. Serum samples were collected from 5,343 voluntary blood donors including 1,087 donors with elevated ALT of 61–966 IU/L and 4,256 donors with normal ALT (≤60 IU/L) at two Japanese Red Cross Blood Centers, and were tested for the presence of anti‐HEV IgG by in‐house enzyme‐linked immunosorbent assay (ELISA). Overall, 200 donors (3.7%) were positive for anti‐HEV IgG, including 32 (2.9%) with elevated ALT and 168 (3.9%) with normal ALT. Serum samples with anti‐HEV IgG were further tested for the presence of anti‐HEV IgM by in‐house ELISA and for HEV RNA by reverse transcription (RT)‐polymerase chain reaction (PCR). Three donors with ALT of 966, 62 or 61 IU/L were positive for anti‐HEV IgM and HEV RNA. The HEV isolates obtained from the three viremic donors segregated into genotype 3, were 91.5–93.4% similar to each other in the 412 nucleotide sequence of open reading frame 2, and had the highest identity of 91.5–94.9% with the JRA1 isolate which was recovered from a Japanese patient with sporadic acute hepatitis E who had never been abroad, suggesting that these three HEV isolates are indigenous to Japan. This study suggests that a small but significant proportion of blood donors in Japan with or without elevated ALT are viremic and are potentially able to cause transfusion‐associated hepatitis E. J. Med. Virol. 73:554–561, 2004. © 2004 Wiley‐Liss, Inc.
Detection of ganciclovir resistance after valacyclovir‐prophylaxis in renal transplant recipients with active cytomegalovirus infection
Authors: Alain S. , Hantz S. , Scieux C. , Karras A. , Mazeron M.C. , Szelag J.C. , Imbert B.M. , Fillet A.M. , Gouarin S. , Mengelle C. , de Wilde A. , Cogne N. , Champier G. , Rogez S. , Legendre C. , Denis F. 
Published: June 2004

AbstractWhether valaciclovir (VCV) prophylaxis could be responsible for ganciclovir (GCV)‐resistance of Human cytomegalovirus (HCMV) in transplantation has never been documented. A multicentric retrospective pilot study was undertaken to detect GCV‐resistance through mutations within the UL97 gene in renal transplant recipients who experienced active HCMV infection and received valacyclovir prophylaxis. Twenty‐three patients who experienced HCMV antigenaemia or DNAemia during or at the end of prophylaxis were included. UL97 genotyping was carried out on peripheral blood samples, using a nested in‐house PCR, which amplified the full‐length UL97 gene. One patient has a resistance‐related mutation (M460I); the major risk factor for emergence of resistance in this patient was the presence of early and persistent antigenaemia. GCV‐resistance during VCV‐prophylaxis was rare after renal transplantation. However, special attention must be paid to patients developing early active HCMV infection under prophylaxis. J. Med. Virol. 73:566–573, 2004. © 2004 Wiley‐Liss, Inc.
Immune responses to Epstein–Barr virus lytic proteins in patients with nasopharyngeal carcinoma
Authors: Liu Mei‐Ying , Huang Yu‐Tzu , Sheen Tzung‐Shiahn , Chen Jen‐Yang , Tsai Ching‐Hwa 
Published: June 2004

AbstractImmune responses to three Epstein–Barr virus (EBV) lytic proteins, DNase, thymidine kinase (TK), and BMRF‐1 gene products (50/52 kDa diffused early antigen, EA‐D complex) were determined in EBV‐infected control individuals and patients with nasopharyngeal carcinoma (NPC). Immunofluorescence assays (IFA) were used to detect their humoral immune responses using recombinant EBV lytic proteins expressed in a baculovirus system as antigens. Cell proliferation assays were performed to evaluate their cellular immune responses by monitoring 3H‐thymidine incorporation. Seventy patients with NPC and 32 non‐cancer controls were analyzed. The results of IFA showed antibody titers to all three EBV lytic proteins to be higher in the patients with NPC especially for the IgA class. Positivity rates of the three IgA antibodies also were higher in the patients with NPC population. Furthermore, the profiles of the IgA antibodies correlated with those to total early antigens (EA) expressed in the early phase and viral capsid antigen (VCA) expressed in the late phase, of EBV replication. The most interesting finding was that antibody titers to the three EBV lytic proteins were associated significantly with metastases of cervical lymph nodes in patients with NPC. As for cellular immunity to the EA‐D complex and DNase, weak responses were observed in the cell proliferation assays. Peripheral blood cells from most individuals could not be stimulated to proliferate, except for a few patients with NPC whose antibody titers against the EA‐D complex and DNase also were very high. J. Med. Virol. 73:574–582, 2004. © 2004 Wiley‐Liss, Inc.