bluuebunny/crossref_metadata_2025_split huggingface dataset:
Auditory Responses in Cochlear Implant Users With and Without GJB2 Deafness
Authors: Propst Evan Jon , Papsin Blake C. , Stockley Tracy L. , Harrison Robert V. , Gordon Karen A. 
Published: February 2006

AbstractObjective/Hypothesis: It is reasonable to suppose that the pattern of sensorineural damage along the length of the cochlea depends on the etiology of a hearing loss (HL). In GJB2‐related deafness, we hypothesize that gap junction deficits are uniformly distributed and will result in similar damage along the length of the cochlea as compared with non‐GJB2 subjects. We assessed this by measuring patterns of neural activity and hearing from apical versus basal cochlear implant electrode regions.Study Design: This was a prospective, blind, controlled study.Methods: Blood from 301 pediatric cochlear implant users was analyzed for mutations in GJB2 by direct sequencing. After exclusion of patients with monoallelic GJB2 mutations, associated syndromes, or risk factors for HL that were not congenital, 39 children with biallelic GJB2 mutations and 58 without GJB2 mutations were evaluated. Hearing was measured before implantation at frequencies ranging from 250 Hz to 8 kHz. After implantation, neural activity at the apical and basal ends of the implanted array was measured using electrically evoked compound action potentials of the auditory nerve (ECAPs) and evoked stapedius reflexes (ESRs).Results: GJB2 and non‐GJB2 groups were not significantly different with respect to sex, age at implantation, duration of auditory deprivation, hearing aid use, duration of aided hearing, ear implanted, implant model, or depth of insertion (P > .05). Children with GJB2‐related HL had greater similarities between low‐ and high‐frequency residual hearing and between neural activity electrically evoked at apical and basal regions of the cochlea as compared with children with non‐GJB2‐related HL who demonstrated larger deficits in basal regions.Conclusion: Results suggest more consistent spiral ganglion survival along the length of the cochlea in GJB2‐related HL as compared with non‐GJB2‐related HL, which appears to involve a decreasing gradient of spiral ganglion survival from the apex to the base of the cochlea. Our findings support our premise that in GJB2‐related HL, dysfunction of gap junctions likely occurs to a similar degree in the apical and basal regions of the cochlea. This knowledge might be used to customize implantable devices for patients with HL in the future.
Scanning Electron Microscopic Study of the Nasolabial Cyst: Its Clinical and Embryological Implications
Authors: Su Chih‐Ying , Huang Hung‐Tu , Liu Ho‐Yih , Huang Chao‐Cheng , Chien Chih‐Yen 
Published: February 2006

AbstractObjective: Nasolabial cyst is an uncommon midfacial cyst. It is considered to be a developmental anomaly arising from the rest of nasal respiratory epithelium. Although the cyst is a well‐recognized entity, there remains some confusion of its origin, cell types, and ultrastructures. Based on the routine light microscopic study, some authors reported the epithelial cells of the inner lining of the nasolabial cyst were ciliated; some others reported they were nonciliated. To clarify this, a scanning electron microscopic study is needed.Study Design: This was a prospective clinical series.Methods: A transnasal marsupialization method was used to treat 10 patients with nasolabial cyst. With patients under local anesthesia, the roof of the cyst wall and a disk of nearby nasal mucosa were excised together with a sickle knife and scissors. Surgical specimens were dissected and processed for scanning electron microscopy and histochemistry. Patients were followed up for 8 to 65 months.Results: Marsupialization of cysts was successfully performed on all patients. Electron microscopically, the inner surface of the nasolabial cysts in all the cases was lined with nonciliated columnar epithelium consisting chiefly of goblet cells and basal cells. It is suggested that goblet cells contributed to clear, thin, and yellow mucus present in the cyst lumen. Instead of cilia, these epithelial cell surfaces were equipped with numerous short, globular, or irregular microvilli. Apical cytoplasm of adjacent cells did not tightly adhere to each other. Instead, microsulci of 1 to 3 μm in width formed between cells. Cytoplasmic processes from the lateral border spanned the microsulcus and contacted with those from neighboring cells.Conclusion: The novel study has proved that the lining epithelium on the inner surface of the nasolabial cyst is columnar epithelium that chiefly consisted of two types of cells: goblet cells and basal cells. Not present were ciliated cells that were essential in the other portion of the respiratory tract. Numerous microvilli, instead of cilia, covered the inner lining of the nasolabial cyst, probably as a result of lacking the stimulation of air in ventilation as that on the other portion of the respiratory tract. The cilia of the epithelium were ill developed.
Prediction of Auditory Brainstem Reflex Screening Referrals in High‐Risk Infants
Authors: Lieu Judith E. Cho , Champion Gretchen 
Published: February 2006

AbstractObjectives/Hypothesis: The objectives of this study were to 1) quantify the relative importance of established risk factors for congenital hearing loss (HL), 2) identify other risk factors for congenital HL, and 3) create a prognostic system that can predict the chance of an infant having HL.Methods: The authors conducted a retrospective cohort study with validation of a prognostic system. The authors used a medical record review on 1,863 infants admitted to level II and level III nurseries who underwent auditory brainstem reflex (ABR) hearing screening from 1998 to 1999 (derivation cohort). The primary outcome was hearing screening referral (i.e., hearing screening failure) classified as mild to moderate, moderate to severe, and severe to profound loss. To validate the prognostic system, a medical record review of a separate cohort of 437 infants admitted to a level III nursery who underwent ABR hearing screening in 2002 (validation cohort) was performed.Results: In the derivation cohort, 1,513 infants (81%) passed the ABR screen at 30 dB, 77 (4%) had a unilateral referral, 243 (13%) had a bilateral referral, and 30 (1.6%) did not have a complete screening. In multivariable analysis, the following risk factors were clinically and statistically significant: craniofacial abnormalities, cytomegalovirus infection, bronchopulmonary dysplasia (BPD), maternal ethanol use, syndromes, hydrocephalus, and hyperbilirubinemia.Conclusions: Our results reaffirm the importance of several established risk factors for congenital HL, but suggest that BPD is an important predictor in high‐risk populations. Whether these risk factors are causal or merely associated in congenital HL remains to be determined.
Ambiguous Figures and the Content of Experience
Authors: Macpherson Fiona 
Published: February 2006

AbstractRepresentationalism is the position that the phenomenal character of an experience is either identical with, or supervenes on, the content of that experience. Many representationalists hold that the relevant content of experience is nonconceptual. I propose a counter‐example to this form of representationalism that arises from the phenomenon of Gestalt switching, which occurs when viewing ambiguous figures. First, I argue that one does not need to appeal to the conceptual content of experience or to judgements to account for Gestalt switching. I then argue that experiences of certain ambiguous figures are problematic because they have different phenomenal characters but that no difference in the nonconceptual content of these experiences can be identified. I consider three solutions to this problem that have been proposed by both philosophers and psychologists and conclude that none can account for all the ambiguous figures that pose the problem. I conclude that the onus is on representationalists to specify the relevant difference in content or to abandon their position.
Co‐inheritance of α+‐thalassaemia and sickle trait results in specific effects on haematological parameters
Authors: Wambua Sammy , Mwacharo Jedidah , Uyoga Sophie , Macharia Alexander , Williams Thomas N. 
Published: February 2006

AbstractBoth the sickle cell trait (HbAS) and α+‐thalassaemia are common in many tropical areas. While their individual haematological effects are well described, few studies describe their effects when inherited together. We present data from the Kenyan coast, which suggest that HbAS and α+‐thalassaemia may interact to produce specific effects on haematological parameters. Overall, the difference in Hb concentrations between non‐thalassaemics (αα/αα) and α+‐thalassaemia homozygotes (−α/−α) was greater in non‐HbAS (HbAA) (0·63 g/dl) than in HbAS children (0·25 g/dl). HbAS also ameliorated both the reduced mean cell volume and mean cell haemoglobin normally associated with the −α/−α genotype. Potential mechanisms and implications are discussed.
DNA bending in the Sin recombination synapse: functional replacement of HU by IHF
Authors: Rowland Sally‐J. , Boocock Martin R. , Stark W. Marshall 
Published: February 2006

SummaryThe serine recombinase Sin requires a non‐specific DNA‐bending protein such as Hbsu for activity at its recombination siteresH. Hbsu, and Sin subunits bound at site II ofresH, together regulate recombination, ensuring selectivity for directly repeatedresHsites by specifying assembly of an intertwined synapse. To investigate the role of the DNA‐bending protein in defining the architecture of the synapse, we constructed a chimaeric recombination site (resF) which allows Hbsu to be substituted by IHF, binding specifically between site I (the crossover site) and site II. Two Sin dimers and one IHF dimer can bind together to the closely adjoining sites inresF, forming folded complexes. The precise position of the IHF site within the site I–site II spacer determines the conformation of these complexes, and also the reactivity of theresFsites in recombination assays. The data suggest that a sharp bend with a specific geometry is required in the spacer DNA, to bring the Sin dimers at sites I and II together in the correct relative orientation for synapse assembly and regulation, consistent with our model for a highly condensed synapse in which Hbsu/IHF has a purely architectural function.
Sigma factor selectivity in Borrelia burgdorferi: RpoS recognition of the ospE/ospF/elp promoters is dependent on the sequence of the −10 region
Authors: Eggers Christian H. , Caimano Melissa J. , Radolf Justin D. 
Published: February 2006

SummaryMembers of the ospE/ospF/elp lipoprotein gene families of Borrelia burgdorferi, the Lyme disease agent, are transcriptionally upregulated in response to the influx of blood into the midgut of an infected tick. We recently have demonstrated that despite the high degree of similarity between the promoters of the ospF (PospF) and ospE (PospE) genes of B. burgdorferi strain 297, the differential expression of ospF is RpoS‐dependent, while ospE is controlled by σ70. Herein we used wild‐type and RpoS‐deficient strains of B. burgdorferi and Escherichia coli to analyse transcriptional reporters consisting of a green fluorescent protein (gfp) gene fused to PospF, PospE, or two hybrid promoters in which the −10 regions of PospF and PospE were switched [PospF (E − 10) and PospE (F − 10) respectively]. We found that the PospF−10 region is both necessary and sufficient for RpoS‐dependent recognition in B. burgdorferi, while σ70 specificity for PospE is dependent on elements outside of the −10 region. In E. coli, sigma factor selectivity for these promoters was much more permissive, with expression of each being primarily due to σ70. Alignment of the sequences upstream of each of the ospE/ospF/elp genes from B. burgdorferi strains 297 and B31 revealed that two B31 ospF paralogues [erpK (BBM38) and erpL (BBO39)] have −10 regions virtually identical to that of PospF. Correspondingly, expression of gfp reporters based on the erpK and erpL promoters was RpoS‐dependent. Thus, the sequence of the PospF−10 region appears to serve as a motif for RpoS recognition, the first described for any B. burgdorferi promoter. Taken together, our data support the notion that B. burgdorferi utilizes sequence differences at the −10 region as one mechanism for maintaining the transcriptional integrity of RpoS‐dependent and ‐independent genes activated at the onset of tick feeding.
Involvement of the Escherichia coli folate‐binding protein YgfZ in RNA modification and regulation of chromosomal replication initiation
Authors: Ote Tomotake , Hashimoto Masayuki , Ikeuchi Yoshiho , Su’etsugu Masayuki , Suzuki Tsutomu , Katayama Tsutomu , Kato Jun‐Ichi 
Published: February 2006

SummaryThe Escherichia coli hda gene codes for a DnaA‐related protein that is essential for the regulatory inactivation of DnaA (RIDA), a system that controls the initiation of chromosomal replication. We have identified the ygfZ gene, which encodes a folate‐binding protein, as a suppressor of hda mutations. The ygfZ null mutation suppresses an hda null mutation. The over‐initiation and abortive elongation phenotypes conferred by the hda mutations are partially suppressed in an hda ygfZ background. The accumulation of the active form of DnaA, ATP‐DnaA, in the hda mutant is suppressed by the disruption of the ygfZ gene, indicating that YgfZ is involved in regulating the level of ATP‐DnaA. Although ygfZ is not an essential gene, the ygfZ disruptant grows slowly, especially at low temperature, demonstrating that this gene is important for cellular proliferation. We have identified mnmE (trmE) as a suppressor of the ygfZ disruption. This gene encodes a GTPase involved in tRNA modification. Examination of RNA modification in the ygfZ mutant reveals reduced levels of 2‐methylthio N 6‐isopentenyladenosine, indicating that YgfZ participates in the methylthio‐group formation of this modified nucleoside in some tRNAs. These results suggest that YgfZ is a key factor in regulatory networks that act via tRNA modification.
The intrinsic ATPase activity of Mycobacterium tuberculosis DnaA promotes rapid oligomerization of DnaA on oriC
Authors: Madiraju Murty V. V. S. , Moomey Meredith , Neuenschwander Pierre F. , Muniruzzaman Syed , Yamamoto Kohji , Grimwade Julia E. , Rajagopalan Malini 
Published: February 2006

SummaryOligomerization of the initiator protein, DnaA, on the origin of replication (oriC) is crucial for initiation of DNA replication. Studies in Escherichia coli (Gram‐negative) have revealed that binding of DnaA to ATP, but not hydrolysis of ATP, is sufficient to promote DnaA binding, oligomerization and DNA strand separation. To begin understanding the initial events involved in the initiation of DNA replication in Mycobacterium tuberculosis (Gram‐positive), we investigated interactions of M. tuberculosis DnaA (DnaATB) with oriC using surface plasmon resonance in the presence of ATP and ADP. We provide evidence that, in contrast to what is observed in E. coli, ATPase activity of DnaATB promoted rapid oligomerization on oriC. In support, we found that a recombinant mutant DnaATB proficient in binding to ATP, but deficient in ATPase activity, did not oligomerize as rapidly. The corresponding mutation in the dnaA gene of M. tuberculosis resulted in non‐viability, presumably due to a defect in oriC–DnaA interactions. Dimethy sulphate (DMS) footprinting experiments revealed that DnaATB bound to DnaA boxes similarly with ATP or ADP. DnaATB binding to individual DnaA boxes revealed that rapid oligomerization on oriC is triggered only after the initial interaction of DnaA with individual DnaA boxes. We propose that ATPase activity enables the DnaA protomers on oriC to rapidly form oligomeric complexes competent for replication initiation.
Severe Combined Immunodeficiency in a Fell Pony Foal
Authors: JelÌnek F. , Faldyna M. , Jasurkova‐Mikutova G. 
Published: February 2006

SummaryFive days after birth of a viable Fell pony filly, yellow watery diarrhoea appeared without any signs of systemic disease. Four days later the diarrhoea ceased. On 11th day, the animal showed apathy, and a few days later, the foal was very lethargic, suffered from muscular weakness and severe watery diarrhoea that reappeared. The illness did not respond to therapy. At the age of 21 days the filly spontaneously died under symptoms of intestinal colic and pneumonia. Haematological examinations revealed lower numbers of erythrocytes as well as non‐selective lymphopenia. Phagocytic activity was slightly increased, lymphocyte activity was inhibited. Histopathology showed severe alteration of the lymphatic organs. T and B lymphocytes and antigen‐presenting macrophages were not arranged in characteristic areas, and the quantity of these cells was lower than would be expected. Histopathological changes in lymphatic organs resembled those described in the literature as severe combined immunodeficiency.
Effect of Anticholinergics (Atropine, Glycopyrrolate) and Prokinetics (Metoclopramide, Cisapride) on Gastric Motility in Beagles and Labrador Retrievers
Authors: Burger D. M. , Wiestner T. , Hubler M. , Binder H. , Keiser M. , Arnold S. 
Published: February 2006

SummaryThe effect of atropine, glycopyrrolate, metoclopramide and cisapride on the antral motility was investigated in eight dogs (four Beagles and four Labradors) using passive telemetry. Both anticholinergics induced a pronounced and lasting reduction of the intensity and frequency of the contractions. A definite dose‐related inhibition of the antral motility was seen in Beagles, similar for both active substances. Low doses of atropine (0.02 mg/kg BW i.m.) and glycopyrrolate (0.005 mg/kg BW i.m.) completely inhibited the gastric motility for at least 30 min, whereas higher doses (0.04 or 0.01 mg/kg BW) caused a cessation of activity for more than 3 h. In Labradors, the effects of both active substances were not so dose related and the effect of glycopyrrolate lasted at least 6 h, whereas the effect of atropine gradually decreased after 3 h. A distinct breed difference regarding the effect of the two prokinetics on the antral motility was also observed. In Beagles, the prokinetics, at a low dose (metoclopramide 0.3 mg/kg BW, cisapride 0.2 mg/kg BW), resulted in a significant increase in the amplitude integral. Higher doses (metoclopramide 0.6 mg/kg BW, cisapride 0.5 mg/kg BW) also increased the integrals of the pressure profiles, but significantly less than with the lower doses. In Labradors, both medications, mainly at higher doses, resulted in an increase of the contraction amplitudes. The low dose had no (cisapride) or only a transient effect (metoclopramide). The frequency of the antral contractions was not at all influenced by cisapride, and only in Beagles metoclopramide resulted in a dose‐related increase. It is not clear if the different results in Labradors and Beagles are because of breed or body weight.
Immunohistochemical Expression of Mdm2 and p53 in Canine Cutaneous Mast Cell Tumours
Authors: Wu H. , Hayashi T. , Inoue M. 
Published: February 2006

SummaryThe objective of this study was to evaluate by immunohistochemical means nuclear reactivity for Mdm2 and p53 proteins in 71 canine cutaneous mast cell tumours. Detectable reactivity for Mdm2 was observed in 17 of 23 grade I tumours, 19 of 27 grade II tumours, and 14 of 21 grade III tumours, the grading method used was that byPatnaik et al. [Vet. Pathol., vol. 21, 1984, p. 469]. Increased reactivity for Mdm2 was detected in grade III tumours compared with grade I tumours. In contrast to Mdm2, detectable reactivity for p53 was observed in 17 tumours. Of 39 cases with moderate or marked Mdm2, 34 showed mild or no detectable p53, although only five showed moderate or marked p53. The results suggest that Mdm2 overexpression plays a crucial role in canine mast cell tumorigenesis and is consistent with the histologic grade, and its expression may be induced without p53 overexpression.
Chronic Progressive Autonomic Dysfunction in a Dog
Authors: Adamama‐Moraitou K. K. , Brellou G. D. , Rallis T. S. , Zavros N. , Pardali D. , Dinopoulos A. , Vlemmas I. 
Published: February 2006

SummaryA 3.5‐year‐old intact male American Pit Bull was presented because of urinary incontinence and dysuria. Constipation, followed by diarrhoea, ocular disturbances and finally regurgitation developed over the next 4 years. Autonomic dysfunction was evidenced by clinical presentation, as well as positive ophthalmic pilocarpine test and subnormal Schirmer tear test. Diagnosis, however, was established through histopathological and immunohistochemical examination. Lesions attributable to inflammatory degenerative neuropathy of the autonomic ganglia, which represents one of the various types of human autonomic failure, were detected.
A Case of Suspected Lysosomal Storage Disease in a Neonatal Japanese Black Calf
Authors: Mikami O. , Anjiki T. , Yamato O. , Nakajima Y. 
Published: February 2006

SummaryA 5‐day‐old Japanese black calf was necropsied and intracytoplasmic vacuolations were histologically observed in many tissues. In the central nervous system, intracytoplasmic inclusions and vacuoles were found in neuronal cells. Intracytoplasmic inclusions were more conspicuous in the nuclei containing large nerve cells, especially in the brain stem and spinal cord. These inclusions were stained weak positive to positive with alcian blue, Giemsa, Luxol fast blue and periodic acid–Schiff stains but not with oil red O. Ultrastructurally, neuronal inclusions were observed in lysosomes and consisted of an amorphous electron‐dense substance and occasional membranous structures. These findings seem to differ from the cases of bovine lysosomal diseases that have been reported, and this case may be another type of lysosomal storage disease.
Clinical Pharmacokinetics of Anti‐angiogenic Photodynamic Therapy with Benzoporphyrin Derivative Monoacid Ring‐A in Dogs Having Naturally Occurring Neoplasms
Authors: Osaki T. , Hoshino S. , Hoshino Y. , Takagi S. , Okumura M. , Kadosawa T. , Fujinaga T. 
Published: February 2006

SummaryThe aim of this study was to examine the pharmacokinetics of clinically applied benzoporphyrin derivative monoacid ring‐A (BPD‐MA; Verteporfin®), a second‐generation photosensitizer, during a trial of photodynamic therapy (PDT) in nine dogs having naturally occurring neoplasms. After injecting BPD‐MA at 0.5 mg/kg intravenously, its mean half‐life (t1/2) was found to be 8.14 ± 5.34 h, mean clearance (Cl) 35.13 ± 9.62 ml/(h kg), the mean value of the volume of distribution (Vc) 0.08 ± 0.01 l/kg and the mean steady state volume of distribution (Vss) 0.38 ± 0.31 l/kg respectively. With the exception of a transitional increase in serum alkaline phosphatase activity, no other clinical abnormalities were observed. The t1/2 in dogs with naturally occurring tumours was longer than that in humans, but similar to that in rats. The values of Cl and Vss in dogs having naturally occurring neoplasms were lower than those in humans. It is suggested that the pharmacokinetics of BPD‐MA in tumour‐bearing dogs would be helpful in determining the protocol of a short drug‐light interval PDT with BPD‐MA that mainly targets the tumour vasculature.