bluuebunny/crossref_metadata_2025 huggingface dataset:
The lamina-associated polypeptide 2 (LAP2) isoforms β, γ andω of zebrafish: developmental expression and behavior during the cell cycle
Authors: Schoft Vera K. , Beauvais Ariane J. , Lang Carmen , Gajewski Andreas , Prüfert Kristina , Winkler Christoph , Akimenko Marie-Andrée , Paulin-Levasseur Micheline , Krohne Georg
Published: May 2003

Zebrafish lamina-associated polypeptides 2 (ZLAP2) β, γ andω have in common an N-terminal region with a LEM domain, and in the C-terminal half of the molecule a lamina binding domain and a membrane spanning sequence. The maternally synthesized ω is the largest isoform and the only LAP2 present in the rapidly dividing embryonic cells up to the gastrula stage. ZLAP2ω levels decrease during development, concomitant with the increase of the somatic isoforms ZLAP2β and γ. In somatic zebrafish cells ZLAP2γ is the predominant isoform, whereas only small amounts of ZLAP2β are present.

During early embryonic development, ZLAP2ω becomes associated with mitotic chromosomes before anaphase. The surface of these chromosomes is decorated with vesicles, and each chromosome assembles its own nuclear envelope at the end of mitosis (karyomere formation). Ectopically expressed ZLAP2ω-green fluorescent protein (GFP) fusion protein targets vesicles to mitotic chromosomes in Xenopus A6 cells, suggesting that ZLAP2ω is involved in karyomere formation during early zebrafish development.

When ZLAP2β and γ were expressed as GFP fusion proteins in Xenopus A6 cells, the β- but not the γ-isoform was found in association with mitotic chromosomes, and ZLAP2β-containing chromosomes were decorated with vesicles. Further analysis of ZLAP2-GFP fusion proteins containing only distinct domains of the ZLAP2 isoforms revealed that the common N-terminal region in conjunction with β- or ω-specific sequences mediate binding to mitotic chromosomes in vivo.
Frizzled receptor dimerization is sufficient to activate the Wnt/β-catenin pathway
Authors: Carron Clémence , Pascal Aude , Djiane Alexandre , Boucaut Jean-Claude , Shi De-Li , Umbhauer Muriel
Published: May 2003

Wnt signaling has an important role in cell-fate determination, tissue patterning and tumorigenesis. Wnt proteins signal through seven-pass transmembrane receptors of the frizzled family to activateβ-catenin-dependent transcription of target genes. Using early Xenopus embryos, we show that frizzled receptors can dimerize and that dimerization is correlated with activation of the Wnt/β-catenin pathway. Co-immunoprecipitation studies revealed that the receptor Xfz3 exists as a dimer when expressed in Xenopus embryos, and it has been shown to activate the Wnt/β-catenin pathway as revealed by expression of the target gene siamois. Xfz3 dimerization requires intramolecular and/or intermolecular disulfide linkages, and the N-terminal extracellular region of the receptor, including the cysteine-rich domain (CRD), is sufficient for dimerization. The receptor Xfz7 behaves differently from Xfz3 when overexpressed in the embryo as Xfz7 is monomeric and is unable to directly activate the Wnt/β-catenin pathway. However, activation of this pathway can be achieved by artificially forcing Xfz7 dimerization. These results provide the first direct evidence for the dimerization of frizzled receptors and suggest that dimerization contributes to transducing the Wnt/β-catenin signal.
SFRP1 modulates retina cell differentiation through aβ-catenin-independent mechanism
Authors: Esteve Pilar , Trousse Françoise , Rodríguez Josana , Bovolenta Paola
Published: May 2003

Secreted frizzled related proteins (SFRPs) are soluble molecules capable of binding WNTS and preventing the activation of their canonical signalling cascade. Here we show that Sfrp1 contributes to chick retina differentiation with a mechanism that does not involve modifications in the transcriptional activity of β-catenin. Thus, addition of SFRP1 to dissociated retinal cultures or retroviral mediated overexpression of the molecule consistently promoted retinal ganglion and cone photoreceptor cell generation, while decreasing the number of amacrine cells. Measure of the activity of the β-catenin-responsive Tcf-binding site coupled to a luciferase reporter in transiently transfected retinal cells showed that Sfrp1 was unable to modify the basal β-catenin transcriptional activity of the retina cells. Interestingly, a dominant-negative form of GSK3β gave similar results to those of Sfrp1, and a phosphorylation-dependent inhibition of GSK3β activity followed SFRP1 treatment of retina cells. Furthermore, retroviral mediated expression of a dominant-negative form of GSK3β induced a retina phenotype similar to that observed after Sfrp1 overexpression, suggesting a possible involvement of this kinase in SFRP1 function.
An interaction between Sla1p and Sla2p plays a role in regulating actin dynamics and endocytosis in budding yeast
Authors: Gourlay Campbell W. , Dewar Hilary , Warren Derek T. , Costa Rosaria , Satish Nilima , Ayscough Kathryn R.
Published: May 2003

The importance of a dynamic actin cytoskeleton for facilitating endocytosis has been recognised for many years in budding yeast and is increasingly recognised in mammalian cells. However, the mechanism for actin recruitment and the role it plays in endocytosis is unclear. Here we show the importance of two yeast proteins in this process. We demonstrate that Sla1p and Sla2p interact in vitro and in vivo and that this interaction is mediated by the central domain of Sla2p, which includes its coiled-coil region, and by a domain of Sla1p between residues 118 and 361. Overexpression of the interacting fragment of Sla1p causes reduced fluid-phase endocytosis and,interestingly, defects in subsequent trafficking to vacuoles. We show that Sla2p is required for the polarised localisation of Sla1p in cells but not for its cortical localisation or for its overlapping localisation with actin. Generation of an Δsla1Δsla2 double mutant demonstrates that Sla2p is likely to act upstream of Sla1p in endocytosis,whereas sensitivity to latrunculin-A suggests that the proteins have opposite effects on actin dynamics. We propose that Sla2p recruits Sla1p to endocytic sites. Sla1p and its associated protein Pan1p then regulate actin assembly through interactions with Arp2/3 and Arp2/3-activating proteins Abp1p and Las17/Bee1p.
Biochemical characterization, distribution and phylogenetic analysis ofDrosophila melanogasterryanodine and IP3 receptors, and thapsigargin-sensitive Ca2+ ATPase
Authors: Vázquez-Martínez Olivia , Cañedo-Merino Rafael , Díaz-Muñoz Mauricio , Riesgo-Escovar Juan R.
Published: May 2003

We characterized the biochemistry, distribution and phylogeny of Drosophila ryanodine (RyR) and inositol triphosphate(IP3R) receptors and the endoplasmic reticulum Ca2+-ATPase (SERCA) by using binding and enzymatic assays, confocal microscopy and amino acid sequence analysis. [3H]-ryanodine binding in total membranes was enhanced by AMP-PCP, caffeine and xanthine, whereas Mg2+, Ruthenium Red and dantrolene were inhibitors.[3H]-ryanodine binding showed a bell-shaped curve with increasing free [Ca2+], without complete inhibition at millimolar levels of[Ca2+]. [3H]-IP3 binding was inhibited by heparin, 2-APB and xestospongin C. Microsomal Ca2+-ATPase activity was inhibited by thapsigargin. Confocal microscopy demonstrated abundant expression of ryanodine and inositol triphosphate receptors and abundant Ca2+-ATPase in Drosophila embryos and adults. Ryanodine receptor was expressed mainly in the digestive tract and parts of the nervous system. Maximum parsimony and Neighbour Joining were used to generate a phylogenetic classification of Drosophila ryanodine and insitol triphosphate receptors and Ca2+-ATPase based on 48 invertebrate and vertebrate complete sequences. The consensus trees indicated that Drosophila proteins grouped with proteins from other invertebrates,separately from vertebrate counterparts.

Despite evolutionary distances, our functional results demonstrate that Drosophila ryanodine and inositol triphosphate receptors and Ca2+-ATPase are reasonably similar to vertebrate counterparts. Our protein expression data are consistent with the known functions of these proteins in the Drosophila digestive tract and nervous system. Overall, results show Drosophila as a valuable tool for intracellular Ca2+ dynamics studies in eukaryotes.
NF-κB signalling is inhibited by glucocorticoid receptor and STAT6 via distinct mechanisms
Authors: Nelson Glyn , Wilde Geraint J. C. , Spiller David G. , Kennedy Stephnie M. , Ray David W. , Sullivan Elaine , Unitt John F. , White Michael R. H.
Published: May 2003

NF-κB transcription factors are involved in the cellular response to stress, and are regulated by inhibitor (IκB)proteins, which prevent NF-κB-mediated transcription by maintaining NF-κB in the cytoplasm. Proteins from other pathways are also known to regulate NF-κB negatively, notably the glucocorticoid receptor (GR) and IL-4-responsive STAT6. Both pathways were shown to inhibit NF-κB-mediated transcription, by expressing either STAT6 or GR and activating the respective pathways. Using fluorescent fusion proteins, we show that GR alters the timing of activated p65 NF-κB nuclear occupancy by increasing the export rate of p65 and is independent of whether GR is present as a dimer or monomer. Expression of STAT6 was also shown to alter p65 nuclear occupancy but appeared to affect the import rate and hence the overall maximal level of p65 translocation. Activating STAT6 with IL-4 prior to activating NF-κB significantly increased this inhibition. Investigation of IκBa showed that activated STAT6 inhibited TNFα-mediated IκBa phosphorylation and degradation, whereas GR activation did not alter IκBαkinetics. This demonstrates a clear separation of two distinct mechanisms of inhibition by STAT6 and GR upon the NF-κB pathway.
Biogenesis and nuclear export of ribosomal subunits in higher eukaryotes depend on the CRM1 export pathway
Authors: Thomas Franziska , Kutay Ulrike
Published: May 2003

The production of ribosomes constitutes a major biosynthetic task for cells. Eukaryotic small and large ribosomal subunits are assembled in the nucleolus and independently exported to the cytoplasm. Most nuclear export pathways require RanGTP-binding export receptors. We analyzed the role of CRM1, the export receptor for leucine-rich nuclear export signals (NES), in the biogenesis of ribosomal subunits in vertebrate cells. Inhibition of the CRM1 export pathway led to a defect in nuclear export of both 40S and 60S subunits in HeLa cells. Moreover, the export of newly made ribosomal subunits in Xenopus oocytes was efficiently and specifically competed by BSA-NES conjugates. The CRM1 dependence of 60S subunit export suggested a conserved function for NMD3, a factor proposed to be a 60S subunit export adaptor in yeast. Indeed, we observed that nuclear export of human NMD3(hNMD3) is sensitive to leptomycin B (LMB), which inactivates CRM1. It had,however, not yet been demonstrated that Nmd3 can interact with CRM1. Using purified recombinant proteins we have shown here that hNMD3 binds to CRM1 directly, in a RanGTP-dependent manner, by way of a C-terminal NES sequence. Our results suggest that the functions of CRM1 and NMD3 in ribosomal subunit export are conserved from yeast to higher eukaryotes.
Contributions of molecular binding events and cellular compliance to the modulation of leukocyte adhesion
Authors: Wojcikiewicz Ewa P. , Zhang Xiaohui , Chen Aileen , Moy Vincent T.
Published: May 2003

The interaction of leukocyte function-associated antigen-1 (LFA-1) and intercellular adhesion molecule-1 (ICAM-1) is central to the regulation of adhesion in leukocytes. In this report, we investigated the mechanisms by which phorbol myristate acetate (PMA) promotes LFA-1-dependent cell adhesion. The adhesion of PMA-stimulated cells to immobilized ICAM-1 was quantified in direct force measurements acquired by atomic force microscopy (AFM). Enhanced adhesion of PMA-stimulated cells to immobilized ICAM-1 stemmed from an increase in the number of LFA-1–ICAM-1 complexes formed between the two apposing surfaces on contact, rather than by affinity modulation of LFA-1. Single molecule force measurements revealed that the force spectrum of the LFA-1–ICAM-1 complex formed by PMA-stimulated cells is identical to the force spectrum of the complex formed by resting cells. Thus, PMA stimulation does not modify the mechanical strength of the individual LFA-1–ICAM-1 interaction. Instead, the enhanced cell adhesion of PMA-stimulated cells appears to be a complex process that correlates with changes in the mechanical properties of the cell. We estimate that changes in the elasticity of the cell gave rise to a more than 10-fold increase in cell adhesion.
PTHrP [67-86] regulates the expression of stress proteins in breast cancer cells inducing modifications in urokinase-plasminogen activator and MMP-1 expression
Authors: Luparello Claudio , Sirchia Rosalia , Pupello Daniela
Published: May 2003

It was previously reported that a midregion domain of parathyroid hormone-related protein (PTHrP), that is, [67-86]-amide, is able to restrain growth and promote matrigel penetration by the 8701-BC cell line, derived from a biopsy fragment of a primary ductal infiltrating carcinoma of the human breast, and that cell invasion in vitro is drastically impaired by inactivation of urokinase-plasminogen activator (uPa). In this study we started a more detailed investigation of the possible effects on gene expression arising from the interaction between PTHrP [67-86]-amide and 8701-BC breast cancer cells by a combination of conventional-, differential display-and semi-quantitative multiplex-polymerase chain reaction (PCR)assays. We present here the first evidence that the upregulation of some stress-related genes, most noticeably heat shock factor binding protein-1(hsbp1) and heat shock protein 90 (hsp-90), is involved in the acquisition of an in vitro more invasive phenotype by cells treated with midregion PTHrP. This is conceivably accomplished by sequestering and inactivating heat shock factor-1 (hsf1) which is able to recognize Ets transcription-factor-binding sites present in some gene promoters, such as those of uPa and matrix metalloprotease-1 (MMP-1). In fact,our data show that incubation of PTHrP [67-86]-amide-treated cells with either antisense hsbp1-oligonucleotide or geldanamycin, an hsp90-inactivating antibiotic, results in downregulation of uPa and upregulation of MMP-1, and in a prominent inhibition of cell invasion in matrigel-containing Transwell chambers. Alternatively, incubation of untreated 8701-BC cells with quercetin, a flavonoid known to decrease the amount of free hsf1, is found to induce upregulation of uPa and downregulation of MMP-1, and an increase of matrigel invasion by cells, thus providing further supporting data of the involvement of hsf unavailability on the modulation of uPa and MMP-1 expression and on cell invasive behaviour. These studies confirm a previous postulate that over-secretion of uPa, rather than of other extracellular proteases, is a primary condition for the increase of invasive activity triggered by PTHrP [67-86]-amide in vitro,and support a role for midregion forms of PTHrP in potentially affecting pathological mammary growth and differentiation. They also identify two new key protagonists in the complex scenario of breast tumor cell invasiveness in vitro, that is, hsbp1 and hsp90, which deserve further and more extensive studies as potential and attractive molecular targets for anti-breast cancer treatments.
Modeling tissue-specific signaling and organ function in three dimensions
Authors: Schmeichel Karen L. , Bissell Mina J.
Published: May 2003

In order to translate the findings from basic cellular research into clinical applications, cell-based models need to recapitulate both the 3D organization and multicellular complexity of an organ but at the same time accommodate systematic experimental intervention. Here we describe a hierarchy of tractable 3D models that range in complexity from organotypic 3D cultures(both monotypic and multicellular) to animal-based recombinations in vivo. Implementation of these physiologically relevant models, illustrated here in the context of human epithelial tissues, has enabled the study of intrinsic cell regulation pathways and also has provided compelling evidence for the role of the stromal compartment in directing epithelial cell function and dysfunction. Furthermore the experimental accessibility afforded by these tissue-specific 3D models has implications for the design and development of cancer therapies.
The Royal National Throat, Nose and Ear Hospital in World War II: a reminiscence
Authors: Cohen Ben
Published: May 2003

The author describes his personal reminiscences of the Royal National, Throat, Nose and Ear Hospital during World War II. Many of the colourful characters of this era arediscussed.
Surgical intervention in middle-ear cholesterol granuloma
Authors: Maeta Manabu , Saito Ryusuke , Nakagawa Fumio , Miyahara Takakazu
Published: May 2003

Eleven patients who had been surgically treated from 1988 to 1999 were retrospectively reviewed in order to evaluate the efficacy of ventilation tube insertion and mastoidectomy with, or without, mastoid obliteration for intractable middle-ear cholesterol granuloma. The mean age registered was 17.2 years at the time of surgical treatment. All cases were unilaterally affected. Five ears were treated with simple mastoidectomy coupled with the insertion of a ventilation tube, while six others had additional mastoid obliteration. The hearing prognosis was excellent with an improved post-operative hearing level of 16.5 dB (cf. pre-operative 37.7 dB). However, morphological prognosis revealed two ears had a residual perforated tympanic membrane without otorrhoea after displacement of the ventilation tube. Of the remaining nine ears with intact placement of the ventilation tube, five had dry ears while four had occasional otorrhoea. Although the morphological prognosis was incomplete, treatments involving at least aninsertion of a ventilation tube with thorough mastoidectomy were thought to be necessary.
Labyrinthine fistula: a complication of chronic suppurative otitis media
Authors: Grewal D. S. , Hathiram Bachi T. , Dwivedi Ashwani , Kumar Lovneesh , Sheth Kaushal , Srivastava Shobhit
Published: May 2003

A labyrinthine fistula is a frequent complication of long-standing unsafe chronic suppurative otitis media. It is characterized by a slowly progressive erosion of the bony labyrinth. In this paper we present our observations regarding the diagnosis and management in 50 patients with unsafe chronic suppurative otitis media with labyrinthine fistula.
A new and simple modification of the prosthetic voice restoration technique
Authors: Görür Kemal , Özcan Cengiz , Ünal Murat , Özkul M. Doǧan
Published: May 2003

Several problems have been observed when performing the classic endoscopic technique for voice restoration following laryngectomy. An easy and safe method is described for the insertion of a Provox® voice prosthesis using a Yankauer tonsil suction tube and an antrum trocar with an irrigation cannula.
Is the routine use of antibiotics justified in adult tonsillectomy?
Authors: O’Reilly B. J. , Black S. , Fernandes J. , Panesar J.
Published: May 2003

Pain and secondary haemorrhage are the commonest complications of adult tonsillectomy, occurring mostly in the community. This is a randomized, double-blind, placebo-controlled, prospective trial of the effect of perioperative amoxycillin on these complications. The incidence and severity of post-operative haemorrhage was measured. For the first 10 post-operative days patients provided a linear pain score, a record of GP visits, and their use of additional antibiotics and analgesics.

Of 95 patients considered: 23 suffered a secondary haemorrhage; 54 consulted their general practitioner (GP) because of pain; additional antibiotics were used by at least 31 and additional analgesics by at least 41. No significant differences were demonstrated between the active and placebo groups for any of these measures.

This study demonstrates that secondary haemorrhage is common after adult tonsillectomy. Post-operative pain remains a major problem requiring frequent GP consultations. There appears to be no justification for the routine use of perioperative antibiotics.
Occult bronchogenic carcinoma presenting as metastasis to the site of a bone anchored hearing aid
Authors: Hadjihannas Edward , McDermott Ann-Louise , Warfield Adrian T. , Proops David W. , Reid Andrew P.
Published: May 2003

The first report of a patient with metastatic bronchogenic carcinoma of the skin surrounding the abutment of a bone anchored hearing aid (BAHA) is presented. Complications of bone anchored hearing implantation have been well documented to date. We present a 68-year-old lady who presented with an unusual skin lesion surrounding the abutment of her BAHA. This was the first presentation of her bronchogenic tumour.

We also review the literature regarding cutaneous metastasis and complications of BAHA.
Maxillary sinus mucocele presenting as a late complication of a maxillary advancement procedure
Authors: Thio D. , De S. , Phelps P. D. , Bath A. P.
Published: May 2003

Paranasal sinus mucoceles are benign, locally expansile cyst-like masses that are filled with mucus and lined with epithelium. Less than one per cent of them involve the maxillary sinus. Most of these are late complications of a Caldwell Luc procedure. A case is presented of a 31-year-old woman with a maxillary sinus mucocele who had undergone a Le Fort I maxillary advancement procedure 15 years previously – a complication never previously reported.
Primary sinonasal non-Hodgkin’s lymphoma masquerading as chronic rhinosinusitis: an issue of routine histopathological examination
Authors: Chen Shih-Hung , Wu Chuan-Song , Chan Kuang-Han , Hongh Yong-Tsung , Shun Chia-Tung , Liu Chia-Ming
Published: May 2003

Primary non-Hodgkin’s lymphoma (NHL) of the sinonasal tract is uncommon. Morphologically and radiographically, sinonasal lymphomas are difficult to distinguish fromother malignant neoplasms or non-neoplastic processes. However, there is no general consensus about the need of routine histopathological examination for nasal polyps among otolaryngologists. We present a case of primary sinonasal NHL mimicking chronic hinosinusitis and debate the issue of routine histopathological examination. We suggest that all tissues removed from the sinonasal tract during surgery must be submitted for histopathological examination. Failure to do so may miss diagnosis and delay appropriate treatment.
Eosinophilic angiocentric fibrosis
Authors: Tabaee Abtin , Zadeh Mani H. , Proytcheva Maria , LaBruna Anthony
Published: May 2003

Eosinophilic angiocentric fibrosis of the upper respiratory tract is a rare disorder of unknown aetiology. Despite characteristic histological findings, the aetiology and management of this lesion remain unclear. We describe a case of nasal eosinophilic angiocentric fibrosis and discuss possible demographic and aetiological patterns.
Bilateral vocal fold palsy caused by chronic motor axonal neuropathy
Authors: Marchant H. , Supiot F. , Choufani G. , Hassid S.
Published: May 2003

The authors report a first case of chronic motor axonal neuropathy involving ENT manifestations, in a 64-year-old male presenting with gait difficulties, effort dyspnoea and dysphonia. Eleven months after the first symptoms, he developed severe hypoventilation, limb weakness and bilateral vocal fold palsy and had to be intubated for respiratory failure. The diagnosis of chronic motor axonal neuropathy was suspected on clinical and electrophysiological grounds. The patient improved dramatically after a five-day course of 0.4 g/kg intravenous immunoglobulin. He is still being treated with methylprednisolone 0.5 mg/kg every other day and remains stable.

We conclude the bilateral vocal fold palsy may be associated with chronic motor axonal neuropathy and that the immunosuppressive treatment may be effective in such cases.
Disseminated septicaemic melioidosis: an unusual presentation of masticator space infection
Authors: Srirompotong Somchai , Reechaipichitkul Wisoot
Published: May 2003

Melioidosis is an infectious disease caused by a saprophytic bacterium, Burkholderia pseudomallei. It is endemic to Southeast Asia and Northern Australia. The spectrum of melioidosis in humans varies from sub-clinical to overwhelming protean manifestations resembling other acute and chronic bacterial infections. Disseminated septicaemia melioidosis presenting as a masticator space infection is reported here. This is germane to those treating diabetic patients with deep neck infections living in, or having visited, areas endemic for B. pseudomallei.
Synchronous bilateral mucoepidermoid carcinoma of the parotid gland
Authors: Hakuba Nobuhiro , Hyodo Masamitsu
Published: May 2003

It is rare for a parotid gland tumour to arise bilaterally, the most common example being Warthin’s tumour. Furthermore, it is rare for a parotid gland cancer to occur bilaterally. Here, we describe a case of synchronous bilateral mucoepidermoid carcinoma arising in the parotid gland. A case of bilateral facial nerve dysfunction is presented in which aggressive surgery failed to save the life of a 48-year-old man. This is the first such case reported in the available English literature.
Effects of Static Compression on the Vibration Modes of a Fingertip
Authors: Wu John Z. , Rakheja Subhash , Dong Ren G. , Smutz W. Paul
Published: May 2003

The vibrotactile perception threshold measurement technique is used to diagnose sensory neuropathy of the hand. The vibration perception threshold of a human finger could be most sensitive in the vicinity of one or more of its resonant frequency. The purpose of the present study is to investigate, theoretically, the effects of deformation (compression) on the free vibration behaviour of fingertips. An in-plane finite element model of the fingertip tissue has been formulated on the basis of the anatomical structure and the nonlinear elastic material properties of the soft tissue. The vibration modes of a fingertip model have been analyzed under different deformation states. Our results show that the modal vibration characteristics of the fingertip are deformation-dependent; the eigenfrequencies of the fingertip increase with the increasing preload. The present study suggests, from a theoretical point of view, that the static deformation state will influence the vibration modes and thus the perception threshold of fingertips.
Vortex Design and Outlet Blade Angles of HAWT Turbines
Authors: Ntoko Nzumbe-Mesape
Published: May 2003

Using the vortex specification, the expression outlet for the blade angle of a HAWT turbine blade element is shown to exhibit a minimum that has some implications for design.
Study of Aerodynamic Forces on a Rotating Wind Driven Ventilator
Authors: Rashid D. M. H. , Ahmed N. A.
Published: May 2003

A wind driven ventilator is a simple, cost-effective and environmentally-friendly device that can improve comfort and the working environment. Unfortunately very little is known about the complex flow field associated with the operation of this device. A wind tunnel investigation of the flow associated with a rotating wind ventilator was, therefore, carried out at the aerodynamic laboratory of the University of New South Wales within the Reynolds number range of 1.1 times 105 to 5.5 times 105. An attempt was also made to study some of the important features associated with operation of a rotating wind ventilator using a simple model of a stationary and a spinning cylinder. The results were encouraging and several flow features were identified for future improvement in the performance of a wind ventilator.
Self-Administered Medication-Risk Questionnaire in an Elderly Population
Authors: Levy Hedva Barenholtz
Published: May 2003

OBJECTIVE:

To evaluate and validate a 10-item self-administered questionnaire for use by elderly patients to identify who is at increased risk of potentially experiencing a medication-related problem (MRP).

METHODS:

Forty participants aged ≥60 years who took ≥2 prescription drugs regularly completed the questionnaire. Data collection was based on patient interviews, review of pharmacy or medical records, and drug regimen reviews (DRRs). Outcome measures included feasibility, inter-rater reliability, test–retest reliability, internal consistency, and validity of the questionnaire. DRR severity scores were determined for each participant based on published guidelines for appropriate use.

RESULTS:

The questionnaire was easily administered to this group of older adults. Overall inter-rater reliability was high (r = 0.847). Nine of 10 individual questions matched well between the investigator and participants (κ 0.4–0.6 for 3 questions; >0.6 for 6 questions). Test–retest reliability was significant for all 10 questions (κ > 0.6). Internal consistency was acceptable (a = 0.69). DRR severity scores were correlated with questionnaire responses to determine validity. The number of yes answers correlated significantly with higher DRR severity scores (p < 0.001). Furthermore, 5 individual questions significantly correlated with DRR severity scores.

CONCLUSIONS:

This study suggests that a self-administered questionnaire can be used in an older adult population to identify patients potentially at increased risk of MRPs. Clinicians in ambulatory care settings with similar patient populations can use a modified form of the questionnaire to screen for patients who should receive a medication review.
Dapsone-Induced Sulfone Syndrome
Authors: Lee Kimberly B , Nashed Trisha B
Published: May 2003

OBJECTIVE:

To report a patient with dapsone-induced sulfone syndrome.

CASE SUMMARY:

A 42-year-old HIV-infected African American man developed fever, lymphadenopathy, exfoliative dermatitis, hepatitis, and methemoglobinemia 4 weeks after starting dapsone. Complete resolution of symptoms and laboratory abnormalities occurred with cessation of dapsone therapy.

DISCUSSION:

Sulfone syndrome is not a well-known sequela of dapsone therapy. It is not dose-related, usually occurs in doses of 50–300 mg/d, all cases occur within 2 months of starting dapsone, all patients have fever, and most patients will develop rash and evidence of hepatic injury. The temporal relationship between dapsone therapy and onset of clinical symptoms and objective data led us to believe that dapsone caused sulfone syndrome in our patient. An objective causality assessment revealed that the adverse drug event was probable.

CONCLUSIONS:

Although sulfone syndrome appears to be relatively uncommon, healthcare practitioners must be aware of the potentially fatal syndrome associated with dapsone use.
Improving Adherence and Reducing Medication Discrepancies in Patients with Diabetes
Authors: Grant Richard W , Devita Nicole G , Singer Daniel E , Meigs James B
Published: May 2003

OBJECTIVE:

To improve medication adherence by reducing self-reported adherence barriers, and to identify medication discrepancies by comparing physician-prescribed and patient-reported medical regimens.

DESIGN:

Prospective, randomized, controlled trial.

SETTING AND PARTICIPANTS:

A single academically affiliated community health center. Eligible patients had type 2 diabetes, had undergone laboratory testing in the year preceding the study, and had visited the clinic in the 6 months preceding the study.

INTERVENTION:

A pharmacist administered detailed questionnaires, provided tailored education regarding medication use and help with appointment referrals, and created a summary of adherence barriers and medication discrepancies that was entered into the medical record and electronically forwarded to the primary care provider.

MEASUREMENTS:

Changes in self-reported adherence rates and barriers were compared 3 months after the initial interview. Intervention patients with medication discrepancies at baseline were assessed for resolution of discrepancies at 3 months.

RESULTS:

Rates of self-reported medication adherence were very high and did not improve further at 3 months (6.9 of 7 d, with all medicines taken as prescribed; p = 0.3). Medical regimen discrepancies were identified in 44% of intervention patients, involving 45 doses of medicines. At 3-month follow-up, 60% of discrepancies were resolved by corrections in the medical record, while only 7% reflected corrections by patients.

CONCLUSIONS:

In this community cohort, patients reported few adherence barriers and very high medication adherence rates. Our patient-tailored intervention did not further reduce these barriers or improve self-reported adherence. The high prevalence of medication discrepancies appeared to mostly reflect inaccuracies in the medical record rather than patient errors.
Bupropion Overdose: QTc Prolongation and its Clinical Significance
Authors: Isbister Geoffrey K , Balit Corrine R
Published: May 2003

OBJECTIVE:

To investigate the cardiotoxicity of bupropion hydrochloride in deliberate self-poisoning.

METHODS:

A prospective study was conducted in a national poisons information center (PIC) of cases of adult deliberate self-poisoning with medical record follow-up of the patients. Fifty-nine cases of bupropion deliberate self-poisoning managed in the hospital, in which the New South Wales PIC was contacted for advice, were evaluated from November 2000 through July 2001. Clinical effects and electrocardiographic (ECG) parameters (QRS, QT, QTc) were the main outcome measures.

RESULTS:

ECGs were available for 17 of the 59 patients for analysis, 9 patients (53%) were women, and median patient age was 28 years (interquartile range 22–37). The mean ± SD ingested bupropion dose was 3.8 ± 3.1 g. Tachycardia occurred in 13 patients (76%; 95% CI 50 to 93) and hypertension in 8 patients (47%). There were no reports of hypotension or arrhythmias. There was a significantly increased QTc of 461 ± 34 msec in the patients with bupropion overdose compared with previously developed controls; 13 of the 17 cases had a QTc >440 msec (76%; 95% CI 50 to 93). The uncorrected QT interval did not differ from that of controls.

CONCLUSIONS:

A moderately prolonged QTc (>440 msec) is common in bupropion overdose. However, this may not be a result of intrinsic cardiac toxicity, but overcorrection of the QTc due to the tachycardia that occurs. It is important that the QTc is interpreted with caution in overdoses of agents that cause significant tachycardia (>100 beats/min).
Valsartan-Induced Angioedema
Authors: Irons Brian K , Kumar Ashwani
Published: May 2003

OBJECTIVE:

To report a case of dose-dependent angioedema secondary to the use of the angiotensin-receptor blocker (ARB) valsartan.

CASE SUMMARY:

A 64-year-old Hispanic woman presented with swelling of the lips shortly after an increase in her valsartan dose for uncontrolled hypertension. Other potential causes were not identified. The angioedema subsequently resided after a dosage reduction and observation. Use of the Naranjo probability scale indicated a probable relationship between the angioedema and valsartan therapy in this patient.

DISCUSSION:

Drug-induced angioedema is often associated with the use of angiotensin-converting enzyme (ACE) inhibitors and is probably secondary to their effects on bradykinin levels. ARBs are thought to produce few, if any, cases of angioedema if excess bradykinin levels are the root cause of angioedema secondary to ACE inhibitor use. Several potential ARB-induced cases of angioedema have been reported. The exact mechanism of angioedema induced by drugs in both of these classes is unknown. Animal data suggest that there may be a relationship between ARB use and increased tissue bradykinin levels secondary to stimulation of angiotensin II AT2 receptors.

CONCLUSIONS:

This is the third reported case of valsartan-induced angioedema and the first thought to be dose dependent. Practitioners should be aware of this potential adverse effect of valsartan, although the underlying cause is still not known.
The 10 Å to 7 Å Halloysite Transition in a Tropical Soil Sequence, Costa Rica
Authors: Kautz Christopher Q. , Ryan Peter C.
Published: May 2003

Soils developed on Pleistocene andesitic lava flows and fluvial detritus in the Atlantic coastal plain of Costa Rica display a clay mineral assemblage that includes 10 Å and 7 Å halloysite and lesser amounts of kaolinite and dioctahedral vermiculite. Other secondary minerals include gibbsite, goethite, hematite, maghemite, allophane and amorphous Al hydroxides. Active floodplain soils are dominated by 10 Å halloysite and contain less allophane, while soil clays from Pleistocene terraces consist of a mixture of 10 Å and 7 Å halloysite as well as less dioctahedral vermiculite, kaolinite, and amorphous Al hydroxides. Residual soils formed on Pleistocene lava flows are dominated by 7 Å halloysite with less abundant kaolinite, dioctahedral vermiculite, 10 Å halloysite and amorphous Al hydroxides. This sequence suggests transformations of 10 Å halloysite to 7 Å halloysite and allophane to amorphous Al hydroxides with time. The presence of 10 Å halloysite in Pleistocene terrace soils implies slow reaction rates or metastability.

Quantitative X-ray diffraction (QXRD) analysis indicates a decrease in the amount of plagioclase feldspar from 34 wt.% in the 1–2 year floodplain to 0–1.6% in terrace and residual soils. Plagioclase weathering is paralleled by the formation of dioctahedral clay, allophane and Al hydroxides. Analysis by QXRD also indicates that crystalline minerals comprise 70–95% of the soil fraction, implying 5–30% X-ray-amorphous material. These data are verified by selective extraction using ammonium oxalate, which indicates 8–30% amorphous material. Chemical analysis of the extractant by inductively coupled plasmaatomic emission spectrometry indicates that allophane (Al:Si ratios of 0.92–3.82) occurs in floodplain and some terrace soils while amorphous Al hydroxides appear to coexist with allophane in Pleistocene terrace and residual soils with Al:Si ratios of 6.53–8.53. Retention of Mg to a greater extent than Na, Ca and K suggests Mg incorporation into hydroxide sheets in dioctahedral vermiculite as well as substitution into hydroxides.
Structural Transformations of Clay Minerals in Soils of a Climosequence in an Italian Alpine Environment
Authors: Mirabella Aldo , Egli Markus
Published: May 2003

Clays of a soil sequence with five profiles in the Val Genova (northern Italy) along an elevation gradient with climate ranging from moderate to Alpine were investigated with XRD using several diagnostic treatments. Smectites developed in the surface horizons of podzolic soils either from chlorite through the removal of hydroxy interlayers or from mica, which weathers in a first step to regularly or irregularly interstratified clay minerals. Citrate treatment allowed the detection of low-charge expandable minerals in the Bhs or Bs horizons. Therefore, the reduction of the charge of 2:1 clay minerals occurred before the removal of hydroxy polymers by fulvic acids and low-weight organic acids. Due to the more intense podzolization process near the tree line, the d060 region showed a temporal evolution of trioctahedral to dioctahedral mineral structures in the well developed Podzols. The pedogenic smectites of the E or Bhs horizons generally included one or several populations with various charges. In most cases, smectite was a heterogeneous mixture of montmorillonite and interstratified beidellite-montmorillonite. A pure beidellite phase could not be detected. The soils near the tree line, where weathering processes were most intense, had two main components: one with a charge >0.75, representing vermiculite-like minerals, and the other with a charge near 0.25, representing smectite. The charges of the beidellitic component and montmorillonite were almost equal. The higher the weathering state of the investigated soils, the lower was the layer charge of smectites.
Measurement of Illite Particle Thickness using a Direct Fourier Transform of Small-Angle X-ray Scattering Data
Authors: Shang Chao , Rice James A. , Eberl Dennis D. , Lin Jar-Shyong
Published: May 2003

It has been suggested that interstratified illite-smectite (I-S) minerals are composed of aggregates of fundamental particles. Many attempts have been made to measure the thickness of such fundamental particles, but each of the methods used suffers from its own limitations and uncertainties. Small-angle X-ray scattering (SAXS) can be used to measure the thickness of particles that scatter X-rays coherently. We used SAXS to study suspensions of Na-rectorite and other illites with varying proportions of smectite. The scattering intensity (I) was recorded as a function of the scattering vector, q = (4 π/λ) sin(θ/2), where λ is the X-ray wavelength and θ is the scattering angle. The experimental data were treated with a direct Fourier transform to obtain the pair distance distribution function (PDDF) that was then used to determine the thickness of illite particles. The Guinier and Porod extrapolations were used to obtain the scattering intensity beyond the experimental q, and the effects of such extrapolations on the PDDF were examined. The thickness of independent rectorite particles (used as a reference mineral) is 18.3 Å. The SAXS results are compared with those obtained by X-ray diffraction peak broadening methods. It was found that the power-law exponent (α) obtained by fitting the data in the region of q = 0.1–0.6 nm−1 to the power law (I = I0q−α) is a linear function of illite particle thickness. Therefore, illite particle thickness could be predicted by the linear relationship as long as the thickness is within the limit where α <4.0.
The Visible Diffuse Reflectance Spectrum in Relation to the Color and Crystal Properties of Hematite
Authors: Torrent José , Barrón Vidal
Published: May 2003

Hematite (α-Fe2O3) possesses distinct spectral properties which facilitate its identification in mineral mixtures. This paper reports the relationships between the visible diffuse reflectance (DR) spectrum and the color and crystal properties of a group of 81 natural and synthetic hematites. The visible DR spectra for powdered hematite samples diluted to 4 wt.% with BaSO4 white standard were recorded and used to calculate the corresponding Munsell colors. The second derivative of the Kubelka-Munk function of the DR was used to estimate the position and intensity of the main absorption bands, which occurred at ∼435, ∼485 and ∼545 nm. The Munsell hue ranged from 9.5P to 5.3YR and was negatively correlated with the position of the ∼545 nm band, so it became yellower as the band shifted to shorter wavelengths (higher energies). The Munsell value, which ranged from 4.9 to 8.6, and chroma, which ranged from 1.4 to 8.3, were negatively and positively correlated, respectively, with the intensity of the ∼545 nm band, the position of which exhibited a weak negative correlation with the degree of Al substitution (x). The position and intensity of this band also exhibited a weak negative correlation with the specific surface area (SSA); both, however, were uncorrelated with domain shape as measured by the ratio between the X-ray mean coherence lengths (MCLs) in the [110] and [104] directions. The properties of the ∼435 and ∼485 nm bands were unrelated to x, SSA or MCL110/MCL104. The negative relationship between the position of the ∼545 nm band and x does not support the assignment of this band to the 2(6A1) → 2(4T1g(4G)) electron pair transition (EPT), which relates to the to Fe3+−Fe3+ magnetic coupling between face-sharing octahedra. The ∼485 nm band might reflect a ‘goethitic’ structural component in Fe-defective hematites as it appears at the same wavelength as the hypothetical EPT related to Fe3+−Fe3+ magnetic coupling between edge-sharing octahedra in goethite (α-FeOOH).
Anionic Polyacrylamide Polymer Adsorption by Pyrophyllite and Montmorillonite
Authors: Heller Hadar , Keren Rami
Published: May 2003

The mechanism by which the anionic polymers interact with platelets of 2:1 clay minerals is not fully understood. The objective of the present study was to evaluate the effect of the electric field associated with the basal and edge surfaces of the clay minerals on the adsorption of anionic polymers. Two negatively charged polymers, PAM90 and ACC86, of the same molecular weig ht (2 × 105 g mol−1) but with different degrees of hydrolysis (90 and 20%, respectively), were used. The effect of pH (6, 10), NaCl concentration (0, 10 mmolC L−1) and clay particle size on PAM90 adsorption by pyrophyllite and the effect of NaCl concentration on the adsorption of these polymers by Na-montmorillonite in aqueous suspensions were studied. Adsorption of PAM90 on pyrophyllite was greater at pH 6 than at pH 10 and greater in 10 mmol L−1 NaCl than in distilled water. Adsorption of PAM90 on pyrophyllite increased with decreasing particle size. On pyrophyllite the high-charge-density PAM90 was adsorbed to a greater extent than the low-charge-density ACC86; by contrast, ACC86 adsorption was greater than that of PAM90 on Na-montmorillonite. These results were attributed to the repulsive forces which develop between the negatively charged extended-chain polymer and the extended negative electric field associated with the basal surfaces, around the Na-montmorillonite platelets. The results may suggest that the edge surfaces play a major role in PAM adsorption.
Indirect lead exposure among children of radiator repair workers
Authors: Aguilar‐Garduño C. , Lacasaña M. , Tellez‐Rojo M.M. , Aguilar‐Madrid G. , Sanin‐Aguirre L.H. , Romieu I. , Hernandez‐Avila M.
Published: May 2003

Background

Secondary exposure to lead has been identified as a public health problem since the late 1940s; we investigate the risk of lead exposure among families of radiator repair workers.

Methods

A sample of the wives and children, aged 6 months to 6 years (exposed children) (n = 19), of radiator repair workers and a sample of children whose parents were not occupationally exposed to lead (non‐exposed children) (n = 29) were matched for age and residence; their geometric mean blood lead levels are compared. Blood samples were obtained by the finger stick method and environmental dust samples by the wipe method; both were analyzed using a portable anodic stripping voltameter.

Results

Dust lead levels were significantly higher in the houses of exposed children (143.8 vs. 3.9 μg/g; P < 0.01). In crude analyses, the highest lead levels were observed among children whose fathers worked in home‐based workshops (22.4 μg/dl)(n = 6). Children whose fathers worked in an external workshop (n = 13) also had high levels (14.2 μg/dl) (P < 0.01), while blood lead levels in non‐exposed children were significantly lower (5.6 μg/dl)(P < 0.01). The observed differences remained significant after adjustment for age and gender.

Conclusions

This study confirms that children of radiator repair workers are at increased risk of lead exposure and public health interventions are needed to protect them. Am. J. Ind. Med. 43:662–667, 2003. © 2003 Wiley‐Liss, Inc.