bluuebunny/crossref_metadata_2025 huggingface dataset:
Differential maternal investment counteracts for late breeding in magpiesPica pica: an experimental study
Authors: De Neve Liesbeth , J. Soler Juan , Soler Manuel , Pérez‐Contreras Tomás
Published: April 2004

Reproductive success in many avian populations declines throughout the breeding season. Two hypotheses have gained attention to explain such a decline: the “timing” hypothesis proposes that deteriorating food availability causes the decline in reproductive success (causal effect of breeding time), whereas the “quality” hypothesis proposes that individuals of lower phenotypic quality reproduce at the end of the breeding season, causing the correlation between breeding time and breeding success. We tested both of these hypotheses in a monogamous single breeder, the magpiePica pica, by experimentally inducing some pairs to lay a replacement clutch, after removal of the first clutch. The first clutch was left in the nest of another magpie pair (matched by laying date and clutch size), and incubated and raised by these foster parents. In this way we obtained two clutches from the same magpie pair with full siblings raised in conditions of the first and second reproductive attempts. High quality pairs (with laying dates in the first half of the breeding season) reached similar breeding success in replacement clutches as compared to first clutches of the same female. In addition, experimental pairs reared significantly more offspring of similar quality in their replacement clutches as compared to late‐season first clutches, thereby suggesting that late season first clutches were produced by pairs of lower phenotypic quality. Results indicate that high quality pairs trade‐off clutch size for larger eggs in replacement clutches, which could help magpie pairs to partly compensate for poorer environmental conditions associated with a delayed breeding attempt.
Phylogenetic relationships of woodcreepers (Aves: Dendrocolaptinae) – incongruence between molecular and morphological data
Authors: Irestedt Martin , Fjeldså Jon , Ericson Per G. P.
Published: April 2004

The woodcreepers is a highly specialized lineage within the New World suboscine radiation. Most systematic studies of higher level relationships of this group rely on morphological characters, and few studies utilizing molecular data exist. In this paper, we present a molecular phylogeny of the major lineages of woodcreepers (Aves: Dendrocolaptinae), based on nucleotide sequence data from a nuclear non‐coding gene region (myoglobin intron II) and a protein‐coding mitochondrial gene (cytochrome b). A good topological agreement between the individual gene trees suggests that the resulting phylogeny reflects the true evolutionary history of woodcreepers well. However, the DNA‐based phylogeny conflicts with the results of a parsimony analysis of morphological characters. The topological differences mainly concern the basal branches of the trees. The morphological data places the genus Drymornis in a basal position (mainly supported by characters in the hindlimb), while our data suggests it to be derived among woodcreepers. Unlike most other woodcreepers, Drymornis is ground‐adapted, as are the ovenbirds. The observed morphological similarities between Drymornis and the ovenbird outgroup may thus be explained with convergence or with reversal to an ancestral state. This observation raises the question of the use of characters associated with locomotion and feeding in phylogenetic reconstruction based on parsimony.
Green woodhoopoe Phoeniculus purpureus territories remain stable despite group‐size fluctuations
Authors: Radford Andrew N. , Du Plessis Morné A.
Published: April 2004

Cooperatively breeding groups may be constrained in size by the territory available to them, or territories may be expanded to accommodate extra group members. Here, we show that there was no relationship between the number of adult green woodhoopoes Phoeniculus purpureus in a group and the size of its territory. Furthermore, territories were remarkably stable between seasons, with no significant changes in area, despite fluctuating group sizes. These results suggest that food was not limiting at the group sizes found in this study: sufficient resources were available within existing territories for groups that were expanding in size. Following an increase in group membership, a larger proportion of the available area was utilised. Groups also used a larger area in the non‐breeding season compared to when breeding: in the latter instance, foraging was concentrated in the vicinity of the nest.
Winter segregation of migrant European robins Erithacus rubecula in relation to sex, age and size
Authors: Catry Paulo , Campos Ana , Almada Vítor , Cresswell Will
Published: April 2004

Birds often show some form of social segregation during winter, both at large geographical scales (a consequence of differential migration) and at the regional or local level, when comparing different habitats or micro‐habitats. However, our understanding of the mechanisms underlying such patterns is still poor. These issues have been rarely investigated in migratory Old‐World passerines, particularly with respect to differences between the sexes. In this study, we show that female European robins Erithacus rubecula (sexed by molecular techniques) greatly outnumber males in southern Iberia, which confirms that this species is a differential migrant with a strong latitudinal segregation of the sexes. Furthermore, sex, age and body size influence the habitat distribution of robins in winter. Subordinate birds (females, juveniles and small individuals) were generally more common in habitats with a greater shrub development, and comparatively scarce in woodlands with relatively little undergrowth. Birds wintering in woodlands were in better condition (assessed by breast‐muscle scoring) than birds wintering in shrubland. These results are consistent with the hypothesis that proposes that social dominance, mediated by differences in size and experience, is important in determining the habitat segregation of sex and age classes. The alternative hypothesis (habitat specialization), although not specifically supported by our findings, cannot be ruled out on the basis of the available evidence.
Understanding avian nest predation: why ornithologists should study snakes
Authors: Weatherhead Patrick J. , Blouin‐Demers Gabriel
Published: April 2004

Despite the overriding importance of nest predation for most birds, our understanding of the relationship between birds and their nest predators has been developed largely without reliable information on the identity of the predators. Miniature video cameras placed at nests are changing that situation and in six of eight recent studies of New World passerine birds, snakes were the most important nest predators. Several areas of research stand to gain important insights from understanding more about the snakes that prey on birds' nests. Birds nesting in fragmented habitats often experience increased nest predation. Snakes could be attracted to habitat edges because they are thermally superior habitats, coincidentally increasing predation, or snakes could be attracted directly by greater prey abundance in edges. Birds might reduce predation risk from snakes by nesting in locations inaccessible to snakes or in locations that are thermally inhospitable to snakes, although potentially at some cost to themselves or their young. Nesting birds should also modify their behavior to reduce exposure to visually orienting snakes. Ornithologists incorporating snakes into their ecological or conservation research need to be aware of practical considerations, including sampling difficulties and logistical challenges associated with quantifying snake habitat use.
Cloning, expression and characterization of two new IgE‐binding proteins from the yeast Malassezia sympodialis with sequence similarities to heat shock proteins and manganese superoxide dismutase
Authors: Andersson Anna , Rasool Omid , Schmidt Margit , Kodzius Rimantas , Flückiger Sabine , Zargari Arezou , Crameri Reto , Scheynius Annika
Published: April 2004

Malassezia sympodialis is an opportunistic yeast that colonizes human skin and may induce IgE and T cell reactivity in patients with atopic eczema/dermatitis syndrome (AEDS). Previously, we have cloned and expressed six recombinant allergens (rMala s 1 and rMala s 5 to rMala s 9) from this yeast. By combining high throughput screening and phage surface display techniques, 27 complete and partial IgE‐binding clones of M. sympodialis have been identified. Here we enlarged the panel of recombinant M. sympodialis allergens by RACE–PCR, cloning and nucleotide sequencing to obtain the coding sequences of two new IgE‐binding clones. The coding sequences of one of the clones showed similarity to the heat shock protein (HSP) family and the other to manganese superoxide dismutase (MnSOD), and both had a high degree of homology to human counterparts. The coding sequences were expressed in Escherichia coli as six‐histidine tagged recombinant proteins and generated products with molecular masses of 86.1 kDa for HSP and 22.4 kDa for MnSOD. Their IgE‐binding frequencies were shown to be 69% and 75%, respectively, to 28 sera from AEDS patients with serum IgE to M. sympodialis extract, indicating that HSP and MnSOD are major M. sympodialis allergens. In inhibition immunoblotting, M. sympodialis extract could inhibit the binding of serum IgE from AEDS patients to rHSP and rMnSOD in a concentration‐dependent manner. The high frequency of sera from AEDS patients, showing IgE binding to both HSP and MnSOD, indicates that these allergens, designated Mala s 10 and Mala s 11, could play a role in AEDS.
Structure and topology of the transmembrane domain 4 of the divalent metal transporter in membrane‐mimetic environments
Authors: Li Hongyan , Li Fei , Qian Zhong Ming , Sun Hongzhe
Published: April 2004

The divalent metal transporter (DMT1) is a 12‐transmembrane domain protein responsible for dietary iron uptake in the duodenum and iron acquisition from transferrin in peripheral tissues. The transmembrane domain 4 (TM4) of DMT1 has been shown to be crucial for its biological function. Here we report the 3D structure and topology of the DMT1‐TM4 peptide by NMR spectroscopy with simulated annealing calculations in membrane‐mimetic environments, e.g. 2,2,2‐trifluoroethanol and SDS micelles. The 3D structures of the peptide are similar in both environments, with nonordered and flexible N‐ and C‐termini flanking an ordered helical region. The final set of the 16 lowest energy structures is particularly well defined in the region of residues Leu9–Phe20 in 2,2,2‐trifluoroethanol, with a mean pairwise root mean square deviation of 0.23 ± 0.10 Å for the backbone heavy atoms and 0.82 ± 0.17 Å for all heavy atoms. In SDS micelles, the length of the helix is dependent on pH values. In particular, the C‐terminus becomes well‐structured at low pH (4.0), whereas the N‐terminal segment (Arg1–Gly7) is flexible and poorly defined at all pH values studied. The effects of 12‐doxylPtdCho spin‐label and paramagnetic metal ions on NMR signal intensities demonstrated that both the N‐terminus and helical region of the TM4 are embedded into the interior of SDS micelles. Unexpectedly, we observed that amide protons exchanged much faster in SDS than in 2,2,2‐trifluoroethanol, indicating that there is possible solvent accessibility in the structure. The paramagnetic metal ions broaden NMR signals from residues both situated in aqueous phase and in the helical region. From these results we speculate that DMT1‐TM4s may self‐assemble to form a channel through which metal ions are likely to be transported. These results might provide an insight into the structure‐function relationship for the integral DMT1.
Purification and characterization of Helicobacter pylori arginase, RocF: unique features among the arginase superfamily
Authors: McGee David J. , Zabaleta Jovanny , Viator Ryan J. , Testerman Traci L. , Ochoa Augusto C. , Mendz George L.
Published: April 2004

The urea cycle enzyme arginase (EC 3.5.3.1) hydrolyzes l‐arginine to l‐ornithine and urea. Mammalian arginases require manganese, have a highly alkaline pH optimum and are resistant to reducing agents. The gastric human pathogen, Helicobacter pylori, also has a complete urea cycle and contains the rocF gene encoding arginase (RocF), which is involved in the pathogenesis of H. pylori infection. Its arginase is specifically involved in acid resistance and inhibits host nitric oxide production. The rocF gene was found to confer arginase activity to Escherichia coli; disruption of plasmid‐borne rocF abolished arginase activity. A translationally fused His6–RocF was purified from E. coli under nondenaturing conditions and had catalytic activity. Remarkably, the purified enzyme had an acidic pH optimum of 6.1. Both purified arginase and arginase‐containing H. pylori extracts exhibited optimal catalytic activity with cobalt as a metal cofactor; manganese and nickel were significantly less efficient in catalyzing the hydrolysis of arginine. Viable H. pylori or E. coli containing rocF had significantly more arginase activity when grown with cobalt in the culture medium than when grown with manganese or no divalent metal. His6–RocF arginase activity was inhibited by low concentrations of reducing agents. Antibodies raised to purified His6–RocF reacted with both H. pylori and E. coli extracts containing arginase, but not with extracts from rocF mutants of H. pylori or E. coli lacking the rocF gene. The results indicate that H. pylori RocF is necessary and sufficient for arginase activity and has unparalleled features among the arginase superfamily, which may reflect the unique gastric ecological niche of this organism.
Characterization of a digestive carboxypeptidase from the insect pest corn earworm (Helicoverpa armigera) with novel specificity towards C‐terminal glutamate residues
Authors: Bown David P. , Gatehouse John A.
Published: April 2004

Carboxypeptidases were purified from guts of larvae of corn earworm (Helicoverpa armigera), a lepidopteran crop pest, by affinity chromatography on immobilized potato carboxypeptidase inhibitor, and characterized by N‐terminal sequencing. A larval gut cDNA library was screened using probes based on these protein sequences. cDNA HaCA42 encoded a carboxypeptidase with sequence similarity to enzymes of clan MC [Barrett, A. J., Rawlings, N. D. & Woessner, J. F. (1998) Handbook of Proteolytic Enzymes. Academic Press, London.], but with a novel predicted specificity towards C‐terminal acidic residues. This carboxypeptidase was expressed as a recombinant proprotein in the yeast Pichia pastoris. The expressed protein could be activated by treatment with bovine trypsin; degradation of bound pro‐region, rather than cleavage of pro‐region from mature protein, was the rate‐limiting step in activation. Activated HaCA42 carboxypeptidase hydrolysed a synthetic substrate for glutamate carboxypeptidases (FAEE, C‐terminal Glu), but did not hydrolyse substrates for carboxypeptidase A or B (FAPP or FAAK, C‐terminal Phe or Lys) or methotrexate, cleaved by clan MH glutamate carboxypeptidases. The enzyme was highly specific for C‐terminal glutamate in peptide substrates, with slow hydrolysis of C‐terminal aspartate also observed. Glutamate carboxypeptidase activity was present in larval gut extract from H. armigera. The HaCA42 protein is the first glutamate‐specific metallocarboxypeptidase from clan MC to be identified and characterized. The genome of Drosophila melanogaster contains genes encoding enzymes with similar sequences and predicted specificity, and a cDNA encoding a similar enzyme has been isolated from gut tissue in tsetse fly. We suggest that digestive carboxypeptidases with sequence similarity to the classical mammalian enzymes, but with specificity towards C‐terminal glutamate, are widely distributed in insects.
Transport of the phosphonodipeptide alafosfalin by the H+/peptide cotransporters PEPT1 and PEPT2 in intestinal and renal epithelial cells
Authors: Neumann Jana , Bruch Mandy , Gebauer Sabine , Brandsch Matthias
Published: April 2004

The interaction of the antibacterial phosphonodipeptide alafosfalin with mammalian H+/peptide cotransporters was studied in Caco‐2 cells, expressing the low‐affinity intestinal type peptide transporter 1 (PEPT1), and SKPT cells, expressing the high‐affinity renal type peptide transporter 2 (PEPT2). Alafosfalin strongly inhibited the uptake of [14C]glycylsarcosine with Ki values of 0.19 ± 0.01 mm and 0.07 ± 0.01 mm for PEPT1 and PEPT2, respectively. Saturation kinetic studies revealed that in both cell types alafosfalin affected only the affinity constant (Kt) but not the maximal velocity (Vmax) of glycylsarcosine (Gly‐Sar) uptake. The inhibition constants and the competitive nature of inhibition were confirmed in Dixon‐type experiments. Caco‐2 cells and SKPT cells were also cultured on permeable filters: apical uptake and transepithelial apical to basolateral flux of [14C]Gly‐Sar across Caco‐2 cell monolayers were reduced by alafosfalin (3 mm) by 73%. In SKPT cells, uptake of [14C]Gly‐Sar but not flux was inhibited by 61%. We found no evidence for an inhibition of the basolateral to apical uptake or flux of [14C]Gly‐Sar by alafosfalin. Alafosfalin (3 mm) did not affect the apical to basolateral [14C]mannitol flux. Determined in an Ussing‐type experiment with Caco‐2 cells cultured in Snapwells™, alafosfalin increased the short‐circuit current through Caco‐2 cell monolayers. We conclude that alafosfalin interacts with both H+/peptide symporters and that alafosfalin is actively transported across the intestinal epithelium in a H+‐symport, explaining its oral availability. The results also demonstrate that dipeptides where the C‐terminal carboxyl group is substituted by a phosphonic function represent high‐affinity substrates for mammalian H+/peptide cotransporters.
Biophysical characterization of the interaction of Limulus polyphemus endotoxin neutralizing protein with lipopolysaccharide
Authors: Andrä Jörg , Garidel Patrick , Majerle Andreja , Jerala Roman , Ridge Richard , Paus Erik , Novitsky Tom , Koch Michel H. J. , Brandenburg Klaus
Published: April 2004

Endotoxin‐neutralizing protein (ENP) of the horseshoe crab is one of the most potent neutralizers of endotoxins [bacterial lipopolysaccharide (LPS)]. Here, we report on the interaction of LPS with recombinant ENP using a variety of physical and biological techniques. In biological assays (Limulus amebocyte lysate and tumour necrosis factor‐α induction in human mononuclear cells), ENP causes a strong reduction of the immunostimulatory ability of LPS in a dose‐dependent manner. Concomitantly, the accessible negative surface charges of LPS and lipid A (zeta potential) are neutralized and even converted into positive values. The gel to liquid crystalline phase transitions of LPS and lipid A shift to higher temperatures indicative of a rigidification of the acyl chains, however, the only slight enhancement of the transition enthalpy indicates that the hydrophobic moiety is not strongly disturbed. The aggregate structure of lipid A is converted from a cubic into a multilamellar phase upon ENP binding, whereas the secondary structure of ENP does not change due to the interaction with LPS. ENP contains a hydrophobic binding site to which the dye 1‐anilino‐8‐sulfonic acid binds at a Kd of 19 µm, which is displaced by LPS. Because lipopolysaccharide‐binding protein (LBP) is not able to bind to LPS when ENP and LPS are preincubated, tight binding of ENP to LPS can be deduced with a Kd in the low nonomolar range. Importantly, ENP is able to incorporate by itself into target phospholipid liposomes, and is also able to mediate the intercalation of LPS into the liposomes thus acting as a transport protein in a manner similar to LBP. Thus, LPS–ENP complexes might enter target membranes of immunocompetent cells, but are not able to activate due to the ability of ENP to change LPS aggregates from an active into an inactive form.
Laparoscopic radical prostatectomy: an audit after 2 years
Authors: CHAN S.W.H. , YUNG M.Y.P. , AU W.H. , MAH I.S.F. , MAN C.W.
Published: April 2004

Introduction: Laparoscopic radical prostatectomy (LRP) was first attempted in 1992. It was not until 1998 that this technique was recognized as an feasible alternative to traditional open surgery. Laparoscopy offers good visualization, magnification and allows precise dissection and intracorporeal suturing. An audit on the clinical outcomes was done on this novel technique.

Patients and Methods: 28 patients underwent LRP from March 2002 to February 2004. Inclusion criteria for surgery were similar to conventional open surgery's criteria: patients with high chance for organ‐confined disease and life expectancy of more than 10 years were included. Earlier series of open retropubic radical prostatectomy in the same hospital was used as the audit's standard for comparison.

Results: Favourable results over the open series were found with regard to catheter time, transfusion, hospital stay and later functional outcomes including continence and erectile function. Complications and oncological control was found to be similar for the two groups. Operative time was observed to have reduced from 480 min to less 200 min in the 28‐case series for the laparoscopic cases.

Conclusion Early results suggested favourable outcomes, but longer follow up and a controlled comparative study is needed to justify any definite conclusion for this relatively novel technique.
Clinico‐pathologic prediction of malignancy of thyroid follicular lesion with FNAC‐A multivariate analysis
Authors: CHOW T.L. , IP D.S.F. , CHAN T.T.F. , LAM S.H.
Published: April 2004

Background: Patients suffering thyroid nodules with the diagnosis of follicular lesion on FNAC normally undergo thyroidectomy as the diagnosis of follicular carcinoma can only be ascertained by histopatholoigc examination. We undertake this study to examine the likelihood of various preoperative clinicopathologic parameters to predict malignancy.

Methods: All the patients presented with thyroid nodules with follicular lesion diagnosed by FNAC were retrospectively evaluated if they have undergone thyroidectomy. The final histopathologic diagnoses were the gold standard. The clincopathologic parameters studied encompassed: gender, age, previous thyroidectomy, enlarging nodule, nodule size, presence of symptom, incidental finding, presentation duration, presence of Hurthle cell, cytological atypia and colloid content. The statistical analysis was carried out by SSPS 11.0 software. P‐value <*Τ*0.05 was considered statistically significant.

Results: A total of 354 thyroidectomies have been carried out from January 1998 to December 2003. Sixty‐seven patients satisfied the inclusion criteria. The mean age was 51.3 ± 15.4 years old. There were only eight male patients. The final histopathologic results were: hyperplastic nodule (n = 32), follicular or Hurthle cell adenoma (n = 22), follicular carcinoma (n = 3), Hurthle cell carcinoma (n = 3), papillary carcinoma (n = 4), medullary carcinoma (n = 1) and two cases of Hashimotos thyroiditis. On univariate analysis, nodule enlargement and cytological atypia were found to be significant predictors of malignancy. (Table) However, only the nodule enlargement remained significant on multivariate analysis. (P=0.048)

Sex (M vs F)
NS

Age (<50 vs >/50 year)
NS

Previous thyroid surgery (Yes vs No)
NS

Enlarging nodule (Yes vs No)
P=0.024

Nodule size (<3 vs >/=3 cm)
NS

Symptoms (Yes vs No)
NS

Incidental finding (Yes vs No)
NS

Presentation duration (<2 vs >/=2 year)
NS

Hurthle cell (Yes vs No)
NS

Cytological atypia (Yes vs No)
P=0.046

Colloid content (Yes vs scanty/nil)
NS

Conclusion: Enlargement of thyroid nodules with follicular lesion diagnosed by FNAC significantly associate with malignancy. This category of patients should receive early thyroidectomy.
Maximal host tolerance to large‐volume hepatic radiofrequency ablation in a rat model
Authors: NG K.K.C. , LAM C.M. , POON R.T.P. , SHEK T.W.H. , FAN S.T.
Published: April 2004

This is an in vivo study on normal and cirrhotic Sprague‐Dawlay rats to investigate the possible systemic responses of large‐volume hepatic radiofrequency ablation and to estimate its maximal host tolerance. Cool‐tip® RF System was used to ablate different percentage of liver volume in normal and cirrhotic rats. Systemic responses in terms of systemic inflammatory marker changes and end‐organ functions were determined. For the normal liver groups, the concentrations of systemic inflammatory markers were significantly elevated in early postoperative period when 50 and 60% of the liver volume were ablated, compared with the control group. Derangement of coagulation profile and interstitial penumonitis occurred after 50 and 60% of the liver volume were ablated. The survival rate was 100%, 60% and 0% when 40%, 50% and 60% of liver volume were ablated, respectively. Similar systemic responses were observed among the cirrhotic liver groups when 30 and 40% of the liver volume were ablated. The survival rate was 100%, 40% and 0% when 20%, 30% and 40% of the cirrhotic liver were ablated, respectively. The normal rats can tolerate hepatic RFA procedure maximally when 40% of the liver volume is ablated, whereas the cirrhotic rats can only tolerate RFA of 20% of the liver volume.
Endoscopic microvascular surgery: will it revolutionise the traditional microvascular surgery?
Authors: PANG P.C.W. , LAM S.C.K. , CHIU T. , BURD A.
Published: April 2004

Microvascular surgery has revolutionized the modern plastic surgery. It enables digit replantation. It has markedly increased the versality of pedicle flap by turning them into free flaps. The reliability of free flap in various conditions has approached 95%. Laparoscopic cholecystectomy was first performed in 1988. Though the lack of 3‐D and tactile sensation were the major obstacles in laparoscopic surgery, it has become a standard approach for a number of operations such as cholecystectomy, hernia repair, single stitch repair of perforated peptic ulcer. This paper is to study the feasibility, efficacy and difficulty encountered with endoscopic assisted microvascular surgery. Two plastic higher surgical trainees with some traditional microanastomosis experience and two plastic surgery specialists who are independently operating on microanastomosis were recruited. Each candidate performs end to end anastomosis of the aorta of 10 SD male rats (weighting 350–400 g) under microscope and 10 rats under endoscope. The rate of patent anastomosis (1 h after anastomosis), time taken for each anastomosis and difficulties were recorded. The feasibility and difficulty in the use of endoscope in performing microvascular anastomosis was evaluated. With devised instruments, microvascular anastomosis can be performed within a true intracorporal optical space.
Treatment of Ruptured Anterior Communicating Artery Aneurysm: Outcome and cost analysis of the combined microsurgical and endovascular team approach
Authors: WONG G.K. , BOET R. , YU S.C. , LAM J.M. , POON W.S.
Published: April 2004

Introduction: The practice model of case‐by‐case evaluation by a combined microsurgical and endovascular team based on the individual characteristics of each ruptured intracranial aneurysms, is the model used in most neurovascular centres in the US and in our centre. We aim to audit the outcome and cost (in terms of intensive care unit stay and hospital stay) in the microsurgical treatment group and endovascular treatment group.

Methods: The records of patients having ruptured anterior communicating artery aneurysm admitted to our unit between 1996 and 2002 were reviewed. A total of 54 patients were reviewed. Twenty‐seven patients had endovascular treatment and 27 patients had microsurgical treatment.

Results: The profiles for age, sex and admitting WFNS grading and Fisher grading were similar between the endovascular treatment and microsurgical treatment groups. Two patients in the endovascular group and one patient in the microsurgical group need further treatment for recurrent aneurysm. The mean intensive care unit stay is 7 days for the microsurgical group and 5 days for the endovascular group (P=0.40). The mean hospital ward stay is 20 days for the microsurgical group and 27 days for endovascular group (P=0.31). Favourable outcome was achieved in 70% of patients in 1 year in both groups of patients.

Conclusion: The outcome in both microsurgical and endovascular groups is satisfactory. There is no difference in terms of outcome and cost analysis between the two groups. The practice model of case‐by‐case evaluation by a combined microsurgical and endovascular team based on the individual characteristics of each ruptured intracranial aneurysm should be continued.
Physical, mental and social factors affecting self‐rated verbal communication among elderly individuals
Authors: Miura Hiroko , Kariyasu Makoto , Yamasaki Kiyoko , Sumi Yasunori
Published: April 2004

Background:  Satisfactory verbal communication is necessary to improve the quality of life in elderly individuals. However, few studies have directly analyzed the factors that influence the ability to achieve satisfactory verbal communication. The purpose of the present study was to identify the physical, mental and social factors that affect self‐rated verbal communication.

Methods:  A cross‐sectional survey was used to obtain the required data from 197 elderly (75.5 ± 8.3 years of age) individuals in the southern area of Japan who independently carried out basic activities of daily living. Subjective evaluation on verbal communication, general health status, oral function and hearing ability were assessed using a self‐administered questionnaire. Age, sex, instrumental activities of daily living, intellectual activity, social activity, cognitive status, the number of present teeth, maximum phonetic time and status regarding the use of dentures and hearing aids were also evaluated.

Results:  In bivariate analyses, self‐rated verbal communication ability was significantly related to age, instrumental activities of daily living, intellectual activity, social activity, cognitive function, maximum phonation time, the number of present teeth, the wearing of dentures, self‐rated general health and oral function. However, self‐rated hearing ability and the wearing of hearing aids were not significantly related to self‐rated verbal communication. The backward logistic regression analysis was refined until it included only two independent variables: social activity and self‐rated general health status.

Conclusion:  These results suggest that social activity and self‐rated general health status are the most influential factors of satisfactory verbal communication in the present model, and that self‐rated verbal communication is not related to hearing factors.
G‐substrate gene promoter SNP (−1323T>C) modifies plasma total cholesterol and triglyceride phenotype in familial hypercholesterolemia: Intra‐familial association study in an eight‐generation hyperlipidemic kindred
Authors: Nobe Yukiko , Sato Keiko , Emi Mitsuru , Ezura Yoichi , Fujita Yuko , Takada Daisuke , Ishigami Tomoaki , Umemura Satoshi , Xin Yunpei , Wu Lily L , Larrinaga‐Shum Stacey , Stephenson Susan H , Hunt Steven C , Hopkins Paul N
Published: April 2004

Background:  Plasma lipid and lipoprotein generally reflect the complex influences of multiple genetic loci, for instance, even familial hypercholesterolemia (FH), a representative example of monogenic hyperlipidemia, often presents with phenotypic heterogeneity.

Methods:  In the course of investigating familial coronary artery disease in Utah, we studied 160 members of an eight‐generation extended family of FH, to examine possible genetic modification of lipoprotein phenotype by ‘modifier locus’. G‐substrate (GSBS) is an endogenous substrate for cGMP‐dependent protein kinase. We carried out an intrafamilial correlation analysis of modifier effect of −1323T>C substitution in the GSBS gene among 85 LDLR‐mutation carriers and 75 non‐carriers.

Results:  In the LDLR‐mutation carriers, the plasma cholesterol levels were highest among −1323C homozygotes (mean ± SD = 454 ± 101 mg/dL), lowest among −1323T homozygotes (mean ± SD, 307 ± 72 mg/dL) and intermediate among −1323T/C heterozygotes (mean ± SD, 314 ± 62 mg/dL; P = 0.015). Similarly, in the LDLR‐mutation carriers, the plasma triglyceride levels were highest among −1323C homozygotes (mean ± SD, 371 ± 381 mg/dL), lowest among −323T homozygotes (mean ± SD, 171 ± 94 mg/dL), and intermediate among −1323T/C heterozygotes (mean ± SD, 218 ± 130 mg/dL; P = 0.003). No such gene‐interactive effect was observed among non‐carriers of the LDLR‐mutation.

Conclusion:  These results indicate a significant modification of the phenotype of FH with defective LDLR allele, by GSBS‐1323C allele in the kindred studied.
Development of a new method for simple dietary education in elderly patients with diabetes mellitus*
Authors: Takahashi Mitsuko , Araki Atsushi , Ito Hideki
Published: April 2004

Background:  The objective of this study was to compare the effects of simple dietary education on food intake, nutritional components and glycemic control to those of conventional dietary education.

Methods:  A randomized control trial was used to investigate the effects of this type of education. We randomly allocated 30 new elderly diabetic outpatients and 38 outpatients who had been visiting our clinic for a long time to the simple education group and the conventional education group. At baseline and 3 months after either the simple or conventional education, we assessed food and nutrient intake for a week using a Yoshimura's food frequency questionnaire. The HbA1c levels of patients were measured at baseline, 3, 6, and 12 months after education.

Results:  We developed a new method for simple dietary education, including several dietary lessons. In new diabetic patients, simple and conventional nutritional courses reduced HbA1c to similar levels at 3, 6, and 12 months as well as intake of total energy, sweets, and fruits at 3 months after the education. However, long‐term patients had no significant differences in total energy intake and HbA1c levels at 3 months, but at 6 and 12 months small decreases in HbA1c levels were observed for both the simple and conventional dietary education courses.

Conclusions:  Our results suggest that simple dietary education is useful and effective for elderly diabetic patients on their first visit in a similar fashion to the conventional dietary education. Because of the small effects of both types of education on glucose control in the long‐term patients, more psychosocial support may be necessary.
Factors related to functional capacity in community‐dwelling elderly
Authors: Kawamoto Ryuichi , Yoshida Osamu , Oka Yuichiro
Published: April 2004

Background:  The objectives of this study were to clarify the relationship between functional capacity and background factors in community‐dwelling elderly people.

Methods:  Study subjects were 1070 community‐dwelling persons aged 65 and older in 2001 who could provide complete responses to questionnaires regarding functional capacity. All subjects were enrolled from the April 2001 resident registry of Nomura‐cho in Ehime prefecture. Functional capacity was measured using the 13 items of the Tokyo Metropolitan Institute of Gerontology (TMIG) index for competence (instrumental self‐maintenance, intellectual activity, social role).

Results:  Subjects consisted of 472 men (mean age ± standard deviation, 73 ± 6.5 years) and 598 women (75 ± 7.6 years). Functional capacity decreased with age. In particular, functional capacity was markedly decreased in women at highly advanced ages. Multiple logistic regression analysis of functional capacity showed that significantly independent explanatory variables included younger age, good financial condition, participation in community activities, regular physical exercise, absence of prescription medication, absence of hearing impairment, absence of cognitive impairment and physical independence.

Conclusion:  These results indicate that good financial condition, participation in community activities, regular physical exercise, absence of prescription medication, absence of hearing impairment, absence of cognitive impairment and physical independence are important for maintaining functional capacity in elderly people. Early preventive measures are necessary to combat decline in functional capacity, particularly in women at highly advanced ages.
Nitric oxide synthase expression is increased by occlusal force in rat periodontal ligament
Authors: Warita H , Watarai H , Soma K
Published: April 2004

Structured Abstract

Authors – Warita H, Watarai H, Soma K

Objectives – The goal of this study was to investigate the role of nitric oxide synthase (NOS) in occlusal force‐induced signal transduction in rat periodontal ligament (PDL).

Design – Rats were fitted with a bite plate and a metal cap to the maxillary and mandibular incisors, respectively, to eliminate the occlusal forces on rat molars. One group was sacrificed at 7 days (exclusion group), while the remaining rats had their appliances removed to reestablish molar occlusal contact (reload group) and were sacrificed 7 days thereafter. Another group of rats (normal group) were left completely untreated. Frozen cross sections of the upper first molars were stained with NADPH‐diaphorase to quantify NOS activity. The distal sides of the disto‐palatal roots of the upper first molars were examined, and the number and the area of stained cells in the PDL were measured.

Results – In the normal group, NOS expression was detected in blood vessels, monocyte‐macrophages, fibroblastic cells and osteoclastic cells. NOS expression was lower in the exclusion group when compared with the normal group or the reload group (p < 0.05), and the exclusion group exhibited occluded blood vessels and a narrowing of PDL. In contrast, in the reload group the PDL and blood vessel structure had recovered and NOS expression was increased to the level of the controls.

Conclusion – Occlusal force resulted in increased NOS expression. NO may mediate changes in PDL structure in response to occlusal force.
Meta analysis of the treatment‐related factors of external apical root resorption
Authors: Segal GR , Schiffman PH , Tuncay OC
Published: April 2004

Structured Abstract

Authors – Segal GR, Schiffman PH, Tuncay OC

Objective – To elucidate possible treatment‐related etiological factors – such as, duration of treatment and apical displacement – for external root resorption.

Design – Meta‐analysis of the available English‐language literature.

Inclusion & Exclusion Criteria – Papers with a sample size >10, fixed appliances, pre‐ and post‐operative radiographs, and apical displacement recorded were included. History of trauma, prior root resorption and endodontic treatment were excluded. Appropriateness of these selections was tested with a ‘funnel plot’ analysis.

Outcome Measure – Correlations between root resorption, apical displacement, and treatment duration.

Results – Mean apical root resorption was strongly correlated with total apical displacement (r = 0.822) and treatment duration (r = 0.852).

Conclusion – The treatment‐related causes of root resorption appear to be the total distance the apex had moved and the time it took.
Natural Convection and Passive Heat Rejection from Two Heat Sources Maintained at Different Temperatures on a Printed Circuit Board
Authors: Weinstein Randy D. , Fleischer Amy S. , Krug Kimberly A.
Published: April 2004

Natural convection and passive heat rejection from two independent heat sources maintained at different temperatures (60°C and 100°C above ambient) on single circuit boards (FR4 and copper clad FR4) are experimentally studied. The effect of heat source location on maximum power dissipation is presented for both horizontal and vertical orientations. Heat losses due to radiation, natural convection and board conduction are quantified. As long as the heat sources are more than 2 cm apart, they do not influence each other on the FR4 board. Vertical orientation increases the power dissipation in the components by up to 30% for the FR4 board and 15% for the copper clad board. Two ounces of copper cladding increases the overall power dissipation by 150–190%.
A Hybrid Thermal Energy Storage Device, Part 2: Thermal Performance Figures of Merit
Authors: Zheng Ning , Wirtz R. A.
Published: April 2004

Two figures of merit for hybrid Thermal Energy Storage (TES) units are developed: the volumetric figure of merit, V˜, and the temperature control figure of merit, ΔT˜. A dimensional analysis shows that these quantities are related to the performance specification of the storage unit and its physical design. A previously benchmarked semi-empirical finite volume model is used to study the characteristics of various plate-type TES-unit designs. A parametric study is used to create a database of optimal designs, which is then used to form simple correlations of V˜ and ΔT˜ in terms of design requirements and attributes. A preliminary design procedure utilizing these figures of merit is suggested. Sample calculations show that these correlations can be used to quickly determine the design attributes of a plate-type TES-unit, given design requirements.
Simulative Analysis on Factors Influencing Solder Joint Bridging of Fine Pitch Devices
Authors: Yu Li Ming , Sur Bang Han , Pyo Kim Young , Qing Wang Chun , Lei Zhang
Published: April 2004

Solder bridging is one of the most serious defects of solder joint in fine pitch device assemblies. It is known that the generation of solder bridging is closely related to the forming process of solder joints. To simulate the process, a 3D model is formed. Then it is numerically simulated using Surface Evolver program. Based on the results, the solder bridging mechanism and the effective factors including wetting angle and surface tension are investigated.
CAPP for Electronics Manufacturing Case Study: Fine Pitch SMT Laser Soldering
Authors: Fidan Ismail
Published: April 2004

The trend to high-density packaging in surface mount assembly has highlighted inherent difficulties in the assembly line of these very fine pitch devices. A variety of defects is still common in printed circuit board assembly (PCBA) technology despite all the improvements made, and rework of PCBA is inevitable and performed manually in PCBA manufacturing floors since the cost of each component and PCB itself may be hundreds of dollars. In the last few years, the number of rework stations available on the market has grown considerably including the automated ones, but there has still been no significant reduction in the number of the defects. In electronics manufacturing, rework is defined as the activity that replaces defective components with those that are acceptable such that the populated board performs to the specifications. Increasing product complexity, decreasing component size, and using double sided boards have made rework more difficult and the economic reworking of PCBAs is one of the main problems facing PCB manufacturers. PCBA manufacturing has been relatively improved with fully automated, accurate assembly machines and the use of robots. Although significant improvement in automated rework has also been made by the author, it has been shown that the outcomes of the automated rework line have not produced a high enough level of the reliable yield percentage. The objective of this research project is to make a contribution towards this surface mount rework by creating a Computer Aided Process Planning (CAPP) system of circuit board defects so that the defects that necessitate rework operation can be detected through the electronics manufacturing assembly line. With the development of CAPP tool, the rework will be removed from the PCBA line and PCBA process parameters which cause joint level reliability problems will be troubleshot with the help of the developed system.
Investigation of Flip-Chip Bonding for MEMS Applications
Authors: Salalha W. , Zussman E. , Bar-Yoseph P. Z.
Published: April 2004

An investigation of the flip-chip bonding process for application in MEMS devices was carried out. Finite element analyses of axisymmetric and non-axisymmetric solder joint geometries were performed. It was found that in typical cases of MEMS devices in which the solder volume is small (Bo≪1, where Bo is the Bond number), the finite element solution of the axisymmetric solder joint is well approximated by a surface of revolution whose generating meridian is a circular arc. Experimental results of solder joints in flip-chip assembly were found to correlate well with simulation results.
Effects of Wafer Thinning Condition on the Roughness, Morphology and Fracture Strength of Silicon Die
Authors: McLellan Neil , Fan Nelson , Liu Shilai , Lau Kim , Wu Jingshen
Published: April 2004

A systematic investigation on the effects of wafer thinning process on the surface roughness, morphology and fracture strength of silicon chips was conducted. The results of the study suggest that the fracture strength of the silicon chips was determined predominantly by the geometry and scratch tip sharpness of a few large and deep scratches formed during wafer thinning. Although additional polishing by dry-polishing technique after traditional mechanical coarse/fine grinding could greatly improve the average roughness of the die surface, it would not further strengthen the silicon chips because the dry polishing could not successfully remove large scratches or reduce the scratch size. Plasma etching was found to have a high effectiveness in fracture strength improvement. Mechanism study shows that plasma etching turned the very sharp and large scratches into U-grooves, leading to a reduced stress concentration, hence, a much improved fracture strength.
Stacked Microchannel Heat Sinks for Liquid Cooling of Microelectronic Components
Authors: Wei Xiaojin , Joshi Yogendra
Published: April 2004

A novel heat sink based on a multilayer stack of liquid cooled microchannels is investigated. For a given pumping power and heat removal capability for the heat sink, the flow rate across a stack of microchannels is lower compared to a single layer of microchannels. Numerical simulations using a computationally efficient multigrid method [1] were carried out to investigate the detailed conjugate transport within the heat sink. The effects of the microchannel aspect ratio and total number of layers on thermal performance were studied for water as coolant. A heat sink of base area 10 mm by 10 mm with a height in the range 1.8 to 4.5 mm (2–5 layers) was considered with water flow rate in the range 0.83×10−6m3/s (50 ml/min) to 6.67×10−6m3/s (400 ml/min). The results of the computational simulations were also compared with a simplified thermal resistance network analysis.
Design of Cast Pin Fin Coldwalls for Air-Cooled Electronics Systems
Authors: Short, B. Elliott , Price Donald C. , Raad Peter E.
Published: April 2004

At low to moderate Reynolds numbers, cast pin fin coldwalls provide the best performance and lowest unit cost for air-cooled electronics systems. Until recently, insufficient data existed to design coldwalls with moderate length pin fins for electronics systems. Empirical correlations for the Fanning friction factor, f=fS/d,T/d,L/d,Red, and the Colburn j-factor, j=jS/d,T/d,L/d,Red, were previously developed for two flow regimes with a transition Reynolds number, Retrn, separating the two regimes. Using these correlations, the effect of configuration on the design is discussed and a design procedure is proposed. Example problems are presented for (1) a system cooled by an environmental control system, and (2) a system cooled by ambient air using a fan.