bluuebunny/crossref_metadata_2025 huggingface dataset:
Interface evolution and penetration behavior during two‐component transfer molding. Part II: Simulation and experiment
Authors: Li C. T. , Isayev A. I. , Warley R.
Published: May 2004

Simulation and experimental study of the pressure‐controlled sequential sandwich transfer molding of two SBR rubber compounds under isothermal condition have been carried out to obtain a two‐layered sandwich structure. One SBR compound, which is intended for the skin material, is first laid up in the cavity. Then, another SBR compound, intended for the core material, is transferred to penetrate into the skin material and to push the lay‐up to fully fill the cavity, resulting in an encapsulated skin/core sandwich structure. Two cases involving different material combinations with different viscosity ratios have been studied. The rheological interaction of the skin/core components and its effect on the penetration behavior and interface shape have been investigated. The influence of processing conditions, such as the volume fraction transferred and pressure, is discussed. The penetration and encapsulation behavior, and the interface development are found to be significantly affected by the rheological properties of the compounds and the volume fraction transferred. However, at a constant volume fraction transferred, the pressure imposed during transfer molding is found to have a little effect on the interface development. These experimental findings are in good agreement with the present predictions based on the model and simulation proposed in Part I of this study. Polym. Eng. Sci. 44:697–713, 2004. © 2004 Society of Plastics Engineers.
Simulation and experimental study of microwave heating of single lap adhesive‐bonded polypropylene joint
Authors: So H. W. , Taube A.
Published: May 2004

Microwave heating of modeled single lap adhesive‐bonded polypropylene joint was simulated using a computer program. The modeled joint was heated in an applicator based on a standard rectangular waveguide WR340 operating at 2.45 GHz with TE10 mode. The heating process was represented by a 2‐dimensional numerical model developed previously by the authors. The temperature distribution in the adhesive layer and the heating rate of the joint were predicted. The simulated results were validated by experiments. It was found that the simulation gave reasonably accurate prediction of the microwave heating of an adhesive joint. Polym. Eng. Sci. 44:728–735, 2004. © 2004 Society of Plastics Engineers.
Effect of composition on the solution rheology of stearyl methacrylate‐co‐styrene‐co‐vinyl pyrrolidinone in paraffinic base oil
Authors: Torres Edgar , Dutta Naba , Choudhury Namita Roy , Matisons Janis
Published: May 2004

The rheological behavior of dilute and semi‐dilute solutions of stearyl methacrylate‐co‐styrene‐co‐vinyl pyrrolidinone copolymers (SMA‐S‐VP) was investigated over a wide range of temperatures (20–140°C) under steady shear (0.1–5000 s−1) and dynamic conditions (0.01–500 rad/s). The solvent used was polyalpha olefin, PAO4 (C20‐C40 fraction), a fully synthetic paraffinic oil normally used as base oil for lubricant oil formulations. The investigation focuses on the effect of the polar comonomer segment content, of the copolymer, on the viscosity‐temperature relationship of the solution. This information provides insight into the effect of polymer microstructure on the viscosity index (VI) behavior of the lubricant. Copolymers with different ratios of stearyl methacrylate, styrene and vinyl pyrrolidinone were synthesized by solution radical polymerization. The microstructure and molecular weight of the copolymers were evaluated by nuclear magnetic resonance spectroscopy (NMR). The molecular weight and polydispersity of the polymers were determined using GPC. The polymer solutions exhibit non‐Newtonian behavior, which is more evident at lower temperatures and higher concentrations. The temperature‐concentration superposition principle developed by Ferry (1) was applied to steady shear data and the resulting master curve was fitted to the Carreau model. A modified Fedors equation for intrinsic viscosity calculation, at low and moderate polymer solution concentrations, was used. The results confirm that the viscosity index improver properties (VII) of the copolymer are superior when the VP content is low. The polymer‐solvent interactions and solvency power of PAO4 were analyzed using an Arrhenius expression. The results show that at low VP content, PAO4 is a better solvent for the copolymer. Polym. Eng. Sci. 44:736–748, 2004. © 2004 Society of Plastics Engineers.
Vibration welding of nylon 6 to nylon 66
Authors: Bates P. J. , Dyck C. , Osti M.
Published: May 2004

Vibration welding of dissimilar nylons is a promising technique for assembling complex components made of different polymers. The effects of pressure and meltdown on the tensile strength of nylon 6 (PA 6) to nylon 66 (PA 66) vibration welds were determined in this study using an experimental design and three weld geometries. Weld strengths were generally improved by increasing meltdown and decreasing weld pressure. The weld strength was also shown to vary with the position of the lower melting material for T‐welds. Using differential scanning calorimentry and fracture surface analyses, it is concluded that for all geometries, higher weld strengths can be achieved when both materials are melted. Polym. Eng. Sci. 44:760–771, 2004. © 2004 Society of Plastics Engineers.
Study of particle trajectories, residence times and flow behavior in kneading discs of intermeshing co‐rotating twin‐screw extruders
Authors: Bravo V. L. , Hrymak A. N. , Wright J. D.
Published: May 2004

A three‐dimensional finite element model was implemented for the solution of mass and momentum conservation equations in the kneading disc section of an intermeshing co‐rotating twin‐screw extruder. The polymer melt was modeled with a Carreau constitutive equation. The particle tracking technique was used to obtain residence times and analyze distributive mixing for different length to diameter ratios (L/D) of kneading discs. Previous studies from Kalyon et al. (1) and Cheng and Manas‐Zloczower (2) have shown that the mixing performance of intermeshing co‐rotating twin‐screw extruders is highly dependent on the combination of screw configuration and operating conditions. The complexity of the geometry and the transient character of the flow demand powerful computational tools to characterize the flow and to develop a prediction tool for the analysis of relative performance between different configurations. Difficulties arise in the particle tracking technique because of the time discretization and the presence of moving boundaries. Results show the importance of particle history on the evaluation of the relative performance of different configurations of kneading blocks and suggest a reevaluation of the use of average flow characteristics for the analysis of mixing. Results also confirm the importance of an accurate description of the geometry and clearances in order to obtain information about relative mixing performance. Polym. Eng. Sci. 44:779–793, 2004. © 2004 Society of Plastics Engineers.
Improved properties of blends of ultrasonically treated unfilled polyurethane rubber
Authors: Ghose Sayata , Isayev A. I.
Published: May 2004

The aim of this investigation is to improve the properties of the polyurethane rubber that has been devulcanized using the coaxial ultrasonic reactor. After devulcanization of the cured rubber under varying gap sizes and amplitudes, blends of the devulcanized and virgin rubber at different ratios are prepared. Rheological and mechanical properties, hardness as well as gel fraction and crosslink density of the vulcanized blends have been investigated. Results show that compared to the vulcanizates of the devulcanized samples, the vulcanizates of the blends show a remarkable improvement in properties, which are sometimes comparable to or even better than the virgin vulcanizate. Blends have also prepared using different proportions of ground samples and virgin rubber, and a comparison of properties between these blends and the blends of the devulcanized rubber has been carried out. The results show that compared to the ground samples, the blends of the devulcanized samples are easier to mix and exhibit enhanced and more uniform properties. Polym. Eng. Sci. 44:794–804, 2004. © 2004 Society of Plastics Engineers.
Patterns of self‐regulation and the Big Five
Authors: Gramzow Richard H. , Sedikides Constantine , Panter A. T. , Sathy Viji , Harris Joshua , Insko Chester A.
Published: May 2004

The authors examined relations between self‐regulatory properties of personality (ego‐control and ego‐resilience) and the Big Five. Ego‐control and ego‐resilience were independent predictors of each Big Five dimension. Additionally, cluster analysis suggested four replicable ‘types’. Participants in the first (largest) cluster reported the highest levels of resilience and moderately low levels of control. The second cluster reported above‐average resilience and high control. The third cluster reported below‐average resilience and extremely low control. The final cluster reported very low resilience and high control. The four clusters differed systematically in their Big Five profiles. These findings suggest that self‐regulatory processes are co‐ordinated with other basic personality dimensions, and attest to the utility of conducting both variable‐centred and person‐centred analyses. Copyright © 2004 John Wiley & Sons, Ltd.
Compliance and personality: the vulnerability of the unstable introvert
Authors: Gudjonsson Gisli H. , Sigurdsson Jon Fridrik , Bragason Olafur O. , Einarsson Emil , Valdimarsdottir Eva B.
Published: May 2004

The aim of the study was to assess the relationship of compliance with Eysenck's three personality dimensions: psychoticism, extraversion, and neuroticism. Three groups of participants (prison inmates, college students, and university students) completed the Gudjonsson Compliance Scale (GCS) and the Eysenck Personality Questionnaire (EPQ). As predicted, compliance correlated positively with neuroticism and negatively with extraversion in all groups, whereas for psychoticism the correlation was positive among the prison inmates, negative for college students, and non‐significant for university students. A quadrant analysis according to Eysenck's original two‐dimensional framework (neuroticism–stability and introversion–extraversion) showed that compliance was highest among unstable introverts and lowest among stable extraverts. The findings are discussed in relation to recent work on person‐type approaches. Copyright © 2004 John Wiley & Sons, Ltd.
Equilibrium adsorption model of anions onto a novel synthesized chelating fiber under various pHs and Fourier transform infrared study of these adsorptions
Authors: Ko Young Gun , Choi Ung Su , Woo Je Wan , Park Yong Sung
Published: May 2004

In this article, we present a new adsorption model of anion particles onto a chelating fiber. Nonideal H+ adsorption on the chelating fiber can be described adequately by the use of the heterogeneity factor β and the parameter Φ indicates the geometric factor of effective concentration in this model. The best fits of amines adsorption data were obtained by means of the developed model using two factors. Poly(acrylo‐amidino diethylene diamine) was synthesized as a chelating polymer through the coupling of diethylene triamine with polyacrylonitrile fiber in the presence of AlCl3 · 6H2O addition. Chromate ion and phosphate ion adsorption data on the synthesized poly(acrylo‐amidino diethylene diamine) were obtained. Fourier transform infrared studies of these adsorptions were also performed. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 2430–2440, 2004
Influence of conservation on calculations of amino acid covariance in multiple sequence alignments
Authors: Fodor Anthony A. , Aldrich Richard W.
Published: May 2004

It has long been argued that algorithms that find correlated mutations in multiple sequence alignments can be used to find structurally or functionally important residues in proteins. We examined the properties of four different methods for detecting these correlated mutations. On both simple, artificial alignments and real alignments from the Pfam database, we found a surprising lack of agreement between the four correlated mutation methods. We argue that these differences are caused in part by differing sensitivities to background conservation. Correlated mutation algorithms can be envisioned as “filters” of background conservation with each algorithm searching for correlated mutations that occur at a different background conservation frequency. Proteins 2004. © 2004 Wiley‐Liss, Inc.
Change in protein flexibility upon complex formation: Analysis of Ras‐Raf using molecular dynamics and a molecular framework approach
Authors: Gohlke Holger , Kuhn Leslie A. , Case David A.
Published: May 2004

Changes in flexibility upon protein–protein complex formation of H‐Ras and the Ras‐binding domain of C‐Raf1 have been investigated using the molecular framework approach FIRST (Floppy Inclusion and Rigid Substructure Topology) and molecular dynamics simulations (MD) of in total ∼35 ns length. In a computational time of about one second, FIRST identifies flexible and rigid regions in a single, static three‐dimensional molecular framework, whose vertices represent protein atoms and whose edges represent covalent and non‐covalent (hydrogen bond and hydrophobic) constraints and fixed bond angles within the protein. The two methods show a very good agreement with respect to the identification of changes in flexibility in both binding partners on a local scale. This implies that flexibility can be successfully predicted by identifying which bonds limit motion within a molecule and how they are coupled. In particular, as identified by MD, the β‐sheet in Raf shows considerably more pronounced orientational correlations in the bound state compared to the unbound state. Similarly, FIRST assigns the β‐sheet to the largest rigid cluster of the complex. Interestingly, FIRST allows us to identify that interactions across the interface (but not conformational changes upon complex formation) result in the observed rigidification. Since regions of the β‐sheet of Raf that do not interact directly with Ras become rigidified, this also demonstrates the long‐range aspect to rigidity percolation. Possible implications of the change of flexibility of the Ras‐binding domain of Raf on the activation of Raf upon complex formation are discussed. Finally, the sensitivity of FIRST results with respect to the representation of non‐covalent interactions used as constraints is probed. Proteins 2004. © 2004 Wiley‐Liss, Inc.
Quantum descriptors for biological macromolecules from linear‐scaling electronic structure methods
Authors: Khandogin Jana , York Darrin M.
Published: May 2004

The characterization of electrostatic and chemical properties at the surface of biological macromolecules is of interest in elucidating the fundamental biological structure‐function relationships as well as in problems of rational drug design. This paper presents a set of macromolecular quantum descriptors for the characterization of biological macromolecules in solution that can be obtained with modest computational cost from linear‐scaling semi‐empirical quantum/solvation methods. The descriptors discussed include: solvent‐polarized electrostatic surface potential maps, equilibrated atomic charges, Fukui reactivity indices, approximate local hardness maps, and relative proton potentials. These properties are applied to study the conformational dependence of the electrostatic surface potential of the solvated phosphate‐binding protein mutant (T141D), the regioselectivity of the zinc finger domains of HIV‐1 nucleocapsid (NC) protein, and the order of pKa values of acidic residues in turkey ovomucoid third domain (OMTKY3) and of the zinc‐binding residues in the carboxyl terminal zinc finger of NC. In all cases, insight beyond that obtainable from purely classical models is gained and can be used to rationalize the experimental observations. The macromolecular quantum descriptors presented here greatly extend the arsenal of tools for macromolecular characterization and offer promise in applications to modern structure‐based drug design. Proteins 2004. © 2004 Wiley‐Liss, Inc.
Profile–profile methods provide improved fold‐recognition: A study of different profile–profile alignment methods
Authors: Ohlson Tomas , Wallner Björn , Elofsson Arne
Published: May 2004

To improve the detection of related proteins, it is often useful to include evolutionary information for both the query and target proteins. One method to include this information is by the use of profile–profile alignments, where a profile from the query protein is compared with the profiles from the target proteins. Profile–profile alignments can be implemented in several fundamentally different ways. The similarity between two positions can be calculated using a dot‐product, a probabilistic model, or an information theoretical measure. Here, we present a large‐scale comparison of different profile–profile alignment methods. We show that the profile–profile methods perform at least 30% better than standard sequence‐profile methods both in their ability to recognize superfamily‐related proteins and in the quality of the obtained alignments. Although the performance of all methods is quite similar, profile–profile methods that use a probabilistic scoring function have an advantage as they can create good alignments and show a good fold recognition capacity using the same gap‐penalties, while the other methods need to use different parameters to obtain comparable performances. Proteins 2004. © 2004 Wiley‐Liss, Inc.
A modified internal lock‐mass method for calibration of the product ions derived from sustained off‐resonance irradiation collision‐induced dissociation using a Fourier transform mass spectrometer
Authors: Duan Lifang , Chan T.‐W. Dominic
Published: May 2004

A modified internal lock‐mass calibration method is introduced for improving the mass measurement accuracy of the product ion spectra derived from sustained off‐resonance irradiation collision‐induced dissociation (SORI‐CID) Fourier transform ion cyclotron resonance (FTICR) mass spectrometry. This method involves an initial external calibration of the Fourier transform mass spectrometer to obtain the initial A‐ and B‐terms for the equation (fi = A/(m/z)i + B). The A‐term is adjusted by using an empirical relationship between the up‐shift of the A‐term and the pulse‐gas duration, whereas the B‐term is adjusted by using the mass of the unfragmented precursor ion from the SORI‐CID mass spectrum of the unknown sample as internal lock‐mass. These adjusted A‐ and B‐terms are then used to provide exact mass SORI‐CID calibration for the unknown sample. The modified internal lock‐mass method achieved average mass measurement accuracy of ∼3 ppm which is significantly better than that of the conventional internal lock‐mass calibration (∼9 ppm) and is approaching that of the internal calibration (∼2 ppm) and requires no addition of internal calibrant or instrumental modifications. Copyright © 2004 John Wiley & Sons, Ltd.
Electrospray ionization mass spectrometric analysis of nucleic acids using high‐throughput on‐line desalting
Authors: Fountain Kenneth J. , Gilar Martin , Gebler John C.
Published: May 2004

A rapid on‐line desalting method utilizing ion‐pair reversed‐phase high‐performance liquid chromatography (IP‐RP‐HPLC) was employed in tandem with negative electrospray ionization mass spectrometry (ESI‐MS) for the routine analysis of nucleic acids. Desalting was performed on a short 10 × 2.1 mm guard column packed with 3.5 μm C18 sorbent. The HPLC system was connected in‐line to an orthogonal ESI‐TOF mass spectrometer via a six‐port, two‐position switching valve, allowing desalting followed by mass analysis of nucleic acids. Duty cycle times for the method were as low as 1.5 min per sample. This allowed for the analysis of approximately 950 samples per 24‐h time period, which is suitable for medium‐ to high‐throughput applications. Average mass accuracy was determined to be 80 ppm for oligonucleotides up to 110 mer in length with external calibration. The method was utilized for synthetic oligonucleotide quality control and analysis of DNA genotyping fragments. Copyright © 2004 John Wiley & Sons, Ltd.
Fragmentation of biotinylated cyclic peptides
Authors: Lassman Michael E. , Kulagina Nadia , Taitt Chris Rowe
Published: May 2004

Electrospray ionization coupled with tandem mass spectrometry (MS/MS) was used to determine the preferred binding site(s) of biotin NHS ester with a series of cyclic peptides with antibiotic properties. The peptides investigated are polymyxins, cyclic peptides produced by Bacillus polymyxa. In spite of the 1:1 stoichiometry used in the labeling reaction, multiple biotin molecules were incorporated into intact polymyxin peptides. Given the amine specificity of the activated biotin and the large number of amino acids with primary amines in the polymyxins, it was not clear by inspection which binding sites were more reactive than others. MS/MS was used to characterize the structure of the biotinylated peptides. MS/MS spectra of cyclic peptides often lead to ambiguous structure determinations due to the potential for multiple ring openings which result in the generation of multiple ion series. The MS/MS spectra of polymyxin peptides are especially difficult to characterize due to the lack of variety in their amino acids; however, the added complexity of the biotin aided the elucidation of the fragmentation pathways. MS/MS spectra of the species with biotin additions were used to rationalize the preferential binding sites of these molecules. Published in 2004 by John Wiley & Sons, Ltd.
Varieties of pairs of nilpotent matrices annihilating each other
Authors: Schröer Jan
Published: May 2004

We classify the irreducible components of the varieties

\textup{V}(n,a,b) = \{ (A,B) \in \textup{M}_n(K) \times \textup{M}_n(K) \mid AB = BA = A^a = B^b = 0 \}.
The stable equivalence and cancellation problems
Authors: Makar-Limanov Leonid , van Rossum Peter , Shpilrain Vladimir , Yu Jie-Tai
Published: May 2004

Let K be an arbitrary field of characteristic 0, and

\mathbf{A}^n

the n-dimensional affine space over K. A well-known cancellation problem asks, given two algebraic varieties

V_1, V_2 \subseteq \mathbf{A}^n

with isomorphic cylinders

V_1 \times \mathbf{A}^1

and

V_2 \times \mathbf{A}^1

, whether

V_1

and

V_2

themselves are isomorphic. In this paper, we focus on a related problem: given two varieties with equivalent (under an automorphism of

\mathbf{A}^{n+1}

) cylinders

V_1 \times \mathbf{A}^1

and

V_2 \times \mathbf{A}^1

, are

V_1

and

V_2

equivalent under an automorphism of

\mathbf{A}^n

? We call this stable equivalence problem. We show that the answer is positive for any two curves

V_1, V_2 \subseteq \mathbf{A}^2

. For an arbitrary

n \ge 2

, we consider a special, arguably the most important, case of both problems, where one of the varieties is a hyperplane. We show that a positive solution of the stable equivalence problem in this case implies a positive solution of the cancellation problem.
The representation theory of cyclotomic Temperley-Lieb algebras
Authors: Rui Hebing , Xi Changchang
Published: May 2004

A class of associative algebras called cyclotomic Temperley-Lieb algebras is introduced in terms of generators and relations. They are closely related to the group algebras of complex reflection groups on the one hand and generalizations of the usual Temperley-Lieb algebras on the other hand. It is shown that the cyclotomic Temperley-Lieb algebras can be defined by means of labelled Temperley-Lieb diagrams and are cellular in the sense of Graham and Lehrer. One thus obtains not only a description of the irreducible representations, but also a criterion for their quasi-heredity in the sense of Cline, Parshall and Scott. The branching rule for cell modules and the determinants of Gram matrices for certain cell modules are calculated, they can be expressed in terms of generalized Tchebychev polynomials, which therefore play an important role for semisimplicity.
Integral bases for TQFT modules and unimodular representations of mapping class groups
Authors: Gilmer Patrick M. , Masbaum Gregor , van Wamelen Paul
Published: May 2004

We construct integral bases for the

SO(3)

-TQFT-modules of surfaces in genus one and two at roots of unity of prime order and show that the corresponding mapping class group representations preserve a unimodular Hermitian form over a ring of algebraic integers. For higher genus surfaces the Hermitian form sometimes must be non-unimodular. In one such case, genus three at a fifth root of unity, we still give an explicit basis.
Laparoscopic Cholecystectomy: Its Effect on the Prognosis of Patients with Gallbladder Cancer
Authors: de Aretxabala Xabier A. , Roa Ivan S. , Mora Javier P. , Orellana Juan J , Riedeman Juan P. , Burgos Luis A. , Silva Veronica P. , Cuadra Alvaro J. , Wanebo Harold J.
Published: May 2004

Numerous reports suggest more recurrences and a worse prognosis after laparoscopic cholecystectomy (LC) than after open cholecystectomy (OC). The objective of this study was to compare the survival rate of patients undergoing a laparoscopic procedure versus those undergoing an open operation. A series of 24 patients with gallbladder cancer detected after LC were compared with 40 consecutive patients with gallbladder cancer detected after OC. Patients were matched by wall invasion, age, and whether they underwent a reoperation or only cholecystectomy. The series included 2 patients with in situ tumors, 2 with mucosal tumors, 1 with muscular invasion, 13 with subserosal invasion, and 6 with serosal invasion. Recurrences were observed in 4 of the 10 patients with subserosal compromise who underwent reoperation. In contrast, in the OC group of 26 patients with subserosal invasion, 20 of whom were reoperated, only 2 had a recurrence. Of the six patients with serosal infiltration, three in the LC underwent reoperation, all of whom had recurrences that precluded resection. Of the 12 patients in the OC group who presented with serosal invasion, 6 were reoperated and 4 had a recurrence. Overall survival curves did not show differences when patients were compared according to the type of procedure performed. Similarly, the analysis of patients according to the level of wall invasion indicated that there was no significant difference in survival. Although multiple reports have shown a worse prognosis for patients with gallbladder cancer undergoing LC, this study did not show a significant survival difference between the two methods. Although there is a higher but insignificant recurrence rate among the patients who underwent LC, this is not translated into survival.
Usefulness of Radio‐guided Surgery Using Technetium‐99m Methoxyisobutylisonitrile for Primary and Secondary Hyperparathyroidism
Authors: Takeyama Hiroshi , Shioya Hisashi , Mori Yutaka , Ogi Shigeyuki , Yamamoto Hiroyasu , Kato Naohiko , Kinoshita Satoki , Yoshida Kazuhiko , Uchida Ken , Yamazaki Yoji
Published: May 2004

The efficacy of technetium‐99m methoxyisobutylisonitrile (99mTc‐MIBI)‐guided surgery for detecting abnormal parathyroid glands in patients with secondary hyperparathyroidism (2‐HPT) was evaluated and compared with the results from the same examination in patients with primary hyperparathyroidism (1‐HPT). The results were also compared with those found by ultrasonography (US) and preoperative 99mTc‐MIBI scintigraphy was also made. At operation 99mTc‐MIBI accumulated in 64 nodules of 15 cases of 2‐HPT, and all of 60 parathyroid swellings were detected (true‐positives 60, sensitivity 100%, accuracy 94%). In the cases of 1‐HPT, 99mTc‐MIBI revealed 11 hot nodules in 10 cases, and the evaluation was true‐positive 10, sensitivity 100%, and accuracy 91%. US and preoperative 99mTc‐MIBI scintigraphy in patients with 2‐HPT had a sensitivity of 75% and 67% and an accuracy of 70% and 66%, respectively. The usefulness of 99mTc‐MIBI‐guided surgery for detecting abnormal parathyroid tissue in 2‐HPT patients was similar to that in 1‐HPT patients but was superior to US and preoperative 99mTc‐MIBI scintigraphy. Intraoperative 9mTc‐MIBI for patients with 2‐HPT is effective and makes the surgery easier, especially when the parathyroid glands are ectopic or when a few glands are markedly enlarged but the other glands are atrophied.
Combined Assessment of β‐d‐Glucan and Degree of Candida Colonization before Starting Empiric Therapy for Candidiasis in Surgical Patients
Authors: Takesue Yoshio , Kakehashi Masayuki , Ohge Hiroki , Imamura Yuuji , Murakami Yoshiaki , Sasaki Masaru , Morifuji Masahiko , Yokoyama Yujiro , Kouyama Mohei , Yokoyama Takashi , Sueda Taijiro
Published: May 2004

The purpose of the study was to investigate whether examination for plasma β‐d‐glucan, a cell wall constituent of fungi, is useful for selecting surgical patients with Candida colonization who would benefit from empiric antifungal therapy. We administered fluconazole to postoperative patients with Candida colonization who have risk factors for candidemia and complained of persistent fever despite prolonged antibacterial therapy. We then analyzed the clinical outcomes regarding the number of sites colonized with Candida spp. and plasma β‐d‐glucan. Of the 32 patients positive for β‐d‐glucan, 15 (46.9%) responded to the empiric therapy; only 9% of those who were negative responded (p < 0.01). In the multiple logistic regression analysis, being positive for β‐d‐glucan was a significant factor predicting response, with an adjusted odds ratio of 12.9 in patients with Candida colonization [95% confidence interval (CI) 2.07–80.73) (p < 0.01). In addition, the number of sites colonized with Candida spp. was a significant factor predicting response, with an estimated exposure odds ratio of 7.57 for those who were colonized at three or more sites compared with those colonized at one site (95% CI 1.20–47.70) (p = 0.031). In patients with Candida colonization, assessment of β‐d‐glucan was useful for deciding whether to start empiric therapy for suspected candidiasis in surgical patients.
Assessing the Site of Recurrence in Patients with Secondary Hyperparathyroidism by a Simplified Casanova Autograftectomy Test
Authors: Schlosser Katja , Sitter Helmut , Rothmund Matthias , Zielke Andreas
Published: May 2004

Patients with recurrent secondary hyperparathyroidism (rSHPT) following total parathyroidectomy and autotransplantation were prospectively studied by a modified Casanova test to discriminate between the graft‐bearing arm and the neck as the site of the recurrence. The test measures intact parathyroid hormone (PTH) in blood obtained from the non‐graft‐bearing arm before an ischemic period and from the arm bearing the parathyroid graft during an ischemic period caused by an Esmarch bandage. The aim of this study was to evaluate the time course of PTH levels during the test and to establish an abbreviated procedure. A series of 30 patients with rSHPT who were admitted for reoperative surgery between 1994 and 2002 were studied. Systemic PTH levels were determined prior to suprasystolic exclusion of the graft‐bearing arm as well as 2, 4, 6, 8, 10, 20, and 30 minutes during it and at 10 minutes afterward. Results were interpreted with a simple algorithm that suggested graft‐dependent recurrence (GDR) whenever PTH levels dropped by more than 50% and neck‐dominated recurrence (NDR) whenever the PTH levels dropped to less than 20%. Patients were operated on accordingly. Biochemical normalization of calcium and PTH was defined as success. Altogether, 15 patients had GDR and were cured after graft explantation. All of these patients were identified within 4 minutes of starting the test. Another 12 patients had NDR and were cured by excising overlooked or supernumerary glands. PTH levels were indeterminate in three patients (10%). Clinically, NDR is likely in all of these cases, but the test results were firmly established with 100% accuracy 8 minutes after the start of the test procedure. This abbreviated form of the Casanova test is advantageous for accurately determining the site of recurrence in the presence of rSHPT. It is less time‐consuming, satisfactory in an ambulatory setting, equally effective, and less invasive than the original Casanova procedure.
Maternal deaths in the less developed world: preventable tragedies
Authors: Darney Philip D.
Published: May 2004

A half million women die yearly around the world as a result of pregnancy. Many of these deaths are inaccurately classified and many others are not reported at all, but new demographic techniques have clarified causes of maternal mortality and improved estimates of rates. New data from several less developed countries suggest that many maternal deaths could be prevented by measures already demonstrated to be effective elsewhere. These include better antenatal and intrapartum care, contraception for women who want no more pregnancies, legal abortion to terminate unwanted pregnancies, and uterine aspiration and antibiotics for treatment of septic abortion.
Preliminary report of an identification mission for safe motherhood, Senegal: putting the M back in M.C.H.
Authors: Kimball A.M. , Cisse S. , Fayemi G. , Ericcson S. , Helfenbein S. , Nakoulima A. , Sene N.T. , Papiernik E.
Published: May 2004

The Government of Senegal, in keeping with the priority given to women and children in its health programs, requested the assistance of the United Nations Development Program (UNDP) in identifying and executing a program to diminish maternal mortality in that country. A UNDP “Mission of Identifiation” was carried out in response to this initiative. The preliminary results of this mission confirm that the issue of maternal safety is of primary concern not only to the government but also to women in the Republic of Senegal. The methodology employed during this mission allowed the team of national and international experts to confirm the level of this concern and to identify four major potential areas of intervention. Quantitative goals for the program have been set and estimates for the efficacy of each of the intervention areas indicate that intervention through the timely provision of access to emergency surgical services and appropriate prenatal care will yield the largest reduction. The feasibility of providing interventions in each of the four areas was also addressed during the mission. This methodology will be applicable to other settings as Third World countries begin to address the problem of excessive maternal mortality.
Obstetric complications of macrosomic babies in African women
Authors: Megafu Uchenna , Ozumba B.C.
Published: May 2004

A prospective analysis has been made on 145 consecutive deliveries resulting in babies weighing 4.5 kg and above delivered at the University of Nigeria Teaching Hospital (U.N.T.H.), Enugu, over a 1‐year period (1985). Babies weighing 4.5 kg and over are regarded as macrosomic babies. The incidence of macrosomic babies in this study is 11 per thousand deliveries or 1 in 90. Factors that predisposed to the birth of macrosomic babies include: excessive weight gain during the course of pregnancy, tall height of the woman, multiparity and prolonged gestation. Diabetes mellitus was not a significant factor. Complications include prolonged labor, post‐partum hemorrhage, ruptured uterus, shoulder dystocia and an increased perinatal mortality rate. Maternal mortality was also increased. Ninety percent of the multiparous women achieved spontaneous vaginal delivery while only 42% of the primigravidae achieved vaginal delivery. The implications are discussed.
Induction of dead fetus labor with 15‐(S)‐methyl prostaglandin F2α
Authors: Miranda J.A. , Herruzo A.J. , Montoya F. , Huete A. , Mallol M.C. , Delaorden A.F.
Published: May 2004

This study examines whether labor can be induced with the intramuscular administration of 15‐(S)‐methyl prostaglandin F2α in cases of intrauterine fetal death. The success rate of labor induction in the studied group was 93.75%, and was the same for primigravid and multigravid patients. The authors conclude that the prophylactic administration of an analgesic potentiator, an anti‐emetic and an anti‐diarrheal is advantageous to a woman's tolerance of the prostaglandin. PGF2α is a quick and effective drug for use in the induction of labor to terminate pregnancies with intrauterine fetal death and offers tolerable side‐effects when used with adjuvant medication.
Fetal biparietal diameter and head circumference measurements: results of a longitudinal study in Zimbabwe
Authors: Munjanja S.P. , Masona D. , Masvikeni S.
Published: May 2004

In a longitudinal study in Harare, Zimbabwe, 1233 biparietal diameter and 857 head circumference measurements were obtained from the fetuses of 190 women. Weekly mean values and the two standard deviations were calculated for both the biparietal diameter and head circumference from 12 to 40 weeks of pregnancy. There was little difference between these values and some Caucasian and African standards. Comparison was also made of the weekly biparietal diameter growth rate between our results and those from one study in West Africa. The possible reasons for the differences are explained.
Evaluation of tolerance of and response to iron dextran (Imferon®) administered by total dose infusion to pregnant women with iron deficiency anemia
Authors: Kaisi M. , Ngwalle E.W.K. , Runyoro D.E. , Rogers J.
Published: May 2004

Six hundred twenty‐three pregnant women with iron deficiency anemia received iron dextran Imferon® by total dose infusion (TDI). Two dose levels were compared in respect of tolerance and hemoglobin response. The incidence of delayed reactions was significantly higher in the high dose group (P < 0.01) but there was no significant difference in the incidence of reactions occurring during the infusion. These findings are discussed in relation to the hemoglobin response.
Estrogen treatment and subsequent pregnancy in two patients with severe hypergonadotropic ovarian failure
Authors: Varma T.R. , Patel R.H.
Published: May 2004

The history, diagnosis and management of two patients with premature ovarian failure who responded to estrogen replacement therapy is presented. Both women conceived and had a live healthy baby.
Bacterial resistance in South America
Authors: Peixoto S.
Published: May 2004

The emergence of resistant strains of bacteria is directly related to the selection of chemotherapeutic agents, and the character of the resistance changes with changes in usefrequency of the various antibiotics. In recent years with increasing use of beta‐lactam antibiotics, there has been an increased incidence of microorganisms that are resistant by virtue of their ability to produce beta‐lactamase enzymes which destroy the beta‐lactam antibiotics. The development of beta‐lactamase inhibitors which may be used in combination with the beta‐lactam antibiotics has been a significant advance for the therapy of gynecologic infections in South America.
Sulbactam/ampicillin in the treatment of acute pelvic inflammatory disease
Authors: Sweet R.L. , Landers D.V. , Schachter J. , Crombleholme W.R.
Published: May 2004

Acute pelvic inflammatory disease is associated with significant adverse reproductive sequelae. To prevent these serious sequelae, treatment regimens must cover the major etiologic agents which are Neisseria gonorrhoeae, Chlamydia trachomatis, and mixed anaerobic‐aerobic bacteria. This report concerns the prospective evaluation of the efficacy of the combination of sulbactam with ampicillin in patients hospitalized with acute pelvic inflammatory disease. Clinical cure was noted in 33 (94%) of 35 patients and post‐treatment cultures demonstrated eradication of N. gonorrhoeae and C. trachomatis in all cases.
Sulbactam/ampicillin versus cefotetan in the treatment of obstetric and gynecologic infections
Authors: Scalambrino S. , Mangioni C. , Milani R. , Regallo M. , Norchi S. , Negri L. , Carrera S. , Vigano E.F. , Ruffilli M.P. , Canale M.P.
Published: May 2004

In an open, randomized clinical study, the safety and efficacy of sulbactam/ampicillin was compared to that of cefotetan in 95 hospital patients with gynecologic or obstetric infections. Sulbactam/ampicillin (1 g:2 g), was administered intravenously every 8 h to 46 patients, and cefotetan (2 g) was administered intravenously every 12 h to 49 patients. All 23 patients with obstetric infections and 18 of the 23 patients with gynecologic infections treated with sulbactam/ampicillin were evaluated as cured. All 21 patients with obstetric infections and 23 of the 28 patients with gynecologic infections treated with cefotetan were evaluated as cured. No side effects requiring discontinuation of therapy or reduction of the dose administered, were observed.
Perioperative systemic antibiotics for prophylaxis of infections in breast surgery: sulbactam/ampicillin versus mezlocillin/oxacillin
Authors: Engel K. , Wildfeuer A.
Published: May 2004

In a prospective, randomized, open trial, efficacy of one dose of sulbactam/ampicillin (1 g:2 g) was compared to three doses of mezlocillin/oxacillin (2 g:1 g), starting with induction of anesthesia in 80 breast surgery patients with an increased risk of postoperative infection. No infections at the site of operation were seen in either group. Fever due to postoperative pulmonary complications occurred in one patient in the sulbactam/ ampicillin group. The only side effect was a moderate exanthema observed in one patient in the mezlocillin/oxacillin group. In this study of the prophylaxis of patients with an increased risk of postoperative infections having the potential to jeopardize the results of surgery, a single dose of sulbactam/ampicillin was as effective as a short term course of three doses of mezlocillin/oxacillin.
Radionuclide hysterosalpingography for measurement of human oviductal function
Authors: Brundin Jan , Dahlborn M. , Ahlberg‐Ahre Eva , Lundberg H.J.
Published: May 2004

A clinical method is described and claimed to evaluate the active transportation capacity of the luminal epithelium lining the human uterus and fallopian tube. After intracervical application of technetium‐labelled human albumin spheres at 1–2 days before ovulation this radioactivity could be followed by gamma‐camera when moved in ad ovarian direction. This method is called radionuclide hysterosalpingography (RN‐HSG). The results were compared to the findings at normal hysterosalpingography (HSG). By use of this method it was possible to verify active passage in cases of tubal spasm at HSG, lack of transport in cases of normal patent oviducts at HSG as well as presence or absence of active transport through sactosalpinges with or without fimbrial passages to the abdominal cavity as seen at normal HSG. Congruent findings between HSG and RN‐HSG was observed in 49%. The studied oviducts were found to be patent with normal HSG but lacked transportation capacity when studied by RN‐HSG in 41%. The clinical use of this method is discussed in view of the selection of patients for different forms of in vitro fertilization and egg transfer (IVF‐ET).
Malignant ovarian tumors associated with pregnancy: Report of six cases
Authors: Matsuyama T. , Tsukamoto N. , Matsukuma K. , Kamura T. , Kaku T. , Saito T.
Published: May 2004

Six cases of pregnancy associated malignant ovarian tumors, four epithelial cancers, one immature teratoma and one metastatic cancer of colon origin, are reported. One patient with mucinous cystadenocarcinoma had a history of persistent ovarian tumor during her past three pregnancies. Another patient was found to have mucinous cystadenocarcinoma after an emergency operation for twisted ovarian tumor. Immature teratoma associated with pregnancy is very rare and our case seems to be the 8th reported such case.
Endometrial carcinoma presenting as a large inguinal mass
Authors: Ramahi A. , Malviya V.K. , Ataya K.M. , Deppe G.
Published: May 2004

Patients with endometrial cancer usually present with vaginal bleeding. A case of endometrial cancer presenting as an asymptomatic, large, inguinal mass is reported. This unusual clinical picture and its management are discussed.
Uterine sarcoma with liposarcomatous differentiation: Report of a case and review of the literature
Authors: Bapat K. , Brustein S.
Published: May 2004

Heterologous sarcomas of the uterus are uncommon neoplasms. A liposarcoma in combination with a leiomyosarcoma of the uterus has been reported only once prior to this case report. We report a case of uterine sarcoma demonstrating two distinct variants of liposarcoma. This has not been seen to date.
Postterm pregnancy: computer analysis of the antepartum fetal heart rate patterns
Authors: Bartnicki J. , Ratanasiri T. , Meyenburg M. , Saling E.
Published: May 2004

The purpose of this study was to establish reference ranges for numerical fetal heart rate (FHR) data in postterm pregnancy and to compare them with the patterns of fetuses under undisturbed condition at term. FHR was analysed on‐line by Sonicaid Computer System 8000. A statistically significant decrease in the number of accelerations and decrease of variation in postterm pregnancy was observed. The duration of high variation (high episodes) in the 42nd week of gestation was statistically lower than in the pregnancy at term. These observations should be taken into account by clinicians in the interpretation of FHR records in postterm pregnancy.
Methotrexate local injection for unruptured tubal pregnancy: an alternative to laparotomy?
Authors: Pansky M. , Bukovsky I. , Golan A. , Herman A. , Hertziano I. , Langer R. , Caspi E.
Published: May 2004

Fifty‐nine women with early unruptured tubal pregnancy were treated by a single local injection of methotrexate at laparoscopy. All 59 patients underwent the procedure without any adverse reaction, 47 (80%) of them needing no laparotomy. Twelve patients required a laparotomy for reasons such as rising β‐hCG levels and abdominal pain with or without rising levels of β‐hCG. Only one patient ruptured the tube. None of the women needed a blood transfusion. We found tubal patency in 19 out of 21 patients at follow up hysterosalp‐ingography. Eleven pregnancies were subsequently reported, one of them tubal. The appearance of the injected tube was absolutely normal in three patients, one at cesarean section and two at repeated laparoscopy. No peritubal adhesions were observed. We suggest that this new technique is a safe and effective alternative to laparotomy in a patient with an early unruptured tubal pregnancy.
Recurrent leiomyoma of the vagina
Authors: Dhaliwal L.K. , Das I. , Gopalan S.
Published: May 2004

A rare case of huge vaginal leiomyoma recurrence is reported. Vaginal leiomyoma is a rare entity and recurrence after its removal is extremely rare. However, if recurrence occurs with intact ovarian function ovariectomy should also be done.
Intravenous leiomyomatosis with massive ascites
Authors: Mullings A.M.A. , Char G. , Martin M.P. , Frederick J. , Walton N. , Pickering K.
Published: May 2004

A case of intravenous leiomyomatosis with massive ascites is reported. This is the first such recorded case. The patient was treated with a subtotal abdominal hysterectomy and bilateral salpingo‐oophorectomy. Pathological examination established a vessel wall origin. There is no evidence of recurrence up to 20 months after initial treatment.
Proximal tubal obstruction associated with tubal schistosomiasis
Authors: Letterie G.S. , Sakas L.
Published: May 2004

The gynecologic consequences of schistosomiasis may range from minimal inflammation of tubal serosa to more intense reactions involving the periadnexal regions. Complete obliteration of the tubai lumen has not been described. We describe a case of proximal tubal obstruction associated with tubal schistosomiasis.