bluuebunny/crossref_metadata_2025 huggingface dataset:
Relationship between Gough-Joule Coefficients and Moduli of Vulcanized Rubbers
Authors: Conant F. S. , Hall G. L. , Thurman G. R.
Published: February 2011

The Gough-Joule coefficients (1) at constant stress and (2) at constant strain are defined and methods of measurement of each on vulcanized rubbers are given. It is shown mathematically and experimentally that the ratio of (3) to (4) is equal to the “tangent” modulus. The quotient of the Gough-Joule coefficient at constant stress divided by the stress and the quotient of the Gough-Joule coefficient at constant strain divided by the strain are shown to be constants which are independent of the stress-strain-temperature conditions. Experimental data are given for stocks based on Hevea, GR-S, Neoprene-GN, Butyl Rubber, and Butaprene.
Light Phenomena on Elongating Vulcanized Rubbers
Authors: Van Rossem A.
Published: February 2011

A description is given of a light phenomenon, first observed by W. C. Smith, when carrying out tear tests on some loaded vulcanized rubbers in a dark room. This phenomenon has been studied more systematically by high-speed extension tests. It appears that this light effect has nothing to do with the choice of accelerators, but with the compounding ingredients of loaded vulcanized rubbers. In general, those compounding ingredients which belong to the filler class, such as whiting, talc, and ground barium sulfate, show this light phenomenon very distinctly, while vulcanized rubbers with reinforcing compounding ingredients, such as zinc oxide, titanium dioxide, and carbon black, do not show any light effect when quickly extended. In accordance with this, Kalite and Calcene, which behave as reinforcing compounding ingredients, do not show any light phenomenon. It seems probable, that, on elongating the vulcanized rubbers containing fillers, the adhesion of rubber-filler particle is broken, and electrical charges appear on an extremely large surface, which lead to innumerable discharges into surrounding vacuoles, causing the general light phenomenon observed.
The Hydrochlorination of Rubber in Latex
Authors: van Veersen G. J.
Published: February 2011

A careful consideration of the influence of solvents on the hydrochlorination of rubber in solution has led to a fundamentally new technical process for the preparation of rubber hydrochloride. If hydrogen chloride is passed through latex stabilized with cationic or non-ionic emulsifying agents, rubber hydrochloride is formed. The rate of reaction, which is slow at normal temperature and pressure, can be increased considerably by carrying out the reaction under pressure. From the fact that rubber hydrochloride prepared from latex has a chlorine content very near the theoretical value, it may be concluded that hydrochlorination of rubber in latex is not accompanied by cyclization.
Thermodynamics of Crystallization in High Polymers. VI. Incipient Crystallization in Stretched Vulcanized Rubber
Authors: Fox Thomas G. , Flory Paul J. , Marshall Robert E.
Published: February 2011

Experimental determination of the elongation at which crystallization commences in vulcanized rubber has been attempted through measurement of density changes by a hydrostatic method. The critical elongation for incipient crystallization appears to depend on the temperature, in approximate accordance with theoretical prediction. Crystallization sets in at an elongation well below that at which the stress-strain curve assumes a steep slope.
Free Retraction of Elongated Rubbers
Authors: Boonstra B. B. S. T.
Published: February 2011

The speed of retraction of the ends of elongated rubber rings relative to each other for a number of elastomers was measured at room temperature by a comparatively simple method. The results, plotted as elongation vs. time curves, indicate that the mechanism of retraction is complicated and cannot be described by a simple mathematical equation. In the present case the so-called permanent set plays a part in the retraction velocity. A mathematical equation is given to account for this phenomenon. Elasticity is judged in terms of speed of retraction and permanent set.
The Low-Temperature Performance of Butyl Inner Tubes
Authors: Adams R. J. , Buckler E. J. , Wanless G. G.
Published: February 2011

Standard Butyl inner tubes in passenger car service, when operated at temperatures below zero Fahrenheit for continued periods, develop buckles which may eventually cause chafing failures. This effect is believed to be due to increase in the viscous modulus compared with the elastic modulus of Butyl at low temperatures. The effect on performance of such factors as tire pressure, casing composition, and acceleration have been investigated, improved formulations consisting of highly plasticized, high-molecular-weight Butyl have been studied and correlations established between tube performance and physical characteristics, such as rebound, rate of retraction, modulus function, and oil viscosity. While commercial evaluation of such formulations is proceeding, other approaches are being studied by Canadian and United States groups, particularly involving polymers which may be brought to a more complete state of vulcanization.
The Interpretation of Plasticity Measurements
Authors: Scott J. R. , Whorlow R. W.
Published: February 2011

After consideration of the various factors whose influence must be included in any complete assessment of the fundamental flow properties of uncompounded raw rubber, a comparison is made of results from various instruments. It is shown that a plot of log (shear stress) against log (strain rate) is straight or slightly curved at low shear rates, but may be markedly convex to the log stress axis at higher rates. Reference is made to the limitations of the methods of Scott for the interpretation of the results of parallel-plate compression tests; attempts to apply the Nutting equation to the large strains in the usual compression tests with rubber are shown theoretically, and by experiments on materials of known characteristics, to be invalid. Consideration of the instruments available for factory control purposes shows that the one figure obtained from conventional tests is inadequate for the evaluation of a new mix or even a new plasticizing or mixing technique, and alternative procedures are considered; for the control of nominally identical batches a single figure may be adequate. Finally, the essential requirements for research and control instruments are compared, and available instruments in each group surveyed in the light of the earlier discussion.
New Types of Highly Elastic Substances, Vulcollans
Authors: Bayer O. , Müller E. , Petersen S. , Piepenbrink H. F. , Windemuth E.
Published: February 2011

It is shown that new types of highly elastic products with remarkable properties can be obtained by a process of diisocyanate poly-addition, which involves the transformation of linear polyesters of glycols and dicarboxylic acids with an excess of certain special “expansive” diisocyanates in the presence of a very small proportion of water. The terminally bifunctional polyesters react first with the diisocyanate, with resultant lengthening of the chains. A network is subsequently developed from urea groups, which are formed from isocyanate groups and water, and which then react with the diisocyanate. The chemical mechanism of this process is discussed in detail. In addition, the processing and possible applications of this new class of elastomers is reviewed.
Oxidation of Compounds Structurally Related to GR-S
Authors: Lawrence J. W. , Shelton J. Reid
Published: February 2011

The rates of oxidation of 1-phenyl-3-pentene, 1-phenyl-4-hexene, and 1-phenyl-3-vinylbutane have been measured at 100° C and 1 atmosphere of oxygen pressure. 1-Phenyl-2-butene has also been included to complete the sequence 1–4, 1–3, and 1–2 with respect to the structural relationship between the phenyl radical and the point of unsaturation. Information concerning the course of the reaction was obtained both from the rate data and from chemical analysis of the oxidized products. Three stages of oxidation were noted: (1) a very short induction period; (2) an autocatalytic stage which is characterized by a rapidly increasing rate and in which the primary products appear to be peroxides; and (3) a period characterized by a constant rate of oxygen absorption with the formation of such products as acids, esters, carbon dioxide, and water.
Oxidation Processes in Latex of Hevea Brasiliensis
Authors: de Haan-Homans L. N. S.
Published: February 2011

The occurrence of catalase, tyrosinase, oxidase and peroxidase in latex of Hevea brasiliensis has been investigated. These enzymes are present in fresh latex. With the exception of catalase they are accompanied by inhibitors, some of which are powerful reducing substances, and by nonenzymatical oxygen-absorbing substances. Thus latex contains a complicated redox system. Several properties of the enzymes and some properties of the reducing substances were determined. An explanation is given for the spontaneous blue discoloration which frequently appears on the surface of latex, and the possible significance of the results on the formation of the rubber in the tree is indicated.
Mechanical Stability Test for Hevea Latex
Authors: Dawson H. G.
Published: February 2011

The mechanical stability test is a rapid, simple method of estimating the colloidal stability or quality of Hevea latex by high-speed stirring. Latex particles start to agglomerate as soon as the peripheral speed of the agitator reaches a certain minimum value. Progressive flocculation continues until mechanical coagulation occurs. The end point is defined as the time in seconds required to coagulate 0.5 to 1.0 per cent of the total solids. If the shear is constant, the time is proportional to the colloidal stability, which depends upon the interfacial film between the latex particles and the serum. The mechanical stability time depends critically on the size, the total solids, and the temperature of sample.
Agreement in Detecting Glaucomatous visual Field Progression by using Guided Progression Analysis and Humphrey Overview Printout
Authors: lester Michele , Corallo Guido , Capris Elisabetta , Capris Paolo
Published: February 2011

Purpose

To examine the level of agreement among 3 clinicians in assessing glaucoma visual field progression by using 2 different methods.

Methods

Each visual field was assessed by Humphrey Field Analyzer (HFA), program SITA standard 30–2 or 24–2. In each printout the first 3 fields were excluded to minimize learning effect: the fourth and fifth full-threshold or SITA Standard examinations were used as baseline. Three clinicians assessed the progression status of each series using both HFA overview printouts and the guided progression analysis (GPA). The level of agreement among the clinicians was evaluated using a weighted kappa statistic (κ).

Results

A total of 510 tests, comprising 83 eyes with an average of 6.1 tests each, was assessed by the 3 specialists. The mean follow-up time was 5.8±1.75 years (mean ± standard deviation). When the intraobserver intermethod agreement was evaluated, κ ranged from 0.5 to 0.7. When the interobserver agreement was analyzed, if HFA overview printouts were used, κ ranged from 0.4 to 0.7. But when GPA was used, κ ranged from 0.2 to 0.6. The level of agreement on progression status between the clinicians was always higher when they used HFA overview printouts (median κ = 0.54) than when they used GPA (median κ=0.37).

Conclusions

Agreement among expert clinicians about visual field progression status was moderate when GPA printouts were used. Clinicians’ agreement about patients’ visual field progression status was better when HFA overview printouts were used than with GPA printouts.
Primary Uterine Inertia in Four Labrador Bitches
Authors: Davidson Autumn P.
Published: February 2011

Uterine inertia is a common cause of dystocia in the bitch and is designated as primary (i.e., uterine contractions fail to ever be initiated) or secondary (i.e., uterine contractions cease after a period of time but before labor is completed). The etiology of primary uterine inertia is not well understood. The accurate diagnosis of primary uterine inertia requires the use of tocodynamometry (uterine monitoring). Primary uterine inertia has been postulated to result from a failure of luteolysis resulting in persistently elevated progesterone concentrations. In this study, primary uterine inertia was diagnosed in a series of four bitches in which luteolysis was documented suggesting some other etiopathogenesis for primary uterine inertia.
Acute Necrotizing Myopathy in a Dog
Authors: Willamson Jill A. , Kaelble Monika , Chisholm Alex
Published: February 2011

A 9 yr old spayed female cocker spaniel presented for an acute onset of weakness. Rhabdomyolysis and myoglobinuria were found 36 hr after presentation. The dog was managed for several electrolyte and mineral abnormalities and rhabdomyolysis-induced acute renal failure. The diagnosis of idiopathic necrotizing myopathy was determined by histopathology and by the exclusion of underlying infectious agents and metabolic defects. The dog recovered completely from the acute crisis and acute renal failure.
Feline Cerebrovascular Disease: Clinical and Histopathologic Findings in 16 Cats
Authors: Altay Ulrike Michal , Skerritt Geoff C. , Hilbe Monika , Ehrensperger Felix , Steffen Frank
Published: February 2011

Sixteen cats with cerebrovascular disease confirmed via histology to be of nontraumatic and nonneoplastic origins are described. In addition, the anatomy of the arterial supply of the cat's brain is reviewed. It is suggested that this unique arterial design may influence the incidence of cerebrovascular accidents in this species. Of the 16 cats reviewed, seven cats had ischemic infarctions, five had hemorrhagic infarctions, and four were diagnosed with intracranial hemorrhage. The median age was 8 yr and 9.5 yr in cats with infarctions and intracranial hemorrhages, respectively. Clinical signs were severe, acute, consistent with the localization of the cerebrovascular lesion, and influenced by underlying pathology. Four cats with infarction showed lateralized neurologic signs. Four cats with infarctions were diagnosed with pulmonary disease antemortem and three cats had hyperthyroidism. Cerebrospinal fluid analysis and computed tomography scans were available in two cats. None of the infarctions were grossly visible. All cats with hemorrhagic infarcts had severe liver pathology and nephritis was identified in four cats. Hypoxia was a feature in four cats and one cat suffered cardiac failure. In conclusion, the clinical picture is influenced by the type of cerebrovascular disease, the localization of the intracranial lesions, and any underlying pathology.
Aspergillus fumigatus Bronchopneumonia in a Hellenic Shepherd Dog
Authors: Adamama-Moraitou Katerina K. , Pardali Dimitra , Day Michael J. , Denning David W. , Papazoglou Lysimachos , Papastefanou Anastasia , Rallis Timoleon S.
Published: February 2011

A 3 yr old intact female Hellenic shepherd dog was referred due to depression, partial anorexia, fever, and a mild productive cough of 2 mo duration. Thoracic radiographs showed increased opacity of all of the left lung lobes. Upon bronchoscopy, a sanguineous, purulent discharge was detected in the tracheal lumen with hyperplastic tissue narrowing the left main stem bronchus. Cultures were positive for bacteria (Bacillus spp. and Clostridium spp.) but negative for fungi. Due to the severity of the lesions, a complete left lung pneumonectomy was performed. Histopathological examination of the excised lung tissues revealed a severe granulomatous bronchopneumonia with numerous alveolar macrophages laden with structures stained positively by periodic acid-Schiff and Grocott stain that had morphology consistent with fungi. PCR and sequencing of internal transcribed spacer regions 1 and 2 from genetic material extracted from paraffin-embedded pulmonary tissue confirmed the presence of Aspergillus fumigatus. Itraconazole was administrated for 5.5 mo and the dog was clinically normal 26 mo after surgery.
Vascularized Ulnar Bone Grafts for Limb-Sparing Surgery for the Treatment of Distal Radial OsteosarcomaS
Authors: Hodge Susan C. , Degner Daniel , Walshaw Richard , Teunissen Brian
Published: February 2011

The objective of this retrospective study was to compare vascularized free or roll-in ulnar bone grafts for limb-sparing surgery in dogs with radial osteosarcoma with the cortical allograft, metal endoprosthesis, or distraction osteogenesis techniques. Overall, the ulnar graft techniques used in this study demonstrated excellent healing properties. Complications included recurrence of the tumor in 25% (2/8) of the dogs, metastasis in 50% (4/8) of the dogs, implant loosening in 37.5% (3/8) of the dogs, implant failure in 12.5% (1/8) of the dogs, and infection in 62.5% (5/8) of the dogs. Mean survival time was 29.3 mo (range, 9 to 61 mo). The mean metastasis-free interval was 33.67 mo (range, 8 to 54 mo). Tumors recurred locally in two dogs at 10 mo and 20 mo postoperatively. This study yielded similar long-term complications as other limb-sparing options (such as cortical allografts and metal endoprostheses) and allowed dogs to bear weight on the operated limb with acceptable limb function. More research is needed regarding specific healing times for ulnar vascularized grafts, time until implant removal, and the extent of radial bone that could ultimately be replaced by the ulna.
Diagnosis of Erythema Multiforme Associated with Thymoma in a Dog and Treated with Thymectomy
Authors: Tepper Laura C. , Spiegel Ian B. , Davis Garrett J.
Published: February 2011

A 7 yr old Labrador retriever initially presented for severe halitosis, mild ptylism, and depigmentation of the nasal planum. Erythema multiforme was diagnosed based on clinical signs and dermatopathology. Treatment was initiated but the condition did not resolve. Six months later, the dog was diagnosed with a mediastinal mass. Trucut biopsy was performed and histopathologic diagnosis was consistent with a thymoma. A median sternotomy was performed, the thymoma was excised, and the dog recovered well. Four months postoperatively, there were no longer any obvious erythema multiforme lesions and the skin condition was controlled without medication. Erythema multiforme may be a paraneoplastic disorder associated with thymoma in the dog, similar to thymoma-associated exfoliative dermatitis in the cat. Clinical signs of erythema multiforme may warrant performing thoracic radiographs or thoracic CT to rule out thymoma as an underlying cause.
Extraskeletal Osteosarcoma of the Heart Presenting as Infective Endocarditis
Authors: Timian Jessica , Yoshimoto Sean K. , Bruyette David S.
Published: February 2011

A 7 yr old castrated male Labrador retriever (35.6 kg) was evaluated for an acute onset of vomiting of 24 hr duration. On initial examination, the patient was febrile (103.8°F) and tachycardic (150 beats/min). Thoracic radiographs revealed left atrial enlargement with mild pulmonary infiltrates. The dog's condition worsened and repeat radiographs revealed worsening pulmonary infiltrates and pleural effusion. Treatment for heart failure was initiated. An echocardiogram showed a large 3 cm × 4 cm vegetation on the atrial surface of the posterior mitral valve. The patient was euthanized due to poor clinical appearance and infective endocarditis was suspected. Necropsy revealed an osteosarcoma of the posterior mitral valve, which cultured negative.
Hereditary Phosphofructokinase Deficiency in Wachtelhunds
Authors: Hillström Anna , Tvedten Harold , Rowe André , Giger Urs
Published: February 2011

Hereditary phosphofructokinase (PFK) deficiency was diagnosed in two Wachtelhund dogs and suspected in three related Wachtelhund dogs with exercise intolerance, hemolytic anemia, and pigmenturia. Severe, persistent reticulocytosis in light of only mild anemia together with hemoglobinuria after strenuous exercise suggested PFK deficiency. Low erythrocyte PFK activity together with low 2,3-diphosphoglycerate concentrations and a high hemoglobin-oxygen affinity confirmed the diagnosis. The PFK deficiency is due to a single missense mutation in the muscle-type PFK M-PFK gene in English springer and American cocker spaniels, whippets, and mixed-breed dogs; however, these PFK-deficient Wachtelhunds do not have the same PFK mutation.
Thermo‐oxidative decomposition kinetics of elastomeric composites based on styrene‐(ethylene‐butylene)‐styrene triblock copolymer and organomontmorillonite
Authors: Saikrasun Sunan , Amornsakchai Taweechai
Published: February 2011

The elastomeric nanocomposites based on organomontmorillonite (OMMT) and styrene‐(ethylene‐butylene)‐styrene (SEBS) thermoplastic elastomer were prepared by melt processing using maleic anhydride grafted SEBS (SEBS‐g‐MA) as compatibilizer. Thermo‐oxidative decomposition behavior of the neat components and the nanocomposites were investigated using thermogravimertic analysis (TGA) in air atmosphere. The isoconversional method is employed to study the kinetics of thermo‐oxidative degradation. The heating modes and the composition of nanocomposites were found to affect the kinetic parameters (Ea, lnA and n). The Ea and lnA values of SEBS, OMMT, and their composites are much higher under dynamic heating than under isothermal heating. The reaction order (n) of OMMT was lower than those of SEBS and their composites. The obtained TG profiles and calculated kinetic parameters indicated that the incorporation of OMMT into SEBS significantly improved the thermal stability both under dynamic heating and under isothermal heating. The simultaneously obtained DSC data showed that the enthalpy of thermal decomposition decreased with OMMT loading. No significant change in the nonisothermal and isothermal stability of the nanocomposites with addition of SEBS‐g‐MA. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Highly transparent and organosoluble polyimides derived from 2,2′‐disubstituted‐4,4′‐oxydianilines
Authors: Chen Jyh‐Chien , Rajendran Kuppachari , Chang Ya‐Hui , Huang Sheng‐Wen , Chern Yaw‐Tern
Published: February 2011

To improve the optical transparency and organosolubility of aromatic polyimides derived from 4,4′‐oxydianiline (4,4′‐ODA), two new aromatic diamines, 2,2′‐diiodo‐4,4′‐oxydianiline (DI‐ODA) and 2,2′‐bis[(p‐trifluoromethyl)phenyl]‐4,4′‐oxydianiline (BTFP‐ODA) were synthesized by using 4,4′‐ODA as a starting material. Novel polyimides were prepared from these two diamines with various commercially available aromatic dianhydrides via a one‐step high‐temperature polycondensation procedure. Most of these polyimides showed enhanced solubility in common organic solvents compared with those corresponding polyimides derived from 4,4′‐ODA. Especially, polyimide derived from BTFP‐ODA and rigid pyromellitic dianhydride (PMDA) was also soluble in DMF, DMAc, DMSO, NMP, and m‐cresol at room temperature. These polyimides had inherent viscosities from 0.41 to 1.26 dLg−1 in NMP or m‐cresol at 30°C. Transparent, flexible, and tough films can be obtained by casting from their DMAc or m‐cresol solutions. These films had the UV onset wavelengths in the range of 347–391 nm and the wavelengths at 80% transmission of 445–544 nm, indicating high optical transparency. They also exhibited good thermal stability with glass transition temperatures in the range of 260–327°C. The decomposition temperatures of these polyimides at 5% weight loss under nitrogen were 429–609°C. Because of the weak carbon‐iodine bond, polyimides derived from DI‐ODA decomposed at lower temperatures than polyimides derived from BTFP‐ODA. The effects of the substituents at the 2 and 2′ positions of 4,4′‐ODA on the properties of polyimides are also discussed. High optical transparency and good solubility combined with high thermal stability make these polyimides potential candidates for soft electronics applications. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Alcohophilic gels: Polymeric organogels composing carboxylic and sulfonic acid groups
Authors: Kabiri K. , Azizi A. , Zohuriaan‐Mehr M. J. , Marandi G. Bagheri , Bouhendi H.
Published: February 2011

Polymeric organogels based on acrylic acid (AA) and sodium allyl sulfonate (SAS) were prepared through solution polymerization using a persulfate initiator and a polyethylene glycol diacrylate (PEGDA) crosslinker. FTIR spectroscopy, elemental, and rheological analyses were used for a preliminary characterization. Thermo‐mechanical analysis was also carried out for characterizing samples. Glass transition temperature (Tg) of copolymer was decreased after acid treatment which could be attributed to detachment of ion pairs during the post‐treatment. Due to counterion binding of Na+ to form ionomer, the poly(AA‐SAS) gels showed no polyelectrolyte behavior to have high swelling capacity in conventional alcohols, i.e., ethanol and methanol. It was postulated that modification via removing Na+ could help breaking ion pair aggregates which leads to swelling enhancement. Thus, poly(AA‐SAS) was treated with hydrochloric acid to remove (Na+) counterions. This modification led to the gel transform from ionomer regime to a polyelectrolyte regime in which free mobile ions were existed in the network. The gel swelling capacity was increased due to raise of mobile ions after the treatment. It was found that both of the acid concentration and treatment time had constructive influence on the gel alcohophilicity. The acid‐treated samples could imbibe ethanol and methanol as high as 25.8 and 39.5 g/g, respectively. They may be superior candidates for applications such as pharmaceuticals gels and fire starters. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
The architecture of hydroxy‐functionalized aPS‐b‐random copolymer‐b‐PE via one‐pot strategy combining living free radical polymerization with coordination polymerization
Authors: Ma Lifu , Liu Weijiao , Yi Jianjun , Wang Hongli , Huang Qigu , Gao Kejing , Yang Wantai
Published: February 2011

The copolymerization of styrene with ethylene was promoted by CpTiCl3/BDGE/Zn/MAO catalyst system combining free radical polymerization with coordination polymerization via sequential monomer addition strategy in one‐pot. The effect of polymerization conditions such as temperature, time, ethylene pressure, and Al/Ti molar ratio on the polymerization performance was investigated. The hydroxy‐functionalized aPS‐b‐random copolymer‐b‐PE triblock copolymer was obtained by solvent extraction and determined by GPC, DSC, WAXD, and 13C‐NMR. The DSC result indicated that the aPS‐b‐random copolymer‐b‐PE had a Tg at 87°C and a Tm at 119°C which attributed to the Tg of aPS segment and the Tm of PE segment, respectively. The microstructure of the hydroxy‐functionalized aPS‐b‐random copolymer‐b‐PE was further confirmed by WAXD, 13C‐NMR, and 1H‐NMR analysis; and these results demonstrated that the obtained block copolymer consisted of aPS segment, S‐E random copolymer segment, and crystalline PE segment. The connection polymerization of the hydroxy‐functionalized aPS with random copolymer‐b‐PE was revealed by GPC results. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Common genetic polymorphisms in pre‐microRNAs and risk of cervical squamous cell carcinoma
Authors: Zhou Bin , Wang Kana , Wang Yanyun , Xi Mingrong , Zhang Zhu , Song Yaping , Zhang Lin
Published: February 2011

MicroRNAs (miRNAs) function as gene regulator and they participate in diverse biological pathways. Common single nucleotide polymorphisms (SNPs) in pre‐microRNAs may change their property through altering miRNAs expression and/or maturation. We conducted a pilot study to test whether SNPs in pre‐microRNAs were associated with cervical squamous cell carcinoma (CSCC). Genotypes of three SNPs in pre‐miRNAs (hsa‐miR‐196a2 rs11614913 C/T, hsa‐miR‐499 rs3746444 A/G, and hsa‐miR‐146a rs2910164 G/C) in 226 CSCC patients and 309 control subjects were determined with the use of PCR‐restriction fragment length polymorphism (RFLP) assay. Significantly increased CSCC risks were found to be associated with G allele of rs3746444 and G allele of rs2910164 (P = 0.017, OR = 1.454, and P = 0.016, OR = 1.355, respectively). Increased CSCC risks were associated with them in different genetic model (P = 0.0004, OR = 1.98 for rs3746444 in an overdominant model, and P = 0.024, OR = 2.10 for rs2910164 in a codominant model, respectively). Results of stratified analyses revealed that rs2910164 is associated with tumor differentiation and lymph node status (P = 0.043, OR = 2.08, and a borderline P = 0.057, OR = 0.41, respectively). No association between rs11614913 and CSCC risk was observed. The present study provides evidence that rs3746444 and rs2910164 are associated with CSCC, indicating that common genetic polymorphisms in pre‐microRNAs contribute to the pathogenesis of CSCC. Mol. Carcinog. © 2011 Wiley‐Liss, Inc.
Progression and prognostic factors of motor impairment, disability and quality of life in newly diagnosed Parkinson's disease
Authors: Post Bart , Muslimovic Dino , van Geloven Nan , Speelman Johannes D. , Schmand Ben , de Haan Rob J. ,   on behalf of the CARPA‐study group
Published: February 2011

Objective:

To determine progression and prognostic factors of progression rate of motor impairment, disability, and quality of life (QoL) in patients with newly diagnosed Parkinson's disease.

Methods:

A group of 126 patients with newly diagnosed PD recruited from outpatient clinics participated in this 3‐year prospective cohort study. Motor impairment was rated with the Unified Parkinson Disease Rating Scale Motor‐Examination. Disability was rated using the Schwab and England Activities of Daily Living Scale, the AMC Linear Disability Score. QoL was assessed with the Parkinson's Disease Quality of Life questionnaire. Linear mixed model analyses were conducted to identify determinants of progression rate of motor impairment, disability, and poor QoL.

Results:

Motor impairment progressed with 3 points per year. There was a slight progression of disability and QoL during 3 years of follow‐up. Female sex was a prognostic factor for slower progression of motor impairment and QoL. Older age at onset showed to prognosticate faster progression of disability and impaired QoL. Furthermore, independent of follow‐up time, older age at onset was associated with worse motor impairment; nondopaminergic reactive symptoms (Axial impairment) were associated with more disability and poorer QoL; comorbidity showed relation with disability and QoL but to a lesser extent; self‐reported mood symptoms were associated with poorer QoL; and disease duration correlated with motor impairment.

Conclusions:

Motor impairment, disability, and QoL of newly diagnosed Parkinson patients show progression in the first 3 years. Older age at onset predicts worse progression rate of disability and impaired QoL over time. Female sex predicts slower progression of motor impairment and less decline of QoL. © 2011 Movement Disorder Society
Parkinson's disease sleep scale—validation of the revised version PDSS‐2
Authors: Trenkwalder Claudia , Kohnen Ralf , Högl Birgit , Metta Vinod , Sixel‐Döring Friederike , Frauscher Birgit , Hülsmann Julia , Martinez‐Martin Pablo , Chaudhuri Kallol Ray
Published: February 2011

Background:

The previous Parkinson's disease sleep scale (PDSS) is a 15‐item visual analogue scale that assesses the profile of nocturnal disturbances in Parkinson's disease (PD) patients.

Objective:

To extend the scale so that it becomes a frequency measure scale with five categories and encompasses unmet needs such as restless legs syndrome, akinesia, pain, and sleep apnea.

Methods:

For validation of the PDSS‐2, PD patients' ratings and investigators' interviews were compared to ratings from a semistructured interview with a caregiver/partner, and to related scales. PDSS‐2 was repeated for test‐retest‐reliability after 1–3 days.

Results:

A total of 113 PD patients showed a mean (SD) total score of 16.5 (±8.9) (range: 2–40) indicating mild to moderate sleep disturbances. PDSS‐2 item‐total correlation for proving internal consistency was satisfactory (correlations >0.30). From a factor analysis, three subscales were derived: (1) “motor problems at night,” (2) “PD symptoms at night” and (3) “disturbed sleep.” The alpha coefficient for the total score was 0.73, for subscales 0.47 to 0.66. The test‐retest‐reliability intra‐class‐coefficient for the total score was 0.80, with 0.69 and 0.77 within the subscales. For discriminative validity, significant differences were found in the PDSS‐2 total score depending on CGI and Hoehn and Yahr severity levels. A comparison between caregivers' and patients' ratings was carried out.

Conclusion:

The PDSS‐2, with an extended spectrum of nocturnal disabilities and easier use for patients, is a reliable, valid, precise, and potentially treatment‐responsive tool for measuring sleep disorders in PD. © 2011 Movement Disorder Society
Revisiting gap locations in amino acid sequence alignments and a proposal for a method to improve them by introducing solvent accessibility
Authors: Hijikata Atsushi , Yura Kei , Noguti Tosiyuki , Go Mitiko
Published: February 2011

In comparative modeling, the quality of amino acid sequence alignment still constitutes a major bottleneck in the generation of high quality models of protein three‐dimensional (3D) structures. Substantial efforts have been made to improve alignment quality by revising the substitution matrix, introducing multiple sequences, replacing dynamic programming with hidden Markov models, and incorporating 3D structure information. Improvements in the gap penalty have not been a major focus, however, following the development of the affine gap penalty and of the secondary structure dependent gap penalty. We revisited the correlation between protein 3D structure and gap location in a large protein 3D structure data set, and found that the frequency of gap locations approximated to an exponential function of the solvent accessibility of the inserted residues. The nonlinearity of the gap frequency as a function of accessibility corresponded well to the relationship between residue mutation pattern and residue accessibility. By introducing this relationship into the gap penalty calculation for pairwise alignment between template and target amino acid sequences, we were able to obtain a sequence alignment much closer to the structural alignment. The quality of the alignments was substantially improved on a pair of sequences with identity in the “twilight zone” between 20 and 40%. The relocation of gaps by our new method made a significant improvement in comparative modeling, exemplified here by theBacillus subtilisyitF protein. The method was implemented in a computer program, ALAdeGAP (ALignment with Accessibility dependent GAp Penalty), which is available athttp://cib.cf.ocha.ac.jp/target_protein/. Proteins 2011; © 2011 Wiley‐Liss, Inc.
Percutaneous Drainage versus Emergency Cholecystectomy for the Treatment of Acute Cholecystitis in Critically Ill Patients: Does it Matter?
Authors: Melloul E. , Denys A. , Demartines N. , Calmes J.‐M. , Schäfer M.
Published: February 2011

Background

The aim if this study was to compare percutaneous drainage (PD) of the gallbladder to emergency cholecystectomy (EC) in a well‐defined patient group with sepsis related to acute calculous/acalculous cholecystitis (ACC/AAC).

Methods

Between 2001 and 2007, all consecutive patients of our ICU treated by either PD or EC were retrospectively analyzed. Cases were collected from a prospective database. Percutaneous drainage was performed by a transhepatic route and EC by open or laparoscopic approach. Patients’ general condition and organ dysfunction were assessed by two validated scoring systems (SAPS II and SOFA, respectively). Morbidity, mortality, and long‐term outcome were systematically reviewed and analyzed in both groups.

Results

Forty‐two patients [median age = 65.5 years (range = 32–94)] were included; 45% underwent EC (ten laparoscopic, nine open) and 55% PD (n = 23). Both patient groups had similar preoperative characteristics. Percutaneous drainage and EC were successful in 91 and 100% of patients, respectively. Organ dysfunctions were similarly improved by the third postoperative/postdrainage days. Despite undergoing PD, two patients required EC due to gangrenous cholecystitis. The conversion rate after laparoscopy was 20%. Overall morbidity was 8.7% after PD and 47% after EC (P = 0.011). Major morbidity was 0% after PD and 21% after EC (P = 0.034). The mortality rate was not different (13% after PD and 16% after EC, P = 1.0) and the deaths were all related to the patients’ preexisting disease. Hospital and ICU stays were not different. Recurrent symptoms (17%) occurred only after ACC in the PD group.

Conclusions

In high‐risk patients, PD and EC are both efficient in the resolution of acute cholecystitis sepsis. However, EC is associated with a higher procedure‐related morbidity and the laparoscopic approach is not always possible. Percutaneous drainage represents a valuable intervention, but secondary cholecystectomy is mandatory in cases of acute calculous cholecystitis.
On the future of “omics”: lipidomics
Authors: Griffiths William J. , Ogundare Michael , Williams Christopher M. , Wang Yuqin
Published: February 2011

Following in the wake of the genomic and proteomic revolutions new fields of “omics” research are emerging. The metabolome provides the natural complement to the genome and proteome, however, the extreme physicochemical diversity of the metabolome leads to a subdivision of metabolites into compounds soluble in aqueous solutions or those soluble in organic solvents. A complete molecular and quantitative investigation of the latter when isolated from tissue, fluid or cells constitutes lipidomics. Like proteomics, lipidomics is a subject which is both technology driven and technology driving, with the primary technologies being mass spectrometry, with or without on‐line chromatography and computer‐assisted data analysis. In this paper we will examine the underlying fundamentals of different lipidomic experimental approaches including the “shotgun” and “top‐down” global approaches, and the more targeted liquid chromatography – or gas chromatography – mass spectrometry approaches. Application of these approaches to the identification of in‐born errors of metabolism will be discussed.
Brain white matter abnormalities in paediatric Gaucher Type I and Type III using diffusion tensor imaging
Authors: Davies Elin Haf , Seunarine Kiran K. , Banks Tina , Clark Chris A. , Vellodi Ashok
Published: February 2011

Objective

Biomarkers to monitor neurological dysfunction in Neuronopathic Gaucher disease (NGD) are lacking. Diffusion tensor imaging (DTI) is a technique which allows us to probe the microstructure of the white‐matter of the brain, in‐vivo. The aim of this study was to investigate the value of DTI to visualise and quantify white matter integrity in children with NGD and Type I Gaucher.

Design

DTI was performed and fractional anisotropy (FA), mean diffusivity (MD), axial (λaxial) diffusivity and radial (λradial) diffusivity maps calculated. Tract‐based spatial statistics (TBSS) was used to perform a voxel‐wise statistical analysis of the main white matter structures compared to age‐sex matched control groups.

Setting

The study was performed at Great Ormond Street Children's Hospital NHS Trust

Patients

Four NGD and three Type I Gaucher paediatric patients were recruited

Results

The findings suggest the presence of microstructural white matter changes in NGD patients primarily in the middle cerebellar peduncles compared to an age‐sex matched control group. This finding is relevant to the clinical manifestation of ataxia seen in NGD. Diffuse non‐specific changes were seen in the Type I patients, but without a focal point.

Conclusions

This study is the first to use DTI to examine the Gaucher brain. While the numbers studied are small, the results suggest that DTI may be an attractive surrogate marker of NGD, worthy of further exploration for use in clinical studies.
Brain activity for chronic knee osteoarthritis: Dissociating evoked pain from spontaneous pain
Authors: Parksl Elle L. , Gehal Paul Y. , Balikil Marwan N. , Katzl Jeffrey , Schnitzerl Thomas J. , Apkarianl A. Vania
Published: February 2011

Chronic pain is a hallmark of osteoarthritis (OA), yet little is known about its properties and representation in the brain. Here we use fMRI combined with psychophysics to study knee pain in fourteen OA patients and nine healthy controls. Mechanical painful pressure stimuli were applied to the knee in both groups and ratings of evoked pain and related brain activity examined. We observe that psychophysical properties and brain activation patterns of evoked pain are essentially the same between OA patients and healthy subjects, and between worse and better OA knees. In OA patients, stimulus‐related brain activity could be distinguished from brain activity associated with spontaneous pain. The former activated brain regions commonly observed for acute painful stimuli in healthy subjects, while the spontaneous pain of OA engaged prefrontal‐limbic regions closely corresponding to areas observed for spontaneous pain in other chronic pain conditions, such as chronic back pain and post‐herpetic neuralgia. Arthritis‐related clinical characteristics of knee OA also mapped to prefrontal‐limbic regions. In a subgroup of patients (n =6) we examined brain activity changes for a 2‐week, repeat measure, cyclooxygenase‐2 inhibitor (valdecoxib) therapy. Treatment decreased spontaneous pain for the worse knee and clinical characteristics of OA, and increased blood and csf levels of the drug which correlated positively with prefrontal‐limbic brain activity. These findings indicate dissociation between mechanically induced and spontaneous OA knee pain, the latter engaging brain regions involved in emotional assessment of the self, and challenge the standard clinical view regarding the nature of OA pain.
Pandemic (H1N1) 2009 virus infection during pregnancy in South India
Authors: Pramanick Angsumita , Rathore Swati , Peter John V. , Moorthy Mahesh , Lionel Jessie
Published: February 2011

Objective

To assess the clinical profile of pregnant/puerperal women from a semi‐urban Indian population who were infected with pandemic (H1N1) 2009 virus (P[H1N1]2009v) and to evaluate their outcome.

Methods

In a cross‐sectional study, 566 women (79 pregnant/puerperal, 487 nonpregnant) who presented to a tertiary care hospital with influenza‐like illness were tested for P(H1N1)2009v by real‐time reverse transcriptase polymerase chain reaction. Outcomes measures were the maternal mortality and the perinatal mortality rate (PMR).

Results

Twenty (25%) pregnant/puerperal and 144 (30%) nonpregnant women tested positive for P(H1N1)2009v, with 5 pregnant and 3 postpartum women requiring admission to the intensive care unit (ICU). P(H1N1)2009v‐related mortality was higher in pregnant than nonpregnant women (25% versus 8%; P = 0.04). In the pregnant/puerperal cohort, factors associated with death included delayed presentation (median 6 days versus 1.5 days in survivors; P = 0.007), need for ICU admission (P = 0.004), need for ventilation (P = 0.001), and renal failure (P = 0.001). The PMR was 55.5/1000 births compared with 33.5/1000 births in the hospital overall during the study period.

Conclusion

In a low‐income country, P(H1N1)2009v infection in pregnancy is associated with considerable mortality. Delayed presentation to a tertiary care center, lack of awareness, and restricted access to treatment might have contributed to the high mortality.
Treatment and outcome of stage Ia1 squamous cell carcinoma of the uterine cervix
Authors: Haller Herman , Krašević Maja , Mamula Ozren , Brnčić‐Fischer Alemka , Eminović Senija , Manestar Miljenko
Published: February 2011

Objective

To evaluate the treatment and clinical outcome of patients with FIGO stage IA1 cervical squamous cell carcinoma (SCC).

Methods

Medical records, including 5‐year follow‐up, were reviewed for 276 patients with stage IA1 SCC.

Results

As definitive surgery, 152 (55.1%), 72 (26.1%), 40 (14.5%), and 12 (4.3%) patients underwent conization, hysterectomy, hysterectomy with pelvic lymphadenectomy (PL), and radical hysterectomy with PL, respectively.

Among these groups, the 5‐year recurrence‐free rate was 94.1%, 98.6%, 95%, and 100%, respectively, and the survival rate was 98.7%, 98.6%, 100%, and 100%, respectively. Recurrent disease was identified among 12 (4.3%) patients, and was related to the depth of invasion (P < 0.001). Eleven (4.0%) of 276 patients were found to have lymph vascular space invasion (LVSI). There were no positive lymph nodes among 52 patients who underwent PL, including those with LVSI. Conization was followed by hysterectomy in 49 patients. In these patients, residual intraepithelial neoplasia was found in 18 women, 3 of whom had no involved margins on previous conization. In the group of patients treated by conization, recurrence correlated with the status of the endocervical and lateral cone margin (P < 0.001).

Conclusion

As a conservative approach, conization is an effective and reasonable treatment option for stage IA1 SCC, especially in actively reproductive women.
Implementation of the Zambia Electronic Perinatal Record System for comprehensive prenatal and delivery care
Authors: Chi Benjamin H. , Vwalika Bellington , Killam William P. , Wamalume Chibesa , Giganti Mark J. , Mbewe Reuben , Stringer Elizabeth M. , Chintu Namwinga T. , Putta Nande B. , Liu Katherine C. , Chibwesha Carla J. , Rouse Dwight J. , Stringer Jeffrey S.A.
Published: February 2011

Objective

To characterize prenatal and delivery care in an urban African setting.

Methods

The Zambia Electronic Perinatal Record System (ZEPRS) was implemented to record demographic characteristics, past medical and obstetric history, prenatal care, and delivery and newborn care for pregnant women across 25 facilities in the Lusaka public health sector.

Results

From June 1, 2007, to January 31, 2010, 115 552 pregnant women had prenatal and delivery information recorded in ZEPRS. Median gestation age at first prenatal visit was 23 weeks (interquartile range [IQR] 19–26). Syphilis screening was documented in 95 663 (83%) pregnancies: 2449 (2.6%) women tested positive, of whom 1589 (64.9%) were treated appropriately. 111 108 (96%) women agreed to HIV testing, of whom 22% were diagnosed with HIV. Overall, 112 813 (98%) of recorded pregnancies resulted in a live birth, and 2739 (2%) in a stillbirth. The median gestational age was 38 weeks (IQR 35–40) at delivery; the median birth weight of newborns was 3000 g (IQR 2700–3300 g).

Conclusion

The results demonstrate the feasibility of using a comprehensive electronic medical record in an urban African setting, and highlight its important role in ongoing efforts to improve clinical care.