Extensive Investigations (extensive + investigation)

Distribution by Scientific Domains
Distribution within Medical Sciences


Selected Abstracts


Novel Thermoplastic Composites from Commodity Polymers and Man-Made Cellulose Fibers

MACROMOLECULAR SYMPOSIA, Issue 1 2006
Hans-Peter Fink
Abstract Summary: A new class of fibre reinforced commodity thermoplastics suited for injection moulding and direct processing applications has been developed using man-made cellulosic fibres (Rayon tire yarn, Tencel, Viscose, Carbacell) and thermoplastic commodity polymers, such as polypropylene (PP), polyethylene (PE), high impact polystyrene (HIPS), poly(lactic acid) (PLA), and a thermoplastic elastomer (TPE) as the matrix polymer. For compounding, a specially adapted double pultrusion technique has been employed which provides composites with homogeneously distributed fibres. Extensive investigations were performed with Rayon reinforced PP in view of applications in the automotive industry. The Rayon-PP composite is characterized by high strength and an excellent impact behaviour as compared with glass fibre reinforced PP, thus permitting applications in the field of engineering thermoplastics such as polycarbonate/acrylonitrile butadiene styrene blends (PC/ABS). With the PP based composites the influence of material parameters (e.g. fibre type and load, coupling agent) were studied and it has been demonstrated how to tailor the desired composite properties as modulus and heat distortion temperature (HDT) by varying the fibre type or adding inorganic fillers. Man-made cellulose fibers are also suitable for the reinforcement of further thermoplastic commodity polymers with appropriate processing temperatures. In case of PE modulus and strength are tripled compared to the neat resin while Charpy impact strength is increased five-fold. For HIPS mainly strength and stiffness are increased, while for TPE the property profile is changed completely. With Rayon reinforced PLA, a fully biogenic and biodegradable composite with excellent mechanical properties including highly improved impact strength is presented. [source]


Presumed interaction of fusidic acid with simvastatin

ANAESTHESIA, Issue 6 2008
A. J. Burtenshaw
Summary A 63-year-old man was admitted 6 weeks after an elective abdominal aortic aneurysm repair following which methicillin resistant Staphylococcus aureus (MRSA) had been cultured from the aneurysmal sac. He had been commenced on a course of fusidic acid at discharge in addition to his ongoing statin prescription and presented 4 weeks later with symptoms consistent with rhabdomyolysis. Severe rhabdomyolysis was confirmed and despite prolonged and complicated critical care management, his treatment was unsuccessful. Extensive investigations ruled out other known causes of this clinical presentation and failed to identify any other precipitating cause of rhabdomyolysis. We believe the most likely cause was hepatic inhibition of the CYP3A4 hepatic isoenzyme by fusidic acid resulting in an acute severe rise in plasma simvastatin level and extensive myocellular damage. Increasing MRSA colonisation and infection rates together with increased statin usage have the potential to increase the incidence of this presumed drug interaction. [source]


Murine mesenchymal stem cells isolated by low density primary culture system

DEVELOPMENT GROWTH & DIFFERENTIATION, Issue 6 2006
Mohamadreza Baghaban Eslaminejad
Murine mesenchymal stem cells (mMSC) and the difficult task of isolation and purification of them have been the subject of rather extensive investigation. The present study sought to isolate these cells from two different mouse strains, one outbred and the other inbred, primarily through a relatively simple but novel approach, the most important feature of which was the low density primary culture of bone marrow cells. For this purpose, mononuclear cells from either NMRI or BALB/c bone marrow were plated at about 500 cells per well of 24-well plates and incubated for 7 days. At this point, the fibroblastic clones that had emerged were pooled together and expanded through several subcultures. To investigate the mesenchymal nature, we differentiated the cells into the osteoblastic, chondrocytic and adipocytic lineages in different subcultures up to passage 10. According to the results, 1 week after culture initiation, several clones each comprising several fibroblastic cells appeared in each plate. The cells from different passages were capable of differentiating into corresponding skeletal tissues. In the present investigation, the best culture condition for maximum proliferation and also the expression of certain surface marker on isolated cells were examined. In this term the two murine strains showed some differences. [source]


Inhaled insulin as adjunctive therapy in subjects with type 2 diabetes failing oral agents: a controlled proof-of-concept study

DIABETES OBESITY & METABOLISM, Issue 5 2006
M. Hausmann
Aim:, This controlled proof-of-concept study investigated inhaled insulin (INH) as adjunctive therapy to existing oral antidiabetic agents in subjects with type 2 diabetes. Methods:, Twenty-four subjects with type 2 diabetes [19 men and 5 women, 56.1 ± 6.6 years, body mass index 32.7 ± 4.2 kg/m2, glycosylated haemoglobin (HbA1c) 8.4 ± 0.8% (mean ± s.d.)] inadequately controlled by metformin and/or sulfonylureas were randomized to receive additional therapy with either INH administered preprandially using a metered-dose inhaler (MDI), or insulin glargine (GLA) injected subcutaneously at bedtime for 4 weeks. Both inhaled and injected insulin doses were titrated to predefined blood glucose (BG) targets. Results:, INH and GLA improved metabolic control to a similar extent. Mean daily BG decreased by 2.8 mmol/l in the INH group (p < 0.001) and by 2.4 mmol/l in the GLA group (p < 0.001). Accordingly, fasting BG (,2.7 vs. ,3.6 mmol/l for INH vs. GLA), preprandial- and 2-h postprandial BG, HbA1c (,1.23 vs. ,1.05%), body weight (,1.9 vs. ,2.3 kg) and serum fructosamine were similarly and significantly reduced in both groups (p < 0.05). Triglycerides decreased significantly with INH (,1.15 ,mol/l; p < 0.001) but not with GLA [,0.52 ,mol/l; not significant (NS)]. Incidence rates of adverse events did not differ significantly, and there were no indications of respiratory tract irritation. Conclusions:, In subjects with type 2 diabetes inadequately controlled by oral agents, preprandial administration of INH delivered by a MDI provided a comparable metabolic control to bedtime GLA and did not show any safety concerns during a 4-week treatment. These results warrant a more extensive investigation of preprandial treatment with INH in longer term studies. [source]


Bilateral medial temporal lobe damage does not affect lexical or grammatical processing: Evidence from amnesic patient H.M.

HIPPOCAMPUS, Issue 4 2001
Elizabeth A. Kensinger
Abstract In the most extensive investigation to date of language in global amnesia, we acquired data from experimental measures and examined longitudinal data from standardized tests, to determine whether language function was preserved in the amnesic patient H.M. The experimental measures indicated that H.M. performed normally on tests of lexical memory and grammatical function, relative to age- and education-matched control participants. Longitudinal data from four Wechsler subtests (Information, Comprehension, Similarities, and Vocabulary), that H.M. had taken 20 times between 1953 (preoperatively) and 2000, indicated consistent performance across time, and provided no evidence of a lexical memory decrement. We conclude that medial temporal lobe structures are not critical for retention and use of already acquired lexical information or for grammatical processing. They are, however, required for acquisition of lexical information, as evidenced in previous studies revealing H.M.'s profound impairment at learning new words. Hippocampus 2001;11:347,360. © 2001 Wiley-Liss, Inc. [source]


Theoretical study on the partial potential energy surface and formation mechanism of the reactive resonance state of HO + CH4 , H2O + CH3 system

INTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY, Issue 2 2008
Xi Lu
Abstract In the course of an extensive investigation aimed at understanding the detailed mechanism of a prototypical polyatomic reaction, several remarkable observations were uncovered. To interpret these findings, we surmise the existence of a reactive resonance in this polyatomic reaction. The concerned system is HO + CH4 , H2O + CH3, of which the partial potential energy surface is constructed by the coupling between vibrational models and reactive coordinates. Then we explain the formation mechanism of the reactive resonance state by the partial potential energy surface. Finally, we estimated the lifetime of the resonance state, and it is about 45fs. The study of the reactive resonance in a polyatomic reaction is more than just an extension from a typical atom + diatom reaction. As shown here, it holds great promise to disentangle the elusive intramolecular vibrational dynamics of the transient collision complex in the critical transition-state region. © 2007 Wiley Periodicals, Inc. Int J Quantum Chem, 2008 [source]


BIOCHEMICAL CHARACTERIZATION OF BORAGE (BORAGO OFFICINALIS L.) SEEDS

JOURNAL OF FOOD BIOCHEMISTRY, Issue 3 2009
BAYA MHAMDI
ABSTRACT Gas chromatography,mass spectrometry analysis of seed Borago officinalis essential oil (EO) revealed the presence of 16 volatile components. ,-Caryophyllene (26%) and p-cymene-8-ol (19.7%) represented the major components, while nonadecane (0.7%) and hexanol (0.7%) were the minor ones. The EO composition was characterized by higher abundance of oxygenated monoterpenes (27.7%), followed by sesquiterpenes (26%). Fatty acid composition showed the predominance of linoleic (35.4%), oleic (24.2%) and ,-linolenic (20.4%) acids. Polyphenols were analyzed by reversed-phase high-performance liquid chromatography after acid hydrolysis of phenolic acid esters. Six phenolic acids were identified in seed extract and rosmarinic acid was the predominant one with 1.65 mg/g dry matter weight equivalent to 33% of total phenolic acids. PRACTICAL APPLICATIONS Borage (Borago officinalis L.) is of great interest because of its medicinal and nutritional properties. In fact, thanks to its characteristic composition in fatty acids, particularly high levels of gamma-linolenic acid in its seed oil, borage has gained importance. The potent consumers of this medicinal plant are hypertensive and hypercholesterolemic people. Borage consumption is also recommended for people suffering from rheumatism and eczema. Unfortunately, the knowledge about antioxidative/antiradical properties of borage is very scanty. So, recently, an extensive investigation was focused on the antioxidant properties of borage extracts. These extracts showed excellent antioxidant properties and their effects were attributed to their phenolic constituents. These antioxidants can be concentrated, either as crude extracts or individual phenolic compounds, to be used in highly unsaturated oils such as marine oils. Furthermore, borage consumption has been reported as a possible gastric cancer protective factor. [source]


Peripheral nervous system involvement as presenting symptom of systemic B-cell lymphoma

JOURNAL OF THE PERIPHERAL NERVOUS SYSTEM, Issue 2 2004
C Casellato
Peripheral nervous system involvement has been reported in systemic B or T cell lymphoma and may result from intraneural localization of lymphoma resulting in meningo-radiculopathy or mononeuropathies, or manifest as a sensory-motor polyneuropathy sometimes mimicking chronic inflammatory demyelinating polyneuropathy. We report two patients with a previously unknown NHL presenting in both with a stepwise progressive asymmetric multiradiculoneuropathy initially misdiagnosed as inflammatory radiculopathy. A 58-year-old man presented with a 2 year history of stepwise progressive peroneal sensory loss, impotence, and lower limb painful asymmetric neuropathy. Lumbosacral MRI was normal. Electrophysiological studies were consistent with an axonal multiradiculoneuropathy while CSF examinations repeatedly showed increased protein levels (80,91 mg/dl) with slightly increased white cells (<10 mm3) but no malignant cell. The patient repeatedly failed to respond to steroids although he consistently deteriorated at their suspension. An MRI performed 2 years later when multiple cranial nerve palsies appeared showed bilateral T1 and T2 hyperintensities in the brain and cervical spinal cord. An extensive investigation for neoplasm was negative. The patient died from an intracranial hemorrhage during anticoagulant therapy for deep vein thrombosis. Autoptic studies revealed a widespread non-Hodgkin's type B lymphoma with massive systemic and neural involvement including cauda equina and spinal cord. A 54-year-old man presented with a 1 year history of impotence, urinary incontinence, progressive asymmetric painful distal sensorimotor impairment at four limbs and prominent weight loss. Four previous CSF examinations revealed increased protein levels (80,100 mg/dl), and slightly but inconsistently increased white cells (1,11/mm3) but no malinant cells. Steroids were repeatedly ineffective although the patient consistently deteriorated whenever steroids were discontinued. On admission electrophysiological studies showed an axonal asymmetric polyradiculoneuropathy. Brain and spinal MRI was normal while bone marrow biopsy and aspiration disclosed a B cell lymphoma. [source]


Novel movement disorder of the lower lip: Is it epilepsia partialis continua?

MOVEMENT DISORDERS, Issue 7 2005
Clues from a secondary case
Abstract A 28-year-old woman developed an acute-onset novel movement disorder of the lower lip mimicking focal dystonia. Investigations showed it to be a presentation of epilepsia partialis continua occurring in association with agenesis of the corpus callosum. It responded favorably to anti-epileptic drug therapy. Recently, Kleopa and Kyriakides1 reported on 4 patients who developed sudden-onset movement disorder characterized by a tonic sustained, lateral and outward protrusion of half of the lower lip. They failed to find any causative factors, despite extensive investigation. Treatment with anticholinergics, clonazepam, and botulinum toxin injection failed to improve the movement disorder. I present an additional case of similar focal movement disorder occurring in the presence of agenesis of the corpus callosum. A scalp electroencephalogram revealed focal epileptic activity, and the movement disorder responded favorably to treatment with antiepileptic drugs. © 2005 Movement Disorder Society [source]


Thirty-five years in bioelectromagnetics research

BIOELECTROMAGNETICS, Issue 1 2007
C-K. Chou
Abstract For 35 years, I have been involved in various bioelectromagnetics research projects including acute and long-term radiofrequency (RF) bioeffects studies, dosimetry, exposure systems, MRI safety, cancer studies involving hyperthermia and electrochemical treatment, development of RF exposure and measurement standards, and product compliance. My first study demonstrated that effects on isolated nerve and muscle preparations were due to thermal effects of RF exposure. The recording of cochlear microphonics in animals shows the mechanical nature of the microwave auditory effect. In 1992, we published the results of a large-scale lifetime study in which 100 rats were sham-exposed and 100 rats were exposed for 21 h/day for 25 months to a pulsed RF signal. In dosimetry studies, human models were employed as well as many animal species including mice, rats, rabbits, monkeys, and birds of many sizes. Cancer hyperthermia studies demonstrated that knowledge of temperature distribution was crucial for successful treatment. Research on electrochemical treatment of tumors with direct current involved cellular, animal, and clinical studies. Over the past few decades, there has been rather extensive investigation of the public health impact of RF exposure. In my opinion, future research in bioelectromagnetics should place greater emphasis on medical applications. Bioelectromagnetics © 2006 Wiley-Liss, Inc. [source]


The in,uence of ,1 -acid glycoprotein on collagenase-3 activity in early rheumatoid arthritis

BIOMEDICAL CHROMATOGRAPHY, Issue 6 2003
J. Louise Haston
Abstract The concentration and glycosylation of ,1 -acid glycoprotein (AGP) alter signi,cantly during in,ammation. A de,nitive physiological role for AGP remains elusive and is the subject of extensive investigation. This study investigated the in,uence of AGP on the activity of collagenase-3, an important mediator of cartilage destruction in rheumatoid arthritis. AGP was isolated from normal and rheumatoid plasma. Fucosylation was determined by high pH anion-exchange chromatography; sialylation was assessed following enzymatic digest. Rheumatoid AGP displayed elevated fucosylation and sialylation compared with normal. The in,uence of each sample on collagenase-3 activity was measured ,uorometrically. AGP in,uenced collagenase-3 catalysis and collagen binding, with catalytic activity correlating with fucosylation. Rheumatoid AGP exhibited less ef,cient inhibition than normal plasma AGP. It is hypothesized that AGP within rheumatoid synovial ,uid may be inadequate to prevent excessive cartilage destruction and hence may exacerbate the disease process. Copyright © 2003 John Wiley & Sons, Ltd. [source]


French-English relations in business-interest associations, 1965,2002

CANADIAN PUBLIC ADMINISTRATION/ADMINISTRATION PUBLIQUE DU CANADA, Issue 4 2002
William D. Colentan
The Royal Commission on Bilingualism and Biculturalism carried out an extensive investigation of language practices in the private sector and in voluntary associations. Using the royal commission's work on associations representing the general interests of business, this article examines language practices of these associations three decades after the royal commission's studies were published. The authors argue that the cordiality found between French and English in general business associations in the late 1960s continues to be the rule in these types of associations today. This cordiality, however, is rooted in a change in linguistic relations. Federal-level associations tend to have accommodated institutional bilingualism but retain English as their language of work. Quebec-based associations have moved to conform to official unilingualism. Moreover, the number of non-francophones in positions of authority in the Quebec groups has diminished, with executive structures now being dominated by francophones. Sommaire: Si nous avons une assez bonne connaissance de I'impact du bilinguisme officiel A I'échelle fedérale et de I'unilinguisme officiel au Québec sur la pratique lan-gagiére du gouvemement, nous ne savons pas trb bien si ces modifications des poli-tiques linguistiques ont entraîné des changements dans la pratique IangagèPre des organismes de la société civile. La Commission royale d'enquête sur le bilinguisme ct Ie biculturalisme a entrepris une recherche extensive sur les pratiques langagières dans le secteur privé et les associations bbnévoles. Grdce au travail de la Commission royale sur les associations representant les intérêts généraux des entreprises, cette ètude examine les pratiques langagières de ces associations, trois décennies après la publication des études de la Commission royale d'enquête. Les auteurs font remarquer que la cordialité observée entre le français et l'anglais au sein des associations cornmerciales vers la fin des années 1960 continue a être la règle dans ces types d'associations aujourd'hui. Cependant, cette cordialité est enracinée dans une modification des relations linpistiques. Les associations A 1,échelle féd érale ont tendance a satisfaire les exigences du bilinguisme institutionnel, mais conservent I'anglais cornme langue de travail. Les associations établies au Québec ont pris des rnesures pour se conformer à I'unilinguisme officiel. En outre, les non francophones sont moins nombreux à occuper des positions d'autorité dans les groupes au Québec, les structures de direction étant maintenant dominées par des francophones. [source]


Aetiology in severe and mild mental retardation: a population-based study of Norwegian children

DEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 2 2000
Petter Strømme MD PhD
The aetiology of mental retardation (MR) was studied in a population-based series of Norwegian children derived from 30 037 children born between 1980 and 1985. The study included 178 children, 79 with severe MR (SMR) (IQ<50) and 99 with mild MR (MMR) (IQ 50 to 70). Aetiology was divided into two main groups: biopathological and unspecified. The biopathological group comprised 96% of SMR and 68% of MMR, and was subdivided into prenatal (70% and 51%), perinatal (4% and 5%), and postnatal damage (5% and 1%), and a group of undetermined timing of the damaging event (18% and 11%). Single-gene disorders accounted for 15 of the 63 children with genetic disorders, including X-linked recessive in six. During the course of the study, at least 27 (15%) children had their aetiological diagnosis revised. Gestational age <32 weeks, birthweight <1500g, and Apgar scores 0 to 2 at 1 and 5 minutes implied a significantly increased risk of MR, but contributed to only 4% of the children in the study. Decreased birthweight (1500 to 2499 g) and Apgar scores 3 to 6 at 1 and 5 minutes showed increased probability of MR. Despite extensive investigations, 4% of SMR and 32% of MMR were not identified with any biological markers and were considered as unspecified MR, several most probably representing the lower end of the normal IQ distribution in the population. [source]


Case of eosinophilic granulomatous enterocolitis caused by Strongyloides stercoralis infection with marked hypoalbuminemia and ascites

DIGESTIVE ENDOSCOPY, Issue 3 2004
Nuthapong Ukarapol
We report a 10-year-old boy presenting with generalized pitting edema, ascites, abdominal pain, and chronic mucous diarrhea for 4 weeks. He had underlying diseases of hemoglobin E and juvenile rheumatoid arthritis and had been treated with immunosuppressive agents for a long period of time, including prednisolone and methotrexate. After extensive investigations, Strongyloides stercoralis infection, leading to protein-losing enteropathy and eosinophilic granulomatous enterocolitis, was diagnosed. In the present report, we demonstrate early colonoscopic findings, revealing patchy erythema and small raised mucosal nodules with erosions at the cecum. Histopathological study showed open ulceration with cryptitis, intense infiltration of eosinophils and histiocytes with granuloma formation, in which Strongyloides stercoralis larvae were noted. [source]


Neighbour-regulated mortality: the influence of positive and negative density dependence on tree populations in species-rich tropical forests

ECOLOGY LETTERS, Issue 8 2003
Halton A. Peters
Abstract Density-dependent mortality has long been posited as a possible mechanism for the regulation of tropical forest tree density. Despite numerous experimental and phenomenological investigations, the extent to which such mechanisms operate in tropical forests remains unresolved because the demographical signature of density dependence has rarely been found in extensive investigations of established trees. This study used an individual-based demographical approach to investigate the role of conspecific and heterospecific neighbourhood crowding on tree mortality in a Panamanian and a Malayan tropical forest. More than 80% of the species investigated at each site were found to exhibit density-dependent mortality. Furthermore, most of these species showed patterns of mortality consistent with the Janzen,Connell hypothesis and the rarely explored hypothesis of species herd protection. This study presents some of the first evidence of species herd protection operating in tree communities. [source]


Pharmacokinetics, dose-range, and mutagenicity studies of methylphenidate hydrochloride in B6C3F1 mice,,

ENVIRONMENTAL AND MOLECULAR MUTAGENESIS, Issue 8 2008
Mugimane G. Manjanatha
Abstract Methylphenidate hydrochloride (MPH) is one of the most frequently prescribed pediatric drugs for the treatment of attention deficit hyperactivity disorder. In a recent study, increased hepatic adenomas were observed in B6C3F1 mice treated with MPH in their diet. To evaluate the reactive metabolite, ritalinic acid (RA) of MPH and its mode of action in mice, we conducted extensive investigations on the pharmacokinetics (PK) and genotoxicity of the drug in B6C3F1 mice. For the PK study, male B6C3F1 mice were gavaged once with 3 mg/kg body weight (BW) of MPH and groups of mice were sacrificed at various time points (0.25,24 hr) for serum analysis of MPH and RA concentrations. Groups of male B6C3F1 mice were fed diets containing 0, 250, 500, 1,000, 2,000, or 4,000 ppm of MPH for 28 days to determine the appropriate doses for 24-week transgenic mutation studies. Also, the micronucleus frequencies (MN-RETs and MN-NCEs), and the lymphocyte Hprt mutants were determined in peripheral blood and splenic lymphocytes, respectively. Mice fed 4,000 ppm of MPH lost significant BW compared to control mice (P < 0.01). There was a significant increase in the average liver weights whereas kidneys, seminal vesicle, testes, thymus, and urinary bladder weights of mice fed higher doses of MPH were significantly lower than the control group (P , 0.05). There was no significant increase in either the Hprt mutant frequency or the micronucleus frequency in the treated animals. These results indicated that although MPH induced liver hypertrophy in mice, no genotoxicity was observed. Environ. Mol. Mutagen., 2008. Published 2008 Wiley-Liss, Inc. [source]


Ultrasonic treatment of waste activated sludge

ENVIRONMENTAL PROGRESS & SUSTAINABLE ENERGY, Issue 2 2006
Raf Dewil
Abstract Activated sludge processes are key technologies to treat wastewater. These biological processes produce huge amounts of waste activated sludge (WAS), now commonly called biosolids. Mechanical, thermal, and/or chemical WAS conditioning techniques have been proposed to reduce the sludge burden. The ultrasonic treatment of WAS is quite novel. The present paper reports on extensive investigations using an ultrasonic treatment of WAS, to study its potential to meet one or all of four objectives: (1) reduce WAS quantities; (2) achieve a better dewaterability; (3) provoke a release of soluble chemical oxygen demand (COD) from the biosolids, preferably transformed into biodegradable organics; and (4) possibly destroy the filamentous microorganisms responsible for sludge bulking. Although meeting these objectives would help to solve the problems cited, the energy consumption could be a considerable drawback: the paper will thus assess whether all or some objectives are met, and at what operational cost. A literature survey defines the occurring phenomena (cavitation) and the important operation parameters [such as frequency, duration, specific energy input (SE)]. The experiments are carried out in a batch reactor of volume up to 2.3 L. The ultrasonic equipment consisted of a generator, a converter, and a sonotrode, supplied by Alpha Ultrasonics under the brand name of Telsonic. Three different kinds of sludge were tested, with different concentrations of dry solids (DS) between approximately 3.5 and 14 g DS/L WAS. Ultrasonic energy was introduced in a continuous manner (against possible pulsed operation). The major operational parameters studied include duration of the ultrasonic treatment and specific energy input. The applied frequency was set at 20 kHz. The release of COD from the WAS phase into the filtrate phase is a function of the specific energy input with yields of nearly 30% achievable at SE values of 30,000 kJ/kg DS. A major fraction of the COD is transformed into biodegradable organics (BOD). The reduction in DS fraction of the sludge is proportional to the COD release rates. Although the DS content is reduced, the dewaterability of the sludge is not improved. This reflects itself in increased filtration times during vacuum filtration and in increased values of the capillary suction time (CST). This more difficult dewaterability is the result of considerably reduced floc sizes, offering an extended surface area: more surface water is bound (CST increases) and the filterability decreases as a result of clogging of the cake. To reach the same dryness as for the untreated cake, the required dosage of polyelectrolyte is nearly doubled when the SE of the ultrasound treatment is increased from 7500 to 20,000 kJ/kg DS. The ultrasonic reduction of filamentous WAS organisms is not conclusive and very little effect is seen at low intensities and short treatment durations. Microscopic analysis of the WAS identified the dominant presence of Actynomyces. The release of soluble COD and BOD certainly merit further research. © 2006 American Institute of Chemical Engineers Environ Prog, 2006 [source]


Severe Epilepsy in X-Linked Creatine Transporter Defect (CRTR-D)

EPILEPSIA, Issue 6 2007
Maria Margherita Mancardi
Disorders of creatine synthesis or its transporter resulting in neurological impairment with mental retardation and epilepsy have only been recognized in recent years. To date, the epileptic disorder observed in creatine transporter deficiency (CRTR-D) has been described as a mild phenotype with infrequent seizures and favorable response to common antiepileptic drugs. We report on a 5 year-old boy with known speech delay who presented with severe and refractory epilepsy. After extensive investigations, metabolite analysis and brain 1H-MRS suggested CRTR-D, which was confirmed by the detection of a known pathogenic mutation in the SLC6A8 gene (c.1631C>T; p.Pro544Leu). [source]


Minimal diagnostic criteria for myelodysplastic syndromes and separation from ICUS and IDUS: update and open questions

EUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 7 2009
P. Valent
Abstract Although a classification for myelodysplastic syndromes (MDS) has been proposed by several working groups and by the World Health Organization (WHO), with criteria useful to discriminate between disease variants, the important issue of minimal diagnostic criteria of MDS has only recently been addressed. In the current article, proposed minimal diagnostic criteria for MDS are discussed together with two conditions that do not meet these criteria, although cytopenia or dysplasia is present. These two conditions, idiopathic cytopenia of unknown significance and idiopathic dysplasia of unknown significance should be kept in mind as a provisional (potential) diagnosis in patients with suspected MDS. Both conditions can progress to frank MDS over time. Therefore, once diagnosed, these patients should have a haematological follow-up. The diagnosis MDS, on the other hand, needs to be based on robust criteria and exclusion of all other causes of cytopenia and dysplasia, which requires detailed and sometimes extensive investigations, including a bone marrow biopsy, cytogenetic analyses, molecular studies and flow cytometry. [source]


Prognostic factors in patients with small hepatocellular carcinoma treated by percutaneous ethanol injection

JOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 11 2002
Hitoshi Kuriyama
Abstract Background: Percutaneous ethanol injection (PEI) has been widely performed and is now accepted as a viable alternative to hepatic resection in patients with small hepatocellular carcinomas (HCC). However, only a few extensive investigations have been conducted regarding the prognostic factors for HCC patients treated with PEI. Methods: We investigated the prognostic factors in 100 patients with small HCC who had undergone PEI. Univariate analysis and multivariate analysis with Cox's proportional hazards model were used to determine the factors potentially related to survival. For clinical application, a prognostic index was calculated based on the regression coefficients of the independent variables identified from the multivariate analysis. Results: Median survival time and 1, 3 and 5 year survival rates were 71 months and 100, 84 and 62%, respectively. Among the 15 potential prognostic variables investigated, only three variables, namely a serum albumin level ,,3.5 g/dL, the presence of tumor stain and a serum glutamic oxaloacetic transaminase level>,66 IU/L, were identified as factors independently associated with a shorter survival. A prognostic index based on the regression coefficients of these three factors was proposed to classify patients into three groups, those with a good (5 year survival rate 91%), intermediate (64%) and poor prognosis (22%). Conclusions: The results of the present study may be useful in predicting the survival of HCC patients treated with PEI and in the design and analysis of future clinical trials of PEI for HCC. © 2002 Blackwell Publishing Asia Pty Ltd [source]


An Integrative Analysis of the Effects of Auxin on Jasmonic Acid Biosynthesis in Arabidopsis thaliana

JOURNAL OF INTEGRATIVE PLANT BIOLOGY, Issue 1 2006
Jun Liu
Abstract Auxin and jasmonic acid (JA) are two plant phytohormones that both participate in the regulation of many developmental processes. Jasmonic acid also plays important roles in plant stress response reactions. Although extensive investigations have been undertaken to study the biological functions of auxin and JA, little attention has been paid to the cross-talk between their regulated pathways. In the few available reports examining the effects of auxin on the expression of JA or JA-responsive genes, both synergetic and antagonistic results have been found. To further investigate the relationship between auxin and JA, we adopted an integrative method that combines microarray expression data with pathway information to study the behavior of the JA biosynthesis pathway under auxin treatment. Our results showed an overall down regulation of genes involved in JA biosynthesis, providing the first report of a relationship between auxin and the JA synthesis pathway in Arabidopsis seedlings. (Managing editor: Ya-Qin Han) [source]


Altered knee kinematics in ACL-deficient non-copers: A comparison using dynamic MRI

JOURNAL OF ORTHOPAEDIC RESEARCH, Issue 2 2006
Peter J. Barrance
Abstract Kinematics measured during a short arc quadriceps knee extension exercise were compared in the knees of functionally unstable ACL-deficient patients, these patients' uninjured knees, and uninjured control subjects' knees. Cine phase contrast dynamic magnetic resonance imaging, in combination with a model-based tracking algorithm developed by the authors, was used to measure tibiofemoral kinematics as the subjects performed the active, supine posture knee extension exercise in the terminal 30 degrees of motion. Two determinants of tibiofemoral motion were measured: anterior/posterior location of the tibia relative to the femur, and axial rotation of the tibia relative to the femur. We hypothesized that more anterior tibial positioning, as well as differences in axial tibial rotation patterns, would be observed in ACL-deficient (ACL-D) knees when compared to uninjured knees. Multifactor ANOVA analyses were used to determine the dependence of the kinematic variables on (i) side (injured vs. uninjured, matched by subject in the control group), (ii) flexion angle measured at five-degree increments, and (iii) subject group (ACL-injured vs. control). Statistically significant anterior translation and external tibial rotation (screw home motion) accompanying knee extension were found. The ACL-D knees of the injured group exhibited significantly more anterior tibial positioning than the uninjured knees of these subjects (average difference over extension range,=,3.4,±,2.8 mm, p,<,0.01 at all angles compared), as well as the matched knees of the control subjects. There was a significant effect of interaction between side and subject group on A/P tibial position. We did not find significant differences in external tibial rotation associated with ACL deficiency. The changes to active joint kinematics documented in this entirely noninvasive study may contribute to cartilage degradation in ACL-D knees, and encourage more extensive investigations using similar methodology in the future. © 2005 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res [source]


Proton Conductivity Measurements in Yttrium Barium Cerate by Impedance Spectroscopy

JOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 11 2002
W. Grover Coors
Proton-conducting solid-electrolyte perovskite ceramics based on acceptor-doped barium and strontium cerates have become the focus of extensive investigations as candidate materials for fuel cells that operate at moderate temperatures. To assess the suitability of a material for this application, it is necessary that bulk electrolyte conductivity be measured at the operating temperature. However, very little reliable published conductivity data exist above 600°C. Protonic conductivity in yttrium-doped barium cerate has been observed to be less at high temperatures than would be expected, based on the activation energy and preexponential for hydrogen transport at temperatures <300°C. Conductivity data obtained from impedance spectroscopy on BaCe0.9Y0.1O3,, over the extended temperature range of 100°,900°C are presented. An Arrhenius plot of the data shows two distinct linear regions, suggesting that two different rate-limiting processes occur in series with a break-over transition at ,250°C. The decrease in conductivity is apparently not due to dehydration. An activation energy for protonic transport of 0.26 eV, about one-half of the low-temperature value, is proposed, based on curve fitting of the high-temperature data. [source]


Influence of testing parameters on the corrosion rate of magnesium alloys

MATERIALS AND CORROSION/WERKSTOFFE UND KORROSION, Issue 6 2004
M. Kühlein
Abstract In sodium chloride solutions alloy composition, phases, microstructure and grain size influence the corrosion behaviour of magnesium alloys. Concentration and distribution of the critical impurities iron, nickel and copper affect the corrosion performance strongly. Salt spray tests according to ASTM B 117 or DIN 50021 are used to control quality of magnesium alloys. Results of these tests often estimate alloy subcontractors and are therefore very important to placing. Standards specify test solution, test temperature and position of specimens during test in the salt spray chamber. Standards not prescribe preparation of test specimens, exposure period, handling of the specimens after salt spray test nor the interpretation of the results. Results of salt spray tests can be only compared, provided that test conditions are exactly given. Whether the standards fulfil the above described criteria, will be shown by extensive investigations. Therefore the influence of exposure period, surface condition and microstructure was investigated. [source]


Awns play a dominant role in carbohydrate production during the grain-filling stages in wheat (Triticum aestivum)

PHYSIOLOGIA PLANTARUM, Issue 4 2006
Xiaojuan Li
In wheat (Triticum aestivum L), the leaves particularly flag leaves have been considered to be the key organs contributing to higher yields, whereas awns have been considered subsidiary organs. Compared with extensive investigations on the assimilation contribution of leaves, the photosynthetic characteristics of awns have not been well studied. In this study, we investigated the ultrastructure of chloroplasts, oxygen evolution, and phosphoenolpyruvate carboxylase [phosphoenolpyruvate carboxylase (PEPCase) EC 4.1.1.31)] activity in both flag leaves and awns during the ontogenesis of wheat. Transmission electron microscope observations showed initial increases in the sizes of grana and the degree of granum stacks from the florescence-emergence stage both in flag leaves and in awns, followed by the breakdown of membrane systems after the milk-development stage. The results of oxygen evolution assays revealed that in both organs, the rate of photosynthesis increased in the first few stages and then decreased, but the decrease occurred much earlier in flag leaves than in awns. A PEPCase activity assay demonstrated that the activity of PEPCase was much higher in awns than in flag leaves throughout ontogeny; the value was particularly high at the late stages of grain filling. Our results suggest that awns play a dominant role in contributing to large grains and a high grain yield in awned wheat cultivars, particularly during the grain-filling stages. [source]


Decreased oxygen saturation as a result of haemoglobin Titusville

THE CLINICAL RESPIRATORY JOURNAL, Issue 4 2008
H. Avellan-Hietanen
Abstract Introduction:, Our patient was admitted to the hospital due to shortness of breath. Although partial pressure of oxygen in arterial blood was normal, oxygen saturation measured with pulse oximetry (SpO2) was markedly decreased. SpO2 and oxygen saturation of arterial blood (SaO2) stayed low during monitoring even with an increased fraction of oxygen in inspired air. Methods:, Report of a case. Results:, After extensive investigations, a rare haemoglobin variant, haemoglobin Titusville, with decreased oxygen binding capacity was discovered. This is the first haemoglobin Titusville case reported in Scandinavian countries. Please cite this paper as: Avellan-Hietanen H, Aittomaki J, Ekroos H, Aittomäki K, Turpeinen U, Kalkkinen N and Sovijärvi A. Decreased oxygen saturation as a result of haemoglobin Titusville. The Clinical Respiratory Journal 2008; 2: 242,244. [source]


Total Duodenectomy with Enteric Duct Drainage: A Rescue Operation for Duodenal Complications Occurring after Pancreas Transplantation

AMERICAN JOURNAL OF TRANSPLANTATION, Issue 3 2010
U. Boggi
Duodenal graft complications (DGC) occur frequently after pancreas transplantation but rarely cause graft loss. Graft pancreatectomy, however, may be required when DGC compromise recipient's safety. We herein report on two patients with otherwise untreatable DGC in whom the entire pancreas was salvaged by means of total duodenectomy with enteric drainage of both pancreatic ducts. The first patient developed recurrent episodes of enteric bleeding, requiring hospitalization and blood transfusions, starting 21 months after transplantation. The disease causing hemorrhage could not be defined, despite extensive investigations, but the donor duodenum was eventually identified as the site of bleeding. The second patient was referred to us with a duodenal stump leak, 5 months after transplantation. Two previous surgeries had failed to seal the leak, despite opening a diverting stoma above the duodenal graft. Thirty-nine and 16 months after total duodenectomy with dual duct drainage, respectively, both patients are insulin-independent and free from abdominal complaints. Magnetic resonance pancreatography shows normal ducts both basal and after intravenous injection of secretin. The two cases presented herein show that when DGC jeopardize pancreas function or recipient safety, total duodenectomy with enteric duct drainage may become an option. [source]


Proteus in the World of Proteins: Conformational Changes in Protein Kinases

ARCHIV DER PHARMAZIE, Issue 4 2010
Matthias Rabiller
Abstract The 512 protein kinases encoded by the human genome are a prime example of nature's ability to create diversity by introducing variations to a highly conserved theme. The activity of each kinase domain is controlled by layers of regulatory mechanisms involving different combinations of post-translational modifications, intramolecular contacts, and intermolecular interactions. Ultimately, they all achieve their effect by favoring particular conformations that promote or prevent the kinase domain from catalyzing protein phosphorylation. The central role of kinases in various diseases has encouraged extensive investigations of their biological function and three-dimensional structures, yielding a more detailed understanding of the mechanisms that regulate protein kinase activity by conformational changes. In the present review, we discuss these regulatory mechanisms and show how conformational changes can be exploited for the design of specific inhibitors that lock protein kinases in inactive conformations. In addition, we highlight recent developments to monitor ligand-induced structural changes in protein kinases and for screening and identifying inhibitors that stabilize enzymatically incompetent kinase conformations. [source]


Isolated symptomatic cutaneous disease in hypereosinophilic syndrome

AUSTRALASIAN JOURNAL OF DERMATOLOGY, Issue 1 2010
Veronica Preda
ABSTRACT A 41-year-old Phillipino man presented with a 3-year history of a relapsing and remitting generalized chronic pruritic erythematous papular and plaque-like eruption. Investigations showed a persistently elevated eosinophil count. His disease was limited to cutaneous involvement with an absence of demonstrable internal organ involvement, despite extensive investigations and multidisciplinary review. Other causes of eosinophilia were excluded. A diagnosis of idiopathic hypereosinophilic syndrome was made. Our patient's presentation raises a number of issues related to hypereosinophilic syndrome. In particular, relating to managing hypereosinophilic syndrome and the challenge of minimizing therapy side-effects. Our case highlights the considerable morbidity of untreated isolated cutaneous disease, for which he was hospitalized with suicidal ideations. In a minority of reports, skin involvement is the only manifestation of hypereosinophilic syndrome. [source]


Inhibition of Amyloid Fibrillization of Hen Egg-White Lysozymes by Rifampicin and p -Benzoquinone

BIOTECHNOLOGY PROGRESS, Issue 3 2007
Valerie H. Lieu
It has been reported that more than 20 different human proteins can fold abnormally, resulting in the formation of pathological deposits and several lethal degenerative diseases. Despite extensive investigations on amyloid fibril formation, the detailed molecular mechanism remained rather elusive. The current research, utilizing hen egg-white lysozymes as a model system, is aimed at exploring inhibitory activities of two potential molecules against lysozyme fibril formation. We first demonstrated that the formation of lysozyme amyloid fibrils at pH 2.0 was markedly enhanced by the presence of agitation in comparison with its quiescent counterpart. Next, via numerous spectroscopic techniques and transmission electron microscopy, our results revealed that the inhibition of lysozyme amyloid formation by either rifampicin or its analogue p -benzoquinone followed a concentration-dependent fashion. Furthermore, while both inhibitors were shown to acquire an anti-aggregating and a disaggregating activity, rifampicin, in comparison with p -benzoquinone, served as a more effective inhibitor against in vitro amyloid fibrillogenesis of lysozyme. It is our belief that the data reported in this work will not only reinforce the findings validated by others that rifampicin and p -benzoquinone serve as two promising preventive molecules against amyloid fibrillogenesis, but also shed light on a rational design of effective therapeutics for amyloidogenic diseases. [source]