bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of physiological media on the stability of surface-adsorbed DNA-dendron-gold nanoparticles
Authors: Singh Baljit , Hussain Nasir , Sakthivel Thiagarajan , Florence Alexander T
Published: January 2004

Plasmid DNA was adsorbed onto 87-nm gold nanoparticles to which were adsorbed a layer of novel cationic dendrons. The behaviour of this DNA-dendron-gold system in cell culture media has been described. Adsorption onto the gold nanoparticles of lipophilic cationic dendrons, with either 8 [(C12)3Lys7(NH2)8] or 16 [(C12)3Lys15(NH2)16] free amino groups on their outer surfaces and incorporating a nuclear localization signal peptide (NLS), resulted in positively charged nanoparticles with a corresponding small increase in particle size. Evidence suggested that the interaction between the gold nanoparticles and the dendron was mediated by hydrophobic forces. With an increase in ionic strength, the apparent particle size of the dendron-stabilized-gold particles increased, but at higher salt concentrations than plain gold sols. Addition of plasmid DNA did not markedly reduce the surface potential of the dendron-gold complex but resulted in an approximately 10–20% increase in hydro-dynamic diameter. Increasing ionic strength increased the apparent size of the DNA-dendron-gold particles, up to a maximum diameter of approximately 900 nm. Importantly, in cell culture media the size of the DNA-dendron-gold nanoparticles increased markedly, as surface potential was reduced. The presence of serum components partially ameliorated these effects, possibly due to steric stabilization of the particles. Release of the DNA from the complex was compromised in cell culture media (compared with water). This, coupled with the flocculation of the carrier, demonstrated the importance of testing delivery systems in the presence of relevant physiologically based fluids before cell culture or in-vivo studies.
Expression dynamics ofWOXgenes mark cell fate decisions during early embryonic patterning inArabidopsis thaliana
Authors: Haecker Achim , Groß-Hardt Rita , Geiges Bernd , Sarkar Ananda , Breuninger Holger , Herrmann Marita , Laux Thomas
Published: January 2004

During embryonic pattern formation, the main body axes are established and cells of different developmental fates are specified from a single-cell zygote. Despite the fundamental importance of this process, in plants, the underlying mechanisms are largely unknown. We show that expression dynamics of novel WOX (WUSCHEL related homeobox) gene family members reveal early embryonic patterning events in Arabidopsis. WOX2 and WOX8 are co-expressed in the egg cell and zygote and become confined to the apical and basal daughter cells of the zygote, respectively, by its asymmetric division. WOX2 not only marks apical descendants of the zygote, but is also functionally required for their correct development,suggesting that the asymmetric division of the plant zygote separates determinants of apical and basal cell fates. WOX9 expression is initiated in the basal daughter cell of the zygote and subsequently shifts into the descendants of the apical daughter apparently in response to signaling from the embryo proper. Expression of WOX5 shows that identity of the quiescent center is initiated very early in the hypophyseal cell, and highlights molecular and developmental similarities between the stem cell niches of root and shoot meristems. Together, our data suggest that during plant embryogenesis region-specific transcription programs are initiated very early in single precursor cells and that WOX genes play an important role in this process.
Reaction of an Overcrowded Distibene with Elemental Sulfur and Crystallographic Analysis of the Sulfurization Products
Authors: Sasamori Takahiro , Mieda Eiko , Takeda Nobuhiro , Tokitoh Norihiro
Published: January 2004

The reaction of a kinetically stabilized distibene bearing 2,6-bis[bis(trimethylsilyl)methyl]-4-[tris(trimethylsilyl)methyl]phenyl (denoted as Bbt) groups with elemental sulfur resulted in the formation of three types of sulfurization products containing two antimony atoms. The first structural identification of the 1,2,4,3,5-trithiadistibolane derivative was achieved by X-ray crystallographic analysis.
Thermally Reversible Photochromism of Pyrazole Derivatives
Authors: Yokoyama Yasushi , Kurimoto Yuko , Saito Yasuyo , Katsurada Manabu , Okada Itaru , Osano Yasuko T , Sasaki Chizuko , Yokoyama Yayoi , Tukada Hideyuki , Adachi Masafumi , Nakamura Shinichiro , Murayama Tetsuo , Harazono Toshie , Kodaira Tetsuya
Published: January 2004

Ethyl 4-formyl-1,3-dimethylpyrazole-5-carboxylate showed coloration upon 366-nm light irradiation in the solid state at room temperature. The red color disappeared either by melting or dissolving into solvents. The initiation of coloration is most likely based on a photochemical intramolecular hydrogen abstraction by the formyl oxygen from the methyl group on C-3. It also exhibited coloration in 2-methyltetrahydrofuran matrix at low temperature.
Binary Regiocontrol in the Reaction between Pentadienyltin and Imines by Lewis Acids and N-Substituents
Authors: Nishigaichi Yutaka , Ishihara Masahiko , Fushitani Shigeo , Uenaga Kenji , Takuwa Akio
Published: January 2004

Binary regiocontrolled pentadienylation of imines with a pentadienyltin reagent was achieved. While N-phenyl imines afforded ε-adducts (1,3-dienes) exclusively under Lewis acidic conditions, the combination of N-tosyl imines and indium or zinc chloride as a Lewis acid gave γ-adducts (1,4-dienes) preferentially.
A 1H NMR Study on the Electronic State of a Chloride-bridged Tetrakis(acetamidato)dirhodium Complex
Authors: Yamauchi Miho , Takazaki Yasuaki , Yang Zhiyong , Kawamura Takashi , Ikeda Ryuichi
Published: January 2004

A temperature dependence of 1H NMR spin-lattice relaxation time in a zig-zag chain of chloride-bridged tetrakis(acetamidato)dirhodium was measured. The observed 1H relaxation was well explained by the fluctuation of the magnetic dipolar interaction between proton and paramagnetic electron spins, where each unpaired spin is coupled by the one-dimensional antiferromagnetic interaction above 35 K. The slight change of the electronic state in the Rh dimer was observed below 35 K.
Synthesis and Characterization of Triplet Germylene-bridged Diiron Complexes and Singlet Stannylene-bridged Diiron Complexes
Authors: Mohamed Bahaa A S , Kikuchi Mami , Hashimoto Hisako , Ueno Keiji , Tobita Hiromi , Ogino Hiroshi
Published: January 2004

Photoreaction of CpFe(CO)2Me with sterically congested R2GeH2 [R = 2,4,6-C6H2iPr3 (Tip), 2,4,6-C6H2Me3 (Mes)] afforded paramagnetic germylene-bridged diiron complexes having a triplet ground state, Cp2Fe2(μ-CO)2(μ-GeR2) (3a, R = Tip; 3b, R = Mes), while the analogous reaction with R2SnH2 afforded diamagnetic complexes Cp2Fe2(CO)2(μ-CO)(μ-SnR2) (trans-5a, R = Tip; trans-5b, R = Mes). The structure of 3a was determined by X-ray crystallography.
Influence of Metallo Core Variation on 1-Methylimidazole Ligation to the Iron(III) in Porphyrin, Porphycene, Corrphycene, and Hemiporphycene
Authors: Neya Saburo , Hoshino Tyuji , Hata Masayuki , Funasaki Noriaki
Published: January 2004

Binding of 1-methylimidazole to five-coordinate iodo-Fe(III) complexes of porphyrin and three porphyrin isomers was spectrophotometrically examined in benzene at 20 °C. The result demonstrates that the geometry of the metallocavity is important to control both iron movement through the aromatic plane and magnitude of the Fe–I interactions.
Synthesis of Novel 5′-Hydrogenphosphonothioate Derivatives of AZT, d4T and ddI
Authors: Jin Ying , Sun Ming , Fu Hua , Zhao Yu-Fen
Published: January 2004

5′-hydrogenphosphonothioate derivatives of AZT, d4T, and ddI as anti-HIV prodrug candidates were synthesized in 61–76% yields under mild conditions through sequential one-pot reactions, i.e., couple of triethylammonium phosphinate with different alcohols in the presence of pivaloyl chloride (PV-Cl), following oxidation with elemental sulfur and further condensation with AZT, d4T, or ddI in the presence of PV-Cl.
Preparation of Silver Dendritic Nanoparticles Using Sodium Polyacrylate in Aqueous Solution
Authors: Lee Gil-Jae , Shin Seung-Il , Oh Seong-Geun
Published: January 2004

Silver dendritic nanoparticles of uniform size and morphology have been prepared at room temperature using ascorbic acid as a reducing agent and sodium polyacrylate (PAA) as a protective agent in aqueous solution.
Facile and Stable Dispersion of Carbon Nanotubes into a Hydrogel Composed of a Low Molecular-weight Gelator Bearing a Tautomeric Dye Group
Authors: Asai Masayoshi , Sugiyasu Kazunori , Fujita Norifumi , Shinkai Seiji
Published: January 2004

It was found that single-walled carbon nanotubes are stably dispersed into a low molecular-weight hydrogel (β-d-glucopyranoside–azonaphthol conjugate). From absorption and fluorescence spectral observations and microscopic images, it was shown that this gelator tends to orientate on the surface of SWNTs and specifically emits fluorescence light.
Synthesis of Pyrimidines via Base-induced Condensation of α-Chloro Oxime Derivatives
Authors: Tsuritani Takayuki , Shinokubo Hiroshi , Oshima Koichiro
Published: January 2004

A facile synthesis of 2,4,6-trisubstituted pyrimidines from the reaction of α-chloro oxime ethers with Grignard reagents has been developed. Alkyl and aryl groups can be easily introduced at the 2-position of the pyrimidine core. In addition, a synthesis of unsymmetrical pyrimidines has been examined.
Stereoselective Construction of BC-ring unit of 19-Hydroxytaxol by Samarium(II) Iodide-mediated Double Aldol Cyclization
Authors: Matsuo Jun-ichi , Ogawa Yasuyuki , Pudhom Khanitha , Mukaiyama Teruaki
Published: January 2004

The C-ring of 19-hydroxytaxol is stereoselectively constructed by samarium(II) iodide-mediated intramolecular double aldol cyclization of epoxyketo aldehyde to form the BC-ring unit which has the desired stereochemistry.
The significance of serum troponin T in patients with kidney disease: a review of the literature
Authors: Lamb Edmund J. , Webb Michelle C. , Abbas Nasir A.
Published: January 2004

The last 10 years have witnessed radical changes in the definition and diagnosis of the acute coronary syndrome (ACS), including myocardial infarction, as a result of the introduction of sensitive and specific markers of myocardial damage, the cardiac troponins. One barrier to the universal acceptance of these markers has been the observation that troponin T (cTnT) concentration is commonly increased in the presence of renal failure. Initially it was believed that this constituted an important false positive limitation of the test. This was confounded by problems with the initial cTnT assay and by the observation that troponin I (cTnI) was generally not increased in these patients. However, it has recently been demonstrated that the prognostic significance of a raised cTnT concentration in patients with a suspected ACS is unaffected by renal impairment. Further, powerful outcome studies are now being reported demonstrating that raised concentrations of serum cTnT are predictive of mortality in haemodialysis patients. This review summarizes our current understanding of the prevalence and significance of raised serum cTnT concentrations in patients with kidney disease and highlights areas where our understanding is incomplete. Evidence suggests that raised troponin concentrations in uraemic patients do indeed reflect myocardial injury. In the future, patients demonstrating this abnormality may be the target for more aggressive cardiac intervention, the advantages of which have been demonstrated in the non-uraemic population.
The emergence of type 2 diabetes in childhood
Authors: Ehtisham Sarah , Barrett Timothy G.
Published: January 2004

Type 1 diabetes (with predominant insulin deficiency) was until recently assumed to be the diagnosis of almost all children presenting with glucose intolerance. This requires insulin treatment via subcutaneous injections, and most patients develop microvascular and macrovascular complications in adulthood. Advances in genetics in the 1990s identified a group of genetic disorders of pancreatic β-cell function (maturity-onset diabetes of the young) for which the outlook is better than type 1, genetic testing is available, and oral medication is the preferred treatment. In 2000, the first cases of type 2 diabetes (predominant insulin resistance) were reported in UK children, reflecting a trend seen in North America over the last 20 years. Affected children are usually overweight or obese, often female, pubertal, predominantly of ethnic minority (South Asian) origin and have a family history of type 2 diabetes. The diagnosis is aided by demonstration of insulin resistance, and may include measurement of fasting insulin and C-peptide, markers of the metabolic syndrome (fasting lipids, sex hormone binding globulin) and absence of autoantibodies against β-cell components (e.g. glutamic acid decarboxylase). Management is aimed towards weight stabilization in the growing child, education on healthy lifestyles and the treatment of hyperglycaemia with both insulin and insulin-sensitizing agents. The underlying cause of type 2 diabetes in children is likely to be related to the epidemic of childhood obesity. There is emerging evidence of an appalling outlook for these young people in terms of miscarriages and microvascular and cardiovascular complications, which are likely to present an enormous economic and health services burden over the next 20 years.
Measurement of catecholamines and their metabolites
Authors: Peaston Robert T , Weinkove Cyril
Published: January 2004

Analysis of the low levels of catecholamines and metabolites in tissue and biological fluids has necessitated the use of highly sensitive analytical techniques. Earlier procedures utilizing radioenzymatic and immunological assays, gas chromatography or fluorimetry have generally been superseded by highly sensitive and selective chromatographic methods utilizing electrochemical or fluorimetric detection. The development of high-performance liquid chromatography (HPLC) methods for the measurement of plasma metadrenalines and the combination of HPLC with tandem mass spectrometry provides additional procedures with minimum interference from drugs and drug metabolites. This review summarizes the methodology currently available for the measurement of catecholamines and metabolites in plasma and urine, the influence of sample collection protocols and the clinical application of the methods for the biochemical detection of catecholamine-secreting tumours.
Formate buffer as preservative for urinary free catecholamine measurement
Authors: Iu Y.P. , Ho C.S. , Mak T.W.L.
Published: January 2004

Background: Strong mineral acid is the most commonly used preservative for measuring urinary free catecholamines. Leakage of corrosive acid is a safety hazard. The use of formate buffer as a safer alternative was studied.

Methods: Twenty-two urine specimens from post-operative patients were collected and preserved in 0.5 M hydrochloric acid or 0.75 M formate buffer. The specimens were stored at 4°C or -70°C, respectively. The free catecholamine content was measured at regular intervals by high-performance liquid chromatography for 6 months.

Results: The preservation capability of formate buffer was equivalent to that of hydrochloric acid. Deep-freeze storage offered additional protection independent of the preservative used.

Conclusion: The results of this study demonstrate that formate buffer, compared to the most popularly used strong mineral acid solution, is an equally effective preservation for urinary free catecholamines. The less acidic nature of formate should invite fewer unpleasant incidents and safety hazards.
A new antiglycolytic agent
Authors: le Roux C.W. , Wilkinson S.D. , Pavitt D.V. , Muller B.R. , Alaghband-Zadeh J.
Published: January 2004

Background: Glycolysis is not completely or predictably inhibited by the glucose preservative currently in use, with glucose values falling by as much as 0.5 mmol/L during a 2-4-h period after sample collection. Immediate centrifugation of all samples is also impractical and therefore misdiagnosis of disease can occur, especially if more emphasis is being placed on fasting glucose for the diagnosis of diabetes.

Methods: Glycolysis at room temperature was evaluated over time using glyceraldehyde alone as well as in conjunction with standard antiglycolytic agents.

Results: Glyceraldehyde alone does not inhibit glycolysis completely. The combination of 11mmol/L glyceraldehyde, 119 mmol/L sodium fluoride and 21.7 mmol/L potassium oxalate gave the best antiglycolytic results. The glucose values measured in samples stored at room temperature for 48 h was no different from those measured in samples centrifuged immediately after venepuncture and this is clinically superior to conventionally used sodium fluoride and potassium oxalate.

Conclusion: Plasma glucose concentrations obtained from blood collected into tubes containing glyceraldehyde, sodium fluoride and potassium oxalate will more closely reflect those of the patient at venepuncture.
The perennial problem with potassium
Authors: Trull Andrew K , Jackson Christopher , Walsh Sarah , Thornton Andi , Culank Leslie S , McHugh John
Published: January 2004

Background: The problem of spurious hyperkalaemia in blood samples delivered to hospitals from local general practitioners' (GP) surgeries remains a source of diagnostic confusion and potential danger to patients. We have carried out retrospective and prospective audits of serum potassium measurements to assess the influences of blood sample delivery time and temperature during transit from GP surgeries to a centralized laboratory on the risk of spurious serum potassium measurements.

Method: The retrospective audit included serum potassium measurements made by the pathology laboratory at Addenbrooke's Hospital on 51 843 patients attending either the hospital itself or one of 62 local GP surgeries during the months August 2001 to February 2002 (i.e. summer through to winter). The probability of spurious potassium measurements on GP patients relative to blood sample delivery time and temperature was modelled by least-squares multiple linear regression. The prospective audit included serum potassium measurements made on 40 patients presenting early in the day at the Sutton GP surgery near Ely, Cambridgeshire, during the months February to May 2002.

Results: Low blood sample delivery temperature had a greater impact on the probability of spurious potassium measurements than long delivery time. Low delivery temperature also had a greater impact on the probability of spurious hyperkalaemia than it had on the probability of spurious normokalaemia. At temperatures below 20.3°C, the probabilities of both spurious hyper- and normokalaemia for samples delivered from the most distant and closest GP surgeries to Addenbrooke's increased significantly.

Conclusions: Maintaining blood sample delivery temperatures a few degrees above 20°C will minimize the risk of spurious serum potassium measurements on samples from GP patients.
Improving the quality of information on pathology request forms
Authors: Burnett Leslie , Chesher Douglas , Mudaliar Yugan
Published: January 2004

Background: We have investigated the causes of incomplete pathology request forms received at our clinical chemistry laboratory. Based on a request form audit we found that the data most frequently missing from a pathology request form was the doctor's name, unique identification provider number, or signature.

Methods: We examined the effect of issuing the requesting doctors with self-inking stamps personalized with their name and a unique provider number.

Results: The intervention led to an immediate and sustained improvement in compliance, with the proportion of incomplete forms falling from 43% to 2%. In contrast, distribution of a memorandum alone made no significant change to the number of pathology request forms with incomplete data arriving at the laboratory.

Conclusion: This study describes a simple and low-cost solution to one of the causes of incomplete pathology request forms. It also demonstrates the effectiveness of systems improvement in health care.
Polymorphism of Trp64Arg in β3-adrenergic receptor gene among Bolivian people in rural areas at high and low altitudes
Authors: Karasaki Yuji , Kashiwazaki Hiroshi
Published: January 2004

Background: To investigate whether population differences in food and/or lifestyle could affect the distribution frequencies of polymorphism in the gene for β3-adrenergic receptor (β3-AR), the frequency of Trp64Arg polymorphism was studied among Bolivian people living in rural areas of high (about 4000 m above sea level) and low (about 300 m above sea level) altitudes.

Methods: Genomic DNA samples of Bolivian subjects (n=508) were amplified by polymerase chain reaction (PCR) for part of the β3-AR gene. The amplified PCR products were digested with restriction enzyme NciI and analysed by agarose gel electrophoresis.

Results: We found no significant difference in the frequency of Arg allele in the β3-AR gene between 331 native low-altitude Bolivian subjects (18.1%) and 177 native high-altitude Bolivian subjects (17.5%). Body mass index was not associated with Trp64Arg polymorphism among native Bolivian adults. The frequency of this allele in the complete Bolivian population (18%) was lower than that reported in Pima Indians (32%), is comparable to the Japanese (19%) and is higher than several ethnic groups, including Finns (12%) and French (4%).

Conclusions: Our data indicate that the altitude-related lifestyle of a population has had little influence on the frequency of Trp64Arg polymorphism and obesity in Bolivian natives.
Determination of the total protein and triglyceride content of human breast milk on the Synchron CX7 Delta analyser
Authors: Lynch P.L.M. , O'Kane M.J. , O'Donohoe J. , McCrea A. , Pearse J. , Wright A.
Published: January 2004

Background: Premature babies have improved clinical outcomes when fed breast milk with a relatively high protein content. Since there was no convenient way of measuring the macronutrition of breast milk we used our routine laboratory pyrogallol red dye binding method for cerebrospinal fluid microprotein (MTP) and our routine method for serum triglyceride to determine the total protein and triglyceride content of human breast milk.

Methods: The total protein contents of whole and defatted breast milk samples, randomly collected from 115 nursing mothers, analysed using a pyrogallol red dye binding assay on a Synchron CX7 Delta analyser were compared with the total protein contents determined by dry combustion analysis. Triglyceride concentrations, determined on the Synchron CX7 Delta analyser were compared with their respective creamatocrits.

Results: Passing and Bablok regression analysis (95% confidence interval) gave the following regression equations: y = 5.98(5.48 to 6.56)x-1.32(-2.02 to -0.73) where y is whole milk MTP (g/L) and x is dry combustion analysis (g/100 g); y = 7.09 (6.54 to 7.78)x-2.44 (-3.46 to -1.67) where y is volume-corrected defatted milk MTP (g/L) and x is dry combustion analysis (g/100 g); y = 7.52 (6.86 to 8.24)x+0.90(-2.42 to 3.37) where y is whole milk triglyceride (mmol/L) and x is creamatocrit (%).

Conclusion: The Synchron CX7 Delta total protein and triglyceride assays provide practical, rapid and reliable methods for the determination of the macronutrition in human milk.
An audit of biological monitoring of industrial lead workers by a UK laboratory over a 2-year period
Authors: Allen K.R. , Newton K.E.
Published: January 2004

Background: Medical surveillance of workers in the lead industry is under the statutory control of the Control of Lead at Work Act (CLAW). Over the years the CLAW regulations have been updated with a reduction in the suspension concentration for blood lead and the introduction of an action limit. As a result of these changes, an audit of blood lead measurement together with an evaluation of haemoglobin and zinc protoporphyrin (ZPP) measurements, also requested as part of surveillance, is required.

Methods: Results of measurements for blood lead, ZPP and haemoglobin in lead-exposed workers in 58 industries within the UK were collected over a 2-year period.

Results: For male workers, 8.8% of blood lead results [range 1-88 µg/dL (0.05-4.25 µmol/L), median 29 µg/dL (1.4 µmol/L), n = 3010] were above the action limit and 5.6% above the suspension limit set by CLAW. For female workers, 1.9% of blood lead results [range 1-74 µg/dL (0.05-3.58 µmol/L), median 7 µg/dL (0.34 µmol/L), n = 161] were above the action limit. No significant correlation was found between blood lead and haemoglobin in the male workers (rs =-0.04, P = 0.024) and only a slight negative correlation for the female workers (rs =-0.25, P = 0.0016). ZPP showed an exponential relationship with blood lead in the male workers with a wide scatter of results.

Conclusion: Haemoglobin and ZPP offer little towards the assessment of lead exposure in industrial workers. Blood lead in accordance with the CLAW regulations still offers the most appropriate means of industrial monitoring.
A new method of measuring the antioxidant activity of polyphenols using cumene hydroperoxide
Authors: Sugita Osamu , Ishizawa Nobuhito , Matsuto Takayuki , Okada Masahiko , Kayahara Norihiko
Published: January 2004

Background: It is well known that polyphenols lower the risk of chronic diseases such as heart disease and cancer. We describe a new method using cumene hydroperoxide (CHP) to determine the antioxidant activity of polyphenols. CHP is considered to be a model reactive lipid peroxidation product.

Methods: The method was based on two reactions: the reduction of a known concentration of CHP by polyphenols and the reaction of the remaining CHP with a methylene blue derivative (10-N-methylcarbamoyl-3,7 dimethylamino-10H-phenothiazine) in the presence of haemoglobin. Methylene blue was formed as a result of the two reactions and then measured by absorbance at 675 nm. We named this assay the 'cumene hydroperoxide/haemoglobin·methylene blue (CHP/Hb·MB) method'. We examined 13 polyphenols and nine compounds known to be antioxidants.

Results: Among the 13 polyphenols, milicetin, with the largest number of hydroxyl groups, had the highest antioxidant activity, followed by cyanidin, pelargonidin and quercetin. It is suggested that the increase in the number of hydroxyl groups induced a higher antioxidant activity. Within-run coefficients of variation were 3.6% and 3.5% at the mean antioxidant activity of 50 µmol/L and 151 µmol/L, respectively.

Conclusion: We conclude that this CHP/Hb·MB assay is capable of measuring the antioxidant activity of polyphenols.
Limitations of faecal elastase-1 and chymotrypsin as tests of exocrine pancreatic disease in adults
Authors: Brydon W.G. , Kingstone K. , Ghosh S.
Published: January 2004

Background: The faecal enzymes elastase and chymotrypsin are a relatively inexpensive non-invasive means of investigating causes of malabsorption. However, such tests may be affected by enzyme degradation or faecal dilution.

Methods: Faecal elastase-1 and chymotrypsin were measured in 225 patients in whom pancreatic disease was suspected, and the association between faecal free water and pH with these faecal enzymes was examined in subjects with normal pancreatic function.

Results: The sensitivity of faecal elastase-1 and chymotrypsin for identifying exocrine pancreatic disease was 75% and 60%, respectively. Corresponding specificities for excluding disease were 95% and 97%. The positive predictive value for faecal elastase-1 increased from 58% to 92% when watery diarrhoea was excluded. Faecal elastase-1 (inversely) and chymotrypsin (directly) were significantly associated with percentage faecal free water content in subjects without pancreatic disease. Faecal elastase-1 was not related to faecal pH, whereas chymotrypsin was inversely related to pH.

Conclusion: Faecal elastase-1 is a more sensitive test for exocrine pancreatic disease in adults but is affected by dilution in patients with watery diarrhoea. The value of faecal chymotrypsin is limited by intestinal degradation.
Long-term socio-economic impact of vestibular schwannoma for patients under observation and after surgery
Authors: Tos Tina , Caye-Thomasen Per , Stangerup Sven-Eric , Tos Mirko , Thomsen Jens
Published: January 2004

This study describes and compares the long-term socio-economic impact for patients diagnosed with a vestibular schwannoma and either operated on or observed.

A consecutive sample of patients diagnosed with vestibular schwannoma in Denmark and either operated on (748 patients) or observed by the wait-and-re-scan policy (272 patients) during the period 1976-2000 were studied retrospectively. The consequences of operation/diagnosis (andobservation) on vocational status, ability to handle daily chores and some psycho-social aspects were studied by means of a prospective postal questionnaire. Ninety-six per cent of the operated and 83 per cent of the observed patients answered the questionnaire. Overall, 34 per cent of operated patients resumed their daily activities within one to two months, and 76 per cent within four to six months. Patients operated on for a large tumour resumed their daily activities later than patients with a small tumour. Regardless of tumour size, employment was unchanged for the majority of observed and operated patients. The vocational consequences were significantly worse for operated patients with a large tumour, than for observed patients. However, no difference existed between the observed group and operated patients with a tumour below 20 mm in size. A change in vocational status was most frequent for assisting spouses, unskilled manual workers and the self-employed. The majority of both observed and operated patients experienced no change in their ability to handle daily chores. The changed ability of operated patients was worse than that of observed patients. Among various changes in their psycho-social well-being, decrease in social ability was the most frequent complaint in both groups, followed by increased fatigue, decreased concentration, increased irritability, depression and headache, decreased intellect and libido. Regardless of tumour size, the change in social ability, concentration and fatigue was worse for operatedpatients. Concerning headache, patients operated on for a large tumour were better off than observed patients and patients operated on fora small tumour. There was no difference between the operated and observed groups concerning irritability, intellect and libido.

Deterioration of vocational status, ability to handle daily chores and several aspects of psycho-social well-being are reported both by patients operated on and observed for vestibular schwannoma. However, the negative changes were more frequent among the operated patients, although the differences were surprisingly modest, especially when comparing observed patients with patients operated on for a small tumour.
Technique to prevent post-operative CSF leak in the translabyrinthine excision of vestibular schwannoma
Authors: Sanna M. , Rohit  , Skinner L. J. , Jain Y.
Published: January 2004

Cerebrospinal fluid (CSF) leak following VS removal is a challenging complication. With experience, it can be seen that anatomical factors such as the extent of pneumatization of the petrous temporal bone and posterior wall of the internal auditory canal play animportant role in contributing to CSF leak. Nevertheless, the risk of post-operative CSF leak remains a major concern for both the surgeon and patient. This paper describes a technique, which we have used since 1994, and which has helped us to achieve the lowest reported rate of post-operative CSF leak in translabyrinthine excision of vestibular schwannoma in the world literature.
Paget-Schroetter syndrome
Authors: Khan S N , Stansby G
Published: January 2004

Objective: To review current approaches to investigation and management of Paget-Schroetter syndrome (PSS).

Methods: Relevant clinical studies and reports were searched for using MEDLINE and Embase databases and cross-referenced articles. Articles were extracted using keywords by the two authors independently.

Principal findings: There is growing evidence of functional or positional anatomical defects, which lead to subtle intimal injury and a tendency for recurrence or poor outcome. Management of PSS remains controversial. Anticoagulation as a stand-alone treatment has lost favour. Active treatment with thrombolysis followed by consideration of thoracic decompression is recommended by most in the recent literature. Thrombolytic therapy appears to be a safe and efficacious method of establishing immediate patency of the axillary/subclavian vein. The timing and indications of decompression surgery are yet to be defined clearly. There are no randomized trials of treatment or management strategies in PSS.

Conclusions: Treatment of PSS remains contentious. Most authors recommend active treatment with thrombolysis followed by thoracic decompression. Multicentre randomized trials are needed.
The clinical and histological effects of Dermagraft® in the healing of chronic venous leg ulcers
Authors: Krishnamoorthy Latha , Harding Keith , Griffiths David , Moore Keith , Leaper David , Poskitt Keith , Sibbald R Gary , Brassard Alain , Dolynchuk Kenneth , Adams Julian , Whyman Mark
Published: January 2004

Objective: Pilot study to assess the safety and effectiveness of Dermagraft® when used in conjunction with multi-layer compression bandage therapy (Profore™) compared with multilayer compression only in the treatment of chronic venous leg ulcers.

Design: Open-label, prospective, multicentre, randomized, controlled clinical trial.

Methods: Patients aged at least 18 years with leg ulceration of venous aetiology were screened for inclusion in the trial. Patients with arterial disease (ankle brachial pressure index <0.7) and causes of ulceration other than venous disease were excluded. Patients were randomized into four groups. Three active treatment groups received Dermagraft® in combination with compression bandaging, Profore™: Group 1, 12 pieces of Dermagraft (one per week for 12 weeks); Group 2, four pieces of Dermagraft (Weeks 0, 1, 4, 8); Group 3, one piece of Dermagraft (Week 0). The control group was treated with compression bandaging alone (Group 4). The study was not powered to detect statistical differences in healing rates. Adverse events were reported according to national guidelines. There was no statistical analysis of adverse event data.

Results: In all 53 patients were randomized, of whom 47 completed the study per protocol. At 12 weeks complete healing of the ulcer, analysed by 'intention-to-treat' (ITT) was 15% using Profore alone, 7% using single application Dermagraft and Profore (Group 3), compared with 38% using multiple applications of Dermagraft and Profore (Groups 1 and 2). At study discontinuation, the median percentage reduction in wound area was 81.4% for Group 1, 88.6% for Group 2, 59.4% for Group 3 and 78.1% for Group 4. No major safety issues were identified during the course of the study.

Conclusions: The results of the pilot study indicate that four pieces of Dermagraft are the optimal application frequency to take forward to further clinical trials. Further studies are required to confirm these data, and these should be powered to detect whether there are statistical differences in healing rates and safety between different regimens.
Role of ambulatory venous pressure measurement in the assessment of venous disease
Authors: Dix F P , McCollum C N
Published: January 2004

Objectives: The gold standard assessment of venous hypertension is ambulatory venous pressure (AVP). Aims of this study were to determine the relationship of AVP with clinical severity of venous disease and whether AVP accurately identifies sites of incompetence.

Methods: 117 limbs (93 subjects) underwent classification of venous signs, duplex imaging and AVP measurement. Eleven limbs had no disease, 28 had varicose veins (VVs), 45 had chronic venous insufficiency, 15 had healed ulceration, and 18 had active ulceration.

Results: Mean (standard error of the mean) pressure relief index (PRI) showed a step-wise decrease from 1794 (±317) in controls to 167 (±46) in active ulcers ( P <0.001, ANOVA). PRI correlated with clinical severity of venous disease (r = -0.60, P <0.01, Pearson). Superficial reflux alone was most common in VVs (60%), deep reflux in active ulceration (11%) and combined reflux in healed ulceration (93%). Tourniquet tests showed an increase in PRI only in combined reflux ( P <0.028, ANOVA).

Conclusions: AVP correlates with skin condition but is inaccurate in identifying sites of incompetence.
Subfascial endoscopic perforator surgery using a soft trocar for varicose veins in the lower leg
Authors: Hirokawa Masayuki , Inoue Yoshinori , Iwai Takehisa
Published: January 2004

Objective: To describe the use of a novel soft trocar to perform subfascial endoscopic perforator surgery (SEPS) in patients with varicose veins in the lower leg.

Procedures: From January 1999 through March 2001, SEPS was performed in 14 patients (17 legs) with primary varicose veins (clinical classes 3-6) by using a soft trocar. The soft trocar is a Y-shaped polyvinyl chloride bag with two ports at one end and a flexible, sealing ring at the opposite end. The subfascial space was dissected with an endoscopic dissection cannula and expanded with a balloon. Carbon dioxide gas insufflation was applied, and the perforating veins were divided by using UltraShears inserted simultaneously with an endoscope through the second port of the trocar.

Results: A mean of 4.7 ± 2.9 perforating veins per leg were divided. No wound complications occurred.

Conclusion: Use of the soft trocar facilitates both visualization and manipulation during SEPS.
A comparison of health-related quality of life of patients with primary and recurrent varicose veins
Authors: Beresford T , Smith J J , Brown L , Greenhalgh R M , Davies A H
Published: January 2004

Aim: To determine whether recurrent varicose veins affect patient quality of life. The health-related quality of life (HRQL) scores of patients with recurrent varicose veins were compared with those of patients presenting with primary varicose vein disease.

Methods: HRQL among patients attending outpatient appointments for recurrent and primary varicose veins was measured using the Aberdeen Varicose Vein Questionnaire (AVVQ) and the Short Form-36 General Health Survey (SF-36).

Results: Questionnaires were given to 211 patients (150 primary, 61 recurrent), and 194 (133 primary, 61 recurrent) completed them. For the AVVQ, patients with recurrent varicose veins had significantly worse symptom scores compared with those with primary disease (24.87 ± 12.28 vs 17.77 ± 9.68, Mann-Whitney, P <0.01). The SF-36 recorded significantly worse HRQL (Mann-Whitney, P <0.05) for patients with recurrent varicose veins compared with those with primary varicose veins in all but one of the eight domains (role limitation attributed to emotional problems, RE, P = 0.073).

Conclusion: Varicose vein recurrence is associated with a significantly worse HRQL than is found among patients with primary varicose veins.
Updated laser approaches to the management of cosmetic leg veins
Authors: Sadick Neil S
Published: January 2004

The utilization of lasers and intense pulsed light sources is playing an increasing role in the management of cosmetic lower extremity venous ectasias. The advent of long-wavelength technologies in conjunction with variable pulse durations, spot sizes and the capabilities of the technologies to deliver high fluences has made the treatment of small non-cannulizable vessels <1 mm as well as larger veins up to 3 mm in diameter an efficient therapeutic modality in this setting. The monomodal approach for the treatment of such vessels is outlined in this review.
Compression sclerotherapy of anterolateral thigh primary varicose veins (lateral accessory saphenous varicose veins): a prospective five-year follow-up study
Authors: Jagtman B A , Tazelaar D J , De Leeuw J
Published: January 2004

Aim: To determine the percentage of varicose vein recurrence after compression sclerotherapy of a specific primary varicose vein, the anterolateral thigh vein (lateral accessory saphenous vein), without saphenofemoral junction (SFJ) incompetence at yearly intervals in a long-term follow-up study, and to investigate factors influencing recurrence.

Patients and methods: Of 117 patients recruited, 11 were lost to follow up; therefore 106 patients were evaluated: 97 women, mean age 42 years (range 21-72) and nine men, mean age 47 years (range 21-67). If SFJ incompetence was present, surgical ligation of the junction was performed. Primary varicose veins were treated with compression sclerotherapy using polidocanol. A total of 111 limbs were studied.

Results: Recurrent varicose veins were found after six months in 6% of cases, after one year in 18% (cumulative percentage), after two years in 28%, after three years in 36%, after four years in 46%and after five years in 54%. No differences could be detected between the recurrence group and the group without recurrence regarding length of varicose veins, amount of polidocanol used, number of injections, circumference of the leg or age of the patient. The varicose vein diameter was significantly larger in the recurrence group.

Conclusions: Compression sclerotherapy with polidocanol of the anterolateral thigh vein (lateral accessory saphenous vein) without SFJ incompetence results in a high recurrence rate. Recurrence depends only on the vessel diameter, and not on the length of the varicose vein, amount of sclerosant used or patient age.
Calf exercise in the seated position using a new dynamic biped device increases femoral vein peak velocity up to eight-fold
Authors: Caruana M F , Brightwell R E , Huguet E L , Whitear P , Hodgkinson D W , Osman I S
Published: January 2004

Background and objective: Lower limb deep venous thrombosis is a common condition with a recognized morbidity and mortality. Hitherto known as a complication in hospitalized patients, anecdotal media reports and scientific trials have raised the profile of the same condition in association with air travel. Although probably multifactorial in aetiology, venous stasis is considered an important and correctable risk factor in the pathogenesis of deep venous thrombosis. The aim of this study was to assess the effectiveness of exercising the calf muscle blood pump in increasing venous blood flow using a new dynamic alternating inflatable biped device (Lymgym™, Lymgym Ltd, UK) which has been designed to be used by air passengers.

Methods: Doppler ultrasound was used to assess peak flow velocity in the superficial femoral vein in 30 lower limbs of 15 healthy volunteers with no history of venous disease. Measurements of peak flow velocity were taken at rest in the seated 'coach position' and during calf muscle pump exercises with the device.

Results: Peak blood flow velocity was eight-fold higher ( P < 0.0001, Wilcoxon signed rank test) during exercise with the device than at rest.

Conclusions: These results show that use of the dynamic alternating biped device (Lymgym™) effectively reduces venous stasis when used in the seated position as defined by measurements of peak venous blood flow. These results provide the scientific justification for further studies assessing the value of this device in reducing the risk of travel-related thrombosis.
Symptoms, clinical disability scores and reflux in complicated and uncomplicated primary varicose veins
Authors: Saarinen J , Heikkinen M , Suominen V , Virkkunen J , Zeitlin R , Rasku K , Saaristo R , Vainio J , Nordback I , Salenius J-P
Published: January 2004

Objective: To evaluate the role of subjective symptoms, grade of disability and axial reflux in superficial veins in different clinical stages of varicose veins (VVs).

Methods: A total of 172 legs with primary venous insufficiency from 126 patients were studied. The examination involved evaluation of the CEAP clinical class and clinical disability score (CDS), recording of any symptoms of varicose disease, and a hand-held Doppler (HHD) examination of the superficial veins. Colour-flow duplex imaging (CFDI) was also performed in 22% of the legs.

Results: The rate of insufficiency of the great saphenous vein (GSV) was 83% in complicated legs (C4-6), and 68% in uncomplicated legs (C2-3), ( P > 0.05). There was a difference between complicated and uncomplicated legs in the insufficiency of the whole GSV [C4-6: n = 18 (39%) versus C2-3: n = 12 (12%), P < 0.005]. Sensation of pain was noted in 68% of the legs in class C1, 60% of those in class C2-3 and 81% of those in class C4-6. Sensation of oedema was recorded in 70% of the legs in class C1, 65% of those in class C2-3 and 86% of those in class C4-6, respectively. CDS classes 2-3 were significantly more frequent among complicated legs (C4-6: 54% versus C2-3 12%, P < 0.005).

Conclusions: Leg symptoms are frequent throughout classes C1-6. Their clinical usefulness is therefore limited. CDS parallels well with the clinical classification. In complicated disease the whole saphenous vein is more frequently insufficient.
Inflammation parallels severity of chronic venous insufficiency
Authors: Labropoulos N , Leder D M , Kang S S , Mansour M A , Baker W H
Published: January 2004

Objective: This study was designed to assess the haemodynamic flow changes in patients with chronic venous insufficiency (CVI).

Methods: Duplex scanning was used to evaluate prospectively the flow characteristics in the lower limb circulation and the number of enlarged lymph nodes in the groin of normal subjects, patients with CVI classes 2, 4, 5 and 6, and patients with acute cellulitis. Phasicity and continuous flow patterns were assessed in the venous system, while the arterial system was evaluated for tri-phasic flow, absence of flow reversal and absence of flow reversal with hyperaemic flow (increased peak systolic and end diastolic velocities). Additionally, the number and size of the groin lymph nodes around the saphenofemoral junction were recorded.

Results: Patients with more severe class 4-6 CVI demonstrated an increased prevalence of abnormal flow patterns within the venous system of the leg compared to the normal phasic flow pattern seen in the absence of disease ( P < 0.001). Within the arterial system, significant changes were also observed in all three arteries studied in the legs of patients with class 4-6 CVI ( P < 0.001). For both the arterial and venous systems, no difference was noted between control limbs vs class 2 diseases or class 4-6 diseases vs cellulitis. With respect to the evaluation of inguinal lymph nodes, patients with class 2 disease were approximately four times as likely to have positive lymph nodes, and patients with more severe CVI were approximately 13 times as likely to have significant lymph nodes present.

Conclusions: This study demonstrated that patients with more advanced stages of CVI had arterial and venous flow increases similar to those seen in an acute inflammatory condition such as cellulitis. These changes were most pronounced in the perforating and subcutaneous vessels in the leg.