bluuebunny/crossref_metadata_2025 huggingface dataset:
Compound heterozygosity of two missense mutations in the NADH‐cytochrome b5 reductase gene of a Polish patient with type I recessive congenital methaemoglobinaemia
Authors: Grabowska Dorota , Plochocka Danuta , Jablonska‐Skwiecinska Ewa , Chelstowska Anna , Lewandowska Irmina , Staniszewska Krystyna , Majewska Zofia , Witos Iwona , Burzynska Beata
Published: May 2003

A case of type I methaemoglobinaemia observed in a Polish subject with compound heterozygosity for two mutations in the reduced nicotinamide adenine dinucleotide (NADH) cytochrome b5 reductase (b5R) gene is described. One is a novel mutation 647T→C which leads to substitution of isoleucine by threonine at position 215 (I215T). This maternal mutation was found in several family members. A previously known mutation, 757G→A, leads to the replacement of valine by methionine at position 252 (V252M). The latter mutation was found also in the father and one of the two brothers. The effects of these mutations were analysed on a model of the human b5R protein obtained by homology modelling. Although both amino acid substitutions are located in the NADH‐binding domain, the whole protein structure, especially the region between the flavin adenine dinucleotide and NADH‐binding domains, is disturbed. The structural changes in the I215T mutant are less prominent than those in the V252M mutant. We presume that the 647T→C mutation is a type I mutation, however, it has not been observed in the homozygous state.
TYRP1 is associated with dun coat colour in Dexter cattle or how now brown cow?
Authors: Berryere T. G. , Schmutz S. M. , Schimpf R. J. , Cowan C. M. , Potter J.
Published: May 2003

Tyrosinase related protein 1 (TYRP1), which is involved in the coat colour pathway, was mapped to BTA8 between microsatellites BL1080 and BM4006, using a microsatellite in intron 5 of TYRP1. The complete coding sequence of bovine TYRP1 was determined from cDNA derived from skin biopsies of cattle with various colours. Sequence data from exons 2–8 from cattle with diluted phenotypes was compared with that from non‐diluted phenotypes. In addition, full‐sib families of beef cattle generated by embryo transfer and half‐sib families from traditional matings in which coat colour was segregating were used to correlate TYRP1 sequence variants with dilute coat colours. Two non‐conservative amino acid changes were detected in Simmental, Charolais and Galloway cattle but these polymorphisms were not associated with diluted shades of black or red, nor with the dun coat colour of Galloway cattle or the taupe brown colour of Braunvieh and Brown Swiss cattle. However, in Dexter cattle all 25 cattle with a dun brown coat colour were homozygous for a H424Y change. One Dexter that was also homozygous Y434 was red because of an ‘E+/E+’ genotype at MC1R which lead to the production of only phaeomelanin. None of the 70 remaining black or red Dexter cattle were homozygous for Y434. This tyrosine mutation was not found in any of the 121 cattle of other breeds that were examined.
Isolation and analysis of the non‐hydrolysable fraction of a forest soil and an arable soil (Lacadée, southwest France)
Authors: Poirier N. , Derenne S. , Balesdent J. , Mariotti A. , Massiot D. , Largeau C.
Published: May 2003

Recent studies have pointed to the occurrence in soil organic matter of an insoluble macromolecular fraction, resistant to drastic alkali and acid hydrolysis. This non‐hydrolysable fraction may contribute to the stable carbon pool in the soil and thus be important for the global carbon budget. We have developed a method to isolate such chemically resistant components, whilst ensuring complete elimination of the hydrolysable constituents of the organic matter but avoiding the formation of insoluble compounds via Maillard‐type condensation reactions. Maize leaves, material especially susceptible to artefact formation, were used for this optimization. Several of the treatments that we tested, including the Klason lignin protocol, proved unsuitable. The most suitable protocol, by progressive hydrolysis with trifluoroacetic and hydrochloric acid, revealed a non‐hydrolysable fraction in maize leaves accounting for about 5% by weight of the leaves and corresponding chiefly to lignin and condensed tannins. The protocol was applied to a forest soil and to the soil from an adjacent plot cleared 35 years ago and since cropped continuously with maize. The abundance, chemical composition and sources of the non‐hydrolysable fraction of these two soils were determined by a combination of spectroscopy, pyrolysis and electron microscopy. This fraction accounted for about 6% of the total organic carbon of both soils; it contains aliphatic moieties, black carbon, melanoidins and, we think, condensed tannins.
Toxic effect of cadmium and nickel on soil enzymes and the influence of adding sewage sludge
Authors: Moreno J. L. , García C. , Hernández T.
Published: May 2003

Sewage sludge is increasingly used as an organic amendment to soil, especially to soil containing little organic matter. However, little is known about the utility of this organic amendment in the reclamation of soil polluted with heavy metals. We studied the effects of adding sewage sludge on enzymatic activities of a semi‐arid soil contaminated with Cd or Ni in the laboratory. The activities of urease, phosphatase, β‐glucosidase and protease‐BAA were measured in soil containing concentrations of Cd or Ni in the range 0–8000 mg kg−1 soil, and their inhibition was compared with those of the enzymatic activities in the same soil amended with sewage sludge and containing similar concentrations of the heavy metals. The inhibition was tested for three different incubation times to determine changes in the effect of the heavy metals on hydrolase activity with the time elapsed after contamination. Ecological dose (ED) values of Cd and Ni were calculated from three mathematical models which described the inhibition of the enzymatic activities with increasing concentrations of heavy metal in the soil. For urease and phosphatase activities, the ED values for Cd and Ni increased after application of sewage sludge to soil, indicating a decrease in Cd and Ni toxicity. The other two enzymes (β‐glucosidase and protease‐BAA) were less sensitive to Cd or Ni contamination, and it was more difficult to determine whether addition of sewage sludge had affected the inhibition of these enzymes by the heavy metals.
Toxicity factors in acidic forest soils: attempts to evaluate separately the toxic effects of excessive Al3+ and H+ and insufficient Ca2+ and Mg2+ upon root elongation
Authors: Kinraide T. B.
Published: May 2003

The acidic soils of temperate forests and some pastures on former forest land characteristically contain large amounts of aluminium and hydrogen ions and small amounts of calcium and magnesium ions. The relative importance of these potential toxicity factors are assessed from published data from soils collected in the United States and Europe. Activities of ions in the soil solutions and at the surfaces of root‐cell plasma membranes were computed with electrostatic models. Activities of Al3+ in soil solutions ({Al3+}) peaked at pH 4.1, and Al3+ activities at the surface of the plasma membrane ({Al3+}0) achieved a broad maximum between pH 4.1 and 4.8; thus, Al3+ intoxication is likely to be more severe in soils at pH 4.1 than in more acidic ones. Intoxication (assessed by root elongation) correlated somewhat ambiguously with ion activities, but Al3+‐ and H+‐induced depletion of Ca2+ and Mg2+, or both, from the cell surface appears to play a role in toxicity. By contrast, experiments in solution culture, where intercorrelation among {Al3+}, {H+}, and {Ca2+} could be avoided, clearly demonstrated the following extrinsic and intrinsic effects.

1 The ions Al3+ and H+ are intrinsic toxicants.

2 They are also extrinsic toxicants because of the electrostatic displacement of Ca2+ from the surface of the plasma membrane.

3 They are extrinsic ameliorants because each electrostatically displaces the other from the surface of the plasma membrane.

4 The ion Ca2+ is an extrinsic ameliorant because of the electrostatic displacement of Al3+ and H+ from the surface of the plasma membrane.

5 It is an intrinsic ameliorant of intrinsic H+ toxicity, but not intrinsic Al3+ toxicity.

6 It meets an intrinsic requirement.

7 The ion Mg2+ resembles Ca2+ in item 4 but not items 5 and 6 in short‐term cultures.

In acidic soils, Al3+ may prevent H+ from becoming an intrinsic toxicant (item 3) and may induce an insufficiency of Ca2+ and Mg2+ (item 2). These findings have implications for the mechanisms by which woodland plants tolerate very acidic soils.
Low allozyme variation in snapper, Pagrus auratus, in Victoria, Australia
Authors: Meggs L. B. , Austin C. M. , Coutin P. C.
Published: May 2003

The population genetic structure of snapper, Pagrus auratus (Bloch and Schneider), in Victoria was investigated using six polymorphic allozyme loci. Fish were sampled from four sites in Victoria and single locations in South Australia, Western Australia and New Zealand. Although there were distinct genetic differences between the snapper populations from each of the Australian states and New Zealand, only minor and largely insignificant differences were detected among Victorian populations. The results are consistent with previous genetic and tagging studies that indicate no mixing between snapper stocks in Victoria and Spencer Gulf in South Australia. This justifies separate management of the snapper fisheries in these regions. The low levels of polymorphism and heterozygosity in Victorian snapper suggest an isolation by distance model of population structure rather than one of discrete subpopulations.
An examination of the salmon aquaculture conflict in British Columbia using the graph model for conflict resolution
Authors: Noakes D. J. , Fang L. , Hipel K. W. , Kilgour D. M.
Published: May 2003

In 1995, the British Columbia Government imposed a moratorium on salmon farming expansion and conducted an environmental assessment review of the industry. Despite the generally favourable conclusions of this review, the government delayed making a decision on the future of the industry for more than 2 years. This issue is examined using a graph model for conflict resolution. The graph model requires only ordinal preferences for the decision‐makers and allows the analyst to impose realistic constraints on the conflict such as providing for unidirectional and common moves. Given the preferences of the players involved in the conflict, inaction on the part of the provincial government was a stable solution for 2 years. The deteriorating economic situation in British Columbia combined with an improved public acceptance of the salmon farming industry shifted the solution to one of adopting the recommendations from the environmental assessment review and eventually lifting the moratorium.
Mechanism of smoke‐induced seed germination in a post‐fire chaparral annual
Authors: Keeley J.E. , Fotheringham C.J.
Published: May 2003

1  Smoke‐stimulated germination in the post‐fire flora of California chaparral does not appear to be triggered by nitrate. Application of freshly prepared unbuffered KNO3 solutions (pH c. 6.2) failed to enhance germination of five populations of Emmenanthe penduliflora or one Phacelia grandiflora population, regardless of light or stratification conditions.

2  KNO3 buffered at acidic pH (or unbuffered solutions equilibrated with atmospheric CO2) did induce germination, but KNO3 solutions at pH 7 failed to induce germination. Induction of germination is therefore not due to the nitrate ion per se, but rather to high [H+], although buffered controls gave weak germination at low pH, suggesting a role for H+ plus nitrate. However, other anions such as sulphate were equally as effective as nitrate at breaking dormancy.

3  The germination response to KNO3 was affected by the type of filter paper used and this may be linked to differences in pH.

4  NO2, at concentrations present in biomass smoke, was highly effective at inducing germination, and other oxidizing agents also induced germination.

5  Several growth regulators, including nitrite and gibberellin, were stimulatory only at acidic pH, but KCN was stimulatory across a broad pH range.

6  Germination decreased at smoke exposures longer than a few minutes. Also, smoked water samples effective at breaking dormancy were acidic and were less effective when buffered to pH >7.

7  Physical scarification of the seed coat induced germination but the effect was not due to penetration of a water barrier, or to enhanced oxygen uptake or to wound responses such as CO2 or ethylene production.

8  Different effects of the gibberellin inhibitor CCC (chlorocholine chloride) suggested that the mechanisms of scarification‐induced and smoke‐induced germination may differ.

9  We conclude that either oxidizing gases in smoke and/or acids generated on burnt sites play a role in germination of post‐fire annuals in chaparral.
Population growth and viability analyses of the clonal woodland herb, Asarum canadense
Authors: Damman Hans , Cain Michael L.
Published: May 2003

1  Long‐term demographic field studies combined with simulation models that incorporated two types of stochasticity were used to investigate the relative impact of reproduction and survival on the persistence of populations of the North American woodland herb, Asarum canadense.

2  Field data were collected over 7 years in replicate plots located in early and late successional forest habitat. By following marked ramets from year to year it proved possible to investigate the demography both of ramets and of groups of genetically identical ramets (clones).

3  
A. canadense exhibited considerable temporal and spatial variation in reproductive success, survivorship, and population growth rates. Populations of ramets and clones in late successional forest habitats held their own, while those in early successional forest habitats declined.

4  Sexual and clonal reproduction had less impact on population growth than did survival. Nonetheless, seedling recruitment was important, as indicated by the relatively high rates of genet turnover in A. canadense populations.

5  Results from simulations indicated that the vast majority of genets in both habitat types failed to reproduce. Over their lifetime, simulated genets produced a maximum of 44 and 77 seedlings in early and late successional forest habitat, respectively.

6  Although A. canadense genets are potentially immortal, the maximum life span for 2000 simulated genets was 104 years. Simulated genets lived a mean of 3.0 and 4.8 years in early and late successional forest habitat, respectively.

7  Simulated A. canadense populations only persisted in late successional forest habitat. Within simulated late successional forest populations, the number of ramets tended to decrease over time, while the number of genets tended to increase over time.

8  The minimum viable population size for A. canadense ramets in late successional forest was 25 individuals with environmental stochasticity only, and 1000 individuals with both environmental and demographic stochasticity; for genets in late successional forest, the corresponding numbers were 20 and 25, respectively.

9  Ramet and genet dynamics differed greatly in A. canadense, highlighting the importance of long‐term demographic studies at each of these levels.
Evolving patterns of tobacco use in northern Sweden
Authors: Rodu B. , Stegmayr B. , Nasic S. , Cole P. , Asplund K.
Published: May 2003

Abstract.  Rodu B, Stegmayr B, Nasic S, Cole P, Asplund K (University of Alabama at Birmingham, Birmingham, AL, USA; Umeå Hospital, Umeå, Sweden). Evolving patterns of tobacco use in northern Sweden. J Intern Med 2003; 253: 660–665.

Background and objectives.  Cross‐sectional data from northern Sweden suggest that the increased use of Swedish moist snuff (snus) may have contributed to a decline in the prevalence of smoking, especially amongst men. This study describes the evolving patterns of tobacco use in this population over the period 1986–1999.

Design.  This is a prospective follow‐up study of 1651 men and 1756 women, aged 25–64 years, who were enrolled in the northern Sweden MONICA project (entry in 1986, 1990, 1994) and who were followed‐up in 1999. Information on tobacco use at entry and at follow‐up was used to describe the stability of tobacco use over a period of 5–13 years ending in 1999.

Results.  Snus was the most stable form of tobacco use amongst men (75%); only 2% of users switched to cigarettes and 20% quit tobacco altogether. Smoking was less stable (54%); 27% of smokers were tobacco‐free and 12% used snus at follow‐up. Combined use (smoking and snus) was the least stable (39%), as 43% switched to snus and 6% switched to cigarettes. Former users of both products were much less stable than former users of either cigarettes or snus. The stability of smoking amongst women was 69%, which was higher than that amongst men (P < 0.05).

Conclusions.  The use of snus played a major role in the decline of smoking rates amongst men in northern Sweden. The evolution from smoking to snus use occurred in the absence of a specific public health policy encouraging such a transition and probably resulted from historical and societal influences.
Cell signalling and gene expression mediated by RET tyrosine kinase
Authors: Kurokawa K , Kawai K. , Hashimoto M. , Ito Y. , Takahashi M.
Published: May 2003

Abstract.  Kurokawa K, Kawai K, Hashimoto M, Ito Y, Takahashi M (Nagoya University Graduate School of Medicine, Showa‐ku, Nagoya, Japan). Cell signalling and gene expression mediated by RET tyrosine kinase (Minisymposium). J Intern Med 2003; 253: 627–633.

Germline mutations of the RET proto‐oncogene cause multiple endocrine neoplasia (MEN) 2A or 2B by different mechanisms. As is the case for other receptor tyrosine kinases, mutant RET recruits a variety of signalling molecules via phosphorylated tyrosine residues present in the kinase domain and carboxy‐terminal tail. As we previously reported, the signaling via phosphorylated tyrosine 1062 plays a crucial role in the transforming activities of both RET‐MEN2A and RET‐MEN2B mutant protein. Interestingly, this single tyrosine residue represents a binding site for several signalling molecules including SHC, Enigma, SNT/FRS2, DOK and IRS1 and is responsible for activation of the RAS/ERK, PI3‐K/AKT, JNK, p38MAPK and ERK5 signalling pathways. Amongst these, the PI3‐K/AKT and JNK pathways appeared to be more strongly activated in the cells expressing RET‐MEN2B than in the cells expressing RET‐MEN2A, suggesting the possibility that these pathways may be involved in the disease phenotype. In addition, RET is alternatively spliced to produce three isoforms and the splicing site is present just downstream of tyrosine 1062. These isoforms play different roles for the tumour development associated with MEN 2 or the development of the kidney and the enteric nervous system. Moreover, using differential display analysis, we identified several genes whose expression is highly induced by RET‐MEN2B mutant proteins. The differential gene expression by RET‐MEN2A and RET‐MEN2B may also be important for the development of their phenotypes.
Continuous measurement of caffeine and two metabolites in blood and skeletal muscle of unrestrained adult horses by semi‐automated in vivo microdialysis
Authors: Chou C.‐C. , Webb A. I. , Brown M. P. , Gronwall R. R. , Vickroy T. W.
Published: May 2003

Concentrations of caffeine (CA) and two metabolites were measured simultaneously in venous blood and splenius muscle of adult horses using a semi‐automated in vivo microdialysis sampling technique. Dialysates from muscle and jugular vein were collected continuously for 48 h and drug levels were determined by high performance liquid chromatography (HPLC). Following i.v. injection, CA (3 mg/kg) attained a peak blood level of nearly 5400 ± 600 ng/mL and decreased with a half‐life of 15.3 ± 0.7 h. Pharmacokinetic and statistical comparisons between CA concentrations in jugular dialysates and plasma samples revealed no significant differences between these sampling techniques. However, measurements in muscle and blood revealed unexpected pharmacokinetic differences, including significantly elevated concentrations of CA in muscle for 4 h following drug administration. In contrast, the CA metabolites theophylline (TP) and theobromine (TB) exhibited delayed appearances in muscle and blood with peak concentrations of 300 ± 60 ng/mL (TP) and 150 ± 50 ng/mL (TB) detected in both tissues 1 day following CA administration. This study demonstrates that our novel semi‐automated microdialysis procedure for continuous monitoring of drug and metabolite levels may be useful for related studies in other domesticated large animal species.
Levamisole mucosal adjuvant activity for a live attenuatedEscherichia colioral vaccine in weaned pigs
Authors: Božić F. , Bilić V. , Valpotić I.
Published: May 2003

The present study tested the hypothesis that levamisole exerts its immunopotentiating activity in weaned pigs vaccinated against colibacillosis by priming the lymphocytes and macrophages in the mesenteric lymph node (MLN). Ten weaned piglets were used and allocated into two equal groups. The experimental group was intramuscularly primed with levamisole at an immunostimulatory dose of 2.5 mg/kg given daily, in three consecutive days, and controls received saline according to the same schedule. Both groups were orally vaccinated with the vaccinalEscherichia colistrain on day 0 and challenged with the virulentE. colistrain 7 days later. All pigs were killed on postchallenge day 6. Upon virulent challenge the health status of the two groups was evaluated by clinical observations, and expression of CD25, SWC7 and SWC9 activation antigens by MLN and spleen T and B cells and macrophages, respectively, was tested using flow cytometry. Priming by levamisole significantly contributed to the effectiveness of a live attenuated oral vaccine against porcine postweaning colibacillosis, as evidenced by a good health status of primed vaccinated vs. un‐primed vaccinated pigs. The CD3+, CD25+and SWC9+MLN but not spleen T cells and macrophages increased in experimental vs. control pigs, implying that levamisole exerts its potentiating activity in the MLN by augmenting both recruitment and activation of cells that participate in cell‐mediated immunity.
A comparison of propofol infusion and propofol/isoflurane anaesthesia in dexmedetomidine premedicated dogs
Authors: Kuusela E. , Vainio O. , Short C. E. , Leppäluoto J. , Huttunen P. , Ström S. , Huju V. , Valtonen A. , Raekallio M.
Published: May 2003

The effects of propofol infusion were compared with propofol/isoflurane anaesthesia in six beagles premedicated with 10 μg/kg intramuscular (i.m.) dexmedetomidine. The suitability of a cold pressor test (CPT) as a stress stimulus in dogs was also studied. Each dog received isoflurane (end tidal 1.0%, induction with propofol) with and without CPT; propofol (200 μg/kg/min, induction with propofol) with and without CPT; premedication alone with and without CPT in a randomized block study in six separate sessions. Heart rate and arterial blood pressures and gases were monitored. Plasma catecholamine, beta‐endorphin and cortisol concentrations were measured. Recovery profile was observed. Blood pressures stayed within normal reference range but the dogs were bradycardic (mean heart rate < 70 bpm). PaCO2 concentration during anaesthesia was higher in the propofol group (mean > 57 mmHg) when compared with isoflurane (mean < 52 mmHg). Recovery times were longer with propofol than when compared with the other treatments. The mean extubation times were 8 ± 3.4 and 23 ± 6.3 min after propofol/isoflurane and propofol anaesthesia, respectively. The endocrine stress response was similar in all treatments except for lower adrenaline level after propofol infusion at the end of the recovery period. Cold pressor test produced variable responses and was not a reliable stress stimulus in the present study. Propofol/isoflurane anaesthesia was considered more useful than propofol infusion because of milder degree of respiratory depression and faster recovery.
Efficacy of intramammary treatment with procaine penicillin G vs. procaine penicillin G plus neomycin in bovine clinical mastitis caused by penicillin‐susceptible, gram‐positive bacteria – a double blind field study
Authors: Taponen S. , Dredge K. , Henriksson B. , Pyyhtiä A.‐M. , Suojala L. , Junni R. , Heinonen K. , Pyörälä S.
Published: May 2003

The efficacy of intramammary treatments containing procaine penicillin G alone (treatment A) or a combination of procaine penicillin G and neomycin (treatment B) was compared in treating clinical bovine mastitis caused by gram‐positive bacteria susceptible in vitro to penicillin G. Both treatments were supplemented with a single intramuscular injection of procaine penicillin G on the first day of treatment. The study was carried out using a double blind design on commercial dairy farms in Southern Finland. A total of 56 quarters were treated with treatment A and 61 with treatment B. The cure rates for both treatments were equal, which suggests that the use of the penicillin G–aminoglycoside combination does not increase the efficacy of the treatment over that achieved by using penicillin G alone in bovine clinical mastitis caused by penicillin‐susceptible, gram‐positive bacteria.
Automated Plasmapheresis Compared with other Plasma Collection Methods in the Horse
Authors: Feige K. , Ehrat F. B. , Kästner S. B. R. , Schwarzwald C. C.
Published: May 2003

SummaryThe purpose of this study was to evaluate plasmapheresis as a method for plasma extraction in comparison with centrifugation or gravity sedimentation. The study was designed as a cross over trial with six Freiberger horses undergoing plasma donation by plasmapheresis followed by whole‐blood donation and subsequent plasma production 4 weeks later. Automated plasmapheresis and whole‐blood donation were well tolerated in all horses. The plasmapheresis method achieved an almost complete removal of erythrocytes and leucocytes from plasma at all flow rates. After blood bag centrifugation, significantly more erythrocytes (P < 0.01) and leucocytes (P < 0.01) were present in the prepared plasma compared with plasmapheresis plasma. Plasma prepared by gravity sedimentation contained significantly more erythrocytes and leucocytes than plasma prepared with the other techniques (P < 0.01), and platelet aggregation was observed. The coagulation proteins and the total protein content of plasma prepared after plasmapheresis and blood bag centrifugation did not differ significantly from values measured prior to collection (P > 0.05). However, the activity of factor VIII was significantly lower 24 h after gravity sedimentation of blood than activity prior to blood collection (P < 0.01). In conclusion, automated plasmapheresis is the method of choice for the production of high quality equine plasma.
Maternal and Infant Services: Examination of access in a culturally diverse community
Authors: Comino EJ , Harris E
Published: May 2003

Objectives:  The aim of this study was to evaluate access of resident immigrant families from a non‐English speaking background to Maternal and Infant Services operated by Community Health Services in south‐western Sydney.

Methods:  An ecological study compared the demographic characteristics of mothers with an infant aged less than 12 months in three separate data collections. These were a 3‐month Community‐based Health Services Census, the 1996 Midwives Data Collection and the ABS 1996 Census of Population and Housing.

Results:  Information was collected from 2048 infants and their families who were newly registered with Maternal and Infant Services. Approximately 75% of newborn infants were registered with services. Women who were born in a non‐English‐speaking country were over‐represented in the data. For both overseas and Australian‐born women those who left school aged less than 17 years were under‐represented compared with analysis of the related data systems.

Conclusions:  The data suggest that migrant women from non‐English‐speaking backgrounds are accessing Maternal and Infant Services. However, innovative approaches for service delivery are indicated for women who may be considered socially disadvantaged, irrespective of their ethnic or cultural backgrounds.
Adherence to antiretroviral therapy: are we doing enough?
Authors: Read T. , Mijch A. , Fairley C. K.
Published: May 2003

Adherence to antiretroviral therapy is a powerful predictor of response to therapy. For optimal antiretroviral therapy response, individuals need to take more than 95% of their prescribed medication. The most widely used method for measuring adherence is self‐report of the number of missed doses and this should be done at every clinic visit. There are several well‐recognized predictors of poor adherence, such as illicit drug use, depression, limited knowledge or ambivalence about starting treatment. Adherence can be improved by addressing these issues or through other means such as pill boxes or electronic reminders. (Intern Med J 2003; 33: 254−256)
Scleroderma renal crisis: poor outcome despite aggressive antihypertensive treatment
Authors: Walker J. G. , Ahern M. J. , Smith M. D. , Coleman M. , Pile K. , Rischmueller M. , Cleland L. , Roberts‐Thomson P. J.
Published: May 2003

Background:  Scleroderma renal crisis (SRC) is a rare but feared complication of scleroderma. Angiotensin‐­converting enzyme (ACE) inhibition has significantly improved survival, but it is unknown whether prophy­lactic ACE inhibitors will prevent this complication.

Aims:  To determine: (i) the frequency of SRC in our cohort of well‐characterized scleroderma patients resident in South Australia, (ii) any predisposing clinical and serological features, (iii) median disease duration at which SRC occurs, (iv) possible precipitants, (v) disease outcome, and (vi) whether patients were taking ACE inhibitors prior to onset of SRC.

Methods
:  Systematic review of the clinical course of all patients registered on the South Australian Scleroderma Register.

Results:  SRC occurred in 16 patients. This constituted 2.8% of a total scleroderma cohort and 15% of the diffuse scleroderma cohort identified in South Australia. All 16 patients had diffuse cutaneous scleroderma. SRC occurred at a median disease duration of 15 months (range 1 week− 11 years). Disease outcome was poor (five deaths, three requiring long‐term dialysis and only two patients regaining a normal creatinine) despite aggressive antihypertensive treatment (including ACE inhibitors) in an intensive care or specialized renal unit. Two patients were later able to discontinue dialysis. Only two patients were taking small doses of ACE inhibitors prior to the onset of their SRC. The frequency of Scl‐70 was decreased in the SRC group (P = 0.003).

Conclusion
:  SRC is a rare event occurring in a small proportion of patients with diffuse scleroderma. The outcome of SRC was poor despite aggressive antihypertensive treatment. It is hypothesized that prophylactic ACE inhibition in susceptible patients might prevent or ameliorate this complication. (Intern Med J 2003; 33: 216−220)
Questioning the decision‐making capacity of surrogates
Authors: Bramstedt K. A.
Published: May 2003

When patients are unable to make medical decisions for themselves due to cognitive impairment, surrogate decision makers are often called on to guide the medical team. Important to any decision made on behalf of the patient is that the decision reflects the values and preferences of the patient in light of the patient's clinical status and prognosis. Challenges arise for the medical team when surrogates themselves have questionable decision‐making capacity due to psychosocial issues, conflict of interest, or the obvious projection of their own personal values and treatment preferences instead of the patient’s. Even if an alternative surrogate is available, there is no consensus on when and how to switch from the primary surrogate to the alternative surrogate. This paper uses a clinical case to explore the notion of surrogate decision‐making capacity, offering guidance for determining when it is appropriate to defer to an altern­ative surrogate, as well as guidance for managing the process of appointing the alternative as the new primary decision maker. (Intern Med J 2003; 33: 257−259)
Managing antituberculosis drug therapy by therapeutic drug monitoring of rifampicin and isoniazid
Authors: Ray J. , Gardiner I. , Marriott D.
Published: May 2003

Background:  Current therapeutic regimens with rifampicin and isoniazid have proven successful in treating tuberculosis, however, toxicity, therapeutic failure, relapse and multiple drug resistance are serious ­concerns. Optimizing drug dose using therapeutic drug monitoring (TDM) may be a better approach than administering therapy as a standard dose.

Aims:  To establish and evaluate a TDM service to ­optimize rifampicin and isoniazid therapy.

Methods:  A TDM service for rifampicin and isoniazid was established in November 1998. Drug concentration data were collected, with relevant information to interpret the results. The reason for the request, information on concomitant drug administration and a questionnaire to assess clinical response to the drug results were also obtained.

Results:  Ninety patient episodes were accepted for study. The rifampicin plasma concentrations showed significant scatter, with 46% of the rifampicin concentrations below the normal range and 2% above the normal range. Similarly, 48% of isoniazid concen­trations were below the lower target of the normal range and 29% were above the upper normal limit. There was a greater proportion of isoniazid concentrations above the normal range in female patients.

Conclusion:  Significant pharmacokinetic variability was observed for rifampicin and isoniazid in the patient population studied. Further, a substantial number of plasma concentrations fell outside the suggested normal range for both drugs. Isoniazid plasma concentrations were significantly higher in female patients compared with male patients. Despite these abnormal results, the dose of rifampicin and isoniazid was altered in only 17% of patients, however, many patients received follow‐up education because of the drug result. The service was considered valuable by 83% of respondents to the questionnaire. While TDM of rifampicin and isoniazid is a valuable tool to optimize the dose of these drugs in some patients, there is an urgent need for concentration−effect studies and possibly education on the principles and practice of TDM for these drugs. (Intern Med J 2003; 33: 229−234)
Extracellular phosphatase activity of natural plankton studied with ELF97 phosphate: fluorescence quantification and labelling kinetics
Authors: Nedoma Jiří , Štrojsová Alena , Vrba Jaroslav , Komárková Jaroslava , Šimek Karel
Published: May 2003

ELF®97 phosphate (ELFP) is a phosphatase substrate which produces ELF®97 alcohol (ELFA), a fluorescent water‐insoluble product, upon hydrolysis. We studied the kinetics of ELFA precipitation in freshwater samples at levels of total plankton and single phytoplankton cells, and tested the suitability of ELFP for measurement of surface‐bound algal extracellular phosphatases. Samples from acidic Plešné Lake (pH ∼ 5; high phosphatase activity) and eutrophic Římov reservoir (pH ∼7–10; moderate phosphatase activity) were incubated with ELFP for 5–300 min, fixed with HgCl2 and filtered through polycarbonate filters. Relative fluorescence of filter‐retained ELFA precipitates was quantified with image analysis. Time‐courses of ELFA formation exhibited lag periods followed by finite periods of linear increase. In Plešné Lake, lag‐times were shorter (1–18 min) and rates of increase in ELFA fluorescence higher (by ∼2 orders of magnitude) than in Římov reservoir (lag‐times 30–200 min). Similar patterns of ELFA formation kinetics were also observed in Plešné Lake samples in cuvette spectrofluorometer measurements (which failed in Římov reservoir). Linear regression of seasonal data on rates of increase in ELFA fluorescence from image cytometry and spectrofluorometry (r2 = 0.65, n = 10) allowed for calibration of image cytometry in terms of amount of cell‐associated ELFA. Preliminary measurements of extracellular phosphatase activities of several algae resulted in rates (10–2260 fmol cell−1 h−1) which are comparable to data reported in the literature for algal cultures.
Extraradical mycelium of the arbuscular mycorrhizal fungus Glomus lamellosum can take up, accumulate and translocate radiocaesium under root‐organ culture conditions
Authors: Declerck Stéphane , Dupré de Boulois Hervé , Bivort Céline , Delvaux Bruno
Published: May 2003

Radiocaesium enters the food chain when plants absorb it from soil, in a process that is strongly dependent on soil properties and plant and microbial species. Among the microbial species, arbuscular mycorrhizal (AM) fungi are obligate symbionts that colonize the root cortex of many plants and develop an extraradical mycelial (ERM) network that ramifies in the soil. Despite the well‐known involvement of this ERM network in mineral nutrition and uptake of some heavy metals, only limited data are available on its role in radiocaesium transport in plants. We used root‐organ culture to demonstrate that the ERM of the AM fungus Glomus lamellosum can take up, possibly accumulate and unambiguously translocate radiocaesium from a 137Cs‐labelled synthetic root‐free compartment to a root compartment and within the roots. The accumulation of 137Cs by hyphae in the root‐free compartment may be explained by sequestration in the hyphae or by a bottleneck effect resulting from a limited number of hyphae crossing the partition between the two compartments. Uptake and translocation resulted from the incorporation of 137Cs into the fungal hyphae, as no 137Cs was detected in mycorrhizal roots treated with formaldehyde. The importance of the translocation process was indicated by the correlation between 137Cs measured in the roots and the total hyphal length connecting the roots with the labelled compartment. 137Cs may be translocated via a tubular vacuolar system or by cytoplasmic streaming per se.
Monitoring of alkane‐degrading bacteria in a sea‐water microcosm during crude oil degradation by polymerase chain reaction based on alkane‐catabolic genes
Authors: Sei Kazunari , Sugimoto Yoshiro , Mori Kazuhiro , Maki Hideaki , Kohno Tetsuro
Published: May 2003

Behaviour of microbial populations responsible for degrading n‐alkanes, a major component of crude oil, was monitored during crude oil degradation in a sea‐water microcosm by both traditional colony culturing and molecular techniques. A DNA extraction method applicable to crude oil‐amended sea‐water samples was developed to obtain DNA applicable to most probable number (MPN) polymerase chain reaction (PCR). The population of alkane‐degrading bacteria responsible for degradation of n‐alkanes in a crude oil‐amended microcosm altered, so that shorter alkanes were degraded first by alkane‐degrading bacteria possessing alkane hydroxylase genes from group I (Kohno et al., 2002, Microb Environ 17: 114–121) and longer ones afterwards by those possessing alkane hydroxylase genes from group II. Thus, the degradation mechanism of the n‐alkanes can be clarified during crude oil degradation. Application of the method of detecting different types of alkane‐catabolic genes, as shown in the present study, enabled bacterial groups preferring alkanes of either shorter or longer chain lengths to be enumerated selectively.
Lymphocyte Homing to Bronchus-associated Lymphoid Tissue (BALT) Is Mediated by L-selectin/PNAd, α4β1 Integrin/VCAM-1, and LFA-1 Adhesion Pathways
Authors: Xu Baohui , Wagner Norbert , Pham Linh Nguyen , Magno Vincent , Shan Zhongyan , Butcher Eugene C. , Michie Sara A.
Published: May 2003

Bronchus-associated lymphoid tissue (BALT) participates in airway immune responses. However, little is known about the lymphocyte–endothelial adhesion cascades that recruit lymphocytes from blood into BALT. We show that high endothelial venules (HEVs) in BALT express substantial levels of VCAM-1, in marked contrast to HEVs in other secondary lymphoid tissues. BALT HEVs also express the L-selectin ligand PNAd. Anti–L-selectin, anti-PNAd, and anti–LFA-1 mAbs almost completely block the homing of B and T lymphocytes into BALT, whereas anti–α4 integrin and anti–VCAM-1 mAbs inhibit homing by nearly 40%. α4β7 integrin and MAdCAM-1 are not involved. Importantly, we found that mAbs against α4 integrin and VCAM-1 significantly block the migration of total T cells (80% memory phenotype) but not naive T and B cells to BALT. These results suggest that an adhesion cascade, which includes L-selectin/PNAd, α4β1 integrin/VCAM-1, and LFA-1, targets specific lymphocyte subsets to BALT. This high level of involvement of α4β1 integrin/VCAM-1 is unique among secondary lymphoid tissues, and may help unify lymphocyte migration pathways and immune responses in BALT and other bronchopulmonary tissues.
Antigen-capturing Cells Can Masquerade as Memory B Cells
Authors: Bell Jennifer , Gray David
Published: May 2003

As well as classically defined switched immunoglobulin isotype-expressing B cells, memory B cells are now thought to include IgM-expressing cells and memory cells that lack B cell lineage markers, such as B220 or CD19. We set out to compare the relative importance of memory B cell subsets with an established flow cytometry method to identify antigen-specific cells. After immunization with PE, we could detect B220+ and, as reported previously, B220− antigen-binding cells (McHeyzer-Williams, L.J., M. Cool, and M.G. McHeyzer-Williams. 2001. J. Immunol. 167:1393–1405). The B220−PE+ cells bore few markers typical of B cells, but resembled myeloid cells. Further analysis of the antigen-binding characteristics of these cells showed that, upon immunization with two fluorescent proteins, the B220− cells could bind both. Furthermore, this subpopulation was detected in RAG1−/− mice after transfer of anti-PE mouse serum. These data strongly suggest that these cells capture serum Ig, via Fc receptors, and thus appear antigen-specific. Investigation of these antigen-capturing cells in a variety of knockout mice indicates that they bind monomeric IgG in an FcγR1 (CD64)–dependent manner. We find no evidence of a B220− memory B cell population that is not explicable by antigen-capturing cells, and warn that care must be taken when using antigen-specificity or surface IgG as an indicator of B cell memory.
Mlh1 Can Function in Antibody Class Switch Recombination Independently of Msh2
Authors: Schrader Carol E. , Vardo Joycelyn , Stavnezer Janet
Published: May 2003

Mismatch repair proteins participate in antibody class switch recombination, although their roles are unknown. Previous nucleotide sequence analyses of switch recombination junctions indicated that the roles of Msh2 and the MutL homologues, Mlh1 and Pms2, differ. We now asked if Msh2 and Mlh1 function in the same pathway during switch recombination. Splenic B cells from mice deficient in both these proteins were induced to undergo switching in culture. The frequency of switching is reduced, similarly to that of B cells singly deficient in Msh2 or Mlh1. However, the nucleotide sequences of the Sμ-Sγ3 junctions resemble junctions from Mlh1- but not from Msh2-deficient cells, suggesting Mlh1 functions either independently of or before Msh2. The substitution mutations within S regions that are known to accompany switch recombination are increased in Msh2- and Mlh1 single-deficient cells and further increased in the double-deficient cells, again suggesting these proteins function independently in class switch recombination. The finding that MMR functions to reduce mutations in switch regions is unexpected since MMR proteins have been shown to contribute to somatic hypermutation of antibody variable region genes.
Ludwig von Mises: The Man and His Economics
Authors: Gonce R. A.
Published: May 2003

Kirzner, Israel M. (2001). Ludwig von Mises: The Man and His Economics. Wilmington, DE: ISI Books. ISBN 1‐882926‐61‐7. xv, 226 pp.
Reconsidering the Marielito Legacy: Race/Ethnicity, Nativity, and Homicide Motives*
Authors: Martinez Ramiro , Nielsen Amie L. , Lee Matthew T.
Published: May 2003

Objective.This article investigates how race/ethnicity is associated with specific types of violent crime such as killings between intimates, robbery homicide, or drug‐related killings. We extend the study of the role of race and ethnicity for violence by examining five ethnic/immigrant groups, including the Mariel Cubans—a group singled out by many as particularly drug‐crime‐prone.

Methods.Using 1980 through 1990 homicide data for the City of Miami, we use multinomial logistic regression to examine the association between race/ethnicity, nativity, and several types of homicide motives.

Results.Contrary to popular expectations, ethnicity and immigration status rarely play a role in the types of homicide involvement of victims or violators. Incident characteristics, such as multiple offenders, or gender and age, were consistently more important influences in shaping homicide circumstances.

Conclusions.The analyses revealed few significant relationships between immigration status and homicide motives, suggesting that immigrant groups like the Marielitos have more in common with native groups' experiences of criminal violence than is commonly assumed.
HETEROGENEOUS DISTRIBUTION OF THE MASSES AS THE SOURCE OF THERMODYNAMIC OSCILLATIONS IN POLYMERS
Authors: MAŠKOVIĆ Lj. , TOŠIĆ B. S.
Published: May 2003

The subject of the study are the thermodynamic characteristics of the phonon gas in the chains with heterogeneous mass distribution. The expressions for the internal energy, entropy and free energy of the system are evaluated both in the region of high and low temperature. It is shown that the mass heterogeneity is the source of the strong dissipation of the vibrational energy, which causes all thermodynamic functions of the chains to be quasi-periodic functions of the temperature.
STUDY OF SMALL METALLIC NANOPARTICLES: AN AB-INITIO FULL-POTENTIAL MUFFIN-TIN ORBITALS BASED MOLECULAR DYNAMICS STUDY OF SMALL Cu CLUSTERS
Authors: KABIR MUKUL , MOOKERJEE ABHIJIT , DATTA RADHIKA PROSAD , BANERJEA AMITAVA , BHATTACHARYA A. K.
Published: May 2003

The equilibrium structures and cohesive energies of small Cun clusters using the full-potential muffin-tin orbitals (FP-LMTO) based molecular dynamics (MD) have been studied for n ≤ 9. The results obtained have been compared with other chemical methods. We propose the FP-LMTO-MD technique to be a useful starting point of more empirical methods which can efficiently deals with larger cluster sizes relevant for nanoparticles.
VALUATION AND OPTIMAL EXERCISE TIME FOR THE BANXICO PUT OPTION
Authors: FERNÁNDEZ BEGOÑNA FERNÁNDEZ , BARRERA PATRICIA SAAVEDRA
Published: May 2003

Since 1996, the Central Bank of México issues a put option in order to buy American Dollars as a way of increasing its international reserves. This is an exotic option that gives the right to the Mexican banks to sell this currency to the Central Bank at the price of the day before the date of exercise. The option has a maturity of one month and can be exercised on any day during this period, subject to an additional condition that depends on the average price of the Dollar during the previous 20 days. In this work we study the valuation and the optimal time of exercise of this option under the Binomial and the Black–Scholes Models. The optimal time of exercise is found for the Binomial model and a rule of exercise is proposed for the Black–Scholes Model. Numerical results are included to illustrate the performance of this rule of exercise.