bluuebunny/crossref_metadata_2025 huggingface dataset:
Phylogenetic relationships of the Culicomorpha inferred from 18S and 5.8S ribosomal DNA sequences (Diptera: Nematocera)
Authors: Miller B. R. , Crabtree M. B. , Savage H. M.
Published: July 2007

We investigated the evolutionary origins of the mosquito family Culicidae by examination of 18S and 5.8S ribosomal gene sequence divergence. Phylogenetic analyses demonstrated that within the infraorder Culicomorpha, taxa in the families Corethrellidae, Chaoboridae and Culicidae formed a monophyletic group; there was support for a sister relationship between this lineage and a representative of the Chironomldae. A chaoborid midge was the closest relative of the mosquitoes. Taxa from four genera of mosquitoes formed a monophyletic group; lack of a spacer in the 5.8S gene was unique to members of the Culicidae. A member of the genus Anopheles formed the most basal lineage among the mosquitoes analysed. Phylogenetic relationships were unresolved for representatives in the families Dixidae, Simuliidae and Ceratopogonidae.
Heterogeneity of the internal transcribed spacer (ITS‐2) region within individual deer ticks
Authors: Rich S. M. , Rosenthal B. M. , Telford S. R. , Spielman A. , Harti D. L. , Ayala F. J.
Published: July 2007

To determine whether nuclear rDNA sequences provide a useful means for assessing the structure of populations of Ixodes ticks, we compared variability among copies of an internal transcribed spacer (ITS‐2) sequence within individual ticks to the variability between ticks. At least 4% of the nucleotides comprising this sequence vary among the copies present within individual ticks. ITS‐2 diversity in each of two ticks is nearly half as great as that reported between ticks from geographically disparate populations. Because individual ticks retain ancestral polymorphism, ITS‐2 variation does not accurately reflect descent relationships among these ticks. Sequencing single copies of PCR‐amplified ITS‐2 therefore does not permit assessment of the phylogenetic relationships among the I. ricinus‐like ticks in eastern North America. We recommend caution in future analyses, and emphasize the importance of procedures designed to ensure that the many paralogous coples of the rDNA cistron have been sufficiently homogenized by concerted evolutionary processes. Such precautionary measures will make certain that phylogenetic trees based on these gene sequences reflect the phyletic relatedness of the biological species.
Cloning of cDNAs encoding Bombyx homologues of Cdc2 and Cdc2‐related kinase from eggs
Authors: Iwasaki H. , Takahash M. , Nilmi T. , Yamashita O. , Yaginuma T.
Published: July 2007

In diapausing eggs of the silkworm, Bombyx mori, embryonic cells are arrested at G2 phase. The ability to undertake cell division is resumed in the course of diapause termination caused by such a treatment as acclimation to 5°C. As an initial trial to investigate the relationship between diapause and embryonic cell cycling, we have cloned and sequenced two Bombyx cDNAs encoding two distinct cdc2‐related Ser/Thr protein kinases. One (Bm cdc2) encoded a 37.0 kDa protein which had all of the domains characteristic of other Cdc2 kinases. The other (Bcdrk) encoded a 45.1 kDa protein that was most similar to Drosophila and human cdc2‐related protein kinases (Dcdrk protein and PISSRLE kinase). Northern blot analysis was carried out to examine levels of Bm cdc2 and Bcdrk mRNA during embryogenesis of non‐diapause eggs. The result demonstrated that the mRNA level of Bm cdc2 appeared to correspond to the activity of nuclear/cellular division in non‐diapause eggs, and that the developmental profile in the level of Bcdrk mRNA was somewhat different from that of Bm cdc2 mRNA.
Quality of life: verification and use of a self‐ assessment scale in two patient populations
Authors: Sutcliffe Jayne , Holmes Susan
Published: July 2007

The study described further evaluates the use of the Holmes & Dickerson linear analougue self‐ assessment scale in asessing the quality of both in ‐patients and out‐patients undergoing radiotherapy for the treatment of malignant disease. The scale is shown to be feasible for use in both clinical settings and to be noth reliable and valid. It is quick to use, easy to score and demonstrates marked differences between the patient populations, These differences are discussed and supported on clinical grounds. The results emphasize the fact that cancer patients cannot be regarded as a homogeneous group and highlight the need for care to cannot be planned on an indicidual basis. Similarly, the need for a means by which individual response can be assessed is demonstrated. It is suggested that this self‐ assessment technique may be of considerable value in such assessment
The relative effects of raptor predation and shooting on overwinter mortality of grey partridges in the United Kingdom
Authors: WATSON M , AEBISCHER N. J , POTTS G. R , EWALD J. A
Published: July 2007

Factual information is key to resolving conflicts between raptor conservation and gamebird management, especially when the conservation status of one of the species involved is threatened. The grey partridge Perdix perdix is a UK Biodiversity Action Plan species because of a marked decline in abundance caused by agricultural intensification. Recently, the number of raptors present on farmland and the commercial shooting of red‐legged partridges Alectoris rufa have both increased. To inform conservation action, the relative impacts of these two factors on grey partridge populations urgently require quantification.

On our study site areas of low density of grey partridges coincided with areas of high raptor density. However, these areas were managed intensively for shooting and for two areas that suffered local partridge extinction, the 3‐year average percentage of partridges shot exceeded 50%.

Grey partridge mortality to raptors between autumn and spring lay between 9·5% of autumn density (assumes losses to raptors occurred before shooting) and 15% of post‐shooting density (if all losses to raptors were post‐shooting). A deterministic model suggested that this rate of loss would reduce the equilibrium density of spring pairs by 11–26% relative to a situation without raptors. In comparison, shooting losses across the study area amounted to 35–39% of autumn density, more than double the losses to raptor predation, with a predicted reduction of 68–85% in equilibrium density of spring pairs.

Synthesis and applications. Shooting based on large‐scale releases of red‐legged partridges acts in a density‐independent manner and can lead to local grey partridge extinction. Removing the grey partridge from the UK quarry list would be counterproductive, as most action to boost wild grey partridge densities is carried out by enthusiasts with shooting as the incentive. However, it is imperative that managers of intensive shoots based on gamebird release adopt measures to reduce shooting pressure on wild grey partridges at low density. These include training shooters to distinguish between grey and red‐legged partridges and implementing a warning system (whistle) to alert the gun line when birds of the non‐target species are approaching. Such voluntary measures are effective in addressing overshooting, which has greater implications for grey partridge conservation than raptor predation.
Top predators: hot or not? A call for systematic assessment of biodiversity surrogates
Authors: Cabeza Mar , Arponen Anni , Van Teeffelen Astrid
Published: July 2007

Sergio et al. (2006) argue that top predators are justified conservation surrogates based on a case study where raptor presence is associated with high species richness of birds, butterflies and trees.

We question the methodology as well as the applicability of their results, and clarify differences between surrogates for biodiversity hotspots and surrogates for complementarity. We show that the results from Sergio et al. related to richness hotspots are not fully reliable and that the ability of top predators to identify complementary areas is not demonstrated. Given that complementarity‐based surrogate studies have produced mixed results for a variety of reasons, we clarify some methodological misunderstandings while encouraging further testing of functional groups as biodiversity surrogates.

Synthesis and applications. We call for caution in making generalizations, and emphasize that case studies on the use of surrogates should be conducted in a systematic manner. This will facilitate robust assessment across studies regarding the usefulness of particular species groups as biodiversity surrogates.
Molecular dating of the ‘Gondwanan’ plant family Proteaceae is only partially congruent with the timing of the break‐up of Gondwana
Authors: Barker Nigel P. , Weston Peter H. , Rutschmann Frank , Sauquet Hervé
Published: July 2007

Aim The flowering plant family Proteaceae is putatively of Gondwanan age, with modern and fossil lineages found on all southern continents. Here we test whether the present distribution of Proteaceae can be explained by vicariance caused by the break‐up of Gondwana.

Location Africa, especially southern Africa, Australia, New Zealand, South America, New Caledonia, New Guinea, Southeast Asia, Sulawesi, Tasmania.

Methods We obtained chloroplast DNA sequence data from therbcL gene, therbcL‐atpB spacer, and theatpB gene from leaf samples of forty‐five genera collected from the field and from living collections. We analysed these data using Bayesian phylogenetic and molecular dating methods, with five carefully selected fossil calibration points to obtain age estimates for the nodes within the family.

Results Four of eight trans‐continental disjunctions of sister groups within our sample of the Proteaceae post‐date the break‐up of Gondwana. These involve independent lineages, two with an Africa‐Australia disjunction, one with an Africa–South America disjunction, and one with a New Zealand–Australasia disjunction. The date of the radiation of the bird‐pollinated Embothriinae corresponds approximately to the hypothesized date of origin of nectar‐feeding birds in Australia.

Main conclusions The findings suggest that disjunct distributions in Proteaceae result from both Gondwanan vicariance and transoceanic dispersal. Our results imply that ancestors of some taxa dispersed across oceans rather than rafting with Gondwanan fragments as previously thought. This finding agrees with other studies of Gondwanan plants in dating the divergence of Australian, New Zealand and New Caledonian taxa in the Eocene, consistent with the existence of a shared, ancestral Eocene flora but contrary to a vicariance scenario based on accepted geological knowledge.
Co‐morbid medical and psychiatric illness and substance abuse in HCV‐infected and uninfected veterans
Authors: Butt A. A. , Khan U. A. , McGinnis K. A. , Skanderson M. , Kent Kwoh C.
Published: July 2007

Summary.  Comorbidities may affect the decision to treat chronic hepatitis C virus (HCV) infection. We undertook this study to determine the prevalence of these conditions in the HCV‐infected persons compared with HCV‐uninfected controls. Demographic and comorbidity data were retrieved for HCV‐infected and ‐uninfected subjects from the VA National Patient Care Database using ICD‐9 codes. Logistic regression was used to determine the odds of comorbid conditions in the HCV‐infected subjects. HCV‐uninfected controls were identified matched on age, race/ethnicity and sex. We identified 126 926 HCV‐infected subjects and 126 926 controls. The HCV‐infected subjects had a higher prevalence of diabetes, anaemia, hypertension, chronic obstructive pulmonary disease (COPD)/asthma, cirrhosis, hepatitis B and cancer, but had a lower prevalence of coronary artery disease and stroke. The prevalence of all psychiatric comorbidities and substance abuse was higher in the HCV‐infected subjects. In the HCV‐infected persons, the odds of being diagnosed with congestive heart failure, diabetes, anaemia, hypertension, COPD/asthma, cirrhosis, hepatitis B and cancer were higher, but lower for coronary artery disease and stroke. After adjusting for alcohol and drug abuse and dependence, the odds of psychiatric illness were not higher in the HCV‐infected persons. The prevalence and patterns of comorbidities in HCV‐infected veterans are different from those in HCV‐uninfected controls. The association between HCV and psychiatric diagnoses is at least partly attributable to alcohol and drug abuse and dependence. These factors should be taken into account when evaluating patients for treatment and designing new intervention strategies.
Hepatitis A seroprevalence and its relationship with environmental factors in children of different age groups in Kahramanmaras, Eastern Mediterranean region of Turkey
Authors: Kaya D. , Guler E. , Ekerbicer H. C. , Dilber C. , Karabiber H. , Guler S. , Davutoglu M. , Ciragil P.
Published: July 2007

Summary.  Hepatitis A infections are influenced by environmental and socioeconomic factors. Epidemiologic studies regarding hepatitis A virus (HAV) infection in Turkey have not previously examined these factors. We investigated HAV seroprevalence and its association with sociodemographic factors among children of various ages in the Eastern Mediterranean region of Turkey. The study included 1142 children (603 male and 539 female) between ages of 6 months and 18 years. Seropositivity in the whole group was 57.2%. HAV prevalence rates according to age groups were as follows: 35.5% in 6–23 months group, 19.2% in 2–5 years group, 74.3% in 6–10 years group, 83.0% in 11–14 years group, 92.8% in 15–18 years group. Risk factors that influenced seropositivity were; dense population, over‐crowded families, excessive number of siblings, low socioeconomic status and low education of the mother. As HAV seroprevalence in children older than 6 years of age is high, we recommend hepatitis A vaccination in this region after the first year of life.
High frequency of multiple paternity in the largest rookery of Mediterranean loggerhead sea turtles
Authors: ZBINDEN JUDITH A. , LARGIADÈR CARLO R. , LEIPPERT FABIO , MARGARITOULIS DIMITRIS , ARLETTAZ RAPHAËL
Published: July 2007

Mating systems are a central component in the evolution of animal life histories and in conservation genetics. The patterns of male reproductive skew and of paternal shares in batches of offspring, for example, affect genetic effective population size. A prominent characteristic of mating systems of sea turtles seem to be a considerable intra‐ and interspecific variability in the degree of polyandry. Because of the difficulty of observing the mating behaviour of sea turtles directly in the open sea, genetic paternity analysis is particularly useful for gaining insights into this aspect of their reproductive behaviour. We investigated patterns of multiple paternity in clutches of loggerhead sea turtles in the largest Mediterranean rookery using four highly variable microsatellite loci. Furthermore, we tested for a relationship between the number of fathers detected in clutches and body size of females. More than one father was detected in the clutches of 14 out of 15 females, with two clutches revealing the contribution of at least five males. In more than half the cases, the contributions of different fathers to a clutch did not depart from equality. The number of detected fathers significantly increased with increasing female body size. This relationship indicates that males may prefer to mate with large, and therefore productive, females. Our results suggest that polyandry is likely to increase effective population size compared to a population in which females would mate with only one male; male reproductive contributions being equal.
Rudbeck’s Complaint – A 17th‐Century Latin Letter Relating to Basic Immunology
Authors: Ambrose C. T.
Published: July 2007

Basic immunology can be said to have its origin in the mid‐17th‐century with the discovery of the peripheral lymphatics. They completed the gross anatomical picture of the lymphatic system, which is the basis for much of the immune response. Their recognition almost simultaneously by two Scandinavian anatomists led to a protracted war of words over priority of discovery, pitting a young Swedish medical student (Olof Rudbeck) against an honored Danish anatomy professor (Thomas Bartholin). In a 752‐word letter in Latin, Rudbeck charged Bartholin with pre‐dating a key observation, thereby giving priority of discovery to the latter. The purpose of this paper is to provide an English translation of this accusatory letter. It is a notable document in basic immunology, for it cites much of the knowledge then current in the field. And by raising the issue of priority, the letter indirectly piqued the interest of the scientific community in the lymphatic system and hastened its study. Examining the system's various functions in health and disease led to this new discipline.
Rice ABERRANT PANICLE ORGANIZATION 1, encoding an F‐box protein, regulates meristem fate
Authors: Ikeda Kyoko , Ito Momoyo , Nagasawa Nobuhiro , Kyozuka Junko , Nagato Yasuo
Published: July 2007

Inflorescence architecture is one of the most important agronomical traits. Characterization of rice aberrant panicle organization 1 (apo1) mutants revealed that APO1 positively controls spikelet number by suppressing the precocious conversion of inflorescence meristems to spikelet meristems. In addition, APO1 is associated with the regulation of the plastchron, floral organ identity, and floral determinacy. Phenotypic analyses of apo1 and floral homeotic double mutants demonstrate that APO1 positively regulates class‐C floral homeotic genes, but not class‐B genes. Molecular studies revealed that APO1 encodes an F‐box protein, an ortholog of Arabidopsis UNUSUAL FLORAL ORGAN (UFO), which is a positive regulator of class‐B genes. Overexpression of APO1 caused an increase in inflorescence branches and spikelets. As the mutant inflorescences and flowers differed considerably between apo1 and ufo, the functions of APO1 and UFO appear to have diverged during evolution.
Conservation and divergence of APETALA1/FRUITFULL‐like gene function in grasses: evidence from gene expression analyses
Authors: Preston Jill C. , Kellogg Elizabeth A.
Published: July 2007

Duplicated APETALA1/FRUITFULL (AP1/FUL) genes show distinct but overlapping patterns of expression within rice (Oryza sativa) and within ryegrass (Lolium temulentum), suggesting discrete functional roles in the transition to flowering, specification of spikelet meristem identity, and specification of floral organ identity. In this study, we analyzed the expression of the AP1/FUL paralogues FUL1 and FUL2 across phylogenetically disparate grasses to test hypotheses of gene function. In combination with other studies, our data support similar roles for both genes in spikelet meristem identity, a general role for FUL1 in floral organ identity, and a more specific role for FUL2 in outer floral whorl identity. In contrast to Arabidopsis AP1/FUL genes, expression of FUL1 and FUL2 is consistent with an early role in the transition to flowering. In general, FUL1 has a wider expression pattern in all spikelet organs than FUL2, but both genes are expressed in all spikelet organs in some cereals. FUL1 and FUL2 appear to have multiple redundant functions in early inflorescence development. We hypothesize that sub‐functionalization of FUL2 and interaction of FUL2 with LHS1 could specify lemma and palea identity in the grass floret.
A multicolored set of in vivo organelle markers for co‐localization studies in Arabidopsis and other plants
Authors: Nelson Brook K. , Cai Xue , Nebenführ Andreas
Published: July 2007

Genome sequencing has resulted in the identification of a large number of uncharacterized genes with unknown functions. It is widely recognized that determination of the intracellular localization of the encoded proteins may aid in identifying their functions. To facilitate these localization experiments, we have generated a series of fluorescent organelle markers based on well‐established targeting sequences that can be used for co‐localization studies. In particular, this organelle marker set contains indicators for the endoplasmic reticulum, the Golgi apparatus, the tonoplast, peroxisomes, mitochondria, plastids and the plasma membrane. All markers were generated with four different fluorescent proteins (FP) (green, cyan, yellow or red FPs) in two different binary plasmids for kanamycin or glufosinate selection, respectively, to allow for flexible combinations. The labeled organelles displayed characteristic morphologies consistent with previous descriptions that could be used for their positive identification. Determination of the intracellular distribution of three previously uncharacterized proteins demonstrated the usefulness of the markers in testing predicted subcellular localizations. This organelle marker set should be a valuable resource for the plant community for such co‐localization studies. In addition, the Arabidopsis organelle marker lines can also be employed in plant cell biology teaching labs to demonstrate the distribution and dynamics of these organelles.
TECHNICAL ADVANCE: Split luciferase complementation assay to study protein–protein interactions in Arabidopsis protoplasts
Authors: Fujikawa Yukichi , Kato Naohiro
Published: July 2007

We developed a split luciferase complementation assay to study protein–protein interactions in Arabidopsis protoplasts. In this assay, the N‐ and C‐terminal fragments of Renilla reniforms luciferase are translationally fused to bait and prey proteins, respectively. When the proteins interact, split luciferase becomes activated and emits luminescence that can be measured by a microplate luminometer. Split luciferase activity was measured by first transforming protoplasts with a DNA vector in a 96‐well plate. DNA vector expressing both bait and prey genes was constructed through two independent in vitro DNA recombinant reactions, Gateway and Cre‐loxP. As proof of concept, we detected the protein–protein interactions between the nuclear histones 2A and 2B, as well as between membrane proteins SYP (syntaxin of plant) 51 and SYP61, in Arabidopsis protoplasts.
Differential gene expression in Arabidopsis wild‐type and mutant anthers: insights into anther cell differentiation and regulatory networks
Authors: Wijeratne Asela J. , Zhang Wei , Sun Yujin , Liu Wenlei , Albert Reka , Zheng Zhengui , Oppenheimer David G. , Zhao Dazhong , Ma Hong
Published: July 2007

In flowering plants, the anther contains highly specialized reproductive and somatic cells that are required for male fertility. Genetic studies have uncovered several genes that are important for anther development. However, little information is available regarding most genes active during anther development, including possible relationships between these genes and genetically defined regulators. In Arabidopsis, two previously isolated male‐sterile mutants display dramatically altered anther cell differentiation patterns. The sporocyteless (spl)/nozzle (nzz) mutant is defective in the differentiation of primary sporogenous cells into microsporocytes, and does not properly form the anther wall. The excess microsporocytes1 (ems1)/extrasporogenous cells (exs) mutants produce excess microsporocytes at the expense of the tapetum. To gain additional insights into microsporocyte and tapetum differentiation and to uncover potential genetic interactions, expression profiles were compared between wild‐type anthers (stage 4–6) and those of the spl or ems1 mutants. A total of 1954 genes were found to be differentially expressed in the ems1 and/or spl anthers, and these were grouped into 14 co‐expression clusters. The presence of genes with known and predicted functions in specific clusters suggests potential functions for other genes in the same cluster. To obtain clues about possible co‐regulation within co‐expression clusters, we searched for shared cis‐regulatory motifs in putative promoter regions. Our analyses were combined with data from previous studies to develop a model of the anther gene regulatory network. This model includes hypotheses that can be tested experimentally to gain further understanding of the mechanisms controlling anther development.
Proteomic and biochemical evidence links the callose synthase in Nicotiana alata pollen tubes to the product of the NaGSL1 gene
Authors: Brownfield Lynette , Ford Kris , Doblin Monika Susanne , Newbigin Ed , Read Steve , Bacic Antony
Published: July 2007

The NaGSL1 gene has been proposed to encode the callose synthase (CalS) enzyme from Nicotiana alata pollen tubes based on its similarity to fungal 1,3‐β‐glucan synthases and its high expression in pollen and pollen tubes. We have used a biochemical approach to link the NaGSL1 protein with CalS enzymic activity. The CalS enzyme from N. alata pollen tubes was enriched over 100‐fold using membrane fractionation and product entrapment. A 220 kDa polypeptide, the correct molecular weight to be NaGSL1, was specifically detected by anti‐GSL antibodies, was specifically enriched with CalS activity, and was the most abundant polypeptide in the CalS‐enriched fraction. This polypeptide was positively identified as NaGSL1 using both MALDI‐TOF MS and LC‐ESI‐MS/MS analysis of tryptic peptides. Other low‐abundance polypeptides in the CalS‐enriched fractions were identified by MALDI‐TOF MS as deriving from a 103 kDa plasma membrane H+‐ATPase and a 60 kDa β‐subunit of mitochondrial ATPase, both of which were deduced to be contaminants in the product‐entrapped material. These analyses thus suggest that NaGSL1 is required for CalS activity, although other smaller (<30 kDa) or low‐abundance proteins could also be involved.
REVIEW ON CPP: Measuring reward with the conditioned place preference (CPP) paradigm: update of the last decade
Authors: Tzschentke Thomas M.
Published: July 2007

Conditioned place preference (CPP) continues to be one of the most popular models to study the motivational effects of drugs and non‐drug treatments in experimental animals. This is obvious from a steady year‐to‐year increase in the number of publications reporting the use this model. Since the compilation of the preceding review in 1998, more than 1000 new studies using place conditioning have been published, and the aim of the present review is to provide an overview of these recent publications. There are a number of trends and developments that are obvious in the literature of the last decade. First, as more and more knockout and transgenic animals become available, place conditioning is increasingly used to assess the motivational effects of drugs or non‐drug rewards in genetically modified animals. Second, there is a still small but growing literature on the use of place conditioning to study the motivational aspects of pain, a field of pre‐clinical research that has so far received little attention, because of the lack of appropriate animal models. Third, place conditioning continues to be widely used to study tolerance and sensitization to the rewarding effects of drugs induced by pre‐treatment regimens. Fourth, extinction/reinstatement procedures in place conditioning are becoming increasingly popular. This interesting approach is thought to model certain aspects of relapse to addictive behavior and has previously almost exclusively been studied in drug self‐administration paradigms. It has now also become established in the place conditioning literature and provides an additional and technically easy approach to this important phenomenon. The enormous number of studies to be covered in this review prevented in‐depth discussion of many methodological, pharmacological or neurobiological aspects; to a large extent, the presentation of data had to be limited to a short and condensed summary of the most relevant findings.
Enhancing employee capacity to prioritize health insurance benefits
Authors: Danis Marion , Goold Susan Dorr , Parise Carol , Ginsburg Marjorie
Published: July 2007

Objective  To demonstrate that employees can gain understanding of the financial constraints involved in designing health insurance benefits.

Background  While employees who receive their health insurance through the workplace have much at stake as the cost of health insurance rises, they are not necessarily prepared to constructively participate in prioritizing their health insurance benefits in order to limit cost.

Design  Structured group exercises.

Setting and participants  Employees of 41 public and private organizations in Northern California.

Intervention  Administration of the CHAT (Choosing Healthplans All Together) exercise in which participants engage in deliberation to design health insurance benefits under financial constraints.

Main outcome measures  Change in priorities and attitudes about the need to exercise insurance cost constraints.

Results  Participants (N = 744) became significantly more cognizant of the need to limit insurance benefits for the sake of affordability and capable of prioritizing benefit options. Those agreeing that it is reasonable to limit health insurance coverage given the cost increased from 47% to 72%.

Conclusion  It is both possible and valuable to involve employees in priority setting regarding health insurance benefits through the use of structured decision tools.
Ferric and cupric reductase activities by iron‐limited cells of the green alga Chlorella kessleri: quantification via oxygen electrode
Authors: Weger Harold G. , Walker Crystal N. , Fink Michael B.
Published: July 2007

The colorimetric Fe2+ indicators bathophenanthroline disulfonic acid (BPDS) and 3‐(2‐pyridyl)‐5,6‐bis(4‐phenylsulfonic acid)‐1,2,4‐triazine (FZ) are routinely used to assay for plasma membrane ferric reductase activity in iron‐limited algal cells and also in roots from iron‐limited plants. Ferric reductase assays using these colorimetric indicators must take into account the fact that Fe3+ chelators (e.g. ethylenediaminetetraacetic acid) can also in general bind Fe2+ and may therefore compete with the colorimetric Fe2+ indicators, leading to the potential for underestimation of the ferric reduction rate. Conversely, the presence of BPDS or FZ may also facilitate the reduction of Fe3+ chelates, potentially leading to overestimation of ferric reduction rates. Last, both BPDS and FZ have non‐negligible affinities for Fe3+ in addition to their well‐known affinities for Fe2+; this leads to potential difficulties in ascertaining whether free and/or chelated Fe3+ are potential substrates for the ferric reductase. Similar issues arise when assaying for cupric reductase activity using the colorimetric Cu+ indicator bathocuproinedisulfonic acid (BCDS). In this paper, we describe an oxygen‐electrode‐based assay (conducted in darkness) for both ferric and cupric reductase activities that does not use colorimetric indicators. Using this assay system, we show that the plasma membrane metal reductase activity of iron‐limited cells of the green alga Chlorella kessleri reduced complexed Fe3+ (i.e. Fe3+ chelates) but did not reduce free (non‐chelated) Fe3+, and also reduced free Cu2+ to Cu+, but did not reduce Cu2+ that was part of Cu2+ chelates. We suggest that the potential for reduction of free Fe3+ cannot be adequately assayed using colorimetric assays. As well, the BPDS‐based assay system consistently yielded similar estimates of ferric reductase activity compared with the O2‐electrode‐based assays at relatively low Fe3+ concentration, but higher estimates at higher Fe3+ concentrations with chelators other than desferrioxamine mesylate. With respect to cupric reductase activity, the O2 electrode consistently provided much higher estimates; we suggest that this was as a result of Cu2+ chelation by BCDS leading to a large underestimation of the true cupric reduction rate. These results suggest that an O2‐electrode‐based metal reductase assay system has some specific advantages compared with the traditional colorimetric assay system, including especially the ability to discriminate between the reduction of free metal ions and chelated metal ions.
Response of Rice (Oryza sativa L.) Tillering to Sub‐ambient Levels of Ultraviolet‐B Radiation
Authors: Mohammed A. R. , Rounds E. W. , Tarpley L.
Published: July 2007

The negative impact of enhanced ultraviolet‐B (UV‐B) radiation has been demonstrated for rice, but few studies have examined the effects of low UV‐B radiation on rice growth and physiology. The objective of this study was to determine the effects of low UV‐B radiation on rice physiology with special emphasis on tiller initiation and development in two popular US rice cultivars, ‘Cocodrie’ and ‘Clearfield 161 (CL161)’. Plants received no natural UV‐B radiation because of the UV‐absorption characteristics of the greenhouse glass, hence UV‐B was artificially supplied by supplemental UV‐B lighting. Plants were grown in soil collected from research plots, and were exposed to UV‐B radiation of 0, 4 (sub‐ambient) or 8 kJ m−2 day−1 (ambient) for 29 days in one experiment and 87 days in a second experiment. ‘Cocodrie’ had no differential response among 0, 4 and 8 kJ m−2 day−1 UV‐B treatments for all the parameters measured except for plant height, which showed 5% decrease at ambient UV‐B conditions. For ‘CL161’ sub‐ambient UV‐B radiation exposure decreased vegetative tiller production (25%) and total panicle dry weight (15%). The decrease in tiller production was not due to a decrease in carbohydrate content or increase in auxin content under the low UV‐B radiation.
The Influence Of Salinity On Verticillium dahliae In Stem Cuttings Of Five Olive Cultivars
Authors: Levin A. G. , Lavee S. , Tsror (Lahkim) L.
Published: July 2007

Verticillium dahliae represents one of the main limiting factors in olive production in the Mediterranean countries. Increasing shortage of fresh water and land, increase the pressure on using alternative sources of marginal or saline water, and land previously cropped with V. dahliae host plants. The objective of the present study was to evaluate the influence of salinity on V. dahliae expression in olive stem cuttings. V. dahliae‐inoculated cuttings of cvs. Picual, Frantoio, Mansanillo and Barnea, showed higher senescence symptoms than their non‐inoculated controls. Colonization levels obtained in cv. Picual were significantly higher than in cv. Frantoio. Manzanillo was the most sensitive cultivar to salinity alone, with significant senescence symptoms in 4 and 6 dS/m NaCl treatments. When cv. Manzanillo was exposed to both salinity and V. dahliae, significantly higher senescence symptoms were obtained as compared with each of them separately. Senescence symptoms of cv. Picual exposed to V. dahliae, whether or not in combination with saline solutions, were significantly higher than those when cuttings were exposed to a saline solution alone. In cv. Frantoio, which is more resistant to salinity than the other cultivars, significantly high senescence symptoms were observed only in combination of V. dahliae and high saline concentration (8 dS/m). The fungal colonization index in cv. Manzanillo in high salinity (8 dS/m) was significantly higher than in the treatment without salt. In cv. Barnea, colonization index in 8 dS/m salinity was significantly higher than in the 4 dS/m concentration or control (fresh water). In conclusion, our findings demonstrate the interaction between V. dahliae and saline irrigation in various cultivars. Thus, stem cuttings could serve as an effective screening method in breeding olive clones for V. dahliae resistance, salt tolerance and their interaction.
Dermatophytoses in cats and humans in central Italy: epidemiological aspects
Authors: Iorio R. , Cafarchia C. , Capelli G. , Fasciocco D. , Otranto D. , Giangaspero A.
Published: July 2007

Two hundred hair/skin samples were collected from 2002 to 2004 from two groups of cats (privately owned and stray cats from a shelter) and 165 samples were obtained during the same period from persons in whom dermatophyte infection was highly suspected. The epidemiological data were statistically evaluated. Thirteen of the 100 privately owned cats (13%) and 100% of the stray cats were positive; of the 165 human samples examined 109 (66%) were positive for dermatophytes. Microsporum canis was the most common dermatophyte isolated in both cat groups while Trichophyton mentagrophytes was the most common in humans. Interestingly, a geophylic dermatophyte species (Microsporum gypseum) was found to be present and associated with clinical signs. Living in the countryside proved to be a risk factor for dermatophytoses in privately owned cats while in humans the main risk factor for M. canis was contact with animals followed by young age. None of the variables considered was associated with positivity for T. mentagrophytes while positivity for other fungi was correlated with life in the countryside.
Differential stripping: introduction of a method to show the penetration of topically applied antifungal substances into the hair follicles
Authors: Ossadnik M. , Czaika V. , Teichmann A. , Sterry W. , Tietz H.‐J. , Lademann J. , Koch S.
Published: July 2007

Investigations concerning the penetration of topically applied drugs are the subject of a multiplicity of research, as the exact knowledge of these mechanisms is the prerequisite for the optimization of such substances. As the hair follicles represent a good long‐term reservoir for topically applied substances, it can be assumed that they also represent a reservoir for microorganisms residing on and in the skin. Therefore, the hair follicles must be seen as one main site of action for antimicrobial substances and a simple non‐invasive in vivo method for the determination of penetration of antimicrobial substances into the hair follicles. The aim of the present study was to show that differential stripping, by removing the hair follicle content selectively, represents a suitable method to demonstrate the penetration of antifungal substances into the hair follicles. The follicular casts, removed from skin areas of human volunteers, which were partially pre‐treated with brilliant green (well‐known antifungal properties), were applied on agar plates inoculated with Candida albicans. The results showed inhibited growth of C. albicans, if the follicular casts were removed from skin areas pre‐treated with brilliant green. This indicates clear evidence that brilliant green had penetrated into the hair follicles. Therefore, differential stripping represents a suitable method to determine the penetration of antifungal substances into the hair follicles, which is of clinical importance for the optimization of topical antifungal therapeutics.
Molecular study of archival fungal strains isolated from cases of lacaziosis (Jorge Lobo's disease)
Authors: Vilela Raquel , Martins Jose Eduardo Costa , Pereira Cristiane N. , Melo Natalina , Mendoza Leonel
Published: July 2007

Lacazia loboi, the aetiological agent of lacaziosis (Jorge Lobo's disease), is an uncultivated anomalous fungal microbe closely related to Paracoccidioides brasiliensis, both restricted Latin American Pathogens. Early reports suggesting that L. loboi had been isolated in pure culture from cases of lacaziosis, only added more confusion to the already confusing aetiology of this disease. These strains were later identified as unusual contaminants and some of them as P. brasiliensis. Recent phylogenetic analysis grouped L. loboi as the sister taxon to P. brasiliensis, thus it was postulated that the original P. brasiliensis strains recovered from cases of lacaziosis, could be the aetiological agent of the disease. Using molecular methodologies, we investigated the archival P. brasiliensis isolate No. 525 from a case of lacaziosis, as well as other archival isolates, identified earlier as common contaminants, all recovered from similar cases of the disease. Phylogenetic analysis, using the 18S small subunit rDNA sequences of these isolates showed that strain No. 525 was a typical P. brasiliensis isolate and the other studied strains were indeed contaminants. This study unequivocally indicates that the aetiological agent of lacaziosis is yet to be cultured.
Potent anti‐microbial activity of traditional Chinese medicine herbs against Candida species
Authors: Seneviratne C. Jayampath , Wong Ricky W. K. , Samaranayake Lakshman P.
Published: July 2007

Anti‐candidial activities of eight traditional Chinese medicinal (TCM) herbs were evaluated against six different Candida species. TCM preparations were screened for antifungal activity using a standard agar diffusion assay. Following identification of potential candidate herbs, their minimum inhibitory concentration (MIC) values were determined using the standardised NCCLS M‐27A broth microdilution assay. Among TCM herbs, Rhizoma Coptidis had potent antifungal activity against Candida glabrata, Candida krusei and Candida tropicalis, but not against Candida albicans, Candida dubliniensis and Candida parapsolosis. The MIC values of the Rhizoma Coptidis against C. glabrata, C. krusei and C. tropicalis were 50, 50 and 100 μg ml−1 respectively. We report here, for the first time, the potent antifungal activity of Rhizoma Coptidis and Cortex phellodendri Chinesis on three different non‐albicans Candida species, C. glabrata, C. krusei and C. tropicalis and hence their possible use as therapeutic agents.
Allergic bronchopulmonary aspergillosis complicating chronic obstructive pulmonary disease
Authors: Agarwal Ritesh , Srinivas Rajagopala , Jindal Surinder K.
Published: July 2007

Allergic bronchopulmonary aspergillosis (ABPA) is a well recognised entity which complicates the course of 1–2% of patients with asthma and 2–15% of cystic fibrosis. Also, current criteria generally require the presence of asthma or cystic fibrosis for recognition of ABPA. The occurrence of ABPA in conditions other than cystic fibrosis or bronchial asthma is rare. Patients with chronic obstructive pulmonary disease (COPD) have mucus hypersecretion and impaired mucociliary clearance but are not reported to develop ABPA. Herein, we report a 50‐year‐old male who presented with an exacerbation of COPD due to co‐existent ABPA. To our knowledge, this is the first report of such an association. We also speculate on mechanisms of causality and impact of ABPA on disease progression in COPD.
Chronic necrotizing pulmonary aspergillosis successfully diagnosed, treated, and followed by ultrathin bronchoscope
Authors: Nakamura Yutaro , Shirai Masahiro , Hayakawa Hiroshi , Nakano Yasukatsu , Fujita Kaoru , Suda Takafumi , Chida Kingo
Published: July 2007

We present a case of chronic necrotising pulmonary aspergillosis (CNPA) successfully diagnosed, treated and followed by ultrathin bronchoscope. A 68‐year‐old man was admitted to the hospital because of a cough and low‐grade fever. A chest computerized tomography (CT) showed cavitary infiltrates in the superior segment of the left upper lobe. Bronchoscopic examination was performed using a 2.8‐mm ultrathin bronchoscope, which could be inserted into the cavity lesion under direct vision. Biopsy specimens from a whitish intracavity lesion showed septate‐branching hyphae and cultures of the cavital washing grew Aspergillus fumigatus. Using the ultrathin bronchoscope, we instilled amphotericin B into the cavity before oral itraconazole therapy. The patient showed clinical improvement with resolution of the cavitary infiltrates on CT findings. The whitish intracavity lesion had prominently disappeared after 18 months of therapy. An ultrathin bronchoscope is useful for treating and assessing cavity lesions as well as establishing a diagnosis for CNPA patients.
Pimecrolimus induced tinea incognito masquerading as intertriginous psoriasis
Authors: Rallis Efstathios , Koumantaki‐Mathioudaki Elma
Published: July 2007

A 58‐year‐old, obese, male, army officer was presented with tinea incognito of the groin masking intertriginous psoriasis. According to his history, he had pruritic, symmetrical erythematous eruption of the groin of 2‐month duration that he treated himself by using topical pimecrolimus 1%. This medication had been prescribed for his 8‐year son’s atopic dermatitis by the paediatrician. Direct examination with potassium hydroxide preparation showed fungal hyphae and Trichophyton rubrum was isolated in culture. This is the second case of topical pimecrolimus induced tinea incognito. We also review the cutaneous disorders that tinea incognito may mimic.
A model of corrosion fatigue crack growth in ship and offshore steels
Authors: JAKUBOWSKI M.
Published: July 2007

A model describing corrosion fatigue crack growth rate da/dNhas been proposed. The crack growth rate is assumed to be proportional to current flowing through the electrolyte within the crack during a loading cycle. The Shoji formula for the crack tip strain ratehas been assumed in the model. The obtained formula for the corrosion fatigue crack growth rate is formally similar to the author's empirical formulae established previously. The different effects of ΔKand the fatigue loading frequencyfon da/dN,in region I as compared to region II of the corrosion fatigue crack growth rate characteristics can be described by a change of one parameter only: the crack tip repassivation rate exponent.
Characterization of fatigue crack initiation and growth in hybrid aluminium–graphite fibre composite laminates using image analysis
Authors: BRADSHAW ROGER D. , GUTIERREZ SARAH E.
Published: July 2007

Hybrid aluminum–graphite‐epoxy fibre–metal laminates have been tested in open hole tension–tension fatigue at several stress levels. Crack initiation and growth in the outer aluminum layers was monitored by periodic digital imaging of the specimen surface. Image analysis was used to determine the crack length throughout the experiment. Crack growth results were consistent between specimens for each test configuration. A relationship between the crack growth results and stress level was developed using linear elastic fracture mechanics; this successfully characterized the data. The effect of shot peening and alternate hole finishing techniques were considered for fatigue behaviour improvement.
Predicting the J integral fracture toughness of Al 6061 using the small punch test
Authors: BUDZAKOSKA E. , CARR D. G. , STATHERS P. A. , LI H. , HARRISON R. P. , HELLIER A. K. , YEUNG W. Y.
Published: July 2007

The 6000 series aluminium alloys (Al–Mg–Si systems) are commonly used as medium‐strength structural materials; in particular, the 6061 (Al–1Mg–0.6Si) alloy is widely utilized as a general‐purpose structural material due to its excellent formability and corrosion‐resisting capabilities. The objective of this study was to obtain a correlation between the small punch (SP) test estimated equivalent fracture strain (ɛqf) and fracture toughness (J1C) property for 6061 aluminium, and determine its viability as a non‐destructive fracture toughness test technique for remaining life assessment of in‐service components. Samples of 6061‐T6 aluminium were cut from bulk plate, in both the longitudinal and transverse directions, for the as‐received condition as well as subjected to three different over‐ageing heat‐treatment schedules. A strong linear correlation between valid J1C and SP estimated biaxial fracture strain ɛqf is presented for aluminium 6061 at room temperature.