bluuebunny/crossref_metadata_2025 huggingface dataset:
Bacteriophage-mediated competition in
Bordetella
bacteria
Authors: Joo Jaewook , Gunny Michelle , Cases Marisa , Hudson Peter , Albert Réka , Harvill Eric
Published: March 2006

Apparent competition between species is believed to be one of the principal driving forces that structure ecological communities, although the precise mechanisms have yet to be characterized. Here we develop a model system that isolates phage-mediated interactions by neutralizing resource competition with a large excess of nutrients, and consists of two genetically identical
Bordetella
strains that differ only in that one is the carrier of phage and the other is susceptible to the phage. We observe and quantify the competitive advantage of the bacterial strain bearing the prophage in both invading and in resisting invasion by the bacterial strain sensitive to the phage, and use our experimental measurements to develop a mathematical model of phage-mediated competition. The model predicts, and experimental evidence confirms, that the competitive advantage conferred by the lysogenic phage depends only on the phage pathology on the sensitive bacterial strain and is independent of other phage and host parameters, such as the infection-causing contact rate, the spontaneous and infection-induced lysis rates and the phage burst size. This work combines experimental and mathematical approaches to the study of phage-driven competition, and provides an experimentally tested framework for evaluation of the effects of pathogens/parasites on interspecific competition.
Division of labour and colony efficiency in social insects: effects of interactions between genetic architecture, colony kin structure and rate of perturbations
Authors: Waibel Markus , Floreano Dario , Magnenat Stéphane , Keller Laurent
Published: March 2006

The efficiency of social insect colonies critically depends on their ability to efficiently allocate workers to the various tasks which need to be performed. While numerous models have investigated the mechanisms allowing an efficient colony response to external changes in the environment and internal perturbations, little attention has been devoted to the genetic architecture underlying task specialization. We used artificial evolution to compare the performances of three simple genetic architectures underlying within-colony variation in response thresholds of workers to five tasks. In the ‘deterministic mapping’ system, the thresholds of individuals for each of the five tasks is strictly genetically determined. In the second genetic architecture (‘probabilistic mapping’), the genes only influence the probability of engaging in one of the tasks. Finally, in the ‘dynamic mapping’ system, the propensity of workers to engage in one of the five tasks depends not only on their own genotype, but also on the behavioural phenotypes of other colony members. We found that the deterministic mapping system performed well only when colonies consisted of unrelated individuals and were not subjected to perturbations in task allocation. The probabilistic mapping system performed well for colonies of related and unrelated individuals when there were no perturbations. Finally, the dynamic mapping system performed well under all conditions and was much more efficient than the two other mapping systems when there were perturbations. Overall, our simulations reveal that the type of mapping between genotype and individual behaviour greatly influences the dynamics of task specialization and colony productivity. Our simulations also reveal complex interactions between the mode of mapping, level of within-colony relatedness and risk of colony perturbations.
Host mating system and the prevalence of disease in a plant population
Authors: Koslow Jennifer M , DeAngelis Donald L
Published: March 2006

A modified susceptible–infected–recovered (SIR) host–pathogen model is used to determine the influence of plant mating system on the outcome of a host–pathogen interaction. Unlike previous models describing how interactions between mating system and pathogen infection affect individual fitness, this model considers the potential consequences of varying mating systems on the prevalence of resistance alleles and disease within the population. If a single allele for disease resistance is sufficient to confer complete resistance in an individual and if both homozygote and heterozygote resistant individuals have the same mean birth and death rates, then, for any parameter set, the selfing rate does not affect the proportions of resistant, susceptible or infected individuals at equilibrium. If homozygote and heterozygote individual birth rates differ, however, the mating system can make a difference in these proportions. In that case, depending on other parameters, increased selfing can either increase or decrease the rate of infection in the population. Results from this model also predict higher frequencies of resistance alleles in predominantly selfing compared to predominantly outcrossing populations for most model conditions. In populations that have higher selfing rates, the resistance alleles are concentrated in homozygotes, whereas in more outcrossing populations, there are more resistant heterozygotes.
Parasites shape the optimal investment in immunity
Authors: Tschirren Barbara , Richner Heinz
Published: March 2006

The evolution of optimal functioning and maintenance of the immune system is thought to be driven by the costs arising from the allocation of resources to immune functions rather than to growth and reproduction and by the benefits arising from higher defence if an infection occurs. In young animals there is a high premium for fast growth and competitiveness and a parasite-mediated trade-off is thus predicted between the allocation of resources to growth versus immune function. In a field study on nestling great tits (Parus major), we manipulated simultaneously the level of immune defence by a dietary supplementation of the immunostimulant methionine and ectoparasite (Ceratophyllus gallinae) abundance in the nest and thereby assessed both the costs and benefits of investing in immune defence. Nestlings supplemented with methionine grew slower during the experimental boost of their immune system compared to controls. Thereafter, however, nestlings with a boosted immune system grew at faster rates under parasite pressure compared to unstimulated birds. It experimentally shows the costs and benefits of investment in immunity and suggests that the evolution of optimum host defence is governed by a parasite-mediated allocation trade-off between growth and immune function.
Contributions of inwardly rectifying K
+
currents to repolarization assessed using mathematical models of human ventricular myocytes
Authors: Fink Martin , Giles Wayne R , Noble Denis
Published: March 2006

Repolarization of the action potential (AP) in cardiac muscle is a major determinant of refractoriness and excitability, and can also strongly modulate excitation–contraction coupling. In clinical cardiac electrophysiology, the Q-T interval, and hence action potential duration, is both an essential marker of normal function and an indicator of risk for arrhythmic events. It is now well known that the termination of the plateau phase of the AP and the repolarization waveform involve a complex interaction of transmembrane ionic currents. These include a slowly inactivating Na
+
current, inactivating Ca
2+
current, the decline of an electrogenic current due to Na
+
/Ca
2+
exchange and activation of three or four different K
+
currents. At present, many of the quantitative aspects of this important physiological and pathophysiological process remain incompletely understood.

Recently, three mathematical models of the membrane AP in human ventricle myocyte have been developed and made available on the Internet. In this study, we have implemented these models for the purpose of comparing the K
+
currents, which are responsible for terminating the plateau phase of the AP and generating its repolarization. In this paper, our emphasis is on the two highly nonlinear inwardly rectifying potassium currents,

and

. A more general goal is to obtain improved understanding of the ionic mechanisms, which underlie all-or-none repolarization and the parameter denoted ‘repolarization reserve’ in the human ventricle. Further, insights into these fundamental variables can be expected to provide a more rational basis for clinical assessment of the Q-T and Q-T
C
intervals, and hence provide insights into some of the very substantial efforts in safety pharmacology, which are based on these parameters.
Modelling the onset of Type 1 diabetes: can impaired macrophage phagocytosis make the difference between health and disease?
Authors: Marée Athanasius F.M , Kublik Richard , Finegood Diane T , Edelstein-Keshet Leah
Published: March 2006

A wave of apoptosis (programmed cell death) occurs normally in pancreatic β-cells of newborn mice. We previously showed that macrophages from non-obese diabetic (NOD) mice become activated more slowly and engulf apoptotic cells at a lower rate than macrophages from control (Balb/c) mice. It has been hypothesized that this low clearance could result in secondary necrosis, escalating inflammation and self-antigen presentation that later triggers autoimmune, Type 1 diabetes (T1D). We here investigate whether this hypothesis could offer a reasonable and parsimonious explanation for onset of T1D in NOD mice. We quantify variants of theCopenhagen model(Freiesleben De Blasioet al. 1999Diabetes48, 1677), based on parameters from NOD and Balb/c experimental data. We show that the original Copenhagen model fails to explain observed phenomena within a reasonable range of parameter values, predicting an unrealistic all-or-none disease occurrence for both strains. However, if we take into account that, in general, activated macrophages produce harmful cytokinesonlywhen engulfing necrotic (but not apoptotic) cells, then the revised model becomes qualitatively and quantitatively reasonable. Further, we show that known differences between NOD and Balb/c mouse macrophage kinetics are large enough to account for the fact that an apoptotic wave can trigger escalating inflammatory response in NOD, but not Balb/c mice. In Balb/c mice, macrophages clear the apoptotic wave so efficiently, that chronic inflammation is prevented.
Multi-symptom illnesses, unexplained illness and Gulf War Syndrome
Authors: Ismail Khalida , Lewis Glyn
Published: March 2006

Explanatory models for the increased prevalence of ill health in Gulf veterans compared to those not deployed to the Gulf War 1990–1991 remain elusive. This article addresses whether multi-symptom reporting in Gulf veterans are types of medically unexplained symptoms and whether the alleged Gulf War Syndrome is best understood as a medically unexplained syndrome. A review of the epidemiological studies, overwhelmingly cross-sectional, describing ill health was conducted including those that used factor analysis to search for underlying or latent clinical constructs. The overwhelming evidence was that symptoms in Gulf veterans were either in keeping with currently defined psychiatric disorders such as depression and anxiety or were medically unexplained. The application of factor analysis methods had varied widely with a risk of over interpretation in some studies and limiting the validity of their findings. We concluded that ill health in Gulf veterans and the alleged Gulf War Syndrome is best understood within the medically unexplained symptoms and syndromes constructs. The cause of increased reporting in Gulf veterans are still not clear and requires further inquiry into the interaction between sociological factors and symptomatic distress.
Stress and stressors of the early phases of the Persian Gulf War
Authors: Gifford Robert K , Ursano Robert J , Stuart John A , Engel Charles C
Published: March 2006

Soldiers who deployed to Saudi Arabia in support of Operation Desert Shield were exposed to a wide variety of stressors. These stressors from the pre-combat phase of the deployment undoubtedly affect the current health of Gulf War veterans, but the exact mechanisms and linkages are not known. This article examines the nature of those stressors and possible effects on later health of veterans.
Gulf War illness: a view from Australia
Authors: Sim Malcolm , Kelsall Helen
Published: March 2006

Australia sent a small, mostly naval, deployment to the 1991 Gulf War. When papers and media concerns arose about unexplained Gulf War illnesses in Gulf War troops from other countries, Australia decided to undertake its own study of Australian veterans. Undertaking a later study, more than 10 years after the Gulf War, allowed us to incorporate some methodological improvements on previous research, such as the inclusion of a face-to-face health assessment where more objective health data could be collected in addition to using a postal questionnaire. Despite the different Gulf War experience for the mostly naval Australian group, there were remarkable consistencies in the patterns of multiple symptom reporting found in overseas studies, including the fact that no unique symptom clusters were identified. In general, this excess symptom reporting was not found to occur with excesses in more objective measures of physical health. These objective physical measures included a wide range of haematological, biochemical and serological markers, a physical examination, spirometry and a step test of fatigability. In contrast, several psychological disorders, including anxiety, post-traumatic stress disorder, depression and substance abuse, were found to occur in excess in the Australian Gulf War group and were associated with Gulf War psychological stressors. These findings have helped raise awareness in Australia of psychological health problems in deployed military personnel.
Depleted uranium exposure and health effects in Gulf War veterans
Authors: Squibb Katherine S , McDiarmid Melissa A
Published: March 2006

Health effects stemming from depleted uranium (DU) exposure in a cohort of Gulf War veterans who were in or on US Army vehicles hit by friendly fire involving DU munitions are being carefully monitored through the Baltimore Veterans Affairs (VA) DU Follow-Up Program initiated in 1993. DU exposure in this cohort has been directly measured using inductively coupled plasma-mass spectrometer (ICP-MS) isotopic analysis for DU in urine specimens. Soldiers with embedded DU fragments continue to excrete elevated concentrations of U in their urine, documenting ongoing systemic exposure to U released from their fragments. Biennial surveillance visits provide a detailed health assessment that includes basic clinical measures and surveillance for early changes in kidney function, an expected target organ for U. Tests also include measurements of genotoxicity and neuroendocrine, neurocognitive and reproductive function. With the exception of the elevated urine U excretion, no clinically significant expected U-related health effects have been identified to date. Subtle changes in renal function and genotoxicity markers in veterans with urine U concentrations greater than 0.1 μg
−1
creatinine, however, indicate the need for continued surveillance of these DU-exposed veterans.
Toxicological assessments of Gulf War veterans
Authors: Brown Mark
Published: March 2006

Concerns about unexplained illnesses among veterans of the 1991 Gulf War appeared soon after that conflict ended. Many environmental causes have been suggested, including possible exposure to depleted uranium munitions, vaccines and other drugs used to protect troops, deliberate or accidental exposure to chemical warfare agents and pesticides and smoke from oil-well fires. To help resolve these issues, US and UK governments have sought independent expert scientific advice from prestigious, independent scientific and public health experts, including the US National Academies of Science and the UK Royal Society and Medical Research Council. Their authoritative and independent scientific and medical reviews shed light on a wide range of Gulf War environmental hazards. However, they have added little to our understanding of Gulf War veterans' illnesses, because identified health effects have been previously well characterized, primarily in the occupational health literature. This effort has not identified any new health effects or unique syndromes associated with the evaluated environmental hazards. Nor do their findings provide an explanation for significant amounts of illnesses among veterans of the 1991 Gulf War. Nevertheless, these independent and highly credible scientific reviews have proven to be an effective means for evaluating potential health effects from deployment-related environmental hazards.
Risk and the social construction of ‘Gulf War Syndrome’
Authors: Durodié Bill
Published: March 2006

Fifteen years since the events that are held by some to have caused it, Gulf War Syndrome continues to exercise the mind and energies of numerous researchers across the world, as well as those who purport to be its victims and their advocates in the media, law and politics.

But it may be that the search for a scientific or medical solution to this issue was misguided in the first place, for Gulf War Syndrome, if there is such an entity, appears to have much in common with other ‘illnesses of modernity’, whose roots are more socially and culturally driven than what doctors would conventionally consider to be diseases.

The reasons for this are complex, but derive from our contemporary proclivity to understand humanity as being frail and vulnerable in an age marked by an exaggerated perception of risk and a growing use of the ‘politics of fear’. It is the breakdown of social solidarities across the twentieth century that has facilitated this process.

Unfortunately, as this paper explores, our inability to understand the social origins of self-hood and illness, combined with a growing cynicism towards all sources of authority, whether political, scientific, medical or corporate, has produced a powerful demand for blame and retribution deriving from a resolute few who continue to oppose all of the evidence raised against them.

Sadly, this analysis suggests that Gulf War Syndrome is likely to prove only one of numerous such instances that are likely to emerge over the coming years.
On being a Gulf veteran: an anthropological perspective
Authors: Kilshaw Susie
Published: March 2006

There is no doubt that Gulf service has affected the well-being of some of the members of the UK armed forces who served in that conflict, yet the reason for this remain unclear. At present, the debate surrounding Gulf War Syndrome (GWS) has become stagnant and highly polarized. This paper argues that a new perspective is needed to further improve our understanding of the problem and suggests that the methods and theories of anthropology, with its focus on nuances and subtleties, can provide new insights. Data were generated from 14 months of ethnographic fieldwork in the UK including participant observation, semi-structured interviews and document analysis. Anthropology provides a unique way of approaching and understanding somatic symptoms and suggests that GWS symptom reporting can be seen as a form of communication. The work focuses on the sufferers' accounts, the symptoms themselves and the context within which we find them in order to better understand what was being expressed and commented upon. Although necessary to contextualize GWS through situating it among other emergent illnesses and widespread health beliefs, this paper shows there is a need to bring back the particular. This work seeks to make sense of the cultural circumstances, specific and general, which gave rise to the illness.
Managing future Gulf War Syndromes: international lessons and new models of care
Authors: Engel Charles C , Hyams Kenneth C , Scott Ken
Published: March 2006

After the 1991 Gulf War, veterans of the conflict from the United States, United Kingdom, Canada, Australia and other nations described chronic idiopathic symptoms that became popularly known as ‘Gulf War Syndrome’. Nearly 15 years later, some 250 million dollars in United States medical research has failed to confirm a novel war-related syndrome and controversy over the existence and causes of idiopathic physical symptoms has persisted. Wartime exposures implicated as possible causes of subsequent symptoms include oil well fire smoke, infectious diseases, vaccines, chemical and biological warfare agents, depleted uranium munitions and post-traumatic stress disorder. Recent historical analyses have identified controversial idiopathic symptom syndromes associated with nearly every modern war, suggesting that war typically sets into motion interrelated physical, emotional and fiscal consequences for veterans and for society. We anticipate future controversial war syndromes and maintain that a population-based approach to care can mitigate their impact. This paper delineates essential features of the model, describes its public health and scientific underpinnings and details how several countries are trying to implement it. With troops returning from combat in Afghanistan, Iraq and elsewhere, the model is already getting put to the test.
Multiple mucinous and lipomatous variant of eccrine angiomatous hamartoma associated with spindle cell hemangioma: a novel collision tumor?
Authors: Lee Hae‐Woong , Han Seung‐Seog , Kang Jun , Lee Mi‐Woo , Choi Jee‐Ho , Moon Kee‐Chan , Koh Jai‐Kyoung
Published: March 2006

Abstract:  Eccrine angiomatous hamartoma (EAH) is a rare, benign condition characterized histologically by increased numbers of eccrine elements, as well as numerous capillary channels. In most cases, EAH arises as a single lesion; however, multiple variants have been reported. We report a 35‐year‐old female patient with multiple, sudoriparous, subcutaneous nodules on the right foot, which showed typical histopathological findings of EAH, and vascular components of the tumor consisted of thin‐walled dilated vascular spaces intermixed with spindle cells and some histiocytoid endothelial cells representing spindle cell hemangioma (SCH). To our knowledge, the co‐existence of EAH with SCH is a novel finding and not yet described.
Cutaneous neuroendocrine adenoma: an uncommon neoplasm
Authors: Mahalingam M. , Kveaton J. F. , Bhawan J.
Published: March 2006

Background:  Cutaneous neuroendocrine neoplasms are typically malignant. Benign cutaneous neuroendocrine tumors are uncommon.

Methods:  We report the case of a 32‐year‐old female who presented with a granular mass in the right external auditory canal.

Results:  Microscopic examination of a shave biopsy revealed a poorly circumscribed neoplasm with glandular differentiation. While cytologic atypia and mitotic activity were not evident, pagetoid spread was observed. Immunohistochemistry was indicative of neuroendocrine origin.

Conclusions:  This case report of neuroendocrine adenoma indicates that this entity should be entertained in the repertoire of conditions affecting the external ear.
Signal transduction of inflammatory cytokines and tumor development
Authors: Yoshimura Akihiko
Published: March 2006

It has been estimated that >20% of all malignancies are initiated or exacerbated by inflammation. Until recently, the molecular basis of this process has not been clarified. However, recent studies have uncovered the molecular mechanism of intracellular signaling pathways of inflammatory cytokines such as tumor necrosis factor (TNF)‐α, interferon (IFN)‐γ and interleukin (IL)‐6. Three major transcription factors including NF‐κB, STAT1 and STAT3 have been shown to play major roles in transmitting inflammatory cytokine signals to the nucleus. One function of NF‐κB and STAT3 in tumor cells is the promotion of cell growth and cell survival through the induction of target genes, whose products promote cell division and inhibit apoptosis. In addition, NF‐κB and STAT1 are important transcription factors that induce inflammatory mediators from inflammatory cells, especially macrophages, while STAT3 often antagonizes this process. STAT1 is generally believed to be an anti‐oncogene because it promotes apoptosis through p53, but it could promote inflammation‐mediated tumor development by enhancing tissue injury, remodeling, fibrosis and inflammation. Hence, the inhibition of NF‐κB and STATs offers a strategy for treatment of a variety of malignancies and can convert inflammation‐induced tumor growth into inflammation‐induced tumor regression. (Cancer Sci 2006; 97)
Recent trends in the treatment of advanced lung cancer
Authors: Saijo Nagahiro
Published: March 2006

Lung cancer is one of the major causes of death in many countries because of high rates of smoking, especially in Asian countries. Lung cancer is divided into two major categories based on their biological characteristics and the selection of treatment methods: non‐small cell lung cancer (NSCLC; 85%) and small cell lung cancer (15%). Early detection and complete resection are very important in NSCLC, but the cure rate is not very high, except in stage 1A disease. It is extremely important to understand the biology of lung cancer and to introduce more effective treatments in order to improve the survival of NSCLC patients. Numerous clinical trials involving lung cancer patients have led to ‘state‐of‐the‐art’ treatments for each stage of the disease. Progress in chemotherapy and molecular target based therapy have altered the standard therapy for NSCLC. (Cancer sci 2006; 97)
Orotate phosphoribosyltransferase levels measured by a newly established enzyme‐linked immunosorbent assay in gastric carcinoma
Authors: Sakurai Yoichi , Sakamoto Kazuki , Sugimoto Yoshikazu , Yoshida Ikuo , Masui Toshihiko , Tonomura Shuhei , Inaba Kazuki , Shoji Mitsutaka , Nakamura Yasuko , Uyama Ichiro , Komori Yoshiyuki , Ochiai Masahiro , Matsuura Shiro , Tanaka Hideyuki , Oka Toshinori , Fukushima Masakazu
Published: March 2006

A number of enzymes have been shown to be involved in the process of activation and/or degradation of 5‐fluorouracil (5‐FU), and are potential candidates for predicting chemosensitivity to 5‐FU. Among these, orotate phosphoribosyltransferase (OPRT EC 2.4.2.10) is a key enzyme related to the first‐step activation process of 5‐FU and has been shown to be an important enzyme that helps to predict sensitivity to 5‐FU and its related derivatives. We developed a new enzyme‐linked immunosorbent assay (ELISA) to accurately assess intratumoral activity of OPRT. A new sandwich ELISA was established using anti‐OPRT polyclonal antibodies obtained from the rabbit immunized with the recombinant human peptides of the OPRT molecule. OPRT levels were measured in eight human cancer xenografts and in 75 gastric cancer tissues using both a newly established ELISA and a conventional enzyme assay, using radiolabeled 5‐FU as a substrate. There was a significant correlation between OPRT levels measured by this ELISA and OPRT enzyme activity the in eight human cancer xenografts (r2 = 0.782) and gastric carcinoma tissue (r2 = 0.617). The ELISA system for OPRT requires a minimal amount of carcinoma tissue, making it an easy‐to‐use assay system to predict sensitivity to 5‐FU and its derivatives in gastric carcinoma. There was a significant correlation between tumor growth inhibition rates against the oral administration of oral‐uracil/tegafur (UFT) and OPRT enzyme activity in the human cancer xenografts (r2 = 0.574). These results suggest that this newly developed sandwich ELISA system for the quantification of OPRT levels is technically simple, feasible and a useful tool to predict sensitivity to fluoropyrimidine‐based anticancer chemotherapy in patients with gastric carcinoma and other cancers. (Cancer Sci 2006; 97)
Notes on the distribution and abundance of the caecilian Boulengerula uluguruensis (Amphibia: Gymnophiona: Caeciliidae) in the Uluguru Mountains, Tanzania
Authors: John Measey G. , Mejissa John , Müller Hendrik
Published: March 2006

Boulengerula uluguruensis is a terrestrial caeciliid caecilian described from the Uluguru Mountains of Tanzania. We investigated the relative abundance of B. uluguruensis in agricultural and forested habitats at the beginning of the rainy season. This caecilian was found over a wide altitudinal range (450–1175 m a.s.l.), and in many land cover types (including natural forest, plantation forest and small scale agriculture), and different soil textures (including very compact soil). Based on quantitative and semi‐quantitative surveys, B. uluguruensis is more abundant than any other subterranean lower vertebrate in this area, with densities up to 0.4 individuals m−2 in some agricultural plots. The hypothesis proposed, that B. uluguruensis is more abundant in agriculture than their native forest, could not be conclusively tested during this brief visit, although the data that were collected do not indicate to the contrary. Likewise, the size of animals from forest and agricultural populations could not be objectively compared.
Some biological aspects and life history strategies of Nile tilapia Oreochromis niloticus (L.) in Lake Victoria, Kenya
Authors: Njiru M. , Ojuok J. E. , Okeyo‐Owuor J. B. , Muchiri M. , Ntiba M. J. , Cowx I. G.
Published: March 2006

The life history characteristics of introduced Nile tilapia (Oreochromis niloticus L.) in Lake Victoria, including, sex ratio, fecundity, reproduction, weight‐length relationship and body condition were studied and compared with those of other populations. Samples were collected by trawling and seining in the Kenyan sector of Lake Victoria between June 1998 and December 2000. Males predominated over females (sex ratio 1.42 : 1 : 00). O. niloticus spawned throughout the year but with a peak between December and June. Length at first maturity was (mean ± SD) 30.81 ± 0.09 for females and 34.5 ± 6 0.48 for males. There was little seasonal variation in relative condition, which ranged from 0.92 to 1.05 in males and 0.94 to 1.07 in females. Gonadosomatic index (GSI) was low during the postspawning period (July to October) and high during the protracted breeding period (December and June). Fecundity ranged from 905 to 7619 oocytes for fish of 28 to 51 cm total length (TL) respectively. The relationships between fecundity (F) and total length (L), weight (W) and ovary weight (OW) were: F = 8.159L1.53, F = 96.269W0.4504, F = 1806 + 39.4OW. The slope b of the weight‐length relationship was 3.08–3.32 for males and 3.07–3.22 for females. Growth was allometric in both cases and was significantly different from the expected value of 3. The life history strategy of O. niloticus is discussed in context of environmental changes occurring in the lake.
Patterns of den occupation by the spotted hyaena (Crocuta crocuta)
Authors: Boydston Erin E. , Kapheim Karen M. , Holekamp Kay E.
Published: March 2006

Spotted hyaenas utilize isolated natal dens (NDs) and communal dens (CDs) for rearing their cubs. Here we describe patterns of natal and CD occupation by hyaenas belonging to one well‐studied clan in the Maasai Mara National Reserve during a 10‐year period. Locations of 98 den sites that were used as natal or CDs by hyaenas in the study clan were digitized in a Geographic Information System, and the duration of use of each den site, frequency of re‐use, and distances involved in den moves were quantified. Hyaenas moved their CD monthly on average. Most CD sites were occupied only once during the study, but several sites were used repeatedly. On rare occasions, the movement of hyaenas to a new den site could be attributed to a disturbance event at the CD, but factors regularly prompting hyaenas to move to new CD sites were unclear. High‐ranking female hyaenas were more likely to rear their cubs from birth in a CD than low‐ranking females. Low‐ranking females almost always utilized isolated NDs for the first few weeks of a litter's development, and low‐ranking females transferred their cubs over longer distances than did high‐ranking females.
A possible role for CCL27/CTACK‐CCR10 interaction in recruiting CD4+ T cells to skin in human graft‐versus‐host disease
Authors: Faaij Claudia M. J. M. , Lankester Arjan C. , Spierings Eric , Hoogeboom Manja , Bowman Edward P. , Bierings Marc , Révész Tom , Egeler R. Maarten , Van Tol Maarten J. D. , Annels Nicola E.
Published: March 2006

Graft‐versus‐host disease (GvHD) is a serious complication of allogeneic stem cell transplantation (SCT) affecting the skin, gut and liver. The involvement of distinct organs suggests a role for tissue‐specific chemokines and their receptors in directing activated donor T cells to these sites. In this study the potential involvement of the skin‐specific CCL27/CTACK‐CCR10 interaction was investigated in 15 paediatric SCT patients with skin GvHD. During the course of skin GvHD, peripheral blood T cells from these patients contained a high proportion of CD4+ CCR10+ T cells that disappeared after the GvHD was resolved. These cells were CD45RO+, expressed additional skin homing markers (cutaneous lymphocyte‐associated antigen and CCR4), and produced the T‐cell helper type 1‐cytokines tumour necrosis factor‐alpha and interleukin‐2. The increase in CD4+ CCR10+ T cells was absent in SCT patients without GvHD. Immunohistochemical investigations showed CD4+ CCR10+ T cells in the GvHD skin biopsies of the same patients, but not in the gut biopsies of patients also suffering from gut GvHD. The infiltration of CD4+ CCR10+ T cells in the GvHD‐affected skin correlated with an enhanced epidermal expression of CCL27/CTACK, the ligand for CCR10. These findings support the involvement of CCL27/CTACK‐CCR10 interaction in recruiting CD4+ T cells to the skin, thus contributing to the pathogenesis of acute GvHD.
Somatic hypermutation and VH gene usage in hairy cell leukaemia
Authors: Arons Evgeny , Sunshine Joel , Suntum Tara , Kreitman Robert J.
Published: March 2006

To examine the usage and mutational status of VH genes in hairy cell leukaemia (HCL), we analysed 24 immunoglobulin heavy chain (IgH) sequences expressed in 23 patients. None had premature stop codons. VH3‐23 was the most common gene and a VH6 gene was observed for the first time in HCL. Although the mean mutation frequency was 6·1%, slightly higher than in previous HCL series, four patients had 99·6–100% homology to germline sequences, three of whom had high tumour burdens and poor outcomes. Despite the high mutation frequency, only two of 24 rearrangements had clear statistical evidence of antigen‐dependent somatic mutation. Our results increase the database of reported functional HCL rearrangements to 94 in 92 patients. Overall, both gene usage and mutation frequency are very similar to mucosa‐associated lymphoid tissue‐type marginal zone lymphoma. The data are consistent with HCL originating from post‐germinal centre marginal zone B cells, although the heterogeneity observed suggests that HCL may originate differently in some patients, and this could have implications for prognosis and treatment.
Distinguishing between type 2B and pseudo‐von Willebrand disease and its clinical importance
Authors: Enayat Mohammad S. , Guilliatt Andrea M. , Lester William , Wilde Jonathan T. , Williams Michael D. , Hill Frank G.H.
Published: March 2006

Pseudo‐von Willebrand disease (p‐VWD) and type 2B von Willebrand disease (VWD) have similar phenotypic parameters and clinical symptoms, but different aetiologies. Fourteen individuals from five families with a historical diagnosis of type 2B VWD but with no mutation in the von Willebrand factor gene were re‐investigated for the possibility of p‐VWD, using platelet aggregation in the presence of cryoprecipitate. p‐VWD was confirmed by targeted DNA sequencing of the glycoprotein Ibα gene, identifying a heterozygous Glycine 233 Valine substitution. This study suggests that p‐VWD may be under diagnosed, and that platelet aggregation in the presence of cryoprecipitate is useful in differentiating this disorder from type 2B VWD.
Toll‐like receptor ligands as adjuvants in allergen‐specific immunotherapy
Authors: Johansen P. , Senti G. , Martinez Gomez J. M. , Storni T. , von Beust B. R. , Wüthrich B. , Bot A. , Kündig T. M.
Published: March 2006

Background
Allergen‐specific immunotherapy (SIT) leads to long‐term amelioration of T‐helper type 2 (Th2)‐mediated allergic symptoms and is therefore recommended as a first line therapy for allergies. The major disadvantage of SIT is its low efficiency, requiring treatment over years.

Objective
In this study, we evaluated the potential of Toll‐like receptor (TLR) ligands to facilitate Th1‐type immune responses.

Methods
The immunogenicity and therapeutic potential of the major bee venom allergen phospholipase A2 (PLA2) combined with various TLR ligands were tested in mice and compared with immune responses induced by conventional aluminium‐based preparations.

Results
Regarding total IgG against PLA2, TLR2/4‐binding lipopolysaccharide and TLR3‐binding polyriboinosinic polyribocytidylic (PolyI:C) were the superior adjuvants for prophylactic vaccination. However, TLR9‐binding phosphorothioate‐modified cytosine–guanosine‐rich oligonucleotide (CpG), TLR‐3‐binding PolyI:C, and TLR2/6‐binding peptidoglycan skewed the immune responses more towards IgG2a isotype and Th1 cytokines. Furthermore, in a therapeutic approach, CpG, PolyI:C and TLR7/8‐binding 3M003 had immune modulating properties as they suppressed established IgE titres.

Conclusion
The potential of TLR ligands to adjuvate the immunogenicity of bee venom PLA2 and to skew the Th1–Th2 balance proved very heterogeneous. With respect to SIT, CpG, PolyI:C, and 3M003 were very promising. Hence, TLR ligands should be considered as adjuvants or immune modulators in SIT in human as to improve its efficiency regarding the Th1–Th2 balance of the immune response with a likely effect on therapy duration.
ADAM33 polymorphisms are associated with asthma susceptibility in a Japanese population
Authors: Noguchi E. , Ohtsuki Y. , Tokunaga K. , Yamaoka‐Sageshima M. , Ichikawa K. , Aoki T. , Shibasaki M. , Arinami T.
Published: March 2006

Background
Asthma is the most common chronic disorder in childhood, and asthma exacerbation is an important cause of childhood morbidity and hospitalization. Asthma is believed to be a complex disorder involving genetic and environmental factors, and several asthma susceptibility loci have been identified through genome‐wide screening. A disintegrin and metalloprotease 33 (ADAM33) was the first asthma susceptibility gene to be discovered by positional cloning in 2002.

Objective
The aim of the present study was to investigate whether single‐nucleotide polymorphisms (SNPs) in ADAM33 are associated with childhood asthma in the Japanese population.

Methods
Twenty‐three ADAM33 SNPs were genotyped by fluorescence correlation spectroscopy with the use of DNA from 155 families (538 members) identified through children with atopic asthma. The transmission disequilibrium test (TDT) was performed for family‐based association study.

Results
TDT revealed that minor alleles of S+1, ST+4, and T2 SNPs were over‐transmitted to asthma‐affected offspring (P<0.05). According to the haplotype TDT, no haplotype of ADAM33 was transmitted preferentially to asthmatic offspring.

Conclusion
Our results confirm the involvement of ADAM33 in the development of childhood asthma among the Japanese.
Abundance and primary production of filamentous green algae Zygogonium ericetorum in an extremely acid (pH 2.9) mining lake and its impact on alkalinity generation
Authors: KLEEBERG ANDREAS , SCHUBERT HENDRIK , KOSCHORRECK MATTHIAS , NIXDORF BRIGITTE
Published: March 2006

1. In extremely acid mining lakes, benthic filamentous green algae (Zygnemataceae, Chlorophyta) thrive as effective competitors for limited carbon (C). These algae could supply C for microbial‐mediated benthic alkalinity generation. However, biomass, productivity and impact of the acidobiontic filamentous green algae at pH ≤3 have not previously been determined.

2. Periphytic filamentous green algae was mapped by harvesting their biomass from 85 1 × 1 m quadrats in mining lake Grünewalder Lauch. Zygogonium ericetorum colonised water depths between 1.6 and 10.5 m covering 88% of total area. Biomass peaked at 5–6 m depth. Total Zygogonium biomass amounted to 72.2 t dry weight for the whole lake (0.94 km2), which corresponds to 16.1 t C and the accumulation of primary production from 2.2 years.

3. Growth of Zygogonium is moderately N, C and extremely P deficient, and seriously stressed by high rates of Fe deposition during summer. Consequently, net primary production (NPP) of Zygogonium, calculated from measured photosynthesis versus irradiance characteristics and calculated underwater irradiance (0.13 g C m−2 year−1) and in situ oxygen measurements (7.8 g C m−2 year−1), corresponds to only 0.3% and 18.1% of pelagic NPP.

4. Neither pelagic nor benthic Zygogonium primary production can supply enough C for efficient acidity removal. However, at rates of benthic NPP in summer of 21.4 mg C m−2 day−1, Zygogonium contributed 26% of the C equivalents to remove acidity associated with ferric iron, contributing at least seasonally to efficient alkalinity generation.
Analysis of expressed sequence tags from Rhynchosciara americana salivary glands
Authors: Siviero F. , Rezende‐Teixeira P. , Andrade A. , Machado‐Santelli G. M. , Santelli R. V.
Published: March 2006

The diptera Rhynchosciara americana (sciaridae) is an important model organism in polyteny and gene amplification research, but up to now a limited amount of data regarding DNA sequences and molecular aspects of this species is available. Considering the importance of going further on the DNA puffs biological meaning, we proposed to generate EST sequences from a DNA library constructed from salivary glands. After their categorization in gene ontology terms, they were used to construct an ‘electronic Northern’ that represents a general view of the salivary gland metabolic status in an important phase of larval development: the spinning of communal cocoon. In this phase occurs the last polytene DNA replication cycle concomitantly with the specific loci amplification related to protein secretion.
Immulectin‐4 from the tobacco hornworm Manduca sexta binds to lipopolysaccharide and lipoteichoic acid
Authors: Yu X.‐Q. , Ling E. , Tracy M. E. , Zhu Y.
Published: March 2006

Insect C‐type lectins function as pattern recognition receptors in innate immunity. In the tobacco hornworm Manduca sexta, we have previously isolated three C‐type lectins named immulectins, which are involved in innate immune responses. Here, we report a new member of the immulectin family, immulectin‐4 (IML‐4). IML‐4 mRNA was detected in the fat body of control larvae and was induced in the fat body when larvae were injected with bacteria. Recombinant IML‐4 bound to bacterial lipopolysaccharide (LPS) and lipoteichoic acid (LTA), and the binding activity was not affected by addition of calcium or EGTA. IML‐4 agglutinated bacteria and yeast, and agglutination of Escherichia coli by IML‐4 was concentration‐ and calcium‐dependent. IML‐4 also enhanced haemocyte encapsulation and melanization.
Biochemical characterization of Drosophilaγ‐glutamyl carboxylase and its role in fly development
Authors: Bandyopadhyay P. K. , Clark K. , Stevenson B. J. , Rivier J. E. , Olivera B. M. , Golic K. G. , Rong Y. S.
Published: March 2006

To investigate structure‐function relationships in γ‐glutamyl carboxylases, the enzyme from Drosophila melanogaster was characterized. Four cysteine residues were shown to be important determinants for enzymatic activity. Native Drosophila substrates have not yet been identified, but propeptides of human prothrombin and factor IX are recognized by the Drosophila enzyme. The presence of the propeptide region increased apparent affinity by ∼200‐fold, and mutation of a hydrophobic residue of factor IX propeptide (F‐16A) decreased carboxylation by 90%, as in the human enzyme. Substrate recognition appears to be highly conserved between the human and Drosophilaγ‐glutamyl carboxylases. Inactivation of Drosophilaγ‐glutamyl carboxylase by non‐sense mutations or insertional mutagenesis by P‐element insertion have no apparent effects on growth and fertility under laboratory conditions.
Frequencies of the pyrethroid resistance alleles of Vssc1 and CYP6D1 in house flies from the eastern United States
Authors: Rinkevich F. D. , Zhang L. , Hamm R. L. , Brady S. G. , Lazzaro B. P. , Scott J. G.
Published: March 2006

House flies were collected from four dairies in Maine, New York, North Carolina, and Florida, where high levels of resistance to permethrin have been documented. Regions of two genes, CYP6D1 and Vssc1, having alleles that confer resistance to permethrin (and other pyrethroids) were analysed from individuals at each collection site. The combinations of resistance alleles for Vssc1 and CYP6D1 were highly variable between each state. The resistance allele CYP6D1v1 was found at a high frequency (0.63–0.91) at all sites. Individuals homozygous susceptible for CYP6D1 were very rare and detected only at the dairy in Maine. In addition to the typical Vssc1 mutation responsible for resistance, kdr (L1014F), we also identified individuals with a L1014H mutation. Although house flies homozygous for the L1014H mutation had a lower level of resistance to permethrin, compared to L1014F, the H1014 resistance allele was frequently detected. No individuals with the super‐kdr allele (M918T + L1014F) were detected from the field collections. The intron 3 bp downstream of the kdr mutation was found to be extremely variable, providing an opportunity to reconstruct a phylogeny of Vssc1 alleles. Based on this analysis it appears the kdr‐his mutation had multiple evolutionary origins, but that the kdr mutation may have had a single origin. The impacts of these findings on resistance management are discussed.
Positional cloning of a cyromazine resistance gene in Drosophila melanogaster
Authors: Chen Z. , Robin C. , Damiano J. , Lydall J. , Lumb C. , Smith K. , Blasetti A. , Daborn P. J. , Heckel D. , McKenzie J. A. , Batterham P.
Published: March 2006

Cyromazine is an effective insecticide used to control dipteran insects. Its precise mode of action is yet to be determined, although it has been suggested that it interferes with the hormone system, sclerotization of the cuticle, or nucleic acid metabolism. To understand the way in which cyromazine acts, we have positionally cloned a cyromazine resistance gene fromDrosophila melanogaster. Six cyromazine resistance alleles had previously been generated by ethyl methanasulphonate treatment. Two of these failed to complement each other and here we identify them as having independent non‐sense mutations inCG32743, which is an ortholog ofSmg1of worms and mammals and encodes a phosphatidylinositol kinase‐like kinase (PIKK). RNAi experiments confirm that cyromazine resistance can be achieved by knocking downCG32743. These are the first cyromazine resistant mutations identified at the nucleotide level. In mammalsSmg1phosphorylates P53 in response to DNA damage. This finding supports the hypothesis that cyromazine interferes with nucleic acid metabolism.