bluuebunny/crossref_metadata_2025 huggingface dataset:
Root-associated fungal communities colonizing two dominant semiarid grasses: Hilaria sp. and Stipa sp.
Authors: Hutchinson Miriam , Belnap Jayne , Herrera Jose , Sinsabaugh Robert , Porras-Alfaro Andrea
Published: August 2009

We conducted a preliminary survey of the fungal communities associated with roots of Stipa hymenoides and Hilaria jamesii, two grasses native to the southwestern United States. Root samples from 10 different plants were collected at a semiarid grassland in Utah. Fungal communities were assessed using microscopic and molecular methods. Roots were cleared with KOH and stained using blue ink to visualize mycorrhizal and endophytic fungi. A total of 100 root segments were surface sterilized and plated on malt extract agar with antibiotics. Fungal endophytes were identified using nrITS primers.

Results/Conclusions

Microscopic analyses showed that all root samples from both Hillaria and Stipa were colonized by dark septate and arbuscular mycorrhizal fungi. Vesicles and hyaline hyphae also were observed in all the roots. Sclerotia, a characteristic structure of some dark septate fungi were also found. Approximately 75 fungi were isolated representing at least 45 morphotypes. Molecular identification showed that both grasses are colonized by endophytes in the orders Pleosporales, Hypocreales, and Sordariales commonly found in semiarid grasses, liverworts, and mosses.
Allergies, Asthma, and Eczema: Response to Disturbance of the Microbiota of the Newborn Gut
Authors: Wohl Debra , Curry William
Published: August 2009

Background/Question/Methods

The birth of a child may include routine use of antibiotics or a delivery by cesarean section. We applaud these medical advances for their direct benefits. However, birthing practices have been shown to disrupt the colonization of the microbial gut in newborns, which may have long term consequences on the development of a child’s immune system resulting in atopies (i.e., asthma, allergies, and eczema). Animal models and other research have been used to demonstrate that not only the presence, but also the community composition of the gut microbiota, is essential for normal immune development. Furthermore, it has been established that there are differences in the intestinal microbiota of children who have eczema, asthma, or allergies versus their non-atopic counterparts. In utero an infant persists in an environment free of microorganisms. During the birth process, as the baby moves down through the birth canal the baby encounters their first microbes and foreign substances stimulating the immune system of the mucosal surfaces. Under normal conditions, where newborns are exposed to an abundance of the maternal microbiota, microbial colonization is dominated by bacteria with fast doubling times. As bacterial numbers increase and resources are depleted, more specialized and complex communities become established.

Results/Conclusions

Although the ultimate impact of how the microbial community establishes itself within an individual is still not well understood, there is evidence that this is a highly sensitive process. Early differences in patterns of microbial colonization persist years suggesting colonization dynamics and assembly rules yield long-term differences. Therefore, it is not surprising factors, such as the duration of vaginal delivery, birthing method (e.g., cesarean, vaginal), or even receipt of peripartum antibiotics affects microbial colonization of the newborn. Consequently, it is important that we establish an understanding of the complexity of the microbial communities within the gut and how patterns of colonization based on possible disturbances may have both immediate and long term consequences.
Porcine nuclear transfer using somatic donor cells altered to express male germ cell function
Authors: Roh Sangho , Choi Hye-Yeon , Park Sang Kyu , Won Cheolhee , Kim Bong-Woo , Kim Jung-Hyun , Kang Hoin , Lee Eung-Ryoung , Cho Ssang-Goo
Published: August 2009

Recent studies reported that the direct transformation of one differentiated somatic cell type into another is possible. In the present study, we were able to modulate the cell fate of somatic cells to take on male germ cell function by introducing cell extracts derived from porcine testis tissue. Fibroblasts were treated with streptolysin O, which reversibly permeabilises the plasma membrane, and incubated with testis extracts. Our results showed that the testis extracts (TE) could activate expression of male germ cell-specific genes, implying that TE can provide regulatory components required for altering the cell fate of fibroblasts. Male germ cell function was sustained for more than 10 days after the introduction of TE. In addition, a single TE-treated cell was injected directly into the cytoplasm of in vitro-matured porcine oocytes. The rate of blastocyst formation was significantly higher in the TE-treated nuclear donor cell group than in the control cell group. The expression level of Nanog, Sox9 and Eomes was drastically increased when altered cells were used as donor nuclei. Our results suggest that TE can be used to alter the cell fate of fibroblasts to express male germ cell function and improve the developmental efficiency of the nuclear transfer porcine embryos.
Society for Reproductive Biology Founders' Lecture 2009. Preparing fertile soil: the importance of endometrial receptivity
Authors: Salamonsen Lois A. , Nie Guiying , Hannan Natalie J. , Dimitriadis Evdokia
Published: August 2009

The human endometrium is receptive for implantation of a blastocyst for only 4–5 days in each menstrual cycle. Failure of implantation is a major reason for infertility in women and the inability to achieve endometrial receptivity is responsible for much of the failure of reproductive technologies. Endometrial receptivity requires changes in the uterine luminal and glandular cells, particularly in terms of their secretory capacity and altered expression of adhesion molecules. In parallel with these changes, decidualisation (differentiation) of the endometrial stroma is initiated in women during the receptive phase, regardless of the presence of a blastocyst. Increased leucocyte numbers are also important. The microenvironments provided by the endometrium during the receptive phase and that support implantation are highly complex and constantly changing as implantation progresses. The present review provides a comprehensive overview of the cellular and molecular events of human implantation. It also summarises work from our laboratories emphasising the functional importance of proprotein convertase 6, along with key cytokines (interleukin-11, leukaemia inhibitory factor, activin A) and chemokines (including CX3CL1 and CCL14), during implantation. Of particular importance is how these mediators contribute to receptivity and how they are disturbed in infertile women. Factors that are critical for uterine receptivity may also be manipulated to provide new contraceptive strategies for women.
A strong correlation between fusogenicity and membrane insertion depth of the HIV fusion peptide
Authors: Qiang Wei , Sun Yan , Weliky David P.
Published: August 2009

Fusion between the membrane of HIV and the membrane of a host cell is a crucial step in HIV infection and is catalyzed by the binding of the fusion peptide domain (HFP) of the HIV gp41 protein to the host cell membrane. The HFP by itself induces vesicle fusion and is a useful model system to understand the fusion peptide/host cell membrane interaction. This article reports an experimental correlation between the membrane locations of different HFP constructs and their fusogenicities. The constructs were the HFP monomer with Val-2 to Glu-2 mutation (HFPmn_mut), wild type HFP monomer (HFPmn), and wild type HFP trimer (HFPtr). All constructs have predominant β sheet structure in membranes with physiologically relevant cholesterol content. HFPmn_mut does not fuse vesicles, HFPmn has moderate fusion rate, and HFPtr has the putative oligomerization state of HIV gp41 and a very rapid fusion rate. The HFP membrane locations were probed with solid-state NMR measurements of distances between labeled carbonyl (
13
CO) nuclei in the HFP backbone and lipid nuclei in the surface or interior regions of the membrane bilayer. HFPmn_mut is located at the membrane surface, HFPmn is inserted into a single membrane leaflet, and HFPtr is the most deeply inserted construct with contact with the center of the membrane. These results show a clear positive correlation between the insertion depths and the fusion activities of the HFP constructs. Other disease-causing enveloped viruses contain fusion peptides and this correlation may be a general structure-function model for these peptides.
The ubiquitin conjugation system is involved in the disassembly of cilia and flagella
Authors: Huang Kaiyao , Diener Dennis R. , Rosenbaum Joel L.
Published: August 2009

The disassembly of cilia and flagella is linked to the cell cycle and environmental cues. We have found that ubiquitination of flagellar proteins is an integral part of flagellar disassembly. Free ubiquitin and the ubiquitin-conjugating enzyme CrUbc13 are detected in flagella, and several proteins are ubiquitinated in isolated flagella when exogenous ubiquitin and adenosine triphosphatase are added, suggesting that the ubiquitin conjugation system operates in flagella. Levels of ubiquitinated flagellar proteins increase during flagellar resorption, especially in intraflagellar transport (IFT) mutants, suggesting that disassembly products are labeled with ubiquitin and transported to the cell body by IFT. Substrates of the ubiquitin conjugation system include α-tubulin (but not β-tubulin), a dynein subunit (IC2), two signaling proteins involved in the mating process, cyclic guanosine monophosphate–dependent kinase, and the cation channel polycystic kidney disease 2. Ubiquitination of flagellar proteins is enhanced early in mating, suggesting that ubiquitination also plays an active role in regulating signaling pathways in flagella.
Manuel de Falla, L'acoustique nouvelle and Natural Resonance: A Myth Exposed
Authors: Collins Chris
Published: August 2009

This article challenges two tenets of Falla scholarship: that the composer made use of a system of chord generation based on the harmonic series, and that he learnt this technique from Louis Lucas's L'acoustique nouvelle (Paris, 1854). The author demonstrates that Lucas's theories are largely unconcerned with the harmonic series and that Falla's use of ‘natural resonance’ has been misunderstood. Study of Falla's work, including manuscripts and writings (published and unpublished), reveals the true nature of Lucas's influence. Consideration is also given to Falla's role in the creation of this false orthodoxy.
‘Sing it for Me’: Posthuman Ventriloquism in Recent Popular Music
Authors: Auner Joseph
Published: August 2009

Drawing on writings concerning the cyborg and the posthuman, this article considers songs by Radiohead, Moby and others that use processed voices, digitally generated speech and sampled vocal loops. In these songs the technological sphere is made the locus of expression, while the human voices are mechanized and drained of subjectivity. These pieces – products of a rock band that relinquishes its voice to a computer, and of a ‘techno’ DJ striving to make mechanized dance music sing – can illustrate some ways musicians have used posthuman voices to chart and destabilize the boundaries of race, gender and the human.
Charles Rennett and the London Music-Sellers in the 1780s: Testing the Ownership of Reversionary Copyrights
Authors: Mace Nancy A.
Published: August 2009

As printed music became a valuable market commodity in late eighteenth-century England, it became a significant part of debates over the interpretation of the first copyright law (1710). In particular, compositions by Charles Dibdin and John Garth became the focus of several lawsuits filed by the attorney Charles Rennett challenging the traditional interpretation of the clause that granted composers a second 14 years of protection after the first had expired. These suits detail the status of music as intellectual property and offer new information about the businesses of major music-sellers like Longman & Broderip, the Thompsons and John Welcker.
Fitzcarraldo's Search for Aguirre: Music and Text in the Amazonian Films of Werner Herzog
Authors: Rogers Holly
Published: August 2009

This article explores the filmic relationship between music, text and image through an intertextual reading of Herzog's two Amazonian films, Aguirre: Wrath of God and Fitzcarraldo. When Aguirre and Fitzcarraldo encounter each other in the rainforest, 300 years apart, a complicated interplay of history and legend, truth and fiction, is initiated. Awash with magical occurrence, the forest has its own endlessly repeating soundtrack (written by Popul Vuh). The ability of both explorers to defend themselves from the forest depends on their relationship to this music: Aguirre, the earlier explorer, is deaf to the circular sound and attempts to overlay it with a written account of their journey. Fitzcarraldo, on the other hand, enters the forest equipped with a gramophone that plays Verdi arias; he comes with his own soundtrack. Comparison between the two journeys exposes the conventional uses of text/speech and music/song in film, to reveal music as the predominant driving force behind filmic narrative.
‘Everybody wants to be Pavarotti’: The Experience of Music for Performers and Audience at a Gilbert and Sullivan Festival
Authors: Pitts Stephanie E.
Published: August 2009

This article investigates the contribution that musical participation makes to people's lives by reporting on a study carried out at the International Gilbert and Sullivan Festival in August 2001 in Buxton, Derbyshire. The audience are shown to have a strong commitment to the musical genre and its preservation through live performance, whilst the performers are more likely to value membership of their society and the personal satisfaction that comes from successful performance. The festival therefore serves diverse purposes for those who attend it, and raises further questions about the interaction between social, personal and musical experience at events of this kind.
Changing Referral Trends of Acute Pancreatitis in Children: A 12‐year Single‐center Analysis
Authors: Park Alexander , Latif Sahibzada Usman , Shah Ahsan U , Tian Jianmin , Werlin Steven , Hsiao Allen , Pashankar Dinesh , Bhandari Vineet , Nagar Anil , Husain Sohail Zakiuddin
Published: August 2009

Background:

Acute pancreatitis is a painful inflammatory disorder known to occur in children. Recent reports, primarily on the basis of adult data, have suggested an increasing incidence. However, pediatric studies are limited.

Objective:

The study was performed to examine the frequency of acute pancreatitis in a pediatric population from 1994 to 2007 and to characterize etiologies by age subsets.

Patients and Methods:

In this retrospective study, cases of pancreatitis were identified by ICD‐9 codes and subjected to inclusion criteria.

Results:

Two hundred and seventy‐one cases of pancreatitis met inclusion criteria. Mean age of the subjects was 13.1 ± 5.6 years. The recurrence rate was 15.3%. Biliary disease was the most common etiology (32.6%). Acute pancreatitis cases evaluated at a single tertiary care center increased 53% between 1995 to 2000 and 2001 to 2006 (P < 0.02). However, when cases were normalized by all annual pediatric emergency department visits for all medical reasons, the increase was reduced to 22% and lost statistical significance (P = 0.16). The rise was not associated with a change in etiologies or body mass index (BMI).

Conclusions:

This is the first report demonstrating that an increase in pediatric pancreatitis may in part be due to growing referrals to tertiary care centers. The data on etiologies, particularly with regard to differing ages, may be helpful in managing children who present with acute pancreatitis.
Screening of Metabolic Syndrome in Obese Children: A Primary Care Concern
Authors: Viggiano Domenico , De Filippo Gianpaolo , Rendina Domenico , Fasolino Antonio , D'Alessio Norma , Avellino Natalia , Verga Maria Carmela , Prisco Antonio Giosué , Sorrentino Felice Antonio , Sabatini Paola , Chiarelli Francesco ,   O.Si.M.E. Study Group
Published: August 2009

Objective:

To determine the prevalence of metabolic syndrome (MS) in a primary care pediatric setting and to collect clinical and biochemical data, allowing for a prediction of its presence in a supposedly healthy population.

Methods:

Belonging to a pediatric population followed by pediatricians of the Italian National Health Service, 415 subjects with obesity as a unique selection criterion were enrolled. The entire cohort was screened for MS, which was defined as the presence of at least 2 other findings out of obesity: fasting hyperglycemia, low levels of high‐density lipoproteins cholesterol, hypertriglyceridemia, and hypertension.

Results:

The overall prevalence of MS was 30.8%. Major findings (out of obesity) were low high‐density lipoproteins cholesterol levels (46.2%), hypertension (23.6%), hypertriglyceridemia (22.2%), and fasting hyperglycemia (16.6%). Waist‐to‐height ratio was the only clinical parameter directly related to MS, with the same predictive power of insulin resistance.

Conclusions:

Metabolic syndrome can be present in a significant percentage of “healthy” obese children, and a simple clinical parameter could identify at‐risk subjects. This observation justifies the development and implementation of pediatric networks for obesity screening programs.
Hepatic Fibrosis Scan for Liver Stiffness Score Measurement: A Useful Preendoscopic Screening Test for the Detection of Varices in Postoperative Patients With Biliary Atresia
Authors: Chang Hye Kyung , Park Youn Joon , Koh Hong , Kim Seong Min , Chung Ki Sup , Oh Jung Tak , Han Seok Joo
Published: August 2009

Objective:

Even after successful Kasai portoenterostomy, progressive hepatic fibrosis in postoperative patients with biliary atresia (BA) can be associated with portal hypertension and esophageal or gastric varices. Therefore, early diagnosis and close follow‐up of varices are important. We investigated the correlation between the liver stiffness scores measured by FibroScan and the presence of esophageal or gastric varices to examine the usefulness of FibroScan as a preendoscopic screening test for varices.

Patients and Methods:

A total of 49 of 81 children with BA following successful Kasai operations were enrolled in this study. FibroScan and endoscopic examination were performed prospectively.

Results:

There were 22 males (44.9%) and the mean age of the patients was 3.8 ± 2.7 years. Esophageal or gastric varices were present in 30 patients (Vx group) and absent in 19 (nVx group). The mean liver stiffness score was significantly higher in the Vx group (21.35 ± 10.31 kPa in the Vx group versus 9.75 ± 8.61 kPa in the nVx group, P < 0.001). The optimal cutoff value of the liver stiffness score for the prediction of a varix was 9.7 kPa with a sensitivity of 0.97 and a specificity of 0.80.

Conclusions:

Liver stiffness scores measured by FibroScan correlate well with the presence of esophageal or gastric varices. FibroScan is a novel, noninvasive, and useful screening method for the preendoscopic detection of varices in postoperative patients with BA.
Impact of the black rhinoceros (Diceros bicornis minor) on a local population of Euphorbia bothae in the Great Fish River Reserve, South Africa
Authors: Luske Bodina L. , Mertens Tonja , Lent Peter C. , De Boer Willem F. , Prins Herbert H. T.
Published: August 2009

In the Great Fish River Reserve, South Africa, black rhinoceros (Diceros bicornis minor) feed extensively on a local population of Euphorbia bothae. Maintaining the endangered black rhinoceros and the protected E. bothae population are both conservation priorities of the reserve. Therefore, the sustainability of this plant–animal interaction was investigated by comparing population characteristics, browsing incidence and intensity within the reserve and in an adjacent exclosure without access to rhino. Fixed‐point photographs showed that over a 2‐month period 36.6% of 213 monitored plants were browsed, with an average biomass loss of 13%, and 1% were destroyed. Of 26 plants re‐photographed after approximately 3 years, 70% showed a decrease in biomass, averaging 37.8% over this period. In this time span, 19% of the monitored plants died. Small plants (<45 cm) were over‐represented in the rhino‐browsed area, whereas the fraction of reproductively active plants and overall plant density were found to be lower than in the adjacent exclosure. No evidence of short‐term compensatory growth in response to browsing was found for E. bothae. This study indicates that, with the current population size, rhinos are overexploiting the E. bothae population and special measures should be taken to prevent local extinction.
Hunting, disturbance and roost persistence of bats in caves at Ankarana, northern Madagascar
Authors: Cardiff Scott G. , Ratrimomanarivo Fanja H. , Rembert Guillaume , Goodman Steven M.
Published: August 2009

Surveys and monitoring of 37 caves in and around the Ankarana Special Reserve, northern Madagascar, yielded evidence of hunting of bats and potential disturbance of bats by miners and tourists, and colony counts for several bat species of potential conservation concern. Colony size decreased by 95% and 14% for a colony of Hipposideros commersoni and a colony of Eidolon dupreanum, respectively, when recent evidence of hunting occurred at those colonies and those declines are probably attributable to hunting. Evidence of hunting occurred commonly at the roosts of those species and most commonly at the roosts of Rousettus madagascariensis. Hunting of pteropodids was associated with high vulnerability of roosts to hunters, little forest buffer between the cave and open savannah and the absence of tombs in the cave. Roost sites of the hunted species persisted for at least several years and this regularity may facilitate hunting. This work supports the ranking of E. dupreanum, R. madagascariensis and H. commersoni as species of conservation concern. Managers should consider the impact of tourist visits on bats and of increasing access to caves for tourism. Conservation efforts for the hunted species should also seek to protect vulnerable and unprotected cave roosts.
Seasonality in adult flight activity of two neuroptera assemblages of southern Mali
Authors: Michel Bruno , Cadet Patrice
Published: August 2009

The seasonality of insect assemblages in Africa is poorly investigated. To provide information on the relationships between climate and insect assemblages in the Sudanian region, strongly affected by climate change, we studied Myrmeleontidae and Ascalaphidae assemblages (Insecta: Neuroptera) for 7 and 5 consecutive years respectively in southern Mali. To make the species inventory as exhaustive as possible, we performed weekly sampling by netting and light trapping. For both assemblages, results showed very similar patterns of variation in species diversity throughout the year. Adults of Myrmeleontidae and Ascalaphidae were active all year, and the species succession was influenced by a strong temporal segregation. Species diversity peaked at the end of the rainy season and surprisingly during the dry season. Principal component analysis of the climatic factors followed by co‐inertia analysis applied to two data sets, one comprising climatic factors and the other reporting presence/absence of species, showed a good association between the annual trend of climatic factors and the species diversity. But no well defined species grouping was clearly linked to a particular period of the year. This tight association between climate and species composition suggests that even small climate changes could modify significantly species assemblage characteristics.
Implications of closed ecosystem conservation management: the decline of Rothschild’s giraffe (Giraffa camelopardalis rothschildi) in Lake Nakuru National Park, Kenya
Authors: Brenneman Rick A. , Bagine Richard K. , Brown David M. , Ndetei Robert , Louis Edward E.
Published: August 2009

Giraffe were historically free‐ranging across most of sub‐Saharan Africa but are now most often confined to national parks, conservation areas, or private ranches. Five viable populations of Rothschild’s giraffe (Giraffa camelopardalis rothschildi) remain in protected areas in Kenya and Uganda. The viable population in Uganda is Murchison Falls National Park and the four populations in Kenya are Lake Nakuru National Park (LNNP), Ruma National Park, Giraffe Manor, and Mwea Natural Reserve. The Kenya Wildlife Service queried a rapid decline in LNNP giraffe numbers falling from 153 individuals (1995) to 62 individuals (2002) and the failure of that population to recruit young in those years. Significantly reduced browse options, inbreeding depression and preferential lion predation were considered as potential reasons for this trend. Population genetic parameter estimates derived from multilocus genotype analyses suggest that the LNNP population was in good genetic health with respect to the likelihood of inbreeding depression. The population decline coincided with the drought attributed to the 1994 El Niño. Possible dietary complications from highly concentrated tannin levels because of forced over consumption of the park’s declining acacia trees may have compromised young giraffe, making them easy and opportunistic prey for the park’s lion population.
Composition and distribution of vascular epiphytes in a tropical semideciduous forest, Ghana
Authors: Addo‐Fordjour Patrick , Anning Alexander Kofi , Addo Mathew Glover , Osei Margaret Frimpomaa
Published: August 2009

The composition and distribution of vascular epiphytes were studied in two 1‐ha plots in the KNUST Botanic garden, Ghana. One‐hectare plot each was randomly set up in secondary and cultivated forests for the identification and enumeration of trees and shrubs (≥10 cm dbh), and epiphytes. Each tree was carefully examined, noting the presence, positions and life‐forms of all epiphytes. Twenty‐nine epiphyte (29) species belonging to fourteen genera and eleven families were identified in the study. These were hosted by 48 tree species and occurred in three life‐forms: hemi‐epiphytes (45%), casual epiphytes (45%) and true epiphytes (10%). The vascular epiphyte species made up 25.7% of all the identified plant species (excluding herbs and climbers) encountered. Host species (P < 0.001), habitat (P = 0.001) and their interaction (P < 0.001) had strong effects on epiphyte composition in the forests. Moraceae was the most dominant family (44.8%), while Nephrolepis undulata J. Sm. and N. biserrata (Sw.) Scott. were the commonest species of epiphytes. In terms of vertical distribution, most epiphytes were located on the trunk, while a few occurred in the canopy.
Invertebrate community structure and ecosystem functioning in European conifer plantation streams
Authors: RIIPINEN MIIRA P. , FLEITUCH TADEUSZ , HLADYZ SALLY , WOODWARD GUY , GILLER PAUL , DOBSON MICHAEL
Published: August 2009

1. Terrestrial leaf‐litter is the dominant energy input to many headwater streams and consequently the nature of the riparian vegetation can have profound effects on in‐stream processes. The impact of conifer plantations on community structure and ecosystem functioning (litter breakdown) was investigated in field experiments in three countries (Britain, Ireland, Poland), each representing a distinct European ecoregion. Twenty‐six streams were used in the trial: half were bordered with broadleaved and the other half with conifer riparian vegetation.

2. In a leaf breakdown study using litter bags, two leaf types (oak and alder) were used to assess the impact of resource quality and two mesh sizes (10 and 0.5 mm aperture) were used to gauge the relative importance of invertebrate detritivores and microbial decomposers respectively. Comparisons were made between vegetation types and among regions; pH varied among individual streams but, unlike many previous studies, it was not confounded with vegetation type, enabling us to isolate the effect of vegetation more effectively.

3. Overall, riparian vegetation type did not affect breakdown rates but strong regional differences were observed. There was also a significant interaction between these two variables, but this disappeared after fitting pH as a covariable, demonstrating its importance in determining breakdown rates and raising the possibility that in previous studies the impacts of conifer plantations might have been confounded with pH.

4. Shredder species composition differed between vegetation types. Small stoneflies were most strongly associated with conifer streams; broadleaved streams generally had a higher proportion of larger taxa, such as limnephilid caddisflies and gammarid shrimps, although the latter were excluded from sites with low pH. However, breakdown rates were maintained irrespective of shredder community composition, suggesting a high degree of functional redundancy in these communities. Similar processing rates were observed between streams with high numbers of nemourids and those with only a few limnephilids or gammarids, suggesting that density compensation among consumers might stabilise process rates.

5. Our results suggest that leaf‐litter breakdown can be an effective proxy for assessing stream ecosystem functioning, as rates differed significantly across spatial scales, from between streams to across regions and responded to an environmental gradient (pH). The litter bag technique can also complement traditional assessment methods by providing valuable information on the composition of consumer guilds, thereby providing an important link between structure and function that is needed to help inform management practices.
‘Value of FSH and inhibin‐B measurements in the diagnosis of azoospermia’– A clinician’s overview
Authors: Adamopoulos D. A. , Koukkou E. G.
Published: August 2009

Azoospermia can be either of obstructive ctiology or due to the testis' failure to initiate or maintain spermatogenesis. FSH acts through its receptor at Sertoli cell level and modulates spermatogenesis initiation and maintenance. Inhibin B is a Sertoli cell product expressing the functional capacity of the cell and in an indirect way the state of seminiferous tubule activity. Both FSH and inhibin B differentiate clearly testicular from extra‐testicular pathology of azoospermia while, none of these hormones has been convincingly established as predictory index for the finding of spermatozoa in TESE.
Biogeographical patterns of blood parasite lineage diversity in avian hosts from southern Melanesian islands
Authors: Ishtiaq Farah , Clegg Sonya M. , Phillimore Albert B. , Black Richard A. , Owens Ian P. F. , Sheldon Ben C.
Published: August 2009

Aim  (1) To describe the species–area relationships among communities of Plasmodium and Haemoproteus parasites in different island populations of the same host genus (Aves: Zosterops). (2) To compare distance–decay relationships (turnover) between parasite communities and those with potential avian and dipteran hosts, which differ with respect to their movement and potential to disperse parasite species over large distances.

Location  Two archipelagos in the south‐west Pacific, Vanuatu and New Caledonia (c. 250 km west of Vanuatu) and its Loyalty Islands, with samples collected from a total of 16 islands of varying sizes (328–16,648 km2).

Methods  We characterized parasite diversity and distribution via polymerase chain reaction (PCR) from avian (Zosterops) blood samples. Bayesian methods were used to reconstruct the parasite phylogeny. In accordance with recent molecular evidence, we treat distinct mitochondrial DNA lineages as equivalent to species in this study. Path analysis and parasite lineage accumulation curves were used to assess the confounding effect of inadequate sampling on the estimation of parasite richness. Species–area and species–distance relationships were assessed using linear regression: distance–decay relationships were assessed using Mantel tests.

Results  Birds and mosquito species and Plasmodium lineages exhibited significant species–area relationships. However, Plasmodium lineages showed the weakest ‘species–area’ relationship; no relationship was found for Haemoproteus lineages. Avian species richness influenced parasite lineage richness more than mosquito species richness did. Within individual avian host species, the species–area relationship of parasites showed differing patterns. Path analysis indicated that sampling effort was unlikely to have a confounding effect on parasite richness. Distance from mainland (isolation effect) showed no effect on parasite richness. Community similarity decayed significantly with distance for avifauna, mosquito fauna and Plasmodium lineages but not for Haemoproteus lineages.

Main conclusions  Plasmodium lineages and mosquito species fit the power‐law model with steeper slopes than found for the avian hosts. The lack of species–distance relationship in parasites suggests that other factors, such as the competence of specific vectors and habitat features, may be more important than distance. The decay in similarity with distance suggests that the sampled Plasmodium lineages and their potential hosts were not randomly distributed, but rather exhibited spatially predictable patterns. We discuss these results in the context of the effects that parasite generality may have on distribution patterns.
Ant communities on small tropical islands: effects of island size and isolation are obscured by habitat disturbance and ‘tramp’ ant species
Authors: Rizali Akhmad , Lohman David J. , Buchori Damayanti , Prasetyo Lilik Budi , Triwidodo Hermanu , Bos Merijn M. , Yamane Seiki , Schulze Christian H.
Published: August 2009

Aim  Comparisons among islands offer an opportunity to study the effects of biotic and abiotic factors on small, replicated biological communities. Smaller population sizes on islands accelerate some ecological processes, which may decrease the time needed for perturbations to affect community composition. We surveyed ants on 18 small tropical islands to determine the effects of island size, isolation from the mainland, and habitat disturbance on ant community composition.

Location  Thousand Islands Archipelago (Indonesian name: Kepulauan Seribu) off Jakarta, West Java, Indonesia.

Methods  Ants were sampled from the soil surface, leaf litter and vegetation in all habitat types on each island. Island size, isolation from the mainland, and land‐use patterns were quantified using GIS software. The presence of settlements and of boat docks were used as indicators of anthropogenic disturbance. The richness of ant communities and non‐tramp ant species on each island were analysed in relation to the islands’ physical characteristics and indicators of human disturbance.

Results  Forty‐eight ant species from 5 subfamilies and 28 genera were recorded from the archipelago, and approximately 20% of the ant species were well‐known human‐commensal ‘tramp’ species. Islands with boat docks or human settlements had significantly more tramp species than did islands lacking these indicators of anthropogenic disturbance, and the diversity of non‐tramp species decreased with habitat disturbance.

Main conclusions  Human disturbance on islands in the Thousand Islands Archipelago promotes the introduction and/or establishment of tramp species. Tramp species affect the composition of insular ant communities, and expected biogeographical patterns of ant richness are masked. The island with the greatest estimated species richness and the greatest number of unique ant species, Rambut Island, is a forested bird sanctuary, highlighting the importance of protected areas in preserving the diversity of species‐rich invertebrate faunas.
QseC‐mediated dephosphorylation of QseB is required for expression of genes associated with virulence in uropathogenic Escherichia coli
Authors: Kostakioti Maria , Hadjifrangiskou Maria , Pinkner Jerome S. , Hultgren Scott J.
Published: August 2009

Bacteria sense environmental cues and regulate gene expression accordingly so as to persist in diverse niches. QseC is a membrane sensor kinase shown in enterohemorrhagic Escherichia coli to respond to host and bacterial signals by phosphorylating the QseB response regulator at residue D51, resulting in QseB activation and presumably upregulation of virulence genes. We studied QseBC in uropathogenic E. coli (UPEC). UPEC establish infection by colonizing and invading bladder cells. After invasion, UPEC can escape into the cytoplasm where they can form intracellular bacterial communities. Deletion of qseC significantly attenuated intracellular bacterial community formation and virulence, whereas paradoxically qseB deletion did not impact pathogenesis. We found that QseB upregulates its own expression in the qseC mutant, arguing that it is activated even in the absence of QseC. However, expression of QseB, but not a QseB_D51A mutant, in the absence of QseC resulted in downregulation of type 1 pili, curli and flagella. We observed similar phenotypes with enterohemorrhagic E. coli, showing that this is not a UPEC‐specific phenomenon. Target gene expression is restored when QseC is present. We discovered that QseC has phosphatase activity required for QseB dephosphorylation. Thus, the QseC phosphatase capacity is critical for modulating QseB activity and subsequent gene expression.
(2S)‐Methylsuccinyl‐CoA dehydrogenase closes the ethylmalonyl‐CoA pathway for acetyl‐CoA assimilation
Authors: Erb Tobias J. , Fuchs Georg , Alber Birgit E.
Published: August 2009

Many organic substrates are metabolized via acetyl‐coenzyme A (CoA) and enter central carbon metabolism at the level of this compound. We recently described the outlines of the ethylmalonyl‐CoA pathway, a new acetyl‐CoA assimilation strategy that operates in a number of bacteria such as Rhodobacter sphaeroides, Methylobacterium extorquens and streptomycetes and replaces the glyoxylate cycle. This new pathway involves a unique central reaction sequence catalysed by characteristic enzymes. Here, we identified and characterized (2S)‐methylsuccinyl‐CoA dehydrogenase from R. sphaeroides, a flavin adenine dinucleotide‐containing enzyme that catalyses the last unknown step in the central part of the ethylmalonyl‐CoA pathway, the oxidation of (2S)‐methylsuccinyl‐CoA to mesaconyl‐(C1)‐CoA. This enzyme is highly specific for its substrate and forms a distinct subgroup within the superfamily of flavin‐dependent acyl‐CoA dehydrogenases. Homology modelling and comparative sequence analyses with well‐studied members of this superfamily identified amino acids that may contribute to the narrow substrate specificity of (2S)‐methylsuccinyl‐CoA dehydrogenase. The central part of the ethylmalonyl‐CoA pathway was reconstituted in vitro using four recombinant enzymes. By this work, the ethylmalonyl‐CoA pathway and its stereochemical course have been completely solved. This allowed defining the minimum set of enzymes necessary for its operation and to screen for further organisms following this acetyl‐CoA assimilation strategy.
Rcs signalling‐activated transcription of rcsA induces strong anti‐sense transcription of upstream fliPQR flagellar genes from a weak intergenic promoter: regulatory roles for the anti‐sense transcript in virulence and motility
Authors: Wang Qingfeng , Harshey Rasika M.
Published: August 2009

In Salmonella enterica, an activated Rcs signalling system inhibits initiation of transcription of the flhD master operon. Under these conditions, where motility is shut down, microarray experiments showed an increased RNA signal for three flagellar genes –fliPQR– located upstream of rcsA. We show here that it is the anti‐sense (AS) strand of these genes that is transcribed, originating at a weak promoter in the intergenic region between fliR and rcsA. RcsA is an auxiliary regulator for the Rcs system, whose transcription is dependent on the response regulator RcsB. Rcs‐activated rightward transcription, but not translation, of rcsA is required for stimulation of leftward AS transcription. Our results implicate a combined action of RcsB and rcsA transcription in activating the AS promoter, likely by modulating DNA superhelicity in the intergenic region. We show that the AS transcript regulates many genes in the Rcs regulon, including SPI‐1 and SPI‐2 virulence and stress‐response genes. In the wild‐type strain the AS transcript is present in low amounts, independent of Rcs signalling. Here, AS transcription modulates complementary sense RNA levels and impacts swarming motility. It appears that the flagellar AS transcript has been co‐opted by the Rcs system to regulate virulence.
Borrelia burgdorferi small lipoprotein Lp6.6 is a member of multiple protein complexes in the outer membrane and facilitates pathogen transmission from ticks to mice
Authors: Promnares Kamoltip , Kumar Manish , Shroder Deborah Y. , Zhang Xinyue , Anderson John F. , Pal Utpal
Published: August 2009

Borrelia burgdorferi lipoprotein Lp6.6 is a differentially produced spirochete antigen. An assessment of lp6.6 expression covering representative stages of the infectious cycle of spirochetes demonstrates that the gene is solely expressed during pathogen persistence in ticks. Deletion of lp6.6 in infectious B. burgdorferi did not influence in vitro growth, or its ability to persist and induce inflammation in mice, migrate to larval or nymphal ticks or survive through the larval‐nymphal molt. However, Lp6.6‐deficient spirochetes displayed significant impairment in their ability to transmit from infected ticks to naïve mice, which was restored upon genetic complementation of the mutant with a wild‐type copy of lp6.6, establishing that Lp6.6 plays a role in pathogen transmission from ticks to mammals. Lp6.6 is a subsurface, yet highly abundant, outer membrane antigen. Two‐dimensional blue native/SDS‐PAGE coupled with liquid chromatography‐mass spectrometry (LC‐MS/MS) analysis and protein cross‐linking studies independently shows that Lp6.6 exists in multiple protein complexes in the outer membrane. We speculate that the function of Lp6.6 is connected to the physiological processes of these membrane complexes. Further characterization of differentially produced membrane antigens and associated protein complexes will likely aid in our understanding of the molecular details of B. burgdorferi persistence and transmission through a complex enzootic cycle.
Role of DegP for two‐partner secretion in Bordetella
Authors: Baud C. , Hodak H. , Willery E. , Drobecq H. , Locht C. , Jamin M. , Jacob‐Dubuisson F.
Published: August 2009

Sorting of proteins destined to the surface or the extracellular milieu is mediated by specific machineries, which guide the protein substrates towards the proper route of secretion and determine the compartment in which folding occurs. In Gram‐negative bacteria, the two‐partner secretion (TPS) pathway is dedicated to the secretion of large proteins rich in β‐helical structure. The secretion of the filamentous haemagglutinin (FHA), a 230 kDa adhesin of Bordetella pertussis, represents a model TPS system. FHA is exported by the Sec machinery and transits through the periplasm in an extended conformation. From there it is translocated across the outer membrane by its dedicated transporter FhaC to finally fold into a long β‐helix at the cell surface in a progressive manner. In this work, we show that B. pertussis lacking the periplasmic chaperone/protease DegP has a strong growth defect at 37°C, and the integrity of its outer membrane is compromised. While both phenotypes are significantly aggravated by the presence of FHA, the chaperone activity of DegP markedly alleviates the periplasmic stress. In vitro, DegP binds to non‐native FHA with high affinity. We propose that DegP chaperones the extended FHA polypeptide in the periplasm and is thus involved in the TPS pathway.
Efficacy and cost‐effectiveness of cell saving blood autotransfusion in adult lumbar fusion
Authors: Savvidou C. , Chatziioannou S. N. , Pilichou A. , Pneumaticos S. G.
Published: August 2009

summary.

The objective of this study was to explore the use of cell saver blood autotransfusion in spinal surgery and to evaluate the efficacy and cost‐effectiveness of cell saver blood autotransfusion during lumbar spine fusion in adults. Specific indications for the use of cell saver in adult lumbar fusion surgery have not yet been clearly determined. A total of 50 consecutive candidates for posterolateral fusion with internal fixation were prospectively randomized into either receiving perioperatively cell saving autotransfusion (Group A: 25 patients) or not (Group B: 25 patients). The use of cell saving technique did not exclude the use of allogenic blood transfusion. Surgical indications were spinal stenosis, spondylolisthesis, adolescent idiopathic scoliosis, degenerative scoliosis and fractures. Medical and financial data were recorded. A cost‐analysis was performed. Patients in Group A received 880 ± 216 mL from cell saver and 175 ± 202 mL allogenic blood. The patients in Group B received 908 ± 244 mL allogenic blood. Blood volumes data collected were expressed in mean ± SD values. The cost of blood transfusion in Group A was 995 ±€447 per patient and 1220 ± 269 in Group B (P < 0.05). In elective lumbar fusion blood requirements can be satisfied with the use of autotransfusion. The use of cell saver appears to be useful and cost‐effective during most elective lumbar fusions.
Effectiveness of nanofiltration in removing small non‐enveloped viruses from three different plasma‐derived products
Authors: Menconi M. C. , Maggi F. , Zakrzewska K. , Salotti V. , Giovacchini P. , Farina C. , Andreoli E. , Corcioli F. , Bendinelli M. , Azzi A.
Published: August 2009

summary.

The objective of this study was to assess the ability of nanofiltration of albumin solution, prothrombin complex (PTC) and factor IX (FIX) to remove two small, non‐enveloped DNA viruses, parvovirus B19 (B19V) and torque teno virus (TTV). Virus removal was investigated with down‐scale experiments performed with sequential steps of 35‐nm and 15‐nm nanofiltrations of products spiked with virus DNA‐positive sera. Viral loads were determined by real‐time PCRs. The 15‐nm nanofiltration removed more than 4.0 B19V log from all the products, TTV was reduced of more than 3.0 log from albumin solution and FIX by 35‐nm and 15‐nm nanofiltrations, respectively, being viral DNA undetectable after these treatments. Traces of TTV were still found in PTC after the 15‐nm nanofiltration. In conclusion, nanofiltration can be efficacious in removing small naked viruses but, since viruses with similar features can differently respond to the treatment, a careful monitoring of large‐scale nanofiltration should be performed.