bluuebunny/crossref_metadata_2025_split huggingface dataset:
Chaperonin-mediated protein folding: fate of substrate polypeptide
Authors: Fenton Wayne A. , Horwich Arthur L. 
Published: October 2003

1. Chaperonin action – an overview 2302. Polypeptide binding – an essential action 2353. Recognition of non-native polypeptide – role of hydrophobicity 2364. Crystallographic analyses of peptide binding 2375. Topology and secondary and tertiary structure of bound substrate polypeptide – fluorescence, hydrogen exchange and NMR studies 2396. Binding by GroEL associated with a putative unfolding action 2427. A potential action of substrate unfolding driven by ATP/GroES binding 2458. Folding in theciscavity 2479. GroEL–GroES-mediated folding of larger substrate proteins by atransmechanism 24910. Prospects for resolving the conformations and fate of polypeptide in the chaperonin reaction 25111. References 252Chaperonins are megadalton ring assemblies that mediate essential ATP-dependent assistance of protein folding to the native state in a variety of cellular compartments, including the mitochondrial matrix, the eukaryotic cytosol, and the bacterial cytoplasm. Structural studies of the bacterial chaperonin, GroEL, both alone and in complex with its co-chaperonin, GroES, have resolved the states of chaperonin that bind and fold non-native polypeptides. Functional studies have resolved the action of ATP binding and hydrolysis in driving the GroEL–GroES machine through its folding-active and binding-active states, respectively. Yet the exact fate of substrate polypeptide during these steps is only poorly understood. For example, while binding involves multivalent interactions between hydrophobic side-chains facing the central cavity of GroEL and exposed hydrophobic surfaces of the non-native protein, the structure of any polypeptide substrate while bound to GroEL remains unknown. It is also unclear whether binding to an open GroEL ring is accompanied by structural changes in the non-native substrate, in particular whether there is an unfolding action. As a polypeptide-bound ring becomes associated with GroES, do the large rigid-body movements of the GroEL apical domains serve as another source of a potential unfolding action? Regarding the encapsulated folding-active state, how does the central cavity itself influence the folding trajectory of a substrate? Finally, how do GroEL and GroES serve, as recently recognized, to assist the folding of substrates too large to be encapsulated inside the machine? Here, such questions are addressed with the findings available to date, and means of further resolving the states of chaperonin-associated polypeptide are discussed.
A dialogue with Gordon McConville on Deuteronomy
Authors: Clements Ronald E. , Moberley R. W. L. , McConville G. J. 
Published: October 2003

I. The origins of Deuteronomy: what are the clues?II. Theological interpretation of an OT book: a response to Gordon McConville's DeuteronomyIII. A response from Gordon McConville
Predation on foam nests of leptodactyline frogs (Anura: Leptodactylidae) by larvae of Beckeriella niger (Diptera: Ephydridae)
Authors: Menin Marcelo , Giaretta Ariovaldo A. 
Published: October 2003

AbstractThe presence of maggots of the fly Beckeriellaniger (Ephydridae) in nests of six syntopic South American leptodactyline frogs is reported. The number of tadpoles of Physalaemus cuvieri leaving infested and non‐infested nests were compared, and behavioural plasticity at the time of nest departure in the presence and absence of maggots was tested for. Maggots were found in nests of all species with exposed foam nests (four Physalaemus and two Leptodactylus species). The maggots remained in the nests of P. cuvieri for up to 3 days; adults emerged from pupae after 7 days. While in the nests the maggots consumed eggs, embryos, and tadpoles. The levels of infestation increased from the beginning to the middle of the rainy season. Mortality caused by the maggots represented an important source of mortality (mean 74%) of eggs and embryos of P. cuvieri, and probably, of the other species. The time of emergence from nests by the tadpoles of P. cuvieri was shorter (up to 21 h earlier) in infested nests. The tadpoles that left the infested nests were at the same, or a less‐developed stage than tadpoles in non‐infested nests. The variation in the degree of infestation, with lower values at the beginning and the increase to the middle of the rainy season, suggests that the flies may be an obligatory predator on foam nests. For tadpoles of P. cuvieri, entering the water at a later developmental stage may be important to avoid aquatic predators. Conversely, leaving infested nests at the earliest possible stage may represent a strategy to avoid maggot predation. The longer time before emergence of tadpoles of P. cuvieri from non‐infested nests corroborates the hypothesis that, among leptodactyline frogs, the foam nest is a predator avoidance adaptation in the aquatic media.
Of “crashes” and “accidents,” a comment on Stewart and Lord
Authors: Blanchard Edward B. , Hickling Edward J. , Kuhn Eric 
Published: October 2003

AbstractA. E. Stewart and J. H. Lord (2002) call for abandoning the term motor vehicle accident and substituting motor vehicle crash on definitional and patient care grounds. We disagree on definitional grounds and because of the absence of empirical data from accident survivors to support their contentions.
Spirituality, resilience, and anger in survivors of violent trauma: A community survey
Authors: Connor Kathryn M. , Davidson Jonathan R. T. , Lee Li‐Ching 
Published: October 2003

AbstractThis study evaluates the relationship between spirituality, resilience, anger and health status, and posttraumatic symptom severity in trauma survivors. A community sample (N = 1,200) completed an online survey that included measures of resilience, spirituality (general beliefs and reincarnation), anger, forgiveness, and hatred. In survivors of violent trauma (n = 648), these measures were evaluated with respect to their relationship to physical and mental health, trauma‐related distress, and posttraumatic symptom severity. Using multivariate regression models, general spiritual beliefs and anger emerged in association with each outcome, whereas resilience was associated with health status and posttraumatic symptom severity only. Forgiveness, hatred, and beliefs in reincarnation were not associated with outcome. The importance of these findings to treating trauma survivors is discussed.
Symptom exaggeration and compensation seeking among combat veterans with posttraumatic stress disorder
Authors: DeViva Jason C. , Bloem William D. 
Published: October 2003

AbstractCombat veterans seeking treatment for posttraumatic stress disorder (PTSD) tend to report high levels of psychopathology on self‐report instruments. The purpose of the current archival study was to replicate research on the relationships among symptom exaggeration, attempts to obtain compensation, and treatment outcome on the Beck Depression Inventory, the Mississippi Scale for Combat‐Related PTSD, and selected MMPI‐2 and MCMI‐II subscales. Results indicated that symptom exaggeration as defined by an MMPI‐2 F‐K index over 13 was related to higher scores on all scales examined. Compensation seeking was not related to assessment scores or exaggeration. Neither compensation seeking nor exaggeration was related to treatment outcome. Limitations of the study and implications for future research are discussed.
Longitudinal evaluation of GCF IFN‐γ levels and periodontal status in HIV+ patients
Authors: Alpagot T. , Font K. , Lee A. 
Published: October 2003

AbstractBackground/Aim: Loss of periodontal support and related tooth loss is a common finding among HIV+ patients. The etiology of this destruction may be an increase in the levels of pro‐inflammatory cytokines and subsequent increase in periodontal disease activity. The purpose of this study was to investigate the associations between gingival crevicular fluid interferon gamma (GCF IFN‐γ) and clinical measures of periodontal disease in HIV+ individuals. We monitored GCF IFN‐γ and periodontal status of selected sites in 33 HIV+ subjects over a 6‐month period.Method: Clinical measurements including gingival index, plaque index, bleeding on probing, probing depth, attachment loss (AL), and GCF samples were taken from four lower incisors and the upper right posterior sextant of each patient at baseline and 6‐month visits by means of sterile paper strips. GCF levels of IFN‐γ were determined by sandwich ELISA assays. A progressing site was defined as a site that had 2 mm or more AL during the 6‐month study period.Results: Twenty‐five of the 264 examination sites showed 2 mm or more clinical AL during the 6‐month study period. Significantly higher GCF levels of IFN‐γ were found at progressing sites than in nonprogressing sites (p<0.001). GCF levels of IFN‐γ were highly correlated with clinical measurements taken at baseline and 6‐month visits (0.001<p<0.01).Conclusion: These data indicate that sites with high GCF levels of IFN‐γ are at significantly greater risk for progression of periodontitis in HIV+ patients.
Self‐reported gingival conditions and self‐care in the oral health of Danish women during pregnancy
Authors: Christensen Lisa Bøge , Jeppe‐Jensen Dorte , Petersen Poul Erik 
Published: October 2003

AbstractObjectives: The purpose of the present study was to describe the self‐assessment of gingival health conditions in pregnant women, their oral hygiene behaviour and dental visiting habits, and to analyse self‐care practices of pregnant women in relation to perceived gingival problems.Material and Methods: The study group comprised 1935 pregnant women living in two areas of Denmark consecutively recruited from August 1998 to March 1999. The survey data were based on telephone interviews. Questions in the interview concerned general health, lifestyles, socioeconomic conditions, gingival conditions, oral hygiene and utilisation of dental health services.Results: One‐third of the study population perceived signs of gingival inflammation; 5% of the pregnant women assessed their gingiva as poor, while 95% reported good or “normal” gingival condition. Ninety six per cent brushed their teeth at least twice a day and nine out of 10 were regular users of the dental‐care system. Twenty‐seven per cent of those women with pregnancy gingivitis responded to the symptoms by, for example, seeing a dentist or intensifying the oral hygiene habits.Conclusion: Despite a high level of self‐efficacy among the pregnant women as for oral health and oral health care combined with a high level of oral hygiene and dental visiting habits, there seems to be a substantial need for increased awareness of gingival oral health.
Skin biophysical properties of a population living in Valais, Switzerland
Authors: Wendling Pierre‐André , Dell'Acqua Giorgio 
Published: October 2003

Background/purpose: Switzerland has one of the highest rates of skin diseases and particularly skin cancer, in Europe. Skin elastosis, roughness and atopy are also frequent. High UV exposure and prevalence of light skin individuals could be the cause. Valais, in Southern Switzerland, is a mountain region with elevated sun irradiation and low air humidity, an ideal location to study the effect of the environment and life style on skin biophysical characteristics. The purpose of the study was to measure skin biophysical parameters non‐invasively on healthy subjects living in Valais, and to correlate the measures with their life style.Methods: One hundred and ten women were examined between October 2001 and February 2002. Measures of skin hydration, sebum content, pH and visco‐elasticity were taken in a closed environment with constant temperature and controlled air humidity, utilizing commercially available non‐invasive devices. Subjects were interviewed using a questionnaire and data on personal traits and life style were collected. Correlations between subject's skin parameters and life style were statistically examined.Results: On average we observed low values of skin capacitance that identify subjects with dry skin. Measures of skin visco‐elasticity ratios were also particularly low, while skin pH and sebum content were in the normal range. Age was correlated with a decrease of skin elasticity and sebum content, but there was no correlation with hydration or pH.Conclusions: We confirm, as reported in other studies, the effect of age on skin elasticity and sebum content and we identify, for the first time, a region with a population characterized by particularly low levels of skin hydration and skin visco‐elasticity. Although people examined were free of skin diseases, we believe that protection from the sun and treatment of skin with hydrating products need to be emphasized as a prevention strategy, in regions such as Valais, with high sun irradiation and low humidity.
Basal electrical impedance in relation to sodium lauryl sulphate‐induced skin reactions – a comparison of patients with eczema and healthy controls
Authors: Kuzmina Natalia , Hagströmer Lena , Nyrén Miruna , Emtestam Lennart 
Published: October 2003

Background: Identification of subjects at risk for contact dermatitis by screening tests is desirable in order to adjust the preventive measures to individual skin susceptibility. The present study aimed to examine the effects of basic physiological features, such as baseline electrical imped‐ance (IMP) and transepidermal water loss (TEWL), on reactivity to sodium lauryl sulphate (SLS).Methods: On the basis of two previous studies, we re‐evaluated the experimental irritant skin reactions (50 μL of 2% SLS in large Finn Chambers for 24 h) on the volar forearms of 29 patients with eczema and 19 healthy controls.Results: We found definite differences in the baseline values of IMP, between the patients and the controls. Moreover, patients with eczema showed higher TEWL and lower MIX values on day 3 after exposure to SLS, which may indicate differences in SLS reactivity. After the study, the biophysical parameters of the eczema patients did not return to baseline, which suggests that their skin heals more slowly than that of normal subjects.Conclusions: Our findings indicate that the IMP technique may help to ‘detect’ chemically vulnerable skin. However, more studies are needed to determine the value of the basal electrical impedance parameters in assessing the risk of developing irritant contact dermatitis.
Isolation of genes expressed during compatible interactions between leaf rust (Puccinia triticina) and wheat using cDNA‐AFLP
Authors: Zhang Lin , Meakin Helen , Dickinson Matt 
Published: October 2003

SUMMARYThe rust fungi are obligate biotrophic pathogens that depend on living host tissue for their growth. In compatible interactions they go through a number of developmental stages to form intercellular hyphae and haustoria within host cells, through which they obtain their nutrients. Here we have exploited the cDNA‐AFLP technique to isolate fragments of wheat and rust genes that are expressed at specific defined time‐points during the infection process. A number of these sequences were used as probes in Northern hybridizations and in RT‐PCR to confirm their expression patterns, and were also characterized by PCR analysis and Southern hybridizations to determine whether they are of fungal or wheat origin. A cDNA library was constructed from pooled RNAs extracted from days 5 and 7 after inoculation, and this library was screened to isolate full‐length cDNAs of selected sequences. Sequence analysis of these cDNA fragments and clones revealed similarities amongst the fungal genes to a chitinase, a sorbitol utilization protein, an arabinitol dehydrogenase and a proteasome regulatory unit, whilst in wheat, we identified sequences with homology to a katanin and a cell enlargement protein.
The influence of dissolved nutrients and particulate organic matter quality on microbial respiration and biomass in a forest stream
Authors: Stelzer Robert S. , Heffernan James , Likens Gene E. 
Published: October 2003

Summary1. Although dissolved nutrients and the quality of particulate organic matter (POM) influence microbial processes in aquatic systems, these factors have rarely been considered simultaneously. We manipulated dissolved nutrient concentrations and POM type in three contiguous reaches (reference, nitrogen, nitrogen + phosphorus) of a low nutrient, third‐order stream at Hubbard Brook Experimental Forest (U.S.A). In each reach we placed species of leaves (mean C : N of 68 and C : P of 2284) and wood (mean C : N of 721 and C : P of 60 654) that differed in elemental composition. We measured the respiration and biomass of microbes associated with this POM before and after nutrient addition.2. Before nutrient addition, microbial respiration rates and biomass were higher for leaves than for wood. Respiration rates of microbes associated with wood showed a larger response to increased dissolved nutrient concentrations than respiration rates of microbes associated with leaves, suggesting that the response of microbes to increased dissolved nutrients was influenced by the quality of their substrate.3. Overall, dissolved nutrients had strong positive effects on microbial respiration and fungal, but not bacterial, biomass, indicating that microbial respiration and fungi were nutrient limited. The concentration of nitrate in the enriched reaches was within the range of natural variation in forest streams, suggesting that natural variation in nitrate among forest streams influences carbon mineralisation and fungal biomass.
Laboratory experiments on the impact of biofilms on the plankton of a large river
Authors: Weitere Markus , Schmidt‐Denter Kerstin , Arndt Hartmut 
Published: October 2003

Summary1. Benthic organisms can have a strong effect on the plankton in rivers, although normally only members of the macrofauna are considered as important consumers. In the present study we conducted experiments on four different dates (in December, March, June and September) to assess the potential role of periphytic heterotrophic flagellates (HF), ciliates and rotifers in the control of potamoplankton (bacteria, algae, HF and ciliates).2. Natural periphyton was established on the walls of circular flow channels by exposing them to river water (River Rhine, Germany). The experimental channels (with periphyton) and control channels (without periphyton) were filled with riverine water and the increase rates of planktonic bacteria, algae, HF and oligotrich ciliates were determined for the two treatments.3. The abundance of periphytic ciliates and rotifers at the beginning of the four experiments showed large differences with low values in December and March, and high values in June and September. Dominant potential consumers of plankton were the heterotrich ciliate Stentor sp. and bdelloid rotifers.4. The rates of increase of planktonic algae, HF and ciliates were significantly smaller in the presence of periphyton compared with those in their absence. Significant interactions between the treatment (with and without periphyton) and the time of experiment were found for the planktonic HF and algae, indicating that the impact of the periphyton varied temporarily. The planktonic groups responded differently to the periphyton with the planktonic HF showing the highest loss rate. Significant differences were also found among the loss rates of different HF groups and different diatom size classes.5. These laboratory experiments demonstrate that periphytic ciliates and rotifers are potentially important consumers of different planktonic groups. The quantitative impact of periphyton on plankton with respect to the selective feeding needs further attention.
Diversity of bacteriorhodopsins in different hypersaline waters from a single Spanish saltern
Authors: Papke R. Thane , Douady Christophe J. , Doolittle W. Ford , Rodríguez‐Valera Francísco 
Published: October 2003

SummaryHaloarchaeal rhodopsins are a diverse group of transmembrane proteins that use light energy to drive several different cellular processes. Two rhodopsins, bacteriorhodopsin and halorhodopsins, are H+ and Cl– ion pumps, respectively, and two rhodopsins, sensory rhodopsin I and II, regulate phototaxis. Bacteriorhodopsin is of special interest as it is a non‐chlorophyll‐based type of phototrophy (i.e. generation of chemical energy from light energy). However, very little is known about the diversity and distribution of rhodopsin genes in hypersaline environments. Here, we have used environmental PCR and cloning techniques to directly retrieve rhodopsin genes from three different salinity ponds located in a sea salt manufacturing facility near Alicante, Spain. Our survey resulted in the discovery of previously concealed variation including what is hypothesized to be bacteriorhodopsin genes from the uncultivated square morphotype that dominates these environments. In some instances, identical genes were discovered in seemingly different habitats suggesting that some haloarchaea are present over widely varying concentrations of salt.
Erythema multiforme ID reaction in atypical dermatophytosis: a case report
Authors: Atzori L , Pau M , Aste M 
Published: October 2003

ABSTRACTBackground  Erythema multiforme (EM) is an uncommon mucocutaneous disorder, characterized by widespread erythematous‐oedematous targetoid lesions, considered as a reaction pattern to many different stimuli.Observation  Presentation is made of a classical EM eruption concomitant to an inflammatory, atypical dermatophytosis of the ala nasi, observed in a 37‐year‐old male at the Dermatology Department of Cagliari, Italy.Methods  Laboratory investigations revealed normal complete blood count and biochemistry profile. A direct microscopic examination with 20% potassium hydroxide of the nasal skin scales and of the vibrissae indicated the presence of dermatophyte hyphae and spores invading the rhinothrix. Culture confirmed a Trycophyton mentagrophytes infection. Specific determination of antiviral immunity in the blood (TORCH) was negative for recent infections, while the cell‐mediated response, investigated with a delayed skin multitest, showed a marked positivity for the tricophyton antigen. Systemic therapy with terbinafine (250 mg/day) led to complete clinical and mycological recovery of the atypical ringworm in 30 days. Multiforme lesions rapidly improved and completely disappeared in 7 days.Conclusions  ID reaction to a distant focus of dermatophyte infection very rarely presents as EM. The presented case fits all the essential criteria required for the diagnosis of an ID reaction. The atypical clinical presentation of the ringworm infection, with marked involvement of the intranasal hairs, seems to have induced an inflammatory allergic response, similar to that evoked by sycosis.