bluuebunny/crossref_metadata_2025_split huggingface dataset:
Bacterial contamination of platelet concentrates: results of a prospective multicenter study comparing pooled whole blood–derived platelets and apheresis platelets
Authors: Schrezenmeier Hubert , Walther‐Wenke Gabriele , Müller Thomas H. , Weinauer Franz , Younis Adelheid , Holland‐Letz Tim , Geis Gabriele , Asmus Jens , Bauerfeind Ursula , Burkhart Jürgen , Deitenbeck Robert , Förstemann Elisabeth , Gebauer Wolfgang , Höchsmann Britta , Karakassopoulos Apostolos , Liebscher Ute‐Maja , Sänger Werner , Schmidt Michael , Schunter Friedrich , Sireis Walid , Seifried Erhard 
Published: February 2007

BACKGROUND: The GERMS Group initiated a prospective multicenter study to assess prevalence and nature of bacterial contamination of pooled buffy‐coat platelet concentrates (PPCs) and apheresis platelet concentrates (APCs) by routine screening with a bacterial culture system.STUDY DESIGN AND METHODS: In nine centers overall, 52,243 platelet (PLT) concentrates (15,198 APCs, 37,045 PPCs) were analyzed by aerobic and anaerobic cultures (BacT/ALERT, bioMérieux).RESULTS: In 135 PLT concentrates (PCs; 0.26%), bacteria could be identified in the first culture (0.4% for APCs vs. 0.2% for PPCs; p < 0.001). In 37 (0.07%) of these PC units, the same bacteria strain could be identified in a second culture from the sample bag and/or the PC unit. The rate of confirmed‐positive units did not differ significantly between APC (0.09%; 1/1169) and PPC units (0.06%; 1/1544). Bacteria from skin flora (Propionibacterium acnes, Staphylococcus epidermidis) were the most prevalent contaminants. Median times to first positive culture from start of incubation were 0.7 and 3.7 days in aerobic and anaerobic cultures for confirmed‐positive units. With a “negative‐to‐date” issue strategy, most PC units (55%) had already been issued by time of the first positive culture.CONCLUSION: The rate of confirmed bacterial contamination of PC units was low. Nevertheless, clinicians must be aware of this risk. The risk of bacterial contamination does not warrant universal preference of APCs. It must be questioned whether routine bacterial screening by a culture method can sufficiently prevent contaminated products from being transfused due to the delay until a positive signal in the culture system and due to false‐negative results.
In vitro evaluation of metabolic changes and residual platelet responsiveness in photochemical treated and gamma‐irradiated single‐donor platelet concentrates during long‐term storage
Authors: Apelseth Torunn O. , Bruserud Øystein , Wentzel‐Larsen Tore , Bakken Anne M. , Bjørsvik Solfrid , Hervig Tor 
Published: February 2007

BACKGROUND: Photochemical treatment (PCT) prevents replication of pathogens in platelet concentrates (PCs) by cross‐linking nucleic acids and thus affects all cells containing DNA or RNA.STUDY DESIGN AND METHODS: Fourteen double‐dose single‐donor PCs were divided into two study arms. The double‐dose PCs were split in two identical units, PCT and conventional control PCs. Study Arm A consisted of seven PCT PCs with corresponding untreated controls, whereas Study Arm B consisted of seven PCT PCs with corresponding gamma‐irradiated control. Metabolic changes and agonist‐induced platelet (PLT) response were evaluated during storage for up to 12 days.RESULTS: Higher rate of PLT destruction, illustrated by reduced PLT content, increased lactate dehydrogenase levels, and higher CD61+ microparticle formation rate, were observed after PCT. Generally PCT accelerated metabolic changes in PCs and reduced agonist‐induced (collagen or thrombin receptor activator peptide [TRAP]) aggregation responses. Flow cytometric analysis of CD62P and CD42b (GPIbα) expression showed higher spontaneous PLT activation in PCT PCs from 5 days of storage. Correspondingly, a reduced capacity for up regulation of CD62P expression and down regulation of CD42b was observed in PCT PLTs after stimulation by the agonists ADP or TRAP.CONCLUSION: Generally reduced in vitro PLT quality was observed after PCT during storage for up to 12 days, with marked reduction from 5 days of storage. Compared to conventional PCs, reduced agonist‐induced aggregation and glycoprotein expression were observed after PCT during storage, corresponding to significantly higher level of spontaneous PLT activation in PCT PCs. Clinical studies of efficacy and safety of PCT PCs stored for more than 5 days are recommended.
A practice‐based study on stepwise excavation of deep carious lesions in permanent teeth: a 1‐year follow‐up study
Authors: Bjørndal Lars , Thylstrup Anders 
Published: February 2007

Abstract –This study reports results from a practice‐based study in which deep carious lesions were treated by general dental practitioners using stepwise excavation. The material comprised 94 teeth with deep carious lesions which the clinicians considered would result in pulp perforation if treated by a single and terminal excavation. At therst visit excavation of the peripheral dentine was completed. The outermost part of the central and necrotic dentine was gently removed with a sharp excavator. Standardized assessments of the dentine colour and consistency were made before application of a calcium hydroxide‐containing base material and temporarylling. Thenal excavation was completed after a treatment interval ranging from 2 to 19 months, with a median of 6 months. Reassessments of the dentine colour and consistency were made before complete removal of demineralized dentine. The central dentine was signicantly browner and less softened after the sealing period. After removal of the dark‐brownish dentine during thenal excavation, the colour and consistency of the exposed central dentine was found to resemble that of the completely excavated peripheral dentine. Onlyve cases resulted in pulp perforation during thenal excavation. The high success rate of teeth surviving thenal treatment without pulp exposure after 1 year of observation shows that it was possible for dentists in general practice to administer and manage the treatment of deep carious lesions, a process which may prolong tooth survival compared with conventional endodontic techniques.
Catastrophizing, anxiety and pain during dental hygiene treatment
Authors: Sullivan Michael J. L. , Neish Nancy R. 
Published: February 2007

Abstract – Objectives: This study examined the relations between catastrophizing, dental anxiety, and pain during dental hygiene treatment. Methods: Participants were 78 (32 men, 46 women) consecutive referrals to the Dalhousie University Dental Clinic. All patients were scheduled for a scaling procedure performed by senior dental hygiene students. Following treatment, patients completed the Pain Catastrophizing Scale and the Dental Anxiety Scale – Revised, and were asked to rate the degree of pain they experienced during the scaling procedure. Results: Regression analyses revealed that age and the rumination subscale of the Pain Catastrophizing Scale were signicant predictors of pain, even when controlling for gender, and oral hygiene status. Conclusions: Thendings suggest that excessive focus on pain sensations may be one of the mechanisms by which catastrophizing leads to increased pain. The clinical challenges will be to develop cost‐ and time‐effective means of identifying individuals who catastrophize and to implement interventions to reduce their level of distress.
Prevention and reversal of dental caries: role of low level fluoride
Authors: Featherstone John D. B. 
Published: February 2007

Abstract –Dental caries is a bacterially based disease that progresses when acid produced by bacterial action on dietary fermentable carbohydrates diffuses into the tooth and dissolves the mineral, that is, demineralization. Pathological factors including acidogenic bacteria (mutans streptococci and lactobacilli), salivary dysfunction, and dietary carbohydrates are related to caries progression. Protective factors which include salivary calcium, phosphate and proteins, salivary flow, and fluoride in saliva can balance, prevent or reverse dental caries. Fluoride works primarily via topical mechanisms which include (1) inhibition of demineralization at the crystal surfaces inside the tooth, (2) enhancement of remineralization at the crystal surfaces (the resulting remineralized layer is very resistant to acid attack), and (3) inhibition of bacterial enzymes. Fluoride in drinking water and in fluoride‐containing products reduces tooth decay via these mechanisms. Low but slightly elevated levels of fluoride in saliva and plaque provided from these sources help prevent and reverse caries by inhibiting demineralization and enhancing remineralization. The level of fluoride incorporated into dental mineral by systemic ingestion is insufficient to play a significant role in caries prevention. The effect of systemically ingested fluoride on caries is minimal. Fluoride “supplements” can be best used as a topical delivery system by sucking or chewing tablets or lozenges prior to ingestion.
Oral health‐related quality of life of periodontal patients
Authors: Cunha‐Cruz J. , Hujoel P. P , Kressin N. R. 
Published: February 2007

Background and Objective:  The purpose of this study was to assess the oral health‐related quality of life of patients presenting to a periodontal specialist by means of six questions, and to assess the perceived oral health by means of one question. Self‐assessments of oral health were associated with clinical characteristics.Material and Methods:  Logistic regression models were used to associate self‐assessments with clinical characteristics in a cross‐sectional study.Results:  On the six‐item questionnaire, close to 20% (295/1480) of the patients reported that teeth, gums or dentures had an impact fairly often or very often on one or more items (eating, relaxing, avoiding going out, feeling self‐conscious, pain or discomfort). On the single question requesting a self‐assessment of oral health, 42% (628/1468) rated their oral health as fair or poor. Both common oral health‐related quality of life problems and worse perceived oral health were associated with having more than eight teeth with >5 mm periodontal pockets (odds ratio = 1.45, 95% confidence interval = 1.01–2.08; and odds ratio = 2.83, 95% confidence interval = 2.08–3.84, respectively), compared with patients who had fewer than three teeth with >5 mm periodontal pockets.Conclusion:  Oral health‐related problems in patients presenting to a periodontal specialist office negatively affect their quality of life. If some of the findings of this study can be confirmed in other studies, it could change the perception of chronic periodontitis as a silent disease.
Objective evaluation of skin prick test reactions using digital photography
Authors: Vieira dos Santos Rosaly , Titus Richard G. , Cavalcante Lima Hermênio 
Published: February 2007

Background: The skin prick test has been used worldwide to determine IgE‐mediated hypersensitivity. However, the most current method to record this reaction has problems with accuracy and precision.Objective: To demonstrate a new approach to measure the skin prick reaction and its kinetics with precision.Methods: The skin prick test was induced using histamine or Dermatophagoides pteronyssinus antigen in 80 volunteers aged 4 and 67 years who had different skin colors. Digital photographs were obtained at 0, 3, 5, 10, 15 and 20 min. The mean wheal and erythema area as well as the erythema intensity were determined using Adobe Photoshop® software. The accuracy and precision of this approach were also evaluated.Results: The digital photographic analysis measured the wheal and erythema sizes independent of the antigen or skin color with precision. In addition, a new variable of this test, the skin erythema intensity, could be determined objectively using the chromaticity of reflected light.Conclusions: Digital photographic analysis is a precise and objective method to evaluate the skin prick test reaction, which can be used independent of the patient's skin color in clinical or research settings.
Relationships between visual and tactile features and biophysical parameters in human facial skin
Authors: Ambroisine Laurence , Ezzedine Khaled , Elfakir Anissa , Gardinier Sophie , Latreille Julie , Mauger Emmanuelle , Tenenhaus Michel , Guinot Christiane 
Published: February 2007

Background/purpose: Skin properties, such as colour, hydration and texture, can be studied on a qualitative basis by a clinical assessment or on a quantitative basis using techniques that measure biophysical properties of the skin. The aim of this study was to explore the links between facial skin features and a range of skin biophysical parameters using multivariate methods.Methods: A study was conducted on 256 female volunteers from Ile‐de‐France with apparent healthy skin, aged between 20 and 50, under controlled environmental conditions (mean±standard deviation: room temperature 22.9±0.3°C; relative humidity 48.5±2.3%). The study included a medical questionnaire and a clinical examination of the skin performed by a dermatologist, and a biophysical evaluation of the skin properties. Seventy visual and tactile skin features were assessed on the forehead and the cheek using ordinal variables illustrated by photographic scales. Twenty‐eight biophysical measurements were taken in the same areas using the following equipment: Chromameter®, Evaporimeter®, Corneometer®, Skicon®, Sebumeter®, Sebutape®, skin thermometer, skin pH‐meter and Silflo®. In order to group the variables illustrating a same unimodal phenomenon, a typology of the skin features and a typology of the biophysical parameters were carried out using a clustering method. Then, the relationships between each group of clinical features and each group of biophysical parameters were studied using a series of partial least squares (PLS) regressions.Results: From eight groups of clinical features and three groups of biophysical parameters that were identified, 12 significant PLS regression models were built. Our findings suggest that differences in chromametric measurements express not only differences in skin colour but also differences in skin surface properties, such as skin vascularity status, thickness, and existence of wrinkles, and also demonstrate that the level of sebum excretion can affect other aspects of the skin surface.Conclusion: Some skin features assessed clinically do not appear to be linked to any biophysical parameter. This finding confirms that certain phenomena evaluated on the basis of visual or tactile skin features are not assessed on the basis of the biophysical properties of the skin measured by our bioengineering techniques. Indeed, visual skin features mainly appreciate the skin surface aspect, contrary to some biophysical surrogate markers known to provide information on underlying epidermal structures. Therefore, both clinical and biophysical assessments must be associated to supply a relevant and accurate approach for skin aspect characterisation.
Application of optical non‐invasive methods in skin physiology: a comparison of laser scanning microscopy and optical coherent tomography with histological analysis
Authors: Lademann Juergen , Otberg Nina , Richter Heike , Meyer Lars , Audring Heike , Teichmann Alexa , Thomas Steven , Knüttel Alexander , Sterry Wolfram 
Published: February 2007

Background/purpose: Optical, non‐invasive methods, such as fluorescence laser scanning microscopy (LSM) and optical coherent tomography (OCT), have become efficient tools for the characterization of the skin structure in vivo, as well as real‐time investigation of distribution and penetration of topically applied substances.Methods: In the present paper, the results obtained with both non‐invasive methods – OCT and LSM – were compared to conventional light microscopy of histological sections. Skin structure and the distribution of topically applied particulate and non‐particulate substances on the skin surface and in the epidermis were analyzed.Results: None of the methods used are suitable for the realization of all diagnostic tasks, however, each method has advantages for particular applications. Fluorescence LSM is well suited for the investigation of the upper 150 μm of the skin as well as for the investigation of the kinetics of substances applied onto or into the epidermis. OCT can be applied for the investigation of vertical cross‐sections of the skin up to a depth of 2 mm, albeit at lower resolution than achieved by LSM or conventional light microscopy. Conventional light microscopy of histological sections of biopsy specimens produces familiar high‐resolution images of deeper tissue layers. However, the analysis of the kinetic processes is limited in this case.Conclusions: LSM‐ and OCT‐measurements are efficient non‐invasive tools for the characterization of morphological structures of the skin. On the one hand, the optical methods have a clear advantage in the case of kinetic measurements. On the other hand, histological investigations are characterized by a high information density and a high resolution, also in deep tissue layers. The selection of the best method for the analysis of the skin morphology depends on the target and the task of the investigation.
Skin phosphocreatine
Authors: Zemtsov Alexander 
Published: February 2007

Background/purpose: The skin has the unique ability to survive ischemia associated with skin grafts, flaps and hair transplantation procedures. Spectroscopic data later confirmed by chromatography, immunohistochemistry and molecular biology techniques identified the presence of large quantities of phosphocreatine in human skin. Phosphocreatine molecules regenerate ATP cellular reserves during ischemia. This reaction is mediated by creatine phosphokinase enzymes that were also isolated and studied in normal and diseased skin.Methods: Literature search revealed important contributions by US, Swiss, German, French, Scandinavian and Japanese investigators in the development and understanding of this research field.Results: Serum creatine phosphokinase levels are elevated in burn victims and patients with toxic epidermal necrolysis. Phosphocreatine concentration and creatine phosphokinase activity are elevated in psoriatic skin and in non‐melanoma malignancies in comparison with normal skin. Furthermore, skin phosphocreatine and creatine phosphokinase enzymes are localized almost exclusively within the epidermis and in hair follicles. Finally, phosphocreatine and creatine phosphokinase enzymes help to protect skin from UV damage.Conclusions: Clearly, this research area is only starting to be appreciated by the scientific community. Topical and systemic phosphocreatine administration appears to reverse photodamage and improve wound healing. Spectroscopic monitoring of phosphocreatine and related phosphometabolites can be potentially used to monitor disease activity and respond to therapy in psoriasis, leg ulcers, skin malignancies and other skin conditions.
Skin friction blistering: computer model
Authors: Xing Malcolm , Pan Ning , Zhong Wen , Maibach Howard 
Published: February 2007

Background/purpose: Friction blisters, a common injury in sports and military operations, can adversely effect or even halt performance. Given its frequency and hazardous nature, recent research efforts appear limited. Blistering can be treated as a delamination phenomenon; similar issues in materials science have been extensively investigated in theory and experiment. An obstacle in studying blistering is the difficulty of conducting experiment on humans and animals. Computer modeling thus becomes a preferred tool.Method: This paper used a dynamic non‐linear finite‐element model with a blister‐characterized structure and contact algorithm for outer materials and blister roof to investigate the effects on deformation and stress of an existing blister by changing the friction coefficient and elastic modulus of the material in contact with the blister.Results: Through the dynamics mode and harmonic frequency approach, we demonstrated that the loading frequency leads to dramatic changes of displacement and stress in spite of otherwise similar loading. Our simulations show that an increased friction coefficient does not necessarily result in an increase in either the stress on the hot spot or blister deformation; local maximum friction stress and Von Mises stress exist for some friction coefficients over the wide range examined here. In addition, the stiffness of contact material on blistering is also investigated, and no significant effects on deformation and Von Mises stress are found, again at the range used. The model and method provided here may be useful for evaluating loading environments and contact materials in reducing blistering incidents.Conclusion: The coupling finite‐element model can predict the effects of friction coefficient and contacting materials&apos stiffness on blister deformation and hot spot stress.
A Study on Variances in Multivariate Analyses of Oral Implant Outcome
Authors: Herrmann Irene , Kultje Christina , Holm Sture , Lekholm Ulf 
Published: February 2007

ABSTRACTBackground:  Elaborate studies have shown that interdependency exists between implants being placed in the same patient/jaw. Therefore, interdependency ought to be an important aspect to address, whenever performing statistical analyses of oral implant outcomes. A Jackknife method could be an option when conducting statistical evaluations of oral implant failure prognoses.Purpose:  The aim of this study was to evaluate whether a statistical difference can be detected by using the Jackknife method in conjunction with life table analyses and/or a log rank test of four different combinations of jaw density and quantity.Materials and Methods:  Four multicenter studies were pooled and adjusted in order to create a research database consisting of 486 patients and 1,737 implants in preparation for the Jackknife resampling method. Combinations of jaw shapes and bone qualities were constructed to select at‐risk patients.Statistical Methods:  Life tables with confidence intervals were calculated and a log rank test was used to determine whether a statistical difference between the combinations could be established.Results:  Both statistical analyses, after the Jackknife resampling method, showed that patients with poor bone quality and resorbed jaws (combination IV) had a statistically higher risk of implant failure.Conclusion:  By rearranging data using the Jackknife method, standardized statistical tests seem to work well even when the study population tested was affected by interdependency.