bluuebunny/crossref_metadata_2025 huggingface dataset:
Transition metal abundances in microbial carbonate: a pilot study based onin situLA‐ICP‐MS analysis
Authors: KAMBER BALZ S. , WEBB GREGORY E.
Published: October 2007

The ability to recognize the former existence of microbes as well as the biological origin of marine precipitates, such as putative microbialites, is crucial for understanding the development and history of early life on Earth. Increasingly, such rocks hold keys to understanding the geochemical evolution of the oceans and linked Earth systems. Vital trace elements previously have received relatively little attention as clues to the origin of carbonate rocks, and low abundance transition elements in particular, have been difficult to analyse in carbonate matrices for technical reasons. We have used laser ablation–inductively coupled plasma–mass spectroscopy for thein situmeasurement of a broad suite of vital transition metals in Late Devonian reefal limestones that contain coeval microbialite (the calcimicrobeRenalcis), stromatoporoid sponge skeleton, early marine cement, and later diagenetic cement. Comparative experiments conducted in two different ion extraction modes determined theoretical detection limits for transition elements on NIST reference material SRM 612. Analyses of NIST glasses SRM 614 and 616 demonstrate accuracy relative to previously published data. On that basis we have identified significant enrichment of the vital elements V, Sn, Cu and Zn within theRenalcis. The stromatoporoid skeleton by contrast is enriched only in V. Earliest cements, which also may have been mediated to some degree by microbial biofilms on the basis of their morphology, show a much smaller degree of enrichment, and later cements show no enrichment, with the exception of Zn, which is concentrated in the latest cement. Fine particulate carbonate sediments (micrite) show variable metal enrichments that are attributable to varying contributions from detrital siliciclastic contamination.Renalciswas also enriched above the sponge and cements in regards to Mn, Cd, Co, and possibly Cr, but at less robust levels. Molybdenum and Sb were found not to be enriched in theRenalcis, and Ni, although clearly very low in concentration, could not be evaluated owing to its high detection limit. We additionally were able to identify specific zones of contamination inRenalcisencountered as the laser drilled deeper into the carbonate. Time resolved analysis allows exclusion of such contaminants from integration into the results. Successful application of the new technique will now allow us to assess metal uptake in ancient carbonates with implications for interpreting the biogenicity of putative microbialites.
Telomere length predicts survival independent of genetic influences
Authors: Bakaysa Stephanie L. , Mucci Lorelei A. , Slagboom P. Eline , Boomsma Dorret I. , McClearn Gerald E. , Johansson Boo , Pedersen Nancy L.
Published: October 2007

Telomeres prevent the loss of coding genetic material during chromosomal replication. Previous research suggests that shorter telomere length may be associated with lower survival. Because genetic factors are important for individual differences in both telomere length and mortality, this association could reflect genetic or environmental pleiotropy rather than a direct biological effect of telomeres. We demonstrate through within‐pair analyses of Swedish twins that telomere length at advanced age is a biomarker that predicts survival beyond the impact of early familial environment and genetic factors in common with telomere length and mortality. Twins with the shortest telomeres had a three times greater risk of death during the follow‐up period than their co‐twins with the longest telomere measurements [hazard ratio (RR) = 2.8, 95% confidence interval 1.1–7.3, P = 0.03].
CARDIOVASCULAR AND SURVIVAL PARADOXES IN DIALYSIS PATIENTS: The Cholesterol Paradox Is Flawed; Cholesterol Must Be Lowered in Dialysis Patients
Authors: Wan Ray K. , Mark Patrick B. , Jardine Alan G.
Published: October 2007

In the general population, elevated cholesterol is associated with cardiovascular disease and mortality and lowering cholesterol is associated with improved outcomes. This reflects the predominance of isolated atherosclerotic coronary disease in the general population. In patients with renal disease, however, the relationship between serum lipids and cardiovascular outcomes is much less clear and even reversed. In our opinion, the relationship between cholesterol and coronary disease is obscured by high levels of co‐morbid disease, malnutrition, inflammation, atypical dyslipidemia and the fact that myocardial infarction is not the typical presentation of cardiovascular disease in patients with renal disease. Thus, cholesterol lowering will still be effective in patients with chronic kidney diseases.
Vascular Access Outcomes in the Elderly Hemodialysis Population: A USRDS Study
Authors: Chan Micah R. , Sanchez Robert J. , Young Henry N. , Yevzlin Alexander S.
Published: October 2007

Arteriovenous fistulae (AVF) are widely regarded as the preferred vascular access in hemodialysis (HD) patients due to their primary patency and patient survival benefits. Recent scholarship has suggested that the elderly population differs significantly from the general population in terms of inflammatory markers. What is more, recent studies have suggested that the elderly HD population is less likely to have an AVF placed as the initial vascular access compared to a younger cohort. The purpose of this study is to investigate the applicability of current vascular access guidelines to the elderly HD population. We hypothesized that the elderly HD population would derive less patency and survival benefit from AVF placement relative to arteriovenous graft (AVG) than the general population is known to derive. We performed a retrospective analysis using the US Renal Data System (USRDS) Wave II dataset to explore significant predictors of referral for intervention or access failure, and patient survival in the elderly US HD population using Cox regression corrected for race, gender, peripheral vascular disease, diabetes mellitus, and nutritional status. Of the 1471 HD patients with AVF or AVG, 764 patients were >65 years. Elderly diabetics had no significant mortality benefit from the use of AVF compared to AVG [odds ratio (OR) 1.34 (95% CI 0.92–1.95), p = 0.123]. Likewise, elderly nondiabetics had no significant mortality benefit from the use of AVF compared to AVG [OR 1.05 (95% CI 0.81–1.36), p = 0.735]. Elderly diabetics had no difference in odds for intervention referral for AVF compared to AVG [OR 1.49 (95% CI 0.76–2.9), p = 0.24]. Elderly nondiabetics had no difference in odds for intervention referral for AVF compared to AVG [OR 1.48 (95% CI 0.95–2.3), p = 0.08]. We conclude that the potential benefits derived from AVFs compared with AVGs and central venous catheters (CVC) may not apply universally. The recommendations of vascular access choice stipulated by national guidelines may need to be modified for elderly patients.
The Role of Medical Directors in Dialysis Facilities Series Editor: Robert A. Gutman: The Role of the Medical Director: Changing with the Times
Authors: Maddux Franklin W. , Maddux Dugan W. , Hakim Raymond M.
Published: October 2007

The role of the dialysis unit Medical Director has evolved over time to an expanded set of roles from one that used to be strictly “medical” to one that is more “managerial.” Physicians providing these Medical Director services are facing increasing demands for a leadership role regarding clinical quality improvement and measurement of performance in core areas of care within the dialysis program. The dialysis Medical Director is asked to lead in group decision‐making, in analyzing core process and patient outcomes and in stimulating a team approach to Continuous Quality Improvement (CQI) and patient safety. For the end‐stage renal disease program, national quality expectations in dialysis care have stimulated the dialysis providers to measure, report and respond consistently in an effort to provide a higher level of cost‐efficient care. Medical Directors are usually contractually linked to the dialysis programs for which they provide oversight and their contracts are explicit about the relationship they maintain and the role they are expected to play within dialysis companies (often called “provider organizations”). The evolution of the Medical Director role has led to a close relationship between the company that provides the dialysis services and the physician providing the medical oversight.
Efficacy of Folic Acid in Children With Migraine, Hyperhomocysteinemia and MTHFR Polymorphisms
Authors: Di Rosa Gabriella , Attinà Sarina , Spanò Maria , Ingegneri Giulia , Sgrò Domenica L. , Pustorino Giuseppina , Bonsignore Maria , Trapani‐Lombardo Vincenzo , Tortorella Gaetano
Published: October 2007

MTHFR gene variants C677T and A1298C seem to be related to an increased risk of migraine. Folates' metabolism could play a role in the pathophysiology of migraine. We supplemented 16 children with migraine, hyperhomocysteinemia, and MTHFR polymorphisms with folic acid and obtained a resolution/reduction of migraine attacks. Although the mechanism leading to these effects has been not made clear, we believe that the use of folic acid needs further investigations in migraineurs with hyperhomocysteinemia and MTHFR variants. A randomized, double‐blind, placebo controlled crossover trial is needed to support these findings.
Hemicrania Continua‐Like Headache due to Nonmetastatic Lung Cancer—A Vagal Cephalalgia
Authors: Evans Randolph W.
Published: October 2007

A 72‐year‐old man presented with a 7‐week history of a new onset constant severe right‐sided headache associated with redness and tearing of the right eye, which resolved on indomethacin due to nonmetastatic small cell carcinoma producing a large suprahilar mass. This is the first case report of a hemicrania continua‐like headache with autonomic features due to lung cancer. I propose the term “vagal cephalalgia” to include headache and/or facial pain due to nonmetastatic lung cancer and cardiac cephalalgia which result from vagal afferent stimulation.
Networking as a Means to Strategy Change: The Case of Open Innovation in Mobile Telephony
Authors: Dittrich Koen , Duysters Geert
Published: October 2007

The purpose of this article is to investigate how innovation networks can be used to deal with a changing technological environment. This study combines different concepts related to research and development (R&D) collaboration strategies of large firms and applies these concepts to R&D alliance projects undertaken by Nokia Corporation in the period 1985–2002. The research methodology is a combination of in‐depth semistructured interviews and a large‐scale quantitative analysis of alliance agreements. For the empirical analysis a distinction is made between exploration and exploitation in innovation networks in terms of three different measures. As a first measure, the difference between exploration and exploitation strategies by means of the observed capabilities of the partners of the contracting firms is investigated. The second measure is related to partner turnover. The present article argues that in exploration networks partner turnover will be higher than in exploitation networks. As a third measure, the type of alliance contract will be taken; exploration networks will make use of flexible legal organizational structures, whereas exploitation alliances are associated with legal structures that enable long‐term collaboration. The case of Nokia has illustrated the importance of strategic technology networks for strategic repositioning under conditions of change. Nokia followed an exploitation strategy in the development of the first two generations of mobile telephony and an exploration strategy in the development of technologies for the third generation. Such interfirm networks seem to offer flexibility, speed, innovation, and the ability to adjust smoothly to changing market conditions and new strategic opportunities. These two different strategies have led to distinctly different international innovation networks, have helped the company in becoming a world leader in the mobile phone industry, and have enabled it to sustain that position in a radically changed technological environment. This study also illustrates that Nokia effectively uses an open innovation strategy in the development of new products and services and in setting technology standards for current and future use of mobile communication applications. This article presents one of the first longitudinal studies, which describes the use of innovation networks as a means to adapt swiftly to changing market conditions and strategic change. This study contributes to the emerging, but still inconsistent, literature on explorative and exploitative learning by means of strategic technology networks.
Multibranded Platform Development: A Corporate Strategy with Multimanagerial Challenges
Authors: Sköld Martin , Karlsson Christer
Published: October 2007

Product platforms have become a principal fundament and a prerequisite for profitable product development in almost every industry today. Since platforms have a desirable potential to reduce development and production costs, there is an extensive bulk of knowledge describing underlying platform principles and challenges. But the vast majority of the identified challenges are based on single firms and brand contexts, which imply that previous findings might not be applicable when platform development involves several brands, here called multibranded platforms. In the present article it is therefore suggested that there is lack of knowledge describing managerial challenges of multibranded platform development. To be able to capture such a strategy that holds certain complexity and unknown dimension, an explorative and longitudinal field study is supposed to achieve the finest insights into a yet incompletely documented phenomenon. Because of the field‐study approach, findings from the study are theoretically validated in relation to existing knowledge from other contributions. To start developing a multibranded product platform development framework, the present study identifies three distinctively different strategic forces that must be handled in such multibranded platform development: (1) the creation of a common architecture; (2) accomplishing product differentiation within an expanded and multibranded product scope; and (3) corporate responsibility in the transition from single‐branded to multibranded platform development. Three dimensions of managerial challenges are identified. The first is technology management challenges, which deal with commonalization in terms of the development of common multibranded architectures. The major challenge to achieve architectural commonalization is that no individuals from any brand have the proper multibranded architectural knowledge. Instead, multibranded architectures must evolve from the beginning and be founded on a new and expanded brand scope. Architectural commonalization also includes elements of unlearning since previous experiences have little relevance. The second challenge is brand management challenges and deals with brand differentiation in terms of portfolio management. Differentiation is an effect of increased diversification that particularly challenges brands of opposite generic competitive strategies. The third challenge dimension is called corporate management challenges and deals with the combination of the two others. From a corporate management perspective, it seems important to provide new organizational structures that support and combine interests of technology and brand management. Finally, multibranded platform development is a corporate strategy that affects business units and functional units thoroughly.
Determinants of IT Usage and New Product Performance*
Authors: Barczak Gloria , Sultan Fareena , Hultink Erik Jan
Published: October 2007

Explosive growth of information technologies (IT) has prompted interest in examining the role of IT in new product development (NPD). Through desktop software and Web‐based tools, IT has been used to aid idea generation and product testing as well as for NPD activities such as process and portfolio management. Recent research suggests, however, that a gap exists between IT availability and usage. Given the importance of IT in creating business value through the development of new products and services, the present study seeks to identify factors that affect IT usage. Further, anecdotal evidence and conceptual studies intimate that the usage of IT tools for NPD can shorten time to market, can improve product quality, and can increase productivity. However, empirical substantiation of this impact is mostly nonexistent. The current study investigates the relationship between IT usage and two measures of new product performance: speed to market and market performance. Employing a mail‐survey methodology, the study uses data from a sample of practitioner members from the Product Development & Management Association to examine the effect of project risk, existence of a champion, autonomy, innovative climate, IT infrastructure, and IT embeddedness on the extent of IT usage. These data are also used to explore the impact of IT usage on speed to market and market performance. The results indicate that project risk, existence of a champion, and IT embeddedness positively affect the extent of IT usage for NPD. Additionally, IT usage positively and significantly influences the performance of the new product in the marketplace. Surprisingly, and contrary to popular belief, IT usage does not have any impact on speed to market. An important implication of this study is that IT usage influences performance but not in the way managers expect. Specifically, IT usage does not seem to affect speed to market but rather positively impacts the performance of the new product in the marketplace. This result suggests that IT usage in NPD provides far more value to firms than previously thought and provides evidence to support greater investments in IT for product development efforts. Other implications of the study are that unless IT is embedded into the NPD process and champions for IT tools exist, chances are that IT will not be used and its benefits will not be realized.
Innovation Games: Creating Breakthrough Products through Collaborative Play by Luke Hohmann
Authors: Brodie Christina Hepener
Published: October 2007

Books reviewed in this issue:

Innovation Games: Creating Breakthrough Products through Collaborative Play

Dragons at Your Door: How Chinese Cost Innovation Is Disrupting Global Competition

Naked Conversations: How Blogs Are Changing the Way Businesses Talk with Customers

The Innovation Killer: How What We Know Limits What We Can Imagine and What Smart Companies Are Doing about It

Innovation on Demand: New Product Development Using TRIZ
Superior Cardiac Hemodynamics of Atrioventricular Synchrony Over Rate Responsive Pacing at Submaximal Exercise: Observations in Activity Sensing DDDR Pacemakers
Authors: LAU CHU‐PAK , WONG CHEUK‐KIT , LEUNG WING‐HUNG , LIU WEN‐XIU
Published: October 2007

LAU, C.‐P., ET AL.: Superior Cardiac Hemodynamics of Atrioventricular Synchrony Over Rate Responsive Pacing at Submaximal Exercise: Observations in Activity Sensing DDDR Pacemakers. The relative hemodynamic profile between dual chamber pacing (DDD) and activity sensing rate responsive pacing (VVIR) was compared in ten patients with dual chamber rate responsive pacemakers (Synergist 11). With a double blind, randomized exercise protocol, DDDR pacemakers were programmed into VVI, VVIR, and DDD (AV interval 150 msec) modes and in seven patients the test in the DDD mode was repeated with the AV interval programmed at 75 msec. A treadmill exercise test of 6‐minutes duration (2 stages, Stage 1 at 2 mph, 0% gradient and Stage II at 2 mph, 15% gradient) was performed at each of the programmed settings, with a rest period of 30 minutes in between tests. Cardiac output was assessed using continuous‐wave Doppler sampling ascending aortic flow and expressed as a percentage of the value achieved during VVI pacing. During exercise, pacing rate between DDD and VVIR pacing was similar but was higher with DDD at the first minute of recovery (91 ± 4vs 81 ± 3 beat/min, respectively). Cardiac output was significantly higher at rest, during low level exercise, and recovery with DDD pacing compared with VVIR pacing (resting: 21 ± 14 vs ‐2 ± 7%; Stage I: 36 ± 6 vs 16 ± 7%; Stage II: 25 ± 15 vs 10 ± 8%; recovery: 26 ± 12 vs 4 ± 9%; p < 0.05 in all cases). Systolic blood pressure was significantly higher during low level of exercise in the DDD mode. Shortening of the AV interval to 75 msec did not significantly affect cardiac output during exercise, but cardiac output after exercise was reduced (2 ± 6 vs 23 ± 6% at an AV interval of 150 msec, p < 0.02). By enhancing the stroke volume, DDD pacing improves cardiac hemodynamics at rest, during low level exercise, and early postexercise recovery.
Chronic Ventricular Electrograms: Do Steroid‐Eluting Leads differ from Conventional Leads?
Authors: SCHUCHERT ANDREAS , HOPF MICHAEL , KUCK KARL HEINZ , BLEIFELD WALTER
Published: October 2007

SCHUCHERT, A., ET AL.: Chronic Ventricular Electrograms: Do Steroid‐Eluting Leads differ from Conventional Leads? The aim of steroid‐eluting leads is to reduce chronic pacing thresholds. Whether steroid‐eluting leads also modify acute and chronic R wave amplitudes as well as R wave sensing of the pulse generator was investigated in 31 patients with a unipolar ventricular pacemaker. Four different leads were implanted: Two steroid‐eluting leads with different electrode surface areas (8 mm2 and 5.8 mm2) and two conventional leads (Target Tip, Elgiloy lead). At implantation filtered R wave amplitudes, peak‐to‐peak values, and slew rates were measured by a pacing system analyzer. One year after implantation R wave amplitudes were directly determined from intracardiac electrograms and compared to the peak‐to‐peak data at implantation. Additionally, R wave inhibition was evaluated at a sensitivity setting of 5 mV. There were no differences among the four leads in respect to any of the parameters studied at implantation. At follow‐up, no differences in R wave amplitudes were found leading to an appropriate sensing in all leads. Steroid‐eluting leads did not differ from conventional leads and a smaller electrode surface area of 5.8 mm2 had no influence on ventricular electrogram. Together with a pacemaker with an input impedance of 37 kohms R wave sensing was a correct setting of 5 mV.
A New Efficient NanoTip Lead
Authors: STOKES KEN , BIRD TERI
Published: October 2007

STOKES, K., ET AL.: A New Efficient NanoTip Lead. The ideal lead has low, stable acute and chronic thresholds, high pacing impedance, and good sensing. Leads with low, stable thresholds have been developed, but pacing impedance has been in the 600 Ω region. One way to increase pacing impedance is to decrease the electrode's surface area. The threshold performance and sensing ability of < 5 mm2 electrodes have been considered questionable, up to now. We have developed α 1.5 mm2 porous, platinized, steroid‐eluting electrode and have demonstrated in canine studies that it has excellent performance. Chronic thresholds are low at about 0.65 ± 0.28 V (ventricular) and 0.42 ± 0.12 V (atrial) at 0.5 msec. Chronic pacing impedance is in the 1200–1300 Ω region, but mean chronic R and P wave source impedance is ≤ 1500 Ω. Sensing is excellent, with almost double the P wave amplitudes usually measured in the canine.
Diagnosis of ICD Lead Failure Using Continuous Event Marker Recording
Authors: HORTON RODNEY P. , CANBY ROBERT C. , ROMÁN CARLOS A. , JESSEN MICHAEL E. , SCHULTE THEODORE J. , PAGE RICHARD L.
Published: October 2007

HORTON, R.P., et.al.: Diagnosis of ICD Lead Failure Using Continuous Event Marker Recording. Stored electrograms enhance the ability to evaluate therapy episodes in the third‐generation implantable cardioverter defibrillator. These electrograms are recorded from either the shocking or rate sensing leads, but not both. As a result, differentiation of certain types of sensing abnormalities may be difficult prior to surgical exploration. We present a case of rate sensing lead failure due to an insulation break. Several minutes of recording of the event marker in the laboratory failed to document any abnormal sensing; the diagnosis was made by recording the event marker on a 24‐hour continuous (Holter) monitor. The Holter monitor/event marker combination was of substantial diagnostic value and allowed for a more focused surgical evaluation and treatment.
Nodular pulmonary amyloidosis and Sjögren's syndrome in a patient treated with intermittent hemodialysis
Authors: NIEPOLSKI Leszek , GRZEGORZEWSKA Alicja E. , SZYMAŚ Janusz
Published: October 2007

In the available literature, we have found the descriptions of 5 cases of nodular pulmonary amyloidosis associated with Sjögren's syndrome. In our practice, such a case has occurred in a patient with chronic renal failure. A 53‐year‐old woman underwent nephrological, rheumatological, and pulmonological examinations because of end‐stage renal disease with a small cirrhotic kidney in renal ultrasound examination, pulmonary nodules, and xerophthalmia. Serological data revealed a slightly positive rheumatoid factor, antinuclear antibodies, anti‐SS‐A, anti‐SS‐B, and anti‐RNP/Sm antibodies. Schirmer's test was positive on both sides and Sjögren's syndrome was recognized. Pulmonological examinations (the chest radiograph and CT scan, bronchofiberoscopy, culture of bronchial washings, bronchial biopsy, pleural effusion analysis, and a thick‐needle biopsy) failed to determine the etiology of nodular changes in lungs. Immunofluorescence studies in the skin biopsy specimen showed IgM‐positive staining. After 2 years of treatment with IHD, a toracoscopy was performed with enucleation of the nodules from the right lung. Histological examination showed massive deposits of amyloid, which allowed for a diagnosis of diffusive nodular pulmonary amyloidosis.
Effects of Reduction Treatment on Fracture Properties of Cerium Oxide
Authors: Wang Yanli , Duncan Keith L. , Wachsman Eric D. , Ebrahimi Fereshteh
Published: October 2007

The reduction treatment effects on the flexural strength and the fracture toughness of ceria were evaluated at room temperature. The results reveal that the flexural strength decreases significantly after reduction under very low oxygen partial pressures; however, in contrast, fracture toughness is increased by 30%–40% when the oxygen partial pressure was decreased to 10−20–10−22 atm range. The large microcracks and the surface tensile stresses developed upon reduction treatment and cooling process are responsible for the decreased strength. The enhancement in toughness is also discussed in terms of internal stresses, microcrack toughening, and crack deflection mechanisms.
Spatial dynamics of aSirex noctiliowoodwasp population within a pine plantation in Patagonia, Argentina
Authors: Corley Juan C. , Villacide José M. , Bruzzone Octavio A.
Published: October 2007

The woodwaspSirex noctilioF. (Hymenoptera: Siricidae) is probably the most important pest of pine tree plantations of the southern hemisphere. We studied the spatial arrangement of an endemic population of the woodwaspS. noctiliowithin pine plantations located in northwest Patagonia, Argentina, during three successive years since colonization. By censusing healthy and attacked trees, which provided data on current and past yearly woodwasp attacks, we studied: (i) the spatial pattern of attacked trees during the endemic phase of a woodwasp population, and (ii) the changes in the spatial arrangement through time and with an increasing (i.e., no intervention) pest population. Among a total of 53 649 counted trees, attack rates were low during the study period (accumulated attack below 0.5%). Results of spatial statistical analysis showed that woodwasp attack is highly clumped, and that spatial aggregation increases with time, even with increasing numbers of attacked trees. The observed spatial arrangement, a consequence of a demographic process, can have important implications for the management of woodwasp populations and contributes to our understanding of the nature of outbreak population behaviour in this pestiferous forest insect.
Postoperative surveillance, registration and classification of wound infection in cardiac surgery—experiences from Great Britain
Authors: WILSON A. P. R.
Published: October 2007

Wound infection in cardiac surgery is a continuing problem despite improvements in surgical technique. The risk factors for, and appearance of, the infected wound differ from operations in other specialties. A robust definition is required for successful surveillance but many are open to different interpretations. At UCLH, comparison between UK and US definitions shows marked differences in patients defined as infected. Surveillance with feedback is effective if conducted over several years, but a high proportion of infected wounds are only identified during post‐discharge follow‐up. Deteriorating performance of an individual surgeon can be detected and interventions focused on improving faults identified during data collection. Often highlighting the problem is sufficient to reverse the trend, but the process of audit and control is becoming more important as accountability and performance is demanded by primary care providers and patients.
Modified prophylaxis for preventing deep sternal wound infection after cardiac surgery
Authors: SCHERSTEN HENRIK
Published: October 2007

In order to prevent deep sternal wound infection after cardiac surgery we decided at the Sahlgrenska University Hospital to revise our protocol for antibiotic prophylaxis by adding an application of local collagen‐gentamicin between the sternum halves to our standard prophylaxis. In addition, we focused specifically on the wiring technique. This quite simple modification of the prophylaxis program has been successful. The infection rate during 2006 is the lowest rate we have recorded since we started measuring it in 1995. We conclude that with application of local collagen‐gentamicin and modification of the sternal closure method we have been able to significantly decrease the incidence of wound infections after cardiac surgery.
Postoperative surgical site infections in cardiac surgery —an overview of preventive measures
Authors: GÅRDLUND BENGT
Published: October 2007

Postoperative surgical site infections are a major cause of postoperative morbidity and mortality in cardiac surgery. A surgical site infection occurs when the contaminating pathogens overcome the host defense systems and an infectious process begins. Bacteria may enter the operating site either by direct contamination from the patient's skin or internal organs, through the hands and instruments of the surgical staff or by bacteria‐carrying particles that float around in the operating theatre and may land in the wound. The ability to withstand the contaminating bacteria depends on both local and systemic host defense. Successful preventive strategies are multiple and must include: 1) Minimizing the bacterial contamination of the surgical site (skin preparation, operating room ventilation, scrubbing, double gloving, etc.), 2) Minimizing the consequences of virulent contaminating bacteria by antibiotic prophylaxis (adequate dose, sort, timing, duration), 3) Minimizing injury to local host defense (atraumatic surgery, no excessive electrocautery, meticulous hemostasis, etc.), and 4) Optimizing general host defense (nutrition, tobacco smoking, weight loss, etc.). Compliance with these preventive procedures must be enforced through regular reviews of performance. Non‐compliance with hygiene routines is often due to ignorance and poor planning. Education of personnel in these issues is a continuous process.
Immunohistochemical detection of XIAP in melanoma
Authors: Emanuel Patrick O. M. , Phelps Robert G. , Mudgil Adarsh , Shafir Michail , Burstein David E.
Published: October 2007

Background:  The X‐linked inhibitor of apoptosis protein (XIAP) is the most potent of the inhibitor of apoptosis family of eight proteins. High levels of XIAP have been found in melanoma cell lines and are believed to play a role in therapeutic resistance in a number of malignancies. XIAP expression has not been investigated in clinically obtained melanoma tissue samples, nor have studies attempted to correlate XIAP expression with prognostic variables or clinical aggressiveness of melanomas.

Methods:  Sixty‐seven patients with primary cutaneous malignant melanoma for whom clinical follow up was available were identified from the records of the Mount Sinai Hospital, comprising 37 thin melanomas (Breslow thickness < 1.0 mm) and 30 thick melanomas (Breslow thickness > 1.0 mm). Archival paraffin sections from primary lesions and corresponding metastases were stained with monoclonal anti‐XIAP antibody using routine immunohistochemical methods.

Results:  Six benign intradermal nevi and four in situ melanomas were XIAP negative. 9 of 37 thin melanomas (24%) were XIAP positive. In contrast, 21 of 30 (73%) thick melanomas were XIAP positive, including 3 of 4 ulcerated melanomas that were strongly positive. Over a follow‐up period ranging from 6 months to 6 years, 23 melanomas metastasized (22 thick, 1 thin). In total, XIAP was immunohistochemically detected in 17 of 23 metastases (74%). Metastasis occurred in 1 of 9 XIAP‐positive thin melanomas; 0 of 28 XIAP‐negative thin melanomas; 17 of 22 XIAP‐positive thick melanomas, and 5 of 8 XIAP‐negative thick melanomas (63%).

Conclusions:  XIAP is immunohistochemically detectable nearly three times more frequently in thick compared with thin melanomas. These results suggest that XIAP elevation may be correlated with increasing melanoma thickness and tumor progression.
A case of cutaneous symplastic leiomyoma – a rare variant of cutaneous pilar leiomyoma
Authors: Usmani Naila , Merchant W , Yung A
Published: October 2007

We describe the case of a cutaneous symplastic leiomyoma in a 37‐year‐old woman who presented with a 4‐year history of a painful slow growing lesion on the left upper arm. The lesion was excised and subjected to histological examination. A poorly circumscribed lesion was seen in the dermis composed of spindle shaped cells with marked nuclear pleomorphism. No mitotic figures or necrosis were seen. The cells stained strongly positive with desmin and smooth muscle actin, and negative with S100, melan A, MNF116 a mouse monoclonal antibody to cytokeratin and CK5/6. The diagnosis was felt to be in keeping with a cutaneous symplastic leiomyoma, a rarely reported variant of the pilar leiomyoma. Histologically, it shows features similar to the symplastic variant of uterine leiomyoma with cytological atypia, nuclear pleomorphism and minimal mitotic activity. Although the long‐term outlook is probably benign, the presence of cytological atypia and mitoses in any spindle cell tumor is generally a concerning feature and warrants long‐term follow up.
Lipophilic and hydrophilic moisturizers show different actions on human skin as revealed by cryo scanning electron microscopy
Authors: Caussin Julia , Groenink H. W. Wouter , Graaff Anko M. de , Gooris Gert S. , Wiechers Johann W. , Van Aelst Adriaan C. , Bouwstra Joke A.
Published: October 2007

Abstract:  To study the mode of action of moisturizers on human skin, hydrophilic moisturizers in water and neat lipophilic moisturizers were applied on excised skin for 24 h at 32°C. Samples of the treated skin were subsequently visualized in a cryoscanning electron microscope. The stratum corneum (SC) appeared as a region of swollen corneocytes (the swollen region) sandwiched between two layers of relatively dry corneocytes (the upper and lower non‐swelling regions respectively). Lipophilic moisturizers increased the water content of the SC, whereas hydrophilic moisturizers can also reduce the water content of the SC. When focusing on the effect of the moisturizers on the three different regions, it was observed that cells in the swelling region are most sensitive to the application of the moisturizers and that the change in SC thickness is most influenced by the change in the thickness of the swelling region. Summarizing, SC cells are not equally sensitive to moisturizer application: centrally located corneocytes are more sensitive than corneocytes in the upper and the lowest regions of the SC.
L‐Carnitine–L‐tartrate promotes human hair growth in vitro
Authors: Foitzik Kerstin , Hoting Edo , Förster Thomas , Pertile Paolo , Paus Ralf
Published: October 2007

Abstract:  The trimethylated amino acid l‐carnitine plays a key role in the intramitochondrial transport of fatty acids for β‐oxidation and thus serves important functions in energy metabolism. Here, we have tested the hypothesis that l‐carnitine, a frequently employed dietary supplement, may also stimulate hair growth by increasing energy supply to the massively proliferating and energy‐consuming anagen hair matrix. Hair follicles (HFs) in the anagen VI stage of the hair cycle were cultured in the presence of 0.5–50 μm of l‐carnitine–l‐tartrate (CT) for 9 days. At day 9, HFs treated with 5 μm or 0.5 μm of CT showed a moderate, but significant stimulation of hair shaft elongation compared with vehicle‐treated controls (P < 0.05). Also, CT prolonged the duration of anagen VI, down regulated apoptosis (as measured by TUNEL assay) and up regulated proliferation (as measured by Ki67 immunohistology) of hair matrix keratinocytes (P < 0.5). By immunohistology, intrafollicular immunoreactivity for TGFβ2, a key catagen‐promoting growth factor, in the dermal papilla and TGF‐β II receptor protein in the outer root sheath and dermal papilla was down regulated. As shown by caspase activity assay, caspase 3 and 7, which are known to initiate apoptosis, are down regulated at day 2 and day 4 after treatment of HFs with CT compared with vehicle‐treated control indicating that CT has an immediate protective effect on HFs to undergo programmed cell death. Our findings suggest that l‐carnitine stimulates human scalp hair growth by up regulation of proliferation and down regulation of apoptosis in follicular keratinocytes in vitro. They further encourage one to explore topical and nutraceutical administration of l‐carnitine as a well‐tolerated, relatively safe adjuvant treatment in the management of androgenetic alopecia and other forms of hair loss.
Effect of myristyl nicotinate on retinoic acid therapy for facial photodamage
Authors: Jacobson Myron K. , Kim Hyuntae , Coyle W. Russell , Kim Moonsun , Coyle Donna L. , Rizer Ronald L. , Jacobson Elaine L.
Published: October 2007

Abstract:  Based on the hypothesis that skin barrier impairment is a contributor to side‐effects associated with retinoic acid therapy, a double‐blind, placebo‐controlled pilot study examined the combined use of retinoic acid with myristyl nicotinate (MN), a lipophilic derivative of niacin that enhances skin barrier function, in female subjects with mild to moderate facial photodamage. The study involved a 1‐month run‐in period with placebo or MN prior to initiation of retinoic acid therapy for 3 months. Analysis of skin biopsies revealed that retinoic acid therapy resulted in stratum corneum thinning of approximately 25% (P = 0.006 versus baseline) that was ameliorated by MN use (P < 0.005). Therapy resulted in an increased rate of transepidermal water loss (TEWL) of approximately 45% (P = 0.001 versus baseline) and use of MN protected against the increase in TEWL with the strongest protection provided by prior use of MN (P = 0.056 versus placebo). MN use reduced the incidence of side‐effects of the therapy and again prior use provided the greatest reduction of side‐effects. Subjects showed statistically significant clinical improvement (P < 0.05 versus baseline) during the study. MN use did not interfere with any clinical improvement parameters and improved effects on temple laxity (P = 0.01 versus placebo). Analysis of changes in epidermal thickness, Ki67‐positive cells and intensity of loricrin staining demonstrated that MN either improved or did not interfere with retinoic acid efficacy. These results show that prior and concurrent use of MN can mitigate barrier impairment and improve the tolerability of retinoic acid therapy for facial photodamage without interfering with efficacy.
Substance P receptor antagonist reverses intestinal pathophysiological alterations occurring in a novel ex‐vivo model of Cryptosporidium parvum infection of intestinal tissues derived from SIV‐infected macaques
Authors: Garza A. , Lackner A. , Aye P. , D’Souza M. , Martin P. , Borda J. , Tweardy D.J. , Weinstock J. , Griffiths J. , Robinson P.
Published: October 2007

Background  Cryptosporidium infection leads to life‐threatening diarrhea in AIDS patients. Pathogenesis of cryptosporidiosis is due to intestinal physiological alterations. We devised an ex‐vivo model using ex‐vivo Cryptosporidium parvum infection of jejunal tissues derived from SIV‐infected macaques and studied the role of substance P (SP) in the pathogenesis of cryptosporidiosis.

Methods  We measured jejunal SP protein levels using ELISA, and electrophysiological alterations using the Ussing chamber technique in an ex vivo model of Cryptosporidium infection. Paraformaldehyde‐fixed jejunum from SIV‐infected macaques with and without naturally occurring cryptosporidiosis was studied for SP protein expression by immunohistochemistry and fluorescence deconvolution microscopy.

Results  Ex‐vivo Cryptosporidium‐infected tissues and tissues from SIV‐infected macaques with naturally occurring cryptosporidiosis demonstrated elevated SP protein levels compared with tissues from SIV‐infected animals without ex‐vivo C. parvum infection or tissues from SIV‐infected animals that have no evidence of cryptosporidiosis. In our ex‐vivo model of Cryptosporidium infection, we demonstrated pathophysiological alterations that were blocked by SP‐receptor antagonist treatment.

Conclusions  These studies suggest that SP‐receptor antagonists could prove useful for treatment of AIDS‐related cryptosporidiosis.
Melatonin reduces the neuronal loss, downregulation of dopamine transporter, and upregulation of D2 receptor in rotenone‐induced parkinsonian rats
Authors: Lin Chun‐Hung , Huang Jui‐Yen , Ching Cheng‐Hsin , Chuang Jih‐Ing
Published: October 2007

Abstract:  Parkinson’s disease (PD) is a movement disorder resulting from nigrostriatal dopaminergic neurodegeneration. The impairment of mitochondrial function and dopamine synaptic transmission are involved in the pathogenesis of PD. Two mitochondrial inhibitors, 1‐methyl‐4‐phenylpyridine (MPP+) and rotenone, have been used to induce dopaminergic neuronal death both in in vitro and in vivo models of PD. Because the uptake of MPP+ is mediated by the dopamine transporter (DAT), we used a cell‐permeable rotenone‐induced PD model to investigate the role of DAT and dopamine D2 receptor (D2R) on dopaminergic neuronal loss. Rotenone subcutaneously infused for 14 days induced PD symptoms in rats, as indicated by reduced spontaneous locomotor activity (hypokinesis), loss of tyrosine hydroxylase (TH, a marker enzyme for dopamine neurons) immunoreactivity in the substantia nigra and striatum, obvious α‐synuclein accumulation, downregulated DAT protein expression, and upregulated D2R expression. Interestingly, rotenone also caused significant noradrenergic neuronal loss in the locus coeruleus. Melatonin, an antioxidant, prevented nigrostriatal neurodegeneration and α‐synuclein aggregation without affecting the rotenone‐induced weight loss and hypokinesis. However, rotenone‐induced hypokinesis was markedly reversed by the DAT antagonist nomifensine and body weight loss was attenuated by the D2R antagonist sulpiride. In addition, both antagonists significantly prevented the reduction of striatal TH or DAT immunoreactivity but not the loss of nigral TH‐ and DAT‐immunopositive neurons. These results suggested that oxidative stress and DAT downregulation are involved in the rotenone‐induced pathogenesis of nigrostriatal dopaminergic neurodegeneration, whereas D2R upregulation may simply represent a compensatory response.
Biofilm inhibition and antimicrobial activity of a dentifrice containing salivary substitutes
Authors: Hatti S , Ravindra S , Satpathy A , Kulkarni RD , Parande MV
Published: October 2007

Abstract:  Background/aims:  A healthy mouth harbours the continuous combined action of a salivary defence system with that of a salivary peroxidase system, containing lactoferrin, lysozyme, immunoglobulin and growth factors. This system maintains neutral pH and creates an oral environment where harmful bacteria are inhibited, thus preventing the formation of biofilms. The objective of this clinico‐microbiological trial was to evaluate the anti‐plaque effect of a dentifrice containing salivary substitutes, compared with a placebo‐control dentifrice and to assess the effect of dentifrice on oral bacterial count.

Methods:  The design was a randomized controlled, double‐blind, parallel study comparing a placebo‐dentifrice to a dentifrice formulation containing salivary substitutes. Toothpaste slurry rinses were used over a 96‐h period by 20 volunteers who refrained from all other oral hygiene procedures. Commercially available fluoride toothpaste was used as control. Plaque was scored and unstimulated salivary samples were collected at day 0 and after 4 days. A microbiological analysis was carried out for the salivary samples. Data were analyzed by using Student’s t‐tests.

Results:  There was a statistically significant mean difference in plaque scores after using test paste (1.19 + 0.31) in comparison with those using placebo toothpaste (1.95 + 0.33). The difference between mean increase in colony forming units for the test and the placebo group was (25.2 + 8) × 105 and (17.5 + 6.01) × 105, respectively, which was statistically significant.

Conclusions:  The findings of the study support the hypothesis that toothpaste containing salivary substitutes prevents dental biofilm formation and exhibits antimicrobial property when compared with a placebo dentifrice.
Assessing the oral health of school‐age children and the current school‐based dental screening programme in Freiburg (Germany)
Authors: Sagheri D , Hahn P , Hellwig E
Published: October 2007

Abstract:  Germany has a three‐tiered system of education at secondary school level, divided into the school types ‘Hauptschule’, Realschule’ and ‘Gymnasium’. All students receive, when aged 6–12 years, a uniform annual dental examination and oral health education programme.

Objectives:  The aim of this cross‐sectional study was to report on the dental caries levels of school‐age children stratified into these three different school types at secondary school level to enable oral healthcare personnel to administer a focused, school‐based dental screening and education programme according to patients’ needs rather than a uniform dental examination.

Methods:  A representative, random sample of 12‐year‐old school children in Freiburg (Germany) was examined and dental caries was recorded using WHO criteria.

Results:  A total of 322 12‐year‐old children participated. The mean DMFT was 0.69. An examination of the distribution of the DMFT score revealed that its distribution is positively skewed. For this reason, this study provides summary analyses based on medians and a non‐parametric rank sum test. The non‐parametric Kruskal‐Wallis H‐test showed a highly significant difference between median scores across the different school types (P‐value = 0.004). The significance was a result of the ‘Gymnasium’ distribution of DMFT scores which differed markedly from the other two school types.

Conclusions:  The finding of the present study suggests that it may be useful to stratify the school dental screening and education programme according to school type and to prioritize children who attend ‘Realschule’ and ‘Hauptschule’. This shift should systematically target children with the greatest need for dental care.