bluuebunny/crossref_metadata_2025 huggingface dataset:
Multipotent skin-derived precursors: adult neural crest-related precursors with therapeutic potential
Authors: Fernandes Karl J.L , Toma Jean G , Miller Freda D
Published: February 2007

We previously made the surprising finding that cultures of multipotent precursors can be grown from the dermis of neonatal and adult mammalian skin. These skin-derived precursors (SKPs) display multi-lineage differentiation potential, producing both neural and mesodermal progenyin vitro, and are an apparently novel precursor cell type that is distinct from other known precursors within the skin. In this review, we begin by placing these findings within the context of the rapidly evolving stem cell field. We then describe our recent efforts focused on understanding the developmental biology of SKPs, discussing the idea that SKPs are neural crest-related precursors that (i) migrate into the skin during embryogenesis, (ii) persist within a specific dermal niche, and (iii) play a key role in the normal physiology, and potentially pathology, of the skin. We conclude by highlighting some of the therapeutic implications and unresolved questions raised by these studies.
Evaluation of neural plasticity in adult stem cells
Authors: Ross Jeffrey J , Verfaillie Catherine M
Published: February 2007

The role of stem cells has long been known in reproductive organs and various tissues including the haematopoietic system and skin. During the last decade, stem cells have also been identified in other organs, including the nervous system, both during development and in post-natal life. More recently, evidence has been presented that stem cells thought to be responsible for the generation of mature differentiated cells of one organ, such as haematopoietic stem cells, may have the ability to also differentiate across lineages and contribute to tissues other than haematopoietic cells, including neuronal tissue, suggesting that easily accessible stem cells sources may one day be useful in the therapy of ischaemic (stroke) and also degenerative diseases of the nervous system. Here, we will evaluate the validity of such claims based on a number of criteria we believe need to be fulfilled to definitively conclude that certain stem cells can give rise to functional neural cells that might be suitable for therapy of neural disorders.
C‐Reactive Protein and the Metabolic Syndrome: Useful Addition to the Cardiovascular Risk Profile?
Authors: Szmitko Paul E. , Verma Subodh
Published: February 2007

The inflammatory marker C‐reactive protein has emerged as a powerful independent predictor of cardiovascular disease risk. C‐reactive protein may also be a mediator of inflammatory processes such as atherosclerosis development and progression, and it appears to be useful in identifying patients with, or at risk for developing, diabetes mellitus and the metabolic syndrome. In the clinical practice setting, measurement of C‐reactive protein levels can add information to help guide management decisions in persons who are at intermediate risk based on Framingham risk scores, who have preexisting cardiovascular disease, or who exhibit components of the metabolic syndrome. A large ongoing trial is investigating whether statin therapy will decrease the risk of cardiovascular disease in patients with elevated levels of C‐reactive protein and low‐to‐normal levels of low‐density lipoprotein cholesterol.
The Cardiometabolic Syndrome and Cardiovascular Disease
Authors: Ash‐Bernal Rachel , Peterson Linda R.
Published: February 2007

The cardiometabolic syndrome is a prevalent metabolic disorder. Epidemiologic studies correlate the cardiometabolic syndrome with an increased risk of coronary heart disease, ischemic stroke, cardiovascular mortality, and total mortality. There is also evidence that the cardiometabolic syndrome is a risk factor for abnormalities in myocardial metabolism, cardiac dysfunction, and arrhythmias such as atrial fibrillation. Multiple imaging modalities, both invasive and noninvasive, may help physicians better define the presence or risk of cardiovascular disease in their patients with the cardiometabolic syndrome.
Solubility of major cations and Cu, Zn and Cd in soil extracts of some contaminated agricultural soils near a zinc smelter in Norway: modelling with a multisurface extension of WHAM
Authors: Almås Å. R. , Lofts S. , Mulder J. , Tipping E.
Published: February 2007

Mechanistic modelling offers a means of simulating the speciation and solubility of trace metals in soils. The WHAM/Model VI model has previously been used to simulate pH buffering and Al solubility in acid soils, and metal partitioning in very organic soils, but has not previously been applied to agricultural soils. Here we have extended the WHAM/Model VI framework to include surface complexation to oxides, and cation exchange, and applied it to batch titrations of limed agricultural soils contaminated by emissions of Cd and Zn from a metal smelter. In contrast to previous studies on forest soils, model predictions were most sensitive to the size of the geochemically ‘active’ soil Ca pool. Following optimization of this pool the model reproduced trends in pH and major cations well. Blind predictions of soil metal concentrations (Cu, Zn and Cd), from estimates of the active soil metal concentrations obtained by extraction with 0.22 m HNO3, were mostly very reasonable. Where predicted metal solubility was different, the model could be fitted to the data by optimizing the size of the active metal pool. In some cases the optimized metal pool was unrealistically large, which indicates a possible deficiency in the way the model considers binding activity and competition. Organic matter was the dominant binding phase in these soils. These results support the contention that speciation modelling has great promise in providing a holistic description of ion chemistry in soils for both major and trace elements.
The biomechanics of Cornus canadensis stamens are ideal for catapulting pollen vertically
Authors: WHITAKER D. L. , WEBSTER L. A. , EDWARDS J.
Published: February 2007

Rapid movements in fungi and plants have evolved in different species to facilitate the dispersal of spores and seeds. The mechanisms of action can differ among species, but the effectiveness of these movements has rarely, if ever, been tested. Here we show through a quantitative biomechanical analysis that the stamens of Cornus canadensis L. (bunchberry) are ideal for catapulting pollen vertically at high speeds.

We develop a biomechanical model to describe the explosive launch of pollen from the flowers of bunchberry. The model determines the equation of motion for the stamens based only on the morphology and measurements of the parts of the stamens. To measure the motion of the stamens to compare with our model, we analysed individual frames of a video taken at 10 000 fps.

The thecae of adjacent stamens dehisce in bud so that the stomia face each other, retaining pollen between neighbouring anthers. As the flowers open, pollen is accelerated vertically as long as the thecae remain in contact. Pollen is released only when the anthers move horizontally and separate.

The observed motion of the stamens matches the results from our model through release of the pollen. The model reveals that pollen release (horizontal movement of the anthers) occurs only after the vertical speed is at its maximum. Thus, for this particular catapult mechanism, the morphology of the stamens is optimal for launching light, dry pollen straight upwards at high speed. Pollen launched vertically at high speed both enhances insect pollination by helping to making pollen stick on visiting insects, and also allows for successful wind pollination by propelling pollen into the air column. Seed set by inflorescences in pollinator‐exclosure cages further supports the ability of this flower to use wind as a pollination mechanism.
Effects of feeding different ensiled forages on the productivity and nutrient‐use efficiency of finishing lambs
Authors: Marley C. L. , Fychan R. , Fraser M. D. , Sanderson R. , Jones R.
Published: February 2007

The effects of offering ensiled red clover (Trifolium pratense), lucerne (Medicago sativa), pea (Pisum sativum), kale (Brassica oleracea) and hybrid ryegrass (Lolium hybridicum) on the productivity and nutrient‐use efficiency of lambs were investigated. Forages were cut, wilted for 24 h and ensiled as round bales. A hundred Suffolk‐cross lambs, aged 8 months, were offered grass silage during a 5‐week standardization period and then group‐housed for 14 d and offered ad libitum access to a treatment silage. For the measurement period, lambs were split into four replicate groups of five lambs per treatment. Dry matter intake and live weight were recorded every 7 d over 56 d. The chemical composition of the silages differed for all the variables measured. Lambs offered pea silage had a very low liveweight gain and this treatment was discontinued after 21 d. Lambs offered the other forages had a higher liveweight gain than lambs offered ryegrass silage (P < 0·001). Food conversion and nitrogen‐use efficiency were higher in lambs offered the red clover, lucerne and kale silages compared with those offered ensiled ryegrass (P < 0·001). These findings demonstrate the potential for using ensiled alternative forages rather than ryegrass to increase the productivity and nutrient use efficiency of livestock systems.
Prevalence of four putative periodontopathic bacteria in saliva of a group of Brazilian children with mixed dentition: 1‐year longitudinal study
Authors: SAKAI VIVIEN T. , CAMPOS MARINELE R. , MACHADO MARIA APARECIDA A. M. , LAURIS JOSÉ ROBERTO P. , GREENE ANDREW S. , SANTOS CARLOS F.
Published: February 2007

Aim.  This study aimed at evaluating the prevalence of putative periodontal pathogens (Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Prevotella nigrescens, Treponema denticola) in saliva of children with mixed dentition at two different time points, correlating these findings with a clinical parameter of gingival health.

Design.  Polymerase chain reaction (PCR) detection was used to determine the prevalence of these bacteria in saliva of 64 children in 2003 and 60 children in 2004. Gingival health was assessed by gingival index.

Result.  Sixty‐two (96.9%) and 50 (83.3%) children presented low gingival inflammation, whereas 2 (3.1%) and 10 (16.7%) had moderate scores in 2003 and 2004, respectively. Majority of the children (81.3% in 2003 and 73.3% in 2004) had detectable levels of at least one of the bacteria. The prevalence found was of 4.7% and 1.7% for A. actinomycetemcomitans, 6.3% and 8.3% for P. gingivalis, 23.4% and 48.3% for P. nigrescens (P < 0.05), and 71.9% and 50% for T. denticola (P < 0.05) in 2003 and 2004, respectively. No significant relationship between gingival index and presence of these bacteria and combination of different species was found.

Conclusion.  A high percentage of children harboured at least one of the putative periodontal pathogens in saliva, but presented periodontally healthy conditions.
Medical and surgical treatment of neonatal hemochromatosis: Single center experience
Authors: Heffron Thomas , Pillen Todd , Welch David , Asolati Massimo , Smallwood Gregory , Hagedorn Phil , Fasola Carlos , Solis David , Rodrigues John , DePaolo Jill , Spivey James , Martinez Enrique , Henry Stuart , Romero Rene
Published: February 2007

Abstract:  NH is a rare disorder of iron storage in newborns resulting in rapid liver failure. Outcomes are dismal with 20–30% survival. We report our experience in eight children with NH. Assessment of liver function included admission PT and serum levels of FV and FVII. Medical treatment (antioxidant cocktail) was started in all patients, with chelation therapy in six. Of these six, three survived with medical treatment alone. The other three underwent liver transplant. One died 158 days after transplant to sepsis: two are well more than five yr after transplant. The two neonates who did not receive chelation therapy, died to multi‐organ failure and sepsis. In summary, five children (62.5%) survived long‐term. In the three transplanted, one‐ and five‐yr‐survival was 66%. Older children with compromised synthetic liver function (FVII levels ≤ 15%) required liver replacement for survival. Early referral to a tertiary care center is essential to increase survival of these children with a rare and otherwise fatal disease. Single center experience of children with NH is here presented. Potentials for survival improvement with of medical and surgical treatment are examined.
Tuberculin skin test positivity in pediatric allogeneic BMT recipients and donors in Turkey
Authors: Tavil Betul , Gulhan Bora , Ozcelik Ugur , Cetin Mualla , Tezcan Ilhan , Tuncer Murat , Uckan Duygu
Published: February 2007

Abstract:  The preliminary study was performed to determine the frequency of tuberculin skin test (TST) positivity among 26 patients and their donors screened by TST to investigate whether tuberculin positivity of a recipient or donor influenced the rate of tuberculosis disease, transplant‐related events, and to evaluate the effectiveness of isoniazide (INAH) prophylaxis administered to those with positive TST. The frequency of TST positivity was 23% (n = 6) among recipients and also 23% (n = 6) among donors. Two recipients and five donors with positive TST received INAH prophylaxis for six months. Our use of INAH prophylaxis in transplant patients was very conservative because of the risk of drug interaction. The transplantation procedure was not postponed for either recipient or donor TST positivity. Despite the high frequency of tuberculosis in our country, we have not detected any case of tuberculosis in our center, either among the purified protein derivative‐screened (n = 26) or non‐screened (n = 128) patients except for disseminated tuberculosis infection because of BCG vaccination in two patients with severe combined immunodeficiency. In conclusion, TST positivity in either recipient or donor may not be a contraindication for bone marrow transplantation and the procedure may not be postponed. Pretransplantation TST screening may be needed in countries where tuberculosis is common in the general population.
Renal transplant in children with previous inferior vena cava thrombosis
Authors: Martinez‐Urrutia Maria Jose , Lopez Pereira Pedro , Avila Ramirez Luis , Lobato Romera Roberto , Alonso Melgar Angel , Jaureguizar Monereo Enrique , Tovar Larrucea Juan
Published: February 2007

Abstract:  Our experience with renal transplantation in children with inferior vena cava thrombosis is presented in this study. Of the 238 children who have received renal transplants at our institution, four had IVC thrombosis (discovered during pretransplant evaluation: three patients; found at surgery: one patient). The pretransplant US evaluation diagnosis of IVC thrombosis in three patients was confirmed by transjugular retrograde cavography. There were no signs of hypercoagulability or IVC thrombosis symptoms prior to diagnosis in any patient. The graft was implanted in a left orthotopic position in three patients. Venous drainage was attained to the infrahepatic vena cava or native renal vein after ipsilateral nephrectomy. The renal artery of the graft was anastomosed to the aorta. In one patient, the graft was placed in the left iliac fossa. Patient and graft survival are 100%. Three grafts are functioning normally after a mean follow‐up of 3.7 yr. The graft placed in the iliac fossa has moderate dysfunction due to high pressure venous outflow. Children with IVC thrombosis can be successfully transplanted orthotopically. Candidates with any suspicious‐looking occlusion on ultrasound should be studied by retrograde venography to confirm diagnosis prior to transplantation.
Deep‐sea hydrocarbon seep gastropod Bathynerita naticoidea responds to cues from the habitat‐providing mussel Bathymodiolus childressi
Authors: Dattagupta Sharmishtha , Martin Jonathan , Liao Shu‐min , Carney Robert S. , Fisher Charles R.
Published: February 2007

Bathynerita naticoidea (Gastropoda: Neritidae) is a numerically dominant heterotrophic gastropod found at hydrocarbon seep sites on the upper Louisiana slope of the Gulf of Mexico. Snails of this species are commonly associated with beds of the methanotrophic mussel Bathymodiolus childressi (Bivalvia: Mytilidae), and their population structure mirrors that of the mussels they are found among. Previous studies have shown that these snails feed on bacteria and decomposing periostracum on the B. childressi shell. We predicted that B. naticoidea might be attracted to cues specific to its preferred habitat, such as dissolved methane, mucus from conspecific snails, or metabolites produced by B. childressi mussels. To examine this, we used a flow‐through Y‐maze system to investigate the behavior of B. naticoidea exposed to these potential cues. We found that the nerite is not attracted to methane, but is strongly attracted to seawater conditioned with B. childressi. The attractant appears to be specific to this type of mussel, and is not a soluble cue produced by conspecific snails.
Meiobenthos from an active methane seepage area in the NW Black Sea
Authors: Sergeeva N. G. , Gulin M. B.
Published: February 2007

Meiobenthos densities and higher taxon composition were studied in an active gas seepage area at depths from 182 to 252 m in the submarine Dnieper Canyon located in the northwestern part of the Black Sea. The meiobenthos was represented by Ciliata, Foraminifera, Nematoda, Polychaeta, Bivalvia, Gastropoda, Amphipoda, and Acarina. Also present in the sediment samples were juvenile stages of Copepoda and Cladocera which may be of planktonic origin. Nematoda and Foraminifera were the dominant groups. The abundance of the meiobenthos varied between 2397 and 52,593 ind.·m−2. Maximum densities of Nematoda and Foraminifera were recorded in the upper sediment layer of a permanent H2S zone at depths from 220 to 250 m. This dense concentration of meiobenthos was found in an area where intense methane seeps were covered by methane‐oxidizing microbial mats. Results suggest that methane and its microbial oxidation products are the factors responsible for the presence of a highly sulfidic and biologically productive zone characterized by specially adapted benthic groups. At the same time, an inverse correlation was found between meiofauna densities and methane concentrations in the uppermost sediment layers. The hypothesis is that the concentration of Nematoda and Foraminifera within the areas enriched with methane is an ecological compromise between the food requirements of these organisms and their adaptations to the toxic H2S.
CTLA‐4 gene promoter and exon 1 polymorphisms in Iranian patients with gastric and colorectal cancers
Authors: Hadinia Abolghasem , Hossieni Seyed Vahid , Erfani Nasrollah , Saberi‐Firozi Mehdi , Fattahi Mohammad Javad , Ghaderi Abbas
Published: February 2007

Background and Aim:  Cytotoxic T‐lymphocyte antigen‐4 (CTLA‐4) is a potent immunoregulatory molecule that suppresses antitumor response by down‐regulating T‐cell activation. Effects of several polymorphisms in CTLA‐4 on CTLA‐4 expression and function have been previously documented. The aim of this study was to investigate the putative effect of CTLA‐4 polymorphisms on susceptibility to gastric and colorectal cancers in an Iranian population.

Methods:  A total of 155 patients (109 with colorectal cancer and 46 with gastric cancer) and 190 age‐ and sex‐matched healthy controls were evaluated. Genotyping of −1722T/C, −1661A/G, and +49A/G were performed by PCR restriction fragment length polymorphism methods and of −318C/T by a PCR amplification refractory mutation system technique.

Results:  No statistically significant differences were found in the genotype distribution and allele frequencies among patients and controls. Haplotype analysis demonstrated that the TACG haplotype (−1722T, −1661A, −318C, +49G) frequency was significant increased in patients with colorectal cancer (P = 0.009) and gastric cancer (P = 0.006) in comparison to the control group. In contrast, the TACA haplotype frequency was significantly decreased in patients with colorectal cancer (P = 0.02) and not significantly decreased in patients with gastric cancer (P = 0.13) compared to the control group.

Conclusion:  A positive association between CTLA‐4 TACG haplotype and gastric and colorectal cancers was found in an Iranian population. A protective role for TACA haplotype is postulated.
Feasibility and cost‐effectiveness of using magnification chromoendoscopy and pepsinogen serum levels for the follow‐up of patients with atrophic chronic gastritis and intestinal metaplasia
Authors: Dinis‐Ribeiro Mário , Da Costa‐Pereira Altamiro , Lopes Carlos , Moreira‐Dias Luís
Published: February 2007

Background:  The follow‐up of patients with atrophic chronic gastritis or intestinal metaplasia may lead to early diagnosis of gastric cancer. However, to‐date no cost‐effective model has been proposed. Improved endoscopic examination using magnification chromoendoscopy together with non‐invasive functional assessment with pepsinogen serum levels are accurate in the diagnosis of intestinal metaplasia (extension) and minute dysplastic lesions. The aim of this study was to assess the feasibility and cost‐effectiveness of a follow‐up model for patients with atrophic chronic gastritis and intestinal metaplasia based on gastric mucosal status using magnification chromoendoscopy and pepsinogen.

Methods:  A cohort of patients with lesions as severe as atrophic chronic gastritis were followed‐up according to a standardized protocol using magnification chromoendoscopy with methylene blue and measurement of serum pepsinogen I and II levels. A single node decision tree and Markov chain modeling were used to define cost‐effectiveness of this follow‐up model versus its absence. Transition rates were considered time‐independent and calculated using primary data following cohort data analysis. Costs, quality of life and survival were estimated based on published data and extensive sensitivity analysis was performed.

Results:  A total of 100 patients were successfully followed‐up over 3 years. Seven cases of dysplasia were diagnosed during follow‐up, all among patients with incomplete intestinal metaplasia at baseline, six of whom had extensive (pepsinogen I to II ratio <3) incomplete intestinal metaplasia. For those individuals with atrophic chronic gastritis or complete intestinal metaplasia, a yearly measurement of pepsinogen levels or an endoscopic examination on a 3‐yearly basis would cost €455 per quality‐adjusted life year (QALY) gain. Endoscopic examination and pepsinogen serum level measurement on a yearly basis would cost €1868 per QALY for patients with extensive intestinal metaplasia.

Conclusions:  The follow‐up of patients with atrophic chronic gastritis or intestinal metaplasia is both feasible and cost‐effective if improved accurate endoscopic examination of gastric mucosa together with non‐invasive assessment of gastric mucosal status are used to identify individuals at high‐risk for development of gastric cancer.
Baseline and time‐averaged fluid removal affect technique survival in peritoneal dialysis in a non‐linear fashion
Authors: WIGGINS KATHRYN J , RUMPSFELD MARKUS , HAWLEY CARMEL M , O'SHEA AMANDA , ISBEL NICOLE M , CAMPBELL SCOTT B , JOHNSON DAVID W
Published: February 2007

Aim:  The longevity of peritoneal dialysis (PD) is limited by technique failure and patient mortality. The authors assessed the influence of baseline and time‐averaged fluid removal on patient, technique and death‐censored technique survival.

Methods:  Peritoneal and total fluid removal was measured 1 month after commencing PD, then 6 monthly, in 225 incident patients (mean age 55.3 ± 15.8 years, 52% male). A Cox proportional hazards model regression analysis was performed to identify variables independently predictive of technique and patient survival.

Results:  Seventy (31.9%) patients were transferred to haemodialysis and 39 (17.63%) died. Technique survival was greatest in the middle tertile of baseline total fluid removal (mean survival time 3.5 vs 2.5 and 2.2 years for the lower and upper tertiles, respectively, log rank 6.5, P = 0.039). The middle tertile of both baseline and time‐averaged total fluid removal were significant predictors of PD survival (adjusted hazard ratio (HR) 0.476, 95% CI 0.286–0.795, P = 0.005 relative to the upper tertile and HR 0.573, 95% CI 0.350–0.939, P = 0.027 for baseline and time‐averaged, respectively). Other significant variables on multivariate analysis were body mass index (HR 1.044 per kg/m2, 95% CI 1.005–1.084, P = 0.028), creatinine (HR 0.999 per μmol, 95% CI 0.998–1.000, P = 0.048) and residual Kt/V (HR 0.418, 95% CI 0.233–0.747, P = 0.003). Patient survival was not affected by fluid removal.

Conclusion:  Patients with moderate total fluid removal both at baseline and throughout their PD career have improved technique survival. Attention should be paid to optimizing total fluid removal.
Dose of epoetin alfa used in haemodialysis patients when switching from subcutaneous to intravenous administration
Authors: PUSSELL BRUCE A , WALKER ROWAN
Published: February 2007

Aim:  To determine whether there is a change in the dose of epoetin alfa when switching from subcutaneous (SC) to intravenous (IV) administration in Australian haemodialysis patients.

Methods:  Validated data from 2214 haemodialysis patients at 16 Australian hospitals who switched from SC to IV administration of epoetin alfa from January 2002 to September 2003 were extracted from the Renal Anaemia Management database provided by Janssen‐Cilag. Of these patients, 806 had dosing data for at least 1 month before switch through to 6 months post switch (6 month cohort).

Results:  In the 6 month cohort, the mean dose was 10 776 IU/week (95% CI: 10 235, 11 317) at switch compared with 12 008 IU/week (95% CI: 11 447, 12 569) 6 months post switch, an increase in a dose of 1232 IU/week (95% CI: 868, 1596). The mean haemoglobin levels at switch were 11.55 g/dL (95% CI: 11.45, 11.66) compared with 11.59 g/dL (95% CI: 11.49, 11.68) 6 months after switch. Centre and dosing frequency of epoetin alfa before switch were determinants of increased dose.

Conclusion:  Changing from SC to IV administration of epoetin alfa resulted in an 11% increase in mean dose to maintain haemoglobin levels in Australian haemodialysis patients.
Evaluating the use of a scanning laser‐derived oedema index to grade diabetic retinopathy and maculopathy
Authors: Styles Caroline J , Park Serena JK , McGhee Charles NJ , Gamble Greg , Donaldson Mark L
Published: February 2007

Abstract

Purpose:   To evaluate the Heidelburg Retina Tomograph II (HRTII) retinal module as a tool for grading severity of retinopathy in a diabetic retinal screening and treatment service.

Methods:   Seventy‐seven consecutive patients with type 2 diabetes underwent scanning laser tomography using the HRTII. Scan data were analysed using the proprietary macular module software and oedema indices calculated for each of nine topographic macular zones. Two consultant ophthalmologists, masked to the result of the HRTII scans, graded each subject for severity of retinopathy and presence of macular oedema. The oedema indices were analysed statistically to determine whether these correlated with severity of retinopathy and presence of macular oedema.

Results:   There is an increased oedema index in severe non‐proliferative diabetic retinopathy in the outer temporal zone compared with lesser grades of diabetic retinopathy (P = 0.001). In patients with clinically detectable macular oedema, the oedema index from the 500‐µm‐diameter central zone was significantly higher than those without (P = 0.03).

Conclusion:   The scanning laser‐derived oedema index differentiated between moderate and severe non‐proliferative diabetic retinopathy in this series and detected diabetic macular oedema. Further development of this technology may provide an important tool to supplement retinal photographic surveillance in eye clinics overwhelmed by an increasing prevalence of type 2 diabetes.
Langerhans cell histiocytosis of the optic chiasm
Authors: Gangwani Vinod , Walker Mark , El‐Defrawy Hany , Nicoll James AR , Reck Anne , Pathmanathan Thillainathan
Published: February 2007

Abstract

Langerhans cell histiocytosis (LCH) is a rare disease with clonal proliferation of dendritic histiocytes forming a pseudotumoral growth. LCH occurs most frequently in infancy or early childhood. It can present either as a localized self‐limiting form or as a diffuse form with multisystem involvement. Herein an unusual case of LCH involving the optic chiasm is presented. To the authors’ knowledge, this is the first reported case of LCH presenting with visual disturbance. The clinical, radiological and histopathological findings are discussed.
Employees’ Well‐being in Greater China: The Direct and Moderating Effects of General Self‐efficacy
Authors: Siu Oi‐ling , Lu Chang‐qin , Spector Paul E.
Published: February 2007

This study investigated the direct and moderating effect of general self‐efficacy on the relationship between stressors and well‐being in Chinese societies. Survey data were collected from 386 and 306 employees in Hong Kong and Beijing, respectively. The results consistently showed that general self‐efficacy was positively related to mental well‐being and physical well‐being. A series of hierarchical regressions revealed that general self‐efficacy moderated the relationship between stressors and mental well‐being, yet did not moderate the relationship between stressors and physical well‐being. Results verified that general self‐efficacy plays an important role in employees’ well‐being in the collectivist society of China.

Cette recherche porte sur l’effet direct et régulateur de l’auto‐efficience générale sur la relation entre les facteurs de stress et le bien‐être dans les sociétés chinoises. Les données d’enquête ont été obtenues auprès de 386 salariés de Hong‐Kong et 306 de Pékin. Les résultats montrent régulièrement que l’auto‐efficience générale est positivement corrélée avec le bien‐être physique et mental. Une succession de régressions hiérarchiques a révélé que l’auto‐efficience générale régulait la relation entre les facteurs de stress et le bien‐être mental, mais pas celle entre les facteurs de stress et le bien‐être physique. Les résultats vérifient l’hypothèse selon laquelle l’auto‐efficience générale joue un rôle important pour le bien‐être des salariés dans la société collectiviste chinoise.
Characteristics of incidental prostatic adenocarcinoma in contemporary radical cystoprostatectomy specimens
Authors: Winkler Mathias H. , Livni Naomi , Mannion Ethna M. , Hrouda David , Christmas Timothy
Published: February 2007

OBJECTIVES

To investigate the relationship between prostate‐specific antigen (PSA) level and tumour volume for incidental adenocarcinoma of the prostate found in cystoprostatectomy (CP) specimens, and to analyse the incidence of clinically significant prostate cancers in CP specimens and the biochemical recurrence of incidental prostate cancers on short‐term follow up.

PATIENTS AND METHODS

Complete data from 97 of 105 prostates from CP specimens were available. Prostates were thoroughly analysed and sectioned at 2 mm intervals. PSA levels and the findings at digital rectal examination before surgery were obtained prospectively. None of the patients had any evidence of prostate cancer before CP.

RESULTS

Incidental prostate cancer was detected in 58 of 97 (60%) of the CP specimens; of these, 31 (53%) were significant according to the definition of Stamey et al. There was a weak correlation between tumour volume and PSA level, weighted solely by the four larger‐volume cancers. The median PSA level for patients with and without prostate cancer was not significantly different (3.1 vs 1.1 ng/mL, P = 0.06). The follow‐up of the 35 patients alive with prostate cancer showed four PSA recurrences (PSA >0.02 ng/mL) with one distant metastasis after a median follow‐up of 3 years. None of the patients with insignificant tumours developed biochemical recurrence.

CONCLUSIONS

The weak correlation between PSA level and tumour volume in these patients supports the argument that PSA is largely produced by benign prostatic hyperplasia and is therefore a poor screening tool for asymptomatic healthy men. Most incidental prostate cancers in CP specimens are significant, contrary to previous analyses, but have little practical importance in terms of oncological outcome.
JOHN HARRIS' ARGUMENT FOR A DUTY TO RESEARCH
Authors: BRASSINGTON IAIN
Published: February 2007

John Harris suggests that participation in or support for research, particularly medical research, is a moral duty. One kind of defence of this position rests on an appeal to the past, and produces two arguments. The first of these arguments is that it is unfair to accept the benefits of research without contributing something back in the form of support for, or participation in, research. A second argument is that we have a social duty to maintain those practices and institutions that sustain us, such as those which contribute to medical knowledge. This argument is related to the first, but it does not rely so heavily on fairness. Another kind of defence of the duty to research rests on an appeal to the future benefits of research: research is an effective way to discharge a duty to rescue others from serious illness or death, therefore we have a duty to research. I suggest that all three of Harris' lines fail to provide a compelling duty to research and spell out why. Moreover, not only do the lines of argument fail in their own terms: in combination, they turn out to be antagonistic to the very position that Harris wants to defend. While it is not my intention here to deny that there might be a duty to research, I claim that Harris' argument for the existence of such a duty is not the best way to establish it.
ISLAMIC MEDICAL ETHICS: A PRIMER
Authors: PADELA AASIM I.
Published: February 2007

Modern medical practice is becoming increasingly pluralistic and diverse. Hence, cultural competency and awareness are given more focus in physician training seminars and within medical school curricula. A renewed interest in describing the varied ethical constructs of specific populations has taken place within medical literature. This paper aims to provide an overview of Islamic Medical Ethics. Beginning with a definition of Islamic Medical Ethics, the reader will be introduced to the scope of Islamic Medical Ethics literature, from that aimed at developing moral character to writings grounded in Islamic law. In the latter form, there is an attempt to derive an Islamic perspective on bioethical issues such as abortion, gender relations within the patient‐doctor relationship, end‐of‐life care and euthanasia. It is hoped that the insights gained will aid both clinicians and ethicists to better understand the Islamic paradigm of medical ethics and thereby positively affect patient care.
Sentinel lymph node biopsy in patients with thick (= 4 mm) melanoma: a single‐centre experience
Authors: Cecchi R , Buralli L , Innocenti S , Seghieri G , De Gaudio C
Published: February 2007

Background and objective  Lymphatic mapping/sentinel lymph node biopsy (LM/SLNB) have become routine techniques for staging the regional lymph nodes in early stage melanoma, yet their role in the management of thick (= 4 mm) melanoma is debated. The aim of the present study is to review our experience with LM/SLNB in a series of patients with thick primary melanoma, to evaluate its utility in this melanoma subset.

Patients and methods  Thirty patients (18 men and 12 women; mean age 70.6 years; median 75 years) with thick primary melanoma underwent LM/SLNB, using both radioisotope and blue dye. The statistical tests were performed by using SAS software for Windows, version 8.2.

Results  The primary tumour sites were head/neck (n = 5; 16.6%), trunk (n = 10; 33.3%), and extremities (n = 15; 50%). Tumour thickness ranged from 4 to 17 mm (mean 5.14 mm; median 4.5 mm). Ulceration was observed in 23 (76.6%) tumours. Eleven patients (36.6%) had at least a positive sentinel lymph node (SLN). The mean follow‐up was 27.3 months (median 26 months; range 5–63 months). Patients without SLN metastases had a 5‐year disease‐free survival rate of 78.9%, vs. 18.2% for patients with SLN metastases (P = 0.0121 by log rank test). The 5‐year overall survival rate for patients without SLN metastases was 89.5%, whereas patients with SLN metastases had a 5‐year overall survival rate of 36.4% (P = 0.0272 by log rank test).

Conclusion  Our retrospective analysis indicates that the SLN status is predictive of recurrence and survival in patients with thick melanoma, and LM/SLNB should be routinely performed in this subset of melanoma patients.
Gold: an old drug still working in refractory pemphigus
Authors: Iranzo P , Alsina MaM , Martínez‐De Pablo I , Segura S , Mascaró JM , Herrero C
Published: February 2007

Background  The mainstay of treatment for pemphigus is systemic corticosteroids. Different adjuvants have been used to reduce side‐effects of long‐term corticotherapy. Gold is an anti‐inflammatory drug used in autoimmune diseases, whose use has waned with the advent of new immunosuppressive agents.

Objective  To study the outcome of the use of intramuscular gold treatment of pemphigus vulgaris refractory to previous therapies.

Methods  Thirteen patients with pemphigus vulgaris who had failed to respond to several prior therapies were treated with aurothiomalate, as a steroid‐sparing agent. Patients were monitored to assess disease activity and gold toxicity.

Results  Seven patients achieved complete remission. Four patients were able to taper prednisone doses, although pemphigus flared when prednisone was discontinued or reduced. Toxicity was observed in the other two patients.

Conclusions  In 53.4% of the patients, the use of chrysotherapy resulted in the complete clearing of the disease, discontinuation of all systemic therapies and induced a long‐term clinical remission. Prednisone doses were able to be reduced in the remaining 46.6%. Any side‐effects were reversible with drug discontinuation. Gold therapy showed efficacy as a secondary line treatment in refractory pemphigus vulgaris.
Temporal Variability of Atrial Fibrillation in Pacemaker Recipients for Bradycardia: Implications for Crossover Designed Trials, Study Sample Size, and Identification of Responder Patients by Means of Arrhythmia Burden
Authors: BOTTO GIOVANNI LUCA , SANTINI MASSIMO , PADELETTI LUIGI , BORIANI GIUSEPPE , LUZZI GIANNI , ZOLEZZI FRANCESCO , ORAZI SERAFINO , PROCLEMER ALESSANDRO , CHIARANDÀ GIACOMO , FAVALE STEFANO , SOLIMENE FRANCESCO , LUZI MARIO , VIMERCATI MARCO , DeSANTO TIZIANA , GRAMMATICO ANDREA
Published: February 2007

Background: Most clinical trials that have tested pacing therapies to prevent and treat atrial tachyarrhythmias (AT) have chosen endpoints such as AT frequency or burden (defined as percentage of time a patient is in AT), but failed to show unequivocal evidence of a clinical impact.

Aim: The aim of our multicenter prospective observational study was to measure the variability of AT burden and estimate its impact on study outcomes.

Methods and Results: Two hundred and fifty patients indicated for permanent pacing and suffering from AT (age 71 ± 9 years; 47.2% male) received a dual‐chamber pacemaker. AT burden was measured in two consecutive, 2‐month observation periods; the Monte Carlo method was then applied to simulate findings of a crossover design study. We simulated several models of therapy impact, each model being characterized by the percentage of responder patients and the percentage reduction in AT burden. To show a significant impact of AT therapies in a sample of 250 patients in whom 100, 75, or 50% would be theoretical responders to therapies, AT burden reduction should be at least 27, 32, or 57%, respectively. Temporal fluctuations in AT burden were so high that about 60% of patients would falsely appear as responders or nonresponders in a crossover study, regardless of AT burden reduction.

Conclusions: In patients paced for bradycardia and suffering from AT, high intrapatient variability in AT burden was measured. Various models of therapy impact showed that, in crossover trials of AT therapies, time‐related fluctuations in AT burden negatively impact on sample sizes and impair the ability to identify patients as responders or nonresponders.
Breast Cancer and Scleroderma
Authors: Alon Scope , Siegal Sadetzki , Yechezkel Sidi , Aviv Barzilai , Henry Trau , Bela Kaufman , Rafael Catane , Michael Ehrenfeld
Published: February 2007

Introduction. Epidemiologic studies have shown that patients with scleroderma have an increased risk of cancer.

Methods. The authors report eight cases and retrospectively review the published data on the possible association between breast cancer and scleroderma of the cutaneous and systemic forms. The records of all patients with scleroderma and breast cancer who were hospitalized during 1980–2002 in the Chaim Sheba Medical Center were surveyed. A literature search for breast cancer and scleroderma was performed.

Results. The clinical data of 65 women patients with breast cancer and scleroderma, eight of whom were hospitalized in the Chaim Sheba Medical Center and 57 who were reported in the literature, are summarized. In 29 patients (44%), scleroderma appeared before or simultaneously with the diagnosis of breast cancer. While a higher frequency of systemic scleroderma was described in this group, a higher rate of cutaneous scleroderma appeared in the group where scleroderma followed breast cancer diagnosis ( p<0.001).

Conclusions. Large‐scale case‐control studies are needed to substantiate the possible association between scleroderma—both cutaneous and systemic—and breast cancer.
Male Pattern Androgenetic Alopecia
Authors: Virendra N. Sehgal , Ashok K. Aggarwal , Govind Srivastava , Punit Rajput
Published: February 2007

Androgenic alopecia is a common physiologic disorder that is induced by androgens in genetically predisposed persons. It is described by dermatologists as a disorder of perception. Its original classification in men was made by Hamilton in 1951 and modified by Norwood in 1975. Ludwig's classification of androgenic alopecia in women was made in 1977. More study on this subject is needed with respect to searching for a medication to promote hair growth.
Nucleation of Perovskite Nanocrystals in a Levitating Liquid
Authors: Tangeman Jean A. , Phillips Brian L. , Hart Robert
Published: February 2007

Containerless liquid‐phase processing methods were used to synthesize two glasses, both containing alumina (A), yttria (Y), and lanthana (L), and one containing ∼20 mole% silica (S) as well. In both materials, denoted AYL and AYLS, alumina is the dominant component (>50 mole%), and the lanthana:yttria ratio is ∼2:1. A variety of experimental techniques, e.g. X‐ray diffraction, high‐field 27Al magic angle spinning‐nuclear magnetic resonance (MAS‐NMR), differential scanning calorimetry, and neutron diffraction, were used to analyze both the structure of the amorphous phases resulting from liquid‐phase processing and subsequent thermal treatments, and the thermodynamic properties of the as‐made and heat‐treated materials. The results of the experiments on these glasses and liquids have elucidated the nature of the transitions occurring between the glass transition and crystalline regimes, and have enabled the synthesis of a novel class of alumina‐based nanomaterials.
Structural Disorder and Intracrystalline Microtexture of α′H‐(Ba0.24Ca0.76)2SiO4
Authors: Fukuda Koichiro , Hasegawa Hajime , Iwata Tomoyuki , Hashimoto Shinobu , Inoue Koji
Published: February 2007

The structural disorder and twin microtexture of (Ba0.24Ca0.76)2SiO4crystal were investigated by X‐ray powder diffraction, precession method, and optical microscopy. The crystal at 298 K was orthorhombic (space groupPnma,Z=4) witha=0.70490(5) nm,b=0.55399(4) nm,c=0.95532(7) nm, andV=0.37306(4) nm3. The crystal structure was satisfactorily described by a split‐atom model, involving the positional disorder of Ba/Ca and O atoms across the (010) mirror plane. The crystal was found to be isostructural with α′H‐Ca2SiO4, thus regarded as the stabilized α′Hphase. The crystal grain was composed of orthorhombic domains in three different orientations. The unit cells within each domain were related to one another by the threefold pseudo‐symmetry axis lost during the α‐to‐α′Htransition. Each domain was most probably made up of sub‐domains of the two mirror‐related structural configurations withP21/nsymmetry.
Epiphyseal Union Sequencing: Aiding in the Recognition and Sorting of Commingled Remains*
Authors: Schaefer Maureen C. , Black Sue M.
Published: February 2007

ABSTRACT: The presence of accessory osseous material within a seemingly single individual assemblage has the potential to result in misidentification of the remains. Detection of nonrelated material relies on the anthropologist being able to recognize incongruities among the elements. Inconsistencies in developmental status provide evidence to suggest that commingling may have occurred. Analyzing the sequence in which the various epiphyses unite can help to identify outlying elements that do not match the predicted developmental pattern of the remaining skeleton, thus indicating that the element may not belong to that individual. This paper considers the sequence in which 21 various epiphyses of the body unite to serve as a reference for identifying incongruent fusing patterns within a commingled assemblage. Two hundred and fifty‐eight male individuals of Bosniak (Bosnian Muslim) descent between the ages of 14 and 30 years were included for analysis. Sequence order was determined for both “beginning” and “complete” union by comparing the fusing status of each epiphysis with each of the other 21 epiphyses. Considering both sequence patterns provides a wider spectrum of evidence from which to recognize incongruities than either sequence pattern could provide in isolation. Variations to the majority sequence pattern were also included to ensure that skeletons displaying less popular but acceptable sequence patterns would not be mistakenly considered as two individuals when using this research as a reference. Although substantial variation in the order in which epiphyses initiate and complete union was discovered within the sample, most epiphyseal relationships did not display any variable patterns. These “unvaried” relationships will be most useful in recognizing the presence of incongruent material if the pattern within an assemblage does not conform to the pattern documented in this study. Figures demonstrating the two sequence patterns are provided for easy application in the field.
Perivascular Fat: Innocent Bystander or Active Player in Vascular Disease?
Authors: Stern Naftali , Marcus Yonit
Published: February 2007

Although nearly all arteries are surrounded by perivascular fat, its role in vascular function and disease is clearly understudied. At least one type of perivascular fat, epicardial adipose tissue, appears to be related to both weight and age and tends to express proatherogenic/proinflammatory products in subjects with cardiovascular disease. Perivascular fat may evolve from primordial cells in the adventitia or from circulating precursors migrating through the arterial wall. Once deposited periarterially, adipose tissue may release locally a large number of products, which potentially interact with the arterial wall. Additionally, the authors propose that perivascular fat, per se, may attract circulating monocytes through the release of chemokines such as monocyte chemoattractant protein‐1. Some of the macrophages traversing the arterial wall en route to the perivascular fat may be redirected and eventually populate the arterial wall itself, thereby enhancing vascular inflammatory processes and accelerating atherosclerosis.