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Selected AbstractsConstruction of an antibody microarray based on agarose-coated slidesELECTROPHORESIS, Issue 3 2007Lin-Li Lv Abstract The antibody microarray, a high-throughput multiplex immunoassay method, has become a significant tool for quantitative proteomics studies. We describe here the strategies for optimizing the condition of antibody microarray building based on agarose-coated slides. In this study, modified glass slides were robotically printed with capture antibodies against monocyte chemoattractant protein 1 (MCP-1), then dilutions of the cytokine were applied to the arrays, and the protein was detected with biotin-labeled antibody coupled with Cy3-conjugated streptavidin. Thus a protein profiling microarray based on sandwich immunoassay has been established. Various factors in the production of antibody microarrays were analyzed: the capture antibody concentrations, shelf life of the postprinting slides, blocking buffers, and reproducibility of the system. A calibration curve with a correlation coefficient of 0.9995 was established which suggested that the matrix can retain arrayed proteins in near-quantitative fashion. The results revealed high signal uniformity and reproducibility with regard to intra-array (1.3%) and the interarray (8.7%) variation at the capture antibody concentration of 125,µg/mL. Besides, the printed arrays could be stored for at least two months without any apparent change of the performance parameters. [source] Assessment of high density of onsite wastewater treatment systems on a shallow groundwater coastal aquifer using PCAENVIRONMETRICS, Issue 3 2005Steven Carroll Abstract Onsite wastewater treatment systems are common throughout the world, including Australia, with approximately 17% of the Australian population relying on these systems to treat and ultimately dispose of wastewater. Systems which are properly sited, designed and managed are an effective way of providing the necessary treatment of wastewater. However, incidence of onsite system failure is common, and this is further compounded in areas where high densities of systems are established. The density of systems is not appropriately assessed in the siting and design stage. Various factors, such as site and soil characteristics and climate, can influence the treatment efficiency, and this is more critical in high density areas. Principal component analysis was used for assessing chemical and microbiological data from shallow groundwater below a high density of onsite treatment systems. The results of this study confirmed that high system densities can significantly impact shallow groundwater systems. Additionally, changes in spatial and climatic conditions, as well as the type of onsite system, can also influence the quality of groundwater. Copyright © 2004 John Wiley & Sons, Ltd. [source] Renal phosphate handling in human , what can we learn from hereditary hypophosphataemias?EUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 6 2010Stefan Amatschek Eur J Clin Invest 2010; 40 (6): 552,560 Abstract Background, Renal reabsorption of inorganic phosphate is critical for the maintenance of phosphate homeostasis. The sodium dependent phosphate cotransporters NaPi-IIa and NaPi-IIc have been identified to fulfill this task at the brush border membrane of proximal tubule cells. Various factors including dietary phosphate intake, parathyroid hormone, or the so called phosphatonins such as FGF23 have been shown to regulate activity of these transporters. Design, This review seeks to give an update on our current knowledge about regulatory mechanisms involved in human renal phosphate reabsorption. Results, Recently, an increasing number of genes have been identified that are directly associated with inherited phosphate wasting disorders (Klotho, PHEX, DMP1 and NHERF1). Several of these genes are predominantly expressed by osteocytes and osteoclasts in the bone suggesting indispensable signalling pathways between kidneys and the skeleton. Conclusion, In this review, the affected gene products in these inherited hypophosphataemias and their contribution to phosphate homeostasis are discussed. [source] From small-scale habitat loopholes to decadal cycles: a habitat-based hypothesis explaining fluctuation in pelagic fish populations off PeruFISH AND FISHERIES, Issue 4 2004Arnaud Bertrand Abstract The Peru-Humboldt Current system (HCS) supports the world's largest pelagic fisheries. Among the world's eastern boundary current systems, it is the most exposed to high climatic stress and is directly affected by El Niño and La Niña events. In this volatile ecosystem, fish have been led to develop adaptive strategies in space and time. In this paper, we attempt to understand the mechanisms underlying such strategies, focusing on the El Niño 1997,98 in Peru from which an extensive set of hydrographic, capture and acoustic survey data are available. An integrated analysis of the data is crucial, as each has substantial shortcomings individually; for example, both catch data and acoustic surveys may easily lead to wrong conclusions. Existing hypotheses on anchovy and sardine alternations lead us to a ,habitat-based' synthetic hypothesis. Using our data, an integrated approach evaluated how fish responded to habitat variation, and determined the consequences in terms of fish-population variability. Various factors occurring at a range of different spatio-temporal scales were considered: interdecadal regime (warm ,El Viejo'/cool ,La Vieja' decadal scale); strength and the duration of the El Niño Southern Oscillation event (interannual scale); population condition before the event (interannual scale); fishing pressure and other predation (annual scale); changes in reproductive behaviour (intra-annual scale); presence of local upwelling (local scale). During El Niño 1997,98, anchovy was able to exploit a small-scale temporal and spatial ,loophole' inside the general unfavourable conditions. Moreover, sardine did not do better than anchovy during this El Niño and was not able to take advantage of the ,loophole' opened by this short-term event. Our results question the traditional view that El Niño is bad for anchovy and good for sardine. [source] Reconciling traditional inland fisheries management and sustainability in industrialized countries, with emphasis on EuropeFISH AND FISHERIES, Issue 4 2002Robert Arlinghaus Abstract In northern industrialized countries, the inland fisheries sector has long been dominated by recreational fisheries, which normally exploit fish for leisure or subsistence and provide many (poorly investigated) benefits to society. Various factors constrain the development and existence of inland fisheries, such as local user conflicts, low social priority and inadequate research and funding. In many cases, however, degradation of the environment and loss of aquatic habitat are the predominant concerns for the sustainability of inland fisheries. The need for concerted effort to prevent and reduce environmental degradation, as well as conservation of freshwater fish and fisheries as renewable common pool resources or entities in their own right is the greatest challenge facing sustainable development of inland waters. In inland fisheries management, the declining quality of the aquatic environment coupled with long-term inadequate and often inappropriate fisheries management has led to an emphasis on enhancement practices, such as stocking, to mitigate anthropogenic stress. However, this is not always the most appropriate management approach. Therefore, there is an urgent need to alter many traditional inland fisheries management practices and systems to focus on sustainable development. This paper reviews the literature regarding the inputs needed for sustainability of inland fisheries in industrialized countries. To understand better the problems facing sustainable inland fisheries management, the inland fisheries environment, its benefits, negative impacts and constraints, as well as historical management, paradigms, trends and current practices are described. Major philosophical shifts, challenges and promising integrated management approaches are envisaged in a holistic framework. The following are considered key elements for sustainable development of inland fisheries: communication, information dissemination, education, institutional restructuring, marketing outreach, management plans, decision analysis, socioeconomic evaluation and research into the human dimension, in addition to traditional biological and ecological sciences. If these inputs are integrated with traditional fisheries management practices, the prospects for sustainability in the inland fisheries will be enhanced. [source] Characteristics of skin aging in Korean men and womenINTERNATIONAL JOURNAL OF COSMETIC SCIENCE, Issue 1 2005J. H. Chung Introduction Korea is located between Japan and Mainland China. The people of these three countries have similar appearances and it is difficult to differentiate between them. Although the population of Asia is more than half of the total population of the Earth, the inherent characteristics of Asian skin have not been well investigated. Commercial markets for cosmetics and drugs for photoaged skin are rapidly expanding in many Asian countries. Therefore, many investigators in the field of dermatology and cosmetology have become interested in brown Asian skin. Clinical characteristics of skin aging and photoaging in Asians Skin aging can be divided into two basic processes: intrinsic aging and photoaging [1]. Intrinsic aging is characterized by smooth, dry, pale, and finely wrinkled skin, whereas photoaging, which indicates premature skin aging in chronically photodamaged skin, is characterized by severe wrinkling and irregular pigmentation. The pattern of wrinkling in Asians seems to differ from that in Caucasians. Asians have coarser, thicker and deep wrinkles, particularly in the forehead, perioral and Crow's foot areas. In contrast, Caucasians usually have relatively fine cheek and Crow's foot wrinkles. The reasons for these differences are not known and need further investigation. There are racial, ethnic and genetic differences, and differences of skin structure and function, between the brown skin of Asians and the white skin of Caucasians. As Asian skin is more pigmented, acute and chronic cutaneous responses to UV irradiation differ from those in white skin. Many people believe, based on clinical impressions, that the main process of photoaging in Asians involves pigmentary changes, rather than wrinkling. However, no study has been performed to confirm this belief. Risk factors for skin wrinkles and their relative risks in Korean skin [2] Various factors such as age, sun-exposure, and smoking are known to be important risk factors for wrinkles. However, the relative risks of each factor on wrinkles in the brown skin of Asians have not been investigated, and they could differ from those in Caucasians. An evaluation system for skin wrinkling is necessary for Asian skin [3]. Thus, we developed an eight-point photographic scale for assessing wrinkles in both Korean genders [2]. This scale can probably be applied to the populations of other Asian countries, at least to the Japanese and Chinese. The pattern of wrinkles in both genders appears to be similar. Age Age is an important risk factor for wrinkling in Asians, as in Caucasians. Korean subjects in their 60s showed a 12-fold increased risk of wrinkling, while subjects in their 70s have a 56-fold increased risk compared with young age group. UV light It is well known that the UV component in sunlight can cause and accelerate photoaging. The pigmented skin of Asian may better protect skin from acute and chronic UV damage. However, we found a strong association between sun-exposure and the development of wrinkling in Koreans. It was found that sun exposure of more than 5 h per day was associated with a 4.8-fold increased risk in wrinkling versus less than 2 h of sun-exposure in Koreans. Estrogen deficiency Korean females have more wrinkles than men, after controlling for age, sun exposure, and smoking, it was found that they have a 3.6-fold increased risk of developing wrinkles than their male counterparts [2]. It has also been reported, that the relative risk for wrinkling in women is higher than in men as for in white Caucasians [4]. The reason why women show more wrinkles remains to be determined. It is possible that a reduction in skin collagen because of estrogen deficiency in postmenopausal woman may aggravate wrinkling severity. Korean women with more than 10 years since menopause showed a 3.9-fold higher risk of wrinkling than the women 5 years of beyond menopause [5]. We demonstrated that women with a history of HRT have a significantly lower risk, more specifically, one fifth of the risk of facial wrinkling relative to those who had no history of HRT. Interestingly, we found that wrinkle severity significantly increased with an increasing number of full term pregnancies. The relative risk for severe wrinkling is increased by approximately 1.8-fold per full term pregnancy. Smoking It is known that smoking causes skin wrinkling in Caucasians, and that it plays no role in Blacks [6, 7]. Koreans with have a smoking history of more than 30 pack years showed a more than 2.8-fold increased risk of wrinkles [2]. The relative risks of wrinkles associated with a 30,50 pack-years history of smoking were 2.8- and 5.5-fold, respectively. Dyspigmentation in Asian skin To follow pigmentary changes, six photographic standards for both genders were developed for Korean skin, to produce a 6-point scale [2, 8]. Hyperpigmented spots, mostly lentigines, were prominent among women, while seborrheic keratosis tended to be more prominent in men. Seborrheic keratosis in Korean men Seborrheic keratoses (SKs) are benign cutaneous tumors. They have diverse clinical and histopathological appearances and are very common in the elderly (over 50 years old). The etiology of SKs is not well understood, although patients with a great number of lesionsshow a familial trait with an autosomal dominant pattern, and human papilloma virus has been suggested as possible cause because of verrucous appearance of the lesions. Exposure to sunlight has been suggested to be a risk factor for SKs. However, there is still some debate in terms of the role of sunlight. Recently, we have investigated the clinical characteristics of SKs and relationship between SKs and sunlight exposure in Korean males [9]. The prevalence of SKs in Koreans increases with age; it rose from 78.9% at 40 years, to 93.9% at 50 years and 98.7% in those over 60 years. Exposed areas, i.e. the face, neck and dorsum of the hands, demonstrate a significant increase in the prevalence of SKs by decade, whereas partly exposed areas, although SKs tended to increase in prevalence with age, this trend was not significant. When the estimated body surface area (BSA) is taken into account, the number of SKs on both the face and dorsum of the hands (0.51 ± 0.08 per 1% BSA) was over-represented compared with the trunk. SKs were also concentrated on the neck (0.38 ± 0.07 per 1% BSA) and in the V-area (0.47 ± 0.09 per 1% BSA). Outer forearms also showed 3-fold more SKs per unit area than neighboring arms and inner forearms, which are classified as partly exposed area (0.09 ± 0.02, 0.03 ± 0.01, respectively). The total area covered by SKs on exposed area also became significantly larger with aging than on intermittently exposed areas. These results indicate that exposure to sunlight might be related to SK growth. Our results indicated that excessive sun exposure is an independent risk factor of SKs. After controlling for age, smoking, and skin type, subjects with a sun exposure history of more than 6 hours per day showed a 2.28-fold increased risk of having severe SKs (n , 6) compared with those exposed for less that 3 h per day. These findings indicated that sun-exposure may play an important role in SK development. In summary, SKs are very common in Korean males and represent one of the major pigmentary problems. SKs concentrate on exposed skin, especially on the face and dorsum of the hands. Both age and lifetime cumulative sunlight exposure are important contributing factors and may work in a synergistic manner. Conclusion Many people tend to believe that wrinkles are not a prominent feature of Asian photoaged skin, and that dyspigmentation is a major manifestation in Asian skin. Contrary to this impression, wrinkling is also a major problem in the photoaged skin of Asians, and Korean people showing severe pigmentary changes usually tend to have severe wrinkles. In conclusion, the wrinkling patterns and pigmentary changes of photoaged skin in East Asians differ from those of Caucasians, and the relative risks of aggravating factors may be different from those of Caucasian skin. References 1.,Gilchrest, B.A. Skin aging and photoaging: an overview. J. Am. Acad. Dermatol. 21, 610,613 (1989). 2.,Chung, J.H. et al. Cutaneous photodamage in Koreans: influence of sex, sun exposure, smoking, and skin color. Arch. Dermatol. 137, 1043,1051 (2001). 3.,Griffiths, C.E. et al. A photonumeric scale for the assessment of cutaneous photodamage. Arch. Dermatol. 128, 347,351 (1992). 4.,Ernster, V.L. et al. Facial wrinkling in men and women, by smoking status. Am. J. Public Health. 85, 78,82 (1995). 5.,Youn, C.S. et al. Effect of pregnancy and menopause on facial wrinkling in women. Acta Derm. Venereol. 83, 419,424 (2003). 6.,Kadunce, D.P. et al. Cigarette smoking: risk factor for premature facial wrinkling. Ann. Intern. Med. 114, 840,844 (1991). 7.,Allen, H.B., Johnson, B.L. and Diamond, S.M. Smoker's wrinkles? JAMA. 225, 1067,1069 (1973). 8.,Chung, J.H. Photoaging in Asians. Photodermatol. Photoimmunol. Photomed. 19, 109,121 (2003). 9.,Kwon, O.S. et al. Seborrheic keratosis in the Korean males: causative role of sunlight. Photodermatol. Photoimmunol. Photomed. 19, 73,80 (2003). [source] Mechanism of calcium oxalate renal stone formation and renal tubular cell injuryINTERNATIONAL JOURNAL OF UROLOGY, Issue 2 2008Masao Tsujihata Abstract: Formation of calcium oxalate stones tends to increase with age and begins from the attachment of a crystal formed in the cavity of renal tubules to the surface of renal tubular epithelial cells. Though most of the crystals formed in the cavity of renal tubules are discharged as is in the urine, in healthy people, crystals that attach to the surface of renal tubular epithelial cells are thought to be digested by macrophages and/or lysosomes inside of cells. However, in individuals with hyperoxaluria or crystal urine, renal tubular cells are injured and crystals easily become attached to them. Various factors are thought to be involved in renal tubular cell injury. Crystals attached to the surface of renal tubular cells are taken into the cells (crystal,cell interaction). And then the crystal and crystal aggregates grow, and finally a stone is formed. [source] Percutaneous absorption and exposure assessment of pesticidesJOURNAL OF APPLIED TOXICOLOGY, Issue 2 2010Mai A. Ngo Abstract Dermal exposure to a diverse range of chemicals may result from various uses. In order to assess exposure and estimate potential risks, accurate quantitative data on absorption are required. Various factors will influence the final results and interpretations of studies designed to assess the ability of compounds to penetrate the skin. This overview will discuss skin penetration by pesticides, emphasizing key parameters to be considered from the perspective of exposure assessment. Copyright © 2009 John Wiley & Sons, Ltd. [source] Factors that predict cecal insertion time during sedated colonoscopy: The role of waist circumferenceJOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 2 2008Yu-Hsi Hsieh Abstract Background and Aim:, Various factors have been closely linked to the cecal insertion time. These factors include age, sex, body mass index, quality of bowel preparation, doctor's technique, a history of prior hysterectomy, diverticulosis, and constipation. Waist circumference is better than body mass index in assessing abdominal obesity and therefore may be better than body mass index in predicting cecal insertion time. The aim of this study was to evaluate the factors influencing cecal insertion time and the impact of waist circumference. Methods:, This prospective study was conducted between August 2004 and June 2005 in Buddhist Dalin Tzu Chi General Hospital. Asymptomatic patients admitted to our physical check-up department were enrolled. A single endoscopist performed all colonoscopies under sedation with a single-handed method. Age, sex, body mass index, waist circumference, history of hysterectomy, constipation, bowel cleansing status, and diverticulosis were analyzed. Results:, A total of 1022 patients were enrolled. Among them, 996 (97.5%) completed the colonoscopic examinations (472 men and 524 women). The mean ± SD insertion time was 307 ± 166 s for men and 403 ± 195 s for women (P < 0.01). Female sex, poor bowel preparation, smaller waist circumference, lower body mass index and older age were associated with longer insertion time. Waist circumference was better than body mass index in predicting cecal insertion time. Conclusion:, Female sex, poor bowel preparation, smaller waist circumference, lower body mass index and older age were associated with a longer insertion time. Waist circumference was a better predictor than body mass index in assessing cecal insertion time. [source] Polymeric systems for amorphous ,9 -tetrahydrocannabinol produced by a hot-melt method.JOURNAL OF PHARMACEUTICAL SCIENCES, Issue 11 2006Part II: Effect of oxidation mechanisms, chemical interactions on stability Abstract The objectives of the present research investigations were to (i) elucidate the mechanism for the oxidative degradation of ,9 -tetrahydrocannabinol (THC) in polymer matrix systems prepared by a hot-melt fabrication procedure, and (ii) study the potential for controlling these mechanisms to reduce the degradation of THC in solid dosage formulations. Various factors considered and applied included drug-excipient compatibility, use of antioxidants, cross-linking in polymeric matrices, microenvironment pH, and moisture effect. Instability of THC in polyethylene oxide (PEO)-vitamin E succinate (VES) patches was determined to be due to chemical interaction between the drug and the vitamin as well as with the atmospheric oxygen. Of the different classes and mechanisms of antioxidants studied, quenching of oxygen by reducing agents, namely, ascorbic acid was the most effective in stabilizing THC in PEO-VES matrices. Only 5.8% of the drug degraded in the ascorbic acid-containing patch as compared to the control (31.6%) after 2 months of storage at 40°C. This coupled with the cross-linking extent and adjustment of the pH microenvironment, which seemed to have an impact on the THC degradation, might be effectively utilized towards stabilization of the drug in these polymeric matrices and other pharmaceutical dosage forms. These studies are relevant to the development of a stable transmucosal matrix system for the therapeutic delivery of amorphous THC. © 2006 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 95:2473,2485, 2006 [source] Evaluation of different protein sources for aquafeeds by an optimised pH-stat systemJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 7 2002Francisco J Alarcón Abstract This paper presents the results of some experiments oriented to optimise and standardise the measurement of protein hydrolysis by fish proteases using the pH-stat technique. Various factors affecting the degree of hydrolysis (DH) were considered (autohydrolysis of the protein sources, type of enzymes utilised, substrate/enzyme ratio and effect of inhibitors). The crude extracts obtained from fish digestive tissues showed their suitability for the determination of protein hydrolysis, rendering better results than those obtained using mixtures of commercial enzymes. DH values for a given protein were greatly affected by the substrate/enzyme ratio, since small modifications in protein concentration resulted in significant variations in DH. Protease inhibitors present in various plant protein sources produced a reduction in DH values. © 2002 Society of Chemical Industry [source] Integrating gender into a basic medical curriculumMEDICAL EDUCATION, Issue 11 2005P Verdonk Introduction, In 1998, gaps were found to exist in the basic medical curriculum of the Radboud University Nijmegen Medical Centre regarding health-related gender differences in terms of biological, psychological and social factors. After screening the curriculum for language, content and context, adjustments aimed at incorporating gender issues were proposed. The aim of this study was to evaluate those adjustments, as well as to investigate whether gender had been successfully incorporated into the basic medical curriculum, and to identify the factors that played a role in this. Methods, The education material of 9 curricular blocks was re-evaluated and interviews were held with block co-ordinators. Results, Since the beginning of the project, gender has increasingly been brought to the attention of the students. Various factors have played a role: concrete and directly executable content-oriented proposals for adjustment; adequate translation of gender differences into actual patient care; motivated block co-ordinators; the presence of a ,trigger person' in the faculty; incorporation into the existing education programme; the involvement of block co-ordinators in decision making, and the provision of practical support. Discussion, Integrating gender into the basic medical curriculum has been largely successful. Block co-ordinators' personal recognition of the importance of gender in patient care greatly facilitated implementation. The evaluation stimulated the forming of new ideas. It is recommended that these factors and those mentioned above should be taken into consideration when integrating gender into other faculties. [source] The acceptability of 360-degree judgements as a method of assessing undergraduate medical students' personal and professional behavioursMEDICAL EDUCATION, Issue 1 2005Charlotte Rees Introduction, Medical students' personal and professional behaviours have been assessed poorly in medical schools. No research exists exploring the acceptability of 360-degree judgements as a method of assessing such behaviours. This study aims to explore students' and assessors' views and experiences of 360-degree judgements. Methods, Eighteen students and 12 assessors participated in 4 focus group discussions in spring 2003. Discussions were audio-taped and transcribed verbatim and the transcripts were theme analysed independently by 2 analysts. Results, Although 360-degree judgements were felt to drive students' behaviour positively, they were also thought to influence learning and behaviour adversely. Various factors were thought to influence assessors' abilities to make good quality judgements, such as situational factors like the length of time spent with students, characteristics relating to the assessment criteria and characteristics of the assessor, such as apathy. Discussion, Additional research using qualitative and quantitative methods is needed to explore these issues further. [source] Combined Vitamin C and E Supplementation Retards Early Progression of Arteriosclerosis in Heart Transplant PatientsNUTRITION REVIEWS, Issue 11 2002Article first published online: 16 SEP 200 The development of arteriosclerosis is the limiting factor for the long-term survival and the major cause of mortality in patients with heart transplants. Various factors, including oxidative stress, contribute to the progression of the disease. In a recent clinical trial using the intravascular ultrasound technique, which detects the early stages of disease development, supplementation with vitamins C and E retarded the progression of coronary arteriosclerosis during the early stage following cardiac transplantation. [source] Forest Rehabilitation and Its Implication for Forest Transition TheoryBIOTROPICA, Issue 1 2010Wil De Jong ABSTRACT Forest transition theory bases its predictions of forest recovery in temperate regions primarily on macro-economic factors. In tropical countries, it is important to understand additional complex processes underlying forest recovery. Forest rehabilitation,meaning efforts to restore tree cover,is an important contributor to forest recovery in many tropical regions. Forest rehabilitation itself is subject to multiple factors that influence its scale, effectiveness and outcomes. This paper reviews forest rehabilitation in six countries,Brazil, China, Indonesia, Peru, Philippines and Vietnam. The cases reviewed suggest that globally, forest rehabilitation efforts can be understood in four time periods, or eras, each with distinct approaches to forest rehabilitation and outcomes. Various factors that influence forest rehabilitation outcomes evolved during these eras. Current outcomes of forest rehabilitation can only be adequately predicted if the historical processes influencing forest rehabilitation are understood. The paper suggests that forest transition in the tropics needs to be analyzed not only in terms of macro-economic factors, but also in terms of the factors that influence forest rehabilitation outcomes as well as other processes that affect forest cover increase. [source] Alterations in the epidermal,dermal melanin axis and factor XIIIa melanophages in senile lentigo and ageing skinBRITISH JOURNAL OF DERMATOLOGY, Issue 1 2006N. Ünver Summary Background, Senile lentigo (SL) is a pigmentation disorder that occurs predominantly on the dorsa of the hands, the forearms and the face; its incidence increases with age. Histological hallmarks of SL lesions are hyperpigmentation of the epidermis and elongation of the epidermal rete ridges. Various factors such as , -melanocyte-stimulating hormone, endothelin-1 or stem cell factor are involved in the onset and maintenance of the increased pigmentation. Alterations of the dermal compartment have not yet been analysed in detail in SL. Objectives, To study the occurrence and distribution of melanin in the dermis from SL and aged skin, biopsies from 12 subjects were morphologically analysed by light and electron microscopy in comparison with unaffected skin. Methods, Punch biopsies of SL and adjacent skin from 12 male or female volunteers aged 52,81 years were prepared for light and electron microscopy and samples were analysed by morphological, morphometric, histochemical and immunohistochemical methods. Results, The epidermis from SL revealed morphological features such as hyperpigmentation of basal keratinocytes and the formation of elongated rete ridges. S100+ melanocytes in the stratum basale were not markedly increased, indicating that the hyperpigmentation is predominantly due to changes in melanin synthesis, distribution or turnover. Quantification of epidermal cells expressing the proliferation marker Ki67 did not show an increase of this parameter in SL, indicating that at least in the established lesion cell proliferation is not enhanced. We further focused on the dermal compartment and observed granulated cells which were more abundant in SL. Electron microscopic and histochemical analysis revealed that the granulation of these cells is based on melanosomes, mostly present in large melanosomal complexes. Immunohistochemistry using antibodies to CD68 and factor XIIIa (FXIIIa) showed these melanophages to be predominantly FXIIIa+ dermal dendrocytes, which were about six times more abundant than CD68+ macrophages. Conclusions, In SL an increased number of melanophages was found compared with unaffected skin from the same subject. These melanophages were identified as FXIIIa+ dermal dendrocytes. Possible functional consequences of the massive melanin uptake by dermal dendrocytes are discussed. [source] Getting to goal in complex patientsCLINICAL CARDIOLOGY, Issue S2 2003C. Venkata Abstract Traditionally, the term complex hypertension has been applied to patients who have clinical evidence of target organ damage. However, this definition can be expanded to include many hypertensive patients who either present without manifest disease but harbor silent concomitant organ damage, or belong to a high-risk group and are likely to develop such damage. Thus, the number of patients who deserve special consideration as complex patients is considerable. Various factors may contribute toward classifying a patient as having complex hypertension. These include severe hypertension; concomitant conditions such as diabetes, chronic renal insufficiency, coronary artery disease, or congestive heart failure; and high-risk populations such as the elderly and African Americans. Recent evidence demonstrates that aggressive goal blood pressure (BP)-lowering therapy is the key toward halting the progression of vascular disease. Although the choice of initial therapy seems less important than achieving goal B P, the drug selected must impart efficacy, organ protection, and tolerability. Combination therapy consisting of calcium-channel blockers and angiotensin-converting enzyme inhibitors seems to achieve these desirable effects. Several clinical trials have demonstrated these agents to have favorable effects on BP and organ protection even in complex hypertension, particularly when used in combination. [source] Descriptive epidemiology of anotia and microtia, Hawaii, 1986,2002CONGENITAL ANOMALIES, Issue 4 2005Mathias B. Forrester ABSTRACT The objective of this investigation was to describe the epidemiology of anotia and microtia with respect to various factors. The cases studied were all infants and fetuses with anotia or microtia identified by a population-based birth defects registry in Hawaii. The anotia and microtia rates were determined for selected factors and comparisons made among the subgroups by calculating the rate ratio (RR) and 95% confidence interval (CI). A total of 120 cases were identified, for a rate of 3.79 per 10 000 live births. The anotia and microtia rate increased during 1986,2002, although the trend was not significant (P = 0.715). Of 49 specific structural birth defects examined, four were found to be significantly more common in the presence of anotia and microtia. When compared with Caucasians, the anotia and microtia rates were higher among Far East Asians (RR 1.79, 95% CI 0.89,3.68), Pacific Islanders (RR 2.26, 95% CI 1.24,4.32), and Filipinos (RR 2.34, 95% CI 1.23,4.64). The defects were less common among females (RR 0.64, 95% CI 0.43,0.93) and more common with multiple birth (RR 3.72, 95% CI 1.66,7.33), birth weight <,2500 g (RR 3.35, 95% CI 2.04,5.30), and gestational age <38 weeks (RR 2.27, 95% CI 1.49,3.40). In conclusion, the rate for anotia and microtia increased in Hawaii during the study period. The rates for only a few structural birth defects were substantially greater than expected in association with anotia and microtia. Anotia and microtia rates varied significantly according to maternal race/ethnicity, infant sex, plurality, birth weight, and gestational age. [source] A study of primary nucleation of calcium oxalate monohydrate: II.CRYSTAL RESEARCH AND TECHNOLOGY, Issue 7 2004Effect of urinary species Abstract Kidney stones consist of various organic and inorganic compounds. Calcium oxalate monohydrate (COM) is the main inorganic constituent of kidney stones. However, the mechanisms for the formation of calcium oxalate kidney stones are not well understood. In this regard, there are several hypotheses including nucleation, crystal growth and/or aggregation of formed COM crystals. The effect of some urinary species such as oxalate, calcium, citrate, and protein on nucleation and crystallization characteristics of COM is determined by measuring the weight of formed crystals and their size distributions under different chemical conditions, which simulate the urinary environment. Statistical experimental designs are used to determine the interaction effects among various factors. The data clearly show that oxalate and calcium promote nucleation and crystallization of COM. This is attributed to formation of a thermodynamically stable calcium oxalate monohydrate resulting from supersaturation. Citrate, however, inhibits nucleation and further crystal growth. These results are explained on the basis of the high affinity of citrate to combine with calcium to form soluble calcium citrate complexes. Thus, citrate competes with oxalate ion for binding to calcium cations. These conditions decrease the amount of free calcium ions available to form calcium oxalate crystals. In case of protein (mucin), however, the results suggest that no significant effect could be measured of mucin on nucleation and crystal growth. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Childhood trauma in obsessive-compulsive disorder, trichotillomania, and controlsDEPRESSION AND ANXIETY, Issue 2 2002Christine Lochner M.A. Abstract There is relatively little data on the link between childhood trauma and obsessive-compulsive/putative obsessive-compulsive spectrum disorders. The revised Childhood Trauma Questionnaire (CTQ), which assesses physical, emotional, and sexual abuse as well as physical and emotional neglect, was administered to female patients with obsessive-compulsive disorder (OCD; n = 74; age: 36.1 ± 16.3), TTM (n = 36; age: 31.8 ± 12.3), and a group of normal controls (n = 31; age: 21.5 ± 1.0). The findings showed a significantly greater severity of childhood trauma in general, and emotional neglect specifically, in the patient groups compared to the controls. Although various factors may play a role in the etiology of both OCD and trichotillomania (TTM), this study is consistent with some evidence from previous studies suggesting that childhood trauma may play a role in the development of these disorders. Depression and Anxiety 15:66,68, 2002. © 2002 Wiley-Liss, Inc. [source] Statistical Analysis of Surgical Dog-Ear RegressionDERMATOLOGIC SURGERY, Issue 8 2008KYUNG SUK LEE MD BACKGROUND Several methods have been developed to prevent or correct dog-ears. Most of these methods, however, result in prolonged scars and operative times. OBJECTIVE We observed dog-ears without correction to examine the regression of dog-ears with time. METHODS The study was performed on 43 cases of dog-ears in 26 patients. Linear regression analysis was performed to examine the correlation between various factors and the height of the dog-ears (%). We produced a regression equation to allow prediction of the height of the dog-ears (%). In addition, we estimated the initial height of the dog-ears that should be removed during surgery. RESULTS The height of dog-ears regressed with time, and this response was better in younger and female patients. It was predicted that the time taken for a dog-ear to reduce to 50% of its original height was 20.697 days; the median time at which dog-ears completely regressed was 132 days. The odds of regression of dog-ears with an initial height of ,8 mm was 4.667 times greater than that of larger dog-ears. CONCLUSIONS If the height of a dog-ear is ,8 mm, we recommend observation rather than immediate surgical removal. [source] Differentiation inducing factors in Dictyostelium discoideum: A novel low molecular factor functions at an early stage(s) of differentiationDEVELOPMENT GROWTH & DIFFERENTIATION, Issue 9 2009Akiko A. Oohata There are reports that secreted factor(s) are involved in prespore cell differentiation in Dictyostelium discoideum, but the structures and functions of the various factors have not been elucidated. Previously, we described two prespore cell-inducing factors in conditioned medium; one was a glycoprotein named prespore cell-inducing factor (, factor, or PSI-1), and the other, a heat stable dialyzable factor(s). In the present paper, we purified and characterized the most potent prespore cell-inducing activity in dialysates. The factor began to be secreted after the onset of starvation and stopped being secreted once the cells had aggregated, which was earlier than the onset of the , factor gene expression. In addition, unlike , factor, its secretion did not appear to depend on activation of protein kinase A. Interestingly, the purified factor not only induced prespore cell specific genes such as pspA and cotC but also a prestalk-cell specific gene, ecmB in vitro. The purified factor is tentatively designated polyketide-like factor (PLF), because it seems to be a novel polyketide with 208 Da. Half maximal induction of prespore cell was obtained with 26 nmol/L of PLF. We propose that PLF plays a key role in the acquisition of differentiation commitment, before the , factor induces specifically prespore cell differentiation. [source] The rich generally get richer, but there are exceptions: Correlations between species richness of native plant species and alien weeds in MexicoDIVERSITY AND DISTRIBUTIONS, Issue 5-6 2004Francisco J. Espinosa-García ABSTRACT Studies on the resistance of communities to plant invasions at different spatial scales have yielded contradictory results that have been attributed to scale-dependent factors. Some of these studies argue either for or against Elton's notion of biotic resistance against invasions through diversity. We studied the correlation between alien weeds and native species, dividing the latter group into weedy and non-weedy species, integrating various factors that influence diversity into an analysis on the scale of the federal states of Mexico. The resulting multiple-regression models for native and alien weed species are robust (adjusted R2 = 0.87 and R2 = 0.69, respectively) and show a strong partial correlation of the number of weed species (native and alien) with the number of non-weed native species. These results agree with studies showing a positive correlation between the number of native and alien species on larger scales. Both models also include human population density as an important predictor variable, but this is more important for alien weeds (, = 0.62) than for native weeds (, = 0.32). In the regression model for native weed species richness, the non-cultivated (fallow) area (, = 0.24) correlated positively with native weed richness. In the model for alien weed species richness, the native weed species richness was an important variable (, = ,0.51), showing a negative partial correlation (rpart = ,0.4). This result is consistent with Elton's biotic resistance hypothesis, suggesting that biotic resistance is scale independent but that this may be masked by other factors that influence the diversity of both weeds and non-weeds. [source] Prospects for therapeutic vaccination with glatiramer acetate for neurodegenerative diseases such as Alzheimer's diseaseDRUG DEVELOPMENT RESEARCH, Issue 2 2002Michal Schwartz Abstract Neurodegenerative diseases, whatever their primary causes, are characterized by certain common features, one of which is their self-perpetuating nature. The ongoing progression of the disorder is due to the effects of destructive self-compounds, whose presence in the tissues is an outcome of the early phase of the disease and which gradually destroy remaining functional neurons. Studies in our laboratory have led to the recent formulation of a novel concept of protective autoimmunity as the body's mechanism of defense against these destructive self-compounds. This autoimmune response to central nervous system (CNS) insults is mediated by T-cells and presumably operates by activating and regulating local microglia and infiltrating macrophages (inflammatory response) to carry out their function of clearing destructive material from the tissue at risk. We suggest that a well-controlled autoimmunity counteracts and overcomes the destructive effects of the potentially harmful self-compounds, at the cost of some loss of tissue. An additional risk to the individual is the induction of an autoimmune disease, which is likely to occur if the autoimmune response is malfunctioning. An optimal balance of the various factors will lead to an outcome of maximal benefit at minimal cost to the tissue. A procedure for safely boosting the autoimmune response, by vaccination with a weak self-crossreactive antigen such as glatiramer acetate (also known as Cop-1) was found to protect rats from glutamate toxicity, a major mediator of the spread of damage and a well-known causative factor in neurodegenerative disorders. Cop-1, when administered according to a different regimen, is an FDA-approved drug for the treatment of multiple sclerosis. Different formulations of the same drug can therefore be used to treat two extreme manifestations of chronic degenerative diseases of the CNS. Drug Dev. Res. 56:143,149, 2002. © 2002 Wiley-Liss, Inc. [source] Health Status among Emergency Department Patients Approximately One Year after Consecutive Disasters in New York CityACADEMIC EMERGENCY MEDICINE, Issue 10 2005William George Fernandez MD Abstract Objectives: Emergency department (ED) patients with disaster-related experiences may present with vague symptoms not clearly linked to the event. In 2001, two disasters in New York City, the World Trade Center disaster (WTCD) and the subsequent American Airlines Flight 587 crash, presented an opportunity to study long-term consequences of cumulative disaster exposure (CDE) on health-related quality of life (HRQOL) among ED patients. Methods: From July 15 to October 30, 2002, a systematic sample of stable, adult patients from two EDs in New York City were enrolled. Participants completed a self-administered questionnaire. The Short Form 36 (SF-36) was used to assess overall health status. Bivariate analyses were conducted to identify individual correlates of worsening health status. Multivariate regression was performed to identify the association between various factors and overall health status, while controlling for relevant sociodemographic variables. Results: Four hundred seventy-one patients (54.6% female) participated. The participation rate was 73.4%. One hundred sixty-one participants (36%) reported direct, indirect, or occupational exposure to the WTCD; 55 (13.3%) had direct, indirect, or occupational exposure to the plane crash; 33 (8.1%) had both exposures. In separate multivariate models, CDE predicted lower SF-36 scores for general health (p < 0.0096), mental health (p < 0.0033), and bodily pain (p < 0.0046). Conclusions: In the year following mass traumatic events, persons with CDE had lower overall health status than those with one or no disaster exposure. Clinicians should consider the impact that traumatic events have on the overall health status of ED patients in the wake of consecutive disasters. [source] Scale-dependence in species-area relationshipsECOGRAPHY, Issue 6 2005Will R. Turner Species-area relationships (SARs) are among the most studied phenomena in ecology, and are important both to our basic understanding of biodiversity and to improving our ability to conserve it. But despite many advances to date, our knowledge of how various factors contribute to SARs is limited, searches for single causal factors are often inconclusive, and true predictive power remains elusive. We believe that progress in these areas has been impeded by 1) an emphasis on single-factor approaches and thinking of factors underlying SARs as mutually exclusive hypotheses rather than potentially interacting processes, and 2) failure to place SAR-generating factors in a scale-dependent framework. We here review mathematical, ecological, and evolutionary factors contributing to species-area relationships, synthesizing major hypotheses from the literature in a scale-dependent context. We then highlight new research directions and unanswered questions raised by this scale-dependent synthesis. [source] The role of spatial scale and the perception of large-scale species-richness patternsECOLOGY LETTERS, Issue 2 2005Carsten Rahbek Abstract Despite two centuries of exploration, our understanding of factors determining the distribution of life on Earth is in many ways still in its infancy. Much of the disagreement about governing processes of variation in species richness may be the result of differences in our perception of species-richness patterns. Until recently, most studies of large-scale species-richness patterns assumed implicitly that patterns and mechanisms were scale invariant. Illustrated with examples and a quantitative analysis of published data on altitudinal gradients of species richness (n = 204), this review discusses how scale effects (extent and grain size) can influence our perception of patterns and processes. For example, a hump-shaped altitudinal species-richness pattern is the most typical (c. 50%), with a monotonic decreasing pattern (c. 25%) also frequently reported, but the relative distribution of patterns changes readily with spatial grain and extent. If we are to attribute relative impact to various factors influencing species richness and distribution and to decide at which point along a spatial and temporal continuum they act, we should not ask only how results vary as a function of scale but also search for consistent patterns in these scale effects. The review concludes with suggestions of potential routes for future analytical exploration of species-richness patterns. [source] Novel Sensitive Voltammetric Detection of Trace Gallium(III) with Presence of Catechol Using Mercury Film Silver Based ElectrodeELECTROANALYSIS, Issue 16 2009Robert Piech Abstract A new adsorptive stripping voltammetric method for the determination of trace gallium(III) based on the adsorption of gallium(III)-catechol complex on the cyclic renewable mercury film silver based electrode (Hg(Ag)FE) is presented. The effects of various factors such as: preconcentration potential and time, pulse height, step potential and supporting electrolyte composition are optimized. The calibration graph is linear from 2,nM (0.14,,g L,1) to 100,nM (6.97,,g L,1) for a preconcentration time of 30,s, with correlation coefficient of 0.9993. For a Hg(Ag)FE with a surface area of 9.7,mm2 the detection limit for a preconcentration time of 90,s is as low as 7,ng L,1. The repeatability of the method at a concentration level of the analyte as low as 0.05,,g L,1, expressed as RSD is 3.6% (n=5). The proposed method was successfully applied by studying the natural samples and simultaneous recovery of Ga(III) from spiked water and sediment samples. [source] Renewable Copper and Silver Amalgam Film Electrodes of Prolonged Application for the Determination of Elemental Sulfur Using Stripping VoltammetryELECTROANALYSIS, Issue 7 2008Robert Piech Abstract New, renewable copper (Hg(Cu)FE) and silver (Hg(Ag)FE) based amalgam film electrodes applied for the determination of elemental sulfur using differential pulse cathodic stripping voltammetry are presented. With surface areas adjustable from 1 to 12,mm2, both electrodes are characterized by very good surface reproducibility (,2%) and long-term stability (a few thousand measurement cycles). The mechanical refreshing of the amalgam film takes about 1,2 seconds. The effects of various factors such as instrumental parameters and the supporting electrolyte composition were optimized. Interferences from sulfides are easily removed by the addition of acid, and bubbling with argon, for Hg(Ag)FE. In the case of Hg(Cu)FE, sulfides did not interfere. The calibration graph is linear within the studied range from 16,ng L,1 to 4.8,,g L,1 for Hg(Cu)FE, and up to 6.4,,g L,1 for Hg(Ag)FE (tacc=15,s). The correlation coefficients for the two electrodes were at least 0.997. The detection limits for a low concentration of S(0) and tacc=60,s are as low as 14,ng L,1 for Hg(Cu)FE and 4,ng L,1 for Hg(Ag)FE. The proposed method was successfully applied and validated by studying the recovery of S(0) from spiked river water. [source] Mechanisms of Epileptogenesis in Tuberous Sclerosis Complex and Related Malformations of Cortical Development with Abnormal Glioneuronal ProliferationEPILEPSIA, Issue 1 2008Michael Wong Summary Malformations of cortical development (MCDs) are increasingly recognized as causes of medically intractable epilepsy. In order to develop more effective, rational therapies for refractory epilepsy related to MCDs, it is important to achieve a better understanding of the underlying mechanisms of epileptogenesis, but this is complicated by the wide variety of different radiographic, histopathological, and molecular features of these disorders. A subset of MCDs share a number of characteristic cellular and molecular abnormalities due to early defects in neuronal and glial proliferation and differentiation and have a particularly high incidence of epilepsy, suggesting that this category of MCDs with abnormal glioneuronal proliferation may also share a common set of primary mechanisms of epileptogenesis. This review critically analyzes both clinical and basic science evidence for overlapping mechanisms of epileptogenesis in this group of disorders, focusing on tuberous sclerosis complex, focal cortical dysplasia with balloon cells, and gangliogliomas. Specifically, the role of lesional versus perilesional regions, circuit versus cellular/molecular defects, and nonneuronal factors, such as astrocytes, in contributing to epileptogenesis in these MCDs is examined. An improved understanding of these various factors involved in epileptogenesis has direct clinical implications for optimizing current treatments or developing novel therapeutic approaches for epilepsy in these disorders. [source] | ||||||||||||||||||||||||||||||||||||||||||||||||||||