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PubMed2006

The role of brown adipose tissue in human obesity.

It is widely accepted that newborn humans are provided with brown adipose tissue (BAT) and that adult humans lack, or have only a small amount, of it. Therefore the physiological role of BAT in humans is debated. It is quite clear that BAT in rodents has an important role in the prevention and therapy of obesity and diabetes and specific drugs can induce BAT development in adult animals. New concepts regarding the biology of adipose tissues in mammals have been developed during the last years leading to the hope for the development of BAT in human adults as a new challenge for the treatment of obesity and related diseases. These new concepts are basic to understanding the above-proposed therapeutic strategy and are the concept of the adipose organ and the concept of transdifferentiation. In this paper these new concepts will be explained together with a review of available scientific data on human BAT.

Adipocytes, Brown↗
PubMed2005

An analysis of maxillary anterior teeth: facial and dental proportions.

STATEMENT OF PROBLEM: The size and form of the maxillary anterior teeth are important in achieving pleasing dental and facial esthetics. However, little scientific data have been defined as criteria for evaluating these morphological features. PURPOSE: This study analyzed the clinical crown dimensions of maxillary anterior teeth to determine whether consistent relationships exist between tooth width and several facial measurements in a subset of the Turkish population. MATERIAL AND METHODS: Full-face and anterior tooth images of 100 Turkish dental students viewed from the front and engaged in maximum smiling were recorded with digital photography under standardized conditions. Gypsum casts of the maxillary arches of the subjects were also made. The dimensions of the anterior teeth, the occurrence of the golden ratio, the difference between the actual and perceived sizes, and the relationship between the anterior teeth and several facial measurements by gender were analyzed using the information obtained from both the computer images and the casts. One-sample, 2-sample, and paired t tests, and repeated-measures analysis of variance and Duncan multiple-range tests were performed to analyze the data (alpha=.05). RESULTS: The dimensions of the central incisors (P<.05) and canines (P<.01) varied by gender. The existence of the so-called "golden proportion" for the maxillary anterior teeth as a whole was not found. Significant differences emerged when the mean ratios between various perceived widths were compared with their ideal golden ratios (P<.01). Proportional relationships between the bizygomatic width and the width of the central incisor, and the intercanine distance and the interalar width in women were observed. CONCLUSION: The maxillary central incisor and canine dimensions of men were greater than those of women in the Turkish population studied, with the canines showing the greatest gender variation. Neither a golden proportion nor any other recurrent proportion for all anterior teeth was determined. Bizygomatic width and interalar width may serve as references for establishing the ideal width of the maxillary anterior teeth, particularly in women.

Adult↗
PubMed2006

Clinical evaluation of pulpless teeth restored with conventionally cemented zirconia posts: a pilot study.

STATEMENT OF PROBLEM: Adhesive resin cements are commonly used to lute all-ceramic posts despite limited scientific data on the clinical effectiveness of using bonding agents within prepared root canals. PURPOSE: The purpose of this study was to retrospectively evaluate the clinical performance of conventionally cemented zirconia posts. Loss of retention, fracture of posts, and fracture of teeth were evaluated. MATERIAL AND METHODS: Thirty pulpless teeth in 22 patients were treated with zirconia posts. With the exception of 3 situations in which posts were inserted directly and the access openings were closed with composite resin, teeth were restored with indirectly fabricated post-and-core foundations made from zirconia posts (Cerapost or Cosmopost) combined with heat-pressed ceramic cores (IPS Empress Cosmo) and ceramic crowns (IPS Empress II). Restorations (posts and crowns) were cemented with glass-ionomer cement (KetacCem) or resin-modified glass-ionomer cement (ProTec Cem) and reevaluated, retrospectively, for failures such as loss of retention or fractures. Data were reported using descriptive statistics. RESULTS: The mean observation period was 29 months (range 8-44 months). No loss of retention or fracture of any restoration was observed. CONCLUSION: Although this study involved a relatively short observation period, there were no signs of failure of conventionally cemented zirconia posts with ceramic crowns.

Crowns↗
PubMed2005

Dermatoxin and phylloxin from the waxy monkey frog, Phyllomedusa sauvagei: cloning of precursor cDNAs and structural characterization from lyophilized skin secretion.

Amphibian skin is a morphologically, biochemically and physiologically complex organ that performs the wide range of functions necessary for amphibian survival. Here we describe the primary structures of representatives of two novel classes of amphibian skin antimicrobials, dermatoxin and phylloxin, from the skin secretion of Phyllomedusa sauvagei, deduced from their respective precursor encoding cDNAs cloned from a lyophilized skin secretion library. A degenerate primer, designed to a highly conserved domain in the 5'-untranslated region of analogous peptide precursor cDNAs from Phyllomedusa bicolor, was employed in a 3'-RACE reaction. Peptides with molecular masses coincident with precursor-deduced mature toxin peptides were identified in LC/MS fractions of skin secretion and primary structures were confirmed by MS/MS fragmentation. This integrated experimental approach can thus rapidly expedite the primary structural characterization of amphibian skin peptides in a manner that circumvents specimen sacrifice whilst preserving robustness of scientific data.

Amino Acid Sequence↗
PubMed2005

[Diagnostic value of the clinical probability score of deep venous thrombosis in the elderly].

SUBJECT: There is a lack of scientific data concerning the incidence, clinical signs, risk factors and diagnostic management of deep vein thrombosis (DVT) in the elderly. METHODS: We carried out a prospective case-control study in a geriatric setting. We included one in-patient without clinical signs of deep vein thrombosis for each hospitalised patient with clinically suspected DVT. Clinical signs, risk factors of DVT and a compression ultrasonography of the proximal and distal leg veins were performed in all patients at admission. Also, the clinical probability was assessed by means of the clinical score model described by Wells. RESULTS: There were 102 patients aged over 85 included during the 5 months period of the study. Fifty-one patients have had a clinical suspicion of DVT and 51 patients were clinically asymptomatic. There were 43% symptomatic DVT and 12% asymptomatic DVT. Clinical signs and symptoms of DVT were neither sensitive nor specific. Risk factors associated most frequently with DVT were: immobilisation (prevalence 64%), paralysis of the legs (22%), varicose veins (25%), deshydratation (28,5%), infections (18%). A significant relationship between a risk factor and DVT was found only for immobilisation (P<0,05) and deshydratation (P<0,02). The prevalence of DVT increased with the clinical probability score: 11.4% for the low score, 27.6% for the moderate score and 55% for the high score. CONCLUSION: Incidence of DVT is high among hospitalised elderly patients, especially for the asymptomatic ones. Clinical signs alone do not reliably predict DVT. Clinical probability score could be useful to improve diagnostic management of DVT in this population.

Aged↗
PubMed2006

FDA perspectives on health claims for food labels.

The U.S. Food and Drug Administration's regulatory authority over health claims was clarified in 1990 legislation known as the Nutrition Labeling and Education Act (NLEA). This law established mandatory nutrition labeling for most foods and placed restrictions on the use of food label claims characterizing the levels or health benefits of nutrients in foods. NLEA set a high threshold for the scientific standard under which the U.S. Food and Drug Administration (FDA) may authorize health claims, this standard is known as the significant scientific agreement (SSA) standard. Subsequent legislation known as the Food and Drug Administration Modernization Act (FDAMA) provided an alternative to FDA review of the health claim where an U.S. government scientific body other than FDA concluded that there is SSA for a substance/disease relationship. Courts have since extended the scope of health claims to include qualified health claims (QHC) that are health claims not substantiated on evidence that meets the level of SSA standard, but include a qualifying statement intended to convey to the consumer the level of evidence for the claim. FDA has responded by developing an evidence-based ranking system for scientific data to determine the level of evidence substantiating a health claim. The following is an overview of FDA's regulations and evidence-based method for evaluating health claims.

Food Labeling↗
PubMed2005

Biological monitoring and Biological Limit Values (BLV): the strategy of the European Union.

Occupational standards concerning allowable concentrations of chemical compounds in the ambient air of workplaces have been established in several countries worldwide. With the integration of the European Union (EU), there has been a need of establishing harmonised Occupational Exposure Limits (OEL). The European Commission Directive 95/320/EC of 12 July 1995 has given the tasks to a Scientific Committee for Occupational Exposure Limits (SCOEL) to propose, based on scientific data and where appropriate, occupational limit values which may include the 8-h time-weighted average (TWA), short-term limits/excursion limits (STEL) and Biological Limit Values (BLVs). In 2000, the European Union issued a list of 62 chemical substances with Occupational Exposure Limits. Of these, 25 substances received a "skin" notation, indicating that toxicologically significant amounts may be taken up via the skin. For such substances, monitoring of concentrations in ambient air may not be sufficient, and biological monitoring strategies appear of potential importance in the medical surveillance of exposed workers. Recent progress has been made with respect to formulation of a strategy related to health-based BLVs.

Air Pollutants, Occupational↗
PubMed2006

Oral squamous cell carcinoma: review of prognostic and predictive factors.

Oral squamous cell carcinoma has a remarkable incidence worldwide and a fairly onerous prognosis, encouraging further research on factors that might modify disease outcome. In this review article, the authors approach the factors that may exert influence on the prognosis and eventually guide the selection of patients for more aggressive therapies. Published scientific data was collected, selected, and grouped into 3 main clusters: patient-, tumor-, and treatment-related factors. Well established aspects are discussed, but also those less common or with only supposed usefulness. Disease staging, extracapsular dissemination, resection margin free of disease, and tumor thickness are factors with high influence on the prognosis. There has been an increasing interest in the study of tumor molecular factors, and some have been strongly correlated with the outcome, showing promising pathways for the future development of more effective prognosis systems and anticancer therapies.

Age Factors↗
PubMed2006

Complementary and alternative medicine for advanced prostate cancer.

Complimentary and alternative medicines (CAM) have increased drastically in popularity in the past decade. These are largely in the form of nutritional supplements. Despite a wealth of information sources on the subject, the fundamental problem with CAM therapies is a dearth of evidence-based medicine. Advanced prostate cancer has significant long-term morbidity, and there is a growing interest in alternative and complimentary forms of therapy that will improve the outcomes of patients who have recurrent or advanced prostate cancer while obviating the need for more toxic forms of therapy. In this article we summarize the use of some of the more common CAM nutritional supplements and review the scientific data that are available to support their use.

Antioxidants↗
PubMedDate not supplied

An update on randomized clinical trials in localized and locoregional prostate cancer.

It is important that treatment decisions be based upon scientific data, as opposed to anecdotal experience and expert opinion. The goal of this article is to provide an update on phase III clinical trials in localized and locoregional prostate cancer. Studies comparing surgery and observation for localized disease are reviewed, as are studies comparing various forms of radiotherapy. The effectiveness of certain neoadjuvant and adjuvant therapies is also addressed. Although there are numerous phase III studies ongoing in these areas, there are still large gaps in our understanding of the treatment of localized disease, and additional clinical trials are needed.

Chemoprevention↗
PubMed2004

Oxytetracycline as a predisposing condition for chalkbrood in honeybee.

Antibiotics, particularly oxytetracycline, have been discussed as a possible predisposing condition in the appearance of chalkbrood in the honeybee (Apis mellifera L.). Nevertheless, the scientific data to support this belief have been insufficient. We have developed a method to study the effects of this antibiotic as a predisposing factor under different circumstances. We conclude that oxytetracycline does not increase the risk of chalkbrood in susceptible worker brood in the short or mid-term.

Analysis of Variance↗
PubMed2003

Health benefits and potential risks related to consumption of fish or fish oil.

The nutritional benefits of fish consumption relate to the utilization of proteins of high biological value, as well as certain minerals and vitamins that fish provide. Fish or fish oil contains omega-3 polyunsaturated fatty acids (PUFAs) that appear to play several useful roles for human health. Conversely, some carcinogenic contaminants are also stored in the adipose tissue of fish. The objective of this paper is to evaluate the potential health benefits and risks related to the consumption of fish or fish oil. Health benefits related to the consumption of fish or omega-3 PUFAs were obtained by an extensive literature search. Potential health risks related to carcinogenic contaminants (e.g., dioxin, PCB, etc.) in fish were estimated using the U.S. EPA-approved cancer risk assessment guidelines. Potential health risk estimates were evaluated by comparing them with the acceptable excess risk level of 10(-6)-10(-4). Scientific data indicate that the consumption of fish or fish oil containing omega-3 PUFAs reduces the risk of coronary heart disease, decreases mild hypertension, and prevents certain cardiac arrhythmias and sudden death. Risk estimates in humans for carcinogenic environmental contaminants in fish ranged from an excess risk level of 3x10(-6)-9x10(-4). These risk estimates appeared to meet the acceptable excess risk level criteria. Therefore, consumption of fish in accordance with the State of Michigan Fish Advisory Guidelines is safe and should be encouraged. The top 11 fish species [e.g., sardines, mackerel, herring (Atlantic and Pacific), lake trout, salmon (Chinook, Atlantic, and Sockeye), anchovy (European), sablefish, and bluefish] provide an adequate amount of omega-3 PUFAs (2.7-7.5g/meal) and appear to meet the nutritional recommendation of the American Heart Association.

American Heart Association↗
PubMed2006

The development and regulation of occupational exposure limits in China.

Of the 700 million workers in China, approximately 200 million workers are potentially exposed to industrial hazards. Although the promulgation and implementation of occupational exposure limits (OELs) in China began in the mid-1950, a systematic approach was not formalized until the formation of the Subcommittee of Occupational Health Standards Setting (SOHSS) in 1981. More recently, the 2002 Occupational Disease Prevention and Control Act of the People's Republic of China created the legislative framework for the development and enforcement of OELs. The SOHSS, whose members are primarily health professionals, is the organization responsible for the development of recommended standards, under the auspices of the Ministry of Health. The philosophy of OEL development of the SOHSS consists of a two-step approach: (1) an initial health-based recommended standard is established based on scientific data, and (2) a final law-based standard takes into consideration both socioeconomic and technological feasibility. Governmental agencies such as the Centers for Diseases Control and Prevention and the Institutes of Public Health Supervision at the state, provincial or municipal levels are charged with the responsibilities of the enforcement of OELs. The process and challenges in the enforcement of OELs are discussed. A comparison is made between selected Chinese OELs and those in other countries. The OELs for benzene and industrial dusts (including silica) are discussed in some detail.

Carcinogens, Environmental↗
PubMed2000

Nutrition and multifetal pregnancy.

Largely because of assisted reproduction, the rate of multifetal pregnancy is rising rapidly in the United States. Accordingly, dietitians are increasingly being called upon to provide nutrition services for these high-risk pregnancies. This article gives an overview of the incidence of and risks associated with multifetal pregnancy and reviews studies that contribute to our knowledge of nutrition and multifetal pregnancy. Practice guidelines for promoting healthy outcomes based on the best available scientific data are suggested. Guidelines for weight gain for twin and triplet pregnancy, dietary intake, and supplement use are included. Suggested practice guidelines for multifetal pregnancy include a positive rate of weight gain early in pregnancy, the use of prepregnancy weight status to determine total weight gain goals in twin pregnancy, a 50-lb weight gain goal for triplet pregnancy, and higher minimal number of servings of foods from several of the Food Guide Pyramid groups. The need for additional information on the effects of nutritional status on the course and outcome of multifetal pregnancy is critical. Preliminary evidence of the benefits of nutrition services suggests that both the incorporation of dietetics services into care programs and additional research on nutrition and multifetal gestation are warranted.

Diet↗
PubMed2000

Position of the American Dietetic Association, Dietitians of Canada, and the American College of Sports Medicine: Nutrition and athletic performance.

It is the position of the American Dietetic Association, Dietitians of Canada, and the American College of Sports Medicine that physical activity, athletic performance, and recovery from exercise are enhanced by optimal nutrition. These organizations recommend appropriate selection of food and fluids, timing of intake, and supplement choices for optimal health and exercise performance. This position paper reviews the current scientific data related to the energy needs of athletes, assessment of body composition, strategies for weight change, the nutrient and fluid needs of athletes, special nutrient needs during training, the use of supplements and nutritional ergogenic aids, and the nutrition recommendations for vegetarian athletes. During times of high physical activity, energy and macronutrient needs--especially carbohydrate and protein intake--must be met in order to maintain body weight, replenish glycogen stores, and provide adequate protein for building and repair of tissue. Fat intake should be adequate to provide the essential fatty acids and fat-soluble vitamins, as well as to help provide adequate energy for weight maintenance. Overall, diets should provide moderate amounts of energy from fat (20% to 25% of energy); however, there appears to be no health or performance benefit to consuming a diet containing less than 15% of energy from fat. Body weight and composition can affect exercise performance, but should not be used as the sole criterion for sports performance; daily weigh-ins are discouraged. Consuming adequate food and fluid before, during, and after exercise can help maintain blood glucose during exercise, maximize exercise performance, and improve recovery time. Athletes should be well-hydrated before beginning to exercise; athletes should also drink enough fluid during and after exercise to balance fluid losses. Consumption of sport drinks containing carbohydrates and electrolytes during exercise will provide fuel for the muscles, help maintain blood glucose and the thirst mechanism, and decrease the risk of dehydration or hyponatremia. Athletes will not need vitamin and mineral supplements if adequate energy to maintain body weight is consumed from a variety of foods. However, supplements may be required by athletes who restrict energy intake, use severe weight-loss practices, eliminate one or more food groups from their diet, or consume high-carbohydrate diets with low micronutrient density. Nutritional ergogenic aids should be used with caution, and only after careful evaluation of the product for safety, efficacy, potency, and whether or not it is a banned or illegal substance. Nutrition advice, by a qualified nutrition expert, should only be provided after carefully reviewing the athlete's health, diet, supplement and drug use, and energy requirements.

Altitude↗
PubMed2002

Position of the American Dietetic Association: the role of dietetics professionals in health promotion and disease prevention.

In the United States, the leading determinants of morbidity and mortality are rooted in behavioral choices related to eating habits, exercise, tobacco, alcohol consumption, and stress reduction. Scientific data consistently provide evidence that diet plays an important role in health promotion and disease prevention. Healthy eating habits--coupled with other healthful lifestyle behaviors--have the potential to reduce the risk of chronic disease. Health care typically assumes a curative or treatment role in the United States. However, dietetics professionals are shaping an alternate view of health, which includes developing healthy public policies, creating safe and supportive environments, building communities and coalitions, and reorienting health services to include health promotion as a primary approach to delivering health care. Individual-level approaches, such as counseling and group education, have been employed most often in modifying health behaviors. However, population-level approaches that affect availability of or access to healthy foods, opportunities for physical activity, and other healthy lifestyle determinants also are important. Dietetics professionals have pivotal roles in both individual- and population-level approaches.

Dietetics↗
PubMed2003

A randomized controlled trial of a Chinese herbal remedy to increase energy, memory, sexual function, and quality of life in elderly adults in Beijing, China.

BACKGROUND: Chinese herbal medicines are commonly used to improve general health and well-being despite limited scientific data to support their efficacy. We conducted a randomized, double-blind, placebo-controlled trial to determine whether an herbal remedy that is used widely in China was associated with changes in quality of life, energy, memory, sexual function, and qi (the Chinese concept of "vital energy" that is important in general health). METHODS: Residents (n = 237) of Beijing, China, who were aged > or =60 years and had self-reported decreased energy, memory, or sexual function, were randomly assigned to take four tablets of a Chinese herbal formula or of an identical placebo, three times a day for 30 days. Patients returned for one follow-up visit after 30 days for assessment of all outcomes. The main outcome measures were changes in quality of life at 30 days as measured by the 12-Item Short Form Health Survey (SF-12) Mental and Physical Component Summary scales. RESULTS: Use of Chinese herbs was associated with a small benefit in the Mental Component scale (difference of 1.9 points; 95% confidence interval [CI]: 0.1 to 3.6) and no benefit in the Physical Component scale (difference of -0.1 points; 95% CI: -1.7 to 1.5) as compared with placebo. A small improvement in the qi scale was no longer significant after adjusting for baseline differences in this score between groups. There was no improvement in physical performance, memory, or sexual function. The herbal product was well tolerated. CONCLUSION: Short-term use of a mixture of Chinese herbs was associated with a small benefit in one measure of mental health that is of unclear clinical importance.

Aged↗
PubMed1999

Postexposure prophylaxis for human immunodeficiency virus (HIV) infection following sexual assault.

Although the 1998 Centers for Disease Control and Prevention's guidelines for treatment of sexually transmitted diseases recommend offering postexposure prophylaxis for human immunodeficiency virus (HIV) infection following sexual assault, there are no detailed protocols on how to provide this treatment. Postexposure prophylaxis has been shown to lower the risk of seroconversion following occupational exposure to HIV by 81%, but has not yet been evaluated following sexual exposure. Though scientific data are limited, victims of sexual assault should be given the best information available to make an informed decision regarding postexposure prophylaxis. When the choice is made to take medications to prevent HIV infection, treatment should be initiated as soon as possible, but no later than 72 hours following the assault, and should be continued for 28 days. HIV postexposure prophylaxis should be provided in the context of a comprehensive treatment and counseling program that recognizes the physical and psychosocial trauma experienced by victims of sexual assault.

Anti-HIV Agents↗