Where Are Zoos Going—or Are They Gone?

ABSTRACT

To some, zoos are prisons exploiting animals. In reality zoos range from bad to better. I make this distinction: A bad zoo makes animals work for it; a good zoo works for animals. Good zoos do effective conservation work and continually strive to improve exhibits, relevance to conservation, and inspiring public engagement for wildlife. Many zoos have improved enormously; the better ones being crucial in saving species that would have otherwise gone extinct. Nonetheless, for some people the mere word “zoo” carries impressions of old zoos, bad zoos, circuses, and theme-park shows that many find distasteful. Good zoos know they must innovate forward. As society grows increasingly estranged from nature and continues driving broad declines of wildlife, wild lands, and natural systems, the goal of zoos and every organization concerned with animal welfare should not be to separate humans from other animals, but to entangle all humans in nonhuman lives. Zoos of the next decades must become the first stage in bringing young people into life-long, engaged caring about animals. They could carry on that mission in their communities, in schools, in wild lands, as well as inside their gates. Without a strong public constituency, wild animals will not withstand continued human proliferation. Zoos and aquariums must innovate toward being a crucial force abetting the continued existence of wildness on Earth. Zoos of the future must become uplifting places of respect, rescue, enhancement, conservation, and public engagement.     

The Feet of Overweight and Obese Young Children: Are They Flat or Fat?

Objective: The purpose of this study was to determine whether the flat feet displayed by young obese and overweight children are attributable to the presence of a thicker midfoot plantar fat pad or a lowering of the longitudinal arch relative to that in non‐overweight children. Research Methods and Procedures: Foot anthropometry, an arch index derived from plantar footprints, and midfoot plantar fat pad thickness measured by ultrasound were obtained for 19 overweight/obese preschool children (mean age, 4.3 ± 0.9 years; mean height, 1.07 ± 0.1 m; mean BMI, 18.6 ± 1.2 kg/m²) and 19 non‐overweight children matched for age, height, and sex (mean age, 4.3 ± 0.7 years; mean height, 1.05 ± 0.1 m; mean BMI, 15.7 ± 0.7 kg/m²). Results: Independent t tests revealed no significant between‐subject group differences (p = 0.39) in the thickness of the midfoot plantar fat pad. However, the overweight/obese children had a significantly lower plantar arch height (0.9 ± 0.3 cm) than their non‐overweight counterparts (1.1 ± 0.2 cm; p = 0.04). Discussion: The lower plantar arch height found in the overweight/obese children suggests that the flatter feet characteristic of overweight/obese preschool children may be caused by structural changes in their foot anatomy. It is postulated that these structural changes, which may adversely affect the functional capacity of the medial longitudinal arch, might be exacerbated if excess weight bearing continues throughout childhood and into adulthood.     

Sauropod Necks: Are They Really for Heat Loss?

Three-dimensional digital models of 16 different sauropods were used to examine the scaling relationship between metabolism and surface areas of the whole body, the neck, and the tail in an attempt to see if the necks could have functioned as radiators for the elimination of excess body heat. The sauropod taxa sample ranged in body mass from a 639 kg juvenile Camarasaurus to a 25 t adult Brachiosaurus. Metabolism was assumed to be directly proportional to body mass raised to the ¾ power, and estimates of body mass accounted for the presence of lungs and systems of air sacs in the trunk and neck. Surface areas were determined by decomposing the model surfaces into triangles and their areas being computed by vector methods. It was found that total body surface area was almost isometric with body mass, and that it showed negative allometry when plotted against metabolic rate. In contrast, neck area showed positive allometry when plotted against metabolic rate. Tail area show negative allometry with respect to metabolic rate. The many uncertainties about the biology of sauropods, and the variety of environmental conditions that different species experienced during the groups 150 million years of existence, make it difficult to be absolutely certain about the function of the neck as a radiator. However, the functional combination of the allometric increase of neck area, the systems of air sacs in the neck and trunk, the active control of blood flow between the core and surface of the body, changing skin color, and strategic orientation of the neck with respect to wind, make it plausible that the neck could have functioned as a radiator to avoid over-heating.     

Red Fluorescing Phototrophic Picoplankton in the Laurentian Great Lakes: What Are They and What Are They Doing?

Epifluorescence microscopy, flow cytometry, and transmission electron microscopy were used to characterize the community of red fluorescing (emission >665 nm when excited with blue light) phototrophic picoplankton (RFPP) in lakes Huron and Michigan. A population of coccoid to ovate eukaryotic cells with a mean size of 1.2 μm dominated the RFPP community in both surface and deep water samples. Abundant prochlorophyte populations were not found in any samples. Comparisons of counts with epifluorescence microscopy and flow cytometry, revealed that RFPP were adequately enumerated with standard epifluorescence microscopy. These RFPP were significant contributors to total phototrophic picoplankton abundance in both lakes Michigan (24%) and Huron (18%), with maximum seasonal abundance during the May-June period (surface mixing layer temperatures, 3-9 °C). During thermal stratification, maximum vertical abundance was found in the metalimnion/hypolimnion at the 1-5% isolumes. RFPP were only minor contributors (1-7%) to total primary production. Growth rates of RFPP measured with dilution and small inocula growth experiments ranged from 0.05-1.0 d⁻¹. Microzooplankton grazing rates on RFPP measured with dilution experiments were similar to estimated growth rates, accounting for 52-280% of growth on any given date.     

Biogeography and Limno-terrestrial Tardigrades: Are They Truly Incompatible Binomials?

Due to the passive dispersal, tardigrades have been traditionally considered unsuitable for biogeographical studies. However, this paper provides some biogeographical and biological data supporting the possibility of using those animals to solve biogeographical problems at continental level.     

The Costs of Conspecifics: Are Social Distractions or Environmental Distractions More Salient?

Animals have limited attention that predisposes them to distraction, but the impact of different types of distraction is relatively unknown. We first conducted a discrimination experiment to ensure brown anoles (Anolis sagrei) responded appropriately to model predators (a rubber snake) and model conspecifics. We found anoles responded to the snake by suppressing looking and increasing locomotion, a marked difference than their response when presented with a conspecific. Next, we designed a prime and probe experiment to test the salience of social and environmental distractions on brown anoles. The social distraction consisted of a conspecific exemplar that was presented to the focal individual. Environmental distractions were vegetation that was moved at different speeds (ambient or vigorous) near the focal individual. Following 30 seconds of distraction with one of the three treatments, we presented the model snake, which was initially moved to within 1 m of a subject, and then moved closer until the subject looked in response to the approaching threat, and then fled. There was no effect of distractor on alert distance, but anoles distracted with the conspecific tolerated a closer approach with the model predator before fleeing than they did to either of the vegetative movements. These results cannot be explained by three other models of risk assessment and suggest that social cues distracted brown anoles more than environmental cues. These results may be generalizable to other social species that must simultaneously monitor conspecifics and assess predation risk.     

The Ecosystem: Model or Metaphor?

Industrial ecology offers an original way of looking at economic activities. The approach is based on an analogy between certain objects studied by the science of ecology (ecosystems, metabolisms, symbiosis, biocenosis, etc.) and industrial systems. However, this analogical relationship raises difficulties due to the various interpretations to which it is open. Although there is agreement regarding its heuristic function, the analogy can nevertheless be understood either as a model or as a metaphor. The present article first attempts to show how models differ from metaphors. It then sets out to justify the epistemological relevance of this distinction for industrial ecology research. The reflection should thus contribute to clarifying the debate on the (supposed or desired) role of analogy in the field of industrial ecology and heighten the interest this field of investigation represents for implementing sustainable development.     

Levels of Intervention: How Are They Used in Quebec Hospitals?

In order to promote better practices and communication around end-of-life decision-making, several Canadian hospitals in the province of Quebec have developed a tool called “Levels of Intervention” (LOI). No work to date has been published demonstrating improvement since these forms were implemented. The purpose of the present study was to obtain information about the use of LOI forms across Quebec hospitals and to identify gaps in practice as well as areas for improvement. A retrospective study was undertaken of 299 charts of patients who had died in three Quebec hospitals with a LOI ordered. Results were analysed through a principlism ethical framework. High compliance with the level of intervention ordered at the time of death was recorded, as well as high involvement of patient and/or family, demonstrating the efficiency of LOI in promoting respect for autonomy. Other results show delays in end-of-life care discussions in the course of the hospitalization. Only a small proportion of patients who died had a palliative care consultation, which may reflect equity issues in access to care. This study highlights the importance of the LOI in Quebec and the role it is playing in respect for end-of-life preferences as well as in the involvement of patients and families in the decision-making process. Training specific to end-of-life decision-making conversations would help support the LOI form’s use, as would developing provincial or national guidelines on the use of LOI to standardize organizational policies and practice around end-of-life care.     

Mothers' Perceptions of Their Adolescents' Weight Status: Are They Accurate?

Objective: To evaluate the accuracy of mothers’ perceptions of adolescents’ weight status. Research Methods and Procedures: Parent interviews and adolescent surveys (755) were conducted in an ethnically diverse sample from Project EAT (Eating among Teens). Results: Adolescent weight status was accurately assessed by 60% of mothers, underestimated by 35% of mothers, and overestimated by 5% of mothers. In multivariate analyses, mothers of female adolescents were about half as likely to underestimate their adolescent's weight status as mothers of male adolescents. Nonoverweight mothers were about half as likely as overweight mothers to underestimate their adolescent's weight status. Discussion: Most mothers are able to accurately assess their adolescent's weight status; however, adolescent gender and mothers’ weight status are related to accuracy. Mothers were more likely to underestimate their sons’ weights than their daughters’ weights, and overweight mothers were more likely to be inaccurate in their assessments than nonoverweight mothers. Findings suggest that the majority of parents do not need to be told that their children are overweight; instead, messages to parents of overweight teens should focus on how to provide support for healthy weight management.     

Intrinsically Disordered Regions in Serum Albumin: What Are They For?

Serum albumin is a major plasma protein in mammalian blood. The importance of this protein lies in its roles in both bioregulation and transport phenomena. Serum albumin binds various metal ions and participates in the transport and storage of fatty acids, bilirubin, steroids amino acids, and many other ligands, usually with regions of hydrophobic surface. Although the primary role of serum albumin is to transport various ligand, its versatile binding capacities and high concentration mean that it can assume a number of additional functions. The major goal of this article is to show how intrinsic disorder is encoded in the amino acid sequence of serum albumin, and how intrinsic disorder is related to functions of this important serum protein.     

Soil Microbial Bioassays: Quick and Relevant But Are They Useful?

Soil microorganisms are pivotal in ecological systems, it may not be possible to define an ecosystem where an impact on overall microorganism populations would not mean a severe impact on the ecosystem. They are as relevant to an ecosystem as any group of organisms could be. At the same time, it is very difficult to link impact on measurable microbial activities to ecological impacts. We lack the required understanding. The linkage fails because of: compensation processes—the ecological process is continued by organisms other than those measured; non-specific assays—the method used to measure activity may impose conditions that do not reflect ecological conditions and multiple and unknown interacting factors. Overall, the ambiguity in benefit/ detriment relationships for impacts on microbes is the largest problem. Here we describe several examples of successes and failures of soil microbial bioassays in applications related to soil cleanliness criteria and ecological risk assessment. The usefulness of the microbial bioassays remains in question.     

Preclinical Models for Studying NASH-Driven HCC: How Useful Are They?

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Psychosocial Care Needs of Melanoma Survivors: Are They Being Met?

Patients who have survived malignant melanoma for more than five years may lack the opportunity to talk about their burden. As a consequence their psychosocial care needs remain undetected and available supportive interventions may not be utilised. Therefore, the psychosocial burden of this patient group needs to be assessed using specific screening instruments. The aim of this study was to investigate the psychosocial burden of long-term melanoma survivors, their psychosocial care needs and the determinants of these needs. We wanted to find out if the use of professional support corresponds to the care needs defined by experts. Using the cancer registry of Rhineland-Palatinate, melanoma patients diagnosed at least 5 years before the survey were contacted by physicians. N = 689 former patients completed the Hornheide Questionnaire (short form HQ-S) to identify psychosocial support need (scale cut off ≥ 16 or item-based cut-off score) and the potential psychosocial determinants of these needs. Additionally, they were asked about their utilisation of the professional support system. More than one third (36%) of them was in need for professional psychosocial support. The highest burden scores concerned worry about tumour progression. Younger age (< 50), higher general fatigue, higher symptom burden, lower general health, negative social interactions and unfulfilled information needs were significant predictors of the need for psychosocial intervention. Related to the percentage of survivors identified as ‘in need’, the professional support system was underused. Further studies should investigate whether using the HQ-S to routinely identify burdened melanoma patients could lead to better fulfilment of their intervention needs, ultimately enhancing health-related quality of life.     

Are Phytochelatins Involved in Differential Metal Tolerance or Do They Merely Reflect Metal-Imposed Strain?

Plants from nontolerant and copper-tolerant populations of Silene vulgaris both produce phytochelatins upon exposure to copper. The threshold copper concentration for induction of phytochelatin and the copper concentration at which maximum phytochelatin contents occurs increase proportionally with the level of tolerance to copper. When exposed to their own highest no-effect concentration or 50%-effect concentration of copper for root growth, tolerant and nontolerant plants exhibit equal phytochelatin contents in the root apex, which is the primary copper target. This also holds for distinctly tolerant nonsegregating F₃ families, derived from a single cross of a nontolerant plant to a tolerant one. Therefore, the phytochelatin content of the root apex can be used as a quantitative tolerance-independent measure of the degree of toxicity experienced by the plant. Differential copper tolerance in S. vulgaris does not appear to rely on differential phytochelatin production.     

The Benefits of Photorespiratory Bypasses: How Can They Work?

Bypassing the photorespiratory pathway is regarded as a way to increase carbon assimilation and, correspondingly, biomass production in C₃ crops. Here, the benefits of three published photorespiratory bypass strategies are systemically explored using a systems-modeling approach. Our analysis shows that full decarboxylation of glycolate during photorespiration would decrease photosynthesis, because a large amount of the released CO₂ escapes back to the atmosphere. Furthermore, we show that photosynthesis can be enhanced by lowering the energy demands of photorespiration and by relocating photorespiratory CO₂ release into the chloroplasts. The conductance of the chloroplast membranes to CO₂ is a key feature determining the benefit of the relocation of photorespiratory CO₂ release. Although our results indicate that the benefit of photorespiratory bypasses can be improved by increasing sedoheptulose bisphosphatase activity and/or increasing the flux through the bypass, the effectiveness of such approaches depends on the complex regulation between photorespiration and other metabolic pathways.In C₃ plants, the first step of photosynthesis is the fixation of CO₂ by ribulose bisphosphate (RuBP). For every molecule of CO₂ fixed, this reaction produces two molecules of a three-carbon acid, i.e., 3-phosphoglycerate (PGA), and is catalyzed by the Rubisco enzyme. A small portion of the carbon in PGA is used for the production of Suc and starch, whereas the remainder (i.e. five-sixths) is used for the regeneration of RuBP (Fig. 1). The regeneration of the Rubisco substrate RuBP in the Calvin-Benson-Bassham (CBB) cycle ensures that ample RuBP is available for carbon fixation (Bassham, 1964; Wood, 1966; Beck and Hopf, 1982). Rubisco is a bifunctional enzyme that catalyzes not only RuBP carboxylation but also RuBP oxygenation (Spreitzer and Salvucci, 2002). RuBP oxygenation generates only one molecule of PGA and one molecule of 2-phosphoglycolate (P-Gly; Ogren, 1984). The photorespiratory pathway converts this P-Gly back to RuBP in order to maintain the CBB cycle.Open in a separate windowFigure 1.Schematic representation of the C3 photosynthesis kinetic model with three different photorespiratory bypass pathways. The bypass described by Kebeish et al. (2007) is indicated in blue, the bypass described by Maier et al. (2012) in pink, and the bypass described by Carvalho et al. (2011) in green. The original photorespiratory pathway is marked in orange, and CO₂ released from photorespiration (including the original pathway and bypass pathways) is indicated in red. 2PGA, 2-Phosphoglyceric acid; ASP, Asp; CIT, citrate; ICIT, isocitrate; PGA, 3-phosphoglycerate; DPGA, glycerate-1,3-bisphosphate; GAP, glyceraldehyde 3-phosphate; DHAP, dihydroxyacetone phosphate; SBP, sedoheptulose-1,7-bisphosphate; S7P, sedoheptulose-7-phosphate; Ri5P, ribose-5-phosphate; Ru5P, ribulose-5-phosphate; FBP, fructose-1,6-bisphosphatase; F6P, fructose 6-phosphate; Xu5P, xylulose-5-phosphate; G6P, glucose-6-phosphate; G1P, glucose-1-phosphate; ADPG, ADP-glucose; F26BP, fructose-2,6-bisphosphate; UDPG, uridine diphosphate glucose; SUCP, sucrose-6F-phosphate; SUC, Suc; PEP, phosphoenolpyruvate; OAA, oxaloacetate; PGCA, phosphoglycolate; GCA, glycolate; GOA, glyoxylate; GCEA, glycerate; MAL, malate; PYR, pyruvate; GLU, glutamate; KG, alfa-ketoglutarate; GLN, Gln; HPR, hydroxypyruvate; RuBP, ribulose bisphosphate; SER, Ser; GLY, Gly; TS, tartronic semialdehyde.In higher plants, P-Gly is dephosphorylated to glycolate, which is transferred into the peroxisomes, where it is oxidized to hydrogen peroxide and glyoxylate. Then, glyoxylate is aminated to produce Gly, which is subsequently transferred to the mitochondria. There, two molecules of Gly are converted into one Ser plus one CO₂ and one NH₃ (Ogren, 1984; Peterhansel et al., 2010). The Ser is ultimately converted back to PGA (Tolbert, 1997). CO₂ and NH₃ are gasses that can escape to the atmosphere (Sharkey, 1988; Kumagai et al., 2011), and the loss of carbon and nitrogen essential for biomass accumulation will decrease the efficiency of photosynthesis and plant growth (Zhu et al., 2010). Fortunately, both substances are partially reassimilated in the chloroplast, but this results in decreased photosynthetic energy efficiency. At 25°C and current atmospheric CO₂ concentrations, approximately 30% of the carbon fixed in C₃ photosynthesis may be lost via photorespiration and the size of this loss increases with temperature (Sharkey, 1988; Zhu et al., 2010). As a result, photorespiration has been regarded as a pathway that could be altered to improve photosynthetic efficiency (Zelitch and Day, 1973; Oliver, 1978; Ogren, 1984; Zhu et al., 2008, 2010).There are several approaches that may be used to alter photorespiration to improve photosynthetic efficiency. First, it might be possible to increase the specificity of Rubisco to CO₂ versus oxygen (S_c/o; Dhingra et al., 2004; Spreitzer et al., 2005; Whitney and Sharwood, 2007). However, previous studies have shown that there is an inverse correlation between S_c/o and the maximum carboxylation rate of Rubisco (Jordan and Ogren, 1983; Zhu et al., 2004), and there are some indications that the S_c/o of different organisms may be close to optimal for their respective environments (Tcherkez et al., 2006; Savir et al., 2010). Second, a CO₂-concentrating mechanism could be engineered into C₃ plants. For example, introducing cyanobacterial bicarbonate transporters (Price et al., 2011) or introducing C₄ metabolism could be used to concentrate CO₂ in the vicinity of Rubisco and, thereby, suppress the oxygenation reaction of Rubisco (Furbank and Hatch, 1987; Mitchell and Sheehy, 2006). Past efforts to introduce a C₄ pathway into C₃ plants have focused on biochemical reactions related to C₄ photosynthesis without taking into account the anatomical differences between C₃ and C₄ plants, which may have been responsible for the limited success of such endeavors (Fukayama et al., 2003). Recently, there has been renewed interest in engineering C₄ photosynthetic pathways into C₃ plants, with efforts focusing on understanding and engineering the genetic regulatory network related to the control of both the anatomical and biochemical properties related to C₄ photosynthesis (Mitchell and Sheehy, 2006; Langdale, 2011).Transgenic approaches have been used to knock down or knock out enzymes in the photorespiratory pathway. Unfortunately, the inhibition of photorespiration by the deletion or down-regulation of enzymes in the photorespiratory pathway resulted in a conditional lethal phenotype (i.e. such plants cannot survive under ambient oxygen and CO₂ concentrations but may be rescued by growing them under low-oxygen or high-CO₂ conditions; for review, see Somerville and Ogren, 1982; Somerville, 2001). Another approach to reduce photorespiration is to block (or inhibit) enzymes in this pathway using chemical inhibitors. Zelitch (1966, 1974, 1979) reported that net photosynthesis increased by inhibiting glycolate oxidase or glycolate synthesis. However, other groups showed that the inhibition of glycolate oxidase or Gly decarboxylation led to the inhibition of photosynthesis (Chollet, 1976; Kumarasinghe et al., 1977; Servaites and Ogren, 1977; Baumann et al., 1981). It turns out that plants cannot efficiently metabolize photorespiratory intermediates without a photorespiratory pathway, and suppression of this pathway inhibits the recycling of carbon back toward RuBP, which is necessary for maintaining the CBB cycle (Peterhansel et al., 2010; Peterhansel and Maurino, 2011). Moreover, the accumulation of toxic metabolic intermediates (e.g. P-Gly) can strongly inhibit photosynthesis (Anderson, 1971; Kelly and Latzko, 1976; Chastain and Ogren, 1989; Campbell and Ogren, 1990). This may explain why earlier attempts to block or reduce photorespiration have failed to improve carbon gain.Instead of reducing photorespiration directly, a promising idea is to engineer a photorespiratory bypass pathway. Such a pathway would metabolize P-Gly produced by RuBP oxygenation but minimize carbon, nitrogen, and energy losses and avoid the accumulation of photorespiratory intermediates. Kebeish et al. (2007) introduced the glycolate catabolic pathway from Escherichia coli into Arabidopsis (Arabidopsis thaliana); we will subsequently call this type of bypass the Kebeish bypass. In such transgenic plants, glycolate is converted to glycerate in the chloroplasts without ammonia release (Fig. 1). Previous studies suggested that this pathway theoretically requires less energy and shifts CO₂ release from mitochondria to chloroplasts (Peterhansel and Maurino, 2011; Peterhansel et al., 2013); experimental results indicated that the bypass allowed for increased net photosynthesis and biomass production in Arabidopsis (Kebeish et al., 2007). There are reports of two other photorespiratory bypass pathways in the literature (Carvalho, 2005; Carvalho et al., 2011; Maier et al., 2012). In the Carvalho bypass (Carvalho, 2005; Carvalho et al., 2011), glyoxylate is converted to hydroxypyruvate in the peroxisome. Similar to the Kebeish bypass, the ammonia release is abolished, one-quarter of the carbon from glycolate is released as CO₂ in the peroxisomes, and three-quarters of the carbon from glycolate is converted back to PGA. However, this pathway has only been partially realized in tobacco (Nicotiana tabacum); that is, the enzyme of the second reaction of this pathway was not detectable in the transgenic plants, and plants expressing this pathway showed stunted growth when grown in ambient air (Carvalho et al., 2011). The Maier bypass (Maier et al., 2012) is characterized by complete oxidation of glycolate in the chloroplasts. Initial results suggested that the photosynthesis and biomass of transgenic Arabidopsis with this pathway were enhanced (Maier et al., 2012).Recently, the design and benefits of the three bypass pathways were reviewed (Peterhansel et al., 2013), and it was suggested that a photorespiratory bypass can contribute to an enhanced photosynthetic CO₂ uptake rate by lowering energy costs and minimizing carbon and nitrogen losses. However, a systematic and quantitative analysis of the potential contributions of these different factors to photosynthesis improvement has not yet been conducted. Systems modeling can help to design new metabolic pathways and improve our understanding of biochemical mechanisms (McNeil et al., 2000; Wendisch, 2005; Zhu et al., 2007; Bar-Even et al., 2010; Basler et al., 2012). Such models have been used successfully to gain insight into the photosynthetic metabolism (Laisk et al., 1989, 2006; Laisk and Edwards, 2000; Zhu et al., 2007, 2013; Wang et al., 2014). In this study, we use an extended kinetic model of C₃ photosynthesis based on earlier work by Zhu et al. (2007) to systematically analyze the potential of three photorespiratory bypass pathways for improving photosynthetic efficiency (Supplemental Model S1). In addition, we determined under what conditions such bypass pathways may lead to increased photosynthesis and biomass production in C₃ plants and how to further improve the photosynthesis of plants with such a bypass. Our analysis suggests that the benefit of a photorespiratory bypass varies dramatically if it is engineered into different crops.     

Weight-Loss Strategies Used by the General Population: How Are They Perceived?

Background

The rising prevalence of obesity and the social pressure for thinness increase the prevalence of dieting. However, little is known about the overall perception of dieting strategies actually used by the general population.

Objectives

Our main objective was to investigate perceptions of weight-loss practices in an observational study in order to identify the most favourable strategy.

Design

Adults from the ongoing Nutrinet-Santé cohort study who had reported engaging in dieting in the three previous years were included in the study. For each diet, detailed information was collected on types of diets, circumstances and perception of the diet, and outcomes. Perceptions were compared across diets using sex-specific mixed effects models.

Result

Among the 48 435 subjects who had completed the respective questionnaire, 12 673 (26.7%, 87.8% of women) had followed at least one weight-loss diet in the previous three years. Diet plans prescribed by health professionals and diets conforming to official dietary recommendations were the most favourably perceived among all assessed weight-loss strategies. Alternatively, commercial diet plans and self-imposed dietary restrictions were more negatively perceived (Odds ratios (OR) for adherence difficulty 1.30 (95% confidence interval (0.99;1.7)) in men and OR 1.92 (1.76;2.10) in women compared to official nutritional guidelines; OR 1.06 (0.82;1.38) in men and OR 1.39 (1.26;1.54) in women respectively) compared to official nutritional guidelines.

Conclusion

Official dietary recommendations could be useful tools for maintaining a dietary balance while following a weight-loss diet.     

Drug Users in Amsterdam: Are They Still at Risk for HIV?

Background and Aims

To examine whether drug users (DU) in the Amsterdam Cohort Study (ACS) are still at risk for HIV, we studied trends in HIV incidence and injecting and sexual risk behaviour from 1986 to 2011.

Methods

The ACS is an open, prospective cohort study on HIV. Calendar time trends in HIV incidence were modelled using Poisson regression. Trends in risk behaviour were modelled via generalized estimating equations. In 2010, a screening for STI (chlamydia, gonorrhoea and syphilis) was performed. Determinants of unprotected sex were studied using logistic regression analysis.

Results

The HIV incidence among 1298 participants of the ACS with a total follow-up of 12,921 person-years (PY) declined from 6.0/100 PY (95% confidence interval [CI] 3.2–11.1) in 1986 to less than 1/100 PY from 1997 onwards. Both injection and sexual risk behaviour declined significantly over time. Out of 197 participants screened for STI in 2010–2011, median age 49 years (IQR 43–59), only 5 (2.5%) were diagnosed with an STI. In multivariable analysis, having a steady partner (aOR 4.1, 95% CI 1.6–10.5) was associated with unprotected sex. HIV-infected participants were less likely to report unprotected sex (aOR 0.07, 95% CI 0.02–0.37).

Conclusions

HIV incidence and injection risk behaviour declined from 1986 onwards. STI prevalence is low; unprotected sex is associated with steady partners and is less common among HIV-infected participants. These findings indicate a low transmission risk of HIV and STI, which suggests that DU do not play a significant role in the current spread of HIV in Amsterdam.