Low-carbohydrate diets affect energy balance and fuel homeostasis differentially in lean and obese rats

In parallel with increased prevalence of overweight people in affluent societies are individuals trying to lose weight, often using low-carbohydrate diets. Nevertheless, long-term metabolic consequences of those diets, usually high in (saturated) fat, remain unclear. Therefore, we investigated long-term effects of high-fat diets with different carbohydrate/protein ratios on energy balance and fuel homeostasis in obese (fa/fa) Zucker and lean Wistar rats. Animals were fed high-carbohydrate (HC), high-fat (HsF), or low-carbohydrate, high-fat, high-protein (LC-HsF-HP) diets for 60 days. Both lines fed the LC-HsF-HP diet displayed reduced energy intake compared with those fed the HsF diet (Zucker, -3.7%) or the HC diet (Wistar rats, -12.4%). This was not associated with lower weight gain relative to HC fed rats, because of increased food efficiencies in each line fed HsF and particularly LC-HsF-HP food. Zucker rats were less glucose tolerant than Wistar rats. Lowest glucose tolerances were found in HsF and particularly in LC-HsF-HP-fed animals irrespective of line, but this paralleled reduced plasma adiponectin levels, elevated plasma resistin levels, higher retroperitoneal fat masses, and reduced insulin sensitivity (indexed by insulin-induced hypoglycemia) only in Wistar rats. In Zucker rats, however, improved insulin responses during glucose tolerance testing and tendency toward increased insulin sensitivities were observed with HsF or LC-HsF-HP feeding relative to HC feeding. Thus, despite adverse consequences of LC-HsF diets on blood glucose homeostasis, principal differences exist in the underlying hormonal regulatory mechanisms, which could have benefits for B-cell functioning and insulin action in the obese state but not in the lean state.

The construction of Gender Dysphoria at 'Classifying Sex: Debating DSM-5'

On the American Psychiatric Association’s (APA) website the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5), is promoted as the “most comprehensive, current, and critical resource for clinical practice available to today's mental health clinicians and researchers of all orientations” (American Psychiatric Association, 2012a). The manual is ‘comprehensive,’ indeed; it has grown in size since its first edition to over 900 pages in its current DSM 5 incarnation. We could argue as Farley, the former president of the American Psychological Association, does that the DSM authors are contributing to an increase in “the relentless production of disorders and pathologizing of normal extremes” (Gornall, 2013: no page no.) and the facilitating of mental illnesses. In response to the publication of the DSM-5, a two-day conference at the University of Cambridge took place: Classifying Sex: Debating DSM-5, at which discussants debated the potential impact of the manual’s criteria for pathological, paraphilic and by default ‘normal’ sexualities, gender identities, and psychiatric practice. The delegates considered amongst many other topics the role of power and evidence, at least that is how I understood many of the contributions to the debate. The panel that I was invited to contribute to featured Kenneth Zucker (Chair of the Sexual and Gender Identity Disorders workgroup of DSM-5) to whom I was to critically respond. In this reflective commentary I would like to focus on power and evidence because Zucker has previously described the DSM’s international influence as spreading from clinical care, clinical training to clinical research (Zucker, 2010b). Moreover, in Zucker’s conference talk: The Science and Politics of DSM-5 (Zucker, 2013) it invoked these conceptual frameworks. Zucker’s intriguing first presentation slide read: “Power is the ultimate aphrodisiac (Henry Kissinger 1973).” This was followed by a slide illustrating the sum of publications Zucker and the other Chairs of the DSM-5 working groups had published accompanied by Zucker’s remarks that these publications were part of the reason why they were selected by the APA’s Board of Trustees (BOT) and as Chairs of their respective work groups. This generated in me a sense that power and evidence to support these tangled, conflicting positions of power were being played out in a number of domains, profiting from many tactical partnerships (Foucault, 1998 [1984]): the BOT, the contributors to the working groups, the academe and in some cases the (parents of) patients themselves through data from the clinics

Cyclooxygenase-2 Inhibition Restored Endothelium-Mediated Relaxation in Old Obese Zucker Rat Mesenteric Arteries

Metabolic syndrome is associated with reduced endothelial vasodilator function. It is also associated with the induction of cyclooxygenase-2 (COX2), which produces vasoactive prostanoids. The frequency of metabolic syndrome increases with age and aging per se is a risk factor associated with reduced endothelium-mediated relaxation. Nevertheless, the combined effect of aging and metabolic syndrome on the endothelium is less known. We hypothesized that COX2 derived prostanoids may affect endothelium function in metabolic syndrome associated with aging. We used obese Zucker rats, a model of metabolic syndrome. First order mesenteric arteries were isolated from 4- and 12-month-old rats and acetylcholine (endothelium)-dependent relaxation determined using wire-myography. Endothelium-mediated relaxation, impaired in young Zucker rats (89 versus 77% maximal relaxation; lean versus Zucker), was further reduced in old Zucker rats (72 versus 51%, lean versus Zucker). The effect of the nitric oxide-synthesis inhibitor L-NAME on the relaxation was reduced in both young and old Zucker rats without change in eNOS expression level. COX inhibition (indomethacin) improved acetylcholine-mediated relaxation in old obese rats only, suggesting involvement of vasoconstrictor prostanoids. In addition, COX2 inhibition (NS398) and TxA2/PGH2 receptor blockade (SQ29548) both improved relaxation in old Zucker rat arteries. Old Zucker rats had the highest TxB2 (TxA2 metabolite) blood level associated with increased COX2 immunostaining. Chronic COX2 blockade (Celecoxib, 3 weeks) restored endothelium-dependent relaxation in old Zucker rats to the level observed in old lean rats. Thus the combination of aging and metabolic syndrome further impairs endothelium-dependent relaxation by inducing an excessive production of COX2-derived vasoconstrictor(s); possibly TxA2

Gene expression profiling in the intestinal mucosa of obese rats administered probiotic bacteria

This paper will be part of Candido Robles-Sanchez's doctorate, which is being completed as part of the 'Biochemistry and Molecular Biology Program' at the University of Granada, Spain. This work was funded by the company Hero Spain, S. A. (grant #3545 managed by Fundacion General EmpresaUniversidad de Granada) and by CEIBiotic, University of Granada, Spain (grant CEI2013P-11).We investigated whether the administration of Lactobacillus paracasei CNCM I-4034, Bifidobacterium breve CNCM I-4035 and Lactobacillus rhamnosus CNCM I-4036 modulate the expression of genes in the intestinal mucosa of obese Zucker rats. Forty-eight Zucker-Lepr(fa/fa) and 16 Zucker lean Lepr(+/fa) rats were used. Eight Zucker lean Lepr(+/fa) and 8 Zucker-Lepr(fa/fa) rats were euthanized as a reference. The remaining 40 Zucker-Lepr(fa/fa) rats were then assigned to receive 10(10) colony forming units (CFU) of one of the three probiotic strains, a mixture of L. paracasei CNCM I-4034 and B. breve CNCM I-4035, or a placebo by oral administration for 30 days. An additional group of 8 Zucker lean Lepr(+/fa) rats received the placebo for 30 days. Over 27,000 rat genes were studied using a DNA array. Four animals per group were used. Total RNA was extracted from intestinal mucosa and cDNA was synthesized, fragmented and labeled. Labeled cDNA was hybridized using GeneChip kits, and the latter were scanned. Intensity values of each probe were processed and normalized to obtain an individual value for each set of probes.Company Hero Spain, S. A. 3545CEIBiotic, University of Granada, Spain CEI2013P-1

Do Classroom Teaching Methods Incorporate All Types of Learning Styles?

An individual’s learning style is a natural pattern of processing or acquiring knowledge. Three types of learning styles that were studied are visual, auditory, and kinesthetic (tactile). An individual’s ability to acquire knowledge depends upon the style of instruction received by the teacher. The purpose of this project was to examine whether the teaching methods used in a high school biology classroom take into account different types of student learning styles. Student teaching in a biology class has given the author the opportunity to study the learning needs of the students. The participants were given a questionnaire during class asking each student to answer questions that would reflect their preferred style of learning. The students were also asked what methods were used during instruction that satisfied their learning style needs or caused them to struggle. The author then analyzed the data from the questionnaire to determine if the students felt their learning needs were met

A note on big Ramsey degrees

Generalizing and simplifying recent work of Dobrinen, we show that if $\mathcal{L}$ is a finite binary relational language and $\mathcal{F}$ is a finite set of finite irreducible $\mathcal{L}$-structures, then the class $\mathcal{K} = \mathrm{Forb}(\mathcal{F})$ has finite big Ramsey degrees.Comment: A more complete introduction and an appendix on forcing have been added. The proof of Theorem 3.1 has been tweaked to more closely follow the presentation of the appendi