FTO expression is regulated by availability of essential amino acids.

Genome-wide association studies have revealed that single nucleotide polymorphisms in fat mass and obesity-associated transcript (FTO) are robustly associated with body mass index and obesity. Expression of Fto in the hypothalamic arcuate nucleus is bidirectionally regulated as a function of nutritional status; decreasing following a 48-h fast and increasing after 10-week exposure to a high-fat diet. Here, we utilize an in vitro approach to determine which nutrients could regulate FTO levels at a cellular level. Using mouse and human cell lines, we find that FTO levels are not influenced by serum starvation. We demonstrate, however, that both glucose and total amino-acid deprivation regulates FTO expression. In particular, we have found that FTO mRNA and protein levels are dramatically downregulated by total amino-acid deprivation in mouse hypothalamic N46 cells, mouse embryonic fibroblasts and in human HEK293 cells. The drop rate of Fto mRNA is faster than its rate of natural degradation, pointing to regulation at the transcriptional level, which is reversible upon amino-acid replacement. Strikingly, this downregulation was seen only with essential amino-acid deficiency and not nonessential amino acids. These data suggest that FTO might have a role in the sensing of essential amino-acid availability.

Service learning in medical and nursing training: a randomized controlled trial.

The purpose of this study was to explore the long term effect of a service learning project on medical and nursing students' knowledge in aging and their attitudes toward older adults. A total of 124 students were recruited and then randomized to intervention group (IG) and control group (CG). A pre-and-post-intervention design measured students' knowledge in aging (using modified Palmore's Fact on Aging Quiz) and attitudes toward older adults (using Kogan's Old People Scale). A total of 103 students completed all the activities and questionnaires. After the intervention, there were significant differences between the IG and CG on Palmore's mental health (MH) (P = .04), Palmore's total score (P = .02) and Kogan's negative attitudes toward older adults (P = .001). All students increased their positive attitude toward older adults after the intervention. However, both the IG and CG showed a decrease in positive attitudes 1 month after the interventon, and such decrease varied, depending on the programme which students attended. The current study showed that the 10-week service learning activities significantly increased medical and nursing students' overall knowledge of aging and their understanding of mental health needs in old age, and reduced their negative attitudes toward older adults. However, the effect is not long-lasting. On the other hand, its effect on positive attitudes toward older adults cannot be concluded. Periodic contacts with older adults via service learning activities may be needed to sustain attitude change toward older adults.

Molecular evidence for the Southern Hemisphere origin and deep-sea diversification of spiny lobsters (Crustacea: Decapoda: Palinuridae).

Spiny lobsters (family Palinuridae) are economically important marine animals that have been the subject of a considerable amount of research. However, the phylogeny of this group remains disputed. Morphological analyses have not been able to resolve the relationships of the various members of the group, and no agreement has yet been reached on its phylogeny as indicated by the different gene trees reported to date. In the present study, we attempt to reconstruct the phylogeny of Palinuridae and its allies using sequences from three nuclear protein-coding genes (phosphoenolpyruvate carboxykinase, sodium-potassium ATPase alpha-subunit and histone 3). The inferred topology receives strong nodal support for most of the branches. The family Palinuridae is found to be paraphyletic with the polyphyletic Synaxidae nested within it. Stridentes forms a monophyletic assemblage, indicating that the stridulating sound producing organ evolved only once in the spiny lobsters. By contrast, Silentes is paraphyletic, as Palinurellus is more closely related to Stridentes than to other Silentes genera. The three genera restricted to the southern high latitudes (Jasus, Projasus and Sagmariasus) constitute the basal lineages in the spiny lobsters, suggesting a Southern Hemisphere origin for the group. Subsequent diversification appears to have been driven by the closure of the Tethys Sea and the formation of the Antarctic circumpolar current, which isolated the northern and southern taxa. Contrary to an earlier hypothesis that postulated evolution from a deep-sea ancestral stock, the shallow-water genus Panulirus is the basal taxon in Stridentes, while the deep-sea genera Puerulus and Linuparus are found to be derived. This indicates that the spiny lobsters invaded deep-sea habitats from the shallower water rocky reefs and then radiated. Our results suggest that Synaxidae is not a valid family, and should be considered to be synonymous with Palinuridae. We also found that the previously proposed subgenera Sagmariasus and Nupalirus are genetically highly diverged, and both warrant a generic status.

Protein tightly bound near the termini of the Physarum extrachromosomal rDNA palindrome.

The genes coding for ribosomal RNa in plasmodia of Physarum polycephalum are arranged palindromically on extrachromosomal rDNA molecules of 61 kb (kilobasepairs). Incubation of mildly extracted rDNA with the 125I Bolton-Hunter reagent results in incorporation of label not removed by SDS, CsCl, or various organic solvents. Labeled protein is preferentially associated with terminal rDNA restriction fragments, as detected after gel electrophoresis of the DNA. Antibody reaction with dinitrophenylated protein-rDNA complexes allows visualization of protein located from 1 to 2 kb from the termini, in a region containing multiple inverted repeat sequences and single-strand gaps. DNase I treatment of either rDNA or rDNA termini releases primarily two labeled protein bands of 5,000 and 13,000 daltons as well as less prominent bands of higher molecular weight. We discuss mechanisms for involvement of terminal protein in replication of 3' ends and chromosomal integration of the rDNA.

Cross-reactive idiotypes in immunoglobulin A-deficient sera.

Mice of inbred strains immunized with simple antigens can produce antibodies that share similar V regions, which result in serologic similarities called cross-reactive idiotypes (CRI). In this study, we considered the possibility that IgA-deficient humans, who are continuously immunized via the intestinal tract by dietary protein, might also produce antibodies sharing CRI. For this, anti-casein antibodies were isolated from the blood of 16 adult IgA-deficient donors (4 Finns and 12 North Americans) and an autologous anti-anti-casein from the blood of one of the Finnish donors. In addition, a heterologous anti-anti-casein was raised to the casein-anti-casein immune complexes of this donor. Comparing the activities of the two anti-idiotypes, it was found that both bind anti-casein in the region of the antigen binding site, but that each binds additional determinants not located within this region, with the heterologous reagent having more affinity for these latter determinants than the autologous anti-idiotype. Using both reagents in enzyme-linked immunosorbent assay inhibition assays, extensive cross-reactivities between anti-caseins were demonstrated. Using the autologous anti-idiotype, 5 of 16 anti-caseins were found to share CRI, and with the heterologous reagent 12 of 16 shared CRI. In both assays, the anti-caseins of Finnish donors displayed more cross-reactivity than those derived from Northern American donors. These studies show that specific, commonly shared CRI can be identified in this human system in which antibodies are raised as a result of natural immunization across the gastrointestinal mucosa.

Modification of mitochondrial respiration by aging and dietary restriction.

Effects of aging and of dietary restriction on mitochondrial recovery and respiratory capacities have been assessed in mice. Old mice (23-26 months) did not differ from adult mice (9-12 months) in amounts of protein recovered in mitochondrial fractions of liver, brain and spleen, but did show a decline in specific activity of cytochrome c oxidase (cyt. c ox.) in liver and spleen. Age effects on in vitro respiration by mitochondria occurred in liver and spleen. In liver, only one substrate (beta-hydroxybutyrate) of four tested was respired at a different rate by old than by young mitochondria. Depression of state 3 respiration and 2,4-dinitrophenol (DNP)-uncoupled rates was observed for this substrate; however, this effect depended on expressing respiration on the basis of mitochondrial protein and was less overt if data were expressed per unit of cyt. c ox. activity. Old spleen mitochondria exhibited a grosser defect, showing a 40% decrease in the respiratory control index (RCI) for (succinate + rotenone)- supported respiration (the only substrate tested) due to a possible increase in state 4 rates. Effects of dietary restriction were assessed in liver and brain of 3-7-month-old mice underfed since weaning. Dietary restriction reduced recovery of total liver mitochondrial protein and liver cyt. c ox. specific activity. Liver mitochondria from restricted mice generally showed increased state 3 rates with no differences from controls in state 4 rates for respiration supported by glutamate or pyruvate + malate, resulting in an increased RCI for these substrates. DNP-uncoupled rates were also raised by dietary restriction. Unlike effects observed in old versus young mice, these differences obtained whether the data were expressed on the basis of mitochondrial protein or on cyt. c ox. activity. Electron microscopy of liver mitochondrial preparations revealed more non-mitochondrial contaminants in old mice and larger mitochondria in dietarily restricted mice. These findings are compatible with reports of age-dependent losses of liver mitochondria and suggest that dietary restriction may retard this loss.

Delayed phytohemagglutinin-stimulated production of adenosine triphosphate by aged human lymphocytes: possible relation to mitochondrial dysfunction.

The decreased immune response associated with aging may, in part, reflect intrinsic age-related biochemical alterations in lymphocytes from older animals. We measured levels of lymphocyte adenosine triphosphate (ATP) and continuous [3H]thymidine incorporation in phytohemagglutinin-stimulated lymphocytes from young and old humans, and the effects thereon of inhibitors of mitochondrial oxidative phosphorylation and protein synthesis. No difference was found in adenine nucleotide content between young and old subjects. After 24 hours of culture there was a decrease in ATP, with recovery and 2--3-fold increase at 48 hours in young cells after phytohemagglutinin stimulation. We observed a clearcut delay in older lymphocytes of the increase in ATP and [3H]thymidine incorporation following phytohemagglutinin stimulation. We found no evidence for decreased viability or diminished number of responding units in aged cultures. The evidence suggests that mitochondrial dysfunction may play a role in the immunodeficiency of aging.

The role of nitric oxide in uveitis.

OBJECTIVE: To evaluate the possible role played by nitric oxide in the pathogenesis of uveitis. METHODS: Uveitis was induced in rats with subcutaneous lipopolysaccharide. Lipopolysaccharide stimulates nitric oxide production from L-arginine. The animals were treated with NG-nitro-L-arginine methyl ester, an L-arginine analogue acting as a specific inhibitor of nitric oxide synthesis. Ocular inflammation was evaluated by measuring protein concentration and leukocyte number in the aqueous humor of one eye, and by histopathologic examination of the contralateral eye. RESULTS: Aqueous humor protein levels were reduced 73% to 82% and cellular infiltration was almost abrogated in NG-nitro-L-arginine methyl ester-treated rats compared with controls. The histopathologic examination also showed a similar inhibition of uveal tissue inflammation in treated rats. CONCLUSION: By inhibiting nitric oxide synthesis, NG-nitro-L-arginine methyl ester inhibits the induction of endotoxin-induced uveitis in the rat. This observation demonstrates that nitric oxide is an important mediator of anterior uveitis in this model system and suggests that nitric oxide may also be implicated in human uveitis.

The specificity of glutamate inhibition of protein synthesis in synaptosomal fractions from rat cerebral cortex.

In vitro addition of glutamate (GLU) resulted in a dose-dependent inhibition of protein synthesis in synaptosomes from adult rat brain cortex. There was significant (20-25%) inhibition at 25 ?M GLU and a maximum (30-50%) inhibition was observed at [GLU] ? 200 ?M. The excitatory amino acids, N- methyl- d -aspartic acid (NMDA), kainic acid (KA), quinolinic acid (QUIN) and selected non-excitatory amino acids did not markedly inhibit protein synthesis at all concentrations tested. On the other hand, aspartic acid (ASP), ibotenic acid (IBO), quisqualic acid (QA) and ?-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) produced a significant but apparently less potent inhibition than GLU. In the presence of AMPA plus ASP or GLU (500 ?M each), protein synthesis inhibition was equivalent to the maximum effect of GLU alone. However, only partial additive effects were observed with high concentrations of AMPA + IBO or AMPA + QA. In the presence of 200 ?M ouabain, synergistic GLU inhibition was not observed suggesting that GLU specifically inhibited the sodium-dependent, ouabain-sensitive component of synaptosomal protein synthesis. The inhibitory action of GLU is not dependent on externally added Ca(2+) or Cl(?). Supplementation with 5 mM MgCl(2) or 1.0 mM GLU antagonists, 2-amino-5-phosphonovaleric acid (AP5), 2-amino-7-phosphonoheptanoic acid (AP7), ?-glutamylglycine (?-DGG), kynurenic acid (KYN), MK-801, l-glutamic acid diethyl ester (GDEE) and 6-cyano-7-nitro quinoxaline-2,3-dione (CNQX) did not protect the synaptosomes from 50 ?M GLU. Inhibiting glutamate uptake or phosphoinositide metabolism with 1 mM dihydrokainic acid (DHK) and 5 mM LiCl(2), respectively, was also non-protective. These data suggest that GLU and other excitatory amino acids (EAA) specifically inhibit synaptosomal protein synthesis. The inhibitory effect is partially associated with activation of QA-preferring receptors which may not be coupled to phosphoinositide metabolism. A possible candidate might be the AMPA specific QA receptor located in the postsynaptic density which is in close proximity to rosettes of polyribosomes. In addition, there is a GLU-sensitive, QA-resistant component of synaptosome protein synthesis which does not appear to be dependent on activation of any of the known pharmacologically defined GLU receptor subtypes.

Diagnosis of reactive lymphoid hyperplasia by chorioretinal biopsy.

We treated a patient with reactive lymphoid hyperplasia in whom the diagnosis was made by chorioretinal biopsy. Histopathologic examination and culture of the biopsied specimen allowed us to rule out a neoplastic or infectious process. The biopsy result allowed us to treat him with systemic corticosteroid alone, thus avoiding the potential harmful side effects of other medications, including antituberculous drugs. There were no surgical or postoperative complications. This study confirms the usefulness of chorioretinal biopsy for establishing a diagnosis and formulating a rational treatment plan.

Protective role of nitric oxide in ocular toxoplasmosis.

AIMS: To evaluate the role of nitric oxide (NO) in ocular involvement during systemic toxoplasmosis. METHODS: C57B1/6 mice were infected with Toxoplasma gondii strain ME49. The synthesis of NO was inhibited by an intraperitoneal injection of aminoguanidine every 8 hours, starting on the day of infection. Control infected mice received phosphate buffered saline vehicle alone. After 14 days, the ocular lesions were evaluated by histopathological examination. The expression of NO synthase induced in the spleen by toxoplasma infection was evaluated by immunostaining. The production of NO by the spleen cells of infected mice was measured by the colorimetric assay of Griess in the supernatant of cultures stimulated with toxoplasma antigen or concanavalin A. RESULTS: The inhibition of NO production in T gondii infected mice resulted in a marked increase in the symptoms of ocular inflammation. We observed a strong induction of NO synthase expression in the spleen of infected animals. In culture, the spleen cells from these mice produced high levels of NO in response to T gondii antigens. This elevation of NO synthesis was suppressed in the presence of aminoguanidine. CONCLUSION: This study indicates that NO plays a crucial role in the protection against T gondii infection as reflected by the severity of the ocular involvement.

Clinical pathologic findings of Propionibacterium acnes endophthalmitis.

The autors presented two typical cases of patients who were infected with Propionibacterium acnes (P. acnes) after intraocular lens implantation. The patients were treated successfully by the removal of the intraocular lens and the residual lens capsule, and the administration of intravitreal vacomycin. The histopathology illustrated numerous prokaryote bacilli surrounding the lens material without inflammatory reaction. The thickened bacterial cell wall structure may relate to the resistance of P. acnes killing and degradation by the host neutrophils and macrophages. Complete removal of the lens material which may sequester the bacterial growth in the eye is important to eradicate P. acnes endophthalmitis.

Fighting outbreaks with bacterial genomics: case review and workflow proposal.

BACKGROUND: Disease outbreak investigation is a key aspect of public health. Whole-genome sequencing of bacterial pathogen based on new generation high-throughput sequencing technologies has facilitated outbreak investigations recently. Whilst the approach has become more affordable and accessible to research and clinical laboratories, a system for adequate and efficient analyses of genome data in the context of bacterial outbreak investigations is missing. METHODS: We performed a literature review of timely genomic investigations performed during the course of bacterial outbreaks that are based on new generation sequencing technologies. Currently available bioinformatics tools for genomic analyses are also reviewed here. RESULTS: Genomic investigations in early stages of bacterial outbreaks have shown to provide timely information on evolutionary origin, transmission route, pathogenic potential, and resistance information of the outbreak strains and allow development of strain-specific typing methods. A systematic genomic analytical workflow is proposed here for the first time to facilitate efficient extraction of epidemiologically useful information from genome data of bacterial pathogens in future bacterial outbreak investigations. CONCLUSION: With the continuous reduction of genome sequencing cost and development of user-friendly analytical tools, it is expected that high-throughput genome sequencing will be applied routinely for timely genomic analysis in bacterial outbreaks in the near future.

Where to go with FTO?

An understanding of the mechanisms underlying body-weight regulation is crucial to tackle the growing problem of obesity. Recent technological advances in the analysis of genetic variation have given novel insights into the molecular basis of common disease. In particular, genomic variants in the fat mass and obesity-associated (FTO) gene have been consistently associated with human adiposity and metabolic disorders. Studies of the product of this previously mysterious gene have formed a vanguard in the quest to turn statistical association into hard biology. In this review, we examine data from human genetic and murine studies that explore the potential role of FTO, a member of the Fe(II)- and 2-oxoglutarate-dependent oxygenase superfamily, in the regulation of energy homeostasis and metabolism.

The impact of the absolute number and ratio of positive lymph nodes on survival of endometrioid uterine cancer patients.

The aim of the study was to determine the impact of the absolute number and ratio of positive lymph nodes on the survival in node-positive endometrioid uterine cancer. Data were obtained from the National Cancer Institute Registry from 1988 to 2001. Analyses were performed using Kaplan-Meier and Cox proportional hazard methods. A total of 1222 women were diagnosed with stage IIIC-IV node-positive endometrioid corpus cancer. The 5-year disease-specific survival of women with 1, 2-5, and >5 positive nodes were 68.1, 55.1, and 46.1%, respectively (P<0.001). Increasing lymph node ratio, expressed as a percentage of positive nodes to total nodes identified (10-50%), was associated with a decrease in survival from 77.3 to 60.7 to 40.9%, respectively (P<0.001). The absolute number of positive nodes and the lymph node ratio remained significant after adjusting for stage (IIIC vs IV) and the extent of lymphadenectomy (20 nodes). On multivariate analysis, the absolute number of positive nodes and lymph node ratio were significant independent prognostic factors for survival. Increasing absolute number of positive nodes and lymph node ratio are associated with a poorer survival in women with node-positive uterine cancers. The stratification of node-positive uterine cancer for prognostic and treatment purposes warrants further investigation.

Ovarian cancer in younger vs older women: a population-based analysis.

To compare the clinico-pathologic prognostic factors and survival of younger vs older women diagnosed with epithelial ovarian cancer. Demographic, clinico-pathologic, treatment, and surgery information were obtained from patients with ovarian cancer from the Surveillance, Epidemiology, and End Results Program from 1988 to 2001 and analysed using Kaplan-Meier estimates. Of 28 165 patients, 400 were <30 years (very young), 11 601 were 30-60 (young), and 16 164 were >60 (older) years of age. Of the very young, young, and older patients, 261 (65.3%), 4664 (40.2%), and 3643 (22.5%) had stage I-II disease, respectively (P<0.001). Across all stages, very young women had a significant survival advantage over the young and older groups with 5-year disease-specific survival estimates at 78.8% vs 58.8 and 35.3%, respectively (P<0.001). This survival difference between the age groups persists even after adjusting for race, stage, grade, and surgical treatment. Reproductive age (16-40 years) women with stage I-II epithelial ovarian cancer who received uterine-sparing procedures had similar survivals compared to those who underwent standard surgery (93.3% vs 91.5%, P=0.26). Younger women with epithelial ovarian cancer have a survival advantage compared to older patients.