Neural and hormonal control of food hoarding.

Many animals hoard food, including humans, but despite its pervasiveness, little is known about the physiological mechanisms underlying this appetitive behavior. We summarize studies of food hoarding in humans and rodents with an emphasis on mechanistic laboratory studies of species where this behavior importantly impacts their energy balance (hamsters), but include laboratory rat studies although their wild counterparts do not hoard food. The photoperiod and cold can affect food hoarding, but food availability is the most significant environmental factor affecting food hoarding. Food-deprived/restricted hamsters and humans exhibit large increases in food hoarding compared with their fed counterparts, both doing so without overeating. Some of the peripheral and central peptides involved in food intake also affect food hoarding, although many have not been tested. Ad libitum-fed hamsters given systemic injections of ghrelin, the peripheral orexigenic hormone that increases with fasting, mimics food deprivation-induced increases in food hoarding. Neuropeptide Y or agouti-related protein, brain peptides stimulated by ghrelin, given centrally to ad libitum-fed hamsters, duplicates the early and prolonged postfood deprivation increases in food hoarding, whereas central melanocortin receptor agonism tends to inhibit food deprivation and ghrelin stimulation of hoarding. Central or peripheral leptin injection or peripheral cholecystokinin-33, known satiety peptides, inhibit food hoarding. Food hoarding markedly increases with pregnancy and lactation. Because fasted and/or obese humans hoard more food in general, and more high-density/high-fat foods specifically, than nonfasted and/or nonobese humans, understanding the mechanisms underlying food hoarding could provide another target for behavioral/pharmacological approaches to curb obesity.

A virtual reality simulator for teaching and evaluating dental procedures.

OBJECTIVES: We present a dental training system with a haptic interface that allows dental students or experts to practice dental procedures in a virtual environment. The simulator is able to monitor and classify the performance of an operator into novice or expert categories. The intelligent training module allows a student to simultaneously and proactively follow the correct dental procedures demonstrated by an intelligent tutor. METHODS: The virtual reality (VR) simulator simulates the tooth preparation procedure both graphically and haptically, using a video display and haptic device. We evaluated the performance of users using hidden Markov models (HMMs) incorporating various data collected by the simulator. We implemented an intelligent training module which is able to record and replay the procedure that was performed by an expert and allows students to follow the correct steps and apply force proactively by themselves while reproducing the procedure. RESULTS: We find that the level of graphics and haptics fidelity is acceptable as evaluated by dentists. The accuracy of the objective performance assessment using HMMs is encouraging with 100 percent accuracy. CONCLUSIONS: The simulator can simulate realistic tooth surface exploration and cutting. The accuracy of automatic performance assessment system using HMMs is also acceptable on relatively small data sets. The intelligent training allows skill transfer in a proactive manner which is an advantage over the passive method in a traditional training. We will soon conduct experiments with more participants and implement a variety of training strategies.

Prevalence and pathology of lungworm infection in bottlenose dolphins Tursiops truncatus from southwest Florida.

Parasitism of the respiratory system is a relatively common finding in stranded cetaceans; however, no systematic investigations regarding the severity, distribution, and clinical consequences of these infections in bottlenose dolphins Tursiops truncatus have been conducted previously. The present study determined the prevalence of lungworm infections in dead stranded (n=22) and live bottlenose dolphins (n=44) from southwestern Florida, USA, during the period from 2003 to 2005. Dead stranded bottlenose dolphins were necropsied and lungs were examined visually, by palpation, and histologically for lesions consistent with verminous pneumonia. When present, nematodes were counted, measured, and identified to species based upon their morphology. Dolphin feces and blowhole swabs were collected and examined for nematode larvae. Lungworm prevalence was 77% in dead animals (n=22). The lesions in most cases were mild, chronic, and not the primary cause of death. Only 13% of dead animals examined had patent infections, with larvae present in blowhole and fecal cytology, and only 18% of animals had intact worms present at necropsy, with a geometric mean intensity of infection of 22.6 worms animal(-1). Intact worms were identified as either Halocercus lagenorhynchi or Skrjabinalius cryptocephalus. The highest prevalence of active infections was found in neonates and calves, including 1 stillborn calf. For free-ranging animals, all blowhole swabs (n=44) were negative, and fecal cytology (n=22) showed a 3% prevalence of patent infection. Findings from the present study support the theory that bottlenose dolphins can be infected transplacentally by lungworms. The impact that such infections may have on neonatal survival is unknown; however, these infections could increase neonatal mortality.

First report and characterization of adult Uncinaria spp. in New Zealand Sea Lion (Phocarctos hookeri) pups from the Auckland Islands, New Zealand.

Two species of hookworms (Uncinaria lucasi and Uncinaria hamiltoni) have been formally described from pinnipeds, but dissimilar types are noted from these hosts. This report is the first description of hookworms (Uncinaria spp.) from the New Zealand sea lion, Phocarctos hookeri. The nematodes were collected from dead pups on Enderby Island (Auckland Islands, 50 degrees 30', 166 degrees 17') during January and February, 2004. Standard measurements of male and female hookworms were obtained, providing a general morphometric characterization of the hookworm species in P. hookeri. Considerable variations in the body length of adult hookworms were noted within the same host. The arrangement of some of the bursal rays differs from that described for U. lucasi and U. hamiltoni.

First report of parasites from pinnipeds in the Galapagos Islands, Ecuador, with a description of a new species of Philophthalmus (Digenea: Philophthalmidae).

A new species of digenetic trematode and 2 species of ectoparasites from Zalophus wollebaeki Silvertsen, 1953 (Carnivora: Otariidae) in the Galapagos Islands, Ecuador, are reported. These include an eye fluke of Philophthalmus Looss, 1899 (Echinostomata: Philophthalmidae) as well as, to our knowledge, the first report of Antarctophthirus microchir (Trouessart and Neumann, 1888) Enderlein, 1906 (Arthropoda: Anoplura) and Orthohalarachne diminuata (Doetschman, 1944) Newell, 1947 (Arthropoda: Acarina) from this host and location. Philophthalmus zalophi n. sp. differs from the 4 other marine species of Philophthalmus (P. andersoni Dronen and Penner, 1975; P. burrili Howell and Bearup, 1967; P. hegeneri Penner and Fried, 1963; and P. larsoni Penner and Trimble, 1970) by its mammalian host, large body size, lack of tegumental spines, posterior length of seminal vesicle, placement of genital pore, size ratio of oral sucker to acetabulum, shape and size of testes, and size ratio of ovary to testis.

Comparative biochemical analyses of venous blood and peritoneal fluid from horses with colic using a portable analyser and an in-house analyser.

Fifty-six horses with colic were examined over a period of three months. The concentrations of glucose, lactate, sodium, potassium and chloride, and the pH of samples of blood and peritoneal fluid, were determined with a portable clinical analyser and with an in-house analyser and the results were compared. Compared with the in-house analyser, the portable analyser gave higher pH values for blood and peritoneal fluid with greater variability in the alkaline range, and lower pH values in the acidic range, lower concentrations of glucose in the range below 8.3 mmol/l, and lower concentrations of lactate in venous blood in the range below 5 mmol/l and in peritoneal fluid in the range below 2 mmol/l, with less variability. On average, the portable analyser underestimated the concentrations of lactate and glucose in peritoneal fluid in comparison with the in-house analyser. Its measurements of the concentrations of sodium and chloride in peritoneal fluid had a higher bias and were more variable than the measurements in venous blood, and its measurements of potassium in venous blood and peritoneal fluid had a smaller bias and less variability than the measurements made with the in-house analyser.

Anger and acne: implications for quality of life, patient satisfaction and clinical care.

BACKGROUND: Acne is a common skin disorder with a significant psychological and social impact for some people. Little is known about how personality and emotional traits affect acne and its impact on quality of life and treatment. Trait anger (TA), which is related to heart disease and other morbidities, may also affect acne and patients' adjustment to it. OBJECTIVES: To evaluate the relationship between TA and acne severity, skin-related quality of life, satisfaction with treatment, and adherence to treatment. PARTICIPANTS AND METHODS: A sample of 479 individuals with acne completed a survey instrument to assess acne severity, skin care practices, skin-related quality of life, satisfaction with treatment, adherence, TA and demographic variables. Respondents who reported high TA were compared with individuals with low TA on outcome variables. Regression analyses adjusted for covariates and identified the significant predictors of quality of life, satisfaction and adherence. RESULTS: High TA was unrelated to acne severity (P = 0.2) or frequency of face washing (P = 0.9). Anger was significantly related to both global quality of life (P < 0.001) and skin-related quality of life (P = 0.002) as well as to satisfaction with treatment (P = 0.001) and adherence to treatment advice (P = 0.05) in bivariate analyses. Regression analyses revealed that high TA remained a significant predictor of global (P < 0.001) and skin-related quality of life (P = 0.003) and satisfaction with treatment (P = 0.04), but not adherence to treatment advice (P = 0.8) after controlling for covariates. CONCLUSIONS: Anger is associated with the quality of patients' lives and with their satisfaction with treatment. Care of acne patients should include attention to anger and other chronic emotional states, quality of life, as well as to clinical severity. Simple guidelines are suggested for how clinicians might approach this important aspect of care.

Redescription of Serpinema octorugatum (Baylis, 1933) nematoda: Camallanidae from the Malayan box turtle Cuora amboinensis Daudin Chelonia: Bataguridae.

We redescribe the camallanid nematode Serpinema octorugatum (Baylis, 1933) from the box turtle Cuora amboinensis (Daudin) collected in Malaysia. In this redescription, we amend the original description by noting that there are only four cephalic papillae and that there are five pairs of post-anal papillae, and propose that the name of this species be corrected from S. octorugatus to S. octorugatum. Additionally, we removed the tissues overlying the buccal capsule and have used SEM studies to show that the peribuccal shields extend laterally from the buccal capsule, forming a surface possibly used in muscle attachment. Furthermore, we show that the supposedly non-cuticularised cylinder connecting the buccal capsule to the oesophagus in the Camallanidae is part of the buccal capsule and is, therefore, likely to be cuticularised. We also examine morphological measurements of taxonomic interest for correlations with total body length and find that many characters traditionally used for inter- and intra-specific comparisons are correlated with total body length in adult female worms. This suggests that comparisons between samples of adult female worms that do not account for the potential effect of total body length may be misleading. However, we show that some features of taxonomic interest are not correlated with total body length.

Correlative microscopy of cerebellar Bergmann glial cells.

Double fluorescent labelling of rat cerebellar cortex using antibody to glial fibrillary acidic protein (GFAP) and Alexa fluor conjugates for secondary detection for confocal laser scanning microscope (CLSM), field emission scanning electron microscopy (FESEM) of Rhesus monkey cerebellar cortex, ultrathin sectioning and freeze-etching replica method for transmission electron microscopy of mouse cerebellar cortex have been examined in an attempt to obtain a new and more accurate view of three-dimensional image of Bergmann glial cells (BGC) and their topographic relations in the molecular layer. Intense immunopositive GFAP green staining was observed in the BGC and glial limiting layer. Secondary antibody conjugated with Alexa fluor 488 and Alexa fluor 668-1B4 stained in red capillary endothelial cells and microglial cells. BGC morphology revealed the existence of several cell types or subpopulations of BGC. Bergmann glial fibers, in palisade arrangement, branch and rebranch forming a complex glial network in the molecular layer. Field emission SEM and freeze-fracture SEM method show the SE-I image of high mass dense Bergmann glial cytoplasm ensheathing like a veil the Purkinje cell (PC) soma and dendritric arborization. Bergmann glial fibers appeared completely surrounding individual parallel fibers or parallel fiber bundles, terminal climbing fiber collaterals, basket and stellate cells and capillaries. Freeze-etching direct replicas showed the typical orthogonal arrangement of intramembrane particles, corresponding to the large repertoire of BGC receptors. The study reveals three-dimensional Bergmann glial cells heterogeneity and the complex network formed by Bergmann glial cells in the molecular layer.

A common oocyst surface antigen of Cryptosporidium recognized by monoclonal antibodies.

Two hybridoma clones, CMYL3 and CMYL30, were generated by immunizing Balb/c mice with excysted oocysts of Cryptosporidium muris. Both clones secreted monoclonal antibodies against an oocyst-wall antigen with apparent molecular mass of 250 kDa (called CM250) from C. muris and C. parvum. The epitope appeared to be periodate-sensitive, suggesting the involvement of a carbohydrate moiety. Immunofluorescence and confocal microscopy on purified oocysts and infected mouse tissues revealed staining confined to the oocyst wall of both Cryptosporidium species. Immunogold labeling further revealed the presence of the CM250 antigen in electron-dense vesicles and cytoplasm of developing macrogametocytes, and ultimately localized to the oocyst wall of mature oocysts. Both antibodies cross-reacted with C. serpentis oocysts but did not recognize the other enteropathogenic protozoans Giardia muris, Eimeria falciformis and E. nischulz. These antibodies may be valuable tools for the analysis of oocyst-wall formation in Cryptosporidium and characterization of the common antigen.

Hippocampal mossy fibers induce assembly and clustering of PSD95-containing postsynaptic densities independent of glutamate receptor activation.

Factors that regulate the formation, spatial patterning, and maturation of CNS synapses are poorly understood. We used organotypic hippocampal slice cultures derived from developing (P5-P7) rat to test whether synaptic activity regulates the development and organization of postsynaptic structures at mossy fiber (MF) giant synapses. Antibodies to a prominent postsynaptic density (PSD) scaffold protein, PSD95, identified large (>1 microm) and irregularly shaped PSD assemblies that codistributed with synapsin-I or metabotropic glutamate receptor 7b (mGluR7b) -immunolabeled MF terminals in area CA3. To investigate the spatial organization of synaptic PSDs on individual pyramidal cells, neurons in slice cultures were transfected with a vector encoding a GFP-PSD95 fusion protein. Confocal three-dimensional reconstructions revealed clusters of PSDs along proximal dendrites of transfected pyramidal neurons in area CA3, but not in CA1. Clusters averaged 7.6 microm in length (range, 2.2-29 microm) and contained up to 35 individual PSDs (mean, 8.3). PSD clusters failed to form when slices were cultured without MFs, indicating that MFs induce cluster assembly. Chronic blockade of N-methyl-D-apartate- and AMPA/kainate-type glutamate receptors did not disrupt MF targeting or de novo formation of PSD clusters with a normal distribution on target cells. Additionally, glutamate receptor blockers did not alter the ultrastructural development of MF giant synapses containing multiple puncta adherens-like junctions and asymmetric synaptic junctions at dendritic shaft and spine domains, respectively. The results indicate that MF axons can induce the assembly and clustering of PSD95-containing postsynaptic complexes, displaying a normal subcellular and tissue distribution, by mechanisms that are independent of ionotropic glutamate receptor activation.

Rapid formation and remodeling of postsynaptic densities in developing dendrites.

The dynamics of postsynaptic density (PSD) formation and remodeling were investigated in live developing hippocampal tissue slices. Time lapse imaging of transfected neurons expressing GFP-tagged PSD95, a prominent PSD protein, revealed that up to 40% of PSDs in developing dendrites are structurally dynamic; they rapidly (<15 min) appear or disappear, but also grow, shrink and move within shafts and spines. New spines containing PSDs were formed by conversion of dynamic filopodia-like spine precursors in which PSDs appeared de novo, or by direct extension of spines or spine precursors carrying preformed PSDs from the shaft. PSDs are therefore highly dynamic structures that can undergo rapid structural alteration within dendrite shafts, spines and spine precursors, permitting rapid formation and remodeling of synaptic connections in developing CNS tissues.

Surrogate consent by family members for out-of-hospital cardiac arrest research.

OBJECTIVES: To evaluate the availability of family members of potential subjects to provide consent for participation in out-of-hospital cardiac arrest (OOHCA) research and to estimate the time required to contact a family member. METHODS: This study was a prospective observational study of adult patients (>18 years old) with nontraumatic OOHCA treated by an urban emergency medical service. Emergency medicine resident physicians responded to each scene and noted the presence of family members. A subsequent convenience sample of family members answered standardized questions about their ability to provide consent for research participation on behalf of the patient. RESULTS: Physicians were present at 100 of the 112 adult medical cardiac arrests during the study period. A family member was present at 57% of the scenes (95% CI = 47% to 67%). Patients with family present were older and were less likely to have bystander cardiopulmonary resuscitation (CPR) or live in a nursing home. The mean time (+/-SE) from emergency dispatch to family contact was 24.40 (+/-2.60) minutes and from physician arrival to family contact was 2.45 (+/-0.87) minutes (n = 20). Eight of 13 family members were willing to enroll the patient into a resuscitation study, but five family members were unable to understand the explanation of informed consent. CONCLUSIONS: Family members were present for an unrepresentative subset of OOHCA cases, and were contacted after the therapeutic window for many interventions. The emotional nature of the emergency situation also limited the reliability of surrogate consent for OOHCA research.

Regulation of membrane metalloproteolytic cleavage of L-selectin (CD62l) by the epidermal growth factor domain.

The adhesion molecule L-selectin is cleaved rapidly from the surface of activated leukocytes by tumor necrosis factor-alpha converting enzyme, a cell surface metalloprotease, and also undergoes slower constitutive shedding in unactivated cells. The structural features that render it susceptible to shedding are poorly understood. We therefore analyzed the shedding of a series of mutant and chimeric L-selectin molecules. Although murine L-selectin is cleaved at a specific location in the juxtamembrane region 11 amino acids distal to the cell membrane, this cleavage has little sequence specificity. However, proline substitution at the P2' or P3' position or deletion of the epidermal growth factor (EGF) domain completely blocks the rapid phorbol ester-induced cleavage, but does not affect the slower basal proteolytic shedding. Insertion of the 15-residue membrane-proximal region (MPR) of L-selectin into the heterologous protein B7.2 results in a molecule that undergoes constitutive proteolytic turnover. In contrast, insertion of both the EGF domain and the MPR confers susceptibility to both slow constitutive shedding and the rapid proteolytic cleavage induced by phorbol 12-myristate 13-acetate. These results demonstrate that constitutive and induced L-selectin cleavage are separable processes and that the rapid phorbol ester-induced shedding requires the presence of the EGF domain, a sequence that is remote from the cleavage site.

Dynamics of microglial activation: a confocal time-lapse analysis in hippocampal slices.

The dynamics of microglial cell activation was studied in freshly prepared rat brain tissue slices. Microglia became activated in the tissue slices, as evidenced by their conversion from a ramified to amoeboid form within several hours in vitro. To define better the cytoarchitectural dynamics underlying microglial activation, we performed direct three-dimensional time-lapse confocal imaging of microglial cells in live brain slices. Microglia in tissue slices were stained with a fluorescent lectin conjugate, FITC-IB(4), and stacks of confocal optical sections through the tissue were collected repeatedly at intervals of 2-5 min for several hours at a time. Morphometric analysis of cells from time-lapse sequences revealed that ramified microglia progress to amoeboid macrophages through a stereotypical sequence of steps. First, in the withdrawal stage, the existing ramified branches of activating microglia do not actively extend or engulf other cells, but instead retract back (mean rate, 0.5-1.5 microm/min) and are completely resorbed into the cell body. Second, in the motility stage, a new set of dynamic protrusions, which can exhibit cycles of rapid extension and retraction (both up to 4 microm/min), abruptly emerges. Sometimes new processes begin to emerge even before the old branches are completely withdrawn. Third, in the locomotory stage, microglia begin translocating within the tissue (up to 118 microm/h) only after the new protrusions emerge. We conclude that the rapid conversion of resting ramified microglia to active amoeboid macrophages is accomplished not by converting quiescent branches to dynamic ones, but rather by replacing existing branches with an entirely new set of highly motile protrusions. This suggests that the ramified branches of resting microglia are normally incapable of rapid morphological dynamics necessary for activated microglial function. More generally, our time-lapse observations identify changes in the dynamic behavior of activating microglia and thereby help define distinct temporal and functional stages of activation for further investigation.

Characterization of the rapid proteolytic shedding of murine L-selectin.

The structural requirements for L-selectin shedding were studied in murine leukocytes. Upon activation, L-selectin on both lymphocytes and neutrophils undergoes cleavage by a membrane metalloprotease, resulting in the generation of a soluble ectodomain and a membrane-retained 6 kD fragment. Radiochemical sequencing demonstrated a cleavage site in the membrane-proximal region (MPR) between R321 and S322, which is homologous to the human site. Although intact neutrophil L-selectin is larger, it is cleaved at the same, or very close, site. Analysis of several transfectants expressing L-selectin point mutations and chimeric constructs suggest that, like human shedding, the proteolytic process has relatively loose sequence specificity for the substrate site. In addition, some constructs are susceptible to slow constitutive cleavage, but their shedding does not increase upon PMA stimulation, showing that basal and activated shedding are separable processes. Insertion of the 15 amino acid MPR into murine B7.2 conferred upon this molecule susceptibility to constitutive shedding. PMA stimulation results in little or no acceleration of down regulation of this molecule. These results suggest that recognition of both the membrane-proximal cleavage site and of a site distant from the MPR are required for maximal induction of L-selectin shedding.

Prey, parasites and pathology associated with the mortality of a juvenile gray whale (Eschrichtius robustus) stranded along the northern California coast.

An eastern Pacific gray whale (Eschrichtius robustus) stranded off Pelican Point, Tomales Bay, California, USA, was examined for physiological parameters, prey, parasites and associated pathology. The whale was emaciated, and hematological examination revealed an elevation in hematocrit, serum sodium, potassium, electrolyte values and hypoglycemia. Parasites recovered included 5 species, 1 ectoparasite (Cyamus scammoni), and 4 helminths (Anisakis simplex, Ogmogaster antarcticus, Ogmogaster pentalineatus, Bolbosoma balanae) with the latter causing multifocal transmural abscesses. Histological examination indicated severe acute lung congestion, minimal, multifocal, lymphocytic, interstitial myocarditis, and mild hepatocellular and Kupffer cell hemosiderosis. The prey taxa present in the stomach indicated the whale was feeding on hard bottom communities prior to death.

Cost-effectiveness of aerobic and resistance exercise in seniors with knee osteoarthritis.

PURPOSE: The purpose of this study was to determine, in a randomized clinical trial of 439 individuals with knee osteoarthritis, the incremental cost-effectiveness of aerobic versus weight resistance training, compared with an education control intervention. METHODS: Cost estimates of the intervention were based upon the cost of purchasing from the community similar services to provide exercise or health education. Effect at 18 months was measured using several variables, including: self-reported disability score, 6-min walking distance, stair climb, lifting and carrying task, car task, and measures of pain frequency and pain intensity on ambulation and transfer. RESULTS: The total cost of the educational intervention was $343.98 per participant. The aerobic exercise intervention cost $323.55 per participant, and the resistance training intervention cost $325.20 per participant. On all but two of the outcome variables, the incremental savings per incremental effect for the resistance exercise group was greater than for the aerobic exercise group. CONCLUSION: The data obtained from this study suggest that, compared with an education control, resistance training for seniors with knee osteoarthritis is more economically efficient than aerobic exercise in improving physical function. However, the magnitude of the difference in efficiency between the two approaches is small.

Reduce costs and improve patient satisfaction with home pre-operative bowel preparations.

The results of a home-based preoperative bowel preparation, with and without the support of home care services, are compared with hospital-based preoperative bowel preparation. Length of stay, morbidity, and mortality rates; issues of patient satisfaction; and demographics are reported. The method and tools used in planning, implementing, and evaluating the home preoperative bowel preparation program are also shared. Other issues discussed are the healthcare market forces that promote an increased value of care. Economic and patient satisfaction considerations by employers, payers, and patients; the increasing influence of patient choice on healthcare provider selection and care setting preferences; the nursing workforce issues related to the impending shortage; and issues of regulatory and accrediting agencies are also discussed.