Looking at the bid picture: A framework for identifying reverse auctions in ecological systems.

Biological market theory can be used to explain intraspecific cooperation, interspecific mutualism, and sexual selection through models of game theory. These models describe the interactions between organisms as two classes of traders (buyers/sellers) exchanging commodities in the form of goods (e.g. food, shelter, matings) and services (e.g. warning calls, protection). Here, we expand biological market theory to include auction theory where bidding serves to match buyers and sellers. In a reverse auction, the seller increases the value of the item or decreases the cost until a buyer steps forward. We provide several examples of ecological systems that may have reverse auctions as underlying mechanisms to form mutualistic relationships. We focus on the yellow baboon (Papio cynocephalus) mating system as a case study to propose how the mechanisms of a reverse auction, which have the unintended but emergent consequence of producing a mutually beneficial outcome that improves collective reproductive benefits of the troop in this multi-female multi-male polygynandrous social system. For the yellow baboon, we posit that the "seller" is the reproductively cycling female, and the "buyer" is a male looking to mate with a cycling female. To the male, the "item for the sale" is the opportunity to sire an offspring, the price is providing safety and foraging time (via consortship) to the female. The "increasing value of the item for sale" is the chance of conception, which increases with each cycle since a female has resumed cycling post-partum. The female's sexual swelling is an honest indicator of that cycle's probability of conception, and since resident males can track a female's cycle since resumption, there is transparency. The males presumably know the chance of conception when choosing to bid by offering consortship. Across nature, this reverse auction game likely exists in other inter- and intraspecific social relationships. Considering an ecological system as a reverse auction broadens our view of social evolution and adaptations through the lens of human economic structures.

Vagus nerve stimulation in the non-human primate: implantation methodology, characterization of nerve anatomy, target engagement and experimental applications.

BACKGROUND: Vagus nerve stimulation (VNS) is a FDA approved therapy regularly used to treat a variety of neurological disorders that impact the central nervous system (CNS) including epilepsy and stroke. Putatively, the therapeutic efficacy of VNS results from its action on neuromodulatory centers via projections of the vagus nerve to the solitary tract nucleus. Currently, there is not an established large animal model that facilitates detailed mechanistic studies exploring how VNS impacts the function of the CNS, especially during complex behaviors requiring motor action and decision making. METHODS: We describe the anatomical organization, surgical methodology to implant VNS electrodes on the left gagus nerve and characterization of target engagement/neural interface properties in a non-human primate (NHP) model of VNS that permits chronic stimulation over long periods of time. Furthermore, we describe the results of pilot experiments in a small number of NHPs to demonstrate how this preparation might be used in an animal model capable of performing complex motor and decision making tasks. RESULTS: VNS electrode impedance remained constant over months suggesting a stable interface. VNS elicited robust activation of the vagus nerve which resulted in decreases of respiration rate and/or partial pressure of carbon dioxide in expired air, but not changes in heart rate in both awake and anesthetized NHPs. CONCLUSIONS: We anticipate that this preparation will be very useful to study the mechanisms underlying the effects of VNS for the treatment of conditions such as epilepsy and depression, for which VNS is extensively used, as well as for the study of the neurobiological basis underlying higher order functions such as learning and memory.

Unstable population dynamics in obligate co-operators.

Cooperation significantly impacts a species' population dynamics as individuals choose others to associate with based upon fitness opportunities. Models of these dynamics typically assume that individuals can freely move between groups. Such an assumption works well for facultative co-operators (e.g. flocking birds, schooling fish, and swarming locusts) but less so for obligate co-operators (e.g. canids, cetaceans, and primates). With obligate co-operators, the fitness consequences from associations are stronger compared to facultative co-operators. Consequently, individuals within a group should be more discerning and selective over their associations, rejecting new members and even removing current members. Incorporating such aspects into population models may better reflect obligately cooperative species. In this paper, we create and analyze a model of the population dynamics of obligate co-operators. In our model, a behavioral game determines within-group population dynamics that then spill over into between-group dynamics. Our analysis shows that group number increases when population dynamics are stable, but additional groups lead to unstable population dynamics and an eventual collapse of group numbers. Using a more general analysis, we identify a fundamental mismatch between the stability of the behavioral dynamics and the stability of the population dynamics. When one is stable, the other is not. Our results suggest that group turnover may be inherent to the population dynamics of obligate co-operators. The instability arises from a non-chaotic deterministic process, and such dynamics should be predictable and testable.

Sex-dependent effects of chronic variable stress on discrete corticotropin-releasing factor receptor 1 cell populations.

Anxiety and depression are strikingly more prevalent in women compared with men. Dysregulation of corticotropin-releasing factor (CRF) binding to its cognate receptor (CRFR1) is thought to play a critical role in the etiology of these disorders. In the present study, we investigated whether there were sex differences in the effects of chronic variable stress (CVS) on CRFR1 cells using CRFR1-GFP reporter mice experiencing a 9-day CVS paradigm. Brains were collected from CVS and stress naïve female and male mice following exposure to the open field test. This CVS paradigm effectively increased anxiety-like behavior in female and male mice. In addition, we assessed changes in activation of CRFR1 cells (co-localization with c-Fos and phosphorylated CREB (pCREB)) in stress associated brain structures, including two sexually dimorphic CRFR1 cell groups in the anteroventral periventricular nucleus (AVPV/PeN; F>M) and paraventricular hypothalamus (PVN; M>F). CVS increased CRFR1-GFP cell number as well as the number of CRFR1/pCREB co-expressing cells in the female but not male AVPV/PeN. In the PVN, the number of CRFR1/pCREB co-expressing cells was overall greater in males regardless of treatment and CVS resulted in a male-specific reduction of CRFR1/c-Fos cells. In addition, CVS induced a female-specific reduction in CRFR1/c-Fos cells within the anteroventral bed nucleus of the stria terminalis and both sexes exhibited a reduction in CRFR1/c-Fos co-expressing cells following CVS within the ventral basolateral amygdala. Overall, these sex-specific effects of CVS on CRFR1 populations may have implications for sex differences in stress-induction of mood disorders.

Characterization and gonadal hormone regulation of a sexually dimorphic corticotropin-releasing factor receptor 1 cell group.

Corticotropin-releasing factor binds with high affinity to CRF receptor 1 (CRFR1) and is implicated in stress-related mood disorders such as anxiety and depression. Using a validated CRFR1-green fluorescent protein (GFP) reporter mouse, our laboratory recently discovered a nucleus of CRFR1 expressing cells that is prominent in the female rostral anteroventral periventricular nucleus (AVPV/PeN), but largely absent in males. This sex difference is present in the early postnatal period and remains dimorphic into adulthood. The present investigation sought to characterize the chemical composition and gonadal hormone regulation of these sexually dimorphic CRFR1 cells using immunohistochemical procedures. We report that CRFR1-GFP-ir cells within the female AVPV/PeN are largely distinct from other dimorphic cell populations (kisspeptin, tyrosine hydroxylase). However, CRFR1-GFP-ir cells within the AVPV/PeN highly co-express estrogen receptor alpha as well as glucocorticoid receptor. A single injection of testosterone propionate or estradiol benzoate on the day of birth completely eliminates the AVPV/PeN sex difference, whereas adult gonadectomy has no effect on CRFR1-GFP cell number. These results indicate that the AVPV/PeN CRFR1 is regulated by perinatal but not adult gonadal hormones. Finally, female AVPV/PeN CRFR1-GFP-ir cells are activated following an acute 30-min restraint stress, as assessed by co-localization of CRFR1-GFP cells with phosphorylated (p) CREB. CRFR1-GFP/pCREB cells were largely absent in the male AVPV/PeN. Together, these data indicate a stress and gonadal hormone responsive nucleus that is unique to females and may contribute to sex-specific stress responses.

Women's Experiences of Intimate Relationships While Living With Irritable Bowel Syndrome.

Irritable bowel syndrome is a chronic digestive disorder that commonly affects women. Research has shown that the illness experience of irritable bowel syndrome can disrupt social relationships. However, the area of intimate relationships has yet to be explored despite the deep involvement that intimate partners often have in the experience of living with chronic illness. Using a critical feminist lens, a narrative methodology was employed to explore women's experiences of intimate relationships while living with irritable bowel syndrome. Data collection methods included semistructured interviews and an arts-informed activity. The women's narrative accounts and artistic pieces reflected the emotional, physical, and interpersonal aspects of intimacy while living with irritable bowel syndrome. The findings indicated that women's experiences were deeply emotional and involved laborious and gendered emotion work. Their body concept complicated their relationship experiences. Women's emotional and social well-being was fostered by their partners' provision of acceptance, understanding, and support. The findings highlighted the need to implement and further explore the inclusion of emotional support and counselling as well as dyadic and gendered approaches to irritable bowel syndrome management.

Comparative review of the safety and efficacy of ferric carboxymaltose versus standard medical care for the treatment of iron deficiency anemia in bariatric and gastric surgery patients.

BACKGROUND: Iron deficiency anemia (IDA) is a common finding in patients after bariatric surgery. The cause is multifactorial including reduced oral iron intake and malabsorption. While many patients can be managed with oral supplements, parenteral iron may be needed to restore and maintain iron stores. METHODS: Subjects who had previous bariatric surgery and had participated in phase 3 industry-sponsored clinical trials designed to assess the safety and/or efficacy of intravenous (IV) ferric carboxymaltose (FCM) were retrospectively selected from the databases of each of these studies. Demographic data, efficacy measures [hemoglobin, ferritin, and transferrin saturation (TSAT)], and adverse events were compared between FCM and other agents utilized as comparators in the trials. RESULTS: Two hundred eighty-one subjects from the intention to treat (ITT) population were included (mean age 49 years, BMI 33 kg/m(2), including 253 females). FCM had similar or improved efficacy (p < 0.05) in terms of increasing hemoglobin, ferritin, and TSAT values when compared to other iron products used as standard of care for IDA. The incidence of adverse events in the FCM patients (n = 123) versus patients receiving any IV iron (n = 126) was 61 and 56.3 %, respectively. The adverse events were similar in both groups with the exception of a transient decrease in serum phosphate which was observed more frequently in the FCM group. CONCLUSIONS: These data in post-bariatric surgery IDA patients suggest that FCM is a safe and effective alternative to existing iron products permitting higher and thus less frequent individual doses.

Management of iron deficiency and anemia after Roux-en-Y gastric bypass surgery: an observational study.

BACKGROUND: Iron deficiency (ID) is common after Roux-en-Y gastric bypass surgery (RYGB). Optimal iron management in this population is unclear. The objective of this study was to assess our management of RYGB patients with ID and anemia. METHODS: Clinic visit records of RYGB patients with ID or anemia from January 1, 2008, to February 1, 2010 were evaluated. Demographic characteristics, postsurgery iron and anemia indices, and prescribed treatments were recorded. Three separate definitions for ID and anemia were used (standard textbook, ASBMS, and recent literature). An intravenous iron protocol was later implemented, and follow-up laboratory values were obtained. RESULTS: A total of 125 with ID or anemia (89% female, 86% Caucasian), mean (SD) age 44.7 (8.6) years, and BMI 47.3 (10.8) kg/m(2) at time of RYGB, were included. Proportion of values meeting criteria for ID or anemia at first follow-up: standard textbook, hemoglobin (Hb, 35%), transferrin saturation (Tsat, 48%), ferritin (28%); ASBMS, ferritin (43%); recent literature, ferritin (58%), serum iron (21%). At mean follow-up of 45.7 (43) months, oral iron (n = 49) or intravenous iron (n = 4) had been prescribed for 53 (42.4%) patients, and 32 (25.6%) patients received multiple blood transfusions. Nine patients received intravenous iron using the new protocol (400-1400 mg), resulting in increases in Hb (1.8 g/dL; P<.05) and ferritin (31.8 ng/mL; P< .002). CONCLUSION: Iron management was inadequate. Hematologic values often were deficient for sustained periods. Initially, few patients received intravenous iron after oral iron failure, many received no iron supplementation, and there was high use of blood transfusions. Subsequently, administration of intravenous iron was beneficial.

Use of Orlistat 60 mg in the management of weight loss before bariatric surgery.

BACKGROUND: Patients undergoing gastric bypass surgery are usually required to lose weight during the preoperative phase of their management. For some individuals, this is difficult to achieve with diet and exercise alone, and the use of weight loss medication may be considered a treatment option. OBJECTIVE: To evaluate the use of orlistat 60 mg taken up to 3 times daily as an adjunct to achieve the 10% preoperative weight loss recommended in this bariatric program prior to gastric bypass surgery. METHODS: The aim was to recruit 50 patients (25 treatment, 25 controls) who were in the preoperative phase of their bariatric program. Patients were referred by their physician. Control subjects were selected from individuals who were eligible but not interested in participating in the study during the same period. All patients received usual care. RESULTS: Nineteen patients (5 males) and 19 age- and sex-matched controls were included. The mean (SD) initial body mass index for the treatment versus control group was, respectively, 49.5 (10.5) versus 47.2 (4.9) kg/m(2) (p = 0.559). At 3 months, the percent excess weight (EW) loss was 2.4 (3.8) (n = 15) versus 5.5 (7.6) (n = 19) (p = 0.111) and the percent total body weight (TBW) loss was 1.2 (1.9) versus 2.9 (4.1) (p = 0.103). At 6 months, the percent EW loss was 3.6 (6.4) (n = 9) versus 10.2 (8.0) (n = 16) (p = 0.036) and the percent TBW loss was 2.0 (3.4) versus 5.4 (4.2) (p = 0.048). CONCLUSIONS: Some patients felt that orlistat was beneficial for weight loss; however, overall, they did not show benefit from its addition to their preoperative weight loss management.

Antidepressant drug therapy does not affect weight loss one year after gastric bypass surgery.

BACKGROUND: Preliminary data suggest that patients with actively treated depression should expect the same outcomes after surgery. The objective of this study was to compare weight loss 12 months after gastric bypass surgery in patients taking antidepressants before surgery (AD) versus those who were not (non-AD). METHODS: IRB approval was obtained. All patients gave informed consent prior to participating in the study. Medication and weight loss histories were retrospectively reviewed in adult patients who were followed at 12 months post-surgery. RESULTS: 145 of 364 patients were taking antidepressants at baseline. There was no significant difference in weight loss between the AD and non-AD groups at 12 months (p > 0.05). CONCLUSIONS: Taking antidepressant medication prior to gastric bypass surgery did not affect weight loss outcomes at 12 months.

Recommended nutritional supplements for bariatric surgery patients.

OBJECTIVE: To review nutritional supplements commonly required after bariatric surgery to provide a practical guide and reference source for generalist healthcare providers. DATA SOURCES: A PubMed literature search (1988-July 2008) was conducted, using the search term nutritional deficiency after bariatric surgery, and was limited to English-language literature on adult (aged >19 y) human subjects. Additional references from the selected literature were also included. STUDY SELECTION AND DATA EXTRACTION: Data were extracted from large clinical series and practice guidelines whenever possible. Case reports were used only when they were the sole information source. DATA SYNTHESIS: Nutritional deficiencies that occur after bariatric surgery depend significantly on the type of surgery performed. Restrictive procedures such as gastric banding are the least likely to cause nutritional deficits, since none of the intestine is bypassed. Malabsorptive procedures such as biliopancreatic diversion or mixed restrictive/malabsorptive procedures (eg, Roux-en-Y gastric bypass) can result in serious nutritional problems when patients do not take required supplements after surgery. Vitamins and minerals that are commonly deficient in this circumstance include vitamin B(12), calcium, vitamin D, thiamine, folic acid, iron, zinc, and magnesium. Rare ocular complications have been reported with hypovitaminosis A. CONCLUSIONS: Healthcare professionals, especially those who practice outside large bariatric centers, must be aware of the supplements required by patients who have had bariatric surgery. Many patients fail to follow up with the surgery centers and are managed by their primary care teams and community pharmacists, especially in the selection of multivitamin and nutritional supplements.

Women's health promotion within a community advanced pharmacy practice experience.

OBJECTIVE: To establish low-cost easily conducted health promotion interventions for advanced pharmacy practice experience (APPE) students in community pharmacy settings that would increase women's awareness about health issues using Food and Drug Administration (FDA) educational materials. METHODS: Students distributed fact sheets on medication use, heart disease, and diabetes to women over 45 years of age at 6 community pharmacy APPE sites. Interventions completed were either personal medication records (PMR) to identify medication-related problems (MRP) or heart health screenings followed by completion of an anonymous patient satisfaction survey instrument. RESULTS: Over 1500 fact sheets were distributed. Fifty-eight women (age 61 +/- 15 years) completed PMRs, which identified 57 MRPs in 42 patients. Twenty-four women indicated the screening was "useful/very useful" for increasing medication understanding. Sixty-three women completed heart health screenings. Thirty-one of the 40 who completed the survey instrument indicated the screening was "useful/very useful" for learning heart disease risk. CONCLUSIONS: Community pharmacy APPE students interventions identified MRPs and patients at risk for heart disease. These health promotion interventions enhanced women's awareness of these topics while guiding students to achieve the desired curricular outcomes.

Preoperative weight loss as a predictor of long-term success following Roux-en-Y gastric bypass.

BACKGROUND: All patients undergoing gastric bypass surgery at this institution are recommended to achieve a goal of 10% total body weight (TBW) loss prior to surgery. The objective of this study was to determine whether preoperative TBW correlated with 3- and 4-year weight loss outcome. METHODS: This study was conducted prospectively at a large teaching hospital. All adult patients with 3- and 4-year follow-up data since the start of the study in 1998 to September 2007 were included. All data are expressed as mean +/- SD. Pairwise correlation and ordinary least squares regression analysis was used to determine the strength of association between preoperative TBW loss and weight loss at 3 and 4 years. RESULTS: One hundred fifty patients (120 females), age 45.3 +/- 8.9 years, were included. Their body mass indexes (BMIs), preoperatively and after 3 years, were 52.2 +/- 9.8 and 35.4 +/- 8.2 kg/m(2), respectively. There was a significant correlation between preoperative and 3-year TBW lost (9.5 +/- 6.8% vs 31.9 +/- 11.7%, r = 0.302, p = 0.0002) and between excess body weight (EBW) lost preoperatively and after 3 years (16.1 +/- 11.3% vs 55.1 +/- 20.2%, r = 0.225, p = 0.006). Ninety five patients had follow-up data available at 4 years. Their mean preoperative BMI was 52.6 +/- 9.7 kg/m(2) and decreased to 37.5 +/- 9.0 kg/m(2). The TBW loss prior to and after surgery (10.0 +/- 6.5% vs 29.4 +/- 11.5%) was significantly correlated (r = 0.247, p = 0.015). The EBW loss preoperatively and after 4 years correlated positively (17.1 +/- 11.1% vs 50.8 +/- 19.8%, r = 0.205, p = 0.046). CONCLUSION: There is a significant correlation between weight loss attained preoperatively and sustained weight loss at 3 and 4 years.

Medications associated with weight gain.

OBJECTIVE: To review available literature regarding weight gain associated with commonly prescribed drugs and adjunctive therapy used to limit weight gain. DATA SOURCES: Information was retrieved from a MEDLINE English-literature search between 1995 and July 2005, with a major subject heading of weight gain/drug effects excluding complementary alternative medicines. Other limits applied included human subjects and individuals >19 years of age. Additionally, references from retrieved articles were reviewed to identify other literature sources. STUDY SELECTION AND DATA EXTRACTION: Changes in weight are generally reported as a primary or secondary outcome of many studies. Where possible, prospective, randomized, controlled trials were preferred; however, many studies were retrospective or open label. Meta-analyses and recent reviews, especially those providing a detailed description of the proposed mechanism involved in weight gain beyond the scope of this article, were included. Limited information was available from case reports. Studies were categorized by therapeutic area including psychiatry, neurology, diabetes, and other miscellaneous drug therapy. Medications used to intentionally stimulate appetite for weight gain, such as megesterol acetate, were not included. DATA SYNTHESIS: Weight gain with medication is usually associated with individual agents within a class. The tendency to cause weight gain is often related to differential specificity and sensitivity of binding to receptors involved with appetite regulation. CONCLUSIONS: Clinically significant weight gain is associated with some commonly prescribed medicines. There is wide interindividual variation in response and variation of the degree of weight gain within drug classes. Where possible, alternative therapy should be selected, especially for individuals predisposed to overweight and obesity.

The lifestyle challenge program: a multidisciplinary approach to weight management.

BACKGROUND: The increasing prevalence of overweight and obesity in the US has received widespread attention and is highlighted in recent government-issued health priorities. While there are many weight loss programs in different settings, few include pharmacist involvement in spite of pharmacists' recognized easy accessibility to the public. OBJECTIVE: To provide insight into a successful, collaborative, multidisciplinary approach to weight management and to encourage pharmacists and other healthcare professionals to adopt a similar approach to patient management. METHODS: Adult patients >18 years of age were recruited from an outpatient university-based setting to participate in a weight management program. The principles of the program included diet, exercise, and behavior modification. The program was conducted through weekly one-hour group sessions held over a 20-week period. Faculty involved in the program included an attending physician specializing in nutrition, a pharmacist, and a behavioral psychologist. All data are expressed as mean +/- SD unless otherwise specified. RESULTS: Ninety participants (74 female, mean age 48 +/- 10 y) entered the program between April 2001 and April 2004. Participants had multiple obesity-related comorbid diseases. The weight of completers (n = 59) decreased from 100.9 +/- 20 kg at baseline to 97.3 +/- 19.5 kg at 10 weeks and 95.9 +/- 20 kg at 20 weeks. Thirty-nine patients completed both baseline and final assessments, which showed improvement in health-related quality of life, binge-eating behavior, and depressive symptoms (p < 0.05). CONCLUSIONS: This program is a successful multidisciplinary model for the management of overweight and obese patients in an outpatient-based hospital setting.

Medication associated with weight gain may influence outcome in a weight management program.

BACKGROUND: Weight gain is a commonly overlooked adverse effect of some medications that potentially confounds weight loss efforts in individuals who are overweight and obese. OBJECTIVE: To determine the frequency of use of drugs associated with weight gain by participants and the effect on outcome in a weight management program. METHODS: Adult patients > 18 years of age were recruited from an outpatient, university-based setting to participate in a 20-week structured weight management program. RESULTS: Ninety patients (74 women) were recruited (mean [+/- SD] age 48 +/- 10 y, mean body mass index 37 +/- 6 kg/m2). Patients had multiple diseases including type 2 diabetes mellitus (n = 23), hypertension (n = 48), depression (n = 18), and dyslipidemia (n = 9). The median number of drugs per patient was 4.0 (range 0-15). The median number of drugs associated with weight gain was zero (range 0-3). Forty-three (48%) patients were taking at least one of these agents, including beta-blockers (n = 18), selective serotonin-reuptake inhibitors (n = 18), sulfonylureas (n = 7), insulin (n = 9), and thiazolidinediones (n = 6). Seven patients completed < or = 6 weeks of the program and were excluded from further analysis, and 83 patients completed 10 weeks. Of these 83 patients, 39 had lost < or = 2% of their initial weight; 23 (59%) of those 39 were taking drugs associated with weight gain. Fifty-nine patients completed the full 20 weeks. The mean overall weight loss of completers was 4.8 +/- 5.0% (range-5.9 [gain] to 17.1% [loss]) at 20 weeks. CONCLUSIONS: Patients taking WGDs weighed more at baseline and were less likely to lose weight in this program. Attention should be given when prescribing such medications to obese patients, as this may negatively influence their weight management.

Medication use patterns after gastric bypass surgery for weight management.

BACKGROUND: Bariatric surgery, commonly gastric bypass, is an effective intervention in achieving sustained weight loss in patients with a body mass index (BMI) >40 kg/m(2). Currently, there are few data in the literature describing medication use after bariatric surgery. OBJECTIVE: To document the change in medication use patterns over a 2-year period in patients who had gastric bypass surgery. METHODS: Institutional review board approval was obtained for this ongoing, prospective longitudinal study. Adults (>18 y) scheduled for gastric bypass surgery were recruited. Clinical and demographic data, including age, gender, weight, height, BMI, number of obesity-related comorbidities, and number of medications and nutritional supplements, were obtained by medical chart review. RESULTS: One hundred fourteen patients (87 females) were recruited. The mean +/- SD age was 45 +/- 9 years. Patients had multiple obesity-related comorbid diseases for which they were receiving medication. Drug therapy for diabetes and hypertension was significantly reduced (p < 0.05). All patients were required to take additional nutritional supplements and medications associated with surgery postoperatively. CONCLUSIONS: Bariatric surgery has a positive benefit in terms of reduction intake of medication associated with obesity-related comorbid disease. However, there is limited reduction in the overall number of drugs and supplements being consumed by the patient, especially during the first year postoperatively.