Perioperative outcomes and long-term quality of life after total pancreatectomy.

BACKGROUND: Total pancreatectomy is required to treat diseases involving the entire pancreas, and is characterized by high morbidity rates and impaired long-term quality of life (QoL). To date, risk factors associated with perioperative and long-term outcomes have not been determined fully. METHODS: Data from patients undergoing total pancreatectomy between 2000 and 2014 at two high-volume centres were analysed retrospectively to assess risk factors for major surgical complications. Short Form (SF) 36, European Organisation for Research and Treatment of Cancer QLQ-PAN26 and Audit of Diabetes Dependent questionnaires, as well as an original survey were used to investigate factors influencing QoL. RESULTS: A total of 329 consecutive patients underwent total pancreatectomy in the two centres. Overall, total pancreatectomy was associated with a morbidity rate of 59·3 per cent and a 30-day mortality rate of 2·1 per cent. Age over 65 years and long duration of surgery (more than 420 min) were independently associated with major complications (at least Clavien-Dindo grade III). QoL analysis was available for 94 patients (28·6 per cent) with a median follow-up of 63 (i.q.r. 20-109) months; the most common indication for total pancreatectomy in these patients was intraductal papillary mucinous neoplasms (46 per cent). Both physical (PCS) and mental (MCS) component summary scores of SF-36® were lower after total pancreatectomy compared with scores for a normative population (P = 0·020 and P < 0·001 respectively). Linear regression analysis showed that young age, abdominal pain and worse perception of body image were negatively associated with the PCS, whereas diabetes, sexual satisfaction and perception of body image affected MCS. CONCLUSION: Total pancreatectomy can be performed with acceptable morbidity and mortality rates. Older patients had a higher risk of postoperative complications but reported better QoL than younger patients.

ANTECEDENTES: La pancreatectomía total es una cirugía necesaria para tratar enfermedades que afectan a la totalidad el páncreas y se caracteriza por una alta morbilidad y una disminución de la calidad de vida (QoL) a largo plazo. Hasta la fecha, los factores de riesgo asociados a los resultados perioperatorios y a largo plazo no han sido completamente determinados. MÉTODOS: Los datos de los pacientes que se sometieron a una pancreatectomía total desde el año 2000 al 2015 en dos centros de alto volumen se analizaron retrospectivamente para evaluar los factores de riesgo de las complicaciones quirúrgicas mayores. Se utilizaron el SF-36, el EORTC-PAN-26, los cuestionarios ADD-QoL y una encuesta original para investigar los factores que afectan la QoL. RESULTADOS: Un total de 329 pacientes consecutivos se sometieron a una pancreatectomía total en los dos centros. En general, la pancreatectomía total se asoció a un 59,3% de morbilidad y un 2,1% de mortalidad a los 30 días. La edad > 65 años y el tiempo operatorio prolongado (> 420 minutos) se asociaron de forma independiente a las complicaciones Clavien-Dindo ≥ III. El análisis de QoL estuvo disponible en 94 (28,6%) de los pacientes con una mediana de seguimiento de 63 meses (rango intercuartílico 20-109) y la indicación más común fue una neoplasia papilar mucinosa intraductal (IPMN) (45,7%). Las puntuaciones del SF-36 fueron más bajas en ambos componentes sumatorios físico (PCS) y mental (MCS) (P = 0,002; P < 0,001) en comparación con una población normal. El modelo de regresión lineal mostró que la edad joven, el dolor abdominal y la peor percepción de la imagen corporal se asociaron negativamente con el PCS; mientras que la diabetes, la satisfacción sexual y la percepción de la imagen corporal afectaron al MCS. CONCLUSIÓN: Se puede realizar una pancreatectomía total con morbilidad y mortalidad aceptables. Los pacientes de mayor edad tienen un riesgo más elevado de complicaciones postoperatorias, pero presentaron mejor QoL que los pacientes más jóvenes.

Genetic And Morphological Evaluation (GAME) score for patients with colorectal liver metastases.

BACKGROUND: This study sought to develop a clinical risk score for resectable colorectal liver metastasis (CRLM) by combining clinicopathological and clinically available biological indicators, including KRAS. METHODS: A cohort of patients who underwent resection for CRLM at the Johns Hopkins Hospital (JHH) was analysed to identify independent predictors of overall survival (OS) that can be assessed before operation; these factors were combined into the Genetic And Morphological Evaluation (GAME) score. The score was compared with the current standard (Fong score) and validated in an external cohort of patients from the Memorial Sloan Kettering Cancer Center (MSKCC). RESULTS: Six preoperative predictors of worse OS were identified on multivariable Cox regression analysis in the JHH cohort (502 patients). The GAME score was calculated by allocating points to each patient according to the presence of these predictive factors: KRAS-mutated tumours (1 point); carcinoembryonic antigen level 20 ng/ml or more (1 point), primary tumour lymph node metastasis (1 point); Tumour Burden Score between 3 and 8 (1 point) or 9 and over (2 points); and extrahepatic disease (2 points). The high-risk group in the JHH cohort (GAME score at least 4 points) had a 5-year OS rate of 11 per cent, compared with 73·4 per cent for those in the low-risk group (score 0-1 point). Importantly, in cohorts from both the JHH and MSKCC (747 patients), the discriminatory capacity of the GAME score was superior to that of the Fong score, as demonstrated by the C-index and the Akaike information criterion. CONCLUSION: The GAME score is a preoperative prognostic tool that can be used to inform treatment selection.

Chronic combined hyperandrogenemia and western-style diet in young female rhesus macaques causes greater metabolic impairments compared to either treatment alone.

STUDY QUESTION: Does developmental exposure to the combination of hyperandrogenemia and western-style diet (WSD) worsen adult metabolic function compared to either treatment alone? SUMMARY ANSWER: Young female rhesus macaques treated for 3 years, beginning at menarche, with combined testosterone (T) and WSD have increased weight gain and insulin resistance compared to controls and animals treated with either T or WSD alone. WHAT IS KNOWN ALREADY: Hyperandrogenemia is a well-established component of polycystic ovary syndrome (PCOS) and can be observed in peripubertal girls, indicating a potential pubertal onset of the disease. Obesity is often associated with hyperandrogenemia in peripubertal girls, and overweight girls appear to be at higher risk for the development of PCOS later in life. STUDY DESIGN, SIZE, DURATION: Juvenile (2.5- year old) female rhesus macaques were divided into four groups (n = 10/group): control animals receiving cholesterol implants and a control diet with 15% of calories derived from fat (C), animals receiving T implants (mean serum levels: 1.35 ± 0.01 ng/ml) and a control diet (T), animals receiving a cholesterol implant and a WSD with 36% of calories derived from fat (WSD) and animals receiving a T implant and a WSD (T + WSD). Animals were maintained on the treatments for 36 months and were 5.5 years old at study completion. PARTICIPANTS/MATERIALS, SETTING, METHODS: Metabolic testing consisted of body measurements including weight, dual-energy X-ray absorptiometry scans, activity monitoring, and glucose tolerance testing at zero months and at least once every 12 months for the remainder of the study. Indirect calorimetry and serum hormone assays were performed following 36 months of treatment. MAIN RESULTS AND THE ROLE OF CHANCE: Body weight and fat mass gain were significantly increased in T + WSD at 24 and 36 months of treatment compared to the other three groups. Log transformed fasting insulin and Homeostatic Model Assessment of Insulin Resistance (HOMA-IR) were significantly increased in T + WSD animals at 3 years of treatment compared to all other groups. T-treatment caused a greater rate of decline in activity after 18 months, while food intake and metabolic rate were largely unaffected by treatments. LIMITATIONS REASONS FOR CAUTION: Variability was present in the metabolic parameters measured; however, this is similar to the heterogeneity observed in human populations. WIDER IMPLICATIONS OF THE FINDINGS: Chronic hyperandrogenemia beginning at puberty may exacerbate metabolic dysfunction in women consuming a WSD and account for the increased rates of obesity and insulin resistance observed in PCOS patients. Counseling of female patient populations with elevated androgens about the potential benefit of consuming a lower fat diet could improve long-term metabolic health outcomes. STUDY FUNDING/COMPETING INTEREST(S): Eunice Kennedy Shriver National Institute of Child Health & Human Development P50HD071836 and Oregon National Primate Center Grant P51 OD011092. The authors have no competing conflict of interests to disclose.

Perpetuating effects of androgen deficiency on insulin resistance.

BACKGROUND/OBJECTIVES: Androgen deprivation therapy (ADT) is commonly used for treatment of prostate cancer but is associated with side effects, such as sarcopenia and insulin resistance. The role of lifestyle factors such as diet and exercise on insulin sensitivity and body composition in testosterone-deficient males is poorly understood. The aim of the present study was to examine the relationships between androgen status, diet and insulin sensitivity. SUBJECTS/METHODS: Middle-aged (11-12 years old) intact and orchidectomized male rhesus macaques were maintained for 2 months on a standard chow diet and then exposed for 6 months to a Western-style, high-fat/calorie-dense diet (WSD) followed by 4 months of caloric restriction (CR). Body composition, insulin sensitivity, physical activity, serum cytokine levels and adipose biopsies were evaluated before and after each dietary intervention. RESULTS: Both intact and orchidectomized animals gained similar proportions of body fat, developed visceral and subcutaneous adipocyte hypertrophy and became insulin resistant in response to the WSD. CR reduced body fat in both groups but reversed insulin resistance only in intact animals. Orchidectomized animals displayed progressive sarcopenia, which persisted after the switch to CR. Androgen deficiency was associated with increased levels of interleukin-6 and macrophage-derived chemokine (C-C motif chemokine ligand 22), both of which were elevated during CR. Physical activity levels showed a negative correlation with body fat and insulin sensitivity. CONCLUSIONS: Androgen deficiency exacerbated the negative metabolic side effects of the WSD such that CR alone was not sufficient to improve altered insulin sensitivity, suggesting that ADT patients will require additional interventions to reverse insulin resistance and sarcopenia.

Analysis of new workers' compensation claims in the Department of Defense civilian workforce, 2000-2012.

OBJECTIVE: This study of Department of Defense (DoD) civilian employees Workers' Compensation (WC) claims for chargeback year 2000 through 2012 aimed to analyze the frequency, rates, and costs of WC claims representing 5% of the DoD annual personnel budget. METHODS: A multiyear cross-sectional study of WC claims data identified the top five most frequent causes, natures, and anatomical sites; changes in frequency, worker age, costs, and time were evaluated for trends. RESULTS: The annual frequency and rate of new DoD WC claims decreased over time, whereas costs per new claim have increased. New claim frequencies, rates, and costs aggregated in older age groups. CONCLUSIONS: The increasing trend in costs of each claim and the overall program costs presents a need for case management. Analysis of WC claims data is necessary to help target injury prevention efforts and reduce program costs.

Federal workers' compensation program basics.

OBJECTIVE: Primary health care providers may not be familiar with the Federal Employees' Compensation Act (FECA) and Department of Defense regulations that govern injured workers' rights, benefits, and procedures to follow when an injured employee is seen in the military medical treatment facility. METHODS: The FECA program was examined and each section reviewed to facilitate provider involvement from time of injury to final disposition of a claim and employee return to work. The best practices in case management are highlighted as well. RESULTS: Several areas of the FECA program require coordination between members of the installation Federal Worker's Compensation team. Areas requiring extensive communication by all team members were emphasized. CONCLUSIONS: Successful installation FECA programs engage all members of the FECA team in a collaborative fashion to share information, prevent injuries, and keep costs low.

Sensing-enabled hippocampal deep brain stimulation in idiopathic nonhuman primate epilepsy.

Epilepsy is a debilitating condition affecting 1% of the population worldwide. Medications fail to control seizures in at least 30% of patients, and deep brain stimulation (DBS) is a promising alternative treatment. A modified clinical DBS hardware platform was recently described (PC+S) allowing long-term recording of electrical brain activity such that effects of DBS on neural networks can be examined. This study reports the first use of this device to characterize idiopathic epilepsy and assess the effects of stimulation in a nonhuman primate (NHP). Clinical DBS electrodes were implanted in the hippocampus of an epileptic NHP bilaterally, and baseline local field potential (LFP) recordings were collected for seizure characterization with the PC+S. Real-time automatic detection of ictal events was demonstrated and validated by concurrent visual observation of seizure behavior. Seizures consisted of large-amplitude 8- to 25-Hz oscillations originating from the right hemisphere and quickly generalizing, with an average occurrence of 0.71 ± 0.15 seizures/day. Various stimulation parameters resulted in suppression of LFP activity or in seizure induction during stimulation under ketamine anesthesia. Chronic stimulation in the awake animal was studied to evaluate how seizure activity was affected by stimulation configurations that suppressed broadband LFPs in acute experiments. This is the first electrophysiological characterization of epilepsy using a next-generation clinical DBS system that offers the ability to record and analyze neural signals from a chronically implanted stimulating electrode. These results will direct further development of this technology and ultimately provide insight into therapeutic mechanisms of DBS for epilepsy.

Quantitative Genetics of Response to Novelty and Other Stimuli by Infant Rhesus Macaques (Macaca mulatta) Across Three Behavioral Assessments.

Primate behavior is influenced by both heritable factors and environmental experience during development. Previous studies of rhesus macaques (Macaca mulatta) examined the effects of genetic variation on expressed behavior and related neurobiological traits (heritability and/or genetic association) using a variety of study designs. Most of these prior studies examined genetic effects on the behavior of adults or adolescent rhesus macaques, not in young macaques early in development. To assess environmental and additive genetic variation in behavioral reactivity and response to novelty among infants, we investigated a range of behavioral traits in a large number (N = 428) of pedigreed infants born and housed in large outdoor corrals at the Oregon National Primate Research Center (ONPRC). We recorded the behavior of each subject during a series of brief tests, involving exposure of each infant to a novel environment, to a social threat without the mother present, and to a novel environment with its mother present but sedated. We found significant heritability (h2 ) for willingness to move away from the mother and explore a novel environment (h2 = 0.25 ± 0.13; P = 0.003). The infants also exhibited a range of heritable behavioral reactions to separation stress or to threat when the mother was not present (h2 = 0.23 ± 0.13-0.24 ± 0.15, P < 0.01). We observed no evidence of maternal environmental effects on these traits. Our results extend knowledge of genetic influences on temperament and reactivity in nonhuman primates by demonstrating that several measures of behavioral reactivity among infant rhesus macaques are heritable.

Effects of hyperandrogenemia and increased adiposity on reproductive and metabolic parameters in young adult female monkeys.

Many patients with hyperandrogenemia are overweight or obese, which exacerbates morbidities associated with polycystic ovary syndrome (PCOS). To examine the ability of testosterone (T) to generate PCOS-like symptoms, monkeys received T or cholesterol (control) implants (n = 6/group) beginning prepubertally. As previously reported, T-treated animals had increased neuroendocrine drive to the reproductive axis [increased luteinizing hormone (LH) pulse frequency] at 5 yr, without remarkable changes in ovarian or metabolic features. To examine the combined effects of T and obesity, at 5.5 yr (human equivalent age: 17 yr), monkeys were placed on a high-calorie, high-fat diet typical of Western cultures [Western style diet (WSD)], which increased body fat from <2% (pre-WSD) to 15-19% (14 mo WSD). By 6 mo on WSD, LH pulse frequency in the controls increased to that of T-treated animals, whereas LH pulse amplitude decreased in both groups and remained low. The numbers of antral follicles present during the early follicular phase increased in both groups on the WSD, but maximal follicular size decreased by 50%. During the late follicular phase, T-treated females had greater numbers of small antral follicles than controls. T-treated monkeys also had lower progesterone during the luteal phase of the menstrual cycle. Although fasting insulin did not vary between groups, T-treated animals had decreased insulin sensitivity after 1 yr on WSD. Thus, while WSD consumption alone led to some features characteristic of PCOS, T + WSD caused a more severe phenotype with regard to insulin insensitivity, increased numbers of antral follicles at midcycle, and decreased circulating luteal phase progesterone levels.

Hypothalamic KISS1 expression, gonadotrophin-releasing hormone and neurotransmitter innervation vary with stress and sensitivity in macaques.

The present study examined the effect of short-term psychosocial and metabolic stress in a monkey model of stress-induced amenorrhaea on the hypothalamic-pituitary-gonadal axis. KISS1 expression was determined by in situ hybridisation in the infundibular arcuate nucleus. Downstream of KISS1, gonadotrophin-releasing hormone (GnRH) axons in lateral areas rostral to the infundibular recess, serum luteinising hormone (LH) and serum oestradiol were measured by immunohistochemistry and radioimmunoassay. Upstream of KISS1, norepinephrine axons in the rostral arcuate nucleus and serotonin axons in the anterior hypothalamus and periaqueductal grey were measured by immunohistochemistry. Female cynomolgus macaques (Macaca fascicularis) characterised as highly stress resilient (HSR) or stress sensitive (SS) were examined. After characterisation of stress sensitivity, monkeys were either not stressed, or mildly stressed for 5 days before euthanasia in the early follicular phase. Stress consisted of 5 days of 20% food reduction in a novel room with unfamiliar conspecifics. There was a significant increase in KISS1 expression in HSR and SS animals in the presence versus absence of stress (P = 0.005). GnRH axon density increased with stress in HSR and SS animals (P = 0.015), whereas LH showed a gradual but nonsignificant increase with stress. Oestradiol trended higher in HSR animals and there was no effect of stress (P = 0.83). Norepinephrine axon density (marked with dopamine ß-hydroxylase) increased with stress in both HSR and SS groups (P ≤ 0.002), whereas serotonin axon density was higher in HSR compared to SS animals and there was no effect of stress (P = 0.03). The ratio of dopamine ß-hydroxylase/oestradiol correlated with KISS1 (P = 0.052) and GnRH correlated with serum LH (P = 0.039). In conclusion, oestradiol inhibited KISS1 in the absence of stress, although stress increased norepinephrine, which may over-ride oestradiol inhibition of KISS1 expression. We speculate that neural pathways transduce stress to KISS1 neurones, which changes their sensitivity to oestradiol.

Resection of isolated renal cell carcinoma metastases of the pancreas: outcomes from the Johns Hopkins Hospital.

PURPOSE: This study aims to assess outcomes and characteristics associated with resection of metastatic renal cell carcinoma (mRCC) to the pancreas. MATERIALS AND METHODS: From April 1989 to July 2012, a total of 42 patients underwent resection of pancreatic mRCC at our institution. We retrospectively reviewed records from a prospectively managed database and analyzed patient demographics, comorbidities, perioperative outcomes, and overall survival. Cox proportional hazards models were used to evaluate the association between patient-specific factors and overall survival. RESULTS: The mean time from resection of the primary tumor to reoperation for pancreatic mRCC was 11.2 years (range, 0-28.0 years). In total, 17 patients underwent pancreaticoduodenectomy, 16 underwent distal pancreatectomy, and 9 underwent total pancreatectomy. Perioperative complications occurred in 18 (42.9%) patients; there were two (4.8%) perioperative mortalities. After pancreatic resection, the median follow-up was 7.0 years (0.1-23.2 years), and median survival was 5.5 years (range, 0.4-21.9). The overall 5-year survival was 51.8%. On univariate analysis, vascular invasion (hazard ratio, 5.15; p = 0.005) was significantly associated with increased risk of death. CONCLUSIONS: Pancreatic resection of mRCC can be safely achieved in the majority of cases and is associated with long-term survival. Specific pathological factors may predict which patients will benefit most from resection.

Elevated androgens during puberty in female rhesus monkeys lead to increased neuronal drive to the reproductive axis: a possible component of polycystic ovary syndrome.

BACKGROUND: Hyperandrogenemia is associated with several clinical disorders in which both reproductive dysfunction and metabolic changes may coexist [i.e. polycystic ovary syndrome (PCOS), obesity and congenital adrenal hyperplasia]. Moreover, there is growing evidence that the elevated levels of circulating androgens in obese girls may lead to an increased neuroendocrine drive to the reproductive axis, similar to that associated with PCOS. METHODS: To test whether androgen exposure in the childhood and adolescent period could lead to pubertal alterations in LH secretory patterns, female rhesus monkeys received subcutaneous testosterone implants prepubertally beginning at 1 year of age, maintaining a 3.7-fold increase (P = 0.001) in circulating testosterone levels over cholesterol-implant controls (n = 6/group) into the post-pubertal period. In early adulthood, pulsatile secretion of LH was measured over 12 h during the early follicular phase of a menstrual cycle, and responsiveness of the pituitary to gonadotrophin-releasing hormone was determined. In addition, ultrasounds were performed to assess ovarian morphology and glucose tolerance testing was performed to assess insulin sensitivity. RESULTS: The timing of menarche was similar between groups. Testosterone-treated animals had a significantly greater LH pulse frequency during the early follicular phase compared with controls (P = 0.039) when measured at 5 years of age. There was a larger LH response to GnRH when testosterone-treated animals were 4 years of age (P = 0.042), but not when the animals were 5 years old (P = 0.57). No differences were seen in insulin sensitivity or ovarian morphology, and the groups showed similar rates of ovulation in early adulthood. CONCLUSIONS: Exposure to increased levels of androgens over the course of pubertal development appears to trigger physiological changes in the neural drive to the reproductive axis that resemble those of obese hyperandrogenemic girls in early adulthood and are characteristic of PCOS.

Treatment with a CRH-R1 antagonist prevents stress-induced suppression of the central neural drive to the reproductive axis in female macaques.

In response to everyday life stress, some individuals readily develop reproductive dysfunction (i.e., they are stress sensitive), whereas others are more stress resilient. When exposed to mild combined psychosocial plus metabolic stress (change in social environment plus reduced diet), female cynomolgus monkeys can be categorized as stress sensitive (SS; they rapidly become anovulatory in response to stress), medium stress resilient (MSR; they slowly become anovulatory in response to prolonged stress), or highly stress resilient (HSR; they maintain normal menstrual cycles in response to stress). Previously, we reported that monkeys that develop abnormal menstrual cycles following exposure to mild combined stress (MSR + SS) have increased plasma cortisol levels the day they move to a novel room and start a reduced diet compared with HSR monkeys. In this study, we examined whether there is a similar acute effect of mild combined stress on the reproductive axis specifically in the combined group of MSR + SS animals by measuring LH pulse frequency and whether treatment with a CRH-R1 antagonist can prevent a stress-induced suppression of LH pulse frequency presumably by inhibiting activity of the HPA axis. Animals that developed abnormal menstrual cycles in response to stress (MSR + SS monkeys) suppressed LH pulse frequency in response to stress exposure. Pretreatment with 10 mg/kg iv antalarmin prevented the stress-induced suppression of LH secretion in these animals without the stress-induced increase in cortisol secretion being blocked. We conclude that CRH, acting via nonneuroendocrine mechanisms to regulate neurotransmitter systems other than the HPA axis, plays a role in causing stress-induced reproductive impairment in stress-sensitive individuals.

Sensitivity to stress-induced reproductive dysfunction is associated with a selective but not a generalized increase in activity of the adrenal axis.

Stress-induced reproductive dysfunction is a relatively common cause of infertility in women. In response to everyday life stress, some individuals readily develop reproductive dysfunction (i.e., they are stress sensitive), whereas others are more stress resilient. Female cynomolgus monkeys, when exposed to mild combined psychosocial and metabolic stress (change in social environment + 20% reduced calorie diet), can be categorized as stress sensitive (SS; they rapidly become anovulatory in response to stress), medium stress resilient (MSR; they slowly become anovulatory in response to prolonged stress), or highly stress resilient (HSR; they maintain normal menstrual cycles in response to stress). In this study, we examined whether increased sensitivity to stress-induced reproductive dysfunction is associated with elevated adrenal axis activity by measuring 1) the diurnal release of ACTH and cortisol, 2) ACTH and cortisol in response to an acute psychological stress, 3) the percent suppression of cortisol in response to dexamethasone negative feedback, 4) the diurnal release of ACTH and cortisol following exposure to mild psychosocial and metabolic stress, 5) the concentration of cortisol in hair, and 6) adrenal weight. SS monkeys (n = 5) did not differ from MSR (n = 5) or HSR (n = 7) monkeys in any measurement of baseline HPA axis activity or the integrated measurements of chronic HPA axis activity. However, MSR + SS monkeys (n = 10) did secrete more cortisol than HSR monkeys during the daytime hours (1000-1800) following exposure to a novel social environment and reduced diet. We conclude that increased activity of the HPA axis is unlikely to be the primary mechanism causing increased sensitivity to stress-induced reproductive dysfunction.

Effects of aerobic exercise training on cognitive function and cortical vascularity in monkeys.

This study examined whether regular exercise training, at a level that would be recommended for middle-aged people interested in improving fitness could lead to improved cognitive performance and increased blood flow to the brain in another primate species. Adult female cynomolgus monkeys were trained to run on treadmills for 1 h a day, 5 days a week, for a 5 month period (n=16; 1.9+/-0.4 miles/day). A sedentary control group sat daily on immobile treadmills (n=8). Half of the runners had an additional sedentary period for 3 months at the end of the exercise period (n=8). In all groups, half of the monkeys were middle-aged (10-12 years old) and half were more mature (15-17 years old). Starting the fifth week of exercise training, monkeys underwent cognitive testing using the Wisconsin General Testing Apparatus (WGTA). Regardless of age, the exercising group learned to use the WGTA significantly faster (4.6+/-3.4 days) compared to controls (8.3+/-4.8 days; P=0.05). At the end of 5 months of running monkeys showed increased fitness, and the vascular volume fraction in the motor cortex in mature adult running monkeys was increased significantly compared to controls (P=0.029). However, increased vascular volume did not remain apparent after a 3-month sedentary period. These findings indicate that the level of exercise associated with improved fitness in middle-aged humans is sufficient to increase both the rate of learning and blood flow to the cerebral cortex, at least during the period of regular exercise.

Stress sensitive female macaques have decreased fifth Ewing variant (Fev) and serotonin-related gene expression that is not reversed by citalopram.

Female cynomolgus monkeys exhibit different degrees of reproductive dysfunction with moderate metabolic and psychosocial stress. When stressed with a paradigm of relocation and diet for 60 days or two menstrual cycles, highly stress resilient monkeys (HSR) continued to ovulate during the stress cycles whereas stress sensitive monkeys (SS) did not. After cessation of stress, monkeys characterized as HSR or SS were administered placebo (PL) or S-citalopram (CIT) for 15 weeks at doses that normalized ovarian steroid secretion in the SS animals and that maintained blood CIT levels in a therapeutic range. After euthanasia, the brain was perfused with 4% paraformaldehyde. The pontine midbrain was blocked and sectioned at 25 microm. The expression of four genes pivotal to serotonin neural function was assessed in the four groups of monkeys (n=4/group). Fev (fifth Ewing variant) ETS transcription factor, tryptophan hydroxylase 2 (TPH2), the serotonin reuptake transporter (SERT), and the 5HT1A autoreceptor were determined at 7-8 levels of the dorsal raphe nucleus with in situ hybridization (ISH) using radiolabeled- and digoxygenin-incorporated riboprobes. Positive pixel area and cell number were measured with Slidebook 4.2 in the digoxigenin assay for Fev. Optical density (OD) and positive pixel area were measured with NIH Image software in the radiolabeled assays for TPH2, SERT and 5HT1A. All data were analyzed with two-way ANOVA. SS monkeys had significantly fewer Fev-positive cells and lower Fev-positive pixel area in the dorsal raphe than HSR monkeys. SS monkeys also had significantly lower levels of TPH2, SERT and 5HT1A mRNAs in the dorsal raphe nucleus than HSR monkeys. However, CIT did not alter the expression of either Fev, TPH2, SERT or 5HT1A mRNAs. These data suggest that SS monkeys have fewer serotonin (5-HT) neurons than HSR monkeys, and that they have deficient Fev expression, which in turn, leads to deficient TPH2, SERT and 5HT1A expression. In addition, the therapeutic effect of CIT is probably achieved through mechanisms other than alteration of 5-HT-related gene expression.

Hypothalamic gonadotrophin-releasing hormone expression in female monkeys with different sensitivity to stress.

Psychosocial stress, combined with mild dieting and moderate exercise, are observed in women seeking treatment for hypothalamic amenorrhea. Using female cynomolgus macaques, we previously reported that the same combination of mild stresses suppressed reproductive hormone secretion and menstrual cycles in some individuals (stress-sensitive, SS), but not in others (highly stress-resilient, HSR). Compared to HSR monkeys, SS monkeys exhibited lower oestradiol and progesterone levels at the midcycle peak and decreased gene expression in the central serotonergic system during nonstressed cycles. Because steroids and serotonin impinge upon the hypothalamic-pituitary-gonadal (HPG) axis, we hypothesised that the differences between SS and HSR monkeys in the sensitivity of the HPG axis to stress may ultimately manifest in differences in the gonadotrophin-releasing hormone (GnRH) system. GnRH in situ hybridisation and immunohistochemistry were performed with hypothalamic sections from SS and HSR animals, euthanised in the early follicular phase of a nonstressed menstrual cycle. Compared to HSR monkeys, SS monkeys exhibited a significantly higher number and density of GnRH cell bodies, as well as a higher number of soma with extremely robust expression of GnRH mRNA, but SS monkeys exhibited a lower density of immunostained GnRH fibres in the median eminence. We suggest that neuronal mechanisms involved in the control of GnRH synthesis, transport and release differ in SS compared to HSR animals.

Serotonin-related gene expression in female monkeys with individual sensitivity to stress.

Female cynomolgus monkeys exhibit different degrees of reproductive dysfunction with moderate metabolic and psychosocial stress. In this study, the expression of four genes pivotal to serotonin neural function was assessed in monkeys previously categorized as highly stress resistant (n=3; normal menstrual cyclicity through two stress cycles), medium stress resistant (n=5; ovulatory in the first stress cycle but anovulatory in the second stress cycle), or low stress resistant (i.e. stress-sensitive; n=4; anovulatory as soon as stress is initiated). In situ hybridization and quantitative image analysis was used to measure mRNAs coding for SERT (serotonin transporter), 5HT1A autoreceptor, MAO-A and MAO-B (monoamine oxidases) at six levels of the dorsal raphe nucleus (DRN). Optical density (OD) and positive pixel area were measured with NIH Image software. In addition, serotonin neurons were immunostained and counted at three levels of the DRN. Finally, each animal was genotyped for the serotonin transporter long polymorphic region (5HTTLPR). Stress sensitive animals had lower expression of SERT mRNA in the caudal region of the DRN (P<0.04). SERT mRNA OD in the caudal DRN was positively correlated with serum progesterone during a pre-stress control cycle (P<0.0007). 5HT1A mRNA OD signal tended to decline in the stress-sensitive group, but statistical difference between averages was lacking in analysis of variance. However, 5HT1A mRNA signal was positively correlated with control cycle progesterone (P<0.009). There was significantly less MAO-A mRNA signal in the stress-sensitive group (P<0.007) and MAO-A OD was positively correlated with progesterone from a pre-stress control cycle (P<0.007). MAO-B mRNA exhibited a similar downward trend in the stress-sensitive group. MAO-B OD also correlated with control cycle progesterone (P<0.003). There were significantly fewer serotonin neurons in the stress-sensitive group. All animals contained only the long form of the 5HTTLPR. Thus, all serotonin-related mRNAs examined in the dorsal raphe to date were lower (SERT, MAO-A) or exhibited a lower trend (5HT1A, MAO-B) in the stress sensitive animals, which probably reflects the lower number of serotonin neurons present.

STK11/LKB1 Peutz-Jeghers gene inactivation in intraductal papillary-mucinous neoplasms of the pancreas.

Despite the growing awareness of intraductal papillary-mucinous neoplasms (IPMNs) of the pancreas among clinicians, the molecular features of IPMNs have not been well characterized. Previous reports suggest that inactivation of the STK11/LKB1, a tumor-suppressor gene responsible for Peutz-Jeghers syndrome (PJS), plays a role in the pathogenesis of gastrointestinal hamartomas as well as several cancers, including pancreatic adenocarcinoma. Using polymerase chain reaction amplification of five microsatellite markers from the 19p13.3 region harboring the STK11/LKB1 gene, we analyzed DNA from 22 IPMNs for loss of heterozygosity (LOH). LOH at 19p13.3 was identified in 2 of 2 (100%) IPMNs from patients with PJS and 5 of 20 (25%) from patients lacking features of PJS (7 of 22, 32% overall). Sequencing analysis of the STK11/LKB1 gene in these IPMNs with LOH revealed a germline mutation in one IPMN that arose in a patient with PJS and a somatic mutation in 1 of the 20 sporadic IPMNs. None of the 22 IPMNs showed hypermethylation of the STK11/LKB1 gene. These results suggest that the STK11/LKB1 gene is involved in the pathogenesis of some IPMNs.