Correlates of bird collisions with buildings across three North American countries.

Collisions with buildings cause up to 1 billion bird fatalities annually in the United States and Canada. However, efforts to reduce collisions would benefit from studies conducted at large spatial scales across multiple study sites with standardized methods and consideration of species- and life-history-related variation and correlates of collisions. We addressed these research needs through coordinated collection of data on bird collisions with buildings at sites in the United States (35), Canada (3), and Mexico (2). We collected all carcasses and identified species. After removing records for unidentified carcasses, species lacking distribution-wide population estimates, and species with distributions overlapping fewer than 10 sites, we retained 269 carcasses of 64 species for analysis. We estimated collision vulnerability for 40 bird species with ≥2 fatalities based on their North American population abundance, distribution overlap in study sites, and sampling effort. Of 10 species we identified as most vulnerable to collisions, some have been identified previously (e.g., Black-throated Blue Warbler [Setophaga caerulescens]), whereas others emerged for the first time (e.g., White-breasted Nuthatch [Sitta carolinensis]), possibly because we used a more standardized sampling approach than past studies. Building size and glass area were positively associated with number of collisions for 5 of 8 species with enough observations to analyze independently. Vegetation around buildings influenced collisions for only 1 of those 8 species (Swainson's Thrush [Catharus ustulatus]). Life history predicted collisions; numbers of collisions were greatest for migratory, insectivorous, and woodland-inhabiting species. Our results provide new insight into the species most vulnerable to building collisions, making them potentially in greatest need of conservation attention to reduce collisions and into species- and life-history-related variation and correlates of building collisions, information that can help refine collision management.

Correlaciones de las Colisiones de Aves contra Edificios en Tres Países de América del Norte Resumen Las colisiones contra los edificios causan hasta mil millones de fatalidades de aves al año en los Estados Unidos y en Canadá. Sin embargo, los esfuerzos por reducir estas colisiones se beneficiarían con estudios realizados a grandes escalas espaciales en varios sitios de estudio con métodos estandarizados y considerando las variaciones relacionadas a la historia de vida y a la especie y las correlaciones de las colisiones. Abordamos estas necesidades de investigación por medio de una recolección coordinada de datos sobre las colisiones de aves contra edificios en los Estados Unidos (35), Canadá (3) y México (2). Recolectamos todos los cadáveres y los identificamos hasta especie. Después de retirar los registros de cadáveres no identificados, las especies sin estimaciones poblacionales a nivel distribución y las especies con distribuciones traslapadas en menos de diez sitios, nos quedamos con 269 cadáveres de 64 especies para el análisis. Estimamos la vulnerabilidad a colisiones para 40 especies con ≥2 fatalidades con base en la abundancia poblacional para América del Norte, el traslape de su distribución entre los sitios de estudio y el esfuerzo de muestreo. De las diez especies que identificamos como las más vulnerables a las colisiones, algunas han sido identificadas previamente (Setophaga caerulescens), y otras aparecieron por primera vez (Sitta carolinensis), posiblemente debido a que usamos una estrategia de muestreo más estandarizada que en los estudios previos. El tamaño del edificio y el área del vidrio estuvieron asociados positivamente con el número de colisiones para cinco de ocho especies con suficientes observaciones para ser analizadas independientemente. La vegetación alrededor de los edificios influyó sobre las colisiones solamente para una de esas ocho especies Catharus ustulatus). Las historias de vida pronosticaron las colisiones; el número de colisiones fue mayor para las especies migratorias, insectívoras y aquellas que habitan en las zonas boscosas. Nuestros resultados proporcionan una nueva perspectiva hacia las especies más vulnerables a las colisiones contra edificios, lo que las pone en una necesidad potencialmente mayor de atención conservacionista para reducir estas colisiones y de estudio de las variaciones relacionadas con la especie y la historia de vida y las correlaciones de las colisiones contra edificios, información que puede ayudar a refinar el manejo de colisiones.

Role of eHealth application Oncokompas in supporting self-management of symptoms and health-related quality of life in cancer survivors: a randomised, controlled trial.

BACKGROUND: Knowledge about the efficacy of behavioural intervention technologies that can be used by cancer survivors independently from a health-care provider is scarce. We aimed to assess the efficacy, reach, and usage of Oncokompas, a web-based eHealth application that supports survivors in self-management by monitoring health-related quality of life (HRQOL) and cancer-generic and tumour-specific symptoms and obtaining tailored feedback with a personalised overview of supportive care options. METHODS: In this non-blinded, randomised, controlled trial, we recruited patients treated at 14 hospitals in the Netherlands for head and neck cancer, colorectal cancer, breast cancer, Hodgkin lymphoma, or non-Hodgkin lymphoma. Adult survivors (aged ≥18 years) were recruited through the Netherlands Cancer Registry (NCR) and invited by their treating physician through the Patient Reported Outcomes Following Initial Treatment and Long term Evaluation of Survivorship (PROFILES) registry. Participants were randomly assigned (1:1) by an independent researcher to the intervention group (access to Oncokompas) or control group (access to Oncokompas after 6 months), by use of block randomisation (block length of 68), stratified by tumour type. The primary outcome was patient activation (knowledge, skills, and confidence for self-management), assessed at baseline, post-intervention, and 3-month and 6-month follow-up. Linear mixed models (intention-to-treat) were used to assess group differences over time from baseline to 6-month follow-up. The trial is registered in the Netherlands Trial Register, NTR5774 and is completed. FINDINGS: Between Oct 12, 2016, and May 24, 2018, 625 (21%) of 2953 survivors assessed for eligibility were recruited and randomly assigned to the intervention (320) or control group (305). Median follow-up was 6 months (IQR 6-6). Patient activation was not significantly different between intervention and control group over time (difference at 6-month follow-up 1·7 [95% CI -0·8-4·1], p=0·41). INTERPRETATION: Oncokompas did not improve the amount of knowledge, skills, and confidence for self-management in cancer survivors. This study contributes to the evidence for the development of tailored strategies for development and implementation of behavioural intervention technologies among cancer survivors. FUNDING: Dutch Cancer Society (KWF Kankerbestrijding).

Coping Strategies and Psychological Symptoms Among Children on St. Thomas in the Aftermath of Hurricanes Irma and Maria.

Research has shown that experiencing a hurricane can lead to internalizing, externalizing, and posttraumatic stress (PTS) symptoms in children. However, the effects of experiencing two hurricanes within a short time frame have not been examined. Moreover, there is limited research examining how children's coping is linked to their psychological functioning and no research using the empirically supported conceptualization of coping that includes primary control coping (i.e., attempts to control the stressor) and secondary control coping (i.e., attempts to adapt to the stressor). This study examined the psychological functioning of 108 children and adolescents (69.7% Black, Non-Hispanic; 56.5% female; M age = 11.59 years, SD = 2.43) in Grades 3-12 as measured 3 months after experiencing Hurricanes Irma and Maria on the island of St. Thomas. Participants completed electronic questionnaires about their demographic characteristics, hurricane exposure (i.e., perceived life-threat, life-threatening events, loss/disruption after hurricanes), coping strategies utilized, and their psychological functioning (i.e., PTS, internalizing, and externalizing symptoms). A principal component analysis of the coping items determined four coping factors: primary control, secondary control, disengagement, and negative coping. Linear regressions, including children's age and aspects of hurricane exposure, found primary control coping was positively associated with PTS symptoms, ß = .18, whereas secondary control coping was negatively associated with PTS and externalizing symptoms, ßs = -.17 and -.19, respectively. Negative coping, but not disengagement coping, was positively associated with all three outcomes, ßs = .31-.42. These findings suggest positive ways children can cope after experiencing a hurricane, informing possible early intervention efforts.

Current research gaps: a global systematic review of HIV and sexually transmissible infections among transgender populations.

Transgender populations are heavily burdened by HIV and other sexually transmissible infections (STIs). However, data on co-infection with HIV and STIs among transgender people are limited. A systematic review was conducted of peer-reviewed articles and conference abstracts between January 2010 and November 2015 that focussed on HIV and STI infections among transgender populations globally. The literature was synthesised and opportunities for improving health research were commented on. Few studies reported HIV-STI co-infection (n=4), while the majority of studies reported HIV and STI infections separately (n=23). Most studies were conducted outside of the USA (n=19), and all but one of these studies reported data on transgender women only. Among USA-based studies (n=8), several reported data on both transgender men and transgender women (n=3), whereas other studies reported exclusively on transgender men (n=1) or transgender women (n=4). Understanding HIV and STIs among transgender people requires research that simultaneously considers multilevel drivers of vulnerabilities. More data are needed on how the interaction of individual determinants, including biological risks of transmission, programmatic determinants such as service-delivery models and policy-level determinants including institutionalised stigma in healthcare settings, influence the HIV- and STI-related outcomes of transgender populations. Leveraging the knowledge of transgender-specific determinants of HIV and STIs should guide the content and approaches to future HIV and STI prevention and treatment efforts.

Neural Versus Gonadal GnIH: Are they Independent Systems? A Mini-Review.

Based on research in protochordates and basal vertebrates, we know that communication across the first endocrine axes likely relied on diffusion. Because diffusion is relatively slow, rapid responses to some cues, including stress-related cues, may have required further local control of axis outputs (e.g., steroid hormone production by the gonads). Despite the evolution of much more efficient circulatory systems and complex nervous systems in vertebrates, production of many "neuro"transmitters has been identified outside of the hypothalamus across the vertebrate phylogeny and these neurotransmitters are known to locally regulate endocrine function. Our understanding of tissue-specific neuropeptide expression and their role coordinating physiological/behavioral responses of the whole organism remains limited, in part, due to nomenclature and historic dogma that ignores local regulation of axis output. Here, we review regulation of gonadotropin-inhibitory hormone (GnIH) across the reproductive axis in birds and mammals to bring further attention to context-dependent disparities and similarities in neuropeptide production by the brain and gonads. We find that GnIH responsiveness to cues of stress appears conserved across species, but that the response of specific tissues and the direction of GnIH regulation varies. The implications of differential regulation across tissues remain unclear in most studies, but further work that manipulates and contrasts function in different tissues has the potential to inform us about both organism-specific function and endocrine axis evolution.

Patterns of bird-window collisions inform mitigation on a university campus.

Bird-window collisions cause an estimated one billion bird deaths annually in the United States. Building characteristics and surrounding habitat affect collision frequency. Given the importance of collisions as an anthropogenic threat to birds, mitigation is essential. Patterned glass and UV-reflective films have been proven to prevent collisions. At Duke University's West campus in Durham, North Carolina, we set out to identify the buildings and building characteristics associated with the highest frequencies of collisions in order to propose a mitigation strategy. We surveyed six buildings, stratified by size, and measured architectural characteristics and surrounding area variables. During 21 consecutive days in spring and fall 2014, and spring 2015, we conducted carcass surveys to document collisions. In addition, we also collected ad hoc collision data year-round and recorded the data using the app iNaturalist. Consistent with previous studies, we found a positive relationship between glass area and collisions. Fitzpatrick, the building with the most window area, caused the most collisions. Schwartz and the Perk, the two small buildings with small window areas, had the lowest collision frequencies. Penn, the only building with bird deterrent pattern, caused just two collisions, despite being almost completely made out of glass. Unlike many research projects, our data collection led to mitigation action. A resolution supported by the student government, including news stories in the local media, resulted in the application of a bird deterrent film to the building with the most collisions: Fitzpatrick. We present our collision data and mitigation result to inspire other researchers and organizations to prevent bird-window collisions.

Diary study of sexual risk taking, alcohol use, and strategies for reducing negative affect in female college students.

OBJECTIVE: The goal of this study was to examine motivations for engaging in risky sexual behaviors (RSBs) and factors that may increase the likelihood of engaging in RSB. RSB was defined as not using condoms during intercourse and having intercourse with poorly known partners, which were treated separately with regard to analyses. METHOD: Utilizing a weekly diary methodology, the present study examined whether using situation-specific coping strategies (e.g, using alcohol to reduce negative affect and sex to reduce negative affect) and whether subjective reports of intoxication significantly predicted if participants would engage in RSB. Female college students (N = 93) completed a weekly computerized questionnaire for 8 weeks reporting on their sexual behavior, their level of intoxication, and use of strategies (i.e., sex and alcohol) to reduce negative affect at the time of the sexual encounter. RESULTS: Using hierarchical linear modeling, results indicated that level of intoxication was the sole significant main effect related to engaging in RSB; specifically, level of intoxication was positively related to sex with a poorly known partner. CONCLUSIONS: Alcohol use, as opposed to motivation for intercourse, is an important area to focus on with regard to prevention of RSB.

Primary non-variceal upper gastrointestinal bleeding in NSAID and low-dose aspirin users: development and validation of risk scores for either medication in two large Dutch cohorts.

BACKGROUND: Non-steroidal anti-inflammatory drugs (NSAIDs) and low-dose acetylsalicylic acid (ASA) have several adverse gastrointestinal (GI) effects, including upper GI bleeding. We aimed to develop a simple risk score to identify high risk NSAID and ASA users for primary upper GI bleeding. METHODS: Using data from two large anonymized health insurance databases, we defined a development and validation cohort with NSAID and ASA users which were followed-up for the occurrence of a primary upper GI bleeding. Cox regression analyses identified risk factors which were combined into simple risk scores. C-statistics were used to evaluate the discriminative ability of these scores in a validation cohort. RESULTS: In total, 421 cases of upper GI bleeding were identified in the initial cohort of 784,263 NSAID users (incidence rate 54.2 per 10,000 person-years), while 1,295 cases of upper GI bleeding were identified in 235,531 ASA users (incidence rate 37.9 per 10,000 person-years). The risk of upper GI bleeding increased with a higher risk score, which for NSAID users included age, male gender, anemia and concomitant use of ASA or anticoagulants. For ASA users, age, anemia, diabetes and concomitant use of other antiplatelet drugs or anticoagulants were included in the risk score. The C-statistics in the validation cohort were 0.68 and 0.63 or NSAID and ASA users, respectively. CONCLUSION: Risk factors for primary upper GI bleeding are to a large extent similar for NSAID and ASA users. Using a risk score based on these risk factors, patients at the highest risk can be identified with moderate accuracy.

Reassessment of the predictive value of the Forrest classification for peptic ulcer rebleeding and mortality: can classification be simplified?

BACKGROUND AND STUDY AIMS: This study aimed to reassess whether the Forrest classification is still useful for the prediction of rebleeding and mortality in peptic ulcer bleedings and, based on this, whether the classification could be simplified. PATIENTS AND METHODS: Prospective registry data on peptic ulcer bleedings were collected and categorized according to the Forrest classification. The primary outcomes were 30-day rebleeding and all-cause mortality rates. Receiver operating characteristic curves were used to test whether simplification of the Forrest classification into high risk (Forrest Ia), increased risk (Forrest Ib-IIc), and low risk (Forrest III) classes could be an alternative to the original classification. RESULTS: In total, 397 patients were included, with 18 bleedings (4.5%) being classified as Forrest Ia, 73 (18.4%) as Forrest Ib, 86 (21.7%) as Forrest IIa, 32 (8.1%) as Forrest IIb, 59 (14.9%) as Forrest IIc, and 129 (32.5%) as Forrest III. Rebleeding occurred in 74 patients (18.6%). Rebleeding rates were highest in Forrest Ia peptic ulcers (59%). The odds ratios for rebleeding among Forrest Ib-IIc ulcers were similar. In subgroup analysis, predicting rebleeding using the Forrest classification was more reliable for gastric ulcers than for duodenal ulcers. The simplified Forrest classification had similar test characteristics to the original Forrest classification. CONCLUSION: The Forrest classification still has predictive value for rebleeding of peptic ulcers, especially for gastric ulcers; however, it does not predict mortality. Based on these results, a simplified Forrest classification is proposed. However, further studies are needed to validate these findings.

Disseminated Cutaneous Mycobacterium chelonae Infection in a Patient With Acute Myeloid Leukemia.

We report a case of disseminated cutaneous Mycobacterium chelonae infection in a patient who was treated with chemotherapy for acute myeloid leukemia. We discuss the clinical manifestations, diagnosis, and treatment of this unusual infection in neutropenic patients.

The direct response of the gonads to cues of stress in a temperate songbird species is season-dependent.

The gonadotropin releasing hormone (GnRH) system in the hypothalamus is often considered the final point in integration of environmental cues as they pertain to the reproductive axis. However, cues such as stress and food availability are detectable in the plasma (as glucocorticoid and metabolic fuel fluctuations). Vertebrate gonads express glucocorticoid receptor, therefore we hypothesized that the gonads can detect and respond directly to cues of stress. We provide evidence here that, in addition to regulation by the brain, the gonads of European starlings (Sturnus vulgaris) respond directly to fluctuations in corticosterone and metabolic fuels by modulating sex steroid secretion. Using a 4-h gonad culture, we show that physiologically-relevant concentrations of corticosterone and metabolic stress (via use of the glucose utilization inhibitor 2-deoxy-D-glucose and the fatty acid oxidation inhibitor ethyl 2-mercaptoacetate (2DG/MA)) can directly decrease testosterone and estradiol secretion from luteinizing hormone and follicle-stimulating hormone (LH/FSH)-stimulated testes and ovaries. This effect is regulated seasonally. Prior to the breeding season, testes and ovaries respond to corticosterone and 2DG/MA by significantly decreasing gonadal steroid release. Within the breeding season, the testes do not respond to these cues of stress, while the ovaries respond only to corticosterone. This seasonal difference in response may be due in part to the influence of these cues of stress on gonadal neuropeptide expression: corticosterone upregulates GnIH expression in the testes while metabolic stress upregulates GnIH in the ovaries. Thus the gonads can directly respond to fluctuations in corticosterone and metabolic fuels during a time of critical importance to the onset of breeding.

Adherence to microsatellite instability testing in young-onset colorectal cancer patients.

BACKGROUND: In 1997, the Bethesda guidelines recommended microsatellite instability testing for colorectal cancer in patients younger than 45 years to screen for Lynch syndrome. In 2004, these guidelines were revised to set the screening age at younger than 50 years. OBJECTIVE: The aim of this study was to investigate to what extent these guidelines were followed in young patients with colorectal cancer in the Mid-Netherlands and to identify the predictors of nonadherence. DESIGN: This is a retrospective cohort study. SETTINGS: This study was conducted in 1 academic and 5 nonacademic hospitals. PATIENTS: All patients diagnosed with colorectal cancer younger than 45 years in the period 1999 to 2004 and younger than 50 years in the period 2005 to 2008 were included. Patients known to be affected by or at risk for Lynch syndrome before diagnosis were excluded. MAIN OUTCOME MEASURES: Patient and tumor characteristics, including microsatellite instability testing results, were collected from the database of the Comprehensive Cancer Center, the National Pathological Archive, participating hospitals, and the regional institute of clinical genetics. Logistic regression analysis was performed to detect a trend in adherence over the years and to identify the predictors of nonadherence. RESULTS: A total of 335 patients were identified. Microsatellite instability testing was performed in 130/335 (39%) patients. Adherence did not improve in the period 1999 to 2008. We found that older age at diagnosis (OR 0.96, 95% CI 0.92-1.00), male sex (OR 0.60, 95% CI 0.38-0.95), and stage IV colorectal cancer (OR 0.45, 95% CI 0.24-0.84) were independent predictors of nonadherence, whereas proximal tumor localization, poor differentiation, and mucinous histology were not. LIMITATIONS: This study was limited by its retrospective design. CONCLUSIONS: Adherence to the Bethesda guidelines in young-onset colorectal cancer is low, particularly in older and male patients and in patients with metastatic disease, which suggests that efforts to improve adherence are needed.

Recording of family history is associated with colorectal cancer stage.

BACKGROUND: Colorectal cancer (CRC) associated with Lynch syndrome usually presents at a relatively young age. The Revised Bethesda Guidelines advise screening for Lynch syndrome in patients diagnosed with CRC and a positive family history (FH) of CRC and other Lynch-related cancers. OBJECTIVE: To evaluate recording of the FH and identify factors associated with recording in young patients with CRC. PATIENTS AND METHODS: In one academic and two nonacademic hospitals, of all patients diagnosed with CRC at the age of 60 years or younger between 1999 and 2007, electronic medical records were evaluated for a recorded FH of CRC and other Lynch-related cancers. Patient and tumor characteristics were retrieved from the Dutch Comprehensive Cancer Centre and the Dutch Pathological Archive. RESULTS: A total of 676 patients were identified. FH was recorded in 395/676 (58%) patients. From 1999 to 2007, recording improved with an odds ratio (OR) of 1.10 [95% confidence interval (CI) 1.03-1.17] per year. Stage III CRC (OR 1.71, 95% CI 1.07-2.75) and administration of chemotherapy (OR 1.84, 95% CI 1.17-2.89) were associated with recording in multivariate analysis. Other factors, including age at diagnosis, sex, surgery, radiotherapy, proximal tumor localization, poor differentiation, and mucinous histology, were not associated with recording. CONCLUSION: A FH of CRC and other Lynch-related cancers was not recorded in ∼40% of young CRC patients and recording improved only slightly over the years. As a first step in the identification of Lynch-related cancer families, physicians should be trained to record a detailed FH in the work-up of all newly diagnosed CRC patients.

Effects of melatonin on peripheral reproductive function: regulation of testicular GnIH and testosterone.

Study of seasonal reproduction has focused on the brain. Here, we show that the inhibition of sex steroid secretion can be seasonally mediated at the level of the gonad. We investigate the direct effects of melatonin on sex steroid secretion and gonadal neuropeptide expression in European starlings (Sturnus vulgaris). PCR reveals starling gonads express mRNA for gonadotropin inhibitory hormone (GnIH) and its receptor (GnIHR) and melatonin receptors 1B (Mel 1B) and 1C (Mel 1C). We demonstrate that the gonadal GnIH system is regulated seasonally, possibly via a mechanism involving melatonin. GnIH/ GnIHR expression in the testes is relatively low during breeding compared with outside the breeding season. The expression patterns of Mel 1B and Mel 1C are correlated with this expression, and melatonin up-regulates the expression of GnIH mRNA in starling gonads before breeding. In vitro, GnIH and melatonin significantly decrease testosterone secretion from LH/FSH-stimulated testes before, but not during, breeding. Thus local inhibition of sex steroid secretion appears to be regulated seasonally at the level of the gonad, by a mechanism involving melatonin and the gonadal GnIH system.

A functional neuropeptide system in vertebrate gonads: Gonadotropin-inhibitory hormone and its receptor in testes of field-caught house sparrow (Passer domesticus).

UNLABELLED: Previously, the expression and action of GnIH (Gonadotropin-inhibitory hormone) has been characterized in the hypothalamus and pituitary, respectively. The action of this neurohormone is to inhibit the synthesis and secretion of luteinizing hormone and follicle-stimulating hormone. Several hormone systems identified in the vertebrate brain and classified as neurohormones are synthesized in and have a localized action on the gonads as well. Here we present several lines of evidence for the expression and action of GnIH and its receptor (GnIHR) in the testis of house sparrow (Passer domesticus). EXPRESSION: Transcripts for GnIH and GnIHR isolated from house sparrow testis were initially identified by PCR, then sequenced and found to be homologous to transcripts from European starling (96% to GnIH, 98% to GnIHR), Gambel's white-crowned sparrow (94% to GnIH) and Japanese quail (90% to GnIHR) brains. Further investigation using in situ hybridization confirmed the presence of GnIH precursor mRNA in the interstitium of the testis and GnIHR mRNA in the interstitium and on spermatocytes. ACTION: The effect of this system on the secretion of testosterone by the testis was investigated using gonadal culture. Testosterone secretion was significantly decreased by 1 microM and 10 microM GnIH in gonadotropin-stimulated testis cultures. In summary, these results indicate the GnIH/GnIHR system is expressed in the testis of house sparrows and its function is to reduce gonadotropin-stimulated testosterone production.

Neuropeptides in the gonads: from evolution to pharmacology.

Vertebrate gonads are the sites of synthesis and binding of many peptides that were initially classified as neuropeptides. These gonadal neuropeptide systems are neither well understood in isolation, nor in their interactions with other neuropeptide systems. Further, our knowledge of the control of these gonadal neuropeptides by peripheral hormones that bind to the gonads, and which themselves are under regulation by true neuropeptide systems from the hypothalamus, is relatively meager. This review discusses the existence of a variety of neuropeptides and their receptors which have been discovered in vertebrate gonads, and the possible way in which such systems could have evolved. We then focus on two key neuropeptides for regulation of the hypothalamo-pituitary-gonadal axis: gonadotropin-releasing hormone (GnRH) and gonadotropin-inhibitory hormone (GnIH). Comparative studies have provided us with a degree of understanding as to how a gonadal GnRH system might have evolved, and they have been responsible for the discovery of GnIH and its gonadal counterpart. We attempt to highlight what is known about these two key gonadal neuropeptides, how their actions differ from their hypothalamic counterparts, and how we might learn from comparative studies of them and other gonadal neuropeptides in terms of pharmacology, reproductive physiology and evolutionary biology.

Effects of exogenous thyroid hormones on visual pigment composition in coho salmon (Oncorhynchus kisutch).

The role of exogenous thyroid hormone on visual pigment content of rod and cone photoreceptors was investigated in coho salmon (Oncorhynchus kisutch). Coho vary the ratio of vitamin A1- and A2-based visual pigments in their eyes. This variability potentially alters spectral sensitivity and thermal stability of the visual pigments. We tested whether the direction of shift in the vitamin A1/A2 ratio, resulting from application of exogenous thyroid hormone, varied in fish of different ages and held under different environmental conditions. Changes in the vitamin A1/A2 visual pigment ratio were estimated by measuring the change in maximum absorbance (lambda max) of rods using microspectrophotometry (MSP). Exogenous thyroid hormone resulted in a long-wavelength shift in rod, middle-wavelength-sensitive (MWS) and long-wavelength-sensitive (LWS) cone photoreceptors. Rod and LWS cone lambda max values increased, consistent with an increase in vitamin A2. MWS cone lambda max values increased more than predicted for a change in the vitamin A1/A2 ratio. To account for this shift, we tested for the expression of multiple RH2 opsin subtypes. We isolated and sequenced a novel RH2 opsin subtype, which had 48 amino acid differences from the previously sequenced coho RH2 opsin. A substitution of glutamate for glutamine at position 122 could partially account for the greater than predicted shift in MWS cone lambda max values. Our findings fit the hypothesis that a variable vitamin A1/A2 ratio provides seasonality in spectral tuning and/or improved thermal stability of visual pigments in the face of seasonal environmental changes, and that multiple RH2 opsin subtypes can provide flexibility in spectral tuning associated with migration-metamorphic events.

The control of reproductive physiology and behavior by gonadotropin-inhibitory hormone.

Gonadotropin-releasing hormone (GnRH) controls the reproductive physiology and behavior of vertebrates by stimulating synthesis and release of gonadotropin from the pituitary gland. In 2000, another hypothalamic neuropeptide, gonadotropin-inhibitory hormone (GnIH), was discovered in quail and found to be an inhibiting factor for gonadotropin release. GnIH homologs are present in the brains of vertebrates, including birds, mammals, amphibians, and fish. These peptides, categorized as RF amide-related peptides (RFRPs), possess a characteristic LPXRF-amide (X = L or Q) motif at their C-termini. GnIH/RFRP precursor mRNA encodes a polypeptide that is possibly cleaved into three mature peptides in birds and two in mammals. The names of these peptides are GnIH, GnIH-related peptide-1 (GnIH-RP-1) and GnIH-RP-2 in birds, and RFRP-1 and RFRP-3 in mammals. GnIH/RFRP is synthesized in neurons of the paraventricular nucleus of the hypothalamus in birds and the dorsomedial hypothalamic area in mammals. GnIH neurons project to the median eminence, thus providing a functional neuroanatomical infrastructure to regulate anterior pituitary function. In quail, GnIH inhibits gonadal activity by decreasing synthesis and release of gonadotropin. The widespread distribution of GnIH/RFRP immunoreactive fibers in all animals tested suggests various actions within the brain. In accordance, GnIH/RFRP receptor mRNA is also expressed widely in the brain and the pituitary. GnIH/RFRP immunoreactive axon terminals are in probable contact with GnRH neurons in birds and mammals, and we recently demonstrated expression of GnIH receptor mRNA in GnRH-I and GnRH-II neurons in European starlings. Thus, GnIH/RFRP may also inhibit gonadotropin synthesis and release by inhibiting GnRH neurons in addition to having direct actions on the pituitary gland. Intracerebroventricular administration of GnIH/RFRP further inhibits reproductive behaviors in songbirds and rodents, possibly via direct actions on the GnRH system. The expression of GnIH/RFRP is regulated by melatonin which is an internal indicator of day length in vertebrates. Stress stimuli also regulate the expression of GnIH/RFRP in songbirds and rodents. Accordingly, GnIH/RFRP may serve as a transducer of environmental information and social interactions into endogenous physiology and behavior of the animal. Recently, it was shown that GnIH/RFRP and its receptor are also expressed in the gonads of birds, rodents and primates. In sum, the existing data suggest that GnIH/RFRP is an important mediator of reproductive function acting at the level of the brain, pituitary, and the gonad in birds and mammals.