Shaped by Their Environment: Variation in Blue Whale Morphology across Three Productive Coastal Ecosystems.

Species ecology and life history patterns are often reflected in animal morphology. Blue whales are globally distributed, with distinct populations that feed in different productive coastal regions worldwide. Thus, they provide an opportunity to investigate how regional ecosystem characteristics may drive morphological differences within a species. Here, we compare physical and biological oceanography of three different blue whale foraging grounds: (1) Monterey Bay, California, USA; (2) the South Taranaki Bight (STB), Aotearoa New Zealand; and (3) the Corcovado Gulf, Chile. Additionally, we compare the morphology of blue whales from these regions using unoccupied aircraft imagery. Monterey Bay and the Corcovado Gulf are seasonally productive and support the migratory life history strategy of the Eastern North Pacific (ENP) and Chilean blue whale populations, respectively. In contrast, the New Zealand blue whale population remains in the less productive STB year-round. All three populations were indistinguishable in total body length. However, New Zealand blue whales were in significantly higher body condition despite lower regional productivity, potentially attributable to their non-migratory strategy that facilitates lower risk of spatiotemporal misalignment with more consistently available foraging opportunities. Alternatively, the migratory strategy of the ENP and Chilean populations may be successful when their presence on the foraging grounds temporally aligns with abundant prey availability. We document differences in skull and fluke morphology between populations, which may relate to different feeding behaviors adapted to region-specific prey and habitat characteristics. These morphological features may represent a trade-off between maneuverability for prey capture and efficient long-distance migration. As oceanographic patterns shift relative to long-term means under climate change, these blue whale populations may show different vulnerabilities due to differences in migratory phenology and feeding behavior between regions. Spanish abstract La ecología y patrones de historia de vida de las especies a menudo se reflejan en la morfología animal. Las ballenas azules están distribuidas globalmente, con poblaciones separadas que se alimentan en diferentes regiones costeras productivas de todo el mundo. Por lo tanto, brindan la oportunidad de investigar cómo las características regionales de los ecosistemas pueden impulsar diferencias morfológicas dentro de una especie. Aquí, comparamos la oceanografía física y biológica de tres zonas de alimentación diferentes de la ballena azul: (1) Bahía de Monterey, California, EE. UU., (2) Bahía del sur de Taranaki (BST), Nueva Zelanda, y (3) Golfo de Corcovado, Chile. Adicionalmente, comparamos la morfología de las ballenas azules de estas regiones utilizando imágenes de aeronaves no tripuladas. La Bahía de Monterey y el Golfo de Corcovado son estacionalmente productivos y apoyan la estrategia migratoria de la historia de vida de las poblaciones de ballena azul chilena y del Pacífico Norte Oriental (PNO), respectivamente. Por el contrario, la población de ballena azul de Nueva Zelanda permanece en la menos productiva BST durante todo el año. Las tres poblaciones eran indistinguibles en cuanto a la longitud corporal total. Sin embargo, las ballenas azules de Nueva Zelanda tenían una condición corporal significativamente mayor a pesar de una menor productividad regional, potencialmente atribuible a su estrategia no migratoria que facilita un menor riesgo de desalineación espaciotemporal con oportunidades de alimentación disponibles de manera más consistente. Alternativamente, la estrategia migratoria de las poblaciones de ballenas PNO y chilena puede tener éxito cuando su presencia en las zonas de alimentación se alinea temporalmente con la abundante disponibilidad de presas. Documentamos diferencias en la morfología del cráneo y la aleta caudal entre poblaciones, que pueden estar relacionadas con diferentes comportamientos de alimentación adaptados a las características de hábitat y presas específicas para cada región. Estas características morfológicas pueden representar una compensación entre la maniobrabilidad para la captura de presas y una migración eficiente a larga distancia. A medida que los patrones oceanográficos cambian en términos de mediano a largo plazo debido al cambio climático, estas poblaciones de ballenas azules pueden mostrar diferentes vulnerabilidades debido a diferencias en la fenología migratoria y el comportamiento de alimentación entre regiones.

Epidemiology, clinical features and outcomes of incident tuberculosis in children in Canada in 2013-2016: results of a national surveillance study.

PURPOSE: Childhood tuberculosis disease is difficult to diagnose and manage and is an under-recognised cause of morbidity and mortality. Reported data from Canada do not focus on childhood tuberculosis or capture key epidemiologic, clinical and microbiologic details. The purpose of this study was to assess demographics, presentation and clinical features of childhood tuberculosis in Canada. METHODS: We conducted prospective surveillance from 2013 to 2016 of over 2700 paediatricians plus vertical tuberculosis programmes for incident tuberculosis disease in children younger than 15 years in Canada using the Canadian Paediatric Surveillance Program (CPSP). RESULTS: In total, 200 cases are included in this study. Tuberculosis was intrathoracic in 183 patients of whom 86% had exclusively intrathoracic involvement. Central nervous system tuberculosis occurred in 16 cases (8%). Fifty-one per cent of cases were hospitalised and 11 (5.5%) admitted to an intensive care unit. Adverse drug reactions were reported in 9% of cases. The source case, most often a first-degree relative, was known in 73% of cases. Fifty-eight per cent of reported cases were Canadian-born Indigenous children. Estimated study rates of reported cases (per 100 000 children per year) were 1.2 overall, 8.6 for all Indigenous children and 54.3 for Inuit children. CONCLUSION: Childhood tuberculosis may cause significant morbidity and resource utilisation. Key geographies and groups have very high incidence rates. Elimination of childhood tuberculosis in Canada will require well-resourced community-based efforts that focus on these highest risk groups.

Dedicated orthogeriatric service reduces hip fracture mortality.

BACKGROUND: Hip fracture is a common serious injury afflicting the geriatric population and is associated with poor clinical outcomes, functional and walking disabilities and high 1-year mortality rates. A multidisciplinary approach has been shown to improve outcomes of geriatric patients with fragility fracture. AIMS: We piloted a dedicated orthogeriatric service for hip fracture patients to determine if the service facilitated a change in major patient outcomes, such as mortality, length of stay and dependency. METHODS: A dedicated orthogeriatrics service for hip fracture was established as a collaborative project between the Department of Geriatric Medicine and Department of Orthopaedic Surgery at a university teaching hospital. Orthogeriatrics service data were collected prospectively on an orthogeriatric filemaker database from July 2011 to July 2012 (N = 206). Data were compared to previously recorded data (Irish Hip Fracture Database) on a cohort of hip fracture patients admitted to the same orthopaedic trauma unit from July 2009 to July 2010 (N = 248). RESULTS: Patients in the orthogeriatric service group experienced significant reductions in 1-year mortality (χ2 = 13.34, P < 0.001), length of acute hospital stay (U = -3.77, P < 0.001) and requirements for further rehabilitation (χ 2 = 26.59, P < 0.001). Patients in the pre-service establishment group were significantly more dependent following their fracture than the patients in the orthogeriatric service group (χ 2 = 5.34, P = 0.021). CONCLUSIONS: A multidisciplinary management approach to fragility fracture of the femoral neck that involves comprehensive geriatric assessment, daily medical involvement of a geriatric team and specialised follow-up assessment leads to a significant reduction in mortality and improved outcomes.

In vitro maturation is associated with increased early embryo arrest without impairing morphokinetic development of useable embryos progressing to blastocysts.

STUDY QUESTIONS: Does polycystic ovarian syndrome (PCOS) or in vitro maturation (IVM) treatment affect embryo development events and morphokinetic parameters after time-lapse incubation? SUMMARY ANSWER: There was an increase in some abnormal phenotypic events in PCOS-IVM embryos as well as an increase in early arrest of PCOS-IVM and PCOS-ICSI embryos; however, IVM treatment or PCOS status did not alter morphokinetic development of embryos suitable for transfer of vitrification. WHAT IS KNOWN ALREADY: IVM has been less successful than standard IVF in terms of clinical pregnancy, implantation and live birth rates. There is currently no information available about the development of IVM embryos according to time-lapse analysis. STUDY DESIGN, SIZE AND DURATION: This article represents a prospective case-control study. The study involved 93 participants who underwent 93 treatment cycles. Cycles were completed between January 2013 and July 2014. PARTICIPANTS/MATERIALS, SETTING AND METHODS: Participants were recruited for the study at Fertility Specialists of WA and Fertility Specialists South, Perth, Western Australia. Of the PCOS diagnosed patients, 32 underwent IVM treatment (PCOS-IVM) and 23 had standard ICSI treatment (PCOS-ICSI). There were 38 patients without PCOS who underwent standard ICSI treatment comprising the control group (control-ICSI). MAIN RESULTS AND THE ROLE OF CHANCE: The PCOS-IVM group showed significantly more embryos with multinucleated two cells (P = 0.041), multinucleated four cells (P = 0.001) and uneven two cells (P = 0.033) compared with the control-ICSI group, but not the PCOS-ICSI group. There were no significant differences in the rates of any abnormal events between the PCOS-ICSI and control-ICSI groups. Embryo arrest between Days 2 and 3 was higher in the PCOS-IVM and PCOS-ICSI groups compared with the control-ICSI group (P < 0.001 and P = 0.001). Embryo arrest from Days 3 to 4 was higher in the PCOS-IVM group compared with both the PCOS-ICSI and control-ICSI groups (P < 0.001). There were no differences in embryo arrest rates across all three groups at the compaction or blastulation stages. Cumulative rates of embryo arrest, from the time to second polar body extrusion (tPB2) to the time to formation of a blastocyst (tB), result in a decreased proportion of useable PCOS-IVM blastocysts compared with the other two treatment groups; however, of the embryos remaining, there was no significant difference in morphokinetic development between the three groups. LIMITATIONS AND REASONS FOR CAUTION: This was a small study using time-lapse analysis of embryo development as the primary end-point. Larger, randomized, clinical trials are required to clarify the implications of time-lapse incubation of IVM embryos and the effects on implantation and ongoing pregnancy. WIDER IMPLICATIONS OF THE FINDINGS: This is the first study to compare the time-lapse analysis of IVM with standard ICSI for patients with and without PCOS. This allows for a more detailed and specific timeline of events from embryos generated using this approach for patients diagnosed with PCOS and shows that embryos generated from IVM have an increased rate of early embryo arrest, however; morphokinetic development is not impaired in embryos that progress to the useable blastocyst stage. STUDY FUNDING/COMPETING INTERESTS: The study was supported by the Women's and Infant's Research Foundation of Western Australia. R.H. is the Medical Director of Fertility Specialists of Western Australia and a shareholder in Western IVF. He has received educational sponsorship from MSD, Merck-Serono and Ferring Pharmaceuticals. The other authors have no competing interests.

Predicting mortality following hip fracture: an analysis of comorbidities and complications.

BACKGROUND: Hip fracture is common in the geriatric population. These patients have multiple comorbidities that complicate treatment and recovery such that poor functional outcomes often result. Since functional outcomes are associated with comorbidities and complications it is important to define the contributing factors. AIMS: To describe comorbidities common to geriatric hip fracture patients and determine predictability of complications and mortality based on comorbidities. METHODS: Data in this study were sourced from information prospectively collected for evaluation of a new orthogeriatric service established at a University Teaching Hospital over the period of 1 year. RESULTS: The median age was 82 years (range 54-100) and 73 % were female (N = 206). Common comorbidities included hypertension (51 %), dementia (28 %), osteoporosis (19 %), ischaemic heart disease (IHD) (15 %) and chronic obstructive pulmonary disease (15 %). In predicting 1-year mortality based on comorbidities, the final model included age, IHD, delay to surgery and explained 26 % of the variability in mortality. Predicting 1-year mortality based on complications, the final model included age and respiratory complications and explained 26 % of the variability in mortality. There was a significant association between having respiratory complications and chronic obstructive pulmonary disease (p < 0.001) with 63 % of those with respiratory complications having chronic obstructive pulmonary disease. CONCLUSIONS: This study highlights specific patient comorbidities and medical complications that could be used to guide clinical assessment, management and targeted interventions that improve outcomes in this patient group.

The Community Assessment of Risk Instrument: Investigation of Inter-Rater Reliability of an Instrument Measuring Risk of Adverse Outcomes.

BACKGROUND: Frailty is increasingly common in community dwelling older adults and increases their risk of adverse outcomes. Risk assessment is implicit in the Aged Care Assessment Teams process, but few studies have considered the factors that influence the assessor's decision making or explored the factors that may contribute to their interpretation of risk. OBJECTIVE: to examine the inter-rater reliability of the Community Assessment of Risk Instrument (CARI), which is a new risk assessment instrument. DESIGN: A cohort study was used. SETTING AND PARTICIPANTS: A sample of 50 community dwelling older adults underwent comprehensive geriatric assessment by two raters: a geriatrician and a registered nurse. Procedure and measurements: Each participant was scored for risk by the two raters using the CARI. This instrument ranks risk of three adverse outcomes, namely i) institutionalisation, ii) hospitalisation and iii) death within the next year from a score of 1, which is minimal risk to 5, which is extreme risk. Inter-rater reliability was assessed with Gamma, Spearman correlation and Kappa statistics. Internal consistency was assessed with Cronbach's alpha. RESULTS: There were 30 female (mean age 82.23 years) and 20 male (mean age 81.75 years) participants. Items within domains showed good-excellent agreement. The gamma statistic was >0.77 on 6/7 Mental State items, 14/15 items in the Activities of Daily Living domain. In the Medical domain, 6/9 items had Gamma scores >0.80. The global domain scores correlated well, 0.88, 0.72 and 0.87. Caregiver network scores were 0.71, 0.73 and 0.51 for the three domains. Inter-rater reliability scores for global risk scales were 0.86 (institutionalisation) and 0.78 (death). The gamma statistic for hospitalisation was 0.29, indicative of lower inter-rater reliability. Cronbach's alpha was 0.86 and 0.83 for the Activities of Daily Living domain, 0.51 and 0.42 for the Mental state domain and 0.23 and 0.10 for the Medical state domain. CONCLUSIONS: Overall, the instrument shows good inter-rater reliability. Poor correlations on some items relate to poor communication of clinical data and variable interpretation based on professional background. Lack of internal consistency in the medical condition domain confirms the discrete nature of these variables.

In vitro maturation as an alternative to standard in vitro fertilization for patients diagnosed with polycystic ovaries: a comparative analysis of fresh, frozen and cumulative cycle outcomes.

STUDY QUESTION: Is in vitro maturation (IVM) as successful as standard in vitro fertilization (IVF) for the treatment of patients with polycystic ovaries (PCO) in terms of fresh, frozen and cumulative pregnancy outcomes? SUMMARY ANSWER: There was no difference in clinical pregnancy rates in fresh or frozen embryo transfer (FET) cycles between the two treatment groups however, the IVM group showed a lower clinical pregnancy rate cumulatively. There was significantly fewer live births resulting from IVM treatment for both fresh and cumulative cycle outcomes however, there was no difference in live birth rates resulting from FETs between IVM and IVF treatment. WHAT IS KNOWN ALREADY: IVM is well recognized as the only treatment option to eliminate completely the incidence of ovarian hyperstimulation syndrome. However, historically IVM has been less successful than standard IVF in terms of clinical pregnancy, implantation and live birth rates. STUDY DESIGN, SIZE, AND DURATION: This paper represents a retrospective case-control study. The study involved 121 participants who underwent 178 treatment cycles. Cycles were completed between March 2007 and December 2012. All fresh cycles and subsequent FET cycles were included in the analysis to calculate cumulative outcomes. PARTICIPANTS/MATERIALS, SETTING, AND METHODS: All participants were prospectively diagnosed with PCO morphology or polycystic ovarian syndrome (PCOS) and underwent either IVM or standard IVF treatment. Their treatment outcomes were analysed with regard to embryological data, and the rate of biochemical pregnancy, clinical pregnancy and live birth, in addition maternal and neonatal outcomes were assessed. Fifty-six patients underwent 80 cycles of IVM treatment and 65 patients underwent 98 cycles of standard IVF treatment. MAIN RESULTS AND THE ROLE OF CHANCE: For fresh cycles, the differences in the biochemical pregnancy, clinical pregnancy or miscarriage rates between the two treatment groups were not statistically significant. The IVM group showed significantly lower live birth rates in fresh cycles in comparison to standard IVF treatment (18.8 versus 31.0%, P = 0.021). For frozen embryo transfer (FET) cycles the differences in biochemical pregnancy, clinical pregnancy, live birth or miscarriage rates between the two treatments groups were not statistically significant. The cumulative biochemical pregnancy (67.5 versus 83.7%, P = 0.018), clinical pregnancy (51.3 versus 65.3%, P = 0.021) and live birth rates (41.3 versus 55.1%, P = 0.005) were significantly lower in the IVM group in comparison to the standard IVF treatment group. There was no overall difference in the cumulative miscarriage rates between the two treatment groups. There was no difference between treatment methods with regard to the neonatal outcomes, and the IVM group had a significantly lower rate of ovarian hyperstimulation syndrome (0 versus 7.1%, P < 0.001). LIMITATIONS, REASONS FOR CAUTION: This was an observational study and further randomized clinical trials are required to clarify the difference in outcomes between standard IVF and IVM for patients with PCO/PCOS. WIDER IMPLICATIONS OF THE FINDINGS: This is the first study to compare IVM with standard IVF in PCO/PCOS patients using blastocyst development and single embryo transfer. Furthermore, it is the first study to show the results of fresh, frozen and cumulative treatment cycle outcomes between the two groups. Our results show similar success rates to those reported from other groups, particularly in relation to the incidence of miscarriage in fresh IVM cycles and improved success from FET cycles. Maternal and neonatal outcomes are consistent with the limited literature available. STUDY FUNDING/COMPETING INTERESTS: The study was supported by the Women's and Infant's Research Foundation of Western Australia. Professor Hart is Medical Director of Fertility Specialists of Western Australia (FSWA) and a shareholder Western IVF. He has received educational sponsorship from MSD, Merck-Serono and Ferring Pharmaceuticals. T.H. is a consultant with FSWA and a shareholder in Western IVF. She has received educational sponsorship from MSD, Merck-Serono and Ferring Pharmaceuticals. The other authors have no competing interests.

IVF versus ICSI for the fertilization of in-vitro matured human oocytes.

Traditional dogma suggests that intracytoplasmic sperm injection (ICSI) should be performed to ensure successful oocyte fertilization in an in-vitro maturation (IVM) cycle. This study postulated that there would be no difference in the fertilization rate when ICSI was compared with IVF. This hypothesis was tested in a randomized trial of IVF versus ICSI in IVM. A total of 150 immature oocytes were collected in eight cycles of IVM for patients diagnosed with polycystic ovarian syndrome (PCOS). Patients were primed with minimal FSH before transvaginal oocyte aspiration. Sibling oocytes were inseminated by 50% IVF and 50% ICSI. There was no significant difference in fertilization, useable or total blastocyst development between the two insemination technique groups. Clinical pregnancy results for combined fresh and cryopreserved transfers were identical between the two insemination techniques with a total of two fresh and five cryopreserved IVF-inseminated embryos resulting in three clinical pregnancies (42.9%) and five fresh and two cryopreserved ICSI-derived embryos resulting in three clinical pregnancies (42.9%). This research has shown IVF to be a legitimate fertilization technique for IVM oocytes in PCOS patients and provides a greater awareness of the use of a fertilization method previously not utilized with IVM. In-vitro maturation (IVM) is an alternative treatment method to traditional IVF. Due to the minimal use of stimulating hormones in this treatment, IVM has a lower risk of ovarian hyperstimulation syndrome, it can be used for fertility preservation in cancer patients and it is more cost conservative. Early research into the effects of IVM showed a hardening effect on the membrane surrounding the egg (the zona pellucida). It was initially believed that, to overcome this hardening in order to allow the egg to be fertilized, spermatozoa would need to be injected into the egg using intracytoplasmic sperm injection. Due to recent advances in hormonal stimulation protocols (FSH priming) and culture conditions, we postulated that, for patients suffering from polycystic ovarian syndrome (PCOS), fertilization, embryo development and clinical pregnancy would not be superior in the injected oocytes compared with those inseminated by IVF. We found that by using the two insemination techniques on sibling oocytes from eight PCOS patients, there was no significant difference in fertilization, useable or total blastocyst development (day 5 or 6 embryos) and that clinical pregnancy results were identical. This research provides a greater awareness of a fertilization technique which is not normally utilized for IVM treatment, providing a less invasive, more cost-effective approach for the patient.

In vitro developmental potential of macaque oocytes, derived from unstimulated ovaries, following maturation in the presence of glutathione ethyl ester.

BACKGROUND: The inadequacies of oocyte in vitro maturation (IVM) systems for both non-human primates and humans are evidenced by reduced fertilization and poor embryonic development, and may be partly explained by significantly lower glutathione (GSH) contents compared with in vivo matured (IVO) oocytes. As this influence has not been fully explored, this study investigated the effect of the GSH donor, glutathione ethyl ester (GSH-OEt), on the IVM and development of macaque oocytes as a model of human oocyte IVM. METHODS: Macaque oocytes derived from unstimulated ovaries were cultured in mCMRL-1066 alone or supplemented with 3 or 5 mM GSH-OEt. In vitro matured oocytes were subjected to the GSH assay, fixed for the assessment of spindle morphology or prepared ICSI. Embryo development of zygotes cultured in mHECM-9 was assessed up to Day 9 post-ICSI. RESULTS Supplementation of the maturation medium with GSH-OEt significantly increased oocyte maturation and normal fertilization rates compared with control oocytes, but only 5 mM GSH-OEt significantly increased the oocyte and cumulus cell GSH content. Confocal microscopy revealed significant differences in the spindle morphology between IVO and control in vitro matured metaphase II oocytes. Oocytes matured with 5 mM GSH-OEt exhibited spindle area and spindle pole width similar to that seen in the IVO oocyte. While no significant differences were observed in blastocyst rates, addition of 3 mM GSH-OEt during IVM significantly increased the proportion of embryos developing to the 5-8 cell stage while 5 mM GSH-OEt significantly increased the proportion of morula-stage embryos compared with controls. CONCLUSIONS: Supplementation of the IVM medium with GSH-OEt promotes better maturation and normal fertilization of macaque oocytes compared with non-supplemented medium. However, further improvement of the primate oocyte IVM culture system is required to support better blastocyst development of oocytes derived from unstimulated ovaries.

Oocyte glutathione and fertilisation outcome of Macaca nemestrina and Macaca fascicularis in in vivo- and in vitro-matured oocytes.

Fertilisation and development of IVM non-human primate oocytes is limited compared with that of in vivo-matured (IVO) oocytes. The present study describes the IVM of macaque oocytes with reference to oocyte glutathione (GSH). Timing of maturation, comparison of IVM media and cysteamine (CYS) supplementation as a modulator of GSH were investigated. A significantly greater proportion of oocytes reached MII after 30 h compared with 24 h of IVM. Following insemination, IVM oocytes had a significantly lower incidence of normal fertilisation (i.e. 2PN = two pronuclei and at least one polar body) and a higher rate of abnormal fertilisation (1PN = one pronucleus and at least one polar body) compared with IVO oocytes. Immunofluorescence of 1PN zygotes identified incomplete sperm head decondensation and failure of male pronucleus formation as the principal cause of abnormal fertilisation in IVM oocytes. The IVO oocytes had significantly higher GSH content than IVM oocytes. Cumulus-denuded oocytes had significantly lower GSH following IVM compared with immature oocytes at collection. Cysteamine supplementation of the IVM medium significantly increased the GSH level of cumulus-intact oocytes and reduced the incidence of 1PN formation, but did not improve GSH levels of the denuded oocyte. Suboptimal GSH levels in macaque IVM oocytes may be related to reduced fertilisation outcomes.

Developmental potential of bovine oocytes following IVM in the presence of glutathione ethyl ester.

Glutathione (GSH) is synthesised during oocyte maturation and represents the oocyte's main non-enzymatic defence against oxidative stress. Inadequate defence against oxidative stress may be related to poor embryo quality and viability. In the present study, bovine oocytes were matured in vitro in the presence of GSH ethyl ester (GSH-OEt), a cell permeable GSH donor, and its effects on subsequent fertilisation and embryo development were assessed. GSH-OEt significantly increased the GSH content of IVM oocytes without affecting fertilisation or Day 3 cleavage rates. Maturation in the presence of GSH-OEt did not significantly increase the blastocyst rate compared with control oocytes. However, 5 mM GSH-OEt treatment resulted in significantly higher blastocyst total cell number. The GSH level of IVM oocytes was significantly decreased in the absence of cumulus cells and when cumulus-oocyte complexes were cultured in the presence of buthionine sulfoximine (BSO), an inhibitor of GSH synthesis. The addition of GSH-OEt to cumulus-denuded or BSO-treated oocytes increased the GSH content of bovine oocytes and restored the rate of normal fertilisation, but not embryo development, to levels seen in control oocytes. Thus, GSH-OEt represents a novel approach for effective in vitro elevation of bovine oocyte GSH and improvement in blastocyst cell number.

Effects of the selective serotonin reuptake inhibitor, fluoxetine, on regional gastric contractility.

UNLABELLED: Selective serotonin reuptake inhibitors (SSRIs) are increasingly used to treat a variety of disorders but have gastrointestinal side-effects. AIM: To determine the effects of the SSRI, fluoxetine, on gastric smooth muscle contractility. METHODS: Fundic, antral, and pyloric circular muscle contractility of guinea pig muscle strips were measured in vitro. Fluoxetine was added in concentrations from 0.1 nmol L(-1) to 100 mumol L(-1). Receptor antagonists were used to determine the neural pathways involved. RESULTS: Fluoxetine caused concentration dependent contractions, which were greatest in fundus compared with the antrum or pylorus. The contractile effects of fluoxetine in the antrum were reduced by tetrodotoxin, atropine, phentolamine, and the 5-HT(4) receptor antagonist GR 113808. The contractile effects of fluoxetine in the fundus were reduced by atropine, phentolamine, and GR 113808. CONCLUSIONS: Fluoxetine affects gastric contractility with regional variability - contracting the fundus more than the antrum or pylorus. The fluoxetine contractile effect is reduced by tetrodotoxin, atropine, phentolamine, and a 5-HT(4) receptor antagonist. These results suggest fluoxetine interacts with muscarinic, alpha-adrenergic, and serotoninergic receptors and/or ongoing reuptake/release of serotonin in the stomach.

Glycosidase activity in the excretory-secretory products of the liver fluke, Fasciola hepatica.

Fasciola hepatica secretes proteolytic enzymes and other molecules that are essential for host penetration and migration. This mixture may include enzymes required for the degradation of supramucosal gels, which defend epithelial surfaces against pathogen entry. These contain hydrated mucins that are heavily glycosylated. Excretory-secretory products (ES) from F. hepatica were examined for a range of glycosidase activities, using synthetic 4-methylumbelliferyl glycosides as substrates. The ES product contained at least 8 different glycosidase activities, the most abundant of which were beta-N-acetylhexosaminidase, beta-galactosidase and beta-glucosidase. Alpha-fucosidase, beta-glucuronidase, alpha-galactosidase, alpha-mannosidase and neuraminidase were also present. Beta-N-acetylhexosaminidase and beta-galactosidase were present in multiple isoforms (at least 4), whereas beta-glucosidase appeared to exist as one isoenzyme with a pI < 3.8. All three enzymes had acidic pH optima (4.5-5.0). Ovine small intestinal mucin was degraded by ES at pH 4.5 or 7.0, with or without active cathepsin L, the major protease found in F. hepatica ES. The ability of F. hepatica ES to degrade mucin in the presence or absence of active cathepsin L suggests that cathepsin L is not essential for mucin degradation. The abundance of beta-galactosidase and beta-hexosaminidase in ES supports a role for these enzymes in mucin degradation.

Effects of clonidine and tricyclic antidepressants on gastric smooth muscle contractility.

To determine if and how clonidine and tricyclic antidepressants affect gastric contractility. Guinea pig fundic and antral circular muscle strips were studied in vitro. The effects of clonidine or amitriptyline added in graded concentrations on contractions to electric field stimulation (EFS), acetylcholine (ACh), and SP in the presence of N(epsilon)-nitro-l-arginine methyl ester (l-NAME) were studied. EFS produced frequency dependent contractions of fundic and antral muscle that were abolished by atropine or tetrodotoxin (TTX). ACh contractions were abolished by atropine but not TTX. Clonidine reduced contractile response to EFS but had no effect on ACh contractions. The threshold concentration of clonidine to inhibit EFS contractions was lower in the fundus than in the antrum. Amitriptyline reduced contractions to both EFS and ACh but not to SP. The threshold concentration of amitriptyline to inhibit EFS contractions was lower in the antrum than in the fundus. Both clonidine and amitriptyline affect gastric contractility. At threshold concentrations, clonidine affects fundic contractility whereas amitriptyline affects antral contractility. Clonidine affects gastric contractility in response to EFS but not to ACh, suggesting alpha-2 receptors on cholinergic nerves that reduce ACh release. Amitriptyline inhibits gastric contractility to EFS and ACh suggesting an inhibitory muscle effect.

The cytoplasmic linker protein CLIP-170 is a human autoantigen.

The purpose of this study was to identify autoantigens that are recognized by human sera and are associated with a speckled cytoplasmic fluorescent staining pattern on tissue culture cells, and to determine clinical features associated with specific autoantibodies. A serum from a patient with systemic lupus erythematosus was used to identify a 3.7-kb cDNA insert from a HeLa cell expression library. The purified cDNA (VLK2.1) encoded a peptide of 1051 amino acids that shared 98.4% similarity with the carboxyl terminal portion of a previously reported 170 kD protein named cytoplasmic linker protein-170 (CLIP-170). Antibodies affinity purified with the recombinant CLIP-170 protein, the prototype human serum and a monoclonal antibody raised against CLIP-170 exhibited identical speckled staining of the cytoplasm in HEp-2 cells. The human autoantibodies reacted with the purified recombinant protein in a Western immunoblot and immunoprecipitated the in vitro translated recombinant protein. Three additional human sera also immunoprecipitated the recombinant CLIP-170 protein. The clinical diagnoses in these patients were limited scleroderma, glioblastoma and idiopathic pleural effusion. This is the first report that identifies CLIP-170 as a human autoantigen.

An unusual subcellular localization of GLUT1 and link with metabolism in oocytes and preimplantation mouse embryos.

Although mouse oocytes and cleavage-stage embryos prefer pyruvate and lactate for metabolic fuels, they do take up and metabolize glucose. Indeed, presentation of glucose during the cleavage stages is required for subsequent blastocyst formation, which normally relies on uptake and metabolism of large amounts of glucose. Expression of the facilitative glucose transporter GLUT1 was examined using immunohistochemistry and Western blotting, and in polyspermic oocytes, metabolism of glucose was measured and compared with that of pyruvate and glutamine. GLUT1 was observed in all oocytes and embryos, and membrane and vesicular staining was present. Additionally, however, in polyspermic oocytes, the most intense staining was in the pronuclei, and this nuclear staining persisted in cleaving normal embryos. Furthermore, GLUT1 expression appeared to be up-regulated both in nuclei and plasma membranes following culture of oocytes in the absence of glucose. In polyspermic oocytes, the metabolism of glucose, but not of pyruvate or glutamine, was directly proportional to the number of pronuclei formed. After compaction, nuclear staining diminished, and GLUT1 localized to basolateral membranes of the outer cells and trophectoderm. In blastocysts, a weak but uniform staining of inner-cell-mass plasma membranes was apparent. The results are discussed in terms of potential roles for GLUT1 in pronuclei of oocytes and zygotes, nuclei of cleavage-stage embryos, and a transepithelial transport function for GLUT1, probably coupled with GLUT3, in compacted embryos and blastocysts.

Myosin light chain phosphorylation correlates with contractile force in guinea pig gallbladder muscle.

Acetylcholine (ACh)-induced gallbladder smooth muscle contraction involves myosin light chain phosphorylation (MLCP). ACh-induced contraction is dose dependent. Whether MLCP by ACh is also dose dependent and how it correlates with contractile force have not been carefully evaluated. This study investigated the correlation between gallbladder muscle contraction and MLCP. Guinea pig gallbladder muscle strips were studied isometrically and frozen after different doses of ACh (0, 0.1, 5, 100 microM) for different periods of incubation (0.5, 1, 2, 3, 4 min). MLCP was determined using gel electrophoresis. Both contraction and MLCP in response to ACh were concentration dependent. Peak MLCP to ACh 100 microM occurred at 30 sec. There was a high correlation between active force and MLCP (r = 0.991; P = 0.009 at 30 sec stimulation). Nifedipine 1 microM reduced ACh-induced contraction and MLCP by a similar degree (31% and 33%, respectively). In conclusion, gallbladder contractile force significantly correlates with MLCP. This is consistent with the hypothesis that initiation of gallbladder cholinergic contraction is dependent on phosphorylation of myosin light chains.

Effect of indomethacin on gallbladder inflammation and contractility during acute cholecystitis.

OBJECTIVE: The aim of this study was to determine whether the prostaglandin synthase inhibitor indomethacin reverses the inflammation and abnormal gallbladder contractility that occur after common bile duct ligation (CBDL), a model of acute cholecystitis. METHODS: Gallbladder muscle contractility was studied in vitro in normal, CBDL, and sham-operated guinea pigs. Animals were treated with saline or indomethacin in vivo. Acetylcholine (ACh) was used to directly contract the muscle and electric field stimulation (EFS) to activate intrinsic nerves. Hematoxylin and eosin-stained slides of muscle strips were scored for inflammation. RESULTS: CBDL in saline-treated animals increased the inflammation score and decreased gallbladder muscle contractility to ACh and EFS. Indomethacin decreased the inflammation score and partly reversed the smooth muscle contractile response to ACh 6 and 24 h after CBDL, but not at 48 h. Indomethacin did not reverse the CBDL-induced decrease in nerve-evoked contractions. CONCLUSION: Gallbladder inflammation and contractile dysfunction after CBDL are partly reversed with indomethacin at 6 and 24 h, but not at 48 h. This suggests that, early in the course of CBDL, the inflammation and contractile dysfunction are, in part, prostaglandin-mediated.

The contractile action of platelet-activating factor on gallbladder smooth muscle.

Platelet-activating factor (PAF) may be a mediator of some sequelae of cholecystitis, a disorder with gallbladder motor dysfunction. The aims of this study were to determine the effect and mechanism of PAF on gallbladder muscle. Exogenous administration of PAF-16 or PAF-18 caused dose-dependent contractions of gallbladder muscle strips in vitro with threshold doses of 1 ng/ml and 10 ng/ml, respectively. The PAF-induced contractions were not significantly reduced by TTX, atropine, or hexamethonium but were significantly inhibited with the PAF receptor antagonists ginkolide B and CV-3988. The PAF-induced contraction was reduced by indomethacin. Preventing influx of extracellular calcium with a calcium-free solution nearly abolished the PAF contractile response. Nifedipine inhibited the PAF contractile response, whereas ryanodine had no effect. Pertussis toxin reduced the PAF contractile response. In conclusion, PAF causes gallbladder contraction through specific PAF receptors on gallbladder muscle. These PAF receptors appear to be linked to a prostaglandin-mediated mechanism and to pertussis toxin-sensitive G proteins. The contractile response is largely mediated through the utilization of extracellular calcium influx through voltage-dependent calcium channels.