Practice guidelines for intramuscular injection in mental health: A delphi method

Introduction

Intramuscular injections (IMI) remain a frequent practice in mental health. The available guidelines for IMI in mental health only focus on the technical side of the practices. Moreover, no recent update has been performed to improve practice of IMI in mental health

Objectives

To assess a formalized consensus agreement regarding the best practice concerning IMI in mental health and to develop practice guidelines.

Methods

A two-round Delphi method was used. The scientific committee consisted in one psychiatrist, one orthopaedic surgeon, one infection control practitioner, one hospital pharmacist, one mental health nurse, one nurse exploring care relationship and one nurse educator. From literature review, each expert proposed specific recommendations. The panel experts were asked to rate the appropriateness and the applicability in current practice of each recommendation on a 9-point Likert scale. Panel members were recruited in five mental health institutions. The first round questionnaire was emailed to each respondent on February 2020 and the second one on June. Propositions were considered appropriate and applicable in current practice if the median was >=7. Agreement among experts were judged by the statistical measure of the Interpercentile Range

Results

From the first round, 46 recommendations were retained by 49 nurses. 27 propositions were retained after this second round by 32 nurses. The scientific committee added 12 other recommendations because of their importance in the literature and clinical practice.

Conclusions

This study provides consensus-based recommendations on IMI in mental health. Nursing staff need to be educated about the new guidelines from both the theoretical and clinical perspectives

Disclosure

No significant relationships.

Conditional risk of diverticulitis after non-operative management

BACKGROUND

The objective of this study was to describe conditional recurrence-free survival (RFS) of patients after an index episode of diverticulitis managed without surgery, and to estimate the difference in conditional RFS for diverticulitis according to specific risk factors.

METHODS

This was a multicentre retrospective cohort study including all patients managed without surgery for acute sigmoid diverticulitis at two university-affiliated hospitals in Montreal, Quebec, Canada. Conditional RFS for diverticulitis was estimated over 10 years of follow-up. A Cox proportional hazards model was performed at the index episode and again 2 years later.

RESULTS

In total, 991 patients were included for analysis. The 1, 2- and 3-year actuarial diverticulitis RFS rates were 81·1, 71·5 and 67·5 per cent respectively. Compared with the 1-year actuarial RFS rate of 81·1 per cent, the 1-year conditional RFS increased with each additional year survived recurrence-free, reaching 96·0 per cent after surviving the first 4 years recurrence-free. A similar phenomenon was observed for 2-year diverticulitis conditional RFS. Lower age (hazard ratio (HR) 0·98, 95 per cent c.i. 0·98 to 0·99), Charlson Co-morbidity Index score of 2 or above (HR 1·78, 1·32 to 2·39) and immunosuppression (HR 1·85, 1·38 to 2·48) were independently associated with recurrence of diverticulitis from the index episode. At 2 years from the index episode, immunosuppression was no longer associated with diverticulitis recurrence (HR 1·02, 0·50 to 2·09).

CONCLUSION

The conditional RFS of patients with diverticulitis improved with each year that was survived recurrence-free. Although several factors at index presentation may be associated with early recurrence, the conditional probability of recurrence according to many of these risk factors converged with time.

Assessing the readability, quality and accuracy of online health information for patients with low anterior resection syndrome following surgery for rectal cancer

AIM

Management of low anterior resection syndrome (LARS) requires a high degree of patient engagement. This process may be facilitated by online health-related information and education. The aim of this study was to systematically review current online health information on LARS.

METHOD

An online search of Google, Yahoo and Bing was performed using the search terms 'low anterior/anterior resection syndrome' and 'bowel function/movements after rectal cancer surgery'. Websites were assessed for readability (eight standardized tests), suitability (using the Suitability Assessment of Materials instrument), quality (the DISCERN instrument), accuracy and content (using a LARS-specific content checklist). Websites were categorized as academic, governmental, nonprofit or private.

RESULTS

Of 117 unique websites, 25 met the inclusion criteria. The median readability level was 10.4 (9.2-11.7) and 11 (44.0%) websites were highly suitable. Using the DISCERN instrument, seven (28.0%) websites had clear aims, two (8.0%) divulged the sources used and four (16.0%) had high overall quality. Only eight (32.0%) websites defined LARS and ten (40.0%) listed all five major symptoms associated with the LARS score. There was variation in the number of websites that discussed dietary modifications (80.0%), self-help strategies (72.0%), medication (68.0%), pelvic floor rehabilitation (60.0%) and neuromodulation (8.0%). The median accuracy of websites was 93.8% (88.2-96.7%). Governmental websites scored highest for overall suitability (P = 0.0079) and quality (P < 0.001).

CONCLUSIONS

Current online information on LARS is suboptimal. Websites are highly variable, important content is often lacking and material is too complex for patients.

Study protocol evaluating the use of bowel stimulation before loop ileostomy closure to reduce postoperative ileus: a multicenter randomized controlled trial

AIM

Postoperative ileus is the most commonly observed morbidity following ileostomy closure. Studies have demonstrated that the defunctionalized bowel of a loop ileostomy undergoes a series of functional and structural changes, such as atrophy of the intestinal villi and muscular layers, which may contribute to ileus. A single-centre study in Spain demonstrated that preoperative bowel stimulation via the distal limb of the loop ileostomy decreased postoperative ileus, length of stay and time to gastrointestinal function.

METHOD

A multicentre randomized controlled trial involving patients from Canadian institutions was designed to evaluate the effect of preoperative bowel stimulation before ileostomy closure on postoperative ileus. Stimulation will include canalizing the distal limb of the ileostomy loop with an 18Fr Foley catheter and infusing it with a solution of 500 ml of normal saline mixed with 30 g of a thickening agent (Nestle^© Thicken-Up^© ). This will be performed 10 times over the 3 weeks before ileostomy closure in an outpatient clinic setting by a trained Enterostomal Therapy nurse. Surgeons and the treating surgical team will be blinded to their patient's group allocation. Data regarding patient demographics, and operative and postoperative variables, will be collected prospectively. Primary outcome will be postoperative ileus, defined as an intolerance to oral food in the absence of clinical or radiological signs of obstruction, that either requires nasogastric tube insertion or is associated with two of the following on or after post-operative day 3: nausea/vomiting; abdominal distension; and the absence of flatus. Secondary outcomes will include length of stay, time to tolerating a regular diet, time to first passage of flatus or stool and overall morbidity. A cost analysis will be performed to compare the costs of conventional care with conventional care plus preoperative stimulation.

DISCUSSION

This manuscript discusses the potential benefits of preoperative bowel stimulation in improving postoperative outcomes and outlines our protocol for the first multicenter study to evaluate preoperative bowel stimulation before ileostomy closure. The results of this study could have considerable implications for the care of patients undergoing ileostomy closure.

The presence and leachability of antimony in different wastes and waste handling facilities in Norway

The environmental behaviour of antimony (Sb) is gathering attention due to its increasingly extensive use in various products, particularly in plastics. Because of this it may be expected that plastic waste is an emission source for Sb in the environment. This study presents a comprehensive field investigation of Sb concentrations in diverse types of waste from waste handling facilities in Norway. The wastes included waste electrical and electronic equipment (WEEE), glass, vehicle fluff, combustibles, bottom ash, fly ash and digested sludge. The highest solid Sb concentrations were found in WEEE and vehicle plastic (from 1238 to 1715 mg kg(-1)) and vehicle fluff (from 34 to 4565 mg kg(-1)). The type of acid used to digest the diverse solid waste materials was also tested. It was found that HNO3:HCl extraction gave substantially lower, non-quantitative yields compared to HNO3:HF. The highest water-leachable concentration for wastes when mixed with water at a 1 : 10 ratio were observed for plastic (from 0.6 to 2.0 mg kg(-1)) and bottom ash (from 0.4 to 0.8 mg kg(-1)). For all of the considered waste fractions, Sb(v) was the dominant species in the leachates, even though Sb(iii) as Sb2O3 is mainly used in plastics and other products, indicating rapid oxidation in water. This study also presents for the first time a comparison of Sb concentrations in leachate at waste handling facilities using both active grab samples and DGT passive samples. Grab samples target the total suspended Sb, whereas DGT targets the sum of free- and other chemically labile species. The grab sample concentrations (from 0.5 to 50 μg L(-1)) were lower than the predicted no-effect concentration (PNEC) of 113 μg L(-1). The DGT concentrations were substantially lower (from 0.05 to 9.93 μg L(-1)) than the grab samples, indicating much of the Sb is present in a non-available colloidal form. In addition, air samples were taken from the chimney and areas within combustible waste incinerators, as well as from the vent of WEEE sorting facility. The WEEE vent had the highest Sb concentration (from <100 to 2200 ng m(-3)), which were orders of magnitude higher than the air surrounding the combustible shredder (from 25 to 217 ng m(-3)), and the incinerator chimney (from <30 to 100 ng m(-3)). From these results, it seems evident that Sb from waste is not an environmental concern in Norway, and that Sb is mostly readily recovered from plastic and bottom ash.

Lasting alterations of the sodium current by short-term hyperlipidemia as a mechanism for initiation of cardiac remodeling

Clinical and animal studies indicate that increased fatty acid delivery to lean tissues induces cardiac electrical remodeling and alterations of cellular calcium homeostasis. Since this may represent a mechanism initiating cardiac dysfunction during establishment of insulin resistance and diabetes or anaerobic cardiac metabolism (ischemia), we sought to determine if short-term exposure to high plasma concentration of fatty acid in vivo was sufficient to alter the cardiac sodium current ( INa) in dog ventricular myocytes. Our results show that delivery of triglycerides and nonesterified fatty acids by infusion of Intralipid + heparin (IH) for 8 h increased the amplitude of INa by 43% and shifted its activation threshold by −5 mV, closer to the resting membrane potential. Steady-state inactivation (availability) of the channels was reduced by IH with no changes in recovery from inactivation. As a consequence, INa “window” current, a strong determinant of intracellular Na+ and Ca2+ concentrations, was significantly increased. The results indicate that increased circulating fatty acids alter INa gating in manners consistent with an increased cardiac excitability and augmentation of intracellular calcium. Moreover, these changes could still be measured after the dogs were left to recover for 12 h after IH perfusion, suggesting lasting changes in INa. Our results indicate that fatty acids rapidly induce cardiac remodeling and suggest that this process may be involved in the development of cardiac dysfunctions associated to insulin resistance and diabetes.

Abstract P1-09-20: Patient navigation significantly improves vulnerability score after breast cancer. A pilot experience in an underprivileged community

BACKGROUND: We decided to evaluate the effect of patient navigation in an area (Seine-Saint-Denis, SSD) with an estimated population of 1.4 billion, which is among the poorest in France. Median household income is 68% lower than in Paris (+68%), a gap growing with time. In SSD, cancer is the leading cause of premature mortality. Whereas it is widely admitted in France that 25% of patients are faced with financial difficulties after breast cancer, this proportion reaches 40% in SSD.

PATIENTS AND METHODS: Oncologie 93 is a non-profit organization whose aim is to provide supportive care, health education and individualized assistance to patients and families, and to facilitate timely access to quality medical and psychosocial care. Vulnerability was evaluated using a 11-item standardized score (EPICES) previously investigated by French Health Examination Centers. Strictly speaking this score was aimed at measuring precarity, a concept referring to a social condition assumed to face worsening. This score is more strongly related to health status than the administrative classification of poverty (Sass, Sante Publique 2006). Vulnerability was defined by a score &gt;30 and considered as severe when &gt;40. In SSD two thirds of the population are affected by vulnerability. Patients included in the navigation program were scored after cancer diagnosis (E1) and 1 year after the beginning of cancer therapy (E2). Psychosocial comorbidities, demographic data, and treatments received were also recorded.

RESULTS: Over a 1-year period 74 breast cancer patients were included and had E1 and E2 scores, detail of therapy was available for 64 pts. The score significantly improved for the whole population (p = 0.04) but worsened in 23 pts (31%). Among all the variables studied, undergoing surgery was the only one to be significantly correlated with outcome. However, surprisingly, patients who did not undergo surgery had a significantly better evolution of the score than those who did (p = 0.04). E1 score was lower in patients eligible for surgery.

Evolution of median vulnerability score before (E1) and after (E2) breast cancer therapy, first and third quartiles (Q1-Q3) and minimal-maximal values. n =E1Q1-Q3min-maxE2Q1-Q3min-maxwhole population7439.615.8-63.53.17-92.232.87.1-45.81.6-92.1no surgery2447.925.8-57.83.17-75.115.13.6-40.22.7-78.7surgery403714.5-63.93.17-92.233.48-47.31.6-92.9

CONCLUSION: We showed that patient navigation significantly improves vulnerability score during cancer therapy. It emphasizes the importance of evaluating deprivation with standardized tools in cancer patients in order to propose appropriate interventions. The only factor correlated with the evolution of the score is surgery. Patients that were not eligible for surgery had higher E1 score but significantly better evolution during the following year. We hypothesize that deprivation leads to more advanced tumors or is associated with comorbidities contraindicating breast surgery. For unclear reasons, the magnitude of the benefit seems greater in this population. About one third of patients experience worsening of the vulnerability after breast cancer therapy and the underlying mechanisms remain to be determined.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P1-09-20.

Contribution of estrogen receptors alpha and beta to the effects of estradiol in the brain

Clinical and experimental studies show a modulatory role of estrogens in the brain and suggest their beneficial action in mental and neurodegenerative diseases. The estrogen receptors ERalpha and ERbeta are present in the brain and their targeting could bring selectivity and reduced risk of cancer. Implication of ERs in the effect of estradiol on dopamine, opiate and glutamate neurotransmission is reviewed. The ERalpha agonist, PPT, is shown as estradiol to modulate hippocampal NMDA receptors and AMPA receptors in cortex and striatum of ovariectomized rats whereas the ERbeta agonist DPN is inactive. Striatal DPN activity suggests implication of ERbeta in estradiol modulation of D2 receptors and transporters in ovariectomized rats and is supported by the lack of effect of estradiol in ERbeta knockout (ERKObeta) mice. Both ERalpha and ERbeta agonists modulate striatal preproenkephalin (PPE) gene expression in ovariectomized rats. In male mice PPT protects against MPTP toxicity to striatal dopamine; this implicates Akt/GSK3beta signaling and the apoptotic regulators Bcl2 and Bad. This suggests a role for ERalpha in striatal dopamine neuroprotection. ERKOalpha mice are more susceptible to MPTP toxicity and not protected by estradiol; differences in ERKObeta mice are subtler. These results suggest therapeutic potential for the brain of ER specific agonists.

Activated polymorphonuclear cells promote injury and excitability of dorsal root ganglia neurons

Therapies aimed at depleting or blocking the migration of polymorphonuclear leukocytes (PMN or neutrophils) are partially successful in the treatment of neuroinflammatory conditions and in attenuating pain following peripheral nerve injury or subcutaneous inflammation. However, the functional effects of PMN on peripheral sensory neurons such as dorsal root ganglia (DRG) neurons are largely unknown. We hypothesized that PMN are detrimental to neuronal viability in culture and increase neuronal activity and excitability. We demonstrate that isolated peripheral PMN are initially in a relatively resting state but undergo internal oxidative burst and activation by an unknown mechanism within 10 min of co-culture with dissociated DRG cells. Co-culture for 24 h decreases neuronal count at a threshold<0.4:1 PMN:DRG cell ratio and increases the number of injured and apoptotic neurons. Within 3 min of PMN addition, fluorometric calcium imaging reveals intracellular calcium transients in small size (<25 microm diam) and large size (>25 microm diam) neurons, as well as in capsaicin-sensitive neurons. Furthermore, small size isolectin B4-labeled neurons undergo hyperexcitability manifested as decreased current threshold and increased firing frequency. Although co-culture of PMN and DRG cells does not perfectly model neuroinflammatory conditions in vivo, these findings suggest that activated PMN can potentially aggravate neuronal injury and cause functional changes to peripheral sensory neurons. Distinguishing the beneficial from the detrimental effects of PMN on neurons may aid in the development of more effective drug therapies for neurological disorders involving neuroinflammation, including painful neuropathies.

Neutrophils invade lumbar dorsal root ganglia after chronic constriction injury of the sciatic nerve

To test whether neutrophils (PMN) target lumbar dorsal root ganglia (DRG) following axonal injury leading to neuropathic pain, we visualized PMN infiltration in DRG tissue sections and estimated PMN count by flow cytometry following sciatic chronic constriction injury (CCI). Seven days after CCI, results show PMN within DRG where their count increased by three fold ipsilateral to injury compared to contralateral or sham, concomitant with peak neuropathic pain behavior. Superoxide burst in PMN isolated from rats d7 after CCI was elevated by 170% +/-18 compared to naïve and MCP-1 mRNA expression in DRG increased by 8.9+/-2.9 fold, but that of MIP-2, CINC-1, and RANTES did not change. We conclude that CCI causes PMN invasion of the DRG whereby the functional implication of their close proximity to neuronal axon and soma remains unknown.

Right spatial neglect after left hemisphere stroke: qualitative and quantitative study

OBJECTIVES

Comparatively little research has been conducted on right neglect after left brain damage. The authors sought to assess contralateral neglect in subacute left hemisphere stroke patients using a comprehensive test battery validated in a large control group after right hemisphere stroke.

METHODS

Seventy-eight left hemisphere stroke patients were assessed. The test battery included a preliminary assessment of anosognosia and visual extinction, a clinical assessment of gaze orientation and personal neglect, and paper-and-pencil tests of spatial neglect in the peripersonal space. Only nonverbal tests were used.

RESULTS

Drawing and cancellation tasks revealed neglect in 10 to 13% of patients. The combined battery was more sensitive than any single test alone. A total of 43.5% of patients showed some degree of neglect on at least one measure. Anatomic analyses showed that neglect was more common and severe when the posterior association cortex was damaged.

CONCLUSIONS

The frequency of occurrence of right neglect was, as expected, much lower than that reported in a study using the same assessment battery in right brain damage stroke patients. Nevertheless, neglect was found in a substantial proportion of patients at a subacute stage, suggesting that it should be considered in the rehabilitation planning of left brain damage stroke patients.

Oestrogens prevent loss of dopamine transporter (DAT) and vesicular monoamine transporter (VMAT2) in substantia nigra of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine mice

Previous results from our laboratory have shown that 17beta-oestradiol prevents 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) striatal dopamine depletion. 17beta-oestradiol, oestriol and oestrone are the naturally occurring oestogens in humans. Using various dopamine markers, the present study investigated whether oestrone and oestriol such as 17beta-oestradiol have neuroprotective activity in MPTP-treated mice. Male mice were treated with 17beta-oestradiol, oestriol or oestrone for 5 days before and after MPTP administration, and were compared with nonlesioned mice receiving the same treatment. Striatal concentrations of dopamine and its metabolites, 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA), were assayed by high-performance liquid chromatography. Dopamine transporter (DAT) and vesicular monoamine transporter (VMAT2) specific binding were measured by autoradiography. DAT, VMAT2 and tyrosine hydroxylase mRNA levels were measured by in situ hybridisation. MPTP induced a loss of DAT and VMAT2 specific binding in the striatum and substantia nigra, as well as a decrease of VMAT2 mRNA in the substantia nigra. 17beta-oestradiol treatment prevented the loss of these dopaminergic markers, as well as striatal concentrations of dopamine, DOPAC and HVA. Mice receiving oestriol and oestrone showed catecholamine concentrations comparable to MPTP mice. Oestriol treatment had no effect on dopaminergic markers in MPTP mice whereas oestrone prevented striatal DAT loss and the decrease of VMAT2 mRNA in the substantia nigra. In nonlesioned mice, 17beta-oestradiol, oestriol or oestrone had no effect on all the dopaminergic markers investigated. In conclusion, a weak or a lack of effect of oestriol and oestrone was observed compared to 17beta-oestradiol in MPTP mice and none of these steroids had an effect in nonlesioned mice. A DAT and VMAT2 specific binding decrease after MPTP in the striatum and substantia nigra, as well as a decrease of substantia nigra VMAT2 mRNA, was observed and could be prevented by oestradiol.

Characterization of semicarbazide-sensitive amine oxidase in human subcutaneous adipocytes and search for novel functions

Numerous studies have characterized semicarbazide-sensitive amine oxidase activity (SSAO) in rat fat cells but this oxidase is scarcely documented in human adipose tissue. Our aim was to further characterize SSAO in human adipose tissue (activity, mRNA and protein abundance) and to investigate whether SSAO activity can interplay with glucose and lipid metabolism in human adipocytes via the hydrogen peroxide it generates. Polyclonal antibodies directed against bovine lung SSAO allowed the detection of a substantial amount of immunoreactive protein (apparent molecular mass 100 kDa) in human subcutaneous adipocytes from either mammary or abdominal fat depots. A 4-kb mRNA was detected in fat depots using a cDNA probe designed from the placenta SSAO sequence. Almost all the oxidation of benzylamine found in adipose tissue homogenates was due to fat cells and was located in the adipocyte membrane fraction. The oxidation of benzylamine and methylamine were similar and totally inhibited by semicarbazide or hydralazine but resistant to pargyline. Histamine was poorly oxidized. Benzylamine and methylamine dose-dependently stimulated glucose transport in intact adipocytes. This insulin-like effect of amines did not increase in the presence of 0.1 mM vanadate but was inhibited by semicarbazide and antioxidants. Benzylamine and methylamine also exhibited antilipolytic effects, with complete inhibition of lipolysis at 1 mM. These results show that fat cells from non-obese subjects express a membrane-bound SSAO which readily oxidizes exogenous amines, generates hydrogen peroxide and exerts short-term insulin-like actions on glucose and lipid metabolism.

Effect of prolonged treatment with tyramine on glucose tolerance in streptozotocin-induced diabetic rats

The biogenic amine tyramine has been reported to stimulate in vitro glucose transport in adipocytes, cardiomyocytes and skeletal muscle, and to improve in vivo glucose utilization in rats. These effects were dependent on amine oxidation, since they were blocked by inhibitors of monoamine oxidase (MAO) and semicarbazide-sensitive amine oxidase (SSAO). We thus tested in this work whether a prolonged treatment with tyramine could improve glucose tolerance in streptozotocin-induced diabetic rats. First, tyramine content of standard rodent chow was determined by HPLC and daily tyramine intake of control rats was estimated to be around 26 micromol/kg body weight. Then, tyramine was administred during 3 weeks in streptozotocin-induced diabetic rats at 29 micromol/kg by daily i.p. injection alone or together with vanadate 0.02 micromol/kg. In another group of diabetic rats, tyramine was subcutaneously delivered at 116 micromol/kg/day by osmotic minipumps. All tyramine treatments resulted in a decrease of the hyperglycemic responses to an i.p. glucose load. Adipocytes isolated from either untreated or treated diabetic rats were sensitive to the stimulation of glucose uptake by tyramine. However, diabetic animals receiving tyramine for three weeks did not recover from their hyperglycemia, hypoinsulinemia and glucosuria. These results show that the improvement of glucose tolerance induced by prolonged tyramine administration occurs in an insulin-depleted model and probably results from peripheral insulin-like actions of the oxidation of MAO/SSAO substrates, such as the stimulation of glucose uptake into adipocytes.

A novel p21-activated kinase binds the actin and microtubule networks and induces microtubule stabilization

Coordination of the different cytoskeleton networks in the cell is of central importance for morphogenesis, organelle transport, and motility. The Rho family proteins are well characterized for their effects on the actin cytoskeleton, but increasing evidence indicates that they may also control microtubule (MT) dynamics. Here, we demonstrate that a novel Cdc42/Rac effector, X-p21-activated kinase (PAK)5, colocalizes and binds to both the actin and MT networks and that its subcellular localization is regulated during cell cycle progression. In transfected cells, X-PAK5 promotes the formation of stabilized MTs that are associated in bundles and interferes with MTs dynamics, slowing both the elongation and shrinkage rates and inducing long paused periods. X-PAK5 subcellular localization is regulated tightly, since coexpression with active Rac or Cdc42 induces its shuttling to actin-rich structures. Thus, X-PAK5 is a novel MT-associated protein that may communicate between the actin and MT networks during cellular responses to environmental conditions.

Dual action of octopamine on glucose transport into adipocytes: inhibition via beta3-adrenoceptor activation and stimulation via oxidation by amine oxidases

Octopamine, which is closely related to norepinephrine, acts as a neurotransmitter in invertebrates and is a trace amine with undefined properties in vertebrates. The octopaminergic receptors identified in insects are targets of various pesticides but are absent in vertebrates. We have established that octopamine stimulates fat cell lipolysis in mammals via activation of beta3-adrenoceptors (ARs), whereas this amine has been described elsewhere as an alpha2-AR agonist and as a substrate for monoamine oxidase (MAO) or semicarbazide-sensitive amine oxidase (SSAO). Because we have recently reported that amine oxidase substrates promote glucose transport in rat and human adipocytes, the in vitro octopamine effects on lipolysis and glucose uptake were reassessed by using adipocytes from beta3-AR-deficient mice. The lipolytic effect and the counter-regulation of insulin action on glucose transport provoked by 0.1 to 1 mM octopamine or by 1 microM beta3-AR agonists found in control animals disappeared in adipocytes from beta3-AR-deficient mice. This revealed an insulin-like effect of octopamine on glucose uptake, which was dependent on its oxidation by MAO or SSAO, as was the case for tyramine and benzylamine, devoid of beta3-adrenergic agonism. Similarly, octopamine promoted glucose transport in human adipocytes and exhibited a weaker lipolytic stimulation than in rodent adipocytes. These findings indicate that, besides its lipolytic activity, octopamine exerts, at millimolar dose, dual effect on glucose transport in adipocytes: counteracting insulin action via beta3-AR activation and stimulating basal transport via its oxidation by MAO or SSAO.

Semicarbazide-sensitive amine oxidase substrates stimulate glucose transport and inhibit lipolysis in human adipocytes

Semicarbazide-sensitive amine oxidases (SSAO) are widely distributed enzymes scavenging biogenic or exogenous amines and generating hydrogen peroxide. We asked whether human adipose tissue could express SSAO. Since hydrogen peroxide exhibits pharmacological insulin-like effects, we also tested whether its endogenous production by SSAO could mimic several insulin effects on adipocytes, such as stimulation of glucose uptake and inhibition of lipolysis. The benzylamine oxidation by human adipose tissue was inhibited by semicarbazide or hydralazine and resistant to pargyline or selegiline. It was due to an SSAO activity localized in adipocyte membranes. A protein of 100-kDa and a 4-kb mRNA corresponding to SSAO were identified in either mammary or abdominal subcutaneous fat depots. In isolated adipocytes, SSAO oxidized similarly benzylamine and methylamine that dose dependently stimulated glucose transport in a semicarbazide-sensitive manner. Antioxidants also inhibited the benzylamine and methylamine effects. Moreover, the ability of diverse substrates to be oxidized by adipocytes was correlated to their effect on glucose transport. Benzylamine and methylamine exerted antilipolytic effects with a maximum attained at 1 mM. These results show that human adipocytes express a membrane-bound SSAO that not only readily oxidizes exogenous amines and generates H(2)O(2), but that also interplays with glucose and lipid metabolism by exerting insulin-like actions. Based on these results and the fact that variations in plasma levels of the soluble form of SSAO have been previously reported in diabetes, we propose that determination of adipocyte SSAO, feasible on subcutaneous microbiopsies, could bring relevant information in pathologies such as obesity or diabetes.

Buccal hemineglect

OBJECTIVES

To determine whether the peripersonal and intrapersonal buccal space can be affected by a hemispheric stroke and to evaluate the clinical signs resulting from buccal neglect.

METHODS

A prospective study comparing 2 groups of patients with hemiplegia, 1 with a right hemispheric lesion and the other with a left hemispheric lesion. Patients were selected consecutively on the basis of specific criteria at least 1 month after stroke.

RESULTS

Buccal hemineglect was usually concomitant with other hemineglect phenomena resulting from lesions of the right hemisphere (10 of 12 in right lesions and 1 of 12 in left lesions). Clinical signs associated with this condition consisted of impaired swallowing (retention, defective insalivation, presence of food debris in the left hemibuccal space, loss of saliva from the left side of the mouth, and choking); loss of the ability to perceive salty, sweet, or acid tastes; and impaired buccal representation. These problems were usually incorrectly diagnosed initially. Outcome was usually favorable, but functional disorders persisted in some patients for more than 18 months. The underlying attention and representation mechanisms are discussed with reference to experimental lesions of the postarcuate (area 6) cortex in rhesus monkeys. The area around the mouth may be considered to be, as in monkeys, a peripersonal space, ie, probably of little functional importance. The lesion may involve area 6 or its projections to the thalamus or posterior parietal cortex.

CONCLUSIONS

Buccal hemineglect, which is likely to cause social embarrassment, should be considered whenever the oral phase of swallowing is impaired in a context of neglect syndromes. Prophylactic measures and rehabilitation can reduce the impact and complications of the condition (food bolus).

Substrates of semicarbazide-sensitive amine oxidase co-operate with vanadate to stimulate tyrosine phosphorylation of insulin-receptor-substrate proteins, phosphoinositide 3-kinase activity and GLUT4 translocation in adipose cells

It has been shown that the combination of benzylamine or tyramine and low concentrations of vanadate markedly stimulates glucose transport in rat adipocytes by a mechanism that requires semicarbazide-sensitive amine oxidase (SSAO) activity and H(2)O(2) formation. Here we have further analysed the insulin-like effects of the combination of SSAO substrates and vanadate and we have studied the signal-transduction pathway activated in rat adipocytes. We found that several SSAO substrates (benzylamine, tyramine, methylamine, n-decylamine, histamine, tryptamine or beta-phenylethylamine), in combination with low concentrations of vanadate, stimulate glucose transport in isolated rat adipocytes. Furthermore, SSAO substrates together with vanadate stimulated the recruitment of GLUT4 to the cell surface in isolated rat adipocytes. Benzylamine plus vanadate also stimulated glucose transport and GLUT4 translocation in 3T3-L1 adipocytes. Benzylamine or tyramine in combination with vanadate potently stimulated the tyrosine phosphorylation of both insulin receptor substrate (IRS)-1 and IRS-3. In contrast, benzylamine and vanadate caused only a weak stimulation of insulin receptor kinase. Benzylamine or tyramine in combination with vanadate also stimulated phosphoinositide 3-kinase activity; wortmannin abolished the stimulatory effect of benzylamine and vanadate on glucose transport in adipose cells. Furthermore, the administration of benzylamine and vanadate in vivo caused a rapid lowering of plasma glucose levels, which took place in the absence of alterations in plasma insulin. On the basis of these results we propose that SSAO activity regulates glucose transport in adipocytes. SSAO oxidative activity stimulates glucose transport via the translocation of GLUT4 carriers to the cell surface, resulting from a potent tyrosine phosphorylation of IRS-1 and IRS-3 and phosphoinositide 3-kinase activation. Our results also indicate that substrates of SSAO might regulate glucose disposal in vivo.

Hepatitis C viral IRES inhibition by phenazine and phenazine-like molecules

An in vitro assay based on the expression of Fluci reporter gene under the translational control of HCV IRES was used to evaluate and screen compound libraries. A structure-activity relationship study on a phenazine hit was conducted. Our data suggest that an intact phenazine or phenazine-like core with two distal polar substitutions is crucial for potency.

Role of the Y1 receptor in the regulation of neuropeptide Y-mediated feeding: comparison of wild-type, Y1 receptor-deficient, and Y5 receptor-deficient mice

Neuropeptide Y (NPY) increases food intake through the action of hypothalamic NPY receptors. At least six subtypes of NPY, peptide YY (PYY), and pancreatic polypeptide (PP) receptors have been identified in mice. Although the involvement of Y1 and Y5 receptors in feeding regulation has been suggested, the relative importance of each of these NPY receptors and the participation of a novel feeding receptor are still unclear. To address this issue, we generated a Y1 receptor-deficient (Y1-/-) and a Y5 receptor-deficient (Y5-/-) mouse line in which we directly compared the orexigenic effects of NPY and its analogs after intracerebroventricular (icv) administration. The icv NPY-induced food intake was remarkably reduced in Y1-/- mice, but was not significantly altered by inactivation of the Y5 receptor. The Y1 receptor therefore plays a dominant role in NPY-induced feeding. Stimulation of feeding by moderately selective Y5 agonists [PYY-(3-36), human PP, and bovine PP] was reduced in Y5-/- mice, although food intake did not decrease to vehicle control levels. These results indicate that the Y5 receptor functions as one of the feeding receptors. In addition, the finding that Y5-preferring agonists still induce food intake in Y5-/- mice suggests a role for another NPY receptor(s), including the possibility of novel NPY receptors. Surprisingly, despite the limited efficacy of PYY-(3-36) and PPs at the Y1 receptor, food consumption induced by these agonists was significantly diminished in Y1-/- mice compared with that in wild-type controls. These observations suggest that the feeding stimulation induced by NPY and its analogs may be directly or indirectly modulated by the action of the Y1 receptor. We conclude that multiple NPY receptors, possibly including the novel feeding receptor, are involved in the feeding response evoked by NPY and its analogs. Among them, the Y1 receptor plays a key role in NPY-induced feeding in mice.

Regulation of Xenopus p21-activated kinase (X-PAK2) by Cdc42 and maturation-promoting factor controls Xenopus oocyte maturation

Signal transduction cascades involved in regulation of the cell cycle machinery are poorly understood. In the Xenopus oocyte model, meiotic maturation is triggered by MPF, a complex of p34(cdc2)-cyclin B, which is activated in response to a progesterone signal by largely unknown mechanisms. We have previously shown that the p21-activated kinase (PAK) family negatively regulates the MPF amplification loop. In this study, we identify the endogenous PAK2 as a key enzyme in this regulation and describe the pathways by which PAK2 is regulated. We show that the small GTPase Cdc42 is required for maintenance of active endogenous X-PAK2 in resting stage VI oocytes, whereas Rac1 is not involved in this regulation. During the process of maturation, X-PAK2 phosphorylation results in its inactivation and allows maturation to proceed to completion. Activation of mitogen-activated protein kinase and cyclin B-p34(cdc2) is coincident with X-PAK2 inactivation, and purified active MPF inhibits X-PAK2, demonstrating the existence of a new positive feedback loop. Our results confirm and extend the importance of p21-activated kinases in the control of the G(2)/M transition. We hypothesize that the X-PAK2/Cdc42 pathway could link p34(cdc2) activity to the major cytoskeleton rearrangements leading to spindle migration and anchorage to the animal pole cortex.

Effects of octopamine on lipolysis, glucose transport and amine oxidation in mammalian fat cells

Octopamine is known to exert adrenergic effects in mammals although specific octopamine receptors have been cloned only in invertebrates. It has been shown that octopamine can stimulate alpha(2)-adrenoceptors (ARs) in Chinese hamster ovary cells transfected with human alpha(2)-ARs. More recently, we reported that octopamine stimulates lipolysis through beta(3)-rather than beta(1)-or beta(2)-AR activation in white adipocytes from different mammalian species. The present study was thus undertaken to further characterize the adrenergic properties of octopamine. For this purpose, several biological processes known to be regulated by adrenergic stimulation were studied in response to octopamine, noradrenaline, adrenaline and tyramine in white adipocytes from different mammals. First, octopamine was fully lipolytic in garden dormouse and Siberian hamster while tyramine was ineffective. Although being around one hundred-fold less potent that noradrenaline, octopamine was slightly more potent in these hibernators known for their high sensitivity to beta(3)-AR agonists than in rat and chiefly more active than in human adipocytes known for their limited responses to beta(3)-AR agonists. Second, octopamine reduced insulin-dependent glucose transport in rat fat cells, a response also observed with noradrenaline and selective beta(3)-AR agonists but not with beta(1)-or beta(2)-agonists. Third, human adipocytes, which endogenously express a high level of alpha(2)-ARs, exhibited a clear alpha(2)-adrenergic antilipolytic response to adrenaline but not to octopamine. Moreover, octopamine exhibited only a very weak affinity for the alpha(2A)-ARs labeled by [3H]RX821002 in human adipocyte membranes. In Syrian hamster adipocytes, which also possess alpha(2)-ARs, octopamine induced only a weak antilipolysis. Finally, octopamine was a substrate of fat cell amine oxidases, with an apparent affinity similar to that of noradrenaline. All these results demonstrate that octopamine, tyramine noradrenaline and adrenaline can be degraded by adipocyte amine oxidases. However these biogenic amines interact differently with adipocyte adrenoceptors: tyramine is inactive, adrenaline and noradrenaline activate both beta- and alpha(2)-ARs while octopamine activates only beta(3)-ARs and is devoid of alpha(2)-adrenergic agonism. Thus, octopamine could be considered as an endogenous selective beta(3)-AR agonist.

Control of G2/M transition in Xenopus by a member of the p21-activated kinase (PAK) family: a link between protein kinase A and PAK signaling pathways?

X-PAKs are involved in negative control of the process of oocyte maturation in Xenopus (). In the present study, we define more precisely the events targetted by the kinase in the inhibition of the G2/M transition. We show that microinjection of recombinant X-PAK1-Cter active kinase into progesterone-treated oocytes prevents c-Mos accumulation and activation of both MAPK and maturation-promoting factor (MPF). In conditions permissive for MAPK activation, MPF activation still fails. We demonstrate that a constitutive truncated version of X-PAK1 (X-PAK1-Cter) does not prevent the association of cyclin B with p34(cdc2) but rather prevents the activation of the inactive complexes present in the oocyte. Proteins participating in the MPF amplification loop, including the Cdc25-activating Polo-like kinase are all blocked. Indeed, using active MPF, the amplification loop is not turned on in the presence of X-PAK1. Our results indicate that X-PAK and protein kinase A targets in the control of oocyte maturation are similar and furthermore that this negative regulation is not restricted to meiosis, because we demonstrate that G2/M progression is also prevented in Xenopus cycling extracts in the presence of active X-PAK1.

A novel role for glycogen synthase kinase-3 in Xenopus development: maintenance of oocyte cell cycle arrest by a beta-catenin-independent mechanism

We have examined the expression of glycogen synthase kinase-3beta in oocytes and early embryos of Xenopus and found that the protein is developmentally regulated. In resting oocytes, GSK-3beta is active and it is inactivated on maturation in response to progesterone. GSK-3beta inactivation is necessary and rate limiting for the cell cycle response to this hormone and the subsequent accumulation of beta-catenin. Overexpression of a dominant negative form of the kinase accelerates maturation, as does inactivation by expression of Xenopus Dishevelled or microinjection of an inactivating antibody. Cell cycle inhibition by GSK-3beta is not mediated by the level of beta-catenin or by a direct effect on either the MAP kinase pathway or translation of mos and cyclin B1. These data indicate a novel role for GSK-3beta in Xenopus development: in addition to controlling specification of the dorsoventral axis in embryos, it mediates cell cycle arrest in oocytes.

In vitro embryo production in the cow: an effective alternative to the conventional embryo production approach

Development of new technology related to in vitro embryo production has allowed for the commercial use of this method of reproduction. In the present work, we evaluate the efficiency of this technology compared with conventional embryo production based on results obtained with a standard procedure, including the sexing of embryos. The donor animals were mature nonlactating dairy cows (n = 92) kept under a constant environment and feeding program in an ET center. Ultrasound guided transvaginal ovum pick-up following 48 h pre-treatment with FSH has been used for the IVF-IVC protocol. A total of 437 oocyte recovery sessions performed on 92 cows yielded 4145 oocytes, which were used in an IVF-IVC protocol. Using the conventional approach, 156 embryo collections on 49 cows yielded 1652 ova and embryos. All Quality 1 and 2 embryos were sexed by a PCR procedure, and embryos of the desired sex were transferred to synchronized recipients located at the center. The results obtained in the IVF protocol showed that 4 oocyte collections per cow performed within 60 d, yielded 38 oocytes, which resulted in 18.8 viable embryos, of which 7.05 were female. After transfer of the female embryos, an average of 3.8 recipients were pregnant at 60 d. One embryo collection under the conventional approach yielded an average of 1.2 female pregnancies, which was confirmed during the same 60-d time period. These results indicate that IVF procedures can effectively replace conventional embryo production methods when a predetermined number of pregnancies of known sex are needed within a short period of time.

Characterization of human immunodeficiency virus type-1 (HIV-1) particles that express protease-reverse transcriptase fusion proteins

We have selectively mutagenized specific residues at the junction between the protease (PR) and reverse transcriptase (RT) genes of human immunodeficiency virus type 1 (HIV-1) to study the effects of PR-RT fusion proteins in the context of a full-length, infectious proviral construct. Mutant viruses derived from COS-7 cells transfected with this construct were analyzed in regard to each of viral replication, maturation, and infectivity. Immunoblot analysis revealed that the mutation prevented cleavage between the PR and RT proteins and that both existed as a PR-RT fusion protein in each of cellular and viral lysates. Interestingly, intracellular PR that existed within the PR-RT fusion protein remained functionally active, whereby HIV-1 precursor proteins were processed efficiently. Furthermore, the RT component of the fusion protein also retained its enzymatic activity as shown in RT assays. Electron microscopy revealed that the mutant viruses containing the PR-RT fusion protein possessed wild-type morphology. These viruses also displayed wild-type sensitivities to inhibitors of each of the HIV-1 PR and RT activities. However, viruses containing the PR-RT fusion protein were 20 times less infectious than wild-type viruses. This defect was further pronounced when mutated Gag-Pol proteins were overexpressed as a consequence of an additional mutation that interfered with frameshifting. Thus, unlike cleavage site mutations at the N terminus of PR, a cleavage site mutation between PR and RT did not affect the enzymatic activities of either PR or RT and viruses containing PR-RT fusion proteins were viable.

Inactivation of protein kinase A is not required for c-mos translation during meiotic maturation of Xenopus oocytes

It has been shown previously that protein kinase A (PKA) maintains Xenopus oocytes arrested at G2, at least in part by preventing c-mos translation, but how PKA controls c-mos translation is not known. Using microinjection of recombinant c-mos, which still activates MAP kinase in the presence of active PKA, we have found that PKA does not exert any effect on translation of endogenous c-mos if MAP kinase is first activated. Even though they accumulate c-mos and contain MAP kinase activity as high as control oocytes, oocytes do not exit G2 in the presence of active PKA. These results are discussed in connection with recent findings on regulation of c-raf activity.