Walking Responses of Tribolium castaneum (Coleoptera: Tenebrionidae) to Its Aggregation Pheromone and Odors of Wheat Infestations.

The red flour beetle, Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae), is a worldwide pest of stored grains. Using "Y"-tube olfactometry we studied the response of T. castaneum to odors from simulated wheat infestations containing conspecifics, and infestations containing the lesser grain borer, Rhyzopertha dominica (F.) (Coleoptera: Bostrichidae), and the granary weevil Sitophilus granarius (L.) (Coleoptera: Curculionidae). Tribolium castaneum larvae were significantly attracted to odors from all three test species. Tribolium castaneum adults were attracted to grains infested by R. dominica and flour infested by T. castaneum but repelled from grains infested by S. granarius. Further behavioral analysis with pheromones showed that T. castaneum were significantly attracted to their aggregation pheromone, dimethyldecanal (DMD), but not to the R. dominica aggregation pheromone, a mixture of dominicalure 1 and 2. Female T. castaneum adults were attracted to ∼50-fold less DMD than larvae and 100-fold less than male adults, suggesting they are more sensitive to DMD. This study improves our understanding of T. castaneum behaviors to infested grain volatile compounds and pheromones, and may help develop new control methods for grain pest species.

"I think we've got too many tests!": Prenatal providers' reflections on ethical and clinical challenges in the practice integration of cell-free DNA screening.

BACKGROUND: The recent introduction of cell-free DNA-based non-invasive prenatal screening (cfDNA screening) into clinical practice was expected to revolutionize prenatal testing. cfDNA screening for fetal aneuploidy has demonstrated higher test sensitivity and specificity for some conditions than conventional serum screening and can be conducted early in the pregnancy. However, it is not clear whether and how clinical practices are assimilating this new type of testing into their informed consent and counselling processes. Since the introduction of cfDNA screening into practice in 2011, the uptake and scope have increased dramatically. Prenatal care providers are under pressure to stay up to date with rapidly changing cfDNA screening panels, manage increasing patient demands, and keep up with changing test costs, all while attempting to use the technology responsibly and ethically. While clinical literature on cfDNA screening has shown benefits for specific patient populations, it has also identified significant misunderstandings among providers and patients alike about the power of the technology. The unique features of cfDNA screening, in comparison to established prenatal testing technologies, have implications for informed decision-making and genetic counselling that must be addressed to ensure ethical practice. OBJECTIVES: This study explored the experiences of prenatal care providers at the forefront of non-invasive genetic screening in the United States to understand how this testing changes the practice of prenatal medicine. We aimed to learn how the experience of providing and offering this testing differs from established prenatal testing methodologies. These differences may necessitate changes to patient education and consent procedures to maintain ethical practice. METHODS: We used the online American Congress of Obstetricians and Gynecologists Physician Directory to identify a systematic sample of five prenatal care providers in each U.S. state and the District of Columbia. Beginning with the lowest zip code in each state, we took every fifth name from the directory, excluding providers who were retired, did not currently practice in the state in which they were listed, or were not involved in a prenatal specialty. After repeating this step twice and sending a total of 461 invitations, 37 providers expressed interest in participating, and we completed telephone interviews with 21 providers (4.6%). We developed a semi-structured interview guide including questions about providers' use of and attitudes toward cfDNA screening. A single interviewer conducted and audio-recorded all interviews by telephone, and the interviews lasted approximately 30 minutes each. We collaboratively developed a codebook through an iterative process of transcript review and code application, and a primary coder coded all transcripts. RESULTS: Prenatal care providers have varying perspectives on the advantages of cfDNA screening and express a range of concerns regarding the implementation of cfDNA screening in practice. While providers agreed on several advantages of cfDNA, including increased accuracy, earlier return of results, and decreased risk of complications, many expressed concern that there is not enough time to adequately counsel and educate patients on their prenatal screening and testing options. Providers also agreed that demand for cfDNA screening has increased and expressed a desire for more information from professional societies, labs, and publications. Providers disagreed about the healthcare implications and future of cfDNA screening. Some providers anticipated that cfDNA screening would decrease healthcare costs when implemented widely and expressed optimism for expanded cfDNA screening panels. Others were concerned that cfDNA screening would increase costs over time and questioned whether the expansion to include microdeletions could be done ethically. CONCLUSIONS: The perspectives and experiences of the providers in this study allow insight into the clinical benefit, burden on prenatal practice, and potential future of cfDNA screening in clinical practice. Given the likelihood that the scope and uptake of cfDNA screening will continue to increase, it is essential to consider how these changes will affect frontline prenatal care providers and, in turn, patients. Providers' requests for additional guidance and data as well as their concerns with the lack of time available to explain screening and testing options indicate significant potential issues with patient care. It is important to ensure that the clinical integration of cfDNA screening is managed responsibly and ethically before it expands further, exacerbating pre-existing issues. As prenatal screening evolves, so should informed consent and the resources available to women making decisions. The field must take steps to maximize the advantages of cfDNA screening and responsibly manage its ethical issues.

CONTEXTE: L'introduction récente du dépistage prénatal non invasif (dépistage cfDNA) exempt de cellules à base d'ADN dans la pratique clinique devait révolutionner le dépistage prénatal. Le dépistage cfDNA de l'aneuploïdie fœtale a démontré une meilleure sensibilité et spécificité que le dépistage sérique classique et peut être effectué au début de la grossesse. Cependant, on ne sait pas si et comment les pratiques cliniques assimilent ce nouveau type de test dans leurs processus de consentement et de conseil éclairés. Depuis l'introduction du dépistage cfDNA dans la pratique en 2011, l'absorption et la portée ont augmenté de façon spectaculaire. Les professionnels sont sous pression pour rester à jour avec l'évolution rapide des échantillons cfDNA, gérer la demande croissante des patients, et suivre l'évolution des coûts de test, tout en essayant d'utiliser la technologie de manière responsable et éthique. Bien que la littérature clinique sur le dépistage cfDNA a montré des avantages pour les populations de patients spécifiques, elle a également identifié des malentendus importants entre les professionnels et les patients sur le pouvoir de la technologie. Les caractéristiques uniques du dépistage cfDNA, par rapport aux technologies de dépistage prénatal établies, ont des implications pour la prise de décisions éclairées et le conseil génétique qui rentrent en compte pour assurer une pratique éthique. OBJECTIFS: Cette étude a exploré les expériences des professionnels à la pointe du dépistage génétique non invasif aux États-Unis pour comprendre comment ce test modifie la pratique de la médecine prénatale. Nous avons cherché à savoir comment l'expérience de fournir et d'offrir ce test diffère des méthodes plus anciennes de dépistage prénatal. Ces différences peuvent nécessiter des changements dans l'éducation du patient et les procédures de consentement pour maintenir une pratique éthique. MÉTHODES: Nous avons utilisé l'annuaire en ligne du Congrès américain des médecins obstétriciens et gynécologues pour identifier un échantillon systématique de cinq fournisseurs de soins prénatals dans chaque État américain et le District de Columbia. En commençant par le code postal le plus bas dans chaque état, nous avons pris tous les cinquièmes noms de l'annuaire, à l'exclusion des prestataires qui étaient à la retraite, ne pratiquait pas actuellement dans l'état dans lequel ils ont été énumérés, ou ne sont pas impliqués dans une spécialité prénatale. Après avoir répété cette étape deux fois et l'envoi d'un total de 461 invitations, 37 professionnels ont exprimé leur intérêt à participer, et nous avons réalisé des entrevues téléphoniques avec 21 fournisseurs (4,6 %). Nous avons développé un entretien semi-dirigé comprenant des questions sur l'utilisation de fournisseurs de dépistage et les attitudes envers le cfDNA. Un seul intervieweur a mené et enregistré toutes les interviews par téléphone, les entretiens ont duré environ 30 minutes chacun. Nous avons développé en collaboration un dictionnaire par un processus itératif d'examen de la transcription et de l'application du code, et un codeur primaire a codé toutes les transcriptions. RÉSULTATS: Les professionnels de soins prénataux ont des points de vue variés sur les avantages du dépistage cfDNA et expriment une gamme de préoccupations concernant la mise en œuvre du dépistage cfDNA dans la pratique. S'ils ont convenu de plusieurs avantages de cfDNA, y compris une précision accrue, un retour plus rapide des résultats et une diminution de risque de complications, une préoccupation exprimée est qu'il n'y a pas suffisamment pour conseiller et éduquer les patients sur les options de dépistage et de dépistage prénatal. Les professionnels ont également convenu que la demande pour le dépistage cfDNA a augmenté et ont souhaité plus d'informations émanant des sociétés professionnelles, des laboratoires et des publications. Les fournisseurs étaient en désaccord au sujet des implications sur la santé et sur l'avenir du dépistage cfDNA. Certains fournisseurs prévoyaient que le dépistage cfDNA diminuerait les coûts des soins de santé lorsqu'ils seront appliqués largement et a exprimé son optimisme pour l'élargissement des échantillons de dépistage cfDNA. D'autres craignaient que le dépistage cfDNA augmenterait les coûts au fil du temps et se sont demandé si la possibilité d'y inclure les microdélétions pourrait être fait sur le plan éthique. CONCLUSIONS: Les perspectives et les expériences des fournisseurs dans cette étude permettent d'avoir un aperçu de l'avantage clinique, de la charge sur la pratique prénatale, et du futur potentiel du dépistage cfDNA dans la pratique clinique. Compte tenu de la probabilité que la portée et l'acceptation du dépistage cfDNA vont continuer à augmenter, il est essentiel d'examiner comment ces changements auront une incidence sur les fournisseurs de soins prénataux de première ligne et sur les patients. Les demandes de professionnels pour obtenir des conseils et des données supplémentaires ainsi que leurs préoccupations sur le manque de temps disponible pour expliquer aux patients les options de dépistage et de tests indiquent des problèmes potentiellement lourds. Il est important de veiller à ce que l'intégration clinique du dépistage cfDNA soit gérée de façon responsable et éthique avant qu'il ne se développe davantage, aggravant les problèmes préexistants. Comme le dépistage prénatal évolue, de même devrait évoluer le consentement éclairé et les ressources disponibles pour que les femmes puissent prendre leur décision. La discipline doit prendre des mesures pour maximiser les avantages du dépistage cfDNA et gérer de façon responsable les questions éthiques qui s'y rapportent.

Mitochondrial protection by the JNK inhibitor leflunomide rescues mice from acetaminophen-induced liver injury.

UNLABELLED: Acetaminophen (APAP) is a widely used analgesic and antipyretic drug that is safe at therapeutic doses but which can precipitate liver injury at high doses. We have previously found that the antirheumatic drug leflunomide is a potent inhibitor of APAP toxicity in cultured human hepatocytes, protecting them from mitochondria-mediated cell death by inhibiting the mitochondrial permeability transition. The purpose of this study was to explore whether leflunomide protects against APAP hepatotoxicity in vivo and to define the molecular pathways of cytoprotection. Male C57BL/6 mice were treated with a hepatotoxic dose of APAP (750 mg/kg, ip) followed by a single injection of leflunomide (30 mg/kg, ip). Leflunomide (4 hours after APAP dose) afforded significant protection from liver necrosis as assessed by serum ALT activity and histopathology after 8 and 24 hours. The mechanism of protection by leflunomide was not through inhibition of cytochrome P450 (CYP)-catalyzed APAP bioactivation or an apparent suppression of the innate immune system. Instead, leflunomide inhibited APAP-induced activation (phosphorylation) of c-jun NH2-terminal protein kinase (JNK), thus preventing downstream Bcl-2 and Bcl-XL inactivation and protecting from mitochondrial permeabilization and cytochrome c release. Furthermore, leflunomide inhibited the APAP-mediated increased expression of inducible nitric oxide synthase and prevented the formation of peroxynitrite, as judged from the absence of hepatic nitrotyrosine adducts. Even when given 8 hours after APAP dose, leflunomide still protected from massive liver necrosis. CONCLUSION: Leflunomide afforded protection against APAP-induced hepatotoxicity in mice through inhibition of JNK-mediated activation of mitochondrial permeabilization.

Pharmacokinetic study of intraperitoneally administered troglitazone in mice using ultra-performance liquid chromatography/tandem mass spectrometry.

A rapid and sensitive ultra-performance liquid chromatography/tandem mass spectrometry (UPLC/MS/MS) method was developed and validated for the determination of troglitazone in mouse plasma. Troglitazone and its internal standard (IS), rosiglitazone, were separated on an ACQUITY UPLC BEH C(18) column (1.7 microm particle size, 50 x 2.1 mm i.d.) by gradient elution with water and methanol at a flow rate of 0.5 mL/min. The cycle time of each analysis was 2.5 min. Rosiglitazone and troglitazone eluted at 1.13 and 1.57 min, respectively, and were chromatographically resolved from the ion suppression and enhancement zones due to the biological matrix effect. Quantitation of the analytes was performed in electrospray negative ionization mode (ESI -ve) using multiple reaction monitoring (MRM) experiments. The weighted (1/x) calibration curve was quadratic over the plasma concentration range 1-2500 ng/mL with a correlation coefficient (r(2)) of 0.9966. The limit of quantitation (LOQ) of troglitazone in mouse plasma was lower than 1 ng/mL. The inter- and intra-day variations of the assay were lower than 12.1%; the overall accuracy ranged from 86.4-110.2% and recovery from spiked plasma was more than 60%. The developed method was successfully applied to determine troglitazone in mouse plasma after intraperitoneal administration.

Troglitazone-induced hepatic necrosis in an animal model of silent genetic mitochondrial abnormalities.

Troglitazone, a first-generation thiazolidinedione antidiabetic drug, was withdrawn from the market due to an unacceptable risk of idiosyncratic hepatotoxicity. Troglitazone does not cause hepatotoxicity in normal healthy rodents, but it produces mitochondrial injury in vitro at high concentrations. The aim of this study was to explore whether genetic mitochondrial abnormalities might sensitize mice to hepatic adverse effects of troglitazone. We used heterozygous superoxide dismutase 2 (Sod2(+/-)) mice as a model of clinically silent mitochondrial stress. Troglitazone was daily administered for 4 weeks (0, 10 or 30 mg/kg/day, ip). We found that troglitazone caused overt liver injury in the high-dose group, manifested by increased serum alanine aminotransferase activity (> twofold) and midzonal areas of hepatic necrosis, in Sod2(+/-) but not in wild-type mice. No signs of hepatotoxicity were apparent at 2 weeks of treatment. Hepatic mitochondria isolated from troglitazone-treated mice exhibited decreased activities of aconitase (by 45%) and complex I (by 46%) and increased (by 58%) protein carbonyls, indicative of enhanced mitochondrial oxidant stress. This was paralleled by compensatory increases in mitochondrial glutathione levels. Finally, in hepatocytes isolated from untreated Sod2(+/-), but not wild-type mice, troglitazone caused a concentration-dependent increase in superoxide anion levels as demonstrated with a selective mitochondria-targeting fluorescent probe. In conclusion, prolonged administration of troglitazone can superimpose oxidant stress, potentiate mitochondrial damage, and induce delayed hepatic necrosis in mice with genetically compromised mitochondrial function. These data are consistent with our hypothesis that inherited or acquired mitochondrial abnormalities may be one of the contributing determinants of susceptibility to troglitazone-induced idiosyncratic liver injury.

Nimesulide-induced hepatic mitochondrial injury in heterozygous Sod2(+/-) mice.

Nimesulide, a preferential COX-2 inhibitor, has been associated with rare idiosyncratic hepatotoxicity. The underlying mechanisms of liver injury are unknown, but experimental evidence has identified oxidative stress as a potential hazard and mitochondria as a target. The aim of this study was to explore whether genetic mitochondrial abnormalities, resulting in impaired mitochondrial function and mildly increased oxidative stress, might sensitize mice to the hepatic adverse effects of nimesulide. We used heterozygous superoxide dismutase 2 (Sod2(+/-)) mice as a model, as these mice develop clinically silent mitochondrial stress but otherwise appear normal. Nimesulide was administered for 4 weeks (10 mg/kg, ip, bid), at a dose equivalent to human therapeutic dosage. We found that the drug potentiated hepatic mitochondrial oxidative injury (decreased aconitase activity, increased protein carbonyls) in Sod2(+/-), but not wild-type, mice. Furthermore, the nimesulide-treated mutant mice exhibited increased hepatic cytosolic levels of cytochrome c and caspase-3 activity, as well as increased numbers of apoptotic hepatocytes. Finally, nimesulide in vitro caused a concentration-dependent net increase in superoxide anion in mitochondria from Sod2(+/-), but not Sod2(+/+) mice. In conclusion, repeated administration of nimesulide can superimpose an oxidant stress, potentiate mitochondrial damage, and activate proapoptotic factors in mice with genetically compromised mitochondrial function.

Mitochondrial permeability transition as a source of superoxide anion induced by the nitroaromatic drug nimesulide in vitro.

Nimesulide, a widely used nonsteroidal anti-inflammatory drug containing a nitroaromatic moiety, has been associated with rare but serious hepatic adverse effects. The mechanisms underlying this idiosyncratic hepatotoxicity are unknown; however, both mitochondrial injury and oxidative stress have been implicated in contributing to liver injury in susceptible patients. The aim of this study was, first, to explore whether membrane permeability transition (MPT) could contribute to nimesulide's mitochondrial toxicity and, second, whether metabolism-derived reactive oxygen species (ROS) were responsible for MPT. We found that isolated mouse liver mitochondria readily underwent Ca2+-dependent, cyclosporin A-sensitive MPT upon exposure to nimesulide (at >or=3 microM). Net increases in mitochondrial superoxide anion levels, determined with the fluorescent probe dihydroethidium, were induced by nimesulide only in the presence of Ca2+ and were cyclosporin A-sensitive, indicating that superoxide production was a consequence, rather than the cause, of MPT. In addition, nimesulide caused a rapid dissipation of the inner mitochondrial transmembrane potential (at >or=3 microM), followed by a concentration-dependent decrease in ATP biosynthesis. Because nimesulide, unlike the related nitroaromatic drug nilutamide, did not produce any detectable ROS during incubation with mouse hepatic microsomes, we conclude that mitochondrial uncoupling causes MPT and that ROS production is a secondary effect.

Intratracheal instillation of zinc-cadmium sulfide (ZnCdS) in Fischer 344 rats.

The purpose of this study was to assess the bioavailability and pulmonary toxicity of ZnCdS in rats. Groups of 30 male Fischer 344 rats each were anesthetized and dosed via intratracheal instillation with 5 mg of either ZnCdS, quartz (positive control), or titanium dioxide (TiO(2), negative control) suspended in 0.5 ml saline. A vehicle control group received 0.5 ml saline. Ten animals from each test group were sacrificed at 1 day, 1 wk, and 14 wk after dosing for bronchoalveolar lavage fluid (BALF) analysis and histopathology. The BALF was analyzed for alkaline phosphatase, acid phosphatase, lactate dehydrogenase (LDH), beta-glucuronidase (beta-glu), total protein, and cell counts. Two separate groups of 24 rats each were dosed as already described with either ZnCdS or saline. Eight rats from each group were sacrificed at 1 day, 1 wk, and 14 wk after dosing for determination of cadmium (Cd) and zinc (Zn) concentrations in the lung, liver, kidney, and blood. Results indicate that at 1 day after dosing, all enzyme activities (except acid phosphatase) and cell counts in BALF from the quartz and ZnCdS groups were significantly higher than in the TiO(2) and saline groups. At 7 days after dosing, high enzyme activity persisted in the quartz group, while the ZnCdS group showed only LDH and total protein levels significantly higher than the saline group. At 14 wk after dosing, LDH, total protein, beta-glu, and cell counts in the quartz group were significantly higher than all other groups. Histologic examination revealed interstitial inflammation and accumulation of foreign material in the lungs and mediastinal lymph nodes of quartz-, TiO(2)-, and ZnCdS-treated rats. Metal analyses in tissues showed profuse Cd and Zn concentrations in the lung 1 day after dosing, followed by a successive decline at 7 days and 14 wk after dosing. A very small, but statistically significant, amount of Cd and Zn was found in the kidneys at 14 wk after dosing. In conclusion, ZnCdS appears to cause temporary lung inflammation, is cleared slowly, and is poorly bioavailable.

IL-18, a novel immunoregulatory cytokine, is up-regulated in Crohn's disease: expression and localization in intestinal mucosal cells.

IL-18, a novel immunoregulatory cytokine with potent IFN-gamma-inducing activities, may play an important role in Th1-mediated chronic inflammatory disorders. The aim of the present study was to characterize the expression and localization of IL-18 in colonic specimens and isolated mucosal cell populations from patients with Crohn's disease (CD), a prototypic Th1-mediated disorder. Using a semiquantitative RT-PCR protocol, IL-18 mRNA transcripts were found to be increased in freshly isolated intestinal epithelial cells (IEC) and lamina propria mononuclear cells (LPMC) from CD compared with ulcerative colitis (UC) and noninflamed control (cont) patients, and were more abundant in IEC compared with LPMC. Immunohistochemical analysis of surgically resected colonic tissues localized IL-18 to both LPMC (specifically, macrophages and dendritic cells) as well as IEC. Staining was more intense in CD compared with UC and cont, and in involved (inv) vs noninvolved (n inv) areas. Western blot analysis revealed that an 18. 3-kDa band, consistent with both recombinant and mature human IL-18 protein, was found predominantly in CD vs UC intestinal mucosal biopsies; a second band of 24 kDa, consistent with the inactive IL-18 precursor, was detected in n inv areas from both CD and UC biopsies and was the sole form found in noninflamed cont. To our knowledge, this report is the first describing increased expression of IL-18 in a human Th1-mediated chronic inflammatory disease. In addition, our studies further support the concept that IEC and dendritic cells may possess important immunoregulatory functions in both normal, as well as pathological, mucosal immunity.

A controlled trial of dothiepin and placebo in treating benzodiazepine withdrawal symptoms.

BACKGROUND: The possibility that treatment with tricyclic antidepressants, in the form of dothiepin, might attenuate benzodiazepine withdrawal symptoms was investigated in a double-blind trial. METHOD: Eighty-seven non-depressed psychiatric out-patients with putative normal dose benzodiazepine dependence had their benzodiazepines reduced in stepwise amounts of 20% of the original dose for eight weeks. The patients were randomised to receive dothiepin (with dosage increasing to 150 mg/day) or placebo as an aid to withdrawal before benzodiazepine reduction and these drugs were taken for four further weeks before being stopped. RESULTS: Fewer patients entered and completed the study than expected and a Type II error was possible in the results. Although there was some evidence of withdrawal symptoms being less marked in those patients allocated to dothiepin this was independent of any antidepressant effect as depression scores were lower in the placebo group in the early phase of withdrawal (P < 0.01). Of those completing the study, greater satisfaction (P = 0.03) was recorded by those who had received dothiepin; no other differences reached statistical significance. CONCLUSIONS: Dothiepin (and by implication other tricyclic antidepressants) might have some value in reducing benzodiazepine withdrawal symptoms but does not aid drug withdrawal.

Hand and wrist function after external fixation of unstable distal radial fractures.

Twenty-eight patients with 31 fractures of the distal radius were treated by closed external fixation. The complication rate for this series was 50%. Anatomic results were acceptable but hand function at final review was disappointing, particularly in the measurement of grip strength and the patient's ability to perform the activities of daily living. There was a highly significant correlation between complications and poor functional outcome. Although external fixation can achieve restoration of normal anatomy, functional outcome may be poor because of the severity of the associated soft tissue injury.