Genome-wide analysis of translation reveals a critical role for deleted in azoospermia-like (Dazl) at the oocyte-to-zygote transition.

Oocyte maturation, fertilization, and early embryonic development occur in the absence of gene transcription. Therefore, it is critical to understand at a global level the post-transcriptional events that are driving these transitions. Here we used a systems approach by combining polysome mRNA profiling and bioinformatics to identify RNA-binding motifs in mRNAs that either enter or exit the polysome pool during mouse oocyte maturation. Association of mRNA with the polysomes correlates with active translation. Using this strategy, we identified highly specific patterns of mRNA recruitment to the polysomes that are synchronized with the cell cycle. A large number of the mRNAs recovered with translating ribosomes contain motifs for the RNA-binding proteins DAZL (deleted in azoospermia-like) and CPEB (cytoplasmic polyadenylation element-binding protein). Although a Dazl role in early germ cell development is well established, no function has been described during oocyte-to-embryo transition. We demonstrate that CPEB1 regulates Dazl post-transcriptionally, and that DAZL is essential for meiotic maturation and embryonic cleavage. In the absence of DAZL synthesis, the meiotic spindle fails to form due to disorganization of meiotic microtubules. Therefore, Cpeb1 and Dazl function in a progressive, self-reinforcing pathway to promote oocyte maturation and early embryonic development.

PDE4D and PDE4B function in distinct subcellular compartments in mouse embryonic fibroblasts.

Signaling through cAMP regulates most cellular functions. The spatiotemporal control of cAMP is, therefore, crucial for differential regulation of specific cellular targets. Here we investigated the consequences of PDE4B or PDE4D gene ablation on cAMP signaling at a subcellular level using mouse embryonic fibroblasts. PDE4B ablation had no effect on the global or bulk cytosol accumulation of cAMP but increased both basal and hormone-dependent cAMP in a near-membrane pool. Conversely, PDE4D ablation enhanced agonist-induced cAMP accumulation in the bulk cytosol as well as at the plasma membrane. Both PDE4B and PDE4D ablation significantly modified the time course and the level of isoproterenol-induced phosphorylation of vasodilator-stimulated phosphoprotein, a membrane cytoskeletal component. A second membrane response through Toll-like receptor signaling, however, was only affected by PDE4B ablation. PDE4D but not PDE4B ablation significantly prolonged cAMP-response element-binding protein-mediated transcription. These findings demonstrate that PDE4D and PDE4B have specialized functions in mouse embryonic fibroblasts with PDE4B controlling cAMP in a discrete subdomain near the plasma membrane.

Signaling from beta1- and beta2-adrenergic receptors is defined by differential interactions with PDE4.

Beta1- and beta2-adrenergic receptors (betaARs) are highly homologous, yet they play clearly distinct roles in cardiac physiology and pathology. Myocyte contraction, for instance, is readily stimulated by beta1AR but not beta2AR signaling, and chronic stimulation of the two receptors has opposing effects on myocyte apoptosis and cell survival. Differences in the assembly of macromolecular signaling complexes may explain the distinct biological outcomes. Here, we demonstrate that beta1AR forms a signaling complex with a cAMP-specific phosphodiesterase (PDE) in a manner inherently different from a beta2AR/beta-arrestin/PDE complex reported previously. The beta1AR binds a PDE variant, PDE4D8, in a direct manner, and occupancy of the receptor by an agonist causes dissociation of this complex. Conversely, agonist binding to the beta2AR is a prerequisite for the recruitment of a complex consisting of beta-arrestin and the PDE4D variant, PDE4D5, to the receptor. We propose that the distinct modes of interaction with PDEs result in divergent cAMP signals in the vicinity of the two receptors, thus, providing an additional layer of complexity to enforce the specificity of beta1- and beta2-adrenoceptor signaling.

Enoxaparin Use and Adverse Events in Outpatients With a Continuous Flow Left Ventricular Assist Device at a Single Institution.

BACKGROUND: Patients with left ventricular assist devices (LVADs) are anticoagulated with warfarin and may receive enoxaparin bridging for a subtherapeutic international normalized ratio (INR). There is no guideline regarding enoxaparin bridging in LVAD patients and a dosing strategy to ensure efficacy and safety is uncertain. OBJECTIVE: The objective was to characterize the use of enoxaparin bridging for subtherapeutic INRs and its impact on thrombotic or major bleeding events (MBE) in patients with an LVAD. METHODS: A retrospective review from 6/1/17 to 6/30/18 was performed. Patients with an LVAD were excluded if they had less than 60 days of outpatient anticoagulation or age <18 years old. Patients were divided into 2 cohorts based on enoxaparin exposure. MBE and thrombotic events were classified as related to enoxaparin if events occurred while receiving enoxaparin and up to 7 days or 30 days, respectively, after discontinuation. RESULTS: Seventy-one LVAD patients met inclusion criteria and 50 patients received enoxaparin bridging. Therapeutic-dose enoxaparin was initiated at a mean INR of 1.8 for a mean duration of 2.8 days. In the enoxaparin exposure group, one MBE occurred 6 days after enoxaparin discontinuation, coinciding with an INR increase from 1.8 to 4.7. One thrombotic event occurred 2 days after enoxaparin discontinuation at an INR of 5.0. CONCLUSION: This institution's bridging strategy of therapeutic-dose enoxaparin with a short duration has a low rate of bleeding and thrombotic events. Additional prospective studies of anticoagulation bridging based on characteristics such as type of LVAD device are warranted.

Luteinizing hormone-dependent activation of the epidermal growth factor network is essential for ovulation.

In the preovulatory ovarian follicle, mammalian oocytes are maintained in prophase meiotic arrest until the luteinizing hormone (LH) surge induces reentry into the first meiotic division. Dramatic changes in the somatic cells surrounding the oocytes and in the follicular wall are also induced by LH and are necessary for ovulation. Here, we provide genetic evidence that LH-dependent transactivation of the epidermal growth factor receptor (EGFR) is indispensable for oocyte reentry into the meiotic cell cycle, for the synthesis of the extracellular matrix surrounding the oocyte that causes cumulus expansion, and for follicle rupture in vivo. Mice deficient in either amphiregulin or epiregulin, two EGFR ligands, display delayed or reduced oocyte maturation and cumulus expansion. In compound-mutant mice in which loss of one EGFR ligand is associated with decreased signaling from a hypomorphic allele of the EGFR, LH no longer signals oocyte meiotic resumption. Moreover, induction of genes involved in cumulus expansion and follicle rupture is compromised in these mice, resulting in impaired ovulation. Thus, these studies demonstrate that LH induction of epidermal growth factor-like growth factors and EGFR transactivation are essential for the regulation of a critical physiological process such as ovulation and provide new strategies for manipulation of fertility.

Generation of mouse oocytes defective in cAMP synthesis and degradation: endogenous cyclic AMP is essential for meiotic arrest.

Although it is established that cAMP accumulation plays a pivotal role in preventing meiotic resumption in mammalian oocytes, the mechanisms controlling cAMP levels in the female gamete have remained elusive. Both production of cAMP via GPCRs/Gs/adenylyl cyclases endogenous to the oocyte as well as diffusion from the somatic compartment through gap junctions have been implicated in maintaining cAMP at levels that preclude maturation. Here we have used a genetic approach to investigate the different biochemical pathways contributing to cAMP accumulation and maturation in mouse oocytes. Because cAMP hydrolysis is greatly decreased and cAMP accumulates above a threshold, oocytes deficient in PDE3A do not resume meiosis in vitro or in vivo, resulting in complete female infertility. In vitro, inactivation of Gs or downregulation of the GPCR GPR3 causes meiotic resumption in the Pde3a null oocytes. Crossing of Pde3a(-/-) mice with Gpr3(-/-) mice causes partial recovery of female fertility. Unlike the complete meiotic block of the Pde3a null mice, oocyte maturation is restored in the double knockout, although it occurs prematurely as described for the Gpr3(-/-) mouse. The increase in cAMP that follows PDE3A ablation is not detected in double mutant oocytes, confirming that GPR3 functions upstream of PDE3A in the regulation of oocyte cAMP. Metabolic coupling between oocytes and granulosa cells was not affected in follicles from the single or double mutant mice, suggesting that diffusion of cAMP is not prevented. Finally, simultaneous ablation of GPR12, an additional receptor expressed in the oocyte, does not modify the Gpr3(-/-) phenotype. Taken together, these findings demonstrate that Gpr3 is epistatic to Pde3a and that fertility as well as meiotic arrest in the PDE3A-deficient oocyte is dependent on the activity of GPR3. These findings also suggest that cAMP diffusion through gap junctions or the activity of additional receptors is not sufficient by itself to maintain the meiotic arrest in the mouse oocyte.

Effect of chronic estradiol administration on vimentin and GFAP immunohistochemistry within the inner ear.

Recent data show that hormone replacement therapy, involving estrogen together with progestin, can promote hearing loss (Guimaraes, P., Frisina, S.T., Mapes, F., Tadros, S.F., Frisina, D.R. and Frisina, R.D., 2006. Progestin negatively affects hearing in aged women. Proc. Natl. Acad. Sci. USA. 103, 14246-14249.). But long-term estradiol treatment, which induces hyperprolactinemia in guinea pigs, results in hearing loss and bone dysmorphology of the otic capsule-without much hair cell loss (Horner, K.C., Cazals, Y., Guieu, R., Lenoir, M. and Sauze, N., 2007. Experimental estrogen-induced hyperprolactinemia results in bone-related hearing loss in the guinea pig. Am. J. Physiol., Endocrinol. Metab. 293, E1224-1232.). Since estrogen receptor beta can protect the mouse cochlea against acoustic trauma (Meltser, I., Tahera, Y., Simpson, E., Hultcrantz, M., Charitidi, K., Gustafsson, J.A. and Canlon, B., 2008. Estrogen receptor beta protects against acoustic trauma in mice. J. Clin. Invest. 118, 1563-1570.), we hypothesized that estradiol might activate protective glial-like elements in the inner ear. Immunohistochemistry showed down-regulation of vimentin within the lateral wall and upregulation within the spiral limbus. Glial fibrillary acid protein was increased in the inner sulcus, Hensen cells and Claudius cells. Furthermore, there was increased expression of vimentin in type II cells of the spiral ganglion and type I vestibular hair cells. The observations suggested that estradiol treatment may affect the inner ear ionic homeostasis but protection may be afforded via activated intermediate filaments.

A specific pattern of phosphodiesterases controls the cAMP signals generated by different Gs-coupled receptors in adult rat ventricular myocytes.

Compartmentation of cAMP is thought to generate the specificity of Gs-coupled receptor action in cardiac myocytes, with phosphodiesterases (PDEs) playing a major role in this process by preventing cAMP diffusion. We tested this hypothesis in adult rat ventricular myocytes by characterizing PDEs involved in the regulation of cAMP signals and L-type Ca2+ current (I(Ca,L)) on stimulation with beta1-adrenergic receptors (beta1-ARs), beta2-ARs, glucagon receptors (Glu-Rs) and prostaglandin E1 receptors (PGE1-Rs). All receptors but PGE1-R increased total cAMP, and inhibition of PDEs with 3-isobutyl-1-methylxanthine strongly potentiated these responses. When monitored in single cells by high-affinity cyclic nucleotide-gated (CNG) channels, stimulation of beta1-AR and Glu-R increased cAMP, whereas beta2-AR and PGE1-R had no detectable effect. Selective inhibition of PDE3 by cilostamide and PDE4 by Ro 20-1724 potentiated beta1-AR cAMP signals, whereas Glu-R cAMP was augmented only by PD4 inhibition. PGE1-R and beta2-AR generated substantial cAMP increases only when PDE3 and PDE4 were blocked. For all receptors except PGE1-R, the measurements of I(Ca,L) closely matched the ones obtained with CNG channels. Indeed, PDE3 and PDE4 controlled beta1-AR and beta2-AR regulation of I(Ca,L), whereas only PDE4 controlled Glu-R regulation of I(Ca,L) thus demonstrating that receptor-PDE coupling has functional implications downstream of cAMP. PGE1 had no effect on I(Ca,L) even after blockade of PDE3 or PDE4, suggesting that other mechanisms prevent cAMP produced by PGE1 to diffuse to L-type Ca2+ channels. These results identify specific functional coupling of individual PDE families to Gs-coupled receptors as a major mechanism enabling cardiac cells to generate heterogeneous cAMP signals in response to different hormones.

Clinical and Financial Outcomes Evaluation of Multimodal Pharmacist Warfarin Management of a Statewide Urban and Rural Population.

PURPOSE: To evaluate the efficacy, safety, and indirect financial outcomes of pharmacist face-to-face warfarin management with telephone-based distance management utilizing local laboratories or patient self-testing (PST). METHODS: A retrospective analysis of a clinic population of 336 patients on established warfarin therapy distributed statewide in rural and urban settings over a 6-month period was conducted. Participants were stratified into face-to-face management, telephone-based management utilizing local laboratory testing, and telephone-based management utilizing PST. RESULTS: The primary outcome of international normalized ratio (INR) time in therapeutic range (TTR) for face-to-face management was significantly greater than distance management utilizing local laboratory testing (69.0% vs 60.5%, P = .0032). No difference was observed between face-to-face management and PST (69.0% vs 68.0%, P = .25). No significant difference in bleeding or thromboses was observed. Although increased clinician time was utilized during face-to-face encounters compared to telephone encounters (8.7-minute face-to-face, 5.5-minute local laboratory, and 5.4-minute PST), face-to-face encounters tended to be billable at lower levels, whereas telephone-based encounters were billable at higher levels. CONCLUSION: A multimodal approach to pharmacist warfarin management of a patient population distributed statewide in rural and urban locations is effective despite TTR differences associated with INR testing used in distance management. PST may improve warfarin treatment outcomes and adherence in distance management, particularly when the use of alternative oral anticoagulants is inappropriate. Although time and billing differences between face-to-face and distance management exist, clinical and safety outcomes remain acceptable despite encounter complexity and support reimbursement of pharmacist anticoagulation management in all settings.

Comparing Clinical Outcomes of a Pharmacist-Managed Diabetes Clinic to Usual Physician-Based Care.

BACKGROUND: This study analyzed the impact of a pharmacist-managed diabetes clinic on clinical outcomes compared to usual care received from primary care providers (PCPs). This comparison may more definitively demonstrate the value of pharmacist management of chronic disease states. METHODS: Retrospective observational cohort study conducted in patients referred to a pharmacist-managed pharmacotherapy (PT) clinic from July 2009 to October 2014. RESULTS: For the primary outcome, the absolute change in A1c during the usual care phase was +1.53% (95% confidence interval [CI]: 1.10-1.96, P < .0001) versus an absolute change of -1.63% (95% CI: -1.28 to -1.97, P < .0001) in the intervention phase. For secondary outcomes, diabetes-related hospitalizations (10 vs 6, P = .104) and emergency room (ER) visits (27 vs 8, P = .049) decreased in the intervention phase compared to the usual care phase. The rate of diabetes-related interventions made per patient per year in the usual care phase was 2.7 versus 11.1 in the intervention phase ( P < .0001). CONCLUSION: Patients referred to the PT clinic had worsening blood glucose control prior to referral, and their control improved after referral to the clinic. Furthermore, there was an improvement in all diabetes-related outcomes in the intervention phase compared to the usual care phase.

Cyclic nucleotide phosphodiesterase 3A-deficient mice as a model of female infertility.

Since cAMP blocks meiotic maturation of mammalian and amphibian oocytes in vitro and cyclic nucleotide phosphodiesterase 3A (PDE3A) is primarily responsible for oocyte cAMP hydrolysis, we generated PDE3A-deficient mice by homologous recombination. The Pde3a(-/-) females were viable and ovulated a normal number of oocytes but were completely infertile, because ovulated oocytes were arrested at the germinal vesicle stage and, therefore, could not be fertilized. Pde3a(-/-) oocytes lacked cAMP-specific PDE activity, contained increased cAMP levels, and failed to undergo spontaneous maturation in vitro (up to 48 hours). Meiotic maturation in Pde3a(-/-) oocytes was restored by inhibiting protein kinase A (PKA) with adenosine-3',5'-cyclic monophosphorothioate, Rp-isomer (Rp-cAMPS) or by injection of protein kinase inhibitor peptide (PKI) or mRNA coding for phosphatase CDC25, which confirms that increased cAMP-PKA signaling is responsible for the meiotic blockade. Pde3a(-/-) oocytes that underwent germinal vesicle breakdown showed activation of MPF and MAPK, completed the first meiotic division extruding a polar body, and became competent for fertilization by spermatozoa. We believe that these findings provide the first genetic evidence indicating that resumption of meiosis in vivo and in vitro requires PDE3A activity. Pde3a(-/-) mice represent an in vivo model where meiotic maturation and ovulation are dissociated, which underscores inhibition of oocyte maturation as a potential strategy for contraception.

Stress hormones in Ménière's disease and acoustic neuroma.

Stress has been postulated to trigger or contribute to inner ear pathologies but there is little objective evidence. We investigated stress hormones in Ménière's patients and patients with acoustic neuroma. Data were compared with those from a control group of patients with facial spasm. We assayed classic stress hormones including adrenocorticotropic hormone, cortisol, growth hormone and prolactin. We found a strong positive correlation between cortisol and adrenocorticotropic hormone in Ménière patients and patients with acoustic neuroma but no correlation in patients with facial spasm. The data also revealed in female patients with Ménière's disease or with acoustic neuroma an unexpected significant positive correlation between cortisol and prolactin. The data showed the expected negative correlation or no correlation between cortisol and prolactin associated with males and females in the other patient groups. Both cortisol and prolactin increases are known to represent alternative strategies to cope with stress, and our data point to prolactin being possibly more dominant in Ménière's disease and cortisol in acoustic neuroma. These data provide further evidence for modification of different stress hormones in audiovestibular pathologies, which might provide a valuable diagnostic or prognostic tool in the future.

Hyperprolactinemia in some Meniere patients even in the absence of incapacitating vertigo.

Stress can be a significant factor influencing ear pathologies and is often reported to trigger the symptoms of Meniere's disease. Both physiological and psychological stress provokes the release of prolactin from the pituitary thus allowing the classification of prolactin as a major stress hormone. We investigated the level of the stress hormone prolactin in a Swedish population with early symptoms of Meniere's disease. The median prolactin level in the Meniere patients (n=33) was not significantly different from that of non-Meniere patients (n=23). However, in the Meniere group one female (90 year old) had prolactin levels in the upper normal range for women, one male (77 year old) had prolactin levels above the normal limit for men, and a third patient (76 year old female) presented hyperprolactinemia with more than twice the normal level. MRI confirmed a pituitary adenoma in this patient. This study provides further support for the recent report of hyperprolactinemia in some patients with long-standing Meniere's disease and presenting incapacitating vertigo in France. The data emphasize the likely implication of stress in this pathology where the stress hormone prolactin is likely to represent one actor in a complex hormonal imbalance affecting the inner ear.

Phosphodiesterase regulation is critical for the differentiation and pattern of gene expression in granulosa cells of the ovarian follicle.

Feedback regulations are integral components of the cAMP signaling required for most cellular processes, including gene expression and cell differentiation. Here, we provide evidence that one of these feedback regulations involving the cyclic nucleotide phosphodiesterase PDE4D plays a critical role in cAMP signaling during the differentiation of granulosa cells of the ovarian follicle. Gonadotropins induce PDE4D mRNA and increase the cAMP hydrolyzing activity in granulosa cells, demonstrating that a feedback regulation of cAMP is operating in granulosa cells in vivo. Inactivation of the PDE4D by homologous recombination is associated with an altered pattern of cAMP accumulation induced by the gonadotropin LH/human chorionic gonadotropin (hCG), impaired female fertility, and a markedly decreased ovulation rate. In spite of a disruption of the cAMP response, LH/hCG induced P450 side chain cleavage expression and steroidogenesis in a manner similar to wild-type controls. Morphological examination of the ovary of PDE4D-/- mice indicated luteinization of antral follicles with entrapped oocytes. Consistent with the morphological finding of unruptured follicles, LH/hCG induction of genes involved in ovulation, including cyclooxygenase-2, progesterone receptor, and the downstream genes, is markedly decreased in the PDE4D-/- ovaries. These data demonstrate that PDE4D regulation plays a critical role in gonadotropin mechanism of action and suggest that the intensity and duration of the cAMP signal defines the pattern of gene expression during the differentiation of granulosa cells.

Prolactinoma in some Ménière's patients--is stress involved?

Dizziness is a common complaint in primary care clinics and can enter the diagnostic profile of different pathologies spanning from psychiatric problems to vestibular dysfunction. Episodes of vertigo in Ménière's patients are often reported to be triggered by stress but no physiological data are available to account for the subjective link. The study involved 42 Ménière's patients hospitalized for neurectomy of the vestibular nerve for relief of incapacitating vertigo. In addition 18 patients with neurinoma of the vestibular nerve and 12 patients with facial spasm, who underwent surgery, served as controls. A blood sample was taken on the day of surgery in order to determine the level of battery of different stress hormones. The most striking observation was the presence of hyperprolactinemia (above 20 microg/l) in 14 Ménière's patients. The presence of prolactinoma was confirmed by MRI in six cases out of six investigated and the others have not yet been followed up in this retrospective study. These observations are clearly indicative for systematic determination of prolactin levels before opting for surgery in Ménière's patients.

Role of cyclic nucleotide signaling in oocyte maturation.

The development of the ovarian follicle, oocyte maturation, and ovulation require a complex set of endocrine, paracrine, and autocrine inputs that are translated into the regulation of cyclic nucleotide levels. Changes in intracellular cAMP mediate the gonadotropin regulation of granulosa and theca cell functions. Likewise, a decrease in cAMP concentration in the oocyte has been associated with the resumption of meiosis. Using pharmacological and molecular approaches, we determined that the expression of cyclic nucleotide phosphodiesterases (PDEs), the enzymes that degrade and inactivate cAMP, is compartmentalized in the ovarian follicle of all species studied, with PDE3 present in the oocytes and PDE4s in granulosa cells. The PDE3 expressed in the mouse oocyte was cloned, and the protein expressed in a heterologous system had properties similar to those of a PDE3A derived from somatic cells. Inhibition of the oocyte PDE3 completely blocked oocyte maturation in vitro and in vivo, demonstrating that the activity of this enzyme is essential for oocyte maturation. Heterologous expression of PDE3A in Xenopus oocyte causes morphological changes distinctive of resumption of meiosis (GVBD), as well as activation of mos translation and MAPK phosphorylation. Using mRNA and antibody microinjection in the Xenopus eggs, we have shown that PDE3 is downstream from the kinase PKB/Akt in the pathway that mediates IGF-1 but not progesterone-induced meiotic resumption. The presence of a similar regulatory module in mammalian oocytes is inferred by pharmacological studies with PDE3 inhibitors and measurement of PDE activity. Thus, PDE3 plays an essential role in the signaling pathway that controls resumption of meiosis in amphibians and mammals. Understanding the regulation of this enzyme may shed some light on the signals that trigger oocyte maturation.

Similar half-octave TTS protection of the cochlea by xylazine/ketamine or sympathectomy.

Cochlear efferents, sympathetic control and stress conditions have been shown to influence sound-induced hearing loss. These factors are also known to be modified by sedation/anesthesia. We tested here the effect of sedation/anesthesia on temporary threshold shift (TTS) compared to that in the same awake animals. The effect of sympathectomy was also tested. We employed awake guinea pigs with a chronically implanted electrode on the round window of each of the cochleae. Each ear was tested for its sensitivity to TTS induced by a 1 min or a 10 min exposure to an 8 kHz pure tone at 96 dB sound pressure level. After an intramuscular injection of xylazine or ketamine together with xylazine, TTS at half-octave frequencies was reduced compared to that in awake animals. The second half-octave frequencies were less affected. This specific pattern of protection was also observed here after surgical ablation of a superior cervical ganglion. The data lead to the speculation that protection from TTS under sedation/anesthesia might be due to diminished sympathetic influence. Xylazine is a pre-synaptic alpha2-adrenoreceptor agonist which blocks noradrenaline release from the sympathetic system. Ketamine is a N-methyl-D-aspartic acid receptor antagonist which could reduce glutamate excitotoxicity as well as reduce sympathetic activity.

Evaluation of dosing and clinical outcomes in patients undergoing conversion of insulin glargine to insulin detemir.

STUDY OBJECTIVES: To evaluate the dose and frequency of insulin detemir for patients with diabetes mellitus undergoing conversion from insulin glargine to insulin detemir, and to assess glycemic control, weight gain, and risk of hypoglycemia after converting to insulin detemir. DESIGN: Retrospective medical record review. SETTING: Large academic medical center. PATIENTS: Thirty-one patients with type 1 (10 patients) or type 2 (21 patients) diabetes who were converted from insulin glargine to insulin detemir by usual practice between January 1, 2006, and March 3, 2007, after an Iowa Medicaid formulary switch. MEASUREMENT AND MAIN RESULTS: Data were collected for 12 months after conversion from insulin glargine to insulin detemir. No significant change in mean basal insulin dose was noted in patients with type 1 diabetes at the end of 12 months (insulin detemir 31.1 units/day vs baseline insulin glargine 32.0 units/day, p=0.89; insulin detemir 0.41 unit/kg/day vs baseline insulin glargine 0.42 unit/kg/day, p=0.91). In patients with type 2 diabetes, however, the mean basal insulin dose was significantly higher with insulin detemir compared with baseline insulin glargine (74.2 vs 55.8 units/day, p=0.002; 0.68 vs 0.48 unit/kg/day, p=0.001) at the end of 12 months. Twice-daily administration was required in a higher proportion of patients receiving insulin detemir (15 patients [48%]) at 12 months compared with insulin glargine (4 patients [13%]) at baseline (p=0.043). A significant change in hemoglobin A(1c) was not observed in patients with type 1 diabetes (9.7% with insulin detemir vs 9.3% with insulin glargine, p=0.41) or type 2 diabetes (9.4% with insulin detemir vs 9.7% with insulin glargine at baseline, p=0.57) despite the use of higher insulin detemir doses in patients with type 2 diabetes. No significant differences in weight or frequency of hypoglycemia were noted. CONCLUSION: Treatment with insulin detemir appears to require more frequent administration and higher insulin doses compared with insulin glargine in patients with type 2 diabetes, with 33% higher doses, on average, observed in this study. These findings suggest that a unit-for-unit conversion from insulin glargine to insulin detemir, as suggested by the manufacturer of insulin detemir, may not be adequate in patients with type 2 diabetes.

Somatic cells regulate maternal mRNA translation and developmental competence of mouse oocytes.

Germ cells divide and differentiate in a unique local microenvironment under the control of somatic cells. Signals released in this niche instruct oocyte reentry into the meiotic cell cycle. Once initiated, the progression through meiosis and the associated programme of maternal messenger RNA translation are thought to be cell autonomous. Here we show that translation of a subset of maternal mRNAs critical for embryo development is under the control of somatic cell inputs. Translation of specific maternal transcripts increases in oocytes cultured in association with somatic cells and is sensitive to EGF-like growth factors that act only on the somatic compartment. In mice deficient in amphiregulin, decreased fecundity and oocyte developmental competence is associated with defective translation of a subset of maternal mRNAs. These somatic cell signals that affect translation require activation of the PI(3)K-AKT-mTOR pathway. Thus, mRNA translation depends on somatic cell cues that are essential to reprogramme the oocyte for embryo development.