PTSD in women is associated with a block in conversion of progesterone to the GABAergic neurosteroids allopregnanolone and pregnanolone measured in plasma.

There is a need to identify new and more effective treatments for posttraumatic stress disorder (PTSD). Allopregnanolone and its stereoisomer pregnanolone (together termed ALLO) are metabolites of progesterone that positively and allosterically modulate GABA effects at GABAA receptors, thereby reducing anxiety and depression. Previous research revealed that women with PTSD had low cerebrospinal fluid (CSF) ALLO levels and a low ratio of ALLO to the allopregnanolone precursor 5α-DHP, consistent with deficient activity of the ALLO synthetic enzyme 3α-hydroxysteroid dehydrogenase (3α-HSD). The current study examined ALLO and the ratio of ALLO to 5α-DHP in plasma at rest and in response to psychophysiological stressors in trauma-exposed, medication-free women with and without PTSD. Participants were examined twice in random order during the early follicular phase (eFP) and mid-luteal phase (mLP) of the menstrual cycle. Plasma neurosteroids were measured using gas chromatography-mass spectrometry. Results indicate that the ALLO to 5α-DHP ratio in plasma increases between the eFP and mLP. In addition, women with PTSD have a lower ratio of ALLO to 5α-DHP than trauma-exposed healthy women, as well as blunted increases in this ratio in response to a moderately stressful laboratory procedure, i.e., differential fear conditioning, across the menstrual cycle. Clinically feasible testing for 3α-HSD dysfunction is critical to translating this line of research into clinical care. Measurement of this ratio in plasma could facilitate patient stratification in clinical treatment trials, as well as precision medicine targeting of treatments that address ALLO synthesis deficits in women with PTSD.

Paranasal sinus masses of Rocky Mountain bighorn sheep (Ovis canadensis canadensis).

This article describes 10 cases of paranasal sinus masses in Rocky Mountain bighorn sheep (Ovis canadensis canadensis). Among 21 bighorns that were examined from 11 herds in Colorado, 10 individuals (48%) from 4 herds (36%) had masses arising from the paranasal sinuses. Affected animals included 9 of 17 females (53%) and 1 of 4 males (25%), ranging in age from approximately 2 years to greater than 10 years. Defining gross features of these masses included unilateral or bilateral diffuse thickening of the respiratory lining of the maxillary and/or frontal sinuses, with abundant seromucinous exudate in the affected sinus cavities. Defining histologic features of these masses included chronic inflammation and proliferation of mesenchymal and epithelial cells of the mucosa and submucosa. Epithelial changes included hyperplasia of mucosal epithelium, hyperplasia of submucosal glands and ducts, and neoplasia (adenocarcinoma). Mesenchymal changes included submucosal myxedema, submucosal fibroplasia/fibrosis, bone destruction, and neoplasia (myxomatous fibroma). Specific immunohistochemistry and polymerase chain reaction for Jaagsiekte sheep retrovirus and enzootic nasal tumor virus were performed with negative results.

Experimental chronic wasting disease (CWD) in the ferret.

Chronic wasting disease (CWD), a prion disease of North American deer, elk and moose, affects both free-ranging and captive cervids. The potential host range for CWD remains uncertain. The susceptibility of the ferret to CWD was examined experimentally by administering infectious brain material by the intracerebral (IC) or oral (PO) route. Between 15 and 20 months after IC inoculation, ferrets developed neurological signs consistent with prion disease, including polyphagia, somnolence, piloerection, lordosis and ataxia. Upon first sub-passage of ferret-adapted CWD, the incubation period decreased to 5 months. Spongiform change in the neuropil was most marked in the basal ganglia, thalamus, midbrain and pons. The deposition of PrP(CWD) was granular and was occasionally closely associated with, or localized within, neurons. There were no plaque-like or perivascular PrP aggregates as seen in CWD-infected cervids. In western blots, the PrP(CWD) glycoform profile resembled that of CWD in deer, typified by a dominant diglycosylated glycoform. CWD disease in ferrets followed IC but not PO inoculation, even after 31 months of observation. These findings indicate that CWD-infected ferrets share microscopical and biochemical features of CWD in cervids, but appear to be relatively resistant to oral infection by primary CWD inoculum of deer origin.

Nerve growth factor neuroprotection of ethanol-induced neuronal death in rat cerebral cortex is age dependent.

Organotypic cultures of rat cortex were used to test the hypotheses that nerve growth factor (NGF) is neuroprotective for immature cortical neurons and that ethanol abolishes this neuroprotection in a developmental stage-dependent manner. Samples were obtained on gestational day (G) 16 or postnatal day (P) 3 and cultured with ethanol (0 or 400 mg/dl) and NGF (0 or 30 ng/ml) for 72 h. Dying neurons were identified as exhibiting terminal nick-end labeling, immunoreactivity for activated caspase 3, or condensed nuclear chromatin. Two cortical compartments were examined in fetal tissue: a superficial, cell-sparse marginal zone (MZ) and a cell-dense cortical plate (CP). At P3, the CP was subdivided into a cell-dense upper cortical plate (UCP) and a less densely packed lower cortical plate (LCP). Neuronal death in the MZ was affected by neither NGF nor ethanol at both ages. In the fetal CP, NGF did not affect the incidence of cell death, but ethanol increased it. Treatment with NGF caused an upregulation of the expression of Neg, a gene known to be affected by NGF and ethanol. NGF did not ameliorate the ethanol-induced death. In pups, ethanol increased the amount of death in the LCP. NGF did protect against this death. Neither ethanol nor NGF altered the incidence of cell death in the UCP. The laminar-dependent neuroprotection did not correlate with expression of NGF receptors or Neg. Thus, NGF can be protective against the neurotoxic effect of ethanol in the neonatal brain. This effect is site selective and time dependent and it targets postmigratory, differentiating neurons.

Morphology offers no clues to asexual vs. sexual origin of small Acropora cervicornis (Scleractinia: Acroporidae) colonies / La morfología no ofrece pistas sobre el origen asexual o sexual de las colonias pequeñas de Acropora cervicornis (Scleractinia: Acroporidae)

Sexual recruitment of the staghorn coral, Acropora cervicornis, is accepted to be very rare. Instead, these branching corals proliferate through fragmentation leading to dense mono-specific and possibly monoclonal stands. For acroporid corals, which have suffered drastic population declines, dominance of asexual reproduction results in low levels of genotypic diversity and limited ability to re-colonize extirpated areas. Small colonies with a single encrusting, symmetrical base, and few incipient branches are frequently presumed to be the result of a settled planula (i.e. sexual reproduction). Here, we show that colonies fitting this description (i.e., presumed sexual recruits) can result from asexual fragmentation. Acropora cervicornis colonies (~20 cm diameter) were tagged and observed over eighteen months. In several cases, colony offshoots fused with the adjacent substrate forming secondary disc-like attachment points. Following natural fragmentation, these discs of tissue became separated from the original colony, and were observed to heal and give rise to smaller colonies with striking similarity to the expected morphology of a sexual recruit. Thus, presuming a colony is a sexual recruit based on appearance is unreliable and may lead to inflated expectations of genetic diversity among populations. The accurate assessment of recruitment and genetic diversity is crucial to predicting the recovery potential of these imperiled and ecologically irreplaceable reef corals. Rev. Biol. Trop. 54 (Suppl. 3): 145-151. Epub 2007 Jan. 15.

Se ha aceptado que el reclutamiento sexual del coral asta de venado, Acropora cervicornis, es muy raro. Por el contrario, estos corales ramificados proliferan a través de fragmentación, generando densas bases monoespecíficas e incluso monoclonales. Para corales acropóridos, los cuales han sufrido disminuciones de población drásticas, la dominancia de reproducción asexual resulta en bajos niveles de diversidad genotípica y abilidad limitada para recolonizar áreas de donde han sido erradicados. Frecuentemente se presume que las colonias pequeñas con una sola base incrustante simétrica y unas pocas ramas incipientes, son el resultado del asentamiento de una plánula (reproducción sexual). Aquí, nosotros demostramos que algunas colonias que calzan con esta descripción (supuesta reproducción sexual) pueden resultar de fragmentación asexual. Se etiquetaron y observaron colonias de Acropora cervicornis (~20 cm de diámetro) durante 18 meses. En muchos casos, los retoños de la colonia se fusionaron con el sustrato adyacente formando puntos de acoplamiento con forma de disco. Siguiendo con la fragmentación natural, estos discos de tejido se separaron de la colonia original, cicatrizaron y dieron paso a pequeñas colonias con tremenda similitud a la morfología esperada para un recluta sexual. Por lo tanto, asumir que una colonia es un recluta de origen sexual basándose en apariencia es poco fiable y puede generar expectativas infladas de diversidad genética entre poblaciones. La evaluación certera del reclutamiento y la diversidad genética es crucial para predecir la recuperación potencial de estos arrecifes de coral, los cuales están en peligro y son irremplazables.

Proliferation and death of conditionally immortalized neural cells from murine neocortex: p53 alters the ability of neuron-like cells to re-enter the cell cycle.

Neurons are distinctive in that they are generally considered to be permanently post-mitotic cells. The oncoprotein p53 is a key regulator in neuronal development, notably in cell proliferation and neuronal death. We hypothesize that p53 maintains the post-mitotic characteristic of differentiated neurons. New lines of conditionally immortalized cortical cells were generated to test this hypothesis. Populations of cells were obtained from the neocortices of dual transgenic mice that were null for p53 and expressed a temperature-sensitive SV40 large T antigen. At a permissive temperature (32 degrees C), the cells continued to proliferate and most expressed nestin and proteins associated with glia. At a non-permissive temperature (39 degrees C), the cells expressed cytoskeletal proteins associated with differentiated neurons such as microtubule associated protein 2 and neurofilament 200. Under permissive conditions, both p53(+/-) and p53(-/-) cells exhibited similar cycling behaviors; the length of the cell cycle was 13-15 h and >85% of the cells were actively cycling. In non-permissive conditions, most p53(+/-) cells stopped dividing, whereas the p53(-/-) cells continued to proliferate. The survival of the cells also differed. In the non-permissive conditions, many p53(+/-) cells died following treatment with a neurotoxin (ethanol, 400 mg/dl), whereas the p53(-/-) cells did not. After re-introduction to the permissive conditions, both cell lines expressed neuron-like characteristics, but only the p53(-/-) cells retained their ability to cycle. Therefore, p53-mediated activities appear to be involved in the proliferation, survival, and post-mitotic nature of neuron-like cells.

Hyperthermic teratogenicity, thermal dose and diagnostic ultrasound during pregnancy: implications of new standards on tissue heating.

Hyperthermia is a recognized teratogen in mammalian laboratory animals and is a suspected teratogen for humans. The purpose of this synopsis is to reanalyse existing data on hyperthermia-induced teratogenic effects in experimental mammalian systems in terms of a thermal dose (temperature:time) concept, and then to illustrate the utility of this concept to human situations involving potential thermal increments to post-implantation embryos and foetuses. For example, the threshold temperature elevation for hyperthermia-induced teratogenic effects in experimental mammals is estimated (but not rigorously tested) to be approximately 1.5 degrees C above core values for exposures of long duration, possibly with a thermal dose of approximately 5 min duration or more at 4 degrees C. This level of tissue temperature increment is within the capability of some modern diagnostic ultrasound (DUS) devices sold within the USA and abroad. Epidemiological studies have not indicated any hazard from the use of DUS, but such studies are limited in sensitivity and were conducted with DUS devices whose acoustic outputs were relatively low compared to those presently available. After a regulatory change that allowed for substantially increased acoustic outputs, modern DUS devices were mandated to provide the user with on-screen information (the Thermal Index, or 'TI') about ultrasound-induced temperature increments in the target tissue. The TI is generally accurate to within a factor of 2, but the factor may be as high as 6 in certain obstetric settings. Thus, informed use of and attention to the TI is strongly advised, with this admonition gaining increased emphasis if the present regulations regarding allowable acoustic outputs of DUS devices were to be further relaxed or eliminated.

Effects of prenatal exposure to ethanol on the expression of bcl-2, bax and caspase 3 in the developing rat cerebral cortex and thalamus.

Prenatal exposure to ethanol causes neuronal death in somatosensory cortex, but apparently not in the ventrobasal nucleus of the thalamus. Effectors such as bcl-2, bax, and caspase 3 can determine whether a neuron survives or dies. We hypothesize that ethanol differentially affects the expression of these proteins in the cortex and thalamus during the periods of naturally occurring and ethanol-induced neuronal death. Pregnant rats were fed ad libitum with an ethanol-containing liquid diet (Et) or pair-fed an isocaloric non-alcoholic diet (Ct). Samples were collected from fetuses (gestational day (G) 16 and G19) and pups (postnatal day (P) 0 through P30) and examined for bcl-2, bax, or caspase 3 expression using a quantitative immunoblotting procedure. Prenatal exposure to ethanol reduced cortical bcl-2 expression, but not bax expression on P6. Hence, the bcl-2/bax ratio was lower in Et-treated rats than in controls. In contrast, thalamic expression of neither bcl-2 nor bax was significantly different in the two groups of rats. Thus, the thalamic bcl-2/bax ratio was unaffected by exposure to ethanol. During the period of naturally occurring neuronal death, the expression of the active (20 kDa) and inactive isoforms (32 kDa) of caspase 3 was altered in the cortices of Et-treated rats, but not in their thalami. Thus, prenatal exposure to ethanol affected the early postnatal expression of death-related proteins in the cortex, but not in the thalamus. These biochemical changes concur with anatomical data on the spatial and temporal selectivity of ethanol toxicity in the developing CNS.

Use of galactosyltransferase to assess the biological function of O-linked N-acetyl-d-glucosamine: a potential role for O-GlcNAc during cell division.

Many cytosolic and nuclear proteins are modified by monomeric O-linked N-acetyl-d-glucosamine (O-GlcNAc). The biological functions of this form of glycosylation are unclear but evidence suggests that it heightens regulation of protein function. To assess the biological function of O-GlcNAc addition, we examined the biological effects of galactosyltransferase (GalT) microinjected into the cytoplasm of Xenopus ovarian oocytes. GalT, which catalyzes beta1-4-galactose addition to O-GlcNAc, should inhibit deglycosylation and lectin-like interactions requiring unmodified O-GlcNAc residues. Although GalT injection into diplotene-arrested oocytes has no detectable effects on cell viability, it is toxic to oocytes entering meiosis. Cell-cycle-specific toxicity is recapitulated in vitro as GalT inhibits formation of nuclei and microtubule asters from cell-free extracts of ovulated frog eggs. These observations suggest that regulation of O-GlcNAc is important for cell cycle progression and may be important in diseases in which O-GlcNAc metabolism is abnormal. The methods described here outline a viable experimental scheme for ascribing a biological function to this form of glycosylation.

Ethanol enhances erbB-mediated migration of human breast cancer cells in culture.

Growth factor systems (ligands and their receptors) are targets of ethanol toxicity. Inasmuch as alcohol consumption may increase the risk and development of breast cancer, we hypothesize that ethanol enhances cell migration by up-regulating the activities of erbB receptors. Of the three tested breast cancer cell lines that exhibit low invasion capacity (BT-20, MCF-7, and T47D cells), erbB receptors were specifically affected by ethanol only in the T47D cells. Ethanol increased erbB2, erbB3, and erbB4 expression in T47D human breast cancer cells in a concentration-dependent manner. ErbB1 (epidermal growth factor receptor) was unaffected. Heregulin beta 1 (ligand for erbB3 and erbB4) induced a modest increase in the invasion potential of the T47D cells. Ethanol alone also promoted modest invasion by the T47D cells, however, ethanol dramatically increased their heregulin-mediated invasion. Knocking-out erbB2 with an anti-sense oligonucleotide eliminated heregulin beta 1-promoted migration and blocked ethanol-induced chemo-migration. Thus, these data suggest that alcohol may enhance metastasis by altering an erbB system, and pivotally, erbB2.

Expression of bcl-2, bax, and caspase-3 in the brain of the developing rat.

Naturally occurring neuronal death (NOND) is generally considered to be apoptotic. Apoptosis is an active form of cell death in which the regulation of specific proteins produces anti- or pro-apoptotic signals. Two of the protein families involved in this regulation are the bcl proteins and caspases. A quantitative immunoblotting technique was used to examine the temporal expression of bcl-2, bax, and two isoforms of caspase 3 (an active 20 kDa isoform and the inactive 32 kDa precursor) throughout the developing neuraxis. Long-Evans rat fetuses were collected on gestational day (G) 16 and G19, and pups were harvested on postnatal day (P) 0, P3, P6, P12, P21, and P30. Brains were divided into five segments: cortex, thalamus, midbrain, medulla/pons, and cerebellum. In general, the expression of bax increased and the ratio of bcl-2 expression to bax expression decreased concurrent with published data on the onset of NOND in a given area. The timing of these events was paralleled by an increase in the expression of active caspase 3. Unlike the bcl proteins, caspase 3 expression returned toward fetal levels as the brain matured. The timing of the changes in bcl protein and caspase expression show that both protein families are involved in promoting neuronal death. Reductions in caspase expression (and not bcl-2 and bax expression) are key to ending the period of NOND.

HIV-1 rev depolymerizes microtubules to form stable bilayered rings.

We describe a novel interaction between HIV-1 Rev and microtubules (MTs) that results in the formation of bilayered rings that are 44-49 nm in external diameter, 3.4-4.2 MD (megadaltons) in mass, and have 28-, 30-, or 32-fold symmetry. Ring formation is not sensitive to taxol, colchicine, or microtubule-associated proteins, but requires Mg(2+) and is inhibited by maytansine. The interaction involves the NH(2)-terminal domain of Rev and the face of tubulin exposed on the exterior of the MTs. The NH(2)-terminal half of Rev has unexpected sequence similarity to the tubulin-binding portion of the catalytic/motor domains of the microtubule-destabilizing Kin I kinesins. We propose a model wherein binding of Rev dimers to MTs at their ends causes segments of two neighboring protofilaments to peel off and close into rings, circumferentially containing 14, 15, or 16 tubulin heterodimers, with Rev bound on the inside. Rev has a strong inhibitory effect on aster formation in Xenopus egg extracts, demonstrating that it can interact with tubulin in the presence of normal levels of cellular constituents. These results suggest that Rev may interact with MTs to induce their destabilization, a proposition consistent with the previously described disruption of MTs after HIV-1 infection.

Neurotrophin receptors in the somatosensory cortex of the mature rat: co-localization of p75, trk, isoforms and c-neu.

Trk immunoreactivity is expressed by a discrete population of cortical neurons, primarily those with cell bodies in layer Vb and dendrites in supragranular cortex. We tested the hypothesis that neurons co-express multiple isoforms of trk receptors. The distribution of neurons expressing specific high affinity neurotrophin receptors was determined immunohistochemically. Multiple antibodies directed against each trk isoform and an antibody directed against an epitope shared by all three trk isoforms were used. The distribution of neurons expressing each of the three receptors was virtually identical. Each anti-trk antibody primarily labeled neurons with cell bodies in layer V. More than one-third of layer V neurons was positive for a high affinity trk receptor. Few immunoreactive somata (1%-5%) were in the other layers. In addition, the neuropil in the supragranular laminae was immunopositive for each trk isoform. Recent data show that layer V neurons in the mature somatosensory cortex express the tyrosine kinase receptor c-erbB2, also known as c-neu. Immunofluorescence double labeling shows that approximately 80% of the c-neu-immunolabeled neurons in layer V co-expressed pan-trk immunoreactivity and two-thirds of all c-neu-positive neurons expressed a specific trk isoform. We concluded from these data that there is significant co-expression of trk isoforms in layer V neurons. In summary, trkA, trkB, trkC, and c-neu were primarily expressed by cortical projection neurons in layer V and co-expression among these receptors was common. This implies that cortical growth factor systems are redundant and that cortical neurons are responsive to more than one growth factor.

A canine model of multiple portosystemic shunting.

The objective of this study was to develop and describe an experimental canine model of multiple acquired portosystemic shunts (PSS) similar in nature to spontaneously occurring PSS. Sixteen dogs were used and were divided into a control (n = 6) and a diseased group (n = 10). Dogs of the diseased group were administered dimethylnitrosamine (2 mg/kg of body weight, po) twice weekly, and clinicopathologic, ultrasonographic, and hepatic scintigraphic findings were recorded during the development of hepatic disease and PSS. Surgery was then performed to permit visual verification of multiple shunts, catheter placement for portography examination, and biopsy of the liver. All diseased dogs developed severe hepatic disease and multiple PSS as documented visually at surgery and on portography. Based on this study, dimethylnitrosamine-induced portosystemic shunting appears to be an appropriate model for spontaneously occurring multiple PSS secondary to portal hypertension.

Platelet-derived growth factor-mediated signal transduction underlying astrocyte proliferation: site of ethanol action.

Platelet-derived growth factor (PDGF) is a critical regulator of cell proliferation. Because ethanol inhibits cell proliferation in vivo and in vitro, we hypothesize that ethanol-induced inhibition results from differential interference with signal transduction pathways activated by PDGF. Cultured cortical astrocytes were used to examine the effects of ethanol on PDGF-mediated signal transduction, on the expression of two PDGF monomers (A- and B-chains), and on the expression of two PDGF receptor subunits (PDGFalphar and PDGFbetar). PDGF-B chain homodimer (PDGF-BB), and to a lesser extent PDGF-A chain homodimer (PDGF-AA), stimulated the proliferation of astrocytes raised in a serum-free medium. Ethanol attenuated these actions in a concentration-dependent manner. Ethanol inhibited both PDGF-AA- and PDGF-BB-mediated phosphorylation of PDGFalphar, but it had little effect on PDGFbetar autophosphorylation. Likewise, ethanol abolished the association of PDGFalphar to Ras GTPase-activating protein (Ras-GAP), but it did not affect the binding of Ras-GAP to PDGFbetar. PDGF stimulated the activities of mitogen-activated protein kinase (MAPK) in protein kinase C (PKC) independent and dependent manners. Ethanol inhibited the PKC-independent, acute activation of MAPK; however, it stimulated the PKC-dependent, sustained activation of MAPK. The expression of neither ligand was altered by exposure to ethanol for 3 d. Moreover, such treatment specifically upregulated PDGFalphar expression in a concentration-dependent manner. It did not, however, affect the binding affinity of either receptor. Thus, the signal transduction pathways initiated by PDGF-AA and PDGF-BB were differentially affected by ethanol. This differential vulnerability resulted from the preferential effects of ethanol on PDGFalphar autophosphorylation. Hence, ethanol-induced alterations are transduced through specific receptors of mitogenic growth factors.

Transforming growth factor beta1-regulated cell proliferation and expression of neural cell adhesion molecule in B104 neuroblastoma cells: differential effects of ethanol.

The expression and activity of factors influencing early neuronal development are altered by ethanol. Such factors include growth factors, for example, platelet-derived growth factor and basic fibroblast growth factor (for cell proliferation), and cell adhesion molecules (for neuronal migration). One agent, transforming growth factor beta1 (TGFbeta1), may affect both events. We tested the hypothesis that ethanol alters myriad TGFbeta1-mediated activities [i.e., cell proliferation and neural cell adhesion molecule (N-CAM) expression] using B104 neuroblastoma cells. TGFbeta1 inhibited the proliferation of B104 cells as evidenced by decreases in cell number and [3H]thymidine ([3H]dT) incorporation. TGFbeta1 induced sustained activation of extracellular signal-regulated kinases (ERKs), which are part of the family of mitogen-activated protein kinases (MAPKs). Treatment with PD98059 (a MAPK kinase blocker) abolished TGFbeta1-regulated inhibition of [3H]dT incorporation. TGFbeta1-mediated growth inhibition was potentiated by ethanol exposure. Ethanol also produced prolonged activation of ERK, an effect that was partially eliminated by treatment with PD98059. On the other hand, TGFbeta1 up-regulated N-CAM expression, and this up-regulation was not affected by treatment with PD98059. Ethanol inhibited the TGFbeta1-induced up-regulation of N-CAM expression in a concentration-dependent manner. Thus, TGFbeta1 affects ERK-dependent cell proliferation and ERK-independent N-CAM expression in B104 cells. Both activities are sensitive to ethanol and may underlie the ethanol-induced alterations in the proliferation and migration of CNS neurons.

Phosphorylation and glycosylation of nucleoporins.

The nuclear pore complex mediates macromolecular transport between the nucleus and cytoplasm. Many nuclear pore components (nucleoporins) are modified by both phosphate and O-linked N-acetylglucosamine (O-GlcNAc). Among its many functions, protein phosphorylation plays essential roles in cell cycle progression. The role of O-GlcNAc addition is unknown. Here, levels of nucleoporin phosphorylation and glycosylation during cell cycle progression are examined. Whereas nuclear pore glycoproteins are phosphorylated in a cell-cycle-dependent manner, levels of O-GlcNAc remain constant. The major nucleoporin p62 can be phosphorylated in vitro by protein kinase A and glycogen synthase kinase (GSK)-3alpha but not by cyclin B/cdc2 or GSK-3beta. The consensus sites of these kinases resemble sites which can be glycosylated by O-GlcNAc transferase. These data are consistent with a model that O-GlcNAc limits nucleoporin hyperphosphorylation during M-phase and hastens the resumption of regulated nuclear transport at the completion of cell division.

Utility of produce ratios to track fruit and vegetable consumption in a rural community, church-based 5 A Day intervention project.

Previous research suggests that grocery store characteristics may be useful in evaluating community-based dietary interventions. We undertook a study to determine whether produce ratios (ratios of produce sales to total grocery sales) were a useful indicator of fruit and vegetable (F & V) consumption in a church-based, community intervention trial that promoted 5 A Day guidelines within 10 rural counties of North Carolina. Produce ratios were collected from stores identified by participants in the Black Churches United for Better Health Project. Baseline and study period data for 21 stores in intervention counties and 18 stores in nonintervention counties were compared using repeated-measures analysis of variance. Produce ratios were significantly associated with seasonality (p < 0.0001), but no differences were seen between the two groups of stores. These findings do not support data from individual telephone surveys, which showed significant differences in F & V consumption between participants in the two groups. Our inability to detect differences at the store level may have been due to 1) the incapacity of produce ratios to capture F & V purchases that were juice, frozen, or canned products; 2) shifts in procuring F & Vs from grocery stores to other sources (i.e., gleaning and produce cooperatives); 3) the modest proportion of shoppers that received the full intervention dose; and 4) a general lack of power to detect differences at the store level. Therefore, although produce ratios did not serve as a valid measure for this project, if their limitations are recognized and compensated for, they may have applicability for future investigations that monitor F & V consumption.

Expression of nerve growth factor, p75, and the high affinity neurotrophin receptors in the adult rat trigeminal system: evidence for multiple trophic support systems.

We hypothesize that discrete trigeminal structures have the components required for autocrine regulation as well as redundant neurotrophin support systems. We examined the expression of nerve growth factor (NGF) and the low affinity (p75) and high affinity (trkA, trkB, and trkC) neurotrophin receptors in the trigeminal system of adult rats. Four sites were examined; the trigeminal ganglion, mesencephalic nucleus, principal sensory nucleus (PSN), and trigeminal motor nucleus. NGF was expressed by more than 60% of neurons in each area studied. NGF immunolabeling may have resulted from exogenous protein incorporated from the microenvironment or from NGF synthesized by the neuron per se. To resolve this issue, in situ hybridization for NGF mRNA was performed. The mRNA was expressed by 2/3 to 7/8 of neurons in trigeminal structures. Moreover, double-labeling studies showed that virtually every ganglion cell that was NGF-immunoreactive also expressed the NGF transcript. Neurotrophin receptors (p75 and trk isoforms) were expressed by more than 60% of the neurons in each trigeminal structure. The only exception was the PSN, where the receptors were expressed by fewer than half of the neurons. Taken together, these data imply that NGF must be elaborated by neurons that co-express both p75 and trkA. Therefore, each trigeminal structure has the machinery for autocrine/paracrine regulation, as well as the capacity for retrograde and/or anterograde trophic support. Furthermore, the co-expression of the specific trk isoforms indicates that trigeminal neurons are sensitive to more than one neurotrophin.