Preliminary assessment of groundwater hydrogeochemistry within Gilan, a northern province of Iran.

In four basins of Gilan province, groundwater samples were collected from 127 piezometric wells to investigate the hydrogeochemistry of groundwater, and additionally its suitability for drinking and irrigation purposes. The average concentrations of major cations and anions follow the order of Ca2+ > Na+ > Mg2+ > K+ and [Formula: see text], respectively. Using Piper diagram delineation, CaMgHCO3 was determined as the main hydrogeochemical facies of groundwater. According to Piper diagrams, Gibbs plots, and ionic ratios, silicate weathering and ion exchange are the major processes regulating the groundwater hydrochemistry. Furthermore, saturation indices (SIs) revealed that carbonate precipitation also plays an important role in aquifers. Among the processes, weathering of silicate minerals seems to be the dominant process. Comparing the analyzed major ions and physicochemical parameters with the WHO guideline values indicates that the potability of most groundwater samples is generally acceptable. Electrical conductivity (EC) and total dissolved solid (TDS) measurements along with sodium percentage (SP), sodium adsorption ratio (SAR), Kelley's index (KI), and residual sodium carbonate (RSC) calculations suggest that groundwater in many areas is suitable for irrigation use. Nonetheless, total hardness (TH) values ranging as high as 650.0 mg/l reveal many groundwater samples to be classified as hard and very hard, indicating a requirement for long-term monitoring and further evaluation. The present study shows that the groundwater quality in Lahijan, Astaneh, and to a lesser extent Fouman drainage basins is lower than in Talesh. Therefore, intense monitoring programs towards enhanced water management practices are recommended before poorer quality groundwater is further utilized.

Exome sequencing in 32 patients with anophthalmia/microphthalmia and developmental eye defects.

Anophthalmia/microphthalmia (A/M) is a genetically heterogeneous birth defect for which the etiology is unknown in more than 50% of patients. We used exome sequencing with the ACE Exome(TM) (Personalis, Inc; 18 cases) and UCSF Genomics Core (21 cases) to sequence 28 patients with A/M and four patients with varied developmental eye defects. In the 28 patients with A/M, we identified de novo mutations in three patients (OTX2, p.(Gln91His), RARB, p.Arg387Cys and GDF6, p.Ala249Glu) and inherited mutations in STRA6 in two patients. In patients with developmental eye defects, a female with cataracts and cardiomyopathy had a de novo COL4A1 mutation, p.(Gly773Arg), expanding the phenotype associated with COL4A1 to include cardiomyopathy. A male with a chorioretinal defect, microcephaly, seizures and sensorineural deafness had two PNPT1 mutations, p.(Ala507Ser) and c.401-1G>A, and we describe eye defects associated with this gene for the first time. Exome sequencing was efficient for identifying mutations in pathogenic genes for which there is no clinical testing available and for identifying cases that expand phenotypic spectra, such as the PNPT1 and COL4A1-associated disorders described here.

Pyrrolo- and pyridomorphinans: non-selective opioid antagonists and delta opioid agonists/mu opioid partial agonists.

Opioid ligands have found use in a number of therapeutic areas, including for the treatment of pain and opiate addiction (using agonists) and alcohol addiction (using antagonists such as naltrexone and nalmefene). The reaction of imines, derived from the opioid ligands oxymorphone and naltrexone, with Michael acceptors leads to pyridomorphinans with structures similar to known pyrrolo- and indolomorphinans. One of the synthesized compounds, 5e, derived from oxymorphone had substantial agonist activity at delta opioid receptors but not at mu and/or kappa opioid receptors and in that sense profiled as a selective delta opioid receptor agonist. The pyridomorphinans derived from naltrexone and naloxone were all found to be non-selective potent antagonists and as such could have utility as treatments for alcohol abuse.

Inducible cyclooxygenase may have anti-inflammatory properties.

Cyclooxygenase (COX) has two isoforms. Generally, COX 1 is constitutively expressed in most tissues, where it maintains physiological processes; inducible COX 2 is considered a pro-inflammatory enzyme and a chief target for the treatment of inflammatory diseases. Here we present evidence that COX 2 may have anti-inflammatory properties. In carrageenin-induced pleurisy in rats, the predominant cells at 2 hours are polymorphonuclear leucocytes, whereas mononuclear cells dominate from 24 hours until resolution at 48 hours. In this model, COX 2 protein expression peaked initially at 2 hours, associated with maximal prostaglandin E2 synthesis. However, at 48 hours there was a second increase in COX 2 expression, 350% greater than that at 2 hours. Paradoxically, this coincided with inflammatory resolution and was associated with minimal prostaglandin E2 synthesis. In contrast, levels of prostaglandin D2, and 15deoxy delta(12-14)prostaglandin J2 were high at 2 hours, decreased as inflammation increased, but were increased again at 48 hours. The selective COX 2 inhibitor NS-398 and the dual COX 1/COX 2 inhibitor indomethacin inhibited inflammation at 2 hours but significantly exacerbated inflammation at 48 hours. This exacerbation was associated with reduced exudate prostaglandin D2 and 15deoxy delta(12-14)prostaglandin J2 concentrations, and was reversed by replacement of these prostaglandins. Thus, COX 2 may be pro-inflammatory during the early phase of a carrageenin-induced pleurisy, dominated by polymorphonuclear leucocytes, but may aid resolution at the later, mononuclear cell-dominated phase by generating an alternative set of anti-inflammatory prostaglandins.

Infrequent recovery of HIV from but robust exogenous infection of activated CD4(+) T cells in HIV elite controllers.

BACKGROUND. Human immunodeficiency virus (HIV) elite controllers are able to control infection with HIV-1 spontaneously to undetectable levels in the absence of antiretroviral therapy, but the mechanisms leading to this phenotype are poorly understood. Although low frequencies of HIV-infected peripheral CD4(+) T cells have been reported in this group, it remains unclear to what extent these are due to viral attenuation, active immune containment, or intracellular host factors that restrict virus replication. METHODS. We assessed proviral DNA levels, autologous viral growth from and infectability of in vitro activated, CD8(+) T cell-depleted CD4(+) T cells from HIV elite controllers (mean viral load, <50 copies/mL), viremic controllers (mean viral load, <2000 copies/mL), chronic progressors, and individuals receiving highly active antiretroviral therapy. RESULTS. Although we successfully detected autologous virus production in ex vivo activated CD4(+) T cells from all chronic progressors and from most of the viremic controllers, we were able to measure robust autologous viral replication in only 2 of 14 elite controllers subjected to the same protocol. In vitro activated autologous CD4(+) T cells from elite controllers, however, supported infection with both X4 and R5 tropic HIV strains at comparable levels to those in CD4(+) T cells from HIV-uninfected subjects. Proviral DNA levels were the lowest in elite controllers, suggesting that extremely low frequencies of infected cells contribute to difficulty in isolation of virus. CONCLUSIONS. These data indicate that elite control is not due to inability of activated CD4(+) T cells to support HIV infection, but the relative contributions of host and viral factors that account for maintenance of low-level infection remain to be determined.

Reputational ratings of doctoral programs.

Peer ratings of the quality of doctoral program faculties were obtained in a 1975 national survey of chemistry, history, and psychology programs. The ratings were then compared to those obtained 6 and 11 years earlier by the American Council on Education. In general, the rankings obtained from the ratings proved to be highly stable over the 11-year period, particularly in chemistry and history. Some ratings were also obtained for subspecialties within the three disciplines. Though it is clear that variations in quality among subspecialty faculties do exist and are important for individual program evaluations, it is unlikely that such subspecialty ratings would be feasible or useful in national surveys of the reputations of doctoral programs. The ratings were found to be highly related to a number of research-oriented variables of departments (such as size, productivity, percentage of alumni holding academic positions at Ph.D.-granting universities), but unrelated or very weakly related to such features as the student-reported quality of teaching and degree of faculty concern for students, or faculty-reported degree of departmental effort toward the career development of junior members of the faculty.

Endogenous regulators of G protein signaling differentially modulate full and partial mu-opioid agonists at adenylyl cyclase as predicted by a collision coupling model.

Regulator of G protein signaling (RGS) proteins accelerate the endogenous GTPase activity of Galpha(i/o) proteins to increase the rate of deactivation of active Galpha-GTP and Gbetagamma signaling molecules. Previous studies have suggested that RGS proteins are more effective on less efficiently coupled systems such as with partial agonist responses. To determine the role of endogenous RGS proteins in functional responses to mu-opioid agonists of different intrinsic efficacy, Galpha(i/o) subunits with a mutation at the pertussis toxin (PTX)-sensitive cysteine (C351I) and with or without a mutation at the RGS binding site (G184S) were stably expressed in C6 glioma cells expressing a mu-opioid receptor. Cells were treated overnight with PTX to inactivate endogenous G proteins. Maximal inhibition of forskolin-stimulated adenylyl cyclase by the low-efficacy partial agonists buprenorphine and nalbuphine was increased in cells expressing RGS-insensitive Galpha(o)(CIGS), Galpha(i2)(CIGS), or Galpha(i3)(CIGS) compared with their Galpha(CI) counterparts, but the RGS-insensitive mutation had little or no effect on the maximal inhibition by the higher efficacy agonists DAMGO and morphine. The potency of all the agonists to inhibit forskolin-stimulated adenylyl cyclase was increased in cells expressing RGS-insensitive Galpha(o)(CIGS), Galpha(i2)(CIGS), or Galpha(i3)(CIGS), regardless of efficacy. These data are comparable with predictions based on a collision coupling model. In this model, the rate of G protein inactivation, which is modulated by RGS proteins, and the rate of G protein activation, which is affected by agonist intrinsic efficacy, determine the maximal agonist response and potency at adenylyl cyclase under steady state conditions.

Pattern recognition receptors and interleukin-8 mediate effects of Gram-positive and Gram-negative bacteria on lung epithelial cell function.

BACKGROUND AND PURPOSE: Lung epithelial cells express pattern recognition receptors, which react to bacteria. We have evaluated the effect of Gram-positive and Gram-negative bacteria on interleukin-8 (CXCL8) release from epithelial cells and the integrity of the epithelial barrier. EXPERIMENTAL APPROACH: Primary cultures of human airway epithelial cells and the epithelial cell line A549 were used, and CXCL8 release was measured after exposure to Gram-negative or Gram-positive bacteria. Epithelial barrier function was assessed in monolayer cultures of A549 cells. RESULTS: Gram-positive bacteria Staphylococcus aureus or Streptococcus pneumoniae, induced release of CXCL8 from human airway epithelial cells. These bacteria also disrupted barrier function in A549 cells, an effect mimicked by CXCL8 and blocked by specific binding antibodies to CXCL8. Gram-negative bacteria Escherichia coli or Pseudomonas aeruginosa induced greater release of CXCL8 than Gram-positive bacteria. However, Gram-negative bacteria did not affect epithelial barrier function directly, but prevented disruption induced by Gram-positive bacteria. These effects of Gram-negative bacteria on barrier function were mimicked by FK565, an agonist of the nucleotide-binding oligomerization domain 1 (NOD1) receptor, but not by the Toll-like receptor (TLR) 4 agonist bacterial lipopolysaccharide. Neither the Gram-negative bacteria nor FK565 blocked CXCL8 release. CONCLUSIONS: These data show differential functional responses induced by Gram-negative and Gram-positive bacteria in human lung epithelial cells. The NOD1 receptors may have a role in preventing disruption of the epithelial barrier in lung, during inflammatory states.

Cigarette smoke inhibits macrophage sensing of Gram-negative bacteria and lipopolysaccharide: relative roles of nicotine and oxidant stress.

BACKGROUND AND PURPOSE: Smoking cigarettes is a major risk factor for the development of cardiovascular and respiratory disease. Moreover, smokers are more prone to infections. This has been associated with a suppression of the immune system by smoke. However, it is not clear how cigarette smoke affects the ability of immune cells to sense pathogens. Cigarette smoke contains a large number of molecules which may mediate responses on immune cells and of these, nicotine and oxidants have both been identified as inhibitory for the sensing of bacterial lipopolysaccharide (LPS). Nitric oxide synthase (NOS) and tumour necrosis factor (TNF)-alpha are both induced in macrophages on stimulation with Gram negative bacteria or LPS. EXPERIMENTAL APPROACH: We used murine macrophages stimulated with whole heat-killed bacteria or LPS. We measured output of NO (as nitrite) and TNFalpha, NOS protein by Western blotting and cellular oxidant stress. KEY RESULTS: Cigarette smoke extract suppressed the ability of murine macrophages to release NO, but not TNFalpha in response to whole bacteria. Cigarette smoke extract also inhibited nitric oxide synthase II protein expression in response to LPS. The effects of cigarette smoke extract on nitrite formation stimulated by LPS were unaffected by inhibition of nicotinic receptors with alpha-bungarotoxin (100 units ml(-1)). However, the effects of cigarette smoke extract on LPS-induced nitrite formation were mimicked by hydrogen peroxide and reversed by the anti-oxidants N-acetyl cysteine and glutathione. CONCLUSIONS AND IMPLICATIONS: We suggest that cigarette smoke exerts its immunosuppressive effects through an oxidant-dependent and not a nicotine-dependent mechanism.

Development, implementation, and effects of an integrated web-based teaching model in a nursing ethics course.

BACKGROUND: Ethical competence, which is reflected in the ability to detect ethical challenges in clinical situations and engage in deliberate thinking on ethical actions, is one of the core competencies of nursing practice. PURPOSE: The purpose of this study was to develop and implement an interactive situational e-learning system, integrating nursing ethical decisions into a nursing ethics course, and to evaluate the effects of this course on student nurses' ethical decision-making competence. PROJECT DESIGN: The project was designed to be carried out in two phases. In the first phase, an interactive situated e-learning system was developed and integrated into the nursing ethics course. The second phase involved implementing the course and evaluating its effects in a quasi-experimental study. The course intervention was designed for 2h per week over one semester (18weeks). PARTICIPANTS: A total of 100 two-year technical college nursing students in their second year of the program participated in the study, with 51 in the experimental group and 49 in the control group. RESULTS: After completing the course, the students in the experimental group showed significant improvement in nursing ethical decision-making competence, including skills in "raising questions," "recognizing differences," "comparing differences," "self-dialogue," "taking action," and "identifying the implications of decisions made," compared to their performance prior to the class. After controlling for factors influencing learning effects, students in the experimental group showed superiority to those in the control group in the competency of "recognizing differences." The students in the experimental group reported that the course pushed them to search for and collect information needed to resolve the ethical dilemma. CONCLUSIONS: The interactive situational e-learning system developed by our project was helpful in developing the students' competence in ethical reasoning. The e-learning system and the situational teaching materials used in this study may be applicable in nursing and related professional ethics courses.

Effects of injectable trace minerals on humoral and cell-mediated immune responses to Bovine viral diarrhea virus, Bovine herpes virus 1 and Bovine respiratory syncytial virus following administration of a modified-live virus vaccine in dairy calves.

Our objective was to evaluate the effect of an injectable trace mineral (ITM) supplement containing zinc, manganese, selenium, and copper on the humoral and cell mediated immune (CMI) responses to vaccine antigens in dairy calves receiving a modified-live viral (MLV) vaccine containing BVDV, BHV1, PI3V and BRSV. A total of 30 dairy calves (3.5 months of age) were administered a priming dose of the MLV vaccine containing BHV1, BVDV1 & 2, BRSV, PI3V, and an attenuated-live Mannheimia-Pasteurella bacterin subcutaneously (SQ). Calves were randomly assigned to 1 of 2 groups: (1) administration of ITM SQ (ITM, n=15) or (2) injection of sterile saline SQ (Control; n=15). Three weeks later, calves received a booster of the same vaccine combination SQ, and a second administration of ITM, or sterile saline, according to the treatment group. Blood samples were collected on days 0, 7, 14, 21, 28, 42, 56, and 90 post-vaccination for determination of antibody titer, viral recall antigen-induced IFN-γ production, and viral antigen-induced proliferation by peripheral blood mononuclear cells (PBMC). Administration of ITM concurrently with MLV vaccination resulted in higher antibody titers to BVDV1 on day 28 after priming vaccination compared to the control group (P=0.03). Calves treated with ITM showed an earlier enhancement in PBMC proliferation to BVDV1 following vaccination compared to the control group. Proliferation of PBMC after BVDV stimulation tended to be higher on day 14 after priming vaccination in calves treated with ITM than in the control group (P=0.08). Calves that received ITM showed higher PBMC proliferation to BRSV stimulation on day 7 after priming vaccination compared to the control group (P=0.01). Moreover, calves in the ITM group also had an enhanced production IFN-γ by PBMC after stimulation with BRSV on day 21 after priming vaccination compared to day 0 (P<0.01). In conclusion, administration of ITM concurrently with MLV vaccination in dairy calves resulted in increased antibody titer to BVDV1, and greater PBMC proliferation to BVDV1 and BRSV recall stimulation compared to the control group, suggesting that ITM might represent a promising tool to enhance the humoral and CMI responses to MLV vaccines in cattle.

Dominant effects of the bcr-abl oncogene on Drosophila morphogenesis.

We targeted expression of human/fly chimeric Bcr-Abl proteins to the developing central nervous system (CNS) and eye imaginal disc of Drosophila melanogaster. Neural expression of human/fly chimeric P210 Bcr-Abl or P185 Bcr-Abl rescued abl mutant flies from pupal lethality, indicating that P210 and P185 Bcr-Abl can substitute functionally for Drosophila Abl during axonogenesis. However, increased levels of neurally expressed P210 or P185 Bcr-Abl but not Drosophila Abl produced CNS defects and lethality. Expression of P210 or P185 in the eye imaginal disc produced a dominant rough eye phenotype that was dependent on dosage of the transgene. Drosophila Enabled, previously identified as a suppressor of the abl mutant phenotype and substrate for Drosophila Abl kinase, had markedly increased phosphotyrosine levels in Bcr-Abl expressing Drosophila, indicating that it is a substrate for Bcr-Abl as well. Drosophila, therefore, is a suitable model system to identify Bcr-Abl interactions important for signal transduction and oncogenesis.

Neuronal/lymphoid membrane glycoprotein MRC OX-2 is a member of the immunoglobulin superfamily with a light-chain-like structure.

The MRC OX-2 antigen is a membrane glycoprotein of about 45,000 Mr present on rat neurons, thymocytes, B cells, follicular dendritic cells, endothelium and smooth muscle. Sequence of cDNA clones indicates it is a member of the Ig superfamily containing 248 amino acids organized like an Ig light chain with a V-like domain and a C-like domain followed by a transmembrane and cytoplasmic sections. There is a sequence with homologies with J-regions but analysis of the gene for human OX-2 shows that this is part of the V-domain exon and there is not a separate J-region exon as in the T cell receptor or Ig chains. The relationship of OX-2 to the other Ig-related neuronal/thymocyte antigen Thy-1 and the evolution of the Ig superfamily are discussed.

Coupling of multiple opioid receptors to GTPase following selective receptor alkylation in brain membranes.

Opioid agonists of the mu, kappa and delta types stimulated low-Km guanosine triphosphatase (GTPase) in membranes, from the brain of the rat by up to 34%, with potencies the rank order of which corresponded to the respective binding affinities to opioid receptor. In general, kappa ligands stimulated GTPase to a lesser degree than mu or delta opiates. The coupling of a given type of opioid receptor to GTPase was resolved by direct or protective alkylation of the other receptors. Treatment of the membranes with beta-funaltrexamine abolished the stimulation of GTPase by sufentanil and levorphanol (mu), but not by bremazocine (kappa) or DSLET (delta). On the other hand, prior incubation with Superfit, an alkylating agent with selectivity for the delta opioid receptor, specifically eliminated the effect of DSLET. Partial alkylation by increasing concentrations of Superfit gradually reduced the extent of stimulation of GTPase by DSLET. The successive treatment of membranes with Superfit and beta-funaltrexamine blocked the actions of DSLET, sufentanil and levorphanol, but had no effect on the stimulation of the GTPase by bremazocine. Selective coupling of an opioid receptor to GTPase was also obtained after incubation of membranes with beta-chlornaltrexamine in the presence of protective concentrations of mu, kappa or delta opioid ligands. Alkylation resolved the coupling of the non-selective opiate etorphine: the sum of stimulation of GTPase in the receptor-selective membranes equalled maximal stimulation of enzyme in untreated membranes. Naloxone blocked the stimulation of GTPase by mu, kappa or delta agonists, but ICI-174,864 specifically inhibited the effect of DSLET.(ABSTRACT TRUNCATED AT 250 WORDS)

Gene expression and localization of GABA(C) receptors in neurons of the rat gastrointestinal tract.

The effects of GABA in the CNS are mediated by three different GABA receptors: GABA(A), GABA(B) and GABA(C) receptors. GABA(A) and GABA(B) receptors, but not yet GABA(C) receptors, have been demonstrated in the enteric nervous system, where GABA has been proposed to be a transmitter. The purpose of this study was to determine whether GABA(C) receptors are present and thus may play a role in mediating the effects of GABA in the myenteric plexus of the rat gastrointestinal tract. We examined the expression of the three known GABA(C) receptor subunits, rho1, rho2 and rho3, in the rat duodenum, ileum and colon using the reverse transcriptase-polymerase chain reaction. We determined the localization of GABA(C) receptors in the myenteric plexus of these regions using two different antisera directed against GABA(C) receptor subunits. The polymerase chain reaction revealed that all three subunits were expressed in the gastrointestinal tract. When the layers of the intestine were separated and the layer containing myenteric neurons was assayed, the rho3 subunit was found in the ileum and colon, whereas rho1 was expressed in the duodenum and weakly in the colon and rho2 was expressed in the ileum. Immunocytochemistry revealed numerous labeled neurons in the myenteric plexus of each region. Colocalization showed that a large proportion of calbindin plus calretinin immunoreactive neurons (intrinsic primary afferent neurons) were immunoreactive for the GABA(C) receptor, and that 56% of nitric oxide synthase immunoreactive neurons (inhibitory motor neurons) exhibited the receptor. These results indicate that GABA(C) receptors of differing subunit compositions are expressed by neurons in the rat gastrointestinal tract. The effects of GABA on intrinsic sensory and on inhibitory motor neurons are likely to be mediated in part through GABA(C) receptors.

Mu and Delta opioid receptors activate the same G proteins in human neuroblastoma SH-SY5Y cells.

1. There is evidence for interactions between mu and delta opioid systems both in vitro and in vivo. This work examines the hypothesis that interaction between these two receptors can occur intracellularly at the level of G protein in human neuroblastoma SH-SY5Y cells. 2. The [(35)S]GTP gamma S binding assay was used to measure G protein activation following agonist occupation of opioid receptors. The agonists DAMGO (EC(50), 45 nM) and SNC80 (EC(50), 32 nM) were found to be completely selective for stimulation of [(35)S]-GTP gamma S binding through mu and delta opioid receptors respectively. Maximal stimulation of [(35)S]-GTP gamma S binding produced by SNC80 was 57% of that seen with DAMGO. When combined with a maximally effective concentration of DAMGO, SNC80 caused no additional [(35)S]-GTP gamma S binding. This effect was also seen when measured at the level of adenylyl cyclase. 3. Receptor activation increased the dissociation of pre-bound [(35)S]-GTP gamma S. In addition, the delta agonist SNC80 promoted the dissociation of [(35)S]-GTP gamma S from G proteins initially labelled using the mu agonist DAMGO. Conversely, DAMGO promoted the dissociation of [(35)S]-GTP gamma S from G proteins initially labelled using SNC80. 4. Tolerance to DAMGO and SNC80 in membranes from cells exposed to agonist for 18 h was homologous and there was no evidence for alteration in G protein activity. 5. The findings support the hypothesis that mu- and delta-opioid receptors share a common G protein pool, possibly through a close organization of the two receptors and G protein at the plasma membrane.

Management of dystocia caused by a large sacrococcygeal teratoma.

Sacrococcygeal teratoma is a rare cause of dystocia. Reported management strategies to date have yielded few viable infants. In this case report, the infant was partially delivered when extraction was halted. The infant was intubated and resuscitated while preparations for emergency cesarean section were being made. The infant was subsequently delivered abdominally and three years later is normal. Despite absent thoracic cage movement during resuscitation, adequate oxygenation was possible. Increasing use of prenatal ultrasonography should allow early detection, and thus avoid such unanticipated dystocias.

Diabetes guidelines: a summary and comparison of the recommendations of the American Diabetes Association, Veterans Health Administration, and American Association of Clinical Endocrinologists.

OBJECTIVE: This paper summarizes and compares 3 major organizations' guidelines for the management of diabetes mellitus. BACKGROUND: Diabetes mellitus is a chronic disease that affects >16 million Americans. A decrease in adverse events has been demonstrated when hyperglycemia and comorbid conditions such as hypertension and dyslipidemia are controlled in patients with diabetes. Although each patient with diabetes is unique and medical care should be tailored to his or her individual needs, clinical evidence and expert opinion have established a baseline level of care for all patients with diabetes. Guidelines have been created to guide practitioners in selecting appropriate care, but their length and complexity may serve as barriers to their use. METHODS: The diabetes management guidelines of the American Diabetes Association (ADA), Veterans Health Administration (VA), and American Association of Clinical Endocrinologists (AACE) are summarized and compared in both text and tabular form. CONCLUSION: Although the guidelines published by the ADA, VA, and AACE vary slightly, all of them can be used to ensure that patients with diabetes receive appropriate care.

Selectivity of ligand binding to opioid receptors in brain membranes from the rat, monkey and guinea pig.

Conditions for the equilibrium binding to opioid receptor of [3H]sufentanil (mu selective), [3H][D-Pen2,D-Pen5]enkephalin (delta selective), and [3H]U69,593 (kappa selective) were established in membranes from rat brain cerebrum, monkey cortex, or guinea pig cerebellum. The selectivity index of various opioid alkaloids and peptides in binding to the mu, delta, or kappa opioid receptors was expressed as the ratio of their EC50 values in displacing two selective radiolabeled ligands: [3H]sufentanil/[3H](D-Pen2,D-Pen5)enkephalin (selectivity: mu/delta), [3H]sufentanil/[3H]U69,593 (selectivity: mu/kappa), or [3H][D-Pen2,D-Pen5]enkephalin/[3H]U69,593 (selectivity: delta/kappa). High resolution in binding selectivity was observed: in rat brain the mu/delta selectivity for Tyr-D-Ala-Gly-(Me)Phe-Gly-ol and sufentanil were 0.02 and 0.03, whereas for [D-Pen2,D-Pen5]enkephalin and ICI 174,864 they were 1,200 and 998. Compared to mu opiates, the specific binding of delta and kappa agonists was less sensitive to sodium. The results describe a routinely applicable methodological approach for the assessment of selective ligand binding to the mu, delta and kappa opioid receptors in rodent and monkey brain membranes.

Activation of G protein by opioid receptors: role of receptor number and G-protein concentration.

The collision-coupling model for receptor-G-protein interaction predicts that the rate of G-protein activation is dependent on receptor density, but not G-protein levels. C6 cells expressing mu- or delta-opioid receptors, or SH-SY5Y cells, were treated with beta-funaltrexamine (mu) or naltrindole-5'-isothiocyanate (delta) to decrease receptor number. The time course of full or partial agonist-stimulated ¿35SGTPgammaS binding did not vary in C6 cell membranes containing <1-25 pmol/mg mu-opioid receptor, or 1. 4-4.3 pmol/mg delta-opioid receptor, or in SHSY5Y cells containing 0. 16-0.39 pmol/mg receptor. The association of ¿35SGTPgammaS binding was faster in membranes from C6mu cells than from C6delta cells. A 10-fold reduction in functional G-protein, following pertussis toxin treatment, lowered the maximal level of ¿35SGTPgammaS binding but not the association rate. These data indicate a compartmentalization of opioid receptors and G protein at the cell membrane.