Sodium-glucose cotransporter 2 (SGLT-2) inhibitors and microvascular outcomes in patients with type 2 diabetes: systematic review and meta-analysis.

PURPOSE: The effect of the sodium-glucose 2 (SGLT-2) inhibitors on microvascular complications remains uncertain. We performed a systematic review to determine the efficacy of the SGLT-2 inhibitors on microvascular outcomes in patients with type 2 diabetes. METHODS: A comprehensive search was performed using Ovid, MEDLINE, EMBASE, Web of Science, and Scopus from inception to May 2019. Randomized trials comparing SGLT-2 inhibitors with placebo or other medication for type 2 diabetes for ≥ 4 weeks were included. Diabetes-related microvascular complications such as nephropathy, retinopathy, neuropathy, and peripheral vascular disease were evaluated. A random-effect model using mean differences for continuous outcomes and risk ratio for dichotomous outcomes was used to synthesize data. PROSPERO (CRD 42017076460). RESULTS: A total of 40 RCTs with overall moderate quality of evidence were included. SGLT-2 inhibitors reduced the risk of renal-replacement therapy (0.65; 95% CI 0.54-0.79), renal death (0.57; 95% CI 0.49-0.65), and progression of albuminuria (0.69; 95% CI 0.66-0.73). Conversely, they appeared ineffective in maintaining eGFR (0.33; 95% CI - 0.74 to 1.41) or reducing serum creatinine (- 0.07; 95% CI - 0.26 to 0.11), whereas urine albumin-creatinine ratio (- 23.4; 95% CI - 44.6 to - 2.2) was reduced. Risk of amputation was non-significant (1.30; 95% CI 0.93-1.83). No available data were found regarding neuropathy and retinopathy to perform a quantitative analysis. CONCLUSION: SGLT-2 inhibitors may reduce the risk of renal patient-important outcomes but fail to improve surrogate outcomes. Apparently, no increased risk of amputations was observed with these medications. No data were available regarding other microvascular complications.

Dutogliptin, a selective DPP4 inhibitor, improves glycaemic control in patients with type 2 diabetes: a 12-week, double-blind, randomized, placebo-controlled, multicentre trial.

AIM: To determine efficacy and tolerability of dutogliptin, a dipeptidyl peptidase 4 (DPP4) inhibitor, in patients with type 2 diabetes mellitus. METHODS: This was a 12-week, multicentre, randomized, double-blind, placebo-controlled trial in 423 patients with type 2 diabetes with suboptimal metabolic control. Following a 2-week single-blind placebo run-in, patients aged 18-75 years with a body mass index of 25-48 kg/m(2) and baseline HbA1c of 7.3-11.0% were randomized 2:2:1 to receive once-daily oral therapy with either dutogliptin (400 or 200 mg) or placebo on a background medication of either metformin alone, a thiazolidinedione (TZD) alone or a combination of metformin plus a TZD. RESULTS: Average HbA1c at baseline was 8.4%. Administration of dutogliptin 400 and 200 mg for 12 weeks decreased HbA1c by -0.52% (p < 0.001) and -0.35% (p = 0.006), respectively (placebo-corrected values), with absolute changes in HbA1c for the 400 mg, 200 mg and placebo groups of -0.82, -0.64 and -0.3%, respectively. The proportion of patients achieving an HbA1c < 7% was 27, 21 and 12% at dutogliptin doses of 400 and 200 mg or placebo, respectively (p = 0.008 for comparison of 400 mg vs. placebo). Fasting plasma glucose (FPG) levels were significantly reduced in both active treatment groups compared to placebo: the placebo-corrected difference was -1.00 mmol/l (p < 0.001) for the 400 mg group and -0.88 mmol/l (p = 0.003) for the 200 mg group. Dutogliptin caused significantly greater reductions in postprandial glucose AUC (0-2h) in both the 400 and 200 mg groups (placebo corrected values -2.58 mmol/l/h, p < 0.001 and -1.63 mmol/l/h, p = 0.032, respectively). In general, patients tolerated the study drug well. There were minor, not clinically meaningful differences in adverse events (AEs) between dutogliptin-treated patients and placebo controls, and 60% of all reported AEs were mild. Vital signs and body weight were stable, and routine safety laboratory parameters did not change compared with placebo. Trough ex vivo DPP4 inhibition at the end of the 12-week treatment period was 80 and 70%, at the 400 and 200 mg doses of dutogliptin, respectively. CONCLUSIONS: Dutogliptin treatment for 12 weeks improved glycaemic control in patients with type 2 diabetes who were on a background medication of metformin, a TZD or metformin plus a TZD. Tolerability was favourable for both doses tested. The 400 mg dose of dutogliptin resulted in larger changes of HbA1c and FPG and more subjects reached an HbA1c target of < 7% than the 200 mg dose.

The dipeptidyl peptidase-4 inhibitor PHX1149 improves blood glucose control in patients with type 2 diabetes mellitus.

AIM: To determine the efficacy and tolerability of PHX1149, a novel dipeptidyl peptidase-4 (DPP4) inhibitor, in patients with type 2 diabetes. METHODS: This is a multicentre, randomized, double-blind, placebo-controlled, 4-week study in patients with type 2 diabetes with suboptimal metabolic control. Patients with a baseline haemoglobin A(1c) (HbA(1c)) of 7.3 to 11.0% were randomized 1 : 1 : 1 : 1 to receive once-daily oral therapy with either PHX1149 (100, 200 or 400 mg) or placebo; patients were on a constant background therapy of either metformin alone or metformin plus a glitazone. RESULTS: Treatment with 100, 200 or 400 mg of PHX1149 significantly decreased postprandial glucose area under the curve AUC(0-2 h) by approximately 20% (+0.11 +/- 0.50, -2.08 +/- 0.51, -1.73 +/- 0.49 and -1.88 +/- 0.48 mmol/l x h, respectively, for placebo and 100, 200 and 400 mg (p = 0.002, 0.008 and 0.004 vs. placebo). Postprandial AUC(0-2 h) of intact glucagon-like peptide-1, the principal mediator of the biological effects of DPP4 inhibitors, was increased by 3.90 +/- 2.83, 11.63 +/- 2.86, 16.42 +/- 2.72 and 15.75 +/- 2.71 pmol/l x h, respectively, for placebo and 100, 200 and 400 mg (p = 0.053, 0.001 and 0.002 vs. placebo). Mean HbA(1c) was lower in all dose groups; the placebo-corrected change in the groups receiving 400 mg PHX1149 was -0.28% (p = 0.02). DPP4 inhibition on day 28 was 53, 73 and 78% at 24 h postdose in the groups receiving 100, 200 and 400 mg PHX1149, respectively. There were no differences in adverse events between PHX1149-treated and placebo subjects. CONCLUSIONS: Addition of the DPP4 inhibitor PHX1149 to a stable regimen of metformin or metformin plus a glitazone in patients with type 2 diabetes was well tolerated and improved blood glucose control.

FLT3 K663Q is a novel AML-associated oncogenic kinase: Determination of biochemical properties and sensitivity to Sunitinib (SU11248).

Somatic mutations of FLT3 resulting in constitutive kinase activation are the most common acquired genomic abnormality found in acute myeloid leukemia (AML). The majority of these mutations are internal tandem duplications (ITD) of the juxtamembrane region (JM). In addition, a minority of cases of AML are associated with mutation of the FLT3 activation loop (AL), typically involving codons D835 and/or I836. We hypothesized that other novel mutations of FLT3 could also contribute to leukemogenesis. We genotyped 109 cases of AML and identified two novel gain-of-function mutations. The first mutation, N841 H, is similar to previously described mutations involving amino-acid substitutions of codon 841. The other novel mutation, FLT3 K663Q, is the first AML-associated gain-of-function mutation located outside the JM and AL domains. Of note, this mutation was potently inhibited by Sunitinib (SU11248), a previously described FLT3 kinase inhibitor. Sunitinib reduced the proliferation and induced apoptosis of transformed Ba/F3 cells expressing FLT3 K663Q. The potency of Sunitinib against FLT3 K663Q was similar to its potency against FLT3 ITD mutations. We conclude that FLT3 mutations in AML can involve novel regions of the TK1. Future studies are needed to define the incidence and prognostic significance of FLT3 mutations outside the well-established JM and AL regions.

Systematic review with meta-analysis: recurrence of Crohn's disease after total colectomy with permanent ileostomy.

BACKGROUND: Subtotal or total colectomy or proctocolectomy with permanent ileostomy (TC-PI) may be a treatment option for medically refractory colonic Crohn's disease (CD). AIM: To perform a systematic review and meta-analysis to evaluate the rate, risk factors and outcomes of CD recurrence after TC-PI. METHODS: In a systematic review ending 31 March 2016, we identified 18 cohort studies (1438 adults) who underwent TC-PI for colonic CD (median follow-up, 7.4 years; interquartile range, 5.3-9.0). We estimated pooled rates [with 95% confidence interval (CI)] of clinical and surgical recurrence, and risk factors for disease recurrence. RESULTS: On meta-analysis, the risk of clinical recurrence after TC-PI was 28.0% (95% CI, 21.7-35.3; 14 studies, 260/1004 patients), with a 5 and 10-year median cumulative rate of 23.5% (range, 7-35) and 40% (range, 11-60) respectively. The risk of surgical recurrence was 16.0% (95% CI, 11.1-22.7; 10 studies; 183/1092 patients), with a 5 and 10-year median cumulative rate of 10% (range, 3-29) and 18.5% (range, 14-34) respectively. The risk of clinical and surgical recurrence in patients without ileal disease at baseline was 11.5% (95% CI, 7.7-16.8) and 10.4% (95% CI, 4.5-22.5) respectively. History of ileal disease was associated with 3.2 times higher risk of disease recurrence (RR, 3.2; 95% CI, 1.8-5.6). Other inconsistent risk factors for disease recurrence were penetrating disease and young age at disease onset. CONCLUSIONS: Small bowel clinical recurrence occurs in about 28% of patients after total colectomy with permanent ileostomy for colonic Crohn's disease. Disease recurrence risk is 3.2 times higher in patients with history of ileal disease, and continued medical therapy may be advisable in this population. In patients without ileal inflammation at surgery, continued endoscopic surveillance may identify asymptomatic disease recurrence to guide therapy.

Interleukin-3, granulocyte-macrophage colony-stimulating factor, and interleukin-5 transduce signals through two forms of STAT5.

Recently, JAK2 kinase was found to be one of the tyrosine kinases activated by interleukin-3 (IL-3) in target cells. JAK2 belongs to a family of kinases that act upstream of transcription factors called STATs. STATs exist in the cytoplasm as latent, transcriptionally inactive forms until, in response to extracellular signals, they become phosphorylated on tyrosine residues, translocate to the nucleus, and bind to specific DNA elements. Because IL-3 activates JAK2, we searched for the STAT(s) that might transduce IL-3 signals. Several lines of evidence suggest that IL-3 uses the murine homologue of STAT5, a factor originally purified from sheep. Unexpectedly, during isolation of the murine homologue, we found two highly related molecules that we have designated STAT5A and STAT5B.

Selective inhibition of primitive hemopoietic colony-forming cells by an extract from normal marrow: comparison with transforming growth factor-beta.

An extract from normal bone marrow (NBME) which inhibits proliferation of spleen colony-forming units CFU-S selectively inhibits interleukin 3 (IL-3)-driven colony formation by primitive hemopoietic progenitors. This activity is distinct from transforming growth factor-beta (TGF beta), which also inhibits development of primitive progenitors. There is evidence that the two activities inhibit proliferation of target cells by different mechanisms and that the bone marrow extract has a direct effect on cell cycling, whereas the effect of TGF beta to suppress proliferation is probably indirect.

Systematic review with meta-analysis: faecal diversion for management of perianal Crohn's disease.

BACKGROUND: Temporary faecal diversion is sometimes used for management of refractory perianal Crohn's disease (CD) with variable success. AIMS: To perform a systematic review with meta-analysis to evaluate the effectiveness, long-term outcomes and factors associated with success of temporary faecal diversion for perianal CD. METHODS: Through a systematic literature review through 15 July 2015, we identified 16 cohort studies (556 patients) reporting outcomes after temporary faecal diversion. We estimated pooled rates [with 95% confidence interval (CI)] of early clinical response, attempted and successful restoration of bowel continuity after temporary faecal diversion (without symptomatic relapse), and rates of re-diversion (in patients with attempted restoration) and proctectomy (with or without colectomy and end-ileostomy). We identified factors associated with successful restoration of bowel continuity. RESULTS: On meta-analysis, 63.8% (95% CI: 54.1-72.5) of patients had early clinical response after faecal diversion for refractory perianal CD. Restoration of bowel continuity was attempted in 34.5% (95% CI: 27.0-42.8) of patients, and was successful in only 16.6% (95% CI: 11.8-22.9). Of those in whom restoration was attempted, 26.5% (95% CI: 14.1-44.2) required re-diversion because of severe relapse. Overall, 41.6% (95% CI: 32.6-51.2) of patients required proctectomy after failure of temporary faecal diversion. There was no difference in the successful restoration of bowel continuity after temporary faecal diversion in the pre-biological or biological era (13.7% vs. 17.6%, P = 0.60), in part due to selection bias. Absence of rectal involvement was the most consistent factor associated with restoration of bowel continuity. CONCLUSIONS: Temporary faecal diversion may improve symptoms in approximately two-thirds of patients with refractory perianal Crohn's disease, but bowel restoration is successful in only 17% of patients.

Regulation of HMG-CoA synthase and HMG-CoA reductase by insulin and epidermal growth factor in HaCaT keratinocytes.

Synthesis of cholesterol, via the isoprenoid/mevalonate pathway, is required for keratinocyte growth and differentiation, and maintenance of the stratum corneum lipid lamellae. 3-hydroxy-3-methylglutaryl coenzyme A synthase catalyzes the first step in isoprenoid/mevalonate synthesis and under some conditions controls the flux into the pathway. We have investigated whether selected growth factors and hormones could increase 3-hydroxy-3-methylglutaryl coenzyme A synthase mRNA in keratinocytes. Northern blotting was used to demonstrate that 10 microg per ml insulin and 0.1 microg per ml epidermal growth factor both increased steady-state levels of 3-hydroxy-3-methylglutaryl coenzyme A synthase mRNA by 2.5 and 6-fold, respectively. Epidermal growth factor and insulin also increased 3-hydroxy-3-methylglutaryl coenzyme A reductase enzyme activity. 3-hydroxy-3-methylglutaryl coenzyme A synthase promoter activity in a luciferase reporter construct was increased 2-fold by insulin and 2.9-fold by epidermal growth factor. When a mutation in the sterol regulatory element was introduced into the 3-hydroxy-3-methylglutaryl coenzyme A synthase promoter, activity was not increased by insulin, but was increased by epidermal growth factor. Mutation of an AP-1 site in the 3-hydroxy-3-methylglutaryl coenzyme A synthase promoter did not affect the increase in activity following treatment with insulin or epidermal growth factor. Therefore, 3-hydroxy-3-methylglutaryl coenzyme A synthase expression in keratinocytes is regulated by insulin and epidermal growth factor by different mechanisms. These results suggest a role for hormones and growth factors in the control of epidermal cholesterol synthesis.

Expression and regulation of mRNA for putative fatty acid transport related proteins and fatty acyl CoA synthase in murine epidermis and cultured human keratinocytes.

The epidermis has a requirement for fatty acids in order to synthesize cellular membranes and the extracellular lipid lamellar membranes in the stratum corneum. Despite high endogenous production of fatty acids the transport of exogenous essential fatty acids into the epidermis is an absolute requirement. Fatty acid uptake by keratinocytes has been shown to be mediated by a transport system. In this study we determined in murine epidermis and human cultured keratinocytes the expression of three putative fatty acid transport related proteins and fatty acyl CoA synthase, an enzyme that facilitates the uptake of fatty acids by promoting their metabolism. In cultured human keratinocytes, mRNA for fatty acid transport protein (FATP), plasma membrane fatty acid binding protein (FABP-pm), and fatty acyl CoA synthase (FACS) were detectable. Differentiation, induced by high calcium, did not affect FATP mRNA levels, but resulted in an approximately 50% increase in FACS mRNA, while decreasing FABP-pm mRNA by 50%. Fatty acid translocase (FAT) mRNA was not detected in cultured human keratinocytes. In murine epidermis, FATP, FABP-pm, FACS, and FAT mRNA were all present. Barrier disruption by either tape stripping or acetone treatment increased FAT mRNA levels by approximately 2-fold without affecting FATP, FABP-pm, or FACS. Occlusion with an impermeable membrane immediately after barrier disruption completely blocked the increase in FAT mRNA levels, indicating that this increase is related to barrier disruption rather than a nonspecific injury effect. In summary, this study demonstrates that several putative fatty acid transport related proteins as well as fatty acyl CoA synthase are expressed in keratinocytes and epidermis, and that the expression of these proteins may be regulated by differentiation and/ or barrier disruption.

Permeability barrier disruption coordinately regulates mRNA levels for key enzymes of cholesterol, fatty acid, and ceramide synthesis in the epidermis.

The extracellular lipids of the stratum corneum, which are comprised mainly of cholesterol, fatty acids, and ceramides, are essential for epidermal permeability barrier function. Moreover, disruption of the permeability barrier results in an increased cholesterol, fatty acid, and ceramide synthesis in the underlying epidermis. This increase in lipid synthesis has been shown previously to be due to increased activities of HMG-CoA reductase, acetyl-CoA carboxylase, fatty acid synthase and serine palmitoyl transferase, key enzymes of cholesterol, fatty acid, and ceramide synthesis, respectively. In the present study, we determined whether the mRNA levels for the key enzymes required for synthesis of these three classes of lipids increase coordinately during barrier recovery. By northern blotting, the steady-state mRNA levels for HMG-CoA reductase, HMG-CoA synthase, farnesyl pyrophosphate synthase, and squalene synthase, key enzymes for cholesterol synthesis, all increased significantly after barrier disruption by either acetone or tape stripping. Additionally, the steady-state mRNA levels of acetyl-CoA carboxylase and fatty acid synthase, required for fatty acid synthesis, as well as serine palmitoyl transferase, the rate-limiting enzyme of de novo ceramide synthesis, also increased. Furthermore, artificial restoration of the permeability barrier by occlusion after barrier disruption prevented the increase in mRNA levels for all of these enzymes, except farnesyl pyrophosphate synthase, indicating a specific link of the increase in mRNA levels to barrier requirements. The parallel increase in epidermal mRNA levels for the enzymes required for cholesterol, fatty acid, and ceramide synthesis may be due to one or more transcription factors that regulate lipid requirements for permeability barrier function in keratinocytes.

Optical intrinsic signal imaging in a rodent seizure model.

The authors studied seizure activity with optical intrinsic signal (OIS) imaging in a rat seizure model. OIS, which measures vascular and metabolic effects associated with neuronal activity, showed significant cortical reflectance changes from penicillin-induced seizures, and correlated well with EEG epileptiform discharges. Furthermore, OIS changes often preceded initial EEG spikes. These observations suggest that OIS is well coupled with seizure activity, and may provide sensitive cues for seizure detection.

Purinoceptor activation of chloride transport in cystic fibrosis and CFTR-transfected pancreatic cell lines.

The regulation of chloride efflux from cystic fibrosis pancreatic adenocarcinoma cells (CFPAC-1) and wild-type CFTR-transfected CFPAC-1 cells (TPAC) was compared. Forskolin (10 microM) stimulated chloride efflux from the corrected TPAC cells but not from CFPAC-1 cells. Chloride efflux from both cell types was activated by thapsigargin (0.5 microM). The nucleotides ATP and UTP and the non-hydrolyzable ATP analogue, adenosine 5'-O-(3-thio) triphosphate (ATPgammaS), stimulated chloride efflux from both cell types. None of the other P2 purinoceptor agonists investigated elicited a response. The order of potency was ATP > or = UTP > or = ATPgammaS. Adenosine (10-100 microM) activated choride efflux from the TPAC but not the CFPAC cell line with no increase in intracellular cyclic AMP. Small but statistically significant inhibitions of the adenosine-(50 microM)-stimulated increase in chloride efflux were elicited by the A1 receptor antagonist 8-cyclopentyl-1,3-dipropylxanthine (CPX, 100 nM) and the A2 receptor antagonist 3,7-dimethyl-1-propylargylxanthine (DMPX, 10 microM). The A2A receptor antagonist 8-(3-chlorostyryl)caffeine (CSC, 100 nM) had no significant effect. These results provide evidence for the regulation of chloride efflux by P2Y2 purinoceptors in genetically-corrected and CF pancreatic cell lines. Studies with adenosine receptor antagonists indicate some possible involvement of A1 and A2 (but not A2A) receptors in the adenosine stimulation of chloride efflux, but the relatively small effects of the inhibitors coupled with lack of increase in cyclic AMP and a response only in the CFTR-transfected cells also suggests a possible direct effect of adenosine on CFTR.

Complement activation by cellulosic dialysis membranes.

AIMS: To assess the effect of cellulosic dialysis membranes on the production of complement degradation products to determine to the role of the classical pathway. METHOD: Complement activation was studied in 33 patients during a single haemodialysis session using cellulosic membranes. Pre- and post-dialysis plasma EDTA valves of C3, C4, C3dg, C4d and C reactive protein (CRP) were measured. Statistical analysis was done using the Wilcoxon signed rank test. RESULTS: Post-dialysis C4 (p = 0.0003), C3dg (p < 0.0001), and C4d (p = 0.003) concentrations were increased compared with pre-dialysis values. There was no significant change in C3 (p = 0.095) and CRP (p = 0.13) values. Post-dialysis C3dg and C4d concentrations correlated significantly (p = 0.007). IgG, an undialysed molecule, was quantified and post-dialysis valves were significantly higher than those before dialysis (p = 0.0002), indicating a degree of haemoconcentration. To remove this effect, the C3:IgG, C4:IgG, C3dg:IgG, C4d:IgG and CRP:IgG ratios were calculated. Compared with pre-dialysis values, post-dialysis C3dg:IgG and C4d:IgG ratios were increased and C3:IgG decreased significantly. No change was observed in C4:IgG and CRP:IgG ratios. CONCLUSION: This study confirms that significant complement activation takes place following dialysis with cellulosic membranes. This is denoted by an increase in C3dg. This was paralleled by a rise in C4d, implying a contributory role for the classical pathway. Concomitant post-dialysis increases in IgG and C4 indicate a degree of haemoconcentration; but removal of this effect shows that C3dg and C4d are increased following dialysis--suggesting classical, in addition to alternative, pathway activation.

Characterization of optical intrinsic signals and blood volume during cortical spreading depression.

Cortical spreading depression (CSD) was imaged in vivo in a rodent model with optical intrinsic signals (OIS). This is the first study to identify a triphasic OIS response and to characterize the rate and timing of the response. The initial OIS phase had a highly uniform wavefront, which spread at a rate characteristic of CSD, 3.5 mm/min. Later phases were more diffuse and inhomogeneous. Blood volume changes, measured with intravascular fluorescent dye, correlated in time and location with the later phases of OIS response. This suggests that the inhomogeneity of the late OIS response may be due to complex residual hemodynamic contributions, as opposed to underlying cortical circuitry.

Cloning, nucleotide sequence determination and expression of the Staphylococcus aureus hyaluronate lyase gene.

The Staphylococcus aureus 8325-4 hyaluronate lyase gene (hysA) was identified after detecting hyaluronate lyase activity expressed by phages from a genomic library. The hysA open reading frame, capable of encoding a protein of 91 980 Da, was identified by Tn5 mutagenesis and nucleotide sequencing. HysA shares 35 and 36% amino acid sequence identity with group B streptococcal hyaluronate lyase and pneumococcal hyaluronidase, respectively. A 94-kDa protein was expressed in Escherichia coli minicells, a result consistent with the coding capacity of hysA. Identification of the S. aureus 8325-4 hyaluronate lyase gene will allow the regulation of this putative virulence determinant to be studied.

Parainfluenza virus type 3 induced alterations in tachykinin NK1 receptors, substance P levels and respiratory functions in guinea pig airways.

We have investigated the effects of parainfluenza virus type 3 (PI-3) on sensory neuropeptide levels, tachykinin receptors and their functions in guinea pig airways during the course of respiratory viral infection. PI-3 infected guinea pigs were hyperresponsive to methacholine and substance P aerosols as determined by earlier onset of dyspnea in these animals as compared with control on post-inoculation day (PID) 7 but not 19. In addition, plasma protein extravasation produced in response to the tachykinin was increased in infected airways during the first week post inoculation. Infected guinea pig trachea did not respond any differently to methacholine when smooth muscle contraction and [3H]inositol phosphate accumulation were measured although the magnitude of substance P effects using in vitro tests was significantly greater than control on post-inoculation day 7 but not 19. Trachea from PI-3 infected animals were characterized by reductions in substance P-like immunoreactivity, tachykinin NK1 receptor number and agonist affinity during the first post-inoculation week. Substance P levels or tachykinin NK1 receptor numbers or affinity were not altered in trachea of guinea pigs 4 days after treatment with lipopolysaccharide. These data suggest substance P release occurs during critical periods of respiratory viral infection which are temporally correlated with airway hyperresponsiveness. Despite apparent down-regulation of tachykinin NK1 receptors, substance P-mediated functions remained enhanced suggesting some alterations in post-receptor mechanisms.

Tachykinin-mediated respiratory effects in conscious guinea pigs: modulation by NK1 and NK2 receptor antagonists.

Tachykinins, in particular neurokinin A and substance P, produce a number of airway effects which may contribute to respiratory diseases such as asthma. We examined the ability of aerosolized substance P, neurokinin A or capsaicin to produce respiratory alterations in conscious guinea pigs using modified whole body plethysmography. Substance P-mediated dyspnea and significant respiratory events were inhibited by the NK1 receptor antagonist, CP-96,345. Neurokinin A-mediated respiratory effects were ablated by the NK2 receptor antagonists: MEN 10207, MDL 29,913 and SR 48,968, the latter being the most potent. The peptide-based antagonist, MEN 10207, produced respiratory effects itself suggesting partial agonist activity. The cyclic hexapeptide, MDL 29,913, relaxed airway smooth muscle via mechanisms other than tachykinin antagonism. NK2 but not NK1 receptor antagonists were able to delay the onset of capsaicin-induced dyspnea, although alone they did not usually (in approximately 10% of the animals) eliminate the response. However, when NK2 receptor antagonists were combined with CP-96,345, the incidence of dyspnea induced by capsaicin decreased significantly (40%) suggesting that both tachykinins contribute to dyspnea in this system.

Optical imaging of bilingual cortical representations. Case report.

The organization of language in the brains of multilingual persons remains controversial. The authors investigated language representations in a proficient bilingual patient by using a novel neuroimaging technique, intraoperative optical imaging of intrinsic signals (iOIS), and a visual object naming task. The results indicate that there are cortical areas that are activated by the use of both English and Spanish languages (superior temporal sulcus, superior and middle temporal gyri, and parts of the supramarginal gyrus). In addition, language-specific areas were identified in the supramarginal (Spanish) and precentral (English) gyri. These results suggest that cortical language representations in bilingual persons may consist of both overlapping and distinct components. Furthermore, this study demonstrates the utility of iOIS in detecting topographical segregation of cognitively distinct cortices.

Inhibition of 5-lipoxygenase by substituted 3,4-dihydro-2H-1,4-thiazines.

A series of substituted 3,4-dihydro-2H-1,4-thiazines inhibit 5-lipoxygenase from rat leukocytes and exhibit submicromolar IC50 values. A novel synthesis of these compounds was developed based on the formation of hydroxymethyleneamine 13 and its cyclization to the title compounds. The dihydrothiazines have low oxidation potentials, typically E1/2 is near 0.3 V, and a representative compound reduces Fe(III)(phen)3, with k = 10(5) M-1s-1. We propose that these lipophilic compounds bind to 5-lipoxygenase and reduce the iron in the active site, thus inactivating the enzyme.