CircHIPK2 facilitates phenotypic switching of vascular smooth muscle cells in hypertension

Hypertension is a clinical syndrome characterized by increased systemic arterial blood pressure, affecting about 1.4 billion people currently worldwide with only one in seven cases adequately controlled. It is the main contributing factor of cardiovascular diseases (CVDs), often co-existing with other CVDs risk factors to impair the structure and function of important organs such as heart, brain, and kidney, and ultimately lead to multi-organ failure. Vascular remodeling is a critical process in the development of essential hypertension, and phenotype switching of vascular smooth muscle cells (VSMCs) was reported contributing substantially to vascular remodeling. circHIPK2 is a circular RNA (circRNA) derived from the second exon of homeodomain-interacting protein kinase 2 (HIPK2). Several studies revealed that circHIPK2 functions in various diseases by serving as a microRNA (miRNA) sponge. However, the functional roles and molecular mechanisms of circHIPK2 in VSMC phenotype switching and hypertension are not clear. In the present study, we showed that the expression of circHIPK2 was significantly upregulated in the VSMCs of hypertensive patients. Functional studies showed that circHIPK2 promoted the Angiotensin II (AngII)-induced VSMC phenotype switching by acting as the sponge of miR-145-5p, thereby upregulating the expression of a disintegrin and metalloprotease (ADAM) 17. Collectively, our study provides a new therapeutic target for hypertension.

Regulatory roles of external cholesterol in human airway epithelial mitochondrial function through STARD3 signalling

BACKGROUND

Hypercholesterolemia is found in patients with chronic lung inflammation, during which airway epithelial cells play important roles in maintenance of inflammatory responses to pathogens. The present study aims at molecular mechanisms by which cholesterol changes airway epithelial sensitivity in response to smoking.

METHODS

Human bronchial epithelial cells (HBEs) were stimulated with cigarette smoke extract (CSE) and mice were exposed to CS/lipopolysaccharide (LPS) as models in vitro and in vivo. Severe COPD patients and healthy volunteers were also enrolled and the level of cholesterol in plasma was detected by metabolomics. Filipin III and elisa kits were used to stain free cholesterol. Mitochondrial function was detected by mitotracker green, mitotracker green, and Seahorse. Mitochondrial morphology was detected by high content screening and electron microscopy. The mRNA and protein levels of mitochondrial dynamics-related proteins were detected by RT-qPCR and Western blot,respectively. BODIPY 493/503 was used to stain lipid droplets. Lipidomics was used to detect intracellular lipid components. The mRNA level of interleukin (IL)-6 and IL-8 were detected by RT-qPCR.

RESULTS

We found that the cholesterol overload was associated with chronic obstructive pulmonary disease (COPD) and airway epithelia-driven inflammation, evidenced by hypercholesterolemia in patients with COPD and preclinical models, alteration of lipid metabolism-associated genes in CSE-induced airway epithelia and production of ILs. External cholesterol altered airway epithelial sensitivity of inflammation in response to CSE, through the regulation of STARD3-MFN2 pathway, cholesterol re-distribution, altered transport and accumulation of cholesterol, activities of lipid transport regulators and disorder of mitochondrial function and dynamics. MFN2 down-regulation increased airway epithelial sensitivity and production of ILs after smoking, at least partially by injuring fatty acid oxidation and activating mTOR phosphorylation.

CONCLUSIONS

Our data provide new insights for understanding molecular mechanisms of cholesterol-altered airway epithelial inflammation and for developing diagnostic biomarkers and therapeutic targets to improve patient outcomes.

Efficacy and safety of maralixibat treatment in patients with Alagille syndrome and cholestatic pruritus (ICONIC): a randomised phase 2 study

BACKGROUND

Alagille syndrome is a rare genetic disease that often presents with severe cholestasis and pruritus. There are no approved drugs for management. Maralixibat, an apical, sodium-dependent, bile acid transport inhibitor, prevents enterohepatic bile acid recirculation. We evaluated the safety and efficacy of maralixibat for children with cholestasis in Alagille syndrome.

METHODS

ICONIC was a placebo-controlled, randomised withdrawal period (RWD), phase 2b study with open-label extension in children (aged 1-18 years) with Alagille syndrome (NCT02160782). Eligible participants had more than three times the normal serum bile acid (sBA) levels and intractable pruritus. After 18 weeks of maralixibat 380 μg/kg once per day, participants were randomly assigned (1:1) to continue maralixibat or receive placebo for 4 weeks. Subsequently, all participants received open-label maralixibat until week 48. During the long-term extension (204 weeks reported), doses were increased up to 380 μg/kg twice per day. The primary endpoint was the mean sBA change during the RWD in participants with at least 50% sBA reduction by week 18. Cholestastic pruritus was assessed using observer-rated, patient-rated, and clinician-rated 0-4 scales. The safety population was defined as all participants who had received at least one dose of maralixibat. This trial was registered with ClinicalTrials.gov, NCT02160782, and is closed to recruitment.

FINDINGS

Between Oct 28, 2014, and Aug 14, 2015, 31 participants (mean age 5·4 years [SD 4·25]) were enrolled and 28 analysed at week 48. Of the 29 participants who entered the randomised drug withdrawal period, ten (34%) were female and 19 (66%) were male. In the RWD, participants switched to placebo had significant increases in sBA (94 μmol/L, 95% CI 23 to 164) and pruritus (1·7 points, 95% CI 1·2 to 2·2), whereas participants who continued maralixibat maintained treatment effect. This study met the primary endpoint (least square mean difference -117 μmol/L, 95% CI -232 to -2). From baseline to week 48, sBA (-96 μmol/L, -162 to -31) and pruritus (-1·6 pts, -2·1 to -1·1) improved. In participants who continued to week 204 (n=15) all improvements were maintained. Maralixibat was generally safe and well tolerated throughout. The most frequent adverse events were gastrointestinal related. Most adverse events were self-limiting in nature and mild-to-moderate in severity.

INTERPRETATION

In children with Alagille syndrome, maralixibat is, to our knowledge, the first agent to show durable and clinically meaningful improvements in cholestasis. Maralixibat might represent a new treatment paradigm for chronic cholestasis in Alagille syndrome.

FUNDING

Mirum Pharmaceuticals.

Overexpression of TRIM3 protects against LPS-induced acute kidney injury via repressing IRF3 pathway and NLRP3 inflammasome

PURPOSE

The pathological process of sepsis involves multiple system organs, including kidney. Sepsis-induced acute kidney injury (AKI) has high morbidity and high mortality. Overproduced inflammatory factors contribute to the occurrence and evolvement of AKI. Here, the role and underlying mechanism of tripartite motif containing 3 (TRIM3) and in AKI was explored.

METHODS

Lipopolysaccharide (LPS) was used for constructing AKI model both in vitro and in vivo. RT-PCR and western blot were performed to detect TRIM3, Interferon regulatory factor 3 (IRF3) and NLRP3-ASC-Caspase1 inflammasome. Upon selectively regulating the TRIM3 or IRF3 expression, the proliferation, apoptosis and inflammatory response were detected. The interaction between TRIM3 and IRF3 was verified by Immunoprecipitation (IP).

RESULTS

TRIM3 was down-regulated in mediated injury renal tubular epithelial cell line HK-2 treated with LPS. Overexpression of TRIM3 promoted cell viability and reduced apoptosis. In addition, overexpression of TRIM3 inhibited the expression of inflammatory factors (IL-1β, IL-6, TNF-α and IL-18), dampened the phosphorylation of IRF3 and repressed NLRP3 inflammasome activation. Furthermore, TRIM3 overexpression significantly eased the LPS-induced damage on AKI rat model and decreased the serum creatinine and urea nitrogen levels in rat kidney tissues. The results of immunohistochemistry (IHC) and Western blot manifested that TRIM3 was increased dramatically after TRIM3 was overexpressed in the rat kidney tissues, while IRF3 and NLRP3-ASC-Caspase1 inflammasome were significantly repressed following TRIM3 upregulation in the kidney tissues. Mechanistically, TRIM3 interacted with IRF3 and inhibited its phosphorylation.

CONCLUSION

Overexpression of TRIM3 protected against LPS-induced AKI by inhibiting the IRF3 pathway and NLRP3 inflammasome activation.

LTP allergy/sensitization in a pediatric population

Plant lipid transfer proteins (LTPs) are widespread plant food allergens, highly resistant to food processing and to the gastrointestinal environment, which have been described as the most common food allergens in the Mediterranean area. LTP allergy is widely described in adults, but it represents an emerging allergen also in the pediatric population. Little is known about the real prevalence and the clinical features of this allergy in children and it still often remains underdiagnosed in these patients. An early identification and a deeper knowledge of this allergy in childhood can avoid severe systemic reactions and improve the child's quality of life. Pediatricians should always consider the possibility of LTP involvement in cases of plant-derived food allergy.

Nickel allergy in lipid transfer protein sensitized patients: Prevalence and clinical features

Nickel (Ni), the main responsible for allergic contact dermatitis worldwide, is also involved in systemic condition called "Systemic Nickel Sulfate Allergy Syndrome (SNAS)." Likewise, IgE-mediated reactivity to Lipid Transfer Protein (LTP) represents the main cause of primary food allergy in adults of Mediterranean countries. We evaluated the prevalence of SNAS in LTP allergic patients and investigated patients' clinical features with double sensitization (LTP and Ni). A retrospective, single-center, observational study was conducted performing a complete allergological work-up including: (1) skin prick tests; (2) serum specific IgE for plant food allergens and rPru p3 (LTP); (3) patch test with 5% Ni sulfate in petrolatum. We enrolled 140 LTP allergic patients of which 36 patients (25.7% of sample) showed additional positivity to Ni patch test. Patients with double sensitization were more frequently females and reported fewer cutaneous symptoms. Higher values of sIgE for peach, apple, peanut, walnut, grain, corn, and garlic were found in LTP allergic patients, while higher values for hazelnut in the other subgroup. The prevalence of SNAS in the LTP allergic population is clinically relevant. Moreover, the clinical and immunological profiles of patients with double sensitization were different from patients monosensitized to LTP.

Food Allergies Caused by Allergenic Lipid Transfer Proteins: What Is behind the Geographic Restriction?

PURPOSE OF REVIEW

To critically examine evidence suggesting that food allergy induced by lipid transfer proteins (LTPs) follows a geographic pattern.

RECENT FINDINGS

LTP syndrome remains most common in the Mediterranean basin, with a clear gradient seen in prevalence of LTP sensitization between northern and southern Europe. We hypothesize that high levels of birch pollen seem to protect against LTP allergy, as these higher levels correlate with a lower prevalence of LTP hypersensitivity. Nevertheless, LTP food allergy cases still appear in areas having a high environmental level of birch pollen. Food allergy caused by LTP may be related to (1) primary sensitization to a food LTP allergen in the absence of pollinosis, (2) primary sensitization to LTP from a pollen source, and (3) co-sensitization to LTP from pollen and food.

A Potential New Risk Factor for Stroke: Streptococcus Mutans With Collagen-Binding Protein

BACKGROUND

Among human oral bacteria, particular kinds of Streptococcus mutans (SM) known as dental caries pathogens contain a collagen-binding protein, Cnm, and show platelet aggregation inhibition and matrix metalloproteinase-9 activation. We have previously reported that these strains may be a risk factor for intracerebral hemorrhage. As a major sample-providing hospital, we report the clinical details, including intracranial aneurysms and ischemic stroke.

METHODS

After the study received approval from the Ethical Committee, 429 samples of whole saliva were obtained from patients who were admitted to or visited our hospital between February 16, 2010, and February 28, 2011. The study cohort comprised 48 patients with cardioembolic stroke (CES), 151 with non-CES infarct, 54 with intracerebral hemorrhage (ICH), 43 with ruptured intracranial aneurysm (RIA), and 97 with unruptured intracranial aneurysm (UIA). Cultured SM was identified as Cnm-positive when the corresponding gene was positive. The results were compared with those from 79 healthy volunteers. Relationships between Cnm-positive SM and known risk factors, including hypertension, diabetes, hyperlipidemia, smoking, and alcohol consumption, were analyzed.

RESULTS

A statistically significant high Cnm-positive rate was observed in patients with CES, non-CES infarct, ICH, and RIA (P = 0.002, 0.039, 0.013, and 0.009, respectively). There were no relationships between Cnm-positive SM and known risk factors.

CONCLUSIONS

Specific types of oral SM can be a risk factor for cardioembolic infarct, intracerebral hemorrhage, and intracranial aneurysm rupture. Further study is needed.

Arteriovenous fistula patency in the 3 years following vonapanitase and placebo treatment

OBJECTIVE

This study explored the long-term outcomes of arteriovenous fistulas treated with vonapanitase (recombinant human elastase) at the time of surgical creation.

METHODS

This was a randomized, double-blind, placebo-controlled trial of 151 patients undergoing radiocephalic or brachiocephalic arteriovenous fistula creation who were randomized equally to placebo, vonapanitase 10 μg, or vonapanitase 30 μg. The results after 1 year of follow-up were previously reported. The current analysis occurred when the last patient treated was observed for 3 years. For the current analysis, the primary end point was primary patency; the secondary end points included secondary patency, use of the fistula for hemodialysis, and rate of procedures to restore or to maintain patency.

RESULTS

There was no significant difference in the risk of primary patency loss with vonapanitase 10 μg or 30 μg vs placebo. When seven initial patency loss events related to cephalic arch and central vein balloon angioplasty were excluded, the risk of patency loss was reduced with vonapanitase overall (hazard ratio [HR], 0.63; P = .049) and 30 μg (HR, 0.51; P = .03). In patients with radiocephalic fistulas (n = 67), the risks of primary and secondary patency loss were reduced with 30 μg (HR, 0.37 [P = .02] and 0.24 [P = .046], respectively). The rate of procedures to restore or to maintain fistula patency was reduced with 30 μg vs placebo (0.23 vs 0.72 procedure days/patient/year; P = .03) and also reduced in patients with radiocephalic fistulas with 30 μg vs placebo (0.17 vs 0.85 procedure days/patient/year; P = .048).

CONCLUSIONS

In this study, vonapanitase did not significantly improve primary patency in the primary analysis but did significantly improve primary patency in an analysis that excluded patency loss due to cephalic arch and central vein balloon angioplasty. In patients with radiocephalic fistulas, 30 μg significantly improved primary and secondary patency. Vonapanitase 30 μg decreased the rate of procedures to restore or to maintain patency in the analysis that included all patients and in the subset with radiocephalic fistulas.

Lettuce Allergy Is a Lipid Transfer Syndrome-Related Food Allergy With a High Risk of Severe Reactions

BACKGROUND AND OBJECTIVE

Lipid transfer protein (LTP) sensitization is the most common cause of food allergy in the Mediterranean area, with peach allergy acting as the primary sensitizer in most cases. Lettuce has been described as a common offending food in patients with LTP syndrome. The aim of the study was to investigate the frequency and clinical expression of LTP syndrome in a sample of lettuceallergic patients.

METHODS

We determined specific IgE to Pru p 3 and lettuce in a sample of 30 patients with a diagnosis of lettuce allergy. Symptoms elicited by other LTP-containing plant-derived foods and the presence of cofactors were assessed.

RESULTS

The clinical symptoms of lettuce allergy were frequently severe, with 18 of the 30 patients experiencing anaphylaxis. All the patients had allergic reactions to other plant foods. Cofactors were involved in the clinical reactions of 13 of the 30 patients. Sensitization to pollens was found in 90% of patients.

CONCLUSIONS

Lettuce allergy is found not as an isolated condition but in the context of LTP syndrome and it is characterized by severe reactions and frequent cofactor association.

Application of human type I pancreatic elastase (PRT-201) to the venous anastomosis of arteriovenous grafts in patients with chronic kidney disease

PURPOSE

To explore the safety and efficacy of PRT-201 applied to the outflow vein of a newly created arteriovenous graft (AVG).

METHODS

Randomized, double-blind, placebo-controlled, single-dose escalation study of PRT-201 (0.01 to 9 mg) applied to the graft-vein anastomosis and adjacent outflow vein immediately after AVG placement. The primary outcome measure was safety. The efficacy measures were intraoperative increases in outflow vein diameter and blood flow rate, primary unassisted patency, and secondary patency by dose groups (placebo, low, medium, high and All PRT-201).

RESULTS

A total of 89 patients were treated (28 placebo and 61 PRT-201). There were no significant differences in the proportion of placebo and PRT-201 patients reporting adverse events. Intraoperative outflow vein diameter increased 5% (p=0.14) in the placebo group compared with 13% (p=0.01), 15% (p=0.07) and 12% (p<0.001), in the low, medium and high groups, respectively. The comparison between the high and placebo groups was marginally statistically significant (p=0.06). The intraoperative blood flow did not change in the placebo group, and increased in the low, medium and high groups by 19% (p=0.34), 36% (p=0.09) and 46% (p=0.02), respectively. The low group had the longest primary unassisted and secondary patency and the fewest procedures to restore or maintain patency; however, the differences between groups were not statistically significant.

CONCLUSIONS

PRT-201 was well tolerated and increased AVG intraoperative outflow vein diameter and blood flow. Low dose tended to increase secondary patency and decrease the rate of procedures to restore or maintain patency. Larger studies with these doses will be necessary to confirm these results.

Similarity of Insulin Detemir Pharmacokinetics, Safety, and Tolerability Profiles in Healthy Caucasian and Japanese American Subjects

The objective of this study was to compare the pharmacokinetics of insulin detemir in three ascending doses in healthy Japanese and Caucasian subjects. This was an open-label, single-center, parallel-group design evaluating 30 subjects (15 Japanese and 15 Caucasians). Subjects received a total of three subcutaneous injections (one injection per visit) of insulin detemir (0.19, 0.38, 0.75 U/kg [1 U = 24 nmol]) in ascending order. Following drug administration, subjects received intravenous glucose in 0.5-mg/kg/min increments every 30 minutes, followed by a constant rate of 2.0 mg/kg/min for up to 12 hours. For pharmacokinetic evaluations, serial blood sampling was performed over a period of 30 hours after dosing. Of the subjects, 36 were enrolled, and 30 completed the study. There was a linear dose-response relationship between the three ascending insulin detemir doses and serum insulin detemir AUC values for both the Japanese and Caucasian subjects. The two dose-response regression lines had equivalent slopes but slightly different intercepts (although not statistically significant). This difference may be due to variation in AUC, body weight differences, or chance. Six subjects discontinued the study, 2 as a result of adverse events (blood draw-related ecchymosis and hypoglycemia). The most frequent treatment-emergent adverse events (TEAE) were headache, dizziness, and reactions related to blood draws/infusion sites. All TEAEs were mild to moderate in severity. The results show that an increase in insulin detemir dose will result in a similar increase in insulin detemir concentration in the two ethnic groups. Therefore, therapeutic dosing of insulin detemir is expected to be similar in both ethnic groups, with no special dose adjustment or algorithm based on race. Insulin detemir at 0.19, 0.38, and 0.75 U/kg was generally well tolerated in both Japanese and Caucasian subjects.

Correlation of anti-Pru p 3 IgE levels with severity of peach allergy reactions in children

BACKGROUND

Peach allergy is regarded as one of the most important fresh fruit allergies. Data are available on the state-of-the-art diagnosis, including food challenges, and a component-resolved diagnosis. However, the roles played by different peach allergens with respect to symptom severity are not completely understood.

OBJECTIVE

To evaluate the role of serum specific IgE to peach and recombinant allergens in the diagnosis of peach allergies in Italian children.

METHODS

Forty-four children with peach allergy confirmed by a placebo-controlled food challenge were divided into 2 groups based on their symptom severity: patients with mild oral allergy syndrome (OAS) and patients with systemic symptoms (SS). The presence of specific IgE to peach and rPru p 1, rPru p 3, and rPru p 4 was determined.

RESULTS

The presence of specific IgE to Pru p 4 and Pru p 1 was found significantly more frequently in patients with OAS, whereas specific IgE to Pru p 3 was not found significantly more frequently in patients with SS. Only anti-rPru p 4 IgE levels were significantly higher in patients with OAS, whereas no significant differences were found in anti-rPru p 1 and anti-rPru p 3 IgE levels between patients with OAS compared with patients with SS.

CONCLUSION

In Italian children with peach allergies, the presence of specific IgE to Pru p 3 is not associated with SS, and the levels of specific IgE to Pru p 3 do not correlate with the severity of the reactions.

Molecular allergology in practice: an unusual case of LTP allergy

The authors describe an unusual case of LTP allergy. A 35 years old patient presented repeated episodes of angiooedema after food intake and complained 10 years ago of contact urticaria and rhinoconjunctivitis when exposed to cannabis leaves and to marijuana smoke. The suspected responsible foods, such as wheat flour in bread, are known to contain LTR Oral syndrome occurred after ingestion of walnuts. Cutaneous tests confirmed immediate responses to several flours and nuts and also to cannabis leaf and flower. A few months later he had similar accidents following peach ingestion and drinking of beer and several wines which all induced positive skin tests. Serological investigations using ImmunoCAP and ISAC microarray confirmed IgE positivity for n Pru p3, r Cor a 8 and n Art v3. It was assumed that sensitization to LTP, the major allergen of cannabis, was responsible of the primary sensitization and induced further LTP food allergies.

Prevalence of sensitization to lipid transfer proteins and profilins in a population of 430 patients in the south of Madrid

BACKGROUND

Lipid transfer proteins (LTPs) and profilins are the most important panallergens in the management of patients who are allergic to pollen and plant food in our area. LTPs are highly stable proteins that can induce systemic symptoms after ingestion. Profilins are labile proteins that are present in pollens and vegetables. Considered markers of several types of pollen sensitization, they are responsible for cross-reactivity between pollens and vegetables. The objective of this study was to assess the frequency of sensitization to LTP and profilin using skin prick tests (SPTs) in patients referred to our allergy unit for any complaint (not only pollen and plant food allergy).

METHODS

The study sample comprised 430 consecutive patients who were evaluated using their medical history and SPTs with pollen, date palm profilin, and peach extract enriched in Pru p 3 (30 g/mL) as an LTP marker.

RESULTS

We found that 52 (12.1%) patients were sensitized to profilin and 53 (12.3%) to LTP. Pollen allergy was diagnosed in 53% and plant food allergy in 11%. In the LTP-sensitized group and the profilin-sensitized group, 37.7% and 34.6% of the patients had plant food allergy, respectively. Thirty-three patients (62.3%) were sensitized to LTP but had no symptoms after eating vegetables.

CONCLUSIONS

To the best of our knowledge, this is the first study to analyze the real rate of sensitization to profilin and LTP in a population sensitized to allergens other than pollens and plant foods. Twelve percent of patients were sensitized to both profilin and LTP. A large proportion of LTP-sensitized patients had no symptoms at the time of the study.

Two new drugs for chronic ITP

Romiplostim (Nplate - Amgen), a recombinant fusion protein injected subcutaneously, and eltrombopag (Promacta - GlaxoSmithKline), a non-peptide taken orally, have been approved by the FDA for treatment of chronic immune thrombocytopenic purpura (ITP) refractory to corticosteroids, immunoglobulins and/or splenectomy.

Safety concerns for the potential use of cyanovirin-N as a microbicidal anti-HIV agent

Based on its antiviral activity profile, cyanovirin-N (CV-N) holds great potential for anti-HIV microbicidal application. However, limited data are available on the possible side-effects of this lectin. A detailed investigation was carried out to obtain better insights in the cytotoxic, inflammatory and (anti)-proliferative properties of CV-N in comparison with several other plant-derived lectins. CV-N affected the cell morphology of PBMCs and enhanced the expression of the cellular activation markers CD25, CD69 and HLA-DR. PBMCs activated by CV-N were more susceptible for R5 HIV-1 infection. In addition, CV-N exerted a pronounced mitogenic activity and significantly enhanced in PBMCs the production of a wide variety of cytokines, as determined by the Bio-Plex human cytokine 27-plex array system. In comparison, other lectins obtained from Hippeastrum hybrid, Galanthus nivalis, and Urtica dioica induced markedly less, if any, stimulatory effects. So, the use of CV-N may be accompanied by various stimulatory effects that may compromise its application for microbicidal use.

Efficacy of romiplostim in patients with chronic immune thrombocytopenic purpura: a double-blind randomised controlled trial

BACKGROUND

Chronic immune thrombocytopenic purpura (ITP) is characterised by accelerated platelet destruction and decreased platelet production. Short-term administration of the thrombopoiesis-stimulating protein, romiplostim, has been shown to increase platelet counts in most patients with chronic ITP. We assessed the long-term administration of romiplostim in splenectomised and non-splenectomised patients with ITP.

METHODS

In two parallel trials, 63 splenectomised and 62 non-splenectomised patients with ITP and a mean of three platelet counts 30x10(9)/L or less were randomly assigned 2:1 to subcutaneous injections of romiplostim (n=42 in splenectomised study and n=41 in non-splenectomised study) or placebo (n=21 in both studies) every week for 24 weeks. Doses of study drug were adjusted to maintain platelet counts of 50x10(9)/L to 200x10(9)/L. The primary objectives were to assess the efficacy of romiplostim as measured by a durable platelet response (platelet count > or =50x10(9)/L during 6 or more of the last 8 weeks of treatment) and treatment safety. Analysis was per protocol. These studies are registered with ClinicalTrials.gov, numbers NCT00102323 and NCT00102336.

FINDINGS

A durable platelet response was achieved by 16 of 42 splenectomised patients given romplostim versus none of 21 given placebo (difference in proportion of patients responding 38% [95% CI 23.4-52.8], p=0.0013), and by 25 of 41 non-splenectomised patients given romplostim versus one of 21 given placebo (56% [38.7-73.7], p<0.0001). The overall platelet response rate (either durable or transient platelet response) was noted in 88% (36/41) of non-splenectomised and 79% (33/42) of splenectomised patients given romiplostim compared with 14% (three of 21) of non-splenectomised and no splenectomised patients given placebo (p<0.0001). Patients given romiplostim achieved platelet counts of 50x10(9)/L or more on a mean of 13.8 (SE 0.9) weeks (mean 12.3 [1.2] weeks in splenectomised group vs 15.2 [1.2] weeks in non-splenectomised group) compared with 0.8 (0.4) weeks for those given placebo (0.2 [0.1] weeks vs 1.3 [0.8] weeks). 87% (20/23) of patients given romiplostim (12/12 splenectomised and eight of 11 non-splenectomised patients) reduced or discontinued concurrent therapy compared with 38% (six of 16) of those given placebo (one of six splenectomised and five of ten non-splenectomised patients). Adverse events were much the same in patients given romiplostim and placebo. No antibodies against romiplostim or thrombopoietin were detected.

INTERPRETATION

Romiplostim was well tolerated, and increased and maintained platelet counts in splenectomised and non-splenectomised patients with ITP. Many patients were able to reduce or discontinue other ITP medications. Stimulation of platelet production by romiplostim may provide a new therapeutic option for patients with ITP.

The activation of somatostatinergic receptors by either somatostatin-14 or cortistatin-17 often inhibits ACTH hypersecretion in patients with Cushing's disease

OBJECT

Somatostatin (SS) is known to inhibit GH and insulin, while its effect on corticotrope secretion is controversial: inhibition of ACTH secretion by agonists activating somatostatinergic receptors (sst)-2 and sst-5 was reported in vitro. Cortistatin (CST) not only binds all sst receptor subtypes but also possesses central actions that are not shared by SS.

DESIGN

In nine patients with Cushing's disease (CD), ACTH, cortisol, GH, insulin, and glucose levels were studied during 120-min i.v. infusion of SS-14 (2.0 microg/kg per h), CST-17 (2.0 microg/kg per h) or saline.

RESULTS

Both SS or CST significantly affected the hypothalamic-pituitary-adrenal axis. Cortisol was decreased to the same extent by either SS or CST (P < 0.05). Both SS and CST decreased ACTH, although statistical difference was reached only during CST (P < 0.05). Analyzing the individual responses as areas under curve (AUCs), a clear and consensual inhibition of ACTH and cortisol under either SS or CST was recorded in five out of nine patients. Both SS or CST inhibited (P < 0.05) insulin, that even showed a rebound (P < 0.01) at the end of infusion. GH was not modified by either peptide.

CONCLUSION

SS and CST often display similar inhibitory effects on the HPA axis in CD. The activation of sst receptors by both peptides is followed in almost 50% of patients by a remarkable inhibition of ACTH and cortisol hypersecretion. These findings reinforce the view that sst receptors are involved in the control of the secretory activity of tumoral corticotropic cells.

Detection of Some Safe Plant-Derived Foods for LTP-Allergic Patients

BACKGROUND

Lipid transfer protein (LTP) is a widely cross-reacting plant pan-allergen. Adverse reactions to Rosaceae, tree nuts, peanut, beer, maize, mustard, asparagus, grapes, mulberry, cabbage, dates, orange, fig, kiwi, lupine, fennel, celery, tomato, eggplant, lettuce, chestnut and pineapple have been recorded.

OBJECTIVE

To detect vegetable foods to be regarded as safe for LTP-allergic patients.

METHODS

Tolerance/intolerance to a large spectrum of vegetable foods other than Rosaceae, tree nuts and peanut was assessed by interview in 49 subjects monosensitized to LTP and in three distinct groups of controls monosensitized to Bet v 1 (n = 24) or Bet v 2 (n = 18), or sensitized to both LTP and birch pollen (n = 16), all with a history of vegetable food allergy. Patients and controls underwent skin prick test (SPT) with a large spectrum of vegetable foods. The absence of IgE reactivity to foods that were negative in both clinical history and SPT was confirmed by immunoblot analysis and their clinical tolerance was finally assessed by open oral challenge (50 g per food).

RESULTS

All patients reported tolerance and showed negative SPT to carrot, potato, banana and melon; these foods scored positive in SPT and elicited clinical symptoms in a significant proportion of patients from all three control groups. All patients tolerated these four foods on oral challenge. Immunoblot analysis confirmed the lack of IgE reactivity to these foods by LTP-allergic patients.

CONCLUSION

Carrot, potato, banana and melon seem safe for LTP-allergic patients. This finding may be helpful for a better management of allergy to LTP.

Comparative in silico analysis of two vaccine candidates for group A streptococcus predicts that they both may have similar safety profiles

BACKGROUND

Concerns of immune cross-reactivity, between epitopes of the group A streptococcal (GAS) M-proteins and host proteins have hindered the progress of an effective GAS vaccine. An ideal M-protein based subunit vaccine should not elicit heart tissue cross-reactive antibody responses and should not activate M-protein specific CD4+ T-cells. In the current study we used a bioinformatic and immunoinformatic approach to assess the safety of J8 and J14, chimeric vaccine constructs containing a GAS derived M-protein epitope embedded in flanking GCN4 region. We demonstrate that at the primary amino acid level J8 and J14 show very little homology to human proteins. ProPred, RANKPEP and HLABIND algorithms failed to predict significant binding between the M-protein specific regions of J8 and J14 and class II binding alleles. A single peptide was predicted to bind to HLA class I allele B_2705. This data was supported by cellular proliferation assays demonstrating few peripheral blood mononuclear cells (PBMCs) from donors respond to J8 and J14. Reassuringly, there was no correlation between proliferation to these peptides, and proliferation to host proteins. This data suggests that J8 and J14 are unlikely to induce cross-reactive immune responses, and will be safe for use in humans.

An open-label, unit dose-finding study of AMG 531, a novel thrombopoiesis-stimulating peptibody, in patients with immune thrombocytopenic purpura

Abstract The objective of this open label, phase 1-2, multicentre trial was to evaluate the safety of AMG 531, a novel thrombopoiesis-stimulating peptibody, and its effect on platelet counts in adults with immune thrombocytopenic purpura. Four patients were assigned to each of four unit-dose cohorts: 30, 100, 300 or 500 microg, administered subcutaneously on days 1 and 15 (or day 22 if the day 15 platelet count was >50 x 10(9)/l). Safety was assessed by adverse event (AE) monitoring, clinical laboratory studies and antibody assays. Platelet response was defined as a platelet count double the baseline value and between 50 and 450 x 10(9)/l. Sixteen patients (10 women) were enrolled. The 500-microg cohort was discontinued because the first patient's platelet count became unacceptably high. AEs were generally expected and mild or moderate; the most frequent was headache (eight of 16 patients). Two patients experienced serious AEs related to AMG 531 (severe headache and elevated serum lactic dehydrogenase; thrombocytopenia). Platelet responses occurred with all doses and with a dose equivalent to >/=1 microg/kg in eight of 11 patients. In summary, patients tolerated AMG 531 well at the doses tested. No anti-AMG or antithrombopoietin antibodies were detected. Doses equivalent to >/=1 microg/kg increased platelet counts.

AMG 531, a thrombopoiesis-stimulating protein, for chronic ITP

BACKGROUND

Most current treatments for chronic immune thrombocytopenic purpura (ITP) act by decreasing platelet destruction. In a phase 1-2 study, we administered a thrombopoiesis-stimulating protein, AMG 531, to patients with ITP.

METHODS

In phase 1, 24 patients who had received at least one treatment for ITP were assigned to escalating-dose cohorts of 4 patients each and given two identical doses of AMG 531 (0.2 to 10 microg per kilogram of body weight). In phase 2, 21 patients were randomly assigned to receive six weekly subcutaneous injections of AMG 531 (1, 3, or 6 microg per kilogram) or placebo. The primary objective was to assess the safety of AMG 531; the secondary objective was to evaluate platelet counts during and after treatment.

RESULTS

No major adverse events that could be attributed directly to AMG 531 occurred during the treatment period; 4 of 41 patients had transient post-treatment worsening of thrombocytopenia. In phase 1, a platelet count that was within the targeted range (50,000 to 450,000 per cubic millimeter) and at least twice the baseline count was achieved in 4 of 12 patients given 3, 6, or 10 mug of AMG 531 per kilogram. Overall, a platelet count of at least 50,000 per cubic millimeter was achieved in 7 of 12 patients, including 3 with counts exceeding 450,000 per cubic millimeter. Increases in the platelet count were dose-dependent; mean peak counts were 163,000, 309,000, and 746,000 per cubic millimeter with 3, 6, and 10 microg of AMG 531 per kilogram [corrected], respectively. In phase 2, the targeted platelet range was achieved in 10 of 16 patients treated with 1 or 3 mug of AMG 531 per kilogram per week for 6 weeks. Mean peak counts were 135,000, 241,000, and 81,000 per cubic millimeter in the groups that received the 1-mug dose, the 3-mug dose, and placebo, respectively.

CONCLUSIONS

AMG 531 caused no major adverse events and increased platelet counts in patients with ITP. (ClinicalTrials.gov number, NCT00111475 [ClinicalTrials.gov].).

Drug evaluation: AMG-531 for the treatment of thrombocytopenias

Amgen Inc is developing AMG-531, a peptibody that binds to the thrombopoietin receptor Mpl, for the potential treatment of immune thrombocytopenic purpura (ITP), chemotherapy-induced thrombocytopenia (CIT) and thrombocytopenia in myelodysplastic syndrome (MDS). Results of the US phase III trial in ITP are expected to be available in the second half of 2006, while a phase II trial in CIT is still underway. A Japanese phase II ITP study has been initiated, as has a phase II trial of MDS patients in the US and France.

Raising high-density lipoprotein with cholesteryl ester transfer protein inhibitors

Cholesteryl ester transfer protein (CETP) catalyzes the transfer of cholesteryl ester from high-density lipoprotein (HDL) to apolipoprotein B-containing lipoproteins in exchange for triglyceride, and thereby plays a major role in lipoprotein metabolism. The reciprocal increase in HDL cholesterol (HDL-C) and decrease in low-density lipoprotein cholesterol (LDL-C) associated with CETP deficiency has led to the search for synthetic CETP inhibitors over the past 15 years. Several potent inhibitors have been identified, two of which--JTT-705 and torcetrapib--are undergoing clinical trials. Recent reports that torcetrapib is able to simultaneously raise HDL-C twofold and lower LDL-C by < or = 42% has heightened interest in this new class of agents. Upcoming results from Phase III trials of torcetrapib should provide anatomical measurements of atherosclerosis and thus the first assessment of therapeutic benefit.

Cortistatin-17 and somatostatin-14 display the same effects on growth hormone, prolactin, and insulin secretion in patients with acromegaly or prolactinoma

CONTEXT

Cortistatin binds all somatostatin receptor subtypes but also has particular central actions; moreover, a specific cortistatin receptor has also been discovered.

OBJECTIVE

We compared the endocrine effects of cortistatin-17 with those of somatostatin-14 in patients with acromegaly (ACRO) or prolactinoma (PRLOMA). Normal subjects (NS) were studied as control group.

DESIGN

All subjects underwent the following tests: 1) saline, 2) somatostatin-14 (2.0 microg/kg.h iv, 0-120 min) and 3) cortistatin-17 (2.0 microg/kg.h iv, 0-120 min) infusion.

RESULTS

Cortistatin-17 and somatostatin-14 inhibited GH secretion to the same extent in ACRO (P < 0.05) and NS (P < 0.01). Cortistatin-17 and somatostatin-14 inhibited PRL secretion in PRLOMA (P < 0.05), to some extent in ACRO (P value not significant), but not in NS. Insulin secretion was inhibited by both cortistatin-17 and somatostatin-14 to the same extent in all groups (P < 0.05).

CONCLUSIONS

Cortistatin-17 and somatostatin-14 display the same effects on GH, PRL, and insulin secretion in patients with ACRO or PRLOMA.

Pharmacodynamics and pharmacokinetics of AMG 531, a novel thrombopoietin receptor ligand

OBJECTIVE

The objective of this study was to evaluate the tolerability, pharmacodynamics, and pharmacokinetics of AMG 531, a novel thrombopoietin receptor ligand, after a single intravenous or subcutaneous injection in healthy subjects.

METHODS

This was a first-in-human randomized, double-blind, placebo-controlled study with 48 subjects. Six subjects in each cohort were sequentially randomized in a 2:1 ratio to receive a single injection of AMG 531 or placebo. The dose ranges investigated were 0.3 to 10.0 microg/kg and 0.1 to 2.0 microg/kg via the intravenous and subcutaneous dosing routes, respectively. The pharmacodynamic response of AMG 531 was measured as the elevation in platelet counts. AMG 531 serum levels were determined by use of a validated enzyme-linked immunosorbent assay.

RESULTS

Single intravenous or subcutaneous administration of AMG 531 induced a dose-dependent increase in platelet count in healthy subjects, with peak platelet count being achieved on days 12 to 16. The highest intravenous dose, 10.0 microg/kg, caused a nearly 6-fold increase in platelet count. The maximum increase for this cohort occurred on day 15, and the mean platelet count was 1380 x 10(9)/L (range, 923-1790 x 10(9)/L). Of 8 subjects receiving the 2.0-microg/kg subcutaneous dose, 6 had peak platelet levels that were double the baseline value. Platelet count was elevated to a similar extent after single intravenous or subcutaneous administration of AMG 531 at the same dose level (1.0 microg/kg), even though the subcutaneous serum levels were barely detectable. Platelet counts were close to the baseline value by day 28. After a single intravenous administration, the pharmacokinetics of AMG 531 was nonlinear in the 0.3- to 10.0-microg/kg dose range. Most AMG 531 serum levels fell below the assay's lower quantitation limit of 18 pg/mL after a single subcutaneous dose. There were no serious or life-threatening adverse events reported in this study. The most frequently reported events were mild to moderate headache and sore throat.

CONCLUSION

AMG 531 was well tolerated in this study and was effective at raising platelet counts in healthy volunteers after single intravenous or subcutaneous administration.

Effects of QD insulin detemir or neutral protamine Hagedorn on blood glucose control in patients with type I diabetes mellitus using a basal-bolus regimen

OBJECTIVE

The purpose of this trial was to compare the effects of QD basal insulin replacement using insulin detemir versus neutral protamine Hagedorn (NPH) insulin in basal-bolus therapy in combination with regular human insulin (HI) in patients with type 1 diabetes mellitus (DM).

METHODS

This was a 6-month, prospective, randomized, open-label, controlled, parallel-group trial conducted at 92 sites in Europe and Australia. The trial population included men and women with type 1 DM for at least 1 year aged > or = 18 years with glycosylated hemoglobin (HbA(1c)) <== 12% already taking QD basal-bolus treatment with an intermediate- or long-acting insulin and a fast-acting human insulin or insulin analogue as bolus insulin. Patients were randomly assigned (2:1) to 6 months of treatment with insulin detemir or NPH at bedtime in combination with HI with main meals. Main outcome measures were blood glucose control as assessed by HbA(1c), fasting plasma glucose (FPG), 9-point self-monitored blood glucose (SMBG) profiles, 24-hour continuous blood glucose profiles, hypoglycemia, weight gain, and adverse events.

RESULTS

Of the 749 patients randomized to treatment, 747 were exposed to trial products and included in the intent-to-treat analysis set. Seven hundred patients completed the trial: 465 (94.7%) in the insulin detemir group and 235 (91.8%) in the NPH group. After 6 months, FPG was lower with insulin detemir than with NPH (-1.16 mmol/L difference; P = 0.001), whereas HbA(1c) did not differ significantly between treatments (-0.12% [95% CI, -0.25 to 0.02]; P = NS). Day-to-day variability in self-measured fasting blood glucose was lower with insulin detemir (SD, 2.82 vs 3.60 mmol/L; P < 0.001). The overall shape of the 9-point SMBG profiles differed significantly between treatments (P = 0.006), with lower glucose levels before breakfast with insulin detemir than with NPH (P < 0.001). There was a 26% reduction in the relative risk of nocturnal hypoglycemia with insulin detemir compared with NPH (P = 0.003). Gain in body weight was significantly lower after 6 months with insulin detemir than with NPH (-0.54 kg difference; P = 0.024). The frequency and type of adverse events were similar between treatment groups.

CONCLUSIONS

In this study, QD administration of insulin detemir at bedtime resulted in lower fasting blood glucose levels with less day-to-day variability and less fluctuation from ean blood glucose levels over 24 hours than NPH insulin, combined with an overall reduction in the risk of nocturnal hypoglycemia. These findings suggest that evening administration of insulin detemir may provide an opportunity to further improve fasting blood glucose targets.

Lower within-subject variability of insulin detemir in comparison to NPH insulin and insulin glargine in people with type 1 diabetes

The aim of this randomized double-blind study was to compare the within-subject variability of the glucose-lowering effect of a novel insulin analog, insulin detemir, with that of insulin glargine and NPH insulin in people with type 1 diabetes. Fifty-four subjects (32 males and 22 females, age 38 +/- 10 years [mean +/- SD], BMI 24 +/- 2 kg/m(2), HbA(1c) 7.5 +/- 1.2%, diabetes duration 18 +/- 9 years) participated in this parallel group comparison. Each subject received four single subcutaneous doses of 0.4 units/kg of either insulin detemir (n = 18), insulin glargine (n = 16), or human NPH insulin (n = 17) under euglycemic glucose clamp conditions (target blood glucose concentration 5.5 mmol/l) on four identical study days. The pharmacodynamic (glucose infusion rates [GIRs]) and pharmacokinetic (serum concentrations of insulin detemir, human insulin, and insulin glargine) properties of the basal insulin preparations were recorded for 24 h postdosing. Insulin detemir was associated with significantly less within-subject variability than both NPH insulin and insulin glargine, as assessed by the coefficient of variation (CV) for the pharmacodynamic end points studied [GIR-AUC((0-12 h)) 27% (detemir) vs. 59% (NPH) vs. 46% (glargine); GIR-AUC((0-24 h)) 27 vs. 68 vs. 48%; GIR(max) 23 vs. 46 vs. 36%; P < 0.001 for all comparisons]. Insulin detemir also provided less within-subject variability in the pharmacokinetic end points: maximal concentration (C(max)) 18 vs. 24 vs. 34%; INS-AUC((0- infinity )) 14 vs. 28 vs. 33%. The results suggest that insulin detemir has a significantly more predictable glucose-lowering effect than both NPH insulin and insulin glargine.

RGSZ1 and GAIP regulate mu- but not delta-opioid receptors in mouse CNS: role in tachyphylaxis and acute tolerance

In the CNS, the regulators of G-protein signaling (RGS) proteins belonging to the Rz subfamily, RGS19 (G(alpha) interacting protein (GAIP)) and RGS20 (Z1), control the activity of opioid agonists at mu but not at delta receptors. Rz proteins show high selectivity in deactivating G(alpha)z-GTP subunits. After reducing the expression of RGSZ1 with antisense oligodeoxynucleotides (ODN), the supraspinal antinociception produced by morphine, heroin, DAMGO ([D-Ala2, N-MePhe4,Gly-ol5]-enkephalin), and endomorphin-1 was notably increased. No change was observed in the effect of endomorphin-2. This agrees with the proposed existence of different mu receptors for the endomorphins. The activities of DPDPE ([D-Pen2,5]-enkephalin) and [D-Ala2] deltorphin II, agonists at delta receptors, were also unchanged. Knockdown of GAIP and of the GAIP interacting protein C-terminus (GIPC) led to changes in agonist effects at mu but not at delta receptors. The impairment of RGSZ1 extended the duration of morphine analgesia by at least 1 h beyond that observed in control animals. CTOP (Cys2, Tyr3, Orn5, Pen7-amide) antagonized morphine analgesia when given during the period in which the effect of morphine was enhanced by RGSZ1 knockdown. Thus, in naive mice, morphine tachyphylaxis originated in the presence of the opioid agonist and during the analgesia time course. The knockdown of RGSZ1 facilitated the development of tolerance to a single dose of morphine and accelerated tolerance to continuous delivery of the opioid. These results indicate that mu but not delta receptors are linked to Rz regulation. The mu receptor-mediated activation of Gz proteins is effective at recruiting the adaptive mechanisms leading to the development of opioid desensitization.

Insulin detemir is characterized by a consistent pharmacokinetic profile across age-groups in children, adolescents, and adults with type 1 diabetes

OBJECTIVE

This trial aimed to characterize for the first time the pharmacokinetic profile of insulin detemir, the novel soluble basal insulin analog, in children and adolescents compared with adults. Comparisons were also made with NPH insulin to determine any between-treatment difference in the effect of age on pharmacokinetic profile.

RESEARCH DESIGN AND METHODS

This single-center, open-label, randomized, crossover trial included children (aged 6-12 years, n = 13), adolescents (aged 13-17 years, n = 10), and adults (aged 18-65 years, n = 11) of both sexes. Subjects were given single doses of 0.5 units/kg s.c. insulin detemir or 0.5 IU/kg NPH insulin on 2 separate days. Serial blood sampling was performed for 24 h for analysis of serum insulin detemir, human insulin, and glucose concentrations.

RESULTS

The mean pharmacokinetic profile of insulin detemir was similar across all three age-groups. This was determined by statistical analyses of the data, which showed no overall age effect or between-group differences when pairwise comparisons were made between children (or adolescents) and adults on the parameters of the area under the curve (AUC), AUC from zero to infinity, AUC from 0 to 24 h [AUC((0-24 h))], and the maximum concentration measured during the 24 h after closing. No overall age effect for AUC((0-24 h)) and C(max) was detected for NPH insulin, but data were only analyzable from seven adults and pairwise comparisons did indicate that children and adults had different pharmacokinetic profiles. Less total variability in the pharmacokinetics of insulin detemir than NPH insulin was indicated by lower coefficients of variation in AUC, C(max), and time to maximum concentration in all three age-groups.

CONCLUSIONS

The data suggest that insulin detemir can be used in children and adolescents with type 1 diabetes using titration guidelines similar to those used in adults. Moreover, insulin detemir may offer the advantage of greater predictability of response in comparison to NPH insulin due to lower total variability and a lesser degree of kinetic disparity across age-groups.

[In vitro evaluation of the safety and biological activity of recombinant Helicobacter pylori blood group antigen-binding adhesin]

OBJECTIVE

To evaluate the safety and biological activity of recombinant Helicobacter pylori (Hp) blood group antigen- binding adhesin (rBabA ) in vitro so as to investigate the feasibility of using rBabA as a Hp vaccine.

METHODS

ELISA was used to measure rBabA-specific antibody in the serum of Hp-infected patients, and the proliferation of T lymphocytes in response to rBabA was examined by MTT assay. T cell apoptosis induced by rBabA was detected by diphenylamine assay. The effect of rBabA on Hp binding into human gastric carcinoma cell line(MGC-803) was determined by light microscopy.

RESULTS

rBabA did not induce T cell apoptosis in BabA antibody- negative patients and was capable of stimulating T cell proliferation in rBabA antibody-positive patients. In the serum samples from 38 Hp-infected patients, the rBabA antibody positivity rate was 18.4%. rBabA could partially inhibit the binding of Hp to gastric epithelial cells. Under light microscope, the adhesion of Hp to MGC-803 was significantly inhibited by rBabA in comparison with negative control with PBS pretreatment.

CONCLUSION

rBabA proves to be a safe and immunogenic bacterial component of Hp, which stimulates humoral and cellular immunity and can be a hopeful antigen targeting at BabA2 gene-positive Hp strain for the development of Hp vaccine.

[Cross-reactivity between fruit and vegetables]

Vegetable foods are the most frequent cause of food allergy after the age of 5 years. The most commonly implicated foods are fruit and dried fruits, followed in Spain by legumes and fresh garden produce. In patients allergic to fruit and garden produce, multiple sensitizations to other vegetable products, whether from the same family or taxonomically unrelated, are frequent, although they do not always share the same clinical expression. Furthermore, more than 75 % of these patients are allergic to pollen, the type of pollen varying in relation to the aerobiology of the area. The basis of these associations among vegetable foods and with pollens lies in the existence of IgE antibodies against "panallergens", which determines cross-reactivity. Panallergens are proteins that are spread throughout the vegetable kingdom and are implicated in important biological functions (generally defense) and consequently their sequences and structures are highly conserved. The three best-known groups are allergens homologous to Bet v 1, profilins, and lipid transfer proteins (LTP). Allergens homologous to Bet v 1 (major birch pollen allergen) constitute a group of defense proteins (PR-10), with a molecular weight of 17 kDa, which behave as major allergens in patients from northern and central Europe with allergy to vegetables associated with birch pollen allergy. In these patients, the primary sensitization seems to be produced through the inhalation route on exposure to birch pollen. The symptomatology characteristically associated with sensitization to this family of allergens is oral allergy syndrome (OAS). Profilins are highly conserved proteins in all eukaryotic organisms and are present in pollen and a wide variety of vegetable foods. They have a molecular weight of 14 kDa and present a high degree of structural homology as well as marked cross-reactivity among one another. The presence of anti-profilin IgE broadens the spectrum of sensitizations to vegetable foods detected through skin tests and/or in vitro tests but whether it correlates with the clinical expression of food allergy is unclear.LTPs are the most commonly implicated allergens in allergy to Rosaceae fruits in patients from the Mediterranean area without birch pollen sensitization. LTPs are a family of 9kDA polypeptides, widely found in the vegetable kingdom and implicated in cuticle formation and defense against pathogens (PR-14). They are thermostable and resistant to pepsin digestion, which makes them potent food allergens and explains the frequent development of systemic symptoms (urticaria, anaphylaxis) in patients allergic to Rosaceae fruits in Spain. LTPs have also been identified in other vegetable foods and in pollens and a marked degree of cross-reactivity among them has been demonstrated, which may explain (together with profilin) the frequency of individuals sensitized to vegetable foods in the Mediterranean area.

Insulin detemir. Novo Nordisk

Insulin detemir (NN-304) is a soluble, long-acting insulin analog being developed by Novo Nordisk for the potential treatment of type 1 and 2 diabetes. As of February 2003, Novo Nordisk was expecting both US and EU approval in the first half of 2004. In December 2002, Novo Nordisk submitted an NDA to the FDA and an NDS to the Canadian Biologics & Genetics Therapeutic Directorate for the approval of insulin detemir for the treatment of diabetes mellitus.

Insulin detemir is associated with more predictable glycemic control and reduced risk of hypoglycemia than NPH insulin in patients with type 1 diabetes on a basal-bolus regimen with premeal insulin aspart

OBJECTIVE

Insulin detemir is a soluble basal insulin analog with a unique mechanism of protracted action designed to reduce the variability associated with conventional basal insulins. This trial compared the glycemic control, risk of hypoglycemia, and effect on body weight of insulin detemir and NPH insulin in patients with type 1 diabetes treated with rapid-acting insulin aspart at meals.

RESEARCH DESIGN AND METHODS

This study was a 6-month multinational open parallel-group comparison conducted at 46 centers in five countries and included 448 patients with type 1 diabetes randomized 2:1 to insulin detemir or NPH insulin, respectively.

RESULTS

After 6 months, comparable HbA(1c) levels were found between the two treatment groups. Fasting plasma glucose tended to be lower in patients treated with insulin detemir, but this difference was not statistically significant (-0.76 mmol/l, P = 0.097). Within-subject variation in self-measured fasting blood glucose was lower with insulin detemir than with NPH insulin (SD 3.37 vs. 3.78 mmol/l, P < 0.001). Risk of hypoglycemia was 22% lower with insulin detemir than with NPH insulin (P < 0.05) and 34% lower for nocturnal (2300-0600) hypoglycemia (P < 0.005). Nightly plasma glucose profiles were smoother and more stable with insulin detemir (P = 0.05). Body weight was significantly lower with insulin detemir at the end of the trial (P < 0.001).

CONCLUSIONS

Treatment with insulin detemir resulted in more predictable glycemic control, with smoother plasma glucose profiles than NPH insulin and a significant reduction in the risk of hypoglycemia. The reduction in body weight with insulin detemir is a potential additional advantage. Regimens optimized for insulin detemir may be able to improve glycemic control beyond that possible with NPH insulin.

Treatment of active Crohn's disease with onercept (recombinant human soluble p55 tumour necrosis factor receptor): results of a randomized, open-label, pilot study

BACKGROUND

Monoclonal antibodies to the pro-inflammatory cytokine tumour necrosis factor-alpha have shown efficacy in treating Crohn's disease, but can be immunogenic. Soluble tumour necrosis factor-binding proteins are being studied as potential alternative anti-tumour necrosis factor agents in Crohn's disease.

AIM

To investigate the safety and efficacy of onercept, a recombinant form of the natural human soluble p55 tumour necrosis factor receptor, in the treatment of patients with active Crohn's disease.

METHODS

In a pilot study, 12 patients with active Crohn's disease were randomized to receive onercept at either 11.7 or 50 mg three times weekly for 2 weeks. Patients were followed up for 6 months after the end of treatment.

RESULTS

The Crohn's disease activity index decreased rapidly during treatment in both groups. Seven responses (Crohn's disease activity index decrease of 100 points) were observed over the first 6 weeks of the study, including five remissions (Crohn's disease activity index decrease of 150 points). Improvement was sustained for 2-4 months after stopping treatment. Treatment was well tolerated. No patients developed antibodies to onercept.

CONCLUSIONS

Neutralizing the activity of tumour necrosis factor-alpha with its soluble p55 receptor may be valuable in the treatment of patients with Crohn's disease. Larger placebo-controlled trials are indicated.

Pru p 3 (LTP) content in peach extracts

BACKGROUND

Lipid transfer proteins are molecules widely distributed in fruits. Sensitization to LTP is frequent in fruit sensitive patients. The aims of this study were to purify LTP and to assess the content of LTP in ripe peach peel and pulp extracts by ELISA inhibition using polyclonal antibodies.

METHODS

LTP was purified from ripe yellow peach peel by two different column chromatography methods. A polyclonal antibody was produced by injecting purified LTP into two New Zealand white rabbits. ELISA inhibition and rabbit monospecific polyclonal antibody were used to calculate the LTP content in Springcrest and Miraflores varieties of peach peel and pulp extracts. Purified LTP (2.5 mg/ml) was used to skin test 24 peach-sensitive patients.

RESULTS

The purified LTP showed a single band at approximately 9 kDa. The polyclonal antibody raised anti LTP recognized only the LTP molecule in the peach extracts. LTP content, expressed in micro g/mg of freeze-dried extract in four extracts were: yellow peach peel, 15.48; yellow peach pulp 2.25; red peach peel 14.67 and red peach pulp 1.84. Twenty patients (83.3%) had a positive skin test with purified LTP.

CONCLUSIONS

We have developed a system to determine the concentration of LTP in peach extracts. LTP in peel extracts is approximately seven times greater than in pulp.

Immunological cross-reactivity between lipid transfer proteins from botanically unrelated plant-derived foods: a clinical study

BACKGROUND

Lipid transfer proteins (LTP) are highly conserved and widely distributed throughout the plant kingdom. Recent studies demonstrated immunological cross-reactivity between LTP from many botanically unrelated fruits and vegetables and concluded that LTP are pan-allergens. This study aimed to evaluate the clinical relevance of such cross-reactivity in a group of subjects monosensitized to LTP.

METHODS

Twenty LTP-hypersensitive patients were selected from a population of about 600 subjects with history of Rosaceae allergy by means of: 1) negative skin prick test (SPT) with a commercial birch pollen extract; 2) positive SPT with a commercial plum extract, rich in LTP but virtually lacking both Bet v 1-like proteins and profilin; 3) in-vitro IgE reactivity to the 9-10 kDa fraction of peach peel or immunoblot with peach peel showing a single band at 10 kDa; and 4) total inhibition of reactivity to whole peach extract (containing Bet v 1-related allergen, profilin, and LTP) by purified peach LTP on enzyme-linked immunoassay (ELISA). Allergy to foods other than Rosaceae was ascertained by careful interview and analysis of medical recordings. SPT with a large series of plant-derived foods were carried out as well. The cross reactivity between LTPs from botanically unrelated plant-derived foods was assessed by ELISA inhibition tests using walnut and peanut extracts as substrate, and peach LTP as inhibitor.

RESULTS

All patients reported allergic reactions after the ingestion of at least one from a large number of vegetable foods other than Rosaceae, and in several cases clinical reactions were very severe (anaphylaxis, asthma, urticaria/angioedema). Nuts and peanuts were the most frequently reported causes of allergic reactions (80% and 40% of patients, respectively). All patients showed positive SPT to several non-Rosaceae food extracts. SPT with nuts, peanut, legumes, celery, rice, and corn were positive in the majority of patients. In ELISA inhibition studies, absorption of sera with peach LTP caused complete inhibition of IgE reactivity to walnut and peanut in all cases.

CONCLUSION

LTP is a clinically relevant pan-allergen. Most Rosaceae-allergic, LTP-hypersensitive patients experience adverse reactions after ingestion of botanically unrelated plant-derived foods as well. In view of the high prevalence and severity of the allergic reactions induced, hazelnut, walnut, and peanut should be regarded as potentially hazardous for these patients.

Microinjection of orexin into the rat nucleus tractus solitarius causes increases in blood pressure

Orexin A (OX-A) and orexin B (OX-B), also known as hypocretin-1 and hypocretin-2, have been suggested to play a role cardiovascular control. The nucleus tractus solitarius (NTS), located in the dorsal medulla plays an essential role in neural control of the cardiovascular system. Orexin-immunoreactive axons have been demonstrated within this nucleus suggesting that NTS may be a site through which OX acts to influence cardiovascular control. We report here that microinjection of OX-A into the NTS of urethane anesthetized rats causes increases in blood pressure (10(-9) M, mean AUC=607.1+/-65.65 mmHg s, n=5) and heart rate (10(-9) M, mean AUC=16.15+/-3.3 beats, n=5) which returns to baseline within 90 s. We show that these effects are dose related and site specific. Microinjection of OX-B into NTS elicited similar increases in BP (mean AUC=680.8+/-128.5 mmHg s, n=4) to that of OX-A suggesting specific actions at the OX(2)R receptor. These observations support the conclusion that orexins act as chemical messengers in the NTS likely influencing the excitability of cardiovascular neurons in this region and thus regulating global cardiovascular function.

Limb ischemia due to use of internal thoracic artery in coronary bypass

Immediately after undergoing coronary bypass grafting using the left internal thoracic artery, a 59-year-old man developed left leg ischemia. Right-to-left femoral artery crossover bypass was performed and the ischemia resolved. A 72-year-old man developed left calf pain 12 days after a similar procedure; peripheral angiography revealed stenosis of the abdominal aorta and distal peripheral arteries, which did not require intervention.

Okadaic acid induces epileptic seizures and hyperphosphorylation of the NR2B subunit of the NMDA receptor in rat hippocampus in vivo

Overactivation of N-methyl-D-aspartate (NMDA) glutamate receptors is closely related to epilepsy and excitotoxicity, and the phosphorylation of these receptors may facilitate glutamate-mediated synaptic transmission. Here we show that in awake rats the microinjection into the hippocampus of okadaic acid, a potent inhibitor of protein phosphatases 1 and 2A, induces in about 20 min intense electroencephalographic and behavioral limbic-type seizures, which are suppressed by the systemic administration of the NMDA receptor antagonist (+)-5-methyl-10,11-dihydro-5H-dibenzo-[a,d]cyclohepten-5,10-imine hydrogen maleate and by the intrahippocampal administration of 1-(5-isoquinolinesulfonyl)-2-methylpiperazine, an inhibitor of protein kinases. Two hours after okadaic acid, when the EEG seizures were intense, an increased serine phosphorylation of some hippocampal proteins, including an enhancement of the serine phosphorylation of the NMDA receptor subunit NR2B, was detected by immunoblotting. Twenty-four hours after okadaic acid a marked destruction of hippocampal CA1 region was observed, which was not prevented by the receptor antagonists. These findings suggest that hyperphosphorylation of glutamate receptors in vivo may result in an increased sensitivity to the endogenous transmitter and therefore induce neuronal hyperexcitability and epilepsy.