[Development and use of a domestic test system for diagnosis of tuberculous infection on the basis of quantitative analysis of interferon-gamma induction in whole blood samples in vitro, by using specific recombinant antigens]

A test system was developed to detect tuberculous infection by qualitative analysis of interferon-gamma (IFN-gamma) in the plasma samples after 20-24-hour incubation of whole blood samples in the presence of Mycobacterium tuberculosis (MBT) antigens: tuberculin PPD and a mixture of the MBT-specific recombinant antigens ESAT-6 and CFP-10. The analysis used 3 test tubes each containing 1 ml of heparinized venous blood, one of which served as a control; the other two test tubes were employed to measure antigen-induced IFN-gamma production. Whether this test system might be used to determine primary tuberculous infection was studied in 277 children and adolescents. The threshold diagnostic IFN-gamma induction level determined in the test tube containing a mixture of the antigens ESAT-6 and CFP-10 was ascertained. Postvaccine allergy was detectable if there was IFN-gamma induction in the test tube containing tuberculin and if there was no diagnostic IFN-gamma level in that containing the antigens ESAT-6 and CFP-10. The diagnostic sensitivity of detection of primary tuberculous infection was 97.6% with 94.4% specificity, which enabled this condition to be differentiated from postvaccine allergy. The level of antigen-induced IFN-gamma may be lower in relatively disseminated forms of pulmonary tuberculosis.

Toxoplasma gondii: usefulness of ROP1 recombinant antigen in an immunoglobulin G avidity assay for diagnosis of acute toxoplasmosis in humans

The results present in this study suggest that the Toxoplasma gondii recombinant ROP1 antigen in an IgG avidity test can be useful for detection of acute stage of infection. Specific antibodies of low avidity were detected in most of the sera from individuals with acute toxoplasmosis, while the absence or specific antibodies of high avidity were detected in sera from patients with chronic infection.

Utility of ProGRP determinations in cancer patients

BACKGROUND

The aim of this study was to assess the utility of ProGRP determinations in patients with selected cancer localization, during and after therapy.

MATERIALS AND METHODS

The study involved a reference group and a population of lung, breast, ovarian, and prostate cancer patients. ProGRP was evaluated using two-step chemiluminescent microparticle immunoassay (CMIA) manufactured by Abbott Diagnostics, and Architect i2000 analyzer.

RESULTS

During follow-up of SCLC patients, an increased value for ProGRP was found in 51% and for NSE only in 25.5% of the patients, whereas in NSCLC patients, percentages with elevated ProGRP and CYFRA 21-1 were 8.6% and 55.7%, respectively. SCLC patients also had the highest AUC values for ProGRP. In other cancers, the frequency of elevated ProGRP results were as follows: 13.1%--in breast cancer patients, 19.6%--in ovarian cancer patients, and 15.1%--in prostate cancer patients.

CONCLUSIONS

The presented study revealed that ProGRP is a tumor marker of choice in SCLC, because of its high diagnostic specificity in relation to the reference group and to the group with other malignancies.

Population pharmacokinetic model for human growth hormone in adult patients in chronic dialysis compared with healthy subjects

OBJECTIVE

To develop a population pharmacokinetic (PK) model of recombinant human growth hormone (rhGH) treatment in patients with end-stage renal disease (ESRD) and healthy volunteers (HVs), to support future study design.

DESIGN

This was an open, non-randomized, single-centre parallel-group study lasting 8-9 days. Various compartment models with first-order and Michaëlis-Menten absorption and elimination were explored. Eleven adult ESRD patients and 10 matched HVs received 50 microg/kg/day rhGH (subcutaneous (s.c.) injection) for 8 or 7 days, respectively. Blood samples were drawn every 30 min for 24h following dosing on Days 0, 7 and 8 (ESRD patients). Influence of the covariates subject group (ESRD/HV), gender, weight, and dialysis flow-rate on model parameters was examined.

RESULTS

The final model was one-compartmental with Michaëlis-Menten absorption and elimination. The following estimates were obtained: maximum absorption rate (VMA) - 11.3 microg/kg/h (both groups); amount of drug corresponding to half-maximum absorption rate (KMA) - 1.06 and 18.8 microg/kg (ESRD patients and HVs, respectively; P<0.001); maximum elimination rate (VM) - 9.37 and 13.0 microg/kg/h (ESRD patients and HVs, respectively; P<0.001); amount of drug corresponding to half-maximum elimination rate - 18.9 microg/kg (both groups). Significant differences in KMA and VM between HVs and ESRD patients corresponded to higher absorption and lower elimination rates in ESRD, but all GH profiles were back to baseline by 20-22h and no overall accumulation occurred. Simplified posterior predictive checks indicated that the model satisfactorily captured PK. All non-compartmental estimates for AUC(0-24h) and C(max) lay within 95% confidence limits of the simulated distributions.

CONCLUSIONS

A population PK model was established, which showed acceptable performance for trial-simulation purposes.

The diagnostic and prognostic value of ProGRP in lung cancer

AIM

To investigate the diagnostic and prognostic significance of pro-gastrin-releasing peptide (ProGRP) in non-small cell (NSCLC) and small cell lung cancer (SCLC) and compare this marker with other known serum markers in lung cancer.

PATIENTS AND METHODS

Serum levels of ProGRP, neuron-specific enolase (NSE), CYFRA 21-1 and carcinoembryonic antigen (CEA) were measured in 37 patients with benign pulmonary disease (BPD), 88 with advanced NSCLC and 37 with SCLC.

RESULTS

The ProGRP assay showed a better clinical performance than that of NSE in discriminating between SCLC and BPD or NSCLC, especially at specificity higher than 90%. ProGRP and NSE sensitivity in SCLC at 95% specificity versus the BPD group was 78.4% and 48.6%, (p=0.001) and at 97.7% specificity versus NSCLC, 75.7% and 37.8%, respectively (p=0.001). A significant association of low ProGRP levels with high-grade NSCLC tumors was found (p=0.002). A univariate analysis showed a significant association of ProGRP with survival both in NSCLC and SCLC (p=0.03 and p=0.04, respectively). In multivariate analysis, performance status (PS) and CYFRA 21-1 in NSCLC, and PS, CYFRA 21-1 and serum lactic dehydrogenase in SCLC were found as significant variables with an independent impact on survival.

CONCLUSION

ProGRP is a useful marker in SCLC, with diagnostic performance better than that of NSE and demonstrating association with survival in NSCLC and SCLC limited to univariate analysis.

Synergy between ficolin-2 and pentraxin 3 boosts innate immune recognition and complement deposition

The long pentraxin 3 (PTX3) is a multifunctional soluble pattern recognition molecule that is crucial in innate immune protection against opportunistic fungal pathogens such as Aspergillus fumigatus. The mechanisms that mediate downstream effects of PTX3 are largely unknown. However, PTX3 interacts with C1q from the classical pathway of the complement. The ficolins are recognition molecules of the lectin complement pathway sharing structural and functional characteristics with C1q. Thus, we investigated whether the ficolins (Ficolin-1, -2, and -3) interact with PTX3 and whether the complexes are able to modulate complement activation on A. fumigatus. Ficolin-2 could be affinity-isolated from human plasma on immobilized PTX3. In binding studies, Ficolin-1 and particularly Ficolin-2 interacted with PTX3 in a calcium-independent manner. Ficolin-2, but not Ficolin-1 and Ficolin-3, bound A. fumigatus directly, but this binding was enhanced by PTX3 and vice versa. Ficolin-2-dependent complement deposition on the surface of A. fumigatus was enhanced by PTX3. A polymorphism in the FCN2 gene causing a T236M amino acid change in the fibrinogen-like binding domain of Ficolin-2, which affects the binding to GlcNAc, reduced Ficolin-2 binding to PTX3 and A. fumigatus significantly. These results demonstrate that PTX3 and Ficolin-2 may recruit each other on pathogens. The effect was alleviated by a common amino acid change in the fibrinogen-like domain of Ficolin-2. Thus, components of the humoral innate immune system, which activate different complement pathways, cooperate and amplify microbial recognition and effector functions.

Systemic fate of the adipocyte-derived factor adiponectin

OBJECTIVE

The adipocyte-derived secretory protein adiponectin has been widely studied and shown to have potent insulin-sensitizing, antiapoptotic, and anti-inflammatory properties. While its biosynthesis is well understood, its fate, once in circulation, is less well established.

RESEARCH DESIGN AND METHODS

Here, we examine the half-life of adiponectin in circulation by tracking fluorescently labeled recombinant adiponectin in the circulation, following it to its final destination in the hepatocyte.

RESULTS

Despite its abundant presence in plasma, adiponectin is cleared rapidly with a half-life of approximately 75 min. A more bioactive version carrying a mutation at cysteine 39 is cleared within minutes. Even though steady-state levels of adiponectin differ between male and female mice, we failed to detect any differences in clearance rates, suggesting that differences in plasma are mostly due to differential production rates. In a metabolically challenged state (high-fat diet exposure or in an ob/ob background), adiponectin levels are reduced in plasma and clearance is significantly prolonged, reflecting a dramatic drop in adiponectin production levels.

CONCLUSIONS

Combined, these results show a surprisingly rapid turnover of adiponectin with multiple fat pads contributing to the plasma levels of adiponectin and clearance mediated primarily by the liver. It is surprising that despite high-level production and rapid clearance, plasma levels of adiponectin remain remarkably constant.

SLA/LP/tRNP((Ser)Sec) antigen in autoimmune hepatitis: identification of the native protein in human hepatic cell extract

A diagnostic subgroup of AIH type 1 is characterized by specific serum antibodies against soluble liver protein. The respective autoantigen was named SLA/LP/tRNP((Ser)Sec), after three homologous recombinant polypeptides were isolated from expression gene libraries. We analyzed human cultured liver cells for the human homologue of recombinant SLA/LP/tRNP((Ser)Sec) by antigen purification. In addition, a monoclonal antibody was generated against recombinant SLA-p35, a truncated recombinant SLA-reactive polypeptide. With a positive patient serum, immune affinity chromatography was performed on the 52 kD-SLA main antigenic determinant pre-enriched by ion exchange chromatography. By mass spectrometry, the 52 kD-SLA/LP/tRNP ((Ser)Sec) autoantigen was unambiguously identified in the purification product. The identity of the recombinant SLA-p35 and its human homologue was further confirmed by a specific signal of the anti SLA-p35 monoclonal antibody with purified human SLA/LP/tRNP((Ser)Sec). The 48 kD-SLA species frequently comigrating in SLA-immunoblotting however was not identified by either approach. We conclude that the native counterpart of recombinant tRNP((Ser)(Sec)) indeed is detectable with a molecular weight of 52 kD in soluble liver extract of human cells as the major antigenic component of SLA/LP/tRNP((Ser)Sec).

Open labeled, uncontrolled pharmacokinetic study of a single intramuscular hCG dose in healthy male volunteers

The current study was designed to compare blood and cerebrospinal fluid (CSF) pharmacokinetic characteristics of two forms of human chorionic gonadotropin (hCG): Pregnyl(R), derived from human urine, and Ovitrelle(R) a recombinant form. Two separate groups, each with six older male human subjects, were dosed with either form of the drug at 10,000 IU intramuscularly (IM), and followed over a 36-hour period. No significant difference in the serum level of hCG was observed for either preparation of hCG (Peak serum conc.: 316 +/- 53 vs. 270 +/- 60 at 12 hours, 311 +/- 38 vs. 321 +/- 60 IU/l at 24 hours; AUC: 10,053 +/- 1,268 vs. 8,793 +/- 1,768, Pregnyl and Ovitrelle, mean +/- SD, respectively). Additionally, both forms of circulating hCG distributed to the central nervous system (CNS) as manifest by an increased number of subjects whose CSF samples showed detectable levels of hCG in their CSF over a 36-hour period. Similarly, there was no significant difference between the two forms when distribution to the CSF was compared at 36 hours (2.0 and 1.2 IU/l; range 1.9 - 2.1 and 1 - 1.4 IU/l for Pregnyl and Ovitrelle, resp.). This preliminary study in normal human volunteers suggests that the two forms of hCG tested, Ovitrelle(R) and Pregnyl(R), when administered IM, distribute in a similar fashion into the circulation and CSF. Consequently, we conclude that these two drugs demonstrate no statistical significant difference with respect to the CSF.

IL-7 administration drives T cell-cycle entry and expansion in HIV-1 infection

Interleukin 7 (IL-7) is a common gamma chain receptor cytokine implicated in thymopoiesis and in peripheral expansion and survival of T lymphocytes. The safety and activity of recombinant human IL-7 (rhIL-7) administration were therefore examined in HIV-infected persons. In this prospective randomized placebo-controlled study, a single subcutaneous dose of rhIL-7 was well tolerated with biologic activity demonstrable at 3 microg/kg and a maximum tolerated dose of 30 microg/kg. Injection site reactions and transient elevations of liver function tests were the most notable side effects. Transient increases in plasma HIV-RNA levels were observed in 6 of 11 IL-7-treated patients. Recombinant hIL-7 induced CD4 and CD8 T cells to enter cell cycle; cell-cycle entry was also confirmed in antigen-specific CD8 T cells. Administration of rhIL-7 led to transient down-regulation of the IL-7 receptor alpha chain (CD127) in both CD4(+) and CD8(+) T cells. Single-dose rhIL-7 increased the numbers of circulating CD4(+) and CD8(+) T cells, predominantly of central memory phenotype. The frequency of CD4(+) T cells with a regulatory T-cell phenotype (CD25(high) CD127(low)) did not change after rhIL-7 administration. Thus, rhIL-7 has a biologic and toxicity profile suggesting a potential for therapeutic trials in HIV infection and other settings of lymphopenia. This clinical trial has been registered at http://www.clinicaltrials.gov under NCT0099671.

Influence of cardiopulmonary bypass on the interaction of recombinant factor VIIa with activated platelets

Recombinant factor VIIa (rFVIIa) interacts preferentially with coated platelets characterized by a high exposure of phosphatidyl serine (PS), FV, FVIII, FIX, and FX binding, and fibrinogen. Cardiopulmonary bypass (CPB) is known to impair platelet function. In this study, the influence of CPB on formation of coated platelets and the interaction of rFVIIa with the platelets were studied. Blood was either exposed to a closed CPB circuit or obtained from patients undergoing CPB-assisted cardiac surgery, and platelets were analyzed by flow cytometry with and without dual agonist stimulation with thrombin and a GPVI collagen receptor agonist known to induce coated platelet formation. Platelets circulated within a closed CPB circuit did not spontaneously form coated platelets. Dual agonists stimulation caused formation of coated platelets at a reduced level compared to pre-CPB level (51 +/- 21% vs. 80 +/- 17% before CPB, p < .001). The rFVIIa interaction with the coated platelets was not impaired after CPB. Platelets isolated from patients undergoing CPB-assisted cardiac surgery also formed coated platelets only after dual agonist stimulation but to the same level as before surgery (76 +/- 8% vs. 83 +/- 14% before surgery, p = .17, n = 10). rFVIIa interaction with the coated platelets was not impaired after surgery. No spontaneous rFVIIa-binding platelets were found. The data indicate that CPB exposure in vivo does not compromise the platelet-dependent effects of rFVIIa either by spontaneous formation of coated platelets, thereby limiting the risk of systemic coagulation, or by impairing rFVIIa interaction with the agonist-induced coated platelets, thereby retaining the hemostatic potential of rFVIIa after CPB.

[Pharmacokinetics of rhGH decorated by polyethylene glycol in rat in vivo]

To study the pharmacokinetics of rhGH decorated by polyethylene glycol (PEG-rhGH) after sc administration in rat, serum PEG-rhGH concentrations were measured by 125I labeled method after sc in rat, the pharmacokinetic model and parameters were fitted and calculated by the 3P97 program. After sc injection at doses of 150, 300, and 600 microg x kg(-1) in rat, the serum PEG-rhGH concentration-time curves were fitted to a one-compartment model. The rhGH decorated by polyethylene glycol could prolong the action duration of rhGH in vivo, and reach the goal of long-action.

An analytical strategy for identification of a somatotropin-like bioactive peptide by ion trap liquid chromatography/electrospray ionization tandem mass spectrometry after immuno-affinity purification from buffalo serum

The use of growth hormones, such as native and recombinant somatotropins, is forbidden in the European Union (EU), but is legal in the USA. The misuse of recombinant bovine somatotropin in Italy is suspected for enhancing milk production, thanks to its availability on the illegal market. A synthetic bioactive peptide of 27 amino acids derived from bovine somatotropin was successfully tested in France and in southern Italy for scientific purposes, to stimulate milk production, both in cows and buffaloes. This somatotropin-like peptide (PEP-ST), suspected for illegal use in southern Italy, was synthesized by linking the 104-113 sequence of bovine somatotropin to the 323-339 sequence of ovalbumin. Herein, a method for detection and identification of the PEP-ST in buffalo serum is described; our strategy was based on the production of IgG anti-PEP-ST, used to synthesize an immuno-affinity column for peptide purification from buffalo serum, prior to analysis by ion trap liquid chromatography/electrospray ionization tandem mass spectrometry (LC/ESI-MS/MS). The immuno-affinity column was successfully used to purify in a single step the bioactive PEP-ST from buffalo serum samples spiked at 20, 50 and 200 microg/mL for confirmatory analysis. Ion trap LC/ESI-MS/MS identification was based on detection of a multi-charged molecular ion and its characteristic fragmentation pattern. No significant matrix interference was observed, accounting for method specificity. We consider this strategy to be a basic approach that could be improved in the perspective of the official control of illegal use of somatotropin and somatotropin-like compounds in buffalo breeding.

Determining the cut-off value of pro-gastrin releasing peptide (ProGRP) in lung cancer according to population characteristics

The standardisation process consisted of determining tumour marker levels in all relevant population groups which are connected with the biology of the marker in normal and tumourous cells. This makes clinical application possible. ProGRP serum levels were measured in 273 healthy subjects, 176 patients with benign diseases and tumours, 200 with small cell lung cancer (SCLC), 294 with non-small cell lung cancer (NSCLC), 21 with carcinoid tumour, 93 with undifferentiated lung cancer, 35 with mixed SCLC-NSCLC, and 189 with other malignancies. ProGRP levels in patients with SCLC and SCLC-NSCLC were significantly higher than in all the other groups (p = 5.4 x 10(-3)). Moreover, in SCLC patients ProGRP levels significantly correlate with the extent of the disease and the patients' smoking habit. The cut-off level of ProGRP for SCLC is 65.89 pg/mL in the Croatian population. It is based on 96.8% specificity in benign diseases which cause problems in differential diagnosis. The sensitivity of ProGRP was 85% at the time of SCLC diagnosis.

Cardiac manifestations of GH deficiency after treatment for acromegaly: a comparison to patients with biochemical remission and controls

OBJECTIVE

Both GH excess and GH deficiency (GHD) lead to specific cardiac pathology. The aim of this study was to evaluate cardiac morphology and function in patients with GHD after treatment for acromegaly.

DESIGN

Cross-sectional study.

PATIENTS AND METHODS

Cardiac parameters were studied by conventional two-dimensional echocardiography and tissue Doppler imaging in 53 patients with acromegaly (16 patients with GHD, 20 patients with biochemical remission, and 17 patients with active disease). Patients with GHD were also compared with age- and gender-matched controls.

RESULTS

Left ventricular (LV) dimensions, wall thickness, and mass did not differ between the three groups, or between the patients with GHD and healthy controls. Systolic function, assessed by LV ejection fraction, tended to be lower in patients with GHD compared with patients with biochemical remission (65.9+/-7.3% vs 72.4+/-8.5%, P=0.070), but was higher when compared with active acromegaly (58.8+/-9.3%, P=0.047). No differences were found with healthy controls. Diastolic function, measured with early diastolic velocity (E'), was lower in patients with GHD when compared with both patients with biochemical remission (6.0+/-2.1 cm/s vs 8.3+/-1.5 cm/s, P=0.005) and healthy controls (8.1+/-1.9 cm/s, P=0.006).

CONCLUSION

GHD after acromegaly results in a specific decrease in diastolic function compared with patients with biochemical remission of acromegaly and healthy controls. In addition, systolic function tends to be decreased in patients with GHD compared with patients with biochemical remission, but was higher than that in patients with active acromegaly.

[Case of anti P/Q type VGCC antibody positive small lung cell carcinoma that occured with subacute cerebellar degeneration, Lambert-Eaton myasthenic syndrome, and brainstem encephalitis]

A 62-year-old man was admitted to our hospital because of rapidly progressive dysarthria, truncal ataxia, and gait disturbance. High titers of the ProGRP and anti-P/Q-type VGCC antibody were detected in the serum. High accumulation of [18F] was detected at the hilus of the left lung on [18F]-FDG-PET scan. A high-frequency repetitive stimulation test of the median nerve yielded an incremental response. On the basis of these findings, a diagnosis of paraneoplastic cerebellar degeneration (PCD) and Lambert-Eaton myasthenic syndrome (LEMS) associated with small cell lung carcinoma (SCLC) was diagnosed. After intravenous immunoglobulin therapy (IVIg), methylprednisolone (m-PSL) pulse therapy, and other multidisciplinary concurrent treatments, a partial regression of the SCLC and a significant improvement in neurological symptoms were observed. However, ataxia relapsed and brainstem encephalitis developed 6 months later. A marginal improvement in neurological symptoms was observed with IVIg, m-PSL pulse therapy, and intravenous cyclophosphamide pulse therapy (IVCY). SCLC also recurred later. We hypothesized that VGCC of the brainstem was damaged by anti-P/Q-type VGCC antibody.

Estradiol supplementation in postmenopausal women attenuates suppression of pulsatile growth hormone secretion by recombinant human insulin-like growth factor type I

BACKGROUND

Why pulsatile GH secretion declines in estrogen-deficient postmenopausal individuals remains unknown. One possibility is that estrogen not only enhances stimulation by secretagogues but also attenuates negative feedback by systemic IGF-I. SITE: The study took place at an academic medical center.

SUBJECTS

Subjects were healthy postmenopausal women (n=25).

METHODS

The study included randomized assignment to estradiol (n=13) or placebo (n=12) administration for 16 d and randomly ordered administration of 0, 1.0, 1.5, and 2.0 mg/m2 recombinant human IGF-I sc on separate days fasting.

ANALYSIS

Deconvolution analysis of pulsatile and basal GH secretion and approximate entropy (pattern-regularity) analysis were done to quantify feedback effects of IGF-I.

OUTCOMES

Recombinant human IGF-I injections increased mean and peak serum IGF-I concentrations dose dependently (P<0.001) and suppressed mean GH concentrations (P<0.001), pulsatile GH secretion (P=0.001), and approximate entropy (P<0.001). Decreased GH secretion was due to reduced secretory-burst mass (P=0.005) and frequency (P<0.001) but not basal GH release (P=0.52). Estradiol supplementation lowered endogenous, but did not alter infused, IGF-I concentrations while elevating mean GH concentrations (P=0.012) and stimulating pulsatile (P=0.008) and basal (P<0.001) GH secretion. Estrogen attenuated IGF-I's inhibition of pulsatile GH secretion (P=0.042) but was unable to restore physiological GH pulse frequency or normalize approximate entropy.

CONCLUSION

Short-term estrogen replacement in postmenopausal women selectively mutes IGF-I-mediated feedback on pulsatile GH secretion. Disinhibition of negative feedback thus confers a novel mechanism by which estrogen may obviate hyposomatotropism.

Direct determination of recombinant bovine somatotropin in plasma from a treated goat by liquid chromatography/high-resolution mass spectrometry

Recombinant bovine somatotropin (rbST) is used in dairy cattle to enhance milk production. Despite the ban on this hormone in some countries, especially in Europe, there is so far no method available for the direct detection of rbST either in milk or in plasma. An analytical strategy has been developed to analyze rbST in plasma, including a purification procedure based on a precipitation with ammonium sulphate, followed by a solid-phase extraction (SPE)-based clean-up on C4 sorbent and precipitation with cold methanol. The hormone was then digested with trypsin and analyzed by liquid chromatography/high-resolution mass spectrometry (LC/HRMSn) on a linear ion trap coupled with an Orbitrap. The tryptic N-terminal peptide, specific to the difference between the endogenous and recombinant form of the somatotropin, was fragmented and product ions were analyzed at high mass resolution. Applying this approach to goat plasma allowed the direct detection of 10 ng mL(-1) of rbST in fortified samples. It also showed the presence of rbST in plasma collected from a goat treated with the hormone, even 2 days after administration. These results are of a great interest in the field of somatotropin control and undoubtedly constitute a first step in the development of a method for the detection of rbST not only in bovine plasma, but also in other biological matrices such as milk.

[Atypical pulmonary carcinoid tumor with abnormal elevation of serum gastrin-releasing peptide precursor: report of a case]

We report a rare case of atypical pulmonary carcinoid tumor accompanied by elevation of serum gastrin-releasing peptide precursor (ProGRP). A 55-year-old male presented to our hospital with a history of bloody sputum. The level of serum ProGRP was elevated to 781 pg/ml (normal < 46 pg/ml). Chest computed tomography (CT) revealed a solitary pulmonary tumor in the left lower lobe with sub-carinal lymph node enlargement. Transbronchial lung biopsy showed a pulmonary carcinoid, therefore left lower lobectomy with mediastinal lymph node dissection was performed. ProGRP decreased to normal level 1 month after operation. Histopathological diagnosis showed an atypical pulmonary carcinoid tumor.

Evolution of ADAMTS13 antibodies in a fatal case of thrombotic thrombocytopenic purpura

In a patient with fatal thrombotic thrombocytopenic purpura, the inhibitory activity of antibodies against ADAMTS13 rapidly escalated to extremely high levels despite daily plasma exchange and corticosteroid therapy. This increase was found to be because of a combination of higher antibody concentration and potency. Furthermore, during her course of the disease, the percentage of IgG(1) antibody progressively decreased whereas that of IgG(2) antibody increased, suggesting Th1-type cytokine response. These changes suggest that the course of TTP may be exacerbated by complex immune reactions. Further characterization of the factors contributing to this exacerbation may have important pathogenetic and therapeutic implications.

Elimination kinetic of recombinant somatotropin in bovine

Bovine somatotropin (bST), also called growth hormone is a protein hormone produced by the pituitary gland and responsible directly or indirectly for various effects on growth, development and reproductive functions. Its recombinant bovine somatotropin form (rbST) is used in dairy cattle to enhance milk production. Even if the effects of treatment with rbST have been largely studied, until now analytical methods able to detect rbST were limited to immunoassays, which suffer from the impossibility to distinguish between the endogenous and the recombinant form. In this study, a sample preparation procedure based on different precipitation steps, extraction on solid phase and enzymatic digestion was used to purify rbST from serum. The detection was performed by liquid chromatography coupled to tandem mass spectrometry in positive electrospray ionization mode (LC-ESI(+)-MS/MS) allowing the unambiguous identification and quantification of rbST in serum. Samples collected from a cow treated with recombinant bovine somatotropin were analysed and for the first time, the elimination kinetic specific to recombinant somatotropin has been characterized in serum. Detection of rbST was possible from 4h 30min to 4 days after administration and concentration was found up to 10ngmL(-1) during the kinetic.

A novel insulin formulation with a more rapid onset of action

AIMS/HYPOTHESIS

This study evaluates the pharmacodynamic and pharmacokinetic properties of the novel ultra-fast insulin product VIAject, a formulation of human soluble insulin and generally recognised as safe ingredients designed to increase the rate of absorption.

METHODS

We performed five euglycaemic glucose clamps (Biostator; target blood glucose 5 mmol/l) in ten healthy volunteers. Using a crossover design with a fixed treatment order, 12 IU human soluble insulin, 12 U insulin lispro and 12 IU ultra-fast insulin were injected s.c. in the abdominal region on three study days. On the other two study days, 6 and 3 IU ultra-fast insulin were injected.

RESULTS

Subcutaneous injection of 12 IU ultra-fast insulin resulted in a time-action profile characterised by an even more rapid onset of action and maximal metabolic activity than insulin lispro: time to early half-maximal activity was 33 +/- 17 min (mean +/- SD) vs insulin lispro 51 +/- 13 min vs human soluble insulin 66 +/- 15 min (p < 0.05 ultra-fast insulin<insulin lispro<human soluble insulin); time to maximal activity was 136 +/- 56 min vs insulin lispro 152 +/- 30 min vs human soluble insulin 193 +/- 57 min (p < 0.05 ultra-fast insulin and insulin lispro<human soluble insulin). The metabolic activity in the first 2 h after injection was higher with ultra-fast insulin and insulin lispro than with human soluble insulin (AUC glucose infusion rate [GIR] 0-120 min: 915 +/- 301 and 781 +/- 174 vs 580 +/- 164 mg/kg; p < 0.05). A clear dose-response relationship was observed with the three doses of ultra-fast insulin: AUCGIR 0-120 min 12 IU 915 +/- 301 vs 6 IU 718 +/- 255 vs 3 IU 524 +/- 262 mg/kg (p < 0.05). The pharmacokinetic data confirmed the pharmacodynamic results.

CONCLUSIONS/INTERPRETATION

This study shows that the onset of action of VIAject is faster than that of human soluble insulin and insulin lispro.

Growth hormone responsiveness: peak stimulated growth hormone levels and other variables in idiopathic short stature (ISS): data from the National Cooperative Growth Study

HYPOTHESIS

In children with idiopathic short stature (ISS), growth hormone (GH) response to a provocative test will be inversely related to the first year response to hGH and be a variable accounting for a degree of responsiveness.

BACKGROUND

Because high levels of GH are a characteristic of GH insensitivity, such as in Laron syndrome, it is possible that a high stimulated GH is associated with a lower first year height velocity among children diagnosed as having ISS.

METHODS

We examined the relationship between the peak stimulated GH levels in 3 ISS groups; GH >10 -<25, 25-40, and >40 ng/mL and the first year growth response to rhGH therapy. We also looked at 8 other predictor variables (age, sex, height SDS, height age, body mass index (BMI), bone age, dose, and SDS deficit from target parental height. Multiple regression analysis with the first year height as the dependent variable and peak stimulated GH was the primary endpoint. The predictive value of adding each of the other variables was then assessed.

RESULTS

Mean change in height velocity was similar among the three groups, with a maximum difference among the groups of 0.6 cm/yr. There was a small but statistically significant correlation (r=-0.12) between the stimulated GH and first year height velocity.

CONCLUSIONS

The small correlation between first year growth response and peak GH is not clinically relevant in defining GH resistance. No cut off level by peak GH could be determined to enhance the usefulness of this measure to predict response. Baseline age was the only clinically significant predictor, R-squared, 6.4%. All other variables contributed less than an additional 2% to the R-squared.