Powder plasma spheroidization treatment and the characterization of microstructure and mechanical properties of SS 316L powder and L-PBF builds

A plasma spheroidization treatment was applied to stock stainless steel 316L powder for additive manufacturing. The normal and treated powders were compared both in the powder state as well as in the resulting laser powder bed fusion (L-PBF) builds. The plasma spheroidization process slightly increased treated powder aspect ratio and sphericity and shifted the size distribution to larger diameters relative to the normal powder. The normal powder was austenitic in nature whereas the plasma spheroidization process introduced a small fraction (∼3.5 vol %) of ferrite in the treated powder. Ferrite in the powder was not retained in the printed samples and was not shown to negatively affect the build quality. Porosity areal fraction was generally smaller in the treated powder builds. The normal powder builds had a 6% higher yield strength than treated, however the scatter was significantly larger in the 45° and horizontal orientations compared to the treated powder builds.

P-246 A novel non-invasive tool for oocyte selection using gene expression and artificial intelligence

Study question

Is it possible to predict top quality embryos through gene expression analysis of cumulus cells and artificial intelligence before fertilization?

Summary answer

The artificial inteligence based tool OsteraTest is able to predict the ability of the oocyte to develop into a top quality blastocyst with 86% accuracy.

What is known already

Proper oocyte selection is an important bottleneck for In Vitro Fertilization (IVF) success. Nowadays, oocyte selection relies mainly in morphological analyses, which is not an unbiased method and may fail to reveal the real competence status of gametes. Cumulus oophorus cells (CC) are somatic cells that surround the oocyte at the antral follicle. It is directly involved in oocyte maturation and development, and thus is a valuable non-invasive source of biological information regarding the oocyte’s health. Artificial intelligence can be used to identify key biological processes and markers of interest through machine learning methods and could thus be applied.

Study design, size, duration

This is a prospective study that included data from 80 CC samples retrieved from publicly available microarray data (GSE27377) in the algorithm construction phase and 65 CC samples from each oocyte of 26 patients submitted to Intracytoplasmic Sperm Injection (ICSI) in validation phase. Samples were divided in two groups: CCs from oocytes that developed into top quality blastocysts in day 5 after ICSI and CCs from oocytes that presented arrested development.

Participants/materials, setting, methods

Samples were submitted to real time quantitative PCR with 25 target genes. Afterwards, gene expression levels for each gene and sample were submitted to the final algorithm, that was computed into a software, the OsteraTest, in a double-blind approach. The software indicated the development potential of each oocyte and this ranking was compared to the embryologist’s day 5 blastocyst classification according to Gardner.

Main results and the role of chance

The bioinformatic approach implemented resulted in the OsteraTest, composed of 8 machine learning models using a 25-gene network that altogether can predict oocyte quality, thus representing a very complex assembly. The software presented more than 86% accuracy in predicting the oocytes developmental capacity into a top-quality day 5 blastocyst. Top quality blastocysts present over 80% chance of resulting in a healthy pregnancy and live birth, and so this approach could be further used as a pregnancy potential predictor after a prospective study is conducted, analyzing CCs from oocytes that were further fertilized, developed into blastocysts and transferred in single embryo transfers. This tool can contribute greatly to improve success rates in IVF procedures and to assess egg quality in egg freezing procedures, providing information about the gametes potential even years before its use.

Limitations, reasons for caution

A large-scale, prospective, randomized study is necessary for further validation of these findings and to confirm the validity of the OsteraTest in the clinical environment. Such study is now being conducted in our lab.

Wider implications of the findings

The OsteraTest proved to be a valuable non-invasive tool to predict embryo formation and oocyte capacity even before fertilization.It can enable the clinics to anticipate successful treatments and provide a predictive report for oocyte freezing patients.

Trial registration number

#68081017.2.0000.5347

Prevalence of resistance-associated substitutions and retreatment of patients failing a glecaprevir/pibrentasvir regimen

OBJECTIVES

To investigate resistance-associated substitutions (RASs) as well as retreatment efficacies in a large cohort of European patients with failure of glecaprevir/pibrentasvir.

METHODS

Patients were identified from three European Resistance Reference centres in Spain, Italy and Germany. Sequencing of NS3, NS5A and NS5B was conducted and substitutions associated with resistance to direct antiviral agents were analysed. Clinical and virological parameters were documented retrospectively and retreatment efficacies were evaluated.

RESULTS

We evaluated 90 glecaprevir/pibrentasvir failures [3a (n = 36), 1a (n = 23), 2a/2c (n = 20), 1b (n = 10) and 4d (n = 1)]. Ten patients were cirrhotic, two had previous exposure to PEG-interferon and seven were coinfected with HIV; 80 had been treated for 8 weeks. Overall, 31 patients (34.4%) failed glecaprevir/pibrentasvir without any NS3 or NS5A RASs, 62.4% (53/85) showed RASs in NS5A, 15.6% (13/83) in NS3 and 10% (9/90) in both NS5A and NS3. Infection with HCV genotypes 1a and 3a was associated with a higher prevalence of NS5A RASs. Patients harbouring two (n = 34) or more (n = 8) RASs in NS5A were frequent. Retreatment was initiated in 56 patients, almost all (n = 52) with sofosbuvir/velpatasvir/voxilaprevir. The overall sustained virological response rate was 97.8% in patients with end-of-follow-up data available.

CONCLUSIONS

One-third of patients failed glecaprevir/pibrentasvir without resistance. RASs in NS5A were more prevalent than in NS3 and were frequently observed as dual and triple combination patterns, with a high impact on NS5A inhibitor activity, particularly in genotypes 1a and 3a. Retreatment of glecaprevir/pibrentasvir failures with sofosbuvir/velpatasvir/voxilaprevir achieved viral suppression across all genotypes.

Efficacy of Retreatment After Failed Direct-acting Antiviral Therapy in Patients With HCV Genotype 1-3 Infections

Hepatitis C virus infection is causing chronic liver disease, cirrhosis, and hepatocellular carcinoma. By combining direct-acting antivirals (DAAs), high sustained virologic response rates (SVRs) can be achieved. Resistance-associated substitutions (RASs) are commonly observed after DAA failure, and especially nonstructural protein 5A (NS5A) RASs may impact retreatment options.^1-3 Data on retreatment of DAA failure patients using first-generation DAAs are limited.^4-7 Recently, a second-generation protease- and NS5A-inhibitor plus sofosbuvir (voxilaprevir/velpatasvir/sofosbuvir [VOX/VEL/SOF]) was approved for retreatment after DAA failure.⁸ However, this and other second-generation regimens are not available in many resource-limited countries or are not reimbursed by regular insurance, and recommendations regarding the selection of retreatment regimens using first-generation DAAs are very important. This study aimed to analyze patients who were re-treated with first-generation DAAs after failure of a DAA combination therapy.

Real-world use, effectiveness and safety of anti-viral treatment in chronic hepatitis C genotype 3 infection

BACKGROUND

Treatment of chronic hepatitis C genotype 3 (GT3) is more challenging compared with other genotypes. Since 2014, several new treatment regimens have been approved but sometimes based on limited data.

AIM

To validate the use, effectiveness and safety of anti-viral treatment in chronic hepatitis C genotype 3 infection under real-word conditions.

METHODS

The German Hepatitis C-Registry is a large national non-interventional real-world study for patients with chronic hepatitis C. A total of 1322 GT3 patients were enrolled (211 untreated and 1111 treated patients).

RESULTS

Between February 2014 and September 2015, five different treatment strategies have been used (PegIFN+RBV, PegIFN+RBV+SOF, SOF+RBV, DCV+SOF±RBV, LDV/SOF±RBV). Treatment uptake and use of treatment concepts changed markedly and rapidly during the study influenced by new approvals, guideline recommendations, and label updates. PegIFN-based therapies constantly declined while DCV-based therapies increased with one interruption after the approval of LDV/SOF, which was frequently used until new guidelines recommended not using this combination for GT3. Per-protocol SVR ranged from 80.9% in the PegIFN+RBV group to 96.1% in PegIFN+RBV+SOF treated patients. Treatment-experienced patients with cirrhosis showed a suboptimal SVR of 68% for SOF+RBV but a high SVR of 90-95% for DCV+SOF±RBV. The safety analysis showed more adverse events and a stronger decline of haemoglobin for RBV containing regimens.

CONCLUSIONS

Real-world data can validate the effectiveness and safety for treatment regimens that had previously been approved with limited data, in particular for specific subgroups of patients. The present study demonstrates how rapid new scientific data, new treatment guidelines, new drug approvals and label changes are implemented into routine clinical practice today.

The Influence of Probiotics on Reproductive Parameters of Sows and Health of Their Sucklings

Thirtytwo sows were included in the trial. They were divided into the experimental group (n = 16) and a control group (n = 16). The experimental group received 1.28 × 106 Bacillus subtilis and Bacillus licheniformis per gram of feed (400 ppm BioPlus 2B, Chr. Hansen, Denmark). The trial started 2 weeks before farrowing and lasted until weaning. No significant differences were revealed in the number of piglets born alive, stillborn or the number of weaned pigs between the two groups of sows. The wean-to-first service interval was not significantly different between the groups, but sows in the experimental group had earlier first services. The conception rate did not differ. Sows in the experimental group suffered from postpartum dysgalactia syndrome (PDS) less than sows in the control group. The suckling piglets in the experimental group of sows reached better weight on day 14 of the trial and this state persisted up to the end of the experiment. The differences in the weights of the experimental group and the control group were significant at the end of the trial (P < 0.01). The experimental piglets had significantly lower incidence of diarrhoea than those in the control group (P < 0.05).

Dietary management of urea cycle disorders: European practice

BACKGROUND

There is no published data comparing dietary management of urea cycle disorders (UCD) in different countries.

METHODS

Cross-sectional data from 41 European Inherited Metabolic Disorder (IMD) centres (17 UK, 6 France, 5 Germany, 4 Belgium, 4 Portugal, 2 Netherlands, 1 Denmark, 1 Italy, 1 Sweden) was collected by questionnaire describing management of patients with UCD on prescribed protein restricted diets.

RESULTS

Data for 464 patients: N-acetylglutamate synthase (NAGS) deficiency, n=10; carbamoyl phosphate synthetase (CPS1) deficiency, n=29; ornithine transcarbamoylase (OTC) deficiency, n=214; citrullinaemia, n=108; argininosuccinic aciduria (ASA), n=80; arginase deficiency, n=23 was reported. The majority of patients (70%; n=327) were aged 0-16y and 30% (n=137) >16y. Prescribed median protein intake/kg body weight decreased with age with little variation between disorders. The UK tended to give more total protein than other European countries particularly in infancy. Supplements of essential amino acids (EAA) were prescribed for 38% [n=174] of the patients overall, but were given more commonly in arginase deficiency (74%), CPS (48%) and citrullinaemia (46%). Patients in Germany (64%), Portugal (67%) and Sweden (100%) were the most frequent users of EAA. Only 18% [n=84] of patients were prescribed tube feeds, most commonly for CPS (41%); and 21% [n=97] were prescribed oral energy supplements.

CONCLUSIONS

Dietary treatment for UCD varies significantly between different conditions, and between and within European IMD centres. Further studies examining the outcome of treatment compared with the type of dietary therapy and nutritional support received are required.

Dietary practices in pyridoxine non-responsive homocystinuria: a European survey

BACKGROUND

Within Europe, the management of pyridoxine (B6) non-responsive homocystinuria (HCU) may vary but there is limited knowledge about treatment practice.

AIM

A comparison of dietetic management practices of patients with B6 non-responsive HCU in European centres.

METHODS

A cross-sectional audit by questionnaire was completed by 29 inherited metabolic disorder (IMD) centres: (14 UK, 5 Germany, 3 Netherlands, 2 Switzerland, 2 Portugal, 1 France, 1 Norway, 1 Belgium).

RESULTS

181 patients (73% >16 years of age) with HCU were identified. The majority (66%; n=119) were on dietary treatment (1-10 years, 90%; 11-16 years, 82%; and >16 years, 58%) with or without betaine and 34% (n=62) were on betaine alone. The median natural protein intake (g/day) on diet only was, by age: 1-10 years, 12 g; 11-16 years, 11 g; and >16 years, 45 g. With diet and betaine, median natural protein intake (g/day) by age was: 1-10 years, 13 g; 11-16 years, 20 g; and >16 years, 38 g. Fifty-two percent (n=15) of centres allocated natural protein by calculating methionine rather than a protein exchange system. A methionine-free l-amino acid supplement was prescribed for 86% of diet treated patients. Fifty-two percent of centres recommended cystine supplements for low plasma concentrations. Target treatment concentrations for homocystine/homocysteine (free/total) and frequency of biochemical monitoring varied.

CONCLUSION

In B6 non-responsive HCU the prescription of dietary restriction by IMD centres declined with age, potentially associated with poor adherence in older patients. Inconsistencies in biochemical monitoring and treatment indicate the need for international consensus guidelines.

C-reactive protein, an indicator for maintained response or remission to infliximab in patients with Crohn's disease: a post-hoc analysis from ACCENT I

BACKGROUND

Secondary loss of response to anti-TNF-α therapy is observed in Crohn's disease patients.

AIM

Serum C-reactive protein (CRP) levels at baseline and after infliximab induction therapy at week 14 were assessed as predictors for maintained response or remission through 54 weeks of treatment in patients with Crohn's disease who responded to induction therapy.

METHODS

ACCENT I was a multicenter, randomised, placebo-controlled study. Patients who received infliximab induction (weeks 0, 2 and 6) and maintenance (5 or 10 mg/kg every 8 weeks beginning at week 14) therapy were considered. Patients in clinical response or remission to induction therapy at week 14 (n = 212 or n = 138 respectively) were analysed. Associations between CRP levels (cut-off points 0.5-3.0 mg/dL), baseline disease variables and maintained clinical response or remission during maintenance therapy were assessed.

RESULTS

A significant association was observed between baseline CRP levels and maintained remission. Forty-five percent of patients with baseline CRP ≥ 0.7 mg/dL vs. 22.0% with CRP < 0.7 mg/dL maintained remission (P = 0.012). CRP normalisation during infliximab treatment (decrease from 0.5 mg/dL at baseline to < 0.5 mg/dL at week 14) resulted in higher probability of maintained response (P < 0.001) or remission (P = 0.052). At week 14 low CRP levels were associated with maintained response (56.6% of patients with CRP < 0.5 mg/dL vs. 37.2% with higher CRP, P = 0.005). No optimal predictive CRP cut-off point was observed.

CONCLUSIONS

High baseline CRP levels increased the likelihood of maintained remission. Normalised CRP levels at week 14 increased the likelihood of maintained response or remission during 1 year of infliximab maintenance therapy (

CLINICAL TRIAL

NCT00207662).

Estimating the likelihood of sustained virological response in chronic hepatitis C therapy

The likelihood of a sustained virological response (SVR) is the most important factor for physicians and patients in the decision to initiate and continue therapy for chronic hepatitis C (CHC) infection. This study identified predictive factors for SVR with peginterferon plus ribavirin (RBV) in patients with CHC treated under 'real-life' conditions. The study cohort consisted of patients from a large, retrospective German multicentre, observational study who had been treated with peginterferon alfa-2a plus RBV or peginterferon alfa-2b plus RBV between the years 2000 and 2007. To ensure comparability regarding peginterferon therapies, patients were analysed in pairs matched by several baseline variables. Univariate and multivariate logistic regression analyses were used to determine the effect of nonmatched baseline variables and treatment modality on SVR. Among 2378 patients (1189 matched pairs), SVR rates were 57.9% overall, 46.5% in HCV genotype 1/4-infected patients and 77.3% in genotype 2/3-infected patients. In multivariate logistic regression analysis, positive predictors of SVR were HCV genotype 2 infection, HCV genotype 3 infection, low baseline viral load and treatment with peginterferon alfa-2a. Negative predictors of SVR were higher age (≥40 years), elevated baseline gamma-glutamyl transpeptidase (GGT) and low baseline platelet count (<150,000/μL). Among patients treated with peginterferon plus RBV in routine clinical practice, genotype, baseline viral load, age, GGT level and platelet levels all predict the likelihood of treatment success. In patients matched by baseline characteristics, treatment with peginterferon alfa-2a may be a positive predictor of SVR when compared to peginterferon alfa-2b.

[kappa-light chain amyloidosis of the liver, a rare cause of liver enzyme elevation]

HISTORY AND ADMISSION FINDINGS

A 69-year-old man was admitted to the department of gastroenterology having for months had persistently elevated liver enzymes after discontinuing systemic antimycotic therapy. He reported loosing five kilogram of body weight in the past six months. No macroscopic or microscopic abnormalities had been found on esophago-gastroduodenoscopy.

INVESTIGATIONS

Congo-red staining of the liver biopsy revealed massive sinusoidal amyloidosis of the liver. Immunoelectrophoresis of the urine and serum, as well as bone marrow biopsy, ruled out multiple myeloma or Waldenström's disease. Immunohistochemical staining identified the amyloid protein as a IgG kappa light chain (KLC). The free light chain (FLC) test confirmed KLC monoclonal gammopathy with an abnormal free kappa to lambda chain (KLLC) ratio.

TREATMENT AND COURSE

Systemic KLC amyloidosis in this patient older than 65 years was given chemotherapy with melaphalan and dexamethasone (M-Dex). After three courses of M-Dex the renal clearance deteriorated and the serum N-terminal probrain natriuretic peptide (T-proBNP) had increased.

COURSE

The patient was included in a phase II clinical trial which evaluates the use of bortezomib in patients with amyloidosis. Normalization of the free KLLC ratio and the NT-proBNP level will serve as important prognostic indicators.

CONCLUSION

KLC amyloidosis is a rare cause of elevated liver enzymes. The nonspecific symptoms often delay the diagnosis. FLC testing is a helpful tool in identifying monoclonal gammopathies, even when immunoelectrophoretic tests are normals.

Safety, tolerability and efficacy of peginterferon alpha-2a and ribavirin in chronic hepatitis C in clinical practice: The German Open Safety Trial

The combination treatment of peginterferon alpha-2a (PEG-IFN alpha-2a; Pegasys) plus ribavirin (RBV) is recommended as a standard care for HCV infections. Side effects and aspects of efficacy and safety have to be balanced. This study evaluates clinical practice data on safety and efficacy of HCV treatment with PEG-IFN in combination with RBV over 24 and 48 weeks. This study was a phase III, multi-centre, open-label study with two treatment groups: PEG-IFN in combination with RBV for 24 or 48 weeks. The allocation to the treatment groups was at the discretion of the investigator; 309 patients entered active treatment: 90 patients received PEG-IFN plus RBV for 24 weeks and 219 patients PEG-IFN plus RBV for 48 weeks. A sustained virological response (SVR) was achieved in 48.9% of all patients. Genotype 1 patients with a 48-week combination treatment achieved an SVR of 39.9%. In the 48-week group a low baseline viral load was associated with a higher SVR rate (47.0% vs. 32.4%). For genotype 2 or 3 patients, the SVR was 67.9%. For these patients there was no relevant difference between patients with low and high viral loads; 97.7% of the patients experienced at least one adverse event. The incidence of serious adverse events was distinctly lower in the 24-week group (4.4% vs. 10.5%). This investigation confirms the well-known risk-benefit ratio found in controlled studies in a clinical practice setting. The safety profile is similar and shows the highest incidence of adverse events in the first 12 weeks of treatment.

Use of a validated quality of life questionnaire to assess sexual function following laparoscopic radical prostatectomy

Wide variations exist in the methods for evaluating potency following radical prostatectomy. We describe our technique of laparoscopic radical prostatectomy (LRP), present our methods for assessing the return of potency following LRP, and discuss the relevant literature. Sexual function was assessed pre- and postoperatively using the Expanded Prostate Cancer Index Composite questionnaire (EPIC). Sexual function subscale scores (SFSS) were reported as a percentage of preoperative baseline sexual function. The EPIC was also used for single-question assessment of successful intercourse. We also reviewed the literature on prospective health-related quality of life results following LRP and open radical retropubic prostatectomy. Only patients reporting preoperative intercourse were analyzed. Of these, 72 and 35% undergoing bilateral and unilateral nerve sparing (NS) reported postoperative intercourse at 12 months (P=0.01). Mean SFSS at 12 months was 61 and 57% of baseline after bilateral and unilateral NS, respectively (P=0.71). Following NS procedures, 74% of patients < or =58 years of age and 41% of patients >58 years of age reported successful intercourse at 12 months (P=0.015). Mean SFSS was 64 and 52% of baseline function (P=0.249) at 12 months for patients < or =58 and >58 years of age, respectively. In patients <58 years of age who underwent bilateral NS surgery, 82% reported intercourse at 12 months. In conclusion, return of sexual function following NS LRP in our experience is comparable to reports from centers of excellence in open prostatectomy. Standardizing data collection using validated quality of life instruments can provide both surgeon and patient with a realistic forecast of relative return to normal sexual function following prostatectomy.

Markov model aided decoding for image transmission using soft-decision-feedback

Soft-decision-feedback MAP decoders are developed for joint source/channel decoding (JSCD) which uses the residual redundancy in two-dimensional sources. The source redundancy is described by a second order Markov model which is made available to the receiver for row-by-row decoding, wherein the output for one row is used to aid the decoding of the next row. Performance can be improved by generalizing so as to increase the vertical depth of the decoder. This is called sheet decoding, and entails generalizing trellis decoding of one-dimensional data to trellis decoding of two-dimensional data (2-D). The proposed soft-decision-feedback sheet decoder is based on the Bahl algorithm, and it is compared to a hard-decision-feedback sheet decoder which is based on the Viterbi algorithm. The method is applied to 3-bit DPCM picture transmission over a binary symmetric channel, and it is found that the soft-decision-feedback decoder with vertical depth V performs approximately as well as the hard-decision-feedback decoder with vertical depth V+1. Because the computational requirement of the decoders depends exponentially on the vertical depth, the soft-decision-feedbark decoder offers significant reduction in complexity. For standard monochrome Lena, at a channel bit error rate of 0.05, the V=1 and V=2 soft-decision-feedback decoder JSCD gains in RSNR are 5.0 and 6.3 dB, respectively.

5'-N-substituted carboxamidoadenosines as agonists for adenosine receptors

Novel as well as known 5'-N-substituted carboxamidoadenosines were prepared via new routes that provided shorter reaction times and good yields. Binding affinities were determined for rat A1 and A2A receptors and human A3 receptors. EC50 values were determined for cyclic AMP production in CHO cells expressing human A2B receptors. On all receptor subtypes relatively small substituents on the carboxamido moiety were optimal. Selectivity for the A3 receptor was found for several analogues (1a, 1d, 1h, and 1k). On A1 receptors a number of compounds, but not 5'-N-ethylcarboxamidoadenosine (NECA, 1b), showed small GTP shifts, which could be indicative of lower intrinsic activities at the A1 receptor. At the A2B receptor, derivatives 1i-k with modified ethyl substituents had reduced activities compared to the A2B reference agonist NECA (1b). Thiocarboxamido derivatives (8b and 8c) displayed considerable although decreased A2B receptor activity. The X-ray structure determination of compound 8b was carried out. Due to intramolecular hydrogen bonding between the carboxamido NH and the purine N3 in the crystal structure, the ribose moiety of this compound is in a syn conformation. However, theoretical calculations support that NECA (1b), and less so 8b, can readily adopt both the syn and the anti conformation, therefore not excluding the proposed anti mode of binding to the receptor.

A novel class of adenosine A3 receptor ligands. 2. Structure affinity profile of a series of isoquinoline and quinazoline compounds

1-Substituted 3-(2-pyridinyl)isoquinolines have been shown to form a novel class of adenosine A3 receptor ligands. In the present study further investigations of this new lead and the structure affinity relationships of this class of compounds are described. First, the influence of an amide group at position 1 of the isoquinoline ring on the adenosine A3 receptor affinity was determined. A carboxamide proved to be a useful spacer between the isoquinoline and a phenyl ring. N-[2-(2-pyridinyl)isoquinolin-4-yl]benzamide (VUF8507, compound 6) had an affinity of 200 nM at the adenosine A3 receptor. Second, we investigated the effects of substitution of the benzamide ring of 6 with a series of mono- and disubstituted N-[3-(2-pyridinyl)isoquinoline]benzamides. The ratio of the tautomers of the benzamides was determined in the solid state and in solution by spectroscopic techniques (IR and NMR). Affinities were determined in radioligand binding assays at rat brain A1 and A2A receptors and at cloned human A3 receptor. The benzamides showed higher adenosine A3 receptor affinity than aliphatic amides. We propose that the adenosine A3 receptor affinity of the different benzamides is related to their presence in either the iminol or amide form. Ligands present in the iminol form showed relatively high adenosine A3 receptor affinity. Finally, we explored the influence of replacement of C4 of the isoquinoline ring by a nitrogen atom. Comparison of isoquinolines with the corresponding quinazolines revealed that both compounds showed similar adenosine A3 receptor affinity. These investigations led to potent and selective human adenosine A3 receptor ligands with affinities in the nanomolar range. The subtype-selective compound 4-methoxy-N-[2-(2-pyridinyl)quinazolin-4-yl]benzamide (VUF8504, 13) with an affinity of 17.0 nM at the human adenosine A3 receptor might become a useful tool in the pharmacological characterization or the investigation of the physiological function of this receptor.

A novel class of adenosine A3 receptor ligands. 1. 3-(2-Pyridinyl)isoquinoline derivatives

A series of 3-(2-pyridinyl)isoquinoline derivatives was synthesized as potential antagonists for the human adenosine A3 receptor by substitution of the 1-position. The compounds were obtained by various synthetic routes from 1-amino-3-(2-pyridinyl)isoquinoline. The affinity was determined in radioligand binding assays for rat brain A1 and A2A receptors and for the cloned human A3 receptor. A structure-activity relationship analysis indicated that a phenyl group when coupled by a spacer allowing conjugation on position 1 of the isoquinoline ring increased the adenosine A3 receptor affinity. In contrast, such a phenyl group directly bound to position 1 of the isoquinoline ring decreased affinity. Since the combination of a phenyl group together with a spacer raised adenosine A3 receptor affinity, various spacers were investigated. VUF8501 (N-[3-(2-pyridinyl)isoquinolin-1-yl]benzamidine (15) showed an affinity at the human adenosine A3 receptor of 740 nM. Substituent effects on the phenyl group were investigated by in vitro evaluation of a series of substituted benzamidines. Electron-donating groups at the para position of the benzamidine ring increased adenosine A3 receptor affinity. These investigations led to VUF8505 (4-methoxy-N-[3-(2-pyridinyl)isoquinolin-1-yl]benzamidine(22)), which is a moderately potent and selective ligand for the human adenosine A3 receptor with an affinity of 310 nM in our test system having negligible affinity for rat A1 and A2A receptors.

A functional screening of adenosine analogues at the adenosine A2B receptor: a search for potent agonists

Various adenosine analogues were tested at the adenosine A2B receptor. Agonist potencies were determined by measuring the cyclic AMP production in Chinese Hamster Ovary cells expressing human A2B receptors. 5'-N-Substituted carboxamidoadenosines were most potent. 5'-N-Ethylcarboxamidoadenosine (NECA) was most active with an EC50 value of 3.1 microM. Other ribose modified derivatives displayed low to negligible activity. Potency was reduced by substitution on the exocyclic amino function (N6) of the purine ring system. The most active N6-substituted derivative N6-methyl-NECA was 5 fold less potent than NECA. C8- and most C2-substituted analogues were virtually inactive. 1-Deaza-analogues had a reduced potency, 3- and 7-deazaanalogues were not active.

Study of the interaction between aryloxypropanolamines and Asn386 in helix VII of the human 5-hydroxytryptamine1A receptor

We studied the stereoselective interaction between aryloxypropanolamines and the human 5-hydroxytryptamine1A (5-HT1A) receptor. R- and S-enantiomers of propranolol, penbutolol, and alprenolol were investigated for their ability to bind to human 5-HT1A wild-type and Asn386Val mutant receptors. Asn386 seemed to act as a chiral discriminator. Although both aryloxypropanol enantiomers displayed lower affinity for the mutant receptors, the affinities for the S-enantiomers were more affected. Receptor affinities of other structurally unrelated 5-HT1A ligands were not decreased by the mutation of Asn386 to valine. In addition, a series of analogues of propranolol with structural variation in the oxypropanolamine moiety was synthesized, and affinities for wild-type and Asn386Val mutant 5-HT1A receptors were determined. Both the hydroxyl and the ether oxygen atoms of the oxypropanol moiety seem to be required for binding at wild-type 5-HT1A receptors. The hydroxyl group of propranolol probably directly interacts with Asn386. The ether oxygen atom may be important for steric reasons but can also be involved in a direct interaction with Asn386. These findings are in agreement with the interactions of aryloxypropanolamines with Asn386 in rat 5-HT1A receptors that we previously proposed. The loss of affinity for propranolol by the Asn386Val mutation could be regained by replacement of the hydroxyl group of the ligand by a methoxy group. This modification of the propranolol structure has no effect on the affinity of both enantiomers for the wild-type 5-HT1A receptor, which provides an alternative hypothesis for the interaction of Asn386 with the oxypropanol oxygen atoms. According to this novel hypothesis, the oxypropanol oxygen atoms may both act as hydrogen bond acceptors from the NH2 group of Asn386.

Subtype-specific differences in the intracellular sorting of G protein-coupled receptors

We have examined the subcellular distribution of three subtypes of adrenergic receptor by immunocytochemical localization of wild-type and epitope-tagged proteins expressed in Cos-7 and K293 cells. Two subtypes (beta 2 and M alpha 2-10H) are localized in the plasma membrane at steady state in untreated cells, while another subtype (M alpha 2-4H) is found both in the plasma membrane and in a population of intracellular vesicles. Within 15 min following the addition of adrenergic agonists, beta 2 and M alpha 2-10H receptors are differentially sorted; beta 2 receptors are selectively internalized to intracellular vesicles, which are distinct from those containing M alpha 2-4H receptors, while M alpha 2-10H receptors remain in the plasma membrane. Subtype-specific sorting suggests a new class of functional properties that may differentiate the signaling and regulation of homologous G protein-coupled receptors.

Analysis of mono-, di- and triglycerides in pharmaceutical excipients by capillary supercritical fluid chromatography

Mono-, di- and triglycerides are important components of oils, fats and other natural products. Since in general fatty acids are mixtures and glycerol can be differently substituted, finger-prints of the composition are suitable for better characterization. Since capillary supercritical fluid chromatography (SFC) employing carbon dioxide as mobile phase is compatible with flame ionization detection, it is possible to analyse many solutes at trace levels. Supercritical carbon dioxide offers higher solute diffusivity compared with the inert carrier gas conventionally used in gas chromatography and has a lower viscosity than the liquid solvents used in HPLC. Thus, glycerides of fatty acids can be separated and eluted at a lower temperature and with shorter analysis time in SFC. In this study the analysis of mono-, di- and triglyceride mixtures in several pharmaceutical excipients is reported using capillary SFC. Quantitative analysis is possible on the basis of a response factor established for each analyte. The accuracy of the method and its advantages are demonstrated.

Cloning of two mouse genes encoding alpha 2-adrenergic receptor subtypes and identification of a single amino acid in the mouse alpha 2-C10 homolog responsible for an interspecies variation in antagonist binding

Molecular cloning and ligand binding studies have shown the alpha 2 class of adrenergic receptor (alpha 2-AR) to be a family of at least three related subtypes in humans. These studies have not, however, identified distinct subtype-specific functions for these receptors in vivo. It should be possible to extend the analysis of alpha 2-AR subtype function to the animal level through the use of experimental mammalian embryology in mice. To begin this process, we have isolated two mouse genomic clones encoding alpha 2-AR subtypes and expressed these genes in COS-7 cells for binding studies. Sequence homology and ligand binding data allow the assignment of one clone (M alpha 2-4H) as the mouse homolog of the human alpha 2-C4 subtype. The other clone (M alpha 2-10H) closely resembles the human alpha 2-C10 subtype in sequence but binds with significantly lower affinity to yohimbine and rauwolscine, members of a distinct class of bulky alpha 2-selective antagonists commonly used to evaluate alpha 2-AR function in vivo. To define the domain(s) responsible for this unusual binding property, we constructed a series of M alpha 2-10H/human alpha 2-C10 chimeric receptors. Analysis of these receptors identified a conservative Cys201 to Ser201 change in the fifth transmembrane domain of M alpha 2-10H as being responsible for the low affinity of the mouse receptor for yohimbine.

Histopathological studies on the local reactions induced by complete Freund's adjuvant (CFA), bacterial lipopolysaccharide (LPS), and synthetic lipopeptide (P3C) conjugates

The inflammatory reactions following subcutaneous application of adjuvants revealed characteristic pathological patterns. The injection of complete Freund's adjuvant (CFA) resulted in the formation of large lipid deposits encircled by an inflammatory reaction and concentrically arranged collagen bundles. Bacterial lipopolysaccharide (LPS) caused granulomatous aggregations of mononuclear cells with thrombotic vessel occlusions. Inoculation of the lipopeptide adjuvants induced accumulation of mononuclear cells with only minimal fibrotic changes which were resolved after day 28. Lipopeptide conjugates based on the head group tripalmitoyl-S-glyceryl-cysteinyl-serin (P3CS) can thus be used as effective immunogens and adjuvants without long-term tissue damage.

Spinal empyema in Crohn's disease

A 19-year-old man with a 1-year history of Crohn's disease of the ileum and rectosigmoid developed back and leg pain with neurological deficits. He proved to have an epidural and subdural spinal empyema originating from a rectal fistula. Drainage of the empyema, a diverting sigmoid colostomy, and appropriate antibiotics allowed full recovery of neurologic function and resolution of infection. We review the applicable literature.

Dispase, a neutral protease from Bacillus polymyxa, is a powerful fibronectinase and type IV collagenase

Dispase, a neutral protease isolated from culture filtrates of Bacillus polymyxa, has proven to be a rapid, effective, but gentle agent for separating intact epidermis from the dermis and intact epithelial sheets in culture from the substratum. In both cases it effects separation by cleaving the basement membrane zone region while preserving the viability of the epithelial cells. Because it is not known what or where in the basement membrane zone Dispase cleaves, we set up studies to define its substrate specificity. Using purified basement membrane components and sodium dodecyl sulfate-polyacrylamide gel electrophoresis we show that Dispase cleaves fibronectin and type IV collagen, but not laminin, type V collagen, serum albumin, or transferrin. The action of Dispase on collagen appears to be selective for type IV collagen in that several stable degradation products are formed, whereas the enzyme degrades type I collagen only minimally. In newborn human skin, as seen by electron microscopy, Dispase removes the lamina densa, rich in type IV collagen, but preserves the anchoring fibrils (structures known to contain type VII collagen) and the epidermal cells. Because its action is so selective, it suggests that Dispase can serve as a powerful tool for dissecting epithelial-mesenchymal interactions.

Mortality study of persons exposed to dioxin in a trichlorophenol-process accident that occurred in the BASF AG on November 17, 1953

Twenty-seven years after an accident which occurred in the BASF, Ludwigshafen plan in 1953, a mortality study of persons exposed to dioxin in an uncontrolled reaction during a trichlorophenol process was undertaken. The follow-up was 100% successful and involved 74 persons. Overall mortality (21 deaths) did not differ in this group from the rate expected in three external reference populations or from that observed in two internal comparison groups, where 18-20 deaths were observed. Of the 21 deceased persons, 7 had cancer, compared with 4.1 expected. In addition, two other cases of cancer (one bronchial carcinoma, and one carcinoma of the prostate) are still alive. Three deaths due to stomach cancer, at ages 64, 66, and 69 years, were found, compared with 0.6 expected from regional mortality data. One stomach cancer occurred among 148 individuals in the two comparison cohorts.

Histone phosphorylation in phorbol ester stimulated and beta-adrenergically stimulated mouse epidermis in vivo and characterization of an epidermal protein phosphorylation system

Under certain physiological conditions a change in the phosphorylation of histones in mouse epidermis in vivo was observed. Thus a single local application of the tumor-promoting mitogen 12-O-tetradecanoylphorbol-13-acetate caused a long-lasting increase of histone H1 phosphorylation which paralleled stimulated cell proliferation. Injection of the antimitotic beta-adrenergic agonist isoproterenol led to a temporary decrease in the rate of phosphorylation of H1, H2A and H2B immediately after cyclic AMP accumulation. A complete protein phosphorylation system could be demonstrated in mouse epidermis homogenates. The following enzyme activities were partially purified and characterized: a cyclic AMP-dependent histone kinase; a 'casein kinase' and an 'unspecific' protein kinase; a histone-specific protein phosphatase; and two 'unspecific' phosphoprotein phosphatases. In addition, a stimulatory effect of cyclic GMP on histone phosphorylation was observed. The enzymes were found to be predominantly localized in the 105000 X g supernatant, but a small proportion of protein kinase and phosphatase activity could be regularly demonstrated in cell nuclei.