Isolation of bacteriophages specific for the K1 polysaccharide antigen of Escherichia coli.

Five bacteriophage stocks were prepared after enrichment of a sewage sample using Escherichia coli 02:K1:H4 (strain U9/41). The bacteriophages were tested for their ability to lyse 224 strains of E. coli that had been tested for the presence of the K1 antigen by means of an antiserum-agar diffusion technique, using a meningococcus group B antiserum known to detect the E. coli K1 antigen. The standard test strains for E. coli K antigens 2 to 99 were used as control strains. Of the 101 strains found to possess the K1 antigen using the antiserum-agar technique, 93 were lysed by at least one of the bacteriophages, whereas 8 of the 123 strains apparently lacking K1 were lysed by one or more of the bacteriophages. None of the standard test strains for K antigens 2 to 99 was lysed by any of the bacteriophages. The eight strains thought to lack K1 but that were lysed by bacteriophage were re-examined by immunoelectrophoresis, using meningococcus group B antiserum; five of the eight strains gave a precipitin line corresponding to K1. The use of K1-specific bacteriophages offers an inexpensive and easy method for the identification of the K1 antigen.     

Dupilumab is effective in type 2-high asthma patients receiving high-dose inhaled corticosteroids at baseline

Background

Dupilumab blocks the shared receptor component for interleukin (IL)-4/IL-13, key drivers of type 2 inflammation. In phase 2b (NCT01854047) and phase 3 LIBERTY ASTHMA QUEST (NCT02414854), add-on dupilumab 200/300 mg every 2 weeks (q2w) reduced severe exacerbations, improved prebronchodilator (pre-BD) forced expiratory volume in 1 second (FEV₁) and quality of life measures, and it was generally well tolerated in patients with uncontrolled, persistent (phase 2b), or moderate-to-severe (phase 3) asthma.

Methods

In patients on high-dose inhaled corticosteroids (ICS) with type 2-high asthma (subgroups including baseline blood eosinophils ≥150/300 cells/µL and/or fractional exhaled nitric oxide [FeNO] ≥25 ppb), annualized severe exacerbation rates over the treatment period, changes from baseline in pre-BD FEV₁ and asthma control (5-item asthma control questionnaire [ACQ-5]) were analyzed.

Results

In high-dose ICS type 2-high subgroups, dupilumab 200/300 mg q2w vs placebo in the phase 2b (24 weeks) and phase 3 (52 weeks) studies significantly reduced severe exacerbations by 55%-69%/57%-60% (all P<.05) and 53%-69%/48%-66% (all P < .001), respectively, except in patients with ≥ 300 eosinophils/µL in phase 2b study (24%/50% (P = .52/0.15). Across subgroups, pre-BD FEV₁ improved by 0.18-0.22 L/0.19-0.24 L (all P < .05) and 0.23-0.36 L/0.15-0.25 L (all P < .01) and ACQ-5 scores were reduced by 0.46-0.55/0.47-0.85 (all P < .05) and 0.38-0.50/0.24-0.30 (all P < .05), respectively, except dupilumab 200 mg q2w in phase 2b in patients with FeNO ≥ 25 ppb (0.41; P = .09). Dupilumab was also effective in patients taking medium-dose ICS.

Conclusion

Dupilumab significantly reduced severe exacerbations and improved lung function and asthma control in patients with type 2-high asthma on high-dose ICS at baseline.

     

Expression of epithelial and neural antigens in small cell and non small cell lung carcinoma

Seventy-one lung carcinomas from 66 different patients were stained with a panel of monoclonal antibodies. Twenty-nine were small cell lung carcinoma (SCLC), 15 adenocarcinomas, 17 squamous carcinomas and 10 large cell carcinomas. Three of the monoclonal antibodies recognize different cytokeratins, three recognize other epithelial antigens and one recognizes a neural antigen. Both formalin-fixed and cryopreserved tumours were studied using an indirect immunoperoxidase method. 23/29 SCLC reacted with all but one of the antibodies which recognize epithelial antigens. This staining was similar to that seen in non small cell lung carcinomas (NSCLC) and provides further evidence that SCLC are true epithelial tumours. All but one of the SCLC stained with the antibody recognizing a neural antigen. This antibody did not stain squamous or adenocarcinomas. However, four of the large cell carcinomas stained well with this antibody, suggesting that SCLC and some large cell carcinomas share a common pathway of differentiation. There were variations of staining seen both within and between tumours. This has obvious implications if immunotargetting with monoclonal antibodies is to be used diagnostically or therapeutically.     

Effects of the oral converting enzyme inhibitor SQ 14225 in experimental high output failure.

The relation of the renin-angiotensin-aldosterone system to sodium retention was studied in dogs with an aortic-caval fistula and high output failure by administering orally the new converting enzyme inhibitor SQ 14225. The acute response to an initial oral dose of SQ 14225 (10 mg/kg) consisted in a fall in arterial pressure (BP) from 97 to 67 mmHg, plasma aldosterone concentration (PAC) from 21.7 to 11.3 ng/100 ml, creatinine clearance (CCr) from 89 to 44 ml/min, and filtration fraction (FF) from 39 to 18%, whereas plasma renin activity (PRA) increases from 12.7 to 36.1 ng angiotensin I.ml-1.h-1 and renal sodium excretion was unchanged. It is suggested that the marked fall in BP and CCr offset the drop in PAC and FF which favored a natriuresis. The daily responses to SQ 14225 for 3 days also showed a fall in BP and PAC but sodium excretion increased. In the animal with the best response, a striking natriuresis occurred. These findings demonstrate an important role for the renin-angiotensin-aldosterone system in experimental high output failure.     

Distinctions between endemic and sporadic forms of Epstein-Barr virus-positive Burkitt's lymphoma

Tumour cell lines were established in vitro from 16 cases of Epstein-Barr (EB) virus genome-positive Burkitt's lymphoma (BL), 7 of "endemic" origin (i.e. from holoendemic malarial areas of Africa and of New Guinea) and 9 of "sporadic" origin (i.e. from outside such high-incidence areas). All the BL cell lines thus established were monoclonal by immunoglobulin isotype expression and displayed a characteristic chromosomal translocation, t(8:14) or t(8:22), confirming their malignant origin. Clear differences observed between the individual BL cell lines appeared to be related to their endemic or sporadic status. All 7 endemic cell lines began growth as a carpet of single cells, often with small, loose clumps appearing in later passage. Whilst 3 lines of sporadic origin displayed a similar pattern to the above, the majority of sporadic lines grew as large, tight clumps of cells from the first passage onwards. These differences in growth pattern were reflected by differences in cell surface phenotype, as defined in indirect immunofluorescence tests using a panel of monoclonal antibodies (MAbs) specific for B-lineage-associated antigens. BL cell lines could be classified into 3 separate groups on the basis of their reactivity with 6 particular antibodies (MHM6, AC2, Ki-1, Ki-24, J5 and 38.13). All 7 endemic BL cell lines and 2 of the 3 sporadic BL cell lines which began growth as single cells showed a group-I cell-surface phenotype (MHM6, AC2, Ki-1, Ki-24 negative; J5, 38.13 positive) in early passage. In contrast, all 6 sporadic BL cell lines which began growth in large clumps displayed a distinct group-II phenotype (MHM6, AC2, Ki-1 positive/negative; Ki-24, J5, 38.13 positive); in later passage most of these sporadic lines progressed to a group-III phenotype (MHM6, AC2, Ki-1, Ki-24 positive; J5, 38.13 negative) without loss of those immunoglobulin and chromosomal markers identifying the cells' malignant origin. These clear differences between endemic BL cell lines on the one hand and the majority of sporadic BL cell lines on the other suggest that endemic BL arises from a more restricted range of progenitor B cells than does the sporadic form of the disease.     

A FOCUS on computerization.

Regardless of the amount of information available today relative to radiology management information systems, the manager with minimum experience needs to "focus" attention on specific aspects of computerization during the selection and implementation processes. This article defines those areas of interest that can contribute to the overall success and acceptance of a system.     

218. Prostaglandin E I verhindert die Aspirin-bedingte Ischämie der Magenmucosa; ein Mechanismus der Cytoprotektion?

Zusammenfassung Der Mechanismus der Cytoprotektion von Prostaglandin (PG) auf die Magenmucosa ist unbekannt. Anaesthesierte Kaninchen erhielten in der Gruppe (GR) I (n=8) im. Aspirin (ASA) (100 mg/kg als Bolus, 66 mg/kg/h kontinuierlich) in der GR 11 (n=10) NaCI und in der GR III (n=7) zusätzlich zum ASA, PGE I (0,1 g/kg/min) als Infusion über 120 min. Der Mucosa-Blutfluß (MBF) wurde mit radioaktiven Mikrosphären gemessen. In der GR I fiel der MBF nach 15 min um 72,3+3,8% (+ SEM) und nach 120 min um 73,1+3,8% (p 0,05 gegen % Änderung in GR II und III). Nach 120 min zeigte sich in der GR I 19,8 + 7,6% der Fundusmucosa hämorrhagisch, in der GR 11 6,1 +5,2% und in der GR 1112,0+ 1,4% (p 0,05 gegen GR II und III). Wir schließen, daß der cytoprotektive Effekt des PGE I auf einer Aufhebung der ASA bedingten Mucosaischämie beruht.     

Tezacaftor/ivacaftor in people with cystic fibrosis who stopped lumacaftor/ivacaftor due to respiratory adverse events

BackgroundIncreased rates of respiratory adverse events have been observed in people ≥12 years of age with cystic fibrosis homozygous for the Phe508del-CFTR mutation treated with lumacaftor/ivacaftor, particularly in those with percent predicted forced expiratory volume in 1 s (ppFEV₁) of <40%. We evaluated the safety, tolerability, and efficacy of tezacaftor/ivacaftor in people with cystic fibrosis homozygous for Phe508del-CFTR who discontinued lumacaftor/ivacaftor due to treatment-related respiratory signs or symptoms.MethodsParticipants ≥12 years of age with cystic fibrosis homozygous for Phe508del-CFTR with ppFEV₁ of ≥25% and ≤90% were randomized 1:1 and treated with tezacaftor/ivacaftor or placebo for 56 days.ResultsOf 97 participants, 94 (96.9%) completed the study. The primary endpoint was incidence of predefined respiratory adverse events of special interest (chest discomfort, dyspnea, respiration abnormal, asthma, bronchial hyperreactivity, bronchospasm, and wheezing): tezacaftor/ivacaftor, 14.0%; placebo, 21.3%. The adverse events were mild or moderate in severity. None were serious or led to treatment interruption or discontinuation. Overall, the discontinuation rate was similar between groups. The mean (SD) ppFEV₁ at baseline was 44.6% (16.1%) with tezacaftor/ivacaftor and 48.0% (18.1%) with placebo. The posterior mean difference in absolute change in ppFEV₁ from baseline to the average value of days 28 and 56 was 2.7 percentage points with tezacaftor/ivacaftor vs placebo.ConclusionsTezacaftor/ivacaftor was generally safe, well tolerated, and efficacious in people ≥12 years of age with cystic fibrosis homozygous for Phe508del-CFTR with ppFEV₁ of ≥25% and ≤90% who previously discontinued lumacaftor/ivacaftor due to treatment-related respiratory signs or symptoms.