Exploring suicidal behaviours by probation clients-a qualitative near-lethal study

Background

Existing research emphasizes that offenders serving community based sentences are at an increased risk of suicide compared with the general population, however, there is little understanding about the causes of this risk. The aim of the current research was to understand how to support probation clients and prevent suicide, by exploring the experiences of probation clients who carried out near-lethal suicide attempts whilst under probation supervision.

Methods

In-depth interviews were carried out with seven probation clients who made near-lethal suicide attempts whilst serving a probation sentence. Data were analysed using Interpretative Phenomenological Analysis.

Results

Participants recounted negative experiences which they perceived to be linked to their suicidal feelings and behaviours, such as experiencing bereavements, perceived loss of control over their mental state or situation, and difficulties relating to stages of their probation sentence. Participants expressed severe difficulties with trusting authorities, making disclosure of suicidal feelings problematic. However, participants emphasized the role that purposeful and meaningful activity can play in suicide prevention.

Conclusions

Suicide prevention strategies must be tailored to the needs of probation clients across the UK. Mandatory training for probation staff is recommended to help reduce suicides, and support from external agencies should be sought where possible.

HIV-1 Aspartic Proteinase: High-Level Production and Automated Fluorometric Screening Assay of Inhibitors

The 99-amino-acid HIV-1 aspartic proteinase was expressed to high levels in Escherichia coli using a T7 expression system. About 50% of the insoluble material after sonication of the bacteria was composed of aggregated proteinase. Subsequent renaturation and purification yielded large quantities of a homogeneous enzyme able to cleave various heptapeptidic substrates in vitro with a Km around 2.5 mM. A fluorometric assay has been devised to allow automated screening of HIV proteinase inhibitors based on an analogous renin assay. We used the synthetic intramolecularly quenched fluorogenic substrate Suc-TLNFPIS-4MCA based on the heptapeptide TLNFPIS, which encompasses the proteinase/reverse transcriptase junction, coupled to the fluorophore 7-amino-4-methylcoumarin and blocked at the amino-terminus by a succinyl group. The enzyme cleaves the substrate between phenylalanine and proline, and conditions were optimized for liberation of 7AMC from the generated PIS-4MCA with aminopeptidase M as secondary enzyme. 7AMC was monitored with a microplate fluorescence scanner. The known aspartic proteinase inhibitor pepstatin A consistently gave Ki = 2 × 10−6M. Other synthetic and natural compounds are currently being tested.

Journeys of adjustment: the experiences of adolescents living with juvenile idiopathic arthritis

BACKGROUND

Juvenile idiopathic arthritis (JIA) is one of the most common diseases of childhood causing pain, swelling of joints and reduced mobility. Previous research has focused on the challenges and psychosocial impact of JIA, but there has been limited attention given to how young people adjust and adapt to living with a long-term condition such as JIA. The aim of this qualitative study was therefore to explore adolescents' experiences of living with JIA, with particular focus on the process of adjustment.

METHODS

Ten adolescents (7 female, 3 male) aged 13-17 years with good treatment adherence were recruited from an adolescent arthritis clinic. In-depth interviews were conducted, and data were analysed by two researchers independently using interpretative phenomenological analysis.

RESULTS

These adolescents described the physical and psychosocial 'burden of living with JIA' and the challenges faced by an underlying preoccupation 'to be a normal teenager'. However, their accounts also revealed ways in which they regained agency and developed 'resilience through taking control' over their lives. This resilience helped the adolescents re-establish a sense of well-being through an ongoing process of 'acceptance and self-growth'.

CONCLUSIONS

Although much research has adopted a deficit model that focuses on adjustment problems, the current study highlights the resourcefulness of young people in managing the challenges of living with a long-term condition. These experiences of successful adjustment can be used as the basis of positive, strength-based intervention approaches for adolescents with arthritis to enhance resilience and well-being.

Effect of the 12-gene colon cancer assay results on adjuvant treatment recommendations in patients with stage II colon cancer

INTRODUCTION

The 12-gene colon cancer Recurrence Score assay is a clinically validated predictor of recurrence risk in stage II colon cancer patients. A survey was performed characterizing the assay's impact on treatment recommendations for these patients.

METHODS

US medical oncologists (n = 346) who ordered the assay for ≥3 stage II colon cancer patients were asked to complete a web-based survey regarding their most recent such patient. Physicians surveyed represented users of the assay within the first 2 years of commercial availability which may include 'early adopters'.

RESULTS

Most of 116 eligible physicians were in community practice (86%), with median 14.5 years' experience (range = 2-40). Mean patient age was 61 years (range = 32-85); 81% had T3 disease, and 38% had comorbidities. Of 76 patients tested for mismatch-repair/microsatellite-instability (MMR/MSI), 13 (17%) were MMR-deficient/MSI-high; 46 (61%) MMR-proficient/MSI-low; and 17 (22%) unknown. Most patients (84%) had ≥12 nodes examined. Median Recurrence Score result was 20 (range = 1-77). Before assay, treatment recommendations were specified for 92 (79%) patients, with no recommendation for 24 (21%). Of the 92 with pre-assay recommendations, chemotherapy was planned for 52 (57%) and observation for 40 (43%); the assay changed recommendations for 27 (29%). Treatment intensity decreased for 18 (67%) and increased for nine (33%) patients; it was more likely to decrease for lower Recurrence Score values and increase for higher values (p < 0.001).

CONCLUSION

For stage II colon cancer patients receiving Recurrence Score testing, 29% of treatment recommendations were changed. Use of the assay may lead to reductions in treatment intensity. Study limitations include retrospective design, data gathering during the first 2 years of assay availability only, and potential non-representativeness of respondents.

Abstract P2-11-16: Cardiac Morbidity After Adjuvant Chemotherapy (CT) for Early Breast Cancer in the Community Setting

Cardiac morbidity after exposure to CT is a known and previously described risk. Anthracycline exposure can be complicated by acute or chronic cardiac toxicity. Trastuzumab exposure is largely associated with acute and reversible cardiac morbidity.

Methods: We retrospectively queried the electronic health record (EHR) from our network of community oncology practices, iKnowMed, for patients (pts) diagnosed with Stage I-III breast cancer (BC) from 2007–2010 with at least 5 visits and follow-up (f/u) through 2012. We stratified this group by CT utilization (yes/no), regimen type, age, and characterized the incidence of cardiac disease or initiation of cardiac medication through the f/u period to determine the association of cardiac disease or treatment with CT utilization. Cardiac diseases analyzed included congestive heart failure, valvular and ischemic heart disease, arrythmias, and hypertension. Cardiac medications included beta blockers, angiotensin-converting-enzyme inhibitors, angiotensin receptor II blockers, loop and thiazide diuretics. Hazard ratios by prespecified risk parameters were then analyzed by multivariate analysis for all pts who did not have cardiac disease preceding their diagnosis of BC.

Results: We identified 20,900 pts with a median f/u of 3.2 yrs (1.4–5.4). 11,295 (54%) pts received adjuvant CT and 9,605 (46%) did not. Median age at diagnosis in the CT-treated arm and non CT-treated arm was 54 and 64 yrs, respectively (p &lt; 0.0001). Among both the non-CT and CT-treated group, the baseline prevalence of cardiac disease was 14%. Among the CT-treated group, 3475 pts or 31% (95% CI, 30 %−32%) had or developed cardiac disease within the study period. In the non-CT group, 3790 pts or 39% (95% CI, 38%−40%) had or developed cardiac disease with the study period (p &lt; 0.01). Receiving CT conveyed a lower risk of cardiac morbidity overall, HR 0.86 (p &lt; 0.01). Incidence of cardiac disease was higher among pts who were in the non-CT treated arm (39%) than among the various CT-treated arms: anthracycline and trastuzumab (30%), anthracycline without trastuzumab (26%), non-anthracycline with trastuzumab (33%), and non-anthracycline without trastuzumab (34%). Incidence of cardiac disease increased proportionally over time in all age groups as expected in both cohorts.

Illness perceptions, coping and quality of life in patients with alopecia

BACKGROUND

Alopecia can have substantial psychological consequences, but there has been no research looking at patients' beliefs about their condition nor how they relate to quality of life (QoL).

OBJECTIVES

To investigate the relationships between illness perceptions, coping and QoL in patients with alopecia.

METHODS

The study employed a cross-sectional design. In total, 214 individuals with alopecia were recruited from four internet support groups. There were 171 women and 43 men (mean age 35 years). Participants completed an online questionnaire comprising the Revised Illness Perception Questionnaire, the Dermatology Life Quality Index and the brief COPE.

RESULTS

The findings indicate several areas in which alopecia impacted on individuals' QoL, particularly in relation to symptoms and feelings. Women reported poorer QoL compared with men. Impaired QoL was associated with a strong illness identity, beliefs in the serious consequences of alopecia and strong emotional representations. Hierarchical multiple regressions indicated that illness perceptions accounted for 35% of the variance in QoL after controlling for demographic and disease factors, with coping adding a further 7% to the regression model.

CONCLUSIONS

Although alopecia is not a life-threatening condition, it can impair QoL by negatively impacting on self-awareness. The strong relationships found between patients' beliefs about their condition and QoL suggests that health professionals should recognize the psychological impact of alopecia and address negative beliefs and emotions surrounding the condition in treatment programmes.

Interaction of human angiogenin with copper modulates angiogenin binding to endothelial cells

Angiogenin is a potent inducer of blood-vessel formation with ribonucleolytic activity. Angiogenin binds to high affinity endothelial cell receptors and with lower affinity to extracellular matrix components. Here we report the effect of copper and zinc on these interactions. There was a 4.3-fold increase in angiogenin binding to calf pulmonary artery endothelial cells in the presence of Cu2+ in vitro. A 3.8-fold increase was observed with Zn2+, whereas Ni2+, Co2+, or Li+ had no effect. Specific angiogenin binding to the lower affinity matrix sites was increased by 2.7- and 1.9-fold in the presence of Cu2+ and Zn2+ respectively. Metal ion affinity chromatography and atomic absorption spectrometry were used to show the direct interaction of angiogenin with copper and zinc ions. Angiogenin bound 2.4 mol of copper per mole of protein. We suggest that copper, a modulator of angiogenesis in vivo, may be involved in the regulation of the biological activity of angiogenin.

Natural and structured baselines in the treatment of aggression following brain injury

This single-case study describes the importance of presenting relevant baseline conditions in planning and evaluating treatment for aggression in a severely brain injured man 1 year after injury. An artificially low natural baseline resulted from staff reluctance to deliver instructions and corrective feedback needed for rehabilitation of self-care skill because these were frequently followed by aggression. A subsequent structured baseline presented these antecedents at the higher rates that were necessary for progress in the patient's rehabilitation. This resulted in an increase in aggressive behaviour, but also gave a more accurate representation of what his behaviour would be like under effective rehabilitation conditions. Intervention was based on data from the structured baseline, and included providing clear expectations, social reinforcement, and decelerative procedures. After reduction of aggression to zero, regular staff were reintroduced and presented instruction and corrective feedback as required. No further aggressive behaviour was noted, and self-care improved so that only minimal assistance was needed. Six months following reintroduction of regular staff, both baseline conditions were replicated. No aggressive behaviour was observed during either, suggesting that maintenance of gains could not be attributed to an artificially reduced rate caused by staff avoiding trigger antecedents.

Traumatic rupture of an aortic ulcerative atherosclerotic plaque producing aortic dissection: a complication of interscapular back blows used to dislodge objects from the esophagus

Penetrating atherosclerotic ulcer of the aorta is a rare entity which usually occurs in the descending thoracic aorta. Herein, we report an unusual case of penetrating aortic ulcer which ruptured into the mediastinum. Interscapular back blows were performed on our patient in an attempt to dislodge an aspirin which she thought was lodged in her esophagus. Unlike previously reported cases of this entity, the penetrating aortic ulcer in our patient was located in the distal thoracic ascending aorta. Diagnosis of penetrating aortic ulcer can be made by utilizing aortography, contiguous dynamic contrast-enhanced computed tomography or magnetic resonance imaging. Treatment consists of adjunctive medical therapy until surgery can be performed.

Process economics of animal cell and bacterial fermentations: a case study analysis of tissue plasminogen activator

One link in the complex chain of medical economics is the cost of bringing new drugs and biologicals to the market. Advances in recombinant-DNA technology permit production of therapeutically active proteins in effectively unlimited quantities. Nevertheless, each expression system has a characteristic influence on the nature of the product produced and the process required to obtain it. In this case study we compare experiences with recombinant-tissue plasminogen activator (rtPA) produced in Chinese hamster ovary (CHO) cells and in Escherichia coli, with the aim of understanding the roles of some of the parameters that affect process economics. tPA belongs to the group of highly specific serine proteases that convert plasminogen to plasmin, which in turn degrades several protein substrates including fibrin, thus making it an effective thrombolytic agent. The treatment of acute myocardial infarction with such thrombolytic agents can result in early discharge of patients and decreased medical costs. However, there are major differences in the prices of the various available agents. The price of the FDA-licensed tPA product is $2,200 per dose or $22,000 per gram. It is believed that a significant portion of this price relates to manufacturing costs. We examine by way of case study illustration the cost breakdown for the two processes, and highlight important process, design and economic considerations that ultimately define a particular protein product.

Moral Philosophy and Nursing Curricula: Indoctrination of the New Breed

A sizable proportion of nursing curricula subtly indoctrinate students with a particular normative ethic. Seldom is there adequate philosophical justification for the ethic, and students are rarely invited to subject that ethic to a rigorous philosophical analysis. Nursing curricula are replete with philosophical positions treated as moral imperatives to which all, students and faculty, owe their allegiance. This unsatisfactory situation warrants urgent attention. One problem is that of failing to justify the school's moral philosophy; another is the question of philosophically indoctrinating students to adhere to an ethic that advocates the individual's freedom and responsibility, a practice inconsistent with the predominant proposition advanced by the ethic.

Identification of the main epitope on human cytochrome P450 IID6 recognized by anti-liver kidney microsome antibody

Antibodies present in the sera of a group of children with autoimmune hepatitis react with human cytochrome P450 IID6. cDNA constructions of various fragments of human P450 IID6 were made and expressed and the resulting peptides were tested in immunoblot with patients' sera. These allowed identification of at least two antigenic sites on the P450 molecule. The main one, recognized by all sera tested, is located between amino acids 239 and 271. Synthesis of three peptides covering this area of the molecule allowed identification of a sequence of three amino acids (tyrosine-tryptophane-asparagine) located at position 261-263 that constitutes the essential part of the epitope. A protein sequence data-base search revealed homologies between this region of human P450 and proteins from Salmonella typhimurium, from human T lymphotropic virus types 1 and 2 and Herpes simplex virus type 1.

Low molecular weight, sequence based, collagenase inhibitors selectively block the interaction between collagenase and TIMP (tissue inhibitor of metalloproteinases)

Sequence-based inhibitors of collagenase bearing an hydroxamate group capable of chelating the active site zinc atom were synthesized and tested. The effect of one of these molecules (RP 59794; Ki about 10(-8) M) on the formation of the TIMP: collagenase complex was also tested. RP 59794 blocks complex formation and can partially dissociate established TIMP: collagenase complexes. It exhibits the same stereospecificity in this activity as in its inhibition of collagenase suggesting that TIMP and RP 59794 both interact with the active site region of collagenase.

Oncogenic proteins new targets for chemotherapeutic agents against cancer

Over the past 10 years, more than 40 potentially oncogenic genes, termed protooncogenes, have been identified in the human genome. Little is known of the physiological role of the proteins encoded by these genes, but they seem to be involved in the reception and transmission of hormonal and other environmental information from the cell membrane to the nucleus. These proteins may acquire transforming properties when over-expressed or if structurally altered following partial deletions or point mutations. Cytogenetic analysis shows loss of genetic material from specific chromosomal loci in many human tumors, suggesting that the absence of a functional gene at these loci may permit tumor development. The genes involved have been termed "anti-oncogenes". Understanding the control mechanisms of cell proliferation is essential in order to understand how cancer cells escape from this control. To this end, numerous oncogenes have been cloned, permitting the production of modified forms of oncogenic proteins and identification of the regions essential for their biological activity. Availability of large amounts of protein also allows the production of specific antibody which can be used to verify whether blockage of a given protein results in reversion of the transformed phenotype. If it can be shown that the expression of an oncogenic protein is essential for transformation, it should be possible to search for molecules that inhibit its action or which mimic the effects of an anti-oncogene. This type of research is already well advanced for the oncogenic ras proteins, and models have been established that permit both screening for potential inhibitors and design of specific antagonists.

Specific binding of angiogenin to calf pulmonary artery endothelial cells

Specific binding of angiogenin (ANG) to calf pulmonary artery endothelial cells was demonstrated. Cellular binding at 4 degrees C of 125I-labeled human recombinant ANG was time and concentration dependent, reversible, and saturable in the presence of increasing amounts of the unlabeled molecules. The interaction was shown to be specific since a large excess of unlabeled ANG reduced labeled ANG binding by 80%, whereas similar doses of RNase A, a structurally related protein, had no effect. Scatchard analyses of binding data revealed two apparent components. High-affinity sites with an apparent dissociation constant of 5 x 10(-9) M were shown to represent cell-specific interactions. The second component, comprising low-affinity/high-capacity sites with an apparent dissociation constant of 0.2 x 10(-6) M, was essentially associated with pericellular components. High-affinity ANG binding sites varied with cell density and were found on other endothelial cells from bovine aorta, cornea, and adrenal cortex capillary but not on Chinese hamster lung fibroblasts. Divalent copper, a modulator of angiogenesis, was found to induce a severalfold increase in specific cell-bound radioactivity. Placental ribonuclease inhibitor, a tight-binding inhibitor of both ribonucleolytic and angiogenic activities of ANG, abolished 125I-labeled human recombinant ANG binding only in the absence of copper.

[Natural inhibitor of metalloproteinases: structural and functional study]

A potent collagenase inhibitor was purified from cells of calf aorta medial tissue maintained in culture. This molecule was characterized and identified as TIMP (Tissue Inhibitor of Metalloproteinases). Formation of a TIMP--collagenase complex was demonstrated chromatographically using pure TIMP and pure pig synovial cell collagenase. The N-terminal aminoacid sequence of TIMP was determined and, using appropriate oligonucleotide probes the human genes was cloned from a human cDNA bank. This gene was expressed in E. coli, and fully active TIMP was obtained after a denaturation renaturation process. The interest of TIMP as a model for the design of novel collagenase inhibitors is discussed.

[Inhibition of synovial collagenase by actinonin. Study of structure/activity relationship]

Actinonin is a pseudopeptide antibiotic which inhibits collagenase at micromolar concentrations [10]. In this study, Actinonin analogs were tested to investigate "structure/activity" relationships for this class of molecule. The results indicate that distance between the hydroxamate carbonyl group and that of the first amide bond is important, since increasing this distance by a methylene group, decreases inhibition by a factor of 100. The amide bonds of this inhibitor must be in the peptide bond orientation. Different N terminal amide derivatives and different hydrophobic substituents adjacent to the hydroxamate residue, had little effect on inhibitory activity. However, in this series of molecules, two hydrophobic groups separated by an amide bond seem to be necessary for potent inhibition.

Arrhythmia and late mortality after Mustard and Senning operation for transposition of the great arteries. An eight-year prospective study

Arrhythmia and late sudden death are recognized complications of intraatrial repair of transposition of the great arteries. We performed a prospective study over 8 years in 100 consecutive hospital survivors who underwent Mustard (46 patients) or Senning (54 patients) operations between 1978 and 1982. Arrhythmia was analyzed by preoperative, postoperative, and serial follow-up Holter monitoring and standard electrocardiograms and was related to clinical outcome. Before repair, all patients were in sinus rhythm with a low incidence of arrhythmia. After repair, there was a gradual decrease in stable sinus rhythm during follow-up so that at a mean of 7 years after operation only 56% of patients having the Senning operation and 66% having the Mustard, with simple transposition, were in stable sinus rhythm on Holter monitoring. There was no significant difference between the two operations. Eleven patients (five after Senning [two simple, three complex], six after Mustard [five simple, one complex]) died during follow-up, four suddenly (two after Senning, two after Mustard). However, loss of sinus rhythm or the presence of arrhythmia on standard electrocardiograms or Holter recordings did not identify patients at risk for increased morbidity or mortality. Thus, even with current surgical techniques, gradual loss of sinus rhythm occurred after both Mustard and Senning operations. Because late death could not be predicted by electrocardiographic analysis, an alternative approach involving detailed hemodynamic and electrophysiologic measurements may be required to identify high-risk patients.

Monoclonal antibodies against synovial collagenase: use for immunopurification and characterization of the latent and active enzyme

Monoclonal antibodies have been produced against porcine synovial collagenase which recognize both the active enzyme and its inactive precursor. These antibodies inhibited the collagenolytic activity of collagenase, but not its activity with a synthetic peptide substrate. The antibodies were also able to recognize human synovial, human skin fibroblast and human chondrocyte collagenase but not the enzyme from human granulocytes. One of the monoclonal antibodies was successfully used for the immunopurification of the porcine enzyme and these experiments led to the demonstration of an endogenous activator of procollagenase in the synovial cell culture medium.

An inhibitor of mammalian collagenase active at micromolar concentrations from an actinomycete culture broth

Anti-collagenase activity was detected in the culture supernatant of an Actinomycete strain S 4373. The molecule was purified by solvent extraction, medium pressure and high pressure reverse phase chromatography and finally by HPLC gel filtration. The pure product was analyzed by mass spectroscopy and was identified as actinonin, a known pseudopeptide antibiotic. The Ki was determined as 1.4 microM and this value was confirmed using pure synthetic actinonin.

Effect of peptide chain length on absorption of egg protein hydrolysates in the normal human jejunum

The influence of the peptide chain length of partial enzymic hydrolysates of protein on nitrogen and amino acid absorption was studied in 12 subjects using a jejunal perfusion technique. Three hydrolysates of egg white and an equivalent amino acid mixture were perfused at 30 mmol/L and 100 mmol/L in two separate experiments. Two hydrolysates (OH1 and OH2) contained mainly dipeptides and tripeptides, whereas the third (OH3) comprised tripeptide to pentapeptides as judged chromatographically. Nitrogen absorption was significantly slower from the higher chain length mixture, OH3, than from the short chain mixtures, OH1 and OH2, at both concentrations. Similarly, several amino acid residues were absorbed less well from OH3 than from OH1 and OH2. These data demonstrate that the chain length of heterogeneous mixtures of peptides affects absorption of nitrogen and individual amino acid residues, and suggest that brush border hydrolysis of tetrapeptides and pentapeptides limits absorption from enzymic hydrolysates of protein which simulate the composition of the postprandial luminal contents.

Chemical synthesis of a gene coding for human angiogenin, its expression in Escherichia coli and conversion of the product into its active form

A synthetic gene coding for human angiogenin was synthesized by solid support phosphoramidite chemistry as eight long oligodeoxynucleotides which were subsequently assembled and cloned in Escherichia coli. The gene was designed to use codons found in highly expressed E. coli proteins. A pBR322-derived expression vector was constructed containing the E. coli trp promoter, the ribosome-binding site of the bacteriophage lambda cII gene, the angiogenin coding sequence, and the transcription terminator region of the E. coli rrnB operon. Under tryptophan deprivation, angiogenin was strongly expressed in E. coli cells at a yield of 5-10% of total protein. The eukaryotic protein was found to be insoluble but could be easily renatured and purified. The purified angiogenin was demonstrated to be active as an angiogenic factor and exhibited a characteristic RNase activity.

Localization of a neutralization epitope of foot-and-mouth disease virus using neutralizing monoclonal antibodies

Neutralizing monoclonal antibodies raised against intact foot-and-mouth disease virus reacted with intact particles and with isolated VP1 from different strains from the same subtype. Prior treatment of the virus with either trypsin or with arginine-specific protease abolished recognition of both the virus and of VP1, suggesting the presence of a neutralization epitope in the central region of VP1 cleaved by these two enzymes. A synthetic peptide analogue of part of this region showed poor reactivity, however, with neutralizing antibody.

Partial separation of blood clotting factors, albumin, and IgG by continuous free film electrophoresis

Blood plasma and factor VIII concentrate have been fractionated by continuous free film electrophoresis in an apparatus which was designed to overcome the problems of overheating usually inherent in this technique. Results show that complete separation of plasma proteins is unlikely to be obtained by a single passage through this apparatus. However, a useful degree of fractionation may be obtained with certain proteins, for example fibrinogen and IgG. It should be possible to concentrate blood clotting factors if the electrophoresis is used in combination with a conventional separation procedure such as adsorption on aluminium hydroxide. The advantage of the electrophoretic technique is that it is a continuous process using the minimum of extraneous chemicals. The disadvantage is that it introduces a 40-fold dilution into the fractionation.

Failure of human fibroblast interferon to protect against rhinovirus infection

Volunteers were treated with fibroblast interferon or placebo nose drops for four days. On the second day, they received a challenge with rhinovirus type 4. There was no difference in the clinical symptoms or viral shedding between the two groups. The possible reasons for this result are discussed.

The amino-terminal sequence of human fibroblast interferon as deduced from reverse transcripts obtained using synthetic oligonucleotide primers

From recently published data on the amino-terminal structures of human and mouse interferons, we have predicted and synthesised an oligonucleotide capable of priming specifically the reverse transcription of human fibroblast interferon mRNA present within a total mRNA population. From these transcripts we determined the sequence of the 5'-terminus of the mRNA and identified a putative pre-peptide signal sequence. This enabled us to predict the sequence of another primer capable of directing the synthesis of interferon double-stranded cDNA corresponding to the entire coding region of the mRNA. Further sequencing studies also enabled us to establish the identity of 47 consecutive amino acids beginning with the methionine residue at the amino-terminus of the mature protein.

Skin reactions to interferon inoculations are reduced but not abolished by purification

The skin reactions to partially-purified fibroblast-derived (HulFN-beta) and leucocyte-derived (HulFN-alpha) interferons and to HulFN-alpha of increasing purity were studied in normal volunteers. Reactions consisted of an immediate flare followed by a dense well-circumscribed erythema maximal at 4-8 hours. HulFN-beta caused significantly larger reactions than HulFN-alpha of approximately the same purity. Immediate flare reactions occurred even to the most pure preparation tested but the late reactions were significantly reduced. Experiments suggested that the early reactions to impure HulFN-alpha were in part mediated by local histamine release and late reactions in part by local prostaglandin synthesis. This suggests that interferon itself may not be the cause of general symptoms during a virus illness.

Resolution of human fibroblast interferon into two distinct classes by thiol exchange chromatography

Chromatography of crude and purified human fibroblast interferon on activated thiol Sepharose 4B yielded two classes of material exhibiting different stability to inactivation by mechanical stress. Interferon which bound to the gel accounted for 20--30 per cent of recoverable activity, could be eluted with reducing agents and was unstable. Unbound material did not bind on subsequent rechromatography and was stable to shear forces. Leucocyte interferon did not bind, nor did fibroblast interferon treated with thiol blocking reagents. Peak eluted fractions had a specific activity of up to 10(7.9) units per milligram of protein, representing a 1700 fold purification.

Free Zone Electrophoresis of Clotting Factors

A free-zone electrophoresis system is used for rapid production of substantially purified factor VIII from either citrated plasma or from a factor VIII Concentrate of intermediate purety. Using concentrate, a total yield of 43% of clotting activity is obtained with fibrinogen reduced to approximately 30% of its starting level. Protein level is reduced to 20% of the original value. Using plasma, the albumin, factor VIII and fibrinogen were all separated from factor VIII. In these experiments, factor-VIII-related antigen migrates with the coagulant factor VIII illustrating that both have similar mobilities equivalent to that of an alpha-globulin, or else that they are connected together. The particular advantage of this separation is that it is carried out in a continuous flow apparatus in liquid buffer with no solid matrix and that once the apparatus is set up, material can flow through the machine at a rate of 5 mls/min being continuously separated. The main problem and area for further study is that of concentrating the relatively dilute fractions without undue loss.

Interferon production in leukaemia

Leucocyte interferon production in vitro and circulating interferon levels were studied in healthy subjects and in 80 patients with acute or chronic leukaemia. Circulating interferon was not found in either group. Interferon synthesis in response to a virus was normal in patients with acute leukaemia and appeared to be enhanced in some. In chronic leukaemia reduced levels were common particularly in CLL, in which condition normal results were rarely found; lymphocyte transformation to PHA was also depressed in this group. No clinical or haematological correlation with the interferon levels was found and no consistent effect of treatment was shown. The possible factors which could account for these findings and their significance in relation to pathogenesis and treatment of leukaemia are discussed.

Treatment of HBsAg-positive chronic active hepatitis with human fibroblast interferon

Two patients with HBsAg positive chronic active hepatitis have been treated with human fibroblast interferon 10(7) units daily for two weeks. Before treatment, both patients had high levels of hepatitis B surface antigen, core antibody, and DNA-binding antibody in the blood and one patient had a fourfold rise in serum AST. During treatment there was a striking fall in the core antibody titre and also in the DNA-binding antibody, which has been maintained for several months subsequently; in one patient the initially high AST level fell to normal. No significant adverse effects occurred, and these observations should encourage further trials of fibroblasts interferon in hepatitis B.

The mechanism of the inactivation of human fibroblast interferon by mechanical stress

Interferon derived from human fibroblasts is readily inactivated during agitation and filtration. This inactivation has been shown to be largely a product of mechanical stress, and has been studied in detail by subjecting interferon to controlled shear stress using a rotational viscometer. The possible mechanism of this phenomenon is discussed.

Reagents which inhibit disulphide bond formation stabilize human fibroblast interferon

Fibroblast interferon may be stabilized against many inactivating influences by the addition of certain simple sulphydryl reagents. The use of such easily removable and relatively non-toxic stabilizers should help in the preparation and purification of fibroblast interferon for clinical use.