POS0715 TREATMENT OF SLE PATIENTS WITH ZETOMIPZOMIB (KZR-616), A SELECTIVE INHIBITOR OF THE IMMUNOPROTEASOME, RESULTS IN CIRCULATING GENE EXPRESSION, PROTEIN LEVEL, AND IMMUNE CELL PHENOTYPIC CHANGES WITH POTENTIAL CORRELATIONS TO CLINICAL RESPONSE

Background

Systemic lupus erythematosus (SLE), a severe multiorgan autoimmune disease, involves dysfunction of multiple immune system components. In preclinical studies, KZR-616, a first-in-class small molecule selective inhibitor of the immunoproteasome, demonstrated pleiotropic immunomodulatory functions encompassing both innate and adaptive immune pathways1,2. In the recently completed MISSION Phase 1b trial in SLE patients (pts), KZR-616 exhibited encouraging safety, tolerability, and clinical improvements3. Preliminary biomarker analysis of the first two cohorts was previously reported4. Here, we present complete biomarker results from all cohorts in this study.

Objectives

1) To characterize biomarker changes (gene expression, circulating protein levels and immune cell phenotypes) following KZR-616 treatment. 2) To evaluate correlations between biomarker changes and treatment response to KZR-616.

Methods

The open-label Phase 1b MISSION Trial (NCT 03393013) was a 25-week trial of KZR- 616 administered subcutaneously once weekly at doses ranging from 30-75 mg for 13 weeks (W) with a 12 W follow-up. Forty-seven SLE pts with and without nephritis were enrolled with 35 completing all 25 W of study. Clinical response definitions at W13 or later were defined as either a >4 reduction of SLEDAI-2K or >50% drop in swollen joint counts (SJC) (baseline SJC>2). Biomarker samples included whole blood in RNA tubes (31 pts), cryopreserved PBMCs (15 pts), plasma (35 pts) and urine (2 pts). Whole blood RNA sequencing was performed using Illumina TruSeq. Differential expression was modelled using DESeq2. Fast pre-ranked gene set enrichment analysis (GSEA) was performed with gene sets derived from published literature. Cryopreserved PBMCs were analysed by flow cytometry to profile immune cell subtypes. Plasma protein was measured by Meso Scale Discovery (MSD) kits. Healthy volunteer (HV, N=12) samples were used to establish potential disease-related biomarker changes in patients at baseline (BL).

Results

Many gene modules were found to be altered at BL in SLE pts, relative to HV, including those representing interferon (IFN) response and B/plasma cells and changes were consistent with our prior report4. Comparisons of SLEDAI-2K responders (R) versus non-responders (NR) revealed enrichment of 193 gene modules (57 down and 136 up-regulated, padj,<0.1) at BL and 190 modules (105 down and 85 up) 4 weeks after treatment (W17). Expression of a 4-gene IFN module was enriched in SLEDAI-2K R vs NR at BL; expression of this module trended downward at W17 in R, whereas it increased over time in NR at W 5. Reduced numbers of circulating class-switched memory B cells and IgG-producing plasma cells were observed at W17 and/or W25. Plasma levels of BAFF were consistently increased at W5 but returned to BL levels by W17. Plasma levels of CD169/ SIGLEC-1, a monocyte activation marker, were higher at BL in SJC R vs. NR and were reduced after treatment in both groups. Two pts with active proliferative nephritis were enrolled into this study and both showed a reduction in levels of urine CD163 (uCD163), while plasma levels of this marker were stable.

Conclusion

Our integrative analysis indicates that KZR-616 elicits a potent effect on multiple immune pathways in SLE patients. Potential new biomarkers (gene, gene module, circulating protein) that may be useful for prediction of patient response were identified. Future biomarker studies in placebo-controlled trials may further our understanding of KZR-616 mechanism of action, patient selection and prediction of patient responses.

References

[1]Kirk, C.J. et al., Cells 2022, 11(1):9

[2]Muchamuel T, Arthritis Rheumatol. 2019; 71 (suppl 10).

[3]Furie R et al., Annals of the Rheumatic Diseases 2021;80:595-596,

[4]Fan R, et al., Arthritis Rheumatol. 2019; 71 (suppl 10).

Acknowledgements

Kezar Life Sciences acknowledges the support of site investigators and patient participants in the MISSION study.

Disclosure of Interests

Andrea Fan Shareholder of: Kezar, Employee of: Kezar, Brian Tuch Consultant of: Kezar, Tony Muchamuel Shareholder of: Kezar, Employee of: Kezar, Janet Anderl Shareholder of: Kezar, Employee of: Kezar, Richard Leff Consultant of: Kezar, Noreen Henig Shareholder of: Kezar, Employee of: Kezar, Christopher Kirk Shareholder of: Kezar, Employee of: Kezar

POS0695 KZR-616, A SELECTIVE IMMUNOPROTEASOME INHIBITOR FOR THE TREATMENT OF SYSTEMIC LUPUS ERYTHEMATOSUS: RESULTS FROM THE COMPLETED DOSE ESCALATION PHASE 1B PORTION OF THE MISSION STUDY

Background:

KZR-616 is a first-in-class selective inhibitor of the immunoproteasome, which is active in >15 autoimmune disease models, including murine models of systemic lupus erythematosus (SLE)/lupus nephritis (LN).1,2,3 Selective inhibition of the immunoproteasome modulates both innate and adaptive immune effector cells, resulting in reduced inflammatory T helper cell subsets (Th1 and Th17), increased regulatory T cells, and decreased plasma cells and autoantibodies. KZR-616 was well tolerated in two healthy volunteer studies of 100 subjects receiving up to 75 mg subcutaneously (SC). Target levels of immunoproteasome inhibition were observed at doses ≥30 mg.3,4 KZR-616 is currently in Phase 2 studies for several autoimmune indications, including the ongoing Phase 2 portion of the MISSION Study (KZR-616-002; NCT0339013) in patients with LN.

Objectives:

Results of the completed MISSION Phase 1b dose escalation portion of the study are reported.

Methods:

In the open-label, multicenter, dose escalation Phase 1b portion, SLE patients (per SLICC Classification Criteria) with SLEDAI ≥4 despite stable background immunosuppressant, anti-malarial, and/or corticosteroid therapy were administered weekly KZR-616 subcutaneously at doses of 45 mg (cohort 1), 60 mg (cohort 2), 60 mg following step-up doses of 30 mg and 45 mg (cohort 2a), 60 mg following a step-up dose of 30 mg (cohorts 2b, 2c) or 75 mg following a step-up dose of 30 mg (cohort 3) for 13 weeks with follow-up through Week 25 (W25); a lyophilized formulation was used for cohorts 2b, 2c and 3. The disease activity measures assessed were: SLEDAI-2K, Cutaneous Lupus Erythematosus Disease Area and Severity Index (CLASI), 28 tender and swollen joint counts, Physician and Patient Global Assessments, and Patient Assessment of Pain. Safety and tolerability were assessed in the safety population (patients receiving at least one dose of KZR-616).

Results:

The Phase 1b portion of MISSION enrolled 47 SLE patients, including 2 patients with active proliferative LN. The most common treatment-emergent adverse events (TEAE) were injection site reactions, which were mostly mild. Infections occurred at a low rate, and there were no reports of peripheral neuropathy, prolonged hematologic AEs, or clinically significant laboratory abnormalities. No discontinuations were observed in cohorts 2b and 2c; no serious AEs were reported in cohort 3 and TEAEs were consistent with those reported in earlier cohorts. Mean values of all measures of disease activity improved in evaluable patients who completed the 13-week treatment period, and improvements were generally maintained at W25. All patients with elevated anti-double-stranded DNA antibody (anti-dsDNA) levels at baseline (n=7) had a reduction in levels with 3 of 7 experiencing a >50% reduction in their levels. Two of two patients with active proliferative LN had a >50% reduction in UPCR and experienced reductions in SLEDAI-2K scores as well as anti-dsDNA levels. Exposure to KZR-616, similar to that reported in healthy volunteers, was dose-proportional across doses, and no accumulation was observed.

Conclusion:

KZR-616 SC, once weekly for 13 weeks up to 75 mg, appears to be safe and well-tolerated in patients with active SLE on stable background therapy in the MISSION Phase 1b. At doses ≥45mg, efficacy was noted, including improvements in proteinuria in two of two patients with LN and serologic improvement in all 7 patients with quantifiable levels of anti-dsDNA antibodies at baseline. KZR-616 60 mg SC weekly for 24 weeks is currently being evaluated in the MISSION Phase 2 in patients with LN. Based on the results of MISSION, inhibition of the immunoproteasome with KZR-616 represents a novel strategy to treat autoimmune diseases.

References:

[1]Basler M et al. Clin Exp Rheumatol 2015 (suppl 92);S74.

[2]Muchamuel T et al. Ann Rheumatol Dis 2018;77(suppl 2);685.

[3]Muchamuel T et al. ASN 2020 Virtual Conference.

[4]Snyder B et al. ACR/ARP 2019 Annual Meeting.

[5]Fan RA et al. ACR/ARP 2019 Annual Meeting.

Acknowledgements:

Kezar Life Sciences acknowledges the support of site investigators and patient participants in the MISSION study

Disclosure of Interests:

Richard Furie Consultant of: Genentech;Kezar Life Sciences, Grant/research support from: Kezar Life Sciences, SV Parikh Consultant of: Aurinia Pharmaceuticals, BMS, GlaxoSmithKline, and Kezar Life Sciences, Grant/research support from: Aurinia Pharmaceuticals;EMD-Serono, Jinhai Wang Shareholder of: Kezar Life Sciences, Employee of: Kezar Life Sciences, Darrin Bomba Shareholder of: Kezar Life Sciences, Employee of: Kezar Life Sciences, Richard Leff Employee of: Kezar Life Sciences [part-time], Christopher Kirk Shareholder of: Kezar Life Sciences, Employee of: Kezar Life Sciences -- full-time employee, Noreen Henig Shareholder of: Kezar Life Sciences, Employee of: Kezar Life Sciences

AB0373 TREATMENT OF SLE WITH THE IMMUNOPROTEASOME INHIBITOR KZR-616: RESULTS FROM THE FIRST 4 COHORTS OF THE MISSION STUDY, AN OPEN-LABEL PHASE 1B DOSE ESCALATION TRIAL

Background:

Non-specific proteasome inhibitors, such as bortezomib (BTZ), target the constitutive proteasome and immunoproteasome and are approved treatments for multiple myeloma1. BTZ has also been used to treat systemic lupus erythematosus (SLE) and lupus nephritis (LN); however, treatment emergent adverse events (TEAEs), such as gastrointestinal (GI) effects, hematologic abnormalities, asthenia and peripheral neuropathy, limit its use as a long-term treatment option for chronic autoimmune disease2. KZR-616 is a first-in-class selective immunoproteasome inhibitor and is highly active in murine SLE3. Subcutaneous (SC) administration of KZR-616 (30 and 45 mg weekly [QW]) was demonstrated as safe and well-tolerated, and successfully achieved target levels of immunoproteasome inhibition in healthy volunteers4, 5.

Objectives:

We report the preliminary safety and efficacy of KZR-616 in the first 4 cohorts of the Phase 1b portion of Study KZR-616-002 in patients with active SLE (NCT03393013).

Methods:

SLE patients (per SLICC Classification Criteria) with SLEDAI ≥4 despite stable background immunosuppressant, anti-malarial, and/or corticosteroid (≤20 mg prednisone equivalent) therapy in this open-label multicentric dose-escalation trial received KZR-616 at doses of 45mg (Cohort 1), 60mg (Cohort 2), or 30mg with escalation to 60mg (Cohorts 2a and 2b) SC weekly through Week 13 (W13) with 12 weeks of follow-up. Efficacy measures included SLEDAI, Cutaneous Lupus Erythematous Disease Area and Severity Index, 28 tender and swollen joint counts, Physicians Global Assessment, Patient Global Assessment, and Patient Assessment of Pain, in evaluable patients (those who received ≥1 month of KZR-616).

Results:

As of 16 January 2020, 33 patients had enrolled and received at least 1 dose of KZR-616. The majority of TEAEs have been mild or moderate with no reported peripheral neuropathy, prolonged GI-related AEs, and no clinically significant laboratory AEs. There were 3 treatment emergent SAEs, one each of thrombotic microangiopathy (Cohort 2), localized herpes zoster (Cohort 2a), and systemic inflammatory response syndrome (Cohort 2a) with the latter 2 patients completing the full 13 weeks of treatment after resolution. When compared to baseline, improvement in all measures of disease activity were seen at W13 and maintained or improved during the follow-up period, and 94% of evaluable patients had improvements on at least 2 measures/assessments of disease activity. A single patient with active class IV/V nephritis was enrolled on prednisone 10 mg, leflunomide 10 mg, and hydroxychloroquine 200mg/day; nephrotic-range proteinuria at baseline (3.85 g/day) decreased to 0.6 g/day 4 weeks after the last dose of KZR-616.

Conclusion:

Weekly subcutaneous administration of KZR-616 at 45 and 60 mg was safe and well-tolerated. Evidence of disease suppression at W13 in active SLE patients on stable background therapy was observed. In addition, one study participant with active proliferative nephritis was enrolled with significant reduction in proteinuria. The Phase 2 portion of this study in active proliferative LN is open for enrollment.

References:

[1]Scott K.et al.Cochrane Database Syst Rev 2016;4:CD010816

[2]Alexander Tet al.Ann Rheum Dis 2015;74: 1474–8

[3]Muchamuel T.et al.Ann Rheum Dis 2018;77: A685

[4]Lickliter J.et al.Ann Rheum Dis 2018;77: A1413

[5]Furie Ret al.Ann Rheum Dis 2019;78: A776

Disclosure of Interests:

Richard Furie Grant/research support from: AstraZeneca, Biogen, Consultant of: AstraZeneca, Biogen, SV Parikh Grant/research support from: Aurinia Pharmaceuticals, EMD-Serono, Consultant of: Aurinia, BMS, GSK, Adonis Maiquez: None declared, Amber Khan: None declared, Orlando Moreno: None declared, Miguel Soneira: None declared, Christopher Kirk Shareholder of: Kezar Life Sciences, LLC, Employee of: Kezar Life Sciences, LLC, Darrin Bomba Shareholder of: Kezar Life Sciences, LLC, Employee of: Kezar Life Sciences, LLC, Ken Harvey Shareholder of: Kezar Life Sciences, LLC, Employee of: Kezar Life Sciences, LLC, Mary Katherine Farmer Shareholder of: Kezar Life Sciences, Employee of: Kezar Life Sciences

Large-scale discovery of novel genetic causes of developmental disorders

Despite three decades of successful, predominantly phenotype-driven discovery of the genetic causes of monogenic disorders, up to half of children with severe developmental disorders of probable genetic origin remain without a genetic diagnosis. Particularly challenging are those disorders rare enough to have eluded recognition as a discrete clinical entity, those with highly variable clinical manifestations, and those that are difficult to distinguish from other, very similar, disorders. Here we demonstrate the power of using an unbiased genotype-driven approach to identify subsets of patients with similar disorders. By studying 1,133 children with severe, undiagnosed developmental disorders, and their parents, using a combination of exome sequencing and array-based detection of chromosomal rearrangements, we discovered 12 novel genes associated with developmental disorders. These newly implicated genes increase by 10% (from 28% to 31%) the proportion of children that could be diagnosed. Clustering of missense mutations in six of these newly implicated genes suggests that normal development is being perturbed by an activating or dominant-negative mechanism. Our findings demonstrate the value of adopting a comprehensive strategy, both genome-wide and nationwide, to elucidate the underlying causes of rare genetic disorders.

An evaluation of UK secondary data sources for the study of childhood obesity, physical activity and diet

BACKGROUND

This study assesses the potential of secondary datasets for measuring recent and future trends in childhood obesity, physical activity and diet in the UK, at national, regional and sub-regional levels, and in relation to inequalities.

METHODS

Relevant datasets were identified using online searches; they were excluded if they had low sample sizes, were assembled prior to 1990 or on only one occasion, were not potentially accessible, or were limited to a specific population. Remaining datasets were assessed according to content, sampling frame and size, timing and ability to be used to assess inequalities and regional trends.

RESULTS

A total of 96 datasets were identified, but only 11 had the potential to be used to assess trends. Eight of these contained data on physical activity, 8 on diet and 3 on obesity. The period over which trends might be assessed varied from 2 years to over 10, with over half of the datasets expected to continue data collection into the future. Most had the potential to be used to assess inequalities and also regional and sub-regional level trends, albeit with relatively small sample sizes. There were some limitations to the datasets, such as non-objective measures of diet and physical activity and, in some, low response rates, which would require further consideration when utilizing individual datasets.

CONCLUSIONS

Awareness of the potential of secondary datasets for monitoring trends in childhood obesity should be raised, alongside the financial and intellectual capacity to enhance and exploit them.

Analysis of a care planning intervention for reducing depression in older people in residential care

Approximately 40% of older people in residential care have significant symptoms of depression. A training and care-planning approach to reducing depression was implemented for 114 depressed residents living in 14 residential care homes in North Yorkshire, UK. Care staff were offered brief mental health training by community mental health teams for older people. They were then assigned to work individually with residents in implementing the care-planning intervention, which was aimed at alleviating depression and any health, social or emotional factors that might contribute to the resident's depression. Clinically significant improvements in depression scores were associated with implementation of the care-planning intervention as evidenced by changes in scores on the Geriatric Mental State Schedule-Depression Scale. There was evidence of an interaction between the power of the intervention and degree of dementia. These improvements were not accounted for by any changes in psychotropic medication. The training was highly valued by care staff and heads of homes, and they considered that the care-planning intervention represented an improvement in quality of care for all residents, irrespective of levels of dementia. Staff also reported improvements in morale and increased confidence in the caring role as a result of their participation. The limitations of this study are discussed. On the basis of a growing body of evidence, it is argued that there is an urgent need for a suitably powered randomised controlled trial and economic evaluation, to test the cost-effectiveness of personalised care planning interventions aimed at reducing depression in older people in residential care.

Solution-phase, parallel synthesis and pharmacological evaluation of acylguanidine derivatives as potential sodium channel blockers

Solution-phase synthesis of various acylguanidine derivatives and the evaluation of a small library of compounds as potential sodium channel blockers are described.

Deliberate self-harm and antidepressant drugs. Investigation of a possible link

BACKGROUND

It is not clear if the frequency of deliberate self-harm (DSH) is the same in patients taking different pharmacological classes of antidepressant drugs.

AIMS

To compare the frequency of DSH in patients who had been prescribed a tricyclic antidepressant (TCA) or a selective serotonin reuptake inhibitor (SSRI) prior to the DSH event.

METHOD

This was a prospective study in 2776 consecutive DSH cases attending an accident and emergency department. The incidence of DSH in TCA-treated cases and SSRI-treated cases is expressed as number of DSH events per 10 000 prescriptions of each antidepressant.

RESULTS

Significantly more DSH events occurred following the prescription of an SSRI than that of a TCA (P<0.001). The occurrence of DSH was highest with fluoxetine and lowest with amitriptyline.

CONCLUSIONS

Merely prescribing safer-in-overdose antidepressants is unlikely to reduce the overall morbidity from DSH.

Methods for evaluating treatment of uroliths

Formation of uroliths is not a disease but rather a complication of several disorders. Some disorders can be identified and corrected (e.g., infection-induced struvite urolith formation), and some can be identified but not corrected (e.g., hyperuricosuria occurring in Dalmatians that form ammonium urate uroliths), although for others, the underlying etiopathogenesis is not known (e.g., calcium oxalate urolith formation in Miniature Schnauzers). A common denominator of these disorders is that from time to time, they can create oversaturation of urine with one or more crystal precursors, resulting in formation of crystals. To develop rational and effective approaches to treatment, abnormalities that promote urolith formation must be identified with the goal of eliminating or modifying them. It is therefore important to understand several basic concepts associated with urolithiasis.

Recombinant human glial growth factor 2 (rhGGF2) improves functional recovery of crushed peripheral nerve (a double-blind study)

This in vivo double-blind study evaluated the effect of recombinant human glial growth factor 2 (rhGGF2), a Schwann cell mitogen, on the recovery of motor function of rat sciatic nerve following crush injury. Seventy three rats were divided into three groups. Group I (n=5), sham operated; Groups II (n=34) and III (n=34) received a 100 g crush load for 2 h over a 5 mm segment of the sciatic nerve. Group III was treated with 1 mg/kg rhGGF2, via subcutaneous injection one day before nerve crush and daily for the following four days. Group II received an equivalent volume of saline as a control. Motor functional recovery was assessed by calculating the sciatic functional index (SFI) and the recovery rate of tetanic contractile force of the extensor digitorum longus (EDL) muscle. Recovery of nerve function was evident at day 11 after crush in the rhGGF2-treated animals, whereas the nerves in controls were still paralyzed. The rhGGF2-treated animals showed a significant improvement of the SFI between days 11-21 postoperatively when compared to controls. The isometric tetanic contractile force was stronger in the rhGGF2-treated group than in controls, with a significant difference at 40 to 70 Hz stimulus frequencies on day 4. Correlation analysis showed that tetanic contractile force had a linear correlation with the SFI. Histologic assessment indicated that the rhGGF2-treated animals showed less severe degeneration and earlier robust remyelination of axons than controls. The results suggest that treatment with rhGGF2 is effective in promoting nerve regeneration as seen in measurements of functional recovery and qualitative assessment of nerve morphology. The mechanism of GGF's protective effect may be related to its direct action on Schwann cells, stimulating their mitosis as well as inducing neurotrophic factors essential to neuronal maintenance and repair.

Identification of a neuregulin and protein-tyrosine phosphatase response element in the nicotinic acetylcholine receptor epsilon subunit gene: regulatory role of an Rts transcription factor

At the neuromuscular synapse, innervation induces endplate-specific expression of adult-type nicotinic acetylcholine receptors by selective expression of their subunit-encoding genes (alpha2betaepsilondelta) in endplate-associated myonuclei. These genes are specifically regulated by protein-tyrosine phosphatase (PTPase) activity. In addition, neuregulin/acetylcholine-receptor-inducing activity, a nerve-derived factor that stimulates nicotinic acetylcholine receptor synthesis, induces adult-type specific epsilon subunit gene expression via activation of a Ras/mitogen-activated protein kinase pathway. However, the DNA regulatory elements and the binding proteins that mediate PTPase and neuregulin-dependent gene expression remain unknown. Herein we report that PTPase, neuregulin, and Ras-dependent regulation of the epsilon subunit gene map to a 15-bp promoter sequence. Interestingly, this same 15-bp sequence appears to be necessary for low epsilon subunit gene expression in extrajunctional regions of the muscle fiber. Site-directed mutagenesis of a putative Ets binding site located within this 15-bp sequence, reduced PTPase, neuregulin, and Ras-dependent regulation. Overexpression of the rat muscle Ets-2 transcription factor resulted in a sequence-specific induction of epsilon subunit promoter activity. Further, a dominant negative mutant of Ets-2 abolished neuregulin-dependent induction of epsilon subunit gene expression. Thus, these results indicate a crucial role for the 15-bp element in determining synapse-specific and neuregulin-mediated motor neuron control of epsilon subunit gene expression and suggest the participation of Ets transcription factor(s) in this control.

Kinetic analysis of drug cleavage of closed-circular DNA

Various cleavage agents interact with circular double-stranded DNA molecules to convert the closed-circular form (form-I) to the open-circular (form-II) and linear (form-III) forms, and ultimately to small DNA fragments. The various cutting processes which take place in the DNA pool are here analyzed kinetically, and, by solving the kinetic equations, expressions are derived for the amounts of the closed-circular, open-circular, and linear forms of DNA as a function of reaction time and concentration of cleavage agent. Conversions between subspecies of forms II and III, differing in numbers of internal cuts, are taken into account. The only assumption required to solve the kinetic equations is that the concentration of cleavage agent obeys [D] = D0 f(t) where the function of time f(t) is independent of D0, the initial concentration of cleavage agent. By choosing parameters in the expressions for the calculated amounts of forms I, II and III to give the best fit to the measured amounts, one obtains information about the rates and rate constants for the conversions. The rate constants in turn give important information about the specificity and mechanism of action of the cleavage agents. The analysis is applied to the cleavage of pBR322, SV-40 and PM2 DNAs by DNase I, Fe-EDTA, and the antitumor agents calicheamicin and bleomycin. Cleavage rate constants are derived and discussed for these systems.

Stimulation of myogenic differentiation by a neuregulin, glial growth factor 2. Are neuregulins the long-sought muscle trophic factors secreted by nerves?

It has long been known that nerves stimulate growth and maintenance of skeletal muscles in ways not dependent on physical contacts, but numerous attempts to identify and characterize the myotrophic agent(s) secreted by nerves have been unsuccessful. We here suggest that products of the neuregulin gene may be these agents. The neuregulins are a family of proteins made by alternative splicing of a single transcript to give as many as 15 protein products. One member of this family, glial growth factor 2 (rhGGF2) is a very potent stimulator of myogenesis in L6A1 myoblasts, giving a maximal stimulation of cell fusion and creatine kinase elevation at a concentration of 1 ng/ml (18 pM). The stimulation of myogenesis is not rapid, but it is prolonged, continuing over a period of at least 6 days. The effects of rhGGF2 are additive with those of insulin-like growth factor I (IGF-I) or its analog R3-IGF-I, suggesting that the actions of these two myotrophic agents differ in at least one rate-limiting step. We have observed one possible difference; unlike the IGFs, rhGGF2 does not induce elevation of the steady state level of myogenin mRNA.

Changes in milk composition during lactation in three species of insectivorous bats

Changes in milk composition are described for three species of free-ranging insectivorous bats (Myotis lucifugus, M. velifer, and Tadarida brasiliensis) from early to mid (peak) lactation. Dry matter and energy concentrations in milk increased from early to mid-lactation. In M. lucifugus and T. brasiliensis, but not M. velifer, these increases were due largely to a rise in fat concentration, since protein and carbohydrate remained relatively constant. Energy content of milk (kJ.g-1) for each species from early through mid-lactation was related to dry matter (DM) as follows: M. lucifugus (y = 0.31 DM-0.32, r2 = 0.68), M. velifer (y = 0.48 DM-5.08, r2 = 0.99), and T. brasiliensis (y = 0.37 DM-1.51, r2 = 0.61). Comparison of the effect of sampling method on milk composition of T. brasiliensis indicated that fat, dry matter, and energy concentrations increased significantly from pre-dawn to pre-noon samples. Relatively high fat and low water levels in T. brasiliensis milk may reflect the limited access that lactating females have to free water, as well as need to minimize mass of stored milk during long foraging trips. Conversely, lower fat concentrations and higher water levels in milk in M. lucifugus and M. velifer may relate to the propensity for colonies of these two species to roost and forage near bodies of water. In addition, differences in milk fat concentrations observed among the three species may correlate to daily suckling schedules.(ABSTRACT TRUNCATED AT 250 WORDS)

PCR generation of large amounts of purified DNA

The preparation and purification of PCR generated DNA fragments suitable for footprinting and classical drug binding studies is described. One of the fragments, a 214-mer derived from pBR322 DNA exhibits a biphasic melting profile. This behavior appears to be due to a non-random distribution of base pairs within the fragment causing a region rich in AT base pairs to melt prior to a segment having a high concentration of GC base pairs. The usefulness of large amounts of PCR generated DNA for footprinting and optical binding studies involving drugs is also presented and discussed.

Glial growth factors are alternatively spliced erbB2 ligands expressed in the nervous system

Glial growth factors, proteins that are mitogenic for Schwann cells, and several ligands for the p185erbB2 receptor, are products of the same gene. Alternative splicing of the messenger RNA generates an array of putative membrane-attached, intracellular and secreted signalling proteins, at least some of which are expressed in the developing spinal cord and brain. These factors are probably important in the development and regeneration of the nervous system.

Neuroleptic malignant syndrome: a preventive program

Neuroleptic Malignant Syndrome is a very serious side effect of antipsychotic medications. The paper describes a preventative program which was instituted in an inpatient unit of a provincial psychiatric hospital. There have been no mortalities from Neuroleptic Malignant Syndrome (NMS) during this program. A suspicion of NMS by clinical evaluation and laboratory tests resulted in prompt management. The recommended management plan is described.

Intracavitary cisplatin chemotherapy experience with six dogs

Six dogs with a median age of 7 years (range = 5-14 years) were presented for signs referable to thoracic or abdominal effusion associated with neoplasia of the body cavities. Intracavitary cisplatin was administered at 50 mg/m2 every 4 weeks for a median of 2.5 treatments (mean = 3, range = 1-6). Three dogs with pleural mesothelioma had complete resolution of effusion for 289, 129, and greater than 306 days without evidence of tumor growth. Resolution of effusion occurred after one treatment in two dogs and after two treatments in one dog. In three dogs with carcinomatosis of unknown origin, complete responses was seen in two dogs after one treatment for 255 and greater than 807 days, respectively. Intracavitary chemotherapy with cisplatin was associated with palliation and control of malignant pleural and/or abdominal effusion in five of six dogs. Toxicity was minimal, and this method of therapy should be further explored in dogs with similar malignancies.

Prospective payment for rehabilitation: effects on hospital readmission, home care, and placement

Suspected benefits of a prospective payment system (PPS) in which hospitals are paid by diagnosis-related groups (DRGs) are that hospital lengths of stay and costs may be reduced. The US Department of Veterans Affairs is one of the first agencies to adopt PPS funding for rehabilitation; this early adoption of PPS provides a unique opportunity to test for both beneficial and adverse outcomes. This study compared hospital stay, readmission rate, and incidence of nursing home placement before and after introduction of PPS on a 22-bed rehabilitation service. Hospital stay decreased from 29.3 days to 26.4 days, but 64% more patients were discharged to nursing homes. Findings suggest that PPS may overlook home care in favor of placement, which neutralizes the cost benefits of the proposed reimbursement system. Further research on the effects of PPS is needed to determine (1) impact on clinical aspects of rehabilitation and (2) whether other funding mechanisms are more appropriate.

Effects of prospective payment financing on rehabilitation outcome

A suspected benefit of paying hospitals per diagnostic related groups (DRGs), i.e. the prospective payment system (PPS), is that lengths of stay (LOS) and costs may be reduced. A potential adverse effect is that providers may discharge patients to reduce costs regardless of clinical consequence. The Veterans Administration (VA) is one of the first agencies to adopt PPS for rehabilitation. This study analyzed the effects of PPS on LOS, readmission rate, nursing home placement (NHP), and referral for Home Health Care (HHC) on a 22 bed rehabilitation unit. One hundred and eighty-seven patients discharged in 1987, prior to the program, were compared (using t-tests) with 215 discharges in 1988, after PPS was established. There were no significant differences in demographics, self-care ability, or in readmissions. Referrals for HHC decreased significantly. LOS decreased from 29.3 days (SD = 16.4) in 1987 to 26.4 days (SD = 14.1) in 1988 (t = 5.3, p less than 0.01). However, 24 more patients were discharged to nursing homes in 1988 (N = 54, 25%) than in 1987 (N = 30, 16%), which represents an increase of 64% (p less than 0.05). Findings suggest that PPS may defer home care in favor of placement. Clinicians need to assess whether reducing inpatient LOS justifies increased use of nursing homes. Further research on the effects of PPS is needed to determine: (a) impact on clinical aspects of rehabilitation; and (b) if other funding mechanisms are more appropriate.

Electrophysiological responses to dopamine of rat hypophysial cells in lactotroph-enriched primary cultures

1. Cells from 14-day-old and lactating female rat pituitary glands were dissociated, separated and enriched on a continuous gradient of bovine serum albumin at unit gravity. They were maintained for at least 6 days in culture before perifusion and electrophysiological experiments were performed. 2. Immunofluorescent staining of the resulting gradient fractions (numbered F2 to F9) from both groups of animals indicated that the majority of lactotrophs were located in the light fractions (F3-F4). However, a second population of lactotrophs was observed in the heavy fractions (F7-F9) isolated from lactating females. 3. Basal secretion rates of prolactin were in the order of 2-40 ng 2 min-1 10(6) cells-1 and were inhibited by dopamine in a dose-dependent manner. 4. According to their electrophysiological properties, cells from 14-day-old females (first group) were categorized as follows: (1) inexcitable cells, which displayed a low resting potential of about -35 mV (39% of cells tested, n = 118); and (2) excitable cells, which displayed either triggered or spontaneous action potentials and resting membrane potentials higher than -50 mV (61% of cells tested, n = 185). 5. In the light fraction from lactating females (second group), the majority of the cells were excitable (70%) and showed high resting membrane potentials (-50 to -55 mV) and 15% of these cells displayed spontaneous action potentials. 6. Heavy fractions (third group) contained a high percentage of non-spontaneous but excitable cells (80% of the cells tested, n = 65). These cells were able to elicit action potentials after the cessation of hyperpolarizing current pulses ('off' potentials). 7. Action potentials were insensitive to the sodium channel blocker, tetrodotoxin (TTX; 5 x 10(-6) M) but were reversibly blocked by calcium channel blockers such as cobalt, manganese and cadmium (10 mM). 8. In excitable cells from the three groups, dopamine (10(-7) M) induced a hyperpolarizing response due to an increase of the membrane conductance. During this response, action potentials were inhibited. It was shown that this was not a direct effect of dopamine. The reversal potential of the dopamine-induced response in these cells was found to be at -100 mV. This value was shifted to more positive potentials (-50 mV) when high-potassium medium was used (56 mM). 9. In non-excitable cells (first group), dopamine (10(-7) M) induced a hyperpolarizing response due to a decrease of the membrane conductance.(ABSTRACT TRUNCATED AT 400 WORDS)

Torpedo electromotor system development: neuronal cell death and electric organ development in the fourth branchial arch

The fourth branchial arch of Torpedo marmorata has been examined at the light and electron microscopic level during development. Of interest was the determination of the extent of electric organ tissue reported to be present in this arch and its possible relationship to electromotoneuron cell death in the electric lobes. The main electric organ of the torpedo is derived from the hyoid and first three branchial arches and is innervated by four major electromotor nerves. Extensive electromotoneuron cell death occurs in the electric lobes and most notably in the posterior poles. This feature could be due to a tendency for these neurons to innervate the fourth branchial arch where little or no electric tissue is formed. Our findings support this conclusion but are not entirely consistent with the idea that a population mismatch has occurred. This is because cell death precedes the genesis of the target cells. The presence of innervated differentiated electric tissue in this arch is also reported, leading to the conclusion that Torpedo marmorata possesses an accessory electric organ.

Brain stem projections in the pulvinar-lateralis posterior complex of the cat

The present experiments were undertaken to define the areas of projection of pretectum and superior colliculus to the pulvinar and n. lateralis posterior, respectively, and to define other brain stem structures projecting to these thalamic nuclei in cats. For this purpose of technique of retrograde transport of horseradish peroxidase (HRP) has been used. After injection of the enzyme in the pulvinar, neurons were labeled in all subdivisions of the pretectal area. The majority of the labeled cells were located in the n pretectalis anterior pars compacta and area pretectalis medialis. Neurons projecting to the pulvinar were also found in the periaqueductal gray, reticular formation and locus coeruleus. When HRP was injected in the n. lateralis posterior, labeled neurons were present in the II and III subdivisions of the second layer of the superior colliculus. The location of these cells shifted from medial to lateral as the injections were shifted from posterior to anterior within the lateralis posterior. Neurons projecting to this nucleus were also present in the intermediate layers of the superior colliculus, lateral hypothalamus and parabigeminal nucleus. The possible role of the pretectal area and superior colliculus in mediating somesthetic input to the pulvinar and lateralis posterior, respectively, and the role of these structures in the control of ocular movements, are discussed.

Aminopeptidase activity associated with purified murine leukaemia viruses

Rauscher leukaemia virus (RLV), extensively purified by rate and density gradient centrifugation procedures, exhibited aminopeptidase (AP) activity. The amount of virion activity was about 0.005 times the specific activity of purified hog kidney aminopeptidase M (EC 3.4.11.2). The activity was also found in purified Moloney and Gross leukaemia viruses, but not in comparable gradient fractions of uninfected JLSV-9 cells. Furthermore replacement of serum by bovine serum albumin in the growth medium of virus producing cells did not affect the AP activity. These results indicate that murine leukaemia viruses (MuLV) possess a tightly bound AP activity which is present as a minor component of the virion preparation and is probably not due to host cell membrane or serum contamination. Characterization of the pH optimum and substrate specificity show the MuLV aminopeptidase activity is similar to but different from both hog kidney, leucine aminopeptidase (EC 3.4.11.1) and aminopeptidase M (EC 3.4.11.2).

Primary psychiatric illness in a neurological out-patient department in North East England. An assessment of symptomatology

A total of 2,716 patients attended a neurological out-patient clinic in North East England between May 1970 and May 1974. The symptomatology of 358 patients with primary psychiatric illness has been analyzed in a retrospective study. There were 172 symptom wordings and these were grouped in 18 headings. The most common symptoms were headache, dizziness and pain in the body. The presenting symptoms were analyzed with reference to age, sex, pattern of referral, diagnostic category and method of disposal. Aspects of non-organic disease in a neurological clinic are discussed.

Medical records, medical audit, and community hospitals

A survey of community hospitals suggests a need for improving medical records and communications and introducing review procedures. A new and extended system based on an A4 size unit record is described. The benefits of a medical audit procedure in which all general practitioners and senior nurses participate are discussed.

Management and advice at the grass roots

The new management structure of the National Health Service leaves a gap between multidisciplinary management at district level and the multiprofessional clinical teams caring for patients. This gap is not satisfactorily bridged by single-profession sector management or existing advisory machinery. This is most clearly seen for community services, and experience of a possible solution in an experimental community hospital setting is described.