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Summary: In May 2017 a patient attended the emergency department at a hospital in England, with a presumed allergic reaction. He was subsequently diagnosed with measles. There were seven further confirmed cases, five of whom had received two doses of MMR vaccine. This outbreak highlights the importance of not relying on vaccination status to rule out the diagnosis of measles. Epidemiological investigations of this outbreak were particularly challenging due to the highly infectious nature of the measles virus, and prevented full elucidation of either the source of this outbreak or the transmission pathways. Keywords: Measles, Outbreak, Rash, Healthcare workers, MMR, Measles vaccine

Proprotein convertase subtilisin kexin type 9 (PCSK9) inhibits the clearance of low-density lipoprotein (LDL) cholesterol (LDL-C) from plasma by directly binding with the LDL receptor (LDLR) and sending the receptor for lysosomal degradation. As the interaction promotes elevated plasma LDL-C levels, and therefore a predisposition to cardiovascular disease, PCSK9 has attracted intense interest as a therapeutic target. Despite this interest, an orally bioavailable small-molecule inhibitor of PCSK9 with extensive lipid-lowering activity is yet to enter the clinic. We report herein the discovery of NYX-PCSK9i, an orally bioavailable small-molecule inhibitor of PCSK9 with significant cholesterol-lowering activity in hyperlipidemic APOE∗3-Leiden.CETP mice. NYX-PCSK9i emerged from a medicinal chemistry campaign demonstrating potent disruption of the PCSK9-LDLR interaction in vitro and functional protection of the LDLR of human lymphocytes from PCSK9-directed degradation ex vivo. APOE∗3-Leiden.CETP mice orally treated with NYX-PCSK9i demonstrated a dose-dependent decrease in plasma total cholesterol of up to 57%, while its combination with atorvastatin additively suppressed plasma total cholesterol levels. Importantly, the majority of cholesterol lowering by NYX-PCSK9i was in non-HDL fractions. A concomitant increase in total plasma PCSK9 levels and significant increase in hepatic LDLR protein expression strongly indicated on-target function by NYX-PCSK9i. Determinations of hepatic lipid and fecal cholesterol content demonstrated depletion of liver cholesteryl esters and promotion of fecal cholesterol elimination with NYX-PCSK9i treatment. All measured in vivo biomarkers of health indicate that NYX-PCSK9i has a good safety profile. NYX-PCSK9i is a potential new therapy for hypercholesterolemia with the capacity to further enhance the lipid-lowering activities of statins.

Background: Human serum albumin (HSA) is the most abundant plasma protein and is sensitive to glycation in vivo. The chronic hyperglycemic conditions in patients with diabetes mellitus (DM) induce a nonenzymatic Maillard reaction that denatures plasma proteins and forms advanced glycation end products (AGEs). HSA-AGE is a prevalent misfolded protein in patients with DM and is associated with factor XII activation and downstream proinflammatory kallikrein-kinin system activity without any associated procoagulant activity of the intrinsic pathway., Objectives: This study aimed to determine the relevance of HSA-AGE toward diabetic pathophysiology., Methods: The plasma obtained from patients with DM and euglycemic volunteers was probed for activation of FXII, prekallikrein (PK), and cleaved high-molecular-weight kininogen by immunoblotting. Constitutive plasma kallikrein activity was determined via chromogenic assay. Activation and kinetic modulation of FXII, PK, FXI, FIX, and FX via in vitro-generated HSA-AGE were explored using chromogenic assays, plasma-clotting assays, and an in vitro flow model using whole blood., Results: Plasma obtained from patients with DM contained increased plasma AGEs, activated FXIIa, and resultant cleaved cleaved high-molecular-weight kininogen. Elevated constitutive plasma kallikrein enzymatic activity was identified, which positively correlated with glycated hemoglobin levels, representing the first evidence of this phenomenon. HSA-AGE, generated in vitro, triggered FXIIa-dependent PK activation but limited the intrinsic coagulation pathway activation by inhibiting FXIa and FIXa-dependent FX activation in plasma., Conclusion: These data indicate a proinflammatory role of HSA-AGEs in the pathophysiology of DM via FXII and kallikrein-kinin system activation. A procoagulant effect of FXII activation was lost through the inhibition of FXIa and FIXa-dependent FX activation by HSA-AGEs., Competing Interests: Declaration of competing interests There are no competing interests to disclose., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: Economic evaluations of nutrition-sensitive agriculture (NSA) interventions are scarce, limiting assessment of their potential affordability and scalability., Objectives: We conducted cost-consequence analyses of 3 participatory video-based interventions of fortnightly women's group meetings using the following platforms: 1) NSA videos; 2) NSA and nutrition-specific videos; or 3) NSA videos with a nutrition-specific participatory learning and action (PLA) cycle., Methods: Interventions were tested in a 32-mo, 4-arm cluster-randomized controlled trial, Upscaling Participatory Action and Videos for Agriculture and Nutrition (UPAVAN) in the Keonjhar district, Odisha, India. Impacts were evaluated in children aged 0-23 mo and their mothers. We estimated program costs using data collected prospectively from expenditure records of implementing and technical partners and societal costs using expenditure assessment data collected from households with a child aged 0-23 mo and key informant interviews. Costs were adjusted for inflation, discounted, and converted to 2019 US$., Results: Total program costs of each intervention ranged from US$272,121 to US$386,907. Program costs per pregnant woman or mother of a child aged 0-23 mo were US$62 for NSA videos, US$84 for NSA and nutrition-specific videos, and US$78 for NSA videos with PLA (societal costs: US$125, US$143, and US$122, respectively). Substantial shares of total costs were attributable to development and delivery of the videos and PLA (52-69%) and quality assurance (25-41%). Relative to control, minimum dietary diversity was higher in the children who underwent the interventions incorporating nutrition-specific videos and PLA (adjusted RRs: 1.19 and 1.27; 95% CIs: 1.03-1.37 and 1.11, 1.46, respectively). Relative to control, minimum dietary diversity in mothers was higher in those who underwent NSA video (1.21 [1.01, 1.45]) and NSA with PLA (1.30 [1.10, 1.53]) interventions., Conclusion: NSA videos with PLA can increase both maternal and child dietary diversity and have the lowest cost per unit increase in diet diversity. Building on investments made in developing UPAVAN, cost-efficiency at scale could be increased with less intensive monitoring, reduced startup costs, and integration within existing government programs. This trial was registered at clinicaltrials.gov as ISRCTN65922679., (© The Author(s) 2022. Published by Oxford University Press on behalf of the American Society for Nutrition.)

Objectives: Randomization can be used as an instrumental variable (IV) to account for unmeasured confounding when seeking to assess the impact of noncompliance with treatment allocation in a randomized trial. We present and compare different methods to calculate the treatment effect on a binary outcome as a rate ratio in a randomized surgical trial., Study Design and Setting: The effectiveness of peeling versus not peeling the internal limiting membrane of the retina as part of the surgery for a full thickness macular hole. We compared the IV-based estimates (nonparametric causal bound and two-stage residual inclusion approach [2SRI]) with standard treatment effect measures (intention to treat, per protocol and treatment received [TR]). Compliance was defined in two ways (initial and up to the time point of interest). Poisson regression was used for the model-based approaches with robust standard errors to calculate the risk ratio (RR) with 95% confidence intervals., Results: Results were similar for 1-month macular hole status across methods. For 3- and 6-month macular hole status, nonparametric causal bounds provided a narrower range of uncertainty than other methods, though still had substantial imprecision. For 3-month macular hole status, the TR estimate was substantially different from the other point estimates., Conclusion: Nonparametric causal bound approaches are a useful addition to an IV estimation approach, which tend to have large levels of uncertainty. Methods which allow RRs to be calculated when addressing noncompliance in randomized trials exist and may be superior to standard estimates. Further research is needed to explore the properties of different IV methods in a broad range of randomized controlled trial scenarios., (Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: In previous systematic reviews (predominantly of randomized controlled trials), pulmonary rehabilitation (PR) has been shown to reduce hospital admissions for acute exacerbations of COPD (AECOPD). However, findings have been less consistent for cohort studies. The goal of this study was to compare rates of hospitalized and general practice (GP)-treated AECOPD prior to and following PR., Methods: Using anonymized data from the Clinical Practice Research Datalink and Hospital Episode Statistics, hospital admissions and GP visits for AECOPD were compared 1 year prior to and 1 year following PR in patients referred for PR. Exacerbation rates were also compared between individuals eligible and referred for PR vs those eligible and not referred., Results: A total of 69,089 (64%) of the patients with COPD in the cohort were eligible for PR. Of these, only 6,436 (9.3%) were recorded as having been referred for rehabilitation. A total of 62,019 (89.8%) were not referred, and 634 (0.98%) declined referral. When combining GP and hospital exacerbations, patients who were eligible and referred for PR had a slightly higher but not statistically significant exacerbation rate (2.83 exacerbations/patient-year; 95% CI, 2.66-3.00) than those who were eligible but not referred (2.17 exacerbations/patient-year; 95% CI, 2.11-2.24)., Conclusions: This study found that < 10% of patients who were eligible for PR were actually referred. Patients who were eligible and referred for (but not necessarily completed) PR did not have fewer GP visits and hospitalizations for AECOPD in the year following PR compared with those not referred or compared with the year prior to PR., (Copyright © 2017 American College of Chest Physicians. Published by Elsevier Inc. All rights reserved.)

Background: Acute exacerbation of COPD (AECOPD) has a significant impact on health-care use, including physician visits and hospitalizations. Previous studies and reviews have shown that pulmonary rehabilitation (PR) has many benefits, but the effect on hospitalizations for AECOPD is inconclusive., Methods: A literature search was carried out to find studies that might help determine, using a meta-analysis, the impact of PR on AECOPD, defined as unscheduled or emergency hospitalizations and ED visits. Cohort studies and randomized controlled trials (RCTs) reporting hospitalizations for AECOPD as an outcome were included. Meta-analyses compared hospitalization rates between eligible PR recipients and nonrecipients before and after rehabilitation., Results: Eighteen studies were included in the meta-analysis. Results from 10 RCTs showed that the control groups had a higher overall rate of hospitalization than did the PR groups (control groups: 0.97 hospitalizations/patient-year; 95% CI, 0.67-1.40; PR groups: 0.62 hospitalizations/patient-year; 95% CI, 0.33-1.16). Five studies compared admission numbers in the 12 months before and after rehabilitation, finding a significantly higher admission rate before compared with after (before: 1.24 hospitalizations/patient-year; 95% CI, 0.66-2.34; after: 0.47 hospitalizations/patient-year; 95% CI, 0.28-0.79). The pooled result of three cohort studies found that the reference group had a lower admission rate compared with the PR group (0.18 hospitalizations/patient-year; 95% CI, 0.11-0.32 for reference group vs 0.28 hospitalizations/patient-year; 95% CI, 0.25-0.32 for the PR group)., Conclusions: Although results from RCTs suggested that PR reduces subsequent admissions, pooled results from the cohort studies did not, likely reflecting the heterogeneous nature of individuals included in observational research and the varying standard of PR programs., (Copyright © 2016 American College of Chest Physicians. Published by Elsevier Inc. All rights reserved.)

Objective: Family studies and twin studies demonstrate that lower urinary tract symptoms and pelvic organ prolapse are heritable. This review aimed to identify genetic polymorphisms tested for an association with lower urinary tract symptoms or prolapse, and to assess the strength, consistency, and risk of bias among reported associations., Study Design: PubMed and HuGE Navigator were searched up to May 1, 2014, using a combination of genetic and phenotype key words, including "nocturia," "incontinence," "overactive bladder," "prolapse," and "enuresis." Major genetics, urology, and gynecology conference abstracts were searched from 2005 through 2013. We screened 889 abstracts, and retrieved 78 full texts. In all, 27 published and 7 unpublished studies provided data on polymorphisms in or near 32 different genes. Fixed and random effects metaanalyses were conducted using codominant models of inheritance. We assessed the credibility of pooled associations using the interim Venice criteria., Results: In pooled analysis, the rs4994 polymorphism of the ADRB3 gene was associated with overactive bladder (odds ratio [OR], 2.5; 95% confidence interval [CI], 1.7-3.6; n = 419). The rs1800012 polymorphism of the COL1A1 gene was associated with prolapse (OR, 1.3; 95% CI, 1.0-1.7; n = 838) and stress urinary incontinence (OR, 2.1; 95% CI, 1.4-3.2; n = 190). Other metaanalyses, including those for polymorphisms of COL3A1,LAMC1,MMP1,MMP3, and MMP9 did not show significant effects. Many studies were at high risk of bias from genotyping error or population stratification., Conclusion: These metaanalyses provide moderate epidemiological credibility for associations of variation in ADRB3 with overactive bladder, and variation of COL1A1 with prolapse. Clinical testing for any of these polymorphisms cannot be recommended based on current evidence., (Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.)

We have developed a reporter protein system for the experimental verification of twin-arginine signal peptides. This reporter system is based on the Streptomyces coelicolor agarase protein, which is secreted into the growth medium by the twin-arginine translocation (Tat) pathway and whose extracellular activity can be assayed colorimetrically in a semiquantitative manner. Replacement of the native agarase signal peptide with previously characterized twin-arginine signal peptides from other Gram-positive and Gram-negative bacteria resulted in efficient Tat-dependent export of agarase. Candidate twin-arginine signal peptides from archaeal proteins as well as plant thylakoid-targeting sequences were also demonstrated to mediate agarase translocation. A naturally occurring variant signal peptide with an arginine-glutamine motif instead of the consensus di-arginine was additionally recognized as a Tat-targeting sequence by Streptomyces. Application of the agarase assay to previously uncharacterized candidate Tat signal peptides from Bacillus subtilis identified two further probable Tat substrates in this organism. This is the first versatile reporter system for Tat signal peptide identification.

Objective: To describe a collaborative interdisciplinary health care service delivery system for the medically indigent in the Tulsa and northeastern Oklahoma area independent of state or federal funding., Setting: Northeastern Oklahoma and Tulsa., Practice Description: Community and ambulatory care for indigent patients., Practice Innovation: Bedlam Community Health Clinic (BCHC), which opened in August 2003, provides services to patients through partnerships among the health care disciplines of the University of Oklahoma College of Pharmacy, Nursing, and Medicine; is staffed by community physicians and pharmacists who volunteer their time and expertise; and is funded by the local community., Main Outcome Measures: Experiences and patients served., Results: BCHC is a collaborative interdisciplinary clinic that addresses the needs of the medically indigent in Tulsa and northeastern Oklahoma. Conceived, developed, and funded by the local community, it does not depend on state or federal funding. A variety of services, both general medicine and specialty, are provided through BCHC. Since its opening in August 2003, the clinic has provided hands-on training for students from a variety of health care disciplines. The pharmacist-patient encounters provide helpful, meaningful drug information. The participation of volunteer pharmacists enables medically underserved or indigent patients to access pharmaceutical care and addresses the diverse health care needs of this often overlooked population., Conclusion: Health professionals and students in the Tulsa area have created an innovative mechanism for serving indigent patients who otherwise would lack adequate health care services.

All secreted proteins in Escherichia coli must be maintained in an export-competent state before translocation across the inner membrane. In the case of the Sec pathway, this function is carried out by the dedicated SecB chaperone and the general chaperones DnaK-DnaJ-GrpE and GroEL-GroES, whose job collectively is to render substrate proteins partially or entirely unfolded before engagement of the translocon. To determine whether these or other general molecular chaperones are similarly involved in the translocation of folded proteins through the twin-arginine translocation (Tat) system, we screened a collection of E. coli mutant strains for their ability to transport a green fluorescent protein (GFP) reporter through the Tat pathway. We found that the molecular chaperone DnaK was essential for cytoplasmic stability of GFP bearing an N-terminal Tat signal peptide, as well as for numerous other recombinantly expressed endogenous and heterologous Tat substrates. Interestingly, the stability conferred by DnaK did not require a fully functional Tat signal as substrates bearing translocation defective twin lysine substitutions in the consensus Tat motif were equally unstable in the absence of DnaK. These findings were corroborated by crosslinking experiments that revealed an in vivo association between DnaK and a truncated version of the Tat substrate trimethylamine N-oxide reductase (TorA502) bearing an RR or a KK signal peptide. Since TorA502 lacks nine molybdo-cofactor ligands essential for cofactor attachment, the involvement of DnaK is apparently independent of cofactor acquisition. Finally, we show that the stabilizing effects of DnaK can be exploited to increase the expression and translocation of Tat substrates under conditions where the substrate production level exceeds the capacity of the Tat translocase. This latter observation is expected to have important consequences for the use of the Tat system in biotechnology applications where high levels of periplasmic expression are desirable.

Recombinant human thrombin (rhThrombin) is being developed as an alternative to thrombin products purified from pooled human or bovine plasma, which are currently marketed for topical hemostasis. Preclinical studies of rhThrombin were conducted prior to its evaluation as a topical adjunct to surgical hemostasis in clinical trials. No overt clinical pathology or signs were observed in cynomolgus monkeys following implantation of a gelatin sponge containing either rhThrombin or bovine thrombin to a surgical liver wound, and similar gross and microscopic wound healing characteristics were observed over an eight-week recovery period with either compound. Repeated subcutaneous injections of rhThrombin or bovine thrombin to cynomolgus monkeys produced no treatment-related effects. Whereas no monkeys demonstrated anti-rhThrombin antibody seroconversion, specific anti-bovine antibodies were detected in all tested monkeys exposed to bovine thrombin. Addition of rhThrombin or bovine thrombin to mouse fibroblast cells resulted in expected detachment and shape change. Topical application of rhThrombin to rabbits did not cause irritation to the eye, normal skin, or abraded skin. These studies showed that topical, subcutaneous, or implanted rhThrombin was minimally immunogenic, safe, and well tolerated in nonclinical models, and supported the clinical evaluation of rhThrombin in a variety of surgical settings.

There is increasing evidence that hippocampal learning correlates strongly with neurogenesis in the adult brain. Increases in neurogenesis after brain injury also correlate with improved outcomes. With aging the capacity to generate new neurons decreases dramatically, both under normal conditions and after injury. How this decrease occurs is not fully understood, but we hypothesized that transforming growth factor (TGF)-beta1, a cell cycle regulator that rapidly increases after injury and with age, might play a role. We found that chronic overproduction of TGF-beta1 from astrocytes almost completely blocked the generation of new neurons in aged transgenic mice. Even young adult TGF-beta1 mice had 60% fewer immature, doublecortin-positive, hippocampal neurons than wild-type littermate controls. Bromodeoxyuridine labeling of dividing cells in 2-month-old TGF-beta1 mice confirmed this decrease in neuro-genesis and revealed a similar decrease in astrogenesis. Treatment of early neural progenitor cells with TGF-beta1 inhibited their proliferation. This strongly suggests that TGF-beta1 directly affects these cells before their differentiation into neurons and astrocytes. Together, these data show that TGF-beta1 is a potent inhibitor of hippocampal neural progenitor cell proliferation in adult mice and suggest that it plays a key role in limiting injury and age-related neurogenesis.

The Tat system functions to transport folded proteins across the bacterial cytoplasmic membrane and the thylakoid membrane of plant chloroplasts. Tat transport involves a high molecular weight TatBC-containing complex that transiently associates with TatA during protein translocation. Sedimentation equilibrium experiments were used to determine a protein-only molecular mass for the TatBC complex of 630+/-30kDa, suggesting that it contains approximately 13 copies of the TatB and TatC protomers. Point mutations that inactivate Tat transport have previously been identified in each of TatA, TatB, and TatC. Analysis of the TatBC complexes formed by these inactive variants demonstrates that the amino acid substitutions neither affect the composition of the TatBC complex nor cause accumulation of the assembled TatABC translocation site. In addition, the TatA protein is shown not to be required for the assembly or stability of the TatBC complex.

Objectives: To determine whether community pharmacists using a risk assessment tool could encourage men who were overdue for a physical examination to visit a physician and to calculate the return on investment from the pharmacy perspective for offering a complimentary risk assessment service., Design: 12-week, prospective cohort study using convenience sampling among men who visited participating pharmacies., Setting: Cross-section of community pharmacies., Patients: 382 men aged 25-74 years with potential health risks that were untreated or uncontrolled, or who had not had a physical examination within the past year., Intervention: Screening for specific health risks with or without telephone follow-up., Main Outcome Measure: Overall male patient response to pharmacist recommendations for follow-up medical care., Results: Of 382 men identified by the Men's Health Risk Assessment Tool (MHRAT) as being at risk for 1,194 significant health conditions (mean, 3.1 conditions per patient), 69% had not received a physical examination from a physician for a period ranging from more than 1 year to 22.6 years. Of men who were recommended to make an appointment, 64% were seen by a physician or were waiting on a scheduled appointment at the end of the study. No differences were seen between the telephone intervention group and the control group in rates of obtaining a physician examination., Conclusion: A positive public health initiative involving community pharmacists was demonstrated in this study. Community pharmacists had a significant impact on motivating men to see a physician for follow-up care once a potential health risk was identified. The MHRAT and the pharmacist recommendation or patient education were the motivating factors and not follow-up telephone interventions by the pharmacist. Given community pharmacists' unique accessibility, an enormous opportunity exists for community pharmacists to raise awareness of men's health care and influence men's health behavior.

The Escherichia coli Tat apparatus is a protein translocation system that serves to export folded proteins across the inner membrane. The integral membrane proteins TatA, TatB and TatC are essential components of this pathway. Substrate proteins are directed to the Tat apparatus by specialized N-terminal signal peptides bearing a consensus twin-arginine sequence motif. Here we have systematically examined the Tat complexes that can be purified from overproducing strains. Our data suggest that the TatA, TatB and TatC proteins are found in at least two major types of high molecular mass complex in detergent solution, one consisting predominantly of TatA but with a small quantity of TatB, and the other based on a TatBC unit but also containing some TatA protein. The latter complex is shown to be capable of binding a Tat signal peptide. Using an alternative purification strategy we show that it is possible to isolate a TatABC complex containing a high molar excess of the TatA component.

The bacterial Tat pathway is capable of exporting folded proteins carrying a special twin arginine (RR) signal peptide. By using two in vivo reporter proteins, we assessed factors that affect Tat pathway transport. We observed that, like the intact RR signal peptide, those with a KR or RK substitution were still capable of mediating the translocation of the folded green fluorescent protein (GFP). However, the translocation efficiency decreased in the order of RR>KR>RK. The KK motif was unable to mediate GFP translocation. The translocation of the RR-GFP fusion required TatA, TatB and TatC proteins. By exploiting the periplasmic bactericidal property of colicin V (ColV), we constructed a translocation-suicide probe, RR-ColV. The translocation of RR-ColV fully inhibited the growth of wild-type Escherichia coli and those of the DeltatatD and DeltatatE mutants. In contrast, the deletion of the tatC gene blocked RR-ColV in the cytoplasm and this strain exhibited a normal growth phenotype. Interestingly, the growth of DeltatatA and tatB mutants was inhibited partially by RR-ColV. Moreover, KR, RK and KK motifs were capable of mediating the ColV translocation with a decreasing RR=KR>RK>KK efficiency. In addition to TatE and TatC proteins, either TatA or TatB was sufficient for the translocation of RR-ColV or KR-ColV. In contrast, TatA plus the conserved N-terminal domain of TatB were required to mediate the killing effect of ColV fused to the less-efficient RK signal peptide. Taken together, these results suggest that a fully efficient Tat pathway transport is determined by the sequence of the signal peptide, the composition of the Tat apparatus, and the intrinsic characteristics of exported proteins., (Copyright 2002 Elsevier Science Ltd.)

A method is presented for the preparation and assay of lactate dehydrogenase isoenzymes 1 and 2 as pure fractions. The total method involves the use of heat treatment to destroy the heat-labile fractions (isoenzymes 3, 4 and 5); fractionation using an ion-exchange resin; and immunochemical blocking of the muscle subunit, to remove any contamination of the fraction containing isoenzyme 1 with isoenzyme 2 and vice versa. Finally, the enzyme activities in the various fractions are measured using a standard kinetic assay procedure. Estimates can be obtained of all five isoenzymes if the heat treatment step is omitted.

Increased plasma and urine levels of pyroglutamic acid were found in 4 patients being fed the low-lactose food Nutramigen. Pyroglutamic acid was detected and estimated by a variety of methods, and the merits of the techniques used and their application in a screening programme are discussed.

A complete absence of plasma carnosinase activity was observed in a series of patients with proven urea cycle defects. This finding could not be explained by age of patients, low protein intake, or inhibition of the enzyme by glutamine or carbamyl phosphate.

Ornithine aminotransferase was purified by conventional biochemical methods from rat kidney, rat liver, and human liver. Affinity-purified antibodies raised to the rat kidney enzyme were used to produce an immunoadsorbent enabling a one-step purification of ornithine aminotransferase to be made from crude human liver extracts. The harsh chemical conditions often required to desorb immunoadsorbents were avoided by isolating antibodies with low functional affinity and employing an electrophoretic desorption method which allowed the enzyme activity to be retained. The close structural similarity between human and rat ornithine aminotransferase was demonstrated by immunodiffusion reactions. It was therefore possible to purify the enzyme from human liver using immobilized antibodies raised against rat kidney ornithine aminotransferase. Furthermore, desorption was more readily achieved due to the lower affinity for the human enzyme.

Increased urinary levels of N-carbamoyl-beta-alanine, and also, on occasions, of N-carbamoylaspartate, were observed in patients with ornithine carbamoyl-transferase (EC 2.1.3.3) deficiency, argininosuccinate synthetase (EC 6.3.4.5) deficiency and argininosuccinate lyase (EC 4.3.2.1)deficiency, but not in a patient with carbamoylphosphate synthase deficiency. The relevance of these findings to the diagnosis of urea cycle defects is discussed.