Bempedoic Acid and Cardiovascular Outcomes in Statin-Intolerant Patients

BACKGROUND

Bempedoic acid, an ATP citrate lyase inhibitor, reduces low-density lipoprotein (LDL) cholesterol levels and is associated with a low incidence of muscle-related adverse events; its effects on cardiovascular outcomes remain uncertain.

METHODS

We conducted a double-blind, randomized, placebo-controlled trial involving patients who were unable or unwilling to take statins owing to unacceptable adverse effects ("statin-intolerant" patients) and had, or were at high risk for, cardiovascular disease. The patients were assigned to receive oral bempedoic acid, 180 mg daily, or placebo. The primary end point was a four-component composite of major adverse cardiovascular events, defined as death from cardiovascular causes, nonfatal myocardial infarction, nonfatal stroke, or coronary revascularization.

RESULTS

A total of 13,970 patients underwent randomization; 6992 were assigned to the bempedoic acid group and 6978 to the placebo group. The median duration of follow-up was 40.6 months. The mean LDL cholesterol level at baseline was 139.0 mg per deciliter in both groups, and after 6 months, the reduction in the level was greater with bempedoic acid than with placebo by 29.2 mg per deciliter; the observed difference in the percent reductions was 21.1 percentage points in favor of bempedoic acid. The incidence of a primary end-point event was significantly lower with bempedoic acid than with placebo (819 patients [11.7%] vs. 927 [13.3%]; hazard ratio, 0.87; 95% confidence interval [CI], 0.79 to 0.96; P = 0.004), as were the incidences of a composite of death from cardiovascular causes, nonfatal stroke, or nonfatal myocardial infarction (575 [8.2%] vs. 663 [9.5%]; hazard ratio, 0.85; 95% CI, 0.76 to 0.96; P = 0.006); fatal or nonfatal myocardial infarction (261 [3.7%] vs. 334 [4.8%]; hazard ratio, 0.77; 95% CI, 0.66 to 0.91; P = 0.002); and coronary revascularization (435 [6.2%] vs. 529 [7.6%]; hazard ratio, 0.81; 95% CI, 0.72 to 0.92; P = 0.001). Bempedoic acid had no significant effects on fatal or nonfatal stroke, death from cardiovascular causes, and death from any cause. The incidences of gout and cholelithiasis were higher with bempedoic acid than with placebo (3.1% vs. 2.1% and 2.2% vs. 1.2%, respectively), as were the incidences of small increases in serum creatinine, uric acid, and hepatic-enzyme levels.

CONCLUSIONS

Among statin-intolerant patients, treatment with bempedoic acid was associated with a lower risk of major adverse cardiovascular events (death from cardiovascular causes, nonfatal myocardial infarction, nonfatal stroke, or coronary revascularization). (Funded by Esperion Therapeutics; CLEAR Outcomes ClinicalTrials.gov number, NCT02993406.).

992 RESULTS OF A PILOT HIV/FRAILTY CLINIC - CAN COMPREHENSIVE GERIATRIC ASSESSMENT BENEFIT FRAIL PEOPLE LIVING WITH HIV?

Introduction

Frailty has been recognised among people living with human immunodeficiency virus (HIV) and will become more prevalent in coming years given treatment success (Pathai et al J Gerontol A Biol Sci Med Sci 2014;69:833–842). Assessment of frailty and its common syndromes through comprehensive geriatric assessment (CGA) is routinely delivered by geriatricians and is likely to benefit these patients. We piloted a clinic to assess whether a future service would be beneficial for people living with HIV and frailty.

Method

10 patients from the local HIV service, with suspected frailty, were referred to the Frailty Unit for assessment in May 2021. Each patient was assessed for frailty using the Fried model. They underwent CGA which included medication review, therapy assessment, cognitive assessment, using the Montreal Cognitive Assessment (MOCA), and review by a geriatrician.

Results

Seven people attended. Six underwent full assessment and one left prior to undergoing medical review. Patient demographics: all white males; mean age 53 years; mean years since HIV diagnosis 11.3; mean Nadir CD4 count 220.4; four with undetectable viral load and three low level viraemia. Four were classified as frail and three pre-frail. All were multimorbid (mean no. co-morbidities, 7.1). Significant medical issues were identified in four patients requiring further investigation and/or referral to other specialities. Polypharmacy was prevalent (mean no. medications 11.1) and medication adjustments were suggested for all patients. The mean MOCA score was 25.7, with two scoring less than 26 prompting memory service referral. Five patients had ongoing physiotherapy/occupational therapy needs.

Conclusion

This pilot demonstrated that a CGA approach to frail patients living with HIV identified significant multimorbidity, polypharmacy, cognitive impairment and therapy needs. This allowed for recommendations to be made to improve medical care, optimise function and improve quality of life. Consequently, a permanent HIV/Frailty service and referral pathway have been developed.

A-13 Demographic Differences in Performance Validity Test Failures

Objective

The present study aimed to investigate demographic differences in performance validity test (PVT) failure in a Veteran sample.

Method

Data were extracted retrospectively from neuropsychological evaluations at a southeastern Veterans Affairs (VA) Medical Center. Only male Veterans who were either European American/White (EA) or African American/Black (AA), and for whom complete data were available were included in the study (N = 1271). We investigated whether performance on two frequently used PVTs, the Test of Memory Malingering (TOMM) and the Medical Symptom Validity Test (MSVT), significantly differed by age, education, race, and VA service connection using separate logistic regressions.

Results

Veterans with younger age, less education, and VA service-connected disability were significantly more likely to fail both PVTs. Race was not a significant predictor of MSVT failure, but AA patients were significantly more likely than EA patients to fail the TOMM. For all significant demographic predictors in the models, effects were small. In a subsample of patients who were given both PVTs (n = 467), the pattern of differences based on race remained; 46% of AA patients and 36% of EA patients failed the TOMM, while 44% of AA patients and 43% of EA patients failed the MSVT.

Conclusions

Performance on the TOMM and MSVT systematically differed based on demographics. Results were not consistent across PVTs, with performance on the TOMM differing between EA and AA patients, but performance on the MSVT did not differ by race. These results suggest that demographic factors may play a small but measurable role in performance on specific PVTs.

Identical and Nonidentical Twins: Risk and Factors Involved in Development of Islet Autoimmunity and Type 1 Diabetes

OBJECTIVE

There are variable reports of risk of concordance for progression to islet autoantibodies and type 1 diabetes in identical twins after one twin is diagnosed. We examined development of positive autoantibodies and type 1 diabetes and the effects of genetic factors and common environment on autoantibody positivity in identical twins, nonidentical twins, and full siblings.

RESEARCH DESIGN AND METHODS

Subjects from the TrialNet Pathway to Prevention Study (N = 48,026) were screened from 2004 to 2015 for islet autoantibodies (GAD antibody [GADA], insulinoma-associated antigen 2 [IA-2A], and autoantibodies against insulin [IAA]). Of these subjects, 17,226 (157 identical twins, 283 nonidentical twins, and 16,786 full siblings) were followed for autoantibody positivity or type 1 diabetes for a median of 2.1 years.

RESULTS

At screening, identical twins were more likely to have positive GADA, IA-2A, and IAA than nonidentical twins or full siblings (all P < 0.0001). Younger age, male sex, and genetic factors were significant factors for expression of IA-2A, IAA, one or more positive autoantibodies, and two or more positive autoantibodies (all P ≤ 0.03). Initially autoantibody-positive identical twins had a 69% risk of diabetes by 3 years compared with 1.5% for initially autoantibody-negative identical twins. In nonidentical twins, type 1 diabetes risk by 3 years was 72% for initially multiple autoantibody-positive, 13% for single autoantibody-positive, and 0% for initially autoantibody-negative nonidentical twins. Full siblings had a 3-year type 1 diabetes risk of 47% for multiple autoantibody-positive, 12% for single autoantibody-positive, and 0.5% for initially autoantibody-negative subjects.

CONCLUSIONS

Risk of type 1 diabetes at 3 years is high for initially multiple and single autoantibody-positive identical twins and multiple autoantibody-positive nonidentical twins. Genetic predisposition, age, and male sex are significant risk factors for development of positive autoantibodies in twins.

Serum NGAL can act as an early renal safety biomarker during long-term nucleos(t)ide analogue antiviral therapy in chronic hepatitis B

Tubular renal toxicity is a side-effect of long-term therapy with nucleos(t)ide analogue(s) (NA) in chronic hepatitis B (CHB). There are no established surrogate markers in plasma of early NA-related toxicity. Neutrophil gelatinase-associated lipocalin (NGAL) is a protein produced by tubular cells following renal damage. We aimed therefore to retrospectively compare conventional renal markers (estimated glomerular filtration rates (eGFR) and urinary protein/creatinine ratio uPCR) with a sensitive biomarker (NGAL) in CHB patients on long-term NA therapy and assess the ability of new markers to predict NA-related renal toxicity (new onset of nonalbumin proteinuria). A total of 192 naïve CHB patients (median age 41 years, 78% males, 25% HBeAg+, 35% cirrhosis) were NA treated for at least 5 years (median 8.34 years, range 5.54-11.1 years). The eGFR and uPCR were compared at baseline and last clinical visit with serum NGAL concentrations measured by ELISA at same time-points and assessed according to the presence/absence of nonalbumin proteinuria at last visit. While baseline and last visit eGFR were similar (median:78 vs 84 mL/min), serum NGAL concentrations increased during therapy (median:9.4 vs 16.4 ng/mL, P < .05). The proportion of patients with proteinuria (uPCR > 15) increased between baseline and last visit (4.6% vs 21.4%, P < .05), with 30 (16%) patients having de novo nonalbumin proteinuria at last visit. High baseline NGAL concentrations were exclusive to patients with de novo nonalbumin proteinuria (median:31.7 vs 7.8 ng/mL, P < .01) and baseline NGAL levels >25 mg/mL were predictive of nonalbumin proteinuria at last visit (AUROC = 0.813). In conclusion, serum NGAL can act as a surrogate marker of early renal injury (de novo nonalbumin proteinuria) in CHB on long-term NA therapy.

HBsAg plasma level kinetics: a new role for an old marker as a therapy response predictor in vertically infected children on combination therapy

We aimed to investigate the ability of HBsAg plasma level kinetics to predict therapy response by studying 23 children with infancy-acquired chronic hepatitis B (CHB) during combination sequential therapy with lead-in lamivudine (LAM) and add-on interferon-α (IFN-α) [5 responders (R = anti-HBs seroconversion) and 18 nonresponders (NR)] and to assess their relationship with pretreatment intrahepatic HBV-DNA and cccDNA and HBsAg and HBcAg liver expression. Plasma HBsAg levels were measured in samples before (treatment week 0 = TW0), during (TW9, TW28, TW52) and after (follow-up week = FUW24) therapy by Abbott ARCHITECT(®) assay [log10 IU/mL]. Baseline liver HBV-DNA and cccDNA were quantified by real-time TaqMan PCR [log10 copies/ng genomic DNA]. HBsAg and HBcAg liver expression was evaluated by immunostaining of formalin-fixed, paraffin-embedded specimens [number of positive cells/1000 hepatocytes]. All results are presented as medians. Plasma: at baseline, on-treatment and during follow-up, HBsAg levels were lower in R than NR (TW0: 4.36 vs 4.75;TW28: 2.44 vs 4.35;TW52: 0 vs 4.08 and FUW24: 0.17 vs 4.35, all P < 0.05). Liver: baseline HBV-DNA (3.82 vs 4.71, P = 0.16) and cccDNA (1.98 vs 2.26, P = 0.18) tended to be lower in R than NR, HBsAg expression was lower in R than NR (0.5 vs 4.7, P = 0.03), and HBcAg expression was similar between R and NR. There were positive correlations between plasma HBsAg levels and liver HBV-DNA (r = 0.44, P = 0.04), cccDNA (r = 0.41, P = 0.04) and HBsAg liver expression (r = 0.38, P = 0.05). Lower baseline HBsAg plasma levels, lower HBsAg expression in liver and on-treatment decline of plasma HBsAg levels heralds HBsAg clearance and response to treatment in tolerant children with CHB.

Identification and complete genome analysis of a virus variant or putative new foveavirus associated with apple green crinkle disease

A virus identified as "apple green crinkle associated virus" (AGCaV) was isolated from Aurora Golden Gala apple showing severe symptoms of green crinkle disease. Evidence was obtained of a potential causal relationship to the disease. The viral genome consists of 9266 nucleotides, excluding the poly(A) tail at the 3'-terminus. It has a genome organization similar to that of members of the species Apple stem pitting virus (ASPV), the type species of the genus Foveavirus, family Betaflexiviridae. ORF1 of AGCaV encodes a replicase-complex polyprotein with a molecular mass of 247 kDa; the proteins of ORFs 2, 3, and 4 (TGB proteins) are estimated to be 25.1 kDa, 12.8 kDa, and 7.4 kDa, respectively; and ORF5 encodes the CP, with an estimated molecular mass of 43.3 kDa. Interestingly, AGCaV utilizes different stop codons for ORF1, ORF3, and ORF5 compared to the ASPV type isolate PA66, and between the two viruses, six distinct indel events were observed within ORF5. AGCaV has four non-coding regions (NCRs), including a 5'-NCR (60 nt), a 3'-NCR (134 nt), and two intergenic (IG) NCRs: IG-NCR1 (69 nt) and IG-NCR2 (91 nt). A conserved stable hairpin structure was identified in the variable 5'-NCR of members of the genus Foveavirus. AGCaV may be a variant or strain of ASPV with unique biological properties, but there is evidence that it may be a distinct putative foveavirus.

Reactivation of latent hepatitis B virus infection with HIV-related immunosuppression

The effect of HIV-related immunosuppression and antiretroviral therapy on the reactivation of latent hepatitis B virus (HBV) infection is unclear. We report four patients with advanced HIV-related immunosuppression and abnormal liver function tests who had evidence of HBV reactivation. Reclearance of hepatitis B occurred in two cases with HIV treatment regimens not containing lamivudine, suggesting that improved immune function may be responsible. In three cases, HBV reactivation was recognized during investigation for abnormal liver function initially attributed to drug toxicity. The possibility of HBV reactivation must be considered in the differential diagnosis of abnormal liver function in cases with advanced HIV.

Multiplicity and pseudorapidity distributions of photons in Au+Au collisions at square root of (S(NN)) = 62.4 GeV

We present the first measurement of pseudorapidity distribution of photons in the region 2.3 < or = eta < or = 3.7 for different centralities in Au+Au collisions at square root of (S(NN)) = 62.4 GeV. We find that the photon yield scales with the number of participating nucleons at all collision centralities studied. The pseudorapidity distribution of photons, dominated by pi0 decays, has been compared to those of charged pions, photons, and inclusive charged particles from heavy-ion and nucleon-nucleon collisions at various energies. The photon production has been shown to be consistent with the energy and centrality independent limiting fragmentation scenario.

Ovarian choriocarcinoma in a rhesus monkey associated with elevated serum chorionic gonadotropin levels

A clinically normal, 3-year-old female rhesus monkey (Macaca mulatta), which was part of a routine toxicology study, had a mass in the right ovary with metastases to the adjacent mesentery and lungs. The histologic features and immunohistochemistry results were consistent with the diagnosis of choriocarcinoma. Neoplastic cell types included cytotrophoblast (positive for cytokeratin), syncytiotrophoblast (positive for human chorionic gonadotropin), and extravillous trophoblast (positive for human placental lactogen). Because the neoplasm was present in the ovary, the uterus was normal, and the animal was not currently pregnant, this was considered a primary ovarian neoplasm of germ cell origin. The monkey had elevated serum levels of chorionic gonadotropin at the beginning of the study, indicating that, as in women, choriocarcinomas in monkeys can be associated with increased gonadotropin levels and that the tumor was preexisting at the start of the toxicology study.

Pharmacokinetics and tissue disposition in monkeys of an antisense oligonucleotide inhibitor of Ha-ras encapsulated in stealth liposomes

PURPOSE

This study examined the pharmacokinetics and tissue distribution of an antisense oligonucleotide ISIS 2503, formulated in stealth (pegylated) liposomes (encapsulated) or in phosphate-buffered saline (unencapsulated).

METHODS

Encapsulated or unencapsulated ISIS 2503 was administered to rhesus monkeys by intravenous infusion. The concentrations of ISIS 2503 and metabolites in blood, plasma, and tissue samples were determined by capillary gel electrophoresis.

RESULTS

Plasma concentrations of encapsulated ISIS 2503 decreased mono-exponentially after infusion with a mean half-life of 57.8 hours. In contrast, the concentration of unencapsulated ISIS 2503 in plasma decreased rapidly with a mean half-life of 1.07 hours. Both encapsulated and unencapsulated ISIS 2503 distributed widely into tissues. Encapsulated ISIS 2503 distributed primarily to the reticulo-endothelial system and there were few metabolites observed. In contrast, unencapsulated ISIS 2503 distributed rapidly to tissue with highest concentration seen in kidney and liver. Nuclease-mediated metabolism was extensive for unencapsulated oligonucleotide in plasma and tissues.

CONCLUSIONS

The data suggest that stealth liposomes protect ISIS 2503 from nucleases in blood and tissues, slow tissue uptake, and slow the rate of clearance from the systemic circulation. These attributes may make these formulations attractive for delivering oligonucleotides to sites with increased vasculature permeability such as tumors or sites of inflammation.

Transport in a grooved perfusion flat-bed bioreactor for cell therapy applications

This study considers the transport of oxygen (a growth-associated solute) and lactate (a metabolic byproduct) in a flat-bed perfusion chamber modified to retain cells through the addition of grooves, perpendicular to the direction of flow, at the chamber bottom. The chamber has been successfully applied to hematopoietic cell culture and may be useful for other basic and applied biomedical applications. The objective of this study is to characterize the culture environment in terms of solute transport under various operational conditions. This will allow one to improve the design and operating strategy of the perfusion system for maximizing cell numbers. The system is numerically simulated using the finite element package FIDAP. The reaction kinetics describing oxygen uptake by cells are simplified to zero order to give an upper bound for the oxygen consumption. A flat-bed chamber without grooves is considered here as a benchmark. We show that the growth environment is not oxygen limited (local oxygen concentration above 10 microM) for a variety of flow rates and culture conditions (qO2 = 0.1 micromol/(10(6) cells h)). With a medium flow rate of 2.5 mL/min through the reactor, the model predicts that the 29-cm2 reactor can support at least 33.4 x 10(6) total cells when the inlet medium is in equilibrium with high (20%) oxygen concentration. The culture becomes oxygen limited however for the same flow rate for low (5%) oxygen concentration and can only support 7.2 x 10(6) total cells. Comparison of grooved vs nongrooved chambers reveals that the presence of grooves only affects solute transport on a local scale. This result is attributed to the small size (200 microgram) of the cavities relative to the chamber dimensions. The comparison also yields an empirical relation that allows for rapid estimation of oxygen and lactate concentrations in the grooves using only the numerical simulation of the simpler nongrooved chamber. Finally, our investigation shows that, while decreasing the spacing between cavities decreases the total number of cells the reactor can support, the efficiency of the reactor is increased by 25% (on an area basis) without growth restriction.

Classifying general medicine readmissions. Are they preventable? Veterans Affairs Cooperative Studies in Health Services Group on Primary Care and Hospital Readmissions

OBJECTIVES

To describe a new quality assessment method used to classify the preventability of hospitalization in terms of patient, clinician, or system factors.

DESIGN

The instrument was developed in two phases. Phase 1 was a prospective comparison of admitting residents' and their attending physicians' classifications of the perceived preventability of consecutive admissions to one Veterans Affairs Medical Center (VAMC) excluding admissions to the intensive care unit (ICU). In phase 2, a panel of 10 physicians rated 811 abstracted records of readmissions from nine VAMCs.

SETTING

Nine VAMCs across the United States with varying degrees of university hospital affiliation.

PATIENTS

Phase 1, 156 patients admitted to the general medicine service at the Durham VAMC. Phase 2, 514 patients accounting for 811 readmissions within 6 months of a general medicine service discharge at nine VAMCs.

MEASUREMENTS AND MAIN RESULTS

Physicians used a checklist to record the reason for hospitalization, the preventability of the hospitalization, and, if preventable, a reason defining preventability, which was classified in terms of system, clinician, and patient factors. In phase 2, two physician panelists assessed preventability for each chart. When two panelists disagreed on the preventability of hospitalization, a third panelist, blind to the original assessments, rated the chart. In phase 1, residents and attending physicians rated 33% and 34% of admissions as preventable (kappa = 0.41), respectively. In phase 2, 277 (34%) of 811 readmissions were deemed preventable. Intraobserver accuracy for the assessment of preventability was 96% (kappa = 0.89). interobserver accuracy was 73% (kappa = 0.43). Hospital system factors accounted for 37% of preventable readmissions, clinician factors for 38%, and patient factors for 21%. The nine hospitals differed markedly in their profile of reasons for preventable readmissions (p = .005).

CONCLUSIONS

Using a new method of determining the preventability of hospitalizations, we identified several factors that might avert hospitalizations. Focusing efforts to identify preventable hospitalizations may yield better methods for managing patients' total health care needs; however, the content of those efforts will vary by institution.

Characterization of the 2H12 antigen as a nonshuttling human isoelectric variant of the nucleolar protein B23

It has become obvious that a better understanding of the nucleolar compartment should encompass the elucidation of structural and functional relationships between its molecular constituents. Using a mouse monoclonal antibody referred to as 2H12, we have identified a human epitope that appears to be implicated in the regulatory events governing the elaboration and stabilization of the nucleolar architecture. By immunofluorescence and immunoblotting, the 2H12 monoclonal was shown to be directed against a nucleolar protein with a relative mobility of 38-40 kDa and an isoelectric point of 5.1 that is present in human cells, regardless of their proliferation state. No reactivity was detected in cells from other species, implying that the targeted epitope could be unique to humans. Investigation of the fate of the epitope throughout the cell cycle led to evidence that its immunoreactivity was phosphodependent and suggested that the disassembly and reassembly of the nucleolar apparatus during cell division is accompanied by dephosphorylation/phosphorylation modifications at this site. In a series of double immunofluorescence experiments and two-dimensional immunoblotting analyses, it was demonstrated that the 2H12 antigen corresponds to an isoelectric variant of the human nucleolar protein B23 that is most prominent during interphase. Tightly associated with the nuclear matrix, this human B23 isoelectric variant did not shuttle between the nucleus and the cytoplasm but remained sequestered within the human nucleolus during mobility assays in human-murine heterokaryons.

Community hospitals and the Internet: lessons from pilot connections

Community hospitals in rural and isolated areas have had little access to the Internet. In 1992, the National Library of Medicine funded a pilot project to be conducted by the University of Washington and seven community hospitals in the northwestern United States. The goals of the project were to connect the hospitals to the Internet and study the uses made of this resource. A number of administrative, technical, financial, and organizational problems were dealt with in the attempt to establish the Internet connections and introduce this resource to these health care settings. This paper examines these issues and presents conclusions drawn from the experiences of the project team.

Successful treatment of acute lymphoblastic leukemia in a child with cystic fibrosis

A 3 1/2 year old girl with cystic fibrosis who underwent successful treatment for acute lymphoblastic leukemia remains in complete remission 36 months after diagnosis. We also report high clearance rates of three antineoplastic agents in this patient. Drug doses were adjusted to achieve optimal systemic exposure.

Altered mercaptopurine metabolism, toxic effects, and dosage requirement in a thiopurine methyltransferase-deficient child with acute lymphocytic leukemia

Thiopurine methyltransferase deficiency, inherited as an autosomal codominant trait, is associated with aberrant mercaptopurine metabolism leading to excessive cellular accumulation of 6-thioguanine nucleotides, the active metabolites of mercaptopurine. We describe a case of severe thiopurine methyltransferase deficiency (activity less than 1 U/8 x 10(8) erythrocytes) in a young girl with acute lymphocytic leukemia. The level of 6-thioguanine nucleotide in the patient's erythrocytes was seven times the population median value, and she had intolerable hematologic toxic effects during postremission therapy with a standard dosage of mercaptopurine (75 mg/m2 per day). Subsequent therapy with 6% of this dosage (10 mg/m2 three times weekly) yielded erythrocytic 6-thioguanine nucleotide concentrations consistently above the population median but not associated with prohibitively toxic effects. This case demonstrates that thiopurine methyltransferase deficiency does not absolutely contraindicate mercaptopurine therapy, and it also provides insight into the mechanism of excessive toxic effects of mercaptopurine sometimes observed in children with acute lymphocytic leukemia.

The metabolism of fenclofenac in the horse

14C-Fenclofenac (2-(2'-4'-dichlorophenoxy)-phenylacetic acid) was administered orally to horses, and urinary metabolites investigated by chromatography. Fenclofenac was rapidly absorbed and eliminated, with a plasma half-life (t1/2) of 2.3 h, with 83.2 and 85.8% of the dose being recovered in the urine in 0-24 h. The major urinary metabolite was the ester glucuronide (58.8, 70.0% dose), and evidence is presented that this metabolite undergoes a structural rearrangement to give beta-glucuronidase-resistant isomers. The other 14C-labelled components in horse urine were unchanged fenclofenac (13.1, 11.5% dose), and two minor metabolites, one of which was identified as a monohydroxy fenclofenac. This study is the first to show an ester glucuronide to be the major metabolite of a non-steroidal anti-inflammatory drug in the horse.

The frequency of embryogenic pollen grains is not increased by in vitro anther culture in Nicotiana tabacum L

The numbers of embryogenic (S) grains present in in-situ mature anthers of Nicotiana tabacum L. were compared to the numbers of embryos and plantlets produced in cultured anthers excised at the optimal mitotic stage of development for anther culture. The Feulgen technique of staining embryos caused a considerable loss of grains from cultured anthers but this did not seriously affect the determination of the percentage of embryos present. In no instance did the numbers of embryos produced exceed the maximum number of S grains found, and the distributions of S grain and embryo frequencies in anthers were similar. In rare instances S grains which had undergone the first embryogenic division were observed in situ. The results indicate that all grains capable of embryogenesis are determined during early flower formation and that their number is not increased by in vitro culture.

Metal template reactions. XII. Comparison of some chemical and physical properties of dibenzocorromin metal complexes with those of corrins and otherrelated systems

Methyl and ethyl derivatives of cobalt(III) dibenzocorromin complexes have been prepared and their properties are compared with those of related cobalt alkyls. A comparison of spectroscopic and electrochemical properties of dibenzocorromin complexes with those of corrins and related systems is also presented.