Gαz-independent and -dependent Improvements With EPA Supplementation on the Early Type 1 Diabetes Phenotype of NOD Mice.

Prostaglandin E2 (PGE2) is a key mediator of inflammation and is derived from the omega-6 polyunsaturated fatty acid, arachidonic acid (AA). In the ß-cell, the PGE2 receptor, Prostaglandin EP3 receptor (EP3), is coupled to the unique heterotrimeric G protein alpha subunit, Gɑz to reduce the production of cyclic adenosine monophosphate (cAMP), a key signaling molecule that activates ß-cell function, proliferation, and survival pathways. Nonobese diabetic (NOD) mice are a strong model of type 1 diabetes (T1D), and NOD mice lacking Gɑz are protected from hyperglycemia. Therefore, limiting systemic PGE2 production could potentially improve both the inflammatory and ß-cell dysfunction phenotype of T1D. Here, we sought to evaluate the effect of eicosapentaenoic acid (EPA) feeding, which limits PGE2 production, on the early T1D phenotype of NOD mice in the presence and absence of Gαz. Wild-type and Gαz knockout NOD mice were fed a control or EPA-enriched diet for 12 weeks, beginning at age 4 to 5 weeks. Oral glucose tolerance, splenic T-cell populations, islet cytokine/chemokine gene expression, islet insulitis, measurements of ß-cell mass, and measurements of ß-cell function were quantified. EPA diet feeding and Gɑz loss independently improved different aspects of the early NOD T1D phenotype and coordinated to alter the expression of certain cytokine/chemokine genes and enhance incretin-potentiated insulin secretion. Our results shed critical light on the Gαz-dependent and -independent effects of dietary EPA enrichment and provide a rationale for future research into novel pharmacological and dietary adjuvant therapies for T1D.

Metformin Monotherapy Alters the Human Plasma Lipidome Independent of Clinical Markers of Glycemic Control and Cardiovascular Disease Risk in a Type 2 Diabetes Clinical Cohort.

Type 2 diabetes (T2D) is a rising pandemic worldwide. Diet and lifestyle changes are typically the first intervention for T2D. When this intervention fails, the biguanide metformin is the most common pharmaceutical therapy. Yet its full mechanisms of action remain unknown. In this work, we applied an ultrahigh resolution, mass spectrometry-based platform for untargeted plasma metabolomics to human plasma samples from a case-control observational study of nondiabetic and well-controlled T2D subjects, the latter treated conservatively with metformin or diet and lifestyle changes only. No statistically significant differences existed in baseline demographic parameters, glucose control, or clinical markers of cardiovascular disease risk between the two T2D groups, which we hypothesized would allow the identification of circulating metabolites independently associated with treatment modality. Over 3000 blank-reduced metabolic features were detected, with the majority of annotated features being lipids or lipid-like molecules. Altered abundance of multiple fatty acids and phospholipids were found in T2D subjects treated with diet and lifestyle changes as compared with nondiabetic subjects, changes that were often reversed by metformin. Our findings provide direct evidence that metformin monotherapy alters the human plasma lipidome independent of T2D disease control and support a potential cardioprotective effect of metformin worthy of future study. SIGNIFICANCE STATEMENT: This work provides important new information on the systemic effects of metformin in type 2 diabetic subjects. We observed significant changes in the plasma lipidome with metformin therapy, with metabolite classes previously associated with cardiovascular disease risk significantly reduced as compared to diet and lifestyle changes. While cardiovascular disease risk was not a primary outcome of our study, our results provide a jumping-off point for future work into the cardioprotective effects of metformin, even in well-controlled type 2 diabetes.

Plasma Prostaglandin E2 Metabolite Levels Predict Type 2 Diabetes Status and One-Year Therapeutic Response Independent of Clinical Markers of Inflammation.

Over half of patients with type 2 diabetes (T2D) are unable to achieve blood glucose targets despite therapeutic compliance, significantly increasing their risk of long-term complications. Discovering ways to identify and properly treat these individuals is a critical problem in the field. The arachidonic acid metabolite, prostaglandin E2 (PGE2), has shown great promise as a biomarker of ß-cell dysfunction in T2D. PGE2 synthesis, secretion, and downstream signaling are all upregulated in pancreatic islets isolated from T2D mice and human organ donors. In these islets, preventing ß-cell PGE2 signaling via a prostaglandin EP3 receptor antagonist significantly improves their glucose-stimulated and hormone-potentiated insulin secretion response. In this clinical cohort study, 167 participants, 35 non-diabetic, and 132 with T2D, were recruited from the University of Wisconsin Hospital and Clinics. At enrollment, a standard set of demographic, biometric, and clinical measurements were performed to quantify obesity status and glucose control. C reactive protein was measured to exclude acute inflammation/illness, and white cell count (WBC), erythrocyte sedimentation rate (ESR), and fasting triglycerides were used as markers of systemic inflammation. Finally, a plasma sample for research was used to determine circulating PGE2 metabolite (PGEM) levels. At baseline, PGEM levels were not correlated with WBC and triglycerides, only weakly correlated with ESR, and were the strongest predictor of T2D disease status. One year after enrollment, blood glucose management was assessed by chart review, with a clinically-relevant change in hemoglobin A1c (HbA1c) defined as ≥0.5%. PGEM levels were strongly predictive of therapeutic response, independent of age, obesity, glucose control, and systemic inflammation at enrollment. Our results provide strong support for future research in this area.

Learning in the COVID-19 pandemic and beyond: development and rapid uptake of an online learning platform for vascular surgery.

INTRODUCTION: With the onset of the COVID-19 pandemic, alternative methods of delivering medical education were rapidly required. An online learning platform was developed with the aim of providing high-quality, accessible learning to vascular specialty trainees. We describe the design, delivery and analysis of the first 15 months of the platform. Although originally a regional initiative, we discuss how popularity and feedback led to a rapid expansion of the training programme internationally. METHODS: A fully online educational platform for vascular surgery specialist trainees was developed. The primary aims and ethos of the programme were that it should be easily accessible from any location, convenient, flexible, cooperative and collaborative, social and free financially to access. All learning resources were researched carefully and based on the UK vascular surgery curriculum and 20 seminal papers targeted in the Vascular Specialist Fellow of the Royal College of Surgeons (FRCSVasc) examination. RESULTS: The project demonstrated that it is feasible to design, build and deliver a postgraduate clinical teaching platform with minimal time requirement, resources and cost while creating and maintaining high-quality content. Rapid national and international uptake has proven there is demand - in addition to overwhelmingly positive feedback from educators and learners, this demonstrates that previously perceived barriers to online education can be overcome. At present, 53 educational sessions have been delivered and are available in the online library, and in the past year (8 December 2020 to 8 December 2021) the website has been accessed 3,877 times. CONCLUSIONS: Although the programme has grown and evolved, a strong focus is being kept on its original ethos and aims - easily accessible, collaborative, free learning resources for all vascular professionals, based on the UK vascular surgery curriculum. Making learning convenient is key. The COVID-19 pandemic may be a watershed moment for a new era of learning. It is an opportunity for people from different backgrounds to share experiences and to develop cohesion within a hospital and network, nationally and worldwide.

Human Islet Expression Levels of Prostaglandin E2 Synthetic Enzymes, But Not Prostaglandin EP3 Receptor, Are Positively Correlated with Markers of ß-Cell Function and Mass in Nondiabetic Obesity.

Elevated islet production of prostaglandin E2 (PGE2), an arachidonic acid metabolite, and expression of prostaglandin E2 receptor subtype EP3 (EP3) are well-known contributors to the ß-cell dysfunction of type 2 diabetes (T2D). Yet, many of the same pathophysiological conditions exist in obesity, and little is known about how the PGE2 production and signaling pathway influences nondiabetic ß-cell function. In this work, plasma arachidonic acid and PGE2 metabolite levels were quantified in a cohort of nondiabetic and T2D human subjects to identify their relationship with glycemic control, obesity, and systemic inflammation. In order to link these findings to processes happening at the islet level, cadaveric human islets were subject to gene expression and functional assays. Interleukin-6 (IL-6) and cyclooxygenase-2 (COX-2) mRNA levels, but not those of EP3, positively correlated with donor body mass index (BMI). IL-6 expression also strongly correlated with the expression of COX-2 and other PGE2 synthetic pathway genes. Insulin secretion assays using an EP3-specific antagonist confirmed functionally relevant upregulation of PGE2 production. Yet, islets from obese donors were not dysfunctional, secreting just as much insulin in basal and stimulatory conditions as those from nonobese donors as a percent of content. Islet insulin content, on the other hand, was increased with both donor BMI and islet COX-2 expression, while EP3 expression was unaffected. We conclude that upregulated islet PGE2 production may be part of the ß-cell adaption response to obesity and insulin resistance that only becomes dysfunctional when both ligand and receptor are highly expressed in T2D.

Prostaglandin EP3 receptor signaling is required to prevent insulin hypersecretion and metabolic dysfunction in a non-obese mouse model of insulin resistance.

When homozygous for the LeptinOb mutation (Ob), Black-and-Tan Brachyury (BTBR) mice become morbidly obese and severely insulin resistant, and by 10 wk of age, frankly diabetic. Previous work has shown prostaglandin EP3 receptor (EP3) expression and activity is upregulated in islets from BTBR-Ob mice as compared with lean controls, actively contributing to their ß-cell dysfunction. In this work, we aimed to test the impact of ß-cell-specific EP3 loss on the BTBR-Ob phenotype by crossing Ptger3 floxed mice with the rat insulin promoter (RIP)-CreHerr driver strain. Instead, germline recombination of the floxed allele in the founder mouse-an event whose prevalence we identified as directly associated with underlying insulin resistance of the background strain-generated a full-body knockout. Full-body EP3 loss provided no diabetes protection to BTBR-Ob mice but, unexpectedly, significantly worsened BTBR-lean insulin resistance and glucose tolerance. This in vivo phenotype was not associated with changes in ß-cell fractional area or markers of ß-cell replication ex vivo. Instead, EP3-null BTBR-lean islets had essentially uncontrolled insulin hypersecretion. The selective upregulation of constitutively active EP3 splice variants in islets from young, lean BTBR mice as compared with C57BL/6J, where no phenotype of EP3 loss has been observed, provides a potential explanation for the hypersecretion phenotype. In support of this, high islet EP3 expression in Balb/c females versus Balb/c males was fully consistent with their sexually dimorphic metabolic phenotype after loss of EP3-coupled Gαz protein. Taken together, our findings provide a new dimension to the understanding of EP3 as a critical brake on insulin secretion.NEW & NOTEWORTHY Islet prostaglandin EP3 receptor (EP3) signaling is well known as upregulated in the pathophysiological conditions of type 2 diabetes, contributing to ß-cell dysfunction. Unexpected findings in mouse models of non-obese insulin sensitivity and resistance provide a new dimension to our understanding of EP3 as a key modulator of insulin secretion. A previously unknown relationship between mouse insulin resistance and the penetrance of rat insulin promoter-driven germline floxed allele recombination is critical to consider when creating ß-cell-specific knockouts.

Agonist-independent Gαz activity negatively regulates beta-cell compensation in a diet-induced obesity model of type 2 diabetes.

The inhibitory G protein alpha-subunit (Gαz) is an important modulator of beta-cell function. Full-body Gαz-null mice are protected from hyperglycemia and glucose intolerance after long-term high-fat diet (HFD) feeding. In this study, at a time point in the feeding regimen where WT mice are only mildly glucose intolerant, transcriptomics analyses reveal islets from HFD-fed Gαz KO mice have a dramatically altered gene expression pattern as compared with WT HFD-fed mice, with entire gene pathways not only being more strongly upregulated or downregulated versus control-diet fed groups but actually reversed in direction. Genes involved in the "pancreatic secretion" pathway are the most strongly differentially regulated: a finding that correlates with enhanced islet insulin secretion and decreased glucagon secretion at the study end. The protection of Gαz-null mice from HFD-induced diabetes is beta-cell autonomous, as beta cell-specific Gαz-null mice phenocopy the full-body KOs. The glucose-stimulated and incretin-potentiated insulin secretion response of islets from HFD-fed beta cell-specific Gαz-null mice is significantly improved as compared with islets from HFD-fed WT controls, which, along with no impact of Gαz loss or HFD feeding on beta-cell proliferation or surrogates of beta-cell mass, supports a secretion-specific mechanism. Gαz is coupled to the prostaglandin EP3 receptor in pancreatic beta cells. We confirm the EP3γ splice variant has both constitutive and agonist-sensitive activity to inhibit cAMP production and downstream beta-cell function, with both activities being dependent on the presence of beta-cell Gαz.

Development and application of high-throughput screens for the discovery of compounds that disrupt ErbB4 signaling: Candidate cancer therapeutics.

Whereas recent clinical studies report metastatic melanoma survival rates high as 30-50%, many tumors remain nonresponsive or become resistant to current therapeutic strategies. Analyses of The Cancer Genome Atlas (TCGA) skin cutaneous melanoma (SKCM) data set suggests that a significant fraction of melanomas potentially harbor gain-of-function mutations in the gene that encodes for the ErbB4 receptor tyrosine kinase. In this work, a drug discovery strategy was developed that is based on the observation that the Q43L mutant of the naturally occurring ErbB4 agonist Neuregulin-2beta (NRG2ß) functions as a partial agonist at ErbB4. NRG2ß/Q43L stimulates tyrosine phosphorylation, fails to stimulate ErbB4-dependent cell proliferation, and inhibits agonist-induced ErbB4-dependent cell proliferation. Compounds that exhibit these characteristics likely function as ErbB4 partial agonists, and as such hold promise as therapies for ErbB4-dependent melanomas. Consequently, three highly sensitive and reproducible (Z' > 0.5) screening assays were developed and deployed for the identification of small-molecule ErbB4 partial agonists. Six compounds were identified that stimulate ErbB4 phosphorylation, fail to stimulate ErbB4-dependent cell proliferation, and appear to selectively inhibit ErbB4-dependent cell proliferation. Whereas further characterization is needed to evaluate the full therapeutic potential of these molecules, this drug discovery platform establishes reliable and scalable approaches for the discovery of ErbB4 inhibitors.

Association of Serum Lipid Profile With Coronary Computed Tomographic Angiography-derived Morphologic and Functional Quantitative Plaque Markers.

PURPOSE: Recent advances in image quality of coronary computed tomographic angiography (cCTA) have enabled improved characterization of coronary plaques. Thus, we investigated the association between quantitative morphological plaque markers obtained by cCTA and serum lipid levels in patients with suspected or known coronary artery disease. MATERIALS AND METHODS: We retrospectively analyzed data of 119 statin-naive patients (55±14 y, 66% men) who underwent clinically indicated cCTA between January 2013 and February 2017. Patients were subdivided into a plaque and a no-plaque group. Quantitative and morphologic plaque markers, such as segment involvement score, segment stenosis score, remodeling index, napkin-ring sign, total plaque volume, calcified plaque volume, and noncalcified plaque volume (NCPV) and plaque composition, were analyzed using a semiautomated plaque software prototype. Total cholesterol, low-density lipoprotein (LDL), high-density lipoprotein, low-density lipoprotein/high-density lipoprotein ratio, and triglycerides were determine in both groups. RESULTS: Higher age (61±11 y vs. 52±14 y, P<0.0001) and a higher likelihood of male gender (77% vs. 56%, P<0.0001) were observed in the plaque group. Differences in lipid levels were neither observed for differentiation between plaque presence or absence, nor after subcategorization for plaque composition. LDL serum levels >160 mg/dL correlated with higher NCPV compared with patients with LDL between 100 and 160 mg/dL (112 vs. 27 mm, P=0.037). Other markers were comparable between the different groups. CONCLUSION: Statin-naive patients with known or suspected coronary artery disease did not show differences in lipid levels related to plaque composition by cCTA. Patients with plaques tended to be men and were significantly older. High LDL levels correlated with high NCPV.

Age-Dependent Protection of Insulin Secretion in Diet Induced Obese Mice.

Type 2 diabetes is an age-and-obesity associated disease driven by impairments in glucose homeostasis that ultimately result in defective insulin secretion from pancreatic ß-cells. To deconvolve the effects of age and obesity in an experimental model of prediabetes, we fed young and aged mice either chow or a short-term high-fat/high-sucrose Western diet (WD) and examined how weight, glucose tolerance, and ß-cell function were affected. Although WD induced a similar degree of weight gain in young and aged mice, a high degree of heterogeneity was found exclusively in aged mice. Weight gain in WD-fed aged mice was well-correlated with glucose intolerance, fasting insulin, and in vivo glucose-stimulated insulin secretion, relationships that were not observed in young animals. Although ß-cell mass expansion in the WD-fed aged mice was only three-quarters of that observed in young mice, the islets from aged mice were resistant to the sharp WD-induced decline in ex vivo insulin secretion observed in young mice. Our findings demonstrate that age is associated with the protection of islet function in diet-induced obese mice, and furthermore, that WD challenge exposes variability in the resilience of the insulin secretory pathway in aged mice.

Acute kidney injury in patients with nephrotic syndrome undergoing contrast-enhanced CT for suspected venous thromboembolism: a propensity score-matched retrospective cohort study.

OBJECTIVES: To determine whether intravenous iodinated contrast material administration increases the risk of acute kidney injury (AKI) in patients with nephrotic syndrome undergoing contrast-enhanced CT. METHODS: Patients with nephrotic syndrome undergoing contrast-enhanced CT were retrospectively identified (n = 701). Control group consisted of patients with nephrotic syndrome receiving non-contrast CT (n = 1053). Two different 1:1 propensity score matching models using three or 10 variables were developed for each estimated glomerular filtration (eGFR) subgroup. Incidence of post-CT AKI for the two groups was assessed and compared by standard AKI criteria and Acute Kidney Injury Network (AKIN) criteria. RESULTS: After matching with three variables, the AKI incidence in the contrast-enhanced CT and non-contrast CT groups was 2.7% vs 2.5% (standard AKI criteria) and 4.2% vs. 6.7% (AKIN criteria) (p = 1.00 and 0.05), respectively. After matching with 10 variables, AKI incidences were 3.1% vs. 2.6% (standard AKI criteria) and 4.1% vs. 7.4% (AKIN criteria) (p = 0.72 and 0.03), respectively. AKI incidences of each eGFR subgroup in the contrast-enhanced CT group were not higher than in the non-contrast CT group (lowest p = 0.46). CONCLUSION: Intravenous contrast material administration during CT was not found to be a risk factor for AKI in this large cohort of patients with nephrotic syndrome. KEY POINTS: • AKI incidence of contrast-enhanced CT and non-contrast CT had no difference. • AKI incidences of eGFR subgroup in contrast-enhanced CT were not increased. • Studies without a non-contrast CT control group may overestimate CIN incidence.

Coronary Computed Tomography Angiography-Derived Plaque Quantification in Patients With Acute Coronary Syndrome.

This study investigated the discriminatory value of quantitative atherosclerotic plaque markers derived from coronary computed tomography angiography (cCTA) in patients with first acute coronary syndrome (ACS) compared with patients with stable coronary artery disease (CAD). Forty patients (56.9 ± 9.3 years, 55% men) admitted with their first ACS and Framingham risk score-matched controls with stable CAD were retrospectively analyzed. All patients had undergone cCTA followed by invasive coronary angiography. Total plaque volume, calcified and noncalcified plaque volumes, plaque burden (in %), remodeling index, lesion length, presence of napkin-ring sign, segment involvement score, and segment stenosis score were derived from cCTA and compared between both groups on a per-lesion and per-patient level. Patients with ACS showed a significant higher number of obstructive CAD and higher values for segment stenosis score, segment involvement score, noncalcified plaque volume, lesion length, and remodeling index than the stable angina group (all p <0.05). On a per-lesion level, culprit lesions had significantly higher values for plaque burden, total plaque volume, noncalcified plaque volume, remodeling index, lesion length, and prevalence of napkin-ring sign in comparison to nonculprit lesions (all p <0.05). On receiver-operating characteristics (ROC) analysis, a stepwise model demonstrated incremental discriminatory power for identifying ACS both per-patient (area under the curve 0.92, p <0.0001) as well as per-lesion (area under the curve 0.88, p <0.0001). cCTA-derived culprit plaque markers show discriminatory value both on a per-patient and per-lesion level. A combination of markers added to the Framingham risk score yields the greatest discriminatory ability.

Treatment of pituitary-dependent Cushing's disease with the multireceptor ligand somatostatin analog pasireotide (SOM230): a multicenter, phase II trial.

CONTEXT: There is currently no medical therapy for Cushing's disease that targets the pituitary adenoma. Availability of such a medical therapy would be a valuable therapeutic option for the management of this disorder. OBJECTIVE: Our objective was to evaluate the short-term efficacy of the novel multireceptor ligand somatostatin analog pasireotide in patients with de novo, persistent, or recurrent Cushing's disease. DESIGN: We conducted a phase II, proof-of-concept, open-label, single-arm, 15-d multicenter study. PATIENTS: Thirty-nine patients with either de novo Cushing's disease who were candidates for pituitary surgery or with persistent or recurrent Cushing's disease after surgery without having received prior pituitary irradiation. INTERVENTION: Patients self-administered sc pasireotide 600 microg twice daily for 15 d. MAIN OUTCOME MEASURE: Normalization of urinary free cortisol (UFC) levels after 15 d treatment was the main outcome measure. RESULTS: Of the 29 patients in the primary efficacy analysis, 22 (76%) showed a reduction in UFC levels, of whom five (17%) had normal UFC levels (responders), after 15 d of treatment with pasireotide. Serum cortisol levels and plasma ACTH levels were also reduced. Steady-state plasma concentrations of pasireotide were achieved within 5 d of treatment. Responders appeared to have higher pasireotide exposure than nonresponders. CONCLUSIONS: Pasireotide produced a decrease in UFC levels in 76% of patients with Cushing's disease during the treatment period of 15 d, with direct effects on ACTH release. These results suggest that pasireotide holds promise as an effective medical treatment for this disorder.

Depopulated bovine ureteric xenograft for complex haemodialysis vascular access.

OBJECTIVES: To assess performance of a de-cellularised bovine ureter vascular graft for haemodialysis in patients for whom conventional access was not possible. METHODS: The Syner Graft Vascular Graft Model 100 (SGVG 100) is a bovine ureter modified by a tissue-engineering depopulation technology and uniquely it is not chemically cross-linked. SGVG 100 was implanted in patients with a failed fistula or vascular access grafts. Graft patency was the primary outcome; secondary outcomes included adverse events and associated treatments. RESULTS: 25 SGVG 100 were implanted in 23 patients; mean age was 59+/-14 years. Mean follow-up was 370 days. The mean time to occlusion (19 events) was 215+/-141 days with patency re-established in 14 of 18 surgical interventions. Thirty angioplasties were performed on 14 SGVG 100 for luminal/anastomotic stenosis. Two grafts demonstrated areas of dilation; however, both grafts continue to be usable at last reported follow-up (930 and 602 days) with no further changes in graft size. Primary patency, assisted primary patency, secondary patency, and freedom from infection were 29, 45, 81, and 95% at 1 year, respectively. CONCLUSIONS: This report demonstrates SGVG 100 is a stable vascular access conduit, providing a suitable graft alternative when autologous vein is not available.

Ureteric complications following renal transplantation: an eight years experience.

OBJECTIVES: Ureteric complications (UCs) following renal transplantation (RT) cause significant morbidity and ureteric stents are employed to bridge the vesico-ureteric anastomosis with a view to preventing these complications. The purpose of this study was to examine the incidence of UCs and outcomes following RT in both stented (STG) and non-stented groups (NSTG) of RT patients. METHODS: This is a retrospective study of a cohort of 650 consecutive RTs [STG (N=267; 41%) and NSTG (N=383; 59%)] performed over a period of 8 years, where the data were retrieved from a prospectively maintained computerised database and case-notes. RESULTS: The overall incidence of UCs was 6.5% (42/650), which consisted of ureteric obstruction (UO) in 4.3% (28) and ureteric leak (UL) in 2.2%(14) of patients. The incidence of UO was significantly high in the NSTG compared to the STG (6.3% vs.1.5%; P=0.002). However, the incidence of UL (3.4% vs.1.3%; P=0.1) and post-transplant urinary tract infection (UTI) (44% vs.41%; P=0.57) were not significantly different between the STG and NSTG groups. UO and UL were associated with significantly high incidence of UTI (P=0.001 and 0.01, respectively). All UCs were managed successfully without allograft loss. CONCLUSIONS: Routine stenting of ureteric anastomosis resulted in reduced incidence of UO without concomitant increased risk of UTI.

Comparative metabolism of genistin by human and rat gut microflora: detection and identification of the end-products of metabolism.

1. Biotransformations by gut microflora play a pivotal role in determining the biological activity of isoflavones that occur in soya-based foods predominantly as betaglycosyl conjugates. Microflora prepared from rat caecae and human faeces were used to investigate the metabolic fate of genistein beta-glycosides extracted from soya flour. The end-products of such metabolism were determined by parallel incubations of microflora with [2',3,5',6'-3H] and [4-14C]-labelled genistein. 2. Quantitative analysis by LC-MS/IS indicated very rapid and complete degradation of genistin, which was associated with a transient increase in genistein. Qualitative studies indicated that the malonyl and acetyl glycosides of genistein were also degraded by the microflora. 3. Incubation of caecal and faecal microflora with [3H] and [14C]genistein yielded similar radiolabelled metabolites, which were identified by radio-LC-MS(n) as the intermediates dihydrogenistein and 6'-hydroxy-O-desmethylangolensin and end-product 4-hydroxyphenyl-2-propionic acid. This profile of genistein metabolites indicated selective hydrolysis of 6'-hydroxy-O-desmethylangolensin between carbon atoms 1' and 1 to yield the end-products 4-hydroxyphenyl-2-propionic acid and 1,3,5-trihydroxybenzene. 4. The biological significance of the products of genistein metabolism warrant further investigation since they may play an important role in mediating the beneficial antioxidant health effects associated with the consumption of isoflavones in food.

Plasma exchange for severe attacks of CNS demyelination: predictors of response.

The authors reviewed 59 consecutive patients treated with plasma exchange (PE) for acute, severe attacks of CNS demyelination at Mayo Clinic from January 1984 through June 2000. Most patients had relapsing-remitting MS (n = 22, 37.3%), neuromyelitis optica (NMO) (n = 10, 16.9%), and acute disseminated encephalomyelitis (n = 10, 16.9%). PE was followed by moderate or marked functional improvement in 44.1% of treated patients. Male sex (p = 0.021), preserved reflexes (p = 0.019), and early initiation of treatment (p = 0.009) were associated with moderate or marked improvement. Successfully treated patients improved rapidly following PE, and improvement was sustained.