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The nuclear ribosomal internal transcribed spacer (ITS) sequences of eight Hypericum species were used to design H. perforatum-specific PCR primers by identification of short "microcode" sequences characteristic of the target species. These were tested with three vouchered H. perforatum DNA samples and eight samples from other species within the Hypericum genus. The most efficient primer combination, FO2 and HRI-S, amplified the genomic DNA from all three H. perforatum samples but not from any of the others apart from H. delphicum. The primer pairing was then tested against seven commercially available ornamental varieties of Hypericum; a positive result was obtained only with the H. perforatum sample. Three consumer products retailed as "St. John's wort" herbal remedies were sampled, two of which gave a positive result for H. perforatum. The assay was sensitive enough to detect 0.75 ng H. perforatum present as just 0.1 % of the total DNA. This method has the potential to be replicated in other plant species and presents a novel use for DNA barcoding data.

cycling during compensated hypertrophy in SHR is a decrease in NCX activity in subepicardial cells; this increases SR Ca 2ϩ content and hence Ca 2ϩ transient amplitude, thus helping to maintain the strength of contraction in the face of an increased afterload. cardiac myocytes; epicardium; endocardium; sarcoplasmic reticulum; t tubules; spontaneously hypertensive rats SYSTEMIC HYPERTENSION IS ASSOCIATED with cardiac morbidity and death (7); the increased afterload imposed on the heart by hypertension results in cardiac hypertrophy, which predisposes to heart failure. Such pressure overload leads to concentric hypertrophy, characterized by an increase in cell size and ventricular wall thickness. Remodeling also results in altered excitation-contraction coupling. In the spontaneously hypertensive rat (SHR), a genetic model of hypertension and cardiac hypertrophy (11, 13), this is characterized by maintained or enhanced systolic Ca 2ϩ transient and contraction amplitude and a slowed time course of contraction and relaxation (4,5,20,30).A number of changes in the excitation-contraction coupling pathway have been identified that may account for the altered Ca 2ϩ transient and contraction, including action potential prolongation, increased sarcoplasmic reticulum (SR) Ca 2ϩ content (5), and larger amplitude Ca 2ϩ sparks (30). However, the mechanisms underlying the changes in Ca 2ϩ transient configuration are still not well understood. In many studies, an increase in Na ϩ /Ca 2ϩ exchange (NCX) expression has been reported during compensated hypertrophy, although, paradoxically, function often appears downregulated or unaltered. For example in the mouse, after surgically induced pressure overload, NCX transcript and protein expression increase but caffeine-evoked inward current and Ni 2ϩ -sensitive current decrease (34). Similarly, in another mouse model of compensated hypertrophy, NCX, SR Ca 2ϩ -ATPase (SERCA), and phospholamban protein levels increase, but NCX current is not significantly altered (16); in addition, in the SHR during compensated hypertrophy, expression of phospholamban, SERCA, and ryanodine receptor are unchanged (30). In contrast, in hypertrophied canine myocytes, Ca 2ϩ extrusion via NCX and Ni 2ϩ -sensitive current are increased (31). Thus there appear to be differences that may be due to the model and to the degree of progression of hypertrophy. In addition, the ventricular myocardium displays regional variations in its structural, mechanical, and electrical properties in normal and hypertrophied hearts (6,20,22,23), probably in part as a result of regional differences in wall stress (25). Recent work in the SHR has shown that the amplitude and time course of the action potential, Ca 2ϩ transient, and contraction are altered differentially in subepicardial (Epi) and subendocardial (Endo) myocytes during compensated hypertrophy (20). However, the mechanisms underlying these regional changes in the Ca 2ϩ transient have not been investigated. The present study was designed, therefore, to investigate the...

Background Peripheral and mucosal eosinophilia may be associated with more aggressive disease in inflammatory bowel disease (IBD) patients. Vedolizumab blocks T lymphocytes, eosinophil adhesion, and extravasation in the gastrointestinal tract. It is not known if mucosal eosinophilia is a predictor for the therapeutic efficacy of vedolizumab. Methods This was a retrospective cohort study of IBD patients with ileal or colonic biopsies who were off steroids before starting vedolizumab. Biopsies were rereviewed by pathologists, and mean eosinophil density was quantified. Patient characteristics and steroid-free clinical response 6 months after beginning vedolizumab were determined. Features were compared between nonresponders and responders, and multivariable logistic regression was performed to identify predictors of clinical response. Results Of 251 IBD patients starting vedolizumab therapy, 65 patients (48% Crohn’s disease, 52% ulcerative colitis) met inclusion criteria. All IBD patients not responding to vedolizumab were more likely to have a higher baseline mean eosinophil count (340 ± 156 vs 236 ± 124; P = 0.004), be previously exposed to an anti-TNF (96% vs 56%; P = 0.001), and be male (58% vs 28%; P = 0.02). Mean eosinophil counts were significantly increased in colonic biopsies in UC nonresponders (438 ± 149 vs 299 ± 145; P = 0.01). A similar trend was seen in CD nonresponders. On multivariable analysis, colonic eosinophil density and prior anti-TNF exposure—and the combination of both—were independent predictors of response. Conclusion In ulcerative colitis, colonic eosinophilia and prior anti-TNF exposure were independent predictors of 6-month clinical nonresponse to vedolizumab. Mucosal eosinophil density as a novel biomarker should be explored in larger patient cohorts. Aside from the previous anti-TNF exposure, eosinophil density in the colon of patients with UC is a negative predictor for a steroid-free long-term response to vedolizumab. The degree colonic eosinophilia may be a novel biomarker that should be further explored.

Modulation of the L-type Ca(2+) channel (LTCC) by sorcin was investigated by measuring the L-type Ca(2+) current (I (Ca,L)) in isolated rabbit ventricular myocytes using ruptured patch, single electrode voltage clamp in the absence of extracellular Na(+). Fifty millimolars EGTA (170 nM Ca(2+)) in the pipette solution buffered bulk cytoplasmic [Ca(2+)], but retained rapid Ca(2+)-dependant inactivation of I (Ca,L,). Recombinant sorcin (3 microM) in the pipette significantly slowed time-dependant inactivation (tau (fast): 8.8 +/- 0.9 vs. 15.1 +/- 1.7 ms). Sorcin had no significant effect on I (Ca,L,) after inhibition of the sarcoplasmic reticulum (SR). Using 10 mM 1,2-bis(o-N,N,N',N'-tetraacetic acid (170 nM Ca(2+)), I (Ca,L) inactivation was then determined by a Ca(2+) -independent, voltage-dependant process. Under these conditions, 3 microM sorcin speeded up inactivation. A similar effect was observed by substitution of Ca(2+) with Ba(2+). Down-regulation of endogenous sorcin to 27 +/- 7% using an RNAi adenoviral vector slowed inactivation of I (Ca,L) by approximately 42%. The effects of sorcin on voltage-dependant inactivation were mimicked by a truncated form of the protein containing only the Ca(2+)-binding domain. This data is consistent with two independent actions of sorcin on the LTCC: (1) slowing Ca(2+)-dependant inactivation and (2) stimulating voltage-dependant inactivation. The net effect of sorcin on the time-dependent inactivation of I (Ca,L) was a balance between these two effects. Under normal conditions, sorcin slows I (Ca,L) inactivation because the effects of Ca(2+)-dependant inactivation out-weigh the effects on voltage-dependant inactivation.