Development of a low phenolic acid diet for the management of orofacial granulomatosis.

BACKGROUND: Orofacial granulomatosis (OFG) is a rare disease of unknown cause. A cinnamon- and benzoate-free diet is successful in up to 72% of patients. Phenolic acids are among the chemical constituents restricted in this diet, which avoids some but not all of these structurally similar compounds. The present study aimed to: (i) develop a novel diet low in phenolic acids; (ii) implement this in a small clinical trial; and (iii) assess its nutritional adequacy. METHODS: A literature review identified 10 papers quantifying phenolic acids from which 91 10-mg phenolic acid exchanges were devised. A phenolic acid exclusion diet with precautionary micronutrient supplementation was designed and implemented in 10 patients. Phenolic acids were excluded for 6 weeks and were reintroduced at a rate of one exchange every second day for 6 weeks. Wilcoxon matched pairs tests analysed disease outcomes measured by an oral disease severity scoring tool at weeks 0, 6 and 12. Nutritional adequacy was assessed, excluding micronutrient supplementation, at weeks 0 and 6, and compared intakes with dietary reference values. RESULTS: The diet was nutritionally inadequate for a range of micronutrients. Seven of 10 patients responded. Mean [standard deviation (SD)] severity scores improved from week 0-6 [20.8 (9.39) and 10.1 (5.72); P = 0.009] and were maintained in five patients who completed the reintroduction [6.6 (3.13) and 7.2 (5.54); P = 0.713]. CONCLUSIONS: A low phenolic acid diet with micronutrient supplementation holds promise of a novel dietary treatment for OFG. Further work is required in larger studies to determine long-term outcomes.

Jacaric acid and its octadecatrienoic acid geoisomers induce apoptosis selectively in cancerous human prostate cells: a mechanistic and 3-D structure-activity study.

Plant-derived non-essential fatty acids are important dietary nutrients, and some are purported to have chemopreventive properties against various cancers, including that of the prostate. In this study, we determined the ability of seven dietary C-18 fatty acids to cause cytotoxicity and induce apoptosis in various types of human prostate cancer cells. These fatty acids included jacaric and punicic acid found in jacaranda and pomegranate seed oil, respectively, three octadecatrienoic geometric isomers (alpha- and beta-calendic and catalpic acid) and two mono-unsaturated C-18 fatty acids (trans- and cis-vaccenic acid). Jacaric acid and four of its octadecatrienoic geoisomers selectively induced apoptosis in hormone-dependent (LNCaP) and -independent (PC-3) human prostate cancer cells, whilst not affecting the viability of normal human prostate epithelial cells (RWPE-1). Jacaric acid induced concentration- and time-depedent LNCaP cell death through activation of intrinsic and extrinsic apoptotic pathways resulting in cleavage of PARP-1, modulation of pro- and antiapoptotic Bcl-2 family of proteins and increased cleavage of caspase-3, -8 and -9. Moreover, activation of a cell death-inducing signalling cascade involving death receptor 5 was observed. Jacaric acid induced apoptosis in PC-3 cells by activation of the intrinsic pathway only. The spatial conformation cis, trans, cis of jacaric and punicic acid was shown to play a key role in the increased potency and efficacy of these two fatty acids in comparison to the five other C-18 fatty acids tested. Three-dimensional conformational analysis using the PubChem Database (http://pubchem.ncbi.nlm.nih.gov) showed that the cytotoxic potency of the C-18 fatty acids was related to their degree of conformational similarity to our cytotoxic reference compound, punicic acid, based on optimized shape (ST) and feature (CT) similarity scores, with jacaric acid being most 'biosimilar' (ST(ST-opt)=0.81; CT(CT-opt)=0.45). This 3-D analysis of structural similarity enabled us to rank geoisomeric fatty acids according to cytotoxic potency, whereas a 2-D positional assessment of cis/trans structure did not. Our findings provide mechanistic evidence that nutrition-derived non-essential fatty acids have chemopreventive biological activities and Exhibit 3-D structure-activity relationships that could be exploited to develop new strategies for the prevention or treatment of prostate cancer regardless of hormone dependency.

Dietary intervention for oral allergy syndrome as a treatment in orofacial granulomatosis: a new approach?

BACKGROUND: Orofacial granulomatosis (OFG) is a chronic granulomatous condition of the mouth, face and lips. Recent work demonstrates a high rate of atopy and silver birch sensitisation from skin prick testing (SPT). Oral allergy syndrome (OAS) is an acute oro-pharyngeal IgE mediated reaction, triggered by foods that cross react with pollens, most commonly silver birch. The aim of this study was to determine if patients with OFG and positive SPT to common OAS associated pollens responded to avoidance of cross reactive foods. METHODS: Patients with OFG and positive SPT to silver birch, grass, mugwort, ragweed and latex were required to avoid cross reacting foods, for 6 weeks and, in those who responded, for a total of 12 weeks. All had standardized oral examinations and were given severity scores (SS) at each appointment. RESULTS: Twenty two of 47 (47%) patients had one or more positive SPT and 13/22 completed 6 weeks on the diet. No difference was seen in SS between weeks 0 (14.62 ± 11.16) and 6 (13.31 ± 10.33; P = 0.656). Six of 14 (43%) had significantly improved SS (week 0; 19.17 ± 12.95, week 6; 10.83 ± 4.99, P = 0.027). Five completed 12 weeks and no further improvement was seen (week 6; 11 ± 5.57, week 12; 10.4 ± 9.94; P = 0.068). Two patients required no further treatments. CONCLUSIONS: On an intention to treat basis, only 2/14 patients improved and required no further intervention. Whilst this diet cannot be recommended routinely, the improvement seen in some patients raises questions about the role of OAS in patients with OFG.

Review article: cinnamon- and benzoate-free diet as a primary treatment for orofacial granulomatosis.

BACKGROUND: Orofacial granulomatosis is a rare chronic granulomatous inflammatory disease of the lips, face and mouth. The aetiology remains unclear but may involve an allergic component. Improvements have been reported with cinnamon- and benzoate-free diets. AIMS: To explore the prevalence of compound and food sensitivity and examine the dietary treatments used in orofacial granulomatosis. METHODS: A comprehensive literature search was carried out and relevant studies from January 1933 to January 2010 were identified using the electronic database search engines; AGRIS 1991-2008, AMED 1985-2008, British Nursing and Index archive 1985-2008, EMBASE 1980-2008, evidence based medicine review databases (e.g. Cochrane DSR), International Pharmaceutical and Medline 1950-2008. RESULTS: Common sensitivities identified, predominantly through patch testing, were to benzoic acid (36%) food additives (33%), perfumes and flavourings (28%), cinnamaldehyde (27%), cinnamon (17%), benzoates (17%) and chocolate (11%). The cinnamon- and benzoate-free diet has been shown to provide benefit in 54-78% of patients with 23% requiring no adjunctive therapies. A negative or positive patch test result to cinnamaldehyde, and benzoates did not predict dietary outcome. The most concentrated source of benzoate exposure is from food preservatives. Use of liquid enteral formulas can offer a further dietary therapy, particularly in children with orofacial granulomatosis. CONCLUSION: Management of orofacial granulomatosis is challenging but cinnamon- and benzoate-free diets appear to have a definite role to play.

Growth inhibitory, antiandrogenic, and pro-apoptotic effects of punicic acid in LNCaP human prostate cancer cells.

Prostate cancer is a commonly diagnosed cancer in men, and dietary chemoprevention by pomegranate (Punica granatum) extracts has shown noticeable benefits. In this study, we investigated the growth inhibitory, antiandrogenic, and pro-apoptotic effects of 13 pure compounds found in the pomegranate in androgen-dependent LNCaP human prostate cancer cells. Cells deprived of steroid hormones were exposed to increasing concentrations (1-100 µM) of pomegranate compounds in the presence of 0.1 nM dihydrotestosterone (DHT), and the inhibition of cell growth was measured by WST-1 colorimetric assay after a 4 day exposure. Four compounds, epigallocatechin gallate (EGCG), delphinidin chloride, kaempferol, and punicic acid, were found to inhibit DHT-stimulated cell growth at concentrations of 10 µM and above. These four pomegranate compounds inhibited DHT-stimulated androgen receptor nuclear accumulation and the expression of the androgen receptor-dependent genes prostate specific antigen and steroid 5α-reductase type 1 at concentrations ≥10 µM. We determined the possible contribution of apoptosis to the observed decrease in cell growth and found that three compounds, EGCG, kaempferol, and, in particular, punicic acid, induced DNA fragmentation after a 24 h treatment, at concentrations in the 10-100 µM range. Punicic acid, an important fatty acid in pomegranate seeds, was further found to induce intrinsic apoptosis via a caspase-dependent pathway. In conclusion, punicic acid, the main constituent of pomegranate seed (70-80%), exhibited potent growth inhibitory activities in androgen-dependent LNCaP cells, which appear to be mediated by both antiandrogenic and pro-apoptotic mechanisms.

Mixture effects of estrogenic compounds on proliferation and pS2 expression of MCF-7 human breast cancer cells.

Humans are exposed to a variety of food-borne phytochemicals (PC) as well as synthetic chemicals (SC). Some of these compounds have been reported to have estrogenic or anti-estrogenic properties and are therefore suspected endocrine disruptors. Until now it remains unclear if non-additive effects occur in combinations with endogenous estrogens, such as 17beta-estradiol (E(2)). To investigate such interactions, several PC and SC were tested individually, in mixtures and as combinations of mixtures with E(2) for effects on ERalpha receptor mediated cell proliferation and estrogen regulated pS2 expression level in MCF-7(bus) cells. PCs (coumestrol, genistein, naringenin, catechin, epicatechin, quercetin) or SCs (4-nonylphenol, octylphenol, beta-hexachlorocyclohexane, bisphenol A, methoxychlor, dibutyl phthalate) were mixed (PCmix and SCmix) either in concentrations reflecting human serum concentrations or at equipotent concentrations for estrogenicity. EC(50) values were applied in two approaches of the concentration-addition model (the method of isoboles and the cumulative estrogen equivalency method) to assess mixture effects. In both models PCmix and SCmix or combinations of the mixtures with E(2) showed no departure from additivity. In conclusion, the tested PCs and SCs appeared to act as (full) agonists for the estrogen receptor and interacted in mixtures and with estradiol in an additive way. In addition, it is concluded that the possible contribution of food-borne PCs to the estrogenic effect of xenobiotics is likely to be more significant than that caused by food-borne SCs.

Estrogenic effects of mixtures of phyto- and synthetic chemicals on uterine growth of prepubertal rats.

Through the diet humans are exposed to many weak estrogenic phytochemicals (PCs) and synthetic chemicals (SCs), but most experimental studies used individual compounds rather than mixtures. Estrogenic effects were determined in the rat juvenile uterotrophic assay using a predefined phytochemical mixture (PCmix) containing coumestrol, genistein, naringenin, (+,-)catechin, (-,-)epicatechin and quercetin, and a predefined synthetic chemical mixture (SCmix) containing nonyl-, and octylphenol, beta-hexachlorocyclohexane, methoxychlor, bisphenol A and dibutylphthalate. The mixture composition was based on human dietary uptake and actual ratios in serum. 17beta-Estradiol and genistein were also tested individually. It was found that combinations of phytoestrogens and exogenous 17beta-estradiol act additive. In contrast SCmix, inactive by itself even at high dose levels relative to human exposure, caused no synergistic or antagonistic uterotrophic effect with E(2) and/or the PCmix. Based on ED(05) and ED(01) values of the PCmix the margin of exposure in regular human diet for a uterotrophic effect is estimated many orders of magnitude. However, food supplements with phytochemicals might bring individual exposure around ED(05) and ED(01) values of the PCmix. Based on the results of our study the contribution of SCs to total estrogenicity in human diet can probably be neglected.

Variation in antibiosis ability, against potato pathogens, of bacterial communities recovered from the endo- and exoroots of potato crops produced under conventional versus minimum tillage systems.

The culturable component of bacterial communities found in the endoroot and associated exoroot (root zone soil) was examined in potatoes (Solanum tuberosum L.) grown under either conventional or minimum tillage systems. Bacterial species--abundance relationships were determined and in vitro antibiosis ability investigated to discover whether tillage practice or bacteria source (endo- or exoroot) influenced bacterial community structure and functional versatility. Antibiosis abilities against Phytophthora erythroseptica Pethyb. (causal agent of pink rot of potatoes), Streptomyces scabies (Thaxt.) Waksm. and Henrici) (causal agent of potato common scab), and Fusarium oxysporum Schlecht. Emend. Snyder and Hansen (causal agent of fusarium potato wilt) were selected as indicators of functional versatility. Bacterial community species richness and diversity indices were significantly greater (P = 0.001) in the exoroot than in the endoroot. While both endo- and exoroot communities possessed antibiosis ability against the phytopathogens tested, a significantly greater proportion (P = 0.0001) of the endoroot population demonstrated antibiosis ability than its exoroot counterpart against P. erythroseptica and F. oxysporum. Tillage regime had no significant influence on species-abundance relationships in the endo- or exoroot but did influence the relative antibiosis ability of bacteria in in vitro challenges against S. scabies, where bacteria sourced from minimum tillage systems were more likely to have antibiosis ability (P = 0.0151). We postulate that the difference in the frequency of isolates with antibiosis ability among endoroot versus exoroot populations points to the adaptation of endophytic bacterial communities that favour plant host defence against pathogens that attack the host systemically.

Histidine nutrition and genotype affect cataract development in Atlantic salmon, Salmo salar L.

The aim of this study was to investigate effects of dietary levels of histidine (His) and iron (Fe) on cataract development in two strains of Atlantic salmon monitored through parr-smolt transformation. Three experimental diets were fed: (i) a control diet (CD) with 110 mg kg(-1) Fe and 11.7 g kg(-1) His; (ii) CD supplemented with crystalline His to a level of 18 g kg(-1) (HD); and (iii) HD with added iron up to 220 mg kg(-1) (HID). A cross-over design, with two feeding periods was used. A 6-week freshwater (FW) period was followed by a 20-week period, of which the first three were in FW and the following 17 weeks in sea water (SW). Fish were sampled for weighing, cataract assessment and tissue analysis at five time points. Cataracts developed in all groups in SW, but scores were lower in those fed high His diets (P < 0.05). This effect was most pronounced when HD or HID was given in SW, but was also observed when these diets were given in FW only. Histidine supplementation had a positive effect on growth performance and feed conversion ratio (P < 0.05), whereas this did not occur when iron was added. Groups fed HD or HID had higher lens levels of His and N-acetyl histidine (NAH), the latter showing a marked increase post-smoltification (P < 0.05). The HD or HID groups also showed higher muscle concentrations of the His dipeptide anserine (P < 0.05). There was a strong genetic influence on cataract development in the CD groups (P < 0.001), not associated with tissue levels of His or NAH. The role of His and His-related compounds in cataractogenesis is discussed in relation to tissue buffering, osmoregulation and antioxidation.

Persistence of the antihypertensive efficacy of amlodipine and nifedipine GITS after two 'missed doses': a randomised, double-blind comparative trial in Asian patients.

Suboptimal management of hypertension is often a result of poor patient compliance in the form of missed doses of their antihypertensive medication. This multicentre, randomised, double-blind, parallel-group trial was designed to compare the persistence of the antihypertensive efficacy of the amlodipine and nifedipine gastrointestinal therapeutic system (GITS) after two 'missed doses', and also to compare the drugs' overall efficacy and safety in Asian patients with mild-to-moderate essential hypertension. Following a 2-week placebo run-in period, 222 patients were randomised to receive either amlodipine (5 mg daily, increased after 6 weeks if necessary to 10 mg daily, n=109) or nifedipine GITS (30 mg daily, increased after 6 weeks if necessary to 60 mg daily; n=113) for 12 weeks. A placebo was then substituted for further 2 days with continuous ambulatory blood pressure (BP) monitoring. The increases in the last 9 h of mean ambulatory BP on day 2 after treatment withdrawal were significantly less with amlodipine than with nifedipine GITS: 4.4+/-7.0 vs 11.2+/-11.3 mmHg for systolic BP (P

Preclinical evaluation of a humanized NR-LU-10 antibody-streptavidin fusion protein for pretargeted cancer therapy.

A humanized single chain Fv antibody fragment specific to the EGP40 antigen was genetically engineered as a streptavidin fusion (scFvSA) for use in pretargeted radioimmunotherapy. The scFvSA construct was expressed as a soluble, tetrameric species in the Escherichia coli periplasm at 110-140 mg/liter. The fusion protein was purified from crude lysates by iminobiotin affinity chromatography with an overall yield of 50-60%. Characterization of the purified protein by SDS-PAGE, light scattering, and size exclusion chromatography demonstrated that the fusion protein was tetrameric with a molecular weight of approximately 172,000. Competitive immunoreactivity assays showed a two-fold greater binding to the antigen than the comparable whole antibody. The purified protein had a biotin disassociation rate identical to recombinant streptavidin and bound an average of three of four possible biotins per molecule. The radiolabeled fusion protein showed a faster blood clearance rate in normal mice than the corresponding whole antibody-streptavidin chemical conjugate. Tumor-specific targeting of a subsequently administered radionuclidechelate/biotin molecule was demonstrated in nude mice bearing SW1222 human colon carcinoma xenografts. A single dose of 800 microCi of 90Y-DOTA-biotin produced cures in mice with established subcutaneous human small cell lung or colon cancer xenografts.

Selective adhesion, lipid exchange and membrane-fusion processes between vesicles of various sizes bearing complementary molecular recognition groups.

Equimolar mixtures of large unilamellar vesicles (LUVs) obtained from mixtures of egg lecithin and lipids containing complementary hydrogen bonding head groups (barbituric acid (BAR) and 2,4,6-triaminopyrimidine (TAP)) were shown to aggregate and fuse. These events have been studied in detail using electron microscopy and dynamic light scattering, and by fluorimetry using membrane or water-soluble fluorescence probes. It was shown that aggregation was followed by two competitive processes: a) lipid mixing leading to redispersion of the vesicles; b) fusion events generating much larger vesicles. In order to better understand the nature of the interaction, the effects of ionic strength and surface concentration of recognition lipids on the aggregation process were investigated by dynamic light scattering. Additionally, it was possible to inhibit the aggregation kinetics through addition of a soluble barbituric acid competitor. The study was extended to giant unilamellar vesicles (GUVs) to investigate the size effect and visualise the phenomena in situ. The interactions between complementary LUVs and GUVs or GUVs and GUVs were studied by optical microscopy using dual fluorescent labelling of both vesicle populations. A selective adhesion of LUVs onto GUVs was observed by electron and optical microscopies, whereas no aggregation took place in case of a GUV/GUV mixture. Furthermore, a fusion assay of GUV and LUV using the difference of size between GUV and LUV and calceine self-quenching showed that no mixing between the aqueous pools occured.

A human lens model of cortical cataract: Ca2+-induced protein loss, vimentin cleavage and opacification.

PURPOSE: Cortical cataract in humans is associated with Ca2+ overload and protein loss, and although animal models of cataract have implicated Ca2+-activated proteases in this process, it remains to be determined whether the human lens responds in this manner to conditions of Ca2+ overload. The purpose of these experiments was to investigate Ca2+-induced opacification and proteolysis in the organ-cultured human lens. METHODS: Donor human lenses were cultured in Eagle's minimum essential medium (EMEM) for up to 14 days. The Ca2+ ionophore ionomycin was used to induce a Ca2+ overload. Lenses were loaded with [3H]-amino acids for 48 hours. After a 24-hour control efflux period, lenses were cultured in control EMEM (Ca2+ 1.8 mM), EMEM + 5 microM ionomycin, or EMEM + 5 microM ionomycin + 5 mM EGTA (Ca2+ < 1 microM). Efflux of proteins and transparency were monitored daily. Protein distribution and cytoskeletal proteolysis were analyzed at the end of the experiment. Cytoskeletal proteins were isolated and separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Western blot analyses were probed with anti-vimentin antibody (clone V9) and detected by enhanced chemiluminescence. RESULTS: Lenses cultured under control conditions remained transparent for 14 days in EMEM with no added supplements or serum. The lenses synthesized proteins and had a low rate of protein efflux throughout the experimental period. Ionomycin treatment resulted in cortical opacification, which was inhibited when external Ca2+ was chelated with EGTA. Exposure to ionomycin also led to an efflux of [3H]-labeled protein, amounting to 41% of the labeled protein over the 7-day experimental period, compared with 12% in ionomycin + EGTA-treated lenses. Efflux was accounted for by loss from the lens soluble protein (crystallin) fraction. Western blot analysis of the cytoskeletal protein vimentin (56 kDa) revealed a distinct breakdown product of 48 kDa in ionomycin-treated lenses that was not present when Ca2+ was chelated with EGTA. In addition, high-molecular-weight proteins (approximately 115 kDa and 235 kDa) that cross-reacted with the vimentin antibody were observed in ionomycin-treated lenses. The Ca2+-induced changes were not age dependent. CONCLUSIONS: Human lenses can be successfully maintained in vitro, remaining transparent for extended periods. Increased intracellular Ca2+ induces cortical opacification in the human lens. Ca2+-dependent cleavage and cross-linking of vimentin supports possible roles for calpain and transglutaminase in the opacification process. This human lens calcium-induced opacification (HLCO) model enables investigation of the molecular mechanisms of opacification, and the data help to explain the loss of protein observed in human cortical cataractous lenses in vivo.

Folic acid improves arterial endothelial function in adults with hyperhomocystinemia.

OBJECTIVES: To evaluate whether oral folic acid supplementation might improve endothelial function in the arteries of asymptomatic adults with hyperhomocystinemia. BACKGROUND: Hyperhomocystinemia is an independent risk factor for endothelial dysfunction and occlusive vascular disease. Folic acid supplementation can lower homocystine levels in subjects with hyperhomocystinemia; however, the effect of this on arterial physiology is not known. METHODS: Adults subjects were recruited from a community-based atherosclerosis study on healthy volunteers aged 40 to 70 years who had no history of hypertension, diabetes mellitus, hyperlipidemia, ischemic heart disease or family history of premature atherosclerosis (n = 89). Seventeen subjects (aged 54 +/- 10 years, 15 male) with fasting total homocystine levels above 75th percentile (mean, 9.8 +/- 2.8 micromol/liter) consented to participate in a double-blind, randomized, placebo-controlled and crossover trial; each subject received oral folic acid (10 mg/day) and placebo for 8 weeks, each separated by a washout period of four weeks. Flow-mediated endothelium-dependent dilation (percent increase in diameter) of the brachial artery was assessed by high resolution ultrasound, before and after folic acid or placebo supplementation. RESULTS: Compared with placebo, folic acid supplementation resulted in higher serum folate levels (66.2 +/- 7.0 vs. 29.7 +/- 14.8 nmol/liter; p < 0.001), lower total plasma homocystine levels (8.1 +/- 3.1 vs. 9.5 +/- 2.5 micromol/liter, p = 0.03) and significant improvement in endothelium-dependent dilation (8.2 +/- 1.6% vs. 6 +/- 1.3%, p < 0.001). Endothelium-independent responses to nitroglycerin were unchanged. No adverse events were observed. CONCLUSION: Folic acid supplementation improves arterial endothelial function in adults with relative hyperhomocystinemia, with potentially beneficial effects on the atherosclerotic process.

The role of imagination in facilitating deductive reasoning in 2-, 3- and 4-year-olds.

When 4- and 6-year-olds are cued to use their imagination, they can overcome the belief bias effect and demonstrate deductive reasoning ability on syllogisms containing contrary-to-fact material. This study tested whether 2- and 3-year-olds could also reason with incongruent syllogisms when encouraged to use their imagination. Eighty-four 2-, 3- and 4-year-olds were randomly assigned to one of four conditions: no cue, word cue, fantasy planet or imagery. Children were then presented with six syllogistic reasoning problems containing incongruent information. In the imagination conditions, 2- and 3-year-olds performed as competently as 4-year-olds. The findings are discussed in relation to other research which suggests that under certain circumstances 2- and 3-year-olds have the capacity for counterfactual thinking.

Chinese herbs and warfarin potentiation by 'danshen'.

Drug interactions with warfarin can be dangerous and although common drug interactions are now well recognized those with Chinese herbs are not widely appreciated. 'Danshen' is a herbal medicine often used for various complaints, particularly cardiovascular, in the Chinese community. We report a case of danshen-induced overcoagulation with severe and dangerous abnormalities of clotting in a patient with rheumatic heart disease.

The effect of transcutaneous electrical nerve stimulation on coronary and systemic haemodynamics in syndrome X.

BACKGROUND: Neurostimulation techniques have been shown to be beneficial in patients with angina and syndrome X but the mechanism remains unclear. We examined the effect of transcutaneous electrical nerve stimulation (TENS) on coronary artery blood flow in a group of patients with syndrome X. METHODS: Coronary blood flows were measured in 11 patients with angiographically normal coronary arteries, positive results from exercise tests and angina (syndrome X) using intracoronary Doppler catheters combined with quantitative coronary angiography. RESULTS: The mean coronary flow velocity did not increase in any patient during TENS therapy; in fact, there was a fall from 5.2 +/- 2.8 to 4.3 +/- 1.9 cm/s (P = 0.02) and the coronary blood flow index fell from 47 +/- 22 to 38 +/- 16 cm/s per mm2 (P = 0.007). This was associated with a fall in the rate x pressure product from 0.92 +/- 0.22 to 0.83 +/- 0.18 mmHg/min (P = 0.038). The coronary vascular resistance rose from 2.4 +/- 1.1 to 3.0 +/- 1.6 mmHg/cm per s per mm2 (P = 0.041). There were no major changes in the epicardial coronary artery diameter during TENS and there was no significant effect on the response to the cold-pressor test. CONCLUSIONS: In this group of patients with syndrome X, TENS produced a small but significant fall in coronary artery blood flow associated with a reduction in the rate x pressure product. TENS had no significant effect on coronary vasomotion during sympathetic stimulation by the cold-pressor test. Thus, TENS is unlikely to have a direct effect on coronary artery vasomotion or haemodynamics in syndrome X but reduces the rate x pressure product and thus myocardial oxygen consumption.

Calcium localization and ultrastructure of clear and pCMPS-treated rat lenses.

PURPOSE: The sulfhydryl complexing agent p-chloromercuri-phenylsulfonate (pCMPS) has been shown to increase lens membrane permeability, Na+ and Ca2+ content, and light scatter in the rat lens in vitro. This study aimed to investigate the ultrastructural changes accompanying the increase in light scatter. In addition, high-resolution histochemistry was used to study the cellular distribution of Ca2+ in normal and cataractous lenses. METHODS: Rat lenses were incubated for 4 hours in normal (1 mM) and high (5 mM) Ca2+ containing media supplemented with 40 microM pCMPS. Control lenses were incubated in 1 mM Ca2+ containing medium. They were prepared for scanning and transmission electron microscopy and for Ca2+ localization using the oxalate-pyroantimonate procedure. RESULTS: Control lenses incubated for 4 hours had normal morphology and showed no evidence of light scatter. Calcium distribution as observed with the oxalate-pyroantimonate precipitation method was low in superficial fibers, high in the membranes of intermediate fibers, and declined again toward the nucleus. In the deeper cortex, there also were small vacuoles of calcium accumulation. pCMPS treatment (in 1 and 5 mM Ca2+) induced a significant influx of calcium into the lens cytoplasm. Calcium-containing extracellular vacuoles also were seen in the intermediate cortex in both cases. The presence of these vacuoles appeared to correlate with the major areas of light scatter in the lens. In 5 mM Ca2+, intracellular vacuoles were observed throughout the superficial cortex. CONCLUSIONS: Most of the calcium observed by oxalate-pyroantimonate in the normal lens is located at the membrane, and the staining appears strongest in the intermediate cortex. In pCMPS treatment, large extracellular vacuoles are present in this intermediate zone and appear to be the major source of light scatter. This zone may be the initiation site of many different types of cataract, including some described in human lenses.

N-methyl-D-aspartate R1 messenger RNA and [125I]MK-801 binding decrease in rat spinal cord after unilateral hind paw inflammation.

Recent evidence suggests that N-methyl-D-aspartate receptors play an important role in the etiology and maintenance of chronic nociception. Previous studies have demonstrated that tissue injury or stimulation of nociceptive afferent projections results in the expansion of receptive fields, hyperalgesia and C-fiber-induced wind-up, events that can be inhibited by N-methyl-D-aspartate antagonists. This study examines the effect of unilateral hind paw inflammation on N-methyl-D-aspartate R1 messenger RNA and [125I]dizocilpine maleate binding in the L4-L5 segments of the lumbar spinal cord of rats. Spinal cords were examined at 7.5 h, three, seven and 20 days after injection of the left hind paw with 120 microliters of complete Freund's adjuvant. N-methyl-D-aspartate R1 messenger RNA, as measured with in situ hybridization, was observed to decrease bilaterally in laminae I, II and X of the lumbar spinal cord. This decrease was evident in laminae I and II at 7.5 h and three days after hind paw injection. In lamina X, a postinjection decrease in hybridization signal was observed at 7.5 h and seven days. A bilateral decrease in [125I]dizocilpine maleate binding was observed in laminae I and II at three, seven and 20 days after paw injection. This observed decrease in binding at the N-methyl-D-aspartate receptor suggests a compensatory mechanism by which N-methyl-D-aspartate-mediated nociceptive events may be modulated.

The effect of transcutaneous electrical nerve stimulation (TENS) on autonomic cardiovascular reflexes.

Transcutaneous electrical nerve stimulation (TENS) has been shown to have an anti-ischaemic effect in patients with angina and peripheral vascular disease that appears to be additional to any analgesic action. The mechanism for this anti-ischaemic effect is not known but it is possible that TENS interferes with the autonomic responses to ischaemia. To determine if TENS has any direct action on autonomic reflexes we have assessed the effect of high frequency TENS on a variety of standard tests of autonomic cardiovascular reflexes in 10 normal subjects. Tests were done on four consecutive days at the same time and TENS therapy or placebo was randomly allocated on 2 days each. Results of the tests were assessed by one person 'blinded' to the randomization order. These showed that TENS was associated with a significant reduction in the rise of the diastolic blood pressure (21.8 +/- 2.3 v. 17.6 +/- 17 mmHg; p < 0.05) during isometric exercise, using sustained Handgrip. There was no significant effect discernible on the changes of heart rate and blood pressure during the Valsalva manoeuvre, cold face stimulus or head-up tilt. Transcutaneous electrical nerve stimulation appears, therefore, to have a mild inhibitory action on those reflexes mediated predominantly by the sympathetic nervous system and this is more apparent when the stimulation may be greater, as during isometric exercise.