Stress and skin disease quality of life: the moderating role of anxiety sensitivity social concerns.

BACKGROUND: Stress is an important factor in the onset, exacerbation and reoccurrence of many skin diseases. Little is known about psychological risk factors that affect the association between stress and dermatological conditions. One relevant factor that may modulate this link is anxiety sensitivity (AS) social concerns - the propensity to respond fearfully to anxiety-related sensations (e.g. sweating, flushing) owing to perceived social consequences (e.g. rejection or humiliation). OBJECTIVES: To gain insight into psychological factors affecting skin disease, we examined the moderating role of AS social concerns in the relationship between stress and skin disease quality of life (QoL). METHODS: Participants [n = 237 (161 female), mean ± SD age 34·18 ± 9·57 years] with active skin disease symptoms were recruited online and completed questionnaires assessing stress, AS social concerns, skin disease QoL and global skin disease symptom severity. RESULTS: AS social concerns moderated the association between stress and skin-related emotional and social functioning in adults with skin disease. Stress was a significant predictor of the impairment associated with skin disease. CONCLUSIONS: Stress was linked to skin disease-related emotional and functional impairment associated with skin disease among individuals with high AS social concerns. These results highlight the potential for AS reduction interventions to break the vicious cycle of stress and skin disease symptoms and to improve psychosocial well-being in dermatology patients.

Four-jet production at the Large Hadron Collider at next-to-leading order in QCD.

We present the cross sections for production of up to four jets at the Large Hadron Collider, at next-to-leading order in the QCD coupling. We use the BLACKHAT library in conjunction with SHERPA and a recently developed algorithm for assembling primitive amplitudes into color-dressed amplitudes. We adopt the cuts used by ATLAS in their study of multijet events in pp collisions at √s=7 TeV. We include estimates of nonperturbative corrections and compare to ATLAS data. We store intermediate results in a framework that allows the inexpensive computation of additional results for different choices of scale or parton distributions.

Precise predictions for W+4-jet production at the large hadron collider.

We present the next-to-leading order (NLO) QCD results for W+4-jet production at hadron colliders. This is the first hadron-collider process with five final-state objects to be computed at NLO. It represents an important background to many searches for new physics at the energy frontier. Total cross sections, as well as distributions in the jet transverse momenta, are provided for the initial LHC energy of √s = 7 TeV. We use a leading-color approximation, known to be accurate to 3% for W production with fewer jets. The calculation uses the BLACKHAT library along with the SHERPA package.

First Report of Leaf Rust of Blueberry Caused by Thekopsora minima in Mexico.

Blueberry (Vaccinium corymbosum L.) is becoming an important crop in the states of Jalisco and Michoacan in Mexico. Leaf rust, a disease causing extensive defoliation on plants with severe infections, was observed in the autumn of 2007 and it has become one of the most significant diseases of blueberry in these states. Symptoms on the upper surfaces of leaves appear as small, yellow spots that later turn necrotic as they enlarge and coalesce and eventually cover large areas of individual leaves. On the undersides of leaves, small flecks surrounded by small water-soaked halos appear, turn yellow, and produce powdery sori that are uredinia with urediniospores. Uredinia were hypophyllous, scattered to gregarious and at times superficially appearing confluent, up to about 300 µm in diameter, dome shaped and peridium hemispherical in cross section, orangish, becoming pulverulent, lacking obviously enlarged, well-differentiated ostiolar cells. Urediniospores were subglobose, obovate, oblong or ellipsoid, 17.6 to 27.2 × 12.8 to 17.6 µm, with hyaline, echinulate walls that are 1.2 to 1.8 µm thick, and with yellow-to-hyaline contents. Telia were not observed. On the basis of uredinial morphology (3,4), the rust was identified as Thekopsora minima P. Syd. & Syd. To distinguish this rust from other rust species causing disease on Vaccinium (2,3), a 1,414-bp region consisting of ITS2 and the 5' end of the 28S was amplified with primers Rust2inv/LR6 from uredinial lesions on infected leaves of V. corymbosum 'Biloxi' and sequenced (BPI 880580; GenBank Accession No. HM439777) (1). Results of a BLAST search of GenBank found 100% (1,414 of 1,414) identity to T. minima (GenBank Accession No. GU355675) from South Africa (3). Pathogenicity tests were completed as follows: (i) during the autumn of 2009, rusted leaves of cvs. Biloxi and Sharpblue were collected from the field; (ii) mature leaves from healthy plants of both blueberry cultivars were surface disinfested with 1% sodium hypochlorite for 2 min and rinsed with sterile distilled water; (iii) fresh urediniospores from rusted leaves were brushed directly onto the undersides of disinfested detached leaves; (iv) to avoid drying, wet cotton balls were placed on the petioles of inoculated leaves that were subsequently placed in resealable plastic bags; and (v) leaves were then incubated in a growth chamber at 22°C with a 12-h photoperiod. For each cultivar, 20 leaves were inoculated and five uninoculated leaves were included as controls and the test was repeated once. Yellow uredinia were observed 13 and 10 days after inoculation in cvs. Biloxi and Sharpblue, respectively. Leaf symptoms and uredinial characters were the same as observed previously in the field. To our knowledge, this is the first report of T. minima in Mexico. This report is significant for growers who need a diagnosis to control the disease and for breeders and plant pathologists who should consider developing more resistant cultivars. References: (1) M. C. Aime. Mycoscience 47:112, 2006. (2) F. L. Caruso and D. C. Ramsdell, eds. Compendium of Blueberry and Cranberry Diseases. The American Phytopathological Society, St. Paul, MN, 1995. (3) L. Mostert et al. Plant Dis. 94:478, 2010. (4) P. Sydow and H. Sydow. Monographia Uredinearum. Vol. III. Fratres Borntraeger, Leipzig, Germany, 1915.

First Report of Juneberry Rust Caused by Gymnosporangium nelsonii on Juneberry in Michigan.

Amelanchier alnifolia (Nutt.) Nutt. ex M. Roem., commonly known as juneberry or Saskatoon serviceberry, was historically a widely used prairie fruit that is native to the Northern Great Plains, southern Yukon and Northwest Territories (4). While juneberry is an important fruit crop in the prairie provinces of Canada, small commercial plantings also occur throughout the northern United States (2), including Michigan. On July 18, 2009, severe rust symptoms were observed on plants in a 2-year-old field of A. alnifolia 'Northline' in Northport, MI. The plants had been sourced as seedlings from a nursery in Alberta, Canada in 2007. Signs and symptoms were present on fruits and leaves on virtually all of the plants. Symptomatic fruit were still immature, and on average, more than 70% of the fruit surface was covered with tubular, whitish aecia with conspicuous orange aeciospores. Portions of twigs also showed fusiform swellings (1 to 3 cm long) covered with aecia. Aecia were hypophyllous, fructicolous and caulicolous, roestelioid, and 2 to 4 mm high. The peridium was cylindric and tapering toward the apex, dehiscent at the apex, retaining a tubular shape for a long time and at times becoming lacerated on the sides with age. Peridial cells were linear rhomboidal, 50 to 105 µm long, hyaline to brownish, outer walls smooth, inner walls with small papillae, and side walls delicately verrucose-rugose with elongate papillae having variable lengths. Aeciospores were globoid, 20 to 35 × 25 to 38 µm (average 30.7 × 32.5 µm), orange to cinnamon brown, and densely verrucose with walls 2.5 to 3.5 µm thick. On the basis of these morphological characters, the host, and comparison with a reference specimen (BPI 122010), the pathogen was identified as Gymnosporangium nelsonii Arthur (1,3). The 5' region of the 28S rDNA was sequenced (GenBank Accession No. HM591299.1), confirming the identification as a species of Gymnosporangium, one distinct from previously sequenced specimens available in GenBank. The specimen has been deposited at the U.S. National Fungus Collections (BPI 880671 and 880709). Four other species found previously on Amelanchier spp. in the Midwest differ as follows: G. clavipes and G. clavariiforme have verrucose peridial cells and different 28S rDNA sequences; G. nidus-avis has rugose peridial cells; and G. corniculans has cornute peridia that dehisce from lateral slits while apices remain intact and verrucose peridial walls with verrucae on the side walls (1). The infection was likely caused by basidiospores originating from telia on Juniperus spp. in the area surrounding the field. However, no telia of G. nelsonii were found on junipers in the immediate vicinity. To our knowledge, this is the first report of G. nelsonii on juneberry in Michigan and the Midwest. Because of the devastating impact of this disease on fruit quality, fungicide programs have been devised for disease control and were effective in 2010. Juneberry growers in the Midwest need to be aware of this disease and monitor their crop carefully for symptoms and signs. References: (1) F. D. Kern. A Revised Taxonomic Account of Gymnosporangium. Pennsylvania State University Press, University Park, 1973. (2) K. Laughlin et al. Juneberry for Commercial and Home Use on the Northern Great Plains. North Dakota State University, Fargo 1996. (3) S. K. Lee and M. Kakishima. Mycoscience 40:121, 1999. (4) G. Mazza and C. G. Davidson. Page 516 in: New Crops. Wiley, New York, 1993.

First Report of the Telial Stage of Japanese Apple Rust on Juniperus chinensis in North America and the Aecial Stage on Malus domestica.

Following a report in April 2009 of the presence of Gymnosporangium yamadae Miyabae ex G. Yamada on crabapple (Malus toringo Siebold) in Wilmington, DE (2), University of Delaware, State of Delaware, and USDA/APHIS PPQ personnel collaborated to confirm and document the pathogen. G. yamadae is the causal agent of Japanese apple rust. The fungus is known from Asia with an aecial state on economically important Malus species and telial state on Juniperus chinensis. During the April 2009 site visit, ornamental J. chinensis were observed near the original crabapples. On May 7, 2009, telial galls were collected from the ornamental J. chinensis at the Wilmington site. The telia were confirmed to be G. yamadae by morphometric analysis and molecular data. The rDNA large subunit (LSU) sequence derived from the collected telial galls (GenBank Accession No. GU058012) was identical to the eight G. yamadae LSU sequences (GenBank Accession Nos. FJ848760-FJ848765, FJ559373, and FJ559375) reported from Korea by Yun et al. (3). Teliospores were 45 to 54 µm long with pedicels that were wide (7.0 to 8.4 µm) along the full length. The G. yamadae telial gall collected from Wilmington, DE was deposited into the U.S. National Fungus Collection (BPI 879273). Leaves of M. domestica on the University of Delaware farm in Newark were confirmed to have Japanese apple rust on Aug 4, 2009. Identification was made on the morphological presence of unique roestelioid aecia with long cornulated peridia that lacerate along the sides. The aecia differ from those of G. juniperi-virginianae, the causal agent of cedar apple rust, which has aecial peridia that fimbriate to the base and are strongly recurved (1). Following release of a USDA Pest Alert, subsequent samples submitted to USDA/APHIS PPQ indicated widespread incidence of the G. yamadae aecial state in the northeast, including Maryland, Maine, New Hampshire, New Jersey, New York, Pennsylvania, and Rhode Island. Japanese apple rust likely went undetected for several years because of similar symptomatology to cedar apple rust. To our knowledge, this is the first report of the telial stage of G. yamadae in North America and the first report of this pathogen on Malus domestica in the United States. Knowledge of the geographic distribution of G. yamadae is of significance because of the actionable regulatory status of the pathogen and its potential impact on ornamental and fruit growers of Malus spp. in the United States. References: (1) F. D. Kern. A Revised Taxonomic Account of Gymnosporangium. Pennsylvania State University Press, University Park, PA, 1973. (2) H. Y. Yun et al. Plant Dis. 93:430, 2009. (3) H. Y. Yun et al. Mycologia 101:790, 2009.

Uromyces ciceris-arietini, the Cause of Chickpea Rust: New Hosts in the Trifolieae, Fabaceae.

Uromyces ciceris-arietini has been reported on Cicer arietinum (chickpea) and Medicago polyceratia. Plants of Medicago polymorpha in Riverside and San Diego, CA were collected with severe rust caused by U. ciceris-arietini. To confirm the identification and potential new host range, a monouredinial isolate of U. ciceris-arietini from M. polymorpha was inoculated on eight accessions each of C. arietinum and M. polyceratia. All plants showed symptoms of the disease. Consequently, a range of fabaceous hosts were evaluated for their reaction to U. ciceris-arietini. New hosts for U. ciceris-arietini included 29 species of Medicago, specifically M. arabica, M. blancheana, M. ciliaris, M. constricta, M. coronata, M. doliata, M. granadensis, M. intertexta, M. italica, M. laciniata, M. lanigera, M. lesinsii, M. lupulina, M. minima, M. murex, M. muricoleptis, M. orbicularis, M. praecox, M. radiata, M. rigidula, M. rotata, M. rugosa, M. sativa, M. sauvagei, M. scutellata, M. soleirolii, M. tenoreana, M. truncatula, and M. varia, and three species of Melilotus, specifically M. italicus, M. speciosus, and M. spicatus. This isolate of U. ciceris-arietini produced no symptoms on plants in the 33 accessions tested in the genera Anthyllis, Astragalus, Lotus, and Lupinus. DNA sequences are provided to aid in the identification of this pathogen.

First Report of Uromyces acuminatus on Honckenya peploides, the Endangered Seabeach Sandwort.

Honckenya peploides (L.) Ehrh. (Caryophyllaceae), commonly known as seabeach sandwort, is a species of special concern in Connecticut (4). Nearly an entire population of H. peploides in New London County, CT was found to be severely infected by the aecial stage of a rust fungus in June of 2008. Representative plants in the population were infected with aecia on more than 50% of the leaves. Aecia were amphigenous, gregarious, cupulate, pulverulent, yellowish, and erumpent with a hyaline to whitish peridium having a lacerate, somewhat recurved margin. Peridial cells were rhomboidal, 26 to 31 × 25 to 29 µm, smooth to finely verrucose. Aeciospores were globose to ellipsoid, 23.5 to 29 × 20.5 to 22 µm, hyaline to pale yellowish with a verrucose surface and hyaline walls 1.5 to 2 µm thick. Morphological characters corresponded to a reference specimen (BPI 000105) of the aecial stage of Uromyces acuminatus Arthur from Nova Scotia, as well as published descriptions (1,2). Subsequently, telia of U. acuminatus were discovered on Spartina patens (Aiton) Muhl. (Poaceae) in May of 2009 in New London County, CT. Telia were adaxial, intercostal, scattered to gregarious, linear and at times elongate, dark brown to black, pulverulent, and erumpent. Teliospores were obovate to ellipsoid with rounded to acuminate apices rarely having two points, 30 to 41 × 19 to 24 µm, with a smooth surface and brownish-yellow to brown walls 9 to 14 µm thick at apex, which is sometimes paler, and 1 to 3 µm thick laterally, pedicels with a portion persisting on the teliospore that is up to 82 µm long and brownish-yellow. The ITS2 and 5' region of the 28S rDNA (998 bp) from the rust on H. peploides (GenBank Accession No. GU109282, BPI 879300) and the rust on S. patens (GenBank Accession No. GU058008, BPI 879285B) were sequenced to confirm the identification of U. acuminatus on H. peploides with the resulting sequences identical. U. acuminatus is widespread in the eastern United States and Canada (1-3). The telial stage is found on Spartina spp., while the aecial stage is found on numerous taxa including members of the Asparagaceae (formerly Ruscaceae, Liliaceae), Caryophyllaceae, Polemoniaceae, and Primulaceae (1-3). Puccinia arenariae (Schumach.) G. Winter, previously reported from H. peploides (4), is microcyclic and stages 0, I, and II are unknown. To our knowledge, this is the first report of U. acuminatus on the genus Honckenya. This report has significance to natural resource conservation managers and scientists working in endangered plant habitats because H. peploides and H. peploides subsp. robusta are listed as plants of special concern or endangered/extirpated in Connecticut, Maryland, New Hampshire, and Rhode Island (4). References: (1) J. C. Arthur. Order Uredinales. N. Am. Flora 7(3):161, 1912. (2) G. B. Cummins. The Rust Fungi of Cereals, Grasses and Bamboos. Springer-Verlag, New York, 1971. (3) D. F. Farr and A. Y. Rossman. Fungal Databases. Systematic Mycology and Microbiology Laboratory. Online publication. ARS, USDA, 2009. (4) USDA, NRCS. The PLANTS Database. Online publication. National Plant Data Center, Baton Rouge, LA, 2009.

Ultraviolet behavior of N = 8 supergravity at four loops.

We describe the construction of the complete four-loop four-particle amplitude of N=8 supergravity. The amplitude is ultraviolet finite, not only in four dimensions, but in five dimensions as well. The observed extra cancellations provide additional nontrivial evidence that N=8 supergravity in four dimensions may be ultraviolet finite to all orders of perturbation theory.

Host specialization and phylogenetic diversity of Corynespora cassiicola.

The fungus Corynespora cassiicola is primarily found in the tropics and subtropics, and is widely diverse in substrate utilization and host association. Isolate characterization within C. cassiicola was undertaken to investigate how genetic diversity correlates with host specificity, growth rate, and geographic distribution. C. cassiicola isolates were collected from 68 different plant species in American Samoa, Brazil, Malaysia, and Micronesia, and Florida, Mississippi, and Tennessee within the United States. Phylogenetic analyses using four loci were performed with 143 Corynespora spp. isolates, including outgroup taxa obtained from culture collections: C. citricola, C. melongenae, C. olivacea, C. proliferata, C. sesamum, and C. smithii. Phylogenetic trees were congruent from the ribosomal DNA internal transcribed spacer region, two random hypervariable loci (caa5 and ga4), and the actin-encoding locus act1, indicating a lack of recombination within the species and asexual propagation. Fifty isolates were tested for pathogenicity on eight known C. cassiicola crop hosts: basil, bean, cowpea, cucumber, papaya, soybean, sweet potato, and tomato. Pathogenicity profiles ranged from one to four hosts, with cucumber appearing in 14 of the 16 profiles. Bootstrap analyses and Bayesian posterior probability values identified six statistically significant phylogenetic lineages. The six phylogenetic lineages correlated with host of origin, pathogenicity, and growth rate but not with geographic location. Common fungal genotypes were widely distributed geographically, indicating long-distance and global dispersal of clonal lineages. This research reveals an abundance of previously unrecognized genetic diversity within the species and provides evidence for host specialization on papaya.

Precise predictions for w+3 jet production at hadron colliders.

We report on the first next-to-leading order QCD computation of W+3-jet production in hadronic collisions including all partonic subprocesses. We compare the results with data from the Tevatron and find excellent agreement. The required one-loop matrix elements are computed using on-shell methods, implemented in a numerical program, BlackHat. We use the SHERPA package to generate the real-emission contributions and to integrate the various contributions over phase space. We use a leading-color (large-N_{c}) approximation for the virtual part, which we confirm in W+1, 2-jet production to be valid to within three percent.

A case of ST-elevation and nystagmus--when coronary thrombosis is not to blame.

We present the case of a post-menopausal female who, following a prolonged period of vomiting and diarrhoea, presented acutely with Wernicke's; encephalopathy, chest pain, ST-segment elevation and congestive cardiac failure associated with hypotension. Coronary angiography demonstrated no abnormality. Haemodynamics improved significantly in the short-term following intravenous thiamine replacement, with complete resolution of all ST-segment abnormalities and normalization of left ventricular function at six-week follow-up. Shoshin beriberi in the context of metabolic alkalosis, secondary to severe electrolyte depletion, is exceptional and is a differential diagnosis to be considered in all malnourished patients presenting with symptoms and signs suggestive of an acute coronary syndrome, especially those with a history of alcohol-dependence.

A class-wide phylogenetic assessment of Dothideomycetes.

We present a comprehensive phylogeny derived from 5 genes, nucSSU, nucLSU rDNA, TEF1, RPB1 and RPB2, for 356 isolates and 41 families (six newly described in this volume) in Dothideomycetes. All currently accepted orders in the class are represented for the first time in addition to numerous previously unplaced lineages. Subclass Pleosporomycetidae is expanded to include the aquatic order Jahnulales. An ancestral reconstruction of basic nutritional modes supports numerous transitions from saprobic life histories to plant associated and lichenised modes and a transition from terrestrial to aquatic habitats are confirmed. Finally, a genomic comparison of 6 dothideomycete genomes with other fungi finds a high level of unique protein associated with the class, supporting its delineation as a separate taxon.

First Report of Orange Rust of Sugarcane Caused by Puccinia kuehnii in Mexico, El Salvador, and Panama.

Symptoms of sugarcane orange rust were observed on July 17, 2008 on sugarcane cvs. Mex 57-1285, Mex 61-230, and Co 301 (a clone received in Mexico in 1953) at the Centro de Investigación y Desarrollo de la Caña de Azúcar en Tuxtla Chico, Chiapas, Mexico. In El Salvador, from August 2008 through January 2009, rust symptoms were observed on cv. CP 72-2086 (previously resistant to brown rust caused by Puccinia melanocephala Syd. & P. Syd.) in 117 dispersed sugarcane-production fields in various localities of El Salvador. Likewise, rust symptoms were first observed on sugarcane cv. SP 74-8355 (more than 25% severity and considered resistant to brown rust) at Natá, Coclé Province in Panama from January to February 2008. Dried herbarium leaf samples of sugarcane rust-infected leaves collected in El Salvador and Mexico were sent to the ARS, USDA Systematic Mycology and Microbiology Laboratory in Beltsville MD for identification. Panamanian samples were collected similarly and analyzed at the CALESA Biotechnology Laboratory. Morphological features of uredinial lesions and urediniospores were distinct from those of P. melanocephala and consistent with P. kuehnii E. J. Butler observed previously on specimens from Florida, Guatemala, Costa Rica, and Nicaragua (1-3). Analysis of the ITS1, 5.8S, and ITS2 and 28S large subunit rDNA sequences of the rust on infected cvs. Mex 57-1285, Mex 61-230, and Co 301 (BPI 878930, 879139, and 879140; GenBank Accession Nos. GO283006, GO283004, and GO283005, respectively) from Mexico and cv. CP 72-2086 from three locations in El Salvador (BPI 879135, 879136, and 879137; GenBank Accession Nos. GO283009, GO283007, and GO283008, respectively) all confirmed the identification of P. kuehnii. Similar analysis of the ITS1, 5.8S, and ITS2 rDNA sequence for the rust infecting cv. SP 74-8355 (GenBank Accession No. GO281584) confirmed the identification of P. kuehnii in Panama. To our knowledge, this is the first report of P. kuehnii causing orange rust disease of sugarcane in El Salvador, Mexico, and Panama. These findings also confirm the wider distribution of orange rust in the Western Hemisphere. References: (1) E. Chavarria et al. Plant Dis. 93:425, 2009. (2) J. C. Comstock et al. Plant Dis. 92:175, 2008. (3) W. Ovalle et al. Plant Dis. 92:973, 2008.

Cancellations beyond finiteness in N=8 supergravity at three loops.

We construct the three-loop four-point amplitude of N=8 supergravity using the unitarity method. The amplitude is ultraviolet finite in four dimensions. Novel cancellations, not predicted by traditional superspace power-counting arguments, render its degree of divergence in D dimensions no worse than that of N=4 super-Yang-Mills theory--a finite theory in four dimensions. Similar cancellations can be identified at all loop orders in certain unitarity cuts, suggesting that N=8 supergravity may be a perturbatively finite theory of quantum gravity.

Central and peripheral haemodynamic effects of L-NAME infusion in healthy volunteers.

AIMS: To evaluate the effects of the intravenous administration of the nitric oxide synthesis inhibitor N(g)nitro-L-arginine methyl ester (L-NAME) in healthy volunteers. METHODS: L-NAME (0.25, 0.5 and 0.75 mg/kg over 8 min) was infused in 13 healthy male volunteers. Finally, subjects were infused with either L- or D-arginine. RESULTS: L-NAME resulted in dose-dependent falls in heart rate 60 bpm (55-64 bpm) to 49 bpm (46-52 bpm) (P<0.01) and increased mean arterial pressure 77.0 mmHg (73.2-80.8 mmHg) to 90.0 mmHg (87.1-92.8 mmHg) (P<0.01). The cardiac output was significantly reduced after each L-NAME infusion, and systemic vascular resistance increased linearly over the dosage range. Cardiac stroke volume was significantly reduced only following 0.75 mg/kg/min L-NAME: from 100 ml (91.3-108.7 ml) to 83 ml (74.7-91.4 ml); P<0.01. Forearm blood flow was unchanged at any dosage. L-arginine but not D-arginine infusion reversed the haemodynamic effects of L-NAME. CONCLUSIONS: Contrasting with the profound dose-dependent effects of L-NAME had significant effects on central haemodynamics but no discernible effects on peripheral blood flow.

Early vascular abnormalities and de novo nitrate tolerance in diabetes mellitus.

OBJECTIVE: The haemodynamic consequence of altered mechanical wall properties in diabetes can impair the compliance characteristics or pulsatile function of arteries before changes in calibre or peripheral resistance become evident. We studied the sensitivity of pulsatile and steady-state haemodynamic variables in identifying vascular abnormalities and assessing arterial responsiveness to glyceryl trinitrate (GTN) in patients with diabetes, free from clinical complications of the disease. METHODS: Radial artery pressure waveforms were recorded in 22 patients with diabetes and 22 age- and sex-matched control subjects, using a calibrated tonometer device. A computer-based assessment of the diastolic pressure decay was used to quantify changes in arterial waveform morphology in terms of pulsatile (arterial compliance) and steady-state (peripheral resistance) haemodynamics. Pressure pulse waveforms were recorded before and 3, 6 and 9 min after the administration of 300 micro g of GTN. RESULTS: Of the pulsatile and steady-state impedance parameters, only small artery compliance was significantly different in patients, 4.7 ml/mmHg (95% CI 3.8-5.8), compared with control subjects 7.1 ml/mmHg (95% CI 5.4-8.7); (p < 0.05). In response to GTN small artery compliance increased, and systemic vascular resistance decreased significantly in control subjects; (p < 0.05) but remained unchanged in patients with diabetes. CONCLUSIONS: Arterial waveform analysis proved more sensitive in detecting early vascular abnormalities and tracking the haemodynamic effects of GTN in patients with diabetes than changes in total peripheral resistance. The diminished responsiveness of the arterial vasculature to organic nitrates may have therapeutic implications for the treatment of cardiovascular disease in diabetes mellitus.