Metabolomic profiling of wild rooibos (Aspalathus linearis) ecotypes and their antioxidant-derived phytopharmaceutical potential.

INTRODUCTION: Aspalathus linearis (commonly known as rooibos) is endemic to the Cape Floristic Region of South Africa and is a popular herbal drink and skin phytotherapeutic ingredient, with health benefits derived primarily from its unique phenolic content. Several, seemingly habitat-specific ecotypes from the Cederberg (Western Cape) and Northern Cape have morphological, ecological, genetic and biochemical differences. OBJECTIVES AND METHODS: Despite the commercial popularity of the cultivated variety, the uncultivated ecotypes are largely understudied. To address gaps in knowledge about the biochemical constituency, ultra-performance liquid chromatography-mass spectrometry analysis of fifteen populations was performed, enabling high-throughput metabolomic fingerprinting of 50% (v/v) methanolic extracts. Antioxidant screening of selected populations was performed via three assays and antimicrobial activity on two microbial species was assessed. The metabolomic results were corroborated with total phenolic and flavonoid screening of the extracts. RESULTS AND DISCUSSION: Site-specific chemical lineages of rooibos ecotypes were confirmed via multivariate data analyses. Important features identified via PLS-DA disclosed higher relative abundances of certain tentative metabolites (e.g., rutin, aspalathin and apiin) present in the Dobbelaarskop, Blomfontein, Welbedacht and Eselbank sites, in comparison to other locations. Several unknown novel metabolites (e.g., m/z 155.0369, 231.0513, 443.1197, 695.2883) are responsible for metabolomic separation of the populations, four of which showed higher amounts of key metabolites and were thus selected for bioactivity analysis. The Welbedacht and Eselbank site 2 populations consistently displayed higher antioxidant activities, with 2,2-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radical scavenging activities of 679.894 ± 3.427 µmol Trolox/g dry matter and 635.066 ± 5.140 µmol Trolox/g dry matter, respectively, in correlation with a high number of phenolic and flavonoid compounds. The contribution of the individual metabolites to the pharmacological effectiveness of rooibos remains unknown and as such, further structural elucidation and phytopharmacological testing is thus urgently needed.

Does point-of-care ultrasonography improve diagnostic accuracy in emergency department patients with undifferentiated hypotension? An international randomized controlled trial from the SHOC-ED investigators.

PURPOSE: Point-of-care ultrasonography (POCUS) is an established tool in the management of hypotensive patients in the emergency department (ED). We compared the diagnostic accuracy of a POCUS protocol versus standard assessment without POCUS in patients with undifferentiated hypotension. METHODS: This was an international, multicenter randomized controlled trial included three EDs in North America and three in South Africa from September 2012 to December 2016. Hypotensive patients were randomized to early POCUS protocol plus standard care (POCUS group) or standard care without POCUS (control group). Initial and secondary diagnoses were recorded at 0 and 60 min. The main outcome was measures of diagnostic accuracy of a POCUS protocol in differentiating between cardiogenic and non-cardiogenic shock. Secondary outcomes were diagnostic performance for shock sub-types, as well as changes in perceived category of shock and overall diagnosis. RESULTS: Follow-up was completed for 270 of 273 patients. For cardiogenic shock, the POCUS-based diagnostic approach (POCUS) performed similarly to the non-POCUS approach (control) for specificity [95.5% (89.9-98.5) vs.93.8% (87.7-97.5)]; positive likelihood ratio (17.92 vs 14.80); negative likelihood ratio (0.21 vs 0.09) and diagnostic odds ratio (85.6 vs 166.57), with a similar overall diagnostic accuracy between the two approaches [93.7% (88-97.2) vs 93.6% (87.8-97.2)]. Diagnostic performance measures were similar across sub-categories of shock. CONCLUSION: This is the first randomized controlled trial to compare diagnostic performance of a POCUS protocol to standard care without POCUS in undifferentiated hypotensive ED patients. POCUS performed well diagnostically in undifferentiated hypotensive patients, especially as a rule-in test; however, performance did not differ meaningfully from standard assessment.

RéSUMé: OBJECTIF: L'échographie au point d'intervention (POCUS) est un outil bien établi dans la gestion des patients hypotendus dans le service des urgences. Nous avons comparé la précision diagnostique d'un protocole POCUS par rapport à une évaluation standard sans POCUS chez des patients présentant une hypotension indifférenciée. MéTHODES: Il s'agissait d'un essai contrôlé randomisé international multicentrique incluant 3 services d'urgence en Amérique du Nord et 3 en Afrique du Sud de septembre 2012 à décembre 2016. Les patients hypotenseurs ont été répartis par randomisation selon le protocole POCUS précoce plus les soins standard (groupe POCUS) ou les soins standard sans POCUS (groupe témoin). Les diagnostics initiaux et secondaires ont été enregistrés à 0 et 60 minutes. Le principal résultat était la mesure de la précision diagnostique d'un protocole POCUS pour différencier le choc cardiogénique du choc non cardiogénique. Les résultats secondaires étaient la performance diagnostique pour les sous-types de chocs, ainsi que les changements dans la perception de la catégorie de choc et du diagnostic global. RéSULTATS: Le suivi a été complété pour 270 des 273 patients. Pour le choc cardiogénique, l'approche diagnostique basée sur le POCUS (POCUS) a donné des résultats similaires à l'approche non-POCUS (Contrôle) pour la spécificité (95,5 % (89,9­98,5) vs 93,8 % (87,7­97,5)) ; Rapport de vraisemblance positif (17,92 vs 14,80) ; Le rapport de vraisemblance négatif (0,21 vs 0,09) et le rapport de cotes diagnostiques (85,6 vs 166,57), avec une précision diagnostique globale similaire entre les deux approches (93,7 % (88­97,2) vs 93,6 % (87,8­97,2). Les mesures de performance diagnostique étaient similaires dans toutes les sous-catégories de choc. CONCLUSION: Il s'agit du premier essai contrôlé randomisé visant à comparer la performance diagnostique d'un protocole POCUS aux soins standard sans POCUS chez des patients hypotendus indifférenciés aux urgences. La POCUS a donné de bons résultats diagnostiques chez les patients hypotendus indifférenciés, surtout en tant que test de référence ; cependant, les performances ne diffèrent pas de manière significative de l'évaluation standard.

Stevens' Cure (Umckaloabo)-the vindication of a patent medicine.

Stevens' Cure (Umckaloabo) emerged as a patent medicine claiming to treat tuberculosis in the United Kingdom at the beginning of the 20th century. However, due to its identity being shrouded in secrecy, it was never truly accepted by the medical community. It was "rediscovered" in the 1970s and subsequently developed into a very popular and successful phytopharmaceutical for the treatment of upper respiratory tract infections. Whether Stevens' Cure contained the same ingredient(s) as the modern Umckaloabo has not yet been demonstrated. We attempted to elucidate for the first time the identity of the original ingredient by comparative analysis of historical product samples. Three historical samples of Stevens' Cure were compared with Pelargonium sidoides DC. and P. reniforme Curt. root per UPLC-MS analysis. We confirm that the ingredient-P. sidoides DC.-is indeed the same as used in modern phytotherapy. We also attribute the first ethnopharmacological record of P. sidoides DC. being used for the treatment of tuberculosis to C. H. Stevens, the "creator" of Umckaloabo.

A photoswitchable GPCR-based opsin for presynaptic inhibition.

Optical manipulations of genetically defined cell types have generated significant insights into the dynamics of neural circuits. While optogenetic activation has been relatively straightforward, rapid and reversible synaptic inhibition has proven more elusive. Here, we leveraged the natural ability of inhibitory presynaptic GPCRs to suppress synaptic transmission and characterize parapinopsin (PPO) as a GPCR-based opsin for terminal inhibition. PPO is a photoswitchable opsin that couples to Gi/o signaling cascades and is rapidly activated by pulsed blue light, switched off with amber light, and effective for repeated, prolonged, and reversible inhibition. PPO rapidly and reversibly inhibits glutamate, GABA, and dopamine release at presynaptic terminals. Furthermore, PPO alters reward behaviors in a time-locked and reversible manner in vivo. These results demonstrate that PPO fills a significant gap in the neuroscience toolkit for rapid and reversible synaptic inhibition and has broad utility for spatiotemporal control of inhibitory GPCR signaling cascades.

Fatal pyrrolizidine alkaloid poisoning of infants caused by adulterated Senecio coronatus.

Senecio coronatus (known as izonkozonko and ubulibazi in Zulu) is commonly used in traditional medicine in South Africa as purification purgative and enemas for infants during weaning. We show for the first time that this species does not contain pyrrolizidine alkaloids and that reported cases of fatal hepatic sinusoidal obstruction syndrome in infants were caused by wrongly identified Senecio species containing large amounts of retrorsine-N-oxide. A validated ultra performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) method for the detection and quantitation of pyrrolizidine alkaloids is described.

Toward the identification of a phytocannabinoid-like compound in the flowers of a South African medicinal plant (Leonotis leonurus).

OBJECTIVE: Current global trends on natural therapeutics suggest an increasing market interest toward the use and discovery of new plant-derived therapeutic compounds, often referred to as traditional medicine (TM). The Cannabis industry is currently one such focal area receiving attention, owing to the occurrence of phytocannabinoids (pCBs) which have shown promise in health-promotion and disease prevention. However, the occurrence of pCBs in other plant species are often overlooked and rarely studied. Leonotis leonurus (L.) R. Br. is endemic to South Africa with a rich history of use in TM practices amongst indigenous people and, has been recorded to induce mild psychoactive effects akin to Cannabis. While the leaves have been well-reported to contain therapeutic phytochemicals, little information exists on the flowers. Consequently, as part of a larger research venture, we targeted the flowers of L. leonurus for the identification of potential pCB or pCB-like compounds. RESULTS: Flower extracts were separated and analyzed using high performance thin layer chromatography (HPTLC). A single pCB candidate was isolated from HPTLC plates and, using liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS), we could successfully group this compound as a fatty amide and tentatively identified as 7,10,13,16-Docosatetraenoylethanolamine (adrenoyl-EA), a known bioactive compound.

Economic and public health impact of decentralized HIV viral load testing: A modelling study in Kenya.

Kenya has the world's 4th largest HIV burden. Various strategies to control the epidemic have been implemented, including the implementation of viral load (VL) testing to monitor HIV patients on ARVs. Like many resource limited settings, Kenya's healthcare system faces serious challenges in effectively providing quality health services to its population. Increased investments to strengthen the country's capacity to diagnose, monitor and treat diseases, particularly HIV and TB, continue to be made but are still inadequate in the face of global health goals like the UNAIDS 90:90:90 which require scaling up of VL tests amid existing constraints. In Kenya, there is an increase in the demand for VL tests amidst these existing constraints. The GeneXpert system is a diagnostic point-of-care technology that can quantify, amongst others, HIV VL. Currently, GeneXpert technology is widely distributed in Kenya for testing of tuberculosis. This study aimed to determine the economic and public health impact of incorporating VL test modules on the existing GeneXpert infrastructure. Markov models were constructed for different populations (non-pregnant adults, pregnant women and children). The scenarios analysed were 100% centralized VL testing compared to 50% GeneXpert plus 50% centralized VL testing, with time horizons of 5 years for the adult and child populations, and 31 months for the pregnant population. Incremental effectiveness was measured in terms of the number of HIV transmissions or opportunistic infections avoided when implementing the GeneXpert scenario compared to a 100% centralized scenario. The model indicated that, for all three populations combined, the GeneXpert scenario resulted in 117 less HIV transmissions and 393 less opportunistic infections. The cost decreased by $21,978,755 for the non-pregnant and pregnant adults and $22,808,533 for non-pregnant adults, pregnant adults and children. The model showed that GeneXpert would cost less and be more effective in terms of total cost per HIV transmission avoided and the total cost per opportunistic infection avoided, except for the pregnant population, when considered separately.

[Psoriasis migrans : Erythema migrans as Koebner phenomenon in psoriasis]. / Psoriasis migrans : Erythema migrans als Köbner-Phänomen bei Psoriasis.

Psoriasis is a chronic inflammatory disorder of the epidermis, which can be induced by systemic factors, such as streptococci infections or drugs. In addition, psoriasis can be caused by a local cutaneus trauma, known as Koebner phenomenon. Here, we describe a woman with psoriasis in remission, who developed a new psoriatic lesion due to a cutaneous infection with Borrelia burgdorferi. After causal therapy with doxycycline, the erythema migrans and psoriasis lesions disappeared.

A role for genetic susceptibility in sporadic focal segmental glomerulosclerosis.

Focal segmental glomerulosclerosis (FSGS) is a syndrome that involves kidney podocyte dysfunction and causes chronic kidney disease. Multiple factors including chemical toxicity, inflammation, and infection underlie FSGS; however, highly penetrant disease genes have been identified in a small fraction of patients with a family history of FSGS. Variants of apolipoprotein L1 (APOL1) have been linked to FSGS in African Americans with HIV or hypertension, supporting the proposal that genetic factors enhance FSGS susceptibility. Here, we used sequencing to investigate whether genetics plays a role in the majority of FSGS cases that are identified as primary or sporadic FSGS and have no known cause. Given the limited number of biopsy-proven cases with ethnically matched controls, we devised an analytic strategy to identify and rank potential candidate genes and used an animal model for validation. Nine candidate FSGS susceptibility genes were identified in our patient cohort, and three were validated using a high-throughput mouse method that we developed. Specifically, we introduced a podocyte-specific, doxycycline-inducible transactivator into a murine embryonic stem cell line with an FSGS-susceptible genetic background that allows shRNA-mediated targeting of candidate genes in the adult kidney. Our analysis supports a broader role for genetic susceptibility of both sporadic and familial cases of FSGS and provides a tool to rapidly evaluate candidate FSGS-associated genes.

Mutations in the gene that encodes the F-actin binding protein anillin cause FSGS.

FSGS is characterized by segmental scarring of the glomerulus and is a leading cause of kidney failure. Identification of genes causing FSGS has improved our understanding of disease mechanisms and points to defects in the glomerular epithelial cell, the podocyte, as a major factor in disease pathogenesis. Using a combination of genome-wide linkage studies and whole-exome sequencing in a kindred with familial FSGS, we identified a missense mutation R431C in anillin (ANLN), an F-actin binding cell cycle gene, as a cause of FSGS. We screened 250 additional families with FSGS and found another variant, G618C, that segregates with disease in a second family with FSGS. We demonstrate upregulation of anillin in podocytes in kidney biopsy specimens from individuals with FSGS and kidney samples from a murine model of HIV-1-associated nephropathy. Overexpression of R431C mutant ANLN in immortalized human podocytes results in enhanced podocyte motility. The mutant anillin displays reduced binding to the slit diaphragm-associated scaffold protein CD2AP. Knockdown of the ANLN gene in zebrafish morphants caused a loss of glomerular filtration barrier integrity, podocyte foot process effacement, and an edematous phenotype. Collectively, these findings suggest that anillin is important in maintaining the integrity of the podocyte actin cytoskeleton.

Economic appraisal of dabigatran as first-line therapy for stroke prevention in atrial fibrillation.

BACKGROUND: Dabigatran is an oral anticoagulant direct thrombin inhibitor recently registered in South Africa (SA) to reduce the risk of stroke and systemic embolism in patients with atrial fibrillation (AF). Owing to the price disparity between warfarin (the current gold standard for treatment of patients with AF) and dabigatran, we conducted an economic appraisal of the use of dabigatran compared with warfarin from a payer perspective in the South African private healthcare setting. OBJECTIVES: To estimate the cost-effectiveness (CE) and budget impact of dabigatran compared with warfarin for the prevention of stroke in AF patients. Methods. A previously published Markov model was populated with SA cost and mortality data to estimate the CE and budget impact analysis of dabigatran over a lifetime horizon. The model population consisted of a cohort of patients of whom those aged younger than 80 years used dabigatran 150 mg twice daily and those older than 80 years 110 mg twice daily. Modelled outcomes included total cost, quality-adjusted life years (QALYs) and incremental CE ratio (ICER), with the effectiveness measured by QALYs gained. RESULTS: Dabigatran compared with warfarin as first-line treatment was estimated to have an ICER of R93 290 and an average incremental cost per beneficiary per month of R0.39 over a 5-year period. Conservative assumptions were made regarding the number of international normalised ratio monitoring tests for patients on warfarin, and the ICER is estimated to decrease by as much as 15.7% under less stringent assumptions. A robust sensitivity analysis was also performed. CONCLUSION: Dabigatran as first-line treatment compared with warfarin for the use of stroke prevention in patients with AF is deemed cost-effective when used in accordance with its registered indication in the SA private sector.

Assessment of glutathione levels in model solution and grape ferments supplemented with glutathione-enriched inactive dry yeast preparations using a novel UPLC-MS/MS method.

A novel, robust and fast ultra-high performance liquid chromatography-MS method has been developed for the simultaneous quantification of reduced glutathione (GSH) and oxidised glutathione (GSSG) in grape juice, wine and model wine solution. Sample preparation is minimal and does not require derivatisation. The method has very good performance in terms of sensitivity and selectivity. The limit of detection was 0.002 and 0.001 mg L(-1) for GSH and GSSG, respectively. The amount of GSH and GSSG released by commercial glutathione-enriched inactivated dry yeast preparations (GSH-IDYs) into a model solution was assessed. Significant differences in the amount of GSH and/or GSSG released into a model wine by different GSH-IDYs were observed, with ethanol influencing this release under certain conditions. The GSH and GSSG levels in grape juice fermentations supplemented with GSH-IDY were also assessed in relation to different addition times during fermentation. GSH-IDY addition can lead to elevated wine GSH levels, provided the supplementation is done early during alcoholic fermentation.

Resistance in Maize Inbred Lines to Fusarium verticillioides and Fumonisin Accumulation in South Africa.

Fusarium ear rot of maize, caused by Fusarium verticillioides, is an important disease affecting maize production worldwide. Apart from reducing yield and grain quality, F. verticillioides produces fumonisins which have been associated with mycotoxicoses of animals and humans. Currently, no maize breeding lines are known with resistance to F. verticillioides in South Africa. The objective of this study, therefore, was to evaluate 24 genetically diverse maize inbred lines as potential sources of resistance to Fusarium ear rot and fumonisin accumulation in field trials at Potchefstroom and Vaalharts in South Africa. After artificial silk channel inoculation with F. verticillioides, Fusarium ear rot development was determined at harvest and fumonisins B1, B2, and B3 quantified. A significant inbred line by location effect was observed for Fusarium ear rot severity (P ≤ 0.001), although certain lines proved to be consistently resistant across both locations. The individual inbred lines also differed considerably in fumonisin accumulation between Potchefstroom and Vaalharts, with differentiation between susceptible and potentially resistant inbred lines only being possible at Vaalharts. A greenhouse inoculation trial was then also performed on a subset of potentially resistant and highly susceptible lines. The inbred lines CML 390, CML 444, CML 182, VO 617Y-2, and RO 549 W consistently showed a low Fusarium ear rot (<5%) incidence at both Potchefstroom and Vaalharts and in the greenhouse. Two of these inbred lines, CML 390 and CML 444, accumulated fumonisin levels <5 mg kg-1. These lines could potentially act as sources of resistance for use within a maize breeding program.

Arhgap24 inactivates Rac1 in mouse podocytes, and a mutant form is associated with familial focal segmental glomerulosclerosis.

The specialized epithelial cell of the kidney, the podocyte, has a complex actin-based cytoskeleton. Dynamic regulation of this cytoskeleton is required for efficient barrier function of the kidney. Podocytes are a useful cell type to study the control of the actin cytoskeleton in vivo, because disruption of components of the cytoskeleton results in podocyte damage, cell loss, and a prototypic injury response called focal segmental glomerulosclerosis (FSGS). Searching for actin regulatory proteins that are expressed in podocytes, we identified a RhoA-activated Rac1 GTPase-activating protein (Rac1-GAP), Arhgap24, that was upregulated in podocytes as they differentiated, both in vitro and in vivo. Increased levels of active Rac1 and Cdc42 were measured in Arhgap24 knockdown experiments, which influenced podocyte cell shape and membrane dynamics. Consistent with a role for Arhgap24 in normal podocyte functioning in vivo, sequencing of the ARHGAP24 gene in patients with FSGS identified a mutation that impaired its Rac1-GAP activity and was associated with disease in a family with FSGS. Thus, Arhgap24 contributes to the careful balancing of RhoA and Rac1 signaling in podocytes, the disruption of which may lead to kidney disease.

Procedural sedation in the emergency centre.

BACKGROUND: The performance of safe and effective procedural sedation in the emergency centre has become a core competency in emergency medicine internationally. However, in South Africa clear guidelines are lacking and this guideline attempts to set out the standard for the routine safe use of procedural sedation by clinical staff in emergency centres. METHOD: The Emergency Medicine Society of South Africa (EMSSA) appointed a task group to analyse the international literature and guidelines, and a draft document was produced which was revised by consensus input from an expert panel. RESULTS AND CONCLUSION: A simple and clear practice guideline has been developed for health professionals working in emergency centres in South Africa. This guideline will help to improve the provision of emergency procedural sedation, which is an important component of the care provided in emergency centres.

Quantification of melamine absorption, distribution to tissues, and excretion by sheep.

Eight Döhne Merino rams were used to quantify apparent absorption, distribution to tissues, and excretion of dietary melamine in sheep. Two batches of concentrate pellets were made; one (CON) contained corn gluten meal with no detectable melamine and the other (MEL) contained corn gluten meal that was previously found to be highly contaminated with melamine at 15,117 mg/kg. The MEL pellets contained 1,149 mg/kg of melamine. During a 10-d adaptation period, all the animals received a forage-based diet supplemented with 600 g/d of the CON pellets. This was followed by an 8-d collection period during which 6 of the animals received MEL pellets and 2 received CON pellets. Melamine intake of sheep that received MEL pellets was 0.69 g/d. Blood samples were taken before first ingestion of MEL pellets on d 1 and again on d 3, 6, and 8 of the collection period for melamine and serum creatinine analyses. Feces and urine were collected quantitatively over the 8 d for proximate and melamine analyses. All the animals were slaughtered at the end of the trial, and samples of the LM, liver, kidneys, and abdominal fat were taken for melamine analysis. Data of the 2 sheep that received CON pellets for the duration of the trial confirmed that no melamine was detected in any of the samples, and no statistical analyses were performed on these data. The apparent digestibility or efficiency of absorption of ingested melamine was 76.7%. Melamine was detected in the urine, blood, muscle (LM), and fat tissue of all the sheep that received MEL pellets. Serum melamine concentrations reached 5.4 mg/kg on d 8 of the collection period, and the meat (LM) contained 9.6 mg/kg of melamine. Calculations on the partitioning of ingested melamine suggested that urine is the major excretion route accounting for 53.2%, whereas feces accounted for 23.3% of ingested melamine. Approximately 3.5% of the ingested melamine was detected in muscle. It was concluded that ingested melamine is highly absorbable from the small intestine and that a pathway exists for the distribution of dietary melamine to meat.

Hot topic: pathway confirmed for the transmission of melamine from feed to cow's milk.

Eight lactating Holstein cows were randomly allotted to 2 groups in a trial to establish whether a pathway exists for the transmission of melamine from feed to milk. All cows received oat hay ad libitum and 15 kg of concentrate pellets per cow daily. The concentrate pellets contained either melamine-contaminated corn gluten meal of Chinese origin (melamine treatment) or locally produced melamine-free corn gluten meal (control treatment). Cows in the melamine treatment ingested 17.1 g of melamine per day. Cows were milked twice daily, and milk samples were taken once daily during the afternoon milking for melamine and milk component analyses. Melamine appeared in the milk within 8 h after first ingestion of the melamine containing pellets. Melamine concentration reached a maximum of 15.7 mg/kg within 56 h after first ingestion, with an excretion efficiency of approximately 2%. Milk solids and milk urea nitrogen were not affected by treatment. The melamine concentration dropped rapidly after changing all cows back to the control pellets, but melamine only declined to undetectable levels in the milk more than 6 d (152 h) after last ingestion of melamine. Results from the current trial are important to the feed and dairy industries because, until now, any melamine found in milk and milk products was attributed only to the deliberate external addition of melamine to these products, not to adulterated ingredients in animal feeds.

Evidence for susceptibility determinant(s) to psoriasis vulgaris in or near PTPN22 in German patients.

INTRODUCTION: Variant R620W of protein tyrosine phosphatase non-receptor type 22 (PTPN22) has consistently been reported as a susceptibility factor for several autoimmune diseases. We investigated its role in susceptibility to psoriasis, the relevance of possibly other disease-causing variants, and interdependency of the major risk factor for psoriasis at PSORS1. METHODS: R620W was tested in a case-control study initially with 375 German patients and then with an enlarged sample of an additional 418 patients. Analyses were extended to linkage disequilibrium (LD) based haplotypes. Potential interaction between risk haplotypes of PTPN22 and the PSORS1 associated risk allele was tested by regression analysis. PTPN22 coding sequence was determined in 20 patients carrying the risk haplotype. Association and regression analysis were also performed in the extended case-control study. RESULTS: R620W was not associated in either case-control study, while significant association (corrected for multiple testing) with one haplotype (C-4) of the LD block encompassing PTPN22 as well with another haplotype (B-3) within an adjacent telomeric LD block was detected. No evidence for interaction between risk haplotype C-4 and the PSORS1 associated risk allele was found. Sequencing excluded other coding variants within PTPN22 as a basis for association findings. Analysis of the extended study group confirmed association for haplotypes B-3 and C-4 and independence of risk haplotypes C-4 and PSORS1. DISCUSSION: We exclude a major role of *620W in German psoriasis patients but suggest that other susceptibility determinant(s) within non-coding regions of PTPN22 or its proximity might exist acting independently of the major PSORS1 risk factor.