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Retinal dystrophies (RDs) are hereditary blinding eye conditions that are highly variable in their clinical presentation. The remarkable genetic heterogeneity that characterizes RD was a major challenge in establishing the molecular diagnosis in these patients until the recent advent of next‐generation sequencing. It remains unclear, however, what percentage of autosomal recessive RD remain undiagnosed when all established RD genes are sequenced. We enrolled 75 families in which RD segregates in an apparently autosomal recessive manner. We show that the yield of a multigene panel that contains known RD genes is 67.5%. The higher yield (82.3%) when whole exome sequencing was implemented instead was often due to hits in genes that were not included in the original design of the panel. We also show the value of homozygosity mapping even during the era of exome sequencing in uncovering cryptic mutations. In total, we describe 45 unique likely deleterious variants (of which 18 are novel including one deep intronic and one genomic deletion mutation). Our study suggests that the genetic heterogeneity of autosomal recessive RD is approaching saturation and that any new RD genes will probably account for only a minor role in the mutation burden. [ABSTRACT FROM AUTHOR]

Microphthalmia is a developmental eye defect that is highly variable in severity and in its potential for systemic association. Despite the discovery of many disease genes in microphthalmia, at least 50% of patients remain undiagnosed genetically. Here, we describe a cohort of 147 patients (93 families) from our highly consanguineous population with various forms of microphthalmia (including the distinct entity of posterior microphthalmos) that were investigated using a next‐generation sequencing multi‐gene panel (i‐panel) as well as whole exome sequencing and molecular karyotyping. A potentially causal mutation was identified in the majority of the cohort with microphthalmia (61%) and posterior microphthalmos (82%). The identified mutations (55 point mutations, 15 of which are novel) spanned 24 known disease genes, some of which have not or only very rarely been linked to microphthalmia (PAX6, SLC18A2, DSC3 and CNKSR1). Our study has also identified interesting candidate variants in 2 genes that have not been linked to human diseases (MYO10 and ZNF219), which we present here as novel candidates for microphthalmia. In addition to revealing novel phenotypic aspects of microphthalmia, this study expands its allelic and locus heterogeneity and highlights the need for expanded testing of patients with this condition. [ABSTRACT FROM AUTHOR]

Dominant SCN1B mutations are known to cause several epilepsy syndromes in humans. Only 2 epilepsy patients to date have been reported to have recessive mutations in SCN1B as the likely cause of their phenotype. Here, we confirm the recessive inheritance of 2 novel SCN1B mutations in 5 children from 3 families with developmental epileptic encephalopathy. The recessive inheritance and early death in these patients is consistent with the Dravet-like phenotype observed in Scn1b−/− mice. The 'negative' clinical exome in one of these families highlights the need to consider recessive mutations in the interpretation of variants in typically dominant genes. [ABSTRACT FROM AUTHOR]

Background Breath testing is becoming an important diagnostic method to evaluate many disease states. In the light of rising healthcare costs, is important to develop a simple non-invasive tool to potentially identify paediatric patients who need endoscopy for suspected inflammatory bowel disease (IBD). Aim To analyse exhaled volatile organic compounds (VOCs) and investigate the presence of a unique breath patterns to differentiate paediatric patients with (IBD) from healthy controls. Methods A cross-sectional, single-centre study included paediatric IBD patients and healthy controls (age range, 5-21 years). The diagnosis of IBD was confirmed by endoscopic, histological and radiographic data. Exhaled breath was collected and analysed using a selective ion flow tube mass spectroscopy (SIFT-MS) to identify new markers or patterns of IBD. Results One hundred and seventeen patients (62 with IBD and 55 healthy controls) were included in the study. Linear discriminant analysis and principle component analysis of mass scanning ion peak data demonstrated 21 pre-selected VOCs correctly classify patients with IBD or as healthy controls; P < 0.0001. Multivariable logistic regression analysis further showed three specific VOCs (1-octene, 1-decene, (E)-2-nonene) had excellent accuracy for predicting the presence of IBD with an area under the curve (AUC) of 0.96 (95% CI: 0.93-0.99). No significant difference in VOCs was found between patients with Crohn's disease or ulcerative colitis, and no significant correlation was seen with disease activity. Conclusion These pilot data support the hypothesis that a unique breathprint potentially exists for paediatric IBD in the exhaled metabolome. [ABSTRACT FROM AUTHOR]

Background Ectopic fat deposition in the pancreas and its association with hepatic steatosis have not previously been examined in patients with biopsy-proven non-alcoholic fatty liver disease ( NAFLD). Aim To quantify pancreatic fat using a novel magnetic resonance imaging ( MRI) technique and determine whether it is associated with hepatic steatosis and/or fibrosis in patients with NAFLD. Methods This is a cross-sectional study including 43 adult patients with biopsy-proven NAFLD who underwent clinical evaluation, biochemical testing and MRI. The liver biopsy assessment was performed using the NASH- CRN histological scoring system, and liver and pancreas fat quantification was performed using a novel, validated MRI biomarker; the proton density fat fraction. Results The average MRI-determined pancreatic fat in patients with NAFLD was 8.5% and did not vary significantly between head, body, and tail of the pancreas. MRI-determined pancreatic fat content increased significantly with increasing histology-determined hepatic steatosis grade; 4.6% in grade 1; 7.7% in grade 2; 13.0% in grade 3 ( P = 0.004) respectively. Pancreatic fat content was lower in patients with histology-determined liver fibrosis than in those without fibrosis (11.2% in stage 0 fibrosis vs. 5.8% in stage 1-2 fibrosis, and 6.9% in stage 3-4 fibrosis, P = 0.013). Pancreatic fat did not correlate with age, body mass index or diabetes status. Conclusions In patients with NAFLD, increased pancreatic fat is associated with hepatic steatosis. However, liver fibrosis is inversely associated with pancreatic fat content. Further studies are needed to determine underlying mechanisms to understand if pancreatic steatosis affects progression of NAFLD. [ABSTRACT FROM AUTHOR]

The article presents the study on the use of two-dimensional (2D) ultrasound enhanced with the three-dimensional (3D) reverse-face view on detecting lip, alveolar ridge, and hard palate abnormalities. It states that cleft lip or palate is a non-lethal congenital abnormality that result from the failure of fusion of facial processes. It says that ultrasound can achieve prenatal detection of orofacial clefting. It adds that 2D and 3D imaging can be used on the assessment of facial clefts.

Aliment Pharmacol Ther 31, 640–647 Background The thiopurine drugs, azathioprine and mercaptopurine (MP), are established treatments for IBD. However, therapeutic failure caused by adverse drug reactions occurs frequently. Aim To study combination of allopurinol with reduced-dose thiopurine in an attempt to avoid adverse drug reactions in the treatment of IBD. Methods Patients with drug reactions to full-dose thiopurines were recruited for combination therapy in two IBD centres in this retrospective study. Dosing was guided by measuring thiopurine methyltransferase (for UK patients) or thioguanine nucleotides and methyl-6MP (Australian patients). Response was monitored by clinical activity indices. Results Of 41 patients, 25 had non-hepatic and 16 had hepatitic reactions. Clinical remission was achieved in 32 patients (78%) with a median follow-up of 41 weeks (range 0.5–400). Patients who did not respond to combination therapy tended to fail early with the same adverse reaction. The relative risk of having an adverse reaction with methyl-6MP in the top interquartile range was 2.7 (1.3–28) times that with methyl-6MP in the lower three quartiles (95% confidence interval). Conclusion The combined experience from our centres is the largest reported experience of this combination therapy strategy in IBD, and the first to provide evidence for benefit in thiopurine and allopurinol co-therapy to avoid non-hepatitic adverse drug reactions. [ABSTRACT FROM AUTHOR]

Background. Angiogenesis studies are limited by the clinical relevance of laboratory model systems. We developed a new method for measuring dead microvascular (MV) cells in clinical tissue, fluid and blood specimens, and applied this system to make several potentially novel observations relating to cancer pharmacology. Methods. Dead MV cells tend to have a hyperchromatic, refractile quality, further enhanced during the process of staining with Fast Green and counterstaining with either haematoxylin–eosin or Wright–Giemsa. We used this system to quantify the relative degree of direct antitumour versus anti-MV effects of cisplatin, erlotinib, imatinib, sorafenib, sunitinib, gefitinib and bevacizumab. Results. Bevacizumab had striking anti-MV effects and minimal antitumour effects; cisplatin had striking antitumour effects and minimal anti-MV effects. The `nib' drugs had mixed antitumour and anti-MV effects. Anti-MV effects of erlotinib and gefitinib were equal to those of sunitinib and sorafenib. There was no detectable VEGF in culture medium without cells; tumour cells secreted copious VEGF, reduced to undetectable levels by bevacizumab, greatly reduced by cytotoxic levels of cisplatin + anguidine, and variably reduced by DMSO and/or ethanol. We observed anti-MV additivity between bevacizumab and other drugs on an individual patient basis. Peripheral blood specimens had numerous MV cells which were strikingly visualized for quantification with public domain image analysis software using bevacizumab essentially as an imaging reagent. Conclusions. This system could be adapted for simple, inexpensive and sensitive/specific detection of tissue and circulating MV cells in a variety of neoplastic and non-neoplastic conditions, and for drug development and individualized cancer treatment. [ABSTRACT FROM AUTHOR]

Aims Since relatively little is known about the pharmacokinetics of 6-thioguanine (6TG) in children receiving 6-thioguanine for maintenance therapy of acute lymphoblastic leukaemia (ALL), we studied plasma drug concentrations under standardized conditions and investigated the effect of food on parent drug pharmacokinetics and the accumulation of the active metabolites 6-thioguanine nucleotides (6-TGNs) in red cells. Methods Single oral doses of 40 mg of 6-TG were administered both in the fasting and fed state to children with ALL. Pharmacokinetic sampling was performed up to 6 h post dose. Daily oral doses of 40 mg m-2 of 6-TG were administered both fasting and after food over two 4 week periods. Twice weekly samples were taken for metabolite concentrations. The study design was cross-over with each child receiving dosing in either fasted or after food over a 4 week period in each phase. Results Eleven patients were studied. A wide interindividual variation in Cmax (median 313 pmol ml-1, range 51–737) and AUC (median 586 pmol ml-1 h, range 156–1306) was observed in the fasted state. Concomitant food administration resulted in a significant reduction in Cmax (median 71 vs 313 pmol ml-1, P = 0.006, CI from 36 to 426), AUC (median 200 vs 586 pmol ml-1 h, P = 0.006, 95% CI from 109 to 692), and time to reach Cmax (median 1.5 vs 3 h, P = 0.013, 95% CI from 0.74 to 2.73). There was no difference in the steady state concentration of red cell 6-TGNs observed after a 4 week period of 6-TG administered fasting or after food. Conclusions Children with ALL demonstrate significant interindividual variation in 6-TG pharmacokinetics. Although there would appear to be a reduction in parent drug Cmax and AUC with food there was no difference in 6-TGN concentrations after 4 weeks of 6-TG. Taking the drug on an empty stomach may not be necessary. [ABSTRACT FROM AUTHOR]

The macrophage natural resistance gene. Lab, regulates the ability of a selective population of tissue macrophages to control intracellular multiplication of Leishmania donovani by a T-cell independent mechanism. We show here, using mice congenic for Lsh, that this gene also contributes to the acquisition of T-cell-mediated immunity. Whereas both resistant and susceptible mice generate equivalent primary Tall responses to infection, resistant mice show a rapid increase in accessory cell activity, allowing for greater subsequent Tall expansion. This change in accessory cell function correlates with increased class II antigen expression relative to susceptible mice, both in vino during early infection and in vitro in response to induction by interferon-gamma (IFN-γ). Differences in vitro were independent of, but differentially affected by, amastigote infection. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented on clinical spectrum and allelic heterogeneity in van den Ende-Gupta syndrome.

The potential of single date fully Polarimetric RADARSAT‐2 data in retrieving crop biophysical parameters using Machine Learning techniques was investigated. Various polarimetric parameters along with coherent and incoherent decomposition techniques were assessed for its sensitivity toward crop parameters like Wet and Dry Biomass, Crop Height, Leaf Area Index and Vegetation Water Content. A set of 39 polarimetric observables extracted from the Quad‐Pol data were used for regression analysis. In this study two Machine Learning techniques Random Forest Regression (RFR) and Multiple Linear Regression (MLR) models were assessed for the prediction of Wet Biomass (gm−2) and Height (cm). The most significant (6 out of 39) variables were applied for prediction. The results revealed that RFR algorithm performed better than MLR. The coefficient of determination (R2) and root‐mean‐square‐error of estimating wet biomass and height were 0.646, 655.65 (gm−2) and 0.71, 14.5 (cm) respectively in RFR and 0.566, 683.86 (gm−2) and 0.65, 16.14 (cm) respectively in MLR. Thus this study explored the effective application of quad‐pol data for assessing sensitivity and accurate retrieval of parameters using optimum PolSAR observables. Key Points: Important polarimetric observables and their sensitivity toward biophysical parameters were analyzedEffective retrieval of crop parameters from a single‐date polarimetric data using Random Forest and Multiple Linear Regression was explored [ABSTRACT FROM AUTHOR]

A response from the authors of the article "Association between novel MRI-estimated pancreatic fat and liver histology-determined steatosis and fibrosis in non-alcoholic fatty liver disease" in the 2013 issue is presented.

A letter to the editor is presented in response to the article "Focal absence of diffusion tensor tracts from primary motor cortex in primary lateral sclerosis" is presented.

We present a case of an intrapartum splenic artery aneurysm (SAA) rupture in a nulliparous woman. EP16.18: Intrapartum splenic artery aneurysm rupture with maternal and fetal survival: a case promptly diagnosed with the aid of hand-held ultrasound There are only 6 cases of intrapartum rupture and 31(of 115) cases of antenatal SAA rupture where both mother and baby survived within the literature. [Extracted from the article]

The carbohydrate‐binding molecule galectin‐3 has garnered significant attention recently as a biomarker for various conditions ranging from cardiac disease to obesity. Although there have been several recent studies investigating its role in stroke and other cerebrovascular diseases, awareness of this emerging biomarker in the wider neurology community is limited. We performed a systematic search in PubMed, Embase, Scopus, CINAHL, Clinicaltrials.gov and the Cochrane library in November and December 2016 for articles related to galectin‐3 and cerebrovascular disease. We included both human and pre‐clinical studies in order to provide a comprehensive view of the state of the literature on this topic. The majority of the relevant literature focuses on stroke, cerebral ischemia and atherosclerosis, but some recent attention has also been devoted to intracranial and subarachnoid hemorrhage. Higher blood levels of galectin‐3 correlate with worse outcomes in atherosclerotic disease as well as in intracranial and subarachnoid hemorrhage in human studies. However, experimental evidence supporting the role of galectin‐3 in these phenotypes is not as robust. It is likely that the role of galectin‐3 in the inflammatory cascade within the central nervous system following injury is responsible for many of its effects, but its varied physiological functions and multiple sites of expression mean that it may have different effects depending on the nature of the disease condition and the time since injury. In summary, experimental and human research raises the possibility that galectin‐3, which is closely linked to the inflammatory cascade, could be of value as a prognostic marker and therapeutic target in cerebrovascular disease. [ABSTRACT FROM AUTHOR]

We have previously shown that activation of muscle receptors by passive stretch (PS) increases heart rate (HR) with little change in blood pressure (BP). We proposed that PS selectively inhibits cardiac vagal activity. We attempted to test this by performing PS during experimental alterations in vagal tone. Large decreases in vagal tone were induced using either glycopyrrolate or mild rhythmic exercise. Milder alterations in vagal tone were achieved by altering carotid baroreceptor input: neck pressure (NP) or neck suction (NS). PS of the triceps surae was tested in 14 healthy human volunteers. BP, ECG and respiration were recorded. PS alone caused a significant decrease ( P < 0.05) in R–R interval (962 ± 76 ms at baseline compared to 846 ± 151 ms with PS), and showed a reduction in HR variability, which was not significant. The decrease in R–R interval with PS was significantly less ( P < 0.05, n= 3) following administration of glycopyrrolate (−8.1 ± 4.5 ms) compared to PS alone (−54 ± 11 ms), and also with PS during handgrip (+10 ± 10 ms) compared with PS alone (−74 ± 15 ms) ( P < 0.05, n= 5). Milder reductions in vagal activity (NP) resulted in a small but insignificant further decrease in R–R interval in response to PS (−107 ± 17 ms compared to PS alone −96 ± 13 ms, n= 5). Mild increases in vagal activity (NS) during PS resulted in smaller decreases in R–R interval (−39 ± 5.5 ms) compared to PS alone (−86 ± 17 ms) ( P < 0.05, n= 8). BP was not significantly changed by stretch in any tests. The results indicate that amongst muscle receptors there is a specific group activated by stretch that selectively inhibit cardiac vagal tone to produce tachycardia. [ABSTRACT FROM AUTHOR]

Background Brain change can occur in primary biliary cholangitis ( PBC), potentially as a result of cholestatic and/or inflammatory processes. This change is linked to systemic symptoms of fatigue and cognitive impairment. Aim To identify whether brain change occurs early in PBC. If the change develops early and is progressive, it may explain the difficulty in treating these symptoms. Methods Early disease brain change was explored in 13 patients with newly diagnosed biopsy-proven precirrhotic PBC using magnetisation transfer, diffusion-weighted imaging and 1H magnetic resonance spectroscopy. Results were compared to 17 healthy volunteers. Results Cerebral magnetisation transfer ratios were reduced in early PBC, compared to healthy volunteers, in the thalamus, putamen and head of caudate with no greater reduction in patients with greater symptom severity. Mean apparent diffusion coefficients were increased in the thalamus only. No 1H magnetic resonance spectroscopy abnormalities were seen. Serum manganese levels were elevated in all PBC patients, but no relationship was seen with imaging or symptom parameters. There were no correlations between neuroimaging data, laboratory data, symptom severity scores or age. Conclusions This is the first study to be performed in this precirrhotic patient population, and we have highlighted that neuroimaging changes are present at a much earlier stage than previously demonstrated. The neuroimaging abnormalities suggest that the brain changes seen in PBC occur early in the pathological process, even before significant liver damage has occurred. If such changes are linked to symptom pathogenesis, this could have important implications for the timing of second-line-therapy use. [ABSTRACT FROM AUTHOR]

Bruchfeld A, Goldstein RS, Chavan S, Patel NB, Rosas-Ballina M, Kohn N, Qureshi AR, Tracey KJ. (Karolinska Institute, Stockholm, Sweden; The Feinstein Institute for Medical Research, North Shore University Hospital-LIJ Health System, Manhasset, NY, USA; and Karolinska Institute, Stockholm, Sweden) Whole blood cytokine attenuation by cholinergic agonists ex vivo and relationship to vagus nerve activity in rheumatoid arthritis. J Intern Med 2010; 268:94–101. Objective. The central nervous system regulates innate immunity in part via the cholinergic anti-inflammatory pathway, a neural circuit that transmits signals in the vagus nerve that suppress pro-inflammatory cytokine production by an α-7 nicotinic acetylcholine receptors (α7nAChR) dependent mechanism. Vagus nerve activity is significantly suppressed in patients with autoimmune diseases, including rheumatoid arthritis (RA). It has been suggested that stimulating the cholinergic anti-inflammatory pathway may be beneficial to patients, but it remains theoretically possible that chronic deficiencies in this pathway will render these approaches ineffective. Methods. Here we addressed the hypothesis that inflammatory cells from RA patients can respond to cholinergic agonists with reduced cytokine production in the setting of reduced vagus nerve activity. Results. Measurement of RR interval variability (heart rate variability, HRV), in RA patients ( n = 13) and healthy controls ( n = 10) revealed that vagus nerve activity was significantly depressed in patients. Whole blood cultures stimulated by exposure to endotoxin produced significantly less tumour necrosis factor in samples from RA patients as compared to healthy controls. Addition of cholinergic agonists (nicotine and GTS-21) to the stimulated whole blood cultures however significantly suppressed cytokine production to a similar extent in patients and healthy controls. Conclusion. These findings suggest that it is possible to pharmacologically target the α7nAChR dependent control of cytokine release in RA patients with suppressed vagus nerve activity. As α7nAChR agonists ameliorate the clinical course of collagen induced arthritis in animals, it may be possible in the future to explore whether α7nAChR agonists can improve clinical activity in RA patients. [ABSTRACT FROM AUTHOR]

Background and purpose:M1 muscarinic ACh receptors (mAChRs) represent an attractive drug target for the treatment of cognitive deficits associated with diseases such as Alzheimer's disease and schizophrenia. However, the discovery of subtype-selective mAChR agonists has been hampered by the high degree of conservation of the orthosteric ACh-binding site among mAChR subtypes. The advent of functional screening assays has enabled the identification of agonists such as AC-42 (4-n-butyl-1-[4-(2-methylphenyl)-4-oxo-1-butyl]-piperidine), which bind to an allosteric site and selectively activate the M1 mAChR subtype. However, studies with this compound have been limited to recombinantly expressed mAChRs.Experimental approach:In this study, we have compared the pharmacological profile of AC-42 and a close structural analogue, 77-LH-28-1 (1-[3-(4-butyl-1-piperidinyl)propyl]-3,4-dihydro-2(1H)-quinolinone) at human recombinant, and rat native, mAChRs by calcium mobilization, inositol phosphate accumulation and both in vitro and in vivo electrophysiology.Key results:Calcium mobilization and inositol phosphate accumulation assays revealed that both AC-42 and 77-LH-28-1 display high selectivity to activate the M1 mAChR over other mAChR subtypes. Furthermore, 77-LH-28-1, but not AC-42, acted as an agonist at rat hippocampal M1 receptors, as demonstrated by its ability to increase cell firing and initiate gamma frequency network oscillations. Finally, 77-LH-28-1 stimulated cell firing in the rat hippocampus in vivo following subcutaneous administration.Conclusions and implications:These data suggest that 77-LH-28-1 is a potent, selective, bioavailable and brain-penetrant agonist at the M1 mAChR and therefore that it represents a better tool than AC-42, with which to study the pharmacology of the M1 mAChR.British Journal of Pharmacology (2008) 154, 1104–1115; doi:10.1038/bjp.2008.152; published online 5 May 2008 [ABSTRACT FROM AUTHOR]

Background: Oxytocics are routinely used in an attempt to prevent excessive blood loss during cesarean section. Misoprostol, a potent uterotonic agent, has been reported to be useful in the prevention and treatment of postpartum hemorrhage by several investigators but its use during cesarean section has not been described. The objective of this study was to randomly compare the effectiveness of oral misoprostol with intravenous syntocinon on blood loss during elective cesarean sections under regional anesthesia.Methods: Sixty pregnant women were randomized either to receive misoprostol 400 micrograms orally or syntocinon 10 IU intravenously during cesarean section. The primary outcome measure was intra-operative blood loss as estimated by physicians, and by values of preoperative and postoperative hemoglobin concentration and hematocrit. Demographic characteristics of the subjects and outcomes were compared using chi-square test for categorical and two-sample t-test for continuous data.Results: Baseline characteristics in terms of age, body weight, parity, gestational age and indications for cesarean section were similar in both groups. The estimated blood loss was 545 ml (CI 476-614) in misoprostol group and 533 ml (CI 427-639) in syntocinon group (p = 0.85). Differences in preoperative and postoperative hemoglobin and hematocrit values were also similar in both groups. Two women in the misoprostol group and three in the syntocinon group (p=0.64) required additional oxytocics. One patient in each group required blood transfusion. No serious side effects were noted in either group.Conclusion: Oral misoprostol appears to be safe and as effective as intravenous syntocinon in reduction of intra-operative blood loss during elective cesarean section under regional anesthesia and merits further investigation. [ABSTRACT FROM AUTHOR]

Introduction The incidence of secondary nonresponders is of key concern to physicians treating cervical dystonia with botulinum toxins. The presence of impurities and aggregation of therapeutic proteins are two well-known phenomena that can enhance the immune response. The purity and integrity of Elan's botulinum toxin type B solution (NeuroBloc™) were assessed. Methods Biochemical evaluation of several lots of the type B toxin complex were designed to assess key product attributes, including: (1) specific activity: ratio of potency (mouse IP LD[sub 50] assay) to protein concentration; (2) complex consistency: size exclusion chromatography (SEC), sodium dodecylsulfate polyacrylamide gel electrophoresis (SDS-PAGE), and N-terminal sequencing; and (3) percent nicking: (endoproteolytic activation). Results Specific activity, a sensitive measurement of the purity and activity of the neurotoxin complex, was elevated and consistent (100 U/ng) across all batches. An intact, non-aggregated, non-dissociated toxin complex was demonstrated by size exclusion chromatography with an estimated molecular weight of approximately 700 kilodaltons (kDa). SDS-PAGE analyses confirmed the relative composition and purity of the polypeptides forming the neurotoxin complex. Protein sequencing confirmed the amino acid identity of the eight polypeptides that compose the neurotoxin complex and the site of nicking (between residues 440 and 441). In addition, the percent nicking was highly reproducible (approximately 75% nicked product). Conclusion Elan's botulinum toxin type B (NeuroBloc™) has excellent and reproducible complex integrity and purity profile. It is therefore anticipated that therapeutic use of NeuroBloc™ will minimize the development of neutralizing antibodies and the incidence of secondary non-responders among patients. [ABSTRACT FROM AUTHOR]