SMRT Sequencing Enables High-Throughput Identification of Novel AAVs from Capsid Shuffling and Directed Evolution.

The use of AAV capsid libraries coupled with various selection strategies has proven to be a remarkable approach for generating novel AAVs with enhanced and desired features. The inability to reliably sequence the complete capsid gene in a high-throughput manner has been the bottleneck of capsid engineering. As a result, many library strategies are confined to localized and modest alterations in the capsid, such as peptide insertions or single variable region (VR) alterations. The caveat of short reads by means of next-generation sequencing (NGS) hinders the diversity of capsid library construction, shifting the field away from whole-capsid modifications. We generated AAV capsid shuffled libraries of naturally occurring AAVs and applied directed evolution in both mice and non-human primates (NHPs), with the goal of yielding AAVs that are compatible across both species for translational applications. We recovered DNA from the tissues of injected animal and used single molecule real-time (SMRT) sequencing to identify variants enriched in the central nervous system (CNS). We provide insights and considerations for variant identification by comparing bulk tissue sequencing to that of isolated nuclei. Our work highlights the potential advantages of whole-capsid engineering, as well as indispensable methodological improvements for the analysis of recovered capsids, including the nuclei-enrichment step and SMRT sequencing.

Pylephlebitis due to perforated diverticulitis.

Pylephlebitis or septic thrombophlebitis of the portal vein is an uncommon and frequently fatal complication of diverticulitis. We describe a case report of a patient with pylephlebitis due to a perforation of the sigmoid. The patient was successfully treated with broad spectrum antibiotics and a Hartmann procedure.

GIST (gastro-intestinal stromal tumour) of the gallbladder: a case report.

The authors report a case of a gastrointestinal stromal tumour (GIST) of the gallbladder. GISTs are rare mesenchymal tumours of the gastrointestinal tract, mesentery and omentum. GISTs are characterized by the expression of the KIT protein, a transmembrane tyrosine kinase receptor for stem-cell factor. Only a few GISTs of the gallbladder have been described in the literature. The behaviour of these tumours is not fully understood but long-term survival is rare. Initial treatment consists of aggressive surgery. Radiotherapy and conventional chemotherapy have been mostly unsuccessful. More recently promising studies have been performed with Imatinib, an orally administered tyrosine kinase inhibitor, in patients with advanced disease.

Malingered neurocognitive dysfunction in neurotoxic exposure: an application of the Slick criteria.

Toxic torts are increasing across the country and often the results of the neuropsychological evaluation are crucial for defining damages. Therefore, the accurate differentiation of those damaged by toxic exposure from those exaggerating or fabricating deficits is important. However, there is little research on malingering in this context. Presented are four patients claiming cognitive deficits after apparent occupational neurotoxic exposure who were diagnosed as malingering using the Slick, Sherman, and Iverson criteria. The goals of this article were to (1) illustrate the application of the Slick Criteria; (2) discuss current knowledge about the neurological and neurocognitive effects of toxic substances and its impact on clinical decision-making; (3) discuss the application of the Slick Criteria, specifically, and malingering research, generally, to toxic exposure cases; and (4) propose a paradigm in which medical, toxicological and neuropsychology professionals coordinately evaluate cases of alleged neurotoxic chemical exposure.

Evaluation of suspected stress fractures.

Stress fractures can occur if normal bone is exposed to repeated abnormal stress (fatigue fractures) or if normal stress is placed on bones with compromised elastic resistance (insufficiency fractures). This article describes two patients without a history of excessive stressful activity or apparent metabolic bone disease who developed bilateral distal tibial stress fractures. Different etiologies, clinical presentation, differential diagnosis, and diagnostic imaging modalities of stress fractures are discussed.

Patient satisfaction and symptom relief after anal dilatation.

Anal dilatation is used as a simple method of treatment and has been used for both anal fissure and haemorrhoids. This study examined longer-term results among a cohort of 162 patients, 132 of whom responded to a detailed questionnaire, an 82% response (66 patients were male; age range 17-75 years, median 42 years). Follow-up ranged from 16 months to 36 months (median 27 months) after anal dilatation (68 patients for fissure, 32 for haemorrhoids, and 32 for both). In the early months after dilatation, 83% had symptomatic improvement and 76% remained improved. Five (7%) patients with fissure and 11 with haemorrhoids (17%) required further hospital treatment, while 10% and 17%, respectively, had received further treatment from their general practitioners (GPs). Seventy-one percent said they would have a further anal dilation if symptoms recurred. There was no difference in results obtained by surgeons of different seniority. Complications--bleeding (29%) and difficulty controlling flatus (15%) or faeces (8%)--resolved in all cases. The results of anal dilatation for fissure are generally satisfactory in the longer term, with a trend toward better symptom relief in patients with fissure compared with those with haemorrhoids. We do not recommend anal dilatation as the sole treatment of patients with haemorrhoids, but it may be a useful adjunct to other treatments such as banding or sclerotherapy. Morbidity was generally acceptable and the majority of our patients would be prepared to have this procedure again if their symptoms were to return.

Five-year audit of the acute complications of diverticular disease.

BACKGROUND: The objective of this study was to audit the presentation and outcome for patients admitted with an acute complication of diverticular disease. METHODS: This study was a retrospective review of 418 admissions with an acute complication of diverticular disease over a 5-year interval. RESULTS: Of the 418 admissions, 15 patients were eventually found to have an alternative diagnosis. Some 403 patients were studied further. The overall mortality rate in this group was 5.7 per cent. A total of 113 patients (28.0 per cent) required an operation and in this group the mortality rate was 17.7 per cent. All deaths occurred in patients who had surgery for septic complications or bowel obstruction. Of the patients who had surgery, 90.2 per cent had a resection of the involved colon. One-third of these had a primary anastomosis; the remainder underwent Hartmann's procedure. Some 83 patients had a stoma fashioned and of these 72 went on to have the stoma closed. The median age of those who died after operation was 80 years. An American Society of Anesthesiologists (ASA) score of 3 or more, concurrent medical disease and shock on admission were all associated with a high mortality rate (P < 0.001). Some 30 per cent of patients were readmitted during this study with a further complication of diverticular disease. CONCLUSION: The mortality rate after surgery for acute diverticular disease remains excessive and a high-risk group can be identified before operation. A policy of resection and anastomosis appears justified for selected patients. Adopting a practice of interval elective sigmoid colectomy after admission with acute diverticulitis might prevent readmission with further complications.