A User's Guide to Golden Gate Cloning Methods and Standards.

The continual demand for specialized molecular cloning techniques that suit a broad range of applications has driven the development of many different cloning strategies. One method that has gained significant traction is Golden Gate assembly, which achieves hierarchical assembly of DNA parts by utilizing Type IIS restriction enzymes to produce user-specified sticky ends on cut DNA fragments. This technique has been modularized and standardized, and includes different subfamilies of methods, the most widely adopted of which are the MoClo and Golden Braid standards.

Copper microenvironments in the human body define patterns of copper adaptation in pathogenic bacteria.

Copper is an essential micronutrient for most organisms that is required as a cofactor for crucial copper-dependent enzymes encoded by both prokaryotes and eukaryotes. Evidence accumulated over several decades has shown that copper plays important roles in the function of the mammalian immune system. Copper accumulates at sites of infection, including the gastrointestinal and respiratory tracts and in blood and urine, and its antibacterial toxicity is directly leveraged by phagocytic cells to kill pathogens.

Synthetic biology approaches to copper remediation: bioleaching, accumulation and recycling.

One of the current aims of synthetic biology is the development of novel microorganisms that can mine economically important elements from the environment or remediate toxic waste compounds. Copper, in particular, is a high-priority target for bioremediation owing to its extensive use in the food, metal and electronic industries and its resulting common presence as an environmental pollutant. Even though microbe-aided copper biomining is a mature technology, its application to waste treatment and remediation of contaminated sites still requires further research and development.

Copper tolerance in bacteria requires the activation of multiple accessory pathways.

Copper is a required micronutrient for bacteria and an essential cofactor for redox-active cuproenzymes. Yet, excess copper is extremely toxic, and is exploited as a bacteriocide in medical and biotechnological applications and also by the mammalian immune system. To evade copper toxicity, bacteria not only control intracellular copper homeostasis, but they must also repair the damage caused by excess copper.

SLAC wrist in the absence of recognised trauma and CPPD.

Purpose: This comparative cohort study was designed to determine whether non-traumatic SLAC wrist exists, and is associated with abnormal carpal bone kinematics (specifically, decreased lunate flexion).

Methods: SLAC patients with no recognised history of upper extremity trauma were prospectively compared with an age-matched control group.

Results: Thirty-five subjects (69 wrists), included 33 non-traumatic SLAC wrists and 36 control wrists.

Initial experience with the oxford unicompartmental knee arthroplasty.

Our initial experience with mobile bearing medial compartment unicompartmental arthroplasty (UKA) is presented to highlight lessons that have been learned to avoid short-term failures. Consecutive cases of the Oxford medial UKA performed between February 2001 and April 2006 were reviewed to derive those cases that were revised to total knee arthroplasty (TKA). There were 545 patients available with mean age and body mass index of 65.

Clinical examination of scaphoid fractures.

Undetected scaphoid fractures may lead to complications, including nonunion, malunion, avascular necrosis, and wrist arthritis. A competent physical examination is essential for the diagnosis of scaphoid fractures in the setting of occult fractures presenting with normal radiographs. The differential diagnosis of occult scaphoid fractures includes acute tears of the scaphoid-lunate ligament, Kienbock's disease, occult ganglion, nondisplaced radial styloid fractures, and injury to the radial aspect of the radio-scapho-capitate ligament.

Physical examination of the wrist.

Physical examination of the wrist requires knowledge of wrist anatomy and pathology to make a diagnosis or narrow the differential diagnosis. Symptoms are provoked by palpation and signs are produced by manipulation. Negative findings elsewhere in the wrist are important.

Ulnar styloid triquetral impaction.

Background: Ulnar styloid triquetral impaction (USTI), one of many causes of ulnar sided wrist pain, is a pathological entity with clear clinical and radiographic features, distinct and different from the impaction of the ulnar head against the lunate or ulno-carpal impaction (UCI). Pain is ulnar and point-tenderness is present precisely over the ulnar styloid as opposed to the proximal lunate in UCI. The provocative maneouvre of dorsiflexion in pronation followed by supination is markedly different from the ulnar deviation grind test maneouvres used to diagnose UCI.

Physical examination of the wrist.

Physical examination of the wrist requires knowledge of wrist anatomy and pathology to make a diagnosis or narrow the differential diagnosis. Symptoms are provoked by palpation and signs are produced by manipulation. Negative findings elsewhere in the wrist are important.

Cognitive dysfunction after total knee arthroplasty: effects of intraoperative cerebral embolization and postoperative complications.

Cerebral emboli identified as high-intensity transient signals (HITS) occur during total knee arthroplasty (TKA). Their effects on cognitive outcome remain speculative. Intraoperative HITS and postoperative complications were correlated with the cognitive function of TKA patients.

The effect of the wafer procedure on pressure in the distal radioulnar joint.

Purpose: To investigate the effect of the wafer procedure on pressure within the distal radioulnar joint.

Methods: The effect of increasing transverse distal ulnar head resection with preservation of the ulnar styloid was evaluated in 4 fresh frozen cadaver arms. Specimens were tested in neutral rotation.

Autologous osteoarticular transfer from the proximal tibiofibular joint to the scaphoid and lunate facets in the treatment of severe distal radial fractures: a report of two cases.

Purpose: This study was conducted to determine the appropriateness of using the articular cartilaginous surfaces of the proximal tibiofibular joint to resurface damaged distal radial articular surfaces and to assess the clinical results in the first 2 patients.

Method: Cadaveric specimens of the facets of the proximal tibiofibular joints and distal radius were sized and compared. Two patients underwent transfer of a fibular facet.

Transcranial Doppler characteristics of different embolic materials during in vivo testing.

Purpose: The authors investigated whether ultrasonic characteristics of embolic signals could be used to differentiate embolic composition.

Materials And Methods: The authors analyzed high-intensity transient signals (HITS) from 3 patients with patent foramen ovale during the bubble contrast test and during total joint replacement surgery. In 3 anesthetized dogs, latex microspheres, fat particles, and air bubbles were injected into the internal carotid artery and HITS were identified in the cerebral circulation.

Refracture rate after plate removal from the radial metaphysis.

Objectives: To document the refracture rate after removal of internal fixation at the metaphyseal region of the distal radius and to compare this rate to that associated with diaphyseal plate removal reported in the literature.

Design: A chart review with telephone follow-up.

Setting: Three tertiary care hospitals (in Ottawa, Burlington, Vt.

Systemic fat and thrombus embolization in patients undergoing total knee arthroplasty with regional heparinization.

A double-blind, randomized, controlled study was undertaken to determine if a technique of intraoperative anticoagulation would decrease the incidence or severity of venous embolization after tourniquet release during total knee arthroplasty. Sixty-six patients were randomized to receive either the heparin or placebo treatment. Transesophageal echocardiography was performed before and after tourniquet release to detect embolic material in the right atrium.

The treatment of pseudoarthrosis of the scaphoid by bone grafting and three methods of internal fixation.

Objectives: To measure the rate of union in patients with pseudoarthosis of the scaphoid, treated with trapezoidal bone grafting as outlined by Fernandez and 1 of 3 methods of internal fixation and to compare unions versus nonunions and potential predictors of union to determine if associations exist.

Design: A retrospective radiologic study of scaphoid pseudoarthroses.

Setting: Division of Orthopedic Surgery, Ottawa Hospital, General Site, a tertiary care facility.

Self-reported disability following distal radius fractures: the influence of hand dominance.

The purpose of this study was to record the spectrum of self-reported disability following distal radius fractures and to gauge for differences in hand dominance in the use of subjective outcome data. Items were generated through patient interviews, literature review, and peer consultation. Fifty-three items were evaluated by a group of 55 patients recovering from a fracture of the distal radius, which established the prevalence, mean severity score, and overall severity score (or impact) of each item as it related to physical function and social/emotional impact.

Histologic analysis of fetal ulnar variance.

Twenty-eight fetal wrists aged 5 to 21 weeks gestation were examined histologically to assess ulnar variance. There was a trend from ulna negative to ulna neutral among this population. Of 10 wrists in group I (5-8 weeks gestation), 8 were ulna negative and 2 were ulna neutral.

Injury to the Scapholunate Ligaments.

In brief Sprains of the ligament complex between the scaphoid and lunate bones may be more difficult to diagnose than other wrist injuries. However, patients will have characteristic localized pain and, in severe ruptures, diagnostic radiographic abnormalities. Minor scapholunate sprains usually heal with no sequelae, but severe sprains may lead to localized arthritis if the ligament complex is not repaired surgically.

Objective comparison of manual dexterity in physicians and surgeons.

Recent interest in the assessment of manual dexterity of surgical residency applicants prompted an investigation of psychomotor skills in surgeons and physicians. The Purdue Pegboard and Minnesota Manual Dexterity tests were given to 57 subjects. Analysis of the data revealed no significant difference in dexterity between medical and surgical residents, suggesting that medical students do not select specialty training programs because of the presence or absence of manual skills.