A method for isolation of sequences missing in one of two related genomes

We describe a novel technique for isolation of sequences that are present in one genome (tracer), but absent in another (driver). Tracer DNA, cleaved with Sau 3A and capped with a single stranded PCR adapter, is allowed to hybridize with an excess of sheared biotinylated driver; biotinylated DNA and its hybrids with the tracer are removed by phenol/chloroform extraction after incubation with streptavidin. After several rounds of subtraction the ends of self-annealed tracer molecules from the nonextractable fraction are filled-in with Tag polymerase and amplified, using the single stranded PCR adapter as a primer. The method has been applied to purification of fragments from a 2.9 kb plasmid added to E. coli DNA at equimolar quantity. Plasmid derived fragments (250-1000 bp), initially comprising 1/1400th part of tracer DNA, were purified to homogeneity after two rounds of subtraction followed by PCR.     

An audit of magnetic resonance imaging in the paediatric orthopaedic setting

AIMS: To determine when magnetic resonance imaging (MRI) is helpful in the management of a selected group of paediatric orthopaedic patients. METHODS: A retrospective analysis of 131 MRI scans was undertaken with allocation into seven categories based on clinical presentation. RESULTS: MRIs performed for spinal, congenital and intra-articular pathology, as well as for growth plate assessment correlated well with subsequent clinical and/or surgical findings. Three of ten MRIs (30%) incorrectly assessed whether a foreign body was present with a sensitivity of 0.60 and specificity of 0.80. Three of 20 MRIs (15%) could not accurately distinguish between oedema/effusion and frank infection. Here sensitivity was 1.00 and specificity was 0.73. MRIs performed for assessment of tumours were accurate with respect to margins and extent. Assessment of pathology with MRI was never the indication for MRI, thus it was not surprising that in four of 27 soft tissue tumours (sensitivity of 0.88 and specificity of 0.63) MRI did not correlate with subsequent histological findings. CONCLUSIONS: MRI plays an important role in the assessment of a wide range of musculo-skeletal pathology. MRI does not, and could not be expected to, replace the need for incisional biopsy for tumour diagnosis. It must be used with caution where tissues have been previously explored for foreign bodies. Interpretation of MRI in musculoskeletal infection must consider its timing in the evolution of the patient's infection.     

Management of psychiatric symptoms in medically ill patients in the homecare setting

Nurses with critical care knowledge and experience increasingly provide technologically advanced care to patients at home who often present comorbid psychiatric symptoms. Failure to accurately recognize and provide appropriate intervention can be devastating for patients because these symptoms can exacerbate the medical condition and may lead to mortality. The Biopsychosocial Model and the Transactional Model of Stress were presented as guides for nursing practice. Practice is directed at 1) understanding the patient's perception of events, 2) involving the caregiver(s) in the patient's recovery, and 3) enhancing the individual's adaptive coping efforts and resources. The article attempts to guide nurses in making decisions on when to consult and collaborate with an APPN to achieve desired patient outcomes.     

Effect of smoking cessation counseling on recovery from alcoholism: findings from a randomized community intervention trial

AIMS: To assess the effects of a smoking cessation program for recovering alcoholics on use of alcohol, tobacco and illicit drugs after discharge from residential treatment. DESIGN AND SETTING: A randomized community intervention trial design was employed in which 12 residential drug treatment centers in Iowa, Kansas and Nebraska were matched and then randomly assigned to the intervention or control condition. PARTICIPANTS: Approximately 50 adult residents (inpatients) from each site were followed for 12 months after treatment discharge. INTERVENTION: Participating residents in the six intervention centers received a 4-part, individually tailored, smoking cessation program while those in the six control sites received usual care. FINDINGS: Both moderate and heavy drinking rates were reduced in the intervention group. Intervention site participants were significantly more likely than controls to report alcohol abstinence at both the 6-month (OR = 1.59, 95%CI: 1.09-2.35) and 12-month assessment (OR = 1.84, 95%CI: 1.28-2.92). Illicit drug use rates were comparable. Effect of the intervention on tobacco quit rates was not statistically significant. CONCLUSIONS: Counseling alcoholics in treatment to quit smoking does not jeopardize the alcohol recovery process. However, low-intensity tobacco interventions are unlikely to yield high tobacco quit rates.     

Ruminal metabolism of leafy spurge in sheep and goats: A potential explanation for differential foraging on spurge by sheep,goats, and cattle

Leafy spurge (Euphorbia esula) is an introduced forb that is invading western rangelands. Goats (Capra hircus) readily graze the plant, but cattle (Bos tarus) generally and sheep (Ovis aries) locally appear to develop conditioned flavor aversions to leafy spurge. They either avoid the plant entirely or graze it reluctantly. We hypothesized that: (1) a diterpene diester that can occur in leafy spurge was an aversive agent, and (2) diet selection differences among ruminant species may be partly a function of differential ruminai metabolism of aversive phytochemicals, and further that cattle and sheep may be reluctant to graze leafy spurge because their ruminai microbes do not metabolize certain leafy spurge chemicals as do ruminai microbes in goats. Sheep did not develop an aversion to a novel food when its consumption was followed by an intravenous injection of ingenol 3,20-dibenzoate (P=0.34). Sheep did develop an aversion to a novel food when its intake was followed by a dose of leafy spurge fermented with sheep ruminai digesta, but not when followed by a dose of leafy spurge fermented with goat ruminai digesta (P= 0.03). This suggests that goat ruminai microbes may modify leafy spurge such that it does not elicit an aversion in sheep.This research was supported in part by a grant from the Cooperative States Research Service (91-38300-6158). All experimental procedures with ruminants followed a protocol approved by the U.S. Sheep Experiment Station's Animal Care and Use Committee. Mention of trade names or companies does not constitute an implied warranty by USDA or the authors.     

Hierarchical mapping of spot defects to catastrophic faults-designand applications

This paper describes the defect to fault mapper (DEFAM), and its use in integrated circuit test quality analysis and yield prediction. DEFAM analyzes the effects of spot defects on a design during the manufacturing process, and computes the probability of circuit faults that may occur. Unlike traditional tools, DEFAM exploits the design hierarchy to reduce the required analysis effort. It also reports faults in terms of the design hierarchy, which is essential for many applications. Yield analysis results are given for CMOS designs of up to 164 K transistors. Test quality analysis results are given for an adder module     

Long-wavelength transimpedance optical receiver performance enhancement using cooled germanium avalanche photodiodes

An optical sensitivity improvement of 1.5 dB was produced by moderate cooling of a commercially available 100 ?m p+-n Ge APD in a transimpedance receiver, built on a standard printed circuit board. At 1.3 ?m and 140 Mbaud, ?45.2 dBm was achieved, making this receiver highly competitive where cooling is permitted.     

Minimum stress design of transversely isotropic sandwich plates based on higher-order theory

The minimum stress design of thick laminated sandwich plates is given based on a higher-order theory of plates which includes the effects of the normal and shear deformation. The surface layers are made of a transversely isotropic composite material and the results are given for isotropic and transversely isotropic core layers which can model a variety of materials including honcycomb. The theory is implemented using dedicated symbolic computation routines developed in the C programming language. The analysis is incorporated into an optimization algorithm to determine the optimal thicknesses of the surface layers for the minimum stress deisgn of three-layered sandwich plates. Numerical results are given for plates under sinusoidal loading and the effects of various input parameters are investigated. The stress behaviour which cannot be studied using a classical theory or a shear deformable theory only is indicated.     

The radiographic and imaging characteristics of porous tantalum implants within the human cervical spine

STUDY DESIGN: Seven cadaveric cervical spines were implanted with a porous tantalum spacer and a titanium alloy spacer, and their radiographic and imaging characteristics were evaluated. OBJECTIVE: To determine the radiographic characteristics of porous tantalum and titanium implants used as spacers in the cervical spine. SUMMARY OF BACKGROUND DATA: Anterior decompressive surgery of the disc space or the vertebral body creates a defect that frequently is repaired with autologous bone grafts to promote spinal fusion. Donor site morbidity, insufficient donor material, and additional surgical time have spurred the development of biomaterials to replace or supplement existing spinal reconstruction techniques. Although the promotion of a solid bony fusion is critical, the implanted biomaterial should be compatible with modern imaging techniques, should allow visualization of the spinal canal and neural foramina, and should permit radiographic assessment of bony ingrowth. METHODS: Cadaveric spines containing the implants were imaged with plain radiography, computerized tomography, and magnetic resonance imaging. The image distortion produced by the implants was determined qualitatively and quantitatively. RESULTS: The tantalum and titanium spacers were opaque on plain radiographic films. On computed tomographic scans, more streak artifact was associated with the tantalum implants than with the titanium. On magnetic resonance imaging, the porous tantalum implant demonstrated less artifact than did the titanium spacer on T1- and T2-weighted spin echo and on T2*-weighted gradient-echo magnetic resonance images. Overall, the tantalum implant produced less artifact on magnetic resonance imaging than did the titanium spacer and therefore allowed for better visualization of the surrounding bony and neural structures. CONCLUSION: The material properties of titanium and porous tantalum cervical interbody implants contribute to their differential appearance in different imaging methods. The titanium implant appears to image best with computed tomography, whereas the porous tantalum implant produces less artifact than does the titanium implant on several magnetic resonance imaging sequences.     

Incomplete ossification of the tarsal bones in foals: 22 cases (1988-1996)

OBJECTIVE: To determine outcome for foals with incomplete ossification of the tarsal bones and to determine whether clinical and radiographic abnormalities at the time of initial examination were associated with outcome. DESIGN: Retrospective study. ANIMALS: 22 foals. PROCEDURE: Information on signalment, history, owner's initial complaint, clinical findings, whether tarsus valgus was evident, and radiographic abnormalities was obtained from medical records. Radiographic lesions were classified as type I (i.e., incomplete ossification with < 30% collapse of the affected bones) or type II (incomplete ossification with > 30% collapse and pinching or fragmentation of the affected bones). Follow-up information was obtained via telephone conversations with owners. RESULTS: Foals were between 1 day and 10 months old when first examined. Eleven were premature (i.e., < 320 days of gestation) or were twins. Sixteen had tarsus valgus. Severity of radiographic lesions was associated with outcome; 4 of 6 foals with type-I incomplete ossification of the tarsal bones performed as intended, but only 3 of 16 foals with type-II incomplete ossification of the tarsal bones performed as intended. CLINICAL IMPLICATIONS: For foals with incomplete ossification of the tarsal bones, severity of the radiographic lesions was associated with outcome. Foals with type-II incomplete ossification of the tarsal bones have a guarded prognosis for athletic soundness.