Emittance studies of the Spallation Neutron Source external-antenna H- ion source.

A new Allison-type emittance scanner has been built to characterize the ion sources and low energy beam transport systems at Spallation Neutron Source. In this work, the emittance characteristics of the H(-) beam produced with the external-antenna rf-driven ion source and transported through the two-lens electrostatic low energy beam transport are studied. The beam emittance dependence on beam intensity, extraction parameters, and the evolution of the emittance and twiss parameters over beam pulse duration are presented.

Control system for the Spallation Neutron Source H- source test facility Allison scanner.

Spallation Neutron Source is currently in progress of a multiyear plan to ramp ion beam power to the initial design power of 1.4 MW. Key to reaching this goal is understanding and improving the operation of the H(-) ion source. An Allison scanner was installed on the ion source in the test facility to support this improvement. This paper will discuss the hardware and the software control system of the installed Allison scanner. The hardware for the system consists of several parts. The heart of the system is the scanner head, complete with associated bias plates, slits, and signal detector. There are two analog controlled high voltage power supplies to bias the plates in the head, and a motor with associated controller to position the head in the beam. A multifunction data acquisition card reads the signals from the signal detector, as well as supplies the analog voltage control for the power supplies. To synchronize data acquisition with the source, the same timing signal that is used to trigger the source itself is used to trigger data acquisition. Finally, there is an industrial personal computer to control the rest of the hardware. Control software was developed using National Instruments LABVIEW, and consists of two parts: a data acquisition program to control the hardware and a stand alone application for offline user data analysis.

Use of percutaneous ethanol injection for treatment of bilateral hyperplastic thyroid nodules in cats.

OBJECTIVE: To determine the efficacy and safety of percutaneous ethanol injection (PEI) for the treatment of hyperthyroidism caused by bilateral hyperplastic thyroid nodules in cats. DESIGN; Prospective study. ANIMALS: 7 cats. PROCEDURE: Hyperthyroidism was diagnosed on the basis of clinical signs and increased serum total thyroxine (TT4) concentrations. The presence of 2 cervical thyroid nodules was confirmed by use of ultrasonography and technetium Tc 99m albumin thyroid scans. After the death of 1 cat that received PEI in both thyroid nodules at the same time, the protocol was changed to injecting ethanol into 1 nodule at a time, with at least 1 month between injections. Clinical signs, serum TT4 concentrations, serum ionized calcium concentrations, laryngeal function, findings on ultrasonographic examinations of the ventral cervical region, and results of thyroid scans were monitored. RESULTS: Serum TT4 concentrations transiently decreased in all 6 cats (into the reference range in 5 of 6 cats) within 4 days of the first staged ethanol injection. Each subsequent injection resulted in a transient decrease in serum TT4 concentration. The longest period of euthyroidism was 27 weeks. Adverse effects included Horner's syndrome, dysphonia, and laryngeal paralysis. One cat died of unrelated causes. One cat underwent bilateral thyroidectomy, 2 cats were treated with methimazole, and 2 cats that had increased serum TT4 concentrations were not treated further, because they remained clinically normal. CONCLUSIONS AND CLINICAL RELEVANCE: Percutaneous ethanol ablation of bilateral thyroid nodules as a treatment for cats with hyperthyroidism is not recommended. This treatment is not as efficacious as the medical and surgical treatments presently used.

Percutaneous ultrasonographically guided radiofrequency heat ablation for treatment of primary hyperparathyroidism in dogs.

OBJECTIVE: To evaluate the efficacy and safety of ultrasonographically guided radiofrequency heat ablation of parathyroid masses in dogs with primary hyperparathyroidism. DESIGN: Clinical trial. ANIMALS: 11 dogs. PROCEDURE: In all dogs, either 1 or 2 parathyroid masses were evident ultrasonographically. Dogs were anesthetized, and a 20-gauge over-the-needle catheter was directed into the parathyroid mass via ultrasonographic guidance. Radiofrequency heat was applied to the stylet of the catheter until there was sonographically apparent change to the entire parenchyma of the mass. Serum total and ionized calcium and parathyroid hormone concentrations were monitored daily for 5 days after the ablation procedure and again at 1, 2, and 3-month intervals, if possible. Dogs were monitored for adverse effects. RESULTS: One treatment was required in 6 dogs, 2 treatments were required in 2 dogs, and treatment was unsuccessful in 3 dogs. Serum total and ionized calcium concentrations were within reference ranges within 2 days of the last procedure in all 8 successfully treated dogs. Serum parathyroid hormone concentration was decreased 24 hours after treatment in all 8 dogs. Hypocalcemia developed in 5 of the 8 successfully treated dogs, all of which required treatment. One dog had a transient voice change. Other adverse effects were not reported. CONCLUSIONS AND CLINICAL RELEVANCE: Ultrasonographically guided radiofrequency heat ablation of parathyroid masses is a safe and effective alternative to surgery in dogs with primary hyperparathyroidism.

Evaluation of interoperator variance in shunt fraction calculation after transcolonic scintigraphy for diagnosis of portosystemic shunts in dogs and cats.

OBJECTIVE: To determine interoperator variance in shunt fraction calculation. DESIGN: Case series. SAMPLE POPULATION: 101 transrectal portoscintigraphic studies. PROCEDURE: Results of dynamic portoscintigraphic studies were reviewed by 4 radiologists without knowledge of signalment, history, or medical profile. Results were judged to be negative or positive on the basis of the dynamic scan. Composite images were formulated, and hand-drawn regions of interest were determined for the heart and liver. Time-activity curves were generated, time-zero points were selected, curves were integrated during a 10-second interval, and shunt fractions were calculated. RESULTS: Radiologists were in agreement regarding positive versus negative results for 99 of 101 studies. Interoperator variance in shunt fraction calculation ranged from 0.4 to 59.6%. For 51 studies with positive results, variance ranged from 2.5 to 59.6% (mean +/- SD, 22.8 +/- 14.5%); differences among reviewers were significant. For 48 studies with negative results, variance in shunt fraction ranged from 0.4 to 25.9% (mean, 5.3 +/- 5.8%); significant differences among reviewers were not detected. Shunt fraction calculations were not exactly reproducible among radiologists in 94 and 100% of studies with negative or positive results, respectively. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that shunt fraction values are not reproducible among operators. Range in variability was greater in studies with positive results. This factor may be of particular clinical importance in reassessment of patients after incomplete shunt ligation.

Modulation of gonococcal piliation by regulatable transcription of pilE.

The gonococcal pilus, a member of the type IV family of pili, is composed of numerous monomers of the pilin protein and plays an important role in the initiation of disease by providing the primary attachment of the bacterial cell to human mucosal tissues. Piliation also correlates with efficient DNA transformation. To investigate the relationships between these pilus-related functions, the piliation state, and the availability of pilin, we constructed a derivative of MS11-C9 (DeltapilE1) in which the lacIOP regulatory sequences control pilE transcription. In this strain, MS11-C9.10, the steady-state levels of pilin mRNA and protein directly correlate with the concentration of IPTG (isopropyl-beta-D-thiogalactopyranoside) in the growth medium and can reach near-wild-type levels of expression. Transmission electron microscopy (TEM) demonstrated that the number of pili per cell correlated with the steady-state expression levels: at a low level of transcription, single long pili were observed; at a moderate expression level, many singular and bundled pili were expressed; and upon full gene expression, increased lateral association between pili was observed. Analysis of pilus assembly by TEM and epithelial cell adherence over a time course of induction demonstrated that pili were expressed as early as 1 h postinduction. Analysis at different steady-state levels of transcription demonstrated that DNA transformation efficiency and adherence of MS11-C9.10 to transformed and primary epithelial cells also correlated with the level of piliation. These data show that modulation of the level of pilE transcription, without a change in pilE sequence, can alter the number of pili expressed per cell, pilus bundling, DNA transformation competence, and epithelial cell adherence of the gonococcus.

Elective plastic surgery in a Jehovah's Witness: a case series and review of the literature.

"Bloodless" plastic surgery in the Jehovah's Witness patient is an area that has received little attention in the surgical literature. Given the unique and firmly held beliefs of this group of patients, caring for them can be particularly challenging for the plastic surgeon. The authors report a case of bilateral breast reconstruction with saline-filled implants complicated by a postoperative hematoma and one involving a staged approach to massive breast reduction, both in Jehovah's Witness patients. A third patient involving a staged panniculectomy for a complicated wound infection is also described. The historical background, philosophical views, ethical issues, legal aspects, surgical outcomes, and management techniques relevant to caring for this unique patient population are also reviewed in detail.

Scintigraphic detection of equine orthopedic infection using Tc-HMPAO labeled leukocytes in 14 horses.

The aim of this study was to evaluate the diagnostic value of 99mTc-HMPAO leukocyte scintigraphy (LS) by means of a retrospective review of its use in 14 horses that were evaluated for orthopedic infection as a cause of lameness. A total of 17 LS exams were performed in 14 horses. LS studies were positive in 10 of 14 horses. A bacterial infection was confirmed with cytology or culture in 9 of 10 positive horses. Negative LS studies occurred in 4 of 14 horses. Necropsy confirmed the lack of infection in 2 of the 4 horses. Other clinical data and a favorable clinical outcome supported a negative study in the other 2 horses. No false negative or false positive studies were identified. It may be concluded that HMPAO-LS is an effective tool for the diagnosis of orthopedic infection in horses.

The diagnosis of urinary incontinence and abnormal urination in dogs and cats.

No single technique allows one to diagnose all causes of urinary incontinence and abnormal increased frequency of urination. Cystography is indicated for cases of abnormal urinary bladder position, size, or shape. Ultrasonography is best for mass effects, calculi, and extrinsic nonskeletal abnormalities. The combined cystography and excretory urography technique is recommended for diagnosing ectopic ureteral insertions. Computerized tomography and MR imaging are indicated when the techniques described previously fail to elucidate the problem sufficiently, but these methods are usually not selected as primary diagnostic techniques.

A homologue of the recombination-dependent growth gene, rdgC, is involved in gonococcal pilin antigenic variation.

Neisseria gonorrhoeae pilin undergoes high-frequency changes in primary amino acid sequence that aid in the avoidance of the host immune response and alter pilus expression. The pilin amino acid changes reflect nucleotide changes in the expressed gene, pilE, which result from nonreciprocal recombination reactions with numerous silent loci, pilS. A series of mini-transposon insertions affecting pilin antigenic variation were localized to three genes in one region of the Gc chromosome. Mutational analysis with complementation showed that a Gc gene with sequence similarity to the Escherichia coli rdgC gene is involved in pilus-dependent colony phase variation and in pilin antigenic variation. Furthermore, we show that the Gc rdgC homologue is transcriptionally linked in an operon with a gene encoding a predicted GTPase. The inability to disrupt expression of this gene suggests it is an essential gene (engA, essential neisserial GTPase). While some of the transposon mutations in rdgC and insertions in the 5'-untranslated portion of engA showed a growth defect, all transposon insertions investigated conferred an aberrant cellular morphology. Complementation analysis showed that the growth deficiencies are due to the interruption of RdgC expression and not that of EngA. The requirement of RdgC for efficient pilin variation suggests a role for this protein in specialized DNA recombination reactions.

Ultrasonographic evaluation of the canine shoulder.

The aim of this study was to determine the normal ultrasonographic anatomy of the canine shoulder. Fourteen shoulders from 7 clinically normal mid-sized dogs were radiographed and imaged using high frequency ultrasound. Each shoulder was isolated postmortem, and the ultrasonographic and gross anatomy was studied during dissection. The ultrasonographic appearance of the shoulder specimens was similar to that found in the live dogs. Twenty-four shoulders isolated postmortem from 12 variably sized dogs were also used to characterize the normal ultrasound anatomy over a range of sizes. Important anatomic structures that could be consistently evaluated were the biceps tendon and bursa, the bicipital groove surface, the supraspinatous tendon, the infraspinatous tendon, the teres minor tendon, and the caudal aspect of the humeral head. Results of ultrasonographic examination of 4 dogs with shoulder lameness are described to illustrate some applications of canine shoulder ultrasonography in the evaluation of the canine shoulder. In these dogs, ultrasound was a valuable tool to evaluate effusion and synovial proliferation within the bicipital bursa, supraspinatous and biceps tendinitis, biceps tendon strain, and dystrophic calcification.

Percutaneous ultrasound-guided chemical parathyroid ablation for treatment of primary hyperparathyroidism in dogs.

OBJECTIVE: To evaluate the efficacy, feasibility, and safety of ultrasound-guided chemical ablation of parathyroid masses in dogs with primary hyperparathyroidism. DESIGN: Prospective clinical trial. ANIMALS: 8 dogs. PROCEDURE: In all dogs, a solitary parathyroid mass was evident ultrasonographically. Dogs were anesthetized with propofol, and a 27-gauge needle was directed into the parathyroid mass under ultrasound guidance. Ethanol (96%) was injected into the mass until there was evidence of diffusion of fluid throughout the mass. Serum total calcium, ionized calcium, phosphorus, and parathyroid hormone (PTH) concentrations were monitored daily for 5 to 7 days after the ablation procedure and again 1, 3, and 6 months after the procedure. Dogs were also monitored for adverse effects. Follow-up ultrasonography was performed 5 days and 1 month after the ablation procedure. RESULTS: One injection was required in 7 dogs, and 2 injections were required in 1. Serum total and ionized calcium concentrations were within reference ranges within 24 hours after treatment in 7 dogs and within 5 days in 1 dog. Serum PTH concentration decreased and serum phosphorus concentration increased within 24 hours after treatment in all 8 dogs. Transient hypocalcemia developed in 4 dogs during the first 5 days after treatment, but only 1 dog required treatment for hypocalcemic tetany. Hypercalcemia recurred in 1 dog 1 month after the procedure and surgical removal of the parathyroid mass was required. Other adverse effects were not reported. CONCLUSIONS AND CLINICAL RELEVANCE: Ultrasound-guided chemical ablation of parathyroid masses is a safe and effective alternative to surgery for dogs with primary hyperparathyroidism.

A multidisciplinary approach to wound care in the hospitalized patient.

Wound care services at a tertiary level teaching hospital were reorganized to improve patient care and control costs. A multidisciplinary wound care team was implemented to develop an aggressive, proactive approach to prevent and minimize pressure ulceration. Outcome data demonstrate the efficacy of the wound care team.

Thrombospondin-1 and its CSVTCG-specific receptor in wound healing and cancer.

Growth factors play a crucial role in the regulation of cellular proliferation and matrix degradation in wound healing and cancer. We have shown that thrombospondin 1 (TSP-1) and its cysteine-serine-valine-threonine-cysteine-glycine (CSVTCG)-specific receptor play a key role in cell invasion and matrix degradation in different carcinomas. The present study was done to determine whether TSP-1 and its receptor show a similar pattern of expression in wound healing and cancer. Expression and localization of TSP-1 and its receptor were determined in fetal wounds, adult burn wounds, and different human malignancies by immunohistochemical staining and computerized image analysis. In healing wounds, TSP-1 was expressed in the stroma early in the process, followed by a steep decline. The TSP-1 receptor localized to neovessels and highly proliferating cells (i.e., fibroblasts, basal cells), its levels remaining relatively constant. Cancer cells and tumor-associated microvessels expressed the TSP-1 receptor, whereas TSP-1 localized predominantly to the tumor-associated stroma. These data suggest a critical role for TSP-1 and its CSVTCG-specific receptor in wound healing and cancer.

Comparisons between colony phase variation of Neisseria gonorrhoeae FA1090 and pilus, pilin, and S-pilin expression.

The gonococcal pilus is a primary virulence factor, providing the initial attachment of the bacterial cell to human mucosal tissues. Pilin, the major subunit of the pilus, can carry a wide spectrum of primary amino acid sequences which are generated by the action of a complex antigenic variation system. Changes in the pilin amino acid sequence can produce different pilus-dependent colony morphotypes, which have been previously shown to reflect phase variation of pili on the bacterial cell surface. In this study, we further examined the relationships between changes in pilus-dependent colony morphology, pilin sequence, pilus expression, and pilus function in Neisseria gonorrhoeae FA1090. A group of FA1090 colony variants expressed different pilin sequences and demonstrated different levels of pilin, S-pilin, and pilus expression. The analysis of these colony variants shows that they do not represent two distinct phases of pilus expression, but that changes in pilin protein sequence produce a spectrum of S-pilin production, pilus expression, and pilus aggregation levels. These different levels of pilus expression and aggregation influence not only colony morphology but also DNA transformation efficiency and epithelial cell adherence.

Outcome assessment of an in-hospital cross-functional wound care team.

A multidisciplinary wound care team was developed at the Medical College of Pennsylvania Hospital in 1993 to standardize wound management, appropriately allocate resources, prevent the occurrence of hospital-acquired decubitus ulcers, and effectively manage existing pressure ulcers. This report presents 4 years of prevalence survey data (n = 690 patients over 4 years), which affords an outcome analysis regarding the efficacy of the multidisciplinary wound care team. A significant reduction in the number of patients with pressure ulcers, hospital acquired pressure ulcers, and patients with hospital acquired ulcers occurred. There was, also, a significant improvement in skin integrity documentation, and in the implementation of nutritional assessments. These findings suggest that the multidisciplinary wound care team has been an effective means of gaining some control of decubitus ulcers, which are associated with increased patient morbidity and have an adverse economic impact on hospitals.

Soft-tissue complications of intra-arterial chemotherapy for extremity sarcomas.

High-grade sarcomas have a high rate of local recurrence as well as distant metastases. This has led to the development of intra-arterial chemotherapy (IAC) as part of a multimodal approach to control local disease and/or reduce the extent of surgical resection. Intra-arterial catheters are positioned by an interventional radiologist into the feeding vessels of the tumor. Adriamycin and 5-fluorodeoxyuridine are infused intra-arterially. Cisplatinum, with or without granulocyte colony stimulating factor, is given systemically. Patients usually experience acute self-limited soft-tissue inflammation in the treated area. In our experience of 118 patients, 3 patients experienced soft-tissue necrosis that required excision and reconstruction. The first was treated for synovial sarcoma of a metatarsal. After IAC with Adriamycin, she sloughed the skin, subcutaneous tissue, and some of the posterior compartment musculature of her calf. This tissue was debrided. A gastrocnemius flap and skin graft were used for coverage. She is free of disease and ambulatory. The second patient was treated with IAC Adriamycin for a radial head chondrosarcoma. She developed soft-tissue slough, which became infected with Pseudomonas. She required extensive debridement of the skin, subcutaneous tissue, and muscle, and was subsequently reconstructed with a latissimus flap and a split-thickness skin graft (STSG). She later developed a local recurrence requiring amputation. The latissimus was elevated and used to cover the distal stump. She also is free of disease. The third patient was treated with IAC Adriamycin for Ewing's sarcoma of the right femur. This was complicated by fat necrosis and persistent pain. Subsequent radiotherapy only worsened her symptoms. She underwent wide excision and muscle flap/STSG repair, which relieved her pain. She is currently ambulatory and free of disease. In conclusion, as the use of IAC continues, its complications may become more common. Our experience with this previously unknown entity is illustrated and therapeutic options are discussed.

Rapid detection and typing of herpes simplex virus DNA in clinical specimens by the hybrid capture II signal amplification probe test.

A second-generation signal amplification, nucleic acid-based test for the rapid detection and typing of herpes simplex virus (HSV) DNA was developed and evaluated with artificial and clinical specimens. The analytical sensitivity of the Hybrid Capture II (HC II) HSV DNA assay was determined by testing either cloned HSV DNA or total genomic HSV DNA titrations and resulted in detection thresholds of between 5 x 10(3) and 1 x 10(4) copies per assay. Specificity was assessed by testing a panel of bacteria and viruses commonly found in the female genital tract. Sensitivity was assessed by testing 112 ulcerative genital lesions by the HC II assay and comparing the results to those obtained by routine cell culture. Discrepant results were resolved by PCR testing. After resolution of the discrepant results, the sensitivity of the HC II assay compared to the consensus result (the results of two of three tests, the HC II assay, culture, and PCR, were in agreement) was 93.2% (41 of 44 specimens), and the specificity was 100% (60 of 60 specimens). Culture gave a sensitivity of 84.1% (37 of 44 specimens) and a specificity of 100% (60 of 60 specimens) compared to the consensus result. The results of HSV typing by the HC II assay and culture agreed in all cases. The HC II assay is a rapid and accurate assay for detecting and typing HSV types 1 and 2, with a sensitivity comparable to that of culture and greater ease of use than culture.

Stationary arterial wave phenomena.

The case of a 38-year-old woman who was struck by an automobile is presented. The workup for lower extremity injuries revealed stationary arterial waves. Recognition of this arteriographic finding may avoid unnecessary confusion or exploration.

Giant splenic artery aneurysm.

Giant aneurysms of the splenic artery are uncommon. The mean size of splenic artery aneurysms is reported to be 2.1 cm; they are rarely larger than 3 cm. We present two cases in which the splenic artery aneurysm was larger than 8 cm, discuss the management and operative approach to these infrequently encountered entities, and provide a brief review of the relevant literature.