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Introduction: Little is known about missed opportunities (MOs) for HPV vaccination during primary care visits at which influenza vaccination is delivered., Methods: We extracted electronic health records for HPV vaccine-eligible 11-to-17-year-olds. We assessed the proportion of visits during which an influenza vaccine was given and an HPV vaccine was due, but not given (i.e., MOs)., Results: Of 56,135 eligible visits, 57.5% represented MOs for HPV vaccination. MOs were more common at visits where an initial versus subsequent HPV vaccine dose was due (68.6% vs. 31.3%) and for acute/chronic and nurse-only visits compared to preventive visits (74.0% and 80.2% vs. 36.7%). In a multivariable model, MOs were more likely for the initial HPV dose and for non-preventive visits, but did not vary by patient sex/age., Conclusions: HPV vaccine MOs were common during visits where influenza vaccine was administered. Increasing simultaneous administration of HPV and influenza vaccines could increase HPV vaccine coverage., Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: [Dr. Fiks had an independent research grant from Pfizer. He did not receive salary support, but the grant supported his research team. Dr. Fiks is the co-inventor of the Care Assistant decision and workflow support software. He has earned no income and no licensing agreement exists for the intervention. In the past year, Dr. Humiston has been a consultant to Sanofi Pasteur, which manufactures vaccines, although not HPV vaccine. No other disclosures were reported.]., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Like the mechanisms of action as adjuvants, the pharmacodynamics of injected forms of aluminum commonly used in vaccines are not well-characterized, particularly with respect to how differences in schedules impact accumulation and how factors such as genetics and environmental influences on detoxification influence clearance. Previous modeling efforts are based on very little empirical data, with the model by Priest based on whole-body clearance rates estimated from a study involving a single human subject. In this analysis, we explore the expected acute exposures and longer-term whole-body accumulation/clearance across three vaccination schedules: the current US Centers for Disease Control and Prevention (CDC) schedule, the current CDC schedule using low aluminum or no aluminum vaccines, and Dr. Paul Thomas' "Vaccine Friendly Plan" schedule. We then study the effects of an implicit assumption of the Priest model on whether clearance dynamics from successive doses are influenced by the current level of aluminum or modeled by the assumption that a new dose has its own whole-body dynamics "reset" on the day of injection. We model two additional factors: variation (deficiency) in aluminum detoxification, and a factor added to the Priest equation to model the potential impact of aluminum itself on cellular and whole-body detoxification. These explorations are compared to a previously estimated pediatric dose limit (PDL) of whole-body aluminum exposure and provide a new statistic: %alumTox, the (expected) percentage of days (or weeks) an infant is in aluminum toxicity, reflecting chronic toxicity. We show that among three schedules, the CDC schedule results in the highest %alumTox regardless of model assumptions, and the Vaccine Friendly Plan schedule, which avoids >1 ACV per office visit results in the lowest (expected) %alumTox. These results are conservative, as the MSL is derived from data used by FDA to estimate safety of aluminum in adult humans. These results demonstrate high potential utility of modeling variation in patient responses to aluminum. More empirical data from individuals who are suspected of being intolerant of aluminum from vaccines, evidenced by high aluminum retention, neurodevelopmental disorders and/or a myriad of chronic illnesses would help answer questions on whether the model predictions can be used to estimate parameter values tied to genetic factors including genomic sequence variation and family history of chronic illnesses tied to aluminum exposure., Competing Interests: Declaration of Competing Interest JLW is a (sometimes) compensated expert witness in cases in the US National Vaccine Injury Compensation Program involving cases in which ACVs have been identified as a potential cause of autoimmune disorders. PT receives income in the form of royalties from the sale of his book, and he receives income from the sale and administration of vaccines in his practice. EL and GM have no potential conflicts of interest to report., (Copyright © 2019 The Authors. Published by Elsevier GmbH.. All rights reserved.)

Objective: The use of duplex ultrasound (DUS) examinations for surveillance after fenestrated endovascular aneurysm repair (FEVAR) is not well-studied. Our objective was to further characterize normal and abnormal duplex findings in renal branch grafts after FEVAR., Methods: We retrospectively reviewed a single-center experience involving consecutive patients treated with Cook ZFEN devices between 2012 and 2017. Postoperative imaging consisted of a computed tomography (CT) scan at 1 month, 6 months, 1 year, and annually thereafter. As experienced progressed, DUS examination with or without concurrent CT scans were obtained in a nonstandardized protocol, particularly for patients with decreased renal function. Renal patency loss was defined as occlusion or stenosis of greater than 50% evaluated on 3-day renal artery center-line imaging., Results: A total of 116 patients were treated with FEVAR, of which 60 (51.7%) had concurrent CT and renal DUS images available for review. Six patients (10%) had limited ultrasound studies owing to bowel gas and were excluded. The study cohort therefore included 54 patients receiving of 94 renal fenestrated stents with a mean follow-up of 23 months. Twelve cases of renal patency loss in 10 patients (9 stenoses, 3 occlusions) were found on CT scanning, 11 (91.6%) of which had concurrent abnormalities found on ultrasound examination. Stents with compression at the junction of the main body exhibited significantly elevated mean Peak systolic velocities (PSV) compared with nonstenosed stents (349.2 cm/s vs 115.3 cm/s; P = .003). Stenosis in the most proximal portion of the stent (ie, within the main body) showed no difference in proximal PSV (86.0 cm/s vs 131.9 cm/s; P = .257); however, dampened PSV showed significant differences in the mid (17.5 cm/s vs 109.9 cm/s; P = .027) and distal (19.0 cm/s vs 78.3 cm/s; P = .028) segments compared with nonstenosed stents. All occluded stents demonstrated no flow detection. Proximal PSV served as a strong classifier for junctional stenosis (area under the curve, 0.98). A combined criterion of proximal PSV of greater than 215 cm/s or distal PSV of less than 25 cm/s resulted in a sensitivity of 91.6% and specificity of 85.3% for detecting patency loss. All stents that were compromised underwent successful secondary reintervention and restoration of patency., Conclusions: DUS imaging is a clinically useful modality for surveillance of renal branch grafts after FEVAR. Patterns of segmental velocity elevation (proximal PSV, >215 cm/s) and dampening in the distal renal indicate potential hemodynamic compromise and should prompt more aggressive workup or imaging and likely be considered for secondary intervention., (Copyright © 2019 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.)

Objective: Previous studies evaluating general anesthesia (GA) vs regional (epidural/spinal) anesthesia (RA) for infrainguinal bypass have produced conflicting results. The purpose of this study was to analyze the factors associated with contemporary use of RA and to determine whether it is associated with improved outcomes after infrainguinal bypass in patients with critical limb ischemia., Methods: Using the Vascular Quality Initiative infrainguinal database, a retrospective review identified all critical limb ischemia patients who received an infrainguinal bypass from 2011 through 2016. Patients were then separated by GA or RA. Primary outcomes were perioperative mortality, complications, and length of stay. Predictive factors for RA and perioperative outcomes were analyzed using a mixed-effects model to adjust for center differences., Results: There were 16,052 patients identified to have a lower extremity bypass during this time frame with 572 (3.5%) receiving RA. There was a wide variation in the use of RA, with 31% of participating centers not using it at all. Age (67.2 vs 70.3 years; P < .001), chronic obstructive pulmonary disease (25.7% vs 30.9%; P < .001), and urgency of the operation (75.7% vs 80.4%; P = .01) were found to be independently associated with receiving a regional anesthetic. Univariate and multivariate analysis demonstrated that length of stay (6.8 days vs 5.7 days; P < .01), postoperative congestive heart failure (2.3% vs 1.1%; P = .040), and change in renal function (5.7% vs 2.9%; P = .005) were all significant outcomes in favor of RA. There was a trend toward lower mortality rates; however, this did not reach statistical significance. Rates of myocardial infarction, pulmonary complications, and stroke were not found to be statistically different. Coarsened exact matching continued to demonstrate a difference in length of stay and rates of new-onset congestive heart failure in favor of RA., Conclusions: RA is an infrequent but effective form of anesthesia for infrainguinal bypass surgery. Elderly patients and those with underlying respiratory problems may benefit from this form of anesthesia. Further evaluation within institutions should be performed to identify which patients would most benefit from RA or GA., (Copyright © 2018 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.)

Objective: Endovascular aneurysm repair (EVAR) has become the standard of care for infrarenal aneurysms. Endografts are commercially available in proximal diameters up to 36 mm, allowing proximal seal in necks up to 32 mm. We sought to further investigate clinical outcomes after standard EVAR in patients requiring large main body devices., Methods: We performed a retrospective review of a prospectively maintained database for all patients undergoing elective EVAR for infrarenal abdominal aortic aneurysms at a single institution from 2000 to 2016. Only endografts with the option of a 34- to 36-mm proximal diameter were included. Requisite patient demographics, anatomic and device-related variables, and relevant clinical outcomes and imaging were reviewed. The primary outcome in this study was proximal fixation failure, which was a composite of type IA endoleak and stent graft migration >10 mm after EVAR. Outcomes were stratified by device diameter for the large-diameter device cohort (34-36 mm) and the normal-diameter device cohort (<34 mm)., Results: There were 500 patients treated with EVAR who met the inclusion criteria. A total of 108 (21.6%) patients received large-diameter devices. There was no difference between the large-diameter cohort and the normal-diameter cohort in terms of 30-day (0.9% vs 0.95%; P = .960) or 1-year mortality (9.0% vs 6.2%; P = .920). Proximal fixation failure occurred in 24 of 392 (6.1%) patients in the normal-diameter cohort and 26 of 108 (24%) patients in the large-diameter cohort (P < .001). There were 13 (3.3%) type IA endoleaks in the normal-diameter cohort and 16 (14.8%) in the large-diameter cohort (P < .001). Stent graft migration (>10 mm) occurred in 15 (3.8%) in the normal-diameter cohort and 16 (14.8%) in the large-diameter cohort (P < .001). After multivariate analysis, only the use of Talent (Medtronic, Minneapolis, Minn) endografts (odds ratio [OR], 4.50; 95% confidence interval [CI], 1.18-17.21) and neck diameter ≥29 mm (OR, 2.50; 95% CI, 1.12-5.08) remained significant independent risk factors for development of proximal fixation failure (OR, 3.99; 95% CI, 1.75-9.11)., Conclusions: Standard EVAR in patients with large infrarenal necks ≥29 mm requiring a 34- to 36-mm-diameter endograft is independently associated with an increased rate of proximal fixation failure. This group of patients should be considered for more proximal seal strategies with fenestrated or branched devices vs open repair. Also, this group likely needs more stringent radiographic follow-up., (Copyright © 2018 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.)

Background: Limited reports have documented the effect cardiac implantable electronic devices (CIEDs) have on arteriovenous (AV) access patency. Current recommendations suggest placing the access on the contralateral side of the CIEDs, as there is concern for increased central venous stenosis and access failure. The goal of this study is to review our single-center AV access patency rates for dialysis patients with an ipsilateral or contralateral side CIED., Methods: A retrospective review was performed from 2008 to 2016 at a single institution identifying all patients who have received a CIED and the diagnosis of end-stage renal disease (ESRD). Medical records were queried to identify each patient's dialysis access and whether it was ipsilateral or contralateral to the CIED. Primary outcomes of study were primary and secondary patency rates., Results: A total of 44 patients were identified to have ESRD and CIED. Of these patients, 28 patients with fistulas or grafts (13 ipsilateral and 15 contralateral) had follow-up with regards to their AV access. There were 3 primary failures in both groups. For patients who had the CIED placed after already starting the dialysis, patency was based on when the cardiac device was implanted. Primary patency for ipsilateral and contralateral access was 20.2 and 22.2 months, respectively. With secondary interventions, ipsilateral and contralateral mean patency was 39 and 48.8 months, respectively. Six-month and 1-year primary patency for arteriovenous fistula or arteriovenous graft on patients with ipsilateral access was 69.2% and 53.8%, respectively. Ipsilateral 1-year cumulative patency was 39 months., Conclusions: CIED may lead to stenosis or occlusion to one's AV access; however, primary assisted and secondary patency rates are still acceptable at 6 months and 1 year compared to Kidney Disease Outcomes Quality Initiative guidelines. Despite a CIED, a surgeon's algorithm should not lead to the abandonment of an ipsilateral access if the central venous system is patent., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Background:: We report the case of a 90-year old woman who presented with septic pulmonary emboli due to suppurative thrombophlebitis at an old peripheral intravenous site., Methods:: After unsuccessful treatment with antibiotics, the patient was taken to the operating room for excision and drainage of the purulent superficial vein., Results:: We review the literature and discuss the presentation, risk factors, treatment options, and complications of this often-overlooked disease entity., Conclusions:: Suppurative thrombophlebitis is a rare but morbid disease that requires a high level of clinical suspicion to diagnose.

Functionalised siloxane macromonomers, with properties designed for application as an injectable, in situ curable accommodating intraocular lens (A-IOL), were prepared via re-equilibration of a phenyl group-containing polysiloxane of very high molecular weight with octamethylcyclotetrasiloxane (D₄) and 2,4,6,8-tetra(n-propyl-3-methacrylate)-2,4,6,8-tetramethyl-cyclotetrasiloxane (D₄(AM)) in toluene using trifluoromethanesulfonic acid as a catalyst. Hexaethyldisiloxane was used as an end group to control the molecular weight of the polymer. The generated polymers had a consistency suitable for injection into the empty lens capsule. The polymers contained a low ratio of polymerisable groups so that, in the presence of a photo-initiator, they could be cured on demand in situ within 5 min under irradiation of blue light to form an intraocular lens within the lens capsule. All resulting polysiloxane soft gels had a low elastic modulus and thus should be able to restore accommodation. The pre-cure viscosity and post-cure modulus of the generated polysiloxanes were controlled by the end group and D₄(AM) concentrations respectively in the re-equilibration reactions. The refractive index could be precisely controlled by adjusting the aromatic ratio in the polymer to suit such application as an artificial lens. Lens stretching experiments with both human and non-human primate cadaver lenses of different ages refilled with polysiloxane polymers provided a significant increase in amplitude of accommodation (up to 4 D more than that of the respective natural lens). Both in vitro cytotoxicity study using L929 cell lines and in vivo biocompatibility study in rabbit models demonstrated the non-cytotoxicity and ocular biocompatibility of the polymer., (Crown Copyright © 2012. Published by Elsevier Ltd. All rights reserved.)

Micropatterning of surfaces with varying chemical, physical and topographical properties usually requires a number of fabrication steps. Herein, we describe a micropatterning technique based on plasma enhanced chemical vapour deposition (PECVD) that deposits both protein resistant and protein repellent surface chemistries in a single step. The resulting multifunctional, selective surface chemistries are capable of spatially controlled protein adhesion, geometric confinement of cells and the site specific confinement of enzyme mediated peptide self-assembly., (This journal is © The Royal Society of Chemistry 2012)

Objective: To evaluate 24-week virologic effectiveness of novel antiretroviral regimens for treatment of three-class experienced adult patients in a clinical practice setting following the US Food and Drug Administration approval of darunavir (DRV) for this population., Design: A prospective cohort study., Setting: A single-center, academic HIV clinic., Participants: Three-class antiretroviral-experienced patients changing regimens between July 2006 and May 2008. Sociodemographic, psychosocial, and clinical characteristics were collected at baseline and during prospective follow-up., Outcome Measures: Plasma HIV viral load below 50 copies/ml and change in CD4 cell count at 24 weeks following regimen change. The Stanford Genotype Database was used to analyze HIV genotype resistance results and determine the number of active drugs in each regimen. Multivariate models and propensity score methods were employed to assess outcome measures., Results: Among 109 three-class experienced patients, who previously received an average of 10.5 prior antiretrovirals, 55% achieved viral load below 50 copies/ml at 24 weeks. Treatment strategy was classified as nonprotease inhibitor (n = 25), DRV/ritonavir (DRV/r) (n = 51), or other protease inhibitor (n = 33). The number of active drugs was not significantly different across strategies (P = 0.24). In multivariate analysis, patients treated with DRV/r (65%, odds ratio = 4.24 vs. nonprotease inhibitor strategy, 95% confidence interval = 1.28-14.06), raltegravir (65%, odds ratio = 3.10, 95% confidence interval = 1.12-8.62), or both were more likely to achieve viral load below 50 copies/ml., Conclusion: Among antiretroviral-experienced patients changing regimens, those treated with DRV/r, raltegravir, or both were more likely to achieve a viral load below 50 copies/ml at 24 weeks. The effectiveness of these agents in routine clinical care mirrors their efficacy in clinical trials and has ushered in a new era in the therapy of three-class experienced patients.

Biocompatible coatings with suitable chemistries for the immobilization of biomolecules are increasingly in demand, as they can be applied in a wide range of biomedical applications. In particular, multifunctional polymer coatings displaying reactive functional groups for the immobilization of specific biological factors that can influence the cellular response while at the same time exhibiting low nonspecific protein adsorption and cell attachment properties have the potential to significantly advance the fields of biomaterials and regenerative medicine. In this study, multifunctional polymer surface chemistries were developed for a cell microarray application with the aim of screening cellular interactions with surface immobilized factors. Coatings were prepared by the deposition of an allylamine plasma polymer pinning layer followed by the deposition of random copolymers of glycidyl methacrylate (GMA) and poly(ethylene glycol) methacrylate (PEGMA). Coatings were characterized by X-ray photoelectron spectroscopy (XPS), infrared spectroscopy, ellipsometry, and contact angle measurements. A variety of proteins as well as synthetic polymers were printed onto copolymer-coated slides using a high-precision contact microarrayer. Printing conditions were optimized for a fluorescently labeled model protein in regard to the temperature, humidity, pin geometry, concentration, and pH of the printing solution. Finally, the suitability of the surface chemistry for the evaluation of cellular responses to surface immobilized factors in a microarray format was demonstrated using HeLa cells.

Corneal epithelial wounds heal rapidly by the inwards growth of tissue with a contracting wound front. A synthetic polymer lens to correct refractive error (an implantable contact lens) could be incorporated into the cornea using this wound healing process. Topographical cues on the polymer surface may facilitate epithelial tissue migration over the anterior device surface. Here, silicone discs with a defined surface geometry of parallel grooves (groove and ridge widths of 1, 2, 5 and 10 microm; groove depths of 1 and 5 microm) were implanted into corneas and maintained in organ culture. The nature and rate of epithelial tissue migration over the test surfaces was monitored for 8 days and evaluated using microscopy and histology. Irrespective of the pitch, deep groove geometries directed tissue migration laterally along the grooves but this prevented contraction of the wound front and retarded migration rates. No guidance occurred on any of the shallow groove geometries but these allowed inwards radial migration with a contracting wound front and supported migration rates equivalent to a flat surface. None of the geometries tested promoted tissue migration above a flat polymer surface and data suggested that parallel grooves may not be optimal for this application.

The current study sought to identify a collagen coating methodology for application to polymer surfaces that would provide for the development of adhesive structures responsible for the sustained adhesion of corneal epithelial tissue. We compared an uncoated microporous polycarbonate surface and equivalent surfaces coated with either covalently immobilized collagen I or chemically crosslinked collagen I gel in a corneal explant outgrowth assay over 21 days. Electron microscopy was used to examine the formation of hemidesmosomes, basal lamina, and anchoring fibrils at the tissue-polymer interface. The crosslinked collagen gel preparation supported the overlying epithelial tissue across the pore openings and allowed for the formation of identifiable basal lamina, hemidesmosomes, and anchoring fibrils between the epithelial tissue and the polymer surface. Hemidesmosomal plaque, but no basal lamina or anchoring fibril formation, occurred on the uncoated surface or on that coated with covalently immobilized collagen I. We propose that the collagen matrix provided by the crosslinked collagen gel was reorganized by the epithelial tissue and that this, combined with the secretion of ECM molecules, served to limit the diffusion of basement membrane components, which permitted an increase in the local concentration of these molecules, which favored the assembly of epithelial adhesive structures., (Copyright 2001 John Wiley & Sons, Inc. J Biomed Mater Res 56: 461--468, 2001)

A surface with columnar pores 0.1 or 0.4 microm in diameter is shown to have a novel effect on the migration of corneal epithelial tissue sheets; migration is stimulated in a nondirectional manner with respect to migration over a planar, nonporous surface (Dalton, Evans, McFarland, and Steele, J Biomed Mater Res 1999;45:384-394; Steele, Johnson, McLean, Beumer, and Griesser, J Biomed Mater Res 2000;50:475-482). By blind-ending the pores, we show that this increase in tissue migration is not dependent on fluid flux through the pores and so appears to occur as a result of surface topography. From transmission electron micrographs, the migrating tissue appears to form either close contacts or focal adhesions at the edge of some pore channels; we speculate that this may provide a fulcrum for the enhanced migration. Scanning electron micrographs suggest that within tissue that migrates over the surfaces that contain blind-ended pores, the cells are more extensively spread than those in tissue migrating on a planar surface. The migration of disaggregated epithelial cells is enhanced on surfaces that contain 0.1- or 0.4-microm-diameter pores (compared with a planar surface), and this is similarly independent of fluid flux.

The dipeptide L-carnosine has beneficial effects on cultured human fibroblasts. Physiological concentrations in standard media prolong their in vitro lifespan and strongly reduce the normal features of senescence. Late passage cells in normal medium are rejuvenated when transferred to medium containing carnosine, and become senescent when carnosine is removed. In the absence of pyruvate, carnosine is cytotoxic to neoplastic and transformed human and rodent cells. None of these effects are seen with its optical isomer, D-carnosine.

Melorheostosis is a rare, benign connective-tissue disorder characterized by a cortical thickening of bone with irregular dense hyperostosis that appears to flow along the cortex. We review the literature to date, etiology, clinical aspects, roentgenographic features, histology, and treatment of melorheostosis.

An anatomic study was outlined to measure the strength of the posterior cruciate ligament after total knee arthroplasty. This interest was precipitated by a patient whose posterior cruciate ligament ruptured 6 months after a total knee arthroplasty. Six unembalmed knee specimens (three bilateral) were mounted in a mechanical tension-testing machine, and proximal tibial total-knee bone cuts were performed at successive 2 to 3 mm depths. At each level, the ligament was tested at physiologic tension. The posterior cruciate ligament failed at 7 to 10 mm of bone resected, with an average failure at 8.6 mm.

We have studied the catalytic activity and some other properties of mutants of Escherichia coli plasmid-encoded RTEM beta-lactamase (EC 3.5.2.6) with all combinations of serine and threonine residues at the active-site positions 70 and 71. (All natural beta-lactamases have conserved serine-70 and threonine-71.) From the inactive double mutant Ser-70----Thr, Thr-71----Ser [Dalbadie-McFarland, G., Cohen, L. W., Riggs, A. D., Morin, C., Itakura, K., & Richards, J. H. (1982) Proc. Natl. Acad. Sci. U.S.A. 79, 6409-6413], an active revertant, Thr-71----Ser (i.e., residue 70 in the double mutant had changed from threonine to the serine conserved at position 70 in the wild-type enzyme), was isolated by an approach that allows identification of active revertants in the absence of a background of wild-type enzyme. This mutant (Thr-71----Ser) has about 15% of the catalytic activity of wild-type beta-lactamase. The other possible mutant involving serine and threonine residues at positions 70 and 71 (Ser-70----Thr) shows no catalytic activity. The primary nucleophiles of a serine or a cysteine residue [Sigal, I. S., Harwood, B. G., & Arentzen, R. (1982) Proc. Natl. Acad. Sci. U.S.A. 79, 7157-7160] at position 70 thus seem essential for enzymatic activity. Compared to wild-type enzyme, all three mutants show significantly reduced resistance to proteolysis; for the active revertant (Thr-71----Ser), we have also observed reduced thermal stability and reduced resistance to denaturation by urea.

The three RNA trinucleotides; ApApA, ApApG, and ApUpG, have been synthesized in sufficient quantity to obtain natural abundance 13C(1H)-NMR spectra at strand concentrations between 4 and 100 mM. Comparisons between 70 degrees C spectra of the three trimers and their consistuent dimers ApA, ApG, ApU, and UpG allow secure assignments to be made for most of the resonances. This paper describes the syntheses and 13C assignments of the oligomers.

Eight patients with culture-proven Mycobacterium marinum synovitis had synovial specimens with a remarkably similar histologic appearance. There was considerable synovial hyperplasia, and the synovium was thickened by a moderately intense lymphohistiocytic infiltrate, notably devoid of plasma cells. Fibrin covered some synovial surfaces. Giant cells were both of the Langerhans' and foreign body types. Granulomas were noncaseating but varied in frequency and degree of definition. Knowledge of this morphologic picture has proved to be useful in patient care.

Due to excellent soft tissue contrast and multiplanar imaging capability, MRI is assuming a major role in recognition, staging, and treatment planning of soft tissue and bone tumors. Direct sagittal, coronal, and axial images permit assessment of intraosseous and extraosseous extension of tumors and their relationship to the joints and neurovascular structures, and detection of "skip" lesions. MRI allows improved detection of recurrent tumors in the presence of non-ferromagnetic metallic implants as compared to CT. In the evaluation of soft tissue tumors, MRI is more sensitive than CT and allows differentiation among fat, muscle, tendon, bone, and vascular structures based on signal characteristics. Over a period of 18 months, 100 soft tissue masses and bone tumors were evaluated using MRI. Spin echo sequences with T1 and T2 weighted images were most valuable in differentiating normal and abnormal tissues. Calculated comparative measurements of relaxation times showed no reliable difference between benign and malignant tumors.

Coomassie Brilliant Blue G250 dissolved in dilute perchloric acid solution was used to stain protein bands in starge gels. The bands were visible within min, no destaining was required and the gels could be stored indefinitely.

Uniquely among class A beta-lactamases, the RTEM-1 and RTEM-2 enzymes contain a single disulfide bond between Cys 77 and Cys 123. To study the possible role of this naturally occurring disulfide in stabilizing RTEM-1 beta-lactamase and its mutants at residue 71, this bond was removed by introducing a Cys 77----Ser mutation. Both the wild-type enzyme and the single mutant Cys 77----Ser confer the same high levels of resistance to ampicillin in vivo to Escherichia coli; at 30 degrees C the specific activity of purified Cys 77----Ser mutant is also the same as that of the wild-type enzyme. Also, neither wild-type enzyme nor the Cys 77----Ser mutant is inactivated by brief exposure to p-hydroxymercuribenzoate. However, above 40 degrees C the mutant enzyme is less stable than wild-type enzyme. After introduction of the Cys 77----Ser mutation, none of the double mutants (containing the second mutations at residue 71) confer resistance to ampicillin in vivo at 37 degrees C; proteins with Ala, Val, Leu, Ile, Met, Pro, His, Cys, and Ser at residue 71 confer low levels of resistance to ampicillin in vivo at 30 degrees C. The use of electrophoretic blots stained with antibodies against beta-lactamase to analyze the relative quantities of mutant proteins in whole-cell extracts of E. coli suggests that all 19 of the doubly mutant enzymes are proteolyzed much more readily than their singly mutant analogues (at Thr 71) that contain a disulfide bond.(ABSTRACT TRUNCATED AT 250 WORDS)

This article presents data from a descriptive study, validating etiologies and defining characteristics for the nursing diagnosis of impaired communication. Implications for nursing research, practice, and education are discussed.

In four unusual cases where a low-grade chondrosarcoma suddenly dedifferentiated into a florid, highly-malignant fibrosarcoma, the average survival was 12 months (range 5-18 months). The surgical treatment of chondrosarcoma consists of a primary excisional biopsy, and if dedifferentiation to fibrosarcoma is seen, radical excision and chemotherapy or irradiation or both.

A rapid and highly reproducible chromatographic technique has been developed for analysis and purification of complex mixtures of oligoribonucleotides. The method utilizes a column of microparticulate porous silica beads fully derivatized with octadecylsilyl groups. The column is eluted with gradients in acetonitrile/water/ammonium acetate pumped at pressures of 1500-300 psi. Most separations are completed in 5-15 min. with usually better than 1% reproducibility of absolute retention times and about 0.1% reproducibility of relative retention times. A single column accomplishes separations of mononucleosides, mononucleotides, and larger oligomers through at least 20-mers. The absolute detection limit is approximately 1 pmole of base though most of the analytical separations described use approximately 1 nmole. In favorable circumstances it is possible to use the analytical colums to purify approximately 1 mg of an oligonucleotide in a single 10-30 min. elution.