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1.
J Cyst Fibros ; 18(4): 507-515, 2019 07.
Article in English | MEDLINE | ID: mdl-30477895

ABSTRACT

BACKGROUND: Biologic pathways and metabolic mechanisms underpinning early systemic disease in cystic fibrosis (CF) are poorly understood. The Baby Observational and Nutrition Study (BONUS) was a prospective multi-center study of infants with CF with a primary aim to examine the current state of nutrition in the first year of life. Its secondary aim was to prospectively explore concurrent nutritional, metabolic, respiratory, infectious, and inflammatory characteristics associated with early CF anthropometric measurements. We report here metabolomics differences within the urine of these infants as compared to infants without CF. METHODS: Urine metabolomics was performed for 85 infants with predefined clinical phenotypes at approximately one year of age enrolled in BONUS via Ultrahigh Performance Liquid Chromatography-Tandem Mass Spectroscopy (UPLC-MS/MS). Samples were stratified by disease status (non-CF controls (n = 22); CF (n = 63, All-CF)) and CF clinical phenotype: respiratory hospitalization (CF Resp, n = 22), low length (CF LL, n = 23), and low weight (CF LW, n = 15). RESULTS: Global urine metabolomics profiles in CF were heterogeneous, however there were distinct metabolic differences between the CF and non-CF groups. Top pathways altered in CF included tRNA charging and methionine degradation. ADCYAP1 and huntingtin were identified as predicted unique regulators of altered metabolic pathways in CF compared to non-CF. Infants with CF displayed alterations in metabolites associated with bile acid homeostasis, pentose sugars, and vitamins. CONCLUSIONS: Predicted metabolic pathways and regulators were identified in CF infants compared to non-CF, but metabolic profiles were unable to discriminate between CF phenotypes. Targeted metabolomics provides an opportunity for further understanding of early CF disease. TRIAL REGISTRATION: United States ClinicalTrials.Gov registry NCT01424696 (clinicaltrials.gov).


Subject(s)
Cystic Fibrosis/urine , Metabolomics , Cystic Fibrosis/complications , Cystic Fibrosis/metabolism , Female , Humans , Infant , Male , Metabolic Networks and Pathways , Nutritional Status , Prospective Studies
2.
Bull Environ Contam Toxicol ; 92(5): 503-8, 2014 May.
Article in English | MEDLINE | ID: mdl-24526283

ABSTRACT

The smallmouth buffalo Ictiobus bubalus is a native benthivore to floodplain lakes in the Yazoo River Basin, USA. Based on evidence from other benthivorous fish studies we hypothesized high biomasses of I. bubalus contribute to poor water quality conditions. We tested this hypothesis in shallow (<1.5 m) 0.05 ha earthen ponds at three stocking biomasses over a 10-week period during the summer of 2012. The most notable results from the permutational multivariate analysis of variance suggest I. bubalus at high and moderate biomasses significantly (p < 0.05) enhanced turbidity and suspended solid levels while decreasing Secchi depth. Our results suggest that effects of I. bubalus on water clarity may have considerable ecological implications in natural habitats such as shallow floodplain lakes.


Subject(s)
Cypriniformes/physiology , Water Pollutants, Chemical/analysis , Animals , Biomass , Cypriniformes/growth & development , Eutrophication , Nitrogen/analysis , Oxygen/analysis , Phosphorus/analysis , Population Growth , Water Quality
3.
Rev Sci Instrum ; 82(5): 053304, 2011 May.
Article in English | MEDLINE | ID: mdl-21639497

ABSTRACT

A compact electron cyclotron resonance proton source has been developed and installed recently at the Paul Scherrer Institute's high intensity proton accelerator. Operation at the ion source test stand and the accelerator demonstrates a high reliability and stability of the new source. When operated at a 10-12 mA net proton current the lifetime of the source exceeds 2000 h. The essential development steps towards the observed performance are described.

4.
Biochemistry ; 46(30): 8744-52, 2007 Jul 31.
Article in English | MEDLINE | ID: mdl-17605471

ABSTRACT

Severe acute respiratory syndrome (SARS) is an emerging infectious disease associated with a high rate of mortality. The SARS-associated coronavirus (SARS-CoV) has been identified as the etiological agent of the disease. Although public health procedures have been effective in combating the spread of SARS, concern remains about the possibility of a recurrence. Various approaches are being pursued for the development of efficacious therapeutics. One promising approach is to develop small molecule inhibitors of the essential major polyprotein processing protease 3Clpro. Here we report a complete description of the tetrapeptide substrate specificity of 3Clpro using fully degenerate peptide libraries consisting of all 160,000 possible naturally occurring tetrapeptides. The substrate specificity data show the expected P1-Gln P2-Leu specificity and elucidate a novel preference for P1-His containing substrates equal to the expected preference for P1-Gln. These data were then used to develop optimal substrates for a high-throughput screen of a 2000 compound small-molecule inhibitor library consisting of known cysteine protease inhibitor scaffolds. We also report the 1.8 A X-ray crystal structure of 3Clpro bound to an irreversible inhibitor. This inhibitor, an alpha,beta-epoxyketone, inhibits 3Clpro with a k3/Ki of 0.002 microM(-1) s(-1) in a mode consistent with the substrate specificity data. Finally, we report the successful rational improvement of this scaffold with second generation inhibitors. These data provide the foundation for a rational small-molecule inhibitor design effort based upon the inhibitor scaffold identified, the crystal structure of the complex, and a more complete understanding of P1-P4 substrate specificity.


Subject(s)
Antiviral Agents/isolation & purification , Antiviral Agents/pharmacology , Cysteine Proteinase Inhibitors/pharmacology , Dipeptides/pharmacology , Epoxy Compounds/pharmacology , Oligopeptides/pharmacology , Severe acute respiratory syndrome-related coronavirus/enzymology , Viral Proteins/antagonists & inhibitors , Amino Acid Substitution , Animals , Antiviral Agents/chemistry , Antiviral Agents/metabolism , Catalytic Domain/drug effects , Chlorocebus aethiops , Coronavirus 3C Proteases , Crystallography, X-Ray , Cysteine Endopeptidases/chemistry , Cysteine Proteinase Inhibitors/chemistry , Cysteine Proteinase Inhibitors/classification , Dipeptides/chemistry , Dipeptides/isolation & purification , Dipeptides/metabolism , Epoxy Compounds/chemistry , Epoxy Compounds/isolation & purification , Epoxy Compounds/metabolism , Models, Molecular , Oligopeptides/chemistry , Oligopeptides/isolation & purification , Oligopeptides/metabolism , Peptide Library , Protein Structure, Tertiary , Severe acute respiratory syndrome-related coronavirus/drug effects , Structure-Activity Relationship , Substrate Specificity , Vero Cells , Viral Proteins/chemistry , Virus Replication/drug effects
5.
J Bone Joint Surg Am ; 87(2): 280-5, 2005 Feb.
Article in English | MEDLINE | ID: mdl-15687148

ABSTRACT

We previously evaluated a cohort of fifty-three patients with severe hip dysplasia (Crowe Type-II, III, or IV subluxation) who underwent a total of sixty-six Charnley total hip arthroplasties. The acetabular component was placed at the anatomic hip center, the superolateral defect was filled with cement, and no bone-grafting was used to supplement the acetabular wall. All but one patient, who was lost to follow-up, were followed until death or for a minimum of twenty years. Radiographic and functional follow-up data were collected prospectively. This retrospective review included twenty-four patients (thirty-four hips) who were alive at a minimum of twenty years following the surgery. Fourteen (22%) of the sixty-five hips underwent revision of a component, with eleven of the revisions performed because of aseptic loosening. Eight of those eleven hips underwent revision because of acetabular loosening alone; two, because of femoral loosening alone; and one, because of loosening of both components. The combined prevalence of revision because of aseptic loosening of the acetabular component and radiographic evidence of failure of the acetabular component was 28% (eighteen hips). With the numbers available, the need for acetabular revision was not associated with the percentage of cement coverage (p = 0.362) or the Crowe classification (p = 0.159). At a minimum of twenty years postoperatively, the survivorship of the acetabular component was 86% +/- 8% with revision because of aseptic loosening as the end point and 82% +/- 10% with revision because of aseptic loosening or radiographic evidence of loosening as the end point. The results that we evaluated at a minimum of twenty years after use of this technique can be compared with the results of other techniques in studies with similar long-term follow-up periods.


Subject(s)
Arthroplasty, Replacement, Hip , Cementation , Hip Dislocation/surgery , Adult , Aged , Aged, 80 and over , Female , Follow-Up Studies , Hip Dislocation/diagnostic imaging , Humans , Male , Middle Aged , Prosthesis Failure , Radiography , Recovery of Function , Reoperation , Retrospective Studies , Severity of Illness Index , Time Factors , Treatment Outcome
6.
Water Sci Technol ; 48(5): 9-14, 2003.
Article in English | MEDLINE | ID: mdl-14621142

ABSTRACT

The infiltration rate and therefore the principal function of a sand based vertical flow constructed wetland (VFCW) is influenced by the content of suspended solids (SS) and chemical oxygen demand (COD) of the waste water supply. In this study there were three operating conditions defined as "No Clogging"; "Partly Clogging" and "Clogging". Investigations on 21 VFCWs approved analytical differences between these conditions. The content of SS and especially particles > 50 microm are considered to play a key role. These particles are of the same size as the pores in which seepage mainly occurs. Thus their potential for surface blocking is high. It is concluded that the construction and size of the primary settling has to ensure that the mean concentration of SS after settling does not exceed 100 mg l(-1). The results of this study indicate that the area of the VFCW should be designed for a maximum loading rate of 5 g m(-2) d(-1) and the COD load should not exceed 20 g m(-2) d(-1).


Subject(s)
Sewage/chemistry , Waste Disposal, Fluid/methods , Water Movements , Biodegradation, Environmental , Ecosystem , Filtration , Oxygen/chemistry , Particle Size
7.
J Arthroplasty ; 16(8 Suppl 1): 195-202, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11742475

ABSTRACT

The current study evaluates the 4- to 8-year results of 26 cemented femoral revisions with impaction allografting using a collared femoral component in cases of extensive femoral bone loss. Patients were followed prospectively and were evaluated at an average of 6.0 years after the allograft revision procedure. The average age at the time of surgery was 69.3 years. At final follow-up, 20 patients (20 hips) were living, and 6 patients (6 hips) were deceased. No femoral component rerevisions were performed for any reason in any patient, and none were radiographically loose at final follow-up. There was 1 subsided femoral component of <5 mm, 3 postoperative periprosthetic femoral fractures, and a greater trochanter nonunion rate of 32%. At the current follow-up interval, these cemented femoral revisions with impaction allografting have performed well with excellent clinical and radiographic durability in this difficult patient population. The prevalence of periprosthetic fracture is a significant concern. This study shows durable results using the impaction allografting technique in cases of severe bone loss.


Subject(s)
Arthroplasty, Replacement, Hip , Bone Transplantation/methods , Femur/pathology , Hip Prosthesis , Aged , Aged, 80 and over , Cementation , Female , Femur/surgery , Follow-Up Studies , Hip Joint/diagnostic imaging , Hip Joint/surgery , Humans , Male , Middle Aged , Prosthesis Failure , Radiography , Reoperation , Transplantation, Homologous , Treatment Outcome
8.
J Bone Joint Surg Am ; 83(12): 1840-8, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11741064

ABSTRACT

BACKGROUND: In total hip arthroplasty, techniques for cementing the femoral component have changed over time. The purpose of the present study was to determine whether a cementing technique that includes use of a distal cement plug and retrograde filling of the femoral canal affects the fixation of the femoral component at a minimum of twenty years after the operation. METHODS: Between 1976 and 1978, the senior one of us (R.C.J.) performed 357 total hip arthroplasties with use of a Charnley flatback polished femoral stem and a contemporary cementing technique (insertion of a distal cement plug and retrograde filling of the femoral canal with cement) in 320 patients. The results after a minimum follow-up of twenty years were compared with those after 330 total hip arthroplasties performed, between 1970 and 1972, with the same femoral stem by the same surgeon with use of a hand-packing technique of cementing in 262 patients. The clinical and radiographic evaluation as well as the duration of follow-up were identical in the two groups. RESULTS: In the group managed with the contemporary cementing technique, six (1.8%) of the 336 hips that had not been lost to follow-up or revised because of infection or dislocation were revised because of aseptic loosening of the femoral component. Of the ninety-one hips in the eighty-two patients who were alive at a minimum of twenty years, five (5%) had a revision because of aseptic loosening of the femoral component. Only one hip was revised during the fifteen-to-twenty-year follow-up interval. (The revision was performed because of a fracture of the femoral component.) The rate of failure when radiographic signs of loosening were included was 4.8% (sixteen of 336 femoral components that had not been revised because of infection or dislocation) for the group managed with the contemporary cementing technique compared with 6.3% (twenty of 319 hips) in the group managed with the hand-packing technique; the difference was not significant (p = 0.40). Adequate filling of the femoral canal with cement was found to be associated with improved survival of the femoral component (p = 0.03). CONCLUSIONS: While no significant difference between the two cementing techniques could be identified, the ability to deliver adequate cement around the femoral component was more predictable with the contemporary cementing technique. In addition, the prevalence of loosening of the femoral component was low with use of either technique, a tribute to the Charnley flatback polished femoral component design.


Subject(s)
Arthroplasty, Replacement, Hip/methods , Bone Cements , Adult , Aged , Aged, 80 and over , Case-Control Studies , Female , Follow-Up Studies , Humans , Male , Middle Aged , Osteolysis/epidemiology , Patient Satisfaction , Prosthesis Failure , Reoperation/statistics & numerical data , Statistics, Nonparametric , Survival Analysis
9.
J Bone Joint Surg Am ; 83(11): 1706-11, 2001 Nov.
Article in English | MEDLINE | ID: mdl-11701795

ABSTRACT

BACKGROUND: Although cementless acetabular components are routinely used in revision hip surgery, few investigators have evaluated the retention and efficacy of these components in the long term. In the current study, the clinical and radiographic outcomes of a series of arthroplasties performed by one surgeon with a cementless acetabular component were assessed at a minimum of ten years. METHODS: From 1986 through 1988, sixty-one consecutive revision total hip arthroplasties were performed in fifty-five patients because of aseptic failure of one or both components of a prosthesis in which both components had been cemented. Twenty-eight patients (thirty-two hips) were alive at a mean of 12.9 years (range, 11.5 to 14.3 years) after the operation. In all of the patients, the acetabular component was revised to a porous-coated Harris-Galante component inserted without cement, and the femoral component was revised to an Iowa component affixed with contemporary cementing techniques. The hips were evaluated clinically and radiographically at a minimum of ten years subsequent to the index revision. No hips were lost to follow-up. RESULTS: None of the acetabular components required revision because of aseptic loosening. Two hips (3%) demonstrated radiographic evidence of aseptic loosening of the acetabular component. The polyethylene liner was exchanged during the follow-up period in eight hips. CONCLUSION: After a minimum of ten years of follow-up, cementless acetabular fixation in revision hip arthroplasty had produced durable results that were markedly better than those reported for acetabular fixation with cement.


Subject(s)
Acetabulum , Arthroplasty, Replacement, Hip/methods , Hip Prosthesis , Adult , Aged , Arthroplasty, Replacement, Hip/instrumentation , Cementation , Female , Follow-Up Studies , Humans , Male , Middle Aged , Prosthesis Failure , Reoperation , Statistics, Nonparametric , Survival Analysis , Treatment Outcome
10.
Microcirculation ; 8(5): 355-64, 2001 Oct.
Article in English | MEDLINE | ID: mdl-11687947

ABSTRACT

OBJECTIVE: Upregulation of adhesion molecules on endothelial cells following irradiation has been shown, but the functional significance of this upregulation in various endothelial cell lines is not clear. We have developed an in vitro flow model to study the functional consequences of the radiation-induced upregulation of E-selectin and intercellular adhesion molecule (ICAM-1). METHODS: Human dermal microvascular endothelial cells (HDMEC), human umbilical vein endothelial cells (HUVEC), or transformed human microvascular endothelial cells (HMEC-1) were grown in 35-mm dishes and irradiated with a single dose of 10 Gy. HL-60 (human promyelocytic leukemia) cells were perfused over the irradiated endothelial cells in a parallel plate flow chamber at shear stress ranging from 0.5 to 2.0 dynes/cm2. Flow cytometry was used to quantify the expression of E-selectin and ICAM-1 on the various endothelial cells. RESULTS: Flow cytomeric analysis revealed an upregulation of ICAM-1 expression on all three cell types postirradiation (post-IR), and an upregulation of E-selectin expression only on HDMEC post-IR. E-selectin expression was detected on control HDMEC, but at a lower level than that detected on post-IR HDMEC. Flow assays revealed a significant increase in the number of rolling and firmly adherent HL-60 cells on post-IR HDMEC at shear stress < or =1.5 dynes/cm2; pretreatment of control and irradiated HDMEC with antibodies to E-selectin and ICAM-1 significantly diminished the number of rolling and firmly adherent HL-60 cells, respectively. No rolling or firm adhesion of HL-60 cells was observed on HUVEC or HMEC-1 monolayers post-IR. CONCLUSION: These findings suggest that ICAM-1 is upregulated on irradiated HDMEC, HUVEC, and HMEC-1. E-selectin is upregulated to a functional level only on irradiated HDMEC, and not on irradiated HUVEC or HMEC-1.


Subject(s)
Cell Adhesion Molecules/biosynthesis , Endothelium, Vascular/metabolism , Up-Regulation/radiation effects , Cell Adhesion/drug effects , Cell Adhesion Molecules/pharmacology , Cell Adhesion Molecules/physiology , Cells, Cultured , E-Selectin/biosynthesis , E-Selectin/pharmacology , E-Selectin/physiology , Endothelium, Vascular/cytology , Endothelium, Vascular/radiation effects , Flow Cytometry , HL-60 Cells , Humans , Intercellular Adhesion Molecule-1/biosynthesis , Intercellular Adhesion Molecule-1/pharmacology , Intercellular Adhesion Molecule-1/physiology , Leukocytes/cytology , Microcirculation , Perfusion , Radiation, Ionizing , Skin/blood supply , Stress, Mechanical , Umbilical Cord/cytology
11.
Orthop Clin North Am ; 32(4): 587-91, viii, 2001 Oct.
Article in English | MEDLINE | ID: mdl-11689372

ABSTRACT

The purpose of this article is to evaluate the dislocations that occurred in a single surgeon practice over a 26 year period. After extensive research, the authors concluded that dislocation continues to occur long after the initial arthroplasty procedure. Patients should be aware that more than a quarter of dislocations occur 2 years following surgery. Use of modular 22 millimeter components were associated with the highest dislocation rate. These components should be used very cautiously. Constrained liners have helped decrease the dislocation rate following revision for dislocation.


Subject(s)
Arthroplasty, Replacement, Hip , Hip Dislocation/etiology , Postoperative Complications , Aged , Humans , Recurrence , Reoperation , Retrospective Studies , Time Factors
12.
Psychol Med ; 31(6): 1025-35, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11513370

ABSTRACT

BACKGROUND: The clinician-administered version of the Liebowitz Social Anxiety Scale (LSAS-CA) is a commonly used assessment device for the evaluation of social anxiety disorder and has been shown to have strong psychometric characteristics. Because of its apparently straightforward rating format and potential savings in time and effort, interest in the use of the LSAS as a self-report (LSAS-SR) measure has increased, and the LSAS-SR has been used in a number of studies. However, the psychometric properties of the LSAS-SR have not been well established. METHODS: This study examined the psychometric properties of the LSAS-SR in comparison to the LSAS-CA in a sample of 99 individuals with a primary diagnosis of social anxiety disorder and 53 individuals with no current psychiatric disorder. RESULTS: There was little difference between the two versions of the LSAS on any scale or subscale score. Both forms were internally consistent and the subscale intercorrelations for the two forms were essentially identical. Correlations of each LSAS-SR index with its LSAS-CA counterpart were all highly significant. Finally, the convergent and discriminant validity of the two forms of the LSAS was shown to be strong. CONCLUSION: Results of this study suggest that the self-report version of the LSAS compares well to the clinician-administered version and may be validly employed in the assessment of social anxiety disorder.


Subject(s)
Anxiety Disorders/diagnosis , Self-Assessment , Surveys and Questionnaires , Adult , Depression/diagnosis , Female , Humans , Male , Phobic Disorders/diagnosis , Psychiatric Status Rating Scales , Psychometrics , Random Allocation , Reproducibility of Results
13.
Ann Biomed Eng ; 29(6): 523-33, 2001 Jun.
Article in English | MEDLINE | ID: mdl-11459346

ABSTRACT

The heterogeneous distribution of endothelial cell adhesion molecules (ECAMs) on the lumenal surface of vascular endothelium provides an opportunity to deliver drugs to select tissues. The targeting could be achieved by using carriers whose outer surface has a ligand for a selectively expressed ECAM. The carriers would interact with the endothelium in a fluid dynamic environment and in many of these schemes nanoparticles would be used. It is unclear what role various parameters (e.g., ligand-ECAM chemistry, fluid shear) will have on the adhesion of the nanoparticles to the endothelium. To facilitate studies in this area, we have developed a prototypical in vitro model that allows investigation of nanoparticle adhesion. We coated polystyrene nanospheres with a humanized mAb (HuEP5C7.g2) that recognizes the ECAMs E- and P-selectin. Adhesion assays revealed that HuEP5C7.g2 nanospheres exhibit augmented, specific adhesion to selectin presenting cellular monolayers and that the adhesion can be affected by the fluid shear. These results; (i) strongly suggest that HuEP5C7.g2 could be used to target nanoparticles to selectin presenting endothelium; (ii) demonstrate that fluid shear can affect nanoparticle adhesion; and (iii) define a system which can be used to study the effects of various system parameters on nanoparticle adhesion.


Subject(s)
E-Selectin/metabolism , P-Selectin/metabolism , Adhesiveness , Animals , Antibodies, Monoclonal/metabolism , Biomedical Engineering , CHO Cells , Cells, Cultured , Cricetinae , E-Selectin/immunology , Endothelium, Vascular/drug effects , Endothelium, Vascular/metabolism , Humans , Interleukin-1/pharmacology , Ligands , Mice , Microspheres , P-Selectin/immunology , Rheology
14.
Depress Anxiety ; 13(3): 118-24, 2001.
Article in English | MEDLINE | ID: mdl-11387731

ABSTRACT

The efficacy and tolerability of nefazodone in the treatment of major depression among Spanish-monolingual Hispanics was examined and compared to historical controls among English-speaking, predominantly non-Hispanic subjects. Fifty monolingual Hispanic outpatients with major depression and a HAM-D17 score > or = 18 were treated with nefazodone in a flexible-dose 8-week open-label protocol. Sixty-three percent of the intent-to-treat (ITT) sample with > or = 1 efficacy visit were considered responders according to CGI-I criteria, falling within the range of response rates (58-69%) reported in six prior nefazodone trials with non-Hispanic subjects. Significant improvement was found for the ITT and completer samples in HAM-D17, HAM-D28, and SCL-90 scores and in two measures of psychosocial functioning. Endpoint mean dose in the ITT sample was 379 mg/day (SD = 170), also within the range of previous trials (321-472 mg/day). Adverse effects were not elevated, with only dry mouth (8%) reported by > 6% of subjects. However, 42% of the sample dropped out of treatment before study termination, usually because of side effects or due to family or work difficulties, a higher rate than previously reported for nefazodone (21-33%). This open trial finds nefazodone to be an efficacious treatment for major depression among monolingual Hispanics, with comparable efficacy to previous controlled trials among non-Hispanic subjects. Double-blind studies are required to confirm this comparable efficacy. Mean endpoint doses and adverse effect rates similar to previous trials do not support the need for reduced doses of nefazodone among Hispanics. However, an elevated rate of treatment discontinuation threatens treatment efficacy among this population. Causes for this elevated rate require explanation, given the apparently unremarkable pattern of adverse effect reports.


Subject(s)
Antidepressive Agents, Second-Generation/therapeutic use , Depressive Disorder, Major/drug therapy , Hispanic or Latino/statistics & numerical data , Triazoles/therapeutic use , Adult , Depressive Disorder, Major/ethnology , Female , Hispanic or Latino/psychology , Humans , Male , Middle Aged , Patient Compliance , Patient Dropouts/statistics & numerical data , Piperazines , Psychiatric Status Rating Scales , Treatment Outcome
15.
Biotechnol Bioeng ; 73(6): 500-9, 2001 Jun 20.
Article in English | MEDLINE | ID: mdl-11344455

ABSTRACT

In a variety of disease settings the expression of the endothelial selectins E- and P-selectin appears to be increased. This feature makes these molecules attractive targets around which to design directed drug-delivery schemes. One possible approach for achieving such delivery is to use polymeric biodegradable microspheres bearing a humanized monoclonal antibody (MAb) for E- and P-selectin, MAb HuEP5C7.g2. Perhaps the simplest technique for "coupling" HuEP5C7.g2 to the microspheres is via nonspecific adsorption. Previous studies suggest, however, that the adsorption of proteins onto microspheres fabricated in the presence of a stabilizer such as poly(vinyl alcohol) (PVA) is limited. It is unclear to what extent this limited level of adsorbed HuEP5C7.g2 would be able to support adhesion to E- and P-selectin under flow conditions. To explore this issue, we prepared microspheres from the biodegradable polymer, poly(epsilon-caprolactone) (PCL), using a single emulsion process and PVA as a stabilizer. We then incubated the PCL microspheres with HuEP5C7.g2 and studied the adhesion of the resulting HuEP5C7.g2 microspheres to E- and P-selectin under in vitro flow conditions. We found that the HuEP5C7.g2 PCL microspheres exhibit specific adhesion to Chinese hamster ovary cells stably expressing P-selectin (CHO-P) and 4-h IL-1beta-activated human umbilical vein endothelial cells (HUVEC). In contrast, HuEP5C7.g2 PCL microspheres exhibit little adhesion to parental CHO cells or unactivated HUVEC. The attachment efficiency to the selectin substrates was quite low, with appreciable attachment occurring only at low shear (0.3 dyn/cm(2)). Other supporting data strongly suggest that the limited attachment efficiency is due to a low level of HuEP5C7.g2 adsorbed to the PCL microspheres. Although the attachment was limited, a significant percentage of the HuEP5C7.g2 PCL microspheres were able to remain adherent at relatively high shear (8 dyn/cm(2)). Combined, our data suggest that HuEP5C7.g2 PCL microspheres exhibit selective limited adhesion to cellular substrate expressing E- and P-selectin.


Subject(s)
Antibodies, Monoclonal/chemistry , E-Selectin/metabolism , Materials Testing , Microspheres , P-Selectin/metabolism , Adsorption , Animals , Antibodies, Monoclonal/metabolism , CHO Cells , Cells, Cultured , Cricetinae , E-Selectin/genetics , E-Selectin/immunology , Humans , Interleukin-1/pharmacology , P-Selectin/genetics , P-Selectin/immunology , Polyesters/chemistry , Polystyrenes , Umbilical Veins/cytology , Umbilical Veins/drug effects , Umbilical Veins/metabolism
16.
Biophys J ; 80(4): 1733-43, 2001 Apr.
Article in English | MEDLINE | ID: mdl-11259287

ABSTRACT

The diameter of circulating cells that may adhere to the vascular endothelium spans an order of magnitude from approximately 2 microm (e.g., platelets) to approximately 20 microm (e.g., a metastatic cell). Although mathematical models indicate that the adhesion exhibited by a cell will be a function of cell diameter, there have been few experimental investigations into the role of cell diameter in adhesion. Thus, in this study, we coated 5-, 10-, 15-, and 20-microm-diameter microspheres with the recombinant P-selectin glycoprotein ligand-1 construct 19.ek.Fc. We compared the adhesion of the 19.ek.Fc microspheres to P-selectin under in vitro flow conditions. We found that 1) at relatively high shear, the rate of attachment of the 19.ek.Fc microspheres decreased with increasing microsphere diameter whereas, at a lower shear, the rate of attachment was not affected by the microsphere diameter; 2) the shear stress required to set in motion a firmly adherent 19.ek.Fc microsphere decreased with increasing microsphere diameter; and 3) the rolling velocity of the 19.ek.Fc microspheres increased with increasing microsphere diameter. These results suggest that attachment, rolling, and firm adhesion are functions of particle diameter and provide experimental proof for theoretical models that indicate a role for cell diameter in adhesion.


Subject(s)
Cell Adhesion , Endothelium, Vascular/cytology , Animals , Antibodies, Monoclonal/metabolism , Endothelium, Vascular/metabolism , Humans , Immunoglobulin G/metabolism , Ligands , Mice , Microspheres , Models, Theoretical , P-Selectin/metabolism , Recombinant Proteins/metabolism , Stress, Mechanical
18.
Clin Orthop Relat Res ; (393): 157-62, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11764345

ABSTRACT

Regarding dislocation after total hip arthroplasty, prevention is worth an ounce of cure. The current authors evaluated dislocation after total hip arthroplasty during the 26-year practice of one surgeon to identify potential variables that can contribute to the prevention of dislocation. Between 1970 and 1996, dislocation after total hip replacement occurred after 7.2% of primary hip arthroplasty procedures (298 of 4164 primary hip replacements) and 11.2% of revision hip arthroplasty procedures (90 of 803 revision hip replacements). Significant findings included an increase in dislocation when 22-mm modular femoral heads were used and a decrease in dislocation after revision for dislocation when constrained liners were used. An additional finding was that 26% of first time dislocations occurred more than 2 years after surgery. Concerning prevention of dislocation, small head modular femoral components should be used cautiously, and constrained liners should be considered in complex revision cases. Patients should be counseled concerning the potential for dislocation many years after their arthroplasty.


Subject(s)
Arthroplasty, Replacement, Hip/adverse effects , Hip Dislocation/prevention & control , Aged , Female , Follow-Up Studies , Hip Dislocation/etiology , Humans , Male , Osteoarthritis, Hip/surgery , Reoperation
19.
J Allergy Clin Immunol ; 106(5): 840-3, 2000 Nov.
Article in English | MEDLINE | ID: mdl-11080704

ABSTRACT

BACKGROUND: The recent World Health Organization position paper on allergen immunotherapy states that local reactions to immunotherapy are not predictive of subsequent systemic reactions. Nevertheless, in clinical practice dose adjustment after local reactions continues to be recommended, presumably in an effort to prevent future systemic reactions. OBJECTIVE: We sought to determine whether dose adjustment versus no adjustment for local reactions during allergen immunotherapy influences the occurrence of subsequent systemic reactions. METHODS: In a single-site allergy clinic before October 1, 1997, local reactions after allergen vaccine injection resulted in adjustment of the subsequent dose. After October 1, 1997, no dose adjustments were made for immediate and late local reactions. For the same 9-month period before and after the change in local reaction dose-adjustment policy, systemic reaction rates were compared retrospectively. For individuals experiencing a systemic reaction, local reaction rates and local reactions immediately preceding a systemic reaction were also compared before and after the policy change. RESULTS: Comparing the 9-month period (October 1996-June 1997) preceding the policy change and the 9 months (October 1997-June 1998) after the change in policy, the systemic reaction rates (0.80% and 1.01%, respectively) were not statistically different (P =.24). Among those experiencing a systemic reaction, the rate of local reactions was unchanged (7.3% and 4.7%, respectively; P =.07), and the rate of local reactions immediately preceding a systemic reaction did not increase (18.8% and 10.5%, respectively; P =.37). The sensitivity of a local reaction predicting a systemic reaction at the next immunotherapy dose was 15%. CONCLUSIONS: A local reaction is a very insensitive predictor for a subsequent systemic reaction at the next allergen vaccine dose. Dose adjustment for most local reactions is unnecessary and may delay therapy, increase costs, and put the patient at increased risk of dose administration errors.


Subject(s)
Allergens/immunology , Desensitization, Immunologic , Adult , Dose-Response Relationship, Drug , Humans , Retrospective Studies
20.
J Trauma Stress ; 13(3): 529-34, 2000 Jul.
Article in English | MEDLINE | ID: mdl-10948492

ABSTRACT

OBJECTIVE: Ataque de nervios is a common, self-labeled Hispanic folk diagnosis. It typically describes episodic, dramatic outbursts of negative emotion in response to a stressor, sometimes involving destructive behavior. Dissociation and affective dysregulation during such episodes suggested a link to childhood trauma. We therefore assessed psychiatric diagnoses, history of ataque, and childhood trauma in treatment-seeking Hispanic outpatients (N = 70). Significantly more subjects with an anxiety or affective disorder plus ataque reported a history of physical abuse, sexual abuse, and/or or a substance-abusing caretaker than those with psychiatric disorder but no ataque. In some Hispanic individuals, ataque may represent a culturally sanctioned expression of extreme affect dysregulation associated with childhood trauma. Patients with ataque de nervios should receive a thorough traumatic history assessment.


Subject(s)
Child Abuse/psychology , Dissociative Disorders/ethnology , Hispanic or Latino/psychology , Mood Disorders/ethnology , Self-Injurious Behavior/ethnology , Adult , Anxiety , Caregivers , Child , Cultural Characteristics , Dissociative Disorders/psychology , Female , Humans , Male , Mood Disorders/psychology , Self-Injurious Behavior/psychology , Substance-Related Disorders
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