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1.
Diabetes Spectr ; 34(4): 345-356, 2021 Nov.
Article in English | MEDLINE | ID: mdl-34866867

ABSTRACT

Young adults with diabetes assume increasing responsibility for communicating with their health care providers, and engaging in high-quality health communication is an integral component of overall diabetes self-management. This article provides an overview of the main features of health communication, factors that may influence communication quality, interventions to promote communication skills, and practical strategies for clinicians working with young adults with diabetes. The review concludes with a comprehensive summary of future directions for health communication research.

2.
J Heart Lung Transplant ; 40(12): 1550-1559, 2021 12.
Article in English | MEDLINE | ID: mdl-34598871

ABSTRACT

BACKGROUND: Freedom from rejection in pediatric heart transplant recipients is highly variable across centers. This study aimed to assess the center variation in methods used to diagnose rejection in the first-year post-transplant and determine the impact of this variation on patient outcomes. METHODS: The PHTS registry was queried for all rejection episodes in the first-year post-transplant (2010-2019). The primary method for rejection diagnosis was determined for each event as surveillance biopsy, echo diagnosis, or clinical. The percentage of first-year rejection events diagnosed by surveillance biopsy was used to approximate the surveillance strategy across centers. Methods of rejection diagnosis were described and patient outcomes were assessed based on surveillance biopsy utilization among centers. RESULTS: A total of 3985 patients from 56 centers were included. Of this group, 873 (22%) developed rejection within the first-year post-transplant. Surveillance biopsy was the most common method of rejection diagnosis (71.7%), but practices were highly variable across centers. The majority (73.6%) of first rejection events occurred within 3-months of transplantation. Diagnosis modality in the first-year was not independently associated with freedom from rejection, freedom from rejection with hemodynamic compromise, or overall graft survival. CONCLUSIONS: Rejection in the first-year after pediatric heart transplant occurs in 22% of patients and most commonly in the first 3 months post-transplant. Significant variation exists across centers in the methods used to diagnose rejection in pediatric heart transplant recipients, however, these variable strategies are not independently associated with freedom from rejection, rejection with hemodynamic compromise, or overall graft survival.


Subject(s)
Graft Rejection/diagnosis , Heart Transplantation/adverse effects , Practice Patterns, Physicians' , Adolescent , Age Factors , Child , Female , Graft Rejection/etiology , Humans , Male , Registries , Retrospective Studies , Risk Factors , Time Factors
3.
J Heart Lung Transplant ; 40(5): 368-376, 2021 05.
Article in English | MEDLINE | ID: mdl-33642140

ABSTRACT

BACKGROUND: The size of the Fontan population with end-stage heart failure is growing. In this population, heart transplantation has been the only option. This study sought to investigate the efficacy of ventricular assist device (VAD) support in Fontan patients. METHODS: We conducted a retrospective study of Fontan patients in the Advanced Cardiac Therapies Improving Outcomes Network. We evaluated patient characteristics, and the clinical and physiologic outcomes after VAD implantation. RESULTS: We identified 45 Fontan patients implanted with VAD. The average age of patients was 10 years (interquartile range: 4.5-18) and 30% were female. The majority had a morphologic right ventricle (69%), moderate or greater ventricular dysfunction (83%), and moderate or greater atrioventricular valve regurgitation (65%). The majority of implants were as a bridge to transplantation (76%), and the majority of patients were Interagency Registry for Mechanically Assisted Circulatory Support Profile 2 (56%). The most commonly employed device was the Medtronic HeartWare HVAD (56%). A total of 13 patients were discharged on device support, and 67% of patients experienced adverse events, the most common of which were neurologic (25%). At 1 year after device implantation, the rate of transplantation was 69.5%, 9.2% of patients continued to be VAD supported, and 21.3% of patients had died. Hemodynamically, VAD was effective in decreasing both Fontan and ventricular end-diastolic pressures in some individuals. CONCLUSIONS: VAD is effective in supporting patients with end-stage Fontan failure awaiting heart transplantation. Future research should focus on identifying clinical and physiologic characteristics predictive of a favorable response to VAD support.


Subject(s)
Fontan Procedure , Heart Failure/surgery , Heart-Assist Devices , Registries , Adolescent , Child , Child, Preschool , Female , Follow-Up Studies , Heart Transplantation , Humans , Male , Retrospective Studies , Treatment Outcome
4.
J Adolesc ; 81: 61-72, 2020 06.
Article in English | MEDLINE | ID: mdl-32361462

ABSTRACT

INTRODUCTION: Early life adversity (ELA) can result in negative behavioral outcomes, including internalizing and externalizing problems. Evidence suggests that adolescence is a critical developmental period for processing ELA. Identity formation, which is crucial to this developmental period, may moderate the effect between ELA and these problems. One potential moderating variable associated with identity formation is the latent construct Prospective Self, comprised of future-oriented attitudes and behaviors. METHODS: Participants are from the first wave of an ongoing longitudinal study designed to characterize behavioral and cognitive correlates of risk behavior trajectories. A community sample of 10th and 12th grade adolescents (N = 2017, 55% female) were recruited from nine public school districts across eight Southeastern Michigan counties in the United States. Data were collected in schools during school hours or after school via self-report, computer-administered surveys. Structural equation modeling was utilized to assess Prospective Self as a latent construct and to evaluate the relationship between ELA, internalizing and externalizing problems, and Prospective Self. RESULTS: Preliminary findings indicated a satisfactory fit for the construct Prospective Self. The predicted negative associations between Prospective Self and internalizing and externalizing problems were found and evidence of moderation was observed for externalizing problems, such that the effects of ELA (i.e., childhood maltreatment) on externalizing problems were lower for individuals with higher levels of Prospective Self. CONCLUSIONS: These results indicate that Prospective Self may play a role in supporting resilience against externalizing problems associated with ELA among adolescents.


Subject(s)
Adolescent Behavior/psychology , Adverse Childhood Experiences/psychology , Internal-External Control , Resilience, Psychological , Adolescent , Female , Humans , Longitudinal Studies , Male , Michigan , Surveys and Questionnaires
5.
Biol Psychol ; 136: 87-99, 2018 07.
Article in English | MEDLINE | ID: mdl-29802861

ABSTRACT

We investigated central fatigue in 50 patients with chronic fatigue syndrome (CFS) and 50 matched healthy controls (HC). Resting state EEG was collected from 19 scalp locations during a 3 min, eyes-closed condition. Current densities were localized using exact low-resolution electromagnetic tomography (eLORETA). The Multidimensional Fatigue Inventory (MFI-20) and the Fatigue Severity Scale (FSS) were administered to all participants. Independent t-tests and linear regression analyses were used to evaluate group differences in current densities, followed by statistical non-parametric mapping (SnPM) correction procedures. Significant differences were found in the delta (1-3 Hz) and beta-2 (19-21 Hz) frequency bands. Delta sources were found predominately in the frontal lobe, while beta-2 sources were found in the medial and superior parietal lobe. Left-lateralized, frontal delta sources were associated with a clinical reduction in motivation. The implications of abnormal cortical sources in patients with CFS are discussed.


Subject(s)
Central Nervous System/physiopathology , Cerebral Cortex/physiopathology , Electroencephalography , Fatigue Syndrome, Chronic/physiopathology , Adult , Aged , Beta Rhythm , Brain Mapping , Delta Rhythm , Female , Frontal Lobe/physiopathology , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Motivation , Parietal Lobe/physiopathology , Rest , Tomography
6.
Mater Sci Eng C Mater Biol Appl ; 33(7): 4352-60, 2013 Oct.
Article in English | MEDLINE | ID: mdl-23910353

ABSTRACT

Biodegradable materials, which are currently available for bone tissue regeneration, still have limitations regarding their degradation rate, mechanical stability and/or biological response. Thus, a novel generation of materials for bioactive bone scaffolds is needed that triggers hydroxyapatite formation and can be tailored to suit application-specific requirements. In this study we developed ternary bioactive composite materials composed of poly(3-hydroxybutyrate-co-3-hydroxyvalerate), calcium silicate and poly(lactide-co-glycolide) (PHBV/CS/PLGA), which merged the good bioactivity of CS/PHBV composite and the improved degradation velocity of PHBV/PLGA blend. Bioactive character of all composites was proven by formation of hydroxyapatite-like crystals after already one week of incubation in simulated body fluid. Addition of PLGA significantly increased initial ultimate tensile strength (UTS0) and Young's modulus of the ternary composites from 14.3±1.1 MPa (binary composite) to 22.3±2.6 MPa and 1.23±0.05 GPa up to 1.64±0.14 GPa, respectively. Furthermore the degradation rate (measured as a decrease of UTS during degradation) could be successfully tailored and was in range of -0.033 UTS0 to -0.118 UTS0 MPa/week. The bioacceptance of the materials was proven in vitro using 2-D (conventional setup) and 3-D (multicellular spheroids) human bone marrow stromal cell cultures.


Subject(s)
Biocompatible Materials/pharmacology , Calcium Compounds/pharmacology , Polyesters/pharmacology , Polyglactin 910/pharmacology , Silicates/pharmacology , 3T3 Cells , Adult , Aged , Animals , Biodegradation, Environmental , Bone Marrow Cells/cytology , Bone Marrow Cells/drug effects , Bone Marrow Cells/metabolism , Cell Adhesion/drug effects , Cell Movement/drug effects , Cell Proliferation/drug effects , Humans , Hydrogen-Ion Concentration/drug effects , Mesenchymal Stem Cells/cytology , Mesenchymal Stem Cells/drug effects , Mesenchymal Stem Cells/metabolism , Mice , Microscopy, Electron, Scanning , Middle Aged , Molecular Weight , Solvents , Spheroids, Cellular/cytology , Spheroids, Cellular/drug effects , Tensile Strength/drug effects , Time Factors
7.
Biomacromolecules ; 11(10): 2716-23, 2010 Oct 11.
Article in English | MEDLINE | ID: mdl-20843062

ABSTRACT

A novel process was developed to isolate poly([R]-3-hydroxyoctanoate-co-3-hydroxyhexanoate) (PHO) and poly([R]-3-hydroxy-ω-undecenoate-co-3-hydroxy-ω-nonenoate-co-3-hydroxy-ω-heptenoate) (PHUE) from Pseudomonas putida species. Methyl tert-butyl ether (MTBE), ethyl acetate, acetone, and methylene chloride efficiently extracted PHO from freeze-dried biomass. The ratio of solvent to biomass was 15:1 (vol/wt). The nonchlorinated solvents required 18 h of extraction to achieve methylene chloride's yield of 15 wt % within 60 min. In the case of PHUE, the yield was 15-17 wt % after 60 min of extraction at room temperature, independently of the solvent used. MTBE performed best in life cycle assessment (LCA) if contamination of the environment is avoided. Filtration of the extract containing 8 wt % of raw polyhydroxyalkanoate (PHA) through activated charcoal revealed colorless polymers with less than one endotoxin unit/g. The ratio (v/v) of the solution to activated charcoal was 2:1. The loss (impurities and polymers) amounted up to 50 wt %.


Subject(s)
Biocompatible Materials/isolation & purification , Polyhydroxyalkanoates/isolation & purification , Pseudomonas putida/chemistry , Solvents/chemistry , Biomass , Charcoal , Chromatography, Gel , Endotoxins/isolation & purification , Freeze Drying , Molecular Weight , Solutions
8.
Colloids Surf B Biointerfaces ; 76(1): 104-11, 2010 Mar 01.
Article in English | MEDLINE | ID: mdl-19914047

ABSTRACT

Polyhydroxyalkanoate (PHA) is a versatile class of biodegradable and biocompatible biopolyesters accumulated by many bacteria as intracellular carbon storage compound. The largest subclass consists of medium-chain-length (mcl) PHA which has a large potential in medical applications where flexible or elastomeric materials are required. Different extraction and purification methods for mcl-PHA are known to result in variations of polymer purities. In this study it was assessed whether this difference in quality may increase risk of failure of the implant material by enhanced colonization by Gram-negative and Gram-positive model pathogens (Staphylococcus aureus and Escherichia coli curli). Two types of mcl-PHA copolymers, poly(3-hydroxyoctanoate) (PHO) and the less known poly(3-hydroxyundecanoate) (PHUA), were evaluated for an impact of monomeric unit composition and degree of polymer purity on colonization by the model pathogens. It was found that film formation by bacteria on purified PHO and PHUA coatings was lower or similar to the one observed for polystyrene controls. The presence of proteins and lipopolysaccharide impurities originating from biotechnological production contributed to an increase in biofilm development probably by triggering the attachment of bacterial cells. In addition it was found that the model strains used differed significantly in colonizing the surfaces. For both types of mcl-PHAs E. coli curli was always a better biofilm former than S. aureus, which could be explained by the presence of curli (protein) fibers and a less hydrophilic cell wall.


Subject(s)
Bacterial Adhesion , Escherichia coli/chemistry , Polyhydroxyalkanoates/chemistry , Gels/chemistry , Kinetics
9.
J Biomed Mater Res A ; 93(4): 1391-403, 2010 Jun 15.
Article in English | MEDLINE | ID: mdl-19911384

ABSTRACT

There is a strong need for new biodegradable materials that are suitable for scaffolds in tissue engineering of tendons and ligaments. In many cases, quick degradation rates are favorable, however, with respect to ligament and tendon replacement, slowly degrading polymers are clearly favored. Prime candidates are members of the large class of polyhydroxyalkanoates (PHAs), which are thermoplastic/elastomeric biopolyesters that are slowly degraded by surface erosion. Moreover, their physico-mechanical properties can be tailored during biosynthesis in bacteria or by chemical modifications. They may be spun into fibers, coated on surfaces or be part of composites. This study has investigated the biocompatability of seven different thermoplastic or elastomeric PHAs using L929 murine fibroblast cells. Cell viability and proliferation over 7 days was analyzed with live/dead staining and a picogreen assay. In addition, extracellular matrix production was measured with the hydroxyproline assay after 14 days. It was found that cell attachment to the PHA film ranged from 85-99% after 7 days. Three PHA films (PHBV (92/8), PHOUE-POSS and PHUE-O3) supported similar cell viability in comparison to the controls performed on tissue culture plastic (polystyrene), whereas the biomaterials (PHUA, PHUE, PHB and PHOUE) showed fewer viable cells than in controls. PHB, PHUE-O3, and PHBV with a water contact angle below 85 degrees supported a similar amount of collagen production in comparison to the tissue culture plastic controls. PHUA, PHUE, PHOUE, and PHOUE-POSS showed a decrease in collagen production in comparison to the controls after 14 days. Overall, PHB, PHBV, and PHUE-O3 demonstrated good performance with regards to potential use as a tissue-engineering scaffold.


Subject(s)
Biocompatible Materials , Ligaments/pathology , Polyhydroxyalkanoates/chemistry , Tendons/pathology , Animals , Cell Survival , Collagen/chemistry , Fibroblasts/cytology , Fibroblasts/metabolism , Mice , Stress, Mechanical , Temperature , Time Factors , Tissue Engineering/methods , Tissue Scaffolds/chemistry
10.
Adv Drug Deliv Rev ; 53(1): 5-21, 2001 Dec 03.
Article in English | MEDLINE | ID: mdl-11733115

ABSTRACT

Polyhydroxyalkanoates (PHAs) comprise a large class of polyesters that are synthesized by many bacteria as an intracellular carbon and energy compound. Analysis of isolated PHAs reveal interesting properties such as biodegradability and biocompatibility. Research was focused only recently on the application of PHA in implants, scaffolds in tissue engineering, or as drug carriers. Such applications require that PHA be produced at a constant and reproducible quality. To date this can be achieved best through bacterial production in continuous culture where growth conditions are kept constant (chemostat). Recently, it was found that PHA producing bacteria are able to grow simultaneously limited by carbon and nitrogen substrates. Thus, it became possible to produce PHA at high yields on toxic substrate and also control its composition accurately (tailor-made synthesis). Finally, applications of PHA in medicine are discussed.


Subject(s)
Bacteria/chemistry , Bacterial Proteins , Polyesters/chemical synthesis , Polyesters/therapeutic use , Acyltransferases/biosynthesis , Acyltransferases/chemical synthesis , Acyltransferases/therapeutic use , Animals , Drug Carriers/chemical synthesis , Drug Carriers/metabolism , Drug Carriers/therapeutic use , Humans , Hydroxybutyrates/chemical synthesis , Hydroxybutyrates/metabolism , Hydroxybutyrates/therapeutic use , Polyesters/metabolism
11.
Biotechnol Bioeng ; 72(3): 278-88, 2001 Feb 05.
Article in English | MEDLINE | ID: mdl-11135197

ABSTRACT

Pseudomonas oleovorans (ATCC 29347) was grown in batch and chemostat cultures with citrate, hexanoate, heptanoate, octanoate, and nonanoate as single carbon substrates. The growth medium for batch cultures was adjusted such that nitrogen (NH(4)(+)) limitation terminated the exponential-growth phase. During batch cultivation with octanoate or nonanoate the biomass continued to increase after depletion of ammonium due to the accumulation of medium-chain-length poly[(R)-3-hydroxyalkanoates] (mcl-PHAs). Additionally, a significant rate of mcl-PHA accumulation was also observed in the exponential-growth phase of batch cultures. It is well known that the accumulation of reserve materials is strongly dependent on the ratio of nutrients (here of carbon, C, and of nitrogen, N) and that in a batch culture the ratio of C:N is continuously changing. Therefore, we have also investigated the effect of defined ratios of C:N under constant cultivation conditions, namely at a fixed dilution rate (D) in a chemostat fed with different medium C:N ratios. These experiments were performed at a constant D of 0.2 h(-1). The concentration of the nitrogen source in the inflowing medium (N()) was kept constant, while its carbon concentration (C()) was increased stepwise, resulting in an increase of the medium carbon to nitrogen ratio (C()/N() ratio). The culture parameters and the cell composition of steady-state cultures were determined as a function of the C()/N() ratio in the feed medium. Mcl-PHA accumulation was detected during growth with the fatty acids, and three distinct regimes of growth limitation were discovered: In addition to carbon limitation at low, and nitrogen limitation at high C()/N() ratios, an intermediate growth regime of simultaneous limitation by carbon and nitrogen was detected where both substrates were used to completion. The width of this dual-nutrient-limited growth regime was dependent on the change in the yield factors for carbon and nitrogen (Y(X/C), Y(X/N)) measured during single-nutrient-limited growth.


Subject(s)
Alkanes/metabolism , Carbon/metabolism , Carboxylic Acids/metabolism , Pseudomonas/growth & development , Pseudomonas/metabolism , Bioreactors , Culture Media/chemistry , Kinetics
13.
J Cardiovasc Pharmacol ; 30(2): 182-90, 1997 Aug.
Article in English | MEDLINE | ID: mdl-9269945

ABSTRACT

Diabetes mellitus leads to micro- and macroangiopathy with endothelial dysfunction. To investigate the direct influence of high glucose on endothelial cell structure and possible pharmacologic effects, seven different experimental protocols were carried out on endothelial cells in culture. There were four control groups with either 5 mM D-glucose alone, 5 mM D-glucose plus 15 mM L-glucose (for osmotic control), 5 mM D-glucose plus 500 nM celiprolol, or 5 mM D-glucose plus 57 nM nitrendipine. Three experimental groups had either 20 mM D-glucose alone, 20 mM D-glucose plus 500 nM celiprolol or 20 mM D-glucose plus 57 nM nitrendipine. Treatment of all groups started at the third passage of the cells and lasted until confluence was reached (5-8 days). The endothelial cells were fixed in paraformaldehyde and stained either with hematoxylin-eosin solution, with nitro blue tetrazolium for nicotinamide adenine dinucleotide phosphate (NADPH)- diaphorase staining, or actin staining with phalloidin was carried out. For quantitative analysis of the histologic specimens, the slides were viewed via a microscope and a videocamera. The pictures were converted digitally and could be analyzed with the videopicture-analyzing system, JAVA. In the four control groups, neither treatment with 15 mM L-glucose nor administration of celiprolol or nitrendipine had an effect on cell, cytoplasm, and nuclear area. The number of giant or polynuclear cells and the histochemical NADPH-diaphorase activity were not altered. Incubation of endothelial cells with 20 mM D-glucose for 5-8 days resulted in a significant increase in total and cytoplasmic area, as well as in the number of giant and polynuclear cells, whereas the nuclear area and the NADPH-diaphorase activity were significantly reduced. Concomitant treatment with celiprolol was able to reverse these alterations in endothelial structure significantly but had only a weak effect on the NADPH-diaphorase. Nitrendipine had no beneficial effect on the high D-glucose-induced cell alterations. The actin staining of the control cells showed the typical actin pattern with most of the actin filaments arranged at the periphery of the cells. Administration of 20 mM D-glucose resulted in a disturbance of the actin pattern, with most of the actin filaments now arranged in the middle of the cells. However, neither celiprolol nor nitrendipine exhibited a significant influence on this altered actin structure. High D-glucose treatment over several days thus leads to severe changes in endothelial cell structure, and celiprolol may have a beneficial effect on these hyperglycemia-induced cell alterations.


Subject(s)
Endothelium, Vascular/cytology , Glucose/pharmacology , Actins/metabolism , Adrenergic beta-Antagonists/pharmacology , Animals , Calcium Channel Blockers/pharmacology , Celiprolol/pharmacology , Cells, Cultured , Coloring Agents , Culture Media , Endothelium, Vascular/drug effects , NADPH Dehydrogenase/metabolism , Nitrendipine/pharmacology , Osmolar Concentration , Stereoisomerism , Swine
16.
Am J Public Health ; 82(4): 590-2, 1992 Apr.
Article in English | MEDLINE | ID: mdl-1546782

ABSTRACT

Human immunodeficiency virus (HIV) prevalence was studied in an unselected group of 216 female and transsexual prostitutes. Subjects were asked about age, biological sex, marital status, children, length of occupation, sexual practices, and drug abuse history. Blood was drawn on site. All 128 females who did not admit to drug abuse were seronegative; 2 of the 52 females (3.8%) who admitted to intravenous drug abuse were seropositive. In contrast, 11.1% of the 36 male transsexuals (including 3 out of 32 non-drug abusers) were seropositive. The results support the notion that vaginal transmission of HIV is less effective than anal transmission.


Subject(s)
HIV Seropositivity/epidemiology , HIV Seroprevalence , Sex Work/statistics & numerical data , Transsexualism , Adolescent , Adult , Contraceptive Devices, Male/statistics & numerical data , Employment/statistics & numerical data , Female , Humans , Israel/epidemiology , Male , Marriage/statistics & numerical data , Middle Aged , Parents , Risk Factors , Sexual Behavior , Substance Abuse, Intravenous/complications , Substance Abuse, Intravenous/epidemiology , Surveys and Questionnaires , Time Factors
17.
N Y State Dent J ; 58(3): 14-5, 1992 Mar.
Article in English | MEDLINE | ID: mdl-1565333
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