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1.
Transpl Immunol ; 75: 101726, 2022 12.
Article in English | MEDLINE | ID: mdl-36183942

ABSTRACT

Bone marrow-derived long-lived plasma cells (LLPCs) are thought to be a major source of alloantibody in sensitized transplant patients. However, studies of LLPCs have been hampered not only by the fact that they are rare and difficult to isolate and culture but also due to the lack of consensus regarding a definitive cell-surface phenotype. The goal of the current study was to determine if LLPCs have a specific, stable cell-surface phenotype. PCs were isolated from high-volume (120cc) bone marrow aspirates that were enriched first by negative selection then positive selection using anti-CD38 antibody-coated beads and purified by cell sorting. A typical isolation resulted in >100,000 PCs that were sorted into 4 populations with variable numbers of PCs: CD19+/CD138+/CD38Hi (64.1% of the PCs), CD19-/CD138+/CD38Hi (20.9%), CD19+/CD138-/CD38Hi (10.7%), and CD19-/CD138-/CD38Hi (4.3%). The purity of each subset was 96-99%. Each subset contained PCs secreting IgG and IgA. Measles- and tetanus-specific PCs (i.e. putative IgG secreting, antigen-specific LLPCs). LLPCs were identified in both the CD19+/CD138+/CD38Hi and CD19-/CD138+/CD38Hi subsets and in the smaller CD138- subsets (when pooled). Thus, all CD38Hi subsets contained LLPCs. Cultured PCs maintained viability (>50%) and function and could be retrieved for analyses. During 7 days of culture, cell surface expression changed from baseline in many PCs. For example, approximately 20% of CD19 + CD138+/CD38Hi cells (the largest PC subset) became CD19-. CFSE assays showed no division and only a small percentage of LLPCs were Ki-67 positive suggesting that the cells did not divide in culture and that the antibody detected was not from plasmablasts. We conclude that human bone marrow LLPCs have a heterogeneous expression of CD19 and CD138, which can change during cell culture. The fact that LLPCs were found in all four subsets raises the possibility that a large percentage of PCs in the bone marrow may be LLPCs.


Subject(s)
Bone Marrow , Plasma Cells , Humans , Antigens, CD19/metabolism , Immunoglobulin G/metabolism , Phenotype
2.
Am J Physiol Endocrinol Metab ; 321(1): E105-E121, 2021 07 01.
Article in English | MEDLINE | ID: mdl-33998291

ABSTRACT

Obesity is accompanied by numerous systemic and tissue-specific derangements, including systemic inflammation, insulin resistance, and mitochondrial abnormalities in skeletal muscle. Despite growing recognition that adipose tissue dysfunction plays a role in obesity-related disorders, the relationship between adipose tissue inflammation and other pathological features of obesity is not well-understood. We assessed macrophage populations and measured the expression of inflammatory cytokines in abdominal adipose tissue biopsies in 39 nondiabetic adults across a range of body mass indexes (BMI 20.5-45.8 kg/m2). Skeletal muscle biopsies were used to evaluate mitochondrial respiratory capacity, ATP production capacity, coupling, and reactive oxygen species production. Insulin sensitivity (SI) and ß cell responsivity were determined from test meal postprandial glucose, insulin, c-peptide, and triglyceride kinetics. We examined the relationships between adipose tissue inflammatory markers, systemic inflammatory markers, SI, and skeletal muscle mitochondrial physiology. BMI was associated with increased adipose tissue and systemic inflammation, reduced SI, and reduced skeletal muscle mitochondrial oxidative capacity. Adipose-resident macrophage numbers were positively associated with circulating inflammatory markers, including tumor necrosis factor-α (TNFα) and C-reactive protein (CRP). Local adipose tissue inflammation and circulating concentrations of TNFα and CRP were negatively associated with SI, and circulating concentrations of TNFα and CRP were also negatively associated with skeletal muscle oxidative capacity. These results demonstrate that obese humans exhibit increased adipose tissue inflammation concurrently with increased systemic inflammation, reduced insulin sensitivity, and reduced muscle oxidative capacity and suggest that adipose tissue and systemic inflammation may drive obesity-associated metabolic derangements.NEW AND NOTEWORTHY Adipose inflammation is proposed to be at the nexus of the systemic inflammation and metabolic derangements associated with obesity. The present study provides evidence to support adipose inflammation as a central feature of the pathophysiology of obesity. Adipose inflammation is associated with systemic and peripheral metabolic derangements, including increased systemic inflammation, reduced insulin sensitivity, and reduced skeletal muscle mitochondrial respiration.


Subject(s)
Abdominal Fat/pathology , Inflammation/pathology , Insulin Resistance , Macrophages/pathology , Obesity/pathology , Abdominal Fat/chemistry , Abdominal Fat/metabolism , Adult , Biomarkers/analysis , Body Mass Index , C-Reactive Protein/analysis , Cell Count , Cytokines/analysis , Female , Gene Expression , Humans , Inflammation/genetics , Male , Middle Aged , Mitochondria, Muscle/metabolism , Obesity/physiopathology , Oxygen Consumption , Tumor Necrosis Factor-alpha/blood
3.
Front Immunol ; 9: 607, 2018.
Article in English | MEDLINE | ID: mdl-29651289

ABSTRACT

Endotoxemia is a condition in which endotoxins enter the blood stream and cause systemic and sometimes lethal inflammation. Zebra fish provides a genetically tractable model organism for studying innate immunity, with additional advantages in live imaging and drug discovery. However, a bona fide endotoxemia model has not been established in zebra fish. Here, we have developed an acute endotoxemia model in zebra fish by injecting a single dose of LPS directly into the circulation. Hallmarks of human acute endotoxemia, including systemic inflammation, extensive tissue damage, circulation blockade, immune cell mobilization, and emergency hematopoiesis, were recapitulated in this model. Knocking out the adaptor protein Myd88 inhibited systemic inflammation and improved zebra fish survival. In addition, similar alternations of pathways with human acute endotoxemia were detected using global proteomic profiling and MetaCore™ pathway enrichment analysis. Furthermore, treating zebra fish with a protein tyrosine phosphatase nonreceptor type 11 (Shp2) inhibitor decreased systemic inflammation, immune mobilization, tissue damage, and improved survival in the endotoxemia model. Together, we have established and characterized the phenotypic and gene expression changes of a zebra fish endotoxemia model, which is amenable to genetic and pharmacological discoveries that can ultimately lead to a better mechanistic understanding of the dynamics and interplay of the innate immune system.


Subject(s)
Disease Models, Animal , Endotoxemia/immunology , Immunity, Innate , Inflammation/immunology , Zebrafish/immunology , Animals , Blood Circulation , Cell Movement , Cells, Cultured , Fish Proteins/antagonists & inhibitors , Gene Expression Profiling , Hematopoiesis , Humans , Immunity, Cellular , Lipopolysaccharides/administration & dosage , Myeloid Differentiation Factor 88/antagonists & inhibitors , Protein Tyrosine Phosphatase, Non-Receptor Type 11/antagonists & inhibitors , Signal Transduction
4.
Transplantation ; 101(6): 1222-1227, 2017 06.
Article in English | MEDLINE | ID: mdl-27379560

ABSTRACT

BACKGROUND: We previously showed that bortezomib (BTZ) partially depletes plasma cells, yet has limited efficacy for desensitization in kidney transplant candidates when up to 16 doses is given. METHODS: This study aimed to determine the safety and efficacy of 32 doses of BTZ (1.3 mg/m of body surface area) in 10 highly sensitized kidney transplant candidates with alloantibodies against their intended living donor. RESULTS: Dose reduction was needed in 2 patients and 2 others completely discontinued therapy for adverse events. Anti-HLA antibodies mean fluorescence intensity (MFI) values were stable prior to BTZ (P = 0.96) but decreased after therapy (mean decrease of 1916 [SE, 425] MFI, P < 0.01). No patient developed a negative crossmatch against their original intended donor, and the calculated panel-reactive antibodies based on MFI of 2000, 4000, and 8000 was unchanged in all patients. CONCLUSIONS: These data suggest that 32 doses of BTZ monotherapy was not well tolerated and resulted in only a modest reduction in anti-HLA antibodies.


Subject(s)
Bortezomib/administration & dosage , Desensitization, Immunologic/methods , Graft Rejection/prevention & control , Graft Survival/drug effects , HLA Antigens/immunology , Histocompatibility , Immunosuppressive Agents/administration & dosage , Isoantibodies/blood , Kidney Transplantation/methods , Adult , Biomarkers/blood , Bortezomib/adverse effects , Down-Regulation , Drug Administration Schedule , Female , Graft Rejection/immunology , Histocompatibility Testing , Humans , Immunosuppressive Agents/adverse effects , Kidney Transplantation/adverse effects , Living Donors , Male , Middle Aged , Minnesota , Prospective Studies , Time Factors , Treatment Outcome
5.
Indoor Built Environ ; 24(7): 970-985, 2015 Nov.
Article in English | MEDLINE | ID: mdl-26539060

ABSTRACT

Social housing organisations are increasingly installing renewable energy technologies, particularly for the provision of heating and hot water. To meet carbon reduction targets, uptake and installation must allow occupants to use the technology effectively. This paper describes research which investigated the service of installing heat pumps into UK social housing properties, from both landlords' and tenants' experiences. Adopting a user centred design approach, the research was in three phases: an exploration study to investigate landlords' and tenants' experiences of heat pump installation and use; refinement and development of the requirements for improved service delivery, primarily technology introduction and control; and the development and initial evaluation of an information leaflet as a key touchpoint in the service delivery. Recommendations for improved service delivery, to enable heat pumps to be accepted and used more effectively, are presented, as well as reflection on the process of applying user centred design in this context. In a relatively immature area of industry, installations to date have been heavily focused on technical aspects. This paper provides an insight into the human aspects of the service delivery of heat pumps in social housing, providing designers and social housing landlords with insight about how to improve the service.

6.
Transplantation ; 97(3): 247-57, 2014 Feb 15.
Article in English | MEDLINE | ID: mdl-24056631

ABSTRACT

Alloantibody can be a major barrier to successful organ transplantation; however, therapy to control antibody production or to alter its impact on the allograft remains limited. The goal of this review is to examine the regulatory steps that are involved in the generation of alloreactive B cells, with a specific emphasis on how known mechanisms relate to clinical situations in transplant recipients. Thus, we will examine the process of activation of mature, naïve B cells and how this relates to de novo antibody production. The role of long-lived plasma cells in persistent antibody production and the factors regulating their longevity will be explored. The regulation of memory B cells and their possible roles in alloimmunity also will be assessed. Finally, we will review current therapeutic approaches aimed at controlling alloantibody and assess their efficacy. By examining the pathways to antibody production mechanistically, we hope to identify important gaps in our current knowledge and gain insight into possible new therapeutic approaches to overcoming antibody in transplant patients.


Subject(s)
B-Lymphocytes/immunology , Down-Regulation , Immunity, Humoral/physiology , Organ Transplantation/methods , Animals , Antibodies/chemistry , Apoptosis , B-Lymphocytes/cytology , Bone Marrow Cells/cytology , Disease Models, Animal , Graft Rejection , Humans , Immune Tolerance , Immunologic Memory , Isoantibodies/chemistry , Kidney Transplantation/methods , Liver Transplantation , Lymphoid Tissue/pathology , Mice , Plasma Cells/cytology
7.
J Phys Condens Matter ; 25(35): 355001, 2013 Sep 04.
Article in English | MEDLINE | ID: mdl-23860398

ABSTRACT

The way in which point defects interact with grain boundaries in oxides is important for understanding radiation damage evolution, sintering, and many other technologically important applications. Here, we examine how vacancies interact with three different grain boundaries in MgO, chosen as a model oxide ceramic. Further, we compare the vacancy interaction with both pristine (as constructed) and 'damaged' boundaries, in which excess interstitials are placed in the boundary plane to mimic the structure after a damage event. We find that the excess interstitials significantly change the interaction of the vacancies with the boundaries and that this change is sensitive to the atomic structure of the boundary. We further observe that complex electrostatic effects arise that can dominate the interaction. These results show that, as boundaries absorb defects, their interaction with other defects will change dramatically.


Subject(s)
Magnesium Oxide/chemistry , Models, Chemical , Models, Molecular , Absorption , Computer Simulation , Molecular Conformation , Surface Properties
8.
J Clin Microbiol ; 48(10): 3582-92, 2010 Oct.
Article in English | MEDLINE | ID: mdl-20668125

ABSTRACT

It is not well understood why strains of community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA), a major cause of skin and soft tissue infections, became successful so quickly, overtaking the place of methicillin-sensitive S. aureus (MSSA) in many communities. To evaluate the genetic basis of differences in their virulence traits, 293 S. aureus isolates consisting of three cohorts, genotypically defined clinical CA-MRSA (n = 77), clinical MSSA (n = 103), and nasal carriage MSSA (n = 113), collected over a 19-year period in two Midwestern states in the United States, were (i) extensively genotyped and (ii) screened for 40 known virulence genes which included those for enterotoxins, leukocidins, hemolysins, and surface proteins and several newly identified putative toxin genes from the USA400 lineage of CA-MRSA. Genotypically, nasal carriage and clinical MSSA isolates were much more diverse than was the CA-MRSA group, which was found to be of USA400 lineage only. Virulence gene profiles of the three groups showed that CA-MRSA strains harbored significantly higher percentages (≥95%; P value, <0.05) of the sea, sec, sec4, seg2, seh, sek, sel, sel2, ear, ssl1, lpl10, lukSF-PV, lukD, lukE, and clfA genes than did the carriage and the clinical MSSA group (range, 0% to 58%). Genes of the enterotoxin gene cluster, seg, sei, sem, sen, and seo, were present in the clinical and carriage isolates but not in the CA-MRSA group. These results suggest that the presence of additional virulence factors in USA400 CA-MRSA strains compared to the nasal carriage and clinical MSSA strains probably contributed to their enhanced virulence.


Subject(s)
Carrier State/microbiology , Community-Acquired Infections/microbiology , Staphylococcal Infections/microbiology , Staphylococcus aureus/genetics , Virulence Factors/genetics , DNA, Bacterial/genetics , Genotype , Humans , Methicillin Resistance , Nasal Mucosa/microbiology , Polymerase Chain Reaction , Staphylococcus aureus/isolation & purification , United States
9.
J Natl Med Assoc ; 97(4): 527-34, 2005 Apr.
Article in English | MEDLINE | ID: mdl-15868772

ABSTRACT

The environmental scan is a tool that can be utilized to collect data to design health programs uniquely tailored to the needs of communities. However, it remains relatively undefined, unevaluated and underutilized in the field of public health. While individual studies indicate the utility of the environmental scan for public health, it is difficult to find a theoretical framework or guidelines on how to design, implement or evaluate the process within public health practice. The purpose of this study was to elicit lessons learned to maximize the utility of the environmental scan as a tool for public health. This process occurred through the development and implementation of an environmental scan as part of the needs-assessment phase of a project to increase cancer screening among African Americans in Baltimore, MD. Data collection methods for the environmental scan included a review of community stakeholders, cancer incidence and community assets and liabilities in target communities, focus-group sessions and key informant interviews with service providers. The environmental scan was conducted in 2003 and allowed for rapid acquisition and use of information about events, trends and relationships in the neighborhoods targeted for our project and enabled researchers to move forward with implementing the cancer-screening project. The researchers conclude that the environmental scan has considerable potential to be a creative, responsive, cost-effective and mobilizing tool for public health practice. However, further application and critical review are necessary to make it a more effective public health tool and an established research methodology.


Subject(s)
Environmental Exposure/prevention & control , Environmental Monitoring/methods , Mass Screening/organization & administration , Neoplasms/prevention & control , Public Health Practice/standards , Environmental Health , Female , Humans , Male , Sensitivity and Specificity , United States , Urban Health
10.
J Am Diet Assoc ; 104(7): 1080-5, 2004 Jul.
Article in English | MEDLINE | ID: mdl-15215765

ABSTRACT

OBJECTIVE: The objective of this study was to determine whether there is an association between body image perception and weight status as measured by the body mass index among a group of fourth graders in Maryland. DESIGN: Cross-sectional data on height, weight, and body image were collected in the classroom. At risk for being overweight and being overweight designations were assigned to participants with body mass index (BMI) percentile values for age and sex of >/=85 to <95 and BMI >/=95, respectively. Students selected a figure (range 1 to 7) to represent their current and ideal images. SUBJECTS: The subjects of this study were 524 fourth-grade public school students (54% girls; 61% white; mean age, 9.2 years) from three geographically distinct regions in Maryland (38.6% urban, 30.7% suburban, 30.7% rural). Statistical analyses chi(2) tests were used to compare weight status with sex, race, geographic location, and body image discrepancy categories. One-way analysis of variance was used to compare BMI and body image scores with sex and race/ethnicity to geographic location. RESULTS: Thirteen percent of students were overweight, and 15% were at risk of overweight. There was no association between weight status and race, body image perception, or geographic location. African Americans chose larger figures than whites and other races to represent their current and ideal images and were most satisfied with their body size. CONCLUSIONS: Perceptions of body image are formed early in life. Dietitians can provide guidance on appropriate weight and body size to children, parents, and school professionals. Dietitians can also use their influence to secure funding for nutrition education programs.


Subject(s)
Body Image , Body Weight , Obesity/psychology , Self Concept , Students/statistics & numerical data , Black or African American , Analysis of Variance , Body Mass Index , Body Weight/ethnology , Child , Child Nutritional Physiological Phenomena , Cross-Sectional Studies , Ethnicity , Female , Humans , Male , Maryland/epidemiology , Obesity/epidemiology , Obesity/ethnology , Rural Health , Schools/statistics & numerical data , Suburban Health , Urban Health , White People
11.
J Am Diet Assoc ; 104(3): 420-3, 2004 Mar.
Article in English | MEDLINE | ID: mdl-14993865

ABSTRACT

The objective of this study was to describe breakfast and lunch consumption patterns of fourth-grade students from selected public schools in Maryland and how they differ by geographic location. Data were collected from a sample of 540 fourth-grade public school children (46% male, 62% white; mean age=9 years) from three geographically distinct regions of Maryland (30% rural, 30% suburban, and 40% urban). Data on breakfast and lunch consumption were collected using an in-classroom questionnaire. chi(2) tests were used to compare skipping meal behavior by geographic location. Twenty percent of fourth-grade students reported skipping breakfast and/or lunch at least three times per week. Urban students were more than twice as likely to skip breakfast and to eat school-prepared meals compared with suburban and rural students. Dietitians in all regions need to explore new ways to encourage regular meal consumption among students in their schools.


Subject(s)
Child Nutritional Physiological Phenomena , Feeding Behavior , Food Services , Students/statistics & numerical data , Child , Child Welfare , Demography , Female , Humans , Male , Maryland/epidemiology , Rural Health , Schools/statistics & numerical data , Suburban Health , Surveys and Questionnaires , Urban Health
12.
Ann Surg ; 238(3): 349-55; discussion 355-7, 2003 Sep.
Article in English | MEDLINE | ID: mdl-14501501

ABSTRACT

INTRODUCTION: Shock resuscitation leads to visceral edema often precluding abdominal wall closure. We have developed a staged approach encompassing acute management through definitive abdominal wall reconstruction. The purpose of this report is to analyze our experience with this technique applied to the treatment of patients with open abdomen and giant abdominal wall defects. METHODS: Our management scheme for giant abdominal wall defects consists of 3 stages: stage I, absorbable mesh insertion for temporary closure (if edema quickly resolves within 3-5 days, the mesh is gradually pleated, allowing delayed fascial closure); stage II, absorbable mesh removal in patients without edema resolution (2-3 weeks after insertion to allow for granulation and fixation of viscera) and formation of the planned ventral hernia with either split thickness skin graft or full thickness skin closure over the viscera; and stage III, definitive reconstruction after 6-12 months (allowing for inflammation and dense adhesion resolution) by using the modified components separation technique. Consecutive patients from 1993 to 2001 at a single institution were evaluated. Outcomes were analyzed by management stage, with emphasis on wound related morbidity and mortality, and fistula and recurrent hernia rates. RESULTS: Two hundred seventy four patients (35 with sepsis, 239 with hemorrhagic shock) were managed. There were 212 males (77%), and mean age was 37 (range, 12-88). The average size of the defects was 20 x 30 cm. In the stage I group, 108 died (92% of all deaths) because of shock. The remaining 166 had temporary closure with polyglactin 910 woven absorbable mesh. As visceral edema resolved, bedside pleating of the absorbable mesh allowed delayed fascial closure in 37 patients (22%). In the stage II group, 9 died (8% of all deaths) from multiple organ failure associated with their underlying disease process, and 96% of the remaining 120 had split-thickness skin graft placed over the viscera. No wound related mortality occurred. There were a total of 14 fistulae (5% of total, 8% of survivors). In the stage III group, to date, 73 of the 120 have had definitive abdominal wall reconstruction using the modified components separation technique. There were no deaths. Mean follow-up was 24 months, (range 2-60). Recurrent hernias developed in 4 of these patients (5%). CONCLUSIONS: The staged management of patients with giant abdominal wall defects without the use of permanent mesh results in a safe and consistent approach for both initial and definitive management with low morbidity and no technique-related mortality. Absorbable mesh provides effective temporary abdominal wall defect coverage with a low fistula rate. Because of the low recurrent hernia rate and avoidance of permanent mesh, the components separation technique is the procedure of choice for definitive abdominal wall reconstruction.


Subject(s)
Abdominal Injuries/etiology , Abdominal Wall/surgery , Absorbable Implants , Compartment Syndromes/surgery , Fluid Therapy/adverse effects , Hernia, Ventral/surgery , Intestinal Fistula/surgery , Resuscitation/adverse effects , Surgical Mesh , Abdominal Injuries/surgery , Adult , Compartment Syndromes/etiology , Female , Hernia, Ventral/etiology , Humans , Intestinal Fistula/etiology , Laparotomy , Male , Polyglactin 910 , Resuscitation/methods , Shock, Hemorrhagic/therapy , Shock, Septic/therapy , Skin Transplantation , Time Factors
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