Patient factors associated with unidentified reactivity in solid-phase and polyethylene glycol antibody detection methods.

BACKGROUND: Several publications have reported an increase in nonspecific reactions when automated technologies such as solid phase are used for the detection of red blood cell alloantibodies. However, there is little known about patient-specific factors associated with these reactions and the clinical importance of these nonspecific reactions. STUDY DESIGN AND METHODS: We performed a 6-year retrospective review of our blood bank records and all newly reported unidentified (UID) reactivity using a test tube polyethylene glycol (t-PEG) and solid-phase method for the detection and identification of alloantibodies was recorded. Patient factors, such as underlying diagnosis, age, sex, ABO, Rh type, ethnicity, and subsequent antibody formation were recorded in each case. RESULTS: We determined that there was a significant increase in new UID reactions recorded in solid phase (20 per 10,000 tests) when compared to the t-PEG (1.8 per 10,000 tests) method for the detection of antibodies (p ≤ 0.0001). Solid-phase UID reactions were significantly associated with female sex (p = 0.04) and certain diagnoses, such as chronic or autoimmune disease, cancer, pregnancy, surgery, and trauma. Approximately 16% of patients developed a new auto- or alloantibody subsequent to their detected UID using solid phase. CONCLUSIONS: When solid phase is used for antibody identification, there is greater sensitivity toward nonspecific reactivity when compared to the t-PEG method. Patient sex and underlying diagnosis may explain the increased incidence of new UID reactivity in the solid-phase technology. Finally, UID reactivity should not be overlooked due to a notable percentage of subsequent clinically significant antibodies after UID detection.

Outcomes of Fecal Microbiota Transplantation for Clostridium difficile Infection in Patients with Inflammatory Bowel Disease.

BACKGROUND AND AIMS: Fecal microbiota transplantation (FMT) has recently been shown to be a promising therapy for recurrent and refractory Clostridium difficile infections (CDI) despite lack of protocol standardization. Patients with inflammatory bowel disease (IBD) present a particular challenge to CDI therapy as they are reported to have worse clinical outcomes, including higher colectomy rates and increased mortality. We aimed to assess the outcomes of FMT for recurrent CDI in patients with IBD at our healthcare system. METHODS: We constructed a retrospective cohort of all patients who underwent FMT at our healthcare system between December 2012 and May 2014. Patients with concurrent IBD were identified. We evaluated the differences in demographic and clinical characteristics, along with the outcomes to FMT between patients with IBD as compared to the general population. RESULTS: Over the study period, 201 patients underwent FMT of which 20 patients had concurrent IBD. Patients with IBD were younger but did not differ from the general population in terms of CDI risk factors or disease severity. The response to FMT and rate of CDI relapse in the IBD group were not statistically different compared to the rest of the cohort. The overall response rate in the IBD population was 75% at 12 weeks. Of the patients who failed FMT 4 of 5 patients had active or untreated IBD. CONCLUSION: Fecal microbiota transplantation provides a good alternative treatment option with high success rates for recurrent or refractory Clostridium difficile infection in patients with well-controlled IBD who fail standard antimicrobial therapy.

Inhibition of myeloperoxidase at the peak of experimental autoimmune encephalomyelitis restores blood-brain barrier integrity and ameliorates disease severity.

Oxidative stress is thought to contribute to disease pathogenesis in the central nervous system (CNS) disease multiple sclerosis (MS). Myeloperoxidase (MPO), a potent peroxidase that generates toxic radicals and oxidants, is increased in the CNS during MS. However, the exact mechanism whereby MPO drives MS pathology is not known. We addressed this question by inhibiting MPO in mice with experimental autoimmune encephalomyelitis (EAE) using our non-toxic MPO inhibitor N-acetyl lysyltyrosylcysteine amide (KYC). We found that therapeutic administration of KYC for 5 days starting at the peak of disease significantly attenuated EAE disease severity, reduced myeloid cell numbers and permeability of the blood-brain barrier. These data indicate that inhibition of MPO by KYC restores blood-brain barrier integrity thereby limiting migration of myeloid cells into the CNS that drive EAE pathogenesis. In addition, these observations indicate that KYC may be an effective therapeutic agent for the treatment of MS. We propose that during experimental autoimmune encephalomyelitis (EAE) onset macrophages and neutrophils migrate into the CNS and upon activation release myeloperoxidase (MPO) that promotes disruption of the blood-brain barrier (BBB) and disease progression. KYC restores BBB function by inhibiting MPO activity and in so doing ameliorates disease progression.

An increase in tolerogenic dendritic cell and natural regulatory T cell numbers during experimental autoimmune encephalomyelitis in Rras-/- mice results in attenuated disease.

R-Ras is a member of the Ras superfamily of small GTPases, which are regulators of various cellular processes, including adhesion, survival, proliferation, trafficking, and cytokine production. R-Ras is expressed by immune cells and has been shown to modulate dendritic cell (DC) function in vitro and has been associated with liver autoimmunity. We used Rras-deficient mice to study the mechanism whereby R-Ras contributes to autoimmunity using experimental autoimmune encephalomyelitis (EAE), a mouse model of the CNS autoimmune disease multiple sclerosis. We found that a lack of R-Ras in peripheral immune cells resulted in attenuated EAE disease. Further investigation revealed that, during EAE, absence of R-Ras promoted the formation of MHC II(low) DC concomitant with a significant increase in proliferation of natural regulatory T cells, resulting in an increase in their cell numbers in the periphery. Our study suggests a novel role for R-Ras in promoting autoimmunity through negative regulation of natural regulatory T cell numbers by inhibiting the development of MHCII(low) DC with tolerogenic potential.

Techniques of early respiratory management of very low and extremely low birth weight infants.

The generalized anatomic and physiologic immaturity of preterm infants of very low birth weight (VLBW) (

Predictors of fecal transplant failure.

BACKGROUND: Clostridium difficile infection (CDI) is a significant healthcare burden, with increased morbidity and mortality. Traditional treatment regimens using antibiotics for recurrent CDI are significantly less successful compared with 80-90% with fecal microbiota transplantation (FMT). There is a paucity of data on failure rates and mortality after FMT in CDI. This study aims to identify the rates of failure, relapse, and mortality associated with FMT as well as the risk factors for FMT failure. METHODS: A large retrospective cohort study was carried out including all patients who underwent FMT from December 2012 through May 2014. Patient factors (demographics, comorbidities, immune-suppression, transplant history, antibiotics used, hospitalization, and surgeries), disease factors (number of episodes of CDI, treatments, and severity), and transplant factors (route and number of FMT) were examined. Failure of treatment was defined as no resolution of diarrhea in patients who had been treated with one or more fecal microbiota transplantation within 90 days of FMT. RESULTS: A total of 201 patients (age 66.6±18.3 years, 62.2% women) were included. The overall failure rate was 12.4%. Patients with failed fecal transplant had increased number of FMTs compared with those who responded (mean 1.92±0.997 vs. 1.29±0.615; P=0.004). No colectomies or death related to CDI were found in our patient population. Significant predictors of failure were female sex (P=0.016), previous hospitalization (P=0.006), and surgery before FMT (P=0.005). The overall mortality rate was 9.0% and failure of FMT was associated with an increased risk of death (odds ratio=5.833, confidence interval 2.01-16.925; P<0.05). CONCLUSION: FMT is a suitable alterative to antibiotic use for recurrent CDIs, with a high success rate. The results indicate that hospital-acquired CDI may be a predictor of failure of FMT.

Anti-inflammatory mechanisms of IFN-γ studied in experimental autoimmune encephalomyelitis reveal neutrophils as a potential target in multiple sclerosis.

Multiple sclerosis (MS) is an autoimmune disease of the central nervous system (CNS) mediated by T helper (h)1 and/or Th17 CD4 T cells that drive inflammatory lesion development along with demyelination and neuronal damage. Defects in immune regulatory mechanisms are thought to play a role in the pathogenesis of MS. While an early clinical trial indicated that IFN-γ administration was detrimental to MS, studies in the mouse model of MS, experimental autoimmune encephalomyelitis (EAE), indicated that IFN-γ exhibits a number of anti-inflammatory properties within the CNS. These mechanisms include inhibition of IL-17 production, induction of regulatory T cells, T cell apoptosis and regulation of chemokine production. Mice deficient in IFN-γ or its receptor were instrumental in deciphering the anti-inflammatory properties of IFN-γ in the CNS. In particular, they revealed that IFN-γ is a major regulator of neutrophil recruitment into the CNS, which by a variety of mechanisms including disruption of the blood-brain-barrier (BBB) and production of reactive oxygen species are thought to contribute to the onset and progression of EAE. Neutrophils were also shown to be instrumental in EAE relapses. To date neutrophils have not been appreciated as a driver of MS, but more recently based largely on strong EAE data this view is being reevaluated by some investigators in the field.

2B4 Is Dispensable for T-Dependent B Cell Immune Responses, but Its Deficiency Leads to Enhanced T-Independent Responses Due to an Increase in Peritoneal Cavity B1b Cells.

The signaling lymphocyte activation molecule (SLAM) family plays important roles in adaptive immune responses. Herein, we evaluated whether the SLAM family member 2B4 (CD244) plays a role in immune cell development, homeostasis and antibody responses. We found that the splenic cellularity in Cd244-/- mice was significantly reduced due to a reduction in both CD4 T cells and follicular (Fo) B cells; whereas, the number of peritoneal cavity B cells was increased. These findings led us to examine whether 2B4 modulates B cell immune responses. When we examined T-dependent B cell responses, while there was no difference in the kinetics or magnitude of the antigen-specific IgM and IgG1 antibody response there was a reduction in bone marrow (BM) memory, but not plasma cells in Cd244-/- mice. When we evaluated T-independent immune responses, we found that antigen-specific IgM and IgG3 were elevated in the serum following immunization. These data indicate that 2B4 dampens T-independent B cell responses due to a reduction in peritoneal cavity B cells, but has minimal impact on T-dependent B cell responses.

Lymphocytes with cytotoxic activity induce rapid microtubule axonal destabilization independently and before signs of neuronal death.

MS (multiple sclerosis) is the most prevalent autoimmune disease of the CNS (central nervous system) historically characterized as an inflammatory and demyelinating disease. More recently, extensive neuronal pathology has lead to its classification as a neurodegenerative disease as well. While the immune system initiates the autoimmune response it remains unclear how it orchestrates neuronal damage. In our previous studies, using in vitro cultured embryonic neurons, we demonstrated that MBP (myelin basic protein)-specific encephalitogenic CD4 T-cells induce early neuronal damage. In an extension of those studies, here we show that polarized CD4 Th1 and Th17 cells as wells as CD8 T-cells and NK (natural killer) cells induce microtubule destabilization within neurites in a contact-independent manner. Owing to the cytotoxic potential of these immune cells, we isolated the luminal components of lytic granules and determined that they were sufficient to drive microtubule destabilization. Since lytic granules contain cytolytic proteins, we determined that the induction of microtubule destabilization occurred prior to signs of apoptosis. Furthermore, we determined that microtubule destabilization was largely restricted to axons, sparing dendrites. This study demonstrated that lymphocytes with cytolytic activity have the capacity to directly drive MAD (microtubule axonal destabilization) in a bystander manner that is independent of neuronal death.

The use of computer technology to reduce and prevent college drinking.

Underage drinking, or binge drinking, has become a major concern in U.S. society. At The University of Tennessee (UT) a computer-based intervention was put into place for the past 3 years with funding from the Substance Abuse and Mental Health Services Administration (SAMHSA). The intervention was provided to all college students via UT's computer network system and was completed mostly online. Students were given a computerized, standardized assessment of alcohol use, and then a brief intervention was given based on the students' information. The intervention targeted students who were at highest risk for developing unsafe alcohol behaviors and/or increasing prior alcohol consumption habits in their first year of college. More than 54,000 graduate and undergraduate students completed the program. Since the launch of the program binge drinking has dropped 27% on campus, frequent binge drinking dropped 44%, and the number of liquor law violations to 18- to 20-year-olds decreased from 542 in 2004 to approximately 158 in 2007. The use of a computer-based intervention was comprehensive, low cost, and required low maintenance.

Use of X-ray diffraction, molecular simulations, and spectroscopy to determine the molecular packing in a polymer-fullerene bimolecular crystal.

The molecular packing in a polymer: fullerene bimolecular crystal is determined using X-ray diffraction (XRD), molecular mechanics (MM) and molecular dynamics (MD) simulations, 2D solid-state NMR spectroscopy, and IR absorption spectroscopy. The conformation of the electron-donating polymer is significantly disrupted by the incorporation of the electron-accepting fullerene molecules, which introduce twists and bends along the polymer backbone and 1D electron-conducting fullerene channels.