Loss of cooperative function of transforming growth factor-beta signaling proteins, smad3 with embryonic liver fodrin, a beta-spectrin, in primary biliary cirrhosis.

Modulation of fibrogenesis, epithelial, and mesenchymal cell fates are prominent effects of transforming growth factor-beta (TGF-beta) signaling by Smad proteins. We have previously shown that Smad2 and Smad3 insufficiency leads to a loss of bile ducts. In addition, Smad3/4 activity is mediated by embryonic liver fodrin (ELF), a beta-Spectrin. In mouse elf(-/-) mutants and in liver explant cultures, loss of ELF function results in T lymphocytic proliferation and absent intrahepatic bile ducts. A similar phenotype is seen in a number of cholestatic diseases with progressive loss of intrahepatic bile ducts and fibrosis. However, the expression patterns of Smads or role of ELF in cholestatic and fibrotic liver diseases are not yet known. METHODS/RESULTS: We investigated the role of ELF in primary biliary cirrhosis (PBC), autoimmune hepatitis C, chronic viral hepatitis and in livers from mice deficient in Smad2/Smad3. We generated elf(+/-) mutant mice and analyzed for chronic liver disease and hepatocellular cancer (HCC) from 6 to 12 months. Perturbations in ELF expression were consistently seen only in PBC tissues. ELF expression was similarly aberrant in tissues from Smad2(+/-)/Smad3(+/-) mutant mice. Further studies indicated that ELF mislocalization is correlated with aberrant localization of Smad3 in some PBC tissues. Thirteen of 17 elf(+/-) mutant mice developed steatosis, fibrosis, hepatic dysplasia, with HCC in two mice. CONCLUSIONS: These results suggest that a compromised cytoarchitecture and polarized trafficking of TGF-beta signaling molecules, ELF and Smad3 are involved in the pathogenesis of PBC as well as HCC.     

Alloreactive CD4+ T lymphocytes can exert cytotoxicity to chronic myeloid leukaemia cells processing and presenting exogenous antigen

Existing evidence supports that CD4⁺ T lymphocytes play a role in the graft-versus-leukaemia (GVL) reaction after allogeneic bone marrow transplantation (BMT) for chronic myeloid leukaemia (CML), not only as initiators of the immune response but also as effectors of GVL. In BMT between HLA-identical pairs this CD4-mediated GVL would require CML cells to process and present antigens through MHC class II molecules. To investigate whether CML cells are capable of processing and presenting antigens, and suitable targets for CD4⁺ T-cell-mediated cytotoxicity, we generated HLA-DR1-restricted CD4⁺ cytotoxic T-cell clones that specifically recognized tuberculous purified protein derivative (PPD). We have shown that CML cells and B lymphoblastoid cell line (B-LCL) cells but not PHA-blasts from patients with CML processed exogenous antigen, PPD, and induced proliferative and cytotoxic CD4⁺ T-cell responses. Antigen presentation was blocked by antibodies to HLA-DR but not to MHC class I and by treatment with chloroquine and brefeldin. This indicates that CML cells use a classic MHC class II antigen processing pathway to present PPD antigens to CD4⁺ T cells. Cytotoxicity to CML was shown by antibody blocking studies to be mediated mainly through fas antigen. These findings indicate that donor CD4⁺ T cells alone are sufficient to mediate GVL effects following allogeneic BMT for CML.     

The FOUR Score Predicts Mortality,Endotracheal Intubation and ICU Length of Stay After Traumatic Brain Injury

Background

The Glasgow Coma Scale (GCS) is the most widely accepted scale for assessing levels of consciousness, clinical status, as well as prognosis of traumatic brain injury (TBI) patients. The Full Outline of UnResponsiveness (FOUR) score is a new coma scale developed addressing the limitations of the GCS. The aim of this prospective cohort study was to compare the performance of the FOUR score vs. the GCS in predicting TBI outcomes.

Methods

From April to July 2011, 60 consecutive adult patients with TBI admitted to the Alexandria Main University Hospital intensive care units (ICU) were enrolled in the study. GCS and FOUR score were documented on arrival to emergency room. Outcomes were in-hospital mortality, unfavorable outcome [Glasgow outcome scale extended (GOSE) 1–4], endotracheal intubation, and ICU length of stay (LOS).

Results

Fifteen (25 %) patients died and 35 (58 %) had unfavorable outcome. When predicting mortality, the FOUR score showed significantly higher area under receiver operating characteristic curve (AUC) than the GCS score (0.850 vs. 0.796, p = 0.025). The FOUR score and the GCS score were not different in predicting unfavorable outcome (AUC 0.813 vs. 0.779, p = 0.136) and endotracheal intubation (AUC 0.961 vs. 0.982, p = 0.06). Both scores were good predictors of ICU LOS (r ² = 0.40 [FOUR score] vs. 0.41 [GCS score]).

Conclusions

The FOUR score was superior to the GCS in predicting in-hospital mortality in TBI patients. There was no difference between both scores in predicting unfavorable outcome, endotracheal intubation, and ICU LOS.     

Association of TM4SF4 with the Human Thiamine Transporter-2 in Intestinal Epithelial Cells

Background

The human thiamine transporter-2 (hTHTR-2) is involved in the intestinal absorption of thiamine. Recent studies with membrane transporters of other nutrients/substrates have shown that they have associated proteins that affect different aspects of their physiology and cell biology. Nothing is known about protein(s) that interact with hTHTR-2 in intestinal epithelial cells and influence its physiological function and/or its cell biology.

Aims

The aim of this study was to identify protein partner(s) that interact with hTHTR-2 in human intestinal cells and determine the physiological/biological consequence of that interaction.

Methods

The yeast split-ubiquitin two-hybrid approach was used to screen a human intestinal cDNA library. GST-pull-down and cellular co-localization approaches were used to confirm the interaction between hTHTR-2 and the associated protein(s). The effect of such an interaction on hTHTR-2 function was examined by ³H-thiamine uptake assays.

Results

Our screening results identified the human TransMembrane 4 SuperFamily 4 (TM4SF4) as a potential interactor with hTHTR-2. This interaction was confirmed by an in vitro GST-pull-down assay, and by live-cell confocal imaging of HuTu-80 cells co-expressing hTHTR-2–GFP and mCherry–TM4SF4 (the latter displayed a significant overlap of these two proteins in intracellular vesicles and at the cell membrane). Co-expression of hTHTR-2 with TM4SF4 in HuTu-80 cells led to a significant induction in thiamine uptake. In contrast, silencing TM4SF4 with gene-specific siRNA led to a significant decrease in thiamine uptake.

Conclusions

These results show for the first time that the accessory protein TM4SF4 interacts with hTHTR-2 and influences the physiological function of the thiamine transporter.     

The importance of caregivers in the outcome of pediatric HIV management,Mombasa, Kenya

We assessed programmatic gaps that prevent the optimal treatment of pediatric HIV infection despite free antiretroviral care in Kenya. Of 626 HIV-infected Kenyan children, the median age was five years, 54% were male and the mortality rate was 3.2 per 100 person-years. A total of 380 (61%) children initiated antiretroviral therapy (ART) during the study period. Among the 246 children who never started ART, 129 (52%) met the criteria for ART initiation. Immunologic failure occurred in 20% of children who received ART for >24 weeks. In multivariate analysis, immunological failure was associated with having nonimmediate relative or unrelated caregivers accompanying the child to clinic (AOR = 69.16, p = 0.008). Having ≥3 types of accompanying caregivers was also associated with virologic failure in multivariate analysis (AOR = 3.84, p = 0.03). The lost to follow-up rate was 8.7/100 persons-years for the entire cohort, and significantly higher (17.7/100 persons-years) among children not on ART (p < 0.001). Among children who do initiate ART, those with the best treatment outcomes were those who had a limited number of close relatives as caregivers and good adherence to ART. Focus on early ART initiation and education of the right caregiver will likely improve retention and quality of pediatric HIV care in Kenya.     

Trabecular structural changes in the mandibular condyle caused by degenerative osteoarthritis: a comparative study by cone-beam computed tomography imaging

Oral Radiology - Temporomandibular osteoarthritis causes pain and loss of function. In advanced cases, it may also result in destruction of joint cartilage surfaces and bone structure. This study...     

Ablation of Breast Cancer Cells Using Trastuzumab‐Functionalized Multi‐Walled Carbon Nanotubes and Trastuzumab‐Diphtheria Toxin Conjugate

Trastuzumab (Herceptin^®) is a monoclonal antibody (mAb) for specific ablation of HER2‐overexpressing malignant breast cancer cells. Intensification of antiproliferative activity of trastuzumab through construction of immunotoxins and nano‐immunoconjugates is a promising approach for treatment of cancer. In this study, trastuzumab was directly conjugated to diphtheria toxin (DT). Also, conjugates of trastuzumab and multiwalled carbon nanotubes (MWCNT) were constructed by covalent immobilization of trastuzumab onto MWCNTs. Then, antiproliferative activity of the fusion constructs against HER2‐overexpressing SK‐BR‐3 and also HER2‐negative MCF‐7 cancer cell lines were examined. Cells treated with trastuzumab‐MWCNT conjugates were irradiated with near‐infrared (NIR) light. Efficient absorption of NIR radiation and its conversion to heat by MWCNTs can be resulted to thermal ablation of cancerous cells. Our results strongly showed that both trastuzumab‐MWCNT and trastuzumab‐DT conjugates were significantly efficient in the specific killing of SK‐BR‐3 cells. Targeting of MWCNTs to cancerous cells using trastuzumab followed by exposure of cells to NIR radiation was more efficient in repression of cell proliferation than treatment for cancer cells with trastuzumab‐DT. Our results also showed that conjugation linkers can significantly affect the cytotoxicity of MWCNT‐immunoconjugates. In conclusion, our data demonstrated that trastuzumab‐MWCNT is a promising nano‐immunoconjugate for killing of HER2‐overexpressing cancerous cells.     

EAACI Food Allergy and Anaphylaxis Guidelines: managing patients with food allergy in the community

The European Academy of Allergy and Clinical Immunology (EAACI) Food Allergy and Anaphylaxis Guidelines, managing patients with food allergy (FA) in the community, intend to provide guidance to reduce the risk of accidental allergic reactions to foods in the community. This document is intended to meet the needs of early‐childhood and school settings as well as providers of non‐prepackaged food (e.g., restaurants, bakeries, takeaway, deli counters, and fast‐food outlets) and targets the audience of individuals with FA, their families, patient organizations, the general public, policymakers, and allergists. Food allergy is the most common trigger of anaphylaxis in the community. Providing children and caregivers with comprehensive information on food allergen avoidance and prompt recognition and management of allergic reactions are of the utmost importance. Provision of adrenaline auto‐injector devices and education on how and when to use these are essential components of a comprehensive management plan. Managing patients at risk of anaphylaxis raises many challenges, which are specific to the community. This includes the need to interact with third parties providing food (e.g., school teachers and restaurant staff) to avoid accidental exposure and to help individuals with FA to make safe and appropriate food choices. Education of individuals at risk and their families, their peers, school nurses and teachers as well as restaurant and other food retail staff can reduce the risk of severe/fatal reactions. Increased awareness among policymakers may improve decision‐making on legislation at local and national level.