Low-dose radiotherapy for COVID-19 pneumonia treatment: case report, procedure, and literature review.

Background: The COVID-19 pandemic outbreak has set the emergency services in developing countries on major alert, as the installed response capacities are easily overwhelmed by the constantly increasing high demand. The deficit of intensive care unit beds and ventilators in countries like Peru is forcing practitioners to seek preventive or early interventional strategies to prevent saturating these chronically neglected facilities.

Case Presentation: A 64-year-old patient is reported after presenting with COVID-19 pneumonia and rapidly progressing to deteriorated ventilatory function.

Impact of a SBRT/SRS longitudinal telehealth training pilot course in Latin America.

Purpose: To assess the impact of longitudinal telehealth training in stereotactic body radiation therapy (SBRT) and stereotactic radiosurgery (SRS) for clinicians in Latin America.

Materials And Methods: Professionals from two Peruvian centers received an initial SBRT/SRS on-site training course and subsequently received follow-up telehealth training (interventional group) or not (negative control arm). Twelve live video conference sessions were scheduled.

Do Factors from Admissions and Dental School Predict Performance on National Board Exams? A Multilevel Modeling Study.

The aim of this study was to assess the association among admissions variables, dental school performance, and licensing exam performance for six cohorts of graduates of one dental school. Data from all dental school graduates of Schulich School of Medicine & Dentistry, Western University, Canada, from 2009 to 2014 who had matching National Dental Examining Board of Canada (NDEB) data (N=298) were analyzed. In the results, significant differences between cohorts were found on both the NDEB objective structured clinical examination (OSCE) and written scores.

Guidelines from the Canadian Association of Pathologists for establishing a telepathology service for anatomic pathology using whole-slide imaging.

The use of telepathology for clinical applications in Canada has steadily become more attractive over the last 10 years, driven largely by its potential to provide rapid pathology consulting services throughout the country regardless of the location of a particular institution. Based on this trend, the president of the Canadian Association of Pathologists asked a working group consisting of pathologists, technologists, and healthcare administrators from across Canada to oversee the development of guidelines to provide Canadian pathologists with basic information on how to implement and use this technology. The guidelines were systematically developed, based on available medical literature and the clinical experience of early adopters of telepathology in Canada.

Memory T Cells Mediate Cardiac Allograft Vasculopathy and are Inactivated by Anti-OX40L Monoclonal Antibody.

Purpose: Cardiac allograft vasculopathy (CAV) is a major complication limiting the long-term survival of cardiac transplants. The role of memory T cells (Tmem) in the pathogenesis of CAV remains elusive. This study investigated the role of Tmem cells in the development of CAV and the therapeutic potential of targeting the OX40/OX40L pathway for heart transplant survival.

Carbon monoxide releasing molecules inhibit cell death resulting from renal transplantation related stress.

Purpose: Organ cold storage and subsequent transplantation are associated with significant ischemia-reperfusion injury, leading to cell death, graft inflammation and decreased graft function.

Materials And Methods: CORM-3s reduce oxidative stress and prevent inflammation in kidneys stored at 4C and subsequently transplanted. Graft survival and function are markedly improved compared to kidneys preserved and stored in University of Wisconsin solution alone.

Supplemental hydrogen sulphide protects transplant kidney function and prolongs recipient survival after prolonged cold ischaemia-reperfusion injury by mitigating renal graft apoptosis and inflammation.

Unlabelled: What's known on the subject? and What does the study add? Hydrogen sulphide (H(2) S) has recently been classified as a member of the family of small gaseous molecules called gasotransmitters and has been found to have many important physiological functions. Several recent studies have elucidated the protective effects of H(2) S in many models of tissue ischaemia-reperfusion injury (IRI), including hepatic, myocardial, pulmonary, cerebral and renal IRI. It has previously been shown that H(2) S has a number of properties that may contribute to its protection against IRI, including vasodilatory, anti-apoptotic, anti-inflammatory and anti-oxidant effects, although the specific actions appear to vary between tissues.

Costimulation blockade in pig artery patch xenotransplantation - a simple model to monitor the adaptive immune response in nonhuman primates.

Background: CD154 blockade-based immunosuppression successfully prevents both humoral and cellular adaptive immune responses in baboons receiving α1,3-galactosyltransferase gene-knockout (GTKO) pig organs. Using a GTKO pig artery transplantation model in baboons, we evaluated the efficacy of CD28/B7 costimulatory pathway blockade in comparison with CD154 blockade.

Methods: Baboons received artery patch grafts from GTKO pigs, with no (Group1), anti-CD154mAb-based (Group2), or CTLA4-Ig-based (Group3) immunosuppressive therapy.

Effect of an angiogenesis inhibitor on hepatic tumor perfusion and the implications for adjuvant cytotoxic therapy.

Purpose: To determine whether dynamic contrast material-enhanced (DCE) computed tomography (CT) can help identify hepatic tumor perfusion response to vascular remodeling induced by antiangiogenesis treatment in a rabbit model.

Materials And Methods: The study was approved by the Animal Use Subcommittee of the University Council on Animal Care. DCE CT hepatic perfusion measurements were performed in the livers of 20 rabbits implanted with VX2 carcinoma.

Familial papillary thyroid carcinoma: a retrospective analysis.

Background. Whether or not the familial form of papillary thyroid carcinoma is more aggressive than the sporadic form of the disease remains controversial. Methods.

Carbon monoxide-releasing molecules protect against ischemia-reperfusion injury during kidney transplantation.

Carbon monoxide (CO) can provide beneficial antiapoptotic and anti-inflammatory effects in the context of ischemia-reperfusion injury (IRI). Here we tested the ability of pretreating the kidney donor with carbon monoxide-releasing molecules (CORM) to prevent IRI in a transplant model. Isogeneic Brown Norway donor rats were pretreated with CORM-2 18 h before kidney retrieval.

Anti-IL-2 receptor antibody decreases cytokine-induced apoptosis of human renal tubular epithelial cells (TEC).

Background: Transplant rejection is mediated by T-cell activation which is modulated by interleukin-2 (IL-2) binding to IL-2R (CD25). Monoclonal anti-IL-2 receptor antibody is used in renal transplantation to reduce rejection. Interestingly, proximal tubular epithelial cells (TEC) express CD25, similar to T cells.

Prevention of chronic renal allograft rejection by soluble CD83.

Background: Recombinant human soluble CD83 had previously exhibited significant immunosuppressive properties that involved interference with dendritic cell maturation in both mouse and humans, inhibition of autoimmunity in mice, and induction of antigen-specific mouse cardiac allograft tolerance when used in combination with other immunosuppressive drugs. Our current research focus turned to examining the effects of peritransplant soluble CD83 (sCD83) administration on prevention of chronic renal allograft rejection.

Methods: Fisher344-to-Lewis orthotopic rat renal transplants were performed with sequential recipient killing on postoperative days (PODs) 2, 14, and 140 to examine both the acute and chronic effects of peritransplant sCD83 treatment in rat recipients.

Induction of kidney allograft tolerance by soluble CD83 associated with prevalence of tolerogenic dendritic cells and indoleamine 2,3-dioxygenase.

Background: Tolerogenic dendritic cells (Tol-DCs) play a critical role in inducing and maintaining tolerance. Recognizing that both T-cell inactivation and activation are contingent on signals provided by DCs and that graft-specific activated T cells are major mediators of transplant rejection, we aimed to create an environment favoring Tol-DCs with a novel reagent, human soluble CD83 (hsCD83).

Methods: Life-supporting orthotopic kidney transplantation was performed in a C57BL/6-to-BALB/c mouse model.

Adoptive transfer of DNT cells induces long-term cardiac allograft survival and augments recipient CD4(+)Foxp3(+) Treg cell accumulation.

Regulatory T (Treg) cells play an important role in the regulation of immune responses but whether Treg will induce tolerance in transplant recipients in the clinic remains unknown. Our previous studies have shown that TCRαβ(+)CD3(+)CD4⁻CD8⁻NK1.1⁻ (double negative, DN) T cells suppress T cell responses and prolong allograft survival in a single locus MHC-mismatched mouse model.

Regulatory T-cell generation and kidney allograft tolerance induced by mesenchymal stem cells associated with indoleamine 2,3-dioxygenase expression.

Background: The immunoregulatory properties of mesenchymal stem cells (MSCs) have been observed in vitro and in vivo. However, the underlying mechanisms of this immunomodulation remain undefined. Recent research demonstrated that MSCs express the tryptophan-catabolizing enzyme indoleamine 2,3-dioxygenase (IDO), known to suppress T-cell responses.

Immunosuppression involving soluble CD83 induces tolerogenic dendritic cells that prevent cardiac allograft rejection.

Background: Dendritic cells (DCs) are crucial regulators of immunity and important in inducing and maintaining tolerance. Here, we investigated the potential of a novel DC-immunomodulating agent, soluble CD83 (sCD83), in inducing transplant tolerance.

Methods: We used the C3H-to-C57BL/6 mouse cardiac transplantation model that exhibits a combination of severe cell-mediated rejection and moderate antibody-mediated rejection and investigated whether sCD83 could augment a combination therapy consisting of Rapamycin (Rapa) and anti-CD45RB monoclonal antibody (α-CD45) to prolong allograft survival.

Osteopontin expressed in tubular epithelial cells regulates NK cell-mediated kidney ischemia reperfusion injury.

Renal ischemia reperfusion injury (IRI) occurs after reduced renal blood flow and is a major cause of acute injury in both native and transplanted kidneys. Studies have shown diverse cell types in both the innate and the adaptive immune systems participate in kidney IRI as dendritic cells, macrophages, neutrophils, B cells, CD4(+) NK(+) cells, and CD4(+) T cells all contribute to this form of injury. Recently, we have found that NK cells induce apoptosis in tubular epithelial cells (TECs) and also contribute to renal IRI.

Treatment of autoimmune arthritis using RNA interference-modulated dendritic cells.

Dendritic cells (DCs) have a dual ability to either stimulate or suppress immunity, which is primarily associated with the expression of costimulatory molecules. Ag-loaded DCs have shown encouraging clinical results for treating cancer and infectious diseases; however, the use of these cells as a means of suppressing immune responses is only recently being explored. Here, we describe the induction of RNA interference through administering short interfering RNA (siRNA) as a means of specifically generating tolerogenic DCs.

A novel allergen-specific therapy for allergy using CD40-silenced dendritic cells.

Background: Induction of RNA interference with small interfering RNA (siRNA) has demonstrated therapeutic potential through the knockdown of target genes. We have previously reported that systemic administration of CD40 siRNA is capable of attenuating allergic symptoms but in an allergen-nonspecific fashion. However, siRNA-based allergen-specific therapy for allergy has not been developed.

RNAi-mediated CD40-CD154 interruption promotes tolerance in autoimmune arthritis.

Introduction: We have previously demonstrated that ex vivo inhibition of costimulatory molecules on antigen-pulsed dendritic cells (DCs) can be useful for induction of antigen-specific immune deviation and suppression of autoimmune arthritis in the collagen induced arthritis (CIA) model. The current study evaluated a practical method of immune modulation through temporary systemic inhibition of the costimulatory molecule CD40.

Methods: Mice with collagen II (CII)-induced arthritis (CIA) were administered siRNA targeting the CD40 molecule.

The National Oncology Program: a Yemeni-Canadian partnership.

Cancer in developing countries is growing and will soon be a major problem as life expectancy increases. This article outlines the experience and future objectives of a partnership between Yemeni and Canadian oncology professionals in their attempt to develop a National Oncology Program in Yemen. We review current knowledge of the epidemiology, social, educational and economic challenges as well as suggested initial steps in developing a relevant oncology program for this society.

Development of techniques for gastrojejunal bypass surgery in obese mice.

We have previously described a duodenojejunal bypass (DJB) surgical model in healthy C57BL/6 mice. However, our pilot study showed that the same surgical technique caused a high mortality rate in obese mice. In this study, to significantly improve animal survival rate following bariatric surgery and thereby providing a stable surgical model for the study of glucose homeostasis in obese mice, we have used modified techniques and developed the end-to-side gastrojejunal bypass (GJB) surgery in obese C57BL/6 with impaired glucose tolerance.

Novel small interfering RNA-containing solution protecting donor organs in heart transplantation.

Background: Ischemia/reperfusion injury is a major factor in graft quality and subsequent function in the transplantation setting. We hypothesize that the process of RNA interference may be used to "engineer" a graft to suppress expression of genes associated with inflammation, apoptosis, and complement, which are believed to cause ischemia/reperfusion injury. Such manipulation of pathological gene expression may be performed by treatment of the graft ex vivo with small interfering RNA (siRNA) as part of the preservation procedure.