An explanation of renal hemodynamics in acute renal failure based on sequential CT in patients with Korean hemorrhagic fever

The pattern of renal enhancement and washout of contrast medium was observed on sequential follow-up CT in 12 patients with Korean hemorrhagic fever, in which acute renal failure is one of the most important clinical features. Renal contrast enhancement and contrast medium washout were delayed longer in patients with severe oliguric renal failure. The delayed washout peaked at 4-5 days and did not return to normal until 8-9 days in the patients with severe oliguria; in the patients without severe oliguria the times were 1-2 days and 3-4 days, respectively. A characteristic "cart-wheel" pattern was observed during the washout stage in patients without severe oliguria. This "cart-wheel" pattern of washout is thought to result from relief of vasoconstriction and repair of tubular function. Multifocal "wedge-shaped" nonenhanced areas of the kidney, seen on the 2 week follow-up postcontrast CT, are thought to be ischemic zones due to persistent vasoconstriction. On the 6 week follow-up postcontrast CT in one patient, scarring of the kidney was detected in the same area that did not enhance on the 2 week CT. This scarring is thought to be a result of permanent vasoconstriction.     

Waning Antibody Responses in Asymptomatic and Symptomatic SARS-CoV-2 Infection

We investigated the kinetics of severe acute respiratory syndrome coronavirus 2 neutralizing antibodies in 7 asymptomatic persons and 11 patients with pneumonia. The geometric mean titer of neutralizing antibodies declined from 219.4 at 2 months to 143.7 at 5 months after infection, indicating a waning antibody response.     

Clinical Significance of De Novo Malignancy After Liver Transplant: A Single-Center Study

BackgroundSeveral studies have reported that solid organ transplant recipients have a high risk for malignant tumors because the suppressed immune system fails in preventing malignant transformations. De novo malignancy after transplantation is the most common cause of death in the late period after liver transplant (LT). This study investigated the clinical significance of de novo malignancy after LT, and it is the largest study based in Korea to report long-term follow-up results associated with de novo malignancy after LT.MethodsData of 1793 adults who underwent LT in Seoul National University Hospital were retrospectively collected, and medical charts and data from the Ministry of Public Administration and Security were reviewed to examine the causes of death and de novo malignancy status. The Fisher exact test and Kaplan-Meier survival analysis were used to analyze the data.ResultsOf the 1793 recipients, 27 died of de novo malignancies. Of 875 hepatocellular carcinoma (HCC) patients, 12 died, and of 918 non-HCC patients, 15 died. De novo malignancy was the main cause of death at 5 years after LT but was not in the initial 5 years. In Korea the most common cancers that developed after LT were gastric cancer (21.4%) and lymphoma (14.3%). De novo HCC in non-HCC cases was found in 2 patients.ConclusionDe novo malignancy is a key factor affecting long-term survival after LT. Therefore, regular screening and education are important for improving long-term survival and quality of life in these patients after LT.     

The influence of preoperative carbohydrate loading on postoperative outcomes in bariatric surgery patients: a randomized,controlled trial

BackgroundPreoperative carbohydrate loading is a component of Enhanced Recovery After Surgery (ERAS) protocols, but there is limited literature in bariatric surgery patients.ObjectivesThe objective of this study was to characterize the impact of preoperative carbohydrate loading on postoperative bariatric surgery outcomes.SettingUniversity Hospital.MethodsPatients undergoing a primary minimally invasive Roux-en-Y gastric bypass (RYGB) or sleeve gastrectomy (SG) between 2018 and 2020 were randomized to standard management or intervention. Standard management patients were nothing by mouth (NPO) after midnight prior to surgery. Intervention patients consumed 2 carbohydrate drinks: 1 the night before and another 3 hours prior to surgery. Primary outcomes analyzed included postoperative nausea and vomiting (PONV), length of stay, and overall complications.ResultsIn total, 134 patients were analyzed: 64 intervention (47.8%) and 70 (52.2%) standard. In the end, 7% and 15% of patients were lost to follow-up at 6-weeks and 3-months, respectively. There was no statistically significant difference in length of stay (2.0 ± 1.2 vs 2.1 ± .9 d; P = .65) or postoperative outcomes between the 2 groups. There were no episodes of aspiration among the intervention group. Among RYGB patients, intervention patients had a shorter duration of nausea compared with standard patients. There was no significant difference in glycemic control among patients with and without diabetes.ConclusionsPreoperative carbohydrate drinks can be administered to bariatric surgery patients without significant risks. Carbohydrate loading preoperatively can decrease the duration of PONV in RYGB patients. Carbohydrate drinks can be safely included in bariatric ERAS protocols for patients with and without diabetes, although the benefits remain unknown.     

Short-term therapy with anti-ICAM-1 monoclonal antibody induced long-term liver allograft survival in nonhuman primates

Tolerance induction remains challenging following liver transplantation and the long-term use of immunosuppressants, especially calcineurin inhibitors, leads to serious complications. We aimed to test an alternative immunosuppressant, a chimeric anti-ICAM-1 monoclonal antibody, MD-3, for improving the outcomes of liver transplantation. We used a rhesus macaque liver transplantation model and monkeys were divided into three groups: no immunosuppression (n = 2), conventional immunosuppression (n = 4), and MD-3 (n = 5). Without immunosuppression, liver allografts failed within a week by acute rejection. Sixteen-week-long conventional immunosuppression that consisted of prednisolone, tacrolimus, and an mTOR inhibitor prolonged liver allograft survival; however, recipients died of acute T cell–mediated rejection (day 52), chronic rejection (days 62 and 66), or adverse effects of mTOR inhibitor (day 32). In contrast, 12-week-long MD-3 therapy with transient conventional immunosuppression in the MD-3 group significantly prolonged the survival of liver allograft recipients (5, 96, 216, 412, 730 days; p = .0483). MD-3 effectively suppressed intragraft inflammatory cell infiltration, anti-donor T cell responses, and donor-specific antibody with intact anti-cytomegalovirus antibody responses. However, this regimen ended in chronic rejection. In conclusion, short-term therapy with MD-3 markedly improved liver allograft survival to 2 years without maintenance of immunosuppressant. MD-3 is therefore a promising immune-modulating agent for liver transplantation.     

GAG-augmented polysaccharide hydrogel: a novel biocompatible and biodegradable material to support chondrogenesis

The quality of articular cartilage engineered using a cell-polymer construct depends, in part, on the chemical composition of the biomaterial and whether that biomaterial can support the chondrocytic phenotype. Acknowledging the supportive influence of tissue-specific matrix molecules on the chondrocytic phenotype, we have combined chondroitin sulfate-A (CSA) and chitosan, a glycosaminoglycan (GAG) analog, to develop a novel biomaterial to support chondrogenesis. Chitosan is a polycationic repeating monosaccharide of beta-1,4-linked glucosamine monomers with randomly located N-acetyl glucosamine units. Chitosan may be combined with the polyanionic CSA such that ionic crosslinking results in hydrogel formation. Bovine primary articular chondrocytes, when seeded onto a thin layer of CSA-chitosan, form discrete, focal adhesions to the material and maintain many characteristics of the differentiated chondrocytic phenotype, including round morphology, limited mitosis, collagen type II, and proteoglycan production. Our findings suggest CSA-chitosan may be well suited as a carrier material for the transplant of autologous chondrocytes or as a scaffold for the tissue engineering of cartilage-like tissue.     

A case of leukemia-associated arthritis--identification of leukemic cells in synovial fluid by light microscopy

One case of arthritis complicating leukemia is described in which leukemic cells were identified in synovial fluid by light microscopy. Although arthritis is a well-known manifestation of leukemia with an incidence of 13.5%, the pathogenesis often is unclear, and the direct demonstration of leukemic cells in synovial fluid has been very uncommon. A 16 year-old male patient was admitted due to left elbow joint pain and swelling. Synovial fluid examination revealed blast cells and this finding has directed to a final diagnosis of acute lymphoblastic leukemia.     

Induction of apoptosis in HepG2 human hepatocellular carcinoma cells by a novel derivative of ursodeoxycholic acid (UDCA)

The effects of ursodeoxycholic acid (UDCA) and its novel derivative, named as HS-1030, on the proliferation of HepG2, human hepatocellular carcinoma cells were investigated. Whereas UDCA had no significant effect in a concentration range we have tested, HS-1030 inhibited the proliferation of HepG2 cells in a concentration dependent manner. Surprisingly, HS-1030 had no effect on the proliferation of Human Chang liver cell which is a normal liver cell line. We also found that proliferation-inhibitory effect of HS-1030 was due to the induction of apoptosis of HepG2 cells, which was confirmed by observing the internucleosomal DNA fragmentation and morphological changes (i.e. cell shrinkage, nuclear condensation and the formation of apoptotic bodies). These results suggest that HS-1030 may be a good candidate as a drug for the treatment of liver cancer.     

Preclinical evaluation of prototype products

Preclinical evaluation of medical devices (prototype products) offers the opportunity to investigate and study the intended use of device materials. Preclinical evaluation programs are designed to determine the efficacy, safety, and biocompatibility of biomaterials, prostheses, and medical devices. The purpose of safety testing is to determine if a material presents potential harm to the human; it evaluates the interaction of the material with the in vivo environment and determines the effect of the host on the implant. Preclinical evaluation is the determination of the ability of the prototype product to perform with appropriate host response in a specific application, considered from the perspective of human clinical use. Therefore, preclinical data should include materials science and engineering, biology, biochemistry, medicine, host reactions and their evaluation, the testing of biomaterials, and the degradation of materials in a biological environment.