Femtometer atomic displacement, the root cause for multiferroic behavior of CuO unearthed through polarized Raman spectroscopy.

Recently, CuO has been proposed as a potential multiferroic material with high transition temperature. Competing models based on spin current and ionic displacements are invoked to explain ferroelectricity in CuO. The theoretical model based on ionic displacement predicted very small displacement (∼10-5Å) along thebaxis. Experimentally detecting displacements of such a small amplitude in a particular direction is extremely challenging. Through our detailed angle resolved polarized Raman spectroscopy study on single crystal of CuO, we have validated the theoretical study and provided direct evidence of displacement along thebaxis. Our study provides important contribution in the high temperature multiferroic compounds and showed for the first time, the use of the polarized Raman scattering in detecting ionic displacements at the femtometer scale.

Donor height in combination with islet donor score improves pancreas donor selection for pancreatic islet isolation and transplantation.

To maximize the islet isolation yield for successful islet transplantation, the key task has been to identify an ideal pancreas donor. Since implementation of the islet donor score in donor selection, we have consistently obtained higher islet yields and transplantation rates. In this study, we tested whether assessing donor height as an independent variable in combination with the donor score could improve the pancreas donor selection. Donor and islet isolation information (n = 22) were collected and studied between 2011 and 2012. Pearson correlation analysis was used in statistical analysis. Donor height as an independent variable was significantly correlated to the weight of the pancreas, pre-Islet Equivalents (pre-IEQ), post-IEQ, and IDS (P < .05). When donor with height of 179 cm ± 3 was selected in combination with IDS > 80, the clinical islet transplantation rate reached 80%.

Evaluation of viable ß-cell mass is useful for selecting collagenase for human islet isolation: comparison of collagenase NB1 and liberase HI.

The selection of enzyme blend is critical for the success of human islet isolations. Liberase HI collagenase (Roche) was introduced in the 1990s and had been widely used for clinical islet transplantation. More recently, a blend collagenase NB1 has been rendered available. The aim of this study was to evaluate the isolation outcomes and islet quality comparing human islet cells processed using NB1 and Liberase HI. A total of 90 isolations processed using NB1 (n = 40) or Liberase HI (n = 50) was retrospectively analyzed. Islet yield, function in vitro and in vivo, cellular (including ß-cell-specific) viability and content, as well as isolation-related factors were compared. No significant differences in donor-related factors were found between the groups. There were also no significant differences in islet yields (NB1 vs. Liberase: 263,389 ± 21,550 vs. 324,256 ± 27,192 IEQ; p = n.s., respectively). The pancreata processed with NB1 showed a significantly longer digestion time (18.6 ± 0.7 vs. 14.5 ± 0.5 min, p < 0.01), lower ß-cell viability (54.3 ± 3.4% vs. 72.0 ± 2.1%, p < 0.01), ß-cell mass (93,671 ± 11,150 vs. 148,961 ± 12,812 IEQ, p < 0.01), and viable ß-cell mass (47,317 ± 6,486 vs. 106,631 ± 10,228 VßIEQ, p < 0.01) than Liberase HI. In addition, islets obtained with Liberase showed significantly better graft function in in vivo assessment of islet potency. The utilization of collagenase NB1 in human islet isolation was associated with significantly lower ß-cell viability, mass, and islet potency in vivo in our series when compared to Liberase HI, even though there was no significant difference in islet yields between the groups. Evaluation of viable ß-cell mass contained in human islet preparations will be useful for selecting enzyme blends.

Combined pancreas and en bloc kidney transplantation using a bladder patch technique from very small pediatric donors.

Very small pediatric donors are underutilized for pancreas and kidney transplantation for the fear of inadequate islet mass and higher incidence of technical complications, and the lower age limit for such donors is not well defined. We present here two cases of combined pancreas and en bloc kidney transplantation from very small pediatric donors (14 and 18 months old) to adult type 1 diabetic and uremic patients. The conventional surgical procedure for simultaneous pancreas and kidney transplantation with systemic venous and bladder exocrine drainage was successfully applied to very small organs. For both, we utilized the recently described bladder patch technique for ureteral reconstruction. One patient developed venous thrombosis (partial thrombosis of the splenic and mesenteric veins) and the other urine leak (from a midportion of the medial ureter without compromising the bladder patch) after the transplants; both were successfully managed and the patients demonstrated immediate and sustained pancreas and kidney graft functions for 12 and 2 months posttransplantation. These cases illustrate the feasibility of combined pancreas and en bloc kidney transplantation from very small pediatric donors using a bladder patch technique to avoid small ureteral anastomosis.

Antiproinflammatory effects of iodixanol (OptiPrep)-based density gradient purification on human islet preparations.

Islet isolation and purification using a continuous density gradient may reduce the volume of tissue necessary for implantation into patients, therefore minimizing the risks associated with intraportal infusion in islet transplantation. On the other hand, the purification procedure might result in a decreased number of islets recovered due to various stresses such as exposure to cytokine/chemokine. While a Ficoll-based density gradient has been widely used in purification for clinical trials, purification with iodixanol (OptiPrep) has been recently reported in islet transplant series with successful clinical outcomes. The aim of the current study was to compare the effects of the purification method using OptiPrep-based and Ficoll-based density gradients. Human islet isolations were performed using a modified automated method. After the digestion phase, pre-purification digests were divided into two groups and purified using a semiautomated cell processor with either a continuous Ficoll- or OptiPrep-based density gradient. The quantity, purity, viability, and cellular composition of islet preparations from each group were assessed. Cytokine/chemokine and tissue factor production from islet preparations after 48-h culture were also measured. Although islet purity, post-purification IEQ, islet recovery rate, FDA/PI, and fractional ß-cell viability were comparable, ß-cell mass after 48-h culture significantly improved in the OptiPrep group when compared to the Ficoll group. The production of cytokine/chemokine including IL-1ß, TNF-α, IFN-γ, IL-6, IL-8, MIP-1ß, MCP-1, and RANTES but not tissue factor from the OptiPrep group was significantly lower during 48-h culture after isolation. Each preparation contained the similar number of ductal cells and macrophages. Endotoxin level in both gradient medium was also comparable. The purification method using OptiPrep gradient media significantly reduced cytokine/chemokine production but not tissue factor from human islet preparations and improved ß-cell survival during pretransplant culture. Our results suggest that the purification method using OptiPrep gradient media may be of assistance in increasing successful islet transplantation.

Thoracoscopic treatment for spontaneous hemopneumothorax.

Spontaneous hemopneumothorax is a rare clinical entity sometimes requiring an operation in the early stage. Two patients who underwent successful video-assisted thoracic surgery (VATS) for spontaneous hemopneumothorax are presented. In both cases, the bleeding point was clearly identified, and hemostasis was easily obtained by clipping the point and placing three access ports in the usual fashion. Furthermore, the evacuation of clotted blood and resection of bulla were performed with no difficulties. The postoperative courses were smooth, and no complications occurred, although the preoperative general condition in the second case was hemodynamically unstable. The advantages of VATS over conventional thoracotomy include less time required to access the pleural cavity, a better view, and more facilitated manipulation during surgery. Because spontaneous hemopneumothorax is a benign disease, VATS should be considered an initial treatment option in all patients with this condition, even those with active bleeding.

Infiltration of neutrophils following injection of apoptotic cells into the peritoneal cavity.

It has been assumed that apoptosis leads to no production of pro-inflammatory cytokines or the production of anti-inflammatory cytokines in vivo, although the response of macrophages following phagocytosis of apoptotic cells in vivo has not been examined. In this study we therefore examined the response to apoptotic cells in vivo. Injection of apoptotic cells into the peritoneal cavity of mice led to transient neutrophil infiltration and concomitant production of MIP-2, a mouse homologue of IL-8. Apoptotic cells were phagocytosed by macrophages, as revealed on two-color flow cytometric analysis and microscopic observation. When the mice were depleted of macrophages by pretreatment with liposome-encapsulated dichloromethylene bisphosphonate, both neutrophil infiltration and MIP-2 production were significantly suppressed, suggesting that macrophages are required for MIP-2 production in this in vivo response. These results support the hypothesis that extensive apoptosis occurring rapidly may induce an inflammatory response in vivo.