A bolus of saline injection leads to increase in coronary flow based on the viscosity reduction effect: the mechanism of saline induced Pd/Pa ratio

Background

In conjunction with fractional flow reserve (FFR), our previous study has shown the accuracy and utility of saline induced Pd/Pa ratio (SPR) for the assessment of myocardial ischemia. However, the potential mechanism how saline injection leads to increase in coronary flow remains speculative.

Purpose

This study aimed to clarify the underlying mechanism of SPR by using swine models.

Methods

The study was conducted in four swine models, and bolus of 25°C saline, 40°C saline, and 25°C dextran was injected at rates of 40mL/5sec through a catheter inserted into the superior mesenteric artery. Its peripheral arterioles were observed and recorded by a digital microscope, and transit time of each fluid and a luminal diameter of arterioles before and after injection were measured.

Results

The result from arterioles diameters of pre- and post-injection (0.049±0.016mm vs. 0.050±0.016mm; P=0.636) indicated that luminal diameters remained unchanged regardless of fluid administration. The transit time of 25°C saline was significantly shorter than 25°C dextran (3.19±0.68sec vs. 6.15±1.19sec; P<0.0001). Although the result showed no significance, the transit time of 40°C saline with lower viscosity was shorten compared to 25°C saline (3.1±0.43sec vs. 3.65±0.46sec; P=0.088).

Conclusions

Compared to 25°C dextran (viscosity of 4.991mPa·s) having the same viscosity as 37°C whole blood, 25°C saline (viscosity of 1.012mPa·s) caused increasing to double the intravascular flow volume without dilating arterioles. The results strongly suggested that the potential mechanism of SPR was viscosity reduction effect. Combined with FFR which is based on vasodilation-mediated hyperemia, these findings may contribute to clarifying the pathophysiology and especially the microcirculation in coronary artery diseases.

Funding Acknowledgement

Type of funding source: None

The developing mechanism of atherosclerotic lesion in coronary side branch on the ventricular free wall differs by the location of lesion

Background

The effective treating method of coronary side branch lesions such as ostial stenosis or thin arteries has not been established. On the other hand, tortuous side branch rarely has stenotic lesions.

Purpose

We focused on coronary side branches on the ventricular free wall, and examined coronary risk factors and bending and stretching motion of branch which can contribute to the development of atherosclerotic lesion.

Methods

In elective and first-time coronary angiograms, we included side branches on the ventricular free wall (>2mm in diameter) and excluded previously treated ones. Study A; we divided arteries into proximal, middle, and distal segment, and examined the presence of tortuosity and stenotic lesions exceeding 50% diameter stenosis (DS) for each segment. A score of 1 was assigned to tortuous segment, and 0 to non-tortuous one. Study B; we included stenotic lesion (>50% DS) in side branch ostium and excluded those extended across main coronary arteries. Relation between lesions and patients' characteristics was examined.

Results

Study A; in 1,828 side branches from 472 patients, middle and distal segments had significantly higher tortuosity score than proximal (0.68, 0.78 vs. 0.34; p<0.0001). On the contrary, proximal segments had more stenotic lesions except ostial stenosis (230 vs. 69, 5; p<0.0001). Study B; in 1,740 side branches from 465 patients, 122 ostial stenotic lesions were found (7.0%). Multivariate logistic regression analysis revealed diabetes mellitus and age as independent contributors to development of ostial stenosis (Table).

Conclusions

Side branch stenosis developed less frequently in middle and distal segments, where stronger ventricular wall motion reinforces bending and stretching motion and tortuosity of arteries. This fact indicates that those characteristics may prevent developing atherosclerosis through increasing shear stress. On the other hand, diabetes mellitus strongly contributes to the development of ostial stenosis. Thus, the developing mechanism of atherosclerotic lesion in side branch on the ventricular free wall differs by the location of lesion.

Funding Acknowledgement

Type of funding source: None

Lower geriatric nutritional risk index predicts postoperative pancreatic fistula in patients with distal pancreatectomy

Postoperative pancreatic fistula (POPF) is a common complication following pancreatic resection. It leads to increased medical costs, and longer hospital stays. However, the risk factors of POPF are still unclear, and therefore, this urgent clinical issue should be resolved. The geriatric nutritional risk index (GNRI) is tool to assess the nutritional status using body weight, and serum albumin value, particularly in elderly patients. On the other hand, POPF is associated with body mass index (BMI). Thus, the present study aimed to investigate whether GNRI can predict the risk of POPF in patients after distal pancreatectomy (DP). We conducted a retrospective cohort study involving 37 patients who were treated at the Department of Digestive Surgery, Kawaguchi Municipal Medical Center between January 2007 and June 2018. All patients were subjected to nutritional screening using GNRI, and were followed up after DP for postoperative complications including POPF. In addition, risk factors of POPF, and patient's height, BMI, and preoperative laboratory values were analyzed. POPF was observed in 7 of the 37 (19%) patients. Those with a POPF had significantly lower GNRI values than those without POPF (P<0.001). Receiver operating characteristic curve analysis was performed to determine a cut-off value of GNRI, which indicated an increased risk of POPF. This value was determined as 96 (sensitivity: 71.4%, specificity: 86.7%, likelihood ratio: 5.36). Univariate analysis confirmed that a GNRI of <96 was significantly associated with POPF (P=0.005), and a multivariate logistic regression analysis revealed that a GNRI of <96 was significant independent predictor of POPF (P=0.005), suggesting its utility for assessing the risk of POPF following DP.

[Intra-Abdominal Desmoid Tumor in a Young Man without Laparotomy History-A Case Report]

During a follow-upstudy after the treatment of T cell lymphoma, a 21-year-old man reported an intra-abdominal mass in his right lower abdomen, which was then confirmed using abdominal CT. Therefore, recurrence was suspected due to his medical history. To perform a biopsy, laparoscopic surgery was scheduled, which located the tumor in the mesentery of the terminal ileum, involving the cecum. For this, laparoscopic ileocecal resection was performed. After 7 days, the patient was discharged without complications. Histopathologically, the mass was diagnosed as a desmoid tumor via immunostaining. It is relatively rare that an intra-abdominal desmoid tumor occurs without risk factors in a young man. We herein report a case of an intra-abdominal desmoid tumor, which was successfully treated using laparoscopic surgery.

[A Case of Ampullary Region Carcinoma in a Young Woman - A Case Report]

A 19-year-old woman with general fatigue who initially consulted a local hospital was referred to us for further examination of jaundice. Contrast-enhanced CT revealed apparent dilatation of the bile duct. Gastrointestinal endoscopy exhibited a tumor of the papilla of Vater(adenocarcinoma, tub2). Thus, pylorus-preserving pancreatoduodenectomy with D2 lymph node dissection was performed. Pathologically, she was diagnosed with a T3bN1M0, pStage ⅡB tumor. After surgery, the patient underwent adjuvant chemotherapy containing S-1 for 6 months. We herein report a juvenile case of ampullary region carcinoma that was successfully treated.

Intestinal obstruction caused by primary adenosquamous cell carcinoma of the small intestine: A case report and review of the literature

Primary adenosquamous cell carcinoma (ASCC) arising from the ileum is an exceptionally rare malignant neoplasm exhibiting mixed glandular and squamous differentiation. The clinicopathological characteristics of ASCC have not been clearly determined due to its rarity. We herein report a case of a 74-year-old man with a successfully treated ASCC of the ileum. The patient visited a medical clinic due to abdominal pain. Abdominal computed tomography imaging revealed an intestinal tumor in the ileum. Prior to undergoing capsule endoscopy, the patient complained of severe abdominal pain due to intestinal obstruction from the patency capsule and the tumor. Thus, the patient was referred to our hospital for emergency surgery. Upon relieving the obstruction by partial resection of the ileum, an impacted patency capsule with a tumor with ulceration was identified. On histological examination, the tumor consisted of malignant glandular and squamous cell elements. The postoperative course was uneventful, without complications. The patient subsequently received adjuvant chemotherapy with oxaliplatin and capecitabine for 6 months. The patient has no evidence of recurrence 20 months after surgery. To the best of our knowledge, only 8 cases of ASCC have been reported in the English literature to date. This case serves as an important reminder to consider small intestinal carcinoma, including ASCC, in the differential diagnosis of intestinal obstruction.

[Curatively Resected Stage ⅣGastric Cancer with Positive Peritoneal Cytology Due to SOX Therapy-A Case Report]

A 70-year-old man with epigastralgia who initially visited a local hospital was referred to us for further examination. Gastrointestinal endoscopy exhibited a type 3 tumor of the stomach from the body to the antrum(adenocarcinoma, por1). Contrast-enhanced CT revealed thickness in the wall of the gastric body with bulky lymph nodes and ascites. Staging laparoscopy showed that the patient was diagnosed with sStage Ⅳ gastric cancer with positive peritoneal cytology. Therefore, SOX therapy was administered. Subsequently, total gastrectomy with D2 lymph node dissection was performed, since the primary tumor and lymph nodes were significantly reduced. Histopathologically, the residual lesion was only observed in the mucosal layer without lymph node metastases. We herein report a case of Stage Ⅳ gastric cancer, which was successfully treated by conversion surgery after SOX therapy.

Effectiveness of Preceding Solo Kidney Transplantation for Type 1 Diabetes With End-Stage Renal Failure

Preceding solo kidney transplantation for type 1 diabetes with end-stage renal failure is controversial because of less pancreatic graft survival in pancreas transplantation after kidney transplantation (PAK) than in simultaneous pancreas and kidney transplantation (SPK).

METHODS

To study the effectiveness of preceding solo kidney transplantation for type 1 diabetes with end-stage renal failure, comparative retrospective analysis was performed between SPK (n = 232) and PAK (n = 39) that were performed until December 2016.

RESULTS

At 1, 3, and 5 years, pancreatic graft survival in SPK was 87.5%, 86.4%, and 82.8%, respectively, and 87.1%, 65.0%, and 49.1%, respectively, in PAK, which showed lesser long-term graft survival than SPK. Because 10 cases out of 16 (62.5%) failed into pancreatic graft loss with rejection in PAK, which was about 3 times more than in SPK, control of rejection is very important; rejection episodes were decreased by rabbit antithymocyte globulin induction resulting in improved graft survival. Five-year patient survival was 88.0% in SPK and 96.6% in PAK.

CONCLUSION

Considering patient survival, preceding solo kidney transplantation for type 1 diabetes with end-stage renal failure should be performed if a donor is available.

Laparoscopy-Assisted Spleen-Preserving Distal Pancreatectomy for Living-Donor Pancreas Transplantation

BACKGROUND

Living pancreas transplantation plays an important role in the treatment of patients with severe type 1 diabetes. However, pancreatectomy is very invasive for the donor, and less-invasive surgical procedures are needed. Although some reports have described hand-assisted laparoscopic surgery for distal pancreatectomy in living-donor operations, less-invasive laparoscopy-assisted (LA) procedures are expected to increase the donor pool. We herein report the outcomes of four cases of LA spleen-preserving distal pancreatectomy (Warshaw technique [WT]) in living pancreas donors.

PATIENTS AND METHODS

Four living pancreas donors underwent LA-WT at our institution from September 2010 to January 2013. All donors fulfilled the donor criteria established by the Japan Society for Pancreas and Islet Transplantation.

RESULTS

The median donor age was 54 years. Two donors underwent left nephrectomy in addition to LA-WT for simultaneous pancreas-kidney transplantation. The median donor operation time for pancreatectomy was 340.5 minutes. The median pancreas warm ischemic time was 3 minutes. The median donor blood loss was 246 g. All recipients immediately achieved insulin independence. One donor required reoperation because of obstructive ileus resulting from a port-site hernia. Another donor developed a pancreatic fistula (International Study Group of Pancreatic Fistula grade B), which was controlled with conservative management. After a maximum follow-up of 73 months, no clinically relevant adverse events had occurred. These results were comparable with those of previous studies concerning living-donor pancreas transplantation.

CONCLUSION

The LA-WT is a safe and acceptable operation for living-donor pancreas transplantation.

Outcome of renal transplantation in patients with type 2 diabetic nephropathy: a single-center experience

BACKGROUND

Renal transplantation has been established as a treatment for end-stage renal disease (ESRD) due to diabetic nephropathy. However, few studies have focused on the outcome after renal transplantation in patients with ESRD and type 2 diabetic nephropathy. To investigate the effect of renal transplantation on ESRD with type 2 diabetic nephropathy, we retrospectively analyzed patients who received renal transplantation at our facility. This study aimed to compare the outcome of renal transplantation for type 2 diabetic nephropathy with that for nondiabetic nephropathy.

METHODS

We studied 290 adult patients, including 65 with type 2 diabetic nephropathy (DM group) and 225 with nondiabetic nephropathy (NDM group), who underwent living-donor renal transplantation at our facility from February 2008 to March 2013. We compared the 2 groups retrospectively.

RESULTS

In the DM and NDM groups, the 5-year patient survival rates were 96.6% and 98.7%, and the 5-year graft survival rates were 96.8% and 98.0%, respectively, with no significant differences between the groups. There were no significant differences in the rates of surgical complications, rejection, and infection. The cumulative incidence of postoperative cardiovascular events was higher in the DM group than in the NDM group (8.5% vs 0.49% at 5 years; P = .002).

CONCLUSIONS

Patient and graft survival rates after renal transplantation for type 2 diabetic nephropathy are not inferior to those for recipients without diabetic nephropathy. Considering the poor prognosis of patients with diabetic nephropathy on dialysis, renal transplantation can provide significant benefits for these patients.

Impact of flow cytometry crossmatch B-cell positivity on living renal transplantation

BACKGROUND

Various studies have reported poorer graft survival among individuals displaying T-cell-positive flow cytometry crossmatches (FCXM). Good outcomes have been observed in immunologically high-risk patients with the use of rituximab, plasmapheresis, and γ-globulin. Because the relevance of FCXM B-cell-positivity (BCXM (+)) alone remains controversial, we examined its impact on living donor renal transplantations.

PATIENTS AND METHODS

We retrospectively studied 146 adult renal transplantation recipients from April 2007 to June 2012, dividing the patients into BCXM (+) (n = 31) versus BCXM (-) recipients (n = 115). We examined patient and graft survivals as well as rejection rates at 0 to 3, 3 to 12, and 12 to 24 months. We also determined the incidence of infectious diseases. We performed stepwise multivariate regression to identify risk factors contributing rejection episodes.

RESULTS

One-year patient and graft survivals were 100% in both groups. The BCXM (-) group have a 16.8% rejection probability whereas the BCXM (+) group, 33.2% (P = .201). There were no significantly differences in the incidence of infectious diseases. Only the rate of a sensitizing history was an independent risk factor for a rejection episode.

CONCLUSION

BCXM (+) showed only a tendency but not a significant impact on rejection episodes compared with BCXM (-); short-term graft survivals were similar.

Decontamination of outdoor school swimming pools in Fukushima after the nuclear accident in March 2011

Because of radioactive fallout resulting from the Fukushima Daiichi Nuclear Power Plant (NPP) accident, water discharge from many outdoor swimming pools in Fukushima was suspended out of concern that radiocesium in the pool water would flow into farmlands. The Japan Atomic Energy Agency has reviewed the existing flocculation method for decontaminating pool water and established a practical decontamination method by demonstrating the process at eight pools in Fukushima. In this method, zeolite powder and a flocculant are used for capturing radiocesium present in pool water. The supernatant is discharged if the radiocesium concentration is less than the targeted level. The radioactive residue is collected and stored in a temporary storage space. Radioactivity concentration in water is measured with a NaI(Tl) or Ge detector installed near the pool. The demonstration results showed that the pool water in which the radiocesium concentration was more than a few hundred Bq L was readily purified by the method, and the radiocesium concentration was reduced to less than 100 Bq L. The ambient dose rates around the temporary storage space were slightly elevated; however, the total increase was up to 30% of the background dose rates when the residue was shielded with sandbags.

Laparoscopic splenectomy using pneumoperitoneum or gasless abdominal wall lifting: a 15-year single institution experience

INTRODUCTION

Laparoscopic splenectomy using pneumoperitoneum has been performed since 1992. The gasless abdominal wall-lifting method for laparoscopic splenectomy was introduced as an alternative. This retrospective study was undertaken to compare results using the two techniques.

METHODS

Between 1995 and 2010, 54 patients underwent laparoscopic splenectomy at a single institution; 30 underwent the procedure using the gasless technique and 24 using pneumoperitoneum. There were no significant differences between the two groups regarding age, sex or BMI, but more patients underwent concurrent operations in the pneumoperitoneum group. The abdominal wall-lift system with subcutaneous K-wires was used for the gasless method.

RESULTS

Intraoperative blood loss was similar in the two groups (193.0 ± 196.7 mL gasless, 217.3 ± 296.6 mL pneumoperitoneum; P > 0.05), but operative time (182.1 ± 92.1 min, 135.1 ± 46.1 min; P < 0.05), and resected spleen weight (306.1 ± 297.7 g, 138 ± 81.0 g; P < 0.05) were significantly different. In the gasless group, additional procedures included conversion (n = 1), mini-laparotomy (n = 2), and CO(2) insufflation (n = 2). Excluding the concurrent living-related kidney donor patients, hospital stay was similar (6.9 ± 2.5 days, 6.3 ± 2.0 days, P > 0.05).

CONCLUSION

Although gasless laparoscopic splenectomy is feasible, there are disadvantages, particularly the restricted operative working space in some patients. These results suggest that either technique may be used on an individual basis in patients undergoing laparoscopic splenectomy.

Effects of O2 Gas Addition on Diamond-Like Carbon Film Deposition

The role of 02 gas addition on the deposition of Diamond-like Carbon (DLC) film was studied for hard disk drive (HDD) media application. The influence of 02 gas mixing ratio on DLC film quality was investigated using the dc magnetron sputtering method with a solid graphite target and Ar, CH4 and 02 mixing gases. The 02 mixing ratio was varied between 0% and 50%. Film quality was evaluated using Raman spectroscopy and XPS. When 02 gas mixing ratio increased the peak in Raman spectra shifted gradually to higher wavenumbers and its bandwidth became narrower. This indicates graphite component increased in the DLC film. In addition, the lubricant coverage on oxygen-containing DLC was improved. Because adding oxygen increases the terminations of carbonyl group on DLC surface, this result suggests that the polar surface causes higher affinity for the lubricant

High resolution neutron protein crystallography. Hydrogen and hydration in proteins

Neutron diffraction provides an experimental method of directly locating hydrogen atoms in proteins, and the development of the neutron imaging plate (NIP) became a breakthrough event in neutron protein crystallography. The general features of the NIP are reviewed. A high resolution neutron diffractometer dedicated to biological macromolecules (BIX-3) with the NIP has been constructed at Japan Atomic Energy Research Institute and this has enabled 1.5 Å resolution structural analyses of several proteins to be carried out. The specifications of BIX-3 and LADI (a quasi-Laue type diffractometer installed in the Institut Laue-Langevin) are compared. The crystal structures of myoglobin, wild type rubredoxin and a mutant of rubredoxin have been carried out using BIX-3. From these studies, several topics, such as the location of hydrogen bonds and certain acidic hydrogen atoms, the identification of methyl hydrogen atoms, details of H/D exchange and dynamical behavior of hydration structures have been investigated, and important information has been extracted from the structural results. Finally, a systematic procedure to grow large single crystals of proteins or nucleic acids is described.

Fabrication and optical properties of Pb(Mg(1/3)Nb(2/3))O(3)-PbTiO(3) thin films on Si substrates using the PLD method

Epitaxial 0.67Pb(Mg(1/3)Nb(2/3))O(3)-PbTiO(3)-0.33PbTiO(3) (PMN-PT) thin films with electro-optic effects were fabricated on (PMN-PT) thin films with electro-optic effects were fabricated on (La0(0.5)Sr0(0.5))CoO(3) (LSCO)/CeO(2)/YSZ-buffered Si(001) substrates using double-pulse excitation pulsed laser deposition (PLD) method with a mask placed between the target and the substrate. Epitaxial growth of PMN-PT thin films was undertaken using the two-step growth method of PMN-PT film. The PMN-PT seed layer was deposited at 500 degrees C on the LSCO/CeO(2)/YSZ/Si, which temperature was the same as that used for LSCO deposition. The PMN-PT thin films were deposited on the PMN-PT seed layer at 600 degrees C, which enables growth of high-crystallinity PMN-PT films with smooth surfaces. We obtained optimum fabrication conditions of PMNPT film with micrometer-order thickness. Resultant films showed high crystallinity with full width at half maximum (FWHM) = 0.73 deg and 1.6 mum thickness. Electro-optic properties and the refractive index value were measured at 633 nm wavelength using the prism coupling method. The obtained refractive index was 2.59. The electro-optic coefficients r(13) and r(33) were determined by applying the electrical field between a semitransparent, thin top electrode of Pt and a bottom LSCO electrode. The electro-optic coefficient was r(13) = 17 pm/V at transverse electric field (TE) mode and r(33) = 55 pm/V at transverse magnetic field (TM) mode.