Nondestructive evaluation of blood flow in a dialyzer using X-ray computed tomography

It is very important to observe the concentrations and flow patterns of blood through a dialyzer to evaluate its function and to obtain the most appropriate design. We established a visualization method for the blood flow pattern in a dialyzer using X-ray computed tomography, and investigated the so-called internal filtration phenomenon. The results obtained were as follows: (1) The influence of 5% BaSO₄, which was added to the blood as a contrast medium, on the filtration rate of the dialyzer was minimal. (2) The relationship between the concentration of BaSO₄ and the Hounsfield unit value was expressed by linear regression. (3) Hounsfield unit values increased massively just after blood entered the dialyzer and peak values increased with dialysate perfusion under the following conditions: the dialyzer (BS-1.6UL, polysulfone hollow fibers) was used, and bovine blood with 5% BaSO₄ added was used at a blood flow rate of 200ml/min. The dialysate flow rate was 500ml/min and the slice thickness of X-ray computed tomography was 1–10mm. (4) It was observed that blood flowed slightly faster in the center than the peripheral portion of the dialyzer, when the flow pattern was followed after pulse injection of blood containing 20% BaSO₄ into the dialyzer. It was concluded that this method could possibly be utilized not only qualitatively but also quantitatively for observation of the real state of blood flow and in designing dialyzers.     

Development of analysis of drugs and toxic substances that can play an immediate role in emergency medical service: what is to be analyzed?

Our laboratory was capable of analyzing less than 20 drugs and toxic substances at the time of the establishment of the Center in 1994. Since the poisoning crimes in 1998, such as the curry poisoning with arsenic in Wakayama, the sodium azide poisoning in Niigata, and the potassium cyanide poisoning in Nagano, we have introduced methods for rapid qualitative analysis of arsenic compounds, cyanides and azides, and developed methods for qualitative analysis of three types of surfactants (cationic, anionic, and nonionic) on the basis of the statistics for intoxication patients transferred to the Center. In 1999, the Analysis Method Investigation Committee of the Japanese Society for Clinical Toxicology requested individual medical institutions to analyze 15 selected intoxicating substances, focusing on the following three aspects. 1. Intoxication with a high degree of fatality. 2. Intoxication where analysis plays an immediate role in treatment. 3. Intoxication with a high frequency of requests by clinical physicians for analysis. The selected substances included methanol, barbital drugs, benzodiazepines, tricyclic or tetracyclic antidepressants, methamphetamine, acetaminophen, salicylic acid, bromovalerylurea, organophosphorus pesticides, carbamate pesticides, paraquat, glufosinate, cyanides, arsenic, and theophylline. Responding to the Committee's request, out laboratory has been making efforts so that analysis of drugs and intoxicating substances can play an immediate role in emergency medical service, giving the highest priority to the aforementioned 15 substances. As a result, anyone of us can now rapidly analyze about 35 substances, including those listed by the Society, day and night.     

Evaluation of the test method “activated sludge, respiration inhibition test” proposed by the OECD

The test method of "activated sludge, respiration inhibition test" proposed by the OECD was critically carried out and compared with other test methods. Investigation of test conditions showed that the moderate deviation from the test conditions defined by the OECD Test Guidelines did not have much effect on the result, and some modifications were proposed to improve the method. This method had a poor detection limit compared with the LC50 test with Oryzias latipes and EC50 of the growth inhibition test with Tetrahymena pyriformis. The susceptivity of the method was particularly poor for the chemicals which were highly toxic in the other two tests.     

Acetabular osteotomy for osteoarthritis of the hip joint due to congenital dysplasia

There are several reports of the treatment for osteoarthritis due to congenital dysplasia of the hip joint. Rotational acetabular osteotomy, Chiari osteotomy and shelf operation has been introduced as the representative acetabular osteotomy. In this paper, we presented our indication of these procedures for dysplastic hip and showed indicative cases.     

Accurate and Easy Measurement of Sliding Distance of Intramedullary Nail in Trochanteric Fracture

Background

In daily clinical practice, it is essential to properly evaluate the postoperative sliding distance of various femoral head fixation devices (HFD) for trochanteric fractures. Although it is necessary to develop an accurate and reproducible method that is unaffected by inconsistent postoperative limb position on radiography, few studies have examined which method is optimal. Therefore, the purpose of this study is to prospectively compare the accuracy and reproducibility of our four original methods in the measurement of sliding distance of the HFD.

Methods

Radiographs of plastic simulated bone implanted with Japanese proximal femoral nail antirotation were taken in five limb postures: neutral, flexion, minute internal rotation, greater external rotation, and flexion with external rotation. Orthopedic surgeons performed five measurements of the sliding distance of the HFD in each of the flowing four methods: nail axis reference (NAR), modified NAR, inner edge reference, and nail tip reference. We also assessed two clinical cases by using these methods and evaluated the intraclass correlation coefficients.

Results

The measured values were consistent in the NAR method regardless of limb posture, with an even smaller error when using the modified NAR method. The standard deviation (SD) was high in the nail tip reference method and extremely low in the modified NAR method. In the two clinical cases, the SD was the lowest in the modified NAR method, similar to the results using plastic simulated bone. The intraclass correlation coefficients showed the highest value in the modified NAR method.

Conclusions

We conclude that the modified NAR method should be the most recommended based on its accuracy, reproducibility, and usefulness.     

Bloodstream infection by multidrug‐resistant Streptococcus oralis in a leukemic patient with febrile neutropenia after hematopoietic stem cell transplantation

We reported the case of a patient with leukemia who developed febrile neutropenia after hematopoietic stem cell transplantation. Blood culture results revealed the presence of Streptococcus oralis, while antimicrobial susceptibility testing showed the resistance to penicillin and cephem. Furthermore, isolates were not susceptible to either meropenem or daptomycin but not to vancomycin. S oralis is known to belong to Streptococcus mitis group and be a causative agent of bacteremia in the neutropenic patients, but multidrug resistance of S oralis is rare. Our findings suggest that we might pay attention to the emergence of the microorganisms acquiring multidrug resistance in neutropenic patients.     

Incidence of steroid-associated osteonecrosis of the talus: a prospective MRI study

Objective

The purpose of this study was to determine the incidence of steroid-associated osteonecrosis (ON) of the talus in systemic lupus erythematosus (SLE) patients using a prospective magnetic resonance imaging (MRI) study.

Methods

We prospectively evaluated 110 SLE patients (220 tali) who required corticosteroid therapy using MRI. The incidence of ON of the talus was compared with the incidence of ON of the femoral head. We also divided these patients into two groups: those with and without ON of the talus. We compared these groups for gender differences, ages at initial corticosteroid therapy, and highest daily corticosteroid dosages.

Results

The incidence of ON of the talus was significantly lower than the incidence of ON of the femoral head (7.3 versus 49.5 %; p?<?0.001). No significant differences for gender, age at initial corticosteroid therapy, or highest daily corticosteroid dosage were observed between patients with and without ON of the talus. The rate of ON of the bilateral femoral head was significantly higher in those with ON of the talus than in those without ON of the talus.

Conclusion

Our results revealed that the incidence of ON of the talus was significantly lower than the incidence of ON of the femoral head.     

Use of non‐enhanced angiography to assist the second toetip flap transfer for reconstruction of the fingertip defect

Toetip flap transfer is a useful reconstructive method for fingertip defect, but elevation of a toetip flap is technically demanding because of difficulty to dissect a pedicle vein of the flap. Recently, nonenhanced angiography (NEA) has been reported to be useful for preoperative visualization of the digital vessels without contrast enhancement or invasiveness. We report a case in which preoperative NEA visualized a vein suitable for a venous pedicle of a second toetip flap and facilitated successful toetip flap transfer for reconstruction of a fingertip defect. A 27‐year‐old male suffered from the right middle fingertip crush amputation in Tamai zone 1. The fingertip was reconstructed using a second toetip flap with preoperative NEA guidance. A pedicle vein was easily found and dissected exactly where NEA visualized. Nine months after the toetip flap transfer, the reconstructed right middle finger was functionally and aesthetically pleasing, and the toe nail at the donor site was preserved without any morbidity. NEA may help a surgeon to find drainage veins for a toetip flap, which leads to easier and more secure toetip flap transfer. © 2014 Wiley Periodicals, Inc. Microsurgery 34:481–483, 2014.     

Separate mechanisms for development and performance of compulsive checking in the quinpirole sensitization rat model of obsessive-compulsive disorder (OCD)

Rationale

Acute administration of serotonergic agonist, meta-chlorophenylpiperazine (mCPP), attenuates performance of compulsive checking in an animal model of obsessive-compulsive disorder (OCD). It is not known whether mCPP has a similar effect on development of compulsive checking.

Objectives

The objective of the study was to examine whether similar mechanisms mediate the development versus the performance of compulsive checking in the rat model.

Methods

Four groups of male rats (N?=?14/group) were tested: two experimental groups co-injected with D2/D3 dopamine agonist quinpirole (0.25 mg/kg) and mCPP (0.625 mg/kg or 1.25 mg/kg), and two control groups, one co-injected with quinpirole and saline, the other receiving injections of saline. The time course of development of compulsive checking across injections 1 to 10 in quinpirole-treated rats was compared to rats co-injected with quinpirole and mCPP.

Results

Results showed that during the course of chronic treatment, mCPP (1.25 mg/kg) significantly attenuated performance of checking behavior. However, when these rats were retested for expression of compulsive checking (that is, with an injection of quinpirole only), their profile of compulsive checking was no different from the control rats treated throughout with quinpirole only.

Conclusions

Findings show that mCPP inhibits performance of compulsive checking but does not block quinpirole from inducing the neural substrate underlying this compulsive behavior. Hence, a separate mechanism underlies the induction of compulsive checking and the performance of it. It is suggested that development of the OCD endophenotype reflects neuroplastic changes produced by repeated dopamine D2/D3 receptor stimulation, while stimulation of serotonergic receptors mediates a negative feedback signal that shuts down the motor performance of checking.     

Establishment of a T-Cell Line from Lymphocytes Presumably Implicated in Posttransfusion Graft-versus-Host Disease

Posttransfusion graft-versus-host disease (PTGVHD) is known to develop in immunocompetent patients exhibiting clinical symptoms such as erythroderma, fever, liver dysfunction, diarrhea and pancytopenia. It is speculated that transfused blood donors' lymphocytes might recognize the recipients' HLAs as alloantigens. The thus stimulated lymphocytes might proliferate, expand and finally attack the host's immune system or tissues. However, details regarding these expanded donor cells such as: (1) whether they represent one clone or more, (2) the composition of lymphocyte subsets, and (3) the target HLA antigens of recipients, are not clear, since T-cell lines derived from PTGVHD patients have not yet been obtained. The aim of this study is to characterize T-cells responsible for PTGVHD and to identify their target molecules. For that purpose, we attempted to establish T-cell lines derived from a PTGVHD patient. We show that the established T-cell line, proven to be derived from donor lymphocytes, showed a CD4+ phenotype and had cytotoxic activities. Furthermore, we describe that the target of the cytotoxic T-cell line (CTL) is an HLA-DRBl*0405-related molecule of the patient.