Catalytic and Aerobic Oxidative Biaryl Coupling of Anilines Using a Recyclable Heterogeneous Catalyst for Synthesis of Benzidines and Bicarbazoles

In this study, a heterogeneous rhodium-catalyzed oxidative homocoupling reaction of anilines utilizing molecular oxygen as the sole oxidant is reported. Employing a commercially available and recyclable Rh/C catalyst enabled the oxidative dimerization of various anilines, including N,N-disubstituted and N-monosubstituted anilines, as well as diarylamines, triarylamines, and carbazoles. Additionally, the catalytic protocol was extended to the ortho-ortho coupling of anilines, affording 2,2'-diaminobiphenyls with high regioselectivity. Notably, the developed approach provides rapid access to diversely functionalized benzidines and diaminobiphenyls in an operationally simple, practical, and environmentally friendly manner.

Early results of a randomized two-by-two factorial phase II trial comparing neoadjuvant chemotherapy with two and four courses of cisplatin/S-1 and docetaxel/cisplatin/S-1 as neoadjuvant chemotherapy for locally advanced gastric cancer

Background

Neoadjuvant chemotherapy (NAC) is a promising method of improving the survival of resectable gastric cancer. Cisplatin/S-1 (CS) and docetaxel/cisplatin/S-1 (DCS) are both effective against metastatic gastric cancer. This report clarified the impact of these regimens on early endpoints, including the pathological responses, chemotherapy-related toxicities, and surgical results.

Methods

Patients with M0 and either T4 or T3 in case of junctional cancer or scirrhous type received two or four courses of cisplatin (60 mg/m2 at day 8)/S-1 (80 mg/m2 for 21 days with 1 week rest) or docetaxel (40 mg/m2 at day 1)/cisplatin (60 mg/m2 at day 1)/S-1 (80 mg/m2 for 14 days with 2 weeks rest) as NAC. Patients then underwent D2 gastrectomy and adjuvant S-1 chemotherapy for 1 year. The primary endpoint was the 3-year overall survival.

Results

Between October 2011 and September 2014, 132 patients were assigned to receive CS (n = 66; 33 in 2 courses and 33 in 4 courses) or DCS (n = 66; 33 in 2 courses and 33 in 4 courses). The respective major grade 3 or 4 hematological toxicities (CS/DCS) were leukocytopenia (14.1%/26.2%), neutropenia (29.7%/47.7%), anemia (14.1%/12.3%), and platelet reduction (3.1%/1.5%). The rate of pathological response, defined as a complete response or < 10% residual cancer remaining, was 19.4% in the CS group and 15.4% in the DCS group, and 15.6% in the two-course group and 19.0% in the 4-course group. The R0 resection rate was 72.7% in the CS group and 81.8% in the DCS group and 80.3% in the two-course group and the 74.2% in the four-course group. No treatment-related deaths were observed.

Conclusions

Our results do not support three-drug therapy with a taxane over two-drug therapy, or any further treatment beyond two cycles as an attractive candidate for the test arm of NAC.

Clinical characteristics and outcomes of adenovirus infection of the urinary tract after renal transplantation

BACKGROUND

Urinary tract infection caused by human adenovirus (HAdV) after renal transplantation (RT) results in graft loss because of concomitant nephropathy and acute rejection and may result in death because of systemic dissemination.

METHODS

We assessed the time period between RT and disease onset, symptoms, treatment details, disease duration, renal graft function, outcomes, and complications.

RESULTS

HAdV infection of the urinary tract occurred in 8 of 170 renal transplant recipients. Symptoms were macrohematuria in all 8 patients, dysuria in 7, and fever in 5. The median period from RT to disease onset was 367 (range, 7-1763) days, and the median disease duration was 15 (range, 8-42) days. The mean serum creatinine (sCr) level prior to onset was 1.35 ± 0.48 mg/dL and the mean maximum sCr level during disease was 2.34 ± 1.95 mg/dL. These values were increased by ≥25% in 5 patients. The mean sCr levels when symptoms resolved was 1.54 ± 0.67 mg/dL, and no significant difference was seen before, during, or after disease onset (P = 0.069). Two patients were diagnosed with HAdV viremia and 1 with acute tubulointerstitial nephritis revealed on biopsy. In addition to a reduction in immunosuppressant dosage, 2 patients received gammaglobulins and 5 received ganciclovir.

CONCLUSION

Symptoms of all patients were alleviated, although some patients developed nephritis or viremia. Hence, the possibility of exacerbation should always be considered. Adequate follow-up observation should be conducted, and diligent and aggressive therapeutic intervention is required to prevent the condition from worsening.

Effect of heat stress soon after muscle injury on the expression of MyoD and myogenin during regeneration process

Heat stress could promote skeletal muscle regeneration. But, in the regeneration process, effects of heat stress on myogenic cells and the regulating factors is unknown. Therefore, Influences of heat stress soon after injury on distribution of the myogenic cells and chronological changes in expression of MyoD and myogenin were examined. The first peak of MyoD expression was temporally correlated with the time when proliferating satellite cells began to appear, and the rapid decline of the MyoD expression from the first peak, with the appearance time of myoblasts, respectively in both the non-Heat and Heat groups. The first peak of myogenin expression was temporally correlated with the time when multinuclear cells began to form in the both groups. Due to the heat stress, proliferation and differentiation of myogenic cells and chronological changes in these factors were accelerated one day earlier than in the non-Heat group. As MyoD and myogenin are regulating factor of proliferation and differentiation, heat stress soon after the muscle injury could accelerate the proliferation and differentiation of myogenic cells and the expression of their regulating factors MyoD and myogenin.

PP111. The preceding features before onset of gestational hypertension and preeclampsia in home blood pressure monitoring: The existence of the inflection point and the rapid increased speed of blood pressure

INTRODUCTION

It has not been clarified whether home blood pressure monitoring (HBPM) during pregnancy is useful to detect high risk pregnant women with later onset of gestational hypertension (GH) and preeclampsia (PE).

OBJECTIVES

We thought to determine the preceding features of blood pressure (BP) in HBPM before the onset of GH and PE. We especially focused on the existence of the inflection point, its level, when it occurs, and the increased speed of BP after the inflection point. We compared these features in normal pregnant women (NP), women with GH, and women with PE.

METHODS

In this prospective cohort study, 361 singleton pregnant women, among them 100 women recruited due to high risk for GH/PH in the second trimester, participated in a couple of tertiary perinatal centers between 2008 and 2010. HBPM were measured with the validated OMRON HEM-5001(R) automated digital oscillometric sphygmomanometer (OMRON Healthcare Japan). The device was programmed to take three consecutive readings at 15-second interval. HBPM was measured twice a day, at the time of awakening and sleep, through the first to third trimester, and the average systolic blood pressure (SBP) and diastolic blood pressure (DBP) of each gestational week (almost 42 times a week) were calculated. We defined the data of HBPM which started before 28 gestational weeks and continued until 2 weeks before the onset of GH/PE or delivery are eligible. The increased speed of systolic or diastolic BP after the inflection point was defined as ("BP at the onset in GH/PE or at delivery in NP" - "BP at the inflection point") / ("Gestational weeks at the onset in GH/PE or at delivery in NP" - "Gestational weeks at the inflection point"). If there was no inflection point in HBPM, the increased speed of BP was defined as zero. The comparisons were performed using one-way analysis of variance (ANOVA) followed by multiple comparison. Data were shown as mean±SE.

RESULTS

A total of 17 (4.7%) women developed PE, and 12 (3.3%) GH.The systolic blood pressure (SBP) levels at the inflection point in NP, GH and PE was 102.4±1.3, 118.7±2.9 and 117.4±2.2mmHg, respectively (Significant pairs: NP < GH, PE); the diastolic blood pressure (DBP) levels at the inflection point was 59.2±1.0, 74.5±2.0 and 73.1±2.0mmHg, respectively (NP < GH, PE). The inflection point in NP, GH and PE occurred at 31.3±0.9, 28.4±1.5 and 22.3±1.4weeks, respectively (PE < GH, NP). The increased speed of SBP in NP, GH and PE was 1.2±0.1, 3.0±0.4 and 4.7±0.7mmHg/wk, respectively (NP < GH, PE); the increased speed of DBP was1.1±0.1, 2.1±0.3 and 2.8±0.4mmHg/wk, respectively (NP < GH, PE).

CONCLUSION

In women with later onset of GH/PE, the BP level at the inflection points was higher than in NP. The average inflection point in PE was earlier gestational weeks than in GH and NP. The average increased speed of blood pressure after the inflection point in GH/PE was faster than in NP. The preceding features of BP in HBPM may be clinically useful to detect high risk women with later onset of GH/PE.

Learning curve of laparoscopy-assisted gastrectomy using a standardized surgical technique and an established educational system

BACKGROUND AND AIMS

The learning curve of a trainee for laparoscopy-assisted gastrectomy in a high volume center, in which an educational system and a standardized laparoscopic procedure are already established, remains unclear.

MATERIAL AND METHODS

The early surgical outcomes of the patients of two trainees were investigated. Both trainees followed a training program where they performed at least 20 cases being the camera assistant, 20 cases being the first assistant, before performing the surgery as an operator.

RESULTS

The average operation time, intraoperative bleeding, the number of retrieved lymph nodes, and morbidity rate were 240.2 min, 45.7 ml, 35.4, and 13.0%, respectively. There was no learning curve effect observed except with the operation time of one trainee.

CONCLUSIONS

In a high volume center with an established educational system, trainees could perform laparoscopy-assisted gastrectomy safely, although there might be a -learning curve effect in operation time and the surgeries took longer operation time in trainee's initial cases.

Evaluation of viable β-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 β-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 β-cell viability (54.3 ± 3.4% vs. 72.0 ± 2.1%, p < 0.01), β-cell mass (93,671 ± 11,150 vs. 148,961 ± 12,812 IEQ, p < 0.01), and viable β-cell mass (47,317 ± 6,486 vs. 106,631 ± 10,228 VβIEQ, 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 β-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 β-cell mass contained in human islet preparations will be useful for selecting enzyme blends.

Digital Chemical Vapor Deposition of Silicon Oxide/Nitride and its Surface Reaction Study

In order to fill high quality insulators into narrower spaces in advanced metallizationthe digital CVD (Chemical Vapor Deposition) of multilayer stacked Si oxide and nitride films was studied. Reaction of TES (triethylsilane) with hydrogen (H) atoms was also found to lead to conformal CVD of Si film involving organic species. This reaction took place only on the surface reaction. In-situ FTIR studies reveal that H atoms react with Si-C2H5 bonds in TES and thus generate strong Si-CH3 bonds and weak Si-H bonds, thereby liberating H2 and forming the organic Si film on the surface, and the surface reaction is dominated by the thermal effect from the substrate. Then Si oxide or nitride films were formed by the digitaCVD which repeated a cycle of deposition of this film with subsequent oxidation or nitridation. Oxide film integrity was improved greatly by removing included organic bonds in the TES/H reaction film by exposing the film to H atoms before the oxidation step. Thus electrically excellent multilayer stacked oxide and nitride films were obtained in a deep trench.

Warfarin and miconazole oral gel interactions: analysis and therapy recommendations based on clinical data and a pharmacokinetic model

WHAT IS KNOWN AND OBJECTIVE

Miconazole is a strong inhibitor of CYP2C9, one of the main enzymes involved in the metabolism of warfarin. Concurrent use of the two drugs leads to potentially serious adverse effects. Although it is often assumed that use of the oral miconazole gel is acceptable with concomitant warfarin, because of the low bioavailability following buccal administration, drug-drug interactions have been reported following such use. We aimed to investigate case reports of such interactions and develop a pharmacokinetic model to model such interactions.

METHODS

The Medline database from 1966 to October 2010 was used for literature search. Case reports of the potentiation of the anticoagulant effects of warfarin, such as the elevation of prothrombin time (INR), by concomitant administration of warfarin and miconazole oral gel were collected. We quantitatively estimated the extent of inhibition of warfarin metabolism by orally administered miconazole gel and compared our findings with case reports.

RESULTS AND DISCUSSION

Metabolism of (S)-warfarin is inhibited potently following administration of a standard dose (200-400 mg/day in Japan) of miconazole gel. This may lead to in an increase in the blood concentration of warfarin and lead to serious adverse effects. The literature reports of clinical interactions with concomitant use of those drugs show that other factors may amplify the effects of any increase in blood concentration.

WHAT IS NEW AND CONCLUSION

We summarize all reported, clinically significant, cases of drug interaction between miconazole oral gel and warfarin. Pharmacokinetic modelling shows that concomitant administration of warfarin and miconazole oral gel can lead to substantial increase in warfarin concentration. However, our PK/PD model fails to capture the dramatic increases seen in INR values, and hence bleeding complications, reported in the literature. Taken together, the evidence suggests that concomitant use of miconazole gel and warfarin should be avoided. Even over-the-counter products containing miconazole should be used with caution by patients receiving warfarin.

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 β-cell viability were comparable, β-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-1β, TNF-α, IFN-γ, IL-6, IL-8, MIP-1β, 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 β-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.

Toward improving human islet isolation from younger donors: rescue purification is efficient for trapped islets

Several reports suggest that islets isolated from younger donor pancreata are of better quality for clinical islet transplantation. The relative inefficiency of the continuous gradient purification process (CGP) is one of the major obstacles to the utilization of these younger donor pancreata. This study demonstrates the benefits of utilizing an additional purification step, rescue gradient purification (RGP), to recover trapped islets and examines the possible superiority of these rescued islets. Seventy-three human islet isolations purified by RGP following CGP were divided into two groups based on age, and the isolation results were retrospectively analyzed (group I: age < or = 40, group II: age > 40). The quality of islets from both CGP and RGP were assessed by beta-cell fractional viability (beta FV) and ADP/ATP ratio. Significant increases in the percent islet recovery from RGP and the percent trapped islets in group I compared to group II were observed. Donor age correlated negatively to the percent islets recovered from RGP (R = 0.440) and to the percent of trapped islets (R = 0.511). RGP islets had higher beta FV and better ADP/ATP ratio compared to CGP islets. In conclusion, RGP improved the efficiency in the purification of trapped islets, which often come from younger donor pancreata. The better quality of beta-cells in RGP islets encourages us to perform RGP, considering the higher quality as well as the quantity of remaining islets.

Effect of pituitary adenylate cyclase-activating polypeptide in islet transplantation

INTRODUCTION

Pituitary adenylate cyclase-activating polypeptide (PACAP) is an islet substance serving as an intra-islet amplifier of glucose-induced insulin secretion similar to exendin-4. It has been reported that systemic administration of PACAP maintained beta-cell mass, delayed the onset of hyperglycemia, and protected beta cells from glucose toxicity. Moreover, PACAP increases glucose-stimulated insulin release in vitro and in vivo. In this study, we investigated the possibility of PACAP use in human islet transplantation.

METHODS

Human islets were cultured in the presence or absence of PACAP (10(-12) mol/L) for 48 hours. We assessed beta-cell viability using FACS, cellular composition analysis by iCys/LSC, and glucose-stimulated insulin secretion. In vivo, islets were transplanted beneath the kidney capsule of Streptozotocin-induced diabetic immunodeficient mice. An intravenous glucose tolerance test (IVGTT) was also performed in the presence or absence of PACAP (Peptide International, Louisville, Ky, United States; 1.3 nmol/kg).

RESULTS

There were significant improvements in terms of beta-cell viability and cellular composition between islets cultured with or without PACAP, respectively (P < .05). Moreover, glucose-stimulated insulin secretion significantly improved in islets cultured with PACAP compared with controls, respectively (P < .05). Treatment of recipient mice with PACAP resulted in beneficial effects on insulin secretion (PACAP vs control, 13.2 vs 1.9 mU/L), in IVGTT. However, no significant difference was observed in glucose levels between the 2 groups.

CONCLUSIONS

Our study indicated that PACAP significantly improved beta-cell viability and survival during culture, and increased insulin secretion in vitro and in vivo. However, blood glucose levels in vivo after an IVGTT did not significantly improve, probably due to increased glucagon secretion from alpha cells. PACAP supplementation to culture medium could be of assistance to improve clinical islet transplantation outcomes.

Purification method using iodixanol (OptiPrep)-based density gradient significantly reduces cytokine chemokine production from human islet preparations, leading to prolonged beta-cell survival during pretransplantation culture

Purification is one of the most important steps in human islet isolation. Although Ficoll-based density gradients are widely used, OptiPrep-based density gradients are used in few centers. Cytokine/chemokine production from human islet preparations varies widely. Some cytokines/chemokines have been reported to have adverse effects on human islet preparations. Control of cytokine/chemokine production may be a key to improve islet quality and quantity, leading to better transplantation outcomes. The aim of the present study was to investigate the effects on islet preparations of purification methods using various density gradients on viability, cellular composition, and proinflammatory cytokine/chemokine production. After the digestion phase, the extracts were divided into 2 groups for purification using a semiautomated cell processor with Ficoll-based or OptiPrep-based density gradients. Islet preparations cultured for 2 days were assessed regarding islet cell viability (fluorescein diacetate/propidium iodide [FDA/PI]), fractional beta-cell viability by FACS, and beta-cell content using iCys. Cytokine/chemokine production from islet preparations was also measured by Bio-plex. After purification, the purity, islet equivalents (IEQ), and islet recovery rates were comparable between the 2 groups. Although FDA/PI and fractional beta-cell viability showed no significant difference, survival of beta cells during culture was significantly higher in the OptiPrep compared with the Ficoll-based density gradient group. There were significantly lower tumor necrosis factor (TNF)-alpha, interleukin (IL)-1beta, interferon (IFN)-gamma, IL-6, and MIP-1beta productions from the OptiPrep-based density gradient group. OptiPrep-based density gradients reduced cytokine/chemokine production by islet preparations. In addition, OptiPrep-based density gradient purification significantly reduced the loss of beta-cell mass during pretransplantation culture.

In situ quantitative immunoprofiling of regulatory T cells using laser scanning cytometry

Laser scanning cytometry (iCys; CompuCyte, Cambridge, Mass) has recently been developed to use fluorescence-based quantitative measurements on tissue sections or other cellular preparations at a single-cell level. The purpose of this study was to develop objective, quantitative immunoprofiling of regulatory T cells (T regs) on formalin-fixed/paraffin-embedded (FFPE) biopsy samples from transplanted allografts using iCys. We sought to evaluate the usefulness of iCys to analyzes the population of CD4 (+) Foxp3 (+) T regs among CD4 (+) T-cell and the entire T-cell (the total of CD4 [+] and CD8 [+] populations in human intestinal allograft biopsy samples. Primary antibodies (Foxp3 and CD4) which had been labeled using Alexa Fluoro 488 (Foxp3 Alexa488) and 647 (CD4 Alexa647) with polymer horseradish peroxidase and catalyzed signal amplification were incubated on 1 section. On the other section, CD8 and CD4 were labeled using Alexa488 and Alexa647 using the same protocol. Data acquisition was performed using iCys. The signal intensities of Alexa488 and Alexa647 were sufficient to analyze by iCys. Distribution of the integrals of Alexa488 and Alexa647 to visualize each cell population enabled calculation of the population of T reg among CD4 (+) T cells, CD4 (+) T cells among total T cells, and T reg among entire T cells. iCys and signal amplified immunofluorescent staining allowed objective quantitative immunoprofiling of in situ T reg populations, with precise quantitative analysis at a single-cell level on FFPE sections. This objective method may be applied on biopsy samples from various transplanted organs.

Isolation, identification and excretion profile of the principal urinary metabolite of the recently banned designer drug 1-(3-trifluoromethylphenyl)piperazine (TFMPP) in rats

The metabolism of 1-(3-trifluoromethylphenyl)piperazine (TFMPP), a recently banned designer drug, in rats was studied by analysing its urinary metabolites. p-Hydroxy-TFMPP (p-OH-TFMPP) was isolated and identified as the main metabolite by using nuclear magnetic resonance spectroscopy, gas chromatography-mass spectrometry and high-performance liquid chromatography-electrospray ionization mass spectrometry (LC-ESI MS). The time-course excretion profiles of TFMPP and p-OH-TFMPP in rats were investigated following a single intraperitoneal dosing of 5 mg kg(-1) TFMPP by using an optimized analytical procedure that combined solid-phase extraction and LC-ESI MS techniques. The cumulative amount of p-OH-TFMPP excreted within the first 48 h reached approximately 64% of the dose, of which 70% was the glucuronide conjugated form. The cumulative amount of parent TFMPP excreted was less than 0.7% of the dose. The results suggest that p-OH-TFMPP would be the most relevant metabolite to be detected for TFMPP exposure in the forensic and clinical analysis of human urine.

Effect of human islet rescue gradient purification on islet yield and fractional Beta cell viability

It is difficult to consistently obtain sufficient postpurification islet numbers from younger donors because of the higher proportion of trapped islets after pancreas digestion. Continuous gradient purification (CGP), which is currently used in several islet processing centers, sometimes is not efficient in the purification of trapped islets. Rescue gradient purification (RGP) could improve postpurification islet yields, resulting in an increased number of islet cell products that could be transplanted. Sixty-eight human islet isolations, in which CGP was followed by RGP were analyzed. The quality of islets from CGP and RGP was assessed by beta-cell fractional viability (betaFV) and ADP/ATP ratio. Donor age negatively correlated with the proportion of the islets rescued by RGP (R = -0.52; P < .01) and to the percentage of trapped islets (R = -0.46; P < .01). Age-related differences were observed in pancreas weight, digestion time, and islet yields from CGP, respectively. Importantly, islets from RGP had an 11% higher betaFV compared with islets from CGP. ADP/ATP ratio was also lower in RGP islets versus CGP islets. RGP improved the efficiency of islet purification from younger pancreata and did not affect islet cell viability, which was actually higher in RGP fractions, indicating that rescued trapped islets from the pellet and lower purity layers are not damaged by the extra purification step and may actually be more viable. RGP could be used to rescue high-quality islets from less than 30% pure islet fractions, which are often discarded in the clinical setting.

Factors that affect human islet isolation

More than 10,000 IEQ/kg recipient weight of islets is often necessary to achieve insulin independence in patients with type 1 diabetes mellitus. Several studies have identified high donor body mass index (BMI) and pancreas size as important factors for the success of human islet isolation. However, the donor shortage underscores the need to improve isolation outcomes from lower BMI pancreas donors and/or small pancreata. The aim of this study was to identify the critical factors that affect isolation outcome. We analyzed the data from 207 isolations performed from 2002 to 2006 with respect to donor characteristics, pancreas condition, and processing variables. More than 3000 IEQ/g pancreas weight was considered to be an acceptable isolation outcome. This goal was obtained from donors with a BMI >30 kg/m2 (P = .002). The pancreatic surface integrity was also a significant factor (P = .02). Moreover, longer digestion times (P = .04) and a greater proportion of trapped islets negatively affected success rates (P = .004). As previously reported, pancreata from high BMI donors were suitable for islet isolation and transplantation, as they yielded higher total islet particle numbers and higher IEQ/g. Although BMI and pancreas size are not controllable due to the organ donor shortage, factors such as pancreatic surface integrity, shorter digestion time, and lower proportions of trapped islets were found to be significant to obtain higher success rates. The development of better protocols and systematic training of processing/procurement teams will be of assistance to increase the number of successful human islet isolations.

Laparoscopic and endoscopic cooperative surgery for gastrointestinal stromal tumor dissection

BACKGROUND

Laparoscopic wedge resections are increasingly applied for gastric submucosal tumors such as gastrointestinal stromal tumor (GIST). Despite this, no defined strategy exists to guide the surgeon in choosing the appropriate laparoscopic technique for an individual case on the basis of tumor characteristics such as location or size. This study aimed to introduce a laparoscopic and endoscopic cooperative surgery (LECS) for gastric wedge resection that is applicable for submucosal tumor resection independent of tumor location and size.

METHODS

Seven patients underwent LECS for the resection of gastric submucosal tumors. Both mucosal and submucosal layers around the tumor were circumferentially dissected using endoscopic submucosal dissection via intraluminal endoscopy. Subsequently, the seromusclar layer was laparoscopically dissected on the exact three-fourths cut line around the tumor. The submucosal tumor then was exteriorized to the abdominal cavity and dissected with a standard endoscopic stapling device.

RESULTS

In all cases, the LECS procedure was successful for dissecting out the gastric submucosal tumor. In four of seven cases, the tumor was located in the upper gastric portion near the esophagogastric junction. The remaining three tumors were in the posterior gastric wall. In two cases, the tumors were more than 5 cm in diameter, and one was a GIST of the remnant stomach. The mean operation time was 169 +/- 17 min, and the estimated blood loss was 7 +/- 2 ml. The postoperative course was uneventful in all cases.

CONCLUSIONS

The LECS procedure for dissection of gastric submucosal tumors such as GIST may be performed safely with reasonable operation times, less bleeding, and adequate cut lines. In addition, the success of the procedure does not depend on the tumor location such as the vicinity of the esophagogastric junction or pyloric ring.

Cooperative roles of Par-3 and afadin in the formation of adherens and tight junctions

Par-3 is a cell-polarity protein that regulates the formation of tight junctions (TJs) in epithelial cells, where claudin is a major cell-cell adhesion molecule (CAM). TJs are formed at the apical side of adherens junctions (AJs), where E-cadherin and nectin are major CAMs. We have revealed that nectin first forms cell-cell adhesions, and then recruits cadherin to nectin-based cell-cell adhesion sites to form AJs and subsequently recruits claudin to the apical side of AJs to form TJs. The cytoplasmic tail of nectin binds afadin and Par-3. Afadin regulates the formation of AJs and TJs cooperatively with nectin. Here, we studied the role of Par-3 in the formation of these junctions by using Par-3-knockdown MDCK cells. Par-3 was necessary for the formation of AJs and TJs but was not necessary for nectin-based cell-cell adhesion. Par-3 promoted the association of afadin with nectin, whereas afadin was not necessary for the association of Par-3 with nectin. However, the association of afadin with nectin alone was not sufficient for the formation of AJs or TJs, and Par-3 and afadin cooperatively regulated it. We describe here these novel roles of Par-3 in the formation of junctional complexes.

Possible case of potentiation of the antiplatelet effect of cilostazol by grapefruit juice

We present a case of purpura associated with concomitant ingestion of cilostazol, aspirin and grapefruit juice. A 79-year-old man with atherosclerosis obliterans, taking cilostazol and aspirin, complained of purpura. Interview by a pharmacist revealed that he had been taking grapefruit juice for a month. His purpura disappeared upon cessation of grapefruit juice, although his medication was not altered. The most probable cause of his purpura is an increase in the blood level of cilostazol because of the inhibition of cilostazol metabolism by components of grapefruit juice. Aspirin may possibly have potentiated the risk of purpura. Grapefruit juice should be avoided in patients taking cilostazol, especially in patients being concomitantly treated with other anticoagulants.

Establishment of a sequence-based typing system for BoLA-DQA1 exon 2

In cattle, bovine leukocyte antigens (BoLAs) have been extensively used as markers for bovine diseases and immunological traits. Here, we developed a rapid, high-resolution sequence-based typing (SBT) system for BoLA-DQA1. We amplified 355 bp of BoLA-DQA1 by fully nested polymerase chain reaction (PCR) using the newly constructed primers and then performed direct sequencing of each product. Using this method, we investigated the locus in 51 animals whose BoLA haplotypes had been characterized at the Fifth International BoLA Workshop. We identified 15 distinct DQA1 alleles, and there is no conflict between the typing result of PCR-SBT and restriction fragment length polymorphism analysis. Together with the previously developed method for typing BoLA-DRB3, the PCR-SBT for BoLA-DQA1 clearly provides a useful tool for detailed class IIa haplotype analysis.

Metabolism of the recently encountered designer drug, methylone, in humans and rats

The urinary metabolites of methylone in humans and rats were investigated by analysing urine specimens from its abuser and after administrating to rats with gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-electrospray ionization mass spectrometry (LC-ESI MS), using authentic standards. The time-course excretion profiles of methylone and its three metabolites in rats were further investigated after a single intraperitoneal dosing of 5 mg kg-1 methylone hydrochloride. Two major metabolic pathways were revealed for both humans and rats as follows: (1) side-chain degradation by N-demethylation to the corresponding primary amine methylenedioxycathinone (MDC), partly conjugated; and (2) demethylenation followed by O-methylation of either a 3- or 4-OH group on the benzene ring to produce 4-hydroxy-3-methoxymethcathinone (HMMC) or 3-hydroxy-4-methoxymethcathinone (3-OH-4-MeO-MC), respectively, mostly conjugated. Of these metabolites, HMMC was the most abundant in humans and rats. The cumulative amount of urinary HMMC excreted within the first 48 h in rats was approximately 26% of the dose, and the amount of the parent methylone was not more than 3%. These results demonstrate that the analysis of HMMC will be indispensable for proof of the use of methylone in forensic urinalysis.

Dosage adjustment of quinolone antibiotics and angiotensin-converting enzyme inhibitors in patients with renal dysfunction

The aim of this study was to verify an approach for calculating pharmacokinetic parameters suitable for adjusting dosage regimens in patients with renal dysfunction. We carried out a retrospective analysis of the pharmacokinetic profiles of 12 new quinolone antibiotics and 11 angiotensin-converting enzyme inhibitors (ACEIs) in patients with normal and impaired renal function to obtain the renal excretion ratio (R(renal)) of each drug. We demonstrated that the pharmacokinetics of each drug in a patient with renal dysfunction can be adequately estimated using the R(renaI) value of each drug together with the creatinine clearance as an index of the individual's renal function. Using the R(renaI) value obtained, we could successfully simulate pharmacokinetic profiles of the drugs in publications other than that used to obtain the R(renal) values. On the other hand, age-related changes in the pharmacokinetics of new quinolone antibiotics are not always adequately predicted using the R(renal) value compared to using creatinine clearance alone as an index, and the reasons for this are not fully understood. These results demonstrate that dosage regimens of quinolone antibiotics and ACEIs in patients with renal dysfunction can be adequately optimized using the R(renal) value for each drug using the present approach.

Magnocellular and parvocellular visual pathways have different blood oxygen level-dependent signal time courses in human primary visual cortex

PURPOSE

The magnocellular and parvocellular pathways (M and P pathways) are the major pathways of the visual system, with distinct histologic and physiologic properties that may also have different metabolic characteristics. We hypothesize that the differences of the 2 visual pathways would also manifest as differences in the signal time course of blood oxygen level-dependent functional MR imaging (BOLD fMRI). The differences in BOLD signal time course may provide insight into the metabolic requirements of the 2 pathways.

METHODS

Eleven fMRI sessions on 6 subjects were performed using stimuli that preferentially activated the 2 pathways. Regions commonly activated by both the M and P stimuli in the primary visual cortex (V1) were determined, and the contrast elicited by the stimulus, time-to-peak (TTP), and the full width at half maximum (FWHM) of the BOLD signal time course were measured.

RESULTS

The functional stimuli activated cortical regions described previously in the literature, such as V1, V4, and V5. Within V1, the TTP of the signal time course of the 2 stimuli were statistically different, with the P stimulus generating TTPs that were on average 12% faster than the M stimulus (P = .0037).

CONCLUSION

We have demonstrated the ability to functionally differentiate the M and P stimuli in a commonly activated anatomic region. Because the BOLD response is dependent on the ratio of oxyhemoglobin and deoxyhemoglobin in the blood, the difference in the BOLD time course between the 2 stimuli suggests that the oxygen demand of the 2 pathways may be different.

Gastrointestinal Candida colonisation promotes sensitisation against food antigens by affecting the mucosal barrier in mice

BACKGROUNDS AND AIMS

Controversy still exists as to whether gastrointestinal colonisation by Candida albicans contributes to aggravation of atopic dermatitis. We hypothesised that Candida colonisation promotes food allergy, which is known to contribute to a pathogenic response in atopic dermatitis. We tested this using a recently established murine Candida colonisation model.

METHODS

Candida colonisation in the gastrointestinal tract was established by intragastric inoculation with C albicans in mice fed a synthetic diet. To investigate sensitisation against food antigen, mice were intragastrically administered with ovalbumin every other day for nine weeks, and antiovalbumin antibody titres were measured weekly. To examine gastrointestinal permeation of food antigen, plasma concentrations of ovalbumin were measured following intragastric administration of ovalbumin.

RESULTS

Ovalbumin specific IgG and IgE titres were higher in BALB/c mice with Candida colonisation than in normal mice. Gastrointestinal permeation of ovalbumin was enhanced by colonisation in BALB/c mice. Histological examination showed that colonisation promoted infiltration and degranulation of mast cells. Candida colonisation did not enhance ovalbumin permeation in mast cell deficient W/Wv mice but did in congenic littermate control +/+ mice. Reconstitution of mast cells in W/Wv mice by transplantation of bone marrow derived mast cells restored the ability to increase ovalbumin permeation in response to Candida colonisation.

CONCLUSIONS

These results suggest that gastrointestinal Candida colonisation promotes sensitisation against food antigens, at least partly due to mast cell mediated hyperpermeability in the gastrointestinal mucosa of mice.

Comparison of the collecting efficiency of microbiological air samplers

It is important to evaluate the prevention of nosocomial infections caused by airborne micro-organisms in healthcare facilities. For that purpose, the use of an air sampler is required. A comparison of the collecting efficiency of air samplers has not been studied so far using a single culture medium. Use of the same culture medium is necessary because of the variation of the cultivation efficiency with different culture media. In this study a statistically significant difference in collecting efficiency among air samplers was observed in case of SCDA (soybean casein digest agar) culture medium, but not SCDALP (soybean casein digest agar lecithin polysorbate) culture medium. In addition, a statistically significant difference of the cultivation efficiency was observed between SCDA and SCDALP culture media (P<0.05). These results suggest that any air sampler can be used with SCDALP culture medium.

Betaxolol-induced deterioration of asthma and a pharmacodynamic analysis based on beta-receptor occupancy

OBJECTIVE

To report a case of deterioration of asthma associated with continuous use of oral betaxolol, a beta1-selective beta-blocking agent. We also analyzed the pharmacokinetics in this case by applying a receptor occupancy model.

CASE SUMMARY

A 68-year-old woman taking 5 mg of betaxolol for hypertension occasionally experienced asthmatic coughing after upper respiratory tract infection. Two years after the start of betaxolol, her asthma gradually worsened. Although pharmacotherapy for asthma was introduced, betaxolol was continued. Finally, she was admitted to hospital with bronchospasm. When she was discharged after 2 months, betaxolol was discontinued and losartan potassium (25 mg/d) was initiated instead for her hypertension. Since then, she has been free from bronchospasm.

METHOD

We calculated the mean receptor occupancy (phiSS) of the beta1- and beta2-receptors after the usual oral dose of betaxolol by using pharmacokinetic-pharmacodynamic parameters obtained from the literature. We estimated the decrease in the exercise pulse rate or the forced expiratory volume in 1 second (FEV1) by applying the phiSS values to the model previously reported by us.

RESULTS

Betaxolol seems less likely than other beta1-blocking agents to cause pulmonary adverse effects. However, the estimated decrease in FEV1 after oral administration of betaxolol (5 mg) was close to that after oral bisoprolol (5 mg), which has been reported to induce asthma.

CONCLUSIONS

Oral betaxolol may induce bronchospasm, although betaxolol is considered to be highly cardioselective and seems less likely than other beta1-selective blocking agents to cause pulmonary adverse effects. Betaxolol should be administered with caution to patients with asthma or chronic pulmonary disease.

Urinary excretion of selegiline N-oxide, a new indicator for selegiline administration in man

1. The metabolism of selegiline (SG) has been studied by investigating the time-course of urinary excretion of SG and its metabolites using high-performance liquid chromatography-electrospray ionization mass spectrometry (LC-ESI MS) in combination with solid-phase extraction. 2. The excretion profiles of SG and its four major metabolites, selegiline-N-oxide (SGO), N-desmethylselegiline (DM-SG), methamphetamine (MA) and amphetamine (AP), were investigated in six healthy volunteers after oral administrations of SG hydrochloride in a single dose of 2.5 or 7.5mg, and a repeat twice-daily dose of 5.0 mg day(-1) (for 3 days). 3. The cumulative amount of SGO excreted within approximately the first 8-12h was comparable with MA, and the amount in the first 72 h was 2.0-7.8 times larger (2.8-13.2% of the dose) than that of DM-SG. 4. These results demonstrate that SGO can be used in place of DM-SG, which is known to be a main specific metabolite of SG, as a new indicator for the discrimination of SG use compared with MA abuse.

Functional magnetic resonance imaging of the visual system

Functional magnetic resonance imaging (fMRI), which is a technique useful for non-invasive mapping of brain function, is well suited for studying the visual system. This review highlights current clinical applications and research studies involving patients with visual deficits. Relevant reports regarding the investigation of the brain's role in visual processing and some newer fMRI techniques are also reviewed. Functional magnetic resonance imaging has been used for presurgical mapping of visual cortex in patients with brain lesions and for studying patients with amblyopia, optic neuritis, and residual vision in homonymous hemianopia. Retinotopic borders, motion processing, and visual attention have been the topics of several fMRI studies. These reports suggest that fMRI can be useful in clinical and research studies in patients with visual deficits.

Herbal medicines, Sairei-to and Tokishakuyaku-san, differently modulate the release of cytokines from decidual versus peripheral blood mononuclear cells

PROBLEM AND METHOD OF STUDY

We have shown that Tokishakuyaku-san (Toki) and Sairei-to (Sai) enhance T helper-1 (Th1) cytokine release from peripheral blood mononuclear cells (PBMCs): thereby, they could be a therapeutic means in the treatment of autoimmunity related recurrent abortion in which T helper-2 (Th2) polarization is exaggerated, the condition purported to benefit from these herbal medicines. However, an open question is whether these medicines might enhance Th1 cytokine release in decidual tissues and thereby stimulate the killer activity, thus, working counterproductively by accelerating maternal alloimmune reactions toward fetal tissues. To address this, we examined the effects of these medicines on the release of cytokines from decidual mononuclear cells (DMCs) in comparison with PBMCs on the assumption that they might act differently on these cell types. The effects of these medicines were investigated as related to human leukocyte antigen (HLA)-G, a nonclassical HLA class I antigen expressed on trophoblasts and a putative crucial player involved in fetomaternal immune interplay.

RESULTS

Regarding Th1 cytokines. Toki marginally increased the release of tumor necrosis factor (TNF)-alpha, but not interferon (IFN)-gamma from DMCs while Sai did not affect the release of both. Both Toki and Sai were without effect in modulating the release of interleukin (IL)-4, a member of Th2 cytokines. Interestingly, the presence of HLA-G reduced the release of Th1 cytokines from DMCs regardless of the addition of Toki, Sai or none. These findings are in sharp contrast with PBMCs on which these medicines seem to act so as to enhance Th1 polarization and attenuate Th2 polarization.

CONCLUSION

Differential effects of Toki and Sai on the release of Th1/Th2 cytokines between DMCs and PBMCs may afford the rationale of these medicines in the treatment of autoimmunity-related recurrent abortion.

Functional magnetic resonance imaging of eye dominance at 4 tesla

We studied eye dominance in visual cortex and lateral geniculate nucleus (LGN) using functional magnetic resonance imaging (fMRI) at a very high magnetic field (4 tesla). Eight normal volunteers were studied with fMRI at 4 tesla during alternating monocular visual stimulation. The acquisition was repeated twice in 4 subjects to confirm reproducibility. In addition, magnetic resonance signal intensities during three conditions (right eye stimulation, left eye stimulation, and control condition) were compared to determine whether the observed area was truly or relatively monocular in 2 subjects. In both the individual and group analyses, the anterior striate cortex was consistently activated by the contralateral eye more than the ipsilateral eye. Additionally, we found evidence that there were areas in the bilateral LGN which were more active during the stimulation of the contralateral eye than during the stimulation of the ipsilateral eye. The activated areas were reproducible, and the mean ratio of the overlapping area was 0.71 for the repeated scans. The additional experiment revealed that the area in the anterior visual cortex could be divided into two parts, one truly monocular and the other relatively monocular. Our finding confirmed previous fMRI results at 1.5 tesla showing that eye dominance was observed in the contralateral anterior visual cortex. However, the eye dominance in the visual cortex was found not only in the most anterior area corresponding to the monocular temporal crescent but also in the more posterior area, presumably showing the greater sensitivity of the temporal visual field (nasal retina) as compared with the nasal visual field (temporal retina) in the peripheral visual field (peripheral retina). In addition, it is suggested that the nasotemporal asymmetry of the retina and the visual fields is represented in the LGN as well as in the visual cortex.

Simultaneous determination of selegiline-N-oxide, a new indicator for selegiline administration, and other metabolites in urine by high-performance liquid chromatography-electrospray ionization mass spectrometry

In order to discriminate selegiline (SG) use from methamphetamine (MA) use, the urinary metabolites of SG users have been investigated using high-performance liquid chromatography (HPLC)-electrospray ionization mass spectrometry (HPLC-ESI-MS). Selegiline-N-oxide (SGO), a specific metabolite of SG, was for the first time detected in the urine, in addition to other metabolites MA, amphetamine (AP) and desmethylselegiline (DM-SG). A combination of a Sep-pak C18 cartridge for the solid-phase extraction, a semi-micro SCX column (1.5 mm I.D.x 150 mm) for HPLC separation and ESI-MS for detection provided a simple and sensitive procedure for the simultaneous determination of these analytes. Acetonitrile-10 mM ammonium formate buffer adjusted to pH 3.0 (70:30, v/v) at a flow-rate of 0.1 ml/min was found to be the most effective mobile phase. Linear calibration curves were obtained over the concentration range from 0.5 to 100 ng/ml for all the analytes by monitoring each protonated molecular ion in the selected ion monitoring (SIM) mode. The detection limits ranged from 0.1 to 0.5 ng/ml. Upon applying the scan mode, 10-20 ng/ml were the detection limits. Quantitative investigation utilizing this revealed that SGO was about three times more abundant (47 ng/ml, 79 ng/ml) than DM-SG in two SG users' urine samples tested here. This newly-detected, specific metabolite SGO was found to be an effective indicator for SG administration.

Effect of eicosapentaenoic acid (EPA) on tight junction permeability in intestinal monolayer cells

The purpose of this study is to evaluate the effect of C18 and C20 long chain fatty acids on tight junction permeability in a model of intestinal epithelium.

METHODS

Confluent Caco-2 cells on porous filters with double chamber system were used to measure fluorescein sulfonic acid (FS) permeability and transepithelial electrical resistance (TEER). Lactate dehydrogenase release and ultrastructure were evaluated. Effect of 200 microM eicosapentaenoic acid (EPA, C20:5 n-3), arachidonic acid (AA, C20: 4 n-6), alpha-linoleic acid (ALA, C18: 3 n-3), linoleic acid (LA, C18: 2 n-6), or oleic acid (OA, C18: 1 n-9) enrichment in the culture medium during 24 hours were compared. The effect of the cyclooxygenase inhibitor, indomethacin, lipoxygenase inhibitors, NDGA or AA861, and antioxidant, BHT, was evaluated as a mechanism to change tight junction permeability.

RESULTS

Caco-2 cells formed polarized columnar epithelial cells with densely packed microvilli and well developed junctional complexes. Addition of EPA enhanced FS permeability to 3.0+/-1.6-fold and lowered TEER to 0.59+/-1.2-fold vs. control with concentration dependency without cell injury (P<0.01-0.05). OA, AA or LA did not change, but ALA enhanced tight junction permeability. Indomethacin and AA861 normalized the changes mediated by EPA.

CONCLUSIONS

EPA affects tight junction permeability in intestinal monolayer cells specifically and concentration dependently via cyclooxygenase and lipoxygenase products.

Adaptive changes in dynamic properties of human disparity-induced vergence

PURPOSE

Vergence eye movements undergo adaptive recalibration in response to a training stimulus in which the initial disparity is changed just after vergence begins (the double-step paradigm). In the present study the changes in the dynamic properties of convergence, speed and acceleration, were examined by using this double-step paradigm, before and after adaptation.

METHODS

Four normal subjects participated. Three-dimensional visual stimuli were provided by a head-mounted display with two liquid crystal diode (LCD) panels. To induce adaptation, a double step of disparity was used: an initial step from distances of 2 to 1 m was followed by a second step to distances of 0.7 m ("increasing paradigm") or 1.4 m ("decreasing paradigm") after a constant period of 0.2 seconds. The dynamic properties of vergence were compared before and after 30 minutes of training with these paradigms.

RESULTS

Peak velocity of convergence became significantly greater (increasing paradigm) or smaller (decreasing paradigm) after 30 minutes' training. Changes in the dynamic properties of convergence were also obvious in phase-plane (velocity versus position) and main sequence (peak velocity versus amplitude) plots. Further analysis revealed that adaptive increases in vergence velocity were accomplished by an increase in the duration of the acceleration period, whereas adaptive decreases were induced by a decrease in the maximum value of acceleration.

CONCLUSIONS

The pattern of change in the dynamic characteristics of vergence after adaptation was similar to that of saccades and the initiation of pursuit eye movements, suggesting common neural mechanisms for adaptive changes in the open-loop control of eye movements.

Effects of check size on visual cortex activation studied by functional magnetic resonance imaging

We studied functional magnetic resonance imaging (fMRI) of visual cortex during checkerboard visual stimulation with three standard check sizes to examine whether activation in the visual cortex varied among these sizes. We acquired fMRI at 1.5 T in 8 normal subjects, each receiving the best refractive correction. Each subject underwent an experiment consisting of four conditions: black and white checkerboards with three check sizes (0.25-, 0.5-, and 1.0-degree) flickering at 8 Hz, and a black screen. SPM96 was used for a group data analysis with a random effects model after each of the subject's data was motion-corrected and spatially normalized to a standard brain. The activation in the visual cortex showed the greatest signal changes with the 0.5-degree check among the three check sizes. When standard check sizes are used to stimulate visual cortex in fMRI experiments, our results suggest that 0.5-degree checks flickering at 8 Hz produce the most vigorous activation in visual cortex.

Pigeons' timing of an arbitrary and a naturalistic auditory stimulus: tone versus cooing

Previous animal research has traditionally used arbitrary stimuli to investigate timing in a temporal bisection procedure. The current study compared the timing of the duration of an arbitrary, auditory stimulus (a 500-Hz tone) to the timing of the duration of a naturalistic, auditory stimulus (a pigeon cooing). In the first phase of this study, temporal perception was assessed by comparing psychophysical functions for the duration of tone and cooing signals. In the first set of tests, the point of subjective equality (PSE) was significantly lower for the tone than for the cooing stimulus, indicating that tones were judged longer than equivalent durations of cooing. In the second set of tests, gaps were introduced in the tone signal to match those present in the cooing signal, and no significant difference in the PSE for the tone or the cooing signal was found. A repetition of the testing conducted with gaps removed from the tone signal, failed to replicate the difference in the PSEs for the tone and cooing signals originally obtained. In the second phase of the study, memory for the duration of tone and cooing was examined, and a choose-long bias was found for both signals. Based on these results, it appears that, for pigeons, there may be no significant differences in either temporal perception or temporal memory for arbitrary, auditory signals and more complex, naturalistic, auditory signals.

Reproducibility of visual activation during checkerboard stimulation in functional magnetic resonance imaging at 4 Tesla

PURPOSE

To investigate the reproducibility of visual activation by checkerboard stimulation, we used functional magnetic resonance imaging (fMRI) at 4 Tesla (T).

METHODS

Four subjects were studied with fMRI at 4 T during checkerboard visual stimulation. The functional images were realigned and spatially normalized to the standard brain. For each subject, statistical parametric maps were made for each study, and the reproducibility was determined based on the number of supra-threshold voxels (Z > 3.5, 4.5, and 5.5).

RESULTS

The mean ratio for the number of supra-threshold (Z > 4.5) voxels was 0.75, and the mean ratio for the overlapping voxels was 0.61. Restricting the region of interest within the posterior half of the brain improved reproducibility values at the low threshold (Z > 3.5), but did not improve the values at the higher thresholds.

CONCLUSIONS

Despite the fact that more than half of the supra-threshold voxels were found to be active for the repeated scans, visual activation with checkerboard stimulation seems to be less reproducible than that by flash stimulation.

Polymorphism of human leukocyte antigen-E gene in the Japanese population with or without recurrent abortion

PROBLEM

The aim of this study was to investigate the gene frequencies and shared alleles of human leukocyte antigen (HLA)-E gene in Japanese couples with or without recurrent abortion.

METHOD OF STUDY

Polymerase chain reaction (PCR)-single strand conformation polymorphism (SSCP) analysis was carried out to detect polymorphism in exon 3 of the HLA-E gene in 30 Japanese couples with recurrent abortion and 38 normal Japanese couples with proven fertility.

RESULTS

No point mutation was detected in exon 3 of HLA-E in both recurrent aborters and normal controls. HLA-EG and HLA-ER alleles were detected with frequencies of 66.7% and 33.3% in couples with recurrent abortion and 69.2% and 30.8 in normal couples, respectively. The gene frequency of HLA-EG was higher than that of HLA-ER, which is contrary to that found in Caucasian, African-American and Hispanic people but similar to Chinese people. The frequency of each allele was not significantly different between recurrent aborters and normal controls. The number of shared alleles between each couple with recurrent abortion is not significantly different from that with normal controls.

CONCLUSION

Allele frequencies of HLA-E were suggested to be different in Asian people from those in other ethnic people. In light of no specific distribution pattern in recurrent aborters, HLA-E polymorphism does not seem to play a role in the pathogenesis of recurrent abortion.

Ocular dominance in anterior visual cortex in a child demonstrated by the use of fMRI

Negative signal changes in the visual cortex have been observed during visual stimulation when performing functional magnetic resonance imaging (fMRI) in children. This report investigated whether the ocular dominance, which has been demonstrated in the contralateral anterior visual cortex in adults, could be observed in a child by the use of fMRI. A 5-year-old child was studied using fMRI at 1.5 T during alternating monocular visual stimulation under sedation with morphine and pentobarbital. The functional images were motion corrected, and statistical parametric maps were made by contrasting the left or right eye stimulation conditions vs the right or left eye stimulation conditions, respectively, at each voxel. Areas with negative signal changes were found on the left anterior visual cortex during monocular visual stimulation of the right eye and vice versa. There was no area with negative or positive signal change on the ipsilateral visual cortex to the stimulated eye and no area with positive signal change on the contralateral visual cortex. Contralateral ocular dominance of anterior visual cortex similar to that of adults was demonstrated in this child with a negative correlation with the visual stimulus. This finding suggests that peripheral visual fields are represented in the anterior visual cortex of 5-year-old children.