Effectiveness of patient and staff cohorting to reduce the risk of vancomycin-resistant enterococcus (VRE) acquisition: a retrospective cohort study during a VRE outbreak in Japan

BACKGROUND

Patient and staff cohorting is part of a bundle approach in the response to multi-drug-resistant organisms, but its effectiveness is not fully clarified. This study compared the risks of acquiring vancomycin-resistant Enterococcus faecium (VREfm) at a hospital during a VREfm outbreak based on contact characteristics in order to better understand the effectiveness of cohorting.

METHODS

Exposure came from contact with patients with VREfm (infectors), including existing patients with VREfm and patients who acquired VREfm during the study period. Contact was defined as length of contact time, degree of sharing space, and care by the same nurses as those caring for infectors between January and March 2018. The outcome was VREfm acquisition as determined through monthly stool or rectal screening cultures. Incidence rates were calculated based on contact patterns, and incidence rate ratios (IRRs) were compared.

FINDINGS

Among 272 inpatients (4038 patient-days), 43 patients acquired VREfm with the same or similar pulsotype. Incidence rates were 8.45 per 1000 patient-days when susceptible inpatients were on the same ward as an infector but cared for by different nurses (reference), 16.96 when susceptible inpatients were on the same ward as an infector and cared for by the same nurses [IRR 2.01, 95% confidence interval (CI) 0.62-10.28], and 52.91 when susceptible inpatients shared a room with an infector (IRR 6.26, 95% CI 1.61-35.40).

CONCLUSION

Compared with susceptible inpatients in a different room from infectors and not being cared for by the same nurses, the risk of VREfm acquisition could be six times higher for susceptible inpatients who are in the same room as infectors, and could be double for susceptible inpatients cared for by the same nurses as infectors.

Effects of the time-of-day (morning vs. afternoon) of implementing a combined physical and cognitive exercise program on cognitive functions and mood of older adults: A randomized controlled study

This study examined the effects of the time of conducting a combined physical and cognitive exercise program on cognitive functions and the mood of older adults. We randomly assigned 17 participants (8 men, 9 women, age 73,24±3,75) to the morning group (AM Group), 18 (8 men, 10 women, age 73,11±4,84) to the afternoon group (PM Group), and they completed a 12-week, dual-task exercise program in the morning or the afternoon, respectively. Moreover, the waiting-list control group consisted of 12 participants (6 men, 6 women, age 73,25±5,93). The cognitive functions and the mood of the participants were assessed before and after the program by using the Neurobehavioral Cognitive Status Examination, and the short version of the Profile of Mood States, respectively. As a result, the exercise program conducted in the afternoon had broader effects on cognitive functions (increased Repetition and Memory) than in the morning (increased Repetition), or the waiting-list control group (increased Judgment). Moreover, the program in the afternoon tended to reduce Anger-Hostility, and Fatigue. In conclusion, conducting the exercise program in the afternoon might be more effective for improving cognitive functions and the mood of older adults than in the morning. However, there was heterogeneity between the groups despite the randomization. Therefore, we suggest conducting a more rigorously controlled study using a larger sample to validate these findings.

Supramolecular chemistry of pillar[n]arenes functionalised by a copper(i)-catalysed alkyne-azide cycloaddition "click" reaction

Since we discovered pillar[n]arenes in 2008, many chemists have developed a strong interest in pillar[n]arene chemistry because of the many advantages associated with these materials, including their facile and high yielding synthesis, versatile functionality, planar chirality and unique host-guest properties. In this feature article, we discuss recent advances in the field of supramolecular chemistry based on the use of pillar[n]arenes as substrates for copper(i)-catalysed alkyne-azide cycloaddition (CuAAC) "click" chemistry. The CuAAC reaction provides facile access to 1,4-disubstituted triazoles by a reaction between alkyne and azido substrates in the presence of a Cu(i) catalyst. Pillar[n]arenes bearing alkyne or azido groups can therefore be used as substrates for this reaction. Herein, we discuss not only the synthesis of pillar[n]arenes bearing alkyne or azido groups but also the application of these functionalised systems to the CuAAC reaction to construct supramolecular assemblies. We also discuss the rational molecular design and synthesis of guest compounds using the CuAAC reaction because linear alkanes sandwiched between 1,2,3-triazole moieties are good guests for cyclic pentamer pillar[5]arenes.

Effects of reduced-volume of sprint interval training and the time course of physiological and performance adaptations

This study sought to determine the time course of training adaptations to two different sprint interval training programmes with the same sprint: rest ratio (1:8) but different sprint duration. Nine participants (M: 7; F: 2) were assigned to 15-second training group (15TG) consisting of 4-6 × 15-second sprints interspersed with 2-minute recovery, whereas eight participants (M: 5; F: 3) were assigned to 30-second training group (30TG) consisting of 4-6 × 30 second sprints interspersed with 4-minute recovery. Both groups performed their respective training twice per week over 9 weeks and changes in peak oxygen uptake (V˙O2peak) and time to exhaustion (TTE) were assessed every 3 weeks. Additional eight healthy active adults (M: 6; F: 2) completed the performance assessments 9 weeks apart without performing training (control group, CON). Following 9 weeks of training, both groups improved V˙O2peak (15TG: 12.1%; 30TG: 12.8%, P<.05) and TTE (15TG: 16.2%; 30TG: 12.8%, P<.01) to a similar extent. However, while both groups showed the greatest gains in V˙O2peak at 3 weeks (15TG: 16.6%; 30TG: 17.0%, P<.001), those in TTE were greatest at 9 weeks. CON did not change any of performance variables following 9 weeks. This study demonstrated that while the changes in cardiorespiratory function plateau within several weeks with sprint interval training, endurance capacity (TTE) is more sensitive to such training over a longer time frame in moderately-trained individuals. Furthermore, a 50% reduction in sprint duration does not diminish overall training adaptations over 9 weeks.

Selective Play: Choosing Partners in an Uncertain World

The theoretical implications of introducing the “selective play” paradigm to experimental gaming research are discussed. In the traditional “forced play” environment, players are locked in a particular relationship and do not have options of leaving the current relationship and joining another. In the selective play environment players are given the options of leaving the current relationship andforming a new relationship. A previous computer tournament of prisoner's dilemma network (Hayashi, 1993) showed that out-for-tat (OFT) strategy performed very well in the selective play environment. OFT keeps cooperating with a partner until the partner defects; it deserts the partner and turns to someone else as soon as the partner defects. Results of a new computer tournament that introduced opportunity costs, however, point to the limits of the OFT's strength. OFT prematurely forms a commitment relationship with a cooperative partner and fails to utilize better opportunities. The best performer in the second tournament was the only one who was “trustful” and had a positive bias in calculating the expected payoff of interactions with a “stranger.”

Successful control of an outbreak of GES-5 extended-spectrum β-lactamase-producing Pseudomonas aeruginosa in a long-term care facility in Japan

BACKGROUND

Little is known about multidrug-resistant Pseudomonas aeruginosa (MDRP) outbreaks in long-term care facilities (LTCFs).

AIM

To describe an MDRP outbreak in an LTCF and to clarify risk factors for MDRP acquisition.

METHODS

Patients who were positive for MDRP at an LTCF from January 2013 to January 2014 were analysed. A descriptive analysis, a case-control study, and a microbiological analysis were performed.

FINDINGS

A total of 23 MDRP cases were identified, 16 of which were confirmed in sputum samples. Healthcare workers were observed violating hand hygiene procedures when performing oral, wound, and genital care. Nasogastric tube and oxygen mask use was associated with MDRP acquisition in the respiratory tract, which might have been confounded by poor hand hygiene. Sharing unhygienic devices, such as portable oral suction devices for oral care, and washing bottles and ointments for wound and genital care with inadequate disinfection could explain the transmission of MDRP in some cases. Isolates from 11 patients were found to be indistinguishable or closely related by pulsed-field gel electrophoresis and harbouring the blaGES-5 gene. Subsequent enhanced infection control measures were supported by nearby hospitals and a local public health centre. No additional cases were identified for a year after the last case occurred in January 2014.

CONCLUSION

An outbreak of MDRP with an antimicrobial resistance gene, blaGES-5, occurred in a Japanese LTCF. It was successfully controlled by enhanced infection control measures, which neighbouring hospitals and a local public health centre supported.

[A patient with advanced breast cancer who developed bacterial meningitis after chemotherapy]

A 76-year-old woman was admitted to our hospital because of a right breast tumor and a skin ulcer. The patient was diagnosed as having advanced breast cancer T4bN2M1(lung), Stage IV. A regimen of 5-fluorouracil(500mg/m2)with epirubicin(100mg/m / 2)and cyclophosphamide(500mg/m2)(FEC100)was administered. However, the patient was hospitalized 12 days later because of febrile neutropenia. The patient experienced a stiff neck the next day, and bacterial meningitis was diagnosed on the basis of cerebrospinal fluid examination. Antibacterial agents were administered according to the clinical practice guidelines of bacterial meningitis. The patient recovered and was discharged from our hospital 24 days after admission. Bacterial meningitis after chemotherapy is rare, but this could be progress to a serious condition. Early diagnosis and treatment are paramount in such cases.

Pillar[5]- and pillar[6]arene-based supramolecular assemblies built by using their cavity-size-dependent host–guest interactions

We discuss various pillar[5]- and pillar[6]arene-based supramolecular assemblies built using their host–guest interactions.

Cryopreservation of the model alga Ectocarpus (Phaeophyceae)

The brown alga Ectocarpus has recently become the first fully sequenced multicellular alga and is an important biological model. Due to the large and growing number of Ectocarpus strains isolated and maintained by the research community, including increasing numbers of mutants, there is an urgent need for developing reliable, cost-effective long-term maintenance techniques. We report here that cryopreservation constitutes an attractive option in this respect, using a simple two-step protocol employing combined DMSO 10 percent (v/v) and sorbitol 9 percent (w/v) as cryoprotectants. This model organism appears to be remarkably robust and post-cryo recovery has been observed in all strains tested in this study. Cultures can be regenerated by the germination of cryopreserved zooids (spores), or the recovery of vegetative cells. In the latter case, dividing surviving cells may grow into the cell lumen of a neighbouring dead cell, eventually regenerating a phenotypically normal thalloidal structure.

SU-E-T-497: Study of Restricted Mass Stopping Power Ratio in Small Electron Tube Fields

PURPOSE

Electron tubes with small radii are useful to treat narrow regions which cannot accommodate normal electron applicators. In small electron fields, it is not trivial to estimate restricted mass stopping power ratio (MSR), which is needed to evaluate dose from ion chamber measurement. We studied MSRs in small electron tube fields using the Monte Carlo simulation.

METHODS

Electron tubes with radii, 3 and 2.5 cm, were used in this study. Nominal electron energies were 6 and 9 MeV. There were two types of tubes. One has a normal cut but the other has a 45-degree cut. For the normal cut tube, percent depth dose (PDD) in water was evaluated along the center of axis (CAX) of a beam. For the 45-degree cut tube, PDD was evaluated along the vertical line from the intersection of the CAX and the phantom surface with 45-degree gantry angle. The MSRs and mean electron energies were calculated using the Monte Carlo simulation.

RESULTS

We found good agreement between the measured and calculated PDDs. The changes of mean energies from those in the 10×10 cm² field at the depth of maximum dose (dmax) were very small for the normal cut electron tubes. For the 45-degree cut tubes, the changes of mean energies at dmax were less than 1 MeV. The MSRs in the normal cut tube fields were almost the same as those in the 10×10 cm² field at the corresponding depths. The MSRs for the 45-degree cut tubes deviated from those in the 10×10 cm² by about 1% (1.5 % at most).

CONCLUSIONS

We evaluated the mean energies and MSRs in small electron tube fields. The deviations of them from the values in the 10×10 cm² were small. The maximum difference of MSR was 1.5% in 45-degree cut tube fields. This work was supported by KAKENHI (23791449), Japan Society for the Promotion of Science, and Cancer Professional Training Plan, The Ministry of Education, Culture, Sports, Science and Technology, Japan.

Evaluation of unexpected positive results from a commercial ELISA for antibodies to PRRSV

Unexpected positive results from the widely used IDEXX ELISA for the detection of antibodies to porcine reproductive and respiratory syndrome virus (PRRSV) may confound investigations of the disease. Supplementing the ELISA with blocking agents and the use of IgG purified from serum samples had no effect on the unexpected positive results, suggesting that they were due to an antibody-antigen reaction. Simple competitive and blocking ELISAs were developed by modifying the IDEXX ELISA, and they and an indirect fluorescent antibody test (IFAT) were used to examine PRRSV antibodies in 33 antibody-negative, 88 antibody-positive and 73 unexpectedly positive sera. All the unexpectedly positive sera were negative by IFAT, and 89.0 per cent were negative by both the competitive and blocking ELISAs. The competitive ELISA (97.7 per cent) and the blocking ELISA (96.5 per cent) detected more positive sera than the IFAT (90.9 per cent). These results show that both ELISAs are capable of distinguishing positive and unexpectedly positive sera, and suggest that most of the unexpected positive signals are false-positives.

Changes in evaluation of the pepsinogen test result following Helicobacter pylori eradication therapy in Japan

AIMS

The pepsinogen (PG) test result is used in Japan for screening for gastric cancer. In this study, we investigated the changes in evaluation of the PG test result following H. pylori eradication.

METHODS

The subjects were 120 consecutive H. pylori-positive patients with upper gastrointestinal symptoms. Subjects underwent endoscopy prior to, and at 2 months after the eradication therapy, at which time blood was taken for determination of changes in PG levels.

RESULTS

The overall eradication rate was 79.3% (per protocol). Following eradication therapy, the evaluation of PG test result converted from positive to negative in 80.4% (37/46) of cases of successful eradication, and in 0% (0/6) of cases of eradication failure.

CONCLUSIONS

These results suggest that the evaluation of PG test result should be used after the definitive confirmation of the success or failure of H. pylori eradication therapy.

Carotid artery calcification seen on panoramic dental radiographs in the Asian population in Japan

OBJECTIVES

To determine the frequency of carotid artery calcification (CAC) seen on panoramic dental radiographs, the relationship between the condition and a history of cerebral infarction (CI), and the history of the risk factors of CI in patients in Japan.

METHODS

A total of 2374 individuals whose panoramic radiographs were obtained at their first consultation were reviewed.

RESULT

CAC was found in 95 subjects (4.0%) and was found at a higher frequency in patients with a history of CI than in those without a history of CI. The modifiable risk factors (a history of hypertension, diabetes and hypercholesterolaemia) and CAC showed significant relationship in the chi(2) test for pairwise comparison. When age and gender were added and all of these risk factors were considered simultaneously in the multiple logistic regression analysis, age and history of hypercholesterolaemia remained statistically significant.

CONCLUSIONS

CAC may be seen on panoramic dental radiographs and is related to the patients' general history of CI, and the risk factors of CI in the Asian population in Japan.

Various Streptococcus species isolated from infectious skin diseases

An evaluation was carried out of the types of Streptococcus spp. (excluding Streptococcus pyogenes) isolated from infectious skin diseases, and their susceptibilities to eight antimicrobial drugs of the Streptococcus spp. isolated. The types of diseases were also evaluated. A total of 29 Streptococcus spp. were identified and Streptococcus agalactiae was the most common. Streptococcus spp. were found to be susceptible to the eight antimicrobials used except gentamicin; susceptibility to gentamicin varied according to species. Susceptibility to beta-lactams was 100% and this drug should be considered the antimicrobial of choice in Streptococcus spp. treatment.

Isolation of Enterococcus species from infectious skin lesions

Enterococcus faecalis was isolated at a frequency of 70% and was chiefly isolated from secondary infections due to ulcer/decubitus. Seven sole/predominant E. faecalis were isolated. Penicillins were more effective against E. faecalis and the sensitivities of E. faecalis to antimicrobials were higher than those of E. faecium. Some nonpredominant E. faecalis strains were sensitive to erythromycin probably due to less resistant mechanisms. The characterization of Enterococcus spp. is especially important when choosing appropriate antimicrobials for therapy.

Effect of lipase activities of Propionibacterium granulosum and Propionibacterium acnes

We studied the lipase activities of Propionibacterium granulosum, P. acnes and the suppression of these activities by Jumi-haidoku-to (JHT). Lipase activity of P. acnes biotype III (BIII) was strongest, while that of P. granulosum was faintly expressed. Compared with the control medium, the production of propionic and butyric acids was suppressed by all the tested mediums combined with JHT. The decrease in these acids produced by JHT was significantly higher in P. granulosum than in P. acnes. Although P. acnes BIII may produce a strong effect on acne, the presence of P. granulosum should not be ignored. Further research is required on the correlation between P. acnes and P. granulosum.

[Coronary artery bypass grafting in octogenarian]

Coronary artery bypass graftings (CABG) in elderly patients are increasing in recent years. Several studies have shown that the rate of complications and mortality is higher in elderly patients than in younger ones. This report presents results of CABG in octogenarians. From January 1996 to December 1999, 362 patients underwent isolated CABG, of whom 15 were over 80 years old (80-year group) and 122 were 70-79 years old (70-year group). Preoperative cardiac function was worse in the 80-year group than in 70-year group [60% vs 29% in Canadian Cardiovascular Society (CCS) class III or IV]. No significant difference was found between two groups in extracorporeal circulation time, aortic clamp time, the number of bypasses and postoperative complications. We conclude that CABG should not be excluded in octogenarians because of their chronological age alone.

Characteristics of Pseudomonas aeruginosa isolated from skin infections

From January 1995 to June 2000, 19 Pseudomonas aeruginosa were detected in 19 cases of infectious skin diseases. Coagulase-negative staphylococci coexisted with P. aeruginosa in 10 cases and P. aeruginosa was also often associated with Enterococcus sp., Staphylococcus aureus, Streptococcus sp. or other species. Twelve cases carried P. aeruginosa more predominantly than the other species. Some coagulase-negative staphylococci, Enterococcus sp., S. aureus and Streptococcus sp. were also predominant. The frequency of predominant P. aeruginosa was significantly higher in secondary infections due to ulcers and decubitus than in secondary infections due to other skin diseases. P. aeruginosa was also often detected in the legs and feet, but not in the trunk. This organism showed high sensitivities to antibiotics, except minocycline. No significant differences in sensitivity or resistance to antibiotics were found between P. aeruginosa when detected as the predominant or single strain and this microorganism when detected as the non-predominant strain. Thus, the detection of P. aeruginosa important in choosing the appropriate antibiotics to be used and this is sometimes influenced by the patient's condition.

Developing and sustaining 3-chlorophenol-degrading populations in up-flow anaerobic column reactors under circum-denitrifying conditions

Microbial consortia capable of degrading 3-chlorophenol (3-CP) were enriched in continuous up-flow column reactors under circum-denitrifying conditions. 3-CP degradation capability was developed and sustained when 3-CP was supplied at 16-21 microM, although suppression of the 3-CP degradation capability was observed when 3-CP was supplied at 42 microM. When 3-CP was stably degraded, the ratio of nitrate consumption to 3-CP degradation approached the theoretical stoichiometric value, which was calculated by assuming a 3-CP degradation-dependent nitrate reduction. Batch-incubation experiments demonstrated that the microbial consortium that was enriched in the column reactors required either nitrate or oxygen for degrading 3-CP, while 3-CP was not degraded under sulfate-degrading conditions. Although many attempts were made to sustain the microbial 3-CP degradation capability under denitrifying conditions, mostly in batch cultures, none of them have been successful so far. Therefore, the results obtained in this study may be the first to demonstrate sustainable 3-CP degradation capability under circum-denitrifying conditions.

Lung impairment following cardiac surgery in patients with pulmonary hypertension

BACKGROUND

Postoperative respiratory management following cardiac surgery is sometimes troublesome in patients with pulmonary hypertension. We retrospectively studied the relationship between the etiology of preoperative pulmonary hypertension and the postoperative decline of blood oxygenation capacity by focusing on the postoperative intravascular fluid volume.

METHODS

Sixteen adult patients with an atrial septal defect (preload group) and 17 patients with solitary mitral valve disease (afterload group) were studied. The mean age of the patients in the preload and afterload group was 51 and 52 years old, respectively.

RESULTS

Preoperative pulmonary-systemic pressure ratio and pulmonary artery resistance index were significantly higher in the preload group than in the afterload group. The respiratory index (RI) and the pulmonary shunt ratio (Qs/Qt) measured immediately after the operation was larger in the afterload group than in the preload group. Postoperative RI and Qs/Qt remained high until postoperative day 3 in both groups. In the preload group RI on postoperative day 1 had a reverse correlation with the central venous pressure (CVP). Meanwhile, the RI in the afterload group on postoperative day 1 was slightly larger in patients with a high CVP and pulmonary capillary wedged pressure. Similar relationships were seen in the relations between pulmonary capillary wedged pressure and RI in the afterload group. CONCLUSIONS In conclusion, a preoperative pulmonary vascular change and a postoperative precipitous decrease of pulmonary blood flow may have caused postoperative lung oxygenation impairment in the preload group. An extended period of extracorporeal circulation associated with cardiac arrest and postoperative volume overload may have caused lung impairment in the afterload group. In aspect of postoperative management, low CVP is beneficial to the patients in the afterload group, however, hypovolemia should be avoided in patients of the preload group.

Tamoxifen agonism and estrogen antagonism of c-fos gene promoter activity through non-consensus-responsive elements in MC3T3-E1 osteoblasts

We find that the activity of a 0.4-kb human c-fos gene promoter (-404/+41), which lacks consensus estrogen-responsive elements (EREs), is regulated by estrogen receptor (ER) ligands in MC3T3-E1 osteoblastic cells through ERs in a manner distinct from ERE-mediated regulation. When ERalpha is coexpressed, both estrogens and antiestrogens upregulate promoter activity. When ERbeta is coexpressed, however, three tested antiestrogens affect c-fos promoter activity, with tamoxifen exerting the greatest effect, while estrogens have no such effect. The tamoxifen agonism through ERbeta is antagonized by 17beta-estradiol, while the 17beta-estradiol agonism through ERalpha is canceled by excess-level coexpression of ERbeta. Deletion analysis revealed that the sequence -206/-110 plays a crucial role in the ERbeta-mediated tamoxifen agonism. Interestingly, there is no ERbeta-mediated tamoxifen agonism when nonosteoblastic cells are tested. Taken together, these results suggest that the transcription of the c-fos gene is regulated by ER ligands possibly through non-ERE elements in ligand structure-, cell type-, and ER subtype-dependent manners.

Expression of bone morphogenetic protein-5 gene during chick heart development: possible roles in valvuloseptal endocardial cushion formation

The bone morphogenetic protein (BMP) family, comprising multifunctional peptide growth factors, regulates many developmental processes in a variety of tissues. We examined the spatiotemporal expression of BMP5 by in situ hybridization in chick embryonic hearts from stages 5 to 33. The BMP5 gene was first expressed in the endoderm underlying the precardiac mesoderm at stages 5 to 8. Thereafter, BMP5 expression was restricted to the myocardium of the atrioventricular (AV) canal and outflow tract (OT) regions, where the valvuloseptal endocardial cushion tissue is induced. These results suggest that BMP5 may play important roles not only in myocardial differentiation, but also in the formation and maintenance of endocardial cushion tissue.

Cytokine induction by LVAD in the canine kidney

BACKGROUND

The outcome of left ventricular assist device (LVAD) support is reported to be associated with proinflammatory cytokines. We investigated the effect of LVAD support on renal function and the resultant cytokine induction.

METHODS

A prospective experimental study was performed using 15 mongrel dogs weighing 14 to 36 kg. LVAD was introduced in nine dogs (LVAD group) and the remaining six dogs were managed without LVAD support (control group). All animals were observed for six hours after thoracotomy. Renal regional blood flow was measured, and albumin-creatinine ratio (ACR) and N-acetyl-beta-D-glucoseaminidase index (NAGI) were evaluated as parameters of glomerular and tubular function, respectively. Tumor necrosis factor alpha (TNF-alpha) concentrations in the blood and homogenate of renal tissues were measured and immunohistological examination of renal tissues was conducted by means of anti-nuclear factor kappa B (NF-kappa B), TNF-alpha and interleukin 1 beta (IL- 1 beta) antibodies.

RESULTS

In the LVAD group, the renal cortex-medullar blood flow ratio significantly (p<0.05) decreased, and ACR was significantly (p<0.05) higher than in the control group, indicating glomerular insufficiency. There were no significant differences in NAGI and TNF-alpha levels in the blood and renal tissues between the two groups. Immunohistological examination of renal tissues demonstrated an accumulation of NF-kappa B, TNF-alpha, and IL-1 beta in the LVAD group.

CONCLUSIONS

An LVAD alters renal regional blood flow and induces a small amount of cytokines. We speculate that if an LVAD is introduced during systemic inflammatory response syndrome, the LVAD will induce a second attack resulting in multiorgan failure. For successful LVAD support, the appropriate selection of time periods is essential.

[Trust and cooperation: an experimental study of PD with choice of dependence]

This study examined the relationship between cooperation and trust in interpersonal trust formation. Previous studies of trust and cooperation using prisoner's dilemma (PD) games failed, methodologically as well as conceptually, to distinguish the former from the latter. In response to the criticism on the use of iterated PD games, and for the purpose of investigating dynamic relationship between trust and cooperation, an improvement in research methodology was recently proposed: namely, PD with choice of dependence (PD/D; Kakiuchi & Yamagishi, 1997; Yamagishi & Kakiuchi, 2000). We conducted an experiment to compare formation of trust relations in PD and PD/D. Result indicated a higher level of cooperation in PD/D than in PD. Further analysis of strategies used to build trustful relationship, where two partners trusted each other and reciprocated the other's trusting behavior, revealed that participants in PD/D adopted "cautious and unconditional cooperation strategy" rather than TFT strategy.

Troglitazone improves endothelial function and augments renal klotho mRNA expression in Otsuka Long-Evans Tokushima Fatty (OLETF) rats with multiple atherogenic risk factors

Targeted disruption of the klotho gene induces multiple phenotypes characteristic of human aging, including arteriosclerosis, pulmonary emphysema and osteoporosis. Moreover, we previously observed that insufficient klotho expression in mice leads to endothelial dysfunction. In the present study, we used Otsuka Long-Evans Tokushima Fatty (OLETF) rats, which exhibit hypertension, obesity, severe hyperglycemia and hypertriglyceridemia, and are thus considered an animal model of atherogenic disease, to test the effects of oral administration of troglitazone (200 mg/kg) on renal klotho mRNA expression and endothelial function. Systolic blood pressure, body weight, plasma glucose and triglyceride levels were all significantly higher in 30-week-old OLETF rats than in controls (LETO; Long-Evans Tokushima Otsuka) (p<0.05, n=7). In addition, endothelium-dependent relaxation of the aorta in response to 10(-5) M acetylcholine was significantly attenuated in OLETF rats (p<0.05, n=7), as was renal expression of klotho mRNA. Administration of troglitazone for 10 weeks significantly reduced systolic blood pressure, plasma glucose and triglyceride levels in OLETF rats, while augmenting endothelium-dependent aortic relaxation and renal klotho mRNA expression. These findings suggest that troglitazone protects the vascular endothelium against damage caused by the presence of multiple atherogenic factors.

Intraoperative identification of regenerated chorda tympani nerve and its relationship to recovered taste function

This study demonstrated a simple method of repairing the severed chorda tympani nerve and a method of intraoperative identification of regenerated nerves, and evaluated taste function of regenerated nerves. Seven patients who underwent staged tympanoplasty and whose chorda tympani nerve was severed during primary surgery were evaluated. When the chorda tympani nerve was severed during primary surgery, proximal and distal stumps were anastomosed or approximated almost in the original position and fixed with fibrin glue on the temporal muscle fascia used to reconstruct the eardrum by the underlay method. During primary surgery, end-to-end anastomosis was possible in 3 patients but nerve gap defects remained in the other 4 patients. In all 7 patients, regenerated nerves were identified during secondary surgery not in the tympanic cavity but in the submucosal layer of the previously reconstructed eardrum. In all patients, complete or incomplete recovery of taste perception was observed by both the filter paper disk method and electrogustometry, suggesting that the regenerated nerves had actual taste function. From these results, it was concluded that the severed chorda tympani nerve could regenerate in the reconstructed eardrum even if nerve gap defects remained between the proximal and distal cut ends, when repair or approximation of the nerve was properly completed.

Long-term follow-up results of electrogustometry and subjective taste disorder after middle ear surgery

OBJECTIVES

The present study compares the long-term follow-up results of electrogustometry with patient reports of taste dysfunction after middle ear surgery.

STUDY DESIGN

Retrospective review of 371 patients who underwent middle ear surgery.

METHODS

Patients were divided into the following groups depending on the degree of manipulation or surgical damage to the chorda tympani nerves: the no-touch group (group 1 [n = 109]); the touch group (group 2 [n = 149]); and the severed nerve group (group 3 [n = 113]). Electrogustometry was periodically performed over the course of several years.

RESULTS

The incidences of postoperative subjective taste disorder in groups 1, 2, and 3 were 2.8%, 25.5%, and 38.9%, respectively. Although the subjective taste disorder usually recovered within 1 to 2 years after surgery in all groups, it persisted for more than 2 years in 2.7% of the touch group and 5.3% of the severed nerve group. Concerning postoperative electrogustometric results, in the no-touch group, 8.3% of patients showed threshold elevation on electrogustometry, but the elevated thresholds completely recovered in all cases. In the touch group, 45% of patients exhibited elevated electrogustometric thresholds on their first postoperative test, including 32.9% who subsequently had complete electrogustometric recovery, 10.1% who subsequently had incomplete recovery, and 2% who failed to recover during the follow-up period. In the severed nerve group, none of the patients was responsive to the electrical stimulus on the first postoperative test, including 8.8% of patients who subsequently exhibited complete electrogustometric recovery, 32.7% who later had incomplete electrogustometric recovery, and 58.4% who never recovered any electrogustometric responsiveness. Nerve repair in the severed nerve group produced better recovery, as measured electrically.

CONCLUSIONS

The incidence of postoperative subjective taste disorder was low, although inconsistent with the high incidence of threshold elevation on electrogustometry, especially in the severed nerve group. Preservation or repair of the chorda tympani nerve is recommended in order to maintain or recover gustatory function.

Treatment of A-pattern esotropia with marked mongoloid slanting palpebral fissures

BACKGROUND

The association of oblique palpebral fissures and A- or V-pattern has not been clarified. We report two cases of A-pattern esotropia with marked mongoloid slanting palpebral fissures associated with vertical displacement of the horizontal rectus muscle.

CASES

Case 1 was a boy with Prader-Willi syndrome. He showed A-pattern esotropia with upward slanting palpebral fissures. Severe superior oblique muscle overaction was observed. Case 2 was a girl with meningocele. She also showed A-pattern esotropia with upward slanting palpebral fissures.

OBSERVATIONS

In case 1, weakening surgery of the superior oblique muscles did not improve the A-pattern. Coronal images of computed tomography showed one-half-muscle-width upward displacement of both lateral rectus muscles. After downward transposition surgery of the lateral rectus muscles, the preoperative A-pattern of 25 prism diopters (PD) was successfully corrected to 10 PD. In case 2 also, upward displacement of both lateral rectus muscles was shown by computed tomography. The preoperative A-pattern of 26 PD was corrected to 4 PD postoperatively after upward transposition surgery of the medial rectus muscles.

CONCLUSIONS

The vertical displacement of horizontal rectus muscles was considered the principal cause of A-pattern in these cases associated with marked mongoloid slanting palpebral fissures.

Multiplanar reconstruction MR image of primary adenoid cystic carcinoma of the central airway: (MPR of central airway adenoid cystic carcinoma)

Multiplanar reconstruction (MPR) is a method that allows free selection of computerized reconstruction images. We reviewed a total of six MPR magnetic resonance (MR) examinations in five cases of adenoid cystic carcinoma of the central airway, which is a rare low-grade malignant tumor. MPR MR provides images either longitudinally or at right angles to the longitudinal axis of the trachea and main bronchi, so it was useful to diagnose tumor extent along airways more precisely and to evaluate therapeutic effects. MPR MR may help in planning therapeutic strategy and in posttherapeutic follow-up.

Simultaneous removal of phenol and ammonia by an activated sludge process with cross-flow filtration

Attempts were made for removing ammonia from synthetic wastewater under the presence of phenol, which is inhibitory to nitrification, by using a single-stage activated sludge process with cross-flow filtration. Activated sludge biomass which had been acclimated with phenol for over 15 years was used for the inoculum, and synthetic wastewater was continuously supplied to the process retaining biomass at 8000 mg VSS l(-1). Phenol was completely removed, and ammonia was simultaneously nitrified to nitrate; nitrification rate reached 200 mg N l(-1) d(-1) when phenol was removed at a rate up to 300 mg l(-1) d(-1). It was observed that 0-13% of the ammonia was removed via denitrification. Intermittent aeration enhanced the denitrification rate to 160 mg N l(-1) d(-1) by utilizing phenol. and approximately 24% of the denitrified nitrogen was recovered as nitrous oxide. Methanol, which is the most commonly used electron donor in conventional nitrogen removal processes, did not enhance the denitrification rate of the phenol-acclimated activated sludge used in this study, however phenol did. The results suggest that this process potentially works as a space- and energy-saving nitrogen removal process by utilizing substances inhibitory to nitrifiers as electron donors for denitrification.