Molecular identification and antibiotic resistant bacteria isolated from primary dentition infections

BACKGROUND

Bacterial resistance to antibiotics is a health problem in many parts of the world. The aim of this study was to identify bacteria from dental infections and determine bacterial resistance to antibiotics used in dental care in the primary dentition.

METHODS

This cross-sectional study comprised 60 children who presented for dental treatment for active dental infections in the primary dentition. Samples from dental infections were collected and bacteria were identified by polymerase chain reaction (PCR) assay. Bacterial resistance to antibiotics was determined by colony forming units on agar plates containing amoxicillin, clindamycin and amoxillicin-clavulanic acid (A-CA) tested at 8 μg/ml or 16 μg/ml.

RESULTS

Clindamycin in both concentrations tested (8 μg/ml and 16 μg/ml) showed the highest bacterial resistance (85.9%), followed by amoxicillin (43.7%) and A-CA (12.0%). All comparisons among the three antibiotics used in the study exhibited statistical significance (p = <0.05) in both concentrations tested (8 μg/ml and 16 μg/ml), and under aerobic and anaerobic conditions. The most prevalent resistant species identified by PCR in primary dentition infections were: Streptococcus oralis and Prevotella intermedia (75.0%); Treponema denticola and Porphyromonas gingivalis (48.3%); Streptococcus mutans (45.0%); Campylobacter rectus; and Streptococcus salivarius (40%).

CONCLUSIONS

This study demonstrated that A-CA exhibited the lowest bacterial resistance for clinical isolates in primary dentition infections.

Rigorous patient-prosthesis matching of Perimount Magna aortic bioprosthesis

Background

Severe patient-prosthesis mismatch, defined as effective orifice area index ≤0.65 cm2 m−2, has demonstrated poor long-term survival after aortic valve replacement. Reported rates of severe mismatch involving the Perimount Magna aortic bioprosthesis range from 4% to 20% in patients with a small annulus.

Methods

Between June 2008 and August 2011, 251 patients (mean age 70.5 ± 10.2 years; mean body surface area 1.55 ± 0.19 m2) underwent aortic valve replacement with a Perimount Magna bioprosthesis, with or without concomitant procedures. We performed our procedure with rigorous patient-prosthesis matching to implant a valve appropriately sized to each patient, and carried out annular enlargement when a 19-mm valve did not fit. The bioprosthetic performance was evaluated by transthoracic echocardiography predischarge and at 1 and 2 years after surgery.

Results

Overall hospital mortality was 1.6%. Only 5 (2.0%) patients required annular enlargement. The mean follow-up period was 19.1 ± 10.7 months with a 98.4% completion rate. Predischarge data showed a mean effective orifice area index of 1.21 ± 0.20 cm2 m−2. Moderate mismatch, defined as effective orifice area index ≤0.85 cm2 m−2, developed in 4 (1.6%) patients. None developed severe mismatch. Data at 1 and 2 years showed only two cases of moderate mismatch; neither was severe.

Conclusions

Rigorous patient-prosthesis matching maximized the performance of the Perimount Magna, and no severe mismatch resulted in this Japanese population of aortic valve replacement patients.

Successful treatment of a rare case of neonatal Ebstein anomaly in a very low-birth-weight premature neonate

We report a successfully treated rare case of neonatal Ebstein anomaly in a low-birth-weight infant.

Histological difference between pulsed wave laser and continuous wave laser in endovenous laser ablation

BACKGROUND

Endovenous laser ablation to saphenous veins has been popular as a minimally invasive treatment for chronic venous insufficiency. However, adverse effects after endovenous laser ablation using continuous wave laser still remain. Pulsed wave with enough short pulse duration and sufficiently long thermal relaxation time may avoid the excess energy delivery, which leads to the perforation of the vein wall.

METHOD

(1) Free radiation: Laser is radiated in blood for 10 s. (2) Endovenous laser ablation: Veins were filled with blood and placed in saline. Endovenous laser ablations were performed.

RESULTS

(1) There were clots on the fiber tips with continuous wave laser while no clots with pulsed wave laser. (2) In 980-nm continuous wave, four of 15 specimens had ulcers and 11 of 15 had perforation. In 1470-nm continuous wave with 120 J/cm of linear endovenous energy density, two of three presented ulcers and one of three showed perforation. In 1470-nm continuous wave with 60 J/cm of linear endovenous energy density, two of four had ulcers and two of four had perforation. In 1320-nm pulsed wave, there were neither ulcers nor perforation in the specimens.

CONCLUSIONS

While endovenous laser ablation using continuous wave results in perforation in many cases, pulsed wave does not lead to perforation.

Genetic characteristics and pathogenic mechanisms of periodontal pathogens

Periodontal disease is caused by a group of bacteria that utilize a variety of strategies and molecular mechanisms to evade or overcome host defenses. Recent research has uncovered new evidence illuminating interesting aspects of the virulence of these bacteria and their genomic variability. This paper summarizes some of the strategies utilized by the major species - Aggregatibacter actinomycetemcomitans, Tannerella forsythia, Treponema denticola, and Porphyromonas gingivalis - implicated in the pathogenesis of periodontal disease. Whole-genome sequencing of 14 diverse A. actinomycetemcomitans strains has revealed variations in their genetic content (ranging between 0.4% and 19.5%) and organization. Strikingly, isolates from human periodontal sites showed no genomic changes during persistent colonization. T. forsythia manipulates the cytokine responses of macrophages and monocytes through its surface glycosylation. Studies have revealed that bacterial surface-expressed O-linked glycans modulate T-cell responses during periodontal inflammation. Periodontal pathogens belonging to the "red complex" consortium express neuraminidases, which enables them to scavenge sialic acid from host glycoconjugates. Analysis of recent data has demonstrated that the cleaved sialic acid acts as an important nutrient for bacterial growth and a molecule for the decoration of bacteria surfaces to help evade the host immune attack. In addition, bacterial entry into host cells is also an important prerequisite for the lifestyle of periodontal pathogens such as P. gingivalis. Studies have shown that, after its entry into the cell, this bacterium uses multiple sorting pathways destined for autophagy, lysosomes, or recycling pathways. In addition, P. gingivalis releases outer membrane vesicles which enter cells via endocytosis and cause cellular functional impairment.

Erythritol alters microstructure and metabolomic profiles of biofilm composed of Streptococcus gordonii and Porphyromonas gingivalis

The effects of sugar alcohols such as erythritol, xylitol, and sorbitol on periodontopathic biofilm are poorly understood, though they have often been reported to be non-cariogenic sweeteners. In the present study, we evaluated the efficacy of sugar alcohols for inhibiting periodontopathic biofilm formation using a heterotypic biofilm model composed of an oral inhabitant Streptococcus gordonii and a periodontal pathogen Porphyromonas gingivalis. Confocal microscopic observations showed that the most effective reagent to reduce P. gingivalis accumulation onto an S. gordonii substratum was erythritol, as compared with xylitol and sorbitol. In addition, erythritol moderately suppressed S. gordonii monotypic biofilm formation. To examine the inhibitory effects of erythritol, we analyzed the metabolomic profiles of erythritol-treated P. gingivalis and S. gordonii cells. Metabolome analyses using capillary electrophoresis time-of-flight mass spectrometry revealed that a number of nucleic intermediates and constituents of the extracellular matrix, such as nucleotide sugars, were decreased by erythritol in a dose-dependent manner. Next, comparative analyses of metabolites of erythritol- and sorbitol-treated cells were performed using both organisms to determine the erythritol-specific effects. In P. gingivalis, all detected dipeptides, including Glu-Glu, Ser-Glu, Tyr-Glu, Ala-Ala and Thr-Asp, were significantly decreased by erythritol, whereas they tended to be increased by sorbitol. Meanwhile, sorbitol promoted trehalose 6-phosphate accumulation in S. gordonii cells. These results suggest that erythritol has inhibitory effects on dual species biofilm development via several pathways, including suppression of growth resulting from DNA and RNA depletion, attenuated extracellular matrix production, and alterations of dipeptide acquisition and amino acid metabolism.

[Re-do coronary artery bypass grafting]

Redo-coronary artery bypass grafting( redo-CABG) still remains a challenging operation and is associated with a significantly higher risk of morbidity and mortality when compared with primary CABG. The higher risk of redo-CABG is largely attributable to the increased technical difficulty and the greater incremental risk in redo-CABG patients. Annual reports by the Japanese Association for Thoracic Surgery in recent years reveled that the absolute and relative number of redo-CABG gradually decreased, and in-hospital mortality did not change significantly over this periods and was much higher than primary CABG. The increasing use of percutaneous coronary intervention (PCI) for previous CABG patients could be a reason for the decrease of redo-CABG, and therefore surgery of redo-CABG is becoming more limited. This paper presents the current indications, safe surgical technique, and perioperative management of redo-CABG patients, as well as the contemporary results of redo-CABG in our institution.

Use of pacemaker programmers for disaster victim identification

Disaster victim identification (DVI) presents a number of physical and legal challenges, involving the degeneration of human remains and legal obstacles to forensic examinations. One non-invasive method for positive identification may be the use of a pacemaker programmer to detect and obtain data from pacemakers recovered from unidentified remains. To test the usefulness of this method, this investigation examined the efficiency and utility of 5 different pacemaker programmers in the positive identification of victims of the March 2011 tsunami in Japan at 8 disaster sites in May 2011. On scanning 148 sets of remains, data were successfully obtained from 1 implant in 1 set of remains, allowing for the rapid positive identification of the individual. Scanning pacemakers with pacemaker programmers can be a non-invasive method of positive identification that meets Japanese legal and institutional requirements, but this method is ineffective without a preceding whole-body X-ray scan.

Safety advantage of modified minimally invasive cardiac surgery for pediatric patients

Minimally invasive cardiac surgery (MICS) using a small surgical incision in children provides less physical stress. However, concern about safety due to the small surgical field has been noted. Recently, the authors developed a modified MICS procedure to extend the surgical field. This report assesses the safety and benefit of this modified procedure by comparing three procedures: the modified MICS (group A), conventional MICS (group B), and traditional open heart surgery (group C). A retrospective analysis was performed with 111 pediatric patients (age, 0-9 years; weight, 5-30 kg) who underwent cardiac surgery for simple cardiac anomaly during the period 1996-2010 at Juntendo University Hospital. The modified MICS method to extend the surgical view has been performed since 2004. A skin incision within 5 cm was made below the nipple line, and the surgical field was easily moved by pulling up or down using a suture or a hemostat. The results showed no differences in terms of gender, age, weight, or aortic cross-clamp time among the groups. Analysis of variance (ANOVA) indicated significant differences in mean time before cardiopulmonary bypass (CPB), CPB time, operation time, and bleeding. According to the indices, modified MICS was similar to traditional open surgery and shorter time or lower bleeding volume than conventional MICS. No major mortality or morbidity occurred. In conclusion, the modified MICS procedure, which requires no special techniques, was as safe as conventional open heart surgery and even reduced perioperative morbidity.

Effect of cardiac rehabilitation on muscle mass, muscle strength, and exercise tolerance in diabetic patients after coronary artery bypass grafting

BACKGROUND

The effects of cardiac rehabilitation (CR) on muscle mass, muscle strength, and exercise tolerance in patients with diabetes mellitus (DM) who received CR after coronary artery bypass grafting (CABG) have not been fully elucidated.

METHODS

We enrolled 78 consecutive patients who completed a supervised CR for 6 months after CABG (DM group, n=37; non-DM group, n=41). We measured mid-upper arm muscle area (MAMA), handgrip power (HGP), muscle strength of the knee extensor (Ext) and flexor (Flex), and exercise tolerance at the beginning and end of CR.

RESULTS

No significant differences in confounding factors, including age, gender, ejection fraction, or number of CR sessions, were observed between the two groups. At the beginning of CR, the levels of Ext muscle strength and peak VO2 were significantly lower in the DM group than in the non-DM group. At the end of CR, significant improvement in the levels of muscle strength, HGP, and exercise tolerance was observed in both groups. However, the levels of Ext muscle strength, HGP, peak VO2, thigh circumference, and MAMA were significantly lower in the DM group than in the non-DM group. In addition, no significant improvement in thigh circumference and MAMA was observed in the DM group. At the end of CR, the levels of thigh circumference and MAMA correlated with Ext and Flex muscle strength as well as with HGP. Percent changes in the levels of Ext muscle strength were significantly correlated with those of MAMA and hemoglobin A1c.

CONCLUSIONS

These data suggest that improvement in muscle strength may be influenced by changes in muscle mass and high glucose levels in DM patients undergoing CR after CABG. A CR program, including muscle mass intervention and blood glucose control, may improve deterioration in exercise tolerance in DM patients after CABG.

Wavering calcified amorphous tumour of the heart in a haemodialysis patient

Calcified amorphous tumour is a rare, non-neoplastic, endocardially based, intracavitary cardiac mass. This report describes a 59-year old man in whom a mobile mass was found incidentally in the heart by routine echocardiography after he had been on haemodialysis for 3 years. Transoesophageal echocardiography revealed a high-echoic swinging tumour that originated from the annulus of the anterior commissure of the mitral valve. Surgical resection was performed to prevent embolization, and his clinical course was excellent.

Music exposure induced prolongation of cardiac allograft survival and generated regulatory CD4⁺ cells in mice

In clinical practice, music has been used to decrease stress, heart rate, and blood pressure and to provide a distraction from disease symptoms. We investigated sound effects on alloimmune responses in murine heart transplantation. Naïve and eardrum-ruptured CBA/N (CBA, H2(K)) underwent transplantation of a C57BL/6 (B6, H2(b)) heart and were exposed to 1 of 3 types of music-opera (La Traviata), classical (Mozart), and New Age (Enya)-or 1 of 6 different single sound frequencies for 7 days. An adoptive transfer study was performed to determine whether regulatory cells were generated in allograft recipients. Cell-proliferation, cytokine, and flow cytometry assessments were also performed. CBA recipients of a B6 graft exposed to opera and classical music had significantly prolonged allograft survival (median survival times [MSTs], 26.5 and 20 days, respectively), whereas those exposed to 6 single sound frequencies and New Age did not (MSTs, 7, 8, 9, 8, 8, 8, and 11 days, respectively). Untreated and eardrum-ruptured CBA rejected B6 grafts acutely (MSTs, 7 and 8.5 days, respectively). Adoptive transfer of whole splenocytes, CD4(+) cells, and CD4(+)CD25(+) cells from opera-exposed primary recipients resulted in significantly prolonged allograft survival in naive secondary recipients (MSTs, 36, 68, and >50 days, respectively). Cell-proliferation, interleukin (IL)-2 and interferon-γ were suppressed in opera-exposed mice, whereas IL-4 and IL-10 from opera-exposed recipients were up-regulated. Flow cytometry studies showed an increased CD4(+)CD25(+)Foxp3(+) cell population in splenocytes from opera-exposed mice. In conclusion, exposure to some types of music may induce prolonged survival of fully allogeneic cardiac allografts and generate CD4(+)CD25(+)Foxp3(+) regulatory cells.

Auditory stimulation of opera music induced prolongation of murine cardiac allograft survival and maintained generation of regulatory CD4+CD25+ cells

BACKGROUND

Interactions between the immune response and brain functions such as olfactory, auditory, and visual sensations are likely. This study investigated the effect of sounds on alloimmune responses in a murine model of cardiac allograft transplantation.

METHODS

Naïve CBA mice (H2k) underwent transplantation of a C57BL/6 (B6, H2b) heart and were exposed to one of three types of music--opera (La Traviata), classical (Mozart), and New Age (Enya)--or one of six different single sound frequencies, for 7 days. Additionally, we prepared two groups of CBA recipients with tympanic membrane perforation exposed to opera for 7 days and CBA recipients exposed to opera for 7 days before transplantation (pre-treatment). An adoptive transfer study was performed to determine whether regulatory cells were generated in allograft recipients. Immunohistochemical, cell-proliferation, cytokine, and flow cytometry assessments were also performed.

RESULTS

CBA recipients of a B6 cardiac graft that were exposed to opera music and Mozart had significantly prolonged allograft survival (median survival times [MSTs], 26.5 and 20 days, respectively), whereas those exposed to a single sound frequency (100, 500, 1000, 5000, 10,000, or 20,000 Hz) or Enya did not (MSTs, 7.5, 8, 9, 8, 7.5, 8.5 and 11 days, respectively). Untreated, CBA mice with tympanic membrane perforations and CBA recipients exposed to opera for 7 days before transplantation (pre-treatment) rejected B6 cardiac grafts acutely (MSTs, 7, 8 and 8 days, respectively). Adoptive transfer of whole splenocytes, CD4+ cells, or CD4+CD25+ cells from opera-exposed primary allograft recipients resulted in significantly prolonged allograft survival in naive secondary recipients (MSTs, 36, 68, and > 100 days, respectively). Proliferation of splenocytes, interleukin (IL)-2 and interferon (IFN)-γ production was suppressed in opera-exposed mice, and production of IL-4 and IL-10 from opera-exposed transplant recipients increased compared to that from splenocytes of untreated recipients. Flow cytometry studies showed an increased CD4+CD25+ Forkhead box P3 (Foxp3)+ cell population in splenocytes from those mice.

CONCLUSION

Our findings indicate that exposure to opera music, such as La traviata, could affect such aspects of the peripheral immune response as generation of regulatory CD4+CD25+ cells and up-regulation of anti-inflammatory cytokines, resulting in prolonged allograft survival.

Predictors of early and mid-term results in contemporary aortic valve replacement for aortic stenosis

BACKGROUND

The purpose of this study was to evaluate clinical risk factors and assess the impact of the Society of Thoracic Surgeons (STS) scores on outcomes after contemporary aortic valve replacement (AVR) for aortic stenosis (AS).

METHODS

We retrospectively analyzed the data from 209 consecutive patients with AS (mean 69 ± 9 years) who underwent AVR. The outcomes measured included operative mortality, postoperative complications, postoperative prolonged length of stay (PLOS), discharge to nonhome location, and mid-term mortality.

RESULTS

Operative mortality was 3.8%, and five-year survival was 88.6 ± 2.8%. Multivariable analysis revealed preoperative New York Heart Association (NYHA) class as a significant predictor of both operative mortality (p = 0.03; odds ratio [OR]: 8.5) and mid-term mortality (p = 0.02; OR: 10.5). NYHA class also emerged as an independent predictor for postoperative complications (p = 0.002; OR: 5.8) and PLOS (p = 0.01; OR: 2.5). Other preoperative independent predictors included dialysis for PLOS (p = 0.04; OR: 2.9), age (p = 0.03; OR: 1.1), and left ventricular ejection fraction (EF; p = 0.03; OR: 0.9) for nonhome discharge, and EF for mid-term mortality (p = 0.01; OR: 0.9). The mean STS-PROM (predicted risk of mortality) was 4.6% ± 6.1%, and thus, the observed-to-expected (O/E) ratio of operative mortality in our series was 0.82.

CONCLUSIONS

Advanced NYHA class, older age, dialysis, and lower EF are significant independent preoperative risk factors for early and mid-term results of AVR for AS. Consideration of these predictors should be used to identify high-risk patients requiring AVR for AS.

Propensity score analysis of 10-year long-term outcome after bypass surgery or plain old balloon angioplasty in patients with metabolic syndrome

Clinical hard outcomes (death and myocardial infarction) between bypass surgery (CABG) and percutaneous coronary intervention (PCI) are generally similar, whereas target vessel revascularization and angina relief are often superior with CABG. However, there are no data regarding 10-year long-term clinical outcomes between the two procedures in metabolic syndrome (MetS). The aim of this study was to assess the long-term outcomes of CABG and plain old balloon angioplasty (POBA) in MetS patients. We enrolled 869 patients, 318 (36.6%) and 551 (63.4%) of whom underwent POBA and CABG, respectively. During follow-up (10.1 ± 3.5 years), 221 patients died (118 cardiovascular deaths) and 256 underwent revascularization. We predicted the probability of undergoing CABG using propensity analysis. Unadjusted survival was significantly lower in the CABG group because of unfavorable baseline characteristics. After adjusting for baseline variables including propensity score, POBA and CABG did not differ in terms of all cause (hazard ratio [HR] of CABG, 1.46; P = 0.132) and cardiovascular mortality (HR of CABG, 1.11; P = 0.757). However, the risk of subsequent revascularization was significantly lower in the CABG group than in the POBA group (HR of CABG, 0.15; P < 0.001). This study demonstrated that CABG is superior to POBA in terms of target vessel revascularization in MetS patients, whereas there were no significant differences in mortality after adjusting for baseline variables including propensity score.

Danazol induces prolonged survival of fully allogeneic cardiac grafts and maintains the generation of regulatory CD4(+) cells in mice

Danazol, a derivative of testosterone, is useful for treatment of endometriosis as well as pretreatment for in vitro fertilization and embryo transfer, although its mechanisms of action are unclear. The aim of this study was to investigate the effect of danazol on alloimmune responses in murine heart transplantation. CBA male mice (H2(k) ) underwent transplantation of C57BL/6 male (H2(b) ) hearts and received a single dose of danazol (0.4, 1.2 or 4mg/kg/day) by intraperitoneal injection on the day of transplantation and for 6days thereafter. An adoptive transfer study was performed to determine whether regulatory cells were generated. The median survival time (MST) of allografts in danazol-treated (1.2 and 4mg/kg/day) mice was 28 and 63days, respectively, compared with 7days in untreated mice. Moreover, secondary CBA recipients given whole splenocytes or CD4(+) cells from primary danazol-treated (4mg/kg/day) CBA recipients 30days after transplantation had prolonged allograft survival (MSTs, 29 and 60days, respectively). Cell proliferation, interleukin (IL)-2 and interferon-γ were suppressed in danazol-treated mice, whereas IL-4 and IL-10 were up-regulated. Moreover, danazol directly suppressed allo-proliferation in a mixed leukocyte culture. Flow cytometry showed an increased CD4(+) CD25(+) Foxp3(+) cell population in splenocytes from danazol-treated mice. Danazol prolongs cardiac allograft survival and generates regulatory CD4(+) cells.

Non-high-density lipoprotein cholesterol is a practical predictor of long-term cardiac death after coronary artery bypass grafting

BACKGROUND

Recent studies have demonstrated that non-high-density lipoprotein cholesterol (non-HDL-C) can predict the risk of cardiovascular events among general population without coronary heart disease (CHD). However, few studies have investigated the predictive value of non-HDL-C for long-term prognosis in patients with CHD. The purpose of this study was to investigate whether non-HDL-C can predict long-term cardiovascular events in patients with CHD who underwent coronary artery bypass grafting (CABG).

METHODS

We enrolled 1074 consecutive patients who underwent CABG at Juntendo University Hospital between 1984 and 1994, and obtained mortality data through 2000. We divided the patients into 2 groups by the median non-HDL-C level at baseline (180 mg/dL) and used Kaplan-Meier method with log-rank test for survival analyses. Cox proportional-hazard regression model was used to calculate the relative risk (RR) of cardiac death.

RESULTS

The mean follow-up period was 10.6±3.5 years. The survival rate of cardiac death was significantly lower in the high non-HDL-C group than that in the low non-HDL-C group (log-rank test; p=0.006). Furthermore, in proportional regression analysis adjusted for conventional coronary risk factors, metabolic syndrome, statin treatment, and use of artery bypass graft, the increased levels of non-HDL-C were significant and independent predictor of cardiac death beyond other lipid parameters (RR1.22; by 10 mg/dL non-HDL-C increasing, 95% confidence interval 1.03-1.44; p<0.05).

CONCLUSIONS

The increased levels of non-HDL-C were significantly associated with an increased risk of cardiac death. Baseline non-HDL-C levels may be a practical predictor of long-term cardiac death in patients with CHD after CABG.

Mid-term results for the Maze procedure in patients with non-mitral valvular atrial fibrillation

BACKGROUND

The Maze procedure in patients without mitral valve disease remains controversial, because of the increased invasiveness and operation time required to create additional incisions in the atria. The aim of this study was to assess prognosis following the Maze procedure in patients without mitral valve disease.

METHODS AND RESULTS

One hundred and seven consecutive patients who underwent the Maze procedure between 2002 and 2008 was enrolled in this study. Patients were divided into two groups based on the presence or absence of mitral valve disease. Freedom from atrial fibrillation was compared by multivariate logistic regression analysis at discharge. The Kaplan-Meier method and Cox-proportional hazard analysis adjusted for other predictors were estimated to compare freedom from atrial fibrillation at follow-up. Follow-up was 98% complete and mean duration of follow-up was 457 days. Operation and aorta cross-clamp times were similar between groups. No differences were identified in freedom from atrial fibrillation at discharge (non-mitral valve surgery, 55% vs. mitral valve surgery, 66%) or follow-up (57% vs. 61%, respectively). In multivariate Cox proportional hazard modelling, the presence of mitral valve disease was not associated with a poor success rate of conversion.

CONCLUSIONS

Results of the Maze procedure for atrial fibrillation without mitral valve disease were acceptable. The Maze procedure could be a beneficial option for these patients to avoid adverse events of atrial fibrillation.

Association of low glomerular filtration rate with the incidence of stroke in patients following complete coronary revascularization

BACKGROUND

Low glomerular filtration rate (GFR) is associated with a worse outcome after coronary revascularization. Recently, a new specific equation to calculate the estimated GFR (eGFR) in Japanese populations has been reported, and it might be more accurate than the previously used equations. However, the relationship between a low GFR defined using the new equation for the Japanese population and the incidence of stroke following complete coronary revascularization is not yet known.

METHODS AND RESULTS

Consecutive patients who underwent complete coronary revascularization (percutaneous coronary intervention and bypass surgery) between 1984 and 1992 were enrolled. Patients on dialysis were excluded. Enrolled patients were divided into 2 groups: the preserved GFR group and the low GFR group. Low GFR was defined as eGFR<60 ml·min⁻¹·1.73 m⁻². The incidence of fatal and non-fatal stroke was compared between the groups. Among the 1,809 patients that were enrolled, 321 were placed in the low GFR group. During follow up (mean, 11.4 [2.9] years), there were 127 (7.0%) stroke events. Multivariable analysis using a Cox proportional hazards regression model revealed that the incidence of stroke was significantly higher in the low GFR group than in the preserved GFR group (hazard ratio, 1.66; 95% confidence interval, 1.10-2.48; P = 0.008).

CONCLUSIONS

Low GFR, defined as eGFR <60 ml·min⁻¹·1.73 m⁻², using a new specific equation for the Japanese population was associated with an increased risk of fatal and non-fatal stroke over a 10-year period after complete coronary revascularization.

Impact of diabetes on muscle mass, muscle strength, and exercise tolerance in patients after coronary artery bypass grafting

BACKGROUND

The impact of diabetes mellitus (DM) on muscle mass, muscle strength, and exercise tolerance in patients who had undergone coronary artery bypass grafting (CABG) has not been fully elucidated.

METHODS

We enrolled 329 consecutive patients who received cardiac rehabilitation (CR) after CABG (DM group, n=178; non-DM group, n=151) and measured lean body weight, mid-upper arm muscle area (MAMA), and handgrip power (HGP) at the beginning of CR. We also performed an isokinetic strength test of the knee extensor (Ext) and flexor (Flex) muscles and a cardiopulmonary exercise testing at the same time.

RESULTS

No significant differences in risk factors, including age, gender, number of diseased vessels, or ejection fraction were observed between the 2 groups. The levels of Ext muscle strength, peak oxygen uptake, and anaerobic threshold were significantly lower in the DM group than in the non-DM group (all p<0.05). Both peak oxygen uptake and MAMA correlated with Ext and Flex muscle strength as well as HGP (all p<0.005). The MAMA, HGP, and Ext muscle strength were lower in patients who received insulin therapy than in those who did not. Interestingly, fasting glucose levels significantly and negatively correlated with Ext muscle strength.

CONCLUSIONS

These data suggest that DM patients had a lower muscle strength and exercise tolerance than non-DM patients. Moreover, a high glucose level may affect these deteriorations in DM patients after CABG.

Inhibition of connexin43 dephosphorylation is involved in protective effects of diltiazem on cardiac function during hypoxic injury

BACKGROUND

Connexin43 (Cx43), a gap junction protein, mediates cell-cell communication via electrical and chemical coupling. Ischemic stress of the cardiac muscle interrupts intercellular communication by changing the distribution and phosphorylation status of Cx43. This may be a factor contributing to reentrant arrhythmia. The calcium channel blocker diltiazem is known for its protective and anti-arrhythmogenic effect in ischemic heart disease. In this study, we assess the effect of diltiazem pretreatment upon ischemia-induced phosphorylation change of Cx43.

METHODS

Langendorff preparations of isolated Wistar rat hearts were performed. After stabilization, hearts were treated with (D+) or without diltiazem (D⁻), then subjected to hypoxia-reoxygenation. After perfusion, the left ventricle was prepared for immunocytochemistry and immunoblot analysis.

RESULTS

During perfusion, left ventricular function was better in the D+ group than the D⁻ group. Immunostaining of the heart indicated that dephosphorylated Cx43 (dpCx43) signal was increased after hypoxic perfusion, and this finding was confirmed by immunoblot data. The quantitative area analysis of dpCx43 using the immunohistochemical approach showed that the dpCx43-positive area was enlarged, as the hypoxic perfusion time was longer, and it was reduced by pretreatment of diltiazem. There was a negative correlation between the dpCx43 area and %RPP (rate-pressure product), calculated by heart rate and contraction force.

CONCLUSIONS

Pretreatment of diltiazem could protect the heart against hypoxia-reoxygenation injury by attenuation of dephosphorylation of Cx43. The anti-arrhythmic mechanism of diltiazem may include the preservation of phosphorylation status of Cx43 after hypoxia-reoxygenation injury.

Cognitive status correlates with white matter alteration in Parkinson's disease

Patients with Parkinson's disease (PD) can develop mild cognitive impairment (PD-MCI), frequently progressing to dementia (PDD). Here, we aimed to elucidate the relationship between white matter alteration and cognitive status in PD and dementia with Lewy bodies (DLB) by using diffusion tensor imaging. We also compared the progression patterns of white and gray matter and the cerebral perfusion. We enrolled patients with PD cognitively normal (PD-CogNL, n = 32), PD-MCI (n = 28), PDD (n = 25), DLB (n = 29), and age- and sex-matched healthy control subjects (n = 40). Fractional anisotropy (FA) map of a patient group was compared with that of control subjects by using tract-based spatial statistics. For the patient cohort, intersubject voxel-wise correlation was performed between FA values and Mini-Mental Status Examination (MMSE) scores. We also evaluated the gray matter and the cerebral perfusion by conducting a voxel-based analysis. There were significantly decreased FA values in many major tracts in patients with PD-MCI, PDD, and DLB, but not in PD-CogNL, compared with control subjects. FA values in the certain white matter areas, particularly the bilateral parietal white matter, were significantly correlated with MMSE scores in patients with PD. Patients with PDD and DLB had diffuse gray matter atrophy. All patient groups had occipital and posterior parietal hypoperfusion when compared with control subjects. Our results suggest that white matter damage underlies cognitive impairment in PD, and cognitive impairment in PD progresses with functional alteration (hypoperfusion) followed by structural alterations in which white matter alteration precedes gray matter atrophy.

String-sign in left internal thoracic artery is associated with regression in left main trunk stenosis after coronary artery bypass

The left internal thoracic artery (LITA) is the conduit of choice for coronary artery bypass (CABG) due to favorable long-term patency. Uncommonly, diffuse narrowing like a string without significant stenosis of an anastomosis is observed in the LITA graft (called "string sign"). Isolated left main trunk (LMT) diseases were reported to regress in some cases. However, the relationship between "string sign" and the regression of solitary LMT disease remains unknown.We retrospectively studied 40 consecutive patients with isolated LMT stenosis who underwent CABG using LITA and who underwent angiography before and after operation (31 males, 9 females, mean age, 65.0 years). The patients were divided into 2 groups according to the postoperative angiographic outcomes of the LITA graft: one group included patients with "string sign" (6 patients), the other group consisted of patients with a patent LITA graft (34 patients).There were no significant differences in clinical backgrounds between the two groups. The 2 groups showed similar quantitative % coronary artery stenosis of the LMT before operation (77.5% versus 76.8%) and the observation period was similar in both groups. Coronary angiography after CABG revealed that % stenosis of the LMT in patients with "string sign" was significantly less than that in patients with a patent LITA graft (41.7 ± 26% versus 82.5 ± 11%, P < 0.001). Regression in LMT was significantly more frequently observed in the "string sign group". Furthermore, ostial stenosis was more frequent in patients with "string sign". "String phenomenon" of the LITA graft is one of the signs related to the regression of LMT stenosis, and especially in ostial stenosis of the LMT.

Reconsiderations of mitral stenosis: rheumatic mitral valve repair and the Wilkins score

BACKGROUND

Mitral valve repair is a feasible treatment option in patients with rheumatic mitral valve disease, but it is not always successful. Mitral valve replacement is generally the surgical treatment of choice in such patients. We aimed to examine whether the Wilkins score can predict the feasibility of surgical repair in such patients.

METHODS

Mitral valve surgery was performed on 14 patients by the same surgeon (A.A.). Five patients underwent mitral valve repair (group I), and nine patients underwent mitral valve replacement (group II). The Wilkins scores were determined by assessing echocardiography findings. The selection of mitral valve repair or replacement was based on the intraoperative findings and the preferences of the same surgeon (A.A.). In group I, we performed chordal reconstruction, augmentation of the posterior leaflet, resection of chordae, decalcification of the commissure, commissurotomy, slicing of the anterior leaflet, division of the papillary muscle, and ring annuloplasty in various combinations.

RESULTS

There were no significant differences between the two groups with regard to any component of the preoperative Wilkins score. There was no significant difference in the pre- and postoperative scores in group I; however, the mitral valve orifice area was significantly improved after the operation (pre- and postoperative mean values: 1.3 ± 0.3 and 2.0 ± 0.4, P < 0.05).

CONCLUSION

Mitral valve repair is effective in treating rheumatic mitral stenosis. However, the Wilkins score may not be useful in predicting the feasibility of mitral repair.