Efficacy and safety of atrial fibrillation ablation in heart failure patients with left ventricular ejection fraction less than 50.

INTRODUCTION: The efficacy of catheter ablation in patients with low cardiac function has been previously reported; however, only a few studies have included mid-range ejection fraction (mrEF). This study aimed to evaluate the efficacy and safety of atrial fibrillation (AF) ablation in patients with left ventricular ejection fraction (LVEF) < 50%. METHODS: This study retrospectively analyzed 79 patients (reduced ejection fraction [rEF]/mrEF, 38/41; paroxysmal/persistent, 37/42; heart failure hospitalizations within one year before ablation, 36 [45.6%]) who underwent the first ablation procedure at our hospital from April 2017 to December 2021. Radiofrequency ablation and cryoablation were performed for 69 and 10 patients, respectively. RESULTS: Complications included pacemaker implantation for postoperative sick sinus syndrome in one patient and inguinal hematoma in one patient. Regarding efficacy, there were significant postoperative improvements in echocardiographic data, blood test values, and diuretic use. After a mean follow-up of 60 months, 86.1% patients had no AF recurrence. There were 9 heart failure hospitalizations (11.4%) and 5 all-cause deaths (6.3%); no significant differences were found between the rEF and mrEF groups. No significant predictors of AF recurrence were found in preoperative patient characteristics. CONCLUSION: AF ablation in patients with LVEF <50% significantly improved cardiac and renal functions with few complications, resulting in a high non-recurrence rate and reduced heart failure.

Usefulness of P-wave duration in patients with sick sinus syndrome as a predictor of atrial fibrillation.

BACKGROUND: This study aimed to clarify P-wave duration (PWD) ability before pacemaker implantation to predict worsening atrial fibrillation (AF) burden after the procedure. METHODS: We retrospectively investigated 75 patients who underwent permanent pacemaker implantation due to sick sinus syndrome (SSS) at Komaki City Hospital between January 2006 and May 2019. Worsening AF burden was defined as an increase in the number of AF episodes, each lasting ≥5.5 hours a day. RESULTS: In the study population, 17 patients (23%) had worsening AF burden during the follow-up period. These patients had significantly longer PWD in lead Ⅱ (117.9 ± 19.9 ms vs 101.3 ± 20.0 ms, P = .002) than the patients without worsening AF burden. The best discriminative cutoff value for PWD in lead Ⅱ was 108 ms (sensitivity, 77%; specificity, 67%). In multivariate analysis, PWD in lead II ≥108 ms (hazard ratio, 5.395; 95% confidence interval, 1.352-21.523; P = .017) was an independent predictor of worsening AF burden. Patients with PWD in lead II <108 ms showed a significantly higher event-free rate against worsening AF burden than those with PWD in lead II ≥108 ms (81% vs 9%, P = .005). CONCLUSIONS: Prolonged PWD before pacemaker implantation was the most important independent predictor of worsening AF burden after the procedure. In patients with SSS, prolonged PWD can be a useful marker for predicting worsening of AF burden after pacemaker implantation.

Low temperature synthesis of barium oxynitridosilicates using BaCN2 and SiO2.

Barium oxynitridosilicates, Ba3Si6O12N2 and Ba3Si6O9N4, were obtained from a mixture of BaCN2 and SiO2 at 800 °C, which is several hundred degrees lower than the temperature required in solid state reactions using BaCO3, SiO2 and Si3N4. The low-temperature formation mechanism was investigated by thermogravimetry analysis in conjunction with gas chromatography and mass spectroscopy. The phase ratio between the oxynitridosilicates was controlled by tuning the reaction temperature, duration, and atmosphere. Almost single-phase Ba3Si6O12N2 was obtained by reaction at 800 °C for 15 h under a N2 atmosphere, but the product changed to Ba3Si6O9N4 after 50 h at 800 °C or by heating at 950 °C for 15 h. The photoluminescence properties of Eu-doped products obtained at 800 °C using a mixture of BaCN2 : Eu and SiO2 were investigated.

Amorphous High-Surface-Area Aluminum Hydroxide-Bicarbonates for Highly Efficient Methyl Orange Removal from Water.

Amorphous high-surface-area aluminum hydroxide-bicarbonates were synthesized starting from AlCl3, base, and bicarbonate in water. Composites with a chemical formulas of [Al13O4(µ-OH)24(H2O)6.5(OH)5.5](HCO3)1.5 (I-NaOH) and [Al13O4(µ-OH)24(H2O)6(OH)6](HCO3) (I-NH3) were obtained by the use of NaOH/NaHCO3 and NH3/NH4HCO3 as base/bicarbonate, respectively. The surface area of the composites was highly dependent on the pH level of the synthetic solution, and composites with high surface areas (ca. 200 m2 g-1) were obtained around pH 7-8. Pore-size distributions determined from the N2 adsorption isotherms showed that I-NH3 and I-NaOH possess mainly large (pore radius rp > 3 nm) and small (rp < 3 nm) pores, respectively, despite similar surface areas. While SEM images showed that both I-NH3 and I-NaOH were aggregates of nanoparticles, the particles were more fused in I-NaOH, which is in line with the existence of small pores and the use of a stronger base (NaOH), which would facilitate the dehydration condensation reaction. The composites were applied as adsorbents to remove methyl orange (MO) from water. The time course of MO adsorption was readily fitted with a pseudo-second-order model, and over 90% MO removal was attained within 10 min with I-NH3, while I-NaOH showed much less MO removal (26%). The MO adsorption isotherm of I-NH3 was reproduced with a Langmuir model with an adsorption capacity of 154 mg g-1. Notably, the aluminum hydroxide-bicarbonates could not absorb methylene blue, which is a cationic dye, while anions (MO and PO43-) were readily absorbed. Solid-state 27Al MAS NMR spectra showed that the concentration of 5-coordinated aluminum species, which may serve as guest binding sites, was higher for I-NH3. These results show that electrostatic interaction between anionic MO and coordinatively unsaturated 5-coordinated cationic aluminum species and the large external surface area of I-NH3 contribute to the highly efficient MO adsorption.

Reduced exercise capacity and clinical outcomes following acute myocardial infarction.

Reduced exercise capacity is known to be an important predictor of poor prognosis and disability in patients with cardiovascular diseases and chronic heart failure, and even members of the general population. However, data about exercise capacity assessed by cardiopulmonary exercise testing (CPX) in acute myocardial infarction (AMI) patients who underwent primary percutaneous coronary intervention (PCI) is scarce. Among 594 consecutive AMI patients who underwent primary PCI, we examined 136 patients (85.3% men, 64.9 ± 11.9 years) who underwent CPX during hospitalization for AMI. CPX was usually performed 5 days after the onset of AMI. Reduced exercise capacity was defined as peak VO2 ≤ 12. Clinical outcomes including all-cause death, myocardial infarction, and hospitalization due to heart failure were followed. Among 136 patients, reduced exercise capacity (peak VO2 ≤ 12) was seen in 38 patients (28%). Patients with reduced exercise capacity were older, more likely to have hypertension, and had lower renal function. In echocardiography, patients with reduced exercise capacity had higher E/e' and larger left atrial dimension. Multivariate logistic analysis showed that E/e' (OR 1.19, 95% CI 1.09-1.31, p < 0.001) was an independent predictor of reduced exercise capacity (peak VO2 ≤ 12). Median follow-up term was 12 months (IQR 9-22). The occurrence of composite endpoints of all-cause death, myocardial infarction, and hospitalization due to heart failure was significantly higher in patients with peak VO2 ≤ 12 than those with peak VO2 > 12 (p < 0.001). Reduced exercise capacity following primary PCI in AMI patients is associated with diastolic dysfunction and may lead to poorer clinical outcomes.

Comparison of the measurement properties of the Functional Independence and Difficulty Scale with the Barthel Index in community-dwelling elderly people in Japan.

BACKGROUND: The new Functional Independence and Difficulty Scale (FIDS) is a tool for assessing the performance of basic activities of daily living (BADL). Because many BADL measures already exist, it is important to know whether FIDS can offer added benefit over the existing measures. AIMS: This study compared measurement properties between the FIDS and a representative BADL assessment tool, the Barthel Index (BI). METHODS: Recruitment of the participants was done on the basis of convenience sampling. Participants were community-dwelling elderly Japanese subjects (n = 314; age ≥65 years) divided into a healthy elderly group [n = 225; subjects not using long-term care insurance (LTCI) services] and frail elderly group (n = 89; subjects using LTCI services). For each group, ceiling effect (percent participation with the maximum score) was calculated, and it was compared between the two scales. Associations between the FIDS, BI and Medical Outcomes Study Short Form 8 Health Survey (SF-8) were evaluated by Spearman correlation coefficient and partial correlations. Partial correlations coefficients to SF-8 were compared between the two scales. RESULTS: FIDS showed a relatively small ceiling effect compared to the BI. Compared to the BI, FIDS showed a significant positive partial correlation with the broader aspect of the SF-8 subscales, but the strength of correlation between FIDS and SF-8 was weak to negligible. CONCLUSIONS: The FIDS might be less affected by ceiling effect than the BI. Additional studies using a sufficient number of probability samples are needed to clarify whether FIDS has any benefit over BI in terms of correlations with the SF-8.

Developmentally-regulated excision of the SPß prophage reconstitutes a gene required for spore envelope maturation in Bacillus subtilis.

Temperate phages infect bacteria by injecting their DNA into bacterial cells, where it becomes incorporated into the host genome as a prophage. In the genome of Bacillus subtilis 168, an active prophage, SPß, is inserted into a polysaccharide synthesis gene, spsM. Here, we show that a rearrangement occurs during sporulation to reconstitute a functional composite spsM gene by precise excision of SPß from the chromosome. SPß excision requires a putative site-specific recombinase, SprA, and an accessory protein, SprB. A minimized SPß, where all the SPß genes were deleted, except sprA and sprB, retained the SPß excision activity during sporulation, demonstrating that sprA and sprB are necessary and sufficient for the excision. While expression of sprA was observed during vegetative growth, sprB was induced during sporulation and upon mitomycin C treatment, which triggers the phage lytic cycle. We also demonstrated that overexpression of sprB (but not of sprA) resulted in SPß prophage excision without triggering the lytic cycle. These results suggest that sprB is the factor that controls the timing of phage excision. Furthermore, we provide evidence that spsM is essential for the addition of polysaccharides to the spore envelope. The presence of polysaccharides on the spore surface renders the spore hydrophilic in water. This property may be beneficial in allowing spores to disperse in natural environments via water flow. A similar rearrangement occurs in Bacillus amyloliquefaciens FZB42, where a SPß-like element is excised during sporulation to reconstitute a polysaccharide synthesis gene, suggesting that this type of gene rearrangement is common in spore-forming bacteria because it can be spread by phage infection.

Clinical course of congenital nephrotic syndrome and Denys-Drash syndrome in Japan.

BACKGROUND: The prognosis of Japanese patients with congenital nephrotic syndrome (CNS) and Denys-Drash syndrome (DDS) is not clear. METHODS: Five patients with CNS and four patients with DDS, which causes secondary CNS, were studied retrospectively. RESULTS: Seven patients were sporadic and two DDS patients were identical twins. Five CNS patients presented with edema within 3 months of birth. In four DDS patients, edema was not noted and end-stage renal disease developed between 7 months and 6 years of age. Of these five CNS patients, one patient had cerebral thrombosis and cytomegalovirus pneumonia at the onset and another patient died during dialysis. Frequent intravenous albumin administration required, growth and development during infancy were varied. Of the nine patients with CNS and DDS, seven received renal transplantation and were alive with functioning grafts at the last follow up. Catch-up growth was observed in five patients after transplantation. Five school-aged patients attended school and received adequate grades and two adults worked full-time. Of the DDS patients, dysuria due to hypospadias persisted in one patient and treatment for hypogonadism was needed in one patient. CONCLUSIONS: CNS and DDS were diagnosed early after onset and adequate treatment was started. Growth and development after renal transplantation were relatively good. Thrombotic episodes or severe infection in CNS patients was difficult to manage and complications resulting from DDS affected the quality of life.

[Recurrence of sarcoidosis in a hemodialysis patient confirmed by abnormal calcium metabolism].

28-year-old man hospitalized for a fever of unknown origin. This patient was already diagnosed as neurosarcoidosis proven by brain biopsy in 1997, then entered chronic hemodialysis therapy in 2002. The data showed hypercalcemia without taking any calcium agent and vitamin D, also showed suppressed intact-parathyroid hormone and normalized 1,25-dihydroxyvitamin D even the condition of end stage renal failure. Recurrence of sarcoidosis was made in this hospitalization. The laboratory data as well as symptom improved after taking oral prednisolone. We reported the case of recurrent sarcoidosis in a hemodialysis patient confirmed by abnormal calcium metabolism.

Post-transplant early recurrent proteinuria in patients with focal glomerulosclerosis--angiotensin II immunostaining and treatment outcome.

We reviewed the transplantation data and results of histopathological studies with additional angiotensin II (AII) immunostaining of renal graft biopsies of nine cases (10 grafts) with recurrent proteinuria and three controls without recurrent proteinuria that received renal transplantation for primary focal segmental glomerulosclerosis (FSGS) between 1986 and 2002. Recurrent FSGS was confirmed in six grafts from nine cases by light microscopy. In cases with recurrent proteinuria, loss of graft function was noted in all six renal grafts received between 1986 and early 1992 but in none of four grafts received between late 1992 and 2002. Two of four patients of the late group but none of those of the early group received angiotensin converting enzyme (ACEI) or angiotensin II receptor blocker (ARB) with plasma exchange (PE). In control cases without proteinuria, AII immunostaining was detected in tubules but not in glomeruli in 1-hour biopsies as well as later on. In cases with recurrent proteinuria, AII immunostaining was detected in both tubules and glomeruli, although glomerular AII staining was not observed in 1-hour biopsies. Our results suggest that effective treatment of post-transplantation recurrent FSGS requires ACEI or ARB with PE in the absence of another etiology.

Development and application of serum cholinesterase activity measurement using benzoylthiocholine iodide.

BACKGROUND: Measurement of cholinesterase activity in serum is important to identify substantial liver disease and damage by pesticides, and to assess the degree of development of fatty liver and preoperative risk. Many procedures using various artificial substrates have been developed but suffer from problems with substrate specificity and interference by endogenous substances. METHODS: An assay pseudocholinesterase (ChE, EC 3.1.1.8 acylcholine acylhydrolase) activity was developed using a stable substrate specific to ChE, benzoylthiocholine iodide (BZTC). The thiocholine generated by hydrolysis of BZTC by ChE activity reacts with 2, 2'-dipyridildisulfide (2-PDS) to produce 2-thiopyridine (2-TP), which is measured at 340 nm. Optimum pH, buffer types and concentrations, substrate concentrations, and optimum conditions of the color reaction were investigated. The substrate specificity, test interferences, correlation with other measurement methods, and reference interval were evaluated. RESULTS: The optimum pH of this method was 7.8, and 3-[4-(2-hydroxyethyl)-1-piperazinyl] propanesulfonic acid (EPPS) buffer solution was selected. Constant activity was shown at buffer concentrations >200 mmol/l, and the maximum activity was shown at a substrate concentration of 0.2 mmol/l. When a Hill plot was utilized, the Hill number was 1.08 and 1.09. The reaction velocity at this substrate concentration was 94% of V(max). The K(m) of ChE to BZTC was between 1.2 x 10(-2) and 1.3 x 10(-2) mmol/l. The range was 0-300 U/l. The coefficients of variation (CV) for 20 measurements of serum containing 53.1, 96.6, and 270.7 U/l of ChE were 0.82%, 0.76%, and 0.54%, respectively. The relative reactivity of acetylcholinesterase (AChE) to this substrate was 2%. The correlation factors of this method to three other methods were between 0.993 and 0.998. CONCLUSIONS: This method provides excellent specificity, reproducibility, a wide measurement range, and minimal interference from endogenous substances to common serum analytes. Correlation of this method with conventional methods was good. Because the reagents are stable after preparation, this assay is useful for routine analysis.

Activation of nuclear factor-kappa B and macrophage invasion in cyclosporin A-and tacrolimus-treated renal transplants.

This retrospective study was designed to compare the efficacy of cyclosporin A (CyA) and tacrolimus (FK506) on chronic rejection (CR) associated with nuclear factor-kappa B (NF-kappaB) activation and macrophage invasion. Non-episodic day 50 protocol renal biopsy was performed in 63 consecutive patients with renal transplants from living donors, treated with either CyA or FK506. Southwestern histochemistry for NF-kappaB, immunostaining for CD68, and Banff classification were performed, and these findings were compared with outcome over 34 +/- 13 months. Compared with specimens from FK506-treated patients (n = 20), specimens from CyA-treated patients (n = 43) showed a significant increase in tubulointerstitial CD68-positive cells (1.5 +/- 0.9 vs. 0.9 +/- 0.8, p < 0.01), although no significant differences were observed in NF-kappaB activation. Specimens with Banff acute rejection (AR) grade > or = 1A (n = 20) showed increased macrophages (p < 0.01) compared with specimens with AR < 1A (n = 43). Specimens from patients with clinical AR prior to day 50 biopsy (n = 23) also showed increased macrophage invasion (p < 0.01) compared with specimens from patients without prior clinical AR (n = 40). The cumulative well-functioning (serum creatinine < 1.5 mg/dL) graft survival rate was significantly lower in patients with increased tubulointerstitial CD68-positive cells (n = 63, p < 0.05). Our findings suggest that tacrolimus is more effective than CyA against CR with respect to macrophage invasion and AR.

Detection of gender difference and epitope specificity of IgG antibody activity against IgA1 hinge portion in IgA nephropathy patients by using synthetic hinge peptide and glycopeptide probes.

BACKGROUND AND AIMS: There are many reports on the presence of an incompletely glycosylated O-linked oligosaccharide(s) on the IgA1 hinge region in some immunoglobulin (IgA) nephropathy patients. Furthermore, the production of an antibody against the naked hinge peptide portion was reported in an IgA nephropathy patient. In this report, characterization of the IgG antibody against the hinge portion was carried out by using synthetic hinge glycopeptide probes. METHODS AND RESULTS: The following synthetic hinge peptide and glycopeptides were prepared: 19mer peptide, V-P-S-T-P-P-T-P-S-P-S-T-P-P-T-P-S-P-S (designated HP), the peptide having a single alpha-linked GalNAc residue at positions 4, 7, 9, 11 and 15 (4 GN - 15 GN, respectively) and the same peptide having five GalNAc residues at all five positions (GN5). The mean value of the antibody activity against these probes was compared with each other. The highest activity against the naked hinge peptide (HP) and lowest activity against the fully glycosylated hinge peptide (GN5) were obvious. As attachment of GalNAc to position 4 or 11 on the peptide brought about a significant reduction of the activity against the naked hinge peptide, the P-S-T-P sequence included in both positions was thought to be the most probable site recognized by these antibodies. As an additional unexpected observation, a gender difference in this antibody activity against all the probes was found. The antibody activity in a female was significantly higher compared with that in a male. CONCLUSION: Because the frequency of incidence of IgA nephropathy is known to be slightly higher in males, this gender difference might indicate a protective meaning to remove aberrantly glycosylated molecules from the patient's serum.

Clinical outcome and accommodation in ABO incompatible kidney transplantation.

We performed 84 ABO-incompatible kidney transplants at Toho University since 1989, with plasmapheresis and exchange replacing AB blood group plasma as pre-conditioning to reduce anti-donor blood group antibodies. Our current immunosuppression protocol consists of basiliximab, MMF, steroid, and cyclosporine or tacrolimus, including splenectomy. Overall patient/ graft survival rates (n=84) were 95/93 at one year, 94/92 at 3 years, 87/80 at 5 years, 87/75 at 7 years, and 83/67 at 10 years. The outcomes are similar to those of ABO-compatible living donor transplants. We have achieved 100% graft and patient survival rates (n=48) for the 7 years since January 1997. Our findings suggest that post-conditioning is not necessary to control titers of anti-donor blood group antibodies or to overcome acute humoral rejection. Infection control is critical in achieving good outcomes in ABO-incompatible transplants. We found that only anti-donor blood group antibodies in blood group O recipients of ABO-incompatible kidneys were specifically suppressed one year after transplantation. This appeared to be a type of accommodation in which there was no immunological response despite the co-existence of donor antigen and antibody, and might have been caused by down-regulation of B cells to produce anti-donor antibody.

Living related kidney transplantation in a patient with autosomal-recessive Alport syndrome.

We discuss a patient with Alport syndrome who received a renal transplant from a donor with thin basement membrane disease. A 30-year-old woman, diagnosed with Alport syndrome on the basis of sensorineural hearing loss, characteristic renal biopsy findings and a family history of microhaematuria, entered chronic haemodialysis therapy. She then received a renal transplant donated from her father, who had sensorineural hearing loss and persistent microhaematuria. On the day of renal transplantation, a 1-h graft biopsy after reperfusion showed thin basement membrane disease. We re-tested the patient's native kidney biopsy specimen by immunohistochemical staining using alpha-chain-specific collagen type IV monoclonal antibodies. There was no expression of collagen type IV alpha3-, alpha4- and alpha5-chain on glomerular basement membrane, but positive staining of alpha5-chain on Bowman's capsular basement membrane was noted. A diagnosis of autosomal-recessive Alport syndrome was made. We concluded that this family might display different phenotypic expressions of the same genotype: one suffered end-stage renal disease and the other thin basement membrane disease.

ABO incompatible kidney transplantation --immunological aspect-.

ABO incompatible kidney transplantation (ABOINCKT) has been developed in Japan because of the shortage of cadaveric donors. We have performed 76 living-donor ABOINCKT in our center. Donor blood type antibody was removed by immunoadsorption or plasmapheresis and exchange. Immunosuppression consisted of cyclosporine or tacrolimus, steroid, and cyclophosphamide or azathioprine or mycophenolate mofetil and, recently, basiliximab. Splenectomy was routinely performed during the transplantation surgery. Donor blood type antigen was strongly expressed on the vascular endothelium at all time points and in all conditions posttransplantation. Red blood cell agglutination reaction (RBAR) was positive only in renal tissues from a patient with delayed hyperacute rejection. Donor specific antibody suppression was observed in 18 ABOINCKT recipients with blood type O from a donor with blood type A1 or B. ADCC activity was detected after pre-treatment. Acute humoral rejection in ABOINCKT can result from ADCC, as well as by antigen-antibody reaction. Five year graft and patient survival rates were 75% and 64% in 37 ABOINCKT recipients from June 1989 through December 1996, however they have been 100% in 39 ABOINCKT recipients since January 1997. Accommodation has been produced in ABOINCKT with the co-existence of blood type antigen and antibody. Currently, ABOINCKT is an alternative which should be considered, particularly for blood type O patients with extended waits for cadaveric transplantation and for pediatric patients.

A highly sensitive chemiluminescent reverse transcriptase assay for human immunodeficiency virus.

A simple and highly sensitive reverse transcriptase (RT) assay was developed by combining a previously reported non-radioisotopic RT assay with the use of a template-primer-immobilized microplate, an enzyme capture protocol, product digestion and a chemiluminescent substrate. The assay was able to detect directly the RT activity in serum samples, plasma and cell culture medium without the need for concentration and extraction of the enzyme. The assay was able to detect RT activity equivalent to 100 virions/ml of HIV-1. These results suggest that this highly sensitive chemiluminescent RT assay can be used not only for virological investigation but also for routine screening of biopharmaceuticals.