Structure-activity relationship studies of pyrogallol as a calcineurin/NFAT signaling suppressor.

Previously, we have shown that pyrogallol alleviated nasal symptoms and suppressed IL-9 gene up-regulation in allergy model rats by inhibiting calcineurin/NFAT signaling. As pyrogallol has antioxidative activity, it may be responsible for inhibiting calcineurin/NFAT signaling-mediated IL-9 gene expression. However, the relationship between antioxidative activity and suppression of IL-9 gene expression has not been elucidated yet. Here, we conducted the structure-activity relationship studies of pyrogallol and its structurally related compounds to understand the mechanism of IL-9 gene suppression by pyrogallol. 2, 2-Diphenyl-1-picrylhydrazyl radical scavenging assay showed that the antioxidative activity of catechol, resorcinol, phloroglucinol, and gallic acid is 60.1%, 10.4%, 18.8%, and 113.5% of pyrogallol, respectively. Catechol, resorcinol, and phloroglucinol did not suppress NFAT dephosphorylation. Gallic acid suppressed dephosphorylation of NFAT. Gallic acid also suppressed ionomycin-induced up-regulation of IL-9 gene expression with the IC50 value of 82.6 µM. However, catechol, resorcinol and phloroglucinol showed no suppressive activity. In addition, using gallic acid-immobilized beads, we isolated and identified Poly(U)-binding-splicing factor 60 (PUF60) as a pyrogallol binding protein. These results suggest that the antioxidative activity of pyrogallol is not likely to be the mechanism of IL-9 gene suppression. Data also suggest that PUF60 is one of its target molecules responsible for the suppression of calcineurin/NFAT signaling by pyrogallol.

On-Campus Nursing Training During COVID-19 in Japan: A Systematic Literature Review.

During the coronavirus disease 2019 (COVID-19) pandemic, nursing education in Japan recommended the implementation of on-campus practical training as a substitute for hospital-based clinical training. This study explores nursing students' experiences with on-campus nursing training as an alternative to clinical practice by clarifying its advantages and disadvantages. This review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analysis and we included 26 articles in this study. Our findings reveal both the advantages of acquiring nursing knowledge, basic skills, and membership among students. Contrastingly, many students failed to acquire skills related to patient communication and flexible nursing care. Thus, despite some strengths, on-campus training is not a complete replacement for clinical training. Although this method has benefits in emergency situations, it is desirable to consider other educational methods in preparation for future pandemics.

Lipid hydroperoxide-derived insulin resistance and its inhibition by pyridoxamine in skeletal muscle cells.

Oxidative stress is strongly associated with the onset and/or progression of diabetes. Under conditions of oxidative stress, lipid hydroperoxides are decomposed to reactive aldehydes that have been reported to induce insulin resistance by modifying proteins involved in insulin signaling. Pyridoxamine (PM) can inhibit the formation of advanced glycation/lipoxidation end products by scavenging reactive carbonyl species. Thus, PM has emerged as a promising drug candidate for various chronic conditions, including diabetic complications. In this study, L6 skeletal muscle cells were treated with 4-oxo-2(E)-nonenal (ONE), one of the most abundant and reactive lipid-derived aldehydes. Cellular insulin resistance was assessed by measuring insulin-stimulated glucose uptake using 2-deoxyglucose. ONE induced a time- and dose-dependent decrease in glucose uptake. Liquid chromatography/electrospray ionization-mass spectrometry analysis of the reaction between ONE and insulin receptor substrate 1 (IRS1) lysate identified multiple modifications that could disturb the interaction between IRS1 and activated IR, leading to insulin resistance. Pretreatment of the cells with PM restored the ONE-induced decrease in glucose uptake. Concomitantly, the formation of PM-ONE adducts in cell culture medium was increased in a PM-dose dependent manner. PM can therefore prevent lipid hydroperoxide-derived insulin resistance by quenching ONE. Supplementary Information: The online version contains supplementary material available at 10.1007/s43188-022-00155-z.

Usefulness of Machine Learning-Based Gut Microbiome Analysis for Identifying Patients with Irritable Bowels Syndrome.

Irritable bowel syndrome (IBS) is diagnosed by subjective clinical symptoms. We aimed to establish an objective IBS prediction model based on gut microbiome analyses employing machine learning. We collected fecal samples and clinical data from 85 adult patients who met the Rome III criteria for IBS, as well as from 26 healthy controls. The fecal gut microbiome profiles were analyzed by 16S ribosomal RNA sequencing, and the determination of short-chain fatty acids was performed by gas chromatography-mass spectrometry. The IBS prediction model based on gut microbiome data after machine learning was validated for its consistency for clinical diagnosis. The fecal microbiome alpha-diversity indices were significantly smaller in the IBS group than in the healthy controls. The amount of propionic acid and the difference between butyric acid and valerate were significantly higher in the IBS group than in the healthy controls (p < 0.05). Using LASSO logistic regression, we extracted a featured group of bacteria to distinguish IBS patients from healthy controls. Using the data for these featured bacteria, we established a prediction model for identifying IBS patients by machine learning (sensitivity >80%; specificity >90%). Gut microbiome analysis using machine learning is useful for identifying patients with IBS.

[Concept analysis of "Gojo" (mutual help)].

Objective　The purpose of this study is to redefine "Gojo" (mutual help) among residents and explore measures to develop it Gojo in the integrated community care system. In 2000, long-term care insurance accelerated Japan's movement toward an aging society, thus increasing the importance of Gojo. This study aims to clarify the conceptual definition it has come to acquire in recent years and explore ways it can be developed in comprehensive community systems.Methodology　Rodger's evolutionary concept analysis was utilized in the study. A keyword research was done using the term "Gojo" in the Japan Medical Abstracts Society (Ichushi Web) and CiNii Articles databases. The search period was from 2000 to 2016 (search date: August 30, 2016) and the database search formula was set to "Gojo/TA". Thirty documents were selected through random sampling and a total of 32 documents were selected for analysis, including landmark documents. A qualitative analysis was conducted on three frameworks: attributes (i.e., characteristics of Gojo), antecedents (i.e., factors affecting Gojo), and consequences (i.e., expected results for Gojo). These three frameworks represent how Gojo is used, the events occurring before it, and the events resulting from it, respectively.Results　The characteristics of Gojo were found to include "experiences of empathy toward residents' daily need for support," "awareness about the residents' efforts to support each other," and "interaction among residents who support other's daily needs." The factors affecting Gojo were identified to be "the need for daily life support beyond what self-help, social solidarity care, and governmental care can provide"; "interchange among residents"; "sharing needs for daily life support among residents"; and "a resident-led public system that promotes mutual support." Gojo's expected results were "a solution for residents' needs of daily support"; "promotion of self-help awareness"; "providing them with a role to enhance their purpose in life"; and "encouraging exchanges and relations between them."Conclusion　Gojo was defined as "the interaction between local residents who support their daily needs, have an empathic experience of the need for daily life support, and have the desire to support each other." In addition, the following points were suggested as measures necessary to expand Gojo. The residents must have sympathy for other residents who need daily life support, understand the benefits of supporting each other, and have a public support system, even if Gojo is led by the residents.

[Development and effectiveness of care preventive supporter training programs based on a literature review].

Objective　Many preventive care supporter (e.g. kaigo-yobo supporter) training programs, conducted to train community residents, are developed by municipalities. However, it is not necessary that only municipalities can train people effectively or efficiently. In this paper, we initially reviewed the relevant literature and clarified the definitions of concepts like "program contents" and "evaluation indicators," while also planning our own training programs. Later, we developed a program based on the review and examined the results.Methods　The literature of the training program was examined, and the training program was developed based on the result. Four researchers and three public health nurses from a community general support center, in the Otsuchi Town of Iwate Prefecture, developed a training program from June to September 2017. The training program developed was then conducted from October to November 2017. To evaluate the participants' satisfaction with the program, a self-report survey was conducted. To evaluate the outcomes of the program, we measured their degree of comprehension of their community's challenges, before and after the program.Results　The training program was divided into two parts following the literature review. In the first part, the content of the supporters' activities following the program was determined (Type A), and, in the second, the same content was evaluated by the participants within the program (Type B). Type A consisted of various aspects including both concrete knowledge and skills needed to conduct care preventiveactivities after the program. In Type B, there were many aspects-including both lectures and exercises-that aimed to increase the participants' awareness of community challenges, as well as inspection to learn about pioneering activities which helped them consider concrete care preventive activities following the program. In Otsuchi Town, we found it to be imperative for participants to consider how to respond to various situations and accordingly plan the training program for use in Type B. To evaluate the results, 12 participants were analyzed. Participants included two men and ten women, with an average age of 71.4±10.0 years [range: 53-88]. Comprehension levels of community challenges (3.1→4.1, P=0.046), as well as the confidence to actively involve themselves in their own preventive care strategies (3.4→4.0, P=0.035), significantly increased after involvement in the program. However, their confidence to work for community preventive care support groups (3.1→3.5, P=0.227) did not increase significantly.Conclusion　We clarified certain viewpoints, such as the purpose, content, and evaluation indices of community care training programs, by reviewing the relevant literature. Based on the discovered viewpoints, we were then able to obtain certain results through implementing our own training programs, thereby significantly increasing participant comprehension and confidence levels.

Inhibition effect of pyridoxamine on lipid hydroperoxide-derived modifications to human serum albumin.

Pyridoxamine (PM) is a promising drug candidate for treating various chronic conditions/diseases in which oxidative stress and carbonyl compounds are important factors affecting pathogenicity. These abilities of PM are mainly attributed to its inhibition of advanced glycation and lipoxidation end product formation, by scavenging reactive carbonyl species. PM might therefore prevent protein damage from lipid hydroperoxide-derived aldehydes such as 4-oxo-2(E)-nonenal (ONE) and 4-hydroxy-2(E)-nonenal (HNE) by trapping them. It was previously reported that PM reacts with ONE to produce pyrrolo-1,3-oxazine (PO8) through the formation of pyrido-1,3-oxazine (PO1/PO2). In this study, we found that ONE and HNE yield an identical product containing a pyrrole ring (PO7, PH2) upon reaction with PM. The structure of PO7/PH2 was shown by LC-MS and NMR analyses to be 1-(2-hydroxy-6-hydroxymethyl-3-methylpyridin-4-ylmethyl)-2-pentylpyrrole. PO1, PO7/PH2, and PO8 were the main stable PM-ONE/HNE adducts. In the incubation of human serum albumin (HSA) with ONE or HNE, Lys residues provided the most favorable modification sites for both aldehydes, and the number of HNE-modified sites was higher than that of ONE-modified sites. When HSA was allowed to react with a linoleic acid hydroperoxide in the presence of ascorbic acid, ONE modified more residues (10 Lys, 3 His, 2 Arg) than did HNE (8 His, 2 Lys), indicating the relative reactivity of aldehydes towards amino acid residues. Upon treatment with increasing concentrations of PM, the concentrations of ONE-modified HSA peptides, but not of HNE-modified peptides, were reduced significantly and dose-dependently. Concomitantly, the formation of PM-ONE adducts increased in a dose-dependent manner. The inhibition effect of PM was also confirmed in the cell system subjected to oxidative stress. Our results demonstrate that PM can inhibit lipid hydroperoxide-derived damage to proteins by trapping ONE preferentially, and the resulting PM-ONE adducts can be used as a dosimeter for ONE production to determine the levels of lipid peroxidation.

Pt-free carbon-based fuel cell catalyst prepared from spherical polyimide for enhanced oxygen diffusion.

The development of a non-precious metal (NPM) fuel cell catalyst is extremely important to achieve globalization of polymer electrolyte fuel cells due to the cost and scarcity of platinum. Here, we report on a NPM cathode catalyst prepared by the pyrolysis of spherical polyimide nanoparticles that contain small amounts of Fe additive. 60 nm diameter Fe-containing polyimide nanoparticles were successfully synthesized by the precipitation polymerization of pyromellitic acid dianhydride and 1,3,5-tris(4-aminophenyl)benzene with Fe(acac)3 (acac = acetylacetonate) as an additive. The particles were subsequently carbonized by multistep pyrolysis to obtain the NPM catalyst while retaining the small particle size. The catalyst has good performance and promising durability for fuel cell applications. The fuel cell performance under a 0.2 MPa air atmosphere at 80 °C of 1.0 A cm(-2) at 0.46 V is especially remarkable and better than that previously reported.

Cross-sectional study of social support and psychological distress among displaced earthquake survivors in Japan.

AIM: This cross-sectional study aims to explore the relationship between different types and sources of social support and psychological distress by age and sex among survivors living in temporary housing 10 months after the Great East Japan Earthquake. METHODS: Self-reported questionnaires/structured interviews administered from January to March 2012 recorded demographic characteristics, damage involving participants' families, social support, and psychological distress. RESULTS: Data on 296 participants aged 20 years or more from nine temporary housing complexes in Otsuchi were analyzed; K6 scores indicating psychological distress averaged 5.1 (standard deviation, 5.9; range, 0-24). Multiple logistic regression analyses indicated differences among types and sources of social support with regard to psychological distress by age and sex among disaster survivors. For men aged less than 65 years, social support by family was related to lower psychological distress. For women aged 65 years or more, emotional support from family, informational and instrumental support, and social companionship from friends in their own temporary housing complexes were related to less psychological distress. CONCLUSION: Differences in age and sex were related to different sources of social support in relation to psychological distress. It is necessary to pay more attention to those who lost family members in the disaster, especially men aged less than 65 years. It may also be necessary to support survivors in making friends when they relocate to temporary housing, especially women aged 65 years or more.

Follow-up study of the general and mental health of people living in temporary housing at 10 and 20 months after the Great East Japan Earthquake.

AIM: An earthquake of magnitude 9.0 and accompanying tsunami struck the Tohoku region in northeast Japan on 11 March 2011. The purpose of this study was to observe evacuees' health status such as general health, psychological distress, and feeling of isolation over time. METHODS: The authors distributed a questionnaire survey to residents of temporary housing in January to March (time 1) and again in October to December of 2012 (time 2). RESULTS: Two hundred respondents who filled out the questionnaire at both times were the subjects of this study. The self-reported general health in 39% and mental health status in 43.5% of the participants were poor at time 2. In addition, a higher percentage of participants felt a sense of isolation at time 2 even though more of the participants participated in community activities at that time. CONCLUSION: This result shows the evacuees' prolonged psychological distress and strengthening sense of isolation. It will be necessary to monitor them carefully and provide support continuously over the long term.

Inhibition of heat shock protein 27 phosphorylation promotes sensitivity to 5-fluorouracil in colorectal cancer cells.

The aim of the present study was to investigate whether the inhibition of HSP27 phosphorylation, which affects certain cellular functions, modulates sensitivity to 5-fluorouracil (5-FU) in colorectal cancer cells. Exposure to 5-FU in HCT116 and HCT15 cells expressing high levels of HSP27 with a low 5-FU sensitivity caused a minimal change in HSP27 expression, but induced the upregulation of HSP27 phosphorylation, particularly at Ser78. By contrast, exposure to 5-FU in HT29 cells expressing a low level of HSP27 with a high 5-FU sensitivity marginally increased HSP27 expression, with minimal phosphorylation. Treatment with a selective inhibitor, p38 mitogen-activated protein kinase (MAPK; SB203580), caused the dose-dependent suppression of HSP27 phosphorylation, which was upregulated by 5-FU, reducing the half maximal inhibitory concentration values of 5-FU in the HCT116 and HCT15 cells. However, treatment with SB203580 exhibited no significant effect on cell growth or survival. In conclusion, this study indicated that the inhibition of HSP27 phosphorylation by a selective inhibitor of p38 MAPK promotes 5-FU sensitivity without causing cytotoxicity in colorectal cancer cells.

Electroreductive dechlorination of chlorophenols with Pd catalyst supported on solid electrode.

Electroreductive dechlorination of chlorophenols with Pd catalyst supported on solidelectrode was studied. As solid electrodes, carbon cloth (CC), carbon felt (CF) and titanium mesh were used, and palladium was plated on solid electrodes by either electrolytic or electroless method. On each electrode with Pd, chlorophenols were qualitatively dechlorinated to phenol, while they were entirely intact on electrodes without Pd. Moreover, neither base electrode nor plating method significantly affected the activity of Pd as far as it was sufficiently loaded on the electrode. Based on the results in the experiments using one electrode repeatedly, Pd catalyst proved to possess a satisfactory duarability under the present condition. It was suggested that the reactive species responsinble for the dechlorination of chlorophenols could be formed during preliminary electrolysis. Thus, (Pd)x-H resulting from the adsorption of electrogenerated hydrogen on metallic Pd might be assumed most probable.

Suppression of heat shock protein 27 expression promotes 5-fluorouracil sensitivity in colon cancer cells in a xenograft model.

The present study investigates whether the expression levels of heat shock protein 27 (HSP27) in colon cancer cells are associated with 5-fluorouracil (5-FU) sensitivity in a xenograft model, as well as the mechanism responsible for regulating 5-FU sensitivity. HCT116 cells which have a high expression of HSP27 were stably transfected with specific short hairpin RNA (shRNA) in order to suppress HSP27 expression. The association between HSP27 protein expression levels and 5-FU sensitivity was evaluated in a mouse xenograft model. The mRNA expression of 5-FU metabolic enzymes and cell apoptosis were also analyzed in the transfected cells. The suppression of HSP27 protein expression led to enhanced 5-FU sensitivity. The mRNA expression levels of dihydropyrimidine dehydrogenase and orotate phosphoribosyltransferase, but not those of thymidylate synthase, and the number of apoptotic cells increased in the transfected cells after 5-FU exposure. In conclusion, the suppression of HSP27 expression in colon cancer cells may promote 5-FU sensitivity by inducing apoptosis, despite the acceleration in 5-FU metabolism.

[FOLFIRI with bevacizumab chemotherapy for a patient with recurrence of rectal cancer under haemodialysis for chronic renal failure].

As pharmacokinetics in patients undergoing haemodialysis is different from patients with normal renal function, it remains unclear whether chemotherapy can be performed safely for patients with haemodialysis as well as those who have normal renal function. Here, we report a case with recurrence of rectal cancer who received FOLFIRI with bevacizumab chemotherapy under haemodialysis, and obtained good tumor control. A 47-year-old woman had undergone haemodialysis for 10 years due to chronic renal failure. At 45 years of age, she received abdominoperineal resection due to rectal cancer (pStage II). Four months after the surgery, liver metastasis was found, for which partial resection of the liver and adjuvant chemotherapy [UFT (400 mg/body)/UZEL (75 mg/body)] were performed. Eighteen months after the liver resection, multiple lung metastases were found. Therefore, intensive chemotherapy using FOLFIRI (CPT-11: 90 mg/m2) with bevacizumab (2.5 mg/m2) was performed. Severe neutropenia (grade 3, 4), but not non-hematologic adverse events such as diarrhea and bevacizumab-specific adverse events, was observed. As she did not recover easily from neutropenia in spite of treatment with G-CSF, a dose reduction of the FOLFIRI regimen was gradually performed. Although chemotherapy was conducted approximately monthly, the tumor response reflected a stable disease 8 months after 8 courses of chemotherapy. We suggest that it is important to investigate the pharmacokinetics of toxic agents such as CPT-11, (SN38) for dose modification, and for the safe and continuous chemotherapy of patients receiving haemodialysis.

Induction and maintenance of anti-influenza antigen-specific nasal secretory IgA levels and serum IgG levels after influenza infection in adults.

OBJECTIVES: To determine the induction and changes in anti-influenza virus secretory IgA (s-IgA) levels in nasal washes and serum IgG levels in patients with influenza. METHODS: The study recruited 16 patients with influenza aged 35.6 ± 9.6 years in 2007/2008 and 2008/2009 seasons. Nasal washes and serum were obtained throughout the first year. Anti-viral s-IgA levels and neutralization activities in nasal washes, and serum anti-viral IgG levels and hemagglutination inhibition (HI) titers were measured. RESULTS: Anti-viral(H1N1) s-IgA to total IgA ratio and neutralizing antibody titer were low in nasal washes of all patients, whereas serum levels of anti-viral IgG and HI titers varied widely at day 1.4 ± 1.0 postinfection. Both nasal s-IgA and serum IgG levels later increased significantly, reaching peak levels at day 9.6 ± 3.3 postinfection. The induced nasal s-IgA then returned toward the initial levels within 300 days, although the levels at day 143 ± 70 were 3.03-fold of the initial. Individual serum IgG levels also returned toward the initial levels within 300 days, although the mean levels remained high probably because of re-infection in a subgroup of patients. Although influenza A (H3N2) was a minor epidemic subtype in both flu seasons, a significant rise in nasal anti-viral (H3N2) s-IgA levels and a slightly increase in serum IgG levels were noted. CONCLUSION: Low levels of nasal anti-viral s-IgA and neutralizing antibody were noted compared with a wide range of serum anti-viral IgG and HI titers at the onset of infection. Elevated s-IgA and IgG returned toward the initial levels within 300 days of infection with minor exceptions.

[New operation for sulcus vocalis--laser vaporization of the sulcus with fat injection].

Although several treatments for sulcus vocalis have been reported, the condition continues to be known as an extremely intractable vocal disorder even now. We report the good outcome of a new treatment for sulcus vocalis. The operation was performed under intubated general anesthesia. We aspireted abdominal fat using an 18-gauge needle and a 20 = cc disposal syringe first. After collection of the fat, laryngomicrosurgery and laser vaporization of the sulcus bilaterally was performed using a KTP laser. Then, the collected fat was injected into the thyroarytenoid muscle bilaterally (about 1cc on each side). Seven patients underwent this surgery. The voice, as evaluated auditorily, improved in all the cases and the maximum phonation time increased in 6 of the 7 cases. We attribute the vocal improvement to the formation of new free edges of the vocal folds after this surgery.

Examination of conditions inhibiting the formation of acrylamide in the model system of fried potato.

Acrylamide (AAm) is produced in food through the reaction of asparagine and reducing sugar. We examined several methods of reducing the level of AAm using potato tubers. The fried model system that we employed consisted of thin slices that were first treated in water under different conditions before frying. A sufficient amount of water present in the fry material acts as an inhibitor against the formation of AAm and allows only a negligible amount of AAm to form. It was found that given the low content of water, the fry material temperature was sufficiently high to allow a relatively large level of AAm to form. Examination of water treatment prior to frying revealed that higher-temperature treatment water and longer treatment time resulted in the formation of lower levels of AAm. Moreover, removing some of the residual heat had an inhibiting effect on the formation of AAm.

Formation of acrylamide in a processed food model system, and examination of inhibitory conditions.

Acrylamide (AAm) is formed from asparagine (Asn) and reducing sugar during cooking of foods at high temperature. We examined the formation of AAm in a model system using a glass fiber filter paper, and looked for suitable conditions for inhibiting AAm formation. In frying, the formation rate was about 10 times that in a moistureless oven. Increase of frying temperature and frying time increased AAm formation when the residual moisture was 5% or less. AAm increased with increasing amount of glucose (Glc) addition up to 1:1 with respect to Asn, but then decreased. On the other hand, in the case of fructose, as the amount added was increased, AAm increased accordingly. The AAm formation rate with respect to Asn increased when valine (Val) was co-present in a Glc and Asn reaction system. Cysteine and lysine inhibited the AAm formation rate. Pathways for the formation of AAm are proposed.

Dechlorination of polychlorinated organic compounds by electrochemical reduction with naphthalene radical anion as mediator.

Electrochemical reduction with electrochemically generated naphthalene radical anion in N,N-dimethylformamide was applied to the dechlorination of five representative POPs, namely HCB, lindane, DDT, PCP and aldrin. Rapid and complete dechlorination was possible for lindane and DDT to give nearly quantitative yields of benzene and 1,1-diphenylethane, respectively. HCB was reduced through complex reaction pathways to yield unknown products. Dechlorination of PCP and aldrin beyond dichlorinated compounds was difficult because of their very negative reduction potential. The reaction pathways for each dechlorination were proposed with the identification of intermediates.

Dechlorination of PCBs by electrochemical reduction with aromatic radical anion as mediator.

Mediated electrochemical reduction was applied to the dechlorination of polychlorinated biphenyls (PCBs) in tetra-n-butylammonium perchlorate/dimethylformamide solution. Rapid and complete dechlorination was possible with biphenyl or naphthalene as the mediator, whereas the reaction was much slower with anthracene or 9,10-diphenylanthracene. The reaction rate was so high with naphthalene or biphenyl radical anion that differences in reactivity could not be observed between congeners. Side reactions, other than biphenyl formation, could occur depending upon the mediators and the substrates, but contributed less than 10% of the total products in the case of naphthalene-mediated dechlorination. Almost all chloride ion formed in the dechlorination remained in the cathode solution. The order of the reaction was determined to be 0.5 for the substrate and 1 for the mediator (naphthalene) in the dechlorination of 2-chlorobiphenyl; identical to results for the mediated dechlorination of 1-chloronaphthalene. The reaction rate in practical PCB dechlorination could be estimated with the use of the initial concentration of the mediator and chlorine content of the solution provided that the problem of the deactivation of the electrode surface could be solved.