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One of the survival mechanisms of root-knot nematodes (Meloidogyne spp.) in the absence of host plants during hot and dry summer seasons is anhydrobiosis of second-stage juveniles (J2). Another strategy might be migration of J2 to deeper soil to avoid high soil temperatures and low humidity. Wetting infested soil during such seasons is sometimes suggested as a nematode control method that prevents anhydrobiosis, leading to exhaustion of their energy reserves. Population densities of Meloidogyne javanica at five soil depths (0–50 cm) in irrigated and nonirrigated field plots were estimated during three summer months in two successive years after uprooting infected tomato plants. The number of J2 in the soil was estimated by counting J2 extracted by Baermann funnel extraction and number of root galls on lettuce seedlings grown in the soil samples. Significant factors for J2 survival were number of days after plant removal and soil depth, probably due to lower maximum daily soil temperatures and higher water contents at depth. Irrigation did not consistently affect the number of extracted J2 or root galls. No obvious evidence of J2 migration from the upper to deeper soil layers or nematode-control effects of the irrigation were observed.

Chitinases are generally composed of multiple domains; a catalytic domain and one or more additional domains that are not absolutely required but may modify the chitinolytic activity. The LinChi78 chitinase from Listeria innocua has a catalytic domain (CatD), a fibronectin type III-like (FnIII) domain, a chitin-binding domain (ChBD), and an unknown-function region (UFR) located between the CatD and FnIII domains. The UFR is 146 amino acid residues in length and does not have a homologous domain in the Conserved Domain Database. We performed a functional analysis of these domains and the UFR using several C-terminally and internally deleted mutants of LinChi78. Hydrolysis of an artificial substrate was almost unaffected by deletion of the ChBD and/or the FnIII domain, although the ChBD-deleted enzymes were approximately 30% less active toward colloidal chitin than LinChi78. On the other hand, deletion of the UFR led to an extensive loss of chitinase activity toward an artificial substrate as well as polymeric substrates. Upon further analysis, we found that the GKQTI stretch, between the 567th (G) and 571th (I) amino acid residues, in the UFR is critical for LinChi78 activity and demonstrated that Gln569 and Ile571 play central roles in eliciting this activity. Taken together, these results indicated that LinChi78 has a unique catalytic region composed of a typical CatD and an additional region that is essential for activity. Characterization of the unique catalytic region of LinChi78 will improve our understanding of GH18 chitinases.

BACKGROUND Nematode attractants could serve in nematode control strategies by combining with chemical or biological nematicides or by interrupting the nematodes' host-finding process. The attractiveness of some benzenoid aromatic compounds, mainly benzoic acids, alcohols, aldehydes and phenols, to second-stage juveniles (J2) of four Meloidogyne species (M. hapla, M. incognita, M. javanica and M. marylandi) was evaluated by using trap tubes and balls filled with washed dune sand buried in nematode-inoculated sand in Petri dishes. RESULTS Two-methoxybenzaldehyde, 2-methoxycinnamaldehyde, 2-hydroxybenzoic acid (salicylic acid), 2-hydroxy-3-methoxybenzaldehyde (o-vanillin), 3-methoxybenzoic acid, 4-methoxybenzoic acid and trans-cinnamic acid effectively attracted J2 of all or most of the four Meloidogyne species to trap tubes in a one-compound assay. When nematodes were exposed to three different compounds simultaneously in the three-compound assay, J2 of all Meloidogyne species were attracted mainly to 2-methoxycinnamaldehyde, salicylic acid and 4-methoxybenzoic acid. Exceptions were M. hapla J2, which were not attracted to salicylic acid. In the soil column assay, M. javanica and M. incognita J2 were attracted upward to 4-methoxybenzoic acid in a trap ball located 4 or 8 cm above the inoculation point, whereas salicylic acid and 3-methoxybenzoic acid demonstrated slight, if any attraction. CONCLUSION Although some of the tested compounds exist in root exudates, it is not clear whether they are involved in the nematode host-searching process in nature. The attractants found in the study have potential for use in Meloidogyne species control, probably as a nematode trap constituent or as compounds that disrupt the nematodes' host-finding process. © 2021 Society of Chemical Industry.

Background Nonfumigant nematicide efficacy is affected by several factors, such as nematode species and environmental conditions. However, the influence of nematodes' physiological status on nematicide efficacy is unknown. Inactive nematodes, such as those in quiescence or dormancy, seem to be more tolerant to nematicides than active ones. Second-stage juveniles of Meloidogyne species were inactivated by low temperatures and reversible nematicides before and during exposure to fluensulfone. The sensitivity of inactive juveniles to fluensulfone the nematicide was compared to that of active juveniles by EC50 (median effective concentration) for juvenile immobilization and root gall reduction. Results Inactivating Meloidogyne hapla and Meloidogyne javanica juveniles at 5 °C increased the EC50 (median effective concentration) of fluensulfone for immobilization of and root galling by Meloidogyne spp. 3.6 to 9.5 times. When the exposure temperature was decreased from 25 to 15 °C, EC50 for M. javanica root gall reduction after 24 and 48 h exposure increased 3.1 and 4.9 times, respectively, whereas for M. hapla, it increased 2.3 and 2.0 times, respectively. Juveniles of M. javanica and M. incognita immobilized by fenamiphos were as sensitive to fluensulfone as active juveniles based on the number of root galls. However, juveniles of these species immobilized by fluopyram were more tolerant to fluensulfone than untreated active juveniles. An interaction of fluopyram and fluensulfone activities is suggested. Conclusion Changes in the sensitivity of inactive Meloidogyne spp. juveniles to fluensulfone depend on the inactivation method. Fluensulfone could be better applied when nematodes are active in the soil. © 2020 Society of Chemical Industry.

BACKGROUND Restrictions on soil fumigants are prompting the development of new compounds for controlling nematodes, other soilborne pathogens and weeds. We evaluated the nematicidal activity of five bromine compounds against Meloidogyne javanica in vitro, and tested the two most effective ones against Pratylenchus penetrans and Xiphinema index in vitro and in soil. RESULTS Only allyl bromide and dibromo(nitro)methane showed nematicidal activity against M. javanica juveniles in vitro at

BACKGROUND The fluoroalkenyl fluensulfone, known to have strong nematicidal activity against Meloidogyne spp. (root-knot nematodes), was evaluated in vitro and in soil against the migratory nematodes Bursaphelenchus xylophilus, Aphelenchoides besseyi, Aphelenchoides fragariae, Ditylenchus dipsaci, Pratylenchus penetrans, Pratylenchus thornei and Xiphinema index. RESULTS B. xylophilus and D. dipsaci were not immobilised by 48 h in vitro exposure to up to 16 mg L−1 of fluensulfone. A. besseyi and A. fragariae were affected by 8 mg L−1, the highest concentration used for these nematodes. More than 60% of P. penetrans and P. thornei were immobilised by 4 mg L−1 of fluensulfone; however, exposure of P. penetrans to the compound prior to inoculation did not affect their root penetration ability. The immobilisation rate of X. index was increased by 48 h exposure to even 1.0 mg L−1 of fluensulfone. Incorporation of over 2 mg L−1 of fluensulfone into the soil reduced populations of P. penetrans and P. thornei before and after planting lettuce and chickpea respectively. The efficacy of fluensulfone against the tested nematodes was the same or higher than that of fenamiphos in most cases. CONCLUSION A. besseyi, A. fragariae, B. xylophilus and D. dipsaci were tolerant to fluensulfone and fenamiphos. P. penetrans, P. thornei and X. index were affected by fluensulfone, but nematicidal activity was much lower than that reported for root-knot nematodes. © 2014 Society of Chemical Industry

The goal of this study was to investigate the gas holdup, bubble size distribution, and Sauter mean diameter for oxygen micro-bubble dispersions in water in an acrylic-acid resin column with an inner diameter of 0.15 m, and with a working liquid height varying from 0.500 to 1.850 m. The micro-bubbles, which varied in their Sauter mean diameters from 32 to 40 μm depending on the gas velocity, were employed to measure their superior mass transfer properties, which are enhanced by the effects of self-compression and shrinking. The apparent liquid-side mass transfer coefficient, k L a , in the micro-bubble column was also measured using the transient absorption from oxygen micro-bubbles into degassed water or into nitrogen-desorbed water. The obtained values of k L a for oxygen absorption into the degassed water were significantly greater than those for absorption into nitrogen-desorbed water. The k L a values for the degassed water were represented well by the complete absorption model, and generally increased with increasing gas flow rate. It was found that the oxygen absorption efficiency, which was defined by the ratio of the absorption rate to the supply rate of oxygen, decreased with increasing gas flow rate and increased with increasing liquid depth. The oxygen absorption efficiency could be described well by an empirical correlation in terms of the ratio of the liquid height to the superficial gas velocity, h / U G , or in terms of the ratio of the liquid height to the linear gas velocity, h /( U G / e G ).

Ochradenus baccatus is a widely distributed shrub in desert regions of the Middle East and North Africa. This plant’s nematicidal activity against the root-knot nematode Meloidogyne javanica was evaluated because it has been found to contain exceptionally high levels of glucosinolates. In in vitro assays with aqueous extracts of the plant, 100% of second-stage juveniles were immobilized after exposure to 4% root-core extract for 48 h; 8% root-core extract suppressed their hatching by 87%, whereas stem, flower and root bark showed lower activity. Incorporation of root core or bark into the soil, as fresh or dry powder at 1 and 05% (w/w), respectively, reduced the number of nematodes recovered from the soil by 95–100%, whereas the flower and stem were much less effective. Results from further pot experiments indicated that only the root bark consistently contains nematicidal compounds which are effective in soil, whereas the nematicidal activity of the root core in soil was inconsistent. The presence of non-volatile lipophilic and lipophobic nematicidal compounds in the root bark was suggested by extraction with different polar solvents, but these compounds do not seem to be isothiocyanates – glucosinolate-hydrolysed compounds with nematicidal activity. Very poor host status of Ochradenus baccatus to M. javanica, M. incognita and M. hapla, but with root-penetration rates of juveniles similar to those in tomato roots, suggest that this plant may be used as a cover plant or trap plant to reduce nematode populations in the soil.

BACKGROUND Fluensulfone, a fluoroalkenyl group nematicide, has proved to be very effective in controlling root-knot nematodes, Meloidogyne spp. The authors evaluated some soil environmental factors that might affect its nematicidal activity. RESULTS Meloidogyne javanica juveniles exposed to fluensulfone lost their infectivity, even though they were rinsed in water when they were still active. Exposure of juveniles to fluensulfone at >1 mg L−1 for 48 h was very effective in reducing root galls. Peat as organic matter added to soil reduced nematicidal efficacy against M. javanica in pot experiments. Peat added to a soil column inhibited the downward movement of fluensulfone. The movement of fluensulfone was faster in sandy vs loess soil. Repeated soil application of fluensulfone did not reduce the nematicidal activity of fenamiphos or cadusafos, and repeated applications of these nematicides did not lower the nematicidal activity of a subsequent application of fluensulfone. CONCLUSION Fluensulfone nematicidal activity and movement were affected by organic matter and clay content, probably via adsorption. Enhanced biodegradation or cross-biodegradation of fluensulfone by other compounds was not observed. Soil environment should be considered to obtain effective nematode control efficacy with a given compound. © 2013 Society of Chemical Industry

Nematicidal activity of the leaf powder, leaf extracts and formulated leaf extracts of Myrtus communis, an evergreen shrub that is widely distributed in Israel and other Mediterranean countries, was evaluated using the root-knot nematode Meloidogyne javanica in in vitro and pot experiments. Leaf powder added to sand at 0·1% (w/w) reduced the number of juveniles recovered from the sand by more than 50%. Reduction in galling index and number of nematode eggs on tomato roots was also observed by incorporating the leaf powder at 0·1–0·4% (w/w) in the soil in pot experiments. Leaf powder extracts with methanol or ethanol showed the highest nematicidal activity among all extracts tested. Emulsifiable concentrates of leaf-paste extract at a concentration as low as 0·005% (a.i., w/w) reduced the number of juveniles recovered from treated sand and the gall index of cucumber seedlings. The extract paste at 26 g m−2 was also effective in reducing the gall index of tomato plants in field-plot experiments. The leaf powder at 0·2% and the formulated leaf-paste extract at 0·02% were also nematicidal to Tylenchulus semipenetrans and Ditylenchus dipsaci, but not to Pratylenchus penetrans or Steinernema feltiae. At least three nematicidal compounds were found in the leaf extract upon fractionation by thin-layer chromatography. The results suggest that the leaf powder and paste extract of M. communis are potential nematicides against root-knot nematodes.

Many nematicidal compounds with a variety of chemical structures have been isolated from various plant families, particularly the Asteraceae. Nematicidal activity of Verbesina encelioides (Asteraceae) was tested against the root-knot nematode Meloidogyne javanica. Nematicidal activity of V. encelioides extracts, fresh plant parts and their respective powders was tested against M. javanica in in-vitro and pot experiments. Aqueous extracts of the fresh flower showed the strongest nematicidal activity, followed by leaf and stem extracts. The number of viable nematode juveniles in soil was greatly reduced by mixing in dry and fresh flowers or leaves at concentrations of 0.1 and 1.0%, respectively. A powdered V. encelioides leaves added to nematode-infested soil at a concentration of 0.2% decreased root-galling index and the number of nematode eggs on roots. The nematicidal compound(s) in the flower and leaf could be extracted in water, methanol and ethanol, but not in acetone, ethyl acetate or n-hexane. The plant was found to be a non-host to M. javanica, M. incognita and M. hapla. Verbesina encelioides might serve as a green manure or its extracts as a nematicides for the control of root-knot nematodes.

BACKGROUND: Fluensulfone, a new nematicide of the fluoroalkenyl group, has proved to be very effective in controlling root-knot nematodes, Meloidogyne spp., by soil application. The systemic activity of this compound against M. incognita on peppers via soil drenching and foliar spray was evaluated. RESULTS: Root application of fluensulfone via soil drenching showed slight and no nematode control activity when applied 4 and 10 days, respectively, after inoculation. A single foliar spray of peppers with a fluensulfone solution at 3.0 g L−1 prior to inoculation reduced the galling index by 80% and the number of nematode eggs by 73–82% of controls. The reduction in these parameters by fluensulfone was much higher than that obtained with oxamyl or fenamiphos at the same concentration. This activity was also observed when the plants were sprayed 21 days before inoculation. A series of experiments suggested that foliar spray with fluensulfone prior to inoculation reduces nematode invasion. However, foliar spray after inoculation did not inhibit nematode development inside roots. CONCLUSION: Fluensulfone showed relatively high nematode control activity when sprayed on the foliage before inoculation. Fluensulfone may be used as a foliar application, in addition to soil application, for root-knot nematode control. Copyright © 2011 Society of Chemical Industry

The responses of diverse cucurbit accessions, including cucumber, melon, watermelon, pumpkin, and Momordica spp., to Meloidogyne javanica and M. incognita, were evaluated. For melons and cucumbers, severity of galling was significantly affected by nematode species, but no significant effects of cultivars or cultivar x nematode species interactions on the level of galling were observed. Severity of galling was always higher for M. incognita than for M. javanica in any cultivar tested. Galling indices in melons were 0.3 and 1.6, and in cucumber 2.8 and 3.7, for M. javanica and M. incognita, respectively. Watermelon did not did show root galling when inoculated with M. javanica and showed a very low index (0-0.3) with M. incognita. Cucurbita accessions evaluated were the most susceptible. Galling index in pumpkin inoculated with M. javanica was significantly lower than that caused by M. incognita. Cucurbita moschata and the intraspecific hybrids of C. moschata were more resistant than commercial cultivars of...

BACKGROUND: The small number of available nematicides and restrictions on the use of non-fumigant nematicides owing to high toxicity to human and non-target organisms hinder effective nematode control. The nematicidal efficacy of MCW-2, a new nematicide of the fluoroalkenyl group, was evaluated against the root-knot nematode Meloidogyne javanica (Treub.) Chitwood. RESULTS: MCW-2 showed irreversible nematicidal activity against second-stage juveniles of M. javanica in vitro, following exposure for 48 h at concentrations as low as 0.5 mg L−1, in contrast to fenamiphos or cadusafos. When exposed to MCW-2 for shorter periods, motile juveniles became immobile with time after rinsing in water. MCW-2 at 8 mg L−1 inhibited nematode hatching, which, however, recovered after rinsing in water. In pot and plot experiments, 0.5 mg MCW-2 L−1 soil and 2 kg MCW-2 ha−1, respectively, controlled M. javanica similarly to or better than fenamiphos or cadusafos at the same concentrations or at their recommended doses. In the soil, the nematicidal activity of MCW-2 was less persistent than that of fenamiphos. CONCLUSION: MCW-2 has potential to be used as a new non-fumigant nematicide that probably has a novel mode of action. Copyright © 2009 Society of Chemical Industry

Background: Magnetocardiography (MCG) is a new technique for visualizing a current distribution in the myocardium. In recent years, current distribution parameters (CDPs) have been developed based on the distribution. The CDPs reflect spatial-time current abnormalities in patients with coronary heart disease (CHD). However, the criteria and scoring method of the abnormalities using CDPs are still controversial. Method: We measured MCG signals for 101 normal controls and 56 CHD patients (single-, double-, and triple-vessel diseases) using a MCG system. The CDPs (maximum current vector [MCV], total current vector [TCV], current integral map, and current rotation) during ventricular repolarization were analyzed. To evaluate the CDPs that are effective in distinguishing between normal controls and CHD patients, the areas under the receiver operating characteristic curve (Az) are calculated. Furthermore, the total scores (“0” to “4”) of four CDPs with high Az values are also calculated. Results: MCV and TCV angles at the T-wave peak had the highest Az value. Furthermore, TCV angular differences between the ST-T segment also had high Az values. Using the four CDPs, the averaged total score for patients with triple-vessel disease was the highest (“2.67”) compared to the other groups (normal controls: 0.53). Furthermore, based on the assumption that subjects with a total score over “1” were suspected of having CHD, sensitivity and specificity were 85.7% and 74.3%, respectively. Conclusion: We concluded that the score and criteria using MCV and TCV during repolarization in CHD patients can reflect lesion areas and time changes of electrical activation dispersion due to ischemia.

Hydroponic culture media were tested after growing tomato, okra, cucumber and bean for their effect on hatching and mobility of Meloidogyne incognita second-stage juveniles (J2) in laboratory experiments. Tomato and okra culture media increased the numbers of J2 that hatched as compared to those in water or fresh culture medium. The tomato culture medium increased hatching even in the presence of fosthiazate, an organophosphate nematicide, and at a concentration that inhibited hatching in the absence of tomato culture medium. Neither heat treatment of the tomato culture medium nor change of pH abolished its hatching stimulatory activity. When active J2 were incubated in the tomato culture media, the percentages of nematodes that became quiescent were lower than those of nematodes incubated in water or in fresh culture medium for 3 and 7 days in two trials. Moreover, the sigmoid movement of J2 was faster in the tomato culture medium than in water. Quiescent J2 became active more rapidly in culture media of tomato, cucumber and okra than in water or fresh culture medium. In experiments using soil containing quiescent J2, more J2 were extracted with the Baermann funnel method from soil treated with tomato culture medium than from soil treated with water. The results confirm that nematode stimulants, which may serve as a potential means in nematode control, exist in the plant culture media.

The effect of recombinant interferon-alfa on serum HCV RNA levels in Japanese patients with chronic hepatitis C was investigated. At 24 weeks of treatment, 41 (32.5%) of 126 patients lost HCV RNA from serum, and aminotransferases were normalized in 31 (75.6%) of these 41 cases. HCV genotypes were categorized into four types (Type I, II, III, IV); the frequencies among the patients were: Type I: 0%, Type II: 70.6%, Type III: 20.6%, and Type IV: 6.3%. At the end of the 24-week treatment, HCV RNA levels were remarkably decreased in Type III patients and became undetectable in 18 (69.2%) of 26. In contrast, only 18 (20.2%) of 89 patients with Type II and two of eight with Type IV lost HCV RNA from sera. The relation between HCV genotype (Type III) and response to IFN therapy was also confirmed using a logistic regression model. HCV genotype seems to be an important factor in determining the response to IFN in patients with chronic hepatitis C.

Background: We need to know the magnetocardiogram (MCG) features regarding waveform and two-dimensional current distribution in normal subjects in order to classify the abnormal waveform in patients with heart disease. However, a standard MCG waveform has not been produced yet, therefore, we have first made the standard template MCG waveform. Methods and Results: We used data from 464 normal control subjects' 64-channel MCGs (268 males, 196 females) to produce a template MCG waveform. The measured data were averaged after shortening or lengthening and normalization. The time interval and amplitude of the averaged data were adjusted to mean values obtained from a database. Furthermore, the current distributions (current arrow maps [CAMs]) were calculated from the produced templates to determine the current distribution pattern. The produced template of the QRS complex had a typical shape in six regions that we defined (M1, M2, M3, M4, M5, and M6). In the P wave, the main current arrow in CAMs pointing in a lower-left direction appeared in M1. In the QRS complex, the typical wave appeared in each region, and there were two main current arrows in M2 and M5. There were negative T waves in M1, M4, and M5, and positive T waves in M3 and M6, and the main current arrow pointing in a lower-left direction appeared in M2. Conclusion: Template MCG waveforms were produced. These morphologic features were classified into six regions, and the current distribution was characterized in each region. Consequently, the templates and classifications enable understanding MCG features and writing clinical reports.

Background:The magnetocardiogram (MCG) is a promising medical tool for detecting and visualizing abnormal cardiac electrical activation in heart-disease patients. However, there is no large-scale MCG database of healthy subjects, and there is little knowledge of gender- and age-related influences on MCG data. Methods and Results:We obtained MCG data from 869 subjects (554 men, 315 women) using a conventional 64-channel MCG system, which covers the whole heart. Electrocardiogram (ECG) data were also obtained; 464 people (268 men, 196 women) were identified as a normal group using ECG data. Time intervals (PQ, QRS, QT, and QTc), current distributions (maximum current vector (MCV), and the total current vector (TCV)) of MCG data of the 464 normal subjects were analyzed to obtain basic MCG parameters. Although mean values of PQ and QRS intervals of the male subjects were slightly longer than those of the female subjects, no intervals were correlated with gender or age. The correlation between PQ intervals of ECG and those of MCG was better than the correlation between QRS and QT intervals of ECG and those of MCG. Both MCV and TCV angles were much smaller than the electrical-axis angle in ECG. Although TCVs of the QRS and T waves were stable, the women's mean T-wave-TCV angles significantly increased with age. The maximum amplitude of the P wave was about 1.7 pT, and the value of the QRS complex was about 20–25 pT. Moreover, the T-wave amplitude decreases with age. Conclusion:The MCG standard space-time parameters determined here provide a normal range for MCG parameters.