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19. Phylogenetic characterization of Isospora jaracimrmani oocysts from a veiled chameleon (family Chamaeleonidae; Chamaeleo calyptratus) reared at a zoo in Ishikawa, Japan

Author

EKAWASTI, Fitrine, KITAGAWA, Kazuya, DOMAE, Hiroshi, WARDHANA, April Hari, NAGASAWA, Junki, SHIBAHARA, Tomoyuki, TOKORO, Masaharu, SASAI, Kazumi, and MATSUBAYASHI, Makoto

Subjects
Feces, Isospora, Japan, parasitic diseases, Oocysts, Animals, Wildlife Science, Lizards, Note, oocyst, veiled chameleon, Phylogeny
Abstract

Oocysts of Isospora sp. were detected in the feces of a veiled chameleon (family Chamaeleonidae; Chamaeleo calyptratus) kept at a zoo in Ishikawa, Japan. Phylogenetic analysis placed the sequence in the cluster of Isospora spp. isolated from reptiles. Based on a comparison of morphological data of ten previously reported Isospora species from the Chamaeleonidae family, this isolate was morphologically similar to I. jaracimrmani, which has been considered to be a virulent species. This case study suggests the possibility that species of Isospora might not always cause disease because the animal that shed these oocysts showed no symptoms for more than two months.

Published
2021

28. Prevalence of Enteric Bacteria Pathogens among HIV Infected and Uninfected Children in Dandora, Kenya

Author

Andrew Nyerere, Elizabeth Jemaiyo Matey, Ichimura Hiroshi, Tokoro Masaharu, Willie Sang, and Samya Said Rashid

Subjects
Hiv infected, Enteric bacteria, General Medicine, Biology, Virology
Abstract

Background: Diarrhoea is the second disease killer after respiratory diseases in children. Globally, there are nearly 1.7 billion cases of diarrheal disease every year. In developing countries, enteric bacterial pathogens are most common causes of morbidity and mortality in children especially under 5 years. Most of the studies done on enteric bacteria pathogens and HIV co-infection have focused on the children less than 5 years of age but not above. Objective: This study aimed at evaluating the distribution of common circulating enteric bacterial pathogens; Escherichia (E).coli, Shigella, and Salmonella among HIV infected (n=79) and uninfected (n=78) children aged 5-12 years from Dandora slums of Nairobi. Methods: This was analytic cross-sectional study of HIV positive children enrolled at Nyumbani Lea Toto HIV/AIDS outreach program in Dandora, while HIV negative are children from same area (preferably sibling). Stool samples were collected from consenting participants and sent to Microbiology laboratory in Kenya Medical Research institute for processing. The samples were cultured using differential media for enteric bacteria. Suspected isolates were further identified using conventional biochemical methods and serology. Multiplex PCR was done on E. coli isolates to detect virulence factors responsible for different E. coli pathotypes. Results: The overall prevalence of pathogenic Escherichia coli, Shigella and Salmonella was 44 (28%), 31 (19.7%) and 0 (0.0%) respectively. Enteroaggregative E.coli (43.2%) was the main E. coli pathotypes observed. Distribution of pathogenic E. coli in HIV infected and uninfected was 12.7% and 15.3%, respectively (p = 0.30), while that of Shigella was 6.4% and 13.4% (p = 0.03). Conclusion: From this study HIV infected children had less infestation of Shigella species as compare to HIV uninfected children, which could be due to constant treatment for any infections thus interferes with bacteria grow.

Published
2019
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32. Antibacterial Activity in Iodine-coated Implants Under Conditions of Iodine Loss: Study in a Rat Model Plus In Vitro Analysis.

Author

Ken Ueoka, Tamon Kabata, Masaharu Tokoro, Yoshitomo Kajino, Daisuke Inoue, Tomoharu Takagi, Takaaki Ohmori, Junya Yoshitani, Takuro Ueno, Yuki Yamamuro, Atsushi Taninaka, Hiroyuki Tsuchiya, Ueoka, Ken, Kabata, Tamon, Tokoro, Masaharu, Kajino, Yoshitomo, Inoue, Daisuke, Takagi, Tomoharu, Ohmori, Takaaki, and Yoshitani, Junya

Subjects
ANIMAL disease models, GRAM-positive bacteria, IODINE, BACTERIAL colonies, RATS, JOINT infections, STAPHYLOCOCCAL disease prevention, INFECTION prevention, PROSTHETICS, IN vitro studies, BIOLOGICAL models, BIOFILMS, METHICILLIN-resistant staphylococcus aureus, BIOMEDICAL materials, INFECTION, STAPHYLOCOCCAL diseases, PSEUDOMONAS diseases, PSEUDOMONAS, TITANIUM, COMPLICATIONS of prosthesis, ANTIBIOTICS, ANIMALS, PHARMACODYNAMICS
Abstract

Background: We developed iodine-coated titanium implants to suppress microbial activity and prevent periprosthetic joint infection (PJI); their efficacy was demonstrated in animal and in vitro models. The iodine content in iodine-coated implants naturally decreases in vivo. However, to our knowledge, the effect of reduced iodine content on the implant's antimicrobial activity has not been evaluated to date.Questions/purposes: (1) How much does the iodine content on the implant surface decrease after 4 and 8 weeks in vivo in a rat model? (2) What effect does the reduced iodine content have on the antimicrobial effect of the implant against multiple bacteria in an in vitro model?Methods: This experiment was performed in two parts: an in vivo experiment to determine attenuation of iodine levels over time in rats, and an in vitro experiment in which we sought to assess whether the reduced iodine content observed in the in vivo experiment was still sufficient to deliver antimicrobial activity against common pathogens seen in PJI. For the in vivo experiment, three types of titanium alloy washers were implanted in rats: untreated (Ti), surface-anodized to produce an oxide film (Ti-O), and with an iodine layer on the oxidation film (Ti-I). The attenuation of iodine levels in rats was measured over time using inductively coupled plasma-mass spectrometry. Herein, only the Ti-I washer was used, with five implanted in each rat that were removed after 4 or 8 weeks. For the 4- and 8-week models, two rats and 15 washers were used. For the in vitro study, to determine the antibacterial effect, three types of washers (Ti, Ti-O, and Ti-I) (nine washers in total) were implanted in each rat. Then, the washers were removed and the antibacterial effect of each washer was examined on multiple bacterial species using the spread plate method and fluorescence microscopy. For the spread plate method, six rats were used, and five rats were used for the observation using fluorescence microscopy; further, 4- and 8-week models were made for each method. Thus, a total of 22 rats and 198 washers were used. Live and dead bacteria in the biofilm were stained, and the biofilm coverage percentage for quantitative analysis was determined using fluorescence microscopy in a nonblinded manner. Ti-I was used as the experimental group, and Ti and Ti-O were used as control groups. The total number of rats and washers used throughout this study was 24 and 213, respectively.Results: Iodine content in rats implanted with Ti-I samples decreased to 72% and 65% after the in vivo period of 4 and 8 weeks, respectively (p = 0.001 and p < 0.001, respectively). In the in vitro experiment, the Ti-I implants demonstrated a stronger antimicrobial activity than Ti and Ti-O implants in the 4- and 8-week models. Both the median number of bacterial colonies and the median biofilm coverage percentage with live bacteria on Ti-I were lower than those on Ti or Ti-O implants for each bacterial species in the 4- and 8-week models. There was no difference in the median biofilm coverage percentage of dead bacteria. In the 8-week model, the antibacterial activity using the spread plate method had median (interquartile range) numbers of bacteria on the Ti, Ti-O, and Ti-I implants of 112 (104 to 165) × 105, 147 (111 to 162) × 105, and 55 (37 to 67) × 105 of methicillin-sensitive Staphylococcus aureus (Ti-I versus Ti, p = 0.026; Ti-I versus Ti-O, p = 0.009); 71 (39 to 111) × 105, 50 (44 to 62) × 105, and 26 (9 to 31)× 105 CFU of methicillin-resistant S. aureus (Ti-I versus Ti, p = 0.026; Ti-I versus Ti-O, p = 0.034); and 77 (74 to 83) × 106, 111 (95 to 117) × 106, and 30 (21 to 45) × 106 CFU of Pseudomonas aeruginosa (Ti-I versus Ti, p = 0.004; Ti-I versus Ti-O, p = 0.009). Despite the decrease in the iodine content of Ti-I after 8 weeks, it demonstrated better antibacterial activity against all tested bacteria than the Ti and Ti-O implants.Conclusion: Iodine-coated implants retained their iodine content and antibacterial activity against methicillin-sensitive S. aureus, methicillin-resistant S. aureus, and P. aeruginosa for 8 weeks in vivo in rats. To evaluate the longer-lasting antibacterial efficacy, further research using larger infected animal PJI models with implants in the joints of both males and females is desirable.Clinical Relevance: Iodine-coated titanium implants displayed an antibacterial activity for 8 weeks in rats in vivo. Although the findings in a rat model do not guarantee efficacy in humans, they represent an important step toward clinical application. [ABSTRACT FROM AUTHOR]

Published
2021
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33. Detections of gastrointestinal parasites, including Giardia intestinalis and Cryptosporidium spp., in cattle of Banten province, Indonesia

Author

Sawitri, Dyah Haryuningtyas, primary, Wardhana, April Hari, additional, Martindah, Eny, additional, Ekawasti, Fitrine, additional, Dewi, Dias Aprita, additional, Utomo, Bambang Ngaji, additional, Shibahara, Tomoyuki, additional, Kusumoto, Masahiro, additional, Tokoro, Masaharu, additional, Sasai, Kazumi, additional, and Matsubayashi, Makoto, additional

Published
2019
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35. Adenovirus-prime and baculovirus-boost heterologous immunization achieves sterile protection against malaria sporozoite challenge in a murine model

Author

Yoshida, Kunitaka, primary, Iyori, Mitsuhiro, additional, Blagborough, Andrew M., additional, Salman, Ahmed M., additional, Dulal, Pawan, additional, Sala, Katarzyna A., additional, Yamamoto, Daisuke S., additional, Khan, Shahid M., additional, Janse, Chris J., additional, Biswas, Sumi, additional, Yoshii, Tatsuya, additional, Yusuf, Yenni, additional, Tokoro, Masaharu, additional, Hill, Adrian V. S., additional, and Yoshida, Shigeto, additional

Published
2018
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37. Ancylostoma ceylanicum hookworm infection in Japanese traveler who presented chronic diarrhea after return from Lao People's Democratic Republic

Author

Kaya, Daisuke, primary, Yoshikawa, Masahide, additional, Nakatani, Toshiya, additional, Tomo-oka, Fumimasa, additional, Fujimoto, Yuki, additional, Ishida, Koji, additional, Fujinaga, Yukihisa, additional, Aihara, Yosuke, additional, Nagamatsu, Shinsaku, additional, Matsuo, Eijo, additional, Tokoro, Masaharu, additional, Ouji, Yukiteru, additional, and Kikuchi, Eiryo, additional

Published
2016
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39. Impact of HIV Infection and Anti-Retroviral Therapy on the Immune Profile of and Microbial Translocation in HIV-Infected Children in Vietnam

Author

Bi, Xiuqiong, primary, Ishizaki, Azumi, additional, Nguyen, Lam, additional, Matsuda, Kazunori, additional, Pham, Hung, additional, Phan, Chung, additional, Ogata, Kiyohito, additional, Giang, Thuy, additional, Phung, Thuy, additional, Nguyen, Tuyen, additional, Tokoro, Masaharu, additional, Pham, An, additional, Khu, Dung, additional, and Ichimura, Hiroshi, additional

Published
2016
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42. Possible pathogenicity of commensal Entamoeba hartmannirevealed by molecular screening of healthy school children in Indonesia

Author

Matsumura, Takahiro, Hendarto, Joko, Mizuno, Tetsushi, Syafruddin, Din, Yoshikawa, Hisao, Matsubayashi, Makoto, Nishimura, Taro, and Tokoro, Masaharu

Abstract

Although parasites are still endemic in developing areas, residents in those regions seem not to be affected by the presence of intestinal protozoans. This study aimed to investigate whether pathogenic and commensal protozoans are the causal agents of diarrhea via a school-based cross-sectional survey conducted in Indonesia, in September 2016. Molecular screening for intestinal protozoans in collected 144 stool samples from healthy students (age range 7–15 years) was carried out. The prevalence of protozoan parasites was as follows: Giardia intestinalis(56.3%), Entamoeba histolytica(0%), E. dispar(6.9%), E. moshkovskii(0%), E. hartmanni(31.3%), and E. coli(44.4%). Observational evaluation of stool conditions using the Bristol stool chart confirmed the loose stool rate (33.3–90.9%) in each age group. Logistic regression analysis of protozoan infection or colonization for loose stool (mild to severe diarrhea) as an outcome revealed no significant findings in examined protozoans including pathogenic G. intestinalisinfection [adjusted odds ratio (AOR) 0.78, 95% confidence interval (CI) 0.36–1.67], except in E. hartmannicolonization (AOR 2.81, 95% CI 1.1–3.7, P= 0.026). The molecular survey of intestinal protozoans targeting healthy population with their stool form evaluation could address the pathogenicity of those parasites appropriately. In comparatively higher-age children at least 7 years of age or greater in the endemic area, G. intestinaliscould regard commensal, while E. hartmanniseems to possess a certain pathogenicity as a causal agent of mild diarrhea.

Published
2019
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46. Bowman’s layer encystment in cases of persistent Acanthamoeba keratitis

Author

Yokogawa,Hideaki, Kobayashi,Akira, Yamazaki,Natsuko, Ishibashi,Yasuhisa, Oikawa,Yosaburo, Tokoro,Masaharu, Sugiyama,Kazuhisa, Yokogawa,Hideaki, Kobayashi,Akira, Yamazaki,Natsuko, Ishibashi,Yasuhisa, Oikawa,Yosaburo, Tokoro,Masaharu, and Sugiyama,Kazuhisa

Abstract

Hideaki Yokogawa,1 Akira Kobayashi,1 Natsuko Yamazaki,1 Yasuhisa Ishibashi,2 Yosaburo Oikawa,3 Masaharu Tokoro,4 Kazuhisa Sugiyama11Department of Ophthalmology, Kanazawa University Graduate School of Medical Science, Kanazawa, 2Department of Ophthalmology, East Washinomiya Hospital, Kuki, 3Department of Medical Zoology, Kanazawa Medical University, Kahoku, 4Department of Parasitology, Kanazawa University Graduate School of Medical Science, Kanazawa, JapanBackground: The purpose of this study was to report Acanthamoeba encystment in Bowman’s layer in Japanese cases of persistent Acanthamoeba keratitis (AK).Methods: Laser confocal microscopic images of the cornea were obtained in vivo from 18 consecutive eyes from 17 confirmed AK patients. Retrospectively, 14 cases treated over 4 months were categorized as a nonpersistent group and three cases that required prolonged therapy for more than 6 months were categorized as a persistent group. Clinical outcomes based on final best-corrected visual acuity were retrospectively analyzed, and selected confocal images were evaluated qualitatively for abnormal findings.Results: The final best-corrected visual acuity was significantly lower (P < 0.01) for patients in the persistent group compared with that in the nonpersistent group. At the initial visit, in vivo confocal microscopy demonstrated Acanthamoeba cysts exclusively in the epithelial layer in both the nonpersistent group (80%) and the persistent group (100%). At a subsequent follow-up visit, numerous Acanthamoeba cysts were observed in the epithelial cell layer and in Bowman’s layer in all patients with persistent AK, but Acanthamoeba cysts were undetectable in all cases with nonpersistent AK tested.Conclusion: Invasion of cysts into Bowman’s layer was characteristically observed in patients with persistence of AK. This finding suggests that invasion of Acanthamoeba cysts into Bowman’s layer may be a useful predictor for a pe

Published
2012

47. Ex vivo laser confocal microscopy findings of cultured Acanthamoeba trophozoites

Author

Yamazaki,Natsuko, Kobayashi,Akira, Yokogawa,Hideaki, Ishibashi,Yasuhisa, Oikawa,Yosaburo, Tokoro,Masaharu, Sugiyama,Kazuhisa, Yamazaki,Natsuko, Kobayashi,Akira, Yokogawa,Hideaki, Ishibashi,Yasuhisa, Oikawa,Yosaburo, Tokoro,Masaharu, and Sugiyama,Kazuhisa

Abstract

Natsuko Yamazaki,1 Akira Kobayashi,1 Hideaki Yokogawa,1 Yasuhisa Ishibashi,2 Yosaburo Oikawa,3 Masaharu Tokoro,4 Kazuhisa Sugiyama11Department of Ophthalmology, Kanazawa University Graduate School of Medical Science, Kanazawa, Japan; 2Department of Ophthalmology, East Washinomiya Hospital, Kuki, Japan; 3Department of Medical Zoology, Kanazawa Medical University, Kahoku, Japan; 4Department of Parasitology, Kanazawa University Graduate School of Medical Science, Kanazawa, JapanPurpose: The purpose of the current study was to investigate ex vivo laser confocal microscopic findings of cultured Acanthamoeba trophozoites obtained from Acanthamoeba keratitis patients.Methods: Eight cultured samples of Acanthamoeba trophozoites from eight eyes of seven patients (mean age, 26.9 years; age range, 18–52 years) were used. Seven samples were from corneal scrapings of Acanthamoeba keratitis patients and one sample was from the solution in a soft contact lens case. Ex vivo laser confocal microscopy was performed to qualitatively evaluate the shape and degree of light reflection of the living Acanthamoeba trophozoites.Results: Ex vivo laser confocal microscopy demonstrated highly reflective, high-contrast Acanthamoeba trophozoites with no walls (mean size, 25.4 µm; range, 17.1–58.5 µm). The shapes of the trophozoites were highly pleomorphic, and some showed characteristic acanthopodia by laser confocal microscopy.Conclusion: Ex vivo laser confocal microscopy was effective in demonstrating cultured Acanthamoeba trophozoites of various shapes and sizes. The observations of the current study may be helpful when similar structures are identified under in vivo conditions.Keywords: Acanthamoeba, trophozoite, laser confocal microscopy

Published
2012

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