Fukumi Nakamura-Uchiyama

In vitro differentiation of mouse embryonic stem cells into inner ear hair cell-like cells using stromal cell conditioned medium

Hearing loss is mainly caused by loss of sensory hair cells (HCs) in the organ of Corti or cochlea. Although embryonic stem (ES) cells are a promising source for cell therapy, little is known about the efficient generation of HC-like cells from ES cells. In the present study, we developed a single-medium culture method for growing embryoid bodies (EBs), in which conditioned medium (CM) from cultures of ST2 stromal cells (ST2-CM) was used for 14-day cultures of 4-day EBs. At the end of the 14-day cultures, up to 20% of the cells in EB outgrowths expressed HC-related markers, including Math1 (also known as Atoh1), myosin6, myosin7a, calretinin, α9AchR and Brn3c (also known as Pou4f3), and also showed formation of stereocilia-like structures. Further, we found that these cells were incorporated into the developing inner ear after transplantation into chick embryos. The present inner ear HC induction method using ST2-CM (HIST2 method) is quite simple and highly efficient to obtain ES-derived HC-like cells with a relatively short cultivation time.

Canonical Wnts, specifically Wnt-10b, show ability to maintain dermal papilla cells

Although Wnts are expressed in hair follicles (HFs) and considered to be crucial for maintaining dermal papilla (DP) cells, the functional differences among them remain largely unknown. In the present study, we investigated the effects of Wnts (Wnt-3a, 5a, 10b, 11) on the proliferation of mouse-derived primary DP cells in vitro as well as their trichogenesis-promoting ability using an in vivo skin reconstitution protocol. Wnt-10b promoted cell proliferation and trichogenesis, while Wnt-3a showed those abilities to a limited extent, and Wnt-5a and 11 had no effects. Furthermore, we investigated the effects of these Wnts on cultured DP cells obtained from versican-GFP transgenic mice and found that Wnt-10b had a potent ability to sustain their GFP-positivity. These results suggest that canonical Wnts, specifically Wnt-10b, play important roles in the maintenance of DP cells and trichogenesis.

Severe murine typhus with shock and acute respiratory failure in a Japanese traveler after returning from Thailand.

We treated a case of severe murine typhus in a Japanese traveler after returning from Thailand. Although the disease is typically self-limited or mild, the patient showed shock and multiple organ failure including acute respiratory distress syndrome. Then the patient fully recovered following intensive care and administration of antirickettsial medicines.

JAID/JSC Guidelines for the Treatment of Respiratory Infectious Diseases: The Japanese Association for Infectious Diseases/Japanese Society of Chemotherapy - The JAID/JSC Guide to Clinical Management of Infectious Disease/Guideline-preparing Committee Respiratory Infectious Disease WG

a Center for Infectious Diseases, Nara Medical University, Nara, Japan b Shinrakuen Hospital, Niigata, Japan c Department of International Medicine, Division of Infectious Diseases, Faculty of Medicine, Saga University, Saga, Japan d Department of Infectious Diseases, Yamagata Prefectural Central Hospital, Yamagata, Japan e Department of Infectious Diseases, Keio University School of Medicine, Tokyo, Japan f Department of Pediatrics, Kawasaki Medical School, Okayama, Japan g Department of Respiratory Medicine and Infectious Diseases, Oita University Faculty of Medicine, Oita, Japan h Sapporo Medical Academy, Hokkaido, Japan i Kyorin University, Tokyo, Japan j Department of Pediatrics, Asahikawa Kosei Hospital, Hokkaido, Japan k Division of Respiratory Medicine and Infection Control, Tohoku Pharmaceutical University Hospital, Miyagi, Japan l Department of Respiratory Medicine and Infectious Diseases, Niigata City General Hospital, Niigata, Japan m Infection Control and Prevention Center, Gunma University Hospital, Gunma, Japan n Department of Pathogen, Infection and Immunity, Nara Medical University, Nara, Japan o Department of Respiratory Medicine, National Hospital Organization Okinawa National Hospital, Okinawa, Japan p Department of Laboratory Medicine, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan q Kinki University Hospital, Faculty of Medicine, Osaka, Japan

Partial Maintenance and Long-Term Expansion of Murine Skin Epithelial Stem Cells by Wnt-3a In Vitro

CD49f(+)CD34(+) cells, a skin epithelial stem cell (EpSC)-rich population, were prepared from adult mouse skin and cultured in the presence of Wnt-3a without feeder cells. CD34 expression was retained in about 10% of the cells, which had proliferated about 1,000-fold by day 10, although completely lost by day 14. CD49f(+)CD34(+) cells sorted on day 10 retained canonical Wnt-responsiveness, proliferated markedly in the presence of Wnt-3a, maintained undifferentiated epithelial cell marker expression, and promoted hair follicle development in vivo. Those were subjected to a second 10-day culture with Wnt-3a and sorted, and then the same procedures were repeated a total of 15 times. CD49f(+)CD34(+) cells obtained from each of those cultures retained the same EpSC characteristics as the original cells. CD34(+) and CD34(-) cells were found to produce Wnt-3a and Wnt/β-catenin inhibitors, respectively. CD34(+) cells resided as small cellular clusters surrounded by a large amount of CD34(-) cells. Furthermore, we found that exogenous Wnt-3a delayed the conversion of CD34(+) cells to CD34(-) cells and induced CD34(-) cells to suppress the production of Wnt/β-catenin inhibitors, likely leading to generation of a microenvironment favorable for maintaining EpSCs. Our results suggest the possibility of partial long-term maintenance of EpSCs in vitro by Wnt-3a.

Subjective adverse reactions to metronidazole in patients with amebiasis.

Subjective adverse reactions to metronidazole were analyzed in 111 patients with amebiasis. Metronidazole was administered to 36 patients at a daily dose of 2250 mg and 75 patients at daily doses lower than 2250 mg. The reactions reported included nausea without vomiting in 11 (9.9%) patients, nausea with vomiting in 2 (1.8%), dysgeusia in 2 (1.8%), diarrhea in 1 (0.9%), headache in 1 (0.9%), numbness in 1 (0.9%), dizziness in 1 (0.9%), urticaria in 1 (0.9%), exanthema in 1 (0.9%), and discomfort in 1 (0.9%). Nausea was reported by 28% (10/36) of the patients receiving metronidazole at a daily dose of 2250 mg and 4% (3/75) of the patients receiving lower daily doses. The duration of the metronidazole administration in days was not associated with the appearance of nausea. No life-threatening adverse reactions were identified, and good clinical therapeutic effects were observed in 96% (107/111) of the patients. While metronidazole appears to be a safe anti-protozoal agent for patients with amebiasis, our results indicate that a daily metronidazole dose of 2250 mg is excessive for amebiasis, as it often induces nausea.

Therapeutic effect of praziquantel against Taeniasis asiatica.

Eight Japanese adult patients infected with Taenia asiatica were treated with a single 600 mg dose of praziquantel. The patients body weights ranged from 47 to 87 kg (mean 67.1±12.7 kg). All patients expelled the strobila after taking praziquantel, and all of them were free from proglottids the day after praziquantel administration, hence all patients were considered to be cured. No side effects due to praziquantel were noted. Although the number of patients is small, our results indicate that praziquantel is a drug of choice for the treatment of taeniasis asiatica and that a single dose of 7-13 mg/kg (9.3±1.9 mg/kg) is effective.

Effects of Wnt-10b on proliferation and differentiation of murine melanoma cells

In spite of the strong expression of Wnt-10b in melanomas, its role in melanoma cells has not been elucidated. In the present study, the biological effects of Wnt-10b on murine B16F10 (B16) melanoma cells were investigated using conditioned medium from Wnt-10b-producing COS cells (Wnt-CM). After 2 days of culture in the presence of Wnt-CM, proliferation of B16 melanoma cells was inhibited, whereas tyrosinase activity was increased. An inxa0vitro wound healing assay demonstrated that migration of melanoma cells to the wound area was inhibited with the addition of Wnt-CM. Furthermore, evaluation of cellular senescence revealed prominent induction of SA-β-gal-positive senescent cells in cultures with Wnt-CM. Finally, the growth of B16 melanoma cell aggregates in collagen 3D-gel cultures was markedly suppressed in the presence of Wnt-CM. These results suggest that Wnt-10b represses tumor cell properties, such as proliferation and migration of B16 melanoma cells, driving them toward a more differentiated state along a melanocyte lineage.

Ancylostoma ceylanicum , novel etiological agent for traveler’s diarrhea—report of four Japanese patients who returned from Southeast Asia and Papua New Guinea

BackgroundCountries in the Southeast Asia region have a high prevalence of soil-transmitted helminth, such as roundworm, whipworm, and hookworms [Ancylostoma duodenale, Necator americanus, Ancylostoma ceylanicum]. Recent molecular-based surveys have revealed that A. ceylanicum, a zoonotic hookworm, is likely the second most prevalent hookworm species infecting humans in that part of the world, while others have noted that this infection is an emerging public health risk not only for indigenous people but also for visitors from other countries.Case presentationWe recently encountered four cases of A. ceylanicum infection in Japanese individuals who returned from Southeast Asia and Papua New Guinea. Case 1 was a 25-year-old male who stayed in a rainforest in Malaysia for 4xa0weeks, where he developed abdominal pain and diarrhea in the third week. Eleven adult worms (five males, six females) were expelled after treatment with pyrantel pamoate and identified as A. ceylanicum based on morphological characteristics and DNA sequences of the mitochondrial cytochrome c oxidase subunit 1 (cox1) gene. Case 2 was a 26-year-old male who spent 2xa0years as an overseas cooperation volunteer for agriculture in Papua New Guinea. He did not note any symptoms at that time, though eggs were detected in feces samples at a medical check-up examination after returning. Although collection of adult worms was unsuccessful, DNA analysis of the eggs for cox1 and the ribosomal internal transcribed spacer (ITS)-1 and ITS-2 genes demonstrated that they were A. ceylanicum. Case 3 was a 47-year-old male who spent 1xa0month in a rural village in Lao People’s Democratic Republic and began suffering from watery diarrhea from the third week. A total of nine adult worms (three males, six females) were collected by endoscopic procedures and following treatment with pyrantel pamoate. Morphological examination and molecular analyses of the cox1 gene showed that they were A. ceylanicum. Case 4 was a 27-year-old male who participated in group travel to India for 5xa0days. Three weeks after returning, he developed abdominal pain and diarrhea. Hookworm eggs were found in feces samples and developed into larvae in culture, which were identified as A. ceylanicum based on molecular analysis of the cox1 gene. Eosinophilia was observed in all of the cases prior to treatment.ConclusionsA. ceylanicum should be recognized as an important etiologic pathogen of hookworm diseases in travelers to countries in the Southeast Asia and West Pacific Ocean regions.

Pseudo-SLE by human immunodeficiency virus infection

A 61-year-old woman was admitted for long-lasting fever and recurrent opportunistic infections during the treatment of SLE. She had been diagnosed as SLE and type-IV nephritis based on a renal biopsy and serological findings. A colonoscopy and liver biopsy revealed disseminated Mycobacterium avium complex infection. Human immunodeficiency virus (HIV) infection status was then examined and found to be positive. From the clinical course, the first symptoms were inferred to have been those of HIV infection.