Displaying publications 21 - 40 of 40 in total

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  1. Yoshida N, Hirose R, Watanabe M, Yamazaki M, Hashimoto S, Matsubara S, et al.
    JGH Open, 2021 Jan;5(1):160-162.
    PMID: 33490630 DOI: 10.1002/jgh3.12435
    COVID-19 rarely causes lower gastrointestinal bleeding even though its RNA has been detected in patient's stool. Urgent colonoscopy in a COVID-19 patient with massive bloody stool requires various procedural and equipment considerations. Here, we present a case of colonoscopic hemostasis of a cecal hemorrhagic ulceration in a patient on heparin for COVID-19 coagulopathy. We also share various management methods for the prevention of COVID-19 contamination. A 71-year-old man was diagnosed with COVID-19 pneumonia and subsequently underwent hemodiafiltration. Heparin was initiated for COVID-19 coagulopathy. At day 42, the patient experienced 2000 mL of bloody stool. An operator performed urgent colonoscopy with three assistants in a negative-pressure room with full personal protective equipment. A hemorrhagic ulceration was detected at the cecum, and endoscopic hemostasis was performed. Immunohistochemistry was positive for cytomegalovirus. Postprocedure, the endoscopic systems were thoroughly cleaned, and specific measures for endoscope reprocessing and disinfection were performed to prevent contamination with COVID-19.
  2. Kolandaiveloo V, Kalaiselvam R, Fong MWC, Mustapa MS, Souce RM, Sugnaseelan S, et al.
    J Vet Med Sci, 2020 Apr 15;82(4):497-502.
    PMID: 32101821 DOI: 10.1292/jvms.19-0477
    Chelonian exhibit temperature dependent sex determination, and ex situ incubation of eggs in conservation hatcheries may render a gender bias. The gender of juvenile Painted terrapins (Batagur borneoensis) produced at a conservation hatchery in Malaysia was determined by endoscopy of the gonads. Circulating reproductive hormones (testosterone, progesterone and estradiol) were profiled for 31 juveniles and nine captive-reared non-breeding adult terrapins. Endoscopy revealed a gender bias of 96.8% (30/31) females. Testosterone levels in the juvenile females (2.49 ± 1.29) were significantly lower than that of the adult females (12.20 ± 4.29), and lower than values in the juvenile male (9.36) and adult males (27.60, 35.62). The progesterone levels in the juvenile females (107.12 ± 68.68) were significantly higher than that of the adult females (51.13 ± 24.67), but lower than values in the juvenile male (33.27) and adult males (3.43, 8.51). Estrogen levels were significantly lower in the juvenile females (1.57 ± 1.35) compared to the adult females (77.46 ± 53.45). Negative correlations were observed between levels of progesterone and testosterone, and progesterone and estrogen. A positive correlation was noted between estrogen and testosterone. The present study constitutes the first attempt to determine the gender and reproductive hormone profiles of juvenile Painted terrapins produced by ex situ incubation, and captive non-breeding adults. Endoscopy of the gonads is a useful techniques for gender determination among juvenile turtles, while the use of testosterone as a gender biomarker warrants further investigation.
  3. Nasiru Wana M, Mohd Moklas MA, Watanabe M, Nordin N, Zasmy Unyah N, Alhassan Abdullahi S, et al.
    PMID: 32635389 DOI: 10.3390/ijerph17134809
    Toxoplasmosis is a disease caused by the protozoan parasite Toxoplasma gondii (T. gondii). Human toxoplasmosis seroprevalence in Malaysia has increased since it was first reported in 1973 as shown in previous reviews of 1991 and 2007. However, over a decade since the last review, comprehensive data on toxoplasmosis in Malaysia is lacking. This work aimed at reviewing articles on toxoplasmosis research in Malaysia in order to identify the research gaps, create public awareness, and efforts made so far and proffer management options on the disease. The present review examines the available published research articles from 2008 to 2018 related to toxoplasmosis research conducted in Malaysia. The articles reviewed were retrieved from nine credible databases such as Web of Science, Google Scholar, ScienceDirect, PubMed, Scopus, Springer, Wiley online library, Ovid, and Cochrane using the keywords; Malaysia, toxoplasmosis, Toxoplasma gondii, toxoplasma encephalitis, seroprevalence, human immunodeficiency virus (HIV) patients, pregnant women, genotype strain, anti-toxoplasma antibodies, felines, and vaccine. The data highlighted seropositive cases from healthy community members in Pangkor Island (59.7%) and among migrant workers (57.4%) at alarming rates, as well as 42.5% in pregnant women. Data on animal seroprevalence were limited and there was no information on cats as the definitive host. Genetic characterization of Toxoplasma gondii from HIV patients; pregnant women, and domestic cats is lacking. This present review on toxoplasmosis is beneficial to researchers, health workers, animal health professionals, and policymakers. Therefore, attention is required to educate and enlighten health workers and the general public about the risk factors associated with T. gondii infection in Malaysia.
  4. Watanabe M, Sadiq MB, Mulop NIA, Mohammed K, Rani PAM, Fong LS, et al.
    Korean J Parasitol, 2020 Oct;58(5):487-492.
    PMID: 33202500 DOI: 10.3347/kjp.2020.58.5.487
    Toxoplasmosis is caused by an obligate intracellular protozoan parasite; Toxoplasma gondii, which is one of the most important zoonotic parasite worldwide. In dogs, the sexual reproductive cycle of T. gondii is lacking, and the animals are not widely consumed as food, but they are vital in the mechanical transmission of the parasite. However, there is no present data on the exposure of stray dogs to T. gondii in Malaysia. The objective of this serological survey was to determine the prevalence of T. gondii antibodies (IgG) and associated factors in stray dogs in East and West Malaysia. Antibodies to T. gondii were determined in serum samples from 222 stray dogs from 6 different states in East and West Malaysia (Peninsular Malaysia) using an Indirect ELISA. The seroprevalence for T. gondii was 23.4% (Confidence interval: CI 17.8-29.2%). Stray dogs from Selangor and Kuala Lumpur had the highest seroprevalence (32.4%; CI 13.2-45.5%) and lowest in those from Penang and Kedah (12.5%; CI 1.3-23.5%). Gender and breed were not associated with T. gondii seropositivity. However, adult dogs were more likely to be seropositive for T. gondii (OR=2.89; CI 1.1-7.7) compared with younger dogs. These results revealed that T. gondii is prevalent in stray dogs in the studied areas in Malaysia, and indicative of the level of environmental contamination of this parasite especially in urban areas.
  5. Dantas-Torres F, Ketzis J, Mihalca AD, Baneth G, Otranto D, Tort GP, et al.
    Vet Parasitol, 2020 Jul;283:109167.
    PMID: 32580071 DOI: 10.1016/j.vetpar.2020.109167
    The Tropical Council for Companion Animal Parasites Ltd. (TroCCAP) is a not-for-profit organisation whose mission is to independently inform, guide and make best-practice recommendations for the diagnosis, treatment and control of companion animal parasites in the tropics and sub-tropics, with the aim of protecting animal and human health. In line with this primary mission, TroCCAP recently developed guidelines for the diagnosis, treatment and control of feline and canine parasites in the tropics. The development of these guidelines required unique and complex considerations to be addressed, often inapplicable to developed nations. Much of the tropics encompass middle-to-low income countries in which poor standards of environmental hygiene and large populations of stray dogs and cats coexist. In these regions, a range of parasites pose a high risk to companion animals, which ultimately may place their owners at risk of acquiring parasitic zoonoses. These considerations led to the development of unique recommendations with regard, for example, to deworming and endoparasite testing intervals for the control of both global and 'region-specific' parasites in the tropics. Moreover, the 'off-' or 'extra'-label use of drugs for the treatment and control of parasitic infections is common practice in many tropical countries and many generic products lack manufacturers' information on efficacy, safety, and quality control. Recommendations and advice concerning the use of such drugs and protocols are also addressed in these guidelines. The formation of these guidelines is an important first step towards improving the education of veterinarians specifically regarding best-practice for the diagnosis, treatment and control of canine and feline parasites in the tropics.
  6. Ran Z, Wu K, Matsuoka K, Jeen YT, Wei SC, Ahuja V, et al.
    J Gastroenterol Hepatol, 2021 Mar;36(3):637-645.
    PMID: 32672839 DOI: 10.1111/jgh.15185
    Inflammatory bowel disease (IBD) has increased in incidence and prevalence in Asian countries since the end of the 20th century. Moreover, differences in the cause, phenotypes, and natural history of IBD between the East and West have been recognized. Therefore, the Asian Organization for Crohn's and Colitis and the Asia Pacific Association of Gastroenterology have established recommendations on medical management of IBD in Asia. Initially, the committee members drafted 40 recommendations, which were then assessed according to Grading of Recommendations Assessment, Development and Evaluation. Eight statements were rejected as this indicated that consensus had not been reached. The recommendations encompass pretreatment evaluation; medical management of active IBD; medical management of IBD in remission; management of IBD during the periconception period and pregnancy; surveillance strategies for colitis-associated cancer; monitoring side effects of thiopurines and methotrexate; and infections in IBD.
  7. Saitsu H, Watanabe M, Akita T, Ohba C, Sugai K, Ong WP, et al.
    Sci Rep, 2016 07 20;6:30072.
    PMID: 27436767 DOI: 10.1038/srep30072
    Epilepsy of infancy with migrating focal seizures (EIMFS) is one of the early-onset epileptic syndromes characterized by migrating polymorphous focal seizures. Whole exome sequencing (WES) in ten sporadic and one familial case of EIMFS revealed compound heterozygous SLC12A5 (encoding the neuronal K(+)-Cl(-) co-transporter KCC2) mutations in two families: c.279 + 1G > C causing skipping of exon 3 in the transcript (p.E50_Q93del) and c.572 C >T (p.A191V) in individuals 1 and 2, and c.967T > C (p.S323P) and c.1243 A > G (p.M415V) in individual 3. Another patient (individual 4) with migrating multifocal seizures and compound heterozygous mutations [c.953G > C (p.W318S) and c.2242_2244del (p.S748del)] was identified by searching WES data from 526 patients and SLC12A5-targeted resequencing data from 141 patients with infantile epilepsy. Gramicidin-perforated patch-clamp analysis demonstrated strongly suppressed Cl(-) extrusion function of E50_Q93del and M415V mutants, with mildly impaired function of A191V and S323P mutants. Cell surface expression levels of these KCC2 mutants were similar to wildtype KCC2. Heterologous expression of two KCC2 mutants, mimicking the patient status, produced a significantly greater intracellular Cl(-) level than with wildtype KCC2, but less than without KCC2. These data clearly demonstrated that partially disrupted neuronal Cl(-) extrusion, mediated by two types of differentially impaired KCC2 mutant in an individual, causes EIMFS.
  8. Davis OC, Dickie AC, Mustapa MB, Boyle KA, Browne TJ, Gradwell MA, et al.
    Sci Rep, 2023 Jul 18;13(1):11561.
    PMID: 37464016 DOI: 10.1038/s41598-023-38605-9
    Unmyelinated non-peptidergic nociceptors (NP afferents) arborise in lamina II of the spinal cord and receive GABAergic axoaxonic synapses, which mediate presynaptic inhibition. However, until now the source of this axoaxonic synaptic input was not known. Here we provide evidence that it originates from a population of inhibitory calretinin-expressing interneurons (iCRs), which correspond to lamina II islet cells. The NP afferents can be assigned to 3 functionally distinct classes (NP1-3). NP1 afferents have been implicated in pathological pain states, while NP2 and NP3 afferents also function as pruritoceptors. Our findings suggest that all 3 of these afferent types innervate iCRs and receive axoaxonic synapses from them, providing feedback inhibition of NP input. The iCRs also form axodendritic synapses, and their targets include cells that are themselves innervated by the NP afferents, thus allowing for feedforward inhibition. The iCRs are therefore ideally placed to control the input from non-peptidergic nociceptors and pruritoceptors to other dorsal horn neurons, and thus represent a potential therapeutic target for the treatment of chronic pain and itch.
  9. Davis OC, Dickie AC, Mustapa MB, Boyle KA, Browne TJ, Gradwell MA, et al.
    bioRxiv, 2023 Jun 05.
    PMID: 37333120 DOI: 10.1101/2023.06.01.543241
    Unmyelinated non-peptidergic nociceptors (NP afferents) arborise in lamina II of the spinal cord and receive GABAergic axoaxonic synapses, which mediate presynaptic inhibition. However, until now the source of this axoaxonic synaptic input was not known. Here we provide evidence that it originates from a population of inhibitory calretinin-expressing interneurons (iCRs), which correspond to lamina II islet cells. The NP afferents can be assigned to 3 functionally distinct classes (NP1-3). NP1 afferents have been implicated in pathological pain states, while NP2 and NP3 afferents also function as pruritoceptors. Our findings suggest that all 3 of these afferent types innervate iCRs and receive axoaxonic synapses from them, providing feedback inhibition of NP input. The iCRs also form axodendritic synapses, and their targets include cells that are themselves innervated by the NP afferents, thus allowing for feedforward inhibition. The iCRs are therefore ideally placed to control the input from non-peptidergic nociceptors and pruritoceptors to other dorsal horn neurons, and thus represent a potential therapeutic target for the treatment of chronic pain and itch.
  10. Nguyen VL, Colella V, Greco G, Fang F, Nurcahyo W, Hadi UK, et al.
    Parasit Vectors, 2020 Aug 15;13(1):420.
    PMID: 32799914 DOI: 10.1186/s13071-020-04288-8
    BACKGROUND: Ticks and fleas are considered amongst the most important arthropod vectors of medical and veterinary concern due to their ability to transmit pathogens to a range of animal species including dogs, cats and humans. By sharing a common environment with humans, companion animal-associated parasitic arthropods may potentially transmit zoonotic vector-borne pathogens (VBPs). This study aimed to molecularly detect pathogens from ticks and fleas from companion dogs and cats in East and Southeast Asia.

    METHODS: A total of 392 ticks and 248 fleas were collected from 401 infested animals (i.e. 271 dogs and 130 cats) from China, Taiwan, Indonesia, Malaysia, Singapore, Thailand, the Philippines and Vietnam, and molecularly screened for the presence of pathogens. Ticks were tested for Rickettsia spp., Anaplasma spp., Ehrlichia spp., Babesia spp. and Hepatozoon spp. while fleas were screened for the presence of Rickettsia spp. and Bartonella spp.

    RESULT: Of the 392 ticks tested, 37 (9.4%) scored positive for at least one pathogen with Hepatozoon canis being the most prevalent (5.4%), followed by Ehrlichia canis (1.8%), Babesia vogeli (1%), Anaplasma platys (0.8%) and Rickettsia spp. (1%) [including Rickettsia sp. (0.5%), Rickettsia asembonensis (0.3%) and Rickettsia felis (0.3%)]. Out of 248 fleas tested, 106 (42.7%) were harboring at least one pathogen with R. felis being the most common (19.4%), followed by Bartonella spp. (16.5%), Rickettsia asembonensis (10.9%) and "Candidatus Rickettsia senegalensis" (0.4%). Furthermore, 35 Rhipicephalus sanguineus ticks were subjected to phylogenetic analysis, of which 34 ticks belonged to the tropical and only one belonged to the temperate lineage (Rh. sanguineus (sensu stricto)).

    CONCLUSION: Our data reveals the circulation of different VBPs in ticks and fleas of dogs and cats from Asia, including zoonotic agents, which may represent a potential risk to animal and human health.

  11. Park DI, Hisamatsu T, Chen M, Ng SC, Ooi CJ, Wei SC, et al.
    J Gastroenterol Hepatol, 2018 Jan;33(1):30-36.
    PMID: 29024102 DOI: 10.1111/jgh.14018
    Because anti-tumor necrosis factor (anti-TNF) therapy has become increasingly popular in many Asian countries, the risk of developing active tuberculosis (TB) among anti-TNF users may raise serious health problems in this region. Thus, the Asian Organization for Crohn's and Colitis and the Asia Pacific Association of Gastroenterology have developed a set of consensus statements about risk assessment, detection and prevention of latent TB infection, and management of active TB infection in patients with inflammatory bowel disease (IBD) receiving anti-TNF treatment. Twenty-three consensus statements were initially drafted and then discussed by the committee members. The quality of evidence and the strength of recommendations were assessed by using the Grading of Recommendations Assessment, Development, and Evaluation methodology. Web-based consensus voting was performed by 211 IBD specialists from nine Asian countries concerning each statement. A consensus statement was accepted if at least 75% of the participants agreed. Part 2 of the statements comprised three parts: (3) management of latent TB in preparation for anti-TNF therapy, (4) monitoring during anti-TNF therapy, and (5) management of an active TB infection after anti-TNF therapy. These consensus statements will help clinicians optimize patient outcomes by reducing the morbidity and mortality related to TB infections in patients with IBD receiving anti-TNF treatment.
  12. Colella V, Wongnak P, Tsai YL, Nguyen VL, Tan DY, Tong KBY, et al.
    Commun Med (Lond), 2022 Nov 15;2(1):144.
    PMID: 36380151 DOI: 10.1038/s43856-022-00210-8
    BACKGROUND: A recent dramatic surge in pet ownership has been observed across metropolitan areas in Asia. To date, there is a dearth of information on the risk associated with pet ownership for the transmission of parasites on a large scale in Asia, despite this continent giving rise to the largest burden of zoonotic infections worldwide.

    METHODS: We explored the nature and extent of zoonotic internal (endo-) and external (ecto-) parasites and arthropod-borne pathogens in 2381 client-owned dogs and cats living in metropolitan areas of eight countries in East and Southeast Asia using reliable diagnostic tests and then undertook extensive statistical analyses to define predictors of exposure to zoonotic pathogens.

    RESULTS: The estimated ORs for overall parasite infections are 1.35 [95% CIs 1.07;1.71] in young animals and 4.10 [1.50;11.2] in the animal group older than 15 years as compared with adult animals, 0.61 [0.48;0.77] in neutered animals as compared to unneutered animals, 0.36 [0.26;0.50] in animals living in urban areas as compared with rural areas, 1.14 [1.08;1.21] for each 1 °C increase of annual mean temperature which varies from 12.0 to 28.0 °C, and 0.86 [0.78;0.95] for each year of life expectancy which varies from 70.9 to 83.3 years.

    CONCLUSIONS: Here we highlight the influence of human life expectancy and the neutering status of the animals, which reflect increased living standards through access to education and human and veterinary health care, to be both strongly associated with exposure to zoonotic parasites. An integrated approach of local and international authorities to implement and manage educational programs will be crucial for the control of zoonotic infections of companion animals in Asia.

  13. Park DI, Hisamatsu T, Chen M, Ng SC, Ooi CJ, Wei SC, et al.
    J Gastroenterol Hepatol, 2018 Jan;33(1):20-29.
    PMID: 29023903 DOI: 10.1111/jgh.14019
    Because anti-tumor necrosis factor (anti-TNF) therapy has become increasingly popular in many Asian countries, the risk of developing active tuberculosis (TB) among anti-TNF users may raise serious health problems in this region. Thus, the Asian Organization for Crohn's and Colitis and the Asian Pacific Association of Gastroenterology have developed a set of consensus statements about risk assessment, detection, and prevention of latent TB infection and management of active TB infection in patients with inflammatory bowel disease (IBD) receiving anti-TNF treatment. Twenty-three consensus statements were initially drafted and then discussed by the committee members. The quality of evidence and the strength of recommendations were assessed by using the Grading of Recommendations Assessment, Development, and Evaluation methodology. Web-based consensus voting was performed by 211 IBD specialists from nine Asian countries concerning each statement. A consensus statement was accepted if at least 75% of the participants agreed. Part 1 of the statements comprised two parts: (i) risk of TB infection during anti-TNF therapy and (ii) screening for TB infection prior to commencing anti-TNF therapy. These consensus statements will help clinicians optimize patient outcomes by reducing the morbidity and mortality related to TB infections in patients with IBD receiving anti-TNF treatment.
  14. Park DI, Hisamatsu T, Chen M, Ng SC, Ooi CJ, Wei SC, et al.
    Intest Res, 2018 Jan;16(1):17-25.
    PMID: 29422794 DOI: 10.5217/ir.2018.16.1.17
    Because anti-tumor necrosis factor (anti-TNF) therapy has become increasingly popular in many Asian countries, the risk of developing active tuberculosis (TB) among anti-TNF users may raise serious health problems in this region. Thus, the Asian Organization for Crohn's and Colitis and the Asia Pacific Association of Gastroenterology have developed a set of consensus statements about risk assessment, detection and prevention of latent TB infection, and management of active TB infection in patients with inflammatory bowel disease (IBD) receiving anti-TNF treatment. Twenty-three consensus statements were initially drafted and then discussed by the committee members. The quality of evidence and the strength of recommendations were assessed by using the Grading of Recommendations Assessment, Development, and Evaluation methodology. Web-based consensus voting was performed by 211 IBD specialists from 9 Asian countries concerning each statement. A consensus statement was accepted if at least 75% of the participants agreed. Part 2 of the statements comprised 3 parts: management of latent TB in preparation for anti-TNF therapy, monitoring during anti-TNF therapy, and management of an active TB infection after anti-TNF therapy. These consensus statements will help clinicians optimize patient outcomes by reducing the morbidity and mortality related to TB infections in patients with IBD receiving anti-TNF treatment.
  15. Park DI, Hisamatsu T, Chen M, Ng SC, Ooi CJ, Wei SC, et al.
    Intest Res, 2018 Jan;16(1):4-16.
    PMID: 29422793 DOI: 10.5217/ir.2018.16.1.4
    Because anti-tumor necrosis factor (anti-TNF) therapy has become increasingly popular in many Asian countries, the risk of developing active tuberculosis (TB) among anti-TNF users may raise serious health problems in this region. Thus, the Asian Organization for Crohn's and Colitis and the Asia Pacific Association of Gastroenterology have developed a set of consensus statements about risk assessment, detection and prevention of latent TB infection, and management of active TB infection in patients with inflammatory bowel disease (IBD) receiving anti-TNF treatment. Twenty-three consensus statements were initially drafted and then discussed by the committee members. The quality of evidence and the strength of recommendations were assessed by using the Grading of Recommendations Assessment, Development, and Evaluation methodology. Web-based consensus voting was performed by 211 IBD specialists from 9 Asian countries concerning each statement. A consensus statement was accepted if at least 75% of the participants agreed. Part 1 of the statements comprised 2 parts: risk of TB infection Recommendaduring anti-TNF therapy, and screening for TB infection prior to commencing anti-TNF therapy. These consensus statements will help clinicians optimize patient outcomes by reducing the morbidity and mortality related to TB infections in patients with IBD receiving anti-TNF treatment.
  16. Miura F, Okamoto K, Takada T, Strasberg SM, Asbun HJ, Pitt HA, et al.
    J Hepatobiliary Pancreat Sci, 2018 Jan;25(1):31-40.
    PMID: 28941329 DOI: 10.1002/jhbp.509
    The initial management of patients with suspected acute biliary infection starts with the measurement of vital signs to assess whether or not the situation is urgent. If the case is judged to be urgent, initial medical treatment should be started immediately including respiratory/circulatory management if required, without waiting for a definitive diagnosis. The patient's medical history is then taken; an abdominal examination is performed; blood tests, urinalysis, and diagnostic imaging are carried out; and a diagnosis is made using the diagnostic criteria for cholangitis/cholecystitis. Once the diagnosis has been confirmed, initial medical treatment should be started immediately, severity should be assessed according to the severity grading criteria for acute cholangitis/cholecystitis, and the patient's general status should be evaluated. For mild acute cholangitis, in most cases initial treatment including antibiotics is sufficient, and most patients do not require biliary drainage. However, biliary drainage should be considered if a patient does not respond to initial treatment. For moderate acute cholangitis, early endoscopic or percutaneous transhepatic biliary drainage is indicated. If the underlying etiology requires treatment, this should be provided after the patient's general condition has improved; endoscopic sphincterotomy and subsequent choledocholithotomy may be performed together with biliary drainage. For severe acute cholangitis, appropriate respiratory/circulatory management is required. Biliary drainage should be performed as soon as possible after the patient's general condition has been improved by initial treatment and respiratory/circulatory management. Free full articles and mobile app of TG18 are available at: http://www.jshbps.jp/modules/en/index.php?content_id=47. Related clinical questions and references are also included.
  17. Fulsom BG, Pedlar TK, Adachi I, Aihara H, Al Said S, Asner DM, et al.
    Phys Rev Lett, 2018 Dec 07;121(23):232001.
    PMID: 30576207 DOI: 10.1103/PhysRevLett.121.232001
    We report the observation of ϒ(2S)→γη_{b}(1S) decay based on an analysis of the inclusive photon spectrum of 24.7  fb^{-1} of e^{+}e^{-} collisions at the ϒ(2S) center-of-mass energy collected with the Belle detector at the KEKB asymmetric-energy e^{+}e^{-} collider. We measure a branching fraction of B[ϒ(2S)→γη_{b}(1S)]=(6.1_{-0.7-0.6}^{+0.6+0.9})×10^{-4} and derive an η_{b}(1S) mass of 9394.8_{-3.1-2.7}^{+2.7+4.5}  MeV/c^{2}, where the uncertainties are statistical and systematic, respectively. The significance of our measurement is greater than 7 standard deviations, constituting the first observation of this decay mode.
  18. Seong IS, Vahsen SE, Adachi I, Aihara H, Al Said S, Asner DM, et al.
    Phys Rev Lett, 2019 Jan 11;122(1):011801.
    PMID: 31012694 DOI: 10.1103/PhysRevLett.122.011801
    We report on the first Belle search for a light CP-odd Higgs boson, A^{0}, that decays into low mass dark matter, χ, in final states with a single photon and missing energy. We search for events produced via the dipion transition ϒ(2S)→ϒ(1S)π^{+}π^{-}, followed by the on-shell process ϒ(1S)→γA^{0} with A^{0}→χχ, or by the off-shell process ϒ(1S)→γχχ. Utilizing a data sample of 157.3×10^{6} ϒ(2S) decays, we find no evidence for a signal. We set limits on the branching fractions of such processes in the mass ranges M_{A^{0}}<8.97  GeV/c^{2} and M_{χ}<4.44  GeV/c^{2}. We then use the limits on the off-shell process to set competitive limits on WIMP-nucleon scattering in the WIMP mass range below 5  GeV/c^{2}.
  19. Sibidanov A, Varvell KE, Adachi I, Aihara H, Al Said S, Asner DM, et al.
    Phys Rev Lett, 2018 Jul 20;121(3):031801.
    PMID: 30085771 DOI: 10.1103/PhysRevLett.121.031801
    We report the results of a search for the rare, purely leptonic decay B^{-}→μ^{-}ν[over ¯]_{μ} performed with a 711  fb^{-1} data sample that contains 772×10^{6}  BB[over ¯] pairs, collected near the ϒ(4S) resonance with the Belle detector at the KEKB asymmetric-energy e^{+}e^{-} collider. The signal events are selected based on the presence of a high momentum muon and the topology of the rest of the event showing properties of a generic B-meson decay, as well as the missing energy and momentum being consistent with the hypothesis of a neutrino from the signal decay. We find a 2.4 standard deviation excess above background including systematic uncertainties, which corresponds to a branching fraction of B(B^{-}→μ^{-}ν[over ¯]_{μ})=(6.46±2.22±1.60)×10^{-7} or a frequentist 90% confidence level interval on the B^{-}→μ^{-}ν[over ¯]_{μ} branching fraction of [2.9,10.7]×10^{-7}.
  20. Guido E, Mussa R, Tamponi U, Aihara H, Al Said S, Asner DM, et al.
    Phys Rev Lett, 2018 Aug 10;121(6):062001.
    PMID: 30141661 DOI: 10.1103/PhysRevLett.121.062001
    We report the first observation of the hadronic transition ϒ(4S)→η^{'}ϒ(1S), using 496  fb^{-1} data collected at the ϒ(4S) resonance with the Belle detector at the KEKB asymmetric-energy e^{+}e^{-} collider. We reconstruct the η^{'} meson through its decays to ρ^{0}γ and to π^{+}π^{-}η, with η→γγ. We measure B(ϒ(4S)→η^{'}ϒ(1S))=[3.43±0.88(stat)±0.21(syst)]×10^{-5}, with a significance of 5.7σ.
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