LAURA MASAMI SUMITA

(Fonte: Lattes)
Índice h a partir de 2011
8
Projetos de Pesquisa
Unidades Organizacionais
SCVIRO-83, Instituto de Medicina Tropical
LIM/52 - Laboratório de Virologia, Hospital das Clínicas, Faculdade de Medicina

Resultados de Busca

Agora exibindo 1 - 4 de 4
  • article 7 Citação(ões) na Scopus
    Prospective study of human herpesvirus 8 oral shedding, viremia, and serological status among human immunodeficiency virus seropositive and seronegative individuals in Sao Paulo, Brazil
    (2017) BRAZ-SILVA, Paulo H.; TOZETTO-MENDOZA, Tania R.; SUMITA, Laura M.; FREIRE, Wilton; PALMIERI, Michelle; CANTO, Alan M. do; AVELINO-SILVA, Vivian I.; GALLOTTINI, Marina; MAYAUD, Philippe; PANNUTI, Claudio S.
    Human herpesvirus 8 (HHV-8) is a gamma-herpesvirus and etiological agent of all forms of Kaposi sarcoma (KS). Saliva may play an important role in HHV-8 transmission in specific populations. Little is known about HHV-8 oral shedding pattern and the possible correlation with the HHV-8 serological profile and viremia. A prospective study was conducted of HHV-8 salivary excretion among human immunodeficiency virus HIV-seronegative (n = 47) and -seropositive (n = 44) homosexual men and HIV-seropositive women (n = 32) over a 6-month period with monthly HHV-8 serologies (immunofluorescence assays to identify antibodies to latent and lytic HHV-8 viral proteins, and a whole-virus HHV-8 enzyme-linked immunosorbent assay [ELISA]), monthly HHV-8 DNA serum/plasma detection, and daily self-collected oral rinses for HHV-8-DNA detection using real-time polymerase chain reaction. HHV-8 seropositivity was 51.1%, 63.6%, and 37.5%, in the three studied groups. There was no case of HHV-8 DNA detection in serum/plasma. Intermittent detection of oral HHV-8 DNA was observed during 5.1% (110/2,160) of visits among 28% (18/64) of HHV-8-seropositive individuals, all of whom were males and HHV-8 ELISA seropositive. In immunologically controlled populations of Brazil, HHV-8 oral shedding was limited to HHV-8-seropositive men, occurred infrequently and intermittently, and was not linked to HHV-8 viremia, suggesting a limited potential for oral or blood transmission.
  • article 2 Citação(ões) na Scopus
    Polyomavirus Detection in Multiple Sclerosis Patients Under Natalizumab Therapy: Profile and Frequency of Urinary Shedding
    (2017) NALI, Luiz Henrique; FINK, Maria Cristina; OLIVAL, Guilherme S. do; MORAES, Lenira; CALLEGARO, Dagoberto; TILBERY, Charles Peter; VIDAL, Jose Ernesto; SUMITA, Laura Masami; OLIVEIRA, Augusto C. Penalva de; ROMANO, Camila M.
    Patients undergoing Natalizumab (NTZ) therapy are at risk of progressive multifocal leukoence-phalopathy (PML). Besides John Cunningham virus (JCV), BK polyomavirus might represent an additional concern for such patients since it can also infect CNS cells. Currently, data regarding the presence of anti-JCV antibodies added to previous immunosuppressive therapy and prolonged NTZ therapy has been used to classify patients at risk of developing PML. Here, we investigated the profile shedding of JCV and BKV in multiple sclerosis (MS) patients during treatment with NTZ. Serial blood and urine samples from 97 MS patients receiving either NTZ or beta-interferon were investigated for polyomavirus shedding. While all blood samples tested negative, 36% of the patients shed polyomavirus in the urine in at least one time point. From these, 21.7%, 9.3%, and 5.1% shed JCV, BKV, and both polyomavirus, respectively. No difference was observed between the rates of urinary shedding of patients treated with NTZ (38.9%) and patients treated with other drugs (34.5%), also no PML event was diagnosed during the follow-up. Therefore, urinary shedding might not be interfered by therapy condition. In our study, we also observed 14/ 27 (52%) of anti-JCV antibodies prevalence, and nearly half of them (42%) did not present any event of urinary shedding during the follow-up. (C) 2016 Wiley Periodicals, Inc.
  • article 16 Citação(ões) na Scopus
    Association of Parasite Load Levels in Amniotic Fluid With Clinical Outcome in Congenital Toxoplasmosis
    (2017) YAMAMOTO, Lidia; TARGA, Lilia S.; SUMITA, Laura M.; SHIMOKAWA, Paulo T.; RODRIGUES, Jonatas C.; KANUNFRE, Kelly A.; OKAY, Thelma S.
    OBJECTIVE: To correlate neonatal and infant clinical outcome with parasite load in amniotic fluid (AF). METHODS: We conducted a retrospective cohort study of 122 children whose mothers had toxoplasmosis during pregnancy. The children were monitored from birth to 12 months old. Stored AF samples were obtained at maternal diagnosis and tested by quantitative polymerase chain reaction. Gestational age at maternal infection, quantitative polymerase chain reaction results, neonatal anti-Toxoplasma gondii immunoglobulin (Ig) M, and clinical outcome at 12 months were correlated. RESULTS: Maternal infection occurred in 18 of 122 (14.7%) and 104 of 122 (85.2%) women in the first and second trimesters, respectively. At birth, IgM was present in 107 of 122 (87.7%) neonates and 36 (29.5%) were symptomatic. Of these, half occurred in the first and the other half in the second trimester and 6 of 36 had severe infections (16.7% of symptomatic, 4.9% of total), all infected in the first trimester. Parasite load levels were highly variable (median 35 parasites/mL, range 2-30,473). Logistic regression correlated symptomatic infection with gestational age (odds ratio [OR] 0.47, CI 0.31-0.73) and parasite load (OR 2.04, CI 1.23-3.37), but not with positive IgM (OR 6.81, CI 0.86-53.9). Negative correlations were found between gestational age and parasite load (rs -0.780, CI -0.843 to -0.696), gestational age and symptoms (rs -0.664, CI -0.755 to -0.547), but not gestational age and IgM (rs -0.136, CI -0.311 to 0.048). Parasite load levels distributed by percentile showed that all symptomatic patients appeared from the 75th percentile and all severe infections from the 95th percentile. Load rankings showed doubled the OR for each 20 parasite/mL increment. Parasite load was associated with symptomatic infections (area under the curve 0.959, CI 0.908-0.987) as well as gestational age (area under the curve 0.918, CI 0.855-0.960) and both parameters combined (area under the curve 0.969, CI 0.920-0.992). CONCLUSION: Parasite load in AF is associated with the clinical outcome in congenital toxoplasmosis, irrespective of gestational age at maternal infection.
  • article 8 Citação(ões) na Scopus
    Oral shedding of human herpesviruses in patients undergoing radiotherapy/chemotherapy treatment for head and neck squamous cell carcinoma
    (2017) PALMIERI, Michelle; MARTINS, Victor Adriano de Oliveira; SUMITA, Laura Masami; TOZETTO-MENDOZA, Tania Regina; ROMANO, Bruna Baraldi; MACHADO, Clarisse Martins; PANNUTI, Claudio Sergio; BRANDAO, Thais Bianca; RIBEIRO, Ana Carolina Prado; CORREA, Luciana; BRAZ-SILVA, Paulo Henrique
    Opportunistic infections may affect the oral mucosa of patients undergoing radio/chemotherapy through exacerbation of oral mucositis. The aim of this study is to evaluate the oral shedding of all eight human herpesviruses and its possible association with oral mucositis. In this prospective cohort study, we analyzed oral rinse samples, collected weekly, from 20 patients during radiotherapy treatment. Serologic status to HSV1 and HSV2, EBV, CMV, and VZV in three different periods was performed by ELISA assay. PCR and enzymatic digestion was performed to detect HSV1, HSV2, EBV, CMV, VZV, HHV6, HHV7, and HHV8. Oral mucositis was evaluated according to the WHO criteria. Oral shedding of EBV, HHV6, and HHV7 was observed in all weeks of radiotherapy. Considering the episodes of shedding, the highest frequency was found in patients with EBV excretion (55.0%). No virus reactivation was observed by serological analysis. EBV oral shedding frequency was significantly higher than that of other viruses and showing a positive correlation with oral mucositis grade >= 2. There was a positive correlation between EBV oral shedding and oral mucositis grade >= 2, particularly after 3 weeks of radiotherapy, a period in which the severity of mucositis was statistically higher. These findings allow us to infer that the local inflammatory environment in mucositis grade >= 2 is more favorable for EBV replication. Mucositis is a frequent and important side effect of radio/chemotherapy treatment. Understanding the possible participation of viruses in the mechanism of this condition is important to develop strategies for treatment and prevention.