Search

Objectives: This study examined Mycobacterium tuberculosis (MTB)-secreted MPT64 as a surrogate of bacterial viability for the diagnosis of active pulmonary TB (PTB) and for follow-up treatment., Methods: In this proof-of-concept prospective study, 50 PTB patients in the Tokyo metropolitan region, between 2017 and 2018, were consecutively included and 30 healthy individuals were also included. Each PTB patient submitted sputum on days 0, 14 and 28 for diagnosis and follow-up, and each healthy individual submitted one sputum sample. The following were performed: smear microscopy, Xpert MTB/RIF, MGIT and solid culture, and MPT64 detection on the sputum samples. Ultrasensitive ELISA (usELISA) was used to detect MPT64. The receiver operating characteristic analyses for diagnosis and follow-up revealed the optimal cut-off value of MPT64 absorbance for detecting culture positivity at multiple intervals., Results: The sensitivity of MPT64 for diagnosing PTB was 88.0% (95% CI 75.7-95.5) and the specificity was 96.7% (95% CI 82.8-99.9). The specificity of MPT64 for predicting negative culture results on day 14 was 89.5% (95% CI 66.9-98.7). The sensitivity of MPT64 for predicting positive culture results on day 28 was 81.0% (95% CI 58.1-94.6)., Conclusions: This study revealed that MPT64 is useful for diagnosing active PTB in patients and predicting treatment efficacy at follow-up., (Copyright © 2020 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

A PCR method for the effective detection of Coxiella burnetii in commercially available mayonnaise was developed. Sample preparations were isolated from 50 g portions of each mayonnaise product by four successive extraction steps in phosphate buffer with 2.0 M NaCl. These extracts were then centrifuged at 20,000 x g for 60 min. DNA was isolated from the solution containing the precipitate with a commercial kit, and amplified quantitatively using real-time PCR that targeted the com1 region of C. burnetii. The recoveries of C. burnetii from 2 kinds of commercial mayonnaise specimens, with a baseline control of 1 x 10(7) particles of the Nine Mile phase II strain, were 85.0 +/- 6.0% and 72.0 +/- 0.4%, respectively. The determination limit of this method was 500 C. burnetii particles per 50 g of mayonnaise. The DNA specimens isolated from 50 different commercial mayonnaise samples sold in Tokyo using this method were amplified using both nested PCR and real-time PCR. No contamination by C. burnetii was detected in any of the mayonnaise samples.

A total of 244 milk samples collected from supermarkets in Tokyo were examined for contamination with Coxiella burnetii. C. burnetii DNA was detected in 131 (53.7%) of the samples by nested PCR. PCR-positive samples were injected into immunosuppressed A/J strain mice. Of the 22 PCR-positive milk samples tested, none resulted in isolation of C. burnetii from the mice. Heat-treatment was sufficient to inactivate C. burnetii in commercial milk. In addition, a PCR detection method for C. burnetii in chicken egg was developed. Egg yolk was added to an equal volume of 1 mol/L of NaCl phosphate buffer and homogenized for removal of protein and lipid. After centrifugal separation, the supernatant was removed, and template DNA in the precipitate was extracted using SDS, proteinase K and NaI. Using such prepared samples, 3.2 x 10(1) C. burnetii particles in 1 g of egg yolk could be detected by nested PCR. All of 200 chicken egg samples collected from supermarkets in Tokyo were negative for C. burnetii by the nested PCR method.

To clarify the development of diabetic nephropathy in Japanese insulin-dependent diabetes mellitus (IDDM), 373 patients with IDDM who had no proteinuria at the first visit to our Diabetes Center were evaluated. The incidence of persistent proteinuria increased rapidly between 10 and 19 years of diabetes duration, and only a few new cases occurred thereafter. Patients whose ages at onset of IDDM were 9-17 years (n = 167) and 18-29 years (n = 90) had rapid development of persistent proteinuria compared to the 0 to 8-year group (n = 116) (p < 0.02 and p < 0.003, respectively). Females (n = 233) developed persistent proteinuria to a greater extent until 24 years of diabetes duration than males (n = 140) (p = 0.17). Development of proteinuria did not vary according to calendar year of diagnosis of IDDM or diabetes duration at the first visit. Renal insufficiency (serum creatinine of 2.0 mg/dL or greater) followed the onset of proteinuria; 60% of the patients with the onset of IDDM between 1951 and 1969 developed renal insufficiency 10 years after the onset of proteinuria, whereas 30% of patients with the onset of IDDM after 1970 developed this condition. Development of renal insufficiency did not vary according to sex, age at onset of IDDM, or age at onset of proteinuria. Renal failure requiring dialysis therapy occurred within 4 years after renal insufficiency. In conclusion, development of diabetic nephropathy in Japanese IDDM exhibits three stages. The onset of proteinuria appears to be influenced by age at onset of IDDM and sex.(ABSTRACT TRUNCATED AT 250 WORDS)

The serum antibodies to human immunodeficiency virus types 1 (HIV-1) and 2 (HIV-2) were examined for among individuals who visited health centers in Tokyo. Of 8,198 sera screened, one was true-positive and 37 false-positive for HIV-1 antibodies. These 37 false-positives and 305 sera from the population groups at risk for HIV-2 (42 sojourners in Africa, 251 homo- and bisexuals, and 19 prostitutes) were further examined for HIV-2 antibodies by indirect immunofluorescence and Western blotting. No antibodies reactive with HIV-2 were detected in the sera examined. Serological cross-reactivity between HIV-1 and HIV-2 was examined by use of rabbit antisera.