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Fulltext Influence of different pre-processing methods in predicting sugarcane quality from near-infrared (NIR) spectral data

Lazim, S. S. R. M., Nawi, N. M., Rasli, A. M. M., Chen, G., Jensen, T.

International Food Research Journal, 2016;23(101):231-236.
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The influence of different data pre-processing methods (smoothing by moving average (MA),
multiplicative scatter correction (MSC), Savitzky-Golay (SG), standard normal variate (SNV)
and mean normalization (MN) on the prediction of sugar content from sugarcane samples was
investigated. The performance of these pre-processing methods was evaluated using spectral
data collected from 292 sugarcane internode samples using a visible-shortwave near infrared
spectroradiometer (VNIRS). Partial least square (PLS) method was applied to develop both
calibration and prediction models for the samples. If no pre-processing method was applied,
the coefficient of determination (R2) values for both reflectance and absorbance data were 0.81
and 0.86 respectively. The highest prediction accuracy values were obtained when the data was
treated with MSC method, where the R2 values for reflectance and absorbance being 0.85 and
0.87, respectively. From this study, it was concluded that pre-processing can improve the model
performances where MSC method was found to give the highest prediction accuracy value.
Fulltext Serum testosterone and prostate cancer in men with germline BRCA1/2 pathogenic variants

Dias A, Brook MN, Bancroft EK, Page EC, Chamberlain A, Saya S, et al.

BJUI Compass, 2023 May;4(3):361-373.
PMID: 37025481 DOI: 10.1002/bco2.156

OBJECTIVES: The relation of serum androgens and the development of prostate cancer (PCa) is subject of debate. Lower total testosterone (TT) levels have been associated with increased PCa detection and worse pathological features after treatment. However, data from the Reduction by Dutasteride of Prostate Cancer Events (REDUCE) and Prostate Cancer Prevention (PCPT) trial groups indicate no association. The aim of this study is to investigate the association of serum androgen levels and PCa detection in a prospective screening study of men at higher genetic risk of aggressive PCa due to BRCA1/2 pathogenic variants (PVs), the IMPACT study.
METHODS: Men enrolled in the IMPACT study provided serum samples during regular visits. Hormonal levels were calculated using immunoassays. Free testosterone (FT) was calculated from TT and sex hormone binding globulin (SHBG) using the Sodergard mass equation. Age, body mass index (BMI), prostate-specific antigen (PSA) and hormonal concentrations were compared between genetic cohorts. We also explored associations between age and TT, SHBG, FT and PCa, in the whole subset and stratified by BRCA1/2 PVs status.
RESULTS: A total of 777 participants in the IMPACT study had TT and SHBG measurements in serum samples at annual visits, giving 3940 prospective androgen levels, from 266 BRCA1 PVs carriers, 313 BRCA2 PVs carriers and 198 non-carriers. The median number of visits per patient was 5. There was no difference in TT, SHBG and FT between carriers and non-carriers. In a univariate analysis, androgen levels were not associated with PCa. In the analysis stratified by carrier status, no significant association was found between hormonal levels and PCa in non-carriers, BRCA1 or BRCA2 PVs carriers.
CONCLUSIONS: Male BRCA1/2 PVs carriers have a similar androgen profile to non-carriers. Hormonal levels were not associated with PCa in men with and without BRCA1/2 PVs. Mechanisms related to the particularly aggressive phenotype of PCa in BRCA2 PVs carriers may therefore not be linked with circulating hormonal levels.
Fulltext Physical fitness in community-dwelling older adults is linked to dietary intake, gut microbiota, and metabolomic signatures

Castro-Mejía JL, Khakimov B, Krych Ł, Bülow J, Bechshøft RL, Højfeldt G, et al.

Aging Cell, 2020 03;19(3):e13105.
PMID: 31967716 DOI: 10.1111/acel.13105

When humans age, changes in body composition arise along with lifestyle-associated disorders influencing fitness and physical decline. Here we provide a comprehensive view of dietary intake, physical activity, gut microbiota (GM), and host metabolome in relation to physical fitness of 207 community-dwelling subjects aged +65 years. Stratification on anthropometric/body composition/physical performance measurements (ABPm) variables identified two phenotypes (high/low-fitness) clearly linked to dietary intake, physical activity, GM, and host metabolome patterns. Strikingly, despite a higher energy intake high-fitness subjects were characterized by leaner bodies and lower fasting proinsulin-C-peptide/blood glucose levels in a mechanism likely driven by higher dietary fiber intake, physical activity and increased abundance of Bifidobacteriales and Clostridiales species in GM and associated metabolites (i.e., enterolactone). These factors explained 50.1% of the individual variation in physical fitness. We propose that targeting dietary strategies for modulation of GM and host metabolome interactions may allow establishing therapeutic approaches to delay and possibly revert comorbidities of aging.
Fulltext Prostate-specific antigen velocity in a prospective prostate cancer screening study of men with genetic predisposition

Mikropoulos C, Selkirk CGH, Saya S, Bancroft E, Vertosick E, Dadaev T, et al.

Br J Cancer, 2018 Jan;118(2):266-276.
PMID: 29301143 DOI: 10.1038/bjc.2017.429

BACKGROUND: Prostate-specific antigen (PSA) and PSA-velocity (PSAV) have been used to identify men at risk of prostate cancer (PrCa). The IMPACT study is evaluating PSA screening in men with a known genetic predisposition to PrCa due to BRCA1/2 mutations. This analysis evaluates the utility of PSA and PSAV for identifying PrCa and high-grade disease in this cohort.
METHODS: PSAV was calculated using logistic regression to determine if PSA or PSAV predicted the result of prostate biopsy (PB) in men with elevated PSA values. Cox regression was used to determine whether PSA or PSAV predicted PSA elevation in men with low PSAs. Interaction terms were included in the models to determine whether BRCA status influenced the predictiveness of PSA or PSAV.
RESULTS: 1634 participants had ⩾3 PSA readings of whom 174 underwent PB and 45 PrCas diagnosed. In men with PSA >3.0 ng ml-l, PSAV was not significantly associated with presence of cancer or high-grade disease. PSAV did not add to PSA for predicting time to an elevated PSA. When comparing BRCA1/2 carriers to non-carriers, we found a significant interaction between BRCA status and last PSA before biopsy (P=0.031) and BRCA2 status and PSAV (P=0.024). However, PSAV was not predictive of biopsy outcome in BRCA2 carriers.
CONCLUSIONS: PSA is more strongly predictive of PrCa in BRCA carriers than non-carriers. We did not find evidence that PSAV aids decision-making for BRCA carriers over absolute PSA value alone.