39 research outputs found
Optimizing resource distribution and crop productivity in hedgerow intercropping by manipulating tree arrangement
The potential of tree arrangement in
optimizing radiation and soil water distribution and
crop yield of hedgerow intercropping systems was
investigated using a Jatropha curcas–Pennisetum
clandestinum (kikuyu) system (Ukulinga, South
Africa). Treatments (1110 t ha-1) of Jatropha-only
(JO), single-row Jatropha and kikuyu (SR), and
double-row Jatropha and kikuyu (DR) were used.
Treatments had asymmetrical radiation distribution
across tree–crop (T–C) interfaces and different radiation
interception by trees (JO: 27 %, SR: 11 %, DR:
8 %). Soil water varied among treatments and was
asymmetrically distributed showing no consistent
trend towards trees. Evapotranspiration was higher
(p\0.05) in SR than DR (13–65 %) and JO
(16–37 %) for most part of the season. Estimated fine
tree roots distribution was symmetrical in DR but not
JO and SR. Total roots in SR were concentrated in the
top 0.2 m (91 %) and beneath tree row (30 %), and
varied inconsistently with distance from trees. Grass
yields increased farther from tree rows and were
higher in SR (8.7 t ha-1 in 2006–2007; 4.3 t ha-1 in 2007–2008) than DR (by \9 %). Radiation use
efficiency of kikuyu (0.14–0.44 g MJ-1) also
increased with distance from trees but irradiance
correlated with grass yields poorly (R2\0.32) despite
high rainfall and no nutrient limitation. Considering
total productivity and evapotranspiration, DR was
better tree arrangement than SR. Water availability
dictated T–C interactions and intercrop yield more
than radiation. It was possible to optimize radiation
and water distribution and intercrop growth by
manipulating tree arrangement without changing
density.Water Research Commission (WRC) of South Africa project (K5/1480/1/12).http://link.springer.com/journal/104572017-10-30hb2016Plant Production and Soil Scienc
High placenta-specific 1/low prostate-specific antigen expression pattern in high-grade prostate adenocarcinoma
BACKGROUND: The scarcity of effective therapeutic approaches for prostate cancer (PCa) has encouraged steadily growing interest for the identification of novel antigenic targets. Placenta-specific 1 (PLAC1) is a novel cancer-testis antigen with reported ectopic expression in a variety of tumors and cancer cell lines. The purpose of the present study was to investigate for the first time the differential expression of PLAC1 in PCa tissues. METHODS: We investigated the differential expression of PLAC1 in PCa, high-grade prostatic intraepithelial neoplasia (HPIN), benign prostatic hyperplasia (BPH), and nonneoplastic/nonhyperplastic prostate tissues using microarray-based immunohistochemistry (n = 227). The correlation of PLAC1 expression with certain clinicopathological parameters and expression of prostate-specific antigen (PSA), as a prostate epithelial cell differentiation marker, were investigated. RESULTS: Placenta-specific 1 (PLAC1) expression was increased in a stepwise manner from BPH to PCa, which expressed highest levels of this molecule, while in a majority of normal tissues, PLAC1 expression was not detected. Moreover, PLAC1 expression was positively associated with Gleason score (p ≤ 0.001). Interestingly, there was a negative correlation between PLAC1 and PSA expression in patients with PCa and HPIN (p ≤ 0.01). Increment of PLAC1 expression increased the odds of PCa and HPIN diagnosis (OR 49.45, 95 % CI for OR 16.17-151.25). CONCLUSION: Our findings on differential expression of PLAC1 in PCa plus its positive association with Gleason score and negative correlation with PSA expression highlight the potential usefulness of PLAC1 for targeted PC therapy especially for patients with advanced disease
