Plant Age and Soil Texture Rather Than the Presence of Root Hairs Cause Differences in Maize Resource Allocation and Root Gene Expression in the Field.

Understanding the biological roles of root hairs is key to projecting their contributions to plant growth and to assess their relevance for plant breeding. The objective of this study was to assess the importance of root hairs for maize nutrition, carbon allocation and root gene expression in a field experiment. Applying wild type and root hairless rth3 maize grown on loam and sand, we examined the period of growth including 4-leaf, 9-leaf and tassel emergence stages, accompanied with a low precipitation rate. rth3 maize had lower shoot growth and lower total amounts of mineral nutrients than wild type, but the concentrations of mineral elements, root gene expression, or carbon allocation were largely unchanged. For these parameters, growth stage accounted for the main differences, followed by substrate. Substrate-related changes were pronounced during tassel emergence, where the concentrations of several elements in leaves as well as cell wall formation-related root gene expression and C allocation decreased. In conclusion, the presence of root hairs stimulated maize shoot growth and total nutrient uptake, but other parameters were more impacted by growth stage and soil texture. Further research should relate root hair functioning to the observed losses in maize productivity and growth efficiency.

Low incidence of prostate cancer identified in the transition and anterior zones with transperineal biopsy.

PURPOSE: Determine the incidence of anterior (AZ) and transition (TZ) zone prostate cancers using a transperineal mapping approach. METHODS: A retrospective review of 137 patients with history of previous negative biopsy undergoing transperineal saturation biopsy for an elevated prostate-specific antigen (PSA), high-grade prostate intraepithelial neoplasia, atypical small acinar proliferation history, or abnormal digital rectal exam. The number of biopsy cores was determined by prostate volume and obtained using a predefined template. The electronic medical records were reviewed for patients' clinical and pathological characteristics. RESULTS: Forty-one of 137 patients (31.4%) had positive biopsy for prostate adenocarcinoma; 11 were from 24-core, 19 from 36-core, and 11 from 48-core sampling. Glands > 45 mL had a mean of 1.7 previous biopsies and a PSA of 9.1 ng/mL. Glands < 30 mL were 1.3 and 6.3 ng/mL and glands 30-45 mL were 1.4 and 6.5 ng/mL. Glands < 45 mL had a higher number of positive biopsies per total cores. Seven patients chose active surveillance while 34 chose treatment. Of the 36- and 48-cores biopsies, 2.2% and 1.5%, respectively, were positive in the TZ. One patient was AZ-positive, 1 was TZ-positive, and 18 were peripheral zone (PZ)-positive alone. Twelve patients had cancer detected in PZ and TZ. Two patients developed urinary retention and one had a urine infection. CONCLUSION: Transperineal saturation biopsy is a safe and efficacious method of prostate cancer detection in patients with previous negative biopsy and high suspicion for cancer. Few cancers were found to originate in the TZ or AZ alone. We recommend that initial biopsy templates should sample PZ with less focus on the TZ.

Value of ultrasound and magnetic resonance imaging in the preoperative evaluation of suspected ovarian masses.

BACKGROUND: The stage of ovarian carcinoma at diagnosis directly affects prognosis. Thus, thorough pretreatment evaluation is basic to the successful management of suspected ovarian masses. Among currently available imaging techniques in characterization of suspected ovarian neoplasms, sonography (US) is indisputedly the primary imaging approach. When US is inconclusive, magnetic resonance imaging (MRI) is generally prefered to computed tomography (CT). MATERIALS AND METHODS: 93 patients, who on the basis of clinical findings were suspected to have ovarian cancer and who were scheduled for subsequent surgical staging underwent preoperative transvaginal and abdominal ultrasound as well as magnetic resonance imaging in a prospective comparative study. US and MR images were evaluated for their information on the characterization and staging of the ovarian masses. RESULTS: MRI correctly characterized malignant and benign tumors in 89% of cases versus 85% by ultrasound. The site of the primary tumor was correctly diagnosed in 94% of cases by MRI vs. 90% by ultrasound. For US, the positive predictive value was 85%, the negative predictive value 73% vs. 92% and 89% for MRI. In differentiation of nonadvanced disease from advanced malignancy, US showed a false-positive rate of 0.416 and false-negative rate of 0.258 vs. 0.125 and 0.032 respectively, for MRI. CONCLUSION: MRI was superior in diagnosis of malignant ovarian masses though US, too, performed well at lesion detection and characterization. With regard to tumor staging MRI is emerging as a problem-solving modality and may allow more appropriate clinical decisions to be made in selected patients with complex adnexal disease.