Postmastectomy Radiotherapy Improves Disease-Free Survival of High Risk of Locoregional Recurrence Breast Cancer Patients with T1-2 and 1 to 3 Positive Nodes

Objectives

The indications for post-mastectomy radiotherapy (PMRT) with T1-2 breast cancer and 1-3 positive axillary lymph nodes is still controversial. The purpose of this study was to investigate the role of PMRT in T1-2 breast cancer with 1-3 positive axillary lymph node.

Methods

We retrospectively reviewed the file records of 79 patients receiving PMRT and not receiving PMRT (618 patients).

Results

The median follow-up was 65 months. Multivariate analysis showed that PMRT was an independent prognostic factor of locoregional recurrence-free survival (LRFS) (P = 0.010). Subgroup analysis of patients who did not undergo PMRT showed that pT stage, number of positive axillary lymph nodes, and molecular subtype were independent prognostic factors of LRFS. PMRT improved LRFS in the entire group (P = 0.005), but did not affect distant metastasis-free survival (DMFS) (P = 0.494), disease-free survival (DFS) (P = 0.215), and overall survival (OS) (P = 0.645). For patients without PMRT, the 5-year LRFS of low-risk patients (0–1 risk factor for locoregional recurrence) of 94.5% was significantly higher than that of high-risk patients (2-3 risk factors for locoregional recurrence) (80.9%, P < 0.001). PMRT improved LRFS (P = 0.001) and DFS (P = 0.027) in high-risk patients, but did not improve LRFS, DMFS, DFS, and OS in low-risk patients.

Conclusions

PMRT is beneficial in patients with high risk of locoregional recurrence breast cancer patients with T1-2 and 1 to 3 positive nodes.     

Differential expression of genes involved in alternative glycolytic pathways,phosphorus scavenging and recycling in response to aluminum and phosphorus interactions in <Emphasis Type="Italic">Citrus</Emphasis> roots

The objective was to determine the possible links between the expression levels of genes involved in alternative glycolytic pathways, phosphorus (P) scavenging and recycling and Citrus tolerance to aluminum (Al) and/or P-deficiency. ‘Xuegan’ (Citrus sinensis) and ‘Sour pummelo’ (Citrus grandis) seedlings were irrigated for 18 weeks with nutrient solution containing 0 and 1.2 mM AlCl₃·6H₂O × 0, 50 and 200 μM KH₂PO₄. C. sinensis displayed more tolerant to Al and P-deficiency than C. grandis. Under Al stress, C. sinensis accumulated more Al in roots and less Al in shoots than C. grandis. P concentration was higher in C. sinensis shoots and roots than in C. grandis ones. C. sinensis roots secreted more malate and citrate than C. grandis ones when exposed to Al. Al-induced-secretion of malate and citrate by excised roots from Al-treated seedlings decreased with increasing P supply. Al-induced-secretion of malate and citrate from roots and Al precipitation by P in roots might be responsible for Al-tolerance of C. sinensis. qRT-PCR analysis showed that Al-activated malate transporter (ALMT1), ATP-dependent phosphofructokinase (ATP-PFK), pyrophosphate-dependent phosphofructokinase (PPi-PFK), tonoplast adenosine-triphosphatase subunit A (V-ATPase A), tonoplast pyrophosphatase (V-PPiase), pyruvate kinase (PK), acid phosphatase (APase), phosphoenolpyruvate carboxylase (PEPC), malic enzyme (ME) and malate dehydrogenase (MDH) genes might contribute to the tolerance of Citrus to Al and/or P-deficiency, but any single gene could not explain the differences between the two species. Citrus tolerance to Al and/or P-deficiency might be caused by the coordinated regulation of gene expression involved in alternative glycolytic pathways, P scavenging and recycling.     

CO2 assimilation, ribulose-1,5-bisphosphate carboxylase/oxygenase, carbohydrates and photosynthetic electron transport probed by the JIP-test, of tea leaves in response to phosphorus supply

Background  

Although the effects of P deficiency on tea (Camellia sinensis (L.) O. Kuntze) growth, P uptake and utilization as well as leaf gas exchange and Chl a fluorescence have been investigated, very little is known about the effects of P deficiency on photosynthetic electron transport, photosynthetic enzymes and carbohydrates of tea leaves. In this study, own-rooted 10-month-old tea trees were supplied three times weekly for 17 weeks with 500 mL of nutrient solution at a P concentration of 0, 40, 80, 160, 400 or 1000 μM. This objective of this study was to determine how P deficiency affects CO₂ assimilation, Rubisco, carbohydrates and photosynthetic electron transport in tea leaves to understand the mechanism by which P deficiency leads to a decrease in CO₂ assimilation.     

Effects of glucose-dependent insulinotropic peptide on behavior

Glucose-dependent insulinotropic peptide (GIP) is an incretin hormone that rises rapidly in response to nutrient ingestion. The GIP receptor is widely expressed in the brain including the brain stem, telencephalon, diencephalon, olfactory bulb, pituitary, and cerebellum. Until recently it was not clear what the endogenous ligand for this receptor was because no GIP expression had been demonstrated in the brain. GIP synthesis has now been documented in the dentate gyrus of the hippocampus. To define GIP effects on behavior we utilized a mouse model a GIP-overexpressing transgenic mouse (GIP Tg). Specifically, anxiety-related behavior, exploration, memory, and nociception were examined. Compared to age-matched adult male C57BI/6 controls GIP Tg mice displayed enhanced exploratory behavior in the open-field locomotor activity test. GIP Tg mice also demonstrated increased performance in some of the motor function tests. These data suggest that the GIP receptor plays a role in the regulation of locomotor activity and exploration. To our knowledge, this is the first report of effects of GIP on behavior.     

Effects of manganese-excess on CO<Subscript>2</Subscript> assimilation,ribulose-1,5-bisphosphate carboxylase/oxygenase,carbohydrates and photosynthetic electron transport of leaves,and antioxidant systems of leaves and roots in <Emphasis Type="Italic">Citrus grandis</Emphasis>seedlings

Background  

Very little is known about the effects of manganese (Mn)-excess on citrus photosynthesis and antioxidant systems. Seedlings of sour pummelo (Citrus grandis) were irrigated for 17 weeks with nutrient solution containing 2 μM (control) or 500 μM (excess) MnSO₄. The objective of this study were to understand the mechanisms by which Mn-excess leads to a decrease in CO₂ assimilation and to test the hypothesis that Mn-induced changes in antioxidant systems differ between roots and leaves.     

Molecular basis of β thalassemia in South China

Summary The phenotype of thalassemia can be caused by over 40 different mutations. To set up a prenatal diagnosis program using DNA analysis, it is important to determine the type and frequency of mutation in a particular geographic area. We have delineated the molecular lesions that cause thalassemia in the Guangdong province of China, and found six mutations in four different haplotypes. The surprising finding that five of these mutations each occur in two different haplotypes suggests the occurrence of crossing over or gene conversion events at the -globin locus. The delineation of the haplotypes and mutations will permit the choice of the appropriate probes for prenatal detection of thalassemia in this part of China.     

Root release and metabolism of organic acids in tea plants in response to phosphorus supply

Self-rooted, 10-month-old, uniform tea [Camellia sinensis (L.) O. Kuntze cv. Huangguanyin] plants were supplied for 17 weeks with 0, 40, 80, 160, 400, or 1000μM phosphorus (P) to investigate the effects of P supply on root citrate and malate release, the concentrations of malate and citrate and the activities of acid-metabolizing enzymes in leaves and roots. Root malate release and accumulation was induced by both 0 and 40μM P, while root citrate release and accumulation was induced only by 0μM P. Phosphorus-deficiency-induced malate and citrate release coincided with higher concentrations of root malate and citrate. The higher concentrations of malate and citrate were accompanied by increased activities of phosphoenolpyruvate carboxylase (PEPC), phosphoenolpyruvate phosphatase (PEPP), citrate synthase (CS) and NAD-malic enzyme (NAD-ME) and decreased activities of pyruvate kinase (PK), NADP-ME and NADP-isocitrate dehydrogenase (NADP-IDH) in roots. In contrast to roots, malate accumulated in the leaves only in response to 0μM P, and no change was observed in citrate levels. The P-deficiency-induced leaf malate accumulation coincided with increased activities of NADP-ME, NAD-ME and PK. Overall, the P-deficiency-induced changes in organic acid (OA) metabolism differed between roots and leaves. The high tolerance of tea plants to P-deficiency might be involved in two major processes: (a) increasing the availability of P by inducing root release of OA anions; and (b) improving the ability to use P efficiently by inducing bypass enzymes involved in tissue P economy.     

CO2 assimilation,photosystem II photochemistry,carbohydrate metabolism and antioxidant system of citrus leaves in response to boron stress

Seedlings of Citrus grandis were fertilized every other days for 15 weeks with nutrient solution containing 0 (deficiency), 10 μM (control) or 500 μM (excess) H₃BO₃. CO₂ assimilation and chlorophyll (Chl) content decreased to a greater degree in B-deficient than in B-excess leaves, but photosynthetic enzyme activities were similarly decreased. Starch accumulated in B-deficient leaves, but not in B-excess ones. Chlorophyll a fluorescence transient showed that the positive L- and K-steps were more pronounced in B-excess than in B-deficient leaves. Maximum quantum yield of primary photochemistry (F_v/F_m), maximum variable fluorescence (F_v), oxygen-evolving complex (OEC) were less decreased in B-deficient than in B-excess leaves, whereas minimum fluorescence (F₀) was less increased in B-deficient leaves. Boron-deficient leaves displayed higher or similar antioxidant enzyme activities and higher ascorbate (AsA) and reduced glutathione (GSH) contents compared to B-excess leaves. Content of thiobarbituric acid (TBA) reactive compounds was less increased by B-deficiency than by B-excess. We conclude that B-deficient leaves are less damaged by oxidative stress than B-excess leaves due to their higher ability to scavenge reactive oxygen species. Both the donor (i.e. the OEC) and the acceptor sides of photosystem II were less photoinhibited by B-deficiency than by B-excess. The greater decrease in CO₂ assimilation and Chl content in B-deficient leaves may be caused by the excessive accumulation of starch. The reduction of CO₂ assimilation by B-excess is probably caused by a combination of factors such as oxidative damage, reduced photosynthetic enzyme activities and impaired electron transport capacity.     

Phosphorus alleviates aluminum-induced inhibition of growth and photosynthesis in Citrus grandis seedlings

Limited data are available on the effects of phosphorus (P) and aluminum (Al) interactions on Citrus spp. growth and photosynthesis. Sour pummelo (Citrus grandis) seedlings were irrigated for 18 weeks with nutrient solution containing 50, 100, 250 and 500 μM KH₂PO₄× 0 and 1.2 mM AlCl₃· 6H₂O. Thereafter, P and Al in roots, stems and leaves, and leaf chlorophyll (Chl), CO₂ assimilation, ribulose‐1,5‐bisphosphate carboxylase/oxygenase (Rubisco) and Chl a fluorescence (OJIP) transients were measured. Under Al stress, P increased root Al, but decreased stem and leaf Al. Shoot growth is more sensitive to Al than root growth, CO₂ assimilation and OJIP transients. Al decreased CO₂ assimilation, Rubisco activity and Chl content, whereas it increased or did not affect intercellular CO₂ concentration. Al affected CO₂ assimilation more than Rubisco and Chl under 250 and 500 μM P. Al decreased root, stem and leaf P, leaf maximum quantum yield of primary photochemistry (F_v/F_m) and total performance index (PI_tot,abs), but increased leaf minimum fluorescence (F_o), relative variable fluorescence at K‐ and I‐steps. P could alleviate Al‐induced increase or decrease for all these parameters. We conclude that P alleviated Al‐induced inhibition of growth and impairment of the whole photosynthetic electron transport chain from photosystem II (PSII) donor side up to the reduction of end acceptors of photosystem I (PSI), thus preventing photosynthesis inhibition through increasing Al immobilization in roots and P level in roots and shoots. Al‐induced impairment of the whole photosynthetic electron transport chain may be associated with growth inhibition.