Genetic analysis of rice mutants responsible for narrow leaf phenotype and reduced vein number

Leaves are a major site for photosynthesis and a key determinant of plant architecture. Rice produces thin and slender leaves, which consist of the leaf blade and leaf sheath separated by the lamina joint. Two types of vasculature, the large and small vascular bundles, run in parallel, together with a strong structure, the midrib. In this paper, we examined the function of four genes that regulate the width of the leaf blade and the vein number: NARROW LEAF1 (NAL1), NAL2, NAL3 and NAL7. We backcrossed original mutants of these genes with the standard wild-type rice, Taichung 65. We then compared the effect of each mutation on similar genetic backgrounds and examined genetic interactions of these genes. The nal1 single mutation and the nal2 nal3 double mutation showed a severe effect on leaf width, resulting in very narrow leaves. Although vein number was also reduced in the nal1 and nal2 nal3 mutants, the small vein number was more strongly reduced than the large vein number. In contrast, the nal7 mutation showed a milder effect on leaf width and vein number, and both the large and small veins were similarly affected. Thus, the genes responsible for narrow leaf phenotype seem to play distinct roles. The nal7 mutation showed additive effects on both leaf width and vein number, when combined with the nal1 single or the nal2 nal3 double mutation. In addition, observations of inner tissues revealed that cell differentiation was partially compromised in the nal2 nal3 nal7 mutant, consistent with the severe reduction in leaf width in this triple mutant.

Synovial mesenchymal stem cells from osteo- or rheumatoid arthritis joints exhibit good potential for cartilage repair using a scaffold-free tissue engineering approach

OBJECTIVE

To assess whether synovial mesenchymal stem cells (SMSCs) from patients with osteoarthritis (OA) or rheumatoid arthritis (RA) can be used as an alternative cell source for cartilage repair using allogenic tissue engineered construct (TEC).

METHODS

Twenty-five patients (17 female, average age 61.8 years) were divided according to their pathology (control trauma group; N = 6, OA group; N = 6) and RA patients were subdivided into two groups to evaluate the impact of biologics in accordance with whether treated with biologics [Bio(+)RA; N = 7] or not [Bio(-)RA; N = 6]. We compared the following characteristics among these groups: (1) The cell proliferation capacity of SMSCs; (2) The influence of passage number on features of SMSCs; (3) The weight and volume of TEC from the same number of SMSCs; (4) Inflammatory cytokine gene expressions levels of TEC; (5) The chondrogenic potential of TEC; and (6) Osteochondral repair using TEC in athymic nude rats.

RESULTS

SMSCs from the four groups exhibited equivalent features in the above evaluation items. In in vivo studies, the TEC-treated repair tissues for all groups exhibited significantly better outcomes than those for the untreated group and no significant differences among the four TEC groups.

CONCLUSION

SMSCs from OA or RA patients are no less appropriate for repairing cartilage than those from trauma patients and thus, may be an effective source for allogenic cell-based cartilage repair.

Anatomy of the inferior extensor retinaculum and its role in lateral ankle ligament reconstruction: a pictorial essay

The inferior extensor retinaculum (IER) is an aponeurotic structure, which is in continuation with the anterior part of the sural fascia. The IER has often been used to augment the reconstruction of the lateral ankle ligaments, for instance in the Broström-Gould procedure, with good outcomes reported. However, its anatomy has not been described in detail and only a few studies are available on this structure. The presence of a non-constant oblique supero-lateral band appears to be important. This structure defines whether the augmentation of the lateral ankle ligaments reconstruction is performed using true IER or only the anterior part of the sural fascia. It is concluded that the use of this structure will have an impact on the resulting ankle stability.

Survival in stage I-III breast cancer patients by surgical treatment in a publicly funded health care system

BACKGROUND

Recent investigations of breast cancer survival in the United States suggest that patients who receive mastectomy have poorer survival than those who receive breast-conserving surgery (BCS) plus radiotherapy, despite clinically established equivalence. This study investigates breast cancer survival in the publicly funded health care system present in Alberta, Canada.

PATIENTS AND METHODS

Surgically treated stage I-III breast cancer cases diagnosed in Alberta from 2002 to 2010 were included. Demographic, treatment and mortality information were collected from the Alberta Cancer Registry. Unadjusted overall and breast cancer-specific mortality was assessed using Kaplan-Meier and cumulative incidence curves, respectively. Cox proportional hazards models were used to calculate stage-specific mortality hazard estimates associated with surgical treatment received.

RESULTS

A total of 14 939 cases of breast cancer (14 633 patients) were included in this study. The unadjusted 5-year all-cause survival probabilities for patients treated with BCS plus radiotherapy, mastectomy, and BCS alone were 94% (95% CI 93% to 95%), 83% (95% CI 82% to 84%) and 74% (95% CI 70% to 78%), respectively. Stage II and III patients who received mastectomy had a higher all-cause (stage II HR = 1.36, 95% CI 1.13-1.48; stage III HR = 1.74, 95% CI 1.24-2.45) and breast cancer-specific (stage II HR = 1.39, 95% CI 1.09-1.76; stage III HR = 1.79, 95% CI 1.21-2.65) mortality hazard compared with those who received BCS plus radiotherapy, adjusting for patient and clinical characteristics. BCS alone was consistently associated with poor survival.

CONCLUSIONS

Stage II and III breast cancer patients diagnosed in Alberta, Canada, who received mastectomy had a significantly higher all-cause and breast cancer-specific mortality hazard compared with those who received BCS plus radiotherapy. We suggest greater efforts toward educating and encouraging patients to receive BCS plus radiotherapy rather than mastectomy when it is medically feasible and appropriate.

Overexpression analysis suggests that FON2-LIKE CLE PROTEIN1 is involved in rice leaf development

Peptide signaling plays important roles in various developmental processes of plants. Genes encoding CLE proteins, which are processed into CLE signaling peptides, are required for maintenance of the shoot apical meristem and for vascular differentiation. FON2-LIKE CLE PROTEIN1 (FCP1), a member of the CLE gene family, negatively regulates meristem maintenance in both shoot and root apical meristems of rice (Oryza sativa). Here, we examined the role of FCP1 in leaf development. We found that overexpression of FCP1 affects various aspects of leaf development in shoots regenerated from calli, making it difficult to distinguish between the leaf blade and leaf sheath. Differentiation of tissues such as vascular bundle and sclerenchyma was strongly inhibited by FCP1 overexpression. Spatial expression patterns of developmental genes DROOPING LEAF (DL) and OsPINHEAD1 (OsPNH1) were severely affected in the FCP1-overexpressing shoots. Whereas DL was expressed in the central region of leaf primordia in control shoots, DL expression was expanded throughout the leaf primordia of the FCP1-overexpressing shoots in early developmental stages. By contrast, OsPNH1, which is expressed in provascular and developing vascular tissues in normal seedlings, was strongly repressed by FCP1 overexpression. Taken together, our results suggest that FCP1 is involved in the regulation of cell fate determination during leaf development.

VASCULAR PLANT ONE-ZINC FINGER1 and VOZ2 repress the FLOWERING LOCUS C clade members to control flowering time in Arabidopsis

Floral transition is regulated by environmental and endogenous signals. Previously, we identified VASCULAR PLANT ONE-ZINC FINGER1 (VOZ1) and VOZ2 as phytochrome B-interacting factors. VOZ1 and VOZ2 redundantly promote flowering and have pivotal roles in the downregulation of FLOWERING LOCUS C (FLC), a central repressor of flowering in Arabidopsis. Here, we showed that the late-flowering phenotypes of the voz1 voz2 mutant were suppressed by vernalization in the Columbia and FRIGIDA (FRI)-containing accessions, which indicates that the late-flowering phenotype of voz1 voz2 mutants was caused by upregulation of FLC. We also showed that the other FLC clade members, MADS AFFECTING FLOWERING (MAF) genes, were also a downstream target of VOZ1 and VOZ2 as their expression levels were also increased in the voz1 voz2 mutant. Our results suggest that the FLC clade genes integrate signals from VOZ1/VOZ2 and vernalization to regulate flowering.

Abstract P4-08-01: Effects of exercise during adjuvant chemotherapy on clinical outcomes in early stage breast cancer

Background: Observational studies suggest that physical activity following a diagnosis of breast cancer may be associated with a lower risk of recurrence and death. Some studies also suggest possible effect modification by disease stage, body mass index, and receptor status. To date, however, there are no randomized trials examining the effects of exercise on disease outcomes in any cancer patient group. Here, we report an exploratory follow-up of disease outcomes from the Supervised Trial of Aerobic versus Resistance Training (START). Patients and Methods: The START Trial was a Canadian multicenter trial that randomized 242 breast cancer patients starting adjuvant chemotherapy to either usual care (n = 82) or supervised aerobic (n = 78) or resistance (n = 82) exercise for the duration of their chemotherapy. The primary efficacy endpoint for this exploratory analysis was disease-free survival (DFS). Secondary endpoints were overall survival (OS), distant disease-free survival (DDFS), and recurrence-free interval (RFI). The two exercise arms were combined for the analysis (n = 160) and selected subgroups were explored. Results: After a median follow-up of 89 months (IQR 81 to 96), there were 25/160 (15.6%) DFS events in the exercise groups and 18/82 (22.0%) in the control group (log-rank p = 0.21). Eight-year DFS was 82.7% for the exercise groups compared with 75.6% for the control group (Hazard ratio [HR] = 0.68, 95% CI = 0.37-1.24). There were 13/160 (8.1%) deaths in the exercise groups and 11/82 (13.4%) in the control group (log-rank p = 0.21). Eight-year OS was 91.2% in the exercise groups compared with 82.7% in the control group (HR = 0.60, 95% CI = 0.27 to 1.33. There were 20/160 (12.5%) DDFS events in the exercise groups and 16/82 (19.5%) in the control group (log-rank p = 0.15). Eight-year DDFS was 86.7% in the exercise groups compared with 78.3% in the control group (HR = 0.62, 95% CI = 0.32 to 1.19). Finally, there were 20/160 (12.5%) RFI events in the exercise groups and 17/82 (20.7%) in the control group (Gray's p = 0.095). Eight-year cumulative incidence of RFI was 12.6% in the exercise groups compared with 21.6% in the control group (HR = 0.58, 95% CI = 0.30 to 1.11). Subgroup analyses for DFS and RFI suggested stronger effects for women who were overweight/obese, had stage II/III cancer, receptor positive tumors, HER2 positive tumors, received taxane-based chemotherapies, and received at least 85% of their intended chemotherapy dose-intensity. The most notable subgroup effect was for patients who received optimal chemotherapy dosing with a borderline significant effect for DFS (HR = 0.50, 95% CI = 0.25 to 1.01) and a significant effect for RFI (HR = 0.38, 95% CI = 0.18 to 0.81). Conclusions: In this exploratory follow-up of the START Trial, there was a suggestion that exercise during adjuvant chemotherapy may improve several efficacy endpoints although none achieved statistical significance. Nevertheless, the magnitude of the effects appear to be meaningful with absolute 8-year survival differences between 7% and 9% and relative rate reductions between 30% and 40%. The START Trial provides the first randomized data to suggest that adding exercise to standard chemotherapy for breast cancer may improve outcomes. A definitive phase III trial is warranted.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P4-08-01.

Noninvasive estimation of fibrosis progression overtime using the FIB-4 index in chronic hepatitis C

The FIB-4 index is a simple formula to predict liver fibrosis based on the standard biochemical values (AST, ALT and platelet count) and age. We here investigated the utility of the index for noninvasive prediction of progression in liver fibrosis. The time-course alteration in the liver fibrosis stage between paired liver biopsies and the FIB-4 index was examined in 314 patients with chronic hepatitis C. The average interval between liver biopsies was 4.9 years. The cases that showed a time-course improvement in the fibrosis stage exhibited a decrease in the FIB-4 index, and those that showed deterioration in the fibrosis stage exhibited an increase in the FIB-4 index with a significant correlation (P < 0.001). Increase in the ΔFIB-4 index per year was an independent predictive factor for the progression in liver fibrosis with an odds ratio of 3.90 (P = 0.03). The area under the receiver operating characteristic curve of the ΔFIB-4 index/year for the prediction of advancement to cirrhosis was 0.910. Using a cut-off value of the ΔFIB-4 index/year <0.4 or ≥ 0.4, the cumulative incidence of fibrosis progression to cirrhosis at 5 and 10 years was 34% and 59%, respectively in patients with the ΔFIB-4 index/year ≥0.4, whereas it was 0% and 3% in those with the ΔFIB-4 index/year <0.4 (P < 0.001). In conclusion, measurement of the time-course changes in the FIB-4 index is useful for the noninvasive and real-time estimation of the progression in liver fibrosis.

The `genetic benefits' of female multiple mating reconsidered

In many animals, males can generally increase their fitness by mating with many mates, but females cannot produce more offspring than the number of their eggs. In spite of this restriction, females often mate with more than one male. In species without any male-provided resource benefits, females are thought to obtain some `genetic benefits' from males that enhance offspring quality. The evolution of female multiple mating is often confused with the issue of female mate choice, but mate choice is actually possible in the single-mating situation. Therefore, we still need to explain the possible advantage of multiple mating over single mating.

The phytochrome-interacting vascular plant one-zinc finger1 and VOZ2 redundantly regulate flowering in Arabidopsis

The timing of the transition to flowering in plants is regulated by various environmental factors, including daylength and light quality. Although the red/far-red photoreceptor phytochrome B (phyB) represses flowering by indirectly regulating the expression of a key flowering regulator, FLOWERING LOCUS T (FT), the mechanism of phyB signaling for flowering is largely unknown. Here, we identified two Arabidopsis thaliana genes, VASCULAR PLANT ONE-ZINC FINGER1 (VOZ1) and VOZ2, which are highly conserved throughout land plant evolution, as phyB-interacting factors. voz1 voz2 double mutants, but neither single mutant, showed a late-flowering phenotype under long-day conditions, which indicated that VOZ1 and VOZ2 redundantly promote flowering. voz1 voz2 mutations suppressed the early-flowering phenotype of the phyB mutant, and FT expression was repressed in the voz1 voz2 mutant. Green fluorescent protein-VOZ2 signal was observed in the cytoplasm, and interaction of VOZ proteins with phyB was indicated to occur in the cytoplasm under far-red light. However, VOZ2 protein modified to localize constitutively in the nucleus promoted flowering. In addition, the stability of VOZ2 proteins in the nucleus was modulated by light quality in a phytochrome-dependent manner. We propose that partial translocation of VOZ proteins from the cytoplasm to the nucleus mediates the initial step of the phyB signal transduction pathway that regulates flowering.

Rates of initial virological suppression and subsequent virological failure after initiating highly active antiretroviral therapy: the impact of aboriginal ethnicity and injection drug use

Objectives:

To compare rates of initial virological suppression and subsequent virological failure by Aboriginal ethnicity after starting highly active antiretroviral therapy (HAART).

Methods:

We conducted a retrospective cohort study of antiretroviral-naïve HIV-patients starting HAART in January 1999-June 2005 (baseline), followed until December 31, 2005 in Alberta, Canada. We compared the odds of achieving initial virological suppression (viral load <500 copies/mL) by Aboriginal ethnicity using logistic regression and, among those achieving suppression, rates of virological failure (the first of two consecutive viral loads > 1000 copies/mL) by Aboriginal ethnicity using cumulative incidence curves and Cox proportional hazards models. Sex, injection drug use as an HIV exposure category (IDU), baseline age, CD4 cell count, viral load, calendar year, and HAART regimen were considered as potential confounders.

Results:

Of 461 study patients, 37% were Aboriginal and 48% were IDUs; 71% achieved initial virological suppression and were followed for 730.4 person-years. After adjusting for confounding variables, compared to non-Aboriginals with other exposures, the odds of achieving initial virological suppression were lower for Aboriginal IDUs (odds ratio (OR)=0.33, 95% CI=0.19-0.60, p=0.0002), non-Aboriginal IDUs (OR=0.30, 95% CI=0.15-0.60, p=0.0006), and Aboriginals with other exposures (OR=0.38, 95% CI=0.21-0.67, p=0.0009). Among those achieving suppression, Aboriginals experienced higher virological failure rates ≥1 year after suppression (hazard ratio=3.35, 95% CI=1.68-6.65, p=0.0006).

Conclusions:

Future research should investigate adherence among Aboriginals and IDUs treated with HAART and explore their treatment experiences to assess ways to improve outcomes.

Referral rate to oncologists and its variation by hospital for colorectal cancer patients

BACKGROUND

Recent population-based studies in Alberta, Canada, found that approximately 50% of patients with stage III colon or stages II/III rectal adenocarcinoma did not receive guideline-recommended treatment (surgery plus chemotherapy or chemoradiation); a primary reason was not having an oncologist consult. We assessed the relationship between the hospital where the surgery was performed and the probability of a patient not having an oncologist consult.

METHODS

All patients diagnosed with stage III colon or stage II/III rectal adenocarcinoma between 2002 and 2005 in Alberta who had surgery were identified from the Alberta Cancer Registry and included in the study. Multivariable logistic regression modeling with hospitals as random effects was used to estimate cancer-type-specific odds ratios of not having an oncologist consult for each hospital, adjusted for age, sex, and comorbidities, relative to the overall nonconsultation rate.

RESULTS

Overall, 21% of stage III colon, 25% of stage II rectal, and 13% of stage III rectal adenocarcinoma patients did not have an oncologist consult. Rates varied appreciably across hospitals and between cancer types within hospitals, even after the case-mix adjustment (adjusted odds ratios of nonconsultation ranged from 0.4 to 8.1). Small hospitals that performed 12 or fewer surgeries had nearly 100% consultation rates.

CONCLUSIONS

The variation in oncologist-consult rates, particularly for stage II rectal cancer patients, is concerning. We are presenting the findings to the surgical community and discussing interventions to improve oncologist-consult rates.

Adherence to treatment guidelines in stage II/III rectal cancer in Alberta, Canada

AIMS

Evidence suggests that pre- and/or postoperative treatment benefits patients with stage II/III rectal cancer. This study aimed to quantify treatment patterns and adherence to treatment guidelines, and to identify barriers to having a consultation with an oncologist and barriers to receiving treatment in stage II/III rectal cancer, in a publicly funded medical care system.

MATERIALS AND METHODS

Patients with surgically treated stage II/III rectal adenocarcinoma, diagnosed from 2002 to 2005 in Alberta, a Canadian province with a population of 3 million, were included. Demographic and treatment information from the Alberta Cancer Registry were linked to data from electronic medical records, hospital discharge data and the 2001 Canadian Census. The study outcomes were 'not having an oncologist consultation' and 'not receiving guideline-based treatment'. The relative risks of the two outcomes in association with patient characteristics were estimated using multivariable log-binomial regression.

RESULTS

Of a total of 910 surgically treated stage II/III rectal adenocarcinoma patients, 748 (82%) had a consultation with an oncologist and 414 (45.5%) received treatment. Pre-/post-surgical treatment modalities and timing varied; 96 (10.5%) received neoadjuvant treatment only, 389 (42.7%) received adjuvant treatment only, 119 (13.1%) received both, and 306 (33.6%) had surgery alone. Factors related to not having a consultation with an oncologist included older age, co-morbidities, cancer stage II and region of residence. Older age was the most significantly associated factor with not receiving treatment (relative risk=2.23; 95% confidence interval: 1.89, 2.64).

CONCLUSIONS

Disparities exist in the receipt of treatment in stage II/III rectal cancer. Factors such as age, region of residence and stage should not be barriers to consulting an oncologist to discuss or receive treatment. The reasons for these disparities need to be identified and addressed.

Glucose-lowering agents and cancer mortality rates in type 2 diabetes: assessing effects of time-varying exposure

AIMS/HYPOTHESIS

We explored the relationship between glucose-lowering agents and cancer mortality rates in type 2 diabetes patients, hypothesising a decreased risk of cancer mortality with metformin use and a dose-risk gradient for insulin therapy.

METHODS

This was a population-based cohort study using administrative data from Saskatchewan Health, Canada. We identified new users of metformin or sulfonylureas from 1 January 1991 to 31 December 1996, with follow-up until death, departure from the province or 31 December 1999. Cox regression analyses were used to estimate the HR of death from cancer, accounting for time-varying exposure to metformin, sulfonylurea, and exogenous insulin therapy.

RESULTS

We identified 10,309 new users of metformin or sulfonylurea. The average follow-up was 5.4 (1.9) years, during which 407 (4.0%) cancer deaths occurred. Adjusting for age, sex and chronic disease score, the adjusted HR for metformin use was 0.80 (95% CI 0.65-0.98) compared with sulfonylurea monotherapy users. Adjusted HRs for subsequent insulin use were 2.22 (0.99-5.00), 3.33 (2.26-4.89) and 6.40 (4.69-8.73) for <3, 3 to 11 and > or = 12 insulin dispensations/year, respectively, compared with patients not on insulin. We observed a similar risk gradient among the sub-cohort of new insulin users.

CONCLUSIONS/INTERPRETATION

Our results support previous reports of a decreased risk of cancer outcomes associated with metformin use relative to sulfonylurea monotherapy. We also provide new evidence of a gradient of cumulative insulin dispensations and cancer mortality rates.

Clinical features of cases of influenza A (H1N1)v in Osaka prefecture, Japan, May 2009

This report describes the clinical characteristics of influenza A(H1N1)v virus infection in Osaka. By the end of May, 171 cases had been reported in Osaka. Most patients were from one school. No patient had a serious underlying medical condition.Clinical symptoms were mild and resembled those of seasonal influenza. The sensitivity of the rapid antigen test was 77%. Antivirals were given to the majority of the cases. Early antiviral treatment may have shortened the duration of fever.

Epidemiology of influenza A(H1N1)v virus infection in Japan, May - June 2009

Between 9 May and 4 June 2009, a total of 401 laboratory-confirmed cases of influenza A(H1N1)v virus were reported in Japan, from 16 of the 47 Japanese prefectures. The two areas most affected were Osaka prefecture and Kobe city where outbreaks in high schools occurred leading to school closures. To date all cases have had symptoms consistent with seasonal influenza and no severe or fatal cases have been reported.

The virtues of a deliberately mis-specified disease model in demonstrating a gene-environment interaction

OBJECTIVES

This study seeks to assess the impact of measurement errors in cumulative exposure on estimates of a gene-environment interaction in a nested case-control study in occupational epidemiology. In the approach considered here, exposure intensity is assessed at the group level and the exposure duration individually (both with error). Genetic susceptibility is assumed to be known exactly. Differences in "gene" are assumed to affect disease risk only in exposed subjects.

METHODS

Three data analysis strategies were considered: one using a correctly specified disease model (exposure and exposure-gene interaction), and two using mis-specified disease models, one with "gene" as the only risk factor ("gene-only" model) and the other with main effects of both gene and exposure along with their interaction ("full" model).

RESULTS

In simulations, estimates of the gene-environment interaction based on the correctly specified disease model were greatly attenuated and power was diminished appreciably even when errors in exposure were modest. Significant associations were detected more frequently in the gene-only model when errors in exposure were large. When the "full" mis-specified model was fitted to the simulated data, it yielded erratic estimates. This is illustrated in an analysis of the interaction of cumulative exposure to organophosphate pesticides and paraoxonase gene on the risk of chronic neuropsychological effects among farmers who dip sheep.

CONCLUSION

If "gene" contributes to disease risk only in the presence of exposure, the existence of the gene-environment interaction can be efficiently inferred from a deliberately mis-specified "gene-only" disease model in nested case-control studies.