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Can improving access to mobile extension improve agricultural productivity? Recent evidence suggests both significant and insignificant ways in which SMS-based agricultural information could affect farming outcomes. It is unclear if variations in the programs’ design or the methodological challenges in evaluating the programs cause wide-ranging impacts. Extension hotline services provide rapid, unambiguous information by agricultural experts over the phone, tailored to time- and crop-specific shocks. Using methods from experimental economics, we randomly distributed the hotline number to generate exogenous variation in the access to farming information. We conducted our study among 300 farmers in the South Indian state of Karnataka. Our results show that eliminating informational inefficiencies increases farmers’ average yields for a high-stakes pigeon pea crop that faced adverse aggregate shock. The impact on the yield is through the adoption of cost-effective and improved farming practices. However, we do not observe any effect on the crops that were not affected by the shock. Our findings reveal that advisory recommendations customized to time- and crop-specific shocks are associated with a greater impact on agricultural productivity.

Effects of Bacillus thuringiensis ( Bt ) cotton are at the forefront of an intense debate on the benefits of genetically modified (GM) crops among smallholder farmers in developing countries. Existing studies fail to control for confounders, selection bias, or cultivation bias from preferential treatment in the initial adoption phase. Addressing these concerns in this paper, I examine the impact of Bt cotton employing an unbalanced panel fixed-effects model of a crop yield and profit function on newly collected plot-level data in the most recent decade. Results show that Bt cotton yields have stagnated, have a null effect on profits, and have become more sensitive to pest pressure in the most recent decade. Though many studies have demonstrated higher crop yield and profit gains in the first decade of Bt cotton adoption that raised the average returns to the technology, the second decade shows convergence in benefits, which raises obvious questions about the prospect of GM technology. Since Bt cotton is the only GM crop technology widely adopted by smallholder farmers, the findings of this paper contribute to the broader public debate on the future of agricultural biotechnology.

The human umbilical cord (UC) is an attractive source of mesenchymal stem cells (MSCs) with unique advantages over other MSC sources. They have been isolated from different compartments of the UC but there has been no rigorous comparison to identify the compartment with the best clinical utility. We compared the histology, fresh and cultured cell numbers, morphology, proliferation, viability, stemness characteristics and differentiation potential of cells from the amnion (AM), subamnion (SA), perivascular (PV), Wharton's jelly (WJ) and mixed cord (MC) of five UCs. The WJ occupied the largest area in the UC from which 4.61 ± 0.57 x 106 /cm fresh cells could be isolated without culture compared to AM, SA, PV and MC that required culture. The WJ and PV had significantly lesser CD40+ non-stem cell contaminants (26-27%) compared to SA, AM and MC (51-70%). Cells from all compartments were proliferative, expressed the typical MSC-CD, HLA, and ESC markers, telomerase, had normal karyotypes and differentiated into adipocyte, chondrocyte and osteocyte lineages. The cells from WJ showed significantly greater CD24+ and CD108+ numbers and fluorescence intensities that discriminate between MSCs and non-stem cell mesenchymal cells, were negative for the fibroblast-specific and activating-proteins (FSP, FAP) and showed greater osteogenic and chondrogenic differentiation potential compared to AM, SA, PV and MC. Cells from the WJ offer the best clinical utility as (i) they have less non-stem cell contaminants (ii) can be generated in large numbers with minimal culture avoiding changes in phenotype, (iii) their derivation is quick and easy to standardize, (iv) they are rich in stemness characteristics and (v) have high differentiation potential. Our results show that when isolating MSCs from the UC, the WJ should be the preferred compartment, and a standardized method of derivation must be used so as to make meaningful comparisons of data between research groups.

Secretome derived from human amniotic fluid stem cells (AFSC-S) is rich in soluble bioactive factors (SBF) and offers untapped therapeutic potential for regenerative medicine while avoiding putative cell-related complications. Characterization and optimal generation of AFSC-S remains challenging. We hypothesized that modulation of oxygen conditions during AFSC-S generation enriches SBF and confers enhanced regenerative and cardioprotective effects on cardiovascular cells. We collected secretome at 6-hourly intervals up to 30 h following incubation of AFSC in normoxic (21%O 2 , nAFSC-S) and hypoxic (1%O 2 , hAFSC-S) conditions. Proliferation of human adult cardiomyocytes (hCM) and umbilical cord endothelial cells (HUVEC) incubated with nAFSC-S or hAFSC-S were examined following culture in normoxia or hypoxia. Lower AFSC counts and richer protein content in AFSC-S were observed in hypoxia. Characterization of AFSC-S by multiplex immunoassay showed higher concentrations of pro-angiogenic and anti-inflammatory SBF. hCM demonstrated highest proliferation with 30h-hAFSC-S in hypoxic culture. The cardioprotective potential of concentrated 30h-hAFSC-S treatment was demonstrated in a myocardial ischemia–reperfusion injury mouse model by infarct size and cell apoptosis reduction and cell proliferation increase when compared to saline treatment controls. Thus, we project that hypoxic-generated AFSC-S, with higher pro-angiogenic and anti-inflammatory SBF, can be harnessed and refined for tailored regenerative applications in ischemic cardiovascular disease.

Gestational diabetes mellitus (GDM) has been associated with an increased risk of maternal and neonatal morbidity. The Wharton’s jelly (WJ) of the umbilical cord (UC) is a useful indicator of the deleterious effects of hyperglycemia on fetal tissues as it represents the fetus embryologically, physiologically and genetically. We studied WJ mesenchymal stem cells (hWJSCs) from UC from mothers without GDM (Normal; n = 3); insulin-controlled GDM mothers (GDMi; n = 3) and diet-controlled GDM mothers (GDMd; n = 3)]. Cell proliferation, stemness markers, telomerase, osteogenic and chondrogenic differentiation, antioxidant enzymes and gene expression for mitochondrial function (ND2, TFAM, PGC1α, and NDUFB9) were significantly lower in GDMi-hWJSCs and GDMd-hWJSCs compared to normal hWJSCs (P < 0.05). On the other hand, cell cycle inhibitors (p16, p21, p27) and p53 were remarkably up-regulated in GDMi-hWJSCs and GDMd-hWJSCs compared to normal hWJSCs. The results from this study confirmed that maternal hyperglycemia even though managed with insulin or diet, induced changes in the properties of the WJ and its cells. These changes may also be observed in fetal tissues and if true, prevention of the onset of gestational diabetes should be a priority over management. Generation of tissues that simulate those of the fetus such as pancreatic and cardiovascular cells from GDM-hWJSCs by direct differentiation or via induced pluripotent stem cell reprogramming provide possible platforms to evaluate the effects of glucose on specific fetal organ.

Background Keloid formation occurs in Caucasian, African, and Asian populations and is a severe psychosocial burden on patients. There is no permanent treatment for this problem as its pathogenesis is not properly understood. Furthermore, differences in keloid behavior between ethnic groups are not known. It has been hypothesized that keloids behave like benign tumors because of their uncontrolled growth. The present study evaluated the tumoricidal properties of human Wharton’s jelly stem cell-conditioned medium (hWJSC-CM) on fresh Asian keloid cells (AKCs). Methods Human Wharton’s jelly stem cells (hWJSCs) and AKCs were isolated based on our previous methods. hWJSCs and human skin fibroblasts (HSF) (controls) were used to collect hWJSC-CM and HSF-conditioned medium (HSF-CM). AKCs were treated with hWJSC-CM and HSF-CM in vitro and in vivo in a human keloid xenograft SCID mouse model. The inhibitory effect of hWJSC-CM on AKCs was tested in vitro using various assays and in vivo for attenuation/abrogation of AKC tumors created in a xenograft mouse model. Results qRT-PCR analysis showed that the genes FN1, MMP1, and VCAN were significantly upregulated in AKCs and ANXA1, ASPN, IGFBP7, LGALS1, and PTN downregulated. AKCs exposed to hWJSC-CM in vitro showed significant decreases in cell viability and proliferation, increases in Annexin V-FITC+ cell numbers, interruptions of the cell cycle at Sub-G1 and G2/M phases, altered CD marker expression, downregulated anti-apoptotic-related genes, and upregulated pro-apoptotic and autophagy-related genes compared to controls. When AKCs were administered together with hWJSC-CM into immunodeficient mice there were no keloid tumors formed in 7 mice ( n  = 10) compared to the untreated control mice. When hWJSC-CM was injected directly into keloid tumors created in mice there were significant reductions in keloid tumor volumes and weights in 30 days. Conclusions hWJSC-CM inhibited the growth of AKCs in vitro and in xenograft mice, and it may be a potential novel treatment for keloids in the human. The specific molecule(s) in hWJSC-CM that induce the anti-keloid effect need to be identified, characterized, and tested separately in larger preclinical and clinical studies.

The current treatments used for osteoarthritis from cartilage damage have their disadvantages of donor site morbidity, complicated surgical interventions and risks of infection and graft rejection. Recent advances in tissue engineering have offered much promise in cartilage repair but the best cell source and in vitro system have not as yet been optimised. Human bone marrow mesenchymal stem cells (hBMSCs) have thus far been the cell of choice. However, we derived a unique stem cell from the human umbilical cord Wharton's jelly (hWJSC) that has properties superior to hBMSCs in terms of ready availability, prolonged stemness characteristics in vitro, high proliferation rates, wide multipotency, non-tumorigenicity and tolerance in allogeneic transplantation. We observed enhanced cell attachment, cell proliferation and chondrogenesis of hWJSCs over hBMSCs when grown on PCL/Collagen nanoscaffolds in the presence of a two-stage sequential complex/chondrogenic medium for 21 days. Improvement of these three parameters were confirmed via inverted optics, field emission scanning electron microscopy (FESEM), MTT assay, pellet diameters, Alcian blue histology and staining, glycosaminglycans (GAG) and hyaluronic acid production and expression of key chondrogenic genes (SOX9, Collagen type II, COMP, FMOD) using immunohistochemistry and real-time polymerase chain reaction (qRT-PCR). In separate experiments we demonstrated that the 16 ng/ml of basic fibroblast growth factor (bFGF) present in the complex medium may have contributed to driving chondrogenesis. We conclude that hWJSCs are an attractive stem cell source for inducing chondrogenesis in vitro when grown on nanoscaffolds and exposed sequentially first to complex medium and then followed by chondrogenic medium.

PurposeThe empirical literature on climate change and agriculture does not adequately address the issue of potential endogeneity between climatic variables and agriculture, which makes their estimates unreliable. This paper aims to investigate the relationships between climate change and agriculture and test the potential reverse causality and endogeneity of climatic variables to agriculture.Design/methodology/approachThis study introduces a geographical instrument, longitude and latitude, for temperature to assess the impact of climate change on agriculture by estimating regression using IV-two-stage least squares method over annual panel data for 60 countries for the period of 1999-2011. The identification and F-statistic tests are used to choose and exclude the instrument. The inclusion of some control variables is supposed to reduce the omitted variable bias.FindingsThe study finds a negative relationship between temperature and agriculture. Surprisingly, the magnitude of the coefficient on temperature is mild, at least 20 per cent, as compared to previous studies, which may be because of the use of the instrumental variable (IV), which is also supported by an alternative robust measure when estimated across different regions.Practical implicationsThe study provides strong implications for policymakers to confront climate change, which is an impending danger to agriculture. In designing effective policies and strategies, policymakers should focus not only on crop production but also on other agricultural activities such as livestock production and fisheries, in addition to national and international socio-economic and geopolitical dynamics.Originality/valueThis paper contributes to the growing literature in at least four aspects. First, empirical settings introduce an innovative geographical instrument, Second, it includes a wider set of control variables in the analysis. Third, it extends previous studies by involving agriculture value addition. Finally, the effects of temperature and precipitation on a single aggregate measure, agriculture value addition, are separately investigated.

There is a growing body of literature about the impacts of Bacillus thuringiensis (Bt) cotton in developing countries. While many studies show remarkable benefits for farmers, there are also reports that question these results. Most previous studies consider impacts in deterministic terms, neglecting existing variability. Here we explain the main factors influencing the agronomic and economic outcomes. Apart from differences in pest pressure and patterns of pesticide use, germplasm effects can play an important role. Theoretical arguments are supported by empirical evidence from India. Better understanding of impact variability can help explain some of the paradoxes in the recent controversy over genetically modified crops.

Human Wharton’s jelly stem cells (hWJSCs) are multipotent stem cells that are extensively employed in biotechnology applications. However, the impact of simulated lunar microgravity (sμG) on the growth, differentiation, and viability of this cell population is incompletely characterized. We aimed to determine whether acute (72 h) exposure to sμG elicited changes in growth and lineage differentiation in hWJSCs and if putative changes were maintained once exposure to terrestrial gravity (1.0 G) was restored. hWJSCs were cultured under standard 1.0 G conditions prior to being passaged and cultured under sμG (0.16 G) using a random positioning machine. Relative to control, hWJSCs cultured under sμG exhibited marked reductions in growth but not viability. Cell population expression of characteristic stemness markers (CD 73, 90, 105) was significantly reduced under sμG conditions. hWJSCs had 308 significantly upregulated and 328 significantly downregulated genes when compared to 1.0 G culture conditions. Key markers of cell replication, including MKI67 , were inhibited. Significant upregulation of osteocyte–chondrocyte lineage markers, including SERPINI1, MSX2, TFPI2, BMP6, COMP, TMEM119, LUM, HGF, CHI3L1 and SPP1 , and downregulation of cell fate regulators, including DNMT1 and EZH2 , were detected in sμG-exposed hWJSCs. When returned to 1.0 G for 3 days, sμG-exposed hWJSCs had accelerated growth, and expression of stemness markers increased, approaching normal (i.e. 95%) levels. Our data support earlier findings that acute sμG significantly reduces the cell division potential of hWJSCs and suggest that acute sμG-exposure induces reversible changes in cell growth accompanied by osteocyte–chondrocyte changes in lineage differentiation.