Spray dried progesterone formulations for carrier free dry powder inhalation

Low oral absorption and extensive first pass metabolism of progesterone is reported for many oral formulations which warrants investigation into other routes of administration. It is the aim of this study to investigate the generation of inhaled formulations of progesterone though a spray drying approach with a focus on how spray drying impacts the physicochemical properties of progesterone. Formulations of progesterone with L-leucine and hydroxypropyl methylcellulose acetate succinate (HPMCAS) are reported to this aim. X-ray diffraction, spectroscopy and thermal analysis were used to characterise these formulations and confirmed that progesterone crystallises as the Form II polymorph during spray drying regardless of the solvent used. The resultant formulations showed higher aqueous solubility than progesterone Form I starting material and the addition of HPMCAS was shown to temporarily enable a supersaturated state. Thermal analysis was used to show that the Form II polymorph was sensitive to transformation to Form I during heating. The addition of L-leucine to the formulations reduced the temperature for the polymorphic transformation by ∼ 10 °C. However, when HPMCAS was added to the formulation, the Form II polymorph was prevented from transforming to the Form I polymorph. Cascade impaction was used to determine the aerosol performance of the spray dried powders and showed promising lung deposition profiles (mass median aerodynamic diameter 5 µm) with significant variation depending on the organic solvent used and the ratio of organic to aqueous phase in the feedstock. However, further optimisation of formulations was required to direct more progesterone into the alveolar regions. The addition of HPMCAS was seen to increase the alveolar deposition and therefore formed a formulation with a lower fine particle fraction and mass median aerodynamic diameter. The most suitable formulation for inhalation was formed from a 50:50 acetone:water mixture and showed an ED, FPF and FPD of 81.7%, 44.5% and 7.3 mg respectively. Therefore, HPMCAS is suggested as a suitable excipient to increase solubility, prevent polymorphic transformation and improve inhalation properties of spray dried progesterone formulations. This study highlights the use of spray drying to form inhalable progesterone powders with higher solubility which may broaden the application of this medicine

Chitosan-GSNO nanoparticles : a positive modulator of drought stress tolerance in soybean

Funding: This research was supported by Basic Science Research Program through the National Research Foundation (NRF) of Korea funded by the Ministry of Education (RS-2023-00245922) to Prof. Byung-Wook Yun and by the Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (2021R1I1A1A01049154) to Dr. Bong-Gyu Mun.Background : Chitosan biopolymer is an emerging non-toxic and biodegradable plant elicitor or bio-stimulant. Chitosan nanoparticles (CSNPs) have been used for the enhancement of plant growth and development. On the other hand, NO is an important signaling molecule that regulates several aspects of plant physiology under normal and stress conditions. Here we report the synthesis, characterization, and use of chitosan-GSNO nanoparticles for improving drought stress tolerance in soybean. Results: The CSGSNONPs released NO gas for a significantly longer period and at a much lower rate as compared to free GSNO indicating that incorporation of GSNO in CSNPs can protect the NO-donor from rapid decomposition and ensure optimal NO release. CS-GSNONPs improved drought tolerance in soybean plants reflected by a significant increase in plant height, biomass, root length, root volume, root surface area, number of root tips, forks, and nodules. Further analyses indicated significantly lower electrolyte leakage, higher proline content, higher catalase, and ascorbate peroxidase activity, and reduction in MDA and H2O2 contents after treatment with 50 μM CS-GSNONPs under drought stress conditions. Quantitative real-time PCR analysis indicated that CS-GSNONPs protected against drought-induced stress by regulating the expression of drought stress-related marker genes such as GmDREB1a, GmP5CS, GmDEFENSIN, and NO-related genes GmGSNOR1 and GmNOX1. Conclusions : This study highlights the potential of nano-technology-based delivery systems for nitric oxide donors to improve plant growth, and development and protect against stresses.Publisher PDFPeer reviewe

A novel study on bean common mosaic virus accumulation shows disease resistance at the initial stage of infection in Phaseolus vulgaris

Accurate and early diagnosis of bean common mosaic virus (BCMV) in Phaseolus vulgaris tissues is critical since the pathogen can spread easily and have long-term detrimental effects on bean production. The use of resistant varieties is a key factor in the management activities of BCMV. The study reported here describes the development and application of a novel SYBR Green-based quantitative real-time PCR (qRT-PCR) assay targeting the coat protein gene to determine the host sensitivity to the specific NL-4 strain of BCMV. The technique showed high specificity, validated by melting curve analysis, without cross-reaction. Further, the symptoms development of twenty advanced common bean genotypes after mechanical BCMV-NL-4 infection was evaluated and compared. The results showed that common bean genotypes exhibit varying levels of host susceptibility to this BCMV strain. The YLV-14 and BRS-22 genotypes were determined as the most resistant and susceptible genotypes, respectively, in terms of aggressiveness of symptoms. The accumulation of BCMV was analyzed in the resistant and susceptible genotypes 3, 6, and 9 days following the inoculation by the newly developed qRT-PCR. The mean cycle threshold (Ct) values showed that the viral titer was significantly lower in YLV-14, which was evident in both root and leaf 3 days after the inoculation. The qRT-PCR thus facilitated an accurate, specific, and feasible assessment of BCMV accumulation in bean tissues even in low virus titers, allowing novel clues in selecting resistant genotypes in the early stages of infection, which is critical for disease management. To the best of our knowledge, this is the first study of a successfully performed qRT-PCR to estimate BCMV quantification

Delivery of costimulatory blockade to lymph nodes promotes transplant acceptance in mice

The lymph node (LN) is the primary site of alloimmunity activation and regulation during transplantation. Here, we investigated how fibroblastic reticular cells (FRCs) facilitate the tolerance induced by anti-CD40L in a murine model of heart transplantation. We found that both the absence of LNs and FRC depletion abrogated the effect of anti-CD40L in prolonging murine heart allograft survival. Depletion of FRCs impaired homing of T cells across the high endothelial venules (HEVs) and promoted formation of alloreactive T cells in the LNs in heart-transplanted mice treated with anti-CD40L. Single-cell RNA sequencing of the LNs showed that anti-CD40L promotes a Madcam1+ FRC subset. FRCs also promoted the formation of regulatory T cells (Tregs) in vitro. Nanoparticles (NPs) containing anti-CD40L were selectively delivered to the LNs by coating them with MECA-79, which binds to peripheral node addressin (PNAd) glycoproteins expressed exclusively by HEVs. Treatment with these MECA-79-anti-CD40L-NPs markedly delayed the onset of heart allograft rejection and increased the presence of Tregs. Finally, combined MECA-79-anti-CD40L-NPs and rapamycin treatment resulted in markedly longer allograft survival than soluble anti-CD40L and rapamycin. These data demonstrate that FRCs are critical to facilitating costimulatory blockade. LN-targeted nanodelivery of anti-CD40L could effectively promote heart allograft acceptance

신경 수지상 발달에 대한 신경교 기여를 연구하기 위한 연구 플랫폼 구축

glia, neuronal dendrites, golgiGlia are increasingly regarded to play an active role in the nervous system and no longer viewed as mere providers of passive and supportive responses to neurons. Glia contribute to nervous system both directly, by wrapping the axon of neurons, and indirectly, by regulating surrounding environment. While the glial effect on axonal development or maintenance is well studied, less is known about glial contribution to neuronal dendrites. Herein, I showed that the development of stereotypical neuronal dendrites depends on the existence of healthy and morphologically stable glia. I established an applied research platform using existing methods. Because of the diffi-culty to study the effects of non-cell autonomous influences in other model systems, I made the best use of the advantages of Drosophila model system. An independent enhancer-driven cellular marker allows to observe the alterations of neurons when glia are specifically manipu-lated. Furthermore, caspase-LOV system enable to control the degeneration process spatio-temporally in Drosophila. Taken together, the results show the diverse possibilities of glia contribution to neuronal dendritesprohibitionList of Contents Abstract ·································································································· i List of contents ······················································································· ii List of figures ·························································································· vi Ⅰ. INTRODUCTION 1 1.1 Glia is indispensable for neuronal development. ····················································· 1 1.2 Manipulation of glial integrity via light-controlled glial degeneration in Drosophila model system ··························································································· 2 II. MATERIALS AND METHODS ....................................................................................4 III. RESULTS 8 3.1 Changes in neuronal dendrites upon glial degeneration ........................................ 8 3.2 Changes in neuronal dendrites via blocking the function of glial Golgi .................. 15 IV. DISCUSSION .......................................................................................................... 29 V. REFERENCES .......................................................................................................... 31 VI. SUMMARY (국문요약) ............................................................................................ 33글리아는 신경계에 존재하는 비-신경 세포인데, 일반적으로는 주로 신경 세포의 신호 전달이나 항상성 등 기능적인 측면에서 보조적인 역할을 하거나 신경 세포가 제자리에서 기능할 수 있도록 하거나 영양분을 공급함으로써 신경 세포의 전반적인 발달 과정에 관여하며 도움을 주는 것으로 알려져 있다. 그러나 최근에는 글리아가 수동적으로 단순히 도와주는 역할을 할 뿐만 아니라 신경계에서 조금 더 자발적으로 기능을 한다는 인식이 생겨나고 있다. 또한 신경계 질환의 메커니즘에도 관여한다는 것에 대한 연구 결과도 많아지고 있다. 이렇듯, 더 이상 신경계에 대한 본질적인 이해와 신경계 질환에 대한 치료 방안을 찾기 위해서는 신경 세포뿐만 아니라 글리아에 대한 연구도 필수적으로 함께 이루어져야 한다. 글리아는 주로 신경 세포와 시냅스의 주변부에서 존재하며 기능을 하지만, 신경 세포의 축삭 돌기를 감싸고 있음으로써 물리적인 접촉을 하고 있고, 이와 관련하여 글리아와 신경 세포의 축삭 돌기에 관한 연구는 활발히 이루어지고 있다. 그러나 신경 수지상 돌기는 시냅스를 형성하고 신호를 주고받는 중요한 역할을 함에도 불구하고 글리아에 의해 보호받지 못한 채 외부로 노출되어 있고, 축색 돌기에 비해 글리아와의 관계성에 대한 연구는 비교적 적게 이루어지고 있다. 이러한 이유로 인하여 이번 연구에서는 글리아가 신경세포의 수지상 돌기에 미치는 영향에 대해서 알아보고자 하였다. 글리아가 신경 세포의 수지상 돌기에 어떤 영향을 미치는지 알아보기 위해서 빛으로 활성화시킬수 있는 ‘Caspase-LOV’ 시스템을 이용하여 글리아에서 의도적으로 세포 사멸 신호를 유도하고, 글리아가 악화되어 감에 따라 신경 세포의 수지상 돌기에서 어떤 변화가 나타나는지 관찰해 보았다. 그 결과, 글리아의 세포막이 망가지고 신호의 세기도 일부분 감소하였고, 이로 인한 신경 세포에 미치는 알아보기 위해 수지상 돌기를 분석하는 sholl analysis를 실시하였더니, 교차점의 수가 줄어든 것을 확인 할 수 있었다. 글리아가 신경 세포의 수지상 돌기에 영향을 줄 수 있다는 사실을 확인하였고, 조금 더 자세한 메커니즘을 알아보고자 하였다. ‘Caspase-LOV’ 활성화에 의하여 글리아에서 관찰된 가장 큰 변화는 바로 세포막의 손상이었다. 또한 망가진 글리아가 신경 세포에 미칠 수 있는 영향은 물리적인 손상으로 인한 것뿐만 아니라 신호 전달에도 문제가 생겼을 것이라고 생각하였다. 다양한 세포 소기관 중에서 이 두 가지 부분에 모두 관여할 수 있는 것이 골지다. 골지는 원형질막 공급에 관하여 중심이 되는 기능을 하고 있으며, 소포체 전달을 통해 신호를 전달 할 수도 있다. 그렇다면 골지에 의한 신호전달을 막아보고 뉴런에 미치는 영향을 알아보기 위해 글리아에서 분비 경로에 관한 인자인 CrebA의 전사 레벨을 조절하는 nej (CBP in human)를 RNAi를 통해 막아 보았다. 그 결과, glia에서 골지가 거의 사라지거나 잘 보이지 않았으며, 글리아의 세포막 신호도 매우 약해지고 모양이 망가졌다. 이 때, 신경 세포의 수지상 돌기에서는 어떤 변화가 있는지 확인하기 위해 sholl analysis를 실시하였더니 교차점의 수가 세포체 근처에서 거의 20% 이상 증가하였다. 그러나 CrebA의 경우, 분비 경로뿐만 아니라 관여하는 부분들이 매우 많기 때문에 글리아와 신경 세포에서 나타난 변화들이 정말 골지에 의한 것인지 정확하게 알 수 없었다. 그래서 조금 더 특정 짓기 위하여 ER에서 골지로 분비되는 경로에 관여하는 Rab1의 발현 레벨을 낮춘 후, 글리아와 신경 세포에서의 변화들을 관찰하였다. 이 때도 역시 glia의 골지가 거의 사라져 관찰되지 않았고, 세포막의 intensity도 매우 낮아졌음을 확인할 수 있었다. 신경 세포의 수지상 돌기에서도 변화가 보였는데 이는 글리아에서 nej의 레벨을 낮추었을 때와는 사뭇 다른 변화 패턴을 보였다. Sholl analysis 결과 커브가 세포체 중심쪽인 왼쪽으로 살짝 이동하는 모습을 확인할 수 있었다. 또한, 글리아는 신경 세포처럼 형태가 원형 모양이 아니다. 그렇기 때문에 필요한 물질이나 세포 소기관이 적시 적소에 위치하는 것이 중요한데 이러한 것들의 이동은 운동성 관련 단백질에 의해 매개된다. 바깥쪽으로 나가는 방향의 물질 이동은 kinesin에 의해 매개되는데, 구성 성분인 kinesin light chain의 발현을 막았더니 글리아의 형태가 일부 바뀌는 것을 확인하였고, 신경 세포의 수지상 돌기도 일부분 감소하는 듯한 모습을 보였다. 지금까지의 결과를 종합하여 보면 글리아에서의 변화가 신경 세포의 수지상 돌기에 어떠한 영향을 미칠 수 있다는 사실을 알았다. 지금까지의 데이터들은 글리아가 기여하는 부분이 물리적인 형태 때문인지 혹은 분비하는 것에 문제가 생겨 글리아에서 신경 세포로 신호 전달이 제대로 이루어지지 않아 생기는 문제인지에 대해서 정확하게 알 수는 없지만 글리아가 망가지는 방법과 정도에 따라 신경 세포의 수지상 돌기가 변화는 패턴이 다르다는 것을 알 수 있었고, 메커니즘을 밝히기 위해서는 더 많은 연구가 필요하다.MasterdCollectio

Immigrant Assimilation and Labor Market Outcomes

In this dissertation, I examine immigrants’ integration into host societies by examining systematic patterns in the U.S. labor market. In the first two chapters, I study how differences in language and culture explain the formation of small business by highly educated immigrants and what implications that have for firms trying to identify the most productive workers in an increasingly global labor force; in the last chapter, I study another aspect of social bias by exploring how the September 11 terrorist attacks shaped labor market outcomes for subgroups of the immigrant population.In Chapter 1, I show that linguistic-cultural backgrounds of immigrants can lead to a systematic misallocation of scarce talent: highly educated, foreign-born workers more likely sort out of salaried work, and into self-employment, than otherwise similar U.S.-born individuals. This differential sorting can be theoretically understood as a rational, but flawed, response to the difficulties of credibly signaling capabilities—the cultural distance between the employer and the candidate generates noisy signals, when precise signaling is more critical for applicants to more demanding jobs. Using surveys representative of the U.S. population and measuring cultural mismatch with “linguistic distance”, I find evidence consistent with this theory: not only the highly educated—who apply to more demanding jobs—but also the linguistically distant—who send noisier signals of ability—disproportionately sort into self-employment; immigrants who have culturally assimilated or who are surrounded by co-ethnics are less likely to exhibit such pattern. Furthermore, I show that immigrants’ English language deficit, among other potential drivers, does not, in and of itself, explain the differential sorting. This suggests that the systematic sorting pattern appears to reflect inefficient allocation of talent.In Chapter 2, I further discuss the implications of findings from Chapter 1. My empirical analyses suggest an important role for cultural frictions in the labor market and therefore, inability for firms to correctly identify the productive workers. Awareness of the phenomenon can, in principle, allow firms to better harness the untapped talent pool of highly educated immigrants sorting into self-employment—the hidden gems. I provide suggestions for how firms should adjust their hiring practices as well as estimate for how much firms may be able to benefit by solving the hidden gems problem.In Chapter 3, I examine how discrimination arising from preferences manifests itself in labor market outcomes across different minority groups over time. I exploit an exogenous shock in taste-based bias towards a subset of the immigrant group arising from the September 11 terrorist attacks: individuals who may appear to be Middle Eastern. By using a difference-in-differences approach based on a worker panel data, I provide suggestive evidence confirming previous studies, finding a negative effect of 9/11 on immigrants’ labor market outcomes. My results further suggest that there may potentially be heterogeneous effects associated with educational attainment, where the less well educated are increasingly worse off relative to the more educated. I partly ascribe this to the heterogeneous effect of occupational discrimination, where the less well educated increasingly sort into less complex jobs over time. I discuss alternative channels that may drive my results.While I study labor market imperfections in the context of immigrant workers in the U.S., the findings of my studies can be applied more broadly to better understand how social biases affect economic outcomes of minority groups. Given that there are particularly pronounced social divides between an immigrant and a non-immigrant, studying the experiences of immigrants provide a unique vantage point to examine the effect of labor market discrimination. I hope to contribute to expanding our understanding for how social factors such as language, culture and preferences importantly drive matching of workers to firms in the labor market, generating systematic and persistent patterns of occupational segregation

A short review: Comparisons of high-throughput phenotyping methods for detecting drought tolerance

Drought is a major threat worldwide for crop production, especially due to the rapid climate changes. Current drought solutions involve improving irrigation system, rainwater harvesting, damming, cloud seeding, and changes of cultivation methods. Despite effective, each solution has economic, environmental, and temporal drawbacks. Among all solutions, the most effective, inexpensive and manageable method is the use of drought-tolerant cultivars via plant breeding. However, conventional plant breeding is a time-consuming and laborious task, especially for phenotypic data acquisition of target traits of numerous progenies. Highthroughput phenotyping (HTP) is a recently developed method and has potential to overcome the mentioned issues. HTP offers massive, accurate, rapid, and automatic data acquisition in the breeding procedure and can be a breakthrough for developing drought resistant/tolerant cultivars. This study introduces various methods of HTP to detect drought stress, which can accelerate the breeding processes of drought-tolerant cultivars to provide helpful guidelines for breeders and researchers to choose appropriate methods

Silicon Effects on the Root System of Diverse Crop Species Using Root Phenotyping Technology

Roots play an essential function in the plant life cycle, as they utilize water and essential nutrients to promote growth and plant productivity. In particular, root morphology characteristics (such as length, diameter, hairs, and lateral growth) and the architecture of the root system (spatial configuration in soil, shape, and structure) are the key elements that ensure growth and a fine-tuned response to stressful conditions. Silicon (Si) is a ubiquitous element in soil, and it can affect a wide range of physiological processes occurring in the rhizosphere of various crop species. Studies have shown that Si significantly and positively enhances root morphological traits, including root length in rice, soybean, barley, sorghum, mustard, alfalfa, ginseng, and wheat. The analysis of these morphological traits using conventional methods is particularly challenging. Currently, image analysis methods based on advanced machine learning technologies allowed researchers to screen numerous samples at the same time considering multiple features, and to investigate root functions after the application of Si. These methods include root scanning, endoscopy, two-dimensional, and three-dimensional imaging, which can measure Si uptake, translocation and root morphological traits. Small variations in root morphology and architecture can reveal different positive impacts of Si on the root system of crops, with or without exposure to stressful environmental conditions. This review comprehensively illustrates the influences of Si on root morphology and root architecture in various crop species. Furthermore, it includes recommendations in regard to advanced methods and strategies to be employed to maintain sustainable plant growth rates and crop production in the currently predicted global climate change scenarios