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To investigate the dynamics of stomata, transpiration, and photosynthesis under varying light intensities and CO2 conditions during leaf development, the light response and CO2 response of stomatal conductance (gsw), transpiration rate (Tr), and net photosynthetic rate (Pn) were observed for rice leaves at different days after leaf emergence (DAE). The results showed that (1) as photosynthetically active radiation (PAR) increased, leaf gsw, Tr, and Pn initially increased rapidly and linearly, followed by a more gradual rise to maximum values, and then either stabilized or showed a declining trend. The maximum gsw, Tr, and Pn were smaller and occurred earlier for old leaves than for young leaves. The gsw, Tr, and Pn all exhibited a linear decreasing trend with increasing DAE, and the rate of decrease slowed down with the reduction in PAR; (2) as the CO2 concentration (Ca) increased, gsw and Tr decreased gradually to a stable minimum value, while Pn increased linearly and slowly up to the maximum and then kept stable or decreased. The gsw, Tr, and Pn values initially kept high and then decreased with the increase of DAE. These results contribute to understanding the dynamics in gsw, Tr, and Pn during rice leaf growth and their response to varied light and CO2 concentration conditions and provide mechanistic support to estimate dynamic evapotranspiration and net ecosystem productivity at field-scale and a larger scale in paddy field ecosystems through the upscaling of leaf-level stomatal conductance, transpiration, and photosynthesis.

Compared with 454 sequencing technology, short-read sequencing (e.g., Illumina) technology generates sequences of high accuracy, but limited length (500 bp) is challenging. The ammonia monooxygenase subunit A (amoA) gene of ammonia-oxidizing archaea (AOA), which plays a crucial part in the nitrification process, is such a gene. By providing a full overview of the community of a functional microbial guild, 16S ribosomal ribonucleic acid (rRNA) gene sequencing could overcome this problem. However, it remains unclear how 16S rRNA primer selection influences the quantification of relative abundance and the identification of community composition of nitrifiers, especially AOA. In the present study, a comparison was made between the performance of primer pairs 338F-806R, 515F-806R, and 515F-907R to a shotgun metagenome approach. The structure of nitrifier communities subjected to different long-term organic matter amendment and water management protocols was assessed. Overall, we observed higher Chao1 richness diversity of soil total bacteria by using 515F-806R compared to 338F-806R and 515F-907R, while higher Pielou’s evenness diversity was observed by using 515F-806R and 515F-907R compared to 338F-806R. The studied primer pairs revealed different performances on the relative abundance of Thaumarchaeota, AOB, and NOB. The Thaumarchaeota 16S rRNA sequence was rarely detected using 338F-806R, while the relative abundances of Thaumarchaeota detected using 515F-806R were higher than those detected by using 515F-907R. AOB showed higher proportions in the 338F-806R and 515F-907R data, than in 515F-806R data. Different primers pairs showed significant change in relative proportion of NOB. Nonetheless, we found consistent patterns of the phylotype distribution of nitrifiers in different treatments. Nitrosopumilales (NP) and Nitrososphaerales (NS) clades were the dominant members of the AOA community in soils subject to controlled irrigation, whereas Ca. Nitrosotaleales (NT) and NS clades dominated the AOA community in soils subject to flooding irrigation. Nitrospira lineage II was the dominant NOB phylotype in all samples. Overall, ideal 16S rRNA primer pairs were identified for the analysis of nitrifier communities. Moreover, NP and NT clades of AOA might have distinct environmental adaptation strategies under different irrigation treatments.

IntroductionCystic lymphangioma is a benign malformation tumor of the lymphatic system. Its location is variable, and mesocolic localization remains extremely rare.Case presentationWe report a case of right mesocolon giant cystic lymphangioma in a previously healthy 14-year-old boy who was successfully managed through a minimally invasive laparoscopic excision. The patient presented with 8 months of dull abdominal pain, sporadic, located on the peri-umbilicus, exacerbated for a month. An abdominal computed tomography (CT) revealed a large, multiseptated cystic mass on the right mesocolon. Right mesocolic excision using a laparoscope was performed on this patient. He was discharged on the fifth day without complications. Recurrence was not detected in three months of follow-up.ConclusionCystic lymphangiomas in the mesocolon are rare benign neoplasms that pose diagnostic challenges. Complete resection is the optimal option for diagnostic confirmation and recurrence prevention. Laparoscopic surgery is feasible for children with mesocolic lymphangioma.

Regenerating brain defects after traumatic brain injury (TBI) still remains a significant difficulty, which has motivated interest in 3D printing to design superior replacements for brain implantation. Collagen has been applied to deliver cells or certain neurotrophic factors for neuroregeneration. However, its fast degradation rate and poor mechanical strength prevent it from being an excellent implant material after TBI. In the present study, we prepared 3D-printed collagen/silk fibroin/hypoxia-pretreated human umbilical cord mesenchymal stem cells (HUCMSCs)-derived exosomes scaffolds (3D-CS-HMExos), which possessed favorable physical properties suitable biocompatibility and biodegradability and were attractive candidates for TBI treatment. Furthermore, inspired by exosomal alterations resulting from cells in different external microenvironments, exosomes were engineered through hypoxia stimulation of mesenchymal stem cells and were proposed as an alternative therapy for promoting neuroregeneration after TBI. We designed hypoxia-preconditioned (Hypo) exosomes derived from HUCMSCs (Hypo-MExos) and proposed them as a selective therapy to promote neuroregeneration after TBI. For the current study, 3D-CS-HMExos were prepared for implantation into the injured brains of beagle dogs. The addition of hypoxia-induced exosomes further exhibited better biocompatibility and neuroregeneration ability. Our results revealed that 3D-CS-HMExos could significantly promote neuroregeneration and angiogenesis due to the doping of hypoxia-induced exosomes. In addition, the 3D-CS-HMExos further inhibited nerve cell apoptosis and proinflammatory factor (TNF-α and IL-6) expression and promoted the expression of an anti-inflammatory factor (IL-10), ultimately enhancing the motor functional recovery of TBI. We proposed that the 3D-CS-loaded encapsulated hypoxia-induced exosomes allowed an adaptable environment for neuroregeneration, inhibition of inflammatory factors and promotion of motor function recovery in TBI beagle dogs. These beneficial effects implied that 3D-CS-HMExos implants could serve as a favorable strategy for defect cavity repair after TBI.

The regeneration of brain tissue poses a great challenge because of the limited self-regenerative capabilities of neurons after traumatic brain injury (TBI). For this purpose, 3D-printed collagen/silk fibroin/secretome derived from human umbilical cord blood mesenchymal stem cells (HUCMSCs) pretreated with bFGF scaffolds (3D-CS-bFGF-ST) at a low temperature were prepared in this study. From an in vitro perspective, 3D-CS-bFGF-ST showed good biodegradation, appropriate mechanical properties, and good biocompatibility. In regard to vivo, during the tissue remodelling processes of TBI, the regeneration of brain tissues was obviously faster in the 3D-CS-bFGF-ST group than in the other two groups (3D-printed collagen/silk fibroin/secretome derived from human umbilical cord blood mesenchymal stem cells (3D-CS-ST) group and TBI group) by motor assay, histological analysis, and immunofluorescence assay. Satisfactory regeneration was achieved in the two 3D-printed scaffold-based groups at 6 months postsurgery, while the 3D-CS-bFGF-ST group showed a better outcome than the 3D-CS-ST group.

To investigate the dynamics of stomata, transpiration, and photosynthesis under varying light intensities and CO2 conditions during leaf development, the light response and CO2 response of stomatal conductance (gsw), transpiration rate (Tr), and net photosynthetic rate (Pn) were observed for rice leaves at different days after leaf emergence (DAE). The results showed that (1) as photosynthetically active radiation (PAR) increased, leaf gsw, Tr, and Pn initially increased rapidly and linearly, followed by a more gradual rise to maximum values, and then either stabilized or showed a declining trend. The maximum gsw, Tr, and Pn were smaller and occurred earlier for old leaves than for young leaves. The gsw, Tr, and Pn all exhibited a linear decreasing trend with increasing DAE, and the rate of decrease slowed down with the reduction in PAR; (2) as the CO2 concentration (Ca) increased, gsw and Tr decreased gradually to a stable minimum value, while Pn increased linearly and slowly up to the maximum and then kept stable or decreased. The gsw, Tr, and Pn values initially kept high and then decreased with the increase of DAE. These results contribute to understanding the dynamics in gsw, Tr, and Pn during rice leaf growth and their response to varied light and CO2 concentration conditions and provide mechanistic support to estimate dynamic evapotranspiration and net ecosystem productivity at field-scale and a larger scale in paddy field ecosystems through the upscaling of leaf-level stomatal conductance, transpiration, and photosynthesis. [ABSTRACT FROM AUTHOR]