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1.
J Hazard Mater ; 401: 123391, 2021 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-32653795

RESUMO

This study evaluated the microbial safety and antibiotic resistance risks of a sustainable ecological farm under large-scale open-air composting (OC) and green composting toilet systems (CT). Samples of livestock manure, compost, soil, vegetables, and rainwater were analysed to determine the best treatment of wastes and risk assessment of land application. Results showed that pathogenic bacteria (PB) in livestock manure was significantly greater than that in the surrounding topsoil, while the distribution of bacteria resistant to amoxicillin (AMX), tetracycline (TC), and amoxicillin-tetracycline (AMX- TC) was the opposite through long-term resistance selection pressure. E. coli and Enterococcus were the dominant pathogens in feces and surrounding soil, respectively, and AMX-resistant bacteria dominated soil, compost, and vegetable samples. Overall, while OC may significantly increase antibiotic resistance and effectively remove fecal PB, CT offers faster consumption with greater antibiotic resistant bacteria (ARB) removal but more PB. Moreover, PB and ARB were concentrated in mature compost, soil in planting areas, vegetables, and rainwater. In farm soil and vegetables, AMX-resistant and AMX-TC-resistant bacterial communities displayed similar composition. These findings may explain the main pathways of PB transmission, migration and accumulation of ARB in farms, and the potential risks to human health through the food chain.

2.
Food Chem ; 339: 127859, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-32829244

RESUMO

The objective of this study was to investigate the effects of four commercial lactic acid bacteria (LAB), namely L. acidophilus, L. casei, L. helveticus and L. plantarum, on the phenolic profiles, antioxidant capacities and flavor profiles of jujube juices prepared from two crop varieties (Ziziphus Jujuba cv. Muzao and Hetian). Results showed that both jujube juices were excellent matrices for LAB growth with more than 11 log CFU/mL of viable counts at the end of fermentation. LAB fermentation dramatically increased total phenolic content, while decreased total flavonoid content of jujube juices. However, antioxidant capacities based on DPPH and FRAP methods were significantly improved by LAB fermentation and positively correlated with caffeic acid and rutin contents. Furthermore, a total of 74 volatile compounds were identified and increased in total content by LAB fermentation, which resulted in 22 and 19 new flavor volatiles formation in Muzao juice and Hetian juice, respectively.

3.
Nanoscale Res Lett ; 15(1): 205, 2020 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-33146756

RESUMO

It is challenging to explore and prepare polyoxometalates-based nanomaterials (PNMs) with controllable morphologies and diversiform components. Herein, 3d-4f metals are introduced into isopolyoxometalates and Anderson-type polyoxometalates, CeCdW12 nanoflower and EuCrMo6 microflaky have been fabricated respectively. A series of control experiments are carried out to identify the impact factors on the rare morphologies in PNMs. Furthermore, upon excitation at 396 nm, the emission spectrum of EuCrMo6 displays five prominent f - f emitting peaks at 674, 685, 690, 707, and 734 nm that are assigned to Eu3+ 5D0 → 7FJ (J = 0, 1, 2, 3, 4) transitions. Meanwhile, the VSM results show that the Cr+3 ions in EuCrMo6 display anti-ferromagnetic interactions when the temperature is lower than - 17.54 K. After rising temperature, this material exhibits paramagnetic property. This work opens up strategies toward the brand new morphologies and components of PNMs, endowing this kind of material with new functions.

4.
Biomed Res Int ; 2020: 3049302, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33145344

RESUMO

The present study was to investigate the effect of mesenteric lymph duct drainage on lung inflammatory response, histological alteration, and endothelial cell apoptosis in septic rats. Animals were randomly assigned into four groups: control, sham surgery, sepsis, and sepsis plus mesenteric lymph drainage. We used the colon ascendens stent peritonitis (CASP) procedure to induce the septic model in rats, and mesenteric lymph drainage was performed with a polyethylene (PE) catheter inserted into mesenteric lymphatic. The animals were sacrificed at the end of CASP in 6 h. The mRNA expression levels of inflammatory mediators were measured by qPCR, and the histologic damage were evaluated by the pathological score method. It was found that mesenteric lymph drainage significantly reduced the expression of TNF-α, IL-1ß, and IL-6 mRNA in the lung. Pulmonary interstitial edema and infiltration of inflammatory cells were alleviated by mesenteric lymph drainage. Moreover, increased mRNA levels of TNF-α, IL-1ß, IL-6 mRNA, and apoptotic rate were observed in PMVECs treated with septic lymph. These results indicate that mesenteric lymph duct drainage significantly attenuated lung inflammatory injury by decreasing the expression of pivotal inflammatory mediators and inhibiting endothelial apoptosis to preserve the pulmonary barrier function in septic rats.

5.
Artigo em Inglês | MEDLINE | ID: mdl-33148801

RESUMO

Duchenne muscular dystrophy (DMD) is a fatal muscle disorder characterized by cycles of degeneration and regeneration of multinucleated myofibers and pathological activation of a variety of other muscle-associated cell types. The extent to which different nuclei within the shared cytoplasm of a myofiber may display transcriptional diversity and whether individual nuclei within a multinucleated myofiber might respond differentially to DMD pathogenesis is unknown. Similarly, the potential transcriptional diversity among nonmuscle cell types within dystrophic muscle has not been explored. Here, we describe the creation of a mouse model of DMD caused by deletion of exon 51 of the dystrophin gene, which represents a prevalent disease-causing mutation in humans. To understand the transcriptional abnormalities and heterogeneity associated with myofiber nuclei, as well as other mononucleated cell types that contribute to the muscle pathology associated with DMD, we performed single-nucleus transcriptomics of skeletal muscle of mice with dystrophin exon 51 deletion. Our results reveal distinctive and previously unrecognized myonuclear subtypes within dystrophic myofibers and uncover degenerative and regenerative transcriptional pathways underlying DMD pathogenesis. Our findings provide insights into the molecular underpinnings of DMD, controlled by the transcriptional activity of different types of muscle and nonmuscle nuclei.

6.
J Mol Neurosci ; 2020 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-33159672

RESUMO

Alzheimer's disease (AD) poses a significant threat to human life and health. The intraneuronal accumulation of ß-amyloid (Aß) plaques in the brains of AD patients results in neuronal cell death, which is a key factor that triggers multiple changes in the pathogenesis of AD. The inhibition of Aß-induced neuronal cell death may potentially help in the intervention and treatment of AD. Our previous study reported that tumor necrosis factor α-induced protein 1 (TNFAIP1) is induced by and promotes Aß25-35-induced neurotoxicity in mouse neuronal cells, but the roles and regulatory mechanisms of TNFAIP1 are still largely unknown. In this study, our experimental results show that TNFAIP1 and p-TNFAIP1 (phosphorylation of TNFAIP1 at Ser280) are overexpressed in the neurons of the cortex and hippocampus in the brains of APP/PS1 mice, and the transcription factor NF-κB is involved in the Aß-induced upregulation of TNFAIP1. Moreover, our results suggest that TNFAIP1 contributes to the Aß-induced reactive oxygen species (ROS) production, decreased mitochondrial membrane potential (∆Ψm), and neuronal cell death in human SH-SY5Y cells. We further revealed that Aß increases the binding of TNFAIP1 to RhoB, and knockdown of RhoB attenuates the TNFAIP1-induced apoptosis of human SH-SY5Y cells. These data suggest that TNFAIP1 is closely associated with AD pathogenesis, and overexpression of TNFAIP1 in the neurons of the brains of AD patients plays a role in apoptosis, at least in part, via RhoB signaling.

7.
J Org Chem ; 2020 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-33225704

RESUMO

The manganese porphyrin-catalyzed C-H bond hydroxylation and amidation of equilenin acetate developed by Breslow and his co-worker have been investigated with density functional theory (DFT) calculations. The hydroxylation of C(sp2)-H bond of equilenin acetate leading to the 6-hydroxylated product is more favorable than the hydroxylation of C(sp3)-H bond of equilenin acetate, leading to the 11ß-hydroxylation product. The computational results suggest that the C(sp2)-H bond hydroxylation of equilenin acetate undergoes an oxygen-atom-transfer mechanism, which is more favorable than the C(sp3)-H bond hydroxylation undergoing the hydrogen-atom-abstraction/oxygen-rebound (HAA/OR) mechanism by 1.6 kcal/mol. That is why, the 6-hydroxylated product is the major product and the 11ß-hydroxylated product is the minor product. In contrast, the 11ß-amidated product is the only observed product in manganese porphyrin-catalyzed amidation reaction. The benzylic amidation undergoes a hydrogen-atom-abstraction/nitrogen-rebound (HAA/NR) mechanism, in which hydrogen atom abstraction is followed by nitrogen rebound, leading to the 11ß-amidated product. The benzylic C(sp3)-H bond amidation at the C-11 position is more favorable than aromatic amidation at the C-6 position by 4.9 kcal/mol. Therefore, the DFT computational results are consistent with the experiments that manganese porphyrin-catalyzed C-H bond hydroxylation and amidation of equilenin acetate have different regioselectivities.

8.
J Phys Chem B ; 2020 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-33226245

RESUMO

Nanoparticle (NP)-mediated therapies are promising tools for the treatment of a wide range of diseases, including stroke and cancer, due to the outstanding performance they have shown for specifically targeting diseased sites. Importantly, the coupling of stiffness and shape of NPs has a significant influence on transportation via blood flow and internalization by targeted cells. Nevertheless, the underlying mechanism of this coupling effect on the endocytosis of NPs remains largely unexplored, resulting from a lack of clear measurement of stiffness for NPs in experiments, as well as the complexity of the endocytosis process. To overcome the above challenges, coarse-grained simulations, which can provide abundant nanoscale details and precise control of mechanical properties of NPs, were implemented to study the stiffness and shape dependence of the endocytosis of spherocylindrical NPs. To understand the coupling effect between shape and stiffness of NPs for membrane wrapping, coarse-grained molecular dynamics (CGMD) models with explicit bond, area, volume, and bending stiffness control were constructed for spherocylindrical NPs with identical volumes but different aspect ratios (ARs) ranging from 1.3 to 11.0. Results indicate that the endocytosis time of NPs increases as the aspect ratio increases due to both the increasing surface area and decreasing wrapping rate resulting from the decreasing contact perimeter. Moreover, soft and long NPs with AR = 11.0 exhibit wormlike wiggling in contrast to rodlike penetration of the stiff, enlarging the contact area and facilitating the endocytosis process. In addition, three types of NP fates are differentiated: full endocytosis, full endocytosis with membrane damage, and partial endocytosis with membrane damage. Among those patterns, damages/defects on the membrane can promote wrapping of NPs, although extra time is needed to close the defect after endocytosis. In summary, our results help gain a deeper understanding of the underlying mechanism of endocytosis of NPs with respect to geometry and particle stiffness, providing a useful guideline for designs of nanoparticles that can be implemented in next-generation nanoparticle-assisted therapy.

9.
Pathol Res Pract ; 216(12): 153286, 2020 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-33197836

RESUMO

Anaplastic lymphoma kinase (ALK)-rearranged renal cell carcinoma (RCC) is a rare subtype of RCC with gene fusion involving ALK at 2p23. It was first included in the renal tumor classification system by WorldHealth organization (WHO) as a distinct emerging/provisional renal entity in 2016. To date, only a few cases of ALK-RCC have been reported. Here, we report an exceptional case of ALK-RCC in a 15-year-old girl and review the literature. The patient presented with gross hematuria and a tumor measured 7 cm × 6 cm was found in the left kidney by imaging examination. Then a laparoscopic radical nephrectomy combined with local lymph node dissection was performed. The pathologic stage of the tumor was pT1bN1Mx and postoperative pathology showed that the tumor corresponded to WHO/ISUP grade 3-4. Immunohistochemistry (IHC) demonstrated moderate nuclear expression of TFE3 protein. Interestingly, ALK gene rearrangement rather than TFE3 gene rearrangement was observed by fluorescence in situ hybridization (FISH). Now the girl is still alive without evidence of recurrence for 10 months follow-up. In conclusion, the positive expression of nuclear TFE3 in immunohistochemistry may be deceptive, the detection of ALK could be a diagnostic option if TFE3 was negative in FISH study. Large-scale and long-term studies are still needed to explore the biological behavior and molecular characteristic of ALK-RCC.

10.
Artigo em Inglês | MEDLINE | ID: mdl-33196445

RESUMO

Patient satisfaction is a key performance indicator of patient-centered care and hospital reimbursement. To discover the major factors that affect patient experiences is considered as an effective way to formulate corrective actions. A patient during his/her healthcare journey interacts with multiple health professionals across different service units. The health-related data generated at each step of the journey is a valuable resource for extracting actionable insights. In particular, self-reported satisfaction survey and the associated patient electronic health records play an important role in the hospital-patient interaction analysis. In this paper, we propose an interpretable machine learning framework to formulate the patient satisfaction problem as a supervised learning task and utilize a mixed-integer programming model to identify the most influential factors. The proposed framework transforms heterogeneous data into human-understandable features and integrates feature transformation, variable selection, and coefficient learning into the optimization process. Therefore, it can achieve desirable model performance while maintaining excellent model interpretability, which paves the way for successful real-world applications.

11.
Eur J Med Genet ; : 104101, 2020 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-33189936

RESUMO

N-ethylmaleimide-sensitive factor attachment proteins (NAP: NAPA and NAPB) play a role in Soluble N-ethylmaleimide-sensitive accessory protein receptor (SNARE) complex dissociation and recycling, associated with neuronal regulation and brain development and various severe early-onset epilepsies. Here, we report two patients from a Chinese family presenting with unexplained early-onset epileptic encephalopathies (EOEE) syndrome characterized by multifocal seizures, profound intellectual disability and global developmental delay. We identified the homozygous c.433-1G>A variant of the NAPB as the causative by trio-based exome sequencing. The novel splicing mutation in NAPB was third variant reported associated with EOEE syndrome. Our results gave further hints on the associations of variants in NAPB with EOEE and indicated that for patients with unexplained EOEE, the NAPB gene should be included into the data analysis from whole exome sequencing, which contributes to uncover more patients affected and rich the phenotypic spectrum.

12.
Chem Commun (Camb) ; 2020 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-33179640

RESUMO

The water oxidation reaction is the pivotal half-reaction for photo-/electro-catalytic water splitting. Fabrication of high-efficiency and robust water oxidation is essential to realize wide-scale artificial photosynthesis. Here, we report an efficient strategy to improve the water oxidation activity of iridium oxide by a nitrogen-coordination method. Due to the coordination effect, the iridium oxide can be well dispersed to generate ultra-small nanoparticles and the intrinsic activity can be improved for the water oxidation reaction. This study suggests that high-performance water oxidation catalysts can be constructed based on a nitrogen-coordination strategy.

13.
Exp Biol Med (Maywood) ; : 1535370220966767, 2020 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-33167690

RESUMO

Secondary intra- and extrahepatic bile duct dilatation is a very common condition that can be caused by several diseases. However, it has been rarely discussed in the specialized literature. Moreover, no distinct etiology can be determined in some cases, which hampers the diagnosis and treatment. Here, we discuss the etiological classification and treatment strategies of secondary intra- and extrahepatic bile duct dilatation based on an extensive literature review, as well as our experimental research and clinical experience. The etiology of secondary intra- and extrahepatic bile duct dilatation can be classified in different ways. From a clinicopathological perspective, it can be classified into obstruction-, lesion-, and compression-induced dilatation. Treatment varies depending on the cause. For example, endoscopic dilation or stenting is used for biliary strictures, laparoscopic choledochectomy for stone removal, and resection for cholangiocarcinoma.

14.
J Org Chem ; 2020 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-33161704

RESUMO

Four binuclear tridentate copper(I) complexes were synthesized based on the trans effect of the hybrid ligands. The catalytic performance and behavior of the prepared copper(I) complexes were evaluated in the carboxylative cyclization of propargylic amines with CO2. The combined use of copper(I) complexes and 1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD) provided a catalytic system for the synthesis of a wide range of oxazolidinones from various propargylic amines and CO2 under mild reaction conditions (room temperature-40 °C and 1 bar CO2). The key factor for the success of the protocol is the use of copper complexes possessing the quality of hemilabile properties between N-heterocyclic carbenes and nitrogen donors. NMR measurements, density functional theory (DFT) calculations, and previous reports for the coordination behavior of the nickel complexes support the existence of the trans effect between N-heterocyclic carbenes and nitrogen donors.

15.
Technol Forecast Soc Change ; : 120435, 2020 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-33162619

RESUMO

This paper evaluates the impact of COVID-19 media coverage in mitigating its spread in China during the early phase of the pandemic. We construct a provincial-level dataset on COVID-19 and link it with population mobility data, among other control variables, to estimate how media coverage mitigates the spread of COVID-19. Seemingly unrelated regressions are used to examine the simultaneous impact of media coverage on the number of new cases and close contacts. The results show that the effect of media coverage on COVID-19 transmission in China had an inverse-U curvature and was mediated by within- and across-province population mobility. Our simulation results indicate that COVID-19 media coverage in China was associated with a potential reduction of 394,000 cases and 1.4 million close contacts during January 19 and February 29, 2020. Our results also provide strong support for the use of contact tracing in mitigating COVID-19 transmission.

16.
Int J Med Sci ; 17(17): 2751-2762, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33162803

RESUMO

Background: To date, the effect of vasopressin on organ damages after acute mesenteric ischemia (MI) remains poorly understood. Aims: To investigate the effect of terlipressin, a selective vasopressin V1 receptor agonist, versus norepinephrine on the intestinal and renal injuries after acute MI, and to explore the underlying mechanism of terlipressin. Methods: Acute MI model was produced by clamping the superior mesenteric artery for 1 hour. Immediately after unclamping, terlipressin or norepinephrine was intravenously administered for 2 hours. Meanwhile, in vitro, RAW264.7 cells were treated with lipopolysaccharide or lipopolysaccharide+terlipressin. In addition, wortmannin was used to determine the role of phosphoinositide 3-kinase (PI3K)/ protein kinase B (Akt) pathway in the potential impacts of terlipressin. Results: MI led to severe hypotension, caused notable intestinal and renal impairments and resulted in high mortality, which were markedly improved by terlipressin or norepinephrine. Terlipressin increased mean arterial pressure, decreased intestinal epithelial cell apoptosis, inhibited the generation of M1 macrophage in intestinal and renal tissues, and hindered the release of inflammatory cytokines after MI. Moreover, in cultured macrophages, terlipressin reduced the mRNA level of specific M1 markers and the release of inflammatory cytokines caused by lipopolysaccharide challenge. Wortmannin decreased the expression of PI3K and Akt induced by terlipressin in cells and in tissues, and abolished the above protective effects conferred by terlipressin. Conclusions: Terlipressin or norepinephrine could effectively improve organ damages and mortality after acute MI. Terlipressin elevates blood pressure and inhibits intestinal epithelial apoptosis and macrophage M1 polarization via the PI3K/Akt pathway.

17.
Opt Express ; 28(23): 35158-35167, 2020 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-33182967

RESUMO

The field of soft robotics has been significantly advanced with the recent developments of pneumatic techniques, soft materials, and high-precision motion control. While comprehensive motions can be achieved by sophisticated soft robots, multiple coordinated pneumatic controls are usually required to achieve even the simplest motions. Furthermore, most soft robotics are lacking the ability to sense the environment and provide feedback to the pneumatic control system. In this work, we design a twining plant inspired soft-robotic spiral gripper that requires only one single pneumatic control to perform the twining motion and to firmly hold onto a target object. The soft-robotic spiral gripper has an embedded high-birefringence fiber optic twisting sensor to provide critical information, including twining angle, presence of external perturbation, and physical parameter of the target object. Furthermore, finite element analyses (FEA) in parametric studies of the spiral gripper are performed for module design optimization. The unique single pneumatic channel design enables easy manipulation of the soft spiral gripper with a maximum of 540° twining angle and allows a firm grip of a target object as small as 1-mm in diameter. The embedded fiber optic sensor provides useful information of the target object as well as the twining angle of the soft robotic spiral gripper with high twining angle sensitivity of 0.03nm. The unique fiber-optic sensor embedded single-channel pneumatic spiral gripper that is made from non-toxic silicone rubber allows parallel and soft gripping of elongated objects located in a confined area, which is an essential building block for twining and twisting motions in soft robot.

18.
Transl Stroke Res ; 2020 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-33140258

RESUMO

Intravenous administration of tissue-type plasminogen activator (IV tPA) therapy has long been considered a mainstay in ischemic stroke management. However, patients respond to IV tPA therapy unequally with some subsets of patients having worsened outcomes after treatment. In particular, diabetes mellitus (DM) is recognized as a clinically important vascular comorbidity that leads to lower recanalization rates and increased risks of hemorrhagic transformation (HT). In this short-review, we summarize the recent advances in understanding of the underlying mechanisms involved in post-IV tPA worsening of outcome in diabetic stroke. Potential pathologic factors that are related to the suboptimal tPA recanalization in diabetic stroke include higher plasma plasminogen activator inhibitor (PAI)-1 level, diabetic atherogenic vascular damage, glycation of the tPA receptor annexin A2, and alterations in fibrin clot density. While factors contributing to the exacerbation of HT in diabetic stroke include hyperglycemia, vascular oxidative stress, and inflammation, tPA neurovascular toxicity and imbalance in extracellular proteolysis are discussed. Besides, impaired collaterals in DM also compromise the efficacy of IV tPA therapy. Additionally, several tPA combination approaches developed from experimental studies that may help to optimize IV tPA therapy are also briefly summarized. In summary, more research efforts are needed to improve the safety and efficacy of IV tPA therapy in ischemic stroke patients with DM/poststroke hyperglycemia.

19.
J Infect Chemother ; 2020 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-33039268

RESUMO

INTRODUCTION: Data on comprehensive characterization of multidrug-resistant (MDR) Staphylococcus aureus (S. aureus) carriage in human immunodeficiency virus (HIV)-positive patients are limited. The objective of the present study is to determine the prevalence, risk factors, phenotypic and molecular characterization of MDR S. aureus isolated from HIV-positive population. METHODS: A cross-sectional study was conducted to determine the characteristics of MDR S. aureus nasal carriage among HIV-positive outpatients in an HIV clinic from June to August 2017. Nasal swabs and risk factor data of the enrolled HIV-positive outpatients were collected. Phenotypic and molecular characteristics of MDR and non-MDR S. aureus isolates were analyzed. Risk factors for nasal carriage with MDR S. aureus were estimated by logistic regression. The relationship between phenotypic and molecular characteristics of S. aureus isolates was assessed by the correspondence analysis. RESULTS: Overall, 1001 HIV-positive outpatients were included. The prevalence of MDR S. aureus nasal carriage was 15.18% (152/1001), and the proportion of multidrug resistance among S. aureus isolates was 60.08% (152/253). Having a history of respiratory tract infection was the risk factor for MDR S. aureus nasal carriage (adjusted odds ratio = 1.90, 95% confidence interval: 1.25-2.89). Multidrug resistance of S. aureus isolates was in good corresponding relationships with clonal complex (CC)5, CC15, CC59 and CC398. CONCLUSIONS: We found high burden of multidrug resistance among S. aureus isolated from HIV-positive outpatients, particularly in those who had upper respiratory tract infection. Moreover, CC59 and CC398 are highly related to multidrug resistance of S. aureus isolates.

20.
Adv Mater ; : e2002873, 2020 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-33058247

RESUMO

Second-harmonic generation (SHG) is a nonlinear optical process that can provide disease diagnosis through characterization of biological building blocks such as amino acids, peptides, and proteins. The second-order nonlinear susceptibility tensor χ(2) of a material characterizes its tendency to cause SHG. Here, a method for finding the χ(2) elements from polarization-resolved SHG microscopy in transmission mode is presented. The quantitative framework and analytical approach that corrects for micrometer-scale morphology and birefringence enable the determination and comparison of the SHG susceptibility tensors of ß- and γ-phase glycine microneedles. The maximum nonlinear susceptibility coefficients are d33  = 15 pm V-1 for the ß and d33  = 5.9 pm V-1 for the γ phase. The results demonstrate glycine as a useful biocompatible nonlinear material. This combination of the analytical model and polarization-resolved SHG transmission microscopy is broadly applicable for quantitative SHG material characterization and diagnostic imaging.

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