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Vascular mild cognitive impairment (VMCI) is an early and reversible stage of dementia. Volume differences in regional gray matter may reveal the development and prognosis of VMCI. This study selected 2 of the most common types of VMCI, namely, periventricular white matter hyperintensities (PWMH, n = 14) and strategic single infarctions (SSI, n = 10), and used the voxel-based morphometry method to quantify their morphological characteristics. Meanwhile, age- and sex-matched healthy volunteers were included (n = 16). All the participants were neuropsychologically tested to characterize their cognitive function and underwent whole-brain magnetic resonance imaging scanning. Our results showed that the volumes of the bilateral temporal lobes and bilateral frontal gray matter were obviously diminished in the PWMH group. The atrophy volume difference was 4,086 voxels in the left temporal lobe, 4,154 voxels in the right temporal lobe, 1,718 voxels in the left frontal lobe, and 1,141 voxels in the right frontal lobe (P ≤ 0.001). Moreover, the characteristics of the gray matter atrophy associated with the PWMH were more similar to those associated with Alzheimer’s disease than SSI, which further revealed the susceptibility for escalation from PWMH to dementia. In conclusion, PWMH patients and SSI patients have different morphological characteristics, which explain the different prognoses of VMCI.

Tuberculosis remains a large global disease burden for which treatment regimens are protracted and monitoring of disease activity difficult. Existing detection methods rely almost exclusively on bacterial culture from sputum which limits sampling to organisms on the pulmonary surface. Advances in monitoring tuberculous lesions have utilized the common glucoside [18F]FDG, yet lack specificity to the causative pathogenMycobacterium tuberculosis(Mtb) and so do not directly correlate with pathogen viability. Here we show that a close mimic that is also positron-emitting of the non-mammalianMtbdisaccharide trehalose – 2-[18F]fluoro-2-deoxytrehalose ([18F]FDT) – can act as a mechanism-based enzyme reporter in vivo. Use of [18F]FDT in the imaging ofMtbin diverse models of disease, including non-human primates, successfully co-optsMtb-specific processing of trehalose to allow the specific imaging of TB-associated lesions and to monitor the effects of treatment. A pyrogen-free, direct enzyme-catalyzed process for its radiochemical synthesis allows the ready production of [18F]FDT from the most globally-abundant organic18F-containing molecule, [18F]FDG. The full, pre-clinical validation of both production method and [18F]FDT now creates a new, bacterium-specific, clinical diagnostic candidate. We anticipate that this distributable technology to generate clinical-grade [18F]FDT directly from the widely-available clinical reagent [18F]FDG, without need for either bespoke radioisotope generation or specialist chemical methods and/or facilities, could now usher in global, democratized access to a TB-specific PET tracer.

Sleep deprivation leads to hippocampal injury. Proteostasis disturbance is an important mechanism linking sleep deprivation and hippocampal injury. However, identifying noninvasive imaging biomarkers for hippocampal proteostasis disturbance remains challenging. Amide proton transfer-weighted (APTw) imaging is a chemical exchange saturation transfer technique based on the amide protons in proteins and peptides. We aimed to explore the ability of APTw imaging in detecting sleep deprivation-induced hippocampal proteostasis disturbance and its biological significance, as well as its biological basis. In vitro, the feasibility of APTw imaging in detecting changes of the protein state was evaluated, demonstrating that APTw imaging can detect alterations in the protein concentration, conformation, and aggregation state. In vivo, the hippocampal APTw signal declined with increased sleep deprivation time and was significantly lower in sleep-deprived rats than that in normal rats. This signal was positively correlated with the number of surviving neurons counted in Nissl staining and negatively correlated with the expression of glucose-regulated protein 78 evaluated in immunohistochemistry. Differentially expressed proteins in proteostasis network pathways were identified in the hippocampi of normal rats and sleep-deprived rats via mass spectrometry proteomics analysis, providing the biological basis for the change of the hippocampal APTw signal in sleep-deprived rats. These findings demonstrate that APTw imaging can detect hippocampal proteostasis disturbance induced by sleep deprivation and reflect the extent of neuronal injury and endoplasmic reticulum stress.

Early life stress (ELS) is associated with an increased risk of developing depression and anxiety disorders. Disturbances of the neurobiological glutamatergic system are implicated in depression; however, the long-term effects of ELS on glutamate (Glu) metabolites remain unclear. Our study used 7T proton magnetic resonance spectroscopy (7T 1H MRS) to detect metabolic Glu in a rat model to investigate maternal deprivation (MD)-induced ELS. MD was established in Sprague-Dawley rats by periodic separation from mothers and peers. Changes in the hippocampal volume and Glu metabolism were detected by 7T 1H MRS after testing for depression-like behavior via open field, sucrose preference, and Morris water maze tests. Adult MD offspring exhibited depression-like behavior. Compared to the control, the MD group exhibited reduced ratio of central activity time to total time and decreased sucrose consumption (p < 0.05). MD rats spent less time in the fourth quadrant, where the platform was originally placed, in the Morris water maze test. According to 7T 1H MRS, hippocampus of MD rats had elevated Glu and glutamate + glutamine (Glu+Gln) levels compared with the control group hippocampi, but Gln, γ-aminobutyric acid (GABA), and glutamate + glutamine (Glu+Gln) in the prefrontal cortex of MD rats showed a downward trend. Depression-like behavior and cognition deficits related to ELS may induce region-specific changes in Glu metabolism in the prefrontal cortex and hippocampus. The novel, noninvasive 7T 1H MRS-identified associations between Glu levels and ELS may guide future clinical studies.

Human papillomaviruses (HPVs) cause a subset of head and neck squamous cell carcinomas (HNSCCs). Previously, we demonstrated that HPV16 oncogene E6 or E6/E7 transduction increases the abundance of O-linked β-N-acetylglucosamine (O-GlcNAc) transferase (OGT), but OGT substrates affected by this increase are unclear. Here, we focus on the effects of O-GlcNAcylation on HPV-positive HNSCCs. We found that upon HPV infection, Unc-51-like kinase 1 (ULK1), an autophagy-initiating kinase, is hyper-O-GlcNAcylated, stabilized, and linked with autophagy elevation. Through mass spectrometry, we identified that ULK1 is O-GlcNAcylated at Ser409, which is distinct from the previously reported Thr635/Thr754 sites. It has been demonstrated that PKCα mediates phosphorylation of ULK1 at Ser423, which attenuates its stability by shunting ULK1 to the chaperone-mediated autophagy (CMA) pathway. Using biochemical assays, we demonstrate that ULK1 Ser409Ser410 O-GlcNAcylation antagonizes its phosphorylation at Ser423. Moreover, mutations of Ser409A and its neighboring site Ser410A (2A) render ULK1 less stable by promoting interaction with the CMA chaperone HSC70 (heat shock cognate 70 kDa protein). Furthermore, ULK1-2A mutants attenuate the association of ULK1 with STX17, which is vital for the fusion between autophagosomes and lysosomes. Analysis of The Cancer Genome Atlas (TCGA) database reveals that ULK1 is upregulated in HPV-positive HNSCCs, and its level positively correlates with HNSCC patient survival. Overall, our work demonstrates that O-GlcNAcylation of ULK1 is altered in response to environmental changes. O-GlcNAcylation of ULK1 at Ser409 and perhaps Ser410 stabilizes ULK1, which might underlie the molecular mechanism of HPV-positive HNSCC patient survival.

Objectives: To evaluate the occurrence, abundance, distribution, nature and clinical significance of multi-nucleated giant cell (MGC) in esophageal cancer.Materials and methods: MGCs were examined with conventional pathology, immunohistochemistry and immunofluorescence in 107 esophageal cancer tissues. The findings were correlated to pathological diagnosis and clinical behavior of the cancers.Results: MGCs were identified in 31.7% (34/107) of the cases. MGCs were positive for CD11c, CD11b, CD32, CD16, HLA-DR and MMP9, and negative for CD163, CD206 and CD64 giving a molecular profile of proinflammatory M1 but not immunosuppressive M2. MGCs were significantly related to decreased lymph node metastasis (p = 0.011), low pTNM stage (p = 0.044), favorable survival (p = 0.04), squamous cell cancer type rather than other histopathological subtypes (p = 0.020) and associated to better differentiation (p = 0.063).Conclusions: MGCs belong to M1 macrophage and perform phagocytosis and scavenging of cancer cells that would benefit patients' survival and could serve as a prognostic marker.

BackgroundThe current diagnosis of Parkinson's disease (PD) is mainly based on the typical clinical manifestations. However, 60% dopaminergic neurons have died when the typical clinical manifestations occur. Predictive neurobiomarkers may help identify those PD patients having non-motor disorders or in different stage and achieving the aim of early diagnosis. Up to date, few if any neuroimaging techniques have been described useful for non-movement disorders diagnosis in PD patients. Here, we investigated the alteration of metabolites in PD patients in different stage of PD and non-motor symptoms including sleep, gastrointestinal and cognitive dysfunction, by using the 1H-MRS.MethodsA total of 48 subjects were included between 2017 and 2019: 37 PD (15 men, age 47–82 years) and 11 healthy people (8 men, age 49–74 years). All participants underwent MRI and multi-voxel 1H-MRS examination within 3 days in admission. Six kinds of metabolites, such as creatine (Cr), N-acetyl aspartate/creatine (NAA/Cr), N-acetyl aspartate/choline (NAA/Cho), choline/creatine (Cho/Cr), lipid/creatine (LL/Cr), and myo-Inositol/creatine ratio (mI/Cr) were tested among the PD group and the control groups. Statistical analyses and correlation analyses were performed by using SPSS. The p < 0.05 was considered statistically significant.ResultsCompared late PD group with a control group or early group, higher Cr ratio and lower NAA/Cr ratio were observed in the late PD group (p < 0.05). The mI/Cr in the late PD group was also lower than that in the early PD group (p < 0.05). Regarding the relationship between metabolites and NMS, Cho/Cr was higher in the sleep disorder group, whereas mI/Cr was lower in the gastrointestinal dysfunction group in comparison with the non-symptom groups. Moreover, Cr, Cho/Cr, mI/Cr, and LL/Cr were identified to have higher concentrations in the cognitive group in thalamus.ConclusionsProton magnetic resonance spectroscopy is an advanced tool to quantify the metabolic changes in PD. Three biomarkers (Cr, NAA/Cr, and mI/Cr) were detected in the late stage of PD, suggesting that these markers might be potential to imply the progression of PD. In addition, subgroups analysis showed that MRS of thalamus is a sensitive region for the detection of cognitive decline in PD, and the alteration of neurochemicals (involving Cr, Cho, mI, and LL) may be promising biomarkers to predict cognitive decline in PD.

Background: Early life stress (ELS) is associated with an increased risk of developing depression and anxiety disorders. Disturbances of the neurobiological glutamatergic system are implicated in depression; however, the long-term effects of early life stress on glutamate (Glu) metabolites remain unclear. Our study used 7T proton magnetic resonance spectroscopy (7T 1 HMRS) to detect metabolic Glu in a rat model to investigate maternal deprivation (MD)-induced ELS. Methods: MD was established in Sprague-Dawley rats by periodic separation from mothers and peers. Changes in the hippocampal volume and Glu metabolism were detected by 7T 1 HMRS after testing for depression-like behavior via open field, sucrose preference, and Morris water maze tests. Findings: Adult MD offspring exhibited depression-like behavior. Compared to control, the MD group exhibited reduced ratio of central activity time to total time and decreased sucrose consumption (18 ± 6 g vs. 31 ± 12 g, p = 0·02). MD rats spent less time in the fourth quadrant, where the platform was originally placed, in the Morris water maze test. According to 7T 1 HMRS, MD rats had elevated Glu and glutamate+glutamine (Glu+Gln) levels compared with the control group hippocampi, but Gln and gamma-aminobutyric acid (GABA), glutamate+glutamine (Glu+Gln) in the prefrontal cortex of MD rats showed a downward trend. Interpretation: Depression-like behavior and cognition deficits related to ELS may induce region-specific changes in Glu metabolism in the prefrontal cortex and hippocampus. The novel, noninvasive 7T 1 HMRS-identified associations between Glu levels and ELS may guide future clinical studies. Funding Statement: The Key Program of the National Natural Science Foundation of China, No. 30930027; Program of the National Natural Science Foundation of China, No. 60971075; Natural Science Foundation of Guangdong Province of China, Nos.S2011010005194 and 2015A030313444; Shantou University Scientific Research Foundation for the Doctoral Scholar of China, No.NTF10010; The Department of Education, Guangdong Government under the Top-tier University Development Scheme for Research and Control of Infectious Diseases of China, No. 2015034. Declaration of Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. Ethics Approval Statement: All procedures used in the study were reviewed and approved by the Ethics Committee of School of Medicine, Shantou University Medical College, and comply with the National Institutes of Health’s Guide for the Care and Use of Laboratory Animals (NIH publication no. 85-23, revised 1985). In the handling and care of all animals, we followed the international guiding principles for animal research, as stipulated by the World Health Organization (WHO) Chronicle (World Health Organization, 1985), as adopted by the Laboratory Animal Center, Shantou University Medical College.

Although social media are extensively employed in health communication promotion, their online and offline connection has rarely tested. This qualitatively study used a sample of 30 communication experts and health professionals to explore the role of social media in mitigating COVID-19 infections and its implications to people’s health in Zanzibar. The findings revealed that social media are powerful platforms in providing health awareness information for mitigating COVID-19 and these platforms have enabled people to understand local medicines used to reduce the COVID-19 infections. In addition, there is high connection between online health information and offline people’s health actions. Furthermore, Social media usage poses no threat to peoples’ health during pandemic, however, there is high risk to affect those who lack Internet media literacy. Although social media poses no threat to some Internet media literate users, digital media literacy should be provided to all people in order to use these platforms more useful in mitigating infected diseases without compromising public health in Zanzibar and Africa at large.

Background sequencing errors. Background mutant reads for each of 37 somatic SNVs (X-axes) are indicated by their absolute read number (panel A) and by their allele frequency (Panel B). Background variants are defined as the non-reference-specific and non-tumour-specific nucleotide at the position of the SNVs. The nucleotide variant with the highest read count is shown (in red) to illustrate the mismatch error rate at the positions mutated in primary tumour samples. All background variants (shown in red) were filtered out by our custom filter criteria and all variants listed as true cfDNA mutations had read counts well above these background levels (blue squares). (PDF 1561 kb)

Methyl glycopyranosides of glucose, galactose, and mannose, their 2,3-di-O-benzyl-protected derivatives, as well as the unprotected sugars react with p-methoxybenzaldehyde dimethyl acetal (3) and with benzaldehyde dimethyl acetal (7) as reagents in the presence of thiourea 1 or squaramide 2 as the organocatalyst to afford regioselectively 4,6-O-arylidenated derivatives 5 and 8. With an excess amount of 3 or 7, diarylidenated derivatives are also obtained. In situ formation of acetals of type 3 and 7 from corresponding aldehydes 10 and 13 in the presence of an orthoester and organocatalyst 1 or 2 can be used to generate 5 and 8 directly from the aldehydes. Some substrates also lead to mixed orthoesters with this procedure. The reaction courses are discussed.

The pressing global issue of food insecurity due to population growth, diminishing land and variable climate can only be addressed in agriculture by improving both maximum crop yield potential and resilience. Genetic modification is one potential solution, but has yet to achieve worldwide acceptance, particularly for crops such as wheat. Trehalose-6-phosphate (T6P), a central sugar signal in plants, regulates sucrose use and allocation, underpinning crop growth and development. Here we show that application of a chemical intervention strategy directly modulates T6P levels in planta. Plant-permeable analogues of T6P were designed and constructed based on a 'signalling-precursor' concept for permeability, ready uptake and sunlight-triggered release of T6P in planta. We show that chemical intervention in a potent sugar signal increases grain yield, whereas application to vegetative tissue improves recovery and resurrection from drought. This technology offers a means to combine increases in yield with crop stress resilience. Given the generality of the T6P pathway in plants and other small-molecule signals in biology, these studies suggest that suitable synthetic exogenous small-molecule signal precursors can be used to directly enhance plant performance and perhaps other organism function.

Sirtuins, comprised of seven members, protect cells from injury, possibly through different roles. In this study, we used two young rat optic nerve injury models to analyze the changes in Sirts 1-7 at different time points to better understand the role of sirtuins during optic nerve injury. Twelve-week-old adult male F344 rats (total n=42) were divided randomly into two groups. One group was subjected to optic nerve cut (ON-cut) and the other group was subjected to a peripheral nerve-optic nerve graft (PN-ON graft) on the left eye. At 1 and 3 days and 1, 2, and 4 weeks, rats were euthanized and retinas of both eyes were removed. Total RNA was extracted and first-strand cDNA was synthesized. Sirts 1-7 and housekeeping -actin quantitative real-time PCR were performed. The quantitative real-time PCR profile showed that sirtuin mRNAs in both groups increased following optic nerve injury with and without peripheral nerve grafting. Sirt1 mRNA increased rapidly, reaching its peak at 3 days after surgery. Sirts 2-7 showed an increasing trend and remained high through 4 weeks after surgery. Sirts 4 and 6 were the only Sirts that increased in number in the PN-graft group at 4 weeks after surgery, where neuronal survival should be higher. Our data indicate that Sirt1 and Sirts 2-7 may play different or complementary roles in optic nerve injury and that Sirts 4 and 6 may play a greater role than the remaining Sirts in axon regeneration.

2-O-Propargyl-substituted glycosyl donors and O-(2-azidobenzyl)-substituted acceptors having a vicinal hydroxy group readily underwent the click reaction. Intramolecular glycosidation with N-iodosuccinimide/trifluoromethansulfonic acid as the activating system afforded β-(1–3)- and α-(1–2)-linked disaccharides as part of 14-membered macrocycles. Descriptors for these reactions are proposed that consider the donor and acceptor attachment sites and the stereochemistry of the functional groups. Investigation of the influence of 2-O-linked 1-aryl-1,2,3-triazol-4-ylmethyl groups, as contained in the spacer, on the anomeric selectivity exhibited no anchimeric assistance. In addition, it was shown that the spacer group can be readily cleaved under Birch reduction conditions.

Adduct formation between alcohols as glycosyl acceptors and phenylsilicon trifluoride (PhSiF3) as catalyst permits acid-base-atalyzed glycosidations with O-glycosyl trichloroacetimidates as glycosyl donors. In this way, from various glycosyl donors and acceptors 1,2-trans- and some 1,2-cis-glycosides could be obtained with high anomeric selectivity. A preference for an intramolecular bimolecular nucleophilic substitution (SN2-type) reaction course with concomitant donor and acceptor activation is supported by the results.

Based on a pre-activation protocol, the stereoselectivity of oxazolidinone-protected amino sugar thioglycoside donors towards glycosylations can be controlled by additives. Either α- or β-selectivity could be obtained by changing additives. 2,4,6-Tri-tert-butylpyrimidine (TTBP) was the best β-directing additive, while thiophene worked as the best α-directing additive. The bifunctional additives such as tetrabutyl ammonium iodide (TBAI) afforded either α- or β-selectivity depending on the amount added. Poor α-­selectivity of some glycosylations without any additives was greatly improved by adding TBAI or thiophene.

Previously we showed that macrophage activation in the eye by intravitreal application of zymosan increased retinal ganglion cell (RGC) survival and axonal regeneration after optic nerve injury. It is known that the intrinsic ability of CNS neurons to survive and to regrow axons after optic nerve injury differs between developing and adult mammals. However, whether aged animals also differ in their ability to survive and regrow injured axons are not known. In this study we investigated whether the abilities of RGCs to survive and to regrow injured axons differed between rats aged 6-8, 60 and over 96 weeks, and whether macrophage responses in the eye were different at different ages. We found that the intrinsic viability of RGCs, as shown in vitro, was reduced in aged rats, but RGC viability after optic nerve injury in vivo was similar among rats of the different ages. The ability of RGCs to regrow injured axons into a peripheral nerve graft also remained similar between young and aged rats. Macrophage activation in the eye was confirmed to be beneficial and provided the basis for zymosan treatment-dependent RGC protection. However, reduced activation of macrophages in zymosan-treated eyes was seen in aged rats. Importantly, this reduced macrophage activation in aged rats led to a decreased level of RGC axonal regeneration when compared with that in young rats of the same treatment. Thus age influences the intrinsic viability of RGCs and the beneficial impact of macrophages on RGC axonal regeneration after optic nerve injury.

Diverse 2,3-oxazolidinone protected 2-amino-2-deoxy- d -glucose thioglycosides were prepared and studied as glycosyl donors at low temperature by BSM/Tf2O pre-activation protocol before the addition of glycosyl acceptors. The stereochemistry outcomes of a series of glycosylations were investigated. Different stereoselectivities of the coupling reactions were obtained, arising from the different protecting groups in the oxazolidinone donors. 4,6-Di-O-benzyl-N-benzyl-oxazolidinone protected thioglycoside donor 1c underwent glycosylation with general β-anomeric selectivity and the stereoselectivity could be also affected by glycosylation conditions.

Michael-type addition of thiolates to 2-nitro-d-glucal or to 2-nitro-d-galactal derivatives readily provides 2-deoxy-2-nitro-1-thioglycosides. Kinetic and thermodynamic reaction control permitted formation of either the α- or preferentially the β-anomers, respectively. Addition of achiral and chiral thiourea derivatives to the reaction mixture increased the reaction rate; the outcome is substrate-controlled. The 2-deoxy-2-nitro-1-thioglycosides are excellent glycosyl donors under arylsulfenyl chloride/silver triflate (ArSCl/AgOTf) activation, and they provide, anchimerically assisted by the nitro group, mostly β-glycosides.

To detect the expression of NGF, BDNF, NT-3 mRNA in the peripheral blood of patients with allergic rhinitis (AR). And to analyze the correlation between NGF, BDNF, NT-3 mRNA expression and the epidsode of rhinitis through Th-2 Hypothesis.This study was a group controlled trial. The expression of NGF, BDNF and NT-3 mRNA were tested by real-time quantitative RT-PCR and the concentrations of IL-4, IL-6, IL-10 and INF-alpha were tested by ELISA.The expression of NGF, BDNF and NT-3 mRNA in AR patients were 2.44, 4.46 and 1.78 times the amount of those in the healthy adults, respectively. The increased expression of NT-3 correlated positively with the scores of visual analog scale of AR. The concentrations of IL-4, IL-6 and IL-10, which were 2198 +/- 472 pg/mL, 9407 +/- 703 pg/mL and 3917 +/- 323 pg/mL respectively, were higher than those in the healthy adults. The concentration of INF-alpha was 2198 +/- 472 pg/mL and less than the healthy adults. The increased expressions of NGF, NT-3 were positively related to the increase of IL-4, IL-6 and IL-10.The expressions of NGF, BDNF and NT-3 mRNA in AR patients are higher than those in the healthy adults. NGF, BDNF and NT-3 may contribute to the pathogenesis of AR. Moreover, NGF and NT-3 may induce the episode of rhinitis through Th-2 Hypothesis.

To assess the expression of NGF, BDNF, NT-3 mRNA in the peripheral blood of patients with allergic rhinitis (AR). Meanwhile, to analysis whether the expression of NGF, BDNF, NT-3 mRNA correlate with the severity of rhinitis.This study is a group controlled trial, which takes the healthy adults as control group. The total RNA have been extracted from the peripheral blood of AR patients. The expression of NGF, BDNF and NT-3 mRNA have been tested by real-time quantitative RT-PCR.Comparing with the healthy adults, the expression of NGF, BDNF and NT-3 mRNA as 2(-deltadeltaCt) are 2.436 8, 4.4588 and 1.781 8 respectively. The increasing expression of NT-3 correlated positively with the scores of visual analog scale.The expression of NGF, BDNF and NT-3 mRNA are as high as 2.4368, 4.4588 and 1.7818 times to healthy adults. We propose NGF, BDNF and NT-3 may contribute to the pathogenesis of AR. NT-3 could reflect the severity of rhinitis as a molecular biological index.

Methyl glycopyranoside derivatives react with arylaldehyde dimethyl acetals such as (II) in the presence of a squaramide type catalyst to afford 4,6-O-arylidene carbohydrates in good yields.

are accessible to activation with catalyticamounts of an acid, they are ideally suited for such studies.Obviously, it is hoped that not only the reaction rate and theproduct yield but also the anomeric selectivity will begoverned by the interaction of a thiourea cocatalyst withthe substrates (glycosyl donor and acceptor) and the catalyst.As compound 4 has proven to be very successful in previousthiourea-based studies

Several C-(alpha-D-glucopyranosyl)-phenyldiazomethanes, with different substituent groups at the paraposition of the phenyl ring, were prepared. The stabilities of these diazo compounds were investigated through NMR and UV monitoring. The para-cyano substituted diazo compound was found to be stable in neutral media (pH 7.0 buffer) and could be isolated. Inhibitory activity investigations indicated that this compound is an irreversible inhibitor against a-glucosidase from Saccharomyces cerevisiae.

are accessible to activation with catalyticamounts of an acid, they are ideally suited for such studies.Obviously, it is hoped that not only the reaction rate and theproduct yield but also the anomeric selectivity will begoverned by the interaction of a thiourea cocatalyst withthe substrates (glycosyl donor and acceptor) and the catalyst.As compound 4 has proven to be very successful in previousthiourea-based studies

To investigate the effect of NF-κB inhibitor PDTC on inflammation response in mice with herpetic stromal keratitis (HSK).A total of 120 female BALB/c mice, aged 4~6 weeks, were treated by scuffing the epithelium of the right cornea with the tip of a 30G syringe needle, and approximately 1 ×106PFU of HSV-1virus was seeded onto the corneal surface. The eye was then exposed to 170mJ/cm2 of UV light 7 weeks later, in order to induce the relapse of HSK. PDTC eye drops were adjusted to various concentrations (0.1, 1.0, and 10 mg/ml) with PBS; PBS only was used on control animals. All animals received PDTC or PBS eye drops 6 times/day, 1 drop/time, for 7 consecutive days. Mice were sacrificed at 8h, and 1, 3, and 7 d after administration. Corneal tissues were prepared for the detection of IL-1β, IL-4, IL-6, and IL-12 by ELISA and histological study.Neutrophilic leukocytes and lymphocytes were found in the corneas of HSK mice. ELISA results showed fluctuating expressions of IL-1β, IL-4, IL-6, and IL-12. The IL-1β and IL-4 expressions were significantly lower in the high dose group than in the control group (P0.05), while IL-6 and IL-12 expressions were significantly higher in the high dose group than in the control group (P0.05).A high concentration of PDTC can suppress the expression of certain inflammatory factors in HSK mice while improving the expression of others.

It is found that the carbohydrates can undergo highly α-selective glycosylations in the presence of BF3 or SnCl4.

To investigate the effect of autologous peripheral nerve grafting on retinal ganglion cell survival and axonal regeneration after an injury, the optic nerve of adult Sprague-Dawley rats was transected and grafted with an autologous peripheral nerve from the peroneal branch of the left sciatic nerve. The numbers of both surviving and axon-regenerating retinal ganglion cells were determined at different times after surgery. The majority of retinal ganglion cells were rapidly lost within 3 weeks, followed by a slow and protracted phase of cell loss until the end of the 6-month study. FluoroGold-labelled axon-regenerating retinal ganglion cells were first detected by 2 weeks, followed by a period of high axonal regeneration that peaked at 8 weeks and accounted for over 35% of the total surviving retinal ganglion cells. However, retinal ganglion cells with regenerated axons eventually died. Our data thus indicate that axonal regeneration in the autologous peripheral nerve graft is insufficient to sustain the long-term survival of axotomized retinal ganglion cells.

Catalytic or stoichiometric amounts of Lewis acids were found to be very effective α-directing additives in the stereoselective glycosylations of diverse 2,3-O-carbonate-protected glucose and galactose thioglycoside donors by preactivation protocol. The poor stereoselectivities of 4,6-di-O-acetyl-2,3-O-carbonate protected thioglycoside donors in glycosyl coupling reactions were greatly improved, and excellent α-stereoselectivities were achieved by the addition of 0.2 equiv of BF(3)·OEt(2). On the other hand, the β-selectivities of 4,6-di-O-benzyl-2,3-O-carbonate-protected thioglucoside donor toward glycosylations were reversed completely to the α-selectivities by the use of 1 equiv of SnCl(4), making the stereoselectivity controllable. Furthermore, the poor stereoselectivities of 4,6-di-O-benzyl-2,3-O-carbonate-protected thiogalactoside donor in glycosylations were also improved by using SnCl(4) as additive.