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1.
J Am Chem Soc ; 146(11): 7616-7627, 2024 Mar 20.
Article in English | MEDLINE | ID: mdl-38446772

ABSTRACT

Natural products and their analogues are significant sources of therapeutic lead compounds. However, synthetic strategies for generating large collections of these molecules remain a significant challenge. The most difficult step in their synthesis is the design of a common intermediate that can be easily transformed into natural products belonging to different families. This study demonstrates the evolution of synthetic tactics designed to assemble the functionalized piperidines present in indole alkaloids from a common intermediate. More importantly, we also report a previously unknown Ir- and Er-catalyzed dehydrogenative spirocyclization reaction that enables direct access to spirocyclic oxindole alkaloids. As a practical application, the asymmetric total syntheses of 29 natural alkaloids belonging to different families were accomplished by following a uniform synthetic route. The proposed methodology extends the capability of the iridium-catalyzed dehydrogenative coupling reaction to the realm of indole-alkaloid synthesis and provides new opportunities for the efficient preparation of natural product-like molecules.


Subject(s)
Alkaloids , Biological Products , Humans , Stereoisomerism , Indole Alkaloids , Oxindoles
2.
Scand J Gastroenterol ; 57(12): 1503-1508, 2022 12.
Article in English | MEDLINE | ID: mdl-35758188

ABSTRACT

BACKGROUND: The selection of endoscopic treatments for small rectal neuroendocrine tumors is controversial. OBJECTIVE: To retrospectively compare the effectiveness and safety of precut endoscopic mucosal resection (EMR-P) and endoscopic submucosal dissection (ESD) for small rectal neuroendocrine tumors (NETs). METHODS: Data from 98 patients with small rectal NETs who were hospitalized at Shenzhen Second People's Hospital between August 2014 and November 2021 were collected. The en bloc resection rate, pathological complete resection rate, radical resection rate, operation time, adverse event rate and hospital stay were compared between the two groups. RESULTS: The operation time in the EMR-P group was significantly shorter than that in the ESD group. The median hospital stay in the EMR-P group was also significantly shorter than that in the ESD group. There were no significant differences between the two groups in terms of the en bloc resection, complete resection or radical resection rates. There was also no significant difference in the incidence of adverse events between the two groups. The delayed bleeding and delayed perforation rates of the two groups were improved after conservative treatment without surgery. There was no significant difference in the rate of positive vertical margins and horizontal margins between the EMR-P group and the ESD group. No local recurrence or metastasis was found during follow-up. CONCLUSION: EMR-P is an effective and safe endoscopic treatment for rectal NETs with a diameter of less than 10 mm. EMR-P is a significantly shorter procedure and requires a shorter hospital stay than ESD. EMR-P does not increase the cut margin positivity rate.


Subject(s)
Endoscopic Mucosal Resection , Neuroendocrine Tumors , Rectal Neoplasms , Humans , Endoscopic Mucosal Resection/adverse effects , Endoscopic Mucosal Resection/methods , Neuroendocrine Tumors/surgery , Neuroendocrine Tumors/pathology , Retrospective Studies , Treatment Outcome , Rectal Neoplasms/surgery , Rectal Neoplasms/pathology , Margins of Excision , Intestinal Mucosa/pathology , Neoplasm Recurrence, Local/epidemiology
3.
Gut Pathog ; 14(1): 20, 2022 May 26.
Article in English | MEDLINE | ID: mdl-35619175

ABSTRACT

BACKGROUND: Intestinal microbiota transplantation (IMT) has been recognized as an effective treatment for recurrent Clostridium difficile infection (rCDI) and a novel treatment option for other diseases. However, the safety of IMT in patients has not been established. AIMS: This systematic review and meta-analysis was conducted to assess the safety of IMT. METHODS: We systematically reviewed all randomized controlled trials (RCTs) of IMT studies published up to 28 February 2021 using databases including PubMed, EMBASE and the Cochrane Library. Studies were excluded if they did not report adverse events (AEs). Two authors independently extracted the data. The relative risk (RR) of serious adverse events (SAEs) and common adverse events (CAEs) were estimated separately, as were predefined subgroups. Publication bias was evaluated by a funnel plot and Egger's regression test. RESULTS: Among 978 reports, 99 full-text articles were screened, and 20 articles were included for meta-analysis, involving 1132 patients (603 in the IMT group and 529 in the control group). We found no significant difference in the incidence of SAEs between the IMT group and the control group (RR = 1.36, 95% CI 0.56-3.31, P = 0.50). Of these 20 studies, 7 described the number of patients with CAEs, involving 360 patients (195 in the IMT group and 166 in the control group). An analysis of the eight studies revealed that the incidence of CAEs was also not significantly increased in the IMT group compared with the control group (RR = 1.06, 95% CI 0.91-1.23, P = 0.43). Subgroup analysis showed that the incidence of CAEs was significantly different between subgroups of delivery methods (P(CAE) = 0.04), and the incidence of IMT-related SAEs and CAEs was not significantly different in the other predefined subgroups. CONCLUSION: Currently, IMT is widely used in many diseases, but its associated AEs should not be ignored. To improve the safety of IMT, patients' conditions should be fully evaluated before IMT, appropriate transplantation methods should be selected, each operative step of faecal bacteria transplantation should be strictly controlled, AE management mechanisms should be improved, and a close follow-up system should be established.

4.
J Org Chem ; 86(18): 12762-12771, 2021 09 17.
Article in English | MEDLINE | ID: mdl-34464147

ABSTRACT

A one-step synthesis of diversely substituted pyrazolo[1,5-a]pyrimidines from saturated ketones and 3-aminopyrazoles is presented. This transformation involves the in situ formation of α,ß-unsaturated ketones via a radical process, followed by [3+3] annulation with 3-aminopyrazoles in one pot. Mechanistic studies have shown that the dual C(sp3)-H bond functionalization of inactive ketones is required for the formation of the title compounds. Notably, this dehydrogenative coupling process provides access to a host of functionalized pyrazolo[1,5-a]pyrimidines with antitumor potential from commercially available substrates.


Subject(s)
Ketones , Pyrimidines , Catalysis , Molecular Structure , Physical Phenomena
5.
J Comp Physiol B ; 191(4): 755-764, 2021 07.
Article in English | MEDLINE | ID: mdl-34091751

ABSTRACT

Individual variations in metabolic rate, locomotion capacity and hypoxia tolerance and their relationships were investigated in three cyprinid species [crucian carp (Carassius auratus), common carp (Cyprinus carpio) and qingbo (Spinibarbus sinensis), in 60 individuals of each species]. Either the active metabolic rate (AMR) and critical swimming speed (Ucrit) (30 individuals) or critical oxygen tension (Pcrit) and loss of equilibrium (LOE) (30 individuals) were measured in each species after measuring the resting metabolic rate (RMR). Both the AMR and Ucrit were found to be significantly and positively correlated with the RMR in all three cyprinid species, indicating that high-RMR individuals have high aerobic capacity and thus good swimming performance. Pcrit was positively correlated with the RMR in all three species, whereas the LOE was highly positively correlated, weakly positively correlated and not correlated with the RMR in qingbo, common carp and crucian carp, respectively, possibly due to specialized morphological and biochemical adaptations involved in hypoxia tolerance in crucian and common carp. Crucian carp showed relatively poor swimming performance, i.e., a low Ucrit (relatively high variation), strong hypoxia tolerance, and low LOE (relatively low variation); qingbo showed relatively good swimming performance (relatively low variation) and weak hypoxia tolerance (relatively high variation); and common carp showed moderate swimming performance and relatively strong hypoxia tolerance (moderate variation). These interspecific differences may be due to the different lifestyles of these cyprinid fishes based on their associated fast-slow-flow regime and are outcomes of long-term selection.


Subject(s)
Carps , Animals , Fresh Water , Goldfish , Humans , Hypoxia , Locomotion
6.
Dis Aquat Organ ; 143: 195-203, 2021 Feb 25.
Article in English | MEDLINE | ID: mdl-33629662

ABSTRACT

Cyprinid herpesvirus 2 (CyHV-2) has become a serious threat to the gibel carp Carassius auratus gibelio industry and has led to enormous losses worldwide. We have therefore developed an immunochromatographic strip (ICS) to enable rapid on-site detection of CyHV-2 by aquaculture facility staff. The ICS employs 2 monoclonal antibodies (MAbs 2C3-1E6 and 3H2-1G5) against the ORF25 protein, a CyHV-2 membrane protein, as the capture and detection antibodies, respectively. Indirect immunofluorescence assay (IIFA) and Western blotting of CyHV-2-infected fathead minnow cells indicated that the 2 MAbs could specifically bind CyHV-2 by recognizing ORF25 antigen. Sandwich ELISA showed that the detection limit of ORF25 protein halved when MAb 2C3-1E6 served as the capture antibody compared to MAb 3H2-1G5. The test for detecting purified CyHV-2 using the ICS could be completed in 10 min and the sensitivity was 1 µg ml-1. Sensitivity of the ICS remained stable following storage at 4, 25 and 37°C for 6 mo. Tissue homogenate from gibel carp with and without obvious gill hemorrhages was subjected to CyHV-2 detection using the ICS: the results were in good accordance with conventional PCR. Our ICS does not require highly trained technicians or specialized equipment, making it suitable for rapid diagnosis of CyHV-2 infection both in the laboratory and in the field.


Subject(s)
Cyprinidae , Fish Diseases , Herpesviridae Infections , Herpesviridae , Animals , Fish Diseases/diagnosis , Herpesviridae Infections/diagnosis , Herpesviridae Infections/veterinary
7.
JGH Open ; 4(4): 707-712, 2020 Aug.
Article in English | MEDLINE | ID: mdl-32782960

ABSTRACT

BACKGROUND AND AIM: While adenoma detection rate (ADR) is an important quality metric for screening colonoscopy, it remains difficult to be accessed due to the lack of integrated endoscopy and pathology databases. Hence, the use of an adenoma-to-polyp detection rate quotient and polyp detection rate (PDR) has been proposed to predict ADR. This study aimed to examine the usefulness of estimated ADR across different colonic segments in two age groups for Shenzhen people in China. METHODS: We retrospectively analyzed 7329 colonoscopy procedures performed by 12 endoscopists between January 2012 and February 2014. The PDR, actual ADR, and estimated ADR of the entire, proximal, and distal colon, and within each colonic segment, in two patient age groups: <50 and ≥50 years, were calculated for each endoscopist. RESULTS: The overall polyp and adenoma prevalence rates were 19.1 and 9.3%, respectively. The average age of adenoma-positive patients was significantly higher than that of adenoma-negative patients (54 ± 12.6 years vs 42.9 ± 13.2 years, respectively). A total of 1739 polyps were removed, among which 826 were adenomas. More adenomatous polyps were found in the proximal colon (60.4%, 341/565) than in the distal colon (40.9%, 472/1154). Overall, both actual and estimated ADR correlated strongly at the entire colon level and within most colonic segments, except for the cecum and rectum. In both age groups, these parameters correlated strongly within the traverse colon and descending colon. CONCLUSION: Caution should be exercised when predicting ADR within the sigmoid colon and rectum.

8.
Can J Gastroenterol Hepatol ; 2017: 7615736, 2017.
Article in English | MEDLINE | ID: mdl-28808653

ABSTRACT

BACKGROUND AND AIMS: Acyl-CoA synthetase 5 (ACS5) has been reported to be associated with the development of various cancers, but the role of it in colorectal cancer (CRC) is not well understood. The present study aimed to explore the potential role of ACS5 in the development and progression of CRC. METHODS: ACS5 expression in CRC tissues and CRC cell lines was examined, and its clinical significance was analyzed. The role of ACS5 in cell proliferation, apoptosis, and invasion was examined in vitro. RESULTS: We found that ACS5 expression was upregulated in CRC cells and CRC tissues and that high ACS5 expression was more frequent in CRC patients with excess muscular layer and with poor tumor differentiation. Furthermore, knockdown of ACS5 in HT29 and SW480 cells significantly dampened cell proliferation, induced cell apoptosis, and reduced cell migration and invasion. In contrast, the ectopic overexpression of ACS5 in LOVO and SW620 cells remarkably promoted cell proliferation, inhibited cell apoptosis, and enhanced cell migration and invasion. Enhanced cell growth and invasion ability mediated by the gain of ACS5 expression were associated with downregulation of caspase-3 and E-cadherin and upregulation of survivin and CD44. CONCLUSIONS: Our data demonstrate that ACS5 can promote the growth and invasion of CRC cells and provide a potential target for CRC gene therapy.


Subject(s)
Cell Proliferation/genetics , Coenzyme A Ligases/metabolism , Colorectal Neoplasms/pathology , Neoplasm Invasiveness/genetics , Cadherins/genetics , Caspase 3/genetics , Cell Line, Tumor , Cell Movement/genetics , Disease Progression , Down-Regulation , Gene Expression Regulation, Neoplastic , Gene Knockdown Techniques , HT29 Cells , Humans , Hyaluronan Receptors/genetics , Inhibitor of Apoptosis Proteins/genetics , Survivin , Up-Regulation
9.
Front Pharmacol ; 8: 324, 2017.
Article in English | MEDLINE | ID: mdl-28620304

ABSTRACT

Background and Objective: Tea drinking is associated with positive effects on bone health and may protect against osteoporosis, especially in elderly women. Pu-erh tea has many beneficial effects on human health; however, whether Pu-erh tea has anti-osteoporotic potential remains unclear. Thus, we investigated the effects of Pu-erh tea extract (PTE) on ovariectomy-induced osteoporosis in rats and on osteoclastogenesis in vitro. Methods: Female Wistar rats were divided into six groups: the sham, model, and Xian-Ling-Gu-Bao capsule (XLGB) groups, and the low-, medium-, and high-dose PTE groups. Ovariectomized (OVX) rats were used as an animal model of osteoporosis. The animals were intragastrically administered distilled water, XLGB, or different concentrations of PTE for 13 weeks. Body weight, blood biochemical indicators, relative organ coefficients, femoral bone mineral density (BMD), bone biomechanical properties, and bone microarchitecture were examined and analyzed. Additionally, the in vitro effects of PTE on osteoclastic activities were investigated using the RAW 264.7 cell line as an osteoclast differentiation model. The effects of PTE on osteoclast differentiation and the expression of osteoclast-specific genes and proteins were determined. Results: PTE reduced OVX-induced body weight gain after 6 weeks of treatment, and the high-dose exerted a significant effect. High-dose PTE significantly ameliorated OVX-induced estradiol (E2) deficiency. PTE treatment maintained calcium and phosphorus homeostasis and improved other blood biochemical parameters to various degrees. In addition, PTE treatment improved organ coefficients of the femur, uterus, and vagina and improved femoral BMD and bone biomechanical properties. PTE treatment strikingly ameliorated bone microarchitecture. Moreover, in the in vitro studies, osteoclast differentiation using the differentiation cell model was significantly inhibited by PTE without cytotoxic effects. Additionally, PTE efficaciously suppressed the expression of key osteoclast-specific genes and proteins. Conclusion: PTE can ameliorate ovariectomy-induced osteoporosis in rats and suppress osteoclastogenesis in vitro.

10.
Ecotoxicol Environ Saf ; 134P1: 179-185, 2016 Dec.
Article in English | MEDLINE | ID: mdl-27619353

ABSTRACT

Endosulfan is a chlorinated and genotoxic insecticide extensively used worldwide in agriculture. However, residues of endosulfan can be detected in farmland soil and natural water. In this study, toxic effects of endosulfan were studied by measuring micronuclei and dyskaryosis in peripheral erythrocytes of topmouth gudgeon (Pseudorasbora parva). In addition, liver antioxidant enzyme activity and lipid peroxidation level were measured. P. parva were exposed to control and 5 doses (0.12, 0.16, 0.21, 0.31 and 0.62µg/L) of endosulfan for 48h and 96h. The frequencies of micronuclei and dyskaryosis, antioxidant enzyme activity, contents of ROS and lipid peroxidation increased by endosulfan exposure. Compared to controls, frequencies of micronuclei and dyskaryosis were significantly increased with endosulfan exposure, and an obvious dose-response relationship was found. Endosulfan has potential genotoxicity by inducing the oxidative stress and lipid peroxidation, which probably lead to the occurrence of micronuclei and dyskaryosis in erythrocytes.

11.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 45(3): 529-32, 2014 May.
Article in Chinese | MEDLINE | ID: mdl-24941833

ABSTRACT

OBJECTIVE: To analyze the efficacy and safety of subcutaneous administration of bortezomib in the treatment of multiple myeloma (MM) patients. METHODS: A total of 26 MM patients were enrolled in this study and treated with BDT (bortezomib-dexamethasone-thalidomide). In the 26 MM patients, 12 patients received subcutaneous administration of Bortezomib while 14 patients received conventional intravenous administration. The outcomes and adverse effects of two groups were retrospectively evaluated and compared. RESULTS: Overall response (OR) rates in the two groups were 75.00% and 71.43% respectively, in which complete remission (CR) plus very good complete remission (VGPR) rates were 50.00% and 47.14%, while CR rates were 16.67% and 28.57%. There were no statistically significant difference (P > 0.05). Time to achieve effectiveness in two groups was similar (P > 0.05). More than half patients in both groups achieved partial remission after the first treatment course and CR after the fourth course. Compared to the intravenous group, peripheral neuropathy rates remained significantly lower in subcutaneous group (16.67% vs. 64.29%, P = 0.021). The intravenous group had 7.14% grade 3 or worse, peripheral neuropathy but none found in the subcutaneous group. Rash occurred only in subcutaneous group (66.67%), but it was local, mild and transitional. No significant differences of other adverse events between the two groups were observed. CONCLUSION: Subcutaneous administration of bortezomib offers similar efficacy to standard intravenous administration in the treatment of multiple myelom, with an improved safety for lower rate of peripheral neuropathy.


Subject(s)
Boronic Acids/administration & dosage , Multiple Myeloma/drug therapy , Pyrazines/administration & dosage , Remission Induction , Antineoplastic Combined Chemotherapy Protocols , Boronic Acids/therapeutic use , Bortezomib , Dexamethasone , Humans , Infusions, Intravenous , Injections, Subcutaneous , Pyrazines/therapeutic use , Retrospective Studies
12.
World J Gastroenterol ; 15(17): 2151-5, 2009 May 07.
Article in English | MEDLINE | ID: mdl-19418589

ABSTRACT

AIM: To systematically assess the efficacy and safety of beta-adrenergic blocker plus 5-isosorbide mononitrate (BB + ISMN) and endoscopic band ligation (EBL) on prophylaxis of esophageal variceal rebleeding. METHODS: Randomized controlled trials (RCTs) comparing the efficacy and safety of BB + ISMN and EBL on prophylaxis of esophageal variceal rebleeding were gathered from Medline, Embase, Cochrane Controlled Trial Registry and China Biological Medicine database between January 1980 and August 2007. Data from five trials were extracted and pooled. The analyses of the available data using the Revman 4.2 software were based on the intention-to-treat principle. RESULTS: Four RCTs met the inclusion criteria. In comparison with BB + ISMN with EBL in prophylaxis of esophageal variceal rebleeding, there was no significant difference in the rate of rebleeding [relative risk (RR), 0.79; 95% CI: 0.62-1.00; P = 0.05], bleeding-related mortality (RR, 0.76; 95% CI: 0.31-1.42; P = 0.40), overall mortality (RR, 0.81; 95% CI: 0.61-1.08; P = 0.15) and complications (RR, 1.26; 95% CI: 0.93-1.70; P = 0.13). CONCLUSION: In the prevention of esophageal variceal rebleeding, BB + ISMN are as effective as EBL. There are few complications with the two treatment modalities. Both BB + ISMN and EBL would be considered as the first-line therapy in the prevention of esophageal variceal rebleeding.


Subject(s)
Adrenergic beta-Antagonists/therapeutic use , Endoscopy , Esophageal and Gastric Varices/prevention & control , Isosorbide Dinitrate/analogs & derivatives , Ligation , Vasodilator Agents/therapeutic use , Esophageal and Gastric Varices/etiology , Esophageal and Gastric Varices/therapy , Humans , Isosorbide Dinitrate/therapeutic use , Liver Cirrhosis/complications , Randomized Controlled Trials as Topic , Treatment Outcome
14.
Biotechnol Lett ; 28(12): 869-75, 2006 Jun.
Article in English | MEDLINE | ID: mdl-16786271

ABSTRACT

The glycinin G1 gene encodes a soybean seed storage protein accumulating at a high level. We have used the G1 promoter to confer seed-specific expression of human basic fibroblast growth factor (bFGF) in transgenic soybeans. The coding region of 18 kDa bFGF was fused to the promoter or promoter-signal peptide sequence of G1 gene, and transferred into soybean. Analysis of transgenic plants demonstrated that bFGF transcript or protein was confined to the seeds. The highest level of bFGF accumulation in the seeds reached up to 2.3% of total soluble protein. The soybean-derived bFGF was biologically active as confirmed by its mitogenic activity on Balb/c 3T3 cells, and exhibited other properties identical to native bFGF. We also observed a seed-specific expression of beta-glucuronidase driven by the G1 promoter. These results indicated that the G1 promoter contains essential cis-elements for seed-specific expression, and thus can be used for expression of pharmaceutical proteins in soybean seeds.


Subject(s)
Fibroblast Growth Factor 2/metabolism , Glycine max/genetics , Mitogens/biosynthesis , Plants, Genetically Modified/metabolism , Seeds/metabolism , Animals , BALB 3T3 Cells , Fibroblast Growth Factor 2/genetics , Fibroblast Growth Factor 2/pharmacology , Gene Expression Regulation, Plant/genetics , Globulins/genetics , Humans , Mice , Promoter Regions, Genetic , Seeds/genetics , Soybean Proteins/genetics
15.
Biochim Biophys Acta ; 1594(1): 100-8, 2002 Jan 31.
Article in English | MEDLINE | ID: mdl-11825612

ABSTRACT

Alkaline phosphatase from Megalobatrachus japonicus was inactivated by diethyl pyrocarbonate (DEP). The inactivation followed pseudo-first-order kinetics with a second-order rate constant of 176 M(-1) x min(-1) at pH 6.2 and 25 degrees C. The loss of enzyme activity was accompanied with an increase in absorbance at 242 nm and the inactivated enzyme was re-activated by hydroxylamine, indicating the modification of histidine residues. This conclusion was also confirmed by the pH profiles of inactivation, which showed the involvement of a residue with pK(a) of 6.6. The presence of glycerol 3-phosphate, AMP and phosphate protected the enzyme against inactivation. The results revealed that the histidine residues modified by DEP were located at the active site. Spectrophotometric quantification of modified residues showed that modification of two histidine residues per active site led to complete inactivation, but kinetic stoichiometry indicated that one molecule of modifier reacted with one active site during inactivation, probably suggesting that two essential histidine residues per active site are necessary for complete activity whereas modification of a single histidine residue per active site is enough to result in inactivation.


Subject(s)
Alkaline Phosphatase/chemistry , Amphibians/metabolism , Histidine/analysis , Alkaline Phosphatase/antagonists & inhibitors , Animals , Binding Sites , Diethyl Pyrocarbonate/pharmacology , Hydrogen-Ion Concentration , Spectrophotometry, Ultraviolet , Substrate Specificity
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