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1.
Zhonghua Shao Shang Za Zhi ; 37(5): 453-459, 2021 May 20.
Article in Chinese | MEDLINE | ID: mdl-34044527

ABSTRACT

Objective: To explore the clinical effects of anterolateral thigh perforator flap with sensory nerves in repairing the plantar skin and soft tissue defects. Methods: From January 2016 to March 2019, 13 male patients with plantar skin and soft tissue defects were admitted to the Department of Foot and Ankle Surgery of Ruihua Affiliated Hospital of Soochow University, aged 27 to 73 years. The retrospective cohort study was conducted. The wounds of 4 patients underwent 2 times of debridement. The wounds of 9 patients underwent 1 time of debridement and 1 or 2 time(s) of vacuum sealing drainage. Then all the wounds of patients were repaired with flaps when the wounds were clean and dry with no purulent exudation and were negative in secretion culture. The wound areas of this group of patients after wound debridement were 13.0 cm×5.5 cm to 36.0 cm×10.5 cm, and the wounds were repaired with anterolateral thigh perforator flaps with sensory nerves with area of 14 cm×6 cm to 37 cm×11 cm. The wound of 1 patient was repaired with a bilobed flap. The oblique or descending branch of the lateral circumflex femoral artery and its accompanying vein in the flap were anastomosed with the posterior tibial artery and its accompanying vein or the medial plantar artery and its accompanying vein in recipient sites. The lateral femoral cutaneous nerve in the flap was anastomosed with the recipient saphenous nerve or medial plantar cutaneous nerve. The donor sites were directly sutured. The survival of flaps and the healing of wounds in the donor and recipient areas were recorded, and the ulcers of the plantar repaired flap were followed up for 3 months after operation. The sensory function of the flap was evaluated by the sensory evaluation standard of British Medical Research Council (BMRC), and the ankle and foot function score system of American Orthopedic Foot and Ankle Society (AOFAS) was used for comprehensive functional evaluation at the last follow-up. Results: All the 14 flaps in 13 cases survived, and venous crisis occurred in two cases and the flaps survived smoothly after the venous re-anastomosis. One patient developed deep tissue infection after being discharged and was healed after secondary debridement. The donor and recipient areas of the remaining patients healed well. The patients were followed up for 6 to 18 months, the shape of flaps was slightly bloated in 5 patients, and the shape and texture of flaps in the other 8 patients were good. Six patients had ulcers in flaps at 3 months of follow-up after operation, which were healed after stopping weight-bearing activities. At the last follow-up, little linear scar hyperplasia could be seen in the donor site of patients; the BMRC sensory function evaluation results were S1 grade in 4 cases, S2 grade in 7 cases, and S3 grade in 2 cases; the AOFAS scores were excellent in 3 cases, good in 7 cases, fair in 2 cases, and poor in 1 case. Conclusions: The anterolateral thigh perforator flaps with sensory nerves can repair the plantar skin and soft tissue defects with the donor sites directly sutured and good shape of flaps, which provide a good treatment method for the recovery of plantar proprioceptive sensation and weight-bearing function.


Subject(s)
Perforator Flap , Plastic Surgery Procedures , Soft Tissue Injuries , Humans , Male , Retrospective Studies , Skin Transplantation , Soft Tissue Injuries/surgery , Thigh/surgery , Treatment Outcome
2.
Zhonghua Yan Ke Za Zhi ; 55(9): 658-664, 2019 Sep 11.
Article in Chinese | MEDLINE | ID: mdl-31495150

ABSTRACT

Objective: To evaluate the clinical effect of three-dimensional printing combined with surgical navigation and endoscopy for orbital fracture reconstruction. Methods: A case series study. Twenty-eight patients (28 eyes) with orbital fractures (20 males and 8 females, aged 10-61 years, with simple orbital fractures in 22 patients and composite orbital fractures in 6 patients) were treated with three-dimensional printing combined with surgical navigation and endoscopy for orbital fracture reconstruction at Affiliated Eye Hospital of Nanchang University from July 2016 to June 2018. With the help of three-dimensional printed models and guides, navigation positioning guidance and endoscopic visualization performance, the soft tissue incarcerated in the orbital fracture area was loosened, and the repair material was implanted (video attached). Postoperative follow-up was conducted at 1 week and 3 months. The follow-up observation included the best corrected visual acuity, diplopia, dyskinesia of the eyes, enophthalmos, and orbital volume. The data were analyzed by the paired t-test, Wilcoxon and the Mann-Whitney U rank sum test. Results: The best corrected visual acuity before and 1 week after surgery was 4.714±0.400 and 4.732±0.377, respectively, and the difference was not statistically significant (t=1.724, P=0.096). The enophthalmos before and 1 week after surgery was 2.2 (2.0-5.0) mm and 0.3 (0.0-2.3) mm, respectively, and the difference was significant (Z=-4.604, P<0.01). The orbital volume before and 1 week after surgery was 2 008.10 (6.84-11 200.00) mm(3) and 478.76 (5.01-7 286.00) mm(3), respectively, and the difference was statistically significant (Z=-3.735, P<0.01).The preoperative diplopia degree was 0, Ⅰ, Ⅱ, and Ⅲ in 14, 11, 3, and 0 eyes, while the degree of diplopia 3 months after surgery was 0, Ⅰ, Ⅱ, and Ⅲ in 22, 6, 0, and 0 eyes, respectively. The difference was statistically significant (Z=-2.359, P=0.018). The preoperative dyskinesia degree of the eyes was 0, Ⅰ, Ⅱ, and Ⅲ in 11, 11, 3, and 3 eyes, while the dyskinesia degree of the eyes 3 months after surgery was 0, Ⅰ, Ⅱ, and Ⅲ in 23, 5, 0, and 0 eyes, respectively. The difference was statistically significant (Z=-3.456, P=0.001). No implant infection, displacement, and other serious complications were observed during the follow-up of 3 to 12 months. Conclusions: Three-dimensional printing technology combined with nasal endoscopy and surgical navigation, which is applied in the reconstruction of orbital fracture, can significantly improve the symptoms of diplopia, ocular dyskinesia, and ocular depression. It is a feasible assistant method. (Chin J Ophthalmol, 2019, 55: 658-664).


Subject(s)
Enophthalmos , Orbital Fractures , Plastic Surgery Procedures , Printing, Three-Dimensional , Adolescent , Adult , Child , Endoscopy , Female , Humans , Male , Middle Aged , Orbit , Orbital Fractures/surgery , Tomography, X-Ray Computed , Young Adult
3.
J Phys Condens Matter ; 27(22): 225501, 2015 Jun 10.
Article in English | MEDLINE | ID: mdl-25985389

ABSTRACT

We report investigation of the structural phase transition and electronic properties of Hf(1-x)N (0 ⩽ x ⩽ 0.25) using first principles calculations. The defective NaCl-type structure with Hf vacancies (V(Hf)) is found to be stable over a large phase region. Hf3N4 with the Zr3N4-type structure is only stable in relative small region and readily destabilized when the stoichiometric ratio of N to Hf deviates from 4/3. The electronic and optic properties of Hf(1-x)N are controlled by the concentration of V(Hf). The full depletion of excess free electrons from Hf atoms results in the structural phase transition of Hf3N4.

4.
Article in English | MEDLINE | ID: mdl-23915026

ABSTRACT

Ovalbumin (OVA), one of the major allergens in hen egg white, and has widespread use in experimental models of allergy. The aim of this research was to assess the effect of glycation and heat treatment on the potential allergenicity of OVA prepared from hen egg white. Secondary and tertiary structures of OVA were also characterised to show the relationship between potential allergenicity and the conformation of OVA after heating and glycation. Glycation significantly reduced the potential allergenicity of OVA tested with egg allergy patients' sera, which was caused by conformation changes. An increased IgG reactivity was measured using rabbit anti-OVA and was supposed to be caused by protein unfolding which exposed hidden epitopes. Heating reduced the potential allergenicity of OVA at the expense of increased IgG reactivity. It is suggested that conformational changes of OVA induced by glycation and controlled heating significantly reduced its potential allergenicity.


Subject(s)
Allergens/chemistry , Allergens/immunology , Avian Proteins/chemistry , Avian Proteins/immunology , Ovalbumin/chemistry , Ovalbumin/immunology , Allergens/adverse effects , Animals , Antibody Specificity , Avian Proteins/adverse effects , Chickens , Egg Hypersensitivity/immunology , Glycosylation , Hot Temperature , Humans , Immunoglobulin E/blood , Ovalbumin/adverse effects , Protein Conformation , Protein Structure, Secondary , Protein Structure, Tertiary , Rabbits
5.
Lett Appl Microbiol ; 45(1): 62-7, 2007 Jul.
Article in English | MEDLINE | ID: mdl-17594462

ABSTRACT

AIMS: To rapidly determine the causative agent of mass death in Lateolabrax japonicus in Zhelin Bay of Guangdong Province in China in April 2004. METHODS AND RESULTS: Thirty-six strains, numbered sequentially from RP01 to RP36, were isolated from six diseased fish. All of the strains were identified as being of the same vibrio species according to the results of universal primer PCR combined with DGGE (UPPCR-DGGE). RP30 was one of these strains that was randomly selected and analysed by using a morphological, physiological and biochemical plate, Biolog GN2 Microplate System and API 20E system. Furthermore, RP30' 16S rDNA was sequenced and aligned in Genbank. Its virulence to Lateolabrax japonicus (Cuvier in Cuvier and Valenciennes) was also tested. RP30 is most closely related to four Vibrio ponticus strains (99.3% similarity). LD50s were 2.5 (x103 CFU per fish for intraperitoneal inoculation (IP) and 3.2 (x103 CFU per fish for intramuscular inoculation (IM), respectively. CONCLUSIONS: The investigated pathogenic agent of Lateolabrax japonicus (Cuvier in Cuvier and Valenciennes) was V. ponticus. SIGNIFICANCE AND IMPACT OF THE STUDY: UPPCR-DGGE is very helpful in epidemiologic investigation. Interestingly, this is the first report that V. ponticus infects cultured marine fish. DGGE was likewise first introduced to epidemiologic investigation of fish disease.


Subject(s)
Aquaculture , Bass/microbiology , Fish Diseases/physiopathology , Vibrio Infections/veterinary , Vibrio/classification , Vibrio/pathogenicity , Animals , Bacterial Typing Techniques , Electrophoresis, Polyacrylamide Gel/methods , Fish Diseases/microbiology , Molecular Sequence Data , Polymerase Chain Reaction , Sequence Analysis, DNA , Vibrio/genetics , Vibrio/isolation & purification , Vibrio Infections/microbiology , Vibrio Infections/physiopathology , Virulence
6.
Lett Appl Microbiol ; 41(2): 202-7, 2005.
Article in English | MEDLINE | ID: mdl-16033522

ABSTRACT

AIMS: To investigate the distribution of the virulence of two Vibrio species among different strains obtained from the mariculture systems on the coast of Guangdong in China and the correlation between the virulence strains and the virulence genes among Vibrio alginolyticus. METHODS: Besides three strains, 72 V. alginolyticus strains and seven Vibrio parahaemolyticus strains were examined by PCR or semi-nested PCR for the virulence genes (tlh, trh, tdh, toxR, toxRS, ctxA, VPI). Additionally, the virulence of 18 V. alginolyticus strains was tested. SIGNIFICANCE AND IMPACT OF THE STUDY: Virulence genes homologous to those in the V. parahaemolyticus and Vibrio cholerae are widely distributed among V. alginolyticus and V. parahaemolyticus in the coastal mariculture systems in Guangdong, China. Some of the V. alginolyticus strains are pathogenic to aquatic animals, and might have derived their virulence genes from V. parahaemolyticus or V. cholerae, representing a possible reservoir of these genes. However, there is no correlation between presence and absence of the virulence genes used to investigate V. alginolyticus and its virulent strains. In this report, we also show that tlh is distributed among V. alginolyticus.


Subject(s)
Genes, Bacterial , Seawater/microbiology , Vibrio alginolyticus/genetics , Vibrio alginolyticus/pathogenicity , Vibrio parahaemolyticus/genetics , Vibrio parahaemolyticus/pathogenicity , China , Virulence/genetics
7.
Pharmazie ; 58(10): 756-8, 2003 Oct.
Article in English | MEDLINE | ID: mdl-14609292

ABSTRACT

Two new cyclopeptides, leiocyclocin C (1) and D (2), were isolated from the seeds of Goniothalamus leiocarpus (Annonaceae). Their structures were determined as cyclo-(Gly1-Ser-Pro2-Tyr2-Gly2-Tyr1-Pro1-Pro3) and cyclo-(Gly1-Leu-Pro1-Gly2-Phe-Tyr-Pro2), respectively, by means of spectral and chemical methods.


Subject(s)
Annonaceae/chemistry , Peptides, Cyclic/chemistry , Magnetic Resonance Spectroscopy , Plant Extracts/analysis , Spectrometry, Mass, Fast Atom Bombardment
9.
Yao Xue Xue Bao ; 36(4): 278-80, 2001 Apr.
Article in Chinese | MEDLINE | ID: mdl-12580056

ABSTRACT

AIM: To study the chemical components of the root of Clematis chinensis. METHODS: Various chromatographic techniques were used to separate and purify the components. Their structures were determined on the basis of spectral and chemical evidence. RESULTS: Two compounds were isolated and elucidated as: clemaphenol A (I) and dihydro-4-hydroxy-5-hyroxymethy-2(3H)- furanone (II). CONCLUSION: Compound I and II are new compounds.


Subject(s)
4-Butyrolactone/isolation & purification , Anisoles/isolation & purification , Clematis/chemistry , Furans/isolation & purification , Plants, Medicinal/chemistry , 4-Butyrolactone/analogs & derivatives , 4-Butyrolactone/chemistry , Anisoles/chemistry , Furans/chemistry , Molecular Structure , Plant Roots/chemistry
10.
Bioorg Med Chem Lett ; 9(23): 3319-24, 1999 Dec 06.
Article in English | MEDLINE | ID: mdl-10612592

ABSTRACT

Twenty-six beta-carbolines were evaluated for in vitro cytotoxicity in a human tumor cell line panel. Harmine (3) showed significant activity against several cell lines including three drug-resistant KB sublines with various resistance mechanisms. Alpha-(4-nitrobenzylidine) harmine (16) had a broad cytotoxicity spectrum (ED50 values from 0.3-1.2 microg/mL against 1A9, KB, SaOS-2, A549, SK-MEL-2, U-87-MG, and MCF-7 cells).


Subject(s)
Antineoplastic Agents/pharmacology , Carbolines/pharmacology , Harmine/pharmacology , Antineoplastic Agents/chemistry , Carbolines/chemistry , Drug Screening Assays, Antitumor , Harmine/chemistry , Humans , Tumor Cells, Cultured
11.
J Nat Prod ; 61(9): 1090-5, 1998 Sep.
Article in English | MEDLINE | ID: mdl-9748372

ABSTRACT

Oleanolic acid (1) was identified as an anti-HIV principle from several plants, including Rosa woodsii (leaves), Prosopis glandulosa (leaves and twigs), Phoradendron juniperinum (whole plant), Syzygium claviflorum (leaves), Hyptis capitata (whole plant), and Ternstromia gymnanthera (aerial part). It inhibited HIV-1 replication in acutely infected H9 cells with an EC50 value of 1.7 microg/mL, and inhibited H9 cell growth with an IC50 value of 21.8 microg/mL [therapeutic index (T. I.) 12.8]. Pomolic acid, isolated from R. woodsii and H. capitata, was also identified as an anti-HIV agent (EC50 1.4 microg/mL, T. I. 16.6). Although ursolic acid did show anti-HIV activity (EC50 2.0 microg/mL), it was slightly toxic (IC50 6.5 microg/mL, T. I. 3.3). A new triterpene (11) was also isolated from the CHCl3-soluble fraction of R. woodsii, though it showed no anti-HIV activity. The structure of 11 was determined to be 1beta-hydroxy-2-oxopomolic acid by spectral examination. Based on these results, we examined the anti-HIV activity of oleanolic acid- or pomolic acid-related triterpenes isolated from several plants. In addition, we previously demonstrated that derivatives of betulinic acid, isolated from the leaves of S. claviflorum as an anti-HIV principle, exhibited extremely potent anti-HIV activity. Accordingly, we prepared derivatives of oleanolic acid and evaluated their anti-HIV activity. Among the oleanolic acid derivatives, 18 demonstrated most potent anti-HIV activity, with an EC50 value of 0. 0005 microg/mL and a T. I. value of 22 400.


Subject(s)
Anti-HIV Agents/pharmacology , Oleanolic Acid/analogs & derivatives , Oleanolic Acid/pharmacology , Triterpenes/pharmacology , Anti-HIV Agents/chemistry , Anti-HIV Agents/isolation & purification , Cell Line , Humans , Oleanolic Acid/chemistry , Oleanolic Acid/isolation & purification , Plants, Medicinal/chemistry , Triterpenes/chemistry , Triterpenes/isolation & purification , Viral Plaque Assay
12.
Yao Xue Xue Bao ; 32(7): 553-7, 1997 Jul.
Article in Chinese | MEDLINE | ID: mdl-11596284

ABSTRACT

Sultamicillin is an oral mutual pro-drug composed of double esters of formaldehyde hydrate in which one of the hydroxyl groups is esterified with ampicillin and the other with sulbactam. It is hydrolyzed fast in neutral or weakly alkaline condition. When hydrolyzed, it forms ampicillin and hydroxylmethyl sulbactam or sulbactam and hydroxylmethyl ampicillin by different routes. Usually, the former has priority as the two ester bonds have different activities. The ratio of ampicillin to sulbactam in the products is about 3:1. Both the hydroxylmethyl sulbactam and the hydroxylmethyl ampicillin can be further catalyzed by esterase to produce formaldehyde.


Subject(s)
Ampicillin/chemistry , Prodrugs/chemistry , Sulbactam/chemistry , Ampicillin/analysis , Drug Therapy, Combination , Hydrolysis , Sulbactam/analysis
13.
J Nat Prod ; 58(11): 1647-54, 1995 Nov.
Article in English | MEDLINE | ID: mdl-8594141

ABSTRACT

Two pleiotropic multi-drug resistant (PDR) KB cell lines were hypersusceptible to a cytotoxic extract from Fatsia japonica. Fractionation of an active extract using a cell-based assay for DNA topoisomerase inhibitors led to the isolation of three known triterpene glycosides, FJ-1-3 [1-3]. The structures of 1-3 were identified as 3-O-alpha-L-arabinopyranosyl-oleanolic acid [1], 3-O-alpha-L-arabinopyranosyl-hederagenin [2], and 3-O-[beta-D-glucopyranosyl(1-->4)-alpha-L-arabinopyranosyl]-hed eragenin [3], respectively. However, these isolates were not DNA topoisomerase II inhibitors in vitro and nor were they active when re-tested for differential cytotoxicity. Compounds 1-3 appear to function by interfering selectively with cellular drug accumulation. Other fractions probably contained compounds active against DNA topoisomerase I; however, the enriched preparations were not cytotoxic. The present findings indicate a simple modification to improve the cell-based bioassay procedure employed to guide fractionation.


Subject(s)
Antineoplastic Agents, Phytogenic/isolation & purification , Drugs, Chinese Herbal/pharmacology , Enzyme Inhibitors/isolation & purification , Oleanolic Acid/analogs & derivatives , Saponins/isolation & purification , Topoisomerase II Inhibitors , Antineoplastic Agents, Phytogenic/pharmacology , Antineoplastic Agents, Phytogenic/toxicity , Cell Division/drug effects , Drug Resistance, Neoplasm , Drug Screening Assays, Antitumor , Drugs, Chinese Herbal/chemistry , Drugs, Chinese Herbal/toxicity , Enzyme Inhibitors/pharmacology , Enzyme Inhibitors/toxicity , Humans , Hydrolysis , KB Cells , Oleanolic Acid/isolation & purification , Oleanolic Acid/pharmacology , Oleanolic Acid/toxicity , Plant Leaves/chemistry , Saponins/pharmacology , Saponins/toxicity
14.
Bioorg Med Chem ; 3(10): 1345-8, 1995 Oct.
Article in English | MEDLINE | ID: mdl-8564400

ABSTRACT

A new kaurane type diterpene lactone, neotripterifordin (1), has been isolated from the roots of Tripterygium wilfordii. The structure of 1 was elucidated by spectroscopic methods, which included the concerted application of a number of 2-D NMR techniques including 1H-1H COSY, phase-sensitive NOESY, HETCOR, and long-range HETCOR. Compound 1 showed potent anti-HIV replication activity in H9 lymphocyte cells with an EC50 of 25 nM and TI of 125.


Subject(s)
Antiviral Agents/isolation & purification , Antiviral Agents/pharmacology , Diterpenes/isolation & purification , HIV-1/drug effects , Plants, Toxic/chemistry , Animals , Cattle , Cells, Cultured , China , Diterpenes/pharmacology , Humans , Lymphocytes/drug effects , Lymphocytes/virology , Mass Spectrometry , Plant Extracts/chemistry , Plant Extracts/pharmacology , Plant Roots/chemistry , Spectrophotometry, Infrared , Virus Replication/drug effects
15.
Planta Med ; 61(1): 41-4, 1995 Feb.
Article in English | MEDLINE | ID: mdl-7700990

ABSTRACT

The oligomeric stilbenes (+)-alpha-viniferin (1), miyabenol C (2), and kobophenol A (3) have been isolated from Caragana sinica (Buchoz) Rehd (Leguminosae). (+)-alpha-Viniferin (1) and miyabenol C (2) exhibited protein kinase C inhibitory activity at low micromolar concentrations. (+)-alpha-Viniferin inhibited keratinocyte proliferation (0.4 microM) and free radical release in whole blood (47 microM), in vitro, and may be useful in treating hyperproliferative or inflammatory skin diseases.


Subject(s)
Drugs, Chinese Herbal/chemistry , Protein Kinase C/antagonists & inhibitors , Stilbenes/pharmacology , Cells, Cultured , Drugs, Chinese Herbal/pharmacology , Humans , Magnetic Resonance Spectroscopy , Stilbenes/isolation & purification
16.
Article in Chinese | MEDLINE | ID: mdl-8044907

ABSTRACT

From 1989 to 1990, an investigation was conducted in three villages in Junsan township, Hanyang County, Hubei Province. The results showed that the infection rates of local residents were 55.1%, 49.5% and 44.3%, respectively; the EPG were 5.6, 5.2 and 2.0, respectively; the relative transmission index (RTI) were 7.1%, being highest in the age group 30-39 years. The relative index of potential contamination (IPC) was 67.2% in the age group 20-49 years, this group was considered as the main transmission source in the population. In animal hosts buffaloes, pigs and dogs, the infection rates were 35.7%, 60.0% and 75.0%, respectively; MPG (miracidium per gram), 0.4, 0.4 and 80.4, respectively; RTI (relative transmission index), 38.6%, 7.7 and 46.6%, respectively. The infection rates of pigs and dogs were high in Huangshi village, while the infection rate of buffaloes was high in Chuangjiang village. These results coincided with the transmission of schistosomiasis in these villages. The results showed that dogs as the main transmission sources had important significance in the epidemiology of schistosomiasis and that buffaloes and pigs herd and fed in the snail-habitats could be heavily infected.


Subject(s)
Buffaloes/parasitology , Disease Reservoirs , Dogs/parasitology , Schistosomiasis japonica/transmission , Swine/parasitology , Adolescent , Adult , Animals , Child , Child, Preschool , China/epidemiology , Female , Host-Parasite Interactions , Humans , Male , Middle Aged , Parasite Egg Count , Schistosomiasis japonica/epidemiology
17.
Yao Xue Xue Bao ; 29(11): 818-22, 1994.
Article in Chinese | MEDLINE | ID: mdl-7863783

ABSTRACT

The effect of 15 stilbenoids on protein kinase C (PKC) was studied in order to search for naturally occurring PKC inhibitors. All these compounds were isolated from Chinese medicines. Three oligomeric stilbenes from Caragana sinica, alpha-viniferin, kobophenol A and miyabenol C, were shown to intensely inhibit the activity of partially purified rat brain PKC with IC50 values of 62.5, 52.0, and 27.5 mumol.L-1, respectively. Kinetic analyses revealed that that inhibition was noncompetitive. The other compounds also showed the effect. Monomer stilbenes exhibited PKC inhibitory activity at higher mumol.L-1 concentrations than oligomeric stilbenes. Whenever they are methylated or acetylated perfectly, the inhibition weakens or disappears.


Subject(s)
Protein Kinase C/antagonists & inhibitors , Stilbenes/pharmacology , Animals , Brain Chemistry , Drugs, Chinese Herbal/chemistry , Male , Protein Kinase C/isolation & purification , Protein Kinase C/metabolism , Rats , Stilbenes/isolation & purification
18.
J Nat Prod ; 57(1): 42-51, 1994 Jan.
Article in English | MEDLINE | ID: mdl-8158164

ABSTRACT

An active anti-HIV principle, acacetin-7-O-beta-D-galactopyranoside, has been isolated from Chrysanthemum morifolium. Seven additional flavonoids isolated from this plant, 13 known related flavonoids, and 14 synthetic flavonoids were also evaluated as inhibitors of HIV replication in H9 cells. A known flavone, chrysin, was found to be the most promising compound in this series. Flavonoids with hydroxy groups at C-5 and C-7 and with a C-2-C-3 double bond were more potent inhibitors of HIV growth. In general, the presence of substituents (hydroxyl and halogen) in the B-ring increased toxicity and/or decreased activity.


Subject(s)
Antiviral Agents/isolation & purification , Flavonoids/isolation & purification , Flavonoids/pharmacology , Galactosides/isolation & purification , HIV-1/drug effects , Plants, Medicinal/chemistry , Antiviral Agents/pharmacology , Cells, Cultured , Galactosides/pharmacology , Humans , Mass Spectrometry , Medicine, Chinese Traditional , Spectrophotometry, Infrared , Spectrophotometry, Ultraviolet , Structure-Activity Relationship , Virus Replication/drug effects , Zidovudine/pharmacology
19.
Biochemistry ; 31(44): 10699-702, 1992 Nov 10.
Article in English | MEDLINE | ID: mdl-1420185

ABSTRACT

In continuation of our earlier work on the effects of amino acid replacements on the thermodynamics of the thermal unfolding of T4 lysozyme [Kitamura, S., & Sturtevant, J. M. (1989) Biochemistry 28, 3788-3792; Connelly, P., Ghosaini, L., Hu, C.-Q., Kitamura, S., Tanaka, A., & Sturtevant, J. M. (1991) Biochemistry 30, 1887-1891; Hu, C.-Q., Kitamura, S., Tanaka, A., & Sturtevant, J. M. (1992) Biochemistry 31, 1643-1647], we report here a study by differential scanning calorimetry of the effects of five replacements at Ile3. Four of these replacements, those with Glu, Phe, Pro, and Thr, caused apparent destabilizations, while the replacement by Leu led to a small apparent stabilization. The largest observed destabilization (Ile3Pro) amounted to -3.0 kcal mol-1 in free energy at pH 2.00 and 38.8 degrees C (the denaturational temperature of the wild-type protein at this pH), and the largest stabilization amounted to +1.2 kcal mol-1 at pH 3.00 and 53.6 degrees C.


Subject(s)
Bacteriophage T4/enzymology , Calorimetry, Differential Scanning , Hot Temperature , Muramidase/chemistry , Protein Folding , Bacteriophage T4/genetics , Enzyme Stability , Hydrogen-Ion Concentration , Muramidase/genetics , Mutation , Thermodynamics
20.
Biochemistry ; 31(20): 4876-82, 1992 May 26.
Article in English | MEDLINE | ID: mdl-1591247

ABSTRACT

Differential scanning calorimetry has been used to investigate the thermodynamics of denaturation of ribonuclease T1 as a function of pH over the pH range 2-10, and as a function of NaCl and MgCl2 concentration. At pH 7 in 30 mM PIPES buffer, the thermodynamic parameters are as follows: melting temperature, T1/2 = 48.9 +/- 0.1 degrees C; enthalpy change, delta H = 95.5 +/- 0.9 kcal mol-1; heat capacity change, delta Cp = 1.59 kcal mol-1 K-1; free energy change at 25 degrees C, delta G degrees (25 degrees C) = 5.6 kcal mol-1. Both T1/2 = 56.5 degrees C and delta H = 106.1 kcal mol-1 are maximal near pH 5. The conformational stability of ribonuclease T1 is increased by 3.0 kcal/mol in the presence of 0.6 M NaCl or 0.3 M MgCl2. This stabilization results mainly from the preferential binding of cations to the folded conformation of the protein. The estimates of the conformational stability of ribonuclease T1 from differential scanning calorimetry are shown to be in remarkably good agreement with estimates derived from an analysis of urea denaturation curves.


Subject(s)
Ribonuclease T1/chemistry , Thermodynamics , Calorimetry, Differential Scanning , Enzyme Stability , Hydrogen-Ion Concentration , Protein Conformation , Protein Denaturation , Spectrometry, Fluorescence
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