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1.
Mol Metab ; 10: 66-73, 2018 04.
Article in English | MEDLINE | ID: mdl-29478918

ABSTRACT

OBJECTIVES: Type 2 diabetes (T2D) is associated with chronic, low grade inflammation. Activation of the NLRP3 inflammasome and secretion of its target interleukin-1ß (IL-1ß) have been implicated in pancreatic ß cell failure in T2D. Specific targeting of the NLRP3 inflammasome to prevent pancreatic ß cell death could allow for selective T2D treatment without compromising all IL-1ß-associated immune responses. We hypothesized that treating a mouse model of T2D with MCC950, a compound that specifically inhibits NLRP3, would prevent pancreatic ß cell death, thereby preventing the onset of T2D. METHODS: Diabetic db/db mice were treated with MCC950 via drinking water for 8 weeks from 6 to 14 weeks of age, a period over which they developed pancreatic ß cell failure. We assessed metabolic parameters such as body composition, glucose tolerance, or insulin secretion over the course of the intervention. RESULTS: MCC950 was a potent inhibitor of NLRP3-induced IL-1ß in vitro and was detected at high levels in the plasma of treated db/db mice. Treatment of pre-diabetic db/db mice with MCC950, however, did not prevent pancreatic dysfunction and full onset of the T2D pathology. When examining the NLRP3 pathway in the pancreas of db/db mice, we could not detect an activation of this pathway nor increased levels of its target IL-1ß. CONCLUSIONS: NLRP3 driven-pancreatic IL-1ß inflammation does not play a key role in the pathogenesis of the db/db murine model of T2D.


Subject(s)
Anti-Inflammatory Agents/therapeutic use , Diabetes Mellitus, Type 2/drug therapy , Hypoglycemic Agents/therapeutic use , Insulin-Secreting Cells/metabolism , NLR Family, Pyrin Domain-Containing 3 Protein/antagonists & inhibitors , Animals , Anti-Inflammatory Agents/pharmacology , Cells, Cultured , Diabetes Mellitus, Type 2/metabolism , Furans , Heterocyclic Compounds, 4 or More Rings/pharmacology , Heterocyclic Compounds, 4 or More Rings/therapeutic use , Hypoglycemic Agents/pharmacology , Indenes , Insulin-Secreting Cells/drug effects , Interleukin-1beta/metabolism , Mice , NLR Family, Pyrin Domain-Containing 3 Protein/genetics , NLR Family, Pyrin Domain-Containing 3 Protein/metabolism , Sulfonamides , Sulfones/pharmacology , Sulfones/therapeutic use
2.
Oncogene ; 36(24): 3417-3427, 2017 06 15.
Article in English | MEDLINE | ID: mdl-28092670

ABSTRACT

Recent evidence has implicated the transmembrane co-receptor neuropilin-1 (NRP1) in cancer progression. Primarily known as a regulator of neuronal guidance and angiogenesis, NRP1 is also expressed in multiple human malignancies, where it promotes tumor angiogenesis. However, non-angiogenic roles of NRP1 in tumor progression remain poorly characterized. In this study, we define NRP1 as an androgen-repressed gene whose expression is elevated during the adaptation of prostate tumors to androgen-targeted therapies (ATTs), and subsequent progression to metastatic castration-resistant prostate cancer (mCRPC). Using short hairpin RNA (shRNA)-mediated suppression of NRP1, we demonstrate that NRP1 regulates the mesenchymal phenotype of mCRPC cell models and the invasive and metastatic dissemination of tumor cells in vivo. In patients, immunohistochemical staining of tissue microarrays and mRNA expression analyses revealed a positive association between NRP1 expression and increasing Gleason grade, pathological T score, positive lymph node status and primary therapy failure. Furthermore, multivariate analysis of several large clinical prostate cancer (PCa) cohorts identified NRP1 expression at radical prostatectomy as an independent prognostic biomarker of biochemical recurrence after radiation therapy, metastasis and cancer-specific mortality. This study identifies NRP1 for the first time as a novel androgen-suppressed gene upregulated during the adaptive response of prostate tumors to ATTs and a prognostic biomarker of clinical metastasis and lethal PCa.


Subject(s)
Neuropilin-1/genetics , Neuropilin-1/metabolism , Prostatic Neoplasms, Castration-Resistant/mortality , Prostatic Neoplasms/drug therapy , Up-Regulation , Androgen Antagonists/therapeutic use , Cell Line, Tumor , Disease Progression , Epithelial-Mesenchymal Transition , Gene Expression Regulation, Neoplastic/drug effects , Humans , Male , Neoplasm Grading , Neoplasm Metastasis , Prostatic Neoplasms/genetics , Prostatic Neoplasms/mortality , Survival Analysis
3.
Eur J Med Chem ; 120: 353-62, 2016 Sep 14.
Article in English | MEDLINE | ID: mdl-27236016

ABSTRACT

Diarrhoeal diseases caused by the intestinal parasites Giardia lamblia and Entamoeba histolytica constitute a major global health burden. Nitroimidazoles are first-line drugs for the treatment of giardiasis and amebiasis, with metronidazole 1 being the most commonly used drug worldwide. However, treatment failures in giardiasis occur in up to 20% of cases and development of resistance to metronidazole is of concern. We have re-examined 'old' nitroimidazoles as a foundation for the systematic development of next-generation derivatives. Using this approach, derivatisation of the nitroimidazole carboxamide scaffold provided improved antiparasitic agents. Thirty-three novel nitroimidazole carboxamides were synthesised and evaluated for activity against G. lamblia and E. histolytica. Several of the new compounds exhibited potent activity against G. lamblia strains, including metronidazole-resistant strains of G. lamblia (EC50 = 0.1-2.5 µM cf. metronidazole EC50 = 6.1-18 µM). Other compounds showed improved activity against E. histolytica (EC50 = 1.7-5.1 µM cf. metronidazole EC50 = 5.0 µM), potent activity against Trichomonas vaginalis (EC50 = 0.6-1.4 µM cf. metronidazole EC50 = 0.8 µM) and moderate activity against the intestinal bacterial pathogen Clostridium difficile (0.5-2 µg/mL, cf. metronidazole = 0.5 µg/mL). The new compounds had low toxicity against mammalian kidney and liver cells (CC50 > 100 µM), and selected antiparasitic hits were assessed for human plasma protein binding and metabolic stability in liver microsomes to demonstrate their therapeutic potential.


Subject(s)
Antiparasitic Agents/pharmacology , Nitroimidazoles/pharmacology , Parasites/drug effects , Animals , Cells, Cultured , Drug Resistance , Drug Stability , Entamoeba histolytica/drug effects , Giardia lamblia/drug effects , Humans , Trichomonas vaginalis/drug effects
4.
Placenta ; 35(4): 260-8, 2014 Apr.
Article in English | MEDLINE | ID: mdl-24559727

ABSTRACT

INTRODUCTION: We have previously identified sex-specific differences in the fetal-placental response to cortisol. Our recent studies suggest that this differential response to cortisol is driven by differences in glucocorticoid receptor (GR) protein function rather than through changes in gene transcription or protein expression. METHODS: This study was designed to define whether the human placenta expresses different isoforms of the GR and whether expression was altered by fetal sex and maternal asthma. Asthma and non-asthma pregnant women were prospectively recruited at their first antenatal visit and placentae collected at delivery. Placental GR expression was examined in relation to maternal asthma, fetal sex and birthweight. RESULTS: Twelve specific bands for the GR were identified at molecular weights of 94, 91, 81, 74, 69, 68, 65, 60, 55, 50, 48 and 38 kDa. The 12 isoforms were localised to the placental trophoblast and expression varied in relation to cellular location in either the cytoplasm or nucleus, fetal sex, fetal size and the presence and absence of maternal asthma. CONCLUSION: This is the first study to identify the presence of several protein isoforms of the GR in the human placenta. The data suggest glucocorticoid resistance observed in male placentae may be mediated through increased GRß, GR A and GR P localisation to the nucleus. While female placentae may be more sensitive to cortisol in the presence of maternal asthma through a decrease in GRß and an enhancement GRα activity via an interaction with GRα D3 and GRα C.


Subject(s)
Asthma/metabolism , Placenta/metabolism , Pregnancy Complications/metabolism , Receptors, Glucocorticoid/metabolism , Sex Characteristics , Adrenal Cortex Hormones/therapeutic use , Adult , Asthma/drug therapy , Case-Control Studies , Female , Fetal Growth Retardation/metabolism , HEK293 Cells , Humans , Hydrocortisone/blood , Infant, Newborn , Male , Phosphorylation , Pregnancy , Pregnancy Complications/drug therapy , Protein Isoforms/metabolism
6.
Phytochemistry ; 58(8): 1235-8, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11738414

ABSTRACT

Bioassay-guided fractionation of a CHCl(3) extract from the leaves of Ardisia teysmanniana Scheff. (Myrsinaceae) has led to the isolation of three new alkyldibenzoquinone derivatives that showed inhibitory activity in an in vitro assay for UDP-MurNac synthesis. The structures of ardisiaquinone G, H and I were established using MS and NMR spectroscopic methods.


Subject(s)
Benzoquinones/chemistry , Primulaceae/chemistry , Benzoquinones/isolation & purification , Plant Leaves/chemistry
7.
J Nat Prod ; 64(1): 125-6, 2001 Jan.
Article in English | MEDLINE | ID: mdl-11170686

ABSTRACT

The crude extract of the broth of Aspergillus ochraceus was found to inhibit the final stage of polyprotein processing during hepatitis C virus replication. Bioassay-guided fractionation led to the isolation of the known compound mellein as the active component of the extract. Also isolated were circumdatin F and a new alkaloid, circumdatin G. The structure of circumdatin G was determined by spectroscopic analysis.


Subject(s)
Alkaloids/isolation & purification , Antiviral Agents/isolation & purification , Aspergillus ochraceus/chemistry , Ochratoxins/isolation & purification , Alkaloids/chemistry , Alkaloids/pharmacology , Antiviral Agents/chemistry , Antiviral Agents/pharmacology , Fermentation , Hepacivirus/drug effects , Hepacivirus/enzymology , Isocoumarins , Magnetic Resonance Spectroscopy , Ochratoxins/chemistry , Ochratoxins/pharmacology , Protease Inhibitors/chemistry , Protease Inhibitors/isolation & purification , Protease Inhibitors/pharmacology , Virus Replication/drug effects
8.
J Nat Prod ; 63(5): 688-9, 2000 May.
Article in English | MEDLINE | ID: mdl-10843590

ABSTRACT

Triunia erythrocarpa was identified as containing alkaloids during chemical screening of Queensland Proteaceae using Dragendorff's reagent. A new tropane, 10-hydroxydarlingine (1), and the known tropane, darlingine (2), were isolated from the leaves of T. erythrocarpa. The absolute stereochemistry of 10-hydroxydarlingine (1) was assigned using the advanced Mosher method. T. erythrocarpa is only the seventh member of the Proteaceae to have been shown to produce alkaloids.


Subject(s)
Alkaloids/chemistry , Plants/chemistry , Tropanes , Australia , Magnetic Resonance Spectroscopy , Mass Spectrometry , Plant Epidermis/chemistry , Plant Leaves/chemistry , Wood
9.
J Nat Prod ; 63(3): 318-21, 2000 Mar.
Article in English | MEDLINE | ID: mdl-10757710

ABSTRACT

The Australian sea pen Anthoptilum cf. kukenthali has afforded five new briarane-type diterpenes, anthoptilides A-E. Their structures were determined on the basis of their spectroscopic data. Single-crystal X-ray determination was performed on anthoptilide A. Anthoptilides B and C inhibited the binding of [(3)H]1, 3-dipropyl-8-cyclopentylxanthine ([(3)H]DPCPX) on adenosine A(1) receptors.


Subject(s)
Cnidaria/chemistry , Diterpenes/isolation & purification , Animals , Diterpenes/chemistry , Molecular Structure , Spectrum Analysis
10.
J Nat Prod ; 63(3): 393-5, 2000 Mar.
Article in English | MEDLINE | ID: mdl-10757728

ABSTRACT

Psammaplin A 11'-sulfate (3) and bisaprasin 11'-sulfate (4) have been isolated from the marine sponge Aplysinella rhax, along with the known psammaplin A (1). Their structures were determined on the basis of their spectroscopic data. Compounds 1 and 3 inhibited [(3)H]1,3-dipropyl-8-cyclopentylxanthine binding to rat-brain adenosine A(1) receptors.


Subject(s)
Porifera/chemistry , Sulfuric Acid Esters/isolation & purification , Tyrosine/analogs & derivatives , Animals , Molecular Structure , Rats , Spectrum Analysis , Sulfuric Acid Esters/chemistry , Tyrosine/chemistry , Tyrosine/isolation & purification
11.
J Nat Prod ; 59(10): 927-34, 1996 Oct.
Article in English | MEDLINE | ID: mdl-8904842

ABSTRACT

Further investigation of the Bismarck Archipelago (Papua New Guinea) marine sponge Ianthella basta for biologically active constituents has led to the isolation of hemibastadins 1 (2), 2 (3), and 3 (4) and the new brominated tyrosine derivatives hemibastadinols 1-3 (9, 13, and 14). Isolation and structure elucidation of the monomethyl ether derivatives (7 and 8) of hemibastadins 1 and 2 and the 3-bromotyramine amide of oxalic acid amide (1a) concluded our chemical investigation of I. basta. The hemibastadins and hemibastadinols represent important biosynthetic links to a series of bromotyrosine tetramers collectively known as the bastadins. The antimicrobial activity of the bastadins, hemibastadins, and hemibastadinols is summarized.


Subject(s)
Anti-Infective Agents/isolation & purification , Oximes/isolation & purification , Phenols/isolation & purification , Porifera/chemistry , Animals , Anti-Bacterial Agents , Anti-Infective Agents/chemistry , Anti-Infective Agents/pharmacology , Bacteria/drug effects , Chromatography, Liquid , Fungi/drug effects , Humans , Leukemia P388/drug therapy , Magnetic Resonance Spectroscopy , Microbial Sensitivity Tests , New Guinea , Oximes/chemistry , Oximes/pharmacology , Phenols/chemistry , Phenols/pharmacology , Spectrophotometry, Ultraviolet
13.
Percept Mot Skills ; 82(2): 527-30, 1996 Apr.
Article in English | MEDLINE | ID: mdl-8724926

ABSTRACT

The effectiveness of broad and narrow bandwidth feedback for learning a 2-segment timing task was tested over short-term (10-min.) and longer-term (2-day) retention intervals. The main finding was that bandwidth feedback groups deteriorated in accuracy across the retention tests, raising questions about the effectiveness of bandwidth feedback for longer-term learning.


Subject(s)
Feedback , Psychomotor Performance , Reaction Time , Retention, Psychology , Adult , Female , Goals , Humans , Knowledge of Results, Psychological , Male , Memory, Short-Term
14.
J Mot Behav ; 27(3): 241-250, 1995 Sep.
Article in English | MEDLINE | ID: mdl-12529235

ABSTRACT

Describing and analyzing error for one-dimensional performance tasks is fairly straightforward, but suggestions for describing and analyzing error for two-dimensional performance tasks (e.g., marksmanship) are quite problematic. Specifically, imposing an arbitrary axis onto the two-dimensional work space, along which traditional one-dimensional measures can be computed and analyzed, yields measures of accuracy, bias, and consistency that are entirely dependent upon the choice of axis. The present contribution offers new measures and methods for describing and analyzing data from two-dimensional performances. Unlike the resu1ts from previous suggestions, the approaches described herein yield results that are completely independent of the axes used to quantify the individual two-dimensional trials. These new approaches are strongly related to well-established methods for describing and analyzing error for one-dimensional tasks.

15.
J Nat Prod ; 58(5): 680-8, 1995 May.
Article in English | MEDLINE | ID: mdl-7623047

ABSTRACT

An investigation of cancer cell-growth inhibitory constituents of the Papua New Guinea marine sponge Ianthella basta led to isolation of the C-6 hydroxybastadins 8 [1] 10 [2], and 12 [3]. The absolute stereochemistry (6S) of each bastadin (or its tetramethyl ester derivative) was determined by means of the Mosher-Trost method. Bastadins 10 [2] and 12 [3] were found to significantly inhibit the growth of a selection of human cancer cell lines. Bastadins 8, 10, and 12 inhibited growth of the Gram-positive opportunists Staphylococcus aureus and Enterococcus faecalis.


Subject(s)
Antineoplastic Agents/chemistry , Phenyl Ethers/chemistry , Porifera/chemistry , Animals , Antineoplastic Agents/isolation & purification , Antineoplastic Agents/pharmacology , Cell Division/drug effects , Drug Screening Assays, Antitumor , Halogenated Diphenyl Ethers , Humans , Leukemia P388/drug therapy , Mice , Microbial Sensitivity Tests , Peptides, Cyclic , Phenyl Ethers/isolation & purification , Phenyl Ethers/pharmacology , Spectrum Analysis , Stereoisomerism , Tumor Cells, Cultured
16.
J Bone Joint Surg Am ; 73(10): 1492-502, 1991 Dec.
Article in English | MEDLINE | ID: mdl-1748698

ABSTRACT

A review of the data on 684 fractures of the femur that had been treated with intramedullary nailing led to the identification of twenty-three patients who had had a fracture of the shaft of the femur with an accompanying ipsilateral supracondylar fracture (twelve patients, group I) or a concomitant ipsilateral intercondylar fracture (eleven patients, group II). The group-I fractures had been treated with interlocking nailing without supplemental fixation. In group II, ten fractures were stabilized with interlocking nailing and supplemental screw fixation and one, with interlocking nailing and a supplemental plate and screws. The average time to union for all fractures was nineteen weeks (range, twelve to thirty-six weeks), and the average duration of clinical and radiographic follow-up was thirty months (range, nine to fifty-nine months). In group I, alignment of the femur was within 5 degrees of normal in ten of the twelve fractures. In group II, seven intra-articular fractures healed in anatomical alignment, three had slight articular displacement (1.0 to 3.0 millimeters), and one had displacement of more than 3.0 millimeters. The average range of motion of the knee at the most recent follow-up was 0 to 120 degrees in group I and 0 to 115 degrees in group II. Two patients (both in group II) needed a reoperation for a previously unrecognized fracture of a femoral condyle in the coronal plane; post-traumatic arthritis developed in both. No patient in either group had loss of fixation or failure of the implant. We concluded that ipsilateral diaphyseal, supracondylar, and intercondylar fractures of the femur can be adequately stabilized with interlocking nailing and supplemental intercondylar screw fixation. The presence of a fracture in the coronal plane of a femoral condyle (AO type-B3 and type-C3 injuries) is a relative contraindication to the use of this technique.


Subject(s)
Femoral Fractures/surgery , Fracture Fixation, Intramedullary , Fractures, Closed/surgery , Fractures, Open/surgery , Adolescent , Adult , Aged , Female , Femoral Fractures/diagnostic imaging , Humans , Knee Injuries/complications , Knee Injuries/diagnostic imaging , Male , Middle Aged , Radiography , Wound Healing
17.
J Pediatr Orthop ; 11(3): 284-7, 1991.
Article in English | MEDLINE | ID: mdl-2056074

ABSTRACT

Leg length inequality developed in 12 of 67 children who were treated with radiation therapy to the kidney, abdomen, pelvis, or lower extremities. All these children survived childhood cancer to the age of skeletal maturity. Of the 12 with anisomelia, seven were symptomatic. There were significant relationships between the development of leg length inequality and the total dose of radiation to the pelvic area, asymmetric irradiation to the pelvis, and high-dose irradiation to the leg.


Subject(s)
Leg Length Inequality/etiology , Radiotherapy/adverse effects , Abdomen , Adolescent , Child , Child, Preschool , Dose-Response Relationship, Radiation , Female , Follow-Up Studies , Humans , Infant , Leg/radiation effects , Male , Neoplasms/radiotherapy
18.
Med Pediatr Oncol ; 19(4): 265-8, 1991.
Article in English | MEDLINE | ID: mdl-1647490

ABSTRACT

Between 1970 and 1984, 31 children with biopsy-proven Wilms' tumor received nephrectomy, chemotherapy, and abdominal irradiation and were followed beyond skeletal maturity. Three patients (10%) developed late orthopedic abnormalities requiring intervention. Ten children received orthovoltage irradiation, and all cases requiring orthopedic intervention or developing a scoliotic curve of greater than 20 degrees were confined to this group, for a complication frequency of 50%. Those children who developed a significant late orthopedic abnormality (SLOA) as defined were treated to a higher median dose (2,890 cGy) and a larger field size (150 cm2) than those who did not (2,580 cGy and 120 cm2). Age at irradiation, sex, and initial stage of disease did not appear to influence the risk of developing an SLOA. No child who received megavoltage irradiation developed an SLOA despite treatment up to 4,000 cGy or to field sizes of 400 cm2. We conclude that modern radiotherapy techniques rarely lead to significant late orthopedic abnormalities previously associated with abdominal irradiation in children with Wilms' tumor.


Subject(s)
Bone Diseases, Developmental/etiology , Kidney Neoplasms/radiotherapy , Radiation Injuries , Spinal Diseases/etiology , Wilms Tumor/radiotherapy , Adolescent , Bone Diseases, Developmental/rehabilitation , Child , Child, Preschool , Female , Follow-Up Studies , Humans , Kyphosis/etiology , Male , Neoplasm Staging , Orthotic Devices , Radiotherapy Dosage , Retrospective Studies , Scoliosis/etiology , Spinal Diseases/rehabilitation
19.
Clin Orthop Relat Res ; (251): 235-40, 1990 Feb.
Article in English | MEDLINE | ID: mdl-2136823

ABSTRACT

One hundred forty-three patients who received radiation therapy for childhood tumors, and survived to the age of skeletal maturity, were studied by retrospective review of oncology records and roentgenograms. Diagnoses for the patients were the following: Hodgkin's lymphoma (44), Wilms's tumor (30), acute lymphocytic leukemia (26), non-Hodgkin's lymphoma (18), Ewing's sarcoma (nine), rhabdomyosarcoma (six), neuroblastoma (six), and others (four). Age at the follow-up examination averaged 18 years (range, 14-28 years). Average length of follow-up study was 9.9 years (range, two to 18 years). Asymmetry of the chest and ribs was seen in 51 (36%) of these children. Fifty (35%) had scoliosis; 14 had kyphosis. In two children, the scoliosis was treated with a brace, while one developed significant kyphosing scoliosis after laminectomy and had spinal fusion. Twenty-three (16%) patients complained of significant pain at the radiation sites. Twelve of the patients developed leg-length inequality; eight of those were symptomatic. Three patients developed second primary tumors. Currently, the incidence of significant skeletal sequelae is lower and the manifestations are less severe than reported in the years from 1940 to 1970. The reduction in skeletal complications may be attributed to shielding of growth centers, symmetric field selection, decreased total radiation doses, and sequence changes in chemotherapy.


Subject(s)
Bone Diseases/etiology , Neoplasms/radiotherapy , Radiation Injuries/etiology , Spinal Diseases/etiology , Adolescent , Adult , Back Pain/etiology , Combined Modality Therapy , Female , Follow-Up Studies , Humans , Leg Length Inequality/etiology , Male , Neoplasms, Radiation-Induced/etiology , Retrospective Studies , Spinal Diseases/therapy , Spinal Fusion
20.
Opt Lett ; 12(3): 166-8, 1987 Mar 01.
Article in English | MEDLINE | ID: mdl-19738827

ABSTRACT

An experimental investigation of a longitudinally excited Ca(+) discharge-recombination laser with an active volume of 1000 cm(3) is reported. Single-pulse output energy densities greater than 4 microJ/cm(3) at energy-conversion efficiencies of 0.05% have been obtained on the lambda373.7-nm transition for low-pulse-rate (1-Hz) operation at helium buffergas pressures up to 400 Torr. Mean powers greater 0.5 W have been obtained at 500 Hz in preliminary studies of high-pulse-rate operation.

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