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1.
Cancer ; 130(4): 541-552, 2024 02 15.
Article in English | MEDLINE | ID: mdl-37843249

ABSTRACT

BACKGROUND: Based on a high incidence of genomic alteration in the cell cycle and DNA damage and response (DDR)-related pathways in small cell lung cancer (SCLC), the clinical efficacy of the DDR-targeting agent olaparib (PARP inhibitor) as monotherapy and in combination with ceralasertib (ATR inhibitor) in relapsed or refractory SCLC was evaluated. METHODS: As part of a phase 2 biomarker driven umbrella study, patients with SCLC and predefined DDR gene alterations who failed to benefit from prior platinum-based regimens were allocated to the olaparib monotherapy arm and nonbiomarker-selected patients were allocated to the olaparib and ceralasertib combination arm. RESULTS: In the olaparib monotherapy arm (n = 15), the objective response rate was 6.7% (one partial response), and the disease control rate was 33.3%, including three patients with stable disease. The median progression-free survival was 1.3 months (95% CI, 1.2-NA). In the combination arm (n = 26), the objective response rate and disease control rate were 3.8% and 42.3%, respectively, with one partial response and 10 patients with stable disease. The median progression-free survival was 2.8 months (95% CI, 1.8-5.4). Treatment was generally well tolerated except for one fatal case of neutropenic fever in the combination arm. CONCLUSIONS: Targeting DDR pathways with olaparib as a single agent or in combination with ceralasertib did not meet the predefined efficacy end point. However, disease stabilization was more evident in the combination arm. Further investigation of the combination of olaparib in SCLC should be performed with diverse combinations and patient selection strategies to maximize efficacy.


Subject(s)
Indoles , Lung Neoplasms , Morpholines , Ovarian Neoplasms , Piperazines , Pyrimidines , Small Cell Lung Carcinoma , Sulfonamides , Humans , Female , Small Cell Lung Carcinoma/drug therapy , Lung Neoplasms/drug therapy , Lung Neoplasms/genetics , Lung Neoplasms/chemically induced , Treatment Outcome , Phthalazines/adverse effects , Ovarian Neoplasms/drug therapy
2.
Gynecol Oncol ; 163(2): 246-253, 2021 11.
Article in English | MEDLINE | ID: mdl-34620496

ABSTRACT

OBJECTIVE: Platinum-resistant, high-grade serous ovarian cancer (HGSOC) has limited treatment options. Preclinical data suggest that poly(ADP-ribose) polymerase inhibitors (PARPi) and ataxia telangiectasia and Rad3-related kinase inhibitors (ATRi) are synergistic. CAPRI (NCT03462342) is an investigator-initiated study of olaparib plus ceralasertib in recurrent HGSOC. Herein, we present results from the platinum-resistant cohort. METHODS: A Simon 2-stage design was utilized. Platinum-resistant HGSOC patients received ceralasertib 160 mg orally daily, days 1-7 and olaparib 300 mg orally twice daily, days 1-28 of a 28-day cycle until toxicity or progression. Primary endpoints were toxicity and efficacy including objective response rate (ORR) by RECIST. Secondary endpoint was progression-free survival (PFS). The null hypothesis (≤5% ORR) would be rejected if there were ≥ 1 responses in 12 patients. RESULTS: Fourteen PARPi-naïve patients were evaluable for toxicity; 12 were evaluable for response. Three had BRCA1 mutations (1 germline, 2 somatic). Adverse events possibly related to treatment were primarily grade (G) 1/2. G3 toxicities included nausea (14.3%), fatigue (7.1%), anorexia (7.1%), and anemia (7.1%). No objective responses occurred. Best response was stable disease in 9 patients and progressive disease in three. Five patients had a ≥ 20% to <30% reduction in disease burden, including 3 with BRCA1 mutations. Three of 11 patients (27%; 2 with BRCA1 mutations) evaluable by Gynecologic Cancer Intergroup criteria had >50% CA-125 decline, including 2 with CA-125 normalization. Median PFS was 4.2 months overall (90% CI:3.5-8.2) and 8.2 months (3.6 months-not determined) for patients with BRCA1 mutations. CONCLUSIONS: Olaparib plus ceralasertib is well-tolerated. No objective responses occurred, though a signal of activity was seen particularly in disease associated with BRCA1. Further evaluation of this combination should include alternate dosing strategies in genomically-selected populations.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Indoles/adverse effects , Morpholines/adverse effects , Neoplasm Recurrence, Local/drug therapy , Ovarian Neoplasms/drug therapy , Phthalazines/administration & dosage , Piperazines/administration & dosage , Pyrimidines/adverse effects , Sulfonamides/adverse effects , Administration, Oral , Aged , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Ataxia Telangiectasia Mutated Proteins/antagonists & inhibitors , BRCA1 Protein/genetics , Drug Administration Schedule , Drug Resistance, Neoplasm , Female , Humans , Indoles/administration & dosage , Magnetic Resonance Imaging , Middle Aged , Morpholines/administration & dosage , Neoplasm Recurrence, Local/mortality , Neoplasm Recurrence, Local/pathology , Ovarian Neoplasms/diagnosis , Ovarian Neoplasms/genetics , Ovarian Neoplasms/mortality , Ovary/diagnostic imaging , Ovary/pathology , Phthalazines/adverse effects , Piperazines/adverse effects , Poly(ADP-ribose) Polymerase Inhibitors/administration & dosage , Poly(ADP-ribose) Polymerase Inhibitors/adverse effects , Progression-Free Survival , Protein Kinase Inhibitors , Pyrimidines/administration & dosage , Response Evaluation Criteria in Solid Tumors , Sulfonamides/administration & dosage , Tomography, X-Ray Computed
3.
Cancer ; 126(17): 4002-4012, 2020 09 01.
Article in English | MEDLINE | ID: mdl-32584426

ABSTRACT

BACKGROUND: A high percentage of small cell lung cancer (SCLC) cases harbor cell cycle-related gene mutations and RICTOR amplification. Based on underlying somatic mutations, the authors have conducted a phase 2 biomarker-driven, multiarm umbrella study. METHODS: The SCLC Umbrella Korea StudiES (SUKSES) is an adaptive platform trial that undergoes continual modification according to the observed outcomes. This study included 286 patients with SCLC who failed platinum therapy and who had known genomic profiles based on a predesigned screening trial. Patients with MYC amplification or CDKN2A and TP53 co-alterations were allocated to adavosertib (SUKSES protocol C [SUKSES-C]; 7 patients) and those with RICTOR amplification were allocated to vistusertib (SUKSES-D; 4 patients). Alternatively, patients who were without any predefined biomarkers were assigned to a non-biomarker-selected arm: adavosertib (SUKSES-N1; 21 patients) or AZD2811NP (SUKSES-N3; 15 patients). RESULTS: Patients in the SUKSES-C and SUKSES-N1 arms demonstrated no objective response. Three patients presented with stable disease (SD) in SUKSES-C and 6 patients in SUKSES-N1. The median progression-free survival (PFS) was 1.3 months (95% confidence interval, 0.9 months to not available) for SUKSES-C and 1.2 months (95% CI, 1.1-1.4 months) for SUKSES-N1. Patients in the SUKSES-D arm demonstrated no objective response and no SD, with a PFS of 1.2 months (95% CI, 1.0 months to not available). The SUKSES-N3 arm had 5 patients with SD and a PFS of 1.6 months (95% CI, 0.9-1.7 months), without an objective response. Grade≥3 adverse events (graded according to National Cancer Institute Common Terminology Criteria for Adverse Events [version 4.03]) were observed as follows: 3.2% in the SUKSES-C and SUKSES-N1 arms and 50.0% in the SUKSES-D arm. Target-related neutropenia (grade≥3) was observed in approximately 60.0% of patients in the AZD2811NP arm using the current dosing schedule. CONCLUSIONS: To the best of the authors' knowledge, the current study is the first biomarker-driven umbrella study conducted in patients with recurrent SCLC. Although the current study demonstrated the limited clinical efficacy of monotherapy, novel biomarker approaches using other cell cycle inhibitor(s) or combinations warrant further investigation.


Subject(s)
Cyclin-Dependent Kinase Inhibitor p16/genetics , Neoplasm Recurrence, Local/drug therapy , Proto-Oncogene Proteins c-myc/genetics , Small Cell Lung Carcinoma/drug therapy , Tumor Suppressor Protein p53/genetics , Adult , Aged , Aged, 80 and over , Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Benzamides/administration & dosage , Biomarkers, Tumor/genetics , Drug-Related Side Effects and Adverse Reactions , Female , Gene Amplification/drug effects , Humans , Male , Middle Aged , Morpholines/administration & dosage , Neoplasm Recurrence, Local/genetics , Neoplasm Recurrence, Local/pathology , Platinum/adverse effects , Progression-Free Survival , Pyrazoles/administration & dosage , Pyrimidines/administration & dosage , Pyrimidinones/administration & dosage , Rapamycin-Insensitive Companion of mTOR Protein/genetics , Small Cell Lung Carcinoma/genetics , Small Cell Lung Carcinoma/pathology
4.
Toxicol Appl Pharmacol ; 296: 10-8, 2016 Apr 01.
Article in English | MEDLINE | ID: mdl-26876616

ABSTRACT

Nausea and vomiting are components of a complex mechanism that signals food avoidance and protection of the body against the absorption of ingested toxins. This response can also be triggered by pharmaceuticals. Predicting clinical nausea and vomiting liability for pharmaceutical agents based on pre-clinical data can be problematic as no single animal model is a universal predictor. Moreover, efforts to improve models are hampered by the lack of translational animal and human data in the public domain. AZD3514 is a novel, orally-administered compound that inhibits androgen receptor signaling and down-regulates androgen receptor expression. Here we have explored the utility of integrating data from several pre-clinical models to predict nausea and vomiting in the clinic. Single and repeat doses of AZD3514 resulted in emesis, salivation and gastrointestinal disturbances in the dog, and inhibited gastric emptying in rats after a single dose. AZD3514, at clinically relevant exposures, induced dose-responsive "pica" behaviour in rats after single and multiple daily doses, and induced retching and vomiting behaviour in ferrets after a single dose. We compare these data with the clinical manifestation of nausea and vomiting encountered in patients with castration-resistant prostate cancer receiving AZD3514. Our data reveal a striking relationship between the pre-clinical observations described and the experience of nausea and vomiting in the clinic. In conclusion, the emetic nature of AZD3514 was predicted across a range of pre-clinical models, and the approach presented provides a valuable framework for predicition of clinical nausea and vomiting.


Subject(s)
Models, Animal , Nausea/chemically induced , Pyridazines/adverse effects , Receptors, Androgen/physiology , Vomiting/chemically induced , Animals , Dogs , Dose-Response Relationship, Drug , Drug Evaluation, Preclinical/methods , Female , Ferrets , Humans , Male , Nausea/blood , Nausea/diagnosis , Predictive Value of Tests , Rats , Rats, Wistar , Vomiting/blood , Vomiting/diagnosis
5.
J Pathol ; 232(2): 230-43, 2014 Jan.
Article in English | MEDLINE | ID: mdl-24114499

ABSTRACT

Targeted therapies provide clinical benefit and improved therapeutic index. They have a growing prominence in patient management and focus in drug development. Their development is fuelled by our deepening knowledge of complex disease phenotypes and the need for improvement in new therapeutic efficacy. Extrapolation of the biological discovery through to new therapy targeting the causal biological variants to drive clinical gain is challenging. Here, we review the impact of germline mutations on targeted therapies. Historically, germline changes have contributed most to our understanding of disease mechanisms, drug metabolism and exposure, the latter of which has enabled safer positioning of therapies, such as clopidogrel and irinotecan. Similarly, prescreening for germline variants can avoid potentially fatal hypersensitivity reactions with abacavir. However, germline mutations continue to emerge as a central player in targeting therapeutics; ivacaftor drives partial restoration of mucus secretion in cystic fibrosis patients harbouring specific mutations, and treatment with olaparib exploits germline mutations in BRCA genes to drive synthetic lethality as an anti-cancer mechanism. Central is definition of the causal link, association or contribution to the biological variance - and that we believe it is drugable for therapeutic gain. The demand for better therapies to treat modern diseases provides the appetite for continued investigation of the biological variance associated with germline mutations, inevitably leading to increased impact on the development of targeted therapeutics.


Subject(s)
Drug Design , Germ-Line Mutation , Molecular Targeted Therapy , Signal Transduction/drug effects , Signal Transduction/genetics , Animals , Drug-Related Side Effects and Adverse Reactions , Genetic Predisposition to Disease , Humans , Patient Selection , Phenotype , Precision Medicine
6.
J Clin Invest ; 134(2)2024 Jan 16.
Article in English | MEDLINE | ID: mdl-37934611

ABSTRACT

BACKGROUNDPhase 1 study of ATRinhibition alone or with radiation therapy (PATRIOT) was a first-in-human phase I study of the oral ATR (ataxia telangiectasia and Rad3-related) inhibitor ceralasertib (AZD6738) in advanced solid tumors.METHODSThe primary objective was safety. Secondary objectives included assessment of antitumor responses and pharmacokinetic (PK) and pharmacodynamic (PD) studies. Sixty-seven patients received 20-240 mg ceralasertib BD continuously or intermittently (14 of a 28-day cycle).RESULTSIntermittent dosing was better tolerated than continuous, which was associated with dose-limiting hematological toxicity. The recommended phase 2 dose of ceralasertib was 160 mg twice daily for 2 weeks in a 4-weekly cycle. Modulation of target and increased DNA damage were identified in tumor and surrogate PD. There were 5 (8%) confirmed partial responses (PRs) (40-240 mg BD), 34 (52%) stable disease (SD), including 1 unconfirmed PR, and 27 (41%) progressive disease. Durable responses were seen in tumors with loss of AT-rich interactive domain-containing protein 1A (ARID1A) and DNA damage-response defects. Treatment-modulated tumor and systemic immune markers and responding tumors were more immune inflamed than nonresponding.CONCLUSIONCeralasertib monotherapy was tolerated at 160 mg BD intermittently and associated with antitumor activity.TRIAL REGISTRATIONClinicaltrials.gov: NCT02223923, EudraCT: 2013-003994-84.FUNDINGCancer Research UK, AstraZeneca, UK Department of Health (National Institute for Health Research), Rosetrees Trust, Experimental Cancer Medicine Centre.


Subject(s)
Morpholines , Neoplasms , Pyrimidines , Sulfonamides , Humans , Neoplasms/drug therapy , Neoplasms/genetics , Neoplasms/pathology , Indoles , Inflammation/drug therapy , Genomics , Ataxia Telangiectasia Mutated Proteins/genetics
7.
Int J Exp Pathol ; 94(2): 156-68, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23441639

ABSTRACT

Marburg virus causes a highly infectious and lethal haemorrhagic fever in primates and may be exploited as a potential biothreat pathogen. To combat the infection and threat of Marburg haemorrhagic fever, there is a need to develop and license appropriate medical countermeasures. To determine whether the common marmoset (Callithrix jacchus) would be an appropriate model to assess therapies against Marburg haemorrhagic fever, initial susceptibility, lethality and pathogenesis studies were performed. Low doses of virus, between 4 and 28 TCID50 , were sufficient to cause a lethal, reproducible infection. Animals became febrile between days 5 and 6, maintaining a high fever before succumbing to disease between 8 and 11 days postchallenge. Typical signs of Marburg virus infection were observed including haemorrhaging and a transient rash. In pathogenesis studies, virus was isolated from the animals' lungs from day 3 postchallenge and from the liver, spleen and blood from day 5 postchallenge. Early signs of histopathology were apparent in the kidney and liver from day 3. The most striking features were observed in animals exhibiting severe clinical signs, which included high viral titres in all organs, with the highest levels in the blood, increased levels in liver function enzymes and blood clotting times, decreased levels in platelets, multifocal moderate-to-severe hepatitis and perivascular oedema.


Subject(s)
Callithrix , Disease Models, Animal , Inhalation Exposure , Marburg Virus Disease/pathology , Marburgvirus/pathogenicity , Monkey Diseases/pathology , Animals , Cytokines/metabolism , Disease Susceptibility , Female , Humans , Kidney/pathology , Kidney/virology , Liver/pathology , Liver/virology , Lung/pathology , Lung/virology , Male , Marburg Virus Disease/virology , Marburgvirus/isolation & purification , Monkey Diseases/virology , Spleen/pathology , Spleen/virology
8.
Clin Cancer Res ; 29(15): 2800-2807, 2023 08 01.
Article in English | MEDLINE | ID: mdl-37097611

ABSTRACT

PURPOSE: Addition of ataxia telangiectasia and Rad3-related kinase inhibitors (ATRi) to PARP inhibitors (PARPi) overcomes PARPi resistance in high-grade serous ovarian cancer (HGSOC) cell and mouse models. We present the results of an investigator-initiated study of combination PARPi (olaparib) and ATRi (ceralasertib) in patients with acquired PARPi-resistant HGSOC. PATIENTS AND METHODS: Eligible patients had recurrent, platinum-sensitive BRCA1/2 mutated or homologous recombination (HR)-deficient (HRD) HGSOC and clinically benefited from PARPi (response by imaging/CA-125 or duration of maintenance therapy; > 12 months first-line or > 6 months ≥ second-line) before progression. No intervening chemotherapy was permitted. Patients received olaparib 300 mg twice daily and ceralasertib 160 mg daily on days 1 to 7 of a 28-day cycle. Primary objectives were safety and objective response rate (ORR). RESULTS: Thirteen patients enrolled were evaluable for safety and 12 for efficacy; 62% (n = 8) had germline BRCA1/2 mutations, 23% (n = 3) somatic BRCA1/2 mutations, and 15% (n = 2) tumors with positive HRD assay. Prior PARPi indication was treatment for recurrence (54%, n = 7), second-line maintenance (38%, n = 5) and first-line treatment with carboplatin/paclitaxel (8%, n = 1). There were 6 partial responses yielding an ORR of 50% (95% confidence interval, 0.15-0.72). Median treatment duration was 8 cycles (range 4-23+). Grade (G) 3/4 toxicities were 38% (n = 5); 15% (n = 2) G3 anemia, 23% (n = 3) G3 thrombocytopenia, 8% (n = 1) G4 neutropenia. Four patients required dose reductions. No patient discontinued treatment due to toxicity. CONCLUSIONS: Combination olaparib and ceralasertib is tolerable and shows activity in HR-deficient platinum-sensitive recurrent HGSOC that benefited and then progressed with PARPi as the penultimate regimen. These data suggest that ceralasertib resensitizes PARPi-resistant HGSOCs to olaparib, warranting further investigation.


Subject(s)
Antineoplastic Agents , Ovarian Neoplasms , Animals , Female , Humans , Mice , Antineoplastic Agents/therapeutic use , Ataxia Telangiectasia Mutated Proteins/genetics , BRCA1 Protein/genetics , BRCA2 Protein/genetics , Carcinoma, Ovarian Epithelial/drug therapy , Homologous Recombination , Ovarian Neoplasms/drug therapy , Ovarian Neoplasms/genetics , Ovarian Neoplasms/pathology , Phthalazines , Poly(ADP-ribose) Polymerase Inhibitors/therapeutic use
9.
Clin Cancer Res ; 27(17): 4700-4709, 2021 09 01.
Article in English | MEDLINE | ID: mdl-33975862

ABSTRACT

PURPOSE: Ceralasertib is a potent and selective oral inhibitor of the serine/threonine protein kinase ataxia telangiectasia and Rad3-related (ATR) protein. PATIENTS AND METHODS: Eligible patients with solid tumors, enriched for melanoma, received ceralasertib in combination with a fixed dose of paclitaxel (80 mg/m2 on D1, D8, D15) in 28-day cycles. The dose of ceralasertib was escalated to reach an MTD in a rolling 6 design. The starting dose of ceralasertib was 40 mg QD. Fifty-seven patients (33 patients with melanoma who failed prior PD1/L1 treatment) were enrolled in 7 dose cohorts ranging from 40 mg QD to 240 mg BD plus weekly paclitaxel. RESULTS: The RP2D was established as ceralasertib 240 mg BD days 1-14 plus paclitaxel 80 mg/m2 on D1, D8, D15 every 28 days. The most common toxicities were neutropenia (n = 39, 68%), anemia (n = 25, 44%), and thrombocytopenia (n = 21, 37%). In the full analysis set of 57 patients, the overall response rate (ORR) was 22.6% (95% CI, 12.5-35.3). In 33 patients with melanoma, resistant to prior anti-PD1 therapy, the ORR was 33.3% (95% CI, 18.0-51.8). In the melanoma subset, the mPFS was 3.6 months (95% CI, 2.0-5.8), the median duration of response was 9.9 months (95% CI, 3.7-23.2), and the mOS was 7.4 months (95% CI, 5.7-11.9). CONCLUSIONS: Ceralasertib in combination with paclitaxel was well tolerated in patients with advanced malignancies and showed evidence of antitumor activity. Durable responses were observed in patients with advanced cutaneous, acral, and mucosal melanoma resistant to anti-PD1/L1 treatment.See related commentary by Ashworth, p. 4667.


Subject(s)
Antineoplastic Agents, Phytogenic/administration & dosage , Indoles/administration & dosage , Morpholines/administration & dosage , Neoplasms/drug therapy , Paclitaxel/administration & dosage , Pyrimidines/administration & dosage , Sulfonamides/administration & dosage , Adult , Aged , Drug Administration Schedule , Drug Combinations , Female , Humans , Male , Melanoma/drug therapy , Middle Aged , Skin Neoplasms/drug therapy
10.
Clin Cancer Res ; 27(19): 5213-5224, 2021 10 01.
Article in English | MEDLINE | ID: mdl-34301752

ABSTRACT

PURPOSE: This study reports the safety, tolerability, MTD, recommended phase II dose (RP2D), pharmacokinetic/pharmacodynamic profile, and preliminary antitumor activity of ceralasertib combined with carboplatin in patients with advanced solid tumors. It also examined exploratory predictive and pharmacodynamic biomarkers. PATIENTS AND METHODS: Eligible patients (n = 36) received a fixed dose of carboplatin (AUC5) with escalating doses of ceralasertib (20 mg twice daily to 60 mg once daily) in 21-day cycles. Sequential and concurrent combination dosing schedules were assessed. RESULTS: Two ceralasertib MTD dose schedules, 20 mg twice daily on days 4-13 and 40 mg once daily on days 1-2, were tolerated with carboplatin AUC5; the latter was declared the RP2D. The most common treatment-emergent adverse events (Common Terminology Criteria for Adverse Events grade ≥3) were anemia (39%), thrombocytopenia (36%), and neutropenia (25%). Dose-limiting toxicities of grade 4 thrombocytopenia (n = 2; including one grade 4 platelet count decreased) and a combination of grade 4 thrombocytopenia and grade 3 neutropenia occurred in 3 patients. Ceralasertib was quickly absorbed (tmax ∼1 hour), with a terminal plasma half-life of 8-11 hours. Upregulation of pRAD50, indicative of ataxia telangiectasia mutated (ATM) activation, was observed in tumor biopsies during ceralasertib treatment. Two patients with absent or low ATM or SLFN11 protein expression achieved confirmed RECIST v1.1 partial responses. Eighteen of 34 (53%) response-evaluable patients had RECIST v1.1 stable disease. CONCLUSIONS: The RP2D for ceralasertib plus carboplatin was established as ceralasertib 40 mg once daily on days 1-2 administered with carboplatin AUC5 every 3 weeks, with pharmacokinetic and pharmacodynamic studies confirming pharmacodynamic modulation and preliminary evidence of antitumor activity observed.


Subject(s)
Neoplasms , Neutropenia , Thrombocytopenia , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Ataxia Telangiectasia Mutated Proteins/genetics , Carboplatin , Humans , Indoles , Maximum Tolerated Dose , Morpholines , Neoplasms/etiology , Neutropenia/chemically induced , Nuclear Proteins , Protein Kinase Inhibitors/adverse effects , Pyrimidines , Sulfonamides , Sulfoxides , Thrombocytopenia/chemically induced
11.
Bioresour Technol ; 99(17): 8537-9, 2008 Nov.
Article in English | MEDLINE | ID: mdl-18424041

ABSTRACT

A new biogas meter was developed to satisfy the need for an adjustable resolution meter that has minimal back-pressure and wide flow rate capability. The new meter had three main components; a timed bellows pump that delivered fixed volumes, a pressure sensor, and a data logger. The meter was built from off-the-shelf components and was thus easy to build and cost effective. The meter also proved to be accurate, precise, sensitive, and simple to calibrate.


Subject(s)
Bioelectric Energy Sources , Biotechnology/instrumentation , Calibration , Pressure
12.
FEMS Microbiol Lett ; 250(1): 77-83, 2005 Sep 01.
Article in English | MEDLINE | ID: mdl-16040202

ABSTRACT

Caenorhabditis elegans has been used as a host for the study of bacteria that cause disease in mammals. However, a significant limitation of the model is that C. elegans is not viable at 37 degrees C. We report that the gonochoristic nematode Panagrellus redivivus survives at 37 degrees C and maintains its life cycle at temperatures up to and including 31.5 degrees C. The C. elegans pathogens Pseudomonas aeruginosa, Salmonella enterica, Staphylococcus aureus, but not Yersinia pseudotuberculosis, reduced P. redivivus lifespan. Of four strains of Burkholderia multivorans tested, one reduced P. redivivus lifespan at both temperatures, one was avirulent at both temperatures and two strains reduced P. redivivus lifespan only at 37 degrees C. The mechanism by which one of these strains killed P. redivivus at 37 degrees C, but not at 25 degrees C, was investigated further. Killing required viable bacteria, did not involve bacterial invasion of tissues, is unlikely to be due to a diffusible, bacterial toxin and was not associated with increased numbers of live bacteria within the intestine of the worm. We believe B. multivorans may kill P. redivivus by a temperature-regulated mechanism similar to B. pseudomallei killing of C. elegans.


Subject(s)
Bacteria/pathogenicity , Rhabditida/microbiology , Animals , Bacteria/isolation & purification , Bacteria/ultrastructure , Burkholderia/pathogenicity , Caenorhabditis elegans/microbiology , Female , Humans , Longevity , Male , Microscopy, Electron , Pseudomonas aeruginosa/pathogenicity , Rhabditida/ultrastructure , Salmonella enterica/pathogenicity , Species Specificity , Staphylococcus aureus/pathogenicity , Temperature , Virulence , Yersinia pseudotuberculosis/pathogenicity
13.
Chem Commun (Camb) ; 49(23): 2293-5, 2013 Mar 21.
Article in English | MEDLINE | ID: mdl-23407752

ABSTRACT

The dansyl fluorophore ligated to gold nanoparticles via imidazole and amine groups affords conjugates capable of detecting micromolar concentrations of the chemical warfare agent sulfur mustard by a fluorescence switching 'ON' displacement assay.


Subject(s)
Chemical Warfare Agents/analysis , Fluorescent Dyes/chemistry , Gold/chemistry , Metal Nanoparticles/chemistry , Mustard Gas/analysis , Phosphatidylcholines/chemistry , Spectrophotometry, Ultraviolet , Amines/chemistry , Imidazoles/chemistry
14.
Bioresour Technol ; 101(23): 9361-5, 2010 Dec.
Article in English | MEDLINE | ID: mdl-20685110

ABSTRACT

This work develops an alternative gas transfer calculation method to the two methods currently used in anaerobic digestion modelling. The current calculation methods are problematic because one is computationally stiff, while the other introduces an artificial overpressure. The new approach began by noting that the gas partial pressures are the same as the partial flows at the liquid/gas interface, and then used the self-consistency requirement to develop gas pressure equations which were used by a search algorithm. The new approach took about three iterations to achieve a flow precision better than 2x10(-7) mol h(-1) l(-1), and was self-consistent and stable even when working with eight gases.


Subject(s)
Gases/chemistry , Models, Chemical , Diffusion , Kinetics , Pressure , Steam/analysis , Temperature
15.
Gynecol Oncol ; 85(2): 255-9, 2002 May.
Article in English | MEDLINE | ID: mdl-11972384

ABSTRACT

OBJECTIVES: The aim of the study was to determine the prevalence of BRCA1 and BRCA2 germline mutations among ovarian cancer patients ascertained to have a family history of ovarian cancer. METHODS: Ovarian cancer patients were eligible if they had a family history of cancer that met any one of the following criteria: (1) a first-degree relative with ovarian cancer; (2) a second-degree relative with ovarian cancer plus a first-degree relative with breast cancer (diagnosed younger than 50 years of age); or (3) a first- and a second-degree relative with breast cancer (diagnosed younger than 50 years of age). The entire coding sequence of BRCA1 and exon 11 of BRCA2 were screened for germline alterations by single-strand conformation polymorphism analysis. RESULTS: Of 26 eligible patients screened for mutations, 12 had deleterious alterations, 8 in BRCA1 and 4 in BRCA2. A correlation was noted between the presence of a BRCA1 mutation and the strength of family history of breast ovarian cancer, with the likelihood of a mutation increasing with the number of affected relatives (P = 0.0002). No association was detected between the location of mutations in BRCA1 and the ratio of ovarian cancer cases relative to breast cancer (P = 0.28). CONCLUSIONS: Mutations in BRCA1 or BRCA2 are present in about 50% of ovarian cancer patients with at least one first-degree relative with disease, and in 70% of patients with two or more relatives with ovarian cancer.


Subject(s)
Genes, BRCA1 , Genes, BRCA2 , Germ-Line Mutation , Ovarian Neoplasms/genetics , Adult , Breast Neoplasms/genetics , Family Health , Female , Genetic Predisposition to Disease , Humans , Middle Aged , Risk Factors
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