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1.
J Endourol ; 37(6): 718-728, 2023 06.
Article in English | MEDLINE | ID: mdl-37029790

ABSTRACT

Objective: Surgical outcomes are dependent on multiple factors. Besides patient-related or procedure-related factors, several surgeon-related factors contribute to surgical outcomes. The Surgery Task Load Index (SURG-TLX) questionnaire helps to assess the impact of several stressors on the perceived demands of surgeons during surgery. In this study, we evaluate the applicability of the SURG-TLX questionnaire for endourologic procedures and set a first point of reference. Materials and Methods: Between March and August 2022, 15 urologists and urology residents at a tertiary referral center for endourology completed the SURG-TLX questionnaire after endourologic procedures. After data acquisition, all participants were asked to evaluate the applicability of the questionnaire for endourologic procedures. Results: A total of 130 procedures were included between March and August 2022. Situational stress had the lowest median score (3.0/20; interquartile range [IQR] 2.0-7.0) and task complexity the highest (5.0/20; IQR 3.0-8.0). After weighing, the dimensions showed different proportions when compared with the nonweighted scores. Distractions received the highest score (15.0/100; IQR 7.5-32.8), temporal demands (6.0/100; IQR 3.0-12.5), and situational stress the lowest (6.0/100; IQR 2.0-21.0). This was caused by the higher weight that was attributed to distractions (3.4/5), as opposed to task complexity (2.6/5). In the questionnaire regarding applicability of the SURG-TLX, the overall satisfaction (6.0/10; IQR 5.0-7.0) and clarity (6.5/10; IQR 5.0-7.5) were moderate. The user-friendliness and applicability of the questionnaire were rated high (7.0/10; IQR 5.5-8.0 and 7.0/10; IQR 6.0-8.0, respectively) and task load (3.0/10; IQR 2.0-5.0) and time load (2.0/10; IQR 2.0-3.5) low. Conclusion: The SURG-TLX questionnaire is appropriate to assess the different dimensions of workload during endourologic procedures. Furthermore, the perceived workload during endourologic procedures is relatively low.


Subject(s)
Laparoscopy , Surgeons , Humans , Workload , Surveys and Questionnaires , Clinical Competence
2.
Eur Urol Focus ; 4(6): 978-985, 2018 12.
Article in English | MEDLINE | ID: mdl-29079496

ABSTRACT

BACKGROUND: Lack of accuracy in preoperative imaging leads to overtreatment of benign renal masses (RMs) or indolent renal cell carcinomas (RCCs). Optical coherence tomography (OCT) is real time and high resolution, enabling quantitative analysis through attenuation coefficient (µOCT, mm-1). OBJECTIVE: To determine the accuracy and diagnostic yield of OCT and renal mass biopsy (RMB) for the differentiation of benign RMs versus RCC and oncocytoma versus RCC. DESIGN, SETTING, AND PARTICIPANTS: From October 2013 to June 2016, 95 patients with solid enhancing RMs on cross-sectional imaging were prospectively included. All patients underwent subsequent excision or ablation. INTERVENTION: Percutaneous, image-guided, needle-based OCT followed by RMB in an outpatient setting under local anaesthesia. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Accuracy and diagnostic yield, µOCT correlated to resection pathology or second biopsy during ablation. Tables (2×2) for RMB, receiver operating characteristic curve for OCT. Mann-Whitney test to differentiate µOCT of RMs. RESULTS AND LIMITATIONS: RMB diagnostic yield was 79% with sensitivity, specificity, positive predictive value, and negative predictive value (NPV) of 100%, 89%, 99%, and 100%, respectively. Diagnostic yield and added value of OCT to differentiate RCC from benign was 99% and 15%, respectively. Significant difference was observed in median µOCT between benign RMs (3.2mm-1, interquartile range [IQR]: 2.65-4.35) and RCCs (4.3mm-1, IQR: 3.70-5.00), p=0.0171, and oncocytomas (3.38mm-1, IQR: 2.68-3.95) and RCCs (4.3mm-1, IQR: 3.70-5.00), p=0.0031. OCT showed sensitivity, specificity, positive predictive value. and NPV of 91%, 56%, 91%, and 56%, respectively, to differentiate benign RMs from RCCs and 92%, 67%, 95%, and 55%, respectively, to differentiate oncocytoma from RCC. Limitations include two reference standards and heterogeneity benign RMs. CONCLUSIONS: Compared with RMB, OCT has a higher diagnostic yield. OCT accurately distinguishes benign RMs from RCCs, and oncocytoma from RCCs, although specificity and NPV are lower. PATIENT SUMMARY: Optical coherence tomography, a new optical scan, exhibits similar sensitivity and positive predictive value than renal mass biopsy, although lower specificity and negative predictive value. Optical coherence tomography has a higher diagnostic yield for diagnosing renal cell carcinoma.


Subject(s)
Adenoma, Oxyphilic/diagnostic imaging , Carcinoma, Renal Cell/diagnostic imaging , Kidney Neoplasms/diagnostic imaging , Adenoma/diagnostic imaging , Adenoma/pathology , Adenoma, Oxyphilic/pathology , Adenoma, Oxyphilic/surgery , Adult , Aged , Biopsy , Carcinoma, Renal Cell/pathology , Carcinoma, Renal Cell/surgery , Cryosurgery , Cysts/diagnostic imaging , Cysts/pathology , Female , Granulation Tissue/diagnostic imaging , Granulation Tissue/pathology , Hemangioma/diagnostic imaging , Hemangioma/pathology , Humans , Kidney Neoplasms/pathology , Kidney Neoplasms/surgery , Leiomyoma/diagnostic imaging , Leiomyoma/pathology , Male , Middle Aged , Nephrectomy , Predictive Value of Tests , Prospective Studies , ROC Curve , Sensitivity and Specificity , Tomography, Optical Coherence
3.
Angew Chem Int Ed Engl ; 56(3): 827-831, 2017 01 16.
Article in English | MEDLINE | ID: mdl-27966810

ABSTRACT

The p300/CBP-associated factor (PCAF) and related GCN5 bromodomain-containing lysine acetyl transferases are members of subfamily I of the bromodomain phylogenetic tree. Iterative cycles of rational inhibitor design and biophysical characterization led to the discovery of the triazolopthalazine-based L-45 (dubbed L-Moses) as the first potent, selective, and cell-active PCAF bromodomain (Brd) inhibitor. Synthesis from readily available (1R,2S)-(-)-norephedrine furnished L-45 in enantiopure form. L-45 was shown to disrupt PCAF-Brd histone H3.3 interaction in cells using a nanoBRET assay, and a co-crystal structure of L-45 with the homologous Brd PfGCN5 from Plasmodium falciparum rationalizes the high selectivity for PCAF and GCN5 bromodomains. Compound L-45 shows no observable cytotoxicity in peripheral blood mononuclear cells (PBMC), good cell-permeability, and metabolic stability in human and mouse liver microsomes, supporting its potential for in vivo use.


Subject(s)
Azo Compounds/pharmacology , Drug Discovery , Hydralazine/pharmacology , Molecular Probes/pharmacology , p300-CBP Transcription Factors/antagonists & inhibitors , Azo Compounds/chemical synthesis , Azo Compounds/chemistry , Dose-Response Relationship, Drug , Hydralazine/chemical synthesis , Hydralazine/chemistry , Molecular Probes/chemical synthesis , Molecular Probes/chemistry , Molecular Structure , Structure-Activity Relationship
4.
Drug Discov Today Technol ; 19: 73-80, 2016 Mar.
Article in English | MEDLINE | ID: mdl-27769361

ABSTRACT

The bromodomain family of proteins are 'readers' of acetylated lysines of histones, a key mark in the epigenetic code of gene regulation. Without high quality chemical probes with which to study these proteins, their biological function, and potential use in therapeutics, remains unknown. Recently, a number of chemical ligands were reported for the previously unprobed bromodomain proteins BRD7 and BRD9. Herein the development and characterisation of probes against these proteins is detailed, including the preliminary biological activity of BRD7 and BRD9 assessed using these probes. Future studies utilising these chemically-diverse compounds in parallel will allow for a confident assessment of the role of BRD7/9, and give multiple entry points into any subsequent pharmaceutical programs.


Subject(s)
Chromosomal Proteins, Non-Histone/chemistry , Protein Domains , Transcription Factors/chemistry , Animals , Chromosomal Proteins, Non-Histone/metabolism , Drug Design , Humans , Ligands , Transcription Factors/metabolism
5.
Oncotarget ; 7(28): 43997-44012, 2016 Jul 12.
Article in English | MEDLINE | ID: mdl-27259267

ABSTRACT

Gastric cancer is one of the most common malignancies and a leading cause of cancer death worldwide. The prognosis of stomach cancer is generally poor as this cancer is not very sensitive to commonly used chemotherapies. Epigenetic modifications play a key role in gastric cancer and contribute to the development and progression of this malignancy. In order to explore new treatment options in this target area we have screened a library of epigenetic inhibitors against gastric cancer cell lines and identified inhibitors for the BET family of bromodomains as potent inhibitors of gastric cancer cell proliferations. Here we show that both the pan-BET inhibitor (+)-JQ1 as well as a newly developed specific isoxazole inhibitor, PNZ5, showed potent inhibition of gastric cancer cell growth. Intriguingly, we found differences in the antiproliferative response between gastric cancer cells tested derived from Brazilian patients as compared to those from Asian patients, the latter being largely resistant to BET inhibition. As BET inhibitors are entering clinical trials these findings provide the first starting point for future therapies targeting gastric cancer.


Subject(s)
Azepines/pharmacology , Cell Proliferation/drug effects , Isoxazoles/pharmacology , Nuclear Proteins/antagonists & inhibitors , Transcription Factors/antagonists & inhibitors , Triazoles/pharmacology , Apoptosis/drug effects , Apoptosis/genetics , Asian People , Azepines/chemistry , Brazil , Cell Cycle Proteins , Cell Line, Tumor , Cell Proliferation/genetics , Gene Expression Profiling , HEK293 Cells , Humans , Isoxazoles/chemistry , Molecular Structure , Nuclear Proteins/genetics , Nuclear Proteins/metabolism , Proto-Oncogene Proteins c-myc/genetics , Proto-Oncogene Proteins c-myc/metabolism , Spheroids, Cellular/drug effects , Spheroids, Cellular/metabolism , Stomach Neoplasms/ethnology , Stomach Neoplasms/genetics , Stomach Neoplasms/metabolism , Transcription Factors/genetics , Transcription Factors/metabolism , Triazoles/chemistry
6.
J Urol ; 195(5): 1578-1585, 2016 May.
Article in English | MEDLINE | ID: mdl-26719027

ABSTRACT

PURPOSE: We determine the ability of percutaneous needle based optical coherence tomography to differentiate renal masses by using the attenuation coefficient (µOCT, mm(-1)) as a quantitative measure. MATERIALS AND METHODS: Percutaneous needle based optical coherence tomography of the kidney was performed in patients presenting with a solid renal mass. A pathology specimen was acquired in the form of biopsies and/or a resection specimen. Optical coherence tomography results of 40 patients were correlated to pathology results of the resected specimens in order to derive µOCT values corresponding with oncocytoma and renal cell carcinoma, and with the 3 main subgroups of renal cell carcinoma. The sensitivity and specificity of optical coherence tomography in differentiating between oncocytoma and renal cell carcinoma were assessed through ROC analysis. RESULTS: The median µOCT of oncocytoma (3.38 mm(-1)) was significantly lower (p=0.043) than the median µOCT of renal cell carcinoma (4.37 mm(-1)). ROC analysis showed a µOCT cutoff value of greater than 3.8 mm(-1) to yield a sensitivity, specificity, positive predictive value and negative predictive value of 86%, 75%, 97% and 37%, respectively, to differentiate between oncocytoma and renal cell carcinoma. The area under the ROC curve was 0.81. Median µOCT was significantly lower for oncocytoma vs clear cell renal cell carcinoma (3.38 vs 4.36 mm(-1), p=0.049) and for oncocytoma vs papillary renal cell carcinoma (3.38 vs 4.79 mm(-1), p=0.027). CONCLUSIONS: We demonstrated that the µOCT is significantly higher in renal cell carcinoma vs oncocytoma, with ROC analysis showing promising results for their differentiation. This demonstrates the potential of percutaneous needle based optical coherence tomography to help in the differentiation of renal masses, thus warranting ongoing research.


Subject(s)
Carcinoma, Renal Cell/diagnosis , Kidney Neoplasms/diagnosis , Kidney/pathology , Needles , Tomography, Optical Coherence/instrumentation , Adult , Aged , Aged, 80 and over , Diagnosis, Differential , Female , Follow-Up Studies , Humans , Male , Middle Aged , Neoplasm Staging/methods , Pilot Projects , ROC Curve
7.
J Vasc Interv Radiol ; 27(3): 433-43, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26703782

ABSTRACT

PURPOSE: Irreversible electroporation (IRE) uses high-voltage electric fields to achieve cell death. Although the mechanism of IRE is mainly designated as nonthermal, development of secondary Joule heating is inevitable. The study purpose was to gain understanding of temperature development and distribution during IRE. MATERIALS AND METHODS: IRE was performed in a transparent polyacrylamide gel resembling soft tissue. Mechanical effects, changes in temperature gradient, and absolute temperature changes were measured with three different optical techniques (high-speed, color Schlieren, and infrared imaging) to investigate the effect on temperature of variations in voltage, pulse length, active tip length (ATL), interelectrode distance, electrode configuration (parallel, convergent, and divergent), and sequential pulsing (pulse delivery interrupted by breaks). The total delivered energy was calculated. RESULTS: A temperature gradient, starting at the tips of both electrodes and expanding toward each other, developed immediately with pulse delivery. Temperatures increased with increasing voltage (by 2.5°C-40.4°C), pulse length (by 5.3°C-9.8°C), ATL (by 5.9°C-17.6°C), and interelectrode distance (by 7.6°C-21.5°C), in accordance with higher energy delivery. Nonparallel electrode placement resulted in heterogeneous temperature distribution with the peak temperature focused in the area with the shortest interelectrode distance. Sequential pulse delivery significantly reduced the temperature increase compared with continuous pulsing (4.3°C vs 11.7°C). CONCLUSIONS: Voltage, pulse length, interelectrode distance, ATL, and electrode configuration each have a strong effect on temperature development and distribution during IRE. Sequential pulsing reduces the extent and volume of thermal distribution and may prove beneficial with respect to procedural safety.


Subject(s)
Ablation Techniques , Acrylic Resins/chemistry , Electroporation , Hot Temperature , Electric Conductivity , Energy Transfer , Gases , Models, Anatomic , Thermography , Time Factors , Video Recording
8.
Medchemcomm ; 7(12): 2246-2264, 2016 Dec 07.
Article in English | MEDLINE | ID: mdl-29170712

ABSTRACT

In the last five years, the development of inhibitors of bromodomains has emerged as an area of intensive worldwide research. Emerging evidence has implicated a number of non-BET bromodomains in the onset and progression of diseases such as cancer, HIV infection and inflammation. The development and use of small molecule chemical probes has been fundamental to pre-clinical evaluation of bromodomains as targets. Recent efforts are described highlighting the development of potent, selective and cell active non-BET bromodomain inhibitors and their therapeutic potential. Over half of typical bromodomains now have reported ligands, but those with atypical binding site residues remain resistant to chemical probe discovery efforts.

9.
BMC Cancer ; 15: 165, 2015 Mar 22.
Article in English | MEDLINE | ID: mdl-25886058

ABSTRACT

BACKGROUND: Electroporation is a novel treatment technique utilizing electric pulses, traveling between two or more electrodes, to ablate targeted tissue. The first in human studies have proven the safety of IRE for the ablation of renal masses. However the efficacy of IRE through histopathological examination of an ablated renal tumour has not yet been studied. Before progressing to a long-term IRE follow-up study it is vital to have pathological confirmation of the efficacy of the technique. Furthermore, follow-up after IRE ablation requires a validated imaging modality. The primary objectives of this study are the safety and the efficacy of IRE ablation of renal masses. The secondary objectives are the efficacy of MRI and CEUS in the imaging of ablation result. METHODS/DESIGN: 10 patients, age ≥ 18 years, presenting with a solid enhancing mass, who are candidates for radical nephrectomy will undergo IRE ablation 4 weeks prior to radical nephrectomy. MRI and CEUS imaging will be performed at baseline, one week and four weeks post IRE. After radical nephrectomy, pathological examination will be performed to evaluate IRE ablation success. DISCUSSION: The only way to truly assess short-term (4 weeks) ablation success is by histopathology of a resection specimen. In our opinion this trial will provide essential knowledge on the safety and efficacy of IRE of renal masses, guiding future research of this promising ablative technique. TRIAL REGISTRATION: Clinicaltrials.gov registration number NCT02298608 . Dutch Central Committee on Research Involving Human Subjects registration number NL44785.018.13.


Subject(s)
Catheter Ablation/methods , Electroporation/methods , Kidney Neoplasms/diagnosis , Kidney Neoplasms/therapy , Catheter Ablation/instrumentation , Electroporation/instrumentation , Humans , Prospective Studies , Treatment Outcome
10.
Angew Chem Int Ed Engl ; 54(21): 6217-21, 2015 May 18.
Article in English | MEDLINE | ID: mdl-25864491

ABSTRACT

The bromodomain-containing proteins BRD9 and BRD7 are part of the human SWI/SNF chromatin-remodeling complexes BAF and PBAF. To date, no selective inhibitor for BRD7/9 has been reported despite its potential value as a biological tool or as a lead for future therapeutics. The quinolone-fused lactam LP99 is now reported as the first potent and selective inhibitor of the BRD7 and BRD9 bromodomains. Development of LP99 from a fragment hit was expedited through balancing structure-based inhibitor design and biophysical characterization against tractable chemical synthesis: Complexity-building nitro-Mannich/lactamization cascade processes allowed for early structure-activity relationship studies whereas an enantioselective organocatalytic nitro-Mannich reaction enabled the synthesis of the lead scaffold in enantioenriched form and on scale. This epigenetic probe was shown to inhibit the association of BRD7 and BRD9 to acetylated histones in vitro and in cells. Moreover, LP99 was used to demonstrate that BRD7/9 plays a role in regulating pro-inflammatory cytokine secretion.


Subject(s)
Chromosomal Proteins, Non-Histone/antagonists & inhibitors , Drug Discovery , Lactams/chemistry , Lactams/pharmacology , Transcription Factors/antagonists & inhibitors , Chromosomal Proteins, Non-Histone/chemistry , Chromosomal Proteins, Non-Histone/metabolism , Humans , Models, Molecular , Transcription Factors/chemistry , Transcription Factors/metabolism
11.
Urol Oncol ; 33(4): 168.e1-7, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25557146

ABSTRACT

OBJECTIVE: Although tissue ablation by irreversible electroporation (IRE) has been characterized as nonthermal, the application of frequent repetitive high-intensity electric pulses has the potential of substantially heating the targeted tissue and causing thermal damage. This study evaluates the risk of possible thermal damage by measuring temperature development and distribution during IRE of porcine kidney tissue. METHODS: The animal procedures were conducted following an approved Institutional Animal Ethics Committee protocol. IRE ablation was performed in 8 porcine kidneys. Of them, 4 kidneys were treated with a 3-needle configuration and the remaining 4 with a 4-needle configuration. All IRE ablations consisted of 70 pulses with a length 90 µs. The pulse frequency was set at 90 pulses/min, and the pulse intensity at 1,500 V/cm with a spacing of 15 mm between the needles. The temperature was measured internally using 4 fiber-optic temperature probes and at the surface using a thermal camera. RESULTS: For the 3-needle configuration, a peak temperature of 57°C (mean = 49 ± 10°C, n = 3) was measured in the core of the ablation zone and 40°C (mean = 36 ± 3°C, n = 3) at 1cm outside of the ablation zone, from a baseline temperature of 33 ± 1°C. For the 4-needle configuration, a peak temperature of 79°C (mean = 62 ± 16°C, n = 3) was measured in the core of the ablation zone and 42°C (mean = 39 ± 3°C, n = 3) at 1cm outside of the ablation zone, from a baseline of 35 ± 1°C. The thermal camera recorded the peak surface temperatures in the center of the ablation zone, reaching 31°C and 35°C for the 3- and 4-needle configuration IRE (baseline 22°C). CONCLUSIONS: The application of repetitive high-intensity electric pulses during IRE ablation in porcine kidney causes a lethal rise in temperature within the ablation zone. Temperature monitoring should be considered when performing IRE ablation near vital structures.


Subject(s)
Electrochemotherapy/adverse effects , Kidney , Animals , Electroporation/methods , Models, Animal , Sus scrofa , Temperature
12.
Angew Chem Weinheim Bergstr Ger ; 127(21): 6315-6319, 2015 May 18.
Article in English | MEDLINE | ID: mdl-27346896

ABSTRACT

The bromodomain-containing proteins BRD9 and BRD7 are part of the human SWI/SNF chromatin-remodeling complexes BAF and PBAF. To date, no selective inhibitor for BRD7/9 has been reported despite its potential value as a biological tool or as a lead for future therapeutics. The quinolone-fused lactam LP99 is now reported as the first potent and selective inhibitor of the BRD7 and BRD9 bromodomains. Development of LP99 from a fragment hit was expedited through balancing structure-based inhibitor design and biophysical characterization against tractable chemical synthesis: Complexity-building nitro-Mannich/lactamization cascade processes allowed for early structure-activity relationship studies whereas an enantioselective organocatalytic nitro-Mannich reaction enabled the synthesis of the lead scaffold in enantioenriched form and on scale. This epigenetic probe was shown to inhibit the association of BRD7 and BRD9 to acetylated histones in vitro and in cells. Moreover, LP99 was used to demonstrate that BRD7/9 plays a role in regulating pro-inflammatory cytokine secretion.

13.
Prostate ; 75(3): 332-5, 2015 Feb 15.
Article in English | MEDLINE | ID: mdl-25327875

ABSTRACT

BACKGROUND: Irreversible electroporation (IRE) is (virtually) always called non-thermal despite many reports showing that significant Joule heating occurs. Our first aim is to validate with mathematical simulations that IRE as currently practiced has a non-negligible thermal response. Our second aim is to present a method that allows simple temperature estimation to aid IRE treatment planning. METHODS: We derived an approximate analytical solution of the bio-heat equation for multiple 2-needle IRE pulses in an electrically conducting medium, with and without a blood vessel, and incorporated published observations that an electric pulse increases the medium's electric conductance. RESULTS: IRE simulation in prostate-resembling tissue shows thermal lesions with 67-92°C temperatures, which match the positions of the coagulative necrotic lesions seen in an experimental study. Simulation of IRE around a blood vessel when blood flow removes the heated blood between pulses confirms clinical observations that the perivascular tissue is thermally injured without affecting vascular patency. CONCLUSIONS: The demonstration that significant Joule heating surrounds current multiple-pulsed IRE practice may contribute to future in-depth discussions on this thermal issue. This is an important subject because it has long been under-exposed in literature. Its awareness pleads for preventing IRE from calling "non-thermal" in future publications, in order to provide IRE-users with the most accurate information possible. The prospect of thermal treatment planning as outlined in this paper likely aids to the important further successful dissemination of IRE in interventional medicine. Prostate 75:332-335, 2015. © 2014 The Authors. The Prostate Published by Wiley Periodicals, Inc.


Subject(s)
Electroporation/methods , Hot Temperature , Prostatic Neoplasms/therapy , Electric Conductivity , Humans , Male , Models, Biological
14.
Org Biomol Chem ; 10(9): 1725-9, 2012 Mar 07.
Article in English | MEDLINE | ID: mdl-22246312

ABSTRACT

Malonganenone B (1) exhibits an unusual H-D exchange of a formyl proton when in deuteric-NMR solvents. Synthetic and kinetic investigations were made to probe the mechanism of this exchange, which appears to occur via an uncommon and transient amine-amide NHC intermediate.


Subject(s)
Deuterium/chemistry , Diterpenes/chemistry , Hydrogen/chemistry , Imidazoles/chemistry , Kinetics , Methane/analogs & derivatives , Methane/chemistry , Molecular Structure
15.
Biol Chem ; 392(5): 431-8, 2011 May.
Article in English | MEDLINE | ID: mdl-21426241

ABSTRACT

Plasmodium falciparum heat shock protein 70 (PfHsp70-1) is thought to play an essential role in parasite survival and virulence in the human host, making it a potential antimalarial drug target. A malate dehydrogenase based aggregation suppression assay was adapted for the screening of small molecule modulators of Hsp70. A number of small molecules of natural (marine prenylated alkaloids and terrestrial plant naphthoquinones) and related synthetic origin were screened for their effects on the protein aggregation suppression activity of purified recombinant PfHsp70-1. Five compounds (malonganenone A-C, lapachol and bromo-ß-lapachona) were found to inhibit the chaperone activity of PfHsp70-1 in a concentration dependent manner, with lapachol preferentially inhibiting PfHsp70-1 compared to another control Hsp70. Using growth inhibition assays on P. falciparum infected erythrocytes, all of the compounds, except for malonganenone B, were found to inhibit parasite growth with IC(50) values in the low micromolar range. Overall, this study has identified two novel classes of small molecule inhibitors of PfHsp70-1, one representing a new class of antiplasmodial compounds (malonganenones). In addition to demonstrating the validity of PfHsp70-1 as a possible drug target, the compounds reported in this study will be potentially useful as molecular probes for fundamental studies on Hsp70 chaperone function.


Subject(s)
Antimalarials/pharmacology , HSP72 Heat-Shock Proteins/metabolism , Plasmodium falciparum/metabolism , Alkaloids/pharmacology , HSP72 Heat-Shock Proteins/drug effects , Inhibitory Concentration 50 , Naphthoquinones/pharmacology , Plasmodium falciparum/drug effects
16.
J Med Primatol ; 27(6): 273-7, 1998 Dec.
Article in English | MEDLINE | ID: mdl-10203006

ABSTRACT

A 31-year-old male and a 31-year-old female rhesus monkey developed clinical signs consistent with hyperthryoidism. These included a ravenous appetite, hyperactivity, and accentuated ratchet movement and hand tremors while performing fine motor tasks. Bilaterally enlarged thyroid glands were palpated in both monkeys. A unique clinical finding of the female as the hypertrophic cardiomyopathy. The T3 and T4 levels in the male rhesus were 3.79 ng/ml and 28.20 microg/dl, respectively. T3 and T4 levels in the female were 4.33 ng/ml and 22.2 microg/dl, respectively. A biopsy of the enlarged thyroids demonstrated a typical multinodular goiter with cystic hyperplasia. The female rhesus was successfully treated with methimazole, but the hypertrophic cardiomyopathy did not resolve. The relationship between erythrocytosis and T4 levels common to humans and cats is also evident in the rhesus monkey.


Subject(s)
Hyperthyroidism/veterinary , Macaca mulatta , Monkey Diseases/physiopathology , Aging/pathology , Animals , Female , Hunger , Hyperthyroidism/complications , Hyperthyroidism/physiopathology , Male , Methimazole/therapeutic use , Movement , Polycythemia/complications , Thyroid Gland/pathology , Thyroxine/blood , Time Factors , Triiodothyronine/blood
17.
J Med Primatol ; 24(4): 231-5, 1995 Dec.
Article in English | MEDLINE | ID: mdl-8750498

ABSTRACT

This report documents asymptomatic infections of Mycobacterium kansasii in four of five tuberculin positive squirrel monkeys (Saimiri sciureus sciureus). The mycobacterial DNA amplified by polymerase chain reaction (PCR) from a bronchial lymph node had no affinity for the species specific probes of M. tuberculosis, M. avium, and M. intracellulare, thus allowing the presumptive diagnosis of an atypical mycobacterial infection. Infection by Mycobacterium kansasii was confirmed by culture of bronchial lymph nodes from three monkeys. The source of the infection was never identified.


Subject(s)
Mycobacterium Infections/veterinary , Mycobacterium/isolation & purification , Primate Diseases , Animals , DNA, Bacterial/analysis , Humans , Lymph Nodes/microbiology , Lymph Nodes/pathology , Male , Mycobacterium Infections/diagnosis , Mycobacterium Infections/pathology , Polymerase Chain Reaction , Saimiri , Sensitivity and Specificity , Tuberculin Test
19.
Infect Immun ; 49(3): 498-504, 1985 Sep.
Article in English | MEDLINE | ID: mdl-4030090

ABSTRACT

Antigens were extracted from a virulent isolate of Pasteurella multocida (serotype 3, 12, 15:D) with potassium thiocyanate, and a vaccine was prepared. Pasteurella-free rabbits were vaccinated intranasally and intraconjuctivally twice with a 2-week interval and challenged intranasally with the homologous P. multocida serotype 2 weeks after the second vaccination. The vaccinated rabbits produced serum immunoglobulin G and nasal mucosal immunoglobulin A against P. multocida. The vaccine protected the challenged rabbits against clinical disease and death; however, otitis media was not prevented, and microscopic inflammatory lesions were occasionally noted in the lungs and nasal turbinates. In contrast, nonvaccinated, challenged rabbits became febrile, dyspnic, depressed, and anorectic, and five of six died within 4 days of challenge with severe lesions including pneumonia, pleuritis, otitis media, and bacteremia. The vaccine prevented death and colonization of challenge organisms in the blood and lung, but did not prevent colonization of the middle ear. The vaccine alone did not cause clinical disease or gross lesions, but did produce microscopic pulmonary inflammatory lesions.


Subject(s)
Bacterial Vaccines/immunology , Pasteurella Infections/prevention & control , Pasteurella/immunology , Animals , Antibodies, Bacterial/analysis , Bacterial Vaccines/toxicity , Female , Immunoglobulin A/analysis , Immunoglobulin G/analysis , Pasteurella Infections/immunology , Pasteurella Infections/pathology , Rabbits , Thiocyanates , Vaccination
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