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1.
Osteoarthritis Cartilage ; 25(10): 1708-1718, 2017 10.
Article in English | MEDLINE | ID: mdl-28668542

ABSTRACT

OBJECTIVE: Natural killer (NK) cells have been involved in the pathology of different inflammatory and autoimmune disorders. Inflammation is an important regulator of osteoarthritis (OA), but the molecular and cellular mechanisms regulating this process are not well defined. DESIGN: To understand the role of NK cells in OA, we have compared the phenotype (CD56 subsets and perforin and granzyme expression) and cytotoxic function of NK cells in peripheral blood and synovial fluid from patients with OA undergoing total knee arthroplasty. RESULTS: In contrast to peripheral blood lymphocytes (PBLs), the majority of NK cells from the synovial fluid were CD56brightCD16(-) cells. As expected the expression of the cytolytic mediators perforin and granzyme B in CD56brightCD16(-) cells was low and correlated with a poor cytotoxic potential against K562 sensitive target cells. Surprisingly, this low cytotoxic NK cell subset expressed high levels of granzyme A (a protease recently characterized as a key modulator of inflammation in mouse models) in synovial fluid but not in peripheral blood. The presence of the CD56(+)brightCD16(-) cells expressing granzyme A correlated with increased levels of pro-inflammatory cytokines in synovial fluid from OA patients. CONCLUSION: Our results indicate that NK cells from the synovium of patients with OA, which present an immunoregulatory non-cytotoxic phenotype, show different phenotype comparing with NK cells from peripheral blood, especially expressing granzyme A, a pro-inflammatory molecule which may contribute to the establishment of chronic articular inflammation in this type of patients.


Subject(s)
Granzymes/metabolism , Killer Cells, Natural/metabolism , Osteoarthritis, Knee/immunology , Synovial Fluid/immunology , Aged , Arthroplasty, Replacement, Knee , CD56 Antigen/metabolism , Cytokines/biosynthesis , Cytotoxicity, Immunologic , Female , Humans , Immunophenotyping , Inflammation Mediators/metabolism , Lymphocyte Subsets/immunology , Male , Middle Aged , Osteoarthritis, Knee/surgery , Perforin/metabolism , Receptors, IgG/metabolism
2.
Curr Mol Med ; 17(1): 13-23, 2017.
Article in English | MEDLINE | ID: mdl-28231753

ABSTRACT

More than thirty years have passed since the discovery of the prion protein (PrP) and its causative role in transmissible spongiform encephalopathy. Since a combination of both gain- and loss-of-function mechanisms may underlay prion pathogenesis, understanding the physiological role of PrP may give important clues about disease mechanisms. Historically, the primary strategy for prion research has involved the use of human tissue, cell cultures and mammalian animal models. Nevertheless, experimental difficulties of in vivo studies and controversial observations obtained in these systems have stimulated the search for alternative animal models. PrPC is highly conserved in mammals, and PrPC-related orthologs are expressed in zebrafish, a vertebrate model organism suitable to study the mechanisms associated with human diseases. Invertebrate models, as they do not express PrPC have served to investigate the neurotoxic mechanisms of mammalian PrP. Here we overview most recent advances in the study of PrP function in normal and pathogenic conditions based on non-mammalian studies, highlighting the contribution of zebrafish, fly and worms to our current understanding of PrP biology.


Subject(s)
Disease Models, Animal , Prion Diseases/etiology , Prion Diseases/metabolism , Prions/genetics , Prions/metabolism , Animals , Caenorhabditis elegans , Drosophila , Humans , Prion Diseases/pathology , Prions/chemistry , Structure-Activity Relationship , Zebrafish
3.
Sci Rep ; 6: 31819, 2016 08 22.
Article in English | MEDLINE | ID: mdl-27545976

ABSTRACT

The chikungunya virus (CHIKV) has become a substantial global health threat due to its massive re-emergence, the considerable disease burden and the lack of vaccines or therapeutics. We discovered a novel class of small molecules ([1,2,3]triazolo[4,5-d]pyrimidin-7(6H)-ones) with potent in vitro activity against CHIKV isolates from different geographical regions. Drug-resistant variants were selected and these carried a P34S substitution in non-structural protein 1 (nsP1), the main enzyme involved in alphavirus RNA capping. Biochemical assays using nsP1 of the related Venezuelan equine encephalitis virus revealed that the compounds specifically inhibit the guanylylation of nsP1. This is, to the best of our knowledge, the first report demonstrating that the alphavirus capping machinery is an excellent antiviral drug target. Considering the lack of options to treat CHIKV infections, this series of compounds with their unique (alphavirus-specific) target offers promise for the development of therapy for CHIKV infections.


Subject(s)
Antiviral Agents/pharmacology , Chikungunya virus/genetics , Pyrimidinones/pharmacology , Viral Nonstructural Proteins/genetics , Amino Acid Substitution , Animals , Antiviral Agents/chemistry , Chikungunya virus/drug effects , Chikungunya virus/metabolism , Chlorocebus aethiops , Drug Resistance, Viral/drug effects , Encephalomyelitis, Equine/virology , Horses , Molecular Structure , Pyrimidinones/chemistry , Small Molecule Libraries/chemistry , Small Molecule Libraries/pharmacology , Vero Cells , Viral Nonstructural Proteins/antagonists & inhibitors , Viral Nonstructural Proteins/metabolism
4.
Diabetes Res Clin Pract ; 117: 32-8, 2016 Jul.
Article in English | MEDLINE | ID: mdl-27329020

ABSTRACT

INTRODUCTION: Muscle mass and function are among the most relevant factors that contribute to an optimal quality of life, and are strong predictors of mortality in the elderly. Loss of lean tissues and deterioration of muscle function have been described as one of the many complications of type 2 diabetes mellitus (DM2), but most studies do not isolate age as an intervening factor. AIM: To study whether adult DM2 patients up to 60years of age have decreased muscle mass and function compared with healthy non-diabetic (ND) subjects of similar age. METHODOLOGY: Appendicular fat-free mass (ApFFM) by dual X-ray absorptiometry (DEXA), handgrip strength (HS), quadriceps strength (QS), 12 min walking capacity (12MW) and the Timed Up and Go test (TUG) were measured in 100 DM2 patients and 39 ND controls. Muscle quality, or the ratio between lean mass and muscle strength of upper and lower limbs, and the functional limitations associated with pain and stiffness assessed according to the Western Ontario and McMaster Universities Arthrosis Index (WOMAC) were also recorded. Specific tests were performed to rule out microvascular diabetic complications (retinal and peripheral nerves), metabolic control, kidney function and vitamin D status and examine their association with ApFFM and function. RESULTS: ApFFM was significantly higher among DM2 female patients and lower among diabetic men. However opposite results were obtained when individual values were corrected for body mass index (BMI), specifically among women, who were more likely to be obese. As for muscle strength and global functionality tests, significantly better performances in TUG, 12MW, QS and HS were observed among ND subjects of both sexes. These differences prevailed even after excluding diabetic patients with microvascular complications as well as those with more than 10years of diabetes. Muscle quality was also significantly better among ND women. Higher scores of pain and stiffness in the WOMAC scale correlated with 12MW and TUG in both groups but did not correlate with ApFFM. CONCLUSIONS: We found a clear deterioration of lean mass and muscle functions among adult DM2 patients of up to 60years old, independent of length of disease, metabolic control, vitamin D status and presence of microvascular complications and pain.


Subject(s)
Diabetes Complications/etiology , Diabetes Mellitus, Type 2/complications , Hand Strength/physiology , Muscle Strength/physiology , Quality of Life , Sarcopenia/etiology , Absorptiometry, Photon , Adult , Case-Control Studies , Diabetes Complications/diagnosis , Diabetes Mellitus, Type 2/physiopathology , Female , Humans , Male , Middle Aged , Ontario , Sarcopenia/diagnosis , Walking
5.
Vet Rec ; 173(24): 608, 2013 Dec 21.
Article in English | MEDLINE | ID: mdl-24158326

ABSTRACT

To compare different volumes of injectate using electrostimulator (ES)-guided and blind brachial plexus blockade (BPB) techniques in dogs. Prospective, randomised, blinded study. Fifty-eight healthy adult purpose-bred beagle dogs. Animals were randomised into 4 groups based on the volume of methylene blue 0.1 per cent administered for BPB, three using ES technique: E1 (0.2 ml/kg, n=22), E2 (0.6 ml/kg, n=22), and E3 (1.0 ml/kg, n=14), and one using blinded technique B4 (1.0 ml/kg, n=14). After euthanasia, the axillary region was dissected and nerves identified by a blinded evaluator. Success was defined as 3/4 nerves stained, or presence of dye in the tissue immediately surrounding the plexus. There were no significant differences between groups when total nerve count, adjacent staining, success rate (92.8-100 per cent), or rate of haematoma were evaluated. The musculocutaneous nerve was significantly more targeted in B4 than E1 and E2, but not E3. Electrostimulator-guided BPB using lower volumes of injectate had similar success rate as the blinded technique using higher volume, thus, lower volumes can be used without compromising success. When an ES is not available, the blind technique with 1 ml/kg is also acceptable. However, when performing an ES-guided BPB, volumes as low as 0.2 ml/kg can be used. As volume is increased, the musculocutaneous nerve becomes more likely to be targeted.


Subject(s)
Anesthesia, Conduction/veterinary , Brachial Plexus/surgery , Methylene Blue/administration & dosage , Nerve Block/veterinary , Anesthesia, Conduction/methods , Animals , Dogs , Double-Blind Method , Electric Stimulation , Nerve Block/methods , Prospective Studies
7.
Rev. esp. anestesiol. reanim ; 58(7): 337-344, sept.-oct. 2011. tab
Article in Spanish | IBECS | ID: ibc-91095

ABSTRACT

Objetivos: Presentamos una revisión sistemática de los ensayos clínicos que tuvieron como objetivo valorar la eficacia de la administración de anestésico local con catéter en la incisión quirúrgica, en pacientes sometidos a cirugía abdominal. Método: Selección de los estudios siguiendo los criterios de Jadad. Las variables evaluadas en cada estudio fueron: tipo de intervención y de incisión, tipo, dosis y concentración del anestésico local, sitio de ubicación o localización del catéter, analgesia de rescate, consumo de opioides y la aparición de efectos adversos. Resultados: Se han incluido 15 ensayos con puntuación media de Jadad de 4,6 que incluyen 1.139 pacientes agrupados según la ubicación del catéter: subfascial (6 estudios), subcutánea (8 estudios) y en ambas (1 estudio), y 6 estudios adicionales que están en fase de realización registrados en ClinicalTrials.gov. Discusión: La analgesia incisional es una técnica segura, cuya eficacia se ha observado en cesáreas e histerectomías realizadas mediante incisiones de Pfannenstiel. Los resultados son contradictorios en otras técnicas quirúrgicas. Faltan estudios para conocer la localización óptima del catéter así como la concentración y volumen adecuado (AU)


Objectives: We present a systematic review of clinical trials to evaluate the efficacy of infusing local anesthetic through a catheter placed in the abdominal surgical wound. Methods: The Jadad (Oxford) scoring system was used to select trials. The variables considered in relation to each trial selected were as follows: type of intervention and incision; type, dose, and concentration of local anesthetic; site where the catheter was placed; rescue analgesia required; opioid use; and incidence of adverse events. Results: Fifteen clinical trials with a mean Jadad score of 4.6 were selected. The 1139 patients enrolled in the trials were grouped according to catheter placement: subfascial (6 trials), subcutaneous (8 trials), and both (1 trial). Six additional unpublished trials registered at ClinicalTrials.gov were also located. Conclusions: Surgical wound analgesia is a safe technique whose effectiveness has been observed in cesarean sections and hysterectomies performed with Pfannenstiel incisions. Outcomes for other types of surgery are inconsistent. There is a lack of studies of the optimal site for catheter placement as well as of adequate anesthetic concentration and volume (AU)


Subject(s)
Humans , Female , Anesthesia, Local/instrumentation , Anesthesia, Local/methods , Analgesics, Opioid/adverse effects , /instrumentation , /methods , Catheters , Cesarean Section/methods , Hysterectomy/methods
8.
Rev Esp Anestesiol Reanim ; 58(6): 337-44, 2011.
Article in Spanish | MEDLINE | ID: mdl-21797083

ABSTRACT

OBJECTIVES: We present a systematic review of clinical trials to evaluate the efficacy of infusing local anesthetic through a catheter placed in the abdominal surgical wound. METHODS: The Jadad (Oxford) scoring system was used to select trials. The variables considered in relation to each trial selected were as follows: type of intervention and incision; type, dose, and concentration of local anesthetic; site where the catheter was placed; rescue analgesia required; opioid use; and incidence of adverse events. RESULTS: Fifteen clinical trials with a mean Jadad score of 4.6 were selected. The 1139 patients enrolled in the trials were grouped according to catheter placement: subfascial (6 trials), subcutaneous (8 trials), and both (1 trial). Six additional unpublished trials registered at ClinicalTrials.gov were also located. CONCLUSIONS: Surgical wound analgesia is a safe technique whose effectiveness has been observed in cesarean sections and hysterectomies performed with Pfannenstiel incisions. Outcomes for other types of surgery are inconsistent. There is a lack of studies of the optimal site for catheter placement as well as of adequate anesthetic concentration and volume.


Subject(s)
Abdomen/surgery , Analgesia , Anesthetics, Local/administration & dosage , Pain, Postoperative/prevention & control , Analgesia/methods , Humans , Infusions, Intralesional
9.
Rev. esp. anestesiol. reanim ; 58(6): 337-344, jun.-jul. 2011. tab
Article in Spanish | IBECS | ID: ibc-89948

ABSTRACT

Objetivos: Presentamos una revisión sistemática de los ensayos clínicos que tuvieron como objetivo valorar la eficacia de la administración de anestésico local con catéter en la incisión quirúrgica, en pacientes sometidos a cirugía abdominal. Método: Selección de los estudios siguiendo los criterios de Jadad. Las variables evaluadas en cada estudio fueron: tipo de intervención y de incisión, tipo, dosis y concentración del anestésico local, sitio de ubicación o localización del catéter, analgesia de rescate, consumo de opioides y la aparición de efectos adversos. Resultados: Se han incluido 15 ensayos con puntuación media de Jadad de 4,6 que incluyen 1.139 pacientes agrupados según la ubicación del catéter: subfascial (6 estudios), subcutánea (8 estudios) y en ambas (1 estudio), y 6 estudios adicionales que están en fase de realización registrados en ClinicalTrials.gov. Discusión: La analgesia incisional es una técnica segura, cuya eficacia se ha observado en cesáreas e histerectomías realizadas mediante incisiones de Pfannenstiel. Los resultados son contradictorios en otras técnicas quirúrgicas. Faltan estudios para conocer la localización óptima del catéter así como la concentración y volumen adecuado(AU)


Objectives: We present a systematic review of clinical trials to evaluate the efficacy of infusing local anesthetic through a catheter placed in the abdominal surgical wound. Methods: The Jadad (Oxford) scoring system was used to select trials. The variables considered in relation to each trial selected were as follows: type of intervention and incision; type, dose, and concentration of local anesthetic; site where the catheter was placed; rescue analgesia required; opioid use; and incidence of adverse events. Results: Fifteen clinical trials with a mean Jadad score of 4.6 were selected. The 1139 patients enrolled in the trials were grouped according to catheter placement: subfascial (6 trials), subcutaneous (8 trials), and both (1 trial). Six additional unpublished trials registered at ClinicalTrials.gov were also located. Conclusions: Surgical wound analgesia is a safe technique whose effectiveness has been observed in cesarean sections and hysterectomies performed with Pfannenstiel incisions. Outcomes for other types of surgery are inconsistent. There is a lack of studies of the optimal site for catheter placement as well as of adequate anesthetic concentration and volume(AU)


Subject(s)
Humans , Male , Female , Anesthesia, Local/methods , Anesthesia, Local , Anesthetics, Local/administration & dosage , Efficacy/methods , Treatment Outcome , Evaluation of the Efficacy-Effectiveness of Interventions , /instrumentation , Analgesics, Opioid/adverse effects , Anesthesia, Local/trends , Abdomen/surgery , /instrumentation , /methods , Cesarean Section/instrumentation , Hysterectomy
10.
Technol Cancer Res Treat ; 10(1): 73-83, 2011 Feb.
Article in English | MEDLINE | ID: mdl-21214290

ABSTRACT

Non-thermal irreversible electroporation (N-TIRE) has shown promise as an ablative therapy for a variety of soft-tissue neoplasms. Here we describe the therapeutic planning aspects and first clinical application of N-TIRE for the treatment of an inoperable, spontaneous malignant intracranial glioma in a canine patient. The N-TIRE ablation was performed safely, effectively reduced the tumor volume and associated intracranial hypertension, and provided sufficient improvement in neurological function of the patient to safely undergo adjunctive fractionated radiotherapy (RT) according to current standards of care. Complete remission was achieved based on serial magnetic resonance imaging examinations of the brain, although progressive radiation encephalopathy resulted in the death of the dog 149 days after N-TIRE therapy. The length of survival of this patient was comparable to dogs with intracranial tumors treated via standard excisional surgery and adjunctive fractionated external beam RT. Our results illustrate the potential benefits of N-TIRE for in vivo ablation of undesirable brain tissue, especially when traditional methods of cytoreductive surgery are not possible or ideal, and highlight the potential radiosensitizing effects of N-TIRE on the brain.


Subject(s)
Ablation Techniques/veterinary , Brain Neoplasms/veterinary , Dog Diseases/therapy , Electroporation/veterinary , Glioma/veterinary , Ablation Techniques/methods , Animals , Brain Diseases/etiology , Brain Diseases/mortality , Brain Diseases/veterinary , Brain Neoplasms/radiotherapy , Brain Neoplasms/therapy , Combined Modality Therapy/veterinary , Dog Diseases/radiotherapy , Dogs , Dose Fractionation, Radiation , Electroporation/methods , Glioma/radiotherapy , Glioma/therapy , Male , Prognosis , Radiotherapy Planning, Computer-Assisted/veterinary , Radiotherapy, Adjuvant/veterinary
11.
Ecotoxicol Environ Saf ; 68(2): 286-92, 2007 Oct.
Article in English | MEDLINE | ID: mdl-17196654

ABSTRACT

Paraquat is still a widely used herbicide in several countries. Its toxic action on plants occurs through a one-electron reduction interfering with the photosynthesis process. By a similar reaction, the herbicide may induce peroxidation processes in non-target animal species. Furthermore, paraquat may interfere with the cellular transport of polyamines. The aim of this work was to investigate some aspects related to paraquat-induction of oxidative stress (lipoperoxidation, enzymatic activities of catalase and superoxide dismutase) and also the levels of polyamines (putrescine, spermidine and spermine) in two species of freshwater invertebrates, the oligochaete Lumbriculus variegatus and the gastropod Biomphalaria glabrata. The results showed that both organisms elicited differential responses. In addition, the data suggested that polyamines may play an important role against lipoperoxidation processes.


Subject(s)
Biomphalaria/drug effects , Herbicides/toxicity , Oligochaeta/drug effects , Oxidative Stress/drug effects , Paraquat/toxicity , Polyamines/metabolism , Animals , Biomphalaria/enzymology , Biomphalaria/metabolism , Catalase/metabolism , Fresh Water , Lipid Peroxidation/drug effects , Oligochaeta/enzymology , Oligochaeta/metabolism , Putrescine/metabolism , Spermidine/metabolism , Spermine/metabolism , Superoxide Dismutase/metabolism , Time Factors
12.
Environ Pollut ; 145(1): 238-44, 2007 Jan.
Article in English | MEDLINE | ID: mdl-16690183

ABSTRACT

The complex and variable composition of natural sediments makes it very difficult to predict the bioavailability and bioaccumulation of sediment-bound contaminants. Several approaches have been proposed to overcome this problem, including an experimental model using artificial particles with or without humic acids as a source of organic matter. For this work, we have applied this experimental model, and also a sample of a natural sediment, to investigate the uptake and bioaccumulation of 2,4-dichlorophenol (2,4-DCP) by Sphaerium corneum. Additionally, the particle-water partition coefficients (K(d)) were calculated. The results showed that the bioaccumulation of 2,4-DCP by clams did not depend solely on the levels of chemical dissolved, but also on the amount sorbed onto the particles and the characteristics and the strength of that binding. This study confirms the value of using artificial particles as a suitable experimental model for assessing the fate of sediment-bound contaminants.


Subject(s)
Bivalvia/metabolism , Chlorophenols/pharmacokinetics , Geologic Sediments , Humic Substances , Water Pollutants, Chemical/pharmacokinetics , Aluminum Silicates , Animals , Biological Availability , Clay , Fresh Water , Hydrogen-Ion Concentration , Models, Biological , Resins, Synthetic
13.
Environ Pollut ; 121(1): 115-22, 2003.
Article in English | MEDLINE | ID: mdl-12475068

ABSTRACT

Hydrophobic chemicals are known to associate with sediment particles including those from both suspended particulate matter and bottom deposits. The complex and variable composition of natural particles makes it very difficult therefore, to predict the bioavailability of sediment-bound contaminants. To overcome these problems we have previously devised a test system using artificial particles, with or without humic acids, for use as an experimental model of natural sediments. In the present work we have applied this experimental technique to investigate the bioavailability and bioaccumulation of pyrene by the freshwater fingernail clam Sphaerium corneum. The uptake and accumulation of pyrene in clams exposed to the chemical in the presence of a sample of natural sediment was also investigated. According to the results obtained, particle surface properties and organic matter content are the key factors for assessing the bioavailability and bioaccumulation of pyrene by clams.


Subject(s)
Bivalvia/chemistry , Pyrenes/analysis , Toxicity Tests/methods , Water Pollutants, Chemical/analysis , Absorption , Analysis of Variance , Animals , Biological Availability , Geologic Sediments , Humic Substances , Particle Size
14.
Environ Pollut ; 117(3): 523-30, 2002.
Article in English | MEDLINE | ID: mdl-11926182

ABSTRACT

Acute static bioassays were performed using three freshwater invertebrate species (the oligochaete Lumbriculus variegatus, the fingernail clam Sphaerium corneum and the larvae Chironomus riparius) exposed separately to a variety of 14C radiolabelled contaminants. The aim of this work was to investigate if the chemicals remained as parent compounds after the treatments. Chemicals used were 2,4-dichlorophenol; 2,4,5-trichlorophenol; pentachlorophenol; pyrene; Fenpropidin, and Trifluralin. Homogenates of the whole body tissue of each organism were prepared and total radioactivity was measured. Contaminants were then extracted into organic solvents and analysed by high-pressure liquid chromatography techniques. Chromatograms showed that most of the substances extracted were present as parent compounds in S. corneum and in L. variegatus. In contrast, for C. riparius a low proportion of the chemicals was recovered as parent compounds. These results suggest that different metabolic processes could take place in the different species.


Subject(s)
Fresh Water/chemistry , Invertebrates/metabolism , Water Pollutants, Chemical/metabolism , Animals , Biological Assay , Biotransformation , Bivalvia/metabolism , Carbon Radioisotopes , Chlorophenols/metabolism , Chromatography, High Pressure Liquid , Larva/metabolism , Oligochaeta/metabolism , Pentachlorophenol/metabolism , Piperidines/metabolism , Pyrenes/metabolism , Trifluralin/metabolism
15.
High Alt Med Biol ; 2(1): 31-40, 2001.
Article in English | MEDLINE | ID: mdl-11252696

ABSTRACT

Studies of genetic structures of Andean human populations have not been numerous, even though these studies could be used to answer questions concerning migration routes of the indigenous peoples who populated America. Such studies could provide basic genetic information and clarify uncertainties surrounding genetic relatedness of South American indigenous peoples. This present work describes, quantifies, and analyzes the digital and palmar dermatoglyphics of 120 people in the community of San Pedro de Casta, Perú. The results were then compared using distance analysis to all other Peruvian population values studied to date and other South American populations. The dermatoglyphic indicators studied were the distribution of digital pattern frequencies, the total ridge counts (TRC), the pattern intensity index (PII), the atd angle, and the a-b ridge counts. The results did not show statistically significant differences for digital patterns between hands, neither within a sex nor between sexes. The means and standard deviations of PII and TRC were 12.32 +/- 3.97 and 112.18 +/- 45.09, respectively. The means and standard deviations for the other two indicators were the following: atd angle, 94.85 degrees +/- 12.33; and a-b ridge counts, 81.57 +/- 9.06. The distance analyses results suggest the existence of two different genetic lines among high altitude populations, as well as the need for further research.


Subject(s)
Altitude , Asian People/genetics , Dermatoglyphics , Indians, South American/genetics , Adolescent , Child , Female , Humans , Male , Peru
16.
Environ Toxicol Chem ; 20(12): 2910-5, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11764179

ABSTRACT

The uptake of anthropogenic chemicals by benthic bivalves may occur through the water phase and also by the ingestion of particles from both the suspended matter and bottom sediments. Many chemicals sorb to sediments and, subsequently, are released in the digestive tract of animals. The assessment of sediment-bound chemicals has been difficult because of the complexity of the association between these chemicals and natural particles. To simplify this complexity, we previously devised a test system using artificial particles with known chemical structures. In the present work, we improved this experimental design by adding humic materials as a source of organic matter. Bioassays were conducted by exposing the fingernail clam Sphaerium corneum to sublethal levels of pentachlorophenol (PCP) in the presence or absence of the artificial particles, treated with or without a commercial preparation of humic acids. The results showed that the bioavailability and bioaccumulation could be explained on the basis of the interactions of PCP with the active groups and/or the backbone of the resins, both in systems with or without humic acids. This model may constitute a useful approach to modeling and predicting the uptake and accumulation of chemicals bound to natural sediments.


Subject(s)
Bivalvia , Environmental Exposure , Environmental Pollutants/pharmacokinetics , Models, Biological , Pentachlorophenol/pharmacokinetics , Water Pollutants, Chemical/pharmacokinetics , Animals , Biological Availability , Environmental Pollutants/analysis , Forecasting , Humic Substances/analysis , Humic Substances/pharmacokinetics , Particle Size , Pentachlorophenol/analysis , Risk Assessment , Tissue Distribution , Water Pollutants, Chemical/analysis
17.
J Pediatr ; 137(6): 833-41, 2000 Dec.
Article in English | MEDLINE | ID: mdl-11113841

ABSTRACT

UNLABELLED: The risk for premature ovarian failure (POF) in females with galactosemia can be predicted by analyzing 3 areas of risk pathology: the patient's molecular genotype for galactose-1-phosphate uridyltransferase (GALT), alternate pathways for galactose metabolism, and the patient's environment at diagnosis and during treatment. STUDY DESIGN: Retrospective cross-sectional information was collected on 53 females with classic galactosemia, and their ovarian function was analyzed by determination of serum follicle-stimulating hormone and luteinizing hormone levels and by clinical observation. The associations were analyzed between POF and the mutations in GALT, the highest erythrocyte galactose-1-phosphate (Gal-1-P) level at diagnosis, the age at which dietary treatment was initiated, mean erythrocyte Gal-1-P level during treatment, and whole-body carbon 13-labeled galactose oxidation to (13)CO(2). RESULTS: The most prevalent mutation, Q188R, had a significant effect of genotype category (Q188R/Q188R, Q188R/Other, Other/Other) on POF (P =.04, Fisher exact test and an odds ratio of 8.3). Mean erythrocyte Gal-1-P level during treatment was a significant risk factor for POF (P =.04). Also, all patients studied with less than 5% total body oxidation of galactose to (13)CO(2) had POF, whereas those with more than 5% did not have POF (P =.008, Fisher exact test). CONCLUSION: The development of POF in females with galactosemia is more likely if the patient's genotype is Q188R/Q188R, if the mean erythrocyte Gal-1-P is >3.5 mg/dL during therapy, and if the recovery of (13)CO(2) from whole-body (13)C-galactose oxidation is reduced below 5% of administered (13)C-galactose.


Subject(s)
Galactosemias/complications , Primary Ovarian Insufficiency/etiology , Adolescent , Adult , Child , Child, Preschool , Cross-Sectional Studies , Female , Follicle Stimulating Hormone/blood , Galactosemias/diet therapy , Galactosemias/genetics , Genotype , Humans , Infant , Point Mutation/genetics , Primary Ovarian Insufficiency/diagnosis , Primary Ovarian Insufficiency/epidemiology , Retrospective Studies , Risk Factors , UTP-Hexose-1-Phosphate Uridylyltransferase/blood , UTP-Hexose-1-Phosphate Uridylyltransferase/genetics
18.
Mech Dev ; 97(1-2): 47-56, 2000 Oct.
Article in English | MEDLINE | ID: mdl-11025206

ABSTRACT

The Snail family of genes comprise a group of transcription factors with characteristic zinc finger motifs. One of the members of this family is the Slug gene. Slug has been implicated in the development of neural crest in chick and Xenopus by antisense loss of function experiments. Here, we have generated functional derivatives of Xslug by constructing cDNAs that encode the Xslug protein fused with the transactivation domain of the virus-derived VP16 activator or with the repressor domain of the Drosophila Engrailed protein. Our results suggest that Xslug normally functions as a transcriptional repressor and that Xslug-VP16 behaves as a dominant negative of Xslug. In the present work, we confirm and extend previous results that suggest that Xslug has an important function in neural crest development, by controlling its own transcription. In addition we have uncovered a new function for Xslug. We show that Xslug is expressed in the dorsal mesendoderm at the beginning of gastrulation, where is it able to upregulate the expression of dorsal genes. On the other hand when Xslug is expressed outside of the organizer it represses the expression of ventral genes. Our results indicate that this effect on mesodermal patterning depends on BMP activity, showing that Xslug can directly control the transcription of BMP-4.


Subject(s)
Bone Morphogenetic Proteins/genetics , Drosophila Proteins , Gene Expression Regulation, Developmental , Glycoproteins , Intercellular Signaling Peptides and Proteins , Mesoderm/physiology , Repressor Proteins/physiology , Transcription Factors/physiology , Xenopus Proteins , Zebrafish Proteins , Animals , Biomarkers , Bone Morphogenetic Protein 4 , Cell Nucleus/metabolism , DNA-Binding Proteins/genetics , DNA-Binding Proteins/metabolism , Ectoderm/metabolism , Ectoderm/physiology , Homeodomain Proteins/genetics , Mesoderm/metabolism , Neural Crest/metabolism , Organizers, Embryonic/metabolism , PAX3 Transcription Factor , Paired Box Transcription Factors , Proteins/genetics , Proto-Oncogene Proteins/genetics , Recombinant Fusion Proteins/genetics , Recombinant Fusion Proteins/metabolism , Recombinant Fusion Proteins/physiology , Repressor Proteins/genetics , Repressor Proteins/metabolism , Snail Family Transcription Factors , Transcription Factors/genetics , Transcription Factors/metabolism , Wnt Proteins , Xenopus laevis/embryology , Zinc Fingers
19.
Pediatr Res ; 48(3): 323-8, 2000 Sep.
Article in English | MEDLINE | ID: mdl-10960497

ABSTRACT

A galactose breath test that quantitates [1-(13)C]galactose conversion to 13CO2 provides information on the whole body galactose oxidative capacity. As there is little information on the relationship between whole body oxidation and the genotype in patients with galactosemia, we measured the 13CO2 excretion for 2 h after administration of [1-(13)C]galactose in 37 patients (3-48 y old) with galactose-1-phosphate uridyltransferase (GALT) deficiency and 20 control subjects (3-37 y old). Eleven patients with the common Q188R/Q188R genotype and no detectable erythrocyte GALT activity eliminated <2% of a bolus of [1-(13)C]galactose as 13CO2 compared with 8.47 to 28.23% in controls. This defines a severe metabolic phenotype. Seven patients with one Q188R allele and a second mutant allele such as L195P, E308K, V151A, M142K, or Q344K and one patient with a K285N/unknown genotype also released <2% as 13CO2 in 2 h. The presence of N314D or S135L as the second mutant allele does not impair total body galactose oxidation, as individuals with the GALT genotype of Q188R/N314D, K285N/N314D, and Q188R/S135L had normal 2-h galactose breath tests. Subjects with S135L/S135L, N314D/N314D, S135L/deltaT2359 as well as other rarer genotypes such as R258C/Y209C, E203K/IVSC-N314D, K285N/T138M, Q188R/D113N, S135L/F171S, R148W/N314D, and IVSC-N314D/N314D oxidized galactose comparable to controls. The dissociation of residual erythrocyte GALT activity and whole body galactose oxidative capacity is exemplified by blacks with a S135L/S135L genotype and absent erythrocyte GALT activity. An oral 2-h [1-(13)C]galactose breath test distinguishes severe and variant GALT genotypes and enables delineation of the extent of impaired galactose metabolism in an array of patients who possess diverse GALT mutations. It may prove to be useful in establishing whether a patient is capable of manifesting disease similar to patients with a Q188R/Q188R genotype.


Subject(s)
Galactose/metabolism , UTP-Hexose-1-Phosphate Uridylyltransferase/genetics , UTP-Hexose-1-Phosphate Uridylyltransferase/metabolism , Adolescent , Adult , Breath Tests , Child , Child, Preschool , Female , Genetic Variation , Humans , Male , Middle Aged , Mutation , Predictive Value of Tests
20.
J Am Diet Assoc ; 100(7): 797-803, 2000 Jul.
Article in English | MEDLINE | ID: mdl-10916518

ABSTRACT

OBJECTIVE: To evaluate the effectiveness of an education intervention in a summer camp setting on knowledge, attitudes, and health beliefs regarding metabolic control of phenylketonuria and dietary compliance. DESIGN: An observational study of a weeklong metabolic camp for adolescent girls with phenylketonuria (PKU) who were followed up over the course of 1 year. Observations also were made in 3 subsequent years of camp. INTERVENTION: The camp experience consisted of diet and disease education, sessions on reproductive development, and recreation. Group discussions on attitudes and perceptions about PKU related to dietary compliance were held with nutritionists and a pediatric psychologist. OUTCOME MEASURES: Biochemical and psychological data were collected on the first and last days of the camp to assess short-term effects of the intervention, then at quarterly intervals during the year to determine the long-term impact of the camp. Precamp and Postcamp plasma amino acid data for the subsequent 3 years were also collected. SUBJECTS/SETTING: Analyses were based on 13 adolescent girls with PKU in the first year of a camp at Emory University in Atlanta, Ga, and compared with data from 11 additional campers enrolled the second year, 8 in the third year, and 7 in the fourth year. Mean age +/- standard deviation of first-year campers was 13 +/- 2 years, mean IQ +/- standard deviation was 98 +/- 16, and 9 of 13 girls had menstruated. STATISTICAL ANALYSES PERFORMED: Short-term effects of the intervention were computed by comparing mean levels of response from the baseline period to those from the last day of camp using t tests for dependent samples. Repeated-measures analysis of variance was used to assess the long-term effects of the camp experience over the course of a year at regular quarterly intervals. RESULTS: Short-term effects of the education intervention were significant reductions in dietary phenylalanine intake, plasma phenylalanine levels, and perceived isolation. However, these effects progressively returned to baseline levels over the course of a year. The significant short- and long-term effects of increased knowledge of diet and disease persisted throughout the study period. APPLICATIONS/CONCLUSIONS: Short-term effects of the education intervention resulted in improved metabolic control associated with improved attitudes, increased knowledge of diet and disease, increased perceived support, and decreased barriers to dietary compliance in a camp setting.


Subject(s)
Camping , Health Knowledge, Attitudes, Practice , Patient Education as Topic/methods , Phenylalanine/blood , Phenylketonurias/diet therapy , Adolescent , Analysis of Variance , Attitude to Health , Camping/classification , Camping/psychology , Child , Female , Health Behavior , Humans , Patient Compliance , Phenylalanine/administration & dosage , Phenylketonurias/blood , Phenylketonurias/psychology , Social Isolation/psychology , Social Support , Surveys and Questionnaires , Time Factors
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