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1.
Toxicol Rep ; 9: 945-950, 2022.
Article in English | MEDLINE | ID: mdl-35875255

ABSTRACT

Waterpipe, also known as hookah, narghile or narghila, shisha or hubbly bubbly, is a tobacco-smoking device. Waterpipe tobacco is heated and consumed by a process of inhaling tobacco smoke, that bubbles through water before being inhaled. To date, limited studies have examined the transfer of waterpipe additives from tobacco to smoke. This study was designed to investigate the filtration ability of water in the waterpipe's bowl to define exposure to additives in waterpipe smoke, which is an essential requirement to perform toxicological risk assessments of waterpipe additives. Within this study, a standard smoking protocol (ISO 22486) was used to evaluate the transfer of > 40 additives from experimental and commercially available samples. These results are the first to provide such an extensive dataset of information showing transfer rates varying between 6% and 61% depending on the additive. Various physicochemical parameters of the additives including water solubility, partition coefficient, molecular weight, boiling point, and vapor pressure were also evaluated to seek to identify any correlation to transfer rate that may be later used to predict transfer. The amount of additive transfer from waterpipe tobacco to the smoke was found to be moderately correlated to vapor pressure (Pearson correlation coefficient = 0.33) with subsequent multivariate analysis using step-wise selection indicating 39% of the transfer rate variance can be explained collectively by the additive boiling point, molecular weight, vapor pressure and water solubility. These findings underscore the complexity of additive transfer and highlight the necessity of exposure assessment for meaningful waterpipe additive risk assessments.

2.
Pol J Vet Sci ; 25(4): 535-546, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36649097

ABSTRACT

The aim of this study was to investigate the impact of feed supplements with alfa-amylase and beta-glucanase (Optipartum C+ 200) on ingestive-related behaviour biomarkers registered with real-time sensors: rumination behaviours and reticulorumen parameters (pH and temperature). Cows (n=20) in the treatment group (TG) were fed with Optipartum C+ 200 (Enzymes feed supplement: Alfa-Amylase 57 Units; Beta-Glucanase 107 Units) from 21 days before calving until 30 days after calving with a feeding rate of 200 g/cow/day. Cows (n=22) in the control group (CG) were fed a feed ration without feed supplement. Measurements started from 6 days before calving and continued until 21 days after calving. The following indicators were registered: with the RumiWatch System: Rumination time; Eating time; Drinking time; Rumination chews; Eating chews; Drinking gulps; Bolus; Chews per minute; Chews per bolus. With the SmaXtec system: the temperature, pH of the contents of the cows' reticulorumens, and cows' walking activity. According to our results, feed supplementation with alfa-amylase and beta-glucanase (Optipartum C+ 200) in the TG group resulted in increases in the following parameters: 9% rumination time and eating time, 19% drinking time, 11% rumination chews, 16% eating chews, 13% number of boluses per rumination, 5% chews per minute and 16% chews per bolus. The rumination time showed a strong, positive relation with rumination chews and bolus indicators in both groups (TG and CG) (p⟨0.001); while the rumination time in both groups of cows showed an opposite direction and was negatively related to eating time and eating chews (p⟨0.05). We found a 1.28 % lower reticulorumen pH and a 0.64 % lower reticulorumen temperature in cows fed with the supplement compared with cows in the control group. Cows in TG were 8.80% more active than those in the CG group. For improvement of ingestive-related behaviour we suggest adding a feed supplement with alfa-amylase and beta-glucanase (Optipartum C+ 200).


Subject(s)
Animal Feed , Cellulase , Dietary Supplements , Digestion , alpha-Amylases , Animals , Cattle , Female , alpha-Amylases/pharmacology , Animal Feed/analysis , Diet/veterinary , Feeding Behavior/drug effects , Cellulase/pharmacology , Digestion/drug effects
3.
J Biol Rhythms ; 36(1): 35-54, 2021 02.
Article in English | MEDLINE | ID: mdl-33491541

ABSTRACT

Not 1 year has passed since the emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of coronavirus disease 2019 (COVID-19). Since its emergence, great uncertainty has surrounded the potential for COVID-19 to establish as a seasonally recurrent disease. Many infectious diseases, including endemic human coronaviruses, vary across the year. They show a wide range of seasonal waveforms, timing (phase), and amplitudes, which differ depending on the geographical region. Drivers of such patterns are predominantly studied from an epidemiological perspective with a focus on weather and behavior, but complementary insights emerge from physiological studies of seasonality in animals, including humans. Thus, we take a multidisciplinary approach to integrate knowledge from usually distinct fields. First, we review epidemiological evidence of environmental and behavioral drivers of infectious disease seasonality. Subsequently, we take a chronobiological perspective and discuss within-host changes that may affect susceptibility, morbidity, and mortality from infectious diseases. Based on photoperiodic, circannual, and comparative human data, we not only identify promising future avenues but also highlight the need for further studies in animal models. Our preliminary assessment is that host immune seasonality warrants evaluation alongside weather and human behavior as factors that may contribute to COVID-19 seasonality, and that the relative importance of these drivers requires further investigation. A major challenge to predicting seasonality of infectious diseases are rapid, human-induced changes in the hitherto predictable seasonality of our planet, whose influence we review in a final outlook section. We conclude that a proactive multidisciplinary approach is warranted to predict, mitigate, and prevent seasonal infectious diseases in our complex, changing human-earth system.


Subject(s)
COVID-19/prevention & control , Circadian Rhythm/physiology , Communicable Diseases/transmission , SARS-CoV-2/isolation & purification , Seasons , Animals , COVID-19/epidemiology , COVID-19/virology , Communicable Diseases/diagnosis , Communicable Diseases/epidemiology , Environment , Epidemics , Host-Pathogen Interactions , Humans , SARS-CoV-2/physiology
4.
Proc Biol Sci ; 282(1817): 20151453, 2015 Oct 22.
Article in English | MEDLINE | ID: mdl-26468242

ABSTRACT

The rhythm of life on earth is shaped by seasonal changes in the environment. Plants and animals show profound annual cycles in physiology, health, morphology, behaviour and demography in response to environmental cues. Seasonal biology impacts ecosystems and agriculture, with consequences for humans and biodiversity. Human populations show robust annual rhythms in health and well-being, and the birth month can have lasting effects that persist throughout life. This review emphasizes the need for a better understanding of seasonal biology against the backdrop of its rapidly progressing disruption through climate change, human lifestyles and other anthropogenic impact. Climate change is modifying annual rhythms to which numerous organisms have adapted, with potential consequences for industries relating to health, ecosystems and food security. Disconcertingly, human lifestyles under artificial conditions of eternal summer provide the most extreme example for disconnect from natural seasons, making humans vulnerable to increased morbidity and mortality. In this review, we introduce scenarios of seasonal disruption, highlight key aspects of seasonal biology and summarize from biomedical, anthropological, veterinary, agricultural and environmental perspectives the recent evidence for seasonal desynchronization between environmental factors and internal rhythms. Because annual rhythms are pervasive across biological systems, they provide a common framework for trans-disciplinary research.


Subject(s)
Ecosystem , Food Supply , Periodicity , Seasons , Agriculture , Animals , Biodiversity , Climate Change , Humans , Plants
5.
Clin Genet ; 88(3): 224-33, 2015 Sep.
Article in English | MEDLINE | ID: mdl-25131214

ABSTRACT

Studies of genomic copy number variants (CNVs) have identified genes associated with autism spectrum disorder (ASD) and intellectual disability (ID) such as NRXN1, SHANK2, SHANK3 and PTCHD1. Deletions have been reported in PTCHD1 however there has been little information available regarding the clinical presentation of these individuals. Herein we present 23 individuals with PTCHD1 deletions or truncating mutations with detailed phenotypic descriptions. The results suggest that individuals with disruption of the PTCHD1 coding region may have subtle dysmorphic features including a long face, prominent forehead, puffy eyelids and a thin upper lip. They do not have a consistent pattern of associated congenital anomalies or growth abnormalities. They have mild to moderate global developmental delay, variable degrees of ID, and many have prominent behavioral issues. Over 40% of subjects have ASD or ASD-like behaviors. The only consistent neurological findings in our cohort are orofacial hypotonia and mild motor incoordination. Our findings suggest that hemizygous PTCHD1 loss of function causes an X-linked neurodevelopmental disorder with a strong propensity to autistic behaviors. Detailed neuropsychological studies are required to better define the cognitive and behavioral phenotype.


Subject(s)
Autism Spectrum Disorder/diagnosis , Autism Spectrum Disorder/genetics , Intellectual Disability/diagnosis , Intellectual Disability/genetics , Membrane Proteins/genetics , Mutation , Phenotype , Sequence Deletion , Adolescent , Adult , Child , Child, Preschool , Exons , Facies , Female , Humans , Infant , Male , Young Adult
6.
J Insect Physiol ; 64: 81-9, 2014 May.
Article in English | MEDLINE | ID: mdl-24662466

ABSTRACT

Many insects are tolerant of hypoxic conditions, but survival may come at a cost to long-term health. The alfalfa leaf-cutting bee, Megachile rotundata, develops in brood cells inside natural cavities, and may be exposed to hypoxic conditions for extended periods of time. Whether M. rotundata is tolerant of hypoxia, and whether exposure results in sub-lethal effects, has never been investigated. Overwintering M. rotundata prepupae were exposed to 10%, 13%, 17%, 21% and 24% O2 for 11 months. Once adults emerged, five indicators of quality - emergence weight, body size, feeding activity, flight performance, and adult longevity, - were measured to determine whether adult bees that survived past exposure to hypoxia were competent pollinators. M. rotundata prepupae are tolerant of hypoxic condition and have higher survival rates in hypoxia, than in normoxia. Under hypoxia, adult emergence rates did not decrease over the 11 months of the experiment. In contrast, bees reared in normoxia had decreased emergence rates by 8 months, and were dead by 11 months. M. rotundata prepupae exposed to extended hypoxic conditions had similar emergence weight, head width, and cross-thorax distance compared to bees reared in standard 21% oxygen. Despite no significant morphological differences, hypoxia-exposed bees had lower feeding rates and shorter adult lifespans. Hypoxia may play a role in post-diapause physiology of M. rotundata, with prepupae showing better survival under hypoxic conditions. Extended exposure to hypoxia, while not fatal, causes sub-lethal effects in feeding rates and longevity in the adults, indicating that hypoxia tolerance comes at a cost.


Subject(s)
Bees/growth & development , Bees/physiology , Animals , Body Size , Diapause, Insect , Feeding Behavior , Flight, Animal , Hypoxia/pathology , Larva , Longevity , Oxygen , Seasons
7.
J Exp Biol ; 217(Pt 9): 1510-8, 2014 May 01.
Article in English | MEDLINE | ID: mdl-24436383

ABSTRACT

Animals cope with seasonal variation in environmental factors by adjustments of physiology and life history. When seasonal variation is partly predictable, such adjustments can be based on a genetic component or be phenotypically flexible. Animals have to allocate limited resources over different demands, including immune function. Accordingly, immune traits could change seasonally, and such changes could have a genetic component that differs between environments. We tested this hypothesis in genotypically distinct groups of a widespread songbird, the stonechat (Saxicola torquata). We compared variation in immunity during 1 year in long-distance migrants, short-distance migrants, tropical residents and hybrids in a common garden environment. Additionally, we investigated phenotypically flexible responses to temperature by applying different temperature regimes to one group. We assessed constitutive immunity by measuring hemagglutination, hemolysis, haptoglobin and bactericidal ability against Escherichia coli and Staphylococcus aureus. Genotypic groups differed in patterns of variation of all measured immune indices except haptoglobin. Hybrids differed from, but were rarely intermediate to, parental subspecies. Temperature treatment only influenced patterns of hemolysis and bactericidal ability against E. coli. We conclude that seasonal variation in constitutive immunity has a genetic component, that heredity does not follow simple Mendelian rules, and that some immune measures are relatively rigid while others are more flexible. Furthermore, our results support the idea that seasonal variability in constitutive immunity is associated with variability in environment and annual-cycle demands. This study stresses the importance of considering seasonal variation in immune function in relation to the ecology and life history of the organism of interest.


Subject(s)
Immunity/genetics , Immunity/physiology , Passeriformes/immunology , Seasons , Animal Migration/physiology , Animals , Climate , Escherichia coli/immunology , Phenotype , Staphylococcus aureus/immunology , Temperature
8.
Proc Biol Sci ; 280(1763): 20130593, 2013 Jul 22.
Article in English | MEDLINE | ID: mdl-23740778

ABSTRACT

To keep pace with progressing urbanization organisms must cope with extensive habitat change. Anthropogenic light and noise have modified differences between day and night, and may thereby interfere with circadian clocks. Urbanized species, such as birds, are known to advance their activity to early morning and night hours. We hypothesized that such modified activity patterns are reflected by properties of the endogenous circadian clock. Using automatic radio-telemetry, we tested this idea by comparing activity patterns of free-living forest and city European blackbirds (Turdus merula). We then recaptured the same individuals and recorded their activity under constant conditions. City birds started their activity earlier and had faster but less robust circadian oscillation of locomotor activity than forest conspecifics. Circadian period length predicted start of activity in the field, and this relationship was mainly explained by fast-paced and early-rising city birds. Although based on only two populations, our findings point to links between city life, chronotype and circadian phenotype in songbirds, and potentially in other organisms that colonize urban habitats, and highlight that urban environments can significantly modify biologically important rhythms in wild organisms.


Subject(s)
Circadian Clocks/physiology , Ecosystem , Songbirds/physiology , Animals , Circadian Rhythm , Cities , Light , Male , Songbirds/classification , Trees , Urbanization
9.
Water Sci Technol ; 67(2): 261-70, 2013.
Article in English | MEDLINE | ID: mdl-23168622

ABSTRACT

Nutrients in river systems originate from multiple emission sources, follow various pathways, and are subject to processes of conversion and fate. One approach to tackle this complexity is to apply balance-oriented models. Although these models operate on a coarse temporal and spatial scale, they are capable of assessing the significance of the different emission sources and their results can be the basis for developing integrated water quality management schemes. In this paper we propose and apply a methodology to evaluate the attributiveness of such model results with regard to the modelled emission pathways. The MONERIS (MOdelling Nutrient Emissions in RIver Systems) model is set up, assuming plausible ranges of emission levels from four principal sources. The sensitivity of model performance is computed and related to the contribution from the pathways. The approach is applied for a case study in the upper Western Bug catchment (Ukraine). Coefficient of determination (R(2)) is found insensitive against the model assumptions, at levels around 0.65 for nitrogen and 0.55 for phosphorous emissions. Relative mean absolute error is minimized around 0.2 for both nutrients, but with equifinal combinations of the varied emission pathways. Model performance is constrained by the ranges of the emission assumptions to a limited extent only.


Subject(s)
Models, Theoretical , Statistics as Topic , Water Movements , Water Resources , Computer Simulation , Geography , Nitrogen/analysis , Phosphorus/analysis , Ukraine , Water Quality
10.
Water Sci Technol ; 67(2): 424-32, 2013.
Article in English | MEDLINE | ID: mdl-23168645

ABSTRACT

The paradigm shift in recent years towards sustainable and coherent water resources management on a river basin scale has changed the subject of investigations to a multi-scale problem representing a great challenge for all actors participating in the management process. In this regard, planning engineers often face an inherent conflict to provide reliable decision support for complex questions with a minimum of effort. This trend inevitably increases the risk to base decisions upon uncertain and unverified conclusions. This paper proposes an adaptive framework for integral planning that combines several concepts (flow balancing, water quality monitoring, process modelling, multi-objective assessment) to systematically evaluate management strategies for water quality improvement. As key element, an S/P matrix is introduced to structure the differentiation of relevant 'pressures' in affected regions, i.e. 'spatial units', which helps in handling complexity. The framework is applied to a small, but typical, catchment in Flanders, Belgium. The application to the real-life case shows: (1) the proposed approach is adaptive, covers problems of different spatial and temporal scale, efficiently reduces complexity and finally leads to a transparent solution; and (2) water quality and emission-based performance evaluation must be done jointly as an emission-based performance improvement does not necessarily lead to an improved water quality status, and an assessment solely focusing on water quality criteria may mask non-compliance with emission-based standards. Recommendations derived from the theoretical analysis have been put into practice.


Subject(s)
Environment , Water Quality , Water Resources , Belgium , Pressure , Sewage/chemistry
11.
Water Sci Technol ; 66(11): 2432-8, 2012.
Article in English | MEDLINE | ID: mdl-23032775

ABSTRACT

A review of material flow analysis (MFA) tools, comparison of case studies and analysis of approximately 20 MFA tools (static, semi-empirical models) are performed. The evaluation of the quantification procedures revealed several deficits in the approaches. The following principal complications for a reliable quantification of inputs from the urban water system are identified: (1) frequently insufficient data for urban system model validation (e.g. combined sewer overflow (CSO) discharges); (2) the necessity for additionally quantifying diffuse sources in order to verify modelling results at basin scale, where both input pathways occur, and (3) the contradictions arising when describing the highly dynamic urban system with the help of static MFA models. However, a wise selection of appropriate calculation procedures with regard to the concrete systems characteristics and available data can minimize the model deviations significantly. Criteria and suggestions for designing adapted quantification procedures are given.


Subject(s)
Databases as Topic , Models, Theoretical , Water Quality , Cities , Decision Support Techniques , Rivers , Water Pollution
12.
J Exp Biol ; 215(Pt 19): 3459-66, 2012 Oct 01.
Article in English | MEDLINE | ID: mdl-22771752

ABSTRACT

Birds have adjusted their life history and physiological traits to the characteristics of the seasonally changing environments they inhabit. Annual cycles in physiology can result from phenotypic flexibility or from variation in its genetic basis. A key physiological trait that shows seasonal variation is basal metabolic rate (BMR). We studied genetic and phenotypic variation in the annual cycles of body mass, BMR and mass-specific BMR in three stonechat subspecies (Saxicola torquata) originating from environments that differ in seasonality, and in two hybrid lines. Birds were kept in a common garden set-up, under annually variable day length and at constant temperature. We also studied whether stonechats use the proximate environmental factor temperature as a cue for changes in metabolic rate, by keeping birds at two different temperature regimes. We found that the different subspecies kept in a common environment had different annual cycles of body mass, BMR (variance: Kazakh 4.12, European 1.31, Kenyans 1.25) and mass-specific BMR (variance: Kazakh 0.042, European 0.003, Kenyans 0.013). Annual variation in metabolic measures of hybrids was intermediate or similar to that of parental species. Temperature treatment did not affect the shape of the annual cycles of metabolic rate, but metabolic rate was higher in birds kept under the variable temperature regime. The distinct annual cycles in body mass and metabolic rate in stonechat subspecies kept in a common environment indicate different genetic backgrounds rather than merely a phenotypically flexible response to proximate environmental cues. Phenotypic effects of temperature are superimposed on this genetically orchestrated annual cycle.


Subject(s)
Basal Metabolism/physiology , Passeriformes/genetics , Passeriformes/physiology , Seasons , Animals , Body Weight/physiology , Hybridization, Genetic , Phenotype , Species Specificity , Temperature
13.
J Evol Biol ; 23(5): 1050-63, 2010 May.
Article in English | MEDLINE | ID: mdl-20345819

ABSTRACT

Migration promotes utilization of seasonal resources, and the distance flown is associated with specific morphologies, yet these relationships can be confounded by environmental factors and phylogeny. Understanding adaptations associated with migration is important: although migration patterns change rapidly, it is unclear whether migratory traits track behavioural shifts. We studied morphometrics of four stonechat populations representing a migratory gradient and raised under common-garden conditions. With multivariate analyses, we identified wing traits that differed clearly from general size trends, and used phylogenetic comparative methods to test the prediction that these traits correlated with migratory distance in captive and wild populations. Pointedness differed among populations, changed independently from overall body size, and was correlated with migration distance. Migration in stonechats may lead to deviations from allometric size changes, suggesting that birds may adapt morphologically to selection pressures created by their own behaviour in response to changing environmental conditions.


Subject(s)
Adaptation, Biological/physiology , Animal Migration/physiology , Biological Evolution , Passeriformes/anatomy & histology , Wings, Animal/anatomy & histology , Age Factors , Animals , Bayes Theorem , Body Weights and Measures , Passeriformes/physiology , Phylogeny , Regression Analysis
14.
Rapid Commun Mass Spectrom ; 20(4): 529-36, 2006.
Article in English | MEDLINE | ID: mdl-16419021

ABSTRACT

A multi-residue method for the determination of carbamates in tobacco was developed by high-performance liquid chromatography (HPLC) triple quadrupole mass spectrometry (MS). A rapid sample preparation consisted of an extraction step with methanol, centrifugation and 1:1 dilution with aqueous 10 mM ammonium acetate. After filtration these extracts were directly analysed by reversed-phase HPLC coupled to positive electrospray ionisation tandem mass spectrometry operated in the multiple reaction monitoring mode. Capillary voltage and dwell times were optimised to reduce matrix effects and to increase sensitivity. The method was validated for the determination of 18 carbamates in three main types of raw tobacco and three tobacco products. The interday accuracy ranged between 80 and 110% with a relative standard deviation (RSD) of <30%. The limits of quantification (LOQs) ranged between 0.01 and 0.04 ppm for almost all carbamates, except aldicarb sulfone, carbofuran, and pebulate, with LOQs between 0.10 and 0.20 ppm. These LOQs were clearly below the guidance residue levels defined by the Agrochemical Advisory Committee of CORESTA, an association of organisations having scientific research relative to tobacco.


Subject(s)
Carbamates/analysis , Nicotiana/chemistry , Carbamates/chemistry , Chromatography, High Pressure Liquid , Pesticide Residues/analysis , Pesticide Residues/chemistry , Reference Standards , Sensitivity and Specificity , Spectrometry, Mass, Electrospray Ionization
16.
J Chromatogr B Analyt Technol Biomed Life Sci ; 771(1-2): 289-301, 2002 May 05.
Article in English | MEDLINE | ID: mdl-12016005

ABSTRACT

This review discusses some of our recent studies on rat basophilic leukaemia (RBL) cells, a model cell line for mast cell function. Our interest in these cells is a consequence of the role played by mast cells in the allergic response. Thus far we have described the identification of several spots, and their pI/M(r) co-ordinates. Here we describe how we can further decipher the mast cell proteome using a variety of staining/immuno-blotting procedures. We demonstrate the sensitivity of staining procedures and immuno-blotting using an anti-phosphotyrosine antibody. Our aim is to contribute to the ever-expanding two-dimensional gel and phosphoprotein databases currently available.


Subject(s)
Leukemia, Basophilic, Acute/metabolism , Neoplasm Proteins/metabolism , Animals , Databases, Protein , Electrophoresis, Gel, Two-Dimensional , Neoplasm Proteins/isolation & purification , Rats , Sensitivity and Specificity
17.
Surg Endosc ; 16(3): 450-2, 2002 Mar.
Article in English | MEDLINE | ID: mdl-11928026

ABSTRACT

BACKGROUND: The risk factors for gallstone disease are well known, but they have not been updated to take the development of better ultrasound technology and the advent of laparoscopic surgery into consideration. METHODS: We compared two groups of patients who underwent ultrasound-one group (n = 100) who underwent cholecystectomy after ultrasound revealed the presence of gallstones and a control group (n = 107) in whom no gallstones were shown on ultrasound. RESULTS: Seven patients in the control group refused to participate in the study; otherwise, the groups are sequential. Age in the surgery group was 51 years (+/- 16) vs 50 (+/- 16) for the control group. The percentage of female patients was 59% and 52%, respectively (p = ns). Body mass index was 32 (+/- 8) and 28 (+/- 6), respectively (p = 0.013). Parity > 2 was 0.49% and 0.37%, respectively (p = 0.000001). The number who breast-fed at least one child was 17 (24%) and eight (12%), respectively (p = 0.03). Oral contraceptive use was 37 (52%) and 17 (22%), respectively (p = 0.0005). Primary relatives who had had gallbladder surgery was 0.68 (+/- 1) and 0.35 (+/- 0.6), respectively (p = 0.02). CONCLUSION: Body mass index, breast-feeding, oral contraceptives, parity > 2, and family history were found to be risk factors for gallstone disease. Age and female sex were not, probably due to selection bias.


Subject(s)
Cholelithiasis/etiology , Body Mass Index , Case-Control Studies , Cholecystectomy/statistics & numerical data , Cholelithiasis/diagnostic imaging , Cholelithiasis/surgery , Contraceptives, Oral/administration & dosage , Family , Female , Humans , Male , Middle Aged , Parity , Risk Factors , Ultrasonography
18.
Eur J Cell Biol ; 80(4): 295-302, 2001 Apr.
Article in English | MEDLINE | ID: mdl-11370744

ABSTRACT

The expression of several isoforms of the small-molecular-weight Rab3 GTP-binding proteins is a characteristic feature of all cell types undergoing regulated exocytosis, in which Rab3 proteins are considered to regulate the assembly/disassembly of a fusion complex between granule and plasma membrane in a positive and negative manner through interaction with effector proteins. The pattern of Rab3 protein expression may, therefore, provide a subtle means of regulating exocytosis. To investigate the relationship between Rab3 expression and secretory activity, we assessed the differential expression of individual Rab3 proteins in high- and low-secreting clones of the rat basophilic (RBL) cell line. mRNAs for Rab3 isoforms (a-d) were analyzed by constructing cDNA libraries of high- and low-secreting RBL clones. The relative abundance of mRNAs for Rab3 isoforms was initially determined from the clonal frequency of corresponding cDNA clones. RT-PCR using isoform-specific primers was successfully applied to the quantitation of Rab3a mRNA. The presence of individual Rab3 proteins was revealed by SDS-PAGE and immunoblotting, and also by in situ immunofluorescence confocal microscopy. We present evidence that Rab3a and Rab3c are expressed at high levels in the low-secreting variant, while Rab3d is predominant in the high secretor. Levels of the Rab3 effector proteins, Rabphilin and Noc2, are similar in both RBL cell lines. Subcellular fractionation of unstimulated high and low secretor RBL clones revealed that in both cell types Rab3a has a cytoplasmic location while Rab3d is present in a membrane/organelle fraction containing secretory vesicles. Differences in the pattern of expression of Rab3 isoforms in the two RBL cell lines and their localisation may influence the secretory potential. Furthermore, the presence of Rab3 and effector proteins indicates that the mechanism for regulated exocytosis in cells of mast cells/basophil lineage appears similar to that in pre-synaptic vesicles and pancreatic beta-cells.


Subject(s)
Mast Cells/metabolism , Mast Cells/physiology , rab3 GTP-Binding Proteins/genetics , Adaptor Proteins, Signal Transducing , Animals , Basophils/cytology , Basophils/metabolism , Basophils/physiology , Blotting, Western , Cell Line , Fluorescent Antibody Technique , Gene Expression/physiology , Gene Library , Genetic Testing , Intracellular Signaling Peptides and Proteins , Isomerism , Mast Cells/cytology , Nerve Tissue Proteins/analysis , Phenotype , Proteins/analysis , RNA, Messenger/analysis , Rats , Reverse Transcriptase Polymerase Chain Reaction , Secretory Vesicles/chemistry , Vesicular Transport Proteins , rab GTP-Binding Proteins/analysis , rab3 GTP-Binding Proteins/analysis , rab3 GTP-Binding Proteins/chemistry , Rabphilin-3A
19.
Anim Behav ; 60(6): 899-902, 2000 Dec.
Article in English | MEDLINE | ID: mdl-11124889
20.
Z Gastroenterol ; 38(9): 785-9, 2000 Sep.
Article in German | MEDLINE | ID: mdl-11072674

ABSTRACT

Infections with Bartonella henselae or Bartonella quintana present with vasoproliferative lesions in skin and parenchymatous organs in immunocompromised patients. A case report of a 38-year-old patient with HIV infection and hepatitis B surface antigen status is described. The dominant clinical symptoms in our patient were fever and icterus. Ultrasonography of the abdomen showed a picture similar to that of liver cirrhosis. Irregular (echorich) nodes with hyper-vascularization were suspected to be hepatocellular carcinoma. Ultrasound guided puncture of one of these lesions and histological examination revealed the diagnosis of bartonella infection. Under antibiotic treatment with clarithromycin and doxycycline the fever and the hyperbilirubinemia decreased. The sonographically detectable lesions reduced in size. Vasoproliferative lesions in immunodeficient patients caused by bartonella infection show a characteristic slightly hyperechogenic irregular pattern at ultrasound. Typically, circumscribed hypervascularization might be shown by color Doppler imaging. Liver cirrhosis and diffuse tumor infiltration should be excluded.


Subject(s)
AIDS-Related Opportunistic Infections/diagnostic imaging , Angiomatosis, Bacillary/diagnostic imaging , Liver Diseases/diagnostic imaging , AIDS-Related Opportunistic Infections/pathology , Adult , Angiomatosis, Bacillary/pathology , Biopsy, Needle , Diagnosis, Differential , Hepatitis B, Chronic/diagnostic imaging , Hepatitis B, Chronic/pathology , Humans , Liver/diagnostic imaging , Liver/pathology , Liver Diseases/pathology , Male , Ultrasonography
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