Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 62
Filter
1.
Stud Mycol ; 89: 105-115, 2018 Mar.
Article in English | MEDLINE | ID: mdl-29910517

ABSTRACT

Late blight, caused by the oomycete pathogen Phytophthora infestans, is the most devastating disease in potato. For sustainable management of this economically important disease, resistance breeding relies on the availability of resistance (R) genes. Such R genes against P. infestans have evolved in wild tuber-bearing Solanum species from North, Central and South America, upon co-evolution with cognate avirulence (Avr) genes. Here, we report how effectoromics screens with Avr2 of P. infestans revealed defense responses in diverse Solanum species that are native to Mexico and Peru. We found that the response to AVR2 in the Mexican Solanum species is mediated by R genes of the R2 family that resides on a major late blight locus on chromosome IV. In contrast, the response to AVR2 in Peruvian Solanum species is mediated by Rpi-mcq1, which resides on chromosome IX and does not belong to the R2 family. The data indicate that AVR2 recognition has evolved independently on two genetic loci in Mexican and Peruvian Solanum species, respectively. Detached leaf tests on potato cultivar 'Désirée' transformed with R genes from either the R2 or the Rpi-mcq1 locus revealed an overlapping, but distinct resistance profile to a panel of 18 diverse P. infestans isolates. The achieved insights in the molecular R - Avr gene interaction can lead to more educated exploitation of R genes and maximize the potential of generating more broad-spectrum, and potentially more durable control of the late blight disease in potato.

2.
J Genet Couns ; 26(3): 576-585, 2017 Jun.
Article in English | MEDLINE | ID: mdl-27822877

ABSTRACT

This pilot study investigated the feasibility and preliminary efficacy of an Internet Support Group (ISG) for parents of children with NF1. Eligible parents were recruited by email and completed baseline questionnaires assessing social support, self-efficacy, depression, and anxiety. The ISG involved eight weekly 90-min chat sessions and a discussion forum open 24 h/day for 8 weeks. Follow-up measures were completed immediately post-intervention and 3 months later. Parents from 33 families (29 mothers, 4 fathers) completed baseline measures. Over half of parents (52 %) rated their child's disease severity as mild, 33 % moderate, and 15 % severe. Among 21 parents who completed post-intervention measures, ratings of perceived emotional (p = .0008) and informational (p = .0003) support increased. There were no significant changes in self-efficacy, depression, or anxiety (ps > .05). The mean satisfaction rating was moderately high (7.6/10; range 4-10). Some parents commented that the chat sessions were at inconvenient times, which may have limited participation. Preliminary evidence in this small sample of parents suggests that ISGs may be a feasible and potentially efficacious method of providing support to parents of children with NF1. Having multiple weekly chat sessions held at various days and times may improve accessibility and participation. Clinicians are encouraged to help parents access online support resources.


Subject(s)
Internet , Neurofibromatosis 1/nursing , Parents/psychology , Self-Help Groups , Social Support , Adolescent , Adult , Child , Child, Preschool , Feasibility Studies , Female , Humans , Infant , Male , Middle Aged , Pilot Projects , Young Adult
3.
Eur Respir J ; 39(2): 352-8, 2012 Feb.
Article in English | MEDLINE | ID: mdl-22183478

ABSTRACT

Some patients with idiopathic pulmonary fibrosis experience acute exacerbations in their respiratory status leading to substantial morbidity and mortality. Occult aspiration of gastric contents has been proposed as one possible mechanism leading to these acute exacerbations. We sought to determine whether pepsin, a marker of gastric aspiration, is elevated in bronchoalveolar lavage fluid obtained from patients during acute exacerbation of idiopathic pulmonary fibrosis, compared with that obtained in stable disease. Lavage samples were obtained in a case-control study of well-characterised patients. Acute exacerbation was defined using standard criteria. Levels of lavage pepsin were compared in cases and controls, and were correlated with clinical features and disease course. 24 cases with acute exacerbations and 30 stable controls were identified. There were no significant differences in baseline demographics between the two groups. Pepsin level was an indicator of acute exacerbation status (p=0.04). On average, pepsin appeared higher in patients with acute exacerbations compared with stable controls. This difference was driven by a subgroup of eight patients (33%) with pepsin levels ≥70 ng·mL(-1). Pepsin level was not an independent predictor of survival time. These results suggest occult aspiration may play a role in some cases of acute exacerbation of idiopathic pulmonary fibrosis.


Subject(s)
Bronchoalveolar Lavage Fluid/chemistry , Idiopathic Pulmonary Fibrosis/metabolism , Idiopathic Pulmonary Fibrosis/mortality , Pepsin A/metabolism , Respiratory Aspiration/metabolism , Respiratory Aspiration/mortality , Acute Disease , Aged , Case-Control Studies , Female , Humans , Longitudinal Studies , Male , Middle Aged , Pepsin A/analysis , Predictive Value of Tests , Radiography , Respiratory Aspiration/diagnostic imaging , Survival Analysis
4.
J Neural Eng ; 4(2): 54-67, 2007 Jun.
Article in English | MEDLINE | ID: mdl-17409480

ABSTRACT

To properly observe induced connectivity changes after training sessions, one needs a network model that describes individual relationships in sufficient detail to enable observation of induced changes and yet reveals some kind of stability in these relationships. We analyzed spontaneous firing activity in dissociated rat cortical networks cultured on multi-electrode arrays by means of the conditional firing probability. For all pairs (i, j) of the 60 electrodes, we calculated conditional firing probability (CFP(i,j)[tau]) as the probability of an action potential at electrode j at t = tau, given that one was detected at electrode i at t = 0. If a CFP(i,j)[tau] distribution clearly deviated from a flat one, electrodes i and j were considered to be related. For all related electrode pairs, a function was fitted to the CFP-curve to obtain parameters for 'strength' and 'delay' (i.e. maximum and latency of the maximum of the curve) of each relationship. In young cultures the set of identified relationships changed rather quickly. At 16 days in vitro (DIV) 50% of the set changed within 2 days. Beyond 25 DIV this set stabilized: during a week more than 50% of the set remained intact. Most individual relationships developed rather gradually. Moreover, beyond 25 DIV relational strength appeared quite stable, with coefficients of variation (100 x SD/mean) around 25% in periods of approximately 10 h. CFP analysis provides a robust method to describe the underlying probabilistic structure of highly varying spontaneous activity in cultured cortical networks. It may offer a suitable basis for plasticity studies, in the case of changes in the probabilistic structure. CFP analysis monitors all pairs of electrodes instead of just a selected one. Still, it is likely to describe the network in sufficient detail to detect subtle changes in individual relationships.


Subject(s)
Action Potentials/physiology , Biological Clocks/physiology , Models, Neurological , Models, Statistical , Nerve Net/physiology , Neurons/physiology , Animals , Animals, Newborn , Cells, Cultured , Computer Simulation , Rats , Rats, Wistar
5.
Eur Respir J ; 29(1): 210-4, 2007 Jan.
Article in English | MEDLINE | ID: mdl-16870664

ABSTRACT

An association of neurofibromatosis with diffuse lung disease (NF-DLD) has been described, but its true prevalence and characteristics remain unclear. The objective of the present study was to define diffuse lung disease in patients with neurofibromatosis. A retrospective case series and literature review in a tertiary care academic medical centre is reported in which medical records, chest radiographs and high-resolution computed tomography (HRCT) scans were reviewed. A total of 55 adult patients with neurofibromatosis were identified, three of whom had NF-DLD. A literature review revealed 16 articles reporting 61 additional cases, yielding a total of 64 NF-DLD cases. The mean age of patients was 50 yrs. Males outnumbered females; most reported dyspnoea. Of the 16 subjects with documented smoking histories, 12 were ever-smokers. Eight patients had HRCT scan results demonstrating ground-glass opacities (37%), bibasilar reticular opacities (50%), bullae (50%), cysts (25%) and emphysema (25%); none had honeycombing. A group of 14 patients had surgical biopsy results that showed findings of interstitial fibrosis (100%) and interstitial inflammation (93%). In conclusion, neurofibromatosis with diffuse lung disease is a definable clinical entity, characterised by upper lobe cystic and bullous disease and lower lobe fibrosis. Its relationship to smoking remains unclear.


Subject(s)
Lung Diseases/diagnostic imaging , Neurofibromatoses/diagnostic imaging , Aged , Female , Humans , Lung Diseases/pathology , Male , Middle Aged , Neurofibromatoses/pathology , Radiography , Respiratory Function Tests
6.
Clin Exp Allergy ; 35(1): 82-8, 2005 Jan.
Article in English | MEDLINE | ID: mdl-15649271

ABSTRACT

BACKGROUND: Mast cell-deficient Kit(W)/Kit(W-v) mice are an important resource for studying mast cell functions in vivo. However, because they are compound heterozygotes in a mixed genetic background and are infertile, they cannot be crossed easily with other mice. OBJECTIVE: To overcome this limitation, we explored the use of Kit(W-sh)/Kit(W-sh) mice for studying mast cell biology in vivo. RESULTS: These mice are in a C57BL/6 background, are fertile and can be bred directly with other genetically modified mice. Ten-week-old Kit(W-sh)/Kit(W-sh) are profoundly mast cell-deficient. No mast cells are detected in any major organ, including the lung. Gene microarrays detect differential expression of just seven of 16,463 genes in lungs of Kit(W-sh)/Kit(W-sh) mice compared with wild-type mice, indicating that resting mast cells regulate expression of a small set of genes in the normal lung. Injecting 10(7) bone marrow-derived mast cells (BMMC) into tail veins of Kit(W-sh)/Kit(W-sh) mice reconstitutes mast cell populations in lung, stomach, liver, inguinal lymph nodes, and spleen, but not in the tongue, trachea or skin. Injection of BMMC into ear dermis or peritoneum reconstitutes mast cells locally in these tissues. When splenectomized Kit(W-sh)/Kit(W-sh) mice are intravenously injected with BMMC, mast cells circulate longer and are found more often in the liver and inguinal lymph nodes, indicating that the spleen acts as a reservoir for mast cells following injection and limits migration to some tissues. CONCLUSION: In summary, these findings show that mast cell-deficient Kit(W-sh)/Kit(W-sh) mice possess unique attributes that favour their use for studying mast cell functions in vivo.


Subject(s)
Lung/metabolism , Mast Cells/pathology , Proto-Oncogene Proteins c-kit/genetics , Animals , Gene Deletion , Gene Expression Profiling , Liver/immunology , Lung/immunology , Lymph Nodes/immunology , Mice , Mice, Inbred C57BL , Mice, Knockout , Oligonucleotide Array Sequence Analysis , Spleen/immunology
7.
AIDS Care ; 16(3): 283-92, 2004 Apr.
Article in English | MEDLINE | ID: mdl-15203422

ABSTRACT

The primary aim of this study was to examine coping strategies among families of HIV-infected children and how they relate to medical, central nervous system (CNS) and family environment factors. Caregivers of HIV-positive children (N=52) completed a family coping measure (F-COPES) and provided information regarding family environment. Data regarding medical and CNS status were obtained from patient records. Results indicated that families' passive coping and spiritual support were among the coping techniques used most often, and social support was used least often. Medical variables were unrelated to any coping styles. Families of children with CNS impairment endorsed more passive coping techniques than families of children with no apparent deficits. A trend was found for non-biological caregivers to seek out more community resources and support than biological caregivers. Findings suggest the need to target families least likely to utilize resources, and to teach them to effectively seek out and benefit from social and community supports.


Subject(s)
Adaptation, Psychological , Family/psychology , HIV Infections/psychology , Adolescent , Adult , Child , Child, Preschool , Female , Humans , Internal-External Control , Male , Social Support , Stress, Psychological/prevention & control
8.
Neurosci Lett ; 361(1-3): 86-9, 2004 May 06.
Article in English | MEDLINE | ID: mdl-15135900

ABSTRACT

Spontaneous action potentials were recorded longitudinally for 4-7 weeks from dissociated rat occipital cortex cells cultured on planar multi-electrode plates, during their development from isolated neurons into synaptically connected neuronal networks. Activity typically consisted of generalized bursts lasting up to several seconds, separated by variable epochs of sporadic firing at some of the active sites. These network bursts displayed discharge patterns with age-dependent firing rate profiles, and durations significantly increasing in the 3rd week in vitro and decreasing after about 1 month in vitro, when they evolved into short events with prompt onsets. These findings indicate that after about a month in vitro these cultured neuronal networks have developed a degree of excitability that allows almost instantaneous triggering of generalized discharges. Individual neurons tend to fire in specific and persistent temporal relationships to one another within these network bursts, suggesting that network connectivity maintains a core topology during its development.


Subject(s)
Action Potentials/physiology , Cell Differentiation/physiology , Nerve Net/physiology , Neural Pathways/physiology , Neurons/physiology , Visual Cortex/physiology , Animals , Cell Differentiation/drug effects , Cells, Cultured , Microelectrodes , Nerve Net/cytology , Nerve Net/embryology , Neural Pathways/cytology , Neural Pathways/embryology , Neurons/cytology , Rats , Synapses/physiology , Synaptic Transmission/physiology , Visual Cortex/cytology , Visual Cortex/embryology
9.
Theor Appl Genet ; 108(6): 1182-90, 2004 Apr.
Article in English | MEDLINE | ID: mdl-15067406

ABSTRACT

We have utilised polymorphic chloroplast microsatellites to analyse cytoplasmic relationships between accessions in the genera Triticum and Aegilops. Sequencing of PCR products revealed point mutations and insertions/deletions in addition to the standard repeat length expansion/contraction which most likely represent ancient synapomorphies. Phylogenetic analyses revealed three distinct groups of accessions. One of these contained all the non- Aegilops speltoides S-type cytoplasm species, another comprised almost exclusively A, C, D, M, N, T and U cytoplasm-type accessions and the third contained the polyploid Triticum species and all the Ae. speltoides accessions, further confirming that Ae. speltoides or a closely related but now extinct species was the original B-genome donor of cultivated polyploid wheat. Successive decreases in levels of genetic diversity due to domestication were also observed. Finally, we highlight the importance of elucidating longer-term evolutionary processes operating at microsatellite repeat loci.


Subject(s)
DNA, Chloroplast/genetics , Phylogeny , Poaceae/genetics , Polymorphism, Genetic , Triticum/genetics , Base Sequence , Cluster Analysis , DNA Primers , Evolution, Molecular , Microsatellite Repeats/genetics , Molecular Sequence Data , Mutation/genetics , Sequence Analysis, DNA
10.
Man Ther ; 8(4): 214-22, 2003 Nov.
Article in English | MEDLINE | ID: mdl-14559044

ABSTRACT

Attitudes and beliefs, or the treatment orientation, of health care providers appear to be important in the management of non-specific chronic low back pain (CLBP). The aims of the current study were two-fold: First of all, the physiotherapists' opinion towards various aspects of the management of CLBP was surveyed. Secondly, in a principal factor analysis, it was investigated whether underlying dimensions could be identified in order to develop the Pain Attitudes and Beliefs Scale for Physiotherapists (PABS_PT). In total, 421 physiotherapists (response rate 62.3%) participated in this study. The results suggested that the majority of physiotherapists hold the opinion that CLBP is not a dangerous condition, that sport should not be discouraged and that patients should not refrain from all physical activity. Moreover physiotherapists seem to hold the opinion that the way patients view their pain influences the progress of symptoms. Finally, physiotherapists seem to hold the opinion that therapy can completely alleviate the functional symptoms and that therapy may have been successful even if pain remains. The principal factor analysis (PAF) yielded an interpretable 2-factor model. Based on highest loading items, factor 1 was labelled 'biomedical orientation', whereas factor 2 was labelled 'behavioural orientation'. The internal consistency (Cronbach's Alpha) of factor 1 was 0.84 and for factor 2, 0.54 explaining 25.2% and 8.2%, respectively, of the total variance. Assessment of the effect of the physiotherapists' characteristics on scores on the different scales was encouraging as results pointed in the directions one would expect. Physiotherapists who attended biopsychosocial education courses had statistically significantly higher scores on the 'behavioural orientation' factor and vice versa. Biomedical specialists scored statistically significantly higher on the 'biomedical orientation' factor. Furthermore, the findings suggested that the PABS_PT discriminates between physiotherapists with a 'behavioural orientation' vs those with a 'biomedical orientation'. To examine the influence of these different treatment orientations with regard to CLBP on patient outcome is a challenge for the near future.


Subject(s)
Attitude of Health Personnel , Low Back Pain/psychology , Low Back Pain/rehabilitation , Surveys and Questionnaires/standards , Adult , Chronic Disease , Female , Humans , Male , Middle Aged , Patient Education as Topic , Physical Therapy Modalities/methods , Physician-Patient Relations , Quality Indicators, Health Care , Reproducibility of Results
11.
Eur Spine J ; 12(6): 637-44, 2003 Dec.
Article in English | MEDLINE | ID: mdl-14505118

ABSTRACT

Behavioral approaches to treating patients following lumbar disc surgery are becoming increasingly popular. The treatment method is based on the assumption that pain and pain disability are not only influenced by somatic pathology, if found, but also by psychological and social factors. A recent study highlighted the effectiveness of cognitive-behavioral interventions, as compared to no treatment, for chronic low back patients. However, to the authors' knowledge, there is no randomized controlled trial that evaluates a behavioral program for patients following lumbar disc surgery. The purpose of this study was to assess the effectiveness of a behavioral graded activity (BGA) program compared to usual care (UC) in physiotherapy following first-time lumbar disc surgery. The BGA program was a patient-tailored intervention based upon operant therapy. The essence of the BGA is to teach patients that it is safe to increase activity levels. The study was designed as a randomized controlled trial. Assessments were carried out before and after treatment by an observer blinded to treatment allocation. Patients suffering residual symptoms restricting their activities of daily living and/or work at the 6 weeks post-surgery consultation by the neurosurgeon were included. The exclusion criteria were: complications during surgery, any relevant underlying pathology, and any contraindication to physiotherapy or the BGA program. Primary outcome measures were the patient's Global Perceived Effect and the functional status. Secondary measures were: fear of movement, viewing pain as extremely threatening, pain, severity of the main complaint, range of motion, and relapses. Physiotherapists in the BGA group received proper training. Between November 1997 and December 1999, 105 patients were randomized; 53 into the UC group and 52 into the BGA group. The unadjusted analysis shows a 19.3% (95% CI: 0.1 to 38.5) statistically significant difference to the advantage of the UC group on Global Perceived Effect. This result, however, is not robust, as the adjusted analyses reveal a difference of 15.7% (95% CI: -3.9 to 35.2), which is not statistically significant. For all other outcome measures there were no statistically significant or clinically relevant differences between the two intervention groups. In general, the physiotherapists' compliance with the BGA program was satisfactory, although not all treatments, either in the BGA or the UC group, were delivered exactly as planned, resulting in less contrast between the two interventions than had been planned for. There was one re-operation in each group. The BGA program was not more effective than UC in patients following first-time lumbar disc surgery. For Global Perceived Effect there was a borderline statistically significant difference to the advantage of the UC group. On functional status and all other outcome measures there were no relevant differences between interventions. The number of re-operations was negligible, indicating that it is safe to exercise after first-time disc surgery.


Subject(s)
Intervertebral Disc Displacement/rehabilitation , Intervertebral Disc/surgery , Lumbar Vertebrae/surgery , Physical Therapy Modalities/methods , Physical Therapy Modalities/psychology , Adolescent , Adult , Aged , Humans , Intervertebral Disc Displacement/psychology , Intervertebral Disc Displacement/surgery , Low Back Pain/psychology , Low Back Pain/rehabilitation , Low Back Pain/surgery , Middle Aged , Physical Therapy Modalities/statistics & numerical data , Postoperative Care/methods , Recovery of Function/physiology , Treatment Outcome
12.
Neurosci Biobehav Rev ; 26(2): 127-85, 2002 Mar.
Article in English | MEDLINE | ID: mdl-11856557

ABSTRACT

Spontaneous bioelectric activity (SBA) taking the form of extracellularly recorded spike trains (SBA) has been quantitatively analyzed in organotypic neonatal rat visual cortex explants at different ages in vitro, and the effects investigated of both short- and long-term pharmacological suppression of glutamatergic synaptic transmission. In the presence of APV, a selective NMDA receptor blocker, 1-2- (but not 3-)week-old cultures recovered their previous SBA levels in a matter of hours, although in imitation of the acute effect of the GABAergic inhibitor picrotoxin (PTX), bursts of action potentials were abnormally short and intense. Cultures treated either overnight or chronically for 1-3 weeks with APV, the AMPA/kainate receptor blocker DNQX, or a combination of the two were found to display very different abnormalities in their firing patterns. NMDA receptor blockade for 3 weeks produced the most severe deviations from control SBA, consisting of greatly prolonged and intensified burst firing with a strong tendency to be broken up into trains of shorter spike clusters. This pattern was most closely approximated by acute GABAergic disinhibition in cultures of the same age, but this latter treatment also differed in several respects from the chronic-APV effect. In 2-week-old explants, in contrast, it was the APV+DNQX treated group which showed the most exaggerated spike bursts. Functional maturation of neocortical networks, therefore, may specifically require NMDA receptor activation (not merely a high level of neuronal firing) which initially is driven by endogenous rather than afferent evoked bioelectric activity. Putative cellular mechanisms are discussed in the context of a thorough review of the extensive but scattered literature relating activity-dependent brain development to spontaneous neuronal firing patterns.


Subject(s)
Nerve Net/physiology , Neuronal Plasticity/physiology , Periodicity , Receptors, Glutamate/physiology , Visual Cortex/physiology , Action Potentials/drug effects , Action Potentials/physiology , Animals , Excitatory Amino Acid Antagonists/pharmacology , Female , Glutamic Acid/physiology , In Vitro Techniques , Male , Nerve Net/drug effects , Nerve Net/growth & development , Neuronal Plasticity/drug effects , Rats , Synaptic Transmission/drug effects , Synaptic Transmission/physiology , Time Factors , Visual Cortex/drug effects , Visual Cortex/growth & development
13.
Theor Appl Genet ; 104(5): 840-844, 2002 Apr.
Article in English | MEDLINE | ID: mdl-12582644

ABSTRACT

The frequency of Ty1- copia-type and Ty3- gypsy-type retrotransposons in the International Triticeae EST Consortium (ITEC) database (61,942 sequences: 82% wheat, 10% barley, 8% rye) and the DuPont EST database (86,628 wheat sequences) was estimated using BLASTN searches. These ESTs were obtained from 94 cDNA libraries from different tissues (leaves, roots, spikes, flowers and seeds) and different growing conditions, excluding subtracted and normalized cDNA libraries. Triticeae EST databases were screened using four different Ty1- -copia-type, 12 reverse transcriptase sequences, and three Ty3- gypsy-type Triticeae retrotransposon sequences. Using a selection threshold of BLASTN scores higher than 100 or E values smaller than e(-20), 0.145% of the ESTs were found to be significantly similar to at least one of the retrotransposons used in the search (0.064% Ty1- copia, 0.081% Ty3- gypsy). This percentage increased to 0.176% when the BLASTN threshold was changed to E

14.
Theor Appl Genet ; 104(2-3): 399-407, 2002 Feb.
Article in English | MEDLINE | ID: mdl-12582712

ABSTRACT

Genetic variation present in 64 durum wheat accessions was investigated by using three sources of microsatellite (SSR) markers: EST-derived SSRs (EST-SSRs) and two sources of SSRs isolated from total genomic DNA. Out of 245 SSR primer pairs screened, 22 EST-SSRs and 20 genomic-derived SSRs were polymorphic and used for genotyping. The EST-SSR primers produced high quality markers, but had the lowest level of polymorphism (25%) compared to the other two sources of genomic SSR markers (53%). The 42 SSR markers detected 189 polymorphic alleles with an average number of 4.5 alleles per locus. The coefficient of similarity ranged from 0.28 to 0.70 and the estimates of similarity varied when different sources of SSR markers were used to genotype the accessions. This study showed that EST-derived SSR markers developed in bread wheat are polymorphic in durum wheat when assaying loci of the A and B genomes. A minumum of ten EST-SSRs generated a very low probability of identity (0.36x10(-12)) indicating that these SSRs have a very high discriminatory power. EST-SSR markers directly sample variation in transcribed regions of the genome, which may enhance their value in marker-assisted selection, comparative genetic analysis and for exploiting wheat genetic resources by providing a more-direct estimate of functional diversity.

15.
J Int Neuropsychol Soc ; 7(4): 491-501, 2001 May.
Article in English | MEDLINE | ID: mdl-11396551

ABSTRACT

Language deficits are a major characteristic of neurobehavioral dysfunction in pediatric HIV disease. An object decision task, which assessed reaction time facilitation following a semantic or identical prime in comparison to an unrelated prime, was used to investigate whether semantic processing abnormalities could be responsible, in part, for these deficits. Thirty children with vertically acquired HIV infection (M age 9.0 years; range 6-13) participated. Either a picture of the same object (repetition prime), a semantically related object (semantic prime), a semantically unrelated object, or a nonsense object preceded a target picture, which in 50% of the cases was a real object. Brain scans of children were rated and used together with neurobehavioral functioning to classify children as having HIV-related CNS abnormalities (n = 13) or not (n = 17). Increased semantic priming but not repetition priming was associated with a greater degree of cortical atrophy. Furthermore, CNS compromised children had significantly faster reaction times following a semantic prime compared to an unrelated prime than non-compromised patients. This facilitation following semantic priming for the CNS compromised patients (13.3%) almost equaled the facilitation following repetition priming (15.3%) while for the non-compromised patients facilitation following semantic priming (7.9%) was clearly smaller than following repetition priming (14.6%). These data suggest that HIV infection in children may result in a reduced neural network leading to impoverished semantic representations characterized by poor differentiation between closely related objects.


Subject(s)
Acquired Immunodeficiency Syndrome/virology , HIV-1/isolation & purification , Language Disorders/etiology , Semantics , Acquired Immunodeficiency Syndrome/diagnosis , Acquired Immunodeficiency Syndrome/immunology , Atrophy/pathology , Blotting, Southern , Brain/diagnostic imaging , Brain/pathology , CD4 Antigens/immunology , Child , Child, Preschool , Cognition Disorders/diagnosis , Cognition Disorders/epidemiology , Female , Humans , Language Disorders/diagnosis , Male , Neuropsychological Tests , Polymerase Chain Reaction , Reaction Time , Severity of Illness Index , Tomography, X-Ray Computed
16.
J Biol Chem ; 276(21): 18551-6, 2001 May 25.
Article in English | MEDLINE | ID: mdl-11279033

ABSTRACT

Dipeptidyl peptidase I (DPPI) is the sole activator in vivo of several granule-associated serine proteases of cytotoxic lymphocytes. In vitro, DPPI also activates mast cell chymases and tryptases. To determine whether DPPI is essential for their activation in vivo, we used enzyme histochemical and immunohistochemical approaches and solution-based activity assays to study these enzymes in tissues and bone marrow-derived mast cells (BMMCs) from DPPI +/+ and DPPI -/- mice. We find that DPPI -/- mast cells contain normal amounts of immunoreactive chymases but no chymase activity, indicating that DPPI is essential for chymase activation and suggesting that DPPI -/- mice are functional chymase knockouts. The absence of DPPI and chymase activity does not affect the growth, granularity, or staining characteristics of BMMCs and, despite prior predictions, does not alter IgE-mediated exocytosis of histamine. In contrast, the level of active tryptase (mMCP-6) in DPPI -/- BMMCs is 25% that of DPPI +/- BMMCs. These findings indicate that DPPI is not essential for mMCP-6 activation but does influence the total amount of active mMCP-6 in mast cells and therefore may be an important, but not exclusive mechanism for tryptase activation.


Subject(s)
Cathepsin C/metabolism , Mast Cells/enzymology , Serine Endopeptidases/metabolism , Animals , Cathepsin C/genetics , Cells, Cultured , Chymases , Enzyme Activation/genetics , Gene Deletion , Gene Expression Regulation, Enzymologic , Mice , Serine Endopeptidases/genetics , Tryptases
17.
J Neurovirol ; 6(5): 390-7, 2000 Oct.
Article in English | MEDLINE | ID: mdl-11031692

ABSTRACT

The relationships between viral load in plasma and cerebrospinal fluid (CSF) and computed tomography (CT) brain scan abnormalities were studied in 39 children between 0.5 and 13 years of age with symptomatic HIV-1 disease. Quantitative RNA PCR was used to determine HIV-1 RNA levels and a semiquantitative analog rating technique was used to evaluate non-contrast CT brain scans. CSF HIV-1 RNA copy number correlated significantly with CT brain scan ratings for severity of cortical atrophy (r = 0.36; P < 0.05) but not with ratings of intracerebral calcifications (r = -12; NS). The difference between these two correlations was significant (P < 0.05). Plasma HIV-1 RNA copy number did not correlate significantly with any CT brain scan ratings or with CSF viral load (r = 0.05; NS). Severity of cortical atrophy appeared to reflect the level of viral load in the CSF, supporting the notion that active HIV-1 replication in the CNS is at least in part responsible for such brain abnormalities in children. The lack of correlation of intracerebral calcifications with other CT brain scan abnormalities as well as with CSF viral load suggests that this lesion is relatively independent and may reflect a different neuropathologic process.


Subject(s)
AIDS Dementia Complex , HIV-1/isolation & purification , Viral Load , AIDS Dementia Complex/cerebrospinal fluid , AIDS Dementia Complex/pathology , AIDS Dementia Complex/virology , Atrophy , CD4-Positive T-Lymphocytes/virology , Calcinosis/cerebrospinal fluid , Calcinosis/pathology , Calcinosis/virology , Child , Child, Preschool , Female , Humans , Infant , Male , Tomography, X-Ray Computed
18.
Biochim Biophys Acta ; 1480(1-2): 245-57, 2000 Jul 14.
Article in English | MEDLINE | ID: mdl-10899625

ABSTRACT

Mast cells secrete alpha- and beta-chymases. Primate alpha-chymases generate angiotensin (AT) II by selectively hydrolyzing AT I's Phe(8)-His(9) bond. This is distinct from the AT converting enzyme (ACE) pathway. In humans, alpha-chymase is the major non-ACE AT II-generator. In rats, beta-chymases destroy AT II by cleaving at Tyr(4)-Ile(5). Past studies predicted that AT II production versus destruction discriminates alpha- from beta-chymases and that Lys(40) in the substrate-binding pocket determines alpha-chymase Phe(8) specificity. This study examines these hypotheses by comparing AT II generation by human alpha-chymase (containing Lys(40)), dog alpha-chymase (lacking Lys(40)), and mouse mMCP-4 (a beta-chymase lacking Lys(40); orthologous to AT II-destroying rat chymase rMCP-1). The results suggest that human and dog alpha-chymase generate AT II exclusively and with comparable efficiency, although dog chymase contains Ala(40) rather than Lys(40). Furthermore, AT II is the major product generated by degranulation supernatants from cultured dog mast cells, which release tryptases and dipeptidylpeptidase as well as alpha-chymase. In contrast to rMCP-1, mMCP-4 beta-chymase readily generates AT II. Although there is competing AT I hydrolysis at Tyr(4), mMCP-4 does not destroy AT II quickly once it is formed. We conclude (1) that chymases are the dominant AT I-hydrolyzing mast cell peptidases, (2) that residues other than Lys(40) are key determinants of alpha-chymase AT I Phe(8) specificity, (3) that beta-chymases can generate AT II, and (4) that alpha- and beta-chymases are not strictly dichotomous regarding AT I cleavage specificity.


Subject(s)
Angiotensin II/biosynthesis , Isoenzymes/metabolism , Mast Cells/enzymology , Serine Endopeptidases/metabolism , Amino Acid Sequence , Animals , Cell Degranulation , Chromatography, Affinity , Chymases , Dogs , Electrophoresis, Polyacrylamide Gel , Enzyme Activation , Humans , Hydrolysis , Isoenzymes/isolation & purification , Mast Cells/cytology , Mice , Models, Molecular , Rats , Recombinant Proteins/isolation & purification , Recombinant Proteins/metabolism , Serine Endopeptidases/isolation & purification
19.
J Manipulative Physiol Ther ; 23(5): 312-9, 2000 Jun.
Article in English | MEDLINE | ID: mdl-10863250

ABSTRACT

OBJECTIVE: To present the design of a trial on the effectiveness of a behavioral-graded activity model. DESIGN: Randomized clinical trial. PATIENTS: Patients undergoing first-time lumbar disk surgery who still have low-back pain at the 6-week neurosurgical consultation. INTERVENTIONS: A patient-tailored behavioral-graded activity program that is based on operant therapy. The key elements of this program are baseline measurements, goal-setting, and time-contingency. This program is compared with usual care in physiotherapy, which is pain-contingent. OUTCOME MEASURES: Primary measures are the patient's global impression of the effect and their functional status. Secondary measures are kinesiophobia, catastrophizing, pain, main complaint, range of motion, and relapses. The direct and indirect costs will also be assessed. The effect measures are rated before randomization and 3, 6, and 12 months later. DISCUSSION: Several trials have been conducted on the effectiveness of behavioral treatments. Subjects were always patients with chronic low-back pain. In this trial, we apply such a treatment in patients after first-time disk surgery in a primary care setting.


Subject(s)
Behavior Therapy/methods , Intervertebral Disc Displacement/surgery , Lumbar Vertebrae , Pain, Postoperative/therapy , Randomized Controlled Trials as Topic/methods , Adaptation, Psychological , Adult , Female , Humans , Male , Middle Aged , Pain Measurement , Pain, Postoperative/psychology , Pain, Postoperative/rehabilitation , Patient Selection , Prognosis , Random Allocation , Research Design , Sensitivity and Specificity , Time Factors , Treatment Outcome
20.
J Immunol ; 164(12): 6566-75, 2000 Jun 15.
Article in English | MEDLINE | ID: mdl-10843716

ABSTRACT

Previously, this laboratory identified clusters of alpha-, beta-, and mast cell protease-7-like tryptase genes on human chromosome 16p13.3. The present work characterizes adjacent genes encoding novel serine proteases, termed gamma-tryptases, and generates a refined map of the multitryptase locus. Each gamma gene lies between an alpha1H Ca2+ channel gene (CACNA1H) and a betaII- or betaIII-tryptase gene and is approximately 30 kb from polymorphic minisatellite MS205. The tryptase locus also contains at least four tryptase-like pseudogenes, including mastin, a gene expressed in dogs but not in humans. Genomic DNA blotting results suggest that gammaI- and gammaII-tryptases are alleles at the same site. betaII- and betaIII-tryptases appear to be alleles at a neighboring site, and alphaII- and betaI-tryptases appear to be alleles at a third site. gamma-Tryptases are transcribed in lung, intestine, and in several other tissues and in a mast cell line (HMC-1) that also expresses gamma-tryptase protein. Immunohistochemical analysis suggests that gamma-tryptase is expressed by airway mast cells. gamma-Tryptase catalytic domains are approximately 48% identical with those of known mast cell tryptases and possess mouse homologues. We predict that gamma-tryptases are glycosylated oligomers with tryptic substrate specificity and a distinct mode of activation. A feature not found in described tryptases is a C-terminal hydrophobic domain, which may be a membrane anchor. Although the catalytic domains contain tryptase-like features, the hydrophobic segment and intron-exon organization are more closely related to another recently described protease, prostasin. In summary, this work describes gamma-tryptases, which are novel members of chromosome 16p tryptase/prostasin gene families. Their unique features suggest possibly novel functions.


Subject(s)
Chromosomes, Human, Pair 16/enzymology , Mast Cells/enzymology , Multigene Family , Serine Endopeptidases/chemistry , Amino Acid Sequence , Animals , Chromosomes, Human, Pair 16/genetics , Chymases , DNA, Complementary/isolation & purification , Dogs , Exons , Humans , Introns , Membrane Proteins/chemistry , Membrane Proteins/genetics , Models, Molecular , Molecular Sequence Data , Organ Specificity/genetics , Pseudogenes , RNA, Messenger/biosynthesis , Sequence Analysis, DNA , Sequence Homology, Amino Acid , Serine Endopeptidases/biosynthesis , Serine Endopeptidases/genetics , Serine Endopeptidases/isolation & purification , Tryptases
SELECTION OF CITATIONS
SEARCH DETAIL