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T Moore

Publications and source records attributed to T Moore.

At least 55 records · Page 3Linked to original sources
PubMed2000

Miniaturization of a functional transcription assay in yeast (human progesterone receptor) in the 384- and 1536-well plate format.

Miniaturization of high throughput screening assays to high-density microplate formats (384 or 1536 wells) is currently the focus of research activity in modern drug discovery facilities. In this article, we describe the adaptation of a fluorescence-based functional transcription assay in yeast for assessing modulators of human progesterone receptor to the 384- and 1536-well microplate format, comparing the experimental results to those obtained in the well-established 96-well format. The experiences gained from the optimization of the liquid-handling procedures and the miniaturization of an enzyme assay (beta-galactosidase) were implemented. Thus optimized pipetting protocols were developed to perform a reporter gene assay in yeast in microplate formats of higher density. In the functional transcription assay in yeast, the reporter gene expression showed the expected dependence on the ligand's dose and affinity in principle in all three microplate formats. For the first time, this assay system has been established in the 1536-well microplate format using CyBi-Well 96/384/1536 as the liquid-handling unit. The comparison of the signal:background ratios showed a lower sensitivity of the assay in the microplate formats of higher density. This study is an example of a successful miniaturization of a yeast cell-based assay to high-density plate formats on the basis of a careful adaptation procedure and optimized liquid-handling conditions.

Cloning, Molecular↗
PubMed2000

The influence of age on nailfold capillary dimensions in childhood.

OBJECTIVE: To identify the influence of age on nailfold capillary dimensions in children between 6 and 15 years. METHODS: Capillary density (the number of capillaries in a 3 mm length of the distal row) and capillary dimensions were measured in 110 healthy children using the technique of nailfold video microscopy. The age groups studied were as follows: 6 to 7 years (17 children), 8 to 9 years (15 children), 10 to 11 years (34 children), 12 to 13 years (24 children), and 14 to 15 years (20 children). RESULTS: There was a significant trend for the arterial and venous diameters to rise with age. However, this trend was not present for apical or loop diameters, nor for the capillary density. Results did not differ between males and females. CONCLUSION: In studies incorporating capillary dimensions in children, results should ideally be age adjusted, and dimensions should not be categorized as normal or abnormal without taking the child's age into account.

Adolescent↗
PubMed1999

Shape representations and visual guidance of saccadic eye movements.

One hallmark of primate vision is that the direction of gaze is constantly shifting to position objects of interest appropriately on the fovea, where visual acuity is greatest. This process must involve the close cooperation of oculomotor and visual recognition mechanisms because visual details must be translated into specific motor commands. This paper describes the correspondence between the presaccadic activity of V4 neurons and the degree of visual guidance of saccadic eye movements to objects of different form. The results suggest that neurons that participate in coding visual stimuli are also involved in guiding the eyes to prominent features of objects.

Animals↗
PubMed1999

The transcriptional program in the response of human fibroblasts to serum.

The temporal program of gene expression during a model physiological response of human cells, the response of fibroblasts to serum, was explored with a complementary DNA microarray representing about 8600 different human genes. Genes could be clustered into groups on the basis of their temporal patterns of expression in this program. Many features of the transcriptional program appeared to be related to the physiology of wound repair, suggesting that fibroblasts play a larger and richer role in this complex multicellular response than had previously been appreciated.

Blood↗
PubMed1999

Laser doppler imaging--a new technique for quantifying microcirculatory flow in patients with primary Raynaud's phenomenon and systemic sclerosis.

This was a pilot study to investigate the new technique of laser Doppler imaging (scanning laser Doppler) as a tool to quantify microvascular blood flow in the digits of patients with primary Raynaud's phenomenon (PRP) and systemic sclerosis (SSc), and to determine in the first instance whether the flux patterns obtained differ between patients with SSc, patients with PRP, and healthy control subjects. Laser Doppler images of the dorsum of the hand and fingers were acquired at 23 and 30 degrees C in 17 healthy control subjects, 7 patients with PRP, 9 patients with the diffuse cutaneous variant of SSc, and 24 patients with the limited cutaneous variant of SSc. Different flux parameters were compared between groups. Analysis of variance found significant differences between groups in two tests: maximum difference in flux between fingertips of the same hand at 23 degrees C (P = 0.001) and maximum gradient in flux along a finger ("distal-dorsal" flux difference) at 30 degrees C (P = 0. 019). Post hoc tests highlighted the differences between controls and patients with limited cutaneous SSc. This pilot study suggests that laser Doppler imaging may allow objective measurement of microvascular flow in patients with PRP and SSc. This new technique may overcome many of the problems inherent in single-channel laser Doppler equipment.

Adult↗
PubMed1999

Altered sodium perception in essential hypertensive patients following rapid volume expansion.

We investigated sodium and volume-dependent mechanisms in the modulation of adrenal and renal vascular responsiveness to angiotensin II in hypertensive (n = 9) and normal subjects (n = 5) who demonstrated normal responses during steady-state salt balance (intact modulation). Adrenal and renal vascular responses to angiotensin II were assessed on four occasions. These studies were performed during steady-state high salt and low salt balance and later during non-steady state conditions, after acute volume expansion with normal saline or dextran infusions. The volume expansion studies were administered while study subjects were in low salt balance. In both the normal and hypertensive patients saline and dextran suppressed plasma renin activity and aldosterone release, induced renal vasodilation and enhanced the renal vascular response to angiotensin II, similar to that observed during high salt balance. Saline also reduced the adrenal response to angiotensin II in normal subjects but the adrenal response to angiotensin II in hypertensives remained enhanced. The slopes of regression lines relating angiotensin II and aldosterone following saline infusion were significantly different (P < 0.05) between normal subjects (21 +/- 6) and hypertensives (110 +/- 33). Volume expansion with dextran did not effect the normal or hypertensive adrenal response to angiotensin II. We have demonstrated that the renal vascular response to angiotensin II is rapidly modulated by volume expansion per se in normal subjects and hypertensive patients with intact steady-state renin-angiotensin-aldosterone system responses. However, hypertensives have a delay in resetting the adrenal responsiveness to angiotensin II suggesting that they have altered sodium perception during rapid changes in salt balance.

Adrenal Cortex↗
PubMed1999

The intercellular adhesion molecule type-1 is required for rapid activation of T helper type 1 lymphocytes that control early acute phase of genital chlamydial infection in mice.

Recent studies in animal models of genital chlamydial disease revealed that early recruitment of dendritic cells and specific T helper type-1 (Th1) cells into the genital mucosae is crucial for reducing the severity of the acute phase of a cervico-vaginal infection and arresting ascending disease. These immune effectors are therefore important for preventing major complications of genital chlamydial infection. Other in vitro studies showed that intercellular adhesion molecule-1 (ICAM-1) plays a role in the antichlamydial action of specific CD4+ and CD8+ T cells. In the present study, we investigated the clinicopathological consequences of ICAM-1 deficiency during chlamydial genital infection in ICAM-1 knockout (ICAM-1KO) mice, and analysed the cellular and molecular immunological bases for any observed pathology or complication. Following a primary genital infection of female ICAM-l-/- and ICAM-1+/+ mice, the intensity of the disease during the first 3 weeks (as assessed by shedding of chlamydiae in the genital tract) was significantly greater in ICAM-1KO mice than in ICAM-1+/+ mice (P < 0.0001), although both ICAM-l-/- and ICAM-1+/+ mice subsequently cleared the primary infection. There was greater ascending disease during the initial stage of the infection, and a higher incidence of tubal disease (hydrosalpinx formation) after multiple infections in ICAM-l-/- mice. Analysis of the cellular and molecular bases for the increased acute and ascending disease in ICAM-l-/- mice revealed that the high affinity of ICAM-1 for leucocyte function antigen type-1 is a property that promotes rapid activation of specific Th1 cells, as well as their early recruitment into the genital mucosa. Moreover, ICAM-1 was more important for naive T-cell activation than primed Th1 cells, although its absence delayed or suppressed immune T-cell activation by at least 50%. Taken together, these results indicated that ICAM-1 is crucial for rapid T-cell activation, early recruitment and control of genitally acquired Chlamydia trachomatis.

Acute Disease↗
PubMed1999

Missense mutations in the most ancient residues of the PAX6 paired domain underlie a spectrum of human congenital eye malformations.

Mutations of the human PAX6 gene underlie aniridia (congenital absence of the iris), a rare dominant malformation of the eye. The spectrum of PAX6 mutations in aniridia patients is highly biased, with 92% of all reported mutations leading to premature truncation of the protein (nonsense, splicing, insertions and deletions) and just 2% leading to substitution of one amino acid by another (missense). The extraordinary conservation of the PAX6 protein at the amino acid level amongst vertebrates predicts that pathological missense mutations should in fact be common even though they are hardly ever seen in aniridia patients. This indicates that there is a heavy ascertainment bias in the selection of patients for PAX6 mutation analysis and that the 'missing' PAX6 missense mutations frequently may underlie phenotypes distinct from textbook aniridia. Here we present four novel PAX6 missense mutations, two in association with atypical phenotypes: ectopia pupillae (displaced pupils) and congenital nystagmus (searching gaze), and two in association with more recognizable aniridia phenotypes. Strikingly, all four mutations are located within the PAX6 paired domain and affect amino acids which are highly conserved in all known paired domain proteins. Our results support the hypothesis that the under-representation of missense mutations is caused by ascertainment bias and suggest that a substantial burden of PAX6 -related disease remains to be uncovered.

Amino Acid Sequence↗
PubMed1999

Anatomy of the distal knee joint and pyarthrosis following external fixation.

OBJECTIVE: To determine the limits of the distal synovial reflection of the human knee joint. SPECIMENS: Six paired knees studied by magnetic resonance imaging (MRI), fluoroscopic arthrography, and gross dissection. The right knees of five patients with chronic idiopathic knee effusions were studied by MRI. Cadaveric knees were injected with saline prior to MRI. The joint capsules were dissected to visualize local anatomy and check for capsular tears. In each modality (MRI, fluoroscopy, and dissection), the most distal extent of knee synovial fluid was measured. RESULTS: The right versus left agreement for paired specimens was generally two to three millimeters. Some specimens showed asymmetric capsular reflection. Medial fluid was identified at distances greater than forty-nine millimeters from the subchondral bone in seven knees and less than fifteen millimeters in four knees (range 0 to 70 millimeters, mean thirty-three millimeters). Laterally, the range was ten to thirty-five millimeters (mean twenty-three millimeters). In six of the twelve cadaveric specimens, there was evidence of a communication between the knee joint and the proximal tibiofibularjoint. In the knees of volunteers, joint fluid tracked medially to a range of ten to fifty millimeters and laterally to a range of six to fifteen millimeters, with means of twenty-six and eleven millimeters, respectively. The knees of the volunteers had no evidence of tibiofibular joint communication with the knee. CONCLUSION: Insertion of external fixation pins within sixty to seventy millimeters of the proximal articular surface of the tibia is associated with a high probability of synovial penetration and possibly provides a conduit for the introduction of bacteria, which may be etiologic in iatrogenic pyarthrosis.

Adult↗
PubMed1999

The "distal-dorsal difference" as a possible predictor of secondary Raynaud's phenomenon.

OBJECTIVE: To investigate the possibility that a hand distal-dorsal difference in temperature of greater than 1 degree C (fingers colder than the dorsum) at a room temperature of 30 degrees C is a good predictor of secondary Raynaud's phenomenon (RP). METHODS: We imaged the hands of patients with primary Raynaud's phenomenon (PRP) and systemic sclerosis (SSc) using a thermal camera at room temperatures of 23 and 30 degrees C. From these images we measured the distal-dorsal difference in temperature for all fingers excluding the thumbs. At a room temperature of 23 degrees C we also performed a cold challenge test using water at 15 degrees C for 1 min and thermally imaged the rewarming process for 15 min. Several variables were derived from the rewarming curve. The procedure was repeated within 3 days to assess reproducibility. RESULTS: The best discriminator between PRP and SSc was found to be a distal-dorsal difference of > 1 degree C at 30 degrees C (p = 0.005). There is reasonable reproducibility when considering groups of patients. However, the intra-subject standard deviations were large, indicating that measurements for the same patient on separate visits may vary considerably. CONCLUSION: Our results suggest that the finding of a distal-dorsal difference of > 1 degree C (cold fingers) at 30 degrees C in a patient with RP is specific for underlying connective tissue disease.

Adolescent↗
PubMed1999

Genetic analysis of the guanylate cyclase activator 1B (GUCA1B) gene in patients with autosomal dominant retinal dystrophies.

The guanylate cyclase activator proteins (GCAP1 and GCAP2) are calcium binding proteins which by activating Ret-GC1 play a key role in the recovery phase of phototransduction. Recently a mutation in the GUCA1A gene (coding for GCAP1) mapping to the 6p21.1 region was described as causing cone dystrophy in a British family. In addition mutations in Ret-GC1 have been shown to cause Leber congenital amaurosis and cone-rod dystrophy. To determine whether GCAP2 is involved in dominant retinal degenerative diseases, the GCAP2 gene was screened in 400 unrelated subjects with autosomal dominant central and peripheral retinal dystrophies. A number of changes involving the intronic as well as the coding sequence were observed. In exon 1 a T to C nucleotide change was observed leaving the tyrosine residue 57 unchanged. In exon 3 a 1 bp intronic insertion, a single nucleotide substitution G to A in the intron 3' of this exon, and a GAG to GAT change at codon 155 were observed. This latter change results in a conservative change of glutamic acid to aspartic acid. In exon 4 a 7 bp intronic insertion, a single nucleotide A to G substitution in the intron 5' of this exon, and a single base pair change C to G in the intron 3' of exon 4 were seen. None of these changes would be expected to affect correct splicing of this gene. All these changes were observed in controls. The results of this study do not show any evidence so far that GCAP2 is involved in the pathogenesis of autosomal dominant retinal degeneration in this group of patients. All the changes detected were found to be sequence variations or polymorphisms and not disease causing.

Calcium-Binding Proteins↗
PubMed1998

Genomic organization and partial duplication of the human alpha7 neuronal nicotinic acetylcholine receptor gene (CHRNA7).

The human alpha7 neuronal nicotinic acetylcholine receptor gene (HGMW-approved symbol CHRNA7) has been characterized from genomic clones. The gene is similar in structure to the chick alpha7 gene with 10 exons and conserved splice junction positions. The size of the human gene is estimated to be larger than 75 kb. A putative promoter 5' of the translation start in exon 1 has been cloned and sequenced. The promoter region lacks a TATA box and has a high GC content (77%). Consensus Sp1, AP-2, Egr-1, and CREB transcription factor binding sites appear to be conserved between bovine and human genes. The alpha7 nAChR gene was found to be partially duplicated, with both loci mapping to the chromosome 15q13 region. A yeast artificial chromosome contig was constructed over a genetic distance of 5 cM that includes both alpha7 loci and the region between them. Four novel exons are described, located in genomic clones containing the partially duplicated gene. The duplicated sequences, including the novel exons, are expressed in human brain.

Base Sequence↗
PubMed1998

Visual representations during saccadic eye movements.

In normal vision, shifts of attention are usually followed by saccadic eye movements. Neurons in extrastriate area V4 are modulated by focal attention when eye movements are withheld, but they also respond in advance of visually guided saccadic eye movements. We have examined the visual selectivity of saccade-related responses of area V4 neurons in monkeys making delayed eye movements to receptive field stimuli of varying orientation. This task did not require the monkey to attend to orientation per se but merely to foveate the receptive field stimulus. We present evidence that the presaccadic enhancement exhibited by V4 neurons, quite separate from the response at stimulus onset, is a resurgent visual representation that seems as selective as the response is when the stimulus first appears. The presaccadic enhancement appears to provide a strengthening of a decaying featural representation immediately before an eye movement is directed to visual targets. We suggest that this reactivation provides a mechanism by which a clear perception of the saccade goal can be maintained during the execution of the saccade, perhaps for the purpose of establishing continuity across eye movements.

Animals↗
PubMed1998

Further investigation of a chromosome 15 locus in schizophrenia: analysis of affected sibpairs from the NIMH Genetics Initiative.

Linkage of a neurophysiological deficit associated with schizophrenia, i.e., the failure to inhibit the auditory P50 response, was previously reported at chromosome 15q14. The marker with the highest pairwise lod score, D15S1360, was isolated from a yeast artificial chromosome containing a candidate gene, the alpha7-nicotinic acetylcholine receptor gene. In the present study, this linkage was further investigated in a subset of the NIMH Genetics Initiative schizophrenia families. These families have not been studied neurophysiologically, as were the families in the original report. Therefore, the DSMIII-R diagnosis of schizophrenia was used as the affected phenotype. Twenty families fulfilled the criteria of at least one sibpair concordant for schizophrenia, along with their two parents or another affected relative outside the nuclear family, available for genotyping. Sibpair analysis showed a significant proportion of D15S1360 alleles shared identical-by-descent (0.58; P < 0.0024). The results further support the involvement of this chromosomal locus in the genetic transmission of schizophrenia.

Chromosomes, Human, Pair 15↗
PubMed1998

DMSO produces a new subgel phase in DPPC: DSC and X-ray diffraction study.

Equilibrium phases and the kinetics of subgel phase transformation of dipalmitoylphosphatidylcholine (DPPC) hydrated with mixtures of dimethylsulfoxide (DMSO)/water have been studied using differential scanning calorimetry (DSC) and X-ray diffraction (XRD). The rate of gel-to-subgel transformation is decreased with a small increase in X, the DMSO/water mole fraction, but then speeds up and becomes faster than in pure water by X = 0.16. The DSC scans show multiple subgel peaks, some of which can be attributed to impacted domain growth. For X greater than 0.10, XRD shows that there is a new, stable subgel phase, S, which also accounts for some of the multiplicity of DSC peaks. Our electron density profiles show that the thickness of the bilayer in the S phase is greater than in the usual C subgel phase. We suggest that the S subgel phase is characterized by different headgroup ordering and smaller chain tilt angle than in the C subgel phase. Electron density profiles show that increasing X decreases the water space between bilayers in all phases, subgel, gel and fluid (L alpha). For X = 0.20, a different gel phase is also observed that may be due to subtle changes in the orientation of chain tilt first observed in partially dehydrated DMPC. The dehydrating effect of DMSO explains the results of a previous study, confirmed in this study, that increasing the concentration of DMSO raises the main transition temperature and eliminates the ripple phase.

1,2-Dipalmitoylphosphatidylcholine↗