PubMed Health⌕ Search

Biomedical subjects

T Moore

Publications and source records attributed to T Moore.

At least 37 records · Page 2Linked to original sources

Eye movements modulate visual receptive fields of V4 neurons.

The receptive field, defined as the spatiotemporal selectivity of neurons to sensory stimuli, is central to our understanding of the neuronal mechanisms of perception. However, despite the fact that eye movements are critical during normal vision, the influence of eye movements on the structure of receptive fields has never been characterized. Here, we map the receptive fields of macaque area V4 neurons during saccadic eye movements and find that receptive fields are remarkably dynamic. Specifically, before the initiation of a saccadic eye movement, receptive fields shrink and shift towards the saccade target. These spatiotemporal dynamics may enhance information processing of relevant stimuli during the scanning of a visual scene, thereby assisting the selection of saccade targets and accelerating the analysis of the visual scene during free viewing.

Animals↗

Polymorphism analysis of JRK/JH8, the human homologue of mouse jerky, and description of a rare mutation in a case of CAE evolving to JME.

Disruption of the function of the mouse jerky gene by transgene insertion causes generalized recurrent seizures reminiscent of human idiopathic generalized epilepsy (IGE). A human homologue, JRK/JH8, has been cloned, which maps to 8q24, a chromosomal region associated with several forms of IGE. JRK/JH8 is, therefore, a candidate locus for at least some forms of IGE. We report corrected cDNA sequences and extended open reading frames for the mouse jerky and human JRK/JH8 genes, which add 48 amino acids to the N-terminus of the Jerky protein and which extends the region of homology with the N-terminal DNA-binding domain of the centromere-binding protein, CENP-B. Systematic sequencing of the coding region of the extended JRK/JH8 gene identified single nucleotide polymorphisms that define three haplotypes, which were used for association studies in patients with idiopathic generalized epilepsy. We report one subject with childhood absence epilepsy (CAE) that evolved to juvenile myoclonic epilepsy (JME) that has a unique de novo mutation that results in a non-conservative amino acid change at a potential protein glycosylation site. Familial analysis supports a causal role for this mutation in the disease.

Alleles↗

Second-line chemotherapy for non-small-cell lung cancer with monthly docetaxel and weekly gemcitabine: a phase II trial.

BACKGROUND: Docetaxel and gemcitabine are active against chemotherapy-pretreated non-small-cell lung cancer (NSCLC). The purpose of this phase II study was to evaluate the efficacy and safety of monthly docetaxel combined with weekly gemcitabine in NSCLC patients failing one prior regimen. PATIENTS AND METHODS: Forty patients were enrolled. Prior chemotherapy was a platinum-based combination in 36 patients, using vinorelbine in 26 patients and etoposide in 10 patients. The other four patients had prior single agents. Tumors were refractory or resistant to front-line therapy in 80% of patients. Treatment was gemcitabine 800 mg/m2 days 1, 8, 15 and docetaxel 100 mg/m2 day 1, with cycles repeated every four weeks. RESULTS: Thirteen patients responded (32.5%; 95% confidence interval (CI): 19%-49%), including one complete and 12 partial responses. Responses were observed at all metastatic sites, with similar response frequencies in platinum-sensitive and platinum-resistant/refractory tumors. The median time to progression for responders was nine months, with two responses lasting longer than a year. Median survival was 8.1 months. Hematologic toxicities included grade 4 neutropenia in 23 patients, with 4 episodes of febrile neutropenia, grade 3-4 thrombocytopenia in 9 patients, and anemia requiring red cell transfusions in 9 patients. With the exception of asthenia, severe non-hematologic toxicities were infrequent. CONCLUSIONS: Monthly docetaxel, combined with weekly gemcitabine, is an active and safe second-line therapy for NSCLC patients.

Adult↗

Monthly docetaxel and weekly gemcitabine in metastatic breast cancer: a phase II trial.

BACKGROUND: Docetaxel and gemcitabine are active against breast cancer. The purpose of this phase II study was to evaluate the efficacy and safety of monthly docetaxel combined with weekly gemcitabine in patients with chemotherapy-pretreated metastatic breast cancer. PATIENTS AND METHODS: Thirty-nine patients were enrolled, of whom thirty had received prior chemotherapy in the adjuvant setting, seven for metastatic disease, and two for both, including prior anthracycline in 33 patients. Treatment was gemcitabine 800 mg/m2 days 1, 8, 15 and docetaxel 100 mg/M2 on day 1, with cycles repeated every four weeks. RESULTS: Response rate was 79% (95% confidence interval (CI): 63%-91%), with 2 complete and 29 partial responses. Twenty-five of the responders remained progression-free for more than six months. Median survival was 24.5 months. Delivered dose intensity of gemcitabine was lower than expected (63% of planned). The predominant hematologic toxicity was grade 4 neutropenia in 36 patients, complicated by fever in three patients. With the exception of asthenia, severe non-hematological toxicities were infrequent. CONCLUSIONS: Monthly docetaxel, combined with weekly gemcitabine, has significant but manageable hematologic toxicity. Despite frequent dose adjustments, this doublet is very active in metastatic breast cancer, producing a high proportion of durable responses associated with favorable survival.

Adult↗

Open-reading-frame sequence tags (OSTs) support the existence of at least 17,300 genes in C. elegans.

The genome sequences of Caenorhabditis elegans, Drosophila melanogaster and Arabidopsis thaliana have been predicted to contain 19,000, 13,600 and 25,500 genes, respectively. Before this information can be fully used for evolutionary and functional studies, several issues need to be addressed. First, the gene number estimates obtained in silico and not yet supported by any experimental data need to be verified. For example, it seems biologically paradoxical that C. elegans would have 50% more genes than Drosophilia. Second, intron/exon predictions need to be tested experimentally. Third, complete sets of open reading frames (ORFs), or "ORFeomes," need to be cloned into various expression vectors. To address these issues simultaneously, we have designed and applied to C. elegans the following strategy. Predicted ORFs are amplified by PCR from a highly representative cDNA library using ORF-specific primers, cloned by Gateway recombination cloning and then sequenced to generate ORF sequence tags (OSTs) as a way to verify identity and splicing. In a sample (n=1,222) of the nearly 10,000 genes predicted ab initio (that is, for which no expressed sequence tag (EST) is available so far), at least 70% were verified by OSTs. We also observed that 27% of these experimentally confirmed genes have a structure different from that predicted by GeneFinder. We now have experimental evidence that supports the existence of at least 17,300 genes in C. elegans. Hence we suggest that gene counts based primarily on ESTs may underestimate the number of genes in human and in other organisms.

Animals↗

Expression of CD34 and bcl-2 in phyllodes tumours, fibroadenomas and spindle cell lesions of the breast.

AIMS: Strong expression of CD34 and bcl-2 has been described in solitary fibrous tumours. It has been proposed that these lesions arise from long-lived mesenchymal cells. We tested the hypothesis that spindle cell lesions of the breast arise from similar mesenchymal cells in the mammary stroma. METHODS AND RESULTS: Sections of phyllodes tumours (26), fibroadenomas (15), myofibroblastomas (two), pseudoangiomatous hyperplasia (five) and myoid hamartoma (one) were stained immunohistochemically for CD34 and bcl-2. Conventional mammary carcinoma is known to be CD34-negative: we therefore stained 11 spindle cell carcinomas and one adenosquamous carcinoma. The mammary stroma, particularly around lobules, stained for CD34. All the lesions (except the carcinomas) showed spindle cell staining for CD34. There was more staining in fibroadenomas than in phyllodes tumours (especially malignant tumours). The staining in phyllodes tumours was typically patchy. In some there was increased or decreased staining adjacent to the epithelium. There were occasional spindle cells positive for bcl-2 in the normal perilobular stroma. bcl-2 was frequently expressed in spindle cells in fibroadenomas, phyllodes tumours and pseudoangiomatous hyperplasia, and rarely in the other lesions. CONCLUSIONS: The combined expression of CD34 and bcl-2 suggests that fibroadenomas, phyllodes tumours and pseudoangiomatous hyperplasia may arise from long-lived bcl-2-positive mesenchymal cells in the breast in a manner similar to that proposed for solitary fibrous tumours. The absence of CD34 staining in spindle cell carcinomas is of potential diagnostic value in the distinction from malignant phyllodes tumours in difficult cases.

Antigens, CD34↗

Paclitaxel, cisplatin, and concurrent radiation for esophageal cancer.

Paclitaxel is an active agent for adenocarcinomas and squamous cell carcinomas of the esophagus and is a radiation sensitizer. We sought to investigate the toxicity and complete response rate of paclitaxel, cisplatin, and concurrent radiation for esophageal cancer. Forty-one patients with esophageal cancer were studied, 29 with adenocarcinomas and 12 with squamous cell cancers. Twelve patients had tumor extension into the proximal stomach and/or abdominal adenopathy. Patients received paclitaxel 60 mg/m2 by 3-hour intravenous (i.v.) infusion, and cisplatin 25 mg/m2 weekly on days 1, 8, 15, and 22. Radiation was administered concurrently to a total dose of 39.60 Gy, in 1.80 Gy fractions, for 22 treatments. Patients with medical or surgical contraindications to esophagectomy received 2 additional weeks of paclitaxel with a radiation boost to 50.4 Gy. Neutropenia was the most common grade 3/4 toxicity occurring in 10 patients (24%). Only 2 patients (5%) had grade 4 esophagitis requiring parenteral nutrition. Twelve patients (29%) obtained a complete response. The 2-year progression-free and overall survival rates were 40% and 42%, respectively. Esophagitis was less severe than expected and prophylactic enteral feeding tubes were not necessary. Additional effective systemic treatments are needed to reduce the development of distant metastases.

Adenocarcinoma↗

Ankle brachial pressure index in systemic sclerosis: influence of disease subtype and anticentromere antibody.

OBJECTIVE: To test the hypothesis that patients with limited cutaneous systemic sclerosis (SSc) have a higher incidence of lower limb large vessel disease than patients with diffuse cutaneous disease, and that anticentromere antibody is a risk factor for lower limb large vessel disease. METHODS: Clinical and laboratory data from 119 patients with SSc (91 patients with limited cutaneous disease, 28 patients with diffuse cutaneous disease) who had bilateral ankle brachial pressure indices (ABPI) measured between March 1997 and January 2000 were reviewed retrospectively. RESULTS: There was no evidence of reduced ABPI in limited cutaneous disease (P=0.65), average reduction 0.01 [95% confidence interval (CI) -0.04 to +0.07]. There was some suggestion of reduced ABPI in anticentromere-positive patients (P=0.12), average reduction 0.04 (95% CI -0.01 to +0.09). CONCLUSIONS: The severity of large vessel macrovascular disease, as assessed by ABPI, is not dependent on disease subtype. Anticentromere antibody may be weakly associated with a reduction in ABPI.

Adult↗

Foot problems in patients with systemic sclerosis.

OBJECTIVES: To assess the nature of the foot problems experienced in patients with systemic sclerosis (SSc) and patient awareness of such problems. METHODS: Fifty unselected patients (42 females, eight males) with SSc were assessed by means of examination by a senior podiatrist, completion of a questionnaire detailing past and present foot problems, determination of random plasma glucose, plain X-rays of the feet, and measurement of the ankle/brachial index and of digital pulses by Doppler ultrasound. RESULTS: Eighty-six per cent of patients reported colour changes in their feet in response to temperature changes, 82% reported pain usually related to cold, 26% had suffered foot ulceration and 8% had a history of foot surgery. Podiatry assessment confirmed the presence of significant abnormalities, including ulcerations in 10%, pre-ulcerative lesions in 34%, toenail changes in 62%, callus formation in 80% and calcinosis in 18%. Forty per cent of the patients had problems with the fitting of shoes, and 19% had been provided with footwear from the hospital. Plain films of the feet demonstrated the presence of erosions in 6%, soft-tissue calcification in 17%, osteopenia in 26% and degenerative changes in 60% of cases. Ten per cent of the patients had an abnormal ankle brachial index (less than 1.0). Only 21% of the 47 patients in whom digital pulses were examined had normal pulses in all toes, and in 26% all toe pulses were absent. CONCLUSION: Although problems with the hands are well recognized in SSc, foot problems also occur in the majority of patients, and can be a cause of major disability. Care of the feet is therefore an important part of the management of SSC.

Adult↗

Overexpression of the HER-2/neu oncogene in pancreatic adenocarcinoma.

Novel systemic treatments are needed in pancreatic cancer. The authors sought to establish the frequency of overexpression of the HER-2/neu oncogene in patients with pancreatic adenocarcinoma to determine the potential role of trastuzumab (Herceptin) as a therapeutic agent in this disease. Tumor specimens from patients with pancreatic adenocarcinoma were analyzed by staining for p185HER2 protein using the DAKO immunohistochemical assay. Patients with and without HER-2/neu overexpression by immunohistochemistry were compared with respect to clinical and pathologic characteristics. HER-2/neu gene amplification was also evaluated by fluorescence in situ hybridization (FISH). Thirty-two of 154 patients (21%) had pancreatic adenocarcinoma that demonstrated HER-2/neu overexpression by immunohistochemistry. At initial diagnosis, 16% of resectable cancers, 17% of locally advanced cancers, and 26% of metastatic cancers were determined to have HER-2/neu overexpression. Three of 11 (27%) patients with HER-2/neu overexpression by immunohistochemistry had gene amplification by FISH. HER-2/neu overexpression occurs in a subset of pancreatic cancer. Evaluation of the efficacy of trastuzumab for patients with pancreatic cancer who overexpress HER-2/neu appears indicated.

Aged↗

Alveolar macrophage deactivation in murine septic peritonitis: role of interleukin 10.

Sepsis predisposes the host to a number of infectious sequelae, particularly the development of nosocomial pneumonia. Mechanisms by which sepsis results in impairment of lung antibacterial host defense have not been well defined. Alveolar macrophages (AM) represent important immune effector cells of the lung airspace. In this study, we examined the effects of cecal ligation and puncture (CLP) on murine AM function ex vivo, including the expression of proinflammatory cytokines and AM phagocytic activity. AM were harvested from mice subjected to a sham operation and CLP 24 h after laparotomy, adherence purified, and challenged with lipopolysaccharide (LPS) or left unstimulated. Both unstimulated and LPS-stimulated AM from mice subjected to CLP (CLP mice) produced significantly smaller amounts of proinflammatory cytokines tumor necrosis factor alpha and interleukin (IL-12) and C-X-C chemokines KC and macrophage inflammatory protein 2 than similarly treated AM from animals subjected to a sham operation. Furthermore, AM isolated from CLP mice displayed a marked impairment in phagocytic activity, as determined by flow cytometry, with this defect persisting to 48 h post-CLP. Induction of peritoneal sepsis syndrome resulted in a time-dependent increase in IL-10 in plasma and peritoneal fluid. Interestingly, the impairment in AM proinflammatory-cytokine production and phagocytic activity observed in AM from CLP mice was partially reversed by the in vivo neutralization of IL-10 prior to AM harvest. These observations suggest that abdominal sepsis syndrome results in significant impairment in AM effector cell function, which is mediated, in part, by sepsis-induced expression of IL-10.

Animals↗

Evaluation of liquid handling conditions in microplates.

Liquid handling in higher density microplates (e.g., 1536-well microplates) for more efficient drug screening necessitates carefully selected and optimized parameters. The quality of a liquid handling procedure is dependent on the carryover rate of residual liquids during the pipetting process, the mixing behavior in the wells, foam and bubble formation, and evaporation. We compared and optimized these parameters in 96-, 384-, and 1536-well microplates, and herein we critically evaluate the performance of the CyBi-Well 96/384/1536 automated micropipetting device, which formed the basis of our evaluation studies.

Drug Contamination↗

Southern analysis using methyl-sensitive restriction enzymes.

Methylation of the cytosine base in cytosine-guanine (CG) dinucleotides of genomic DNA is likely to be one of the primary epigenetic "imprints" that results in parental allele-specific expression of certain mammalian genes (1). Despite the increasing popularity of bisulphite sequencing (2), ligationmediated polymerase chain reaction (PCR) (3), the availability of antibodies to 5-methylcytosine ((5m)CG) (4), and more recent developments in DNA array technology (5), Southern analysis using methyl-sensitive DNA restriction enzymes remains one of the more popular methods for the detection and analysis of mammalian DNA methylation. However, it has two significant disadvantages. First, relatively large amounts of genomic DNA are required for Southern blotting, thereby reducing its usefulness in the study of DNA methylation in the female germline and preimplantation embryos. Second, the analysis is limited to CGs that occur in a DNA sequence context that is recognized by a methyl-sensitive restriction enzyme. However, despite these drawbacks, the fact that the technique is still widely used is testament to its robustness, reproducibility, and relative simplicity.

Animals↗

Genetic conflict, genomic imprinting and establishment of the epigenotype in relation to growth.

Genomic imprinting is the process that differentially modifies the parental alleles at certain genetic loci in the parental germlines. Such modifications of DNA and chromatin are somatically heritable and cause unequal expression of the parental alleles during subsequent development. In mammals, imprinted genes encode a relatively small number of functionally heterogeneous proteins. Nevertheless, imprinted genes exert important effects, primarily on fetal development, and their deregulation is implicated in a variety of pathologies including sporadic, inherited and induced growth disorders. Imprinted loci show several unusual structural and functional characteristics that may be related to mechanistic aspects of mono-allelic expression or to modes of evolution of imprinted genetic loci. Typically, imprinted genes are clustered in certain genomic regions and have relatively reduced intronic DNA content relative to non-imprinted genes. In addition, their regulatory regions frequently contain a combination of features including tandem repeats associated with differentially methylated CpG islands and overlapping transcription of coding or non-coding RNAs. The evolution of imprinting can be understood as the stable outcome of sexual selection acting differently on the parental alleles of genes that influence parental investment in offspring. Consistent with this explanation, imprinted genes are expressed predominantly during embryonic and postnatal development in mammals and in the developing endosperm of plants, and maternal or paternal expression at imprinted loci is associated with reduced or increased parental investment, respectively. Such selective forces have implications for understanding mechanistic aspects of genome reprogramming in the early mammalian embryo.

Animals↗

The impact of a clinic-based literacy intervention on language development in inner-city preschool children.

OBJECTIVE: To determine the effect of a clinic-based literacy intervention on the language development of preschool children. METHODS: A convenience sample of families presenting to 2 urban pediatric clinics for well-child care met the following criteria: the family was Latino or black and English- or Spanish-speaking; the child was 2 to 5.9 years old, with no neurodevelopmental disability, at a gestational age of 34 weeks or more, and not attending kindergarten. Participants at the first clinic (intervention group) were exposed to a literacy support program, based on Reach Out and Read (ROR), during the previous 3 years. At the second clinic (comparison group), a similar program started 3 months before the study. Parent-child reading activities were measured using the READ Subscale of the StimQ. Language development was measured using the One-Word Expressive and Receptive Picture Vocabulary Tests, and was performed in the child's primary language. RESULTS: A total of 122 study participants (49 interventions and 73 comparisons) met inclusion criteria and completed all measures. Intervention and comparison families were similar for most sociodemographic variables. Intervention families reported reading together with their children approximately 1 more day per week. Intensity of exposure to ROR (measured by total number of contacts with the program) was associated with increased parent-child reading activities, as measured by the StimQ-Read Subscale (r = 0.20). Intervention children had higher receptive language (mean: 94.5 vs 84.8) and expressive language (mean: 84.3 vs 81.6). After adjusting for potential confounders in a multiple regression analysis, intervention status was associated with an 8.6-point increase (95% confidence interval [CI]: 3.3, 14.0) in receptive language (semipartial correlation [SR]coefficient = 0.27), and a 4.3-point increase (95% CI: 0.04, 8.6) in expressive language (SR = 0.17). In a similar multiple regression, each contact with ROR was associated with an adjusted mean 0.4-point increase (95% CI: 0.1, 0.6) in receptive score, and an adjusted mean 0.21-point increase (95% CI: 0. 02, 0.4) in expressive score. CONCLUSIONS: ROR is an important intervention, promoting parental literacy support and enhancing language development in impoverished preschool children. Integration of literacy promoting interventions such as these into routine pediatric health care for underserved populations can be recommended.

Chi-Square Distribution↗

p53 mutations do not predict response to paclitaxel in metastatic nonsmall cell lung carcinoma.

BACKGROUND: In vitro data and animal studies suggest that paclitaxel may have a unique ability to activate tumor cell apoptosis in the absence of wild-type p53 function. The authors previously demonstrated that response to paclitaxel and concurrent radiation was not affected by p53 mutations in nonsmall cell lung carcinoma (NSCLC). We sought to determine whether p53 mutations affect response to paclitaxel alone in patients with metastatic NSCLC. METHODS: Twenty-five patients with metastatic NSCLC who participated in Brown University Oncology Group protocols utilizing single-agent weekly paclitaxel had tumor tissue that was adequate for p53 analysis. Tumor tissue was evaluated for p53 gene mutations in exons 5 through 8 by single-strand conformation polymorphism analysis. Mutations were confirmed by direct sequencing of altered mobility polymerase chain reaction products. RESULTS: Mutations in p53 were found in 8 of 25 patients (32%). The response rates of 75% for patients with tumors with p53 mutations and 47% for patients with wild-type p53 do not differ significantly (P = 0.12). The 1-year survival rates for patients with and without p53 mutation after treatment with weekly paclitaxel were 63% (95% confidence interval [CI], 31-100%) and 53% (95% CI, 33-86%), respectively. CONCLUSIONS: p53 mutations do not adversely affect response to paclitaxel as a single agent in metastatic NSCLC. These results provide clinical support for in vitro observations that paclitaxel can bypass mutant p53 and lead to tumor cell death by alternate pathway(s). Paclitaxel should be considered as a component of treatment for patients with metastatic NSCLC with tumors that have p53 mutations.

Antineoplastic Agents, Phytogenic↗

Experimental investigation and mathematical modeling of Pluronic F127 gel dissolution: drug release in stirred systems.

We have examined the dissolution of Pluronic F127 gels in a USP dissolution apparatus under stirred conditions, and simultaneously monitored the release of model drugs from these gels. The drugs selected were propranolol HCl, metronidazole and cephalexin. Our results show that drug release is zero-order and is controlled by the dissolution of the gel for all the drugs, under various conditions of temperature, F127 concentration, drug concentration, and for stirring speeds between 20 and 80 rpm. The addition of inorganic salts has no significant effect on dissolution rate or drug release. Increasing F127 concentration in the gel decreases gel dissolution and drug release rates. We have developed a predictive mathematical model based on the assumption that uptake of water into the gel and subsequent disentanglement of F127 micelles control gel dissolution. There is good agreement between experimental results and model predictions for stirring speeds above 20 rpm. As stirring speed is decreased to 20 rpm and below, there are discrepancies between actual and predicted values, presumably due to a significant diffusion component that contributes to drug release.

Algorithms↗