51
|
Adams WM, Dueland RT, Daniels R, Fialkowski JP, Nordheim EV. Comparison of two palpation, four radiographic and three ultrasound methods for early detection of mild to moderate canine hip dysplasia. Vet Radiol Ultrasound 2000; 41:484-90. [PMID: 11130786 DOI: 10.1111/j.1740-8261.2000.tb01875.x] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Hip joint laxity was evaluated in Golden Retriever (n = 60), Labrador Retriever (n = 23), and Labrador/Golden Retriever mix (n = 24) puppies. Ortolani and Bardens maneuvers, four radiographic measurement indices and three dynamic ultrasonographic measurements were used. Each puppy was evaluated twice; at 6.5 to 9 and 43 to 79 weeks of age. These nine methods were compared for accuracy in predicting the development of canine hip dysplasia with or without degenerative joint disease by a median age of 16 months. The Bardens maneuver was a significant predictor of canine hip dysplasia/+/-degenerative joint disease for Golden Retriever puppies, however, it was not a reliable predictor for the other two breeds. Norberg angle measurements taken with femurs in a neutral position with hips distracted (PennHip position) was a significant predictor of degenerative joint disease in two breeds, but not in Golden Retriever puppies. Ultrasound measurement was a reliable predictor of hip canine hip dysplasia/+/-degenerative joint disease for Labrador/Golden Retriever mix puppies, but was not reliable for the other two breeds. Palpation, radiographic, and ultrasonographic methods of evaluating hip joint laxity in puppies at 6.5 to 9 weeks of age were not consistently reliable for all three breeds in predicting hip dysplasia with or without degenerative joint disease at one year of age. A strong association was found between Norberg angle and degenerative joint disease occurrence, as well as between distraction index (PennHip) and degenerative joint disease occurrence when measured at 52 to 79 weeks of age, but not when measured at 6.5 to 9 weeks of age in these breeds. These results emphasize the difficulty of early detection of mild hip dysplasia in the dog.
Collapse
|
52
|
Daniels R, Hall V, Trounson AO. Analysis of gene transcription in bovine nuclear transfer embryos reconstructed with granulosa cell nuclei. Biol Reprod 2000; 63:1034-40. [PMID: 10993824 DOI: 10.1095/biolreprod63.4.1034] [Citation(s) in RCA: 208] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
The low efficiency of animal production using somatic cell nuclear transfer procedures is considered to be the result of an incomplete reprogramming of the donor somatic cell nucleus, which leads to a lack of, or abnormal expression of developmentally important genes. However, our current understanding of the process of somatic cell nuclear reprogramming and its effect on gene expression is limited. In this study, we compare the transcription patterns of six developmentally important genes, Oct4, IL6, FGF2, FGF4, FGFr2, and gp130 in single in vitro fertilized (IVF) and nuclear transfer embryos reconstructed using granulosa cells for the donor nuclei. Similar patterns of transcription were detected for Oct4, FGF2, and gp130 in IVF and nuclear transfer embryos during the preimplantation stages of development. However, a number of morula- and blastocyst-stage embryos derived from nuclear transfer procedures showed abnormal transcription of IL6, FGF4, and FGFr2. Previous studies have demonstrated that these three genes play an important role in implantation, early postimplantation development, or both in the mouse. Therefore, the aberrant transcription patterns detected in nuclear transfer embryos may lead to a reduction in embryo viability.
Collapse
|
53
|
Wollenweber C, Makievski A, Miller R, Daniels R. Adsorption of hydroxypropyl methylcellulose at the liquid/liquid interface and the effect on emulsion stability. Colloids Surf A Physicochem Eng Asp 2000. [DOI: 10.1016/s0927-7757(00)00569-0] [Citation(s) in RCA: 87] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
|
54
|
Cornum RL, Morey AF, Harris R, Gresham V, Daniels R, Knight RW, Beall D, Pusateri A, Holcomb J, Macphee M. Does the absorbable fibrin adhesive bandage facilitate partial nephrectomy? J Urol 2000; 164:864-7. [PMID: 10953169 DOI: 10.1097/00005392-200009010-00063] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE To evaluate the ability of the absorbable fibrin adhesive bandage (AFAB), a prototype product comprising lyophilized fibrinogen and thrombin on a VicrylTM mesh backing, to seal the collecting system and control bleeding after partial nephrectomy. MATERIALS AND METHODS Growing female pigs (n = 18) underwent left nephrectomy and a 40% (by length) right lower pole partial nephrectomy. One of three treatments was immediately applied: Conventional-closure of the collecting system, ligation of visible segmental vessels, application of SurgicelTM with bolstering sutures to the renal capsule; AFAB-application of up to two 4 x 4-inch AFABs held under pressure for 60 seconds; Placebo-application of a hemostatically inert VicrylTM bandage, visually identical to the AFAB. Blood loss and ischemic and total operative times were recorded, and abdominal computerized tomography (CT) was performed on postoperative day 6. Animals were sacrificed at 6 weeks to evaluate the remaining renal mass histologically. RESULTS Compared with conventional therapy, use of the AFAB resulted in significantly less bleeding (13 versus 68 ml., p <0.001) and lower operative (7.2 versus 16.3 minutes, p <0.001) and ischemic times (3.4 versus 7.8 minutes, p <0.001). Estimated blood loss in the placebo bandage group was dramatically higher (357 ml., p <0.001). Postoperative CT and histological sectioning suggested that the AFAB produces a stable, durable clot and that healing is at least as successful as with conventional treatment. CONCLUSION Use of the AFAB facilitated performance of partial nephrectomy by reducing blood loss and ischemic and total operative times. The AFAB appears equivalent to conventional surgery in its ability to seal the collecting system.
Collapse
|
55
|
Gigant B, Barbey-Martin C, Bizebard T, Fleury D, Daniels R, Skehel JJ, Knossow M. A neutralizing antibody Fab-influenza haemagglutinin complex with an unprecedented 2:1 stoichiometry: characterization and crystallization. ACTA CRYSTALLOGRAPHICA SECTION D: BIOLOGICAL CRYSTALLOGRAPHY 2000; 56:1067-9. [PMID: 10944356 DOI: 10.1107/s0907444900006776] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2000] [Accepted: 05/03/2000] [Indexed: 11/10/2022]
Abstract
The haemagglutinin HA is a trimer of identical subunits and is the more abundant viral surface glycoprotein of the influenza virus. It is the target of antibodies that neutralize viral infectivity. Antibodies that bind to HA with 3:1 and 1:1 stoichiometries have been identified. Here, an antibody whose Fab binds to HA with an unprecedented 2:1 Fab:HA stoichiometry is characterized. The complex has been crystallized and synchrotron data to 3.5 A resolution have been collected. Molecular replacement confirms the stoichiometry of the complex.
Collapse
|
56
|
Rigby P, Foulks E, Riddick F, Braun K, Daniels R, Hilton C. The Medical Education Commission report at the turn of then new millennium 2000. THE JOURNAL OF THE LOUISIANA STATE MEDICAL SOCIETY : OFFICIAL ORGAN OF THE LOUISIANA STATE MEDICAL SOCIETY 2000; 152:386-91. [PMID: 11011524] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
The State of Louisiana Medical Education Commission was formed by Act 3 of the 1997 Louisiana Legislature. The members are appointed by the Louisiana State University Health Sciences Center, Tulane University Medical Center, and Alton Ochsner Medical Foundation and report to and advise the Department of Health and Hospitals (DHH). This summation from the Medical Education Committee is designed to answer three questions. First, how does the State of Louisiana compare nationally in the renewal of physician supply and capability? Second, what are the current status and trends of graduate medical education in Louisiana? Third, what recommendations are proposed to continue and improve the important relationship between the State public hospitals and educational programs? The State of Louisiana has participated proportionately relative to population in the growth and progress of medical education in this last century and compares favorably with other states and the nation. Louisiana exceeds national averages in the increase of primary care residency programs and positions and in the retention of trainees in practice sites in the State. The three-year trends in total number of graduate medical education filled positions has been consistent with only 0.4% change, with primary care showing an overall increase of 9%, reflecting increases in Family Medicine (56%) and Medicine/Pediatrics (41%).
Collapse
|
57
|
Hooper JD, Bowen N, Marshall H, Cullen LM, Sood R, Daniels R, Stuttgen MA, Normyle JF, Higgs DR, Kastner DL, Ogbourne SM, Pera MF, Jazwinska EC, Antalis TM. Localization, expression and genomic structure of the gene encoding the human serine protease testisin. BIOCHIMICA ET BIOPHYSICA ACTA 2000; 1492:63-71. [PMID: 11004480 DOI: 10.1016/s0167-4781(00)00071-3] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Testisin is a recently identified human serine protease expressed by premeiotic testicular germ cells and is a candidate tumor suppressor for testicular cancer. Here, we report the characterization of the gene encoding testisin, designated PRSS21, and its localization on the short arm of human chromosome 16 (16p13.3) between the microsatellite marker D16S246 and the radiation hybrid breakpoint CY23HA. We have further refined the localization to cosmid 406D6 in this interval and have established that the gene is approximately 4. 5 kb in length, and contains six exons and five intervening introns. The structure of PRSS21 is very similar to the human prostasin gene (PRSS8) which maps nearby on 16p11.2, suggesting that these genes may have evolved through gene duplication. Sequence analysis showed that the two known isoforms of testisin are generated by alternative pre-mRNA splicing. A major transcription initiation site was identified 97 nucleotides upstream of the testisin translation start and conforms to a consensus initiator element. The region surrounding the transcription initiation site lacks a TATA consensus sequence, but contains a CCAAT sequence and includes a CpG island. The 5'-flanking region contains several consensus response elements including Sp1, AP1 and several testis-specific elements. Analysis of testisin gene expression in tumor cell lines shows that testisin is not expressed in testicular tumor cells but is aberrantly expressed in some tumor cell lines of non-testis origin. These data provide the basis for identifying potential genetic alterations of PRSS21 that may underlie both testicular abnormalities and tumorigenesis.
Collapse
|
58
|
Schulz MB, Daniels R. Hydroxypropylmethylcellulose (HPMC) as emulsifier for submicron emulsions: influence of molecular weight and substitution type on the droplet size after high-pressure homogenization. Eur J Pharm Biopharm 2000; 49:231-6. [PMID: 10799814 DOI: 10.1016/s0939-6411(00)00069-2] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Hydroxypropylmethylcellulose (HPMC) is a known emulsifier as well as a common viscosity enhancer in eye drops. Therefore, HPMC stabilized emulsions appear as interesting drug carriers for ophthalmic use and as a suitable treatment of dry eye syndrome. Since submicron emulsions are known to have an improved drug delivery, attempts were made to reduce the emulsion's droplet size by high-pressure homogenization. Droplet size was dependent on the homogenization pressure and the polymer content. Differences were found between emulsions stabilized with higher and lower molecular weight HPMC. Smaller droplet sizes were obtained with the shorter chained HPMC. No considerable influence of the substitution type was observed.
Collapse
|
59
|
Jinks AM, Daniels R. Workplace health concerns: a focus group study. JOURNAL OF MANAGEMENT IN MEDICINE 2000; 13:95-104. [PMID: 10747454 DOI: 10.1108/02689239910269644] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Addresses the workplace health concerns of employees at an Acute Hospital Trust. The research conducted utilised a focus group methodology to investigate the health concerns of multidisciplinary groups of health care workers (n = 27). The findings indicate that the concern for the majority was workplace stress. Stressors that were identified as important to the groups were for example, the nature of the work they were undertaking, staffing levels, volume of the work, management styles and their work environments. Health promotion and prevention topics such as motivation and health status, smoking, alcohol and drug misuse, nutrition and weight control and physical exercise were seen of subsidiary concern. Limitations of the study are given. Future research in the subject area is identified.
Collapse
|
60
|
Schepper K, Ulmer H, Göpel W, Daniels R. Performance of GC-MS and MOSES II, a hybrid modular sensor system, for the quantitative detection of the evaporation of the insect repellent N,N-diethyl-m-toluamide from two different matrices. DIE PHARMAZIE 2000; 55:97-101. [PMID: 10723766] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
Abstract
The purpose of this work was to determine the evaporated amount of N,N-diethyl-m-toluamide (DEET), a commonly used insect repellent, from two different matrices medium chain triglycerides (MCT) and Polyethylene glycol 400 (PEG), with GC with mass sensitive detection (GC-MS) and a hybrid modular sensor system (MOSES II). Thus, the binary mixtures are equilibrated at 80 degrees C for 45 min and then an aliquot of this headspace is analyzed by GC-MS and a sensory system consisting of an array of eight metal oxide sensors and eight quartz crystal microbalances. Both analytical methods allow a sensitive detection of even small amounts of DEET in the headspace from binary mixtures with the MCT or PEG, respectively. The two additives are found to be very different concerning their behavior to the vapor phase; i.e., the lipophilic (MCT) delivers an almost constant headspace of DEET, while the hydrophilic matrix PEG releases smaller amounts of DEET, which continuously decrease when a multiple headspace extraction is performed. Furthermore, the results reveal that both analytical methods lead to comparable results with the MCT/DEET mixtures whereas differences were seen with mixtures containing PEG. This can be attributed to the interaction of volatile portions of PEG with the sensors of the MOSES II.
Collapse
|
61
|
Daniels R. Book Review. Eur J Pharm Biopharm 2000. [DOI: 10.1016/s0939-6411(99)00044-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
|
62
|
Carl S, Daniels R, Iafrate AJ, Easterbrook P, Greenough TC, Skowronski J, Kirchhoff F. Partial "repair" of defective NEF genes in a long-term nonprogressor with human immunodeficiency virus type 1 infection. J Infect Dis 2000; 181:132-40. [PMID: 10608759 DOI: 10.1086/315187] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
A 36-bp deletion close to the 5' end of NEF that impaired Nef function was found in a long-term nonprogressor with human immunodeficiency virus type 1 (HIV-1) infection. Forms containing an adjacent duplication of 33 bp were also frequently observed. The duplication showed no homology to the deleted region but restored the overall length of the first variable loop of Nef. NEF alleles carrying the duplication were active in class I major histocompatibility complex (MHC-I) down-modulation and enhancement of virus infectivity. However, they showed little activity in CD4 down-regulation and were unable to stimulate viral replication in human peripheral blood mononuclear cells. Our study indicates that the enhancement of virion infectivity and the stimulation of HIV-1 replication in lymphocytes are distinct functions of Nef. Our findings also illustrate the capacity for repair of attenuating deletions in HIV-1 infection and suggest that a selective pressure for Nef-mediated MHC-I down-modulation and/or enhancement of virion infectivity exists.
Collapse
|
63
|
Oades RD, Daniels R. Subclinical polydipsia and polyuria in young patients with schizophrenia or obsessive-compulsive disorder vs normal controls. Prog Neuropsychopharmacol Biol Psychiatry 1999; 23:1329-44. [PMID: 10631761 DOI: 10.1016/s0278-5846(99)00069-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
1. Increased water intake and output is more common among psychiatric patients, especially those with schizophrenia, than in the general population. Animal studies suggest that polydipsia and polyuria derive, in part, from dopamine dysregulation. Stimulated by these observations this study sought to elucidate relationships among water homeostasis, monoamine metabolism, and electrolyte excretion in schizophrenic patients with and without paranoid hallucinatory symptoms (PH vs. NP), thought to reflect hyper- and hypo-dopaminergic states respectively, and to compare these with those shown by patients with obsessive compulsive disorder (OCD). 2. 24 hr-urine samples for electrolyte, monoamine and metabolite measures were taken from 14 schizophrenic patients with PH symptoms, 13 with predominantly nonparanoid (NP) symptoms, 11 OCD patients and 27 healthy controls (matched for age, weight and creatinine production). Water intake and serum electrolytes was sampled during psychological testing. 3. PH patients drank 2-3 times more than the others in a 3-4 hr test, yet 24 hr-urinary volumes were 75% larger in both PH and NP patients than in the two comparison groups. 4. Daily potassium excretion was a bit higher in PH patients, but concentrations of sodium, potassium and phosphate tended to be lower in PH and NP patients than in the others. 5. Positive associations of electrolyte with homovanillic acid excretion were consistent across groups and not directly related to medication. But associations of electrolyte excretion with noradrenergic activity in controls were absent in psychotic patients and associations with serotonin in OCD patients were absent in the other groups. 6. Increased water intake and output in PH patients along with the disturbed association with noradrenergic metabolism are consistent with altered autonomic activity in these patients. 7. The independence of measures of water homeostasis from dopaminergic medication indicates that the associations in clinically responding PH patients of polydipsia with DA function (decreased DA levels) may be pertinent to this subgroup but not to schizophrenia in general.
Collapse
|
64
|
Vella C, Gregory J, Bristow R, Troop M, Easterbrook P, Zheng N, Daniels R. Isolation of HIV type 1 from long-term nonprogressors in Herpesvirus saimiri-immortalized T cells. AIDS Res Hum Retroviruses 1999; 15:1145-7. [PMID: 10461835 DOI: 10.1089/088922299310449] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
|
65
|
Huntriss J, Daniels R, Bolton V, Monk M. Imprinted expression of SNRPN in human preimplantation embryos. Am J Hum Genet 1998; 63:1009-14. [PMID: 9758597 PMCID: PMC1377472 DOI: 10.1086/302039] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
Prader-Willi syndrome (PWS) and Angelman syndrome (AS) are two clinically distinct neurogenetic disorders arising from a loss of expression of imprinted genes within the human chromosome region 15q11-q13. Recent evidence suggests that the SNRPN gene, which is defective in PWS, plays a central role in the imprinting-center regulation of the PWS/AS region. To increase our understanding of the regulation of expression of this imprinted gene, we have developed single-cell-sensitive procedures for the analysis of expression of the SNRPN gene during early human development. Transcripts of SNRPN were detected in human oocytes and at all stages of preimplantation development analyzed. Using embryos heterozygous for a polymorphism within the SNRPN gene, we showed that monoallelic expression from the paternal allele occurs by the 4-cell stage. Thus, the imprinting epigenetic information inherited in the gametes is recognized already in the preimplantation embryo. The demonstration of monoallelic expression in embryos means that efficient preimplantation diagnosis of PWS may be made by analysis for the presence or absence of SNRPN mRNA.
Collapse
|
66
|
Oades RD, Daniels R, Rascher W. Plasma neuropeptide-Y levels, monoamine metabolism, electrolyte excretion and drinking behavior in children with attention-deficit hyperactivity disorder. Psychiatry Res 1998; 80:177-86. [PMID: 9754697 DOI: 10.1016/s0165-1781(98)00064-x] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Against a background of (a) increased drinking behavior in children with attention-deficit hyperactivity disorder (ADHD); (b) the parallel between some behaviors associated with ADHD and hypertension; (c) the use of the spontaneously hypertensive rat as a model for ADHD; and (d) similarities in the changes of neuropeptide Y (NPY) and catecholamine in studies of hypertension and drinking, NPY, catecholamines and electrolyte balance were compared in the plasma and urine of healthy children and those with ADHD. Drinking was monitored during 3 h of neuropsychological tests over 2 days in 14 ADHD and nine healthy children. Patients drank four times as much water and showed twice the levels of NPY found in controls. In controls there were positive and in patients there were negative relationships for NPY with drinking and restless behavior. Patients' plasma levels of norepinephrine (NE) and epinephrine were slightly elevated, but urinary levels of NE and the serotonin metabolite were markedly increased. Urinary excretion rates for sodium (not potassium), phosphate and especially calcium were decreased in patients even after covarying for less urine production in the ADHD group. NPY levels were inversely related to calcium excretion and drinking was inversely related to circulating sodium. Increases of drinking and circulating NPY in ADHD children and decreased electrolyte excretion may reflect a common disturbance in metabolic homeostasis.
Collapse
|
67
|
Daniels R, Adjaye J, Bolton V, Monk M. Detection of a novel splice variant of the hypoxanthine-guanine phosphoribosyl transferase gene in human oocytes and preimplantation embryos: implications for a RT-PCR-based preimplantation diagnosis of Lesch-Nyhan syndrome. Mol Hum Reprod 1998; 4:785-9. [PMID: 9733436 DOI: 10.1093/molehr/4.8.785] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
We have detected a novel splice variant of the hypoxanthine-guanine phosphoribosyl transferase (HPRT) gene in two human oocytes and four preimplantation embryos from the 4-cell to the 8-cell stage of development. The novel HPRT transcript lacks exons 4, 5 and 6 of the normal HPRT gene. The same parental origin for the two oocytes and two of the preimplantation embryos, in which the alternatively spliced transcript was detected, might suggest that the alternative splicing is influenced by genetic background. Mutations in the HPRT gene which cause alternative mRNA splicing are implicated in Lesch-Nyhan syndrome. However, the relatively high frequency of detection of this novel HPRT transcript described here (6/109 oocytes and preimplantation embryos) suggests that it is not involved in Lesch-Nyhan syndrome. It is probable that the alternative HPRT transcript is derived from the aberrant splicing of a small percentage of the total mRNA produced from normal HPRT alleles. The presence of this alternative transcript in human preimplantation embryos may complicate an reverse transcription-polymerase chain reaction-based preimplantation diagnosis of Lesch-Nyhan syndrome.
Collapse
|
68
|
Adjaye J, Daniels R, Monk M. The construction of cDNA libraries from human single preimplantation embryos and their use in the study of gene expression during development. J Assist Reprod Genet 1998; 15:344-8. [PMID: 9604772 PMCID: PMC3454752 DOI: 10.1023/a:1022565115741] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
PURPOSE The construction and application of polymerase chain reaction (PCR)-based cDNA libraries from unfertilized human oocytes and single preimplantation-stage embryos are described. The purpose of these studies is to provide a readily available resource for the study of gene expression during human preimplantation development. METHODS Rapid, reproducible, and efficient procedures for the construction of PCR-based cDNA libraries from fewer than 10 cells were first developed in small populations of fibroblast cells. We then constructed cDNA libraries from eight unfertilized oocytes and single two-cell, -4-cell, -7-cell, and blastocyst-stage embryos. Differential display PCR using the libraries as template allows the analysis of stage-specific expression of embryonic genes. Genomic libraries are also prepared from parental samples (cumulus cells and sperm) corresponding to the individual embryo generating the cDNA library. RESULTS The complexities (between 10(5) and 10(6) clones) of the human embryo libraries indicate that they may represent the entire active gene population at these early stages of human development. Nucleotide sequence analyses of random clones showed the presence of a variety of transcripts, such as the human transposable element. LINE-1, Alu repeat sequences, housekeeping genes, and tissue-specific genes, (e.g., alpha-globin, FMR-1, and interleukin-10). Also present at the expected frequency are the ubiquitous cytoskeletal elements, beta-actin, keratin-18, and alpha-tubulin. In addition to cDNAs corresponding to known expressed sequence tags (ESTs) in the GenBank and dbEST databases, a high proportion of novel sequences was also detected. Several cDNAs were detected only at specific stages of preimplantation development by the differential display analysis. CONCLUSIONS PCR-based cDNA libraries from single human preimplantation embryos provide a new and important resource for the identification and study of novel genes or gene families. As such, they will increase our basic understanding of the molecular control of human development. In the clinical context, the libraries identify the time of onset of specific genes, and hence the diseases resulting from mutation of these genes, and provide information about new methods of preimplantation diagnosis. The molecular analysis of early gene transcription in human embryogenesis may be expected to lead to advances in contraception, assisted reproduction, and preimplantation genetic diagnosis.
Collapse
|
69
|
Abstract
In this paper, the construction, evaluation, and application of cDNA libraries from eight unfertilized oocytes and single four-cell-, seven-cell-, and blastocyst-stage embryos are described. Rapid, reproducible, and efficient procedures for the construction of PCR-based cDNA libraries from fewer than 10 cells were first developed in small populations of fibroblast cells. The human embryo libraries display complexities sufficient (between 10(5) and 10(6) clones) to represent the entire active gene population at these early stages of human development. The ubiquitous cytoskeletal elements, beta-actin, keratin-18, and alpha-tubulin, were detected at the expected frequency. Sequencing of consecutively picked random clones, without selection, showed the presence of a variety of sequences, such as the human transposable element, LINE-1 and Alu repeat sequences, housekeeping genes, and tissue-specific genes, such as alpha-globin and FMR-1. In addition to cDNAs corresponding to known ESTs (expressed sequence tags) in the GenBank and dbEST databases, a high proportion of novel sequences were detected. Applications of the libraries to several areas of interest, such as expression of CpG-island-containing "tissue-specific" genes, developmental genes expressed in a stage-specific manner, and a search for monoallelic expression of imprinted genes, are described. The libraries are a valuable resource for the study of gene expression during human preimplantation development and obviate the need for research on the human embryos themselves.
Collapse
|
70
|
Baker R, Wijmans J, Athayde A, Daniels R, Ly J, Le M. The effect of concentration polarization on the separation of volatile organic compounds from water by pervaporation. J Memb Sci 1997. [DOI: 10.1016/s0376-7388(97)00189-0] [Citation(s) in RCA: 88] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
|
71
|
Daniels R, Lowell S, Bolton V, Monk M. Transcription of tissue-specific genes in human preimplantation embryos. Hum Reprod 1997; 12:2251-6. [PMID: 9402290 DOI: 10.1093/humrep/12.10.2251] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
We have recently detected de-novo transcripts of the predominantly muscle-specific myotonin protein kinase gene in human preimplantation embryos from the 1-cell to the 4-cell stages. Others have shown de-novo transcripts of the Y-linked genes, ZFY and SRY, in the 1-cell zygote. In order to assess the significance of early transcription of these predominantly tissue-specific genes in preimplantation development, we have analysed individual human oocytes and preimplantation embryos for the presence of transcripts of two further tissue-specific genes, alpha-globin and beta-globin, and two house-keeping genes, HPRT and APRT. Reverse transcriptase polymerase chain reaction assays were developed to the required single cell sensitivity, using human red blood cells and fibroblasts, prior to their application to human oocytes and embryos. As expected, transcripts of the house-keeping genes, HPRT and APRT, were detected at all stages of preimplantation development. Transcripts of 'tissue-specific' alpha-globin were readily detected in preimplantation embryos from the 1-cell stage. However, transcripts of beta-globin were detected only rarely (in only one of the 11 embryos analysed). This difference may be due to the fact that alpha-globin contains a CpG island. A survey of the data on gene expression in early human development suggests that CpG-island-containing genes may be expressed in preimplantation embryos. Expression of these genes in gametes and early embryos may be involved in the survival of CpG islands in evolution.
Collapse
|
72
|
Daniels R, Zuccotti M, Kinis T, Serhal P, Monk M. XIST expression in human oocytes and preimplantation embryos. Am J Hum Genet 1997; 61:33-9. [PMID: 9245982 PMCID: PMC1715845 DOI: 10.1086/513892] [Citation(s) in RCA: 76] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
During mouse preimplantation development, the exclusive expression of the Xist gene from the paternally inherited allele is thought to play a role in the inactivation of the paternally inherited X chromosome in the extra-embryonic cell lineages of the developing female embryo. Recently, inactivation of the paternally inherited X chromosome has also been shown to occur in the extraembryonic cell lineages of the human female conceptus. In this paper, we determine whether the pattern of XIST expression in human preimplantation embryos is similarly correlated with paternal X inactivation. We developed procedures sensitive to the single cell, for the simultaneous analysis of XIST and HPRT expression and of sexing, initially using human fibroblast cells. Application of these procedures to human cleavage-stage embryos derived by in vitro fertilization revealed a pattern of XIST expression different from that in the mouse. Transcripts of the XIST gene were detected as early as the 1-cell zygote and, with increasing efficiency, through to the 8-cell stage of preimplantation development. In addition, transcripts of XIST were detected in both male (hence from the maternally inherited allele) and female preimplantation embryos. This pattern of expression is not consistent with a role for the early expression of the XIST gene in the choice of paternal X inactivation in the extraembryonic cell lineages of the developing human embryo.
Collapse
|
73
|
Daniels R, Zuccotti M, Monk M. O-045. Gene transcription in human preimplantation embryos. Hum Reprod 1997. [DOI: 10.1093/humrep/12.suppl_2.21-b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
|
74
|
Adjaye J, Daniels R, Bolton V, Monk M. O-046. cDNA libraries from single human preimplantation embryos. Hum Reprod 1997. [DOI: 10.1093/humrep/12.suppl_2.22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
|
75
|
Vella C, Fickenscher H, Atkins C, Penny M, Daniels R. Herpesvirus saimiri-immortalized human T-cells support long-term, high titred replication of human immunodeficiency virus types 1 and 2. J Gen Virol 1997; 78 ( Pt 6):1405-9. [PMID: 9191937 DOI: 10.1099/0022-1317-78-6-1405] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Herpesvirus saimiri strain C488 transforms human CD4+ T-lymphocytes to continuous interleukin-2-dependent growth. Unlike human T-cell lines derived from tumours or those transformed by human T-lymphotropic virus 1, herpesvirus saimiri-immortalized T-cells (HVS T-cells) retain many functions of primary activated T-lymphocytes. We have characterized the course of human immunodeficiency virus types 1 and 2 (HIV-1/-2) infection in three HVS T-cell lines. Our results confirm that HVS T-cells are highly permissive to both HIV-1/-2 prototype viruses and to poorly replicating HIV-2 strains of restricted cell tropism. However, the infection was persistently productive for up to 5 months. The down-regulation of surface CD4 molecules was delayed and virus yields significantly exceeded those obtained in T-cell lines.
Collapse
|