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Venter JC, Adams MD, Myers EW, Li PW, Mural RJ, Sutton GG, Smith HO, Yandell M, Evans CA, Holt RA, Gocayne JD, Amanatides P, Ballew RM, Huson DH, Wortman JR, Zhang Q, Kodira CD, Zheng XH, Chen L, Skupski M, Subramanian G, Thomas PD, Zhang J, Gabor Miklos GL, Nelson C, Broder S, Clark AG, Nadeau J, McKusick VA, Zinder N, Levine AJ, Roberts RJ, Simon M, Slayman C, Hunkapiller M, Bolanos R, Delcher A, Dew I, Fasulo D, Flanigan M, Florea L, Halpern A, Hannenhalli S, Kravitz S, Levy S, Mobarry C, Reinert K, Remington K, Abu-Threideh J, Beasley E, Biddick K, Bonazzi V, Brandon R, Cargill M, Chandramouliswaran I, Charlab R, Chaturvedi K, Deng Z, Di Francesco V, Dunn P, Eilbeck K, Evangelista C, Gabrielian AE, Gan W, Ge W, Gong F, Gu Z, Guan P, Heiman TJ, Higgins ME, Ji RR, Ke Z, Ketchum KA, Lai Z, Lei Y, Li Z, Li J, Liang Y, Lin X, Lu F, Merkulov GV, Milshina N, Moore HM, Naik AK, Narayan VA, Neelam B, Nusskern D, Rusch DB, Salzberg S, Shao W, Shue B, Sun J, Wang Z, Wang A, Wang X, Wang J, Wei M, Wides R, Xiao C, Yan C, Yao A, Ye J, Zhan M, Zhang W, Zhang H, Zhao Q, Zheng L, Zhong F, Zhong W, Zhu S, Zhao S, Gilbert D, Baumhueter S, Spier G, Carter C, Cravchik A, Woodage T, Ali F, An H, Awe A, Baldwin D, Baden H, Barnstead M, Barrow I, Beeson K, Busam D, Carver A, Center A, Cheng ML, Curry L, Danaher S, Davenport L, Desilets R, Dietz S, Dodson K, Doup L, Ferriera S, Garg N, Gluecksmann A, Hart B, Haynes J, Haynes C, Heiner C, Hladun S, Hostin D, Houck J, Howland T, Ibegwam C, Johnson J, Kalush F, Kline L, Koduru S, Love A, Mann F, May D, McCawley S, McIntosh T, McMullen I, Moy M, Moy L, Murphy B, Nelson K, Pfannkoch C, Pratts E, Puri V, Qureshi H, Reardon M, Rodriguez R, Rogers YH, Romblad D, Ruhfel B, Scott R, Sitter C, Smallwood M, Stewart E, Strong R, Suh E, Thomas R, Tint NN, Tse S, Vech C, Wang G, Wetter J, Williams S, Williams M, Windsor S, Winn-Deen E, Wolfe K, Zaveri J, Zaveri K, Abril JF, Guigó R, Campbell MJ, Sjolander KV, Karlak B, Kejariwal A, Mi H, Lazareva B, Hatton T, Narechania A, Diemer K, Muruganujan A, Guo N, Sato S, Bafna V, Istrail S, Lippert R, Schwartz R, Walenz B, Yooseph S, Allen D, Basu A, Baxendale J, Blick L, Caminha M, Carnes-Stine J, Caulk P, Chiang YH, Coyne M, Dahlke C, Deslattes Mays A, Dombroski M, Donnelly M, Ely D, Esparham S, Fosler C, Gire H, Glanowski S, Glasser K, Glodek A, Gorokhov M, Graham K, Gropman B, Harris M, Heil J, Henderson S, Hoover J, Jennings D, Jordan C, Jordan J, Kasha J, Kagan L, Kraft C, Levitsky A, Lewis M, Liu X, Lopez J, Ma D, Majoros W, McDaniel J, Murphy S, Newman M, Nguyen T, Nguyen N, Nodell M, Pan S, Peck J, Peterson M, Rowe W, Sanders R, Scott J, Simpson M, Smith T, Sprague A, Stockwell T, Turner R, Venter E, Wang M, Wen M, Wu D, Wu M, Xia A, Zandieh A, Zhu X. The sequence of the human genome. Science 2001; 291:1304-51. [PMID: 11181995 DOI: 10.1126/science.1058040] [Citation(s) in RCA: 7819] [Impact Index Per Article: 325.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
A 2.91-billion base pair (bp) consensus sequence of the euchromatic portion of the human genome was generated by the whole-genome shotgun sequencing method. The 14.8-billion bp DNA sequence was generated over 9 months from 27,271,853 high-quality sequence reads (5.11-fold coverage of the genome) from both ends of plasmid clones made from the DNA of five individuals. Two assembly strategies-a whole-genome assembly and a regional chromosome assembly-were used, each combining sequence data from Celera and the publicly funded genome effort. The public data were shredded into 550-bp segments to create a 2.9-fold coverage of those genome regions that had been sequenced, without including biases inherent in the cloning and assembly procedure used by the publicly funded group. This brought the effective coverage in the assemblies to eightfold, reducing the number and size of gaps in the final assembly over what would be obtained with 5.11-fold coverage. The two assembly strategies yielded very similar results that largely agree with independent mapping data. The assemblies effectively cover the euchromatic regions of the human chromosomes. More than 90% of the genome is in scaffold assemblies of 100,000 bp or more, and 25% of the genome is in scaffolds of 10 million bp or larger. Analysis of the genome sequence revealed 26,588 protein-encoding transcripts for which there was strong corroborating evidence and an additional approximately 12,000 computationally derived genes with mouse matches or other weak supporting evidence. Although gene-dense clusters are obvious, almost half the genes are dispersed in low G+C sequence separated by large tracts of apparently noncoding sequence. Only 1.1% of the genome is spanned by exons, whereas 24% is in introns, with 75% of the genome being intergenic DNA. Duplications of segmental blocks, ranging in size up to chromosomal lengths, are abundant throughout the genome and reveal a complex evolutionary history. Comparative genomic analysis indicates vertebrate expansions of genes associated with neuronal function, with tissue-specific developmental regulation, and with the hemostasis and immune systems. DNA sequence comparisons between the consensus sequence and publicly funded genome data provided locations of 2.1 million single-nucleotide polymorphisms (SNPs). A random pair of human haploid genomes differed at a rate of 1 bp per 1250 on average, but there was marked heterogeneity in the level of polymorphism across the genome. Less than 1% of all SNPs resulted in variation in proteins, but the task of determining which SNPs have functional consequences remains an open challenge.
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7819 |
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Keech A, Simes RJ, Barter P, Best J, Scott R, Taskinen MR, Forder P, Pillai A, Davis T, Glasziou P, Drury P, Kesäniemi YA, Sullivan D, Hunt D, Colman P, d'Emden M, Whiting M, Ehnholm C, Laakso M. Effects of long-term fenofibrate therapy on cardiovascular events in 9795 people with type 2 diabetes mellitus (the FIELD study): randomised controlled trial. Lancet 2005; 366:1849-61. [PMID: 16310551 DOI: 10.1016/s0140-6736(05)67667-2] [Citation(s) in RCA: 2203] [Impact Index Per Article: 110.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
BACKGROUND Patients with type 2 diabetes mellitus are at increased risk of cardiovascular disease, partly owing to dyslipidaemia, which can be amenable to fibrate therapy. We designed the Fenofibrate Intervention and Event Lowering in Diabetes (FIELD) study to assess the effect of fenofibrate on cardiovascular disease events in these patients. METHODS We did a multinational, randomised controlled trial with 9795 participants aged 50-75 years, with type 2 diabetes mellitus, and not taking statin therapy at study entry. After a placebo and a fenofibrate run-in phase, we randomly assigned patients (2131 with previous cardiovascular disease and 7664 without) with a total-cholesterol concentration of 3.0-6.5 mmol/L and a total-cholesterol/HDL-cholesterol ratio of 4.0 or more or plasma triglyceride of 1.0-5.0 mmol/L to micronised fenofibrate 200 mg daily (n=4895) or matching placebo (n=4900). Our primary outcome was coronary events (coronary heart disease death or non-fatal myocardial infarction); the outcome for prespecified subgroup analyses was total cardiovascular events (the composite of cardiovascular death, myocardial infarction, stroke, and coronary and carotid revascularisation). Analysis was by intention to treat. The study was prospectively registered (number ISRCTN 64783481). FINDINGS Vital status was confirmed on all but 22 patients. Averaged over the 5 years' study duration, similar proportions in each group discontinued study medication (10% placebo vs 11% fenofibrate) and more patients allocated placebo (17%) than fenofibrate (8%; p<0.0001) commenced other lipid treatments, predominantly statins. 5.9% (n=288) of patients on placebo and 5.2% (n=256) of those on fenofibrate had a coronary event (relative reduction of 11%; hazard ratio [HR] 0.89, 95% CI 0.75-1.05; p=0.16). This finding corresponds to a significant 24% reduction in non-fatal myocardial infarction (0.76, 0.62-0.94; p=0.010) and a non-significant increase in coronary heart disease mortality (1.19, 0.90-1.57; p=0.22). Total cardiovascular disease events were significantly reduced from 13.9% to 12.5% (0.89, 0.80-0.99; p=0.035). This finding included a 21% reduction in coronary revascularisation (0.79, 0.68-0.93; p=0.003). Total mortality was 6.6% in the placebo group and 7.3% in the fenofibrate group (p=0.18). Fenofibrate was associated with less albuminuria progression (p=0.002), and less retinopathy needing laser treatment (5.2%vs 3.6%, p=0.0003). There was a slight increase in pancreatitis (0.5%vs 0.8%, p=0.031) and pulmonary embolism (0.7%vs 1.1%, p=0.022), but no other significant adverse effects. INTERPRETATION Fenofibrate did not significantly reduce the risk of the primary outcome of coronary events. It did reduce total cardiovascular events, mainly due to fewer non-fatal myocardial infarctions and revascularisations. The higher rate of starting statin therapy in patients allocated placebo might have masked a moderately larger treatment benefit.
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2203 |
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Fitzgerald TW, Gerety SS, Jones WD, van Kogelenberg M, King DA, McRae J, Morley KI, Parthiban V, Al-Turki S, Ambridge K, Barrett DM, Bayzetinova T, Clayton S, Coomber EL, Gribble S, Jones P, Krishnappa N, Mason LE, Middleton A, Miller R, Prigmore E, Rajan D, Sifrim A, Tivey AR, Ahmed M, Akawi N, Andrews R, Anjum U, Archer H, Armstrong R, Balasubramanian M, Banerjee R, Baralle D, Batstone P, Baty D, Bennett C, Berg J, Bernhard B, Bevan AP, Blair E, Blyth M, Bohanna D, Bourdon L, Bourn D, Brady A, Bragin E, Brewer C, Brueton L, Brunstrom K, Bumpstead SJ, Bunyan DJ, Burn J, Burton J, Canham N, Castle B, Chandler K, Clasper S, Clayton-Smith J, Cole T, Collins A, Collinson MN, Connell F, Cooper N, Cox H, Cresswell L, Cross G, Crow Y, D’Alessandro M, Dabir T, Davidson R, Davies S, Dean J, Deshpande C, Devlin G, Dixit A, Dominiczak A, Donnelly C, Donnelly D, Douglas A, Duncan A, Eason J, Edkins S, Ellard S, Ellis P, Elmslie F, Evans K, Everest S, Fendick T, Fisher R, Flinter F, Foulds N, Fryer A, Fu B, Gardiner C, Gaunt L, Ghali N, Gibbons R, Gomes Pereira SL, Goodship J, Goudie D, Gray E, Greene P, Greenhalgh L, Harrison L, Hawkins R, Hellens S, Henderson A, Hobson E, Holden S, Holder S, Hollingsworth G, Homfray T, Humphreys M, Hurst J, Ingram S, Irving M, Jarvis J, Jenkins L, Johnson D, Jones D, Jones E, Josifova D, Joss S, Kaemba B, Kazembe S, Kerr B, Kini U, Kinning E, Kirby G, Kirk C, Kivuva E, Kraus A, Kumar D, Lachlan K, Lam W, Lampe A, Langman C, Lees M, Lim D, Lowther G, Lynch SA, Magee A, Maher E, Mansour S, Marks K, Martin K, Maye U, McCann E, McConnell V, McEntagart M, McGowan R, McKay K, McKee S, McMullan DJ, McNerlan S, Mehta S, Metcalfe K, Miles E, Mohammed S, Montgomery T, Moore D, Morgan S, Morris A, Morton J, Mugalaasi H, Murday V, Nevitt L, Newbury-Ecob R, Norman A, O'Shea R, Ogilvie C, Park S, Parker MJ, Patel C, Paterson J, Payne S, Phipps J, Pilz DT, Porteous D, Pratt N, Prescott K, Price S, Pridham A, Procter A, Purnell H, Ragge N, Rankin J, Raymond L, Rice D, Robert L, Roberts E, Roberts G, Roberts J, Roberts P, Ross A, Rosser E, Saggar A, Samant S, Sandford R, Sarkar A, Schweiger S, Scott C, Scott R, Selby A, Seller A, Sequeira C, Shannon N, Sharif S, Shaw-Smith C, Shearing E, Shears D, Simonic I, Simpkin D, Singzon R, Skitt Z, Smith A, Smith B, Smith K, Smithson S, Sneddon L, Splitt M, Squires M, Stewart F, Stewart H, Suri M, Sutton V, Swaminathan GJ, Sweeney E, Tatton-Brown K, Taylor C, Taylor R, Tein M, Temple IK, Thomson J, Tolmie J, Torokwa A, Treacy B, Turner C, Turnpenny P, Tysoe C, Vandersteen A, Vasudevan P, Vogt J, Wakeling E, Walker D, Waters J, Weber A, Wellesley D, Whiteford M, Widaa S, Wilcox S, Williams D, Williams N, Woods G, Wragg C, Wright M, Yang F, Yau M, Carter NP, Parker M, Firth HV, FitzPatrick DR, Wright CF, Barrett JC, Hurles ME. Large-scale discovery of novel genetic causes of developmental disorders. Nature 2015; 519:223-8. [PMID: 25533962 PMCID: PMC5955210 DOI: 10.1038/nature14135] [Citation(s) in RCA: 826] [Impact Index Per Article: 82.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2014] [Accepted: 12/04/2014] [Indexed: 12/23/2022]
Abstract
Despite three decades of successful, predominantly phenotype-driven discovery of the genetic causes of monogenic disorders, up to half of children with severe developmental disorders of probable genetic origin remain without a genetic diagnosis. Particularly challenging are those disorders rare enough to have eluded recognition as a discrete clinical entity, those with highly variable clinical manifestations, and those that are difficult to distinguish from other, very similar, disorders. Here we demonstrate the power of using an unbiased genotype-driven approach to identify subsets of patients with similar disorders. By studying 1,133 children with severe, undiagnosed developmental disorders, and their parents, using a combination of exome sequencing and array-based detection of chromosomal rearrangements, we discovered 12 novel genes associated with developmental disorders. These newly implicated genes increase by 10% (from 28% to 31%) the proportion of children that could be diagnosed. Clustering of missense mutations in six of these newly implicated genes suggests that normal development is being perturbed by an activating or dominant-negative mechanism. Our findings demonstrate the value of adopting a comprehensive strategy, both genome-wide and nationwide, to elucidate the underlying causes of rare genetic disorders.
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research-article |
10 |
826 |
4
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36 |
557 |
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Prince DS, Peterson DD, Steiner RM, Gottlieb JE, Scott R, Israel HL, Figueroa WG, Fish JE. Infection with Mycobacterium avium complex in patients without predisposing conditions. N Engl J Med 1989; 321:863-8. [PMID: 2770822 DOI: 10.1056/nejm198909283211304] [Citation(s) in RCA: 474] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Pulmonary disease caused by Mycobacterium avium complex usually occurs in patients with chronic lung disease or deficient cellular immunity, and its prevalence is increasing. We describe 21 patients (mean age, 66 years) with such infection without the usual predisposing factors, representing 18 percent of the 119 patients surveyed. Seventeen women and 4 men were given a diagnosis of M. avium complex from 1978 to 1987, with a stable incidence over the decade, on the basis of pulmonary symptoms, abnormalities on chest films, positive cultures, and in 14, biopsy evidence of invasive disease. Most of the patients (86 percent) presented with persistent cough and purulent sputum, usually without fever or weight loss. The cough was present for a mean of 25 weeks before the correct diagnosis was made. Radiographic patterns of slowly progressive nodular opacities predominated (71 percent); only five patients had cavitary disease at presentation. All patients responded initially to antimycobacterial therapy, but eight eventually relapsed when it was stopped. Four patients died of progressive pulmonary infection caused by M. avium complex. The extent of the initial pulmonary involvement was greater in patients with progressive disease than in those whose condition improved. We conclude that pulmonary disease caused by the M. avium complex can affect persons without predisposing conditions, particularly elderly women, and that recognition of this disease is often delayed because of its indolent nature.
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474 |
6
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Crystal H, Dickson D, Fuld P, Masur D, Scott R, Mehler M, Masdeu J, Kawas C, Aronson M, Wolfson L. Clinico-pathologic studies in dementia: nondemented subjects with pathologically confirmed Alzheimer's disease. Neurology 1988; 38:1682-7. [PMID: 3185902 DOI: 10.1212/wnl.38.11.1682] [Citation(s) in RCA: 389] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
We compared neuropsychological findings in 28 longitudinally evaluated elderly subjects with their postmortem neuropathology, including senile plaque and neurofibrillary tangle counts from standardized sections. Nine of the subjects were not demented when evaluated just prior to their death. Numerous cortical senile plaques and other changes of Alzheimer's disease (AD) occurred in six of nine nondemented old-old subjects. Five of these six subjects had shown decline on yearly neuropsychological tests but their cognitive impairment was too mild to meet clinical criteria for dementia. Whereas cortical senile plaque count did not distinguish well between demented and nondemented subjects, every subject with numerous cortical neurofibrillary tangles was demented. The nondemented subjects with Alzheimer pathology may have had "preclinical" AD, or numerous cortical plaques may occur in some elderly subjects who would never develop clinical dementia.
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389 |
7
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Henderson S, Duncan-Jones P, Byrne DG, Scott R. Measuring social relationships. The Interview Schedule for Social Interaction. Psychol Med 1980; 10:723-734. [PMID: 7208730 DOI: 10.1017/s003329170005501x] [Citation(s) in RCA: 384] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
It is generally recognized that social relationships occupy a central position in psychiatry. To examine the role of social relationships in the onset of minor psychiatric morbidity it is necessary to construct an instrument which will meet the need for a valid, reliable and comprehensive index of social relationships. Such an instrument has now been developed and used in a sample of the general population. The Interview Schedule for Social Interaction arose from a research need, and was constructed to assess the availability and perceived adequacy for any individual of a number of facets of social relationships. These consist both of persons and of the provisions obtained through them. Data from a general population sample suggest this instrument to be sufficiently valid and reliable, and also sensitive to predictable variations between sociodemographic groups, to justify its use in clinical and epidemiological studies, both in psychiatry and general medicine.
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384 |
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Harris WH, Schiller AL, Scholler JM, Freiberg RA, Scott R. Extensive localized bone resorption in the femur following total hip replacement. J Bone Joint Surg Am 1976. [DOI: 10.2106/00004623-197658050-00005] [Citation(s) in RCA: 315] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
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49 |
315 |
9
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Munné S, Magli C, Cohen J, Morton P, Sadowy S, Gianaroli L, Tucker M, Márquez C, Sable D, Ferraretti AP, Massey JB, Scott R. Positive outcome after preimplantation diagnosis of aneuploidy in human embryos. Hum Reprod 1999; 14:2191-9. [PMID: 10469680 DOI: 10.1093/humrep/14.9.2191] [Citation(s) in RCA: 303] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
usromosomal abnormalities are responsible for a great deal of embryo wastage, which is reflected, at least partially, in decreased implantation and increased miscarriage in older women. To address this problem the transfer of only chromosomally normal embryos previously selected by preimplantation genetic diagnosis (PGD) has been proposed. We designed a multi-centre in-vitro fertilization (IVF) study to compare controls and a test group that underwent embryo biopsy and PGD for aneuploidy. Patients were matched retrospectively, but blindly, for average maternal age, number of previous IVF cycles, duration of stimulation, oestradiol concentrations on day +1, and average mature follicles. All these parameters were similar in test and control groups. Only embryos classified as normal for those chromosomes were transferred after PGD. The results showed that the rates of fetal heart beat (FHB)/embryo transferred between the control and test groups were similar. However, spontaneous abortions, measured as FHB aborted/FHB detected, decreased after PGD (P < 0.05), and ongoing pregnancies and delivered babies increased (P < 0.05) in the PGD group of patients. Two conclusions were obtained: (i) PGD of aneuploidy reduced embryo loss after implantation; (ii) implantation rates were not significantly improved, but the proportion of ongoing and delivered babies was increased.
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Clinical Trial |
26 |
303 |
10
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Parikh VS, Morgan MM, Scott R, Clements LS, Butow RA. The mitochondrial genotype can influence nuclear gene expression in yeast. Science 1987; 235:576-80. [PMID: 3027892 DOI: 10.1126/science.3027892] [Citation(s) in RCA: 257] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Isochromosomal, respiratory-deficient yeast strains, such as a mit-, a hypersuppressive petite, and a petite lacking mitochondrial DNA, are phenotypically identical in spite of differences in their mitochondrial genomes. Subtractive hybridizations of complementary DNA's to polyadenylated RNA isolated from derepressed cultures of these strains reveal the presence of nuclear-encoded transcripts whose abundance varies not only between them and their respiratory-competent parent, but among the respiratory-deficient strains themselves. Transcripts of some nuclear-encoded mitochondrial proteins, like cytochrome c and the alpha and beta subunits of the mitochondrial adenosine triphosphatase, whose abundance is affected by glucose or heme, do not vary. In the absence of major metabolic variables, yeast cells seem to respond to the quality and quantity of mitochondrial DNA and modulate the levels of nuclear-encoded RNA's, perhaps as a means of intergenomic regulation.
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38 |
257 |
11
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Trupp M, Scott R, Whittemore SR, Ibáñez CF. Ret-dependent and -independent mechanisms of glial cell line-derived neurotrophic factor signaling in neuronal cells. J Biol Chem 1999; 274:20885-94. [PMID: 10409632 DOI: 10.1074/jbc.274.30.20885] [Citation(s) in RCA: 235] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Glial cell line-derived neurotrophic factor (GDNF) has been shown to signal through a multicomponent receptor complex consisting of the Ret receptor tyrosine kinase and a member of the GFRalpha family of glycosylphosphatidylinositol-anchored receptors. In the current model of GDNF signaling, Ret delivers the intracellular signal but cannot bind ligand on its own, while GFRalphas bind ligand but are thought not to signal in the absence of Ret. We have compared signaling pathways activated by GDNF in two neuronal cell lines expressing different complements of GDNF receptors. In a motorneuron-derived cell line expressing Ret and GFRalphas, GDNF stimulated sustained activation of the Ras/ERK and phosphatidylinositol 3-kinase/Akt pathways, cAMP response element-binding protein phosphorylation, and increased c-fos expression. Unexpectedly, GDNF also promoted biochemical and biological responses in a line of conditionally immortalized neuronal precursors that express high levels of GFRalphas but not Ret. GDNF treatment did not activate the Ras/ERK pathway in these cells, but stimulated a GFRalpha1-associated Src-like kinase activity in detergent-insoluble membrane compartments, rapid phosphorylation of cAMP response element-binding protein, up-regulation of c-fos mRNA, and cell survival. Together, these results offer new insights into the dynamics of GDNF signaling in neuronal cells, and indicate the existence of novel signaling mechanisms directly or indirectly mediated by GFRalpha receptors acting in a cell-autonomous manner independently of Ret.
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26 |
235 |
12
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Cohen J, Scott R, Schimmel T, Levron J, Willadsen S. Birth of infant after transfer of anucleate donor oocyte cytoplasm into recipient eggs. Lancet 1997; 350:186-7. [PMID: 9250192 DOI: 10.1016/s0140-6736(05)62353-7] [Citation(s) in RCA: 227] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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Case Reports |
28 |
227 |
13
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Cohen J, Scott R, Alikani M, Schimmel T, Munné S, Levron J, Wu L, Brenner C, Warner C, Willadsen S. Ooplasmic transfer in mature human oocytes. Mol Hum Reprod 1998; 4:269-80. [PMID: 9570273 DOI: 10.1093/molehr/4.3.269] [Citation(s) in RCA: 219] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Ooplasmic transplantation aimed at restoring normal growth in developmentally compromised oocytes and embryos was evaluated in seven couples (eight cycles) with multiple implantation failures. Two approaches were investigated to transfer ooplasm from donor eggs at metaphase II (MII) stage into patient MII eggs: (i) electrofusion of a ooplasmic donor fragment into each patient egg (three cycles), and (ii) direct injection of a small amount of ooplasm from a donor egg into each patient egg (five cycles). Some donor eggs were used multiple times. Donor eggs were divided into two groups, one being used for ooplasmic extraction and the other one for egg donation. Cleaved embryos resulting from the latter were cryopreserved, where numbers and satisfactory development permitted. A second control group consisted of embryos derived from patient eggs after intracytoplasmic sperm injection without ooplasmic transfer. This was performed when sufficient number of eggs were available (n = 5). Donor eggs (n = 40) were evaluated cytogenetically after micromanipulation in order to confirm the presence of chromosomes. One egg was anuclear and the recipient embryos were not transferred. Normal fertilization was significantly higher after injection of ooplasm (63%) in comparison with fusion (23%). Pronuclear anomalies appeared enhanced after fusion with ooplasts. Embryo morphology was not improved in the three cycles with electrofusion and patients did not become pregnant. An improvement in embryo morphology was noted in two patients after injection of ooplasm and both became pregnant, but one miscarried. A third pregnancy was established in the repeat patient, without obvious embryo improvement. One baby was born and the third pregnancy is ongoing with a normal karyotype. Two other patients with male factor infertility had poor embryos after ooplasmic injection, but the donor embryo controls were also poor. The patients did not become pregnant and had no donor embryos frozen. Ooplasmic transfer at the MII stage may be promising in patients with compromised embryos; however, evaluation of ooplasmic anomalies and optimization of techniques will require further investigation prior to widescale application.
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219 |
14
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Paratcha G, Ledda F, Baars L, Coulpier M, Besset V, Anders J, Scott R, Ibáñez CF. Released GFRalpha1 potentiates downstream signaling, neuronal survival, and differentiation via a novel mechanism of recruitment of c-Ret to lipid rafts. Neuron 2001; 29:171-84. [PMID: 11182089 DOI: 10.1016/s0896-6273(01)00188-x] [Citation(s) in RCA: 217] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Although both c-Ret and GFRalpha1 are required for responsiveness to GDNF, GFRalpha1 is widely expressed in the absence of c-Ret, suggesting alternative roles for "ectopic" sites of GFRalpha1 expression. We show that GFRalpha1 is released by neuronal cells, Schwann cells, and injured sciatic nerve. c-Ret stimulation in trans by soluble or immobilized GFRalpha1 potentiates downstream signaling, neurite outgrowth, and neuronal survival, and elicits dramatic localized expansions of axons and growth cones. Soluble GFRalpha1 mediates robust recruitment of c-Ret to lipid rafts via a novel mechanism requiring the c-Ret tyrosine kinase. Activated c-Ret associates with different adaptor proteins inside and outside lipid rafts. These results provide an explanation for the tissue distribution of GFRalpha1, supporting the physiological importance of c-Ret activation in trans as a novel mechanism to potentiate and diversify the biological responses to GDNF.
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Jorm AF, Scott R, Cullen JS, MacKinnon AJ. Performance of the Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE) as a screening test for dementia. Psychol Med 1991; 21:785-790. [PMID: 1946866 DOI: 10.1017/s0033291700022418] [Citation(s) in RCA: 206] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
A 26-item informant questionnaire (IQCODE) and the Mini-Mental State Examination (MMSE) were compared as screening tests for dementia in a sample of 69 patients. Dementia diagnoses were made by both a clinician and a research interview using a computer algorithm to meet DSM-III-R and ICD-10 (Draft) criteria. The IQCODE was found to perform at least as well as the MMSE against all diagnoses and significantly better when judged against the algorithmic ICD-10 diagnoses. Also, the IQCODE was found to be uncontaminated by pre-morbid ability as estimated from the National Adult Reading Test and to have very high test-retest reliability after a delay of a day or more.
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Comparative Study |
34 |
206 |
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Quigley HA, Enger C, Katz J, Sommer A, Scott R, Gilbert D. Risk factors for the development of glaucomatous visual field loss in ocular hypertension. ARCHIVES OF OPHTHALMOLOGY (CHICAGO, ILL. : 1960) 1994; 112:644-9. [PMID: 8185522 DOI: 10.1001/archopht.1994.01090170088028] [Citation(s) in RCA: 195] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
OBJECTIVE To detect characteristics of persons with ocular hypertension that are associated with a higher risk of future glaucomatous field loss. METHODS Annual examinations of the optic disc, nerve fiber layer, and visual field in 647 persons with bilateral intraocular pressure higher than 21 mmHg and initially normal visual field test results with the Goldmann perimeter. RESULTS Sixty-eight persons developed a field defect on two consecutive Goldmann visual field tests in at least one eye, while 579 others retained normal fields. Moderate or severe nerve fiber layer atrophy at baseline was associated with a seven to eight times greater risk of development of visual field loss. Attributes that were significantly associated with the incidence of field loss included older age, larger cup-disc ratio, smaller rim-disc area ratio, larger cup asymmetry, presence of disc crescent, and higher intraocular pressure. Characteristics found not to be associated with incidence were gender, race, hypertension, diabetes, refractive error, family history of glaucoma, smoking or alcohol drinking history, and disc area. CONCLUSIONS Increasing nerve fiber layer atrophy judged by a semiquantitative grading system was associated with increasing risk of development of visual field loss among persons with ocular hypertension. The relationship of the development of field loss to race, myopia, family history of glaucoma, and medical history are more complex than has been presumed.
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31 |
195 |
17
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Chan JCN, Scott R, Arjona Ferreira JC, Sheng D, Gonzalez E, Davies MJ, Stein PP, Kaufman KD, Amatruda JM, Williams-Herman D. Safety and efficacy of sitagliptin in patients with type 2 diabetes and chronic renal insufficiency. Diabetes Obes Metab 2008; 10:545-55. [PMID: 18518892 DOI: 10.1111/j.1463-1326.2008.00914.x] [Citation(s) in RCA: 193] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
OBJECTIVE To assess the safety of sitagliptin in patients with type 2 diabetes and moderate [creatinine clearance (CrCl) > or =30 to <50 ml/min] or severe renal insufficiency [CrCl <30 ml/min including patients with end-stage renal disease (ESRD) on dialysis]. The efficacy of sitagliptin in this patient population was also assessed. METHODS In a 54-week, randomized, double-blind, parallel-group study, patients with baseline glycosylated haemoglobin A(1c) (HbA(1c)) values of 6.5-10% were allocated (2:1) to sitagliptin (for 54 weeks) or the sequence of placebo (for 12 weeks) followed by active treatment with glipizide (for 42 weeks). To achieve plasma concentrations similar to those observed in patients with normal renal function treated with 100 mg sitagliptin once daily, patients with moderate renal insufficiency were allocated to receive sitagliptin 50 mg once daily and patients with severe renal insufficiency to receive 25 mg once daily. Glipizide treatment was initiated at 2.5 or 5 mg/day and uptitrated to a maximum of 20 mg/day. RESULTS Patients (N = 91) with a mean baseline HbA(1c) value of 7.7% (range: 6.2-10.3%) were randomized to sitagliptin (n = 65) or placebo (n = 26). After 12 weeks, the mean change [95% confidence interval (CI)] from baseline in HbA(1c) was -0.6% (-0.8, -0.4) in the sitagliptin group compared with -0.2% (-0.4, 0.1) in the placebo group [between-group difference (95% CI) = -0.4% (-0.7, -0.1)]. At 54 weeks, patients continuously treated with sitagliptin had a mean change (95% CI) from baseline in HbA(1c) of -0.7% (-0.9, -0.4). The overall incidence of adverse experiences was generally similar between groups. Between-group differences in incidences of specific clinical adverse experiences were generally small; however, the proportion of patients for whom hypoglycaemia was reported was lower in the sitagliptin group (4.6%) compared with the placebo/glipizide group (23.1%). Consistent with the high mortality risk in this patient population, there were six deaths during this 54-week study [5 of 65 patients (7.7%) in the sitagliptin group and 1 of 26 patients (3.8%) in the placebo/glipizide group]; no death was considered by the investigator to be drug related. The overall incidences of drug-related and serious adverse experiences and discontinuations because of adverse experiences were generally similar between groups. CONCLUSIONS In this study, sitagliptin was generally well tolerated and provided effective glycaemic control in patients with type 2 diabetes and moderate to severe renal insufficiency, including patients with ESRD on dialysis.
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Multicenter Study |
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193 |
18
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Kay DW, Henderson AS, Scott R, Wilson J, Rickwood D, Grayson DA. Dementia and depression among the elderly living in the Hobart community: the effect of the diagnostic criteria on the prevalence rates. Psychol Med 1985; 15:771-788. [PMID: 4080881 DOI: 10.1017/s0033291700005006] [Citation(s) in RCA: 190] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
A survey was made of 274 non-institutionalized persons aged 70 and over living in Hobart. The prevalence of dementia and of depression was measured by interviewing subjects using a modified version of the Geriatric Mental State Schedule (GMS) (Copeland et al. 1976) and the Mini Mental State Examination (MMSE) (Folstein et al. 1975). Rates of morbidity were derived from different diagnostic procedures. These were: diagnoses made by a psychiatrist (A.S.H.) directly from the interview schedules and audiotapes, and rated as mild, moderate or severe; the criteria laid down in DSM-III, converted into algorithms describing 3 degrees of severity; and the algorithms for pervasive dementia and depression proposed by Gurland et al. (1983), and from these authors' rational scales. In addition, the relation between scales for dementia and for depression and the diagnosed categories was examined. Some problems in applying these methods to aged persons in the community are discussed. It is concluded that more detailed specification of criteria is desirable if the comparative epidemiology of dementia and depression in old age is to advance.
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Comparative Study |
40 |
190 |
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Scott R, Loeys T, Davies MJ, Engel SS. Efficacy and safety of sitagliptin when added to ongoing metformin therapy in patients with type 2 diabetes. Diabetes Obes Metab 2008; 10:959-69. [PMID: 18201203 DOI: 10.1111/j.1463-1326.2007.00839.x] [Citation(s) in RCA: 184] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
AIM To assess the addition of sitagliptin to ongoing metformin therapy in patients with type 2 diabetes who were inadequately controlled [haemoglobin A(1c) (HbA(1c)) 7-11%] on metformin monotherapy. METHODS Patients (n = 273) on metformin (>/=1500 mg/day) were randomized to receive the addition of once-daily placebo, sitagliptin 100 mg or rosiglitazone 8 mg in a 1 : 1 : 1 ratio for 18 weeks. The efficacy analysis was based on the all-patients-treated population using an analysis of co-variance with change in HbA(1c) from baseline as the primary endpoint. RESULTS The mean baseline HbA(1c) was 7.7% for the entire cohort. After 18 weeks, both active add-on therapies led to greater improvements in HbA(1c) from baseline: -0.73% for sitagliptin (p < 0.001 vs. placebo) and -0.79% for rosiglitazone compared with -0.22% for placebo. No difference was observed between the sitagliptin and rosiglitazone treatments (0.06% [95% confidence interval (CI): -0.14 to 0.25]). The proportion of patients achieving an HbA(1c) < 7% was greater with sitagliptin (55%) and rosiglitazone (63%) compared with placebo (38%). Body weight increased from baseline with rosiglitazone (1.5 kg) compared with body weight reduction with sitagliptin (-0.4 kg) and placebo (-0.8 kg). The difference in body weight between the sitagliptin and rosiglitazone groups was 1.9 kg (95% CI: 1.3-2.5). In a prespecified analysis, the proportion of patients experiencing a greater than 3-kg increase in body weight was 21% in the rosiglitazone group compared with 2% in both the sitagliptin and placebo groups. Both active treatments were generally well tolerated, with no increased risk of hypoglycaemia or gastrointestinal adverse events compared with placebo. CONCLUSIONS In this 18-week study, the addition of sitagliptin was effective and well tolerated in patients with type 2 diabetes inadequately controlled with metformin monotherapy. Treatment with sitagliptin produced similar reductions in HbA(1c) compared with the addition of rosiglitazone.
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Comparative Study |
17 |
184 |
20
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Scott R, Wu M, Sanchez M, Stein P. Efficacy and tolerability of the dipeptidyl peptidase-4 inhibitor sitagliptin as monotherapy over 12 weeks in patients with type 2 diabetes. Int J Clin Pract 2007; 61:171-80. [PMID: 17156104 DOI: 10.1111/j.1742-1241.2006.01246.x] [Citation(s) in RCA: 181] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
The aim of this study was to assess the efficacy and tolerability of the dipeptidyl peptidase-4 inhibitor, sitagliptin, in patients with type 2 diabetes who have inadequate glycaemic control on diet and exercise. In a randomised, double-blind, placebo- and active-controlled study, 743 patients with type 2 diabetes and a mean baseline HbA(1c) of 7.9% were randomised to receive one of six treatments for 12 weeks: placebo, sitagliptin 5, 12.5, 25 or 50 mg b.i.d., or glipizide 5 mg/day (electively titrated up to 20 mg/day). At week 12, treatment with sitagliptin at all doses tested led to a significant (p < 0.001) reduction in HbA(1c) relative to placebo, with the largest reductions occurring in the 50-mg b.i.d. group. The placebo-subtracted differences in HbA(1c) for the sitagliptin dose groups ranged from -0.38% to -0.77% in a dose-dependent manner, and -1.00% in the glipizide group. Sitagliptin also produced significant reductions in fasting plasma glucose and mean daily glucose across the dose range studied. Sitagliptin treatment was well tolerated and resulted in no significant weight change relative to placebo. There was a modest weight gain observed with glipizide treatment relative to placebo. Hypoglycaemia adverse experiences were reported with the highest incidence in the glipizide group (17%) compared with the placebo (2%) or sitagliptin groups (0-4%, not dose-dependent). In summary, in this study sitagliptin improved glycaemic control, with 50 mg b.i.d. being the most effective dose, and was generally well-tolerated in patients with type 2 diabetes.
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Randomized Controlled Trial |
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181 |
21
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Downham MA, Scott R, Sims DG, Webb JK, Gardner PS. Breast-feeding protects against respiratory syncytial virus infections. BRITISH MEDICAL JOURNAL 1976; 2:274-6. [PMID: 953560 PMCID: PMC1687881 DOI: 10.1136/bmj.2.6030.274] [Citation(s) in RCA: 173] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Eight out of 115 infants admitted to hospital with respiratory syncytial (RS) virus infection had been breast-fed compared with 46 out of 167 controls; this difference was statistically significant. Twenty-one specimens of human colostrum were examined, and all contained RS virus neutralising activity. Specific IgA and IgG were detected in 18 specimens, whereas IgM was detected in none. The titre of IgA antibody was usually higher and correlated more closely to the titre of neutralising activity than that of IgG. Infants inhale milk feeds and regurgitate them through the nose, and the IgA collecting in the respiratory tract might protect against severe respiratory infection. Alternatively, if severe RS virus illness is a sign of hypersensitivity to the virus breast-feeding might protect the infant from an early sensitising infection.
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research-article |
49 |
173 |
22
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Herz MI, Lamberti JS, Mintz J, Scott R, O'Dell SP, McCartan L, Nix G. A program for relapse prevention in schizophrenia: a controlled study. ARCHIVES OF GENERAL PSYCHIATRY 2000; 57:277-83. [PMID: 10711914 DOI: 10.1001/archpsyc.57.3.277] [Citation(s) in RCA: 168] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
BACKGROUND This study examined whether a program for relapse prevention (PRP) is more effective than treatment as usual (TAU) in reducing relapse and rehospitalization rates among outpatients with schizophrenia. METHODS Eighty-two outpatients with DSM-III-R schizophrenia or schizoaffective disorder were randomly assigned to receive either PRP (experimental group, n = 41) or TAU (control group, n = 41) and were followed up for an 18-month prospective controlled study. Patients in both groups were prescribed standard doses of maintenance antipsychotic medication. Treatment with PRP consisted of a combination of psychoeducation, active monitoring for prodromal symptoms with clinical intervention when such symptoms occurred, weekly group therapy for patients, and multifamily groups. The TAU consisted of biweekly individual supportive therapy and medication management. RESULTS Outcome rates over 18 months were 17% for relapse (7 patients) and 22% for rehospitalization (9 patients) in the PRP group, compared with 34% for relapse (14 patients) and 39% for rehospitalization (16 patients) in the TAU group (P = .01 and P = .03, respectively). Addition of age, sex, baseline Global Assessment Scale score, Positive and Negative Syndrome Scale scores (3 measures), and substance abuse to the proportional hazards regression models all yielded nonsignificant effects. The PRP teams were much more likely than the TAU psychiatrists to identify prodromal episodes before patients met objective relapse criteria or needed hospitalization. CONCLUSIONS The PRP was effective in detecting prodromal symptoms of relapse early in an episode. Crisis intervention including increased antipsychotic medication use during the prodromal phase reduced relapse and rehospitalization rates.
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Clinical Trial |
25 |
168 |
23
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Henderson S, Duncan-Jones P, Byrne DG, Scott R, Adcock S. Psychiatric disorder in Canberra. A standardised study of prevalence. Acta Psychiatr Scand 1979; 60:355-74. [PMID: 316261 DOI: 10.1111/j.1600-0447.1979.tb00285.x] [Citation(s) in RCA: 167] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
A standardised survey of prevalence has been carried out in a general population. The epidemiological method employed is innovative in its use of two established instruments, the GHQ and the PSE, harnessed together in a two-phase design. 756 persons were interviewed, giving a response rate of 85% in phase 1. 157 were then interviewed with the PSE in phase 2 within a few days, giving a response rate of 92% in this weighted subsample. The point prevalence of non-psychotic morbidity, based on the distribution of GHQ scores, is higher than elsewhere in Australia, the excess being in Canberra males. The PSE data weighted back to represent the total population, show a distribution of morbidity in women which is remarkably similar to that in the very different population of Camberwell. The overall point prevalence of threshold and definite cases is 9.0% +/- 3.2. Case rates did not vary significantly with age or sex, but were higher in the separated, the single and the widowed. This study represents an advance in the reliable and economical detection of psychiatric morbidity at specified levels of severity in general populations.
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46 |
167 |
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Henderson S, Byrne DG, Duncan-Jones P, Adcock S, Scott R, Steele GP. Social bonds in the epidemiology of neurosis: a preliminary communication. Br J Psychiatry 1978; 132:463-6. [PMID: 656709 DOI: 10.1192/bjp.132.5.463] [Citation(s) in RCA: 161] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
In a random sample of the general population (N = 142) a strong inverse relationship was found between social bonds and the presence of neurotic symptoms. This association was strongest in the case of close affectional ties. Together, measures of social bonds accounted for 47 per cent of the variance in neurotic symptoms. While there is likely to be contamination between the two sets of variables, and while the data do not indicate the direction of causality, these findings constitute an aetiological lead which should be pursued.
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161 |
25
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Aarts MG, Hodge R, Kalantidis K, Florack D, Wilson ZA, Mulligan BJ, Stiekema WJ, Scott R, Pereira A. The Arabidopsis MALE STERILITY 2 protein shares similarity with reductases in elongation/condensation complexes. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 1997; 12:615-623. [PMID: 9351246 DOI: 10.1046/j.1365-313x.1997.00615.x] [Citation(s) in RCA: 154] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
The Arabidopsis thaliana MALE STERILITY 2 (MS2) gene product is involved in male gametogenesis. The first abnormalities in pollen development of ms2 mutants are seen at the stage in microsporogenesis when microspores are released from tetrads. Expression of the MS2 gene is observed in tapetum of wild-type flowers at, and shortly after, the release of microspores from tetrads. The MS2 promoter controls GUS expression at a comparable stage in the tapetum of transgenic tobacco containing an MS2 promoter-GUS fusion. The occasional pollen grains produced by mutant ms2 plants have very thin pollen walls. They are also sensitive to acetolysis treatment, which is a test for the presence of an exine layer. The MS2 gene product shows sequence similarity to a jojoba protein that converts wax fatty acids to fatty alcohols. A possible function of the MS2 protein as a fatty acyl reductase in the formation of pollen wall substances is discussed.
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28 |
154 |