1
|
Cameron E, Pauling L. Supplemental ascorbate in the supportive treatment of cancer: Prolongation of survival times in terminal human cancer. Proc Natl Acad Sci U S A 1976; 73:3685-9. [PMID: 1068480 PMCID: PMC431183 DOI: 10.1073/pnas.73.10.3685] [Citation(s) in RCA: 393] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Ascorbic acid metabolism is associated with a number of mechanisms known to be involved in host resistance to malignant disease. Cancer patients are significantly depleted of ascorbic acid, and in our opinion this demonstrable biochemical characteristic indicates a substantially increased requirement and utilization of this substance to potentiate these various host resistance factors. The results of a clinical trial are presented in which 100 terminal cancer patients were given supplemental ascorbate as part of their routine management. Their progress is compared to that of 1000 similar patients treated identically, but who received no supplemental ascorbate. The mean survival time is more than 4.2 times as great for the ascorbate subjects (more than 210 days) as for the controls (50 days). Analysis of the survival-time curves indicates that deaths occur for about 90% of the ascorbate-treated patients at one-third the rate for the controls and that the other 10% have a much greater survival time, averaging more than 20 times that for the controls. The results clearly indicate that this simple and safe form of medication is of definite value in the treatment of patients with advanced cancer.
Collapse
|
research-article |
49 |
393 |
2
|
Doty RL, Cameron EL. Sex differences and reproductive hormone influences on human odor perception. Physiol Behav 2009; 97:213-28. [PMID: 19272398 DOI: 10.1016/j.physbeh.2009.02.032] [Citation(s) in RCA: 302] [Impact Index Per Article: 18.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2009] [Revised: 01/29/2009] [Accepted: 02/20/2009] [Indexed: 10/21/2022]
Abstract
The question of whether men and women differ in their ability to smell has been the topic of scientific investigation for over a hundred years. Although conflicting findings abound, most studies suggest that, for at least some odorants, women outperform men on tests of odor detection, identification, discrimination, and memory. Most functional imaging and electrophysiological studies similarly imply that, when sex differences are present, they favor women. In this review we examine what is known about sex-related alterations in human smell function, including influences of the menstrual cycle, pregnancy, gonadectomy, and hormone replacement therapy on a range of olfactory measures. We conclude that the relationship between reproductive hormones and human olfactory function is complex and that simple associations between circulating levels of gonadal hormones and measures of olfactory function are rarely present.
Collapse
|
Review |
16 |
302 |
3
|
Cameron E, Pauling L. Supplemental ascorbate in the supportive treatment of cancer: reevaluation of prolongation of survival times in terminal human cancer. Proc Natl Acad Sci U S A 1978; 75:4538-42. [PMID: 279931 PMCID: PMC336151 DOI: 10.1073/pnas.75.9.4538] [Citation(s) in RCA: 284] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
A study has been made of the survival times of 100 terminal cancer patients who were given supplemental ascorbate, usually 10 g/day, as part of their routine management and 1000 matched controls, similar patients who had received the same treatment except for the ascorbate. The two sets of patients were in part the same as those used in our earlier study [Cameron, E. & Pauling, L. (1976) Proc. Natl. Acad. Sci. USA 73, 3685-3689]. Tests confirm that the ascorbate-treated patients and the matched controls are representative subpopulations of the same population of "untreatable" patients. Survival times were measured not only from the date of "untreatability" but also from the precisely known date of first hospital attendance for the cancer that eventually reached the terminal stage. The ascorbate-treated patients were found to have a mean survival time about 300 days greater than that of the controls. Survival times greater than 1 yr after the date of untreatability were observed for 22% of the ascorbate-treated patients and for 0.4% of the controls. The mean survival time of these 22 ascorbate-treated patients is 2.4 yr after reaching the apparently terminal stage; 8 of the ascorbate-treated patients are still alive, with a mean survival time after untreatability of 3.5 yr.
Collapse
|
research-article |
47 |
284 |
4
|
Cameron E, Campbell A. The orthomolecular treatment of cancer. II. Clinical trial of high-dose ascorbic acid supplements in advanced human cancer. Chem Biol Interact 1974; 9:285-315. [PMID: 4430016 DOI: 10.1016/0009-2797(74)90019-2] [Citation(s) in RCA: 226] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
|
|
51 |
226 |
5
|
Carrasco M, Talgar CP, Cameron EL. Characterizing visual performance fields: effects of transient covert attention, spatial frequency, eccentricity, task and set size. SPATIAL VISION 2001; 15:61-75. [PMID: 11893125 PMCID: PMC4332623 DOI: 10.1163/15685680152692015] [Citation(s) in RCA: 208] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
We investigated whether transient covert attention would differentially affect 'performance fields' (shape depicted by percent correct performance at particular locations in the visual field) for orientation discrimination, detection and localization tasks, while manipulating a number of visual factors. We found that although attention improved overall performance, it did not affect performance fields. Two patterns were observed regardless of the presence of a local post-mask, the stimulus orientation, or the task. A horizontal-vertical anisotropy (HVA) became more pronounced as spatial frequency, eccentricity and set size increased. A vertical meridian asymmetry (VMA) became more pronounced as spatial frequency and eccentricity increased. We conclude that performance fields are determined by visual, rather than by transient attentional, constraints.
Collapse
|
research-article |
24 |
208 |
6
|
Abstract
We examined the effect of transient covert attention on the psychometric function for contrast sensitivity in an orientation discrimination task when the target was presented alone in the absence of distracters and visual masks. Transient covert attention decreased both the threshold (consistent with a contrast gain mechanism) and, less consistently, the slope of the psychometric function. We assessed performance at 8 equidistant locations (4.5 degrees eccentricity) and found that threshold and slope depended on target location-both were higher on the vertical than the horizontal meridian, particularly directly above fixation. All effects were robust across a range of spatial frequencies, and the visual field asymmetries increased with spatial frequency. Notwithstanding the dependence of the psychometric function on target location, attention improved performance to a similar extent across the visual field.Given that, in this study, we excluded all sources of external noise, and that we showed experimentally that spatial uncertainty cannot explain the present results, we conclude that the observed attentional benefit is consistent with signal enhancement.
Collapse
|
|
23 |
199 |
7
|
Stewart M, Terry A, Hu M, O'Hara M, Blyth K, Baxter E, Cameron E, Onions DE, Neil JC. Proviral insertions induce the expression of bone-specific isoforms of PEBP2alphaA (CBFA1): evidence for a new myc collaborating oncogene. Proc Natl Acad Sci U S A 1997; 94:8646-51. [PMID: 9238031 PMCID: PMC23059 DOI: 10.1073/pnas.94.16.8646] [Citation(s) in RCA: 184] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
The til-1 locus was identified as a common retroviral integration site in virus-accelerated lymphomas of CD2-myc transgenic mice. We now show that viral insertions at til-1 lead to transcriptional activation of PEBP2alphaA (CBFA1), a transcription factor related to the Drosophila segmentation gene product, Runt. Insertions are upstream and in the opposite orientation to the gene and appear to activate a variant promoter that is normally silent in T cells. Activity of this promoter was detected in rodent osteogenic sarcoma cells and primary osteoblasts, implicating bone as the normal site of promoter activity. The isoforms encoded by the activated gene all encompass the conserved runt DNA-binding domain and share a novel N terminus different from the previously reported PEBP2alphaA products. Minor products include isoforms with internal deletions due to exon skipping and a novel C-terminal domain unrelated to known runt domain factors. The major isoform expressed from the activated til-1 locus (G1) was found to account for virtually all of the core binding factor activity in nuclear extracts from its corresponding lymphoma cell line. Another member of this gene family, AML1(CBFA2), is well known for its involvement in human hemopoietic tumors. These results provide evidence of a direct oncogenic role for PEBP2alphaA and indicate that the Myc and Runt family genes can cooperate in oncogenesis.
Collapse
|
research-article |
28 |
184 |
8
|
Arnott SJ, Duncan W, Kerr GR, Walbaum PR, Cameron E, Jack WJ, Mackillop WJ. Low dose preoperative radiotherapy for carcinoma of the oesophagus: results of a randomized clinical trial. Radiother Oncol 1992; 24:108-13. [PMID: 1496141 DOI: 10.1016/0167-8140(92)90287-5] [Citation(s) in RCA: 164] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
One-hundred-and-seventy-six patients with potentially operable squamous cell carcinoma or adenocarcinoma of the middle or lower thirds of the oesophagus were randomly assigned to preoperative radiotherapy or surgery alone. Patients assigned to the radiotherapy arm received 20 Gy in 10 treatments over 2 weeks, using parallel opposed 4 MV beams. The preoperative radiotherapy was not associated with any significant acute morbidity or any increase in operative complications. The median survival of the overall group of 176 patients was 8 months, and the 5-year survival was 13%. There was no significant difference in the survival of the 90 patients who received preoperative radiotherapy and the 86 who were managed by surgery alone. Proportional hazards analysis identified lymph node involvement, high tumour grade and male sex as significant adverse prognostic features, but the treatment option assigned had no prognostic significance. It was concluded that low dose preoperative radiotherapy offered no advantage over surgery alone.
Collapse
|
Clinical Trial |
33 |
164 |
9
|
Abstract
Recent work on sexual selection and sexual conflict has explored the influence of indirect effects on the evolution of female mating behaviour. It has been suggested that the importance of these effects has been underestimated and that the influence of indirect effects may actually be of relatively greater significance than direct effects. Additionally, it has also been suggested that all indirect effects, both good genes and sexy son, are qualitatively equivalent. Here a counterpoint to these suggestions is offered. We argue two main points: (1) it is unlikely that indirect effects will commonly outweigh direct effects, and (2) that there are important differences between good genes and sexy son indirect effects that must be recognized. We suggest that acknowledgement of these distinctions will lead to increased understanding of processes operating in both sexual conflict and sexual selection.
Collapse
|
|
22 |
129 |
10
|
Smith MD, Kappell DF, Province MA, Hong BA, Robson AM, Dutton S, Guzman T, Hoff J, Shelton L, Cameron E. Living-related kidney donors: a multicenter study of donor education, socioeconomic adjustment, and rehabilitation. Am J Kidney Dis 1986; 8:223-33. [PMID: 3532770 DOI: 10.1016/s0272-6386(86)80030-0] [Citation(s) in RCA: 86] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
To determine the consequences of living-related kidney donation, a study was conducted of 536 donors whose nephrectomies had been performed at nine geographically dispersed centers during the past 12 years. The data demonstrated that greater than 84.0% of the donors thought they had been adequately informed regarding all aspects of donation, and less than 15.0% reported being pressured in their decision. Only two serious medical complications were directly attributable to the surgery, greater than 92.0% of the donors believed their health had not been adversely affected by donation, and 96.8% reaffirmed their decision regardless of the graft's success or the financial distress they experienced (P greater than .05). However, greater than 14.0% experienced direct pressure, particularly not to donate. Donation also appeared to stress previously troubled marriages, especially among donors without a religious affiliation, who were pressured to donate by their families, or who borrowed from family members (P less than .05). Substantial unreimbursed expenses (greater than or equal to $1,000) were incurred by 43 donors, and 23.2% of all donors reported that donation caused a financial hardship.
Collapse
|
|
39 |
86 |
11
|
Cameron EL, Baker CL, Boulton JC. Spatial frequency selective mechanisms underlying the motion aftereffect. Vision Res 1992; 32:561-8. [PMID: 1604843 DOI: 10.1016/0042-6989(92)90248-h] [Citation(s) in RCA: 85] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The motion aftereffect (MAE) was used to study the spatial frequency selectivity of suprathreshold motion perception. Observers were adapted to drifting sine-wave gratings confined to a retinal eccentricity of approx. 4 deg. The magnitude of the subsequent MAE was measured while viewing a stationary sine-wave grating test surface of one of a number of spatial frequencies. The largest MAE was found when the spatial frequency of the test stimulus was the same as that of the adapting stimulus. This phenomenon held for spatial frequencies between 0.5 and 4 c/deg, and was robust with changes in contrast of either adapting or test gratings. However, at an adapting spatial frequency of 0.25 c/deg, the peak MAE was observed at 0.5 c/deg. Control experiments indicated that this peak shift was not the result of the reduced number of cycles in the stimulus, nor the temporal frequency. There was no measurable MAE at spatial frequencies lower than 0.25 c/deg. These results suggest the existence of a "lowest adaptable channel" for the motion aftereffect.
Collapse
|
|
33 |
85 |
12
|
Cameron E, Johnston G, Crofts S, Morton NS. The minimum effective dose of lignocaine to prevent injection pain due to propofol in children. Anaesthesia 1992; 47:604-6. [PMID: 1626674 DOI: 10.1111/j.1365-2044.1992.tb02335.x] [Citation(s) in RCA: 76] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
In a single-blind study of 100 children aged 1 to 10 years, the minimum effective dose of lignocaine required to prevent injection pain due to propofol was 0.2 mg.kg-1 when veins on the dorsum of the hand were used. This is more than twice the adult value. We concluded that injection pain should not limit the use of propofol in children if an adequate amount of lignocaine is mixed immediately prior to injection.
Collapse
|
Clinical Trial |
33 |
76 |
13
|
Cameron E, Pauling L. The orthomolecular treatment of cancer. I. The role of ascorbic acid in host resistance. Chem Biol Interact 1974; 9:273-83. [PMID: 4609626 DOI: 10.1016/0009-2797(74)90018-0] [Citation(s) in RCA: 72] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
|
Review |
51 |
72 |
14
|
Cameron E, Pauling L. Ascorbic acid and the glycosaminoglycans. An orthomolecular approach to cancer and other diseases. Oncology 1973; 27:181-92. [PMID: 4267127 DOI: 10.1159/000224733] [Citation(s) in RCA: 64] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
|
Review |
52 |
64 |
15
|
Cameron E, Campbell A, Jack T. The orthomolecular treatment of cancer. III. Reticulum cell sarcoma: double complete regression induced by high-dose ascorbic acid therapy. Chem Biol Interact 1975; 11:387-93. [PMID: 1104207 DOI: 10.1016/0009-2797(75)90007-1] [Citation(s) in RCA: 59] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The response of a patient with histologically proven reticulum cell sarcoma to no treatment other than large doses of ascorbic acid is described. At the time of first diagnosis, the disease was widely disseminated, and a very dramatic regression of all parameters of disease activity was induced by the continuous administration of large doses of ascorbic acid. Reduction in dosage some months later coincided with reactivation of the disease process. The reinstitution of regular high-dose ascorbic acid therapy induced a second complete remission. The case report is illustrated by serial radiographs. The significance of the therapeutic response is briefly discussed in relation to general schemes of cancer management.
Collapse
|
Case Reports |
50 |
59 |
16
|
Cameron EL, Tai JC, Eckstein MP, Carrasco M. Signal detection theory applied to three visual search tasks — identification, yes/no detection and localization. ACTA ACUST UNITED AC 2004; 17:295-325. [PMID: 15559107 DOI: 10.1163/1568568041920212] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Adding distracters to a display impairs performance on visual tasks (i.e. the set-size effect). While keeping the display characteristics constant, we investigated this effect in three tasks: 2 target identification, yes-no detection with 2 targets, and 8-alternative localization. A Signal Detection Theory (SDT) model, tailored for each task, accounts for the set-size effects observed in identification and localization tasks, and slightly under-predicts the set-size effect in a detection task. Given that sensitivity varies as a function of spatial frequency (SF), we measured performance in each of these three tasks in neutral and peripheral precue conditions for each of six spatial frequencies (0.5-12 cpd). For all spatial frequencies tested, performance on the three tasks decreased as set size increased in the neutral precue condition, and the peripheral precue reduced the effect. Larger set-size effects were observed at low SFs in the identification and localization tasks. This effect can be described using the SDT model, but was not predicted by it. For each of these tasks we also established the extent to which covert attention modulates performance across a range of set sizes. A peripheral precue substantially diminished the set-size effect and improved performance, even at set size 1. These results provide support for distracter exclusion, and suggest that signal enhancement may also be a mechanism by which covert attention can impose its effect.
Collapse
|
|
21 |
53 |
17
|
Wotton S, Terry A, Kilbey A, Jenkins A, Herzyk P, Cameron E, Neil JC. Gene array analysis reveals a common Runx transcriptional programme controlling cell adhesion and survival. Oncogene 2008; 27:5856-66. [PMID: 18560354 DOI: 10.1038/onc.2008.195] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The Runx genes are important in development and cancer, where they can act either as oncogenes or tumour suppressors. We compared the effects of ectopic Runx expression in established fibroblasts, where all three genes produce an indistinguishable phenotype entailing epithelioid morphology and increased cell survival under stress conditions. Gene array analysis revealed a strongly overlapping transcriptional signature, with no examples of opposing regulation of the same target gene. A common set of 50 highly regulated genes was identified after further filtering on regulation by inducible RUNX1-ER. This set revealed a strong bias toward genes with annotated roles in cancer and development, and a preponderance of targets encoding extracellular or surface proteins, reflecting the marked effects of Runx on cell adhesion. Furthermore, in silico prediction of resistance to glucocorticoid growth inhibition was confirmed in fibroblasts and lymphoid cells expressing ectopic Runx. The effects of fibroblast expression of common RUNX1 fusion oncoproteins (RUNX1-ETO, TEL-RUNX1 and CBFB-MYH11) were also tested. Although two direct Runx activation target genes were repressed (Ncam1 and Rgc32), the fusion proteins appeared to disrupt the regulation of downregulated targets (Cebpd, Id2 and Rgs2) rather than impose constitutive repression. These results elucidate the oncogenic potential of the Runx family and reveal novel targets for therapeutic inhibition.
Collapse
|
Research Support, Non-U.S. Gov't |
17 |
50 |
18
|
Ramos Salas X, Alberga AS, Cameron E, Estey L, Forhan M, Kirk SFL, Russell-Mayhew S, Sharma AM. Addressing weight bias and discrimination: moving beyond raising awareness to creating change. Obes Rev 2017; 18:1323-1335. [PMID: 28994243 DOI: 10.1111/obr.12592] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/28/2017] [Revised: 06/18/2017] [Accepted: 06/26/2017] [Indexed: 01/05/2023]
Abstract
Weight discrimination is the unjust treatment of individuals because of their weight. There have been very few interventions to address weight discrimination, due in part to the lack of consensus on key messages and strategies. The objective of the third Canadian Weight Bias Summit was to review current evidence and move towards consensus on key weight bias and obesity discrimination reduction messages and strategies. Using a modified brokered dialogue approach, participants, including researchers, health professionals, policy makers and people living with obesity, reviewed the evidence and moved towards consensus on key messages and strategies for future interventions. Participants agreed to these key messages: (1) Weight bias and obesity discrimination should not be tolerated in education, health care and public policy sectors; (2) obesity should be recognized and treated as a chronic disease in health care and policy sectors; and (3) in the education sector, weight and health need to be decoupled. Consensus on future strategies included (1) creating resources to support policy makers, (2) using personal narratives from people living with obesity to engage audiences and communicate anti-discrimination messages and (3) developing a better clinical definition for obesity. Messages and strategies should be implemented and evaluated using consistent theoretical frameworks and methodologies.
Collapse
|
Review |
8 |
49 |
19
|
Cameron EL, Doty RL. Odor identification testing in children and young adults using the smell wheel. Int J Pediatr Otorhinolaryngol 2013; 77:346-50. [PMID: 23246420 DOI: 10.1016/j.ijporl.2012.11.022] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/01/2012] [Revised: 11/13/2012] [Accepted: 11/17/2012] [Indexed: 11/17/2022]
Abstract
OBJECTIVE Olfaction is important for nutrition, safety, and quality of life. Detecting smell loss in young children can be difficult, since many children with olfactory deficits do not recognize their problem and may even pretend to smell. The short attention span of some young children precludes testing with longer standardized olfactory tests. Currently there is a dearth of pediatric smell tests. In this study we evaluated the performance of 152 children and young adults on a game-like rotating "Smell Wheel" odor identification test. This forced-choice test, which can be self-administered, was designed to capture the child's imagination and to provide a standardized test measure with odors known to young children using a minimum number of trials. METHOD Thirty 4-5-year olds (10 female), 62 6-7-year olds (17 female), 30 10-11-year olds (18 female) and 30 18-19-year olds (15 female) were tested. Analysis of variance was used to assess the influences of sex and age on the test scores. RESULTS All participants completed the simple and rapid test protocol. Test performance and age-related changes analogous to those obtained using longer tests were observed. Test scores of participants who self-administered the test were equivalent to those for whom the test was administered by the experimenter. CONCLUSION Good compliance and olfactory test findings congruent with literature results were obtained using the Smell Wheel, suggesting that this test may be useful in assessing olfactory function in pediatric settings where attentional demands are compromised and test time is limited.
Collapse
|
|
12 |
48 |
20
|
Franck P, Cameron E, Good G, Rasplus JY, Oldroyd BP. Nest architecture and genetic differentiation in a species complex of Australian stingless bees. Mol Ecol 2004; 13:2317-31. [PMID: 15245404 DOI: 10.1111/j.1365-294x.2004.02236.x] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We investigated the taxonomic significance of nest shape and its putative role in speciation in Trigona (Heterotrigona) carbonaria and T. (H.) hockingsi, two sibling species of stingless bee species from eastern Australia. These species are primarily distinguished by their nest architecture, as in all other respects they are nearly identical. We genotyped 130 colonies from six locations in Queensland at 13 microsatellite loci together with 106 additional colonies from six other Indo-Pacific Trigona species. Whether they were present in allopatry or in sympatry, colonies that displayed the T. carbonaria or the T. hockingsi nest architecture could be unambiguously differentiated at the genetic level. However, T. hockingsi colonies were classifiable into two highly differentiated paraphyletic and geographically separate populations, one in northern and one in southern Queensland. These two populations probably belong to two distinct species, T. hockingsi and T. davenporti nov. sp. Our results suggest that nest architecture characters are relevant but not sufficient criteria to identify species in this group. Consequently, modifications of nest architecture are probably not of prime importance in the speciation process of Australian stingless bees, although nest architecture differences probably result from relatively simple mechanisms. The rare interspecific hybrid colonies detected did not display a nest with an intermediate form between T. hockingsi and T. carbonaria.
Collapse
|
|
21 |
46 |
21
|
Abstract
Many women report a heightened sense of smell during pregnancy. Accounts of these anecdotes have existed for over 100 years, but scientific evidence has been sparse and inconclusive. In this review, I examine the literature on olfactory perception during pregnancy including measures of self-report, olfactory thresholds, odor identification, intensity and hedonic ratings, and disgust. Support for a general decrease in olfactory thresholds (increase in sensitivity) is generally lacking. There is limited evidence that some suprathreshold measures of olfactory perception, such as hedonic ratings of odors, are affected by pregnancy, but these effects are idiosyncratic. In this review, I explore the hypotheses that have been put forth to explain changes in olfactory perception during pregnancy and provide suggestions for further research.
Collapse
|
Review |
11 |
46 |
22
|
Ciaramitaro VM, Cameron EL, Glimcher PW. Stimulus probability directs spatial attention: an enhancement of sensitivity in humans and monkeys. Vision Res 2001; 41:57-75. [PMID: 11163616 DOI: 10.1016/s0042-6989(00)00203-0] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
We examined whether improvements in sensory processing, defined as changes in sensitivity, could be elicited in a simple luminance discrimination task without eliciting concomitant changes in decision processing. To this end we developed a task, for use in both humans and monkeys, in which prior knowledge about where a discriminative stimulus was likely to appear (1) offered no decisional advantage in solving our task and (2) could be parametrically varied to yield a psychometric function. We found that if we parametrically varied the quality of prior knowledge, by increasing the probability, and thus the certainty, that a discriminative stimulus would appear at a particular location under these conditions, luminance discrimination improved for both human and monkey subjects. This improvement was correlated with an enhancement in sensory processing, but not with any systematic changes in decisional processing, as assessed by signal detection theory. These results suggest that (1) sensory processing and decision processing can be separated by task design and (2) systematic changes in prior knowledge about where a stimulus may appear can lead to systematic changes in sensitivity; providing a psychometric function for the influence of prior knowledge on perceptual sensitivity. Importantly, these results were obtained from both human and monkey subjects. Similar task designs could be used in physiological studies attempting to generate linking hypotheses between psychometric and neurometric functions, ultimately allowing changes in perceptual sensitivity to be linked to changes in an underlying neural substrate.
Collapse
|
|
24 |
43 |
23
|
Stewart M, Cameron E, Campbell M, McFarlane R, Toth S, Lang K, Onions D, Neil JC. Conditional expression and oncogenicity of c-myc linked to a CD2 gene dominant control region. Int J Cancer 1993; 53:1023-30. [PMID: 8473043 DOI: 10.1002/ijc.2910530628] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Over-expression of the c-myc gene is widely implicated in the genesis of lymphoid neoplasia, including tumours of the T-cell lineage. To study the effects of deregulated c-myc expression on T-cell development and oncogenesis, we sought to generate a transgenic mouse model in which c-myc expression was targeted specifically to the T-cell lineage. A plasmid construct containing a dominant control region (DCR) from the human CD2 locus linked 5' to the human c-myc gene was used to generate 2 lines of transgenic mice. Both strains developed thymic lymphoma at low frequency, but thymic development and peripheral T-cell numbers were otherwise apparently normal. Low tumour penetrance was consistent with the observed lack of stable CD2-myc transgene mRNA in tissues of healthy transgenic mice. In contrast, transgene RNA was detected in all malignant tumours as well as in early lymphomatous lesions. RNase protection analyses confirmed these findings and showed that the PI human c-myc promoter was active in all neoplastic tissues but not in the thymus or other tissues of healthy transgenic mice. Despite the low spontaneous tumour incidence, the presence of the transgene markedly and uniformly accelerated the onset of tumours after neonatal infection with Moloney murine leukaemia virus. All tumours were rearranged for T-cell receptor beta-chain genes and were of T-cell origin from their surface phenotype (Thy-1+, CD3+, CD4+/-, CD8+, sIg-). Virus-accelerated tumours contained clonal integrations of Moloney murine leukaemia virus, suggesting that proviral insertional mutagenesis may have played a role in tumour development. Analysis of several candidate myc-cooperating genes failed to reveal any rearrangements apart from a low frequency involving proviral insertion at the pim-1 locus. The CD2-myc mouse should therefore be a valuable system in screening for novel myc-collaborating genes involved in T-cell lymphoma.
Collapse
MESH Headings
- Animals
- Base Sequence
- Female
- Gene Expression/genetics
- Gene Rearrangement/genetics
- Gene Rearrangement, T-Lymphocyte/genetics
- Genes, Dominant/genetics
- Genes, Immunoglobulin/genetics
- Genes, myc/genetics
- Genetic Linkage/genetics
- Humans
- Leukemia, Experimental/genetics
- Leukemia, Experimental/microbiology
- Leukemia, T-Cell/genetics
- Leukemia, T-Cell/microbiology
- Lymphoma, T-Cell/genetics
- Lymphoma, T-Cell/microbiology
- Male
- Mice
- Mice, Inbred C57BL
- Mice, Inbred CBA
- Mice, Transgenic
- Molecular Sequence Data
- Moloney murine leukemia virus
- Phenotype
- Promoter Regions, Genetic/genetics
- T-Lymphocytes/physiology
- Thymus Gland/physiology
- Thymus Neoplasms/genetics
Collapse
|
|
32 |
43 |
24
|
|
|
53 |
40 |
25
|
Barber KE, Martineau M, Harewood L, Stewart M, Cameron E, Strefford JC, Rutherford S, Allen TD, Broadfield ZJ, Cheung KL, Harris RL, Jalali GR, Moorman AV, Robinson HM, Harrison CJ. Amplification of the ABL gene in T-cell acute lymphoblastic leukemia. Leukemia 2004; 18:1153-6. [PMID: 15057249 DOI: 10.1038/sj.leu.2403357] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
|
21 |
39 |