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A species-level trait dataset of bats in Europe and beyond. Sci Data 2023; 10:253. [PMID: 37137926 PMCID: PMC10156679 DOI: 10.1038/s41597-023-02157-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2022] [Accepted: 04/17/2023] [Indexed: 05/05/2023] Open
Abstract
Knowledge of species' functional traits is essential for understanding biodiversity patterns, predicting the impacts of global environmental changes, and assessing the efficiency of conservation measures. Bats are major components of mammalian diversity and occupy a variety of ecological niches and geographic distributions. However, an extensive compilation of their functional traits and ecological attributes is still missing. Here we present EuroBaTrait 1.0, the most comprehensive and up-to-date trait dataset covering 47 European bat species. The dataset includes data on 118 traits including genetic composition, physiology, morphology, acoustic signature, climatic associations, foraging habitat, roost type, diet, spatial behaviour, life history, pathogens, phenology, and distribution. We compiled the bat trait data obtained from three main sources: (i) a systematic literature and dataset search, (ii) unpublished data from European bat experts, and (iii) observations from large-scale monitoring programs. EuroBaTrait is designed to provide an important data source for comparative and trait-based analyses at the species or community level. The dataset also exposes knowledge gaps in species, geographic and trait coverage, highlighting priorities for future data collection.
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Effects of climate change on life‐history traits in hibernating mammals. Mamm Rev 2023. [DOI: 10.1111/mam.12308] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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3
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Rapid antigen testing by community health workers for detection of SARS-CoV-2 in Dhaka, Bangladesh: a cross-sectional study. BMJ Open 2022; 12:e060832. [PMID: 35649599 PMCID: PMC9160589 DOI: 10.1136/bmjopen-2022-060832] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Accepted: 05/10/2022] [Indexed: 12/02/2022] Open
Abstract
OBJECTIVE To evaluate the diagnostic performance and feasibility of rapid antigen testing for SARS-CoV-2 detection in low-income communities. DESIGN We conducted a cross-sectional community-based diagnostic accuracy study. Community health workers, who were trained and supervised by medical technicians, performed rapid antigen tests on symptomatic individuals, and up to two additional household members in their households and diagnostic results were calibrated against the gold standard RT-PCR. SETTING Low-income communities in Dhaka, Bangladesh. PARTICIPANTS Between 19 May 2021 and 11 July 2021, 1240 nasal and saliva samples were collected from symptomatic individuals and 993 samples from additional household members (up to two from one household). RESULTS The sensitivity of rapid antigen tests was 0.68 on nasal samples (95% CI 0.62 to 0.73) and 0.41 on saliva (95% CI 0.35 to 0.46), with specificity also higher on nasal samples (0.98, 95% CI 0.97 to 0.99) than saliva (0.87, 95% CI 0.85 to 0.90). Testing up to two additional household members increased sensitivity to 0.71 on nasal samples (95% CI 0.65 to 0.76), but reduced specificity (0.96, 95% CI 0.94 to 0.97). Sensitivity on saliva rose to 0.48 (95% CI 0.42 to 0.54) with two additional household members tested but remained lower than sensitivity on nasal samples. During the study period, testing in these low-income communities increased fourfold through the mobilisation of community health workers for sample collection. CONCLUSIONS Rapid antigen testing on nasal swabs can be effectively performed by community health workers yielding equivalent sensitivity and specificity to the literature. Household testing by community health workers in low-resource settings is an inexpensive approach that can increase testing capacity, accessibility and the effectiveness of control measures through immediately actionable results.
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Glucocorticoid levels predict subsequent social tactic in females of a facultatively social mammal. Funct Ecol 2020. [DOI: 10.1111/1365-2435.13744] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Myelination of the developing lateral olfactory tract and anterior commissure. J Comp Neurol 2018; 526:1843-1858. [PMID: 29665005 DOI: 10.1002/cne.24452] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2017] [Revised: 03/20/2018] [Accepted: 03/21/2018] [Indexed: 12/15/2022]
Abstract
Both the lateral olfactory tract (LOT) and anterior limb of the anterior commissure (AC) carry olfactory information. The LOT forms the projection from the olfactory bulb to the ipsilateral olfactory cortices, while the AC carries odor information across the midline to the contralateral olfactory cortex and bulb. The LOT and AC differ on a number of dimensions, including early development and functional onset. The present work, examining their myelination in mice, reveals additional important differences. For example, the LOT initiates myelination 3-4 days earlier than the AC, evidenced by both an earlier increase in myelin basic protein staining seen with immunohistochemistry and an earlier appearance of myelinated fibers using electron microscopy. While both exhibit a period of rapid myelination, it occurs 4-5 days earlier in the LOT than the AC. The tracts also respond differently to early sensory restriction. Unilateral naris occlusion from the day after birth to postnatal day 30 had no consistent effects on the AC but resulted in significantly thinner myelin sheaths relative to axon caliber in the LOT. Finally, the two tracts differ structurally (the LOT contains larger, more densely packed axons with significantly thicker myelin sheaths resulting in a conduction velocity that is more than twice as fast as the AC). The findings indicate that these two large, accessible tracts provide an important means for studying brain maturation due to basic differences in both the timing of their maturation and general organization.
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Corrigendum to “Weather influences feed intake and feed efficiency in a temperate climate” (J. Dairy Sci. 100:2240–2257). J Dairy Sci 2017; 100:5117. [DOI: 10.3168/jds.2017-100-6-5117] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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7
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Weather influences feed intake and feed efficiency in a temperate climate. J Dairy Sci 2017; 100:2240-2257. [PMID: 28109597 DOI: 10.3168/jds.2016-11047] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2016] [Accepted: 08/21/2016] [Indexed: 11/19/2022]
Abstract
A key goal for livestock science is to ensure that food production meets the needs of an increasing global population. Climate change may heighten this challenge through increases in mean temperatures and in the intensity, duration, and spatial distribution of extreme weather events, such as heat waves. Under high ambient temperatures, livestock are expected to decrease dry matter intake (DMI) to reduce their metabolic heat production. High yielding dairy cows require high DMI to support their levels of milk production, but this may increase susceptibility to heat stress. Here, we tested how feed intake and the rate of converting dry matter to milk (feed efficiency, FE) vary in response to natural fluctuations in weather conditions in a housed experimental herd of lactating Holstein Friesians in the United Kingdom. Cows belonged to 2 lines: those selected for high genetic merit for milk traits (select) and those at the UK average (control). We predicted that (1) feed intake and FE would vary with an index of temperature and humidity (THI), wind speed, and the number of hours of sunshine, and that (2) the effects of (1) would depend on the cows' genetic merit. Animals received a mixed ration, available ad libitum, from automatic feed measurement gates. Using >73,000 daily feed intake and FE records from 328 cows over 8 yr, we found that select cows produced more fat- and protein-corrected milk, and had higher DMI and FE than controls. Cows of both lines decreased DMI and fat- and protein-corrected milk but, importantly, increased FE as THI increased. This suggests that improvements in the efficiency of converting feed to milk may partially offset the costs of reduced milk yield owing to a warmer climate, at least under conditions of mild heat stress. The rate of increase in FE with THI was steeper in select cows than in controls, which raises the possibility that select cows use more effective coping tactics. This is, to our knowledge, the first longitudinal study on the effects of weather on FE. Understanding how weather influences feed intake and efficiency can help us to develop management and selection practices that optimize productivity under unfavorable weather conditions. This will be an important aspect of climate resilience in future.
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Variation in Reproductive Success Across Captive Populations: Methodological Differences, Potential Biases and Opportunities. Ethology 2016. [DOI: 10.1111/eth.12576] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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Alternative reproductive tactics in female striped mice: heavier females are more likely to breed solitarily than communally. J Anim Ecol 2015; 84:1497-508. [DOI: 10.1111/1365-2656.12431] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2014] [Accepted: 07/22/2015] [Indexed: 12/01/2022]
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Alternative reproductive tactics in female striped mice: Solitary breeders have lower corticosterone levels than communal breeders. Horm Behav 2015; 71:1-9. [PMID: 25828632 DOI: 10.1016/j.yhbeh.2015.03.004] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/27/2014] [Revised: 03/16/2015] [Accepted: 03/23/2015] [Indexed: 10/23/2022]
Abstract
Alternative reproductive tactics (ARTs), where members of the same sex and population show distinct reproductive phenotypes governed by decision-rules, have been well-documented in males of many species, but are less well understood in females. The relative plasticity hypothesis (RPH) predicts that switches between plastic ARTs are mediated by changes in steroid hormones. This has received much support in males, but little is known about the endocrine control of female ARTs. Here, using a free-living population of African striped mice (Rhabdomys pumilio) over five breeding seasons, we tested whether females following different tactics differed in corticosterone and testosterone levels, as reported for male striped mice using ARTs, and in progesterone and oestrogen, which are important in female reproduction. Female striped mice employ three ARTs: communal breeders give birth in a shared nest and provide alloparental care, returners leave the group temporarily to give birth, and solitary breeders leave to give birth and do not return. We expected communal breeders and returners to have higher corticosterone, owing to the social stress of group-living, and lower testosterone than solitary breeders, which must defend territories alone. Solitary breeders had lower corticosterone than returners and communal breeders, as predicted, but testosterone and progesterone did not differ between ARTs. Oestrogen levels were higher in returners (measured before leaving the group) than in communal and solitary breeders, consistent with a modulatory role. Our study demonstrates hormonal differences between females following (or about to follow) different tactics, and provides the first support for the RPH in females.
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Female but not male zebra finches adjust heat output in response to increased incubation demand. ACTA ACUST UNITED AC 2013; 217:1326-32. [PMID: 24363422 DOI: 10.1242/jeb.095323] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
In many incubating birds, heat transfer from parent to egg is facilitated by the brood patch, an area of ventral abdominal skin that becomes highly vascularised, swells and loses its down feathers around the time of laying. Only the female develops a brood patch in most passerine species, but males of some species can incubate and maintain the eggs at similar temperatures to females even without a brood patch. Here we used a novel application of infrared thermography to examine sex differences in parental care from a physiological perspective. Using incubating male and female zebra finches (Taeniopygia guttata), a species in which the male lacks a brood patch, we measured the surface temperature of the ventral plumage overlying the abdomen and a reference area that does not contact the eggs (thorax) twice per pair. In half of the pairs, clutch size was experimentally enlarged between the two sets of measurements to increase incubation demand. We found that the temperature differential between abdomen and thorax plumage was greater in females than in males, and that abdomen plumage was warmer after clutch enlargement than before in females but not in males. These findings are consistent with morphological sex differences in brood patch development and suggest that male and female zebra finches differ in the way they regulate abdomen versus general body surface temperature in response to variation in incubation demand.
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Feasibility and three months preliminary results of an RCT on the effect of Schroth exercises in adolescent idiopathic scoliosis (AIS). SCOLIOSIS 2013. [PMCID: PMC3675342 DOI: 10.1186/1748-7161-8-s1-o21] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/08/2023]
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Carry-over effects of male extra-pair copulation opportunity on biparental effort in zebra finches. Behav Ecol Sociobiol 2011. [DOI: 10.1007/s00265-011-1214-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Identifying the best surface topography parameters for detecting idiopathic scoliosis curve progression. Stud Health Technol Inform 2010; 158:78-82. [PMID: 20543404] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
There is no consensus on which surface topography (ST) parameters may be used to detect scoliosis progression. The sensitivity to change of common ST parameters has not yet been compared. The goal of this study was to determine which ST parameters are most sensitive to scoliosis progression in patients with adolescent idiopathic scoliosis (AIS) receiving conservative treatment. Fifty-eight subjects with AIS were included whose Cobb angle had progressed by at least 5 degrees during a 1 year interval. All had had ST scans and frontal radiographs at a 12 month interval at our clinic. Commonly used back-only ST parameters and contributing scores were derived by one evaluator. Standardized response mean (SRM) and 95% confidence intervals (CI) were calculated using the absolute value of the changes between baseline and follow-up to reflect change in deformity, independent of direction. Decompensation, cosmetic score, Deformity in the Axial Plane Index (DAPI), trunk rotation, Hump Sum, and lordosis angle were highly sensitive to scoliosis progression (SRM>0.8). Cosmetic score, Posterior Trunk Symmetry Index (POTSI), and kyphosis angle had significantly poorer SRM values than the Cobb angle. All other ST parameters had SRM estimates that did not differ significantly from the Cobb angle, suggesting that they have a similar ability to detect progression The ST measures that were most sensitive to detection of scoliosis progression in the frontal, transverse, and sagittal planes were decompensation, trunk rotation, and lordosis angle, respectively. Absolute changes in surface parameters representing either worsening or improvement externally could reflect worsening of the internal deformity. The majority of ST parameters are potentially sensitive to scoliosis progression.
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The effects of dietary protein restriction on chorda tympani nerve taste responses and terminal field organization. Neuroscience 2008; 157:329-39. [PMID: 18845228 DOI: 10.1016/j.neuroscience.2008.09.013] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2006] [Revised: 08/13/2008] [Accepted: 09/01/2008] [Indexed: 11/30/2022]
Abstract
Prenatal dietary sodium restriction produces profound developmental effects on rat functional taste responses and formation of neural circuits in the brainstem. Converging evidence indicates that the underlying mechanisms for these effects are related to a compromised nutritional state and not to direct stimulus-receptor interactions. We explored whether early malnourishment produces similar functional and structural effects to those seen following dietary sodium restriction by using a protein deficient, sodium replete diet. To determine if early dietary protein-restriction affects the development of the peripheral gustatory system, multi-fiber neurophysiological recordings were made from the chorda tympani nerve and anterograde track tracing of the chorda tympani nerve into the nucleus of the solitary tract (NTS) was accomplished in rats fed a protein-restricted or a control diet (6% and 20%, respectively). The dietary regimens began on embryonic day 7 and continued until rats were used for neurophysiological recordings (postnatal days (P) 35-50) or for chorda tympani terminal field labeling (P40-50). Responses to a concentration series of NaCl, sodium acetate, KCl, and to 0.50 M sucrose, 0.03 M quinine-HCl, and 0.01 N HCl revealed attenuated responses (30-60%) to sodium-specific stimuli in rats fed the 6% protein diet compared with those fed the 20% protein diet. Responses to all other stimuli were similar between groups. Terminal field volumes were nearly twofold larger in protein-restricted rats compared with controls, with the differences located primarily in the dorsal-caudal zone of the terminal field. These results are similar to the results seen previously in rats fed a sodium-restricted diet throughout pre- and postnatal development, suggesting that dietary sodium- and protein-restriction share similar mechanisms in altering gustatory development.
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Smart garment to help children improve posture. CONFERENCE PROCEEDINGS : ... ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL CONFERENCE 2008; 2006:5374-7. [PMID: 17946302 DOI: 10.1109/iembs.2006.259585] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Many of the aches and pains of adults are the result not of injuries, but of the long-term effects of distortions in posture or alignment. Postural kyphosis in adolescence may be one of the effects of poor standing and sitting habits. Kyphosis is an excessive rounding of the upper spine. A smart garment that can monitor and provide vibration feedback to children has been developed to investigate an alternative treatment possibility. Laboratory tests verified that the accuracy of the system was +/-2 degrees within the full 180 degrees range. A clinical trial has been conducted and it showed that the system can aid subjects to improve by 20% the proportion of time in a more balanced posture. The long term effect is still under investigation.
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20(S)-25-methoxyl-dammarane-3beta, 12beta, 20-triol, a novel natural product for prostate cancer therapy: activity in vitro and in vivo and mechanisms of action. Br J Cancer 2008; 98:792-802. [PMID: 18253123 PMCID: PMC2259179 DOI: 10.1038/sj.bjc.6604227] [Citation(s) in RCA: 101] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
We recently isolated 20(S)-25-methoxyl-dammarane-3β, 12β, 20-triol (25-OCH3-PPD), a natural product from Panax notoginseng, and demonstrated its cytotoxicity against a variety of cancer cells. Here we report the effects of this compound in vitro and in vivo on human prostate cancer cells, LNCaP (androgen-dependent) and PC3 (androgen-independent), in comparison with three structurally related ginsenosides, ginsenoside Rh2, ginsenoside Rg3, and 20(S)-protopanaxadiol. Of the four test compounds, 25-OCH3-PPD was most potent. It decreased survival, inhibited proliferation, induced apoptosis, and led to G1 cell cycle arrest in both cell lines. It also decreased the levels of proteins associated with cell proliferation (MDM2, E2F1, cyclin D1, and cdks 2 and 4) and increased or activated pro-apoptotic proteins (cleaved PARP, cleaved caspase-3, -8, and -9). In LNCaP cells, 25-OCH3-PPD inhibited the expression of the androgen receptor and prostate-specific antigen. Moreover, 25-OCH3-PPD inhibited the growth of prostate cancer xenograft tumours. Combining 25-OCH3-PPD with conventional chemotherapeutic agents or with radiation led to potent antitumour effects; tumour regression was almost complete following administration of 25-OCH3-PPD and either taxotere or gemcitabine. 25-OCH3-PPD also demonstrated low toxicity to noncancer cells and no observable toxicity in animals. In conclusion, our preclinical data indicate that 25-OCH3-PPD is a potential therapeutic agent against both androgen-dependent and androgen-independent prostate cancer.
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A wireless personal wearable network system to understand the biomechanics of orthotic for the treatment of scoliosis. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2008; 2008:3426-3429. [PMID: 19163445 DOI: 10.1109/iembs.2008.4649942] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
The wear tightness of an orthosis for the treatment of scoliosis varies greatly during daily activities. Currently, there is no commercially available product that can monitor force distribution inside the brace and the time that the othosis is worn during daily activities. Subjective feeling is the most commonly used method. To provide an objective measure, a battery-powered wireless personal wearable network system is developed. This system consists of up to 16 wireless force loggers and a USB ZigBee dongle. Each logger contains a force sensor and a wireless unit. The whole system records how much time the orthosis has been used and how loads distribute inside the orthoses. Laboratory tests have been performed; the maximum force measurement error is +/-0.02N and the resolution is 0.1N. The average power consumption of the system is 0.3mW/h and thus a single AAA-sized alkaline battery is able to support the power for 6 months.
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Isolation, structural determination, and evaluation of the biological activity of 20(S)-25-methoxyl-dammarane-3beta, 12beta, 20-triol [20(S)-25-OCH3-PPD], a novel natural product from Panax notoginseng. Med Chem 2007; 3:51-60. [PMID: 17266624 DOI: 10.2174/157340607779317508] [Citation(s) in RCA: 81] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Ginseng has been used extensively for medicinal purposes, with suggested utility for indications as diverse as diabetes, cardiovascular disease and cancer. Herein we report the discovery and characterization of 20(S)-25-OCH3-PPD, a ginsenoside that inhibits growth and survival of cancer cells. The novel dammarane triterpene sapogenin (C31H56O4; molecular weight 492) was isolated from the total hydrolyzed saponins extracted from the leaves of Panax notoginseng using conventional and reverse-phase silica gel chromatography. Based on physicochemical characteristics and NMR data, the compound was identified as 20(S)-25-OCH3-PPD. The biological activities of 20(S)-25-OCH3-PPD and its known analogs, 20(S)-PPD and Rg3, were evaluated in 12 human cancer cell lines. In all cell lines, the order of cytotoxicity of the test compounds was 20(S)-25-OCH3-PPD >> 20(S)-PPD >> Rg3. 20(S)-25-OCH3-PPD also induced apoptosis and cell cycle arrest in the G1 phase, and inhibited proliferation in breast cancer cell lines, demonstrating its potent biological effects. In regard to cytotoxicity, the IC50 values of 20(S)-25-OCH3-PPD for most cell lines were in the lower microM range, a 5-15-fold greater cytotoxicity relative to 20(S)-PPD and a 10-100-fold increase over Rg3. These findings suggest a structure-activity relationship among dammarane-type sapogenins. The data presented here may provide a basis for the future development of 20(S)-25-OCH3-PPD as a novel anti-cancer agent.
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Ribosomal protein S7 as a novel modulator of p53-MDM2 interaction: binding to MDM2, stabilization of p53 protein, and activation of p53 function. Oncogene 2007; 26:5029-37. [PMID: 17310983 DOI: 10.1038/sj.onc.1210327] [Citation(s) in RCA: 207] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
As a major negative regulator of p53, the MDM2 oncogene plays an important role in carcinogenesis and tumor progression. MDM2 promotes p53 proteasomal degradation and negatively regulates p53 function. The mechanisms by which the MDM2-p53 interaction is regulated are not fully understood, although several MDM2-interacting molecules have recently been identified. To search for novel MDM2-binding partners, we screened a human prostate cDNA library by the yeast two-hybrid assay using full-length MDM2 protein as the bait. Among the candidate proteins, ribosomal protein S7 was identified and confirmed as a novel MDM2-interacting protein. Herein, we demonstrate that S7 binds to MDM2, in vitro and in vivo, and that the interaction between MDM2 and S7 leads to modulation of MDM2-p53 binding by forming a ternary complex among MDM2, p53 and S7. This results in the stabilization of p53 protein through abrogation of MDM2-mediated p53 ubiquitination. Consequently, S7 overexpression increases p53 transactivational activities, induces apoptosis, and inhibits cell proliferation. The identification of S7 as a novel MDM2-interacting partner contributes to elucidation of the complex regulation of the MDM2-p53 interaction and has implications in cancer prevention and therapy.
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Abstract
There is considerable controversy regarding the effectiveness of orthotic treatment for patients with adolescent idiopathic scoliosis. Most researchers believe that, to be effective, the orthosis must be worn as prescribed for both compliance and tightness. Compliance is the time the brace is worn relative to the prescribed time. A battery-powered microcomputer system was developed to monitor and maintain the loads exerted by orthoses used to treat children with spinal deformities during daily living. This system not only records how well and for how much time the brace has been used, but also helps patients to ensure that the brace is being worn at the prescribed tightness. Laboratory tests were performed, and five patients used the system for four weeks. The patients reported that the system helped them to wear the orthoses correctly and comfortably. The time that the patients wore the orthoses at the prescribed tightness level increased from 53 +/- 9% during the monitoring period (first 2 weeks) to 68 +/- 14% during the automatic adjustment period (last 2 weeks).
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Correlation between quantity and quality of orthosis wear and treatment outcomes in adolescent idiopathic scoliosis. Prosthet Orthot Int 2004; 28:49-54. [PMID: 15171578 DOI: 10.3109/03093640409167925] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Orthotic treatment is the most commonly used non-surgical treatment method for adolescent idiopathic scoliosis (AIS). This study determined whether treatment outcome correlates with how often and how well children with AIS wear their orthoses. Eighteen (18) subjects (3M, 15F) who were diagnosed with idiopathic scoliosis and had worn their orthoses from 6 months up to 1 year participated in this study. All subjects were prescribed Boston braces to be worn full time (23 hrs/day). Twelve (12) subjects who completed their brace treatment were included in the data analysis. Three (3) treatment outcomes were classified as improvement, no change and deterioration. The quality of the brace wear was assessed by how often the brace was worn with zero force, below 80%, between 80 to 120%, and above 120% of the load level prescribed in the clinic. The quantity of brace wear was determined by how many hours per day they wore their brace. Subjects who wear their braces tighter and for more hours per day seem to have better outcomes.
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Abstract
A database system with Bluetooth wireless connectivity has been developed so that scoliosis clinics can be run more efficiently and data can be mined for research studies without significant increases in equipment cost. The wireless database system consists of a Bluetooth-enabled laptop or PC and a Bluetooth-enabled handheld personal data assistant (PDA). Each patient has a profile in the database, which has all of his or her clinical history. Immediately prior to the examination, the orthopaedic surgeon selects a patient's profile from the database and uploads that data to the PDA over a Bluetooth wireless connection. The surgeon can view the entire clinical history of the patient while in the examination room and, at the same time, enter in any new measurements and comments from the current examination. After seeing the patient, the surgeon synchronises the newly entered information with the database wirelessly and prints a record for the chart. This combination of the database and the PDA both improves efficiency and accuracy and can save significant time, as there is less duplication of work, and no dictation is required. The equipment required to implement this solution is a Bluetooth-enabled PDA and a Bluetooth wireless transceiver for the PC or laptop.
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Abstract
An electronically instrumented rod rotator has been developed to monitor forces and moments applied by surgeons during the derotation manoeuver to correct spinal curvature. This instrumented rod rotator consisted of an inclinometer and two pairs of strain gauges, with all the support circuitry. The strain gauge and the inclinometer data were sampled with a data-acquisition system, and the results were displayed in real time. The device was calibrated in the laboratory and used on seven subjects. The precision of the load measurement of this device was +/- 5 N in the range of 5-65N. The distance between the middle of the rod rotator handle to the rod position was 0.21 m. The maximum loads applied by the surgeon during seven surgeries were from 22 to 57N, with a torque (force x distance) from 4.6 to 12 Nm.
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Abstract
The three-dimensional nature of scoliosis, coupled with changes due to natural history or treatment, is often difficult to quantify and visualise. A difference map was developed to compare the sequential surface topography of subjects over their treatment period. Three-dimensional surface maps representing patients' trunk surfaces were captured with a laser scanner. Patient surface maps from two clinic visits were matched using a manual best-fit technique that accounted for growth and positioning. The surfaces were subtracted, generating a colour-coded three-dimensional difference map displaying the surface changes. The difference maps were compared with known clinical measures, indicating good agreement (78% specific) with the clinical parameters in detecting change. Full agreement or agreement with the clinical parameters occurred in the surgical, brace and no treatment groups: 76%, 80% and 85%, respectively. A difference index (average of the absolute value of differences on a point-by-point basis) was calculated from the difference map, enabling quantification of change. The difference index, with zero being a perfect match, averaged 5 +/- 1 for repeated measures 7 +/- 2 for subjects deemed to have no change, 9 +/- 2 for subjects with slight change, and 14 +/- 2 for subjects with significant change. The difference map showed the extent and location of changes and is a useful tool for assessing surface topography changes.
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Abstract
The efficacy of orthotic treatment for children with abnormal spinal curvature has been hampered by the lack of comprehensive information about wear characteristics. A battery-powered microcomputer system was developed to monitor loads exerted by orthoses used to treat children with spinal deformities during daily living. The system not only records how well the orthosis has been used, but also helps to ensure that the orthosis is being worn as prescribed. Data acquisition is controlled by a microcontroller and can be programmed to have sample intervals ranging from 1 second to 1 hour. Low power control circuitry is designed so that the system can be operated by a battery. In a preliminary study, 16 subjects (3M, 13F) used this system from 1 to 16 days (9.3 +/- 5.0) with the prescribed hours between 16 to 23 hours (22.3 +/- 1.3). This study demonstrated the feasibility of the approach, and that this device may increase the understanding of orthotic mechanics, and may help patients to wear their orthoses in a better way.
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Evaluation of a laser scanner for surface topography. Stud Health Technol Inform 2002; 88:90-4. [PMID: 15456009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/30/2023]
Abstract
A Minolta VIVID 700 portable non-contact 3D laser scanner was evaluated on 15 subjects with idiopathic scoliosis. The 3D map was compared to two structured light pattern (lines and dots) techniques to determine the reliability, ease of use, speed, and quality. The parameters used for the clinical assessment of scoliosis were measured twice for the Minolta and light projection systems. The edges of the image and areas where occlusion typically occur were examined. The absolute distance in calculated depth between adjacent points was examined to determine errors. The Minolta system and the dot pattern produced regular grids of points. The light projection pattern produced an irregular grid, with more resolution along the video line and less resolution between projected lines, resulted in a somewhat jagged appearance of the surface map. The Minolta system was less sensitive to edge effects, occlusion, and sharp transitions of depth. The comparison of clinical parameters showed good results between repetitions but moderate results between techniques.
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Local energy as a measure of back symmetry in scoliosis. Stud Health Technol Inform 2002; 91:194-8. [PMID: 15457722] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/30/2023]
Abstract
The Cobb angle has been the most commonly used method in measuring the severity of scoliosis and its progression. However, in recent years a number of researchers have chosen to monitor scoliosis by examining the severity of the surface deformity resulting from the scoliosis. Each of these approaches has been limited by errors introduced in manual location of landmarks. Scoliosis results in an asymmetry of the back. It would be very desirable to have a computer-based method of measuring this asymmetry. This paper investigates the use of wavelets and the concept of local energy to measure asymmetry associated with scoliosis. The local energy model uses wavelet theory to obtain information about shading and boundaries of objects in an image. Edges and sharp discontinuities are areas of high local energy in an image. Features such as scapular prominence, shoulder edges, waist creases and other anomalies that contribute to the scoliotic back asymmetry have high local energy. A preliminary study was completed to determine if this approach was applicable to measurement of back asymmetry. Two-dimensional local energy images were created from photographs of the backs of patients with scoliosis. The local energy was integrated across each image and a left-to right line of symmetry was calculated. This line of symmetry was then correlated with the scoliotic score developed by our group. This technique shows promise of providing an automatic method of measuring scoliosis progression.
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Image coding technique for 3-D back reconstruction. Stud Health Technol Inform 2002; 88:186-90. [PMID: 15456029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/30/2023]
Abstract
This work investigated the use of coded-line patterns to improve image correspondence and 3D reconstruction. The objective was to define an optimum structured light pattern to facilitate the construction of topographic maps of the trunks of scoliosis patients. The system consisted of stereo CCD television cameras, a slide projector to create the coded-line pattern and a computer with video acquisition card. The optimum pattern in terms of generating correct results with minimum computing time was a line pattern consisting of 6 groupings of 3-level grey lines. This chosen pattern was investigated using known 3D objects to determine the effectiveness, resolution and computational time to correlate stereo images. The selected structured light pattern consisted of a repeated pattern of white (W), grey (G) and black (B) lines. Each line was 4mm wide on the back surface. The pattern consisted of 6 groups of 3 lines, WBG WGB GWB GBW BGW BWG. Using known 3D models of a section of a cylinder, a plate with steps and a ramp-like object; the coded line system was tested under typical clinical lighting conditions. For the 3D test objects, errors in correspondence occurred in 2-4 % of stereo pixels. The processing time varied from 10-12 minutes. The 3D resolution obtained was 4mm.
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Computer modelling of hooks for use as intra-operative force sensors. Stud Health Technol Inform 2002; 88:350-5. [PMID: 15456060] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/30/2023]
Abstract
There are a number of forces applied during scoliosis surgery, the magnitude and direction of which remains unknown. There is little literature concerning the in vivo distribution of forces along the spine. Computer modelling (ANSYS) was used to investigate the possibility of using an instrumented hook to intra-operatively measure the antero-posterior and distraction/compression forces applied by the surgeon during corrective scoliosis surgery. Three hook designs were evaluated based on specific design criteria. ANSYS provided the preliminary analysis to determine the strain distribution in these hooks. One design, the "membrane" design, was selected and a prototype was manufactured. Preliminary tests demonstrate that this prototype will be able to differentiate between the four major forces applied during the surgical correction.
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31
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Assessing changes in three dimensional scoliotic deformities with difference maps. Stud Health Technol Inform 2002; 91:178-83. [PMID: 15457719] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/30/2023]
Abstract
Topographical difference maps were used to compare the trunk surfaces of subjects over the course of their treatment. Three-dimensional points representing the trunk surfaces were aligned accounting for growth and positioning. A goodness-of-fit score was calculated and a color map used to display trunk surface changes. Fifty-one successive subjects were assessed with difference maps. Two subjects each had 10 repetitions taken on the same day to assess reliability. A blinded observer used a five-point scale that extended from full agreement to full disagrment to judge the maps according to the extent and location of changes. The observations were compared to clinical measures mapped onto the same scale by another blinded observer. Goodness of fit for repeated measures averaged 5 +/- 1, for subjects deemed to have no change 7 +/- 2, for subjects with slight change 9 +/- 2, and 14 +/- 2 for subjects with significant change. Judges were in full agreement or in agreemnt with forty of the fifty-one subjects (78%) and in slight disagreement with the remaining eleven. When the cohort was subdivided in surgical, brace and no treatment groups, the judges were in full agreement or in agreement 76%, 80%, and 85% respectively. The difference map provides a qualitative and quantitative measure of how the trunk surface has changed as a whole.
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32
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Is the Boston brace mechanically effective in AIS? Stud Health Technol Inform 2002; 91:378-82. [PMID: 15457760] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/30/2023]
Abstract
The application of three-point loading is thought to be the essential basis for effective bracing of adolescent idiopathic scoliosis. Care is taken to ensure that active pressure pad is located to provide maximum support to the apex of the scoliosis while minimizing its lordosising effect. Paradoxically, while cited as an essential factor in the design of braces, there is no consensus as to the importance of such loading to the clinical effectiveness of braces. It may be that braces are effective but that they are effective for reasons unrelated to mechanics. There are few studies that link brace mechanics and change in spinal alignment. Optimal bracing for AIS requires a much better understanding of the role of the mechanical support of braces used to treat AIS. Sixteen subjects, 3 males and 13 females, were participated to this study to determine the correlation between quantity and quality of brace wear and treatment outcomes in AIS. This study showed that the target force levels set for the active pad in braces prescribed for the treatment of AIS vary considerably and that brace applies the desired load 25% of the prescribed time.
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Validation of a two- to three-dimensional registration algorithm for aligning preoperative CT images and intraoperative fluoroscopy images. Med Phys 2001; 28:1024-32. [PMID: 11439472 DOI: 10.1118/1.1373400] [Citation(s) in RCA: 91] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
We present a validation of an intensity based two- to three-dimensional image registration algorithm. The algorithm can register a CT volume to a single-plane fluoroscopy image. Four routinely acquired clinical data sets from patients who underwent endovascular treatment for an abdominal aortic aneurysm were used. Each data set was comprised of two intraoperative fluoroscopy images and a preoperative CT image. Regions of interest (ROI) were drawn around each vertebra in the CT and fluoroscopy images. Each CT image ROI was individually registered to the corresponding ROI in the fluoroscopy images. A cross validation approach was used to obtain a measure of registration consistency. Spinal movement between the preoperative and intraoperative scene was accounted for by using two fluoroscopy images. The consistency and robustness of the algorithm when using two similarity measures, pattern intensity and gradient difference, was investigated. Both similarity measures produced similar results. The consistency values were rotational errors below 0.74 degree and in-plane translational errors below 0.90 mm. These errors approximately relate to a two-dimensional projection error of 1.3 mm. The failure rate was less than 8.3% for three of the four data sets. However, for one of the data sets a much larger failure rate (28.5%) occurred.
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Community interdisciplinary education to promote partnerships in family violence prevention. FAMILY & COMMUNITY HEALTH 2001; 24:15-27. [PMID: 11275568 DOI: 10.1097/00003727-200104000-00005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Family violence is a major social and health problem in the United States. Educational approaches are needed that help professionals and communities develop more effective skills to work with families and communities. This article describes a statewide, interdisciplinary, community-based educational program for professionals and paraprofessionals and a 6-month post-evaluation. Participants reported knowledge and skill development in assessment and interventions, improved use of violence prevention data for planning and interventions, and increased community partnerships and collaborations. Recommendations address violence prevention leadership, funding, infrastructure, interdisciplinary professional education, greater community awareness, and policy development.
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35
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Stereo augmented reality in the surgical microscope. Stud Health Technol Inform 2001; 62:102-8. [PMID: 10538337] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
Abstract
We present an augmented reality system that allows surgeons to view features from preoperative radiological images accurately overlaid in stereo in the optical path of a surgical microscope. The purpose of the system is to show the surgeon structures beneath the viewed surface in the correct 3-D position. The technical challenges are registration, tracking, calibration and visualisation. For patient registration, or alignment to preoperative images, we use bone-implanted markers and a dental splint is used for patient tracking. Both microscope and patient are tracked by an optical localiser. Calibration uses an accurately manufactured object with high contrast circular markers which are identified automatically. All ten camera parameters are modelled as a bivariate polynomial function of zoom and focus. The overall system has a theoretical overlay accuracy of better than 1 mm. Implementations of the system have been tested on seven patients. Recent measurements in the operating room conformed to our accuracy predictions. For visualisation the system has been implemented on a graphics workstation to enable high frame rates with a variety of rendering schemes. Several issues of 3-D depth perception remain unsolved, but early results suggest that perception of structures in the correct 3-D position beneath the viewed surface is possible.
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36
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Abstract
Radiological images are increasingly being used in healthcare and medical research. There is, consequently, widespread interest in accurately relating information in the different images for diagnosis, treatment and basic science. This article reviews registration techniques used to solve this problem, and describes the wide variety of applications to which these techniques are applied. Applications of image registration include combining images of the same subject from different modalities, aligning temporal sequences of images to compensate for motion of the subject between scans, image guidance during interventions and aligning images from multiple subjects in cohort studies. Current registration algorithms can, in many cases, automatically register images that are related by a rigid body transformation (i.e. where tissue deformation can be ignored). There has also been substantial progress in non-rigid registration algorithms that can compensate for tissue deformation, or align images from different subjects. Nevertheless many registration problems remain unsolved, and this is likely to continue to be an active field of research in the future.
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38
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Retinoic acid (RA) receptor transcriptional activation correlates with inhibition of 12-O-tetradecanoylphorbol-13-acetate-induced ornithine decarboxylase (ODC) activity by retinoids: a potential role for trans-RA-induced ZBP-89 in ODC inhibition. Int J Cancer 2001; 91:8-21. [PMID: 11149424 DOI: 10.1002/1097-0215(20010101)91:1<8::aid-ijc1007>3.0.co;2-h] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Evaluation of retinoic acid receptor (RAR) subtype-selective alpha and gamma agonists and antagonists and a retinoid X receptor (RXR) class-selective agonist for efficacy at inhibiting both induction of ornithine decarboxylase (ODC) by the tumor promoter 12-O-tetradecanoylphorbol-13-acetate (TPA) in mouse epidermis and rat tracheal epithelial cells and the appearance of papillomas in mouse epidermis treated in the 2-stage tumor initiation-promotion model indicated that (i) RXR class-selective transcriptional agonists, such as MM11246, were not involved in ODC inhibition; (ii) RAR-selective agonists that induce gene transcription from RA-responsive elements (RAREs) were active at low concentrations; (iii) RAR-selective antagonists that bind RARs and inhibit AP-1 activation on the collagenase promoter but do not activate RAREs to induce gene transcription were less effective inhibitors; and (iv) RARgamma-selective retinoid agonists were more effective inhibitors of TPA-induced ODC activity than RARalpha-selective agonists. These results suggest that RARE activation has a more important role in inhibition of ODC activity than RXR activation or AP-1 inhibition and that RARgamma-selective agonists would be the most useful inhibitors of epithelial cell proliferation induced by tumor promoters. The natural retinoid all-trans-RA induced expression of transcription factor ZBP-89, which represses activation of the GC box in the ODC promoter by the transcription factor Sp1.
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MESH Headings
- 9,10-Dimethyl-1,2-benzanthracene
- Animals
- Antineoplastic Agents/pharmacology
- Blotting, Northern
- Blotting, Western
- Carcinogens
- Cell Survival/drug effects
- Collagenases/genetics
- DNA-Binding Proteins/physiology
- Dose-Response Relationship, Drug
- Epidermis/metabolism
- Epithelial Cells/metabolism
- Female
- HeLa Cells
- Humans
- Mice
- Mice, Hairless
- Neoplasms, Experimental/metabolism
- Ornithine Decarboxylase Inhibitors
- Papilloma/metabolism
- Promoter Regions, Genetic
- Protein Binding
- Protein Kinases/metabolism
- RNA, Messenger/metabolism
- Rats
- Receptors, Retinoic Acid/chemistry
- Receptors, Retinoic Acid/metabolism
- Response Elements
- Retinoic Acid Receptor alpha
- Retinoids/metabolism
- Retinoids/pharmacology
- Tetradecanoylphorbol Acetate/pharmacology
- Time Factors
- Trachea/metabolism
- Transcription Factor AP-1/antagonists & inhibitors
- Transcription Factors/physiology
- Transcription, Genetic
- Transcriptional Activation
- Transfection
- Ultraviolet Rays
- Retinoic Acid Receptor gamma
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39
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Lack of functional and morphological susceptibility of the greater superficial petrosal nerve to developmental dietary sodium restriction. Chem Senses 2000; 25:719-27. [PMID: 11114150 DOI: 10.1093/chemse/25.6.719] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Restriction of dietary sodium during gestation has major effects on taste function and anatomy in the offspring. The chorda tympani nerve of offspring that are maintained on sodium-reduced chow throughout life (NaDep) has reduced neurophysiological responses to sodium and altered morphology of its terminal field in the nucleus of the solitary tract. There are many anatomical and physiological similarities between the chorda tympani nerve that innervates taste buds on the anterior tongue and the greater superficial petrosal nerve (GSP) that innervates taste buds on the palate. To determine if the GSP is similarly susceptible to the effects of dietary sodium restriction, the present study examined neurophysiological responses and the terminal field of the GSP in NaDep and control rats. Neurophysiological responses of the GSP to a variety of sodium and non-sodium stimuli did not differ between NaDep and control rats. Furthermore, the volume and shape of the GSP terminal field in the nucleus of the solitary tract did not differ between the groups. Therefore, despite the high degree of functional and anatomical correspondence between the chorda tympani nerve and the GSP, the GSP does not appear to be susceptible to the effects of lifelong dietary sodium restriction.
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40
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Design and evaluation of a system for microscope-assisted guided interventions (MAGI). IEEE TRANSACTIONS ON MEDICAL IMAGING 2000; 19:1082-93. [PMID: 11204846 DOI: 10.1109/42.896784] [Citation(s) in RCA: 87] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
The problem of providing surgical navigation using image overlays on the operative scene can be split into four main tasks--calibration of the optical system; registration of preoperative images to the patient; system and patient tracking, and display using a suitable visualization scheme. To achieve a convincing result in the magnified microscope view a very high alignment accuracy is required. We have simulated an entire image overlay system to establish the most significant sources of error and improved each of the stages involved. The microscope calibration process has been automated. We have introduced bone-implanted markers for registration and incorporated a locking acrylic dental stent (LADS) for patient tracking. The LADS can also provide a less-invasive registration device with mean target error of 0.7 mm in volunteer experiments. These improvements have significantly increased the alignment accuracy of our overlays. Phantom accuracy is 0.3-0.5 mm and clinical overlay errors were 0.5-1.0 mm on the bone fiducials and 0.5-4 mm on target structures. We have improved the graphical representation of the stereo overlays. The resulting system provides three-dimensional surgical navigation for microscope-assisted guided interventions (MAGI).
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Celecoxib inhibits N-butyl-N-(4-hydroxybutyl)-nitrosamine-induced urinary bladder cancers in male B6D2F1 mice and female Fischer-344 rats. Cancer Res 2000; 60:5599-602. [PMID: 11059745] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
Epidemiological studies have shown that nonsteroidal anti-inflammatory drugs (NSAIDs) may have a role in the prevention of human cancers. A number of preclinical studies have also suggested that inhibition of cyclooxygenase (COX) with NSAIDs has an anticancer effect in animal models of colon, urinary bladder, skin, and breast. In these studies, we evaluated the COX-2 inhibitor celecoxib in two rodent models of urinary bladder cancer. Male B6D2F1 mice treated with N-butyl-N-(4-hydroxybutyl)-nitrosamine (OH-BBN) developed transitional and squamous cell urinary bladder cancers, many of which grew rapidly and caused substantial morbidity that required sacrifice of the mice. Groups of mice received various daily doses of celecoxib in the diet (1250, 500, or 200 mg/kg of diet) beginning 7 days before the initiation of 12 weekly doses of OH-BBN. Mice were checked weekly for the presence of palpable urinary bladder masses. The study was terminated at 8 months following the initial treatment with OH-BBN. The percentage of mice with large palpable bladder lesions, which necessitated sacrifice of the mice, was 40% in the OH-BBN control group. In contrast, only 10% of all celecoxib-treated mice required sacrifice before the scheduled termination of the experiment, implying that all three doses of celecoxib inhibited the formation of large palpable lesions. Celecoxib did not significantly alter the incidence of preneoplastic bladder lesions, but did dose-dependently decrease the total number of urinary bladder cancers/mouse, palpable plus microscopic, by 77, 57, and 43% at dosages of 1250, 500, and 200 mg of celecoxib/kg of diet, respectively. In the second model, female Fischer-344 rats were administered OH-BBN twice/week for a period of 8 weeks. After 8 months, all rats developed preneoplastic lesions, whereas roughly 60% of the rats developed relatively small urinary bladder cancers. Rats were treated continually with celecoxib in the diet (500 or 1000 mg/kg of diet) beginning either 1 week prior to the initial OH-BBN treatment or beginning 1 week following the last OH-BBN treatment. Neither celecoxib treatment regimen significantly altered the number of preneoplastic lesions. Whereas celecoxib treatment initiated prior to OH-BBN administration decreased cancer incidence roughly 65%, celecoxib treatment initiated beginning 1 week after the last dose of OH-BBN profoundly decreased cancer incidence (>95%). Celecoxib did not alter the body weights of the mice or rats, or cause other signs of toxicity at any of the doses studied. Taken together these results demonstrate that: (a) celecoxib effectively inhibits tumor growth and enhances survival in the mouse model of urinary bladder cancer; and (b) celecoxib profoundly inhibits development of urinary bladder cancers in the rat model even when administered following the last dose of OH-BBN. Clinical trials will be necessary to determine whether COX-2 inhibitors will provide a clinical benefit in human bladder cancer.
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MESH Headings
- Animals
- Anticarcinogenic Agents/pharmacology
- Butylhydroxybutylnitrosamine/toxicity
- Carcinogens/antagonists & inhibitors
- Carcinogens/toxicity
- Carcinoma, Squamous Cell/chemically induced
- Carcinoma, Squamous Cell/enzymology
- Carcinoma, Squamous Cell/prevention & control
- Carcinoma, Transitional Cell/chemically induced
- Carcinoma, Transitional Cell/enzymology
- Carcinoma, Transitional Cell/prevention & control
- Celecoxib
- Cyclooxygenase 2
- Cyclooxygenase 2 Inhibitors
- Cyclooxygenase Inhibitors/pharmacology
- Disease Models, Animal
- Dose-Response Relationship, Drug
- Female
- Isoenzymes/antagonists & inhibitors
- Male
- Mice
- Mice, Inbred C57BL
- Mice, Inbred DBA
- Organ Specificity
- Precancerous Conditions/chemically induced
- Precancerous Conditions/enzymology
- Precancerous Conditions/prevention & control
- Prostaglandin-Endoperoxide Synthases
- Pyrazoles
- Rats
- Rats, Inbred F344
- Sulfonamides/pharmacology
- Urinary Bladder Neoplasms/chemically induced
- Urinary Bladder Neoplasms/enzymology
- Urinary Bladder Neoplasms/prevention & control
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Development of rat chorda tympani sodium responses: evidence for age-dependent changes in global amiloride-sensitive Na(+) channel kinetics. J Neurophysiol 2000; 84:1531-44. [PMID: 10980025 DOI: 10.1152/jn.2000.84.3.1531] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
In rat, chorda tympani nerve taste responses to Na(+) salts increase between roughly 10 and 45 days of age to reach stable, mature magnitudes. Previous evidence from in vitro preparations and from taste nerve responses using Na(+) channel blockers suggests that the physiological basis for this developmental increase in gustatory Na(+) sensitivity is the progressive addition of functional, Na(+) transduction elements (i.e., amiloride-sensitive Na(+) channels) to the apical membranes of fungiform papilla taste receptor cells. To avoid potential confounding effects of pharmacological interventions and to permit quantification of aggregate Na(+) channel behavior using a kinetic model, we obtained chorda tympani nerve responses to NaCl and sodium gluconate (NaGlu) during receptive field voltage clamp in rats aged from 12-14 to 60 days and older (60+ days). Significant, age-dependent increases in chorda tympani responses to these stimuli occurred as expected. Importantly, apical Na(+) channel density, estimated from an apical Na(+) channel kinetic model, increased monotonically with age. The maximum rate of Na(+) response increase occurred between postnatal days 12-14 and 29-31. In addition, estimated Na(+) channel affinity increased between 12-14 and 19-23 days of age, i.e., on a time course distinct from that of the maximum rate of Na(+) response increase. Finally, estimates of the fraction of clamp voltage dropped across taste receptor apical membranes decreased between 19-23 and 29-31 days of age for NaCl but remained stable for NaGlu. The stimulus dependence of this change is consistent with a developmental increase in taste bud tight junctional Cl(-) ion permeability that lags behind the developmental increase in apical Na(+) channel density. A significant, indirect anion influence on apical Na(+) channel properties was present at all ages tested. This influence was evident in the higher apparent apical Na(+) channel affinities obtained for NaCl relative to NaGlu. This stimulus-dependent modulation of apical Na(+) channel apparent affinity relies on differences in the transepithelial potentials between NaCl and NaGlu. These originate from differences in paracellular anion permeability but act also on the driving force for Na(+) through apical Na(+) channels. Detection of such an influence on taste depends fundamentally on the preservation of taste bud polarity and on a direct measure of sensory function, such as the response of primary afferents.
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Abstract
We present a system for surgical navigation using stereo overlays in the operating microscope aligned to the operative scene. This augmented reality system provides 3D information about nearby structures and offers a significant advancement over pointer-based guidance, which provides only the location of one point and requires the surgeon to look away from the operative scene. With a previous version of this system, we demonstrated feasibility, but it became clear that to achieve convincing guidance through the magnified microscope view, a very high alignment accuracy was required. We have made progress with several aspects of the system, including automated calibration, error simulation, bone-implanted fiducials and a dental attachment for tracking. We have performed experiments to establish the visual display parameters required to perceive overlaid structures beneath the operative surface. Easy perception of real and virtual structures with the correct transparency has been demonstrated in a laboratory and through the microscope. The result is a system with a predicted accuracy of 0.9 mm and phantom errors of 0.5 mm. In clinical practice errors are 0.5-1.5 mm, rising to 2-4 mm when brain deformation occurs.
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44
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Sources of error in comparing functional magnetic resonance imaging and invasive electrophysiological recordings. J Neurosurg 2000; 93:214-23. [PMID: 10930006 DOI: 10.3171/jns.2000.93.2.0214] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECT Several authors have recently reported studies in which they aim to validate functional magnetic resonance (fMR) imaging against the accepted gold standard of invasive electrophysiological monitoring. The authors have conducted a similar study, and in this paper they identify and quantify two characteristics of these data that can make such a comparison problematic. METHODS Eight patients in whom surgery for epilepsy was performed and five healthy volunteers underwent fMR imaging to localize the part of the sensorimotor cortex responsible for hand movement. In the patient group subdural electrode mats were subsequently implanted to identify eloquent regions of the brain and the epileptogenic zone. The fMR imaging data were processed to correct for motion during the study and then registered with a postimplantation computerized tomography (CT) scan on which the electrodes were visible. The motion during imaging in the two groups studied, and the deformation of the brain between the preoperative images and postoperative scans were measured. The patients who underwent epilepsy surgery moved significantly more during fMR imaging experiments than healthy volunteers performing the same motor task. This motion had a particularly increased out-of-plane component and was significantly more correlated with the stimulus than in the volunteers. This motion was especially increased when the patients were performing a task on the side affected by the lesion. The additional motion is hard to correct and substantially degrades the quality of the resulting fMR images, making it a much less reliable technique for use in these patients than in others. Also, the authors found that after electrode implantation, the brain surface can shift more than 10 mm relative to the skull compared with its preoperative location, substantially degrading the accuracy of the comparison of electrophysiological measurements made in the deformed brain and fMR studies obtained preoperatively. CONCLUSIONS These two findings indicate that studies of this sort are currently of limited use for validating fMR imaging and should be interpreted with care. Additional image analysis research is necessary to solve the problems caused by patients' motion and brain deformation.
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45
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Abstract
Subject motion during diffusion-weighted interleaved echo-planar imaging causes k-space offsets which lead to irregular sampling in the phase-encode direction. For each image, the k-space shifts are monitored using 2D navigator echoes, and are shown to lead to a frequent violation of the Nyquist condition when an ungated sequence is used on seven subjects. Combining data from four repeat acquisitions allows the Nyquist condition to be satisfied in all but 1% of images. Reconstruction of the irregularly-sampled data can be performed using a matrix inversion technique. The repeated acquisitions make the inversion more stable and additionally improve the signal-to-noise ratio. The resultant isotropic diffusion-weighted images and average apparent diffusion coefficient (ADC) maps show high resolution and enable clear localization of a stroke lesion. Residual ADC artifacts with a slow spatial variation are observed and assumed to originate from non-rigid pulsatile brain motion. Magn Reson Med 44:101-109, 2000.
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46
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Feasibility study of magnetic resonance imaging-guided intranasal flexible microendoscopy. COMPUTER AIDED SURGERY : OFFICIAL JOURNAL OF THE INTERNATIONAL SOCIETY FOR COMPUTER AIDED SURGERY 2000; 2:264-75. [PMID: 9484587 DOI: 10.1002/(sici)1097-0150(1997)2:5<264::aid-igs2>3.0.co;2-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Interventional magnetic resonance imaging (MRI) offers potential advantages over conventional interventional modalities such as X-ray fluoroscopy, ultrasonography, and computed tomography (CT). In particular, it does not use ionizing radiation, can provide high-quality images, and allows acquisition of oblique sections. We have carried out a feasibility study on the use of interventional MRI to track a flexible microendoscope in the paranasal sinuses. In this cadaver study, high-speed MRI was used to track a passive marker attached to the end of the endoscope. Automatic image registration algorithms were used to transfer the coordinates of the endoscope tip into the preoperative MRI and CT images, enabling us to display the position of the endoscope in reformatted orthogonal views or in a rendered view of the preoperative images. The endoscope video images were digitized and could be displayed alongside an approximately aligned, rendered preoperative image. Intraoperative display was provided in the scanner room by means of an liquid crystal display (LCD) projector. We estimate the accuracy of the endoscope tracking to be approximately 2 mm.
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47
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AcouStick: An optically tracked A-mode ultrasonography system for registration in image-guided neurosurgery. Stereotact Funct Neurosurg 2000; 72:143-4. [PMID: 10853067 DOI: 10.1159/000029715] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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48
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Neuron/target matching between chorda tympani neurons and taste buds during postnatal rat development. JOURNAL OF NEUROBIOLOGY 2000; 43:98-106. [PMID: 10756070] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
During postnatal development, a relationship is established between the size of individual taste buds and number of innervating neurons. To determine whether rearrangement of neurons that innervate taste buds establishes this relationship, we labeled single taste buds at postnatal day 10 (P10) and again at either P15, P20, or P40 with retrograde fluorescent neuronal tracers. The number of single- and double-labeled geniculate ganglion cells was counted, and the respective taste bud volumes were measured for the three groups of rats. The current study replicates findings from an earlier report demonstrating that the larger the taste bud, the more geniculate ganglion cells that innervate it. This relationship between taste bud size and number of innervating neurons is not apparent until P40, when taste bud size reaches maturity. These findings are extended here by demonstrating that the number of neurons that innervate taste buds at P10, when taste bud size is small and relatively homogeneous, predicts the size that the respective taste bud will become at maturity. Moreover, while there is some neural rearrangement of taste bud innervation from P10 to P40, rearrangement does not impact the relationship between taste bud size and innervating neurons. That is, the neurons that maintain contact with taste buds from P10 through P40 accurately predict the mature taste bud size. Therefore, the size of the mature taste bud is determined by P10 and relates to the number of sensory neurons that innervate it at that age and the number of neurons that maintain contact with it throughout the first 40 days of postnatal development.
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49
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Behavioral taste responses of developmentally NaCl-restricted rats to various concentrations of NaCl. Behav Neurosci 2000; 114:437-41. [PMID: 10832804] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
The behavioral taste responses of developmentally NaCl-restricted rats were examined with a brief-exposure taste test. Neurophysiological and morphological alterations have been reported in rats whose dietary sodium is restricted during pre- and postnatal development, yet there exists little data discerning their behavioral response to tastants. Control and developmentally NaCl-restricted rats were maintained on a low-NaCl diet and trained to lick from individually presented sipper tubes. Each subject received 4 days of testing on various NaCl concentrations. Results indicate that developmentally NaCl-restricted rats have dramatically increased lick rates to NaCl solutions. These responses are likely due to some combination of factors including (a) numbers and type of active chorda tympani fibers, (b) compensatory responses to NaCl-solutions from other nerves of the oral cavity, and (c) increased sensitivity of central taste systems to NaCl.
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50
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Voxel similarity measures for 3-D serial MR brain image registration. IEEE TRANSACTIONS ON MEDICAL IMAGING 2000; 19:94-102. [PMID: 10784281 DOI: 10.1109/42.836369] [Citation(s) in RCA: 116] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
We have evaluated eight different similarity measures used for rigid body registration of serial magnetic resonance (MR) brain scans. To assess their accuracy we used 33 clinical three-dimensional (3-D) serial MR images, with deformable extradural tissue excluded by manual segmentation and simulated 3-D MR images with added intensity distortion. For each measure we determined the consistency of registration transformations for both sets of segmented and unsegmented data. We have shown that of the eight measures tested, the ones based on joint entropy produced the best consistency. In particular, these measures seemed to be least sensitive to the presence of extradural tissue. For these data the difference in accuracy of these joint entropy measures, with or without brain segmentation, was within the threshold of visually detectable change in the difference images.
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