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Perlis RH, Lunz Trujillo K, Safarpour A, Quintana A, Simonson MD, Perlis J, Santillana M, Ognyanova K, Baum MA, Druckman JN, Lazer D. Community Mobility and Depressive Symptoms During the COVID-19 Pandemic in the United States. JAMA Netw Open 2023; 6:e2334945. [PMID: 37755830 PMCID: PMC10534266 DOI: 10.1001/jamanetworkopen.2023.34945] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/26/2023] [Accepted: 08/09/2023] [Indexed: 09/28/2023] Open
Abstract
Importance Marked elevation in levels of depressive symptoms compared with historical norms have been described during the COVID-19 pandemic, and understanding the extent to which these are associated with diminished in-person social interaction could inform public health planning for future pandemics or other disasters. Objective To describe the association between living in a US county with diminished mobility during the COVID-19 pandemic and self-reported depressive symptoms, while accounting for potential local and state-level confounding factors. Design, Setting, and Participants This survey study used 18 waves of a nonprobability internet survey conducted in the United States between May 2020 and April 2022. Participants included respondents who were 18 years and older and lived in 1 of the 50 US states or Washington DC. Main Outcome and Measure Depressive symptoms measured by the Patient Health Questionnaire-9 (PHQ-9); county-level community mobility estimates from mobile apps; COVID-19 policies at the US state level from the Oxford stringency index. Results The 192 271 survey respondents had a mean (SD) of age 43.1 (16.5) years, and 768 (0.4%) were American Indian or Alaska Native individuals, 11 448 (6.0%) were Asian individuals, 20 277 (10.5%) were Black individuals, 15 036 (7.8%) were Hispanic individuals, 1975 (1.0%) were Pacific Islander individuals, 138 702 (72.1%) were White individuals, and 4065 (2.1%) were individuals of another race. Additionally, 126 381 respondents (65.7%) identified as female and 65 890 (34.3%) as male. Mean (SD) depression severity by PHQ-9 was 7.2 (6.8). In a mixed-effects linear regression model, the mean county-level proportion of individuals not leaving home was associated with a greater level of depression symptoms (β, 2.58; 95% CI, 1.57-3.58) after adjustment for individual sociodemographic features. Results were similar after the inclusion in regression models of local COVID-19 activity, weather, and county-level economic features, and persisted after widespread availability of COVID-19 vaccination. They were attenuated by the inclusion of state-level pandemic restrictions. Two restrictions, mandatory mask-wearing in public (β, 0.23; 95% CI, 0.15-0.30) and policies cancelling public events (β, 0.37; 95% CI, 0.22-0.51), demonstrated modest independent associations with depressive symptom severity. Conclusions and Relevance In this study, depressive symptoms were greater in locales and times with diminished community mobility. Strategies to understand the potential public health consequences of pandemic responses are needed.
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Affiliation(s)
- Roy H. Perlis
- Massachusetts General Hospital, Boston
- Harvard Medical School, Boston, Massachusetts
| | - Kristin Lunz Trujillo
- Northeastern University, Boston, Massachusetts
- Harvard University, Cambridge, Massachusetts
| | - Alauna Safarpour
- Northeastern University, Boston, Massachusetts
- Harvard University, Cambridge, Massachusetts
| | - Alexi Quintana
- Northeastern University, Boston, Massachusetts
- Harvard University, Cambridge, Massachusetts
| | | | | | | | | | | | | | - David Lazer
- Northeastern University, Boston, Massachusetts
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Perlis RH, Lunz Trujillo K, Green J, Safarpour A, Druckman JN, Santillana M, Ognyanova K, Lazer D. Misinformation, Trust, and Use of Ivermectin and Hydroxychloroquine for COVID-19. JAMA Health Forum 2023; 4:e233257. [PMID: 37773507 PMCID: PMC10542734 DOI: 10.1001/jamahealthforum.2023.3257] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2023] [Accepted: 07/24/2023] [Indexed: 10/01/2023] Open
Abstract
Importance The COVID-19 pandemic has been notable for the widespread dissemination of misinformation regarding the virus and appropriate treatment. Objective To quantify the prevalence of non-evidence-based treatment for COVID-19 in the US and the association between such treatment and endorsement of misinformation as well as lack of trust in physicians and scientists. Design, Setting, and Participants This single-wave, population-based, nonprobability internet survey study was conducted between December 22, 2022, and January 16, 2023, in US residents 18 years or older who reported prior COVID-19 infection. Main Outcome and Measure Self-reported use of ivermectin or hydroxychloroquine, endorsing false statements related to COVID-19 vaccination, self-reported trust in various institutions, conspiratorial thinking measured by the American Conspiracy Thinking Scale, and news sources. Results A total of 13 438 individuals (mean [SD] age, 42.7 [16.1] years; 9150 [68.1%] female and 4288 [31.9%] male) who reported prior COVID-19 infection were included in this study. In this cohort, 799 (5.9%) reported prior use of hydroxychloroquine (527 [3.9%]) or ivermectin (440 [3.3%]). In regression models including sociodemographic features as well as political affiliation, those who endorsed at least 1 item of COVID-19 vaccine misinformation were more likely to receive non-evidence-based medication (adjusted odds ratio [OR], 2.86; 95% CI, 2.28-3.58). Those reporting trust in physicians and hospitals (adjusted OR, 0.74; 95% CI, 0.56-0.98) and in scientists (adjusted OR, 0.63; 95% CI, 0.51-0.79) were less likely to receive non-evidence-based medication. Respondents reporting trust in social media (adjusted OR, 2.39; 95% CI, 2.00-2.87) and in Donald Trump (adjusted OR, 2.97; 95% CI, 2.34-3.78) were more likely to have taken non-evidence-based medication. Individuals with greater scores on the American Conspiracy Thinking Scale were more likely to have received non-evidence-based medications (unadjusted OR, 1.09; 95% CI, 1.06-1.11; adjusted OR, 1.10; 95% CI, 1.07-1.13). Conclusions and Relevance In this survey study of US adults, endorsement of misinformation about the COVID-19 pandemic, lack of trust in physicians or scientists, conspiracy-mindedness, and the nature of news sources were associated with receiving non-evidence-based treatment for COVID-19. These results suggest that the potential harms of misinformation may extend to the use of ineffective and potentially toxic treatments in addition to avoidance of health-promoting behaviors.
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Affiliation(s)
- Roy H. Perlis
- Department of Psychiatry, Massachusetts General Hospital, Boston
- Department of Psychiatry, Harvard Medical School, Boston, Massachusetts
- Associate Editor, JAMA Network Open
| | - Kristin Lunz Trujillo
- Department of Political Science, Northeastern University, Boston, Massachusetts
- John F. Kennedy School of Government and Department of Government, Harvard University, Cambridge, Massachusetts
| | - Jon Green
- Department of Political Science, Northeastern University, Boston, Massachusetts
| | - Alauna Safarpour
- Department of Political Science, Northeastern University, Boston, Massachusetts
- John F. Kennedy School of Government and Department of Government, Harvard University, Cambridge, Massachusetts
| | - James N. Druckman
- Department of Political Science, Northwestern University, Evanston, Illinois
| | - Mauricio Santillana
- Department of Political Science, Northeastern University, Boston, Massachusetts
| | - Katherine Ognyanova
- Department of Communication, School of Communication and Information, Rutgers University, New Brunswick, New Jersey
| | - David Lazer
- Department of Political Science, Northeastern University, Boston, Massachusetts
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Abstract
Importance Little is known about the functional correlates of post-COVID-19 condition (PCC), also known as long COVID, particularly the relevance of neurocognitive symptoms. Objective To characterize prevalence of unemployment among individuals who did, or did not, develop PCC after acute infection. Design, Setting, and Participants This survey study used data from 8 waves of a 50-state US nonprobability internet population-based survey of respondents aged 18 to 69 years conducted between February 2021 and July 2022. Main Outcomes and Measures The primary outcomes were self-reported current employment status and the presence of PCC, defined as report of continued symptoms at least 2 months beyond initial month of symptoms confirmed by a positive COVID-19 test. Results The cohort included 15 308 survey respondents with test-confirmed COVID-19 at least 2 months prior, of whom 2236 (14.6%) reported PCC symptoms, including 1027 of 2236 (45.9%) reporting either brain fog or impaired memory. The mean (SD) age was 38.8 (13.5) years; 9679 respondents (63.2%) identified as women and 10 720 (70.0%) were White. Overall, 1418 of 15 308 respondents (9.3%) reported being unemployed, including 276 of 2236 (12.3%) of those with PCC and 1142 of 13 071 (8.7%) of those without PCC; 8229 respondents (53.8%) worked full-time, including 1017 (45.5%) of those with PCC and 7212 (55.2%) without PCC. In survey-weighted regression models excluding retired respondents, the presence of PCC was associated with a lower likelihood of working full-time (odds ratio [OR], 0.71 [95% CI, 0.63-0.80]; adjusted OR, 0.84 [95% CI, 0.74-0.96]) and with a higher likelihood of being unemployed (OR, 1.45 [95% CI, 1.22-1.73]; adjusted OR, 1.23 [95% CI, 1.02-1.48]). The presence of any cognitive symptom was associated with lower likelihood of working full time (OR, 0.70 [95% CI, 0.56-0.88]; adjusted OR, 0.75 [95% CI, 0.59-0.84]). Conclusions and Relevance PCC was associated with a greater likelihood of unemployment and lesser likelihood of working full time in adjusted models. The presence of cognitive symptoms was associated with diminished likelihood of working full time. These results underscore the importance of developing strategies to treat and manage PCC symptoms.
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Affiliation(s)
- Roy H Perlis
- Massachusetts General Hospital, Boston
- Department of Psychiatry, Harvard Medical School, Boston, Massachusetts
| | - Kristin Lunz Trujillo
- Northeastern University, Boston, Massachusetts
- Harvard University, Cambridge, Massachusetts
| | - Alauna Safarpour
- Northeastern University, Boston, Massachusetts
- Harvard University, Cambridge, Massachusetts
| | | | | | | | - David Lazer
- Northeastern University, Boston, Massachusetts
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Perlis RH, Trujillo KL, Safarpour A, Santillana M, Ognyanova K, Druckman J, Lazer D. Research Letter: Association between long COVID symptoms and employment status. medRxiv 2022:2022.11.17.22282452. [PMID: 36415464 PMCID: PMC9681048 DOI: 10.1101/2022.11.17.22282452] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Background Symptoms of Coronavirus-19 (COVID-19) infection persist beyond 2 months in a subset of individuals, a phenomenon referred to as long COVID, but little is known about its functional correlates and in particular the relevance of neurocognitive symptoms. Method We analyzed a previously-reported cohort derived from 8 waves of a nonprobability-sample internet survey called the COVID States Project, conducted every 4-8 weeks between February 2021 and July 2022. Primary analyses examined associations between long COVID and lack of full employment or unemployment, adjusted for age, sex, race and ethnicity, education, urbanicity, and region, using multiple logistic regression with interlocking survey weights. Results The cohort included 15,307 survey respondents ages 18-69 with test-confirmed COVID-19 at least 2 months prior, of whom 2,236 (14.6%) reported long COVID symptoms, including 1,027/2,236 (45.9%) reporting either 'brain fog' or impaired memory. Overall, 1,418/15,307 (9.3%) reported being unemployed, including 276/2,236 (12.3%) of those with long COVID and 1,142/13,071 (8.7%) of those without; 8,228 (53.8%) worked full-time, including 1,017 (45.5%) of those with long COVID and 7,211 (55.2%) without. In survey-weighted regression models, presence of long COVID was associated with being unemployed (crude OR 1.44, 95% CI 1.20-1.72; adjusted OR 1.23, 95% CI 1.02-1.48), and with lower likelihood of working full-time (crude OR 0.73, 95% CI 0.64-0.82; adjusted OR 0.79, 95% CI 0.70 -0.90). Among individuals with long COVID, the presence of cognitive symptoms - either brain fog or impaired memory - was associated with lower likelihood of working full time (crude OR 0.71, 95% CI 0.57-0.89, adjusted OR 0.77, 95% CI 0.61-0.97). Conclusion Long COVID was associated with a greater likelihood of unemployment and lesser likelihood of working full time in adjusted models. Presence of cognitive symptoms was associated with diminished likelihood of working full time. These results underscore the importance of developing strategies to respond to long COVID, and particularly the associated neurocognitive symptoms.
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Affiliation(s)
- Roy H. Perlis
- Massachusetts General Hospital, Boston, MA
- Harvard Medical School, Boston, MA
| | | | - Alauna Safarpour
- Northeastern University, Boston, MA
- Harvard University, Cambridge, MA
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Perlis RH, Santillana M, Ognyanova K, Safarpour A, Lunz Trujillo K, Simonson MD, Green J, Quintana A, Druckman J, Baum MA, Lazer D. Prevalence and Correlates of Long COVID Symptoms Among US Adults. JAMA Netw Open 2022; 5:e2238804. [PMID: 36301542 PMCID: PMC9614581 DOI: 10.1001/jamanetworkopen.2022.38804] [Citation(s) in RCA: 126] [Impact Index Per Article: 63.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
IMPORTANCE Persistence of COVID-19 symptoms beyond 2 months, or long COVID, is increasingly recognized as a common sequela of acute infection. OBJECTIVES To estimate the prevalence of and sociodemographic factors associated with long COVID and to identify whether the predominant variant at the time of infection and prior vaccination status are associated with differential risk. DESIGN, SETTING, AND PARTICIPANTS This cross-sectional study comprised 8 waves of a nonprobability internet survey conducted between February 5, 2021, and July 6, 2022, among individuals aged 18 years or older, inclusive of all 50 states and the District of Columbia. MAIN OUTCOMES AND MEASURES Long COVID, defined as reporting continued COVID-19 symptoms beyond 2 months after the initial month of symptoms, among individuals with self-reported positive results of a polymerase chain reaction test or antigen test. RESULTS The 16 091 survey respondents reporting test-confirmed COVID-19 illness at least 2 months prior had a mean age of 40.5 (15.2) years; 10 075 (62.6%) were women, and 6016 (37.4%) were men; 817 (5.1%) were Asian, 1826 (11.3%) were Black, 1546 (9.6%) were Hispanic, and 11 425 (71.0%) were White. From this cohort, 2359 individuals (14.7%) reported continued COVID-19 symptoms more than 2 months after acute illness. Reweighted to reflect national sociodemographic distributions, these individuals represented 13.9% of those who had tested positive for COVID-19, or 1.7% of US adults. In logistic regression models, older age per decade above 40 years (adjusted odds ratio [OR], 1.15; 95% CI, 1.12-1.19) and female gender (adjusted OR, 1.91; 95% CI, 1.73-2.13) were associated with greater risk of persistence of long COVID; individuals with a graduate education vs high school or less (adjusted OR, 0.67; 95% CI, 0.56-0.79) and urban vs rural residence (adjusted OR, 0.74; 95% CI, 0.64-0.86) were less likely to report persistence of long COVID. Compared with ancestral COVID-19, infection during periods when the Epsilon variant (OR, 0.81; 95% CI, 0.69-0.95) or the Omicron variant (OR, 0.77; 95% CI, 0.64-0.92) predominated in the US was associated with diminished likelihood of long COVID. Completion of the primary vaccine series prior to acute illness was associated with diminished risk for long COVID (OR, 0.72; 95% CI, 0.60-0.86). CONCLUSIONS AND RELEVANCE This study suggests that long COVID is prevalent and associated with female gender and older age, while risk may be diminished by completion of primary vaccination series prior to infection.
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Affiliation(s)
- Roy H. Perlis
- Department of Psychiatry, Massachusetts General Hospital, Boston
- Department of Psychiatry, Harvard Medical School, Boston, Massachusetts
| | - Mauricio Santillana
- Department of Political Science, Northeastern University, Boston, Massachusetts
| | - Katherine Ognyanova
- Department of Communication, School of Communication and Information, Rutgers University, New Brunswick, New Jersey
| | - Alauna Safarpour
- Department of Political Science, Northeastern University, Boston, Massachusetts
- John F. Kennedy School of Government and Department of Government, Harvard University, Cambridge, Massachusetts
| | - Kristin Lunz Trujillo
- Department of Political Science, Northeastern University, Boston, Massachusetts
- John F. Kennedy School of Government and Department of Government, Harvard University, Cambridge, Massachusetts
| | | | - Jon Green
- Department of Political Science, Northeastern University, Boston, Massachusetts
| | - Alexi Quintana
- Department of Political Science, Northeastern University, Boston, Massachusetts
| | - James Druckman
- Department of Political Science, Northwestern University, Evanston, Illinois
| | - Matthew A. Baum
- John F. Kennedy School of Government and Department of Government, Harvard University, Cambridge, Massachusetts
| | - David Lazer
- Department of Political Science, Northeastern University, Boston, Massachusetts
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Perlis RH, Simonson MD, Green J, Lin J, Safarpour A, Lunz Trujillo K, Quintana A, Chwe H, Della Volpe J, Ognyanova K, Santillana M, Druckman J, Lazer D, Baum MA. Prevalence of Firearm Ownership Among Individuals With Major Depressive Symptoms. JAMA Netw Open 2022; 5:e223245. [PMID: 35311961 PMCID: PMC8938748 DOI: 10.1001/jamanetworkopen.2022.3245] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
IMPORTANCE Both major depression and firearm ownership are associated with an increased risk for death by suicide in the United States, but the extent of overlap among these major risk factors is not well characterized. OBJECTIVE To assess the prevalence of current and planned firearm ownership among individuals with depression. DESIGN, SETTING, AND PARTICIPANTS Cross-sectional survey study using data pooled from 2 waves of a 50-state nonprobability internet survey conducted between May and July 7, 2021. Internet survey respondents were 18 years of age or older and were sampled from all 50 US states and the District of Columbia. MAIN OUTCOMES AND MEASURES Self-reported firearm ownership; depressive symptoms as measured by the 9-item Patient Health Questionnaire. RESULTS Of 24 770 survey respondents (64.6% women and 35.4% men; 5.0% Asian, 10.8% Black, 7.5% Hispanic, and 74.0% White; mean [SD] age 45.8 [17.5]), 6929 (28.0%) reported moderate or greater depressive symptoms; this group had mean (SD) age of 38.18 (15.19) years, 4587 were female (66.2%), and 406 were Asian (5.9%), 725 were Black (10.5%), 652 were Hispanic (6.8%), and 4902 were White (70.7%). Of those with depression, 31.3% reported firearm ownership (n = 2167), of whom 35.9% (n = 777) reported purchasing a firearm within the past year. In regression models, the presence of moderate or greater depressive symptoms was not significantly associated with firearm ownership (adjusted odds ratio [OR], 1.07; 95% CI, 0.98-1.17) but was associated with greater likelihood of a first-time firearm purchase during the COVID-19 pandemic (adjusted OR, 1.77; 95% CI, 1.56-2.02) and greater likelihood of considering a future firearm purchase (adjusted OR, 1.53; 95% CI, 1.23-1.90). CONCLUSIONS AND RELEVANCE In this study, current and planned firearm ownership was common among individuals with major depressive symptoms, suggesting a public health opportunity to address this conjunction of suicide risk factors.
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Affiliation(s)
- Roy H. Perlis
- Department of Psychiatry and Center for Quantitative Health, Massachusetts General Hospital, Boston
- Department of Psychiatry, Harvard Medical School, Boston, Massachusetts
| | - Matthew D. Simonson
- Network Science Institute and Institute for Qualitative Social Science, Northeastern University, Boston, Massachusetts
- Department of Political Science, University of Pennsylvania, Philadelphia
| | - Jon Green
- Network Science Institute and Institute for Qualitative Social Science, Northeastern University, Boston, Massachusetts
| | - Jennifer Lin
- Department of Political Science, Northwestern University, Evanston, Illinois
| | - Alauna Safarpour
- Network Science Institute and Institute for Qualitative Social Science, Northeastern University, Boston, Massachusetts
- Harvard Kennedy School of Government, Cambridge, Massachusetts
| | - Kristin Lunz Trujillo
- Network Science Institute and Institute for Qualitative Social Science, Northeastern University, Boston, Massachusetts
- Harvard Kennedy School of Government, Cambridge, Massachusetts
| | - Alexi Quintana
- Network Science Institute and Institute for Qualitative Social Science, Northeastern University, Boston, Massachusetts
| | - Hanyu Chwe
- Network Science Institute and Institute for Qualitative Social Science, Northeastern University, Boston, Massachusetts
| | | | - Katherine Ognyanova
- School of Communication and Information, Rutgers University, New Brunswick, New Jersey
| | - Mauricio Santillana
- Department of Pediatrics, Harvard Medical School, Cambridge, Massachusetts
- Department of Epidemiology, T.H. Chan School of Public Health, Harvard University, Cambridge, Massachusetts
- Computational Health Informatics Program, Boston Children’s Hospital, Boston, Massachusetts
| | - James Druckman
- Department of Political Science, Northwestern University, Evanston, Illinois
| | - David Lazer
- Network Science Institute and Institute for Qualitative Social Science, Northeastern University, Boston, Massachusetts
| | - Matthew A. Baum
- Harvard Kennedy School of Government, Cambridge, Massachusetts
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Kadkhoda Z, Safarpour A, Azmoodeh F, Adibi S, Khoshzaban A, Bahrami N. Histopathological Comparison between Bone Marrow- and Periodontium-derived Stem Cells for Bone Regeneration in Rabbit Calvaria. Int J Organ Transplant Med 2016; 7:9-18. [PMID: 26889369 PMCID: PMC4756260] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
BACKGROUND Periodontitis is an important oral disease. Stem cell therapy has found its way in treatment of many diseases. OBJECTIVE To evaluate the regenerative potential of periodontal ligament-derived stem cells (PDLSCs) and osteoblast differentiated from PDLSC in comparison with bone marrow-derived mesenchymal stem cells (BM-MSCs) and pre-osteoblasts in calvarial defects. METHODS After proving the existence of surface markers by flow cytometry, BM-MSCs were differentiated into osteoblasts. 5 defects were made on rabbit calvaria. 3 of them were first covered with collagen membrane and then with BM-MSCs, PDLSCs, and pre-osteoblasts. The 4(th) defect was filled with collagen membrane and the 5(th) one was served as control. After 4 weeks, histological (quantitative) and histomorphological (qualitative) surveys were performed. RESULTS Both cell lineages were positive for CD-90 cell marker, which was specifically related to stem cells. Alizarin red staining was done for showing mineral material. RT-PCR set up for the expression of Cbfa1 gene, BMP4 gene, and PGLAP gene, confirmed osteoblast differentiation. The findings indicated that although PDLSCs and pre-osteoblasts could be used for bone regeneration, the rate of regeneration in BM-MSCs-treated cavities was more significant (p<0.0001). CONCLUSION The obtained results are probably attributable to the effective micro-environmental signals caused by different bone types and the rate of cell maturation.
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Affiliation(s)
- Z. Kadkhoda
- Periodontology Department, Dental Faculty of Tehran University of Medical Sciences, Tehran, Iran
| | - A. Safarpour
- Periodontology Department, Dental Faculty of Tehran University of Medical Sciences, Tehran, Iran
| | - F. Azmoodeh
- Pathology Department, Imam Khomeini Hospital, Tehran University of Medical Sciences, Tehran, Iran
| | - S. Adibi
- Dental Research of Torabinejad Research Centre, Isfahan, Iran
| | - A. Khoshzaban
- Stem Cells Preparation Unit, Farabi Eye Hospital, Tehran University of Medical Sciences, Tehran, Iran
| | - N. Bahrami
- Oral and Maxillofacial Surgery Department, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran,Craniomaxillofacial Research Center, Tehran University of Medical Sciences, Tehran, Iran,Iranian Tissue Bank and Research Center, Tehran University of Medical Sciences, Tehran, Iran,CORRESPONDENCE: NAGHMEH BAHRAMI, ORAL AND MAXILLOFACIAL SURGERY DEPARTMENT, SCHOOL OF DENTISTRY, TEHRAN UNIVERSITY OF MEDICAL SCIENCES, NORTH AMIRABAD ST, TEHRAN, IRAN,E-mail:
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Thompson J, Pugh T, Guggenheimer K, Safarpour A, Christie A, Pel J, Chow S, Marziali A. Facilitated loading of horizontal gels using a capillary comb loader. Biotechniques 2003; 34:814-8. [PMID: 12703306 DOI: 10.2144/03344rr03] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Manual loading of samples into horizontal gels, such as the agarose gels commonly used for DNA fragment sizing and quantification, is laborious and prone to errors. Manual-loading times for highthroughput gels can reach 10 min/gel, and human error can result in incorrect identification of samples because of reverse loading or other errors in the loading process. To reduce gel-loading times and to improve reliability, a novel comb has been developed that uses glass capillaries and hydrostatic pressure to simplify sample loading from microplates. Accurate sample metering is ensured by the uniform length and volume of the capillaries. The loaded comb is placed in the gel boat over a pre-cast agarose gel, and buffer is added to a reservoir at the top of the comb. Once the buffer rises over the ends of the capillaries, the samples are pushed into the wells by hydrostatic pressure. This technique was successfully demonstrated for a 24-lane comb. This capillary comb loader reduces loading time, maintains well-to-well uniformity, and retains the same geometry and appearance of manually loaded bands, making this loading method compatible with existing downstream processes and software for subsequent analysis of the gel image.
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Affiliation(s)
- J Thompson
- University of British Columbia, Vancouver, BC, Canada
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