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Habarth-Morales TE, Davis HD, Duca A, Salinero LK, Chandragiri S, Rios-Diaz AJ, Broach RB, Caterson EJ, Swanson JW. Factors associated with late surgical correction of craniosynostosis: A decade-long review of the United States nationwide readmission database. J Craniomaxillofac Surg 2024; 52:585-590. [PMID: 38448339 DOI: 10.1016/j.jcms.2024.02.016] [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] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2023] [Accepted: 02/11/2024] [Indexed: 03/08/2024] Open
Abstract
Late-repair craniosynostosis (LRC), defined as craniosynostosis surgery beyond 1 year of age, is often associated with increased complexity and potential complications. Our study analyzed data from the 2010-2019 Nationwide Readmissions Database to investigate patient factors related to LRC. Of 10 830 craniosynostosis repair cases, 17% were LRC. These patients were predominantly from lower-income families and had more comorbidities, indicating that socioeconomic status could be a significant contributor. LRC patients were typically treated at teaching hospitals and privately owned investment institutions. Our risk-adjusted analysis revealed that LRC patients were more likely to belong to the lowest-income quartile, receive treatment at privately owned investment hospitals, and use self-payment methods. Despite these challenges, the hospital stay duration did not significantly differ between the two groups. Interestingly, LRC patients faced a higher predicted mean total cost compared with those who had surgery before turning 1. This difference in cost did not translate to a longer length of stay, further emphasizing the complexity of managing LRC. These findings highlight the urgent need for earlier intervention in craniosynostosis cases, particularly in lower-income communities. The medical community must strive to improve early diagnosis and treatment strategies in order to mitigate the socioeconomic and health disparities observed in LRC patients.
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Affiliation(s)
- Theodore E Habarth-Morales
- Division of Plastic Surgery, Department of Surgery, University of Pennsylvania, Philadelphia, PA, USA; Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA, USA.
| | - Harrison D Davis
- Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA, USA; Lewis Katz School of Medicine, Temple University, Philadelphia, PA, USA
| | - Aviana Duca
- Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA, USA
| | - Lauren K Salinero
- Division of Plastic, Reconstructive, and Oral Surgery, Department of Surgery, Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Shreyas Chandragiri
- Division of Plastic Surgery, Department of Surgery, University of Pennsylvania, Philadelphia, PA, USA; Division of Plastic Surgery, Department of Surgery, Nemours Children's Health, Wilmington, DE, USA
| | - Arturo J Rios-Diaz
- Division of Plastic Surgery, Department of Surgery, University of Pennsylvania, Philadelphia, PA, USA
| | - Robyn B Broach
- Division of Plastic Surgery, Department of Surgery, University of Pennsylvania, Philadelphia, PA, USA
| | - Edward J Caterson
- Division of Plastic Surgery, Department of Surgery, Nemours Children's Health, Wilmington, DE, USA
| | - Jordan W Swanson
- Division of Plastic Surgery, Department of Surgery, University of Pennsylvania, Philadelphia, PA, USA; Division of Plastic, Reconstructive, and Oral Surgery, Department of Surgery, Children's Hospital of Philadelphia, Philadelphia, PA, USA
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Davis HD, Habarth-Morales TE, Messa CA, Broach RB, Lin IC. Extracorporeal Membrane Oxygenation-Associated Compartment Syndrome: Review of a National Database. J Surg Res 2024; 298:94-100. [PMID: 38593603 DOI: 10.1016/j.jss.2024.02.012] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Revised: 01/28/2024] [Accepted: 02/16/2024] [Indexed: 04/11/2024]
Abstract
INTRODUCTION Extracorporeal membrane oxygenation (ECMO)-associated compartment syndrome (CS) is a rare complication seen in critically ill patients. The epidemiology and management of ECMO-associated CS in the upper extremity (UE) and lower extremity (LE) are poorly defined in the literature. We sought to determine the epidemiology and characterize treatment and outcomes of UE-CS compared to LE-CS in the setting of ECMO therapy. METHODS Adult patients undergoing ECMO therapy were identified in the Nationwide Readmission Database (2015-2019) and followed up for 6 months. Patients were stratified based on UE-CS versus LE-CS. Primary outcomes were fasciotomy and amputation. All-cause mortality and length of stay were also collected. Risk-adjusted modeling was performed to determine patient- and hospital-level factors associated with differences in the management UE-CS versus LE-CS while controlling for confounders. RESULTS A total of 24,047 cases of ECMO during hospitalization were identified of which 598 were complicated by CS. Of this population, 507 cases were in the LE (84.8%), while 91 (15.5%) were in the UE. After multivariate analysis, UE-CS patients were less likely to undergo fasciotomy (50.5 vs. 70.9; P = 0.013) and were less likely to undergo amputation of the extremity (3.3 vs. 23.7; P = 0.001) although there was no difference in mortality (58.4 vs. 65.4; P = 0.330). CONCLUSIONS ECMO patients with CS experience high mortality and morbidity. UE-CS has lower rates of fasciotomy and amputations, compared to LE-CS, with similar mortality. Further studies are needed to elucidate the reasons for these differences.
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Affiliation(s)
- Harrison D Davis
- Division of Plastic Surgery, Department of Surgery, University of Pennsylvania, Philadelphia, Pennsylvania; Lewis Katz School of Medicine, Temple University, Philadelphia, Pennsylvania.
| | - Theodore E Habarth-Morales
- Division of Plastic Surgery, Department of Surgery, University of Pennsylvania, Philadelphia, Pennsylvania; Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, Pennsylvania
| | - Charles A Messa
- Division of Plastic Surgery, Department of Surgery, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Robyn B Broach
- Division of Plastic Surgery, Department of Surgery, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Ines C Lin
- Division of Plastic Surgery, Department of Surgery, University of Pennsylvania, Philadelphia, Pennsylvania; Department of Orthopaedic Surgery, University of Pennsylvania, Philadelphia, Pennsylvania
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Niu EF, Honig SE, Wang KE, Amro C, Davis HD, Habarth-Morales TE, Broach RB, Fischer JP. Obesity as a Risk Factor in Cosmetic Abdominal Body Contouring: A Systematic Review and Meta-Analysis. Aesthetic Plast Surg 2023:10.1007/s00266-023-03602-w. [PMID: 37644187 DOI: 10.1007/s00266-023-03602-w] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Accepted: 08/07/2023] [Indexed: 08/31/2023]
Abstract
BACKGROUND The incidence of obesity is on the rise around the globe. Outside of the massive weight loss (MWL) patient population, knowledge of risk factors associated with abdominal body contouring (BC) is limited. This systematic review and meta-analysis assesses the impact of obesity has on cosmetic abdominal BC outcomes. METHODS A systematic review conducted in accordance with PRISMA 2020 was done. PubMed, Embase, Scopus, and COCHRANE databases were reviewed under search syntax "obesity," "abdominoplasty," "panniculectomy," and "body contouring" for articles. Cosmetic was defined as abdominoplasty or panniculectomy outside the context of MWL. Obesity was defined as BMI ≥ 30 kg/m2. Studies reporting postoperative outcomes with less than 50% of their population involving MWL patients were included. Postoperative outcomes were assessed by pooled analysis and meta-analysis. RESULTS Of 3088 initial studies, 16 met inclusion criteria, and nine were used for pooled and meta-analysis. Meta-analysis demonstrated that obesity was associated with more seromas (OR 1.45, 1.06-1.98, p = 0.02), hematomas (OR 2.21, 1.07-4.57, p = 0.03), and total surgical site occurrences (OR 1.99, 1.30-3.04, p = 0.0016). There was no significant difference in odds of any other complications. Analysis by obesity class showed no significant increase in odds in seromas or wound dehiscence. CONCLUSIONS This review demonstrates obesity increased odds of postoperative complications following cosmetic abdominal BC. However, risk of complications does not continue to increase with higher obesity class. A BMI ≥ 30 kg/m2 should not be a strict contraindication to cosmetic abdominal BC. Instead, plastic surgeons should evaluate patients on a case-by-case basis. LEVEL OF EVIDENCE III This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .
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Affiliation(s)
- Ellen F Niu
- Division of Plastic Surgery, Department of Surgery, University of Pennsylvania Health System, PCAM South Pavilion 14th Floor, 3400 Civic Center Boulevard, Philadelphia, PA, 19104, USA.
| | - Stephanie E Honig
- Division of Plastic Surgery, Department of Surgery, University of Pennsylvania Health System, PCAM South Pavilion 14th Floor, 3400 Civic Center Boulevard, Philadelphia, PA, 19104, USA
| | - Katherine E Wang
- Renaissance School of Medicine at Stony, Brook University, Stony Brook, NY, USA
| | - Chris Amro
- Division of Plastic Surgery, Department of Surgery, University of Pennsylvania Health System, PCAM South Pavilion 14th Floor, 3400 Civic Center Boulevard, Philadelphia, PA, 19104, USA
| | - Harrison D Davis
- Division of Plastic Surgery, Department of Surgery, University of Pennsylvania Health System, PCAM South Pavilion 14th Floor, 3400 Civic Center Boulevard, Philadelphia, PA, 19104, USA
| | - Theodore E Habarth-Morales
- Division of Plastic Surgery, Department of Surgery, University of Pennsylvania Health System, PCAM South Pavilion 14th Floor, 3400 Civic Center Boulevard, Philadelphia, PA, 19104, USA
| | - Robyn B Broach
- Division of Plastic Surgery, Department of Surgery, University of Pennsylvania Health System, PCAM South Pavilion 14th Floor, 3400 Civic Center Boulevard, Philadelphia, PA, 19104, USA
| | - John P Fischer
- Division of Plastic Surgery, Department of Surgery, University of Pennsylvania Health System, PCAM South Pavilion 14th Floor, 3400 Civic Center Boulevard, Philadelphia, PA, 19104, USA
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Akinbiyi T, Kozak GM, Davis HD, Barrette LX, Rios-Diaz AJ, Maxwell R, Tilahun ED, Jones JA, Broach RB, Butler PD. Contemporary treatment of keloids: A 10-year institutional experience with medical management, surgical excision, and radiation therapy. Am J Surg 2020; 221:689-696. [PMID: 32878694 DOI: 10.1016/j.amjsurg.2020.07.035] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Revised: 06/29/2020] [Accepted: 07/27/2020] [Indexed: 11/27/2022]
Abstract
INTRODUCTION We evaluate a single center's, decade-long experience utilizing 3 approaches to keloid treatment: corticosteroid medical management (MM), surgical excision (SE), and surgical excision + radiation therapy (SE + RT). STUDY DESIGN Patients undergoing keloid treatment were identified (2008-2017). Outcomes were symptomatology/cosmesis for MM, and recurrence and complications for SE and SE + RT. Logistic regression was used to determine factors associated with recurrence and complications. RESULTS 284 keloids (95 MM, 94 SE, 95 S E + RT) corresponded to patients with a median age of 39.1 (IQR: 26.1-53), 68.1% Black, and followed-up for 15.4 months (IQR: 5.6-30.7). For MM, 84.6% and 72.5% reported improvement in cosmesis and symptoms, respectively. SE and SE + RT recurrence were 37.2 and 37.9%, respectively. In adjusted analyses, higher radiation doses were associated with decreased recurrence whereas male gender (OR 3.3) and postoperative steroids (OR 9.5) were associated with increased recurrence (p < 0.01). There were more complications in the SE + RT group. CONCLUSIONS MM resulted in at least some improvement. Recurrence rates after SE and SE + RT were similar. Female sex is protective, race does not affect outcomes.
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Affiliation(s)
- Takintope Akinbiyi
- Division of Plastic Surgery, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Geoffrey M Kozak
- Division of Plastic Surgery, University of Pennsylvania, Philadelphia, PA, 19104, USA; Department of Surgery, Thomas Jefferson University, Philadelphia, PA, 19107, USA
| | - Harrison D Davis
- Division of Plastic Surgery, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Louis-Xavier Barrette
- Division of Plastic Surgery, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Arturo J Rios-Diaz
- Division of Plastic Surgery, University of Pennsylvania, Philadelphia, PA, 19104, USA; Department of Surgery, Thomas Jefferson University, Philadelphia, PA, 19107, USA
| | - Russell Maxwell
- Department of Radiation Oncology, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Estifanos D Tilahun
- Division of Plastic Surgery, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Joshua A Jones
- Department of Radiation Oncology, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Robyn B Broach
- Division of Plastic Surgery, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Paris D Butler
- Division of Plastic Surgery, University of Pennsylvania, Philadelphia, PA, 19104, USA.
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Abstract
Several synthetic nucleoside analogues, including AZT(RETROVIR), ddC (HIVID), ddI (VIDEX), and d4T (ZERIT), are currently being used in the treatment of HIV infection. Unfortunately, in clinical use the appearance of severe and sometimes debilitating peripheral neuropathy and pain has been associated with the long-term use of several of these drugs (i.e., ddC, ddI and d4T), although not with AZT. To date, standard pre-clinical animal toxicity studies have failed to reveal any adverse neurologic effects of these compounds. However, previously reported preliminary findings suggest that ddC may alter several neuro-behavioral parameters (including locomotor activity, acoustic startle responding, and aggression) in rats and mice following presentation in the animals' drinking water for 7 days. The current series of experiments examined effects of acutely administered ddC and AZT on spontaneous locomotor activity and acoustic startle responses (with and without pre-pulse) in female Sprague-Dawley rats. Following intragastric administration, ddC reduced locomotion at all but the highest dose, whereas AZT had no significant effect on locomotor activity. Acutely administered ddC had no effect on ASR, whereas AZT increased ASR at the highest stimulus intensity. These data support the use of behavioral testing in the development of the antiviral nucleoside analogues, as behavioral testing may be more effective in identifying the neurologically active agents than is standard toxicity testing.
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Affiliation(s)
- D E Morse
- U.S. Food and Drug Administration, Division of Antiviral Drug Products, Rockville, MD 20857, USA
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Ferguson JL, Kandasamy SB, Harris AH, Davis HD, Landauer MR. Indomethacin attenuation of radiation-induced hyperthermia does not modify radiation-induced motor hypoactivity. J Radiat Res 1996; 37:209-215. [PMID: 8996979 DOI: 10.1269/jrr.37.209] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Exposure of rats to 5-10 Gy of ionizing radiation produces hyperthermia and reduces motor activity. Previous studies suggested that radiation-induced hyperthermia results from a relatively direct action on the brain and is mediated by prostaglandins. To test the hypothesis that hypoactivity may be, in part, a thermoregulatory response to this elevation in body temperature, adult male rats were given indomethacin (0.0, 0.5, 1.0, and 3.0 mg/kg, intraperitoneally), a blocker of prostaglandin synthesis, and were either irradiated (LINAC 18.6 MeV (nominal) high-energy electrons, 10 Gy at 10 Gy/min, 2.8 microseconds pulses at 2 Hz) or sham-irradiated. The locomotor activity of all rats was then measured for 30 min in a photocell monitor for distance traveled and number of vertical movements. Rectal temperatures of irradiated rats administered vehicle only were elevated by 0.9 +/- 0.2 degree C at the beginning and the end of the activity session. Although indomethacin, at the two higher doses tested, attenuated the hyperthermia in irradiated rats by 52-75%, it did not attenuate radiation-induced reductions in motor activity. These results indicate that motor hypoactivity after exposure to 10 Gy of high-energy electrons is not due to elevated body temperature or to the increased synthesis of prostaglandins.
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Affiliation(s)
- J L Ferguson
- Armed Forces Radiobiology Research Institute, Bethesda, MD 20889-5603, USA
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7
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Quak JJ, Schrijvers HG, Brakkee JG, Davis HD, Scheper RJ, Meijer CJ, Snow GB, Van Dongen GA. Expression and characterization of two differentiation antigens in human stratified squamous epithelia and carcinomas. Int J Cancer 1992; 50:507-13. [PMID: 1537614 DOI: 10.1002/ijc.2910500402] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [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: 12/27/2022]
Abstract
Using viable cells of a human squamous-cell carcinoma (SCC) cell line as immunogen, we generated 2 monoclonal antibodies, MAbs K984 and K928, to SCC surface antigens. Immunoperoxidase staining of frozen sections of normal epidermis revealed that MAb K984 reacts with the poorly differentiated basal cells, while MAb K928 is reactive with the more highly differentiated suprabasal cells. A similar complementary reaction pattern of these antibodies was demonstrated in the majority of well-differentiated human tumors and some moderately differentiated SCCs. In contrast, simultaneous reactivity of MAb K984 and K928 was found for the majority of cells within other well- and moderately differentiated SCCs, as well as all poorly differentiated SCCs. Further biochemical characterization indicated that the antigen recognized by MAb K984 is similar to the one recognized by MAb SF-25. MAb K928 recognizes a 50- to 55-kDa molecule under non-reducing conditions. Antibodies with similar features to MAb K928 have not been described previously. The antigens recognized by MAbs K984 and K928 can be regarded as novel markers associated with cellular maturation in squamous epithelia. The antigen detected by MAb K984 is probably associated with the proliferating fraction in SCCs.
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Affiliation(s)
- J J Quak
- Dept. of Otolaryngology/Head and Neck Surgery, Free University Hospital, Amsterdam, The Netherlands
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8
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Abstract
Effective radioprotection with minimal behavioral disruption is essential for the selection of protective agents to be used in manned spaceflight. This overview summarizes the studies on the behavioral toxicity of selected radioprotectors classified as phosphorothioates (WR-2721, WR-3689), bioactive lipids (16, 16 dimethylprostaglandin E2(DiPGE2), platelet activating factor (PAF), leukotriene C4), and immunomodulators (glucan, synthetic trehalose dicorynomycolate, and interleukin-1). Behavioral toxicity was examined in laboratory mice using a locomotor activity test. For all compounds tested, there was a dose-dependent decrease in locomotor behavior that paralleled the dose-dependent increase in radioprotection. While combinations of radioprotective compounds (DiPGE2 plus WR-2721) increased radioprotection, they also decreased locomotor activity. The central nervous system stimulant, caffeine, was able to mitigate the locomotor decrement produced by WR-3689 or PAF.
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Affiliation(s)
- M R Landauer
- Behavioral Sciences Department, Armed Forces Radiobiology Research Institute, Bethesda, MD 20889-5245, USA
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9
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Abstract
Leukotriene C4 (LTC4), a lipoxygenase metabolite of arachidonic acid, is a biological mediator of vasoregulation, pulmonary activity, shock, and inflammation, that has been demonstrated to have radioprotective efficacy. The effects of LTC4 on locomotor activity, rectal temperature and hematocrit were examined. Subcutaneous administration of doses of 1.0 micrograms LTC4/mouse or less did not affect locomotor activity. Doses of 5 or 10 micrograms LTC4/mouse, however, resulted in almost complete cessation of locomotion within 12-14 min following treatment. At these doses, activity was suppressed for 2 h with complete recovery by 3 h postinjection. While a dose as high as 10 micrograms LTC4 did not affect rectal temperature, 5 and 10 micrograms LTC4 resulted in hematocrit increases of 10% and 40% respectively. Hematocrit returned to baseline within 1 h after a 5 micrograms pretreatment of LTC4, and by 3 h following a 10 micrograms pretreatment. The duration of LTC4-induced locomotor suppression did not correlate with previously determined durations of LTC4-induced radioprotection.
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Affiliation(s)
- M R Landauer
- Department of Behavioural Sciences, Armed Forces Radiobiology Research Institute, Bethesda, MD 20814-5145
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Landauer MR, Davis HD, Dominitz JA, Weiss JF. Long-term effects of radioprotector WR-2721 on locomotor activity and body weight of mice following exposure to ionizing radiation. Toxicology 1988; 49:315-23. [PMID: 2836973 DOI: 10.1016/0300-483x(88)90014-5] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.6] [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: 01/02/2023]
Abstract
The effects of 13 Gy gamma-radiation alone and in combination with 200 mg/kg of the radioprotector S-2-(3-aminopropylamino)ethylphosphorothioic acid (WR-2721) on locomotor activity and body weight were examined in CD2F1 mice over a 10-month period. The results confirmed that WR-2721 is an excellent radioprotector against lethality. All mice receiving 13 Gy without WR-2721 died in 5-7 days. For mice that received WR-2721 alone or WR-2721 + radiation, survival at 30 days was 100% and 70%, respectively. Body weights of mice receiving WR-2721 without radiation were comparable to control animals. Body weights of animals given WR-2721 + radiation fell on days 1-5 and then increased until day 11, but remained below control values throughout the experiment. Animals in the radiation-only group did not exhibit any significant reductions in behavior until day 2 post-irradiation. Mice administered WR-2721 alone showed significantly reduced locomotor activity levels on day 0 then completely recovered within 24 h and exhibited normal body weights. Animals given WR-2721 before irradiation showed greater reductions in locomotor activity on day 0 than either the WR-2721 or radiation-only groups and recovered to control level by day 3. Beginning on day 5, they showed significant reductions in activity. Mice pretreated with WR-2721 that survived a normally lethal dose of radiation showed a 20-40% reduction in locomotor performance that recovered in 2-5 months.
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Affiliation(s)
- M R Landauer
- Department of Behavioral Sciences, Armed Forces Radiobiology Research Institute, Bethesda, MD 20814-5145
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Landauer MR, Davis HD, Dominitz JA, Weiss JF. Comparative behavioral toxicity of four sulfhydryl radioprotective compounds in mice: WR-2721, cysteamine, diethyldithiocarbamate, and N-acetylcysteine. Pharmacol Ther 1988; 39:97-100. [PMID: 2849137 DOI: 10.1016/0163-7258(88)90046-0] [Citation(s) in RCA: 32] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- M R Landauer
- Behavioral Sciences Department, Armed Forces Radiobiology Research Institute, Bethesda, MD 20814-5145
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13
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Landauer MR, Ledney GD, Davis HD. Locomotor behavior in mice following exposure to fission-neutron irradiation and trauma. Aviat Space Environ Med 1987; 58:1205-10. [PMID: 3426496] [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] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Locomotor activity, body weights, and food and water consumption were monitored in female mice for 35 d following a sublethal wound (W), burn (B), exposure to 3 Gray fission neutron radiation (R), or combination of these injuries: radiation-wound (RW) and radiation-burn (RB). Activity in groups W and RW was depressed immediately after injury, with recovery to control levels after 5 and 14 d, respectively. Mice that received radiation alone showed a biphasic response with decrements in activity on days 0-4 and 9-11. Groups B and RB exhibited depressed activity levels that differed significantly from control levels until day 17. Food intake was reduced for about 6 d in groups R, W, RW, and RB. Body weights decreased for 4 d in groups R, W, RW, and RB, but returned to control levels by the end of the experiment. Animals in group B did not show significant reduction in food intake or body weight. Water consumption was reduced for 5-6 d in groups R and RB and was increased in groups W, RW, and B. The data suggest that behavioral responses to fission-neutron radiation are exacerbated by tissue trauma.
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Affiliation(s)
- M R Landauer
- Department of Behavioral Sciences, Armed Forces Radiobiology Research Institute, Bethesda, Maryland 20814-5145
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14
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Abstract
The effects of the radioprotector S-2-(3-aminopropylamino)ethylphosphorothioic acid (WR-2721) on locomotor activity were evaluated in CD2F1 male mice. Separate groups of animals (N = 10/group) received an IP injection of vehicle, 25, 50, 100, 200, or 400 mg/kg of WR-2721 immediately before testing. Horizontal and vertical activity were measured using a Digiscan automated animal activity monitor. The latency to onset and duration of action of each dose of the radioprotector were recorded. For both behavioral measures, a significant reduction was observed in activity at doses of 200 and 400 mg/kg. A dose of 200 mg/kg had a 12- to 14-min latency to onset and significantly reduced behavioral activity for 3 hr. Mice injected with 400 mg/kg exhibited locomotor deficits within 8-10 min and were affected for up to 9 hr. The ED50 for horizontal and vertical activities at 1 hr postinjection were determined to be 271 and 105 mg/kg, respectively. The results demonstrate that significant reductions in locomotor activity are exhibited at doses of 200 mg/kg or more and that vertical activity was more sensitive to the disruptive effects of WR-2721 than was horizontal activity.
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Affiliation(s)
- M R Landauer
- Department of Behavioral Sciences, Armed Forces Radiobiology Research Institute, Bethesda, MD 20814-5145
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15
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Davis HD. Torquing in class: an interesting twist for orthodontists. Br J Orthod 1987; 14:199-202. [PMID: 3475126] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
A method of measuring the amount of slack inherent in the system of Edgewise brackets and archwires is presented, and some related problems concerning the use of turrets discussed.
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16
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Davis HD, Hendersen RW. Effects of conditioned fear on responsiveness to pain: long-term retention and reversibility by naloxone. Behav Neurosci 1985; 99:277-89. [PMID: 3843712] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The effect of a conditioned fear stimulus (CS) on responsiveness to pain was examined in three experiments. In Experiment 1, a CS that signaled shock attenuated freezing in response to shock, with the attenuation occurring several minutes after the shock. Naloxone blocked the effect of the CS. The effect of the CS, including its reversibility by naloxone, was retained over an interval of 90 days. Experiment 2 showed that this effect on freezing is due to associative fear conditioning, rather than blocking of conditioning to context by a novel cue. In Experiment 3, presenting a fear CS just prior to administering a tail-flick (radiant heat) test of nociception increased the tail-flick latencies; that is, the fear CS apparently induced hyperalgesia rather than analgesia. Because this result makes it difficult to interpret the change in freezing seen in the first experiment as reflecting antinociception, it raises questions about how pain might differentially affect different measures of pain responsiveness. A memory hypothesis is advanced to resolve the different effects obtained with the freezing and tail-flick tests.
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17
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Davis HD. Retraction of canines using bonded tube-brackets. Br J Orthod 1983; 10:187-97. [PMID: 6357274 DOI: 10.1179/bjo.10.4.187] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Investigations using a Force Analyser were carried out to test the characteristics of retractor springs fitted to a removable appliance and designed for insertion into a tube-bracket, bonded to the buccal surface of a canine. The retractors were shown to produce a counter-rotation couple when activated on the typodont. This type of canine retraction was then used clinically, and was found to produce less distal tilting than is noted with the single-point contact of a cantilever spring. Some spontaneous reduction in overjet was found to occur in each case of a small series. Possible mechanisms to account for this effect are discussed.
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18
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Abstract
The article describes the retraction and alignment of incisors by means of a labial arch activated by elastics and sliding through tubes on the molar cribs of a removable appliance. As necessary, extra-oral components may be incorporated.
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Abstract
Retraction of canines with control of tooth inclination is described, using the direct application of extra-oral traction. the technique requires a modified facebow to be inserted into buccal tubes on canine bands; no archwires or springs are involved. In the upper arch the facebow is connected to a standard variable pull headgear, while a supported cervical strap is required for the lower canines. Preliminary investigations are outlined and the procedure is illustrated by some clinical cases from a pilot feasibility study.
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Davis HD. A loopformer for archwires. Br J Orthod 1979; 6:3-4. [PMID: 295666 DOI: 10.1179/bjo.6.1.3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
A calibrated loop-forming jig is described, which can be used to bend standard sized loops and stops at known intervals along an archwire. A variety of loops may be constructed, using rectangular or round wire.
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Davis HD. Case for Diagnosis (? Mycosis Fungoides). Proc R Soc Med 1926; 19:10. [PMID: 19984875 PMCID: PMC1948806] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
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