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Mian MY, Sharmin D, Mondal P, Belayet JB, Hossain MM, McCusker P, Ryan KT, Fedorov AY, Green HA, Ericksen SS, Zamanian M, Tiruveedhula VVNPB, Cook JM, Chan JD. Development of non-sedating antischistosomal benzodiazepines. bioRxiv 2024:2024.01.26.577323. [PMID: 38352313 PMCID: PMC10862742 DOI: 10.1101/2024.01.26.577323] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/20/2024]
Abstract
The neglected tropical disease schistosomiasis infects over 200 million people worldwide and is treated with just one broad spectrum antiparasitic drug (praziquantel). Alternative drugs are needed in the event of emerging praziquantel resistance or treatment failure. One promising lead that has shown efficacy in animal models and a human clinical trial is the benzodiazepine meclonazepam, discovered by Roche in the 1970's. Meclonazepam was not brought to market because of dose-limiting sedative side effects. However, the human target of meclonazepam that causes sedation (GABAARs) are not orthologous to the parasite targets that cause worm death. Therefore, we were interested in whether the structure of meclonazepam could be modified to produce antiparasitic benzodiazepines that do not cause host sedation. We synthesized 18 meclonazepam derivatives with modifications at different positions on the benzodiazepine ring system and tested them for in vitro antiparasitic activity. This identified five compounds that progressed to in vivo screening in a murine model, two of which cured parasite infections with comparable potency to meclonazepam. When these two compounds were administered to mice that were run on the rotarod test, both were less sedating than meclonazepam. These findings demonstrate the proof of concept that meclonazepam analogs can be designed with an improved therapeutic index, and point to the C3 position of the benzodiazepine ring system as a logical site for further structure-activity exploration to further optimize this chemical series.
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Affiliation(s)
- Md Yeunus Mian
- Department of Chemistry and Biochemistry, Milwaukee Institute of Drug Discovery, University of Wisconsin-Milwaukee, Milwaukee, WI, USA
| | - Dishary Sharmin
- Department of Chemistry and Biochemistry, Milwaukee Institute of Drug Discovery, University of Wisconsin-Milwaukee, Milwaukee, WI, USA
| | - Prithu Mondal
- Department of Chemistry and Biochemistry, Milwaukee Institute of Drug Discovery, University of Wisconsin-Milwaukee, Milwaukee, WI, USA
| | - Jawad Bin Belayet
- Department of Chemistry and Biochemistry, Milwaukee Institute of Drug Discovery, University of Wisconsin-Milwaukee, Milwaukee, WI, USA
| | - M Mahmun Hossain
- Department of Chemistry and Biochemistry, Milwaukee Institute of Drug Discovery, University of Wisconsin-Milwaukee, Milwaukee, WI, USA
| | - Paul McCusker
- Department of Cell Biology, Neurobiology & Anatomy, Medical College of Wisconsin, Milwaukee, WI, United States of America
| | - Kaetlyn T. Ryan
- Department of Pathobiological Sciences, University of Wisconsin - Madison, Madison, WI, USA
| | - Alexander Y Fedorov
- UW Carbone Cancer Center, University of Wisconsin - Madison, Madison, WI, USA
| | - Heather A Green
- UW Carbone Cancer Center, University of Wisconsin - Madison, Madison, WI, USA
| | - Spencer S. Ericksen
- UW Carbone Cancer Center, University of Wisconsin - Madison, Madison, WI, USA
| | - Mostafa Zamanian
- Department of Pathobiological Sciences, University of Wisconsin - Madison, Madison, WI, USA
| | - V. V. N. Phani Babu Tiruveedhula
- Department of Chemistry and Biochemistry, Milwaukee Institute of Drug Discovery, University of Wisconsin-Milwaukee, Milwaukee, WI, USA
| | - James M. Cook
- Department of Chemistry and Biochemistry, Milwaukee Institute of Drug Discovery, University of Wisconsin-Milwaukee, Milwaukee, WI, USA
| | - John D. Chan
- Department of Cell Biology, Neurobiology & Anatomy, Medical College of Wisconsin, Milwaukee, WI, United States of America
- Department of Pathobiological Sciences, University of Wisconsin - Madison, Madison, WI, USA
- Department of Chemistry, University of Wisconsin - Oshkosh, Oshkosh, WI, USA
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Gunder LC, Johnson HR, Yao E, Moyer TH, Green HA, Sherer N, Zhang W, Carchman EH. Topical Protease Inhibitor Decreases Anal Carcinogenesis in a Transgenic Mouse Model of HPV Anal Disease. Viruses 2023; 15:v15041013. [PMID: 37112993 PMCID: PMC10146494 DOI: 10.3390/v15041013] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Revised: 04/17/2023] [Accepted: 04/18/2023] [Indexed: 04/29/2023] Open
Abstract
Anal cancer is a major health problem. This study seeks to determine if the topical protease inhibitor Saquinavir (SQV), is effective at the prevention of anal cancer in transgenic mice with established anal dysplasia. K14E6/E7 mice were entered into the study when the majority spontaneously developed high-grade anal dysplasia. To ensure carcinoma development, a subset of the mice was treated with a topical carcinogen: 7,12-Dimethylbenz[a]anthracene (DMBA). Treatment groups included: no treatment, DMBA only, and topical SQV with/without DMBA. After 20 weeks of treatment, anal tissue was harvested and evaluated histologically. SQV was quantified in the blood and anal tissue, and tissue samples underwent analysis for E6, E7, p53, and pRb. There was minimal systemic absorption of SQV in the sera despite high tissue concentrations. There were no differences in tumor-free survival between SQV-treated and respective control groups but there was a lower grade of histological disease in the mice treated with SQV compared to those untreated. Changes in E6 and E7 levels with SQV treatment suggest that SQV may function independently of E6 and E7. Topical SQV decreased histological disease progression in HPV transgenic mice with or without DMBA treatment without local side effects or significant systemic absorption.
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Affiliation(s)
- Laura C Gunder
- Department of Surgery, School of Medicine and Public Health, University of Wisconsin, 600 Highland Avenue, Madison, WI 53792, USA
| | - Hillary R Johnson
- Department of Surgery, School of Medicine and Public Health, University of Wisconsin, 600 Highland Avenue, Madison, WI 53792, USA
| | - Evan Yao
- Department of Surgery, School of Medicine and Public Health, University of Wisconsin, 600 Highland Avenue, Madison, WI 53792, USA
| | - Tyra H Moyer
- Department of Surgery, School of Medicine and Public Health, University of Wisconsin, 600 Highland Avenue, Madison, WI 53792, USA
| | - Heather A Green
- Carbone Cancer Center, School of Medicine and Public Health, University of Wisconsin, 600 Highland Avenue, Madison, WI 53705, USA
| | - Nathan Sherer
- McArdle Laboratory for Cancer Research and Institute for Molecular Virology, University of Wisconsin, 1111 Highland Avenue, Madison, WI 53706, USA
| | - Wei Zhang
- Department of Pathology and Laboratory Medicine, School of Medicine and Public Health, University of Wisconsin, 3170 UW Medical Foundation Centennial Building (MFCB), 1685 Highland Avenue, Madison, WI 53705, USA
- William S. Middleton Memorial Veterans Hospital, 2500 Overlook Terrace, Madison, WI 53705, USA
| | - Evie H Carchman
- Department of Surgery, School of Medicine and Public Health, University of Wisconsin, 600 Highland Avenue, Madison, WI 53792, USA
- Carbone Cancer Center, School of Medicine and Public Health, University of Wisconsin, 600 Highland Avenue, Madison, WI 53705, USA
- William S. Middleton Memorial Veterans Hospital, 2500 Overlook Terrace, Madison, WI 53705, USA
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Gunder LC, Johnson HR, Green HA, Bilger A, Moyer TH, Zhang W, Ziolkowski MR, Bertrang PA, Carchman EH. The use of a topical protease inhibitor, Saquinavir, to alleviate mouse papillomavirus-mediated anal disease. Virology 2022; 576:96-104. [PMID: 36206607 DOI: 10.1016/j.virol.2022.09.012] [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: 08/18/2022] [Revised: 09/26/2022] [Accepted: 09/26/2022] [Indexed: 02/06/2023]
Abstract
Select protease inhibitors (PI) have been found to be effective in decreasing human papillomavirus oncoprotein expression. This study evaluated whether the topical PI, Saquinavir (SQV), promotes viral clearance in an infectious mouse model with Mus musculus papillomavirus 1 (MmuPV1). NOD scid gamma (NSG) mice were anally infected with ∼4 × 108 viral genome equivalents of MmuPV1 and 120 days post-infection (when majority have high-grade anal dysplasia), began topical treatments: control (mock), 7,12-dimethylbenz(a)anthracene (DMBA) only, once weekly to promote carcinogenesis, 1% SQV only, daily (Monday - Friday), and SQV + DMBA. Viral MmuPV1 load was analyzed from anal lavages pre and post-treatment. Anal tissue was harvested, processed, and evaluated for drug absorption, grade of anal disease, and anal viral RNA. Results suggest that topical SQV promotes decreased viral shedding in female mice treated with SQV.
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Affiliation(s)
- Laura C Gunder
- Department of Surgery, School of Medicine and Public Health, University of Wisconsin-Madison, 600 Highland Ave, Madison, WI, 53792, USA.
| | - Hillary R Johnson
- Department of Surgery, School of Medicine and Public Health, University of Wisconsin-Madison, 600 Highland Ave, Madison, WI, 53792, USA.
| | - Heather A Green
- University of Wisconsin Carbone Cancer Center, School of Medicine and Public Health, University of Wisconsin-Madison, 600 Highland Ave, Madison, WI, 53705, USA.
| | - Andrea Bilger
- McArdle Laboratory for Cancer Research, Department of Oncology, School of Medicine and Public Health, University of Wisconsin-Madison, Wisconsin Institutes for Medical Research, 1111 Highland Ave, Madison, WI, 53705, USA.
| | - Tyra H Moyer
- Department of Surgery, School of Medicine and Public Health, University of Wisconsin-Madison, 600 Highland Ave, Madison, WI, 53792, USA.
| | - Wei Zhang
- Department of Pathology and Laboratory Medicine, School of Medicine and Public Health, University of Wisconsin-Madison, 3170 UW Medical Foundation Centennial Building (MFCB),1685 Highland Avenue, Madison, WI, 53705, USA.
| | - Marissa R Ziolkowski
- Department of Surgery, School of Medicine and Public Health, University of Wisconsin-Madison, 600 Highland Ave, Madison, WI, 53792, USA.
| | - Payton A Bertrang
- Department of Surgery, School of Medicine and Public Health, University of Wisconsin-Madison, 600 Highland Ave, Madison, WI, 53792, USA.
| | - Evie H Carchman
- Department of Surgery, School of Medicine and Public Health, University of Wisconsin-Madison, 600 Highland Ave, Madison, WI, 53792, USA; University of Wisconsin Carbone Cancer Center, School of Medicine and Public Health, University of Wisconsin-Madison, 600 Highland Ave, Madison, WI, 53705, USA; William S. Middleton Memorial Veterans Hospital, 2500 Overlook Terrace, Madison, WI, 53705, USA.
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Sullivan ML, Green HA, Verdonk JC. Engineering Alfalfa to Produce 2- O-Caffeoyl-L-Malate (Phaselic Acid) for Preventing Post-harvest Protein Loss via Oxidation by Polyphenol Oxidase. Front Plant Sci 2021; 11:610399. [PMID: 33519867 PMCID: PMC7838361 DOI: 10.3389/fpls.2020.610399] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2020] [Accepted: 12/09/2020] [Indexed: 05/28/2023]
Abstract
Many plants accumulate high levels of hydroxycinnamoyl esters and amides in their tissues, presumably to protect against biotic and abiotic stress. Red clover (Trifolium pretense) leaves accumulate high levels [5-15 mmol/kg fresh weight (FW)] of caffeic acid derivatives, including phaselic acid (2-O-caffeoyl-L-malate). Oxidation of caffeoyl-malate by an endogenous polyphenol oxidase (PPO) has been shown to help preserve forage protein after harvest and during storage as silage, which should improve N use efficiency in dairy and other ruminant production systems. The widely grown forage alfalfa lacks both PPO and PPO substrates and experiences substantial loss of protein following harvest. We previously identified a hydroxycinnamoyl-coenzyme A (CoA):malate hydroxycinnamoyl transferase (HMT, previously called HCT2) responsible for phaselic accumulation in red clover. With the goal of producing PPO-oxidizable compounds in alfalfa to help preserve forage protein, we expressed red clover HMT in alfalfa. Leaves of these alfalfa accumulated mainly p-coumaroyl- and feruloyl-malate (up to 1.26 and 0.25 mmol/kg FW, respectively). Leaves of HMT-expressing alfalfa supertransformed with an RNA interference (RNAi) construct to silence endogenous caffeoyl-CoA acid O-methyltransferase (CCOMT) accumulated high levels of caffeoyl-malate, as well as the p-coumaroyl and feruloyl esters (up to 2.16, 2.08, and 3.13 mmol/kg FW, respectively). Even higher levels of caffeoyl- and p-coumaroyl-malate were seen in stems (up to 8.37 and 3.15 mmol/kg FW, respectively). This level of caffeoyl-malate accumulation was sufficient to inhibit proteolysis in a PPO-dependent manner in in vitro experiments, indicating that the PPO system of post-harvest protein protection can be successfully adapted to alfalfa.
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Affiliation(s)
- Michael L. Sullivan
- US Dairy Forage Research Center, Agricultural Research Service, USDA, Madison, WI, United States
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Guadagno JV, Warburton EA, Jones PS, Day DJ, Aigbirhio FI, Fryer TD, Harding S, Price CJ, Green HA, Barret O, Gillard JH, Baron JC. How affected is oxygen metabolism in DWI lesions?: A combined acute stroke PET-MR study. Neurology 2006; 67:824-9. [PMID: 16966545 DOI: 10.1212/01.wnl.0000233984.66907.db] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.1] [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] [Indexed: 02/07/2023] Open
Abstract
OBJECTIVE To use back-to-back diffusion-weighted imaging (DWI) and PET to obtain quantitative measures of the cerebral metabolic rate of oxygen (CMRO(2)) within DWI lesions, and to assess the perfusion-metabolism coupling status by measuring the cerebral blood flow and the oxygen extraction fraction within DWI lesions. METHODS Six prospectively recruited acute carotid-territory stroke patients completed the imaging protocol, which was commenced 7 to 21 hours from onset and combined DWI derived from state-of-the-art diffusion tensor imaging sequencing using a 3-T magnet and fully quantitative (15)O-PET. The PET variables were obtained in individual DWI lesions in each patient. RESULTS Across patients, the CMRO(2) was reduced in the DWI lesion relative to mirror (mean reduction 39.5%; p = 0.028). Examining individual DWI lesions, however, revealed considerable variability in the extent of this CMRO(2) reduction. The flow-metabolism coupling pattern underlying the DWI lesion was also variable, including ongoing ischemia, mild oligemia, and partial or complete reperfusion. DISCUSSION Diffusion-weighted imaging (DWI) lesions generally reflect substantial disruption of energy metabolism. However, the degree of metabolic disruption is variable, indicating DWI lesions may not always represent irreversibly damaged tissue. Finally, because DWI lesions can persist despite reperfusion, assessment of perfusion is necessary for interpretation of DWI changes in acute stroke.
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Affiliation(s)
- J V Guadagno
- Department of Clinical Neurosciences, University of Cambridge, UK
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Abstract
We have identified a second RpoH homolog, RpoH(II), in the alpha-proteobacterium Rhodobacter sphaeroides. Primary amino acid sequence comparisons demonstrate that R. sphaeroides RpoH(II) belongs to a phylogenetically distinct group with RpoH orthologs from alpha-proteobacteria that contain two rpoH genes. Like its previously identified paralog, RpoH(I), RpoH(II) is able to complement the temperature-sensitive phenotype of an Escherichia coli sigma(32) (rpoH) mutant. In addition, we show that recombinant RpoH(I) and RpoH(II) each transcribe two E. coli sigma(32)-dependent promoters (rpoD P(HS) and dnaK P1) when reconstituted with E. coli core RNA polymerase. We observed differences, however, in the ability of each sigma factor to recognize six R. sphaeroides promoters (cycA P1, groESL(1), rpoD P(HS), dnaK P1, hslO, and ecfE), all of which resemble the E. coli sigma(32) promoter consensus. While RpoH(I) reconstituted with R. sphaeroides core RNA polymerase transcribed all six promoters, RpoH(II) produced detectable transcripts from only four promoters (cycA P1, groESL(1), hslO, and ecfE). These results, in combination with previous work demonstrating that an RpoH(I) mutant mounts a typical heat shock response, suggest that while RpoH(I) and RpoH(II) have redundant roles in response to heat, they may also have roles in response to other environmental stresses.
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Affiliation(s)
- Heather A Green
- Department of Bacteriology, University of Wisconsin-Madison, Madison, WI 53706, USA
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Abstract
This article summarized methods to obtain RNA polymerase and sigma factors that can be used to analyze the in vitro control of gene expression by the facultative phototroph R. sphaeroides. While not a topic of this article, these purified components also allow one to analyze R. sphaeroides promoters that use activators to stimulate transcription. We expect that these approaches will be increasingly useful as investigators continue to dissect the number of unusual signal transduction pathways that control gene expression in this and other related species.
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Affiliation(s)
- Jennifer R Anthony
- Department of Bacteriology, University of Wisconsin-Madison, 1550 Linden Drive, Madison, Wisconsin 53706, USA
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Abstract
We investigated the fine genetic structure of colonies of the ant, Leptothorax acervorum, to examine how queens share parentage (skew) in a social insect with multiple queens (polygyny). Overall, 494 individuals from eight polygynous field colonies were typed at up to seven microsatellite loci each. The first main finding was that surprisingly many sexual progeny (60% of young queens and 49% of young males) were not the offspring of the extant queens within their colonies. This implies that a high turnover (brief reproductive lifespan) of queens within colonies could be an important feature of polygyny. The second main result was that in most colonies relatedness among sexual progeny fell significantly below that expected among full siblings, proving that these progeny were produced by more than one singly-mated queen, but that skew in two colonies where the data permitted its calculation was moderate to high. However, relative to a German population, the study population is characterized by low queen-queen relatedness and low skew in female production, which is in line with the predictions of skew theory.
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Affiliation(s)
- A F Bourke
- Institute of Zoology, Zoological Society of London, UK
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Green HA, Burd EE, Nishioka NS, Compton CC. Skin graft take and healing following 193-nm excimer, continuous-wave carbon dioxide (CO2), pulsed CO2, or pulsed holmium: YAG laser ablation of the graft bed. Arch Dermatol 1993; 129:979-88. [PMID: 8352622] [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] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
BACKGROUND Ablative lasers have been used for cutaneous surgery for greater than two decades since they can remove skin and skin lesions bloodlessly and efficiently. Because full-thickness skin wounds created after thermal laser ablation may require skin grafting in order to heal, we have examined the effect of the residual laser-induced thermal damage in the wound bed on subsequent skin graft take and healing. In a pig model, four different pulsed and continuous-wave lasers with varying wavelengths and radiant energy exposures were used to create uniform fascial graft bed thermal damage of approximately 25, 160, 470, and 1100 microns. Meshed split-thickness skin graft take and healing on the thermally damaged fascial graft beds were examined on a gross and microscopic level on days 3 and 7, and then weekly up to 42 days. RESULTS Laser-induced thermal damage on the graft bed measuring greater than 160 +/- 60 microns in depth significantly decreased skin graft take. Other deleterious effects included delayed graft revascularization, increased inflammatory cell infiltrate at the graft-wound bed interface, and accelerated formation of hypertrophied fibrous tissue within the graft bed and underlying muscle. CONCLUSIONS Ablative lasers developed for cutaneous surgery should create less than 160 +/- 60 microns of residual thermal damage to permit optimal skin graft take and healing. Pulsed carbon dioxide and 193-nm excimer lasers may be valuable instruments for the removal of full-thickness skin, skin lesions, and necrotic tissue, since they create wound beds with minimal thermal damage permitting graft take comparable to that achieved with standard surgical techniques.
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Affiliation(s)
- H A Green
- Department of Dermatology, Boston (Mass) University School of Medicine
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Green HA, Drake L. Aging, sun damage, and sunscreens. Clin Plast Surg 1993; 20:1-8. [PMID: 8420699] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Intrinsic aging deleteriously changes the structure and function of human skin. Acute and chronic sun exposure may accelerate the aging processes in skin. Patients should avoid sun during the peak hours of sunshine, wear protective clothing, and use sunscreens while outdoors. Acceptable medical and surgical treatments may be offered to patients who manifest the cutaneous consequences of aging and sun exposure.
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Affiliation(s)
- H A Green
- Department of Dermatology, Boston University School of Medicine, Massachusetts
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Green HA, Burd E, Nishioka NS, Brüggemann U, Compton CC. Middermal wound healing. A comparison between dermatomal excision and pulsed carbon dioxide laser ablation. Arch Dermatol 1992; 128:639-45. [PMID: 1575527 DOI: 10.1001/archderm.128.5.639] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
BACKGROUND Continuous-wave carbon dioxide lasers are not widely used for the surgical removal of most skin lesions because it is difficult to control laser ablation and the extensive laser-induced thermal damage slows healing. Pulsed lasers provide means to reduce thermal damage produced during laser ablation and permit precise control of tissue removed during ablation. Using a swine model, we compared on a gross and microscopic level the healing of middermal wounds of similar depth and area created by a dermatome and a focused pulsed CO2 laser. RESULTS Pulsed CO2 laser ablation removed skin precisely and bloodlessly with 85 +/- 15 microns (mean +/- SD) of residual thermal damage covering the surface of the wound. Compared with the dermatome, tissue reepithelialization was delayed in the laser wounds at day 3. By day 7, epithelial coverage of the laser-created wounds was not significantly different from the dermatome-created wounds. No significant difference in the appearance of the two wounds was noted at 42 days. CONCLUSIONS We conclude that the focused pulsed CO2 laser is capable of precisely and bloodlessly ablating skin with conservation of residual subjacent adnexal elements, minimal early interference with epibolic epithelial outgrowth, and no pathologic effects on the wound healing process. Pulsed CO2 lasers may be a valuable instrument for the conservative ablation of skin and skin lesions.
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Affiliation(s)
- H A Green
- Department of Dermatology, Harvard Medical School, Boston, Mass. 02114
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Green HA, Moschella S. Multiple invasive squamous cell carcinomas and common variable immunodeficiency. Arch Dermatol 1992; 128:412-3. [PMID: 1550383] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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Green HA, Bua D, Anderson RR, Nishioka NS. Burn depth estimation using indocyanine green fluorescence. Arch Dermatol 1992; 128:43-9. [PMID: 1739286] [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: 12/28/2022]
Abstract
Expedient primary excision of deep dermal and full-thickness burn wounds with subsequent skin grafting is the standard of care in most burn institutions, but differentiating full-thickness from partial-thickness burns is often difficult. Because accurate early assessment of burn depth may improve care, a variety of technical methods have attempted to measure burn depth but these methods have had limited success. We describe a new technique to determine burn depth that uses infrared (840- to 850-nm) fluorescence emission from intravenously administered indocyanine green following excitation with infrared (780 nm) and UV light (369 nm). Full-thickness and partial-thickness burns in hairless rat skin were distinguished based on the infrared-induced and UV-induced fluorescence intensity ratios relative to normal, unburned skin immediately after the burn and on post-burn days 1 through 3 and 7. Dual-wavelength excitation of indocyanine green infrared fluorescence can delineate full-thickness from partial-thickness burns at an early date, allowing prognosis, surgical planning, and early primary excision and grafting.
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Affiliation(s)
- H A Green
- Harvard Medical School, Department of Dermatology, Massachusetts General Hospital, Boston 02114
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Kochevar IE, Walsh AA, Green HA, Sherwood M, Shih AG, Sutherland BM. DNA damage induced by 193-nm radiation in mammalian cells. Cancer Res 1991; 51:288-93. [PMID: 1988091] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The contribution of DNA damage to the effects of 193-nm excimer laser radiation on mammalian cells in culture was studied in order to evaluate the mutagenic potential of this UV wavelength in vivo. Two approaches were taken: measurement of pyrimidine dimer-specific endonuclease-sensitive sites/megabase and comparison of the 193-nm radiation-induced cytotoxicity in normal versus DNA repair-deficient cells. The formation of pyrimidine dimer-specific endonuclease-sensitive sites/megabase was inversely related to the thickness of the cytoplasm overlying the nuclei of normal human fibroblasts (NHF) and Chinese hamster ovary cells. The results of these measurements and a calculation of the absorption coefficient of cytoplasm indicate that each 1 micron of cytoplasm attenuates the incident radiation by greater than 90% and, therefore, the nuclear DNA in tissue will be highly protected from 193-nm radiation by overlying cytoplasm. The reduction in colony-forming ability induced by 254-nm, 193-nm, and X-ray radiation was measured in NHF, xeroderma pigmentosum (group A) cells, and ataxia telangiectasia cells. Xeroderma pigmentosum (group A) cells were 16.5 times more sensitive to 254-nm radiation but only 3.5 times more sensitive to 193-nm radiation than NHF cells, indicating that cyclobutylpyrimidine dimers were not the major lethal lesion formed at 193 nm. AT cells were 3.4 times more sensitive to X-rays than NHF cells, but these cell types were almost equally sensitive to 193-nm radiation, indicating that 193 nm did not induce the same type of lethal lesions as X-rays.
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Affiliation(s)
- I E Kochevar
- Wellman Laboratories of Photomedicine, Department of Dermatology, Massachusetts General Hospital, Harvard Medical School, Boston 02114
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Abstract
Pulsed lasers produce efficient and precise tissue ablation with limited residual thermal damage. In this study, the efficiency of pulsed CO2 laser ablation of burned and normal swine skin was studied in vitro with a mass loss technique. The heats of ablation for normal and burned skin were 2,706 and 2,416 J/cm3 of tissue ablated, respectively. The mean threshold radiant exposures for ablating normal skin and eschar were 2.6 J/cm2 and 3.0 J/cm2, respectively. Radiant exposures greater than 19 J/cm2 produced a plasma, which decreased the efficiency of laser ablation. Thus the radiant exposures for efficient ablation range from 4 to 19 J/cm2, and within this radiant exposure range 20-40 microns of tissue are ablated per pulse. We also examined, on a gross and histopathologic basis, in vivo burn eschar excision with a pulsed CO2 laser. The laser allowed bloodless excisions of full thickness burns on the backs of male hairless rats. The zone of thermal damage was approximately 85 microns over the subjacent fascia. The pulsed CO2 laser can ablate burn eschar efficiently, precisely, and bloodlessly and may prove valuable for the excision of burned and necrotic tissue.
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Affiliation(s)
- H A Green
- Department of Dermatology, Massachusetts General Hospital, Boston 02114
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Green HA, Margolis R, Boll J, Kochevar IE, Parrish JA, Oseroff AR. Unscheduled DNA synthesis in human skin after in vitro ultraviolet-excimer laser ablation. J Invest Dermatol 1987; 89:201-4. [PMID: 3598211 DOI: 10.1111/1523-1747.ep12470562] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
DNA damage repaired by the excision repair system and measured as unscheduled DNA synthesis (UDS) was assessed in freshly excised human skin after 193 and 248 nm ultraviolet (UV)-excimer laser ablative incisions. Laser irradiation at 248 nm induced DNA damage throughout a zone of cells surrounding the ablated and heat-damaged area. In contrast, with 193 nm irradiation UDS was not detected in cells adjacent to the ablated area, even though DNA strongly absorbs this wavelength. Our results suggest that the lack of UDS after 193 nm irradiation is due to: "shielding" of DNA by the cellular interstitium, membrane, and cytoplasm, DNA damage that is not repaired by excision repair, or thermal effects that either temporarily or permanently inhibit the excision repair processes.
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Shields CL, Shields JA, Eagle RC, Peyster RG, Conner BE, Green HA. Orbital metastasis from a carcinoid tumor. Computed tomography, magnetic resonance imaging, and electron microscopic findings. Arch Ophthalmol 1987; 105:968-71. [PMID: 3606458 DOI: 10.1001/archopht.1987.01060070104038] [Citation(s) in RCA: 33] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
An otherwise asymptomatic 63-year-old woman with a history of a carcinoid tumor of the ileum and a cutaneous melanoma of the shoulder developed unilateral proptosis. Orbital ultrasonography, computed tomography, and magnetic resonance imaging revealed a large, well-circumscribed orbital mass involving the superior rectus muscle. The surgically excised tumor was studied by light microscopy, histochemistry, and transmission electron microscopy. These studies confirmed the diagnosis of carcinoid tumor. The clinical and pathologic features of this rare type of orbital metastasis are discussed.
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Abstract
A selected strain of rat hepatoma cells was evaluated for its utility in the assay of mutation. We demonstrate that these cells have practical and theoretical advantages over most other mammalian cells utilized for the mutation assay at the HGPRT locus. Characteristics of the H4IIE cell line which enhance the ability of the HGPRT assay to detect mutation include: intrinsic metabolic capabilities; small cell size, and lack of mobility; colony-forming efficiency of 85-95%; a background mutation level between 0.9 and 3 mutants per 10(5) viable cells; and the ability to proliferate in medium containing 5% fetal bovine serum and 5% horse serum. The optimal expression period for the maximum frequency of mutants was investigated using UVC as the mutagenic agent, and found to plateau after 8-10 days. The metabolic capacity of this cell line was demonstrated using 2-aminoanthracene and cyclophosphamide, two types of mutagens requiring biotransformation for activity. We conclude that the use of the H4/HGPRT system could prove valuable in the mutagenic screening of suspect environmental agents.
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