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1.
Pediatr Radiol ; 52(6): 1038-1047, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35394163

RESUMO

BACKGROUND: Many studies on pediatric inflammatory multisystem syndrome temporally associated with severe acute respiratory syndrome coronavirus 2 (PIMS-TS) have described abdominal findings as part of multisystem involvement, with limited descriptions of abdominal imaging findings specific to PIMS-TS. OBJECTIVE: To perform a detailed evaluation of abdominal imaging findings in children with PIMS-TS. MATERIALS AND METHODS: We performed a single-center retrospective study of children admitted to our institution between April 2020 and January 2021 who fulfilled Royal College of Paediatrics and Child Health criteria for PIMS-TS and who had cross-sectional abdominal imaging. We studied clinical data, abdominal imaging, laboratory markers, echocardiography findings, treatment and outcomes for these children. We also reviewed the literature on similar studies. RESULTS: During the study period, 60 PIMS-TS cases were admitted, of whom 23 required abdominal imaging. Most (74%) were from a Black, Asian or minority ethnic background and they had an average age of 7 years (range 2-14 years). All children had fever and gastrointestinal symptoms on presentation with elevated C-reactive protein, D-dimer and fibrinogen. Most had lymphopenia, raised ferritin and hypoalbuminemia, with positive severe acute respiratory syndrome coronavirus 2 immunoglobulin G antibodies in 65%. Free fluid (78%), right iliac fossa mesenteric inflammation (52%), and significantly enlarged mesenteric lymph nodes (52%) were the most common imaging findings. Appendiceal inflammation (30%) and abnormal distal ileum and cecum/ascending colon wall thickening (35%) were also common. All children responded well to medical management alone, with no mortality. CONCLUSION: In addition to free fluid, prominent lymphadenopathy, and inflammatory changes in the right iliac fossa, we found abnormal long-segment ileal thickening and appendicitis to be frequent findings. Recognition of appendiceal involvement as a component of the PIMS-TS spectrum should help clinicians avoid unnecessary surgical intervention as part of a multidisciplinary team approach.


Assuntos
COVID-19 , SARS-CoV-2 , Adolescente , COVID-19/complicações , Criança , Pré-Escolar , Estudos Transversais , Humanos , Estudos Retrospectivos , Síndrome de Resposta Inflamatória Sistêmica/diagnóstico por imagem
2.
Ecol Modell ; 465: 1-109635, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34675451

RESUMO

The Chesapeake Bay is the largest, most productive, and most biologically diverse estuary in the continental United States providing crucial habitat and natural resources for culturally and economically important species. Pressures from human population growth and associated development and agricultural intensification have led to excessive nutrient and sediment inputs entering the Bay, negatively affecting the health of the Bay ecosystem and the economic services it provides. The Chesapeake Bay Program (CBP) is a unique program formally created in 1983 as a multi-stakeholder partnership to guide and foster restoration of the Chesapeake Bay and its watershed. Since its inception, the CBP Partnership has been developing, updating, and applying a complex linked modeling system of watershed, airshed, and estuary models as a planning tool to inform strategic management decisions and Bay restoration efforts. This paper provides a description of the 2017 CBP Modeling System and the higher trophic level models developed by the NOAA Chesapeake Bay Office, along with specific recommendations that emerged from a 2018 workshop designed to inform future model development. Recommendations highlight the need for simulation of watershed inputs, conditions, processes, and practices at higher resolution to provide improved information to guide local nutrient and sediment management plans. More explicit and extensive modeling of connectivity between watershed landforms and estuary sub-areas, estuarine hydrodynamics, watershed and estuarine water quality, the estuarine-watershed socioecological system, and living resources will be important to broaden and improve characterization of responses to targeted nutrient and sediment load reductions. Finally, the value and importance of maintaining effective collaborations among jurisdictional managers, scientists, modelers, support staff, and stakeholder communities is emphasized. An open collaborative and transparent process has been a key element of successes to date and is vitally important as the CBP Partnership moves forward with modeling system improvements that help stakeholders evolve new knowledge, improve management strategies, and better communicate outcomes.

3.
J Appalach Health ; 5(1): 1-5, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38023115

RESUMO

For the past five years, the Journal of Appalachian Health has published timely, high-quality research from within Appalachia. We also welcome submissions from those working outside of Appalachia who produce quality research of direct relevance to our region.

4.
Br J Radiol ; 96(1147): 20220274, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37162001

RESUMO

OBJECTIVE: Morphological features of an enlarged endolymphatic duct (ED) and sac (ES) are imaging biomarkers for genotype and hearing loss phenotype. We determine which biomarkers can be measured in a reproducible manner, facilitating further clinical prediction studies in enlarged vestibular aqueduct hearing loss. METHODS: A rater reproducibility study. Three consultant radiologists independently measured previously reported MRI ED & ES biomarkers (ED midpoint width, maximal ED diameter closest to the vestibule, ES length, ES width and presence of ES signal heterogeneity) and presence of incomplete partition Type 2 from 80 ears (T2 weighted axial MRI). Interclass correlation coefficients (ICC) and Gwet's Agreement Coefficients (AC) were generated to give a measure of reproducibility for both continuous and categorical feature measures respectively. RESULTS: ES length, width and sac signal heterogeneity showed adequate reproducibility (ICC 95% confidence intervals 0.77-0.95, Gwet's AC for sac heterogeneity 0.64). When determining ED midpoint width, measurements from multiple raters are required for "good" reliability (ICC 95% CI 0.75-0.89). Agreement on the presence of incomplete partition Type 2 ranged from "moderate" to "substantial". CONCLUSIONS: Regarding MR imaging, the opinion of multiple expert raters should be sought when determining the presence of an enlarged ED defined by midpoint width. ED midpoint, ES length, width and signal heterogeneity have adequate reproducibility to be further explored as clinical predictors for audiological phenotype. ADVANCES IN KNOWLEDGE: We report which ED & ES biomarkers are reproducibly measured. Researchers can confidently utilise these specific biomarkers when modelling progressive hearing loss associated with enlarged vestibular aqueduct.


Assuntos
Perda Auditiva Neurossensorial , Perda Auditiva , Humanos , Reprodutibilidade dos Testes , Estudos Retrospectivos , Tomografia Computadorizada por Raios X , Perda Auditiva Neurossensorial/diagnóstico por imagem , Perda Auditiva/diagnóstico por imagem , Imageamento por Ressonância Magnética , Hipertrofia , Biomarcadores
5.
J Nat Prod ; 75(3): 385-93, 2012 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-22324723

RESUMO

Toward the objective of designing a structurally modified analogue of the combretastatin A-4 phosphate prodrug (1b) with the potential for increased specificity toward thyroid carcinoma, synthesis of a series of iodocombstatin phosphate (11a-h) and diiodocombstatin phosphate prodrugs (12a-h) has been accomplished. The diiodo series was obtained via 8a and 9c from condensation of 4 and 6, and the iodo sequence involved a parallel pathway. Both series of iodocombstatins were found to display significant to powerful inhibition of the growth of a panel of human cancer cell lines and of the murine P388 lymphocytic leukemia cell line. Of the diiodo series, 12a was also found to markedly inhibit growth of pediatric neuroblastoma, and monoiodocombstatin 9a strongly inhibited HUVEC growth. Overall, the strongest activity was found against the breast, CNS, leukemia, lung, and prostate cancer cell lines and the least activity against the pancreas and colon lines. Parallel biological investigations of tubulin interaction, antiangiogenesis, and antimicrobial effects were also conducted.


Assuntos
Antineoplásicos/síntese química , Hidrocarbonetos Iodados/síntese química , Hidrocarbonetos Iodados/farmacologia , Compostos Organofosforados/síntese química , Pró-Fármacos/síntese química , Estilbenos/síntese química , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Criança , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Humanos , Hidrocarbonetos Iodados/química , Masculino , Camundongos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Compostos Organofosforados/química , Compostos Organofosforados/farmacologia , Pró-Fármacos/química , Pró-Fármacos/farmacologia , Estilbenos/química , Estilbenos/farmacologia
6.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 7): o2250-1, 2012 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-22798903

RESUMO

The title compound, C(26)H(40)N(5)O(13)P·CH(3)OH·H(2)O, crystallizes with one water and one methanol mol-ecule providing important crystal-binding inter-actions. The compound has the unusual feature of having two but-oxy-carbonyl groups bound to one N atom. The conventional attractive hydrogen bonds involving hy-droxy, amine and water donors include bifurcations at both donors and acceptors with novel R(1) (2)(6) and R(2) (1)(6) motifs. These are supplemented by C-H⋯O inter-actions between adjacent mol-ecules forming chain and R(2) (2)(10) ring motifs.

7.
J Appalach Health ; 4(2): 4-7, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-38028328

RESUMO

With the passing of our founding Editor-in-Chief, Dr. F. Douglas Scutchfield, the Journal of Appalachian Health team reflects on a life well lived and a monumental public legacy left behind. We thank "Scutch" for enriching the lives of so many, and we commit to growing the Journal in his honor.

8.
J Trauma Acute Care Surg ; 93(3): 340-346, 2022 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-35653510

RESUMO

INTRODUCTION: The Eastern Association for the Surgery of Trauma mission includes fostering research and providing career development opportunities. Eastern Association for the Surgery of Trauma has awarded for 20 years a research scholarship to a promising young investigator. The research mentorship efforts were expanded 5 years ago with the INVEST-C Hack-a-thon. INVEST-C provides an intensive, short-term engagement to propel junior faculty toward establishing research independence. This study investigates the impact of these programs on academic productivity. METHODS: Pubmed records, National Institutes of Health (NIH) Reporter data, and SCOPUS h-index were acquired for all scholarship (SCH) awardees from 2002 to 2021 (n = 20) and all INVEST-C (INV) participants (2017-2020, n = 19). Current type of practice, total number of funding awards, and timing of first award were ascertained. INVEST-C participants were also surveyed on an annual basis to track their progress. Medians (interquartile range [IQR]) are reported and compared (analysis of variance). RESULTS: Median publications (PUBs) of SCH awardees were 56 (IQR, 33-88), h-index was 16 (IQR, 12-21), and 25% of awardees have ≥1 NIH grant since their SCH. Among the last 10 awardees with a minimum of 2 years from SCH, 40% have received an NIH award compared with a mean NIH funding rate of 18.5% over the same period. For those remaining in academics (90% SCH), PUBs were higher for those >5 years (66 [IQR, 51-115]) versus <5 years from their SCH (33 [22-59]; p = 0.05), but there was no difference in h-index (16 [IQR, 14-25] vs. 15 [9-19], p = NS). Comparing the most recent 5 years of SCH to INV group, there was no difference in academic productivity as measured by total PUBs (SCH, 33 [IQR, 22-59] vs. INV, 34 [IQR, 18-44]; p = 0.7) or h-index (INV, 9 [IQR, 5-14]; p = 0.1). However, no attendee held research funding before INV, but 31.6% (6 of 19 attendees) have subsequently acquired ≥1 funding award (11 non-NIH, 1 NIH) in the short interval since participation. CONCLUSION: Investments in research activities have translated to significant extramural funding. Those in the last 5 years have been particularly fruitful with INV participants already achieving equal median academic productivity to SCH recipients. LEVEL OF EVIDENCE: Prognostic and Epidemiologic; Level III.


Assuntos
Distinções e Prêmios , Pesquisa Biomédica , Cirurgiões , Organização do Financiamento , Humanos , National Institutes of Health (U.S.) , Pesquisadores , Estados Unidos
9.
Arch Dis Child ; 107(6): 575-581, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35177407

RESUMO

Rate and severity of radiological features of physical abuse in children during the first UK-wide COVID-19 enforced national lockdown. OBJECTIVE: To assess the number, type and outcome of radiological investigations for children presenting to hospital with suspected physical abuse (SPA; including abusive head trauma) during the first national COVID-19 enforced lockdown compared with the prelockdown period. DESIGN: Multicentre, retrospective, observational, interrupted time series analysis. SETTING: Eight secondary/tertiary paediatric centres between January 2018 and July 2020 inclusive. PARTICIPANTS: 1587 hospital assessed children undergoing radiographic skeletal surveys (SkS) and head CT imaging performed for SPA/child protection concerns. MAIN OUTCOME MEASURES: Incidence and severity of fractures identified on SkS; head injury (composed of incidence rates and ratios of skull fracture, intracranial haemorrhage (ICH) and hypoxic ischaemic injury (HII)) on head CT imaging; and ratio of antemortem and postmortem SkS. RESULTS: 1587 SkS were performed: 1282 (81%) antemortem, 762 (48%) male, and positive findings in 582 (37%). Median patient age was 6 months. There were 1.7 fractures/child prelockdown versus 1.1 fractures/child during lockdown. There was no difference between positive/negative SkS rates, the absolute ratio of antemortem/postmortem SkS or absolute numbers of head injury occurring between January 2018 and February 2020 and the lockdown period April-July 2020. Likewise, prelockdown incidence and rates of skull fracture 30/244 (12%), ICH 28/220 (13%) and HIE 10/205 (5%) were similar to lockdown, 142/1304 (11%), 171/1152 (15%) and 68/1089 (6%), respectively. CONCLUSION: The first UK COVID-19 lockdown did not lead to an increase in either the number of antemortem or postmortem radiological investigations performed for SPA, or the number or severity of fractures and intracranial injuries identified by these investigations.


Assuntos
COVID-19 , Maus-Tratos Infantis , Traumatismos Craniocerebrais , Fraturas Cranianas , COVID-19/epidemiologia , Criança , Maus-Tratos Infantis/diagnóstico , Controle de Doenças Transmissíveis , Traumatismos Craniocerebrais/diagnóstico por imagem , Traumatismos Craniocerebrais/epidemiologia , Traumatismos Craniocerebrais/etiologia , Feminino , Humanos , Lactente , Masculino , Abuso Físico , Estudos Retrospectivos , Fraturas Cranianas/diagnóstico por imagem , Fraturas Cranianas/epidemiologia , Fraturas Cranianas/etiologia , Reino Unido/epidemiologia
10.
Bioorg Med Chem Lett ; 21(19): 5939-43, 2011 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-21885277

RESUMO

The discovery of a series of highly potent and novel TLR7 agonist interferon inducers is described. Structure-activity relationships are presented, along with pharmacokinetic studies of a lead molecule from this series of N9-pyridylmethyl-8-oxo-3-deazapurine analogues. A rationale for the very high potency observed is offered. An investigation of the clearance mechanism of this class of compounds in rat was carried out, resulting in aldehyde oxidase mediated oxidation being identified as a key component of the high clearance observed. A possible solution to this problem is discussed.


Assuntos
Antivirais/síntese química , Antivirais/farmacologia , Hepacivirus/efeitos dos fármacos , Hepatite C/tratamento farmacológico , Interferons/agonistas , Receptor 7 Toll-Like/agonistas , Aldeído Oxidase/metabolismo , Animais , Antivirais/química , Antivirais/farmacocinética , Relação Dose-Resposta a Droga , Descoberta de Drogas , Avaliação Pré-Clínica de Medicamentos , Hepacivirus/fisiologia , Hepatite C/virologia , Humanos , Injeções Intravenosas , Indutores de Interferon/síntese química , Indutores de Interferon/química , Indutores de Interferon/farmacocinética , Indutores de Interferon/farmacologia , Microssomos Hepáticos/metabolismo , Terapia de Alvo Molecular , Peso Molecular , Purinas/síntese química , Purinas/metabolismo , Ratos , Solubilidade , Estereoisomerismo , Relação Estrutura-Atividade
12.
Cancer Genet ; 256-257: 77-80, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33957466

RESUMO

Pathogenic germ-line variants in GATA2 (GATA2-deficiency) can cause childhood myelodysplastic syndrome (MDS) and acute myeloid leukaemia (AML), and can be associated with distinct clinical syndromic features. However, penetrance and genotype-phenotype correlations are incompletely understood. Here we report on the clinically diverse features of three siblings affected by GATA2c.1021_1031del over an 18-year period, all initially presenting in childhood and adolescence with MDS and AML with monosomy 7 (-7), and one also with trisomy 8 (+8). The siblings inherited a GATA2c.1021_1031del from their father who remains asymptomatic in his sixth decade. The two younger sisters are well after unrelated haematopoietic stem cell transplantation (HSCT), while the first boy died of severe chronic lung disease after sibling HSCT from his youngest sister, who subsequently also developed GATA2-deficiency associated MDS. This family illustrates high penetrance with variable genotype/phenotype correlation within one generation with GATA2-deficiency. We surmise that the lung disease post sibling HSCT was also caused by the GATA2-deficiency. The experience with this family underlines the necessity for GATA2 analysis in all apparently sporadic childhood and teenage MDS and AML with -7 also in the absence of a family history or other clinical features, and rigorous genetic testing in siblings. Moreover, our findings support the arguments for pre-emptive HSCT in variant-carrying siblings.


Assuntos
Análise Citogenética , Fator de Transcrição GATA2/deficiência , Fator de Transcrição GATA2/genética , Leucemia Mieloide/genética , Penetrância , Irmãos , Adolescente , Adulto , Sequência de Bases , Criança , Evolução Fatal , Feminino , Humanos , Leucemia Mieloide/diagnóstico por imagem , Masculino , Linhagem
13.
Chem Commun (Camb) ; (19): 2218-20, 2008 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-18463745

RESUMO

Kinetic resolution of racemic C-3 substituted pyrrolidine-2,5-diones has been achieved for the first time using highly efficient oxazaborolidine catalysts derived from cis-1-amino-indan-2-ol.


Assuntos
Compostos Aza/química , Compostos de Boro/química , Succinimidas/química , Catálise , Indanos/química , Cinética , Estereoisomerismo , Succinimidas/isolamento & purificação
14.
Trauma Surg Acute Care Open ; 3(1): e000176, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29862323

RESUMO

Oversight of human subject research has evolved considerably since its inception. However, previous studies identified a lack of consistency of institutional review board (IRB) determination for the type of review required and whether informed consent is necessary, especially for prospective observational studies, which pose minimal risk of harm. We hypothesized that there is significant inter-institution variation in IRB requirements for the type of review and necessity of informed consent, especially for prospective observational trials without blood/tissue utilization. We also sought to describe investigators' and IRB members' attitudes toward the type of review and need for consent. Eastern Association for the Surgery of Trauma (EAST) and IRB members were sent an electronic survey on IRB review and informed consent requirement. We performed descriptive analyses as well as Fisher's exact test to determine differences between EAST and IRB members' responses. The response rate for EAST members from 113 institutions was 13.5%, whereas a convenience sample of IRB members from 14 institutions had a response rate of 64.4%. Requirement for full IRB review for retrospective studies using patient identifiers was reported by zero IRB member compared with 13.1% of EAST members (p=0.05). Regarding prospective observational trials without blood/tissue collection, 48.1% of EAST members reported their institutions required a full IRB review compared with 9.5% of IRB members (p=0.01). For prospective observational trials with blood/tissue collection, 80% of EAST members indicated requirement to submit a full IRB review compared with only 13.6% of IRB members (p<0.001). Most EAST members (78.6%) stated that informed consent is not ethically necessary in prospective observational trials without blood/tissue collection, whereas most IRB members thought that informed consent was ethically necessary (63.6%, p<0.001). There is significant variation in perception and practice regarding the level of review for prospective observational studies and whether informed consent is necessary. We recommend future interdisciplinary efforts between researchers and IRBs should occur to better standardize local IRB efforts. LEVEL OF EVIDENCE: IV.

15.
J Trauma Acute Care Surg ; 83(1): 165-169, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28452871

RESUMO

BACKGROUND: Mentorship programs in surgery are used to overcome barriers to clinical and academic productivity, research success, and work-life balance. We sought to determine if the Eastern Association for the Surgery of Trauma (EAST) Mentoring Program has met its goals of fostering academic and personal growth in young acute care surgeons. METHODS: We conducted a systematic program evaluation of EAST Mentoring Program's first 4 years. Demographic information was collected from EAST records, mentorship program applications, and mentee-mentor career development plans. We reviewed the career development plans for thematic commonalities and results of a structured, online questionnaire distributed since program inception. A mixed methods approach was used to better understand the program goals from both mentee and mentor perspectives, as well as attitudes and barriers regarding the perceived success of this career development program. RESULTS: During 2012 to 2015, 65 mentoring dyads were paired and 60 completed the program. Of 184 surveys distributed, 108 were returned (57% response rate). Respondents were evenly distributed between mentees and mentors (53 vs. 55, p = 0.768). In participant surveys, mentoring relationships were viewed to focus on research (45%), "sticky situations" (e.g., communication, work-life balance) (27%), education (18%), or administrative issues (10%). Mentees were more focused on research and education versus mentors (74% vs. 50%; p = 0.040). Mentees felt that goals were "always" or "usually" met versus mentors (89% vs. 77%; p = 0.096). Two barriers to successful mentorship included time and communication, with most pairs communicating by email. Most respondents (91%) planned to continue the relationship beyond the EAST Mentoring Program and recommended the experience to colleagues. CONCLUSION: Mentee satisfaction with the EAST Mentoring Program was high. Mentoring is a beneficial tool to promote success among EAST's young members, but differences exist between mentee and mentor perceptions. Revising communication expectations and time commitment to improve career development may help our young acute care surgeons.


Assuntos
Cirurgia Geral/educação , Tutoria , Traumatologia/educação , Docentes de Medicina , Bolsas de Estudo , Humanos , Internato e Residência , Satisfação Pessoal , Avaliação de Programas e Projetos de Saúde , Inquéritos e Questionários
16.
J Med Chem ; 56(4): 1730-8, 2013 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-23384403

RESUMO

Cyclic pyranopterin monophosphate (1), isolated from bacterial culture, has previously been shown to be effective in restoring normal function of molybdenum enzymes in molybdenum cofactor (MoCo)-deficient mice and human patients. Described here is a synthesis of 1 hydrobromide (1·HBr) employing in the key step a Viscontini reaction between 2,5,6-triamino-3,4-dihydropyrimidin-4-one dihydrochloride and D-galactose phenylhydrazone to give the pyranopterin (5aS,6R,7R,8R,9aR)-2-amino-6,7-dihydroxy-8-(hydroxymethyl)-3H,4H,5H,5aH,6H,7H,8H,9aH,10H-pyrano[3,2-g]pteridin-4-one (10) and establishing all four stereocenters found in 1. Compound 10, characterized spectroscopically and by X-ray crystallography, was transformed through a selectively protected tri-tert-butoxycarbonylamino intermediate into a highly crystalline tetracyclic phosphate ester (15). The latter underwent a Swern oxidation and then deprotection to give 1·HBr. Synthesized 1·HBr had in vitro efficacy comparable to that of 1 of bacterial origin as demonstrated by its enzymatic conversion into mature MoCo and subsequent reconstitution of MoCo-free human sulfite oxidase-molybdenum domain yielding a fully active enzyme. The described synthesis has the potential for scale up.


Assuntos
Coenzimas/química , Metaloproteínas/química , Compostos Organofosforados/síntese química , Pteridinas/química , Pterinas/síntese química , Coenzimas/metabolismo , Escherichia coli/metabolismo , Humanos , Metaloproteínas/metabolismo , Cofatores de Molibdênio , Compostos Organofosforados/química , Pteridinas/metabolismo , Pterinas/química , Transdução de Sinais , Estereoisomerismo
18.
Am J Pathol ; 172(1): 265-73, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18079439

RESUMO

The role of nitric oxide (NO) in regulating neutrophil migration has been investigated. Human neutrophil migration to interleukin (IL)-8 (1 nmol/L) was measured after a 1-hour incubation using a 96-well chemotaxis plate assay. The NO synthase inhibitor N(G)-nitro-l-arginine methyl ester (L-NAME) significantly (P < 0.001) enhanced IL-8-induced migration by up to 45%. Anti-CD18 significantly (P < 0.001) inhibited both IL-8-induced and L-NAME enhanced migration. Antibodies to L-selectin or PSGL-1 had no effect on IL-8-induced migration but prevented the increased migration to IL-8 induced by L-NAME. L-NAME induced generation of neutrophil-derived microparticles that was significantly (P < 0.01) greater than untreated neutrophils or D-NAME. This microparticle formation was dependent on calpain activity and superoxide production. Only microparticles from L-NAME and not untreated or D-NAME-treated neutrophils induced a significant (P < 0.01) increase in IL-8-induced migration and transendothelial migration. Pretreatment of microparticles with antibodies to L-selectin (DREG-200) or PSGL-1 (PL-1) significantly (P < 0.001) inhibited this effect. The ability of L-NAME-induced microparticles to enhance migration was found to be dependent on the number of microparticles produced and not an increase in microparticle surface L-selectin or PSGL-1 expression. These data show that NO can modulate neutrophil migration by regulating microparticle formation.


Assuntos
Regulação da Expressão Gênica , Neutrófilos/citologia , Óxido Nítrico/metabolismo , Antígenos CD18/biossíntese , Linhagem Celular , Movimento Celular , Células Endoteliais/citologia , Inibidores Enzimáticos/farmacologia , Citometria de Fluxo/métodos , Humanos , Interleucina-8/metabolismo , Microscopia Eletrônica , Modelos Biológicos , NG-Nitroarginina Metil Éster/farmacologia , Neutrófilos/metabolismo , Óxido Nítrico Sintase/metabolismo
19.
Bioorg Med Chem Lett ; 15(21): 4736-40, 2005 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-16140529

RESUMO

Both enantiomers of 20-fluorocamptothecin and the racemate have been prepared by total synthesis. The (R)-enantiomer is essentially inactive in a topoisomerase-I/DNA assay, while the (S)-enantiomer is much less active than (20S)-camptothecin. The lactone ring of 20-fluorocamptothecin hydrolyzes more rapidly than that of camptothecin in PBS. The results provide insight into the role of the 20-hydroxy group in the binding of camptothecin to topoisomerase-I and DNA.


Assuntos
Antineoplásicos/síntese química , Camptotecina/análogos & derivados , Inibidores da Topoisomerase I , Antineoplásicos/farmacologia , Camptotecina/síntese química , Camptotecina/química , Camptotecina/farmacologia , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/farmacologia , Humanos , Ligação de Hidrogênio , Hidrólise , Cinética , Estereoisomerismo , Relação Estrutura-Atividade
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