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1.
Am J Pathol ; 192(3): 484-502, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34896073

RESUMO

Leptin is an adipokine with roles in food intake and energy metabolism through its actions on neurons in the hypothalamus. The role of leptin in obesity and cardiovascular disorders is well documented. However, its influence on liver conditions such as cholestasis is poorly understood. The effects of exogenous leptin and leptin-neutralizing antibody on biliary hyperplasia, hepatic fibrosis, and inflammation in the multidrug resistance protein 2 knockout (Mdr2KO) mouse model of cholestasis were assessed by quantifying markers specific for cholangiocytes, activated hepatic stellate cells (HSCs), and cytokines. Serum and hepatic leptin were increased in Mdr2KO mice compared with FVB/NJ (FVBN) controls, and exogenous leptin enhanced biliary hyperplasia and liver fibrosis in Mdr2KO and FVBN mice. Leptin administration increased hepatic expression of C-C motif chemokine ligand 2 and IL-6 in Mdr2KO mice. In contrast, leptin-neutralizing antibody reduced intrahepatic bile duct mass and decreased HSC activation in Mdr2KO mice compared with FVBN controls. Sex-related differences were noted, with female Mdr2KO mice having more leptin than males. In cholangiocytes and LX2 cells in vitro, leptin increased phosphorylated Akt and stimulated cell proliferation. Leptin receptor siRNA and inhibitors of Akt phosphorylation impaired leptin-induced cell proliferation and proinflammatory cytokines. The current data suggest that leptin is abnormally increased in cholestatic mice, and excess leptin increases ductular reaction, hepatic fibrosis, and inflammation via leptin receptor-mediated phosphorylation of Akt in cholangiocytes and HSCs.


Assuntos
Colestase , Receptores para Leptina , Animais , Anticorpos Neutralizantes , Colestase/metabolismo , Citocinas/metabolismo , Modelos Animais de Doenças , Feminino , Células Estreladas do Fígado/metabolismo , Hiperplasia/patologia , Inflamação/patologia , Leptina/metabolismo , Leptina/farmacologia , Fígado/metabolismo , Cirrose Hepática/patologia , Masculino , Camundongos , Camundongos Knockout , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptores para Leptina/metabolismo
2.
Mov Disord ; 38(3): 474-479, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36598142

RESUMO

BACKGROUND: Cholinergic nucleus 4 (Ch4) degeneration is associated with cognitive impairment in Parkinson's disease and dementia with Lewy bodies, but it is unknown if Ch4 degeneration is also present in isolated rapid eye movement sleep behavior disorder (iRBD). OBJECTIVE: The aim was to determine if there is evidence of Ch4 degeneration in patients with iRBD and if it is associated with cognitive impairment. METHODS: We analyzed the clinical and neuropsychological data of 35 iRBD patients and 35 age- and sex-matched healthy controls. Regional gray matter density (GMD) was calculated for Ch4 using probabilistic maps applied to brain magnetic resonance imaging (MRI). RESULTS: Ch4 GMD was significantly lower in the iRBD group compared to controls (0.417 vs. 0.441, P = 0.02). Ch4 GMD was also found to be a significant predictor of letter number sequencing (ß-coefficient = 58.31, P = 0.026, 95% confidence interval [7.47, 109.15]), a measure of working memory. CONCLUSIONS: iRBD is associated with Ch4 degeneration, and Ch4 degeneration in iRBD is associated with impairment in working memory. © 2023 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.


Assuntos
Núcleo Basal de Meynert , Disfunção Cognitiva , Transtorno do Comportamento do Sono REM , Idoso , Feminino , Humanos , Masculino , Núcleo Basal de Meynert/diagnóstico por imagem , Núcleo Basal de Meynert/patologia , Disfunção Cognitiva/complicações , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/patologia , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/patologia , Hipocampo/diagnóstico por imagem , Hipocampo/patologia , Imageamento por Ressonância Magnética , Bulbo Olfatório/diagnóstico por imagem , Bulbo Olfatório/patologia , Transtorno do Comportamento do Sono REM/complicações , Transtorno do Comportamento do Sono REM/diagnóstico por imagem , Transtorno do Comportamento do Sono REM/patologia , Vias Neurais
3.
BMC Pediatr ; 23(1): 122, 2023 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-36932325

RESUMO

BACKGROUND: Liveborn infants with non-mosaic trisomy 22 are rarely described in the medical literature. Reported lifespan of these patients ranges from minutes to 3 years, with the absence of cardiac anomalies associated with longer-term survival. The landscape for offering cardiac surgery to patients with rare autosomal trisomies is currently evolving, as has been demonstrated recently in trisomies 13 and 18. However, limited available data on patients with rare autosomal trisomies provides a significant challenge in perinatal counseling, especially when there are options for surgical intervention. CASE PRESENTATION: In this case report, we describe an infant born at term with prenatally diagnosed apparently non-mosaic trisomy 22 and multiple cardiac anomalies, including a double outlet right ventricle, hypoplastic aortic valve and severe aortic arch hypoplasia, who underwent cardiac surgery. The decisions made by her family lending to her progress and survival to this day were made with a focus on the shared decision making model and support in the prenatal and perinatal period. We also review the published data on survival and quality of life after cardiac surgery in infants with rare trisomies. CONCLUSIONS: This patient is the only known case of apparently non-mosaic trisomy 22 in the literature who has undergone cardiac surgery with significant survival benefit. This case highlights the impact of using a shared decision making model when there is prognostic uncertainty.


Assuntos
Anormalidades Múltiplas , Cardiopatias Congênitas , Lactente , Gravidez , Feminino , Humanos , Trissomia , Qualidade de Vida , Tomada de Decisão Compartilhada , Cardiopatias Congênitas/genética , Cardiopatias Congênitas/cirurgia , Anormalidades Múltiplas/genética
4.
Bioorg Med Chem Lett ; 75: 128808, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-35609741

RESUMO

Novel bacterial topoisomerase inhibitors (NBTIs) are the newest members of gyrase inhibitor broad-spectrum antibacterial agents, represented by the most advanced member, gepotidacin, a 4-amino-piperidine linked NBTI, which is undergoing phase III clinical trials for treatment of urinary tract infections (UTI). We have extensively reported studies on oxabicyclooctane linked NBTIs, including AM-8722. The present study summarizes structure activity relationship (SAR) of AM-8722 leading to identification of 7-fluoro-1-cyanomethyl-1,5-naphthyridin-2-one based NBTI (16, AM-8888) with improved potency and spectrum (MIC values of 0.016-4 µg/mL), with Pseudomonas aeruginosa being the least sensitive strain (MIC 4 µg/mL).


Assuntos
Antibacterianos , Inibidores da Topoisomerase , Antibacterianos/química , Antibacterianos/farmacologia , DNA Girase/metabolismo , DNA Topoisomerase IV , Testes de Sensibilidade Microbiana , Staphylococcus aureus/metabolismo , Relação Estrutura-Atividade , Tioinosina/análogos & derivados , Inibidores da Topoisomerase II/química , Inibidores da Topoisomerase II/farmacologia , Inibidores da Topoisomerase/química , Inibidores da Topoisomerase/farmacologia
5.
Clin Oral Investig ; 25(9): 5273-5280, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33619633

RESUMO

OBJECTIVES: Although bowel symptoms are often predominant, inflammatory bowel disease (IBD) patients can have several oral manifestations. The aim of this study was to investigate the prevalence of dental caries and periodontal disease in patients with Crohn's disease (CD) and ulcerative colitis (UC) compared to an age and gender-matched control group of patients without IBD. MATERIAL AND METHODS: The DMFT (Decayed, Missing, Filled Teeth) scores and the DPSI (Dutch Periodontal Screening Index) of 229 IBD patients were retrieved from the electronic health record patient database axiUm at the Academic Centre for Dentistry Amsterdam (ACTA) and were compared to the DMFT scores and DPSI from age and gender-matched non-IBD patients from the same database. RESULTS: The total DMFT index was significantly higher in the IBD group compared to the control group. When CD and UC were analyzed separately, a statistically significant increased DMFT index was observed in CD patients but not in UC patients. The DPSI did not differ significantly between the IBD and non-IBD groups for each of the sextants. However, in every sextant, IBD patients were more frequently edentulous compared to the control patients. CONCLUSION: CD patients have significantly more dental health problems compared to a control group. Periodontal disease did not differ significantly between IBD and non-IBD groups as determined by the DPSI. CLINICAL RELEVANCE: It is important that IBD patients and physicians are instructed about the correlation between their disease and oral health problems. Strict oral hygiene and preventive dental care such as more frequent checkups should be emphasized by dental clinicians.


Assuntos
Colite Ulcerativa , Cárie Dentária , Doenças Inflamatórias Intestinais , Doenças Periodontais , Colite Ulcerativa/complicações , Colite Ulcerativa/epidemiologia , Cárie Dentária/epidemiologia , Humanos , Doenças Inflamatórias Intestinais/complicações , Doenças Inflamatórias Intestinais/epidemiologia , Doenças Periodontais/complicações , Doenças Periodontais/epidemiologia , Índice Periodontal
6.
Artigo em Inglês | MEDLINE | ID: mdl-30373794

RESUMO

Tedizolid phosphate, the prodrug of the active antibiotic tedizolid, is an oxazolidinone for the treatment of acute bacterial skin and skin structure infections. Studies in a mouse thigh infection model demonstrated that tedizolid has improved potency and pharmacokinetics/pharmacodynamics (PK/PD) compared with those of linezolid. Subsequent studies showed that the efficacy of tedizolid was enhanced in immunocompetent (IC) mice compared with neutropenic (immunosuppressed [IS]) mice, with stasis at clinically relevant doses being achieved only in the presence of granulocytes. The tedizolid label therefore contains a warning about its use in neutropenic patients. This study reevaluated the PK/PD of tedizolid and linezolid in the mouse thigh infection model in IC and IS mice using a methicillin-resistant Staphylococcus aureus (MRSA) strain (ATCC 33591) and a methicillin-susceptible S. aureus (MSSA) strain (ATCC 29213). The antistaphylococcal effect of doses ranging from 1 to 150 mg/kg of body weight tedizolid (once daily) or linezolid (twice daily) was determined at 24, 48, and 72 h after initiating treatment. In IC mice, stasis was achieved in the absence of antibiotics, and both tedizolid and linezolid reduced the burden further beyond a static effect. In IS mice, tedizolid achieved stasis against MRSA ATCC 33591 and MSSA ATCC 29213 at 72 h at a human clinical dose of 200 mg, severalfold lower than that in earlier studies. Linezolid achieved a static effect against MRSA ATCC 33591 in IS mice at a dose lower than that used clinically. This study demonstrates that, with time, both tedizolid and linezolid at clinically relevant exposures achieve stasis in neutropenic mice with an MRSA or MSSA thigh infection.


Assuntos
Antibacterianos/farmacologia , Linezolida/farmacologia , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Neutropenia/metabolismo , Organofosfatos/farmacologia , Oxazóis/farmacologia , Infecções Cutâneas Estafilocócicas/tratamento farmacológico , Animais , Antibacterianos/farmacocinética , Modelos Animais de Doenças , Linezolida/farmacocinética , Camundongos , Testes de Sensibilidade Microbiana , Organofosfatos/farmacocinética , Oxazóis/farmacocinética , Infecções Cutâneas Estafilocócicas/microbiologia
7.
Biotechnol Bioeng ; 116(9): 2393-2411, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31112285

RESUMO

The new and rapid advancement in the complexity of biologics drug discovery has been driven by a deeper understanding of biological systems combined with innovative new therapeutic modalities, paving the way to breakthrough therapies for previously intractable diseases. These exciting times in biomedical innovation require the development of novel technologies to facilitate the sophisticated, multifaceted, high-paced workflows necessary to support modern large molecule drug discovery. A high-level aspiration is a true integration of "lab-on-a-chip" methods that vastly miniaturize cellulmical experiments could transform the speed, cost, and success of multiple workstreams in biologics development. Several microscale bioprocess technologies have been established that incrementally address these needs, yet each is inflexibly designed for a very specific process thus limiting an integrated holistic application. A more fully integrated nanoscale approach that incorporates manipulation, culture, analytics, and traceable digital record keeping of thousands of single cells in a relevant nanoenvironment would be a transformative technology capable of keeping pace with today's rapid and complex drug discovery demands. The recent advent of optical manipulation of cells using light-induced electrokinetics with micro- and nanoscale cell culture is poised to revolutionize both fundamental and applied biological research. In this review, we summarize the current state of the art for optical manipulation techniques and discuss emerging biological applications of this technology. In particular, we focus on promising prospects for drug discovery workflows, including antibody discovery, bioassay development, antibody engineering, and cell line development, which are enabled by the automation and industrialization of an integrated optoelectronic single-cell manipulation and culture platform. Continued development of such platforms will be well positioned to overcome many of the challenges currently associated with fragmented, low-throughput bioprocess workflows in biopharma and life science research.


Assuntos
Automação , Produtos Biológicos , Descoberta de Drogas , Dispositivos Lab-On-A-Chip , Humanos
8.
Vet Surg ; 48(1): 42-49, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30446990

RESUMO

OBJECTIVE: To compare mechanisms of and pressures at failure of 4 methods of securing 2 types of cellophane bands around a vein. STUDY DESIGN: Ex vivo mechanical evaluation. METHODS: Cellophane bands composed of 3 or 4 layers were applied around a cadaveric external jugular vein (EJV) to create 25% or 50% attenuation. These bands were secured with a medium or medium-large polymer locking ligation clip (PLLC), or a medium or medium-large titanium ligation clip (TLC). Sterile saline 0.9% was instilled into the lumen of the EJV until a pressure of 100 mm Hg was reached. Failure mechanism and luminal pressure at failure were compared between groups. RESULTS: Medium clips failed less often than medium-large clips (P < .001) and consistently sustained 100 mm Hg without failing. Three-layer cellophane bands were 4.1 times more likely to fail than 4-layer bands (P = .003, CI 1.6-10.2) and failed at lower pressures (28.32 ± 3.59 mm Hg and 44.81 ± 6.51 mm Hg, respectively, P = .027). Failure rates of the cellophane band constructs did not differ whether secured with PLLC or with TLC (P = .635) or with 25% vs 50% attenuation (P = .780). CONCLUSION: A single medium clip withstood physiological forces and secured a cellophane band at up to 50% attenuation. A 3-layer cellophane band was more likely to fail compared with a 4-layer cellophane band. CLINICAL SIGNIFICANCE: These ex vivo results provide evidence to support the application of a 4-layer cellophane band secured with a single medium PLLC or TLC for portosystemic shunt attenuation. A single medium PLLC should be used to eliminate computed tomography artifacts during postoperative evaluation of shunt closure.


Assuntos
Celofane/uso terapêutico , Cães/anormalidades , Cães/cirurgia , Sistema Porta/anormalidades , Cirurgia Veterinária/métodos , Animais , Cadáver , Feminino , Ligadura/instrumentação , Ligadura/veterinária , Masculino , Sistema Porta/cirurgia
9.
Vet Surg ; 47(6): 861-871, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30091145

RESUMO

OBJECTIVE: To describe normal antebrachiocarpal joint kinematic motion during axial loading and to describe the effect of palmar radiocarpal ligament (PRL) and palmar ulnocarpal ligament (PUL) transection on this motion. SAMPLE POPULATION: Ten forelimbs from 5 adult greyhound cadavers. METHODS: Limbs were placed in a custom jig and computed tomography images of limbs were obtained in neutral and extended positions. The translation and rotation of the intermedioradiocarpal bone (RCB), ulnar carpal bone, and accessory carpal bone were described relative to the radius through rigid body motion analysis. Kinematic and load analysis was repeated after sequential transection of the PRL and the PUL. RESULTS: Sagittal plane extension with a lesser component of valgus motion was found in all evaluated carpal bones. RCB supination was also detected during extension. Compared with the normal intact limb, transection of either or both the PRL and the PUL did not influence mean translation or rotation data or limb load. However, the transection of the PRL and the PUL increased the variance in rotation data compared with intact limb. CONCLUSION: This study describes normal antebrachiocarpal kinematics as a foundation for determining carpal functional units. During axial loading, the PRL and the PUL may function to guide consistent motion in extension and flexion as well as pronation and supination. CLINICAL SIGNIFICANCE: Three-dimensional carpal kinematic analyses may improve our understanding of carpal injury and facilitate the development of novel treatments techniques.


Assuntos
Carpo Animal/diagnóstico por imagem , Cães/anatomia & histologia , Membro Anterior/diagnóstico por imagem , Ligamentos Articulares/fisiologia , Amplitude de Movimento Articular/fisiologia , Suporte de Carga , Animais , Fenômenos Biomecânicos , Tomografia Computadorizada por Raios X/veterinária
10.
J Vet Med Educ ; 45(2): 250-254, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-28885872

RESUMO

Tumors of the skin and subcutaneous tissues are an important cause of morbidity and mortality in small animals. In many cases, surgical excision is an essential component of successful therapy and it should be performed in a specific way based on the type and grade of the tumor. Students require adequate training to develop both clinical decision-making skills and technical surgical skills, which we believe contribute to optimal clinical results. We have developed an inexpensive and simple technique that aims to replicate a naturally occurring subcutaneous tumor and allows trainees to plan and perform three common surgical procedures: incisional biopsy, marginal excision, and wide surgical excision. Artificial tumors were created by subcutaneous injection of a heated, oil-based solution that adhered to surrounding tissue as it solidified. Simulated masses were successfully created in all specimens. Many students performed the exercises with technical proficiency; however, some technical errors were identified and provided an opportunity to discuss the challenges of and solutions to several of these situations. This exercise may be a valuable addition to the veterinary curriculum, aiding student development of both technical skills and knowledge in the field of surgical oncology.


Assuntos
Doenças do Gato/cirurgia , Educação em Veterinária , Neoplasias/veterinária , Oncologia Cirúrgica/educação , Animais , Gatos , Competência Clínica , Humanos , Neoplasias/cirurgia , Estudantes de Medicina
11.
Anal Biochem ; 518: 9-15, 2017 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-27815077

RESUMO

The emergence of methicillin-resistant Staphylococcus aureus (MRSA) has created an urgent need for new therapeutic agents capable of combating this threat. We have previously reported on the discovery of novel inhibitors targeting enzymes involved in the biosynthesis of wall teichoic acid (WTA) and demonstrated that these agents can restore ß-lactam efficacy against MRSA. In those previous reports pathway engagement of inhibitors was demonstrated by reduction in WTA levels measured by polyacrylamide gel electrophoresis. To enable a more rigorous analysis of these inhibitors we sought to develop a quantitative method for measuring whole-cell reductions in WTA. Herein we describe a robust methodology for hydrolyzing polymeric WTA to the monomeric component ribitol-N-acetylglucosamine coupled with measurement by LC-MS/MS. Critical elements of the protocol were found to include the time and temperature of hydrofluoric acid-mediated hydrolysis of polymeric WTA and optimization of these parameters is fully described. Most significantly, the assay enabled accurate and reproducible measurement of depletion EC50s for tunicamycin and representatives from the novel class of TarO inhibitors, the tarocins. The method described can readily be adapted to quantifying levels of WTA in tissue homogenates from a murine model of infection, highlighting the applicability for both in vitro and in vivo characterizations.


Assuntos
Espectrometria de Massas/métodos , Staphylococcus aureus Resistente à Meticilina/metabolismo , Ácidos Teicoicos/metabolismo , Cromatografia Líquida/métodos , Staphylococcus aureus Resistente à Meticilina/química , Ácidos Teicoicos/química , Tunicamicina/farmacologia
12.
Optom Vis Sci ; 94(3): 387-394, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28005683

RESUMO

PURPOSE: To determine the association between changes in body length with ocular refraction, corneal radii, axial length, and lens thickness in two different mouse strains. METHODS: Body length, ocular refraction, corneal radii, axial length, and lens thickness were measured for two inbred mouse strains: 129S1/SvJ (n = 7) and C57BL/6 J (n = 10) from 4 to 12 weeks of age. Body length, from tip of nose to base of tail, was obtained using a digital camera. Biometric parameters, corneal radii, and refractions were measured using spectral-domain optical coherence tomography, automated keratometry, and infrared photorefraction, respectively. A mixed-model ANOVA was performed to examine the changes in ocular parameters as a function of body length and strain in mice controlling for age, gender, and weight over time. RESULTS: C57BL/6J mice had significantly longer body length (average body length at 10 weeks, 8.60 ± 0.06 cm) compared to 129S1/SvJ mice (8.31 ± 0.05 cm) during development (P < .001). C57BL/6J mice had significantly hyperopic refractions compared to 129S1/SvJ mice across age (mean refraction at 10 weeks, 129S1/SvJ: +0.99 ± 0.44D vs. C57BL/6J: +6.24 ± 0.38D, P < .001). Corneal radius of curvature, axial length, and lens thickness (except 10 weeks lens thickness) were similar between the two strains throughout the measurement. In the mixed-model ANOVA, changes in body length showed an independent and significant association with the changes in refraction (P = .002) and corneal radii (P = .016) for each mouse strain. No significant association was found between the changes in axial length (P = .925) or lens thickness (P = .973) as a function of body length and strain. CONCLUSIONS: Changes in body length are significantly associated with the changes in ocular refraction and corneal radii in different mouse strains. Future studies are needed to determine if the association between body length and ocular refraction are related to changes in corneal curvature in mice.


Assuntos
Comprimento Axial do Olho/fisiologia , Tamanho Corporal/fisiologia , Córnea/anatomia & histologia , Cristalino/anatomia & histologia , Refração Ocular/fisiologia , Erros de Refração/fisiopatologia , Animais , Biometria/métodos , Feminino , Masculino , Camundongos , Camundongos da Linhagem 129 , Camundongos Endogâmicos C57BL , Tomografia de Coerência Óptica
13.
J Biomech Eng ; 139(10)2017 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-28787471

RESUMO

Radiographic data, including computed tomography (CT) and planar X-ray, is increasingly used for human and animal kinematic studies. There is a tendency toward using as high-resolution imaging as possible. Higher resolution imaging is one factor (in conjunction with the reconstruction algorithm), which may increase the precision of reconstructed three-dimensional (3D) surface models in representing true bone shape. However, to date no study has tested the effects of scan resolution, threshold, and 3D model reconstruction algorithm on the accuracy of bone kinematic results. The present study uses a novel method to do this where canine tarsal bones were positioned on a radiolucent Lego™ board and scanned before and after undergoing known translations and/or rotations. The digital imaging and communications in medicine (DICOM) images were acquired using two different CT scanning resolutions and processed using three different segmentation threshold levels and three different reconstruction algorithms. Using one bone as the reference bone, an iterative closest point (ICP) algorithm was used to register bones to a global co-ordinate system and allow measurement of other bone kinematics in terms of translations and rotations in and around the x-, y-, and z-axes. The measured kinematics were compared to the "known" kinematics, which were obtained from the Lego™ board's manufacturing standards and tolerances, to give accuracy error metrics for all bones. The results showed error in accuracy of measured kinematics was at subvoxel levels (less than 0.5 mm). Despite altering the volume and surface area of the 3D bone models, variation in resolution, segmentation threshold and reconstruction algorithm had no significant influence upon the accuracy of the calculated tarsal bone kinematics.


Assuntos
Algoritmos , Imageamento Tridimensional , Fenômenos Mecânicos , Tomografia Computadorizada por Raios X , Animais , Fenômenos Biomecânicos , Bovinos , Ossos do Tarso/diagnóstico por imagem
14.
Proc Natl Acad Sci U S A ; 111(41): 14788-93, 2014 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-25267614

RESUMO

Aggressive neuroendocrine lung cancers, including small cell lung cancer (SCLC) and non-small cell lung cancer (NSCLC), represent an understudied tumor subset that accounts for approximately 40,000 new lung cancer cases per year in the United States. No targeted therapy exists for these tumors. We determined that achaete-scute homolog 1 (ASCL1), a transcription factor required for proper development of pulmonary neuroendocrine cells, is essential for the survival of a majority of lung cancers (both SCLC and NSCLC) with neuroendocrine features. By combining whole-genome microarray expression analysis performed on lung cancer cell lines with ChIP-Seq data designed to identify conserved transcriptional targets of ASCL1, we discovered an ASCL1 target 72-gene expression signature that (i) identifies neuroendocrine differentiation in NSCLC cell lines, (ii) is predictive of poor prognosis in resected NSCLC specimens from three datasets, and (iii) represents novel "druggable" targets. Among these druggable targets is B-cell CLL/lymphoma 2, which when pharmacologically inhibited stops ASCL1-dependent tumor growth in vitro and in vivo and represents a proof-of-principle ASCL1 downstream target gene. Analysis of downstream targets of ASCL1 represents an important advance in the development of targeted therapy for the neuroendocrine class of lung cancers, providing a significant step forward in the understanding and therapeutic targeting of the molecular vulnerabilities of neuroendocrine lung cancer.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem da Célula , Tumores Neuroendócrinos/genética , Oncogenes , Carcinoma de Pequenas Células do Pulmão/genética , Adenocarcinoma/genética , Adenocarcinoma/patologia , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Carcinoma Pulmonar de Células não Pequenas/genética , Linhagem Celular Tumoral , Sobrevivência Celular , Imunoprecipitação da Cromatina , Regulação Neoplásica da Expressão Gênica , Humanos , Imuno-Histoquímica , Tumores Neuroendócrinos/patologia , Prognóstico , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Carcinoma de Pequenas Células do Pulmão/patologia
15.
Antimicrob Agents Chemother ; 60(8): 4830-9, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27246784

RESUMO

Oxabicyclooctane-linked novel bacterial topoisomerase inhibitors (NBTIs) represent a new class of recently described antibacterial agents with broad-spectrum activity. NBTIs dually inhibit the clinically validated bacterial targets DNA gyrase and topoisomerase IV and have been shown to bind distinctly from known classes of antibacterial agents directed against these targets. Herein we report the molecular, cellular, and in vivo characterization of AM-8722 as a representative N-alkylated-1,5-naphthyridone left-hand-side-substituted NBTI. Consistent with its mode of action, macromolecular labeling studies revealed a specific effect of AM-8722 to dose dependently inhibit bacterial DNA synthesis. AM-8722 displayed greater intrinsic enzymatic potency than levofloxacin versus both DNA gyrase and topoisomerase IV from Staphylococcus aureus and Escherichia coli and displayed selectivity against human topoisomerase II. AM-8722 was rapidly bactericidal and exhibited whole-cell activity versus a range of Gram-negative and Gram-positive organisms, with no whole-cell potency shift due to the presence of DNA or human serum. Frequency-of-resistance studies demonstrated an acceptable rate of resistance emergence in vitro at concentrations 16- to 32-fold the MIC. AM-8722 displayed acceptable pharmacokinetic properties and was shown to be efficacious in mouse models of bacterial septicemia. Overall, AM-8722 is a selective and potent NBTI that displays broad-spectrum antimicrobial activity in vitro and in vivo.


Assuntos
Antibacterianos/farmacologia , Ciclo-Octanos/farmacologia , DNA Girase/metabolismo , DNA Topoisomerase IV/antagonistas & inibidores , DNA Topoisomerases Tipo II/metabolismo , Inibidores da Topoisomerase II/farmacologia , Animais , Linhagem Celular , DNA Bacteriano/genética , Cães , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Infecções por Escherichia coli/tratamento farmacológico , Humanos , Camundongos , Testes de Sensibilidade Microbiana , Ratos , Ratos Wistar , Infecções Estafilocócicas/tratamento farmacológico , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/genética
16.
Am J Med Genet A ; 170(6): 1580-4, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26955893

RESUMO

Pathogenic variants in the mitofusin 2 gene (MFN2) are the most common cause of autosomal dominant Charcot-Marie-Tooth (CMT2) disease, which is typically characterized by axonal sensorimotor neuropathy. We report on a 7-month-old white female with hypotonia, motor delay, distal weakness, and motor/sensory axonal neuropathy in which next-generation sequencing analysis identified compound heterozygous pathogenic variants (c.2054_2069_1170del and c.392A>G) in MFN2. A review of the literature reveals that sporadic and familial cases of compound heterozygous or homozygous pathogenic MFN2 variants have been infrequently described, which indicates that MFN2 can also be inherited in a recessive manner. This case highlights several clinical findings not typically associated with MFN2 pathogenic variants, including young age of onset and rapidly progressing diaphragmatic paresis that necessitated tracheostomy and mechanical ventilation, and adds to the growing list of features identified in autosomal recessive MFN2-related CMT2. Our patient with MFN2-related CMT2 expands the clinical and mutational spectrum of individuals with autosomal recessive CMT2 and identifies a new clinical feature that warrants further observation. © 2016 Wiley Periodicals, Inc.


Assuntos
Doença de Charcot-Marie-Tooth/diagnóstico , Doença de Charcot-Marie-Tooth/genética , Diafragma/fisiopatologia , GTP Fosfo-Hidrolases/genética , Genes Recessivos , Proteínas Mitocondriais/genética , Debilidade Muscular/genética , Mutação , Alelos , Feminino , Estudos de Associação Genética , Genótipo , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Lactente , Linhagem , Fenótipo
17.
Bioorg Med Chem Lett ; 26(16): 3999-4002, 2016 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-27436582

RESUMO

The widespread emergence of methicillin-resistant Staphylococcus aureus (MRSA) has dramatically eroded the efficacy of current ß-lactam antibiotics and created an urgent need for novel treatment options. Using an S. aureus phenotypic screening strategy, we have identified small molecule early stage wall teichoic acid (WTA) pathway-specific inhibitors predicted to be chemically synergistic with ß-lactams. These previously disclosed inhibitors, termed tarocins, demonstrate by genetic and biochemical means inhibition of TarO, the first step in WTA biosynthesis. Tarocins demonstrate potent bactericidal synergy in combination with broad spectrum ß-lactam antibiotics across diverse clinical isolates of methicillin-resistant Staphylococci. The synthesis and structure-activity relationships (SAR) of a tarocin series will be detailed. Tarocins and other WTA inhibitors may provide a rational strategy to develop Gram-positive bactericidal ß-lactam combination agents active against methicillin-resistant Staphylococci.


Assuntos
Antibacterianos/química , Ácidos Teicoicos/metabolismo , beta-Lactamas/antagonistas & inibidores , Antibacterianos/síntese química , Antibacterianos/farmacologia , Parede Celular/efeitos dos fármacos , Parede Celular/metabolismo , Avaliação Pré-Clínica de Medicamentos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Staphylococcus aureus/efeitos dos fármacos , Relação Estrutura-Atividade , beta-Lactamas/metabolismo
18.
Bioorg Med Chem Lett ; 26(19): 4743-4747, 2016 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-27575474

RESUMO

A series of benzimidazole analogs have been synthesized to improve the profile of the previous lead compounds tarocin B and 1. The syntheses, structure-activity relationships, and selected biochemical data of these analogs are described. The optimization efforts allowed the identification of 21, a fluoro-substituted benzimidazole, exhibiting potent TarO inhibitory activity and typical profile for a wall teichoic acid (WTA) biosynthesis inhibitor. Compound 21 displayed a potent synergistic and bactericidal effect in combination with imipenem against diverse methicillin-resistant Staphylococci.


Assuntos
Antibacterianos/farmacologia , Benzimidazóis/farmacologia , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Ácidos Teicoicos/antagonistas & inibidores , Animais , Antibacterianos/química , Benzimidazóis/química , Testes de Sensibilidade Microbiana , Ratos , Relação Estrutura-Atividade , Ácidos Teicoicos/biossíntese
19.
Nucleic Acids Res ; 42(Web Server issue): W449-60, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24906883

RESUMO

For the Library of Integrated Network-based Cellular Signatures (LINCS) project many gene expression signatures using the L1000 technology have been produced. The L1000 technology is a cost-effective method to profile gene expression in large scale. LINCS Canvas Browser (LCB) is an interactive HTML5 web-based software application that facilitates querying, browsing and interrogating many of the currently available LINCS L1000 data. LCB implements two compacted layered canvases, one to visualize clustered L1000 expression data, and the other to display enrichment analysis results using 30 different gene set libraries. Clicking on an experimental condition highlights gene-sets enriched for the differentially expressed genes from the selected experiment. A search interface allows users to input gene lists and query them against over 100 000 conditions to find the top matching experiments. The tool integrates many resources for an unprecedented potential for new discoveries in systems biology and systems pharmacology. The LCB application is available at http://www.maayanlab.net/LINCS/LCB. Customized versions will be made part of the http://lincscloud.org and http://lincs.hms.harvard.edu websites.


Assuntos
Perfilação da Expressão Gênica/métodos , Software , Antineoplásicos/farmacologia , Neoplasias da Mama/genética , Feminino , Humanos , Interleucinas/farmacologia , Internet , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Interface Usuário-Computador
20.
Hum Mutat ; 36(4): 454-62, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25655089

RESUMO

Cornelia de Lange syndrome (CdLS) is characterized by facial dysmorphism, growth failure, intellectual disability, limb malformations, and multiple organ involvement. Mutations in five genes, encoding subunits of the cohesin complex (SMC1A, SMC3, RAD21) and its regulators (NIPBL, HDAC8), account for at least 70% of patients with CdLS or CdLS-like phenotypes. To date, only the clinical features from a single CdLS patient with SMC3 mutation has been published. Here, we report the efforts of an international research and clinical collaboration to provide clinical comparison of 16 patients with CdLS-like features caused by mutations in SMC3. Modeling of the mutation effects on protein structure suggests a dominant-negative effect on the multimeric cohesin complex. When compared with typical CdLS, many SMC3-associated phenotypes are also characterized by postnatal microcephaly but with a less distinctive craniofacial appearance, a milder prenatal growth retardation that worsens in childhood, few congenital heart defects, and an absence of limb deficiencies. While most mutations are unique, two unrelated affected individuals shared the same mutation but presented with different phenotypes. This work confirms that de novo SMC3 mutations account for ∼ 1%-2% of CdLS-like phenotypes.


Assuntos
Proteínas de Ciclo Celular/genética , Proteoglicanas de Sulfatos de Condroitina/genética , Proteínas Cromossômicas não Histona/genética , Síndrome de Cornélia de Lange/diagnóstico , Síndrome de Cornélia de Lange/genética , Heterozigoto , Mutação , Fenótipo , Alelos , Estudos de Coortes , Análise Mutacional de DNA , Exoma , Fácies , Feminino , Genótipo , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino
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