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1.
Int J Mol Sci ; 24(11)2023 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-37298099

RESUMO

Urothelial cancer (UC) is a common malignancy and its development is associated with arsenic exposure. Around 25% of diagnosed UC cases are muscle invasive (MIUC) and are frequently associated with squamous differentiation. These patients commonly develop cisplatin (CIS) resistance and have poor prognosis. SOX2 expression is correlated to reduced overall and disease-free survival in UC. SOX2 drives malignant stemness and proliferation in UC cells and is associated with development of CIS resistance. Using quantitative proteomics, we identified that SOX2 was overexpressed in three arsenite (As3+)-transformed UROtsa cell lines. We hypothesized that inhibition of SOX2 would reduce stemness and increase sensitivity to CIS in the As3+-transformed cells. Pevonedistat (PVD) is a neddylation inhibitor and is a potent inhibitor of SOX2. We treated non-transformed parent and As3+-transformed cells with PVD, CIS, or in combination and monitored cell growth, sphere forming abilities, apoptosis, and gene/protein expression. PVD treatment alone caused morphological changes, reduced cell growth, attenuated sphere formation, induced apoptosis, and elevated the expression of terminal differentiation markers. However, the combined treatment of PVD with CIS significantly elevated the expression of terminal differentiation markers and eventually led to more cell death than either solo treatment. Aside from a reduced proliferation rate, these effects were not seen in the parent. Further research is needed to explore the potential use of PVD with CIS as a differentiation therapy or alternative treatment for MIUC tumors that may have become resistant to CIS.


Assuntos
Arsenitos , Carcinoma de Células de Transição , Neoplasias da Bexiga Urinária , Humanos , Arsenitos/farmacologia , Neoplasias da Bexiga Urinária/metabolismo , Carcinoma de Células de Transição/patologia , Cisplatino , Antígenos de Diferenciação , Proliferação de Células , Apoptose , Linhagem Celular Tumoral , Fatores de Transcrição SOXB1/genética , Fatores de Transcrição SOXB1/metabolismo
2.
Artigo em Inglês | MEDLINE | ID: mdl-37195083

RESUMO

ABSTRACT: A variety of changes, many predictable and others more aberrant, occur during the postmortem interval. A number of these changes are largely influenced by various environmental conditions. We describe 3 cases of an unusual postmortem change associated with prolonged sunlight exposure in both frozen and nonfrozen individuals. In each case, very well-delineated, dark tanning lines were present where clothing or another object blocked sunlight. This change appears distinct from mummification and scant literature references that describe a tanned skin transformation in cases associated with burials in high salt-containing bogs. Collectively, the cases highlight a novel postmortem phenomenon known as postmortem tanning. The potential mechanism(s) of this change is discussed within the context of known observations. Increased recognition and knowledge of postmortem tanning are exceedingly important in assessing how this change may assist in postmortem scene analysis.

3.
Int J Mol Sci ; 23(20)2022 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-36293167

RESUMO

The bladder is a target organ for inorganic arsenic, a carcinogen and common environmental contaminant found in soil and water. Urothelial carcinoma (UC) is the most common type of bladder cancer (BC) that develops into papillary or non-papillary tumors. Papillary tumors are mostly non-muscle invasive (NMIUC), easier treated, and have a better prognosis. Urothelial carcinoma can be molecularly sub-typed as luminal or basal, with papillary tumors generally falling into the luminal category and basal tumors exclusively forming muscle invasive urothelial carcinomas (MIUC). It is unclear why some UCs develop more aggressive basal phenotypes. We hypothesized that chronic arsenic exposure of a papillary luminal bladder cancer would lead to the development of basal characteristics and increase in invasiveness. We treated the human papillary bladder cancer cell line RT4 with 1 µM arsenite (As3+) for twenty passages. Throughout the study, key luminal and basal gene/protein markers in the exposed cells were evaluated and at passage twenty, the cells were injected into athymic mice to evaluate tumor histology and measure protein markers using immunohistochemistry. Our data indicates that chronic As3+- treatment altered cellular morphology and decreased several luminal markers in cell culture. The histology of the tumors generated from the As3+-exposed cells was similar to the parent (non-treated) however, they appeared to be more invasive in the liver and displayed elevated levels of some basal markers. Our study demonstrates that chronic As3+ exposure is able to convert a non-invasive papillary bladder cancer to an invasive form that acquires some basal characteristics.


Assuntos
Arsênio , Arsenitos , Carcinoma de Células de Transição , Neoplasias da Bexiga Urinária , Camundongos , Animais , Humanos , Carcinoma de Células de Transição/metabolismo , Neoplasias da Bexiga Urinária/metabolismo , Arsênio/toxicidade , Camundongos Nus , Carcinógenos , Solo , Água , Biomarcadores Tumorais/metabolismo
4.
Pediatrics ; 148(4)2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34544849

RESUMO

After a sudden infant death, parents and caregivers need accurate and open communication about why their infant died. Communicating tragic news about a child's death to families and caregivers is difficult. Shared and consistent terminology is essential for pediatricians, other physicians, and nonphysician clinicians to improve communication with families and among themselves. When families do not have complete information about why their child died, pediatricians will not be able to support them through the process and make appropriate referrals for pediatric specialty and mental health care. Families can only speculate about the cause and may blame themselves or others for the infant's death. The terminology used to describe infant deaths that occur suddenly and unexpectedly includes an assortment of terms that vary across and among pediatrician, other physician, or nonphysician clinician disciplines. Having consistent terminology is critical to improve the understanding of the etiology, pathophysiology, and epidemiology of these deaths and communicate with families. A lack of consistent terminology also makes it difficult to reliably monitor trends in mortality and hampers the ability to develop effective interventions. This report describes the history of sudden infant death terminology and summarizes the debate over the terminology and the resulting diagnostic shift of these deaths. This information is to assist pediatricians, other physicians, and nonphysician clinicians in caring for families during this difficult time. The importance of consistent terminology is outlined, followed by a summary of progress toward consensus. Recommendations for pediatricians, other physicians, and nonphysician clinicians are proposed.


Assuntos
Causas de Morte , Classificação Internacional de Doenças , Morte Súbita do Lactente , Terminologia como Assunto , Autopsia , Medicina Legal/normas , História do Século XX , Humanos , Lactente , Fatores de Risco
5.
Toxics ; 9(5)2021 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-33923173

RESUMO

We explored the potential role of zinc (Zn) and zinc transporters in protection against cytotoxicity of cadmium (Cd) in a cell culture model of human urothelium, named UROtsa. We used real-time qRT-PCR to quantify transcript levels of 19 Zn transporters of the Zrt-/Irt-like protein (ZIP) and ZnT gene families that were expressed in UROtsa cells and were altered by Cd exposure. Cd as low as 0.1 µM induced expression of ZnT1, known to mediate efflux of Zn and Cd. Loss of cell viability by 57% was seen 24 h after exposure to 2.5 µM Cd. Exposure to 2.5 µM Cd together with 10-50 µM Zn prevented loss of cell viability by 66%. Pretreatment of the UROtsa cells with an inhibitor of glutathione biosynthesis (buthionine sulfoximine) diminished ZnT1 induction by Cd with a resultant increase in sensitivity to Cd cytotoxicity. Conversely, pretreatment of UROtsa cells with an inhibitor of DNA methylation, 5-aza-2'-deoxycytidine (aza-dC) did not change the extent of ZnT1 induction by Cd. The induced expression of ZnT1 that remained impervious in cells treated with aza-dC coincided with resistance to Cd cytotoxicity. Therefore, expression of ZnT1 efflux transporter and Cd toxicity in UROtsa cells could be modulated, in part, by DNA methylation and glutathione biosynthesis. Induced expression of ZnT1 may be a viable mechanistic approach to mitigating cytotoxicity of Cd.

6.
Front Neurol ; 12: 636668, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33776893

RESUMO

Pre-natal exposures to nicotine and alcohol are known risk factors for sudden infant death syndrome (SIDS), the leading cause of post-neonatal infant mortality. Here, we present data on nicotinic receptor binding, as determined by 125I-epibatidine receptor autoradiography, in the brainstems of infants dying of SIDS and of other known causes of death collected from the Safe Passage Study, a prospective, multicenter study with clinical sites in Cape Town, South Africa and 5 United States sites, including 2 American Indian Reservations. We examined 15 pons and medulla regions related to cardiovascular control and arousal in infants dying of SIDS (n = 12) and infants dying from known causes (n = 20, 10 pre-discharge from time of birth, 10 post-discharge). Overall, there was a developmental decrease in 125I-epibatidine binding with increasing postconceptional age in 5 medullary sites [raphe obscurus, gigantocellularis, paragigantocellularis, centralis, and dorsal accessory olive (p = 0.0002-0.03)], three of which are nuclei containing serotonin cells. Comparing SIDS with post-discharge known cause of death (post-KCOD) controls, we found significant decreased binding in SIDS in the nucleus pontis oralis (p = 0.02), a critical component of the cholinergic ascending arousal system of the rostral pons (post-KCOD, 12.1 ± 0.9 fmol/mg and SIDS, 9.1 ± 0.78 fmol/mg). In addition, we found an effect of maternal smoking in SIDS (n = 11) combined with post-KCOD controls (n = 8) on the raphe obscurus (p = 0.01), gigantocellularis (p = 0.02), and the paragigantocellularis (p = 0.002), three medullary sites found in this study to have decreased binding with age and found in previous studies to have abnormal indices of serotonin neurotransmission in SIDS infants. At these sites, 125I-epibatidine binding increased with increasing cigarettes per week. We found no effect of maternal drinking on 125I-epibatidine binding at any site measured. Taken together, these data support changes in nicotinic receptor binding related to development, cause of death, and exposure to maternal cigarette smoking. These data present new evidence in a prospective study supporting the roles of developmental factors, as well as adverse exposure on nicotinic receptors, in serotonergic nuclei of the rostral medulla-a finding that highlights the interwoven and complex relationship between acetylcholine (via nicotinic receptors) and serotonergic neurotransmission in the medulla.

7.
PLoS One ; 15(8): e0237976, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32822399

RESUMO

Environmental exposure to arsenite (As3+) has a strong association with the development of human urothelial cancer (UC) and is the 5th most common cancer in men and the 12th most common cancer in women. Muscle invasive urothelial cancer (MIUC) are grouped into basal or luminal molecular subtypes based on their gene expression profile. The basal subtype is more aggressive and can be associated with squamous differentiation, characterized by high expression of keratins (KRT1, 5, 6, 14, and 16) and epidermal growth factor receptor (EGFR) within the tumors. The luminal subtype is less aggressive and is predominately characterized by elevated gene expression of peroxisome proliferator-activated receptor- gamma (PPARγ) and forkhead box protein A1 (FOXA1). We have previously shown that As3+-transformed urothelial cells (As-T) exhibit a basal subtype of UC expressing genes associated with squamous differentiation. We hypothesized that the molecular subtype of the As-T cells could be altered by inducing the expression of PPARγ and/or inhibiting the proliferation of the cells. Non-transformed and As-T cells were treated with Troglitazone (TG, PPARG agonist, 10 µM), PD153035 (PD, an EGFR inhibitor, 1 µM) or a combination of TG and PD for 3 days. The results obtained demonstrate that treatment of the As-T cells with TG upregulated the expression of PPARγ and FOXA1 whereas treatment with PD decreased the expression of some of the basal keratins. However, a combined treatment of TG and PD resulted in a consistent decrease of several proteins associated with the basal subtype of bladder cancers (KRT1, KRT14, KRT16, P63, and TFAP2A). Our data suggests that activation of PPARγ while inhibiting cell proliferation facilitates the regulation of genes involved in maintaining the luminal subtype of UC. In vivo animal studies are needed to address the efficacy of using PPARγ agonists and/or proliferation inhibitors to reduce tumor grade/stage of MIUC.


Assuntos
Arsenitos/farmacologia , Proliferação de Células/efeitos dos fármacos , PPAR gama/metabolismo , Troglitazona/farmacologia , Animais , Biomarcadores Tumorais/metabolismo , Linhagem Celular Tumoral , Regulação para Baixo/efeitos dos fármacos , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/metabolismo , Fator 3-alfa Nuclear de Hepatócito/genética , Fator 3-alfa Nuclear de Hepatócito/metabolismo , Humanos , Queratinas/genética , Queratinas/metabolismo , Camundongos , Camundongos Nus , PPAR gama/agonistas , Quinazolinas/farmacologia , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Transcriptoma/efeitos dos fármacos , Transplante Heterólogo , Regulação para Cima/efeitos dos fármacos , Neoplasias da Bexiga Urinária/metabolismo , Neoplasias da Bexiga Urinária/patologia
8.
EClinicalMedicine ; 19: 100247, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32140668

RESUMO

BACKGROUND: Sudden infant death syndrome (SIDS) is the leading cause of postneonatal mortality. Although the rate has plateaued, any unexpected death of an infant is a family tragedy thus finding causes and contributors to risk remains a major public health concern. The primary objective of this investigation was to determine patterns of drinking and smoking during pregnancy that increase risk of SIDS. METHODS: The Safe Passage Study was a prospective, multi-center, observational study with 10,088 women, 11,892 pregnancies, and 12,029 fetuses, followed to 1-year post delivery. Subjects were from two sites in Cape Town, South Africa and five United States sites, including two American Indian Reservations. Group-based trajectory modeling was utilized to categorize patterns of drinking and smoking exposure during pregnancy. FINDINGS: One-year outcome was ascertained in 94·2% infants, with 28 SIDS (2·43/1000) and 38 known causes of death (3·30/1000). The increase in relative risk for SIDS, adjusted for key demographic and clinical characteristics, was 11·79 (98·3% CI: 2·59-53·7, p < 0·001) in infants whose mothers reported both prenatal drinking and smoking beyond the first trimester, 3.95 (98·3% CI: 0·44-35·83, p = 0·14), for drinking only beyond the first trimester and 4·86 (95% CI: 0·97-24·27, p = 0·02) for smoking only beyond the first trimester as compared to those unexposed or reported quitting early in pregnancy. INTERPRETATION: Infants prenatally exposed to both alcohol and cigarettes continuing beyond the first trimester have a substantially higher risk for SIDS compared to those unexposed, exposed to alcohol or cigarettes alone, or when mother reported quitting early in pregnancy. Given that prenatal drinking and smoking are modifiable risk factors, these results address a major global public health problem. FUNDING: National Institute on Alcohol Abuse and Alcoholism, Eunice Kennedy Shriver National Institute of Child Health and Human Development, and the National Institute on Deafness and Other Communication Disorders.

9.
Forensic Sci Med Pathol ; 16(1): 91-98, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31741206

RESUMO

Understanding case identification practices, protocols, and training needs of medical examiners and coroners (MEC) may inform efforts to improve cause-of-death certification. We surveyed a U.S.-representative sample of MECs and described investigation practices and protocols used in certifying sudden unexpected infant deaths (SUID). We also identified MEC training and resource needs. Of the 377 respondents, use of the SUID Investigation Reporting Form or an equivalent was 89% for large, 87% for medium, and 52% for small jurisdictions. Routine completion of infant medical history, witness interviews, autopsy, photos or videos, and family social history for infant death investigations was ≥80%, but routine scene re-creation with a doll was 30% in small, 64% in medium, and 59% in large offices. Seventy percent of MECs reported infant death investigation training needs. Increased training and use of standardized practices may improve SUID cause-of-death certification, allowing us to better understand SUID.


Assuntos
Médicos Legistas/estatística & dados numéricos , Medicina Legal/estatística & dados numéricos , Morte Súbita do Lactente , Adulto , Idoso , Autopsia/estatística & dados numéricos , Controle de Formulários e Registros/estatística & dados numéricos , Humanos , Lactente , Anamnese/estatística & dados numéricos , Pessoa de Meia-Idade , Avaliação das Necessidades , Fotografação/estatística & dados numéricos , Inquéritos e Questionários , Estados Unidos , Gravação em Vídeo/estatística & dados numéricos , Adulto Jovem
10.
Forensic Sci Med Pathol ; 15(4): 622-628, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31502215

RESUMO

This report details the proceedings and conclusions from the 3rd International Congress on Unexplained Deaths in Infants and Children, held November 26-27, 2018 at the Radcliffe Institute at Harvard University. The Congress was motivated by the increasing rejection of the diagnosis Sudden Infant Death Syndrome (SIDS) in the medical examiner community, leading to falsely depressed reported SIDS rates and undermining the validity and reliability of the diagnosis, which remains a leading cause of infant and child mortality. We describe the diagnostic shift away from SIDS and the practical issues contributing to it. The Congress was attended by major figures and opinion leaders in this area from countries significantly engaged in this problem. Four categories (International Classification of Diseases (ICD)-11 categories of MH11, MH12, MH14, PB00-PB0Z) were recommended for classification, and explicit definitions and guidance were provided for death certifiers. SIDS was reframed as unexplained sudden death in infancy or SIDS/MH11 to emphasize that either term signifies the lack of explanation following a rigorous investigation. A distinct category for children over the age of 1 was recommended (MH12). Definitions and exclusions were provided for the alternative categories of accidental asphyxia and undetermined. As recommended, unexplained sudden death in infancy or SIDS on a death certificate will code a unique, trackable entity, accurately reflecting the inability to determine a definitive explanation, while satisfying surveillance needs and reliable identification for research efforts. The conclusions will be submitted to the World Health Organization for inclusion in the upcoming ICD-11.


Assuntos
Morte Súbita , Morte Súbita do Lactente/classificação , Terminologia como Assunto , Acidentes , Asfixia , Roupas de Cama, Mesa e Banho , Criança , Medicina Legal , Humanos , Lactente , Classificação Internacional de Doenças
11.
Acad Pathol ; 6: 2374289519831930, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30859125

RESUMO

The forensic and autopsy pathology service within the Department of Pathology at University of North Dakota School of Medicine provides an optional, structured autopsy experience for medical students during the second year of the curriculum. This experience reinforces forensic autopsy pathology as the practice of medicine and highlights the American Association of Medical Colleges Core Entrustable Professional Activities. Students self-select for this optional, noncredit autopsy observership. Prior to the experience, interested students participate in a session that reviews the professional and educational expectations of the autopsy experience, autopsy safety training, and logistics of call. Groups of up to 4 students are on call for an autopsy. Student groups observe and participate in an autopsy, ideally from scene through autopsy performance, slide review, and toxicology results. The student groups use a structured presentation format for summarizing their autopsy experience, forming a differential and final diagnosis, completing the death certificate, and discussing quality management or learning issues in the case. At the end of the semester, all students participating in the experience meet and each group presents a 10-minute, structured review of their case. At least 6 core entrustable professional activities were addressed in every autopsy review; some had more when advanced clinical questions or safety issues were identified. Additionally, one student presented his case at a national meeting with a resultant publication. The experience provided (1) a positive introduction to autopsy pathology, (2) reinforced the role of pathology in medicine, and (3) provided concrete examples of American Association of Medical Colleges Core Entrustable Professional Activities within pathology for students in preclinical years.

12.
PLoS One ; 13(12): e0207877, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30550540

RESUMO

Muscle invasive urothelial carcinomas are divided into various molecular subtypes with basal and luminal subtypes being the prominent ones. The basal muscle-invasive urothelial carcinomas are generally more aggressive at presentation and significantly enriched with squamous features. Our laboratory has developed an in-vitro model of urothelial cancer by transforming the immortalized cell line UROtsa with arsenite (As3+) and cadmium (Cd2+). In this study, we characterized the tumors formed by these transformed cell lines as more basal-like based on their gene expression patterns with increased expression of KRT1, KRT5, KRT6, KRT14, KRT16, KRT17 and CD44. In addition, histological examination of these tumor transplants showed squamous features enriched in basal muscle invasive urothelial carcinomas. The expression of these genes increased in the transformed cell lines as well as in the urospheres, which are putative cancer initiating cells/stem cells derived from the cell lines. There was also increased expression of these genes in the urospheres derived from the parent UROtsa cell line. Thus, our data shows that the As3+ and Cd2+-transformed cell lines and their derived tumor transplants have gene expression profiles similar to the basal subtype of muscle invasive bladder carcinomas with tumors having enriched squamous features. The increased expression of basal markers in the urospheres suggests that stem cells may be involved in the development of squamous differentiation seen in some of the muscle invasive bladder carcinomas.


Assuntos
Arsenitos/toxicidade , Cádmio/toxicidade , Neoplasias da Bexiga Urinária/patologia , Urotélio/efeitos dos fármacos , Urotélio/patologia , Animais , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Diferenciação Celular , Linhagem Celular Transformada , Transformação Celular Neoplásica/induzido quimicamente , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/patologia , Xenoenxertos , Humanos , Imuno-Histoquímica , Camundongos , Camundongos Nus , Modelos Biológicos , Invasividade Neoplásica/genética , Invasividade Neoplásica/patologia , Transplante de Neoplasias , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Esferoides Celulares/metabolismo , Esferoides Celulares/patologia , Transcriptoma , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/metabolismo , Urotélio/metabolismo
13.
Acad Pathol ; 4: 2374289517735092, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29057317

RESUMO

This study documents outcomes, including student career choices, of the North Dakota Institutional Development Award Networks of Biomedical Research Excellence program that provides 10-week, summer undergraduate research experiences at the University of North Dakota School of Medicine and Health Sciences. Program evaluation initiated in 2008 and, to date, 335 students have completed the program. Of the 335, 214 students have successfully completed their bachelor's degree, 102 are still undergraduates, and 19 either did not complete a bachelor's degree or were lost to follow-up. The program was able to track 200 of the 214 students for education and career choices following graduation. Of these 200, 76% continued in postgraduate health-related education; 34.0% and 20.5% are enrolled in or have completed MD or PhD programs, respectively. Other postbaccalaureate pursuits included careers in pharmacy, optometry, dentistry, public health, physical therapy, nurse practitioner, and physician's assistant, accounting for an additional 21.5%. Most students electing to stop formal education at the bachelor's degree also entered fields related to health care or science, technology, engineering, and mathematics (19.5%), with only a small number of the 200 students tracked going into service or industries which lacked an association with the health-care workforce (4.5%). These student outcomes support the concept that participation in summer undergraduate research boosts efforts to populate the pipeline of future researchers and health professionals. It is also an indication that future researchers and health professionals will be able to communicate the value of research in their professional and social associations. The report also discusses best practices and issues in summer undergraduate research for students originating from rural environments.

14.
Future Oncol ; 13(21): 1873-1881, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28835109

RESUMO

AIM: We previously reported that incidence rates for chronic lymphocytic leukemia (CLL) among US states are significantly correlated with levels of residential radon (RR). Because these correlations could be influenced by confounding and/or misclassification among large geographic units, we reinvestigated them using smaller geographic units that better reflect exposure and disease at the individual level. METHODS: We examined the relationships between CLL and RR per county in 478 counties with publicly-available data. RESULTS: After adjustment for ultraviolet radiation, a possible risk factor for CLL, county rates for CLL and RR were significantly correlated among males and females both together and separately (p < 0.0001). CONCLUSION: CLL is significantly associated with RR at the county level.


Assuntos
Exposição Ambiental , Leucemia Linfocítica Crônica de Células B/epidemiologia , Leucemia Linfocítica Crônica de Células B/etiologia , Radônio/efeitos adversos , Distribuição por Idade , Feminino , Humanos , Incidência , Masculino , Vigilância da População , Estados Unidos/epidemiologia
15.
Toxicol Appl Pharmacol ; 331: 41-53, 2017 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-28501331

RESUMO

Urothelial cancers have an environmental etiological component, and previous studies from our laboratory have shown that arsenite (As+3) can cause the malignant transformation of the immortalized urothelial cells (UROtsa), leading to the expression of keratin 6 (KRT6). The expression of KRT6 in the parent UROtsa cells can be induced by the addition of epidermal growth factor (EGF). Tumors formed by these transformed cells have focal areas of squamous differentiation that express KRT6. The goal of this study was to investigate the mechanism involved in the upregulation of KRT6 in urothelial cancers and to validate that the As+3-transformed UROtsa cells are a model of urothelial cancer. The results obtained showed that the parent and the As+3-transformed UROtsa cells express EGFR which is phosphorylated with the addition of epidermal growth factor (EGF) resulting in an increased expression of KRT6. Inhibition of the extracellular-signal regulated kinases (ERK1/2) pathway by the addition of the mitogen-activated protein kinase kinase 1 (MEK1) and MEK2 kinase inhibitor U0126 resulted in a decrease in the phosphorylation of ERK1/2 and a reduced expression of KRT6. Immuno-histochemical analysis of the tumors generated by the As+3-transformed isolates expressed EGFR and tumors formed by two of the transformed isolates expressed the phosphorylated form of EGFR. These results show that the expression of KRT6 is regulated at least in part by the ERK1/2 pathway and that the As+3-transformed human urothelial cells have the potential to serve as a valid model to study urothelial carcinomas.


Assuntos
Arsenitos/toxicidade , Queratina-6/biossíntese , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Neoplasias da Bexiga Urinária/metabolismo , Urotélio/efeitos dos fármacos , Urotélio/metabolismo , Animais , Linhagem Celular Transformada , Linhagem Celular Tumoral , Ativação Enzimática/efeitos dos fármacos , Ativação Enzimática/fisiologia , Regulação Neoplásica da Expressão Gênica , Humanos , Queratina-6/genética , Sistema de Sinalização das MAP Quinases/fisiologia , Camundongos , Camundongos Nus , Ensaios Antitumorais Modelo de Xenoenxerto/métodos
16.
Pediatr Dev Pathol ; 20(2): 120-132, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28326963

RESUMO

Objective Describe the classification system for assigning the cause of stillbirth in the Safe Passage Study, an international, multi-institutional, prospective analysis conducted by the NIAAA/NICHD-funded Prenatal Alcohol in SIDS and Stillbirth (PASS) Research Network. The study mission is to determine the role of prenatal alcohol and/or cigarette smoke exposure in adverse pregnancy outcomes, including stillbirth, in a high-risk cohort of 12,000 maternal/fetal dyads. Methods The PASS Network classification system is based upon 5 "sites of origin" for cause of stillbirth, further subdivided into mechanism subcategories; both are employed to assign an ultimate cause of death. Each PASS stillbirth was assigned a cause of death and status of sporadic versus recurrent. Adjudication involved review of maternal and obstetrical records; fetal autopsy and placental findings; and required complete consensus in each case. Two published classification systems, ie, INCODE and ReCoDe, were used for comparison. Results Causes of stillbirth classified were fetal (26%), placental (53%), external (5%), and undetermined (16%). Nine cases (47%) had placental causes of death due to maternal disorders that carry recurrence risks. There was full agreement for cause of death across the 3 classification systems in 26% of cases and partial agreement among them in 42% of cases. Conclusions The proposed PASS schema employs a user-friendly classification that provides comparable information to previously published systems. Advantages include its simplicity, mechanistic formulations, tight clinicopathologic integration, provision for an undetermined category, and its wide applicability to perinatal mortality review boards with access to information routinely collected during clinicopathologic evaluations.


Assuntos
Natimorto , Feminino , Humanos , Gravidez , Estudos Prospectivos , Projetos de Pesquisa , Fatores de Risco
17.
J Forensic Sci ; 61(6): 1508-1514, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27677096

RESUMO

The rate for the sudden infant death syndrome (SIDS) in Cape Town, South Africa, is estimated to be among the highest in the world (3.41/1000 live births). In several of these areas, including those of extreme poverty, only sporadic, nonstandardized infant autopsy, and death scene investigation (DSI) occurred. In this report, we detail a feasibility project comprising 18 autopsied infants with sudden and unexpected death whose causes of death were adjudicated according to the 1991 NICHD definitions (SIDS, n = 7; known cause of death, n = 7; and unclassified, n = 4). We instituted a standardized autopsy and infant DSI through a collaborative effort of local forensic pathology officers and clinical providers. The high standard of forensic investigation met international standards, identified preventable disease, and allowed for incorporation of research. We conclude that an effective infant autopsy and DSI protocol can be established in areas with both high sudden unexpected infant death, and elsewhere. (SUID)/SIDS risk and infrastructure challenges.


Assuntos
Autopsia , Patologia Legal , Morte Súbita do Lactente , Humanos , Lactente , Meio Social , África do Sul
18.
J Neuropathol Exp Neurol ; 75(11): 1048-1057, 2016 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-27634962

RESUMO

The Safe Passage Study is an international, prospective study of approximately 12 000 pregnancies to determine the effects of prenatal alcohol exposure (PAE) upon stillbirth and the sudden infant death syndrome (SIDS). A key objective of the study is to elucidate adverse effects of PAE upon binding to serotonin (5-HT) 1A receptors in brainstem homeostatic networks postulated to be abnormal in unexplained stillbirth and/or SIDS. We undertook a feasibility assessment of 5-HT1A receptor binding using autoradiography in the medulla oblongata (6 nuclei in 27 cases). 5-HT1A binding was compared to a reference dataset from the San Diego medical examiner's system. There was no adverse effect of postmortem interval ≤100 h. The distribution and quantitated values of 5-HT1A binding in Safe Passage Study cases were essentially identical to those in the reference dataset, and virtually identical between stillbirths and live born fetal cases in grossly non-macerated tissues. The pattern of binding was present at mid-gestation with dramatic changes in binding levels in the medullary 5-HT nuclei over the second half of gestation; there was a plateau at lower levels in the neonatal period and into infancy. This study demonstrates feasibility of 5-HT1A binding analysis in the medulla in the Safe Passage Study.

19.
Pediatrics ; 137(1)2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26634772

RESUMO

BACKGROUND: Reductions in sudden infant death syndrome (SIDS) are commonly attributed to modifications in infant sleep environments. Approaches to diagnosis in sudden infant death, death scene investigations, the prevalence of intrinsic risk factors for SIDS, and the potential influence of treatment-related factors on infant vulnerability have also changed. Understanding all contributory factors may help reduce residual SIDS rates. METHODS: We analyzed US Mortality Multiple Causes Records for 1983 to 2012 to compare SIDS postneonatal mortality rates with a projection applying non-SIDS mortality changes, using those changes as a proxy measure for alterations in intrinsic risk. Composites of neglect-related, unknown, and circumstantial respiratory diagnoses were measured, as was a cumulative composite of unexplained infant death diagnoses. Cluster analysis with leading causes of postneonatal mortality and SIDS mortality rates for low birth weight infants were also examined. RESULTS: SIDS and non-SIDS postneonatal mortality rates were concordant over time. Important variance was seen 1994 to 1996, coinciding with Back-to-Sleep initiation. Other variance, eliminated in the cumulative composite, appeared related to differences in diagnostic practices. Changes in SIDS rates resembled changes in mortality from congenital malformations, respiratory distress of the newborn, and diseases of the circulatory system. SIDS rates for low birth weight infants followed broader postneonatal trends. CONCLUSIONS: SIDS mortality followed trends in overall postneonatal mortality, including effects of changes in the infant sleep environment and diagnostic classification. Preventing asphyxia risk in the sleep environment must be coupled with efforts to understand intrinsic biological pathways, some potentially associated with other categories of infant and perinatal mortality.


Assuntos
Mortalidade Infantil , Morte Súbita do Lactente/epidemiologia , Causas de Morte , Feminino , Humanos , Lactente , Mortalidade Infantil/tendências , Recém-Nascido , Masculino
20.
PLoS One ; 10(3): e0120132, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25803827

RESUMO

BACKGROUND: Cultures of human proximal tubule cells have been widely utilized to study the role of EMT in renal disease. The goal of this study was to define the role of growth media composition on classic EMT responses, define the expression of E- and N-cadherin, and define the functional epitope of MT-3 that mediates MET in HK-2 cells. METHODS: Immunohistochemistry, microdissection, real-time PCR, western blotting, and ELISA were used to define the expression of E- and N-cadherin mRNA and protein in HK-2 and HPT cell cultures. Site-directed mutagenesis, stable transfection, measurement of transepithelial resistance and dome formation were used to define the unique amino acid sequence of MT-3 associated with MET in HK-2 cells. RESULTS: It was shown that both E- and N-cadherin mRNA and protein are expressed in the human renal proximal tubule. It was shown, based on the pattern of cadherin expression, connexin expression, vectorial active transport, and transepithelial resistance, that the HK-2 cell line has already undergone many of the early features associated with EMT. It was shown that the unique, six amino acid, C-terminal sequence of MT-3 is required for MT-3 to induce MET in HK-2 cells. CONCLUSIONS: The results show that the HK-2 cell line can be an effective model to study later stages in the conversion of the renal epithelial cell to a mesenchymal cell. The HK-2 cell line, transfected with MT-3, may be an effective model to study the process of MET. The study implicates the unique C-terminal sequence of MT-3 in the conversion of HK-2 cells to display an enhanced epithelial phenotype.


Assuntos
Caderinas/genética , Transição Epitelial-Mesenquimal , Túbulos Renais Proximais/citologia , Proteínas do Tecido Nervoso/metabolismo , Transporte Biológico Ativo , Caderinas/análise , Linhagem Celular , Expressão Gênica , Humanos , Túbulos Renais Proximais/metabolismo , Túbulos Renais Proximais/ultraestrutura , Metalotioneína 3 , Proteínas do Tecido Nervoso/análise , Proteínas do Tecido Nervoso/química , Isoformas de Proteínas/análise , Isoformas de Proteínas/metabolismo , Estrutura Terciária de Proteína , RNA Mensageiro/análise , RNA Mensageiro/genética
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