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1.
PLoS One ; 19(1): e0282769, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38265977

RESUMO

Targeted therapies have increased cancer therapy-related diarrhea (CTD) burden, with high incidence and/or severity of diarrhea for some agents that inhibit epidermal growth factor receptor and receptor tyrosine kinases. Neratinib is a pan-HER tyrosine kinase inhibitor approved for breast cancer treatment and causes severe diarrhea in >95% of patients. Crofelemer, a novel intestinal chloride ion channel modulator, is an approved antidiarrheal drug for symptomatic relief of noninfectious diarrhea in patients with HIV/AIDS receiving antiretroviral therapy. The objective of this study was to evaluate the effectiveness of crofelemer prophylaxis in reducing the incidence /severity of neratinib-induced diarrhea without concomitant administration of loperamide in female beagle dogs. A pilot study using 3 dogs determined a maximum daily tolerated dose of neratinib was between 40 and 80 mg; this dose would induce a consistent incidence/severity of diarrhea without risking severe dehydration. In the definitive study, 24 female beagle dogs (8/group) received neratinib once daily and placebo capsules (CTR) four times/day, or neratinib once daily and crofelemer 125 mg delayed-release tablets given two times (BID), or neratinib once daily and crofelemer 125 mg delayed-release tablets given four times per day (QID). Fecal scores were collected twice daily using an established canine stool scoring scale called the Purina Fecal Scoring (PFS) System. After 28 days, using analysis of covariance (ANCOVA), dogs in the CTR group had a significantly higher average number of weekly loose/watery stools (PFS of 6 or 7) when compared to either crofelemer BID (8.71±2.2 vs. 5.96±2.2, p = 0.028) or crofelemer QID (8.70±2.2 vs. 5.74±2.2, p = 0.022) treatment groups. The average number of weekly loose/watery stools were not different between the crofelemer BID and QID treatment groups (p = 0.84). This study showed that crofelemer prophylaxis reduced the incidence/severity of neratinib-associated diarrhea in female beagle dogs without the need for any loperamide administration.


Assuntos
Diarreia , Loperamida , Proantocianidinas , Quinolinas , Humanos , Feminino , Animais , Cães , Incidência , Projetos Piloto , Diarreia/induzido quimicamente , Diarreia/tratamento farmacológico , Diarreia/veterinária
2.
Environ Sci Pollut Res Int ; 30(14): 40952-40960, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36626052

RESUMO

The François' langur (Trachypithecus francoisi) is an endangered primate living in limestone forests in Vietnam and China. From October 2017 to August 2018, the habitat preferences and the range of the Francois' langur were surveyed in the Mayanghe Nature Reserve, Guizhou, People's Republic of China. To estimate the range and predict suitable habitat of François' langur, a Gaussian normal kernel density estimation and species distribution models (BIOMOD2) were used along with data on environmental variables and records of the langur's occurrence. The total range of François' langur in the reserve is 68.76 km2, accounting for 22.1% of the total area of the reserve. The elevation of the main utilisation area is 500-800 m, accounting for 48.53% of the total area of the reserve. The maximum slope utilised is 20°-30°, 30.19 km2 and accounting for 30.56% of the total area. The habitat used is largely distributed along valleys, preferred broad leaf forest, lower elevation, and close to rivers. Broad leaf forest is the main habitat type utilised, totalling 25.57 km2 and accounting for 37.19% of the total area. Our models predicted that the suitable habitat in the reserve is 62.46 km2, accounting for 20.08% of the total reserve area, with 32.93-km2 suitable habitat occurring in the core zone, 22.44 km2 in the buffer zone, and 7.02 km2 in the experimental zone. Our results indicate that only limited suitable habitat (51%) adverse reserve zoning exists in the Mayanghe Nature Reserve of François' langur.


Assuntos
Colobinae , Animais , Ecossistema , Florestas , China
3.
ACS Omega ; 7(16): 13667-13675, 2022 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-35559166

RESUMO

Posttranscriptional tRNA modifications are essential for proper gene expression, and defects in the enzymes that perform tRNA modifications are associated with numerous human disorders. Throughout eukaryotes, 2'-O-methylation of residues 32 and 34 of the anticodon loop of tRNA is important for proper translation, and in humans, a lack of these modifications results in non-syndromic X-linked intellectual disability. In yeast, the methyltransferase Trm7 forms a complex with Trm732 to 2'-O-methylate tRNA residue 32 and with Trm734 to 2'-O-methylate tRNA residue 34. Trm732 and Trm734 are required for the methylation activity of Trm7, but the role of these auxiliary proteins is not clear. Additionally, Trm732 and Trm734 homologs are implicated in biological processes not directly related to translation, suggesting that these proteins may have additional cellular functions. To identify critical amino acids in Trm732, we generated variants and tested their ability to function in yeast cells. We identified a conserved RRSAGLP motif in the conserved DUF2428 domain of Trm732 that is required for tRNA modification activity by both yeast Trm732 and its human homolog, THADA. The identification of Trm732 variants that lack tRNA modification activity will help to determine if other biological functions ascribed to Trm732 and THADA are directly due to tRNA modification or to secondary effects due to other functions of these proteins.

4.
PLoS One ; 15(11): e0242737, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33253256

RESUMO

Posttranscriptional modification of tRNA is critical for efficient protein translation and proper cell growth, and defects in tRNA modifications are often associated with human disease. Although most of the enzymes required for eukaryotic tRNA modifications are known, many of these enzymes have not been identified and characterized in several model multicellular eukaryotes. Here, we present two related approaches to identify the genes required for tRNA modifications in multicellular organisms using primer extension assays with fluorescent oligonucleotides. To demonstrate the utility of these approaches we first use expression of exogenous genes in yeast to experimentally identify two TRM1 orthologs capable of forming N2,N2-dimethylguanosine (m2,2G) on residue 26 of cytosolic tRNA in the model plant Arabidopsis thaliana. We also show that a predicted catalytic aspartate residue is required for function in each of the proteins. We next use RNA interference in cultured Drosophila melanogaster cells to identify the gene required for m2,2G26 formation on cytosolic tRNA. Additionally, using these approaches we experimentally identify D. melanogaster gene CG10050 as the corresponding ortholog of human DTWD2, which encodes the protein required for formation of 3-amino-3-propylcarboxyuridine (acp3U) on residue 20a of cytosolic tRNA. We further show that A. thaliana gene AT2G41750 can form acp3U20b on an A. thaliana tRNA expressed in yeast cells, and that the aspartate and tryptophan residues in the DXTW motif of this protein are required for modification activity. These results demonstrate that these approaches can be used to study tRNA modification enzymes.


Assuntos
Proteínas de Arabidopsis , Citosol/enzimologia , Proteínas de Drosophila , RNA de Transferência , tRNA Metiltransferases , Animais , Arabidopsis/enzimologia , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster , RNA de Transferência/genética , RNA de Transferência/metabolismo , tRNA Metiltransferases/genética , tRNA Metiltransferases/metabolismo
5.
PLoS Genet ; 14(3): e1007288, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29596413

RESUMO

Modification defects in the tRNA anticodon loop often impair yeast growth and cause human disease. In the budding yeast Saccharomyces cerevisiae and the phylogenetically distant fission yeast Schizosaccharomyces pombe, trm7Δ mutants grow poorly due to lack of 2'-O-methylation of C32 and G34 in the tRNAPhe anticodon loop, and lesions in the human TRM7 homolog FTSJ1 cause non-syndromic X-linked intellectual disability (NSXLID). However, it is unclear why trm7Δ mutants grow poorly. We show here that despite the fact that S. cerevisiae trm7Δ mutants had no detectable tRNAPhe charging defect in rich media, the cells constitutively activated a robust general amino acid control (GAAC) response, acting through Gcn2, which senses uncharged tRNA. Consistent with reduced available charged tRNAPhe, the trm7Δ growth defect was suppressed by spontaneous mutations in phenylalanyl-tRNA synthetase (PheRS) or in the pol III negative regulator MAF1, and by overexpression of tRNAPhe, PheRS, or EF-1A; all of these also reduced GAAC activation. Genetic analysis also demonstrated that the trm7Δ growth defect was due to the constitutive robust GAAC activation as well as to the reduced available charged tRNAPhe. Robust GAAC activation was not observed with several other anticodon loop modification mutants. Analysis of S. pombe trm7 mutants led to similar observations. S. pombe Trm7 depletion also resulted in no observable tRNAPhe charging defect and a robust GAAC response, and suppressors mapped to PheRS and reduced GAAC activation. We speculate that GAAC activation is widely conserved in trm7 mutants in eukaryotes, including metazoans, and might play a role in FTSJ1-mediated NSXLID.


Assuntos
Aminoácidos/metabolismo , Anticódon , RNA de Transferência/metabolismo , Saccharomyces cerevisiae/classificação , Saccharomyces cerevisiae/genética , Schizosaccharomyces/classificação , Schizosaccharomyces/genética , Genes Fúngicos , Metilação , Mutação , Filogenia , Saccharomyces cerevisiae/crescimento & desenvolvimento , Schizosaccharomyces/crescimento & desenvolvimento
6.
RNA ; 24(3): 410-422, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29259051

RESUMO

Microorganisms have universally adapted their RNAs and proteins to survive at a broad range of temperatures and growth conditions. However, for RNAs, there is little quantitative understanding of the effects of mutations on function at high temperatures. To understand how variant tRNA function is affected by temperature change, we used the tRNA nonsense suppressor SUP4oc of the yeast Saccharomyces cerevisiae to perform a high-throughput quantitative screen of tRNA function at two different growth temperatures. This screen yielded comparative values for 9243 single and double variants. Surprisingly, despite the ability of S. cerevisiae to grow at temperatures as low as 15°C and as high as 39°C, the vast majority of variants that could be scored lost half or more of their function when evaluated at 37°C relative to 28°C. Moreover, temperature sensitivity of a tRNA variant was highly associated with its susceptibility to the rapid tRNA decay (RTD) pathway, implying that RTD is responsible for most of the loss of function of variants at higher temperature. Furthermore, RTD may also operate in a met22Δ strain, which was previously thought to fully inhibit RTD. Consistent with RTD acting to degrade destabilized tRNAs, the stability of a tRNA molecule can be used to predict temperature sensitivity with high confidence. These findings offer a new perspective on the stability of tRNA molecules and their quality control at high temperature.


Assuntos
Fatores de Terminação de Peptídeos/genética , Estabilidade de RNA/genética , RNA de Transferência/genética , Proteínas de Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/genética , Biblioteca Gênica , Genes Reporter , Mutação , RNA de Transferência/química , Saccharomyces cerevisiae/fisiologia , Análise de Sequência de DNA , Temperatura
7.
Ann Surg Oncol ; 23(11): 3744-3748, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27172774

RESUMO

OBJECTIVE: This study was designed to examine the impact of patient socioeconomic, clinical, and hospital characteristics on the utilization of robotics in the surgical staging of endometrial cancer. METHODS: Patients surgically treated for endometrial cancer at facilities that offered robotic and open approaches were identified from the National Inpatient Sample Database from 2008 to 2012. The groups were compared for socioeconomic, clinical, and hospital differences. Medical comorbidity scores were calculated using the Charlson comorbidity index. T tests and χ (2) were used to compare groups. Multivariable analyses were used to determine factors that were independently associated with a robotic approach. RESULTS: A total of 18,284 patients were included (robotic, n = 7169; laparotomy, n = 11,115). Significant differences were noted in all patient clinical and socioeconomic characteristics and all hospital characteristics. Multivariable analyses identified factors that independently predicted patients undergoing robotic surgery. These patients were older [adjusted odds ratio (aOR) 1.008; 95 % confidence interval (CI) 1.004-1.011], white (aOR 1.38; 95 % CI 1.27-1.50), and privately insured (aOR 1.16; 95 % CI 1.07-1.26). Clinically, these women were more likely to be obese (aOR 1.20; 95 % CI 1.11-1.30) and to be undergoing an elective case (aOR 1.25; 95 % CI 1.11-1.40). Hospitals were more likely to be under private control (aOR 1.55, 95 % CI 1.39-1.71) but less likely to be located in the south (aOR 0.87; 0.81-0.93), quantified as large or medium (aOR 0.57; 95 %CI 0.50-0.67), or teaching hospitals (aOR 0.68; 95 % CI 0.63-0.74). CONCLUSIONS: Socioeconomic status and hospital characteristics are factors that independently predict robotic utilization in the United States. These racial, socioeconomic, and geographic disparities warrant further study regarding the utilization of this important technology.


Assuntos
Neoplasias do Endométrio/cirurgia , Procedimentos Cirúrgicos Robóticos/estatística & dados numéricos , Fatores Etários , Idoso , Comorbidade , Procedimentos Cirúrgicos Eletivos/estatística & dados numéricos , Neoplasias do Endométrio/complicações , Feminino , Tamanho das Instituições de Saúde/estatística & dados numéricos , Hospitais Privados/estatística & dados numéricos , Hospitais de Ensino , Humanos , Renda , Seguro Saúde/estatística & dados numéricos , Pessoa de Meia-Idade , Obesidade/complicações , População Rural/estatística & dados numéricos , Estados Unidos , População Urbana/estatística & dados numéricos , População Branca/estatística & dados numéricos
8.
Infect Dis Obstet Gynecol ; 2016: 2649708, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27199534

RESUMO

Objective. Gelatin-thrombin matrix (GTM) tissue sealant use was previously identified as an independent predictor of pelvic infection following hysterectomies. We aim to elucidate contributing factors by assessing influence of GTM on bacterial colony formation and characterizing bacteria present at the vaginal cuff. Methods. Escherichia coli was incubated in phosphate-buffered saline (PBS) and pelvic washings with and without GTM to assess influence on colony formation. Pelvic washings of the vaginal cuff were collected from hysterectomies occurring from June through October 2015. In vitro techniques, 16S rRNA gene qPCR, and 16S amplicon sequencing were performed with washings to characterize bacteria at the vaginal cuff. Results. Mean bacterial colony formation in PBS was greater for E. coli incubated in the presence of GTM (1.48 × 10(7) CFU/mL) versus without (9.95 × 10(5) CFU/mL) following 20-hour incubation (p = 0.001). Out of 61 pelvic washings samples, 3 were culture positive (≥5000 CFU/mL) with Enterococcus faecalis. Conclusion. In vitro experiments support a facilitating role of GTM on colony formation of E. coli in PBS. However, given the negative results of surgical site washings following adequate disinfection, the role of GTM in promoting posthysterectomy pelvic infections may be limited. Analysis of pelvic washings revealed presence of E. faecalis, but results were inconclusive. Further studies are recommended.


Assuntos
Gelatina , Histerectomia/efeitos adversos , Infecção Pélvica/etiologia , Infecção Pélvica/prevenção & controle , Trombina , Adesivos Teciduais/efeitos adversos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Contagem de Colônia Microbiana , Escherichia coli/isolamento & purificação , Feminino , Hemostasia Cirúrgica/efeitos adversos , Hemostasia Cirúrgica/métodos , Humanos , Pessoa de Meia-Idade , Infecção Pélvica/microbiologia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/microbiologia , Complicações Pós-Operatórias/prevenção & controle , Fatores de Risco , Vagina/microbiologia , Adulto Jovem
9.
Gynecol Oncol ; 140(3): 518-26, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26731726

RESUMO

OBJECTIVES: Endometrial cancer is a hormonally responsive malignancy. Response to progestins is associated with estrogen receptor (ER) and progesterone receptor (PR) status. CD133 is a marker of endometrial cancer stem cells. We postulated that CD133+ cells express ER and PR and that progestin therapy differentially regulates CD133+ cells. METHODS: The Ishikawa (ER/PR positive) and KLE (ER/PR negative) cell lines were examined for the presence of CD133 populations. Cell lines were treated with 30.4µM medroxyprogesterone 17-acetate (MPA) for 6days. After treatment, cell counts, apoptosis assays and CD133+ populations were examined. In a clinical project, we identified 12 endometrial cancer patients who were treated with progestin drugs at our institution. Using immunohistochemistry, CD133, ER, PR, and androgen receptor (AR) expression was scored and evaluated for change over time on serial biopsies. RESULTS: CD133+ populations were identified in Ishikawa and KLE cell lines. MPA treatment resulted in a significant reduction in the percentage of live cells (Ishikawa, P=0.036; KLE, P=0.0002), significant increase in apoptosis (Ishikawa, P=0.01; KLE, P=0.0006) and significant decrease in CD133+ populations (Ishikawa, P<0.0001; KLE, P=0.0001). ER, PR, AR and CD133 were present in 96.4%, 96.4%, 89.3% and 100% of patient samples respectively. Paralleling the in vitro results, CD133 expression decreased in patients who had histologic response to progestin treatment. CONCLUSION: CD133+ populations decreased after treatment with MPA in an in vitro model and in patients responding to treatment with progestins. Progestin treatment differentially decreases CD133+ cells.


Assuntos
Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/metabolismo , Antígenos CD , Antineoplásicos Hormonais/farmacologia , Neoplasias do Endométrio/tratamento farmacológico , Neoplasias do Endométrio/metabolismo , Glicoproteínas , Acetato de Medroxiprogesterona/farmacologia , Células-Tronco Neoplásicas/efeitos dos fármacos , Peptídeos , Antígeno AC133 , Adulto , Idoso , Antígenos CD/metabolismo , Antineoplásicos Hormonais/uso terapêutico , Apoptose/efeitos dos fármacos , Contagem de Células , Linhagem Celular Tumoral , Feminino , Glicoproteínas/metabolismo , Humanos , Acetato de Medroxiprogesterona/uso terapêutico , Pessoa de Meia-Idade , Células-Tronco Neoplásicas/metabolismo , Peptídeos/metabolismo , Receptores Androgênicos/metabolismo , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo
10.
Am J Obstet Gynecol ; 214(3): 350.e1-350.e10, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26433173

RESUMO

BACKGROUND: Older patients are at increased risk of perioperative morbidity and mortality. There are limited data on the safety of a robotic approach in the staging for endometrial cancer. OBJECTIVE: We compared outcomes in women undergoing laparotomy or robotic surgical staging for endometrial cancer. STUDY DESIGN: Using the Healthcare Cost and Utilization Project National Inpatient Sample database from 2008 through 2010, we abstracted records for patients who had surgery for endometrial cancer with either a robotic approach or laparotomy. Patients were categorized by age (<65 vs ≥65 years and 5-year increments). Medical comorbidity scores were calculated using the Charlson Comorbidity Index. Outcomes included intraoperative/perioperative/medical complications, death, length of stay (LOS), and discharge disposition. Student t and χ(2) tests were used to compare groups and approach. Multiple analysis of variance models were used to compare differences between robotics and laparotomy and age groups. RESULTS: We identified 16,980 patients who had surgery for endometrial cancer with either a robotic approach (age ≥65 years, n = 1228; age <65 years, n = 1574) or laparotomy (age ≥65 years, n = 5914; age <65 years, n = 8264). Older patients had a higher Charlson Comorbidity Index score at the time of surgery (2.6 vs 2.5, P < .001). In laparotomy cases, intraoperative complication rates were similar (4.1% vs 3.7%, P = .17). Older patients had higher rates of perioperative surgical (20.5% vs 15.4%, P < .001) and medical (23.3% vs 15.5%, P < .001) complications, longer LOS (5.1 vs 4.2 days, P < .001), and lower rates of discharge to home (71.2% vs 90.1%, P < .001). In robotic cases, rates of intraoperative complications were similar (5.9% vs 6.8%, P = .32). Older patients had higher rates of perioperative surgical (8.3% vs 5.2%, P = .001) and medical (12.3% vs 6.7%, P = .001) complications, longer LOS (2.00 vs 1.67 days, P < .001), and lower rates of discharge to home (88.8% vs 96.8%, P < .001). With both approaches, as age increased, perioperative surgical and medical complications also increased in a linear fashion. In a subanalysis of older patients (n = 7142), there were lower rates of perioperative surgical (8.3% vs 20.5%, P < .001) and medical (12.3% vs 23.3%, P < .001) complications, death (0.0% vs 0.8%, P < .001), shorter LOS (2.00 vs 5.13 days, P < .001) and higher rate of discharge to home (88.8% vs 71.2%, P < .001) in robotic compared to laparotomy cases. CONCLUSION: Although the risks of surgery increase with age, in patients age ≥65 years, a robotic approach for endometrial cancer appears to be safe given current selection criteria utilized in the United States.


Assuntos
Neoplasias do Endométrio/cirurgia , Laparotomia , Procedimentos Cirúrgicos Robóticos , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Bases de Dados Factuais , Neoplasias do Endométrio/mortalidade , Neoplasias do Endométrio/patologia , Feminino , Humanos , Complicações Intraoperatórias/epidemiologia , Complicações Intraoperatórias/etiologia , Tempo de Internação/estatística & dados numéricos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Resultado do Tratamento
11.
Ann Surg Oncol ; 23(3): 968-74, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26542594

RESUMO

BACKGROUND: This study sought to determine the association between preoperative chemotherapy and postoperative morbidity and mortality in ovarian cancer patients. METHODS: The American College of Surgeons National Surgical Quality Improvement Program was used to identify women who underwent surgery for ovarian cancer between 2005 and 2012. The women were divided into two groups based on whether they had received chemotherapy within 30 days before surgery or not. Preoperative variables, intraoperative measures, and postoperative morbidity and mortality were compared using χ(2) and Student's t test. Multivariable analyses using logistic regression modeling were used to correct for potential confounding variables. RESULTS: Of 1807 patients, 1612 (89.2%) underwent primary surgery, and 195 (10.8%) received preoperative chemotherapy. The chemotherapy group had a lower preoperative platelet count (317,640 vs 249,740 plt/µL; P < 0.001), hematocrit (36.9 vs 33.1%; P < 0.001), and white blood cell (WBC) count (7970 vs 6060 WBC/µL; P < 0.001). Postoperatively, the chemotherapy group had a higher rate of organ/space infection (2.2 vs 4.6%; P = 0.04; odds ratio [OR], 2.12; 95% confidence interval [CI], 1.01-4.47) and a higher blood transfusion rate (17.1 vs 32.3%; P < 0.001; OR, 2.31; 95% CI, 1.67-3.20). A subanalysis of only those with disseminated cancer showed myelosuppression and an increased blood transfusion rate in the chemotherapy group. In multivariable analyses, preoperative chemotherapy, hematocrit, and ascites were independent predictors of postoperative blood transfusion in the entire cohort, whereas preoperative chemotherapy was the only independent predictor of postoperative blood transfusion in the disseminated cancer group. CONCLUSIONS: Preoperative chemotherapy for the treatment of ovarian cancer is associated with myelosuppression and an increased risk of postoperative blood transfusion.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/cirurgia , Ovariectomia , Complicações Pós-Operatórias , Terapia Combinada , Feminino , Seguimentos , Humanos , Tempo de Internação , Pessoa de Meia-Idade , Morbidade , Invasividade Neoplásica , Estadiamento de Neoplasias , Neoplasias Ovarianas/patologia , Cuidados Pré-Operatórios , Prognóstico , Melhoria de Qualidade , Medição de Risco
12.
Genome Biol ; 16: 210, 2015 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-26416026

RESUMO

BACKGROUND: Primordial dwarfism is a state of extreme prenatal and postnatal growth deficiency, and is characterized by marked clinical and genetic heterogeneity. RESULTS: Two presumably unrelated consanguineous families presented with an apparently novel form of primordial dwarfism in which severe growth deficiency is accompanied by distinct facial dysmorphism, brain malformation (microcephaly, agenesis of corpus callosum, and simplified gyration), and severe encephalopathy with seizures. Combined autozygome/exome analysis revealed a novel missense mutation in WDR4 as the likely causal variant. WDR4 is the human ortholog of the yeast Trm82, an essential component of the Trm8/Trm82 holoenzyme that effects a highly conserved and specific (m(7)G46) methylation of tRNA. The human mutation and the corresponding yeast mutation result in a significant reduction of m(7)G46 methylation of specific tRNA species, which provides a potential mechanism for primordial dwarfism associated with this lesion, since reduced m(7)G46 modification causes a growth deficiency phenotype in yeast. CONCLUSION: Our study expands the number of biological pathways underlying primordial dwarfism and adds to a growing list of human diseases linked to abnormal tRNA modification.


Assuntos
Nanismo/genética , Proteínas de Ligação ao GTP/genética , Microcefalia/genética , RNA de Transferência/genética , Nanismo/etiologia , Exoma/genética , Facies , Humanos , Metilação , Microcefalia/etiologia , Mutação de Sentido Incorreto , Saccharomyces cerevisiae/genética
13.
Obstet Gynecol ; 126(3): 559-568, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26244537

RESUMO

OBJECTIVE: To evaluate the perceptions of fellowship program directors of incoming clinical fellows for subspecialty training. METHODS: A validated survey by the American College of Surgeons was modified and distributed to all fellowship program directors in four subspecialties within obstetrics and gynecology: female pelvic medicine and reconstructive surgery, gynecologic oncology, maternal-fetal medicine, and reproductive endocrinology-infertility. The 59-item survey explored five domains concerning preparedness for fellowship: professionalism, independent practice, psychomotor ability, clinical evaluation, and academic scholarship. A Likert scale with five responses was used and tailored to each subspecialty. Standard statistical methods were used to compare responses between subspecialties and to analyze data within each subspecialty individually. RESULTS: One hundred thirty directors completed the survey, for a response rate of 60%. In the domain of professionalism, more than 88% of participants stated that incoming fellows had appropriate interactions with faculty and staff. Scores in this domain were lower for gynecologic oncology respondents (P=.046). Responses concerning independent practice of surgical procedures (hysterectomy, pelvic reconstruction, and minimally invasive) were overwhelmingly negative. Only 20% of first-year fellows were able to independently perform a vaginal hysterectomy, 46% an abdominal hysterectomy, and 34% basic hysteroscopic procedures. Appropriate postoperative care (63%) and management of the critically ill patient (71%) were rated adequate for all subspecialties. CONCLUSION: Graduating residents may be underprepared for advanced subspecialty training, necessitating an evaluation of the current structure of resident and fellow curriculum. LEVEL OF EVIDENCE: III.


Assuntos
Competência Clínica , Educação de Pós-Graduação em Medicina/organização & administração , Bolsas de Estudo/organização & administração , Internato e Residência/organização & administração , Adulto , Estudos Transversais , Feminino , Ginecologia/educação , Humanos , Masculino , Determinação de Necessidades de Cuidados de Saúde , Obstetrícia/educação , Avaliação de Programas e Projetos de Saúde , Estados Unidos
14.
Methods Enzymol ; 560: 1-17, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26253963

RESUMO

The rapid tRNA decay (RTD) pathway is a tRNA quality control pathway known to degrade several specific hypomodified or destabilized tRNAs in the yeast Saccharomyces cerevisiae. In this chapter, we describe seven methods for identifying RTD substrates, with a focus on two new approaches: a high-throughput approach that utilizes a suppressor tRNA library, fluorescence-activated cell sorting, and deep sequencing, and has greatly expanded the known range of RTD substrates; and a poison primer extension assay that allows for the measurement of levels of suppressor tRNA variants, even in the presence of highly similar endogenous tRNAs. We also discuss different applications of the use of the high-throughput and poison primer extension methodologies for different problems in tRNA biology.


Assuntos
Ensaios de Triagem em Larga Escala/métodos , Estabilidade de RNA/genética , RNA de Transferência/genética , Citometria de Fluxo/métodos , RNA de Transferência/metabolismo , Saccharomyces cerevisiae
15.
Hum Mutat ; 36(12): 1176-87, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26310293

RESUMO

tRNA modifications are crucial for efficient and accurate protein synthesis, and modification defects are frequently associated with disease. Yeast trm7Δ mutants grow poorly due to lack of 2'-O-methylated C32 (Cm32 ) and Gm34 on tRNA(Phe) , catalyzed by Trm7-Trm732 and Trm7-Trm734, respectively, which in turn results in loss of wybutosine at G37 . Mutations in human FTSJ1, the likely TRM7 homolog, cause nonsyndromic X-linked intellectual disability (NSXLID), but the role of FTSJ1 in tRNA modification is unknown. Here, we report that tRNA(Phe) from two genetically independent cell lines of NSXLID patients with loss-of-function FTSJ1 mutations nearly completely lacks Cm32 and Gm34 , and has reduced peroxywybutosine (o2yW37 ). Additionally, tRNA(Phe) from an NSXLID patient with a novel FTSJ1-p.A26P missense allele specifically lacks Gm34 , but has normal levels of Cm32 and o2yW37 . tRNA(Phe) from the corresponding Saccharomyces cerevisiae trm7-A26P mutant also specifically lacks Gm34 , and the reduced Gm34 is not due to weaker Trm734 binding. These results directly link defective 2'-O-methylation of the tRNA anticodon loop to FTSJ1 mutations, suggest that the modification defects cause NSXLID, and may implicate Gm34 of tRNA(Phe) as the critical modification. These results also underscore the widespread conservation of the circuitry for Trm7-dependent anticodon loop modification of eukaryotic tRNA(Phe) .


Assuntos
Anticódon , Retardo Mental Ligado ao Cromossomo X/genética , Metiltransferases/genética , Mutação , Proteínas Nucleares/genética , RNA de Transferência/genética , Alelos , Sequência de Aminoácidos , Substituição de Aminoácidos , Linhagem Celular , Códon , Feminino , Expressão Gênica , Genótipo , Humanos , Masculino , Retardo Mental Ligado ao Cromossomo X/diagnóstico , Metilação , Metiltransferases/química , Modelos Moleculares , Proteínas Nucleares/química , Conformação de Ácido Nucleico , Linhagem , Conformação Proteica , RNA de Transferência/química , RNA de Transferência/metabolismo , RNA de Transferência de Fenilalanina/genética , RNA de Transferência de Fenilalanina/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo
16.
Philos Trans R Soc Lond B Biol Sci ; 370(1673)2015 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-26056371

RESUMO

The Golden Retriever Lifetime Study (GRLS) is the first prospective longitudinal study attempted in veterinary medicine to identify the major dietary, genetic and environmental risk factors for cancer and other important diseases in dogs. The GRLS is an observational study that will follow a cohort of 3000 purebred Golden Retrievers throughout their lives via annual online questionnaires from the dog owner and annual physical examinations and collection of biological samples by the primary care veterinarian. The field of comparative medicine investigating naturally occurring disorders in pets is specifically relevant to the many diseases that have a genetic basis for disease in both animals and humans, including cancer, blindness, metabolic and behavioural disorders and some neurodegenerative disorders. The opportunity for the GRLS to provide high-quality data for translational comparative medical initiatives in several disease categories is great. In particular, the opportunity to develop a lifetime dataset of lifestyle and activity, environmental exposure and diet history combined with simultaneous annual biological sample sets and detailed health outcomes will provide disease incidence data for this cohort of geographically dispersed dogs and associations with a wide variety of potential risk factors. The GRLS will provide a lifetime historical context, repeated biological sample sets and outcomes necessary to interrogate complex associations between genes and environmental influences and cancer.


Assuntos
Doenças do Cão/etiologia , Cães , Neoplasias/veterinária , Animais , Estudos de Coortes , Dieta/efeitos adversos , Dieta/veterinária , Exposição Ambiental/efeitos adversos , Feminino , Predisposição Genética para Doença , Humanos , Estudos Longitudinais , Masculino , Neoplasias/etiologia , Estudos Observacionais como Assunto , Estudos Prospectivos , Fatores de Risco , Especificidade da Espécie , Inquéritos e Questionários , Pesquisa Translacional Biomédica , Estados Unidos
17.
Ann Surg Oncol ; 22(11): 3687-94, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25672563

RESUMO

BACKGROUND: This study aimed to assess the safety of robotic surgery for older women undergoing surgery for endometrial cancer. METHODS: A retrospective chart review of women undergoing surgery for endometrial cancer between October 2010 and December 2012 was conducted at the authors' institution. This cohort was divided by age (≥65 vs <65 years) and surgical approach (laparotomy vs robotic surgery). Postoperative morbidity and mortality were compared using standard statistical analysis. RESULTS: Of 228 patients identified, 73 (32 %) were 65 years old or older, and 98 (43 %) had undergone robotic surgery. Among the robotic surgery patients, women 65 years old or older had a higher Charlson comorbidity score (7.6 vs 4.9; p < 0.01) and were more likely to undergo pelvic lymphadenectomy (73 vs 39 %; p < 0.01). The complication rates did not differ between the groups except for increased urinary retention in the older group (15 % vs 3 %; p = 0.04). Older patients had a longer hospital stay (2.2 vs 1.3 days; p < 0.01) and a similar rate of discharge home (100 vs 96 %; p = 0.09). For the patients 65 years old or older, robotic surgery was associated with less blood loss (131 vs 235 ml; p = 0.03), a lower rate of ileus (0 vs 15 %; p = 0.04), a lower perioperative surgical complication rate (4 vs 30 %; p = 0.01), a shorter hospital stay (2.2 vs 4.4 days; p < 0.01), and a similar rate of discharge home (96 vs 91 %; p = 0.45) compared with laparotomy. CONCLUSION: Robotic surgery appears to be associated with less postoperative morbidity than laparotomy for endometrial cancer staging in women 65 years old or older. The complication rates after robotic surgery were similar between the two age groups.


Assuntos
Neoplasias do Endométrio/patologia , Neoplasias do Endométrio/cirurgia , Laparotomia , Excisão de Linfonodo , Procedimentos Cirúrgicos Robóticos , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Perda Sanguínea Cirúrgica , Feminino , Humanos , Histerectomia , Íleus/etiologia , Laparotomia/efeitos adversos , Tempo de Internação , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Ovariectomia , Alta do Paciente/estatística & dados numéricos , Pelve , Procedimentos Cirúrgicos Robóticos/efeitos adversos , Salpingectomia , Retenção Urinária/etiologia
18.
RNA ; 21(1): 61-74, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25404562

RESUMO

Post-transcriptional tRNA modifications are critical for efficient and accurate translation, and have multiple different roles. Lack of modifications often leads to different biological consequences in different organisms, and in humans is frequently associated with neurological disorders. We investigate here the conservation of a unique circuitry for anticodon loop modification required for healthy growth in the yeast Saccharomyces cerevisiae. S. cerevisiae Trm7 interacts separately with Trm732 and Trm734 to 2'-O-methylate three substrate tRNAs at anticodon loop residues C32 and N34, and these modifications are required for efficient wybutosine formation at m(1)G37 of tRNA(Phe). Moreover, trm7Δ and trm732Δ trm734Δ mutants grow poorly due to lack of functional tRNA(Phe). It is unknown if this circuitry is conserved and important for tRNA(Phe) modification in other eukaryotes, but a likely human TRM7 ortholog is implicated in nonsyndromic X-linked intellectual disability. We find that the distantly related yeast Schizosaccharomyces pombe has retained this circuitry for anticodon loop modification, that S. pombe trm7Δ and trm734Δ mutants have more severe phenotypes than the S. cerevisiae mutants, and that tRNA(Phe) is the major biological target. Furthermore, we provide evidence that Trm7 and Trm732 function is widely conserved throughout eukaryotes, since human FTSJ1 and THADA, respectively, complement growth defects of S. cerevisiae trm7Δ and trm732Δ trm734Δ mutants by modifying C32 of tRNA(Phe), each working with the corresponding S. cerevisiae partner protein. These results suggest widespread importance of 2'-O-methylation of the tRNA anticodon loop, implicate tRNA(Phe) as the crucial substrate, and suggest that this modification circuitry is important for human neuronal development.


Assuntos
Processamento Pós-Transcricional do RNA , RNA de Transferência de Fenilalanina/genética , Sequência de Aminoácidos , Animais , Anticódon , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster , Humanos , Metiltransferases/genética , Metiltransferases/metabolismo , Dados de Sequência Molecular , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , RNA de Transferência de Fenilalanina/metabolismo , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Schizosaccharomyces/genética , Proteínas de Schizosaccharomyces pombe/genética , Proteínas de Schizosaccharomyces pombe/metabolismo , tRNA Metiltransferases/genética , tRNA Metiltransferases/metabolismo
19.
Front Neural Circuits ; 8: 118, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25324727

RESUMO

Luminance vision has high spatial resolution and is used for form vision and texture discrimination. In humans, birds and bees luminance channel is spectrally selective-it depends on the signals of the long-wavelength sensitive photoreceptors (bees) or on the sum of long- and middle-wavelength sensitive cones (humans), but not on the signal of the short-wavelength sensitive (blue) photoreceptors. The reasons of such selectivity are not fully understood. The aim of this study is to reveal the inputs of cone signals to high resolution luminance vision in reef fish. Sixteen freshly caught damselfish, Pomacentrus amboinensis, were trained to discriminate stimuli differing either in their color or in their fine patterns (stripes vs. cheques). Three colors ("bright green", "dark green" and "blue") were used to create two sets of color and two sets of pattern stimuli. The "bright green" and "dark green" were similar in their chromatic properties for fish, but differed in their lightness; the "dark green" differed from "blue" in the signal for the blue cone, but yielded similar signals in the long-wavelength and middle-wavelength cones. Fish easily learned to discriminate "bright green" from "dark green" and "dark green" from "blue" stimuli. Fish also could discriminate the fine patterns created from "dark green" and "bright green". However, fish failed to discriminate fine patterns created from "blue" and "dark green" colors, i.e., the colors that provided contrast for the blue-sensitive photoreceptor, but not for the long-wavelength sensitive one. High resolution luminance vision in damselfish, Pomacentrus amboinensis, does not have input from the blue-sensitive cone, which may indicate that the spectral selectivity of luminance channel is a general feature of visual processing in both aquatic and terrestrial animals.


Assuntos
Percepção de Cores/fisiologia , Sensibilidades de Contraste/fisiologia , Percepção Espacial/fisiologia , Visão Ocular/fisiologia , Adaptação Ocular , Animais , Comportamento de Escolha/fisiologia , Condicionamento Operante , Peixes , Estimulação Luminosa , Células Fotorreceptoras Retinianas Cones/classificação , Células Fotorreceptoras Retinianas Cones/fisiologia
20.
Genes Dev ; 28(15): 1721-32, 2014 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-25085423

RESUMO

Sequence variation in tRNA genes influences the structure, modification, and stability of tRNA; affects translation fidelity; impacts the activity of numerous isodecoders in metazoans; and leads to human diseases. To comprehensively define the effects of sequence variation on tRNA function, we developed a high-throughput in vivo screen to quantify the activity of a model tRNA, the nonsense suppressor SUP4oc of Saccharomyces cerevisiae. Using a highly sensitive fluorescent reporter gene with an ochre mutation, fluorescence-activated cell sorting of a library of SUP4oc mutant yeast strains, and deep sequencing, we scored 25,491 variants. Unexpectedly, SUP4oc tolerates numerous sequence variations, accommodates slippage in tertiary and secondary interactions, and exhibits genetic interactions that suggest an alternative functional tRNA conformation. Furthermore, we used this methodology to define tRNA variants subject to rapid tRNA decay (RTD). Even though RTD normally degrades tRNAs with exposed 5' ends, mutations that sensitize SUP4oc to RTD were found to be located throughout the sequence, including the anti-codon stem. Thus, the integrity of the entire tRNA molecule is under surveillance by cellular quality control machinery. This approach to assess activity at high throughput is widely applicable to many problems in tRNA biology.


Assuntos
Estabilidade de RNA/genética , RNA de Transferência/genética , RNA de Transferência/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Citometria de Fluxo , Variação Genética , Ensaios de Triagem em Larga Escala , Mutação/genética , Conformação de Ácido Nucleico , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo
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