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1.
PLoS Genet ; 13(2): e1006611, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-28182654

RESUMEN

Germ cells contain non-membrane bound cytoplasmic organelles that help maintain germline integrity. In C. elegans they are called P granules; without them, the germline undergoes partial masculinization and aberrant differentiation. One key P-granule component is the Argonaute CSR-1, a small-RNA binding protein that antagonizes accumulation of sperm-specific transcripts in developing oocytes and fine-tunes expression of proteins critical to early embryogenesis. Loss of CSR-1 complex components results in a very specific, enlarged P-granule phenotype. In a forward screen to identify mutants with abnormal P granules, ten alleles were recovered with a csr-1 P-granule phenotype, eight of which contain mutations in known components of the CSR-1 complex (csr-1, ego-1, ekl-1, and drh-3). The remaining two alleles are in a novel gene now called elli-1 (enlarged germline granules). ELLI-1 is first expressed in primordial germ cells during mid-embryogenesis, and continues to be expressed in the adult germline. While ELLI-1 forms cytoplasmic aggregates, they occasionally dock, but do not co-localize with P granules. Instead, the majority of ELLI-1 aggregates accumulate in the shared germline cytoplasm. In elli-1 mutants, several genes that promote RNAi and P-granule accumulation are upregulated, and embryonic lethality, sterility, and RNAi resistance in a hypomorphic drh-3 allele is enhanced, suggesting that ELLI-1 functions with CSR-1 to modulate RNAi activity, P-granule accumulation, and post-transcriptional expression in the germline.


Asunto(s)
Proteínas de Caenorhabditis elegans/genética , Caenorhabditis elegans/genética , Gránulos Citoplasmáticos/metabolismo , Células Germinativas/metabolismo , Interferencia de ARN , Factores Generales de Transcripción/genética , Alelos , Animales , Animales Modificados Genéticamente , Secuencia de Bases , Caenorhabditis elegans/embriología , Caenorhabditis elegans/crecimiento & desarrollo , Proteínas de Caenorhabditis elegans/metabolismo , ARN Helicasas DEAD-box/genética , ARN Helicasas DEAD-box/metabolismo , Perfilación de la Expresión Génica/métodos , Regulación del Desarrollo de la Expresión Génica , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Inmunohistoquímica , Hibridación Fluorescente in Situ , Microscopía Fluorescente , Mutación , Proteínas de Unión al ARN/genética , Proteínas de Unión al ARN/metabolismo , ARN Polimerasa Dependiente del ARN/genética , ARN Polimerasa Dependiente del ARN/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Factores Generales de Transcripción/metabolismo
2.
Pathobiology ; 83(2-3): 140-7, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27100885

RESUMEN

OBJECTIVES: 3D histology tissue modeling is a useful analytical technique for understanding anatomy and disease at the cellular level. However, the current accuracy of 3D histology technology is largely unknown, and errors, misalignment and missing information are common in 3D tissue reconstruction. We used micro-CT imaging technology to better understand these issues and the relationship between fresh tissue and its 3D histology counterpart. METHODS: We imaged formalin-fixed and 2% Lugol-stained mouse brain, human uterus and human lung tissue with micro-CT. We then conducted image analyses on the tissues before and after paraffin embedding using 3D Slicer and ImageJ software to understand how tissue changes between the fixation and embedding steps. RESULTS: We found that all tissue samples decreased in volume by 19.2-61.5% after embedding, that micro-CT imaging can be used to assess the integrity of tissue blocks, and that micro-CT analysis can help to design an optimized tissue-sectioning protocol. CONCLUSIONS: Micro-CT reference data help to identify where and to what extent tissue was lost or damaged during slide production, provides valuable anatomical information for reconstructing missing parts of a 3D tissue model, and aids in correcting reconstruction errors when fitting the image information in vivo and ex vivo.


Asunto(s)
Procesamiento de Imagen Asistido por Computador/métodos , Imagenología Tridimensional/métodos , Microtomografía por Rayos X/métodos , Animales , Encéfalo/citología , Femenino , Histología , Humanos , Pulmón/citología , Ratones , Modelos Anatómicos , Adhesión en Parafina , Estándares de Referencia , Útero/citología
3.
J Appl Lab Med ; 8(6): 1092-1100, 2023 11 02.
Artículo en Inglés | MEDLINE | ID: mdl-37702018

RESUMEN

BACKGROUND: Specimens contaminated with intravenous (IV) fluids are common in clinical laboratories. Current methods for detecting contamination rely on insensitive and workflow-disrupting delta checks or manual technologist review. Herein, we assessed the utility of large language models for detecting contamination by IV crystalloids and compared its performance to multiple, but variably trained healthcare personnel (HCP). METHODS: Contamination of basic metabolic panels was simulated using 0.9% normal saline (NS), with (n = 30) and without (n = 30) 5% dextrose (D5NS), at mixture ratios of 0.10 and 0.25. A multimodal language model (GPT-4) and a diverse panel of 8 HCP were asked to adjudicate between real and contaminated results. Classification performance, mixture quantification, and confidence was compared by Wilcoxon rank sum. RESULTS: The 95% CIs for accuracy were 0.57-0.71 vs 0.73-0.80 for GPT-4 and HCP, respectively, on the NS set and 0.57-0.57 vs 0.73-0.80 on the D5NS set. HCP overestimated severity of contamination in the 0.10 mixture group (95% CI of estimate error, 0.05-0.20) for both fluids, while GPT-4 markedly overestimated the D5NS mixture at both ratios (0.16-0.33 for NS, 0.11-0.35 for D5NS). There was no correlation between reported confidence and likelihood of a correct classification. CONCLUSIONS: GPT-4 is less accurate than trained HCP for detecting IV fluid contamination of basic metabolic panel results. However, trained individuals were imperfect at identifying contaminated specimens implying the need for novel, automated tools for its detection.


Asunto(s)
Glucosa , Humanos
4.
Int J Surg ; 52: 74-81, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29425829

RESUMEN

Post hepatectomy liver failure (PHLF) remains a significant cause of morbidity and mortality after major liver resection. Although the etiology of PHLF is multifactorial, an inadequate functional liver remnant (FLR) is felt to be the most important modifiable predictor of PHLF. Pre-operative evaluation of FLR function and volume is of paramount importance before proceeding with any major liver resection. Patients with inadequate or borderline FLR volume must be considered for volume optimization strategies such as portal vein embolization (PVE), two stage hepatectomy with portal vein ligation (PVL), Yttrium-90 radioembolization, and associating liver partition and portal vein ligation for staged hepatectomy (ALPPS). This paper provides an overview of assessing FLR volume and function, and discusses indications and outcomes of commonly used volume optimization strategies.


Asunto(s)
Hepatectomía/efectos adversos , Fallo Hepático/etiología , Hígado/fisiopatología , Embolización Terapéutica/efectos adversos , Embolización Terapéutica/métodos , Femenino , Humanos , Ligadura/efectos adversos , Ligadura/métodos , Hígado/cirugía , Regeneración Hepática , Masculino , Vena Porta/cirugía , Guías de Práctica Clínica como Asunto , Cuidados Preoperatorios/métodos , Factores de Riesgo , Resultado del Tratamiento , Procedimientos Quirúrgicos Vasculares/efectos adversos
5.
J Am Coll Surg ; 226(4): 484-494, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29360615

RESUMEN

BACKGROUND: Biliary complications (BCs) affect up to to 34% of liver transplant recipients and are a major source of morbidity and cost. This is a 13-year review of BCs after liver transplantation (LT) at a tertiary care center. STUDY DESIGN: We conducted a single-center retrospective review of our prospective database to assess BCs in adult (aged 18 years or older) liver transplant recipients during a 13-year period (2002 to 2014). Biliary complications were divided into 3 subgroups: leak alone (L), stricture alone (S), and both leak and strictures (LS). Controls (no BCs) were used for comparison. RESULTS: There were 1,041 adult LTs performed during the study period; BCs developed in 239 (23%) of these patients: 55 (23%) L, 148 (62%) S, and 36 (15%) LS. One hundred and two (43%) were early (less than 30 d). Surgical revision was required in 42 cases (17%) (30 L, 10 LS, and 2 S), while the remaining 197 (83%) were managed nonsurgically (25 L, 26 LS, and 146 S), with a mean of 4.2 interventions/patient. One-, 3-, and 5-year overall patient and graft survival was significantly reduced in patients with bile leaks (84%, 71%, and 68% and 76%, 67%, and 64%, respectively) compared with controls (90%, 84%, and 78% and 88%, 81%, and 76%, respectively [p < 0.05]). Patients with BCs had higher incidence of cholestatic liver disease, higher pre-LT bilirubin, higher use of T-tubes, higher use of donor after cardiac death grafts, and higher rates of acute rejection (p < 0.05). Patients with BCs had longer ICU and hospital stays and higher rates of 30- and 90-day readmissions (p < 0.01). Multivariate analysis identified cholestatic liver disease, Roux-en-Y anastomosis, donor risk index >2, and T-tubes as independent BC predictors. CONCLUSIONS: Biliary complications after LT can significantly decrease patient and graft survival rates. Careful donor and recipient selection and attention to anastomotic technique can reduce BCs and improve outcomes.


Asunto(s)
Enfermedades de las Vías Biliares/epidemiología , Fallo Hepático/mortalidad , Fallo Hepático/cirugía , Trasplante de Hígado/efectos adversos , Complicaciones Posoperatorias/epidemiología , Adulto , Enfermedades de las Vías Biliares/diagnóstico , Femenino , Supervivencia de Injerto , Humanos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/diagnóstico , Estudios Retrospectivos , Tasa de Supervivencia , Centros de Atención Terciaria
6.
Int J Surg ; 53: 339-344, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29654968

RESUMEN

BACKGROUND: Increasing use of Living Donor Kidney Transplantation (LDKT) would decrease the discrepancy between patients awaiting transplantation and organ availability. Minimally invasive surgical approaches attempt to improve outcomes and foster living donation. This report compares outcomes of open minimal incision nephrectomy (Mini N) and a hand assisted laparoscopic nephrectomy (HALN). METHODS: This is a retrospective analysis of a prospectively maintained clinical database of LDKT using HALN or Mini N at a single institution between July 2007 and December 2015. Donor and recipient demographics, relevant pre-, intra- and post-operative factors, outcomes such as patient and graft survival rates, and complications were evaluated. RESULTS: Four hundred and fifty-four adult LDKT (243 Mini N, 211 HALN) were performed during the study period. Recipient and donor demographics were comparable except for higher BMI (p = 0.027) in HALN donors. One-, 3- and 5-year patient and graft survival rates were comparable. Six HALN donors experienced infectious wound complications or superficial skin dehiscence; none did in the Mini N group (p = 0.009). Eight HALN donors and one Mini N donor required an incisional hernia repair (p = 0.014). Recipients had similar warm ischemia times (33 v. 35 min, p = 0.491), but recipient surgeons of HALN nephrectomies subjectively noted higher anastomotic difficulty (10.4% v. 4.5%, p = 0.0183). Other parameters were similar between groups. CONCLUSION: Both Mini N and HALN provide similar long term recipient and donor outcomes. Offering techniques such as Mini N and HALN for living donor kidney procurement facilitates the opportunity to provide living donors safer and better tolerated nephrectomy procedures.


Asunto(s)
Laparoscópía Mano-Asistida , Trasplante de Riñón , Donadores Vivos , Procedimientos Quirúrgicos Mínimamente Invasivos/métodos , Nefrectomía/métodos , Adulto , Estudios de Cohortes , Femenino , Humanos , Masculino , Complicaciones Posoperatorias , Estudios Retrospectivos
7.
G3 (Bethesda) ; 5(10): 2209-15, 2015 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-26100681

RESUMEN

In Caenorhabditis elegans, germline expression programs are actively repressed in somatic tissue by components of the synMuv (synthetic multi-vulva) B chromatin remodeling complex, which include homologs of tumor suppressors Retinoblastoma (Rb/LIN-35) and Malignant Brain Tumor (MBT/LIN-61). However, the full scope of pathways that suppress germline expression in the soma is unknown. To address this, we performed a mutagenesis and screened for somatic expression of GFP-tagged PGL-1, a core P-granule nucleating protein. Eight alleles were isolated from 4000 haploid genomes. Five of these alleles exhibit a synMuv phenotype, whereas the remaining three were identified as hypomorphic alleles of known synMuv B genes, lin-13 and dpl-1. These findings suggest that most suppressors of germline programs in the soma of C. elegans are either required for viability or function through synMuv B chromatin regulation.


Asunto(s)
Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Proteínas Represoras/genética , Proteínas Represoras/metabolismo , Alelos , Animales , Animales Modificados Genéticamente , Mapeo Cromosómico , Expresión Génica , Genes Reporteros , Células Germinativas , Mutación , Interferencia de ARN , Proteínas de Unión al ARN/genética , Proteínas de Unión al ARN/metabolismo
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