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1.
Development ; 149(2)2022 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-35005773

RESUMEN

Amputation injuries in mammals are typically non-regenerative; however, joint regeneration is stimulated by BMP9 treatment, indicating the presence of latent articular chondrocyte progenitor cells. BMP9 induces a battery of chondrogenic genes in vivo, and a similar response is observed in cultures of amputation wound cells. Extended cultures of BMP9-treated cells results in differentiation of hyaline cartilage, and single cell RNAseq analysis identified wound fibroblasts as BMP9 responsive. This culture model was used to identify a BMP9-responsive adult fibroblast cell line and a culture strategy was developed to engineer hyaline cartilage for engraftment into an acutely damaged joint. Transplanted hyaline cartilage survived engraftment and maintained a hyaline cartilage phenotype, but did not form mature articular cartilage. In addition, individual hypertrophic chondrocytes were identified in some samples, indicating that the acute joint injury site can promote osteogenic progression of engrafted hyaline cartilage. The findings identify fibroblasts as a cell source for engineering articular cartilage and establish a novel experimental strategy that bridges the gap between regeneration biology and regenerative medicine.


Asunto(s)
Diferenciación Celular , Fibroblastos/citología , Cartílago Hialino/citología , Regeneración , Ingeniería de Tejidos/métodos , Animales , Células Cultivadas , Condrocitos/citología , Condrocitos/efectos de los fármacos , Condrogénesis , Fibroblastos/efectos de los fármacos , Factor 2 de Diferenciación de Crecimiento/farmacología , Cartílago Hialino/metabolismo , Cartílago Hialino/fisiología , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos NOD , Ratones SCID
2.
J Biol Chem ; 299(6): 104838, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37209821

RESUMEN

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a cerebral small vessel disease that results from mutations in NOTCH3. How mutations in NOTCH3 ultimately result in disease is not clear, although there is a predilection for mutations to alter the number of cysteines of the gene product, supporting a model in which alterations of conserved disulfide bonds of NOTCH3 drives the disease process. We have found that recombinant proteins with CADASIL NOTCH3 EGF domains 1 to 3 fused to the C terminus of Fc are distinguished from wildtype proteins by slowed mobility in nonreducing gels. We use this gel mobility shift assay to define the effects of mutations in the first three EGF-like domains of NOTCH3 in 167 unique recombinant protein constructs. This assay permits a readout on NOTCH3 protein mobility that indicates that (1) any loss of cysteine mutation in the first three EGF motifs results in structural abnormalities; (2) for loss of cysteine mutants, the mutant amino acid residue plays a minimal role; (3) the majority of changes that result in a new cysteine are poorly tolerated; (4) at residue 75, only cysteine, proline, and glycine induce structural shifts; (5) specific second mutations in conserved cysteines suppress the impact of loss of cysteine CADASIL mutations. These studies support the importance of NOTCH3 cysteines and disulfide bonds in maintaining normal protein structure. Double mutant analysis suggests that suppression of protein abnormalities can be achieved through modification of cysteine reactivity, a potential therapeutic strategy.


Asunto(s)
CADASIL , Receptor Notch3 , Humanos , CADASIL/genética , Cisteína/genética , Cisteína/metabolismo , Disulfuros , Factor de Crecimiento Epidérmico/genética , Mutación , Receptor Notch3/genética
3.
Angew Chem Int Ed Engl ; : e202406214, 2024 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-38825853

RESUMEN

Crystal polymorphism, characterized by different packing arrangements of the same compound, strongly ties to the physical properties of a molecule. Determining the polymorphic landscape is complex and time-consuming, with the number of experimentally observed polymorphs varying widely from molecule to molecule. Furthermore, disappearing polymorphs, the phenomenon whereby experimentally observed forms cannot be reproduced, pose a significant challenge for the pharmaceutical industry. Herein, we focused on oxindole (OX), a small rigid molecule with four known polymorphs, including a reported disappearing form. Using crystal structure prediction (CSP), we assessed OX solid-state landscape and thermodynamic stability by comparing predicted structures with experimentally known forms. We then performed melt and solution crystallization in bulk and nanoconfinement to validate our predictions. These experiments successfully reproduced the known forms and led to the discovery of four novel polymorphs. Our approach provided insights into reconstructing disappearing polymorphs and building more comprehensive polymorph landscapes. These results also establish a new record of packing polymorphism for rigid molecules.

4.
J Am Chem Soc ; 145(40): 21738-21744, 2023 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-37787499

RESUMEN

We report a light-driven method for the intermolecular anti-Markovnikov hydroamination of alkenes with primary heteroaryl amines. In this protocol, electron transfer between an amine substrate and an excited-state iridium photocatalyst affords an aminium radical cation (ARC) intermediate that undergoes C-N bond formation with a nucleophilic alkene. Integral to reaction success is the electronic character of the amine, wherein increasingly electron-deficient heteroaryl amines generate increasingly reactive ARCs. Counteranion-dependent reactivity is observed, and iridium triflate photocatalysts are employed in place of conventional iridium hexafluorophosphate complexes. This method exhibits broad functional group tolerance across 55 examples of N-alkylated products derived from pharmaceutically relevant heteroaryl amines.

5.
Stat Med ; 42(8): 1263-1276, 2023 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-36705055

RESUMEN

Incomplete coverage by cancer registries can lead to an underreporting of cancers and a resulting bias in risk estimates. When registries are defined by geographic region, gaps in observation can arise for individuals who reside outside of or migrate from the total registry catchment area. Moreover, the exact periods of non-observation for an individual may be unknown due to intermittent reporting of residential histories. The motivating example for this work is the U.S. Radiologic Technologist (USRT) study which ascertained cancer outcomes for a national cohort through 43 state/regional registries; similar gaps in outcome ascertainment can appear in other registry or electronic health record- based cohort studies. We propose a two-step procedure for estimating relative and absolute risk in these settings. First, using a mover stayer model fitted to individuals' known residential history, we obtain individual posterior probabilities of residing outside the registry catchment area each year. Second, we incorporate these probabilities in the survival data likelihood for competing risks to account for unobserved events. We assess the performance of the proposed method in extensive simulation studies. Compared to several simple alternative approaches, the proposed method reduces bias and improves efficiency. Finally, we apply the proposed method to a study of first primary lung cancers in the USRT cohort.


Asunto(s)
Neoplasias , Humanos , Riesgo , Probabilidad , Simulación por Computador , Estudios de Cohortes , Sistema de Registros
6.
Arch Womens Ment Health ; 26(6): 793-801, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37673838

RESUMEN

A large number of studies have reported that sensory gating disorders represented by P50 inhibition may be involved in the pathophysiological process of schizophrenia. However, few studies have explored the relationship between sensory gating disorders and cognitive dysfunction in patients with schizophrenia. This study aimed to explore sex differences in the relationship between cognitive and P50 deficits in patients with chronic schizophrenia, which has not been reported. A total of 183 chronic schizophrenia patients (128 males and 55 females) and 166 healthy controls (76 males and 90 females) participated in this study. The MATRICS Consensus Cognitive Battery (MCCB) was measured for cognitive function and P50 components for the sensory gating in all participants. The Positive and Negative Syndrome Scales (PANSS) was used to assess the psychopathological symptoms in patients. Female patients performed significantly better than male patients in several cognitive domains of MCCB (all p < 0.01). There were no significant differences in P50 components between male and female patients (all p > 0.05). Further analysis showed that in female patients, latency of S2 was negatively correlated with reasoning and problem-solving domain of MCCB (p < 0.05), and P50 ratio was negatively correlated with social cognition domain of MCCB (p < 0.05). In male patients, there was no any correlation between P50 and cognitive domains of MCCB. Our results suggest that there is a sex difference in the association between P50 deficiency and cognitive impairment in Chinese Han patients with schizophrenia.


Asunto(s)
Esquizofrenia , Caracteres Sexuales , Humanos , Masculino , Femenino , Esquizofrenia/diagnóstico , Cognición , Pueblo Asiatico , Filtrado Sensorial/fisiología , Pruebas Neuropsicológicas
7.
Eur J Gynaecol Oncol ; 44(1): 17-25, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36874058

RESUMEN

Bevacizumab has demonstrated significant benefit in recurrent ovarian, fallopian tube and peritoneal cancer (OC), but its optimal position within the sequence of systemic therapies remains controversial. Since rebound progression after bevacizumab has been observed in other cancers, and because bevacizumab is incorporated in several regimens used in the recurrent setting, the duration of treatment may impact survival. We sought to identify whether earlier bevacizumab exposure is associated with prolonged bevacizumab therapy and survival by conducting a multi-institution retrospective study of recurrent OC patients treated with bevacizumab from 2004-2014. Multivariate logistic regression identified factors associated with receiving more than six bevacizumab cycles. Overall survival by duration and ordinal sequence of bevacizumab therapy were evaluated using logrank testing and Cox regression. In total, 318 patients were identified. 89.1% had stage III or IV disease; 36% had primary platinum resistance; 40.5% received two or fewer prior chemotherapy regimens. Multivariate logistic regression demonstrated that primary platinum sensitivity (Odds Ratio (OR) 2.34, p = 0.001) or initiating bevacizumab at the first or second recurrence (OR 2.73, p < 0.001) were independently associated with receiving more than six cycles of bevacizumab. Receiving more cycles of bevacizumab was associated with improved overall survival whether measured from time of diagnosis (logrank p < 0.001), bevacizumab initiation (logrank p < 0.001), or bevacizumab discontinuation (logrank p = 0.017). Waiting one additional recurrence to initiate bevacizumab resulted in a 27% increased hazard of death (Hazard Ratio (HR) 1.27, p < 0.001) by multivariate analysis. In conclusion, patients with primary platinum sensitive disease who received fewer prior lines of chemotherapy were able to receive more cycles of bevacizumab, which was associated with improved overall survival. Survival worsened when bevacizumab was initiated later in the ordinal sequence of therapies.

8.
Int Urogynecol J ; 33(4): 897-902, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-34264355

RESUMEN

OBJECTIVES AND HYPOTHESIS: The primary objective is to measure the difference in urinary tract infection (UTI) rates within 6  weeks of placement of a retropubic mid-urethral sling (RMUS) in the setting of various postoperative prophylactic antibiotic regimens. UTI rates were measured by antibiotic prescriptions to treat UTI and/or culture. Secondary aims included determining risk factors for postoperative UTI. METHODS: A retrospective chart review from 2014 to 2016 was performed at Baylor Scott and White Medical Center-Temple for CPT code 57288. Univariate comparisons were performed using chi-square and Student's t-test. Logistic regression analysis was performed for UTI risk factors with univariate p values ≤ 0.1. RESULTS: One hundred twelve subjects were included. Seventeen (15%) were treated for postoperative UTI. Postoperative prophylactic antibiotics included trimethoprim (39.3%), nitrofurantoin (31.3%), trimethoprim-sulfamethoxazole (5.4%), ciprofloxacin (2.7%), and cephalexin (1.8%). Ninety subjects were prescribed postoperative prophylactic antibiotics (80.4%). The postoperative UTI rate was not significantly different between those who were prescribed postoperative prophylactic antibiotics (16%) and those who were not (14%). None of the treatments showed a significant difference on postoperative UTI rate compared to no treatment. Significant risk factors for UTI included catheterization past postoperative day 1 (OR 6.4, 95% CI 1.7 - 23.8; p  = 0.006). CONCLUSIONS: There was no significant difference in postoperative UTI rate in the group without postoperative prophylactic antibiotics compared to those who did receive it. Catheterization past postoperative day 1 was significantly associated with postoperative UTI. However, definitive conclusions are limited by a lack of power.


Asunto(s)
Cabestrillo Suburetral , Infecciones Urinarias , Antibacterianos/uso terapéutico , Femenino , Humanos , Masculino , Nitrofurantoína , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/prevención & control , Estudios Retrospectivos , Cabestrillo Suburetral/efectos adversos , Infecciones Urinarias/epidemiología , Infecciones Urinarias/etiología , Infecciones Urinarias/prevención & control
9.
Neurourol Urodyn ; 40(6): 1686-1694, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34196027

RESUMEN

AIMS: This is a prospective cohort study comparing de novo lower urinary tract symptoms (LUTS) in subjects undergoing a retropubic mid-urethral sling who either did or did not develop a postoperative retropubic hematoma within 6 weeks of surgery. The secondary objective was to measure the incidence and prevalence of retropubic hematomas, and subject characteristics associated with retropubic hematomas. METHODS: Eligible subjects were recruited before undergoing a retropubic mid-urethral sling with or without concurrent pelvic reconstructive surgery. Validated urinary symptom questionnaires were completed before surgery and at 6 weeks postoperatively. An abdominal ultrasound was used to establish baseline lower urinary tract imaging. Ultrasound was repeated immediately after surgery and 6 weeks later to assess for the presence of retropubic hematomas. RESULTS: Ninety-four subjects were enrolled. Baseline urgency and frequency were measured in 35% (33/93) of subjects. At 6 weeks postoperatively, 2% (1/52) had de novo LUTS which were not associated with a retropubic hematoma at any time. Immediately after surgery, the incidence of retropubic hematomas was 17% (16/94) while the prevalence of retropubic hematomas 6 weeks after surgery was 4% (3/75). There was no significant difference in the change in hemoglobin before and after surgery between those with and without postoperative retropubic hematomas. CONCLUSIONS: There is no significant association with de novo LUTS and retropubic hematomas. Though there is a 17% incidence of retropubic hematomas detected immediately after surgery, those with hematomas who were not lost to follow-up resolved by the 6-week postoperative visit and is of unclear clinical significance.


Asunto(s)
Cabestrillo Suburetral , Incontinencia Urinaria de Esfuerzo , Femenino , Hematoma/diagnóstico por imagen , Hematoma/epidemiología , Hematoma/etiología , Humanos , Estudios Prospectivos , Cabestrillo Suburetral/efectos adversos , Vejiga Urinaria/diagnóstico por imagen , Vejiga Urinaria/cirugía
10.
J Immunol ; 203(11): 2837-2849, 2019 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-31659014

RESUMEN

Interstitial lung disease (ILD) is a well-known extra-articular manifestation of rheumatoid arthritis (RA). RA-associated ILD (RA-ILD) exists on a wide spectrum, with variable levels of inflammatory and fibrotic activity, although all subtypes are regarded as irreversible pathologic conditions. In both articular and pulmonary manifestations, TNF is a significant pathogenic factor. Whereas anti-TNF therapy alleviates joint pathologic conditions, it exacerbates fibrotic RA-ILD. The TNF-transgenic (TNF-Tg) murine model of RA develops both inflammatory arthritis and an ILD that mimics a cellular nonspecific interstitial pneumonia pattern dominated by an interstitial accumulation of inflammatory cells with minimal-to-absent fibrosis. Given the model's potential to elucidate the genesis of inflammatory RA-ILD, we aim to achieve the following: 1) characterize the cellular accumulations in TNF-Tg lungs, and 2) assess the reversibility of inflammatory ILD following anti-TNF therapy known to resolve TNF-Tg inflammatory arthritis. TNF-Tg mice with established disease were randomized to anti-TNF or placebo therapy and evaluated with imaging, histology, and flow cytometric analyses, together with wild-type controls. Flow cytometry of TNF-Tg versus wild-type lungs revealed significant increases in activated monocytes, conventional dendritic cells, and CD21+/CD23- B cells that are phenotypically distinct from the B cells in inflamed nodes, which are known to accumulate in joint-draining lymph nodes. In contrast to human RA-ILD, anti-TNF treatment significantly alleviated both joint and lung inflammation. These results identify a potential role for activated monocytes, conventional dendritic cells, and CD21+/CD23- B cells in the genesis of RA-ILD, which exist in a previously unknown, reversible, prefibrotic stage of the disease.


Asunto(s)
Artritis Reumatoide/inmunología , Linfocitos B/inmunología , Modelos Animales de Enfermedad , Enfermedades Pulmonares Intersticiales/inmunología , Receptores de Complemento 3d/metabolismo , Receptores de IgE/metabolismo , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores , Factor de Necrosis Tumoral alfa/inmunología , Animales , Linfocitos B/metabolismo , Células Dendríticas/inmunología , Humanos , Ratones , Ratones Transgénicos , Monocitos/inmunología
11.
Int Urogynecol J ; 32(7): 1897-1905, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-32737534

RESUMEN

OBJECTIVE: To follow a prospective cohort of women during their first term pregnancy to elucidate the nature and timing of changes to the pelvic floor during pregnancy and after vaginal delivery. METHODS: Enrolled subjects were evaluated at four time points with dynamic MRI, POP-Q examinations, and validated symptom questionnaires. The four assessments occurred during the first trimester (ePG), late third trimester (lPG), within a week after vaginal delivery (ePP), and three months postpartum (lPP). Two-dimensional T1-weighted MRI measurements included bladder descent and area of the levator hiatus at rest and during Valsalva maneuvers. Sample size of ten subjects was calculated for a power of 0.8 to detect a 20% change in bladder position with p < 0.05. Comparative statistical tests were used for parametric and non-parametric data, respectively. RESULTS: Twelve subjects completed the study. At lPP, the bladder descent was increased (p = 0.03) at rest and with Valsalva compared to ePG. Levator hiatus area did not differ (p = 0.63) between time points at rest or with Valsalva. Median POP stage increased (p = 0.001) to 1.5 at lPP. Mean genital hiatus increased (p = 0.0003) at each time point. Higher scores were recorded on the UDI-6 (p < 0.001) and the PFDI-20 (p = 0.003) questionnaires at lPG and ePP, but returned to ePG levels by lPP. CONCLUSION: Anatomic changes measured by dynamic MRI and POP-Q examinations demonstrate significant descent at 3 months postpartum. However, these anatomic changes did not significantly correlate with changes in symptoms.


Asunto(s)
Diafragma Pélvico , Prolapso de Órgano Pélvico , Parto Obstétrico , Femenino , Humanos , Diafragma Pélvico/diagnóstico por imagen , Periodo Posparto , Embarazo , Tercer Trimestre del Embarazo , Estudios Prospectivos , Ultrasonografía
12.
Plant Biotechnol J ; 17(8): 1636-1645, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-30706638

RESUMEN

An efficient Agrobacterium-mediated site-specific integration (SSI) technology using the flipase/flipase recognition target (FLP/FRT) system in elite maize inbred lines is described. The system allows precise integration of a single copy of a donor DNA flanked by heterologous FRT sites into a predefined recombinant target line (RTL) containing the corresponding heterologous FRT sites. A promoter-trap system consisting of a pre-integrated promoter followed by an FRT site enables efficient selection of events. The efficiency of this system is dependent on several factors including Agrobacterium tumefaciens strain, expression of morphogenic genes Babyboom (Bbm) and Wuschel2 (Wus2) and choice of heterologous FRT pairs. Of the Agrobacterium strains tested, strain AGL1 resulted in higher transformation frequency than strain LBA4404 THY- (0.27% vs. 0.05%; per cent of infected embryos producing events). The addition of morphogenic genes increased transformation frequency (2.65% in AGL1; 0.65% in LBA4404 THY-). Following further optimization, including the choice of FRT pairs, a method was developed that achieved 19%-22.5% transformation frequency. Importantly, >50% of T0 transformants contain the desired full-length site-specific insertion. The frequencies reported here establish a new benchmark for generating targeted quality events compatible with commercial product development.


Asunto(s)
Agrobacterium tumefaciens , Recombinación Genética , Zea mays/genética , Plantas Modificadas Genéticamente , Regiones Promotoras Genéticas
13.
Plant Cell ; 28(9): 1998-2015, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27600536

RESUMEN

While transformation of the major monocot crops is currently possible, the process typically remains confined to one or two genotypes per species, often with poor agronomics, and efficiencies that place these methods beyond the reach of most academic laboratories. Here, we report a transformation approach involving overexpression of the maize (Zea mays) Baby boom (Bbm) and maize Wuschel2 (Wus2) genes, which produced high transformation frequencies in numerous previously nontransformable maize inbred lines. For example, the Pioneer inbred PHH5G is recalcitrant to biolistic and Agrobacterium tumefaciens transformation. However, when Bbm and Wus2 were expressed, transgenic calli were recovered from over 40% of the starting explants, with most producing healthy, fertile plants. Another limitation for many monocots is the intensive labor and greenhouse space required to supply immature embryos for transformation. This problem could be alleviated using alternative target tissues that could be supplied consistently with automated preparation. As a major step toward this objective, we transformed Bbm and Wus2 directly into either embryo slices from mature seed or leaf segments from seedlings in a variety of Pioneer inbred lines, routinely recovering healthy, fertile T0 plants. Finally, we demonstrated that the maize Bbm and Wus2 genes stimulate transformation in sorghum (Sorghum bicolor) immature embryos, sugarcane (Saccharum officinarum) callus, and indica rice (Oryza sativa ssp indica) callus.

14.
Exp Lung Res ; 45(7): 175-187, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31318607

RESUMEN

Purpose: Micro-computed tomography (µCT) is increasingly being used on animal models as a minimally-invasive longitudinal outcome measure of pulmonary disease progression. However, while imaging can elucidate macroscopic structural changes over the whole lung, µCT is unable to describe the mechanical changes and functional impairments imposed by progressive disease, which can only be measured via pulmonary function tests (PFTs). The tumor necrosis factor-transgenic (TNF-Tg) mouse model of rheumatoid arthritis (RA) develops pulmonary pathology that mimics many aspects of the inflammatory interstitial lung disease (ILD) seen in a subset of patients with RA. Prior studies using µCT imaging of these mice found increased pulmonary density, characteristic of restrictive disease; however, there have been conflicting reports in the literature regarding the obstructive versus restrictive phenotype of this model. Our study looks to 1) define the functional impairments and 2) characterize the restrictive/obstructive nature of the disease found in this model. Materials and Methods: In this study, we performed PFTs at end-stage ILD, and paired these findings with µCT results, correlating radiology to functional parameters. TNF-Tg and WT littermates of both sexes underwent µCT imaging and PFT testing at 5.5 months-old. Spearman's correlation analyses were performed comparing lung tissue volume (LTV) to PFT parameters of gas exchange and tissue stiffness. Results: Compared to WT, TNF-Tg mice had impaired gas exchange capacity, increased respiratory resistance, and reduced lung compliance, elastance, and inspiratory capacity, indicating increased tissue stiffness and compromised pulmonary function. LTV was also consistently higher in TNF-Tg lungs. Conclusions: These findings demonstrate that: 1) TNF-Tg mice display a restrictive pathology, and 2) in vivo µCT is a valid outcome measure to infer changes in pulmonary mechanical and functional parameters.


Asunto(s)
Modelos Animales de Enfermedad , Enfermedades Pulmonares Intersticiales/diagnóstico por imagen , Factor de Necrosis Tumoral alfa/genética , Microtomografía por Rayos X , Animales , Femenino , Enfermedades Pulmonares Intersticiales/patología , Enfermedades Pulmonares Intersticiales/fisiopatología , Masculino , Ratones Transgénicos , Tamaño de los Órganos , Intercambio Gaseoso Pulmonar , Pruebas de Función Respiratoria
15.
Chaos ; 29(8): 083107, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31472510

RESUMEN

We describe an analog stochastic switch that exhibits three distinct phases as its parameters change. The phases are classified by the mean and variance of the switch's output. A phase change appears if the mean or the variance tends to a finite value or to infinity. The switch can be embedded in a large gene regulatory network for which the moment equations naturally close at the second order. This switch was used to model the response of a heat-shock system.

16.
Plant Mol Biol ; 97(1-2): 187-200, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29687284

RESUMEN

KEY MESSAGE: A simple and versatile ternary vector system that utilizes improved accessory plasmids for rapid maize transformation is described. This system facilitates high-throughput vector construction and plant transformation. The super binary plasmid pSB1 is a mainstay of maize transformation. However, the large size of the base vector makes it challenging to clone, the process of co-integration is cumbersome and inefficient, and some Agrobacterium strains are known to give rise to spontaneous mutants resistant to tetracycline. These limitations present substantial barriers to high throughput vector construction. Here we describe a smaller, simpler and versatile ternary vector system for maize transformation that utilizes improved accessory plasmids requiring no co-integration step. In addition, the newly described accessory plasmids have restored virulence genes found to be defective in pSB1, as well as added virulence genes. Testing of different configurations of the accessory plasmids in combination with T-DNA binary vector as ternary vectors nearly doubles both the raw transformation frequency and the number of transformation events of usable quality in difficult-to-transform maize inbreds. The newly described ternary vectors enabled the development of a rapid maize transformation method for elite inbreds. This vector system facilitated screening different origins of replication on the accessory plasmid and T-DNA vector, and four combinations were identified that have high (86-103%) raw transformation frequency in an elite maize inbred.


Asunto(s)
Vectores Genéticos , Transformación Genética , Zea mays/genética , Agrobacterium tumefaciens/genética , ADN Bacteriano , ADN de Plantas , Plásmidos , Origen de Réplica
17.
Plant Biotechnol J ; 16(7): 1388-1395, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29327444

RESUMEN

Sorghum is the fifth most widely planted cereal crop in the world and is commonly cultivated in arid and semi-arid regions such as Africa. Despite its importance as a food source, sorghum genetic improvement through transgenic approaches has been limited because of an inefficient transformation system. Here, we report a ternary vector (also known as cohabitating vector) system using a recently described pVIR accessory plasmid that facilitates efficient Agrobacterium-mediated transformation of sorghum. We report regeneration frequencies ranging from 6% to 29% in Tx430 using different selectable markers and single copy, backbone free 'quality events' ranging from 45% to 66% of the total events produced. Furthermore, we successfully applied this ternary system to develop transformation protocols for popular but recalcitrant African varieties including Macia, Malisor 84-7 and Tegemeo. In addition, we report the use of this technology to develop the first stable CRISPR/Cas9-mediated gene knockouts in Tx430.


Asunto(s)
Agrobacterium/genética , Ingeniería Genética/métodos , Sorghum/genética , Sistemas CRISPR-Cas , Técnicas de Transferencia de Gen , Marcadores Genéticos/genética , Vectores Genéticos/genética , Plantas Modificadas Genéticamente/genética , Transformación Genética/genética
18.
Am J Obstet Gynecol ; 219(1): 78.e1-78.e9, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29630890

RESUMEN

BACKGROUND: Sacral neuromodulation is an effective therapy for overactive bladder, urinary retention, and fecal incontinence. Infection after sacral neurostimulation is costly and burdensome. Determining optimal perioperative management strategies to reduce the risk of infection is important to reduce this burden. OBJECTIVE: We sought to identify risk factors associated with sacral neurostimulator infection requiring explantation, to estimate the incidence of infection requiring explantation, and identify associated microbial pathogens. STUDY DESIGN: This is a multicenter retrospective case-control study of sacral neuromodulation procedures completed from Jan. 1, 2004, through Dec. 31, 2014. We identified all sacral neuromodulation implantable pulse generator implants as well as explants due to infection at 8 participating institutions. Cases were patients who required implantable pulse generator explantation for infection during the review period. Cases were included if age ≥18 years old, follow-up data were available ≥30 days after implantable pulse generator implant, and the implant was performed at the institution performing the explant. Two controls were matched to each case. These controls were the patients who had an implantable pulse generator implanted by the same surgeon immediately preceding and immediately following the identified case who met inclusion criteria. Controls were included if age ≥18 years old, no infection after implantable pulse generator implant, follow-up data were available ≥180 days after implant, and no explant for any reason <180 days from implant. Controls may have had an explant for reasons other than infection at >180 days after implant. Fisher exact test (for categorical variables) and Student t test (for continuous variables) were used to test the strength of the association between infection and patient and surgery characteristics. Significant variables were then considered in a multivariable logistic regression model to determine risk factors independently associated with infection. RESULTS: Over a 10-year period at 8 academic institutions, 1930 sacral neuromodulator implants were performed by 17 surgeons. In all, 38 cases requiring device explant for infection and 72 corresponding controls were identified. The incidence of infection requiring explant was 1.97%. Hematoma formation (13% cases, 0% controls; P = .004) and pocket depth of ≥3 cm (21% cases, 0% controls; P = .031) were independently associated with an increased risk of infection requiring explant. On multivariable regression analysis controlling for significant variables, both hematoma formation (P = .006) and pocket depth ≥3 cm (P = .020, odds ratio 3.26; 95% confidence interval, 1.20-8.89) remained significantly associated with infection requiring explant. Of the 38 cases requiring explant, 32 had cultures collected and 24 had positive cultures. All 5 cases with a hematoma had a positive culture (100%). Of the 4 cases with a pocket depth ≥3 cm, 2 had positive cultures, 1 had negative cultures, and 1 had a missing culture result. The most common organism identified was methicillin-resistant Staphylococcus aureus (38%). CONCLUSION: Infection after sacral neuromodulation requiring device explant is low. The most common infectious pathogen identified was methicillin-resistant S aureus. Demographic and health characteristics did not predict risk of explant due to infection, however, having a postoperative hematoma or a deep pocket ≥3 cm significantly increased the risk of explant due to infection. These findings highlight the importance of meticulous hemostasis as well as ensuring the pocket depth is <3 cm at the time of device implant.


Asunto(s)
Remoción de Dispositivos/estadística & datos numéricos , Incontinencia Fecal/terapia , Infecciones Relacionadas con Prótesis/epidemiología , Raíces Nerviosas Espinales , Infecciones Estafilocócicas/epidemiología , Estimulación Eléctrica Transcutánea del Nervio , Vejiga Urinaria Hiperactiva/terapia , Retención Urinaria/terapia , Adulto , Anciano , Antibacterianos/uso terapéutico , Estudios de Casos y Controles , Femenino , Humanos , Modelos Logísticos , Masculino , Staphylococcus aureus Resistente a Meticilina , Persona de Mediana Edad , Análisis Multivariante , Infecciones Relacionadas con Prótesis/terapia , Estudios Retrospectivos , Factores de Riesgo , Sacro , Nervios Espinales , Staphylococcus aureus
19.
South Med J ; 110(12): 782-784, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-29197313

RESUMEN

OBJECTIVES: Guidelines for use of prophylactic antibiotics in gynecologic procedures are outlined by the American Congress of Obstetricians and Gynecologists. There remains, however, a high rate of unindicated administration of antibiotics for surgeries. A retrospective study performed at our institution in 2012-2013 demonstrated that unindicated prophylactic antibiotics were administered over half the time. This study aimed to examine variations in the use of prophylactic antibiotics in patients undergoing gynecologic surgery at Scott and White Memorial Hospital and determine whether an educational intervention to gynecology physicians was associated with a significant decrease in unindicated prophylactic antibiotics. METHODS: A retrospective chart review was performed for all women undergoing gynecologic surgery at Scott and White Memorial Hospital in Temple, Texas for 1 year. An educational intervention regarding prophylactic antibiotic usage was held for obstetricians and gynecologists in the middle of that year. Subjects were included if they had procedures with a Current Procedural Terminology code corresponding to a procedure that does not require prophylactic antibiotics. Subjects were excluded if they had concurrent procedures for which antibiotics are recommended. RESULTS: A total of 500 subjects met inclusion and exclusion criteria, with 243 before the educational intervention and 257 after the intervention. In our study, a significant decrease (P < 0.0001) in unindicated prophylactic antibiotic use was demonstrated: from 45.7% (111/243) preintervention to 24.9% (64/257) postintervention. Before the educational intervention, both the gynecology oncology and reproductive endocrinology and infertility divisions had the highest rates of unindicated antibiotic use-91.7% (44/48) and 91.7% (33/36), respectively. The generalist and urogynecology divisions had the lowest rates for specialists before the intervention: 20.6% (30/146) and 30.8% (4/13), respectively. After the intervention, all of the divisions demonstrated an improvement in their rates of unindicated prophylactic antibiotic use. The urogynecology division demonstrated an improvement that can be considered clinically significant while not meeting statistical significance. The adverse event rates were not different between subjects who received preoperative prophylactic antibiotics (2.9%) and subjects who did not (2.8%). CONCLUSIONS: A simple educational intervention was associated with a significant decrease in unindicated prophylactic antibiotics in gynecologic procedures.


Asunto(s)
Antibacterianos/uso terapéutico , Profilaxis Antibiótica/estadística & datos numéricos , Procedimientos Quirúrgicos Ginecológicos/estadística & datos numéricos , Ginecología/educación , Prescripción Inadecuada/estadística & datos numéricos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Profilaxis Antibiótica/métodos , Femenino , Procedimientos Quirúrgicos Ginecológicos/educación , Humanos , Persona de Mediana Edad , Estudios Retrospectivos , Texas , Adulto Joven
20.
Traffic ; 15(3): 273-91, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24320232

RESUMEN

During synapse development, synaptic proteins must be targeted to sites of presynaptic release. Directed transport as well as local sequestration of synaptic vesicle precursors (SVPs), membranous organelles containing many synaptic proteins, might contribute to this process. Using neuron-wide time-lapse microscopy, we studied SVP dynamics in the DA9 motor neuron in Caenorhabditis elegans. SVP transport was highly dynamic and bi-directional throughout the entire neuron, including the dendrite. While SVP trafficking was anterogradely biased in axonal segments prior to the synaptic domain, directionality of SVP movement was stochastic in the dendrite and distal axon. Furthermore, frequency of movement and speed were variable between different compartments. These data provide evidence that SVP transport is differentially regulated in distinct neuronal domains. It also suggests that polarized SVP transport in concert with local vesicle capturing is necessary for accurate presynapse formation and maintenance. SVP trafficking analysis of two hypomorphs for UNC-104/KIF1A in combination with mathematical modeling identified directionality of movement, entry of SVPs into the axon as well as axonal speeds as the important determinants of steady-state SVP distributions. Furthermore, detailed dissection of speed distributions for wild-type and unc-104/kif1a mutant animals revealed an unexpected role for UNC-104/KIF1A in dendritic SVP trafficking.


Asunto(s)
Transporte Axonal , Caenorhabditis elegans/metabolismo , Neuronas Motoras/metabolismo , Vesículas Sinápticas/metabolismo , Animales , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Proteínas del Tejido Nervioso/genética , Proteínas del Tejido Nervioso/metabolismo
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