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The regulation of root Plasma membrane (PM) Intrinsic Protein (PIP)-type aquaporins (AQPs) is potentially important for salinity tolerance. However, the molecular and cellular details underlying this process in halophytes remain unclear. Using free-flow electrophoresis and label-free proteomics, we report that the increased abundance of PIPs at the PM of the halophyte ice plant (Mesembryanthemum crystallinum L.) roots under salinity conditions is regulated by clathrin-coated vesicles (CCV). To understand this regulation, we analyzed several components of the M. crystallinum CCV complexes: clathrin light chain (McCLC) and subunits µ1 and µ2 of the adaptor protein (AP) complex (McAP1µ and McAP2µ). Co-localization analyses revealed the association between McPIP1;4 and McAP2µ and between McPIP2;1 and McAP1µ, observations corroborated by mbSUS assays, suggesting that AQP abundance at the PM is under the control of CCV. The ability of McPIP1;4 and McPIP2;1 to form homo- and hetero-oligomers was tested and confirmed, as well as their activity as water channels. Also, we found increased phosphorylation of McPIP2;1 only at the PM in response to salt stress. Our results indicate root PIPs from halophytes might be regulated through CCV trafficking and phosphorylation, impacting their localization, transport activity, and abundance under salinity conditions.
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Acuaporinas , Mesembryanthemum , Vesículas Cubiertas por Clatrina , Mesembryanthemum/genética , Hielo , Membrana Celular/metabolismo , Proteínas de la Membrana/metabolismo , Estrés Salino , Plantas Tolerantes a la Sal/metabolismo , Acuaporinas/genética , Acuaporinas/metabolismo , Raíces de Plantas/genética , Raíces de Plantas/metabolismoRESUMEN
The treatment of spinal pathologies has evolved significantly from the times of Hippocrates and Galen to the current era. This evolution has led to the development of cutting-edge technologies to improve surgical techniques and patient outcomes. The University of Missouri Health System is a high-volume, tertiary care academic medical center that serves a large catchment area in central Missouri and beyond. The Department of Neurosurgery has sought to integrate the best available technologies to serve their spine patients. These technological advancements include intra-operative image guidance, robotic spine surgery, minimally invasive techniques, motion preservation surgery, and interdisciplinary care of metastatic disease to the spine. These advances have resulted in safer surgeries with enhanced outcomes at the University of Missouri. This integration of innovation demonstrates our tireless commitment to ensuring excellence in the comprehensive care of a diverse range of patients with complex spinal pathologies.
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Enfermedades de la Columna Vertebral , Humanos , Missouri , Enfermedades de la Columna Vertebral/cirugía , Centros Médicos Académicos/organización & administración , Procedimientos Quirúrgicos Mínimamente Invasivos/métodos , Procedimientos Neuroquirúrgicos/métodos , Procedimientos Quirúrgicos Robotizados/métodos , Procedimientos Quirúrgicos Robotizados/tendencias , Columna Vertebral/cirugíaRESUMEN
Ethanol fermentations can be prematurely halted as Saccharomyces cerevisiae faces adverse conditions, such as acidic pH, presence of acetic acid, and supraoptimal temperatures. The knowledge on yeast responses to these conditions is essential to endowing a tolerant phenotype to another strain by targeted genetic manipulation. In this study, physiological and whole-genome analyses were conducted to obtain insights on molecular responses which potentially render yeast tolerant towards thermoacidic conditions. To this end, we used thermotolerant TTY23, acid tolerant AT22, and thermo-acid tolerant TAT12 strains previously generated by adaptive laboratory evolution (ALE) experiments. The results showed an increase in thermoacidic profiles in the tolerant strains. The whole-genome sequence revealed the importance of genes related to: H+, iron, and glycerol transport (i.e., PMA1, FRE1/2, JEN1, VMA2, VCX1, KHA1, AQY3, and ATO2); transcriptional regulation of stress responses to drugs, reactive oxygen species and heat-shock (i.e., HSF1, SKN7, BAS1, HFI1, and WAR1); and adjustments of fermentative growth and stress responses by glucose signaling pathways (i.e., ACS1, GPA1/2, RAS2, IRA2, and REG1). At 30 °C and pH 5.5, more than a thousand differentially expressed genes (DEGs) were identified in each strain. The integration of results revealed that evolved strains adjust their intracellular pH by H+ and acetic acid transport, modify their metabolism and stress responses via glucose signaling pathways, control of cellular ATP pools by regulating translation and de novo synthesis of nucleotides, and direct the synthesis, folding and rescue of proteins throughout the heat-shock stress response. Moreover, the motifs analysis in mutated transcription factors suggested a significant association of SFP1, YRR1, BAS1, HFI1, HSF1, and SKN7 TFs with DEGs found in thermoacidic tolerant yeast strains. KEY POINTS: ⢠All the evolved strains overexpressed the plasma membrane H+ -ATPase PMA1 at optimal conditions ⢠Tolerant strain TAT12 mutated genes encoding weak acid and heat response TFs HSF1, SKN7, and WAR1 ⢠TFs HSF1 and SKN7 likely controlled the transcription of metabolic genes associated to heat and acid tolerance.
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Proteínas de Saccharomyces cerevisiae , ATPasas de Translocación de Protón Vacuolares , Saccharomyces cerevisiae/metabolismo , Temperatura , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Ácido Acético/metabolismo , Glucosa/metabolismo , Concentración de Iones de Hidrógeno , Proteínas de la Membrana/metabolismo , Proteína Fosfatasa 1/metabolismo , Transactivadores/metabolismo , ATPasas de Translocación de Protón Vacuolares/metabolismoRESUMEN
The export of membrane proteins along the secretory pathway is initiated at the endoplasmic reticulum after proteins are folded and packaged inside this organelle by their recruiting into the coat complex COPII vesicles. It is proposed that cargo receptors are required for the correct transport of proteins to its target membrane, however, little is known about ER export signals for cargo receptors. Erv14/Cornichon belong to a well conserved protein family in Eukaryotes, and have been proposed to function as cargo receptors for many transmembrane proteins. Amino acid sequence alignment showed the presence of a conserved acidic motif in the C-terminal in homologues from plants and yeast. Here, we demonstrate that mutation of the C-terminal acidic motif from ScErv14 or OsCNIH1, did not alter the localization of these cargo receptors, however it modified the proper targeting of the plasma membrane transporters Nha1p, Pdr12p and Qdr2p. Our results suggest that mistargeting of these plasma membrane proteins is a consequence of a weaker interaction between the cargo receptor and cargo proteins caused by the mutation of the C-terminal acidic motif.
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Secuencias de Aminoácidos/genética , Membrana Celular/genética , Proteínas de la Membrana/genética , Proteínas de Saccharomyces cerevisiae/genética , Transportadoras de Casetes de Unión a ATP/genética , Secuencia de Aminoácidos/genética , Vesículas Cubiertas por Proteínas de Revestimiento/genética , Vesículas Cubiertas por Proteínas de Revestimiento/metabolismo , Membrana Celular/metabolismo , Retículo Endoplásmico/genética , Retículo Endoplásmico/metabolismo , Aparato de Golgi/genética , Aparato de Golgi/metabolismo , Proteínas de la Membrana/metabolismo , Proteínas de Transporte de Membrana/genética , Oryza/genética , Pliegue de Proteína , Transporte de Proteínas/genética , Saccharomyces cerevisiae/genética , Alineación de Secuencia , Intercambiadores de Sodio-Hidrógeno/genéticaRESUMEN
The yeast Nha1p Na(+), K(+)/H(+) antiporter has a house-keeping role in pH and cation homeostasis. It is also needed to alleviate excess Na(+) or K(+) from the cytoplasm under high external concentrations of these cations. Erv14p, a putative cargo receptor for transmembrane proteins is required for trafficking of Nha1p from the endoplasmic reticulum to the plasma membrane. Sensitivity to high Na(+) concentrations of the erv14 mutant associated to the intracellular mislocalization of Nha1p-GFP, together with a lower Na(+) efflux, indicate the involvement of this mutual association to accomplish the survival of the yeast cell upon sodium stress. This observation is supported by the protein-protein interaction between Erv14p and Nha1p detected by the mating-based Split Ubiquitin System and co-immunoprecipitation assays. Our results indicate that even though Erv14p interacts with Nha1p through the TMD, the C-terminal is important not only for the efficient delivery of Nha1p to the plasma membrane but also for its dimerization to accomplish its role in yeast salt tolerance.
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Proteínas de Transporte de Catión/química , Regulación Fúngica de la Expresión Génica , Proteínas de la Membrana/química , Potasio/metabolismo , Protones , Proteínas de Saccharomyces cerevisiae/química , Saccharomyces cerevisiae/metabolismo , Cloruro de Sodio/metabolismo , Intercambiadores de Sodio-Hidrógeno/química , Transporte Biológico , Proteínas de Transporte de Catión/genética , Proteínas de Transporte de Catión/metabolismo , Cationes Monovalentes , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Potasio/farmacología , Unión Proteica , Dominios y Motivos de Interacción de Proteínas , Multimerización de Proteína , Estructura Secundaria de Proteína , Proteínas Recombinantes de Fusión/química , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , Saccharomyces cerevisiae/efectos de los fármacos , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Tolerancia a la Sal , Cloruro de Sodio/farmacología , Intercambiadores de Sodio-Hidrógeno/genética , Intercambiadores de Sodio-Hidrógeno/metabolismoRESUMEN
MAIN CONCLUSION: Tobacco germinated and grew in the presence of high concentrations of cadmium and zinc without toxic symptoms. Evidence suggests that these ions are sequestered into the vacuole by heavy metal/H + exchanger mechanisms. Heavy metal hyperaccumulation and hypertolerance are traits shared by a small set of plants which show specialized physiological and molecular adaptations allowing them to accumulate and sequester toxic metal ions. Nicotiana tabacum was used to test its potential as a metal-accumulator in a glass house experiment. Seed germination was not affected in the presence of increasing concentrations of zinc and cadmium. Juvenile and adult plants could concentrate CdCl2 and ZnSO4 to levels exceeding those in the hydroponic growth medium and maintained or increased their leaf dry weight when treated with 0.5- or 1-mM CdCl2 or 1-mM ZnSO4 for 5 days. Accumulation of heavy metals did not affect the chlorophyll and carotenoid levels, while variable effects were observed in cell sap osmolarity. Heavy metal-dependent H+ transport across the vacuole membrane was monitored using quinacrine fluorescence quenching. Cadmium- or zinc-dependent fluorescence recovery revealed that increasing concentrations of heavy metals stimulated the activities of the tonoplast Cd2+ or Zn2+/H+ exchangers. Immunodetection of the V-ATPase subunits showed that the increased proton transport by zinc was not due to changes in protein amount. MTP1 and MTP4 immunodetection and semiquantitative RT-PCR of NtMTP1, NtNRAMP1, and NtZIP1 helped to identify the genes that are likely involved in sequestration of cadmium and zinc in the leaf and root tissue. Finally, we demonstrated that cadmium and zinc treatments induced an accumulation of zinc in leaf tissues. This study shows that N. tabacum possesses a hyperaccumulation response, and thus could be used for phytoremediation purposes.
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Antiportadores/metabolismo , Cadmio/farmacología , Nicotiana/fisiología , Proteínas de Plantas/metabolismo , Zinc/farmacología , Adaptación Fisiológica , Cadmio/metabolismo , Cloruro de Cadmio/farmacología , Carotenoides/metabolismo , Clorofila/metabolismo , Electroforesis en Gel de Poliacrilamida , Germinación/efectos de los fármacos , Immunoblotting , Metales Pesados/metabolismo , Hojas de la Planta/metabolismo , Reacción en Cadena de la Polimerasa , Nicotiana/efectos de los fármacos , Nicotiana/metabolismo , Vacuolas/metabolismo , Zinc/metabolismo , Sulfato de Zinc/farmacologíaRESUMEN
Membrane proteins are synthesized and folded in the endoplasmic reticulum (ER), and continue their path to their site of residence along the secretory pathway. The COPII system has been identified as a key player for selecting and directing the fate of membrane and secretory cargo proteins. Selection of cargo proteins within the COPII vesicles is achieved by cargo receptors. The cornichon cargo receptor belongs to a conserved protein family found in eukaryotes that has been demonstrated to participate in the selection of integral membrane proteins as cargo for their correct targeting. Here it is demonstrated at the cellular level that rice cornichon OsCNIH1 interacts with OsHKT1;3 and, in yeast cells, enables the expression of the sodium transporter to the Golgi apparatus. Physical and functional HKT-cornichon interactions are confirmed by the mating-based split ubiquitin system, bimolecular fluorescence complementation, and Xenopus oocyte and yeast expression systems. The interaction between the two proteins occurs in the ER of plant cells and their co-expression in oocytes leads to the sequestration of the transporter in the ER. In the yeast cornichon mutant erv14, OsHKT1;3 is mistargeted, preventing the toxic effects of sodium transport in the cell observed in wild-type cells or in the erv14 mutant that co-expressed OsHKT1;3 with either OsCNIH1 or Erv14p. Identification and characterization of rice cornichon as a possible cargo receptor opens up the opportunity to improve our knowledge on membrane protein targeting in plant cells.
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Proteínas de Transporte de Catión/metabolismo , Aparato de Golgi/metabolismo , Oryza/metabolismo , Proteínas de Plantas/fisiología , Secuencia de Aminoácidos , Animales , Transporte Biológico , Proteínas de Transporte de Catión/genética , Retículo Endoplásmico/metabolismo , Proteínas de Transporte de Membrana/genética , Proteínas de Transporte de Membrana/metabolismo , Proteínas de Transporte de Membrana/fisiología , Datos de Secuencia Molecular , Oryza/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Mapeo de Interacción de Proteínas , Alineación de Secuencia , Análisis de Secuencia de Proteína , Sodio/metabolismo , XenopusRESUMEN
Intradural disc herniations (IDH) account for 0.27% of all disc herniations. Cervical IDH account for 3% of these, with only 47 cases reported in the literature, making it an extremely rare diagnosis. Brown-Séquard syndrome is the most common presentation of cervical IDH. Emergent decompression is usually necessary. We present the case of a 56-year-old woman who presented with Brown-Séquard syndrome secondary to a spontaneous intradural C5-6 disc herniation. A posterior transdural approach was recommended to arrest her neurological deficit and promote improvement. The patient consented to the procedure. Institutional Review Board approval was not necessary, given this treatment was necessary and indicated. A standard posterior cervical exposure and C5-6 laminectomies were performed. The dura was opened with a "peeling" technique. The compressive disc fragments were removed. A dural defect was identified along the C6 nerve root sleeve. Fluoroscopy was used to confirm the communication of the defect with the C5-6 disc space. A single 5-0 Prolene suture was used to repair the defect, approximating the anterior dura with a flap from the nerve root sleeve. The patient had an uneventful postoperative course. At 7-month follow-up, her neurological deficits had nearly resolved. Surgeons should consider IDH in the differential diagnosis for sudden neurologic decline in the setting of an intradural mass and should be familiar with the association between cervical IDH and Brown-Séquard syndrome. The posterior transdural approach provides excellent exposure, easier management of dural defects, and ability to handle a variety of intradural pathologies and may avoid the need for concomitant fusion.
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STUDY DESIGN: Retrospective Case-Series. OBJECTIVES: Due to heterogeneity in previous studies, the effect of MI-TLIF on postoperative segmental lordosis (SL) and lumbar lordosis (LL) remains unclear. Therefore, we aim to identify radiographic factors associated with lordosis after surgery in a homogenous series of MI-TLIF patients. METHODS: A single-center retrospective review identified consecutive patients who underwent single-level MI-TLIF for grade 1 degenerative spondylolisthesis from 2015-2020. All surgeries underwent unilateral facetectomies and a contralateral facet release with expandable interbody cages. PROs included the ODI and NRS-BP for low-back pain. Radiographic measures included SL, disc height, percent spondylolisthesis, cage positioning, LL, PI-LL mismatch, sacral-slope, and pelvic-tilt. Surgeries were considered "lordosing" if the change in postoperative SL was ≥ +4° and "kyphosing" if ≤ -4°. Predictors of change in SL/LL were evaluated using Pearson's correlation and multivariable regression. RESULTS: A total of 73 patients with an average follow-up of 22.5 (range 12-61) months were included. Patients experienced significant improvements in ODI (29% ± 22% improvement, P < .001) and NRS-BP (3.3 ± 3 point improvement, P < .001). There was a significant increase in mean SL (Δ3.43° ± 4.37°, P < .001) while LL (Δ0.17° ± 6.98°, P > .05) remained stable. Thirty-eight (52%) patients experienced lordosing MI-TLIFs, compared to 4 (5%) kyphosing and 31 (43%) neutral MI-TLIFs. A lower preoperative SL and more anterior cage placement were associated with the greatest improvement in SL (ß = -.45° P = .001, ß = 15.06° P < .001, respectively). CONCLUSIONS: In our series, the majority of patients experienced lordosing or neutral MI-TLIFs (n = 69, 95%). Preoperative radiographic alignment and anterior cage placement were significantly associated with target SL following MI-TLIF.
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BACKGROUND: Despite an increased understanding of the impact of socioeconomic status on neurosurgical outcomes, the impact of neighborhood-level social determinants on lumbar spine surgery patient-reported outcomes remains unknown. OBJECTIVE: To evaluate the impact of geographic social deprivation on physical and mental health of lumbar surgery patients. METHODS: A single-center retrospective cohort study analyzing patients undergoing lumbar surgery for degenerative disease from 2015 to 2018 was performed. Surgeries were categorized as decompression only or decompression with fusion. The area deprivation index was used to define social deprivation. Study outcomes included preoperative and change in Patient-Reported Outcomes Measurement (PROMIS) physical function (PF), pain interference (PI), depression, and anxiety (mean follow-up: 43.3 weeks). Multivariable imputation was performed for missing data. One-way analysis of variance and multivariable linear regression were used to evaluate the association between area deprivation index and PROMIS scores. RESULTS: In our cohort of 2010 patients, those with the greatest social deprivation had significantly worse mean preoperative PROMIS scores compared with the least-deprived cohort (mean difference [95% CI]-PF: -2.5 [-3.7 to -1.4]; PI: 3.0 [2.0-4.1]; depression: 5.5 [3.4-7.5]; anxiety: 6.0 [3.8-8.2], all P < .001), without significant differences in change in these domains at latest follow-up (PF: +0.5 [-1.2 to 2.2]; PI: -0.2 [-1.7 to 2.1]; depression: -2 [-4.0 to 0.1]; anxiety: -2.6 [-4.9 to 0.4], all P > .05). CONCLUSION: Lumbar spine surgery patients with greater social deprivation present with worse preoperative physical and mental health but experience comparable benefit from surgery than patients with less deprivation, emphasizing the need to further understand social and health factors that may affect both disease severity and access to care.
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Medición de Resultados Informados por el Paciente , Disparidades Socioeconómicas en Salud , Humanos , Estudios Retrospectivos , Procedimientos Neuroquirúrgicos , Región Lumbosacra/cirugíaRESUMEN
BACKGROUND CONTEXT: Patients with cervical spine disease suffer from upper limb disability. At present, no clinical benchmarks exist for clinically meaningful change in the upper limb function following cervical spine surgery. PURPOSE: Primary: to establish clinically meaningful metrics; the minimal clinically important difference (MCID) and substantial clinical benefit (SCB) of upper limb functional improvement in patients following cervical spine surgery. Secondary: to identify the prognostic factors of MCID and SCB of upper limb function following cervical spine surgery. STUDY DESIGN: Retrospective cohort study. PATIENT SAMPLE: Adult patients ≥18 years of age who underwent cervical spine surgery from 2012 to 2016. OUTCOME MEASURES: Patient-reported outcomes: Neck disability index (NDI) and Disabilities of Arm, Shoulder, and Hand (DASH). METHODS: MCID was defined as minimal improvement and SCB as substantial improvement in the DASH score at last follow-up. The anchor-based methods (ROC analyses) defined optimal MCID and SCB thresholds with area under curve (AUC) in discriminating improved vs. non-improved patients. The MCID was also calculated by distribution-based methods: half standard-deviation (0.5-SD) and standard error of the mean (SEM) method. A multivariable logistic regression evaluated the impact of baseline factors in achieving the MCID and SCB in DASH following cervical spine surgery. RESULTS: Between 2012 and 2016, 1,046 patients with average age of 57±11.3 years, 53% males, underwent cervical spine surgery. Using the ROC analysis, the threshold for MCID was -8 points with AUC of 0.73 (95% CI: 0.67-0.79) and the SCB was -18 points with AUC of 0.88 (95% confidence interval [CI]: 0.85-0.91). The MCID was -11 points by 0.5-SD and -12 points by SEM-method. On multivariable analysis, patients with myelopathy had lower odds of achieving MCID and SCB, whereas older patients and those with ≥6 months duration of symptoms had lower odds of achieving DASH MCID and SCB respectively. CONCLUSIONS: In patients undergoing cervical spine surgery, MCID of -8 points and SCB of -18 points in DASH improvement may be considered clinically significant. These metrics may enable evaluation of minimal and substantial improvement in the upper extremity function following cervical spine surgery.
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Brazo , Hombro , Adulto , Masculino , Humanos , Persona de Mediana Edad , Anciano , Femenino , Hombro/cirugía , Estudios Retrospectivos , Resultado del Tratamiento , Extremidad Superior , Vértebras Cervicales/cirugíaRESUMEN
BACKGROUND: Rapid growth in smartphone use has expanded opportunities to use mobile health (mHealth) technology to collect real-time patient-reported and objective biometric data. These data may have important implication for personalized treatments of degenerative spine disease. However, no large-scale study has examined the feasibility and acceptability of these methods in spine surgery patients. OBJECTIVE: To evaluate the feasibility and acceptability of a multimodal preoperative mHealth assessment in patients with degenerative spine disease. METHODS: Adults undergoing elective spine surgery were provided with Fitbit trackers and sent preoperative ecological momentary assessments (EMAs) assessing pain, disability, mood, and catastrophizing 5 times daily for 3 weeks. Objective adherence rates and a subjective acceptability survey were used to evaluate feasibility of these methods. RESULTS: The 77 included participants completed an average of 82 EMAs each, with an average completion rate of 86%. Younger age and chronic pulmonary disease were significantly associated with lower EMA adherence. Seventy-two (93%) participants completed Fitbit monitoring and wore the Fitbits for an average of 247 hours each. On average, participants wore the Fitbits for at least 12 hours per day for 15 days. Only worse mood scores were independently associated with lower Fitbit adherence. Most participants endorsed positive experiences with the study protocol, including 91% who said they would be willing to complete EMAs to improve their preoperative surgical guidance. CONCLUSION: Spine fusion candidates successfully completed a preoperative multimodal mHealth assessment with high acceptability. The intensive longitudinal data collected may provide new insights that improve patient selection and treatment guidance.
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Teléfono Inteligente , Telemedicina , Adulto , Humanos , Estudios de Factibilidad , Encuestas y Cuestionarios , Evaluación Ecológica MomentáneaRESUMEN
OBJECTIVE: We present a single-institution case series of patients who experienced pharyngoesophageal damage, specifically from extruded hardware occurring at an average of 7.5 years after anterior cervical diskectomy and fusion (ACDF). METHODS: A retrospective chart review was conducted of patients who had undergone ACDF with subsequent delayed pharyngoesophageal perforation or erosion from extruded hardware ≥1 year after surgery. A discussion of the literature surrounding this complication, including risk factors and management, is also presented. RESULTS: Nine patients were identified (average age 58 years, 66.7% male) among a total of 4122 ACDF patients (incidence: 0.22%). Average time to injury was 7.5 years. Indications for initial ACDF were degenerative cervical disease (n = 7), ankylosing spondylitis (n = 1), and cervical fracture (n = 1). Eight patients had prior multilevel ACDF spanning 2 (n = 4), 3 (n = 1), or 4 levels (n = 2). Fusion levels for prior ACDF included C5-C7 (n = 3), C3-C7 (n = 2), C4-C7 (n = 1), C4-C6 (n = 1), C2-C5 (n = 1), and C6-C7 (n = 1). Pharyngoesophageal injuries included esophageal perforation (n = 3), pharyngeal perforation (n = 2), esophageal erosion (n = 3), and pharyngoesophageal erosion (n = 1). In most (n = 6) cases, the cause of pharyngoesophageal damage was due to ≥1 extruded screws. Dysphagia (n = 8) was the most common presenting symptom. For perforations (n = 5), 2 repairs used a rotational flap to reinforce a primary closure; the other 3 cases were repaired via primary closure. CONCLUSIONS: Pharyngoesophageal damage caused by extruded hardware may occur several years after ACDF. These delayed complications are difficult to predict. Proper screw placement may be the most important factor for minimizing the chances of this potentially devastating complication, particularly with multilevel constructs.
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Trastornos de Deglución , Fusión Vertebral , Vértebras Cervicales/cirugía , Trastornos de Deglución/etiología , Discectomía/efectos adversos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo , Fusión Vertebral/efectos adversosRESUMEN
OBJECTIVE: Local and regional radiographic outcomes following minimally invasive (MI) transforaminal lumbar interbody fusion (TLIF) versus open TLIF remain unclear. The purpose of this study was to provide a comprehensive assessment of local and regional radiographic parameters following MI-TLIF and open TLIF. The authors hypothesized that open TLIF provides greater segmental and global lordosis correction than MI-TLIF. METHODS: A single-center retrospective cohort study of consecutive patients undergoing MI- or open TLIF for grade I degenerative spondylolisthesis was performed. One-to-one nearest-neighbor propensity score matching (PSM) was used to match patients who underwent open TLIF to those who underwent MI-TLIF. Sagittal segmental radiographic measures included segmental lordosis (SL), anterior disc height (ADH), posterior disc height (PDH), foraminal height (FH), percent spondylolisthesis, and cage position. Lumbopelvic radiographic parameters included overall lumbar lordosis (LL), pelvic incidence (PI)-lumbar lordosis (PI-LL) mismatch, sacral slope (SS), and pelvic tilt (PT). Change in segmental or overall lordosis after surgery was considered "lordosing" if the change was > 0° and "kyphosing" if it was ≤ 0°. Student t-tests or Wilcoxon rank-sum tests were used to compare outcomes between MI-TLIF and open-TLIF groups. RESULTS: A total of 267 patients were included in the study, 114 (43%) who underwent MI-TLIF and 153 (57%) who underwent open TLIF, with an average follow-up of 56.6 weeks (SD 23.5 weeks). After PSM, there were 75 patients in each group. At the latest follow-up both MI- and open-TLIF patients experienced significant improvements in assessment scores obtained with the Oswestry Disability Index (ODI) and the numeric rating scale for low-back pain (NRS-BP), without significant differences between groups (p > 0.05). Both MI- and open-TLIF patients experienced significant improvements in SL, ADH, and percent corrected spondylolisthesis compared to baseline (p < 0.001). However, the MI-TLIF group experienced significantly larger magnitudes of correction with respect to these metrics (ΔSL 4.14° ± 4.35° vs 1.15° ± 3.88°, p < 0.001; ΔADH 4.25 ± 3.68 vs 1.41 ± 3.77 mm, p < 0.001; percent corrected spondylolisthesis: -10.82% ± 6.47% vs -5.87% ± 8.32%, p < 0.001). In the MI-TLIF group, LL improved in 44% (0.3° ± 8.5°) of the cases, compared to 48% (0.9° ± 6.4°) of the cases in the open-TLIF group (p > 0.05). Stratification by operative technique (unilateral vs bilateral facetectomy) and by interbody device (static vs expandable) did not yield statistically significant differences (p > 0.05). CONCLUSIONS: Both MI- and open-TLIF patients experienced significant improvements in patient-reported outcome (PRO) measures and local radiographic parameters, with neutral effects on regional alignment. Surprisingly, in our cohort, change in SL was significantly greater in MI-TLIF patients, perhaps reflecting the effect of operative techniques, technological innovations, and the preservation of the posterior tension band. Taking these results together, no significant overall differences in LL between groups were demonstrated, which suggests that MI-TLIF is comparable to open approaches in providing radiographic correction after surgery. These findings suggest that alignment targets can be achieved by either MI- or open-TLIF approaches, highlighting the importance of surgeon attention to these variables.
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OBJECTIVE: Intraoperative magnetic resonance imaging (ioMRI) provides immediate feedback and quality assurance enabling the neurosurgeon to improve the quality of a range of neurosurgical procedures. Implementation of ioMRI is a complex and costly process. We describe our preliminary 16 months experience with the integration of an IMRIS movable ceiling mounted high field (1.5 T) ioMRI setup with two operating rooms. METHODS: Aspects of implementation of our ioMRI and our initial 16 months of clinical experience in 180 consecutive patients were reviewed. RESULTS: The installation of a ceiling mounted movable ioMRI between two operating rooms was completed in April 2008 at Barnes-Jewish Hospital in St. Louis. Experience with 180 neurosurgical cases (M:F-100:80, age range 1-79 years, 71 gliomas, 57 pituitary adenomas, 9 metastases, 11 other tumor cases, 4 Chiari decompressions, 6 epilepsy resections and 22 other miscellaneous procedures) demonstrated that this device effectively provided high quality real-time intraoperative imaging. In 74 of all 180 cases (41%) and in 54% of glioma resections, the surgeon modified the procedure based upon the ioMRI. Ninety-three percent of ioMRI glioma cases achieved gross/near total resection compared to 65% of non ioMRI glioma cases in this time frame. CONCLUSION: A movable high field strength ioMRI can be safely integrated between two neurosurgical operating rooms. This strategy leads to modification of the surgical procedure in a significant number of cases, particularly for glioma surgery. Long-term follow up is needed to evaluate the clinical and financial impact of this technology in the field of neurosurgery.
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Neoplasias Encefálicas/cirugía , Glioma/cirugía , Imagen por Resonancia Magnética/instrumentación , Imagen por Resonancia Magnética/métodos , Neurocirugia/instrumentación , Quirófanos , Adolescente , Adulto , Anciano , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Persona de Mediana Edad , Neurocirugia/métodos , Estudios Prospectivos , Estudios Retrospectivos , Adulto JovenRESUMEN
OBJECTIVE: To determine the characteristics of the Puerto Rico Veteran population with iron overload in terms of demographic features, clinical manifestations, and the presence of hereditary hemochromatosis (HH) mutations, and to compare such characteristics in patients with and without HH mutations. METHODS: A retrospective study was conducted in patients with iron overload (transferrin saturation > or = 45%) who were tested for HH mutations from January 2003 to June 2007. Data collected included age, gender, body mass index, hemoglobin level, platelet count, ferritin level, transferrin saturation, ceruloplasmin, alfa-1 antitrypsin, anti-nuclear antibodies, aspartate aminotransferase, alanine aminotransferase, alfa-fetoprotein, viral hepatitis profile, imaging studies, and comorbid conditions. Patients were grouped according to the results of the commercially available HH DNA mutation analysis as homozygote, heterozygote, compound heterozygote, or negative. RESULTS: 94 patients were studied. Most patients were male (90/94); the mean age was 60 years. Of the study group, 36% (34/94) was found positive for HH mutations. The most common mutation was H63D, which was found in 85% (29/34) of patients; 4 homozygotes and 25 heterozygotes. C282Y mutation was identified in only 12% (4/34) of patients, of which one was homozygote. A compound heterozygote (C282Y/ H63D) was also identified. After analyzing the data for confounding factors, 6 of 29 heterozygotes had no other risk factors for liver disease other than the H63D mutation. CONCLUSION: The predominance of H63D mutations in our population deserves further investigation since it considerably differs from other studied populations with iron overload in which C282Y is the most common mutation.
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Hemocromatosis/complicaciones , Hemocromatosis/genética , Hispánicos o Latinos/genética , Sobrecarga de Hierro/complicaciones , Mutación , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios RetrospectivosRESUMEN
BACKGROUND: Frontal sinus cranialization with closure via bifrontal pericranial flaps is the gold standard for separating the nasofrontal recess from the intracranial cavity for posterior table defects. Despite the high success rate, cerebrospinal fluid (CSF) leak may persist and is particularly challenging when vascularized reconstructive options from the bicoronal incision are exhausted. OBJECTIVE: To assess a novel endonasal technique using an adipofascial radial forearm free flap delivered to the frontal recess through a Draf sinusotomy to repair complex CSF leaks from the frontal sinus. METHODS: A retrospective review of 3 patients (all male; ages 42, 43, and 69 yr) with persistent CSF leak despite frontal sinus cranialization and repair with bifrontal pericranium was performed. Etiology of injury was traumatic in 2 patients and iatrogenic in 1 patient after anaplastic meningioma treatment. To create space for the flap and repair the nasofrontal ducts, endoscopic Draf III (Case 1, 3) or Draf IIb left frontal sinusotomy (Case 2) was performed. The forearm flap was harvested, passed through a Caldwell-Luc exposure, and placed within the Draf frontal sinustomy. The flap vessels were tunneled to the left neck and anastomosed to the facial vessels by the mandibular notch. RESULTS: Intraoperatively, the flaps were well-seated and provided a watertight seal. Postoperative hospital courses were uncomplicated. There were no new CSF leaks or flap necrosis at 12, 14, and 16 mo. CONCLUSION: Endoscopic endonasal free flap reconstruction through a Draf procedure is a novel viable option for persistent CSF leak after failed frontal sinus cranialization.
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Colgajos Tisulares Libres , Seno Frontal , Procedimientos de Cirugía Plástica , Pérdida de Líquido Cefalorraquídeo/etiología , Pérdida de Líquido Cefalorraquídeo/cirugía , Colgajos Tisulares Libres/cirugía , Seno Frontal/cirugía , Humanos , Masculino , Procedimientos de Cirugía Plástica/métodos , Base del Cráneo/cirugíaRESUMEN
The moss Physcomitrium (Physcomitrella) patens is a bryophyte that provides genetic information about the adaptation to the life on land by early Embryophytes and is a reference organism for comparative evolutionary studies in plants. Copper is an essential micronutrient for every living organism, its transport across the plasma membrane is achieved by the copper transport protein family COPT/CTR. Two genes related to the COPT family were identified in Physcomitrella patens, PpaCOPT1 and PpaCOPT2. Homology modelling of both proteins showed the presence of three putative transmembrane domains (TMD) and the Mx3M motif, constituting a potential Cu + selectivity filter present in other members of this family. Functional characterization of PpaCOPT1 and PpaCOPT2 in the yeast mutant ctr1Δctr3Δ restored its growth on medium with non-fermentable carbon sources at micromolar Cu concentrations, providing support that these two moss proteins function as high affinity Cu + transporters. Localization of PpaCOPT1 and PpaCOPT2 in yeast cells was observed at the tonoplast and plasma membrane, respectively. The heterologous expression of PpaCOPT2 in tobacco epidermal cells co-localized with the plasma membrane marker. Finally, only PpaCOPT1 was expressed in seven-day old protonema and was influenced by extracellular copper levels. This evidence suggests different roles of PpaCOPT1 and PpaCOPT2 in copper homeostasis in Physcomitrella patens.
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Bryopsida , Secuencia de Aminoácidos , Bryopsida/genética , Bryopsida/metabolismo , Cobre/metabolismo , Proteínas Transportadoras de Cobre , HomeostasisRESUMEN
OBJECTIVE: Short-term benefits of achieving sustained virologic response (SVR) to treatment for hepatitis C virus infection (HCV) have been well established. However long-term data on benefits of achieving SVR has just begun to emerge. The purpose of this study was to determine whether SVR truly represents long- term viral eradication in a Latino veteran population and document clinical and biochemical outcomes in this group. METHODS: This was a two-phase study, which consisted of a single center retrospective study followed by a cross-sectional analysis which includes a single clinic visit. The first phase of the study consisted of a retrospective record review of all HCV patients treated at the VA Caribbean Healthcare System from 1990 to 2006. Records were reviewed to identify patients who had completed therapy, had documented SVR and at least 12 months of time elapsed since end of therapy. The second phase of the study entailed a single appointment to the gastroenterology research clinics, for blood testing and a short risk factor questionnaire. RESULTS: Sixty four patients were enrolled; mostly males with a mean age at time of enrollment of 54.3 years (range 37-72). One hundred percent of subjects self reported their ethnicity as Hispanic, born in Puerto Rico. Most of our population had HCV genotype 1. Forty seven of 64 (73.4%) patients were naive to therapy while 4 (6.3%) were previously treated. In 13 (20.3%) patients, the prior treatment status could not be clearly established. Regarding therapy used to achieve SVR, 32 (50.0%) patients received interferon (IFN) and ribavarin, 28 (43.8%) peginterferon (PEG) and ribavarin and 4 (6.3%) IFN monotherapy. There was no statistical difference in long-term SVR among these 3 three treatment alternatives. A pre-treatment biopsy specimen was available on 37/64 (57.8%) of our subjects. Marked fibrosis and/or cirrhosis was present in 14/37 (37.8%) subjects who had a pre-treatment biopsy. At the time of the study visit mild elevation of aspartate aminotransferase (AST) was identified only in 5 (7.8%) patients. Alanine aminotransferase (ALT) and bilirubin were normal. Only 3/64 (4.7%) had elevations in alkaline phosphatase. None (0/58) of the patients who presented with normal enzymes had detectable viral load, whereas 20% (1/5) of those with elevated liver function tests had evidence of viremia (p < 0.001). Overall, only 1 (1.6%) patient of our study group had evidence of virological relapse after having achieved SVR, which was documented 30 months after the end of therapy. No identifiable risk factors for re-infection were identified. CONCLUSION: In conclusion, in this Latino veteran population, achievement of (SVR) is a good predictor of clinical outcomes and long-term (HCV) eradication. Altered liver function tests seems to be the best predictor of relapse and should prompt the clinician to investigate for recurrence. For those that after achieving SVR maintain normal liver enzymes, routine follow up viral load demonstrates to have a very low yield and may not be required.
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Antivirales/uso terapéutico , Hepatitis C Crónica/tratamiento farmacológico , Hispánicos o Latinos , Veteranos , Adulto , Anciano , Estudios Transversales , Femenino , Hepatitis C Crónica/virología , Humanos , Masculino , Persona de Mediana Edad , Inducción de Remisión , Estudios Retrospectivos , Factores de TiempoRESUMEN
STUDY DESIGN: Retrospective cohort study. OBJECTIVE: The Metastatic Spine Disease Multidisciplinary Working Group Algorithms are evidence and expert opinion-based strategies for utilizing radiation therapy, interventional radiology procedures, and surgery to treat 5 types of spine metastases: asymptomatic spinal metastases, uncomplicated spinal metastases, stable vertebral compression fractures (VCF), unstable VCF, and metastatic epidural spinal cord compression (MESCC). Evaluation of this set of algorithms in a clinical setting is lacking. The authors aimed to identify rate of treatment adherence to the Working Group Algorithms and, subsequently, update these algorithms based on actual patient management decisions made at a single-institution, multidisciplinary, spine tumor conference. METHODS: Patients with metastatic spine disease from primary non-hematologic malignancies discussed at an institutional spine tumor conference from 2013 to 2016 were evaluated. Rates of Working Group Algorithms adherence were calculated for each type of metastasis. Based on the reasons for algorithm nonadherence, and patient outcomes in such cases, updated Working Group Algorithms recommendations were proposed. RESULTS: In total, 154 eligible patients with 171 spine metastases were evaluated. Rates of algorithm adherence were as follows: asymptomatic (67%), uncomplicated (73%), stable VCF (20%), unstable VCF (32%), and MESCC (41%). The most common deviation from the Working Group Algorithms was surgery for MESCC despite poor prognostic factors, but this treatment strategy was supported based on median survival surpassing 6 months in these patients. CONCLUSIONS: Adherence to the Working Group Algorithm was lowest for MESCC and VCF patients, but many nonadherent treatments were supported by patient survival outcomes. We proposed updates to the Working Group Algorithm based on these findings.