Κυριακή, 11 Ιουνίου 2017

Comparison of a 2.0-mm locking system with conventional 2.0- and 2.4-mm systems in the treatment of mandibular fractures: a randomized controlled trial

Abstract

Purpose

A comparative study of the use of the 2.0-mm locking fixation system with conventional systems in the treatment of mandibular fractures was performed.

Methods

For this study, 87 consecutive patients with 112 mandibular fractures were randomized to receive either 2.0-mm locking plates (n = 45) or conventional 2.0- or 2.4-mm plates (n = 42) and had a minimum follow-up of 6 months. Fractures were classified based on the degree of displacement and complexity. Statistical analyses were used to verify possible differences between the groups when separately compared unfavourable and favourable cases (p ≤ 0.050).

Results

Despite randomization, systemic diseases were more frequent in the 2.0-mm locking group in favourable cases. Substance abuse occurred predominantly in the 2.0-mm locking group, in unfavourable and favourable fractures. There were more cases of complex fractures in the conventional group in unfavourable cases. One case involving a major postoperative complication occurred in the locking group (2.2%) and three cases occurred in the conventional group (7.1%) but with no significant difference between groups. In this study, there were no major differences between conventional and locking 2.0-mm locking systems with regard to the outcome of treated mandibular fractures, showing that both are adequate as long as the criteria of their indication and requirements for installation are met.

Conclusions

It was concluded that the 2.0-mm locking fixation system can replace conventional systems in the treatment of mandibular fractures; in addition, this approach was effective in the treatment of unfavourable fractures that typically require the 2.4-mm conventional system.



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Comment to: The Increased Cost of Ventral Herina Recurrence: A Cost Analysis Davila, D.G., Parikh, N., Frelich, M.J. et al. Herina (2016) 20:811



http://ift.tt/2tbnqFI

Reply to Comment to: The Increased Cost of Ventral Hernia Recurrence: A Cost Analysis Davila, D.G., Parikh, N., Frelich, M.J. et al. Hernia (2016) 20: 811



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Ponto 3 SuperPower, New Treatment Option to BAHS Patients

An overview of Ponto 3 superpower bone anchored hearing system, patient benefits, outcomes with its directionality system, and fitting aspects for professionals.

http://ift.tt/2r9GlQo

20Q: EMA Methodology - Research Findings and Clinical Potential

an overview of Ecological Momentary Assessment (EMA), its relevance to audiology research and practice, a review of key studies using this methodology, and a look at potential future applications.

http://ift.tt/2r9IjQU

Data Logging - Hearing Aid Behavior in the Real World

This course will examine the information available in the Starkey Inspire Data Log and applications for using that information to enhance the patient's journey with amplification.

http://ift.tt/2r9db4h

Transnasal endoscopic ultrasound-guided reduction of maxillary sinus wall fracture

Abstract

Surgical morbidity from open reduction and internal fixation (ORIF) of maxillary sinus wall fracture often surpasses the benefits of ORIF. Hence, the authors devised transnasal endoscopic-assisted reduction of maxillary sinus wall fracture (TERM) without internal fixation as a minimally invasive surgery for maxillary sinus wall fracture. The purpose of this study was to investigate the feasibility of TERM in cadavers and patients. Six cadavers were dissected to evaluate the feasibility of TERM. In addition, 20 patients with maxillary sinus wall fractures who underwent TERM in a tertiary hospital from August of 2013 to December of 2015 were enrolled in this study. Demographic factors, type of anesthesia, computed tomography (CT) scans, clinical characteristics of patients, and patient satisfaction with surgery were analyzed. Cadaveric study showed that endoscopic inferior meatus antrostomy is a feasible method of approaching the maxillary sinus wall in cadavers. In addition, counterforce could be applied to the maxillary sinus wall by pushing packed Vaseline-soaked gauze or using a zygomatic process approach via a Gillies incision. Clinical experience revealed that patients experienced good facial contour restoration postoperatively. The extent of fractured bony segments was reduced on postoperative CT without complications. Patient satisfaction with TERM was greater than that with ORIF (p = 0.031). TERM showed its feasibility in both cadaveric study and clinical study. TERM can be a good alternative to ORIF, especially in patients who are reluctant to undergo a facial incision.



from #AlexandrosSfakianakis via Alexandros G.Sfakianakis on Inoreader http://ift.tt/2rh3DYN
via IFTTT

Clinical evaluation of zirconia-based all-ceramic single crowns: an up to 12-year retrospective cohort study

Abstract

Objectives

This study aims to investigate the incidence of clinical complications with tooth-supported zirconia-based all-ceramic single crowns and identify pertinent risk parameters.

Materials and methods

A retrospective cohort study (May 2004 to April 2016) utilizing clinical records of patients receiving yttrium-oxide–partially stabilized zirconia (Y-TZP)-based all-ceramic crowns placed at Tohoku University Hospital was performed. The length of time of treatment success (complication event-free) and restoration survival (including minor complication events and remaining clinically functional) were estimated using Kaplan–Meier analysis. Multilevel survival analysis was used to identify risk factors.

Results

One hundred thirty-seven crowns were evaluated (mean follow-up time, 7.0 years). A total of 21 crowns experienced at least one complication with fracture of veneering ceramic being the most common (16 crowns). Estimated success and survival rates at 5 years (96.9 and 98.5%, respectively) decreased at 10 years to 62.1 and 67.2%, respectively. The risk of complications was significantly higher for molar crowns compared to anterior crowns (p < 0.01). A significant association of complications with metal antagonist restorations was shown by univariate analysis (p < 0.01).

Conclusions

Given the study limitations, Y-TZP single crowns placed on anterior teeth demonstrated encouraging clinical results over a period of up to 10 years. However, there is a substantial risk of complications with posterior teeth within 10 years of restoration placement.

Clinical relevance

Treatment with zirconia-based all-ceramic crowns for molar teeth with metal antagonist occlusion should be undertaken with caution.



http://ift.tt/2sdwOLJ

Craniofacial and dental characteristics of patients with vitamin-D-dependent rickets type 1A compared to controls and patients with X-linked hypophosphatemia

Abstract

ᅟObjectives

Vitamin-D-dependent rickets type 1A (VDDR1A) is a rare inherited disease caused by defective activation of vitamin D. The aim of the study was to describe the craniofacial characteristics and the dental phenotype of patients with genetically confirmed VDDR1A. The VDDR1A findings were compared to findings in patients with X-linked hypophosphatemia (XLH) and healthy controls.

Material and methods

Ten patients with VDDR1A were identified. The reference group for the comparison of cephalometric findings was 49 adults without chronic disease. The reference group for the comparison of dental findings was 30 adults with XLH. Clinical examination, clinical photos, and radiographs were obtained. Cephalometric analysis was performed. Photos and radiographs were visually evaluated.

Results

The depth of the posterior cranial fossa (d-p and d-s-iop) in VDDR1A adults was reduced compared to the reference group (p < 0.05). Five (83%) of six adults with VDDR1A and one (4%) of 25 adults with XLH had enamel hypoplasia on several incisors and/or canines (p < 0.001). Three (75%) of four adults with VDDR1A and none of 16 adults with XLH had several first molars with enamel hypoplasia (p = 0.004). Five of 7 (71%) adults with VDDR1A and 24 of 30 (80%) adults with XLH had endodontically affected teeth.

Conclusions

The dental aberration of VDDR1A is more in line with the dental aberration of nutritional rickets than with the dental aberrations in XLH, suggesting the combination of low availability of both calcium and phosphate to be critical in periods of enamel formation.

Clinical relevance

Knowledge on craniofacial and dental aberration in patients with rare diseases, e.g., inherited rickets, is of importance to the dental practitioner, especially during diagnostics and treatment in special care units.



http://ift.tt/2tboLwa

Coarctation Index Predicts Recurrent Aortic Arch Obstruction Following Surgical Repair of Coarctation of the Aorta in Infants

Abstract

Recurrent aortic arch obstruction (RAAO) remains a major cause of morbidity following surgical neonatal repair of coarctation of the aorta (CoA). Elucidating predictors of RAAO can identify high-risk patients and guide postoperative management. The Coarctation index (CoA-I), defined as the ratio of the diameter of the narrowest aortic arch segment to the diameter of the descending aorta, has been used to help diagnose RAAO in neonates following the Norwood Procedure. We sought to assess the predictive value of the CoA-I on RAAO after CoA repair in infants with biventricular circulation. Clinical, surgical, and echocardiographic data of infants with biventricular circulation following neonatal CoA repair between 2010 and 2014 were evaluated. RAAO was defined using a composite quantitative outcome variable: a blood pressure gradient >20, a peak aortic arch velocity >3.5 m/s by echocardiogram, or a catheter-measured peak-to-peak gradient >20 within 2 years of surgery. Univariate and multivariate logistic regression analyses were used. Of the 68 subjects included in the analysis, 15 (22%) met criteria for RAAO. In the multivariate model, only CoA-I (OR 35.89, 95% CI 6.08–211.7, p < 0.0001) and use of patch material (OR 9.26, 95% CI 1.57–54.66, p = 0.014) were associated with increased risk of RAAO. The odds of developing RAAO was higher in patients with a CoA-I less than 0.7 (OR 33.8, 95% CI 5.7–199.5, p < 0.001). Postoperative CoA-I may be used to predict RAAO in patients with biventricular circulation after repair of CoA. Patients with a CoA-I less than 0.7 or patch aortoplasty warrant close follow-up.



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Exercise Capacity and Self-Efficacy are Associated with Moderate-to-Vigorous Intensity Physical Activity in Children with Congenital Heart Disease

Abstract

This study sought to determine whether exercise capacity, self-efficacy, and gross motor skills are associated with moderate-to-vigorous physical activity (MVPA) levels in children, and if these associations differ by congenital heart disease (CHD) type. Medical history was abstracted from chart review. We assessed MVPA levels (via accelerometry), percent-predicted peak oxygen consumption ( \(V__{2} }} ;\) cardiopulmonary exercise test), gross motor skill percentiles (test of gross motor development version-2), and self-efficacy [children's self-perceptions of adequacy and predilection for physical activity scale (CSAPPA scale)]. CHD patients (n = 137, range 4–12 years) included children with a repaired atrial septal defect (n = 31, mean ± standard deviation MVPA = 454 ± 246 min/week), transposition of the great arteries after the arterial switch operation (n = 34, MVPA = 423 ± 196 min/week), tetralogy of Fallot after primary repair (n = 37, MVPA = 389 ± 211 min/week), or single ventricle after the Fontan procedure (n = 35, MVPA = 405 ± 256 min/week). MVPA did not differ significantly between CHD groups (p = 0.68). Higher MVPA was associated with a higher percent-predicted \(V__{2} }}\) (EST[95% CI] = 16.9[−0.2, 34] MVPA min/week per 10% increase in percent-predicted \(V__{2} }} ,\) p = 0.05) and higher self-efficacy (EST[95% CI] = 5.2[1.0, 9.3] MVPA min/week per 1-unit increase in CSAPPA score, p = 0.02), after adjustment for age, sex, and testing seasonality, with no association with CHD type. Higher MVPA was not associated with gross motor skill percentile (p = 0.92). There were no significant interactions between CHD type and percent-predicted \(V__{2} }} ,\) self-efficacy scores, and gross motor skill percentiles regarding their association with MVPA (p > 0.05 for all). Greater MVPA was associated with higher exercise capacity and self-efficacy, but not gross motor skills.



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Hypoplastic Left Heart Syndrome Sequencing Reveals a Novel NOTCH1 Mutation in a Family with Single Ventricle Defects

Abstract

Hypoplastic left heart syndrome (HLHS) has been associated with germline mutations in 12 candidate genes and a recurrent somatic mutation in HAND1 gene. Using targeted and whole exome sequencing (WES) of heart tissue samples from HLHS patients, we sought to estimate the prevalence of somatic and germline mutations associated with HLHS. We performed Sanger sequencing of the HAND1 gene on 14 ventricular (9 LV and 5 RV) samples obtained from HLHS patients, and WES of 4 LV, 2 aortic, and 4 matched PBMC samples, analyzing for sequence discrepancy. We also screened for mutations in the 12 candidate genes implicated in HLHS. We found no somatic mutations in our HLHS cohort. However, we detected a novel germline frameshift/stop-gain mutation in NOTCH1 in a HLHS patient with a family history of both HLHS and hypoplastic right heart syndrome (HRHS). Our study, involving one of the first familial cases of single ventricle defects linked to a specific mutation, strengthens the association of NOTCH1 mutations with HLHS and suggests that the two morphologically distinct single ventricle conditions, HLHS and HRHS, may share a common molecular and cellular etiology. Finally, somatic mutations in the LV are an unlikely contributor to HLHS.



http://ift.tt/2r9h49g

Transnasal endoscopic ultrasound-guided reduction of maxillary sinus wall fracture

Abstract

Surgical morbidity from open reduction and internal fixation (ORIF) of maxillary sinus wall fracture often surpasses the benefits of ORIF. Hence, the authors devised transnasal endoscopic-assisted reduction of maxillary sinus wall fracture (TERM) without internal fixation as a minimally invasive surgery for maxillary sinus wall fracture. The purpose of this study was to investigate the feasibility of TERM in cadavers and patients. Six cadavers were dissected to evaluate the feasibility of TERM. In addition, 20 patients with maxillary sinus wall fractures who underwent TERM in a tertiary hospital from August of 2013 to December of 2015 were enrolled in this study. Demographic factors, type of anesthesia, computed tomography (CT) scans, clinical characteristics of patients, and patient satisfaction with surgery were analyzed. Cadaveric study showed that endoscopic inferior meatus antrostomy is a feasible method of approaching the maxillary sinus wall in cadavers. In addition, counterforce could be applied to the maxillary sinus wall by pushing packed Vaseline-soaked gauze or using a zygomatic process approach via a Gillies incision. Clinical experience revealed that patients experienced good facial contour restoration postoperatively. The extent of fractured bony segments was reduced on postoperative CT without complications. Patient satisfaction with TERM was greater than that with ORIF (p = 0.031). TERM showed its feasibility in both cadaveric study and clinical study. TERM can be a good alternative to ORIF, especially in patients who are reluctant to undergo a facial incision.



http://ift.tt/2rh3DYN

Clinical evaluation of zirconia-based all-ceramic single crowns: an up to 12-year retrospective cohort study

Abstract

Objectives

This study aims to investigate the incidence of clinical complications with tooth-supported zirconia-based all-ceramic single crowns and identify pertinent risk parameters.

Materials and methods

A retrospective cohort study (May 2004 to April 2016) utilizing clinical records of patients receiving yttrium-oxide–partially stabilized zirconia (Y-TZP)-based all-ceramic crowns placed at Tohoku University Hospital was performed. The length of time of treatment success (complication event-free) and restoration survival (including minor complication events and remaining clinically functional) were estimated using Kaplan–Meier analysis. Multilevel survival analysis was used to identify risk factors.

Results

One hundred thirty-seven crowns were evaluated (mean follow-up time, 7.0 years). A total of 21 crowns experienced at least one complication with fracture of veneering ceramic being the most common (16 crowns). Estimated success and survival rates at 5 years (96.9 and 98.5%, respectively) decreased at 10 years to 62.1 and 67.2%, respectively. The risk of complications was significantly higher for molar crowns compared to anterior crowns (p < 0.01). A significant association of complications with metal antagonist restorations was shown by univariate analysis (p < 0.01).

Conclusions

Given the study limitations, Y-TZP single crowns placed on anterior teeth demonstrated encouraging clinical results over a period of up to 10 years. However, there is a substantial risk of complications with posterior teeth within 10 years of restoration placement.

Clinical relevance

Treatment with zirconia-based all-ceramic crowns for molar teeth with metal antagonist occlusion should be undertaken with caution.



http://ift.tt/2sdwOLJ

Craniofacial and dental characteristics of patients with vitamin-D-dependent rickets type 1A compared to controls and patients with X-linked hypophosphatemia

Abstract

ᅟObjectives

Vitamin-D-dependent rickets type 1A (VDDR1A) is a rare inherited disease caused by defective activation of vitamin D. The aim of the study was to describe the craniofacial characteristics and the dental phenotype of patients with genetically confirmed VDDR1A. The VDDR1A findings were compared to findings in patients with X-linked hypophosphatemia (XLH) and healthy controls.

Material and methods

Ten patients with VDDR1A were identified. The reference group for the comparison of cephalometric findings was 49 adults without chronic disease. The reference group for the comparison of dental findings was 30 adults with XLH. Clinical examination, clinical photos, and radiographs were obtained. Cephalometric analysis was performed. Photos and radiographs were visually evaluated.

Results

The depth of the posterior cranial fossa (d-p and d-s-iop) in VDDR1A adults was reduced compared to the reference group (p < 0.05). Five (83%) of six adults with VDDR1A and one (4%) of 25 adults with XLH had enamel hypoplasia on several incisors and/or canines (p < 0.001). Three (75%) of four adults with VDDR1A and none of 16 adults with XLH had several first molars with enamel hypoplasia (p = 0.004). Five of 7 (71%) adults with VDDR1A and 24 of 30 (80%) adults with XLH had endodontically affected teeth.

Conclusions

The dental aberration of VDDR1A is more in line with the dental aberration of nutritional rickets than with the dental aberrations in XLH, suggesting the combination of low availability of both calcium and phosphate to be critical in periods of enamel formation.

Clinical relevance

Knowledge on craniofacial and dental aberration in patients with rare diseases, e.g., inherited rickets, is of importance to the dental practitioner, especially during diagnostics and treatment in special care units.



http://ift.tt/2tboLwa

CFTR-France, a national relational patient-database for sharing genetic and phenotypic data associated with rare CFTR variantsa

ABSTRACT

Most of 2,000 variants identified in the CFTR (cystic fibrosis transmembrane regulator) gene are rare or private. Their interpretation is hampered by the lack of available data and resources, making patient care and genetic counseling challenging. We developed a patient-based database dedicated to the annotations of rare CFTR variants in the context of their cis- and trans-allelic combinations. Based on almost 30 years' experience of CFTR testing, CFTR-France (http://ift.tt/2sdz6u7) currently compiles 16,819 variant records from 4,615 individuals with cystic fibrosis (CF) or CFTR-RD (related disorders), fetuses with ultrasound bowel anomalies, newborns awaiting clinical diagnosis and asymptomatic compound heterozygotes. For each of the 736 different variants reported in the database, patient characteristics and genetic information (other variations in cis or in trans) have been thoroughly checked by a dedicated curator. Combining updated clinical, epidemiological, in silico or in vitro functional data helps to the interpretation of unclassified and the reassessment of misclassified variants. This comprehensive CFTR database is now an invaluable tool for diagnostic laboratories gathering information on rare variants, especially in the context of genetic counseling, prenatal and preimplantation genetic diagnosis. CFTR-France is thus highly complementary to the international database CFTR2 focused so far on the most common CF-causing alleles.

This article is protected by copyright. All rights reserved



from #AlexandrosSfakianakis via Alexandros G.Sfakianakis on Inoreader http://ift.tt/2tbnSDR
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Modified Frailty Index Score and Perioperative Risk in Laryngectomy : The 11 Variables Included in Modified Frailty Index Assessment : History of diabetes Functional status (not independent at baseline) History of pneumonia or chronic obstructive pulmonary disease History of congestive cardiac failure History of myocardial infarction History of percutaneous coronary intervention, stent placement, or angina History of hypertension (requiring medical treatment) History of peripheral vascular disease or ischemic rest pain History of impaired sensorium History of transient ischemic attack or cerebrovascular accident History of cerebrovascular accident with neurologic deficit

http://orlhealth.blogspot.com/2017/06/modified-frailty-index-score-and.html

Alexandros Sfakianakis
Anapafseos 5 . Agios Nikolaos
Crete.Greece.72100
2841026182
6948891480

Three iteratively reweighted least squares algorithms for $$L_1$$ L 1 -norm principal component analysis

Abstract

Principal component analysis (PCA) is often used to reduce the dimension of data by selecting a few orthonormal vectors that explain most of the variance structure of the data. \(L_1\) PCA uses the \(L_1\) norm to measure error, whereas the conventional PCA uses the \(L_2\) norm. For the \(L_1\) PCA problem minimizing the fitting error of the reconstructed data, we propose three algorithms based on iteratively reweighted least squares. We first develop an exact reweighted algorithm. Next, an approximate version is developed based on eigenpair approximation when the algorithm is near convergent. Finally, the approximate version is extended based on stochastic singular value decomposition. We provide convergence analyses, and compare their performance against benchmark algorithms in the literature. The computational experiment shows that the proposed algorithms consistently perform the best and the scalability is improved as we use eigenpair approximation and stochastic singular value decomposition.



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Barking Cough

https://youtu.be/IgZuVo81298?t=33

Alexandros Sfakianakis
Anapafseos 5 . Agios Nikolaos
Crete.Greece.72100
2841026182
6948891480

Bovine cough

Hyperspectral X-ray transmission imaging................................3D chemical imaging

http://orlhealth.blogspot.com/2017/06/hyperspectral-x-ray-transmission.html

Alexandros Sfakianakis
Anapafseos 5 . Agios Nikolaos
Crete.Greece.72100
2841026182
6948891480

Persistent lesion hyperintensity on brain diffusion-weighted MRI

http://orlhealth.blogspot.com/2017/06/persistent-lesion-hyperintensity-on.html

Alexandros Sfakianakis
Anapafseos 5 . Agios Nikolaos
Crete.Greece.72100
2841026182
6948891480

Nausea, vomiting, loss of appetite and oliguria : haemoglobin =12.7 g/dL, indirect bilirubin =2.0 mg/dL, haptoglobin ≤6 mg/dL, platelet count =121 000/μL and schistocytes on peripheral smear.

http://orlhealth.blogspot.com/2017/06/nausea-vomiting-loss-of-appetite-and.html

Alexandros Sfakianakis
Anapafseos 5 . Agios Nikolaos
Crete.Greece.72100
2841026182
6948891480

Controlled release of BSA-linked cisplatin through a PepGel self-assembling peptide nanofiber hydrogel scaffold

Abstract

Previously, it has been reported that a novel PepGel (h9e peptide) can be triggered into a solid physical hydrogel by the addition of selected ions and proteins for various biomedical applications. Moreover, PepGel displays shear-thinning and repeatedly reversible sol–gel transfer properties that enable it to be easily transferred via an injector. In this study, PepGel is proposed as a carrier for controlled releases of bovine serum albumin (BSA)-bound or -linked drugs. BSA-linked cisplatin (BSA–CP) is used as a model drug in this study and plays two roles: as a trigger of hydrogel and as a target drug for controlled release. Results of fluorescence instrument show that PepGel significantly quenches the fluorescence of Trp in the hydrophobic subdomain of BSA, indicating a strong interaction. Images of TEM and fluorescence confocal microscopy indicate that BSA–CP is dispersed in the PepGel fibers and at the same time enhances the fiber aggregation. Through UV instrument, it is found that PepGel can effectively inhibit the diffusion of BSA–CP even at concentrations below 0.3 wt% and that the rate of BSA–CP release could be controlled by adjusting the concentration of PepGel. Cell culture studies on the performance of the PepGel are carried out using HeLa cells, and the cell viability is observed to be consistent with the data of drug release. The results showed that PepGel nanofiber scaffolds could potentially be used as an effective carrier for controlled releases of BSA-bound or -linked drugs.



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An Ethical Dilemma: To Share or Not To Share Your Paper Published in Lipids Using an On-Line Outlet



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Bdm-Mediated Regulation of Flagellar Biogenesis in Escherichia coli and Salmonella enterica Serovar Typhimurium

Abstract

Synthesis of the flagellar apparatus in Escherichia coli is mediated via complex regulatory pathways. A previous study indicated that the protein encoded by the biofilm-dependent modulation (bdm) gene is linked closely with a regulatory pathway for flagellar assembly. However, the specific role of Bdm in flagellar biogenesis remains unknown. Herein, we showed that Bdm interacts with FlgM and inhibits its function as an anti-σ28 factor, which induces the transcription of flagellar late-class genes in E. coli. In addition, we observed that deletion of the yddX gene, a potential Salmonella enterica serovar Typhimurium homolog of bdm, also resulted in downregulation of flagellar late-class genes and in the formation of short flagella, leading to decreased virulence in mice. The expression levels of late-class flagellar genes in yddX-deleted S. Typhimurium cells were restored to those of the wild type when either E. coli bdm or S. Typhimurium yddX was expressed exogenously. These results suggest that Bdm-mediated regulation of flagellar assembly is a conserved regulatory pathway in those members of the Enterobacteriaceae family whose genomes show the existence of homologs of bdm.



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ATP Sulfurylase is Essential for the Utilization of Sulfamate as a Sulfur Source in the Yeast Komagataella pastoris (syn. Pichia pastoris )

Abstract

The methylotrophic yeast Komagataella pastoris (syn. Pichia pastoris) is one of the few known yeasts that can utilize sulfamate ( \({\text{NH}}_{2} {\text{SO}}_{3}^{ - }\) ) as a sulfur source. The biochemical pathway responsible for the catabolism of sulfamate has yet to be identified. The present study sought to investigate whether sulfamate catabolism proceeds through either of the inorganic sulfur intermediates sulfate ( \({\text{SO}}_{4}^{2 - }\) ) or sulfite ( \({\text{SO}}_{3}^{2 - }\) ) before its assimilation and subsequent incorporation into sulfur-containing amino acids and their derivatives. Two key genes in the K. pastoris inorganic sulfur assimilation pathway were deleted separately and the ability of each deletion mutant to utilize sulfamate and other selected sulfur sources was studied. Deletion of the MET3 gene (which encodes the enzyme ATP sulfurylase) did not affect growth on l-methionine, sulfite, methanesulfonate, or taurine but completely abolished growth on sulfate, methyl sulfate and sulfamate. Deletion of the MET5 gene (which encodes the β subunit of the enzyme sulfite reductase) abolished growth on all tested sulfur sources except l-methionine. These results suggest that the catabolism of sulfamate proceeds through a sulfate intermediate before its assimilation.



http://ift.tt/2rQC47u

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