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STUDY DESIGN: Retrospective study. PURPOSE: To analyze the results and effectiveness of percutaneous screws (PS) with midline microscopic transforaminal decompression (MTFD) technique in reducing adult stiff lytic high-grade spondylolisthesis (HGSL) and compare it with the conventional technique. OVERVIEW OF LITERATURE: Pedicle screw cannulation and segmental kyphosis negotiation are surgical challenges in HGSL. Open reduction is the preferred approach. PS have the advantage of optimized trajectory and minimized soft tissue exposure. The role of minimally invasive surgery in HGSL remains unknown. We propose a hybrid technique combining PS with MTFD for lytic HGSL. METHODS: This study included 25 patients with adult lytic HGSL (Meyerding grade III and IV) operated using a hybrid technique from 2012 to 2015. Data were compared with retrospective data on conventional open reduction (n=23) operated from 2000 to 2015. The minimum follow-up was 5 years. Clinical outcomes were assessed using the Visual Analog Scale (VAS) score and modified Oswestry Disability Index (m-ODI). The spinopelvic and perioperative parameters were recorded. The inter-body fusion and adjacent segment degeneration (ASD) were assessed on radiographs at the final follow-up. RESULTS: The average age in the MTFD and open groups was 45.84±12.70 years (nine males and 16 females) and 49.26±13.33 years (eight males and 15 females), respectively. Further, 22 and three patients in the MTFD group and 19 and four in the open group had grade III and IV listhesis, respectively. The MTFD group demonstrated less operative time, blood loss, and hospital stays than the open group. Significant improvements were observed in VAS and m-ODI in subsequent follow-ups in both groups. The MTFD group fared better at 3 months but outcomes were comparable at the final follow-up. Both techniques were equally effective in restoring spinopelvic parameters. The incidence of ASD is comparable. CONCLUSIONS: The technique was proven effective in reducing HGSL. The long-term clinical and radiological outcomes were favorable and comparable with the conventional approach.
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Biological degradation of plastic waste is an environmentally and economically friendlier alternative to current recycling practices and enables the cycling of plastic monomers back into virgin-quality plastics. However, due to slow reaction rates, there is a lack of an industrially viable biodegradation strategy for most plastics. Here, we highlight the applicability of a thermophilic biodegradation strategy over a mesophilic approach, to enhance enzyme accessibility and catalyze plastic biodegradation. Thus, at reactions closer to the melting temperature or glass transition temperature of plastics, thermophilic reactions can offer an alternative direction to conventional plastic biodegradation strategies.
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Plásticos , Reciclaje , Plásticos/metabolismo , Biodegradación AmbientalRESUMEN
CASE REPORT AND LITERATURE REVIEW: The aim of this study was to report a rare case of hydrocephalus due to ventriculoperitoneal shunt (VPS) malfunction following kyphosis correction that resulted in paraplegia in the postoperative period. The available English literature to explain the possible cause of paraplegia is reviewed. Twelve-year male child presented with a severe dorsal kyphoscoliosis deformity with spastic paraparesis since 4 months. The lower extremities had grade-2 power and spasticity. The sensation was reduced below D9. The deep tendon reflexes were exaggerated with ankle clonus. Bowel-bladder had urgency and frequency. The radiographs and CT showed D6-7 hemi-vertebra with complex kyphoscoliosis deformity. magnetic resonance imaging showed a stretching cord at D6-7 due to 92° angular kyphosis. The somatosensory evoked potential showed posterior column involvement. The VPS was placed for hydrocephalus at 4 months of age. The shunt remained functioned throughout childhood. He underwent posterior vertebral column resection and kyphosis correction surgery. Postoperative CNS function was normal. Neurology was status quo. After 20âhours, the boy appeared irritable, confused with a headache and repetitive vomiting (Glasgow coma scale: 7-8/15). Computed tomography brain showed dilated both ventricles with left shunt in situ. Immediate re-shunting was done from right side. The CNS status improved dramatically and regained consciousness. Neurology deteriorated to grade-0 with increased spasticity and further decreased sensation below D9. The spinal causes (hematoma, implant malposition, syrinx) were ruled out. Delayed neurological recovery was seen at 6th week after shunt surgery. The Rapid motor march was observed and became independent ambulatory at 12th week. At 6 months, he improved up-to grade4 power with grade 2 spasticity which maintained at 2 years. VPS blockage caused a sudden hydrocephalus which increased CSF pressure within the spinal cord and decreased cord perfusion. Spinal cord at apex of deformity was vulnerable to ischemia which caused paraplegia.^ieng
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Cifosis , Derivación Ventriculoperitoneal , Humanos , Cifosis/diagnóstico por imagen , Cifosis/etiología , Cifosis/cirugía , Paraplejía/etiología , Resultado del Tratamiento , Derivación Ventriculoperitoneal/efectos adversosRESUMEN
STUDY DESIGN: Case report. OBJECTIVE: To describe a modified posterior approach for decompression and excision of a multiloculated atlanto-axial cyst. SUMMARY OF BACKGROUND DATA: Atlanto-axial cyst with myelopathy is rare. A direct decompression through anterior approach or an indirect decompression through posterior approach has been proposed. We report a rare multiloculated large C1-C2 cyst extending down to C3 body with myelopathy that created a dilemma in choice of approach. A modified posterior approach was adopted for decompression. METHODS: A 72-year-old lady, known case of Rheumatoid arthritis, presented with cervical myelopathy which was rapidly progressive since 2 months being her to wheel chair bound. She had clumsiness of gait and bilateral grip weakness. Both upper and lower extremities had nonfunctional power (medical research council scale grade 2). Deep tendon reflexes were exaggerated. Sensation was reduced in trunk and both extremities. Magnetic resonance imaging and computed tomography scan showed a large multiloculated cyst compressing spinal cord. Here author used modified posterior approach from the right side to access the cyst. The C2 ganglion excision, vertebral artery isolation, and resection of the pars allowed an approach similar to transforaminal decompression in the lumbar spine. A large antero-lateral epidural part of the cyst was excised. The retro-dental cyst was decompressed by puncturing cyst. Biopsy confirmed a synovial cyst. RESULT: The patient showed rapid neurological recovery after surgery. Postoperative magnetic resonance imaging at 3 months showed complete resolution of cyst. At 2-year follow-up, there was a complete neurological recovery with residual spasticity. CONCLUSION: A customized posterior approach allowed near total excision of a rare multiloculated large C1-2 cyst extending to the C3 body. This allowed visualisation anterior to the spinal cord without undue retraction that saved an additional anterior decompression. LEVEL OF EVIDENCE: 5.
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Descompresión Quirúrgica/métodos , Enfermedades de la Médula Espinal/cirugía , Quiste Sinovial/cirugía , Anciano , Artritis Reumatoide/complicaciones , Vértebras Cervicales/cirugía , Femenino , Humanos , Imagen por Resonancia Magnética , Periodo Posoperatorio , Quiste Sinovial/diagnóstico por imagen , Tomografía Computarizada por Rayos XRESUMEN
STUDY DESIGN: Case report. OBJECTIVE: We report a rare case of congenital unilateral rotatory atlanto-occipital subluxation that presented with left C1 neuralgia. SUMMARY OF BACKGROUND DATA: Secondary occipital neuralgia is commonly attributed to pathologies of the atlanto-axial joint and C2/C3 nerve involvement. Our case depicts a model of slow creeping atlanto-occipital subluxation due to a rare left C1 superior articular facet dysplasia with C1 foraminal stenosis presenting as C1 neuralgia. We discuss the eitology and patho-anatomy of this rare undescribed presentation. METHODS: A 42-year-old gentleman presented with deteriorating and intractable left occipital headache of 6 months duration. The neck disability index (NDI) was 64%. Cervical MR/computed tomography scan showed a unilateral C1 facet dysmorphism with a left sided C1 foramen bony compression. There was no central canal stenosis. RESULTS: Posterior left C1 arch excision and decompression of C1 foramina with occipital-cervical fusion relieved C1 neuralgia. CONCLUSION: Our case depicts a model of slow creeping deformation due to left C1 superior articular facet dysplasia. An abnormal facet slope allowed the occipital condyle to migrate posteriorly and medially leading to crowding of the left C1 foramen. Although the etiology was congenital, the neck spasm was delayed till fourth decade. A secondary C1 foramen stenosis led to C1 occipital neuralgia that presented as an intractable headache. LEVEL OF EVIDENCE: 5.
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Articulación Atlantooccipital/cirugía , Luxaciones Articulares/congénito , Luxaciones Articulares/complicaciones , Neuralgia/etiología , Adulto , Descompresión Quirúrgica , Humanos , Luxaciones Articulares/cirugía , Masculino , Neuralgia/cirugía , Fusión Vertebral , Resultado del TratamientoRESUMEN
Microbacterium sp. strain TNHR37B was isolated from a geothermal bore well sample (50°C) collected from a region of coal seam gas extraction activities. The 3.5-Mb genome with a G+C content of 69.9% contained unique genes, and a low similarity value for average nucleotide identity using BLAST was observed with the available 73 Microbacterium sp. genomes.
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Micrococcus luteus strain NDB3Y10, which utilizes 1,2-dichloroethane as a carbon source, was isolated from a bore well that produces coal seam gas. The draft genome size of the strain was 2.49 Mb with a G+C content of 72.97%. Genes involved in the metabolism of halogenated substrates, including halogenated hydrocarbons, were identified.
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Cellulosilyticum sp. strain I15G10I2 was isolated from a coal seam gas water treatment pond at the Spring Gully water treatment facility, Roma, Queensland, Australia. Analysis of the genome of 4,489,861 bp and G+C content of 35.23% revealed that strain I15G10I2 shared limited similarity to members of the genus Cellulosilyticum, family Lachnospiraceae.
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Brucella abortus is generally known to cause brucellosis in cattle and buffalo. Here, we report the draft genome sequence of Brucella abortus SKN 13, isolated from aborted cattle placenta in the area of Gujarat, India, providing precious resources for comparative genomic analyses of Brucella field strains.
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The genome sequence of Caloramator mitchellensis strain VF08, a rod-shaped, heterotrophic, strictly anaerobic bacterium isolated from the free-flowing waters of a Great Artesian Basin (GAB) bore well located in Mitchell, an outback Queensland town in Australia, is reported here. The analysis of the 2.42-Mb genome sequence indicates that the attributes of the genome are consistent with its physiological and phenotypic traits.
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A thermophilic, heterotrophic and facultatively anaerobic bacterium designated strain D7XPN1 was isolated from Baku BakuKing™, a commercial food-waste degrading bioreactor (composter). The strain grew optimally at 45 °C (growth range between 24 and 50 °C) and pH 7 (growth pH range between pH 5 and 9) in Luria Broth supplemented with 0.3 % glucose. Strain D7XPN1 tolerated up to 7 % NaCl and showed amylolytic and xylanolytic activities. 16S rRNA gene analysis placed strain D7XPN1 in the cluster represented by Bacillus subtilis and the genome analysis of the 4.1 Mb genome sequence determined using RAST (Rapid Annotation using Subsystem Technology) indicated a total of 5116 genomic features were present of which 2320 features could be grouped into several subsystem categories. Of these, 615 features were related to carbohydrate metabolism which included a range of enzymes with potential in the biodegradation of food wastes, a property consistent with the ecological habitat of the isolate. ANIb (Average Nucleotide Identity based on BLAST) analysis with 49 Bacillus subtilis genomes indicated that it was distantly related to the three currently taxonomically validated B. subtilis subspecies namely B. subtilis subsp. subtilis (95.6 %), B. subtilis subsp. spizizenii (93 %) and B. subtilis subsp. inaquosorum (92 %) and based on our current knowledge warranted that it be included as a separate cluster together with strain JS which it was closely related (98.69 %). The close relationship of strains D7XPN1 and JS is also supported from our results from electronic DNA-DNA Hybridization (e-DDH) studies. Furthermore, our additional in-depth phylogenomic analyses using three different datasets unequivocally supported the creation of a fourth B. subtilis subspecies to include strains D7XPN1 and JS for which we propose strain D7XPN1T (=KCTC 33554T, JCM 30051T) as the type strain, and designate it as B. subtilis subsp. stecoris.
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Lactose is produced in large amounts as a by-product from the dairy industry. This inexpensive disaccharide can be converted to more useful value-added products such as galacto-oligosaccharides (GOSs) by transgalactosylation reactions with retaining ß-galactosidases (BGALs) being normally used for this purpose. Hydrolysis is always competing with the transglycosylation reaction, and hence, the yields of GOSs can be too low for industrial use. We have reported that a ß-glucosidase from Halothermothrix orenii (HoBGLA) shows promising characteristics for lactose conversion and GOS synthesis. Here, we engineered HoBGLA to investigate the possibility to further improve lactose conversion and GOS production. Five variants that targeted the glycone (-1) and aglycone (+1) subsites (N222F, N294T, F417S, F417Y, and Y296F) were designed and expressed. All variants show significantly impaired catalytic activity with cellobiose and lactose as substrates. Particularly, F417S is hydrolytically crippled with cellobiose as substrate with a 1000-fold decrease in apparent k cat, but to a lesser extent affected when catalyzing hydrolysis of lactose (47-fold lower k cat). This large selective effect on cellobiose hydrolysis is manifested as a change in substrate selectivity from cellobiose to lactose. The least affected variant is F417Y, which retains the capacity to hydrolyze both cellobiose and lactose with the same relative substrate selectivity as the wild type, but with ~10-fold lower turnover numbers. Thin-layer chromatography results show that this effect is accompanied by synthesis of a particular GOS product in higher yields by Y296F and F417S compared with the other variants, whereas the variant F417Y produces a higher yield of total GOSs.
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Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Galactosa/metabolismo , Halothiobacillus/enzimología , Oligosacáridos/biosíntesis , Ingeniería de Proteínas , beta-Glucosidasa/genética , beta-Glucosidasa/metabolismo , Proteínas Bacterianas/química , Halothiobacillus/química , Halothiobacillus/genética , Cinética , Lactosa/metabolismo , Especificidad por Sustrato , beta-Glucosidasa/químicaRESUMEN
A gene from the heterotrophic, halothermophilic marine bacterium Halothermothrix orenii has been cloned and overexpressed in Escherichia coli. This gene encodes the only glycoside hydrolase of family 43 (GH43) produced by H. orenii. The crystal structure of the H. orenii glycosidase was determined by molecular replacement and refined at 1.10â Å resolution. As for other GH43 members, the enzyme folds as a five-bladed ß-propeller. The structure features a metal-binding site on the propeller axis, near the active site. Based on thermal denaturation data, the H. orenii glycosidase depends on divalent cations in combination with high salt for optimal thermal stability against unfolding. A maximum melting temperature of 76°C was observed in the presence of 4â M NaCl and Mn(2+) at pH 6.5. The gene encoding the H. orenii GH43 enzyme has previously been annotated as a putative α-L-arabinofuranosidase. Activity was detected with p-nitrophenyl-α-L-arabinofuranoside as a substrate, and therefore the name HoAraf43 was suggested for the enzyme. In agreement with the conditions for optimal thermal stability against unfolding, the highest arabinofuranosidase activity was obtained in the presence of 4â M NaCl and Mn(2+) at pH 6.5, giving a specific activity of 20-36â µmolâ min(-1)â mg(-1). The active site is structurally distinct from those of other GH43 members, including arabinanases, arabinofuranosidases and xylanases. This probably reflects the special requirements for degrading the unique biomass available in highly saline aqueous ecosystems, such as halophilic algae and halophytes. The amino-acid distribution of HoAraf43 has similarities to those of mesophiles, thermophiles and halophiles, but also has unique features, for example more hydrophobic amino acids on the surface and fewer buried charged residues.
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Proteínas Bacterianas/química , Firmicutes/enzimología , Glicósido Hidrolasas/química , Secuencia de Aminoácidos , Dominio Catalítico , Cristalografía por Rayos X , Cinética , Modelos Moleculares , Estructura Secundaria de Proteína , Especificidad por SustratoRESUMEN
Anoxybacillus strain BCO1, isolated from a thermophilic (50°C) microbial mat colonizing an outflow of a Great Artesian bore well of Australia, possessed a genome of ~2.8 Mb, with a G+C content of 41.7 mol%, and encoded 3,205 genes.
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The analysis of the ~5.8-Mb draft genome sequence of a moderately thermophilic, heterotrophic, facultative anaerobic bacterium, Paenibacillus strain P1XP2, identified genes for enzymes with the potential for degrading complex food wastes, a property consistent with the ecological habitat of the isolate.
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Lactose is a major disaccharide by-product from the dairy industries, and production of whey alone amounts to about 200 million tons globally each year. Thus, it is of particular interest to identify improved enzymatic processes for lactose utilization. Microbial ß-glucosidases (BGL) with significant ß-galactosidase (BGAL) activity can be used to convert lactose to glucose (Glc) and galactose (Gal), and most retaining BGLs also synthesize more complex sugars from the monosaccharides by transglycosylation, such as galacto-oligosaccharides (GOS), which are prebiotic compounds that stimulate growth of beneficial gut bacteria. In this work, a BGL from the thermophilic and halophilic bacterium Halothermothrix orenii, HoBGLA, was characterized biochemically and structurally. It is an unspecific ß-glucosidase with mixed activities for different substrates and prominent activity with various galactosidases such as lactose. We show that HoBGLA is an attractive candidate for industrial lactose conversion based on its high activity and stability within a broad pH range (4.5-7.5), with maximal ß-galactosidase activity at pH 6.0. The temperature optimum is in the range of 65-70 °C, and HoBGLA also shows excellent thermostability at this temperature range. The main GOS products from HoBGLA transgalactosylation are ß-D-Galp-(1â6)-D-Lac (6GALA) and ß-D-Galp-(1â3)-D-Lac (3GALA), indicating that D-lactose is a better galactosyl acceptor than either of the monosaccharides. To evaluate ligand binding and guide GOS modeling, crystal structures of HoBGLA were determined in complex with thiocellobiose, 2-deoxy-2-fluoro-D-glucose and glucose. The two major GOS products, 3GALA and 6GALA, were modeled in the substrate-binding cleft of wild-type HoBGLA and shown to be favorably accommodated.
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Clostridium/enzimología , Galactosa/metabolismo , Lactosa/metabolismo , Oligosacáridos/biosíntesis , beta-Glucosidasa/genética , beta-Glucosidasa/metabolismo , Clostridium/genética , Cristalografía por Rayos X , Estabilidad de Enzimas , Glucosa/metabolismo , Concentración de Iones de Hidrógeno , Modelos Moleculares , Conformación Proteica , Especificidad por Sustrato , Temperatura , beta-Glucosidasa/químicaRESUMEN
The analysis of the 4.1-Mb draft genome sequence of a moderately thermophilic, heterotrophic, and facultatively anaerobic bacterium, Bacillus subtilis strain D7XPN1, identified genes for a range of enzymes with potential in the biodegradation of food waste, a property consistent with the ecological habitat of the isolate.
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The genome sequence of Fervidicella metallireducens strain AeB(T), a curved, heterotrophic, thermoanaerobic, and iron-reducing bacterium isolated from a gray microbial mat colonizing the free-flowing waters of a Great Artesian Basin (GAB) bore well located in outback Queensland, Australia, is reported here. The analysis of the 2.9-Mb sequence indicates that the attributes of the genome are consistent with its physiological and phenotypic traits.
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An anaerobic, moderately thermophilic, terminal-spore-forming bacterium, designated strain USBA A(T), was isolated from a terrestrial hot spring located at an altitude of 2683 m in the Andean region of Colombia (04° 50' 14.0â³ N 75° 32' 53.4â³ W). Cells of strain USBA A(T) were Gram-stain-positive, straight to slightly curved rods (0.9×2.5 µm), that were arranged singly or in pairs, and were motile by means of flagella. Growth occurred at 37-55 °C and pH 6.0-8.0, with a doubling time of 2 h under the optimal conditions (50 °C and pH 7.0). Glucose fermentation in strain USBA A(T) required yeast extract or peptone (each at 0.2â%, w/v). The novel strain fermented sugars, amino acids, Casamino acids, propanol, propionate, starch and dextrin, but no growth was observed on galactose, lactose, xylose, histidine, serine, threonine, benzoate, butyrate, lactate, pyruvate, succinate, methanol, ethanol, glycerol, casein, gelatin or xylan. The end products of glucose fermentation were formate, acetate, ethanol and lactate. Strain USBA A(T) did not grow autotrophically (with CO2 as carbon source and H2 as electron donor) and did not reduce thiosulfate, sulfate, elemental sulfur, sulfite, vanadium (V) or Fe (III) citrate. Growth of strain USBA A(T) was inhibited by ampicillin, chloramphenicol, kanamycin, penicillin and streptomycin (each at 10 µg ml(-1)). The predominant fatty acids were iso-C15â:â0, C16â:â0 and iso-C17â:â0 and the genomic DNA G+C content was 32.6 mol%. 16S rRNA gene sequence analysis indicated that strain USBA A(T) belonged in the phylum Firmicutes and that its closest relative was Caloramator viterbiensis JW/MS-VS5(T) (95.0â% sequence similarity). A DNA-DNA relatedness value of only 30â% was recorded in hybridization experiments between strain USBA A(T) and Caloramator viterbiensis DSM 13723(T). Based on the phenotypic, chemotaxonomic and phylogenetic evidence and the results of the DNA-DNA hybridization experiments, strain USBA A(T) represents a novel species of the genus Caloramator, for which the name Caloramator quimbayensis sp. nov. is proposed. The type strain is USBA A(T) (â=âCMPUJ U833(T) â=âDSM 22093(T)).