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At least 19 recordsLinked to original sources

PubMed1979

Mechanism for circularization of linear DNAs: circular parvovirus MVM DNA is formed by a "noose" sliding in a "lasso"-like DNA structure.

During an electron-microscopic survey with the aim of identifying the parvovirus MVM transcription template, we observed previously unidentified structures of MVM DNA in lysates of virus-infected cells. These included double-stranded "lasso"-like structures and relaxed circles. Both structures were of unit length MVM DNA, indicating that they were not intermediates formed during replication; they each represented about 5% of the total nuclear MVM DNA. The proportion of these structures was unchanged after digestion with sodium dodecyl sulfate/Pronase and RNase and after mild denaturation treatment. Cleavage of the "lasso" structures with EcoRI restriction endonuclease indicated that the "noose" part of the "lasso" structure is located on the 5' side of the genomic single-stranded MVM DNA. A model is presented for the molecular nature of the circularization process of MVM DNA in which the "lasso" structures are identified as intermediates during circle formation. This model proposes a mechanism for circularization of linear DNAs.

DNA Replication↗

PubMed2006

Linear ablation of left atrium for the treatment of atrial fibrillation guided by double Lasso catheters and three dimensional electroanatomical mapping.

BACKGROUND: Linear ablation of left atrium (LA) guided by three dimensional (3-D) electroanatomical mapping (Carto) has been used in many centres worldwide for the treatment of atrial fibrillation (AF) instead of pure anatomical approaches. There were little data about linear ablation of LA guided by Carto and double Lasso catheters in China. We report the results of linear ablation of LA guided by both Carto and double Lasso catheters. METHODS: After the anatomical model of LA and all pulmonary veins (PVs) had been established, circumferential ablations of the left pulmonary vein antrum and the right pulmonary vein antrum were performed with 2 circumferential mapping catheters (Lasso) placed within the ipsilateral superior and inferior PVs. The endpoint of ablation was abolishment or dissociation of the pulmonary vein potentials (PVPs). Oral amiodarone or propafenone was taken for at least 3 months by patients with persistent AF, permanent AF or those whose PVPs had not been isolated completely. The recurrence of atrial tachyarrhythmias was observed 3 months after the procedure. RESULTS: There were 106 patients (mean age, 51.4 +/- 9.9 years). Seventy-eight patients had paroxysmal AF, 12 persistent AF and 16 permanent AF. Onset of atrial fibrillation occurred in 52 patients during ablation procedure. Thirty-two patients restored to sinus rhythm eventually after the procedure. Abolishment or dissociation of PVPs was accomplished during the procedure in 94 patients (88.7%). The duration of procedure and exposure to X-ray were (213 +/- 45) minutes and (32.5 +/- 12.8) minutes, respectively. Among the 87 patients followed up for over 3 months, 62 were free of atrial tachyarrhythmias (including 8 patients who were still taking oral amiodarone). The success rate was 71.3% in the first procedure. Two patients had pericardial effusion treated by pericardial puncture and effusion drainage. No pulmonary vein stenosis, atrioesophageal fistula, stroke or procedural death occurred. CONCLUSIONS: Combination of double Lasso catheters with 3-D electroanatomical mapping to guide the linear ablation of left atrium procedure can confirm the isolation of PVPs.

Adult↗

PubMed2024

Neobacillus driksii sp. nov. isolated from a Mars 2020 spacecraft assembly facility and genomic potential for lasso peptide production in Neobacillus.

UNLABELLED: During microbial surveillance of the Mars 2020 spacecraft assembly facility, two novel bacterial strains, potentially capable of producing lasso peptides, were identified. Characterization using a polyphasic taxonomic approach, whole-genome sequencing and phylogenomic analyses revealed a close genetic relationship among two strains from Mars 2020 cleanroom floors (179-C4-2-HS, 179-J1A1-HS), one strain from the Agave plant (AT2.8), and another strain from wheat-associated soil (V4I25). All four strains exhibited high 16S rRNA gene sequence similarity (>99.2%) and low average nucleotide identity (ANI) with Neobacillus niacini NBRC 15566T, delineating new phylogenetic branches within the genus. Detailed molecular analyses, including gyrB (90.2%), ANI (86.4%), average amino acid identity (87.8%) phylogenies, digital DNA-DNA hybridization (32.6%), and percentage of conserved proteins (77.7%) indicated significant divergence from N. niacini NBRC 15566T. Consequently, these strains have been designated Neobacillus driksii sp. nov., with the type strain 179-C4-2-HST (DSM 115941T = NRRL B-65665T). N. driksii grew at 4°C to 45°C, pH range of 6.0 to 9.5, and 0.5% to 5% NaCl. The major cellular fatty acids are iso-C15:0 and anteiso-C15:0. The dominant polar lipids include diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, and an unidentified aminolipid. Metagenomic analysis within NASA cleanrooms revealed that N. driksii is scarce (17 out of 236 samples). Genes encoding the biosynthesis pathway for lasso peptides were identified in all N. driksii strains and are not commonly found in other Neobacillus species, except in 7 out of 26 recognized species. This study highlights the unique metabolic capabilities of N. driksii, underscoring their potential in antimicrobial research and biotechnology. IMPORTANCE: The microbial surveillance of the Mars 2020 assembly cleanroom led to the isolation of novel N. driksii with potential applications in cleanroom environments, such as hospitals, pharmaceuticals, semiconductors, and aeronautical industries. N. driksii genomes were found to possess genes responsible for producing lasso peptides, which are crucial for antimicrobial defense, communication, and enzyme inhibition. Isolation of N. driksii from cleanrooms, Agave plants, and dryland wheat soils, suggested niche-specific ecology and resilience under various environmentally challenging conditions. The discovery of potent antimicrobial agents from novel N. driksii underscores the importance of genome mining and the isolation of rare microorganisms. Bioactive gene clusters potentially producing nicotianamine-like siderophores were found in N. driksii genomes. These siderophores can be used for bioremediation to remove heavy metals from contaminated environments, promote plant growth by aiding iron uptake in agriculture, and treat iron overload conditions in medical applications.

Phylogeny↗

PubMed2006

The lasso technique for laparoscopic distal pancreatectomy.

BACKGROUND: Laparoscopic distal pancreatectomy with or without splenectomy is becoming an acceptable alternative to open resection for selected pancreatic lesions. One of the difficulties with this approach is manipulating the pancreas with laparoscopic instruments to avoid unnecessary injury to the pancreas, and yet obtain adequate margins. The described technique accomplishes these goals. METHODS: Data from all patients who underwent laparoscopic distal pancreatectomy (always with splenectomy) were reviewed for age, gender, laparoscopic completion of the resection, postoperative complications, length of hospital stay, and pathology. The essential component of the technique is use of a Penrose drain around the neck or proximal body of the pancreas as a "lasso" for atraumatic manipulation. This technique is described in detail. RESULTS: A total of 11 patients have undergone laparoscopic distal pancreatectomy with splenectomy using the lasso technique. Two patients (18%) underwent conversion to an open laparotomy: the because of bleeding from the pancreatic parenchyma and the other due to local invasion of a pancreatic adenocarcinoma. The average operating time was 162 +/- 39 min, and the median length of hospital stay was 3 days. There were two (18%) pancreatic leaks, both of which were treated conservatively with resolution. Pathologic examination, found six cystic neoplasms, two neuroendocrine tumors, two masses of chronic pancreatitis, and one adenocarcinoma. CONCLUSIONS: The lasso technique simplifies intraoperative manipulation of the pancreas during laparoscopic distal pancreatectomy. It allows for safe manipulation of the pancreas and may expand the indications for the laparoscopic approach to pancreatic resection.

Aged↗

PubMed1996

MS-271, a novel inhibitor of calmodulin-activated myosin light chain kinase from Streptomyces sp.--II. Solution structure of MS-271: characteristic features of the "lasso' structure.

MS-271 is a potent inhibitor of smooth muscle myosin light chain kinase (MLCK), obtained from Streptomyces sp. In the previous paper, we reported on the isolation, structural determination and biological properties of MS-271.(1) In this paper, we report on the three-dimensional structure of MS-271 determined by 1H NMR in deuterated dimethyl sulphoxide. MS-271 consists of 21 amino acid residues with a novel internal linkage between the beta-carboxyl group of Asp9 and the alpha-amino group of Cysl, and two disulfide bonds, Cys1-Cys13 and Cys7-Cys19. The internal linkage between the side chain of Asp9 and the alpha-amino group of the N-terminal residue is the same as that of the endothelin B receptor selective antagonist, RES-701-1, that we previously reported. The structural calculations involved the combined use of distance geometry and simulated annealing calculations. The results indicated that MS-271 undergoes extraordinary folding, i.e. the "tail' (Phe10-dTrp21) passes through the "ring' region (Cys1-Asp9) ("lasso' structure). This folding of MS-271 turned out to be the same as the "lasso' structure of RES-701-1. The features of this "lasso' structure are discussed on the basis of comparison between the structures of MS-271 and RES-701-1.

Amino Acid Sequence↗

PubMed1998

Lasso procedure to revise overcorrection with radial keratotomy.

PURPOSE: To report three patients who underwent the lasso procedure to revise overcorrection with radial keratotomy. METHODS: Case report and review of the literature. RESULTS: Four eyes of three patients who had undergone radial keratotomy with resultant hyperopic overcorrection underwent a lasso procedure. Before the procedure, average cycloplegic refraction spherical equivalent was +3.656 +/- 1.352 diopters, and average manifest refraction spherical equivalent was +2.250 +/- 0.621 diopters. A 10.0 monofilament nylon suture was placed in a circumferencial manner through the corneal stroma and overlapping the old radial keratotomy incisions. At 1 month postoperatively, best-corrected visual acuity was 20/20 in all four eyes, with average cycloplegic refraction spherical equivalent +0.438 +/- 1.423 diopters and average manifest refraction spherical equivalent -0.156 +/- 1.147 diopters. Mean delta cycloplegic refraction spherical equivalent was 3.219 +/- 1.724. CONCLUSIONS: The lasso procedure provides an immediate solution for symptomatic overcorrected hyperopic eyes after radial keratotomy. Predictability and long-term stability necessitate further follow-up.

Adult↗

PubMed1999

Retrieval of distally migrated, impacted biliary endoprostheses using a novel guidewire/basket "lasso" technique.

BACKGROUND: Migration of biliary endoprostheses is a recognized complication of bile duct stenting. Removing a stent that has migrated is usually straightforward, but this can be challenging when the stent is firmly impacted in the opposite wall of the duodenum or within a diverticulum. We describe a new technique for removing such impacted stents using a guidewire/basket lasso. METHODS: To perform the lasso technique, a retrieval basket and a guidewire are passed side-by-side through the accessory channel of the duodenoscope. The basket catheter is advanced underneath the stent and the guidewire manipulated over the stent; the basket is opened and the guidewire advanced through it. Closure of the basket creates a loop around the stent that can then be removed using gentle traction. RESULTS: The lasso technique was successfully used in three cases where other maneuvers failed. CONCLUSIONS: Biliary endoscopists should find this technique useful for retrieval of distally migrated biliary stents that are impacted against mucosa or the wall of a diverticulum so as to prevent standard basket extraction.

Aged↗

PubMed1988

Ureteral stone extraction with the Steffens lasso loop. A neglected procedure.

The main advantages of the Steffens lasso loop are its olive-tipped, 45 degrees-angled Tiemann guide, which allows easier and less traumatic passage above the ureteral stone, the tri-part lasso, which affords a better grasp of the stone, and the outlet for urine drainage. Between 1976 and 1986 we used this loop in 560 of 919 patients with distal ureteral stones. Immediate stone extraction was possible in 85.7% of the patients treated in 1986. Perforation of the ureter occurred in 2.3%, and 3% required ureterolithotomy. Our experience with this lasso loop has shown this instrument to be a valuable addition to other endourological methods.

Humans↗

PubMed1992

The effect of Lasso herbicide on human immune function as measured by in vitro assays.

Using in vitro assays, this study was undertaken to determine whether the components of Lasso herbicide formulation had an effect on the human immune system. Mononuclear cells from human peripheral blood were exposed to analytical alachlor, alachlor conjugated to human serum albumin or Lasso formulation over a concentration range from .01 microM-1.0 microM. The effects of the test materials on the following immunological functions were determined: lymphocyte proliferation induced by mitogen or antigen; antibody synthesis of IgG and IgM isotypes in pokeweed stimulated mononuclear cell cultures; cytotoxic T cell proliferation; lysis of target cells by natural killer cells and lymphokine activated killer cells. The data demonstrated that the test compounds had no significant, dose related effect on the function of immunocompetent cells. Hence, the data suggest that the components of the Lasso formulation have no effect on the human immune system.

Acetamides↗

PubMed2005

[Left atrium linear lesion encircling pulmonary veins guided by EnSite-NavX and double-Lasso technique for paroxysmal atrial fibrillation].

OBJECTIVE: To evaluate the efficacy of left atrium linear lesion encircling pulmonary veins (PV) guided by EnSite-NavX and double-Lasso technique for paroxysmal atrial fibrillation (PAF). METHODS: Twenty-two patients (male 19, mean age of 48.5 years +/- 11.4 years) with symptomatic PAF were enrolled. After a geometry of the left atrium was reconstructed by EnSite-NavX system, PV ostia were marked on the map based on venography. Two Lasso catheters were placed within the ipsilateral superior and inferior PVs. Irrigated radiofrequency energy was applied at 0.5-1.0 cm of distance from the PV ostia. Continuous linear lesion was done to obtain the disappearance of pulmonary vein potentials. Patients were on propafenone and perindopril for three months after the procedure. RESULTS: The endpoint for ablation was reached in 21 Patients and 1 patient was not successful because of cardiac tamponade. The mean procedure time was 6.6 h +/- 1.3 h and the mean X-ray exposure time was 56.1 min +/- 18.0 min. After a mean 5.3 months +/- 2.7 months of follow-up, 10 patients were free of symptoms. Two patients had no PAF recurrence after the second procedure. Three patients had clinical recurrence of PAF in the first month. The total success rate in this study was 81% (17/21). Mortality was 0% and the overall complication rate was about 9% (2/22). CONCLUSION: Left atrium circumferential linear ablation surrounding PV ostia guided by EnSite-NavX and double-Lasso technique is effective in PAF, but some patients will need more than one procedure in order to achieve a success.

Adult↗

PubMedDate not supplied

[Homicide by strangulation with a lasso sling].

A 50-year-old physically handicapped man was found dead on his wheelchair in a short passage on the ground floor of a high-rise housing development. The lattice doors at the both ends of the passage were closed and the wheelchair with the body was found at the door to an adjoining indoor parking place for bicycles. A noose of a vinyl plastic cord was found wound around the neck; the other end of the cord was tied through the lattice door to a handrail on the wall of the parking place. The wheelchair was stopped sideways; its chair back was in contact with a doorpost. The body which was slipped from the seat of the wheelchair was incompletely suspended by the noose. The cause of death primarily was diagnosed as hanging. The police suspected murder and arrested a 21-year-old male assailant. According to his confession, the assailant pushed the wheelchair through the lattice door in the passage, stopped it at the door and braked it. Immediately thereafter he returned to the parking place and locked the lattice door behind him. After having made a kind of lasso using a cord taken off from a bicycle which has been sitting there, he reached out his hands through the lattice door and lassoed the man on the wheelchair from behind. Finally, he tied another end of the lasso to the handrail. It was considered that the body of the victim was slipped down in the stage of convulsion and incompletely suspended by the noose.

Asphyxia↗

PubMed1997

The lasso method for variable selection in the Cox model.

I propose a new method for variable selection and shrinkage in Cox's proportional hazards model. My proposal minimizes the log partial likelihood subject to the sum of the absolute values of the parameters being bounded by a constant. Because of the nature of this constraint, it shrinks coefficients and produces some coefficients that are exactly zero. As a result it reduces the estimation variance while providing an interpretable final model. The method is a variation of the 'lasso' proposal of Tibshirani, designed for the linear regression context. Simulations indicate that the lasso can be more accurate than stepwise selection in this setting.

Humans↗

PubMed2004

[The "necktie lasso": a new technique for the simultaneous treatment of Wartenberg's sign and claw deformities in the hand due to ulnar nerve palsy].

The "necktie lasso" is a new technique that allows the simultaneous active treatment, of both Wartenberg's sign and claw deformity of the fifth and the fourth digits in the hand with ulnar nerve palsy. The flexor sublimis of the fourth digit is taken by a palmar approach. It is then divided into two strips up to the proximal part of the palm; The radial strip is used as a classical "direct lasso" to treat the claw deformity of the fourth digit; The ulnar strip is wound around the base of the fifth digit by a palmar and dorsal approaches at the level of the proximal phalanx, like a necktie, being medial to its radial pedicle, dorsal and superficial to its extensor apparatus, then lateral to its ulnar pedicle; It is then recovered in the palm and sutured to itself. From September 1998 to April 2003, this technique has been used in eight patients aged between 21 and 35 years old and suffering from post traumatic low ulnar nerve palsy. It was always very effective in dealing with Wartenberg's sign: the active adduction of the fifth digit appearing at the start of flexion. The claw deformity of the fourth and fifth digits was equally actively corrected. No complications are reported in this series. With a mean follow-up of 3 years there was no recurrence of any of the deformities.

Adult↗

PubMed1985

Zancolli's "lasso" operation in intrinsic palsy of leprous origin. A study of twenty-six cases.

Twenty-six cases of Zancolli's "lasso" procedure are presented. They were part of a series of 122 operations performed for leprosy in Central Africa. Nineteen cases with a follow-up of more than 6 months were reviewed. Fifteen of these patients had good or very good results. When claw hand deformities are supple, one flexor superficialis tendon may be used for two fingers; when the fingers are partially stiff, one tendon for each finger should be used. The "lasso" procedure is simple and the results are satisfactory, particularly in this series of patients who did not follow any rehabilitation program.

Adult↗

PubMed2025

Sparse polygenic risk score inference with the spike-and-slab LASSO.

MOTIVATION: Large-scale biobanks, with rich phenotypic and genomic data across hundreds of thousands of samples, provide ample opportunities to elucidate the genetics of complex traits and diseases. Consequently, there is growing demand for robust and scalable methods for disease risk prediction from genotype data. Inference in this setting is challenging due to the high-dimensionality of genomic data, especially when coupled with smaller sample sizes. Popular Polygenic Risk Score (PRS) inference methods address this challenge by adopting sparse Bayesian priors or penalized regression techniques, such as the Least Absolute Shrinkage and Selection Operator (LASSO). However, the former class of methods are not as scalable and do not produce exact sparsity, while the latter tends to over-shrink large coefficients. RESULTS: In this study, we present SSLPRS, a novel PRS method based on the Spike-and-Slab LASSO (SSL) prior, which offers a theoretical bridge between the two frameworks. We extend previous work to derive a coordinate-ascent inference algorithm that operates on GWAS summary statistics, which is orders-of-magnitude more efficient than corresponding individual-level-based implementations. To illustrate the statistical properties of the proposed model, we conducted experiments involving nine simulation configurations and nine quantitative phenotypes from the UK Biobank. Our results demonstrate that SSLPRS is competitive with state-of-the-art methods in terms of prediction accuracy and exhibits superior variable selection performance, especially in sparse genetic architectures. In simulations, this translates to upwards of 50% improvement in positive predictive value. In analysis of real phenotypes, we show that selected variants are highly enriched for meaningful genomic annotations and have better replication rates in larger meta-analyses. AVAILABILITY AND IMPLEMENTATION: SSLPRS is available in the open-source package https://github.com/li-lab-mcgill/penprs.

Multifactorial Inheritance↗

PubMed2005

The "Lasso-o" tape: stretchability and observer variability in head circumference measurement.

Head circumference is an important clinical measurement in children. The stretchability of the Lasso-o tape and the intra- and inter-observer reproducibility of measurements using it were investigated. Old Lasso-o tapes stretch significantly. The intra-class coefficients were 0.999 for intra-observer and 0.979 for inter-observer measurements. Nonetheless in 9% of measurements inter-observer variability was over 1 cm.

Adolescent↗

PubMed2005

Classification and selection of biomarkers in genomic data using LASSO.

High-throughput gene expression technologies such as microarrays have been utilized in a variety of scientific applications. Most of the work has been done on assessing univariate associations between gene expression profiles with clinical outcome (variable selection) or on developing classification procedures with gene expression data (supervised learning). We consider a hybrid variable selection/classification approach that is based on linear combinations of the gene expression profiles that maximize an accuracy measure summarized using the receiver operating characteristic curve. Under a specific probability model, this leads to the consideration of linear discriminant functions. We incorporate an automated variable selection approach using LASSO. An equivalence between LASSO estimation with support vector machines allows for model fitting using standard software. We apply the proposed method to simulated data as well as data from a recently published prostate cancer study.

Journal Article↗

PubMed2004

Complete isolation of left atrium surrounding the pulmonary veins: new insights from the double-Lasso technique in paroxysmal atrial fibrillation.

BACKGROUND: Paroxysmal atrial fibrillation (PAF) can be eliminated with continuous circular lesions (CCLs) around the pulmonary veins (PVs), but it is unclear whether all PVs are completely isolated. METHODS AND RESULTS: Forty-one patients with symptomatic PAF underwent 3D mapping, and all PV ostia were marked on the 3D map based on venography. Irrigated radiofrequency energy was applied at a distance from the PV ostia guided by 2 Lasso catheters placed within the ipsilateral superior and inferior PVs. The mean radiofrequency duration was 1550+/-511 seconds for left-sided PVs and 1512+/-506 seconds for right-sided PVs. After isolation, automatic activity was observed in the right-sided PVs in 87.8% and in the left-sided PVs in 80.5%. During the procedure, a spontaneous or induced PV tachycardia (PVT) with a cycle length of 189+/-29 ms was observed in 19 patients. During a mean follow-up of 6 months, atrial tachyarrhythmias recurred in 10 patients. Nine patients underwent a repeat procedure. Conduction gaps in the left CCL in 9 patients and in the right CCL in 2 patients were closed during the second procedure. A spontaneous PVT with a cycle length of 212+/-44 ms was demonstrated in 7 of 9 patients, even though no PVT had been observed in 6 of these 7 patients during the first procedure. No AF recurred in 39 patients after PV isolation during follow-up. CONCLUSIONS: Automatic activity and fast tachycardia within the PVs could reflect an arrhythmogenic substrate in patients with PAF, which could be eliminated by isolating all PVs with CCLs guided by 3D mapping and the double-Lasso technique in the majority of patients.

Adenosine↗