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At least 19 recordsLinked to original sources
PubMed2026

Long-term outcomes of surgical correction of ventral penile curvature in children: Patient-reported measures, surgical results, and decisional regret.

INTRODUCTION: There is a dearth of data on long-term outcomes, including patient-reported outcomes (PROMs), decisional regret, and complication rates for surgical correction of isolated ventral penile curvature in childhood. PATIENTS AND METHODS: Twenty-six children treated for ventral curvature between 1993 and 2008 were identified; 24 met inclusion criteria (isolated ventral curvature without hypospadias or need for urethral reconstruction). Surgical correction consisted of degloving alone or degloving with Nesbit-like dorsal plication when residual curvature >20° persisted after degloving. PROMs were collected via pre-mailed validated questionnaires after puberty: Danish Prostatic Symptom Score (DAN-PSS) for LUTS, Erection Hardness Score (EHS) for erectile function, Penile Perception Score (PPS) for cosmetic perception, and items assessing decisional regret and perceived appropriateness of surgical timing. RESULTS: Curvature was corrected intraoperatively in all 24 patients. Twelve underwent degloving alone and 12 required additional dorsal plication. During long-term follow-up (median 14.2 years), one patient (4%) underwent re-operation for residual curvature, and three (13%) underwent cosmetic revisions; two (8%) underwent cystoscopy for flow concerns. 71% returned PROMs at a median age of 16.2 years. LUTS were uncommon, with low bother scores. Erectile function was favorable: 87% (13/15) reported EHS 4 and 93% (14/15) reported ejaculation. Cosmetic outcomes were favorable, with PPS dissatisfaction rates comparable to controls. Two patients reported dissatisfaction with overall appearance, and one with residual subjective curvature. No patient expressed decisional regret, and 88% felt timing of surgery was appropriate. CONCLUSION: Early surgical correction of isolated ventral penile curvature using degloving with or without dorsal plication provided durable anatomical correction and favorable long-term functional and cosmetic outcomes. These findings support early intervention as an effective approach with sustained patient-perceived benefits.

Humans↗
PubMed2026

Postoperative Curvature Loss in Three-Level Anterior Cervical Discectomy and Fusion With Zero-Profile Device.

PURPOSE: Cervical curvature loss is a frequent complication following 3-level anterior cervical discectomy and fusion (ACDF) using a Zero-Profile device. Consequently, the capacity of this device to maintain cervical sagittal alignment in 3-level ACDF remains highly controversial. This study aimed to identify potential predictors for postoperative curvature loss (PCL) and evaluate its impact on clinical outcomes. METHODS: A total of 113 patients who underwent ACDF for 3-level cervical degenerative disc disease (CDDD) between January 2021 and December 2023 were retrospectively reviewed. Demographic data, radiological parameters, and clinical outcomes were analyzed. Radiographic measures included cervical curvature, T1 slope, C2-7 sagittal vertical axis, and titanium plate and endplate (TPE) distance. Clinical outcomes were assessed using the Visual Analog Scale (VAS), Neck Disability Index (NDI), and Japanese Orthopaedic Association (JOA) scores. Statistical analyses were performed using paired and independent t-tests, as well as Pearson correlation coefficients. RESULTS: The average curvature loss was 6.82&#xb0; from 1&#x2009;week postoperatively to the final follow-up (p&#x2009;<&#x2009;0.001). However, the final curvature (11.65&#xb0;) was maintained, representing a 4.33&#xb0; improvement compared to preoperative values. Significant correlations were observed between PCL and preoperative curvature (r&#x2009;=&#x2009;-0.368, p&#x2009;=&#x2009;0.013), preoperative T1 slope (r&#x2009;=&#x2009;-0.546, p&#x2009;<&#x2009;0.001), &#x2206;T1 slope (r&#x2009;=&#x2009;0.443, p&#x2009;=&#x2009;0.002), and &#x2206;TPE distance (r&#x2009;=&#x2009;0.417, p&#x2009;=&#x2009;0.004). PCL did not correlate with Japanese Orthopaedic Association (JOA) scores or arm VAS scores at the final follow-up. Nevertheless, patients with a PCL&#x2009;&#x2265;&#x2009;6&#xb0; exhibited significantly higher neck VAS (p&#x2009;=&#x2009;0.028) and NDI scores (p&#x2009;=&#x2009;0.041). CONCLUSION: Although contiguous 3-level ACDF with a Zero-Profile device may result in PCL, it preserves an improved cervical lordosis compared to the preoperative baseline. Low preoperative curvature and a low preoperative T1 slope are potentially predictive factors for PCL. Postoperative changes in TPE distance and T1 slope are significantly associated with PCL, suggesting a potential biomechanical link that requires direct validation. Furthermore, PCL may lead to higher neck VAS and NDI scores. Consequently, the Zero-Profile device may require careful consideration in 3-level CDDD patients presenting with low preoperative curvature and a low T1 slope. Importantly, the 6&#xb0; PCL threshold identified is preliminary and requires prospective validation before clinical application.

Humans↗
PubMed2026

Cell-body curvature reduces stall frequency to enhance Vibrio cholerae swimming and chemotaxis through hydrogels.

The swimming motility of the bacterial pathogen Vibrio cholerae is a virulence factor that aids in breaching the mucus layer. V. cholerae has a curved cell shape, and previous work demonstrated that loss of curvature decreases infectivity. Here, we investigate the mechanism by which curvature affects single-cell motility. We compared the chemotactic performance of wild-type curved cells and straight mutants. The two exhibit similar swimming properties in liquid and viscous solutions but differ significantly in mucus-mimicking hydrogels, where curved cells demonstrate an 86% increase in chemotactic drift. Trajectory analysis indicates comparable swimming speeds, but straight mutants experience more frequent stalls, reducing total swimming time. Stalls further reduce chemotactic performance by imposing an average reorientation down the chemical gradient, regardless of cell shape. Coarse-grained molecular dynamics simulations corroborate these results across intestinal mucus hydrogel stiffnesses and identify an optimal curvature for movement through hydrogel-like meshes, close to the pathogen's median curvature. These findings highlight cell shape's role in pathogenicity and the need to study bacterial behaviors under conditions more closely mimicking the host environment.

Vibrio cholerae↗
PubMed1979

[Cancer of the greater curvature of the stomach].

The analysis of 102 observations indicated the clinico-roentgenological features of cancer of the greater curvature of the stomach, thus enabling the possibilities of a roentgenological method of examination to be ascertained in the complex of methods for examining patients with the pathology involved. It was noted that in cancer of the larger curvature of the stomach the character of the lesion is not infrequently masked by the symptoms observed in ulcerous disease, chronic gastritis or Menetrie disease. Accessory methods of roentgenodiagnosis: pneumogastrography, double and triple contrasting technic contribute to pinpointing the true character of the process. Application of the mentioned technics allowed the precise diagnosis to be established in 87.2% of cases. When using fibrogastroscopy the correct diagnosis was made in 86.5% of patients. Use of the complex examination allowed the precise preoperative diagnosis in 92.1%. Some problems of the differential diagnosis between cancer of the larger curvature of the stomach and ulcerous gastric disease are discussed.

Adolescent↗
PubMed2025

Rapid screening and identification of genes involved in bacterial extracellular membrane vesicle production using a curvature-sensing peptide.

Bacteria secrete extracellular membrane vesicles (EMVs). Physiological functions and biotechnological applications of these lipid nanoparticles have been attracting significant attention. However, the details of the molecular basis of EMV biogenesis have not yet been fully elucidated. In our previous work, an N-terminus-substituted FAAV peptide labeled with nitrobenzoxadiazole (NBD; nFAAV5-NBD) was developed. This peptide can sense the curvature of a lipid bilayer and selectively bind to EMVs even in the presence of cells. Here, we applied nFAAV5-NBD to a genome-wide screening of hyper- and hypo-vesiculation transposon mutants of a Gram-negative bacterium, Shewanella vesiculosa HM13, to identify the genes involved in EMV production. We analyzed the transposon insertion sites in hyper- and hypo-vesiculation mutants and identified 16 and six genes, respectively, with a transposon inserted within or near them. Targeted gene-disrupted mutants of the identified genes showed that the lack of putative dipeptidyl carboxypeptidase, glutamate synthase &#x3b2;-subunit, LapG protease, metallohydrolase, RNA polymerase sigma-54 factor, inactive transglutaminase, PepSY domain-containing protein, and Rhs-family protein caused EMV overproduction. On the other hand, disruption of the genes encoding putative phosphoenolpyruvate synthase, d-hexose-6-phosphate epimerase, NAD-specific glutamate dehydrogenase, and sensory box histidine kinase/response regulator decreased EMV production. This study demonstrates the utility of a novel screening method using a curvature-sensing peptide for mutants with altered EMV productivity and provides information on the genes related to EMV production.IMPORTANCEConventional methods for isolation and quantification of extracellular membrane vesicles (EMVs) are generally time-consuming. nFAAV5-NBD can detect EMVs in the culture without separating EMVs from cells. In situ detection of EMVs using this peptide facilitated screening of the genes related to EMV production. We succeeded in identifying various genes associated with EMV production of Shewanella vesiculosa HM13, which would contribute to the elucidation of bacterial EMV formation mechanisms. Additionally, the hyper-vesiculating mutants obtained in this study would be valuable for EMV applications, such as secreting useful substances as EMV cargoes and producing artificially functionalized EMVs.

Shewanella↗
PubMed1978

Action of phospholipases A2 on phosphatidylcholine bilayers. Effects of the phase transition, bilayer curvature and structural defects.

We examined the action of porcine pancreatic and bee-venom phospholipase A2 towards bilayers of phosphatidylcholine as a function of several physical characteristics of the lipid-water interface. 1. Unsonicated liposomes of dimyristoyl phosphatidylcholine are degraded by both phospholipases in the temperature region of the phase transition only (cf. Op den Kamp et al. (1974) Biochim. Biophys. Acta 345, 253--256 and Op den Kamp et al. (1975) Biochim. Biophys. Acta 406, 169--177). With sonicates the temperature range in which hydrolysis occurs is much wider. This discrepancy between liposomes and sonicates cannot be ascribed entirely to differences in available substrate surface. 2. Below the phase-transition temperature the phospholipases degrade dimyristoyl phosphatidylcholine single-bilayer vesicles with a strongly curved surface much more effectively than larger single-bilayer vesicles with a relatively low degree of curvature. 3. Vesicles composed of egg phosphatidylcholine can be degraded by pancreatic phospholipase A2 at 37 degrees C, provided that the substrate bilayer is strongly curved. The bee-venom enzyme shows a similar, but less pronounced, preference for small substrate vesicles. 4. In a limited temperature region just above the transition temperature of the substrate the action of both phospholipases initially proceeds with a gradually increasing velocity. This stimulation is presumably due to an increase of the transition temperature, effectuated by the products of the phospholipase action. 5. Structural defects in the substrate bilayer, introduced by sonication below the phase-transition temperature (cf. Lawaczeck et al. (1976) Biochim. Biophys. Acta 443, 313--330) facilitate the action of both phospholipases. The results lead to the general conclusion that structural irregularities in the packing of the substrate molecules facilitate the action of phospholipases A2 on phosphatidylcholine bilayers. Within the phase transition and with bilayers containing structural defects these irregularities represent boundaries between separate lipid domains. The stimulatory effect of strong bilayer curvature can be ascribed to an overall perturbation of the lipid packing as well as to a change in the phase-transition temperature.

Animals↗
PubMed1979

New models of cellular control: membrane cytoskeletons, membrane curvature potential, and possible interactions.

The concepts of "membrane cytoskeletons" (proteins attached to the cytoplasmic face of the membrane to give rigidity and control of lateral protein diffusion) and of membrane curvature potential are briefly reviewed. Possible modes of attachment of the membrane cytoskeleton to the bilayer are discussed, and a detailed calculation of possible sources of membrane curvature potential in the red cell is made. The 2 control systems are then used to illustrate possible mechanisms for some cellular processes, such as vesicle formation and release, pseudopod formation, and red cell aging. It is concluded that combination of these concepts allows control mechanisms which appear to act at a distance, or have other unusual systems properties.

Cell Membrane↗
PubMed2025

ORCO: Ollivier-Ricci Curvature-Omics-an unsupervised method for analyzing robustness in biological systems.

MOTIVATION: Although recent advanced sequencing technologies have improved the resolution of genomic and proteomic data to better characterize molecular phenotypes, efficient computational tools to analyze and interpret large-scale omic data are still needed. RESULTS: To address this, we have developed a network-based bioinformatic tool called Ollivier-Ricci curvature for omics (ORCO). ORCO incorporates omics data and a network describing biological relationships between the genes or proteins and computes Ollivier-Ricci curvature (ORC) values for individual interactions. ORC is an edge-based measure that assesses network robustness. It captures functional cooperation in gene signaling using a consistent information-passing measure, which can help investigators identify therapeutic targets and key regulatory modules in biological systems. ORC has identified novel insights in multiple cancer types using genomic data and in neurodevelopmental disorders using brain imaging data. This tool is applicable to any data that can be represented as a network. AVAILABILITY AND IMPLEMENTATION: ORCO is an open-source Python package and is publicly available on GitHub at https://github.com/aksimhal/ORC-Omics.

Software↗
PubMed1979

[Kinetics and load distribution of supported free-end prostheses. IV. Effect of the saddle curvature on the saddle resp. abutment kinetics and the load distribution in prosthesis beds without abutments].

The influence of the saddle curvature on abutment tooth kinetics and abutment tooth stress was studied with unilateral rigid and movable free-end saddle dentures. The results showed that, independent of the length of the saddle and/or of the saddle curvature, considerable horizontal and vertical extrusive abutment tooth stress is present in addition to vertical intrusive abutment tooth stress. The saddle kinetics are basically influenced by the form of the saddle. The kinetics cannot be altered appreciably because of the mechanical characteristics of the connecting elements; it can only be surpressed at the cost of increased pier stress.

Biomechanical Phenomena↗
PubMed1979

A three-dimensional measurement of the human parietal curvature.

The three-dimensional measurement of the parietal curvature in Japanese was accomplished with the use of moiré contourography and the sexual dimorphism was observed in it. Principal component analysis was also carried out and 4 important features of the shape of this bone were abstracted. Those were the degree of the curvature as a whole, lateral swellings, bilateral difference and posterior swelling.

Asian People↗
PubMed1979

A method of correction for curvature and inhomogeneities in computer aided calculation of external beam radiation dose distributions.

This paper deals with the problem of finding the effective pathlength along a ray passing through a patient's outline and internal structure. The pathlength contributes to the correction applied for curvature and inhomogeneities in the computer-aided calculation of external beam radiation dose distributions. The pathlength is found by first determining the intersections of the ray with the contours defining the patient's body and the interior inhomogeneities. From these intersections the geometric length within each contour is obtained. This information is then employed in a treatment planning program for high energy gamma and X-rays and electrons, in which the radiation dose distribution is computed taking into account the actual inhomogeneous tissue structures. Other applications of the techniques described to problems in the field of radiation therapy are briefly discussed.

Computers↗
PubMed1978

Lesser curvature tubular gastroplasty with partial plication for gastroesophageal reflux: manometric and pH-metric postoperative studies.

Thirty-four patients with sliding hiatal hernia, gastroesophageal reflux, or both were treated by lesser curvature gastroplasty with partial gastric plication, using a surgical stapler. Before operation, esophageal manometric studies were performed in 33 patients and during the early postoperative period (1 to 3 months), in 34. The esophageal pH test was performed before operation in 22 patients, shortly after discharge in 27, and later in 30 patients. The clinical results were considered satisfactory in 30 patients (88%) after follow-up ranging from 18 to 33 months (average, 23 months). Before the procedure, the abdominal compression test was positive in 25 of 30 patients (83%). In early postoperative studies it was positive in 1 out of 34 patients (3%), but in the second series of postoperative studies it was positive in 9 out of 32 (28%). After instillation of hydrochloric acid into the stomach, the esophageal pH test was considered positive in 17 out of 22 patients in preoperative studies (77%). In early postoperative studies the test was positive in 3 out of 27 patients (11%) and one year later, in 7 out of 30 (23%). The later postoperative studies showed a higher number of positive reflux tests than the early studies, 28 and 23% positive in manometric and pH tests, respectively.

Esophagogastric Junction↗
PubMed1977

A technique for closure of the lesser curvature of the stomach used in the von Eiselberg-Hofmeister reconstruction after subtotal gastrectomy.

A technique for closing the lesser curvature of the stomach after subtotal gastrectomy has been used in 847 subtotal gastrectomies. In this group, one patient had transient postoperative bleeding and none had anastomotic leakage. The technique is recommended as a simple method of obtaining a secure and hemostatic closure which can be accomplished rapidly and which does not require the use of special instruments or material.

Gastrectomy↗
PubMedDate not supplied

The sites of origin of gastric cancers and ulcers in relation to mucosal junctions and the lesser curvature.

A histological mapping procedure was used to study 32 stomachs bearing small cancers and 23 stomachs bearing ulcers. Over 80 per cent of gastric cancers and peptic ulcers occurred within 2 cm of both a mucosal junction and the lesser curvature. They showed slight differences in their longitudinal relationship to the pyloric junction. There were differential characteristics between the groups of cancers arising at each of the three mucosal junctions. Cancers at the pylorus and cardia were more common in males (M:F--2.6:1) and were predominantly well differentiated, whereas those from the intermediate zone were more common in females (M:F--1:1.8) with a relatively higher proportion of undifferentiated cancers. These and other features suggest that gastric cancers should be subdivided according to the junction of origin.

Female↗
PubMed1978

Reperitonealization and invagination of the lesser curvature of the stomach following proximal gastric vagotomy.

Lesser curve necrosis usually presents as free perforation. A case of large gastric ulcer occurring very shortly after proximal gastric vagotomy (PGV) for a duodenal ulcer that was almost certainly due to ischemic necrosis of the lesser curve is presented here. Reperitonealization and invagination of the lesser curve is recommended following PGV so that, if necrosis occurs, it will take place within the stomach and not into the free peritoneal cavity. This maneuver may also avoid possible vagal reinnervation and the formation of dense adhesions between the stomach and liver.

Duodenal Ulcer↗