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1.
Biochim Biophys Acta Biomembr ; 1866(7): 184371, 2024 Oct.
Article in English | MEDLINE | ID: mdl-39025256

ABSTRACT

Septins are cytoskeletal proteins and their interaction with membranes is crucial for their role in various cellular processes. Septins have polybasic regions (PB1 and PB2) which are important for lipid interaction. Earlier, we and others have highlighted the role of the septin C-terminal domain (CTD) to membrane interaction. However, detailed information on residues/group of residues important for such feature is lacking. In this study, we investigate the lipid-binding profile of Schistosoma mansoni Septin10 (SmSEPT10) using PIP strip and Langmuir monolayer adsorption assays. Our findings highlight the CTD as the primary domain responsible for lipid interaction in SmSEPT10, showing binding to phosphatidylinositol phosphates. SmSEPT10 CTD contains a conserved polybasic region (PB3) present in both animals and fungi septins, and a Lys (K367) within its putative amphipathic helix (AH) that we demonstrate as important for lipid binding. PB3 deletion or mutation of this Lys (K367A) strongly impairs lipid interaction. Remarkably, we observe that the AH within a construct lacking the final 43 amino acid residues is insufficient for lipid binding. Furthermore, we investigate the homocomplex formed by SmSEPT10 CTD in solution by cross-linking experiments, CD spectroscopy, SEC-MALS and SEC-SAXS. Taken together, our studies define the lipid-binding region in SmSEPT10 and offer insights into the molecular basis of septin-membrane binding. This information is particularly relevant for less-studied non-human septins, such as SmSEPT10.


Subject(s)
Schistosoma mansoni , Septins , Schistosoma mansoni/genetics , Schistosoma mansoni/metabolism , Septins/metabolism , Septins/chemistry , Septins/genetics , Animals , Protein Binding , Protein Domains , Amino Acid Motifs , Amino Acid Sequence , Helminth Proteins/chemistry , Helminth Proteins/metabolism , Helminth Proteins/genetics , Lipids/chemistry
2.
Polymers (Basel) ; 16(11)2024 Jun 02.
Article in English | MEDLINE | ID: mdl-38891521

ABSTRACT

N-alkyl-substituted polyacrylamides exhibit a thermal coil-to-globule transition in aqueous solution driven by an increase in hydrophobic interactions with rising temperature. With the aim of understanding the role of N-alkyl substituents in the thermal transition, this study focuses on the molecular interactions underlying the phase transition of poly(N,N-diethylacrylamide-co-N-ethylacrylamide) random copolymers. Poly(N,N-diethylacrylamide) (PDEAm), poly(N-ethylacrylamide) (PNEAm), and their random copolymers were synthesized by free radical polymerization and their chemical structure characterized spectroscopically. It was found that the values of the cloud-point temperature increased with PNEAm content, and particle aggregation processes took place, increasing the negative charge density on their surface. The cloud-point temperature of each copolymer decreased with respect to the theoretical values calculated assuming an absence of interactions. It is attributed to the formation of intra- and interchain hydrogen bonding in aqueous solutions. These interactions favor the formation of more hydrophobic macromolecular segments, thereby promoting the cooperative nature of the transition. These results definitively reveal the dominant mechanism occurring during the phase transition in the aqueous solutions of these copolymers.

3.
J Clin Neurosci ; 123: 47-54, 2024 May.
Article in English | MEDLINE | ID: mdl-38531194

ABSTRACT

BACKGROUND: Endovascular treatment of intracranial aneurysms (EVTIAs) is increasingly popular due to its minimally invasive nature and high success rate. While general anesthesia (GA) has been the historical preference for EVTIAs, there's growing interest in local anesthesia (LA). However, concerns persist about LA safety for EVTIAs. Therefore, we conducted a systematic review and meta-analysis to assess LA safety for EVTIAs. METHODS: Following PRISMA guidelines, we searched PubMed, Embase, and Web of Science databases. Pooled analysis with 95 % confidence intervals (CI) assessed effects, I2 statistics gauged heterogeneity, and a random-effects model was adopted. Conversion to GA, neurological or procedure-related complications, intraoperative intracranial hemorrhagic complications (IIHC), and mortality were assessed. Subanalyses for ruptured and unruptured cases were performed. RESULTS: The analysis included eleven studies, 2,133 patients, and 2,369 EVTIAs under LA. Conversion to GA rate was 1 % (95 %CI: 0 to 2 %). Neurological or procedure-related complications rate was 13 % (95 % CI: 8 % to 17 %). IIHC analysis revealed a rate of 1 % (95 % CI: 1 % to 2 %). The mortality rate was 0 % (95 %CI: 0 % to 0 %). Subanalyses revealed similar rates in ruptured and unruptured subgroups, except for a slightly high rate of complications and IIHC in the ruptured subgroup. CONCLUSION: Findings indicate that EVTIA under LA is safe, with low conversion and mortality rates, even for ruptured aneurysms. Complications rates, also in IIHC rates, are comparable to those reported for GA, emphasizing LA's comparable safety profile in EVTIAs. Considering these promising outcomes, the decision to opt for the LA approach emerges as meaningful and well-suited for the endovascular treatment of aneurysms. Beyond its safety, LA introduces inherent supplementary advantages, including shortened hospitalization periods, cost-effectiveness, and an expedited patient recovery process.


Subject(s)
Anesthesia, Local , Endovascular Procedures , Intracranial Aneurysm , Humans , Endovascular Procedures/adverse effects , Endovascular Procedures/methods , Intracranial Aneurysm/surgery , Anesthesia, Local/methods
4.
J Neurointerv Surg ; 2024 Mar 19.
Article in English | MEDLINE | ID: mdl-38503509

ABSTRACT

BACKGROUND: Cerebral aneurysms, especially large and giant aneurysms, pose challenges in neurointerventional surgery. Treatment choices involve clinical presentation, aneurysm details, and global resource variations. Neurointerventional methods, while innovative, may be cost restrictive in certain regions. In public healthcare, cost is crucial, notably in countries like Brazil. This study examines the device specific cost estimation of flow diverters (FD) and traditional stent assisted coiling (SAC) for large and giant cerebral aneurysms, providing insights into optimizing neurosurgical interventions within the Brazilian public health system's unique challenges. METHODS: A comprehensive retrospective analysis was conducted at our medical center of cases of large and giant aneurysms treated between 2013 and 2023. Determination of the estimated number of coils for aneurysms previously treated with FDs at our center was made, with the cost of each case, and the difference between both treatments was calculated. RESULTS: We investigated the profiles of 77 patients: 40 had large aneurysms (51.9%) and 37 had giant aneurysms (48.1%). Large aneurysms had a mean cost difference of US$274 (standard deviation (SD) $2071), underscoring the device specific cost estimation of FDs over SAC in their treatment. For giant aneurysms, the mean cost difference increased to $6396 (SD $2694), indicating FDs as the more economically sound choice. CONCLUSION: Our study indicated that, for the treatment of giant aneurysms and some large aneurysms, the FD intervention was more economical than SAC.

5.
J Vasc Surg Cases Innov Tech ; 10(2): 101397, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38304295

ABSTRACT

Vascular complications after arthroscopy are rare and generally present as transient paresthesia most likely due to nervous injury or vasospasm. Rare cases of genicular artery injuries can occur and generally involve the medial genicular artery due to proximity to the right arthroscopic knee hook. This case, however, represents a rare lateral inferior genicular artery injury resulting in a symptomatic pseudoaneurysm. In addition, during the workup, the best visualization of the pseudoaneurysm was possible using duplex ultrasound. The diagnostic information seen on ultrasound was paramount and superseded the findings from conventional angiography and computed tomography angiography, both of which were nonspecific. In brief, this case not only highlights a rare surgical complication but also emphasizes the importance of duplex ultrasound compared with angiography and computed tomography in the workup of pseudoaneurysms.

6.
Foods ; 12(13)2023 Jun 29.
Article in English | MEDLINE | ID: mdl-37444278

ABSTRACT

A Helmholtz-type electromagnetic emission device, which uses an oscillating magnetic field (OMF), with potential applications in biotechnological research, was built and validated. The coils were connected to an alternating current (AC) generator to generate a 0.5 to 110 mT field at their center. OMF measurements were performed with a Hall effect sensor with a digital signal connection (Arduino nano) and data output to a PC using LabVIEW v2017SP1 software. The fermentation process of the cocoa bean variety CCN 51, exposed to four levels of OMF density for 60 min (0, 5, 40, and 80 mT/60 min), was analyzed. Different variables of the grain fermentation process were evaluated over six days. The ANOVA test probed the device's linearity, accuracy, precision, repeatability, reliability, and robustness. Moreover, CCN 51 cocoa beans' EMF-exposure effect was evaluated under different OMF densities for 60 min. The results show the validity of the equipment under working conditions and the impact of EMF (electromagnetic fields) on the yield, deformation, and pH of cocoa beans. Thus, we concluded that the operation of the prototype is valid for use in biotechnological studies.

7.
Clinics (Sao Paulo) ; 78: 100202, 2023.
Article in English | MEDLINE | ID: mdl-37130488

ABSTRACT

PURPOSES: Braided and laser-cut stents both are efficacious and safe for coiling intracranial aneurysms. The study aimed to compare outcomes following braided stent-assisted coil embolization versus laser engraved stent-assisted coil embolization in 266 patients who were diagnosed with unruptured intracranial aneurysms of different types and locations. METHODS: Patients with unruptured complex intracranial aneurysms underwent braided (BSE cohort, n = 125) or laser engraved (LSE cohort, n = 141) stent-assisted embolization. RESULTS: The deployment success rate was higher for patients of the LSE cohort than those of the BSE cohort (140 [99%] vs. 117 [94%], p = 0.0142). Seventy-one (fifty-seven percentages) and 73 (52%) were coil embolization procedure success rates of the BSE and the LSE cohorts. Periprocedural intracranial hemorrhage was higher in patients of the BSE cohort than those of the LSE cohort (8 [6%] vs. 1 [1%], p = 0.0142). Four (three percentages) patients from the LSE cohort and 3 (2%) patients from the BSE cohort had in-stent thrombosis during embolization. Permanent morbidities were higher in patients of the LSE cohort than those of the BSE cohort (8 [6%] vs. 1 [1%], p = 0.0389). Higher successful procedures (76% vs. 68%) and fewer postprocedural intracranial hemorrhage (0% vs. 5%) and mortality (0% vs. 5%) were reported for patients of the BSE cohort in posterior circulation aneurysmal location than those of the LSE cohort. Laser engraved stent has fewer problems with deployment and may have better periprocedural and follow-up outcomes after embolization. CONCLUSIONS: Braided stent-assisted embolization should be preferred when the aneurysm is present in the posterior circulation.


Subject(s)
Intracranial Aneurysm , Humans , Intracranial Aneurysm/surgery , Retrospective Studies , Blood Vessel Prosthesis , Stents , Intracranial Hemorrhages , Treatment Outcome
8.
Clin Transl Oncol ; 25(10): 2931-2937, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37020165

ABSTRACT

PURPOSE: To explore the application value of CT-guided localization using a coil in combination with medical adhesive in sublobar resection. METHODS: The clinical data of 90 patients who had small pulmonary nodules and received thoracoscopic sublobar resection during the period from September 2021 to October 2022 in the Department of Thoracic Surgery, Juxian People's Hospital, Shandong Province, were retrospectively analyzed. RESULTS: The diameters of 95 pulmonary nodules in the 90 patients in the whole group ranged from 0.40 to 1.24 cm, and their distances from the visceral pleura ranged from 0.51 to 2.15 cm. In these patients, percutaneous lung puncture was successfully performed under local anesthesia, through which coils were implanted in the nodules and medical adhesive was injected around the nodules, with a success rate of localization of 100%. Localization complications included 10 cases of asymptomatic pneumothorax, 9 cases of intrapulmonary hemorrhage, 5 cases of severe pain, and 1 case of pleural reaction, all of which required no special treatment. After preoperative localization, the success rate of resection of pulmonary nodules was 100%, and sufficient surgical margins were obtained. CONCLUSION: CT-guided localization using a coil in combination with medical adhesive is a safe, effective, and simple localization method that can meet the requirements of thoracic surgeons for intraoperative localization; for small pulmonary nodules, especially those small-sized and deep-located ground-glass nodules containing few solid mass, this method has important clinical application value, which is a preoperative localization technique worthy of wide application in clinical practice.


Subject(s)
Lung Neoplasms , Multiple Pulmonary Nodules , Solitary Pulmonary Nodule , Humans , Lung Neoplasms/diagnostic imaging , Lung Neoplasms/surgery , Retrospective Studies , Adhesives , Multiple Pulmonary Nodules/surgery , Tomography, X-Ray Computed/methods
9.
J Neurointerv Surg ; 15(8): 781-786, 2023 Aug.
Article in English | MEDLINE | ID: mdl-35831177

ABSTRACT

BACKGROUND: Aneurysm recurrence remains a challenge when coiling cerebral aneurysms. Development of next generation coils has focused on accelerating thrombus maturation and increasing coil packing density. Ultra low density shape memory polymer is a novel embolic material designed for this purpose. The polymer is crimped over a platinum-tungsten coil for catheter delivery and self-expands to a predefined volume on contact with blood. METHODS: This prospective study in humans evaluated aneurysms 5-16 mm (inclusive) in diameter that were indicated for endovascular coil embolization. At least 70% coil volume was required to be shape memory polymer coils. Patients were followed-up according to standard of care for 12 months. RESULTS: Nine patients (89% women, mean age 55.8±11.7 years) were treated with shape memory polymer coils and completed 12 months of follow-up. Aneurysms were all unruptured and were in the ophthalmic segment of the internal carotid artery (n=7), posterior communicating artery, and anterior cerebral artery A1-A2 segment. Aneurysms were a mean of 7.8±2.9 mm in diameter (range 5.2-14.9 mm). The mean packing density based on unexpanded polymer was 17±6%. Packing density based on expanded polymer was 43±13%. At 12 months, no recurrence had occurred, and a Raymond-Roy occlusion classification of 1 (n=5) or 2 (n=4) was observed. No serious adverse events related to the study device occurred over the 12 months after the procedure. CONCLUSIONS: Shape memory polymer coils were safe and effective in treating intracranial aneurysms over 12 months in this first study in human subjects.


Subject(s)
Embolization, Therapeutic , Intracranial Aneurysm , Humans , Female , Adult , Middle Aged , Aged , Male , Intracranial Aneurysm/diagnostic imaging , Intracranial Aneurysm/therapy , Intracranial Aneurysm/etiology , Follow-Up Studies , Prospective Studies , Chile , Treatment Outcome , Embolization, Therapeutic/methods , Polymers , Retrospective Studies
10.
Psychiatry Res ; 320: 115036, 2023 02.
Article in English | MEDLINE | ID: mdl-36586377

ABSTRACT

Activation of the insula is found in all anxiety-related disorders and increased insular-prefrontal cortex (PFC) functional connectivity is associated with reduced anxiety. In this study, the combined stimulation of the insula and PFC using the dTMS H4 (insula+LPFC) and H2 (PFC) coils were used to reduce anxiety in 13 subjects experiencing occupational stress, and 55 participants suffering from generalized anxiety disorder (GAD). The combined HF stimulation of the insula and PFC significantly decreased anxiety scores according to the HARS, CAS, and STAI anxiety scales, leading to a reduction in anxiety according to HARS of 88.7% and 70.7% in participants with occupational stress and the clinical sample of participants diagnosed with GAD, respectively. The findings suggest that the prefrontal-insular axis is critical for the regulation of anxiety and its stimulation can be used for the treatment of anxiety in people suffering from occupational stress and GAD.


Subject(s)
Magnetic Resonance Imaging , Occupational Stress , Humans , Anxiety Disorders/therapy , Prefrontal Cortex/diagnostic imaging , Anxiety/therapy
11.
Clinics ; Clinics;78: 100202, 2023. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1439915

ABSTRACT

Abstract Purposes: Braided and laser-cut stents both are efficacious and safe for coiling intracranial aneurysms. The study aimed to compare outcomes following braided stent-assisted coil embolization versus laser engraved stent-assisted coil embolization in 266 patients who were diagnosed with unruptured intracranial aneurysms of different types and locations. Methods: Patients with unruptured complex intracranial aneurysms underwent braided (BSE cohort, n = 125) or laser engraved (LSE cohort, n = 141) stent-assisted embolization. Results: The deployment success rate was higher for patients of the LSE cohort than those of the BSE cohort (140 [99%] vs. 117 [94%], p = 0.0142). Seventy-one (fifty-seven percentages) and 73 (52%) were coil embolization procedure success rates of the BSE and the LSE cohorts. Periprocedural intracranial hemorrhage was higher in patients of the BSE cohort than those of the LSE cohort (8 [6%] vs. 1 [1%], p = 0.0142). Four (three percentages) patients from the LSE cohort and 3 (2%) patients from the BSE cohort had in-stent thrombosis during embolization. Permanent morbidities were higher in patients of the LSE cohort than those of the BSE cohort (8 [6%] vs. 1 [1%], p = 0.0389). Higher successful procedures (76% vs. 68%) and fewer postprocedural intracranial hemorrhage (0% vs. 5%) and mortality (0% vs. 5%) were reported for patients of the BSE cohort in posterior circulation aneurysmal location than those of the LSE cohort. Laser engraved stent has fewer problems with deployment and may have better periprocedural and follow-up outcomes after embolization. Conclusions: Braided stent-assisted embolization should be preferred when the aneurysm is present in the posterior circulation.

12.
Sensors (Basel) ; 22(21)2022 Oct 26.
Article in English | MEDLINE | ID: mdl-36365882

ABSTRACT

In this work, a wireless communication system based on magnetic coils for underwater vehicles is presented. Firstly, the mathematical model of magnetic field induction using magnetic coils is discussed. Then, a description of the proposed communication system is presented, including the main components of the transmitter and receiver module. The experimental results show that due to the properties of the magnetic field, the proposed communication system can work properly in different environments such as air or water with the same efficiency. Underwater tests were carried out in different water circumstances: varying the temperature in a range from 10 °C to 35 °C, varying concentrations of clay in a range from 0% to 10%, and varying the salinity concentration in a range from 1000 ppm ( parts per million) to 35,000 ppm. It was observed that these conditions do not affect the information transfer. Finally, the advantages of using the proposed system compared to existing submarine communication systems are discussed.

13.
Brain Sci ; 12(9)2022 Sep 09.
Article in English | MEDLINE | ID: mdl-36138954

ABSTRACT

The technology for transcranial magnetic stimulation (TMS) has significantly changed over the years, with important improvements in the signal generators, the coils, the positioning systems, and the software for modeling, optimization, and therapy planning. In this systematic literature review (SLR), the evolution of each component of TMS technology is presented and analyzed to assess the limitations to overcome. This SLR was carried out following the PRISMA 2020 statement. Published articles of TMS were searched for in four databases (Web of Science, PubMed, Scopus, IEEE). Conference papers and other reviews were excluded. Records were filtered using terms about TMS technology with a semi-automatic software; articles that did not present new technology developments were excluded manually. After this screening, 101 records were included, with 19 articles proposing new stimulator designs (18.8%), 46 presenting or adapting coils (45.5%), 18 proposing systems for coil placement (17.8%), and 43 implementing algorithms for coil optimization (42.6%). The articles were blindly classified by the authors to reduce the risk of bias. However, our results could have been influenced by our research interests, which would affect conclusions for applications in psychiatric and neurological diseases. Our analysis indicates that more emphasis should be placed on optimizing the current technology with a special focus on the experimental validation of models. With this review, we expect to establish the base for future TMS technological developments.

14.
J Vasc Bras ; 21: e20210223, 2022.
Article in English | MEDLINE | ID: mdl-35911476

ABSTRACT

Internal thoracic artery aneurysms (ITAAs) are rare with wide variation in clinical presentation and a high risk of rupture. Endovascular techniques are increasingly being used for treatment of such aneurysms over surgical repair in recent times. A 34-year-old male presented with progressive swelling of the right anterior chest wall for 2 weeks and was diagnosed with right internal thoracic artery aneurysm with contained rupture. He underwent successful endovascular repair with coil embolization of ruptured right ITAA. Post intervention computed tomography (CT) angiography confirmed sealing of the ruptured aneurysm with no residual filling of the sac. At six months follow-up he is doing well with complete resolution of hematoma. This case demonstrates that an endovascular approach with coil embolization is a feasible and safe option for treating the rare ruptured ITAAs.


Os aneurismas da artéria torácica interna (ITAAs) são raros, com ampla variação na apresentação clínica e alto risco de ruptura. As técnicas endovasculares têm sido cada vez mais utilizadas para o tratamento desses aneurismas em relação ao reparo cirúrgico. Um homem de 34 anos de idade apresentou edema progressivo da parede torácica anterior direita por 2 semanas e foi diagnosticado com aneurisma da artéria mamária interna direita com ruptura contida. Ele foi submetido a reparo endovascular bem-sucedido, com embolização de ITAA direito roto. A angiotomografia computadorizada (angioTC) pós-intervenção confirmou o selamento do aneurisma rompido, sem enchimento residual do saco. No seguimento de 6 meses, ele estava bem, com resolução completa do hematoma. Este caso demonstra que a abordagem endovascular com embolização com molas é uma opção viável e segura no tratamento dos raros ITAAs rotos.

15.
J. Vasc. Bras. (Online) ; J. vasc. bras;21: e20210223, 2022. graf
Article in English | LILACS | ID: biblio-1386119

ABSTRACT

Abstract Internal thoracic artery aneurysms (ITAAs) are rare with wide variation in clinical presentation and a high risk of rupture. Endovascular techniques are increasingly being used for treatment of such aneurysms over surgical repair in recent times. A 34-year-old male presented with progressive swelling of the right anterior chest wall for 2 weeks and was diagnosed with right internal thoracic artery aneurysm with contained rupture. He underwent successful endovascular repair with coil embolization of ruptured right ITAA. Post intervention computed tomography (CT) angiography confirmed sealing of the ruptured aneurysm with no residual filling of the sac. At six months follow-up he is doing well with complete resolution of hematoma. This case demonstrates that an endovascular approach with coil embolization is a feasible and safe option for treating the rare ruptured ITAAs.


Resumo Os aneurismas da artéria torácica interna (ITAAs) são raros, com ampla variação na apresentação clínica e alto risco de ruptura. As técnicas endovasculares têm sido cada vez mais utilizadas para o tratamento desses aneurismas em relação ao reparo cirúrgico. Um homem de 34 anos de idade apresentou edema progressivo da parede torácica anterior direita por 2 semanas e foi diagnosticado com aneurisma da artéria mamária interna direita com ruptura contida. Ele foi submetido a reparo endovascular bem-sucedido, com embolização de ITAA direito roto. A angiotomografia computadorizada (angioTC) pós-intervenção confirmou o selamento do aneurisma rompido, sem enchimento residual do saco. No seguimento de 6 meses, ele estava bem, com resolução completa do hematoma. Este caso demonstra que a abordagem endovascular com embolização com molas é uma opção viável e segura no tratamento dos raros ITAAs rotos.


Subject(s)
Humans , Male , Adult , Aneurysm, Ruptured/therapy , Embolization, Therapeutic , Endovascular Procedures , Mammary Arteries/diagnostic imaging , Computed Tomography Angiography
16.
Front Cell Dev Biol ; 9: 765085, 2021.
Article in English | MEDLINE | ID: mdl-34869357

ABSTRACT

In order to fully understand any complex biochemical system from a mechanistic point of view, it is necessary to have access to the three-dimensional structures of the molecular components involved. Septins and their oligomers, filaments and higher-order complexes are no exception. Indeed, the spontaneous recruitment of different septin monomers to specific positions along a filament represents a fascinating example of subtle molecular recognition. Over the last few years, the amount of structural information available about these important cytoskeletal proteins has increased dramatically. This has allowed for a more detailed description of their individual domains and the different interfaces formed between them, which are the basis for stabilizing higher-order structures such as hexamers, octamers and fully formed filaments. The flexibility of these structures and the plasticity of the individual interfaces have also begun to be understood. Furthermore, recently, light has been shed on how filaments may bundle into higher-order structures by the formation of antiparallel coiled coils involving the C-terminal domains. Nevertheless, even with these advances, there is still some way to go before we fully understand how the structure and dynamics of septin assemblies are related to their physiological roles, including their interactions with biological membranes and other cytoskeletal components. In this review, we aim to bring together the various strands of structural evidence currently available into a more coherent picture. Although it would be an exaggeration to say that this is complete, recent progress seems to suggest that headway is being made in that direction.

17.
Materials (Basel) ; 14(15)2021 Jul 31.
Article in English | MEDLINE | ID: mdl-34361473

ABSTRACT

Moisture distribution in cement-based materials is important from the durability point of view. In the present study, a portable three-magnet array with an elliptical surface radio frequency coil was used to undertake magnetic resonance measurements of moisture content in ordinary Portland cement mortar and concrete samples. Measurements along the length of the samples during capillary water absorption produced moisture content profiles that were compared with reference profiles acquired using a magnetic resonance imaging instrument. Profiles obtained with the three-magnet array were similar in shape and in penetration depth to those acquired with magnetic resonance imaging. The correlation coefficient between the moisture content measured with both techniques was r2 = 0.97. Similar values of saturated permeability of the mortars with identical w/c ratio were computed with the Hydrus 1D software based on the moisture content profiles. Additionally, inverse Laplace transformation of the signal decays provided the water-filled pore size distribution in saturated and unsaturated regions of the samples. The three-magnet array was successfully used to acquire nuclear magnetic resonance signal from a concrete sample, which was not possible with the magnetic resonance imaging instrument using the single-point imaging technique.

18.
J Vasc Surg Cases Innov Tech ; 7(2): 364-367, 2021 Jun.
Article in English | MEDLINE | ID: mdl-34136727

ABSTRACT

Tuberous sclerosis complex (TSC) is an autosomal dominant multisystem neurocutaneous genetic condition. It is characterized by TSC-associated neuropsychiatric disorders, epilepsy, tumors, and angiomyolipoma in multiple organs, such as the skin, lungs, and kidneys. TSC is also associated with the development of aneurysms of the medium and large arteries, including the renal arteries. This condition will usually be diagnosed early in life, and active surveillance is required of tumor and aneurysm growth to prevent life-threatening events. We have presented the case of a 41-year-old patient with TSC that had not been previously diagnosed. The patient had presented with retroperitoneal hematoma secondary to the rupture of two left renal artery branch aneurysms that had likely developed within the angiomyolipoma.

19.
J Mol Biol ; 433(9): 166889, 2021 04 30.
Article in English | MEDLINE | ID: mdl-33639214

ABSTRACT

Septins are an example of subtle molecular recognition whereby different paralogues must correctly assemble into functional filaments important for essential cellular events such as cytokinesis. Most possess C-terminal domains capable of forming coiled coils which are believed to be involved in filament formation and bundling. Here, we report an integrated structural approach which aims to unravel their architectural diversity and in so doing provide direct structural information for the coiled-coil regions of five human septins. Unexpectedly, we encounter dimeric structures presenting both parallel and antiparallel arrangements which are in consonance with molecular modelling suggesting that both are energetically accessible. These sequences therefore code for two metastable states of different orientations which employ different but overlapping interfaces. The antiparallel structures present a mixed coiled-coil interface, one side of which is dominated by a continuous chain of core hydrophilic residues. This unusual type of coiled coil could be used to expand the toolkit currently available to the protein engineer for the design of previously unforeseen coiled-coil based assemblies. Within a physiological context, our data provide the first atomic details related to the assumption that the parallel orientation is likely formed between septin monomers from the same filament whilst antiparallelism may participate in the widely described interfilament cross bridges necessary for higher order structures and thereby septin function.


Subject(s)
Septins/chemistry , Crystallography, X-Ray , Humans , Hydrophobic and Hydrophilic Interactions , Models, Molecular , Nuclear Magnetic Resonance, Biomolecular , Protein Multimerization , Protein Stability , Protein Structure, Secondary , Septins/metabolism , Solutions , Thermodynamics
20.
Parasitol Res ; 120(3): 1067-1076, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33515065

ABSTRACT

Giardia intestinalis is a human parasite that causes a diarrheal disease in developing countries. G. intestinalis has a cytoskeleton (CSK) composed of microtubules and microfilaments, and the Giardia genome does not code for the canonical CSK-binding proteins described in other eukaryotic cells. To identify candidate actin and tubulin cross-linking proteins, we performed a BLAST analysis of the Giardia genome using a spectraplakins consensus sequence as a query. Based on the highest BLAST score, we selected a 259-kDa sequence designated as a cytoskeleton linker protein (CLP259). The sequence was cloned in three fragments and characterized by immunoprecipitation, confocal microscopy, and mass spectrometry (MS). CLP259 was located in the cytoplasm in the form of clusters of thick rods and colocalized with actin at numerous sites and with tubulin in the median body. Immunoprecipitation followed by mass spectrometry revealed that CLP259 interacts with structural proteins such as giardins, SALP-1, axonemal, and eight coiled-coils. The vesicular traffic proteins detected were Mu adaptin, Vacuolar ATP synthase subunit B, Bip, Sec61 alpha, NSF, AP complex subunit beta, and dynamin. These results indicate that CLP259 in trophozoites is a CSK linker protein for actin and tubulin and could act as a scaffold protein driving vesicular traffic.


Subject(s)
Actins/metabolism , Giardia lamblia/metabolism , Plakins/metabolism , Tubulin/metabolism , Actins/chemistry , Amino Acid Sequence , Animals , Ankyrins/chemistry , Base Sequence , Blotting, Western , Computational Biology , Consensus Sequence , Cytoplasm/chemistry , Cytoskeleton/chemistry , Cytoskeleton/physiology , Cytoskeleton/ultrastructure , Dynamins/analysis , Female , Fluorescent Antibody Technique , Giardia lamblia/chemistry , Giardia lamblia/ultrastructure , Humans , Immunoprecipitation , Mice , Mice, Inbred BALB C , Microscopy, Confocal , Plakins/chemistry , Sequence Alignment , Tubulin/chemistry
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