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1.
Nat Commun ; 15(1): 838, 2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38287004

RESUMO

Despite groundbreaking advances in the additive manufacturing of polymers, metals, and ceramics, scaled and accurate production of structured carbons remains largely underdeveloped. This work reports a simple method to produce complex carbon materials with very low dimensional shrinkage from printed to carbonized state (less than 4%), using commercially available polypropylene precursors and a fused filament fabrication-based process. The control of macrostructural retention is enabled by the inclusion of fiber fillers regardless of the crosslinking degree of the polypropylene matrix, providing a significant advantage to directly control the density, porosity, and mechanical properties of 3D printed carbons. Using the same printed plastic precursors, different mechanical responses of derived carbons can be obtained, notably from stiff to highly compressible. This report harnesses the power of additive manufacturing for producing carbons with accurately controlled structure and properties, while enabling great opportunities for various applications.

2.
Nat Commun ; 14(1): 639, 2023 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-36746971

RESUMO

The ability to manufacture ordered mesoporous materials using low-cost precursors and scalable processes is essential for unlocking their enormous potential to enable advancement in nanotechnology. While templating-based methods play a central role in the development of mesoporous materials, several limitations exist in conventional system design, including cost, volatile solvent consumption, and attainable pore sizes from commercial templating agents. This work pioneers a new manufacturing platform for producing ordered mesoporous materials through direct pyrolysis of crosslinked thermoplastic elastomer-based block copolymers. Specifically, olefinic majority phases are selectively crosslinked through sulfonation reactions and subsequently converted to carbon, while the minority block can be decomposed to form ordered mesopores. We demonstrate that this process can be extended to different polymer precursors for synthesizing mesoporous polymer, carbon, and silica. Furthermore, the obtained carbons possess large mesopores, sulfur-doped carbon framework, with tailorable pore textures upon varying the precursor identities.

3.
Adv Mater ; 35(17): e2208029, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36763617

RESUMO

Carbon materials are essential to the development of modern society with indispensable use in various applications, such as energy storage and high-performance composites. Despite great progress, on-demand carbon manufacturing with control over 3D macroscopic configuration is still an intractable challenge, hindering their direct use in many areas requiring structured materials and products. This work introduces a simple and scalable method to generate complex, large-scale carbon structures using easily accessible materials and technologies. 3D-printed, commercial polypropylene (PP) parts can be thermally stabilized through cracking-facilitated diffusion and crosslinking. The newly elucidated mechanism from this work allows thick PP parts to yield carbonaceous products with complex structures through a subsequent pyrolysis step. The approach for enabling PP-to-carbon conversion has consistent product yield and controlled dimensional shrinkage. Under optimized processing conditions, these PP-derived carbons exhibit robust mechanical properties and excellent joule heating performance, demonstrated by their versatile use as heating elements. Furthermore, this process can be extended to recycled PP, enabling the conversion of waste plastic materials to value-added products. This work provides an innovative approach to create structured carbon materials with direct access to complex geometry, which can be transformative to, and broadly benefit, many important technological applications.

4.
Radiol Case Rep ; 17(10): 3974-3978, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35991384

RESUMO

Biliary cystadenoma is a very uncommon benign cystic neoplasm involving the liver and the biliary tract. Most common presentations include right upper quadrant pain, nausea, vomiting, obstructive jaundice, and enlarging liver size. It can mimic many more commonly occurring diseases such as hepatic cyst, hepatic abscess, hydatid disease of the liver, and hepatic tuberculosis. Hence it becomes very challenging for physicians to correctly diagnose it due to its rarity and similarity with other conditions. Furthermore, very few pieces of literature guide physicians in correctly identifying the disease. Based on his physical examination and detailed investigation, we present a case report of a 72-year-old female diagnosed with biliary cystadenoma. We hope that this case report will significantly add to the existing literature on this subject.

5.
Rev. med. Risaralda ; 28(1): 138-143, ene.-jun. 2022. tab
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1389150

RESUMO

Resumen Introducción: La presencia de bacterias en semen (bacteriospermia) es una condición patológica asociada con infertilidad y con prevalencia de hasta el 35%. Objetivo: Reportar el caso de un paciente con oligoastenozoospermia manejado en la consulta de infertilidad. Caso: Paciente masculino de 33 años de edad con historia de dificultad para la concepción, antecedente de orquiectomía por torsión testicular a los 16 años, infección por Chlamydia trachomatis a los 20 años. Examen físico normal, ecografía doppler testicular con varicocele izquierdo leve. Espermograma con oligoastenozoospermia y espermocultivo en agar sangre positivo para Streptococcus spp y agar chocolate para Streptococcus spp. Se inició manejo con ampicilina Sulbactam durante 14 días y control a los 3 meses con nuevo espermograma con mejoría marcada de la concentración y la movilidad progresiva espermática. Resultado: La pareja logro un embarazo exitoso con bebe vivo en casa. Conclusión: La colonización bacteriana del semen contribuye a alteraciones de la calidad seminal, por lo tanto, determinar la presencia de bacterias en las parejas infértiles podría ser de utilidad para el mejoramiento de los parámetros seminales y lograr un embarazo exitoso.


Abstract The presence of bacteria in semen -bacteriospermia- is a pathological condition associated with infertility, which presents a prevalence of up to 35%. We describe the successful management during infertility consultation of a patient suffering from oligoasthenozoospermia. A 33-year-old male patient with a history of difficulty conceiving, a history of orchiectomy due to testicular torsion at 16 years of age, and Chlamydia trachomatis infection at 20 years of age. The physical examination showed normal results, and testicular Doppler ultrasonography presented mild left varicocele. The semen analysis reported oligoasthenozoospermia, positive semen culture on blood agar for Streptococcus spp, and positive chocolate agar for Streptococcus spp. The treatment started with ampicillin-sulbactam administration for 14 days and a check-up after three months with a new semen analysis which showed an improved concentration and progressive sperm motility. Finally, the couple achieved a successful pregnancy. Bacterial colonization of semen contributes to seminal quality alterations; therefore, determining bacteria's presence in infertile couples could help improve seminal parameters and achieve a successful pregnancy.

6.
ACS Omega ; 7(14): 12278-12287, 2022 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-35449951

RESUMO

Over the past years, disposable masks have been produced in unprecedented amounts due to the COVID-19 pandemic. Their increased use imposes significant strain on current waste management practices including landfilling and incineration. This results in large volumes of discarded masks entering the environment as pollutants, and alternative methods of waste management are required to mitigate the negative effects of mask pollution. While current recycling methods can supplement conventional waste management, the necessary processes result in a product with downgraded material properties and a loss of value. This work introduces a simple method to upcycle mask waste into multifunctional carbon fibers through simple steps of thermal stabilization and pyrolysis. The pre-existed fibrous structure of polypropylene masks can be directly converted into carbonaceous structures with high degrees of carbon yield, that are inherently sulfur-doped, and porous in nature. The mask-derived carbon product demonstrates potential use in multiple applications such as for Joule heating, oil adsorption, and the removal of organic pollutants from aqueous environments. We believe that this process can provide a useful alternative to conventional waste management by converting mask waste generated during the COVID-19 pandemic into a product with enhanced value.

7.
Andrology ; 10(5): 844-851, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35460544

RESUMO

AIM: To describe the association between partial thrombosis of the corpus cavernosum, partial priapism, and hard flaccid syndrome. METHODS: A scoping review was performed according to the recommendations of the Joanna Briggs Institute. Moreover, we performed a search strategy using the MEDLINE, EMBASE, and CENTRAL databases. We included the available information, evaluating the conditions of partial thrombosis of the corpus cavernosum, partial priapism, and hard flaccid syndrome, and their molecular and physiological mechanisms and clinical presentation. RESULTS: We identified 207 articles and chose eight studies published between 2001 and 2021. The total number of patients was 34, and their mean age was 28.2 years. Moreover, in 84% of the studies, the pathophysiology of the events was related to microtrauma or prolonged perineal compression. Additionally, 94.2% of the patients had some degree of erectile dysfunction. In addition, out of all patients, 94% underwent magnetic resonance imaging (MRI). However, patients with hard flaccid syndrome did not show relevant findings in these studies. Conversely, MRI showed asymmetry in the proximal corpora cavernosa, thrombosed corpus cavernosum segments, and mainly cavernous fibrous septum in patients with partial cavernous thrombosis and partial priapism. CONCLUSION: Partial thrombosis of the corpus cavernosum, partial priapism, and hard flaccid syndrome occurred more frequently in young patients, possibly related to microtraumas that generate cavernous fibrosis and trigger alterations in the erection of the distal portion of the penis. Additionally, they cause proximal hardening of the pelvis, perineal pain, painful ejaculations, and cavernous asymmetry. Moreover, the imaging characteristics are similar in patients with partial priapism and partial cavernous thrombosis.


Assuntos
Priapismo , Trombose , Adulto , Humanos , Imageamento por Ressonância Magnética/efeitos adversos , Masculino , Dor Pélvica/complicações , Pênis , Priapismo/etiologia , Trombose/complicações
8.
Int J Surg Case Rep ; 83: 105998, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34052715

RESUMO

INTRODUCTION AND IMPORTANCE: Low-Grade Appendiceal Mucinous Neoplasms (LAMN) are noninvasive epithelial tumors of the appendix. Symptomatology is unspecific and can simulate appendicitis. The multidisciplinary approach for the correct diagnosis and management of this kind of tumor is important, as the prognosis depends on it. PRESENTATION OF THE CASE: A 70-years-old man with an appendiceal picture is presented. McBurney and Blumberg's signs were found and the Echography has reported an acute appendicitis. He underwent laparoscopic surgery, founding a Tumor in the Cecum of 10 × 5 cm. We decided to perform an appendectomy with a total cecectomy. The pathological diagnosis was a LAMN. Ten months later, a Computed Tomography (CT) Scan control was performed reporting no evidence of Tumoral activity or Distance Metastasis, neither pseudomyxoma peritonei (PMP) evidence. DISCUSSION: LAMN has been a very controversial tumor. The definitive management is appendectomy. There are controversies about the laparoscopic and open approach, and when there are positive margins. The stage was a pTis (LAMN) pNx according to the 8th edition of the American Joint Committee on Cancer (AJCC). The prognosis depends on the tumoral stage and the presence of PMP. In our case, we have performed a CT scan follow up and there was no Tumoral activity or Distance Metastasis, neither PMP evidence. CONCLUSION: LAMN is a very interesting and rare tumor. The diagnosis of this case was a real challenge. Our management was simple due to the tumoral stage. Pathology played a very important role in treatment and prognosis.

9.
Rev. cuba. obstet. ginecol ; 45(2): e290, abr.-jun. 2019. tab
Artigo em Espanhol | LILACS, CUMED | ID: biblio-1093644

RESUMO

Los suplementos dietarios tales como vitaminas, minerales y antioxidantes mejoran la ingesta de nutrientes. Recientemente se ha descrito que, especialmente aquellos que contienen altas propiedades antioxidantes también mejoran la capacidad fértil. Se presenta el caso de un voluntario de 37 años con posible infertilidad masculina y se desea determinar el efecto del consumo de antioxidantes sobre la calidad seminal. Se realizó evaluación de los parámetros seminales convencionales y funcionales antes y después del uso del suplemento dietario Male Fertility. Se observó que el uso del suplemento dietario incrementó la concentración espermática, el potencial de membrana mitocondrial alto y la capacidad antioxidante del semen; además disminuyó la producción de 1as reactivas de oxígeno, la lipoperoxidación y la fragmentación de la cromática espermática. El suplemento dietario Male Fertility contiene altas concentraciones de vitamina A, C, E, B2, B3, B12, folato, zinc, selenio, acetil L-carnitina, coenzima Q10, L-metionina y licopeno. Se ha descrito que la ingesta de cada uno de estos compuestos tiene efectos positivos sobre la calidad seminal. El reporte de este caso permitió observar que el uso de suplementos dietarios ricos en vitaminas y antioxidantes puede mejorar la calidad seminal a través de la disminución del efecto adverso de las especies reactivas del oxígeno y por el incremento de las moléculas antioxidantes en el plasma seminal(AU)


Dietary supplements such as vitamins, minerals and antioxidants improve nutrient intake. Recently it has been described that, especially those containing high antioxidant properties also improve fertility. We report here the case of a 37-year-old volunteer with possible male infertility and we want to determine the effect of antioxidant consumption on semen quality. Evaluation of the conventional and functional seminal parameters was performed before and after the use of the Male Fertility dietary supplement. The use of this supplement was observed to increased the sperm concentration, the mitochondrial membrane potential and the antioxidant capacity of the semen. In addition, the production of oxygen reactants, lipoperoxidation and fragmentation of the spermatic chromatin decreased. The dietary supplement Male Fertility contains high concentrations of vitamin A, C, E, B2, B3, B12, folate, zinc, selenium, acetyl L-carnitine, coenzyme Q10, L-methionine and lycopene. The ingestion of each of these compounds has been described to have positive effects on seminal quality. The report of this case allowed to observe that the use of dietary supplements rich in vitamins and antioxidants can improve the seminal quality through the decrease of the adverse effect of the reactive oxygen species and by the increase of the antioxidant molecules in the seminal plasma(AU)


Assuntos
Humanos , Masculino , Adulto , Análise do Sêmen/métodos , Infertilidade Masculina/terapia , Antioxidantes/uso terapêutico
10.
Urologia ; 84(3): 148-152, 2017 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-28574143

RESUMO

OBJECTIVES: The aim of this study was to evaluate the safety and efficacy of the artificial urinary sphincter ZSI 375 device in male patients with stress urinary incontinence (SUI) at 10 centres. METHODS: This was a retrospective, nonrandomised, multicentre study. From January 2012 to December 2014, and follow-up to February 2016, men with SUI were treated with the ZSI 375 device. The primary outcome was continence. The secondary outcome was complications rate. RESULTS: A total of 147 patients with moderate-to-severe stress incontinence and mean age of 70.67 (26-85) years underwent implantation of the ZSI 375 device at 10 centres.The most common indication for placement was incontinence after radical prostatectomy (121 patients: 82.31%). The ZSI 375 device was considered successful in 86.40% of cases after 12 months follow-up, 83.52% after 24 months follow-up and 78.26% after 36 months follow-up. The infection rate was 6.12%, urethral erosion was 12.92% and mechanical failure was limited to 3.40% leading to ZSI 375 improvement. CONCLUSIONS: This study confirmed safety and efficacy of ZSI 375 device to treat moderate-to-severe SUI in men.


Assuntos
Incontinência Urinária por Estresse/cirurgia , Esfíncter Urinário Artificial , Adulto , Idoso , Idoso de 80 Anos ou mais , Humanos , Masculino , Pessoa de Meia-Idade , Desenho de Prótese , Estudos Retrospectivos , Resultado do Tratamento
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