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1.
J Phys Chem A ; 128(27): 5398-5407, 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38918082

RESUMO

Thermo-oxidation of biomass is an important process that occurs through a variety of reaction pathways depending on the chemical nature of the molecules and reaction conditions. These processes can be modeled using reactive molecular dynamics to study chemical reactions and the evolution of converted molecules over time. The advantage of this approach is that many molecules can be modeled, but it is challenging to use the large amount of data obtained from such a simulation to determine reaction products and pathways. In this study, we developed a tracking approach to identify the reaction pathways of the dominant reaction products from reactive molecular dynamics simulations. We demonstrated the approach for thermo-oxidation reactions of modified model lignin compounds. For two modified lignin structures, we tracked the evolving chemical species to find the most common reaction products. Subsequently, we monitored specific bonds to determine the individual steps in the reaction process. This combined approach of reactive molecular dynamics and tracking enabled us to identify the most likely thermo-oxidation pathways. The methodology can be used to investigate the thermo-oxidative pathways of a wider range of chemical compounds.

2.
An Acad Bras Cienc ; 95(3): e20220973, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37909566

RESUMO

This study presents the first complete mitogenome of the Brazilian Atlantic bushmaster Lachesis with insights into snake evolution. The total length was 17,177 bp, consisting of 13 PCGs, 22 tRNAs, two rRNAs and a duplicate control region (CRs). Almost all genes were encoded by the heavy-strand, except for the ND6 gene and eight tRNAs (tRNA-Gln, Ala, Asn, Cys, Tyr, Ser[TGA anticodon], Glu, Pro). Only ATG, ATA, and ATC were starting codons for protein-coding sequences. Stop codons mainly were TAA, AGA, AGG, and TAG; whereas ND1, ND3, and CYTB terminated with incomplete stop codons. Phylogeny retrieved Lachesis within the Crotalinae as the sister group of Agkistrodon; and the Lachesis+Agkistrodon clade as the sister group of (Sistrurus+Crotalus)+Bothrops. The tree supports Crotalinae, Viperinae, and Azemiopinae in the Viperidae family, being sister taxa of Colubridae+(Elapidae+Psammophiidae). The mean genetic distance across 15 snake families and 57 nucleotide sequences was 0.37. The overall mean value of genetic distance across the Crotalinae was 0.23, with Lachesis muta exhibiting the shortest distance of 0.2 with Agkistrodon piscivorus, Protobothrops dabieshanensis and P. flavoviridis and the greatest 0.25 with Gloydius blomhoffii, Trimeresurus albolabris, S. miliarius, and Deinagkistrodon acutus. The complete Atlantic L. muta mitogenome presented herein is only the third annotated mitogenome from more than 430 described Brazilian snake species.


Assuntos
Crotalinae , Genoma Mitocondrial , Viperidae , Humanos , Animais , Crotalinae/genética , Viperidae/genética , Genoma Mitocondrial/genética , Códon de Terminação , Brasil
3.
Int Braz J Urol ; 49(5): 580-589, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37390124

RESUMO

OBJECTIVE: To report outcomes from the largest multicenter series of penile cancer patients undergoing video endoscopic inguinal lymphadenectomy (VEIL). MATERIALS AND METHODS: Retrospective multicenter analysis. Authors of 21 centers from the Penile Cancer Collaborative Coalition-Latin America (PeC-LA) were included. All centers performed the procedure following the same previously described standardized technique. Inclusion criteria included penile cancer patients with no palpable lymph nodes and intermediate/high-risk disease and those with non-fixed palpable lymph nodes less than 4 cm in diameter. Categorical variables are shown as percentages and frequencies whereas continuous variables as mean and range. RESULTS: From 2006 to 2020, 210 VEIL procedures were performed in 105 patients. Mean age was 58 (45-68) years old. Mean operative time was 90 minutes (60-120). Mean lymph node yield was 10 nodes (6-16). Complication rate was 15.7%, including severe complications in 1.9% of procedures. Lymphatic and skin complications were noted in 8.6 and 4.8% of patients, respectively. Histopathological analysis revealed lymph node involvement in 26.7% of patients with non-palpable nodes. Inguinal recurrence was observed in 2.8% of patients. 10y- overall survival was 74.2% and 10-y cancer specific survival was 84.8%. CSS for pN0, pN1, pN2 and pN3 were 100%, 82.4%, 72.7% and 9.1%, respectively. CONCLUSION: VEIL seems to offer appropriate long term oncological control with minimal morbidity. In the absence of non-invasive stratification measures such as dynamic sentinel node biopsy, VEIL emerged as the alternative for the management of non-bulky lymph nodes in penile cancer.


Assuntos
Neoplasias Penianas , Cirurgia Vídeoassistida , Idoso , Humanos , Masculino , Pessoa de Meia-Idade , Canal Inguinal/cirurgia , Canal Inguinal/patologia , Excisão de Linfonodo/métodos , Linfonodos/patologia , Neoplasias Penianas/cirurgia , Neoplasias Penianas/patologia , Resultado do Tratamento , Cirurgia Vídeoassistida/métodos , Estudos Retrospectivos
4.
Proc Natl Acad Sci U S A ; 116(30): 15106-15115, 2019 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-31270239

RESUMO

Salamanders and lungfishes are the only sarcopterygians (lobe-finned vertebrates) capable of paired appendage regeneration, regardless of the amputation level. Among actinopterygians (ray-finned fishes), regeneration after amputation at the fin endoskeleton has only been demonstrated in polypterid fishes (Cladistia). Whether this ability evolved independently in sarcopterygians and actinopterygians or has a common origin remains unknown. Here we combine fin regeneration assays and comparative RNA-sequencing (RNA-seq) analysis of Polypterus and axolotl blastemas to provide support for a common origin of paired appendage regeneration in Osteichthyes (bony vertebrates). We show that, in addition to polypterids, regeneration after fin endoskeleton amputation occurs in extant representatives of 2 other nonteleost actinopterygians: the American paddlefish (Chondrostei) and the spotted gar (Holostei). Furthermore, we assessed regeneration in 4 teleost species and show that, with the exception of the blue gourami (Anabantidae), 3 species were capable of regenerating fins after endoskeleton amputation: the white convict and the oscar (Cichlidae), and the goldfish (Cyprinidae). Our comparative RNA-seq analysis of regenerating blastemas of axolotl and Polypterus reveals the activation of common genetic pathways and expression profiles, consistent with a shared genetic program of appendage regeneration. Comparison of RNA-seq data from early Polypterus blastema to single-cell RNA-seq data from axolotl limb bud and limb regeneration stages shows that Polypterus and axolotl share a regeneration-specific genetic program. Collectively, our findings support a deep evolutionary origin of paired appendage regeneration in Osteichthyes and provide an evolutionary framework for studies on the genetic basis of appendage regeneration.


Assuntos
Ambystoma mexicanum/genética , Evolução Biológica , Ciclídeos/genética , Cyprinidae/genética , Proteínas de Peixes/genética , Peixes/genética , Regeneração/genética , Ambystoma mexicanum/classificação , Nadadeiras de Animais/fisiologia , Animais , Ciclídeos/classificação , Cyprinidae/classificação , Extremidades/fisiologia , Proteínas de Peixes/classificação , Peixes/classificação , Ontologia Genética , Anotação de Sequência Molecular , Filogenia , Transcriptoma
5.
Mol Phylogenet Evol ; 161: 107177, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33866010

RESUMO

The genus Isoëtes is globally distributed. Within the Neotropics, Isoëtes occurs in various habitats and ecosystems, making it an interesting case study to address phylogenetic and biogeographic questions. We sequenced and assembled plastomes and ribosomal DNA (rDNA) sequences to reconstruct phylogenetic relationships in Isoëtes from tropical regions in the Neotropics. The ploidy level of nine taxa was established to address the potential source of phylogenetic incongruence in the genus. Node ages were estimated using MCMCTree. The ancestral range estimates were conducted in BioGeoBEARS. Plastome-based phylogenies were congruent throughout distinct matrices and partition schemes, exhibiting high support for almost all nodes. Whereas, we found incongruences between the rDNA and plastome datasets. Chromosome counts identified three diploids, five tetraploids and one likely hexaploid among Neotropical species. Plastome-based node age estimates showed that the radiation of the crown Isoëtes group occurred at 20 Ma, with the diversification of the tropical American (TAA) clade taking place in the Pleistocene at 1.7 Ma. Ancestral range estimates showed that the ancestor of the TAA clade may have evolved first in the dry diagonal area in South America before reaching more humid regions. In addition, the colonization of the Brazilian semiarid region occurred three times, while the occupation of the Cerrado and Amazon regions occurred twice and once, respectively. Our study showed a large unobserved diversity within the genus in warm-dry regions in the Neotropics. Plastomes provided sufficient genomic information to establish a robust phylogenetic framework to answer evolutionary questions in Isoëtes from the Neotropics.


Assuntos
Ecossistema , Genomas de Plastídeos/genética , Genômica , Filogenia , Filogeografia , Plastídeos/classificação , Plastídeos/genética , Brasil
6.
Phys Rev Lett ; 127(26): 266102, 2021 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-35029489

RESUMO

The change in bending rigidity with temperature κ(T) for 2D materials is highly debated: theoretical works predict both increase and decrease. Here we present measurements of κ(T), for a 2D material: AB-stacked bilayer graphene. We obtain κ(T) from phonon dispersion curves measured with helium atom scattering in the temperature range 320-400 K. We find that the bending rigidity increases with temperature. Assuming a linear dependence over the measured temperature region we obtain κ(T)=[(1.3±0.1)+(0.006±0.001)T/K] eV by fitting the data. We discuss this result in the context of existing predictions and room temperature measurements.

7.
Phys Rev Lett ; 127(2): 029902, 2021 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-34296934

RESUMO

This corrects the article DOI: 10.1103/PhysRevLett.120.226101.

8.
Arch Toxicol ; 95(7): 2335-2350, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34003340

RESUMO

Radioactive iodine released in nuclear accidents may accumulate in the thyroid and by irradiation enhances the risk of cancer. Radioiodine uptake into the gland can be inhibited by large doses of stable iodine or perchlorate. Nutritional iodine daily intake may impact thyroid physiology, so that radiological doses absorbed by the thyroid as well as thyroid blocking efficacy may differ in Japanese with a very rich iodine diet compared to Caucasians. Based on established biokinetic-dosimetric models for the thyroid, we derived the parameters for Caucasians and Japanese to quantitatively compare the effects of radioiodine exposure and the protective efficacy of thyroid blocking by stable iodine at the officially recommended dosages (100 mg in Germany, 76 mg in Japan) or perchlorate. The maximum transport capacity for iodine uptake into the thyroid is lower in Japanese compared to Caucasians. For the same radioiodine exposure pattern, the radiological equivalent thyroid dose is substantially lower in Japanese in the absence of thyroid blocking treatments. In the case of acute radioiodine exposure, stable iodine is less potent in Japanese (ED50 = 41.6 mg) than in Caucasians (ED50 = 2.7 mg) and confers less thyroid protection at the recommended dosages because of a delayed responsiveness to iodine saturation of the gland (Wolff-Chaikoff effect). Perchlorate (ED50 = 10 mg in Caucasians) at a dose of 1000 mg has roughly the same thyroid blocking effect as 100 mg iodine in Caucasians, whereas it confers a much better protection than 76 mg iodine in Japanese. For prolonged exposures, a single dose of iodine offer substantially lower protection than after acute radioiodine exposure in both groups. Repetitive daily iodine administrations improve efficacy without reaching levels after acute radioiodine exposure and achieve only slightly better protection in Japanese than in Caucasians. However, in the case of continuous radioiodine exposure, daily doses of 1000 mg perchlorate achieve a high protective efficacy in Caucasians as well as Japanese (> 0.98). In Caucasians, iodine (100 mg) and perchlorate (1000 mg) at the recommended dosages seem alternatives in case of acute radioiodine exposure, whereas perchlorate has a higher protective efficacy in the case of longer lasting radioiodine exposures. In Japanese, considering protective efficacy, preference should be given to perchlorate in acute as well as prolonged radioiodine exposure scenarios.


Assuntos
Iodo , Neoplasias da Glândula Tireoide , Humanos , Radioisótopos do Iodo/efeitos adversos , Japão , Percloratos/toxicidade , Neoplasias da Glândula Tireoide/prevenção & controle
9.
Artif Organs ; 45(5): E113-E122, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33169400

RESUMO

Tubular polymer scaffolds based on tissue engineering techniques have been studied as potential alternatives for vascular regeneration implants. The blood vessels of the cardiovascular system are mainly fibrous, composed of collagen (Col) and elastin (El), and its inner layer consists of endothelial cells. In this work, Col and El were combined with polyurethane (PU), a biocompatible synthetic polymer, and rotary jet spinning, a new and highly productive technique, to produce fibrous scaffolds. The scaffolds produced at 18 000 rpm presented homogeneous, bead-free, and solvent-free fibers. The blend formation between PU-Col-El was identified by chemical composition analysis and enhanced the thermal stability up to 324°C. The hydrophilic nature of the scaffold was revealed by its low contact angle. Cell viability of human umbilical vein endothelial cells with the scaffold was proven for 72 hours. The combined strategy of rotary jet spinning with a polymer blend containing Col and El was verified as an effective and promising alternative to obtain tubular scaffolds for tissue engineering on a large-scale production.


Assuntos
Materiais Biocompatíveis/química , Prótese Vascular , Engenharia Tecidual/métodos , Alicerces Teciduais/química , Colágeno/química , Elastina/química , Células Endoteliais da Veia Umbilical Humana , Humanos , Interações Hidrofóbicas e Hidrofílicas , Teste de Materiais , Poliuretanos/química
10.
Hautarzt ; 72(1): 34-41, 2021 Jan.
Artigo em Alemão | MEDLINE | ID: mdl-32930854

RESUMO

In many medical expert recommendations and guidelines, the use of compression therapy for acute erysipelas is designated as a contraindication. Due to the sometimes massive oedema, compression therapy is nevertheless used in some clinics. This led to the question whether compression therapy for erysipelas of the lower leg actually leads to complications due to the acute infection and thus represents a contraindication. For the period 01 January 2018 to 30 June 2019, the records of 56 inpatients with acute erysipelas of the lower leg who received compression therapy in addition to systemic antibiotic therapy were retrospectively evaluated. The duration of inpatient treatment, the infection parameters determined as part of the ward routine and any complications that occurred were evaluated. While treated as inpatients the blood parameters for infection clearly dropped. Compression therapy was started on admission day in 92.9% of patients and continued until discharge. None of the patients showed an increase in fever or clinical signs of sepsis during the hospital stay. In this retrospective analysis it could be shown for the first time that compression therapy does not cause a clinical worsening or trigger a septic clinical picture in patients with acute erysipelas. Therefore, the authors consider the declaration of acute erysipelas as contraindication for compression therapy as not justified.


Assuntos
Erisipela , Antibacterianos/uso terapêutico , Celulite (Flegmão)/tratamento farmacológico , Celulite (Flegmão)/terapia , Erisipela/tratamento farmacológico , Erisipela/terapia , Humanos , Perna (Membro) , Estudos Retrospectivos
11.
J Environ Manage ; 232: 818-828, 2019 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-30529869

RESUMO

The Brazilian Cerrado is the second largest biome in Latin America, extending over more than 200 million ha and hosts some of the most intensive agricultural activities for grain and beef production in the world. Because of the biodiversity richness and high levels of endemism, Cerrado is considered one of world's hotspot for biodiversity conservation. The objectives of this study are three-fold: to present a comprehensive division of Cerrado into different ecoregions that reflect the environmental heterogeneity within the biome; to analyze the ecoregions in terms of biophysical characteristics, protected areas, environmental liability in riparian permanent protection areas along watercourses, and priorities for biodiversity conservation; and to rank the ecoregions in terms of endangerment for biodiversity conservation and restoration. A previous study that delineated 22 ecoregions using geomorphology, vegetation, soil, geology, and plant diversity maps was revised using topography, vegetation, precipitation, and soil maps. Our new ecoregion map consists of 19 units that are unique in terms of landscape characteristics and has been adjusted to the current official boundary map of Cerrado. Some of the ecoregions consist of only one geomorphological compartment, whereas others are heterogeneous, consisting of up to eight compartments. Ferralsols comprise the dominant soil type in 14 of the ecoregions. The percentage of protected areas within ecoregions ranges from 1.7% to 51.5%. The most endangered ecoregion, where land use change critically threatens habitat integrity, is the Depressão Cárstica do São Francisco (states of Bahia, Minas Gerais, and Piauí), where environmental liability along riparian permanent protection areas amounts to 85.6% of the total area. Our proposed ecoregion map provides a spatial framework for regional and local assessments to improve decision-making processes to reconcile conservation and restoration planning, sustainable agriculture, and provision of ecosystem services. Besides de adjustment of the previous Cerrado's ecoregion map to the official biome boundary (relevant for the implementation of public policies of conservation as those regulated by the Brazilian Forest Code), the new analyses of the ecoregion map represent a substantial improvement in comparison to the ones conducted by the previous study in 2003. In addition, current web resources allow us to make all the information used or derived from this study available to other users. This opens the possibility of additional improvements of our findings by the scientific community or to be used effectively by decision makers.


Assuntos
Ecossistema , Pradaria , Agricultura , Biodiversidade , Brasil , Conservação dos Recursos Naturais
12.
Int Braz J Urol ; 45(4): 856-857, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30735341

RESUMO

INTRODUCTION: Pelvic Organ Prolapse (POP) is a common condition in elderly resulting from the weakening of the organ suspension elements of multifactorial origin. It compromises significantly the quality of life and can affect more than 50% of multiparous women. Stage IV prolapse or complete uterovaginal eversion corresponds to 10% of the cases and the only form of curative treatment is the surgical correction. The aim of this video is to demonstrate our technique of sacrospinous hysteropexy with a low weight transvaginal polypropylene mesh for treatment of this challenge condition, focusing on technical details in order to prevent mesh related complications. Major, but rare complications, include: infection, prolapse recurrence, abscess formation, bladder perforation and urinary fistula. These situations are related mostly to low volume centers. MATERIALS AND METHODS: A 70 years old female with a stage IV POP had obstructive lower urinary tract symptoms. Only after reducing prolapse, it was possible to urinate, but without stress urinary incontinence. No topic estrogen was prescribed before the surgery and she also didn´t take any kind of hormone replacement therapy. Transvaginal ultrasound and the Pap smear screening were done with normal results. Cystoscopy wasn´t employed at anytime of this procedure. Hydrodissection of vaginal wall was followed by longitudinal incision from the level of bladder neck to the cervix. Notice that the ideal dissection should maintain the vaginal thickness, and address the plane of the connective tissue between the bladder and the vagina. Bladder base is then released from the anterior aspect of the cervix in order to create a site to pericervical ring repair and to fix the apex of the Calistar Soft® with polypropylene 3.0 stitches. A blunt dissection extended downwards through the lateral aspect of the levator ani fascia till the identification of the ischial spine and sacrospinous ligaments bilaterally. Two polypropilene 2.0 threads mounted on a specially designed tissue anchor system (TAS) are then fixed into each sacrospinous ligament 1.5 to 2 cm away from the ischial spine and repaired for further prosthesis anchoring. Then, a longitudinal incision is done at the posterior vaginal wall and the recto-vaginal fascia detachment from the posterior aspect of the pericervical ring is identified and corrected with interrupted polypropylene 2.0 stitches to the cervix and to the pericervical aspect of elongated uterosacrus ligaments bilaterally. The Calistar Soft A (anterior) and P (posterior)® prosthesis were fixed at the anterior and posterior aspects of the cervix, respectively, with interrupted polypropylene 3.0 stitches and meshes' arms are fixed to the sacrospinous ligament using the previously implanted TAS. Then, the distal Calistar Soft A® arms were bilaterally fixed into the internal obturator muscles using its fish spine-like multipoint fix device in order to prevent mesh folding. Finally, perineal body repair was done and vaginal wall was closed with individual absorbable interrupted polyglactin 2.0 sutures and a 16 Fr Foley catheter as well as a vaginal pack embedded on neomicin-bacitracin cream were kept overnight. RESULTS: A high satisfaction rate has been computed with synthetic mesh to POP surgery correction. Approximately 10% of cases of mesh exposure may occur, most of them oligosymptomatic and easy handed by excision or with topic estrogen preparations. After 1 year follow-up, our patient is still satisfied without any complain and no relapse. CONCLUSION: We described a successful treatment of stage IV POP in an old female patient. This technique can be used for advanced end stage POP patients, especially those with some contraindication to sacropromontopexy, but who want to keep vaginal length and uterus. Anatomical knowledge, obedience to technical care, and intensive training are the keys for minimizing the risk of complications. Although we had success with this technique, more studies with proper randomization are necessary to compare success and complications of sacrospinous hysteropexy with a low weight transvaginal polypropylene mesh to sacropromontopexy.


Assuntos
Prolapso de Órgão Pélvico/cirurgia , Polipropilenos/uso terapêutico , Telas Cirúrgicas , Útero/cirurgia , Vagina/cirurgia , Idoso , Feminino , Humanos , Sintomas do Trato Urinário Inferior/cirurgia , Resultado do Tratamento , Bexiga Urinária/cirurgia
13.
Phys Rev Lett ; 120(22): 226101, 2018 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-29906168

RESUMO

A chemically stable bilayers of SiO_{2} (2D silica) is a new, wide band gap 2D material. Up till now graphene has been the only 2D material where the bending rigidity has been measured. Here we present inelastic helium atom scattering data from 2D silica on Ru(0001) and extract the first bending rigidity, κ, measurements for a nonmonoatomic 2D material of definable thickness. We find a value of κ=8.8 eV±0.5 eV which is of the same order of magnitude as theoretical values in the literature for freestanding crystalline 2D silica.

14.
Reprod Domest Anim ; 51(2): 195-203, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26817439

RESUMO

To support conservation strategies in wild species, simple but highly reproducible procedures of sperm cryopreservation are required for an application under field conditions. We used epididymal sperm of the domestic cat to optimize a sperm freezing procedure for felid species, particularly questioning the demand for sperm cooling to 4°C. We equilibrated sperm during slow cooling to only 15 or 10°C in a Tes-Tris-fructose extender with final concentrations of 4.7% (v/v) glycerol and 10% (v/v) of the water-soluble fraction of hen's egg yolk (low-density lipoproteins). Subsequently, sperm were frozen over liquid nitrogen. Total and progressive motility (mean ± SD) after thawing was 60.7 ± 8.6% and 53.9 ± 9.6% in samples cooled to 15°C or 61.6 ± 9.5% and 55.3 ± 9.9% in samples cooled to 10°C. Therefore, a one-step addition of glycerol to sperm at room temperature together with the freezing extender, the use of cryovials (loaded with diluted sperm aliquots of 300 µl), an equilibration period of 40 min comprising slow cooling to 15°C at a rate of approximately -0.14 K/min before rapid freezing over liquid nitrogen, yielded satisfying results. Cooling, freezing and thawing rates were exactly characterized as a prerequisite for further optimization and to provide a repeatable protocol to other practitioners.


Assuntos
Gatos/fisiologia , Criopreservação/veterinária , Epididimo/fisiologia , Preservação do Sêmen/veterinária , Espermatozoides/fisiologia , Animais , Temperatura Baixa , Criopreservação/métodos , Masculino , Preservação do Sêmen/métodos
16.
Phys Rev Lett ; 115(2): 025502, 2015 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-26207478

RESUMO

Using molecular dynamics, we simulate the abrasion process of an atomically rough Fe surface with multiple hard abrasive particles. By quantifying the nanoscopic wear depth in a time-resolved fashion, we show that Barwell's macroscopic wear law can be applied at the atomic scale. We find that in this multiasperity contact system, the Bowden-Tabor term, which describes the friction force as a function of the real nanoscopic contact area, can predict the kinetic friction even when wear is involved. From this the Derjaguin-Amontons-Coulomb friction law can be recovered, since we observe a linear dependence of the contact area on the applied load in accordance with Greenwood-Williamson contact mechanics.

17.
J Phys Chem A ; 118(1): 4-12, 2014 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-24328311

RESUMO

Here we present the first two-dimensional images of the virtual source of a supersonic helium expansion. The images were obtained using a free-standing Fresnel zone plate with an outermost zone width of 50 nm as imaging lens and a beam cooled to around 125 K. The nozzle diameter was 10 µm. The virtual source diameter was found to increase with stagnation pressure from 140 ± 30 µm at po = 21 bar up to 270 ± 25 µm at po = 101 bar. The experimental results are compared to a theoretical model based on the solution of the Boltzmann equation by the method of moments. The quantum mechanical cross sections used in the model have been calculated for the Lennard-Jones (LJ) and the Hurly-Moldover (HM) potentials. By using a scaling of the perpendicular temperature that parametrizes the perpendicular velocity distribution based on a continuum expansion approach, the LJ potential shows a good overall agreement with the experiment. However, at higher pressures the data points lie in between the two theoretical curves and the slope of the trend is more similar to the HM curve. Real gas corrections to enthalpy are considered but they affect the results less than the experimental errors.

18.
BJS Open ; 8(4)2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38987232

RESUMO

BACKGROUND: Inguinal lymph node dissection plays an important role in the management of melanoma, penile and vulval cancer. Inguinal lymph node dissection is associated with various intraoperative and postoperative complications with significant heterogeneity in classification and reporting. This lack of standardization challenges efforts to study and report inguinal lymph node dissection outcomes. The aim of this study was to devise a system to standardize the classification and reporting of inguinal lymph node dissection perioperative complications by creating a worldwide collaborative, the complications and adverse events in lymphadenectomy of the inguinal area (CALI) group. METHODS: A modified 3-round Delphi consensus approach surveyed a worldwide group of experts in inguinal lymph node dissection for melanoma, penile and vulval cancer. The group of experts included general surgeons, urologists and oncologists (gynaecological and surgical). The survey assessed expert agreement on inguinal lymph node dissection perioperative complications. Panel interrater agreement and consistency were assessed as the overall percentage agreement and Cronbach's α. RESULTS: Forty-seven experienced consultants were enrolled: 26 (55.3%) urologists, 11 (23.4%) surgical oncologists, 6 (12.8%) general surgeons and 4 (8.5%) gynaecology oncologists. Based on their expertise, 31 (66%), 10 (21.3%) and 22 (46.8%) of the participants treat penile cancer, vulval cancer and melanoma using inguinal lymph node dissection respectively; 89.4% (42 of 47) agreed with the definitions and inclusion as part of the inguinal lymph node dissection intraoperative complication group, while 93.6% (44 of 47) agreed that postoperative complications should be subclassified into five macrocategories. Unanimous agreement (100%, 37 of 37) was achieved with the final standardized classification system for reporting inguinal lymph node dissection complications in melanoma, vulval cancer and penile cancer. CONCLUSION: The complications and adverse events in lymphadenectomy of the inguinal area classification system has been developed as a tool to standardize the assessment and reporting of complications during inguinal lymph node dissection for the treatment of melanoma, vulval and penile cancer.


Assuntos
Consenso , Técnica Delphi , Canal Inguinal , Excisão de Linfonodo , Melanoma , Neoplasias Penianas , Complicações Pós-Operatórias , Neoplasias Vulvares , Humanos , Excisão de Linfonodo/efeitos adversos , Excisão de Linfonodo/métodos , Feminino , Masculino , Neoplasias Penianas/cirurgia , Neoplasias Penianas/patologia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/epidemiologia , Neoplasias Vulvares/cirurgia , Neoplasias Vulvares/patologia , Melanoma/cirurgia , Melanoma/patologia , Canal Inguinal/cirurgia , Inquéritos e Questionários
19.
Oncology ; 85(4): 223-7, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24080991

RESUMO

OBJECTIVE: Bortezomib (Btz) has emerged as a standard of care in the treatment of patients with multiple myeloma (MM), but Btz-induced peripheral neuropathy (PNP) has a particularly negative impact on patients' quality of life. According to a recent study, PNP was significantly less frequent with subcutaneous administration of Btz. Here, we report our experience regarding the efficacy and tolerability of standard combination regimens in MM with subcutaneous Btz. METHODS: 14 consecutive patients with newly diagnosed MM were included in this analysis. Btz was used in different combination regimens (Btz with dexamethasone with/without thalidomide or Btz combined with melphalan and prednisone). Standard criteria were applied to evaluate response and toxicity. RESULTS: Hematological toxicities occurred only at grades 1-2 and included anemia (71%) and thrombocytopenia (21%). Nonhematologic side effects at grades 1-2 were local skin reactions at the subcutaneous injection site, which were self-limited. No notable gastrointestinal toxicity was observed with subcutaneous Btz, and therefore routine use of intravenous hydration and antiemetics was abandoned. Overall response rate for transplant-eligible patients was 86%. CONCLUSIONS: Our results confirm the improved toxicity profile of the subcutaneous administration of Btz in various standard Btz-based combination regimens. In addition, patient management with subcutaneous administration has been markedly ameliorated at our center.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Mieloma Múltiplo/tratamento farmacológico , Adulto , Idoso , Ácidos Borônicos/administração & dosagem , Bortezomib , Dexametasona/administração & dosagem , Feminino , Humanos , Injeções Subcutâneas , Masculino , Melfalan/administração & dosagem , Pessoa de Meia-Idade , Mieloma Múltiplo/patologia , Prednisona/administração & dosagem , Pirazinas/administração & dosagem , Estudos Retrospectivos , Talidomida/administração & dosagem , Resultado do Tratamento
20.
Dermatologie (Heidelb) ; 74(4): 270-281, 2023 Apr.
Artigo em Alemão | MEDLINE | ID: mdl-36754895

RESUMO

Compression therapy has been an essential part of conservative therapy for people with chronic wounds and edema of the lower extremities for hundreds of years. The initiated therapy can be divided into the decongestion phase, maintenance phase, and prevention. The choice of the respective compression materials is based, among other factors, on these phases, the clinical stage and symptoms, the needs of the affected person and their physical abilities. Today, a wide range of different materials and methods are available for compression therapy. Thus, it is increasingly difficult to keep an overview of these treatment options, especially since the nomenclature used by the manufacturers is often inconsistent. Thus, the materials and methods for compression therapy currently available in German-speaking countries and their clinical indications are described in this review article. In addition, a uniform nomenclature is proposed, on the basis of which an appropriate exchange between all those involved in the care of people with compression therapy is guaranteed.


Assuntos
Bandagens Compressivas , Edema , Humanos , Tratamento Conservador , Pressão , Exame Físico
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