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1.
Proc Natl Acad Sci U S A ; 121(31): e2320372121, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39042691

RESUMO

Cells exist in different phenotypes and can transition between them. A phenotype may be characterized by many different aspects. Here, we focus on the example of whether the cell is adhered or suspended and choose particular parameters related to the structure and mechanics of the actin cortex. The cortex is essential to cell mechanics, morphology, and function, such as for adhesion, migration, and division of animal cells. To predict and control cellular functions and prevent malfunctioning, it is necessary to understand the actin cortex. The structure of the cortex governs cell mechanics; however, the relationship between the architecture and mechanics of the cortex is not yet well enough understood to be able to predict one from the other. Therefore, we quantitatively measured structural and mechanical cortex parameters, including cortical thickness, cortex mesh size, actin bundling, and cortex stiffness. These measurements required developing a combination of measurement techniques in scanning electron, expansion, confocal, and atomic force microscopy. We found that the structure and mechanics of the cortex of cells in interphase are different depending on whether the cell is suspended or adhered. We deduced general correlations between structural and mechanical properties and show how these findings can be explained within the framework of semiflexible polymer network theory. We tested the model predictions by perturbing the properties of the actin within the cortex using compounds. Our work provides an important step toward predictions of cell mechanics from cortical structures and suggests how cortex remodeling between different phenotypes impacts the mechanical properties of cells.


Assuntos
Actinas , Adesão Celular , Adesão Celular/fisiologia , Actinas/metabolismo , Animais , Microscopia de Força Atômica/métodos , Fenômenos Biomecânicos , Modelos Biológicos
2.
Public Health ; 233: 157-163, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38901300

RESUMO

OBJECTIVES: This study aimed to provide epidemiological information on drug-facilitated sexual assault in Spanish youth partying, with a focus on prevalence rates and associated sociodemographic factors. STUDY DESIGN: Cross-sectional study. METHODS: Quota sampling was used to recruit 1601 young people aged 18-35 years in Spain from a digital panel. A validated questionnaire on drug-facilitated sexual assault was used to assess five types of lifetime victimisation experiences while partying. Chi-square and the exact Fisher tests were used to describe the prevalence of victimisation, drug use patterns, and perpetrator profiles. Generalised ordered logistic regression was used to explore factors associated with victimisation, analysed by gender. RESULTS: Half of young women and one-quarter of young men had experienced drug-facilitated sexual assault in their lifetime. Female victimisation due to touching and kissing was notably high, whereas men comprised almost half of the victims of more invasive DFSA experiences involving masturbation, penetration, and oral sex. Opportunism prevailed as the assault tactic, consisting of taking advantage of the victims' incapacity derived from voluntary alcohol use. Among women, risk of victimisation was associated with a lower education level, foreign-born status, and being non-heterosexual. Male victimisation risk was highest among non-heterosexual men. CONCLUSIONS: Drug-facilitated sexual violence in youth nightlife contexts is a serious public health issue in Spain, which requires urgent action. Most assaults involve taking advantage of victims who are incapacitated by the effects of voluntary alcohol consumption. This sexual violence primarily affects women with lower educational levels or those who are foreign-born and non-heterosexual men and women.


Assuntos
Vítimas de Crime , Delitos Sexuais , Humanos , Espanha/epidemiologia , Masculino , Feminino , Adolescente , Estudos Transversais , Adulto Jovem , Adulto , Delitos Sexuais/estatística & dados numéricos , Vítimas de Crime/estatística & dados numéricos , Vítimas de Crime/psicologia , Inquéritos e Questionários , Prevalência , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Fatores de Risco
3.
J Appl Microbiol ; 126(5): 1426-1437, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30762925

RESUMO

AIMS: The aim of this study was to find new eukaryotic sources of the l-asparaginase (l-ASNase), since the prokaryotic sources of the enzyme are well-reported as causing allergic hypersensitivity reactions in a significant number of patients. This report describes screening for l-ASNase production by filamentous fungi isolated from the Brazilian Caatinga, and the optimization of fermentation parameters to increase fungal growth and improve yield in the production of l-ASNase. METHODS AND RESULTS: Thirty-two filamentous fungi were investigated in this study. When Aspergillus terreus strain S-18 was cultured in a proline-enriched medium, intracellular l-ASNase was expressed in concurrence with reduced l-glutaminase (l-GLUase) and protease activities. Fermentation conditions were then optimized in a 5-l bioreactor system to produce a maximum volumetric yield of 108 U total of l-ASNase activity. CONCLUSIONS: The work reported here represents the first attempt to produce l-ASNase by filamentous fungi isolated from Brazil and offers a promising alternative eukaryotic source for l-ASNase production. SIGNIFICANCE AND IMPACT OF THE STUDY: In order to minimize the side effects caused by bacterial l-ASNase, the search of eukaryotic micro-organism for l-ASNase was carried out in fungi. This study demonstrates the diversity of filamentous fungi isolated from the Brazilian Caatinga Biome and the importance of knowledge of the microbial metabolism to obtain high concentrations of biotechnological products.


Assuntos
Asparaginase , Aspergillus , Reatores Biológicos/microbiologia , Asparaginase/análise , Asparaginase/metabolismo , Aspergillus/química , Aspergillus/enzimologia , Aspergillus/metabolismo , Brasil , Microbiologia Ambiental , Fermentação , Florestas , Microbiota
4.
Prep Biochem Biotechnol ; 49(1): 95-104, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30488788

RESUMO

L-Asparaginase amidohydrolase (EC 3.5.1.1) has received significant attention owing to its clinical use in acute lymphoblastic leukemia treatment and non-clinical applications in the food industry to reduce acrylamide (toxic compound) formation during the frying of starchy foods. In this study, a sequential optimization strategy was used to determine the best culture conditions for L-asparaginase production from filamentous fungus Aspergillus terreus CCT 7693 by submerged fermentation. The cultural conditions were studied using a 3-level, central composite design of response surface methodology, and biomass and enzyme production were optimized separately. The highest amount of biomass (22.0 g·L-1) was obtained with modified Czapek-Dox medium containing glucose (14 g·L-1), L-proline (10 g·L-1), and ammonium nitrate (2 g·L-1) fermented at 37.2 °C and pH 8.56; for maximum enzyme production (13.50 U·g-1), the best condition was modified Czapek-Dox medium containing glucose (2 g·L-1), L-proline (10 g·L-1), and inoculum concentration of 4.8 × 108 espore·mL-1 adjusted to pH 9.49 at 34.6 °C. The L-asparaginase production profile was studied in a 7 L bench-scale bioreactor and a final specific activity of 13.81 U·g-1 was achieved, which represents an increase of 200% in relation to the initial non-optimized conditions.


Assuntos
Antineoplásicos/metabolismo , Asparaginase/biossíntese , Aspergillus/metabolismo , Técnicas de Cultura de Células , Fermentação , Biomassa , Reatores Biológicos , Meios de Cultura , Glucose/metabolismo , Concentração de Íons de Hidrogênio , Cinética , Nitratos/metabolismo , Prolina/metabolismo , Temperatura
5.
Ann Oncol ; 24(8): 2043-7, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23609186

RESUMO

BACKGROUND: The aim of the present study was to demonstrate that radical hysterectomy (RH) leads to improved survival outcomes in FIGO stage IB2-IIB cervical cancer when compared with standard brachytherapy (BCT) after identical external beam chemoradiation (EBRT-CT). PATIENTS AND METHODS: EBRT-CT treatment consisted of six courses of cisplatin at 40 mg/m² and gemcitabine at 125 mg/m² per week concurrent with 50.4 Gy of radiation. In the BCT arm, EBRT-CT was followed by BCT to reach a point A dose of 85 Gy, whereas in the experimental arm, a type III RH with bilateral pelvic lymph node dissection and para-aortic lymph node sampling (RH) was carried out within 4-6 weeks after EBRT-CT. RESULTS: Between May 2004 and June 2009, 211 patients were enrolled (BCT, 100 and RH, 111). At a median follow-up time of 36 months (3-80), progression-free survival (PFS) and overall survival (OS) rates were similar in both the arms. PFS rates were 74.8% and 71.7% in the BCT and RH arms [HR 0.6516 (95% confidence interval (CI) 0.3504-1.2116)], P = 0.186. OS rates were 76.3% in the BCT versus 74.5% in the surgical arm [HR 0.6981 (95% CI 0.3106-1.3439)], P = 0.236. No differences were observed in the pattern of local and systemic failures. CONCLUSIONS: This study failed to demonstrate that RH after EBRT-CT is superior to standard BCT.


Assuntos
Braquiterapia , Cisplatino/uso terapêutico , Desoxicitidina/análogos & derivados , Histerectomia , Neoplasias do Colo do Útero , Adulto , Idoso , Quimiorradioterapia , Desoxicitidina/uso terapêutico , Intervalo Livre de Doença , Feminino , Humanos , Pessoa de Meia-Idade , Radiossensibilizantes/uso terapêutico , Sobrevida , Resultado do Tratamento , Neoplasias do Colo do Útero/tratamento farmacológico , Neoplasias do Colo do Útero/mortalidade , Neoplasias do Colo do Útero/radioterapia , Neoplasias do Colo do Útero/cirurgia , Adulto Jovem , Gencitabina
6.
Langmuir ; 29(47): 14369-79, 2013 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-24205925

RESUMO

PEG stearates are extensively used as emulsifiers in many lipid-based formulations. However, the scheme of the principles of the lipid-surfactant polymer interactions are still poorly understood and need more studies. A new phase diagram of a lecithin/PEG 40 monostearate/water system at 30 °C is reported. First, we have characterized the binary PEG 40 monostearate/water system by the determination of the critical micelle concentration value and the viscous properties. Then, the ternary phase behavior and the influence of phase structure on their macroscopic properties are studied by a combination of different techniques, namely, optical microscopy, small-angle X-ray scattering, differential scanning calorimetry, and rheology. The phase behavior is complex, and some samples evolve even at long times. The single monophasic regions correspond to micellar, swollen lamellar, and lamellar gel phases. The existence of extended areas of phase coexistence (hexagonal, cubic, and lamellar liquid crystalline phases) may be a consequence of the low miscibility of S40P in the lecithin bilayer as well as of the segregation of the phospholipid polydisperse hydrophobic chains. The presence of the PEG 40 monostearate has less effect in the transformation to the cubic phase for lecithin than that found in other systems with simple glycerol-based lipids.


Assuntos
Glycine max/química , Lecitinas/química , Água/química , Micelas , Estrutura Molecular , Tamanho da Partícula , Tensão Superficial , Viscosidade
7.
Forensic Sci Int ; 301: 447-454, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31153676

RESUMO

This work has shown that it is a valid method for determining ketamine, norketamine and amphetamines derivates in hair samples of forensic cases. This method was validated meeting the criteria of sensitivity and accuracy for detecting repeated consumption of ketamine in hair samples of forensic interest, according to the proposed cut-off for ketamine of 0.5 ng/mg. The detection of norketamine allowed discriminating between active uses and external contamination. The assessed method was applied for analyzing 1189 hair samples of judicial interest received in the INTCF along 15 months, obtaining 62 positive in ketamine consumption. This means a 5.2% of positivity. Ketamine consumers present a profile of young age (21-30 years old), polydrug use with consumption of synthetic substances preferably MDMA and, then, amphetamine. As consumer is collective, prone to consume new psychoactive substances, requires special attention due to they show a consumer profile with higher prevalence in MDMA than amphetamine, indicating that ketamine consumers belong to a subgroup with a different profile within the INTCF casuistry. The results of the exercises of the proficiency tests performed satisfactorily in all cases. In conclusion, it is a suitable method also to evaluate the chronic consumption of ketamine, in addition to amphetamines in the same method of analysis.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Cabelo/química , Ketamina/análogos & derivados , Ketamina/análise , Detecção do Abuso de Substâncias/métodos , Adulto , Anestésicos Dissociativos/análise , Humanos , Limite de Detecção , Transtornos Relacionados ao Uso de Substâncias/diagnóstico , Adulto Jovem
8.
Rev Neurol ; 45(6): 338-40, 2007.
Artigo em Espanhol | MEDLINE | ID: mdl-17899515

RESUMO

INTRODUCTION: Extraspinal tumors are a rare cause of lumbar root compression and neuroendocrine origin are one of the least frequent of this group. CASE REPORT: A 70 years-old woman complained of pain in low back and her right leg. Following image studies a tumor at the level of the L2 vertebrae was diagnosed. This was operated on and a neuroendocrine carcinoma was removed. CONCLUSION: The neuroendocrine tumors show a slow grows typically and are located in the gastrointestinal tract and lung. These are very rare in others localizations.


Assuntos
Carcinoma Neuroendócrino , Canal Medular , Neoplasias da Coluna Vertebral , Idoso , Carcinoma Neuroendócrino/diagnóstico , Carcinoma Neuroendócrino/patologia , Carcinoma Neuroendócrino/cirurgia , Feminino , Humanos , Região Lombossacral , Canal Medular/patologia , Canal Medular/cirurgia , Neoplasias da Coluna Vertebral/diagnóstico , Neoplasias da Coluna Vertebral/patologia , Neoplasias da Coluna Vertebral/cirurgia
9.
Colloids Surf B Biointerfaces ; 131: 21-8, 2015 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-25938851

RESUMO

With the increasing interest in natural formulations for drug administration and functional foods, it is desirable a good knowledge of the phase behavior of lecithin/fatty acid formulations. Phase structure and properties of ternary lecithin/fatty acids/water systems are studied at 37°C, making emphasis in regions with relatively low water and fatty acid content. The effect of fatty acid saturation degree on the phase microstructure is studied by comparing a fully saturated (palmitic acid, C16:0), monounsaturated (oleic acid, C18:1), and diunsaturated (linoleic acid, C18:2) fatty acids. Phase determinations are based on a combination of polarized light microscopy and small-angle X-ray scattering measurements. Interestingly, unsaturated (oleic acid and linoleic acid) fatty acid destabilizes the lamellar bilayer. Slight differences are observed between the phase diagrams produced by the unsaturated ones: small lamellar, medium cubic and large hexagonal regions. A narrow isotropic fluid region also appears on the lecithin-fatty acid axis, up to 8wt% water. In contrast, a marked difference in phase microsctructure was observed between unsaturated and saturated systems in which the cubic and isotropic fluid phases are not formed. These differences are, probably, a consequence of the high Krafft point of the C16 saturated chains that imply rather rigid chains. However, unsaturated fatty acids result in more flexible tails. The frequent presence of, at least, one unsaturated chain in phospholipids makes it very likely a better mixing situation than in the case of more rigid chains. This swelling potential favors the formation of reverse hexagonal, cubic, and micellar phases. Both unsaturated fatty acid systems evolve by aging, with a reduction of the extension of reverse hexagonal phase and migration of the cubic phase to lower fatty acid and water contents. The kinetic stability of the systems seems to be controlled by the unsaturation of fatty acids.


Assuntos
Ácidos Graxos/química , Glycine max/química , Lecitinas/química , Bicamadas Lipídicas/química , Ácidos Graxos Insaturados/química , Cinética , Microscopia de Polarização , Espalhamento a Baixo Ângulo , Água/química , Difração de Raios X
11.
J Colloid Interface Sci ; 238(2): 251-258, 2001 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-11374918

RESUMO

The influence of the addition of the cationic surfactant cetylpyridinium chloride (CPyCl) on the structure of the different phases of the ternary surfactant system C(12)E(4)/benzyl alcohol/water in the dilute region has been studied by means of small angle neutron scattering (SANS) and freeze-fracture microscopy (FF-TEM). In the ternary system various different subregions of the L(alpha)-phase were identified as a function of the concentration of the cosurfactant, benzyl alcohol. Addition of small amounts of CPyCl suppresses these different L(alpha)-phases in favor of the one composed of multilamellar vesicles. Addition of somewhat larger amounts (up to 2 mol% relative to the total surfactant concentration) destabilizes the formation of bilayer structures completely and leads to the formation of micellar solutions. This demonstrates that in this surfactant system the incorporation of very small amounts of cationic surfactant has a pronounced and systematic fluence on its phase behavior and its structures. Copyright 2001 Academic Press.

12.
J Colloid Interface Sci ; 227(1): 171-175, 2000 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-10860608

RESUMO

The influence of a small amount of cetylpyridinium chloride on the phase diagram of the diluted C(12)E(4)/benzyl alcohol/water system is studied. The presence of the ionic surfactant results in the stabilization of the vesicles in relation to the open bilayers. The bilayer structures are less sensitive to shear effects than for the system without cationic surfactant. Moreover, the formation of the mixed micelle phase is also favored. The transition from spherical to rod micelles has been detected from viscosity measurements. The micelles located close to the two-phase region (at the lower amount of cationic surfactant) are the largest and most flexible micelles. Copyright 2000 Academic Press.

13.
Arthritis Rheum ; 37(10): 1441-4, 1994 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7945468

RESUMO

OBJECTIVE: To determine whether clonally expanded B cells are present in the early infiltrates of minor labial salivary glands (LSG) of Sjögren's syndrome (SS) patients. METHODS: Available paraffin-embedded LSG biopsies from 14 patients with primary SS were studied. DNA from LSG tissue was amplified by a polymerase chain reaction directed toward rearranged immunoglobulin gene DNA. RESULTS: All LSG specimens showed oligoclonal or monoclonal B cell expansion. In one patient with plasma cell neoplasm, tumor and LSG specimens obtained at the same operation displayed different immunoglobulin gene rearrangements. CONCLUSION: Clonal expansion is characteristic of primary SS, and it is uniformly found in the early LSG infiltrates of patients who do not experience further progression to pseudolymphoma or lymphoma (mean followup 4.1 years after biopsy). This feature, together with the clonal discordance between the LSG and the B cell neoplasm found in one patient, suggests that additional steps are critical for the progression to malignancy.


Assuntos
Linfócitos B/patologia , Glândulas Salivares Menores/patologia , Síndrome de Sjogren/patologia , Adulto , Idoso , Sequência de Bases , Células Clonais/patologia , DNA/genética , Genes de Imunoglobulinas/genética , Humanos , Pessoa de Meia-Idade , Dados de Sequência Molecular , Reação em Cadeia da Polimerase
14.
Br J Rheumatol ; 34(8): 721-3, 1995 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7551654

RESUMO

We investigate whether a heat-shock protein gene (HSP70-2) is involved in determining susceptibility to systemic lupus erythematosus (SLE) in a Spanish population. A HSP70-2 PstI polymorphism was characterized by restriction fragment length polymorphism analysis of polymerase chain reaction-amplified genomic DNA in 90 SLE patients and 117 controls. The PstI site containing allele (B) was significantly increased in SLE patients compared to healthy controls. This was due to a significant increase in the BB homozygous genotype in patients, particularly in those with diffuse proliferative nephritis. Neither allelic nor genotypic differences were detected when compared by the presence or absence of DR3. The HSP70-2 B allele seems tightly linked to the human leucocyte antigen (HLA) haplotypes carrying susceptibility to SLE in our population. An independent role for this gene cannot be confirmed due to its linkage with HLA DR3.


Assuntos
Genes , Proteínas de Choque Térmico HSP70/genética , Lúpus Eritematoso Sistêmico/genética , Polimorfismo Genético , Alelos , Sequência de Bases , Genótipo , Glomerulonefrite/complicações , Antígeno HLA-DR3/análise , Haplótipos , Humanos , Lúpus Eritematoso Sistêmico/complicações , Lúpus Eritematoso Sistêmico/imunologia , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Valores de Referência
15.
J Colloid Interface Sci ; 211(1): 104-109, 1999 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-9929440

RESUMO

The L phase of the ternary CTAB/benzyl alcohol/water system that extends from the water corner to the alcohol corner was studied by the sound velocity method which indicated variations in velocity when the aggregate structure changed from normal micelles in water to reverse micelles in the alcohol corner of the phase diagram. From these results it was concluded that the transition from normal to reverse micelles takes place while passing through two different bicontinuous regions, one of them with alcohol micro domains dispersed in water and the other one as a bicontinuous reverse region with the predominance of the water domains dispersed in alcohol. Copyright 1999 Academic Press.

16.
Ann Oncol ; 14(8): 1278-84, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12881393

RESUMO

BACKGROUND: Our aim was to evaluate the efficacy and safety of neoadjuvant chemotherapy followed by radical hysterectomy and adjuvant radiation concurrent with weekly cisplatin for locally advanced cervical carcinoma. PATIENTS AND METHODS: Forty-three patients staged as IB2-IIIB were treated with three 21-day courses of carboplatin (area under the time-concentration curve 6 mg.min/ml) and paclitaxel at 175 mg/m(2) by 3-h infusion both on day 1 followed by radical type III hysterectomy and adjuvant radiation concurrent with 6-weekly doses of cisplatin at 40 mg/m(2). Response rate, resectability, toxicity and survival were evaluated. RESULTS: From December 2000 to June 2001, 43 patients were recruited. All were evaluated for response and toxicity to neoadjuvant chemotherapy. A total of 129 courses were administered. Clinical responses were seen in 41 patients (95%) [95% confidence interval (CI) 89.2% to 100%] with four (9%) complete and 37 (86%) partial. Forty-one patients underwent surgery (resectability 95%); pathologically complete or near-complete responses were seen in seven (17%) and eight (20%), respectively, positive surgical margins in five (12%), and positive pelvic lymph nodes in eight (20%). Twenty-six patients were scheduled for adjuvant chemoradiation. External radiation was delivered for 42.8 days (range 33-61), with a mean dose of 49.3 Gy (range 46-56), and a median of five cisplatin courses (two to six). The mean dose of brachytherapy was 32 Gy (range 25.5-35.6). Neoadjuvant therapy was well-tolerated with neutropenia grade 3 and 4 in 12% and 3% of the courses, respectively. Toxicity to adjuvant chemoradiation was mainly hematological and gastrointestinal, mostly grades 1/2. A total of 39 patients completed all scheduled treatment. At a median follow-up of 21 months (range 3-26), the projected overall survival in the intention-to-treat analysis was 79% (95% CI 62% to 88%). CONCLUSIONS: The triple modality of neoadjuvant chemotherapy followed by radical hysterectomy and adjuvant radiation concurrent with cisplatin is a highly active treatment for locally advanced cervical carcinoma with acceptable toxicity.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Histerectomia/métodos , Invasividade Neoplásica/patologia , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/terapia , Adulto , Idoso , Carboplatina/administração & dosagem , Quimioterapia Adjuvante , Cisplatino/administração & dosagem , Terapia Combinada , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Terapia Neoadjuvante/métodos , Estadiamento de Neoplasias , Paclitaxel/administração & dosagem , Radioterapia Adjuvante , Medição de Risco , Taxa de Sobrevida , Resultado do Tratamento , Neoplasias do Colo do Útero/mortalidade
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