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1.
Biol Lett ; 18(4): 20220078, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35414220

RESUMO

The Hemiptera, with approximately 98 000 species, is one of the largest insect orders. Most species feed by sucking sap from plant tissues and are thus often vectors for economically important phytopathogens. Well known within this group are the large cicadas (Cicadomorpha: Cicadoidea: Cicadidae) because they produce extremely loud airborne sounds. Less well known are their mostly tiny relatives, the leafhoppers, spittlebugs, treehoppers and planthoppers that communicate by silent vibrational signals. While the generation of these signals has been extensively investigated, the mechanisms of their perception are poorly understood. This study provides a complete description and three-dimensional reconstruction of a large and complex array of mechanoreceptors in the first abdominal segments of the Rhododendron leafhopper Graphocephala fennahi (Cicadomorpha: Membracoidea: Cicadellidae). Further, we identify homologous organs in the spittlebug Philaenus spumarius (Cicadomorpha: Cercopoidea: Aphrophoridae) and the planthopper Issus coleoptratus (Fulgoromorpha: Fulgoroidea: Issidae). Such large abdominal sensory arrays have not been found in any other insect orders studied so far. This indicates that these sense organs, together with the signal-producing tymbal organ, constitute a synapomorphy of the Tymbalia (Hemiptera excl. Sternorrhyncha). Our results contribute to the understanding of the evolution from substrate-borne to airborne communication in insects.


Assuntos
Hemípteros , Animais , Órgãos dos Sentidos
2.
Eur J Pharm Sci ; 184: 106407, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-36809814

RESUMO

Crystalline mannitol is commonly used as bulking agent in antibody formulations to provide structure to the lyophilized cake and prevent collapse. Depending on the lyophilization process conditions mannitol can either crystallize as α-, ß-, δ-mannitol, mannitol-hemihydrate, or transition to its amorphous state. While crystalline mannitol helps to create a firmer cake structure this is not true for amorphous mannitol. The hemihydrate is also an undesired physical form as it may reduce the drug product stability by releasing bound water molecules into the cake. Our aim was to simulate lyophilization processes in an X-ray powder diffraction (XRPD) climate chamber. In the climate chamber, the process can be carried out fast with low sample quantities to determine optimal process conditions. Insights on the emergence of desired anhydrous mannitol forms helps to adjust the process parameters in larger scale freeze-dryers. In our study we have identified the critical process steps for our formulations and then varied relevant process parameters, which were the annealing temperature, annealing time and temperature ramp rate of the freeze-drying process. Furthermore, the effect of the presence of antibodies on excipient crystallization was investigated by performing the studies on placebo solutions versus two respective antibody formulations. A comparison of the products obtained in a freeze-dryer and the simulated process in the climate chamber showed good accordance demonstrating the method as suitable tool to identify ideal process conditions on a laboratory scale.


Assuntos
Anticorpos , Manitol , Manitol/química , Composição de Medicamentos/métodos , Difração de Raios X , Liofilização/métodos , Excipientes/química , Varredura Diferencial de Calorimetria
3.
Biodivers Data J ; 10: e77025, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35068979

RESUMO

VIETBIO [Innovative approaches to biodiversity discovery and characterisation in Vietnam] is a bilateral German-Vietnamese research and capacity building project focusing on the development and transfer of new methods and technology towards an integrated biodiversity discovery and monitoring system for Vietnam. Dedicated field training and testing of innovative methodologies were undertaken in Cuc Phuong National Park as part and with support of the project, which led to the new biodiversity data and records made available in this article collection. VIETBIO is a collaboration between the Museum für Naturkunde Berlin - Leibniz Institute for Evolution and Biodiversity Science (MfN), the Botanic Garden and Botanical Museum, Freie Universität Berlin (BGBM) and the Vietnam National Museum of Nature (VNMN), the Institute of Ecology and Biological Resources (IEBR), the Southern Institute of Ecology (SIE), as well as the Institute of Tropical Biology (ITB); all Vietnamese institutions belong to the Vietnam Academy of Science and Technology (VAST). The article collection "VIETBIO" (https://doi.org/10.3897/bdj.coll.63) reports original results of recent biodiversity recording and survey work undertaken in Cuc Phuong National Park, northern Vietnam, under the framework of the VIETBIO project. The collection consist of this "main" cover paper - characterising the study area, the general project approaches and activities, while also giving an extensive overview on previous studies from this area - followed by individual papers for higher taxa as studied during the project. The main purpose is to make primary biodiversity records openly available, including several new and interesting findings for this biodiversity-rich conservation area. All individual data papers with their respective primary records are expected to provide useful baselines for further taxonomic, phylogenetic, ecological and conservation-related studies on the respective taxa and, thus, will be maintained as separate datasets, including separate GUIDs also for further updating.

4.
Eur Biophys J ; 40(3): 305-16, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21161524

RESUMO

Uropathogenic Escherichia coli (UPEC) express various kinds of organelles, so-called pili or fimbriae, that mediate adhesion to host tissue in the urinary tract through specific receptor-adhesin interactions. The biomechanical properties of these pili have been considered important for the ability of bacteria to withstand shear forces from rinsing urine flows. Force-measuring optical tweezers have been used to characterize individual organelles of F1C type expressed by UPEC bacteria with respect to such properties. Qualitatively, the force-versus-elongation response was found to be similar to that of other types of helix-like pili expressed by UPEC, i.e., type 1, P, and S, with force-induced elongation in three regions, one of which represents the important uncoiling mechanism of the helix-like quaternary structure. Quantitatively, the steady-state uncoiling force was assessed as 26.4 ±1.4 pN, which is similar to those of other pili (which range from 21 pN for S(I) to 30 pN for type 1). The corner velocity for dynamic response (1,400 nm/s) was found to be larger than those of the other pili (400-700 nm/s for S and P pili, and 6 nm/s for type 1). The kinetics were found to be faster, with a thermal opening rate of 17 Hz, a few times higher than S and P pili, and three orders of magnitude higher than type 1. These data suggest that F1C pili are, like P and S pili, evolutionarily selected to primarily withstand the conditions expressed in the upper urinary tract.


Assuntos
Aderência Bacteriana/fisiologia , Fímbrias Bacterianas/química , Pinças Ópticas , Escherichia coli Uropatogênica/química , Escherichia coli Uropatogênica/ultraestrutura , Fenômenos Biomecânicos , Proteínas de Fímbrias/análise , Proteínas de Fímbrias/química , Fímbrias Bacterianas/classificação , Cinética , Microscopia de Força Atômica/métodos , Modelos Biológicos , Dobramento de Proteína , Estrutura Secundária de Proteína , Eletricidade Estática , Estresse Mecânico , Infecções Urinárias/microbiologia , Escherichia coli Uropatogênica/fisiologia
5.
Eur J Pharm Biopharm ; 159: 143-150, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33429009

RESUMO

Scale-up and transfer of freeze-drying processes is a crucial challenge in biopharma industry. With the success of small batch processing lines utilizing rack vial holding systems, further detailed knowledge about freeze-drying cycles and their scale-up for vials in a rack is required. Therefore, product temperature (TP) profiles as well as Kv values of vials nested in a Polyetheretherketon (PEEK) rack were compared to those of vials placed in a commonly used stainless steel tray. Additionally, both setups were challenged with varying fill volume and partially versus fully loaded rack. Additionally, a process developed for rack was compared to a tray freeze-drying cycle. Freeze-drying in vials placed in the rack is markedly faster for center vials and more homogeneous compared to vials in bulk tray setting, as indicated by TP and Kv values. Due to the more homogeneous drying the rack is more flexible regarding variation of the fill volume. The key point for the transfer of a freeze-drying cycle from rack to tray is to consider the higher sublimation rates in the rack by adapting chamber pressure or shelf temperature for the tray. Furthermore, transfer from one rack per shelf in a laboratory freeze-dryer to pilot scale with four racks per shelf was successful. Thus, understanding of the process in rack and tray setup was enhanced to ensure efficient scale-up and transfer of freeze-drying processes.


Assuntos
Composição de Medicamentos/métodos , Embalagem de Medicamentos/métodos , Liofilização/métodos , Composição de Medicamentos/instrumentação , Embalagem de Medicamentos/instrumentação , Liofilização/instrumentação , Temperatura
6.
Int J Pharm ; 592: 120025, 2021 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-33137451

RESUMO

Minimization of radiation coming from the chamber wall during lyophilization has the potential to reduce the edge-vial-effect. The edge-vial-effect is a phenomenon in which vials positioned at the shelf edges and corners tend to run warmer compared to center vials. A higher product temperature may result in product collapse in these vials. Consequently, more conservative and time-consuming freeze-drying cycles with lower shelf temperatures and pressures are chosen to ensure a product temperature below the collapse temperature in all vials. The edge-vial-effect is of even higher impact in small batches, where the ratio of corner and edge to center vials is higher compared to large scale manufacturing. The chamber wall is often discussed as the primary source of radiation impacting corner and edge vials. A radiation cage was set at different low temperatures to determine the impact of chamber wall temperatures below 0 °C on product temperature. At the end of primary drying, product temperature of corner vials could be reduced by 6 °C through the radiation cage but primary drying was elongated. Compared to vials in a tray, the chamber wall temperature had less impact on vials nested in a rack system due to a shielding effect of the rack itself. Corner and center vials ran more homogeneous with radiation cage since the edge and corner vials were slowed down. The difference in primary drying time between corner and center vials in the tray could be significantly reduced by 18% by means of 7 h when the radiation cage was controlled at product temperature and combined with a higher shelf temperature. In summary, the radiation cage is a useful tool for a more homogeneous batch with the potential to reduce primary drying time. Nevertheless, the drying difference between corner and center vials could only be reduced and was not completely eliminated.


Assuntos
Dessecação , Temperatura Alta , Transferência de Energia , Liofilização , Tecnologia Farmacêutica , Temperatura
7.
J Pharm Sci ; 110(3): 1219-1226, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33069707

RESUMO

Batch homogeneity during lyophilization is crucial to ensure products with high quality. Known as edge-vial-effect, vials at the corners and edges tend to run warmer than center vials during primary drying. This is associated with risk of collapse or increased costs due to use of more conservative, longer drying conditions resulting in lower product temperature. The edge-vial-effect has been attributed to radiation coming from the chamber wall. We could show that the neighbor vial has a dominant impact on product temperature during lyophilization. Depending on the number of neighbors as well as the distance to a neighbor vial, the neighbor vial exerts a remarkable cooling effect. Energy transfer by gas conduction enables the cooling effect of a neighboring vial over a distance up to 10 mm. This not only leads to prolonged primary drying but also impacts cake appearance. Thus, to avoid trouble during lyophilization you have to watch out for the neighborhood.


Assuntos
Dessecação , Tecnologia Farmacêutica , Transferência de Energia , Liofilização , Temperatura
8.
Clin Pract Cases Emerg Med ; 4(4): 675-676, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33217306

RESUMO

CASE PRESENTATION: A 40-year-old male presented the the emergency department (ED) due to a diffuse body rash after a sexual encounter. Examination revealed a maculopapular rash that included the palms and soles of the feet bilaterally. A rapid plasma reagin was positive, and the patient was treated with 2.4 million units of benzathine benzylpenicillin intramuscularly. DIAGNOSIS: Secondary syphilis can mimic many disease processes but classically presents as a painless macular rash on the palms of the hands and soles of the feet. Diagnosis is based upon clinical examination coupled with serological testing. Emergency department management should include 2.4 million units of benzathine benzylpenicillin intramuscularly and mitigation strategies.

9.
J Nutr ; 139(4): 640-5, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19193814

RESUMO

The objective of this study was to determine whether green tea (GT) inhibits the expression of genes regulating hepatic lipogenesis and intestinal lipid transport in fructose-fed ovariectomized (OX) rats. OX rats were assigned to: 1) a control group (S) fed the AIN-93G diet with corn starch as the major carbohydrate source; 2) another control group (F) fed the same diet but containing fructose at 60% as the major carbohydrate source; 3) a group fed the F diet but containing 0.5% GT; and 4) a group fed the F diet containing 1% GT. At 6 wk, plasma and liver triglyceride (TG) and cholesterol and expression of liver sterol regulatory element-binding protein-1c (SREBP-1c) and selected genes involved in lipogenesis and lipid transport were measured. Fructose elevated plasma TG and cholesterol compared with the S group. GT at 0.5 and 1.0% markedly lowered plasma and liver TG. Fructose increased the expression of SREBP-1c, fatty acid synthase, and stearoyl-CoA desaturase 1 mRNA in the liver, whereas GT decreased the expression of these lipogenic genes. Similarly, fructose increased the abundance of hepatic 3-hydroxy-3-methyl-glutaryl-CoA reductase mRNA, whereas GT significantly decreased its expression. GT did not alter the expression of scavenger receptor class B, type 1, microsomal TG transfer protein, and apobec 1 in the liver and intestine. The results suggest that the lipid-lowering effect of GT is mediated partly by its inhibition of hepatic lipogenesis involving SREBP-1c and its responsive genes without affecting lipoprotein assembly.


Assuntos
Frutose/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Chá/química , Triglicerídeos/metabolismo , Ração Animal , Animais , Glicemia/metabolismo , Cor , Feminino , Tamanho do Órgão/efeitos dos fármacos , Ovariectomia , RNA Mensageiro/genética , Ratos , Ratos Sprague-Dawley , Proteína de Ligação a Elemento Regulador de Esterol 1/genética
10.
J Nutr ; 138(3): 476-81, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18287352

RESUMO

Nostoc commune var. sphaeroides Kützing (N. commune), a blue-green alga, has been used as both a food ingredient and in medicine for centuries. To determine the effect of N. commune on cholesterol metabolism, N. commune lipid extract was incubated at increasing concentrations (25-100 mg/L) with HepG2 cells, a human hepatoma cell line. The addition of N. commune lipid extract markedly reduced mRNA abundance of 3-hydroxy-3-methylglutaryl-CoA reductase (HMGR) and LDL receptor (LDLR) (P < 0.05), with a concomitant decrease in their protein expression (P < 0.001). Reduced HMGR activity by 90% with N. commune lipid extract confirmed the inhibitory role of N. commune in cholesterol synthesis (P < 0.006). To elucidate a molecular mechanism underlying the repression of HMGR and LDLR by N. commune lipid extract, expression of sterol regulatory element binding protein 2 (SREBP-2) was assessed. Whereas mRNA for SREBP-2 remained unchanged, SREBP-2 mature protein was reduced by N. commune (P < 0.009). In addition, N. commune lipid extract also decreased SREBP-1 mature protein by approximately 30% (P < 0.002) and reduced the expression of SREBP-1-responsive genes such as fatty acid synthase and stearoyl CoA desaturase 1 (SCD-1) (P < 0.05). Therefore, our results demonstrate that N. commune lipid extract inhibits the maturation process of both SREBP-1 and -2, resulting in a decrease in expression of genes involved in cholesterol and fatty acid metabolism.


Assuntos
Eucariotos/química , Lipídeos/farmacologia , Neoplasias Hepáticas/metabolismo , Nostoc commune/química , Proteínas de Ligação a Elemento Regulador de Esterol/metabolismo , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Hidroximetilglutaril-CoA Redutases/genética , Hidroximetilglutaril-CoA Redutases/metabolismo , Lipídeos/química , Lipídeos/isolamento & purificação , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores de LDL/genética , Receptores de LDL/metabolismo , Proteínas de Ligação a Elemento Regulador de Esterol/antagonistas & inibidores
11.
Appl Physiol Nutr Metab ; 36(3): 313-22, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21574779

RESUMO

Obese and diabetic humans display decreased plasma high-density lipoprotein cholesterol (HDL-C) concentrations and an increased risk for coronary heart disease. However, investigation on HDL metabolism in obesity with a particular emphasis on hepatic ATP-binding cassette transporter A1 (ABCA1), the primary factor for HDL formation, has not been well studied. Human apolipoprotein B(100) transgenic (hApoB(tg)) and brown adipose tissue deficient (BATless) mice were crossed to generate hApoB(tg)/BATless mice. Male and female hApoB(tg) and hApoB(tg)/BATless mice were maintained on either a regular rodent chow diet or a diet high in fat and cholesterol until 24 weeks of age. The hApoB(tg)/BATless mice that were fed a HF/HC diet became obese, developed hepatic steatosis, and had significantly elevated plasma insulin levels compared with their hApoB(tg) counterparts, but plasma concentrations of total cholesterol, HDL-C, triglycerides, and free fatty acids and lipoprotein distribution between genotypes were not significantly different. Hepatic expression of genes encoding HDL-modifying factors (e.g., scavenger receptor, class B, type I, hepatic lipase, lecithin:cholesterol acyltransferase, and phospholipid transfer protein) was either altered significantly or showed a trend of difference between 2 genotypes of mice. Importantly, hepatic protein levels of ABCA1 were significantly lowered by ∼35% in male obese hApoB(tg)/BATless mice with no difference in mRNA levels compared with hApoB(tg) counterparts. Despite reduced hepatic ABCA1 protein levels, plasma HDL-C concentrations were not altered in male obese hApoB(tg)/BATless mice. The result suggests that hepatic ABCA1 may not be a primary contributing factor for perturbations in HDL metabolism in obesity-induced hyperinsulinemia.


Assuntos
Tecido Adiposo Marrom/metabolismo , Apolipoproteína B-100/metabolismo , Hiperinsulinismo/metabolismo , Lipoproteínas HDL/metabolismo , Obesidade/complicações , Transportador 1 de Cassete de Ligação de ATP , Transportadores de Cassetes de Ligação de ATP/genética , Transportadores de Cassetes de Ligação de ATP/metabolismo , Animais , Apolipoproteína B-100/genética , Feminino , Regulação da Expressão Gênica/fisiologia , Humanos , Hiperinsulinismo/sangue , Hiperinsulinismo/etiologia , Insulina/sangue , Lipídeos/sangue , Lipoproteínas HDL/genética , Fígado/metabolismo , Masculino , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Obesidade/metabolismo
12.
Nutr Res ; 28(2): 83-91, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19083393

RESUMO

We investigated whether lipid extract from a blue-green alga, N commune, modulates proinflammatory gene expression in RAW 264.7 macrophages. The cells were incubated with N commune lipid extract (0-100 microg/mL) and subsequently activated by LPS (100 ng/mL). Quantitative real-time PCR analysis showed that mRNA abundance of proinflammatory mediators, including TNF-alpha, COX-2, IL-1beta, IL-6, and iNOS, was significantly reduced by N commune lipid extract in a dose-dependent manner. Secretion of TNF-alpha and IL-1beta into cell culture medium was also significantly decreased by N commune lipid extract. Thin-layer chromatography-densitometry analysis showed that N commune lipid extract contained approximately 15% of fatty acids. To determine whether the inhibition of proinflammatory mediator production by N commune lipid extract is primarily conferred by fatty acids in the lipid extract, macrophages were incubated with 100 microg/mL of N commune lipid extract or 15 microg/mL of a fatty acid mixture, which was formulated to reflect the fatty acid composition of N commune lipid extract. The fatty acid mixture significantly reduced RNA abundance of TNF-alpha and COX-2, but to a lesser extent than did the N commune lipid extract, suggesting the presence of additional bioactive compounds with an antiinflammatory property in the lipid extract. As NF-kappaB is a major regulator for the proinflammatory gene expression, we measured its DNA-binding activity. DNA-binding activity of NF-kappaB was significantly reduced by N commune lipid extract. In conclusion, our study suggests that N commune lipid extract represses the expression of proinflammatory genes in RAW 264.7 macrophages, at least in part, by inhibiting the activation of NF-kappaB pathway.


Assuntos
Regulação da Expressão Gênica/efeitos dos fármacos , Lipídeos/farmacologia , Macrófagos/imunologia , NF-kappa B/antagonistas & inibidores , Nostoc commune/química , Células Cultivadas , Cromatografia em Camada Fina , Densitometria , Relação Dose-Resposta a Droga , Humanos , Lipopolissacarídeos/farmacologia , NF-kappa B/genética , NF-kappa B/metabolismo , Reação em Cadeia da Polimerase , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
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