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1.
J Anat ; 244(2): 260-273, 2024 02.
Article in English | MEDLINE | ID: mdl-37770122

ABSTRACT

Gut morphology frequently reflects the food organisms digest. Gizzards are organs of the gut found in archosaurs and fishes that mechanically reduce food to aid digestion. Gizzards are thought to compensate for edentulism and/or provide an advantage when consuming small, tough food items (e.g., phytoplankton and algae). It is unknown how widespread gizzards are in fishes and how similar these structures are among different lineages. Here, we investigate the distribution of gizzards across bony fishes to (1) survey different fishes for gizzard presence, (2) compare the histological structure of gizzards in three species, (3) estimate how often gizzards have evolved in fishes, and (4) explore whether anatomical and ecological traits like edentulism and microphagy predict gizzard presence. According to our analyses, gizzards are rare across bony fishes, evolving only six times in a broad taxonomic sampling of 51 species, and gizzard presence is not clearly correlated with factors like gut length or dentition. We find that gizzard morphology varies among the lineages where one is present, both macroscopically (presence of a crop) and microscopically (varying tissue types). We conclude that gizzards likely aid in the mechanical reduction of food in fishes that have lost an oral dentition in their evolutionary past; however, the relative scarcity of gizzards suggests they are just one of many possible solutions for processing tough, nutrient-poor food items. Gizzards have long been present in the evolutionary history of fishes, can be found in a wide variety of marine and freshwater clades, and likely have been overlooked in many taxa.


Subject(s)
Fishes , Animals , Gizzard, Avian/anatomy & histology , Anatomy, Comparative , Fishes/anatomy & histology
2.
Adv Sci (Weinh) ; 9(19): e2105497, 2022 Jul.
Article in English | MEDLINE | ID: mdl-35048569

ABSTRACT

Mechanochemistry uses mechanical force to break, form, and manipulate chemical bonds to achieve functional transformations and syntheses. Over the last years, many innovative applications of mechanochemistry have been developed. Specifically for the synthesis and activation of carbon-rich π-conjugated materials, mechanochemistry offers reaction pathways that either are inaccessible with other stimuli, such as light and heat, or improve reaction yields, energy consumption, and substrate scope. Therefore, this review summarizes the recent advances in this research field combining the viewpoints of polymer and trituration mechanochemistry. The highlighted mechanochemical transformations include π-conjugated materials as optical force probes, the force-induced release of small dye molecules, and the mechanochemical synthesis of polyacetylene, carbon allotropes, and other π-conjugated materials.

3.
Mater Sci Eng C Mater Biol Appl ; 93: 305-318, 2018 Dec 01.
Article in English | MEDLINE | ID: mdl-30274063

ABSTRACT

Trituration is a mechanical process (a form of comminution) for reducing the particle size of a substance. In this manuscript, six different Raw Solid Materials (RSM) which are used in Homeopathy after successive grindings are studied before they are turned into homeopathic solutions. The impact of trituration, with the presence of α­lactose monohydrate (milk sugar) seems to be quite great and interesting because of the variety of grain size which largely differentiate the properties of the materials. The grain sizes obtained triturations by hand according to C. Herring's suggestion leads, finally, measurement scale dimensions. The obtained results can be useful information for all the pharmacy industries, as well as for preparing any kind of powder.


Subject(s)
Lactose/chemistry , Materia Medica/chemistry
4.
Biotechnol Prog ; 34(1): 293-298, 2018 01.
Article in English | MEDLINE | ID: mdl-28726331

ABSTRACT

Biological industries commonly rely on bioreactor systems for the large-scale production of cells. Cell aggregation, clumping, and spheroid morphology of certain suspension cells make their large-scale culture challenging. Growing stem cells as spheroids is indispensable to retain their stemness, but large spheroids (>500 µm diameter) suffer from poor oxygen and nutrient diffusion, ultimately resulting in premature cell death in the centers of the spheroids. Despite this, most large-scale bioprocesses do not have an efficient method for dissociating cells into single cells, but rely on costly enzymatic dissociation techniques. Therefore, we tested a proof-of-concept fluid shear-based mechanical dissociator that was designed to dissociate stem cell spheroids and aggregates. Our prototype was able to dissociate cells while retaining high viability and low levels of apoptosis. The dissociator also did not impact long-term cell growth or spheroid formation. Thus, the dissociator introduced here has the potential to replace traditional dissociation methods. © 2017 American Institute of Chemical Engineers Biotechnol. Prog., 34:293-298, 2018.


Subject(s)
Batch Cell Culture Techniques/methods , Cell Aggregation/genetics , Single-Cell Analysis , Spheroids, Cellular/cytology , Apoptosis/genetics , Bioreactors , Cell Proliferation/genetics , Humans , Oxygen/metabolism
5.
Homeopathy ; 106(3): 160-170, 2017 Aug.
Article in English | MEDLINE | ID: mdl-28844289

ABSTRACT

BACKGROUND: A series of different experimental approaches was applied in Zincum metallicum (Zinc met.) samples and lactose controls. Experiments were designed to elucidate the effect of zinc trituration and dynamization on physicochemical properties of homeopathic formulations, using lactose as excipient. METHODS: Zinc met. potencies (Zinc met 1-3c) were triturated and dynamized using lactose as excipient, according to Brazilian Homeopathic Pharmacopoeia. Lactose samples (LAC 1-3c) were also prepared following the same protocol and used as controls. The samples were analyzed structurally by Atomic Absorption Spectroscopy (AAS), X-ray Diffraction (XRD), Transmission Electron Microscopy (TEM) with Energy Dispersive X-ray Spectroscopy (EDX) and Scanning Electron Microscopy (SEM), and thermodynamically by Thermogravimetry (TG) and Differential Scanning Calorimetry (DSC). RESULTS: AAS analysis detected 97.0 % of zinc in the raw material, 0.75 % (Zinc met 1c) and 0.02% (Zinc met 2c). XRD analysis showed that inter-atomic crystalline spacing of lactose was not modified by dynamization. Amorphous and crystalline lactose spheres and particles, respectively, were observed by TEM in all samples, with mean size from 200 to 800 nm. EDX obtained with TEM identified zinc presence throughout the amorphous matter but individualized zinc particles were not observed. SEM images obtained from dynamized samples (LAC 1c and Zinc met 1c) with electron backscattering could not identify zinc metal grains. The dynamization process induced Derivatives of Thermal Gravimetric (DTg) peak modification, which was previously centered near 158°C to lactose, to a range from 140 to 170°C, suggesting the dynamization process modifies the temperature range of water aggregation. Thermal phenomena were analyzed and visualized by Analysis of Variance (ANOVA) and Principal Component Analysis (PCA) statistics. Both indicated that fusion enthalpy of dynamized samples (DynLAC 1-3c; DynZn 1-3c) increased 30.68 J/g in comparison to non-dynamized lactose (LAC; p < 0.05). CONCLUSIONS: Our results suggested no structural changes due to the trituration and dynamization process. However, TG and DSC analyses permit the differentiation of dynamized and non-dynamized groups, suggesting the dynamization process induced a significant increase in the degradation heat. These results call for further calorimetric studies with other homeopathic dilutions and other methodologies, to better understand the dynamics of these systems.


Subject(s)
Differential Thermal Analysis/methods , Homeopathy/methods , Lactose/analysis , Zinc/analysis , Humans , Microscopy, Electron, Transmission/methods , Spectrometry, X-Ray Emission/methods
6.
J Neurosci Methods ; 286: 69-77, 2017 Jul 15.
Article in English | MEDLINE | ID: mdl-28546101

ABSTRACT

BACKGROUND: Primary culture of postnatal central neurons is a widely used methodology for applications such as the investigation of neuronal development, protein trafficking/distribution and cellular signalling. However, successful production and maintenance of such cultures, particularly from postnatal animals, can be challenging. In attempting to surmount these difficulties, several disparate culturing methodologies have been developed. Such methodologies are centred on the identification and optimisation of critical steps and, as such, the protocols and reagents utilised can differ quite markedly from protocol to protocol, often with the suggestion that the use of a (usually expensive) proprietary reagent(s), lengthy substrate preparation and/or cell isolation techniques is/are necessary for successful culture preparation. NEW METHOD: Herein, we present a simple and inexpensive protocol for the preparation of primary hippocampal neurons from postnatal (2-5 day old) mice, which remain viable for experimental use for over one month. RESULTS: Neurons cultured using this method follow well established developmental norms and display typical responses to standard physiological stimuli such as depolarisation and certain pharmacological agents. COMPARISON WITH EXISTING METHODS/CONCLUSION: By using a novel trituration technique, simplified methodology and non-proprietary reagents, we have developed a reliable protocol that enables the cost effective and efficient production of high quality postnatal mouse hippocampal cultures. This method, if required, can also be utilised to prepare neurons both from other regions of the brain as well as from other species such as rat.


Subject(s)
Cell Culture Techniques/methods , Hippocampus/cytology , Neurons/physiology , Animals , Animals, Newborn , Calcium/metabolism , Cell Culture Techniques/instrumentation , Cells, Cultured , Mice , Nerve Tissue Proteins/metabolism , Neuroglia/physiology , Synapsins/metabolism , Time Factors
7.
Homeopatia Méx ; 85(705): 23-29, Nov-Dic. 2016.
Article in Spanish | HomeoIndex Homeopathy | ID: hom-11704

ABSTRACT

En el siglo XIX la asociación de médicos de Alemania vio como una amenaza el avance de la medicina homeopática, por lo que solicitó al físico alemán Christian Andreas Doppler que realizara un estudio de los medicamentos homeopáticos. El resultado fue el ensayo titulado Grande y pequeño, que dice: "los agentes terapéuticos homeopáticos no actúan por su peso específico, sino que actúan por la acción ejercida por la extensión de la superficie". Sin proponérselo, dicho texto dio inició al formulamiento de las abses cinetíficas que explican la naturaleza y la acción de los medicamentos homeopáticos.El doctor Charles J. Hempel recopila este ensayo en su Materia médica y terapéutica y lo vincula con los procesos inventados por el doctor Hahnemann, trituración con azúcar de leeche y sucusión con alcohol, vehículos que impiden la reunión de los átomos por virtud de la afinidad de atracción que pueda excitar su contacto inmediato del uno al otro, despertándole sus propiedades terapéuticas y reactivando las propiedades cuánticas, y cómo las invenciones del doctor Hahnemann (trituración y sucusión) tienen aplicación en este proceso de conversión de sustancia natural a medicamento homeopático, para conseguir este fin. La trituración y la sucusión corresponden en la física cuántica actual a la ionización, que se compone de dos procesos: transducción y transición electrónica.Además, el doctor Hempel se basa en el resultado de este proceso de conversión para sustentar la acción fisiológica de los medicamntos homeopáticos en el organismo.(AU)


In the nineteenth century the association of german doctors saw as a threat the advancement of homeopathic medicine, so he asked the german physicist Christian Andreas Doppler to conduct a study of homeopathic medicines. The result was the essay entitled Big and small, in which he says: " homeopathic therapeutic agents do not act for their specific weight, but act by the action exerted by the extesion of the surface". Without proposing it, with this essay lays the foudations to lay the scientific basis for homeopathic medicines.Dr. Hempel compiles this essay in his Medical and therapeutic matter, and links it with the processes invented by Dr. Hahnemann, trituration with milk sugar and sucussion with alcohol, tht prevent the prevent the reunion of the atoms by virtue of the affinity of attraction that can excite their immediate contact of one to the other, awakening itd therapeutic properties and reactivating the quantum properties an like the inventions of Dr. Hahnemann (trituration and sucussion) have application in this process of conversion of natural substance to homeopathic medicine to achieve this end. The trituration and sucussion correspond in the current quantum physics to th ionization, wich is composed of two processes: transduction and electronic transition.In addition, Dr. Hempel takes the result of this process of conversion, as a basis to support the physiological action of homeopathic medicines in the bod.(AU)


Subject(s)
Homeopathic Remedy , Mechanisms of Action of Homeopathic Remedies , Quantum Theory
8.
Neurogastroenterol Motil ; 28(8): 1268-71, 2016 08.
Article in English | MEDLINE | ID: mdl-26987693

ABSTRACT

Most drug-drug interactions involve overlap or competition in drug metabolic pathways. However, there are medications, typically resins, whose function is to bind injurious substances such as bile acids or potassium within the digestive tract. The objective of this article is to review the functions of the stomach and the kinetics of emptying of different food forms or formulations to make recommendations on timing of medication administration in order to avoid intragastric drug interactions. Based on the profiles and kinetics of emptying of liquid nutrients and homogenized solids, a window of 3 h between administration of a resin drug and another 'target' medication would be expected to allow a median of 80% of medications with particle size <1 mm to empty from the stomach and, hence, avoid potential interaction such as binding of the 'target' medication within the stomach.


Subject(s)
Food , Gastric Emptying/drug effects , Gastrointestinal Agents/administration & dosage , Gastroparesis/drug therapy , Stomach/drug effects , Drug Administration Schedule , Gastrointestinal Agents/therapeutic use , Humans
9.
J Int Oral Health ; 7(7): 111-4, 2015 Jul.
Article in English | MEDLINE | ID: mdl-26229383

ABSTRACT

BACKGROUND: The study was aimed to evaluate the microleakage of Biodentine using two different manipulation methods by dye penetration. MATERIALS AND METHODS: A total of 60 single-rooted human maxillary permanent teeth were cleaned and obturated with gutta-percha using lateral condensation method. Standardized root-end cavities were prepared after apical resection. All teeth were divided randomly into two groups of 30 specimens and were filled with Biodentine by trituration and hand manipulation methods. The samples were coated with varnish and immersed in 1% methylene blue dye for 72 h. Then the teeth were sectioned longitudinally and observed under a stereomicroscope. The depth of dye penetration was measured in millimeters. RESULTS: There was highly statistical significant difference observed between Group I and Group II (P < 0.001) when dye penetration scores were compared. CONCLUSION: More microleakage was seen when Biodentine was manually manipulated as compared to machine trituration.

10.
Dent Traumatol ; 30(3): 240-5, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24020842

ABSTRACT

INTRODUCTION: The aim of this study was to evaluate the effects of three different mixing techniques on surface microhardness, initial setting time, and phase formation of white mineral trioxide aggregate. METHODS: Twenty-one cylindrical glass tubes were selected and divided into three groups of seven in each (n = 7). White mineral trioxide aggregate (WMTA) in groups A, B, and C were mixed by conventional, trituration, and ultrasonic techniques, respectively. Cements were mixed and packed into the glass tubes and incubated at 37°C for 3 days. After incubation, samples were subjected to microhardness evaluation, and four specimens from each group were prepared and observed under a scanning electron microscopy and X-ray diffraction. For setting time assessment, WMTA was mixed in three parts again, and Gilmore needle test was performed until the initial setting time of cement. Data were analyzed by one-way anova and post hoc Tukey's test. RESULTS: Samples mixed by trituration technique significantly showed the highest microhardness (P < 0.001) and the lowest setting time, while the ultrasonically mixed specimens significantly revealed the highest setting time in comparison with other groups (P < 0.001). Samples mixed by trituration technique showed the highest uniformity in the bulk and highest amount of hydrated calcium silicate (CS) phases, while the lowest value was observed in ultrasonically mixed cements, which also showed the highest amount of anhydrated CS phases. CONCLUSION: Trituration and conventional techniques were more suitable mixing methods for mineral trioxide aggregate in comparison with ultrasonic technique. Trituration resulted in better hydration and crystallization, which prevents clustering of powder and reduces voids and setting time of mixed cement.


Subject(s)
Aluminum Compounds , Calcium Compounds , Oxides , Silicates , Drug Combinations , Microscopy, Electron, Scanning , X-Ray Diffraction
11.
Acta amaz ; 42(1): 11-18, mar. 2012. ilus, graf
Article in Portuguese | LILACS, VETINDEX | ID: lil-607970

ABSTRACT

Os indicadores convencionais de fertilidade de solo, mais comumente utilizados, enfatizam o balanço ácido-base e o conteúdo de elementos químicos, mas não consideram adequadamente as propriedades biológicas do solo, responsáveis por grande parte do seu funcionamento. Os indicadores biológicos, ainda pouco difundidos, levam em consideração a atividade microbiana do solo que é mais sensível à dinâmica do solo. Em Marapanim-PA, e utilizando um desenho experimental inteiramente casualizado, com quatro repetições, avaliou-se o comportamento dos indicadores do solo carbono e nitrogênio da biomassa microbiana, fosfatase ácida, matéria orgânica, carbono orgânico e fósforo disponível, em um solo com cultivo sequencial de mandioca e milho, preparo com corte-e-trituração da capoeira original. Os fatores corte-e-trituração, fosfato natural e adubação verde foram arranjados nos seguintes tratamentos: capoeira; testemunha; fosfato natural (FN); feijão-de-porco [Canavalia ensiformis (L.) DC] (FP); FN + FP; FN + guandu [Cajanus cajan (L.) Millspaugh]. (G); FN + titônia [Tithonia diversifolia (Hemsley) A. Gray] (T); FP + G; FP + T. Em quatro épocas de amostragens, foram tiradas amostras compostas do solo (0 - 10 cm) de cada parcela para análise dos indicadores. Os indicadores estudados foram influenciados pela época de amostragem do solo. Os indicadores fosfatase ácida, nitrogênio da biomassa microbiana e carbono da biomassa microbiana foram capazes de detectar os efeitos de maior número de tratamentos de recuperação do solo testados, enquanto a matéria orgânica do solo foi o menos capaz. Ao longo do tempo, a resposta dos indicadores variou em função dos fatores estudados.


The more commonly used traditional soil fertility indicators emphasize the acid-basic balance and the content of chemical elements, but do not consider adequately the biologic soil properties, largely responsible for soil functioning. The biologic indicators, not yet sufficiently used, take into consideration the microbial activity that is more sensible to soil dynamics. This study was carried out in Marapanim-PA and using a completely randomized plot design, with four replications, to evaluate the behavior of some indicators such as microbial biomass, acid phosphatase, soil organic matter, organic carbon and available phosphorus - in a soil cultivated with cassava and corn, and in which the secondary vegetation was prepared by slash-and-trituration practice. The slash-and-trituration, rock phosphate and green manure factors were arranged in the following treatments: secondary vegetation; control; rock phosphate (RP); wonderbean Canavalia ensiformis (L.) DC (W); RP + W; RP + pigeonpea Cajanus cajan (L.) Millspaugh (P); RP + tithonia Tithonia diversifolia (Hemsley) A. Gray (T); W + P; W + T. In four season of sampling, soil samples were taken from the 0 - 10 cm layer of each parcel to measure the indicator values. The indicators studied were influenced by the time of soil sampling. The acid phosphatase, microbial biomass nitrogen and microbial biomass carbon soil indicators were capable of detecting the effects of a higher number of soil reclamation treatments, while soil organic matter was the least capable. With the passing of time, the response of the indicators varied according to the factors studied.


Subject(s)
Phosphates , Soil , Amazonian Ecosystem
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