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1.
Braz J Med Biol Res ; 56: e12713, 2023.
Article in English | MEDLINE | ID: mdl-37493771

ABSTRACT

Mesenchymal stromal/stem cells stem (MSC) have been widely studied due to their great potential for application in tissue engineering and regenerative and translational medicine. In MSC-based therapy for human diseases, cell proliferation is required to obtain a large and adequate number of cells to ensure therapeutic efficacy. During in vitro culture, cells are under an artificial environment and manipulative stress that can affect genetic stability. Several regulatory agencies have established guidelines to ensure greater safety in cell-based regenerative and translational medicine, but there is no specific definition about the maximum number of passages that ensure the lowest possible risk in MSC-based regenerative medicine. In this context, the aim of this study was to analyze DNA damage and chromosome alterations in adipose-derived mesenchymal stromal cells (ADMSC) until the eleventh passage and to provide additional subsidies to regulatory agencies related to number of passages in these cells. Thus, two methods in genetic toxicology were adopted: comet assay and micronucleus test. The comet assay results showed an increase in DNA damage from the fifth passage onwards. The micronucleus test showed a statistically significant increase of micronucleus from the seventh passage onwards, indicating a possible mutagenic effect associated with the increase in the number of passages. Based on these results, it is important to emphasize the need to assess genetic toxicology and inclusion of new guidelines by regulatory agencies to guarantee the safety of MSC-based therapies for human diseases.


Subject(s)
Mesenchymal Stem Cells , Humans , Tissue Engineering , Genomic Instability , Cell Proliferation , Mutagenesis , Cell Differentiation , Stromal Cells
2.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;56: e12713, 2023. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1447680

ABSTRACT

Mesenchymal stromal/stem cells stem (MSC) have been widely studied due to their great potential for application in tissue engineering and regenerative and translational medicine. In MSC-based therapy for human diseases, cell proliferation is required to obtain a large and adequate number of cells to ensure therapeutic efficacy. During in vitro culture, cells are under an artificial environment and manipulative stress that can affect genetic stability. Several regulatory agencies have established guidelines to ensure greater safety in cell-based regenerative and translational medicine, but there is no specific definition about the maximum number of passages that ensure the lowest possible risk in MSC-based regenerative medicine. In this context, the aim of this study was to analyze DNA damage and chromosome alterations in adipose-derived mesenchymal stromal cells (ADMSC) until the eleventh passage and to provide additional subsidies to regulatory agencies related to number of passages in these cells. Thus, two methods in genetic toxicology were adopted: comet assay and micronucleus test. The comet assay results showed an increase in DNA damage from the fifth passage onwards. The micronucleus test showed a statistically significant increase of micronucleus from the seventh passage onwards, indicating a possible mutagenic effect associated with the increase in the number of passages. Based on these results, it is important to emphasize the need to assess genetic toxicology and inclusion of new guidelines by regulatory agencies to guarantee the safety of MSC-based therapies for human diseases.

3.
Sci Rep ; 11(1): 12512, 2021 06 15.
Article in English | MEDLINE | ID: mdl-34131239

ABSTRACT

Cyclic dominance of competing species is an intensively used working hypothesis to explain biodiversity in certain living systems, where the evolutionary selection principle would dictate a single victor otherwise. Technically the May-Leonard models offer a mathematical framework to describe the mentioned non-transitive interaction of competing species when individual movement is also considered in a spatial system. Emerging rotating spirals composed by the competing species are frequently observed character of the resulting patterns. But how do these spiraling patterns change when we vary the external environment which affects the general vitality of individuals? Motivated by this question we suggest an off-lattice version of the tradition May-Leonard model which allows us to change the actual state of the environment gradually. This can be done by introducing a local carrying capacity parameter which value can be varied gently in an off-lattice environment. Our results support a previous analysis obtained in a more intricate metapopulation model and we show that the well-known rotating spirals become evident in a benign environment when the general density of the population is high. The accompanying time-dependent oscillation of competing species can also be detected where the amplitude and the frequency show a scaling law of the parameter that characterizes the state of the environment. These observations highlight that the assumed non-transitive interaction alone is insufficient condition to maintain biodiversity safely, but the actual state of the environment, which characterizes the general living conditions, also plays a decisive role on the evolution of related systems.

4.
Plant Biol (Stuttg) ; 23(2): 229-240, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33012123

ABSTRACT

Herbivory is one of the major biotic stress factors that affect the establishment of plants. However, the main factors that drive herbivory in seedlings of Amazonian tree species are still not well understood. Here we investigated whether contrasting levels of irradiance influence herbivory according to different herbivory indicators and which leaf traits are most related to interspecific variation in herbivory under contrasting irradiance conditions. We measured the leaf area lost as a result of insect herbivory in five tree species planted in a silvicultural system of secondary forest enrichment according to two indicators, herbivore damage (accumulated since plant germination) and herbivory rate (measured over time), and two irradiance conditions, understorey PPFD 2.6 mol·m-2 ·day-1 ) and gap PPFD 33.1 mol·m-2 ·day-1 . Furthermore, we related the interspecific variation in herbivory to a set of leaf traits: SLA, RWC, sclerophylly, phenolic compound content, tannins, condensed tannins and non-structural carbohydrates. Herbivore damage was significantly affected by light availability and species, with the highest percentage variation observed in the Meliaceae (Carapa guianensis and Swietenia macrophylla). For the herbivory rate, only the interspecific variation was significant, with Bertholletia excelsa having the lowest rates. Chemical characteristics (phenolic compounds and tannins) were most related to herbivory rates, as well as highly influenced by light conditions. Non-structural carbohydrates (starch and sucrose) were also related to the interspecific variation in herbivory. The phenolic compounds and starch, as affected by light quantity, are species dependent. Thus, the selective pressure on herbivores may be driven by species-dependent responses to light conditions.


Subject(s)
Herbivory , Plant Leaves , Trees , Animals , Herbivory/radiation effects , Insecta/physiology , Phenotype , Plant Leaves/anatomy & histology , Plant Leaves/metabolism , Plant Leaves/radiation effects , Sunlight , Trees/anatomy & histology , Trees/radiation effects
5.
Mater Sci Eng C Mater Biol Appl ; 92: 694-702, 2018 Nov 01.
Article in English | MEDLINE | ID: mdl-30184797

ABSTRACT

Succinyl-ß-CD derivatives were obtained by green synthesis with degrees of substitution (DS) 1.3 and 2.9. The spray-drying technique was used to obtain albendazole (ABZ):succinyl-ß-CD inclusion complexes. Phase solubility diagrams indicated that both succinyl-ß-CD derivatives formed 1:1 molar ratio ABZ complexes, but the complex with DS 2.9 has a lower formation constant. The presence of stable inclusion complexes in aqueous solution was confirmed by NMR. For both complexes the aromatic moiety is encapsulated into the host cavity. In the solid-state, 13C and 15N NMR spectral differences between ABZ and ABZ included in spray-dried systems showed that strong structural changes occurred in the systems. At least two different ABZ amorphous species were identified based on DS. ABZ species were stable over more than six months based on spectral data. Finally, the influence of DS in the number and type of the inclusion complexes was elucidated.


Subject(s)
Albendazole/chemistry , Nuclear Magnetic Resonance, Biomolecular , beta-Cyclodextrins/chemistry
6.
J. Venom. Anim. Toxins incl. Trop. Dis. ; 16(3): 462-469, 2010. ilus
Article in English | VETINDEX | ID: vti-4305

ABSTRACT

The damaging effects of neuwiedase, a non-hemorrhagic snake venom metalloproteinase from P-I class, on gastrocnemius muscle are studied herein. Following neuwiedase injection, ultrastructural alterations were detected early showing disarrangement of skeletal muscle fibers (characterized by discontinuity of Z lines), mitochondrial swelling, and disruption of plasma membrane and basal lamina. Degradation of skeletal muscle and the appearance of an amorphous substance, primarily composed of cellular debris, were noted after 24 hours. The presence of neuwiedase at the injection site (detected by immunocytochemistry) revealed highly specific labeling of myofibril components of damaged myocytes. In addition, proteolysis of muscle proteins assayed through myofibrils extracted from gastrocnemius muscle indicated that neuwiedase provoked degradation of myofibrils, especially myosin. These results suggest that skeletal muscle damage, induced by neuwiedase, is probably due to its proteolytic action on myofibrils, which are responsible for the maintenance of the cellular architecture.(AU)


Subject(s)
Animals , Metalloproteins/adverse effects , Bothrops/classification , Muscle, Skeletal/anatomy & histology , Immunohistochemistry
7.
J. venom. anim. toxins incl. trop. dis ; J. venom. anim. toxins incl. trop. dis;16(3): 462-469, 2010. ilus
Article in English | LILACS | ID: lil-557175

ABSTRACT

The damaging effects of neuwiedase, a non-hemorrhagic snake venom metalloproteinase from P-I class, on gastrocnemius muscle are studied herein. Following neuwiedase injection, ultrastructural alterations were detected early showing disarrangement of skeletal muscle fibers (characterized by discontinuity of Z lines), mitochondrial swelling, and disruption of plasma membrane and basal lamina. Degradation of skeletal muscle and the appearance of an amorphous substance, primarily composed of cellular debris, were noted after 24 hours. The presence of neuwiedase at the injection site (detected by immunocytochemistry) revealed highly specific labeling of myofibril components of damaged myocytes. In addition, proteolysis of muscle proteins assayed through myofibrils extracted from gastrocnemius muscle indicated that neuwiedase provoked degradation of myofibrils, especially myosin. These results suggest that skeletal muscle damage, induced by neuwiedase, is probably due to its proteolytic action on myofibrils, which are responsible for the maintenance of the cellular architecture.


Subject(s)
Animals , Rabbits , Bothrops , Metalloproteases/isolation & purification , Muscle, Skeletal/ultrastructure , Viper Venoms , Rabbits
8.
Planta Med ; 67(8): 771-3, 2001 Nov.
Article in English | MEDLINE | ID: mdl-11731928

ABSTRACT

The essential oils of Piper cernuum and Piper regnellii leaves were analyzed by gas chromatography-mass spectrometry (GC-MS) and the results were compared to that obtained by means of a program designed to analyse (13)C-NMR data of complex mixtures. Bicyclogermacrene (21.88 %)/beta-caryophyllene (20.69 %) and myrcene (52.60 %)/linalool (15.89 %) were the major constituents in essential oil from leaves of P. cernuum and P. regnellii, respectively. Both essential oils presented growth inhibitory activities against Staphylococcus aureus and Candida albicans.


Subject(s)
Anti-Infective Agents/pharmacology , Bacteria/drug effects , Fungi/drug effects , Oils, Volatile/pharmacology , Piperaceae/chemistry , Anti-Bacterial Agents , Anti-Infective Agents/analysis , Anti-Infective Agents/chemistry , Anti-Infective Agents/therapeutic use , Gas Chromatography-Mass Spectrometry , Magnetic Resonance Spectroscopy , Microbial Sensitivity Tests , Oils, Volatile/analysis , Oils, Volatile/chemistry , Oils, Volatile/therapeutic use , Plant Leaves/chemistry
9.
Rev Bras Biol ; 58(2): 203-9, 1998 May.
Article in Portuguese | MEDLINE | ID: mdl-9697653

ABSTRACT

The calliphorids synantropics were studied in three different environments--urban, rural and forest area--in metropolitan region of Curitiba, Paraná, Brazil during october and december of 1996 to estimate the abundance, preferences of the adults to baits (fresh fish, bird liver and human faeces) and the synanthropic index for the most abundant species. A total of 3399 calliphorids of 13 different species were sampled: Phaenicia eximia (Wiedemann, 1819), Phaenicia cuprina (Wiedemann, 1818), Phaenicia sericata (Meigen, 1826), Cochliomyia macellaria (Fabricius, 1775), Chrysomya putoria (Wiedemann, 1818), Chrysomya albiceps (Wiedemann, 1819), Chrysomya megacephala (Fabricius, 1794), Hemilucilia segmentaria (Fabricius, 1805), Hemilucilia semidiaphana (Rondani, 1850), Paralucilia xanthogeneiates (Dear, 1850), Paralucilia fulvinota (Bigot, 1877), Sarconesia chlorogaster (Wiedemann, 1930) and Calliphora erytrocephala Meigen, 1826.


Subject(s)
Diptera/physiology , Insect Vectors/physiology , Animals , Birds , Brazil , Climate , Diptera/classification , Ecosystem , Feces , Fishes , Humans , Insect Vectors/classification , Liver , Seasons
10.
Rev Lat Am Enfermagem ; 5(2): 17-22, 1997 Apr.
Article in Portuguese | MEDLINE | ID: mdl-9370752

ABSTRACT

The present study aims at reporting the experience of construction of an interinstitutional relationship: university and health services, pointing out the possibilities and difficulties of the process.


Subject(s)
Health Services , Interprofessional Relations , Universities , Humans
11.
Arq. bras. med. vet. zootec ; Arq. bras. med. vet. zootec. (Online);48(4): 485-9, ago. 1996. tab
Article in Portuguese | LILACS | ID: lil-256986

ABSTRACT

O Trypanosoma evansi é um tripanosoma da secçäo salivaria pertencente ao subgênero Trypanozoon. Ele causa a "surra" no velho mundo e o "mal de caderas" na área subtropical da Argentina e no Pantanal, Brasil. Há similaridades entre as lesöes e patogenia causadas por T. brucei, T. evansi e T. equiperdum, inclusive no consumo de plaquetas na coagulaçäo intravascular disseminada (DIC). O presente estudo mostra os valores de APTT, PT e contagem de plaquetas evidenciando a DIC no primeiro relato de infecçäo natural pelo T. evansi em cäo no Pantanal, Brasil


Subject(s)
Animals , Dogs/parasitology , Disseminated Intravascular Coagulation/veterinary , Trypanosoma
12.
Rev. bras. cancerol ; 41(4): 257-60, out.-dez. 1995. ilus
Article in Portuguese | LILACS | ID: lil-198539

ABSTRACT

Paciente de 52 anos submetida a transplante cardíaco ortotópico em maio de 1991, tendo apresentado como complicaçäo tardia o surgimento de carcinoma epidermóide de amígdala. O diagnóstico inicial foi de neoplasia metastática de sítio primário desconhecido porque o tumor primário somente manifestou-se após 6 meses do surgimento da metástase à distância. A incidência de neoplasia no primeiro ano pós-transplante cardíaco é pouco freqüente, assim como o carcinoma epidermóide de amígdala na populaçäo normal. Näo encontramos relato de caso na literatura entre pacientes submetidos a transplante cardíaco e apresentando carcinoma epidermóide de amígdala.


Subject(s)
Humans , Female , Middle Aged , Carcinoma, Squamous Cell , Heart Transplantation , Postoperative Complications , Tonsillar Neoplasms
15.
Oecologia ; 66(2): 264-270, 1985 May.
Article in English | MEDLINE | ID: mdl-28311599

ABSTRACT

Collections over four years in the habitat of submerged litter show that shrimps are abundant the year round. Mean densities vary from 5-45 animals/m2 of litter habitat. Finegrained density distribution within litter sites is highly clumped, but coarse-grained distribution in any given month between litter sites along the river is grosso-modo random.Density and species distribution are a function of the annual cycles of inundations. Of the five species (of a total of seven in the area) that were found to be breeding in the litter habitat it could be established that reproduction is restricted to the period of rising and highest water levels. Reproduction is low in all species, namely below 20 eggs per egg batch with essentially a single generation per year.Breeding ecology in relation to the litter habitat is briefly discussed.

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