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1.
Cryobiology ; 100: 164-172, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33485899

RESUMO

We aimed to assess the feasibility of passive slow freezing (PSF using Mr. Frosty container, Nalgene) as an alternative to controlled slow rate freezing (CSF using (Freezal™, Air liquide)) for human ovarian tissue (OT) cryopreservation. Validation studies needed were determined after assessing the risk associated (EuroGTP-II ART tool) and were conducted in 66 OT samples from 10 transgender men aged 23.4 ± 5.1 y. Folliculogenesis was assessed in vitro (after 2 h and 2 days of culture) and in vivo (2, 4 and 6 weeks xenotransplantation in Balbc/nude mice) by haematoxilin-eosin staining. Fibrosis was assessed by Masson's trichrome staining. Immunohistochemistry was used to study cell proliferation (PCNA and Ki-67) and apoptosis (caspase-3 and TUNEL). Differences in percentages were estimated using a generalized estimated equations method. After 2 days of in vitro culture, higher odds of primordial follicles (PF) (OR 1.626; 95%CI (1.162-2.266); P = 0.004) and lower odds of growing follicles (GF) (OR 0.616; 95%CI (0.441-0.861); P = 0.004) were associated with the established CSF technique. No statistical differences were found in the mean estimated proportion of proliferating (Ki-67+ or PCNA+) or apoptotic (caspase-3+ or Tunel+) follicles. Two and 6 weeks after xenotransplantation, respectively lower odds of GF (OR 0.419; 95%CI (0.217-0.809); P = 0.010) and secondary follicles (OR 0.135; 95%CI (0.071-0.255); P < 0.001) were associated with CSF. Proportion of fibrosis was similar. This validation study shows a higher follicle activation after 2 days in vitro and after 2 weeks following xenotransplantation in mice using PSF. PSF may be an easy, cost-effective low-risk alternative to CSF for cryopreservation of human OT.


Assuntos
Criopreservação , Vitrificação , Animais , Análise Custo-Benefício , Criopreservação/métodos , Feminino , Congelamento , Camundongos , Camundongos Nus
2.
Anim Reprod Sci ; 207: 119-130, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31208845

RESUMO

Fertility preservation is not only a concern for humans with compromised fertility after cancer treatment. The preservation of genetic material from endangered animal species or animals with important genetic traits will also greatly benefit from the development of alternative fertility preservation strategies. In humans, embryo cryopreservation and mature-oocyte cryopreservation are currently the only approved methods for fertility preservation. Ovarian tissue cryopreservation is specifically indicated for prepubertal girls and women whose cancer treatment cannot be postponed. The cryopreservation of pre-antral follicles (PAFs) is a safer alternative for cancer patients who are at risk of the reintroduction of malignant cells. As PAFs account for the vast majority of follicles in the ovarian cortex, they represent an untapped potential, which could be cultivated for reproduction, preservation, or research purposes. Vitrification is being used more and more as it seems to yield better results compared to slow freezing, although protocols still need to be optimized for each specific cell type and species. Several methods can be used to assess follicle quality, ranging from simple viability stains to more complex xenografting procedures. In vitro development of PAFs to the pre-ovulatory stage has not yet been achieved in humans and larger animals. However, in vitro culture systems for PAFs are under development and are expected to become available in the near future. This review will focus on recent developments in (human) fertility preservation strategies, which are often accomplished by the use of in vitro animal models due to ethical considerations and the scarcity of human research material.


Assuntos
Criopreservação/métodos , Preservação da Fertilidade/métodos , Folículo Ovariano/citologia , Ovário , Vitrificação , Animais , Criopreservação/veterinária , Feminino , Preservação da Fertilidade/veterinária , Humanos
3.
Appetite ; 40(2): 93-100, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12781158

RESUMO

A survey was conducted among 345 randomly selected shoppers in Melbourne, Australia, to identify their perceptions of the healthiness of whole milk, reduced fat milk and soy milk and to investigate demographic influences on health perceptions and types of milk consumption. The survey revealed major differences in shoppers' perceptions of the three types of milk along the themes of bone health, weight control, disease prevention, and, allergy and disease causation. Generally whole milk was perceived more negatively than soy or reduced fat milk. There were few demographic differences in the shoppers' perceptions of the three products. Reported consumption of reduced fat milk was more frequent among women and elderly people, and whole milk consumption was positively related to parenthood. The findings suggest that previous marketing and education campaigns have been effective but the widespread uncertainty and erroneous beliefs about milk products suggest that many consumers have not assimilated new findings about milk products. This represents a challenge for industry and public health practitioners.


Assuntos
Atitude , Gorduras na Dieta , Leite , Adolescente , Adulto , Publicidade , Idoso , Animais , Austrália , Bovinos , Participação da Comunidade , Coleta de Dados , Educação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Nutritivo
4.
Public Health Nutr ; 6(2): 201-8, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12675963

RESUMO

OBJECTIVE: To identify consumer perceptions of whole milk, reduced-fat milk and soy milk, and to investigate demographic influences on perceptions and types of milk consumption. DESIGN AND SETTING: Questionnaires covering nutritional and sensory perceptions of three types of milk. SUBJECTS: Three hundred and sixty-one randomly selected shoppers in Melbourne, Australia. RESULTS: Generally, respondents held positive perceptions about milk. Milk was considered as having good sensory properties, providing a good source of nutrients, and being a convenient and safe product. However, despite these findings, misperceptions and unawareness about the nutrient content of milk were prevalent. Negative perceptions were most common for whole milk and were mostly related to its perceived high fat, cholesterol and energy contents. Soy milk received lower ratings on sensory quality and convenience than dairy milk. There were few sociodemographic differences in consumers' perceptions. Although reduced-fat milk consumption was more frequent among elderly people and type of milk consumption was related to parenthood, no other significant effects of demographic variables were found on the consumption of specific milk types. CONCLUSION: Although positive perceptions were common, negative perceptions and misperceptions appear to be prevalent, presenting a challenge for nutrition education. Sociodemographic factors were not shown to be important predictors of perceptions and type of milk consumption.


Assuntos
Bebidas , Leite , Paladar , Adolescente , Adulto , Idoso , Animais , Bovinos , Participação da Comunidade , Gorduras na Dieta/análise , Análise Fatorial , Feminino , Preferências Alimentares , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Leite/química , Leite/normas , Valor Nutritivo , Glycine max , Inquéritos e Questionários , Vitória
6.
J Genet Psychol ; 149(2): 199-210, 1988 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-3404131

RESUMO

The relationship between quality of attachment in infancy and preschooler's reading interests and skills was explored. At 24 months, 77 children and their mothers were tested using the Strange Situation procedure. In a follow-up study 3 years later, 65 mothers completed a questionnaire about the reading interests and skills of their children. Preschool teachers completed a questionnaire about preparatory reading instruction, and the children's intelligence was measured with the Leiden Diagnostic Test. After 3 years, the securely attached children showed more interest in written material than did the insecurely attached children, regardless of their intelligence and the amount of preparatory reading instruction.


Assuntos
Relações Mãe-Filho , Apego ao Objeto , Leitura , Pré-Escolar , Comportamento Exploratório , Feminino , Humanos , Lactente , Masculino , Meio Social
7.
Vet Med (Praha) ; 31(12): 713-24, 1986 Dec.
Artigo em Tcheco | MEDLINE | ID: mdl-3101267

RESUMO

We studied changes in the parameters of the acid-base balance of the blood in cattle before animal transport to the slaughterhouses, after transport, after stunning and before bleeding. At the same time we studied the occurrence of DFD meat by measuring the pH value of the muscle and by determining the meat color. We found out that the disorder of acid-base balance was less manifest, with respect to the large capacity of the buffer systems of the blood, than the changes caused by glycogenolysis in the muscle.


Assuntos
Equilíbrio Ácido-Base , Bovinos/sangue , Carne , Animais
8.
Vet Med (Praha) ; 30(5): 275-88, 1985 May.
Artigo em Tcheco | MEDLINE | ID: mdl-3927553

RESUMO

In four one-year stages (A, B, C, D) in the summer (L) and winter (Z) feeding seasons, the total protein (CB) of blood plasma was determined in 3207 cows included in three groups: I - the first stage of lactation, II - the second stage of lactation, and III - the 8th to 9.5th month of pregnancy. 1948 cows were examined when given the winter feed rations and 1259 cows on the summer rations. At the same time, the supply of required digestible crude protein (SNL) and energy (starch units) was calculated for the feed rations of different groups of cows. High-pregnant cows (III) had the lower total protein in all the four years and feeding seasons, as compared with the groups of lactating cows. The difference was significant in nine out of ten cases in relation to group I and in eight cases in relation to group II. This is a regular phenomenon, independent of the summer or winter feed ration type and of the seasonal climatic effects of each year. The trend of decreasing crude protein levels with the length of lactation is less conclusive (significant in four out of ten cases); nevertheless, it is still apparent, since none of the three reverse cases was significant. The differences in total protein concentration between cows of different groups are absolute and their causes must be endogenous: they cannot be attributed to differences in the supply of required nutrients. A rise of total protein content was recorded in both feeding seasons at stages C and D in all groups of cows. The higher occurrence of hyperproteinaemia is ascribed to increased proteosynthesis at better utilization of the supplied crude protein. Relative (concentration) hyperproteinaemia was excluded. The effect of the summer or winter type of feed rations on total protein concentration was insignificant when considered for the whole four-year period; at individual stages significantly higher total protein values in the summer feeding season than in the winter feeding season were recorded three times and the reverse case was recorded only once.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal , Proteínas Sanguíneas/análise , Bovinos/sangue , Estro , Animais , Feminino , Lactação , Gravidez , Estações do Ano
9.
Vet Med (Praha) ; 27(9): 513-23, 1982 Sep.
Artigo em Tcheco | MEDLINE | ID: mdl-6815862

RESUMO

In 3337 dairy cows, urine was examined for ketone bodies by help of Bililabstix during the first and second phase of lactation and in the eighth to the ninth and a half month of pregnancy; at the same time needed supply of energetic nutrients in 175 summer and 308 winter feed rations was calculated. Intensity and frequency of ketonuria in lactating cows fed winter rations is significantly higher than in those fed green feeds; it decreases significantly with a phase of lactation and with milk production. On the contrary, cows in late pregnancy have higher intensity and frequency of ketonuria (32.9%) when fed green feeds than when fed winter rations (30.7%). In winter feed rations energy input was significantly lower, percentage of deficient feed rations at a relatively broader caloric-protein ratio was higher than in summer season. The highest deficits of energy and digestible nitrogen compounds were observed in cows in the first phase of lactation. Discussion concerns the causes and mechanisms of different ketonuria in groups of dairy cows in relation to deficit of energetic nutrients, caloric-protein ratio, to the level of glycaemia, non-esterified fatty acids in plasma, triglycerides of plasma and to the state of liver function.


Assuntos
Bovinos/urina , Corpos Cetônicos/urina , Animais , Feminino , Gravidez , Estações do Ano
11.
Vet Med (Praha) ; 22(4): 229-36, 1977 Apr.
Artigo em Tcheco | MEDLINE | ID: mdl-408964

RESUMO

The effect of the competitive relationship between potassium and hydrogen in the excretory mechanism of the kidneys on metabolism was studied in calves. The intraruminal exposure of calves to 5.6 meq potassium chloride (KCl) per kg per day has, in itself, only a slight acidotic effect ascribable to a slight reduction of the excretion of acid by the kidney. The same dose of ammonium chloride (NH4Cl) has a strong acidotic effect combined with a negative influence on weight gain. Both basic types of exposure increase the concentration of inorganic phosphorus and reduce the concentration of chlorine in the blood serum. The addition of 2.8 meq of potassium chloride per kg per day to the basic dose of ammonium chloride increases metabolic acidosis, worsens the health condition (being, at times, hazardeous to life) and leads to weight losses. The same amount of ammonium chloride added to the basic dose of ammonium chloride has a relatively small acidotic action on the blood, evoking only a slight and temporary potassium retention in the serum. The negative action on the weight gains and clinical symptoms are generally weaker than in the other group. The results indicate that the acidotic environment creates in ruminants a very dangerous situation if the organism is excessively exposed to the effect of potassium at the same time.


Assuntos
Equilíbrio Ácido-Base/efeitos dos fármacos , Bovinos/metabolismo , Hidrogênio/farmacologia , Rim/metabolismo , Cloreto de Potássio/farmacologia , Cloreto de Amônio/farmacologia , Animais , Composição Corporal/efeitos dos fármacos , Masculino
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