Ohjaava opetustyyli – opetushenkilöstön käsityksiä ja kokemuksia

Tutkielman aiheena oli selvittää, millaisia käsityksiä opetushenkilöstöllä on ohjaavasta opetustyylistä: Mitä ohjaavalla opetuksella tavoitellaan, millaisia toimintatapoja opetus sisältää ja millaisia haasteita opetushenkilöstö arjessa kohtaa. Alun teoreettisessa osuudessa kuvataan kolmen ohjaavan opetustyylin mallia: Feuersteinin ohjattu oppimiskokemus (Mediated Learning Experience), ohjaava opetuskeskustelu eli scaffolding ja dynaaminen arviointi. Keskeistä näissä malleissa on, että oppija nähdään tiedon aktiivisena prosessoijana, oppiminen tapahtuu taitavamman ohjauksessa ja tavoitteena oppimisessa on oppijan ajattelutaitojen ja oppimisprosessien kehittyminen. Tutkielma on laadullinen, fenomenografinen, tutkimus. Tutkielman aineisto koostui kahdeksan henkilön haastattelusta Uudenmaan opetusyksiköistä. Heistä viisi oli työssä peruskoulun ala- tai yläluokilla ja kolme ammatillisessa peruskoulutuksessa. Haastateltavat olivat työssä sekä yleis- että erityisopetuksessa. Tulokset osoittivat, että haastateltavat pitivät tärkeänä oppijan aktiivista roolia oppimisessa, itseohjautuvuuden kehittymistä ja positiivista näkemystä itsestä oppijana. Oppijan omaa ajattelua korostettiin, ja sen nähtiin kehittyvän taitavamman henkilön ohjauksessa. Tuloksissa näkyi, että haastateltavien käsitys oli ohjaavan opetustyylin mukainen, mutta ajattelutaitojen tietoista ja käsitteidenkäytön täsmällistä ohjaamista esiintyi haastateltavien puheessa melko vähän. Ajattelutaidot ja ongelmanratkaisutaidot ovat esimerkiksi peruskoulun uuden opetussuunnitelman (2014) yleisiä tavoitteita. Tämän tutkielman perusteella ohjaavan opetustyylin mukaista toimintamallia ja ajattelutapaa voisi kouluttamalla tuoda enemmän opetushenkilöstön tietoisuuteen ja toimintaan. Kyse ei ole pelkästään ajattelutaitojen ohjaamisen opettelusta, vaan myös näkökulman ja opettajan roolin muutoksesta sisällön tarjoajasta oppimisen ohjaamiseen.

Perinnebiotooppi, hoidettu maisema

Tutkimukseni kohteena ovat satakuntalaisen viiden tilallisen motiivit perinnebiotooppiensa hoitoon. Perinnebiotoopit ovat kasvi- ja eläinlajistoltaan monimuotoisimpia luontotyyppejämme ja maisemaltaan arvokasta maaseudun kulttuurimaisemaa. Tutkimusmetodina käytin teemahaastattelua. Haastattelut tehtiin haastateltavien kotona, jonka jälkeen käytiin maastossa heidän hoitokohteissaan. Vuonna 2006 tein Satakunnan perinnemaisemat – Ohjeita ja kokemuksia perinnemaisemien hoidosta Satakunnassa oppaan. Opasta varten haastattelin 12 tilaa, tarkoituksena oli kertoa satakuntalaisten viljelijöiden kokemuksista perinnebiotooppien sekä luonto - ja maisemakohteiden hoidossa sekä selventää perinnemaisemien käsitettä ja uutta ympäristötukijärjestelmää 2007 - 2013. Hoitokokemukset koottiin haastattelemalla viljelijöitä maastossa heidän hoitokohteissaan. Vuonna 2013 kävin samat kohteet lävitse ja haastattelin tilallisia seitsemän vuotta myöhemmin. 12 tilasta valitsen pienemmän otannan viisi tilaa. Näiden viiden tilan isännän tuntemuksia käyn lävitse. Selvitin tutkielmassani mm. millaisia merkityksiä ja arvoja perinnebiotoopilla on tilanpitäjälle. Onko kyse halusta jatkaa sukupolvien tekemää työtä vai jostain muusta. Miten EU:n tukipolitiikka on vaikuttanut perinnebiotooppien hoitoon. Monet haastatelluista tilallisista seurasivat mielenkiinnolla, kuinka entiset umpeutuneet kohteet avartuvat laiduntamisen myötä. Myös kasvien, perhosten ja lintujen runsautta seurattiin tarkasti. Viljelijöiden omat perinnebiotooppialueet ovat heille tärkeitä, niihin liittyy omakohtaisia kokemuksia lapsuuden maisemista tai niiden hoidolla on selkeä luonnonhoidollinen syy. Alueiden hoidosta maksettava tuki toimii kannustimena alueiden säilyttämisessä hoidettuina. Maatalouden tulisi tuoda viljelijälle riittävän toimeentulon, jotta maatilan toiminta olisi jatkuvaa.

Use of simulated intestinal fluids with Caco-2 cells and rat ileum

In most in vitro studies of oral drug permeability, little attempt is made to reproduce the gastrointestinal lumenal environment. The aim of this study was to evaluate the compatibility of simulated intestinal fluid (SIF) solutions with Caco-2 cell monolayers and Ussing chamber-mounted rat ileum under standard permeability experiment protocols. In preliminary experiments, fasted-state simulated intestinal fluid (FaSSIF) and fed-state simulated intestinal fluid (FeSSIF) solutions based on the dissolution medium formulae of Dressman and co-workers (1998) were modified for compatibility with Caco-2 cells to produce FaS-SIF and FeSSIF "transport" solutions for use with in vitro permeability models. For Caco-2 cells exposed to FaSSIF and FESSIF transport solutions, the transepithelial electrical resistance was maintained for over 4 h and mannitol permeability was equivalent to that in control (Hank's Balanced Salt Solution-treated) cell layers. Scanning electron microscopy revealed that microvilli generally maintained a normal distribution, although some shortening of microvilli and occasional small areas of denudation were observed. For rat ileum in the Ussing chambers, the potential difference (PD) collapsed to zero over 120 min when exposed to the FaSSIF transport solution and an even faster collapse of the PD was observed when the FeSSIF transport solution was used. Electron micrographs revealed erosion of the villi tips and substantial denudation of the microvilli after exposure of ileal tissue to FaSSIF and FeSSIF solutions, and permeability to mannitol was increased by almost two-fold. This study indicated that FaSSIF and FeSSIF transport solutions can be used with Caco-2 monolayers to evaluate drug permeability, but rat ileum in Ussing chambers is adversely affected by these solutions. Metoprolol permeability in Caco-2 experiments was reduced by 33% using the FaSSIF and 75% using the FeSSIF compared to permeability measured using HBSS. This illustrates that using physiological solutions can influence permeability measurements.

Structural changes in the epithelium of the small intestine and immune cell infiltration of enteric ganglia following acute mucosal damage and local inflammation

An acute enteritis is commonly followed by intestinal neuromuscular dysfunction, including prolonged hyperexcitability of enteric neurons. Such motility disorders are associated with maintained increases in immune cells adjacent to enteric ganglia and in the mucosa. However, whether the commonly used animal model, trinitrobenzene sulphonate (TNBS)-induced enteritis, causes histological and immune cell changes similar to human enteric neuropathies is not clear. We have made a detailed study of the mucosal damage and repair and immune cell invasion following intralumenal administration of TNBS. Intestines from untreated, sham-operated and TNBS-treated animals were examined at 3 h to 56 days. At 3 h, the mucosal surface was completely ablated, by 6 h an epithelial covering was substantially restored and by 1 day there was full re-epithelialisation. The lumenal epithelium developed from a squamous cell covering to a fully differentiated columnar epithelium with mature villi at about 7 days. Prominent phagocytic activity of enterocytes occurred at 1-7 days. A surge of eosinophils and T lymphocytes associated with the enteric nerve ganglia occurred at 3 h to 3 days. However, elevated immune cell numbers occurred in the lamina propria of the mucosa until 56 days, when eosinophils were still three times normal. We conclude that the disruption of the mucosal surface that causes TNBS-induced ileitis is brief, a little more than 6 h, and causes a transient immune cell surge adjacent to enteric ganglia. This is much briefer than the enteric neuropathy that ensues. Ongoing mucosal inflammatory reaction may contribute to the persistence of enteric neuropathy.

Vascular endothelial growth factor (VEGF) and VEGF-receptor expression in placenta of hyperglycemic pregnant women

Hyperglycemia occurs in a variety of conditions such as overt diabetes, gestational diabetes and mild hyperglycemia, all of which are generally defined based on the oral glucose tolerance test and glucose profiles. Whereas diabetes has received considerable attention in recent decades, few studies have examined the mechanisms of mild hyperglycemia and its associated disturbances. Mild gestational hyperglycemia is associated with macrosomia and a high risk of perinatal mortality. Morphologically, the placenta of these women is characterized by an increase in the number of terminal villi and capillaries, presumably as part of a compensatory mechanism to maintain homeostasis at the maternal-fetal interface. In this study, we analised the expression of VEGF and its receptors VEGFR-1 (Flt-1) and VEGFR-2 (KDR) in placentas from mildly hyperglycemic women. This expression was compared with that of normoglycemic women and women with gestational and overt diabetes. Immunohistochemistry revealed strong staining for VEGF and VEGFR-2 in vascular and trophoblastic cells of mildly hyperglycemic women, whereas the staining for VEGFR-1 was discrete and limited to the trophoblast. The pattern of VEGF and VEGF-receptor reactivity in placentas from women with overt diabetes was similar to that of normoglycemic women. In women with gestational diabetes, strong staining for VEGFR-1 was observed in vascular and trophoblastic cells whereas VEGF and VEGFR-2 were detected only in the trophoblast. The expression of these proteins was confirmed by western blotting, which revealed the presence of an additional band of 75 kDa. In the decidual compartment, only extravillous trophoblast reacted with all antibodies. Morphological analysis revealed collagen deposition around large arteries in all groups with altered glycemia. These findings indicate a placental response to altered glycemia that could have important consequences for the fetus. The change in the placental VEGF/VEGFR expression ratio in mild hyperglycemia may favor angiogenesis in placental tissue and could explain the hypercapillarization of villi seen in this gestational disturbance. (C) 2010 Elsevier Ltd. All rights reserved.

Morphometry and ultra-structure of the intestinal mucosa of broilers fed different additives

This study aimed at evaluating the effect of the use of different growth promoters on the morphometry and ultra-structure of the intestinal mucosa of 42-day-old broilers. A total number of 36 male Cobb broilers was distributed in a randomized experimental design with a 3 x 3 factorial arrangement, with 3 prebiotic and 3 probiotic sources in the feed, summing up 9 treatments, with 4 replicates each. There was a significant interaction (P<0.01) among the studied factor for villi height (VH) in all intestinal segments, and for crypt depth (CD) in the duodenum and the ileum. In the duodenum, higher villi were obtained in the control group, with the combination of B. subtilis and prebiotics, and with the single use of MOS+OA. No VH differences were observed between the control group and those fed prebiotics. In the jejunum, the highest villi were obtained with the use of the bacterial pool, followed by the control group, and by the use of B. subtilis. Higher villi were also obtained in the control group and in the groups fed MOS, when B. subtilis was used in combination with prebiotics, and when the bacterial pool was used individually or in combination with MOS. In the ileum, the highest villi were obtained with the individual use of B. subtilis, and when MOS+OA or MOS were individually used or in combination with the bacterial pool. As to duodenal CID, deeper crypts were observed in the control group and in those fed B. subtilis or MOS+OA. In the ileum, deeper crypts were also found in the control group and those fed B. subtilis. Deeper crypts were also found when the bacterial pool was individually used or in combination with MOS+OA, and with the individual use of MOS. It was concluded that the use of growth promoters was beneficial to Increase intestinal villi height when Bacillus subtilis was used in combination with prebiotics. The other growth promoters (MOS+OA, MOS, and bacterial pool), can be individually used in most situations. The tested growth promoters did not influence intestinal villi density.

Yeast extract and prebiotic in pre-initial phase diet for broiler chickens raised under different temperatures

Objetivou-se nesta pesquisa avaliar o desempenho, o rendimento de carcaça e a morfometria intestinal de frangos de corte criados em diferentes temperaturas e que receberam na fase pré-inicial ração contendo ou não extrato de leveduras e prebiótico. Foram utilizados 1.440 pintos machos de 1 dia de idade, criados em diferentes câmaras climáticas. As rações, acrescidas ou não de extrato de leveduras e prebiótico, foram oferecidas somente na fase pré-inicial (1 a 7 dias). A partir do oitavo dia, todas as aves receberam a mesma ração, reajustada de acordo com as recomendações usuais. Adotou-se o delineamento experimental inteiramente casualizado em arranjo fatorial 3 × 2 × 2, composto de três temperaturas de criação (calor, conforto e frio) e dois níveis de extrato de leveduras (com ou sem) e prebiótico (com ou sem). O desempenho das aves foi avaliado considerando o ganho de peso, o consumo de ração, a conversão alimentar e a viabilidade aos 42 dias de idade. Também foram avaliados o rendimento de carcaça e a morfometria intestinal. O calor ambiente prejudicou o desempenho e o rendimento de carcaça. A inclusão de prebiótico na ração pré-inicial aumentou o ganho de peso e melhorou a conversão alimentar das aves criadas no calor. A inclusão dos produtos na ração de frangos de corte criados em ambiente de calor e no frio tem efeito benéfico sobre as vilosidades das aves.

Saccharomyces Cerevisiae cell wall dietary supplementation on the performance and intestinal mucosa development and integrity of broiler chickens vaccinated against coccidiosis

This study was carried out to verify if Saccharomyces cerevisiae cell wall (SCCW) dietary supplementation (0.2%) was capable of protecting the intestinal mucosa of broiler chickens vaccinated against coccidiosis. Body weight gain, feed intake, feed conversion and intestinal mucosa morphometric parameters and epithelial loss were evaluated. In the experiment,400 day-old male chicks were distributed according to a completely randomized design in a 2x2 factorial arrangement. The following treatments were applied: T1 - no vaccination/ no SCCW supplementation; T2 - no vaccination/SCCW supplementation; T3 - vaccination/no SCCW supplementation; and T4 - vaccination/SCCW supplementation to four replicates of 25 birds each. Birds were vaccinated on the first day of age using a spray vaccine (Coccivac B®, Coopers), containing E. acervulina, E. maxima, E. mivati and E. tenella. S. cerevisiae cell wall was supplied from the first day of age. Live performance, intestinal morphometric parameters and epithelial loss were evaluated at 14, 21 and 28 days of age. Performance was affected by vaccination only at 21-days of age, when body weight gain was reduced in the vaccinated birds, but no body weight difference was observed on day 28. Vaccine also increased the crypt depth (p<0.05) in the duodenum and jejunum, suggesting a high cell activity in the crypt:villus transition area to maintain the epithelial cell turnover. Villi number/area (103,269 µm²) was not affected (p>0.05) by vaccine or cell wall supplementation, and epithelial loss was more pronounced in the duodenum and jejunum. In conclusion, the findings of this study suggest that S. cerevisiae cell wall supplementation may be an useful management tool to maintain the intestinal integrity of broilers vaccinated against coccidiosis.

Influence of egg pre-storage heating period and storage length on the digestive tract of newly-hatched broiler chicks

An experiment was carried out to evaluate the effect of different heating times of settable eggs of Cobb 500® broiler breeders before submitting them to different storage periods on body weight, digestive tract organ weights, and intestinal mucosa morphology of newly-hatched chicks. Settable eggs were distributed in a completely randomized experimental design with a 3 x 3 factorial arrangement: pre-storage heating periods (0, 6, 12 hours at 36.92°C) and storage periods (4, 9, 14 days at 12.06°C). Body weight and relative weights of the yolk sac, heart, liver, proventriculus+gizzard, and intestinal segments were measured in chicks hatching at 480 and 498 hours of incubation. Villi height, width and perimeter, and crypt depth (ìm) were measured in duodenal histological sections. It was concluded that pre-storage heating for six hours of eggs stored for four or nine days increases small intestine weight of newly-hatched chicks, but does not influence the morphology of the duodenal mucosa. Pre-storage heating for 12 hours negatively influences body weight and duodenal mucosa development, and therefore this practice is not recommended. Storage length does not have consistent effect on body weight and development of the gastrointestinal tract.

Use of scanning electron microscopy for the evaluation of intestinal epithelium integrity

Propõe-se, neste trabalho, o uso de microscopia eletrônica de varredura para avaliar perda de epitélio intestinal da mucosa intestinal de pintos machos e fêmeas submetidos a prolongado jejum pós-eclosão de água e ração. Dois segmentos do duodeno, jejuno e íleo por ave foram coletados e processados pelo método de rotina para microscopia eletrônica de varredura. Seis diferentes graus de perda de epitélio intestinal foram determinados: grau 0, vilos normais, sem extrusão; grau 1, vilos com pequenos pontos de extrusão; grau 2, vilos com perda de epitélio no ápice; grau 3, vilos com perda de epitélio na região apical; grau 4, vilos com perda de epitélio em sua metade superior; grau 5: vilos sem epitélio; grau 6: vilo quebrado. As três regiões intestinais das fêmeas apresentaram aproximadamente 90% de seus vilos normais (graus 0 e 1), enquanto nos machos ocorreu 38% de vilos normais no duodeno e jejuno e 85% no íleo. Além disso, machos apresentaram graus mais acentuados de perda de epitélio (graus 3, 4, 5 e 6) que as fêmeas (grau 3). Os dados indicaram que a mucosa intestinal de pintos machos é mais sensível a prolongado jejum pós-eclosão que a de pintos fêmeas. A microscopia eletrônica de varredura pode ser usada como um método de rotina seguro para a caracterização e quantificação de perda de epitélio intestinal.

Alterações ultraestruturais nas vilosidades do jejuno de equinos após distensão

O objetivo do presente estudo foi analisar as alterações ultraestruturais nas vilosidades do jejuno de seis equinos submetidos à distensão intraluminal com solução salina. A pressão intraluminal foi mantida em 25cm de água durante duas horas. As amostras de mucosa intestinal colhidas às: zero hora; duas horas de distensão; e duas horas e 12h de descompressão foram analisadas por meio de microscopia eletrônica de varredura. Avaliaram-se a área e o perímetro das vilosidades e sua densidade, usando-se um programa computacional de análise de imagens (Image J). A distensão luminal promoveu aumentos da área e do perímetro das vilosidades intestinais. Essa alteração ultraestrutural ocorreu somente 12h após a descompressão e considerou-se que a provável causa seria o edema promovido por aumento da permeabilidade vascular decorrente de um processo de isquemia e reperfusão da mucosa intestinal. Concluiu-se que a distensão intraluminal do jejuno equino promoveu, tardiamente, aumento das dimensões das vilosidades intestinais.

Mananoligossacarídeos e complexo enzimático em dietas para frangos de corte

Avaliou-se o efeito de dietas com mananoligossacarídeos e complexo enzimático (CE) sobre o desempenho, a morfologia intestinal e a qualidade da cama de frangos aos 42 dias de idade. Foram utilizadas 750 aves em delineamento inteiramente casualizado em esquema fatorial 2 × 2 + 1, com dois níveis de mananoligossacarídeos (0 e 0,1% de 1 a 21 dias e 0,05% de 22 a 42 dias de idade), dois níveis de complexo enzimático (0 e 0,05%) e uma dieta com antibióticos (CP), totalizando cinco dietas com cinco repetições. Aos 42 dias de criação, o desempenho foi avaliado e, após o abate das aves, foram coletadas amostras de intestino e de cama e avaliado o desempenho. A inclusão de mananoligossacarídeos e/ou complexo enzimático na dieta não afetou o desempenho das aves, o perímetro e a altura dos vilos duodenais, a profundidade de criptas, a densidade de vilos no duodeno, jejuno e íleo, os teores de matéria seca e nitrogênio total e o pH das camas. A interação mananoligossacarídeos × complexo enzimático foi significativa para perímetro e altura de vilos no jejuno, que foram maiores nas aves alimentadas com as rações sem complexo enzimático e mananoligossacarídeos, mesmo comportamento observado para perímetro e altura de vilos ileais. Entretanto, quando adicionados mananoligossacarídeos e complexo enzimático, os valores dessas variáveis reduziram. A volatilização de amônia aumentou em camas de frango tratados com antibióticos e diminuiu com a adição de mananoligossacarídeos à dieta. A adição de mananoligossacarídeos ou complexo enzimático às dietas aumentou o perímetro e altura de vilos da mucosa do jejuno e do íleo e reduziu a volatilização de amônia da cama.

Effects of corn particle size and physical form of the diet on the gastrointestinal structures of broiler chickens

The objective of this experiment was to investigate the effects of different particle sizes, expressed as Geometric Mean Diameter (GMD) of corn (0.336mm, 0.585mm, 0.856mm and 1.12mm) of mash and pelleted broiler chicken diets on the weight of the gizzard, duodenum and jejunum+ileum; on the pH of the gizzard and small intestine and on the characteristics of the duodenal mucous layer (number and height of villi and crypt depth) in 42-day-old broilers. The physical form and the particle size of the diet had no significant effect on gizzard and intestine pH (p > 0.05). A greater gizzard weight was seen in the birds receiving pelleted diet and particle size of 0.336mm (p < 0.008). However, for the particle sizes of 0.856 and 1.12 mm, a greater weight was found in birds that received mash diet (p < 0.039 and p < 0.006, respectively). Also, gizzard weight was greater with increasing corn GMD independent of the physical form of the diet. In the mash diet, the increase in particle size promoted a quadratic response in the weight of duodenum and jejunum + ileum. The pelleted diet promoted a greater number of villi per transverse duodenum cut (p < 0.007) and greater crypt depth (p < 0.05). As the particle size increased, there was a linear increase of villus height and crypt depth in the duodenum, irrespective of the physical form of the diet.

Effect of probiotic and prebiotic inclusion in weaned piglet diets on structure and ultra-structure of small intestine

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Utilização de dietas úmidas e de rações e água de bebida com edulcorante para leitões desmamados aos 21 dias de idade e efeitos sobre o desenvolvimento histológico e enzimático intestinal

Um experimento foi realizado com leitões desmamados visando avaliar os efeitos de oito tratamentos, correspondentes à combinação dos fatores, apresentações de ração (seca e úmida), tipos de ração (sem e com edulcorante) e tipos de água de consumo (sem e com edulcorante) sobre o desenvolvimento morfológico e enzimático intestinal. Foram avaliadas a altura das vilosidades (V), a profundidade das criptas (C) e a relação altura das vilosidades e profundidade das criptas (V:C) do duodeno e do jejuno, o conteúdo de proteína na mucosa do jejuno, e as atividades enzimáticas (UA) da maltase, sacarase e dipeptidase. Utilizaram-se 32 leitões machos castrados, Large White x Landrace, desmamados aos 21 dias, submetidos aos tratamentos durante oito dias. O delineamento experimental foi em blocos casualizados, com oito tratamentos, fatorial 2 x 2 x 2, com quatro repetições. Foram observadas diferenças para a altura das vilosidades do duodeno para os grupos tratados com dieta úmida e ração com edulcorante e para a relação V:C do duodeno para os animais que receberam ração com edulcorante. Houve diferença para a UA da sacarase e da maltase para os grupos que receberam água sem edulcorante. As características histológicas foram favorecidas pelas dietas úmidas, o que pode sugerir que esta apresentação foi menos agressiva ao trato digestivo. Para os demais fatores os resultados contrariaram as expectativas de que o tratamento água com edulcorante melhoraria a qualidade do epitélio intestinal. A fase crítica pela qual os leitões foram submetidos, possivelmente, comprometeu os resultados.