The effects of maternal hyperglycemia on human umbilical vascular gene expression and neonatal rat lung development

Background: Maternal diabetes affects many fetal organ systems, including the vasculature and the lungs. The offspring of diabetic mothers have respiratory adaptation problems after birth. The mechanisms are multifactorial and the effects are prolonged during the postnatal period. An increasing incidence of diabetic pregnancies accentuates the importance of identifying the pathological mechanisms, which cause the metabolic and genetic changes that occur in offspring, born to diabetic mothers. Aims and methods: The aim of this thesis was to determine changes both in human umbilical cord exposed to maternal type 1 diabetes and in neonatal rat lungs after streptozotocin-induced maternal hyperglycemia, during pregnancy. Rat lungs were used as a model for the potential disease mechanisms. Gene expression alterations were determined in human umbilical cords at birth and in rat pup lungs at two week of age. During the first two postnatal weeks, rat lung development was studied morphologically and histologically. Further, the effect of postnatal hyperoxia on hyperglycemia-primed rat lungs was investigated at one week of age to mimic the clinical situation of supplemental oxygen treatment. Results: In the umbilical cord, maternal diabetes had a major negative effect on the expression of genes involved in blood vessel development. The genes regulating vascular tone were also affected. In neonatal rat lungs, intrauterine hyperglycemia had a prolonged effect on gene expression during late alveolarization. The most affected pathway was the upregulation of extracellular matrix proteins. Newborn rat lungs exposed to intrauterine hyperglycemia had thinner saccular walls without changes in airspace size, a smaller relative lung weight and lung total tissue area, and increased cellular apoptosis and proliferation compared to control lungs, possibly reflecting an aberrant maturational adaptation. At one and two weeks of age, cell proliferation and secondary crest formation were accelerated in hyperglycemia-exposed lungs. Postnatal hyperoxic exposure, alone caused arrested alveolarization with thin-walled and enlarged alveoli. In contrast, the dual exposure of intrauterine hyperglycemia and postnatal hyperoxia resulted in the phenotype of thick septa together with arrested alveolarization and decreased number of small pulmonary arteries. Conclusions: Maternal diabetic environment seems to alter the umbilical cord gene expression profile of the regulation of vascular development and function. Fetal hyperglycemia may additionally affect the genetic regulation of the postnatal lung development and may actually induce prolonged structural alterations in neonatal lungs together with a modifying effect on the deleterious pulmonary exposure of postnatal hyperoxia. This, combined with the novel human umbilical cord gene data could serve as stepping stones for future therapies to curb developmental aberrations.

Evaluation of an e-learning course: coercion practices in psychiatric nursing

The goal of the study was to evaluate an e-learning course entitled “Nursing interventions to manage distressed and disturbed patients” and intended for psychiatric nurses, using Kirkpatrick’s evaluation model. The aim was to describe nurses’ reactions, learning, behaviour change and impacts resulting from this e-learning course. This dissertation comprises four papers, and the data were collected 2008-2012 from three different sources; electronic databases, an e-learning platform and psychiatric hospitals. First, a systematic literature review was conducted to understand the effectiveness of e-learning. Second, an RCT study was implemented to investigate the impact of the e-learning course on nurses’ job-satisfaction, knowledge and attitudes (N=158). Third, to complete the picture of nurses views of the e-learning course related to knowledge transfer, the nurses’ perspective was studied (N=33). Lastly, the effects of the e-learning course from nursing managers’ perspective in psychiatric hospital organisations were studied (N=28). The systematic review showed that although the nurses were satisfied with the e-learning, no effects were found in the RCT study of nurses’ job satisfaction. The RCT study showed no effects on nurses’ learning related to knowledge increase, but there was change in attitudes. The managers described the changes in the nurses’ knowledge and attitudes. Among the nurses behaviour changed with knowledge transfer from the e-learning course to practice and they pointed out development issues related to their work. The final impacts of the e-learning course revealed advantages and disadvantages of the e-learning course and its implications for nurses’ work. This dissertation provides new insight into nurses’ reactions, learning, behaviour change and impacts resulting from an e-learning course in their continuing education. In order to improve nurses’ continuing education systematic evaluation is needed, for which Kirkpatrick’s evaluation model is a useful tool.

Synergistic effect of glucose and prolactin on GLUT2 expression in cultured neonatal rat islets

We studied the synergistic effect of glucose and prolactin (PRL) on insulin secretion and GLUT2 expression in cultured neonatal rat islets. After 7 days in culture, basal insulin secretion (2.8 mM glucose) was similar in control and PRL-treated islets (1.84 ± 0.06% and 2.08 ± 0.07% of the islet insulin content, respectively). At 5.6 and 22 mM glucose, insulin secretion was significantly higher in PRL-treated than in control islets, achieving 1.38 ± 0.15% and 3.09 ± 0.21% of the islet insulin content in control and 2.43 ± 0.16% and 4.31 ± 0.24% of the islet insulin content in PRL-treated islets, respectively. The expression of the glucose transporter GLUT2 in B-cell membranes was dose-dependently increased by exposure of the islet to increasing glucose concentrations. This effect was potentiated in islets cultured for 7 days in the presence of 2 µg/ml PRL. At 5.6 and 10 mM glucose, the increase in GLUT2 expression in PRL-treated islets was 75% and 150% higher than that registered in the respective control. The data presented here indicate that insulin secretion, induced by different concentrations of glucose, correlates well with the expression of the B-cell-specific glucose transporter GLUT2 in pancreatic islets

Aversive stimulation during the stress-hyporesponsive period does not affect the number of corticotroph cells in neonatal male rats

Immunohistochemistry was used to evaluate the effects of neonatal handling and aversive stimulation during the first 10 days of life on the number of corticotrophs in the anterior lobe of the pituitary of 11-day-old male Wistar rats. Since adult rats handled during infancy respond with reduced corticosterone secretion in response to stressors and with less behavior inhibition in novel environments, we assumed that neonatal stimulation could affect pituitary morphology during this critical period of cell differentiation. Three groups of animals were studied: intact (no manipulation, N = 5), handled (N = 5) and stimulated (submitted to 3 different aversive stimuli, N = 5). The percentage of ACTH-immunoreactive cells in the anterior lobe of the pituitary (number of ACTH-stained cells divided by total number of cells) was determined by examining three slices per pituitary in which a minimum of 200 cells were counted by two independent researchers. Although animals during the neonatal period are less reactive to stress-like stimulation in terms of ACTH and corticosterone secretion, results showed that the relative number of ACTH-stained cells of neonatal handled (0.25 ± 0.01) and aversive stimulated (0.29 ± 0.03) rats was not significantly different from intact (0.30 ± 0.03) animals. Neonatal stimulation may have a differential effect on the various subpopulations of corticotroph cells in the anterior pituitary

Development of the insulin secretion mechanism in fetal and neonatal rat pancreatic B-cells: response to glucose, K+, theophylline, and carbamylcholine

We studied the development of the insulin secretion mechanism in the pancreas of fetal (19- and 21-day-old), neonatal (3-day-old), and adult (90-day-old) rats in response to stimulation with 8.3 or 16.7 mM glucose, 30 mM K+, 5 mM theophylline (Theo) and 200 µM carbamylcholine (Cch). No effect of glucose or high K+ was observed on the pancreas from 19-day-old fetuses, whereas Theo and Cch significantly increased insulin secretion at this age (82 and 127% above basal levels, respectively). High K+ also failed to alter the insulin secretion in the pancreas from 21-day-old fetuses, whereas 8.3 mM and 16.7 mM glucose significantly stimulated insulin release by 41 and 54% above basal levels, respectively. Similar results were obtained with Theo and Cch. A more marked effect of glucose on insulin secretion was observed in the pancreas of 3-day-old rats, reaching 84 and 179% above basal levels with 8.3 mM and 16.7 mM glucose, respectively. At this age, both Theo and Cch increased insulin secretion to close to two-times basal levels. In islets from adult rats, 8.3 mM and 16.7 mM glucose, Theo, and Cch increased the insulin release by 104, 193, 318 and 396% above basal levels, respectively. These data indicate that pancreatic B-cells from 19-day-old fetuses were already sensitive to stimuli that use either cAMP or IP3 and DAG as second messengers, but insensitive to stimuli such as glucose and high K+ that induce membrane depolarization. The greater effect of glucose on insulin secretion during the neonatal period indicates that this period is crucial for the maturation of the glucose-sensing mechanism in B-cells.

Histopathological diagnosis of intra- and extrahepatic neonatal cholestasis

The histopathology of the liver is fundamental for the differential diagnosis between intra- and extrahepatic causes of neonatal cholestasis. However, histopathological findings may overlap and there is disagreement among authors concerning those which could discriminate between intra- and extrahepatic cholestasis. Forty-six liver biopsies (35 wedge biopsies and 11 percutaneous biopsies) and one specimen from a postmortem examination, all from patients hospitalized for neonatal cholestasis in the Pediatrics Service of Hospital de Clínicas de Porto Alegre, were prospectively studied using a specially designed histopathological protocol. At least 4 of 5 different stains were used, and 46 hepatic histopathological variables related to the differential diagnosis of neonatal cholestasis were studied. The findings were scored for severity on a scale from 0 to 4. Sections which showed less than 3 portal spaces were excluded from the study. Sections were examined by a pathologist who was unaware of the final diagnosis of each case. Bile tract permeability was defined by scintigraphy of the bile ducts and operative cholangiography. The F test and discriminant analysis were used as statistical methods for the study of the hepatic histopathological variables. The chi-square method with Yates correction was used to relate the age of the patients on the date of the histopathological study to the discriminatory variables between intra- and extrahepatic cholestasis selected by the discriminant function test. The most valuable hepatic histopathological variables for the discrimination between intra- and extrahepatic cholestasis, in decreasing order of importance, were periportal ductal proliferation, portal ductal proliferation, portal expansion, cholestasis in neoductules, foci of myeloid metaplasia, and portal-portal bridges. The only variable which pointed to the diagnosis of intrahepatic cholestasis was myeloid metaplasia. Due to the small number of patients who were younger than 60 days on the date of the histopathological study (N = 6), no variable discriminated between intra- and extrahepatic cholestasis before the age of 2 months and all of them, except for the portal expansion, were discriminatory after this age. In infants with cholestasis, foci of myeloid metaplasia, whenever present in the liver biopsy, suggested intrahepatic cholestasis. Periportal ductal proliferation, portal ductal proliferation, portal expansion, cholestasis in neoductules, portal cholestasis and portal-portal bridges suggested extrahepatic obstructive cholestasis.

Effects of sciatic-conditioned medium on neonatal rat retinal cells in vitro

Schwann cells produce and release trophic factors that induce the regeneration and survival of neurons following lesions in the peripheral nerves. In the present study we examined the in vitro ability of developing rat retinal cells to respond to factors released from fragments of sciatic nerve. Treatment of neonatal rat retinal cells with sciatic-conditioned medium (SCM) for 48 h induced an increase of 92.5 ± 8.8% (N = 7 for each group) in the amount of total protein. SCM increased cell adhesion, neuronal survival and glial cell proliferation as evaluated by morphological criteria. This effect was completely blocked by 2.5 µM chelerythrine chloride, an inhibitor of protein kinase C (PKC). These data indicate that PKC activation is involved in the effect of SCM on retinal cells and demonstrate that fragments of sciatic nerve release trophic factors having a remarkable effect on neonatal rat retinal cells in culture.

A laboratory cage for foster nursing newborn mice

We describe a cage to be used for foster nursing in order to guarantee that original mother's colostrum is not ingested by the newborn mice. A common (30.5 cm x 19.5 cm x 12.0 cm) mouse cage was fitted with a wire net tray with a mesh (1 cm x 1 cm), which divides the cage into an upper and a lower compartment. Mice born to females placed in the upper compartment pass through the mesh and fall into the lower compartment, where another lactating female with one or two of its own pups are. Of a total of 28 newborn mice of C3H/He and Swiss strains, 23 were successfully fostered. Important observations are presented to show that this is a valuable alternative for foster studies without great suffering on the part of the female.

Neonatal handling induces anovulatory estrous cycles in rats

Since previous work has shown that stimulation early in life decreases sexual receptiveness as measured by the female lordosis quotient, we suggested that neonatal handling could affect the function of the hypothalamus-pituitary-gonadal axis. The effects of neonatal handling on the estrous cycle and ovulation were analyzed in adult rats. Two groups of animals were studied: intact (no manipulation, N = 10) and handled (N = 11). Pups were either handled daily for 1 min during the first 10 days of life or left undisturbed. At the age of 90 days, a vaginal smear was collected daily at 9:00 a.m. and analyzed for 29 days; at 9:00 a.m. on the day of estrus, animals were anesthetized with thiopental (40 mg/kg, ip), the ovaries were removed and the oviduct was dissected and squashed between 2 glass slides. The number of oocytes of both oviductal ampullae was counted under the microscope. The average numbers for each phase of the cycle (diestrus I, diestrus II, proestrus and estrus) during the period analyzed were compared between the two groups. There were no significant differences between intact and handled females during any of the phases. However, the number of handled females that showed anovulatory cycles (8 out of 11) was significantly higher than in the intact group (none out of 10). Neonatal stimulation may affect not only the hypothalamus-pituitary-adrenal axis, as previously demonstrated, but also the hypothalamus-pituitary-gonadal axis in female rats.

Stimulatory effect of dexamethasone on angiotensin-converting enzyme in neonatal rat cardiac myocytes

Angiotensin-converting enzyme (ACE) plays a central role in cardiac remodeling associated with pathological conditions such as myocardial infarction. The existence of different cell types in the heart expressing components of the renin-angiotensin system makes it difficult to evaluate their relative role under physiological and pathological conditions. Since myocytes are the predominant cellular constituent of the heart by mass, in the present study we studied the effects of glucocorticoids on ACE activity using well-defined cultures of neonatal rat cardiac myocytes. Under steady-state conditions, ACE activity was present at very low levels, but after dexamethasone treatment ACE activity increased significantly (100 nmol/l after 24 h) in a time-dependent fashion. These results demonstrate the influence of dexamethasone on ACE activity in rat cardiac myocytes. This is consistent with the idea that ACE activation occurs under stress conditions, such as myocardial infarction, in which glucocorticoid levels may increase approximately 50-fold.

Reduction of intraspecific aggression in adult rats by neonatal treatment with a selective serotonin reuptake inhibitor

Most studies suggest that serotonin exerts an inhibitory control on the aggression process. According to experimental evidence, this amine also influences growth and development of the nervous tissue including serotoninergic neurons. Thus, the possibility exists that increased serotonin availability in young animals facilitates a long-lasting effect on aggressive responses. The present study aimed to investigate the aggressive behavior of adult rats (90-120 days) treated from the 1st to the 19th postnatal day with citalopram (CIT), a selective serotonin reuptake inhibitor (20 mg/kg, sc, every 3 days). Aggressive behavior was induced by placing a pair of rats (matched by weight) in a box (20 x 20 x 20 cm), and submitting them to a 20-min session of electric footshocks (five 1.6-mA - 2-s current pulses, separated by a 4-min intershock interval). When compared to the control group (rats treated for the same period with equivalent volumes of saline solution), the CIT group presented a 41.4% reduction in the duration of aggressive response. The results indicate that the repeated administration of CIT early in life reduces the aggressive behavior in adulthood and suggest that the increased brain serotoninergic activity could play a role in this effect.

The Impact of Neonatal Antibiotic Exposure on Atopic Sensitisation by the Age of 12 Months

Varhaislapsuuden antibioottialtistuksen vaikutus atooppiseen herkistymiseen 12 kuukauden ikään mennessä Bakteerien vaikutus terveyteen on merkittävä: ne ovat toisaalta hengenvaarallisten infektioiden aiheuttajia, mutta samanaikaisesti niiden läsnäolo on välttämätöntä terveen immuunipuolustuksen kehittymiseksi. Ensimmäisen elinvuoden aikana suoliston bakteerikanta on altis ulkoisten tekijöiden vaikutuksille. Varhaislapsuuden antibioottihoidolla voi olla tuhoisat seuraukset eri bakteerilajien suhteille, ja sen tiedetään altistavan erilaisille immuunivälitteisille sairauksille, kuten atopialle. Ei ole kuitenkaan selvitetty, onko tämä vaikutus johtunut käynnissä olevan infektion aiheuttamista muutoksista kehittyvään immuunijärjestelmään vai onko siihen ollut syynä infektioon aloitettu antibioottihoito. Tässä tutkimuksessa selvitettiin eroja kahden, varhaista antibioottihoitoa saaneen ryhmän välillä ja päätetapahtumaksi katsottiin myöhemmin lapsuudessa ilmenevä atopiataipumus. Toinen ryhmä sai antibioottihoitoa kliinisesti todistettuun bakteeri-infektioon (varhaiseen sepsikseen). Toinen ryhmä taas sai antibioottihoidon pelkästään infektioepäilyyn eli ns. empiirisen hoidon, joka lopetettiin alle viiden vuorokauden kuluessa kun katsottiin, ettei oireiden taustalla ollutkaan bakteeri-infektiota. Mukana vertailussa oli lisäksi ryhmä, joka ei saanut lainkaan varhaista antibioottihoitoa. Antibioottihoidon pitkäaikaisvaikutusta arvioitiin ihon prick-testillä, joka kertoo atopiaan liittyvästä IgE-välitteisestä herkistymisestä. Varhaisella antibioottihoidolla tarkoitetaan tässä alle 72 tunnin sisällä syntymästä alkanutta hoitoa G-penisilliinin ja gentamysiinin yhdistelmällä. Tutkimuksen aineisto koostui 755 vastasyntyneen lapsen seurantadatasta, joka saatiin neljän käynnissä olevan allergian ehkäisytutkimuksen aineistosta. Tutkimuksen mukaanottokriteereinä pidettiin sitä, että saatavilla oli tiedot sekä mahdollisen antibioottialtistuksen kestosta että ihon prick-testituloksesta joko 6 tai 12 kuukauden iässä. Tulokset analysoitiin logistisella regressioanalyysillä huomioiden mahdolliset sekoittavat tekijät: äidin allergia, ennenaikaisuus, tutkimusprobiootti, imetyksen kesto, äidin raskauden aikainen tupakointi ja synnytystapa. Potilasryhmässä, joka sai antibioottihoitoa ilman samanaikaista infektiota, nähtiin tilastollisesti merkittävästi vähemmän positiivisia prick-testituloksia verrattuna lapsiin, jotka eivät altistuneet antibiooteille. Tulos on merkittävä, sillä se osoittaa, että varhaisella antibioottihoidolla on kauaskantoisia vaikutuksia kehittyvään immuunijärjestelmään.

Reliability and validity of the interactive observation scale for psychiatric inpatients applied by nursing aides in daily ward practice

The main characteristic of the nursing Interactive Observation Scale for Psychiatric Inpatients (IOSPI) is the necessity of interaction between raters and patients during assessment. The aim of this study was to evaluate the reliability and validity of the scale in the "real" world of daily ward practice and to determine whether the IOSPI can increase the interaction time between raters and patients and influence the raters' opinion about mental illness. All inpatients of a general university hospital psychiatric ward were assessed daily over a period of two months by 9 nursing aides during the morning and afternoon shifts, with 273 pairs of daily observations. Once a week the patients were interviewed by a psychiatrist who filled in the Brief Psychiatric Rating Scale (BPRS). The IOSPI total score was found to show significant test-retest reliability (interclass correlation coefficient = 0.83) and significant correlation with the BPRS total score (r = 0.69), meeting the criteria of concurrent validity. The instrument can also discriminate between patients in need of further inpatient treatment from those about to be discharged (negative predictive value for discharge = 0.91). Using this scale, the interaction time between nursing aides and patients increased significantly (t = 2.93, P<0.05) and their opinion about the mental illness changed. The "social restrictiveness" factor of the opinion scale about mental illness showed a significant reduction (t = 4.27, P<0.01) and the "interpersonal etiology" factor tended to increase (t = 1.98, P = 0.08). The IOSPI was confirmed as a reliable and valid scale and as an efficient tool to stimulate the therapeutic attitudes of the nursing staff.

Neonatal handling and the expression of immunoreactivity to tyrosine hydroxylase in the hypothalamus of adult male rats

Neonatal handling has long-lasting effects on behavior and stress reactivity. The purpose of the present study was to investigate the effect of neonatal handling on the number of dopaminergic neurons in the hypothalamic nuclei of adult male rats as part of a series of studies that could explain the long-lasting effects of neonatal stimulation. Two groups of Wistar rats were studied: nonhandled (pups were left undisturbed, control) and handled (pups were handled for 1 min once a day during the first 10 days of life). At 75-80 days, the males were anesthetized and the brains were processed for immunohistochemistry. An anti-tyrosine hydroxylase antibody and the avidin-biotin-peroxidase method were used. Tyrosine hydroxylase-immunoreactive (TH-IR) neurons were counted bilaterally in the arcuate, paraventricular and periventricular nuclei of the hypothalamus in 30-µm sections at 120-µm intervals. Neonatal handling did not change the number of TH-IR neurons in the arcuate (1021 ± 206, N = 6; 1020 ± 150, N = 6; nonhandled and handled, respectively), paraventricular (584 ± 85, N = 8; 682 ± 62, N = 9) or periventricular (743 ± 118, N = 7; 990 ± 158, N = 7) nuclei of the hypothalamus. The absence of an effect on the number of dopaminergic cells in the hypothalamus indicates that the reduction in the amount of neurons induced by neonatal handling, as shown by other studies, is not a general phenomenon in the brain.

Nurse Competence of Graduating Nursing Students

The competence of graduating nursing students is an important issue in health care as it is related to professional standards, patient safety and the quality of nursing care. Many changes in health care lead to increased demand with respect to nurses’ competence as well the number of nurses. The purpose of this empirical study was to i) describe the nurse competence areas of nursing students in Europe, ii) evaluate the nurse competence of graduating nursing students, iii) identify factors related to the nurse competence, and to iv) assess the congruence between graduating nursing students’ self-assessments and their mentors’ assessments of students’ nurse competence. The study was carried out in two phases: descriptive phase and evaluation phase. The descriptive phase focused on describing the nurse competence areas of nursing students in Europe with the help of a literature review (n=10 empirical studies and n=4 additional documents). Thematic analysis was used as the analysis method. In the evaluation phase, the nurse competence with particular focus on nursing skills of graduating nursing students (n=154) was assessed. In addition, factors related to the nurse competence were examined. Also, the congruence between graduating nursing students’ self-assessments and their mentors’ assessments of students’ nurse competence was evaluated by comparing graduating nursing students’ self-assessments with the assessments by their mentors (n=42) in the final clinical placement in four university hospitals. Descriptive statistics and inferential statistics were used to analyse the data. Based on the results, the nurse competence of nursing students in Europe consists of nine main competence areas: (1) professional/ethical values and practice, (2) nursing skills and interventions, (3) communication and interpersonal skills, (4) knowledge and cognitive ability, (5) assessment and improving quality in nursing, (6) professional development, (7) leadership, management and teamwork, (8) teaching and supervision, and (9) research utilization. Graduating nursing students self-assessed their nurse competence as good. However, when graduating nursing students’ nurse competence was assessed by their mentors, the results were poorer. Readiness for practice based on nurse education, pedagogical atmosphere on the ward, supervisory relationship between student and mentor and being in paid work in health care at the moment of the study were the most significant factors related to the nurse competence. Conclusions: Nurse competence can be evaluated with a scale based on self-assessment, but other evaluation methods could be used alongside to ensure that nurse competence can be completed and evaluated critically. Practical implications are presented for nurse education and nursing practice. In future, longitudinal research is needed in order to understand the development of nurse competence during nurse education and the transition process from a nursing student to a professional nurse.