L Group (l + group)

Distribution by Scientific Domains


Selected Abstracts


Effectiveness of dental trauma education for elementary school staff

DENTAL TRAUMATOLOGY, Issue 2 2008
Judy D. McIntyre
Using a newly developed reliable survey instrument, we tested our elementary school staff participants about TDI before (time0), immediately after (time1), and three months after (time2) the intervention. Schools were randomized into three groups: no intervention/control (C), pamphlets (P), and pamphlets + lecture (P + L). Outcomes of interest were TDI knowledge over time relative to the interventions vs controls. Statistical analysis involved a repeated measures linear model. At time0, TDI knowledge was low among all three groups. At time1, knowledge increased among all groups and is given by P > P+L > C. For time2 vs time1, the P + L group retained the knowledge while in both the C and P groups the knowledge level decreased. Between time1 and time2, significant differences were found between both intervention groups when compared with the control (P vs C and P + L vs C: both P < 0.05). In summary, both P and P + L groups significantly improved TDI knowledge among elementary school staff, and this difference held up over time. These interventions have the potential to improve TDI management by elementary school staff when faced with such injuries. [source]


Nitric oxide and thyroid gland: modulation of cardiovascular function in autonomic-blocked anaesthetized rats

EXPERIMENTAL PHYSIOLOGY, Issue 3 2004
Andrea Lorena Fellet
We have previously reported that acute administration of NG -nitro- l -arginine methyl ester (l -NAME) increases the mean arterial pressure (MAP) and heart rate (HR) in autonomic-blocked (CAB) anaesthetized rats. In the present study we examined whether thyroid and adrenal glands are involved in these pressor and chronotropic responses. Sprague-Dawley rats were studied after bilateral vagotomy and ganglionic blockade with hexamethonium (10 mg kg,1), and stabilization of MAP with infusion of phenylephrine (PE) (6 ,g kg,1 min,1). The rats were divided into groups: L, CAB; PE, CAB + PE bolus (6 ,g kg,1); L-TX, thyroidectomy + CAB; L-AX, adrenalectomy + CAB; TX, only thyroidectomy; C, CAB. L, L-AX and L-TX groups received a bolus of l -NAME (7.5 mg kg,1). Triiodothyronine (T3), thyroxin (T4) and thyrotropin (TSH) levels were measured in L and L-TX rats before and after l -NAME administration. Reduced nicotamide adenine dinucleotide (NADPH) diaphorase activity was determined in heart and aorta of the TX group. The pressor response induced by l -NAME was similar in all groups. l -NAME-induced-tachycardia was associated with this rise in MAP. Adrenalectomy did not modify this chronotropic response, but it was attenuated by thyroidectomy. Thyroidectomy by itself decreased the circulating levels of T3 but it had no effect on the plasma levels of T4 and TSH. L and L-TX groups showed similar levels of circulating T4 and TSH, meanwhile the plasma level of T3 decreased in the L group. Nitric oxide synthase (NOS) activity in atria as well as in aorta was greater in the TX group compared with C. When autonomic influences are removed, the thyroid gland modulates intrinsic heart rate via a mechanism that involves, at least in part, the nitric oxide pathway. [source]


Ovarian steroids and premenstrual symptoms: A comparison of group differences and intra-individual patterns

RESEARCH IN NURSING & HEALTH, Issue 3 2007
Martha J. Lentz
Abstract To examine the relationship of gonadal hormone and symptom patterns across the menstrual cycle, women screened for 2,3 cycles completed an intensive study cycle; 26 had a low-severity symptoms (LS), 20, a premenstrual syndrome (PMS), and 26, a premenstrual magnification pattern (PMM). All completed daily symptom diaries and collected late afternoon urine samples which were assayed for pregnanediol and estradiol for that cycle. The PMS and PMM groups had significantly more positive cross-correlations of pregnanediol and symptoms than the LS group. Women in all groups had similar levels of estradiol and pregnanediol. Women with PMS and PMM patterns responded to progesterone differently than women with LS patterns: thus the former groups may not benefit from hormone therapies. © 2007 Wiley Periodicals, Inc. Res Nurs Health 30: 238,249, 2007 [source]


Advanced fluorescence in situ hybridization to localize and quantify gene expression in Japanese medaka (Oryzias latipes) exposed to endocrine-disrupting compounds

ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 9 2009
June-Woo Park
Abstract In an earlier study, we described the development of fluorescence in situ hybridization (FISH) using confocal microscopy to localize and quantify gene expression in fish. Here, we report the results of FISH application to investigate effects of model endocrine-disrupting chemicals (EDCs), 17,-ethinylestradiol (EE2) and 17,-trenbolone (TB), on expressions of EDC-responsive genes in Japanese medaka (Oryzias latipes) at the cellular/tissue level paired with histological observation. Gene expressions of vitellogenin-II (Vit-II), androgen receptor (AR), and cytochrome P450 gonadal aromatase (CYP19a) were determined after exposure to 5, 50, or 500 ng/L of EE2 or 50, 500, or 5,000 ng/L of TB for 7 d. Exposure to the greatest concentration of EE2 or TB significantly reduced fecundity and caused histological alterations in gonads. 17,-Ethinylestradiol induced Vit-II expression in both male gonads and liver relative to controls and resulted in greater intensity of hematoxylin staining in hepatocytes, which was significantly correlated with Vit-II induction in liver. When exposed to EE2 at less than 50 ng/L, CYP19a expression associated with early stage oocytes was greater than that in controls. However, at 500 ng/L, this trend was reversed. The greater Vit-II expression in testis from all EE2 groups, and the lesser expression of CYP19a in ovaries from the 500 ng/L group, likely is related to changes in the number of cells in which these genes are predominantly expressed rather than to an increase in expression per cell. 17,-Trenbolone significantly induced AR expression in ovaries but did not alter AR expression in female liver. It was concluded that FISH combined with histology enables advanced elucidation of molecular effects of chemicals by associating changes in gene expression with certain tissues and/or cell types and allows these changes to be related to histological effects. [source]