Thrombocytopenia in Preterm Infants with Intrauterine Growth Restriction

Sick preterm infants often have thrombocytopenia at birth, and this is often associated with intrauterine growth restriction (IUGR), or birth weights less than the 10th percentile. The pathogenesis of the thrombocytopenia and its importance in IUGR are still unclear. We studied the characteristics of preterm IUGR infants with thrombocytopenia. Twenty-seven singleton Japanese preterm IUGR infants were born between January 2002 and June 2007 at Okayama University Hospital. Infants with malformation, chromosomal abnormalities, alloimmune thrombocytopenia, sepsis, and maternal aspirin ingestion were excluded. The infants were divided into group A (n&#65309;8), which had thrombocytopenia within 72h after birth, and group B (n&#65309;19), which did not. There were significant differences in birth weight, head circumference, umbilical artery (UA)-pulsatility index (PI), middle cerebral artery-PI, UA-pH, UA-pO2, and UA-pCO2. The infants in group A were smaller, had abnormal blood flow patterns, and were hypoxic at birth. We speculate that the infants with thrombocytopenia were more severely growth-restricted by chronic hypoxia. Thrombocytopenia is an important parameter for chronic hypoxia in the uterine.</p

c-fos Gene Expression in Postnatal Rat Retinas with Light/Dark Cycle

AbstractWe examined the diurnal variation of c-fos gene expression during a 12:12 light/dark cycle in developing rat retinas by in situ hybridization histochemistry. c-fos Gene was not expressed before postnatal day 10 (P10) but was expressed on P15 in the outer nuclear layer throughout the dark period and in the inner nuclear layer and the ganglion cell layer during the light period. These results demonstrated that the earliest c-fos gene expression occurred between P11 and P15. The good correlation between the expression of c-fos gene and the genes coding for proteins involved in phototransduction, in terms of their diurnal variation and in their development, suggested that c-fos gene may play a role in the regulation of these genes in retinal cells during the light/dark cycle. Copyright © 1996 Elsevier Science Ltd

Influence of Obstructive Sleep Apnea on Diastolic Heart Failure

Heart failure is frequently complicated by obstructive sleep apnea, which raises blood pressure and arrhythmiaand worsens prognosis. However, the incidence and influence of obstructive sleep apnea in patientswith diastolic heart failure is unknown. We hypothesized that patients with diastolic heart failurecomplicated by obstructive sleep apnea may have a worse outcome compared to those without obstructivesleep apnea. The study included 49 patients with an ejection fraction &#8805; 50 %, of whom 34 had diastolic heartfailure and 15 did not have diastolic heart failure. The patients were examined in a sleep study and byechocardiography. Brain natriuretic peptide (BNP) levels were determined at admission and 1, 6 and 12months thereafter. The prevalence of obstructive sleep apnea in patients with diastolic heart failure( 18/34,53 %) was significantly higher than that in those without diastolic heart failure (3/15, 20 %)(p=0.032).BNP levels were high at admission in patients with diastolic heart failure, but then decreased gradually inthose without obstructive sleep apnea. However, BNP in patients with diastolic heart failure and obstructivesleep apnea remained high and was significantly elevated compared to the level in patients without obstructivesleep apnea at 6 and 12 months after admission. Patients with diastolic heart failure and obstructivesleep apnea showed prolongation of elevated BNP, indicating that complication of diastolic heart failure byobstructive sleep apnea may aggravate cardiac function

Effects of Norepinephrine on Left Ventricular Hemodynamics and Myocardial Blood Flow in Rats with and without Calcium Overload

Heart failure patients have been shown to have an increased blood norepinephrine concentration, and patients with a high norepinephrine concentration have a poor prognosis. Norepinephrine is a catecholamine with α_1 and β_1 effects, which lead to a vasoconstrictive action and enhancement of myocardial contraction. However, the consequences of norepinephrine-induced changes in myocardial blood flow in heart failure patients remain unknown. In this study, the influence of norepinephrine on hemodynamics and blood flow in the left ventricular myocardium was investigated using rats with and without a calcium load. Norepineph-rine without a calcium load induced a 29.3% reduction of myocardial blood flow (MBF), but had no significant effect on ejection fraction (EF) and left ventricular end-diastolic pressure (LVEDP). With simultaneous calcium administration, norepinephrine induced a 33.2% reduction of MBF and increased LVEDP significantly, but caused no reduction in EF. These results suggest that norepinephrine decreases MBF but has no effects on systolic function, and increases LVEDP and decreases MBF more markedly in combination with calcium

A newly designed automatic pH-cycling system to simulate daily pH fluctuations.

The aim of this study was to develop and evaluate an automatic pH-cycling system, which was intended for performing time-lapse analyses of dental caries. Two single-section specimens prepared from each of the five extracted human incisors were studied under a condition of 3- or 9-cycles/day for seven weeks. Increase of mineral loss (delta delta Z) and increase of Ld (delta Ld) were examined and compared at the end of every week during the study. In the 3-cycles/day condition, delta delta Z and delta Ld significantly increased only at Week 7. In the 9-cycles/day condition, delta deltaZ increased significantly from Week 5. delta Ld increased from Week 2, and then there were no further increases for the subsequent five weeks. Based on the results of this study, progression pattern was found to be significantly different between the two conditions. We therefore concluded that the automatic pH-cycling system which we have developed qualified as a model system that simulated the human oral cavity. As such, it could be beneficially employed to clarify the roles of many factors that cause or prevent caries development in human teeth

Development of new software as a convenient analysis method for dental microradiography.

To the end of developing a convenient research tool to calculate the mineralization status of teeth in detail, a new program was developed using Visual Basic for Applications combined with Microsoft Excel 2004. To demonstrate the usefulness of this program, it was used to analyze tooth enamel mineralization after acid exposure. Transverse microradiography images (TMR) of specimens were digitalized with a charge-coupled device camera with a microscope (CCD camera) and a digital film scanner (FS). Subsequently, the mineral content profile of each specimen after de- and remineralization studies were calculated using the Angmar's formula. The newly developed program was applied to calculating the mineral loss (DeltaZ), lesion depth (Ld), surface zone depth (SZd), and lesion body depth (LBd) of tooth specimens. In addition, the outer surface zone (OSZ), inner lesion body (ILB), and sandwich area (SA) between OSZ and ILB- which together constituted DeltaZ - were calculated by the newly developed program. Data obtained with the newly developed program were in good agreement for both CCD camera and FS, indicating that the program was reliable for tooth enamel mineralization research studies

The effects of different application time on all-in-one self-etching adhesives

The purpose of this study was to evaluate the effects of different application times in all-in-one systems on micro-tensile bond strength. Three all-in-one systems, EB （Easy Bond, 3M ESPE, St. Paul, MN, USA）, BB （BeautiBond, Shofu Inc., Japan） and BF （BondForce, Tokuyama Denetal, Ibaraki, Japan）were used with four different application times: 10s, 20s, 30s, and 40s. Bond strengths to dentin were determined using μTBS test after 24h of water storage at 37℃. In addition, an evaluation of both resin-dentin interface, and fractured surface on dentin side was performed by SEM. The maximum μTBS for each system was observed with a 20s application time. There was no positive correlation between the thickness of hybrid layers and application time, which meant hybrid layers did not increase in thickness along with the increase in application time, rather a difference of quality was detected. Prolonged application time affected the adhesive strength of all-in-one systems, and they were mostly effective for the 20s application time