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The objective of this study was to evaluate the effect of pregnancy, breed, and hair coat on body temperature and sweating rate (SR) of hair sheep. St. Croix White (STX; n= 9) and Dorper × STX (DRPX; n= 9) ewes (3.6 yr of age) were evaluated over 4 d at 126 d of gestation (PREG) and over 4 d at 46 d postpartum (OPEN) in the shade and sun and in the morning (AM; 0900 to 1200 h) and afternoon (PM; 1300 to 1600 h) after a 20 min acclimation to each condition on each day. Data loggers recorded vaginal temperature (VT) at 10-min intervals for 96 h. Rectal temperature (RT) was measured using a digital veterinary thermometer, and respiration rate (RR) was measured as breaths per minute (bpm). Sweating rate was calculated from measured air properties passing over a shaved (300 cm2) and unshaved area of the ewes' body using a portable calorimeter. Data were analyzed using GLM procedures of SAS (SAS Inst. Inc., Cary, NC) with breed, pregnancy status, sun exposure, and time of day as main effects. Mean temperature, relative humidity, temperature-humidity index, wind speed, and solar radiation on the days of data collection were 28.2°C, 82.8%, 80.3, 4.2 km/h, and 237.5 W/m2, respectively. There was no difference (P> 0.10) in RT, RR, and SR between DRPX and STX ewes. The PREG ewes had lower RT (P< 0.007) and SR (P< 0.0001) and higher RR (P< 0.007) than OPEN ewes (38.5 ± 0.2 vs. 39.1 ± 0.2°C, 70.2 ± 3.1 vs. 88.3 ± 3.1 g⋅m−2⋅h−1, and 79.5 ± 2.2 vs. 72.1 ± 2.2 bpm, respectively). During the PM, RR, RT (P< 0.05), and SR (P< 0.006) were higher than in the AM. In the sun, RR (P< 0.001) and SR (P< 0.0001) were higher than in the shade, but there was no difference (P> 0.10) in RT. There was no difference in SR (P> 0.10) between the shaved and unshaved area of the ewe. The DRPX ewes had higher (P< 0.0001) VT than STX ewes. The PREG ewes had higher (P< 0.001) VT than OPEN ewes during the night time and lower VT than the OPEN ewes during the day time (P< 0.0001). The OPEN ewes had a greater (P< 0.009) daily range of VT than PREG ewes did (2.5 ± 0.4 vs. 1.1 ± 0.4°C, respectively), but there was no breed difference (P> 0.10). Hair coat did not have an influence on the SR of the ewes, and PREG ewes appeared to use increased respiration as opposed to sweating to help control RT. The narrower range of body temperature, measured as VT, of PREG compared to OPEN ewes may be a protective mechanism for the developing fetus.

To compare early second-trimester maternal serum placenta growth factor concentrations in Down syndrome pregnancies and those in normal pregnancies. A case–control study was performed to evaluate the maternal serum placenta growth factor concentrations in 36 Down syndrome and 320 normal pregnancies with matched gestational age during the second trimester. For the detection of serum concentrations of placenta growth factor, a quantitative sandwich enzyme immunoassay technique (R & D Systems Inc., Minneapolis, Minnesota, USA) was performed. Using a multiple linear regression model, maternal serum placenta growth factor level was associated with gestational age (p&lt;0.001) and the existence of Down syndrome pregnancy (p&lt;0.001). After converting maternal serum placenta growth factor concentrations of each analyte to multiples of the appropriate gestational median (MoM), placenta growth factor MoM (p&lt;0.001) was revealed to be an independent variable for Down syndrome pregnancies after adjusting for the effects of maternal age (p&lt;0.001), free β-hCG (p&lt;0.001) and AFP (p=0.014) by multivariate logistic regression analysis. Maternal serum placenta growth factor concentration was elevated in Down syndrome pregnancies during the early second trimester. Placenta growth factor might be a novel marker for maternal serum Down syndrome screening. Copyright © 2002 John Wiley & Sons, Ltd.

Glycosaminoglycans (GAG) promote acrosome reactions (AR) in bovine and rabbit spermatozoa in vitro. Female bovine reproductive tract secretions contained GAG and the concentrations and composition of those GAG varied with different regions and stages of the estrous cycle. This study was designed to evaluate the types of GAG found in reproductive tract secretions of ewes at different stages of the estrous cycle and the ability of the secretions to promote AR. Ewes (n=48) were slaughtered at 0, 12, 24, 36,72 and 144 h following observations of standing estrus. Reproductive tracts were flushed with a modified Tyrode's medium (TALP; 7 ml) not containing calcium. Concentrations and composition of GAG in the tract were determined by high performance liquid chromatography. Concentrations of GAG decreased anterior to the cervix: 2.28 to .74 mg/100 mg protein (P<.05). Increases in heparin-like GAG during the estrual phase and chondroitin sulfate GAG during the luteal phase were noted. Bovine sperm were incubated in tract flushings standardized to contain 4 µg/ml of GAG and supplemented with calcium. Sperm incubated in estrual flushings for 9 h exhibited a higher incidence of AR than those incubated in luteal flushings or control, 50% vs 36% and 29%, respectively (P<.0001). It is concluded that during the estrous cycle there were changes in concentrations and composition of GAG in ewe reproductive tracts and the potencies of those female secretions causing AR varied.

Hepatolithiasis is a major disease in Asia but differences in operative incidence between countries have not been examined. A retrospective study was conducted in Taiwan, Hong Kong, and Singapore, and the results were compared with those in Japan with the aim of defining factors involved in the etiology of the condition. In order to ensure uniformity of the data collected, the same form was used throughout the study and was completed by the same personnel after reviewing the patient's record and radiographs in each case. The years 1976–1980 were chosen for the study, since the newer methods of diagnosis such as ultrasound, endoscopic retrograde cholangiography, and percutaneous transhepatic cholangiography became available during that period. The most significant finding was the difference in the relative prevalence of hepatolithiasis as a proportion of all gallstone cases in Taiwan, Hong Kong, and Singapore, where the majority of the population consisted of patients of Chinese descent. The highest prevalence, 53.5%, was found in Taiwan, while in Hong Kong it was 3.1% and in Singapore 1.7%. Environmental rather than ethnic factors are implicated in the cause of hepatolithiasis.

Concentrations of progesterone in uterine and arterial tissue and in uterine and jugular venous plasma were determined. Blood was collected on Days 4 and 9 postestrus from the jugular vein and the first and last venous branches draining each uterine cornu; uterine tissue and arteries were subsequently collected. Progesterone was greater (p<0.05) in the cranial third than in the middle or caudal thirds of the uterine horn adjacent to the corpus luteum (CL)-bearing ovary or in any third of the contralateral horn. Progesterone in uterine arterial segments adjacent to the CL-bearing ovary was higher (p<0.05) than in contralateral segments. Progesterone was higher (p<0.05) in blood from the first venous branch of the cranial third of the uterine cornu adjacent to the ovary with the CL, than in the last branch of the caudal third, or contralateral horn, or in jugular blood. When oviductal veins were resected on Day 9 postestrus, progesterone in the first vein draining the cranial third of the uterine cornu adjacent to the CL-containing ovary was not different (p>0.05) 48 h after resection than in the same vessel in the opposite horn or in jugular blood. We concluded that progesterone and other ovarian products may be delivered to the uterus locally.

The haemodynamic effects of ketanserin were studied consecutively in seventeen patients in the intensive care unit following coronary artery bypass grafting. Hypertensive patients (Group 1, systolic blood pressure (SBP) ≥ 150 mmHg following discontinuation of nitroprusside, n = 10) received intravenous ketanserin 10 mg and infusion of 0.1 mg.kg−1.hr−1with additional boluses as required to maintain SBP ≤ 130 mmHg for one hour. Non-hypertensive patients (Group 2, SBP < 150 mmHg, n = 7) received a 5 mg bolus and the same infusion. Ketanserin significantly decreased arterial blood pressure (P < 0.001) in all patients in Group 1. Heart rate was decreased but not significantly. Cardiac index, systemic and pulmonary vascular resistance and pulmonary shunt fraction were not significantly altered from pre-ketanserin values when blood pressure was controlled with nitroprusside. Normotensive patients in Group 2 did not show any undesirable hypotension or significant haemodynamic changes. Mean nitroprusside dose requirements following ketanserin therapy were significantly reduced by 91.6% in Group 1 and 78.4% in Group 2 (P < 0.05). Ketanserin is effective in treating hypertension following coronary artery bypass grafting with an advantage of lack of reflex tachycardia.

Our previous work confirmed the excellent activity of CuO−MoO3/Al2O3 for the destructive oxidation of (CH3)2S2. This study further investigates the effect of acid treatment on the performance of this catalyst. Four different kinds of inorganic acids (HCl, H2SO4, HNO3, H3PO4) are used to treat the γ-Al2O3 support before impregnating it with copper and molybdenum metal salts. The prepared catalysts are then used for the destructive oxidation of (CH3)2S2. Experimental results indicate that HCl-treated and H2SO4-treated catalysts exhibit a higher activity than those without acid treatment. In addition, the H2SO4-treated catalyst (CuO−MoO3/Al2O3−SO4^2-) displays the best stability. As BET surface area analysis demonstrates, the surface area and average pore diameter of the H2SO4-treated catalysts are larger than those without treatment; however, the increase in surface area is not the main factor in promoting the activity. XRD analysis reveals that the CuO−MoO3/Al2O3−SO4^2- catalyst also has the crystalline structure of Cu3Mo2O9 and CuMoO4 which have been found in CuO−MoO3/Al2O3 and which might play a prominent role in the catalyst activity. XPS and TGA analyses suggest that it might have the functional group of SO4^2- which exists on the surface of the CuO−MoO3/Al2O3−SO4^2- catalyst. The NH3-TPD pattern shows that the acidity is remarkably enhanced when the catalyst is treated with an H2SO4 solution. We believe that the substantial increase in activity is attributed primarily to the presence of the SO4^2- group and the formation of a copper molybdenum oxide phase on the catalyst surface.

Early weaning of calves from anestrous cows results in formation of short-lived corpora lutea (CL) unless the animals are pretreated with a progestagen (norgestomet). This study was conducted to investigate the relationship between pre- and post-ovulatory gonadotropin secretion and luteal lifespan. Postpartum beef cows were assigned randomly into two groups, control (n = 5) and norgestomet (implant given at weaning for 9 d; n = 7). Calves from all cows were weaned 30 to 33 d postpartum. Coccygeal artery cannulas were placed into cows in the control group 1 d prior to weaning and 2 d before implant removal in cows in the norgestomet group. Plasma for determination of luteinizing hormone (LH), follicle stimulating hormone (FSH), estradiol-17β (E) and progesterone (P) was collected daily at 10-min intervals for 6 h from weaning (control) or the day prior to implant removal (norgestomet) to estrus (d 0) and on d 2, 4 and 6 following estrus. Average interval (x̄ ± SE; P<.05) from weaning to estrus or implant removal was 4.2 ± .8 and 2.3 ± .2 d for the control and norgestomet groups, respectively. Estrous cycle length for the control group was 12.4 ± 1.8 d compared with 20.4 ± .3 d for the norgestomet group (P<.05). Four of five control cows had an estrous cycle length of 7 to 14 d; all cows in the norgestomet group and the remaining control cow had an estrous cycle of normal length (16 to 21 d). Mean concentrations and frequency, amplitude and duration of pulses of LH and FSH were not different between cows having short estrous cycles (control) and cows having a normal estrous cycle (norgestomet implant) 1, 2 or 3 d prior to first estrus and on d 2, 4 and 6 following first estrus. Concentrations of E were higher (P<.05) the day of estrus for the norgestomet group (9.9 ± 2.2 pg/ml) than for the control group (5.7 ± .8 pg/ml). We conclude that subnormal luteal function does not appear to be due to inadequate gonadotropic stimulation during either the pre- or post-ovulatory period.

The N-terminal region of the envelope (env) transmembrane protein of human immunodeficiency virus type 1 (HIV-1) has a leucine zipper-like motif. This highly conserved zipper motif, which consists of a heptad repeat of leucine or isoleucine residues, has been suggested to play a role in HIV-1 env glycoprotein oligomerization. This hypothesis was tested by replacing the highly conserved leucine or isoleucine residues in the zipper motif with a strong alpha-helix breaker, proline. We report here that such substitutions did not abolish the ability of env protein to form oligomers, indicating that this highly conserved zipper motif does not have a crucial role in env protein oligomerization. However, the mutant viruses all showed impaired infectivity, suggesting that this conserved zipper motif can have an important role in the virus life cycle.

An experimental investigation was conducted in steady flow to examine the fluid dynamics performance of three prosthetic heart valves of 27 mm diameter: Starr-Edwards caged ball valve, Bjork-Shiley convexo-concave tilting disk valve, and St. Vincent tilting disk valve. It was found that the pressure loss across the St. Vincent valve is the least and is, in general, about 70 percent of that of the Starr-Edwards valve. The pressure recovery is completed about 4 diameters downstream. The velocity profiles for the ball valve reveal a large single reversed flow region behind the occluder while those for the tilting disks valves reveal two reversed flow regions immediately behind the occluders. Small regions of stasis are also found near the wall in the minor opening of Bjork-Shiley valve and in the major opening of St. Vincent valve. The maximum wall shear stresses of the three valves at a flow rate of 30 l/min are in the range 30–50 dyn/cm2 which can cause hemolysis of attached red blood cells. The corresponding maximum Reynolds normal stresses are in the range of 1600–3100 dyn/cm2. The Reynolds normal stresses decay quickly and return approximately to the upstream undisturbed level at about 4 diameters downstream while the wall shear stresses decay at a slower rate. The maximum Reynolds normal stresses occur at about 1 diameter downstream while the maximum wall shear stress is at about 2 diameters downstream. In general, the St. Vincent valve has better performance. A method to compensate for refractive index variations and curvature effect of the sinus region of the aorta root using laser doppler anemometer measurements is also proposed.

An experimental investigation was conducted in steady flow to examine the fluid dynamics performance of three prosthetic heart valves of 27 mm diameter: Starr-Edwards caged ball valve, Bjork-Shiley convexo-concave tilting disk valve, and St. Vincent tilting disk valve. It was found that the pressure loss across the St. Vincent valve is the least and is, in general, about 70 percent of that of the Starr-Edwards valve. The pressure recovery is completed about 4 diameters downstream. The velocity profiles for the ball valve reveal a large single reversed flow region behind the occluder while those for the tilting disks valves reveal two reversed flow regions immediately behind the occluders. Small regions of stasis are also found near the wall in the minor opening of Bjork-Shiley valve and in the major opening of St. Vincent valve. The maximum wall shear stresses of the three valves at a flow rate of 30 l/min are in the range 30–50 dyn/cm2 which can cause hemolysis of attached red blood cells. The corresponding maximum Reynolds normal stresses are in the range of 1600–3100 dyn/cm2. The Reynolds normal stresses decay quickly and return approximately to the upstream undisturbed level at about 4 diameters downstream while the wall shear stresses decay at a slower rate. The maximum Reynolds normal stresses occur at about 1 diameter downstream while the maximum wall shear stress is at about 2 diameters downstream. In general, the St. Vincent valve has better performance. A method to compensate for refractive index variations and curvature effect of the sinus region of the aorta root using laser doppler anemometer measurements is also proposed.

The mainstay for prenatal diagnosis of fetuses with abnormal ultrasound is karyotyping. Array comparative genomic hybridization (CGH) has been used as an adjunct to conventional karyotyping for detection of chromosomal anomalies beyond the standard aneuploidy. Previous studies have reported that the detection rate with array CGH for submicroscopic chromosomal abnormalities is highly variable, ranging from 1.3 to 16. One major concern for the use of microarray CGH is that of uninterpretable copy number variations (CNVs), which will lead to parental anxiety and potentially unnecessary pregnancy terminations. Prospective data from a large cohort of fetuses who have undergone both karyotyping and CGH analysis are needed to demonstrate the diagnostic benefits of chromosomal array for prenatal identification of chromosomal abnormalities.

Background. The transient effects of epidural bupivacaine 0.25–0.5% on the Doppler velocimetry of umbilical and uterine arteries had been reported, but the effects of continuous lower dose epidural bupivacaine (0.05–0.1%) infusion for labour analgesia have never been reported. In this study, we evaluated the effects of continuous epidural bupivacaine 0.075% on the Doppler velocimetry of uterine arteries. Methods. Twenty pregnant women for labour analgesia received continuous epidural bupivacaine 0.075% infusion. We used a 4-MHz continuous-wave Doppler probe (Multigon 500A) with a 200 Hz thump filter to detect uterine blood flow velocity. We recorded the velocimetry data for uterine relaxation and contraction during five time periods: pre-epidural insertion, 1, 2, and 4 h post-epidural infusion, and after delivery of fetus. Results. Our data showed that the velocimetric indices of uterine vascular resistance were significantly increased 1, 2, and 4 h after epidural infusion when compared with the pre-epidural level; these returned to the baseline after delivery. Conclusion. Continuous epidural analgesia with bupivacaine 0.075% increases the resistance of uterine artery and therefore possibly reduces the uterine blood flow.