Epiretinal membrane removal in diabetic eyes: comparison of viscodissection with conventional methods of membrane peeling.

AIMS: To compare conventional methods of epiretinal membrane peeling with viscodissection. METHODS: 154 eyes with proliferative diabetic retinopathy (PDR) that underwent pars plana vitrectomy with membrane dissection (89 traditional, 65 viscodissection) were studied retrospectively. Incidence of retinal breaks (RBs), length of time under anaesthesia, postoperative intraocular pressure, retinal reattachment rate, and final visual acuity (VA) were measured. RESULTS: To compare cases of similar complexity, a "complexity score" was defined. The average complexity score for cases done with and without viscodissection was 4.7 and 3.2, respectively. The mean frequency of RBs in eyes undergoing viscodissection was 0.43 (SD 0.5) v 0.14 (0.35) RBs/eye without viscodissection. In complex cases, the frequency of posterior/peripheral RBs was 0.31 (0.47)/0.13 (0.34) RBs/eye, respectively, with viscodissection v 0.12 (0.33)/0.23 (0.43) RBs/eye without viscodissection. None of these differences were statistically significant. The average preoperative/postoperative VA (logMAR) in the viscodissection cohort was 1.7/1.3 (range 0.3 to >1.9/0.1 to >1.9) v 1.4/1 (range 0.48 to >1.9/0.1 to >1.9) in the non-viscodissection cohort, among eyes with 6 months of follow up. Anaesthesia duration was significantly shorter for cases done without viscodissection (p=0.03), but cases done with viscodissection were significantly more complex than cases done without viscodissection (p<0.0001). CONCLUSION: Viscodissection appears to be a safe and effective alternative technique in eyes with PDR. Owing to the retrospective nature of the study, additional studies are warranted.

Use of viscodissection and silicone oil in vitrectomy for severe diabetic retinopathy.

Improvement in surgical techniques has led to improved anatomic and functional success rates following surgery for severe complications of proliferative diabetic retinopathy (PDR). We compared the anatomic and functional outcomes of surgery in a non-randomized, consecutive case series of patients with severe PDR. We found that viscodissection using Healon provides outcomes comparable to conventional pick and scissors dissection. We also found that adjunctive use of silicone oil can salvage selected cases with particularly severe manifestations of PDR (e.g., the fibrinoid syndrome). With proper selection of patients and techniques, the anatomic success rate can exceed 80% even in the most severe cases. The goal of this paper is to show the applicability of using viscodissection and silicone oil infusion during vitrectomy in eyes with severe PDR.

Radiologic differentiation of intraocular glass: evaluation of imaging techniques, glass types, size, and effect of intraocular hemorrhage.

OBJECTIVE: The accurate detection of intraocular foreign bodies is critically important in treating ocular trauma. The purpose of this study was to evaluate the efficacy of CT, MR imaging, and sonography in detecting seven types of glass varying in size and placed in three locations in the globe, and to examine the effect of intraocular hemorrhage. MATERIALS AND METHODS: Glass pieces were cut into 1.5-, 1.0-, and 0.5-mm pieces and implanted on the corneal surface and the anterior and posterior chambers of 42 fresh porcine eyes. Twenty-one eyes were scanned comparing axial CT, helical CT, and MR imaging. The remaining 21 eyes were scanned using helical CT and sonography after implantation in a simulated human skull before and after placement of blood in the anterior chamber (hyphema). RESULTS: Detection rates were 57.1% for helical CT, 41.3% for axial CT, and 11.1% for T1-weighted MR imaging (n = 63 fragments). Results were significant (p < 0.0001). Sonography detected 43% of glass fragments in the posterior chamber and 24% in the anterior chamber. Detectability was greatest for green beer bottle glass (90.3%) and least for spectacle glass (43.1%) (p < 0.0001). Detection rates for size ranged from 96.2% at 1.5 mm to 48.3% at 0.5 mm, which was also significant (p < 0.0001). On helical CT, anterior chamber glass was easiest to detect (91.7%) and corneal surface glass the most difficult (64.9%). Hyphema made no statistical difference (p < 0.0001). CONCLUSION: Helical CT was the most sensitive imaging modality for the detection of intraocular glass. The sensitivity of detection was unaffected by hyphema but was determined by the type of glass, size, and location.

Effects of aging and estradiol supplementation on GH axis dynamics in women.

GH and IGF-I secretion decrease with age. The decline in serum GH with age appears to be associated with menopause. Prior studies of GH release before and after oral and transdermal hormonal replacement in the postmenopausal patient have shown no change or an increase in GH secretion. To distinguish the somatotropic axis effects of aging from those of estrogen deficiency, we compared eight prematurely menopausal women, aged 25-40 yr, with eight postmenopausal women, aged 51-70 yr, both before and after estradiol replacement. All women had a body mass index below 28 kg/m2. All were evaluated twice with frequent blood sampling every 10 min for 24 h. Studies were performed in the absence of exogenous hormones and 6-8 wk after transdermal estradiol replacement, targeted to achieve a serum estradiol level of 367 pmol/liter. GH pulsatility was analyzed. Variables tested included mean GH levels, interpulse baseline mean, pulse frequency per 24 h, and pulse amplitude. Transdermal estrogen replacement had a significant effect on mean GH levels and mean basal GH levels in both the premature ovarian failure and the age-appropriate postmenopausal group. No differences were noted in GH pulse frequency, GH pulse amplitude, IGF-I, IGF-binding protein-1, and IGF-binding protein-3 before and after treatment. A pronounced age effect was noted between the two groups. The premature ovarian failure women secreted significantly greater mean GH than the age-appropriate postmenopausal group regardless of treatment, with a significance level of P = 0.026. Interpulse baseline GH means were greater in the premature ovarian failure women than in the age-appropriate postmenopausal group, but the significance of this relationship was obliterated after adjustment for body mass index. Pulse amplitude was significantly increased in the premature ovarian failure women compared with age-appropriate postmenopausal women (P = 0.006). No significant changes were detected in the GH pulse frequency between the premature ovarian failure and postmenopausal groups. We conclude that moderate doses of transdermal estradiol supplementation do not exert a great effect on the somatotropic axis in women. Age and body composition appear to be the predominant influences on GH activity in women.

Changes in alveolar bone height and width following ridge augmentation using bone graft and membranes.

BACKGROUND: Clinical observation suggests the amount of bone height and width created during guided bone regeneration (GBR) to augment alveolar ridges is not retained during healing. A study was designed to determine: 1) whether the amount of osseous structure 4 months postoperatively after GBR was significantly less than the amount surgically created; and 2) if this change was uniform over the area treated. METHODS: Nineteen extraction sites (10 patients) were treated with GBR prior to placing endosseous implants. Allograft (DMFDB) and a bioabsorbable membrane were employed. Standardized measurements were taken of alveolar height and width 1) prior to augmentation; 2) after placement of graft and membrane; and 3) following 4 months of healing. Width measurements were taken 3 mm, 5 mm, and 10 mm from the crest at 3 intervals: the mesio-distal midpoint of the edentulous area and 3 mm mesial and distal to the midpoint. Height measurements were recorded at the mesio-distal midpoint and points 3 mm mesial and distal to the midpoint. RESULTS: Loss in width of supplemented bone after 4 months of healing ranged from 52.1% to 58.0% 3 mm from the crest, 47.6% to 67.4% 5 mm from the crest, and 39.1 % to 46.7% 10 mm from the crest. Loss of augmented height averaged 14. 7% in the center of the edentulous area but ranged from 60.5% to 76.3% 3 mm mesial and distal to the midpoint. CONCLUSIONS: The results indicate significant non-uniform loss of augmented alveolar height and width during GBR healing. The implications of these findings impact preoperative augmentation planning for endosseous implantology.

In vivo disruption of the fas pathway abrogates gastric growth alterations secondary to Helicobacter infection.

Helicobacter infection is associated with gastric cell growth alterations, plausibly predisposing to ulcer disease and gastric adenocarcinoma. Previous investigations from our laboratory have implicated the involvement of the Fas pathway in Helicobacter-induced apoptotic signaling in vitro. In this report we use C57BL/6J00064 mice to examine the direct role of Fas signaling in Helicobacter-mediated growth alterations in vivo. Helicobacter infection up-regulated gastric cell Fas antigen (Fas Ag) mRNA and increased surface receptor expression, along with concomitant altered apoptotic and proliferative response, measured by terminal deoxytransferase-deoxyuridine 5'-triphosphate nick end labeling and 5-bromo-2'-deoxuridine immunohistochemistry, respectively. In addition, histopathological alterations, including parietal cell loss and gastric atrophy, were noted. In contrast, infection in B6. MRL-FAS(lpr), a Fas Ag knockout mouse in the C57BL/6 background, did not result in increased apoptosis, proliferation, or histological alterations, a finding that argues strongly for the role of Fas-signaling pathway in orchestrating diverse growth responses to Helicobacter infection.

Non-Asian hepatocellular carcinoma: correlation between histologic features and echogenicity.

Studies of hepatocellular carcinoma in Asia have revealed a correlation between lesion hyperechogenicity and five histologic features: nonliquefied necrosis, sinusoidal dilatation, hemorrhage, fatty metamorphosis, and fibrosis. However, this correlation has not been investigated for non-Asian hepatocellular carcinoma, despite substantial differences between the Asian and non-Asian forms of this carcinoma. We retrospectively reviewed records of 29 patients seen at one United States institution who had hepatocellular carcinoma lesions that were either completely hyperechoic or completely hypoechoic. Tissue specimens obtained surgically (n = 7) or percutaneously (n = 22) were evaluated microscopically for the presence of nonliquefied necrosis, sinusoidal dilatation, hemorrhage, fatty metamorphosis, and fibrosis. A statistically significant correlation was identified between the number of histologic features identified and lesion diameter (P = 0.04) but not between the number of histologic features identified and the likelihood of hyperechogenicity (P = 0.11). Two lesions (50%) with three histologic features, four lesions (40%) with two histologic features, and six lesions (55%) with one histologic feature were hypoechoic. The echogenicity of non-Asian hepatocellular carcinoma lesions cannot be attributed to the histologic features that are believed to underlie echogenicity of the Asian type of hepatocellular carcinoma.

Microleakage of compomer class V restorations: effect of load cycling, thermal cycling, and cavity shape differences.

STATEMENT OF PROBLEM: Microleakage is an important problem with direct filling restorations and an understanding of the factors that contribute to it is of critical importance. PURPOSE: This study investigated the effect of thermal and occlusal load cycling, and limited cavity preparation on microleakage of compomer Class V restorations in vitro. MATERIAL AND METHODS: Class V cavities were randomly prepared on the buccal and lingual surfaces of 32 recently extracted molars and premolars and restored with Dyract compomer restorative system as per the manufacturer's directions. Teeth were randomly assigned to 1 of 4 treatment groups with 8 teeth in each group: (I) thermocycling only; (II) load cycling only; (III) both thermocycling and load cycling; and (IV) no treatment. All teeth were then immersed in 2% basic fuchsin solution for 24 hours. Dye penetration was measured linearly using color photographic prints. ANOVA, comparisons between means, and correlation were used to analyze the results. RESULTS: Thermocycling and cavity preparation had a significant effect on microleakage, but load cycling did not. Occlusal margins leaked more than the gingival margins. CONCLUSION: Class V restorations demonstrated increased microleakage under the conditions of thermal cycling and nonretentive cavity design. More microleakage occurred at occlusal margins than at gingival margins. The effect of load cycling is complicated by considerations of the types of stresses applied and the restorative material response to such stresses.

Urban anglers' perception of risk from contaminated fish.

The Newark Bay Complex includes the Newark Bay, tidal portions of the Hackensack River, Passaic River, Arthur Kill, and Kill van Kull. It is a highly industrialized urban area including five counties and more than 20 local governments with a large racially-mixed population of more than 3 million people. In 1982, research conducted by the New Jersey Department of Environmental Protection (NJDEP) showed elevated levels of chemical contaminants in five species of fish and one type of crab in the Newark Bay Complex. Subsequently, the State of New Jersey adopted advisories to guide citizens on safe consumption practices for fish and crabs. Since then, fish consumption advisories have been issued primarily through the Fish and Game Digest, a publication distributed by the state to licensed anglers. However, anglers in the Complex are not required to have a fishing license because the waters are marine. Therefore, most anglers in this area do not receive advisory information. To gain greater insight into the information sources and risk perceptions of urban anglers, a survey was conducted of 300 anglers at 26 fishing and crabbing locations in the Newark Bay Complex during the summer and early fall of 1995. The objectives of the study were to learn anglers': (1) knowledge of fish consumption advisories; (2) belief in the advisories; (3) perception of how safe fish are to eat; (4) sources for information about fish and fishing; and (5) sources for information on fish consumption advisories. The study concluded that while 60% had heard about advisories, they either did not believe or were unconcerned about health effects from eating contaminated species. In addition, the most used source for information about fish and fishing was other fishermen, while newspapers were selected as a source for information about community news, health, and food safety.

Fishing in urban New Jersey: ethnicity affects information sources, perception, and compliance.

Recreational and subsistence angling are important aspects of urban culture for much of North America where people are concentrated near the coasts or major rivers. Yet there are fish and shellfish advisories for many estuaries, rivers, and lakes, and these are not always heeded. This paper examines fishing behavior, sources of information, perceptions, and compliance with fishing advisories as a function of ethnicity for people fishing in the Newark Bay Complex of the New York-New Jersey Harbor. We test the null hypothesis that there were no ethnic differences in sources of information, perceptions of the safety of fish consumption, and compliance with advisories. There were ethnic differences in consumption rates, sources of information about fishing, knowledge about the safety of the fish, awareness of fishing advisories or of the correct advisories, and knowledge about risks for increased cancer and to unborn and young children. In general, the knowledge base was much lower for Hispanics, was intermediate for blacks, and was greatest for whites. When presented with a statement about the potential risks from eating fish, there were no differences in their willingness to stop eating fish or to encourage pregnant women to stop. These results indicate a willingness to comply with advisories regardless of ethnicity, but a vast difference in the base knowledge necessary to make informed risk decisions about the safety of fish and shellfish. Although the overall median income level of the population was in the $25,000-34,999 income category, for Hispanics it was on the border between $15,000-24,999 and $25,000-34,999.

Persistent pregnanediol glucuronide secretion after gonadotrophin suppression indicates adrenal source of progesterone in premature ovarian failure.

A 2-3 fold higher urinary pregnanediol glucuronide excretion has been observed in women with premature ovarian failure, compared with age-appropriate menopausal women. Progesterone, the precursor of urinary pregnanediol glucuronide, is a secretory product of either adrenal or ovarian origin. We postulated that suppression of pituitary gonadotrophin secretion by down-regulation with a long-acting gonadotrophin-releasing hormone agonist, leuprolide acetate, would decrease ovarian but not adrenal pregnanediol glucuronide. This would demonstrate a major difference in the ovarian hormonal milieu of these two groups of women. Four volunteers with premature ovarian failure collected daily first morning voided urine samples for 1 month prior to leuprolide acetate administration. Leuprolide acetate was then administered monthly for 3 months while continuing daily urinary collection. Luteinizing hormone (LH), follicle stimulating hormone (FSH), and pregnanediol glucuronide were measured in all samples and normalized for creatinine. Comparisons of pre- and post-median values for luteinizing hormone (LH), FSH, and pregnanediol glucuronide were made using the Wilcoxon rank sum test. This demonstrated significant suppression of both LH and FSH. Pregnanediol glucuronide, however, did not demonstrate a significant decline, strongly implying an adrenal source of the enhanced excretion. The decreased pregnanediol glucuronide noted in age-appropriate menopausal women compared with premature ovarian failure is likely to be a reflection of adrenal ageing.

Elevated maternal serum relaxin concentrations throughout pregnancy in singleton gestations after superovulation.

OBJECTIVE: To test the hypothesis that superovulation results in elevated maternal circulating relaxin concentrations throughout the second and third trimesters of pregnancy, independent of the pattern of hCG secretion. METHODS: Two groups of women with singleton gestations were studied: a group of nine women who achieved pregnancy after stimulation with human menopausal gonadotropin and a group of six women who achieved pregnancy without prior stimulation. Peripheral blood samples were drawn approximately every 5 weeks throughout the second and third trimesters. Serum relaxin concentrations were measured using a human relaxin-specific enzyme-linked immunosorbent assay; hCG was measured by an immunofluorometric assay. RESULTS: The stimulated group had significantly higher relaxin levels throughout pregnancy (P=.007, multivariate analysis of variance) than did nonstimulated controls. The mean relaxin level in stimulated patients was 1.78 ng/mL (95% confidence interval [CI] 1.5, 2.17) and in nonstimulated subjects the level was 0.73 ng/mL (95% CI 0.59, 1.25). Spline fits demonstrated that stimulated patients had higher relaxin levels throughout the second and third trimesters. There was no significant difference in hCG concentrations between the two groups (P=.61). CONCLUSION: In singleton gestations after superovulation, maternal serum relaxin concentrations are significantly higher throughout the second and third trimesters of pregnancy. These differences are independent of the pattern of hCG secretion. It appears that luteal relaxin secretion is controlled by factors in addition to hCG.

Early induction of mRNA for calbindin-D28k and BDNF but not NT-3 in rat hippocampus after kainic acid treatment.

The influence of kainic acid (KA), which induces acute seizures, on expression of mRNA for the calcium-binding protein, calbindin-D28k, brain-derived neurotrophic factor (BDNF), neurotrophin-3 (NT-3) and early-response genes [c-fos, zif268 (NGFI-A), nur77 (NGFI-B)] was examined in rat hippocampus by Northern blot analysis. A significant increase (3.2-fold) in BDNF mRNA was observed 1 h after KA injection (12 mg/kg i.p.) and peak expression (9.4-fold) occurred 3 h after KA. The induction of BDNF mRNA was preceded by the induction of c-fos, mRNA (30 min after KA) and was followed by the induction of calbindin-D28k mRNA (3.5-fold 3 h after KA; a maximal response was at 3-6 h after KA). Region-specific changes, analyzed by immunocytochemistry and in situ hybridization, indicated that the most dramatic increases in calbindin protein and mRNA after KA treatment were in the dentate gyrus. Although calbindin-D28k and BDNF mRNAs were induced, a 3.4-3.8-fold decrease in NT-3 mRNA was observed by Northern analysis 3-24 h after KA treatment. Calbindin-D28k gene expression was also examined in rats with a chronic epileptic state characterized by recurrent seizures established with an episode of electrical stimulation-induced status epilepticus (SE). When these animals were examined 30 days post-SE, no changes in hippocampal calbindin-D28k mRNA were observed. Our findings suggest that the induction of calbindin-D28k mRNA (which may be interrelated to the induction of BDNF mRNA) is an early response which may not be related to enhanced neuronal activity or seizures per se, but rather to maintaining neuronal viability.

Androgen modulation of the messenger ribonucleic acid of retinoic acid receptors in the prostate, seminal vesicles, and kidney in the rat.

Previously, we reported that the steady state level of messenger RNA (mRNA) transcripts of retinoic acid receptors (RAR) alpha and gamma in the testes of 20-day-old rats can be modulated by exogenous testosterone. These results suggest that androgen regulation of Sertoli cell functions may involve biochemical events mediated by RAR genes. In this study, we examined the effects of castration and testosterone replacement on the steady state level of mRNA transcripts for RAR alpha and gamma in the prostate, seminal vesicles, and kidney of the rat. Northern blot analysis revealed that in intact adult rats, the relative steady state levels of the 3.4- and 2.7-kilobase (kb) mRNA transcripts for RAR alpha and the 3.4-kb transcript for RAR gamma in the prostate were at least 20-fold higher than those in the seminal vesicles and kidney. The relatively high abundance of RAR mRNA transcripts in the prostate suggests the physiological importance of RAR-mediated processes in this organ. Castration resulted in an increase in the level of RAR mRNA transcripts in the prostate and seminal vesicles, reaching a maximum of 2- to 4-fold in the prostate and 15- to 23-fold in the seminal vesicles within 6 days. On the other hand, the levels of mRNA transcripts of RAR alpha and -gamma in the kidney were reduced by 40-50% 1 day after castration. The effects of castration on RAR mRNA levels in all three organs were prevented by implantation of 3-cm testosterone capsules at the time of castration, a regimen that provides physiological levels of serum testosterone. In a subsequent experiment, adult male rats were given a single sc injection of 2 mg testosterone 3 days after castration. This treatment resulted in an acute suppression of the level of RAR mRNA transcripts in all three organs within 30 min. Thereafter, the levels of RAR alpha and -gamma mRNA transcripts in the prostate continued to decrease, whereas those in the seminal vesicles returned to the castrated levels within 6 h. On the other hand, RAR mRNA levels in the kidney rebounded by 1 h and remained at the level found in the untreated castrated rats. These results demonstrate that the steady state level of mRNA transcripts for RAR alpha and -gamma in the prostate, seminal vesicles, and kidney can be modulated by testosterone in organ-specific manners, thus suggesting that the RAR-mediated processes may be involved in the effects of androgen in these organs. Furthermore, the relatively low increment in prostatic RAR mRNA levels after castration compared to that in the seminal vesicles demonstrates a difference in androgen responses between these two organs. This difference could dictate the efficacy of the effects of androgen on cellular function and may contribute to the disparate vulnerabilities to androgen-related uncontrolled cell proliferation and/or malignancy in the prostate and seminal vesicles.

Morphometric study of the placental vessels and its correlation with umbilical artery Doppler flow.

OBJECTIVE: To determine the changes in the vessel-wall thickness and the radius of the lumen in tertiary-stem villi of the placenta with advancing gestational duration and their relationship to umbilical artery Doppler flow studies. METHODS: Placentas from 63 miscarriages and preterm and term deliveries (between 19 and 40 weeks) were used for morphometric study of the tertiary-stem villi vessels. Each woman had undergone Doppler flow study of the umbilical artery. The resistance index (RI) was determined from the Doppler flow velocity waveform. Placental paraffin sections of 4-micron thickness were stained with hematoxylin and eosin and with periodic acid-Schiff reagents. The tertiary-stem villi and their vessels were examined microscopically and assessed morphometrically using a personal computer with math co-processor and a touch-sensitive screen overlying a video monitor. The monitor received microscopic images from a video camera that was mounted on a microscope. We determined vessel-wall thickness by tracing the outer and inner circumferences of digitized vessel-wall images. RESULTS: Wall thickness, but not lumen size, of the tertiary-stem villi vessels decreased significantly overall at a rate of 0.63micron/week (P < .001). The rate of decrease was 0.64micron/week (P < .001) during the second trimester and 0.50micron/week (P < .001) during the third trimester. There was a significant correlation between the decrease in thickness and in RI (r = 0.83 [P < .001], r = 0.78 [P < .001] in the second and third trimesters, respectively). Resistance indices were all within normal limits. CONCLUSIONS: Placental tertiary-stem villi vessel-wall thickness decreases with advancing gestational age. There is a correlation between the changes in RI of the umbilical artery Doppler flow and the changes in mean wall thickness of the placental vessels.

Lessons learned from autopsies at a pediatric teaching hospital.

Twenty-six percent of pediatric patients had discrepant major diagnoses revealed at autopsy. A printed form used to document permission for autopsies improved the autopsy rate. No variables were found to predict the success rate for obtaining autopsies.

Benefits of continuous physiological pulsatile gonadotropin-releasing hormone therapy in women with polycystic ovarian syndrome.

OBJECTIVE: Can continuous pulsatile GnRH from one ovulatory cycle to another enhance the endocrine milieu of women with polycystic ovarian syndrome (PCOS)? DESIGN: Five women with well-characterized, clomiphene citrate (CC)- and hMG-resistant PCOS were treated with a 100 ng/kg per bolus of IV pulsatile GnRH (Lutrepulse; Ortho Pharmaceutical Corporation, Raritan, NJ) every 90 minutes for two consecutive ovulatory cycles. Weekly vaginal ultrasonography and daily blood sampling for LH (mIU/mL), FSH (mIU/mL), E2 (pg/mL), and P (ng/mL) were performed. These data were compared with a control group of normally cycling women. RESULTS: First ovulatory cycles on therapy were characterized by significantly increased mean follicular phase LH = 88 (arbitrary units area under the curve [AUC]) compared with second cycles (28 mean AUC units) and controls (13 mean AUC units). Luteal phase E2 (3,081 mean AUC units) was significantly increased in first cycles compared with second cycles (880 mean AUC units) and controls (1,562 mean AUC units in PCOS). Luteal phase E2 secretion was elevated in second cycles when compared with normal but not significantly. The changes occurring between the first and second ovulatory cycles in women with PCOS resulted in a more physiological overall pattern of gonadotropin and sex steroid secretion in the second cycles. Two singleton pregnancies were achieved in the second cycle. CONCLUSIONS: Low-dose pulsatile IV GnRH can successfully induce ovulation in women with PCOS who have failed to conceive on all previous conventional therapy (CC, hMG, and/or GnRH agonist, and hMG). Continuous cycle-to-cycle physiological GnRH replacement normalized the endocrine parameters of second cycles. Women with PCOS, even when ovulatory on pulsatile GnRH, do not display entirely normal gonadotropin and sex steroid dynamics.

Low-fusing counterdies for measuring accuracy of dies or impression materials.

Described in this pilot study is the genesis, development, and use of a system for measuring impression and die material accuracy with low-fusing bismuth alloy counterdies. The method followed the same sequence used in dental laboratory technology with the assumption that the errors associated with the wax pattern, investing, and casting had been largely eliminated. Determination of the alloy shrinkage was the first step, followed by a comparison of two impression and two die materials used in conjunction with master dies of full crown and MOD configurations. Misfit measurements revealed marginal openings of 12 to 219 microns depending on die configuration, the impression, or the die material. A 2 x 2 factorial statistical model with interaction revealed main and interactive effects. This procedure could be useful in future investigations.

Elevated first-trimester serum relaxin concentrations in pregnant women following ovarian stimulation predict prematurity risk and preterm delivery.

OBJECTIVE: To determine whether ovarian stimulation would result in higher circulating relaxin concentrations and whether this hyperrelaxinemia would be associated with prematurity. METHODS: Two groups of women were studied: 1) women achieving pregnancy after ovarian stimulation (n = 114) and 2) women achieving pregnancy without treatment (n = 37). Serum was obtained at 6-12 weeks' gestational age; fetal number was determined by transvaginal ultrasound. Prematurity risk or preterm delivery was determined from the obstetric record. A specific human relaxin enzyme-linked immunosorbent assay was used to measure serum relaxin concentrations. Hyperrelaxinemia was defined as levels greater than 3 standard deviations above the weighted mean of levels in normal unstimulated singleton pregnancies at 6-12 weeks' gestation. RESULTS: An association was found between prematurity risk or premature delivery and peripheral relaxin concentrations during weeks 6-12 of pregnancy in women having ovarian stimulation and in women having multiple gestations. Circulating relaxin concentrations greater than 16 ng/mL in women having ovarian stimulation and levels greater than 7 ng/mL in women who had multiple gestations predicted prematurity risk or premature delivery in 50% of the women. CONCLUSIONS: These data demonstrate that after ovarian stimulation, some women have highly elevated circulating first-trimester relaxin concentrations. First-trimester hyperrelaxinemia identifies a group of women at risk for prematurity who can be monitored aggressively.

Preovulatory follicle number predicts corpora lutea number in early pregnancy.

A moderately strong correlation was coefficient was obtained between the relationship of mature follicle number versus CL number by use of vaginal US. This suggests an accurate prediction of CL number, especially between 1 and 4 mature follicle number as determined by the LOWESS curve.