Spontaneous preterm birth as a function of normal cervical length in low-risk women.

OBJECTIVES: To identify if there is an increased risk for spontaneous preterm birth (sPTB) across the continuum of measured, normal cervical lengths (CL) in low-risk women. METHODS: Retrospective cohort study of women with singleton pregnancies and no history of prior sPTB. Women were included if they underwent mid-trimester transvaginal CL measurement between February 2016 and August 2018 and had a measured, normal CL ≥25mm. Women were excluded for progesterone exposure, fetal anomalies, or an unmeasurable CL due to a poorly developed lower uterine segment. The primary study outcome was sPTB <37 weeks. Secondary outcomes included: sPTB <35 weeks, birth gestational age (GA), and the number of hospital evaluations for suspected preterm labor (PTL). Cervical length was considered in interval groups 25-29mm, 30-34mm, 35-39mm, 40-44mm, and ≥45mm. Outcomes were analyzed with χ2 test of trend and as a continuum (linear models, logistic regression and ROC curve), where appropriate. RESULTS: 985 women were included. The incidence of sPTB <37 weeks was 3.7%, with a mean birth GA of 38.7 ± 2.4 weeks. The odds of sPTB <37 weeks decreased with increasing cervical length, considered in 5 mm intervals (odds ratio = 0.67; 95% confidence interval 0.49-0.90) and an increasing birth GA of 1 additional day for each CL increase of 3mm (p = .0002). Conversely, sPTB <35 weeks (p = .49) and mean hospital evaluations for PTL (p = .26) were similar across groups. The ROC curve area-under-the-curve for sPTB <37 weeks of 0.64 showed poor predictive value. CONCLUSIONS: Among women without a history of sPTB, there was an association of decreased risk of sPTB <37 weeks and advanced delivery GA with increasing, but normal-range CL measurements. However, the association was poor and was not associated with spontaneous preterm birth <35 weeks, or the number of hospital evaluations for PTL.

Contemporary Test Performance of the Random Urine Protein-to-creatinine Ratio.

OBJECTIVE: The random urine protein-to-creatinine ratio (UPCR) is a screening test used for predicting clinically significant proteinuria (urine protein ≥ 300 mg) during pregnancy. No consensus exists on the optimal random UPCR cutoff for performing follow-up 24 hour urine (24H) total protein collection. We aim to evaluate the test performance of random UPCR in predicting proteinuria in a contemporary cohort. STUDY DESIGN: This was a retrospective cohort study of pregnant patients at our institution from 2014 to 2018 with a random UPCR and follow-up 24H protein collection. The primary analysis estimated the test characteristics (sensitivity, specificity, positive and negative predictive values) of using random UPCR for the detection of proteinuria defined as urine protein ≥300 mg on 24H protein collection. UPCR cutoffs from 0.10 to 0.30 mg/dL were evaluated, receiver operator characteristic (ROC) curve was constructed, and area under the curve (AUC) was determined. A secondary analysis examined the correlation between UPCR and 24H protein using least squares regression and Pearson correlation. RESULTS: Paired UPCR and 24H collection results were available for 1,120 patients. Mean gestational age at time of UPCR was 31.1 ± 5.1 weeks and 687 (61.3%) of patients had a 24H ≥300 mg. UPCR <0.10 mg/dL effectively excluded proteinuria ≥300 mg on 24H collection, while UPCR ≥0.18 mg/dL correctly classifies proteinuria with 91% sensitivity, 57% specificity, 77% positive predictive value, and 79% negative predictive value. UPCR ≥1.07 mg/dL had 100% specificity for 24 hour proteinuria. The area under ROC curve was 0.86. UPCR and 24H collection were highly correlated with a Pearson correlation coefficient of 0.85. After our institution lowered the threshold to obtain a 24H from UPCR ≥0.20 mg/dL to ≥0.10 mg/dL in May 2017, the percentage of patients meeting criteria for 24H collection increased from 57.8 to 84.4%. CONCLUSION: The AUC and Pearson correlation suggest random UPCR is a high performance test for the prediction of proteinuria on 24H. Optimal test performance is dependent upon clinical consideration and upon the implications of the disease or condition. A random UPCR screen positive threshold of 0.18 mg/dL maximizes sensitivity to identify clinically significant proteinuria. KEY POINTS: · Random urine protein to creatinine ratio is a high performance test for proteinuria.. · A random UPCR threshold of 0.18 mg/dL maximizes sensitivity to identify proteinuria.. · Optimal test performance is dependent on the disease or clinical condition..

Quantifying the additional maternal morbidity in women with preeclampsia with severe features in whom immediate delivery is recommended.

BACKGROUND: Preeclampsia with severe features when diagnosed at less than 34 weeks is associated with maternal morbidity and is managed by immediate delivery or inpatient expectant management. OBJECTIVE: This study aimed to compare maternal morbidity in women with preeclampsia with severe features in whom the American College of Obstetricians and Gynecologists recommends immediate delivery versus those eligible for expectant management. STUDY DESIGN: This was a retrospective cohort study of women with preeclampsia with severe features delivered between 23 to 34 weeks of gestation from 2013 to 2017 at a single tertiary center. Women were categorized into 2 groups: (1) those recommended by the American College of Obstetricians and Gynecologists for immediate delivery, that is, ineligible for expectant management, and (2) those eligible for expectant management. The primary outcome was composite postpartum maternal morbidity, which included maternal intensive care unit admission, stroke, death, and other severe morbidities. The secondary outcomes included select adverse perinatal outcomes. Groups were compared and adjusted odds ratios (95% confidence intervals) calculated. RESULTS: Of the 1172 women with preeclampsia identified during the study period, 543 with preeclampsia with severe features were included for analysis: 211 (39%) were ineligible for expectant management and 332 (61%) were eligible for expectant management. Baseline characteristics, including age, body mass index, race and ethnicity, parity, marital status, and gestational age at preeclampsia diagnosis, were similar between the 2 groups. Women ineligible for expectant management had significantly higher composite postpartum maternal morbidity (adjusted odds ratio, 5.02 [95% confidence interval, 1.35-18.69]). In addition, those ineligible for expectant management were more likely to have postpartum intensive care unit admission (adjusted odds ratio, 4.19 [95% confidence interval, 1.09-16.16]) and postpartum hemoglobin level of <7 g/dL (adjusted odds ratio, 5.07 [95% confidence interval, 1.35-19.08]). There was no demonstrable difference in neonatal outcomes between the 2 groups. CONCLUSION: Women with preeclampsia with severe features who were ineligible for expectant management per the American College of Obstetricians and Gynecologists guidelines had a 5-fold increased risk of maternal morbidity, confirming the need for escalation of care and delivery without delay.

Outcomes before and after Adopting Guidelines for Expectant Management of Severe Preeclampsia.

OBJECTIVE: This study aimed to compare maternal and neonatal outcomes in women with severe preeclampsia before and after implementation of the American College of Obstetricians and Gynecologists (ACOG) taskforce hypertensive guidelines. STUDY DESIGN: Single-center retrospective cohort study of women with severe preeclampsia delivering live nonanomalous singletons 23 to 342/7 weeks from 2013 to 2017. In 2015, the ACOG guidelines for expectant management of severe preeclampsia were implemented at our institution. Based on this, patients were categorized as preguideline (January 2013-December 2015) or postguideline adoption (January 2016-December 2017). Primary outcomes included composite maternal morbidity and composite neonatal morbidity; secondary outcomes included composite components, length of stay, birth weight, and delivery gestational age. Groups were compared with Student's t-test, Chi-square, and Wilcoxon's rank-sum tests; adjusted odds ratios (aOR; 95% confidence intervals [CIs]) were calculated. Yearly composite outcomes were compared using the Cochran-Armitage trend test. We estimated a sample size of 250 per group would provide 80% power at α = 0.05 to detect a 50% reduction in neonatal morbidity from a baseline rate of 21.5%. RESULTS: From 2013 to 2017, a total of 543 women with severe preeclampsia were identified: 278 (51%) preguideline and 265 (49%) postguideline. Baseline characteristics were overall similar between groups. There were no significant differences in maternal (aOR = 0.96, 95% CI: 0.6-1.41) or neonatal (aOR = 0.88, 95% CI: 0.61-1.28) composite morbidity between groups. Furthermore, there were no differences in composite maternal or neonatal morbidity over time. CONCLUSION: Perinatal outcomes were similar before and after implementation of severe preeclampsia management guidelines at our institution. Studies to evaluate if benefits are limited to subsets of this population, such as earlier gestational ages, are needed. KEY POINTS: · Expectant management of severe preeclampsia has yet to be fully evaluated outside of trial conditions.. · We did not see a significant improvement in neonatal composite morbidity/mortality.. · We also did not see a worsened composite maternal morbidity/mortality..

Mid-Trimester Cervical Length Screening: Effect of Poorly Developed Lower Uterine Segment on Pregnancy Outcome.

OBJECTIVES: To identify whether a poorly developed lower uterine segment (PDLUS) observed during cervical length (CL) screening affects the duration of gestation in women with no prior spontaneous preterm birth (sPTB). MATERIALS AND METHODS: A retrospective cohort study of women with a singleton gestation and no prior sPTB, who underwent transvaginal CL screening at our institution. We excluded women with progesterone exposure, major anomalies, and women delivering elsewhere. Women with PDLUS were compared to those with a measured (normal) CL ≥25 mm. PRIMARY OUTCOME: birth gestational age (GA). SECONDARY OUTCOMES: sPTB <35 and 37 weeks, hospital evaluation for preterm labor without delivery, delivery indication, and mode. A Cox proportional-hazards survival model considered time from CL scan to delivery. We powered the study to detect a one-half week difference in birth GA. RESULTS: We included 270 women with PDLUS and 985 women with normal CL. Mean birth GA was 38.9 ± 2.0 weeks with PDLUS versus 38.7 ± 2.4 weeks with normal CL (p = .10). Women with PDLUS were less likely to experience sPTB <37 weeks (1.1% vs 3.6%; p = 0.04). There was no difference in sPTB <35 weeks (0.8% vs 1.7%; p = .25). Hospital evaluation for preterm labor (17% vs 19%; p = .54), delivery indication, and mode were not different. The hazard ratio for earlier birth in women with PDLUS was 0.67 (95% CI 0.46, 0.98; p = .04). CONCLUSIONS: We observed no difference in mean GA at birth; however, PDLUS was protective against sPTB <37 weeks and was associated with a lower hazard ratio for earlier birth.

Resident Operative Vaginal Delivery Volume after Educational Curriculum Implementation.

OBJECTIVE: The percentage of operative vaginal deliveries (OVDs) in the United States has sharply declined. In May 2016, our institution's obstetrics and gynecology (OB/GYN) residency program implemented a twice-yearly OVD curriculum consisting of didactics and simulation. We sought to evaluate the impact of this curriculum. STUDY DESIGN: We performed a retrospective cohort study of all deliveries at our institution from July 2011 to May 2018. Deliveries were evaluated quarterly for the pre- (July 2011-April 2016) and postcurriculum (July 2016-May 2018) periods. Forceps-assisted vaginal delivery (FAVD), vacuum-assisted vaginal delivery (VAVD), and total OVD percentages, and the ratio of forceps to vacuums were calculated. Pre- and postcurriculum percentages were compared using Wilcoxon's rank-sum test. Cubic regression curves were fit to quarterly percentages to illustrate trends over time. RESULTS: The quarterly OVD percentage was unchanged following curriculum implementation (mean 3.2% [Q1-Q3: 2.6-3.5%] pre- vs. 3.1% [2.5-3.8%] post-, p > 0.99). The FAVD percentage was increased (1.2% [0.8-1.5%] vs. 2.0% [1.4-2.6%], p = 0.027) and the VAVD percentage was decreased (2.0% [1.6-2.2%] vs. 1.2% [0.9-1.3%], p < 0.001). This was accompanied by an increase in the ratio of FAVD to VAVD (0.6 [0.4-0.8] vs. 1.7 [1.3-2.2], p < 0.001). FAVD percentage (3.1%) was higher in the last quarter than any other quarter in the 7-year study period, and total OVD percentage (3.9%) was higher in 2018 than any other calendar year. CONCLUSION: The implementation of an OVD curriculum in our OB/GYN residency program resulted in an increase in the percentage of FAVD and the ratio of FAVD to VAVD. KEY POINTS: · OVD utilization in the United States continues to decline.. · We demonstrate real-world impact of an OVD curriculum.. · OVD curriculum implementation increases usage of FAVD..

Labor Curve Analysis of Medically Indicated Early Preterm Induction of Labor.

OBJECTIVE: To analyze the labor curves of nulliparous and multiparous women between 23.0 and 34.0 weeks of gestation who underwent induction of labor and achieved vaginal delivery. METHODS: This is a retrospective cohort study of all live singletons delivered vaginally after medically indicated induction of labor between 23.0 and 34.0 weeks of gestation from 2011 through 2014 at our institution. We excluded those with one or no cervical examinations available during labor. Prior cesarean delivery, 5-minute Apgar score less than 5, and arterial cord pH less than 7.0 were exclusions. The course of cervical dilation was modeled using repeated measures analysis, and smoothed curves for nulliparous and parous women were generated separately. Estimates of the median (5th-95th percentile) traverse times between two dilations were computed using interval censored regression. Traverse times (ie, the elapsed time between two given dilation measures) were compared between nulliparous and parous women. RESULTS: Sixty-seven nulliparous and 69 multiparous women were included. Each group exhibited similar rates of change from 1 to 3 cm of dilation (median 3.6 hours nulliparous and 3.4 hours multiparous, P=.90). Nulliparous women progressed from 3 to 6 cm more slowly than multiparous women (median 10 hours vs 4.4 hours, P<.001). After 6 cm, both groups rapidly progressed to 10 cm (median 0.3 hours vs 0.3 hours, P=.64). Although the 95th percentile traverse time from 6 to 10 cm was about 2 hours in each group, progression from 1 to 6 cm at the 95th percentile was much longer (64.0 vs 42.2 hours). CONCLUSION: Early preterm labor induction takes less time in multiparous women owing to more rapid progression from 3 to 6 cm. At the 95th percentile, both nulliparous and multiparous women delivered vaginally, even with latent labor lasting well longer than 24 hours.

Sensitivity of prenatal ultrasound for detection of trisomy 18.

Objectives: To evaluate the sensitivity of prenatal ultrasound (US) for trisomy (T18) diagnosis and describe US findings in a large tertiary care institution in the USA. Materials and methods: This was a retrospective cohort of all T18 cases diagnosed at our institution from October 2004 to October 2014 based on prenatal or postnatal genetic diagnostic testing. We included all women with a fetus affected by T18 who had a comprehensive US by a maternal-fetal medicine specialist performed at our institution. US findings were reviewed, classified by organ system, and categorized as an anomaly or soft marker. Chi-square or t-test was used for statistical analysis. Results: We included 128 cases of T18 with confirmed cytogenetic analysis -110 (86%) of which were diagnosed prenatally or suspected by cell-free DNA and confirmed postnatally, and 18 of which underwent neonatal blood sampling alone. One hundred and twenty-one (95%) had at least one abnormal US finding. Anomalies were more frequently identified on US at ≥20 weeks as compared with <20 weeks (93% versus 76%; p = .004). The mean number of findings detected per fetus was 5.1 ± 3.0. Fetuses diagnosed by postnatal sampling alone had a similar number of US exams performed and number of abnormal findings compared to those diagnosed prenatally. Conclusion: Ninety-five percent of fetuses with T18 had at least one abnormal US finding. This sensitivity of is higher than reported in most prior studies, but is not 100%, and should be considered when counseling women regarding prenatal diagnosis of T18. Rationale: Historical detection rates for abnormal sonographic findings in trisomy 18 fetuses range from 70% to 100%. These studies are limited by small sample sizes. This is a contemporary study of ultrasound findings in a large group of women with confirmed trisomy 18 by prenatal or postnatal genetic diagnosis. We provide expansive detail on soft markers and anomalies broken down by organ-system and gestational age.

Utilization of an Alternative Docetaxel-based Intraperitoneal Chemotherapy Regimen in Patients With Ovarian, Fallopian Tube or Primary Peritoneal Carcinoma: A Continued Need for Ovarian Cancer Patients.

OBJECTIVE: The objective of this study was to report the tolerability and toxicity of a regimen consisting of intravenous (IV) docetaxel and intraperitoneal (IP) cisplatin and paclitaxel with granulocyte colony-stimulating factor support. MATERIALS AND METHODS: We conducted a retrospective cohort study of patients with surgical stage II-IV epithelial ovarian, fallopian tube or primary peritoneal carcinoma treated with an outpatient IP chemotherapy regimen consisting of docetaxel 75 mg/m IV and cisplatin 75 mg/m IP day 1 followed by paclitaxel 60 mg/m IP day 8 every 21 days. Grade 3 and 4 toxicity, dose delays and reductions, port complications, and tolerability are reported. Outcomes, including response rate, progression-free survival (PFS), overall survival (OS) are also reported. RESULTS: A total of 60 patients received this IP regimen. Most common toxicities included neutropenia (47%), gastrointestinal (28%), and anemia (25%). Most patients (85%) experienced no IP port complications. Dose delay or reduction was required in 30% of patients. Two-thirds completed all prescribed cycles, with 80% of total planned cycles completed. Complete response was achieved for 88%, and 43% are currently without evidence of disease. Median PFS for all patients was 25.5 months (95% confidence interval [CI], 20.4-30.5 mo) while OS for all patients was 56.8 months (95% CI, 47.7-65.9 mo). For the 44 patients with stage III disease, median PFS was 22.1 months (95% CI, 16.3-28.0 mo), while median OS was 56.8 months (95% CI, 47.3-66.3 mo). CONCLUSIONS: This docetaxel-based IP chemotherapy regimen demonstrates an improved tolerability profile compared with GOG172. Additional evaluations on alternative IP regimens remain warranted. Short follow-up time limits survival assessment, but results are encouraging.

Pregnancy Outcomes of Exacerbated Chronic Hypertension Compared with Superimposed Preeclampsia.

OBJECTIVE: Compare outcomes in women with chronic hypertension who remain normotensive, experience exacerbation, or meet laboratory criteria for superimposed preeclampsia. STUDY DESIGN: This is a retrospective cohort study of singleton pregnancies with chronic hypertension from 2000 to 2014. Delivery admission records were used to categorize women into three groups: stable chronic hypertension, exacerbated hypertension, and superimposed preeclampsia. The primary outcomes were a neonatal composite of death, respiratory support, umbilical arterial pH < 7, 5-minute Apgar ≤3, and seizures, in addition to maternal severe hypertension requiring intravenous (IV) antihypertensives. RESULTS: In total, 270 women (31.3%) had stable hypertension, 429 (49.8%) had exacerbated hypertension, and 163 (18.9%) had superimposed preeclampsia. Neonatal composite (10.7 vs. 11.2 vs. 21.5%; p < 0.01) and preterm birth <35 weeks (8.8 vs. 18.3 vs. 35.7%; p < 0.01) were highest in the superimposed preeclampsia group. Severe hypertension requiring the use of IV antihypertensives increased across groups (0 vs. 15.6 vs. 23.3% p < 0.01). With the exception of severe hypertension requiring IV antihypertensive use, outcomes in women with exacerbations were unchanged compared with those with stable hypertension. CONCLUSION: Superimposed preeclampsia is associated with an increased risk of adverse neonatal outcomes compared with stable chronic hypertension, whereas exacerbation of chronic hypertension is not.

Improved outcomes with dose-dense paclitaxel-based neoadjuvant chemotherapy in advanced epithelial ovarian carcinoma.

OBJECTIVE: We compared tolerability, toxicity, response, and interval debulking surgery (IDS) outcomes between patients who received weekly dose-dense paclitaxel (DDP) and every three-week platinum to standard every three-week taxane plus platinum neoadjuvant chemotherapy (NACT) for advanced epithelial ovarian cancer (EOC). METHODS: We conducted a retrospective study of patients receiving NACT at our center between June 1, 2012 and July 31, 2015. Patients with stage III/IV EOC who received at least one cycle of DDP (weekly paclitaxel plus every three-week carboplatin) or standard taxane (every three-week paclitaxel or docetaxel plus carboplatin) therapy were included. Abstracted data included demographics, tolerability, grade 3/4 toxicity, response, and IDS outcomes. Fisher's exact and student t-test were used for statistical significance. RESULTS: Twenty-one patients received DDP and 40 received standard taxane. Tolerability was comparable. More patients receiving DDP experienced grade 3 or 4 toxicity when considered in aggregate (86% vs. 40%; p=0.001). Pathologic complete response (pCR) was achieved in 14% of DDP patients versus 3% of standard (p=0.11). 48% of patients in the DDP group were debulked to no residual disease (NRD) versus 28% in the standard group (p=0.16). CONCLUSIONS: While associated with an increase in severe toxicity compared to standard three-week taxane, DDP appears to facilitate higher rates of pCR and NRD for patients receiving NACT in this preliminary study. These results warrant further investigation of DDP for patients with advanced EOC and assessment of impact on long-term survival outcomes.

Evaluation of Human Papillomavirus as a Risk Factor for Preterm Birth or Pregnancy-Related Hypertension.

OBJECTIVE: To compare rates of preterm birth and pregnancy-related hypertension in women with and without human papillomavirus (HPV) infection. METHODS: We performed a retrospective cohort study of all women delivered at our institution in 2013 who had cervical cancer screening test results within 3 years before delivery. Patients were excluded if they had prior procedure(s) for cervical dysplasia other than biopsy. There were two primary outcomes: preterm birth (less than 37 weeks of gestation) and pregnancy-related hypertension (gestational hypertension, preeclampsia, or eclampsia). Multivariable logistic regression was performed to adjust for confounders including demographic variables, diabetes, prior preterm birth, chronic hypertension, and other genital infections. Assuming a 10% prevalence of HPV, a rate of 12% in the HPV-negative group for both preterm birth and pregnancy-related hypertension, α of 0.05, and ß of 0.2, we needed 2,207 patients to detect a 60% increase in the rate of either outcome in the HPV-positive group. RESULTS: A total of 3,958 patients delivered in 2013, of whom 2,321 met eligibility criteria, 242 (10.4%) of whom were HPV-positive and 2,079 (89.2%) of whom were HPV-negative. In multivariate analyses, the rate of preterm birth was not significantly different between HPV-positive and HPV-negative women (16.5% compared with 12.2%, adjusted odds ratio [OR] 1.3, 95% confidence interval [CI] 0.9-1.9); rates of pregnancy-related hypertension also were not significantly different between HPV-positive and HPV-negative women (17.0% compared with 16.4%, adjusted OR 1.0, 95% CI 0.7-1.5). CONCLUSION: Maternal HPV infection is not an independent risk factor for preterm birth or pregnancy-related hypertension.

Autocrine adenosine signaling promotes regulatory T cell-mediated renal protection.

Regulatory T cells (Tregs) suppress the innate inflammation associated with kidney ischemia-reperfusion injury (IRI), but the mechanism is not well understood. Tregs express CD73, the final enzyme involved in the production of extracellular adenosine, and activation of the adenosine 2A receptor (A(2A)R) on immune cells suppresses inflammation and preserves kidney function after IRI. We hypothesized that Treg-generated adenosine is required to block innate immune responses in kidney IRI and that the Treg-generated adenosine would signal through A(2A)Rs on inflammatory cells and, in an autocrine manner, on Tregs themselves. We found that adoptively transferred wild-type Tregs protected wild-type mice from kidney IRI, but the absence of adenosine generation (CD73-deficient Tregs) or adenosine responsiveness (A(2A)R-deficient Tregs) led to inhibition of Treg function. Pharmacologic stimulation of A(2A)R before adoptive transfer augmented the ability of wild-type and CD73-deficient Tregs to suppress kidney IRI. Microarray analysis and flow cytometry revealed that A(2A)R activation enhanced surface PD-1 expression on Tregs in the absence of any other activation signal. Treatment of Tregs with a PD-1 blocking antibody before adoptive transfer reversed their protective effects, even if pretreated with an A(2A)R agonist. Taken together, these results demonstrate that the simultaneous ability to generate and respond to adenosine is required for Tregs to suppress innate immune responses in IRI through a PD-1-dependent mechanism.

Neuroprotective antioxidant STAZN protects against myocardial ischemia/reperfusion injury.

BACKGROUND: Protecting the myocardium from ischemia-reperfusion injury has significant potential to reduce the complications of myocardial infarction and interventional revascularization procedures. Reperfusion damage is thought to result, in part, from oxidative stress. Here we use a novel method of percutaneous coronary occlusion to show that the potent antioxidant and neuroprotective free-radical scavenger, stilbazulenyl nitrone (STAZN), confers marked cardioprotection when given immediately prior to reperfusion. METHODS AND RESULTS: Physiologically controlled male Sprague-Dawley rats were anesthetized with isoflurane, paralyzed with pancuronium and mechanically ventilated. A guide wire was introduced via the femoral artery and advanced retrogradely via the aorta into the left coronary artery under fluoroscopic guidance. Rats with established coronary ischemia (85 min after occlusion) were given STAZN 3.5 mg/kg or its vehicle 5 min before and 2 h after reperfusion, and were subjected to functional and histopathologic studies at 3 days. Ischemia-associated Q wave amplitude was reduced by 73% in STAZN-treated rats (P=0.01), while infarct-related ejection fraction, fractional shortening and severe regional wall-motion impairments were improved by 48%, 54% and 37%, respectively, relative to vehicle-treated controls (P=0.05). Total myocardial infarct volume in STAZN-treated rats was correspondingly reduced by 43% (P<0.05), representing a sparing of 14% of the total left ventricular myocardium. CONCLUSIONS: STAZN, a second-generation azulenyl nitrone with potent neuroprotective efficacy in brain ischemia, is also a rapidly acting and highly effective cardioprotective agent in acute coronary ischemia. Our results suggest the potential for clinical benefit in the setting of acute coronary syndromes.

Neuroprotective effect of STAZN, a novel azulenyl nitrone antioxidant, in focal cerebral ischemia in rats: dose-response and therapeutic window.

Stilbazulenyl nitrone (STAZN) is a potent antioxidant that, in a rat model of transient focal cerebral ischemia, confers significant enduring functional and morphological neuroprotection. This study investigated the influence of dose and time of administration on the neuroprotective effects of STAZN in the intraluminal suture model of middle cerebral artery occlusion (MCAo). Dose response: At 2 and 4 h after the onset of MCAo, animals received intravenously either STAZN (low dose=0.07 mg/kg, n=8; medium dose=0.7 mg/kg, n=9; high dose=3.5 mg/kg, n=9), an equivalent volume of vehicle (30% Solutol HS15 and 70% isotonic saline, 0.37 ml/kg, n=5) or saline (0.37 ml/kg, n=5). Only the medium dose improved scores (p<0.05) on a standardized neurobehavioral test at 1, 2 and 3 days after MCAo. Only the medium dose reduced the total infarction (51%, p=0.014) compared to controls. These results indicate that STAZN exhibits maximal neuroprotection at the 0.7 mg/kg dose. Therapeutic window: STAZN (0.6 mg/kg) dissolved in dimethylsulfoxide was given intra-peritoneally at 2 and 4 h (n=11), 3 and 5 h (n=10), 4 and 6 h (n=10) or 5 and 7 h (n=7) after the onset of MCAo. Additional doses were given at 24 and 48 h. Vehicle (dimethylsulfoxide, 2.0 ml/kg, n=6) was administered at 3, 5, 24 and 48 h. STAZN treatment initiated at 2 or 3 h after the onset of MCAo improved neurological scores (p<0.001) and reduced total infarction (42.2%, p<0.05) compared to controls.

Stilbazulenyl nitrone, a second-generation azulenyl nitrone antioxidant, confers enduring neuroprotection in experimental focal cerebral ischemia in the rat: neurobehavior, histopathology, and pharmacokinetics.

Stilbazulenyl nitrone (STAZN) is a potent lipophilic second-generation azulenyl nitrone antioxidant, which is highly neuroprotective in rodent models of cerebral ischemia and trauma. This study was conducted to establish whether the neuroprotection induced by STAZN persists with chronic survival and to characterize STAZN's pharmacokinetics. Physiologically regulated rats received a 2-h middle cerebral artery occlusion by intraluminal suture and were treated with either STAZN [four 0.6 mg/kg doses i.p. administered at 2 (i.e., onset of recirculation), 4, 24, and 48 h; n = 16] or dimethyl sulfoxide vehicle (n = 11). They received sequential neurobehavioral examinations followed by quantitative neuropathology at 30 days. STAZN improved neurological deficits compared with vehicle controls, beginning within <2 h of the first dose and persisting throughout a 30-day survival. Large cystic necrotic infarcts were common in vehicle-treated rats but infrequent in STAZN-treated rats, and noninfarcted forebrain tissue was increased on average by 15%. In normal rats administered 5 mg/kg STAZN i.v. in Solutol HS 15/ethanol/saline vehicle, STAZN blood levels exhibited a biexponential decline, with an initial half-life of 28 min and a subsequent slow decay with half-life of approximately 7 h. STAZN tissue levels at 2 to 3 h were, on average, 2.5% of blood levels in forebrain, 56% in myocardium, and 41% in kidney. STAZN was concentrated in liver with initial concentrations averaging 5.2-fold above blood levels and a subsequent linear decline of 40% between 24 and 72 h. These results establish that STAZN confers enduring ischemic neuroprotection, has a long circulating half-life, and penetrates well into brain and other organs-characteristics favoring its potential therapeutic utility.

A novel azulenyl nitrone antioxidant protects against MPTP and 3-nitropropionic acid neurotoxicities.

Oxidative stress plays an important role in neuronal death in neurodegenerative disorders such as Parkinson's disease (PD) and Huntington's disease (HD). Animal models of PD or HD, produced by administration of the mitochondrial toxins 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) or 3-nitropropionic acid (3NP), respectively, show increased free radical generation. Free radicals generated in biological systems can react with spin-trapping compounds, such as nitrones, to form stable adducts. In recent years, the utility of nitrones has moved beyond analytical applications and into the realm of neuroprotection as antioxidants in both brain ischemia and models of neurodegenerative diseases. In the present study, we administered a new nitrone antioxidant, stilbazulenyl nitrone (STAZN), with either MPTP or 3NP. STAZN attenuated MPTP-induced striatal dopamine depletion by 40% and showed a tendency to dose-dependent neuroprotection. STAZN dose-dependently protected against loss of tyrosine hydroxylase immunoreactive neurons in the substantia nigra pars compacta. STAZN reduced the striatal lesion volume caused by systemic 3NP administration from 44 +/- 9 to 20 +/- 6 mm(3). The lipid peroxidation marker, malondialdehyde(MDA), was significantly increased in the striatum, cortex, and cerebellum of rats after administration of 3NP. These increases were blocked by co-injection of STAZN. Our data provide further evidence that STAZN is a neuroprotective free radical spin trap, and suggest that the development of new antioxidants will broaden our therapeutic strategies for neurodegenerative diseases.

Kinetic studies on stilbazulenyl-bis-nitrone (STAZN), a nonphenolic chain-breaking antioxidant in solution, micelles, and lipid membranes.

The rate constants, k(inh), for reaction of stilbazulenyl-bis-nitrone (STAZN, 1) with peroxyl radicals and the number of radicals trapped, n, are compared with those of phenolic antioxidants 2,2,5,7,8-pentamethyl-6-hydroxychroman (PMHC, 4a), 2,5,7,8-tetramethyl-6-hydroxychroman-2-carboxylic acid (Trolox, 4b), and 2,6-di-tert-butyl-4-methoxyphenol (DBHA, 5). The behavior of STAZN depended markedly on the media and type of initiator used, water-soluble or lipid-soluble. In styrene/chlorobenzene and initiation by azo-bis(isobutyronitrile) (AIBN), k(inh) (STAZN) = 0.64 k(inh) (5) = 0.02k(inh) (4a). On addition of methanol, the k(inh) of STAZN increased 6-fold to be four times that of 5 while that of 4a decreased 6-fold. In aqueous SDS-micelles containing methyl linoleate and initiation with water-soluble azo-bis(amidinopropane)2HCl, ABAP, the relative k(inh) values were 1 >or= 4b > 5. In dilinoleoylphosphatidyl choline (DLPC) bilayers and initiation with lipid-soluble azo-bis-2,4(dimethylvaleronitrile) (DMVN), the k(inh) order was 5 > 4b > 1. During initiation with ABAP in micelles and bilayers, the calculated values of k(inh) for STAZN changed during the induction period. The experimental results are interpreted in terms of the conformation of STAZN, which is transoid in homogeneous solution but cisoid in aqueous dispersions of lipids. In such dispersions, the STAZN lies at the lipid-water interface where it traps water-soluble peroxyl radicals by a single electron-transfer mechanism. The cisoid conformation at lipid-water interfaces is supported by theoretical calculations.

Stilbazulenyl nitrone, a novel antioxidant, is highly neuroprotective in focal ischemia.

Azulenyl nitrones are novel chain-breaking antioxidants with low oxidation potentials and high lipophilicity-properties favoring their efficacy as neuroprotectants. We tested the second-generation azulenyl nitrone, stilbazunenlyl nitrone (STAZN), in focal ischemic stroke. Physiologically monitored rats received 2 hours of middle cerebral artery occlusion by intraluminal suture, resulting in substantial cortical and striatal infarcation. Neurobehavior was quantified on a standard battery, and brains were perfusion-fixed for quantitative histopathology at 3 days. In 3 independent series, rats were treated at either 2h + 4h, or 2h + 4h + 24h + 48h, after onset of ischemia; vehicle-treated rats received dimethylsulfoxide or saline. All animals (n = 52) developed high-grade neurological deficits (score 11 of 12) during ischemia, which improved, in STAZN-treated rats, within 1-1.5 h of the initial dose and fell to a median score of 3 at 72 h, compared to 8 in vehicle rats. STAZN treatment reduced mean cortical infarct volume by 64-97%, and total infarct volume by 42-72%. In over one-half of STAZN-treated animals, cortical infarction was virtually abolished. Regression analysis predicted that STAZN would confer approximately 50% cortical neuroprotection even in the most severely affected cases. The potency of STAZN was orders-of-magnitude greater than other nitrones such as NXY-059. These results suggest that STAZN has great promise for ischemic stroke.

Stilbazulenyl nitrone, a novel azulenyl nitrone antioxidant: improved neurological deficit and reduced contusion size after traumatic brain injury in rats.

OBJECT: Stilbazulenyl nitrone (STAZN) is a second-generation azulenyl nitrone that has markedly enhanced antioxidant properties compared with those of conventional alpha-phenyl nitrones. In this study, the authors assessed the potential efficacy of STAZN in a rodent model of fluid-percussion brain injury, which results in a consistent cortical contusion. METHODS: After anesthesia had been induced in normothermic Sprague-Dawley rats (brain temperature 36-36.5 degrees C) by halothane-nitrous oxide, the animals were subjected to a right parietooccipital parasagittal fluid-percussion injury (1.5-2 atm). The agent (STAZN, 30 mg/kg: eight animals) or vehicle (dimethyl sulfoxide; eight animals) was administered intraperitoneally at 5 minutes and 4 hours after trauma. The neurological status of each rat was evaluated on Days 1, 2, and 7 postinjury (normal score 0, maximum injury 12). Seven days after trauma, the rat brains were perfusion fixed, coronal sections at various levels were digitized, and areas of contusion were measured. Treatment with STAZN significantly improved neurological scores on Days 2 and 7 postinjury compared with vehicle-treated rats. Administration of STAZN also significantly reduced the total contusion area by 63% (1.8 +/- 0.5 mm2 in STAZN-treated animals compared with 4.8 +/- 2.1 mm2 in vehicle-treated animals; p = 0.04) and the deep cortical contusion area by 60% (1.2 +/- 0.2 mm2 in STAZN-treated animals compared with 2.9 +/- 1.2 mm2 in vehicle-treated animals; p = 0.03). By contrast, hippocampal cell loss in the CA3 sector was unaffected by STAZN treatment. CONCLUSIONS: Therapy with STAZN, a novel potent antioxidant, administered following traumatic brain injury, markedly improves neurological and histological outcomes. Azulenyl nitrones appear to represent a promising class of neuroprotective agents for combating this devastating condition.