Soft x-ray images of the laser entrance hole of ignition hohlraums

Hohlraums are employed at the national ignition facility to convert laser energy into a thermal x-radiation drive, which implodes a fusion capsule, thus compressing the fuel. The x-radiation drive is measured with a low spectral resolution, time-resolved x-ray spectrometer, which views the region around the hohlraum's laser entrance hole. This measurement has no spatial resolution. To convert this to the drive inside the hohlraum, the size of the hohlraum's opening ("clear aperture") and fraction of the measured x-radiation, which comes from this opening, must be known. The size of the clear aperture is measured with the time integrated static x-ray imager (SXI). A soft x-ray imaging channel has been added to the SXI to measure the fraction of x-radiation emitted from inside the clear aperture. A multilayer mirror plus filter selects an x-ray band centered at 870 eV, near the peak of the x-ray spectrum of a 300 eV blackbody. Results from this channel and corrections to the x-radiation drive are discussed.

Precision shock tuning on the national ignition facility

Ignition implosions on the National Ignition Facility [J. D. Lindl et al., Phys. Plasmas 11, 339 (2004)] are underway with the goal of compressing deuterium-tritium fuel to a sufficiently high areal density (ρR) to sustain a self-propagating burn wave required for fusion power gain greater than unity. These implosions are driven with a very carefully tailored sequence of four shock waves that must be timed to very high precision to keep the fuel entropy and adiabat low and ρR high. The first series of precision tuning experiments on the National Ignition Facility, which use optical diagnostics to directly measure the strength and timing of all four shocks inside a hohlraum-driven, cryogenic liquid-deuterium-filled capsule interior have now been performed. The results of these experiments are presented demonstrating a significant decrease in adiabat over previously untuned implosions. The impact of the improved shock timing is confirmed in related deuterium-tritium layered capsule implosions, which show the highest fuel compression (ρR~1.0 g/cm(2)) measured to date, exceeding the previous record [V. Goncharov et al., Phys. Rev. Lett. 104, 165001 (2010)] by more than a factor of 3. The experiments also clearly reveal an issue with the 4th shock velocity, which is observed to be 20% slower than predictions from numerical simulation.

Assembly of high-areal-density deuterium-tritium fuel from indirectly driven cryogenic implosions

The National Ignition Facility has been used to compress deuterium-tritium to an average areal density of ~1.0±0.1 g cm(-2), which is 67% of the ignition requirement. These conditions were obtained using 192 laser beams with total energy of 1-1.6 MJ and peak power up to 420 TW to create a hohlraum drive with a shaped power profile, peaking at a soft x-ray radiation temperature of 275-300 eV. This pulse delivered a series of shocks that compressed a capsule containing cryogenic deuterium-tritium to a radius of 25-35 μm. Neutron images of the implosion were used to estimate a fuel density of 500-800 g cm(-3).

Demonstration of ignition radiation temperatures in indirect-drive inertial confinement fusion hohlraums

We demonstrate the hohlraum radiation temperature and symmetry required for ignition-scale inertial confinement fusion capsule implosions. Cryogenic gas-filled hohlraums with 2.2 mm-diameter capsules are heated with unprecedented laser energies of 1.2 MJ delivered by 192 ultraviolet laser beams on the National Ignition Facility. Laser backscatter measurements show that these hohlraums absorb 87% to 91% of the incident laser power resulting in peak radiation temperatures of T(RAD)=300 eV and a symmetric implosion to a 100 μm diameter hot core.

Observation of high soft x-ray drive in large-scale hohlraums at the National Ignition Facility

The first soft x-ray radiation flux measurements from hohlraums using both a 96 and a 192 beam configuration at the National Ignition Facility have shown high x-ray conversion efficiencies of ∼85%-90%. These experiments employed gold vacuum hohlraums, 6.4 mm long and 3.55 mm in diameter, heated with laser energies between 150-635 kJ. The hohlraums reached radiation temperatures of up to 340 eV. These hohlraums for the first time reached coronal plasma conditions sufficient for two-electron processes and coronal heat conduction to be important for determining the radiation drive.

The first measurements of soft x-ray flux from ignition scale Hohlraums at the National Ignition Facility using DANTE (invited)

The first 96 and 192 beam vacuum Hohlraum target experiments have been fielded at the National Ignition Facility demonstrating radiation temperatures up to 340 eV and fluxes of 20 TW/sr as viewed by DANTE representing an ∼20 times flux increase over NOVA/Omega scale Hohlraums. The vacuum Hohlraums were irradiated with 2 ns square laser pulses with energies between 150 and 635 kJ. They produced nearly Planckian spectra with about 30±10% more flux than predicted by the preshot radiation hydrodynamic simulations. To validate these results, careful verification of all component calibrations, cable deconvolution, and software analysis routines has been conducted. In addition, a half Hohlraum experiment was conducted using a single 2 ns long axial quad with an irradiance of ∼2×10(15) W/cm(2) for comparison with NIF Early Light experiments completed in 2004. We have also completed a conversion efficiency test using a 128-beam nearly uniformly illuminated gold sphere with intensities kept low (at 1×10(14) W/cm(2) over 5 ns) to avoid sensitivity to modeling uncertainties for nonlocal heat conduction and nonlinear absorption mechanisms, to compare with similar intensity, 3 ns OMEGA sphere results. The 2004 and 2009 NIF half-Hohlraums agreed to 10% in flux, but more importantly, the 2006 OMEGA Au Sphere, the 2009 NIF Au sphere, and the calculated Au conversion efficiency agree to ±5% in flux, which is estimated to be the absolute calibration accuracy of the DANTEs. Hence we conclude that the 30±10% higher than expected radiation fluxes from the 96 and 192 beam vacuum Hohlraums are attributable to differences in physics of the larger Hohlraums.

Images of the laser entrance hole from the static x-ray imager at NIF

The static x-ray imager at the National Ignition Facility is a pinhole camera using a CCD detector to obtain images of Hohlraum wall x-ray drive illumination patterns seen through the laser entrance hole (LEH). Carefully chosen filters, combined with the CCD response, allow recording images in the x-ray range of 3-5 keV with 60 μm spatial resolution. The routines used to obtain the apparent size of the backlit LEH and the location and intensity of beam spots are discussed and compared to predictions. A new soft x-ray channel centered at 870 eV (near the x-ray peak of a 300 eV temperature ignition Hohlraum) is discussed.

Creation of hot radiation environments in laser-driven targets

A hot radiation environment, produced by maximizing laser-energy deposition into a small, high- "can," is a platform being developed for investigations of material properties under extreme conditions. In such small targets, almost doubling the laser energy results in only an incremental increase in the x-radiation flux, and almost no increase in the maximum achieved radiation temperature. That most of this additional laser energy is not deposited within the target is a direct consequence of laser-plasma interactions (LPI) outside of the target, which result in high-angle beams never entering the target late in the laser pulse. Accounting for these processes in the modeling results in quantitative agreement for the first time with experiments using very small cans. These findings have provided the scientific foundation for modifying the target geometry to mitigate the LPI and to achieve higher radiation temperatures.

Radiation-driven hydrodynamics of high- hohlraums on the national ignition facility

The first hohlraum experiments on the National Ignition Facility (NIF) using the initial four laser beams tested radiation temperature limits imposed by plasma filling. For a variety of hohlraum sizes and pulse lengths, the measured x-ray flux shows signatures of filling that coincide with hard x-ray emission from plasma streaming out of the hohlraum. These observations agree with hydrodynamic simulations and with an analytical model that includes hydrodynamic and coronal radiative losses. The modeling predicts radiation temperature limits with full NIF (1.8 MJ), greater, and of longer duration than required for ignition hohlraums.

Endoscopic closure of fetal membrane defects: comparing iatrogenic versus spontaneous rupture cases

OBJECTIVE

Currently, physicians manage preterm premature rupture of membranes (PPROM) by expectant management or termination of the gestation. A therapy aimed at sealing membranes would be optimal to maintain the pregnancy and achieve a normal neonate. Our objective was to compare an endoscopic technique for intrauterine closure of fetal membrane defects after both iatrogenic and spontaneous rupture of membranes.

METHODS

Our technique was performed on four patients experiencing PPROM spontaneously and four patients after genetic amniocentesis. Intrauterine endoscopy allowed direct visualization of membrane defects. Rapid sequential injections of platelets, fibrin glue and powdered collagen slurry were administered at the site of the defect and of trocar placement. Sonography for amniotic fluid index, nitrazine and fern testing and pad count were performed after each procedure at three intervals: immediately post-procedure, and after 24 and 48 h.

RESULTS

Eight patients underwent endoscopic intrauterine sealing of ruptured membranes between 16 and 24 weeks of gestation: four were spontaneous ruptures and four were ruptures post-amniocentesis. In the post-amniocentesis group, three patients delivered viable infants at 26, 32 and 34 weeks. In one patient, the membranes ruptured again 12 h after the sealing procedure and she decided to undergo termination of pregnancy. Of the four spontaneous rupture patients, two experienced preterm labor and delivery within 2 days of the procedure. One patient was diagnosed with fetal demise 12 h post-procedure, and one patient delivered a neonate at 31 weeks of gestation with severe respiratory distress syndrome.

CONCLUSIONS

This technique for sealing ruptured membranes is effective after amniocentesis, but may not be of benefit with spontaneous rupture.

Perinatal outcomes in monoamniotic gestations

OBJECTIVE

A comprehensive review of monoamniotic twin gestations reported between 1990 and 2002 was performed to estimate current perinatal mortality and morbidity rates, as well as the predictive value of an antenatal diagnosis of cord entanglement for poor obstetric outcomes.

METHOD

A Medline literature review using the search term 'monoamniotic' and limited to articles published in the English language between 1990 and 2002 was performed.

RESULTS

A total of 133 continuing, non-conjoined twin monoamniotic pregnancies with delivery information were identified. Perinatal loss per 2-week interval was relatively constant at 2-4% from 15 to 32 weeks. However, of the 131 fetuses reaching 33 weeks, the percentage loss significantly increased to 11.0% at 33-35 weeks and 21.9% at 36-38 weeks compared to that at 30-32 weeks. Overall perinatal mortality was 23.3%. Of all losses, 61.2% involved both twins and 38.8% involved only one fetus. Cord entanglements were documented antenatally in 22.6% of reports. There was a statistically significant decrease in the average number of neonatal intensive care unit days for non-anomalous neonates (10.6 +/- 7.7 vs. 32.6 +/- 32.0), average gestational age at the time of delivery (30.4 +/- 7.6 vs. 32.6 +/- 4.1), as well as a decrease in the prevalence of total (8.3% vs. 27.7%) and non-anomalous (7.0% vs. 21.6%) perinatal mortality in pregnancies with an antenatal diagnosis of cord entanglement compared to those without the antenatal diagnosis of cord entanglement. The presence of fetal anomalies was associated with a 42.9% perinatal mortality rate.

CONCLUSIONS

Contrary to previous reports, there is a significant increase in the incidence of perinatal loss beyond 32 weeks among monoamniotic twins, suggesting that delivery after corticosteroid therapy should be strongly considered at this gestational age.

Management of cervical cerclage at term: remove the suture in labor?

OBJECTIVE

To assess the risks and benefits to patients who carry to term after undergoing a Shirodkar cerclage where the cerclage is not removed until the patient presents in labor.

METHODS

A retrospective analysis was conducted examining all patients who underwent a Shirodkar cerclage employing a 5 mm Mersilene band. All the cerclages were placed by a single operator over a twenty five year span, from 1/01/74 till 10/01/98. Only patients who delivered vaginally or were allowed a trial of labor were included. In all cases, the cerclage was removed under regional anesthesia after the patient presented to the hospital in labor.

RESULTS

Ninety six cerclage procedures were performed over that period. Eighty two pregnancies qualified for review. Sixty two patients delivered vaginally (76%). Nine cesareans were indicated for failure to progress in labor (11%) with cervical dystocia possibly implicated in one. There were no cases of ruptured uteri or the development of uterine windows. Of the 82 pregnancies there were five cases (6%) of minor cervical laceration.

CONCLUSION

Allowing patients to proceed to labor with a Shirodkar, cerclage in place, does not increase the risks of cervical dystocia, cervical laceration, or uterine rupture above the reported incidence for these complications in patients in whom the cerclage is removed prophylactically.

Minimally invasive endoscopy in the treatment of preterm premature rupture of membranes by application of fibrin sealant

We report only the 3rd case of closure of amniorrhexis following genetic amniocentesis. Our technique is the first to use endoscopic visualization of the rupture site and apply maternal platelets and fibrinogen/thrombin (Hemaseel Haemacure Corp Sarasota F1). The patient underwent repair at 20.6 weeks, 26 days after spontaneous rupture of membranes post-amniocentesis. At the time of the procedure the amniotic fluid index was 1 cm. Patient was delivered at 32.3 weeks secondary to complications of diabetes and severe preeclampsia. The neonate had APGARS of 7 at 1 min and 8 at 5 min and was discharged home on Day 21 of life.

Endoscopic ligation of umbilical cord at 19 week's gestation in monoamniotic monochorionic twins discordant for hypoplastic left heart syndrome

We report the first attempt of reduction of monoamniotic twins, discordant for hypoplastic left heart syndrome, using a new fetoscopic technique. Employing sonographic guidance and endoscopic visualization, cord ligation was accomplished, but significant cord entanglement, not previously appreciated, resulted in the ligation of the umbilical cord of the normal fetus. Cord entanglement may frustrate endoscopic techniques in monoamniotic twins.

Change in cervical length after cerclage as a predictor of preterm delivery

OBJECTIVE

To determine whether the degree of cervical lengthening after cerclage and whether serial follow-up measurements of cervical length after cerclage are predictive of pregnancy outcome.

METHODS

Eighty women whose primary physician determined that a prophylactic (n = 50) or urgent cerclage (n = 30) was indicated had transvaginal ultrasonographic evaluation before and after cerclage. Thereafter, most women had three additional transvaginal ultrasound examinations until 32 weeks' gestation. At each examination, the mean of three measurements was calculated. Statistical analyses were done by t test, analysis of variance, and logistic regression, with significance set at P <.05.

RESULTS

The mean +/- standard deviation precerclage cervical length was 27.2 +/- 10.3 mm and after cerclage was 34.1 +/- 9.9 mm (n = 80, P <.001, paired t test). No significant association was found (r = -0.26) between the difference in cervical length (postcerclage - precerclage lengths) and pregnancy outcome. Patients with a prophylactic cerclage had a mean cervical length that was consistently longer in patients delivering at term compared with those who delivered preterm at 20 to 32 weeks' gestation. In the urgent cerclage group a significant difference in cervical length between those who delivered at term compared with preterm was evident only at 28 to 32 weeks.

CONCLUSION

The increase in cervical length after cerclage is not predictive of term delivery. Serial cervical length measurements in the late second or early third trimester predict preterm birth but could provide earlier warning in patients with a prophylactic cerclage than in patients with urgent cerclage.

Intra amniotic candidiasis. Case report and meta-analysis of 54 cases

We present a case of mid pregnancy loss with retained intrauterine contraceptive device associated with fetal Candida infection. Review of English literature identified 53 additional cases of fetal candidal infection, with 17 associated with an IUCD in situ. The presence of an IUCD was associated with delivery at a statistically significant earlier gestational age when compared to cases not associated with an IUCD (23.3 +/- 4.9 vs 31.6 +/- 7.0, p < 0.001). Seventy-seven percent of fetal candidal infections associated with an IUCD were systemic (heart, brain, liver, gastrointestinal, lung) compared to 33% of cases not associated with an IUCD. In contrast to bacterial intraamniotic infections there was a low incidence of maternal febrile morbidity. An hypothesis as to the pathogenesis of Candidal infections in the presence and absence of an IUCD is offered as well as a paradigm for the management of the gravid patient with an IUCD in situ.

Change in cervical length after prophylactic cerclage

OBJECTIVE

To determine changes in length of incompetent cervices after cerclage, using transvaginal ultrasound.

METHODS

Patients were enrolled in a prospective, observational study under an Institutional Review Board-approved protocol. McDonald or Shirodkar sutures were placed according to physician preference. Pre- and postcerclage cervical lengths were measured within 72 hours of the procedure. At each examination, the first measurement was discarded, and a mean of the subsequent three measurements was calculated.

RESULTS

Twenty-one Shirodkar and ten McDonald operations were done. The mean (+/- standard deviation) precerclage cervical length was 2.7+/-0.9 cm and the postcerclage cervical length was 3.6+/-0.9 cm (P<.001, paired t test).

CONCLUSION

Prophylactic cerclage results in measurable increases in cervical length, which might contribute to the success of the procedure. Further study is needed to determine whether the degree of cervical lengthening after cerclage predicts term delivery.

Neuropsychiatric adverse effects of antiparkinsonian drugs. Characteristics, evaluation and treatment

Parkinson's disease (PD) is a progressive neurological condition that causes considerable disability in the elderly. Drugs used to treat PD, such as levodopa, offer symptomatic relief but often have neuropsychiatric adverse effects, most prominently psychosis and delirium. Aged patients and those with dementia are particularly vulnerable to these adverse effects. Evaluating PD patients with drug-induced neuropsychiatric adverse effects is made difficult by their complex clinical presentations. The treatment of drug-induced psychosis and delirium begins with manipulating the antiparkinsonian drug regimen, but this frequently worsens motor function. Atypical antipsychotics such as clozapine have been successfully employed to treat the psychosis without worsening the motor disability. Patient intolerance of clozapine therapy has prompted open-label studies with newer agents such as risperidone, remoxipride, zotepine, mianserin and ondansetron.

Tachycardia as the sole fetal heart rate abnormality after funipuncture

BACKGROUND

Fetal bradycardia is a common complication of funipuncture. We present a case of fetal exsanguination in which fetal tachycardia was the sole fetal heart rate abnormality.

CASE

Funipuncture was performed at 32 weeks' gestation for evaluation of Rh isoimmunization. A persistent fetal tachycardia ensued and, although there was no immediate ultrasound evidence of bleeding, repeat ultrasonography revealed active bleeding at the puncture site. A neonate with an initial hematocrit of 42% was delivered by cesarean. Despite aggressive replacement of blood products, a repeat hematocrit was only 35% and a severe, persistent coagulopathy ensued. The newborn died 18 hours after delivery. Autopsy findings were consistent with neonatal coagulopathy.

CONCLUSION

Although fetal bleeding is usually a common, relatively benign complication of funipuncture, streaming may not always be detected on ultrasonographic examination. Our case demonstrates that fetal tachycardia may be the only sign of fetal hemorrhage.

Flutamide-induced liver toxicity including fatal hepatic necrosis

PURPOSE

To describe hepatic injuries in three patients who received flutamide prior to and during radiation treatment to make radiation oncologists aware of the need for careful monitoring of liver function during use of this drug.

METHODS AND MATERIALS

The records of three patients who developed abnormal liver function tests while undergoing total androgen suppression (TAS), as well as the literature concerning flutamide toxicity were reviewed and summarized.

RESULTS

Three of 34 patients treated with a TAS regimen incorporating flutamide developed significant hepatic abnormalities: elevated transaminases [2] and fatal hepatic necrosis [1]. Following the discontinuation of flutamide, two patients recovered fully. Unfortunately, the third patient's hepatic function continued to deteriorate, which culminated in his death. Transient elevations in serum transaminases, which do not exceed four times the upper limits of normal, are common and apparently without clinical significance. Unfortunately, idiosyncratic serious and/or fatal liver damage can occur. Significant liver toxicity may be obviated by monitoring of liver function tests (LFT) early in the course of flutamide therapy.

CONCLUSION

The incidence of hepatic toxicity associated with flutamide may be higher than previously suggested. To prevent the development of serious hepatic dysfunction, all patients receiving flutamide should be monitored clinically for signs and symptoms referable to hepatic injury and with serial LFT. We recommend baseline LFT followed by serial LFT at weeks 2, 4, 6, and 8 from the start of treatment with flutamide. Flutamide should be stopped promptly if significant liver abnormalities are detected.

The role of nitric oxide in the pathogenesis of preeclampsia

OBJECTIVE

Nitric oxide, a potent vasodilator released by endothelial cells, inhibits platelet aggregation and adhesion to vascular endothelial surfaces. Because endothelial cell damage is considered pivotal in the pathogenesis of preeclampsia, this study was initiated to determine whether nitric oxide production is decreased in patients with preeclampsia.

STUDY DESIGN

Twenty-six patients with preeclampsia (as defined by a blood pressure > or = 140 mm Hg systolic or 90 mm Hg diastolic plus proteinuria, > or = 300 mg per 24 hours or > or = 2+ by dipstick, both occurring on two occasions > or = 4 hours apart) and 26 normotensive women with singleton gestations in the third trimester were studied. Because nitric oxide is spontaneously oxidized to both nitrite and nitrate, two analytic assays were used serially. Serum nitrite levels were initially determined with the Greiss reagent and subsequently analyzed with Escherichia coli nitrate reductase.

RESULTS

With the Greiss reagent alone the mean +/- SEM of serum nitrite level in 26 patients with preeclampsia was significantly decreased compared with 26 normotensive patients (3.46 +/- 1.43 mumol/L vs 4.65 +/- 0.85 mumol/L, p = 0.02). With the addition of the nitrate reductase enzyme of Escherichia coli the mean +/- SEM of serum nitrite level in 26 preeclamptic patients was again significantly decreased compared with 26 normotensive patients (20.04 +/- 1.25 mumol/L vs 27.38 +/- 2.23 mumol/L, p = 0.02). One patient with the syndrome of hemolysis, elevated liver enzymes, and low platelets demonstrated a concurrent decrease in serum nitrite over a 2-week period, emphasizing the relationship of nitric oxide to the pathophysiologic features of the syndrome.

CONCLUSIONS

Circulating levels of nitrite are decreased in patients with preeclampsia. These data support the concept that diminished nitric oxide synthesis contributes to the pathophysiologic changes seen in preeclampsia.

Fetal cardiac effects of oral ritodrine tocolysis

The beta-sympathomimetic oral tocolytic ritodrine can cause maternal tachycardia and hypotension, and may cross the placenta. A new echocardiographic technique has been developed to explore fetal and placental ritodrine effects. Values in 76 healthy historic controls were compared to 18 studies in 16 patients performed while receiving stable oral ritodrine therapy, measured both at baseline and 30 minutes after a dose. Data collected included maternal pulse and blood pressure (BP), fetal cerebral and umbilical Doppler waveforms, and fetal heart rate. A new index of fetal myocardial contractility, combined ventricular shortening fraction, was derived from two-dimensionally directed M-mode. Maternal pulse and BP, fetal heart rate and heart size, and all Doppler indices were normal, without demonstrable dose-response effects. In the control subjects, combined ventricular shortening fraction fell with increasing gestational age (combined ventricular shortening fraction = -0.27 estimated gestational age + 49; r = 0.27; P < or = 0.02; standard error of the estimate, 11%). However, combined ventricular shortening fraction in ritodrine patients was abnormally decreased in 72% of cases. The mean index in normal subjects was 43 +/- 5%, but in ritodrine patients it was only 31%. We conclude that a history of premature labor or oral ritodrine, or both, is associated with reduced shortening fraction. Since there was no change in placental resistance, cerebral hypoxia, fetal heart rate, or heart size (preload), then low shortening fraction may be due to increased fetal systemic vascular resistance (BP) or decreased myocardial contractility.

Synthesis of alpha 1-antichymotrypsin and alpha 1-antitrypsin by human trophoblast

alpha 1-Antichymotrypsin (alpha 1-ACHY) and alpha 1-antitrypsin (alpha 1-AT) are closely related glycoprotein protease inhibitors, present in plasma and other extracellular fluids, that neutralize proteases released by leukocytes in response to trauma and inflammatory stimuli. Both inhibitors are synthesized primarily by hepatocytes, although lower levels of synthesis by monocytes and breast and intestinal epithelial cells have been demonstrated. Recently, the immunohistochemical localization of alpha 1-AT and alpha 1-ACHY in intrauterine and extrauterine human trophoblastic tissue has been reported. In the present study, we have sought to determine whether human trophoblast is also able to synthesize alpha 1-AT and alpha 1-ACHY. Messenger RNA for both inhibitors was found by Northern blotting in chorionic villi obtained from first trimester and term placenta. Substantial differences in messenger levels for both inhibitors among individual placentas were noted. alpha 1-ACHY and alpha 1-AT messenger was also present in trophoblast cells in primary culture. Synthesis of alpha 1-AT and alpha 1-ACHY protein was demonstrated by SDS-PAGE after immunoprecipitation of [35S]-labeled alpha 1-AT and alpha 1-ACHY from conditioned media of trophoblast cells in culture metabolically labeled with [35S]-methionine. It is of some interest that the M(r) of the alpha 1-AT and alpha 1-ACHY secreted by trophoblast were 50,000 and 49,000, respectively, compared with 54,000 and 68,000 for these proteins in plasma (or secreted by HepG2 human hepatoma and MCF-7 human breast cancer cells).(ABSTRACT TRUNCATED AT 250 WORDS)

Use of esterase inhibitors and zone electrophoresis to define bacterial esterases in amniotic fluid

OBJECTIVE

The purpose of our study was to define further the role of bacterial esterases in amniotic fluid obtained from women with chorioamnionitis.

STUDY DESIGN

Amniotic fluid samples from 39 patients with chorioamnionitis were submitted for bacterial cultures and in vitro assay. Esterase inhibitors diisopropyl fluorophosphate and iodoacetic acid were added and the degree of inhibition calculated. These results were compared with the amniotic fluid culture results. Chi square analysis was performed to compare the results of the esterase assay and the inhibition assay between the uninfected and infected amniotic fluid samples.

RESULTS

Thirty-one patients had positive bacterial cultures, with 21 being infected with gram-negative organisms. All samples showed significant inhibition (range 55% to 82%) with diisopropyl fluorophosphate. There was partial inhibition with iodoacetic acid (range 10% to 30%) in the gram-negative samples but no inhibition in the gram-positive and uninfected samples. Six infected and two uninfected samples were analyzed by using zone electrophoresis with human plasma as a control. Minimal esterase motility was noted in the amniotic fluid samples as compared with that in plasma.

CONCLUSION

The esterases in amniotic fluid appeared to be of bacterial, not human, origin. Furthermore, different groups of bacteria appeared to produce different esterases in infected amniotic fluid.

Amniotic fluid index: correlation with amniotic fluid volume

We calculated the amniotic fluid indexes (AFIs) of 310 women on 459 occasions. Normative data were analyzed and compared with data in several high-risk groups. In the normal gestations there was a progressive increase in AFI with advancing gestation until 32 weeks, after which there was a decline. The mean AFIs in abnormal gestations varied with the clinical diagnoses. These values were compared to those obtained by assessing amniotic fluid volume (AFV), that is a pocket more than 2 cm. There were 51 patients with abnormal AFVs. Forty-two had decreased fluid, six also had decreased AFIs; nine had increased AFVs and five (all with diabetes) also had increased AFIs. Thus, AFIs in normal pregnancies showed an orderly pattern of change with gestational age, and there was no accurate correlation between AFI and AFV. Thus, using AFV alone may lead to false interpretations of amniotic fluid status.

Surgical treatment of incompetent cervix

A comparison of multiple factors in the surgical management of cervical incompetence was carried out in 114 procedures. Factors examined included training level of the operator, gestational age, cervical effacement and dilation at the time of operation, diagnostic evaluation, Shirodkar or McDonald procedure, year of the procedure, and tocolytic therapy. The endpoint for successful outcome was defined as 37 weeks or newborn weighing over 2500 gm rather than neonatal survival, thus differing from previous studies. All patients were delivered vaginally unless there was an obstetric indication for cesarean delivery. The most important determinants of a term birth in patients with incompetent cervix were operator experience and the use of a Shirodkar procedure.

Is plasma serine a marker for psychosis?

There is some disagreement in the literature concerning the use of plasma serine concentrations as a biological marker for psychoses including schizophrenia. The groups studying this phenomenon have used different methodologies, including gas chromatography and classical amino acid analysis. In the present study, using high pressure liquid chromatography to analyze plasma amino acids from schizophrenics and controls, we found no difference in plasma serine concentrations. None of the plasma amino acid concentrations that were measured differed significantly between schizophrenics and controls but the basic amino acids tended toward higher concentrations in schizophrenics.

Surgical management of drooling. Case report

Drooling occurs when excessive quantities of saliva dribble from the opened mouth. This distressing condition affects many mentally handicapped patients who are unable to effectively clear their normal salivary flow by swallowing. Any method employed for the control of drooling must still allow a sufficient volume of flow for mastication, deglutition and oral hygiene. Surgery is generally indicated for marked or severe cases of drooling and Wilkie's operation involving redirection of the parotid flow into the oropharynx is the most commonly performed surgical procedure. This operation may be combined with bilateral removal of the submandibular salivary glands if the problem is severe.

Pregnancy in patients with cerebrospinal fluid shunts: report of a series and review of the literature

Hydrocephalic women with cerebrospinal fluid shunts are now surviving to reproductive age. Twenty-one pregnancies in 18 patients with shunts, including 11 from the present series and 10 from previous series, were analyzed for neurological, obstetrical, and perinatal outcome. Fourteen women had preexisting shunts, and 4 had the onset of symptomatic hydrocephalus and the placement of shunts during pregnancy. Neurological complications occurred in 13 of 17 (76%) pregnancies in patients with preexisting shunts, including symptoms of increased intracranial pressure (ICP) in 10 of 17 (59%) pregnancies, exacerbation of seizure disorder in 2 of 17 (12%) pregnancies, and severe headaches without increased ICD in 1 patient. In 7 of 11 (66%) of the symptomatic patients, symptoms spontaneously resolved postpartum. Four of 17 (23%) of these pregnancies were associated with shunt obstruction requiring antepartum or postpartum surgery. Four patients had a primary shunt placement, and one had a shunt revision during pregnancy without complications. There were no unusual obstetrical or perinatal complications in the series. The clinical management of pregnant patients with hydrocephalus should include preconception counseling and magnetic resonance imaging, as well as the use of serial antenatal magnetic resonance images, ICP monitoring, or the judicious use of radioisotope studies of shunt patency if signs of increased ICP appear. A cesarean section is recommended for the delivery of the neurologically unstable patient. For asymptomatic mothers, a vaginal delivery with a shortened second stage and prophylactic antibiotics are advised.

Variable decelerations in reactive nonstress tests with decreased amniotic fluid index predict fetal compromise

A total of 3158 patients at greater than or equal to 34 weeks' gestation undergoing nonstress tests and amniotic fluid index determinations were divided into six groups according to the amniotic fluid index and the nature of the decelerations. Fetuses with antepartum decelerations had statistically significantly increased incidences of intrapartum decelerations and operative deliveries because of intrapartum "distress," regardless of the amniotic fluid index. They also had significantly increased rates of neonatal acidosis and low Apgar scores when there were "severe" decelerations and an amniotic fluid index less than 5 in the antepartum period. Thus spontaneous decelerations in reactive nonstress tests with an amniotic fluid index less than 5 may predict fetal compromise.

Acid-base differences in preterm and term twin pregnancy

A prospective study was undertaken which examined 179 sets of twins, 68 premature (less than 36 weeks of gestation) and 111 term. The purpose of this study was to assess differences in the acid-base status between twins related to gestational age, birth order and the time interval between twin births. Although the twin blood-gas data is within the range considered normal, statistically significant differences favoring the first-born were noted for both preterm and term twins. These differences do not depend on gestational age, route of delivery or presentation, and become evident when the interval between twin births exceeds one minute. We postulate that after delivery of the first twin, the reduced uterine size causes a decrease in the intervillous blood flow and consequently a reduction in the respiratory exchange between the second fetus, still in utero, and its placenta.

Relationship between antepartum cocaine abuse, abnormal umbilical artery Doppler velocimetry, and placental abruption

We performed serial umbilical artery Doppler flow velocimetry studies on 314 women and grouped them according to history of antepartum cocaine abuse, placental abruption with antepartum cocaine abuse, preterm labor with antepartum cocaine abuse, preterm labor without antepartum cocaine abuse, and controls without preterm labor or antepartum cocaine abuse. Analyses excluded twin gestation, diabetes, and hypertension. The overall incidence of deliveries at or before 36 weeks was 28% (31 of 112). Thirteen (12%) of the infants were small for gestational age (SGA) and 33 (29%) were low birth weight (LBW). Almost all subjects with a history of cocaine abuse had normal systolic-diastolic ratios (S/Ds). All patients with abruption had abnormal S/Ds, as did 14 of 64 subjects who had preterm labor and a history of cocaine abuse. No abnormal S/Ds were found in the women with preterm labor or in controls. Among cocaine-abusing women, there was a significant correlation between placental abruption and abnormal S/Ds (P less than .05) and between abnormal S/Ds and the incidence of preterm birth and SGA and LBW infants.

A large dermoid cyst of the neck. Case report

An elderly patient presented with a large asymptomatic submental swelling which had been present for about fifteen years. The clinical diagnosis was a dermoid cyst and the lesion was removed in toto. Histological examination confirmed the clinical diagnosis. Unless such lesions are very large and cause displacement of the tongue, there is usually no associated dyspnoea, dysphagia or dysphonia.

Pancreatic enzyme activity in pregnancy

Serum amylase activity and the amylase:creatinine clearance ratio (Cam:Ccr%) are two of the most commonly used indicators for the diagnosis of pancreatitis. However, published data on the effect of pregnancy on these indicators are conflicting. Furthermore, there are no published data on the effect of pregnancy on serum lipase activity, which is considered one of the most sensitive and specific indicators of pancreatitis. A study was undertaken to determine the effect of pregnancy and gestational age on serum amylase, serum lipase and Cam:Ccr% levels and to establish a baseline of normal values for use in the diagnosis of pancreatitis in pregnant women. Serum amylase, serum lipase and Cam:Ccr% levels were determined on a sample population consisting of 175 pregnant women with gestational ages ranging from 5 to 40 weeks and on a control group of 44 reproductive-age, nonpregnant women. The study results indicated that there is no significant difference in serum amylase, serum lipase and Cam:Ccr% levels between pregnant and nonpregnant women. Cam:Ccr% showed a small but statistically significant increase in the third trimester of pregnancy.

Performance of cesarean section using absorbable staples

Although stapling techniques have gained wide acceptance in general surgery, they are still not commonly used in obstetrics. U.S. Surgical Corporation has introduced a stapling device suitable for use in cesarean sections. The copolymer staples (a blend of polylactic and polyglycolic acids) maintain their tensile strength until healing occurs and absorb without producing granulation tissue. The benefits include minimal trauma to tissue and reduced operating time, blood loss and postoperative morbidity. From July 1988 to February 1989, all patients undergoing low transverse cervical cesarean sections were randomized to either group 1 with the uterine incision performed in a routine manner or group 2 with the uterine incision cut and stapled using the Stapler. The preoperative management, intraoperative technique and postoperative surveillance were similar for both groups. The uterine incision was assessed by pelvic sonography during the postpartum period. Statistical analysis was performed using Fisher's exact test and chi-square analysis. Both groups were comparable for age, race, parity, gestational age and primary diagnosis. The length of the operative procedure was significantly shorter (p less than 0.05) in the stapled group. These patients also had a statistically significantly decreased incidence of uterine incisions and lacerations. All other parameters were not significantly different in the two groups. The stapled uterine incisions were visible by ultrasonography in more patients in the stapled group throughout the postpartum period than in the sutured group. Thus, stapling of the uterine incision was an acceptable alternative to traditional suturing techniques and it was possible to visualize clearly these incisions during the postpartum period.

In vitro inhibition of esterase activity in amniotic fluid: comparison with bacterial cultures

Assessment of leukocyte esterase activity in amniotic fluid for the rapid and reliable diagnosis of chorioamnionitis has been demonstrated previously. We compared in vitro inhibition of esterase activity in amniotic fluid with bacterial cultures to identify the origins of the specific esterases released by the infecting organisms. One hundred forty-one samples were tested (90 uninfected, 51 infected). Each sample was evaluated for Gram stain, cultures, and an in vitro esterase assay followed by ebelactone inhibition. Forty-two patients had positive amniotic fluid cultures. Ebelactone produced varying degrees of inhibition of esterase activity (range, 20% to 60%) in the uninfected samples and in those infected with gram-negative organisms. There was no inhibition in the samples infected with gram-positive organisms. Thus different groups of bacteria may elicit the production of different and specific esterases in infected amniotic fluid, as shown by the differences in in vitro inhibition.

The Shirodkar operation: a reappraisal

Sixty-six cerclages were performed by one surgeon in 46 patients with documented cervical incompetence. The mean operative blood loss was 25 ml, and the mean operating time was 18 minutes with no postoperative morbidity. Fifty-five of the pregnancies were carried for at least 37 weeks, eight were delivered before 37 weeks, and three are continuing. Six of the eight preterm deliveries were a result of factors unrelated to cervical incompetence. The two remaining preterm births were probably also unrelated because one occurred 8 days after emergent cerclage placement and the other occurred 12 weeks after the procedure, both as a result of premature rupture of membranes. There were no cesarean deliveries related to the Shirodkar suture. The efficacy of the procedure was demonstrated by a corrected perinatal survival rate of 100% and term delivery of 88%. (Since this article was written all three of the undelivered patients were delivered of infants after 37 weeks' gestation for a term delivery rate of 88% with 100% neonatal survival.

Aneurysm of the vein of Galen: a new cause for Ballantyne syndrome

Ballantyne syndrome is a condition of multiple causes and is characterized by maternal, placental, and fetal edema. We describe the first case of Ballantyne syndrome in a patient whose fetus had ultrasonographic demonstration of an aneurysm of Galen's vein.

Leukocyte esterase activity in amniotic fluid: normal values during pregnancy

Chorioamnionitis during pregnancy is a common diagnostic dilemma for the obstetrician. Fast and accurate diagnosis poses the most significant problem. Since leukocytes are known to be released in response to infections, examination of amniotic fluid for their presence is an important part of the evaluation for chorioamnionitis. These neutrophils contain several esterases that are not present in serum, urine, or vaginal secretions. The esterases are not influenced by bacteria or by commonly used drugs. We have previously described the reliability of leukocyte esterase (LE) activity for the detection of chorioamnionitis in term pregnancies uncomplicated by other diseases. A prospective study was performed to assess the presence or absence of LE activity to establish normal values in amniotic fluid at various gestational ages prior to term before its use as a possible predictor for chorioamnionitis. Sterile amniotic fluid specimens were obtained from 13 patients undergoing second trimester genetic amniocentesis (with gestational ages varying from 15 to 19 weeks) and from 11 patients with a wide variety of medical problems, undergoing amniocentesis for Rh sensitization or lung maturation studies (with gestational ages ranging from 25 to 27 weeks). All patients with ruptured membranes or preterm labor were excluded. Each amniotic fluid sample was divided into two parts, one of which was transported to the laboratory for aerobic and anaerobic cultures and the other used for LE activity detection as measured by dipstick. The LE results were retrospectively compared with the results of the cultures. LE activity was always found to be negative when the culture results were negative. negative.(ABSTRACT TRUNCATED AT 250 WORDS)

Successful pregnancy with isolated herpes simplex virus encephalitis: case report and review of the literature

Isolated herpes simplex virus encephalitis in pregnancy is a rare illness with an elusive diagnosis. We describe the second patient to survive this disease and the first to have no sequelae, because of prompt diagnosis and treatment with acyclovir.

Esterase activity in second- and third-trimester amniotic fluid: an indicator of chorioamnionitis

Accurate and rapid diagnosis of chorioamnionitis poses a major diagnostic dilemma. We previously reported that leukocyte esterase activity in amniotic fluid, as measured by dipstick assay, could be used as an aid in the diagnosis of chorioamnionitis. This study examines the effectiveness of an in vitro spectrophotometric assay of esterase activity in amniotic fluid. We define baseline levels of esterase activity in uninfected amniotic fluid and demonstrate a quantitative increase when infection is present. Fifty-seven amniotic fluid samples obtained at second- and third-trimester amniocenteses were divided into three parts, one for culture and two for a comparison of esterase activities by the dipstick and spectrophotometric methods. In this study, the spectrophotometric assay, because of its higher specificity and sensitivity in the determination of elevated esterase activity, was shown to be more reliable for predicting chorioamnionitis than either the dipstick or culture method.

Congenital hereditary fructose intolerance and pregnancy

Congenital hereditary fructose intolerance is associated with the inability to tolerate fructose and carbohydrates, which are converted into fructose. We describe management of a pregnancy complicated by this disease in the mother and its implications for the neonate.

Diagnosis of adrenal ganglioneuroma in pregnancy with magnetic resonance imaging and ultrasonography. A case report

A right adrenal gland mass was found during sonographic examination of the right upper quadrant during a workup for hyperemesis gravidarum. Magnetic resonance imaging was used to clarify the origin of the mass. The tumor was nonfunctional. Because of the possibility of a malignancy, the patient underwent a successful second-trimester exploratory laparatomy with right adrenalectomy. Pathology demonstrated a benign ganglioneuroma.