Diversity of microorganisms within rock varnish in the Whipple Mountains, California.

Rock varnish from Arizona's Whipple Mountains harbors a microbial community containing about 10(8) microorganisms g(-1) of varnish. Analyses of varnish phospholipid fatty acids and rRNA gene libraries reveal a community comprised of mostly Proteobacteria but also including Actinobacteria, eukaryota, and a few members of the Archaea. Rock varnish represents a significant niche for microbial colonization.

Application of three-dimensional ultrasonography in the evaluation of the fetal heart.

The objectives of this study were to determine whether three-dimensional ultrasonography can provide more cardiac views than two-dimensional ultrasonography and to develop a standard technique. Eighteen women, 16 to 26 weeks' gestation, were scanned with two-dimensional ultrasonography for 10 minutes or less to obtain fetal heart views. Three-dimensional ultrasonography was used (< or =10 minutes) to obtain up to 4 acquisitions of the fetal heart: 4-chamber view, left parasagittal, transverse, and longitudinal nonstandard. Views were later extracted from saved volume data, comparing the yields of two- and three-dimensional ultrasonography. The 4-chamber view was obtained in 15 (93%) of 16 cases on both two- and three-dimensional ultrasonography. On two-dimensional ultrasonography, the left outflow tract was obtained in 68% of the cases; on three-dimensional ultrasonography, the left outflow tract was obtained in 46% from the 4-chamber view acquisition and in 100% from the left parasagittal acquisition. On two-dimensional ultrasonography, the right outflow tract was obtained in 68% of the cases; on three-dimensional ultrasonography, the right outflow tract was obtained in 86% from the 4-chamber view acquisition and in 71% from the left parasagittal acquisition. Aortic and ductal arches were obtained in 12% and 18%, respectively, on two-dimensional ultrasonography. On three-dimensional ultrasonography the aortic and ductal arches were obtained in 66% and 86%, respectively, from the 4-chamber view acquisition and in 57% and 71%, respectively, from the left parasagittal acquisition. Three-dimensional ultrasonography permitted a greater number of cardiac views to be extracted from volume data than did two-dimensional ultrasonography.

Fabrication of specimens of metamorphic magnetite crystals for field ion microscopy and atom probe microanalysis.

Field ion specimens have been successfully fabricated from samples of metamorphic magnetite crystals (Fe3O4) extracted from a polymetamorphosed, granulite-facies marble with the use of a focused ion beam. These magnetite crystals contain nanometer-scale, disk-shaped inclusions making this magnetite particularly attractive for investigating the capabilities of atom probe field ion microscopy (APFIM) for geological materials. Field ion microscope images of these magnetite crystals were obtained in which the observed size and morphology of the precipitates agree with previous results. Samples were analyzed in the energy compensated optical position-sensitive atom probe. Mass spectra were obtained in which peaks for singly ionized 16O, 56Fe and 56FeO and doubly ionized 54Fe, 56Fe and 57Fe peaks were fully resolved. Manganese and aluminum were observed in a limited analysis of a precipitate in an energy compensated position sensitive atom probe.

Prediction of preterm birth by second trimester cervical sonography in twin pregnancies.

OBJECTIVES: To determine the predictive value of sonographic cervical length and of funneling for spontaneous preterm delivery (PTD) in twin pregnancies under 26 weeks' gestation. METHODS: Women with twin pregnancies were studied prospectively with transvaginal or translabial ultrasound of the cervix from 18 to 26 weeks' gestation. Exclusion criteria were: signs of preterm labor, prophylactic cervical cerclage, placenta previa, or severe congenital fetal anomaly. The primary outcome was spontaneous preterm birth at < 35 weeks' gestation. RESULTS: Sixty-five twin pregnancies were analyzed, of which 23% (15/65) delivered preterm. Cervical ultrasound examination was performed by 22 weeks' gestation in 75% and by 24 weeks' gestation in 91% of women. Cervical length < or = 25 mm and < or = 30 mm was associated with sensitivities of 27% and 53%, respectively, and with 67% and 62% rates of PTD, respectively (R.R. 4.6, C.I. 2.0-10.3 and R.R. 3.6, C.I. 1.6-7.8, respectively). A cervical length > 35 mm was associated with only a 4% rate of PTD (R.R 0.13; C.I. 0.02-0.93). Of 10 women (15%) with any cervical funneling, 70% delivered preterm, all under 32 weeks' gestation. By logistic regression analysis, both short cervix < or = 30 mm and any funneling were strongly predictive of PTD. CONCLUSIONS: Both cervical length < or = 30 mm and cervical funneling in twin pregnancies under 26 weeks' gestation are independently and strongly associated with high risk for preterm birth. A long cervix, of length > 35 mm, is associated with very low risk (4%) for preterm birth.

Three-dimensional multiplanar ultrasound for fetal gender assignment: value of the mid-sagittal plane.

OBJECTIVE: To evaluate the feasibility and accuracy of fetal gender assignment from three-dimensional ultrasound (3D US) data at 10-24 weeks' gestation. METHODS: Three-dimensional ultrasound volume data on 47 fetuses were reviewed and divided into groups: 10-14, 15-18, and 19-24 weeks. Fetal genitalia were studied in axial and sagittal planes for gender assignment, using published criteria. The most valuable plane for assignment was noted. Gender assignment was compared with gender at birth. RESULTS: Gender assignment was possible in 44 of 47 fetuses; 25 assigned male and 19 female. Between 10 and 14 weeks the mid-sagittal plane alone was diagnostic for all fetuses. Accuracy of assignment between 11 and 14 weeks was 100%. Between 15 and 18 and 19 to 24 weeks, male assignment was 100% accurate. Female assignment was 100% accurate between 15 and 18 weeks. Accuracy decreased to 60% in the 19 to 24 week group, however, in two of the five cases in which gender was wrongly assigned to be male, the assignment was prospectively considered doubtful due to poor resolution of volume data. Excluding these two cases, accuracy for female assignment in the 19-24 week group was 100%. CONCLUSION: Using 3D US, gender assignment was possible in 44 of 47 of fetuses, as early as 11 weeks' gestation. In early gestation, 11-14 weeks, accuracy of male and female gender assignment was 100%.

Three-dimensional multiplanar transvaginal ultrasound of the cervix in pregnancy.

OBJECTIVES: To develop a standard technique for using three-dimensional ultrasound (3D US) to study and evaluate the cervix in pregnant women at high risk for premature delivery, comparing the findings on 3D US with those on conventional two-dimensional ultrasound (2D US). STUDY DESIGN: Twenty-one pregnant women at high risk for premature delivery had a total of 37 transvaginal 2D and 3D US examinations of the cervix between 11 and 32 weeks' gestation. A 3D US vaginal probe (5.0-8.0 MHz, Voluson 530D, Medison, Pleasanton, CA, USA) was used. Measurements made from the 2D and 3D US were compared. RESULTS: Of the 37 cervical length measurements in 3D US sagittal plane, seven were shorter and three were longer than on 2D US (varying by 5-15 mm) indicating that the true mid-sagittal plane was not obtained in ten (27%) of the 37 2D US examinations. Of 21 examinations showing funneling, funneling was seen on both 2D and 3D US in 15, but was seen only on 3D US in six. There was a significant (P < 0.05) difference between funnel width as measured in the coronal 3D plane versus 2D US, as well as between funnel width in the coronal 3D US plane versus sagittal 3D US plane (P < 0.05). The cerclage was seen in its entirety in nine of 10 examinations; the 3D US axial plane was most valuable for imaging the cerclage. CONCLUSIONS: 3D US appears to offer a more complete assessment of the cervix than 2D US. Multiplanar correlation shows that the standard 2D US sagittal view may under- or over-estimate cervical length. Our preliminary data suggest that 3D US has the potential to improve our understanding of cervical morphology.

Diagnosis of conjoined twins at 10 weeks using three-dimensional ultrasound: a case report.

A case report is presented of the prenatal diagnosis of conjoined twins at 10 weeks and 2 days' gestation using three-dimensional ultrasound (3D US). The multiplanar display coupled with 3D US surface rendering clearly confirmed the presence of craniopagus. The twins were facing in opposite directions with the left occipital region of one embryo fused with the left parietal-temporal region of the other. Additional multiplanar analysis above the level of the biparietal diameter demonstrated brain sharing.

Placenta accreta: comparison of cases managed with and without pelvic artery balloon catheters.

OBJECTIVE: To describe our experience with the use of prophylactic pelvic artery balloon catheters in cases of placenta accreta diagnosed by antenatal ultrasound and to compare these cases with contemporary controls. METHODS: In this prospective study, all patients seen at our institution between January 1994 and August 1997 with the antenatal sonographic diagnosis of placenta accreta were offered prophylactic preoperative pelvic artery balloon catheterization. Patients who were delivered by cesarean hysterectomy for unsuspected placenta accreta in our institution during the same time interval served as controls. Five patients with the sonographic diagnosis of placenta accreta underwent prophylactic pelvic artery balloon catheterization. Surgical outcomes in patients who received balloon catheters were compared with those managed without them. Statistical analysis was performed using the Mann-Whitney U test. RESULTS: Five patients with placenta accreta or one of its variants were correctly identified with antenatal ultrasonography. Of the five patients who underwent pelvic artery balloon catheterization, all had placenta accreta and four required cesarean hysterectomy. The mean estimated blood loss, transfusion requirement, and length of hospitalization in patients undergoing hysterectomy managed with and without the balloon catheters was not different (P > 0.06). CONCLUSIONS: Antenatal sonographic diagnosis of placenta accreta enables preoperative planning. In our experience, use of pelvic artery balloon occlusion catheters in patients requiring a cesarean hysterectomy for placenta accreta did not improve surgical outcomes compared with patients managed without them. These preliminary findings are based on a small number of patients; therefore, further investigation is needed.

Cervical ultrasonography compared with manual examination as a predictor of preterm delivery.

OBJECTIVE: Our purpose was to compare the accuracy of ultrasonographic and manual cervical examinations for the prediction of preterm delivery. STUDY DESIGN: One hundred two singleton pregnancies at high risk for preterm delivery were followed up prospectively from 14 to 30 weeks with both serial cervical ultrasonography measurements and manual examinations of the length of the cervix. The primary outcome studied was preterm (< 35 weeks) delivery. RESULTS: Excluding six induced preterm deliveries, 96 pregnancies were analyzed. The mean cervical length measured by ultrasonography was 20.6 mm in pregnancies delivered preterm (n = 17) and 31.3 mm in pregnancies delivered at term (n = 79) (p = 0.003); the mean cervical lengths measured by manual examination were 16.1 mm and 18.6 mm in the same preterm and term pregnancies, respectively (not significant). The sixteenth- and twentieth-week ultrasonographic cervical lengths predicted preterm delivery most accurately (p < 0.0005). The 25th percentiles of ultrasonographic (25 mm) and manual (16 mm) cervical lengths showed relative risks for preterm delivery of 4.8 (95% confidence interval 2.1 to 11.1, p = 0.0004) and 2.0 (95% confidence interval 0.5 to 4.7, p = 0.1), respectively; sensitivity, specificity, and positive and negative predictive values were 59%, 85%, 45%, 91%, and 41%, 77%, 28%, and 86%, respectively. CONCLUSION: Cervical length measured by ultrasonography is a better predictor of preterm delivery than is cervical length measured by manual examination. Cervical ultrasonography in patients at high risk for preterm birth seems to be most predictive of preterm delivery when it is performed between 14 and 22 weeks' gestation.

Cervical funneling: sonographic criteria predictive of preterm delivery.

Our objective was to establish sonographic criteria that are predictive of preterm delivery in patients with internal os dilatation (funneling). The study population consisted of patients with cervical funneling identified on translabial or transvaginal ultrasound examination. Funnel length, functional length, percentage funneling and funnel width were evaluated for their predictive values for preterm delivery. In the 43 patients who met the study criteria, funneling was detected at a mean gestational age of 21.4 weeks (range 16-28). Twenty-three of 31 patients (74%), manually examined immediately following the ultrasound examination, had a closed cervix. Preterm delivery occurred in 42% of patients. Funnel length of > or = 16 mm, functional length of < or = 20 mm, funneling of > or = 40% and funnel width of > or = 14 mm correlated significantly with preterm delivery. Patients with funneling of < 25%, 25-50% and > 50% had preterm delivery rates of 17%, 29% and 79%, respectively.

Effects of reactive oxygen and nitrogen species induced by ammonium dinitramide decomposition in aqueous solutions of deoxyribose nucleic acid.

Ammonium dinitramide (ADN), a potential rocket fuel, decomposes in water forming NO2. The chemistry of this ADN-released NO2 in oxygenated biological systems is complex both in the number of potential chemical species and in the number of parallel and consecutive reactions that can theoretically occur. High-pressure liquid chromatography (HPLC) studies revealed ADN fragmented deoxyribose nucleic acid (DNA). Damage to DNA standard solutions was caused by at least two major pathways, one arising from reactions of NO2 with oxygen and one arising from a reaction with superoxide (O2-.). The radical species generated when ADN is incubated with standard solutions of DNA, pH 7.5, in the presence of the spin trap agent n-tert-butyl-alpha-nitrone (PBN) was compared with the PBN-radical adducts generated in the presence of ADN and O2-. or of ADN and hydrogen peroxide (H2O2). The ADN-induced PBN radical adducts increased linearly over the 90-minute study period. The values of peak intensity in the presence of O2-. and in the presence of H2O2, were 828% and 7.08%, respectively, of the ADN-induced radicals alone. The synergistic effect of ADN with O2- may provide an understanding of the sensitivity of the rat blastocyst to aDN at the preimplantation stage of development and the lack of toxicity in in vivo studies in tissues high in catalase.

Sensitivity and specificity of carpal tunnel syndrome signs.

The sensitivity and specificity of six carpal tunnel syndrome (CTS) signs were determined by evaluating 143 subjects (228 hands) with symptoms of CTS. Immediately after performing the six physical examination tests, standard nerve conduction studies were performed on all 228 hands to determine the presence or absence of CTS. CTS was present in 142 hands and absent in 86 hands. The signs were not very sensitive (23-69%), but were fairly specific (66-87%) for CTS. A square-shaped wrist and abductor pollicis brevis weakness were the most sensitive signs (69 and 66%, respectively), and are recommended as part of the examination of CTS. Median nerve hypesthesia and the Phalen sign both have fair sensitivity (51%) but good specificity (85 and 76%, respectively). The median nerve compression sign and the Hoffmann-Tinel sign both have poor sensitivity (28 and 23%, respectively), and thus are less helpful in evaluating subjects with suspected CTS.

Bilateral musculocutaneous nerve palsy. A case report.

A case of bilateral, isolated, proximal musculocutaneous nerve palsy is reported. Initial physical and electromyographic examinations demonstrated complete denervation of the biceps brachii, brachialis, and coracobrachialis muscles bilaterally. Nerve conduction studies of the musculocutaneous nerves initially revealed no evoked potentials. The patient underwent resection with end-to-end anastomosis on the left and neurolysis without resection on the right. Significant functional recovery was noted bilaterally but was more rapid and complete on the side that underwent neurolysis without resection.

Bradykinin receptor antagonists containing N-substituted amino acids: in vitro and in vivo B(2) and B(1) receptor antagonist activity.

We report a systematic probing of the structural requirements of the bradykinin (BK) type 2 (B(2)) receptor for antagonist activity by incorporating N-alkyl-amino acid residues at positions 7 and 8 of a potent antagonist sequence. Compound 1 (D-Arg(0)-Arg(1)-Pro(2)-Hyp(3)-Gly(4)-Thi(5)-Ser(6)-D-Tic(7)-N-Chg (8)-Arg(9), CP-0597)(1,2) is a potent (pA(2) = 9.3, rat uterus; pK(i) = 9.62, binding, human receptor clone) B(2) receptor antagonist devoid of in vitro B(1) antagonist activity (rabbit aorta). Compound 1 exhibits high potency (ED(50) = 29.2 pmol/kg/min, iv, rabbit) and duration of action when tested in models for in vivo B(2) antagonist activity. Although devoid of activity in a classic B(1) isolated tissue assay, B(1) antagonist activity for 1 was demonstrated in vivo, in a LPS-treated, inducible BK(1) receptor rabbit blood pressure model (ED(50) = 1.7 nmol/kg/min). D-Arg(0) of 1 can be formally replaced by an achiral arginine surrogate, without significant loss in antagonist potency on rat uterus (compound 11, B(2) pA(2) = 9.1). Antagonist 13 (Hyp(2), Nchg(8)), pK(i) = 10.2, and agonist 4 (N-methylcyclohexyl-Gly(8)), pK(i) = 10.1, also exhibited substantial binding to guinea pig ileum membrane receptors as well as a human B(2) receptor clone. Very minor structural changes in the N-alkyl amino acid residues in positions 7 and 8 can modify the activity of this class of compounds from being extremely potent antagonists to tight binding partial or full agonists. These studies have resulted in a series of compounds containing inexpensive amino acid residues but which produce broad spectrum BK receptor blocking potency and exceptional in vivo duration of action.

Congenital diaphragmatic hernia: prognosis and prenatal detection.

Fifty consecutive cases of isolated congenital diaphragmatic hernia were reviewed for prenatal ultrasound and neonatal physical findings. These were compared to survival and the need for extracorporeal membrane oxygenation (ECMO). No prenatal findings predicted survival or the need for ECMO. In left-sided hernias, the presence of the liver in the chest predicted (p = 0.02) the requirement for ECMO. In a cohort of 13 prenatally diagnosed inborn cases, the ultrasound triad of polyhydramnios, mediastinal shift and intrathoracic stomach predicted the presence of liver in the chest (p < 0.03).

Correlation of fetal heart rate decelerations following acoustic stimulation with perinatal outcome.

This was a retrospective study of acoustic stimulation response and perinatal outcome of 688 fetuses undergoing nonstress testing. Acoustic stimulation was performed within 7 days of delivery, and responses were classified based on the presence of an acceleration, deceleration, or both. Responses were correlated with perinatal outcome. Abnormal outcome was defined as: cesarean section for nonreassuring fetal heart rate patterns with an acidotic umbilical artery cord gas; delivery at less than 32 weeks for nonreassuring antenatal fetal testing; meconium aspiration syndrome or mechanical ventilation at 36 weeks or greater; neonatal seizures; 5-minute Apgar score less than 7; and stillbirth. Fetuses who demonstrated deceleration responses were significantly more likely to have abnormal perinatal outcomes when compared with those with acceleration responses (p < 0.001). Although combination acceleration-deceleration responses were more often associated with abnormal perinatal outcome when compared with pure acceleration responses, differences were not significant. A deceleration response following acoustic stimulation is associated with increased risk for adverse perinatal outcome and may merit further evaluation.

Cervical range of motion in the elderly.

This study was conducted to establish normative cervical range of motion values for the elderly and to compare those values to standard young adult cervical range of motion values. Differences in range of motion between men and women were also assessed. A gravity goniometer was used to measure six cervical motions in 42 subjects aged 70 to 90 years and 31 subjects aged 20 to 30 years. The elderly group had significantly less motion than the younger group for all six motions measured (p < .001). A comparison of the mean range of motion values between the two groups found that the elderly group had approximately 12% less flexion, 32% less extension, 22% less lateral flexion, and 25% less rotation. The elderly group also had a wider variation of cervical range of motion values as compared to the younger group. Women had greater cervical range of motion values than men in both age groups.