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The nova super-remnant (NSR) surrounding M31N 2008-12a (12a), the annually erupting recurrent nova (RN), is the only known example of this phenomenon. As this structure has grown as a result of frequent eruptions from 12a, we might expect to see NSRs around other RNe; this would confirm the RN--NSR association and strengthen the connection between novae and type Ia supernovae (SN Ia) as NSRs centered on SN Ia provide a lasting, unequivocal signpost to the single degenerate progenitor type of that explosion. The only previous NSR simulation used identical eruptions from a static white dwarf (WD). In this Paper, we simulate the growth of NSRs alongside the natural growth/erosion of the central WD, within a range of environments, accretion rates, WD temperatures, and initial WD masses. The subsequent evolving eruptions create dynamic NSRs tens of parsecs in radius comprising a low-density cavity, bordered by a hot ejecta pile-up region, and surrounded by a cool high-density, thin, shell. Higher density environments restrict NSR size, as do higher accretion rates, whereas the WD temperature and initial mass have less impact. NSRs form around growing or eroding WDs, indicating that NSRs also exist around old novae with low-mass WDs. Observables such as X-ray and H$\alpha$ emission from the modelled NSRs are derived to aid searches for more examples; only NSRs around high accretion rate novae will currently be observable. The observed properties of the 12a NSR can be reproduced when considering both the dynamically grown NSR and photoionisation by the nova system., Comment: 20 pages, 20 figures; Accepted for publication in Monthly Notices of the Royal Astronomical Society. For the animation in Figure 4, see https://www.dropbox.com/s/7a6zbu4eyv6kv8x/coolRun1.mp4?dl=0

The recurrent nova and symbiotic binary RS Oph erupted again in August 2021 for its eighth known outburst. As part of a multi-epoch and frequency campaign, we observed RS Oph 34 days after the outburst at 5 GHz with the European VLBI Network (EVN). The radio image is elongated over the east-west direction for a total extension of about 90 mas (or about 240 AU at the Gaia DR3 distance d=2.68 [-0.15/+0.17] kpc), and shows a bright and compact central component coincident with the Gaia astrometric position, and two lobes east and west of it, expanding perpendicular to the orbital plane. By comparing with the evolution of emission-line profiles on optical spectra, we found the leading edge of the lobes to be expanding at 7550 km/s, and i=54 deg as the orbital inclination of the binary. The 2021 radio structure is remarkably similar to that observed following the 2006 eruption. The obscuring role of the density enhancement on the orbital plane (DEOP) is discussed in connection to the time-dependent visibility of the receding lobe in the background to the DEOP, and the origin of the triple-peaked profiles is traced to the ring structure formed by the nova ejecta impacting the DEOP., A&A Letter to the Editor, in press

On 2021 August 8, the recurrent nova RS Ophiuchi erupted again, after an interval of 15.5 yr. Regular monitoring by the Neil Gehrels Swift Observatory began promptly, on August 9.9 (0.37 day after the optical peak), and continued until the source passed behind the Sun at the start of November, 86 days later. Observations then restarted on day 197, once RS Oph emerged from the Sun constraint. This makes RS Oph the first Galactic recurrent nova to have been monitored by Swift throughout two eruptions. Here we investigate the extensive X-ray datasets from 2006 and 2021, as well as the more limited data collected by EXOSAT in 1985. The hard X-rays arising from shock interactions between the nova ejecta and red giant wind are similar following the last two eruptions. In contrast, the early super-soft source (SSS) in 2021 was both less variable and significantly fainter than in 2006. However, 0.3-1 keV light-curves from 2021 reveal a 35 s quasi-periodic oscillation consistent in frequency with the 2006 data. The Swift X-ray spectra from 2021 are featureless, with the soft emission typically being well parametrized by a simple blackbody, while the 2006 spectra showed much stronger evidence for superimposed ionized absorption edges. Considering the data after day 60 following each eruption, during the supersoft phase the 2021 spectra are hotter, with smaller effective radii and lower wind absorption, leading to an apparently reduced bolometric luminosity. We explore possible explanations for the gross differences in observed SSS behaviour between the 2006 and 2021 outbursts., 21 pages, 16 colour figures, accepted for publication in MNRAS. Table 1 in full is included as an ancillary PDF (will be supplementary online material when published by MNRAS)

To analyze the records of the pregnancies of 2283 Australian women with epilepsy in the Australian Register of Antiepileptic Drugs in Pregnancy database to identify neurological factors relevant to the Cesarean sections carried out in these pregnancies.The Cesarean section rate in Australian women overall increased by an average of 0.59% annually over 20 years, from 26.0% to its calculated 2020 value of 37.3%. For the operations in women with epilepsy, the corresponding figures were 0.71% annually, and 34.4% and 48.7%. The average annual rate of increase for pre-labor operations was 0.89% to a 2020 value of 39.1%, the annual rate for operations during labor showing no statistically significant change. Multivariate regression analysis identified a number of characteristics of women with epilepsy that were statistically significantly associated with an increased likelihood of Cesarean section, but of these only seizures continuing to occur in the third trimester and having chronic illness, in particular migraine, were neurological ones. In 70 migraine-affected women, the Cesarean section rate was 51.4%, compared with 39% in the remaining pregnancies (P 0.05).Having seizures in the final trimester of pregnancy and having chronic neurological illness, especially migraine, favored Cesarean section being carried out in Australian women with epilepsy, but did not adequately account for the increasing rates of occurrence of the operation over the past 20 years.

Here we report that the most rapidly recurring nova, M31N 2008-12a, which erupts annually, is surrounded by a "nova super-remnant" which demonstrates that M31N 2008-12a has erupted with high frequency for millions of years., Comment: 30 pages, 8 figures

Background Anesthetic induction and maintenance with propofol are associated with decreased blood pressure that is, in part, due to decreased peripheral resistance. Several possible mechanisms whereby propofol could reduce peripheral resistance include a direct action of propofol on vascular smooth muscle, an inhibition of sympathetic activity to the vasculature, or both. This study examined these two possibilities in humans by measuring the forearm vascular responses to infusions of propofol into the brachial artery (study 1) and by determining the forearm arterial and venous responses to systemic (intravenous) infusions of propofol after sympathetic denervation of the forearm by stellate blockade (study 2). Methods Bilateral forearm venous occlusion plethysmography was used to examine forearm vascular resistance (FVR) and forearm vein compliance (FVC). Study 1 used infusion of intralipid (time control) and propofol at rates between 83 and 664 micrograms/min into the brachial artery of 11 conscious persons and compared responses to arterial infusions of sodium nitroprusside (SNP) at 0.3, 3.0, and 10 micrograms/min. Venous blood from the infusion arm was assayed for plasma propofol concentrations. In study 2, after left stellate block (12 ml 0.25% bupivacaine + 1% lidocaine), six participants were anesthetized and maintained with propofol infusions of 125 and 200 micrograms.kg-1.min-1. Simultaneous right forearm (unblocked) blood flow dynamics served as the time control. In three additional conscious participants, intrabrachial artery infusions of SNP and nitroglycerin, both at 10 micrograms/min, were performed before and after stellate blockade of the left forearm to determine whether the sympathetically denervated forearm vessels could dilate beyond the level produced by denervation alone. Results In study 1, infusion of intralipid or propofol into the brachial artery did not change FVR or FVC. Sodium nitroprusside significantly decreased FVR in a dose-dependent manner by 22 +/- 5%, 65 +/- 3%, and 78 +/- 2% (mean +/- SEM) but did not change FVC. During the incremental propofol infusions, plasma propofol concentrations increased from 0.2 to 10.1 micrograms/ml and averaged 7.4 +/- 1.1 micrograms/ml during the highest infusion rate. In study 2, stellate ganglion blockade decreased FVR by 50 +/- 6% and increased FVC by 58 +/- 10%. Propofol anesthesia at 125 and 200 micrograms.kg-1.min-1 progressively reduced mean arterial pressure. In the arm with sympathetic denervation, FVR and FVC showed no further changes during propofol anesthesia, whereas in the control arm FVR significantly decreased by 41 +/- 9% and 42 +/- 7%, and FVC increased significantly by 89 +/- 27% and 85 +/- 32% during 125 and 200 micrograms.kg-1.min-1 infusions of propofol, respectively. In the three additional conscious participants, intraarterial infusion of SNP and nitroglycerin (TNG) after the stellate blockade resulted in a further decrease of FVR and a further increase of FVC. Conclusions In contrast to SNP infusions, propofol infusions into the brachial artery of conscious persons caused no significant vascular responses, despite the presence of therapeutic plasma concentrations of propofol within the forearm. The effects of propofol anesthesia on FVR and FVC are similar to the effects of sympathetic denervation by stellate ganglion blockade. Thus the peripheral vascular actions of propofol appear to be due primarily to an inhibition of sympathetic vasoconstrictor nerve activity.

A deep, predominantly Ha, imaging survey of 37 classical nova remnants has just been completed using the William Herschel and Anglo-Australian Telescopes. This has resulted in the detection of new nebular remnants and the resolution of detailed structure in previously known remnants. These data indicate a correlation between nova speed class and the ellipticity of the resulting remnants – those of faster novae tend to comprise randomly distributed clumps of ejecta superposed on spherically symmetric diffuse material, whilst slower novae produce more structured ellipsoidal remnants with at least one, and sometimes several, rings of enhanced emission.

This study aimed to evaluate and validate chemical shift imaging (CSI) for in vivo glutamate (Glu) quantification in patients with supratentorial gliomas. If validated, CSI could become an extremely useful tool to investigate metabolic dysfunction of Glu in excitotoxic neuropathologies. Quantitative CSI estimates of Glu concentrations were compared with known concentrations of Glu in aqueous phantom solutions. Forty-one patients with known or likely supratentorial gliomas underwent preoperative CSI. The spectra obtained were analyzed for Glu concentrations and Glu to creatine (Cr) ratios. These in vivo measurements were correlated against ex vivo Glu content quantified by high performance liquid chromatography (HPLC) measured in 65 resected brain tumor and peritumoral brain specimens. For the phantom solutions the CSI estimates of Glu concentration and the Glu/Cr ratios were highly correlated with known Glu concentration (r² = 0.95, p = 0.002, and r² = 0.97, p 0.0001, respectively). There was a modest, but statistically significant, correlation between the ex vivo measured Glu and in vivo spectroscopic Glu concentration (r² = 0.22, p = 0.04) and ratios of Glu to Cr (r² = 0.30, p = 0.002). Quantitative measurement of Glu content is feasible in patients with supratentorial gliomas using CSI. The in vitro and in vivo results suggest that this has the potential to be a reliable quantitative imaging assay for brain tumor patients. This may have wide clinical research applications in a number of neurological disorders where Glu excitotoxicity and metabolic dysfunction are known to play a role in pathogenesis, including tumor associated epilepsy, epilepsy, stroke and neurotrauma.

To estimate the prevalence and demographic distribution of treated epilepsy in a community-based population.We surveyed all residents in Tasmania, Australia, who were supplied at least one antiepileptic drug prescription between July 1, 2001 and June 30, 2002, recorded on the national prescription database. We adjusted for the effect of disease-related non-response bias by imputation methods.After three mail contacts, 54.0% (4072/7541) responded, with 1774 (43.6%) indicating treatment for epilepsy, representing 86.0% of the estimated total possible cases in Tasmania. The adjusted treated epilepsy prevalence was 4.36 per 1000 (95% CI 4.34, 4.39); lower in women (prevalence ratio 0.92 (95% CI 0.84, 1.00)); greater with increasing age (P0.001); similar in the three main geographic regions; and similar with socioeconomic status of postcode of residence.Although our estimates are likely to be affected by access to health services, overall treated epilepsy prevalence of 4.4 per 1000 is similar to previous studies. Our finding of high elderly prevalence has been reported in a few recent studies in developed countries and has important clinical and public health implications in populations with similar aging demographics.

Longitudinal epiphyseal bracket (LEB) is a rare ossification anomaly in which an epiphysis brackets the diaphysis of a phalanx, metacarpal, or metatarsal. This abnormal epiphysis tethers longitudinal growth, resulting in a shortened and oval-shaped bone. Four patients with five LEBs were treated by central physiolysis and followed for a mean of 6 years. The patients had significant hallux varus deformity. Three patients had duplicated great toes, and two had tibia hemimelia significant enough to require epiphysiodesis as they neared adolescence. Resection of the LEB allowed the proximal and distal epiphysis to resume untethered growth. Silastic or methyl methacrylate was placed over the resected physis to prevent bony rebridging. The associated hallux varus deformity was corrected by capsulorrhaphy and K-wire fixation. In all patients, the metatarsal resumed longitudinal growth and correction of the hallux varus was maintained.

In studies investigating foetal malformations associated with antiepileptic drug exposure during pregnancy, the common practice has been to assess the incidence and nature of the malformations at, or soon after, birth. The adequacy of this approach to determine the true incidence of the malformations has received little attention.To compare the incidence and natures of the foetal malformations recognized by, or soon after, birth with similar data for malformations recognized in the first post-natal year.Analysis of data from the Australian Register of Antiepileptic Drugs in Pregnancy.Up to 25% of the malformations recognized by the end of the first post-natal year had not been detected by, or soon after, birth. There was a tendency for the late-recognized malformations to differ from the early-recognized ones in relation to the body parts involved.Early assessment and delayed assessment of infants for the presence of foetal malformations are complementary, with the latter resulting in finding a higher incidence of malformations. However, omission of an early post-natal assessment may result in biases because of loss of subjects to follow-up.

CA 125 is an antigenic determinant located on the surface of ovarian carcinoma cells and elevated in the serum of greater than 90% of patients with carcinoma. The antigen, derived from the ovarian epithelium, has been described as a mucinlike glycoprotein greater than 200 kd. To date little is known of the metabolic regulation or expression of this antigen in either normal or neoplastic tissues. New monoclonal antibodies that we describe here recognize both unique and similar epitopes to OC 125. These reagents may allow for a more complete definition of the structure and expression of the CA 125 complex. These antibodies recognize high-molecular weight (greater than 200 kd) subspecies and a lower-molecular-weight (68 kd) subspecies of the antigen and identify it in the cytoplasm and the extracellular matrix of CA 125-producing cells.

Two hundred eighty-one patients underwent magnetic resonance (MR) imaging of the shoulder over a 2-year period. Eighty-eight patients underwent arthroscopic surgery, and their surgical results were correlated with the findings at MR imaging. MR imaging enabled accurate prediction of anterior labral tears, with a sensitivity of 95%, a specificity of 86%, and an accuracy of 92%. MR imaging was less effective in the prediction of tears of the superior labrum, with a sensitivity of 75%, a specificity of 99%, and an accuracy of 95%. These two categories accounted for the majority of the surgically correctable disease. MR imaging was found to be unreliable in the prediction of posterior (sensitivity, 7.7%) or inferior (sensitivity, 40%) labral tears, isolated cases of which occurred in only two (2%) of those undergoing surgery. MR imaging proved to be a highly accurate, noninvasive technique for the clinical evaluation of shoulder instability.

Vulvovaginitis in the prepubertal child may present with itch, irritation, pain, dysuria or discharge as a result of poor hygiene, contact irritants, sexual abuse or skin disease involving the genital area. Common infectious causes include threadworms, group A beta-haemolytic streptococci and Haemophilus influenzae. A full history and examination are essential. Investigations may include swabs, midstream urine, biopsy, ultrasound and examination under anaesthesia.

The cellular responses to carcinogen exposure influence cellular fate, which in turn modulates the neoplastic response. Certain hexavalent chromium [Cr(VI)] compounds are implicated as occupational respiratory carcinogens at doses that are both genotoxic and cytotoxic. We examined the mechanism of Cr(VI)-induced apoptosis in normal human fibroblasts (BJ) immortalized by human telomerase gene transfection (BJ-hTERT), and we assessed the spectrum of cumulative cellular fates [(a) regaining of replicative potential; (b) terminal growth arrest; or (c) apoptosis] for a narrow range of increasingly genotoxic doses of Cr(VI). Exposure of BJ-hTERT cells to Cr(VI) resulted in a dose-dependent increase in apoptosis that involved mitochondrial disruption as evidenced by mitochondrial membrane depolarization and cytochrome c release. The initial response to Cr(VI) exposure was inhibition of cell cycle progression. At the lowest dose tested (1 microM; 32% clonogenic survival), the cell cycle inhibition led to terminal growth arrest but no apoptosis. The fraction of terminally growth arrested cells increased as the dose was increased to 3 microM but then decreased at 4, 5, and 6 microM as apoptosis became the predominant cell fate. Our results suggest that cell populations exposed to Cr(VI) have a different spectrum of responses, depending on the extent of DNA damage, and that the regaining of replicative potential after relatively higher genotoxic exposures may be attributable to either escape from, or resistance to, terminal growth arrest or apoptosis.

We investigated the relationship between cyclin E mRNA overexpression and p53 protein accumulation in epithelial ovarian cancers.mRNA was isolated and cDNA was prepared from 36 epithelial ovarian tumors (three adenomas, three low malignant potential tumors, and 30 carcinomas), and six normal ovaries. The cyclin E mRNA expression levels relative to an internal control, beta-tubulin, were determined by semiquantitative polymerase chain reaction (PCR). Cyclin E and p53 protein expression in ovarian cancer tissues were examined by immunohistochemistry using the same series of samples. Fisher exact test of significance and an unpaired t test were used for statistical analysis.Considerable levels of cyclin E mRNA were detected in all normal ovaries and ovarian tumor samples examined by semiquantitative PCR amplification. mRNA levels of cyclin E were significantly higher in nine of 30 (30%) ovarian cancers compared with those in normal ovaries. The immunohistochemical expression of cyclin E protein was confirmed in the nuclei of tumor cells in 13 of 30 (43%) ovarian cancers. p53 protein accumulation was detected in 12 of 30 (40%) ovarian cancers examined. There was a significant inverse correlation between cyclin E mRNA overexpression and p53 protein accumulation (P.01, Fisher exact test).Cyclin E mRNA overexpression frequently occurs in ovarian cancers without p53 protein accumulation. Cyclin E might have an important effect on the development of a limited number of ovarian cancers.

In a continued effort to identify and characterize secreted proteases that are overexpressed in ovarian carcinomas, we discovered the testisin protease as such a candidate. When this discovery was originally made, no data existed in the literature or in the GenBank database that identified such a gene. Our main objective was to determine whether this gene was overexpressed exclusively in ovarian tumor tissues compared with normal ovary and whether it was expressed in any other normal tissues.mRNA was isolated and cDNA was prepared from 34 ovarian tumors (four adenomas, three low malignant potential tumors, and 27 carcinomas) and seven normal ovaries. The testisin mRNA expression level relative to internal control, beta-tubulin, was determined by Northern blot analysis and semiquantitative polymerase chain reaction (PCR).Northern blot hybridization showed that the testisin transcript was abundant in ovarian carcinoma but was not detected in normal ovary. On examination of Northern blots from normal fetal and adult tissues, only adult testis showed abundant transcripts of testisin. Semiquantitative PCR examination showed that the testisin mRNA levels in ovarian tumors of low malignant potential and in ovarian carcinomas were significantly higher than in normal ovaries (P.01). Testisin mRNA level in ovarian carcinomas was also significantly higher than in ovarian adenomas (P.05). Testisin overexpression rates in advanced stage (stage 2 or 3) diseases were significantly higher than that in early stage diseases (stage 1) in ovarian carcinoma samples (P.05).The induction of the testisin transcript might contribute to the development, progression, and invasive or metastatic capacity of ovarian carcinomas.

Patients with medically intractable partial epilepsy and well-defined symptomatic MRI lesions were studied using phase-encoded frequency spectral analysis (PEFSA) combined with low-resolution electromagnetic tomography (LORETA). Ten patients admitted to the epilepsy monitoring unit with MRI-identified lesions and intractable partial epilepsy were studied using 31-electrode scalp EEG. The scalp electrodes were located in three-dimensional space using a magnetic digitizer and coregistered with the patient's MRI. PEFSA was used to obtain a phase-encoded scalp map for the ictal frequencies. The ictal generators were obtained from the scalp map using LORETA. In addition, the generators of interictal epileptogenic spikes were identified using time-domain LORETA. The LORETA generators were rostral to the MRI lesion in 87% (7/8) of patients with temporal lobe lesions, but all were located in the mesial temporal lobe in concordance with the patients' MRI lesions. In patients with frontal lobe epilepsy, the ictal generators at the time that the spectral power was maximal localized to the MRI lesions. Eight of 10 patients had interictal spikes, of which 4 were bilateral independent temporal lobe spikes. Only generators of the interictal spikes that were ipsilateral to seizure onset correlated with the ictal generators. LORETA combined with PEFSA of the ictal discharge can localize ictal EEG discharges accurately and improve correlation with brain anatomy by allowing coregistration of the ictal generator with the MRI. Analysis of interictal spikes was less useful than analysis of the ictal discharge.

Proteases play essential roles in the process of tumor invasion and metastasis. The serine protease stratum corneum chymotryptic enzyme (SCCE) has been purified from human stratum corneum and is known to contribute to the cell shedding process by catalyzing the degradation of intercellular cohesive structures at the skin surface. The presence of SCCE on the surface of tumor cells suggests it also may contribute to the process of tumor cell shedding, resulting in early metastasis of carcinoma.Gene expression of SCCE was investigated in 44 ovarian tumors (12 low malignant potential tumors and 32 carcinomas) and 10 normal ovaries by quantitative polymerase chain reaction (PCR). The PCR product was labeled with (32)P and a phosphoimager was used to determine the relative expression of SCCE compared with an internal control Beta-tubulin. mRNA transcripts were studied by Northern blot hybridization and protein expression and localization was examined by Western blot analysis and immunohistochemistry.mRNA expression levels of SCCE were elevated significantly in 66.7% of 12 low malignant potential tumors and 78.1% of 32 carcinomas. Furthermore, SCCE protein was abundant in tumor cells and tumor cell lines that overexpressed the mRNA transcript.The results of the current study suggest that SCCE frequently is overexpressed in ovarian tumors and therefore may contribute to tumor cell growth, tumor spread, and the metastatic potential of ovarian tumor cells.

Thoracic spine stabilization after trauma or in tumor reconstruction cases frequently is performed with hook and rod internal fixation systems, the use of which is not always possible. Pelvic reconstruction plates with pedicle screw fixation offer an alternative to hooks and rods. In this study, we biomechanically compared a plate construct with a hook and rod system in an acute postoperative, unstable thoracic spine model. We found that the hook and rod system offered more resistance to flexion and extension bending than the plate construct; the opposite was true for lateral bending and axial torsion. We further determined that the addition of pars interarticularis screws to the plate construct provided increased resistance to all loading modes. Our study indicates that plate constructs can effectively stabilize the thoracic spine.

In 1997 CA 125 celebrated its 15th anniversary. Since the discovery of OC 125, an antibody that recognizes CA 125, by Bob Bast and his colleagues, considerable progress has been made toward the development of more sensitive and more precise assay systems. However, a great deal of mystery still remains about the CA 125 molecule and further enlightenment will probably not come until the gene for CA 125 is cloned and the complete open reading frame for the peptide core identified. In the meantime, we have learned some structural features of the CA 125 molecule as well as a little about its regulation and the requirements for its secretion or release from epithelial derived cells in cultures. The CA 125 molecule is almost certainly a glycoprotein with a predominance of O-linkages. It is heterogeneous with regard to both size and charge, most likely due to continuous deglycosylation of side chains during its life-span in bodily fluids. It exists as a very large complex (perhaps as much as 4 million daltons) under natural conditions. The core CA 125 subunit is in excess of 200,000 daltons and it retains the capacity to bind both OC 125 class antibodies and M 11 class antibodies. As a denatured purified subspecies the CA 125 molecule appears to autoproteolyse presumably due to an endogenous protease activity inherent to the molecule. Release or secretion of CA 125 appears directly linked to the epithelial growth factor receptor signal transduction pathway. Prior to its release from cultured cells, CA 125 is phosphorylated (at either/both serine and threonine) and dephosphorylated when released. To stimulate discussion on the regulation of CA 125 synthesis, its secretion and its structural configuration, we have presented a model of a theoretical CA 125 molecule. Perhaps it will provide a focus of attention until the CA 125 gene is cloned and the real molecule is described.

We report on a 28-year-old man with long-standing intractable complex partial and secondary generalized seizures, whose magnetic resonance imaging scans 4 years apart documented progressive decrease in the left hippocampal volume. Left anterior temporal lobectomy with amygdalohippocampectomy rendered the patient seizure free at 12 months' follow-up. The findings demonstrate that patients with uncontrolled temporal lobe seizures may develop progressive atrophy of the hippocampus, in the absence of status epilepticus.

Scalp-recorded EEG is a noninvasive and widely available tool for studying normal and dysfunctional human neurophysiology with unsurpassed temporal resolution. However, scalp-recorded EEG data is difficult to correlate with anatomy, and most current display and neural source estimation algorithms are based on unrealistic spherical or elliptical models of the head. It is possible to measure the positions of electrodes on the patient's scalp, and to register those electrode positions into the space of a high-resolution MRI volume, and to then use the patient-specific anatomy as the basis for display and estimation of neural sources. We use a surface matching algorithm to register digitized electrode and scalp surface coordinates to a three-dimensional MRI volume. This study uses fiducial markers in phantom and volunteer studies to quantitatively estimate the accuracy of the electrode registration method. Our electrode registration procedure is accurate to 2.21 mm for a realistic head phantom and accurate to 4.16 mm on average for five volunteers. This level of accuracy is considered within acceptable limits for clinical applications.

This study prospectively evaluates the likelihood of a return of military personnel to full duty after anterior cruciate ligament reconstruction. We report the results of 120 active duty military patients who underwent anterior cruciate ligament reconstruction with autogenous patella tendon. Mean follow-up was 29 months (range, 24-65 months). Time from injury to reconstruction was6 months in 90% of patients. Final Lysholm scores averaged 89 (range, 29-100). We found that 77% of patients returned to full duty, whereas 23% of patients were medically discharged from military service. The patient age, military rank, time from injury to surgery, and KT-1000 measurements did not correlate with either the Lysholm score or return to duty (p = 0.05). Severe chondromalacia (Outerbridge III or IV) did correlate with poor result (p = 0.043), and Lysholm score did correlate with return to duty (p = 0.003). Anterior cruciate ligament reconstruction offers a higher likelihood of return to full military duty than nonoperative treatment in a similar study.

Anesthetic induction and maintenance with propofol are associated with decreased blood pressure that is, in part, due to decreased peripheral resistance. Several possible mechanisms whereby propofol could reduce peripheral resistance include a direct action of propofol on vascular smooth muscle, an inhibition of sympathetic activity to the vasculature, or both. This study examined these two possibilities in humans by measuring the forearm vascular responses to infusions of propofol into the brachial artery (study 1) and by determining the forearm arterial and venous responses to systemic (intravenous) infusions of propofol after sympathetic denervation of the forearm by stellate blockade (study 2).Bilateral forearm venous occlusion plethysmography was used to examine forearm vascular resistance (FVR) and forearm vein compliance (FVC). Study 1 used infusion of intralipid (time control) and propofol at rates between 83 and 664 micrograms/min into the brachial artery of 11 conscious persons and compared responses to arterial infusions of sodium nitroprusside (SNP) at 0.3, 3.0, and 10 micrograms/min. Venous blood from the infusion arm was assayed for plasma propofol concentrations. In study 2, after left stellate block (12 ml 0.25% bupivacaine + 1% lidocaine), six participants were anesthetized and maintained with propofol infusions of 125 and 200 micrograms.kg-1.min-1. Simultaneous right forearm (unblocked) blood flow dynamics served as the time control. In three additional conscious participants, intrabrachial artery infusions of SNP and nitroglycerin, both at 10 micrograms/min, were performed before and after stellate blockade of the left forearm to determine whether the sympathetically denervated forearm vessels could dilate beyond the level produced by denervation alone.In study 1, infusion of intralipid or propofol into the brachial artery did not change FVR or FVC. Sodium nitroprusside significantly decreased FVR in a dose-dependent manner by 22 +/- 5%, 65 +/- 3%, and 78 +/- 2% (mean +/- SEM) but did not change FVC. During the incremental propofol infusions, plasma propofol concentrations increased from 0.2 to 10.1 micrograms/ml and averaged 7.4 +/- 1.1 micrograms/ml during the highest infusion rate. In study 2, stellate ganglion blockade decreased FVR by 50 +/- 6% and increased FVC by 58 +/- 10%. Propofol anesthesia at 125 and 200 micrograms.kg-1.min-1 progressively reduced mean arterial pressure. In the arm with sympathetic denervation, FVR and FVC showed no further changes during propofol anesthesia, whereas in the control arm FVR significantly decreased by 41 +/- 9% and 42 +/- 7%, and FVC increased significantly by 89 +/- 27% and 85 +/- 32% during 125 and 200 micrograms.kg-1.min-1 infusions of propofol, respectively. In the three additional conscious participants, intraarterial infusion of SNP and nitroglycerin (TNG) after the stellate blockade resulted in a further decrease of FVR and a further increase of FVC.In contrast to SNP infusions, propofol infusions into the brachial artery of conscious persons caused no significant vascular responses, despite the presence of therapeutic plasma concentrations of propofol within the forearm. The effects of propofol anesthesia on FVR and FVC are similar to the effects of sympathetic denervation by stellate ganglion blockade. Thus the peripheral vascular actions of propofol appear to be due primarily to an inhibition of sympathetic vasoconstrictor nerve activity.

We wished to ascertain whether the measurement of maternal serum human chorionic gonadotropin (MShCG) in the serum of pregnant women with unexplained elevations of maternal serum alpha-fetoprotein (MSAFP) would more precisely define those women at risk of adverse pregnancy outcomes. MShCG was measured in samples of serum obtained from women in the second trimester of pregnancy who had elevated MSAFP, normal Level II ultrasounds, and normal fetal karyotypes. Based on the characteristics of a receiver-operator curve for MShCG and birth weight, patients were divided into two groups and pregnancy outcomes were compared. Pregnant women with an unexplained elevation in MSAFP, who also had an abnormal MShCG (or = 0.5 MoMor = 2.5) were at significantly greater risk of delivering a low-birth-weight infant compared to women with a normal MShCG (43% and 15%, respectively; P = 0.013). They were also more likely to deliver a preterm infant (48% and 11.9%), respectively; P = 0.001). In the prediction of low birth weight, an abnormal MShCG had a sensitivity of 50%, a specificity of 81%, and a positive predictive value of 43%; in the detection of preterm delivery the values were 59%, 88%, and 48%, respectively. These findings suggest that in pregnant women with a second trimester unexplained elevation in MSAFP, abnormal MShCG levels may identify a group of women at high risk of preterm delivery or delivery of a low-birth-weight infant.

Background The speed, quality, and cost of mask induction of anesthesia and laryngeal mask airway insertion or tracheal intubation were studied in young non-premedicated volunteers given high inspired concentrations of sevoflurane (6 to 7%). Methods Twenty healthy persons who were 19 to 32 years old participated three times, received 6 l/min fresh gas flow, and were randomized to receive 6 to 7% sevoflurane in 66% nitrous oxide/28% oxygen by face mask until tracheal intubation (treatment 1) or until laryngeal mask airway insertion (treatment 3), or 6 to 7% sevoflurane without nitrous oxide to tracheal intubation (treatment 2). Participants exhaled to residual volume and took three vital capacity breaths of the gas mixture; thereafter ventilation was manually assisted. The time of exposure to the inhaled gas was varied for consecutive participants. It was either increased or decreased by 30-sec increments based on the failure or success of the preceding volunteer's response to laryngoscopy and intubation after a preselected exposure time. Failure was defined as poor jaw relaxation, coughing or bucking, or inadequate vocal cord relaxation. Results Loss of the lid-lash reflex in unpremedicated young volunteers was achieved in 1 min and did not differ among groups. Average time (and 95% confidence interval) for acceptable conditions for LMA insertion was achieved in 1.7 (0.7 to 2.7) min, and all participants had an immediate return of spontaneous ventilation. The time for acceptable tracheal intubating conditions after manual hyperventilation by mask was 4.7 (3.7 to 5.7) min and 6.4 (5.1 to 7.7) min in treatments 1 and 2, respectively. There were no cases of increased secretions or laryngospasm. The incidence of breath holding and expiratory stridor ("crowing") was 7.5% and 25%, respectively, during treatment 1 and 15% and 40%, respectively, during treatment 2. Conclusions The induction of anesthesia to loss of lid reflex in young non-premedicated adults approaches the speed of intravenous induction techniques. No untoward airway responses were noted during mask induction of anesthesia with a three-breath technique. In response to intubation, no adverse airway responses, including jaw tightness, laryngospasm, and excessive coughing or bucking, occurred in participants whose duration of mask administration of sevoflurane met the appropriate times (as determined in this study).

To understand better the natural history of fractures of the fifth metatarsal, a fracture registry was established consisting of patients who had acute fractures of the fifth metatarsal. The first 100 patients were studied to develop data on the natural history of injuries to this bone, and on the results of standard treatment for those injuries. In this study, 3 fracture subtypes were identified: avulsion, true Jones' fracture, and shaft/neck fracture. Avulsion fractures healed without immobilization, usually in 4 weeks. Shaft/neck fractures healed in plaster casts with weight bearing as tolerated in 4 to 6 weeks. True Jones' fractures required a prolonged time to heal when treated with 8 weeks of nonweight bearing and then weight bearing as tolerated in a cast. This method was, however, successful in 72% of patients (average time until union, 21.2 weeks). For the 7 patients in whom conservative treatment failed, surgical fixation at an average of 25 weeks after injury reliably achieved bony union in half the time required with cast treatment. This low-risk procedure met with higher patient satisfaction than prolonged casting.

The properties of emulsions formed when water contacts low sulfur diesel fuel supplemented with indigenous surfactants or chemical additives were studied. Small amounts of the additives were found to have dramatic effects on the stabilization or breaking of the emulsions formed during ASTM D-1094 testing. Dynamic interfacial tension measurements were also recorded to determine the influence of the surfactants on the interfacial film surrounding the water droplets in the emulsions. The results of both the ASTM test and the interfacial tension measurements were compared. 18 refs., 19 figs.

Two cases of rhinocerebral mucormycosis in elderly, non-ketotic diabetics who were initially diagnosed and treated for bacterial periorbital cellulitis are reported. Both presented with a short history of periorbital pain and swelling followed rapidly by complete ophthalmoplegia and blindness. By the time of correct diagnosis, both cases were advanced with lower cranial nerve involvement, CT evidence of ophthalmic artery and cavernous sinus thrombosis and, in one, internal carotid artery invasion (demonstrated on MR angiography) with resultant cerebral infarction. One patient was treated with intravenous amphotericin B but died within a few days. The second patient had aggressive surgical resection and survived with significant residual morbidity. These cases illustrate that mucormycosis should be excluded in any diabetic patient presenting with orbital cellulitis, especially when there is early visual loss. Early aggressive treatment with surgery and antifungal agents is often successful whereas the outcome is almost universally fatal when the diagnosis is delayed.

We studied the relation between epidermal growth factor (EGF)/epidermal growth factor receptor (EGFR) and CA125 production in WISH cells.We investigated quantitatively and immunohistochemically EGF-stimulated CA125 release from WISH cells and the effect of EGF on CA125 phosphorylation.Immunohistochemical staining demonstrated that CA125 and EGFR expression on the plasma membrane of the WISH cells was closely correlated with cell density. The WISH cell monolayers (day 4) stained for CA125 in both the cytoplasm and plasma membrane. By day 8, cells began to form clumps in the surrounding monolayer that were positive for membrane-associated CA125 and EGFR, while the monolayer was almost negative for both molecules. Four-day and 8-day cells exposed to EGF demonstrated a loss of both CA125 and EGFR staining. Epidermal growth factor increased the secreted CA125 levels by 50% in day-4 cells but had no effect on day-8 cells. CA125 from WISH cells was phosphorylated, and EGF further enhanced this phosphorylation.

Isaac's syndrome is an uncommon, but distressing, condition of spontaneous abnormal muscle activity caused by neuronal hyperexcitability possibly due to damage to slow potassium channels. The underlying aetiology may be peripheral nerve damage from a wide variety of causes, including autoimmune disease. We report a case that failed to respond to carbamazepine or phenytoin but responded dramatically to valproic acid. Thus, valproic acid may be an effective treatment for Isaac's syndrome where these other drugs have failed.

To determine if serum beta-hCG levels are higher in multiple gestation than in singleton pregnancy at the time of intrauterine sac visualization and the first appearance of fetal heart activity as documented by serial transvaginal ultrasound (US).Prospective analysis of serial transvaginal US findings in 19 pregnancies correlated with serum hCG levels during early gestation.Reproductive endocrinology division of the University of Arkansas for Medical Sciences, Little Rock, Arkansas.Nineteen infertility patients were studied after conceiving. Thirteen underwent IVF or GIFT, 4 received hMG therapy, 1 was treated with clomiphene citrate, and 1 pregnancy followed spontaneous ovulation.Transvaginal US and hCG levels were obtained every Monday, Wednesday, and Friday from 20 to 22 days after ovulation until the appearance of fetal heart activity.Initial sac visualization occurred at lower serum hCG levels in singleton versus multiple pregnancies (2,180 +/- 1,170 versus 7,028 +/- 4,280 mIU/mL, mean +/- SD). Sacs were always seen when the serum hCG level (mIU/mL) wasor = 1,161 in singleton, 1,556 in twin, 3,372 in triplet, and 9,399 in quadruplet pregnancies.Failure to observe an intrauterine sac by transvaginal US in the presence of serum hCG levels in the 1,000 to 2,000 mIU/mL range is not pathognomonic for an ectopic gestation. Clinical symptomatology, risk of multiple pregnancies, and gestational age must also be considered.

Osteonecrosis is a common sequela of long-term steroid therapy. This paper presents the only case of multifocal osteonecrosis to occur after a short-term course of methylprednisolone for treatment of septic shock. Two years after receiving a two-week course of corticosteroid treatment, the patient developed pain in his right and left shoulders and left hip. Roentgenograms and magnetic resonance imaging revealed changes consistent with osteonecrosis of both humeral heads and the femoral head. The patient failed to respond to conservative treatment and eventually was treated with bipolar hip replacement.

Osteonecrosis is a common sequela of long-term steroid therapy. This paper presents the only case of multifocal osteonecrosis to occur after a short-term course of methylprednisolone for treatment of septic shock. Two years after receiving a two-week course of corticosteroid treatment, the patient developed pain in his right and left shoulders and left hip. Roentgenograms and magnetic resonance imaging revealed changes consistent with osteonecrosis of both humeral heads and the femoral head. The patient failed to respond to conservative treatment and eventually was treated with bipolar hip replacement.