Lower uterine segment scar assessment at 11-14 weeks' gestation to screen for placenta accreta spectrum in women with prior Cesarean delivery.

OBJECTIVES: To validate prospectively transvaginal ultrasound assessment of the lower uterine segment (LUS) scar at the time of first-trimester screening in women with previous Cesarean section (CS) and to determine its feasibility and accuracy in stratifying women according to the risk for placenta accreta spectrum (PAS) disorder. METHODS: Women with a history of CS were recruited between 11 + 0 and 13 + 6 weeks' gestation and underwent LUS scar assessment using transvaginal ultrasound. A standardized midsagittal plane, which included the cervicoisthmic canal (CIC), the uterine scar and the placental site, was obtained. The scar was described in terms of its size (narrow or dehiscent) and its location in relation to the CIC (within or above), with each LUS scar classified into one of four groups based on these features. Placental location was assessed and classified as high- or low-lying. Women were stratified according to the risk of PAS, based on the relationship between the scar location and placental site. Women were considered high risk when the scar was above the CIC and the placenta was low-lying (i.e. when the placenta was overlying an exposed scar) and low risk when the scar was within the CIC and/or the placenta was high. High-risk patients were followed up at 20 weeks and 28-30 weeks for the development of PAS. Maternal demographics, detailed obstetric history and obstetric outcome were collected. RESULTS: First-trimester transvaginal ultrasound was offered to 535 women with prior CS during the study period. A LUS scar was visualized in 79.9% (401/502) of those who agreed to undergo the examination. At this scan, the LUS scar was above the CIC in 9.0% (36/401) of women, but only 5.7% (23/401) additionally had a low-lying placenta overlying the scar. Of these 23 high-risk women, two were found to have PAS on the mid-trimester screening scan and one was noted to have placental adherence during evacuation following mid-trimester termination of pregnancy. On the first-trimester scan, 94.3% (378/401) of women were at low risk of PAS. This screening protocol yielded a positive likelihood ratio of 21.33 (95% CI, 13.02-34.96), sensitivity of 100% (95% CI, 29.24-100%), specificity of 95.31% (95% CI, 92.39-97.35%), positive predictive value of 16.7% (95% CI, 5.8-39.2%) and negative predictive value of 100% (95% CI, 98.4-100%). On multivariable regression analysis performed to identify confounding variables associated with a LUS scar above the CIC, only maternal body mass index ≥ 30 kg/m2 was significant (odds ratio (OR), 2.42 (95% CI, 1.04-5.39); P = 0.03). Although there was a trend towards an increased risk of a LUS scar above the CIC in women with prior elective prelabor CS (OR, 1.72 (95% CI, 0.80-3.68)), this association did not reach statistical significance. CONCLUSIONS: Routine transvaginal ultrasound assessment of the location of the LUS scar and placenta at the time of first-trimester screening between 11 + 0 and 13 + 6 weeks' gestation in women with prior CS is a feasible and effective tool to identify those at risk of subsequent development of PAS disorder. A finding of placental implantation over an exposed LUS scar seems to be cardinal in predicting the risk of PAS disorder in women with prior CS, with an excellent negative predictive value. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.

Uterine conservation in placenta accrete spectrum (PAS) disorders: A retrospective case series: Is expectant management beneficial in reducing maternal morbidity?

OBJECTIVE: To examine whether expectant management confers any benefit on operative morbidity for the management of placenta accrete spectrum (PAS) disorders. STUDY DESIGN: This was a single center retrospective cohort study at a tertiary referral center In Singapore. Women with PAS disorder between January 2006 and December 2017 were identified from the hospital register. Antenatal features, surgical factors and post-operative morbidity were compared between women having caesarean hysterectomy, those having caesarean section with placental removal and women having expectant management, defined as caesarean section with retention of placenta using the student's t and Chi square tests. The natural course, complications and preservation of fertility were examined for women having expectant management. RESULTS: Ninety women with PAS were included. The incidence of PAS was 0.064 %. Mean gestational age (GA) at diagnosis was 26.4 weeks. Elective and emergency deliveries were performed at 36.7 and 32.4 weeks respectively (p = <0.0001). Caesarean hysterectomy, Caesarean section with placenta removal and expectant management (EM) were performed in 51(56.7 %),16(17.8 %) and 23(25.6 %) women respectively. The mean blood loss (MBL) and surgical time for EM were significantly lower than those for caesarean hysterectomy 0.52 L vs 3.17 L (p < 0.0001) and 70.8 min vs 171.6 min (p < 0.0001). The advantage of lower blood loss with expectant management persisted even after blood loss at delayed hysterectomy was considered (1284.09 mL vs 3168.72 mL (p-value <0.0001)). Uterine preservation with EM was successful in 61 % (14/23) women. Although nine women (39 %) in this group needed hysterectomy most complications were minor and presented within three months. The mean follow up overall was 13 months. CONCLUSION: Traditionally caesarean hysterectomy has been the main surgical approach for PAS. Our study consolidates existing evidence for expectant management being an option for a select group of patients to avoid complications associated with hysterectomy and allow uterine preservation.

High temporal resolution gastric emptying breath tests in mice.

BACKGROUND: Gastric emptying is a complex physiological process regulating the division of a meal into smaller partitions for the small intestine. Disrupted gastric emptying contributes to digestive disease, yet current measures may not reflect different mechanisms by which the process can be altered. METHODS: We have developed high temporal resolution solid and liquid gastric emptying breath tests in mice using [13 C]-octanoic acid and off axis- integrated cavity output spectroscopy (OA-ICOS). Stretched gamma variate and 2-component stretched gamma variate models fit measured breath excretion data. KEY RESULTS: These assays detect acceleration and delay using pharmacological (7.5 mg/kg atropine) or physiological (nutrients, cold exposure stress, diabetes) manipulations and remain stable over time. High temporal resolution resolved complex excretion curves with 2 components, which was more prevalent in mice with delayed gastric emptying following streptozotocin-induced diabetes. There were differences in the gastric emptying of Balb/c vs C57Bl6 mice, with slower gastric emptying and a greater occurrence of two-phase gastric emptying curves in the latter strain. Gastric emptying of C57Bl6 could be accelerated by halving the meal size, but with no effect on the occurrence of two-phase gastric emptying curves. A greater proportion of two-phase gastric emptying was induced in Balb/c mice with the administration of PYY (8-80 nmol) 60 min following meal ingestion. CONCLUSIONS AND INFERENCES: Collectively, these results demonstrate the utility of high temporal resolution gastric emptying assays. Two-phase gastric emptying is more prevalent than previously reported, likely involves intestinal feedback, but contributes little to the overall rate of gastric emptying.

Topology, divergence dates, and macroevolutionary inferences vary between different tip-dating approaches applied to fossil theropods (Dinosauria).

Dated phylogenies of fossil taxa allow palaeobiologists to estimate the timing of major divergences and placement of extinct lineages, and to test macroevolutionary hypotheses. Recently developed Bayesian 'tip-dating' methods simultaneously infer and date the branching relationships among fossil taxa, and infer putative ancestral relationships. Using a previously published dataset for extinct theropod dinosaurs, we contrast the dated relationships inferred by several tip-dating approaches and evaluate potential downstream effects on phylogenetic comparative methods. We also compare tip-dating analyses to maximum-parsimony trees time-scaled via alternative a posteriori approaches including via the probabilistic cal3 method. Among tip-dating analyses, we find opposing but strongly supported relationships, despite similarity in inferred ancestors. Overall, tip-dating methods infer divergence dates often millions (or tens of millions) of years older than the earliest stratigraphic appearance of that clade. Model-comparison analyses of the pattern of body-size evolution found that the support for evolutionary mode can vary across and between tree samples from cal3 and tip-dating approaches. These differences suggest that model and software choice in dating analyses can have a substantial impact on the dated phylogenies obtained and broader evolutionary inferences.

Effect of forage type with or without corn supplementation on animal performance, beef fatty acid composition, and palatability.

Thirty-two steers were used to examine forage type (legumes [ and ] vs. grasses [ and ]) with or without individual corn grain supplementation (0 vs. 0.75% of live weight [LW]/d) on beef fatty acid composition and palatability. In each year, steers ( = 16/yr) were randomly assigned to forage type ( = 8/forage type per yr) and to supplementation treatments within forage type ( = 4/supplementation treatment/forage type per yr). Forage types (grasses vs. legumes) were replicated in 2 paddocks of perennial and annual forage type pastures. A mixed model was developed with forage type, corn grain supplementation, and the 2-way interaction as fixed effects and 2 different error terms, one for testing forage and another for testing grain supplement and grain supplement × forage interaction. Corn grain supplementation increased ( = 0.01) ADG by 0.29 kg/d and final LW by 13 kg. Hot carcass weight, dressing percentage (DP), and KPH were greater ( < 0.05) for steers supplemented with corn grain. Carcasses from steers grazing legumes had greater ( = 0.04) DP compared with carcasses from steers grazing grasses. Alpha-linolenic acid concentration was higher ( < 0.05) in LM of steers grazing legumes than in LM of steers grazing grasses, both without supplementation. Supplementation decreased ( < 0.05) linolenic acid levels for both forage types; however, the magnitude of this reduction was greater for legumes than for grasses. The ratio of -6 to -3 PUFA was greater ( = 0.03) in the LM of corn grain-supplemented steers than in the LM of nonsupplemented steers. Supplementation of corn grain decreased ( < 0.05) the percentage of odd-chain fatty acids and increased ( < 0.05) the percentage of MUFA in the LM. Warner-Bratzler shear force values were not altered ( > 0.05) by forage type, supplementation, or the 2-way interaction. Beef finished on legumes had greater concentrations of -3 PUFA, whereas beef supplemented with corn grain had a greater ratio of -6 to -3 fatty acids. On a gravimetric basis (mg/100 g LM), -3 PUFA and CLA contents were not altered with supplementation, indicating that corn grain can be supplemented at this level in a forage-finishing beef system without negative consequences on perceived beneficial fatty acids.

Sendai virus-mediated CFTR gene transfer to the airway epithelium.

The potential for gene therapy to be an effective treatment for cystic fibrosis has been hampered by the limited gene transfer efficiency of current vectors. We have shown that recombinant Sendai virus (SeV) is highly efficient in mediating gene transfer to differentiated airway epithelial cells, because of its capacity to overcome the intra- and extracellular barriers known to limit gene delivery. Here, we have identified a novel method to allow the cystic fibrosis transmembrane conductance regulator (CFTR) cDNA sequence to be inserted within SeV (SeV-CFTR). Following in vitro transduction with SeV-CFTR, a chloride-selective current was observed using whole-cell and single-channel patch-clamp techniques. SeV-CFTR administration to the nasal epithelium of cystic fibrosis (CF) mice (Cftr(G551D) and Cftr(tm1Unc)TgN(FABPCFTR)#Jaw mice) led to partial correction of the CF chloride transport defect. In addition, when compared to a SeV control vector, a higher degree of inflammation and epithelial damage was found in the nasal epithelium of mice treated with SeV-CFTR. Second-generation transmission-incompetent F-deleted SeV-CFTR led to similar correction of the CF chloride transport defect in vivo as first-generation transmission-competent vectors. Further modifications to the vector or the host may make it easier to translate these studies into clinical trials of cystic fibrosis.

Duration of effect of single-dose inhaled fluticasone propionate on AMP-induced bronchoconstriction.

Airway hyperresponsiveness induced by adenosine-5'-monophosphate (AMP) is regarded as a reliable model for allergic asthma and for the evaluation of anti-asthmatic drugs. Single-dose inhaled corticosteroids (ICS) are known to be protective in this model, but the duration of action of these drugs in this model has never been studied. The duration of ICS protection was determined by administration of single-dose fluticasone propionate (FP; 1,000 micrograms) up to 26 h before AMP challenge. A randomised, double-blind, placebo-controlled, four-way crossover study was performed in 13 mild asthmatics (mean +/- SD predicted forced expiratory volume in one second (FEV1) 98 +/- 7%). Each subject received placebo and FP (at 26, 14 or 2 h prior to the AMP challenge). Furthermore, the marker exhaled nitric oxide (eNO) was studied after administration at these time points to investigate whether eNO also demonstrates the duration of action of ICS. The doubling concentrations difference (DCD) of AMP causing a 20% fall in FEV1, when FP was administered 26, 14 or 2 h prior to challenge, was significantly increased as compared with placebo: DCD (95% confidence interval) at 26 h, 0.73 (0.20-1.26), p = 0.008; 14 h, 1.50 (0.99-2.01), p < 0.001; and 2 h, 2.89 (2.37-3.40), p < 0.001. However, eNO was not significantly affected at these time points. In conclusion, a single dose of 1,000 micrograms inhaled fluticasone propionate protects against adenosine-5'-monophosphate airway hyperresponsiveness up to 26 h after dosing. This study suggests that adenosine-5'-monophosphate challenge can be used as a sensitive marker to study the duration of action of inhaled corticosteroids.

Study of five cell salvage machines in coronary artery surgery.

We evaluated the effectiveness, ease of use and safety of five machines for blood salvage during coronary artery surgery. All were equally effective in concentrating red cells. We measured haemoglobin, packed cell volume, free haemoglobin, white cells, neutrophil elastase, platelets, thrombin-antithrombin complex (TAT), prothrombin activation peptide F1.2, fibrin degradation product (d-dimers), tissue plasminogen activator (tPA) and heparin in wound blood, in washed cell suspensions and in a unit of bank blood prepared for each patient. All machines were equally safe and easy to use and were equally effective in removing heparin and the physiological components measured. There were no adverse effects on patients. Clotting factors are severely depleted both in salvaged blood, even before washing, and in bank blood. Cell savers are a valuable adjunct to coronary artery surgery, but careful monitoring of coagulation is required when the volumes of either bank blood or salvaged blood are large.

A case of fatal food-borne septicemia: can family physicians provide prevention?

BACKGROUND: Vibrio vulnificus, a common bacteria found in undercooked seafood and seawater, is the leading cause of food-borne death in Florida. Fatal cases of V vulnificus infection have also been reported in most states. METHODS: The literature was searched using the key words "Vibrio vulnificus," "septicemia," "wound infections," "seafood," "immunocompromise," and "patient education." A case of fatal V vulnificus septicemia is described. RESULTS AND CONCLUSIONS: V vulnificus, part of the natural flora of temperate coastal waters and one of the most abundant microorganisms found in seawater, has been isolated from waters off the Gulf, Pacific, and Atlantic coasts of the United States. Infections in noncoastal regions have been traced to consumption of seafood derived from Gulf Coast waters. Seawater exposure and consumption of inadequately cooked seafood are routes most commonly associated with V vulnificus infection. Exposure to V vulnificus is life-threatening for chronically ill or immunocompromised patients, who are most likely to develop fatal septicemia. Currently a combination of doxycycline and intravenous ceftazidime is recommended treatment. Mortality rates from V vulnificus continue to be high in immunocompromised patients. Family physicians can help prevent this outcome by counseling high-risk patients.

Enhancement of retention and cytotoxicity of 2-chlorodeoxyadenosine in cultured human leukemic lymphoblasts by nitrobenzylthioinosine, an inhibitor of equilibrative nucleoside transport.

In leukemic cells exposed to 2-chlorodeoxyadenosine (2-CdA), levels of the nucleoside drug and its phosphate metabolites decay with time in the absence of external 2-CdA; an intrinsic part of this process is the efflux of 2-CdA. The effects of nitrobenzylthioinosine (NBMPR) and of dipyridamole (DPM), both potent inhibitors of es (e, equilibrative; s, sensitive to NBMPR) nucleoside transport processes, were studied in four lines of cultured leukemic lymphoblasts. Suspensions of 2-CdA-loaded cells were diluted 10-fold with 2-CdA-free medium to initiate the cellular 2-CdA decay processes, which followed a biexponential time course. When diluting media contained NBMPR or DPM, intracellular levels of 2-CdA and its metabolites were substantially increased (P < 0.001) compared with cells in media lacking the transport inhibitors, and 2-CdA loss followed a monoexponential time course. As a consequence, the AUCs (area under time-course plots of intracellular 2-CdA and its metabolites) were significantly (P < 0.001) lower in untreated control cells compared to inhibitor-treated cells. These results suggest that nucleoside transport processes contribute to the efflux of 2-CdA from the cultured lymphoblasts. The cytotoxicity of 1-h exposure to 2-CdA of Reh-A2 and CCRF-CEM cells was enhanced three-fold by subsequent exposure to 0.5 microM NBMPR relative to that of control cells subjected to the same manipulations without NBMPR exposure. However, before such a strategy may be considered to have a therapeutic application, careful examination of effects in normal lymphocytes and ex vivo leukemic lymphoblasts must first be undertaken. Leukemia (2000) 14, 52-60.

Degenerative displacement of lumbar vertebrae. A 25-year follow-up study in Framingham.

STUDY DESIGN: The authors assessed degenerative lumbar displacement in a population-based cohort of 217 men and 400 women who had lateral lumbar radiographs performed at the mean age of 54 years and again at 79 years, and who had completed interviews on back symptoms and functional performance in connection with the follow-up examination. OBJECTIVES: To assess the prevalence and incidence of degenerative slippage and its association with back pain and physical disability. SUMMARY OF BACKGROUND DATA: Degenerative displacement of lumbar vertebrae may cause instability, nerve root compression, and spinal stenosis. Its incidence in the older population and association with back pain and disability are unknown. METHODS: The authors assessed the prevalence and incidence of degenerative slippage from lateral lumbar radiographs performed 25 years apart and its association with back pain and physical disability from interviews performed in connection with the follow-up examination. RESULTS: At the follow-up examination, 23 (12%) men and 100 (25%) women had developed degenerative slippage exceeding 3 mm; two of them had this already at the baseline. A forward displacement was found in 8 men and 76 women (P < 0.0001 for difference between the genders) and a backward one in 16 men and 35 women. On average, forward slip was 18% +/- 5.5, and backward slip, 15% +/- 4.0 of the anteroposterior diameter of the vertebra below. At the time of the second lumbar radiograph, 39 (32%) of the subjects with slippage, compared with 90 (19%) of the controls, had pain, aching, or stiffness in their back on most days (P = 0.001). After adjustment for endplate sclerosis, which was also related to pain (P = 0.015), slippage still had association with daily back symptoms (P = 0.009). However, subjects with slippage had not experienced more back symptoms during the preceding year or in earlier ages of life, and they did not report more disability than the controls. CONCLUSIONS: Degenerative displacement of lumbar vertebrae is common in an older population and is associated with increased prevalence of daily back symptoms. However, two thirds of the subjects with degenerative displacement do not report ongoing back symptoms, and the disorder is also unrelated to long-term back pain and physical disability.

Effects of haloperidol metabolites on neurotransmitter uptake and release: possible role in neurotoxicity and tardive dyskinesia.

This research explored the effects of haloperidol (HP) metabolites on biogenic amine uptake and release, and compared them to those of MPTP and its toxic metabolite, MPP+. In synaptosome preparations from mouse striatum and cortex, the HP metabolites haloperidol pyridinium (HPP+), reduced haloperidol pyridinium (RHPP+), and haloperidol tetrahydropyridine (HPTP) inhibited the presynaptic uptake of dopamine and serotonin, with greater affinity for the serotonin transporter. HPP+ was the most potent inhibitor of dopamine uptake, and HPTP of serotonin uptake, both with IC50 values in the low micromolar range. RHPP+ was less active than the other metabolites, but was more active than the parent compound, HP. Inhibition of uptake was reversed when free drug was removed by centrifugation and then resuspension of the synaptosomes in fresh buffer, suggesting that inhibition of uptake was due to interaction with the transporters and was not due to irreversible cytotoxicity. HPP+ showed noncompetitive inhibition of both serotonin and dopamine uptake, suggesting that it has a relatively slow dissociation rate for its interaction with the transporter proteins. In experiments on amine release, HPP+ and HPTP were four-fold less potent than MPP+ for releasing preloaded dopamine from striatal synaptosomes, and only MPP+-dependent release was antagonized by the uptake blocker, mazindol. In contrast, RHPP+ displayed little ability to release either amine neurotransmitter. HPTP was about two-fold more potent than MPP+ for releasing serotonin from cortical synaptosomes, whereas HPP+ was less active than MPP+. The specific serotonin transport blocker fluoxetine was only able to antagonize release induced by MPP+. These results suggest that HP metabolites bind to the transporters for dopamine and serotonin, but are not transporter substrates. In contrast to their potent effects on amine release, HPP+ and HPTP were unable to release preloaded GABA from cortical synaptosomes. The implications of these results concerning a possible role of HP metabolites in the development of tardive dyskinesia are discussed.

Caloric restriction and spatial learning in old mice.

Spatial learning in old mice (19 or 24 months old), some of which had been calorically restricted beginning at 14 weeks of age, was compared to that of young mice, in two separate experiments using a Morris water maze. In the first experiment, only old mice reaching criterion performance on a cued learning task were tested in a subsequent spatial task. Thus, all old mice tested for spatial learning had achieved escape latencies equivalent to those of young controls. Despite equivalent swimming speeds, only about half the old mice in each diet group achieved criterion performance in the spatial task. In the second experiment, old and young mice all received the same number of training trials in a cued task and then in a spatial task. Immediately following spatial training, they were given a 60-s probe trial, with no platform in the pool. Both groups of old mice spent significantly less time in the quadrant where the platform had been and made significantly fewer direct crosses over the previous platform location than did the young control group. As in Experiment 1, calorie restriction failed to provide protection against aging-related deficits. However, in both experiments, some individual old mice evidenced performance in spatial learning indistinguishable from that of young controls. Separate comparisons of "age-impaired" and "age-unimpaired" old mice with young controls may facilitate the identification of neurobiological mechanisms underlying age-related cognitive decline.

Biological indicators for low temperature steam and formaldehyde sterilization: investigation of the effect of change in temperature and formaldehyde concentration on spores of Bacillus stearothermophilus NCIMB 8224.

Five strains of Bacillus stearothermophilus have been studied to identify a spore strain to be used as a biological indicator organism for low temperature steam and formaldehyde sterilization. Three strains gave poor reproducibility of batch size and growth index and were discarded. The other two strains gave good reproducibility with a high growth index and gave rise to linear survivor curves when exposed to 5% aqueous formaldehyde. However, only NCIMB 8224 sporulates on a simpler medium and as it was the most resistant to formaldehyde, it was further studied. Tests were carried out in a modified miniclave and factors studied included temperature of the steam and formaldehyde concentration. All studies confirmed the suitability of this strain as a biological indicator organism.

Biological indicators for low temperature steam and formaldehyde sterilization: the effect of defined media on sporulation, growth index and formaldehyde resistance of spores of Bacillus stearothermophilus strains.

Preliminary screening was carried out on spores of 29 strains of Bacillus stearothermophilus to determine their potential as biological indicator organisms for low temperature steam and formaldehyde sterilization. Each strain was sporulated on four chemically defined media. Fourteen strains produced satisfactory sporulation on one or more of the media but there was considerable variation in the extent of sporulation. The growth index of the spores, which was dependent on both the strain of organism and the sporulation medium, ranged from 1% to 90%. The spores were appraised on the basis of their resistance to inactivation by 0.5% w/v formaldehyde in aqueous solution at 70 degrees C. The survivor curves obtained could be characterized into five types on the basis of the shape of the curve. Only five strains of Bacillus stearothermophilus produced spores with the characteristics of high resistance, linear semi-logarithmic survivor curve and high growth index that would be required of a potential biological indicator organism.

Immunolabeling of retrogradely transported Fluoro-Gold: sensitivity and application to ultrastructural analysis of transmitter-specific mesolimbic circuitry.

Fluorescence microscopy shows extensive filling of perikarya and distal dendrites following injections of Fluoro-Gold (FG) into their terminal fields. However, elucidation of synaptic contacts onto identified projection neurons has been limited by the lack of compatibility between electron-dense markers required for ultrastructural analysis and morphology preservation. The recent advent of antisera to FG has revealed numerous potential applications for analyzing chemically defined synaptic circuitry. To take advantage of the high sensitivity of this retrograde tracer in ultrastructural studies, we extended and detailed the original description of single immunocytochemical labeling of FG by comparing the advantages of immunodetection of an antiserum against FG using 2 distinct electron-dense markers: (1) avidin-biotin peroxidase (ABC) reacted with 3,3'-diaminobenzidine and darkened with osmium tetroxide, or (2) silver-intensified 1 nm colloidal gold particles. We subsequently examined the utility of combining these markers in single sections for detection of transmitters (e.g., gamma-aminobutyric acid (GABA) and 5-hydroxytryptamine (5-HT)) in axon terminals presynaptic to retrogradely labeled neurons. Both analyses were carried out on the well-characterized mesolimbic pathway originating from perikarya in the ventral tegmental area (VTA) that project to the nucleus accumbens. Injections of FG were stereotaxically placed in the nucleus accumbens of anesthetized adult rats. From these animals, vibratome sections of aldehyde-fixed brains were examined for light-microscopic detection of FG using: (1) epi-fluorescence without immunocytochemistry, (2) immunoperoxidase, or (3) immunogold-silver. All 3 methods revealed circumscribed injections in the nucleus accumbens. Additionally, both immunocytochemical methods appeared to be as sensitive as epi-fluorescence in light-microscopic detection of retrogradely labeled perikarya and fine-caliber dendrites extending for 2-3 branch points beyond the soma. Electron microscopy showed that the FG was detectable not only in lysosomes but also throughout the cytoplasmic matrix of perikarya and dendrites using either immunoperoxidase or immunogold-silver labeling methods. In the second part of this analysis, single sections of tissue were processed for dual labeling using either immunoperoxidase or immunogold-silver for detection of FG in conjunction with the converse label for GABA or 5-HT, respectively. Regardless of the labeling combinations, the peroxidase and gold-silver reactions were readily distinguished within sections examined by light or electron microscopy. Synaptic junctions from unlabeled or from GABA or 5-HT labeled terminals were most readily identified when the targets were lightly immunoreactive for peroxidase or labeled using silver-intensified colloidal gold.(ABSTRACT TRUNCATED AT 400 WORDS)

Deep venous thrombosis following posterior lumbar spinal surgery.

Postoperative duplex scans were performed on 185 patients undergoing posterior lumbar spinal surgery in order to identify deep venous thrombosis (DVT). Elastic compression stockings were used for prophylaxis in 74 patients (Group E.S.); intermittent pneumatic compression was used in the remaining 111 patients (Group P.C.). High-risk patients were not eliminated from either group. Laminectomy was performed on 84 patients (40 from Group E.S. and 44 from Group P.C.), and spinal fusion, on 101 patients (34 from Group E.S. and 67 from Group P.C.). A total of four patients, all from Group E.S., developed acute postoperative DVT. Intermittent pneumatic compression significantly reduced the incidence of acute postoperative DVT (P < 0.05). No statistically significant differences were found in the incidence of DVT in relation to the type of spinal procedure, length of procedure, duration of bed rest, or age of the patient. In conclusion, considering the low rate of DVT (2%) following posterior lumbar surgery and the potential complications of prophylactic anticoagulation, we continue to use intermittent pneumatic compression rather than elastic stockings for prophylaxis.