Optimal focusing by spatio-temporal inverse filter. I. Basic principles

A focusing technique based on the inversion of the propagation operator relating an array of transducers to a set of control points inside a medium was proposed in previous work [Tanter et al., J. Acoust. Soc. Am. 108, 223-234 (2000)] and is extended here to the time domain. As the inversion of the propagation operator is achieved both in space and time, this technique allows calculation of the set of temporal signals to be emitted by each element of the array in order to optimally focus on a chosen control point. This broadband inversion process takes advantage of the singular-value decomposition of the propagation operator in the Fourier domain. The physical meaning of this decomposition is explained in a homogeneous medium. In particular, a definition of the number of degrees of freedom necessary to define the acoustic field generated by an array of limited aperture in a focal plane of limited extent is given. This number corresponds to the number of independent signals that can be created in the focal area both in space and time. In this paper, this broadband inverse-focusing technique is compared in homogeneous media with the classical focusing achieved by simple geometrical considerations but also with time-reversal focusing. It is shown that, even in a simple medium, slight differences appear between these three focusing strategies. In the companion paper [Aubry et al., J. Acoust. Soc. Am. 110, 48-58 (2001)] the three focusing techniques are compared in heterogeneous, absorbing, or complex media where classical focusing is strongly degraded. The strong improvement achieved by the spatio-temporal inverse-filter technique emphasizes the great potential of multiple-channel systems having the ability to apply completely different signal waveforms on each transducer of the array. The application of this focusing technique could be of great interest in various ultrasonic fields such as medical imaging, nondestructive testing, and underwater acoustics.

Activity of LY333328 in experimental meningitis caused by a Streptococcus pneumoniae strain susceptible to penicillin

In a rabbit model of Streptococcus pneumoniae meningitis single doses of 10 and 2.5 mg of the glycopeptide LY333328 per kg of body weight reduced bacterial titers in cerebrospinal fluid (CSF) almost as rapidly as ceftriaxone at 10 mg/kg/h (changes in log CFU, -0.29 +/- 0.21 and -0.26 +/- 0.22 versus -0.34 +/- 0.15/ml/h). A dose of 1 mg/kg was bacteriostatic (change in log CFU, 0.01 +/- 0.11/ml/h). In two animals receiving LY333328 at a dose of 40 mg/kg the bacterial titers were reduced by 0.54 and 0.51 log CFU/ml/h. The penetration of CSF by LY333328 was 1 to 5%. The concentrations of lipoteichoic and teichoic acids in CSF and neuronal damage were similar in ceftriaxone- and LY333328-treated animals.

Yeast ERV2p is the first microsomal FAD-linked sulfhydryl oxidase of the Erv1p/Alrp protein family

Saccharomyces cerevisiae Erv2p was identified previously as a distant homologue of Erv1p, an essential mitochondrial protein exhibiting sulfhydryl oxidase activity. Expression of the ERV2 (essential for respiration and vegetative growth 2) gene from a high-copy plasmid cannot substitute for the lack of ERV1, suggesting that the two proteins perform nonredundant functions. Here, we show that the deletion of the ERV2 gene or the depletion of Erv2p by regulated gene expression is not associated with any detectable growth defects. Erv2p is located in the microsomal fraction, distinguishing it from the mitochondrial Erv1p. Despite their distinct subcellular localization, the two proteins exhibit functional similarities. Both form dimers in vivo and in vitro, contain a conserved YPCXXC motif in their carboxyl-terminal part, bind flavin adenine dinucleotide (FAD) as a cofactor, and catalyze the formation of disulfide bonds in protein substrates. The catalytic activity, the ability to form dimers, and the binding of FAD are associated with the carboxyl-terminal domain of the protein. Our findings identify Erv2p as the first microsomal member of the Erv1p/Alrp protein family of FAD-linked sulfhydryl oxidases. We propose that Erv2p functions in the generation of microsomal disulfide bonds acting in parallel with Ero1p, the essential, FAD-dependent oxidase of protein disulfide isomerase.

A mouse model of Streptococcus pneumoniae meningitis mimicking several features of human disease

The course of bacterial titers, meningeal inflammation, behavioral abnormalities, and neuronal damage was studied in a mouse model of Streptococcus pneumoniae meningitis. At 24 h after injection of 10(4) colony-forming units (CFU) S. pneumoniae into the right forebrain, infected mice became severely lethargic. Bacterial titers in cerebrospinal fluid and cerebellum rose to 10(9) CFU/ml, with strong granulocyte invasion into the meninges and neuronal necroses in the neocortex, striatum and hippocampal formation. Meningeal inflammation and neuronal damage in intercellular cell adhesion molecule-1- and macrophage colony-stimulating factor-deficient mice was similar to that in wild-type littermates. Untreated, the infection was fatal. Wild-type mice treated earlier than 24 h after infection with ceftriaxone (2 mg every 12 h for 3 days) survived without apparent behavioral abnormalities. Delay of treatment beyond 30 h led to the death of more than 50% of the infected mice. This mouse model is suitable for therapeutic studies and for the investigation of inflammation in knockout mice. The neuronal damage resembles morphological abnormalities observed in humans.

Organotypic hippocampal cultures. A model of brain tissue damage in Streptococcus pneumoniae meningitis

Hippocampal slices of newborn rats were exposed to either heat-inactivated Streptococcus pneumoniae R6 (hiR6) equivalent to 10(6) and 10(8) CFU/ml, lipoteichoic acid (LTA) (0.3 microg/ml and 30 microg/ml), peptidoglycans (PG) (0.3, 30, 50 and 100 microg/ml), pneumococcal DNA (pDNA) (0.3 and 30 microg/ml) or medium only (control). Cell injury was examined by Nissl staining, Annexin V and NeuN immunohistochemistry, and quantified by propidium iodide (PI) uptake and by determining neuron-specific enolase (NSE) concentration in the culture medium. Necrotic and apoptotic cell damage occurred in all treatment groups. Overall damage (Nissl and PI staining) was most prominent after hiR6 (10(8) CFU/ml), followed by LTA (30 microg/ml), pDNA (30 microg/ml), and not detectable after PG (30 microg/ml) exposure. PG (100 microg/ml) induced severe damage. Apoptotic cells were most frequent after exposure to LTA and hiR6. Damage in the neuronal cell layers (NeuN, NSE) was most severe after treatment with hiR6 (10(8) CFU/ml), followed by PG (100 microg/ml), pDNA (30 microg/ml), and LTA (30 microg/ml).

Leukocyte filtration in the early reperfusion phase on cardiopulmonary bypass reduces myocardial injury

Improved myocardial protection and cardiopulmonary bypass (CPB) have limited, but not abolished, intraoperative myocardial damage due to surgical reperfusion injury after release of the aortic crossclamp. In this double-blind, randomized study, we evaluated whether short-term leukocyte filtration during reperfusion may further reduce myocardial damage. Thirty-eight patients with coronary artery disease were randomly assigned to CPB with (group I; n = 19) or without leukocyte filtration (group II; n = 19). There was no difference in bypass time or crossclamp time between the groups. No patient in group I required catecholamines, whereas three patients in group II were supported with adrenaline or dobutamine on the first and second postoperative day. In addition, troponin T plasma levels were lower in group I (p < 0.05), whereas other markers for tissue injury (CK, CK-MB, LDH, S-GOT and S100B) did not differ. In conclusion, leukocyte filtration during reperfusion may further improve CPB by reducing myocardial damage.

Spatial memory and learning deficits after experimental pneumococcal meningitis in mice

Survivors of bacterial meningitis frequently suffer from long-term sequelae, particularly from learning and memory deficits. For this reason, spatial memory and learning was studied in a mouse model of ceftriaxone-treated Streptococcus pneumoniae meningitis. Persistent deficits of spatial learning despite normal motor function were observed in mice infected with 10(4) colony-forming units (CFU) in 25 microl of saline into the right forebrain in comparison to mice treated with an equal amount of saline. Survivors of meningitis performed significantly worse in memorizing a hidden platform in a Morris water maze. After 2 weeks, the difference between post-meningitis and control mice diminished. Yet, when the platform was moved after 180 days, learning of the new location was still strongly impaired in mice surviving meningitis.

The effect of changing stimulus intensities on median nerve somatosensory-evoked potentials

We investigated median nerve somatosensory-evoked potentials (SEP) in 31 healthy volunteers to test the hypothesis that 1) increasing stimulus intensity influences SEP components in both amplitude and latency 2) SEP components respond differently to changing intensities. Cluster analysis and analysis of variance were used for statistical testing. Three groups of components could be found according to latency changes in response to increasing stimulus intensities: N13, and P15, the primary cortical response (N19, P22) and the components over 30 ms. In general, SEP components below 30 ms significantly shortened in latency and increased in amplitude with subsequent saturation. In contrast, in components over 30 ms latencies decreased linearly and amplitudes changed inhomogeneously. The clear effect of stimulus intensity on most median nerve SEP components makes it necessary to maintain comparable stimulus intensities when comparing intra- and interindividual registrations.

Follistatin (FS) in human cerebrospinal fluid and regulation of FS expression in a mouse model of meningitis

OBJECTIVE

Follistatin (FS) is the specific binding protein of activin and expression of both factors is regulated by inflammatory agents. Therefore, FS concentrations were determined in cerebrospinal fluid (CSF) of patients with bacterial and viral meningitis or multiple sclerosis (MS), as well as in the CSF of patients without meningial inflammation or autoimmune diseases. Furthermore, a mouse pneumococcal meningitis model was used to localise the cellular sources of FS in brains of normal and meningitic mice.

METHODS

FS concentrations in CSF were determined by ELISA; FS in mice was localised by in situ hybridisation and immunohistochemistry.

RESULTS

FS concentrations were > or =0.4 microg/l in 22 of 66 CSF samples of meningitis patients versus 2 of 27 CSF samples from patients with multiple sclerosis (P<0.05) and 2 of 41 CSF specimen from patients without neuroinflammatory diseases (P<0.01). In the CSF of patients with meningitis, the concentration of FS was correlated with total protein (P<0.005) and lactate concentrations (P<0.05), but not with leukocyte counts, interval between onset of disease and CSF analysis, or clinical outcome. The CSF-to-serum ratios of FS and albumin also correlated significantly (P<0.0005). In some patients with meningitis the CSF-to-serum ratios suggested that the elevated FS in CSF did not originate from serum alone. FS was localised in mice brains to neurones of the hippocampus, dentate gyrus, neocortex, and to the choroid plexus. Analyses of brains and other organs from uninfected and infected animals sacrificed 6-36 h after infection did not reveal any obvious differences in the distribution and intensity of FS mRNA and protein expression.

CONCLUSIONS

The concentration of FS in humans is elevated during meningitis. In some patients the increase is caused by a release of FS from brain into CSF. Data from the mouse meningitis model suggest that increased CSF concentrations of FS in meningitis appear not to be accompanied by an elevated number of cells containing FS mRNA or protein in the brain.

CT and arteriography in the evaluation of indirect myocardial revascularization with a free-muscle transplant: initial experience

PURPOSE

To examine patients with advanced cardiovascular disease with radiology after indirect myocardial revascularization with a free-skeletal-muscle transplant and to determine whether the attached vessel remains patent over the middle and long terms.

MATERIALS AND METHODS

In 10 patients with advanced, inoperable cardiovascular disease treated with indirect myocardial revascularization with a free-muscle transplant, radiologic follow-up was performed postoperatively and every 6 months. All 10 patients underwent selective arteriography of the anastomosed vessel and contrast material-enhanced helical computed tomography (CT) (transverse sections and reconstructions).

RESULTS

All patients showed adequate vascular conditions postoperatively, as did nine of 10 patients after 1 year. In one patient, the anastomosed artery was occluded. CT showed time-dependent muscle degeneration in all patients. Postoperative, contrast-enhanced, superselective CT showed an area of high-attenuating uptake in the muscle transplant in all patients. After 1 year, CT depicted perfusion defects of the skeletal muscle in two patients. In eight patients, however, small vascular bridges from the skeletal muscle to the myocardium were detected. Radiologic results correlated well with clinical outcome and stress electrocardiograms.

CONCLUSION

Helical intraarterial CT and arteriography were sensitive in depicting enhancement and remaining vital function in nine of 10 patients after indirect myocardial revascularization with a free-muscle transplant. This combination seems promising for postoperative examination in such patients.

Rifampin reduces production of reactive oxygen species of cerebrospinal fluid phagocytes and hippocampal neuronal apoptosis in experimental Streptococcus pneumoniae meningitis

Bacterial compounds induce the production of reactive oxygen species (ROS) in meningitis. Rifampin releases smaller quantities of proinflammatory compounds from Streptococcus pneumoniae than do beta-lactam antibiotics. Therefore, rabbits infected intracisternally with S. pneumoniae were treated intravenously either with rifampin 5 mg/kg/h or ceftriaxone 10 mg/kg/h (n=9 each). Before initiation of antibiotic treatment, a strong positive correlation between ROS production of cerebrospinal fluid (CSF) phagocyte populations and bacterial CSF titers was observed (granulocytes: rs=.90, P<.0001; monocytes: rs=.81, P<.0001). CSF leukocytes from rifampin-treated rabbits produced less ROS (monocytes at 2 h after initiation of treatment: P=.045; at 5 h: P=.014; granulocytes at 5 h: P=.036) than did leukocytes from animals receiving ceftriaxone. The CSF malondialdehyde concentrations and the density of apoptotic neurons in the dentate gyrus were lower in rifampin- than in ceftriaxone-treated animals (P=.002 and.005). The use of rifampin to reduce the release of ROS and to decrease secondary brain injury appears promising.

[Comparison of cathepsin-B-like activity and CA 125 assays use in ovarian cancer diagnosis]

BACKGROUND

Determination of serum cathepsin B-like activity was used as a diagnostic marker of ovarian cancer. The aim of this study was to compare its diagnostic utility with CA 125 assay.

METHODS

In 50 patients with epithelial ovarian cancer and 20 with ovarian cyst cathepsin B-like activity by fluorimety and CA 125 concentration by luminiscence immunoassay, were determined. The obtained results were compared by two cut-off values computed from the data obtained in healthy controls and ovarian cysts (cathepsin B: 11 and 108 mU/ml; CA 125: 35 and 135 U/ml), respectively.

RESULTS

In differential diagnosis between ovarian carcinomas and ovarian cysts cathepsin B shows similar specificity (95%) as CA 125 but higher sensitivity (63.5% vs 50%). Both cathepsin B and CA 125 are good predictors of tumour response and recurrence

CONCLUSIONS

Adding CA 125 determination to cathepsin B-like activity in the laboratory diagnostics of ovarian cancer increased the sensitivity and positive predictive values as compared to the use of cathepsin B alone.

Contrast-enhanced transcranial color-coded duplexsonography in stroke patients with limited bone windows

BACKGROUND AND PURPOSE

Thickening of the temporal bone in stroke-age patients may obviate sonographic evaluation of the circle of Willis in 20% to 30% of patients. We assessed the diagnostic efficacy of contrast-enhanced transcranial color-coded duplexsonography (TCCD) for noninvasive evaluation of the circle of Willis in stroke patients with limited bone windows.

METHODS

Of 171 consecutive patients who presented with ischemic symptoms in the middle cerebral artery (MCA) territory, 49 patients (32 female, 17 male; age range, 70.5+/-10.6 years) had no detectable colorflow signals from the circle of Willis by TCCD because of limited acoustic windows. These 49 patients received an IV injection of a sonographic contrast-enhancing agent, Levovist (Schering; Berlin, Germany), and were re-examined. Correlative imaging studies of the circle of Willis were obtained in 42 of 49 of these patients.

RESULTS

In 38 of 49 patients, contrast-enhanced TCCD enabled full visualization of the circle of Willis bilaterally; in an additional five patients, contrast-enhanced TCCD revealed only the portion of the circle of Willis ipsilateral to the probe through one temporal bone. In six of these 43 patients, contrast-enhanced TCCD showed MCA stenosis and MCA occlusion in three; three of the six cases of MCA stenosis and all three cases of the MCA occlusion were found on the symptomatic side. In six of 49 patients, no colorflow signals were obtained after contrast enhancement. All contrast-enhanced TCCD findings were confirmed by CT angiography, transfemoral digital subtraction angiography, MR angiography, or a combination of all three correlative studies. Levovist produced no serious adverse events.

CONCLUSION

In stroke-age patients with limited acoustic windows, contrast-enhancement with Levovist can markedly increase the sensitivity of TCCD and increase the detection of clinically relevant intracranial arterial disease.

Gemifloxacin is effective in experimental pneumococcal meningitis

In a rabbit model of Streptococcus pneumoniae meningitis, 5 mg of gemifloxacin mesylate (SB-265805) per kg/h reduced the bacterial titers in cerebrospinal fluid (CSF) almost as rapidly as 10 mg of ceftriaxone per kg/h (Deltalog CFU/ml/h +/- standard deviation [SD], -0.25 +/- 0.09 versus -0.38 +/- 0.11; serum and CSF concentrations of gemifloxacin were 2.1 +/- 1.4 mg/liter and 0.59 +/- 0.38 mg/liter, respectively, at 24 h). Coadministration of 1 mg of dexamethasone per kg did not affect gemifloxacin serum and CSF levels (2.7 +/- 1.4 mg/liter and 0.75 +/- 0.34 mg/liter, respectively, at 24 h) or activity (Deltalog CFU/ml/h +/- SD, -0.26 +/- 0.11).

Stringent tests of shell model calculations in fp shell nuclei (46, 48)Ti and (50,52)Cr from measurements of g factors and B(E2) values

Measurements of magnetic moments and lifetimes of 2(+)(1) and 4(+)(1) states of (46,48)Ti and (50,52)Cr were performed with high accuracy via projectile Coulomb excitation and the technique of transient magnetic fields. The high quality of the data allows for the first time to establish stringent constraints on large scale shell model calculations. Whereas the global behavior of the data is well explained by full fp shell model calculations, distinct deviations in the g factors and B(E2) values of (46,48)Ti from theoretical predictions can be attributed to excitations of the 40Ca core. This suggestion is supported by recent Monte Carlo calculations which provide evidence that 48Ca is a better inert core.

Serum haptoglobin, CA 125 and interleukin 6 levels in malignant and non-malignant tumors of the ovary

In sera of women with malignant and non-malignant ovarian tumors, concentrations of the following proteins were determined: haptoglobin, measured by the reactions either with hemoglobin (Hp-Hb) or with concanavalin A (Hp-Con A), CA 125 antigen and interleukin 6 (IL-6). Besides preoperative data, obtained from all the patients and the group of healthy women, in the patients with ovarian cancer (III/IV FIGO stages) effects of administration of cytostatics were measured by monitoring changes in the levels of the examined parameters through the course of the therapy. All the results were submitted to statistical evaluation which showed differences and correlations among definite groups (normal/non-malignant, normal/cancers, non-malignant/cancers). Similar results were obtained for Hp-Hb and CA 125 determination. Moreover, a correlation between haptoglobin level and age was found. Patterns of monitoring revealed a surprising absence of Hp-Con A interaction in some cases.

Noninvasive assessment of the circle of Willis in cerebral ischemia: the potential of CT angiography and contrast-enhanced transcranial color-coded duplexsonography

Thirty-four patients with acute hemispheric ischemic strokes underwent both CT angiography and contrast-enhanced transcranial color-coded duplexsonography (TCCD) to study the effectiveness of the combined noninvasive techniques for evaluation of the circle of Willis. In 3/34 patients, CT angiography and contrast-enhanced TCCD demonstrated middle cerebral artery (MCA) occlusion, in 5 others MCA stenosis. A severe posterior cerebral artery stenosis was missed by CT angiography. In 8 patients, contrast-enhanced TCCD failed because of poor bone windows. In these patients, CT angiography was normal. CT angiography and contrast-enhanced TCCD are complementary noninvasive diagnostic tools. Disagreements between the diagnostic findings of these methods still need further evaluation by digital subtraction angiography.

Photodynamic treatment of epithelial tissue derived from patients with endometrial cancer: a contribution to the role of laminin and epidermal growth factor receptor in photodynamic therapy

Photodynamic therapy (PDT) was used to treat endometrial G1 cancer tissue derived from patients who had undergone a total hysterectomy and bilateral salpingo-oophorectomy. After surgical treatment the cancerous tissue was kept in a medium containing Dulbecco solution, fetal calf serum, and antibiotics. The tissue was then exposed to hematoporphyrin derivative (0.1 mg/ℓ) and 24 h later exposed to light (total light dose-18 J/sq cm). Necrosis depth was evaluated 24 h later using a light microscope. In order to assess the possible role of the basal membrane component laminin, as well as epidermal growth factor receptor susceptibility to PDT, immunohistochemical studies were carried out. Additionally, nucleolar organizer regions evaluation was performed. Our experiment confirmed that PDT results in the necrosis in the treated endometrial cancer, while not affecting the laminin in the cancerous tissue. In contrast, PDT strongly affects the epidermal growth factor receptor and nucleolar organizer regions in cancer cells. We suggest that laminin may contribute to the prevention of cancer dissemination in the cases where PDT has to be repeated, and that after PDT the cells become less susceptible to a mitogen, like, e.g., epidermal growth factor. © 1999 Society of Photo-Optical Instrumentation Engineers.

Rifampin reduces early mortality in experimental Streptococcus pneumoniae meningitis

Compared with beta-lactam antibiotics, rifampin releases smaller quantities of proinflammatory cell wall products from Streptococcus pneumoniae in vitro. Mice infected intracerebrally with S. pneumoniae were treated subcutaneously with 2-mg doses of rifampin or ceftriaxone (n=43 each) every 12 h for 3 days and then observed for another 3 days. Rifampin reduced overall mortality from 49% to 26% (P=.04). Kaplan-Meyer analysis revealed a substantial reduction of mortality during the first 24 h in mice receiving rifampin (difference in survival time: P=.007). Eight h after receiving a single 2-mg dose of rifampin or ceftriaxone, rifampin-treated mice had lower serum and cerebrospinal fluid concentrations of lipoteichoic and teichoic acids than did ceftriaxone-treated mice (median serum level: <0.5 vs. 27.0 ng/mL, P=.02; median cerebrospinal fluid level of pooled specimens: 97.5 vs. 206.0 ng/mL). Thus, the use of rifampin appears promising for reducing the release of proinflammatory bacterial components and decreasing early mortality in bacterial meningitis.

Lumbar and ventricular CSF protein, leukocytes, and lactate in suspected bacterial CNS infections

Protein concentration, leukocyte density, and lactate concentration were studied in 41 pairs of ventricular and lumbar CSF drawn at an interval of less than 24 hours from patients with suspected bacterial CNS infections. The ventriculo-lumbar ratios ranged from 0.003 to 10.2 (median=0.42) for protein and from 0.002 to 53.5 (median=0.17) for leukocytes. The uneven distribution of leukocytes and proteins in the CSF space may produce findings that fail to indicate bacterial CNS infections. Lactate was distributed more homogeneously in the CSF space than protein and leukocytes (ventriculo-lumbar ratio 0.52 to 1.66 [median=0.811).

Contributions of pathway and neuron to preferential motor reinnervation

Motor axons regenerating after transection of mixed nerve preferentially reinnervate distal muscle branches, a process termed preferential motor reinnervation (PMR). Motor axon collaterals appear to enter both cutaneous and muscle Schwann cell tubes on a random basis. Double-labeling studies suggest that PMR is generated by pruning collaterals from cutaneous pathways while maintaining those in motor pathways (the "pruning hypothesis"). If all collaterals projecting to muscle are saved, then stimulation of regenerative sprouting should increase specificity by increasing the number of motoneurons with at least one collateral in a muscle pathway. In the current experiments, collateral sprouting is stimulated by crushing the nerve proximal to the repair site before suture, a maneuver that also conditions the neuron and predegenerates the distal pathway. Control experiments are performed to separate these effects from those of collateral generation. Experiments were performed on the rat femoral nerve and evaluated by exposing its terminal cutaneous and muscle branches to HRP or Fluoro-Gold. Crush proximal to the repair site increased motor axon collaterals at least fivefold and significantly increased the percentage of correctly projecting motoneurons, consistent with the pruning hypothesis. Conditioning the nerve with distal crushes before repair had no effect on specificity. A graft model was used to separate the effects of collateral generation and distal stump predegeneration. Previous crush of the proximal femoral nerve significantly increased the specificity of fresh graft reinnervation. Stimulation of regenerative collateral sprouting thus increased PMR, confirming the pruning hypothesis. However, this effect was overshadowed by the dramatic specificity with which predegenerated grafts were reinnervated by fresh uncrushed proximal axons. These unexpected effects of predegeneration on specificity could involve a variety of possible mechanisms and warrant further study because of their mechanistic and clinical implications.

Granulocytes in the subarachnoid space of humans and rabbits with bacterial meningitis undergo apoptosis and are eliminated by macrophages

The contribution of leukocyte apoptosis to the resolution of meningeal inflammation in bacterial meningitis was studied in the cerebrospinal fluid (CSF) and in meningeal infiltrates of humans and rabbits by in situ tailing, flow cytometry, agarose gel electrophoresis, and electron microscopy. In humans, the rate of apoptotic granulocytes was 21.0+/-20.8% (n=11) in cytocentrifuge preparations and 3.3+/-3.4 (n=14) in putrid infiltrates of autopsy cases (P=0.02). In rabbits, CSF pleocytosis peaked 8 h after the initiation of antibiotic treatment (5311+/-3122/microl). At this time, the rate of apoptotic granulocytes was 15.2+/-7.3% in CSF and 1.8+/-1.4% in the meningeal infiltrates (each group n=6, P=0.007). Thereafter, the rate of apoptotic granulocytes in CSF declined below 10%. In humans and rabbits, bands representing internucleosomal fragments of approximately 180 base pairs and multiples thereof were documented on agarose gels. Phagocytosis of apoptotic granulocytes by macrophages was visualized by light and electron microscopy. In conclusion, during resolution of subarachnoid space inflammation in bacterial meningitis, a substantial fraction of granulocytes undergoes apoptosis. These granulocytes are removed by phagocytosis by macrophages. Apoptosis is more frequent in granulocytes floating in the CSF than in adherent cells.

[Dependence of serous activity of cathepsin B on histological types of ovarian carcinomas]

The preoperative activity of cathepsin B was determined in the serum of 110 patients with primary ovarian carcinomas and in 35 women with benign ovarian tumor. The significant increase of cathepsin B activity in ovarian carcinomas is independent of its types in comparison to benign ovarian tumor. The percentage of the results with value above the cut-off values was the highest for serous types of ovarian carcinomas. The dependence between the increase of cathepsin B activity and the FIGO stage of the disease was observed only for serous and endometrioid type of ovarian carcinomas.

A brain image database for structure/function analysis

BACKGROUND AND PURPOSE

Lesion-deficit-based structure-function analysis has traditionally been empirical and nonquantitative. Our purpose was to establish a new brain image database (BRAID) that allows the statistical correlation of brain functional measures with anatomic lesions revealed by clinical brain images.

METHODS

Data on 303 participants in the MR Feasibility Study of the Cardiovascular Health Study were tested for lesion/deficit correlations. Functional data were derived from a limited neurologic examination performed at the time of the MR examination. Image data included 3D lesion descriptions derived from the MR examinations by hand segmentation. MR images were normalized in-plane using local, linear Talairach normalization. A database was implemented to support spatial data structures and associated geometric and statistical operations. The database stored the segmented lesions, patient functional scores, and several anatomic atlases. Lesion-deficit association was sought by contingency testing (chi2-test) for every possible combination of each neurologic variable and each labeled atlas structure. Significant associations that confirmed accepted lesion-deficit relationships were sought.

RESULTS

Two-hundred thirty-five infarctlike lesions in 117 subjects were viewed collectively after mapping into Talairach cartesian coordinates. Anatomic structures most strongly correlated with neurologic deficits tended to be situated in anatomically appropriate areas. For example, infarctlike lesions associated with visual field defects were correlated with structures in contralateral occipital structures, including the optic radiations and occipital gyri.

CONCLUSION

Known lesion-deficit correlations can be established by a database using a standard coordinate system for representing spatial data and incorporating functional and structural data together with appropriate query mechanisms. Improvements and further applications of this methodology may provide a powerful technique for uncovering new structure-function relationships.

Training environment for inferior vena caval filter placement

This paper describes a Virtual Environment system designed to aid in training interventional radiologists in inferior vena cava filter placement. It is being developed as part of a VE simulator for a number of surgical and interventional radiology procedures at the Laboratory for Advanced Computer Applications in Medicine at the George Washington University. In this procedure a filter is placed in the inferior vena cava to prevent blood clots from the lower portion of the body from reaching the lungs and causing a pulmonary embolus. The simulation is designed to provide both tutorial and testing modes for the filter placement procedure.

Implementing quality assurance programs in multigroup practices for treating hypercholesterolemia in patients with coronary artery disease

Healthcare reform is driving the development of specialty physician practices into larger regional and national physician networks. These networks arise from the federation of > or =2 practices that negotiate with managed-care organizations for contracts. Developing cardiovascular networks and establishing and implementing lipid management quality assurance programs into the network are presented in this article. Goals of the lipid management program include enhancing the identification, diagnosis, education, and comprehensive treatment of patients with cardiovascular disease. Utilizing an integrated, coordinated, multidisciplinary approach to lipid management allows the cardiology network to improve patients' quality of life, reduce long-term costs, and gain a competitive advantage for successful contracting. A network lipid management program involves targeting eligible patients and treating them to a targeted level for low-density lipoprotein (LDL) cholesterol where possible. Among cardiologists, there is a consensus that achieving an LDL cholesterol of < 100 mg/dL for patients with pre-existing cardiovascular disease is desirable. Secondary lipid management program goals include: (1) collecting, storing, and analyzing patient demographics; (2) implementing programs involving lifestyle modification, smoking cessation, weight control; and (3) measuring clinical and economic outcomes. Convergence of several driving forces in managing hypercholesterolemia provides cardiologists with the ability to improve the process. These forces include: market-consolidated delivery systems, established lipid management guidelines, and employer-initiated policies requiring higher quality care within managed-care organizations. Methods to achieve enhanced treatment effectiveness, patient satisfaction, and control costs are discussed. Utilizing multidisciplinary teams including nurse case managers, clinical pharmacists, dietitians, and physician assistants to achieve lipid level goals and for nutritional counseling is desirable. Developing disease state management programs, treatment algorithms, databases with analytic reports, and process improvement across the network is of paramount importance for future progress and success.

Clinical and pathological characterization of northern elephant seal skin disease

From 1984 through 1992, staff at The Marine Mammal Center (TMMC, Sausalito, California, USA) examined 207 northern elephant seals (Mirounga angustirostris) with a condition of unknown etiology called northern elephant seal skin disease (NESSD). The skin lesions were characterized by patchy to extensive alopecia and hyperpigmentation, punctate or coalescing epidermal ulceration, and occasionally, massive skin necrosis. Microscopic lesions included ulcerative dermatitis with hyperkeratosis, squamous metaplasia and atrophy of sebaceous glands. All diseased seals were less than 2 years of age and suffered from emaciation, depression, and dehydration. Mortality from septicemia increased significantly with severity of skin ulceration. Compared to 14 apparently unaffected seals, diseased seals had depressed levels of circulating thyroxine, triiodothyronine, retinol, serum iron, albumin, calcium, and cholesterol. Levels of alanine aminotransferase, aspartate aminotransferase, lactate dehydrogenase, gamma glutamyl transpeptidase, blood urea nitrogen, and uric acid were elevated. Morphometrically, diseased animals were approximately 15% smaller than normal seals of the same sage. Serum and blubber concentrations of 36 polychlorinated biphenyl congeners (sigma PCB) and dichloro-diphenyl-dichloroethylene (p,p'-DDE) were negatively correlated with body mass. Mean concentrations of sigma PCB and p,p'-DDE in serum in diseased seals were elevated as compared to apparently normal seals. Etiology of this syndrome remains unknown, but the possibility of PCB toxicosis cannot be ruled out.

Cathepsin B-like activity as a serum tumour marker in ovarian carcinoma

Serum cathepsin B-like activity was determined in 75 patients with ovarian carcinomas and in control groups. Ovarian cancers were of FIGO stages I-IV. Control groups consisted of 15 healthy women, 20 patients with myomas of the uterus, and 17 with benign ovarian cysts. Preoperative results showed elevated cathepsin B-like activity in 100% of the patients with ovarian cancers in relation to healthy subjects and patients with myomas, and in 78% in relation to benign ovarian cysts. Cathepsin B activity increased progressively with the FIGO stage of the disease, but the differences among particular stages were not statistically significant. In serous tumours cathepsin activity was significantly higher only in comparison to endometrioid ones (p < 0.001). Antipapain capacity of cystatins in the sera was also determined. No significant correlation between cathepsin B-like, and antipapain activity of cystatins was found. Serum cathepsin B-like activity may be helpful in the preoperative differential diagnosis between ovarian carcinomas and benign ovarian or uterine tumours.

The activities and subcellular localization of cathepsin B and cysteine proteinase inhibitors in human ovarian carcinoma

Ovarian carcinomas exhibited a higher cathepsin B activity than did normal ovaries. The plasma membrane fractions of ovarian cancers were enriched in the activities of both cathepsin and cysteine proteinase inhibitors. The ratio of cathepsin to the inhibitors in these fractions was higher at stage IV than at stage III of the disease, classified according to the Federation of International Gynecology and Obstetrics.

The effect of aging on the utilization of chemotherapy for metastatic breast cancer: a population-based study

Older women (i.e., > or = 65 years of age) receive less adjuvant chemotherapy than younger women, in part because chemotherapy has been less effective in postmenopausal than premenopausal women in clinical trials. Metastatic breast cancer, however, does not respond differently to chemotherapy by age. Therefore, to evaluate further the effect of age on chemotherapy utilization, we conducted a population-based study of the treatment of metastatic breast cancer. Patients (n = 132) were identified by cross-tabulating death certificates from 1984 to 1991 with breast cancer cases in the Washington County Cancer Registry. Treatment information was obtained from the Tumor Registry of the Washington Country Hospital and Hospital medical records. Forty patients (74%) < 65 years old received chemotherapy compared to 11 (42%) 65-74 and 6 (12%) > or = 75 (p < 0.0001). Adjusting for other medical conditions and whether or not the patient saw a medical oncologist, there was still a significant effect of age in patients > or = 75 (p < 0.001) and a trend (p = 0.17) for patients 65-74. The different patterns of chemotherapy utilization were not associated with survival differences. Radiation therapy was also utilized significantly less frequently in older than younger patients, but the age effect was not as pronounced as with chemotherapy. There was no age effect on the utilization of hormonal therapy. Less frequent utilization of chemotherapy in older patients is probably caused by a combination of patient and physician factors and may result in less effective palliation for older patients.

The activities and subcellular localization of cathepsin B and cysteine proteinase inhibitors in human ovarian carcinoma

Ovarian carcinomas exhibited a higher cathepsin B activity than did normal ovaries. The plasma membrane fractions of ovarian cancers were enriched in the activities of both cathepsin and cysteine proteinase inhibitors. The ratio of cathepsin to the inhibitors in these fractions was higher at stage IV than at stage III of the disease, classified according to the Federation of International Gynecology and Obstetrics.

nm23 expression in tissue sections and tumor effusion cells of ovarian neoplasms

The genetic changes involved in the metastatic process of ovarian epithelial cancer remain undetermined. The expression of nm23, a putative metastasis-suppressor gene product, was assessed immunohistochemically in malignant and benign ovarian neoplasms, considering histology of tumors and clinical advancement of disease. Comparison of nm23 protein content in tissue sections and respective cyst and/or ascitic fluid cells was also performed. Significant heterogeneity of nm23 immunostaining was observed, and no correlation with histological subtype of ovarian carcinoma was found. Expression of nm23 was higher in carcinomas compared with benign tumors. A significant trend to have a higher nm23 reactivity in ascitic fluid cells vs. primary tumors was observed. Our results indicate that the increase of nm23 reactivity is activated in the early stages of the disease and that the progression of ovarian carcinoma is accompanied by overexpression of nm23 protein. Our observations did not confirm the postulated role of nm23 as a suppressor gene in ovarian cancer.

Anti-inflammatory treatment influences neuronal apoptotic cell death in the dentate gyrus in experimental pneumococcal meningitis

Apoptotic neuronal death and the increase of neuron-specific enolase (NSE) in cerebrospinal fluid (CSF) were studied in a rabbit model of experimental pneumococcal meningitis after treatment with antimicrobial (ceftriaxone) and antiinflammatory agents (dexamethasone, monoclonal antibodies against the beta-subunit of beta 2-integrins [anti-CD18 mAb]). Twenty-four hours after infection, apoptotic cell death was found solely in the granular cell layer of the dentate gyrus. Neurons with DNA fragmentation were quantified with the in situ tailing (IST) reaction. Dexamethasone and anti-CD18 mAb inhibited the NSE increase in CSF significantly (p = 0.003, p = 0.011). After administration of dexamethasone the density of apoptotic neurons was significantly higher than in control animals receiving only ceftriaxone (p = 0.044). The median of the density of apoptotic neurons was lower in the dentate gyrus in animals receiving anti-CD18 mAb and ceftriaxone vs those receiving only ceftriaxone, although the difference did not reach statistic significance (p = 0.058). In conclusion, apoptotic cell death occurs in the dentate gyrus during the early phase of bacterial meningitis. The extent was influenced by antiinflammatory therapy. The systemic administration of glucocorticoids increased the quantity of apoptotic neurons in the dentate gyrus but reduced overall neuronal damage as indicated by low levels of NSE concentration in CSF.

Expression of p53 protein and Ki-67 reactivity in ovarian neoplasms. Correlation with histopathology

The expression of Ki-67 proliferation antigen and its relation to p53 protein was assessed immunohistochemically in malignant and benign ovarian neoplasms, considering the stage of disease and histology of tumors. The comparison of p53 and Ki-67 in tissue sections and respective cyst and/or ascitic fluid cells was also performed. Significant heterogeneity of staining was observed. However, the relationship between p53 and Ki-67 activity in tissue sections and loose cells in individual patients was evident. Moreover, the presence of Ki-67 antigen was closely correlated with p53 protein. It was observed the trend for serous carcinoma to have a higher Ki-67 and p53 positivity versus endometrioid and mucinous carcinomas. However, it was not statistically significant. Both growth fraction as measured by Ki-67 staining and p53 content were significantly higher in stages III and IV compared to stages I and II of ovarian carcinomas (P<.05, and P<.01, respectively). In benign ovarian neoplasms, no p53 reactivity was observed and Ki-67 staining was very low. Our results showed that p53 is not a feature of benign epithelial ovarian tumors and indicate that increased proliferative activity of cells seems to involve immunohistochemically detectable alterations in p53 gene contributing to the evolution of ovarian carcinoma.

Measurements of haptoglobin by the reaction with concanavalin A in sera of patients with ovarian tumours

The concentration of haptoglobin in sera of healthy women and patients with non-malignant and malignant ovarian tumours was measured by two methods, i.e. complex formation with haemoglobin and complex formation with concanavalin A. High correlation (r = 0.74) between both the methods was found in the group of healthy women, but correlation coefficients were much lower in the group of non-malignant and malignant tumours (r = 0.42 and 0.37, respectively). Direct determinations of haptoglobin, and calculation of the ratio of haptoglobin bound to concanavalin A to haptoglobin bound to haemoglobin revealed statistically significant differences among the examined groups. Comparison of two methods of haptoglobin quantitation suggest that processes connected with ovarian disorders may alter the glycosylation of haptoglobin oligosaccharide chains.

The effect of age on the beta-adrenergic lipolytic response in healthy humans

We evaluated the effect of age on the lipolytic response to intravenous infusion of isoproterenol in 12 elderly (age, > 60 years) and 12 young (age, 21 to 34 years) volunteers to examine if there is alteration in innervated beta-adrenergic responsiveness in tissues other than the heart. Lipolysis was evaluated by measuring the plasma concentrations of free fatty acids and glycerol. We also measured the plasma concentration of isoproterenol during infusion so that we could calculate comparable plasma isoproterenol concentrations to lipolytic responses in the two age groups. Our data show that, at equivalent infusion rates of isoproterenol, the two age groups achieved equivalent isoproterenol concentrations. The elderly had a higher concentration of free fatty acids but equivalent concentrations of glycerol as compared with the young subjects at equivalent isoproterenol plasma concentrations. However, our data were complicated by the fact that at the higher infusion rates of isoproterenol, the elderly showed a greater sympathetic stimulation than the young subjects as measured by plasma norepinephrine concentrations. Nonetheless, our data could not show that the elderly subjects were more resistant to beta-adrenergic receptor-mediated stimulated lipolysis. Thus innervated beta-adrenergic receptor hyporesponsiveness caused by aging may not necessarily extend to all organ systems.

[Intraoperative recording of intramedullary pressures with a microprobe]

The implantation of femoral prostheses and intramedullary nailing for fracture stabilisation are well-established techniques in traumatology. Nevertheless, the obvious biomechanical advantages of intramedullary splinting are partly offset by occasional disturbances of pulmonary circulation and function. These disorders of pulmonary function are apparently correlated with an operation-induced increase in intramedullary pressure. A simple, low-invasive and reliable system for the measurement of intramedullary pressure is presented. The heart of the system is a microtip probe that converts changes in pressure into electrical impulses, which are then filtered and amplified in the pressure measuring system (PMS).

The microtip intramedullary probe for intraoperative pressure measurement

The implantation of femoral stem prostheses and intramedullary fracture stabilisation are well-established techniques in traumatology. Although the biomechanical advantages of intramedullary splinting are obvious, impairments of pulmonary circulation and respiratory function are typical and feared complications. These pulmonary disturbances are strikingly correlated with operation-induced intramedullary hypertension. A simple, low-invasive and reliable system for the measurement of intramedullary pressure is presented. At the heart of the system is a microtip probe, transforming changes of pressure into electric impulses, filtered and amplified in a pressure measuring system (PMS).

[Diagnostic value of determining alpha1 protease inhibitor and alpha2 macroglobulin in the serum of women with malignant and non-malignant ovarian tumors and uterine myomas]

In the serum of 21 women with malignant ovarian tumours, 13 with uterine myomas and 16 with cysts the concentrations were determined of alpha 1 inhibitor of proteases and alpha 2 macroglobulin by immunodiffusion, and the functional activity of both inhibitors which made possible calculation of the specific activity (units of inhibitory activity per one gram of inhibitor protein). In women with malignant tumours the specific activity of alpha 1 inhibitor was decreased, suggesting that a part of the inhibitor was functionally inactive. This decrease was statistically significant in relation to the control group and the groups of myomas and cysts, but was independent of the degree of disease progression. The specific activity of alpha 2 macroglobulin was significantly decreased only in patients with grade IV degrees of clinical progression (according to FIGO) in relation to the control group and to the group with cysts.

[Use of partusisten in cases of placenta praevia and the incidence of respiratory distress syndrome in newborn infants]

Partusisten (Th 1165a, fenoterol) was given to 40 pregnant women aged from 19 to 39 years in whom ultrasonography demonstrated placenta praevia. Bleeding occurred between 21 and 36 weeks of pregnancy. The control group consisted of 44 pregnant women aged from 21 to 43 years not treated with partusisten. Bleeding in this group developed between 22 and 40 weeks of pregnancy. The authors conclude that partusisten use in cases of bleeding from placenta praevia in adequate doses and at adequate time make possible prolongation of pregnancy duration which increases the progression of lung maturation in the fetus and enabling reaching of relative biological maturity. This reduces the incidence of neonatal respiratory distress syndrome, and is the method of choice if genital bleeding develops prior to the 32nd week of pregnancy.

T-lymphocyte colony formation of murine thymocytes in agar contained in glass capillaries

Optimal growth conditions are presented for a new colony test with mouse thymocytes in agar contained in glass capillaries. The kinetics of colony growth and the dependence from the PHA-, I1-2-, agar- and 2-mercaptoethanol concentration are shown. The colony forming cells are identified as T-lymphocytes by usual morphology and by an indirect immunoperoxidase method using mouse anti-Thy 1.2 antibodies.