Separability of calcium slow waves and functional connectivity during wake, sleep, and anesthesia

Modulation of brain state, e.g., by anesthesia, alters the correlation structure of spontaneous activity, especially in the delta band. This effect has largely been attributed to the ∼ 1    Hz slow oscillation that is characteristic of anesthesia and nonrapid eye movement (NREM) sleep. However, the effect of the slow oscillation on correlation structures and the spectral content of spontaneous activity across brain states (including NREM) has not been comprehensively examined. Further, discrepancies between activity dynamics observed with hemoglobin versus calcium (GCaMP6) imaging have not been reconciled. Lastly, whether the slow oscillation replaces functional connectivity (FC) patterns typical of the alert state, or superimposes on them, remains unclear. Here, we use wide-field calcium imaging to study spontaneous cortical activity in awake, anesthetized, and naturally sleeping mice. We find modest brain state-dependent changes in infraslow correlations but larger changes in GCaMP6 delta correlations. Principal component analysis of GCaMP6 sleep/anesthesia data in the delta band revealed that the slow oscillation is largely confined to the first three components. Removal of these components revealed a correlation structure strikingly similar to that observed during wake. These results indicate that, during NREM sleep/anesthesia, the slow oscillation superimposes onto a canonical FC architecture.

Effective Connectivity Measured Using Optogenetically Evoked Hemodynamic Signals Exhibits Topography Distinct from Resting State Functional Connectivity in the Mouse

Brain connectomics has expanded from histological assessment of axonal projection connectivity (APC) to encompass resting state functional connectivity (RS-FC). RS-FC analyses are efficient for whole-brain mapping, but attempts to explain aspects of RS-FC (e.g., interhemispheric RS-FC) based on APC have been only partially successful. Neuroimaging with hemoglobin alone lacks specificity for determining how activity in a population of cells contributes to RS-FC. Wide-field mapping of optogenetically defined connectivity could provide insights into the brain's structure-function relationship. We combined optogenetics with optical intrinsic signal imaging to create an efficient, optogenetic effective connectivity (Opto-EC) mapping assay. We examined EC patterns of excitatory neurons in awake, Thy1-ChR2 transgenic mice. These Thy1-based EC (Thy1-EC) patterns were evaluated against RS-FC over the cortex. Compared to RS-FC, Thy1-EC exhibited increased spatial specificity, reduced interhemispheric connectivity in regions with strong RS-FC, and appreciable connection strength asymmetry. Comparing the topography of Thy1-EC and RS-FC patterns to maps of APC revealed that Thy1-EC more closely resembled APC than did RS-FC. The more general method of Opto-EC mapping with hemoglobin can be determined for 100 sites in single animals in under an hour, and is amenable to other neuroimaging modalities. Opto-EC mapping represents a powerful strategy for examining evolving connectivity-related circuit plasticity.

Designing a large field-of-view two-photon microscope using optical invariant analysis

Conventional two-photon microscopy (TPM) is capable of imaging neural dynamics with subcellular resolution, but it is limited to a field-of-view (FOV) diameter [Formula: see text]. Although there has been recent progress in extending the FOV in TPM, a principled design approach for developing large FOV TPM (LF-TPM) with off-the-shelf components has yet to be established. Therefore, we present a design strategy that depends on analyzing the optical invariant of commercially available objectives, relay lenses, mirror scanners, and emission collection systems in isolation. Components are then selected to maximize the space-bandwidth product of the integrated microscope. In comparison with other LF-TPM systems, our strategy simplifies the sequence of design decisions and is applicable to extending the FOV in any microscope with an optical relay. The microscope we constructed with this design approach can image [Formula: see text] lateral and [Formula: see text] axial resolution over a 7-mm diameter FOV, which is a 100-fold increase in FOV compared with conventional TPM. As a demonstration of the potential that LF-TPM has on understanding the microarchitecture of the mouse brain across interhemispheric regions, we performed in vivo imaging of both the cerebral vasculature and microglia cell bodies over the mouse cortex.

Functional connectivity structure of cortical calcium dynamics in anesthetized and awake mice

The interplay between hemodynamic-based markers of cortical activity (e.g. fMRI and optical intrinsic signal imaging), which are an indirect and relatively slow report of neural activity, and underlying synaptic electrical and metabolic activity through neurovascular coupling is a topic of ongoing research and debate. As application of resting state functional connectivity measures is extended further into topics such as brain development, aging and disease, the importance of understanding the fundamental physiological basis for functional connectivity will grow. Here we extend functional connectivity analysis from hemodynamic- to calcium-based imaging. Transgenic mice (n = 7) expressing a fluorescent calcium indicator (GCaMP6) driven by the Thy1 promoter in glutamatergic neurons were imaged transcranially in both anesthetized (using ketamine/xylazine) and awake states. Sequential LED illumination (λ = 454, 523, 595, 640nm) enabled concurrent imaging of both GCaMP6 fluorescence emission (corrected for hemoglobin absorption) and hemodynamics. Functional connectivity network maps were constructed for infraslow (0.009–0.08Hz), intermediate (0.08–0.4Hz), and high (0.4–4.0Hz) frequency bands. At infraslow and intermediate frequencies, commonly used in BOLD fMRI and fcOIS studies of functional connectivity and implicated in neurovascular coupling mechanisms, GCaMP6 and HbO₂ functional connectivity structures were in high agreement, both qualitatively and also quantitatively through a measure of spatial similarity. The spontaneous dynamics of both contrasts had the highest correlation when the GCaMP6 signal was delayed with a ~0.6–1.5s temporal offset. Within the higher-frequency delta band, sensitive to slow wave sleep oscillations in non-REM sleep and anesthesia, we evaluate the speed with which the connectivity analysis stabilized and found that the functional connectivity maps captured putative network structure within time window lengths as short as 30 seconds. Homotopic GCaMP6 functional connectivity maps at 0.4–4.0Hz in the anesthetized states show a striking correlated and anti-correlated structure along the anterior to posterior axis. This structure is potentially explained in part by observed propagation of delta-band activity from frontal somatomotor regions to visuoparietal areas. During awake imaging, this spatio-temporal quality is altered, and a more complex and detailed functional connectivity structure is observed. The combined calcium/hemoglobin imaging technique described here will enable the dissociation of changes in ionic and hemodynamic functional structure and neurovascular coupling and provide a framework for subsequent studies of neurological disease such as stroke.

Cerebral functional connectivity and Mayer waves in mice: Phenomena and separability

Resting-state functional connectivity is a growing neuroimaging approach that analyses the spatiotemporal structure of spontaneous brain activity, often using low-frequency (<0.08 Hz) hemodynamics. In addition to these fluctuations, there are two other low-frequency hemodynamic oscillations in a nearby spectral region (0.1-0.4 Hz) that have been reported in the brain: vasomotion and Mayer waves. Despite how close in frequency these phenomena exist, there is little research on how vasomotion and Mayer waves are related to or affect resting-state functional connectivity. In this study, we analyze spontaneous hemodynamic fluctuations over the mouse cortex using optical intrinsic signal imaging. We found spontaneous occurrence of oscillatory hemodynamics ∼0.2 Hz consistent with the properties of Mayer waves reported in the literature. Across a group of mice (n = 19), there was a large variability in the magnitude of Mayer waves. However, regardless of the magnitude of Mayer waves, functional connectivity patterns could be recovered from hemodynamic signals when filtered to the lower frequency band, 0.01-0.08 Hz. Our results demonstrate that both Mayer waves and resting-state functional connectivity patterns can co-exist simultaneously, and that they can be separated by applying bandpass filters.

Mapping functional connectivity using cerebral blood flow in the mouse brain

Brain function can be assessed from resting-state functional connectivity (rs-fc) maps, most commonly created by analyzing the dynamics of cerebral hemoglobin concentration. Here, we develop the use of Laser Speckle Contrast Imaging (LSCI) for mapping rs-fc using cerebral blood flow (CBF) dynamics. Because LSCI is intrinsically noisy, we used spatial and temporal averaging to sufficiently raise the signal-to-noise ratio for observing robust functional networks. Although CBF-based rs-fc maps in healthy mice are qualitatively similar to simultaneously-acquired [HbO2]-based maps, some quantitative regional differences were observed. These combined flow/concentration maps might help clarify mechanisms involved in network disruption during disease.

Characterization of a weakly expressed KIR2DL1 variant reveals a novel upstream promoter that controls KIR expression

Members of the human KIR class I MHC receptor gene family contain multiple promoters that determine the variegated expression of KIR on NK cells. In order to identify novel genetic alterations associated with decreased KIR expression, a group of donors was characterized for KIR gene content, transcripts, and protein expression. An individual with a single copy of the KIR2DL1 gene but a very low level of gene expression was identified. The low expression phenotype was associated with a SNP that created a binding site for the inhibitory ZEB1 transcription factor adjacent to a c-Myc binding site previously implicated in distal promoter activity. Individuals possessing this SNP had a substantial decrease in distal KIR2DL1 transcripts initiating from a novel intermediate promoter located 230 bp upstream of the proximal promoter start site. Surprisingly, there was no decrease in transcription from the KIR2DL1 proximal promoter. Reduced intermediate promoter activity revealed the existence of alternatively spliced KIR2DL1 transcripts containing premature termination codons that initiated from the proximal KIR2DL1 promoter. Altogether, these results indicate that distal transcripts are necessary for KIR2DL1 protein expression and are required for proper processing of sense transcripts from the bidirectional proximal promoter.

Optical imaging of disrupted functional connectivity following ischemic stroke in mice

Recent human neuroimaging studies indicate that spontaneous fluctuations in neural activity, as measured by functional connectivity magnetic resonance imaging (fcMRI), are significantly affected following stroke. Disrupted functional connectivity is associated with behavioral deficits and has been linked to long-term recovery potential. FcMRI studies of stroke in rats have generally produced similar findings, although subacute cortical reorganization following focal ischemia appears to be more rapid than in humans. Similar studies in mice have not been published, most likely because fMRI in the small mouse brain is technically challenging. Extending functional connectivity methods to mouse models of stroke could provide a valuable tool for understanding the link between molecular mechanisms of stroke repair and human fcMRI findings at the system level. We applied functional connectivity optical intrinsic signal imaging (fcOIS) to mice before and 72 h after transient middle cerebral artery occlusion (tMCAO) to examine how graded ischemic injury affects the relationship between functional connectivity and infarct volume, stimulus-induced response, and behavior. Regional changes in functional connectivity within the MCA territory were largely proportional to infarct volume. However, subcortical damage affected functional connectivity in the somatosensory cortex as much as larger infarcts of cortex and subcortex. The extent of injury correlated with cortical activations following electrical stimulation of the affected forelimb and with functional connectivity in the somatosensory cortex. Regional homotopic functional connectivity in motor cortex correlated with behavioral deficits measured using an adhesive patch removal test. Spontaneous hemodynamic activity within the infarct exhibited altered temporal and spectral features in comparison to intact tissue; failing to account for these regional differences significantly affected apparent post-stroke functional connectivity measures. Thus, several results were strongly dependent on how the resting-state data were processed. Specifically, global signal regression alone resulted in apparently distorted functional connectivity measures in the intact hemisphere. These distortions were corrected by regressing out multiple sources of variance, as performed in human fcMRI. We conclude that fcOIS provides a sensitive imaging modality in the murine stroke model; however, it is necessary to properly account for altered hemodynamics in injured brain to obtain accurate measures of functional connectivity.

Identification of a KIR antisense lncRNA expressed by progenitor cells

Human NK cells express cell surface class I MHC receptors (KIR) in a probabilistic manner. Previous studies have shown that a distal promoter acts in conjunction with a proximal bidirectional promoter to control the selective activation of KIR genes. We report here the presence of an intron 2 promoter in several KIR genes that produces a spliced antisense transcript. This lncRNA transcript contains antisense sequence complementary to KIR-coding exons 1 and 2 as well as the proximal promoter region of the KIR genes. The antisense promoter contains MZF-1 binding sites, a transcription factor found in hematopoietic progenitors and myeloid precursors. The KIR antisense lncRNA was only detected in progenitor cells or pluripotent cell lines, suggesting a function that is specific for stem cells. Overexpression of MZF-1 in developing NK cells led to decreased KIR expression, consistent with a role for the KIR antisense lncRNA in silencing KIR gene expression early in development.

Identification of bidirectional promoters in the human KIR genes

Although the class I MHC receptors expressed by human and mouse natural killer (NK) cells have distinct molecular origins, they are functional analogues that are expressed in a variegated pattern. The murine Ly49 class I receptors contain bidirectional promoters that have been proposed to control the probabilistic expression of these genes. Whether similar elements are present in the human killer Ig-like receptor (KIR) genes is a fundamental question. A detailed analysis of the 2 kb intergenic region separating the KIR2DL4 gene and the adjacent KIR3DL1 gene revealed that additional promoter elements exist in the human KIR genes. Remarkably, the previously characterized KIR3DL1 proximal promoter possesses bidirectional promoter activity that maps to an 88 bp DNA fragment containing CREB, AML, Sp1 and Ets transcription factor binding sites. Individual KIR genes and alleles possess bidirectional promoters with distinct properties. Analysis of KIR(+)and KIR(-) NK cells and NK precursors indicates that reverse transcripts from the bidirectional promoter are found in cells that lack KIR protein expression, but are not present in mature KIR-expressing NK cells, suggesting that reverse transcription from the proximal promoter blocks gene activation in immature NK and precursor cells.

Identification of distal KIR promoters and transcripts

A more complete understanding of the transcriptional control of the human and murine class I MHC receptors will help to shed light on the mechanism of selective, stochastic, gene activation that operates in these gene families. Studies of the murine Ly49 class I MHC receptor genes have revealed an important role for distal transcripts originating upstream of the proximal promoter. To date, there have been no reports of distal promoters within the functionally analogous human KIR family of class I MHC receptors. In the current study, reverse transcriptase-polymerase chain reaction (RT-PCR) and RNase protection assays were used to reveal the presence of distal KIR transcripts initiating upstream of the previously characterized proximal KIR promoter. The intergenic promoter elements detected were associated with repetitive elements of the Alu and L1 families. Unlike the proximal KIR promoter, the distal promoter regions were not NK cell-specific. KIR genes expressed in a variegated manner produced a low level of distal transcripts containing a large 5' untranslated region. In contrast, the highly expressed KIR2DL4 gene possessed a higher level of spliced distal transcripts that were capable of producing KIR2DL4 protein. The identification of distal KIR promoter elements suggests that intergenic transcripts may influence the expression of KIR genes.

Persistent pollutants urban rivers sediment survey: implications for pollution control

The impacts of diffuse urban sources of pollution on watercourses are quantified. A survey of nine urban streams in Scotland for persistent pollutants in stream sediments is described, together with sediments from SUDS ponds. Determinands reported are: PAHs, total hydrocarbons, and toxic metals (As, Zn, Ni, Pb, Cu, Cr, Cd). Results highlight hydrocarbons as a major urban pollutant, and show significant sediment contamination by toxic metals. The metals that occurred in the highest concentrations varied across the nine streams, but Pb, Cr, Ni, Zn and Cu most frequently present exceeded sediment quality standards. The pattern of contamination by PAHs suggested that pyrolytic sources were more ubiquitous and present in greater quantities than oil spill sources in these urban catchments. Exceptions were the sites below industrial estates. The findings indicate that four levels of activity will be needed to control urban diffuse sources of pollution: reductions in quantities of toxic pollutants used by manufacturers in the motor and construction industries; housekeeping measures to minimise storage and handling risks for oil and chemicals; public engagement to minimise polluting activities such as dumping oil and chemicals, and private car use; use of SUDS technology, including retro-fits in the worst affected urban areas.

Multidimensional assessment of anger in Vietnam veterans with posttraumatic stress disorder

This study examined the effects of combat exposure and posttraumatic stress disorder (PTSD) on dimensions of anger in Vietnam veterans. Vietnam combat veterans were compared with Vietnam era veterans without war zone duty on the Multidimensional Anger Inventory (MAI). Combat veterans were not significantly more angry than their veteran peers who did not serve in Southeast Asia. Additionally, various parameters of war zone duty were not highly associated with anger scores. However, combat veterans with PTSD scored significantly higher than veterans without PTSD on measures of anger arousal, range of anger-eliciting situations, hostile attitudinal outlook, and tendency to hold anger in. These results suggest that PTSD, rather than war zone duty, is associated with various dimensions of angry affect.

Structure, properties, and tissue localization of apoplastic alpha-glucosidase in crucifers

Apoplastic alpha-glucosidases occur widely in plants but their function is unknown because appropriate substrates in the apoplast have not been identified. Arabidopsis contains at least three alpha-glucosidase genes; Aglu-1 and Aglu-3 are sequenced and Aglu-2 is known from six expressed sequence tags. Antibodies raised to a portion of Aglu-1 expressed in Escherichia coli recognize two proteins of 96 and 81 kD, respectively, in vegetative tissues of Arabidopsis, broccoli (Brassica oleracea L.), and mustard (Brassica napus L.). The acidic alpha-glucosidase activity from broccoli flower buds was purified using concanavalin A and ion-exchange chromatography. Two active fractions were resolved and both contained a 96-kD immunoreactive polypeptide. The N-terminal sequence from the 96-kD broccoli alpha-glucosidase indicated that it corresponds to the Arabidopsis Aglu-2 gene and that approximately 15 kD of the predicted N terminus was cleaved. The 81-kD protein was more abundant than the 96-kD protein, but it was not active with 4-methylumbelliferyl-alpha-D-glucopyranoside as the substrate and it did not bind to concanavalin A. In situ activity staining using 5-bromo-4-chloro-3-indolyl-alpha-D-glucopyranoside revealed that the acidic alpha-glucosidase activity is predominantly located in the outer cortex of broccoli stems and in vascular tissue, especially in leaf traces.

Inhibition of Fas (CD95) expression and Fas-mediated apoptosis by oncogenic Ras

The ras oncogene plays an important role in the multistep progression to cancer by activation of signal transduction pathways that contribute to aberrant growth regulation. Although many of these effects are cell autonomous, the ras oncogene also regulates the expression of genes that alter host/tumor interactions. We now extend the mechanisms through which ras promotes tumor survival by demonstrating that oncogenic Ras inhibits expression of the fas gene and renders Ras-transformed cells resistant to Fas-induced apoptosis. A panel of Ras-transformed clones exhibited a marked inhibition in fas mRNA and Fas cell surface expression as compared with untransformed parental cell lines. Fas expression was induced by culture in the presence of IFN-gamma + tumor necrosis factor alpha; however, the maximal level attained in Ras transformants was approximately 10-fold below the level of untransformed cells. Whereas untransformed cells were sensitive to apoptotic death induced by cross-linking surface Fas (especially after cytokine treatment), Ras-transformed cells were very resistant to Fas-induced death even under the most stringent assay conditions. To demonstrate that this resistance was mediated by oncogenic Ras and not secondary genetic events, pools of Ras-transformed cells were generated using a highly efficient retroviral transduction technique. Transformed pools were assayed 6 days after infection and demonstrated a marked decrease in fas gene expression and Fas-mediated apoptosis. Oncogenic Ras did not promote general resistance to apoptosis, because ectopic expression of a fas cDNA in Ras-transformed cells restored sensitivity to Fas-induced apoptosis. These data indicate that oncogenic Ras inhibits basal levels of expression of the fas gene, and although cytokine signal transduction pathways are functional in these cells, the level of surface Fas expression remains below the threshold required for induction of apoptosis. These data identify a mechanism by which Ras-transformed cells may escape from host-mediated immune destruction.

T cell- and NK cell-independent inhibition of hepatic metastases by systemic administration of an IL-12-expressing recombinant adenovirus

IL-12 is a potent immunoregulatory cytokine that has been shown to mediate tumor regression in a variety of tumor models. We describe the construction of AdCMV-IL-12, a recombinant adenovirus that encodes both subunits of IL-12 under transcriptional control of the CMV promoter. This recombinant virus efficiently infects a wide variety of cell types leading to the production of high levels of biologically active IL-12. Because the liver is a primary site of infection after i.v.-administered adenovirus, we tested the therapeutic efficacy of this virus in a murine hepatic metastasis tumor model. Systemic administration of AdCMV-IL-12 dramatically inhibited the formation of 3-day Renca hepatic metastases (mean of 16 metastases per liver) compared with the control virus AdCMV-betagal (mean of 209) or vehicle alone (mean of 272). Histologic analysis indicated that metastatic growth inhibition was accompanied by a dramatic perivascular infiltrate consisting of T cells, macrophages, and neutrophils. Therapeutic efficacy was not diminished in animals depleted of CD4+ or CD8+ T cells, or in SCID mice, even after NK cell ablation. In the latter case, a hepatic perivascular infiltrate composed of macrophages and neutrophils was observed after AdCMV-IL-12-treatment, while numerous activated Kupffer cells were noted in the hepatic parenchyma. Analysis of therapy-induced changes in hepatic gene expression demonstrated increased levels of IP-10 and Mig RNAs, but no increase in iNOS, Fas, or FasL RNA levels was observed. Our data suggest a model of metastatic growth inhibition mediated by nonlymphocyte effector cells including macrophages and neutrophils and that may involve anti-angiogenic chemokines.

Sensitivity of fluorochrome microscopy for detection of Mycobacterium tuberculosis versus nontuberculous mycobacteria

The results for 6,532 consecutive mycobacterial respiratory specimens collected from 1,040 patients from 1993 to 1995 in a Texas hospital were studied to determine the sensitivity of fluorescence microscopy for detection of Mycobacterium tuberculosis and nontuberculous mycobacteria (NTM). Smears were positive for acid-fast bacilli (AFB) in 63% (677 of 1,082) of specimens growing M. tuberculosis and 56% (638 of 1,148) of specimens growing the four most common species of NTM. Smear positivity by species was 58% (446 of 776) for M. avium complex, 51% (154 of 300) for rapidly growing mycobacteria (98% were M. abscessus), 78% (29 of 37) for M. kansasii, and 26% (9 of 35) for M. gordonae. Definite or probable disease by clinical criteria was present in 79% of patients with M. avium complex, 93% of patients with rapidly growing mycobacteria, 100% of patients with M. kansasii, and 0% of patients with M. gordonae. Patients with M. avium complex had a low incidence of AIDS (7%), and approximately 50% of non-AIDS patients had upper-lobe cavitary disease and 50% had nodular bronchiectasis. Only 23 of 6,532 (0.35%) of AFB smears were positive with a negative culture excluding patients on therapy for established mycobacterial disease. These studies suggest that NTM are as likely as M. tuberculosis to be detected by fluorescent microscopy in specimens from patients from areas endemic for NTM lung disease and at low risk for AIDS.

Should balloon angioplasty and stents have any role in operative intervention for lower extremity ischemia?

Balloon angioplasty has been combined with open vascular surgery to treat lower extremity ischemia due to multilevel occlusive disease. The purposes of this study were: (1) to compare staged and simultaneous approaches to determine the optimal method for combining endovascular and open techniques and; (2) to assess the role of stents in intraoperative balloon angioplasty. Among 274 patients undergoing lower extremity revascularization over 30 months, 38 (13.9%) required a combination of endovascular and open techniques; 17 were staged (endovascular followed at an interval by distal open surgery) and 21 were simultaneous (intraoperative balloon angioplasty with or without stent placement at the time of open surgery). Groups were similar with respect to demographics, lesions treated with endovascular intervention, incidence and location of stent placement, and results of surgery. Additional operating time required for intraoperative endovascular intervention was 41.0 +/- 30.7 min., fluoroscopic time was 3.9 +/- 2.4 min. and contrast administered was 58.8 +/- 28.1 ml. There was no perioperative mortality. Length of stay was longer in the staged than in the simultaneous group (p < 0.01). Cumulative combined primary patency at 1 year by life-table methods was 82 +/- 10% in the staged group and 83 +/- 9% in the simultaneous group (p = 0.79). Mean follow-up was 13 +/- 6 months. There is a role for balloon angioplasty and stent placement in operative revascularization of ischemic limbs in selected patients: patency was similar to that produced with the staged approach while the length of stay was shorter. Intraoperative balloon angioplasty is safe and effective and stents permit a measure of control in assuring an optimal intraoperative postangioplasty result.

Selection of skin test antigens to evaluate PPD anergy

BACKGROUND

A purified protein derivative (PPD) tuberculin skin test may be nonreactive because of cutaneous anergy, technical problems with the test, or absence of tuberculosis infection. This study investigated the sensitivity and specificity of five test agents in measuring cutaneous anergy when the PPD test is nonreactive. Agents evaluated include antigens for Candida, mumps, histoplasmin, tetanus, and Trichophyton.

METHODS

Delayed-type hypersensitivity skin test records were analyzed in 1113 patients admitted to the University of Texas Health Center at Tyler from December 1988 through June 1993. These patients were admitted with initial diagnoses of diseases other than active tuberculosis or human immunodeficiency virus infection.

RESULTS

Patients with a negative PPD test reacted most often to the control skin test Candida (63.5%), followed by mumps (52.2%), histoplasmosis (37.2%), tetanus (35.7%), and Trichophyton (6.1%). Analysis of these data indicates that the use of more than three of the four most commonly reactive control tests (Candida, mumps, and histoplasmin or tetanus) yielded minimal additional precision in the determination of skin test anergy compared with using all five control skin tests. This finding remained constant whether the PPD was considered negative at < 5 mm, < 10 mm, or < 15 mm of induration.

CONCLUSIONS

In controlling for false-negative PPD tests, the use of three skin test antigens, Candida, mumps, and tetanus, should provide reliable control for delayed-type hypersensitivity anergy.

A case of recurrent typhoid fever in the United States: importance of the grandmother connection and the use of large restriction fragment pattern analysis of genomic DNA for strain comparison

An 8-year old girl was infected for a second time with Salmonella typhi by contact with her grandmother, a known typhoid carrier. The S. typhi from both patient and grandmother had closely related genomic pulsed field gel electrophoresis patterns that differed from epidemiologically unrelated strains. The girl responded well to a 14-day course of oral trimethoprimsulfamethoxazole. The grandmother was treated successfully with a 28-day regimen of oral ciprofloxacin. Typhoid fever remains an endemic disease in the United States, largely because of recognized chronic stool carriers. Most of these carriers had typhoid in the preantibiotic era and remain potential sources of disease when they provide meals for others, not uncommonly grandchildren. The importance of this "grandmother" connection to endemic typhoid fever is reviewed, as is the potential use of pulsed field gel electrophoresis pattern analysis for comparison of strains of S. typhi.

Glial cells of the oligodendrocyte lineage express both kainate- and AMPA-preferring subtypes of glutamate receptor

mRNAs for AMPA- and kainate-preferring glutamate receptor subunits are expressed abundantly in the CNS, yet functional studies of neurons and glia from brain suggest selective expression of AMPA receptors. We now show that glial cells of the O-2A lineage express rapidly desensitizing responses to kainate, mRNAs for GluR6, GluR7, KA-1, and KA-2, rapidly desensitizing responses to AMPA, and mRNAs for GluR-B, -C, and -D. Analysis of glutamate receptor currents in single cells reveals two receptor populations with high and low affinity for kainate and different sensitivity for potentiation by concanavalin A and for block of desensitization by cyclothiazide. Our experiments describe the characterization of native kainate-preferring receptors in glia and reveal coexpression in single cells of functional AMPA- and kainate-preferring receptors.

Initial clinical assessment of the comatose patient: cerebral malaria vs. meningitis

One hundred twenty-one Liberian children were admitted in coma to the ELWA Hospital, Monrovia, Liberia. Admitting diagnoses, before lumbar puncture, were compared with discharge diagnoses. Ninety-four children were discharged with a final diagnosis of cerebral malaria and 27 with a diagnosis of meningitis. The admitting diagnosis was correct in 76.6% (72 of 94) of patients with cerebral malaria and 59.3% (16 of 27) of patients with meningitis. The cerebrospinal fluid leukocyte count was the single most significant factor in determining the correct diagnosis. Without the cerebrospinal fluid analysis, the discriminant accuracy (77%), i.e. definitive separation of the two illnesses, was comparable to the physician's admission diagnosis (73%). Other data contributing to the differential diagnosis of cerebral malaria and meningitis included the number of days of fever before admission, the presence or absence of nuchal rigidity, fontanelle fullness and peripheral blood malaria smear. Mortality rates for cerebral malaria and meningitis were 14.9 and 29.6%, respectively. These data suggest that physicians cannot reliably discriminate between cerebral malaria and meningitis without cerebrospinal fluid analysis.

Photothrombotic lesions of the frontal cortex impair the performance of the delayed non-matching to position task by rats

The effects of photochemically induced lesions of the frontal cortex on the short-term memory capacity of the rat have been investigated using the delayed non-matching to position task. Pretrained animals received lesions and were tested 4 days after surgery and twice per week for 3 weeks. The lesions produced a profound impairment of performance of this task which was still evident 3 weeks after surgery. Spontaneous locomotor activity was recorded 7 days after surgery and no difference was found between the control and lesion group. These effects indicated a generalized disruption of performance of this task in the absence of motor dysfunction. These results suggest that photothrombotic lesions of the frontal cortex can produce reliable, long-term behavioural deficits.

Effect of cyclooxygenase inhibition on amphotericin B-induced lung injury in awake sheep

Amphotericin therapy in humans has been reported to cause severe pulmonary dysfunction in some patients, and these abnormalities have been reproduced in unanesthetized sheep. To determine the role of cyclooxygenase products in this response, paired, random-order experiments in 11 sheep were done using the cyclooxygenase inhibitor ibuprofen. Ibuprofen blunted increases in pulmonary artery pressure (Ppa) after amphotericin (peak Ppa 38 +/- 3 cm H2O in amphotericin-alone group vs. 30 +/- 1 cm H2O in ibuprofen + amphotericin group, P less than .05) and reduced peak lung lymph flow to approximately 170% of baseline compared with 350% of baseline in amphotericin-alone group (P less than .05). In addition, the increase in airflow resistance across the lung and the decrease in partial pressure of oxygen seen after amphotericin was blocked by ibuprofen. Therefore, amphotericin-induced lung dysfunction is produced in part through the generation of cyclooxygenase products of arachidonic acid metabolism and can be ameliorated by pretreatment with the cyclooxygenase inhibitor ibuprofen.

Acute hemorrhagic conjunctivitis

Acute hemorrhagic conjunctivitis, an infection caused by enterovirus 70 and a variant of coxsackievirus A24, is characterized by the rapid onset of severely painful conjunctivitis and subconjunctival hemorrhage. The condition is usually benign and resolves in five to seven days; however, a polio-like paralysis (radiculomyelitis) develops in approximately one in 10,000 patients infected with enterovirus 70. No treatment is available. Information about acute hemorrhagic conjunctivitis should be provided to patients and the community in order to prevent undue alarm, discourage home remedies and control the spread of this highly contagious disease.

A descriptive study of 42 cases of Branhamella catarrhalis pneumonia

PURPOSE

We studied the clinical and laboratory findings of patients with pneumonia due to Moraxella (Branhamella) catarrhalis to better characterize the types of patients who develop this pneumonia, the clinical features of the illness, and the type of and response to drug therapy, as well as the immediate and long-term survival of these patients.

PATIENTS AND METHODS

Patients with sputum samples that met cellular criteria as quality samples and that grew B. catarrhalis as the sole pathogen were identified retrospectively from microbiology records at a regional referral hospital for cardiac and pulmonary diseases. Records of these patients were reviewed to identify patients with radiographic findings of pneumonia. Clinical and laboratory characteristics of these patients were then studied in detail.

RESULTS

Forty-two patients who met the criteria for B. catarrhalis pneumonia were identified. Most patients were elderly (over 65 years; 55 percent), malnourished (69 percent), and had severe chronic obstructive pulmonary disease or another serious underlying disease (98 percent). The seasonal incidence of this pneumonia was October through April (88 percent), with the annual number of cases having increased since 1982. The clinical presentation was typically mild. Interstitial or mixed interstitial-alveolar infiltrates superimposed on pre-existing chronic lung disease was the most common radiographic finding. Approximately 90 percent of sputa were acceptable for Gram stain and contained 10 to more than 50 gram-negative cocci/1,000 x field. All cultures produced a heavy growth of B. catarrhalis, with 67 percent of strains positive for beta-lactamase. No patient had identified bacteremia (zero of 25 tested). Therapy with numerous agents including cefotaxime, amoxicillin/clavulanic acid, and trimethoprim/sulfamethoxazole resulted in a good clinical and bacteriologic response. However, 45 percent of patients died of their underlying diseases on this admission or within three months.

CONCLUSION

These findings provide a good profile of B. catarrhalis pneumonia. Despite the mild character of the illness, the pneumonia occurs in patients with end-stage pulmonary or malignant disease and almost 50 percent of patients die of their underlying diseases within three months.

The effects of adenosine triphosphate and related purines on arterial resistance vessels in vitro and in vivo

The distribution of P2-purinoceptors in pre-capillary resistance vessels was studied in vitro, using Krebs perfused rabbit ears and in vivo, in autoperfused hindquarters, intestinal and renal vasculatures of pentobarbitone anaesthetised cats. ATP (10(-10)-10(-6) mol i.a.) caused dose-dependent vasodilatation which, in the rabbit ear, was antagonised by reactive blue 2 (10(-5)-10(-4) M). At the highest concentration of reactive blue 2, ATP responses were reversed and a dose-dependent vasoconstriction was seen. Reactive blue 2, also reduced the vasodilator responses to carbachol and to a lesser extent papaverine which suggests that the antagonist has limited selectivity. The rank order of potency of ATP analogues as vasodilators, 2-methylthio ATP greater than ADP greater than ATP greater than alpha,beta-methylene and beta,gamma-methylene ATP, suggests P2y purinoceptors are involved. The selective P2x-purinoceptor agonist, alpha,beta-methylene ATP, caused pronounced vasoconstriction in the rabbit ear and cat intestinal vasculature which was not antagonised by phenoxybenzamine. In contrast, alpha,beta-methylene ATP had little effect in the autoperfused hindquarters and renal vasculatures suggesting a very heterogeneous distribution of P2x-purinoceptors in the cat. The results are consistent with the proposal that two distinct types of P2-purinoceptors are present on blood vessels.

Branhamella catarrhalis infections

Branhamella (Moraxella) catarrhalis is responsible for a significant number of bronchopulmonary infections in adults, as well as otitis media and sinusitis in children. This gram-negative diplococcus is indistinguishable from Neisseria gonorrhoeae on gram-stained smear. Many strains of the organism produce beta-lactamase and are resistant to the penicillins and other beta-lactam antibiotics. When B. catarrhalis is the probable pathogen, a beta-lactamase-resistant antibiotic is the initial drug of choice in both adults and children.

Brucellosis

Brucellosis is common worldwide in a variety of animals and is markedly underreported in man. Brucella abortus seems to be decreasing in cattle herds, but new animal reservoirs are being discovered. Human infection presents a difficult diagnostic challenge because of its protean manifestations and multiplicity of organ involvement. Symptoms vary, but fever, chills, weakness and weight loss are common. Several antibiotics are effective.

Uniform chromatographic conditions for quantifying urinary catecholamines, metanephrines, vanillylmandelic acid, 5-hydroxyindoleacetic acid, by liquid chromatography, with electrochemical detection

Uniform liquid-chromatographic conditions were developed such that we could quantify norepinephrine, epinephrine, normetanephrine, metanephrine, vanillylmandelic acid, and 5-hydroxyindoleacetic acid in urine by using a single mobile phase of monochloroacetic acid and citric acid, 0.1 mol/L each. All compounds were separated on a C18 column and detected electrochemically at a potential of +0.800 V. Optimization of these uniform chromatographic conditions significantly shortens the changeover time required from one assay to another, resulting in a substantial savings of time and cost to the laboratory.

Uniform chromatographic conditions for quantifying urinary catecholamines, metanephrines, vanillylmandelic acid, 5-hydroxyindoleacetic acid, by liquid chromatography, with electrochemical detection

Uniform liquid-chromatographic conditions were developed such that we could quantify norepinephrine, epinephrine, normetanephrine, metanephrine, vanillylmandelic acid, and 5-hydroxyindoleacetic acid in urine by using a single mobile phase of monochloroacetic acid and citric acid, 0.1 mol/L each. All compounds were separated on a C18 column and detected electrochemically at a potential of +0.800 V. Optimization of these uniform chromatographic conditions significantly shortens the changeover time required from one assay to another, resulting in a substantial savings of time and cost to the laboratory.

Participants in prospective, randomized clinical trials for resected non-small cell lung cancer have improved survival compared with nonparticipants in such trials

The survival of 78 patients with resected non-small cell lung cancer entered in prospective, randomized investigational trials is compared to that of a population-based group of control patients not included in such trials. The survival of trial patients is significantly better than that of controls (P less than 0.001). This survival advantage for trial participants is most apparent among late Stage I patients, and is observed after matching for known prognostic factors (i.e., primary tumor size, nodal status, tumor histology) and after adjusting in the analysis for age, sex, and the administration of radiation therapy. Several explanations for the improved outcome for trial patients are explored, including differences in preoperative evaluation, staging, surgical technique, placebo effects, and patient motivation. These results suggest the possibility that inclusion in these controlled cancer trials may have had an inherent advantage for all participants.

Enchondroma protuberans of the rib

Enchondroma protuberans of the rib may be indistinguishable from osteochondroma or chondrosarcoma. The problems of needle biopsy and the confusion which arose in the preoperative and intraoperative evaluation of two previous cases from the literature were avoided in the present case by total resection of the lesion. Where possible, total resection is recommended for accurate diagnosis.

Long-term survival in small-cell carcinoma of the lung: a population experience

Small-cell lung carcinoma (SCLC) is a rapidly progressive and fatal disease. Historically, surgical resection or radiotherapy of the primary tumor has done little to prolong survival, although the use of combination chemotherapy is more effective. Reported here is the survival experience of 1,538 incident cases of SCLC identified through the Surveillance, Epidemiology and End Results Program in western Washington State from 1974 to 1982. The survival experience of this population series is similar to that reported from specialized referral centers. For 71 of 78 persons surviving at least 24 months, the original diagnostic slides were independently reviewed, 47 cases being confirmed as SCLC. No differences were found in actuarial survival estimates between those confirmed and those not confirmed as SCLC. Multivariate survival analysis was conducted to estimate the effects on survival of stage, therapy, age, sex, primary site, and histologic type. All factors except primary site and histologic type significantly influence initial survival rates. However, the only factor related to post--two-year (ie, long-term) survival, once stage is accounted for, is whether surgery was received as a first course of therapy. Those not receiving surgery were at four times the risk of death as those who did. These results indicate that long-term survival can be achieved in patients with SCLC treated in the community, and that the chance of surviving an additional two years for such patients is approximately 40%.

Obstruction of the left ventricular outflow tract by the mitral valve due to a muscle band

This paper details a rare cause of subaortic obstruction--a muscle band tethering the anterior leaflet of the mitral valve to the ventricular septum. Excision of this band released the leaflet and cured the obstruction. The patient also had a discrete subaortic membranous obstruction, the membrane being excised.

Imaging of melanoma with L-131-labeled monoclonal antibodies

Mouse monoclonal antibodies and Fab fragments specific for p97, a melanoma-associated antigen, were used to image metastatic human melanoma. Preclinical studies in athymic mice showed antigen-specific uptake in melanoma xenografts, and toxicity tests in rabbits gave no evidence for tissue damage after injection of up to 100 times the amount of antibody used in humans. Six patients received 1 mg labeled antibody, and one patient received 1 mg of labeled Fab. No. toxic side effects were observed. All of the six patients had positive scans, visualizing 22 of 25 (88%) of lesions larger than 1.5 cm. In tumors from two patients, greater uptake of p97-specific, versus control IgG and Fab, respectively, was documented by biopsy. Antibodies to mouse immunoglobulin appeared in three patients receiving 1 mg or more of radiolabeled mouse antibody.

Staged bilateral thoracotomies for multiple pulmonary arteriovenous malformations complicating hereditary hemorrhagic telangiectasia

A patient with hereditary hemorrhagic telangiectasia (Osler-Weber-Rendu syndrome) with multiple bilateral pulmonary arteriovenous malformations was hypoxic, cyanotic, polycythemic, and severely limited by dyspnea on exertion. Following staged bilateral thoracotomies, with removal of 23 major fistulas (12 from the right lung and 11 from the left), marked improvement in symptoms, blood gases, and objective measurements of exercise tolerance occurred.

Immunological studies in a double blind randomized trial comparing intrapleural BCG against placebo in patients with resected stage I non-small cell lung cancer

Immunological data were obtained during the course of a randomized trial comparing intrapleural BCG plus oral isoniazid (INH) with intrapleural saline plus oral placebo after resection of stage I non-small cell lung cancer. Immunological testing with a variety of assays was carried out with good standardization among six collaborating laboratories and with good reproducibility within each laboratory. Those patients with larger tumors tended to have higher initial white cell counts. The percentage of lymphocytes in the differential was greatest in those with non-squamous cancer histology. Otherwise, no associations were found between initial immunologic parameters and baseline variables. The main effect of BCG/INH therapy was to cause statistically significant increases in purified protein derivative (PPD) skin test induration and PPD in vitro blastogenesis compared with controls. Other skin tests and in vitro assays increased more in the saline/placebo control group, but these treatment differences were usually not statistically significant. Initial white count and neutrophil count elevations were found to be associated with increased risk of recurrence. Even after adjustment for treatment and tumor stage, initial neutrophil count elevation was associated with increased risk of recurrence. Surprisingly, a low 29 degrees C T cell rosette index was associated with a decreased risk of recurrence, though the differences were minimal. Serial immunological tests were carried out to evaluate their potential for monitoring disease recurrence. White count elevations continued to be significantly associated with increased risk of recurrence, but more follow-up data are needed before other associations can be assessed.

Immunology of sarcomas

Tumor antigens have now been demonstrated for most experimentally induced tumors by in vivo transplantation techniques, but the demonstration of antigens unique to human tumors has depended on in vitro methods. We have reviewed 1) the evidence that experimental sarcomas express tumor-specific transplantation antigens and that responses against these antigens can be protective in vivo; 2) the in vitro evidence for the existence to antigens associated with sarcomas; and 3) the use of cell hybridization techniques to produce monoclonal antibody to define the distribution of cell surface antigens expressed by human sarcoma cells.

T cell synergy in the rat: serologic characterization of T cell subsets

The W3/25+ T cell subset in rats, defined by a xenogeneic monoclonal antibody and separated by using the FACS, was demonstrated to be the proliferating cell type in the in vitro MLC and to provide an amplifier function for the W3/25- T cell subset in the generation of cytotoxic effector cells to alloantigenic targets.

T cell synergy in the rat: serologic characterization of T cell subsets

The W3/25+ T cell subset in rats, defined by a xenogeneic monoclonal antibody and separated by using the FACS, was demonstrated to be the proliferating cell type in the in vitro MLC and to provide an amplifier function for the W3/25- T cell subset in the generation of cytotoxic effector cells to alloantigenic targets.

Protein antigens of normal and malignant human cells identified by immunoprecipitation with monoclonal antibodies

Spleen cells from a mouse immunized with human melanoma cells were fused with mouse myeloma cells, and somatic cell hybrids were grown in selective medium. Eight hybrids, which secreted antibodies to protein antigens of the melanoma cell line, were identified by immunoprecipitation of a 125I-labeled melanoma cell lysate followed by sodium dodecyl sulfate-gel electrophoresis of the immunoprecipitates and autoradiography. Seven of the eight melanoma proteins identified in this way were present at the cell surface. Two of the cell surface proteins, p80 and p97, were not detected in autologous fibroblasts.

Synergy in proliferative and cytotoxic responses of WF rats to syngeneic Gross virus-induced lymphoma cells in vitro

A synergistic interaction between rat lymphoid cell subsets was found for the in vitro immune response to the syngeneic Gross virus-induced lymphoma (C58NT)D. Mixtures of thymocytes and lymph node cells from inbred WF rats primed in vivo to the lymphoma demonstrated significantly greater proliferative and cytotoxic reactivities in vitro than would be expected from the sum of the reactivities of the two cell types tested separately. A soluble extract of nonimmune syngeneic thymocytes, shown in previous studies to amplify the in vitro responses to alloantigen, was also demonstrated to increase significantly proliferative and cytotoxic responses in vitro to syngeneic lymphoma cells. Preliminary evidence indicated that this soluble thymus amplifier factor differed from previously described thymus factors.

Preliminary results of combined surgery and adjuvant Bacillus Calmette-Guérin plus levamisole treatment of resectable lung cancer

The administration of intrapleural bacillus Calmette-Guérin (BCG) alone and intrapleural BCG plus levamisole was compared to placebo in patients with resectable, non-small cell cancer of the lung. This report is based on an interim analysis of 100 eligible patients with a median followup of 245 days. No significant treatment effects are apparent at the present time, although current trends are consistent with an approximate 30% reduction in recurrence rate in patients receiving intrapleural BCG. There is little evidence to suggest that the addition of levamisole will contribute to this effect. A relationship between purified protein derivative conversion and tumor recurrence is apparent. Failure to manifest purified protein derivative conversion following administration of intrapleural BCG is associated with a significantly greater risk of tumor recurrence.

Amplification of the proliferative response to alloantigen by a factor present in an extract of syngeneic thymic lymphoid cells

A synergistic interaction in the proliferative response to alloantigen has been previously noted when intact thymus cells are cultured with post-thymic (peripheral) lymphoid cells. In the present study, a factor extracted from the thymus has been shown to similarly enhance the reactivity of syngeneic lymph node cells and thus to retain the amplifier activity of intact thymus cells. The factor has no effect on lymphoid cell proliferation in the absence of alloantigen. Cells with amplifier activity are found in highest concentration in the thymus but also may be detected in spleen cells that are nonadherent to nylon wool. The factor is shown in these experiments to be derived from thymic lymphoid cells and to act primarily upon post-thymic (peripheral) lymphoid cells. As such, this factor appears to be distinct from various other thymus factors that have been localized to thymic reticuloepithelial elements and that are thought to effect predominantly the differentiation of T-cell precursors.