Rapid Diagnostic Testing for Response to the Monkeypox Outbreak - Laboratory Response Network, United States, May 17-June 30, 2022

As part of public health preparedness for infectious disease threats, CDC collaborates with other U.S. public health officials to ensure that the Laboratory Response Network (LRN) has diagnostic tools to detect Orthopoxviruses, the genus that includes Variola virus, the causative agent of smallpox. LRN is a network of state and local public health, federal, U.S. Department of Defense (DOD), veterinary, food, and environmental testing laboratories. CDC developed, and the Food and Drug Administration (FDA) granted 510(k) clearance* for the Non-variola Orthopoxvirus Real-time PCR Primer and Probe Set (non-variola Orthopoxvirus [NVO] assay), a polymerase chain reaction (PCR) diagnostic test to detect NVO. On May 17, 2022, CDC was contacted by the Massachusetts Department of Public Health (DPH) regarding a suspected case of monkeypox, a disease caused by the Orthopoxvirus Monkeypox virus. Specimens were collected and tested by the Massachusetts DPH public health laboratory with LRN testing capability using the NVO assay. Nationwide, 68 LRN laboratories had capacity to test approximately 8,000 NVO tests per week during June. During May 17-June 30, LRN laboratories tested 2,009 specimens from suspected monkeypox cases. Among those, 730 (36.3%) specimens from 395 patients were positive for NVO. NVO-positive specimens from 159 persons were confirmed by CDC to be monkeypox; final characterization is pending for 236. Prompt identification of persons with infection allowed rapid response to the outbreak, including isolation and treatment of patients, administration of vaccines, and other public health action. To further facilitate access to testing and increase convenience for providers and patients by using existing provider-laboratory relationships, CDC and LRN are supporting five large commercial laboratories with a national footprint (Aegis Science, LabCorp, Mayo Clinic Laboratories, Quest Diagnostics, and Sonic Healthcare) to establish NVO testing capacity of 10,000 specimens per week per laboratory. On July 6, 2022, the first commercial laboratory began accepting specimens for NVO testing based on clinician orders.

An engineered antibody binds a distinct epitope and is a potent inhibitor of murine and human VISTA

V-domain immunoglobulin (Ig) suppressor of T cell activation (VISTA) is an immune checkpoint that maintains peripheral T cell quiescence and inhibits anti-tumor immune responses. VISTA functions by dampening the interaction between myeloid cells and T cells, orthogonal to PD-1 and other checkpoints of the tumor-T cell signaling axis. Here, we report the use of yeast surface display to engineer an anti-VISTA antibody that binds with high affinity to mouse, human, and cynomolgus monkey VISTA. Our anti-VISTA antibody (SG7) inhibits VISTA function and blocks purported interactions with both PSGL-1 and VSIG3 proteins. SG7 binds a unique epitope on the surface of VISTA, which partially overlaps with other clinically relevant antibodies. As a monotherapy, and to a greater extent as a combination with anti-PD1, SG7 slows tumor growth in multiple syngeneic mouse models. SG7 is a promising clinical candidate that can be tested in fully immunocompetent mouse models and its binding epitope can be used for future campaigns to develop species cross-reactive inhibitors of VISTA.

Complete Reconstitution and Deorphanization of the 3 MDa Nocardiosis-Associated Polyketide Synthase

Several Nocardia strains associated with nocardiosis, a potentially life-threatening disease, house a nonamodular assembly line polyketide synthase (PKS) that presumably synthesizes an unknown polyketide. Here, we report the discovery and structure elucidation of the NOCAP (nocardiosis-associated polyketide) aglycone by first fully reconstituting the NOCAP synthase in vitro from purified protein components followed by heterologous expression in E. coli and spectroscopic analysis of the purified products. The NOCAP aglycone has an unprecedented structure comprised of a substituted resorcylaldehyde headgroup linked to a 15-carbon tail that harbors two conjugated all-trans trienes separated by a stereogenic hydroxyl group. This report is the first example of reconstituting a trans-acyltransferase assembly line PKS in vitro and of using these approaches to "deorphanize" a complete assembly line PKS identified via genomic sequencing. With the NOCAP aglycone in hand, the stage is set for understanding how this PKS and associated tailoring enzymes confer an advantage to their native hosts during human Nocardia infections.

Division of Attention: The Single-Channel Hypothesis Revisited

Two experiments are reported in which subjects performed two forced-paced serial reaction time tasks separately and together at their maximum sustainable rates of information processing. Experiment 1 investigated the effects on the relationship between single- and dual-task performance of using tasks with the same or different input and output modality characteristics; an additional condition tested the effects on this relationship of using tasks with higher S–R compatibility. Experiment 2 investigated the effects on the relationship between single- and dual-task performance of varying information load (number of S–R alternatives). No significant differences were found in subjects’ capacities to process information in single- and dual-task conditions. This finding was unaffected by: (a) the absolute information levels of the tasks, (b) whether inputs and/or outputs involved the same or different modalities, or (c) the level of S–R compatibility. The data from both experiments provide strong support for the single-channel hypothesis.

The M694V mutation in Armenian-Americans: a 10-year retrospective study of MEFV mutation testing for familial Mediterranean fever at UCLA

Familial Mediterranean fever (FMF), inherited in an autosomal recessive manner, is a systemic auto-inflammatory disorder characterized by recurrent attacks of fever with peritonitis, pleuritis, synovitis and erysipeloid rash. The marenostrin-encoding fever (MEFV) gene, located on chromosome 16p13.3, is the only gene in which mutations are currently known to cause FMF. To correlate specific genotypes with adverse phenotypes of affected populations residing in the Western United States, a retrospective case series review was conducted of all MEFV gene mutation testing completed at UCLA Clinical Molecular Diagnostic Laboratory between February 2002 and February 2012, followed by clinical chart review of all subjects who either have a single or double mutation. All 12 common mutations in the MEFV gene were analyzed and the M694V variant was found to be associated with an adverse FMF clinical outcome in the Armenian-American population, manifested by earlier onset of disease, increased severity of disease, and renal amyloidosis.

Transmittance ratio constrained retrieval technique for lidar cirrus measurements

This letter describes a lidar retrieval technique that uses the transmittance ratio as a constraint to determine an average lidar ratio as well as extinction and backscatter coefficients of transparent cirrus clouds. The cloud transmittance ratio is directly obtained from two adjacent elastic lidar backscatter signals. The technique can be applied to cirrus measurements where neither the molecular scattering dominant signals above and below the cloud layer are found nor cloudfree reference profiles are available. The technique has been tested with simulated lidar signals and applied to backscatter lidar measurements at Hampton University, Hampton, Virginia.

The anticholinergic and antiglutamatergic drug caramiphen reduces seizure duration in soman-exposed rats: synergism with the benzodiazepine diazepam

Therapy of seizure activity following exposure to the nerve agent soman (GD) includes treatment with the anticonvulsant diazepam (DZP), an allosteric modulator of γ-aminobutyric acid A (GABA(A)) receptors. However, seizure activity itself causes the endocytosis of GABA(A) receptors and diminishes the inhibitory effects of GABA, thereby reducing the efficacy of DZP. Treatment with an N-methyl-d-aspartic acid (NMDA) receptor antagonist prevents this reduction in GABAergic inhibition. We examined the efficacy of the NMDA receptor antagonist caramiphen edisylate (CED; 20mg/kg, im) and DZP (10mg/kg, sc), administered both separately and in combination, at 10, 20 or 30min following seizure onset for attenuation of the deleterious effects associated with GD exposure (1.2 LD(50); 132μg/kg, sc) in rats. Outcomes evaluated were seizure duration, neuropathology, acetylcholinesterase (AChE) activity, body weight, and temperature. We also examined the use of the reversible AChE inhibitor physostigmine (PHY; 0.2mg/kg, im) as a therapy for GD exposure. We found that the combination of CED and DZP yielded a synergistic effect, shortening seizure durations and reducing neuropathology compared to DZP alone, when treatment was delayed 20-30min after seizure onset. PHY reduced the number of animals that developed seizures, protected a fraction of AChE from GD inhibition, and attenuated post-exposure body weight and temperature loss independent of CED and/or DZP treatment. We conclude that: 1) CED and DZP treatment offers considerable protection against the effects of GD and 2) PHY is a potential therapeutic option following GD exposure, albeit with a limited window of opportunity.

Obtaining a ground-based lidar geometric form factor using coincident spaceborne lidar measurements

We present a method to determine the geometric form factor of a ground-based lidar using simultaneous lidar measurements made from the ground and from space. The theoretical basis is described. The feasibility of the method is demonstrated by applying it to the measurement data acquired by the Cloud Aerosol Lidar Infrared Pathfinder Satellite Observation (CALIPSO) lidar and a ground-based lidar located at the Hampton University (37.02 degrees N, 76.34 degrees W). The geometric factors with different aerosol conditions are retrieved.

Thermal compatibility of dental ceramic systems using cylindrical and spherical geometries

OBJECTIVE

To test the hypothesis that bilayer ceramic cylinders and spheres can provide valid confirmation of thermal incompatibility stresses predicted by finite element analyses.

METHODS

A commercial core ceramic and an experimental core ceramic were used to fabricate open-ended cylinders and core ceramic spheres. The core cylinders and spheres were veneered with one of four commercial dental ceramics representing four thermally compatible groups and four thermally incompatible groups. Axisymmetric thermal and viscoelastic elements in the ANSYS finite element program were used to calculate temperatures and stresses for each geometry and ceramic combination. This process required a transient heat transfer analysis for each combination to determine input temperatures for the structural model.

RESULTS

After fabrication, each specimen was examined visually using fiberoptic transillumination for evidence of cracking. There were 100% failures of the thermally incompatible cylinders while none of the thermally compatible combinations failed. Among the spheres, 100% of the thermally incompatible systems failed, 16% of one of the thermally compatible systems failed, and none of the remaining compatible combinations failed. The calculated stress values were in general agreement with the experimental observations, i.e., low residual stresses for the specimens that did not fail and high residual stresses for the specimens that did fail.

SIGNIFICANCE

Simple screening geometries can be used to identify highly incompatible ceramic combinations, but they do not identify marginally incompatible systems.

Patterns of variations in Escherichia coli strains that produce cytolethal distending toxin

A collection of 20 Escherichia coli strains that produce cytolethal distending toxin (CDT) were analyzed for their virulence-associated genes. All of these strains were serotyped, and multiplex PCR analysis was used to ascertain the presence of genes encoding other virulence factors, including Shiga toxin, intimin, enterohemolysin, cytotoxic necrotizing factor type 1 (CNF1) and CNF2, heat-stable toxin, and heat-labile toxin. These CDT-producing strains possessed various combinations of known virulence genes, some of which have not been noted before. Partial cdtB sequences were obtained from 10 of these strains, and their predicted CdtB sequences were compared to known E. coli CdtB sequences; some of the sequences were identical to known CdtB sequences, but two were not. PCR primers based on sequence differences between the known cdt sequences were tested for their ability to detect CDT producers and to determine CDT type. Correlations between the type of CDT produced, the presence of other virulence properties, and overall strain relatedness revealed that the CDT producers studied here can be divided into three general groups, with distinct differences in CDT type and in their complement of virulence-associated genes.

Interactions of Campylobacter jejuni cytolethal distending toxin subunits CdtA and CdtC with HeLa cells

Campylobacter jejuni produces a toxin, called cytolethal distending toxin (CDT), which causes direct DNA damage leading to invocation of DNA damage checkpoint pathways. The affected cells arrest in G(1) or G(2) and eventually die. CDT consists of three protein subunits, CdtA, CdtB, and CdtC, with CdtB recently identified as a nuclease. However, little is known about the functions of CdtA or CdtC. In this work, enzyme-linked immunosorbent assay-based experiments were used to show, for the first time, that both CdtA and CdtC bound with specificity to the surface of HeLa cells, whereas CdtB did not. Varying the order of the addition of subunits for reconstitution of the holotoxin had no effect on activity. In addition, mutants containing deletions of conserved regions of CdtA and CdtC were able to bind to the surface of HeLa cells but were not able to participate in holotoxin assembly. Finally, both Cdt mutant subunits were able to effectively compete with CDT holotoxin in the HeLa cell binding assay.

Campylobacter jejuni cytolethal distending toxin promotes DNA repair responses in normal human cells

Cytolethal distending toxin (CDT) is a multisubunit protein found in various gram-negative bacterial pathogens of humans which is thought to cause cell death by direct DNA damage of host cells. We sought to determine if a cellular response to DNA damage could be detected by exogenous addition of the holotoxin. Exogenous addition of the Campylobacter jejuni 81-176 CDT to primary human fibroblasts resulted in formation of Rad50 foci, which are formed around double-stranded-DNA breaks. Moreover, such foci are formed in both proliferating and nonproliferating cells that are treated with C. jejuni CDT. Fibroblasts that were intoxicated and later stimulated to proliferate failed to divide and remained arrested in the G(1) phase of the cell cycle.

Functional replacement of oxygen by other oxidants in articular cartilage

OBJECTIVE

Articular cartilage chondrocytes consume remarkably little O(2) in comparison with most other animal cells; glycolysis forms the principal source of ATP in this cartilage. Although not lethal for many days, imposition of anoxia immediately lowers intracellular ATP, inhibits rates of glycolysis, and prevents articular chondrocytes from producing extracellular matrix macromolecules. This study was undertaken to investigate the role of O(2) in articular chondrocyte metabolism.

METHODS

We examined the effects of oxygen and of several other classes of exogenous oxidants, i.e., 1) the dyes methylene blue and 2,6-dichlorophenol-indophenol, 2) the iron (III) complex ferricyanide, and 3) the keto-acids oxaloacetate and pyruvate (and phosphoenolpyruvate, a metabolic precursor of pyruvate), on rates of glycolysis and of sulfate incorporation by bovine articular cartilage in vitro.

RESULTS

Lactate production was lowest under conditions of anoxia and was stimulated severalfold by addition of O(2) (air-saturated medium). Under strict anoxia, other oxidants restored lactate production to rates at least comparable with those seen in aerobic controls; under aerobic conditions, they had little effect. Oxygen and all of the other oxidants examined stimulated sulfate incorporation more strongly than lactate production. The compounds that promoted glycolysis and hence sulfate incorporation in cartilage under anoxia were themselves reduced; that is, they functioned as oxidants in lieu of O(2).

CONCLUSION

For normal function, articular cartilage appears to require exogenous oxidants to stimulate glycolysis and produce ATP and extracellular matrix. Under physiologic conditions, oxygen acts as this oxidant, but its role can be adequately assumed by other agents.

The effect of mechanical stress on cartilage energy metabolism

Cartilage is routinely subjected to varying mechanical stresses which are known to affect matrix turnover by a variety of pathways. Here we show that mechanical loads which suppress sulphate incorporation or protein synthesis by articular chondrocytes, also inhibit rates of oxygen uptake and of lactate production. Although the mechanisms have not been definitively identified, it has been shown that high hydrostatic pressures reduce the activity of the glucose transporter GLUT. Furthermore, fluid expression consequent on static loading changes intracellular pH and ionic strength; intracellular changes which would reduce the activity of glycolytic enzymes. Both pathways would thus lead to a fall in rates of glycolysis and a reduction in intracellular ATP, and - since ATP concentrations directly affect sulphation of proteoglycans - a rapid fall in sulphate incorporation. Our results suggest that load-induced changes in matrix synthesis in cartilage can occur by means other than changes in gene expression.

The pathophysiology of the intervertebral disc

After a review of disk structure, the pivotal role of disk cells in producing and renewing the extracellular disk matrix is emphasized. Disk cells rely on nutrients that diffuse through the vertebral endplates. Microelectrode methods have been developed to study nutrient diffusion and endplate permeability. Mechanical stimuli modify disk cell activity. Scoliosis is associated with decreased endplate permeability, a factor that may play a role in disk degeneration and scoliosis progression.

Department of defense eye injuries from fiscal year 1988-1998

BACKGROUND

The U.S. Army Safety Center, U.S. Navy Safety Center, and U.S. Air Force Safety Center collect data on occupational injuries that occur in each respective military service.

METHODS

An 11-year retrospective study of ground eye injuries collected by the Army Safety Center, Navy Safety Center, and Air Force Safety Center, from Fiscal Year (FY) 1988 through FY 1998 was performed. Demographic data analyzed included rank, gender, age, and military/civilian status. Injury data analyzed included severity of injury, eye protection use, injury cost, work days lost due to injury, and days hospitalized due to injury.

RESULTS

Statistics for Department of Defense (DoD) eye injuries indicate the average military individual who sustains an eye injury is a 20- to 24-year-old male, E3-E5. This individual is not wearing eye protection and will lose an average of 5.9 days from work at a cost averaging $6,295. The average civil service employee who sustains an eye injury is a WG6-10 who is a 30- to 39-year-old male. This individual is not wearing eye protection and will lose an average of 3.5 days from work at a cost averaging $1,598. Statistically significant differences in the numbers of eye injuries were observed between military occupational groups. In addition, incidence rates between military occupational groups were statistically significant. Category 1, Infantry, Gun Crews, and Seamanship Specialists, has the highest count of injuries and Category 7, Craftsworkers, has the highest incidence.

CONCLUSIONS

Proactive vision conservation education at local levels needs to focus on these military occupational groups.

Cytolethal distending toxin demonstrates genotoxic activity in a yeast model

Cytolethal distending toxins (CDTs) are multisubunit proteins produced by a variety of bacterial pathogens that cause enlargement, cell cycle arrest, and apoptosis in mammalian cells. While their function remains uncertain, recent studies suggest that they can act as intracellular DNases in mammalian cells. Here we establish a novel yeast model for understanding CDT-associated disease. Expression of the CdtB subunit in yeast causes a G2/M arrest, as seen in mammalian cells. CdtB toxicity is not circumvented in yeast genetically altered to lack DNA damage checkpoint control or that constitutively promote cell cycle progression via mutant Cdk1, because CdtB causes a permanent type of damage that results in loss of viability. Finally, we establish that CDTs are likely to be potent genotoxins, as indicated by in vivo degradation of chromosomal DNA associated with expression of CdtB-suggesting that the varied distribution of CDT in bacteria implicates many human pathogens as possessors of genotoxic activity.

Fracture resistance of all-ceramic and metal-ceramic inlays

PURPOSE

Metal-ceramic inlay designs were developed to determine if the esthetic qualities of all-ceramic inlays could be duplicated and at the same time improve their strength and stability. The objectives of this study were to: (1) compare the fracture resistance of metal-ceramic inlays with that of all-ceramic inlays; (2) determine the correlation between the degree of preparation taper and fracture resistance; and (3) determine the correlation between marginal gap width and fracture resistance.

MATERIALS AND METHODS

Inlay preparations were made on 60 Dentoform teeth, with 30 teeth allocated for metal-ceramic inlays and 30 teeth for all-ceramic inlays. Each group was further subdivided into 5-, 10-, and 20-degree taper preparations. Metal-ceramic inlays were fabricated using Goldtech Bio 2000 metal and Ceramco porcelain extending to the margin, while all-ceramic inlays were made from Empress II ceramic. Marginal gap widths were measured at six critical areas after fabrication. The load at failure was measured using an Instron Universal Testing Machine.

RESULTS

The mean fracture load for all-ceramic inlays and metal-ceramic inlays at 5, 10, and 20 degrees was 70+/-40 N, 48+/-37 N, 33+/-7 N, and 40+/-23 N, 29+/-22 N, and 14+/-4 N, respectively. The mean gap width was 105 microm and 126 microm for all-ceramic and metal-ceramic inlays, respectively.

CONCLUSION

The mean fracture load for Empress inlays was significantly higher than that for metal-ceramic inlays. Inlays with a 5-degree taper were significantly more fracture resistant than those with a 20-degree taper. There was no relation between marginal gap width and fracture resistance.

The surgical spectrum of pulmonary neuroendocrine neoplasms

OBJECTIVES

The purpose of this study is to review our experience with the spectrum of neuroendocrine neoplasms of the lung with emphasis on the histopathologic classification and surgical therapy of each class of neoplasm.

DESIGN

This retrospective review covers the entire spectrum of neuroendocrine neoplasms of the lung over an 11-year period (January 1985 to December 1995) in a university hospital setting. Only patients who underwent surgical resection were included in this review.

PATIENTS

During this period, a total of 77 patients underwent lung resection for the following neuroendocrine neoplasms: typical carcinoid (TC), 50 patients; atypical carcinoid (AC), 5 patients; large cell neuroendocrine carcinoma (LCNEC), 9 patients; mixed large-small cell neuroendocrine carcinoma (LSNEC), 4 patients; or small cell neuroendocrine carcinoma (SCC), 9 patients. There were 37 men (48.1%) and 40 women (51.9%) among the patients, with a mean age of 57.9 years (range, 14 to 87 years).

INTERVENTIONS

Primary surgical resection consisted of the following procedures: 52 lobectomies (67.5%); 10 pneumonectomies (13%); 13 limited resections (16.9%); 1 left main bronchus sleeve resection; and 1 carinal resection. Six patients had the following concomitant procedures: pericardiectomy, 2 patients; mediastinoscopy, 1 patient; chest wall resection, 1 patient; stapling blebs, 1 patient; and transdiaphragmatic liver biopsy, 1 patient. Four patients underwent bilobectomies, and two patients underwent multiple wedge resections.

RESULTS

The hospital mortality rate was 2.6% (2 of 77 patients), and both patients died of pulmonary failure. Follow-up was obtained in 62 of 77 patients (80.9%) for an average of 38.1 months (range, 2 to 132 months). There were a total of 13 deaths, and 8 were disease-related (LCNEC, 4 deaths; SCC, 2 deaths; LSNEC, 1 death; and AC tumor, 1 death. The mean disease-free intervals for patients with these neoplasms were the following: TC tumor, 41.3 months; AC tumor, 20 months; LCNEC, 20.4 months; LSNEC, 25 months; and SCC, 48 months. The overall 3-year survival rate was 45.2% (28 of 62 patients).

CONCLUSION

This report will emphasize the classification, surgical management, and treatment considerations of pulmonary neuroendocrine neoplasms. Despite the poor overall prognosis in high-grade neuroendocrine tumors of the lung, surgery remains a viable adjunct in the early stages of this disease.

A phase II trial of anastrozole in advanced recurrent or persistent endometrial carcinoma: a Gynecologic Oncology Group study

BACKGROUND

Some endometrial cancers are hormonally dependent. A principal source of circulating estrogen is conversion of adrenal androstenedione by aromatase. Anastrozole (Arimidex) is an oral nonsteroidal aromatase inhibitor which is active in recurrent breast cancer. This Phase II study was undertaken to evaluate anastrozole in recurrent endometrial carcinoma.

METHODS

Patients with advanced or recurrent endometrial cancer not curable with either surgery or radiation therapy and with measurable disease, a GOG (Zubrod) performance status of < or = 2, no more than one prior hormonal therapy regimen, and no prior chemotherapy were eligible. Anastrozole was administered at a dose of 1 mg/day orally for at least 28 days.

RESULTS

Twenty-three patients were entered on this trial. On central pathology review, 9 of them had grade 2 and 14 had grade 3 tumors. One to 24 courses (median: 1) of therapy were administered. Two partial responses were noted (9%; 90% confidence interval 3 to 23%). Two additional patients had short-term stable disease. With the exception of 1 case of venous thrombosis, the toxicity profile was mild. Median durations of progression-free survival and overall survival are 1 and 6 months, respectively.

CONCLUSIONS

Anastrozole has minimal activity in an unselected population of patients with recurrent endometrial cancer.

Intratracheal instillation of zinc-cadmium sulfide (ZnCdS) in Fischer 344 rats

The purpose of this study was to assess the bioavailability and pulmonary toxicity of ZnCdS in rats. Groups of 30 male Fischer 344 rats each were anesthetized and dosed via intratracheal instillation with 5 mg of either ZnCdS, quartz (positive control), or titanium dioxide (TiO(2), negative control) suspended in 0.5 ml saline. A vehicle control group received 0.5 ml saline. Ten animals from each test group were sacrificed at 1 day, 1 wk, and 14 wk after dosing for bronchoalveolar lavage fluid (BALF) analysis and histopathology. The BALF was analyzed for alkaline phosphatase, acid phosphatase, lactate dehydrogenase (LDH), beta-glucuronidase (beta-glu), total protein, and cell counts. Two separate groups of 24 rats each were dosed as already described with either ZnCdS or saline. Eight rats from each group were sacrificed at 1 day, 1 wk, and 14 wk after dosing for determination of cadmium (Cd) and zinc (Zn) concentrations in the lung, liver, kidney, and blood. Results indicate that at 1 day after dosing, all enzyme activities (except acid phosphatase) and cell counts in BALF from the quartz and ZnCdS groups were significantly higher than in the TiO(2) and saline groups. At 7 days after dosing, high enzyme activity persisted in the quartz group, while the ZnCdS group showed only LDH and total protein levels significantly higher than the saline group. At 14 wk after dosing, LDH, total protein, beta-glu, and cell counts in the quartz group were significantly higher than all other groups. Histologic examination revealed interstitial inflammation and accumulation of foreign material in the lungs and mediastinal lymph nodes of quartz-, TiO(2)-, and ZnCdS-treated rats. Metal analyses in tissues showed profuse Cd and Zn concentrations in the lung 1 day after dosing, followed by a successive decline at 7 days and 14 wk after dosing. A very small, but statistically significant, amount of Cd and Zn was found in the kidneys at 14 wk after dosing. In conclusion, ZnCdS appears to cause temporary lung inflammation, is cleared slowly, and is poorly bioavailable.

Surgical palliation of airway obstruction resulting from lung cancer

Bronchogenic carcinoma remains a relentless plague of modern society causing far more deaths than the well-popularized "AIDS epidemic" and secondary only to cardiovascular disease as a cause of death in America. Despite medical advances and treatment breakthroughs, only 40% of newly identified lung cancer patients are "potentially curable". Therefore, a large portion of this patient population will require palliative care and treatment. Surgical palliation is somewhat a misnomer in that most endobrachial lesions causing significant obstruction that result in dyspnea are not amenable to surgical intervention, i.e., operative resectional therapy. The palliative management options of airway obstruction resulting from advanced stage lung cancer will be reviewed, including the historical aspects, development and current use of laser resection, airway stenting, and endobrachial brachytherapy for management of unresectable airway tumors. These modalities frequently are used simultaneously in the same patient and may be used in conjunction with current chemotherapeutic and conventional external-beam radiation protocols.

A randomized comparison of indwelling pleural catheter and doxycycline pleurodesis in the management of malignant pleural effusions

BACKGROUND

The purpose of this study was to compare the effectiveness and safety of a chronic indwelling pleural catheter with doxycycline pleurodesis via tube thoracostomy in the treatment of patients with recurrent symptomatic malignant pleural effusions (MPE).

METHODS

In this multi-institutional study conducted between March 1994 and February 1997, 144 patients (61 men and 83 women) were randomized in a 2:1 distribution to either an indwelling pleural catheter or doxycycline pleurodesis. Patients receiving the indwelling catheter drained their effusions via vacuum bottles every other day or as needed for relief of dyspnea.

RESULTS

The median hospitalization time was 1.0 day for the catheter group and 6.5 days for the doxycycline group. The degree of symptomatic improvement in dyspnea and the quality of life was comparable in each group. Six of 28 patients who received doxycycline (21%) had a late recurrence of pleural effusion, whereas 12 of 91 patients who had an indwelling catheter (13%) had a late recurrence of their effusions or a blockage of their catheter after the initially successful treatment (P = 0.446). Of the 91 patients sent home with the pleural catheter, 42 (46%) achieved spontaneous pleurodesis at a median of 26.5 days.

CONCLUSIONS

A chronic indwelling pleural catheter is an effective treatment for the management of patients with symptomatic, recurrent, malignant pleural effusions. When compared with doxycycline pleurodesis via tube thoracostomy, the pleural catheter requires a shorter hospitalization and can be placed and managed on an outpatient basis.

Comparison of hematologic consequences and efficacy of p-aminophenones in mice

Controlled methemoglobin (MHb) formation is one strategy employed to counter cyanide (CN) toxicity. Currently available MHb formers present certain drawbacks and limitations. The purpose of this study was to characterize, in mice, the hematologic effects of the MHb-forming compound p-aminopropiophenone (PAPP), and two structurally-related p-aminophenones, p-aminoheptanoylphenone (PAHP) and p-aminooctanoylphenone (PAOP). Although these three p-aminophenones have been shown previously to be efficacious as pretreatments against CN, a more complete understanding of their hematologic effects is lacking. In addition, because the active form of PAPP has been shown to be its N-hydroxy metabolite, the N-hydroxy metabolites of PAPP, PAHP and PAOP were also tested. Using a hemoximeter, blood samples obtained -2 to +180 min relative to intramuscular (i.m.) or intraperitoneal (i.p.) drug injections were evaluated. Sodium nitrite (NaNO(2)) and the appropriate solvents served as the positive and negative controls, respectively. Dose-, time-, route-, and compound-related effects were observed. MHb and sulfhemoglobin levels increased, whereas levels of those parameters related to oxygen-carrying capacity of the blood, such as, oxygen saturation and oxyhemoglobin decreased. In general, the effects of PAHP and PAOP were longer lasting than those of PAPP and NaNO(2). Furthermore, PAPP and NaNO(2) were equally effective with either route of administration. Conversely, PAHP and PAOP showed larger effects when administered i.p. versus i.m. The animals treated with N-hydroxy metabolites of the p-aminophenones also showed similar changes in the hematological parameters measured. N-hydroxy PAPP was shown to be the most rapidly acting MHb-forming compound examined in this series. It could achieve therapeutic concentrations of MHb within 2 min and thus may be considered as a treatment for CN intoxication. Although additional work is needed, these data provide information that will be useful for the successful development of improved anti-CN MHb formers.

Cutaneous uptake of 14C-HD vapor by the hairless guinea pig

The hairless guinea pig (HGP) is used by our laboratory to model the human cutaneous response to sulfur mustard (HD), bis(2-chloroethylsulfide), exposure. We determined the HD content in the skin of HGP after a 7-min exposure to vapors saturated with a mixture of HD and 14C-HD. Concentration/time (CT) values in the range of 2 micrograms/cm2/min were determined by counting skin 14C disintegrations per min (dpm) in animals euthanized immediately after exposure. These values are similar to human penetration rates obtained by other investigators. A rate curve monitoring the reduction in skin 14C dpm was developed for animals euthanized between 0 and 24 hr post- exposure. This curve showed the greatest change after 1 hr. The epidermal (62%) to dermal (38%) ratio of 14C at 24 hr was measured for two animals. We saw no site preference for HD penetration among the 8 sites used. The 14C content of template adhesive tape was determined to follow HD distribution. These results contribute to a better understanding of the cutaneous response to HD in the HGP model.

Evaluation of treatment modalities for thoracic empyema: a cost-effectiveness analysis

BACKGROUND

Empyema thoracis is treated with a multitude of therapeutic options. Optimal therapy and cost-containment requires selection of the most appropriate initial intervention.

METHODS

A retrospective review of treatment modalities was performed on 77 patients diagnosed with empyema thoracis from 1990 to 1997 at one institution. Mean age was 59 years (range, 21 to 90 years); 52 were men and 25 were women.

RESULTS

Sixty-five percent (50/77) were parapneumonic and 68% (52/77) were multiloculated. Treatment modalities were as follows: group 1, antibiotics only (n = 4); group 2, primary intervention: image-directed catheter (n = 20) or tube thoracostomy (n = 24); and group 3, secondary intervention: decortication (n = 17), rib resection or muscle interposition (n = 12). Thirty-four percent (9/20 image-directed catheter and 8/24 tube thoracostomy) had failure of initial intervention. Patients undergoing decortication more often had multiloculated empyema thoracis (16 of 17) compared with those undergoing image-directed catheters (8 of 20) or tube thoracotomy (16 of 24). Length of stay was reduced for decortication patients (17 days) compared with those having image-directed catheters (21.8 days), failed image-directed catheters (29.7 days), or tube thoracostomies (19.6 days). Hospital charges per patient between decortication and image-directed catheter ($34,770.79 versus $37,869.41) were comparable, but charges were significantly decreased in decortication patients as compared with failed image-directed catheters ($55,609.32; p < 0.05).

CONCLUSIONS

Our series revealed that early decortication has charges similar to those of primary intervention (image-directed catheter or tube thoracostomy) but is more cost-effective than failed image-directed catheter. We advocate the use of early surgical intervention as the most optimal and cost-effective initial modality for the treatment of empyema thoracis.

Cognitive screening examinations for silent cerebral infarcts in sickle cell disease

OBJECTIVE

In children with sickle cell disease (SCD), silent cerebral infarcts are the most frequent cause of neurologic injury. We determined the sensitivity and specificity of selective neurocognitive measures when separating children with silent cerebral infarcts and SCD from sibling controls. Additionally, we tested the validity of the same cognitive measures to identify patients with overt strokes.

METHODS

We examined performance on a neuropsychologic battery containing measures of attention/executive, spatial, language, memory, and motor functioning for seven children with SCD and silent cerebral infarct, 21 children with SCD and overt stroke, and 17 normal siblings. Diagnosis of cerebral infarct was based on results of MRI.

RESULTS

Measures from the attention and executive domains were the most useful for identifying children with silent cerebral infarct. The Test of Variables of Attention was the most robust measure and yielded a sensitivity rate of 86% and a specificity rate of 81%. This measure also showed a sensitivity rate of 95% in identifying overt stroke.

CONCLUSIONS

Brief cognitive screening measures, if properly constructed, may be an effective means of identifying children with silent cerebral infarct. Future prospective studies should be pursued to assess the utility of cognitive screening for silent cerebral infarcts in SCD.

Pruritus in HIV-1 disease: therapy with drugs which may modulate the pattern of immune dysregulation

BACKGROUND

Pruritus in HIV-1+ patients is common and increases with disease progression. The causes of pruritus are numerous including xerosis, drug and photoeruptions, follicular and papular eruptions as well as infestations and infections by a wide range of organisms. One other possible factor contributing to pruritus is the pattern of immune dysregulation. With advancing HIV-1 disease there is Th1 to Th2 cytokine switching.

METHODS

After some positive results with prostaglandin inhibitors, we undertook a study in which we randomly placed patients on four different forms of therapy for their pruritus. The therapies included hydroxyzine with or without doxepin at night, pentoxifylline, indomethacin and topical moisturization with medium-strength topical steroids. All patients were evaluated for both subjective relief as well as side effects.

RESULTS

Patients placed on indomethacin obtained relief more consistently and more completely. Patients on pentoxifylline had the fewest side effects of all oral therapies. Patients on antihistamines with or without doxepin had the highest incidence of side effects, although more of these patients reported a greater degree of relief than patients on pentoxifylline. All patients on oral therapy overall had greater relief than patients using topical steroids.

CONCLUSION

The systemic therapies which may modulate the pattern of immune dysregulation seen in HIV-1 disease may be beneficial in the pruritus seen in late-stage patients.

Pathologic findings in lung volume reduction surgery

PURPOSE

Lung volume reduction surgery (LVRS) has re-emerged as an alternative in the management of patients with chronic, debilitating, emphysematous lung disease. This has permitted the formal evaluation of pathologic pulmonary changes present in these patients. This study seeks to describe systematically the pathologic findings present in patients undergoing LVRS.

METHODS

Tissue sections stained with hematoxylin-eosin, as well as special stains, were retrospectively reviewed from the specimens of 65 nonconsecutive LVRS patients (male patients, 66%; female patients, 31%; mean age, 63.2+/-6.76 yr). All operations were conducted via an open technique (bilateral, 83%; unilateral, 17%).

RESULTS

Histologic emphysema grade was mild in 9%, moderate in 72%, and severe in 19% of patients. Microscopic bullae were noted in 75% of specimens. Three patients, each with radiographic evidence of a lesion preoperatively, had small (1.1 to 2.8 cm) adenocarcinomas. Granulomatous bronchiolitis and pneumonitis were noted in one patient who postoperatively developed progressive respiratory compromise. An old, inactive aspergilloma was found in the specimen of another patient. Additional findings of potential clinical significance included bronchiolitis (54), bronchiolectasis (6), and bronchoalveolar metaplasia (1). Incidental findings included interstitial fibrosis and scar (55), interstitial inflammation (20), calcification (20), and ossification (11), bone marrow emboli (4), chemodectoma (2), and carcinoid tumorlets (1).

CONCLUSION

This systematic analysis of the resected specimens from patients undergoing LVRS describes a wide range of pathologic findings, including those clinically relevant, as well as incidental. As the application of LVRS continues to expand, the likelihood of discovering clinically significant pathologic lesions (eg, carcinoma) will undoubtedly increase.

Esophagectomy for cancer

We are faced with the challenge of treating, palliating, or curing esophageal cancer, considered by some to be the most insidious of cancers. This article acquaints the reader with historic milestones regarding resection of esophageal cancer, preoperative evaluation and preparation, and the various techniques currently being used to perform esophagectomy for cancer.

Belsey Mark IV antireflux procedure for complicated gastroesophageal reflux disease

BACKGROUND

Over the past 20 years, medical management of gastroesophageal reflux disease has met with increasing success, but a proportion of patients continue to have symptoms or complications requiring surgical treatment. The variety of operations available attests to the general lack of satisfaction with any single procedure.

METHODS

A retrospective study was conducted of 276 patients who underwent the Belsey Mark IV antireflux procedure at our institution between 1979 and 1995. The indication for operation was gastroesophageal reflux disease refractory to medical therapy in 137 patients, gastroesophageal reflux disease with symptomatic stricture or Schatzki's ring in 36, achalasia or epiphrenic diverticulum in 74, paraesophageal hernia in 27, and esophageal mass in 2. Fifteen patients (5.4%) had undergone prior antireflux operations.

RESULTS

There was one perioperative death (0.4%) resulting from an apparent myocardial infarction in an 87-year-old woman who underwent operation for paraesophageal hernia with volvulus. Two patients had contained leaks diagnosed by routine postoperative contrast studies; both were managed successfully without operation. Two patients required early reoperation for recurrent symptoms: 1 underwent a repeated Belsey Mark IV procedure and the other underwent an esophagogastrectomy. An additional 7 patients experienced late recurrence of symptoms requiring surgical management. The overall complication rate was 10.1%, with minor pulmonary complications (2.1%) and atrial arrhythmias (1.8%) occurring most commonly.

CONCLUSIONS

The Belsey Mark IV procedure is a safe and effective operation for the management of gastroesophageal reflux disease with complications, and it compares favorably with other antireflux procedures.

Traumatic injury of the cervicothoracic trachea and major bronchi

Interstate highways and crowded urban areas have become the "battlefields" of the 1990s. The weapons are motor vehicles, handguns, and knives. This article relates the historical perspective, diagnosis, and management of traumatic injury to the cervicothoracic trachea and major bronchi. The etiologic factors are explained in depth. Examples of the current management of cervicothoracic tracheal injuries, including resection, primary repair, and the use of autogenous tissue to buttress or wrap the repair, are explained and illustrated.

Evidence for a negative Pasteur effect in articular cartilage

Uptake of external glucose and production of lactate were measured in freshly-excised bovine articular cartilage under O2 concentrations ranging from 21% (air) to zero (N2-bubbled). Anoxia (O2 concentration < 1% in the gas phase) severely inhibited both glucose uptake and lactate production. The decrease in lactate formation correlated closely with the decrease in glucose uptake, in a mole ratio of 2:1. This reduction in the rate of glycolysis in anoxic conditions is seen as evidence of a negative Pasteur effect in bovine articular cartilage. Anoxia also suppressed glycolysis in articular cartilage from horse, pig and sheep. Inhibitors acting on the glycolytic pathway (2-deoxy-D-glucose, iodoacetamide or fluoride) strongly decreased aerobic lactate production and ATP concentration, consistent with the belief that articular cartilage obtains its principal supply of ATP from substrate-level phosphorylation in glycolysis. Azide or cyanide lowered the ATP concentration in aerobic cartilage to approximately the same extent as did anoxia but, because glycolysis (lactate production) was also inhibited by these treatments, the importance of any mitochondrial ATP production could not be assessed. A negative Pasteur effect would make chondrocytes particularly liable to suffer a shortage of energy under anoxic conditions. Incorporation of [35S]sulphate into proteoglycan was severely curtailed by treatments, such as anoxia, which decreased the intracellular concentration of ATP.

Radiologic evaluation and intervention for empyema thoracis

Empyema thoracis has changed little in its presentation and etiology since first described. Surgical intervention, simply put, is "drainage of pus." The introduction of computed tomography and catheter drainage of empyema is the first technologically driven advancement for the management of empyema. The use of various radiologic procedures for characterization and treatment of empyema is described.

Lung volume reduction surgery: lessons learned

BACKGROUND

The concept of lung volume reduction for generalized emphysema was proposed by Brantigan and associates in 1958 and reintroduced by Cooper and colleagues in 1994. The present study presents lessons learned from an 18-month experience.

METHODS

From August 1, 1994, to August 1, 1995, 53 patients underwent lung volume reduction at Emory University for generalized emphysema. There were 17 women and 36 men ranging in age from 55 to 75 years. The length of stay ranged from 10 to 59 days. At the time of presentation, 47 patients were receiving oxygen and 35 were receiving steroids. Forty-six patients were operated on using a median sternotomy and 7 through a unilateral thoracotomy. All patients underwent preoperative and postoperative pulmonary rehabilitation.

RESULTS

There was one early death and four late deaths. Lessons learned from this group of patients are presented.

CONCLUSIONS

Lung volume reduction surgery remains a sea of relatively uncharted waters, with the future direction yet to be determined.

Role of transesophageal echocardiography in the management of patients with bronchogenic carcinoma invading the left atrium

TEE played a significant role in the management of 2 patients by defining the extent of cardiac invasion. We believe TEE would be helpful in patients presenting with thoracic tumors believed to be encroaching on cardiac structures, where consideration is being given to surgical resection of the tumor.

Tracheal resections: lessons learned

Tracheal resection and primary anastomosis can be performed for the management of congenital, traumatic, iatrogenic, and neoplastic etiologies of tracheal stenosis. During a 19-year period, we performed 45 tracheal resections on 38 patients with low operative mortality (7.9%) and morbidity. One patients had congenital tracheal stenosis (group 1); 4 patients had stenosis resulting from traumatic lesions (group 2); 18 patients had stenosis caused by tracheostomy or endotracheal tubes (group 3); and 15 patients had stenosis caused by a variety of neoplastic lesions (nine primary and six secondary) (group 4). Preoperative evaluation and surgical and anesthesia management are described. Eight tracheal stents were used (three Neville prostheses and five Montgomery T tubes). Disastrous results occurred with the Neville prosthesis, but acceptable results were obtained when the Montgomery T tube was used. There were several "lessons learned" during the evolution of this series. Chest roentgenograms are not useful. Tracheal tomography and computed tomography are extremely informative in evaluation of iatrogenic and neoplastic lesions. Proper mobilization allows primary anastomosis after almost all resections. Excellent results were obtained with iatrogenic lesions. Increased mortality and morbidity occur in patients undergoing resection for neoplastic lesions; however, 5-year survival is good, and results are gratifying.

Hemorrhagic shock in endotoxin-resistant mice: improved survival unrelated to deficient production of tumor necrosis factor

Although tumor necrosis factor (TNF) has been implicated in sepsis-induced mortality, its role in the pathophysiology of hemorrhagic shock (HS) remains ill defined. We studied three groups of acutely anesthetized mice undergoing HS to determine the role of TNF in HS mortality. Shock was initiated in each group after heparinization by arterial bleeding of 4 mL/100 g body weight followed by 12 mL/100 g body weight resuscitation with normal saline at 1 hour. The C3H/HeJ mice (n = 14), characterized by a genetic defect in macrophage production of TNF and other cytokines in response to endotoxin, were compared with the closely related C3H/HeN strain (n = 18), which do produce TNF. A second group of C3H/HeN mice were passively immunized to TNF by pretreatment with 2.5 mg/kg anti-murine TNF antibody (Ab) before HS. In contrast to the high TNF levels measured following HS in C3H/HeN controls, post-HS TNF was undetectable in C3H/HeJ mice. Five-day survival rate and survival time were significantly greater in C3H/HeJ mice when compared with C3H/HeN controls. Anti-TNF Ab pretreatment of C3H/HeN mice abolished the increase in TNF but did not improve survival. The data demonstrate a striking improvement in survival of TNF-deficient C3H/HeJ mice following severe HS. However, the improved survival does not appear to result from deficient TNF production, since Ab pretreatment did not decrease HS mortality. The improved survival in C3H/HeJ mice suggests that cytokines other than TNF may play a role in the pathophysiology of HS.

Intraperitoneal P-32 is not an effective consolidation therapy after a negative second-look laparotomy for epithelial carcinoma of the ovary

Thirty-four patients with epithelial carcinoma of the ovary were entered into a trial of adjuvant intraperitoneal P-32 following induction chemotherapy and a negative second-look laparotomy. The breakdown by initial Stage was Stage IC, 5; Stage II, 3; Stage III optimal, 22; and Stage III suboptimal, 4. Previous treatment consisted of 4-12 cycles (median 6) of cisplatin or carboplatin-based combination chemotherapy. Fifteen millicuries of P-32 were instilled via a Tenckhoff catheter placed at the time of second-look laparotomy. Because of a 22% incidence of bowel injury in the first 23 patients, the P-32 dose was reduced to 12 mCi in the last 11 patients. To date, there have been no bowel injuries at the lower dose. Eighteen of the 34 (53%) patients have relapsed with a median time to relapse of 20 months and a median follow-up for all patients of 31 months. There has been no difference in the relapse rate between a dose of 12 and 15 mCi. Intraperitoneal P-32 does not appear to reduce the relapse rate following a negative second-look laparotomy. The incidence of bowel injury is dose dependent and is higher than that seen in patients treated as an adjuvant following initial surgery without subsequent chemotherapy or second-look laparotomy.

Characterizations of the mirror attenuator mosaic: solar diffuser plate

The mirror attenuator mosaic (MAM), a solar diffuser plate, was used for the flight calibration of the broadband shortwave (0.2-5-microm) and total (0.2 to >200-microm) Earth Radiation Budget Experiment scanning thermistor bolometer radiometers. The MAM solar-reflecting surface cosisted of a tightly packed array of vacuum-deposited aluminum, concave spherical mirrors, while its solar-absorbing surface consisted of black chrome. The effective reflectance of the MAM was constant to within +/-2% after almost 2 years in orbit, a marked improvement over earlier solar diffusers.

Strengthening of feldspathic porcelain by ion exchange and tempering

This study investigated the effectiveness of tempering and ion-exchange treatments on crack growth and bi-axial flexural strength of seven feldspathic porcelains. The results showed that tempering treatment was more effective in strengthening porcelain than was the ion-exchange process as measured by the bi-axial flexural strength. However, the results of initial crack size induced by a microhardness tester showed that ion-exchange yielded a surface that was more resistant to crack initiation than was that yielded by the tempering treatment. EDX and microprobe analyses showed that there was evidence of exchange between Na+ within the porcelain surface and K+ from the ion-exchange agent applied on the surface.