Evaluation of Ortho VITROS and Roche Elecsys S and NC Immunoassays for SARS-CoV-2 Serosurveillance Applications

SARS-CoV-2 seroprevalence studies are instrumental in monitoring epidemic activity and require well-characterized, high-throughput assays, and appropriate testing algorithms. The U.S. Nationwide Blood Donor Seroprevalence Study performed monthly cross-sectional serological testing from July 2020 to December 2021, implementing evolving testing algorithms in response to changes in pandemic activity. With high vaccine uptake, anti-Spike (S) reactivity rates reached >80% by May 2021, and the study pivoted from reflex Roche anti-nucleocapsid (NC) testing of Ortho S-reactive specimens to parallel Ortho S/NC testing. We evaluated the performance of the Ortho NC assay as a replacement for the Roche NC assay and compared performance of parallel S/NC testing on both platforms. Qualitative and quantitative agreement of Ortho NC with Roche NC assays was evaluated on preselected S/NC concordant and discordant specimens. All 190 Ortho S+/Roche NC+ specimens were reactive on the Ortho NC assay; 34% of 367 Ortho S+/Roche NC- specimens collected prior to vaccine availability and 43% of 37 Ortho S-/Roche NC+ specimens were reactive on the Ortho NC assay. Performance of parallel S/NC testing using Ortho and Roche platforms was evaluated on 200 specimens collected in 2019 and 3,903 study specimens collected in 2021. All 200 pre-COVID-19 specimens tested negative on the four assays. Cross-platform agreement between Roche and Ortho platforms was 96.4% (3,769/3,903); most discordant results had reactivity close to the cutoffs on the alternate assays. These findings, and higher efficiency and throughput, support the use of parallel S/NC testing on either Roche or Ortho platforms for large serosurveillance studies. IMPORTANCE Seroprevalence studies like the U.S. Nationwide Blood Donor Seroprevalence Study (NBDS) have been critical in monitoring SARS-CoV-2 epidemic activity. These studies rely on serological assays to detect antibodies indicating prior infection. It is critical that the assays and testing algorithms used in seroprevalence studies have adequate performance (high sensitivity, high specificity, ability to discriminate vaccine-induced and infection-induced antibodies, etc.), as well as appropriate characteristics to support large-scale studies, such as high throughput and low cost. In this study we evaluated the performance of Ortho's anti-nucleocapsid assay as a replacement for the Roche anti-nucleocapsid assay and compared performance of parallel anti-spike and anti-nucleocapsid testing on both platforms. These data demonstrate similar performance of the Ortho and Roche anti-nucleocapsid assays and that parallel anti-spike and anti-nucleocapsid testing on either platform could be used for serosurveillance applications.

Frequent detection but lack of infectivity of SARS-CoV-2 RNA in pre-symptomatic, infected blood donor plasma

Respiratory viruses such as influenza do not typically cause viremia; however, SARS-CoV-2 has been detected in the blood of COVID-19 patients with mild and severe symptoms. Detection of SARS-CoV-2 in blood raises questions about its role in pathogenesis as well as transfusion safety concerns. Blood donor reports of symptoms or a diagnosis of COVID-19 after donation (post-donation information, PDI) preceded or coincided with increased general population COVID-19 mortality. Plasma samples from 2,250 blood donors who reported possible COVID-19–related PDI were tested for the presence of SARS-CoV-2 RNA. Detection of RNAemia peaked at 9%–15% of PDI donors in late 2020 to early 2021 and fell to approximately 4% after implementation of widespread vaccination in the population. RNAemic donors were 1.2- to 1.4-fold more likely to report cough or shortness of breath and 1.8-fold more likely to report change in taste or smell compared with infected donors without detectable RNAemia. No infectious virus was detected in plasma from RNAemic donors; inoculation of permissive cell lines produced less than 0.7–7 plaque-forming units (PFU)/mL and in susceptible mice less than 100 PFU/mL in RNA-positive plasma based on limits of detection in these models. These findings suggest that blood transfusions are highly unlikely to transmit SARS-CoV-2 infection.

How do we…form and coordinate a national serosurvey of SARS-CoV-2 within the blood collection industry?

Background

A national serosurvey of U.S. blood donors conducted in partnership with the Centers for Disease Control and Prevention (CDC) was initiated to estimate the prevalence of SARS‐CoV‐2 infections and vaccinations.

Methods

Beginning in July 2020, the Nationwide Blood Donor Seroprevalence Study collaborated with multiple blood collection organizations, testing labs, and leadership from government partners to capture, test, and analyze approximately 150,000 blood donation specimens per month in a repeated, cross‐sectional seroprevalence survey.

Results

A CDC website (https://covid.cdc.gov/covid-data-tracker/#nationwide-blood-donor-seroprevalence) provided stratified, population‐level results to public health professionals and the general public.

Discussion

The study adapted operations as the pandemic evolved, changing specimen flow and testing algorithms, and collecting additional data elements in response to changing policies on universal blood donation screening and administration of SARS‐CoV‐2 spike‐based vaccines. The national serosurvey demonstrated the utility of serosurveillance testing of residual blood donations and highlighted the role of the blood collection industry in public–private partnerships during a public health emergency.

Anatomical reconstruction of proximal coronary artery stenosis in children

OBJECTIVES

Timing and method of surgical reconstruction for non-sclerotic proximal coronary artery stenosis, occuring de-novo or post coronary artery transfer, are evolving. We have pursued a technique of anatomical reconstruction of ostial and short segment proximal coronary artery stenosis and atresia in children, using patch plasty or interposition vein graft. Herein, we discuss the medium- to long-term outcome.

METHODS

Nine consecutive children undergoing ten left main coronary artery reconstructions using autologous great saphenous vein patch (n = 4), autologous pericardium (n = 4), xenopericardium (n = 1) or great saphenous vein interposition graft (n = 1) were retrospectively analysed. Complementary wedge resection of the stenotic coronary ostium was performed in chronic cases.

RESULTS

The aetiology of coronary artery stenosis was post arterial switch operation (n = 6), Takayasu`s arteritis (n = 1), idiopathic left main coronary artery atresia (n = 1) and anomalous origin of the left coronary artery from the pulmonary artery (n = 1). Median age and weight at operation were 0.15 (range 0.01-13.1) years and 4.4 (range 3 -13.1) kilograms, respectively. Survival was 100% at median follow-up of 12.6 (range 1-19.2) years. All patients showed normal left ventricular ejection fraction on transthoracic echocardiogram. In one patient, kinking of the proximal left circumflex artery resulted in non-significant obstruction. In all other cases, follow-up catheter angiography revealed unobstructed coronary arteries. Cardiac magnetic resonance tomography showed no significant perfusion deficit in any child.

CONCLUSIONS

Anatomical reconstruction of the proximal left coronary artery using autologous saphenous vein may allow optimal restoration of physiological coronary blood flow, keeping the option of future coronary bypass operation open.

Use of US Blood Donors for National Serosurveillance of Severe Acute Respiratory Syndrome Coronavirus 2 Antibodies: Basis for an Expanded National Donor Serosurveillance Program

BACKGROUND

The Recipient Epidemiology and Donor Evaluation Study-IV-Pediatric (REDS-IV-P) Epidemiology, Surveillance and Preparedness of the Novel SARS-CoV-2 Epidemic (RESPONSE) seroprevalence study conducted monthly cross-sectional testing for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibodies in blood donors in 6 US metropolitan regions to estimate the extent of SARS-CoV-2 infections over time.

METHODS

During March-August 2020, approximately ≥1000 serum specimens were collected monthly from each region and tested for SARS-CoV-2 antibodies using a well-validated algorithm. Regional seroprevalence estimates were weighted based on demographic differences compared with the general population. Seroprevalence was compared with reported coronavirus disease 2019 (COVID-19) case rates over time.

RESULTS

For all regions, seroprevalence was <1.0% in March 2020. New York, New York, experienced the biggest increase (peak seroprevalence, 15.8% in May). All other regions experienced modest increases in seroprevalence (1%-2% in May-June to 2%-4% in July-August). Seroprevalence was higher in younger, non-Hispanic black, and Hispanic donors. Temporal increases in donor seroprevalence correlated with reported case rates in each region. In August, 1.3-5.6 estimated cumulative infections (based on seroprevalence data) per COVID-19 case were reported to the Centers for Disease Control and Prevention.

CONCLUSIONS

Increases in seroprevalence were found in all regions, with the largest increase in New York. Seroprevalence was higher in non-Hispanic black and Hispanic than in non-Hispanic white blood donors. SARS-CoV-2 antibody testing of blood donor samples can be used to estimate the seroprevalence in the general population by region and demographic group. The methods derived from the RESPONSE seroprevalence study served as the basis for expanding SARS-CoV-2 seroprevalence surveillance to all 50 states and Puerto Rico.

Evaluation of Commercially Available High-Throughput SARS-CoV-2 Serologic Assays for Serosurveillance and Related Applications

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) serosurveys can estimate cumulative incidence for monitoring epidemics, requiring assessment of serologic assays to inform testing algorithm development and interpretation of results. We conducted a multilaboratory evaluation of 21 commercial high-throughput SARS-CoV-2 serologic assays using blinded panels of 1,000 highly characterized specimens. Assays demonstrated a range of sensitivities (96%–63%), specificities (99%–96%), and precision (intraclass correlation coefficient 0.55–0.99). Durability of antibody detection was dependent on antigen and immunoglobulin targets; antispike and total Ig assays demonstrated more stable longitudinal reactivity than antinucleocapsid and IgG assays. Assays with high sensitivity, specificity, and durable antibody detection are ideal for serosurveillance, but assays demonstrating waning reactivity are appropriate for other applications, including correlation with neutralizing activity and detection of anamnestic boosting by reinfections. Assay performance must be evaluated in context of intended use, particularly in the context of widespread vaccination and circulation of SARS-CoV-2 variants.

Estimated US Infection- and Vaccine-Induced SARS-CoV-2 Seroprevalence Based on Blood Donations, July 2020-May 2021

IMPORTANCE

People who have been infected with or vaccinated against SARS-CoV-2 have reduced risk of subsequent infection, but the proportion of people in the US with SARS-CoV-2 antibodies from infection or vaccination is uncertain.

OBJECTIVE

To estimate trends in SARS-CoV-2 seroprevalence related to infection and vaccination in the US population.

DESIGN, SETTING, AND PARTICIPANTS

In a repeated cross-sectional study conducted each month during July 2020 through May 2021, 17 blood collection organizations with blood donations from all 50 US states; Washington, DC; and Puerto Rico were organized into 66 study-specific regions, representing a catchment of 74% of the US population. For each study region, specimens from a median of approximately 2000 blood donors were selected and tested each month; a total of 1 594 363 specimens were initially selected and tested. The final date of blood donation collection was May 31, 2021.

EXPOSURE

Calendar time.

MAIN OUTCOMES AND MEASURES

Proportion of persons with detectable SARS-CoV-2 spike and nucleocapsid antibodies. Seroprevalence was weighted for demographic differences between the blood donor sample and general population. Infection-induced seroprevalence was defined as the prevalence of the population with both spike and nucleocapsid antibodies. Combined infection- and vaccination-induced seroprevalence was defined as the prevalence of the population with spike antibodies. The seroprevalence estimates were compared with cumulative COVID-19 case report incidence rates.

RESULTS

Among 1 443 519 specimens included, 733 052 (50.8%) were from women, 174 842 (12.1%) were from persons aged 16 to 29 years, 292 258 (20.2%) were from persons aged 65 years and older, 36 654 (2.5%) were from non-Hispanic Black persons, and 88 773 (6.1%) were from Hispanic persons. The overall infection-induced SARS-CoV-2 seroprevalence estimate increased from 3.5% (95% CI, 3.2%-3.8%) in July 2020 to 20.2% (95% CI, 19.9%-20.6%) in May 2021; the combined infection- and vaccination-induced seroprevalence estimate in May 2021 was 83.3% (95% CI, 82.9%-83.7%). By May 2021, 2.1 SARS-CoV-2 infections (95% CI, 2.0-2.1) per reported COVID-19 case were estimated to have occurred.

CONCLUSIONS AND RELEVANCE

Based on a sample of blood donations in the US from July 2020 through May 2021, vaccine- and infection-induced SARS-CoV-2 seroprevalence increased over time and varied by age, race and ethnicity, and geographic region. Despite weighting to adjust for demographic differences, these findings from a national sample of blood donors may not be representative of the entire US population.

Abstract P5-03-09: Phenotypic modulation of mammary stem cells by CAPE (caffeic acid phenethyl ester)

Background: Over 30% of cancer patients and up to 60% of breast cancer patients routinely use alternative formulations, commonly in combination with allopathic treatment, which may be linked with fewer adverse events. The naturopathic formulation propolis, and its active component Caffeic Acid Phenethyl Ester (CAPE), is a widely available honeybee product with an extended safety history credited with anti-inflammatory, antioxidant, and antitumor properties. We have previously shown that CAPE, inhibits growth of MCF-7 (ER+/PR+) and MDA-231 (TNBC) cells by cell cycle arrest and apoptosis; inhibits mdr-1 gene expression, NF-kB, and VEGF (1). In addition, CAPE inhibits the growth and tumorigenic potential of breast cancer stem cells derived from MDA-231 cells (2). We have demonstrated that CAPE, which is structurally similar to the hydroxamic acid class of HDAC inhibitors, mediates its effects on breast cancer through epigenetic modifications via histone deacetylase inhibition (unpublished data). We hypothesized that CAPE would inhibit mammary stem cells, which was tested in primary mouse mammary epithelial cells and a human breast epithelial cell line.

Materials and Methods: Single mammary epithelial cells were isolated from Balb/c mice and cultured for 8 days in Ultra Low Attachment 96 well plates using mammosphere media containing 5%FBS and 5% Matrigel (3). The first generation of mammospheres were dissociated into single cells and recultured in the presence of CAPE for 8 days in secondary and tertiary passages. Alternatively, a Let7c-miRNA reporter expressed in MCF10a non-malignant human mammary epithelial cells were sorted to isolate Let7c-negative cells and placed in mammosphere culture and similarly treated with CAPE for 7 to 10 days. The mammospheres were stained with luminal marker K18 and basal marker K14 and examined using immunofluorescent microscopy.

Results: CAPE treatment results in a dose dependent decrease in mammosphere forming efficiency (MFE) of mammospheres obtained from a primary culture of mammary gland derived epithelial cells as well as those derived from the MCF10A cell line. Furthermore, MFE of tertiary cultures is reduced even after CAPE is removed. Interestingly, mammospheres shifted from predominantly K14 to K18 positive in those mammospheres that formed at the lowest CAPE treatment concentration.

Conclusion: CAPE inhibits mammosphere formation from normal mouse mammary gland and from a non-malignant human mammary cell line. The mechanism of CAPE effects may lie in its established role in inducing cell cycle arrest, apoptosis or via epigenetic mechanisms, among others. Interestingly, CAPE causes a shift from a basal to a luminal cell phenotype in mammospheres, suggesting an effect on lineage commitment.

References

1) *Wu J, *Omene C, Karkaszka J, et al. CANCER LETTERS. 2011 Sep 1;308(1):43-53. Epub 2011 May 13. (* Share 1st authorship)

2) Omene C, Wu J, Frenkel K. INVESTIGATIONAL NEW DRUGS. 2012 Aug;30(4):1279-88. Epub 2011 May 3.

3) Guo W, Keckesova Z, Donaher JL, et al. CELL. 2012 Mar 2;148(5):1015-28.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P5-03-09.

Paediatric ventricular assist devices: current achievements

In chronic cardiomyopathy, mechanical circulatory support plays an increasingly important role for children as the shortage of suitable donor hearts increases times on the transplant waiting list. Ventricular assist devices (VADs) for adults have evolved dramatically over the last decade, both as a bridge to transplantation and for permanent support. In contrast, VADs designed for children, especially for all age groups, are still in their infancy. The Medos HIA and the Berlin Heart Excor are specially designed for children with a body surface area <1.2 m2. Increased experience with existing paediatric VADs and the introduction of third-generation VADs for the paediatric age group offer new possibilities for children suffering from end-stage heart failure. We review the literature on this topic, summarise the indications and contraindications for long-term support VADs and describe the decision-making algorithm used at our institution for use of long-term VADs in children.

Abnormal interhemispheric connectivity in neonates with D-transposition of the great arteries undergoing cardiopulmonary bypass surgery

BACKGROUND AND PURPOSE

Neonates with severe CHD require CPB within the first days of life. White matter injury can occur before surgery, and this may impair the long-term neurodevelopmental and psychosocial outcome. The purpose of this study was to assess the microstructural development of the CC in infants with CHD before and after CPB for transposition of the great arteries.

MATERIALS AND METHODS

Fifteen patients with CHD and 11 age-matched HC were recruited. We separately quantified the parallel (E1) and perpendicular (E23) diffusions, the ADC, and FA of the genu of the CC and splenium of the CC before and after surgery.

RESULTS

In presurgical measures of the genu of the CC, higher E23 (P = .018), higher ADC (P = .026), and lower FA (P = .033) values were measured compared with those in HC. In the postsurgery scans, the genu of the CC had higher E23 (P = .013), higher ADC (P = .012), and lower FA (P = .033) values compared with those in HC. There was no significant difference in any DTI indices between the pre- and postsurgical groups.

CONCLUSIONS

We report abnormal microstructural development in the genu of the CC of infants with d-TGA before and after CPB. High E23, high ADC, and low FA values in the genu of the CC may be explained by abnormal axonal pruning, thinner myelin sheaths, smaller axonal diameters, or more oligodendrocytes. It appears that the genu of the CC is more vulnerable than the splenium of the CC in patients with CHD and may serve as a biomarker to identify infants at highest risk for adverse neurodevelopmental outcome.

Early results of balloon dilatation of the stenotic bovine jugular vein graft in the right ventricular outflow tract in children

The aim of this study was to evaluate the early results of interventional balloon dilatation of stenotic bovine jugular vein (BJV) grafts implanted for reconstruction of the right ventricular outflow tract (RVOT) in children.

METHODS

From May 2001 to December 2005, 153 BJV grafts were implanted in children in our institution. An average of 16.9 (7.6-41.1) months after implantation, 17 balloon dilatations in a significant stenosis proximal (n = 1), distal anastomosis (n = 8), BJV valve (n = 3), or at multiple sites (n = 5) were performed in 15 children (male:female = 9:6) with a mean age of 3.9 (0.8-13.0) years. Balloon diameter was 75-133.3% (mean 100.3) of the original BJV size. Mean follow-up was 8.8 (2 days to 22.8 months) months.

RESULTS

In 10 interventions (58.8%) the instantaneous peak gradient was reduced below 50 mmHg. A balloon diameter > or =100% of the original BJV size correlated significantly with a successful intervention. No major complications, two minor (nonobstructive floating membranes at the dilatation site and one septicemia) occurred afterward. Freedom from reintervention after 6 months was 58.2% for all, 77.8% for dilatations of the proximal anastomosis and mixed stenotic lesions, and 33.3% for the distal anastomosis.

CONCLUSION

Balloon dilatation of stenotic BJV grafts is safe and can significantly reduce the pressure gradient in two-thirds of interventions. Balloon diameters above the original graft size should be aimed for. The most frequent stenosis of the distal anastomosis tends to renarrow early after dilatation. Nevertheless, balloon dilatation should be considered in nearly every stenotic graft to gain time until a surgical or interventional graft exchange.

Low cell pH depresses peak power in rat skeletal muscle fibres at both 30 degrees C and 15 degrees C: implications for muscle fatigue

Historically, an increase in intracellular H(+) (decrease in cell pH) was thought to contribute to muscle fatigue by direct inhibition of the cross-bridge leading to a reduction in velocity and force. More recently, due to the observation that the effects were less at temperatures closer to those observed in vivo, the importance of H(+) as a fatigue agent has been questioned. The purpose of this work was to re-evaluate the role of H(+) in muscle fatigue by studying the effect of low pH (6.2) on force, velocity and peak power in rat fast- and slow-twitch muscle fibres at 15 degrees C and 30 degrees C. Skinned fast type IIa and slow type I fibres were prepared from the gastrocnemius and soleus, respectively, mounted between a force transducer and position motor, and studied at 15 degrees C and 30 degrees C and pH 7.0 and 6.2, and fibre force (P(0)), unloaded shortening velocity (V(0)), force-velocity, and force-power relationships determined. Consistent with previous observations, low pH depressed the P(0) of both fast and slow fibres, less at 30 degrees C (4-12%) than at 15 degrees C (30%). However, the low pH-induced depressions in slow type I fibre V(0) and peak power were both significantly greater at 30 degrees C (25% versus 9% for V(0) and 34% versus 17% for peak power). For the fast type IIa fibre type, the inhibitory effect of low pH on V(0) was unaltered by temperature, while for peak power the inhibition was reduced at 30 degrees C (37% versus 18%). The curvature of the force-velocity relationship was temperature sensitive, and showed a higher a/P(0) ratio (less curvature) at 30 degrees C. Importantly, at 30 degrees C low pH significantly depressed the ratio of the slow type I fibre, leading to less force and velocity at peak power. These data demonstrate that the direct effect of low pH on peak power in both slow- and fast-twitch fibres at near-in vivo temperatures (30 degrees C) is greater than would be predicted based on changes in P(0), and that the fatigue-inducing effects of low pH on cross-bridge function are still substantial and important at temperatures approaching those observed in vivo.

Automatic segmentation of pancreatic images using ISODATA alorithm

14149

Background: Pancreatic cancer is the second most common gastrointestinal malignancy in the United States, where it ranks 4th among all deaths caused by cancers. Early detection of pancreatic cancer remains a challange. Methods: MR images with different T1 and T2 weighting from the anatomical regions with the same imaging parameters were obtained. ISODATA segmentation algorithm, a multivariate method was used to reliable detect the various clusters in the data sets. Results: In all the four subjects, the pancreatic region was found to be from a different (and unique) cluster. This cluster covered the pancreatic region in all the four subjects. Conclusions: The ISODATA algorithm presented could detect the pancreatic region without manual tracing.

No significant financial relationships to disclose.

Hornhaut-Pachymetrie und Augeninnendruck

Just recently studies on glaucoma have emphasised the significance of intraocular pressure in the diagnosis of glaucoma and the importance of intraocular pressure reduction in the management of glaucoma. Central corneal thickness appears to play an important role in the exact measurement of intraocular pressure and in the diagnostic assessment of glaucoma. Numerous studies have verified that corneal thickness shows systematic differences in different forms of glaucoma. Since deviations of corneal thickness from normal can possibly result in an artificial change of Goldmann applanation values, it would be a most important source of error in the diagnosis of glaucoma to ignore central corneal thickness. Corrections of intraocular pressure measured with applanation tonometry can be achieved in various ways but there is considerable divergence in the results. The absence of a generally accepted algorithm for the correction of intraocular pressure measured with applanation tonometry should not prevent us from a wide application of pachymetry, since it delivers valuable additional information on the individual risk of glaucoma.

Hornhautdickenmessung bei Glaukompatienten

BACKGROUND

For the past 5 decades, Goldmann's applanation tonometry has been the basis for measurement of intraocular pressure. In this process, it is assumed that the corneal architecture-and particularly corneal thickness-does not have significant influence on the applanation tonometry. The aim of this study was to assess central corneal thickness in patients with primary open angle glaucoma (POWG), normal tension glaucoma (NDG), and ocular hypertension (OHT) compared to the central corneal thickness of control subjects.

METHOD

In 200 consecutive glaucoma patients corneal pachymetry was performed with the Orbscan II system and a pachymetry map was obtained. Simultaneously, corneal pachymetry was also performed in 200 age- and sex-matched control subjects. To avoid diurnal variations the pachymetry measurements were performed at the same time of the day.

RESULTS

The central corneal thickness (CCT) distribution turned out to be a near-Gaussian curve in patients with glaucoma and in the control subjects. The mean CCT in glaucoma patients was 561+/-49.4 micro m with a minimum of 448 micro m and a maximum of 732 micro m. In control subjects the mean CCT was 555.9+/-34.6 micro m with a minimum of 480 micro m and a maximum of 635 micro m. Further evaluation of CCT of glaucoma patients demonstrated that the CCT in patients with POWG was 559.5+/-43.5 micro m, in patients with NDG was 530.3+/-51.1 micro m and with OHT was 624.2+/-25.4 micro m.

CONCLUSIONS

Central corneal thickness in patients with OHT was significantly greater, and in patients with NDG significantly lower, compared to control subjects. In defining the desired intraocular pressure in glaucoma patients, in the future CCT measurements should be considered along with intraocular pressure measurement and visual field analysis.

Fiber type and temperature dependence of inorganic phosphate: implications for fatigue

Elevated levels of P(i) are thought to cause a substantial proportion of the loss in muscular force and power output during fatigue from intense contractile activity. However, support for this hypothesis is based, in part, on data from skinned single fibers obtained at low temperatures (< or =15 degrees C). The effect of high (30 mM) P(i) concentration on the contractile function of chemically skinned single fibers was examined at both low (15 degrees C) and high (30 degrees C) temperatures using fibers isolated from rat soleus (type I fibers) and gastrocnemius (type II fibers) muscles. Elevating P(i) from 0 to 30 mM at saturating free Ca(2+) levels depressed maximum isometric force (P(o)) by 54% at 15 degrees C and by 19% at 30 degrees C (P < 0.05; significant interaction) in type I fibers. Similarly, the P(o) of type II fibers was significantly more sensitive to high levels of P(i) at the lower (50% decrease) vs. higher temperature (5% decrease). The maximal shortening velocity of both type I and type II fibers was not significantly affected by elevated P(i) at either temperature. However, peak fiber power was depressed by 49% at 15 degrees C but by only 16% at 30 degrees C in type I fibers. Similarly, in type II fibers, peak power was depressed by 40 and 18% at 15 and 30 degrees C, respectively. These data suggest that near physiological temperatures and at saturating levels of intracellular Ca(2+), elevated levels of P(i) contribute less to fatigue than might be inferred from data obtained at lower temperatures.

Transitional cell carcinoma arising within a paratubal cyst: report of a case

We report the clinical and morphologic features of a transitional cell carcinoma (TCC) that arose within a paratubal cyst of the right broad ligament. This case represents only the second report of a TCC arising in the broad ligament and the first with documented origin within a paratubal cyst. A possible explanation for this tumor's histogenesis as it relates to the more common transitional cell neoplasms of the ovary is presented.

Toxic megacolon in cytomegalovirus colitis

We report a case of toxic megacolon manifesting in cytomegalovirus (CMV) colitis in a 55-yr-old man with steroid-dependent chronic obstructive pulmonary disease. He presented to the hospital with increasing dyspnea and low-grade fever. His hospital course was characterized by the poor response of his symptoms to treatment, and by the subsequent development of intermittent hematochezia and, eventually, acute abdomen. The surgical specimen showed dilatation of the cecum and ascending colon with a solitary mucosal ulcer in the latter. The major histologic changes were limited to the area of ulceration. In addition to classical CMV inclusions. vasculitis manifested in two forms, namely, leukocytoclastic type and fibrinoid necrosis. The patient died shortly thereafter, due to multi-organ system failure. To our knowledge, this represents the first reported case of toxic megacolon due to CMV infection without underlying inflammatory bowel disease. The pathogenesis of toxic colonic dilatation remains unknown.

Meckel syndrome with polysplenia: case report and review of the literature

A 19-week gestation female fetus had multiple anomalies suggesting Meckel syndrome with polysplenia. In over 200 reported cases of Meckel syndrome, only 2 similar cases are documented. Both were male infants, one with bilateral left-sidedness (polysplenia), the other with bilateral right-sidedness (M-anisosplenia). Meckel syndrome is a complex MCA (multiple congenital anomaly) syndrome. Thus, the finding of polysplenia is to be interpreted as another such midline anomaly, rather than as a causally independent malformation.

Adenocarcinoma in situ of the cervix. Clinicopathologic observations of 11 cases

Adenocarcinomas in situ (AIS) of the cervix represent less than 1% of all primary adenocarcinomas of the cervix; 11 cases from the Magee-Women's Hospital (1969-1984) are described. The patients' ages ranged from 25 to 81 years (average 48.5 years). One patient was nulliparous and the others had one to five children. The most common presenting symptom was postmenopausal or other abnormal vaginal bleeding. The AIS were diagnosed as follows: a positive, suspicious, or dysplastic Pap smear in seven cases; in three, the AIS was an incidental finding during a hysterectomy; and one case was diagnosed in an endocervical curettage. Most of the AIS were in or near the transformation zone, having two distinct histologic glandular patterns with tall columnar or large ballooned cells (Types I and II respectively). In three cases an associated in situ squamous cell carcinoma or severe dysplasia of the cervix was seen. Two patients had associated well-differentiated adenocarcinoma of the endometrium and a third had endometrial hyperplasia. One lesion stained strongly positive for carcinoembryonic antigen and all others were negative. Eight patients underwent total abdominal hysterectomy and bilateral salpingo-oopherectomy (TAH-BSO), two had total abdominal hysterectomy (one with salpingo-oophorectomy), and one 25-year-old was treated by deep conization only. All patients, except one who died with associated adenocarcinoma of the cecum, were alive 8 to 127 months after treatment.

Transforming growth factors induce markers of neoplasia in cultured adult rat bladder

Transforming growth factors alpha and beta (TGF-alpha and TGF-beta) isolated from normal mouse kidney induced gross morphological changes in rat urothelial cells maintained in organ culture. These morphological effects are similar to those observed after long-term treatment of rat bladder organ cultures with the carcinogen N-methyl-N-nitrosourea (MNU) or the promoting agents sodium saccharin and sodium cyclamate. Cultures were treated continuously with 5-25 micrograms/ml of Bio-Gel P-30-purified TGF containing both TGF-alpha and TGF-beta between days 1 and 14 in culture, or with 5 micrograms/ml from days 28 to 42. Controls received 1-10 ng/ml epidermal growth factor (EGF) or control medium. Untreated controls retained a normal urothelium throughout the period of study. Mature superficial-type cells covered most of the surface and less mature forms appeared on the cut sides and damaged areas where cells followed the normal pattern of urothelial differentiation. EGF at 5 and 10 ng/ml caused necrosis of the entire urothelium but at 1 and 2 ng/ml had minimal effects on histology and scanning electron microscopical appearance up to 14 days in culture. Crude P-30-purified TGFs induced a series of dose-related changes from 4 days, which were maximal at 8 days and persisted or decreased between 8 and 14 days. These included hyperplasia, loss of epithelial polarity, hyperchromasia and elongation of basal cells between the overlying cell layers to reach the culture surface. Scanning electron microscopy showed the appearance at the culture surface of immature cells with gross surface abnormalities including large numbers of blebs, stubby microvilli and long pleomorphic microvilli. Immature cells on the sides of the culture and in damaged areas developed similar features. At crude TGF doses of 10 micrograms/ml many superficial cells were rounded, some became cystic and epithelial necrosis was observed. Cultures treated with h.p.l.c.-purified TGF-beta at 80 ng/ml in the presence of 2 ng/ml EGF showed similar effects to those treated with 5 micrograms/ml P-30-purified TGF. Fully differentiated cultures treated from 28 to 42 days with crude TGF, showed changes similar to those seen in early cultures. However, histological changes, particularly basal cell elongation were more widespread and there was an abnormal development of globular processes between the membrane ridges of mature superficial cells. Neither crude TGF nor EGF stimulated growth in soft agar of isolated epithelial cells from freshly killed rats or organ cultures pretreated for 7 days with EGF or TGF.(ABSTRACT TRUNCATED AT 400 WORDS)

Suppression of the transformed phenotype in somatic cell hybrids

Somatic cell hybrids between mouse mammary tumour cells (TA3B) and diploid rat embryo fibroblasts (REF) or between TA3B and Syrian hamster sarcoma cells (BI) were examined for the in vitro characteristics of transformed cells as soon as possible after cell fusion. Unlike the parental tumour cells as three of four TA3B X REF and five BI X TA3B independent hybrid lines had low colony-forming efficiencies in agar, exhibited density-dependent inhibition of growth and did not form colonies on confluent monolayers of 3T3 cells, demonstrating that the transformed phenotype was suppressed in these hybrids. In addition tests of some of the hybrid lines for tumour production in nude mice showed that this was also suppressed. Suppression was more stable in the TA3B X REF than in the BI X TA3B hybrids, variants of the BI X TA3B hybrids with the properties of transformed cells could be readily isolated by subculturing cells that had grown in agar. Tumour growth selected for hybrids with the characteristics of transformed cells, and derivatives of the hybrids selected to show the transformed phenotype readily produced tumours. These correlations suggest that the transformed phenotype and malignancy may be under the same control in these cells. The phenomenon of suppression may be explained by the hypothesis that neoplastic transformation results from recessive mutations in genes which control the normal phenotype. On this model the finding of suppression in hybrids between two different tumour lines is interpreted as complementation and indicates that the mutations are not the same in all cell lines.