Early empiric antibiotic use in COVID-19 patients: results from the international VIRUS registry

OBJECTIVES

COVID-19 escalated inappropriate antibiotic use. We determined the distribution of pathogens causing community-acquired co-infections, the rate, and factors associated with early empiric antibiotic (EEAB) treatment among hospitalized COVID-19 patients.

METHODS

The Society of Critical Care Medicine Discovery Viral Infection and Respiratory Illness Universal Study (VIRUS) COVID-19 Registry including 68,428 patients from 28 countries enrolled between January 2020 and October 2021 were screened. After exclusions, 7830 patients were included in the analysis. Azithromycin and/or other antibiotic treatment given within the first 3 days of hospitalization was investigated. Univariate and multivariate analyses were performed to determine factors associated with EEAB use.

RESULTS

The majority (6214, 79.4%) of patients received EEAB, with azithromycin combination being the most frequent (3146, 40.2%). As the pandemic advanced, the proportion of patients receiving EEAB regressed from 84.4% (786/931) in January-March 2020 to 65.2% (30/46) in April-June 2021 (P < 0.001). Beta-lactams, especially ceftriaxone was the most commonly used antibiotic. Staphylococcus aureus was the most commonly isolated pathogen. Multivariate analysis showed geographical location and pandemic timeline as the strongest independent predictors of EEAB use.

CONCLUSIONS

EEAB administration decreased as pandemic advanced, which may be the result of intensified antimicrobial stewardship efforts. Our study provides worldwide goals for antimicrobial stewardship programs in the post-COVID-19 era.

Association of Early Steroid Administration With Outcomes of Children Hospitalized for COVID-19 Without Multisystem Inflammatory Syndrome in Children

Importance

There is limited evidence for therapeutic options for pediatric COVID-19 outside of multisystem inflammatory syndrome in children (MIS-C).

Objective

To determine whether the use of steroids within 2 days of admission for non-MIS-C COVID-19 in children is associated with hospital length of stay (LOS). The secondary objective was to determine their association with intensive care unit (ICU) LOS, inflammation, and fever defervescence.

Design, Setting, and Participants

This cohort study analyzed data retrospectively for children (<18 years) who required hospitalization for non-MIS-C COVID-19. Data from March 2020 through September 2021 were provided by 58 hospitals in 7 countries who participate in the Society of Critical Care Medicine Discovery Viral Infection and Respiratory Illness Universal Study (VIRUS) COVID-19 registry.

Exposure

Administration of steroids within 2 days of admission.

Main Outcomes and Measures

Length of stay in the hospital and ICU. Adjustment for confounders was done by mixed linear regression and propensity score matching.

Results

A total of 1163 patients met inclusion criteria and had a median (IQR) age of 7 years (0.9-14.3). Almost half of all patients (601/1163, 51.7%) were male, 33.8% (392/1163) were non-Hispanic White, and 27.9% (324/1163) were Hispanic. Of the study population, 184 patients (15.8%) received steroids within 2 days of admission, and 979 (84.2%) did not receive steroids within the first 2 days. Among 1163 patients, 658 (56.5%) required respiratory support during hospitalization. Overall, patients in the steroids group were older and had greater severity of illness, and a larger proportion required respiratory and vasoactive support. On multivariable linear regression, after controlling for treatment with remdesivir within 2 days, country, race and ethnicity, obesity and comorbidity, number of abnormal inflammatory mediators, age, bacterial or viral coinfection, and disease severity according to ICU admission within first 2 days or World Health Organization ordinal scale of 4 or higher on admission, with a random intercept for the site, early steroid treatment was not significantly associated with hospital LOS (exponentiated coefficient, 0.94; 95% CI, 0.81-1.09; P = .42). Separate analyses for patients with an LOS of 2 days or longer (n = 729), those receiving respiratory support at admission (n = 286), and propensity score-matched patients also showed no significant association between steroids and LOS. Early steroid treatment was not associated with ICU LOS, fever defervescence by day 3, or normalization of inflammatory mediators.

Conclusions and Relevance

Steroid treatment within 2 days of hospital admission in a heterogeneous cohort of pediatric patients hospitalized for COVID-19 without MIS-C did not have a statistically significant association with hospital LOS.

TRIP12 as a mediator of human papillomavirus/p16-related radiation enhancement effects

Patients with human papillomavirus (HPV)-positive head and neck squamous cell carcinoma (HNSCC) have better responses to radiotherapy and higher overall survival rates than do patients with HPV-negative HNSCC, but the mechanisms underlying this phenomenon are unknown. p16 is used as a surrogate marker for HPV infection. Our goal was to examine the role of p16 in HPV-related favorable treatment outcomes and to investigate the mechanisms by which p16 may regulate radiosensitivity. HNSCC cells and xenografts (HPV/p16-positive and -negative) were used. p16-overexpressing and small hairpin RNA-knockdown cells were generated, and the effect of p16 on radiosensitivity was determined by clonogenic cell survival and tumor growth delay assays. DNA double-strand breaks (DSBs) were assessed by immunofluorescence analysis of 53BP1 foci; DSB levels were determined by neutral comet assay; western blotting was used to evaluate protein changes; changes in protein half-life were tested with a cycloheximide assay; gene expression was examined by real-time polymerase chain reaction; and data from The Cancer Genome Atlas HNSCC project were analyzed. p16 overexpression led to downregulation of TRIP12, which in turn led to increased RNF168 levels, repressed DNA damage repair (DDR), increased 53BP1 foci and enhanced radioresponsiveness. Inhibition of TRIP12 expression further led to radiosensitization, and overexpression of TRIP12 was associated with poor survival in patients with HPV-positive HNSCC. These findings reveal that p16 participates in radiosensitization through influencing DDR and support the rationale of blocking TRIP12 to improve radiotherapy outcomes.

Pompe's Disease in Childhood: A Metabolic Myopathy

BACKGROUND

Myopathy of metabolic origin in childhood occurs due to a variety of conditions. Pompe's Disease also known as Glycogen storage disease Type II, is a rare storage disorder with clinical presentation akin to spinal muscular atrophy.

METHODS

A series of patients with suspected metabolic myopathy were reviewed at a tertiary care service hospital over a period of three years. The diagnosis was confirmed by estimation of acid alpha glucosidase activity.

RESULT

At our centre, these cases presented with generalized hypotonia, organomegaly (hepatomegaly, cardiomegaly) and congestive cardiac failure. Infantile onset, the most severe form of Pompe's disease, was the commonest form accounting for 75% of the cases. Four of the babies with infantile onset Pompe's disease expired, three due to refractory heart failure and one to fulminant respiratory infection before 15 months of age.

CONCLUSION

Pompe's Disease is now being increasingly diagnosed, due to definitive enzyme estimation facilities. With the recent availability of enzyme replacement therapy with Myozyme, the prognosis is likely to change for the better.

Meconium Aspiration Syndrome: An Insight

Meconium aspiration syndrome (MAS) is respiratory distress in a newborn baby caused by the presence of meconium in the tracheobronchial airways. The aspiration of meconium stained amniotic fluid by the fetus can happen during antepartum or intrapartum periods and can result in airway obstruction, interference with alveolar gas exchange, chemical pneumonitis as well as surfactant dysfunction. These pulmonary effects cause gross ventilation-perfusion mismatching. To complicate matters further, many infants with MAS have primary or secondary persistent pulmonary hypertension of the newborn as a result of chronic in utero stress and thickening of the pulmonary vessels. Although meconium is sterile, its presence in the air passages can predispose the infant to pulmonary infection. MAS is essentially a clinical diagnosis and should always be suspected in a child with respiratory distress and meconium-stained amniotic fluid at delivery. Though a known entity for a long time, its management still remains contentious. Intubation and direct tracheal suction is performed when meconium is observed in the amniotic fluid and the infant is not vigorous. Subsequent management involves ventilation, surfactant instillation and lavage, inhaled nitric oxide and high frequency ventilation. The role of steroids continues to be controversial.

Release of oncofetal fibronectin from human placenta

Oncofetal fibronectin (onfFN) is an extracellular matrix (ECM) protein synthesized by tumours and fetal tissue including placenta. The appearance of onfFN and other cellular FNs in cervico-vaginal secretions and maternal blood is associated with adverse pregnancy outcomes. In the current study, we used dual (maternal and fetal) perfusion of human term placentae and primary cultures of syncytiotrophoblasts (SCTs) to determine whether the human placenta releases onfFN. ELISA and Western blotting revealed that onfFN is preferentially released to the maternal perfusate in a time-dependent manner. Immunodetection with FDC-6, extra domain A (EDA) and cell binding domain-specific antibodies revealed onfFN in maternal perfusate to be a high molecular weight (>450 kDa) protein dimer, similar to that found in amniotic fluid. This suggested that onfFN was released intact from placenta and not cleaved from an ECM. In addition, a similar high molecular weight dimeric onfFN species was noted in conditioned media from cultures of SCTs. Since SCTs directly release proteins to the intervillous space, this suggests that SCTs may be a source of onfFN detected in maternal perfusate. These results indicate that onfFN is released from human placenta and thus levels in maternal sera may provide insight into placental pathophysiology.

Maternal smoking and the risk of congenital birth defects: a cohort study

BACKGROUND

The literature linking gestational smoking to congenital defects has been very inconsistent. The purpose of this study was to reinvestigate the relation between gestational smoking and congenital malformations.

METHODS

This study was a retrospective cohort (N = 18,016) of live births in the TriHealth Hospital system from 1 January 1998 to 31 December 1999. The cohort included 1,943 mothers who were smokers. Congenital defects were grouped into 22 different categories. Multifactorial logistic regression was used to find any association between exposure and the possible outcomes.

RESULTS

Mothers who smoked were significantly younger and had babies of lower birth weight and shorter gestational age (P < .05). Of the 22 categories of congenital defects, only cardiovascular system abnormalities showed a significant difference (P < .01) between the two groups. The remaining 21 categories of congenital defects showed no statistical difference.

CONCLUSION

Women who smoke during pregnancy have infants that are significantly smaller and of shorter gestational age compared with mothers who do not smoke. Based on these data and findings from most of the available literature, however, gestational smoking is unlikely to cause a large increase in congenital birth defects.

Postmenopausal endogenous oestrogens and risk of endometrial cancer: results of a prospective study

We assessed the association of postmenopausal serum levels of oestrogens and sex hormone-binding globulin (SHBG) with endometrial cancer risk in a case-control study nested within the NYU Women's Health Study cohort. Among 7054 women postmenopausal at enrolment, 57 cases of endometrial cancer were diagnosed a median of 5.5 years after blood donation. Each case was compared to 4 controls matched on age, menopausal status at enrolment, and serum storage duration. Endometrial cancer risk increased with higher levels of oestradiol (odds ratio = 2.4 in highest vs lowest tertile, P for trend = 0.02), percent free oestradiol (OR = 3.5, P< 0.001), and oestrone (OR = 3.9, P< 0.001). Risk decreased with higher levels of percent SHBG-bound oestradiol (OR = 0.43, P = 0.03) and SHBG (OR = 0.39, P = 0.01). Trends remained in the same directions after adjusting for height and body mass index. A positive association of body mass index with risk was substantially reduced after adjusting for oestrone level. Our results indicate that risk of endometrial cancer increases with increasing postmenopausal oestrogen levels but do not provide strong support for a role of body mass index independent of its effect on oestrogen levels.

Estrone and estradiol metabolism in vivo in human breast cysts

Fibrocystic disease of the breast manifesting palpable cysts express breast cyst fluids frequently containing estrogen sulfates at concentrations far exceeding those found in sera of the patient. The study explored the potential of the breast cyst to synthesize some of these estrogen sulfates. Deuterated estrone and estradiol were synthesized and either (estradiol, 4 cases or estrone, 2 cases) was injected into a cyst. The cyst was aspirated at approximately 0, 4 and 8 h, the target being 1 ml, 50% and complete aspiration respectively. Metabolites were purified sequentially by ether extraction, enzymatic hydrolysis of estrogen conjugates, chromatography on Sephadex LH 20 and identified by gas chromatography linked to mass spectrometry. The unconjugated fraction isolated from the ether extract was subjected to the same purification and detection scheme. Among the conjugates, deuterated estrone sulfate was the major metabolite of either precursor in all studies, while estradiol sulfate was not detected in any of the 6 experiments. The sulfate fractions also yielded traces of 16alpha-hydroxyestrone (2 studies), 4-hydroxyestrone (4 studies) and 2-hydroxyestrone (1 study). In the unconjugated fraction, one study with deuterated estradiol, 4- hydroxyestrone was obtained. In one study with deuterated estrone, traces of 2-hydroxyestrone and 16alpha- hydroxyestrone were obtained. These novel data are significant because patients with fibrocystic disease are at slightly elevated risk for developing breast cancer and 16alpha-hydroxyestrone and 4- hydroxyestrone are reported carcinogens.

Radiation-induced transcription factor activation in the rat cerebral cortex

PURPOSE

To determine the effects of ionising radiation on the DNA-binding activity of the injury-related transcription factors AP-1, Sp-1, p53 and NFkappaB in the rat brain.

MATERIALS AND METHODS

Male Sprague-Dawley rats were irradiated with 137Cs gamma-rays at 3.8Gy/min and the cerebral cortex was isolated at intervals up to 24h. Nuclear protein extract of the cerebral cortex was analysed by electrophoretic mobility shift assay for DNA-binding activity of AP-1, Sp-1, p53 and NFkappaB. In addition, total RNA was extracted from the cerebral cortex and subjected to northern analysis.

RESULTS

The DNA-binding activity of each of the transcription factors increased in a time- and dose-dependent manner after irradiation. Maximum increase in the activity of AP-1, Sp-1, and p53 DNA binding was seen after exposure to 10Gy and then decreased after higher doses. In contrast, NFkappaB DNA-binding activity continued to increase out to at least 30Gy. The levels of bFGF and p21WAF-1 mRNA increased after irradiation, suggesting an increase in the transactivating activity of AP-1, Sp-1, and p53.

CONCLUSIONS

These data indicate that the response of the CNS to irradiation includes the activation of a similar set of transcription factors as previously observed after other types of insults.

Serum estradiol-binding profiles in postmenopausal women undergoing three common estrogen replacement therapies: associations with sex hormone-binding globulin, estradiol, and estrone levels

OBJECTIVE

To compare the effects of three commonly prescribed estrogen replacement therapies-oral conjugated equine estrogens (CEE; n = 37), oral micronized estradiol (ME; n = 25), and transdermal estradiol (TE; n = 24)-on the binding characteristics of plasma estradiol as related to the concentrations of blood sex hormone-binding globulin (SHBG), estradiol, and estrone.

DESIGN

Menopausal volunteers, opting for estrogen replacement therapy, gave blood at 0, 2, and 4 months. SHBG was assayed by automated immunoabsorbent technology. Estradiol and estrone were determined by quantitative gas chromatography/mass spectrometry. After tritiated estradiol was added to serum, the percentage of estradiol not bound to protein was determined by ultrafiltration and the percentage of estradiol bound to SHBG was measured by a method exploiting that this protein, even when bound to estradiol, binds avidly to Concanavalin A-Agarose.

RESULTS

In each study, 2- and 4-month data were similar. Increases in SHBG concentrations were 100% (p < 0.001), 45% (p < 0.001), and 12% (nonsignificant) for subjects who were receiving CEE, ME, and TE regimens, respectively. Decreases in the percentage of estradiol not bound to protein and increases in the percentage of estradiol bound to SHBG correlated with changes in the concentrations of this protein mediated by the therapies. The order for increases in estradiol was ME-TE >> CEE, whereas for estrone, the order was ME > CEE >> TE, divergent from the SHBG responses.

CONCLUSIONS

The diverse responses observed can be explained by differences in the estrogen load delivered to target tissues as controlled by the intermediary circulation and metabolism of the hormones introduced in these regimens.

Race and differences in breast cancer survival in a managed care population

BACKGROUND

African-American women with breast cancer have poorer survival than European-American women. After adjustment for socioeconomic variables, survival differences diminish but do not disappear, possibly because of residual differences in health care access, biology, or behavior. This study compared breast cancer survival in African-American and European-American women with similar health care access.

METHODS

We measured survival in women with breast cancer who are served by a large medical group and a metropolitan Detroit health maintenance organization where screening, diagnosis, treatment, and follow-up are based on standard practices and mammography is a covered benefit. We abstracted data on African-American and European-American women who had been diagnosed with breast cancer from January 1986 through April 1996 (n = 886) and followed these women for survival through April 1997 (137 deaths).

RESULTS

African-American women were diagnosed at a later stage than were European-American women. Median follow-up was 50 months. Five-year survival was 77% for African-American and 84% for European-American women. The crude hazard ratio for African-American women relative to European-American women was 1.6 (95% confidence interval [CI] = 1.1-2.2). Adjusting only for stage, the hazard ratio was 1.3 (95% CI = 0.9-1.9). Adjusting only for sociodemographic factors (age, marital status, and income), the hazard ratio was 1.2 (95% CI = 0.8-1.9). After adjusting for age, marital status, income, and stage, the hazard ratio was 1.0 (95% CI = 0.7-1.5).

CONCLUSION

Among women with similar medical care access since before their diagnoses, we found ethnic differences in stage of breast cancer at diagnosis. Adjustment for this difference and for income, age, and marital status resulted in a negligible effect of race on survival.

NF kappa B activity and target gene expression in the rat brain after one and two exposures to ionizing radiation

The central nervous system injury that can result after radiotherapy has been suggested to involve induced gene expression and cytokine production. We have previously shown that irradiation of primary cultures of rat astrocytes results in the activation of NF kappa B. To determine whether such an effect also occurs in vivo, NF kappa B activity was analyzed in the cerebral cortex of the rat brain after whole body irradiation. After a single dose of 15 Gy, NF kappa B activity was increased by 2 h postirradiation, returning to unirradiated levels by 8 hours. The increase was dose-dependent beginning at 2 Gy and continuing to at least 22.5 Gy. NF kappa B activity in the irradiated cortex was not accompanied by I kappa B alpha degradation. When 7.5 Gy was delivered 24 h before the 15 Gy, the increase in NF kappa B activity after 15 Gy was significantly reduced. These results suggest that an initial exposure to radiation induced a refractory period in the brain during which the susceptibility of NF kappa B to activation by subsequent irradiation was significantly reduced. This period of reduced sensitivity to radiation was also apparent for the induction of the NF kappa B-regulated cytokines IL-1 beta, IL-6, and TNF alpha.

X-irradiation-induced loss of O-2A progenitor cells in rat spinal cord is inhibited by implants of cells engineered to secrete glial growth factor 2

The loss of O-2A progenitor cells has been implicated as a critical event in radiation-induced spinal cord demyelination. To investigate whether glial growth factor 2 (GGF2) affects the number of O-2A cells in the irradiated rat cervical spinal cord, an ex vivo gene therapy approach was applied in which CHO cells engineered to express recombinant human GGF2 were injected into the cisterna magna of adult rats. Spinal cord irradiation reduced the number of O-2A cells in a dose-dependent manner. However, this radiation-induced decrease in O-2A progenitor cells was significantly attenuated by the delivery of GGF2 after irradiation. These data indicate that the cell-mediated delivery of GGF2 can reduce the loss of O-2A progenitors after irradiation.

Increased expression of prohormone convertase-2 in the irradiated rat brain

Changes in gene expression have been suggested to play a role in radiotherapy-induced central nervous system (CNS) injury. To begin to identify radiation-inducible genes in the CNS, we have applied the differential display of reverse transcription-polymerase chain reaction products to RNA extracted from the brain of adult rats. RNA was isolated from a rat brain 6 h after whole-body exposure to 10 Gy and compared with RNA from unirradiated brain. A cDNA band was consistently observed at about 600 bp in samples from the irradiated rat but not from unirradiated (control) rat. Amplification and sequencing of the cDNA revealed that it corresponded to the prohormone convertase-2 (PC2) gene, which is involved in the processing of inert prohormones and neuropeptides to their bioactive forms. Enhanced PC2 expression was detected after irradiation of neuronal cultures but not in cultures of astrocytes, suggesting that the cell type in the CNS responsible for the PC2 induction after in vivo irradiation is the neuron. These results indicate that radiation induces the expression of a neuronal enzyme that is critical to the activation of a number of prohormones and neuropeptides, which may influence the radioresponse of the CNS.

IkappaBalpha degradation is not a requirement for the X-ray-induced activation of nuclear factor kappaB in normal rat astrocytes and human brain tumour cells

PURPOSE

To investigate the mechanism of NFkappaB activation by X-rays in normal primary rat astrocytes.

MATERIALS AND METHODS

Primary cultures of type I astrocytes generated from the cortex of neonatal rats were exposed to X-rays with and without various kinase inhibitors and a protease inhibitor. The nuclear or cytoplasmic protein extracts were collected at specified times after treatment and analysed for NFkappaB-DNA binding activity and IkappaB protein levels.

RESULTS

The NFkappaB-DNA binding activity was induced by X-rays in a dose- and time-dependent manner in the absence of IkappaB protein degradation in astrocytes as well as in the human glioma cell line U-373MG. Whereas a protease inhibitor (calpain inhibitor 1) and a protein kinase C inhibitor (CGP-41251) did not affect X-ray-induced NFkappaB-DNA binding, treatment of astrocytes with the tyrosine kinase inhibitor (erbstatin) completely prevented the increase in NFkappaB activity after irradiation. Erbstatin also reduced the phosphorylation of IkappaBalpha after X-ray exposure.

CONCLUSIONS

These results indicate that, in contrast with the more frequently investigated activators of NFkappaB, radiation-induced activation of this transcription factor proceeds in the absence of IkappaBalpha degradation and requires tyrosine phosphorylation.

Acquisition of cellular resistance to 9-nitro-camptothecin correlates with suppression of transcription factor NF-kappa B activation and potentiation of cytotoxicity by tumor necrosis factor in human histiocytic lymphoma U-937 cells

Resistance of tumor cells to chemotherapeutic agents is a major problem in cancer therapy. Continuous exposure of human histiocytic lymphoma U-937 cells to 9-nitro-camptothecin (9NC), an inhibitor of the nuclear DNA topoisomerase I, induces resistance to this drug. Because of the involvement of the nuclear factor NF-kappa B in the expression of several growth regulatory genes, we examined the activation of this transcription factor in 9NC-resistant U-937 cells. We found that resistance to increasing concentrations of 9NC correlated with resistance to tumor necrosis factor (TNF)-dependent activation of NF-kappa B. However, the constitutive synthesis of NF-kappa B proteins remained unaffected. Cellular resistance was not unique to TNF, as other activators of NF-kappa B, including interleukin-1, phorbol ester and hydrogen peroxide, also had no effect. There was no difference between 9NC-sensitive and -resistant cells in the activation of NF-kappa B by okadaic acid. Other transcription factors, including AP-1 and Oct-1, were not affected in the resistant cells. When examined for the inhibitory subunit of NF-kappa B (I kappa B alpha), resistant cells showed a faster rate of resynthesis than the control. Interestingly, although 9NC resistance correlated with resistance to TNF-dependent NF-kappa B activation, TNF-dependent cytotoxicity in these cells was enhanced by several hundred fold despite a significant decrease in the number of TNF receptors. In conclusion, our results suggest that NF-kappa B activation may play a role in tumor cell killing by 9NC but not by TNF.

Enhancement of radiosensitivity of wild-type p53 human glioma cells by adenovirus-mediated delivery of the p53 gene

OBJECT

The authors sought to determine whether combining p53 gene transfer with radiation therapy would enhance the therapeutic killing of p53 wild-type glioma cells. It has been shown in several reports that adenovirus-mediated delivery of the p53 gene into p53 mutant gliomas results in dramatic apoptosis, but has little effect on gliomas containing wild-type p53 alleles. Therefore, p53 gene therapy alone may not be a clinically effective treatment for gliomas because most gliomas are composed of both p53 mutant and wild-type cell populations. One potential approach to overcome this problem is to exploit the role p53 plays as an important determinant in the cellular response to ionizing radiation.

METHODS

In vitro experiments were performed using the glioma cell line U87MG, which contains wild-type p53. Comparisons were made to the glioma cell line U251MG, which contains a mutant p53 allele. Monolayer cultures were infected with an adenovirus containing wild-type p53 (Ad5CMV-p53), a control vector (dl312), or Dulbecco's modified Eagle's medium (DMEM). Two days later, cultures were irradiated and colony-forming efficiency was determined. Transfection with p53 had only a minor effect on the plating efficiency of nonirradiated U87MG cells, reducing the plating efficiency from 0.23 +/- 0.01 in DMEM to 0.22 +/- 0.04 after addition of Ad5CMV-p53. However, p53 transfection significantly enhanced the radiosensitivity of these cells. The dose enhancement factor at a surviving fraction of 0.10 was 1.5, and the surviving fraction at 2 Gy was reduced from 0.61 in untransfected controls to 0.38 in p53-transfected cells. Transfection of the viral vector control (dl312) had no effect on U87MG radiosensitivity. In comparison, transfection of Ad5CMV-p53 into the p53 mutant cell line U251 MG resulted in a significant decrease in the surviving fraction of these cells compared with controls, and no radiosensitization was detected. To determine whether Ad5CMV-p53-mediated radiosensitization of U87MG cells involved an increase in the propensity of these cells to undergo apoptosis, flow cytometric analysis of terminal deoxynucleotidyl transferase-mediated biotinylated-deoxyuridinetriphosphate nick-end labeling-stained cells was performed. Whereas the amount of radiation-induced apoptosis in uninfected and dl312-infected control cells was relatively small (2.1 +/- 0.05% and 3.7 +/- 0.5%, respectively), the combination of Ad5CMV-p53 infection and radiation treatment significantly increased the apoptotic frequency (18.6 +/- 1.4%). To determine whether infection with Ad5CMV-p53 resulted in increased expression of functional exogenous p53 protein, Western blot analysis of p53 was performed on U87MG cells that were exposed to 9 Gy of radiation 2 days after exposure to Ad5CMV-p53, dl312, or DMEM. Infection with Ad5CMV-p53 alone increased p53 levels compared with DMEM- or dl312-treated cells. Irradiation of AdSCMV-p53-infected cells resulted in a further increase in p53 that reached a maximum at 2 hours postirradiation. To determine whether exogenous p53 provided by Ad5CMV-p53 had transactivating activity, U87MG cells were treated as described earlier and p21 messenger RNA levels were determined. Infection of U87MG cells with Ad5CMV-p53 only resulted in an increase in p21 compared with DMEM- and dl312-treated cells. Irradiation of AdSCMV-p53-infected cells resulted in an additional time-dependent increase in p21 expression.

CONCLUSIONS

These data indicate that adenovirus-mediated delivery of p53 may enhance the radioresponse of brain tumor cells containing wild-type p53 and that this radiosensitization may involve converting from a clonogenic to the more sensitive apoptotic form of cell death. Although the mechanism underlying this enhanced apoptotic susceptibility is unknown, the AdSCMV-p53-infected cells have a higher level of p53 protein, which increases further after irradiation, and this exogenous p53 is transcriptionally active. (ABSTRACT TRUNCATE

Effect of bile acids and estradiol on thymidine incorporation into DNA in MCF-7 and MCF-10A breast cell lines

Bile acid conjugates are found in human breast cyst fluid in average concentrations about 50-fold greater than those in blood. Because epidemiologic studies have linked colon and breast cancer and aberrant bile acid profiles are associated with colon cancer risk, we decided to study the influence of bile acid conjugates (glycochenodeoxycholic acid, glycodeoxycholic acid, glycocholic acid, and glycolithocholic acid) on thymidine incorporation into DNA in cancer (MCF-7) and noncancer (MCF-10A) human mammary cell lines. The two lines responded differently. In MCF-7, bile acids, except for glycolithocholic acid, stimulated thymidine incorporation. Estradiol caused even greater stimulation, an effect that was not influenced further by the addition of bile acids. Bile acids suppressed incorporation in MCF-10A cells. Estradiol at 1 nM had no effect, but 10 nM estradiol was stimulatory. In most cases bile acids appeared to diminish the incorporations observed with estradiol alone, but not significantly. The relevance of these studies to the possible impact of bile acids on the course of fibrocystic disease of the breast would require further investigation.

Failure of a second X-ray dose to activate nuclear factor kappaB in normal rat astrocytes

Induced gene expression and subsequent cytokine production have been implicated in the normal tissue injury response to radiotherapy. However, studies of radiation-induced gene expression have used single radiation doses rather than the fractionated exposures typical of the clinical situation. To study the effects of multiple radiation doses on gene expression, we investigated nuclear factor kappaB (NFkappaB) DNA binding activity in primary astrocyte cultures after one and two exposures to x-rays. After a single dose of x-rays (3.8-15 gray (Gy)), NFkappaB binding activity in astrocytes increased in a dose-dependent manner, reaching a maximum by 2-4 h and returning to control levels by 8 h after irradiation. In split-dose experiments, when an interval of 24 h was used between two doses of 7.5 Gy, the second 7.5-Gy exposure failed to induce NFkappaB activation. The period of desensitization induced by the first radiation exposure was dose-dependent, persisting approximately 72 h after 7.5 Gy compared with 24 h after 1.5 Gy. No changes in IkappaBalpha protein levels were detected. However, the presence of a transcription inhibitor prevented the desensitizing effect of the initial irradiation. Irradiation also prevented NFkappaB activation in astrocytes by a subsequent exposure to H2O2, but it had no effect on the activation induced by tumor necrosis factor-alpha. These data indicate that an initial x-ray exposure can desensitize astrocytes to the NFkappaB-activating effects of a subsequent radiation exposure. Furthermore, they suggest that this desensitization depends on gene transcription and may have some specificity for NFkappaB activation mediated by reactive oxygen species.

Epstein-Barr Virus EBNA-2 gene expression enhances lymphotoxin production by B lymphocytes

Epstein-Barr Virus (EBV) effectively transforms B lymphocytes into long-term cell lines or tumors through the interaction of viral gene products and cellular proteins induced secondary to the virus infection. The latent membrane protein (LMP) gene, the EBV nuclear antigens (EBNAs) 1 and 2, and the origin of replication genes of the virus are the principal viral effectors of transformation. One of the cellular proteins that enhances the growth and proliferation of B cells is lymphotoxin (LT). We have found that Burkitt's lymphoma cells containing a strain of EBV with a deletion in EBNA-2 had lower constitutive and inducible levels of LT compared to LT production in Burkitt's cells with competent EBV or lymphoblastoid cell lines actively producing EBV. Also, the LT production in the latter cell lines was greater than in cells in which the infecting EBV had a deletion in the LMP gene. The relative decrease in LT production associated with deletions in the LMP was less than that found with EBNA-2 deletions. Overall our results indicate that the EBNA-2 gene enhances the capacity of EBV-infected cells to produce LT.

Breast papillomas with atypical ductal hyperplasia: a clinicopathologic study

Breast papillomas with areas of atypical proliferation reminiscent of ductal carcinoma in situ (DCIS) and atypical ductal hyperplasia (ADH) are rare, but pose considerable diagnostic difficulty when encountered. The clinicopathologic features of 20 women 27 to 78 years of age with papillomas having atypical proliferations are reviewed. They presented with palpable masses or nipple discharge. Histologically, parts of all lesions had features of papillomas with a biphasic proliferation of benign epithelial cells and myoepithelial (ME) cells. Part of the lesion in each papilloma also had an expansile proliferation of larger uniform cells having evenly spaced, round nuclei and a solid to subtle cribriform growth pattern, similar to ADH or DCIS. These lesions tended to be large, complex or multiple. Twelve patients had 4 to 20 years of follow-up after biopsy only. One each had concurrent and previous contralateral breast carcinoma. Two developed invasive carcinoma of the contralateral breast in 15 and 18 years, respectively. Two developed DCIS on the same side in 2 and 8 years. Six had recurrent papillomas with (5) or without (1) ADH in 1 to 7 years all of whom had no further problems. Only 3 of 12 patients are event free. In contrast, only 8 recurrent papillomas, and 1 ipsilateral invasive carcinoma and 2 contralateral carcinomas occurred in 60 patients with papillomas without ADH in 4 to 18 years. Thus, the patients having ADH within papillomas seem to have greater likelihood of subsequent disease such as recurrences or overt neoplasia, but the length of follow-up and number of patients are not large enough to provide definitive answers. Because none of the patients developed invasive carcinoma on the same side, conservative management with close observation similar to that following a diagnosis of ADH seems to be appropriate.

Differential activation of the nuclear factor-kappa B by TNF muteins specific for the p60 and p80 TNF receptors

Human TNF is a highly pleiotropic cytokine that mediates its effects by binding to two distinct receptors, viz p60 and p80, which transmit their signals independently of each other. Activation of the transcription factor NF-kappa B is one of the earliest events induced by TNF, but whether it is mediated through one or both forms of the TNF receptor is controversial. in the present studies, we examined the role of each receptor in the activation of NF-kappa B by using TNFs that has been designed by site-specific mutagenesis to bind either the p60 (R32W; S86T) or the p80 (D143N; A145R) form of the receptor. Human myelogenous leukemic ML-1 a cells known to express almost equal amounts of the two receptors were used. The binding of TNF to these cell could be inhibited equally by either TNF(p60) or TNF(p80) mutein. Treatment of these cells with TNF(p60) mutein activate NF-kappa B within 30 min, whereas TNF(p80) mutein, even at a 1000-fold excess, had no effect, suggesting that the activation of NF-kappa B is differentially regulated through the p60 receptor. Consistent with these results, treatment with either anti-p80 monoclonal or polygonal Abs blocked the binding of TNF to the p80 receptor without affecting TNF-mediated activation of NF-kappa B TNF(p60) mutein was also effective in cell killing, but the TNF(p80) mutein was totally ineffective. The effect was not cell type-specific, since other p80-expressing cell lines were also unresponsive. Overall, our results clearly demonstrate that the activation of NF-kappa B and cytotoxicity by TNF is differentially regulated through the p60 receptor.

Differential activation of the nuclear factor-kappa B by TNF muteins specific for the p60 and p80 TNF receptors

Human TNF is a highly pleiotropic cytokine that mediates its effects by binding to two distinct receptors, viz p60 and p80, which transmit their signals independently of each other. Activation of the transcription factor NF-kappa B is one of the earliest events induced by TNF, but whether it is mediated through one or both forms of the TNF receptor is controversial. in the present studies, we examined the role of each receptor in the activation of NF-kappa B by using TNFs that has been designed by site-specific mutagenesis to bind either the p60 (R32W; S86T) or the p80 (D143N; A145R) form of the receptor. Human myelogenous leukemic ML-1 a cells known to express almost equal amounts of the two receptors were used. The binding of TNF to these cell could be inhibited equally by either TNF(p60) or TNF(p80) mutein. Treatment of these cells with TNF(p60) mutein activate NF-kappa B within 30 min, whereas TNF(p80) mutein, even at a 1000-fold excess, had no effect, suggesting that the activation of NF-kappa B is differentially regulated through the p60 receptor. Consistent with these results, treatment with either anti-p80 monoclonal or polygonal Abs blocked the binding of TNF to the p80 receptor without affecting TNF-mediated activation of NF-kappa B TNF(p60) mutein was also effective in cell killing, but the TNF(p80) mutein was totally ineffective. The effect was not cell type-specific, since other p80-expressing cell lines were also unresponsive. Overall, our results clearly demonstrate that the activation of NF-kappa B and cytotoxicity by TNF is differentially regulated through the p60 receptor.

Identification of three proteins in the eye of Aplysia, whose synthesis is altered by serotonin (5-HT). Possible involvement of these proteins in the ocular circadian system

Previous results using translation inhibitors in the ocular circadian system of Aplysia suggest that protein synthesis may be involved in the light and serotonin (5-HT) entrainment pathways or perhaps in the circadian oscillator. Proteins have been previously identified whose synthesis was altered by treatments of light capable of perturbing the phase of the circadian rhythm in the eye of Aplysia. We extended these studies by investigating the effects of other treatments that perturb the ocular circadian rhythm on protein synthesis. 5-HT altered the synthesis of nine proteins. Interestingly, five of the proteins affected by treatments with 5-HT were previously shown to be affected by treatments with light. Four of the proteins affected by treatments with 5-HT were also affected by treatments with analogs of cAMP, a treatment which mimics the effects of 5-HT on the ocular circadian rhythm. To identify the cellular function of some of these proteins, we obtained their partial amino acid sequences. Based on these sequences and additional characterizations, a 78-kDa, pI 5.6 Aplysia protein appears to be glucose-regulated protein 78/binding protein, and a 36-kDa, pI 5.7 Aplysia protein appears to be porin/voltage-dependent anion channel. Heat shock experiments on Aplysia eyes revealed that yet another one of the Aplysia proteins (70 kDa) affected by 5-HT appears to be a heat-inducible member (heat shock protein 70) of the family of heat shock proteins. These findings suggest that these three identified proteins, together or individually, may be involved in some way in the regulation of the timing of the circadian oscillator in the eye of Aplysia.

Effects on protein synthesis produced by pairing depolarization with serotonin, an analogue of associative learning in Aplysia

A form of associative plasticity in Aplysia, activity-dependent neuromodulation, involves the convergence of neuronal activity and the effects of a modulatory transmitter. To investigate the role of protein synthesis in associative plasticity, we examined the effects of a biochemical analogue of activity-dependent neuromodulation on the level of incorporation of labeled amino acid into proteins. To mimic associative training, abdominal ganglia were exposed to paired treatments of a depolarizing agent, elevated potassium, and a modulatory transmitter, serotonin. The effects of elevated potassium and serotonin applied alone were also examined. At least two proteins (nos. 9 and 17) were affected in a nonadditive way by the paired procedure. Incorporation of label into protein 9 was increased by the paired procedure but was not affected by either elevated potassium or serotonin. Incorporation of label into protein 17 was significantly affected by elevated potassium or serotonin, but the effect of the paired procedure was significantly less than the summed effects of elevated potassium and serotonin applied alone. These results indicate that changes in protein synthesis may be important in the induction of associative plasticities. Amino acid sequences of two peptides derived from protein 9 were obtained. Then, a partial cDNA clone for protein 9 was obtained by performing PCR with degenerate primers corresponding to portions of the sequences of the two peptides. The sequence of protein 9 is related to sequences previously reported for a family of genes comprising the stringent starvation protein of Escherichia coli, auxin-induced proteins of plants, and glutathione S-transferases of a number of organisms.

Breast-gut connection: origin of chenodeoxycholic acid in breast cyst fluid

The notion that a breast-gut connection might modulate the microenvironment of breast tissue was supported by the finding that breast cyst fluid contains bile acids that are characteristically found in the intestines. To establish that the gut, rather than circulating steroid precursors, is the source of bile acids in breast cyst fluid, we gave two patients deuterium-labelled chenodeoxycholic acid (three 200 mg doses by mouth), starting 9 days before aspiration of breast cysts. The chenodeoxycholic acid concentration of seven samples of aspirated cyst fluid ranged from 42 to 94 mumol/L. The corresponding serum concentrations of chenodeoxycholic acid on the same day were 0.8 and 2.9 mumol/L, of which the labelled compound comprised 13.0% (0.38 mumol/L) and 28.2% (0.23 mumol/L). The deuterated chenodeoxycholic acid concentrations in cyst fluid were 0.79 and 1.26 mumol/L in two samples from patient 1 and 3.22 mumol/L in patient 2; these values are equivalent to 11-17% of the serum concentrations [corrected]. This study shows that intestinal bile acids rapidly gain access to cyst fluid. Further studies should investigate the mechanisms that govern the exchange processes and the maintenance of the high cyst fluid to plasma concentration gradients, and the biological half-lives of individual constituents.

Noninvasive breast cancer

Noninvasive breast cancer comprises two distinct entities, lobular carcinoma in situ (LCIS) and ductal carcinoma in situ (DCIS). The increased use of screening mammography has caused more cases of noninvasive breast cancer to be discovered. However, the increased detection of LCIS and DCIS has posed problems in patient care for the radiologist, pathologist, surgeon, radiation oncologist, and medical oncologist. The authors review the past history of LCIS and DCIS, as well as the diagnostic challenges and therapeutic considerations for the multidisciplinary breast cancer team.

Identification of an annexin-like protein and its possible role in the Aplysia eye circadian system

Light and serotonin regulate the phase of the circadian rhythm of the isolated eye of Aplysia. To screen for possible protein components of the eye circadian oscillator, we identified a number of proteins whose synthesis was altered in opposite ways by light and serotonin. The cellular function of one of these proteins was investigated by obtaining a partial amino acid sequence of it and by examining its immunoreactivity. A 38-amino acid sequence was obtained from a 40-kDa (isoelectric point 5.6) protein. A greater than 60% amino acid identity existed between this sequence and sequences of a family of calcium/phospholipid-binding proteins called annexins. Furthermore, the 40-kDa protein reacted with antibodies generated against a conserved amino acid sequence of annexins and with antibodies raised against human annexin I. The identification of the 40-kDa, light- and serotonin-regulated protein as an annexin led us to hypothesize that arachidonic acid metabolism plays a role in the Aplysia eye circadian system. To test this hypothesis, we examined the ability of an inhibitor of the arachidonic acid metabolic pathway to perturb the eye rhythm. Pulse treatments of isolated eyes with a lipoxygenase inhibitor, nordihydroguaiaretic acid, phase shifted the rhythm. The phase-shifting ability of nordihydroguaiaretic acid suggests that arachidonic acid and some of its metabolites may play a role in the eye circadian system. The results of our studies raise the possibility that links may exist between the 40-kDa annexin-like protein, arachidonic acid metabolism, and the circadian oscillator.

Signet ring variant of lobular carcinoma of the breast: a clinicopathologic and immunohistochemical study

Signet ring carcinoma of the breast often metastasizes to gastrointestinal tract and female genital tract. We report clinicopathologic features of 10 breast carcinomas with signet ring features, five of which had unusual metastatic patterns. The primary breast tumor in all these cases was lobular carcinoma. Although signet ring cells were prominent in metastatic sites, the primary tumor lacked signet ring cells in two cases. A linitis plastica-like presentation and presence of signet ring cells in gastric metastases raised a strong possibility of primary gastric carcinoma in three cases. The monoclonal antibody to gross cystic disease fluid protein (GCDFP-15) was positive in signet ring cell-rich areas in the primary breast tumor (8/10) and/or in the metastases in all cases. For comparison we studied GCDFP-15 immunoreactivity in 10 infiltrating lobular and 10 infiltrating ductal breast carcinomas with no obvious signet ring cells, and in 14 signet ring carcinomas from other sites (10 gastric, 2 prostatic, 2 colonic). The gastric, colonic, and one prostatic signet ring carcinoma were nonreactive. One prostatic signet ring carcinoma exhibited focal but unequivocal positivity with GCDFP-15. The cases of this report reinforce the concept that signet ring carcinoma of the breast is usually a variant of lobular carcinoma and not a distinct entity. Signet ring cell predominance in metastases, even in the absence of signet ring cells in the primary tumor, attest to the morpho-functional heterogeneity of lobular carcinoma. GCDFP-15 is a sensitive marker for signet ring breast carcinoma and a very useful adjunct tool in the diagnosis of metastatic signet ring carcinoma of mammary origin.

The histologic spectrum of apocrine breast proliferations: a comparative study of morphology and DNA content by image analysis

Apocrine features occurring in sclerosing adenosis (apocrine adenosis), atypical ductal hyperplasia (ADH), and non-comedo ductal carcinoma in situ (DCIS) often add to diagnostic difficulty. We have evaluated the usefulness of DNA content determined by image analysis in apocrine metaplasia and hyperplasia, apocrine adenosis, ADH, DCIS, lobular carcinoma in situ, invasive ductal carcinoma, and infiltrating lobular carcinoma as a potential diagnostic aid in some of these problematic breast lesions with apocrine features. Infiltrating ductal carcinoma and DCIS were further subdivided into high- or low-grade category based on nuclear features. Microscopic fields containing 63 lesions were identified in slides from breast excisions. From each selected area 100 cells in corresponding fields in paired Feulgen-stained sections were digitized for computerized ploidy analysis with lymphocyte nuclei in the same slides serving as internal diploid controls. Aneuploidy was assessed using combined DNA index and modified Auer histogram criteria for DNA content abnormalities. There was strong association between the assessment of nuclear grade and ploidy (Fisher's exact test, P < .00001). All but one of the benign and low-grade malignant lesions (97%) were in the diploid range (six of seven apocrine metaplasia cases, three of three apocrine adenosis cases, 14 of 14 ADH cases, 10 of 10 low-grade DCIS cases, two of two lobular carcinoma in situ cases, and two of two infiltrating lobular carcinoma cases). In contrast, 24 of 25 (96%) of the high-grade malignant lesions were aneuploid (10 of 10 DCIS cases and 14 of 15 infiltrating ductal carcinoma cases). We conclude that DNA ploidy status does not offer additional diagnostic information to light microscopy in distinguishing among benign apocrine proliferations, ADH, and low-grade DCIS since these proliferations share a diploid range DNA content.

Esterase activity in human breast cyst fluid: associations with steroid sulfates and cations

Human breast cyst fluid (BCF) contains an esterase that on the basis of electrophoretic mobility and response to inhibitors differs from those found in the plasma. From a total of 384 BCF samples analyzed for esterase using p-nitrophenyl hexanoate as substrate, 149 (39%) showed significant activity. The samples had been analyzed for the concentrations of the sulfates of estrone, estriol, dehydroepiandrosterone, as well as the potassium and sodium cations (K+/Na+). The data were submitted to statistical analysis using the Spearman rank order test. The esterase-positive samples exhibited a significant positive association with each of the steroid sulfates and the K+/Na+ ratios. Except for protein concentration, there was no significant correlation between the esterase-positive and esterase-negative cysts. These observations may have physiological significance in that high K+/Na+ ratio cysts have been related to the histological status of the cyst.

Relationship between the concentrations of estriol sulfate and estrone sulfate in human breast cyst fluid

Estriol-3-sulfate (E3S) is present in human breast cyst fluid (BCF) in median levels of 8.7-10.4 nmol/L, yet is barely detectable in the serum (less than 0.034 nmol/L). The source of this huge concentration of E3S is unknown. It may accumulate from blood by active transport or be synthesized and concentrated within the cyst. Since estrone sulfate (E1S) and its possible precursor, dehydroepiandrosterone sulfate (DHEAS) are elevated in BCF, E3S may originate via 16 alpha-hydroxylation of E1S. The present study examined the correlations between the levels of DHEAS and E1S with those of E3S in BCF. The sodium and potassium ions were also quantified and related to the steroid concentrations. By linear regression analysis of log-normalized data there was a highly significant correlation between the concentrations of E1S and E3S (n = 355, r = 0.690, P less than 0.001) and between DHEAS and E3S (n = 361, r = 0.577, P less than 0.001). The BCF were classified according to their K/Na ion ratios: type 1, greater than 1.0, type II, less than 0.25, and type III, 0.25-1.0. By Student's t test, the concentrations of E3S differed between each BCF Type (P less than 0.002). This was also true for E1S and DHEAS. Type 1 cysts were associated with the highest estrogen sulfate levels and type II with the lowest levels. The possible physiological importance of this observation resides in reports that the BCF type expressing the highest steroid concentrations has been related to an aporcine-like epithelial lining of the cyst wall and a somewhat higher risk for developing breast cancer. The results suggest that E3S in BCF may originate from E1S, but alternate mechanisms are not precluded.

Alteration of the phase and period of a circadian oscillator by a reversible transcription inhibitor

A function for transcription in the mechanism of a circadian oscillator was investigated with the reversible transcription inhibitor 5,6-dichloro-1-beta-D- ribobenzimidazole (DRB). Two-hour treatments with DRB shifted the phase of the circadian rhythm of the isolated eye of Aplysia, and continuous treatments of DRB lengthened the free running period of this rhythm. Camptothecin, an inhibitor of transcription that is structurally unrelated to DRB, had similar effects on the circadian rhythm. These results suggest that transcription may be part of the circadian oscillating mechanism.

ECG changes in asphyxia neonatorum

Twenty five asphyxiated neonates had ECG changes consistent with degree of asphyxia. Equivocal changes were found in mild asphyxia and changes suggestive of myocardial infarction were seen with severe asphyxia. In most cases, the changes reverted to normal within two weeks signifying great ability of the neonatal heart to withstand hypoxic insult. Four babies with severe asphyxia having ECG changes suggestive of acute myocardial infarction expired within 48 hours of birth.

Epitheliosis of the breast. An immunohistochemical characterization and comparison to malignant intraductal proliferations of the breast

Epitheliosis is a benign intraluminal proliferation in the breast ducts and lobules that needs to be distinguished from ductal carcinoma in situ (DCIS). The histogenesis and differentiation of cells comprising epitheliosis have been the subject of some controversy. We evaluated the expression of a high-molecular-weight keratin (34 beta E12), muscle-specific actin (HHF-35), and S-100 protein immunoreactivity in formalin-fixed sections of the breast with epitheliosis and DCIS. In 28 of 30 cases of epitheliosis, there was strong HMW keratin immunoreactivity in the streaming sheetlike intraluminal proliferations. In contrast, 35 of 40 cases of DCIS (nonpapillary and papillary) were nonreactive for HMW keratin; the other five were weakly reactive. Furthermore, in 10 cases of DCIS, some ducts had isolated or small aggregates of HMW keratin-positive benign cells on the luminal aspects of the neoplastic proliferation that were reminiscent of a pagetoid pattern. Muscle actin-stained sections were analyzed to assess myoepithelial (ME) cell participation in epitheliosis. Muscle actin-positive ME cells were present at the periphery of the involved ducts but were absent or rare within epitheliosis. The distribution of ME cells--i.e., at the periphery of the spaces involved--was similar in DCIS and epitheliosis. S-100 protein was weakly but relatively consistently expressed by epitheliosis, but all cases of DCIS were negative. Six cases of atypical ductal hyperplasia included in the study were negative for HMW keratin, muscle actin, and S-100 protein. The immunohistochemical profile of epitheliosis indicates that it is primarily an epithelial proliferation with strong HMW keratin and weak S-100 protein expression but without ME cell participation. The distinct differences in HMW keratin expression of epitheliosis and intraductal carcinoma appear to reflect a consistent antigenic difference in these two biologically distinct forms of proliferation.

A comparative immunohistochemical study of peritoneal and ovarian serous tumors, and mesotheliomas

The distinction between serous neoplasms of the peritoneum in women and conventional mesothelioma can be difficult. In order to determine any significant immunohistochemical differences, formalin-fixed, paraffin-embedded sections of 10 peritoneal serous tumors (PST), 10 ovarian serous tumors (OST), and 10 epithelial mesotheliomas were evaluated with a panel of 10 antibodies directed against carcinoembryonic antigen (CEA: polyclonal, monoclonal), high molecular weight keratin (34 beta E12), low molecular weight keratin (35 beta H11), Leu-M1, TAG-72 (monoclonal antibody B72.3), human milk fat globulin (HMFG-2), vimentin, placental alkaline phosphatase (PLAP), and S-100 protein. The antibodies CEA, Leu-M1, and B72.3 had the most discriminatory value in differentiating serous tumors from mesothelioma. Eighty-five percent of PSTs and OSTs (17 of 20) were positive with CEA, Leu-M1, and/or B72.3. None of the mesotheliomas stained for CEA or Leu-M1; three mesotheliomas had very focal positivity with B72.3 (1% or less). Vimentin, PLAP, HMGF-2, keratin, and S-100 had no significant discriminatory value. Epithelial mucin was present in 80% of serous tumors, while the mesotheliomas lacked epithelial mucin. Leu-M1, CEA, and/or B72.3 positivity in a peritoneal tumor supports a diagnosis of serous tumor. However, since some PST do not stain for any of the three antibodies and the focal nature of positive reactions in some cases may be difficult to interpret, exclusion of mesotheliomas is enhanced by the use of mucin stains.

Bile acids in human breast cyst fluid: the identification of lithocholic acid

Breast cyst fluid (BCF) aspirated from 12 women with fibrocystic disease of the breast and sera obtained simultaneously were analyzed for bile acids. Analysis was performed by gas-liquid chromatography of the acetoxy methyl esters of the bile acids prepared after alkaline hydrolysis of the bile salts. An internal standard served to correct for methodological losses. Low levels of bile acids were found in serum samples, precluding overt hepatobiliary complications. Deoxycholic acid (17-160 mumol/L), chenodeoxycholic acid (18-305 mumol/L), and cholic acid (3-119 mumol/L) were detected in 11 of 12 samples of BCF. In 2 cases, chosen at random, the identities of the bile acids were verified by mass spectrometry. Lithocholic acid (9-23 mumol/L), a reported cocarcinogen, was detected in 6 of the 12 samples of BCF. This is the first report of the presence of lithocholic acid in BCF with confirmation by Mass spectrometry. There was no correlation between the levels of individual bile acids and those of potassium ion, Na+/K+, estriol-3-sulfate, or 16 alpha-hydroxyandrogen sulfates that had been quantified previously in these samples. There was borderline correlation between concentrations of total bile acids and K+ (P less than 0.06) and Na+/K+ (P less than 0.07). Yet to be elucidated are the mechanism of accumulation of bile acids in BCF and whether levels of particular bile acids in BCF may serve to identify that small subset of women with fibrocystic disease at risk for developing breast cancer.