Evidence for fatty acid oxidation in human placenta, and the relationship of fatty acid oxidation enzyme activities with gestational age.

Fetal disorders of mitochondrial fatty acid oxidation have recently been associated with obstetric complications including pre-eclampsia, Hemolysis, Elevated Liver enzymes, Low Platelets (HELLP) syndrome, placental floor infarct, and Acute Fatty Liver of Pregnancy (AFLP). These diseases occur in about a third of the mothers who are heterozygous for a defect in long chain 3-hydroxyacyl-CoA dehydrogenase (LCHAD) enzyme and who bear a fetus homozygous for the defect. The mechanism of this association is not clearly understood. In this study, we provide evidence that the placenta may be the site of production of toxic intermediates of fatty acid metabolism, which accumulate to cause liver damage in the mother. We show that two critical enzymes of long chain fatty acid metabolism, long chain 3-hydroxyacyl-CoA dehydrogenase (LCHAD) and short chain 3-hydroxyacyl-CoA dehydrogenase (SCHAD), are active in the normal human placenta. There is an inverse correlation between the enzyme activity of both the enzymes and maternal gestational age during the second and third trimesters. We believe that the demonstration of fatty acid oxidation enzyme activity by the placenta is the first step towards assessing a possible role for fetal/placental fatty acid oxidation defects in the pathogenesis of a subset of pregnancy complications.

Mucositis in the oncology patient.

Mucositis is a common side effect related to the treatment of cancer. Many agents have been tested for the prevention and management of mucositis, but the data regarding a number of the agents are conflicting. This article describes the incidence of mucositis in individuals with cancer and the various agents used in its prevention and management. Nurses play an important role in the management of patients with mucositis and in identifying agents that may decrease the patient's risk for mucositis and aid healing.

Prevalence and cellular reservoir of latent human herpesvirus 6 in tonsillar lymphoid tissue.

There are few studies that examine prevalence, quantity, and cellular proclivity of latent human herpesvirus 6 (HHV-6) in healthy populations. We examined 69 tonsils with paired blood specimens from children without evidence of acute infection. By polymerase chain reaction (PCR), HHV-6 was detected at low levels in 100% of tonsils and 39% of blood samples (n = 27), suggesting that prevalence of latent HHV-6 infection is high in children and may be underestimated by PCR analysis of blood. Although HHV-6A and HHV-6B were detected, HHV-6B predominated, being found in 97% of samples (n = 67). Tonsil sections from 7 cases were examined by in situ hybridization using 2 HHV-6 probes and immunohistochemical analysis. Using both in situ hybridization and immunohistochemical analysis, all tissues revealed marked HHV-6-specific staining in the squamous epithelium of the tonsillar crypts and rare positive lymphocytes. We conclude that HHV-6 is present universally in tonsils of children, and tonsillar epithelium may be an important viral reservoir in latent infection.

Elevated cytokine and chemokine levels and prolonged pulmonary airflow resistance in a murine Mycoplasma pneumoniae pneumonia model: a microbiologic, histologic, immunologic, and respiratory plethysmographic profile.

Because Mycoplasma pneumoniae is hypothesized to play an important role in reactive airway disease/asthma, a comprehensive murine model of M. pneumoniae lower respiratory infection was established. BALB/c mice were intranasally inoculated once with M. pneumoniae and sacrificed at 0 to 42 days postinoculation. All mice became infected and developed histologic evidence of acute pulmonary inflammation, which cleared by 28 days postinoculation. By contrast, M. pneumoniae persisted in the respiratory tract for the entire 42 days studied. Tumor necrosis factor alpha, gamma interferon, interleukin-6 (IL-6), KC (functional IL-8), MIP-1alpha, and MCP-1/JE concentrations were significantly elevated in bronchoalveolar lavage samples, whereas IL-4 and IL-10 concentrations were not significantly elevated. Pulmonary airflow resistance, as measured by plethysmography, was detected 1 day postinoculation and persisted even after pulmonary inflammation had resolved at day 28. Serum anti-M. pneumoniae immunoglobulin G titers were positive in all mice by 35 days. This mouse model provides a means to investigate the immunopathogenesis of M. pneumoniae infection and its possible role in reactive airway disease/asthma.

Cytomegalovirus and human herpesvirus 6, but not human papillomavirus, are present in neonatal giant cell hepatitis and extrahepatic biliary atresia.

The purpose of our study was to confirm reports of an association of human papillomavirus (HPV) with neonatal giant cell hepatitis (GCH) and biliary atresia (BA), and to expand these studies to include cytomegalovirus (CMV), Epstein-Barr virus (EBV), human herpesvirus 6 (HHV6), and parvovirus B19 (PVB19). Frozen hepatic tissue was available for polymerase chain reaction (PCR) analysis in 19 cases of GCH or BA and 8 controls. Nested PCR to detect HPV types 6, 16, 18, and 33 was followed by 32P hybridization with generic probes. PCR followed by hybridization with a digoxigenin-labeled probe was used for all other viruses. HPV, EBV, and PVB19 were not detected in cases or controls. Two cases of GCH and 1 case of BA were PCR positive for CMV; controls were negative. HHV6 was detected in 6 cases: 2 GCH, 2 BA, and 2 controls. We conclude that HPV is not associated with GCH or BA. Detection of CMV in BA and GCH confirms other reports of this association. HHV6 requires further study to determine the significance of a positive PCR test in the livers of infants.

In utero development of hypertensive necrotizing pulmonary arterial lesions: report of a case associated with premature closure of the ductus arteriosus and pulmonary hypoplasia.

Premature closure of the ductus arteriosus (PCDA) is an uncommon defect in which pulmonary hypertension (PH) has been documented by echocardiography in patients and by direct measurement after experimental PCDA in animals. The pulmonary vascular histology in human cases has received little attention but in the few recorded observations the vessels were either normal or showed increased muscularity. We report the case of a 31 week hydropic female stillborn monozygotic twin in whom postmortem examination disclosed PCDA and hypoplasia of the lungs. Atypical plexiform lesions with necrotizing pulmonary arteritis were present. These lesions represent vascular consequences of severe pulmonary hypertension produced by greatly enhanced blood flow through a restricted vascular bed resulting from the combined effects of these two abnormalities. The findings in this case of PCDA with presumed severe PH indicate that severe pulmonary vascular changes can develop in utero and that the interval of time needed for development of such chances in secondary PH is relatively short.

Unusual bone marrow manifestations of parvovirus B19 infection in immunocompromised patients.

Parvovirus B19 is responsible for a spectrum of disease in humans. The usual bone marrow findings in acute parvovirus infections are marked erythroid hypoplasia and occasional giant erythroblasts. Intranuclear inclusions in developing erythroid precursors are rarely described in children or adults with parvovirus infection, although abundant intranuclear inclusions are commonly observed in the placenta and other tissues in infected fetuses. In this study, 8 patients are reported in whom the first evidence of parvovirus infection was the recognition of numerous intranuclear inclusions in erythroid precursors on bone marrow biopsy sections. Six of the 8 patients had documented immunodeficiencies; 4 had acquired immune deficiency syndrome (AIDS), and 2 were on chemotherapy. Five of 7 patients were negative for immunoglobulin G (IgG) antiparvovirus antibodies, including all 4 with AIDS. Unlike the typical pattern in parvovirus infection, the bone marrow was hypercellular in most of the patients, and erythroid precursors were usually increased with the entire spectrum of normoblast maturation represented; abundant intranuclear inclusions were observed similar to the finding in fetuses. The inclusions were variably eosinophilic and compressed the chromatin against the nuclear membrane. In situ hybridization showed parvovirus B19 DNA in numerous erythroid precursors in all cases. The findings of erythroid maturation and abundant viral inclusions in these immunocompromised patients is consistent with the hypothesis that failure to produce effective IgG parvovirus neutralizing antibodies may lead to persistent infection through viral tolerance that allows erythroid development of infected cells past the pronormoblast stage. Identification of parvovirus inclusions in marrow biopsies and subsequent confirmation of infection by in situ hybridization can be important in the assessment of anemia in immunodeficient patients because serological studies for parvovirus B19 are frequently negative.

Predictive value of quantitative PCR-based viral burden analysis for eight human herpesviruses in pediatric solid organ transplant patients.

Human herpesviruses can cause significant morbidity and mortality in pediatric solid organ transplant recipients. It was hypothesized that viral burden quantification by polymerase chain reaction using an internal calibration standard could aid in distinguishing between viral disease and latency. Here we report the results of a 2-year prospective study of 27 pediatric solid organ (liver, kidney, or heart) transplant recipients in which multiple samples were analyzed for levels of all eight human herpesviruses by internal calibration standard-polymerase chain reaction. Herpes simplex viruses 1 and 2, varicella-zoster virus, and Kaposi's sarcoma-associated herpesvirus were not detected in any of these samples. Human herpesvirus types 6 and 7 were detected in half of the patients, but were present at low levels, similar to those found in reference populations. Epstein-Barr virus (EBV) and cytomegalovirus (CMV) were detected in 89% and 56% of the patients, respectively. Viral burden analysis suggested distinct patient populations for CMV, with a natural cutoff of 10,000 viral targets/ml blood strongly associated with disease. In some cases, a dramatic increase in CMV levels preceded clinical evidence of disease by several weeks. EBV viral burden was relatively high in the only patient presenting with an EBV syndrome. However, two other patients without evidence of EBV disease had single samples with high EBV burden. Rapid reduction in both EBV and CMV burden occurred with antiviral treatment. These data suggest that viral burden analysis using internal calibration standard-polymerase chain reaction for CMV, and possibly other herpesviruses, is an effective method for monitoring pediatric transplant patients for significant herpesvirus infection and response to therapy.

Quantitation of 8 human herpesviruses in peripheral blood of human immunodeficiency virus-infected patients and healthy blood donors by polymerase chain reaction.

Human herpesviruses are associated with morbidity and mortality in persons with compromised immune systems, including patients infected with human immunodeficiency virus (HIV). To investigate the basis for this association, the levels of all 8 human herpesviruses (herpes simplex virus, types 1 and 2, varicella-zoster virus, cytomegalovirus, Epstein-Barr virus, and human herpesvirus 6, human herpesvirus 7, and human herpesvirus 8) were measured with the quantitative polymerase chain reaction (PCR). Viral DNA was measured in the whole blood of 20 HIV-infected patients and compared with levels in 20 healthy blood donors. There was no significant difference in the frequency of virus detection of the 8 human herpesviruses between HIV-infected patients and healthy adults. These results indicate that HIV infection is not associated with a general increase in the circulating levels of human herpesviruses, and suggest that quantitative PCR analysis is superior to qualitative PCR analysis for detection of clinically relevant disease in HIV-infected patients.

Human herpesvirus-6 and sudden death in infancy: report of a case and review of the literature.

Investigation of sudden death in infancy is a vital function of the medical examiner's office. Surveillance of these cases may lead to recognition of new diseases or new manifestations of previously described diseases. Human herpesvirus-6 (HHV-6) is a relatively newly described virus that has been recognized as a cause of acute febrile illness in early childhood. While most cases are apparently self-limited, seven fatal cases have been reported. We present a case of a seven-month-old Latin American male with recent otitis media and vomiting who was found dead in bed. Autopsy revealed interstitial pneumonitis with an atypical polymorphous lymphocytic infiltrate in the liver, kidney, heart, spleen, lymph nodes, and bone marrow, associated with erythrophagocytosis. Polymerase chain reaction (PCR) analysis of formalin-fixed paraffin-embedded tissue was positive for HHV-6 and negative for Epstein-Barr virus (EBV) and cytomegalovirus (CMV). HHV-6 was also detected in the atypical lymphoid infiltrate by in-situ hybridization.

The RNA component of telomerase as a marker of biologic potential and clinical outcome in childhood neuroblastic tumors.

BACKGROUND: Telomerase is a ribonucleoprotein enzyme associated with cellular immortality that may be useful in determining the biologic potential of a tumor. Neuroblastoma (NB), ganglioneuroblastoma (GNB), and ganglioneuroma (GN) are neuroblastic tumors (NTs) that exhibit a spectrum of histologic features and are often associated with unpredictable behavior and clinical outcome. METHODS: The authors investigated the expression of the RNA component of human telomerase (hTR) by in situ hybridization in 32 cases of NTs (including 24 NBs, 4 GNBs, and 4 GNs), using [35S]-UTP labeled single stranded sense and antisense RNA probes. Eight NBs were early stage, 12 NBs were advanced stage, and 4 NBs were Stage IVS, a widely metastatic variant associated with an excellent clinical prognosis. Four NBs had N-myc amplification. In addition, the authors compared a proliferation marker, MIB-1, with hTR expression in a subset of tumors. RESULTS: Thirty of 32 NTs expressed hTR, with expression varying from weak (1+) to intense (4+). Most advanced stage NBs (9 of 12) and only 2 of 8 early stage NBs had moderate to intense (2 to 4-) expression of hTR. The remaining early stage tumors (6 of 8) and 3 of 12 advanced stage NBs had absent or weak expression of hTR (0 to 1+). There was no disease progression in any of the patients with absent or weak expression of hTR. In contrast, 8 tumors (from 7 patients) with moderate to intense expression of hTR in the tumor sections had adverse clinical outcomes, including recurrence, persistent disease, or death. hTR expression in all the Stage IVS tumors was weak, despite the fact that the patients had widely metastatic disease at presentation. The mean hTR score of 3.1 for NBs associated with an adverse outcome (n = 8) was significantly different from the mean hTR score of 1.3 for NBs associated with a favorable outcome (n = 16), P < 0.001. hTR expression in the GNB/GNs was limited to the ganglion cells only; Schwann cells were negative for hTR expression. Stage IVS tumors, which are associated with an excellent outcome, had high MIB-1 but weak hTR expression, indicating that the latter may be a better discriminator of true biologic potential and that hTR levels do not always correlate with cell proliferation. CONCLUSIONS: Increased hTR expression may reflect the potential for aggressive behavior within the spectrum of NTs; conversely, down-regulation of hTR may be useful in identifying subsets with limited capacity for progression and a favorable prognosis.

Atherosis revisited: current concepts on the pathophysiology of implantation site disorders.

There are two distinct histological manifestations of impaired placental implantation in humans--incomplete trophoblastic vascular invasion and atherosis. Both have been described to occur in pregnancies affected by a variety of disorders such as preeclampsia, fetal growth restriction, systemic lupus erythematosus, and diabetes. Our purpose was to integrate recent developments in the understanding of implantation site disorders into a pathophysiological scenario that interrelates these placentation disorders and associated pregnancy complications. Sources were identified from a MEDLINE search of English-language articles published from 1966 to 1997. Additional sources were identified from references cited in relevant reports. We selected articles relating to the following topics: atherosis, implantation site disorders, trophoblastic invasion, preeclampsia, fetal growth restriction, implantation site development, atherosclerosis, and endothelial activation-damage. A contemporary version of normal placentation, including vascular adaptation, was reviewed with comments on normal trophoblastic differentiation and vascular invasion. Specific abnormalities of the implantation site, including atherosis and incomplete trophoblastic invasion, were discussed in the context of placental site hypoperfusion and the association with pregnancy complications. It was concluded that atherosis and incomplete trophoblastic invasion may be both a consequence and a cause of placental site hypoperfusion resulting in the development of preeclampsia and a variety of other pregnancy disorders.

Epidural analgesia and intrapartum fever: placental findings.

OBJECTIVE: To assess whether epidural analgesia is associated with fever, independent of maternal infection, by evaluating the relationship between epidural analgesia and inflammation of the placenta. METHODS: Placentas collected prospectively from women with singleton gestations, who delivered 6 hours or more after membrane rupture, were evaluated systematically for histologic inflammation by an investigator blinded to all clinical information. Maternal and neonatal markers of infection were assessed in the cohorts who did and did not receive epidural analgesia. RESULTS: One hundred forty-nine consecutive placentas were analyzed, and 80 (54%) of these women received epidural analgesia. On univariate analysis, significant differences between epidural and no epidural groups were found with respect to maternal fever 38C or greater (46% versus 26%, P = .01), placenta inflammation (61% versus 36%, P = .002), and length of labor (11.8 hours versus 9.6 hours, P = .03). The combination of maternal fever plus placental inflammation was significantly more common in the epidural group (35% versus 17% P = .02). However, maternal fever in the absence of supporting evidence of infection, in the form of placental inflammation, was not increased after epidural analgesia (11% versus 9%, P = .61). CONCLUSION: Epidural analgesia is associated with intrapartum fever, but only in the presence of placental inflammation. This suggests that the fever reported with epidural analgesia is due to infection rather than the analgesia itself.

Molecular abnormalities associated with secretory carcinomas of the breast.

Secretory carcinomas (SCAs) represent a unique histological variant of invasive breast carcinomas, occurring predominantly in patients younger than 30 years of age. Data from limited series have shown SCAs to have a favorable prognosis in patients younger than 20 years of age, whereas the clinical course tends to parallel the more common in filtrating ductal carcinomas (IDCs) in patients older than 20 years. There are no reports on the molecular abnormalities associated with this unusual tumor. Microdissected archival formalin-fixed tissue from 10 SCAs collected from 2 institutions were used to determine the frequencies of allelic loss at 13 chromosomal regions with 19 microsatellite markers, using multiplex polymerase chain reaction (PCR)-based techniques. The results of loss of heterozygosity (LOH) and microsatellite alterations (MAs) analyses were compared with 20 cases of IDCs. P53 gene mutation analysis was also performed on the 10 SCAs using single-strand conformation polymorphism (SSCP) analysis, followed by sequencing of abnormal bands. LOH at multiple regions of chromosome 3p were the most common abnormality in both SCAs (55%) and IDCs (50%), followed by LOH at 17q21 (BRCA1 locus), 13q14 (retinoblastoma gene locus), and 8p21-23. No significant differences were seen in the frequencies of LOH at any chromosomal region except for 17p13 (p53 gene locus), where allelic losses were absent in SCAs, but evident in 46% of IDCs (P < .05). The 2 histological entities were similar in the fractional regional loss (FRL) index (0.26 v 0.24), fractional allelic loss (FAL) index (0.23 v 0.27), as well as in the frequency of MAs (0.015 v 0.005), P > .05. P53 gene missense mutation (G:C::A:T) was detected in 1 of 10(10%) SCAs. Based on the considerable similarities in the molecular abnormalities associated with both tumors, the formation of secondary lumina in both the in situ and the invasive components, as well as suggestions from limited series that the clinical behavior in adult patients parallels that of IDCs, SCA most likely reflects a secretory variant of IDCs.

Epstein-Barr virus polymerase chain reaction and serology in pediatric post-transplant lymphoproliferative disorder: three-year experience.

To assess whether the semiquantitative peripheral blood Epstein-Barr virus (EBV) polymerase chain reaction (PCR) test correlates with post-transplant lymphoproliferative disorder (LPD), we compiled the results of the test done over a 3-year period ending July 1997. Six hundred seventy-six tests were done on 185 patients. Four hundred-thirty tests (63%) were negative, 167 (25%) were weak positive, 67 (10%) were moderate positive, and 12 (2%) were strong positive. Twelve of the patients developed a lymphoproliferative disorder (LPD) during this time. The EBV PCR tests proximate to the diagnosis of LPD in the 12 patients with EBV-positive LPD were 6 strong positive, 5 moderate positive, 1 weak positive. No patient with LPD had a negative result at diagnosis. Stated another way, 6/12 (50%) of strong-positive PCR tests, 5/67 (7%) moderate-positive tests, and 1/167 (.6%) of weak-positive tests correlated with LPD. Serologic evaluation for EBV done on 7 patients at the time of LPD showed low serologic responses in 5 of the 7 patients. The EBV PCR temporally associated with the serology indicated moderate to large viral burdens. In each patient evaluated serially, the EBV PCR test rose before the diagnosis of LPD and fell with treatment for the disorder. In conclusion, the EBV PCR test may be used as an adjunct to the diagnosis of patients with LPD and may be used to monitor response to therapy for the disorder.

Polymerase chain reaction amplification of archival material for Epstein-Barr virus, cytomegalovirus, human herpesvirus 6, and parvovirus B19 in children with bone marrow hemophagocytosis.

Bone marrow hemophagocytosis may occur as an incidental finding, or it may be a manifestation of a systemic and potentially lethal disorder. When systemic, the proliferation is termed hemophagocytic lymphohistiocytosis (HLH), a clinicopathologic entity characterized by a widespread proliferation of benign hemophagocytic histiocytes, fever, pancytopenia, deranged liver function, and frequently coagulopathy and hepatosplenomegaly. A variety of infectious agents, including Epstein-Barr virus (EBV), cytomegalovirus (CMV), human herpesvirus 6 (HHV6), and parvovirus B19 (PVB19), have been associated with HLH, but the relative frequency of each using one technique has not been evaluated. In addition, infectious causes of incidental bone marrow hemophagocytosis, not occurring in the setting of HLH, have not been evaluated. Review of bone marrow reports from bone marrow examinations done between December 1986 and June 1997 showed that 20 children aged 2 months to 15 years had bone marrow examinations that indicated hemophagocytosis. Archival materials from 19 patients were successfully retrieved, and DNA was extracted from archived unstained coverslips with subsequent polymerase chain reaction for EBV, CMV, HHV6, and PVB19 genomic DNA. DNA extracted from 16 bone marrow specimens of age-matched children was used as negative controls. Eleven of the 19 patients fulfilled the clinical and pathological criteria for HLH; the remaining eight patients had isolated hemophagocytosis without a systemic presentation. Viral DNA was detected in 8 of 11 patients with HLH but in none of eight patients with isolated hemophagocytosis. EBV was present in five of the bone marrows, followed in frequency by HHV6, CMV, and PVB19. Infection with more than one agent was present in three patients. Only one control patient was positive for HHV6 DNA; the remaining control patients were negative for all viruses. Viral infection, detected by PCR analysis of bone marrow, is a common finding in patients with HLH but not in patients with isolated bone marrow hemophagocytosis. This technique may provide another marker to aid in the diagnosis of HLH and suggests a different cause of hemophagocytosis occurring in patients with and without HLH.

Expression of the RNA component of telomerase during human development and differentiation.

We used a radioactive in situ method to study expression of the RNA component of human telomerase (hTR) during normal human development and differentiation using archival tissues. In embryonic tissues, the highest and most uniform expression was present in undifferentiated neuroepithelium. Expression was stronger in immature epithelium than in accompanying immature mesenchyme. Differentiation of most tissues was accompanied by decreased or absent expression. Except for testis and adrenal, the adult pattern of expression was present by the 10th postnatal week. In adult tissues, high expression was present in the testis (primary spermatocytes and Sertoli cells), moderate expression was present in lymphoid follicles (germinal centers), and weak expression was present in epithelia (regenerative cells) but was absent in the nervous system and mesenchymal derived tissues. Expression in adult tissues was predominantly limited to dividing cells, although certain differentiated postmitotic cells expressed the hTR. Our studies demonstrate the complex interrelationship of hTR expression with human development, differentiation, and cell division.

Expression of the RNA component of telomerase in Wilms tumor and nephrogenic rest recapitulates renal embryogenesis.

Telomerase is a ribonucleoprotein enzyme associated with cellular immortality and has been detected in the vast majority of adult tumors. Wilms tumor is a histologically diverse embryonal malignancy of childhood, and the histological features of Wilms tumor and its precursor lesion, the nephrogenic rest, recapitulate the components of normal renal embryogenesis. Both the epithelial and the stromal components of Wilms tumor arise by differentiation of primitive mesodermal blastema. We compared expression of the RNA component of human telomerase (hTR) in normal developing kidneys, Wilms tumors, and nephrogenic rests and correlated expression of hTR with cell proliferation. Using a radioactive in situ hybridization method, we examined archival material from 17 Wilms tumors (including nine with nephrogenic rests), four therapeutically aborted embryos (37 to 56 days), three fetuses on whom autopsies had been performed, and one neonate for expression of hTR. Proliferative index was measured by immunohistochemical staining for MIB1. In the embryonic kidney, Wilms tumors, and nephrogenic rests, the patterns of hTR expression were similar: expression was usually maximal within the immature epithelial elements followed by the poorly differentiated blastema, but was weak or absent in the immature stroma. Mature tubules, glomeruli, and stroma were negative for hTR expression, as were differentiated heterologous elements present in post-therapy Wilms tumors. There was only a partial relationship between proliferative index and hTR expression. In the embryonic kidney, Wilms tumors, and nephrogenic rests, blastema had the highest proliferative index, whereas the indices were significantly lower in the immature epithelium and stroma. The proliferative index in mature and heterologous elements was low or zero. Thus, the pattern of hTR expression in Wilms tumor and its precursor lesion recapitulates embryogenesis precisely and may represent that aspect of the persistent fetal phenotype which predisposes to the development of malignancy.