Mild gait abnormality and leg discomfort in a child secondary to extradural ganglioneuroma

Ganglioneuromas are benign and slow-growing tumors that most commonly originate from the sympathetic trunk. Ganglioneuromas often decrease in size and rarely require reoperation. Changes in gait or the onset of limb pain without a discernible local cause are indications for investigation of patients for possible intraspinal pathology. We report the case of a 5-year-old boy who presented with seemingly static symptoms, while the slow-growing tumor had enveloped nerve roots and caused bone destruction of the vertebrae.

Preeclampsia: what we know and what we do not know

Preeclampsia remains a major health problem for mothers and infants. Studying the entire pathophysiology of preeclampsia rather than "pregnancy-induced hypertension" has greatly expanded our knowledge of the disorder. Current thinking approaches preeclampsia as a 2 stage disorder: reduced placental perfusion usually secondary to abnormal implantation and a consequent maternal disorder characterized by endothelial dysfunction and subsequent pathophysiological changes. We know much about the 2 stages and less about their linkage. It is evident that reduced placental perfusion is not sufficient to account for the pathophysiology. Reduced perfusion and abnormal implantation occur in other conditions (intrauterine growth restriction and preterm labor) without the maternal syndrome. This leads to the hypothesis that reduced placental perfusion must interact with maternal constitutional factors to generate the systemic pathophysiology of preeclampsia. The similarities of these risk factors and metabolic alterations between preeclampsia and atherosclerosis suggest a common pathophysiology. Oxidative stress is postulated as the genesis of endothelial dysfunction in atherosclerosis. The author proposes that oxidative stress secondary to reduced placental perfusion leads to endothelial dysfunction, linking the 2 stages of the syndrome.

Proteasomal turnover of p21Cip1 does not require p21Cip1 ubiquitination

The Cdk inhibitor p21Cip1 is an unstable protein. Pharmacologic inhibition of the proteasome increases the half-life of p21 from less than 30 min to more than 2 hr and results in the accumulation of p21-ubiquitin conjugates. To determine whether ubiquitination was required for proteasomal degradation of p21, we constructed mutant versions of p21 that were not ubiquitinated in vivo. Remarkably, these mutants remained unstable and increased in abundance upon proteasome inhibition, indicating that direct ubiquitination of p21 is not necessary for its turnover by the proteasome. The frequently observed correlation between protein ubiquitination and proteasomal degradation is insufficient to conclude that ubiquitination is a prerequisite for degradation.

Differential requirement for CD80 and CD80/CD86-dependent costimulation in the lung immune response to an influenza virus infection

The CD28 costimulatory pathway is critical to T cell activation. Blockade of the interaction of CD28 with its ligands CD80 and CD86 using CTLA4-Ig has been proposed as a therapy for a number of immune-based disorders. We have used a murine model of influenza virus infection to study the role of CD28-dependent costimulation in the development of antiviral immune responses. In vivo treatment with CTLA4-Ig to block the interaction of CD28 with CD80 and CD86 reduced virus-specific cytotoxicity and IFN-gamma production by bronchoalveolar lavage fluid CD8+ T lymphocytes in vitro. It also resulted in decreased numbers of virus-specific CD8+ T lymphocytes in the bronchoalveolar lavage fluid, lung, and spleen and lowered virus-specific Ab titers. Mice treated with CTLA4-Ig were able to control and clear the virus infection, but this was delayed compared with controls. Treatment with Y100F-Ig, a mutant form of CTLA4-Ig which selectively binds to CD80 and blocks the CD28-CD80 interaction leaving CD28-CD86 binding intact, did not affect Ab production, spleen cytotoxic precursors, or clearance of virus. However, Y100F-Ig treatment had a clear effect on lung effector cell function. Secretion of IFN-gamma by bronchoalveolar lavage fluid CD8+ T lymphocytes in vitro was decreased, and the number of virus-specific CD8+ T lymphocytes in the bronchoalveolar lavage fluid and lungs of infected mice was reduced. These results indicate that CD28-dependent costimulation is important in the antiviral immune response to an influenza virus infection. The individual CD28 ligand, CD80, is important for some lung immune responses and cannot always be compensated for by CD86.

Genetic variation in Pneumocystis carinii isolates from different geographic regions: implications for transmission

To study transmission patterns of Pneumocystis carinii pneumonia (PCP) in persons with AIDS, we evaluated P. carinii isolates from patients in five U.S. cities for variation at two independent genetic loci, the mitochondrial large subunit rRNA and dihydropteroate synthase. Fourteen unique multilocus genotypes were observed in 191 isolates that were examined at both loci. Mixed infections, accounting for 17.8% of cases, were associated with primary PCP. Genotype frequency distribution patterns varied by patients' place of diagnosis but not by place of birth. Genetic variation at the two loci suggests three probable characteristics of transmission: that most cases of PCP do not result from infections acquired early in life, that infections are actively acquired from a relatively common source (humans or the environment), and that humans, while not necessarily involved in direct infection of other humans, are nevertheless important in the transmission cycle of P. carinii f. sp. hominis.

National surveillance for infection with Cryptosporidium parvum, 1995-1998: what have we learned?

OBJECTIVE

Infection with Cryptosporidium parvum generally causes a self-limiting diarrheal illness. Symptoms can, however, last for weeks and can be severe, especially in immunocompromised individuals. In 1994, the Council of State and Territorial Epidemiologists (CSTE) recommended that cryptosporidiosis be a nationally notifiable disease. Forty-seven states have made infection with C. parvum notifiable to the Centers for Disease Control and Prevention (CDC), and laboratories in the three remaining states report cases to state health departments, which may report them to the CDC. To see what the data show about patterns of infection, the authors reviewed the first four years of reports to the CDC.

METHODS

The authors analyzed reports of laboratory-confirmed cases of cryptosporidiosis for 1995-1998.

RESULTS

During 1995-1998, 11,612 laboratory-confirmed cases of cryptosporidiosis were reported to the CDC. All ages and both sexes were affected. An increase in case reporting was observed in late summer during each year of surveillance for people <20 years of age.

CONCLUSION

The first national data on laboratory-confirmed cryptosporidiosis cases, although incomplete, provide useful information on the burden of disease in the nation as well as provide baseline data for monitoring of future trends.

Invasive cytotrophoblasts manifest evidence of oxidative stress in preeclampsia

In preeclampsia, poor placental perfusion may result in maternal endothelial dysfunction, but the pathways involved are largely unknown. Candidate placental mediators include products of oxidative stress released into the maternal circulation. Xanthine oxidase has been implicated in postischemic-reperfusion injury via the generation of superoxide anion radicals (superoxide; O(2)(.-)) and hydrogen peroxide. We examined placentas and placental bed curettings and/or biopsies from preeclamptic control pregnant women to test the hypothesis that xanthine oxidase is a mediator of oxidative stress in placentas from women with preeclampsia. The expression of xanthine dehydrogenase/xanthine oxidase holoenzyme and the activity of xanthine oxidase, the isoform known to generate reactive oxygen species, were increased in a subpopulation of cytotrophoblasts of preeclamptic women. Additionally, the expression of superoxide dismutase, which would scavenge superoxide produced by xanthine oxidase, was reduced in the same cells. Furthermore, fluorescence immunostaining for nitrotyrosine, which was suggestive of superoxide-nitric oxide interactions to form peroxynitrite anion (ONOO(-)) in vivo, was increased in these cells and in villous vessels. Thus, our data indicate an increased capacity of placental cells to generate reactive oxygen species in preeclampsia.

Risk factors for community-acquired pneumonia among persons infected with human immunodeficiency virus

Two hundred eleven adults with human immunodeficiency virus (HIV) infection hospitalized for community-acquired pneumonia, including Pneumocystis carinii pneumonia (PCP; patients), and 192 matched HIV-infected hospitalized patients without pneumonia (controls) were interviewed to determine risk factors for pneumonia. Multivariate logistic regression showed that patients were less likely than controls to have used trimethoprim-sulfamethoxazole (TMP-SMZ) prophylaxis (odds ratio [OR], 0.22; 95% confidence interval [CI], 0.12-0.41) and more likely to have been hospitalized previously with pneumonia (OR, 6.25; CI, 3.40-11.5). Patients were also more likely than controls to have gardened (OR, 2.24; CI, 1.00-5.02) and to have camped or hiked (OR, 4.95; CI, 1.31-18.7), but stratified analysis by etiologic agent showed this association only for PCP. These findings reconfirm the efficacy of TMP-SMZ in preventing community-acquired pneumonia. In addition, hospitalization for pneumonia might represent a missed opportunity to encourage HIV-infected patients to enter into regular medical care and to adhere to prescribed antiretroviral and prophylaxis medications.

The preterm prediction study: effect of gestational age and cause of preterm birth on subsequent obstetric outcome. National Institute of Child Health and Human Development Maternal-Fetal Medicine Units Network

OBJECTIVE

We sought to evaluate the association between prior spontaneous preterm delivery and subsequent pregnancy outcome.

STUDY DESIGN

A total of 1711 multiparous women with singleton gestations were prospectively evaluated at 23 to 24 weeks' gestation. Prior pregnancies were coded for the presence or absence of a prior spontaneous preterm delivery. If a prior spontaneous preterm delivery had occurred, the gestation of the earliest prior delivery (13-22, 23-27, 28-34, and 35-36 weeks' gestation) was recorded. Current gestations were categorized as spontaneous preterm delivery at <28, <30, <32, <35, or <37 weeks' gestation. The risk of spontaneous preterm delivery in the current gestation was determined on the basis of the occurrence, gestational age, and cause of the earliest prior spontaneous preterm delivery.

RESULTS

The incidences of spontaneous preterm delivery before 28, 30, 32, 35, and 37 weeks' gestation were 0.8%, 1.1%, 1.9%, 5.1%, and 11.9%, respectively. Those with a prior spontaneous preterm delivery carried a 2.5-fold increase in the risk of spontaneous preterm delivery in the current gestation over those with no prior spontaneous preterm delivery (21. 7% vs 8.8%; P </=.001). Gravid women with an early prior spontaneous preterm delivery (23-27 weeks' gestation) had a higher risk of recurrent spontaneous preterm delivery (27.1% vs 8.8%; P </=.001). Prior spontaneous preterm delivery was more closely associated with subsequent early spontaneous preterm delivery at <28 weeks' gestation (relative risk, 10.6) than for spontaneous preterm delivery overall (relative risk, 2.5). An early prior spontaneous preterm delivery (23-27 weeks' gestation) was most highly associated with early spontaneous preterm delivery (<28 weeks' gestation) in the current gestation (relative risk, 22.1). The relationship between prior spontaneous preterm delivery and current outcome was not as strong for those with a very early spontaneous preterm delivery (13-22 weeks' gestation). Prior spontaneous preterm delivery caused by preterm premature rupture of the membranes and preterm labor was significantly associated with similar outcomes in the current gestation (P <.001).

CONCLUSION

Prior spontaneous preterm delivery is highly associated with recurrence in the current gestation. An early prior spontaneous preterm delivery is more predictive of recurrence and is most highly associated with subsequent early spontaneous preterm delivery.

Safety of labor epidural anesthesia for women with severe hypertensive disease. National Institute of Child Health and Human Development Maternal-Fetal Medicine Units Network

OBJECTIVE

The aim of this study was to determine whether epidural anesthesia during labor increased the frequencies of cesarean delivery, pulmonary edema, and renal failure among women with severe hypertensive disease.

STUDY DESIGN

We performed a secondary retrospective analysis of a subgroup population within a multicenter double-blind trial of low-dose aspirin therapy for women at high risk for development of preeclampsia. Subjects in whom severe hypertensive disease developed were selected. The primary outcomes were the overall frequencies of cesarean delivery among women with severe hypertensive disease who had labor with and without epidural anesthesia. Other maternal and neonatal outcomes were also compared between women who did and did not receive epidural anesthesia.

RESULTS

Among the women with severe hypertensive disease (n = 444) 327 had labor. Among the women with severe disease who had labor there was no difference in either the overall cesarean delivery rate (32.1% vs 28.0%; P =.44) or the rate of cesarean delivery for fetal distress or failure to progress (27.8% vs 22.0%; P =.26) between women who did and did not receive epidural analgesia. Women with chronic hypertension were more likely to have a cesarean delivery overall if they received epidural anesthesia, but there was otherwise no difference in the frequencies of cesarean delivery for these indications between women with and without epidural anesthesia within each of the high-risk groups. Pulmonary edema was rare and acute renal failure did not develop in any women.

CONCLUSION

Epidural anesthesia use did not increase the frequencies of cesarean delivery, pulmonary edema, and renal failure among women with severe hypertensive disease.

Biphasic stimulation of prostacyclin by endogenous nitric oxide (NO) in endothelial cells transfected with inducible NO synthase

Nitric oxide (NO) regulates prostaglandin H synthase (PGHS) activity in various cell types, but reports conflict in regard to its stimulatory versus inhibitory role. Murine lung endothelial cells infected with a retroviral vector expressing the human inducible NO synthase gene were used to prevent ambiguous effects of NO from either exogenous chemical donors or cytokine-stimulated cells. Low concentrations of endogenous NO led to a dose-dependent increase in 6-keto PGF1alpha production (p < 0.05), whereas the highest production of NO resulted in lower 6-keto PGF1alpha production. These data demonstrate a complex regulation of PGHS activity by NO that needs to be considered when proposing a physiological or pathophysiological role for NO.

Urinary cotinine concentration confirms the reduced risk of preeclampsia with tobacco exposure

OBJECTIVE

We assessed tobacco exposure in nulliparous women with preeclampsia compared with that in control subjects by measuring urinary cotinine to confirm the reduced risk of preeclampsia associated with tobacco exposure during pregnancy.

STUDY DESIGN

A case-control study group of 50 women with preeclampsia after 35 weeks of gestation and a group of 50 control subjects matched for gestational age, date of delivery, and body mass index were selected from the project database. Urine obtained on admission was assayed for cotinine. Self-reported smoking information was blinded during patient selection and laboratory assay.

RESULTS

Thirty-five patients had detectable urinary cotinine levels, 11 (22%) with preeclampsia and 24 (48%) control women. Mean cotinine concentrations among exposed women were 331 ng/mL for those with preeclampsia and 540 ng/mL for control subjects. The odds ratio of preeclampsia developing in an exposed woman was 0.31 (95% confidence interval, 0.12-0.79).

CONCLUSION

These findings, obtained by using laboratory assay, confirm the reduced risk of developing preeclampsia with tobacco exposure.

Association of pre-eclampsia with common coding sequence variations in the lipoprotein lipase gene

Marked dyslipidemia may contribute to endothelial cell dysfunction in pre-eclampsia. Carriers of N291S or D9N missense mutations in the lipoprotein lipase (LPL) gene exhibit reductions in LPL activity and are predisposed to dyslipidemia and cardiovascular disease. In Caucasians, the D9N variant is in strong linkage disequilibrium with the - 93T --> G promoter variant. A fourth LPL variant, S447X, is often associated with a beneficial lipid profile. We asked if the N291S and the combination D9N/- 93T --> G variants are more prevalent, and if the S447X variant is less prevalent, in Caucasian women with pre-eclampsia as compared with normal pregnancies. DNA amplification was followed by an allele-specific oligonucleotide ligation assay. Allele frequencies were analyzed with a chi2 table and Yates' correction. The N291S variant was identified in 11.1% of pre-eclamptics as compared with 2.9% of pregnancy controls (p = 0.008). All carriers of D9N were also carriers of - 93T --> G. The D9N/ - 93T --> G combined variant was found in 7.1% of pre-eclamptics as compared with 1.4% of pregnancy controls (p = 0.02). No individuals were carriers of both N291S and D9N/ - 93T --> G. Thus, 18.2% of pre-eclamptics had either of these LPL mutations compared with 4.3% of pregnancy controls (and 4.4% of population controls). The frequency of the S447X variant did not differ among groups. We conclude that carriers of N291S or combined D9N/ - 93T --> G mutations in the LPL gene are at substantially increased risk of pre-eclampsia.

Cullin-3 targets cyclin E for ubiquitination and controls S phase in mammalian cells

Cyclin E is an unstable protein that is degraded in a ubiquitin- and proteasome- dependent pathway. Two factors stimulate cyclin E ubiquitination in vivo: when it is free of its CDK partner, and when it is phosphorylated on threonine 380. We pursued the first of these pathways by using a two-hybrid screen to identify proteins that could bind only to free cyclin E. This resulted in the isolation of human Cul-3, a member of the cullin family of E3 ubiquitin-protein ligases. We found that Cul-3 was bound to cyclin E but not to cyclin E-Cdk2 complexes in mammalian cells, and that overexpression of Cul-3 increased ubiquitination of cyclin E but not other cyclins. Conversely, deletion of the Cul-3 gene in mice caused increased accumulation of cyclin E protein, and had cell-type-specific effects on S-phase regulation. In the extraembryonic ectoderm, in which cells undergo a standard mitotic cycle, there was a greatly increased number of cells in S phase. In the trophectoderm, in which cells go through endocycles, there was a block to entry into S phase. The SCF pathway, which targets cyclins for ubiquitination on the basis of their phosphorylation state, and the Cul-3 pathway, which selects cyclin E for ubiquitination on the basis of its assembly into CDK complexes, may be complementary ways to control cyclin abundance.

Increased umbilical cellular fibronectin concentrations are associated with a decreased prevalence of growth restriction in preeclampsia

OBJECTIVE

Cellular fibronectin (cFN), a marker of endothelial activation, is elevated in maternal and cord blood in preeclampsia. We tested whether maternal or fetal cFN is related to fetal growth restriction in preeclampsia, in the context of gestational age at delivery.

METHODS

Cellular fibronectin was measured in maternal and cord blood of 29 preeclamptic women and their infants delivered at Magee-Womens Hospital at 25-41 weeks of gestation. Relationships among maternal and cord cFN, birth weight, birth weight percentile, and ponderal index were evaluated using Pearson correlation and regression analyses controlled for gestational age.

RESULTS

Cord cFN was not significantly related to maternal cFN (r = -.34, P = .08) or gestational age (r = -.32, P = .09). The relationship of maternal cFN to each index of infant size was not significant. By contrast, higher cord cFN predicted higher birth weight, birth weight percentile, and ponderal index (P < .05).

CONCLUSION

Elevated maternal and cord cFN concentrations have been reported in pregnancy complicated by preeclampsia. This study assessed the relationship among maternal cFN, cord cFN, and indices of fetal growth in preeclampsia. Elevated cord cFN was associated with measures of better fetal growth.

Effect of stretching duration on active and passive range of motion in the lower extremity

OBJECTIVES

To investigate the effect of different durations of stretching (five or 15 seconds) on active and passive range of motion (ROM) in the lower extremity during a five week flexibility training programme.

METHOD

Twenty four university sport club members (19 men, five women), with a mean (SD) age of 20.5 (1.35) years, were randomly assigned to one of three groups (two treatment and one control). The two treatment groups participated in a static active stretching programme three times a week for a five week period, holding each stretch for a duration of either five or 15 seconds. The total amount of time spent in a stretched position was controlled. The five second group performed each stretch nine times and the 15 second group three times resulting in a total stretching time of 45 seconds for both groups for each exercise. The control group did not stretch. Active and passive ROM were determined during left hip flexion, left knee flexion, and left knee extension before and after the training programme using an inclinometer.

RESULTS

Two factor within subject analysis of variance indicated no significant difference in ROM before and after the training programme for the control group. However, significant improvements in active and passive ROM (p < 0.05) were shown in both treatment groups after the five week training programme. Two factor analysis of variance with repeated measures and post hoc analysis showed significant differences between the treatment groups and the control group for the improvements observed in active (p < 0.05) and passive (p < 0.05) ROM. The five and 15 second treatment groups did not differ from one another when ROM was assessed passively, but significant differences were apparent for active ROM, with the 15 second group showing significantly greater improvements (p < 0.05) than the five second group.

CONCLUSION

These findings suggest that holding stretches for 15 seconds, as opposed to five seconds, may result in greater improvements in active ROM. However, sustaining a stretch may not significantly affect the improvements gained in passive ROM.

Elevated oxidase and esterase levels associated with permethrin tolerance in Anopheles gambiae from Kenyan villages using permethrin-impregnated nets

The permethrin tolerance (PT) of a population of the mosquito Anopheles gambiae (Diptera: Culicidae) increased following the introduction of permethrin-impregnated nets for malaria control in certain villages near Kisumu, western Kenya. Using a biochemical test that indirectly measures oxidases associated with permethrin resistance, we found that this population had higher oxidase levels than a comparison population from villages without impregnated nets. Mosquitoes from a colony of An. gambiae selected for PT, the RSP (reduced susceptibility to permethrin) strain, were exposed to permethrin with or without the oxidase inhibitor piperonyl butoxide (PB). Significantly higher mortality rates occurred when permethrin was synergized by PB, presumably by suppression of oxidases responsible for PT. An unselected (UNS) colony of An. gambiae that was more susceptible than RSP in a permethrin-susceptibility bioassay (i.e. LT50 22 min for UNS, vs. 42min for RSP) was compared with the RSP colony for levels of oxidases and esterases. The levels of both enzymes were very significantly higher in the RSP strain (P<0.0001). We speculate that use of impregnated nets selected for higher oxidase and esterase levels in An. gambiae to metabolize permethrin acquired from the nets. Both oxidase and esterase mechanisms could confer cross-resistance to other pyrethroids.

Endogenous nitric oxide suppresses rat myometrial connexin 43 gap junction protein expression during pregnancy

Nitric oxide (NO) synthase (NOS) is active in the gravid uterus, and its activity decreases prior to the onset of parturition. We tested the hypothesis that NO helps maintain uterine quiescence by suppressing the expression of genes necessary for parturition. Pregnant rats (18 days gestation) were treated with inducible NOS (iNOS) inhibitor N-iminoethyl-L-lysine (NIL) or endothelial NOS inhibitor nitro-L-arginine methyl ester (L-NAME); 24 h later, uteri were analyzed for myometrial connexin 43 (Cx43) protein by immunoblotting and mRNA by Northern analysis. Myometrial oxytocin receptors (OTR) were measured by radioligand binding, and decidual prostaglandin H synthase (PGHS) protein by immunoblotting. Uterine NOS blockade was verified by NOS activity assay. We found that NIL, but not L-NAME, significantly increased myometrial Cx43 protein to parturitional levels with treatment at 19 but not 17 days gestation. Steady state mRNA concentrations were not changed at 24 h. NOS inhibition did not increase the concentrations of OTR, or PGHS protein, nor did it decrease maternal serum progesterone. We conclude that endogenous uterine NO from iNOS suppresses myometrial Cx43 gap junction protein expression during rat pregnancy. Although the exact mechanism is unknown, an increase of uterine wall stretch due to inhibition of relaxation could account for increased Cx43 gene transcription.

Current concepts in preeclampsia

The purpose of this article is to review recent epidemiologic and pathophysiologic findings that advance the understanding of preeclampsia for the nurse in perinatal practice. Preeclampsia is different from other hypertensive disorders of pregnancy. Risk factors for preeclampsia and recent findings regarding normal and aberrant implantation are presented. Abnormal implantation and resulting poor placental perfusion may be the impetus for endothelial changes evidenced in preeclampsia; pathophysiology is described in relation to this event. The interaction of maternal factors, reduced placental perfusion, and endothelial cell dysfunction provides an explanation for the occurrence of preeclampsia and provides a basis for nursing practice and research. Implications for nursing care for women of childbearing age before, during, or after pregnancy may include (a) preconception or post-delivery counseling to reduce modifiable risk factors such as obesity, sedentary lifestyle, or high fat intake, (b) assessment of risk factors and increased surveillance when risk factors are present, and (c) surveillance of blood pressure changes of > 30 mmHg systolic or > 15 mmHg diastolic in advance of the third trimester of pregnancy.