Mother-to-child transmission of toxoplasmosis: risk estimates for clinical counselling

BACKGROUND

Women who acquire toxoplasmosis infection during pregnancy (in most cases detected through serological screening) require counselling about the risk of congenital infection and its clinical sequelae. Reliable estimates of risk are not currently available. We undertook an analysis of data from women referred to the toxoplasmosis reference laboratory, Lyon, France, between 1987 and 1995.

METHODS

Information was collected from clinical notes kept at the laboratory and, where necessary, from the relevant obstetrician or paediatrician via telephone. Methods were developed to derive estimates of the risk of congenital toxoplasmosis by exact duration of gestation at maternal seroconversion.

FINDINGS

We analysed obstetric and paediatric data on 603 confirmed maternal toxoplasmosis infections. At least 564 women received antiparasitic drugs according to a standard protocol. Congenital infection status was ascertained in 554 cases, and infected children were followed-up for a median of 54 months. The overall maternal-fetal transmission rate was 29% (95% CI 25-33), which masked a sharp increase in risk with duration of gestation from 6% at 13 weeks to 72% at 36 weeks. However, fetuses infected in early pregnancy were much more likely to show clinical signs of infection. These effects counterbalance, and women who seroconverted at 24-30 weeks of gestation carried the highest risk (10%) of having a congenitally infected child with early clinical signs who was thus at risk of long-term complications.

INTERPRETATION

This information will assist the clinical counselling of pregnant women diagnosed with acute toxoplasmosis and may guide individual decisions on investigative and therapeutic options. Further studies are required to determine the long-term risks of clinical symptoms and disability due to congenital toxoplasmosis.

Correction of the PNH defect by GPI-anchored protein transfer

Hemolytic anemia is a major feature of paroxysmal nocturnal hemoglobinuria (PNH). Intravascular red blood cell (RBC) destruction is caused by increased sensitivity of the abnormal erythrocyte to complement-mediated lysis, due to the GPI absence of a membrane-bound glycosylphosphatidylinositol (GPI)-linked protein, which functions as an inhibitor of reactive lysis (CD59). Both in vivo and in vitro models have suggested the feasibility of cell-to-cell transfer of GPI proteins, and patients with hemolysis could potentially benefit from transfer of CD59 to their deficient erythrocytes. We studied the ability of RBC components prepared from outdated packed RBC collections, as well as high-density lipoprotein (HDL) preparations, rich in CD55 and CD59, to promote protein transfer, as assessed by flow cytometry, immunoblotting, and susceptibility to complement-mediated lysis. By flow cytometry, CD55 and CD59 were present on RBC-derived microvesicles that stained with an antiglycophorin antibody Ab; in addition, soluble CD59 and CD55 were detected by immunoblot in soluble fractions eluated from RBC units stored for more than 35 days, but not in fresh blood. Both commercial HDL preparations and those prepared in our laboratory contained CD55 and CD59, as assayed by immunoblot. When RBC that were deficient (GPI)-anchored protein, obtained from five patients, with PNH were incubated with HDL preparations for 2 to 4 hours, there was significant transfer of both proteins to the cell surface, as demonstrated by flow cytometry. Washed RBC microvesicles, prepared by ultrasonification, also mediated transfer of GPI-linked proteins to deficient RBC. Pretreatment of microvesicles, RBC eluate preparations, and HDL with phosphatidylinositol-specific, phospholipase C, abrogated protein transfer to deficient cells, indicating that increased cell-associated CD55 and CD59 levels were related to insertion of the intact GPI moiety, rather than to simple adhesion. PNH RBC that were exposed to HDL, RBC eluate preparations, or microvesicles demonstrated decreased in vitro complement-mediated hemolysis in the Ham test. Transfer of GPI-linked proteins from soluble preparations containing CD55 and CD59 to PNH erythrocytes is feasible and may have clinical utility.

P2-proline-derived inhibitors of calpain I

The syntheses and biological activities of a series of calpain I inhibitors, derived from D- and L-Pro, are described.

Preoperative assessment criteria and patient teaching for ambulatory surgery patients

Today's trend is to have the surgical patient return to the comfort of his or her home rather than be admitted to the hospital for expensive nursing and medical care. The perioperative team must initially assess the patient's American Society of Anesthesiology status, anxiety level, food and drugs to which he or she may be allergic, and skin integrity; obtain a medical and surgical history and consent; review laboratory, electrocardiogram, and radiological results; and perform preoperative teaching (e.g., which medications to take or withhold preoperatively, when to withhold food and fluids) and postoperative teaching (e.g., catheter care, dressing changes). In addition, the nurse needs to anticipate and be prepared for medical emergencies such as airway management problems and malignant hyperthermia. The age of the patient (e.g., pediatric and geriatric age groups) and preoperative disease states and their severity also need to be recognized as they impact on the perioperative outcome. The assessment phase is one of the most important phases in the perioperative experience. Proper evaluation is the key to success for positive surgical outcomes. Given the time constraints in the ambulatory surgical setting, assessing and teaching the patient on the day of surgery is not feasible or appropriate. Reaching out to the patient a few days before surgery either in the patient's home, in the ambulatory surgery center, or by telephone is the ultimate goal.

Overexpression of the fanconi anemia group C gene (FAC) protects hematopoietic progenitors from death induced by Fas-mediated apoptosis

Fanconi anemia is a rare, inherited disorder characterized by bone marrow failure, congenital malformations, and cancer susceptibility. The group C Fanconi anemia gene, FAC, identified by expression cloning methods, encodes a protein of unknown function that may be involved in the response to apoptotic stimuli. Hematopoietic progenitor cells from Fac knock-out mice are hypersensitive to IFN-gamma, a molecule that can induce apoptosis through up-regulation of the Fas death receptor. In this study, we used FAC-overexpressing transgenic mice to examine the relationship between FAC and Fas-triggered cell death. Hematopoietic progenitors from FAC-transgenic mice were up to 10-fold less sensitive to the cytolytic effect of Fas-ligation. Our experiments implicate FAC in the regulation of apoptosis mediated by the Fas death receptor.

Development of scales to measure psychosocial care needs of children with seizures and their parents. 1

There is little research and no self-report assessment instruments available to guide nurses in the provision of psychosocial care to children with seizures and their families. Information on the development of two instruments, Report of Psychosocial Care Scale and Child Report of Psycyhosocial Care Scale, and their use in a research study to measure psychosocial care of children with new-onset seizures and their parents are presented in three parts. This first article describes development and initial testing of their psychometric properties. The second article, Part 2, "Psychosocial Care Needs of Parents of Children with New-Onset Seizures," describes results from the use of the parent scale with mothers and fathers of children with new-onset seizures. The third article, Part 3, "Psychosocial Care Needs of Children with New-Onset Seizures," reports findings from the use of the child scale with children ages 8-14 years with new-onset seizures.

Psychosocial care needs of children with new-onset seizures. 2

The Child Report of Psychosocial Care Scale was used to measure children's satisfaction with health care received, need for information and support and seizure-related concerns and fears in children with new-onset seizures. The sample of 63 children (33 girls and 30 boys), 8-14 years, completed the scale two times, 3 months and 6 months after their first seizure. Results indicated that children need the most nursing care in two areas: information related to the seizure condition, especially managing their condition, and support, in the form of talking to other children with seizures. The scale provides direction for tailored nursing interventions that will meet the specific needs of children with seizures for information and support.

Psychosocial care needs of parents of children with new-onset seizures. 3

The Parent Report of Psychosocial Care was developed to address the concerns, needs for care and satisfaction with care received of parents of children with new-onset seizures. Parents were interviewed three months and six months after their child's first seizures using the instrument. Mothers especially identified continued needs for information and support and were worried about unlikely events such as brain tumors and death. The results from this study indicate that parents' needs for information and support need to be assessed at every encounter with the health care system during the first 6 months after the child's first seizure.

An alternative synthesis of peptidyl alpha-keto-2-oxazolines

Application of Wipf's protocol to generate alpha-keto-2-oxazolines is described.

Applications of Ion Microscopy and In Situ Electron Microscopy to the Study of Electronic Materials and Devices

: We discuss the application of ion microscopy and in situ electron microscopy to the study of electronic and optical materials and devices. We demonstrate how the combination of in situ transmission electron microscopy and focused ion beam microscopy provides new avenues for the study for such structures, enabling extension of these techniques to the study of dopant distributions, nanoscale stresses, three-dimensional structural and chemical reconstruction, and real-time evolution of defect microstructure. We also discuss in situ applications of thermal, mechanical, electrical, and optical stresses during transmission electron microscopy imaging.

Transfection of interleukin-12 cDNAs into tumor cells induces cytotoxic immune responses against native tumor: implications for tumor vaccination

Interleukin-12 (IL-12) is a heterodimeric cytokine that is central to the development of T helper 1-dependent cellular immunity. Although this cytokine has potential therapeutic application as an antineoplastic agent, the systemic infusion of IL-12 has led to toxic fatalities; hence, restriction of expression of IL-12 to the microenvironment of target tumor cells has obvious appeal. In this study, we examined whether tumor cells that were liposome-transfected with IL-12 could enhance the induction of cytolytic lymphocyte immunity to the native tumor. The plasmid expression vector that we used has several useful features including replication to high copy number as an episome and a polycistronic message enabling the production of both the p35 and p40 subunits of IL-12 without alternative splicing; up to 3 ng/mL/10(6)/48 hours of IL-12 was produced following transfection. Tumor cells transfected with IL-12 were superior to untransfected cells in the induction of lymphocyte-mediated cytolysis. IL-12 transfectants induced a heterogeneous population of natural killer, lymphokine activated killer, and cytolytic T lymphocytes, the latter of which exhibited tumor-specific activity. Our studies suggest that liposome-mediated transfection of tumor cells with an episomal, high copy number plasmid vector expressing both IL-12 subunits is a promising approach to cancer vaccination, a strategy that could be implemented ex vivo in treating malignancies such as metastatic ovarian cancer.

Responsibilities of the preoperative holding area nurse

The preoperative holding area is an important, but often over-looked, area in the surgical suite. This area, however, is where the majority of surgical patients and their family members have their first direct contact with perioperative staff members. The preoperative holding area can provide the environment for calming, informative interactions that should help patients prepare for their surgical procedures. The preoperative holding area nurse's primary responsibility is to provide information and emotional support for patients and their family members, to ensure that all preoperative data have been accumulated, and to maintain patients' baseline hemodynamic statuses.

Ciprofloxacin-resistant Escherichia coli emerging in a rehabilitation medical center

A retrospective review of laboratory records from 1988 to 1996 has shown an increased rate of ciprofloxacin-resistant (cip(r)) Escherichia coli in our rehabilitation center. Resistance increased from 0.6% in 1989 to 5.9% in 1996. Of 7870 E. coli strains isolated during this period, 257 cip(r)-E. coli were recovered from 257 patients. The majority (96%) of these resistant strains were isolated from the urine samples. One hundred and twenty strains of cip(r)-E. coli were also resistant to four other fluoroquinolones. MICs ranging from 64 to 512 micrograms/mL were observed in 75% of the strains and > or = 1028 micrograms/mL in 6.4% of the strains. Resistance to ciprofloxacin was due to possible mutations in topoisomerase gyrA.

Malignant hyperthermia

Malignant hyperthermia (MH) is a medical emergency that all perioperative nurses should be prepared to handle. Patients with the inherited MH trait have a rare skeletal muscle disease that causes them to develop life-threatening hyperthermia (ie, body temperatures of 43.3 degrees C [110.0 degrees F] or higher) at the time MH-triggering agents are administered to induce general anesthesia or shortly thereafter. The incidence of MH episodes is reported to be 1 in every 12,000 pediatric anesthetic procedures and 1 in every 40,000 adult anesthetic procedures. The MH syndrome also is characterized by continuous skeletal muscle rigidity, hypermetabolism, hypercapnia, tachypnea, and tachycardia that result in cardiac arrest and death if left untreated. Perioperative staff members' knowledge of MH, the care of MH-susceptible patients, and adequate preparation for MH crises are the cornerstones of successful patient outcomes to this life-threatening syndrome.

Evidence for mediation of L-2-chloropropionic acid-induced delayed neuronal cell death by activation of a constitutive nitric oxide synthase

1. Delayed neuronal cell death elicited by excess excitatory amino acid concentrations has been strongly implicated in many neurological disorders including head trauma, stroke, motor neurone disease and Huntington's disease. We have used the neurotoxin, L-2-chloropropionic acid (L-CPA) to model cellular events in vivo leading to delayed neuronal cell loss which is confined to the cerebellar cortex and can be prevented by inhibitors of nitric oxide synthase such as NG-nitro-L-arginine methyl ester. 2. Experiments were performed to determine whether the constitutive nitric oxide synthase (NOS) or inducible form of NOS (iNOS) was responsible for the neuronal cell death. Activation of NOS was confirmed by a 39% increase in cerebellar total nitrate and nitrite concentrations in L-CPA-treated brains, as compared to controls (controls = 2.53 +/- 0.10; L-CPA treated = 3.51 +/- 0.31 nmol mg-1 protein, P < 0.01 Student's t tests, n = 6, mean +/- s.e.mean). Biochemical measurements of total NOS activity were made in homogenates of cerebellum 6 h and 48 h following L-CPA administration, times at which L-CPA concentrations are maximal in brain and a time when there is a high proportion of cerebellar granule cell death, respectively. NOS activity as measured by the amount of [3H]-arginine converted to [3H]-citrulline, did not reveal any difference between controls (rats dosed with water) and animals dosed with L-CPA at either 6 or 48 h following dosing. Furthermore the ability of three NOS inhibitors, NG-nitro-L-arginine, 7-bromo-3-nitroindazole and S-methylisothiourea to block the conversion of [3H]-citrulline to [3H]-arginine was identical at 6 and 48 h time points in control and L-CPA treated rats. 3. Quantitative autoradiography using [3H]-NG-nitro-L-arginine was used to measure the relative anatomical distribution and amount of NOS enzyme in the cerebellum of controls and L-CPA-treated rats 48 h following dosing. There was no significant alteration in the binding of [3H]-NG-nitro-L-arginine to granular and molecular layers of the cerebellum of control and L-CPA-treated rat brains. 4. Western blotting using antibodies against the inducible NOS enzyme failed to detect the protein in cerebellums of L-CPA-treated rats when measured 48 h after L-CPA dosing. 5. In conclusion, the increase in cerebellar nitrate/nitrite concentrations in L-CPA-treated rats provides further evidence for activation of NOS in the cerebellum following administration of L-CPA. The failure to demonstrate an increase in NOS activity at 6 or 48 h in L-CPA-treated rats as compared to controls suggests that the source of nitric oxide responsible for the granule cell death must originate from the constitutive NOS enzyme, probably the neuronal form which is highly enriched in the cerebellum. This hypothesis was further substantiated by Western blotting and quantitative autoradiography.

Spatial Patterns of Belonolaimus spp. Among and Within Citrus Orchards on Florida's Central Ridge

A survey was initiated to determine the incidence of Belonolaimus spp. (sting nematodes) in citrus orchards in the central ridge region of Florida, following widespread damage by these nematodes to young trees replanted after freezing weather in 1989-90. Sting nematodes were detected in 50% of 210 samples and in 64% of 84 orchards surveyed. More orchards in Polk County were infested with sting nematodes (82%) than in counties to the north (36%) or south (48%). Principal component analysis of morphometric data separated six of seven sting nematode populations in northeastern Polk County from six populations in adjacent regions. Stylet:tail ratio for nematodes in northeastern Polk County tend to be > 1.0 and were << 1.0 for all other populations. Patchiness of nematodes within an orchard was associated with stunted trees (23% smaller), reduced root mass density (25% lower), and low fruit yield (57% reduction). Soil texture did not vary among trees of different size in the orchard, but soil water potential between irrigation events was highest beneath small trees with low root mass density. Results of the survey indicate that the incidence of sting nematodes in orchards on the central ridge is much higher than previously estimated and that sting nematodes can cause substantial damage in replanted orchards. Further research is needed to evaluate the significance of sting nematode population variability and its relationship to citrus crop loss in Florida.