Seroepidemiology of Toxoplasma in a coastal region of Haiti: multiplex bead assay detection of immunoglobulin G antibodies that recognize the SAG2A antigen.

Toxoplasma gondii is a globally distributed parasitic protozoan that infects most warm-blooded animals. We incorporated a bead coupled with recombinant SAG2A protein into our Neglected Tropical Disease (NTD) multiplex bead assay (MBA) panel and used it to determine Toxoplasma infection rates in two studies in Haiti. In a longitudinal cohort study of children aged 0-11 years, the infection rate varied with age reaching a maximum of 0·131 infections/year in children aged 3 years [95% confidence interval (CI) 0·065-0·204]. The median time to seroconversion was estimated to be 9·7 years (95% CI 7·6-∞). In a cross-sectional, community-wide survey of residents of all ages, we determined an overall seroprevalence of 28·2%. The seroprevalence age curve from the cross-sectional study also suggested that the force of infection varied with age and peaked at 0·057 infections/year (95% CI 0·033-0·080) at age 2·6 years. Integration of the Toxoplasma MBA into NTD surveys may allow for better estimates of the potential burden of congenital toxoplasmosis in underserved regions.

Ultrafast strain-induced current in a GaAs Schottky diode.

Picosecond acoustic pulses generated by femtosecond laser excitation of a metal film induce a transient current with subnanosecond rise time in a GaAs/Au Schottky diode. The signal consists of components due to the strain pulse crossing the edge of the depletion layer in the GaAs and also the GaAs/Au interface. A theoretical model is presented for the former and is shown to be in very good agreement with the experiment.

Modelling the long-acting administration of anti-tuberculosis agents using PBPK: a proof of concept study.

SETTING: Anti-tuberculosis formulations necessitate uninterrupted treatment to cure tuberculosis (TB), but are characterised by suboptimal adherence, which jeopardises therapeutic efficacy. Long-acting injectable (LAI) formulations or implants could address these associated issues. OBJECTIVE: niazid, rifapentine, bedaquiline and delamanid-in adults for treatment for latent tuberculous infection (LTBI). DESIGN: PBPK models were developed and qualified against available clinical data by integrating drug physicochemical properties and in vitro and population pharmacokinetic data into a mechanistic description of drug distribution. Combinations of optimal dose and release rates were simulated such that plasma concentrations were maintained over the epidemiological cut-off or minimum inhibitory concentration for the dosing interval. RESULTS: The PBPK model identified 1500 mg of delamanid and 250 mg of rifapentine as sufficient doses for monthly intramuscular administration, if a formulation or device can deliver the required release kinetics of 0.001-0.0025 h-1 and 0.0015-0.0025 h-1, respectively. Bedaquiline and isoniazid would require weekly to biweekly intramuscular dosing. CONCLUSION: We identified the theoretical doses and release rates of LAI anti-tuberculosis formulations. Such a strategy could ease the problem of suboptimal adherence provided the associated technological complexities for LTBI treatment are addressed.

Proliferative responsiveness of lymphocytes from Cryptosporidium parvum-exposed mice to two separate antigen fractions from oocysts.

We assessed lymphoproliferative responsiveness of lymphocytes from the spleen and lymph nodes of inbred neonatal SWR/J H-2q mice at various times postinoculation (PI) using Cryptosporidium parvum oocysts. The lymphocytes were cultured in vitro with a water-soluble (SO) and a water-insoluble (IN) antigen fraction. The IN fraction was prepared by solubilizing particulates, the sediment obtained after centrifuging disrupted oocysts, in urea. Both fractions were characterized using silver stain and enzyme-linked immunoelectrotransfer blot (EITB) with hyperimmune rabbit anti-oocyst serum, monoclonal antibody specific to a 23-kD antigen, and serum from patients with symptoms of cryptosporidiosis. The EITB showed that the antigens in the IN fraction differed both quantitatively and qualitatively from those in the SO fraction. Lymphocytes from lymph nodes of exposed mice cultured with the SO fraction exhibited a significant (P < 0.05) and antigen-specific response compared with those from unexposed mice at days 10, 19, 22, and 28 PI. The response to the IN fraction of lymphocytes from lymph nodes of exposed mice was not as consistent as that to the SO fraction but showed a significant (P < 0.05) and antigen-specific response at days 10 and 19 PI. No significant response occurred when splenic lymphocytes were cultured with SO or IN fractions. These results show that lymphocytes from lymph nodes of mice exposed to Cryptosporidium parvum oocysts proliferate when cultured in vitro with soluble or particulate antigens prepared from oocysts.

Enzyme-linked immunoelectrotransfer blot analysis of a cryptosporidiosis outbreak on a United States Coast Guard cutter.

Symptoms consistent with an outbreak of cryptosporidiosis (diarrhea, vomiting, nausea, and abdominal cramps) occurred on a U.S. Coast Guard cutter within 0-18 days after the cutter filled its tanks with Milwaukee, Wisconsin city water in March 1993. At three-weeks postdocking (PD), the suspected water was removed, and serum samples and stool specimens were collected from 47 of the 58 crew members, as well as questionnaire data on their water consumption and symptoms aboard the cutter. At 10-weeks PD and/or at 28-weeks PD, additional serum specimens were collected. Intensitometric data from enzyme-linked immunoelectrotransfer blot (EITB) were obtained on IgA responses to a 17-kD antigen group, IgM responses to a 27-kD antigen group, and IgG responses to 27-, 17-, and 15-kD antigen groups extracted from oocysts. In addition, IgG responses to crude oocyst antigens were obtained by ELISA. Based on reported symptoms, EITB results, and stool examination, the crew members were classified as confirmed (10), probable (10), suspected (22), and noncases (16). Of the 10 confirmed cases (all symptomatic) and the 10 probable cases (eight symptomatic) whose stools were positive and negative, respectively, for Cryptosporidium oocysts by microscopy, all showed changes in EITB intensities to the antigen groups and were considered EITB positive. The remaining 38 crew members, 22 suspected cases (all symptomatic), and 16 noncases (all asymptomatic), if tested, had negative stool examinations and were considered EITB negative. Of the 10 confirmed cases, only four showed a significant change in IgG responses (P < 0.05) between three-weeks PD and follow-up serum specimens by ELISA. Crew members considered confirmed cases consumed significantly more water (P < or = 0.005) aboard the cutter than noncases. Crew members considered EITB positive consumed more water (P < or = 0.04) than crew members considered EITB negative while there was no significant difference in water consumption (P > or = 0.19) between crew members considered ELISA positive and ELISA negative. Using the EITB, the observation of changes in intensity of IgA responses to the 17-kD antigen group, IgM responses to the 27-kD antigen group, and IgG responses to the 27- 17-, and 15-kD antigen groups from C. parvum oocysts between acute and convalescent serum specimens appears useful for immunodiagnosis of Cryptosporidium infection and for prospective epidemiologic studies designed to monitor infection risk.

Quantification of Cryptosporidium parvum oocysts in mouse fecal specimens using immunomagnetic particles and two-color flow cytometry.

Although single-color flow cytometry has been shown to be more sensitive than fluorescence microscopy for the quantification of Cryptosporidium parvum oocysts, this method has not been optimized. Monoclonal antibody OW50, specific to the cell wall of oocysts, was conjugated to superparamagnetic particles, to fluorescein isothiocyanate, and to r-phycoerythrin. The oocysts were then double stained with the fluorochrome-labeled OW50 and were placed in tubes with known numbers of highly fluorescent polystyrene beads, allowing quantification of the oocysts without dependence on acquired sample volume by flow cytometry. Data from 2-color flow cytometry using logical gating of the oocysts and beads showed a linear relationship between dilutions of a purified oocyst suspension and the mean numbers of oocysts detected (r2 = 1.00). An average of 15 purified oocysts/ml were counted in a dilution with a theoretical concentration of 12 oocysts/ml. Known numbers of purified oocysts were seeded into normal mouse fecal specimens, captured by OW50-labeled immunomagnetic particles, eluted with 5% potassium dichromate at low pH, and double stained with fluorochrome-labeled OW50. By flow cytometry, the mean recovery was 43.1% (+/-8.3%), and as few as 133 oocysts were detected. The captured and eluted oocysts were infective in neonatal BALB/c mice. This 2-color flow cytometry method, used in conjunction with the capture and elution of oocysts by and from immunomagnetic particles, provides a powerful tool for not only the quantification and purification of C. parvum oocysts from different sources but also for the characterization of oocysts in vitro and in vivo.

Human serologic response to subcellular antigens of Trichomonas vaginalis.

Trichomonas vaginalis organisms were processed by differential centrifugation to yield defined subcellular fractions. The various fractions were processed by methods to enhance solubility of membranes and other components. The soluble materials were analyzed for immunogenicity by a quantitative kinetic enzyme-linked immunosorbent assay (k-ELISA) and the enzyme-linked immunoelectrotransfer blot (EITB) technique using human patient serum. The principal antibodies in the human serum were directed toward cytosol components, not against membrane components, although all fractions contained multiple antigenic moieties.

Cross-sensitivity and the anticonvulsant hypersensitivity syndrome.

The anticonvulsant hypersensitivity syndrome is a rare complication that occurs with the use of antiepileptic medications. Although phenytoin is the most common culprit, carbamazepine and phenobarbital are known to cause a similar reaction. A familial occurrence has been reported. We present a case of the anticonvulsant hypersensitivity syndrome to emphasize the importance of recognizing the multiple clinical components of the syndrome and to raise awareness of the cross-sensitivity among anticonvulsants metabolized via arene oxide metabolites.

A case of Morgagni hernia presenting as pneumonia.

Morgagni-type diaphragmatic hernias are rare. The overwhelming majority are discovered in children who usually present with pneumonia or sepsis. We report an unusual case of a 57-yr-old woman with a Morgagni hernia presenting with pulmonary symptoms. Complicating the clinical picture, the pneumonia delayed the definitive diagnosis until a lateral chest X-ray study revealed loops of bowel in the right lower lung fields. It is important to entertain abdominal etiologies in the differential diagnosis of a thoracic density.

Growth counseling: A dialogue with Howard Clinebell.

This interview describes an emerging tenor in pastoral psychology, growth counseling. Philosophically cultivated by the Human Potentials Movement, this school of counseling has genetic components in biblical theology, as well as intrapsychic and interpersonal psychotherapy. Church-related issues are also linked, especially crisis intervention models for the laity and the pastoral counselor's unique vantage for ministry. In addition to these characteristics, the "dialogue" underscores two other concerns many health care professionals share: (1) a deemphasis of psychopathology via a renewed emphasis of the human "growth drive"; and (2) the therapeutic complementarity of affirmation vis-à-vis empathic confrontation.

"On the margins": A dialogue with Andrew Greeley.

This dialogue is between two priests who share common interests from different perspectives. One is an Episcopalian and a psychoanalytic psychotherapist. The other is a Roman Catholic and a sociologist widely known for his controversial novels and political commentaries. Their conversation primarily focuses on the latter's ministry-especially his investigations into paranormal experiences and his use of fiction as a homiletical avenue. They also discuss: Christian atheism; the Resurrection as a metaphor; Real Presence and liturgical sensibility; contemporary ecumenical trends; celibacy and tenures of active ministry; sexual equality and population control; religious addiction; and examples of the mythic impact of cinema.

Internment and ministry: A dialogue with Joseph Kitagawa.

This dialogue presents a profile of the late Joseph Kitagawa-a renowned scholar of the history of religions (Religionswissenschaft). It focuses on comparative religion and philosophy, as well as several other important issues related to his distinguished career as an Episcopal priest and dean of the Divinity School of the University of Chicago. They are: his experience of American concentration camps during World War II; Christian atheism and new theological models; concepts of time in Oriental and Occidental faiths; depth-psychology and contemporary ministry; and Paul Tillich's significance for the pastoral counseling movement.

Karl menninger: A centennial tribute.

This tribute primarily focuses on Karl Menninger's literary skills as a preacher. His last two books,Sparks and Whatever Became of Sin? are used as examples of what Reinhold Niebuhr called "vital prophetic Christianity." They clearly illustrate Dr. Menninger's homiletical style. These evaluations are augmented by personal conversations with him during which he strongly encouraged pastoral counselors to refocus their attention on the sermon as a basic resource for prevention and hope.

Homogamous and heterogamous marriages.

This paper explores two marital constructs set forth by Peter Giovacchini. The first is based on a symbiotic reenactment in which the investment of both partners is tenacious and reciprocal, an attachment which Giovacchini refers to as a "character object" relationship. It represents intrapsychic homogramy. In the second construct, this deep form of attraction is absent and the dyadic bond is superficial, frequently transitory. The latter couples do not require an elementary, intrapsychic bond but do share particular defensive traits or symptoms. Thus these unions are termed "symptom object" relationships and are characterologically heterogamous. By means of a group case study approach, this distinction was statistically supported. Furthermore, it was found that homogamous marriages stay in treatment longer, maintain a lower divorce rate, and respond best to individual psychoanalytic psychotherapy. Heterogamous marriages, by contrast, show a higher divorce rate and tend to leave therapy prior to termination. The research also suggests that the initial treatment of choice for this type of marriage may well be conjoint or group psychotherapy.

A fast electrophoretic isoenzyme technique for the identification of invasive and non-invasive Entamoeba histolytica and "E. histolytica-like" organisms.

Cellulose acetate electrophoresis (CAE) was used to separate glucosephosphate isomerase, hexokinase, malic enzyme, and phosphoglucomutase extracted from invasive and non-invasive Entamoeba histolytica and "E. histolytica-like" organisms. Each of these morphologically similar organisms possessed a unique CAE isoenzyme profile that can be used as an aid in their identification. The CAE technique used to obtain these isoenzyme profiles is rapid, simple, and economical, and it requires neither specialized training nor elaborate equipment.

Analysis of antigens from membrane and soluble fractions of Entamoeba histolytica.

Axenic cultures of Entamoeba histolytica strains HK-9, HM-1, and Rahman were fractionated to provide plasma membranes, internal, vesiculated membranes, and a soluble cytosol. Each particulate fraction was solubilized and all fractions were analyzed by techniques designed to demonstrate molecular complexity and serologic reactivity. The cytosol contained more antigenic moieties than either membrane fraction; however, the antigens associated with the membranes had very high reactivity and lower nonspecific activity than the cytosol.

Demonstration of species-specific and cross-reactive components of the adult microsomal antigens from Schistosoma mansoni and S. japonicum (MAMA and JAMA).

Analysis of human serum reactivities to the Schistosoma mansoni adult microsomal antigens (MAMA) showed that S. japonicum and S. haematobium infection sera, as a rule, did not react as well to MAMA as did the homologous S. mansoni infection sera. The degree of species specificity, although not absolute, was quite pronounced. Purification of the corresponding microsomal antigens from S. japonicum adults (JAMA) and subsequent assays with both homologous and heterologous infection sera show a distinct and reciprocating species specificity between S. mansoni and S. japonicum microsomal antigens. The specificities of these antigens were quantitated by k-ELISA. Qualitative analysis of active antigenic components for both JAMA and MAMA involved assay by the "Western blot" or enzyme-linked immunoelectrotransfer blot (EITB). The EITB patterns of both antigens, after resolution by SDS-PAGE, show species-specific reactive bands at the 16,000 to 35,000 m.w. region. S. japonicum-specific antigens are located at the 18,000 to 35,000 m.w. region whereas S. mansoni-specific antigens were associated with m.w. components of 16,000 to 29,000. High m.w. antigen components (greater than 40,000) of both JAMA and MAMA are recognized by both heterologous and homologous infection sera and are thus not species specific. The demonstration of the clear separation of species-specific antigen bands of JAMA and MAMA by physical size offers a unique opportunity to isolate and characterize the species specificities of antibody-antigen reactions in these parasitic infections.

Isoenzyme comparison of axenic Giardia lamblia strains.

We obtained isoenzyme patterns by polyacrylamide gradient gel electrophoresis (PGGE) of water-soluble protein fractions prepared from trophozoites of 11 axenic G. lamblia strains. The strains were isolated from animals and humans (both symptomatic and asymptomatic) from various geographic locations. Isoenzymes were also separated by isoelectric focusing. Of 12 enzymes attempted, eight exhibited well-defined and reproducible isoenzyme patterns by PGGE, based on which the strains were grouped into four zymodemes. Although the 11 strains were grouped into four zymodemes based on PGGE, no correlation between zymodeme and the known characteristics of the strains existed. Thus, a high degree of characteristic sharing appears to occur among genetically different G. lamblia strains.