Evaluation of the proficiency of trained non-laboratory health staffs and laboratory technicians using a rapid and simple HIV antibody test

In Cambodia, nearly half of pregnant women attend antenatal care (ANC), which is an entry point of services for prevention of mother-to-child transmission of HIV (PMTCT). However, most of ANC services are provided in health centres or fields, where laboratory services by technicians are not available. In this study, those voluntary confidential counselling and testing (VCCT) counsellors involved in PMTCT were trained by experienced laboratory technicians in our centre on HIV testing using Determine (Abbot Laboratories) HIV1/2 test kits through a half-day training course, which consisted of use of a pipette, how to process whole blood samples, and how to read test result. The trained counsellors were midwives working for ANC and delivery ward in our centre without any experience on laboratory works. The objective of this study was to assess the feasibility of the training by evaluating the proficiency of the trained non-laboratory staffs. The trained counsellors withdrew blood sample after pre-test counselling following ANC, and performed the rapid test. Laboratory technicians routinely did the same test and returned reports of the test results to counsellors. Reports by the counsellors and the laboratory technicians were compared, and discordant reports in two groups were re-tested with the same rapid test kit using the same blood sample. Cause of discordance was detected in discussion with both groups. Of 563 blood samples tested by six trained VCCT counsellors and three laboratory technicians, 11 samples (2.0%) were reported positive in each group, however four discordant reports (0.7%) between the groups were observed, in which two positive reports and two negative reports by the counsellors were negative and positive by the laboratory technicians, respectively. Further investigation confirmed that all the reports by the counsellors were correct, and that human error in writing reports in the laboratory was a cause of these discordant reports. These findings lead us the conclusion that the half-day training using the rapid and simple test was feasible for non-laboratory staffs to attain enough proficiency to implement VCCT services for PMTCT in resource-limited settings, and that human error was more likely to occur in laboratory before giving reports to counsellors.     

The prevalence of IgE antibody reactivity against the alkaline serine protease major allergen of Penicillium chrysogenum increases with the age of asthmatic patients.

BACKGROUND: Penicillium species are prevalent airborne fungi. However, the prevalence of allergic sensitization to Penicillium antigens and the true impact of these ubiquitous fungi on atopic respiratory disorders remain to be determined. OBJECTIVE: The purpose of this study was to analyze the prevalence of immunoglobulin (Ig)E and IgG antibodies against Penicillium chrysogenum (Pen ch 13), the alkaline serine protease major allergen of P. chrysogenum, in asthmatic patients of different age groups. METHODS: Pen ch 13 was purified from a culture medium of P. chrysogenum. The reactivity of IgE and IgG antibodies to Pen ch 13 in the serum samples of 212 asthmatic patients was analyzed by immunoblotting methods. RESULTS: Sixty-nine (33%) of the 212 sera analyzed showed IgE and/or IgG immunoblot reactivity to Pen ch 13. Significant differences in the prevalence of IgE and/or IgG antibody reactivity to Pen ch 13 were found among eight different age groups of 212 asthmatic patients. The frequency of IgE-binding reactivity to Pen ch 13 increased significantly with the age of the patients. It was 7% for the group less than 10 years old and 42% for the group older than 70 years old. In addition, a significant difference between the prevalence of IgE (7%) and IgG (33%) antibodies against Pen ch 13 in the group aged 10 or less was also found. CONCLUSIONS: Our study demonstrates that IgE and IgG antibodies specific for Pen ch 13 were detected in approximately one-third of the 212 asthmatic patients analyzed. Our results suggest that allergic sensitization to Pen ch 13, and possibly to other airborne Penicillium species, is more common in older asthmatic patients.     

Immunohistochemical localization of parathyroid hormone-related protein in parathyroid adenoma and hyperplasia

Parathyroid hormone-related protein (PTHrP) is invoked as the cause of humoral hypercalcaemia of malignancy (HHM); it is contained in the keratinocyte layer of normal skin; and there is evidence that is is produced by fetal parathyroids. Antibodies against synthetic PTHrP peptides have been raised in rabbits and sheep. This immunohistochemical study has found that primary parathyroid adenomata and hyperplastic glands from patients with chronic renal failure stain positively with antisera against PTHrP(1-34) and PTHrP(50-69). Primary hyperplastic glands are negative. No staining with anti-PTHrP(106-141) antiserum could be detected immunohistochemically in any of the parathyroid adenomata or hyperplasia.     

Preparation of a recombinant cDNA library from poly(A+) RNA of the Alzheimer brain. Identification and characterization of a cDNA copy encoding a glial-specific protein

Studies were undertaken to assess the extent to which messenger RNA prepared from the postmortem Alzheimer's disease (AD) brain can be used for the successful preparation of a recombinant cDNA library. Initial experiments focused on the glial-specific marker glial fibrillary acidic protein (GFAP) since GFAP expression appeared to be a model for further studies on mRNAs that may continue to be expressed at high levels in the vicinity of lesioned sites in the AD brain. An AD cDNA library, prepared in the lambda gt11 expression vector system contained GFAP-specific recombinants. One of these was sequenced and the insert was shown to exhibit 88% homology with the similar sequence from mouse GFAP. As established by Northern blots, the size of the GFAP mRNA prepared from the routinely acquired postmortem AD cortex, approximately 2.7 kb, was the same as from a neurologically normal control brain. These results agree with earlier studies on GFAP mRNA from fresh mouse brain. The results demonstrate that in the postmortem AD brain, astroglial-specific mRNA remains sufficiently stable for molecular genetic analysis and may serve as a useful model for examining the genetic expression of mRNAs that may be related to the molecular pathogenesis and the etiology of AD.     

An autopsy-proved case of AIDS in Taiwan

The first case of AIDS positively identified in a non-foreigner in Taiwan was a 25-year-old unmarried male who had practiced homosexuality for ten years. The patient began to have abdominal pain accompanied with loose stools and weight loss in June 1985, followed by fever, cough, headache, dizziness, and loss of memory. Facial hyperpigmentation and extensive oroesophageal candidiasis were noted. Laboratory studies showed severe lymphopenia with a reversed T-helper to T-suppressor ratio, cutaneous anergy and polyclonal gammopathy. Human immunodeficiency virus (HIV) antibodies were positive by ELISA and Western blot, and the virus was isolated from the blood. At autopsy, disseminated cytomegalovirus infection, extensive CNS toxoplasmosis and early lesions of Kaposi's sarcoma were demonstrated. The detection of HIV in the adrenal medulla supports the consensus that the virus is neurotropic.     

Identification of carmine allergens among three carmine allergy patients

BACKGROUND: There have been several reports of carmine allergy; however, identification of the responsible carmine allergens has not been widely documented. METHODS: Three female patients presented with a history of anaphylaxis and/or urticaria/angioedema after ingestion of carmine-containing foods. All three patients had 4+ skin prick tests to carmine. Among them, two patients were confirmed to have carmine allergy by blinded, placebo-controlled food challenges to carmine. SDS-PAGE of cochineal insects and carmine, immunoblotting for IgE antibody with sera from all three patients, and immunoblotting inhibition with carmine were performed. RESULTS: SDS PAGE of minced cochineal insects revealed several protein bands of 23-88 kDa. Several of these bands were variably recognized by our three patients' sera, and this reactivity was inhibited by carmine. Although no protein bands could be visualized on SDS-PAGE of carmine in Coomassie brilliant blue staining, three protein bands were recognized by two of the three patients' serum. CONCLUSIONS: These results suggest that commercial carmine retains protein-aceous material from the source insects. These insect-derived proteins (possibly complexed with carminic acid) are responsible for IgE-mediated carmine allergy. Patient reactivity to these proteins may vary.     

Effects of lesions of the histaminergic tuberomammillary nucleus on spontaneous sleep in rats

STUDY OBJECTIVES: Extensive evidence suggests that histaminergic neurons promote wakefulness. Histaminergic neurons are found exclusively in the tuberomammillary nucleus (TMN), and electrolytic lesions of the posterior hypothalamus, where the TMN resides, produce intense hypersomnolence. However, electrolytic lesions disrupt fibers of passage, and the effects of fiber-sparing, cell-specific TMN lesions on sleep and wakefulness are unknown. Hence, we placed cell-specific lesions in the TMN to determine its role in spontaneous wakefulness. DESIGN: TMN neurons in rats are relatively resistant to excitotoxins. Hence, we ablated them using saporin conjugated to hypocretin 2, which ablates hypocretin receptor-bearing neurons such as TMN neurons. One to 2 weeks after bilateral injections of Hcrt2-SAP into Sprague-Dawley rats, we correlated loss of TMN neurons with changes in sleep. SETTING: N/A PARTICIPANTS: N/A INTERVENTIONS: N/A MEASUREMENTS AND RESULTS: Four days after injections with hypocretin-2-saporin, the number of TMN neurons was markedly decreased, and most were lost after 12 days, as determined by immunohistochemistry for adenosine deaminase, a marker of TMN neurons. Nearby nonhistaminergic neurons were similarly ablated. Rats with an average 82.5% loss of TMN cells (determined 2 weeks after injection) did not have marked changes in total sleep amounts compared to saline-treated rats 1 or 2 weeks following the injection, except for a slight decrease in rapid eye movement sleep during the lights-on period for the first week only. The percentage of remaining TMN neurons positively correlated with the average duration of wake bouts during the lights-off period. CONCLUSION: The absence of gross changes in sleep after extensive loss of histaminergic neurons suggests that this system is not critical for spontaneous wakefulness.     

Gelatin-chondroitin-hyaluronan tri-copolymer scaffold for cartilage tissue engineering

The mechanism by which the cell synthesizes and secretes extracellular matrix (ECM) and is, in turn, regulated by the ECM is termed dynamic reciprocity. The aim of the present work was to produce a gelatin/chondoitin-6-sulfate/hyaluronan tri-copolymer to mimic natural cartilage matrix for use as a scaffold for cartilage tissue engineering. The scaffold produced had a uniform pore size of about 180 microm and adequate porosity of 75%. Porcine chondrocytes were seeded onto the tri-copolymer scaffold and cultured in Petri dishes or spinner flasks for 2, 3, 4, or 5 weeks. Chondrocytes were uniformly distributed in the scaffold in the spinner flask cultures, but less so in the Petri dish cultures. Secretion of ECM was found under histology examination. In spinner flask cultures, chondrocytes retained their phenotype for at least 5 weeks, as shown immunohistochemically, and synthesized type II collagen. These results show that gelatin/chondroitin sulfate/hyaluronan tri-copolymer has potential for use as a cartilage tissue engineering scaffold.     

The effect of antigen and mode of immunization on the allotypic distribution of enhanceable plaque-forming antibody

The relation between the genotypic control and phenotypic expression of antibody formation and between gene dose and product concentration depends on and is modified by antigen-mediated selection and by antigen-induced cell division. This dependence was studied in terms of allotypic specificities of rabbit light chain as markers and with different antigens and. regimens of immunization. The number of enhanceable plaque-forming cells of the same allotype was measured in the spleens of rabbits, homozygous and heterozygous at the A_b locus. A significant departure from a simple gene-dose relationship was observed. The regular preponderance of one allotype over another (“pecking order”: A4>A6>A5>A9) was confirmed. The preponderance in A⁴/A⁵ animals was found to persist whether the allotype ratio of enhanceable plaques was tested after one, two or ten injections with SRBC, after immunization with chemically modified SRBC or with DNP-HGG. There was no significant difference in the cross-reactivity of A4 and AS plaque-forming SRBC antibody. The distribution of allotype ratios of responding A⁴/A⁵ animals changed with prolonged immunization from trimodal to bimodal and finally approached unimodality. After two injections with SRBC, the incidence of individual heterozygotes, making a monoallotypic enhanceable plaque response, was greatest among animals with allotypes from the extremes of the pecking order (i.e. A⁴/A⁹). We can account for our observations and for the distribution of allotype ratios in the response to strong and to weak antigen on the basis of the following assumptions:

• I a small number of receptor-carrying precursors of antibody-forming cells is involved in the response to one cr two injections with antigen;
• II the specificity spectrum for antigens which evoke a heterogeneous response is the same for plaque-forming antibodies of different allotypic specificity (A4 or A5);
• III in heterozygotes, the ratio of receptors with different allotypic specificities is different from 1 and is related to the distance in the pecking order; the greater the distance, the greater the difference from 1;
• IV there is continuous recruitment from precursor cells during prolonged immunization.