ABSTRACT
BACKGROUND: Bracing constitutes the mainstay treatment for mild scoliosis. The 3D reconstruction of the spine using low-dose stereoradiographic imaging (LSI) is increasingly being used to determine the true shape of the deformity and to assess the success of bracing. OBJECTIVE: The aim of the study was to validate the measurement of 3D spinopelvic parameters and vertebral rotation in the setting of bracing treatment via a reliability study conducted in adherence to the guidelines for reporting reliability and agreement studies (GRRAS). MATERIAL AND METHODS: Full spine stereoradiographs of patients with adolescent idiopathic scoliosis (AIS) who underwent Chêneau bracing were retrospectively analyzed. The 3D reconstruction was performed by two experienced operators in a blinded manner and randomized order. Rotation of every vertebra was computed in the coronal, sagittal and axial planes. Sagittal spinopelvic parameters were evaluated. All measurements were statistically compared to determine agreement of the measurement of brace correction using the intraclass correlation coefficient (ICC). RESULTS: In this study, 45 patients (81% females) aged 12.5⯱ 2 years were included. The mean absolute difference was less than 3.5° for all measured angles, less than 4â¯mm for sagittal vertical axis (SVA) and less than 1.5â¯mm for lateral pelvic shift. The ICC was high for all parameters (ICC >0.81). Despite the overall high reliability, the reliability of axial rotation was lower in the upper and middle thoracic spine and the lower lumbar spine. CONCLUSION: Brace wearing during full spine LSI acquisition does not affect spinal measurements. The LSI under bracing treatment produces reliable measurements of spinopelvic parameters as well as vertebral rotation. These reproducible 3D data enable spine surgeons to assess the true shape of the deformity, to quantify rotation of each vertebra and enhance the understanding of the efficacy of bracing treatment.
Subject(s)
Braces , Imaging, Three-Dimensional/methods , Kyphosis/diagnostic imaging , Scoliosis/diagnostic imaging , Spine/diagnostic imaging , Adolescent , Child , Female , Humans , Male , Predictive Value of Tests , Radiation Dosage , Radiographic Image Interpretation, Computer-Assisted , Radiosurgery , Reproducibility of Results , Retrospective Studies , Scoliosis/surgery , Spine/surgeryABSTRACT
The original article [1] contains a small mistake concerning the ARTIC Team members mentioned in the Acknowledgements. The team member, Rocco Salvatore Calabrò had their name presented incorrectly. This has now been corrected in the original article.
ABSTRACT
OBJECTIVE: We hypothesize that imaging findings from CT and MRI correlate better with clinical markers for assessment of disease activity in patients with the rare relapsing polychondritis (RPC) than with serological inflammatory markers. MATERIALS AND METHODS: Retrospective database search at our institution identified 28 patients (13 females; age 49.0 years±15.0 SD) with RP between September 2004 and March 2014. Institutional review board approval was obtained for this retrospective data analysis. All patients had clinically proven RPC with at least two episodes of active disease. Of those, 18 patients were examined with CT- and MRI and presented all morphologic features of RPC like bronchial/laryngeal/auricular cartilage thickness, contrast enhancement, increased T2-signal intensity. Imaging data was subsequently correlated with corresponding clinical symptoms like fever, dyspnea, stridor, uveitis, pain, hearing impairment as well as with acute-phase-inflammatory parameters like C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR). RESULTS: The clinical parameters were in good agreement with imaging findings and clinical symptoms such as tracheal wall thickening and dyspnea (r =0.65 p=0.05), joint synovitis on MRI and a higher McAdam score (r=0.84 p<0.001). No correlations were found between inflammatory laboratory markers, imaging findings and clinical features. CONCLUSION: Imaging diagnosis in RPC using CT and/or MRI delivers information about the degree of disease activity that correlates better with clinical features than unspecific inflammatory laboratory markers. Additionally, clinically unapparent cartilage involvement can be assessed adding value to the clinical diagnosis and therapy planning in this rare disease.
Subject(s)
Cartilage/diagnostic imaging , Cytokines/blood , Magnetic Resonance Imaging/methods , Polychondritis, Relapsing/blood , Polychondritis, Relapsing/diagnosis , Tomography, X-Ray Computed/methods , Adult , Aged , Aged, 80 and over , Biomarkers/blood , Cartilage/metabolism , Female , Humans , Inflammation Mediators/blood , Male , Middle Aged , Polychondritis, Relapsing/diagnostic imaging , Reproducibility of Results , Sensitivity and Specificity , Serologic Tests , Statistics as TopicABSTRACT
BACKGROUND: Sarcopenia describes the age-associated loss of muscle mass, strength and function. The aim of this study was to compare the prevalence of sarcopenia in a cohort of community dwelling elderly people living in Berlin, Germany, according to the criteria proposed by current consensus statements and to study the respective impact on self-reported physical performance. MATERIAL AND METHODS: This study included 1405 participants from the Berlin aging study II (BASE-II). The appendicular skeletal muscle mass index (SMI) was assessed with dual energy X-ray absorptiometry (DXA), muscle strength was measured by hand grip strength and the timed up and go" test (TUG) was performed as a functional parameter to reflect mobility. RESULTS: The prevalence of sarcopenia was 24.3 % in terms of reduced SMI only and considerably lower for sarcopenia with reduced grip strength (4.1 %) and sarcopenia with limited mobility (2.4 %). Only 0.6 % of the participants fulfilled all three criteria. Of the subjects with a normal SMI, 8.6 % had reduced grip strength and 5.1 % had limited mobility, whereas 1.3 % subjects fulfilled both criteria. Participants with reduced strength or function reported severe difficulties in performing physical tasks significantly more often than participants with normal or reduced SMI alone (p <0.029-p <0.0001). CONCLUSION: In BASE-II low skeletal muscle mass was much more frequent than reduced grip strength or poor function. Reduced strength and function were found to be associated with a greater impact on physical performance than reduced muscle mass. Low SMI does not seem to be a prerequisite for low strength or limitations in mobility.
Subject(s)
Geriatric Assessment/methods , Independent Living/statistics & numerical data , Muscle Weakness/diagnosis , Muscle Weakness/epidemiology , Sarcopenia/diagnosis , Sarcopenia/epidemiology , Absorptiometry, Photon/statistics & numerical data , Age Distribution , Aged , Aged, 80 and over , Berlin/epidemiology , Female , Geriatric Assessment/statistics & numerical data , Germany/epidemiology , Hand Strength , Humans , Male , Middle Aged , Muscle Weakness/classification , Prevalence , Reproducibility of Results , Risk Factors , Sarcopenia/classification , Self Report , Sensitivity and Specificity , Sex Distribution , Terminology as Topic , Walking SpeedABSTRACT
OBJECTIVES: To determine the diagnostic benefit of volume perfusion computed tomography (VPCT) at end of treatment for response assessment in lymphoma patients. METHODS: Seventy-five patients with different lymphoma subtypes were included: 50/75 patients had residual masses at end of treatment, 26/50 patients underwent VPCT at baseline and at end of treatment, and 24/50 patients only had end-of-treatment VPCTs. We evaluated the size of the main lymphoma mass, its blood flow (BF), blood volume (BV) and k-trans, calculated ratios (baseline and end of treatment) as well as sensitivity/specificity/negative (NPV)/positive predictive values (PPV). For VPCT at end of treatment, a cutoff threshold between responders and non-responders was calculated. RESULTS: For patients undergoing VPCT at baseline and end of treatment, reduction in size, BF, BV and k-trans was significant (P < 0.001). Identification of non-response was reached at: <53% reduction in size (sensitivity/specificity/accuracy/PPV/NPV of 88.89%/62.5%/80.77%/84.21%/71.43%), <15% reduction of BF (sensitivity/specificity/accuracy/PPV/NPV of 100%/37.5%/80.77%/0.26%/100%), or <45% reduction of k-trans (sensitivity/specificity/accuracy/PPV/NPV of 88.89%/75%/84.62%/88.89%/75%). In the subgroup undergoing VPCT at end of treatment, BF >18.51 ml/100 ml indicated non-responsiveness (sensitivity 92.86%, specificity 72.73%, accuracy 84%, PPV 81.25%, NPV 88.89%). CONCLUSIONS: VPCT seems adequate for assessment of lymphoma response at end of treatment. The degree of residual lymphoma perfusion at end of treatment helps to identify patients likely to remain in remission 1 year after completion of therapy. KEY POINTS: ⢠Volume perfusion computed tomography (VPCT) offers measurements for assessing tumour response. ⢠Perfusion parameter changes measured by VPCT correlate with antitumour therapy response. ⢠In lymphoma, baseline and end-of-treatment perfusion parameter ratios can predict response. ⢠Perfusion measurements after treatment identify patients likely to remain in remission.
Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Cone-Beam Computed Tomography , Drug Monitoring/methods , Lymphoma/diagnostic imaging , Lymphoma/drug therapy , Adult , Aged , Aged, 80 and over , Blood Volume , Female , Humans , Male , Middle Aged , Neoplasm, Residual , Perfusion Imaging , Prospective Studies , Salvage Therapy/methods , Sensitivity and SpecificityABSTRACT
Cardiac masses are challenging for non-invasive diagnostic procedures and therapy, respectively. In tumor patients differentiation between primary or secondary cardiac neoplasm and thrombus is a frequent and knowingly difficult task to manage. To avoid complex and unnecessary surgical diagnostic procedures non-invasive methods are in favor. For initiation of adequate therapy and evaluation of prognosis, however, early and reliable diagnosis is mandatory. So far, echocardiography and magnetic resonance imaging represent the mainstay for cardiac imaging diagnosis. Recently, the new technique of CT-based tumor volume perfusion (VPCT) measurement has advanced to a potent, reliable, and easy to perform alternative for cardiac imaging. The purpose of this study was to review the existing spectrum of diagnostic modalities for characterization of cardiac masses in an oncologic patient cohort with emphasis on their strengths and limitations and to present the benefit from using the novel technique called VPCT for this purpose.
Subject(s)
Heart Neoplasms/diagnostic imaging , Incidental Findings , Perfusion Imaging/methods , Tomography, X-Ray Computed/methods , Tumor Burden , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Reproducibility of ResultsABSTRACT
The zebra mussel Dreissena polymorpha is widely used as sentinel organism for the assessment of environmental contamination in freshwater environments. However, in the River Rhine (Germany), the D. polymorpha population is declining, whereas the closely related quagga mussel D. bugensis is found in high numbers at some sites. In the present laboratory study, D. polymorpha and D. bugensis were exposed to resuspended native sediments for ≤2 weeks. Wet sediments (<63 µm, 100 mg l(-1) dry weight) were used as surrogate suspended particulate matter to mimic one of the mussels' main uptake route for chemicals. The sediments were sampled in (1) the River Elbe in Dessau, a site known to be highly polluted with, e.g., organochlorine (OC) pesticides and (2) at a relatively unpolluted site in Havelberg in the River Havel, one of the Elbe's tributaries. Chemical analysis of persistent OC compounds (seven polychlorinated biphenyls [PCBs], DDT and its metabolites (DDX), hexachlorocylohexanes [HCHs], and hexachlorobenzene [HCB]) in soft tissue of mussels showed significantly greater values of PCBs 101, 118, 153, 138, 180, the sum of seven PCBs, and p,p'-DDD in D. bugensis compared with D. polymorpha. Fourteen days of exposure to Dessau sediment increased the concentration of p,p'-DDE and p,p'-DDD, as well as the sum of DDX, in both species compared with Havelberg sediment. Interspecific differences were less pronounced when regarding chemical concentrations with lipid content instead of dry-weight of tissue because D. bugensis had greater levels of total lipid than D. polymorpha. DNA damage in gills, as measured with the comet assay, was greater in D. bugensis compared with D. polymorpha. Simultaneously, the content of heat-shock protein (hsp70) in gills was greater in D. polymorpha than in D. bugensis. DNA damage and hsp70 were not induced by exposure time or sediment type. This study shows that D. bugensis and D. polymorpha may differ in their bioaccumulation potential of OC pesticides as well as their levels of DNA damage and hsp70. Therefore, more investigations are needed before quagga mussel can be used as alternative test organism for the zebra mussel.
Subject(s)
Dreissena/metabolism , Environmental Exposure , Geologic Sediments , Water Pollutants, Chemical/pharmacokinetics , Animals , Biomarkers , DDT/analysis , DNA Damage , Dichlorodiphenyl Dichloroethylene/analysis , Dichlorodiphenyl Dichloroethylene/pharmacokinetics , Dichlorodiphenyldichloroethane/analysis , Dichlorodiphenyldichloroethane/pharmacokinetics , Dreissena/drug effects , Environmental Monitoring/methods , Geologic Sediments/chemistry , Germany , Gills/drug effects , Gills/metabolism , HSP70 Heat-Shock Proteins/metabolism , Hexachlorobenzene/analysis , Hexachlorocyclohexane/analysis , Hydrocarbons, Chlorinated/analysis , Pesticides/analysis , Pesticides/pharmacokinetics , Pesticides/toxicity , Polychlorinated Biphenyls/analysis , Rivers , Species Specificity , Water Pollutants, Chemical/analysisABSTRACT
Plasmodium berghei were released from mouse erythrocytes by passage through a French pressure cell. The released organisms were washed and disintegrated; the soluble portion was chromatographed on a Sephadex (G-200) column. The void-volume eluate contained an erythrocyte-free plasmodial fraction which behaved as a vaccine, preventing parasitemia, anemia, and death in mice subsequently challenged with living Plasmodium berghei.
Subject(s)
Malaria/immunology , Plasmodium/isolation & purification , Vaccines/therapeutic use , Animals , Chromatography, Ion Exchange , Malaria/prevention & control , Mice , Plasmodium/immunologyABSTRACT
An outbreak of Toxoplasmosis in a colony of squirrel monkeys (Saimiri sciureus) in Israel is described. Serological, pathological, and molecular findings of monkeys, as well as rodents and pigeons from the vicinity are summarized. Seventy-nine percent (19/24) of monkeys were T. gondii seropositive at titer 1:16 whilst 4% (1/24) were also seropositive at titer 1:64 using the Modified Agglutination Test (MAT). Eighty four percent (21/25) of rats were positive at titer 1:16 and 8% (2/25) of rats were positive at titer 1:32. DNA amplification of a 529bp repeated sequence of T. gondii was detected in the liver and lungs of all monkeys tested, 6/7 in myocardial extractions and 5/6 in brain extractions. Sequence analysis of the SAG2 locus disclosed that T. gondii detected was of Type III genotype. The source of disease was thought to be contamination of feed with infective feline oocysts. As a result of this study, the implementation of a program to capture and remove resident feral cats, to discontinue the feeding of stray cats, and to control rodent populations in the park was introduced.
Subject(s)
Antibodies, Protozoan/immunology , Antigens, Protozoan/immunology , Disease Outbreaks , Saimiri/parasitology , Toxoplasma/isolation & purification , Toxoplasmosis, Animal/pathology , Agglutination Tests/veterinary , Animals , Antibodies, Protozoan/genetics , Antigens, Protozoan/genetics , Cats , Female , Genotype , Israel/epidemiology , Male , Mice , Oocysts/immunology , Parasite Egg Count/veterinary , Polymerase Chain Reaction/veterinary , Rats , Saimiri/genetics , Saimiri/immunology , Seroepidemiologic Studies , Toxoplasma/genetics , Toxoplasma/immunology , Toxoplasmosis, Animal/epidemiology , Toxoplasmosis, Animal/geneticsABSTRACT
BACKGROUND: Frailty and the metabolic Syndrome (MetS) are frequently found in old subjects and have been associated with increased risk of functional decline and dependency. Moreover, central characteristics of the MetS like inflammation, obesity and insulin resistance have been associated with the frailty syndrome. However, the relationship between MetS and frailty has not yet been studied in detail. Aim of the current analysis within the Berlin Aging Study II (BASE-II) was to explore associations between MetS and frailty taking important co-variables such as nutrition (total energy intake, dietary vitamin D intake), physical activity and vitamin D-status into account. METHODS: Complete cross-sectional data of 1,486 old participants (50.2% women, 68.7 (65.8-71.3) years) of BASE-II were analyzed. MetS was defined following the joint interim statement of the International Diabetes Federation Task Force on Epidemiology and Prevention; National Heart, Lung, and Blood Institute; American Heart Association; World Heart Federation; International Atherosclerosis Society; and International Association for the Study of Obesity in 2009. Frailty was defined according to the Fried criteria. Limitations in physical performance were assessed via questionnaire, muscle mass was measured using dual energy X-ray absorptiometry (DXA) and grip strength using a Smedley dynamometer. Adjusted regression models were calculated to assess the association between MetS and Frailty. RESULTS: MetS was prevalent in 37.6% of the study population and 31.9% were frail or prefrail according to the here calculated frailty index. In adjusted models the odds of being frail/prefrail were increased about 50% with presence of the MetS (OR1.5; 95% CI 1.2,1.9; p= 0.002). Moreover the odds of being prefrail/frail were significantly increased with low HDL-C (OR: 1.5 (95%CI: 1.0-2.3); p = 0.037); and elevated waist circumference (OR: 1.65 (95%CI: 1.1-2.3); p = 0.008). CONCLUSION: The current analysis supports an association between MetS and frailty. There are various metabolic, immune and endocrine alterations in MetS that also play a role in mechanisms underlying the frailty syndrome. To what extent cytokine alterations, inflammatory processes, vitamin D supply and hormonal changes in age and in special metabolic states as MetS influence the development of frailty should be subject of further research.
Subject(s)
Frailty/epidemiology , Metabolic Syndrome/epidemiology , Aged , Berlin/epidemiology , Cross-Sectional Studies , Female , Frail Elderly , Humans , MaleABSTRACT
A Toxoplasma gondii seroprevalence survey was conducted in poultry flocks kept under different housing systems in Israel. The seroprevalence rates were 35.4% (46/130) in battery-raised chicken egg-layers from Jerusalem which were first raised on the ground, 12.5% (19/152) in free-range chickens from various locations of the country and 9% (4/45) in turkeys from the north. However, all broilers (50) and chicken breeding stock (58) kept under high biosecurity conditions in Jerusalem were found to be T. gondii seronegative. It is concluded that high biosecurity conditions prevent contamination with oocysts by rendering premises inaccessible to cats.
ABSTRACT
PURPOSE: To retrospectively compare CT-patterns of pulmonary infiltration caused by different Influenza virus types and subtypes in immunocompetent and immunocompromised patients for possible discrimination. MATERIALS AND METHODS: Retrospective database search at our institution yielded 237 patients who were tested positive for Influenza virus type A or type B by bronchoalveolar lavage between January 2009 and April 2014. Fifty-six of these patients (female 26; male 30; median age 55.8 y, range 17-86 y; SD ± 14.4 y) underwent chest-HRCT due to a more severe clinical course of pulmonary infection. We registered all CT-findings compatible with pulmonary infection classifying them as airway predominant (tree-in-bud, centrilobular nodules, bronchial wall thickening ± peribronchial ground-glass opacity and consolidation) vs. interstitial-parenchymal predominant (bilateral, symmetrical GGO, consolidation, crazy paving and/or interlobular septal thickening). Twenty-six patients (46.4%) had follow-up CT-studies (0.78 mean, SD ± 5.8 scans). RESULTS: Thirty-six patients were immunocompromised (group I) whereas 20 patients were immunocompetent (group II). An airway-centric pattern of infection was found in 15 patients (group I) and 14 patients (group II) whereas an interstitial-parenchymal predominant pattern was found in 14 patients (group I) and 2 patients (group II). Eleven patients had a mixed pattern with no clear assignment to one group. At FU, 12 patients from group I and 3 from group II showed transitional infiltration patterns: in 10 patients from interstitial-parenchymal into airway predominant pattern and in five patients from airway predominant into interstitial-parenchymal. No significant differences in the pattern of pulmonary infection were found between different types and subtypes of Influenza viruses. CONCLUSION: Patterns of pulmonary infiltration caused by Influenza viruses do not significantly differ between immunocompetent and immunocompromised patients or between different types and subtypes of Influenza virus. One possible explanation for this could be the temporarily interchangeable character of pulmonary infiltration in this infection.
Subject(s)
Immunocompromised Host , Influenza, Human/complications , Influenza, Human/diagnostic imaging , Pneumonia, Viral/complications , Pneumonia, Viral/diagnostic imaging , Tomography, X-Ray Computed/methods , Adolescent , Adult , Aged , Aged, 80 and over , Bronchoalveolar Lavage , Female , Follow-Up Studies , Humans , Lung/diagnostic imaging , Male , Middle Aged , Retrospective Studies , Young AdultABSTRACT
Predicting the bioavailability and effects of metals in sediments is of major concern in context with sediment risk assessment. This study aimed to investigate the bioavailability and molecular effects of metals spiked into riverine sediments to zebrafish (Danio rerio) embryos. Embryos were exposed to a natural and an artificial sediment spiked with cadmium (Cd), copper (Cu), nickel (Ni) and zinc (Zn) individually or as a mixture at concentrations ranging from 150 to 3000 mg/kg dry weight (dw) over 48 h, and uptake of metals was determined. Furthermore, transcript abundances of the metallothioneins MT1 and MT2, the metal-responsive element-binding transcription factor (MTF) and the genes sod1, hsp70 and hsp90α1 were measured as indicators of metal-induced or general cellular stress. D. rerio embryos accumulated metals from sediments at concentrations up to 100 times greater than those spiked to the sediment with the greatest bioaccumulation factor (BAF) for Cu from artificial sediment (275.4 ± 41.9 (SD)). Embryos accumulated greater concentrations of all metals from artificial than from natural sediment, and accumulation was greater when embryos were exposed to individual metals than when they were exposed to the mixture. Exposure of embryos to Zn or the mixture exhibited up to 30-fold greater transcript abundances of MT1, MT2 and hsp70 compared to controls which is related to significant uptake of Zn from the sediment. Further changes in transcript abundances could not be related to a significant uptake of metals from sediments. These studies reveal that metals from spiked sediments are bioavailable to D. rerio embryos directly exposed to sediments and that the induction of specific genes can be used as biomarkers for the exposure of early life stages of zebrafish to metal-contaminated sediments.
Subject(s)
Water Pollutants, Chemical/pharmacokinetics , Animals , Cadmium/pharmacokinetics , Cadmium/toxicity , Copper/pharmacokinetics , Copper/toxicity , Gene Expression/drug effects , Geologic Sediments/chemistry , Nickel/pharmacokinetics , Nickel/toxicity , Water Pollutants, Chemical/toxicity , Zebrafish , Zebrafish Proteins/genetics , Zebrafish Proteins/metabolism , Zinc/pharmacokinetics , Zinc/toxicityABSTRACT
Sonicated red blood cells (RBC) of rats infected with Plasmodium berghei (Pb) were used to coat plastic tubes with Pb antigens. The antigen-coated tubes were employed to detect Pb antigens and antibodies, with high efficiency. Anti-Pb antibodies were estimated by treating the tubes with rabbit or rat anti-Pb sera and assaying the bound Ig with radiolabeled Staphylococcus PrA. Pb antigens were detected by their capacity to inhibit the binding of the anti-Pb antibodies. Using a rabbit-Pb serum, sonicated, infected RBC (50% parasitemia) gave detectable inhibition up to 1 : 106 dilution.
Subject(s)
Antibodies/analysis , Antigens/analysis , Malaria , Plasmodium berghei/immunology , Radioimmunoassay/methods , Animals , Erythrocytes/immunology , Erythrocytes/parasitology , Malaria/immunology , Malaria/parasitology , Rabbits , Rats , Staphylococcal Protein AABSTRACT
A highly sensitive radioimmunoassay for detection of P. falciparum antibodies and antigens is described. A partially purified P. falciparum antigen preparation is obtained from in vitro cultured parasites enriched after gelatin sedimentation by sonicating the infected red blood cells and precipitating the proteins with 50% saturated ammonium sulfate. The precipitate is dissolved in buffer, ultracentrifuged and used to coat wells of microtiter plates. Anti-P. falciparum antibodies are detected by incubating antiserum dilutions in the coated wells and detecting the bound IgG with radioiodinated staphylococcal protein A. P. falciparum antigens are detected by their ability to inhibit binding of antibodies to the coated wells. Sera of individuals with a history of P. falciparum infection contain antibodies detectable at a dilution of 1:75,000. P. falciparum RBC infected in vitro can be detected at levels of parasitemia of the order of 1 parasite or less per 10(6) RBC.
Subject(s)
Antibodies/analysis , Antigens/analysis , Malaria/diagnosis , Binding Sites, Antibody , Binding, Competitive , Erythrocytes/immunology , Erythrocytes/parasitology , Humans , Malaria/blood , Malaria/parasitology , Plasmodium falciparum/immunology , Radioimmunoassay/methodsABSTRACT
An enzyme-linked immunosorbent assay was developed for the detection of specific salivary IgA antibodies to Giardia lamblia. Among 73 infants and children in a day care center 9 asymptomatic subjects had stools positive for G. lamblia. Salivary antigiardia IgA concentrations, expressed as OD units, were higher in the 2- to 4-year-old group: 0.899 +/- 0.03 vs. 0.660 +/- 0.03 in the < 2-year old group (P < 0.001). In both groups values were higher in the infected children (1.099 +/- 0.04 vs. 0.629 +/- 0.09 in the < 2-year-old group and 1.053 +/- 0.07 vs. 0.859 +/- 0.03 in the 2- to 4-year-old group). In children infected throughout the study period, salivary antigiardia antibodies remained consistently high and in 2 children whose stools were initially negative a significant rise in OD value was observed after stools tested positive. Total salivary IgA did not differ between the two age groups and did not correlate with specific salivary antigiardia antibodies in individual subjects. The enzyme-linked immunosorbent assay for detection of specific salivary antibodies to G. lamblia can be used in the study of the mucosal immune response to the parasite, and may serve as an screening tool in monitoring the exposure of various populations to G. lamblia.
Subject(s)
Antibodies, Protozoan/analysis , Giardia lamblia/immunology , Immunoglobulin A/analysis , Saliva/immunology , Animals , Child Day Care Centers , Child, Preschool , Enzyme-Linked Immunosorbent Assay , Feces/parasitology , Giardia lamblia/isolation & purification , Humans , Infant , Sensitivity and SpecificityABSTRACT
An enzyme-linked immunosorbent assay for rapid detection of malarial antibodies and antigens was developed. Plasmodium falciparum antigen preparation, obtained from sonicated cultures of the parasite at a parasitemia of 10%-15%, was applied to cellulose filter discs in volumes of 0.1 microliter in 96-well microtiter plates. Antibodies were detected by successive incubations with: bovine serum albumin for blocking, tested serum at different dilutions, peroxidase-conjugated antihuman IgG, and the precipitable substrate 4-chloro-1-naphtol. Positive reactions appeared as blue dots on a white background which are easily read by eye. Pools of sera from patients with recent disease or from individuals with a history of malaria, contained antibodies detectable up to a dilution of 1:64,000. Negative results were obtained when normal RBC were used for dotting the filters. Normal sera showed no reaction at any antigen concentration. P. falciparum antigens were detected by their ability to inhibit the binding of antibody to the filters. RBC infected with P. falciparum in vitro can be detected at a level of 0.001% parasitemia. This report presents the feasibility of an assay for detecting malarial antibodies and antigens in blood samples which is easily applicable to field conditions.
Subject(s)
Antibodies/analysis , Antigens, Protozoan/analysis , Enzyme-Linked Immunosorbent Assay , Malaria/diagnosis , Plasmodium falciparum/immunology , Humans , Malaria/immunologyABSTRACT
Fifty-two patients with severe chloroquine resistant Plasmodium falciparum malaria were treated in a randomized double blind study with either quinine and a single dose of pyrimethamine-sulfadoxine (Fansidar) or quinine alone. Although no statistically significant differences were observed, the 25 patients who received both drugs responded faster and had a more favorable outcome (no deaths) when compared to the 27 who received quinine alone (2 deaths).
Subject(s)
Malaria/drug therapy , Pyrimethamine/administration & dosage , Quinine/therapeutic use , Sulfadoxine/administration & dosage , Sulfanilamides/administration & dosage , Clinical Trials as Topic , Double-Blind Method , Drug Combinations , Drug Therapy, Combination , Humans , Plasmodium falciparum , Pyrimethamine/therapeutic use , Quinine/administration & dosage , Random Allocation , Sulfadoxine/therapeutic useABSTRACT
A rapid and simple assay for detecting Plasmodium falciparum in human blood was developed. The assay is based on DNA-DNA spot hybridization, using radiolabeled P. falciparum DNA as a probe and finger prick blood as the assay sample. It is very sensitive, able to detect parasitemia levels of 0.0001% in 10 microliter of blood. The assay can be quantified and used to estimate parasitemia levels. Several hundred blood samples can be processed simultaneously, and the entire procedure is completed within 24 hr. This assay can be useful for epidemiological surveys, for screening of blood by blood banks and for health authorities examining immigrants and tourists coming from malaria infested areas.
Subject(s)
DNA/metabolism , Malaria/diagnosis , Nucleic Acid Hybridization , Collodion , Humans , Malaria/blood , Plasmodium falciparum/genetics , RadioimmunoassayABSTRACT
Small numbers of rat erythrocytes infected with viable P. berghei, when inoculated into susceptible rats together with hyperimmune rat serum (HIS), are fully neutralized. Serum from convalescent rats delays the onset of patency but does not neutralize. The neutralizing efficiency of HIS rises in proportion to the number of successive reinoculations of hyperimmune rats. In contrast, mice inoculated with parasites together with either HIS or normal rat serum succumbed to the disease at the same time after inoculation. Neutralization in rats occurs in vivo and is completed within 22 hours of inoculation. Much larger amounts of HIS are needed to achieve neutralization in splenectomized recipients than in intact rats. The action of HIS is dose-dependent. Thus, the degree of suppression of parasitaemia is proportional to the dose of HIS, while the mortality rate is inversely proportional to the dose. Suboptimal doses may even enhance the infection of recipient rats. The ability to produce neutralizing antibody is dissimilar in two strains of rat. Thus, the outbred Sabra strain produces neutralizing HIS, while the inbred Lewis rat is incapable of producing perceptible neutralizing antibody in our experimental model.