Study of the optimum level of electrode placement for the evaluation of absolute lung resistivity with the Mk3.5 EIT system.

Inter-subject variability has caused the majority of previous electrical impedance tomography (EIT) techniques to focus on the derivation of relative or difference measures of in vivo tissue resistivity. Implicit in these techniques is the requirement for a reference or previously defined data set. This study assesses the accuracy and optimum electrode placement strategy for a recently developed method which estimates an absolute value of organ resistivity without recourse to a reference data set. Since this measurement of tissue resistivity is absolute, in Ohm metres, it should be possible to use EIT measurements for the objective diagnosis of lung diseases such as pulmonary oedema and emphysema. However, the stability and reproducibility of the method have not yet been investigated fully. To investigate these problems, this study used a Sheffield Mk3.5 system which was configured to operate with eight measurement electrodes. As a result of this study, the absolute resistivity measurement was found to be insensitive to the electrode level between 4 and 5 cm above the xiphoid process. The level of the electrode plane was varied between 2 cm and 7 cm above the xiphoid process. Absolute lung resistivity in 18 normal subjects (age 22.6 +/- 4.9, height 169.1 +/- 5.7 cm, weight 60.6 +/- 4.5 kg, body mass index 21.2 +/- 1.6: mean +/- standard deviation) was measured during both normal and deep breathing for 1 min. Three sets of measurements were made over a period of several days on each of nine of the normal male subjects. No significant differences in absolute lung resistivity were found, either during normal tidal breathing between the electrode levels of 4 and 5 cm (9.3 +/- 2.4 Omega m, 9.6 +/- 1.9 Omega m at 4 and 5 cm, respectively: mean +/- standard deviation) or during deep breathing between the electrode levels of 4 and 5 cm (10.9 +/- 2.9 Omega m and 11.1 +/- 2.3 Omega m, respectively: mean +/- standard deviation). However, the differences in absolute lung resistivity between normal and deep tidal breathing at the same electrode level are significant. No significant difference was found in the coefficient of variation between the electrode levels of 4 and 5 cm (9.5 +/- 3.6%, 8.5 +/- 3.2% at 4 and 5 cm, respectively: mean +/- standard deviation in individual subjects). Therefore, the electrode levels of 4 and 5 cm above the xiphoid process showed reasonable reliability in the measurement of absolute lung resistivity both among individuals and over time.

Alleviation of myocardial ischemia after Kawasaki disease by heparin and exercise therapy.

BACKGROUND: Heparin promotes angiogenesis. We evaluated the effects of combined treatment with heparin and exercise on myocardial ischemia in the chronic stage of Kawasaki disease. METHODS AND RESULTS: This study was conducted in 7 patients (aged 6 to 19 years) who had a totally occluded coronary artery and stress-induced myocardial ischemia in the collateral-dependent areas. Twice-daily exercise using a bicycle ergometer was performed with increments of 0.5 W/kg every 3 minutes up to maximal exertion for 10 days. Heparin, which immediately increased circulating hepatocyte growth factor, was given intravenously 10 minutes before each exercise period. Newly developed myocardial infarction, ventricular tachyarrhythmia, anginal attack, or hemorrhagic complication was not observed in any patient. Dipyridamole-loading single photon emission computed tomography documented improved myocardial perfusion in the collateral-dependent areas and a significant reduction in total defect scores in all patients after the completion of 20 sessions (P=0.01). In control patients who did not receive the heparin-exercise therapy, however, stress defect scores remained unchanged (n=1) or increased (n=2) during follow-up. Computerized quantitative coronary angiography provided evidence that the heparin-exercise therapy increased the diameter of the occluded artery to which collaterals terminated (P=0.001) but not that of the reference artery with which collaterals were not connected (P=0.96). CONCLUSIONS: The findings suggest that a series of heparin and exercise treatments over 10 days may have a dramatic effect on the alleviation of myocardial ischemia in collateral-dependent regions. This may be a safe, noninvasive revascularization therapy for patients with coronary artery occlusion in the chronic stage of Kawasaki disease.

Magnetic resonance imaging of heterotaxia in infants.

OBJECTIVES: This study assessed the usefulness and safety of magnetic resonance imaging (MRI) for systematically diagnosing heterotaxia in infants. BACKGROUND: Although it is important to diagnose and treat infants with heterotaxia, which is associated with viscerobronchial cardiovascular anomalies, systematic diagnosis of these anomalies by a single imaging technique is difficult. METHODS: Twenty patients with heterotaxia were evaluated. The infants ranged in age from 21 days to 12 months (average 5.2 months, average body weight 4.3 kg). Electrocardiographically gated MRI was performed by spin echo imaging techniques operating at 0.5 tesla. RESULTS: In all 20 patients, MRI results were sufficient to evaluate these anomalies without serious complications. In 17 patients, neither a spleen nor splenules were detected, but in 3 patients, a polymorphous spleen was visualized. In all 20 patients, bronchial anatomies were clearly visualized (bilateral eparterial bronchi in 14 patients, bilateral hyparterial bronchi in 2 and normal bronchial patterns in 4). Additionally, in a comparison of 149 observations of cardiovascular anatomy by MRI with those by angiography, discrepancies were found in only 10 observations (6.7%). CONCLUSIONS: Magnetic resonance imaging was found to be safe and very useful for the systematic diagnosis of heterotaxia in infants.

Dramatic decrease of circulating levels of monocyte chemoattractant protein-1 in Kawasaki disease after gamma globulin treatment.

Kawasaki disease (KD) is a systemic vasculitis preferentially affecting coronary arteries. Extensive monocytes/macrophages infiltrate in the vascular lesions, implying the involvement of a chemotactic cytokine in their recruitment. We investigated the role of monocyte chemoattractant protein-1 (MCP-1, also termed monocyte chemotactic and activating factor) in KD. In the immunohistochemical studies using the cardiac tissues of patients with fatal KD, MCP-1 but not interleukin (IL) -8 or macrophage inflammatory protein-1alpha was localized at the extracellular matrix associated with mononuclear cellular infiltration. The sites of MCP-1 expression correlated with the distribution of the acute inflammation, including early coronary vasculitis. In prospectively studied patients with KD, circulating levels of MCP-1, IL-8, tumor necrosis factor alpha (TNF-alpha), and IL-1alpha were elevated in 73, 77, 57, and 0% of samples before gamma globulin (GG) treatment (400 mg/kg x 5 days = total 2 g/kg), respectively, compared with respective control values. GG treatment correlated with a rapid decrease in the circulating levels of MCP-1 (P = 0.001) but not IL-8 (P = 0.19) or TNF-alpha (P = 0.33). In the sensitive Western blotting, MCP-1 bound to GG. Furthermore, GG inhibited the MCP-1-induced Ca2+ influx in a human monocytic cell line in vitro. These findings suggest a role of MCP-1 in KD, and indicate that GG treatment may block MCP-1 activity, thus alleviating KD vasculitis.

Molecular and functional properties of cytochrome c from adult Ascaris suum muscle.

Mitochondrial cytochrome c was isolated at high purity from adult Ascaris suum muscle and its molecular properties were investigated. The molecular weight of A. suum cytochrome c was determined to be 13,119 by electrospray ionization mass spectrometry. The oxidation-reduction potential of nematode cytochrome c was measured to be +248 mV; this value is comparable to those for cytochrome c from mammalian sources. The A. suum cytochrome c, like bovine heart cytochrome c, showed biphasic kinetics against bovine heart cytochrome c oxidase. Comparative kinetic studies revealed species-specificity in the reaction between cytochrome c and cytochrome c oxidase from A. suum and bovine sources. The cytochrome c content in mitochondria was highest at the second larval stage, in which the respiratory chain is the most aerobic among various developmental stages of A. suum. These data clearly show that adult A. suum cytochrome c, as isolated, is a bona fide substrate for cytochrome c oxidase in the aerobic respiratory chain of second-stage larvae.

Vascular endothelial growth factor in acute Kawasaki disease.

Vascular endothelial growth factor (VEGF), also known as vascular permeability factor, is an important regulator of angiogenesis and blood vessel permeability. Kawasaki disease (KD) is characterized by systemic vasculitis with increased vascular permeability, implying a possible role of VEGF in KD. To elucidate the involvement of VEGF in the pathogenesis of KD, we investigated 30 patients with acute KD, comparing the time course of plasma VEGF levels (n = 123) with clinical symptoms and laboratory findings. Compared with control values, the peak levels of plasma VEGF were significantly elevated (38+/-26 vs 244+/-248 pg/ml, p <0.001). The VEGF levels at the appearance of skin rash and/or edema of hands and feet were also elevated to 176+/-163 pg/ml (p <0.001). In 7 patients (23%), the plasma VEGF levels remained increased after the resolution of the skin rash and peripheral edema. The VEGF levels were independent of gamma globulin therapy and levels of serum albumin and C-reactive protein. We also measured the plasma levels of transforming growth factor-beta1 (TGF-beta1) and tumor necrosis factor alpha, both of which can upregulate VEGF in vitro. The plasma levels of VEGF were highly correlated with those of TGF-beta1 (n = 63, r = 0.73, p <0.001) but not with those of tumor necrosis factor alpha. These findings suggest that the production of VEGF is increased and may be upregulated by TGF-beta1 in acute KD. VEGF may be involved in the hyperpermeability of local blood vessels in acute KD.

Occurrence of a community with high morbidity associated with Schistosoma mansoni infection regardless of low infection intensity in north-east Brazil.

To establish the relationship between schistosome-associated morbidity and infection intensity in northeast Brazil, a parasitological and ultrasonographical study was carried out on 484 inhabitants of 4 villages (I, II, III and IV) in São Lourenço da Mata, Pernambuco, Brazil, where schistosomiasis is endemic. Quantitative stool examination using Knight's method demonstrated a high prevalence and moderate intensity of Schistosoma mansoni infection, and also that the subjects in village IV had a significantly lower prevalence and intensity of infection than those of the other villages. By ultrasonography, periportal fibrosis (PPF) and splenomegaly were found in 52% of the 299 infected subjects and 66% of the 146 infected subjects aged over 16 years old, respectively; 32% and 31% of the 299 infected subjects had abnormally high values of total bile acid (TBA) and alkaline phosphatase (ALP) activity, respectively. Liver and spleen size, PPF, and serum level of TBA and ALP were not correlated with infection intensity. There was no significant difference in the morbidity assessed by liver and spleen size, PPF, and serum analysis between the subjects in village IV and the other villages. These findings suggest the occurrence of a community with high morbidity associated with schistosomiasis regardless of low infection intensity.

Ultrastructure of acute glomerular injury in IgA nephritis.

In the ultrastructure of an acute glomerular injury in two cases of IgA nephritis (Berger's disease), the tissue damage was characterized by intravascular coagulation and an influx of fibrin-like materials into the Bowman's space forming focal and local exudative disorganizing lesion. It is supposed that this lesion correlates with the segmental fibrinoid necrosis of light microscopic expression and could be the initial event resulting in small crescents and/or local adhesive lesions of IgA nephritis.

Renal thrombotic microangiopathy in a patient with rheumatoid arthritis and antiphospholipid syndrome: successful treatment with cyclophosphamide pulse therapy and anticoagulant.

A female patient with a history of migraines and chorea developed polyarthralgia at age 24 and was diagnosed with rheumatoid arthritis. In 1991 she was hospitalized because of impaired renal function and hypertension. Examination revealed thrombocytopenia and the presence of lupus anticoagulant. Antinuclear antibody was weakly positive, but anti-DNA antibody was negative, and no decrease in leukocyte count or complement level was observed. Rheumatoid arthritis with antiphospholipid syndrome was diagnosed. Renal biopsy showed renal thrombotic microangiopathy. This renal lesion was considered to be associated with antiphospholipid syndrome. Cyclophosphamide pulse therapy and anticoagulation therapy decreased proteinuria and improved renal function.

Cerebello-oculo-hepato-renal syndrome with possible mitochondrial dysfunction.

Bilateral retinal dysfunction with optic atrophy was evident in a 26-year-old man along with renal, hepatic and cardiac dysfunction. MRI showed undersized cerebellar vermis. Blood lactate and pyruvate were high, indicating possible mitochondrial dysfunction. In biopsied biceps muscle, some ragged red fibers were identified. In five usually congenital or inherited syndromes, Dandy-Walker, Joubert, Arima, Dekaban and COACH, the symptoms such as hypoplasia or aplasia of the cerebellar vermis with multiple ocular and systemic disorders serve as the basis for differential diagnosis. The present case showed numerous symptomatic similarities and a few specific differences with Arima, Dekaban and COACH syndromes. These three syndromes and the present case were thus given a single designation, cerebello-oculo-hepato-renal syndrome, although the present case was an adult patient with sporadic onset. Some systemic disorders not included in cerebello-oculo-hepato-renal syndrome were also noted in our case and may possibly be explained by mitochondrial dysfunction, as indicated by blood pyruvate and lactate levels and the presence of ragged red fibers in biopsied biceps muscle. The relationship between cerebello-oculo-hepato-renal syndromes and mitochondrial dysfunction is discussed.

[Non-cholera vibrios in enterobacteriologic routine]. / Víbrios não coléricos na rotina enterobacteriológica.

Of 3250 diarrheal stools received for microbiologic diagnosis at a private clinical laboratory in Recife, Brazil, strains of Vibrio were isolated from 55 (1.7%). The study was carried out from May 1989 through May 1991. For recovering Vibrio, fecal samples were enriched in alkaline peptone water supplemented with 2% NaCl and subcultured on thiosulfate-citrate-bile salts-sucrose agar (TCBS). Of the recovered species, V. parahaemolyticus was most commonly found (24 strains), followed by V. furnissii (15 strains), V. cholerae non-01 (6 strains), V. alginolyticus (4 strains), V. fluvialis (2 strains), and Vibrio sp. (1 strain). The low isolation rate of Vibrio raises doubts about the cost-effectiveness of the use of TCBS in the routine enterobacteriologic workup of clinical laboratories.

[Human gastroenteritis associated with Vibrio parahaemolyticus in Recife, Brazil]. / Gastroenteritis humanas associadas a Vibrio parahaemolyticus no Recife, Brasil.

A study was carried out on the occurrence of Vibrio parahaemolyticus in 1,100 diarrheal feces, routinely sent to a private clinical laboratory for microbiologic diagnosis, in Recife. V. parahaemolyticus was isolated from 14 (1.3%) fecal samples. However, if we considered only the specimens from adult patients, the isolation rate of V. parahaemolyticus rose to 7.1%. In most cases (92.86%), V. parahaemolyticus was the only enteropathogen recognized. Among the isolates, seven K antigen serovars were demonstrated, and three were untypable. Only two human isolates, both ureolytic, did not produce the thermostable direct hemolysin. We concluded that V. parahaemolyticus is an important cause of sea food linked diarrhea among adults in Recife.

Isolation of urease-positive Vibrio parahaemolyticus from diarrheal patients in northeast Brazil.

Of 21 human fecal strains of Vibrio parahaemolyticus, isolated on the Northeast Coast of Brazil, eight (38%) were urease positive. Most of these strains, in contrast to the urease-negative ones, did not produce the hemolysin responsible for the Kanagawa phenomenon.

Prevalence and pathogenicity of Entamoeba histolytica in three different regions of Pernambuco, northeast Brazil.

Parasitological examinations were carried out on 663 individuals of three different cities of Pernambuco State, Northeastern Brazil: Recife, Palmares and Bodocó. The population from a drought area of Pernambuco State, Bodocó, was investigated for amoebiasis and compared with Recife, metropolitan city (about 1.3 million of inhabitants) and another inland community, Palmares, located inside of the sugar-cane plantation region of the State. No evidence of invasive strains of E. histolytica were found in these inhabitants, provided that the isolated zymodemes I, III, IV, VIII, IX, X, XVII and XVIII are recognized as nonpathogenic strains of E. histolytica. Furthermore, the prevalence of intestinal helminths and other protozoan infections showed that these individuals are infected by other agents responsible for diarrhoeal diseases.

Epidemiological survey of Trypanosoma cruzi infection in north-eastern Brazil using different diagnostic methods.

A survey of the prevalence of Trypanosoma cruzi infection was carried out in Oitis, a small community in the State of Piaui, Brazil. Two hundred and sixty five individuals were screened by microscopic examination, hemoculture, indirect immunofluorescence (IFA), enzyme-linked immunosorbent assay (ELISA), and competitive enzyme-linked immunosorbent assay (C-ELISA) using the monoclonal antibody TCF87 against to a 25kd T. cruzi antigen. Seropositivity was 14.3% by the IFA test, 14.7% by ELISA, and 13.2% by C-ELISA. The C-ELISA using the TCF87 monoclonal antibody seems to be applicable in serodiagnosis of Chagas' disease.

Immunoelectrophoretic study on common antigens of São Lourenço da Mata and Belo Horizonte strains of Schistosoma mansoni adult worms and Biomphalaria snails.

Immunoelectrophoretic studies on common antigens were carried out by using rabbits sera immunized against São Lourenço da Mata and Belo Horizonte strains of Schistosoma mansoni adult worms and antigens of Biomphalaria glabrata pigmented (Jaboatão--PE); B. glabrata albino (Belo Horizonte--MG) and B. straminea (São Lourenço da Mata, PE). Furthermore, the reverse approach was proceeded, namely, sera anti Biomphalaria snails produced in rabbits were tested against both strains of Schistosoma adult worm antigens. The analysis of the common antigens between the SLM strains of S. mansoni adult worm and B. glabrata pigmented showed 8 to 9 precipitin bands, 3 bands with B. glabrata albino and only 1 band with B. straminea crude extracts. On the other hand, the BH strain of S. mansoni adult worm antisera produced 6 to 7 bands with B. glabrata pigmented, 5 bands with B. glabrata albino and 1 band with B. straminea antigenic extract. Biomphalaria snails crude extracts were fractionated by Sephadex G-100 column and three fractions were collected from each snail strain. The fractions were tested with anti SLM and BH strains of S. mansoni adult worm sera by immunoelectrophoresis. The common antigens fractionated from Biomphalaria snails crude extracts and those found for both strains of S. mansoni adult worm mostly existed in the first fraction and they were estimated to have molecular weight over 158,000 daltons. In our laboratory, it was found a relationship between the antigenic similarities and experimental infection rates of S. mansoni towards Biomphalaria snails so that more bands were seen with increasing infection rates of S. mansoni.

Parasitological and serological studies on amoebiasis and other intestinal parasitic infections in the rural sector around Recife, northeast Brazil.

Parasitological examinations were carried out during July to December, 1989, on 485 inhabitants of four villages in São Lourenço da Mata, 25 km northwest of Recife, Pernambuco, Brazil. Approximately 99.6% of the inhabitants were infected with at least one species of intestinal parasites. A high prevalence of Schistosoma mansoni (82.1%), hookworm (80.2%) Trichuris trichiura (69.9%), Ascaris lumbricoides (61.9%) and Entamoeba coli (36.7%) infections were demonstrated. Test tube cultivation revealed that the most common species of hookworm in this region was Necator americanus (88.4%), and also that the prevalence of Strongyloides stercoralis was 5.8%. Three hundred and thirty-four sera were serologically examined for amoebiasis by the gel diffusion precipitation test (GDP) and enzyme-linked immunosorbent assay (ELISA). No positive reaction was observed in all sera as examined by GDP, while 24 sera were positive by ELISA.

Serological studies on schistosomiasis mansoni in the northeast Brazil (I).

Sera from the patients (N = 10) with schistosomiasis mansoni of the hospital of Federal University of Pernambuco, the Schistosoma mansoni egg-positive (N = 51) and -negative (N = 452) inhabitants in Cabo City area, out-patients (N = 37) of the IMIP hospital and Japanese immigrants (N = 127) in Petrolina City area of northeast Brazil as well as Japanese healthy subjects (N = 30) were examined by serological tests including an enzyme-linked immunosorbent assay with antigens prepared from eggs (ELISA-egg) and adult worms (ELISA-adult). The ELISA with egg or adult antigen correctly identified 100% of the uninfected individuals lived in non-endemic area of schistosomiasis. Moreover, when examined cross-reactivity of our ELISA with sera isolated from 78 subjects infected with various intestinal parasitic infections, only one of these sera reacted with the egg and adult antigens. On the examination of 51 sera from the egg-positive subjects, the ELISA-egg revealed the highest sensitivity (98.0%), whereas a large number of false negative reactions of ELISA-adult, Ouchterlony method using adult antigen, circumoval precipitation and immediate intradermal skin test were observed. A low sensitivity of these serologic tests except for ELISA-egg appears to be primarily due to their inability to detect antibody in the sera from egg-positive infantiles. There was no positive correlation between the absorbance values of these two types of ELISA among the sera isolated from ELISA-positive subjects. Rather, by the reactivity of these sera to egg or adult antigen, they could be divided into two subgroups; one reacted more positively with egg antigen and the other with adult antigen. Moreover, it was confirmed that the sera from young subjects (under 20 years old) appear to be highly reactive to the egg antigen than did aged ones. These data suggest that the ELISA with egg antigen, but not with the adult antigen, appears to be useful for the serological survey of schistosomiasis mansoni in the endemic area of northeast Brazil.

Health status of Indochinese refugees in Japan: statistical analyses on anemia, eosinophilia and serum alkaline phosphatase.

Detailed statistical analyses were attempted on anemia, eosinophilia and elevation in serum alkaline phosphatase in the Indochinese refugees in Japan. A high statistical correlation was found between hemoglobin concentration and hematocrit for most of the refugees except the Cambodian females. Refugees with parasitic infections, particularly hookworm infection had significantly lower values for hemoglobin concentration and hematocrit. Significant eosinophilia was observed in the refugees infected with hookworms, Strongyloides stercoralis, Rhabditis sp., Endolimax nana and/or Hymenolepis nana. However, these parasites were found in the same subpopulations more frequently than expected by chance. Elevation in serum alkaline phosphatase was observed in young Cambodian immigrants. Analyses showed that the variations of this enzyme could be well predictable by those of enzymes such as serum glutamic oxaloacetic transaminase, which are good markers for liver functions, in Cambodian immigrants, 13-24 of age, whereas no such correlation was observed in non-Cambodians of the same age group.

Survey for Trypanosoma cruzi infection in a municipality in northeast Brazil.

An epidemiological survey of Trypanosoma cruzi infection was carried out in Bodocó, located in the western part of the State of Pernambuco, Brazil. Two hundred and forty-one individuals were parasitologically and immunologically screened. Although hemoculture did not reveal the presence of parasites in the blood, the sera of 5 individuals were scored as positive by the indirect fluorescence antibody test and the enzyme-linked immunosorbent assay. Seropositivity in individuals above and below the age of 40 was 14.8 and 0.5%, respectively. These results indicate that recent infections with T. cruzi are rare in this area. However, since a T. cruzi-infected triatomid (Triatoma brasiliensis) was captured in a school classroom, this area must be considered endemic. When triatomid feces containing parasites were inoculated into a jird (mongolian gerbil), parasitemia appeared 10 days later. Immunohistochemical staining, using monoclonal antibody specific for T. cruzi, labeled organisms in jird tissues. These observations demonstrate that the jird is a suitable host for experimental T. cruzi infections and that monoclonal antibody is effective for detection of the parasite in host tissues.