Hypocomplementemia associated with hepatitis C viremia in sera from voluntary blood donors

OBJECTIVES

Hepatitis C virus (HCV) infection induces extra-hepatic manifestations, most of which are considered to be mediated by circulating immune complexes. For evaluating this association in a wider perspective, complement activity was determined in sera from apparently healthy individuals, and hypocomplementemia was tested for correlation with HCV viremia.

METHODS

Sera from 10,532 voluntary blood donors were stored at 4 degrees C overnight, serially diluted 2-fold, and tested for hemolytic activity by a microtitration method and antibody to HCV (anti-HCV) by passive hemagglutination with recombinant HCV antigens of the second generation. HCV RNA was determined in sera with anti-HCV or hypocomplementemia, or both, by polymerase chain reaction with nested primers deduced from the 5'-noncoding region of the HCV genome.

RESULTS

Hypocomplementemia was detected in 53 (0.5%) of 10,532 donations and anti-HCV in 94 (0.9%). Anti-HCV was detected in 48 (91%) of the 53 sera with hypocomplementemia, more frequently than in 46 (0.44%) of 10,479 sera without (p < 0.001). Among 94 sera positive for anti-HCV, HCV RNA was detected in 45 (94%) of 48 sera with hypocomplementemia, more often than in 10 (22%) of 46 sera without (p < 0.001).

CONCLUSIONS

A close association of hypocomplementemia with HCV viremia among apparently healthy blood donors would reflect circulating immune complexes which may cause extrahepatic diseases, such as cryoglobulinemia and membranoproliferative glomerulonephritis, in some HCV carriers. The storage of sera from HCV carriers at 4 degrees C before the test would have contributed to a decreased hemolytic activity due to the cold activation of complement by cryoglobulins involving HCV.

The ACE inhibitor alacepril suppresses atherogenesis independent of serum lipids in cholesterol-fed rabbits--critical analysis with new ultrasound technique

The effects of alacepril, an angiotensin converting enzyme inhibitor, on atherogenesis were examined in rabbits fed a hypercholesterol diet. The process of atherogenesis was evaluated in vitro by high-resolution transesophageal ultrasonography (TEE phi 4 mm, 7.5 MHz), by direct histological examination and by serum lipid examination. Of the 38 subjects, 18 were designated as the control hypercholesterol group (CH) and 20 received oral alacepril at 90 mg/day (ACE) for 13-22 weeks. Three rabbits in each group died due to pneumonia. TEE enabled a clear diagnosis as either normal, early stage or late stage of atherosclerosis. The intimal-medial thickness was significantly less in the ACE group than in the CH group, but only over the middle portion of the aorta. The ACE group had a smaller area of atheromatous plaque than the CH group (atheromatous index: 37 +/- 20* and 60 +/- 30% respectively, *p < 0.02). Serum cholesterol and triglycerides were similar in the CH group (1590 +/- 653, 258 +/- 224) and the ACE group (1574 +/- 824, 303 +/- 360 respectively). In conclusion, alacepril reduced both the area of atheromatous atheroma plaque and wall hypertrophy independent of serum lipids in cholesterol-fed rabbits. In vitro miniature TEE is a dependable method for evaluating atherosclerosis in rabbits with hypercholesterolemia.

High resolution miniature trans-esophageal echocardiography is useful to evaluate atherosclerosis and the effects of alacepril in hyper-cholesterol rabbits

This study tested the efficacy of high resolution miniature transesophageal echocardiography (m-TEE; 3.5 mm-diameter probe, 7.5 MHz, axial resolution of 0.25 mm) in the evaluation of atherosclerotic lesions of the thoracic aorta rabbits exposed to a high cholesterol diet. The effects of the ACE inhibitor Alacepril (90 mg/kg) on atherosclerosis were also assessed in normotensive, high cholesterol-diet rabbits by m-TEE, both in situ and in vitro. Oral treatment with Alacepril was begun on confirmation of atherosclerosis after a three month high cholesterol diet (group AL). Ultrasound examination reliably distinguished the lesions of atherosclerosis in situ. A three month course of Alacepril treatment decreased the systolic and diastolic blood pressures by approximately 20 and 5 mmHg, produced a regression of atherosclerosis and significantly decreased the intimal plus medial thickness compared with hyperlipidemic-controls (group HC) (1.0 + 0.3 vs 1.6 + 0.4 mm, p < 0.02). The intimal surface involvement area in group AL was marginally smaller than in group HC (57 + 23 vs 76 + 23%, p = 0.06). The high dose of Alacepril in this study did not affect the serum levels of t-cholesterol, HDL-C, LDL-C, triglycerides, or apoproteins A-I and B. These results suggest that Alacepril can produce regression of atherosclerosis, without changing circulating lipoprotein or apoprotein levels. Further miniature TEE offers high repeatability and is useful both in situ and in vitro for determining changes in arterial wall thickness and the severity of atherosclerosis.

Efficacy of various commercial dentin bonding systems

OBJECTIVES

The purpose of this study was to test the bonding efficacy of fifteen commercial dentin bonding systems and also to determine the effect of various commercial dentin cleaners on bonding and dentin hardness.

METHODS

Each commercial bonding system was examined by two methods: 1) measuring the maximum contraction gap of a light-cured composite in a cylindrical dentin cavity; and 2) determine the tensile bond strength to a flat dentin surface. In addition, various commercial dentin cleansers were investigated to determine if dentin hardness was reduced after cleaning. As a control, the dentin surface was cleaned with neutralized EDTA prior to the combined application of an experimental dentin primer, a commercial bonding agent, and a commercial light-cured composite.

RESULTS

The study demonstrated that complete marginal adaptation was obtained by the experimental dentin bonding system used as the control. However, it was not possible to completely prevent gap formation with the commercial dentin bonding systems tested. A high correlation (R = 0.88) was observed between maximum contraction gap width and reduction of hardness only in the group in which the dentin was rinsed after cleaning.

SIGNIFICANCE

It is very important to combine optimal dentin cleansers, primers, and bonding agents to compensate for the polymerization contraction stress of the composite. Therefore, it was speculated that the commercial dentin bonding systems tested in this study consisted of unsuitable materials.

Statistically corrected ocean thermography

A corrected thermal imaging method for a wind-roughened water surface is proposed. This method can be applied even if the imaging system is placed at low altitudes, say on a ship or on land, as well as on an airborne platform. Such a technique is desirable from the following points of view: the surveillance of bioresources (fish), environmental assessments of a seaside industrial zone (hot waste water), and temporal complement and spatial interpolation of satellite observations of thermal images. The method is based on the analysis of optical characteristics of a model of a wind-roughened water surface, namely, the Gaussian-Joint North Sea Wave Project (JONSWAP) model, where the surface displacement obeys Gaussian distribution while its spectrum is specified by the JONSWAP wave spectral model. We present the basic temperature-correction formula and the algorithm for correction. The correction takes into account thermal emission of the water's surface, radiation of the sky reflected on the water's surface, and both absorption and emission by the atmosphere along the light path. This formula can be used for temperature correction of an infrared image of sky and random water surface. The experimental results that we obtained are encouraging.

A neurosynaptic model of state-dependent EEG wave generation in the subcortico-cortical system

A neurosynaptic model of the subcortico-cortical system is presented in order to analyze the mechanism for the generation of EEG rhythms with specific state-dependent spectral patterns. The model is based on the interaction among the infraslow, as well as basic, rhythms of the PSP's (postsynaptic potentials) trains from which CSD's (current source densities) or cortical surface potentials emerge. The model system was simulated by two trains of positive and negative cortical surface potentials within the same period, according to the thalamic clock as modulated by the infraslow rhythms of the midbrain reticular system. The simulated EEG's showed rhythmic waxing and waning sawtooth-like waves with no frequency fluctuation, but with some spectral broadband peaks at the basic repetitive frequency, as well as its harmonics.

Influence of reapportionment of daily salt intake on circadian blood pressure pattern in normotensive subjects

The aim of this study was to investigate whether there is variation in blood pressure when we reapportion the percentage of total daily salt intake consumed at each of three regular meals. The study was conducted on seven clinically healthy normotensive female subjects who, in Stages LH and DH, consumed two-thirds of the normal daily salt intake (12 g/day) at lunchtime or at dinnertime, respectively. The total daily amounts of nutrients and dietary salt were similar in Stage-R (regulated salt intake), Stage-LH (a high-salt intake at lunchtime), and Stage-DH (a high-salt intake at dinnertime). The blood pressure response to the variation of sodium content in the meals was examined by means of noninvasive automated blood pressure monitoring (ABPM-630; readings every 15 or 30 min over 48 h) and chronobiologic analysis. A significant shift of blood pressure circadian rhythm was observed in Stage-LH. Additionally, the 24-h mean level of blood pressure significantly increased when the prevailing salt intake was at lunch, and significantly decreased when the prevailing intake was at dinner. These opposite responses corroborate the view that the blood pressure susceptibility of human beings to salt intake varies during the day, showing its maximal expression at midday. Such a time-dependent sensitivity may be exploited for better nutritional prevention and treatment of arterial hypertension by reapportioning the salt intake so that two-thirds is consumed at dinner.

Localization of IL-1 beta mRNA and cell adhesion molecules in the maxillary sinus mucosa of patients with chronic sinusitis

Interleukin-1 beta (IL-1 beta) is a predominant cytokine in retained paranasal sinus fluid of chronic sinusitis where infiltration by polymorphonuclear neutrophils (PMNs) of nasal and paranasal mucosa is characteristic. The authors investigated the localization of IL-1 beta messenger RNA (mRNA) in the maxillary sinus mucosa of patients with chronic sinusitis, using digoxigenin-labeled oligonucleotide probes. IL-1 beta mRNA was detected in some extravascular PMNs and small numbers of mononuclear leukocytes but was not detected in other tissue cells or intravascular leukocytes. The expression and distribution of the cell adhesion molecules, intercellular adhesion molecule-1 (ICAM-1) and endothelial-leukocyte adhesion molecule-1 (ELAM-1), were also studied in cultured human mucosal microvascular endothelial cells and in the maxillary sinus mucosa in chronic sinusitis by immunohistochemistry using monoclonal antibodies against these cell adhesion molecules. Only ICAM-1 was expressed on cultured human mucosal microvascular endothelial cells without IL-1 beta stimulation. With IL-1 beta activation of these cells, ELAM-1 was expressed strongly and the expression of ICAM-1 was enhanced. In the maxillary sinus mucosa, ICAM-1 was strongly and universally expressed on endothelial cells of all small vessels, whereas ELAM-1 was expressed only in the subepithelial region. These findings suggest that IL-1 beta, one of mediators in chronic sinusitis, is produced by PMNs, induces the expression of ICAM-1 and ELAM-1 on endothelial cells, and, thereby, stimulates PMN infiltration in chronic sinusitis.

Histochemistry and immunohistochemistry of extracellular matrix of rat fetal Ductus arteriosus during the indomethacin-induced constriction

Administration of anti-inflammatory non-steroidal drugs to pregnant animals causes constriction of the fetal ductus arteriosus (DA). To clarify the mechanism of the indomethacin-induced constriction of the rat fetal DA, extracellular matrix (ECM) components were observed by immunohistochemical techniques with antibodies 2B1, 6B6, 3B3, 9A2 and others to various kinds of proteoglycans (PGs). In the 10mg/kg group, the large PG revealed with antibody 2B1 was increased in the inner and outer media at constriction, and chondroitin 6-sulfate PG was strongly immunostained with antibody 3B3 as granular substances in the outer media, although no difference in stainability of chondroitin 4-sulfate PG revealed with the antibody 9A2 was observed between experimental and control groups. This suggests that the cells composing the fetal DA showed a tendency of proliferation and resultant production and aggregation of large PG with chondroitin 6-sulfate chains during constriction induced by indomethacin-treatment.

Development of a tissue culture assay system for Campylobacter jejuni cytotoxin and the influence of culture conditions on cytotoxin production

A tissue culture assay system to detect Campylobacter jejuni cytotoxin was developed, and the effect of culture conditions on cytotoxin production was examined. Broth-culture filtrates from clinical isolates were used. The expression of cytotoxicity was dependent on the presence of serum in the culture medium. Although the titre of cytotoxin was low, the greatest cytotoxicity was revealed when newborn calf (NCS), adult bovine or goat serum was added to minimum essential medium. Moderate or weak cytotoxicity was observed when fetal calf (FCS), swine or human serum was added, and no cytotoxicity was seen with the addition of horse, rabbit, cat or chicken serum. Furthermore, the cytotoxic titre in serum-free culture (SFC) for Chinese hamster ovary (CHO) cells was higher than that with serum supplementation. CHO cells showed the highest sensitivity in FCS, NCS and SFC assay systems, whereas HeLa, Vero, HEp-2 and Intestine 407 cells were sensitive only in the NCS assay. Brucella broth was excellent for cytotoxin production, but iron supplementation had no effect. Cytotoxic expression in the three assay systems differed between stationary and stirred cultures. Our results on cytotoxin production by reference strains of C. jejuni did not agree with the original reports. These findings suggest that several different cytotoxins may be produced by C. jejuni, and that the assay system may be important for the expression of cytotoxic activity.

The interplay of interleukin-10 (IL-10) and interleukin-2 (IL-2) in humoral immune responses: IL-10 synergizes with IL-2 to enhance responses of human B lymphocytes in a mechanism which is different from upregulation of CD25 expression

The role of the interplay of interleukin-2 (IL-2) and interleukin-10 (IL-10) in responses of human peripheral blood B cells stimulated by ligation of antigen receptors was examined in detail. Highly purified peripheral blood B cells from normal human individuals were cultured with Staphylococcus aureus Cowan I (SA) in the presence or absence of IL-10 and IL-2. Although IL-10 alone could modestly induce Ig production by SA-activated B cells, IL-10 markedly enhanced the Ig production in synergism with IL-2. This synergistic effect between IL-2 and IL-10 was completely abrogated by addition of either anti-CD25 mAb or anti-IL-10 mAb, indicating signals through high-affinity IL-2 receptors are involved in the synergism. In fact, IL-10 upregulated the expression of alpha-chain of IL-2 receptors (CD25) on B cells stimulated by SA alone or SA + IL-2 for 72 hr. However, such upregulation of CD25 expression did not result in significant enhancement of subsequent responses of the activated B cells to IL-2. Of note, during the initial activation phase of B cells, IL-2 was much more effective than IL-10 in enhancing the subsequent responses to either IL-2 or IL-10. By contrast, IL-10 was much more effective than IL-2 in supporting the maturation of B cells following the initial activation. Finally, the synergy between IL-2 and IL-10 was not observed in the initial activation phase, but in the subsequent maturation phase of activated B cells. These results indicate that IL-10 and IL-2 synergistically enhance Ig production of SA-activated B cells in a mechanism which is different from the upregulation of IL-2 receptors. Moreover, the data emphasize the importance of the interplay of IL-2 and IL-10 in determining the outcome of humoral immune responses.

Heparan sulfate proteoglycans are required for mesoderm formation in Xenopus embryos

Mesoderm forms in the vertebrate embryo as a result of inductive interactions involving secreted growth factors and cell surface molecules. Proteoglycans have recently been implicated in the control of cell adhesion, migration and growth factor responsiveness. We have found that removal of glycosaminoglycan chains of proteoglycans from Xenopus ectodermal explants by heparinase, but not by chondroitinase, results in inhibition of elongation and mesodermal differentiation in response to signaling factors: activin, FGF and Wnt. Heparinase treatment differentially affected expression of early general and region-specific mesodermal markers, suggesting that mesodermal cell fates become specified in the early embryo via at least two signaling pathways which differ in their requirements for heparan sulfate proteoglycans. Addition of soluble heparan sulfate restored activin-mediated induction of muscle-specific actin gene in heparinase-treated explants. Finally, heparinase inhibited autonomous morphogenetic movements and mesodermal, but not neural, differentiation in dorsal marginal zone explants, which normally give rise to mesoderm in the embryo. These results directly demonstrate that heparan sulfate proteoglycans participate in gastrulation and mesoderm formation in the early embryo.

Cyclic haemopoiesis at 7- or 8-day intervals

We report a patient with severe anaemia and cyclic oscillations of reticulocyte and leucocyte counts, as well as serum iron (Fe), unsaturated iron-binding capacity (UIBC), ferritin, C-reactive protein (CRP) levels and temperature, at regular intervals of 7 or 8 d. After treatment with prednisolone, anaemia was corrected and the cyclic oscillations of these parameters ceased; whereas treatment with indomethacin, recombinant granulocyte-colony stimulating factor (G-CSF) and erythropoietin (Epo) were unsuccessful.

Elevated adenosine deaminase activity in the serum of patients with diabetes mellitus

Adenosine deaminase (ADA) is suggested to be an important enzyme for modulating the bioactivity of insulin, but its clinical significance in diabetes mellitus (DM) is not yet characterized. We measured the serum levels of ADA isoenzymes (ADA1 and ADA2) in healthy donors (HD, n = 52), insulin-dependent diabetes mellitus (IDDM, n = 53) patients and non-insulin-dependent diabetes mellitus (NIDDM, n = 65) patients. The mean serum level of ADA1 in HD, IDDM or NIDDM patients was, respectively 6.5, 8.1 or 9.5 units/l (P < 0.001 vs. HD) and that of ADA2 in HD, IDDM or NIDDM patients was 7.0, 14.9 (P < 0.001 vs. HD) or 11.2 units/l (P < 0.001 vs. HD), respectively. Normalization of the blood glucose level by the hospitalization was associated with the decrease in ADA2 (but not ADA1) activity in 6 of 8 IDDM or 11 of 12 NIDDM poorly controlled patients. ADA2 (but not ADA1) activity in the poorly controlled NIDDM patients directly correlated with the hemoglobin A1c level (P < 0.002). Measurement of serum ADA2 activity may be important to better understand the clinical aspects of both IDDM and NIDDM. The pathogenic role of elevated ADA activity in the sera of DM patients was addressed.

Noise characteristics of a Nd:YVO(4) laser pumped by laser diode modulated at high frequency

We report, for the first time to our knowledge, on the noise characteristics of a Nd:YVO(4) laser pumped by a laser diode modulated at high frequency. We have investigated noise characteristics of a Nd:YVO(4) laser pumped by a laser diode that is oscillating in a stable multilongitudinal mode because of modulation by a high-frequency (several hundred megahertz) current. As a result, low-noise operations of -130 dB/Hz above frequencies of 1 MHz have been achieved. This noise level is comparable to the level obtained when pumping a Nd:YVO(4) laser with a laser diode that is oscillating in a single longitudinal mode. However, a noise peak corresponding to relaxation oscillations of the Nd:YVO(4) laser has appeared around a frequency of several hundred kilohertz.

Polyclonal uses of T-cell receptor (TCR)alpha and beta genes for cytotoxic T lymphocytes in human metastatic melanoma: possible involvement of TCR alpha in tumor-cell recognition

Identification of genetic structure and diversity of T-cell receptor (TCR)alpha and beta genes for cytotoxic T lymphocytes (CTLs) infiltrating human cancers is important for the better understanding of molecular mechanisms of host defense at tumor sites. cDNAs of TCR alpha and beta genes of 22 different melanoma-specific CTL clones established from the tumor-infiltrating lymphocytes of 2 patients were sequenced for analysis of their genetic structure and diversity. V alpha 7.2-J alpha 10-C alpha was found in 4 of 22 clones, 2 of which also used the same beta-chain. The other 20 clones showed different combinations of alpha and beta use. At deduced amino-acid levels, 7 of 9 clones from one patient used a threonine residue at the 26th position in the complementarity-determining region (CDR)1 of TCR alpha. Eight of 13 clones used a threonine at the 99th or a serine residue at the 100th position in CDR3 of TCR alpha CTL clones with the same or different TCR alpha showed the same or different patterns of cytotoxicity, respectively. These results suggest that CTLs usually do not demonstrate clonal expansion at tumor sites of metastatic melanoma's but rather that polyclonal T cells capable of binding to multiple melanoma determinants through CDR3 of TCR alpha accumulate in the tumor.

The distribution of [11C]cocaine in normal and cocaine-sensitization mice

[N-11C-methyl]-cocaine ([11C]cocaine), synthesized by N-methylation of norcocaine with [11C]CH3I, was used to assist in imaging the variety of local distribution by positron emission tomography (PET). The radiochemical yield and the radiochemical purity after purification of [11C]cocaine by high performance liquid chromatography (HPLC) at a sp. act. of 814 GBq/mmol were 47-58% and > 99%, respectively. The time required for synthesis including the purification was 25-30 min from the end of [11C]CH3I trapping. The physical distribution of [11C]cocaine in organ was also investigated in mice at various time after i.v. injection. The main accumulation of radioactivity occurred in the lung, kidney and brain within 1 min after the injection. In the brain, no differences in the organ were observed except the radioactivity level in each section increased for the first 5 min, since then radioactivity decreased dramatically. Furthermore, in the behavioral sensitization model of cocaine, the peak of [11C]cocaine uptake in each brain area was shown to be 5-15 min.

[Anesthesia for bronchoscopy: application of laryngeal mask airway and "minidose midazolam anesthesia"]

Bronchoscopy distresses most of the patients. Therefore, we combines a small dose of midazolam (ca. 2 mg) with laryngeal mask airway. This method of anesthesia has the following features: (1) mild discomfort, (2) day care, (3) putting bronchoscope in or out easily, (4) mild effect on respiration and circulation, and (5) easy respiratory care. But improper cases for this method include non-fasting patients, those at high risk for regurgitation, and those with low pulmonary compliance. This is a very usefull anesthetic method for bronchoscopy.

Retention index of thallium-201 single photon emission computerised tomography (SPECT) as an indicator of metastasis in adenocarcinoma of the lung

We examined the relationship between the retention of thallium-201 (201Tl) on a delayed scan and the metastatic potential of adenocarcinomas of the lung. We studied 43 patients with adenocarcinoma of the lung and divided them into two groups according to the presence or absence of lymph node metastasis. 201Tl single photon emission computerised tomography (SPECT) was conducted twice: 15 min (early scan) and 120 min (delayed scan) after intravenous injection of 3 mCi of 201Tl chloride. We calculated the retention index in order to evaluate the degree of 201Tl retention in the primary tumour. The retention indices were significantly higher in the group that was positive for lymph node metastasis than in the negative group. In adenocarcinomas with high metastatic potential, 201Tl SPECT demonstrated slow washout or increased retention on the delayed scan. The retention index of 201Tl SPECT is a useful indicator of metastatic potential, thereby facilitating the prediction of prognosis, and provides insight into the relationship between 201Tl uptake and malignancy. This is the first report demonstrating a significant relationship between the retention of 201Tl SPECT and lymph node metastasis.