Use of canine red blood cell with high concentrations of potassium, reduced glutathione, and free amino acid as host cells for in vitro cultivation of Babesia gibsoni

OBJECTIVE

To determine the usefulness of canine RBC with high concentrations of potassium, reduced glutathione (GSH), and amino acid(i.e., HK cells) for in vitro cultivation of Babesia gibsoni.

ANIMALS

RBC were obtained from 3 dogs that had inherited HK cells and from 3 genetically unaffected dogs that, therefore, had RBC with lower potassium (LK) concentrations (i.e., LK cells).

PROCEDURES

First, B. gibsoni were cultivated using HK or LK cells in alpha-modification of Eagle medium, consisting of Earle salts with glutamine and without ribosides, deoxyribosides, and sodium bicarbonate under a humidified atmosphere containing 5% CO2 at 37 C. Second, parasites were cultivated with LK- or HK-cell lysates. Finally, HK cells were separated into 3 fractions (bottom, middle, top layers) by density gradient centrifugation, and B. gibsoni were cultivated with each of the HK-cell fractions. In addition, the concentrations of free amino acids and reduced glutathione (GSH) in each HK-cell fraction were measured.

RESULTS

B. gibsoni preferentially multiplied in HK-cell cultures rather than in LK-cell cultures. Furthermore, the addition of HK-cell lysate to the culture medium resulted in enhanced multiplication of the parasites. Higher multiplication of the parasites was observed in HK cells from the top layer, compared with HK cells from the middle and bottom layers. The HK cells from the top layer had higher concentrations of glutamate, aspartate, and GSH, compared with HK cells from the middle and bottom layer.

CONCLUSIONS

Canine HK cells are useful host cells for in vitro cultivation of B. gibsoni, and the high concentrations of glutamate, aspartate, and GSH may result in enhancement of multiplication of the parasites in HK cells.

[Combination effect of teicoplanin and beta-lactams on MRSA]

In vitro combination effect of teicoplanin and beta-lactams was investigated against 109 MRSA strains isolated from a variety of clinical specimens at the Social Health Insurance Medical Center during the period from January 1994 through February 2000. TEIC + panipenem (PAPM) was revealed by microbroth dilution method-based checkerboard method, to exhibit synergistic effect of min. FIC index < or = 0.5 against all the 109 strains. The combination of TEIC and flomoxef (FMOX) was shown to have synergistic effect on 108 strains (99.1%). The combination of TEIC and cefepime (CFPM) was shown to have synergistic effect on 96 strains (88.1%). The combination of TEIC and cefmetazole (CMZ) was shown to have synergistic effect on all the 109 strains (100%). The mean value of min. FIC indices obtained from each of the combinations was 0.1259 as to TEIC + PAPM, 0.2019 as to TEIC + FMOX, 0.3257 as to TEIC + CFPM and 0.1995 as to TEIC + CMZ, in other words, the combination of TEIC + PAPM showed the lowest value of all the combinations. While MIC80 was 2.0 micrograms/ml when TEIC was used alone, it was < or = 0.06 microgram/ml when used together with PAPM, and 0.13 microgram/ml when used together with FMOX, respectively. While MIC80 was 3.2 micrograms/ml when PAPM was used alone, it was 0.5 microgram/ml when used together with TEIC. Meanwhile, the value for FMOX was changed from > or = 128 micrograms/ml to 4.0 micrograms/ml. When TEIC was used in combination with CFPM, MIC80 was found to be 0.5 microgram/ml. Similar to the case of the concurrent use with FMOX, the value obtained by combination with CMZ was 0.13 microgram/ml. While MIC80 was 128 micrograms/ml when CFPM was used alone, it was 8.0 micrograms/ml when used together with TEIC, whereas the value for CMZ was decreased from 64 micrograms/ml to 2.0 micrograms/ml. In conclusion, TEIC's antibacterial activity was shown to be accentuated by any of the combinations.

Postmortem pathological examination of a case one month after carotid artery stenting

SUMMARY

There have been few pathological reports on human carotid stenting. A 73-year-old diabetic male with 80% stenosis in the left carotid bifurcation. Despite no neurological events, he died of pneumonia one month after. Findings pathological examination revealed: successful dilatation without deformity of the stent, eccentric compression and partial disruption of the plaque by struts, thrombi around disrupted plaque, and neointimal growth. Findings were generally compatible with those reported on coronary stenting. Case accumulation is required to clarify an exact pathological process and establish a procedure to reduce complications.

Abnormal glucose tolerance, not small vessel diameter, is a determinant of long-term prognosis in patients treated with balloon coronary angioplasty

AIMS

We sought to find out what factors are important for long-term prognosis, the small vessel itself or abnormal glucose tolerance, in patients treated with coronary angioplasty.

BACKGROUND

Patients with coronary artery disease with diabetes mellitus often show diffuse and small coronary artery narrowing. Impaired glucose tolerance has also been reported to be a risk factor for cardiovascular disease.

METHODS

Among 584 patients who underwent first elective balloon coronary angioplasty, diabetes mellitus and impaired glucose tolerance were present in 197 patients. Large and small vessels were defined by reference vessel diameter before coronary angioplasty as either larger or smaller than 2.5 mm. Patients were categorized into the following four groups: 175 patients with normal glucose tolerance and reference diameter <2.5 mm (group SN), 212 patients with normal glucose tolerance and reference diameter greater than or = 2.5 mm (group LN), 101 patients with abnormal glucose tolerance and reference diameter <2.5 mm (group SD), and 96 patients with abnormal glucose tolerance and reference diameter greater than or = 2.5 mm (Group LD). The cardiac events were compared for a period of 8 years after coronary angioplasty among the four groups.

RESULTS

There was no difference in the percentage diameter stenosis immediately after coronary angioplasty among the four groups. However, group SD showed unfavourable prognosis despite similar minimal lumen diameter after coronary angioplasty compared with group SN. Event-free survival curve of group LD showed a sudden drop approximately 5 years after the coronary angioplasty. In multivariate analysis, the cardiac events were associated with the presence or absence of abnormal glucose tolerance. Furthermore, patients with bad glycaemic control (HbA1c>6.0%) at index coronary angioplasty showed worse event free survival than those with good glycaemic control.

CONCLUSIONS

An important determinant for long-term prognosis after coronary angioplasty is a presence of abnormal glucose tolerance per se and not small vessel diameter.

[The effect of exogenous nitric oxide on endothelial dysfunction in two-kidney, one-clip renovascular hypertensive rats]

Previous studies have shown that hypertension causes endothelial dysfunction. To study the influence of exogenous nitric oxide(NO) on endothelial dysfunction produced by hypertension, we administered a non-depressor dose of nipradilol to two-kidney, one-clip renovascular hypertensive rats(2K1C). Sprague-Dawley rats underwent either sham surgery(G-1) or clipping of the left renal artery. From day seven, 2K1C were randomized into 3 groups, placebo treatment(G-2), nipradilol treatment(G-3,) and propranolol treatment(G-4). Urinary NO2- + NO3-(NOx) excretion (UNOx V) was measured 4 weeks after clipping, and then, acetylcholine(Ach), A23187, or sodium nitroprusside(SNP)-induced relaxation were measured in the aorta. Blood pressure was increased in G-2, G-3, and G-4 compared to G-1. UNOx V was lower in G-2, G-3, and G-4 compared to G-1, but UNOx V was higher in G-3 compared to G-2 and G-4. Although Ach or A23187-induced relaxation was significantly decreased in isolated artery from G-2, G-3, and G-4 compared with those from G-1. Ach- or A23187-induced relaxation was improved in G-3. SNP-induced relaxation did not differ among the 4 groups. These results suggest that exogenous NO from nipradilol reduces the endothelial dysfunction caused by hypertension without changing the blood pressure.

[Dietary intake of trace elements in the general population, estimated from a regional nutritional survey, and comparison with recommended dietary allowances and tolerable upper intake levels]

OBJECTIVES

Dietary intake by the general population of trace elements related to human health is not well known. Therefore, values for zinc, copper, manganese, chromium, selenium, molybdenum, cobalt and aluminum were estimated from food intake data from the 1993 Tottori Prefecture Nutritional Survey. For each element, consumption by the individual person was compared to the recommended dietary allowance (RDA) and the tolerable upper intake level (UL).

METHODS

Daily intake of trace elements by individuals was calculated from food intake data of 1993 Tottori Prefecture Nutrition Survey by computer program written by visual C++ using the trace element food table published by Suzuki (1993) and compared with RDA and UL values.

RESULTS

1. The percentage of people whose intake of zinc was lower than the RDA was 72.0%. Those for copper and manganese were 69.8% and 39.2%, respectively. Persons aged over 60 years consumed less of those trace elements. 2. Few people had a chromium intake lower than the RDA. The same was the case for molybdenum and selenium. However, 9.2% of people had on intake of chromium in excess of the UL, and for manganese, molybdenum and selenium the figures were 0.7%, 81.6% and 9.6%, respectively. 3. The major sources of the trace elements were cereals, fish, meats, vegetables and beans.

CONCLUSIONS

It is necessary to investigate the reason for the low intake of zinc, copper and manganese. It is also to be recommended that food tables for trace elements be produced to feel compliance with the RDA and UL for trace elements.

The cause of the predilection of Babesia gibsoni for reticulocytes

This study was conducted to determine why Babesia gibsoni replicates well in reticulocytes. First, B. gibsoni was cultivated in resealed erythrocyte ghosts loaded with either erythrocyte or reticulocyte lysate, and in reticulocyte ghosts loaded with either erythrocyte or reticulocyte lysate. The parasites multiplied well in the erythrocyte or reticulocyte ghosts loaded with reticulocyte lysate compared to the other resealed cells loaded with erythrocyte lysate. Second, the parasites were cultivated in erythrocytes in culture medium supplemented with either erythrocyte or reticulocyte lysate. The parasites multiplied better in reticulocyte lysate-containing cultures than in erythrocyte lysate-containing cultures. Finally, the parasites were cultivated in erythrocytes in culture medium supplemented with glutamate, aspartate, asparagine, glycine, isoleucine, proline, taurine or GSH, which were present in higher concentrations in reticulocytes than in erythrocytes. Supplementation of the culture medium with glutamate and GSH resulted in enhancement of the multiplication of the parasites, while the other amino acids did not enhance the multiplication. These results indicated that the high levels of the multiplication of B. gibsoni in reticulocytes are partly due to the high concentrations of glutamate and GSH in reticulocytes.

Echocardiographic and pathological evaluation of atherosclerosis in the ascending aorta during coronary artery bypass grafting

We performed intraoperative echocardiography with an epiaortic probe to assess the correlation between echocardiographic appearance and pathological findings of the aorta and to examine the effect of cross-clamping on the aortic wall in 276 patients who underwent coronary artery bypass grafting. The ascending aorta was divided into three segments as follows: lower (L), upper (U), and innominate. The anterior (ant) and posterior (post) intimal thicknesses of each of the three segments were measured. The echogenicity at each of the six locations was examined and was classified as isoechoic or nonisoechoic (hyperechoic, hypoechoic, or mixed type). Tissue punched from the ant L wall of the ascending aorta for vein anastomosis was examined for the presence of atheroma. At the ant L, the prevalence of atheroma was significantly higher in nonisoechoic walls than in isoechoic walls (P = 0.049). We divided patients into two groups according to echogenicity at the U segments. Group A (n = 213) consisted of patients whose echogenicities at both ant U and post U were isoechoic. Group B (n = 63) consisted of patients with nonisoechoic echogenicity at ant U and/or post U. The intimal thicknesses at all six locations in Group B patients were greater than those of Group A (P < 0.01). Deformities at the clamp site after cardiopulmonary bypass were observed significantly more often in Group B than in Group A (P < 0.01). Our data suggest that a nonisoechoic aortic wall indicates more advanced atheroma and a higher risk of deformities at the clamp site. Examination of the echogenicity of the ascending aorta may be one method to reduce perioperative neurological complications.

IMPLICATIONS

We performed epiaortic echocardiography during coronary artery bypass grafting and found that the presence of atheroma and deformities at the cross-clamping site were significantly more prevalent in nonisoechoic walls than isoechoic walls.

[Clinical evaluation of cases with massive ascites accumulation after discontinuation of CAPD: an attempt to establish the concept of the pre-sclerosing encapsulating peritonitis(pre-SEP) state]

Sclerosing encapsulating peritonitis(SEP) is a most serious complication of continuous ambulatory peritoneal dialysis(CAPD). Although the criteria of diagnosis and guidelines for therapy of SEP have been proposed by the Japanese SEP Study Group already, SEP is refractory to treatment when the disease process is complete. It is important to detect the latent phase of SEP(pre-SEP state) in order to treat patients at an early stage. We evaluated the characteristics of ascites in four patients with massive ascites accumulation after discontinuation of CAPD. Age and the duration of CAPD of the subjects were 53.3 +/- 9.7 years and 126.5 +/- 6.8 months, respectively. However, the patients were withdrawn from CAPD because of peritonitis or ultrafiltration failure. We also followed cytokines and parameters of collagen metabolism of ascites in two patients during adrenocorticosteroid therapy and conducted a histopathological evaluation of the peritoneum of an autopsy case who had died of pneumonia. Ascites seems to be exudative because of the high concentration of protein, cytokines and parameters of collagen metabolism such as interleukin-1 beta, interleukin-6, transforming growth factor-beta 1, procollagen 3 peptide, and type IV collagen 7S, the levels of which were 21.3 +/- 9.3 pg/ml, 8,153 +/- 7,327 pg/ml, 6.7 +/- 3.6 ng/ml, 89.3 +/- 67.8 U/ml, and 59.0 +/- 36.2 ng/ml, respectively. The histopathological findings of the peritoneum from the autopsy case showed dense fibrous tissue permeated with inflammatory infiltration and widespread infiltration of fibrin. These findings suggested that the peritoneum was inflamed when massive ascites accumulated. The amount of ascites and concentration of cytokines and parameters of collagen metabolism of ascites diminished during adrenocorticosteroid therapy. We concluded that massive and refractory accumulation of ascites appearing after the discontinuation of CAPD should be regarded as a sign of the pre-SEP state, and prophylactic treatment should be started at this stage of disease.

Inhibition of chondrogenesis by parathyroid hormone in vivo during repair of full-thickness defects of articular cartilage

We studied the effects of parathyroid hormone (PTH) on differentiation of chondroprogenitor cells during the repair of full-thickness articular cartilage defects. Three-millimeter cylindrical full-thickness articular cartilage defects, which are small enough to be resurfaced spontaneously by hyaline cartilage, were created in the femoral trochlea of the rabbit knee. Recombinant human PTH(1-84) (hPTH[1-84]) (25 ng/h) then was administered into the joint cavity with an osmotic pump, or in control animals, saline alone was administered. The animals were killed at 1, 2, 4, and 8 weeks. At 1 week, the defects were filled with undifferentiated cells, regardless of the PTH treatments. By 8 weeks, well-developed cartilage covered the defects with reconstitution of subchondral bone up to the original bone-articular cartilage junction. In contrast, no evidence of chondrogenic differentiation was seen at any time during the experimental period in the defects treated with PTH. The reparative tissues also were examined immunohistochemically using anti-proliferating cell nuclear antigen (PCNA) and anti-PTH/PTH-related peptide (PTHrP) receptor antibodies. Interestingly, the chondroprogenitor cells that filled the defects expressed PTH/PTHrP receptor, suggesting that these cells are capable of responding to PTH/PTHrP signaling before overt chondrogenesis. Application of PTH did not interfere with proliferation but inhibited chondrogenic differentiation of the cells resulting in the formation of fibrous tissue that lost the expression of PTH/PTHrP receptor within 4 weeks.

Hippocampal cholinergic neurostimulating peptides (HCNP)

Neuronal development and differentiation require a variety of cell interactions. Diffusible molecules from target neurons play an important part in mediating such interactions. Our early studies used explant culture technique to examine the factors that enhance the differentiation of septo-hippocampal cholinergic neurons, and they revealed that several components resident in the hippocampus are involved in the differentiation of presynaptic cholinergic neurons in the medial septal nucleus. One of these components, originally purified from young rat hippocampus, is a novel undecapeptide (hippocampal cholinergic neurostimulating peptide; HCNP); this enhances the production of ChAT, but not of AchE. Later experiments revealed that: (1) a specific receptor appears to mediate this effect; (2) NGF and HCNP act cooperatively to regulate cholinergic phenotype development in the medial septal nucleus in culture; and (3) these two molecules differ both in their mechanism of release from the hippocampus and their mechanism of action on cholinergic neurons. The amino acid sequence deduced from base sequence analysis of cloned HCNP-precursor protein cDNA shows that HCNP is located at the N-terminal domain of its precursor protein. The 21 kDa HCNP precursor protein shows homology with other proteins, and it functions not only as an HCNP precursor, but also as a binding protein for ATP, opioids and phosphatidylethanolamine. The distribution and localization of HCNP-related components and the expression of their mRNAs support the notion that the precursor protein is multifunctional. In keeping with its multiple functions, the multiple enhancers and promoters found in the genomic DNA for HCNP precursor protein may be involved in the regulation of its gene in a variety of cells and at different stages of development. Furthermore, several lines of evidence obtained from studies of humans and animal models suggest that certain types of memory and learning disorders are associated with abnormal accumulation and expression of HCNP analogue peptide and/or its precursor protein mRNA in the hippocampus.

Three screening tests for patients with psychological problems who undergo plastic and reconstructive surgery

To investigate their quality of life, screening tests of emotion, coping with stress, and personality were developed for use with patients in plastic and reconstructive surgery who had psychological problems. The validity and reliability of each test were examined in a sample of 329 patients who were admitted to the Department of Plastic and Reconstructive Surgery. The reliability of each test was supported by factor analysis, adequate internal consistency, and test-retest correlations. Also, validity was acceptable. Although further examination is required, these screening tests seem suitable for use in research among this type of patient in Japan.

Gene 61.3 of bacteriophage T4 is the spackle gene

The bacteriophage T4 e gene encodes lysozyme (e-lysozyme), which releases progeny phage after normal infection of Escherichia coli cells. A mutation in the spackle gene suppresses the defect in e-lysozyme (Emrich, 1968). The spackle gene was mapped between genes 41 and 61, but its precise location has not previously been determined. In the current study, we constructed an amber mutant of gene 61.3, amST14, by site-directed mutagenesis. The gene 61.3 mutant shares phenotypes with spackle mutants: The amST14 mutant forms large plaques with sharp edges and exhibits truncated lysis inhibition, and furthermore, the mutation can suppress the defect in e-lysozyme activity. In addition, cloned gene 61.3 can rescue (by homologous recombination) as well as complement the S12 mutation in the spackle gene. These results strongly suggest that gene 61.3 is the spackle gene. Indeed, the S12 mutant has one base deletion of five in a consecutive A tract in the gene 61.3 coding region, substituting an unrelated 6-amino acid sequence for the 9 C-terminal amino acids in the gene 61.3 protein. The gene 61.3 protein is predicted to localize in the periplasmic space after cleavage of a signal sequence.

[The role of nitric oxide in deoxycorticosterone acetate-salt hypertensive rats]

The relationship between nitric oxide (NO) and blood pressure (BP) in deoxycorticosterone acetate-salt hypertensive rats (DOC) was investigated. Although urinary NO2- + NO3- (NOx) excretion (UNOxV) increased 2 weeks after surgery (2W-DOC), UNOxV decreased 4 weeks after surgery (4W-DOC) compared with that of the control. BP and UNOxV did not change in DOC after treatment with L-arginine (Arg-DOC). Aorta from 4W-DOC and Arg-DOC had significantly decreased relaxation responses to acetylcholine. Deendothelialized aorta from 4W-DOC and Arg-DOC had significantly decreased relaxation responses to lipopolysaccharide. These data suggest that: 1) transient increase of NO synthesis is accompanied by elevation of BP, but long-term elevation of BP decreases NO synthesis in endothelium and smooth muscle cells; 2) L-arginine supplement has no effect on the development of hypertension nor on NO production by endothelium and smooth muscle cells in DOC.

New remote-controlled growing-rod spinal instrumentation possibly applicable for scoliosis in young children

Progressive scoliosis in young children has been treated with "spinal instrumentation without fusion" to avoid interference with spinal growth. Patients have to undergo a series of operations to have instruments exchanged for maintaining the correction. We have developed a newly designed remote-controlled growing-rod spinal instrumentation system proposed for the treatment of progressive scoliosis in young children. It can be used to stretch and correct the spinal deformities repeatedly and non-surgically, by means of a remote controller, after the first instrumentation operation. The purpose of this study is to describe the possible clinical application of this system for the treatment of progressive scoliosis in young children. To this end, we used the system in five beagle dogs with induced scoliotic deformities. The maximum distraction force of the instrument was 194 N. Correction of 1 cm was performed non-surgically in awake animals 3 weeks after the instrumentation operation, and then correction of 1 cm was carried out again 6, 9, and 12 weeks after the operation. The average initial Cobb's angle of the induced scoliotic deformities was 25 degrees; this was corrected to 20 degrees, 15 degrees, 8 degrees, and 3 degrees, after the distractions at 3, 6, 9, and 12 weeks, respectively, postoperatively. All corrections were performed non-surgically without apparent complications. By repetitive distractions with the use of our new system, we may be able to reduce the number of operations required in young scoliotic children.

High levels of hippocampal cholinergic neurostimulating peptide (HCNP) in the CSF of some patients with Alzheimer's disease

Hippocampal cholinergic neurostimulating peptide (HCNP), originally purified from the hippocampus of young rats, enhances the cholinergic development of rat medial septal nuclei in vitro. This report concerns the determination of the HCNP content of the cerebrospinal fluid (CSF) of 173 clinically, and of 22 clinico-pathologically defined patients. A radioimmunoassay was used throughout. The HCNP level was relatively uniform among the clinically defined patients; for almost all non-Alzheimer's patients, the level fell within the range delimited by +/- 2 SD of the mean for all patients taken together, and none of them had a level above this range. By contrast, the early-onset Alzheimer's disease patients could be divided on the basis of their HCNP level into two groups, one with high levels (markedly above the mean +/- 2SD range), and the other with levels similar to those of the other patients. The analysis of the CSF samples obtained postmortem revealed that Group I Alzheimer-type dementia (ATD) patients with clinico-pathologically established diagnoses had a strikingly higher level of HCNP than patients with either Group II ATD or cerebral vascular disease. These results suggest that HCNP is involved in certain pathophysiological alterations associated with dementia, and that its determination may be useful in patient evaluation. Copyright 1998 Lippincott Williams & Wilkins