Cellular models and tissue equivalent systems for evaluating the structures and significance of age-modified proteins

The accumulation of modified proteins in aging is well documented in many aging models. For example, the deamidated isoforms of triosephosphate isomerase accumulate in: (a) old erythrocytes, (b) fibroblasts from old donors, (c) fibroblasts aged in vitro, (d) premature-aging syndromes and (e) old cells in the eye lens. However, a fundamental remaining question is: 'Do such modified proteins interfere with cellular function?' It has been difficult to assess this question at the molecular level using whole-organism models and equally frustrating to evaluate the physiological significance of such changes using classical cellular models. Tissue equivalent systems (TES) provide an opportunity for examining the molecular basis and physiological consequences of modified proteins during aging. TES are composed of differentiating and proliferating heterogeneous cell types with symbiotic cell-cell and cell-matrix interactions. They closely resemble, both morphologically and functionally, the tissues from which they were derived. Aging studies utilizing TES can provide information on modifications of protein structures, isozyme patterns, enzymes of the cellular environmental protection system and metabolic parameters which may regulate protein synthesis and degradation.     

MRI and ultrasonography of atherosclerosis of the thoracic aorta and carotid arteries in elderly hypercholesterolemic patients]

In 53 elderly participants aged more than 60 the thoracic aorta and bilateral carotid arteries were observed with noninvasive techniques, MRI and ultra-sonography, in order to elucidate the relationship between hypercholesterolemia and atherosclerosis in the elderly. Hypercholesterolemic subjects were classified as group H (serum total cholesterol (TC) greater than 220 mg/dl), group H-I (220 mg/dl less than TC less than 250 mg/dl) and group H-II (TC greater than or equal to 250 mg/dl). Atherosclerotic changes of the thoracic aorta were observed in 46% of group H, 27% of group H-I, 60% of group H-II and 37% of normolipidemic subjects (group NL). Carotid atherosclerotic changes were observed in 19% of group H, 9% of group H-I, 27% of group H-II and 18% of group NL. In group H-I, the percentages of atherosclerotic changes in both thoracic aorta and carotid arteries were lower than those in group NL. However, atherosclerotic changes of thoracic aorta and carotid arteries were detected in 43% and 29% of the subjects showing higher apo B/Apo Al ratio than 1.0 among group H-I + NL (TC less than 250 mg/dl). These changes occurred in 32% and 13% of the subjects showing lower apo B/Apo Al ratio than 1.0 among the same groups. Namely, atherosclerotic changes of the thoracic aorta and carotid arteries were observed more frequently in the subjects showing a higher apo B/Apo Al ratio than 1.0 even if their serum cholesterol values were not higher than 250 mg/dl. We should use not only the serum cholesterol value but also the apo B/Apo Al ratio as an indicator to evaluate the roles of lipids in the development of atherosclerosis.     

Recombinant forms of Gerbich blood group antigens: expression and purification.

Recombinant forms of normal glycophorin C (GPC), carrying the high frequency Gerbich blood group antigens, and its natural deletion mutants of Yus and Ge type (all combined with oligohistidyl tag) were expressed in CHO and COS 7 cells. The stable expression of all recombinant forms of GPC in CHO cells was obtained, but the level of expression was low and detectable only by flow cytometry. The high level of transient expression of GPC recombinant forms in COS 7 cells allowed their purification on Ni-NTA-agarose. The purified recombinant GPC and mutants of Yus and Ge type behaved in SDS-PAGE similarly to normal GPC forms from RBC membranes. The recombinant GPC.Yus and GPC.Ge mutants appeared as diffuse bands, suggesting the similar heterogeneity of glycosylation that was observed in natural GPC.Yus and GPC.Ge glycoproteins. The flow cytometry analysis of the transfected CHO and COS 7 cells showed that binding of anti-GPC monoclonal antibodies to GPC variants was accordant with the known fine specificity of these antibodies. The obtained recombinant forms of GPC carrying common Gerbich antigens may be useful in serology, and also as model molecules for structure-function studies.     

Covered metal stent for tumor obstruction of efferent loop recurrence after gastrectomy

Reports the case of a 60-year-old woman who underwent R2 total gastrectomy, and subsequent palliation of painful symptom recurrence via a membrane-covered metal stent. Received: 13 June 1996/Accepted: 31 July 1996     

Brucellosis of the spine with a synchronous Staphylococcus aureus pyogenic elbow infection

Staphylococcus aureus osteomyelitis and pyogenic arthritis has a different pattern in the elderly than in the young. The axial skeleton is the most frequent site of infection and treatment is usually by intravenous antibiotics. We report a case ofStaph. aureus septic arthritis of the elbow with concomitant osteomyelitis of the spine that was thought to be due toStaph. aureus, but culture of debrided material from the lesion grewBrucella in culture. We suggest that in the elderly it is advisable to obtain a tissue culture diagnosis and not to instigate therapy based on positive blood cultures or a concomitant infection.     

A study on plasma norepinephrine and epinephrine levels in TCM liver syndromes.

The levels of plasma norepinephrine (NE) and epinephrine (E) were determined by HPLC in 220 patients with various TCM liver syndromes, and in 96 healthy subjects as controls. The plasma NE and E contents were higher in patients with liver excess syndromes, including Ganqi Yujie (GQYJ [symbol: see text]) syndrome, Ganyang Shangkang (GYSK [symbol: see text]) syndrome, Ganhuo Shangyan (GHSY [symbol: see text]) syndrome, and Ganyang Huafeng (GYHF [symbol: see text]) syndrome; while they were lower in patients with liver deficiency syndromes, including Ganqixu (GQX [symbol: see text]) syndrome, Ganxuexu (GXX [symbol: see text]) syndrome, and Ganyinxu (GYX [symbol: see text]) syndrome. Futhermore, when Ganshen Yinxu (GSYX [symbol: see text]) syndrome was turned into GYSK and then into GYHF, the plasma NE and E contents increased in order of precedence; while when GQYJ was turned into Ganyu Pixu (GYPX [symbol: see text]) syndrome, both NE and E contents decreased. The results suggest that the plasma NE and E contents are reliable objective parameters for the study of pathophysiological basis of the liver excess and liver deficiency syndromes, and the liver-kidney and liver-spleen interrelated syndromes.     

Effects of Nitrite Exposure on Acid–Base Balance, Respiratory Protein, and Ion Concentrations of Giant Freshwater Prawn Macrobrachium rosenbergii at Low pH

Macrobrachium rosenbergii that had been exposed individually for 24 h to 0 (control), 2, 5, 10 mg/L nitrite-N (nitrite as nitrogen) at 4.3 and 7.7 pH levels were examined for hemolymph nitrite-N, oxyhemocyanin, protein, acid–base balance, ion concentrations, and ammonia-N (ammonia as nitrogen) excretion. Hemolymph oxyhemocyanin, protein, pH, HCO₃ ⁻ , TCO₂, osmolality, and ion concentrations were inversely related to ambient nitrite-N concentration and were lower at pH 4.3. However, hemolymph nitrite-N, PO₂ and PCO₂ levels, and ammonia-N excretion were directly related to ambient nitrite-N, and were higher at pH 4.3. Ambient nitrite-N and pH level interacted to cause changes in hemolymph nitrite-N, oxyhemocyanin, protein, PO₂, and pH levels. It is concluded that for M. rosenbergii following nitrite exposure, the incorporated nitrite causes a decrease of pH and an increase of PO₂ in the hemolymph where it reduces oxyhemocyanin level; disturbs nitrogen excretion, ion regulation, and respiratory gas exchange; and may lead to a decrease of oxygen-carrying capacity, which are affected more at low pH. Received: 31 August 1996/Accepted: 9 July 1997     

Results of speech perception and speech production training for three prelingually deaf patients using a multiple-electrode cochlear implant.

Five studies were conducted to measure changes in the perception and production of selected speech targets, with training, in three prelingually deaf patients. The two adults and one adolescent were implanted with the Cochlear (Nucleus) multiple-electrode prosthesis. The studies were perception and production of nasal consonants; perception of syllable-final consonants; perception and production of alveolar consonants; auditory-visual perception of alveolar consonants; and perception and production of vowels. Perceptual data were collected in the audition (implant)-alone condition, except for the auditory-visual perception of alveolar consonants where the audition-alone, vision-alone, and auditory-visual conditions were used. Speech perception data in the audition-alone condition were also collected from four postlingually deaf adult implant patients, without training, to indicate differences between the two classes of patients. The three prelingually deaf patients generally showed some improvements in speech production. In perception, improvements were recorded only for individual patients in some studies. The performance of the adolescent was better than that of the two adults in all cases. The perceptual performance of the postlingually deaf patients was superior to that of the prelingually deaf patients in all cases.     

Specific Changes of Urinary Excretion of Cross-Linked N-Telopeptides of Type I Collagen in Pre- and Postmenopausal Women: Correlation with Other Markers of Bone Turnover

Urinary excretion of cross-linked N-telopeptide of type I collagen (NTx) has been reported to be a specific marker of bone resorption [18]. We assessed a new immunoassay for NTx as an indicator of changes in bone resorption caused by spontaneous menopause and compared cross-sectionally the levels of urinary NTx, hydroxylysylpyridinoline (HP), lysylpyridinoline (LP), hydroxyproline (OH-Pr), other serum biochemical indices, and lumbar spine and proximal femur bone mineral density (BMD). Eighty-one Japanese women aged 22–77 participated in this study; 36 were premenopausal and 45 were postmenopausal. Urinary HP, LP, and NTx stayed at low levels in the premenopausal period and rose 21%, 30%, and 67% in the postmenopausal period, respectively. The rise in LP and NTx was statistically significant (P < 0.01), suggesting that NTx is mostly released from bone matrix when bone resorption is accelerated. When premenopausal women were divided into two age groups and postmenopausal women were divided into two groups according to years since menopause (YSM) there were significant differences in LP and NTx between women <4 YSM and women aged <40 and those women aged 41+ (P < 0.01 and P < 0.05, respectively). A significant 110% increase in urinary NTx and a 48% increase in urinary LP were observed in postmenopausal women compared with age-matched premenopausal women aged 45–55. All biochemical markers other than serum PTH correlated significantly with each other (r = 0.243–0.858, P < 0.05–0.0001). Urinary NTx inversely correlated with lumbar spine BMD. When postmenopausal women were divided into three groups, the correlation between bone resorption and formation markers in women 0-1 YSM was greater than in women 2–10 YSM and in women 11 + YSM, indicating that resorption and formation are coupled at the early postmenopausal period. We conclude that urinary NTx is responsive to changes in bone metabolism caused by estrogen deficiency and may be a more sensitive and specific marker than HP, LP, or OH-Pr in the early postmenopausal years. Received: 15 February 1995 / Accepted: 18 October 1996