[Aluminum in renal osteodystrophy]

To evaluate the relationship between aluminum and renal osteodystrophy, iliac bone biopsies and bone aluminum staining were studied in 51 patients with end-stage renal failure. In 27 of 51 cases were measured PTH, 1.25 (OH)2D3 levels and bone aluminum contents. We found that the incidence of renal osteodystrophy was 100%. The positive rate of bone aluminum staining was 12%. The rate was highest in low-turnover osteomalacia. Serum aluminum and bone aluminum contents were significantly higher than controls in three types of renal osteodystrophy on hemodialysis. Bone aluminum correlated with the duration of hemodialysis (r = 0.704), also with the serum calcium (r = 0.341). The duration of hemodialysis and bone aluminum contents were markedly longer and higher in positive group of bone aluminum staining than that of negative group (P < 0.001, respectively). Our data suggested that: (1) aluminum accumulation in bone was related to duration of hemodialysis, (2) aluminum may play important roles in the intervention of bone mineralization.

Differential effects of endothelin-1 on normal and postischemic reperfused myocardium

Using an isolated rat heart preparation and 31P magnetic resonance spectroscopy, we studied the effects of endothelin-1 (ET-1) and U-46619, a thromboxane-A2 analogue, on coronary flow (CF), left ventricular developed pressure (LVP), and high-energy phosphate metabolism under control conditions (normal myocardium) and during postischemic reperfusion (reperfused myocardium). The selected doses of ET-1 and U-46619 reduced CF in the normal myocardium to a similar extent (47.8 +/- 1.5% and 48.7 +/- 4.6%, respectively). In contrast to ET-1, U-46619 induced a depression of LVP (20.2 +/- 6.9% versus 6.8 +/- 4.7%; p < 0.05) which was accompanied by an intracellular acidosis, indicating that a low-flow ischemia occurred. In reperfused hearts, the ET-1-induced decrease in CF was more pronounced compared to U-46619 (79.5 +/- 1.6% versus 59.0 +/- 5.9%; p < 0.05) and to ET-1-induced decrease in CF in the normal myocardium (74.0 +/- 7.9% versus 32.4 +/- 6.3%; p < 0.05). This was accompanied by a large decrease in LVP and in levels of high-energy phosphate compounds. Therefore, the effects of ET-1 but not of U-46619 are enhanced in reperfused hearts. This may contribute to the delayed recovery of the postischemic reperfused myocardium.

Influence of reducing luxury calories in the treatment of experimental mammary carcinoma

The aim of this study was to investigate the influence of dietary calorie intake at three different fat levels on (a) the growth of established methylnitrosourea (MNU)-induced mammary carcinoma, (b) the reappearance of mammary carcinomas after surgical removal, and (c) the growth of manifest lesions in animals treated with the cytostatic agent hexadecylphosphocholine (HPC). A reduction of calories by 30% significantly inhibited tumour growth of manifest mammary carcinomas in rats, without having a negative influence on body weight gain. After chemotherapeutic treatment no significant dietary influence was observed besides the high antineoplastic efficacy of HPC, but when feeding calorically restricted diets to surgically treated animals the number of reappearing tumours was considerably smaller (P = 0.06) than after feeding the diets ad libitum. The fat content of the diets did not influence the growth of manifest mammary carcinomas. No significant dietary effects were exerted on oestradiol or testosterone levels in untreated tumour bearing animals. An elevation of oestradiol levels was observed when animals were subjected to HPC and fed a high calorie diet. An elevation of testosterone levels was assessed after surgical treatment of the rats, irrespective of fat content and calorie level. Our results suggest that a reduction of calories can inhibit growth of manifest mammary carcinomas and has impeding effects on tumour development after surgical removal. After effective chemotherapeutic treatment the additional influence of dietary changes was of less relevance. Furthermore, our data do not establish any association between growth inhibition of mammary tumours, caused by the mild caloric restriction, and altered oestradiol or testosterone production.

Effects of Hantaan virus on human endothelial cells and their significance in pathogenesis of hemorrhagic fever with renal syndrome

The effects of Hantaan virus (HTNV) on human endothelial cells (HECs) were investigated both in vivo and in vitro. The 76-118 strain or SR-11 strain of HTNV were inoculated into HECs monolayers respectively, and the virus antigens could be detected on the seventh day of the first passage after inoculation by immunofluorescent technique. The HTNV could also be isolated through cultures of Vero E-6 cells. HTNV particles and inclusion bodies together with various changes in the organelles were observed in the infected cells by transmission electronic microscopy (TEM), and the immunoenzyme positive virus particles were seen by immunoelectronic microscopy. Samples of skin biopsy were individually obtained from 14 cases of hemorrhagic fever with renal syndrome on the second to the fifth day after the onset of the illness. It was found that HTNV antigens were widely distributed in the cytoplasm of endothelial cells of the samples from 5 out of 14 cases by avidin-biotin-peroxidase complex staining, and morphologic changes of the endothelial cells similar to those observed in vitro, were also seen by TEM. The results indicated that HEC is one of the target cells susceptible to HTNV. The virus could invade and propagate in HECs, and could induce damage to the latter.

Effect of dietary calorie and fat restriction on mammary tumor growth and hepatic as well as tumor glutathione in rats

Effect of dietary calorie restriction and fat reduction on growth of established mammary carcinoma in rats and on glutathione levels in liver and tumor tissue was investigated. Reduced (GSH) and oxidized (GSSG) glutathione were determined enzymatically. Female Sprague-Dawley rats were injected with 25 mg/kg methylnitrosourea (MNU) on day 50 of life for tumor induction, and subsequently fed a diet containing 50 kcal/day with 45% (energy %) fat. When tumors reached approximately 1 cm3, the diet was changed for 10 +/- 2 weeks. Four dietary groups were formed: two high calorie groups (50 kcal/day) with 45% or 25% fat and two calorie restricted groups (35 kcal/day) with 45% or 25% fat, respectively. Tumor growth was significantly inhibited by the 30% calorie restriction, and the inhibition was most effective in the calorie restricted group with low fat level. However, reduction of fat, alone, had no significant inhibitory effect. GSSG levels in both liver and tumor showed no differences among the groups. Hepatic GSH levels tended to be lower in the calorie-restricted groups, and showed no difference between isocaloric groups with different fat levels. In contrast, GSH in tumor tissue tended to be lower in the low fat groups, independently of calorie levels.

Design and implementation of full-frame, bit-allocation image-compression hardware module. Work in progress

A hardware module was designed and built to implement the full-frame, bit-allocation image-compression algorithm in a clinical setting. The algorithm transforms an entire image without prepartitioning into small subimages. This adaptation eliminates block artifacts at subimage borders that can mimic relevant pathologic conditions. The quality of 1,024- and 2,048-pixel images compressed at a rate up to 10:1 with a custom-designed processor board (which contains four digital signal processors that transform and quantize separate rows and columns of an image independently with a two-pass cosine transform) and a 16-Mbyte frame buffer was found to be diagnostically acceptable in preliminary receiver operating characteristic studies. The module can compress a 1,024-pixel image in 4 seconds in a general-purpose computer system; images can be compressed in 1 second with the addition of a custom-designed data transporter. Copies of the compression module are being installed in the authors' department and in collaborating hospitals for laboratory and clinical evaluation.

Vertical frontal subtotal laryngectomy and immediate reconstruction of larynx with cervical skin flap

Vertical frontal subtotal laryngectomy, a procedure that can remove as much as 90% of the larynx, was used to produce a functionally acceptable neolarynx with adjacent cervical skin flaps. Thirty-four patients with laryngeal carcinoma underwent this operation. All patients were staged according to their physical findings before operation. Of these patients, 1 was lost to follow-up and 2 died from other causes 6 months and 4 years after operation respectively. The remainder are living and well without recurrence. The longest follow-up was 8 years and the shortest 14 months. Laryngeal functions were restored completely in 27 patients and partially in 7. We conclude that the procedure is best suited for the removal of anterior commissure tumor extending from both vocal cords to the anterior 1/3 or the entire length of the true cords and that if the tumor extends to the supraglottis or subglottis, this procedure is adequate as long as the posterior part of the larynx is not involved, leaving a sufficient safety margin.

[Experimental study on myocardial protection with verapamil and salvia miltiorrhiza Bunge cardioplegia]

Myocardial 45Ca sequestration was studied in dogs during 60 minutes of global ischemia and 30 minutes of reperfusion using cardiopulmonary bypass (CPB) and myocardial function was studied before and after CPB. Group A (n = 5), as a control, received cold hyperkalemic cardioplegic solution, Group B (n = 5) received the same solution plus verapamil (150 micrograms/kg/L) and Group C plus specific activity (TSA = DPM x 10(4)/g) and plasma specific activity (PSA = DPM x 10(4)/ml) were determined by biopsy before and after release of the cross-clamp The results showed that myocardial function in Group B and C were better than that in Group A (P less than 0.01). It is suggested that verapamil and Salvia miltiorrhiza Bunge effectively control myocardial calcium sequestration during early reperfusion and reduce myocardial reperfusion injury As to myocardial protection, cardioplegia with verapamil and Salvia miltiorrhiza Bunge were superior to hyperkalemic alone. Verapamil cardioplegia was still better than Salvia miltiorrhiza Bunge.

[Intracytoplasmic desmosome in squamous cancer cells of the lung in man]

Ultrastructure of intracytoplasmic (cytoplasmic) desmosomes in the squamous cancer cells of the human lung was studied by electron microscopy. In 17 cases of non-keratosic squamous cell carcinoma of the lung, intracytoplasmic (cytoplasmic) desmosomes were found in 4. In contrast to what previous investigators had proposed that the intracytoplasmic desmosomes are formed by cell fusion with the membrane being deep in the cell and cell digestion under the diffusion of hydrolytic enzymes, our result indicates that the intracytoplasmic desmosomes might be a structure formed by cell intima system itself during cell division. The structure suggests that the desmosomes originate from the cell intima system.

Purification and primary structures of duck fibrinopeptides A and B

Duck fibrinopeptides A and B were purified by Dowex 50 W X 2 ion exchange resin and DEAE-Sepharose CL-6B. The complete primary structures of duck fibrinopeptides A and B were determined by manual Edman Sequence determination. The primary structure of duck fibrinopeptide A is pyr. Asp. Gly. Lys. Ser. Ser. Phe. Gln. Lys. Glu. Gly. Gly. Gly. Val. Arg., and that of duck fibrinopeptide B is Pyr. Ala. Ser. Thr. Asp. Tyr. Asp. Asp. Glu. Asp. Glu. Ser. Thr. Val. Pro. Glu. Ala. Arg.

Transformation of ultrastructural type of fast-twitch muscle fibres after cross-innervation by tetrodotoxin-blocked slow muscle nerve

It is shown in rats that cross-innervation of the fast-twitch muscle extensor digitorum longus (EDL) by the nerve of the slow-twitch muscle soleus (SOL) can cause a complete transformation of the Z-band width from the fast to the slow muscle fibre type within two weeks and that it can still induce such a transformation, though usually less completely, even when impulse activity is excluded by chronical tetrodotoxin (TTX) block of the nerve. This provides a piece of clear-cut evidence for the presence of some activity-independent trophic factor in the neural determination of skeletal muscle fibre type.