Gel filtration of egg phosphatidylcholine vesicles

The abilities of Sepharose 2B (Pharmacia), Controlled Pore Glass (Electro-Nucleonics) and Bio-Gel A150m (Bio-Rad) to purify small unilamellar vesicles prepared by sonication and the ethanol-injection methods were compared. The Bio-Gel causes complete aggregation of the sonicated vesicles and partial aggregation of the ethanol-injection vesicles. Both Sepharose and Controlled Pore Glass are acceptable for purifying vesicles from multilamellar liposomes; however, neither will separate the vesicles from sonication by-products which might be formed.

Photocontrol of the germination of onoclea spores: v. Analysis of germination processes by means of temperature

The physiological nature of photoinduced germination of Onoclea sensibilis L. spores was investigated by temporarily applying a range of temperatures, particularly 40 C, before and after short light treatment. Controls were germinated at 25 C.The preinduction phase, during which photosensitivity is maximally developed in the dark, is sensitive to temperature. Treatment at 40 C for 8 or more hours reduces the developed photosensitivity to a minimal level, but the inhibition by 40 C treatment is reversed slowly after subsequent incubation at 25 C in the dark. The postinduction phase, in which dark processes lead to stain uptake and eventually to visible protrusion, is also sensitive to temperature. Inhibition by 40 C occurs shortly after photoinduction, but disappears 6 or more hours after irradiation. Postinduction spores whose germination is inhibited by 40 C treatment recover the ability to germinate after subsequent incubation at 25 C plus a second light treatment. The inhibition and recovery take place faster in postinduction spores than in preinduction spores. In addition, escape from 40 C inhibition is found in the postinduction phase but not in the preinduction phase. Temperatures lower than 25 C exert slow inhibition of both pre- and postinduction processes, and 30 to 35 C act to stimulate germination.In comparison with our earlier work with anaerobiosis and cycloheximide, the postinduction step inhibited by 40 C can be located shortly after the step inhibited by anaerobiosis but before the cycloheximide sensitive step.

Comparison of rat liver and Walker 256 carcinosarcoma tRNAs

The complete nucleotide sequences of both rat liver and Walker 256 mammary carcinosarcoma tRNAAsn reveal that they are identical except for the nucleotide present in the wobble position of the anticodon loop. The rat liver tRNAAsn contains the Q nucleoside, whereas the tumour tRNAAsn contains an unmodified guanosine. The tRNAs from both tissues also show significant quantitative differences in the chromatographic mobilities for isoaccepting species of tRNAAsp, tRNAAsn, tRNAHis and tRNATyr. In addition, chromatographic shifts upon cyanogen bromide treatment and analyses of the alkaline hydrolysates of these tRNAs demonstrate that those of tumour origin contain significantly less Q and Q nucleoside than their normal rat liver counterparts.

Lipoprotein lipase activator deficiency in very low density lipoproteins in rat nephrotic syndrome

Marked urinary loss of lipoprotein lipase activator in experimental rat nephrotic syndrome may be partly responsible for its deficiency in plasma very low density lipoproteins.

Chromatographic behavior of several mammalian tRNAs on acylated dihydroxyl-borate cellulose and Aminex A-28

Studies of the chromatographic behavior of mammalian tRNAs, from several sources, on acylated DBAE-cellulose indicate that species of tRNA Asn , tRNA Asp and tRNA His can be retained on this matrix, while species of tRNA Tyr, tRNA Asn and tRNA Asp are not retained. Treatment of total rat liver tRNA with cyanogen bromide and subsequent chromatography on Aminex A-28 columns demonstrated that these tRNA species might contain Q (or Q*) nucleoside. However, comparable studies of the tRNA isolated from Walker 256 rat mammary tumor tissue demonstrated that this tumor tRNA almost totally lacks the hypermodified nucleosides Q and Q*. In addition, we have found that at least the major species of rat liver tRNA Asn contains the Q nucleoside. These studies indicate that chromatography on the acylated DBAE-cellulose matrix, couple with the analytical ion-exchange chromatography of cyanogen bromide treated and untreated amino-acyl-tRNA can be a valuable technique for the determination of alterations in the Q (or Q*) nucleoside content of the tRNAs isolated from normal and tumor tissues.

Radioimmunoassay of human apolipoprotein CII. A study in normal and hypertriglyceridemic subjects

A specific, precise, and sensitive double-antibody radioimmunoassay for the measurement of human apolipoprotein CII (apoCII) was developed. ApoCII was labeled with (125)I (chloramine-T) and monospecific antibody was raised in rabbits. No appreciable cross-reactivity with apolipoproteins CI, CIII, AI, AII, low density lipoproteins, and lipoprotein-free plasma was observed. Lipoproteins containing apoCII displaced the standard curve in parallel. ApoCII measurement was not affected by pretreatment of plasma with tetramethylurea, ethanol-diethyl ether, or heating. Mean (+/-SE) plasma-immunoreactive apoCII in 47 normotriglyceridemic subjects was 51.8+/-3.2 mug/ml, generally comparable with previous estimates of its concentration by other methods. ApoCII levels in 9 subjects with type IIB lipoprotein pattern, 14 with the type IV lipoprotein pattern, and 5 with type V lipoprotein pattern were respectively, 89.9+/-4.6, 85.4+/-6.9, 132.8+/-21.0 mug/ml, all higher than normals (P < 0.001). Plasma apoCII and triglyceride concentrations correlated in normo- and hypertriglyceridemics (r = 0.36 and 0.58, P < 0.05). Plasma triglycerides correlated inversely with the fraction of total apoCII in very low density lipoprotein (VLDL)-free plasma (r = -0.75, P < 0.01). There was no correlation between plasma apoCII and high density lipoprotein cholesterol. In normotriglyceridemics, VLDL apoCII levels correlated with in vitro lipoprotein lipase (LPL) activator activities (r = 0.89, P < 0.01). In hypertriglyceridemic subjects the mean concentrations of apoCII per milligrams VLDL protein, LPL activator activity per milligrams VLDL protein, and LPL activator activity per micrograms VLDL apoCII were all lower than in normotriglyceridemics, P < 0.05. As plasma triglycerides and apoCII increase, apoCII is redistributed from high density lipoprotein to VLDL. However, the amount of apoCII per milligram VLDL protein and its LPL activator potency per milligram VLDL protein are reduced. These factors may contribute to impaired VLDL catabolism.

Immunological diagnosis of IgD paraprotein

IgD monoclonal peaks are relatively small, with broad bases, and are preferentially of gamma-1 or beta mobility. Often IgDgamma paraproteins can only be detected after proper dilution or reduction of the patient's serum. Assay for Bence Jones protein should not be neglected, and if it is present, the co-existence of IgD monoclonal gammopathy should be suspected.

Composition of HDL-2 and HDL-3 in familial hyperalphalipoproteinemia

The content and percent composition of cholesterol, triglyceride, phospholipids, and total proteins in HDL-2 and HDL-3 were quantitated in 5 women with familial hyperalphalipoproteinemia to determine if there are any distinctive characteristics of the high density lipoproteins in this heritable disorder. The 5 women with familial hyperalphalipoproteinemia (FHA) were compared to 4 normal women, with the groups being comparable in regards to age (40 +/- 3 and 37 +/- 5 years), total plasma cholesterol (202 +/- 9 and 188 +/- 16 mg/100 ml), triglyceride (75 +/- 12 and 95 +/- 19), and differing in levels of high density lipoprotein cholesterol (C-HDL, 84 +/- 6 and 61 +/- 3 mg/100 ml) respectively. Total cholesterol in the HDL-2 and HDL-3 fractions obtained by ultracentrifugation were 43.2 +/- 3.3 and 33.8 +/- 4.1 in FHA subjects, higher than total cholesterol in HDL-2 and HDL-3 in normals, 25.8 +/- 6.2 and 21.5 +/- 1.3 mg/100 ml, P less than 0.025. Total concentration of HDL-3 was higher in FHA than in normal subjects, respectively 222.4 +/- 22.6 and 149 +/- 7.2 mg/100 ml, P less than 0.025. Lipid-protein percent composition of HDL-2 and HDL-3 in FHA and normals was nearly identical, and polyacrylamide gel electrophoresis revealed no qualitative differences in band migration and appearance of the HDL-2 and HDL-3 fractions in normal and FHA subjects. In these women with FHA, there appears to be an increased concentration of normal HDL-2 and HDL-3.

High density lipoproteinuria in nephrotic syndrome

Intravenous administration of the aminonucleoside of puromycin produces the nephrotic syndrome (proteinuria, hypercholesterolemia, hypoproteinemia and edema) in rats. This model is very similar to human nephrotic syndrome caused by various disease states. The current study was designed to assess the nature of urinary lipoproteins in the urine of nephrotic rats, including studies related to the urinary loss of the "activator" apolipoproteins for the lipoprotein lipase-triglyceride interaction. Sprague-Dawley rats were given a single intravenous injection (10 mg/100 g) of puromycin aminonucleoside. Plasma and urine were collected before and 7, 18, 29, 36, and 53 days after injection of puromycin. Urine was fractionated in the preparative ultracentrifuge into density (d) fractions less than 1.006 (very low-density lipoproteins), d = 1.006-1.063 (low-density lipoproteins), and d = 1.063-1.210 (high-density lipoproteins--HDL). The cholesterol, triglyceride, phospholipid, and protein content of these fractions was analyzed. Lipoprotein electrophoresis was performed in agarose agar. Urine from normal and nephrotic rats was added to an in vitro system containing lipoprotein lipase and triglyceride. The free fatty acids (FFA) liberated were then measured as an index of urinary activator property on this system. Measurable urinary lipoproteins were present only on days 7 and 18 after induction of the nephrotic syndrome. Coelectrophoresis of these urinary lipoproteins with rat plasma revealed a single band having alpha- (HDL) electrophoretic mobility. The total mean protein content of day-7 urinary lipoproteins (64.3%) was greater than the content of plasma HDL (52.9%). The protein content of urinary lipoproteins also increased with time. When day-7 and day-18 postinjection urine at nephrotic rats was added to the lipoprotein lipase system, the hydrolysis of triglyceride yielded a mean of 0.320 and 0.235 muEq FFA/ml/20 min, respectively. Control rat urine yielded 0.030 muEq FFA/ml/20 min and 0.000 muEq FFA/ml/20 min 7 and 18 days after injection of normal saline, respectively. It is inferred that in this experimental model (1) high-density lipoproteins are probably excreted in the glomerular filtrate, (2) alterations in the composition of the excreted lipoproteins may occur during their passage through the nephron. The possibility that only a selective portion of the HDL spectrum is excreted into the glomerular filtrate cannot be excluded. It is suggested that the urinary or renal loss of this functionally important lipoprotein may contribute to the pathophysiology of hyperlipoproteinemia in the nephrotic syndrome.

Fungi isolated from asthmatic homes in the Taipei area

Indoor fungi in Taipei were surveyed during 1969-1974 using Sabouraud's agar plates. No remarkable yearly variation of fungal incidence was observed. The fungal population was found to be different from home to home. The dominant members were Aspergillus, Penicillium, Mycelia sterila, Oospora, Rhodotorula, Hormodendrum and yeasts. The order of frequency of fungi found indoors was quite different from that of outdoor fungi. The fungal spores were more numerous during summer months, and this trend was more apparent for Aspergillus, Oospora, Rhodotorula, and Hormodendrum. The kind and the incidence of fungi found in asthmatic homes were not different from those detected in non-asthmatic homes, except that in asthmatic homes there were greater numbers of fungi.

Regression of Metastases after Nephrectomy for Renal Cell Carcinoma

A case of an extensive renal cell carcinoma with temporary regression of pulmonary metastases is reported. The literature of similar reported cases is brefly reviewed.

Epidemiologic studies of eosinophilic meningitis in southern Taiwan

A study of the epidemiologic characteristics of 125 cases of eosinophilic meningitis or meningoencephalitis, probably caused by Angiostrongylus cantonensis, which occurred in southern Taiwan in 1968 and 1969 revealed a close association of the disease with the rainy season. In contrast to findings in other geographic areas, most such cases in this study occurred among children. A higher attack rate was observed among aborigines than among descendants of mainland Chinese. Most patients had eaten the giant African snail, Achatina fulica, prior to their illness and this mollusc was commonly found infected with third-stage larvae of A. cantonensis. However, in almost all instances the snail was eaten after it had been thoroughly cooked and examination of cooked snail meat revealed only dead larvae. It is suspected that patients became infected by inadvertently ingesting A. cantonensis larvae liberated when the snails were prepared for consumption.