Monoclonal antibodies to type D retrovirus (SRV-2)

Monoclonal antibodies (MoAbs) to the major gag core protein p27 and a viral protein p44 of type D retrovirus (SRV-2) were produced and used in the detection of SRV-2 antigens in infected Raji cells and in tissues from macaques with simian acquired immunodeficiency syndrome (SAIDS) and retroperitoneal fibromatosis (RF). Anti-p44 MoAb showed inhibition of syncytium formation by both SRV-1- and SRV-2-infected Raji cells.     

Ultrastructure of carotenoid deprivation in photoreceptors of Manduca sexta: myeloid bodies and intracellular microvilli

Summary The ultrastructural effects of carotenoid (vitamin A) deprivation were studied in the adult photoreceptors of the tobacco hornworm moth Manduca sexta. Moths were reared on a deprived diet, which lacked the carotenoid sources of the photopigment chromophore, 3-hydroxy retinal, or on a control, fortified diet, containing ample carotenoid. The latter supported normal levels of visual function, whereas visual pigment and sensitivity were reduced by at least 3 log units in moths reared on the deprived diet. Myeloid bodies, massed cisternae of hypertrophied smooth endomembrane, filled the cytoplasm in the receptors of deprived animals. The myeloid bodies assumed various configurations that included lamellate stacks of parallel cisternae, and tubular networks in a paracrystalline form. Freeze-fracture preparations of myeloid membranes revealed a high density of P-face particles. Vacuoles containing microvilli similar to those of the rhabdomere were also present in deprived photoreceptors. We suggest that the elaboration of smooth endoplasmic reticulum as myeloid bodies in chromophore-deprived photoreceptors may stem from the hypertrophy of a biochemical system for processing the chromophore or the interruption of the intracellular pathway that normally carries visual pigment to the rhabdomere.     

Citric acid excretion and precipitation of calcium citrate in the rhizosphere of white lupin (Lupinus albus L.)

Abstract. White lupin ( Lupinus albus L.) was grown for 13 weeks in a phosphorus (P) deficient calcareous soil (20% CaCO₃, pH(H₂O)7.5) which had been sterilized prior to planting and fertilized with nitrate as source of nitrogen. In response to P deficiency, proteoid roots developed which accounted for about 50% of the root dry weight. In the rhizosphere soil of the proteoid root zones, the pH dropped to 4.8 and abundant white precipitates became visible. X-ray spectroscopy and chemical analysis showed that these precipitates consisted of calcium citrate. The amount of citrate released as root exudate by 13-week-old plants was about 1 g plant⁻¹, representing about 23% of the total plant dry weight at harvest. In the rhizosphere soil of the proteoid root zones the concentrations of available P decreased and of available Fe, Mn and Zn increased. The strong acidification of the rhizosphere and the cation/anion uptake ratio of the plants strongly suggests that proteoid roots of white lupin excrete citric acid, rather than citrate, into the rhizosphere leading to intensive chemical extraction of a limited soil volume. In a calcareous soil, citric acid excretion leads to dissolution of CaCO₃ and precipitation of calcium citrate in the zone of proteoid roots.     

Effect of nutritional copper deficiency on carrageenin edema in the rat

The effects of nutritional copper deficiency on carrageenin edema in the rat were investigated with emphasis on studying the correlation between the degree of copper deficiency and the degree of edema. Carrageenin paw edema in both copper-sufficient and copper-deficient groups of rats was compared after either 20, 40, or 60 d on respective diets. The degree of copper deficiency was quantitated by analyzing total copper concentrations in a number of tissues. Other copper dependent parameters were also determined. Results indicated that: (1) although copper sufficient rats showed relatively little change in the degree of edema, copper-deficient rats showed a steady and significant increase in edema from d 20 to 40 to 60; (2) paw edema in copper-deficient animals was highly and negatively correlated to the concentrations of copper in the liver; the correlation with liver Cu,Zn-superoxide dismutase activity, however, was inconsistent; (3) paw edema was not correlated either to copper concentration in tissues other than liver or to plasma ceruloplasmin activity; and (4) aggravation of carrageenin edema in copper-deficient animals seemed to be mediated via an as yet unknown secondary effect of copper deficiency.     

Renin-positive granulated Goormaghtigh cells

Summary It is difficult to distinguish between Goormaghtigh cells (G-cells) and media cells of the glomerular arterioles at the border of the Goormaghtigh cell field. Consequently, it has been unclear whether renin-positive G-cells are normally present and also whether renin-producing cells are recruited from the pool of renin-negative G-cells upon stimulation of the renin-angiotensin system (RAS). In the present study, immunohistochemical and electron-microscopic experiments have been carried out on serially sectioned kidney biopsies from four patients with pseudo-Bartter syndrome. The results strongly suggest that with longlasting stimulation of the RAS all renin-negative (secretory resting) G-cells are ultimately converted into renin-producing granular cells.Synonymous with extraglomerular mesangial cells     

N-15 in vivo NMR spectroscopic investigation of nitrogen deprived cell suspensions of the green alga Chlorella fusca

The possibility to apply N-15 in vivo NMR spectroscopy to study algal N-metabolism has been investigated. N-15 labelled cells of the green alga Chlorella fusca, subjected to nitrogen starvation and N-14 labelled cells supplied with K¹⁵NO₃ after prolonged nitrogen starvation were monitored by N-15 in vivo NMR spectroscopy at different times after the change in their nitrogen supply. During 20–40 min, necessary for the acquisition of 1 spectrum, the cells were under dark anaerobic conditions, but the relative amounts of the metabolites detected did not change. Signals from 2 acid amides, from the side chain nitrogens of arginine and lysine, from prolin as well as 4 signals from α amino groups of amino acids were detected. Besides two signals not yet reported in the literature were found. They may be due to amino compounds, but not to amino acids. The amount of free amino acids in the cells increases not only upon resupply of nitrogen starved cells with nitrate but also during the first hours after nitrate depletion. The spectra obtained from N-15 labelled autospores show that N-15 in vivo NMR spectroscopy can be applied to the investigation of N metabolism of the cells.     

The effect of a pattern in palmar interdigital II on a-b ridge count in black and white Down syndrome cases and controls

An unconfirmed study by Fang (Ph.D. thesis, Univ. of London, 1950) in Britain showed that individuals with Down syndrome had lower total a-b ridge counts in palmar Interdigital area II (ID II) than a group of controls. This study compares 603 white Down syndrome cases and 93 black Down syndrome cases with 668 white and 402 black controls. Our results confirm those of Fang in that the Down syndrome cases in both racial groups had lower total a-b ridge counts than their respective controls. In addition, the black controls and Down syndrome cases had lower a-b ridge counts than their white counterparts. The mean a-b ridge count was significantly lower in individuals with a pattern in ID II compared to individuals without a pattern in ID II in both the Down syndrome and control groups. Some of the lower a-b ridge counts in the Down syndrome samples can be accounted for by the fact that there is an increased frequency of a pattern in ID II in Down syndrome cases. Both Down syndrome and normal individuals who had a pattern unilaterally had a lower than expected a-b ridge count on the contralateral hand that did not have a pattern. There was a tendency also for increased asymmetry in Down syndrome cases with a pattern in ID II.     

Successful treatment for perinephric abscess with recombinant human granulocyte colony-stimulating factor following nephrectomy in a patient of myelodysplastic syndrome: A case report

The 35-year-old man with myelodysplastic syndrome (MDS) and granulocytopenia with dry cough and high fever was eventually found to have a left perinephric abscess ofStaphylococcus aureus. He underwent left nephrectomy and drainage of perinephric space in conjunction with appropriate antibiotics. However, because of persistent granulocytopenia,Staph. aureus never cleared up with formation of only poor granulation. Recombinant human granulocyte colony-stimulating factor (G-CSF) was added to the above treatment leading to prompt improvement in granulocytopenia and emergence of the good granulation tissue. G-CSF will probably become one of the important agents in treating MDS with granulocytopenia.     

Cryptococcus neoformans: A central nervous system isolate from an AIDS patient that is rhinotropic in a normal mouse model

A strain of Cryptococcus neoformans that was isolated from the cerebrospinal fluid of a human diagnosed as having acquired immunodeficiency syndrome (AIDS), and that produced cutaneous lesions in experimentally infected, normal mice is described. Although no unusual cutaneous manifestations were noted in the patient's records, this isolate of C. neoformans proved to be dermotropic when injected intravenously into CD-1 mice. The LD₅₀ at 28 days post infection ranged from 3.6–7.5×10⁵ cells per mouse, and in vitro growth rate studies demonstrated that this isolate grew well at 35 °C and at 37 °C, but did not grow at 40 °C and higher. This isolate was rhinotropic producing large granulomatous lesions in the nasal tissues. Other cutaneous tissues affected were the periocular tissues, ears, feet and tail, although the granulomas were nodular in structure and less necrotic than the nasal lesions. The brain, lungs, liver, kidneys and spleen also were culture positive for C. neoformans. Histopathologically, each affected tissue examined had large densities of yeast cells and a chronic, granulomatous host response. Animals surviving the infection appeared to develop a commensal-type relationship with the infective yeast. This is the first report of an isolate of C. neoformans from an AIDS patient that has caused cutaneous manifestations in an animal model. The model described in this report may be useful for elucidating pathogenic mechanisms of cryptococcosis, particularly cutaneous manifestations of the disease.