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Incorporation of polysaccharides into the walls of regenerating protoplasts of Candida albicans was followed in the presence of papulacandin B, tunicamycin and nikkomycin. With the first drug, chitin was incorporated normally whereas incorporation of glucans and mannoproteins was significantly decreased. Tunicamycin decreased incorporation of all wall polymers when added at the beginning of the regeneration process but blocked only mannan and alkali-insoluble glucan incorporation when added after 5 h. Nikkomycin inhibited chitin synthesis, and the walls formed by the protoplasts were enriched in alkali-soluble glucan. Pulse-chase experiments suggested that a precursor-product relationship between the alkali-soluble and alkali-insoluble glucans existed in the wall. The results obtained with the antibiotics were confirmed and extended by cytological studies using wheat-germ agglutinin labelled with colloidal gold and concanavalin A-ferritin as specific markers of chitin and mannoproteins respectively. The results support the idea that regeneration of walls by protoplasts occurs in two steps: firstly, a chitin microfibrillar skeleton is formed, and in a later step glucan-mannoprotein complexes are added to the growing structure. The chitin skeleton probably allows the orderly spatial arrangement of the other polymers giving rise to the regenerated cell wall.

The secretory response of somatotropic hormone (STH) to arginine hydrochloride stimulation (0.5 g/kg) was studied in 13 postmenopausal women. Eight showed evidence of osteoporosis, based on clinical and morphoradiological data and on metacarpal cortical thickness measurement, and five had normal bone mass. In addition, the response to levodopa (500 mg) was determined in four of the osteoporotic patients. Baseline STH concentrations in the osteoporotic subjects did not differ from those in the nonosteoporotic group, but the latter showed a significant increase over the former at 45, 60, 90, and 120 minutes after stimulation. Similar findings were obtained with levodopa stimulation. Without necessarily implying a cause-effect relationship, our data appear to support the hypothesis that the poor secretory response of STH may be to some degree responsible for the osteopenia observed during the climateric.

A study was made of 26 patients diagnosed as phase I reflex sympathetic dystrophy. In all of them, a bone:soft tissue uptake index was quantified by scintigraphic scanning before treatment and 3 months later. Eighteen patients were treated with 100 MRC units salmon calcitonin, followed by 500 mg elemental calcium 4 hours after hormone administration. The treatment was administered 10 days a month separated by intervals free of therapy. The other 8 patients were treated without interruption with 500 mg naproxen every 12 hours. In the group treated with calcitonin and calcium, the uptake index declined from 13.3 +/- 8.2 to 4.1 +/- 1.8 (p less than 0.001). The uptake index rose from 2.1.3 +/- 17.7 to 31.1 +/- 23.0 (NS) in the naproxen group. Using the Student t-test for paired samples to evaluate individual changes, a highly significant difference was reached (p less than 0.005) in the calcitonin-calcium group. The difference was also significant (p less than 0.01) in the naproxen group, but it was negative (t = 3.620). These results confirm the efficacy of treating reflex sympathetic dystrophy with calcitonin and calcium and the superiority of this treatment as compared with nonsteroidal anti-inflammatory drugs.

Osteocalcin synthesis is dependent on the influence of the renal vitamin D metabolite, 1,25(OH)2D3. This metabolite is an etiological factor in some hypercalciurias, and osteocalcin may thus be a parameter for discovering them. In turn, parathormone, which stimulates 1,25(OH)2D3 synthesis, is also implicated in the hypercalciurias. Mean molecular parathormone, osteocalcin, 24-hour calciuria and the calcium/creatinine and hydroxyproline/creatinine ratios were determined in urine samples obtained after a 12-hour fast from 18 patients with absorptive hypercalciuria and 11 patients with renal hypercalciuria out of a total of 62 patients with renal lithiasis. No changes were observed in osteocalcin or parathormone, indicating that neither is valid for the diagnosis of hypercalciuria. Significant differences were only found in the Ca/Cr ratio (p less than 0.001), which was higher (0.31 +/- 0.07 vs. 0.13 +/- 0.04 mg/mg) in renal hypercalciuria than in absorptive hypercalciuria. No changes in osteocalcin have been reported in the hypercalciurias, but variations in parathormone have been reported, therefore requiring further study and thought to understand the processes involved.

A case of oncogenous osteomalacia secondary to a fibrous malignant histiocytoma in a 31-year-old male is described. The patient also demonstrated a lupuslike anticoagulant. Clinical signs of osteomalacia preceded by 9 years those of the tumor, a feature occurring in only 8% of these malignancies. Surgical resection of the tumor and surrounding tissues was followed by a clinical improvement and a return to normal of serum phosphorus and tubular reabsorption of phosphate, though the lupuslike anticoagulant persisted. This first description of a fibrous malignant histiocytoma with associated osteomalacia and lupuslike anticoagulant makes compulsory the inclusion of these syndromes among those already described that may appear with this tumor.

Mannoproteins from cell walls of Saccharomyces cerevisiae synthesized at successive stages of the population growth cycle have been solubilized with Zymolyase and subsequently analyzed. The major change along the population cycle concerned a large size mannoprotein material; the size of the newly-synthesized molecules varied from 120,000-500,000 (mean of about 200,000) at early exponential phase to 250,000-350,000 (mean of about 300,000) at late exponential phase. These differences are due to modifications in the amount of N-glycosidically linked mannose residues, since the size of the peptide moiety was 90,000-100,000 at all growth stages and the level of O-glycosylation changed only slightly. After incubation of the purified walls with concanavalin A-ferritin and subsequent analysis by electron microscopy, labelling was localized at the external and internal faces of the walls. The middle space of these was labelled after digestion of the glucan network with Zymolyase, which demonstrate the presence of mannoproteins in close contact with the structural glucan molecules throughout the wall.

Modifications occurring in the plasma membrane and their relationship to newly synthesized microfibrils were examined in regenerating protoplasts of Candida albicans by freeze-fracture electron microscopy. Freshly prepared protoplasts showed no residual wall material, and long invaginations covered the surface of the plasma membrane. Analysis of the external face (E-face) of the plasma membrane showed a significant decrease in the number of intramembranous particles (IMP) in comparison with the original cells. After 40 min incubation in regeneration medium, newly synthesized microfibrils which seemed to originate from protrusions in the plasma membrane were observed. The plasma membrane showed important modifications with respect to IMP. After 3 h 45 min, the cells were covered by an abnormal wall which showed isolated fibrils partially embedded in the matrix material. The plasma membrane of these partially regenerated protoplasts was similar to that of original cells. After 8 h, regeneration of the protoplasts seemed to be complete as no differences from the original cells were detected in the plasma membrane or the wall. Calcofluor white altered the deposition of wall polymers during regeneration, but did not modify the plasma membrane of the protoplasts.

Two cases of late hypophosphatemic osteomalacia are described: a male aged 30 who had the disease since he was 22 and a woman of 23 who had the disease since she was 14. Both presented with myopathy and bone pain, and showed hypophosphatemia, hyperglycinuria, reduced tubular phosphate reabsorption (TPR), increased hydroxyprolinuria and normal iPTH and iCT values. Radiologically the male had no Looser's zones and the woman did. Bone biopsy confirmed hypophosphatemic osteomalacia. Both cases were treated with vitamin D and oral phosphate and no improvement was observed. When treatment with 25(OH)D3 was initiated, no improvement was seen and afterwards this was combined with treatment using 1.25(OH)2D3 and from this time on a clinical improvement of the myopathy became evident in both patients. In the woman, healing of the bone lesions occurred at the same time as that of the myopathy, whereas in the male the bone lesions became worse. Healing of the myopathy was only obtained when treatment with 1.25(OH)2D3 was begun. Both patients had reduced values of 2.3 erythrocytic DPG and low level of serum phosphorus when the myopathy was cured, which suggests a lack of effect of 2.3 DPG or serum phosphorus as a cause of the myopathy. Although this had been attributed to a deficiency in the function of 25(OH)D3, the response to 1.25(OH)2D3 and due to the effects of this metabolite on calcium transport in muscle, suggests that the myopathy which occurs in late hypophosphatemic osteomalacia is a result of deficiency or resistance to the muscular effect of this metabolite. We cannot explain the lack of bone healing in the man and further therapeutic studies are required.