Correlation of freeze-fracture and scanning electron microscopy of epiphyseal chondrocytes

Summary Chondrocytes in epiphyseal cartilage were examined by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) using freeze-fracture techniques. Freeze-fracture replicas showed large numbers of fingerlike, 0.11–0.15 m diameter, projections from the chondrocyte surface, with numerous 95–180 Å diameter intramembranous particles associated with both the cell membrane surface and these projections. With SEM, these cytoplasmic projections were also obvious, but appeared collapsed into clusters of globular-shaped projections on the surface of the chondrocytes. With freeze-fracture techniques, in which shrinkage artifacts were essentially eliminated, the cytoplasmic projections were often seen in intimate contact with the extracapsular matrix. However, with chondrocytes prepared by both SEM and conventional TEM, there was evidence of shrinkage, the cytoplasmic projections having little contact with the extracapsular matrix. These findings show that the cytoplasmic processes are not artifacts of tissue processing and provide morphological evidence in support of the hypothesis that matrix vesicles are of cellular origin.Correlation of Freeze-Fracture and Scanning Electron Microscopy of Epiphyseal Chondrocytes     

Morphological and quantitative study of spirochetes in the feces of normal and infected SPF pigs during the incubation period of swine dysentery.

Spirochetes found in feces of normal and infected pigs during the eight days preceding the onset of the clinical signs of swine dysentery have been studied using electron and phase contrast microscopy. According to their dimensions, diameter, length and pitch, three morphological groups have been described: small, intermediate and large spirochetes. On the basis of their axial filaments arrangement, eight types have been observed. Compared to the control pigs, there was no increase in the total number of spirochetes in infected pigs, except at day 6 before the onset of clinical signs. However, infected pigs have shown a wide spectrum of different morphological types of spirochetes in comparison to control, uninfected pigs, which showed only the type "1-2-1" spirochete of axial filaments arrangement. This last type was predominant in infected swine during the entire incubation period as compared to other spirochete types described.     

Solitary Neurofibromas in and around the ear

Three cases of solitary Neurofibromas in and around the ear are reported.     

Characterization of bound phenthoate residues in citrus

The metabolism and fate of phenyl ring-labeled¹⁴C-phenthoate {O,O- dimethylS-[-(carboethoxy)benzyl] phosphorodithioate} was examined in the Valencia orange fruit with emphasis on the characterization of bound phenthoate residues in the fruit peel. The products recovered from the citrus fruit wash were unchanged phenthoate, phenthoate oxon, demethyl phenthoate, phenthoate acid, ethyl mandelate, and mandelic acid. The same products, with the exception of phenthoate oxon, were found in the acetone extract of the fruit peel. Enzymatic hydrolysis of the bound residue in the peel with-glucosidase, followed by acidic and basic hydrolysis gave ethyl mandelate as the major product, followed by mandelic acid, demethyl phenthoate and phenthoate acid. Phenthoate was metabolized and conjugated in citrus fruits into detoxication products.     

Costing depression and its management: an Australian study

OBJECTIVE: To examine the cost impact of referral to a Mood Disorders Unit (MDU), by comparing pre-service and post-service costs, and MDU and control samples. METHOD: We studied tertiary referral MDU patients and a control group of consultants' depressed patients, with the principal comparison intervals being: (i) 12 months prior to and (ii) 6 months following baseline assessment, with costs annualised to allow the impact of assessment and treatment recommendation to be determined. In addition, we assessed any 'personal cost' of depression. RESULTS: Following baseline assessment, MDU referrals showed a reduction in costs, while controls' costs increased, largely driven by contrasting directions in hospitalisation and social welfare costs. We identify variables associated with high and increased costs, including features of the earlier stages of the disorder, whether social welfare was received, diagnostic subtype and personality dysfunction, with multivariate analyses refining the variable sets. Self-report data indicated that patients judged the 'personal cost' of depression to exceed more formal cost parameters, so that to experience depression is itself depressogenic. CONCLUSIONS: This first Australian attempt to cost depression and its management in the clinical setting more provides a methodology for wider application in service evaluation studies rather than delivers an unequivocal answer to whether a specialist Mood Disorders Unit is cost efficient or not.     

In vitro combination treatment with perifosine and UCN-01 demonstrates synergism against prostate (PC-3) and lung (A549) epithelial adenocarcinoma cell lines.

PURPOSE: Antineoplastic agents often achieve antitumor activity at the expense of close to unacceptable toxicity. One potential avenue to improve therapeutic index might combine agents targeting distinct components of the same growth regulatory pathway. This might lead to more complete modulation of the target pathway at concentrations lower than those associated with limiting adventitious toxicities from either agent alone. The protein kinase antagonist UCN-01 is currently used in Phase I/II trials and has recently been demonstrated to inhibit potently PDK1. We have recently documented that the alkylphospholipid perifosine potently also inhibits Akt kinase (PKB) activation by interfering with membrane localization of Akt. This leads to the hypothesis that these two agents might act synergistically through distinct mechanisms in the PI3K/Akt proliferation and survival-related signaling pathway. EXPERIMENTAL DESIGN: The synergistic effects of UCN-01 and perifosine, on two cell lines (A-549 and PC-3), were examined using various long-term in vitro assays for cell growth, cell cycle distribution, clonogenicity, survival morphology, and apoptosis. Along with Western blotting experiments were performed to determine whether this synergistic combination of two drugs has significant effect on their downstream targets and on biochemical markers of apoptosis. RESULTS: After 72 h, perifosine at concentrations of 1.5 and 10 microM UCN-01 at 40 and 250 nM did not significantly affect the growth of PC-3 and A459 cells, respectively. However, in combination at the same respective individual concentrations (1.5 microM and 40 nM of perifosine and UCN-01, respectively, in PC-3 cells and 10 microM perifosine and 0.25 microM UCN-01 in the somewhat more resistant A549 cells), virtually complete growth inhibition of both the cell lines resulted. Supra-additive inhibition of growth was also demonstrated in independent clonogenic assays. Mechanistic studies in cell culture models suggest enhanced depletion of the S-phase population in cells treated by the combination. This correlated with enhanced inactivation of Akt along with activation of caspases 3 and 9 and poly(ADP-ribose) polymerase cleavage. Evidence of synergy was formally demonstrated and occurred across a wide range of drug concentrations and was largely independent of the order or sequence of drug addition. CONCLUSIONS: As the concentrations of UCN-01 and perifosine causing synergistic inhibition of cell growth are clinically achievable without prominent toxicity, these data support the development of clinical studies with this combination.