The use of micromachined surfaces to investigate the cell behavioural factors essential to osseointegration

OBJECTIVE: Although currently available implants can be used to achieve osseointegration under well-defined conditions, a greater understanding of cell behaviour is required to improve the designs and embark on actual tissue engineering.
MATERIALS AND METHODS: We employed micromachined substrata to investigate some of the main behavioural responses of osteoblasts from rat fetal calvaria to surface topography. In particular, confocal laser scanning microscopy (CLSM), differential interference contrast microscopy, time-lapse cinemicrography, immunofluo-rescence, digital radiography and image analysis were used to investigate cell adhesion, cell shape and cytoske-leton distribution, tissue organization, cell differentiation, and microenvironment.
RESULTS AND CONCLUSIONS A grooved surface permitted the attachment of more cells than a smooth one. Cell shape and cytoskeleton were strikingly influenced as early as 20 min after cell attachment, when the cytoskeleton begins to align with the topography. Some grooved surfaces appeared to promote osteogenesis in vitro as assessed by the production of bone-like nodules. Moreover, these nodules align with the topography in vitro , and preliminary results indicate that bone-like tissue also aligns with grooves when such surfaces are implanted in vivo.     

Bullous eosinophilic cellulitis (Wells'' syndrome) associated with Churg–Strauss syndrome

We report a patient with Churg-Strauss syndrome (CSS) with asthma, eosinophilia, nasal polyposis and ANCA-associated multisystem vasculitis, who's skin eruption started with erythematous urticarial-plaques followed by haemorrhagic bullae. Histology of the plaques revealed 'flame figures' in the dermis with no granulomatous or vasculitic process, consistent with the diagnosis of eosinophilic cellulitis or Wells' syndrome. The association of CSS and Wells' syndrome observed in this patient may have a common pathogenesis. CSS may induce Wells' syndrome by an unknown factor.     

Culture and origin of epithelium-like and fibroblast-like cells from porcine periodontal ligament explants and cell suspensions

A method was developed for preparing cell suspensions from the periodontal ligament of porcine primary molars. Culture of these isolated cells resulted in the growth of two morphologically distinct cell populations; one epithelium-like and one fibroblast-like. The plating efficiency of the cell suspension was estimated at about 0.02 per cent. Similar cell populations were also obtained using a simple explant technique. Autoradiographic examination of explants labelled with [H³]-thymidine indicated that DNA-synthesizing cells were first detectable between 18–30 hr after explantation. The most likely origin of the epithelium-like cells was the epithelial rests of Malassez. Some of the cells of fibroblast-like morphology that incorporated the label at the earliest times appeared to be located in the immediate vicinity of blood vessels. These findings are novel in that growth of cells from dissociated periodontal ligament, elucidation of the origin of monolayers derived from connective tissue cells of periodontal ligament, and cell culture of epithelium derived from this source have not previously been reported.     

Long-term follow-up of rural involuntary clients

A cohort of 72 persons who had entered a rural Oregon county's involuntary treatment system in 1979 through 1982 was followed for six years. While schizophrenia was the most frequent diagnosis, several other conditions were represented including adjustment disorders, organic mental disorders, and substance abuse. The majority (55%) of persons with organic mental disorders died as did 12% of the individuals with schizophrenia. The overall mortality rate was three times the expected figure (p=.002). During the follow-up period, only 39% of the initial cohort received treatment from a community mental health program whereas 28% were newly admitted (involuntarily) to a state mental hospital. Hospital recividism was most likely among individuals who had had prior involuntary treatment. At least in rural areas, the civil commitment system seems to serve both “infrequent” and “persistent” users. Infrequent users mainly have diagnoses of adjustment disorders and/or substance abuse. Persistent users chiefly have diagnoses of organic mental disorders, mood disorders, or schizophrenia. Modifying the involuntary treatment system to take account of this heterogeneous population's diverse needs is discussed.     

Low seminal zinc bound to high molecular weight proteins in asthenozoospermic patients: evidence of increased sperm zinc content in oligoasthenozoospermic patients [published erratum appears in Hum Reprod 1998 Jun;13(6):1750]

Total seminal zinc concentration, seminal zinc fraction bound to high molecular weight proteins (HMW-Zn%) and zinc content in spermatozoa were assayed in the ejaculates of 90 asthenozoospermic patients subdivided into two study groups: normoasthenozoospermics (group I: n = 50) and oligoasthenozoospermics (group II: n = 40). The zinc concentrations of patients were compared with those of a control group of donors showing normal semen parameters. All samples were also investigated for their sperm membrane functional integrity by the hypo- osmotic swelling test (HOS). The results showed normal total zinc concentrations but very low HMW-Zn% values (P < 0.001) in seminal plasma of the two groups of asthenozoospermic patients compared to the controls. Furthermore higher zinc amounts (P < 0.001) were measured in spermatozoa of oligoasthenozoospermic patients compared to group I and to the control group. Oligoasthenozoospermics also displayed a lower HOS score (P < 0.001) compared to the other two groups. These data suggest that the increased unbound seminal zinc could contribute to the decrease of sperm motility in normoasthenozoospermic and oligoasthenozoospermic patients. A further impairment in sperm motility could occur in the oligoasthenozoospermic patients where the increase of seminal free zinc was followed by a major zinc uptake by spermatozoa. The higher intrasperm zinc content in these patients could be a reflection of their low sperm membrane functionality.      

In-111-labeled leukocyte scintigraphy in suspected orthopedic prosthesis infection: comparison with other imaging modalities

When infection of prosthetic orthopedic implants is suspected, optimal management requires accurate confirmation or exclusion of infection. The authors retrospectively studied 98 patients with possible infection who underwent scanning with indium-111-labeled white blood cells (WBCs) and subsequently underwent surgery within 14 days. At surgery, 50 patients had infections, as determined by means of culture or histologic results. The diagnostic accuracy of In-111 scanning was compared with that of plain radiography, arthrography, three-phase bone scanning, and various clinical and laboratory findings classically associated with infection. Positive findings on In-111 WBC scans and elevated erythrocyte sedimentation rates were found to be the most predictive variables in the diagnosis of septic prostheses (P less than or equal to .001 and P less than or equal to .002, respectively). Likelihood ratio analysis more clearly demonstrated the superiority of In-111 WBC scanning, with positive and negative scans yielding likelihood ratios of 5.0 and 0.16, respectively.