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At least 199 records · Page 11Linked to original sources
PubMedDate not supplied

Detection of sexually transmitted diseases by urethral cytology, the ignored male counterpart of cervical cytology.

The detection of sexually transmitted diseases by urethral cytology was investigated in 270 men examined by urethral swabbing smears. Each sample was used to prepare a wet mount smear and smears for staining by the Papanicolaou, Gram and methylene blue techniques. A fifth smear was used for direct staining with fluorescein-conjugated monoclonal antibodies for the detection of Chlamydia trachomatis. The smears were examined for cytoplasmic and nuclear changes as well as for pathogenic organisms and inflammatory changes. Infections with Chlamydia trachomatis, Neisseria gonorrhoeae and human papillomavirus (HPV) produced distinctive cytologic patterns similar to those seen in cervicovaginal smears from women. The patterns in candidiasis, trichomoniasis and herpes simplex virus infection were not as diagnostic. Particularly noteworthy were the nuclear alterations, which appeared to be proplastic in HPV infection but retroplastic in Chlamydia infection. The results of this study indicate that urethral cytology would be an invaluable addition in diagnosing sexually transmitted diseases in men, particularly in the case of Chlamydia and HPV infections. The monomorphic structure of urethral columnar epithelium, as compared to the cervical epithelium, seems to result in a clearer and more constant response to pathogenic infections, as seen in the resulting smears.

Animals↗
PubMed1977

[Late reconstruction of the orbital floor and zygomatic prominence with a readily vascularized plastic].

An implant made from a new artificial substance "Proplast" consisting of polytetrafluoroethylene and carbon is suitable for the secondary treatment of fractures of the orbital floor and zygoma. Histomorphological studies in animal experiments show rapid vascularisation and tissue ingrowth, which lead to permanent fixation of the implant. Clinical experiments confirm its suitability for the correction of displacement of the eyeball and enophthalmos as well as in the re-establishment of the zygomatic arch. For cosmetic reasons a new operative approach through a combined cantho-conjunctival incision is recommended.

Biocompatible Materials↗
PubMed1987

Minisculptured ossicle grafts versus implants: long-term results.

The present study deals with 832 ossicular chain reconstruction procedures performed in 655 patients from January 1975 to December 1985. Homograft and autograft ossicles, intraoperatively minisculptured according to personal or traditional techniques, were used in 626 ears (75.2%). In the remaining 206 ears Plastipore or Proplast total or partial ossicular replacement prostheses were employed. The functional hearing results are evaluated as a function of length of follow-up, techniques used, and preoperative diagnosis. Short-term hearing gain is satisfactory and very similar for both ossicles and implants. Long-term observation however, shows, a progressive and systematic reduction of the postoperative hearing gain for both treatments. The long-term deterioration of hearing levels in ears receiving implants is more evident and dramatic than that observed in ears with ossicles. The difference is statistically significant. The causes of failure are evaluated based on both clinical data and findings at revision surgery.

Adolescent↗
PubMed1977

Bone mineral and surface charge.

A triple association has been observed between a high negative surface charge, bone morphogenetic activity, and in vitro recalcificaiton in implants of demineralized bone matrix. Proplast fills with bony tissue when implanted in the body and shows the same triple association. The higher the negative surface charge, the greater is the mass of new bone induced and the higher degree of mineralization when placed in a calcifying solution in vitro. Further investigations are necessary to determine whether in implants of demineralized bone, a high negative surface charge may cause the formation of discrete calcium deposits or whether it triggers the invading primitive cells to differnetiate and produce bone, or both.

Animals↗
PubMed1983

Cementless total hip arthroplasty.

The differences between prostheses fixed with and without cement are mainly in the design and nature of the surface implant. The shapes of the sockets to be implanted without cement show a wide variety: cylinder, square, conus, and ellipsoid with and without threads. The hemispheric shape, however, which was chosen for the acetabular component of the isoelastic hip joint, does not disturb the natural form and function of the hip joint since the outer surface is closely adapted to the original subchondral bone layer. The noncemented cup is secured by threads, pegs, screws, etc., and by ingrowth of bony tissue in the grooves of the surfaces. Most femoral stems are based on the self-locking principle. All prosthetic models incorporate attempts to increase the surface of the stem (ribs, wings, corrugations, rims, etc.). There is a tendency to use less rigid elastic implants instead of the well known rigid metallic prostheses. The aim is to overcome the problems of stress protection and stress concentration observed with rigid implants. For the biomechanical integration of an implant, the properties of the surface, especially macroporosity and microporosity, are important. Most European models of noncemented endoprostheses are based on macroporosity (porometal, madreporic, etc.). The increase in implant surface area achieved with macroscopic perforations and recesses is relatively minor compared with the possibilities offered by microporosity ("alumine fritée," Proplast, fiber-metal, etc.). The best indication for use of a cementless hip endoprosthesis is in revision arthroplasty. The lost bone stock is replaced by bone grafts, thereby creating a situation comparable with that of a primary arthroplasty. Clinical experience with noncemented hip endoprostheses is, to date, promising, although the observation time for most models is short.

Biocompatible Materials↗
PubMed1996

[WIll there ever exist the ideal auditive prosthesis for the reconstructive surgery of the middle ear?].

The AA. of the paper review the several materials used for the reconstruction of the middle ear ossicular chain. They inform about each material, including the auto- and homologous grafts of ossicles, cortical bone and cartilage. Palavit, Polyethylene-90, Teflon, metallic implants. Porous plastic materials: Proplast, Plastipore and Polycel. Bioactive ceramic prosthesis (ceramics of aluminium oxyde): Frialit and CORP. Bioactive vitroceramic prosthesis: Macor, Bioglass and Ceravital. Also bioactive of phosphate of calcium: Hydroxyapatite and Apaceram. Prosthesic material of nacre, coal-coal and Polymetacrylate (Ossiculoplast). The most important matter is to get an ear in the best conditions in order to accept the prosthesis, that is to say, a bed completely dry with no inflammatory clues in the tympanic cleft and with a correct functionalism of the Eustachian tube. The healthy ossicular rennants of the chain must be spared. The apatites, bioactive ceramica, are the prosthesis of the future owing to its similitude to the bone. Nevertheless will be difficult to obtain an absolutely inert material inside the middle ear, of the stability of the cleft is not secured.

Ceramics↗
PubMedDate not supplied

[Synthetic implants in the reconstruction of the ossicular chain].

Experience has revealed a higher rate of functional failure of biocompatible prostheses used in the surgical reconstruction of the middle ear than was reported initially. The cause of these failures was analyzed in a retrospective study of 135 patients who underwent middle ear reconstructive procedures: 47 of them involved implantation of plastic prostheses. Proplast or Plastipore, and had a sufficient follow-up. We evaluated the prosthetic material and middle-ear conditions for which they were implanted.

Cerebrospinal Fluid Otorrhea↗
PubMed1982

On the characterization of porosity in PTFE-carbon composite implant materials by mercury porosimetry.

Questions have been raised about the use of mercury intrusion porosimetry to measure interconnecting pore sizes and void volumes in relatively soft and flexible materials such as porous implant composites of PTFE and carbon fibers. We have studied the effect of precompression of one such commercial composite on the mercury intrusion curves which cover all pore diameters greater than about 16 microns, the range of interest for tissue ingrowth applications. Prior compression by a pressure 20% greater than that encountered by the material during a mercury intrusion experiment did not change the ensuing pore size distribution curve, as compared with a noncompressed sample. Deformation of the material at higher pressures sufficient to decrease the sample volume inelastically by 17, 33, and 67% changed the shape of the mercury intrusion curves significantly, indicating that this technique can be used to detect prior deformation of an "unknown" sample. In the undeformed material, less than 15% of the total void as measured by mercury porosimetry consists of interconnecting pores greater than 100 microns in diameter and more than 50% of the void volume is composed of pores less than 40 microns in diameter.

Biocompatible Materials↗
PubMed1997

Kinetics of accumulation of citrus tristeza virus RNAs.

Citrus tristeza virus (CTV), a member of the closterovirus group, is one of the more complex single-stranded RNA viruses. The 5' portion of its 19,296-nt, single-stranded RNA genome is expressed as an approximately 400-kDa polyprotein that is proteolytically processed, while the 10 3' open reading frames are expressed from 3'-coterminal subgenomic RNAs (sg RNAs). As an initial examination of the gene expression of this virus, we found that the kinetics of accumulation of genomic and sg RNAs and coat protein of the T36 isolate of CTV were similar in protoplasts of the natural host, citrus, and the experimental nonhost Nicotiana benthamiana. Newly synthesized genomic RNA was detected 2 days postinoculation and increased to a maximum at 3-5 days. The RNA complementary to the full-length virion RNA increased with similar kinetics, but at approximately one-tenth the concentration of genomic plus strands. Most of the abundant sg RNAs also accumulated in parallel to that of the genomic RNA. However, the smallest sg RNA, which corresponds to the p23 gene, increased earlier. The different sg RNAs accumulated in greatly differing amounts, in general with 3'-most sg RNAs accumulating to higher levels than 5' sg RNAs. However, some 3' sg RNAs (p13 and p18) accumulated to low levels. The two 3'-most sg RNAs (p23 and p20) accumulated to high levels approximately equal to that of the genomic RNA. The accumulation curve for coat protein paralleled that of its mRNA, suggesting that its regulation was transcriptional. Progeny virions from protoplasts were used to sequentially infect new protoplasts, serving as a potential source of virus that could evolve free from the genetic selection in intact plants for aphid transmission and movement.

Capsid↗
PubMed1986

Rheumatoid disease and related arthropathies. II. Surgical rehabilitation of the temporomandibular joint.

A new classification of four types of TMJ involvement is proposed to help orient and direct the medical and surgical treatment of patients with rheumatoid disease and related arthropathies. Clinical symptoms, radiographic findings, facial deformity features, treatment planning, and results are discussed, with case reports that illustrate each type. Interpositional polymer laminates, a new glenoid fossa prosthesis, and a metallic condyle are introduced for use in selected cases where erosion and destruction of the condyle, meniscus, and fossa area have produced significant TMJ dysfunction and occlusal-facial deformity.

Adolescent↗
PubMed1987

Retained alloplastic temporomandibular joint disk implants: a retrospective study.

The surgical treatment of intermediate- to late-stage temporomandibular joint disease often involves disk removal. In many instances, disks have not been replaced; long-term postsurgical findings of crepitation and osseous remodeling have been noted although subjective signs and symptoms have been few. Attempts to decrease the noises and bony changes, to enhance biologic resurfacing, and to prevent adhesions, recurrent pain, and dysfunction have prompted many surgeons to use various alloplastic materials to replace the disk, either in a planned permanent (retained) or a planned temporary (retrievable) manner. However, a certain degree of morbidity remains. This article reports clinical responses and radiographic findings in a series of patients who received retained alloplastic temporomandibular joint disk implants.

Adolescent↗
PubMed1990

Osteophytic reaction to a polytetrafluoroethylene temporomandibular joint implant. Report of a case.

Alloplastic disk substitutes of polytetrafluoroethylene (PTFE) used in the management of late stage temporomandibular joint disease have often been accompanied by morbid tissue reactions and resultant destructive changes. Numerous clinicians have reported cases of severe radiographic and clinical bony destruction and degeneration accompanied by marked foreign body giant cell reactions in the adjacent soft tissues. The case reported here demonstrates just the opposite event. Osteophytic enlargement of the lateral portion of the zygomatic arch and glenoid fossa, with adaptation to the contours of the implant, along with severe condylar osteophytosis, was diagnosed through tomographic and CT imaging and was confirmed at surgery.

Adult↗
PubMed1990

Dental implications in Ehlers-Danlos syndrome. A case report.

Ehlers-Danlos syndrome is an unusual disease entity afflicting many body systems. Temporomandibular joint dysfunction has been described in an isolated number of cases. Ensuing complications should be recognized and the treatment plan modified accordingly. The following is a case report and review of the literature.

Adult↗
PubMed1989

Induction of connective tissue by various alloplastic materials: an experimental study in rats.

The capacity of three alloplastic implant materials to induce connective tissue was tested on the backs of 19 rats. A standardized viscous sponge served as control material. The commercial implant materials studied were carbon fibre and polypropylene ligament prostheses and a sponge composite of polytetrafluorethylene polymer and graphite fibre. Quantitative biochemical analyses (DNA, RNA, hydroxyproline and hexosamines) were done at 3 and 10 d, and 3, 6 and 9 wk post-operatively. Histological studies were done at 3, 6 and 9 wk. During the follow-up all the materials, when implanted subcutaneously, showed some capacity to induce ingrowth of granulation tissue. However, according to both quantitative chemical analyses and histological studies, the inductive capacity was greatest in the control sponge and in the polypropylene ligament prosthesis. In contrast, chemical analyses showed that the amount of granulation tissue developing during the follow-up was least in the rats with carbon fibre ligament implants.

Animals↗
PubMed1994

Kent prosthesis.

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Granuloma, Foreign-Body↗