PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “LUBRICATION”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 451 records · Page 25Linked to original sources
PubMed2001

Conditioning of hydrogel lenses by a multipurpose solution containing an ocular lubricant.

PURPOSE: The addition of the ocular lubricant hydroxypropyl methylcellulose (HPMC) to a multipurpose contact lens solution conditions the hydrogel lens surface. This investigation reports the clinical benefits to contact lens wearers and the improved physical properties of the solution with HPMC added. METHODS: One-hundred forty-seven subjects wearing a variety of hydrogel lenses used a multipurpose solution with and without addition of HPMC and were assessed for product comfort and preference. In the laboratory, conditioning by HPMC was demonstrated in fluid coating, dynamic contact angle, uptake of fluid on hydrogel lenses, and release of HPMC from lenses after soaking. RESULTS: Lens wearers reported the multipurpose solution with HPMC more comfortable, including measures relating to maintaining lens moisture over time. The multipurpose solution with HPMC produced a thicker and longer-lasting layer of fluid on hydrogel lenses and other plastics than other multipurpose solutions. HPMC was found to adsorb to both group 1 and 4 lens materials and release gradually, with detectable amounts releasing from the lens beyond 12 hours. CONCLUSIONS: The conditioning properties of the multipurpose solution with HPMC produce improved wetting of lenses and enhanced lens wearing comfort. Binding of HPMC to the lens surface and subsequent time-release is the probable mechanism for these benefits.

Contact Lens Solutions↗
PubMed2003

[The cracks of polycarbonate three-way stopcocks are enhanced by the lubricating action of fat emulsion of propofol].

The possible mechanism of cracks in the polycarbonate three-way stopcocks was investigated in the presence of propofol. We compared the crack formations with various insertion force and contact surface conditions. We could successfully reproduce overt cracks with leakage in three-way stopcocks when the male adaptors were strongly inserted and the contact surface was damped with propofol. With normal strength, no overt crack was observed at any liquid contact conditions. The male connector is more deeply inserted into the female three-way stopcock at the same insertion force when contact surface is damped with propofol. When propofol is present, the release force is not enhanced further while insertion force is increased. We conclude that the cracks in three-way stopcocks are enhanced by the increased expansion force by the lubricating action of propofol fat emulsion.

Anesthesia, Intravenous↗
PubMed2003

[Hydrocolloids and lubricating materials in the treatment of acute and chronic wounds].

The authors carry out a study on a dressing which associates hydrocolloids and a lubricating material, Vaseline, used on 28 patients who suffer from acute or chronic wounds having diverse etiologies. The authors evaluate the biological process through which each wound builds scar tissue, its tolerance, efficiency and degree of acceptance with results which are frankly positive. The data in this study for these parameters coincide with those of other research projects which have been carried out in France, Germany and the United Kingdom.

Acute Disease↗
PubMed2004

[Determination of the content of wear metal in lubrication oil by ICP-AES].

An analytical method for determining wear metal elements directly by ICP-AES was proposed in this paper. The optimum condition was selected. The Conostan S-21 and Conostan 75 (oil-base standard samples) prepared by multi-element oil-base reserved standard samples were applied to make calibration curve. Oil samples were diluted 5 times by kerosene. The contents of wear metals in lubrication oil were determined by ICP-AES. The relative standard deviation (RSD) of all elements was less than 1%. In addition, the authors represented the analytical efficacy of Leeman labs multi-track profile ICP, and its rapid and accurate characters of simultaneous multi-element measurement.

Calibration↗
PubMed2006

Injecting lubricant into the guiding catheter enables stent deployment.

BACKGROUND: The majority of percutaneous artery interventional failures is due to the inability to deploy stents in patients with tortuous arteries, fibrotic lesions and/or calcified plaque. Recent reports of lubricant-facilitated stent delivery have described the use of either dipping the stent into solution or applying the solution to the stent surface prior to insertion into the guiding catheter. This report demonstrates that injection of undiluted RotaGlide into the guiding catheter can better facilitate stent delivery into patients. Following unsuccessful stent placement, 2 cc of undiluted RotaGlide was injected into the guiding catheter by syringe with the undeployed stents just proximal to the lesion site. The stents were advanced and deployed without difficulty at the lesion site. This is the first report of RotaGlide being injected into the guiding catheter, resulting in what may be decreased friction of the buddy wire and/or stent. RotaGlide-facilitated stenting may be the best option when conventional techniques have failed.

Catheterization↗
PubMed1990

Disinfecting effect of a disposable lubricant during cystoscopy.

To study the disinfecting effect of the lubricant Instillagel for the urethra in children, bacteriologic tests of the urethra were performed immediately before and after cystoscopy in 100 children. In addition urine cultures were taken during and after cystoscopy. The culture of the urethra before cystoscopy was positive in 75 children. For 46 of these children the second culture after cystoscopy plus Instillagel appeared to be sterile while in 20 children a considerable reduction in the number of bacteria was found. Out of 92 children with an initially sterile urine culture, the culture of the urine voided immediately after the cystoscopy appeared to be contaminated in 2 while several weeks later an infected urine was found in 5 children. From this study we may conclude that during cystoscopy Instillagel has a good disinfecting effect for the urethra in children.

Child↗
PubMedDate not supplied

[Lubricant-free piston compressors for mechanized medical instruments].

Piston compressor without lubrication with air blow to packing rings by plunger, disposed in subpiston space, is recommended as the basic scheme of construction of a power supply unit for medical pneumatic tooling. The construction reduces a leak of the compressive medium, increasing the efficiency of a compressor and seal reliability.

Electric Power Supplies↗
PubMed1980

[Study of the disinfectant action of lubricants in transurethral electroresection].

The result of our examinations was that instillagel has a desinfecting effect in the urethra. This result is mathematically secured by means of the 2 I-test and highly significant. 95% of the preoperatively infected urethras were germ-free immediately after operation. This effect could not be proved in nifucin-gel-medicain as well as in urocomb. Using these lubricants all preoperatively infected urethras were also infected immediately after operation.

Anti-Infective Agents, Urinary↗
PubMedDate not supplied

[Combined action on the body of a mixture of the volatile products of lubricating oil thermal oxidative breakdown and of hypoxic hypoxia].

The experiments on white male mice have shown that the combined effect of different concentrations of mixtures of volatile products of thermooxidative decomposition of the lubricating oil 36/IKUA and hypoxia at altitudes 5,000; 7,000 and 8,000 m depends on the intensity of the combined factors. It is indicated that maximally allowable concentrations of the above mixtures in the space cabin atmosphere should be determined, taking into consideration the level of hypoxia.

Altitude↗
PubMed1995

Lubrication use in condom promotion among commercial sex workers and their clients in Ratchaburi, Thailand.

Condom promotion has been intensified in Thailand to prevent the spread of HIV. A water soluble lubricant (WSL) could be used to alleviate many unpleasant side effects of frequent condom use experienced by sex workers and their clients. This study was conducted to determine the efficacy of WSL use in preventing the side effects of condom use including condom breakage, and to assess the acceptance of WSLs within the sex-worker population. The results of this study showed that 83 (111) of the 134 sex workers reported use of the WSL provided during the study period and more than 95 per cent (106) expressed interest in employing the WSL regularly, saying that WSLs reduce unpleasant side-effects relating to frequent condom use. Also 70 per cent of them reported that the majority of their clients found using the WSL made condom use more enjoyable. A follow-up study showed that 57 per cent of the respondents were still using a WSL on a regular basis and all of them felt it reduced condom breakage. Therefore, WSL use should be an acceptable and useful method for alleviating problems associated with regular use of condoms within the sex-worker population. In addition, there is evidence that WSLs can reduce the incidence of condom breakage. Thus, WSLs could be valuable tools in condom promotion for AIDS control within this high risk population and their clients.

Adolescent↗
PubMed1994

Study of volatile noxious compounds composition during the use of lubricant-coolant fluids.

The aim of the study was the gas chromatography (GC) separation and mass spectrometric (MS) identification of volatile compounds mixture generating in the air of work environment when lubricant-coolant fluids (LCFs) are used. GC/MS method was used for determining mixture ingredients. Hydrocarbons, carbonil compounds, esters, oxiranes and aromatic amines were identified in test samples. When LCFs are used, monitoring of highly toxic substances (aromatic amines, carbonil compounds and oxiranes) makes the assessment of risk and exposure more complete.

Air Pollutants↗
PubMed1998

The use of sodium hyaluronate as a lubricant in brow suspension ptosis surgery using polyester fiber mesh.

Polyester fiber is used as an alternative to autologous fascia lata for brow suspension ptosis surgery. The authors found it difficult to pass the polyester compound through the submuscular plane during brow suspension surgery. They used sodium hyaluronate as a lubricant to aid the passage of polyester fiber mesh. In 14 cases of brow suspension surgery with polyester fiber mesh, the authors found sodium hyaluronate to be useful in reducing tissue resistance and without untoward effect.

Blepharoptosis↗
PubMedDate not supplied

Disposition and pharmacokinetics of a lubricant contaminant, 2,6-di-tert-butyl 4-nitrophenol, in grafted human skin.

Disposition and uptake/elimination profiles of topical 2,6-di-t-butyl, 4-nitrophenol (DBNP), the nitrated metabolite of an antioxidant additive of lubricant and hydraulic fluids was quantified in human skin grafted on athymic mice after a single topical 75 microg dose in corn oil. DBNP was quantified throughout the stratum corneum (SC), epidermis (E) and dermis (D) in punch biopsies collected from treated skin 0.5, 1, 2, 4, 8 and 24 h after application. SC samples were harvested from the treated skin with 20 adhesive discs. E and D were generated from the biopsy using a manual sectioning method. Detectable DBNP concentrations were measured in all skin compartments at all time points investigated. The Cmax of DBNP in SC was 1663 +/- 602 microg cm(-3), and approximately 30 and approximately 300 fold greater than the Cmax for E and D, respectively. Tmax occurred at 1.0, 0.5 and 1.0 in the SC, E and D, respectively. Over a 24 h interval (AUC0-24 h) there was 52 and 520 fold more DBNP in the SC than E and D, respectively. The elimination half-life of DBNP was 11 h from the SC and 9 h from both E and D. Thus, DBNP was quickly absorbed into the outermost layer of skin and established a steep concentration profile through human skin. The data are consistent with the vast majority of DBNP remaining on the surface (77%) or within human skin (15%) in vivo with only 0.2% of the DBNP dose quantified in the systemic blood circulation.

Adult↗
PubMed1989

The dermal carcinogenic potential of unrefined and hydrotreated lubricating oils.

Unrefined lubricating oils contain relatively high levels of polycyclic aromatic hydrocarbons (PAH) and have been shown to induce tumors in mouse skin. Exxon has developed a new method of refining these materials, a severe hydrotreatment process that is optimized for PAH removal. The specific objectives of the current study were to assess PAH reduction and then to evaluate directly the dermal carcinogenic potential of the materials that spanned the range of products produced by this method. The test samples included unrefined light and heavy vacuum distillates from a naphthenic crude oil, as well as the corresponding severely hydrotreated products. Two sets of samples were prepared to assess the effects of various operating parameters in the reactor. Additionally, positive (benzo[a]pyrene), negative (white mineral oil) and vehicle (toluene) control groups were included to assess the sensitivity and specificity of the bioassay. Each sample was applied in twice-weekly aliquots to the backs of 40 male C3H mice. In the analytical studies, significant reductions in the levels of several specific PAH were demonstrated. In the dermal carcinogenesis studies, the unrefined oils and the positive control induced tumors and also significantly reduced survival. None of the mice treated with severely hydrotreated oils or with the negative or vehicle controls developed skin tumors, and survival of these mice was not significantly different from the control. Thus, the data demonstrated that this new, severe hydrotreatment process was an effective means of converting carcinogenic feedstocks to non-carcinogenic products.

Animals↗
PubMed1991

Four-week inhalation exposures of rats to aerosols of three lubricant base oils.

Sprague-Dawley rats were exposed to aerosols of one of three base stocks used to formulate lubricating oils. These stocks were a solvent-refined oil (SRO), a hydrotreated and acid-washed white oil (WTO) and a severely hydrotreated and hydrocracked oil (HBO). Exposures were for 6 h per day, 5 days per week for ca. 4 weeks. There were four groups of rats for each study (10 per sex per group). Aerosol concentrations were ca. 0, 50, 210 and 1000 mg m-3 for each material; the mass median aerodynamic diameter was ca. 1 microns. Following the last exposure, all animals were sacrificed and necropsied. Samples were taken for serum chemistry, hematology, sperm morphology, weights of seven organs and histopathology on at least nine organs. Body weights and clinical signs were not affected by exposures. The only treatment-related changes were in the lung and associated lymph nodes. Both the wet weight of the lung and the dry/wet weight ratio increased in a concentration-related manner. Associated with the increased weight were accumulations of foamy alveolar macrophages, particularly in alveoli close to alveolar ducts. Mild infiltration by neutrophils was observed with WTO and SRO; thickened alveolar walls were noted with the highest concentration of HBO. These mild responses to exposures at very high concentrations indicate a low degree of toxicity for these aerosols.

Administration, Inhalation↗
PubMed1999

Articular cartilage superficial zone protein (SZP) is homologous to megakaryocyte stimulating factor precursor and Is a multifunctional proteoglycan with potential growth-promoting, cytoprotective, and lubricating properties in cartilage metabolism.

We have performed cDNA sequencing and homology analyses to elucidate the complete amino acid composition for a superficial zone protein (SZP) from human and bovine cartilage which has previously been shown to be a proteoglycan specifically synthesized by chondrocytes located at the surface of bovine articular cartilage and also some synovial lining cells. The results of this study indicate that cartilage SZP is homologous with a glycoprotein first described as the precursor protein of a megakaryocyte stimulating factor (MSF). Sequence comparisons and analyses indicate that (i) the amino acid composition of SZP is highly conserved between bovine and human species, (ii) SZP contains structural motifs at the N- and C-termini which are similar to those found in vitronectin and which may impart cell-proliferative and matrix-binding properties to the molecule, and (iii) SZP contains large and small mucin-like repeat domains composed of the sequences KEPAPTTT/P (76-78 repeats) and XXTTTX (6-8 repeats), respectively, which occur within a large central region of approximately 940 amino acids. The mucin-like domains are likely to be substituted with O-linked oligosaccharides which would impart lubricating properties to SZP which in part accumulates at the articular cartilage-synovial fluid interface. Additionally, we have shown that interleukin-1 inhibits the biosynthesis of chondrocyte SZP, while TGF-beta and IGF-1 increase its biosynthesis, and that in pathological (osteoarthritic) human articular cartilage SZP mRNA can be expressed as an alternatively spliced variant lacking exons 4 and 5 which encode a potential heparin binding domain. The occurrence of different SZP alternative splice variants and the differential expression of SZP in the presence of cytokines and growth factors suggest that SZP may play an important cytoprotective role by preventing cellular adhesion to the articular cartilage surface in normal cartilage metabolism. Modifications to the structure of SZP, coupled with inhibition of SZP synthesis during inflammation, may account for the attachment and invasion of pannus observed in inflammatory joint diseases.

Amino Acid Sequence↗
PubMed1996

Observations of scanning electron microscopy detected abnormalities of non-lubricated latex condoms.

To describe surface abnormalities found by scanning electron microscopy of non-lubricated latex condoms, thirty samples of 15 condoms were photographed at low (26-94x), medium (240-940x) and high (> 1000x) magnification. Each sample was initially scanned at low magnification to determine the presence and location of surface abnormalities. Photographs taken at medium and high magnification were of the area most representative of the abnormality. Nine samples (30%) were completely normal at all magnifications. Of the total viewed at low power, 18 (60%) were normal, 11 (37%) revealed ridging and 1 (3%) revealed melting. Of the total viewed at medium power, 14 (47%) were normal, 3 (10%) showed cracking, 2 (7%) showed melting or a combination of ridging and cracking, and 11 (37%) showed ridging. At high power, 10 (34%) were normal, 11 (38%) revealed either melting or a combination of two defects, 5 (17%) showed ridging, and 3 (10%) revealed cracking. Fifteen (50%) of the samples revealed a surface abnormality (cracking or melting) other than ridging. The majority of condoms viewed under scanning electron microscopy revealed surface abnormalities. The implication of the detected abnormalities needs further evaluations. While ridging may represent a minor abnormality associated with condom handling, multiple abnormalities or melting may represent a more significant atypicality.

Condoms↗