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PubMed1995

Pressure ulcers in the nursing home.

OBJECTIVE: To review the literature on the causes, epidemiology, prevention, and treatment of pressure ulcers in nursing homes and to summarize this information for clinicians caring for nursing home residents. DATA SOURCES: A MEDLINE search of English-language articles published between 1980 and October 1994 using the terms decubitus ulcer and elderly. References from identified articles were also examined. STUDY SELECTION: Articles were excluded if the title indicated that patients were not nursing home residents (unless data from nursing homes were limited or unavailable), that patients were not elderly, or that the ulcers were related to peripheral vascular disease or neuropathy. DATA EXTRACTION: Selected studies either contained original data or were meta-analyses. Prevalence studies were required to have an identifiable denominator; risk factor and incidence studies were required to have an identifiable cohort and a specified duration of follow-up. Preference was given to risk factors identified through multivariate analyses. Studies of preventive and therapeutic interventions were required to have an identifiable control group; preference was given to randomized controlled trials. DATA SYNTHESIS: Seventeen percent to 35% of patients have pressure ulcers at the time of admission to a nursing home, and the prevalence of pressure ulcers among nursing home residents ranges from 7% to 23%. Among high-risk patients, the incidence of pressure ulcers is estimated to be 14/1000 patient-days. Residents at higher risk for developing ulcers are those who have limited ability to reposition themselves, cannot sense the need to reposition, have fecal incontinence, or cannot feed themselves. Occlusive dressings are as effective and less costly than traditional wet-to-dry saline dressings for treating earlier stages of pressure ulcers. There is no consensus on the use of specialized beds in the nursing home for promoting the healing of advanced-stage ulcers or for reducing the incidence of ulcers in high-risk patients. Specific interventions should not detract from careful, total assessment and management of the patient. CONCLUSIONS: Pressure ulcers in the nursing home are common problems associated with significant morbidity and mortality. Because resident characteristics can identify residents likely to develop ulcers, preventive measures can be implemented early. Therapy for advanced stages of pressure ulcers is expensive and prolonged. Involvement of the physician with the multidisciplinary nursing home team is essential for prevention and therapy.

Aged↗
PubMed2005

Selective supercritical fluid extraction as a tool for determining the PCB fraction accessible for uptake by chironomid larve in a limnic sediment.

Selective supercritical fluid extraction (SFE) at 40 degrees C, 400 bar and 60 min was used to selectively remove bioavailable PCBs from a naturally contaminated limnic sediment. The extraction decreased the sediment concentrations of the nine studied PCBs by 54% (on average). Chironomid larvae were thereafter cultured in pre-extracted sediment as well as in untreated sediment to study the differences in uptake of PCBs in the two cultures. While the prevailing equilibrium partitioning (EqP) theory predicts a 54% decrease in PCB uptake by the chironomids in the pre-extracted sediment, with a maintained biota-to-sediment accumulation factor (BSAF), a decrease in PCB uptake by 91% was observed. For all investigated PCBs the BSAFs were on average 81% lower in the cultures with pre-extracted sediment than in the untreated systems. The data allowed for a calculation of the bioavailable fraction, which was estimated to 60%. This is very close to the 54% removed by selective SFE, demonstrating the possibility of using SFE as a tool to determine the bioavailable PCB fraction in a polluted sediment.

Algorithms↗
PubMed2001

Direct microextraction and analysis of rough-type lipopolysaccharides by combined thin-layer chromatography and MALDI mass spectrometry.

A rapid method for the microscale extraction of lipopolysaccharides (endotoxins, LPSs) from rough-type Gram-negative bacteria was developed using thin-layer chromatography (TLC) combined with improved conditions for LPS analysis by mass spectrometry. TLC of intact bacteria on silica gel plates in an appropriate solvent selectively extracted and separated their LPS components. The bands of molecular species were scraped from the plates after nondestructive visualization, directly mixed with matrix, and analyzed by laser desorption time-of-flight mass spectrometry. Lipids A and Re-type LPSs were analyzed after transfer to a membrane. Adding citric acid to the matrix gave greatly improved mass spectra. The system allows characterization of bacterial LPS at the microscale level and is equally well applicable to heterogeneous LPS and lipid A preparations (Escherichia coli lipid A and Bordetella lipopolysaccharides were used). The technique provides a rapid determination of the heterogeneity of unmodified preparations and the determination of the molecular weight of each separated component.

Chromatography, Thin Layer↗
PubMed1972

Chemical characterization of the proteins and glycoproteins of mouse liver plasma membranes solubilized by sequential extraction with aqueous and organic solvents.

1. A procedure for the stepwise fractionation of the proteins of mouse liver plasma membranes is described. 2. Of the membrane protein 20-25% was soluble in 50mm-sodium carbonate-bicarbonate buffer (pH9.7). This fraction contained a large number of proteins but only 1 major glycoprotein. It was low in sialic acid, amino sugars and phospholipid. 3. Extraction of the alkali-insoluble residue with aq. 33% pyridine solubilized an additional 30-35% of the membrane protein. The pyridine-soluble membrane components were enriched in sialic acid and glucosamine and it was shown that this procedure resulted in the selective extraction of glycoproteins. 4. Gel filtration in sodium dodecyl sulphate resolved the pyridine-soluble proteins into five fractions of decreasing molecular weight and an inverse relationship between molecular weight and sialic acid content was indicated.

Acrylates↗
PubMed1995

Stimulation of basal transcription from the mouse mammary tumor virus promoter by Oct proteins.

The steroid hormone-inducible promoter of mouse mammary tumor virus (MMTV) contains three overlapping sequences related to the consensus octamer motif ATGCAAAT. Basal promoter activity in the absence of hormone induction from a template in which all three octamer elements were mutated was decreased by two-to threefold in in vitro transcription assays. Oct-1 protein purified from HeLa cell nuclear extracts, as well as recombinant Oct-1 expressed in bacteria, recognized MMTV octamer-related sequences, as shown by DNase I footprinting. Furthermore, rabbit polyclonal antiserum directed against recombinant Oct-1 completely inhibited the formation of specific complexes between MMTV octamer-related sequences and proteins present in nuclear extracts of HeLa cells, indicating that Oct-1 is the major protein in HeLa nuclear extracts that recognizes octamer-related sequences in the MMTV promoter. In addition, depletion of Oct-1 from the nuclear extract by using Oct-1-specific antiserum or a sequence-specific DNA affinity resin decreased in vitro transcription from the wild-type MMTV promoter to a level identical to that obtained from a promoter in which all three octamer-related sequences were mutated. Addition of purified HeLa Oct-1 or recombinant Oct-1 to the depleted extract selectively increased transcription from the wild-type relative to the mutated promoter, demonstrating that Oct-1 transcription factor stimulates basal transcription from the MMTV promoter. A similar effect was observed when purified recombinant Oct-2 was added to the Oct-1-depleted extract, suggesting that Oct-2 may play an important role in MMTV transcription in B cells.

Base Sequence↗
PubMed1989

[Determination of saponosides from Panax ginseng C.A. Meyer. Comparison of official methods and HPLC].

Official methods for determination of ginsenosides of the French and Helvetic Pharmacopoeias have been compared with HPLC method. Sample preparation schemes used are those of monographs with conventional solvent extraction and solid phase extraction with a polar and a non-polar sorbents, respectively kieselguhr and C 18 octadecyl. Liquid-solid sample clean-up with C 18 cartridge is the most effective procedure. Prior HPLC method, an hydrolysis step of malonylginsenosides is necessary. Very selective extraction resulting in highly purified solution authorizes reliable and rapid colorimetric determination from ginseng saponosides.

Chromatography, High Pressure Liquid↗
PubMed1995

Actin, alpha-actinin, and spectrin with specific associations with the postacrosomal and acrosomal domains of bovine spermatozoa.

BACKGROUND: Characteristic membrane changes in spermatozoa culminating in acrosome reaction and sperm-egg fusion, and suspected involvement of actin-containing cytoskeleton in membrane changes in general, prompted us to investigate subcellular distribution of actin and actin-binding proteins in bovine spermatozoa subjected to various extractions which sequentially denude the sperm investments. METHODS: Spermatozoa were treated with either 1% SDS, 0.1% Triton X-100, 0.1% Hyamine, or 1 M MgCl2 or were sonicated. Immunostaining of actin, alpha-actinin, spectrin, and acrosin as well as electron microscopic analysis of extracted spermatozoa were carried out. RESULTS: Extractions caused evagination of the acrosomal lamina which retained focal contacts with the inner acrosomal membrane. Extractions further revealed lateral prongs at the anterior border of the postacrosomal sheath. Labeling for alpha-actinin and spectrin was localized in the acrosin-positive acrosomal lamina, neck, and principal piece, the latter containing also relatively extraction-resistant oligomeric or polymerized actin. In the postacrosomal area, actin was accumulated in the extraction-resistant posterior ring structure and anteriorly at the sites apparently related to the lateral prongs. Notably, spectrin reactivity was enhanced by MgCl2 in head, neck, and principal piece, and sonication abolished cytoskeletal immuno-reactivity in the head. CONCLUSIONS: Destabilization of membranes with selected extractions induces changes in the acrosomal lamina mimicking acrosomal vesicle formation. The lateral prongs and posterior ring structure, respectively, may serve as anterior and posterior anchors for the extraction-resistant post-acrosomal sheath. The lateral prongs may also be a merger zone for actin, alpha-actinin, and spectrin with important implication on sperm function. The latter two proteins may be involved in acrosomal vesicle formation. It is apparent that extractions have a significant effect on the detectability of sperm cytoskeletal elements.

Acrosome↗
PubMed1993

Identification of Streptococcus mutans antigen D as the HPr component of the sugar-phosphotransferase transport system.

Extraction of Streptococcus mutans with the detergents HECAMEG and lauroyl sarcosinate preferentially extracted antigen D, previously identified as a low molecular mass wall-associated protein. Western blotting with specific antisera was used to demonstrate that this antigen is the HPr component of the sugar-phosphotransferase transport system. Non-denaturing electrophoresis indicated that HECAMEG selectively extracted only one of the two forms of HPr. It is suggested that this form of HPr may have a specific cell surface location.

Antigens, Bacterial↗
PubMed1986

Extraction of plasma prorenin by human heart.

Arterial plasma prorenin underwent 58% extraction during one passage through the coronary circulation in eleven patients undergoing myocardial metabolic studies. Active renin and renin substrate were unaffected. Changes in renin and renin substrate concentrations were not detected across the enterohepatic, femoral, or renal vascular beds. This high degree of selective extraction of prorenin by the heart accounts for its proposed half-life. Prorenin could be a cardiotropic hormone.

Cardiac Catheterization↗
PubMed2003

Development of a sequential supercritical fluid extraction method for the analysis of nitrated and oxygenated derivatives of polycyclic aromatic hydrocarbons in urban aerosols.

A two-step supercritical fluid extraction (SFE) method has been developed for the analysis of oxygenated and nitrated polycyclic aromatic hydrocarbons (oxy- and nitro-PAHs, respectively) present in urban aerosol samples. The proposed SFE procedure first involves an extraction step using pure CO2 in order to remove the less polar compounds from the matrix and a second consecutive step using toluene-modified CO2. The oxy- and nitro-PAHs are obtained in the second step. Parameters affecting both collection efficiencies and the selective extraction of oxy- and nitro-PAHs in the second SFE step were optimised. Analysis of the extracts was performed using gas chromatography with electron-capture detection and coupled to mass spectrometry. The proposed SFE method was compared with a conventional extraction technique such as sonication and good agreement in the results was obtained. Nevertheless, clean up of sonication extracts was needed, whereas no purification was necessary for SFE extracts. The SFE method was applied to the analysis of oxy- and nitro-PAHs in urban aerosol samples and 9-fluorenone, 9,10-anthraquinone, 2-methyl-9,10-anthraquinone, benzanthrone, benz[a]anthracene-7,12-dione and 1-nitropyrene were identified at concentrations ranging between 15 and 364 pg m(-3).

Aerosols↗
PubMed1997

Trends in the referral and treatment of new patients at a free emergency dental clinic since 1989.

AIM: To investigate the changes in the pattern of new patient referral and treatment at a dental hospital emergency clinic since the introduction of the new dental contract in 1989. DESIGN: A prospective survey and review of clinical records. SETTING: The examination and emergency clinic at Cardiff Dental Hospital. SUBJECTS: 500 consecutive new patients attending the clinic in May/June in 1989, 1993, 1994 and 1995. MAIN OUTCOME MEASURES: Numbers of referrals; source of referral; geographical distribution of patients; registration with general dental practitioners; type of dental disease; treatment received. RESULTS: New patient attendances increased by 56% since 1989. Referrals from family doctors and dentists decreased while self-referrals increased. Self-referral by patients not registered with family dentists increased by 56%. Extraction of teeth was the commonest form of treatment in all years and increased by 72%. CONCLUSIONS: Numbers of patients attending for dental treatment at this setting increased substantially after 1989. Increasing numbers of these patients were inappropriately self-referred for treatment. Patients increasingly selected extraction of teeth as the primary treatment rather than restorative procedures. These changes appeared to be unrelated both to the severity of dental disease at presentation and to socio-economic status.

Adolescent↗
PubMed1993

Inhibition of ruminal cellulose fermentation by extracts of the perennial legume cicer milkvetch (Astragalus cicer).

Cicer milkvetch (Astragalus cicer L.) is a perennial legume used as a pasture or rangeland plant for ruminants. A study was undertaken to determine whether reported variations in its ruminal digestibility may be related to the presence of an antinutritive material. In vitro fermentation of neutral detergent fiber (NDF) of cicer milkvetch by mixed rumen microflora was poorer than was the fermentation of NDF in alfalfa (Medicago sativa L.). Fermentation of cicer milkvetch NDF was improved by preextraction of the ground herbage with water for 3 h at 39 degrees C. Such water extracts selectively inhibited in vitro fermentation of pure cellulose by mixed ruminal microflora and by pure cultures of the ruminal bacteria Ruminococcus flavefaciens FD-1 and Fibrobacter succinogenes S85. Inhibition of the cellulose fermentation by mixed ruminal microflora was dependent upon the concentration of cicer milkvetch extract and was overcome upon prolonged incubation. Pure cultures exposed to the extract did not recover from inhibition, even after long incubation times, unless the inhibitory agent was removed (viz., by dilution of inhibited cultures into fresh medium). The extract did not affect the fermentation of cellobiose by R. flavefaciens but did cause some inhibition of cellobiose fermentation by F. succinogenes. Moreover, the extracts did not inhibit hydrolysis of crystalline cellulose, carboxymethyl cellulose, or p-nitrophenylcellobioside by supernatants of these pure cultures of cellulolytic bacteria or by a commercial cellulase preparation from the fungus Trichoderma reesei. The agent caused cellulose-adherent cells to detach from cellulose fibers, suggesting that the agent may act, at least in part, by disrupting the glycocalyx necessary for adherence to, and rapid digestion of, cellulose.

Animals↗
PubMedDate not supplied

[The detection of tramadol and its metabolites in urine by chromatographic methods].

The authors recommend detecting a compound drug tramadol and its metabolites in urinary extracts by thin-layer, gas-chromatographic, high-pressure liquid, and other chromatographic methods. The metabolites were identified with due consideration for their fragmentation during an electron strike thereof and their trimethylsilyl derivatives, mobility during separation in a thin layer, and results of selective extraction at various pH. The proposed scheme of biotransformation includes the formation of products of O- and N- demethylation, N, N- and N,O-didemethylation and hydroxylation of the cyclohexane fragment. The Rf metabolite values and their mass spectra are presented. During gas chromatographic analysis at an evaporator temperature at least 250 degrees C tramadol undergoes thermal destruction with the formation of water molecules and cyclohexane structure.

Analgesics, Opioid↗
PubMed1992

The Na-K-Cl cotransporter of avian salt gland. Phosphorylation in response to cAMP-dependent and calcium-dependent secretogogues.

The effect of a cAMP-dependent secretogogue (VIP) on the phosphorylation of an endogenous, membrane-bound protein (pp170) was assessed in an intact cell preparation from the avian salt gland. The addition of VIP, in the presence of 100 microM isobutylmethylxanthine, resulted in a concentration-dependent increase in phosphorylation of pp170. This effect was rapid and transient with a 3-5-fold increase in phosphorylation occurring 1 min after the addition of VIP. Under similar incubation conditions, VIP stimulated a 4.6-fold increase in cAMP accumulation that paralleled phosphorylation. Exposure of cells to either forskolin or 8-Br-cAMP resulted in a 5-8-fold increase in the phosphorylation of pp170. The effect of forskolin was dose dependent with an EC50 similar to that for stimulation of secretion (35 nM). These results implicate an involvement for a cAMP-dependent protein kinase in the phosphorylation of pp170. The identity of pp170 was assessed utilizing a monoclonal antibody (Q3) directed against pp170. Q3 recognized a single 170-kDa band on Western blots of salt gland membrane protein. Immunoprecipitation of pp170 from salt gland cells resulted in the selective extraction of a single protein whose phosphorylation state was increased approximately 5-fold in response to carbachol or VIP. The identity of pp170 was established using two criteria. First, Q3 recognized affinity-purified Na:K:Cl cotransporter preparations from shark rectal gland membranes. Second, pp170 was selectively immunoprecipitated by monoclonal antibodies (J3, J4, and J7) that recognize different epitopes of the shark transport protein. These results suggest that pp170 is homologous to the shark rectal gland Na-K-Cl cotransporter, and thus the proteins may be functionally similar.

1-Methyl-3-isobutylxanthine↗
PubMed2005

Determination of parabens in pharmaceutical formulations by solid-phase microextraction-ion mobility spectrometry.

Solid-phase microextraction (SPME) coupled with ion mobility spectrometry (IMS) was used for the detection and quantitation of 4-hydroxybenzoate preservatives, methylparaben, ethylparaben, propylparaben, and butylparaben, in commercial pharmaceutical products. For the first time, SPME-IMS is described for the simultaneous detection, separation, and quantitation of multiple analytes in complex matrixes. The parabens are extracted from the samples using SPME, and the analytes on the fiber are heated by the IMS desorber unit and vaporized into the drift tube. The four preservatives differing only by a methyl group were separated in less than 18 ms. The analytical procedure was optimized for fiber coating selection, extraction time, sample pH, sample volume, ionic strength, and IMS conditions. Separation characteristics such as resolution, theoretical plates, and drift times of the parabens were also evaluated based on the direct interfacing of SPME to IMS. The conditions were tested using six over-the-counter topical products containing various combinations of preservatives. Analysis of the samples by SPME-IMS using benzyl paraben as an internal standard yields good comparison to an HPLC method, thereby reinforcing the applicability of this technique as a method for routine analysis. Limits of detection were 10 ng/mL for methylparaben and ethylparaben and 5 ng/mL for propylparaben and butylparaben. Good linearity range and reproducibility of less than 8% were obtained.

Calibration↗
PubMed1984

Hepatic clearance of rat plasma intestinal alkaline phosphatase.

The mechanism and route of clearance of intestinal alkaline phosphatase from plasma have been studied in rats to define the magnitude of hepatic extraction and biliary excretion of the enzyme. Plasma clearance, tissue distribution, and biliary excretion of enzyme were followed after intravenous administration of physiological amounts of 125I-labeled rat intestinal alkaline phosphatase. The plasma disappearance curve was biphasic; the initial phase was rapid, during which 50% of injected enzyme was selectively extracted by the liver over 5 min. Less than 4% of total hepatic radioactivity was excreted into bile over 80 min; this was shown by chromatographic analysis to be degraded enzyme only. Rapid clearance of enzyme could be significantly slowed by injection of large amounts of mannan or N-acetylglucosamine-bovine serum albumin, but not by desialylated fetuin, demonstrating that clearance was probably mediated by mannose/N-acetylglucosamine-specific receptors. It is concluded that, under physiological conditions, rat plasma intestinal alkaline phosphatase is rapidly cleared from the circulation by the liver. However, biliary excretion of undergraded enzyme is negligible, and a physiologically significant enterohepatic circulation seems most unlikely.

Alkaline Phosphatase↗
PubMed2004

A rapid in vitro polyomavirus DNA replication assay.

Traditionally, the Hirt extraction method, a multi-step, labor-intensive and time-consuming procedure, is employed to extract selectively low-molecular weight DNA for polyomavirus DNA replication analyses. DNA replication results obtained with this approach are often inconsistent between replicate samples. To increase the efficiency and reproducibility of the polyomavirus DNA replication assay, we compared the DNA quality and yield using Qiagen Spin Column technology and the Hirt extraction technique. CV-1 cells transfected with SV40 DNA were harvested at days 2, 4, and 6 post-transfection, and DNA was extracted using the Qiagen Spin Column and the Hirt extraction methods. Southern hybridization was performed using a (32)P-labeled linear full-length SV40 DNA probe. Viral DNA replication was quantitated using a BioRad phosphorimager, and results obtained with the two procedures were compared. Southern blot analysis revealed consistent and enhanced SV40 DNA recovery using the Qiagen Spin Column technology, and viral DNA replication over a 6-day period was reproducible among triplicate samples. In addition, Qiagen Spin Column technology reduced the time required to obtain good quality DNA for polyomavirus replication assays from 24 h to less than 3 h. Adoption of this extraction procedure will improve the determination of polyomavirus DNA replication activity, while reducing the investigator's exposure to and disposal of toxic organic compounds.

DNA, Viral↗
PubMed2001

S1 proteins C2 and D2 are novel hnRNPs similar to the transcriptional repressor, CArG box motif-binding factor A.

S1 proteins A-D are liberated from thoroughly washed nuclei by mild digestion with DNase I or RNase A, and extracted selectively at pH 4.9 from the reaction supernatants. Here, we characterized the S1 proteins, focusing on protein D2, the most abundant S1 protein in the rat liver, and on protein C2 as well. Using a specific antibody, McAb 351, they were shown to occur in the extranucleolar nucleoplasm, and to be extracted partly in the nuclear soluble fraction. We demonstrate that the S1 proteins in this fraction exist constituting heterogeneous nuclear ribonucleoproteins (hnRNPs), through direct binding to hnRNAs, as revealed by centrifugation on density gradients, immunoprecipitation, and UV cross-linking. In hnRNPs, protein D2 occurred at nuclease-hypersensitive sites and C2 in the structures that gave rise to 40 S RNP particles. By microsequencing, protein D2 was identified with a known protein, CArG box motif-binding factor A (CBF-A), which has been characterized as a transcriptional repressor, and C2 as its isoform protein. In fact, CBF-A expressed from its cDNA was indistinguishable from protein D2 in molecular size and immunoreactivity to McAb 351. Thus, the present results demonstrate that S1 proteins C2 and D2 are novel hnRNP proteins, and suggest that the proteins C2 and D2 act in both transcriptional and post-transcriptional processes in gene expression.

Amino Acid Sequence↗