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Biomedical subjects

G Smith

Publications and source records attributed to G Smith.

At least 73 records · Page 4Linked to original sources
PubMed2003

Gastric reflux and pulmonary aspiration in anaesthesia.

Although aspiration is a relatively rare event during anaesthesia, it represent an important cause of anaesthesia related mortality and also of ventilator associated pneumonia in intensive care unit. The incidence of aspiration is markedly increased after trauma owing to the risk of recent ingestion of food, depression of consciousness and airways reflexes, and gastric stasis induced by raised sympathoadrenal tone. The factors which contribute to the likelihood of aspiration include the urgency of surgery, airways problems, inadequate depth of anaesthetic, use of the lithotomy position, gastrointestinal problems, depressed consciousness, increased severity of illness and obesity. Factors that predispose to aspiration pneumonia are: a gastric content with a pH less than 2.5 and a gastric volume of 0.4 ml kg-1; a reduction in lower oesophageal sphincter tone; a reduction of upper oesophageal sphincter tone and a not coordination between the pharyngeal muscle and the upper oesophageal sphincter tone during swallowing; and a depression of protective airway reflexes. Methods to minimize regurgitation and aspiration involve control of gastric contents (preoperative starvation is the method universal accepted), application of cricoid pressure and control of the airways.

Anesthesia↗
PubMed2003

Head lice diagnosed in general practice in the West Midlands between 1993 and 2000: a survey using the General Practice Research Database.

The potential of the General Practice Research Database (GPRD) for communicable disease surveillance was explored using head lice as an example. All diagnoses of head lice and prescriptions for parasiticidal agents from 1993 to 2000 in the West Midlands were analysed. Diagnoses reached a peak of 28.2 per 1,000 patient years at risk and total prescriptions reached a peak of 27.1 per 1,000 patient years at risk in 1997. Malathion and permethrin were prescribed most often. The proportion of further parasiticidal prescriptions issued within 30 days of the initial prescription increased to a peak of 11.5% of prescriptions in 1997. The ratio of the same:different further prescriptions changed during the study period, reaching a high of 5:1 in 2000. These trends are mirrored by the Royal College of General Practitioners (RCGP) Weekly Returns Service and Prescribing Analysis and Cost (PACT) data. Use of GPRD provides additional insights into patient data, particularly on prescribing, that would not be available from other sources.

Adolescent↗
PubMed2003

Influenza and adult hospital admissions for respiratory conditions in England 1989-2001.

Influenza is recognised as a major cause of excess hospital admissions during winter months. This study sets out to quantify admissions related to influenza during the last twelve winters and to examine the importance of age. Total admission data for respiratory disorders in adults for England during the years 1989 to 2001 have been used. Weekly admission data were examined in five-year age bands. Influenza epidemics were identified from clinical incidence data in the community. Baseline admission levels were determined by averaging weekly incidence data from weeks in which there was no clinical evidence of influenza activity. Excess admissions were estimated from the difference between observed and baseline admissions after adjusting the baseline in each group and year for the secular trend. Estimates for all adults were consolidated from the five-year age bands. Bed occupancy was estimated by applying data on average bed stay to excess admissions in age- and year-specific groups. We estimated 2.7% of all respiratory admissions were related to influenza. Excess admissions were strongly age related. Of the 16,227 annual average excess, 52% occurred in persons over 75 years. The excess admissions account for an average 145,544 bed days annually, two thirds (69%) in persons over 75 years. Annual excess bed occupancy was highest in 1999/2000 (39,512) though 30,000 excess admissions per year is not unusual. Hospital admissions due to influenza remain a major problem for health service delivery particularly in elderly populations. Though robust programmes of vaccination are needed, vaccination by itself will not eliminate the impact of influenza on hospital admissions in winter.

Adolescent↗
PubMed2002

Comparison of the binding of [(3)H]nociceptin/orphaninFQ(1-13)NH(2), [(3)H]nociceptin/orphaninFQ(1-17)OH and [(125)I]Tyr(14)nociceptin/orphaninFQ(1-17)OH to recombinant human and native rat cerebrocortical nociceptin/orphanin FQ receptors.

Nociceptin/orphanin FQ (N/OFQ) is a 17-amino acid endogenous neuropeptide ligand for the nociceptin receptor (NOP). We have prepared a [(3)H]-labelled truncated N/OFQ peptide, [(3)H]N/OFQ(1-13)NH(2) and compared its binding characteristics with [(3)H]N/OFQ(1-17)OH and [(125)I]Y(14)N/OFQ(1-17)OH in membranes prepared from Chinese hamster ovary cells expressing the recombinant human NOP (CHO(hNOP)) and the rat cerebrocortex. [(3)H]N/OFQ(1-13)NH(2), [(3)H]N/OFQ(1-17)OH and [(125)I]Y(14)N/OFQ(1-17)OH binding to CHO(hNOP) was concentration dependent and saturable with receptor density (B(max)) and radioligand equilibrium dissociation constant (pK(d)) values (mean +/- SEM) of 1043 +/- 58 fmol/mg protein and 10.35 +/- 0.03, 1348 +/- 44 fmol/mg protein and 10.06 +/- 0.04, and 1169 +/- 76 fmol/mg protein and 10.45 +/- 0.06, respectively. In the rat, B(max) and pK(d) values for [(3)H]N/OFQ(1-13)NH(2) and [(3)H]N/OFQ(1-17)OH were 130 +/- 1 fmol/mg protein and 10.70 +/- 0.03, and 157 +/- 4 fmol/mg protein and 10.34 +/- 0.02, respectively. The binding of all radioligands was displaced by a range of peptide and non-peptide ligands. There was a strong correlation (r(2) = 0.92, P = 0.002) between pK(i) values estimated with [(3)H]N/OFQ(1-13)NH(2) and [(3)H]N/OFQ(1-17)OH. No such correlation was observed in comparison with the [(125)I]-labelled peptide (poor agreement with low affinity N/OFQ(1-9)NH(2), Dynorphin-A and Naloxone benzoylhydrazone). We suggest that [(3)H]N/OFQ(1-13)NH(2) may be a useful alternative to [(3)H]N/OFQ(1-17)OH.

Animals↗
PubMed2002

Characterisation of the non-peptide nociceptin receptor agonist, Ro64-6198 in Chinese hamster ovary cells expressing recombinant human nociceptin receptors.

Nociceptin/orphanin FQ (N/OFQ) is the endogenous ligand for the opioid receptor-like receptor or nociceptin receptor (NOP). We have compared a novel non-peptide NOP agonist Ro64-6198 with N/OFQ in a series of GTPgamma35S binding and inhibition of forskolin stimulated cAMP formation assays. GTPgamma35S binding assays were performed in membranes prepared from Chinese hamster ovary cells expressing the recombinant human NOP (CHOhNOP). cAMP inhibition studies were performed in whole CHOhNOP cells. Both Ro64-6198 and N/OFQ stimulated GTPgamma35S binding with pEC50 values(95%CL) of 7.61(0.18) and 8.58(0.21) respectively. Both Ro64-6198 and N/OFQ inhibited cAMP formation with pEC50 values of 8.45(0.9) and 9.28(028) respectively. In each assay Ro64-6198 and N/OFQ were full agonists. Ro64-6198 stimulation of GTPgamma35S binding and inhibition of cAMP formation was competitively antagonised by the NOP antagonists [Nphe1]NC(1 - 13)NH2 (10microM), J-113397 (100nM) and III-BTD (1microM) with pKB values of 7.04(0.34) and 6.29(0.10), 8.65(0.34) and 7.90(0.30) and 7.59(0.22) and 7.60(0.22) respectively. Despite the slightly reduced potency of Ro64-6198 compared with N/OFQ, by virtue of high selectivity and relative metabolic stability this molecule will be of considerable use in studies of the actions of the NOP.

Animals↗
PubMed2002

Is mild cognitive impairment bridging the gap between normal aging and Alzheimer's disease?

Mild cognitive impairment (MCI) is one label applied to cognitive dysfunction that is beyond normal aging but of insufficient magnitude to qualify for the diagnosis dementia. Various opinions exist about the proportion of people who fall in this boundary condition, the rate at which they will progress to a full dementia syndrome, and the nature and extent of cognitive impairment at the time of MCI diagnosis. There are at least four important dimensions along which studies of boundary conditions must be compared in order to understand the discrepant findings. The first is the population frame sampled to establish MCI cohorts. The second is the nature of memory complaints. The third and fourth respectively, are the type of memory assessment and number and type of other cognitive domains assessed to identify and follow these groups. The contributions of each of these dimensions to the diagnosis of MCI and it's outcome are discussed.

Aged↗
PubMed2002

How to test the safety of homemade antegrade colonic washout fluid?

Normal saline is commonly used for antegrade colonic washout enemas. The saline solution is usually made at home by adding measured quantities of common salt to tap water. The best method for the carers to check the concentration of salt in these homemade solutions has not been reported. Various concentrations of saline solutions were tested for specific gravity (SG) with an aquarium hygrometer and urine analysis sticks by two blinded independent observers. An aquarium hygrometer can read SG with an accuracy of 0.00046 for saline solutions made in tap water and 0.00051 for those made with sterile water. Urine analysis dipsticks sticks failed to achieve this accuracy. An aquarium hygrometer is a simple and reliable way to measure the SG of homemade saline solutions. Its use may avoid the problems associated with over- or under-concentration of salt in the antegrade enema solution.

Enema↗
PubMed2002

Energy recovery from grass using two-phase anaerobic digestion.

Municipal solid wastes are major sources of air, water and soil contamination. There is a need for alternative waste management techniques to better utilize the waste and minimize its adverse environmental impact. A two-phase pilot-scale bio-fermentation system was used to evaluate the feasibility of producing methane from grass waste, a major constituent of solid wastes. The bi-phasic system consists of a solid phase and a methane phase. Leachate is re-circulated through the solid phase until a desired level of volatile fatty acid (VFA) is accumulated in the leachate. The leachate is then transferred to the methane reactor where the VFA is converted to methane. The results showed that 67% of the volatile solids in the waste can be converted into soluble chemical oxygen demand in a period of six months. The system produced an average of 0.15 m3 of methane per kg of grass. The average methane concentration in the produced gas was 71%. A mathematical model was developed to estimate the methane and carbon dioxide concentrations in the gas phase as a function of reactor properties.

Biodegradation, Environmental↗
PubMed2002

Randomized controlled trial investigating the effect of transcervical papaverine and bupivacaine on postoperative analgesia following laparoscopic sterilization.

BACKGROUND AND OBJECTIVE: A critical factor that delays patient discharge following day-surgery is severe postoperative pain and the requirement for strong analgesics. Laparoscopic sterilization is a day case procedure and is associated with additional postoperative pain compared with diagnostic laparoscopy. This pain, associated with application of Filshie clips, may be ischaemic or spasmodic in aetiology. Papaverine relaxes smooth muscle, and the aim of the study was to investigate if papaverine would be effective in improving postoperative pain if administered directly to the Fallopian tubes. Bupivacaine is used commonly in day-surgery and so we compared the effect of this local anaesthetic with saline placebo. METHODS: Sixty-six ASA I-II females undergoing laparoscopic sterilization were entered into the prospective, randomized, double-blind, placebo-controlled clinical trial. They received intrauterine papaverine (30 mg) or bupivacaine (0.375% 30 mL) or normal saline (30 mL) via the transcervical route before application of Filshie clips. RESULTS: There were no significant differences in the postoperative period between the three groups in the number of patients needing analgesia in the first 60 min postoperatively, the time to first analgesia, the rescue analgesic or antiemetic consumption, the incidence of postoperative nausea and vomiting, and the sedation and visual analogue pain scores. CONCLUSIONS: From the data presented, we would not recommend routine transcervical administration of papaverine or bupivacaine for pain following laparoscopic sterilization.

Administration, Topical↗
PubMed2002

Effects of alginate hydrogels and TGF-beta 1 on human dental pulp repair in vitro.

The objective of this study was to investigate the use of alginate hydrogels to present either exogenous or endogenous transforming growth factor (TGF)-beta 1 to the dentin-pulp complex to signal reparative processes. Hydrogels were prepared, applied to cultured human tooth slices and the effects on tertiary dentinogenesis examined histologically. Both TGF-beta 1-containing and acid-treated alginate hydrogels, but not untreated hydrogels, upregulated dentin matrix secretion and induced odontoblast-like cell differentiation with subsequent secretion of regular tubular dentin matrix on cut pulpal surfaces. It is concluded that TGF-beta 1 can signal both induction of odontoblast-like cell differentiation and upregulation of their matrix secretion in the human dentin-pulp complex. Alginate hydrogels provide an appropriate matrix in which dental regeneration can take place and may also be useful for delivery of growth factors, including TGF-beta s, to enhance the natural regenerative capacity of the dental pulp.

Acids↗
PubMed2002

Characterization of film-coated aerosol canisters using electrochemical impedance spectroscopy.

Drug adhesion to the walls of an aerosol canister can be prevented/reduced by coating the canister with a hydrophobic polymer (e.g., a fluoropolymer). In this study, three batches of fluoropolymer-coated canisters were investigated by electrochemical impedance spectroscopy (EIS) and scanning electron microscopy (SEM). The EIS technique showed that only one of the batches presented as a monolithic, non-porous film. The other two batches were either partially porous or highly porous. Scanning electron micrographs showed evidence of cracks, within the films, but could not alone establish the porous nature of these defects. For the non-porous and partly porous films it was possible to use the EIS data to determine the approximate film thickness. Estimates of 2-4 microm were obtained for the mean film thickness. These values compared favorably with micrometer estimates obtained following acid dissolution of the aluminum canister. It remains to be seen whether the properties of the films (i.e., the porosity and film thickness, determined by EIS) translate to differences in drug adhesion. Nevertheless, the EIS technique was shown to be a powerful, non-destructive method that lends itself to the rapid analysis of batch-to-batch variation in film-coated canisters.

Aerosols↗
PubMed2002

Does the opioid-sparing effect of rectal diclofenac following total abdominal hysterectomy benefit the patient?

BACKGROUND: The aim of this prospective, double-blind, randomized, placebo-controlled clinical trial was to investigate the opioid-sparing effects of rectal diclofenac following total abdominal hysterectomy. METHODS: Forty ASA I-II patients, aged 20-60 yr, were randomized to receive identical-looking suppositories of either diclofenac 75 mg or placebo, twice daily. All patients were given a standardized anaesthetic, with intravenous morphine via a patient-controlled analgesia device and either diclofenac or placebo for postoperative analgesia. RESULTS: The median 24 h morphine consumption (interquartile range) was significantly higher (P=0.02) in the placebo group [59 (45-85) mg] than in the diclofenac group [31 (14-65) mg]. In comparison with the placebo group, there were significant reductions in total pain score in the diclofenac group at rest (P=0.04) and on movement (P<0.01). Total (SD) sedation score was significantly lower (P=0.04) in the diclofenac group [90 (73) mm] than in the placebo group [148 (89) mm]. Total (interquartile range) nausea score was significantly lower (P<0.01) in the diclofenac group [14 (0-53) mm] than in the placebo group [64 (30-109) mm]. There was no significant difference between the two groups of patients in episodes of vomiting or number of rescue antiemetics. CONCLUSIONS: Rectal diclofenac reduces morphine consumption, improves postoperative analgesia, and reduces the incidence of adverse effects such as sedation and nausea.

Administration, Rectal↗
PubMed2002

The analgesic effects of intraperitoneal and incisional bupivacaine with epinephrine after total abdominal hysterectomy.

UNLABELLED: The objective of our study was to see if incisional and intraperitoneal bupivacaine with epinephrine produces analgesia after total abdominal hysterectomy. Forty-six ASA physical status I and II patients received a standardized anesthetic, patient-controlled analgesia (PCA) morphine, and rectal paracetamol 1 g every 6 h. Patients were randomized to receive 50 mL of bupivacaine 0.25% with epinephrine 5 microg/mL or 50 mL of normal saline. Thirty milliliters and 20 mL of treatment solution were administered into the peritoneum and incision, respectively, before wound closure. Seventeen and 16 patients in the Placebo and Bupivacaine groups, respectively, completed the study. The reasons for withdrawal were PCA malfunction, PCA discontinued too early, nausea, chest infection, intraabdominal drain insertion, and protocol violation. There were no significant differences between the Bupivacaine and Placebo groups in age, height, weight, or duration of surgery. Pain on movement was significantly more intense in the Placebo group than in the Bupivacaine group on awakening. Morphine consumption (interquartile range) over 24 h was 62 mg (53-85 mg) in the Placebo group compared with 44 mg (33-56 mg) in the Bupivacaine group (P < 0.01). This significant difference was attributable to the larger morphine consumption in the Placebo group in the first 4 postoperative h. We conclude that a combination of intraperitoneal and incisional bupivacaine with epinephrine provides significant morphine-sparing analgesia for 4 h after total abdominal hysterectomy. IMPLICATIONS: A combination of intraperitoneal and incisional bupivacaine with epinephrine may be recommended because it provides significant morphine-sparing analgesia for 4 h after total abdominal hysterectomy.

Adult↗
PubMed2002

Expressed sequence tags for the chicken genome from a normalized 10-day-old white leghorn whole-embryo cDNA library. 3. DNA sequence analysis of genetic variation in commercial chicken populations.

Single nucleotide polymorphisms (SNPs) have emerged as a major class of DNA markers with the advantage of permitting the development of high-density genetic maps adequate for quantitative trait loci (QTL) identification by linkage-disequilibrium analysis. Here we describe results of a relatively high-depth survey of chicken broiler and layer populations for SNPs in targeted genomic regions of chicken expressed sequence tag (EST) sites. The sequences scanned, representing the composite sequence of 12 amplified fragments for a total of 6489 bp, were randomly distributed, occurring on six different chromosomes or linkage groups in the chicken genome. Although one of the genomic DNA sequences did not match the reference cDNA sequence, another contained an intron that separated two putative exons. The number of SNPs observed within each of the 12 EST-targeted genomic regions ranged from 0 to 10 for a total of 44 and a frequency of 0.7%. About 70% of the polymorphisms were shared between layer and broiler populations. The average heterozygosity within the populations ranged from 0.15 to 0.48, with the layer populations showing the higher heterozygosity. SNPs and oligonucleotides described will provide a resource for genetic analysis in commercial chicken populations. The data appear to indicate that the relative frequency of SNPs in the targeted regions scanned is higher than the frequency reported for any of the other regions scanned to date in other eukaryotic genomes. Additionally, the results suggest that the use of DNA pools may offer an efficient approach to SNP detection in chickens, as has been shown in other vertebrates.

Animals↗
PubMed2002

Neonatal alloimmune thrombocytopenia due to HPA-3a antibodies: a case report.

A healthy infant was born at term by elective cesarean section to a 32-year-old para 4, gravida 4, mother. Within 24 hours, the infant was noted to have fairly extensive bruising on the back and shoulders. A full blood count evaluation was remarkable for severe thrombocytopenia (platelet count of 29 x 10(9)/L). Other hematologic parameters were normal. Human leukocyte antigen (HLA) class-1 antibodies but not platelet-specific antibodies were detectable in the maternal serum using a commercial antigen-capture ELISA (GTI-PakPlus kit). Anti-HPA-3a antibodies, while weakly reactive in the monoclonal antibody immobilization of platelet antigens (MAIPA) assay in the immediate postpartum serum, were readily detectable using this assay in a sample taken 4 weeks later. Genotyping for human platelet antigens (HPA) 1-5 by the polymerase chain reaction technique with sequence-specific primers (PCR-SSP) revealed the infant's platelet genotype to be HPA-1a/1a, 3a/3b, while that of the mother was HPA-1a/1a, 3b/ 3b, consistent with a diagnosis of anti-HPA-3a neonatal alloimmune thrombocytopenia (NAIT). This case illustrates the increased sensitivity of the MAIPA technique for the detection of platelet-specific antibodies. We believe this to be the first serologically confirmed case of NAIT due to anti-HPA-3a to be reported in the republic of Ireland.

Journal Article↗