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Biomedical subjects

A Davies

Publications and source records attributed to A Davies.

At least 127 records · Page 7Linked to original sources
PubMed1996

2500 Outpatient diagnostic hysteroscopies.

OBJECTIVE: To evaluate the feasibility and acceptability of outpatient diagnostic hysteroscopy. METHODS: The outcome of 2500 consecutive outpatient hysteroscopies was analyzed. Cervical dilation was performed when necessary and local anesthesia was not administered routinely. Endometrial biopsy and minor hysteroscopic procedures were carried out when indicated. Findings and outcome were compared according to patient characteristics. RESULTS: The most common indication for hysteroscopy was abnormal uterine bleeding (87%). Hysteroscopy was performed successfully in 96.4%, and a complete view of the uterine cavity was obtained in 88.9%. Local anesthesia was used in 29.8% and was associated with the need for cervical dilation; both local anesthetic use and cervical dilation were significantly more often required in nulligravid, nulliparous, and postmenopausal women. Intrauterine pathology was diagnosed in 48%, the highest incidence being found in those 50-60 years old (53.7%). The presence of fibroids was the most common abnormality (24.3%) but was seen in only 6.8% of women older than 60 years. Conversely, the incidence of endometrial polyps increased with age, up to 20.5% in women over 60 years. Endometrial biopsy was performed in 68% and produced adequate tissue for histologic examination in 83.7%. Endometrial hyperplasia or carcinoma was detected in 1%. One hundred sixteen women (4.6%) underwent a minor hysteroscopic procedure. CONCLUSION: Outpatient diagnostic hysteroscopy is both feasible and acceptable in the overwhelming majority of cases, with a high detection rate for intrauterine pathology. This procedure may become as routine in the 21st century as D&C has been in the 20th.

Adult↗
PubMed1996

Rhodopsin, Gq and phospholipase C activation in cephalopod photoreceptors.

We present characterization of the rhodopsin, Gq and phosphatidylinositol-specific phospholipase C (PLC) from the signal transduction pathway of cephalopod photoreceptors. Cephalopod rhodopsins are unique in possessing a C-terminal extension of proline-rich repeats, and they have a strong tendency to form ordered arrays. Two-dimensional arrays of a full-length and C-terminally-truncated cephalopod rhodopsin have been obtained. The C termini appear to cluster the rhodopsins into small groups. An AlF4(-)-activated Gq alpha subunit has been isolated and shown to activate a partially purified PLC beta. This 130 kDa PLC, isolated by absorption on heparin agarose, showed a specific activity of 195 nmol of phosphatidylinositol 4,5-bisphosphate hydrolysed per milligram of protein per minute in the presence of 1.6 microM free calcium.

Animals↗
PubMed1996

Hysteroscopy in women with abnormal uterine bleeding on hormone replacement therapy: a comparison with postmenopausal bleeding.

OBJECTIVE: To determine the role of outpatient diagnostic hysteroscopy in patients with abnormal uterine bleeding (AUB) on hormone replacement therapy (HRT) and to contrast this with a control group of women presenting with postmenopausal bleeding. DESIGN: Comparative observational study. SETTING: Outpatient hysteroscopy clinic in a university hospital. PATIENTS: Three hundred ten patients undergoing outpatient hysteroscopy. INTERVENTIONS: Outpatient diagnostic hysteroscopy with endometrial biopsy when indicated. MAIN OUTCOME MEASURES: Hysteroscopic findings, need for cervical dilatation and local anaesthesia, correlation between hysteroscopy and histologic diagnosis. RESULTS: There were 157 (7.1%) patients with AUB on HRT and another 153 (6.9%) with postmenopausal bleeding out of 2,203 outpatient hysteroscopies. Hysteroscopy was successful in 97% and 92% of patients, respectively, and intrauterine pathology was diagnosed in 46.7% and 39.7% of these cases. Functional endometrium was noted significantly more often with HRT and endometrial atrophy with postmenopausal bleeding. Overall, local anesthesia was used in 126 (40.6%) and shown to be associated significantly with the need for cervical dilatation. Endometrial biopsy was attempted in 125 (80%) and 119 (78%) patients in the study and control groups, but was unsuccessful significantly more often with postmenopausal bleeding (38.7%) versus 16%). There were six cases of endometrial carcinoma, all in the control group. CONCLUSION: There is a high incidence of intrauterine abnormalities in women with menstrual symptoms while taking HRT, but the pathology differed from those with postmenopausal bleeding. As focal lesions are found commonly in such patients, their detection by diagnostic hysteroscopy should improve compliance with HRT as it would allow individualization of treatment.

Biopsy↗
PubMed1996

Antinociceptive actions of intrathecal xylazine: interactions with spinal cord opioid pathways.

We have studied rats with chronically implanted subarachnoid catheters. Xylazine, an alpha 2 adrenoceptor agonist, was injected intrathecally and nociceptive thresholds measured at two skin sites: the tail and the neck. Intrathecal xylazine (dose range 24.3-389 nmol) produced increases in electrical thresholds for nociception in the tail without any change in the neck; this observation suggested that the antinociceptive action of this drug was confined to the caudal part of the spinal cord responsible for tail innervation. The magnitude of this effect was dose-dependent. Tail flick latency also increased in these rats and the antinociceptive effects were antagonized in a dose-dependent manner by the selective alpha 2 adrenoceptor antagonist idazoxan (dose range 6.7-540 nmol). Intrathecal idazoxan also suppressed the increase in tail flick latency caused by the mu opioid agonist fentanyl (0.74 nmol) given intrathecally. This effect was also dose-dependent. The idazoxan dose-response curve for this suppression of fentanyl antinociception assessed with tail flick latency was the same as that for suppression of xylazine. In contrast, the antinociceptive effects of intrathecal xylazine were not affected by concurrent administration of opioid or GABAA antagonists. We conclude that intrathecal xylazine produced spinally mediated antinociceptive effects by combination with spinal cord alpha 2 adrenoceptors and that neither opioid nor GABA-containing propriospinal neurones were involved in the mediation of this effect. However, alpha 2 adrenoceptors in the spinal cord appear to be involved with antinociception produced by intrathecal fentanyl.

Adrenergic alpha-Agonists↗
PubMed1996

A prospective study to evaluate oophorectomy at the time of vaginal hysterectomy.

OBJECTIVE: To assess the feasibility and safety of vaginal removal of ovaries at the time of vaginal hysterectomy. DESIGN: Prospective study. SETTING: London teaching hospital. POPULATION: Between March 1993 and March 1995, 40 women were admitted under the care of one consultant for vaginal hysterectomy and bilateral oophorectomy. METHODS: The success rate of removing the ovaries vaginally was calculated and the operative time, blood loss, intra- and post-operative complications and patient recovery were analysed and compared with 48 patients who had a vaginal hysterectomy but retained their ovaries during the same time period. RESULTS: Thirty-nine (97.5%) of the 40 women due to undergo removal of the ovaries were managed successfully via the vaginal route; one woman required laparoscopic removal of one of her ovaries containing an ovarian cyst which was not diagnosed pre-operatively. A variety of techniques were used for vaginal oophorectomy which included salpingo-oophorectomy, oophorectomy without salpingectomy, and transvaginal endoscopic oophorectomy utilising endoloop sutures or bipolar electrosurgery. Oophorectomy added a mean of 23.4 min (88.3 vs 64.9 min, 95% CI 10.2-36.7, P < 0.001) to the total operating time compared with vaginal hysterectomy alone. No laparotomies were required, and both the complication rate and post-operative inpatient stay were similar for the two groups. CONCLUSIONS: The need to perform oophorectomy should not be considered a contraindication to vaginal hysterectomy.

Adult↗
PubMed1996

Mild impairment of neuro-otological function in early treated congenital hypothyroidism.

Pure tone audiometry, tympanometry, acoustic stapedial reflex thresholds (ASRTs), and auditory evoked brain stem responses (AEBRs) were carried out in 38 children with early treated congenital hypothyroidism aged 10-12 years, together with tests of vestibular function (electronystagraphy, rotational, and caloric tests). Sensorineural hearing loss with thresholds of greater than 15 dB was detected in 18 children (10 at 8 kHz only); only two children had more than 40 dB hearing loss, each in one ear. Raised ASRTs were found in eight children and two children had abnormal AEBRs. Of the 29 children tested, 12 had an abnormality of vestibular function. Although not significant at the 5% level, there was a tendency for the abnormalities to be more prevalent and severe in the children with more severe hypothyroidism, as judged by pretreatment plasma thyroxine. It is concluded that (i) mild abnormality of hearing is still common in children with congenital hypothyroidism despite early treatment but this is much less severe than that found before neonatal screening and (ii) mild abnormalities of vestibular function may be common in early treated congenital hypothyroidism.

Acoustic Impedance Tests↗
PubMed1996

Locating the stranger rapist.

As part of a larger project evaluating aspects of offender profiling, an initial study was undertaken of the geographic aspects of approximately 300 sexual offences carried out by 79 stranger rapists. The objective was to focus further research on the topic into potentially useful channels, but information thought to be of immediate use to investigating officers was also produced. It was ascertained that at least one-fifth of the sample of stranger rapists were itinerant to a greater or lesser extent. Analysis of the cases where both the offender's address and the location where he approached the victim were known, indicated that the majority of attacks (75 per cent) were initiated within five miles of the offenders' homes. The apparent reasons for victims being approached unusually far away included targeting of locations where numbers of suitable victims were available; raping during relatively sophisticated property offences; 'prowling' or 'hunting' over large areas by subjects who spent considerable amounts of time so doing; access to transport; and familiarity with widely dispersed neighbourhoods, often due to the offender having lived in two or more locations. As a result of this work, future research on the geography of rape will be directed towards those aspects of the offences which have been identified as relevant to the distance between an offender's base and the site where he approached his victim.

Adult↗
PubMed1996

Adaptation of pulmonary receptors in the spontaneously breathing anaesthetized rat.

It has been suggested that species with high breathing frequencies have pulmonary stretch receptors which adapt more rapidly than species with low breathing frequencies. This has proved not to be so. Our hypothesis is that this theory is in fact correct if modified so that overall rate of adaptation of afferent vagal activity, i.e. the sum of stretch and rapidly adapting receptors, is considered. A rapidly breathing species, such as the rat, would thus have a greater proportion of rapidly adapting receptors, than a more slowly breathing species. To test this hypothesis, we measured the proportion of rapidly adapting pulmonary mechanoreceptors in spontaneously breathing rats for comparison with existing results from more slowly breathing species. We found there to be one rapidly adapting receptor for every three slowly adapting receptors present. This measurement has not previously been made in spontaneously breathing rats. The ratio of rapidly to slowly adapting pulmonary receptors in the species sequence cat-rabbit-rat is the same as the ratio of their breathing frequencies (3:4:10). We propose that the difference in proportion of slowly to rapidly adapting pulmonary receptors in different species may be related to their eupnoeic breathing frequency.

Anesthesia↗
PubMed1996

Oral endotracheal intubation of rabbits (Oryctolagus cuniiculus).

Endotracheal intubation of rabbits is reported, both personally and in the literature, to be so difficult that special equipment has been constructed by other workers to facilitate the procedure. We report that the positioning of the operator, behind the animal, viewing from the dorsal surface of the head, facilitates this procedure enormously.

Animals↗
PubMed1996

Technetium-99m-HMPAO labelled leucocytes in the detection and monitoring of inflammatory bowel disease in children.

This study was a retrospective evaluation of the use of technetium-99m hexamethylpropyleneamineoxime (HMPAO) labelled leucocytes in the investigation of suspected inflammatory bowel disease in children. The images were analysed in 35 children and the findings were compared with the results of endoscopy/biopsy, barium studies and antinuclear cytoplasm antibody (ANCA) serology. The sensitivity of the white cell scan was 83% and the specificity 81%. This compares well with other studies in adults and is superior to barium investigations. The technique is recommended as a first line investigation to detect inflammatory bowel disease with a resultant reduction in the use of endoscopy and barium imaging.

Adolescent↗